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authorJunio C Hamano <gitster@pobox.com>2021-07-29 22:29:50 (GMT)
committerJunio C Hamano <gitster@pobox.com>2021-07-29 22:29:50 (GMT)
commitfad749e38c7e8e5f28c08eac4a0a3cca09b1e835 (patch)
treee85e7c3b2f8cb5034cdfd21eb2b1aa65a15ad12c
parentf3dd382cc3409dc609737b523c7c5e30d19ab530 (diff)
parent96b4de5e2772c74c388cae2401ea1ae16091609c (diff)
downloadgit-seen.zip
git-seen.tar.gz
git-seen.tar.bz2
Merge branch 'hn/reftable' into seenseen
The "reftable" backend for the refs API. Seems to break CI jobs in 'seen'. * hn/reftable: (26 commits) t7004: avoid direct filesystem access t1404: annotate test cases with REFFILES t1401,t2011: parameterize HEAD.lock for REFFILES t1301: document what needs to be done for reftable Add "test-tool dump-reftable" command. git-prompt: prepare for reftable refs backend refs: RFC: Reftable support for git-core reftable: add dump utility reftable: implement stack, a mutable database of reftable files. reftable: implement refname validation reftable: add merged table view reftable: add a heap-based priority queue for reftable records reftable: reftable file level tests reftable: read reftable files reftable: generic interface to tables reftable: write reftable files reftable: a generic binary tree implementation reftable: reading/writing blocks Provide zlib's uncompress2 from compat/zlib-compat.c reftable: (de)serialization for the polymorphic record type. ...
-rw-r--r--Documentation/config/extensions.txt9
-rw-r--r--Documentation/technical/repository-version.txt7
-rw-r--r--Makefile54
-rw-r--r--builtin/clone.c5
-rw-r--r--builtin/init-db.c60
-rw-r--r--builtin/stash.c8
-rw-r--r--builtin/worktree.c27
-rw-r--r--cache.h8
-rwxr-xr-xci/lib.sh1
-rw-r--r--compat/.gitattributes1
-rw-r--r--compat/zlib-uncompress2.c92
-rw-r--r--config.mak.uname2
-rw-r--r--configure.ac13
-rw-r--r--contrib/buildsystems/CMakeLists.txt14
-rw-r--r--contrib/buildsystems/Generators/Vcxproj.pm11
-rw-r--r--contrib/completion/git-prompt.sh7
-rw-r--r--hash.h6
-rw-r--r--object-file.c7
-rw-r--r--refs.c26
-rw-r--r--refs.h3
-rw-r--r--refs/refs-internal.h1
-rw-r--r--refs/reftable-backend.c1662
-rw-r--r--reftable/LICENSE31
-rw-r--r--reftable/basics.c128
-rw-r--r--reftable/basics.h60
-rw-r--r--reftable/basics_test.c98
-rw-r--r--reftable/block.c446
-rw-r--r--reftable/block.h127
-rw-r--r--reftable/block_test.c121
-rw-r--r--reftable/blocksource.c148
-rw-r--r--reftable/blocksource.h22
-rw-r--r--reftable/constants.h21
-rw-r--r--reftable/dump.c105
-rw-r--r--reftable/error.c41
-rw-r--r--reftable/generic.c169
-rw-r--r--reftable/generic.h32
-rw-r--r--reftable/iter.c194
-rw-r--r--reftable/iter.h69
-rw-r--r--reftable/merged.c362
-rw-r--r--reftable/merged.h35
-rw-r--r--reftable/merged_test.c292
-rw-r--r--reftable/pq.c115
-rw-r--r--reftable/pq.h32
-rw-r--r--reftable/pq_test.c72
-rw-r--r--reftable/publicbasics.c58
-rw-r--r--reftable/reader.c801
-rw-r--r--reftable/reader.h66
-rw-r--r--reftable/readwrite_test.c650
-rw-r--r--reftable/record.c1200
-rw-r--r--reftable/record.h139
-rw-r--r--reftable/record_test.c407
-rw-r--r--reftable/refname.c209
-rw-r--r--reftable/refname.h29
-rw-r--r--reftable/refname_test.c102
-rw-r--r--reftable/reftable-blocksource.h49
-rw-r--r--reftable/reftable-error.h62
-rw-r--r--reftable/reftable-generic.h47
-rw-r--r--reftable/reftable-iterator.h39
-rw-r--r--reftable/reftable-malloc.h18
-rw-r--r--reftable/reftable-merged.h72
-rw-r--r--reftable/reftable-reader.h101
-rw-r--r--reftable/reftable-record.h114
-rw-r--r--reftable/reftable-stack.h128
-rw-r--r--reftable/reftable-tests.h23
-rw-r--r--reftable/reftable-writer.h148
-rw-r--r--reftable/reftable.c115
-rw-r--r--reftable/stack.c1396
-rw-r--r--reftable/stack.h41
-rw-r--r--reftable/stack_test.c947
-rw-r--r--reftable/system.h24
-rw-r--r--reftable/test_framework.c23
-rw-r--r--reftable/test_framework.h53
-rw-r--r--reftable/tree.c63
-rw-r--r--reftable/tree.h34
-rw-r--r--reftable/tree_test.c61
-rw-r--r--reftable/writer.c690
-rw-r--r--reftable/writer.h50
-rw-r--r--repository.c2
-rw-r--r--repository.h3
-rw-r--r--setup.c6
-rw-r--r--t/helper/test-reftable.c21
-rw-r--r--t/helper/test-tool.c4
-rw-r--r--t/helper/test-tool.h2
-rwxr-xr-xt/t0031-reftable.sh297
-rwxr-xr-xt/t0032-reftable-unittest.sh15
-rwxr-xr-xt/t1301-shared-repo.sh8
-rwxr-xr-xt/t1401-symbolic-ref.sh11
-rwxr-xr-xt/t1404-update-ref-errors.sh56
-rwxr-xr-xt/t1409-avoid-packing-refs.sh6
-rwxr-xr-xt/t1450-fsck.sh6
-rwxr-xr-xt/t2011-checkout-invalid-head.sh11
-rwxr-xr-xt/t3210-pack-refs.sh6
-rwxr-xr-xt/t7004-tag.sh7
-rw-r--r--t/test-lib.sh7
94 files changed, 13108 insertions, 63 deletions
diff --git a/Documentation/config/extensions.txt b/Documentation/config/extensions.txt
index 4e23d73..82c5940 100644
--- a/Documentation/config/extensions.txt
+++ b/Documentation/config/extensions.txt
@@ -6,3 +6,12 @@ extensions.objectFormat::
Note that this setting should only be set by linkgit:git-init[1] or
linkgit:git-clone[1]. Trying to change it after initialization will not
work and will produce hard-to-diagnose issues.
++
+extensions.refStorage::
+ Specify the ref storage mechanism to use. The acceptable values are `files` and
+ `reftable`. If not specified, `files` is assumed. It is an error to specify
+ this key unless `core.repositoryFormatVersion` is 1.
++
+Note that this setting should only be set by linkgit:git-init[1] or
+linkgit:git-clone[1]. Trying to change it after initialization will not
+work and will produce hard-to-diagnose issues.
diff --git a/Documentation/technical/repository-version.txt b/Documentation/technical/repository-version.txt
index 7844ef3..7257623 100644
--- a/Documentation/technical/repository-version.txt
+++ b/Documentation/technical/repository-version.txt
@@ -100,3 +100,10 @@ If set, by default "git config" reads from both "config" and
multiple working directory mode, "config" file is shared while
"config.worktree" is per-working directory (i.e., it's in
GIT_COMMON_DIR/worktrees/<id>/config.worktree)
+
+==== `refStorage`
+
+Specifies the file format for the ref database. Values are `files`
+(for the traditional packed + loose ref format) and `reftable` for the
+binary reftable format. See https://github.com/google/reftable for
+more information.
diff --git a/Makefile b/Makefile
index 98531dd..1d54b35 100644
--- a/Makefile
+++ b/Makefile
@@ -256,6 +256,8 @@ all::
#
# Define NO_DEFLATE_BOUND if your zlib does not have deflateBound.
#
+# Define NO_UNCOMPRESS2 if your zlib does not have uncompress2.
+#
# Define NO_NORETURN if using buggy versions of gcc 4.6+ and profile feedback,
# as the compiler can crash (http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49299)
#
@@ -750,6 +752,7 @@ TEST_BUILTINS_OBJS += test-read-cache.o
TEST_BUILTINS_OBJS += test-read-graph.o
TEST_BUILTINS_OBJS += test-read-midx.o
TEST_BUILTINS_OBJS += test-ref-store.o
+TEST_BUILTINS_OBJS += test-reftable.o
TEST_BUILTINS_OBJS += test-regex.o
TEST_BUILTINS_OBJS += test-repository.o
TEST_BUILTINS_OBJS += test-revision-walking.o
@@ -829,6 +832,8 @@ TEST_SHELL_PATH = $(SHELL_PATH)
LIB_FILE = libgit.a
XDIFF_LIB = xdiff/lib.a
+REFTABLE_LIB = reftable/libreftable.a
+REFTABLE_TEST_LIB = reftable/libreftable_test.a
GENERATED_H += command-list.h
GENERATED_H += config-list.h
@@ -999,6 +1004,7 @@ LIB_OBJS += reflog-walk.o
LIB_OBJS += refs.o
LIB_OBJS += refs/debug.o
LIB_OBJS += refs/files-backend.o
+LIB_OBJS += refs/reftable-backend.o
LIB_OBJS += refs/iterator.o
LIB_OBJS += refs/packed-backend.o
LIB_OBJS += refs/ref-cache.o
@@ -1211,7 +1217,7 @@ THIRD_PARTY_SOURCES += compat/regex/%
THIRD_PARTY_SOURCES += sha1collisiondetection/%
THIRD_PARTY_SOURCES += sha1dc/%
-GITLIBS = common-main.o $(LIB_FILE) $(XDIFF_LIB)
+GITLIBS = common-main.o $(LIB_FILE) $(XDIFF_LIB) $(REFTABLE_LIB)
EXTLIBS =
GIT_USER_AGENT = git/$(GIT_VERSION)
@@ -1751,6 +1757,11 @@ ifdef NO_DEFLATE_BOUND
BASIC_CFLAGS += -DNO_DEFLATE_BOUND
endif
+ifdef NO_UNCOMPRESS2
+ BASIC_CFLAGS += -DNO_UNCOMPRESS2
+ LIB_OBJS += compat/zlib-uncompress2.o
+endif
+
ifdef NO_POSIX_GOODIES
BASIC_CFLAGS += -DNO_POSIX_GOODIES
endif
@@ -2473,7 +2484,36 @@ XDIFF_OBJS += xdiff/xutils.o
.PHONY: xdiff-objs
xdiff-objs: $(XDIFF_OBJS)
+REFTABLE_OBJS += reftable/basics.o
+REFTABLE_OBJS += reftable/error.o
+REFTABLE_OBJS += reftable/block.o
+REFTABLE_OBJS += reftable/blocksource.o
+REFTABLE_OBJS += reftable/iter.o
+REFTABLE_OBJS += reftable/publicbasics.o
+REFTABLE_OBJS += reftable/merged.o
+REFTABLE_OBJS += reftable/pq.o
+REFTABLE_OBJS += reftable/reader.o
+REFTABLE_OBJS += reftable/record.o
+REFTABLE_OBJS += reftable/refname.o
+REFTABLE_OBJS += reftable/generic.o
+REFTABLE_OBJS += reftable/stack.o
+REFTABLE_OBJS += reftable/tree.o
+REFTABLE_OBJS += reftable/writer.o
+
+REFTABLE_TEST_OBJS += reftable/basics_test.o
+REFTABLE_TEST_OBJS += reftable/block_test.o
+REFTABLE_TEST_OBJS += reftable/dump.o
+REFTABLE_TEST_OBJS += reftable/merged_test.o
+REFTABLE_TEST_OBJS += reftable/pq_test.o
+REFTABLE_TEST_OBJS += reftable/record_test.o
+REFTABLE_TEST_OBJS += reftable/readwrite_test.o
+REFTABLE_TEST_OBJS += reftable/refname_test.o
+REFTABLE_TEST_OBJS += reftable/stack_test.o
+REFTABLE_TEST_OBJS += reftable/test_framework.o
+REFTABLE_TEST_OBJS += reftable/tree_test.o
+
TEST_OBJS := $(patsubst %$X,%.o,$(TEST_PROGRAMS)) $(patsubst %,t/helper/%,$(TEST_BUILTINS_OBJS))
+
.PHONY: test-objs
test-objs: $(TEST_OBJS)
@@ -2489,6 +2529,8 @@ OBJECTS += $(PROGRAM_OBJS)
OBJECTS += $(TEST_OBJS)
OBJECTS += $(XDIFF_OBJS)
OBJECTS += $(FUZZ_OBJS)
+OBJECTS += $(REFTABLE_OBJS) $(REFTABLE_TEST_OBJS)
+
ifndef NO_CURL
OBJECTS += http.o http-walker.o remote-curl.o
endif
@@ -2632,6 +2674,12 @@ $(LIB_FILE): $(LIB_OBJS)
$(XDIFF_LIB): $(XDIFF_OBJS)
$(QUIET_AR)$(AR) $(ARFLAGS) $@ $^
+$(REFTABLE_LIB): $(REFTABLE_OBJS)
+ $(QUIET_AR)$(RM) $@ && $(AR) $(ARFLAGS) $@ $^
+
+$(REFTABLE_TEST_LIB): $(REFTABLE_TEST_OBJS)
+ $(QUIET_AR)$(RM) $@ && $(AR) $(ARFLAGS) $@ $^
+
export DEFAULT_EDITOR DEFAULT_PAGER
Documentation/GIT-EXCLUDED-PROGRAMS: FORCE
@@ -2933,7 +2981,7 @@ perf: all
t/helper/test-tool$X: $(patsubst %,t/helper/%,$(TEST_BUILTINS_OBJS))
-t/helper/test-%$X: t/helper/test-%.o GIT-LDFLAGS $(GITLIBS)
+t/helper/test-%$X: t/helper/test-%.o GIT-LDFLAGS $(GITLIBS) $(REFTABLE_TEST_LIB)
$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(filter %.a,$^) $(LIBS)
check-sha1:: t/helper/test-tool$X
@@ -3264,7 +3312,7 @@ cocciclean:
clean: profile-clean coverage-clean cocciclean
$(RM) *.res
$(RM) $(OBJECTS)
- $(RM) $(LIB_FILE) $(XDIFF_LIB)
+ $(RM) $(LIB_FILE) $(XDIFF_LIB) $(REFTABLE_LIB) $(REFTABLE_TEST_LIB)
$(RM) $(ALL_PROGRAMS) $(SCRIPT_LIB) $(BUILT_INS) git$X
$(RM) $(TEST_PROGRAMS)
$(RM) $(FUZZ_PROGRAMS)
diff --git a/builtin/clone.c b/builtin/clone.c
index 87cfbf6..c7a2e72 100644
--- a/builtin/clone.c
+++ b/builtin/clone.c
@@ -1152,7 +1152,7 @@ int cmd_clone(int argc, const char **argv, const char *prefix)
}
init_db(git_dir, real_git_dir, option_template, GIT_HASH_UNKNOWN, NULL,
- INIT_DB_QUIET);
+ default_ref_storage(), INIT_DB_QUIET);
if (real_git_dir)
git_dir = real_git_dir;
@@ -1303,7 +1303,8 @@ int cmd_clone(int argc, const char **argv, const char *prefix)
* Now that we know what algorithm the remote side is using,
* let's set ours to the same thing.
*/
- initialize_repository_version(hash_algo, 1);
+ initialize_repository_version(hash_algo, 1,
+ default_ref_storage());
repo_set_hash_algo(the_repository, hash_algo);
mapped_refs = wanted_peer_refs(refs, &remote->fetch);
diff --git a/builtin/init-db.c b/builtin/init-db.c
index 2167796..22b07d2 100644
--- a/builtin/init-db.c
+++ b/builtin/init-db.c
@@ -167,12 +167,14 @@ static int needs_work_tree_config(const char *git_dir, const char *work_tree)
return 1;
}
-void initialize_repository_version(int hash_algo, int reinit)
+void initialize_repository_version(int hash_algo, int reinit,
+ const char *ref_storage_format)
{
char repo_version_string[10];
int repo_version = GIT_REPO_VERSION;
- if (hash_algo != GIT_HASH_SHA1)
+ if (hash_algo != GIT_HASH_SHA1 ||
+ !strcmp(ref_storage_format, "reftable"))
repo_version = GIT_REPO_VERSION_READ;
/* This forces creation of new config file */
@@ -226,6 +228,7 @@ static int create_default_files(const char *template_path,
is_bare_repository_cfg = init_is_bare_repository || !work_tree;
if (init_shared_repository != -1)
set_shared_repository(init_shared_repository);
+ the_repository->ref_storage_format = xstrdup(fmt->ref_storage);
/*
* We would have created the above under user's umask -- under
@@ -236,6 +239,24 @@ static int create_default_files(const char *template_path,
}
/*
+ * Check to see if .git/HEAD exists; this must happen before
+ * initializing the ref db, because we want to see if there is an
+ * existing HEAD.
+ */
+ path = git_path_buf(&buf, "HEAD");
+ reinit = (!access(path, R_OK) ||
+ readlink(path, junk, sizeof(junk) - 1) != -1);
+
+ /*
+ * refs/heads is a file when using reftable. We can't reinitialize with
+ * a reftable because it will overwrite HEAD
+ */
+ if (reinit && (!strcmp(fmt->ref_storage, "reftable")) ==
+ is_directory(git_path_buf(&buf, "refs/heads"))) {
+ die("cannot switch ref storage format.");
+ }
+
+ /*
* We need to create a "refs" dir in any case so that older
* versions of git can tell that this is a repository.
*/
@@ -249,9 +270,6 @@ static int create_default_files(const char *template_path,
* Point the HEAD symref to the initial branch with if HEAD does
* not yet exist.
*/
- path = git_path_buf(&buf, "HEAD");
- reinit = (!access(path, R_OK)
- || readlink(path, junk, sizeof(junk)-1) != -1);
if (!reinit) {
char *ref;
@@ -268,7 +286,7 @@ static int create_default_files(const char *template_path,
free(ref);
}
- initialize_repository_version(fmt->hash_algo, 0);
+ initialize_repository_version(fmt->hash_algo, 0, fmt->ref_storage);
/* Check filemode trustability */
path = git_path_buf(&buf, "config");
@@ -383,7 +401,7 @@ static void validate_hash_algorithm(struct repository_format *repo_fmt, int hash
int init_db(const char *git_dir, const char *real_git_dir,
const char *template_dir, int hash, const char *initial_branch,
- unsigned int flags)
+ const char *ref_storage_format, unsigned int flags)
{
int reinit;
int exist_ok = flags & INIT_DB_EXIST_OK;
@@ -422,9 +440,31 @@ int init_db(const char *git_dir, const char *real_git_dir,
* is an attempt to reinitialize new repository with an old tool.
*/
check_repository_format(&repo_fmt);
+ repo_fmt.ref_storage = xstrdup(ref_storage_format);
validate_hash_algorithm(&repo_fmt, hash);
+ /*
+ * At this point, the_repository we have in-core does not look
+ * anything like one that we would see initialized in an already
+ * working repository after calling setup_git_directory().
+ *
+ * Calling repository.c::initialize_the_repository() may have
+ * prepared the .index .objects and .parsed_objects members, but
+ * other members like .gitdir, .commondir, etc. have not been
+ * initialized.
+ *
+ * Many API functions assume they are working with the_repository
+ * that has sensibly been initialized, but because we haven't
+ * really read from an existing repository, we need to hand-craft
+ * the necessary members of the structure to get out of this
+ * chicken-and-egg situation.
+ *
+ * For now, we update the hash algorithm member to what the
+ * validate_hash_algorithm() call decided for us.
+ */
+ repo_set_hash_algo(the_repository, repo_fmt.hash_algo);
+
reinit = create_default_files(template_dir, original_git_dir,
initial_branch, &repo_fmt,
flags & INIT_DB_QUIET);
@@ -455,6 +495,9 @@ int init_db(const char *git_dir, const char *real_git_dir,
git_config_set("receive.denyNonFastforwards", "true");
}
+ if (!strcmp(ref_storage_format, "reftable"))
+ git_config_set("extensions.refStorage", ref_storage_format);
+
if (!(flags & INIT_DB_QUIET)) {
int len = strlen(git_dir);
@@ -528,6 +571,7 @@ static const char *const init_db_usage[] = {
int cmd_init_db(int argc, const char **argv, const char *prefix)
{
const char *git_dir;
+ const char *ref_storage_format = default_ref_storage();
const char *real_git_dir = NULL;
const char *work_tree;
const char *template_dir = NULL;
@@ -692,5 +736,5 @@ int cmd_init_db(int argc, const char **argv, const char *prefix)
flags |= INIT_DB_EXIST_OK;
return init_db(git_dir, real_git_dir, template_dir, hash_algo,
- initial_branch, flags);
+ initial_branch, ref_storage_format, flags);
}
diff --git a/builtin/stash.c b/builtin/stash.c
index 8f42360..d43d689 100644
--- a/builtin/stash.c
+++ b/builtin/stash.c
@@ -207,10 +207,16 @@ static int get_stash_info(struct stash_info *info, int argc, const char **argv)
static int do_clear_stash(void)
{
struct object_id obj;
+ int result;
if (get_oid(ref_stash, &obj))
return 0;
- return delete_ref(NULL, ref_stash, &obj, 0);
+ result = delete_ref(NULL, ref_stash, &obj, 0);
+
+ /* Ignore error; this is necessary for reftable, which keeps reflogs
+ * even when refs are deleted. */
+ delete_reflog(ref_stash);
+ return result;
}
static int clear_stash(int argc, const char **argv, const char *prefix)
diff --git a/builtin/worktree.c b/builtin/worktree.c
index 9cb30fc..633c42c 100644
--- a/builtin/worktree.c
+++ b/builtin/worktree.c
@@ -14,6 +14,7 @@
#include "utf8.h"
#include "worktree.h"
#include "quote.h"
+#include "../refs/refs-internal.h"
static const char * const worktree_usage[] = {
N_("git worktree add [<options>] <path> [<commit-ish>]"),
@@ -329,9 +330,29 @@ static int add_worktree(const char *path, const char *refname,
* worktree.
*/
strbuf_reset(&sb);
- strbuf_addf(&sb, "%s/HEAD", sb_repo.buf);
- write_file(sb.buf, "%s", oid_to_hex(null_oid()));
- strbuf_reset(&sb);
+ if (get_main_ref_store(the_repository)->be == &refs_be_reftable) {
+ /* XXX this is cut & paste from reftable_init_db. */
+ strbuf_addf(&sb, "%s/HEAD", sb_repo.buf);
+ write_file(sb.buf, "%s", "ref: refs/heads/.invalid\n");
+ strbuf_reset(&sb);
+
+ strbuf_addf(&sb, "%s/refs", sb_repo.buf);
+ safe_create_dir(sb.buf, 1);
+ strbuf_reset(&sb);
+
+ strbuf_addf(&sb, "%s/refs/heads", sb_repo.buf);
+ write_file(sb.buf, "this repository uses the reftable format");
+ strbuf_reset(&sb);
+
+ strbuf_addf(&sb, "%s/reftable", sb_repo.buf);
+ safe_create_dir(sb.buf, 1);
+ strbuf_reset(&sb);
+ } else {
+ strbuf_addf(&sb, "%s/HEAD", sb_repo.buf);
+ write_file(sb.buf, "%s", oid_to_hex(null_oid()));
+ strbuf_reset(&sb);
+ }
+
strbuf_addf(&sb, "%s/commondir", sb_repo.buf);
write_file(sb.buf, "../..");
diff --git a/cache.h b/cache.h
index 06d8503..670b714 100644
--- a/cache.h
+++ b/cache.h
@@ -656,9 +656,10 @@ int path_inside_repo(const char *prefix, const char *path);
#define INIT_DB_EXIST_OK 0x0002
int init_db(const char *git_dir, const char *real_git_dir,
- const char *template_dir, int hash_algo,
- const char *initial_branch, unsigned int flags);
-void initialize_repository_version(int hash_algo, int reinit);
+ const char *template_dir, int hash_algo, const char *initial_branch,
+ const char *ref_storage_format, unsigned int flags);
+void initialize_repository_version(int hash_algo, int reinit,
+ const char *ref_storage_format);
void sanitize_stdfds(void);
int daemonize(void);
@@ -1075,6 +1076,7 @@ struct repository_format {
int hash_algo;
int sparse_index;
char *work_tree;
+ char *ref_storage;
struct string_list unknown_extensions;
struct string_list v1_only_extensions;
};
diff --git a/ci/lib.sh b/ci/lib.sh
index 476c3f3..5711c63 100755
--- a/ci/lib.sh
+++ b/ci/lib.sh
@@ -224,6 +224,7 @@ linux-gcc-default)
;;
Linux32)
CC=gcc
+ MAKEFLAGS="$MAKEFLAGS NO_UNCOMPRESS2=1"
;;
linux-musl)
CC=gcc
diff --git a/compat/.gitattributes b/compat/.gitattributes
new file mode 100644
index 0000000..40dbfb1
--- /dev/null
+++ b/compat/.gitattributes
@@ -0,0 +1 @@
+/zlib-uncompress2.c whitespace=-indent-with-non-tab,-trailing-space
diff --git a/compat/zlib-uncompress2.c b/compat/zlib-uncompress2.c
new file mode 100644
index 0000000..23b72b4
--- /dev/null
+++ b/compat/zlib-uncompress2.c
@@ -0,0 +1,92 @@
+/* taken from zlib's uncompr.c
+
+ commit cacf7f1d4e3d44d871b605da3b647f07d718623f
+ Author: Mark Adler <madler@alumni.caltech.edu>
+ Date: Sun Jan 15 09:18:46 2017 -0800
+
+ zlib 1.2.11
+
+*/
+
+/*
+ * Copyright (C) 1995-2003, 2010, 2014, 2016 Jean-loup Gailly, Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+#include <zlib.h>
+
+/* clang-format off */
+
+/* ===========================================================================
+ Decompresses the source buffer into the destination buffer. *sourceLen is
+ the byte length of the source buffer. Upon entry, *destLen is the total size
+ of the destination buffer, which must be large enough to hold the entire
+ uncompressed data. (The size of the uncompressed data must have been saved
+ previously by the compressor and transmitted to the decompressor by some
+ mechanism outside the scope of this compression library.) Upon exit,
+ *destLen is the size of the decompressed data and *sourceLen is the number
+ of source bytes consumed. Upon return, source + *sourceLen points to the
+ first unused input byte.
+
+ uncompress returns Z_OK if success, Z_MEM_ERROR if there was not enough
+ memory, Z_BUF_ERROR if there was not enough room in the output buffer, or
+ Z_DATA_ERROR if the input data was corrupted, including if the input data is
+ an incomplete zlib stream.
+*/
+int ZEXPORT uncompress2 (
+ Bytef *dest,
+ uLongf *destLen,
+ const Bytef *source,
+ uLong *sourceLen) {
+ z_stream stream;
+ int err;
+ const uInt max = (uInt)-1;
+ uLong len, left;
+ Byte buf[1]; /* for detection of incomplete stream when *destLen == 0 */
+
+ len = *sourceLen;
+ if (*destLen) {
+ left = *destLen;
+ *destLen = 0;
+ }
+ else {
+ left = 1;
+ dest = buf;
+ }
+
+ stream.next_in = (z_const Bytef *)source;
+ stream.avail_in = 0;
+ stream.zalloc = (alloc_func)0;
+ stream.zfree = (free_func)0;
+ stream.opaque = (voidpf)0;
+
+ err = inflateInit(&stream);
+ if (err != Z_OK) return err;
+
+ stream.next_out = dest;
+ stream.avail_out = 0;
+
+ do {
+ if (stream.avail_out == 0) {
+ stream.avail_out = left > (uLong)max ? max : (uInt)left;
+ left -= stream.avail_out;
+ }
+ if (stream.avail_in == 0) {
+ stream.avail_in = len > (uLong)max ? max : (uInt)len;
+ len -= stream.avail_in;
+ }
+ err = inflate(&stream, Z_NO_FLUSH);
+ } while (err == Z_OK);
+
+ *sourceLen -= len + stream.avail_in;
+ if (dest != buf)
+ *destLen = stream.total_out;
+ else if (stream.total_out && err == Z_BUF_ERROR)
+ left = 1;
+
+ inflateEnd(&stream);
+ return err == Z_STREAM_END ? Z_OK :
+ err == Z_NEED_DICT ? Z_DATA_ERROR :
+ err == Z_BUF_ERROR && left + stream.avail_out ? Z_DATA_ERROR :
+ err;
+}
diff --git a/config.mak.uname b/config.mak.uname
index 4be0bc3..59726d6 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -718,7 +718,7 @@ vcxproj:
# Make .vcxproj files and add them
unset QUIET_GEN QUIET_BUILT_IN; \
perl contrib/buildsystems/generate -g Vcxproj
- git add -f git.sln {*,*/lib,t/helper/*}/*.vcxproj
+ git add -f git.sln {*,*/lib,*/libreftable,t/helper/*}/*.vcxproj
# Generate the LinkOrCopyBuiltins.targets and LinkOrCopyRemoteHttp.targets file
(echo '<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">' && \
diff --git a/configure.ac b/configure.ac
index 031e8d3..c3a9131 100644
--- a/configure.ac
+++ b/configure.ac
@@ -672,9 +672,22 @@ AC_LINK_IFELSE([ZLIBTEST_SRC],
NO_DEFLATE_BOUND=yes])
LIBS="$old_LIBS"
+AC_DEFUN([ZLIBTEST_UNCOMPRESS2_SRC], [
+AC_LANG_PROGRAM([#include <zlib.h>],
+ [uncompress2(NULL,NULL,NULL,NULL);])])
+AC_MSG_CHECKING([for uncompress2 in -lz])
+old_LIBS="$LIBS"
+LIBS="$LIBS -lz"
+AC_LINK_IFELSE([ZLIBTEST_UNCOMPRESS2_SRC],
+ [AC_MSG_RESULT([yes])],
+ [AC_MSG_RESULT([no])
+ NO_UNCOMPRESS2=yes])
+LIBS="$old_LIBS"
+
GIT_UNSTASH_FLAGS($ZLIB_PATH)
GIT_CONF_SUBST([NO_DEFLATE_BOUND])
+GIT_CONF_SUBST([NO_UNCOMPRESS2])
#
# Define NEEDS_SOCKET if linking with libc is not enough (SunOS,
diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt
index b0ffe47..eb9fc53 100644
--- a/contrib/buildsystems/CMakeLists.txt
+++ b/contrib/buildsystems/CMakeLists.txt
@@ -655,6 +655,12 @@ parse_makefile_for_sources(libxdiff_SOURCES "XDIFF_OBJS")
list(TRANSFORM libxdiff_SOURCES PREPEND "${CMAKE_SOURCE_DIR}/")
add_library(xdiff STATIC ${libxdiff_SOURCES})
+#reftable
+parse_makefile_for_sources(reftable_SOURCES "REFTABLE_OBJS")
+
+list(TRANSFORM reftable_SOURCES PREPEND "${CMAKE_SOURCE_DIR}/")
+add_library(reftable STATIC ${reftable_SOURCES})
+
if(WIN32)
if(NOT MSVC)#use windres when compiling with gcc and clang
add_custom_command(OUTPUT ${CMAKE_BINARY_DIR}/git.res
@@ -677,7 +683,7 @@ endif()
#link all required libraries to common-main
add_library(common-main OBJECT ${CMAKE_SOURCE_DIR}/common-main.c)
-target_link_libraries(common-main libgit xdiff ${ZLIB_LIBRARIES})
+target_link_libraries(common-main libgit xdiff reftable ${ZLIB_LIBRARIES})
if(Intl_FOUND)
target_link_libraries(common-main ${Intl_LIBRARIES})
endif()
@@ -917,11 +923,15 @@ if(BUILD_TESTING)
add_executable(test-fake-ssh ${CMAKE_SOURCE_DIR}/t/helper/test-fake-ssh.c)
target_link_libraries(test-fake-ssh common-main)
+#reftable-tests
+parse_makefile_for_sources(test-reftable_SOURCES "REFTABLE_TEST_OBJS")
+list(TRANSFORM test-reftable_SOURCES PREPEND "${CMAKE_SOURCE_DIR}/")
+
#test-tool
parse_makefile_for_sources(test-tool_SOURCES "TEST_BUILTINS_OBJS")
list(TRANSFORM test-tool_SOURCES PREPEND "${CMAKE_SOURCE_DIR}/t/helper/")
-add_executable(test-tool ${CMAKE_SOURCE_DIR}/t/helper/test-tool.c ${test-tool_SOURCES})
+add_executable(test-tool ${CMAKE_SOURCE_DIR}/t/helper/test-tool.c ${test-tool_SOURCES} ${test-reftable_SOURCES})
target_link_libraries(test-tool common-main)
set_target_properties(test-fake-ssh test-tool
diff --git a/contrib/buildsystems/Generators/Vcxproj.pm b/contrib/buildsystems/Generators/Vcxproj.pm
index d258445..1a25789 100644
--- a/contrib/buildsystems/Generators/Vcxproj.pm
+++ b/contrib/buildsystems/Generators/Vcxproj.pm
@@ -77,7 +77,7 @@ sub createProject {
my $libs_release = "\n ";
my $libs_debug = "\n ";
if (!$static_library) {
- $libs_release = join(";", sort(grep /^(?!libgit\.lib|xdiff\/lib\.lib|vcs-svn\/lib\.lib)/, @{$$build_structure{"$prefix${name}_LIBS"}}));
+ $libs_release = join(";", sort(grep /^(?!libgit\.lib|xdiff\/lib\.lib|vcs-svn\/lib\.lib|reftable\/libreftable\.lib)/, @{$$build_structure{"$prefix${name}_LIBS"}}));
$libs_debug = $libs_release;
$libs_debug =~ s/zlib\.lib/zlibd\.lib/g;
$libs_debug =~ s/libexpat\.lib/libexpatd\.lib/g;
@@ -232,6 +232,7 @@ EOM
EOM
if (!$static_library || $target =~ 'vcs-svn' || $target =~ 'xdiff') {
my $uuid_libgit = $$build_structure{"LIBS_libgit_GUID"};
+ my $uuid_libreftable = $$build_structure{"LIBS_reftable/libreftable_GUID"};
my $uuid_xdiff_lib = $$build_structure{"LIBS_xdiff/lib_GUID"};
print F << "EOM";
@@ -241,6 +242,14 @@ EOM
<ReferenceOutputAssembly>false</ReferenceOutputAssembly>
</ProjectReference>
EOM
+ if (!($name =~ /xdiff|libreftable/)) {
+ print F << "EOM";
+ <ProjectReference Include="$cdup\\reftable\\libreftable\\libreftable.vcxproj">
+ <Project>$uuid_libreftable</Project>
+ <ReferenceOutputAssembly>false</ReferenceOutputAssembly>
+ </ProjectReference>
+EOM
+ }
if (!($name =~ 'xdiff')) {
print F << "EOM";
<ProjectReference Include="$cdup\\xdiff\\lib\\xdiff_lib.vcxproj">
diff --git a/contrib/completion/git-prompt.sh b/contrib/completion/git-prompt.sh
index db7c006..4177274 100644
--- a/contrib/completion/git-prompt.sh
+++ b/contrib/completion/git-prompt.sh
@@ -478,10 +478,15 @@ __git_ps1 ()
if ! __git_eread "$g/HEAD" head; then
return $exit
fi
- # is it a symbolic ref?
b="${head#ref: }"
if [ "$head" = "$b" ]; then
detached=yes
+ elif [ "$b" = "refs/heads/.invalid" ]; then
+ # Reftable
+ b="$(git symbolic-ref HEAD 2>/dev/null)" ||
+ detached=yes
+ fi
+ if [ "$detached" = yes ]; then
b="$(
case "${GIT_PS1_DESCRIBE_STYLE-}" in
(contains)
diff --git a/hash.h b/hash.h
index 27a1802..f9e8d4b 100644
--- a/hash.h
+++ b/hash.h
@@ -95,12 +95,18 @@ static inline void git_SHA256_Clone(git_SHA256_CTX *dst, const git_SHA256_CTX *s
/* Number of algorithms supported (including unknown). */
#define GIT_HASH_NALGOS (GIT_HASH_SHA256 + 1)
+/* "sha1", big-endian */
+#define GIT_SHA1_FORMAT_ID 0x73686131
+
/* The length in bytes and in hex digits of an object name (SHA-1 value). */
#define GIT_SHA1_RAWSZ 20
#define GIT_SHA1_HEXSZ (2 * GIT_SHA1_RAWSZ)
/* The block size of SHA-1. */
#define GIT_SHA1_BLKSZ 64
+/* "s256", big-endian */
+#define GIT_SHA256_FORMAT_ID 0x73323536
+
/* The length in bytes and in hex digits of an object name (SHA-256 value). */
#define GIT_SHA256_RAWSZ 32
#define GIT_SHA256_HEXSZ (2 * GIT_SHA256_RAWSZ)
diff --git a/object-file.c b/object-file.c
index 027c00e..f388375 100644
--- a/object-file.c
+++ b/object-file.c
@@ -164,7 +164,6 @@ static void git_hash_unknown_final_oid(struct object_id *oid, git_hash_ctx *ctx)
BUG("trying to finalize unknown hash");
}
-
const struct git_hash_algo hash_algos[GIT_HASH_NALGOS] = {
{
NULL,
@@ -183,8 +182,7 @@ const struct git_hash_algo hash_algos[GIT_HASH_NALGOS] = {
},
{
"sha1",
- /* "sha1", big-endian */
- 0x73686131,
+ GIT_SHA1_FORMAT_ID,
GIT_SHA1_RAWSZ,
GIT_SHA1_HEXSZ,
GIT_SHA1_BLKSZ,
@@ -199,8 +197,7 @@ const struct git_hash_algo hash_algos[GIT_HASH_NALGOS] = {
},
{
"sha256",
- /* "s256", big-endian */
- 0x73323536,
+ GIT_SHA256_FORMAT_ID,
GIT_SHA256_RAWSZ,
GIT_SHA256_HEXSZ,
GIT_SHA256_BLKSZ,
diff --git a/refs.c b/refs.c
index 09de09d..232013f 100644
--- a/refs.c
+++ b/refs.c
@@ -20,10 +20,15 @@
#include "repository.h"
#include "sigchain.h"
+const char *default_ref_storage(void)
+{
+ return git_env_bool("GIT_TEST_REFTABLE", 0) ? "reftable" : "files";
+}
+
/*
* List of all available backends
*/
-static struct ref_storage_be *refs_backends = &refs_be_files;
+static struct ref_storage_be *refs_backends = &refs_be_reftable;
static struct ref_storage_be *find_ref_storage_backend(const char *name)
{
@@ -1896,13 +1901,13 @@ static struct ref_store *lookup_ref_store_map(struct hashmap *map,
* Create, record, and return a ref_store instance for the specified
* gitdir.
*/
-static struct ref_store *ref_store_init(const char *gitdir,
+static struct ref_store *ref_store_init(const char *gitdir, const char *be_name,
unsigned int flags)
{
- const char *be_name = "files";
- struct ref_storage_be *be = find_ref_storage_backend(be_name);
+ struct ref_storage_be *be;
struct ref_store *refs;
+ be = find_ref_storage_backend(be_name);
if (!be)
BUG("reference backend %s is unknown", be_name);
@@ -1918,7 +1923,11 @@ struct ref_store *get_main_ref_store(struct repository *r)
if (!r->gitdir)
BUG("attempting to get main_ref_store outside of repository");
- r->refs_private = ref_store_init(r->gitdir, REF_STORE_ALL_CAPS);
+ r->refs_private = ref_store_init(r->gitdir,
+ r->ref_storage_format ?
+ r->ref_storage_format :
+ default_ref_storage(),
+ REF_STORE_ALL_CAPS);
r->refs_private = maybe_debug_wrap_ref_store(r->gitdir, r->refs_private);
return r->refs_private;
}
@@ -1974,7 +1983,7 @@ struct ref_store *get_submodule_ref_store(const char *submodule)
goto done;
/* assume that add_submodule_odb() has been called */
- refs = ref_store_init(submodule_sb.buf,
+ refs = ref_store_init(submodule_sb.buf, default_ref_storage(),
REF_STORE_READ | REF_STORE_ODB);
register_ref_store_map(&submodule_ref_stores, "submodule",
refs, submodule);
@@ -1988,6 +1997,7 @@ done:
struct ref_store *get_worktree_ref_store(const struct worktree *wt)
{
+ const char *format = default_ref_storage();
struct ref_store *refs;
const char *id;
@@ -2001,9 +2011,9 @@ struct ref_store *get_worktree_ref_store(const struct worktree *wt)
if (wt->id)
refs = ref_store_init(git_common_path("worktrees/%s", wt->id),
- REF_STORE_ALL_CAPS);
+ format, REF_STORE_ALL_CAPS);
else
- refs = ref_store_init(get_git_common_dir(),
+ refs = ref_store_init(get_git_common_dir(), format,
REF_STORE_ALL_CAPS);
if (refs)
diff --git a/refs.h b/refs.h
index 9a5b476..3e4ee01 100644
--- a/refs.h
+++ b/refs.h
@@ -11,6 +11,9 @@ struct string_list;
struct string_list_item;
struct worktree;
+/* Returns the ref storage backend to use by default. */
+const char *default_ref_storage(void);
+
/*
* Resolve a reference, recursively following symbolic refererences.
*
diff --git a/refs/refs-internal.h b/refs/refs-internal.h
index 9aa4af8..b8b12dd 100644
--- a/refs/refs-internal.h
+++ b/refs/refs-internal.h
@@ -676,6 +676,7 @@ struct ref_storage_be {
};
extern struct ref_storage_be refs_be_files;
+extern struct ref_storage_be refs_be_reftable;
extern struct ref_storage_be refs_be_packed;
/*
diff --git a/refs/reftable-backend.c b/refs/reftable-backend.c
new file mode 100644
index 0000000..60da0bc
--- /dev/null
+++ b/refs/reftable-backend.c
@@ -0,0 +1,1662 @@
+#include "../cache.h"
+#include "../chdir-notify.h"
+#include "../config.h"
+#include "../iterator.h"
+#include "../lockfile.h"
+#include "../refs.h"
+#include "../reftable/reftable-stack.h"
+#include "../reftable/reftable-record.h"
+#include "../reftable/reftable-error.h"
+#include "../reftable/reftable-blocksource.h"
+#include "../reftable/reftable-reader.h"
+#include "../reftable/reftable-iterator.h"
+#include "../reftable/reftable-merged.h"
+#include "../reftable/reftable-generic.h"
+#include "../worktree.h"
+#include "refs-internal.h"
+
+extern struct ref_storage_be refs_be_reftable;
+
+struct git_reftable_ref_store {
+ struct ref_store base;
+ unsigned int store_flags;
+
+ int err;
+ char *repo_dir;
+
+ char *reftable_dir;
+
+ struct reftable_stack *main_stack;
+ struct reftable_stack *worktree_stack;
+};
+
+/*
+ * Some refs are global to the repository (refs/heads/{*}), while others are
+ * local to the worktree (eg. HEAD, refs/bisect/{*}). We solve this by having
+ * two separate databases (ie. two reftable/ directories), one for the
+ * repository, and one for the worktree. For reading, we merge the view (see
+ * git_reftable_iterator) of both, when necessary.
+ *
+ * Unfortunately, the worktrees can also be selected by specifying a magic
+ * refname (eg. worktree/BLA/refname, even if BLA isn't the current worktree.)
+ */
+static struct reftable_stack *stack_for(struct git_reftable_ref_store *store,
+ const char *refname)
+{
+ const char *wtname = refname;
+ int wtname_len = 0;
+ const char *wtref = refname;
+
+ if (refname == NULL)
+ return store->main_stack;
+
+ if (!parse_worktree_ref(refname, &wtname, &wtname_len, &wtref) &&
+ wtname_len) {
+ /* this makes me cry. Woe you if you try to access
+ * worktree/BLA/REF and the current worktree
+ * from the same process.
+ */
+ struct strbuf wt_dir = STRBUF_INIT;
+ struct reftable_write_options cfg = {
+ .block_size = 4096,
+ .hash_id = the_hash_algo->format_id,
+ };
+
+ strbuf_addstr(&wt_dir, store->base.gitdir);
+ strbuf_addstr(&wt_dir, "/worktrees/");
+ strbuf_add(&wt_dir, wtname, wtname_len);
+ strbuf_addstr(&wt_dir, "/reftable");
+
+ if (store->worktree_stack)
+ reftable_stack_destroy(store->worktree_stack);
+ store->err = reftable_new_stack(&store->worktree_stack,
+ wt_dir.buf, cfg);
+ assert(store->err != REFTABLE_API_ERROR);
+
+ return store->worktree_stack;
+ }
+
+ if (store->worktree_stack == NULL)
+ return store->main_stack;
+
+ switch (ref_type(refname)) {
+ case REF_TYPE_PER_WORKTREE:
+ case REF_TYPE_PSEUDOREF:
+ case REF_TYPE_OTHER_PSEUDOREF:
+ return store->worktree_stack;
+ default:
+ case REF_TYPE_MAIN_PSEUDOREF:
+ case REF_TYPE_NORMAL:
+ return store->main_stack;
+ }
+}
+
+static const char *bare_ref_name(const char *ref)
+{
+ const char *out = ref;
+ int name_len = 0;
+ if (skip_prefix(ref, "main-worktree/", &out))
+ return out;
+
+ if (!parse_worktree_ref(ref, NULL, &name_len, &out) && name_len) {
+ return out;
+ }
+
+ return ref;
+}
+
+static int git_reftable_read_raw_ref(struct ref_store *ref_store,
+ const char *refname, struct object_id *oid,
+ struct strbuf *referent,
+ unsigned int *type, int *failure_errno);
+
+static void clear_reftable_log_record(struct reftable_log_record *log)
+{
+ log->refname = NULL;
+ switch (log->value_type) {
+ case REFTABLE_LOG_UPDATE:
+ log->update.old_hash = NULL;
+ log->update.new_hash = NULL;
+ log->update.message = NULL;
+ break;
+ case REFTABLE_LOG_DELETION:
+ break;
+ }
+ reftable_log_record_release(log);
+}
+
+static void fill_reftable_log_record(struct reftable_log_record *log)
+{
+ const char *info = git_committer_info(0);
+ struct ident_split split = { NULL };
+ int result = split_ident_line(&split, info, strlen(info));
+ int sign = 1;
+ assert(0 == result);
+
+ reftable_log_record_release(log);
+ log->value_type = REFTABLE_LOG_UPDATE;
+ log->update.name =
+ xstrndup(split.name_begin, split.name_end - split.name_begin);
+ log->update.email =
+ xstrndup(split.mail_begin, split.mail_end - split.mail_begin);
+ log->update.time = atol(split.date_begin);
+ if (*split.tz_begin == '-') {
+ sign = -1;
+ split.tz_begin++;
+ }
+ if (*split.tz_begin == '+') {
+ sign = 1;
+ split.tz_begin++;
+ }
+
+ log->update.tz_offset = sign * atoi(split.tz_begin);
+}
+
+static int has_suffix(struct strbuf *b, const char *suffix)
+{
+ size_t len = strlen(suffix);
+
+ if (len > b->len) {
+ return 0;
+ }
+
+ return 0 == strncmp(b->buf + b->len - len, suffix, len);
+}
+
+/* trims the last path component of b. Returns -1 if it is not
+ * present, or 0 on success
+ */
+static int trim_component(struct strbuf *b)
+{
+ char *last;
+ last = strrchr(b->buf, '/');
+ if (!last)
+ return -1;
+ strbuf_setlen(b, last - b->buf);
+ return 0;
+}
+
+/* Returns whether `b` is a worktree path. Mutates its arg, trimming it to the
+ * gitdir
+ */
+static int is_worktree(struct strbuf *b)
+{
+ if (trim_component(b) < 0) {
+ return 0;
+ }
+ if (!has_suffix(b, "/worktrees")) {
+ return 0;
+ }
+ trim_component(b);
+ return 1;
+}
+
+static struct ref_store *git_reftable_ref_store_create(const char *path,
+ unsigned int store_flags)
+{
+ struct git_reftable_ref_store *refs = xcalloc(1, sizeof(*refs));
+ struct ref_store *ref_store = (struct ref_store *)refs;
+ struct reftable_write_options cfg = {
+ .block_size = 4096,
+ .hash_id = the_hash_algo->format_id,
+ };
+ struct strbuf sb = STRBUF_INIT;
+ const char *gitdir = path;
+ struct strbuf wt_buf = STRBUF_INIT;
+ int wt = 0;
+
+ strbuf_realpath(&wt_buf, path, /*die_on_error=*/0);
+
+ /* this is clumsy, but the official worktree functions (eg.
+ * get_worktrees()) function will try to initialize a ref storage
+ * backend, leading to infinite recursion. */
+ wt = is_worktree(&wt_buf);
+ if (wt) {
+ gitdir = wt_buf.buf;
+ }
+
+ base_ref_store_init(ref_store, &refs_be_reftable);
+ ref_store->gitdir = xstrdup(gitdir);
+ refs->store_flags = store_flags;
+ strbuf_addf(&sb, "%s/reftable", gitdir);
+ refs->reftable_dir = xstrdup(sb.buf);
+ strbuf_reset(&sb);
+
+ refs->err =
+ reftable_new_stack(&refs->main_stack, refs->reftable_dir, cfg);
+ assert(refs->err != REFTABLE_API_ERROR);
+
+ if (refs->err == 0 && wt) {
+ strbuf_addf(&sb, "%s/reftable", path);
+
+ refs->err =
+ reftable_new_stack(&refs->worktree_stack, sb.buf, cfg);
+ assert(refs->err != REFTABLE_API_ERROR);
+ }
+
+ strbuf_release(&sb);
+ strbuf_release(&wt_buf);
+ return ref_store;
+}
+
+static int git_reftable_init_db(struct ref_store *ref_store, struct strbuf *err)
+{
+ struct git_reftable_ref_store *refs =
+ (struct git_reftable_ref_store *)ref_store;
+ struct strbuf sb = STRBUF_INIT;
+
+ safe_create_dir(refs->reftable_dir, 1);
+
+ strbuf_addf(&sb, "%s/HEAD", refs->base.gitdir);
+ write_file(sb.buf, "ref: refs/heads/.invalid");
+ strbuf_reset(&sb);
+
+ strbuf_addf(&sb, "%s/refs", refs->base.gitdir);
+ safe_create_dir(sb.buf, 1);
+ strbuf_reset(&sb);
+
+ strbuf_addf(&sb, "%s/refs/heads", refs->base.gitdir);
+ write_file(sb.buf, "this repository uses the reftable format");
+
+ return 0;
+}
+
+struct git_reftable_iterator {
+ struct ref_iterator base;
+ struct reftable_iterator iter;
+ struct reftable_ref_record ref;
+ struct object_id oid;
+ struct ref_store *ref_store;
+
+ /* In case we must iterate over 2 stacks, this is non-null. */
+ struct reftable_merged_table *merged;
+ unsigned int flags;
+ int err;
+ const char *prefix;
+};
+
+static int reftable_ref_iterator_advance(struct ref_iterator *ref_iterator)
+{
+ struct git_reftable_iterator *ri =
+ (struct git_reftable_iterator *)ref_iterator;
+ while (ri->err == 0) {
+ ri->err = reftable_iterator_next_ref(&ri->iter, &ri->ref);
+ if (ri->err) {
+ break;
+ }
+
+ if (ref_type(ri->ref.refname) == REF_TYPE_PSEUDOREF) {
+ /*
+ pseudorefs, eg. HEAD, FETCH_HEAD should not be
+ produced, by default.
+ */
+ continue;
+ }
+ ri->base.refname = ri->ref.refname;
+ if (ri->prefix != NULL &&
+ strncmp(ri->prefix, ri->ref.refname, strlen(ri->prefix))) {
+ ri->err = 1;
+ break;
+ }
+ if (ri->flags & DO_FOR_EACH_PER_WORKTREE_ONLY &&
+ ref_type(ri->base.refname) != REF_TYPE_PER_WORKTREE)
+ continue;
+
+ ri->base.flags = 0;
+ switch (ri->ref.value_type) {
+ case REFTABLE_REF_VAL1:
+ oidread(&ri->oid, ri->ref.value.val1);
+ break;
+ case REFTABLE_REF_VAL2:
+ oidread(&ri->oid, ri->ref.value.val2.value);
+ break;
+ case REFTABLE_REF_SYMREF: {
+ int out_flags = 0;
+ const char *resolved = refs_resolve_ref_unsafe(
+ ri->ref_store, ri->ref.refname,
+ RESOLVE_REF_READING, &ri->oid, &out_flags);
+ ri->base.flags = out_flags;
+ if (resolved == NULL &&
+ !(ri->flags & DO_FOR_EACH_INCLUDE_BROKEN) &&
+ (ri->base.flags & REF_ISBROKEN)) {
+ continue;
+ }
+ break;
+ }
+ default:
+ abort();
+ }
+
+ ri->base.oid = &ri->oid;
+ if (!(ri->flags & DO_FOR_EACH_INCLUDE_BROKEN) &&
+ !ref_resolves_to_object(ri->base.refname, ri->base.oid,
+ ri->base.flags)) {
+ continue;
+ }
+
+ break;
+ }
+
+ if (ri->err > 0) {
+ return ITER_DONE;
+ }
+ if (ri->err < 0) {
+ return ITER_ERROR;
+ }
+
+ return ITER_OK;
+}
+
+static int reftable_ref_iterator_peel(struct ref_iterator *ref_iterator,
+ struct object_id *peeled)
+{
+ struct git_reftable_iterator *ri =
+ (struct git_reftable_iterator *)ref_iterator;
+ if (ri->ref.value_type == REFTABLE_REF_VAL2) {
+ oidread(peeled, ri->ref.value.val2.target_value);
+ return 0;
+ }
+
+ return 1;
+}
+
+static int reftable_ref_iterator_abort(struct ref_iterator *ref_iterator)
+{
+ struct git_reftable_iterator *ri =
+ (struct git_reftable_iterator *)ref_iterator;
+ reftable_ref_record_release(&ri->ref);
+ reftable_iterator_destroy(&ri->iter);
+ if (ri->merged) {
+ reftable_merged_table_free(ri->merged);
+ }
+ return 0;
+}
+
+static struct ref_iterator_vtable reftable_ref_iterator_vtable = {
+ reftable_ref_iterator_advance, reftable_ref_iterator_peel,
+ reftable_ref_iterator_abort
+};
+
+static struct ref_iterator *
+git_reftable_ref_iterator_begin(struct ref_store *ref_store, const char *prefix,
+ unsigned int flags)
+{
+ struct git_reftable_ref_store *refs =
+ (struct git_reftable_ref_store *)ref_store;
+ struct git_reftable_iterator *ri = xcalloc(1, sizeof(*ri));
+
+ if (refs->err < 0) {
+ ri->err = refs->err;
+ } else if (refs->worktree_stack == NULL) {
+ struct reftable_merged_table *mt =
+ reftable_stack_merged_table(refs->main_stack);
+ ri->err = reftable_merged_table_seek_ref(mt, &ri->iter, prefix);
+ } else {
+ struct reftable_merged_table *mt1 =
+ reftable_stack_merged_table(refs->main_stack);
+ struct reftable_merged_table *mt2 =
+ reftable_stack_merged_table(refs->worktree_stack);
+ struct reftable_table *tabs =
+ xcalloc(2, sizeof(struct reftable_table));
+ reftable_table_from_merged_table(&tabs[0], mt1);
+ reftable_table_from_merged_table(&tabs[1], mt2);
+ ri->err = reftable_new_merged_table(&ri->merged, tabs, 2,
+ the_hash_algo->format_id);
+ if (ri->err == 0)
+ ri->err = reftable_merged_table_seek_ref(
+ ri->merged, &ri->iter, prefix);
+ }
+
+ base_ref_iterator_init(&ri->base, &reftable_ref_iterator_vtable, 1);
+ ri->prefix = prefix;
+ ri->base.oid = &ri->oid;
+ ri->flags = flags;
+ ri->ref_store = ref_store;
+ return &ri->base;
+}
+
+static int fixup_symrefs(struct ref_store *ref_store,
+ struct ref_transaction *transaction)
+{
+ struct strbuf referent = STRBUF_INIT;
+ int i = 0;
+ int err = 0;
+
+ for (i = 0; i < transaction->nr; i++) {
+ struct ref_update *update = transaction->updates[i];
+ struct object_id old_oid;
+ int failure_errno;
+
+ err = git_reftable_read_raw_ref(ref_store, update->refname,
+ &old_oid, &referent,
+ /* mutate input, like
+ files-backend.c */
+ &update->type, &failure_errno);
+ if (err < 0 && failure_errno == ENOENT &&
+ is_null_oid(&update->old_oid)) {
+ err = 0;
+ }
+ if (err < 0)
+ goto done;
+
+ if (!(update->type & REF_ISSYMREF))
+ continue;
+
+ if (update->flags & REF_NO_DEREF) {
+ /* what should happen here? See files-backend.c
+ * lock_ref_for_update. */
+ } else {
+ /*
+ If we are updating a symref (eg. HEAD), we should also
+ update the branch that the symref points to.
+
+ This is generic functionality, and would be better
+ done in refs.c, but the current implementation is
+ intertwined with the locking in files-backend.c.
+ */
+ int new_flags = update->flags;
+ struct ref_update *new_update = NULL;
+
+ /* if this is an update for HEAD, should also record a
+ log entry for HEAD? See files-backend.c,
+ split_head_update()
+ */
+ new_update = ref_transaction_add_update(
+ transaction, referent.buf, new_flags,
+ &update->new_oid, &update->old_oid,
+ update->msg);
+ new_update->parent_update = update;
+
+ /* files-backend sets REF_LOG_ONLY here. */
+ update->flags |= REF_NO_DEREF | REF_LOG_ONLY;
+ update->flags &= ~REF_HAVE_OLD;
+ }
+ }
+
+done:
+ assert(err != REFTABLE_API_ERROR);
+ strbuf_release(&referent);
+ return err;
+}
+
+static int git_reftable_transaction_prepare(struct ref_store *ref_store,
+ struct ref_transaction *transaction,
+ struct strbuf *errbuf)
+{
+ struct git_reftable_ref_store *refs =
+ (struct git_reftable_ref_store *)ref_store;
+ struct reftable_addition *add = NULL;
+ struct reftable_stack *stack = stack_for(
+ refs,
+ transaction->nr ? transaction->updates[0]->refname : NULL);
+
+ int err = refs->err;
+ if (err < 0) {
+ goto done;
+ }
+
+ err = reftable_stack_reload(stack);
+ if (err) {
+ goto done;
+ }
+
+ err = reftable_stack_new_addition(&add, stack);
+ if (err) {
+ goto done;
+ }
+
+ err = fixup_symrefs(ref_store, transaction);
+ if (err) {
+ goto done;
+ }
+
+ transaction->backend_data = add;
+ transaction->state = REF_TRANSACTION_PREPARED;
+
+done:
+ assert(err != REFTABLE_API_ERROR);
+ if (err < 0) {
+ transaction->state = REF_TRANSACTION_CLOSED;
+ strbuf_addf(errbuf, "reftable: transaction prepare: %s",
+ reftable_error_str(err));
+ }
+
+ return err;
+}
+
+static int git_reftable_transaction_abort(struct ref_store *ref_store,
+ struct ref_transaction *transaction,
+ struct strbuf *err)
+{
+ struct reftable_addition *add =
+ (struct reftable_addition *)transaction->backend_data;
+ reftable_addition_destroy(add);
+ transaction->backend_data = NULL;
+ return 0;
+}
+
+static int reftable_check_old_oid(struct ref_store *refs, const char *refname,
+ struct object_id *want_oid)
+{
+ struct object_id out_oid;
+ int out_flags = 0;
+ const char *resolved = refs_resolve_ref_unsafe(
+ refs, refname, RESOLVE_REF_READING, &out_oid, &out_flags);
+ if (is_null_oid(want_oid) != (resolved == NULL)) {
+ return REFTABLE_LOCK_ERROR;
+ }
+
+ if (resolved != NULL && !oideq(&out_oid, want_oid)) {
+ return REFTABLE_LOCK_ERROR;
+ }
+
+ return 0;
+}
+
+static int ref_update_cmp(const void *a, const void *b)
+{
+ return strcmp((*(struct ref_update **)a)->refname,
+ (*(struct ref_update **)b)->refname);
+}
+
+static int write_transaction_table(struct reftable_writer *writer, void *arg)
+{
+ struct ref_transaction *transaction = (struct ref_transaction *)arg;
+ struct git_reftable_ref_store *refs =
+ (struct git_reftable_ref_store *)transaction->ref_store;
+ struct reftable_stack *stack =
+ stack_for(refs, transaction->updates[0]->refname);
+ uint64_t ts = reftable_stack_next_update_index(stack);
+ int err = 0;
+ int i = 0;
+ struct reftable_log_record *logs =
+ calloc(transaction->nr, sizeof(*logs));
+ struct ref_update **sorted =
+ malloc(transaction->nr * sizeof(struct ref_update *));
+ struct reftable_merged_table *mt = reftable_stack_merged_table(stack);
+ struct reftable_table tab = { NULL };
+ struct reftable_ref_record ref = { NULL };
+ reftable_table_from_merged_table(&tab, mt);
+ COPY_ARRAY(sorted, transaction->updates, transaction->nr);
+ QSORT(sorted, transaction->nr, ref_update_cmp);
+ reftable_writer_set_limits(writer, ts, ts);
+
+ for (i = 0; i < transaction->nr; i++) {
+ struct ref_update *u = sorted[i];
+ struct reftable_log_record *log = &logs[i];
+ struct object_id old_id = *null_oid();
+ fill_reftable_log_record(log);
+ log->update_index = ts;
+ log->value_type = REFTABLE_LOG_UPDATE;
+ log->refname = (char *)u->refname;
+ log->update.new_hash = u->new_oid.hash;
+ log->update.message = u->msg;
+
+ err = reftable_table_read_ref(&tab, u->refname, &ref);
+ if (err < 0)
+ goto done;
+ else if (err > 0) {
+ err = 0;
+ }
+
+ /* XXX if this is a symref (say, HEAD), should we deref the
+ * symref and check the update.old_hash against the referent? */
+ if (ref.value_type == REFTABLE_REF_VAL2 ||
+ ref.value_type == REFTABLE_REF_VAL1)
+ oidread(&old_id, ref.value.val1);
+
+ /* XXX fold together with the old_id check below? */
+
+ log->update.old_hash = old_id.hash;
+ if (u->flags & REF_LOG_ONLY) {
+ continue;
+ }
+
+ if (u->flags & REF_HAVE_NEW) {
+ struct reftable_ref_record ref = { NULL };
+ struct object_id peeled;
+
+ int peel_error = peel_object(&u->new_oid, &peeled);
+ ref.refname = (char *)u->refname;
+ ref.update_index = ts;
+
+ if (!peel_error) {
+ ref.value_type = REFTABLE_REF_VAL2;
+ ref.value.val2.target_value = peeled.hash;
+ ref.value.val2.value = u->new_oid.hash;
+ } else if (!is_null_oid(&u->new_oid)) {
+ ref.value_type = REFTABLE_REF_VAL1;
+ ref.value.val1 = u->new_oid.hash;
+ }
+
+ err = reftable_writer_add_ref(writer, &ref);
+ if (err < 0) {
+ goto done;
+ }
+ }
+ }
+
+ for (i = 0; i < transaction->nr; i++) {
+ err = reftable_writer_add_log(writer, &logs[i]);
+ clear_reftable_log_record(&logs[i]);
+ if (err < 0) {
+ goto done;
+ }
+ }
+
+done:
+ assert(err != REFTABLE_API_ERROR);
+ reftable_ref_record_release(&ref);
+ free(logs);
+ free(sorted);
+ return err;
+}
+
+static int git_reftable_transaction_finish(struct ref_store *ref_store,
+ struct ref_transaction *transaction,
+ struct strbuf *errmsg)
+{
+ struct reftable_addition *add =
+ (struct reftable_addition *)transaction->backend_data;
+ int err = 0;
+ int i;
+
+ for (i = 0; i < transaction->nr; i++) {
+ struct ref_update *u = transaction->updates[i];
+ if (u->flags & REF_HAVE_OLD) {
+ err = reftable_check_old_oid(transaction->ref_store,
+ u->refname, &u->old_oid);
+ if (err < 0) {
+ goto done;
+ }
+ }
+ }
+ if (transaction->nr) {
+ err = reftable_addition_add(add, &write_transaction_table,
+ transaction);
+ if (err < 0) {
+ goto done;
+ }
+ }
+
+ err = reftable_addition_commit(add);
+
+done:
+ assert(err != REFTABLE_API_ERROR);
+ reftable_addition_destroy(add);
+ transaction->state = REF_TRANSACTION_CLOSED;
+ transaction->backend_data = NULL;
+ if (err) {
+ strbuf_addf(errmsg, "reftable: transaction failure: %s",
+ reftable_error_str(err));
+ return -1;
+ }
+ return err;
+}
+
+static int
+git_reftable_transaction_initial_commit(struct ref_store *ref_store,
+ struct ref_transaction *transaction,
+ struct strbuf *errmsg)
+{
+ int err = git_reftable_transaction_prepare(ref_store, transaction,
+ errmsg);
+ if (err)
+ return err;
+
+ return git_reftable_transaction_finish(ref_store, transaction, errmsg);
+}
+
+struct write_delete_refs_arg {
+ struct reftable_stack *stack;
+ struct string_list *refnames;
+ const char *logmsg;
+ unsigned int flags;
+};
+
+static int write_delete_refs_table(struct reftable_writer *writer, void *argv)
+{
+ struct write_delete_refs_arg *arg =
+ (struct write_delete_refs_arg *)argv;
+ uint64_t ts = reftable_stack_next_update_index(arg->stack);
+ int err = 0;
+ int i = 0;
+
+ reftable_writer_set_limits(writer, ts, ts);
+ for (i = 0; i < arg->refnames->nr; i++) {
+ struct reftable_ref_record ref = {
+ .refname = (char *)arg->refnames->items[i].string,
+ .value_type = REFTABLE_REF_DELETION,
+ .update_index = ts,
+ };
+ err = reftable_writer_add_ref(writer, &ref);
+ if (err < 0) {
+ return err;
+ }
+ }
+
+ for (i = 0; i < arg->refnames->nr; i++) {
+ struct reftable_log_record log = {
+ .update_index = ts,
+ };
+ struct reftable_ref_record current = { NULL };
+ fill_reftable_log_record(&log);
+ log.update_index = ts;
+ log.refname = (char *)arg->refnames->items[i].string;
+
+ log.update.message = xstrdup(arg->logmsg);
+ log.update.new_hash = NULL;
+ log.update.old_hash = NULL;
+ if (reftable_stack_read_ref(arg->stack, log.refname,
+ &current) == 0) {
+ log.update.old_hash =
+ reftable_ref_record_val1(&current);
+ }
+ err = reftable_writer_add_log(writer, &log);
+ log.update.old_hash = NULL;
+ reftable_ref_record_release(&current);
+
+ clear_reftable_log_record(&log);
+ if (err < 0) {
+ return err;
+ }
+ }
+ return 0;
+}
+
+static int git_reftable_delete_refs(struct ref_store *ref_store,
+ const char *msg,
+ struct string_list *refnames,
+ unsigned int flags)
+{
+ struct git_reftable_ref_store *refs =
+ (struct git_reftable_ref_store *)ref_store;
+ struct reftable_stack *stack = stack_for(
+ refs, refnames->nr ? refnames->items[0].string : NULL);
+ struct write_delete_refs_arg arg = {
+ .stack = stack,
+ .refnames = refnames,
+ .logmsg = msg,
+ .flags = flags,
+ };
+ int err = refs->err;
+ if (err < 0) {
+ goto done;
+ }
+
+ string_list_sort(refnames);
+ err = reftable_stack_reload(stack);
+ if (err) {
+ goto done;
+ }
+ err = reftable_stack_add(stack, &write_delete_refs_table, &arg);
+done:
+ assert(err != REFTABLE_API_ERROR);
+ return err;
+}
+
+static int git_reftable_pack_refs(struct ref_store *ref_store,
+ unsigned int flags)
+{
+ struct git_reftable_ref_store *refs =
+ (struct git_reftable_ref_store *)ref_store;
+ int err = refs->err;
+ if (err < 0) {
+ return err;
+ }
+ err = reftable_stack_compact_all(refs->main_stack, NULL);
+ if (err == 0 && refs->worktree_stack != NULL)
+ err = reftable_stack_compact_all(refs->worktree_stack, NULL);
+ if (err == 0)
+ err = reftable_stack_clean(refs->main_stack);
+ if (err == 0 && refs->worktree_stack != NULL)
+ err = reftable_stack_clean(refs->worktree_stack);
+
+ return err;
+}
+
+struct write_create_symref_arg {
+ struct git_reftable_ref_store *refs;
+ struct reftable_stack *stack;
+ const char *refname;
+ const char *target;
+ const char *logmsg;
+};
+
+static int write_create_symref_table(struct reftable_writer *writer, void *arg)
+{
+ struct write_create_symref_arg *create =
+ (struct write_create_symref_arg *)arg;
+ uint64_t ts = reftable_stack_next_update_index(create->stack);
+ int err = 0;
+
+ struct reftable_ref_record ref = {
+ .refname = (char *)create->refname,
+ .value_type = REFTABLE_REF_SYMREF,
+ .value.symref = (char *)create->target,
+ .update_index = ts,
+ };
+ reftable_writer_set_limits(writer, ts, ts);
+ err = reftable_writer_add_ref(writer, &ref);
+ if (err == 0) {
+ struct reftable_log_record log = { NULL };
+ struct object_id new_oid;
+ struct object_id old_oid;
+
+ fill_reftable_log_record(&log);
+ log.refname = (char *)create->refname;
+ log.update_index = ts;
+ log.update.message = (char *)create->logmsg;
+ if (refs_resolve_ref_unsafe(
+ (struct ref_store *)create->refs, create->refname,
+ RESOLVE_REF_READING, &old_oid, NULL) != NULL) {
+ log.update.old_hash = old_oid.hash;
+ }
+
+ if (refs_resolve_ref_unsafe((struct ref_store *)create->refs,
+ create->target, RESOLVE_REF_READING,
+ &new_oid, NULL) != NULL) {
+ log.update.new_hash = new_oid.hash;
+ }
+
+ if (log.update.old_hash != NULL ||
+ log.update.new_hash != NULL) {
+ err = reftable_writer_add_log(writer, &log);
+ }
+ log.refname = NULL;
+ log.update.message = NULL;
+ log.update.old_hash = NULL;
+ log.update.new_hash = NULL;
+ clear_reftable_log_record(&log);
+ }
+ return err;
+}
+
+static int git_reftable_create_symref(struct ref_store *ref_store,
+ const char *refname, const char *target,
+ const char *logmsg)
+{
+ struct git_reftable_ref_store *refs =
+ (struct git_reftable_ref_store *)ref_store;
+ struct reftable_stack *stack = stack_for(refs, refname);
+ struct write_create_symref_arg arg = { .refs = refs,
+ .stack = stack,
+ .refname = refname,
+ .target = target,
+ .logmsg = logmsg };
+ int err = refs->err;
+ if (err < 0) {
+ goto done;
+ }
+ err = reftable_stack_reload(stack);
+ if (err) {
+ goto done;
+ }
+ err = reftable_stack_add(stack, &write_create_symref_table, &arg);
+done:
+ assert(err != REFTABLE_API_ERROR);
+ return err;
+}
+
+struct write_rename_arg {
+ struct reftable_stack *stack;
+ const char *oldname;
+ const char *newname;
+ const char *logmsg;
+};
+
+static int write_rename_table(struct reftable_writer *writer, void *argv)
+{
+ struct write_rename_arg *arg = (struct write_rename_arg *)argv;
+ uint64_t ts = reftable_stack_next_update_index(arg->stack);
+ struct reftable_ref_record old_ref = { NULL };
+ struct reftable_ref_record new_ref = { NULL };
+ int err = reftable_stack_read_ref(arg->stack, arg->oldname, &old_ref);
+
+ if (err) {
+ goto done;
+ }
+
+ /* git-branch supports a --force, but the check is not atomic. */
+ if (reftable_stack_read_ref(arg->stack, arg->newname, &new_ref) == 0) {
+ goto done;
+ }
+
+ reftable_writer_set_limits(writer, ts, ts);
+
+ {
+ struct reftable_ref_record todo[2] = {
+ {
+ .refname = (char *)arg->oldname,
+ .update_index = ts,
+ .value_type = REFTABLE_REF_DELETION,
+ },
+ old_ref,
+ };
+ todo[1].update_index = ts;
+ todo[1].refname = (char *)arg->newname;
+
+ err = reftable_writer_add_refs(writer, todo, 2);
+ if (err < 0) {
+ goto done;
+ }
+ }
+
+ if (reftable_ref_record_val1(&old_ref)) {
+ uint8_t *val1 = reftable_ref_record_val1(&old_ref);
+ struct reftable_log_record todo[2] = { { NULL } };
+ fill_reftable_log_record(&todo[0]);
+ fill_reftable_log_record(&todo[1]);
+
+ todo[0].refname = (char *)arg->oldname;
+ todo[0].update_index = ts;
+ todo[0].update.message = (char *)arg->logmsg;
+ todo[0].update.old_hash = val1;
+ todo[0].update.new_hash = NULL;
+
+ todo[1].refname = (char *)arg->newname;
+ todo[1].update_index = ts;
+ todo[1].update.old_hash = NULL;
+ todo[1].update.new_hash = val1;
+ todo[1].update.message = (char *)arg->logmsg;
+
+ err = reftable_writer_add_logs(writer, todo, 2);
+
+ clear_reftable_log_record(&todo[0]);
+ clear_reftable_log_record(&todo[1]);
+
+ if (err < 0) {
+ goto done;
+ }
+
+ } else {
+ /* XXX symrefs? */
+ }
+
+done:
+ assert(err != REFTABLE_API_ERROR);
+ reftable_ref_record_release(&new_ref);
+ reftable_ref_record_release(&old_ref);
+ return err;
+}
+
+static int write_copy_table(struct reftable_writer *writer, void *argv)
+{
+ struct write_rename_arg *arg = (struct write_rename_arg *)argv;
+ uint64_t ts = reftable_stack_next_update_index(arg->stack);
+ struct reftable_ref_record old_ref = { NULL };
+ struct reftable_ref_record new_ref = { NULL };
+ struct reftable_log_record log = { NULL };
+ struct reftable_iterator it = { NULL };
+ int err = reftable_stack_read_ref(arg->stack, arg->oldname, &old_ref);
+ if (err) {
+ goto done;
+ }
+
+ /* git-branch supports a --force, but the check is not atomic. */
+ if (reftable_stack_read_ref(arg->stack, arg->newname, &new_ref) == 0) {
+ goto done;
+ }
+
+ reftable_writer_set_limits(writer, ts, ts);
+
+ FREE_AND_NULL(old_ref.refname);
+ old_ref.refname = xstrdup(arg->newname);
+ old_ref.update_index = ts;
+ err = reftable_writer_add_ref(writer, &old_ref);
+ if (err < 0) {
+ goto done;
+ }
+
+ /* this copies the entire reflog history. Is this the right semantics?
+ */
+ /* XXX should clear out existing reflog entries for oldname? */
+ err = reftable_merged_table_seek_log(
+ reftable_stack_merged_table(arg->stack), &it, arg->oldname);
+ if (err < 0) {
+ goto done;
+ }
+ while (1) {
+ int err = reftable_iterator_next_log(&it, &log);
+ if (err < 0) {
+ goto done;
+ }
+
+ if (err > 0 || strcmp(log.refname, arg->oldname)) {
+ break;
+ }
+ FREE_AND_NULL(log.refname);
+ log.refname = xstrdup(arg->newname);
+ reftable_writer_add_log(writer, &log);
+ reftable_log_record_release(&log);
+ }
+
+done:
+ assert(err != REFTABLE_API_ERROR);
+ reftable_ref_record_release(&new_ref);
+ reftable_ref_record_release(&old_ref);
+ reftable_log_record_release(&log);
+ reftable_iterator_destroy(&it);
+ return err;
+}
+
+static int git_reftable_rename_ref(struct ref_store *ref_store,
+ const char *oldrefname,
+ const char *newrefname, const char *logmsg)
+{
+ struct git_reftable_ref_store *refs =
+ (struct git_reftable_ref_store *)ref_store;
+ struct reftable_stack *stack = stack_for(refs, newrefname);
+ struct write_rename_arg arg = {
+ .stack = stack,
+ .oldname = oldrefname,
+ .newname = newrefname,
+ .logmsg = logmsg,
+ };
+ int err = refs->err;
+ if (err < 0) {
+ goto done;
+ }
+ err = reftable_stack_reload(stack);
+ if (err) {
+ goto done;
+ }
+
+ err = reftable_stack_add(stack, &write_rename_table, &arg);
+done:
+ assert(err != REFTABLE_API_ERROR);
+ return err;
+}
+
+static int git_reftable_copy_ref(struct ref_store *ref_store,
+ const char *oldrefname, const char *newrefname,
+ const char *logmsg)
+{
+ struct git_reftable_ref_store *refs =
+ (struct git_reftable_ref_store *)ref_store;
+ struct reftable_stack *stack = stack_for(refs, newrefname);
+ struct write_rename_arg arg = {
+ .stack = stack,
+ .oldname = oldrefname,
+ .newname = newrefname,
+ .logmsg = logmsg,
+ };
+ int err = refs->err;
+ if (err < 0) {
+ goto done;
+ }
+ err = reftable_stack_reload(stack);
+ if (err) {
+ goto done;
+ }
+
+ err = reftable_stack_add(stack, &write_copy_table, &arg);
+done:
+ assert(err != REFTABLE_API_ERROR);
+ return err;
+}
+
+struct git_reftable_reflog_ref_iterator {
+ struct ref_iterator base;
+ struct reftable_iterator iter;
+ struct reftable_log_record log;
+ struct object_id oid;
+
+ /* Used when iterating over worktree & main */
+ struct reftable_merged_table *merged;
+ char *last_name;
+};
+
+static int
+git_reftable_reflog_ref_iterator_advance(struct ref_iterator *ref_iterator)
+{
+ struct git_reftable_reflog_ref_iterator *ri =
+ (struct git_reftable_reflog_ref_iterator *)ref_iterator;
+
+ while (1) {
+ int err = reftable_iterator_next_log(&ri->iter, &ri->log);
+ if (err > 0) {
+ return ITER_DONE;
+ }
+ if (err < 0) {
+ return ITER_ERROR;
+ }
+
+ ri->base.refname = ri->log.refname;
+ if (ri->last_name != NULL &&
+ !strcmp(ri->log.refname, ri->last_name)) {
+ /* we want the refnames that we have reflogs for, so we
+ * skip if we've already produced this name. This could
+ * be faster by seeking directly to
+ * reflog@update_index==0.
+ */
+ continue;
+ }
+
+ free(ri->last_name);
+ ri->last_name = xstrdup(ri->log.refname);
+ oidread(&ri->oid, ri->log.update.new_hash);
+ return ITER_OK;
+ }
+}
+
+static int
+git_reftable_reflog_ref_iterator_peel(struct ref_iterator *ref_iterator,
+ struct object_id *peeled)
+{
+ BUG("not supported.");
+ return -1;
+}
+
+static int
+git_reftable_reflog_ref_iterator_abort(struct ref_iterator *ref_iterator)
+{
+ struct git_reftable_reflog_ref_iterator *ri =
+ (struct git_reftable_reflog_ref_iterator *)ref_iterator;
+ reftable_log_record_release(&ri->log);
+ reftable_iterator_destroy(&ri->iter);
+ if (ri->merged)
+ reftable_merged_table_free(ri->merged);
+ return 0;
+}
+
+static struct ref_iterator_vtable git_reftable_reflog_ref_iterator_vtable = {
+ git_reftable_reflog_ref_iterator_advance,
+ git_reftable_reflog_ref_iterator_peel,
+ git_reftable_reflog_ref_iterator_abort
+};
+
+static struct ref_iterator *
+git_reftable_reflog_iterator_begin(struct ref_store *ref_store)
+{
+ struct git_reftable_reflog_ref_iterator *ri = xcalloc(1, sizeof(*ri));
+ struct git_reftable_ref_store *refs =
+ (struct git_reftable_ref_store *)ref_store;
+
+ if (refs->worktree_stack == NULL) {
+ struct reftable_stack *stack = refs->main_stack;
+ struct reftable_merged_table *mt =
+ reftable_stack_merged_table(stack);
+ int err = reftable_merged_table_seek_log(mt, &ri->iter, "");
+ if (err < 0) {
+ free(ri);
+ /* XXX is this allowed? */
+ return NULL;
+ }
+ } else {
+ struct reftable_merged_table *mt1 =
+ reftable_stack_merged_table(refs->main_stack);
+ struct reftable_merged_table *mt2 =
+ reftable_stack_merged_table(refs->worktree_stack);
+ struct reftable_table *tabs =
+ xcalloc(2, sizeof(struct reftable_table));
+ int err = 0;
+ reftable_table_from_merged_table(&tabs[0], mt1);
+ reftable_table_from_merged_table(&tabs[1], mt2);
+ err = reftable_new_merged_table(&ri->merged, tabs, 2,
+ the_hash_algo->format_id);
+ if (err < 0) {
+ free(tabs);
+ /* XXX see above */
+ return NULL;
+ }
+ err = reftable_merged_table_seek_ref(ri->merged, &ri->iter, "");
+ if (err < 0) {
+ return NULL;
+ }
+ }
+ base_ref_iterator_init(&ri->base,
+ &git_reftable_reflog_ref_iterator_vtable, 1);
+ ri->base.oid = &ri->oid;
+
+ return (struct ref_iterator *)ri;
+}
+
+static int git_reftable_for_each_reflog_ent_newest_first(
+ struct ref_store *ref_store, const char *refname, each_reflog_ent_fn fn,
+ void *cb_data)
+{
+ struct reftable_iterator it = { NULL };
+ struct git_reftable_ref_store *refs =
+ (struct git_reftable_ref_store *)ref_store;
+ struct reftable_stack *stack = stack_for(refs, refname);
+ struct reftable_merged_table *mt = NULL;
+ int err = 0;
+ struct reftable_log_record log = { NULL };
+
+ if (refs->err < 0) {
+ return refs->err;
+ }
+ refname = bare_ref_name(refname);
+
+ mt = reftable_stack_merged_table(stack);
+ err = reftable_merged_table_seek_log(mt, &it, refname);
+ while (err == 0) {
+ struct object_id old_oid;
+ struct object_id new_oid;
+ const char *full_committer = "";
+
+ err = reftable_iterator_next_log(&it, &log);
+ if (err > 0) {
+ err = 0;
+ break;
+ }
+ if (err < 0) {
+ break;
+ }
+
+ if (strcmp(log.refname, refname)) {
+ break;
+ }
+
+ oidread(&old_oid, log.update.old_hash);
+ oidread(&new_oid, log.update.new_hash);
+
+ full_committer = fmt_ident(log.update.name, log.update.email,
+ WANT_COMMITTER_IDENT,
+ /*date*/ NULL, IDENT_NO_DATE);
+ err = fn(&old_oid, &new_oid, full_committer, log.update.time,
+ log.update.tz_offset, log.update.message, cb_data);
+ if (err)
+ break;
+ }
+
+ reftable_log_record_release(&log);
+ reftable_iterator_destroy(&it);
+ return err;
+}
+
+static int git_reftable_for_each_reflog_ent_oldest_first(
+ struct ref_store *ref_store, const char *refname, each_reflog_ent_fn fn,
+ void *cb_data)
+{
+ struct reftable_iterator it = { NULL };
+ struct git_reftable_ref_store *refs =
+ (struct git_reftable_ref_store *)ref_store;
+ struct reftable_stack *stack = stack_for(refs, refname);
+ struct reftable_merged_table *mt = NULL;
+ struct reftable_log_record *logs = NULL;
+ int cap = 0;
+ int len = 0;
+ int err = 0;
+ int i = 0;
+
+ if (refs->err < 0) {
+ return refs->err;
+ }
+ refname = bare_ref_name(refname);
+ mt = reftable_stack_merged_table(stack);
+ err = reftable_merged_table_seek_log(mt, &it, refname);
+
+ while (err == 0) {
+ struct reftable_log_record log = { NULL };
+ err = reftable_iterator_next_log(&it, &log);
+ if (err > 0) {
+ err = 0;
+ break;
+ }
+ if (err < 0) {
+ break;
+ }
+
+ if (strcmp(log.refname, refname)) {
+ break;
+ }
+
+ if (len == cap) {
+ cap = 2 * cap + 1;
+ logs = realloc(logs, cap * sizeof(*logs));
+ }
+
+ logs[len++] = log;
+ }
+
+ for (i = len; i--;) {
+ struct reftable_log_record *log = &logs[i];
+ struct object_id old_oid;
+ struct object_id new_oid;
+ const char *full_committer = "";
+
+ oidread(&old_oid, log->update.old_hash);
+ oidread(&new_oid, log->update.new_hash);
+
+ full_committer = fmt_ident(log->update.name, log->update.email,
+ WANT_COMMITTER_IDENT, NULL,
+ IDENT_NO_DATE);
+ err = fn(&old_oid, &new_oid, full_committer, log->update.time,
+ log->update.tz_offset, log->update.message, cb_data);
+ if (err) {
+ break;
+ }
+ }
+
+ for (i = 0; i < len; i++) {
+ reftable_log_record_release(&logs[i]);
+ }
+ free(logs);
+
+ reftable_iterator_destroy(&it);
+ return err;
+}
+
+static int git_reftable_reflog_exists(struct ref_store *ref_store,
+ const char *refname)
+{
+ struct reftable_iterator it = { NULL };
+ struct git_reftable_ref_store *refs =
+ (struct git_reftable_ref_store *)ref_store;
+ struct reftable_stack *stack = stack_for(refs, refname);
+ struct reftable_merged_table *mt = reftable_stack_merged_table(stack);
+ struct reftable_log_record log = { NULL };
+ int err = refs->err;
+
+ if (err < 0) {
+ goto done;
+ }
+
+ refname = bare_ref_name(refname);
+ err = reftable_merged_table_seek_log(mt, &it, refname);
+ if (err) {
+ goto done;
+ }
+ err = reftable_iterator_next_log(&it, &log);
+ if (err) {
+ goto done;
+ }
+
+ if (strcmp(log.refname, refname)) {
+ err = 1;
+ }
+
+done:
+ reftable_iterator_destroy(&it);
+ reftable_log_record_release(&log);
+ return !err;
+}
+
+static int git_reftable_create_reflog(struct ref_store *ref_store,
+ const char *refname, int force_create,
+ struct strbuf *err)
+{
+ return 0;
+}
+
+struct write_reflog_delete_arg {
+ struct reftable_stack *stack;
+ const char *refname;
+};
+
+static int write_reflog_delete_table(struct reftable_writer *writer, void *argv)
+{
+ struct write_reflog_delete_arg *arg = argv;
+ struct reftable_merged_table *mt =
+ reftable_stack_merged_table(arg->stack);
+ struct reftable_log_record log = { NULL };
+ struct reftable_iterator it = { NULL };
+ uint64_t ts = reftable_stack_next_update_index(arg->stack);
+ int err = reftable_merged_table_seek_log(mt, &it, arg->refname);
+
+ reftable_writer_set_limits(writer, ts, ts);
+ while (err == 0) {
+ struct reftable_log_record tombstone = {
+ .refname = (char *)arg->refname,
+ .update_index = REFTABLE_LOG_DELETION,
+ };
+ err = reftable_iterator_next_log(&it, &log);
+ if (err > 0) {
+ err = 0;
+ break;
+ }
+
+ if (err < 0 || strcmp(log.refname, arg->refname)) {
+ break;
+ }
+ tombstone.update_index = log.update_index;
+ err = reftable_writer_add_log(writer, &tombstone);
+ }
+
+ return err;
+}
+
+static int git_reftable_delete_reflog(struct ref_store *ref_store,
+ const char *refname)
+{
+ struct git_reftable_ref_store *refs =
+ (struct git_reftable_ref_store *)ref_store;
+ struct reftable_stack *stack = stack_for(refs, refname);
+ struct write_reflog_delete_arg arg = {
+ .stack = stack,
+ .refname = refname,
+ };
+ int err = reftable_stack_add(stack, &write_reflog_delete_table, &arg);
+ assert(err != REFTABLE_API_ERROR);
+ return err;
+}
+
+struct reflog_expiry_arg {
+ struct reftable_stack *stack;
+ struct reftable_log_record *records;
+ int len;
+};
+
+static int write_reflog_expiry_table(struct reftable_writer *writer, void *argv)
+{
+ struct reflog_expiry_arg *arg = (struct reflog_expiry_arg *)argv;
+ uint64_t ts = reftable_stack_next_update_index(arg->stack);
+ int i = 0;
+ reftable_writer_set_limits(writer, ts, ts);
+ for (i = 0; i < arg->len; i++) {
+ int err = reftable_writer_add_log(writer, &arg->records[i]);
+ if (err) {
+ return err;
+ }
+ }
+ return 0;
+}
+
+static int
+git_reftable_reflog_expire(struct ref_store *ref_store, const char *refname,
+ const struct object_id *oid, unsigned int flags,
+ reflog_expiry_prepare_fn prepare_fn,
+ reflog_expiry_should_prune_fn should_prune_fn,
+ reflog_expiry_cleanup_fn cleanup_fn,
+ void *policy_cb_data)
+{
+ /*
+ For log expiry, we write tombstones in place of the expired entries,
+ This means that the entries are still retrievable by delving into the
+ stack, and expiring entries paradoxically takes extra memory.
+
+ This memory is only reclaimed when some operation issues a
+ git_reftable_pack_refs(), which will compact the entire stack and get
+ rid of deletion entries.
+
+ It would be better if the refs backend supported an API that sets a
+ criterion for all refs, passing the criterion to pack_refs().
+ */
+ struct git_reftable_ref_store *refs =
+ (struct git_reftable_ref_store *)ref_store;
+ struct reftable_stack *stack = stack_for(refs, refname);
+ struct reftable_merged_table *mt = NULL;
+ struct reflog_expiry_arg arg = {
+ .stack = stack,
+ };
+ struct reftable_log_record *logs = NULL;
+ struct reftable_log_record *rewritten = NULL;
+ int logs_len = 0;
+ int logs_cap = 0;
+ int i = 0;
+ uint8_t *last_hash = NULL;
+ struct reftable_iterator it = { NULL };
+ struct reftable_addition *add = NULL;
+ int err = 0;
+ if (refs->err < 0) {
+ return refs->err;
+ }
+ err = reftable_stack_reload(stack);
+ if (err) {
+ goto done;
+ }
+
+ mt = reftable_stack_merged_table(stack);
+ err = reftable_merged_table_seek_log(mt, &it, refname);
+ if (err < 0) {
+ goto done;
+ }
+
+ err = reftable_stack_new_addition(&add, stack);
+ if (err) {
+ goto done;
+ }
+ prepare_fn(refname, oid, policy_cb_data);
+ while (1) {
+ struct reftable_log_record log = { NULL };
+ int err = reftable_iterator_next_log(&it, &log);
+ if (err < 0) {
+ goto done;
+ }
+
+ if (err > 0 || strcmp(log.refname, refname)) {
+ break;
+ }
+
+ if (logs_len >= logs_cap) {
+ int new_cap = logs_cap * 2 + 1;
+ logs = realloc(logs, new_cap * sizeof(*logs));
+ logs_cap = new_cap;
+ }
+ logs[logs_len++] = log;
+ }
+
+ rewritten = calloc(logs_len, sizeof(*rewritten));
+ for (i = logs_len - 1; i >= 0; i--) {
+ struct object_id ooid;
+ struct object_id noid;
+ struct reftable_log_record *dest = &rewritten[i];
+
+ *dest = logs[i];
+ oidread(&ooid, logs[i].update.old_hash);
+ oidread(&noid, logs[i].update.new_hash);
+
+ if (should_prune_fn(&ooid, &noid, logs[i].update.email,
+ (timestamp_t)logs[i].update.time,
+ logs[i].update.tz_offset,
+ logs[i].update.message, policy_cb_data)) {
+ dest->value_type = REFTABLE_LOG_DELETION;
+ } else {
+ if ((flags & EXPIRE_REFLOGS_REWRITE) &&
+ last_hash != NULL) {
+ dest->update.old_hash = last_hash;
+ }
+ last_hash = logs[i].update.new_hash;
+ }
+ }
+
+ arg.records = rewritten;
+ arg.len = logs_len;
+ err = reftable_addition_add(add, &write_reflog_expiry_table, &arg);
+ if (err < 0) {
+ goto done;
+ }
+
+ if (!(flags & EXPIRE_REFLOGS_DRY_RUN)) {
+ /* XXX - skip writing records that were not changed. */
+ err = reftable_addition_commit(add);
+ } else {
+ /* XXX - print something */
+ }
+
+done:
+ if (add) {
+ cleanup_fn(policy_cb_data);
+ }
+ assert(err != REFTABLE_API_ERROR);
+ reftable_addition_destroy(add);
+ for (i = 0; i < logs_len; i++)
+ reftable_log_record_release(&logs[i]);
+ free(logs);
+ free(rewritten);
+ reftable_iterator_destroy(&it);
+ return err;
+}
+
+static int git_reftable_read_raw_ref(struct ref_store *ref_store,
+ const char *refname, struct object_id *oid,
+ struct strbuf *referent,
+ unsigned int *type, int *failure_errno)
+{
+ struct git_reftable_ref_store *refs =
+ (struct git_reftable_ref_store *)ref_store;
+ struct reftable_stack *stack = stack_for(refs, refname);
+ struct reftable_ref_record ref = { NULL };
+ int err = 0;
+
+ refname = bare_ref_name(refname); /* XXX - in which other cases should
+ we do this? */
+ if (refs->err < 0) {
+ return refs->err;
+ }
+
+ /* This is usually not needed, but Git doesn't signal to ref backend if
+ a subprocess updated the ref DB. So we always check.
+ */
+ err = reftable_stack_reload(stack);
+ if (err) {
+ goto done;
+ }
+
+ err = reftable_stack_read_ref(stack, refname, &ref);
+ if (err > 0) {
+ *failure_errno = ENOENT;
+ err = -1;
+ goto done;
+ }
+ if (err < 0) {
+ goto done;
+ }
+
+ if (ref.value_type == REFTABLE_REF_SYMREF) {
+ strbuf_reset(referent);
+ strbuf_addstr(referent, ref.value.symref);
+ *type |= REF_ISSYMREF;
+ } else if (reftable_ref_record_val1(&ref) != NULL) {
+ oidread(oid, reftable_ref_record_val1(&ref));
+ } else {
+ /* We got a tombstone, which should not happen. */
+ BUG("Got reftable_ref_record with value type %d",
+ ref.value_type);
+ }
+
+done:
+ assert(err != REFTABLE_API_ERROR);
+ reftable_ref_record_release(&ref);
+ return err;
+}
+
+struct ref_storage_be refs_be_reftable = {
+ &refs_be_files,
+ "reftable",
+ git_reftable_ref_store_create,
+ git_reftable_init_db,
+ git_reftable_transaction_prepare,
+ git_reftable_transaction_finish,
+ git_reftable_transaction_abort,
+ git_reftable_transaction_initial_commit,
+
+ git_reftable_pack_refs,
+ git_reftable_create_symref,
+ git_reftable_delete_refs,
+ git_reftable_rename_ref,
+ git_reftable_copy_ref,
+
+ git_reftable_ref_iterator_begin,
+ git_reftable_read_raw_ref,
+
+ git_reftable_reflog_iterator_begin,
+ git_reftable_for_each_reflog_ent_oldest_first,
+ git_reftable_for_each_reflog_ent_newest_first,
+ git_reftable_reflog_exists,
+ git_reftable_create_reflog,
+ git_reftable_delete_reflog,
+ git_reftable_reflog_expire,
+};
diff --git a/reftable/LICENSE b/reftable/LICENSE
new file mode 100644
index 0000000..402e0f9
--- /dev/null
+++ b/reftable/LICENSE
@@ -0,0 +1,31 @@
+BSD License
+
+Copyright (c) 2020, Google LLC
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+* Redistributions of source code must retain the above copyright notice,
+this list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright
+notice, this list of conditions and the following disclaimer in the
+documentation and/or other materials provided with the distribution.
+
+* Neither the name of Google LLC nor the names of its contributors may
+be used to endorse or promote products derived from this software
+without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/reftable/basics.c b/reftable/basics.c
new file mode 100644
index 0000000..f761e48
--- /dev/null
+++ b/reftable/basics.c
@@ -0,0 +1,128 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "basics.h"
+
+void put_be24(uint8_t *out, uint32_t i)
+{
+ out[0] = (uint8_t)((i >> 16) & 0xff);
+ out[1] = (uint8_t)((i >> 8) & 0xff);
+ out[2] = (uint8_t)(i & 0xff);
+}
+
+uint32_t get_be24(uint8_t *in)
+{
+ return (uint32_t)(in[0]) << 16 | (uint32_t)(in[1]) << 8 |
+ (uint32_t)(in[2]);
+}
+
+void put_be16(uint8_t *out, uint16_t i)
+{
+ out[0] = (uint8_t)((i >> 8) & 0xff);
+ out[1] = (uint8_t)(i & 0xff);
+}
+
+int binsearch(size_t sz, int (*f)(size_t k, void *args), void *args)
+{
+ size_t lo = 0;
+ size_t hi = sz;
+
+ /* Invariants:
+ *
+ * (hi == sz) || f(hi) == true
+ * (lo == 0 && f(0) == true) || fi(lo) == false
+ */
+ while (hi - lo > 1) {
+ size_t mid = lo + (hi - lo) / 2;
+
+ if (f(mid, args))
+ hi = mid;
+ else
+ lo = mid;
+ }
+
+ if (lo)
+ return hi;
+
+ return f(0, args) ? 0 : 1;
+}
+
+void free_names(char **a)
+{
+ char **p;
+ if (!a) {
+ return;
+ }
+ for (p = a; *p; p++) {
+ reftable_free(*p);
+ }
+ reftable_free(a);
+}
+
+int names_length(char **names)
+{
+ char **p = names;
+ for (; *p; p++) {
+ /* empty */
+ }
+ return p - names;
+}
+
+void parse_names(char *buf, int size, char ***namesp)
+{
+ char **names = NULL;
+ size_t names_cap = 0;
+ size_t names_len = 0;
+
+ char *p = buf;
+ char *end = buf + size;
+ while (p < end) {
+ char *next = strchr(p, '\n');
+ if (next && next < end) {
+ *next = 0;
+ } else {
+ next = end;
+ }
+ if (p < next) {
+ if (names_len == names_cap) {
+ names_cap = 2 * names_cap + 1;
+ names = reftable_realloc(
+ names, names_cap * sizeof(*names));
+ }
+ names[names_len++] = xstrdup(p);
+ }
+ p = next + 1;
+ }
+
+ names = reftable_realloc(names, (names_len + 1) * sizeof(*names));
+ names[names_len] = NULL;
+ *namesp = names;
+}
+
+int names_equal(char **a, char **b)
+{
+ int i = 0;
+ for (; a[i] && b[i]; i++) {
+ if (strcmp(a[i], b[i])) {
+ return 0;
+ }
+ }
+
+ return a[i] == b[i];
+}
+
+int common_prefix_size(struct strbuf *a, struct strbuf *b)
+{
+ int p = 0;
+ for (; p < a->len && p < b->len; p++) {
+ if (a->buf[p] != b->buf[p])
+ break;
+ }
+
+ return p;
+}
diff --git a/reftable/basics.h b/reftable/basics.h
new file mode 100644
index 0000000..096b368
--- /dev/null
+++ b/reftable/basics.h
@@ -0,0 +1,60 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef BASICS_H
+#define BASICS_H
+
+/*
+ * miscellaneous utilities that are not provided by Git.
+ */
+
+#include "system.h"
+
+/* Bigendian en/decoding of integers */
+
+void put_be24(uint8_t *out, uint32_t i);
+uint32_t get_be24(uint8_t *in);
+void put_be16(uint8_t *out, uint16_t i);
+
+/*
+ * find smallest index i in [0, sz) at which f(i) is true, assuming
+ * that f is ascending. Return sz if f(i) is false for all indices.
+ *
+ * Contrary to bsearch(3), this returns something useful if the argument is not
+ * found.
+ */
+int binsearch(size_t sz, int (*f)(size_t k, void *args), void *args);
+
+/*
+ * Frees a NULL terminated array of malloced strings. The array itself is also
+ * freed.
+ */
+void free_names(char **a);
+
+/* parse a newline separated list of names. `size` is the length of the buffer,
+ * without terminating '\0'. Empty names are discarded. */
+void parse_names(char *buf, int size, char ***namesp);
+
+/* compares two NULL-terminated arrays of strings. */
+int names_equal(char **a, char **b);
+
+/* returns the array size of a NULL-terminated array of strings. */
+int names_length(char **names);
+
+/* Allocation routines; they invoke the functions set through
+ * reftable_set_alloc() */
+void *reftable_malloc(size_t sz);
+void *reftable_realloc(void *p, size_t sz);
+void reftable_free(void *p);
+void *reftable_calloc(size_t sz);
+
+/* Find the longest shared prefix size of `a` and `b` */
+struct strbuf;
+int common_prefix_size(struct strbuf *a, struct strbuf *b);
+
+#endif
diff --git a/reftable/basics_test.c b/reftable/basics_test.c
new file mode 100644
index 0000000..1fcd229
--- /dev/null
+++ b/reftable/basics_test.c
@@ -0,0 +1,98 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "system.h"
+
+#include "basics.h"
+#include "test_framework.h"
+#include "reftable-tests.h"
+
+struct binsearch_args {
+ int key;
+ int *arr;
+};
+
+static int binsearch_func(size_t i, void *void_args)
+{
+ struct binsearch_args *args = void_args;
+
+ return args->key < args->arr[i];
+}
+
+static void test_binsearch(void)
+{
+ int arr[] = { 2, 4, 6, 8, 10 };
+ size_t sz = ARRAY_SIZE(arr);
+ struct binsearch_args args = {
+ .arr = arr,
+ };
+
+ int i = 0;
+ for (i = 1; i < 11; i++) {
+ int res;
+ args.key = i;
+ res = binsearch(sz, &binsearch_func, &args);
+
+ if (res < sz) {
+ EXPECT(args.key < arr[res]);
+ if (res > 0) {
+ EXPECT(args.key >= arr[res - 1]);
+ }
+ } else {
+ EXPECT(args.key == 10 || args.key == 11);
+ }
+ }
+}
+
+static void test_names_length(void)
+{
+ char *a[] = { "a", "b", NULL };
+ EXPECT(names_length(a) == 2);
+}
+
+static void test_parse_names_normal(void)
+{
+ char in[] = "a\nb\n";
+ char **out = NULL;
+ parse_names(in, strlen(in), &out);
+ EXPECT(!strcmp(out[0], "a"));
+ EXPECT(!strcmp(out[1], "b"));
+ EXPECT(!out[2]);
+ free_names(out);
+}
+
+static void test_parse_names_drop_empty(void)
+{
+ char in[] = "a\n\n";
+ char **out = NULL;
+ parse_names(in, strlen(in), &out);
+ EXPECT(!strcmp(out[0], "a"));
+ EXPECT(!out[1]);
+ free_names(out);
+}
+
+static void test_common_prefix(void)
+{
+ struct strbuf s1 = STRBUF_INIT;
+ struct strbuf s2 = STRBUF_INIT;
+ strbuf_addstr(&s1, "abcdef");
+ strbuf_addstr(&s2, "abc");
+ EXPECT(common_prefix_size(&s1, &s2) == 3);
+ strbuf_release(&s1);
+ strbuf_release(&s2);
+}
+
+int basics_test_main(int argc, const char *argv[])
+{
+ RUN_TEST(test_common_prefix);
+ RUN_TEST(test_parse_names_normal);
+ RUN_TEST(test_parse_names_drop_empty);
+ RUN_TEST(test_binsearch);
+ RUN_TEST(test_names_length);
+ return 0;
+}
diff --git a/reftable/block.c b/reftable/block.c
new file mode 100644
index 0000000..92f8e5a
--- /dev/null
+++ b/reftable/block.c
@@ -0,0 +1,446 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "block.h"
+
+#include "blocksource.h"
+#include "constants.h"
+#include "record.h"
+#include "reftable-error.h"
+#include "system.h"
+#include <zlib.h>
+
+#ifdef NO_UNCOMPRESS2
+/* This is uncompress2, which is only available in zlib as of 2017.
+ */
+int uncompress2(Bytef *dest, uLongf *destLen, const Bytef *source,
+ uLong *sourceLen);
+#endif
+
+int header_size(int version)
+{
+ switch (version) {
+ case 1:
+ return 24;
+ case 2:
+ return 28;
+ }
+ abort();
+}
+
+int footer_size(int version)
+{
+ switch (version) {
+ case 1:
+ return 68;
+ case 2:
+ return 72;
+ }
+ abort();
+}
+
+static int block_writer_register_restart(struct block_writer *w, int n,
+ int is_restart, struct strbuf *key)
+{
+ int rlen = w->restart_len;
+ if (rlen >= MAX_RESTARTS) {
+ is_restart = 0;
+ }
+
+ if (is_restart) {
+ rlen++;
+ }
+ if (2 + 3 * rlen + n > w->block_size - w->next)
+ return -1;
+ if (is_restart) {
+ if (w->restart_len == w->restart_cap) {
+ w->restart_cap = w->restart_cap * 2 + 1;
+ w->restarts = reftable_realloc(
+ w->restarts, sizeof(uint32_t) * w->restart_cap);
+ }
+
+ w->restarts[w->restart_len++] = w->next;
+ }
+
+ w->next += n;
+
+ strbuf_reset(&w->last_key);
+ strbuf_addbuf(&w->last_key, key);
+ w->entries++;
+ return 0;
+}
+
+void block_writer_init(struct block_writer *bw, uint8_t typ, uint8_t *buf,
+ uint32_t block_size, uint32_t header_off, int hash_size)
+{
+ bw->buf = buf;
+ bw->hash_size = hash_size;
+ bw->block_size = block_size;
+ bw->header_off = header_off;
+ bw->buf[header_off] = typ;
+ bw->next = header_off + 4;
+ bw->restart_interval = 16;
+ bw->entries = 0;
+ bw->restart_len = 0;
+ bw->last_key.len = 0;
+}
+
+uint8_t block_writer_type(struct block_writer *bw)
+{
+ return bw->buf[bw->header_off];
+}
+
+/* adds the reftable_record to the block. Returns -1 if it does not fit, 0 on
+ success */
+int block_writer_add(struct block_writer *w, struct reftable_record *rec)
+{
+ struct strbuf empty = STRBUF_INIT;
+ struct strbuf last =
+ w->entries % w->restart_interval == 0 ? empty : w->last_key;
+ struct string_view out = {
+ .buf = w->buf + w->next,
+ .len = w->block_size - w->next,
+ };
+
+ struct string_view start = out;
+
+ int is_restart = 0;
+ struct strbuf key = STRBUF_INIT;
+ int n = 0;
+
+ reftable_record_key(rec, &key);
+ n = reftable_encode_key(&is_restart, out, last, key,
+ reftable_record_val_type(rec));
+ if (n < 0)
+ goto done;
+ string_view_consume(&out, n);
+
+ n = reftable_record_encode(rec, out, w->hash_size);
+ if (n < 0)
+ goto done;
+ string_view_consume(&out, n);
+
+ if (block_writer_register_restart(w, start.len - out.len, is_restart,
+ &key) < 0)
+ goto done;
+
+ strbuf_release(&key);
+ return 0;
+
+done:
+ strbuf_release(&key);
+ return -1;
+}
+
+int block_writer_finish(struct block_writer *w)
+{
+ int i = 0;
+ for (i = 0; i < w->restart_len; i++) {
+ put_be24(w->buf + w->next, w->restarts[i]);
+ w->next += 3;
+ }
+
+ put_be16(w->buf + w->next, w->restart_len);
+ w->next += 2;
+ put_be24(w->buf + 1 + w->header_off, w->next);
+
+ if (block_writer_type(w) == BLOCK_TYPE_LOG) {
+ int block_header_skip = 4 + w->header_off;
+ uint8_t *compressed = NULL;
+ int zresult = 0;
+ uLongf src_len = w->next - block_header_skip;
+ size_t dest_cap = src_len;
+
+ compressed = reftable_malloc(dest_cap);
+ while (1) {
+ uLongf out_dest_len = dest_cap;
+
+ zresult = compress2(compressed, &out_dest_len,
+ w->buf + block_header_skip, src_len,
+ 9);
+ if (zresult == Z_BUF_ERROR) {
+ dest_cap *= 2;
+ compressed =
+ reftable_realloc(compressed, dest_cap);
+ continue;
+ }
+
+ if (Z_OK != zresult) {
+ reftable_free(compressed);
+ return REFTABLE_ZLIB_ERROR;
+ }
+
+ memcpy(w->buf + block_header_skip, compressed,
+ out_dest_len);
+ w->next = out_dest_len + block_header_skip;
+ reftable_free(compressed);
+ break;
+ }
+ }
+ return w->next;
+}
+
+uint8_t block_reader_type(struct block_reader *r)
+{
+ return r->block.data[r->header_off];
+}
+
+int block_reader_init(struct block_reader *br, struct reftable_block *block,
+ uint32_t header_off, uint32_t table_block_size,
+ int hash_size)
+{
+ uint32_t full_block_size = table_block_size;
+ uint8_t typ = block->data[header_off];
+ uint32_t sz = get_be24(block->data + header_off + 1);
+
+ uint16_t restart_count = 0;
+ uint32_t restart_start = 0;
+ uint8_t *restart_bytes = NULL;
+
+ if (!reftable_is_block_type(typ))
+ return REFTABLE_FORMAT_ERROR;
+
+ if (typ == BLOCK_TYPE_LOG) {
+ int block_header_skip = 4 + header_off;
+ uLongf dst_len = sz - block_header_skip; /* total size of dest
+ buffer. */
+ uLongf src_len = block->len - block_header_skip;
+ /* Log blocks specify the *uncompressed* size in their header.
+ */
+ uint8_t *uncompressed = reftable_malloc(sz);
+
+ /* Copy over the block header verbatim. It's not compressed. */
+ memcpy(uncompressed, block->data, block_header_skip);
+
+ /* Uncompress */
+ if (Z_OK !=
+ uncompress2(uncompressed + block_header_skip, &dst_len,
+ block->data + block_header_skip, &src_len)) {
+ reftable_free(uncompressed);
+ return REFTABLE_ZLIB_ERROR;
+ }
+
+ if (dst_len + block_header_skip != sz)
+ return REFTABLE_FORMAT_ERROR;
+
+ /* We're done with the input data. */
+ reftable_block_done(block);
+ block->data = uncompressed;
+ block->len = sz;
+ block->source = malloc_block_source();
+ full_block_size = src_len + block_header_skip;
+ } else if (full_block_size == 0) {
+ full_block_size = sz;
+ } else if (sz < full_block_size && sz < block->len &&
+ block->data[sz] != 0) {
+ /* If the block is smaller than the full block size, it is
+ padded (data followed by '\0') or the next block is
+ unaligned. */
+ full_block_size = sz;
+ }
+
+ restart_count = get_be16(block->data + sz - 2);
+ restart_start = sz - 2 - 3 * restart_count;
+ restart_bytes = block->data + restart_start;
+
+ /* transfer ownership. */
+ br->block = *block;
+ block->data = NULL;
+ block->len = 0;
+
+ br->hash_size = hash_size;
+ br->block_len = restart_start;
+ br->full_block_size = full_block_size;
+ br->header_off = header_off;
+ br->restart_count = restart_count;
+ br->restart_bytes = restart_bytes;
+
+ return 0;
+}
+
+static uint32_t block_reader_restart_offset(struct block_reader *br, int i)
+{
+ return get_be24(br->restart_bytes + 3 * i);
+}
+
+void block_reader_start(struct block_reader *br, struct block_iter *it)
+{
+ it->br = br;
+ strbuf_reset(&it->last_key);
+ it->next_off = br->header_off + 4;
+}
+
+struct restart_find_args {
+ int error;
+ struct strbuf key;
+ struct block_reader *r;
+};
+
+static int restart_key_less(size_t idx, void *args)
+{
+ struct restart_find_args *a = args;
+ uint32_t off = block_reader_restart_offset(a->r, idx);
+ struct string_view in = {
+ .buf = a->r->block.data + off,
+ .len = a->r->block_len - off,
+ };
+
+ /* the restart key is verbatim in the block, so this could avoid the
+ alloc for decoding the key */
+ struct strbuf rkey = STRBUF_INIT;
+ struct strbuf last_key = STRBUF_INIT;
+ uint8_t unused_extra;
+ int n = reftable_decode_key(&rkey, &unused_extra, last_key, in);
+ int result;
+ if (n < 0) {
+ a->error = 1;
+ return -1;
+ }
+
+ result = strbuf_cmp(&a->key, &rkey);
+ strbuf_release(&rkey);
+ return result;
+}
+
+void block_iter_copy_from(struct block_iter *dest, struct block_iter *src)
+{
+ dest->br = src->br;
+ dest->next_off = src->next_off;
+ strbuf_reset(&dest->last_key);
+ strbuf_addbuf(&dest->last_key, &src->last_key);
+}
+
+int block_iter_next(struct block_iter *it, struct reftable_record *rec)
+{
+ struct string_view in = {
+ .buf = it->br->block.data + it->next_off,
+ .len = it->br->block_len - it->next_off,
+ };
+ struct string_view start = in;
+ struct strbuf key = STRBUF_INIT;
+ uint8_t extra = 0;
+ int n = 0;
+
+ if (it->next_off >= it->br->block_len)
+ return 1;
+
+ n = reftable_decode_key(&key, &extra, it->last_key, in);
+ if (n < 0)
+ return -1;
+
+ string_view_consume(&in, n);
+ n = reftable_record_decode(rec, key, extra, in, it->br->hash_size);
+ if (n < 0)
+ return -1;
+ string_view_consume(&in, n);
+
+ strbuf_reset(&it->last_key);
+ strbuf_addbuf(&it->last_key, &key);
+ it->next_off += start.len - in.len;
+ strbuf_release(&key);
+ return 0;
+}
+
+int block_reader_first_key(struct block_reader *br, struct strbuf *key)
+{
+ struct strbuf empty = STRBUF_INIT;
+ int off = br->header_off + 4;
+ struct string_view in = {
+ .buf = br->block.data + off,
+ .len = br->block_len - off,
+ };
+
+ uint8_t extra = 0;
+ int n = reftable_decode_key(key, &extra, empty, in);
+ if (n < 0)
+ return n;
+
+ return 0;
+}
+
+int block_iter_seek(struct block_iter *it, struct strbuf *want)
+{
+ return block_reader_seek(it->br, it, want);
+}
+
+void block_iter_close(struct block_iter *it)
+{
+ strbuf_release(&it->last_key);
+}
+
+int block_reader_seek(struct block_reader *br, struct block_iter *it,
+ struct strbuf *want)
+{
+ struct restart_find_args args = {
+ .key = *want,
+ .r = br,
+ };
+ struct reftable_record rec = reftable_new_record(block_reader_type(br));
+ struct strbuf key = STRBUF_INIT;
+ int err = 0;
+ struct block_iter next = {
+ .last_key = STRBUF_INIT,
+ };
+
+ int i = binsearch(br->restart_count, &restart_key_less, &args);
+ if (args.error) {
+ err = REFTABLE_FORMAT_ERROR;
+ goto done;
+ }
+
+ it->br = br;
+ if (i > 0) {
+ i--;
+ it->next_off = block_reader_restart_offset(br, i);
+ } else {
+ it->next_off = br->header_off + 4;
+ }
+
+ /* We're looking for the last entry less/equal than the wanted key, so
+ we have to go one entry too far and then back up.
+ */
+ while (1) {
+ block_iter_copy_from(&next, it);
+ err = block_iter_next(&next, &rec);
+ if (err < 0)
+ goto done;
+
+ reftable_record_key(&rec, &key);
+ if (err > 0 || strbuf_cmp(&key, want) >= 0) {
+ err = 0;
+ goto done;
+ }
+
+ block_iter_copy_from(it, &next);
+ }
+
+done:
+ strbuf_release(&key);
+ strbuf_release(&next.last_key);
+ reftable_record_destroy(&rec);
+
+ return err;
+}
+
+void block_writer_release(struct block_writer *bw)
+{
+ FREE_AND_NULL(bw->restarts);
+ strbuf_release(&bw->last_key);
+ /* the block is not owned. */
+}
+
+void reftable_block_done(struct reftable_block *blockp)
+{
+ struct reftable_block_source source = blockp->source;
+ if (blockp && source.ops)
+ source.ops->return_block(source.arg, blockp);
+ blockp->data = NULL;
+ blockp->len = 0;
+ blockp->source.ops = NULL;
+ blockp->source.arg = NULL;
+}
diff --git a/reftable/block.h b/reftable/block.h
new file mode 100644
index 0000000..e207706
--- /dev/null
+++ b/reftable/block.h
@@ -0,0 +1,127 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef BLOCK_H
+#define BLOCK_H
+
+#include "basics.h"
+#include "record.h"
+#include "reftable-blocksource.h"
+
+/*
+ * Writes reftable blocks. The block_writer is reused across blocks to minimize
+ * allocation overhead.
+ */
+struct block_writer {
+ uint8_t *buf;
+ uint32_t block_size;
+
+ /* Offset ofof the global header. Nonzero in the first block only. */
+ uint32_t header_off;
+
+ /* How often to restart keys. */
+ int restart_interval;
+ int hash_size;
+
+ /* Offset of next uint8_t to write. */
+ uint32_t next;
+ uint32_t *restarts;
+ uint32_t restart_len;
+ uint32_t restart_cap;
+
+ struct strbuf last_key;
+ int entries;
+};
+
+/*
+ * initializes the blockwriter to write `typ` entries, using `buf` as temporary
+ * storage. `buf` is not owned by the block_writer. */
+void block_writer_init(struct block_writer *bw, uint8_t typ, uint8_t *buf,
+ uint32_t block_size, uint32_t header_off, int hash_size);
+
+/* returns the block type (eg. 'r' for ref records. */
+uint8_t block_writer_type(struct block_writer *bw);
+
+/* appends the record, or -1 if it doesn't fit. */
+int block_writer_add(struct block_writer *w, struct reftable_record *rec);
+
+/* appends the key restarts, and compress the block if necessary. */
+int block_writer_finish(struct block_writer *w);
+
+/* clears out internally allocated block_writer members. */
+void block_writer_release(struct block_writer *bw);
+
+/* Read a block. */
+struct block_reader {
+ /* offset of the block header; nonzero for the first block in a
+ * reftable. */
+ uint32_t header_off;
+
+ /* the memory block */
+ struct reftable_block block;
+ int hash_size;
+
+ /* size of the data, excluding restart data. */
+ uint32_t block_len;
+ uint8_t *restart_bytes;
+ uint16_t restart_count;
+
+ /* size of the data in the file. For log blocks, this is the compressed
+ * size. */
+ uint32_t full_block_size;
+};
+
+/* Iterate over entries in a block */
+struct block_iter {
+ /* offset within the block of the next entry to read. */
+ uint32_t next_off;
+ struct block_reader *br;
+
+ /* key for last entry we read. */
+ struct strbuf last_key;
+};
+
+/* initializes a block reader. */
+int block_reader_init(struct block_reader *br, struct reftable_block *bl,
+ uint32_t header_off, uint32_t table_block_size,
+ int hash_size);
+
+/* Position `it` at start of the block */
+void block_reader_start(struct block_reader *br, struct block_iter *it);
+
+/* Position `it` to the `want` key in the block */
+int block_reader_seek(struct block_reader *br, struct block_iter *it,
+ struct strbuf *want);
+
+/* Returns the block type (eg. 'r' for refs) */
+uint8_t block_reader_type(struct block_reader *r);
+
+/* Decodes the first key in the block */
+int block_reader_first_key(struct block_reader *br, struct strbuf *key);
+
+void block_iter_copy_from(struct block_iter *dest, struct block_iter *src);
+
+/* return < 0 for error, 0 for OK, > 0 for EOF. */
+int block_iter_next(struct block_iter *it, struct reftable_record *rec);
+
+/* Seek to `want` with in the block pointed to by `it` */
+int block_iter_seek(struct block_iter *it, struct strbuf *want);
+
+/* deallocate memory for `it`. The block reader and its block is left intact. */
+void block_iter_close(struct block_iter *it);
+
+/* size of file header, depending on format version */
+int header_size(int version);
+
+/* size of file footer, depending on format version */
+int footer_size(int version);
+
+/* returns a block to its source. */
+void reftable_block_done(struct reftable_block *ret);
+
+#endif
diff --git a/reftable/block_test.c b/reftable/block_test.c
new file mode 100644
index 0000000..c3d35ee
--- /dev/null
+++ b/reftable/block_test.c
@@ -0,0 +1,121 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "block.h"
+
+#include "system.h"
+
+#include "blocksource.h"
+#include "basics.h"
+#include "constants.h"
+#include "record.h"
+#include "test_framework.h"
+#include "reftable-tests.h"
+
+static void test_block_read_write(void)
+{
+ const int header_off = 21; /* random */
+ char *names[30];
+ const int N = ARRAY_SIZE(names);
+ const int block_size = 1024;
+ struct reftable_block block = { NULL };
+ struct block_writer bw = {
+ .last_key = STRBUF_INIT,
+ };
+ struct reftable_ref_record ref = { NULL };
+ struct reftable_record rec = { NULL };
+ int i = 0;
+ int n;
+ struct block_reader br = { 0 };
+ struct block_iter it = { .last_key = STRBUF_INIT };
+ int j = 0;
+ struct strbuf want = STRBUF_INIT;
+
+ block.data = reftable_calloc(block_size);
+ block.len = block_size;
+ block.source = malloc_block_source();
+ block_writer_init(&bw, BLOCK_TYPE_REF, block.data, block_size,
+ header_off, hash_size(GIT_SHA1_FORMAT_ID));
+ reftable_record_from_ref(&rec, &ref);
+
+ for (i = 0; i < N; i++) {
+ char name[100];
+ uint8_t hash[GIT_SHA1_RAWSZ];
+ snprintf(name, sizeof(name), "branch%02d", i);
+ memset(hash, i, sizeof(hash));
+
+ ref.refname = name;
+ ref.value_type = REFTABLE_REF_VAL1;
+ ref.value.val1 = hash;
+
+ names[i] = xstrdup(name);
+ n = block_writer_add(&bw, &rec);
+ ref.refname = NULL;
+ ref.value_type = REFTABLE_REF_DELETION;
+ EXPECT(n == 0);
+ }
+
+ n = block_writer_finish(&bw);
+ EXPECT(n > 0);
+
+ block_writer_release(&bw);
+
+ block_reader_init(&br, &block, header_off, block_size, GIT_SHA1_RAWSZ);
+
+ block_reader_start(&br, &it);
+
+ while (1) {
+ int r = block_iter_next(&it, &rec);
+ EXPECT(r >= 0);
+ if (r > 0) {
+ break;
+ }
+ EXPECT_STREQ(names[j], ref.refname);
+ j++;
+ }
+
+ reftable_record_release(&rec);
+ block_iter_close(&it);
+
+ for (i = 0; i < N; i++) {
+ struct block_iter it = { .last_key = STRBUF_INIT };
+ strbuf_reset(&want);
+ strbuf_addstr(&want, names[i]);
+
+ n = block_reader_seek(&br, &it, &want);
+ EXPECT(n == 0);
+
+ n = block_iter_next(&it, &rec);
+ EXPECT(n == 0);
+
+ EXPECT_STREQ(names[i], ref.refname);
+
+ want.len--;
+ n = block_reader_seek(&br, &it, &want);
+ EXPECT(n == 0);
+
+ n = block_iter_next(&it, &rec);
+ EXPECT(n == 0);
+ EXPECT_STREQ(names[10 * (i / 10)], ref.refname);
+
+ block_iter_close(&it);
+ }
+
+ reftable_record_release(&rec);
+ reftable_block_done(&br.block);
+ strbuf_release(&want);
+ for (i = 0; i < N; i++) {
+ reftable_free(names[i]);
+ }
+}
+
+int block_test_main(int argc, const char *argv[])
+{
+ RUN_TEST(test_block_read_write);
+ return 0;
+}
diff --git a/reftable/blocksource.c b/reftable/blocksource.c
new file mode 100644
index 0000000..0044eec
--- /dev/null
+++ b/reftable/blocksource.c
@@ -0,0 +1,148 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "system.h"
+
+#include "basics.h"
+#include "blocksource.h"
+#include "reftable-blocksource.h"
+#include "reftable-error.h"
+
+static void strbuf_return_block(void *b, struct reftable_block *dest)
+{
+ memset(dest->data, 0xff, dest->len);
+ reftable_free(dest->data);
+}
+
+static void strbuf_close(void *b)
+{
+}
+
+static int strbuf_read_block(void *v, struct reftable_block *dest, uint64_t off,
+ uint32_t size)
+{
+ struct strbuf *b = v;
+ assert(off + size <= b->len);
+ dest->data = reftable_calloc(size);
+ memcpy(dest->data, b->buf + off, size);
+ dest->len = size;
+ return size;
+}
+
+static uint64_t strbuf_size(void *b)
+{
+ return ((struct strbuf *)b)->len;
+}
+
+static struct reftable_block_source_vtable strbuf_vtable = {
+ .size = &strbuf_size,
+ .read_block = &strbuf_read_block,
+ .return_block = &strbuf_return_block,
+ .close = &strbuf_close,
+};
+
+void block_source_from_strbuf(struct reftable_block_source *bs,
+ struct strbuf *buf)
+{
+ assert(!bs->ops);
+ bs->ops = &strbuf_vtable;
+ bs->arg = buf;
+}
+
+static void malloc_return_block(void *b, struct reftable_block *dest)
+{
+ memset(dest->data, 0xff, dest->len);
+ reftable_free(dest->data);
+}
+
+static struct reftable_block_source_vtable malloc_vtable = {
+ .return_block = &malloc_return_block,
+};
+
+static struct reftable_block_source malloc_block_source_instance = {
+ .ops = &malloc_vtable,
+};
+
+struct reftable_block_source malloc_block_source(void)
+{
+ return malloc_block_source_instance;
+}
+
+struct file_block_source {
+ int fd;
+ uint64_t size;
+};
+
+static uint64_t file_size(void *b)
+{
+ return ((struct file_block_source *)b)->size;
+}
+
+static void file_return_block(void *b, struct reftable_block *dest)
+{
+ memset(dest->data, 0xff, dest->len);
+ reftable_free(dest->data);
+}
+
+static void file_close(void *b)
+{
+ int fd = ((struct file_block_source *)b)->fd;
+ if (fd > 0) {
+ close(fd);
+ ((struct file_block_source *)b)->fd = 0;
+ }
+
+ reftable_free(b);
+}
+
+static int file_read_block(void *v, struct reftable_block *dest, uint64_t off,
+ uint32_t size)
+{
+ struct file_block_source *b = v;
+ assert(off + size <= b->size);
+ dest->data = reftable_malloc(size);
+ if (pread(b->fd, dest->data, size, off) != size)
+ return -1;
+ dest->len = size;
+ return size;
+}
+
+static struct reftable_block_source_vtable file_vtable = {
+ .size = &file_size,
+ .read_block = &file_read_block,
+ .return_block = &file_return_block,
+ .close = &file_close,
+};
+
+int reftable_block_source_from_file(struct reftable_block_source *bs,
+ const char *name)
+{
+ struct stat st = { 0 };
+ int err = 0;
+ int fd = open(name, O_RDONLY);
+ struct file_block_source *p = NULL;
+ if (fd < 0) {
+ if (errno == ENOENT) {
+ return REFTABLE_NOT_EXIST_ERROR;
+ }
+ return -1;
+ }
+
+ err = fstat(fd, &st);
+ if (err < 0)
+ return -1;
+
+ p = reftable_calloc(sizeof(struct file_block_source));
+ p->size = st.st_size;
+ p->fd = fd;
+
+ assert(!bs->ops);
+ bs->ops = &file_vtable;
+ bs->arg = p;
+ return 0;
+}
diff --git a/reftable/blocksource.h b/reftable/blocksource.h
new file mode 100644
index 0000000..072e272
--- /dev/null
+++ b/reftable/blocksource.h
@@ -0,0 +1,22 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef BLOCKSOURCE_H
+#define BLOCKSOURCE_H
+
+#include "system.h"
+
+struct reftable_block_source;
+
+/* Create an in-memory block source for reading reftables */
+void block_source_from_strbuf(struct reftable_block_source *bs,
+ struct strbuf *buf);
+
+struct reftable_block_source malloc_block_source(void);
+
+#endif
diff --git a/reftable/constants.h b/reftable/constants.h
new file mode 100644
index 0000000..5eee72c
--- /dev/null
+++ b/reftable/constants.h
@@ -0,0 +1,21 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef CONSTANTS_H
+#define CONSTANTS_H
+
+#define BLOCK_TYPE_LOG 'g'
+#define BLOCK_TYPE_INDEX 'i'
+#define BLOCK_TYPE_REF 'r'
+#define BLOCK_TYPE_OBJ 'o'
+#define BLOCK_TYPE_ANY 0
+
+#define MAX_RESTARTS ((1 << 16) - 1)
+#define DEFAULT_BLOCK_SIZE 4096
+
+#endif
diff --git a/reftable/dump.c b/reftable/dump.c
new file mode 100644
index 0000000..668cfa8
--- /dev/null
+++ b/reftable/dump.c
@@ -0,0 +1,105 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "reftable-blocksource.h"
+#include "reftable-error.h"
+#include "reftable-merged.h"
+#include "reftable-record.h"
+#include "reftable-tests.h"
+#include "reftable-writer.h"
+#include "reftable-iterator.h"
+#include "reftable-reader.h"
+#include "reftable-stack.h"
+#include "reftable-generic.h"
+#include "hash.h"
+
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+
+static int compact_stack(const char *stackdir)
+{
+ struct reftable_stack *stack = NULL;
+ struct reftable_write_options cfg = { 0 };
+
+ int err = reftable_new_stack(&stack, stackdir, cfg);
+ if (err < 0)
+ goto done;
+
+ err = reftable_stack_compact_all(stack, NULL);
+ if (err < 0)
+ goto done;
+done:
+ if (stack) {
+ reftable_stack_destroy(stack);
+ }
+ return err;
+}
+
+static void print_help(void)
+{
+ printf("usage: dump [-cst] arg\n\n"
+ "options: \n"
+ " -c compact\n"
+ " -t dump table\n"
+ " -s dump stack\n"
+ " -6 sha256 hash format\n"
+ " -h this help\n"
+ "\n");
+}
+
+int reftable_dump_main(int argc, char *const *argv)
+{
+ int err = 0;
+ int opt_dump_table = 0;
+ int opt_dump_stack = 0;
+ int opt_compact = 0;
+ uint32_t opt_hash_id = GIT_SHA1_FORMAT_ID;
+ const char *arg = NULL, *argv0 = argv[0];
+
+ for (; argc > 1; argv++, argc--)
+ if (*argv[1] != '-')
+ break;
+ else if (!strcmp("-t", argv[1]))
+ opt_dump_table = 1;
+ else if (!strcmp("-6", argv[1]))
+ opt_hash_id = GIT_SHA256_FORMAT_ID;
+ else if (!strcmp("-s", argv[1]))
+ opt_dump_stack = 1;
+ else if (!strcmp("-c", argv[1]))
+ opt_compact = 1;
+ else if (!strcmp("-?", argv[1]) || !strcmp("-h", argv[1])) {
+ print_help();
+ return 2;
+ }
+
+ if (argc != 2) {
+ fprintf(stderr, "need argument\n");
+ print_help();
+ return 2;
+ }
+
+ arg = argv[1];
+
+ if (opt_dump_table) {
+ err = reftable_reader_print_file(arg);
+ } else if (opt_dump_stack) {
+ err = reftable_stack_print_directory(arg, opt_hash_id);
+ } else if (opt_compact) {
+ err = compact_stack(arg);
+ }
+
+ if (err < 0) {
+ fprintf(stderr, "%s: %s: %s\n", argv0, arg,
+ reftable_error_str(err));
+ return 1;
+ }
+ return 0;
+}
diff --git a/reftable/error.c b/reftable/error.c
new file mode 100644
index 0000000..f6f16de
--- /dev/null
+++ b/reftable/error.c
@@ -0,0 +1,41 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "reftable-error.h"
+
+#include <stdio.h>
+
+const char *reftable_error_str(int err)
+{
+ static char buf[250];
+ switch (err) {
+ case REFTABLE_IO_ERROR:
+ return "I/O error";
+ case REFTABLE_FORMAT_ERROR:
+ return "corrupt reftable file";
+ case REFTABLE_NOT_EXIST_ERROR:
+ return "file does not exist";
+ case REFTABLE_LOCK_ERROR:
+ return "data is outdated";
+ case REFTABLE_API_ERROR:
+ return "misuse of the reftable API";
+ case REFTABLE_ZLIB_ERROR:
+ return "zlib failure";
+ case REFTABLE_NAME_CONFLICT:
+ return "file/directory conflict";
+ case REFTABLE_EMPTY_TABLE_ERROR:
+ return "wrote empty table";
+ case REFTABLE_REFNAME_ERROR:
+ return "invalid refname";
+ case -1:
+ return "general error";
+ default:
+ snprintf(buf, sizeof(buf), "unknown error code %d", err);
+ return buf;
+ }
+}
diff --git a/reftable/generic.c b/reftable/generic.c
new file mode 100644
index 0000000..7a8a738
--- /dev/null
+++ b/reftable/generic.c
@@ -0,0 +1,169 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "basics.h"
+#include "record.h"
+#include "generic.h"
+#include "reftable-iterator.h"
+#include "reftable-generic.h"
+
+int reftable_table_seek_ref(struct reftable_table *tab,
+ struct reftable_iterator *it, const char *name)
+{
+ struct reftable_ref_record ref = {
+ .refname = (char *)name,
+ };
+ struct reftable_record rec = { NULL };
+ reftable_record_from_ref(&rec, &ref);
+ return tab->ops->seek_record(tab->table_arg, it, &rec);
+}
+
+int reftable_table_seek_log(struct reftable_table *tab,
+ struct reftable_iterator *it, const char *name)
+{
+ struct reftable_log_record log = {
+ .refname = (char *)name,
+ .update_index = ~((uint64_t)0),
+ };
+ struct reftable_record rec = { NULL };
+ reftable_record_from_log(&rec, &log);
+ return tab->ops->seek_record(tab->table_arg, it, &rec);
+}
+
+int reftable_table_read_ref(struct reftable_table *tab, const char *name,
+ struct reftable_ref_record *ref)
+{
+ struct reftable_iterator it = { NULL };
+ int err = reftable_table_seek_ref(tab, &it, name);
+ if (err)
+ goto done;
+
+ err = reftable_iterator_next_ref(&it, ref);
+ if (err)
+ goto done;
+
+ if (strcmp(ref->refname, name) ||
+ reftable_ref_record_is_deletion(ref)) {
+ reftable_ref_record_release(ref);
+ err = 1;
+ goto done;
+ }
+
+done:
+ reftable_iterator_destroy(&it);
+ return err;
+}
+
+int reftable_table_print(struct reftable_table *tab) {
+ struct reftable_iterator it = { NULL };
+ struct reftable_ref_record ref = { NULL };
+ struct reftable_log_record log = { NULL };
+ uint32_t hash_id = reftable_table_hash_id(tab);
+ int err = reftable_table_seek_ref(tab, &it, "");
+ if (err < 0) {
+ return err;
+ }
+
+ while (1) {
+ err = reftable_iterator_next_ref(&it, &ref);
+ if (err > 0) {
+ break;
+ }
+ if (err < 0) {
+ return err;
+ }
+ reftable_ref_record_print(&ref, hash_id);
+ }
+ reftable_iterator_destroy(&it);
+ reftable_ref_record_release(&ref);
+
+ err = reftable_table_seek_log(tab, &it, "");
+ if (err < 0) {
+ return err;
+ }
+ while (1) {
+ err = reftable_iterator_next_log(&it, &log);
+ if (err > 0) {
+ break;
+ }
+ if (err < 0) {
+ return err;
+ }
+ reftable_log_record_print(&log, hash_id);
+ }
+ reftable_iterator_destroy(&it);
+ reftable_log_record_release(&log);
+ return 0;
+}
+
+uint64_t reftable_table_max_update_index(struct reftable_table *tab)
+{
+ return tab->ops->max_update_index(tab->table_arg);
+}
+
+uint64_t reftable_table_min_update_index(struct reftable_table *tab)
+{
+ return tab->ops->min_update_index(tab->table_arg);
+}
+
+uint32_t reftable_table_hash_id(struct reftable_table *tab)
+{
+ return tab->ops->hash_id(tab->table_arg);
+}
+
+void reftable_iterator_destroy(struct reftable_iterator *it)
+{
+ if (!it->ops) {
+ return;
+ }
+ it->ops->close(it->iter_arg);
+ it->ops = NULL;
+ FREE_AND_NULL(it->iter_arg);
+}
+
+int reftable_iterator_next_ref(struct reftable_iterator *it,
+ struct reftable_ref_record *ref)
+{
+ struct reftable_record rec = { NULL };
+ reftable_record_from_ref(&rec, ref);
+ return iterator_next(it, &rec);
+}
+
+int reftable_iterator_next_log(struct reftable_iterator *it,
+ struct reftable_log_record *log)
+{
+ struct reftable_record rec = { NULL };
+ reftable_record_from_log(&rec, log);
+ return iterator_next(it, &rec);
+}
+
+int iterator_next(struct reftable_iterator *it, struct reftable_record *rec)
+{
+ return it->ops->next(it->iter_arg, rec);
+}
+
+static int empty_iterator_next(void *arg, struct reftable_record *rec)
+{
+ return 1;
+}
+
+static void empty_iterator_close(void *arg)
+{
+}
+
+static struct reftable_iterator_vtable empty_vtable = {
+ .next = &empty_iterator_next,
+ .close = &empty_iterator_close,
+};
+
+void iterator_set_empty(struct reftable_iterator *it)
+{
+ assert(!it->ops);
+ it->iter_arg = NULL;
+ it->ops = &empty_vtable;
+}
diff --git a/reftable/generic.h b/reftable/generic.h
new file mode 100644
index 0000000..98886a0
--- /dev/null
+++ b/reftable/generic.h
@@ -0,0 +1,32 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef GENERIC_H
+#define GENERIC_H
+
+#include "record.h"
+#include "reftable-generic.h"
+
+/* generic interface to reftables */
+struct reftable_table_vtable {
+ int (*seek_record)(void *tab, struct reftable_iterator *it,
+ struct reftable_record *);
+ uint32_t (*hash_id)(void *tab);
+ uint64_t (*min_update_index)(void *tab);
+ uint64_t (*max_update_index)(void *tab);
+};
+
+struct reftable_iterator_vtable {
+ int (*next)(void *iter_arg, struct reftable_record *rec);
+ void (*close)(void *iter_arg);
+};
+
+void iterator_set_empty(struct reftable_iterator *it);
+int iterator_next(struct reftable_iterator *it, struct reftable_record *rec);
+
+#endif
diff --git a/reftable/iter.c b/reftable/iter.c
new file mode 100644
index 0000000..93d04f7
--- /dev/null
+++ b/reftable/iter.c
@@ -0,0 +1,194 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "iter.h"
+
+#include "system.h"
+
+#include "block.h"
+#include "generic.h"
+#include "constants.h"
+#include "reader.h"
+#include "reftable-error.h"
+
+int iterator_is_null(struct reftable_iterator *it)
+{
+ return !it->ops;
+}
+
+static void filtering_ref_iterator_close(void *iter_arg)
+{
+ struct filtering_ref_iterator *fri = iter_arg;
+ strbuf_release(&fri->oid);
+ reftable_iterator_destroy(&fri->it);
+}
+
+static int filtering_ref_iterator_next(void *iter_arg,
+ struct reftable_record *rec)
+{
+ struct filtering_ref_iterator *fri = iter_arg;
+ struct reftable_ref_record *ref = rec->data;
+ int err = 0;
+ while (1) {
+ err = reftable_iterator_next_ref(&fri->it, ref);
+ if (err != 0) {
+ break;
+ }
+
+ if (fri->double_check) {
+ struct reftable_iterator it = { NULL };
+
+ err = reftable_table_seek_ref(&fri->tab, &it,
+ ref->refname);
+ if (err == 0) {
+ err = reftable_iterator_next_ref(&it, ref);
+ }
+
+ reftable_iterator_destroy(&it);
+
+ if (err < 0) {
+ break;
+ }
+
+ if (err > 0) {
+ continue;
+ }
+ }
+
+ if (ref->value_type == REFTABLE_REF_VAL2 &&
+ (!memcmp(fri->oid.buf, ref->value.val2.target_value,
+ fri->oid.len) ||
+ !memcmp(fri->oid.buf, ref->value.val2.value,
+ fri->oid.len)))
+ return 0;
+
+ if (ref->value_type == REFTABLE_REF_VAL1 &&
+ !memcmp(fri->oid.buf, ref->value.val1, fri->oid.len)) {
+ return 0;
+ }
+ }
+
+ reftable_ref_record_release(ref);
+ return err;
+}
+
+static struct reftable_iterator_vtable filtering_ref_iterator_vtable = {
+ .next = &filtering_ref_iterator_next,
+ .close = &filtering_ref_iterator_close,
+};
+
+void iterator_from_filtering_ref_iterator(struct reftable_iterator *it,
+ struct filtering_ref_iterator *fri)
+{
+ assert(!it->ops);
+ it->iter_arg = fri;
+ it->ops = &filtering_ref_iterator_vtable;
+}
+
+static void indexed_table_ref_iter_close(void *p)
+{
+ struct indexed_table_ref_iter *it = p;
+ block_iter_close(&it->cur);
+ reftable_block_done(&it->block_reader.block);
+ reftable_free(it->offsets);
+ strbuf_release(&it->oid);
+}
+
+static int indexed_table_ref_iter_next_block(struct indexed_table_ref_iter *it)
+{
+ uint64_t off;
+ int err = 0;
+ if (it->offset_idx == it->offset_len) {
+ it->is_finished = 1;
+ return 1;
+ }
+
+ reftable_block_done(&it->block_reader.block);
+
+ off = it->offsets[it->offset_idx++];
+ err = reader_init_block_reader(it->r, &it->block_reader, off,
+ BLOCK_TYPE_REF);
+ if (err < 0) {
+ return err;
+ }
+ if (err > 0) {
+ /* indexed block does not exist. */
+ return REFTABLE_FORMAT_ERROR;
+ }
+ block_reader_start(&it->block_reader, &it->cur);
+ return 0;
+}
+
+static int indexed_table_ref_iter_next(void *p, struct reftable_record *rec)
+{
+ struct indexed_table_ref_iter *it = p;
+ struct reftable_ref_record *ref = rec->data;
+
+ while (1) {
+ int err = block_iter_next(&it->cur, rec);
+ if (err < 0) {
+ return err;
+ }
+
+ if (err > 0) {
+ err = indexed_table_ref_iter_next_block(it);
+ if (err < 0) {
+ return err;
+ }
+
+ if (it->is_finished) {
+ return 1;
+ }
+ continue;
+ }
+ /* BUG */
+ if (!memcmp(it->oid.buf, ref->value.val2.target_value,
+ it->oid.len) ||
+ !memcmp(it->oid.buf, ref->value.val2.value, it->oid.len)) {
+ return 0;
+ }
+ }
+}
+
+int new_indexed_table_ref_iter(struct indexed_table_ref_iter **dest,
+ struct reftable_reader *r, uint8_t *oid,
+ int oid_len, uint64_t *offsets, int offset_len)
+{
+ struct indexed_table_ref_iter empty = INDEXED_TABLE_REF_ITER_INIT;
+ struct indexed_table_ref_iter *itr =
+ reftable_calloc(sizeof(struct indexed_table_ref_iter));
+ int err = 0;
+
+ *itr = empty;
+ itr->r = r;
+ strbuf_add(&itr->oid, oid, oid_len);
+
+ itr->offsets = offsets;
+ itr->offset_len = offset_len;
+
+ err = indexed_table_ref_iter_next_block(itr);
+ if (err < 0) {
+ reftable_free(itr);
+ } else {
+ *dest = itr;
+ }
+ return err;
+}
+
+static struct reftable_iterator_vtable indexed_table_ref_iter_vtable = {
+ .next = &indexed_table_ref_iter_next,
+ .close = &indexed_table_ref_iter_close,
+};
+
+void iterator_from_indexed_table_ref_iter(struct reftable_iterator *it,
+ struct indexed_table_ref_iter *itr)
+{
+ assert(!it->ops);
+ it->iter_arg = itr;
+ it->ops = &indexed_table_ref_iter_vtable;
+}
diff --git a/reftable/iter.h b/reftable/iter.h
new file mode 100644
index 0000000..09eb0cb
--- /dev/null
+++ b/reftable/iter.h
@@ -0,0 +1,69 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef ITER_H
+#define ITER_H
+
+#include "system.h"
+#include "block.h"
+#include "record.h"
+
+#include "reftable-iterator.h"
+#include "reftable-generic.h"
+
+/* Returns true for a zeroed out iterator, such as the one returned from
+ * iterator_destroy. */
+int iterator_is_null(struct reftable_iterator *it);
+
+/* iterator that produces only ref records that point to `oid` */
+struct filtering_ref_iterator {
+ int double_check;
+ struct reftable_table tab;
+ struct strbuf oid;
+ struct reftable_iterator it;
+};
+#define FILTERING_REF_ITERATOR_INIT \
+ { \
+ .oid = STRBUF_INIT \
+ }
+
+void iterator_from_filtering_ref_iterator(struct reftable_iterator *,
+ struct filtering_ref_iterator *);
+
+/* iterator that produces only ref records that point to `oid`,
+ * but using the object index.
+ */
+struct indexed_table_ref_iter {
+ struct reftable_reader *r;
+ struct strbuf oid;
+
+ /* mutable */
+ uint64_t *offsets;
+
+ /* Points to the next offset to read. */
+ int offset_idx;
+ int offset_len;
+ struct block_reader block_reader;
+ struct block_iter cur;
+ int is_finished;
+};
+
+#define INDEXED_TABLE_REF_ITER_INIT \
+ { \
+ .cur = { .last_key = STRBUF_INIT }, .oid = STRBUF_INIT, \
+ }
+
+void iterator_from_indexed_table_ref_iter(struct reftable_iterator *it,
+ struct indexed_table_ref_iter *itr);
+
+/* Takes ownership of `offsets` */
+int new_indexed_table_ref_iter(struct indexed_table_ref_iter **dest,
+ struct reftable_reader *r, uint8_t *oid,
+ int oid_len, uint64_t *offsets, int offset_len);
+
+#endif
diff --git a/reftable/merged.c b/reftable/merged.c
new file mode 100644
index 0000000..e5b53da
--- /dev/null
+++ b/reftable/merged.c
@@ -0,0 +1,362 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "merged.h"
+
+#include "constants.h"
+#include "iter.h"
+#include "pq.h"
+#include "reader.h"
+#include "record.h"
+#include "generic.h"
+#include "reftable-merged.h"
+#include "reftable-error.h"
+#include "system.h"
+
+static int merged_iter_init(struct merged_iter *mi)
+{
+ int i = 0;
+ for (i = 0; i < mi->stack_len; i++) {
+ struct reftable_record rec = reftable_new_record(mi->typ);
+ int err = iterator_next(&mi->stack[i], &rec);
+ if (err < 0) {
+ return err;
+ }
+
+ if (err > 0) {
+ reftable_iterator_destroy(&mi->stack[i]);
+ reftable_record_destroy(&rec);
+ } else {
+ struct pq_entry e = {
+ .rec = rec,
+ .index = i,
+ };
+ merged_iter_pqueue_add(&mi->pq, e);
+ }
+ }
+
+ return 0;
+}
+
+static void merged_iter_close(void *p)
+{
+ struct merged_iter *mi = p;
+ int i = 0;
+ merged_iter_pqueue_release(&mi->pq);
+ for (i = 0; i < mi->stack_len; i++) {
+ reftable_iterator_destroy(&mi->stack[i]);
+ }
+ reftable_free(mi->stack);
+}
+
+static int merged_iter_advance_nonnull_subiter(struct merged_iter *mi,
+ size_t idx)
+{
+ struct reftable_record rec = reftable_new_record(mi->typ);
+ struct pq_entry e = {
+ .rec = rec,
+ .index = idx,
+ };
+ int err = iterator_next(&mi->stack[idx], &rec);
+ if (err < 0)
+ return err;
+
+ if (err > 0) {
+ reftable_iterator_destroy(&mi->stack[idx]);
+ reftable_record_destroy(&rec);
+ return 0;
+ }
+
+ merged_iter_pqueue_add(&mi->pq, e);
+ return 0;
+}
+
+static int merged_iter_advance_subiter(struct merged_iter *mi, size_t idx)
+{
+ if (iterator_is_null(&mi->stack[idx]))
+ return 0;
+ return merged_iter_advance_nonnull_subiter(mi, idx);
+}
+
+static int merged_iter_next_entry(struct merged_iter *mi,
+ struct reftable_record *rec)
+{
+ struct strbuf entry_key = STRBUF_INIT;
+ struct pq_entry entry = { 0 };
+ int err = 0;
+
+ if (merged_iter_pqueue_is_empty(mi->pq))
+ return 1;
+
+ entry = merged_iter_pqueue_remove(&mi->pq);
+ err = merged_iter_advance_subiter(mi, entry.index);
+ if (err < 0)
+ return err;
+
+ /*
+ One can also use reftable as datacenter-local storage, where the ref
+ database is maintained in globally consistent database (eg.
+ CockroachDB or Spanner). In this scenario, replication delays together
+ with compaction may cause newer tables to contain older entries. In
+ such a deployment, the loop below must be changed to collect all
+ entries for the same key, and return new the newest one.
+ */
+ reftable_record_key(&entry.rec, &entry_key);
+ while (!merged_iter_pqueue_is_empty(mi->pq)) {
+ struct pq_entry top = merged_iter_pqueue_top(mi->pq);
+ struct strbuf k = STRBUF_INIT;
+ int err = 0, cmp = 0;
+
+ reftable_record_key(&top.rec, &k);
+
+ cmp = strbuf_cmp(&k, &entry_key);
+ strbuf_release(&k);
+
+ if (cmp > 0) {
+ break;
+ }
+
+ merged_iter_pqueue_remove(&mi->pq);
+ err = merged_iter_advance_subiter(mi, top.index);
+ if (err < 0) {
+ return err;
+ }
+ reftable_record_destroy(&top.rec);
+ }
+
+ reftable_record_copy_from(rec, &entry.rec, hash_size(mi->hash_id));
+ reftable_record_destroy(&entry.rec);
+ strbuf_release(&entry_key);
+ return 0;
+}
+
+static int merged_iter_next(struct merged_iter *mi, struct reftable_record *rec)
+{
+ while (1) {
+ int err = merged_iter_next_entry(mi, rec);
+ if (err == 0 && mi->suppress_deletions &&
+ reftable_record_is_deletion(rec)) {
+ continue;
+ }
+
+ return err;
+ }
+}
+
+static int merged_iter_next_void(void *p, struct reftable_record *rec)
+{
+ struct merged_iter *mi = p;
+ if (merged_iter_pqueue_is_empty(mi->pq))
+ return 1;
+
+ return merged_iter_next(mi, rec);
+}
+
+static struct reftable_iterator_vtable merged_iter_vtable = {
+ .next = &merged_iter_next_void,
+ .close = &merged_iter_close,
+};
+
+static void iterator_from_merged_iter(struct reftable_iterator *it,
+ struct merged_iter *mi)
+{
+ assert(!it->ops);
+ it->iter_arg = mi;
+ it->ops = &merged_iter_vtable;
+}
+
+int reftable_new_merged_table(struct reftable_merged_table **dest,
+ struct reftable_table *stack, int n,
+ uint32_t hash_id)
+{
+ struct reftable_merged_table *m = NULL;
+ uint64_t last_max = 0;
+ uint64_t first_min = 0;
+ int i = 0;
+ for (i = 0; i < n; i++) {
+ uint64_t min = reftable_table_min_update_index(&stack[i]);
+ uint64_t max = reftable_table_max_update_index(&stack[i]);
+
+ if (reftable_table_hash_id(&stack[i]) != hash_id) {
+ return REFTABLE_FORMAT_ERROR;
+ }
+ if (i == 0 || min < first_min) {
+ first_min = min;
+ }
+ if (i == 0 || max > last_max) {
+ last_max = max;
+ }
+ }
+
+ m = reftable_calloc(sizeof(struct reftable_merged_table));
+ m->stack = stack;
+ m->stack_len = n;
+ m->min = first_min;
+ m->max = last_max;
+ m->hash_id = hash_id;
+ *dest = m;
+ return 0;
+}
+
+/* clears the list of subtable, without affecting the readers themselves. */
+void merged_table_release(struct reftable_merged_table *mt)
+{
+ FREE_AND_NULL(mt->stack);
+ mt->stack_len = 0;
+}
+
+void reftable_merged_table_free(struct reftable_merged_table *mt)
+{
+ if (!mt) {
+ return;
+ }
+ merged_table_release(mt);
+ reftable_free(mt);
+}
+
+uint64_t
+reftable_merged_table_max_update_index(struct reftable_merged_table *mt)
+{
+ return mt->max;
+}
+
+uint64_t
+reftable_merged_table_min_update_index(struct reftable_merged_table *mt)
+{
+ return mt->min;
+}
+
+static int reftable_table_seek_record(struct reftable_table *tab,
+ struct reftable_iterator *it,
+ struct reftable_record *rec)
+{
+ return tab->ops->seek_record(tab->table_arg, it, rec);
+}
+
+static int merged_table_seek_record(struct reftable_merged_table *mt,
+ struct reftable_iterator *it,
+ struct reftable_record *rec)
+{
+ struct reftable_iterator *iters = reftable_calloc(
+ sizeof(struct reftable_iterator) * mt->stack_len);
+ struct merged_iter merged = {
+ .stack = iters,
+ .typ = reftable_record_type(rec),
+ .hash_id = mt->hash_id,
+ .suppress_deletions = mt->suppress_deletions,
+ };
+ int n = 0;
+ int err = 0;
+ int i = 0;
+ for (i = 0; i < mt->stack_len && err == 0; i++) {
+ int e = reftable_table_seek_record(&mt->stack[i], &iters[n],
+ rec);
+ if (e < 0) {
+ err = e;
+ }
+ if (e == 0) {
+ n++;
+ }
+ }
+ if (err < 0) {
+ int i = 0;
+ for (i = 0; i < n; i++) {
+ reftable_iterator_destroy(&iters[i]);
+ }
+ reftable_free(iters);
+ return err;
+ }
+
+ merged.stack_len = n;
+ err = merged_iter_init(&merged);
+ if (err < 0) {
+ merged_iter_close(&merged);
+ return err;
+ } else {
+ struct merged_iter *p =
+ reftable_malloc(sizeof(struct merged_iter));
+ *p = merged;
+ iterator_from_merged_iter(it, p);
+ }
+ return 0;
+}
+
+int reftable_merged_table_seek_ref(struct reftable_merged_table *mt,
+ struct reftable_iterator *it,
+ const char *name)
+{
+ struct reftable_ref_record ref = {
+ .refname = (char *)name,
+ };
+ struct reftable_record rec = { NULL };
+ reftable_record_from_ref(&rec, &ref);
+ return merged_table_seek_record(mt, it, &rec);
+}
+
+int reftable_merged_table_seek_log_at(struct reftable_merged_table *mt,
+ struct reftable_iterator *it,
+ const char *name, uint64_t update_index)
+{
+ struct reftable_log_record log = {
+ .refname = (char *)name,
+ .update_index = update_index,
+ };
+ struct reftable_record rec = { NULL };
+ reftable_record_from_log(&rec, &log);
+ return merged_table_seek_record(mt, it, &rec);
+}
+
+int reftable_merged_table_seek_log(struct reftable_merged_table *mt,
+ struct reftable_iterator *it,
+ const char *name)
+{
+ uint64_t max = ~((uint64_t)0);
+ return reftable_merged_table_seek_log_at(mt, it, name, max);
+}
+
+uint32_t reftable_merged_table_hash_id(struct reftable_merged_table *mt)
+{
+ return mt->hash_id;
+}
+
+static int reftable_merged_table_seek_void(void *tab,
+ struct reftable_iterator *it,
+ struct reftable_record *rec)
+{
+ return merged_table_seek_record(tab, it, rec);
+}
+
+static uint32_t reftable_merged_table_hash_id_void(void *tab)
+{
+ return reftable_merged_table_hash_id(tab);
+}
+
+static uint64_t reftable_merged_table_min_update_index_void(void *tab)
+{
+ return reftable_merged_table_min_update_index(tab);
+}
+
+static uint64_t reftable_merged_table_max_update_index_void(void *tab)
+{
+ return reftable_merged_table_max_update_index(tab);
+}
+
+static struct reftable_table_vtable merged_table_vtable = {
+ .seek_record = reftable_merged_table_seek_void,
+ .hash_id = reftable_merged_table_hash_id_void,
+ .min_update_index = reftable_merged_table_min_update_index_void,
+ .max_update_index = reftable_merged_table_max_update_index_void,
+};
+
+void reftable_table_from_merged_table(struct reftable_table *tab,
+ struct reftable_merged_table *merged)
+{
+ assert(!tab->ops);
+ tab->ops = &merged_table_vtable;
+ tab->table_arg = merged;
+}
diff --git a/reftable/merged.h b/reftable/merged.h
new file mode 100644
index 0000000..8c4d4d5
--- /dev/null
+++ b/reftable/merged.h
@@ -0,0 +1,35 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef MERGED_H
+#define MERGED_H
+
+#include "pq.h"
+
+struct reftable_merged_table {
+ struct reftable_table *stack;
+ size_t stack_len;
+ uint32_t hash_id;
+ int suppress_deletions;
+
+ uint64_t min;
+ uint64_t max;
+};
+
+struct merged_iter {
+ struct reftable_iterator *stack;
+ uint32_t hash_id;
+ size_t stack_len;
+ uint8_t typ;
+ int suppress_deletions;
+ struct merged_iter_pqueue pq;
+};
+
+void merged_table_release(struct reftable_merged_table *mt);
+
+#endif
diff --git a/reftable/merged_test.c b/reftable/merged_test.c
new file mode 100644
index 0000000..1e2afe3
--- /dev/null
+++ b/reftable/merged_test.c
@@ -0,0 +1,292 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "merged.h"
+
+#include "system.h"
+
+#include "basics.h"
+#include "blocksource.h"
+#include "constants.h"
+#include "reader.h"
+#include "record.h"
+#include "test_framework.h"
+#include "reftable-merged.h"
+#include "reftable-tests.h"
+#include "reftable-generic.h"
+#include "reftable-writer.h"
+
+static void write_test_table(struct strbuf *buf,
+ struct reftable_ref_record refs[], int n)
+{
+ int min = 0xffffffff;
+ int max = 0;
+ int i = 0;
+ int err;
+
+ struct reftable_write_options opts = {
+ .block_size = 256,
+ };
+ struct reftable_writer *w = NULL;
+ for (i = 0; i < n; i++) {
+ uint64_t ui = refs[i].update_index;
+ if (ui > max) {
+ max = ui;
+ }
+ if (ui < min) {
+ min = ui;
+ }
+ }
+
+ w = reftable_new_writer(&strbuf_add_void, buf, &opts);
+ reftable_writer_set_limits(w, min, max);
+
+ for (i = 0; i < n; i++) {
+ uint64_t before = refs[i].update_index;
+ int n = reftable_writer_add_ref(w, &refs[i]);
+ assert(n == 0);
+ assert(before == refs[i].update_index);
+ }
+
+ err = reftable_writer_close(w);
+ EXPECT_ERR(err);
+
+ reftable_writer_free(w);
+}
+
+static struct reftable_merged_table *
+merged_table_from_records(struct reftable_ref_record **refs,
+ struct reftable_block_source **source,
+ struct reftable_reader ***readers, int *sizes,
+ struct strbuf *buf, int n)
+{
+ int i = 0;
+ struct reftable_merged_table *mt = NULL;
+ int err;
+ struct reftable_table *tabs =
+ reftable_calloc(n * sizeof(struct reftable_table));
+ *readers = reftable_calloc(n * sizeof(struct reftable_reader *));
+ *source = reftable_calloc(n * sizeof(**source));
+ for (i = 0; i < n; i++) {
+ write_test_table(&buf[i], refs[i], sizes[i]);
+ block_source_from_strbuf(&(*source)[i], &buf[i]);
+
+ err = reftable_new_reader(&(*readers)[i], &(*source)[i],
+ "name");
+ EXPECT_ERR(err);
+ reftable_table_from_reader(&tabs[i], (*readers)[i]);
+ }
+
+ err = reftable_new_merged_table(&mt, tabs, n, GIT_SHA1_FORMAT_ID);
+ EXPECT_ERR(err);
+ return mt;
+}
+
+static void readers_destroy(struct reftable_reader **readers, size_t n)
+{
+ int i = 0;
+ for (; i < n; i++)
+ reftable_reader_free(readers[i]);
+ reftable_free(readers);
+}
+
+static void test_merged_between(void)
+{
+ uint8_t hash1[GIT_SHA1_RAWSZ] = { 1, 2, 3, 0 };
+
+ struct reftable_ref_record r1[] = { {
+ .refname = "b",
+ .update_index = 1,
+ .value_type = REFTABLE_REF_VAL1,
+ .value.val1 = hash1,
+ } };
+ struct reftable_ref_record r2[] = { {
+ .refname = "a",
+ .update_index = 2,
+ .value_type = REFTABLE_REF_DELETION,
+ } };
+
+ struct reftable_ref_record *refs[] = { r1, r2 };
+ int sizes[] = { 1, 1 };
+ struct strbuf bufs[2] = { STRBUF_INIT, STRBUF_INIT };
+ struct reftable_block_source *bs = NULL;
+ struct reftable_reader **readers = NULL;
+ struct reftable_merged_table *mt =
+ merged_table_from_records(refs, &bs, &readers, sizes, bufs, 2);
+ int i;
+ struct reftable_ref_record ref = { NULL };
+ struct reftable_iterator it = { NULL };
+ int err = reftable_merged_table_seek_ref(mt, &it, "a");
+ EXPECT_ERR(err);
+
+ err = reftable_iterator_next_ref(&it, &ref);
+ EXPECT_ERR(err);
+ EXPECT(ref.update_index == 2);
+ reftable_ref_record_release(&ref);
+ reftable_iterator_destroy(&it);
+ readers_destroy(readers, 2);
+ reftable_merged_table_free(mt);
+ for (i = 0; i < ARRAY_SIZE(bufs); i++) {
+ strbuf_release(&bufs[i]);
+ }
+ reftable_free(bs);
+}
+
+static void test_merged(void)
+{
+ uint8_t hash1[GIT_SHA1_RAWSZ] = { 1 };
+ uint8_t hash2[GIT_SHA1_RAWSZ] = { 2 };
+ struct reftable_ref_record r1[] = {
+ {
+ .refname = "a",
+ .update_index = 1,
+ .value_type = REFTABLE_REF_VAL1,
+ .value.val1 = hash1,
+ },
+ {
+ .refname = "b",
+ .update_index = 1,
+ .value_type = REFTABLE_REF_VAL1,
+ .value.val1 = hash1,
+ },
+ {
+ .refname = "c",
+ .update_index = 1,
+ .value_type = REFTABLE_REF_VAL1,
+ .value.val1 = hash1,
+ }
+ };
+ struct reftable_ref_record r2[] = { {
+ .refname = "a",
+ .update_index = 2,
+ .value_type = REFTABLE_REF_DELETION,
+ } };
+ struct reftable_ref_record r3[] = {
+ {
+ .refname = "c",
+ .update_index = 3,
+ .value_type = REFTABLE_REF_VAL1,
+ .value.val1 = hash2,
+ },
+ {
+ .refname = "d",
+ .update_index = 3,
+ .value_type = REFTABLE_REF_VAL1,
+ .value.val1 = hash1,
+ },
+ };
+
+ struct reftable_ref_record want[] = {
+ r2[0],
+ r1[1],
+ r3[0],
+ r3[1],
+ };
+
+ struct reftable_ref_record *refs[] = { r1, r2, r3 };
+ int sizes[3] = { 3, 1, 2 };
+ struct strbuf bufs[3] = { STRBUF_INIT, STRBUF_INIT, STRBUF_INIT };
+ struct reftable_block_source *bs = NULL;
+ struct reftable_reader **readers = NULL;
+ struct reftable_merged_table *mt =
+ merged_table_from_records(refs, &bs, &readers, sizes, bufs, 3);
+
+ struct reftable_iterator it = { NULL };
+ int err = reftable_merged_table_seek_ref(mt, &it, "a");
+ struct reftable_ref_record *out = NULL;
+ size_t len = 0;
+ size_t cap = 0;
+ int i = 0;
+
+ EXPECT_ERR(err);
+ while (len < 100) { /* cap loops/recursion. */
+ struct reftable_ref_record ref = { NULL };
+ int err = reftable_iterator_next_ref(&it, &ref);
+ if (err > 0) {
+ break;
+ }
+ if (len == cap) {
+ cap = 2 * cap + 1;
+ out = reftable_realloc(
+ out, sizeof(struct reftable_ref_record) * cap);
+ }
+ out[len++] = ref;
+ }
+ reftable_iterator_destroy(&it);
+
+ assert(ARRAY_SIZE(want) == len);
+ for (i = 0; i < len; i++) {
+ assert(reftable_ref_record_equal(&want[i], &out[i],
+ GIT_SHA1_RAWSZ));
+ }
+ for (i = 0; i < len; i++) {
+ reftable_ref_record_release(&out[i]);
+ }
+ reftable_free(out);
+
+ for (i = 0; i < 3; i++) {
+ strbuf_release(&bufs[i]);
+ }
+ readers_destroy(readers, 3);
+ reftable_merged_table_free(mt);
+ reftable_free(bs);
+}
+
+static void test_default_write_opts(void)
+{
+ struct reftable_write_options opts = { 0 };
+ struct strbuf buf = STRBUF_INIT;
+ struct reftable_writer *w =
+ reftable_new_writer(&strbuf_add_void, &buf, &opts);
+
+ struct reftable_ref_record rec = {
+ .refname = "master",
+ .update_index = 1,
+ };
+ int err;
+ struct reftable_block_source source = { NULL };
+ struct reftable_table *tab = reftable_calloc(sizeof(*tab) * 1);
+ uint32_t hash_id;
+ struct reftable_reader *rd = NULL;
+ struct reftable_merged_table *merged = NULL;
+
+ reftable_writer_set_limits(w, 1, 1);
+
+ err = reftable_writer_add_ref(w, &rec);
+ EXPECT_ERR(err);
+
+ err = reftable_writer_close(w);
+ EXPECT_ERR(err);
+ reftable_writer_free(w);
+
+ block_source_from_strbuf(&source, &buf);
+
+ err = reftable_new_reader(&rd, &source, "filename");
+ EXPECT_ERR(err);
+
+ hash_id = reftable_reader_hash_id(rd);
+ assert(hash_id == GIT_SHA1_FORMAT_ID);
+
+ reftable_table_from_reader(&tab[0], rd);
+ err = reftable_new_merged_table(&merged, tab, 1, GIT_SHA1_FORMAT_ID);
+ EXPECT_ERR(err);
+
+ reftable_reader_free(rd);
+ reftable_merged_table_free(merged);
+ strbuf_release(&buf);
+}
+
+/* XXX test refs_for(oid) */
+
+int merged_test_main(int argc, const char *argv[])
+{
+ RUN_TEST(test_merged_between);
+ RUN_TEST(test_merged);
+ RUN_TEST(test_default_write_opts);
+ return 0;
+}
diff --git a/reftable/pq.c b/reftable/pq.c
new file mode 100644
index 0000000..8918d15
--- /dev/null
+++ b/reftable/pq.c
@@ -0,0 +1,115 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "pq.h"
+
+#include "reftable-record.h"
+#include "system.h"
+#include "basics.h"
+
+static int pq_less(struct pq_entry a, struct pq_entry b)
+{
+ struct strbuf ak = STRBUF_INIT;
+ struct strbuf bk = STRBUF_INIT;
+ int cmp = 0;
+ reftable_record_key(&a.rec, &ak);
+ reftable_record_key(&b.rec, &bk);
+
+ cmp = strbuf_cmp(&ak, &bk);
+
+ strbuf_release(&ak);
+ strbuf_release(&bk);
+
+ if (cmp == 0)
+ return a.index > b.index;
+
+ return cmp < 0;
+}
+
+struct pq_entry merged_iter_pqueue_top(struct merged_iter_pqueue pq)
+{
+ return pq.heap[0];
+}
+
+int merged_iter_pqueue_is_empty(struct merged_iter_pqueue pq)
+{
+ return pq.len == 0;
+}
+
+void merged_iter_pqueue_check(struct merged_iter_pqueue pq)
+{
+ int i = 0;
+ for (i = 1; i < pq.len; i++) {
+ int parent = (i - 1) / 2;
+
+ assert(pq_less(pq.heap[parent], pq.heap[i]));
+ }
+}
+
+struct pq_entry merged_iter_pqueue_remove(struct merged_iter_pqueue *pq)
+{
+ int i = 0;
+ struct pq_entry e = pq->heap[0];
+ pq->heap[0] = pq->heap[pq->len - 1];
+ pq->len--;
+
+ i = 0;
+ while (i < pq->len) {
+ int min = i;
+ int j = 2 * i + 1;
+ int k = 2 * i + 2;
+ if (j < pq->len && pq_less(pq->heap[j], pq->heap[i])) {
+ min = j;
+ }
+ if (k < pq->len && pq_less(pq->heap[k], pq->heap[min])) {
+ min = k;
+ }
+
+ if (min == i) {
+ break;
+ }
+
+ SWAP(pq->heap[i], pq->heap[min]);
+ i = min;
+ }
+
+ return e;
+}
+
+void merged_iter_pqueue_add(struct merged_iter_pqueue *pq, struct pq_entry e)
+{
+ int i = 0;
+ if (pq->len == pq->cap) {
+ pq->cap = 2 * pq->cap + 1;
+ pq->heap = reftable_realloc(pq->heap,
+ pq->cap * sizeof(struct pq_entry));
+ }
+
+ pq->heap[pq->len++] = e;
+ i = pq->len - 1;
+ while (i > 0) {
+ int j = (i - 1) / 2;
+ if (pq_less(pq->heap[j], pq->heap[i])) {
+ break;
+ }
+
+ SWAP(pq->heap[j], pq->heap[i]);
+
+ i = j;
+ }
+}
+
+void merged_iter_pqueue_release(struct merged_iter_pqueue *pq)
+{
+ int i = 0;
+ for (i = 0; i < pq->len; i++) {
+ reftable_record_destroy(&pq->heap[i].rec);
+ }
+ FREE_AND_NULL(pq->heap);
+ pq->len = pq->cap = 0;
+}
diff --git a/reftable/pq.h b/reftable/pq.h
new file mode 100644
index 0000000..385d2fb
--- /dev/null
+++ b/reftable/pq.h
@@ -0,0 +1,32 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef PQ_H
+#define PQ_H
+
+#include "record.h"
+
+struct pq_entry {
+ int index;
+ struct reftable_record rec;
+};
+
+struct merged_iter_pqueue {
+ struct pq_entry *heap;
+ size_t len;
+ size_t cap;
+};
+
+struct pq_entry merged_iter_pqueue_top(struct merged_iter_pqueue pq);
+int merged_iter_pqueue_is_empty(struct merged_iter_pqueue pq);
+void merged_iter_pqueue_check(struct merged_iter_pqueue pq);
+struct pq_entry merged_iter_pqueue_remove(struct merged_iter_pqueue *pq);
+void merged_iter_pqueue_add(struct merged_iter_pqueue *pq, struct pq_entry e);
+void merged_iter_pqueue_release(struct merged_iter_pqueue *pq);
+
+#endif
diff --git a/reftable/pq_test.c b/reftable/pq_test.c
new file mode 100644
index 0000000..ad21673
--- /dev/null
+++ b/reftable/pq_test.c
@@ -0,0 +1,72 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "system.h"
+
+#include "basics.h"
+#include "constants.h"
+#include "pq.h"
+#include "record.h"
+#include "reftable-tests.h"
+#include "test_framework.h"
+
+static void test_pq(void)
+{
+ char *names[54] = { NULL };
+ int N = ARRAY_SIZE(names) - 1;
+
+ struct merged_iter_pqueue pq = { NULL };
+ const char *last = NULL;
+
+ int i = 0;
+ for (i = 0; i < N; i++) {
+ char name[100];
+ snprintf(name, sizeof(name), "%02d", i);
+ names[i] = xstrdup(name);
+ }
+
+ i = 1;
+ do {
+ struct reftable_record rec =
+ reftable_new_record(BLOCK_TYPE_REF);
+ struct pq_entry e = { 0 };
+
+ reftable_record_as_ref(&rec)->refname = names[i];
+ e.rec = rec;
+ merged_iter_pqueue_add(&pq, e);
+ merged_iter_pqueue_check(pq);
+ i = (i * 7) % N;
+ } while (i != 1);
+
+ while (!merged_iter_pqueue_is_empty(pq)) {
+ struct pq_entry e = merged_iter_pqueue_remove(&pq);
+ struct reftable_ref_record *ref =
+ reftable_record_as_ref(&e.rec);
+
+ merged_iter_pqueue_check(pq);
+
+ if (last) {
+ assert(strcmp(last, ref->refname) < 0);
+ }
+ last = ref->refname;
+ ref->refname = NULL;
+ reftable_free(ref);
+ }
+
+ for (i = 0; i < N; i++) {
+ reftable_free(names[i]);
+ }
+
+ merged_iter_pqueue_release(&pq);
+}
+
+int pq_test_main(int argc, const char *argv[])
+{
+ RUN_TEST(test_pq);
+ return 0;
+}
diff --git a/reftable/publicbasics.c b/reftable/publicbasics.c
new file mode 100644
index 0000000..bd0a02d
--- /dev/null
+++ b/reftable/publicbasics.c
@@ -0,0 +1,58 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "reftable-malloc.h"
+
+#include "basics.h"
+#include "system.h"
+
+static void *(*reftable_malloc_ptr)(size_t sz) = &malloc;
+static void *(*reftable_realloc_ptr)(void *, size_t) = &realloc;
+static void (*reftable_free_ptr)(void *) = &free;
+
+void *reftable_malloc(size_t sz)
+{
+ return (*reftable_malloc_ptr)(sz);
+}
+
+void *reftable_realloc(void *p, size_t sz)
+{
+ return (*reftable_realloc_ptr)(p, sz);
+}
+
+void reftable_free(void *p)
+{
+ reftable_free_ptr(p);
+}
+
+void *reftable_calloc(size_t sz)
+{
+ void *p = reftable_malloc(sz);
+ memset(p, 0, sz);
+ return p;
+}
+
+void reftable_set_alloc(void *(*malloc)(size_t),
+ void *(*realloc)(void *, size_t), void (*free)(void *))
+{
+ reftable_malloc_ptr = malloc;
+ reftable_realloc_ptr = realloc;
+ reftable_free_ptr = free;
+}
+
+int hash_size(uint32_t id)
+{
+ switch (id) {
+ case 0:
+ case GIT_SHA1_FORMAT_ID:
+ return GIT_SHA1_RAWSZ;
+ case GIT_SHA256_FORMAT_ID:
+ return GIT_SHA256_RAWSZ;
+ }
+ abort();
+}
diff --git a/reftable/reader.c b/reftable/reader.c
new file mode 100644
index 0000000..49f4ec0
--- /dev/null
+++ b/reftable/reader.c
@@ -0,0 +1,801 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "reader.h"
+
+#include "system.h"
+#include "block.h"
+#include "constants.h"
+#include "generic.h"
+#include "iter.h"
+#include "record.h"
+#include "reftable-error.h"
+#include "reftable-generic.h"
+#include "tree.h"
+
+uint64_t block_source_size(struct reftable_block_source *source)
+{
+ return source->ops->size(source->arg);
+}
+
+int block_source_read_block(struct reftable_block_source *source,
+ struct reftable_block *dest, uint64_t off,
+ uint32_t size)
+{
+ int result = source->ops->read_block(source->arg, dest, off, size);
+ dest->source = *source;
+ return result;
+}
+
+void block_source_close(struct reftable_block_source *source)
+{
+ if (!source->ops) {
+ return;
+ }
+
+ source->ops->close(source->arg);
+ source->ops = NULL;
+}
+
+static struct reftable_reader_offsets *
+reader_offsets_for(struct reftable_reader *r, uint8_t typ)
+{
+ switch (typ) {
+ case BLOCK_TYPE_REF:
+ return &r->ref_offsets;
+ case BLOCK_TYPE_LOG:
+ return &r->log_offsets;
+ case BLOCK_TYPE_OBJ:
+ return &r->obj_offsets;
+ }
+ abort();
+}
+
+static int reader_get_block(struct reftable_reader *r,
+ struct reftable_block *dest, uint64_t off,
+ uint32_t sz)
+{
+ if (off >= r->size)
+ return 0;
+
+ if (off + sz > r->size) {
+ sz = r->size - off;
+ }
+
+ return block_source_read_block(&r->source, dest, off, sz);
+}
+
+uint32_t reftable_reader_hash_id(struct reftable_reader *r)
+{
+ return r->hash_id;
+}
+
+const char *reader_name(struct reftable_reader *r)
+{
+ return r->name;
+}
+
+static int parse_footer(struct reftable_reader *r, uint8_t *footer,
+ uint8_t *header)
+{
+ uint8_t *f = footer;
+ uint8_t first_block_typ;
+ int err = 0;
+ uint32_t computed_crc;
+ uint32_t file_crc;
+
+ if (memcmp(f, "REFT", 4)) {
+ err = REFTABLE_FORMAT_ERROR;
+ goto done;
+ }
+ f += 4;
+
+ if (memcmp(footer, header, header_size(r->version))) {
+ err = REFTABLE_FORMAT_ERROR;
+ goto done;
+ }
+
+ f++;
+ r->block_size = get_be24(f);
+
+ f += 3;
+ r->min_update_index = get_be64(f);
+ f += 8;
+ r->max_update_index = get_be64(f);
+ f += 8;
+
+ if (r->version == 1) {
+ r->hash_id = GIT_SHA1_FORMAT_ID;
+ } else {
+ r->hash_id = get_be32(f);
+ switch (r->hash_id) {
+ case GIT_SHA1_FORMAT_ID:
+ break;
+ case GIT_SHA256_FORMAT_ID:
+ break;
+ default:
+ err = REFTABLE_FORMAT_ERROR;
+ goto done;
+ }
+ f += 4;
+ }
+
+ r->ref_offsets.index_offset = get_be64(f);
+ f += 8;
+
+ r->obj_offsets.offset = get_be64(f);
+ f += 8;
+
+ r->object_id_len = r->obj_offsets.offset & ((1 << 5) - 1);
+ r->obj_offsets.offset >>= 5;
+
+ r->obj_offsets.index_offset = get_be64(f);
+ f += 8;
+ r->log_offsets.offset = get_be64(f);
+ f += 8;
+ r->log_offsets.index_offset = get_be64(f);
+ f += 8;
+
+ computed_crc = crc32(0, footer, f - footer);
+ file_crc = get_be32(f);
+ f += 4;
+ if (computed_crc != file_crc) {
+ err = REFTABLE_FORMAT_ERROR;
+ goto done;
+ }
+
+ first_block_typ = header[header_size(r->version)];
+ r->ref_offsets.is_present = (first_block_typ == BLOCK_TYPE_REF);
+ r->ref_offsets.offset = 0;
+ r->log_offsets.is_present = (first_block_typ == BLOCK_TYPE_LOG ||
+ r->log_offsets.offset > 0);
+ r->obj_offsets.is_present = r->obj_offsets.offset > 0;
+ err = 0;
+done:
+ return err;
+}
+
+int init_reader(struct reftable_reader *r, struct reftable_block_source *source,
+ const char *name)
+{
+ struct reftable_block footer = { NULL };
+ struct reftable_block header = { NULL };
+ int err = 0;
+ uint64_t file_size = block_source_size(source);
+
+ /* Need +1 to read type of first block. */
+ uint32_t read_size = header_size(2) + 1; /* read v2 because it's larger. */
+ memset(r, 0, sizeof(struct reftable_reader));
+
+ if (read_size > file_size) {
+ err = REFTABLE_FORMAT_ERROR;
+ goto done;
+ }
+
+ err = block_source_read_block(source, &header, 0, read_size);
+ if (err != header_size(2) + 1) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+
+ if (memcmp(header.data, "REFT", 4)) {
+ err = REFTABLE_FORMAT_ERROR;
+ goto done;
+ }
+ r->version = header.data[4];
+ if (r->version != 1 && r->version != 2) {
+ err = REFTABLE_FORMAT_ERROR;
+ goto done;
+ }
+
+ r->size = file_size - footer_size(r->version);
+ r->source = *source;
+ r->name = xstrdup(name);
+ r->hash_id = 0;
+
+ err = block_source_read_block(source, &footer, r->size,
+ footer_size(r->version));
+ if (err != footer_size(r->version)) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+
+ err = parse_footer(r, footer.data, header.data);
+done:
+ reftable_block_done(&footer);
+ reftable_block_done(&header);
+ return err;
+}
+
+struct table_iter {
+ struct reftable_reader *r;
+ uint8_t typ;
+ uint64_t block_off;
+ struct block_iter bi;
+ int is_finished;
+};
+#define TABLE_ITER_INIT \
+ { \
+ .bi = {.last_key = STRBUF_INIT } \
+ }
+
+static void table_iter_copy_from(struct table_iter *dest,
+ struct table_iter *src)
+{
+ dest->r = src->r;
+ dest->typ = src->typ;
+ dest->block_off = src->block_off;
+ dest->is_finished = src->is_finished;
+ block_iter_copy_from(&dest->bi, &src->bi);
+}
+
+static int table_iter_next_in_block(struct table_iter *ti,
+ struct reftable_record *rec)
+{
+ int res = block_iter_next(&ti->bi, rec);
+ if (res == 0 && reftable_record_type(rec) == BLOCK_TYPE_REF) {
+ ((struct reftable_ref_record *)rec->data)->update_index +=
+ ti->r->min_update_index;
+ }
+
+ return res;
+}
+
+static void table_iter_block_done(struct table_iter *ti)
+{
+ if (!ti->bi.br) {
+ return;
+ }
+ reftable_block_done(&ti->bi.br->block);
+ FREE_AND_NULL(ti->bi.br);
+
+ ti->bi.last_key.len = 0;
+ ti->bi.next_off = 0;
+}
+
+static int32_t extract_block_size(uint8_t *data, uint8_t *typ, uint64_t off,
+ int version)
+{
+ int32_t result = 0;
+
+ if (off == 0) {
+ data += header_size(version);
+ }
+
+ *typ = data[0];
+ if (reftable_is_block_type(*typ)) {
+ result = get_be24(data + 1);
+ }
+ return result;
+}
+
+int reader_init_block_reader(struct reftable_reader *r, struct block_reader *br,
+ uint64_t next_off, uint8_t want_typ)
+{
+ int32_t guess_block_size = r->block_size ? r->block_size :
+ DEFAULT_BLOCK_SIZE;
+ struct reftable_block block = { NULL };
+ uint8_t block_typ = 0;
+ int err = 0;
+ uint32_t header_off = next_off ? 0 : header_size(r->version);
+ int32_t block_size = 0;
+
+ if (next_off >= r->size)
+ return 1;
+
+ err = reader_get_block(r, &block, next_off, guess_block_size);
+ if (err < 0)
+ return err;
+
+ block_size = extract_block_size(block.data, &block_typ, next_off,
+ r->version);
+ if (block_size < 0)
+ return block_size;
+
+ if (want_typ != BLOCK_TYPE_ANY && block_typ != want_typ) {
+ reftable_block_done(&block);
+ return 1;
+ }
+
+ if (block_size > guess_block_size) {
+ reftable_block_done(&block);
+ err = reader_get_block(r, &block, next_off, block_size);
+ if (err < 0) {
+ return err;
+ }
+ }
+
+ return block_reader_init(br, &block, header_off, r->block_size,
+ hash_size(r->hash_id));
+}
+
+static int table_iter_next_block(struct table_iter *dest,
+ struct table_iter *src)
+{
+ uint64_t next_block_off = src->block_off + src->bi.br->full_block_size;
+ struct block_reader br = { 0 };
+ int err = 0;
+
+ dest->r = src->r;
+ dest->typ = src->typ;
+ dest->block_off = next_block_off;
+
+ err = reader_init_block_reader(src->r, &br, next_block_off, src->typ);
+ if (err > 0) {
+ dest->is_finished = 1;
+ return 1;
+ }
+ if (err != 0)
+ return err;
+ else {
+ struct block_reader *brp =
+ reftable_malloc(sizeof(struct block_reader));
+ *brp = br;
+
+ dest->is_finished = 0;
+ block_reader_start(brp, &dest->bi);
+ }
+ return 0;
+}
+
+static int table_iter_next(struct table_iter *ti, struct reftable_record *rec)
+{
+ if (reftable_record_type(rec) != ti->typ)
+ return REFTABLE_API_ERROR;
+
+ while (1) {
+ struct table_iter next = TABLE_ITER_INIT;
+ int err = 0;
+ if (ti->is_finished) {
+ return 1;
+ }
+
+ err = table_iter_next_in_block(ti, rec);
+ if (err <= 0) {
+ return err;
+ }
+
+ err = table_iter_next_block(&next, ti);
+ if (err != 0) {
+ ti->is_finished = 1;
+ }
+ table_iter_block_done(ti);
+ if (err != 0) {
+ return err;
+ }
+ table_iter_copy_from(ti, &next);
+ block_iter_close(&next.bi);
+ }
+}
+
+static int table_iter_next_void(void *ti, struct reftable_record *rec)
+{
+ return table_iter_next(ti, rec);
+}
+
+static void table_iter_close(void *p)
+{
+ struct table_iter *ti = p;
+ table_iter_block_done(ti);
+ block_iter_close(&ti->bi);
+}
+
+static struct reftable_iterator_vtable table_iter_vtable = {
+ .next = &table_iter_next_void,
+ .close = &table_iter_close,
+};
+
+static void iterator_from_table_iter(struct reftable_iterator *it,
+ struct table_iter *ti)
+{
+ assert(!it->ops);
+ it->iter_arg = ti;
+ it->ops = &table_iter_vtable;
+}
+
+static int reader_table_iter_at(struct reftable_reader *r,
+ struct table_iter *ti, uint64_t off,
+ uint8_t typ)
+{
+ struct block_reader br = { 0 };
+ struct block_reader *brp = NULL;
+
+ int err = reader_init_block_reader(r, &br, off, typ);
+ if (err != 0)
+ return err;
+
+ brp = reftable_malloc(sizeof(struct block_reader));
+ *brp = br;
+ ti->r = r;
+ ti->typ = block_reader_type(brp);
+ ti->block_off = off;
+ block_reader_start(brp, &ti->bi);
+ return 0;
+}
+
+static int reader_start(struct reftable_reader *r, struct table_iter *ti,
+ uint8_t typ, int index)
+{
+ struct reftable_reader_offsets *offs = reader_offsets_for(r, typ);
+ uint64_t off = offs->offset;
+ if (index) {
+ off = offs->index_offset;
+ if (off == 0) {
+ return 1;
+ }
+ typ = BLOCK_TYPE_INDEX;
+ }
+
+ return reader_table_iter_at(r, ti, off, typ);
+}
+
+static int reader_seek_linear(struct reftable_reader *r, struct table_iter *ti,
+ struct reftable_record *want)
+{
+ struct reftable_record rec =
+ reftable_new_record(reftable_record_type(want));
+ struct strbuf want_key = STRBUF_INIT;
+ struct strbuf got_key = STRBUF_INIT;
+ struct table_iter next = TABLE_ITER_INIT;
+ int err = -1;
+
+ reftable_record_key(want, &want_key);
+
+ while (1) {
+ err = table_iter_next_block(&next, ti);
+ if (err < 0)
+ goto done;
+
+ if (err > 0) {
+ break;
+ }
+
+ err = block_reader_first_key(next.bi.br, &got_key);
+ if (err < 0)
+ goto done;
+
+ if (strbuf_cmp(&got_key, &want_key) > 0) {
+ table_iter_block_done(&next);
+ break;
+ }
+
+ table_iter_block_done(ti);
+ table_iter_copy_from(ti, &next);
+ }
+
+ err = block_iter_seek(&ti->bi, &want_key);
+ if (err < 0)
+ goto done;
+ err = 0;
+
+done:
+ block_iter_close(&next.bi);
+ reftable_record_destroy(&rec);
+ strbuf_release(&want_key);
+ strbuf_release(&got_key);
+ return err;
+}
+
+static int reader_seek_indexed(struct reftable_reader *r,
+ struct reftable_iterator *it,
+ struct reftable_record *rec)
+{
+ struct reftable_index_record want_index = { .last_key = STRBUF_INIT };
+ struct reftable_record want_index_rec = { NULL };
+ struct reftable_index_record index_result = { .last_key = STRBUF_INIT };
+ struct reftable_record index_result_rec = { NULL };
+ struct table_iter index_iter = TABLE_ITER_INIT;
+ struct table_iter next = TABLE_ITER_INIT;
+ int err = 0;
+
+ reftable_record_key(rec, &want_index.last_key);
+ reftable_record_from_index(&want_index_rec, &want_index);
+ reftable_record_from_index(&index_result_rec, &index_result);
+
+ err = reader_start(r, &index_iter, reftable_record_type(rec), 1);
+ if (err < 0)
+ goto done;
+
+ err = reader_seek_linear(r, &index_iter, &want_index_rec);
+ while (1) {
+ err = table_iter_next(&index_iter, &index_result_rec);
+ table_iter_block_done(&index_iter);
+ if (err != 0)
+ goto done;
+
+ err = reader_table_iter_at(r, &next, index_result.offset, 0);
+ if (err != 0)
+ goto done;
+
+ err = block_iter_seek(&next.bi, &want_index.last_key);
+ if (err < 0)
+ goto done;
+
+ if (next.typ == reftable_record_type(rec)) {
+ err = 0;
+ break;
+ }
+
+ if (next.typ != BLOCK_TYPE_INDEX) {
+ err = REFTABLE_FORMAT_ERROR;
+ break;
+ }
+
+ table_iter_copy_from(&index_iter, &next);
+ }
+
+ if (err == 0) {
+ struct table_iter empty = TABLE_ITER_INIT;
+ struct table_iter *malloced =
+ reftable_calloc(sizeof(struct table_iter));
+ *malloced = empty;
+ table_iter_copy_from(malloced, &next);
+ iterator_from_table_iter(it, malloced);
+ }
+done:
+ block_iter_close(&next.bi);
+ table_iter_close(&index_iter);
+ reftable_record_release(&want_index_rec);
+ reftable_record_release(&index_result_rec);
+ return err;
+}
+
+static int reader_seek_internal(struct reftable_reader *r,
+ struct reftable_iterator *it,
+ struct reftable_record *rec)
+{
+ struct reftable_reader_offsets *offs =
+ reader_offsets_for(r, reftable_record_type(rec));
+ uint64_t idx = offs->index_offset;
+ struct table_iter ti = TABLE_ITER_INIT;
+ int err = 0;
+ if (idx > 0)
+ return reader_seek_indexed(r, it, rec);
+
+ err = reader_start(r, &ti, reftable_record_type(rec), 0);
+ if (err < 0)
+ return err;
+ err = reader_seek_linear(r, &ti, rec);
+ if (err < 0)
+ return err;
+ else {
+ struct table_iter *p =
+ reftable_malloc(sizeof(struct table_iter));
+ *p = ti;
+ iterator_from_table_iter(it, p);
+ }
+
+ return 0;
+}
+
+int reader_seek(struct reftable_reader *r, struct reftable_iterator *it,
+ struct reftable_record *rec)
+{
+ uint8_t typ = reftable_record_type(rec);
+
+ struct reftable_reader_offsets *offs = reader_offsets_for(r, typ);
+ if (!offs->is_present) {
+ iterator_set_empty(it);
+ return 0;
+ }
+
+ return reader_seek_internal(r, it, rec);
+}
+
+int reftable_reader_seek_ref(struct reftable_reader *r,
+ struct reftable_iterator *it, const char *name)
+{
+ struct reftable_ref_record ref = {
+ .refname = (char *)name,
+ };
+ struct reftable_record rec = { NULL };
+ reftable_record_from_ref(&rec, &ref);
+ return reader_seek(r, it, &rec);
+}
+
+int reftable_reader_seek_log_at(struct reftable_reader *r,
+ struct reftable_iterator *it, const char *name,
+ uint64_t update_index)
+{
+ struct reftable_log_record log = {
+ .refname = (char *)name,
+ .update_index = update_index,
+ };
+ struct reftable_record rec = { NULL };
+ reftable_record_from_log(&rec, &log);
+ return reader_seek(r, it, &rec);
+}
+
+int reftable_reader_seek_log(struct reftable_reader *r,
+ struct reftable_iterator *it, const char *name)
+{
+ uint64_t max = ~((uint64_t)0);
+ return reftable_reader_seek_log_at(r, it, name, max);
+}
+
+void reader_close(struct reftable_reader *r)
+{
+ block_source_close(&r->source);
+ FREE_AND_NULL(r->name);
+}
+
+int reftable_new_reader(struct reftable_reader **p,
+ struct reftable_block_source *src, char const *name)
+{
+ struct reftable_reader *rd =
+ reftable_calloc(sizeof(struct reftable_reader));
+ int err = init_reader(rd, src, name);
+ if (err == 0) {
+ *p = rd;
+ } else {
+ block_source_close(src);
+ reftable_free(rd);
+ }
+ return err;
+}
+
+void reftable_reader_free(struct reftable_reader *r)
+{
+ reader_close(r);
+ reftable_free(r);
+}
+
+static int reftable_reader_refs_for_indexed(struct reftable_reader *r,
+ struct reftable_iterator *it,
+ uint8_t *oid)
+{
+ struct reftable_obj_record want = {
+ .hash_prefix = oid,
+ .hash_prefix_len = r->object_id_len,
+ };
+ struct reftable_record want_rec = { NULL };
+ struct reftable_iterator oit = { NULL };
+ struct reftable_obj_record got = { NULL };
+ struct reftable_record got_rec = { NULL };
+ int err = 0;
+ struct indexed_table_ref_iter *itr = NULL;
+
+ /* Look through the reverse index. */
+ reftable_record_from_obj(&want_rec, &want);
+ err = reader_seek(r, &oit, &want_rec);
+ if (err != 0)
+ goto done;
+
+ /* read out the reftable_obj_record */
+ reftable_record_from_obj(&got_rec, &got);
+ err = iterator_next(&oit, &got_rec);
+ if (err < 0)
+ goto done;
+
+ if (err > 0 ||
+ memcmp(want.hash_prefix, got.hash_prefix, r->object_id_len)) {
+ /* didn't find it; return empty iterator */
+ iterator_set_empty(it);
+ err = 0;
+ goto done;
+ }
+
+ err = new_indexed_table_ref_iter(&itr, r, oid, hash_size(r->hash_id),
+ got.offsets, got.offset_len);
+ if (err < 0)
+ goto done;
+ got.offsets = NULL;
+ iterator_from_indexed_table_ref_iter(it, itr);
+
+done:
+ reftable_iterator_destroy(&oit);
+ reftable_record_release(&got_rec);
+ return err;
+}
+
+static int reftable_reader_refs_for_unindexed(struct reftable_reader *r,
+ struct reftable_iterator *it,
+ uint8_t *oid)
+{
+ struct table_iter ti_empty = TABLE_ITER_INIT;
+ struct table_iter *ti = reftable_calloc(sizeof(struct table_iter));
+ struct filtering_ref_iterator *filter = NULL;
+ struct filtering_ref_iterator empty = FILTERING_REF_ITERATOR_INIT;
+ int oid_len = hash_size(r->hash_id);
+ int err;
+
+ *ti = ti_empty;
+ err = reader_start(r, ti, BLOCK_TYPE_REF, 0);
+ if (err < 0) {
+ reftable_free(ti);
+ return err;
+ }
+
+ filter = reftable_malloc(sizeof(struct filtering_ref_iterator));
+ *filter = empty;
+
+ strbuf_add(&filter->oid, oid, oid_len);
+ reftable_table_from_reader(&filter->tab, r);
+ filter->double_check = 0;
+ iterator_from_table_iter(&filter->it, ti);
+
+ iterator_from_filtering_ref_iterator(it, filter);
+ return 0;
+}
+
+int reftable_reader_refs_for(struct reftable_reader *r,
+ struct reftable_iterator *it, uint8_t *oid)
+{
+ if (r->obj_offsets.is_present)
+ return reftable_reader_refs_for_indexed(r, it, oid);
+ return reftable_reader_refs_for_unindexed(r, it, oid);
+}
+
+uint64_t reftable_reader_max_update_index(struct reftable_reader *r)
+{
+ return r->max_update_index;
+}
+
+uint64_t reftable_reader_min_update_index(struct reftable_reader *r)
+{
+ return r->min_update_index;
+}
+
+/* generic table interface. */
+
+static int reftable_reader_seek_void(void *tab, struct reftable_iterator *it,
+ struct reftable_record *rec)
+{
+ return reader_seek(tab, it, rec);
+}
+
+static uint32_t reftable_reader_hash_id_void(void *tab)
+{
+ return reftable_reader_hash_id(tab);
+}
+
+static uint64_t reftable_reader_min_update_index_void(void *tab)
+{
+ return reftable_reader_min_update_index(tab);
+}
+
+static uint64_t reftable_reader_max_update_index_void(void *tab)
+{
+ return reftable_reader_max_update_index(tab);
+}
+
+static struct reftable_table_vtable reader_vtable = {
+ .seek_record = reftable_reader_seek_void,
+ .hash_id = reftable_reader_hash_id_void,
+ .min_update_index = reftable_reader_min_update_index_void,
+ .max_update_index = reftable_reader_max_update_index_void,
+};
+
+void reftable_table_from_reader(struct reftable_table *tab,
+ struct reftable_reader *reader)
+{
+ assert(!tab->ops);
+ tab->ops = &reader_vtable;
+ tab->table_arg = reader;
+}
+
+
+int reftable_reader_print_file(const char *tablename)
+{
+ struct reftable_block_source src = { NULL };
+ int err = reftable_block_source_from_file(&src, tablename);
+ struct reftable_reader *r = NULL;
+ struct reftable_table tab = { NULL };
+ if (err < 0)
+ goto done;
+
+ err = reftable_new_reader(&r, &src, tablename);
+ if (err < 0)
+ goto done;
+
+ reftable_table_from_reader(&tab, r);
+ err = reftable_table_print(&tab);
+done:
+ reftable_reader_free(r);
+ return err;
+}
diff --git a/reftable/reader.h b/reftable/reader.h
new file mode 100644
index 0000000..39583e5
--- /dev/null
+++ b/reftable/reader.h
@@ -0,0 +1,66 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef READER_H
+#define READER_H
+
+#include "block.h"
+#include "record.h"
+#include "reftable-iterator.h"
+#include "reftable-reader.h"
+
+uint64_t block_source_size(struct reftable_block_source *source);
+
+int block_source_read_block(struct reftable_block_source *source,
+ struct reftable_block *dest, uint64_t off,
+ uint32_t size);
+void block_source_close(struct reftable_block_source *source);
+
+/* metadata for a block type */
+struct reftable_reader_offsets {
+ int is_present;
+ uint64_t offset;
+ uint64_t index_offset;
+};
+
+/* The state for reading a reftable file. */
+struct reftable_reader {
+ /* for convience, associate a name with the instance. */
+ char *name;
+ struct reftable_block_source source;
+
+ /* Size of the file, excluding the footer. */
+ uint64_t size;
+
+ /* 'sha1' for SHA1, 's256' for SHA-256 */
+ uint32_t hash_id;
+
+ uint32_t block_size;
+ uint64_t min_update_index;
+ uint64_t max_update_index;
+ /* Length of the OID keys in the 'o' section */
+ int object_id_len;
+ int version;
+
+ struct reftable_reader_offsets ref_offsets;
+ struct reftable_reader_offsets obj_offsets;
+ struct reftable_reader_offsets log_offsets;
+};
+
+int init_reader(struct reftable_reader *r, struct reftable_block_source *source,
+ const char *name);
+int reader_seek(struct reftable_reader *r, struct reftable_iterator *it,
+ struct reftable_record *rec);
+void reader_close(struct reftable_reader *r);
+const char *reader_name(struct reftable_reader *r);
+
+/* initialize a block reader to read from `r` */
+int reader_init_block_reader(struct reftable_reader *r, struct block_reader *br,
+ uint64_t next_off, uint8_t want_typ);
+
+#endif
diff --git a/reftable/readwrite_test.c b/reftable/readwrite_test.c
new file mode 100644
index 0000000..42ca48f
--- /dev/null
+++ b/reftable/readwrite_test.c
@@ -0,0 +1,650 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "system.h"
+
+#include "basics.h"
+#include "block.h"
+#include "blocksource.h"
+#include "constants.h"
+#include "reader.h"
+#include "record.h"
+#include "test_framework.h"
+#include "reftable-tests.h"
+#include "reftable-writer.h"
+
+static const int update_index = 5;
+
+static void test_buffer(void)
+{
+ struct strbuf buf = STRBUF_INIT;
+ struct reftable_block_source source = { NULL };
+ struct reftable_block out = { NULL };
+ int n;
+ uint8_t in[] = "hello";
+ strbuf_add(&buf, in, sizeof(in));
+ block_source_from_strbuf(&source, &buf);
+ EXPECT(block_source_size(&source) == 6);
+ n = block_source_read_block(&source, &out, 0, sizeof(in));
+ EXPECT(n == sizeof(in));
+ EXPECT(!memcmp(in, out.data, n));
+ reftable_block_done(&out);
+
+ n = block_source_read_block(&source, &out, 1, 2);
+ EXPECT(n == 2);
+ EXPECT(!memcmp(out.data, "el", 2));
+
+ reftable_block_done(&out);
+ block_source_close(&source);
+ strbuf_release(&buf);
+}
+
+static void write_table(char ***names, struct strbuf *buf, int N,
+ int block_size, uint32_t hash_id)
+{
+ struct reftable_write_options opts = {
+ .block_size = block_size,
+ .hash_id = hash_id,
+ };
+ struct reftable_writer *w =
+ reftable_new_writer(&strbuf_add_void, buf, &opts);
+ struct reftable_ref_record ref = { NULL };
+ int i = 0, n;
+ struct reftable_log_record log = { NULL };
+ const struct reftable_stats *stats = NULL;
+ *names = reftable_calloc(sizeof(char *) * (N + 1));
+ reftable_writer_set_limits(w, update_index, update_index);
+ for (i = 0; i < N; i++) {
+ uint8_t hash[GIT_SHA256_RAWSZ] = { 0 };
+ char name[100];
+ int n;
+
+ set_test_hash(hash, i);
+
+ snprintf(name, sizeof(name), "refs/heads/branch%02d", i);
+
+ ref.refname = name;
+ ref.update_index = update_index;
+ ref.value_type = REFTABLE_REF_VAL1;
+ ref.value.val1 = hash;
+ (*names)[i] = xstrdup(name);
+
+ n = reftable_writer_add_ref(w, &ref);
+ EXPECT(n == 0);
+ }
+
+ for (i = 0; i < N; i++) {
+ uint8_t hash[GIT_SHA256_RAWSZ] = { 0 };
+ char name[100];
+ int n;
+
+ set_test_hash(hash, i);
+
+ snprintf(name, sizeof(name), "refs/heads/branch%02d", i);
+
+ log.refname = name;
+ log.update_index = update_index;
+ log.value_type = REFTABLE_LOG_UPDATE;
+ log.update.new_hash = hash;
+ log.update.message = "message";
+
+ n = reftable_writer_add_log(w, &log);
+ EXPECT(n == 0);
+ }
+
+ n = reftable_writer_close(w);
+ EXPECT(n == 0);
+
+ stats = writer_stats(w);
+ for (i = 0; i < stats->ref_stats.blocks; i++) {
+ int off = i * opts.block_size;
+ if (off == 0) {
+ off = header_size((hash_id == GIT_SHA256_FORMAT_ID) ? 2 :
+ 1);
+ }
+ EXPECT(buf->buf[off] == 'r');
+ }
+
+ EXPECT(stats->log_stats.blocks > 0);
+ reftable_writer_free(w);
+}
+
+static void test_log_buffer_size(void)
+{
+ struct strbuf buf = STRBUF_INIT;
+ struct reftable_write_options opts = {
+ .block_size = 4096,
+ };
+ int err;
+ struct reftable_log_record log = { .refname = "refs/heads/master",
+ .update_index = 0xa,
+ .value_type = REFTABLE_LOG_UPDATE,
+ .update = {
+ .name = "Han-Wen Nienhuys",
+ .email = "hanwen@google.com",
+ .tz_offset = 100,
+ .time = 0x5e430672,
+ .message = "commit: 9\n",
+ } };
+ struct reftable_writer *w =
+ reftable_new_writer(&strbuf_add_void, &buf, &opts);
+
+ /* This tests buffer extension for log compression. Must use a random
+ hash, to ensure that the compressed part is larger than the original.
+ */
+ uint8_t hash1[GIT_SHA1_RAWSZ], hash2[GIT_SHA1_RAWSZ];
+ for (int i = 0; i < GIT_SHA1_RAWSZ; i++) {
+ hash1[i] = (uint8_t)(rand() % 256);
+ hash2[i] = (uint8_t)(rand() % 256);
+ }
+ log.update.old_hash = hash1;
+ log.update.new_hash = hash2;
+ reftable_writer_set_limits(w, update_index, update_index);
+ err = reftable_writer_add_log(w, &log);
+ EXPECT_ERR(err);
+ err = reftable_writer_close(w);
+ EXPECT_ERR(err);
+ reftable_writer_free(w);
+ strbuf_release(&buf);
+}
+
+static void test_log_write_read(void)
+{
+ int N = 2;
+ char **names = reftable_calloc(sizeof(char *) * (N + 1));
+ int err;
+ struct reftable_write_options opts = {
+ .block_size = 256,
+ };
+ struct reftable_ref_record ref = { NULL };
+ int i = 0;
+ struct reftable_log_record log = { NULL };
+ int n;
+ struct reftable_iterator it = { NULL };
+ struct reftable_reader rd = { NULL };
+ struct reftable_block_source source = { NULL };
+ struct strbuf buf = STRBUF_INIT;
+ struct reftable_writer *w =
+ reftable_new_writer(&strbuf_add_void, &buf, &opts);
+ const struct reftable_stats *stats = NULL;
+ reftable_writer_set_limits(w, 0, N);
+ for (i = 0; i < N; i++) {
+ char name[256];
+ struct reftable_ref_record ref = { NULL };
+ snprintf(name, sizeof(name), "b%02d%0*d", i, 130, 7);
+ names[i] = xstrdup(name);
+ ref.refname = name;
+ ref.update_index = i;
+
+ err = reftable_writer_add_ref(w, &ref);
+ EXPECT_ERR(err);
+ }
+ for (i = 0; i < N; i++) {
+ uint8_t hash1[GIT_SHA1_RAWSZ], hash2[GIT_SHA1_RAWSZ];
+ struct reftable_log_record log = { NULL };
+ set_test_hash(hash1, i);
+ set_test_hash(hash2, i + 1);
+
+ log.refname = names[i];
+ log.update_index = i;
+ log.value_type = REFTABLE_LOG_UPDATE;
+ log.update.old_hash = hash1;
+ log.update.new_hash = hash2;
+
+ err = reftable_writer_add_log(w, &log);
+ EXPECT_ERR(err);
+ }
+
+ n = reftable_writer_close(w);
+ EXPECT(n == 0);
+
+ stats = writer_stats(w);
+ EXPECT(stats->log_stats.blocks > 0);
+ reftable_writer_free(w);
+ w = NULL;
+
+ block_source_from_strbuf(&source, &buf);
+
+ err = init_reader(&rd, &source, "file.log");
+ EXPECT_ERR(err);
+
+ err = reftable_reader_seek_ref(&rd, &it, names[N - 1]);
+ EXPECT_ERR(err);
+
+ err = reftable_iterator_next_ref(&it, &ref);
+ EXPECT_ERR(err);
+
+ /* end of iteration. */
+ err = reftable_iterator_next_ref(&it, &ref);
+ EXPECT(0 < err);
+
+ reftable_iterator_destroy(&it);
+ reftable_ref_record_release(&ref);
+
+ err = reftable_reader_seek_log(&rd, &it, "");
+ EXPECT_ERR(err);
+
+ i = 0;
+ while (1) {
+ int err = reftable_iterator_next_log(&it, &log);
+ if (err > 0) {
+ break;
+ }
+
+ EXPECT_ERR(err);
+ EXPECT_STREQ(names[i], log.refname);
+ EXPECT(i == log.update_index);
+ i++;
+ reftable_log_record_release(&log);
+ }
+
+ EXPECT(i == N);
+ reftable_iterator_destroy(&it);
+
+ /* cleanup. */
+ strbuf_release(&buf);
+ free_names(names);
+ reader_close(&rd);
+}
+
+static void test_table_read_write_sequential(void)
+{
+ char **names;
+ struct strbuf buf = STRBUF_INIT;
+ int N = 50;
+ struct reftable_iterator it = { NULL };
+ struct reftable_block_source source = { NULL };
+ struct reftable_reader rd = { NULL };
+ int err = 0;
+ int j = 0;
+
+ write_table(&names, &buf, N, 256, GIT_SHA1_FORMAT_ID);
+
+ block_source_from_strbuf(&source, &buf);
+
+ err = init_reader(&rd, &source, "file.ref");
+ EXPECT_ERR(err);
+
+ err = reftable_reader_seek_ref(&rd, &it, "");
+ EXPECT_ERR(err);
+
+ while (1) {
+ struct reftable_ref_record ref = { NULL };
+ int r = reftable_iterator_next_ref(&it, &ref);
+ EXPECT(r >= 0);
+ if (r > 0) {
+ break;
+ }
+ EXPECT(0 == strcmp(names[j], ref.refname));
+ EXPECT(update_index == ref.update_index);
+
+ j++;
+ reftable_ref_record_release(&ref);
+ }
+ EXPECT(j == N);
+ reftable_iterator_destroy(&it);
+ strbuf_release(&buf);
+ free_names(names);
+
+ reader_close(&rd);
+}
+
+static void test_table_write_small_table(void)
+{
+ char **names;
+ struct strbuf buf = STRBUF_INIT;
+ int N = 1;
+ write_table(&names, &buf, N, 4096, GIT_SHA1_FORMAT_ID);
+ EXPECT(buf.len < 200);
+ strbuf_release(&buf);
+ free_names(names);
+}
+
+static void test_table_read_api(void)
+{
+ char **names;
+ struct strbuf buf = STRBUF_INIT;
+ int N = 50;
+ struct reftable_reader rd = { NULL };
+ struct reftable_block_source source = { NULL };
+ int err;
+ int i;
+ struct reftable_log_record log = { NULL };
+ struct reftable_iterator it = { NULL };
+
+ write_table(&names, &buf, N, 256, GIT_SHA1_FORMAT_ID);
+
+ block_source_from_strbuf(&source, &buf);
+
+ err = init_reader(&rd, &source, "file.ref");
+ EXPECT_ERR(err);
+
+ err = reftable_reader_seek_ref(&rd, &it, names[0]);
+ EXPECT_ERR(err);
+
+ err = reftable_iterator_next_log(&it, &log);
+ EXPECT(err == REFTABLE_API_ERROR);
+
+ strbuf_release(&buf);
+ for (i = 0; i < N; i++) {
+ reftable_free(names[i]);
+ }
+ reftable_iterator_destroy(&it);
+ reftable_free(names);
+ reader_close(&rd);
+ strbuf_release(&buf);
+}
+
+static void test_table_read_write_seek(int index, int hash_id)
+{
+ char **names;
+ struct strbuf buf = STRBUF_INIT;
+ int N = 50;
+ struct reftable_reader rd = { NULL };
+ struct reftable_block_source source = { NULL };
+ int err;
+ int i = 0;
+
+ struct reftable_iterator it = { NULL };
+ struct strbuf pastLast = STRBUF_INIT;
+ struct reftable_ref_record ref = { NULL };
+
+ write_table(&names, &buf, N, 256, hash_id);
+
+ block_source_from_strbuf(&source, &buf);
+
+ err = init_reader(&rd, &source, "file.ref");
+ EXPECT_ERR(err);
+ EXPECT(hash_id == reftable_reader_hash_id(&rd));
+
+ if (!index) {
+ rd.ref_offsets.index_offset = 0;
+ } else {
+ EXPECT(rd.ref_offsets.index_offset > 0);
+ }
+
+ for (i = 1; i < N; i++) {
+ int err = reftable_reader_seek_ref(&rd, &it, names[i]);
+ EXPECT_ERR(err);
+ err = reftable_iterator_next_ref(&it, &ref);
+ EXPECT_ERR(err);
+ EXPECT(0 == strcmp(names[i], ref.refname));
+ EXPECT(REFTABLE_REF_VAL1 == ref.value_type);
+ EXPECT(i == ref.value.val1[0]);
+
+ reftable_ref_record_release(&ref);
+ reftable_iterator_destroy(&it);
+ }
+
+ strbuf_addstr(&pastLast, names[N - 1]);
+ strbuf_addstr(&pastLast, "/");
+
+ err = reftable_reader_seek_ref(&rd, &it, pastLast.buf);
+ if (err == 0) {
+ struct reftable_ref_record ref = { NULL };
+ int err = reftable_iterator_next_ref(&it, &ref);
+ EXPECT(err > 0);
+ } else {
+ EXPECT(err > 0);
+ }
+
+ strbuf_release(&pastLast);
+ reftable_iterator_destroy(&it);
+
+ strbuf_release(&buf);
+ for (i = 0; i < N; i++) {
+ reftable_free(names[i]);
+ }
+ reftable_free(names);
+ reader_close(&rd);
+}
+
+static void test_table_read_write_seek_linear(void)
+{
+ test_table_read_write_seek(0, GIT_SHA1_FORMAT_ID);
+}
+
+static void test_table_read_write_seek_linear_sha256(void)
+{
+ test_table_read_write_seek(0, GIT_SHA256_FORMAT_ID);
+}
+
+static void test_table_read_write_seek_index(void)
+{
+ test_table_read_write_seek(1, GIT_SHA1_FORMAT_ID);
+}
+
+static void test_table_refs_for(int indexed)
+{
+ int N = 50;
+ char **want_names = reftable_calloc(sizeof(char *) * (N + 1));
+ int want_names_len = 0;
+ uint8_t want_hash[GIT_SHA1_RAWSZ];
+
+ struct reftable_write_options opts = {
+ .block_size = 256,
+ };
+ struct reftable_ref_record ref = { NULL };
+ int i = 0;
+ int n;
+ int err;
+ struct reftable_reader rd;
+ struct reftable_block_source source = { NULL };
+
+ struct strbuf buf = STRBUF_INIT;
+ struct reftable_writer *w =
+ reftable_new_writer(&strbuf_add_void, &buf, &opts);
+
+ struct reftable_iterator it = { NULL };
+ int j;
+
+ set_test_hash(want_hash, 4);
+
+ for (i = 0; i < N; i++) {
+ uint8_t hash[GIT_SHA1_RAWSZ];
+ char fill[51] = { 0 };
+ char name[100];
+ uint8_t hash1[GIT_SHA1_RAWSZ];
+ uint8_t hash2[GIT_SHA1_RAWSZ];
+ struct reftable_ref_record ref = { NULL };
+
+ memset(hash, i, sizeof(hash));
+ memset(fill, 'x', 50);
+ /* Put the variable part in the start */
+ snprintf(name, sizeof(name), "br%02d%s", i, fill);
+ name[40] = 0;
+ ref.refname = name;
+
+ set_test_hash(hash1, i / 4);
+ set_test_hash(hash2, 3 + i / 4);
+ ref.value_type = REFTABLE_REF_VAL2;
+ ref.value.val2.value = hash1;
+ ref.value.val2.target_value = hash2;
+
+ /* 80 bytes / entry, so 3 entries per block. Yields 17
+ */
+ /* blocks. */
+ n = reftable_writer_add_ref(w, &ref);
+ EXPECT(n == 0);
+
+ if (!memcmp(hash1, want_hash, GIT_SHA1_RAWSZ) ||
+ !memcmp(hash2, want_hash, GIT_SHA1_RAWSZ)) {
+ want_names[want_names_len++] = xstrdup(name);
+ }
+ }
+
+ n = reftable_writer_close(w);
+ EXPECT(n == 0);
+
+ reftable_writer_free(w);
+ w = NULL;
+
+ block_source_from_strbuf(&source, &buf);
+
+ err = init_reader(&rd, &source, "file.ref");
+ EXPECT_ERR(err);
+ if (!indexed) {
+ rd.obj_offsets.is_present = 0;
+ }
+
+ err = reftable_reader_seek_ref(&rd, &it, "");
+ EXPECT_ERR(err);
+ reftable_iterator_destroy(&it);
+
+ err = reftable_reader_refs_for(&rd, &it, want_hash);
+ EXPECT_ERR(err);
+
+ j = 0;
+ while (1) {
+ int err = reftable_iterator_next_ref(&it, &ref);
+ EXPECT(err >= 0);
+ if (err > 0) {
+ break;
+ }
+
+ EXPECT(j < want_names_len);
+ EXPECT(0 == strcmp(ref.refname, want_names[j]));
+ j++;
+ reftable_ref_record_release(&ref);
+ }
+ EXPECT(j == want_names_len);
+
+ strbuf_release(&buf);
+ free_names(want_names);
+ reftable_iterator_destroy(&it);
+ reader_close(&rd);
+}
+
+static void test_table_refs_for_no_index(void)
+{
+ test_table_refs_for(0);
+}
+
+static void test_table_refs_for_obj_index(void)
+{
+ test_table_refs_for(1);
+}
+
+static void test_write_empty_table(void)
+{
+ struct reftable_write_options opts = { 0 };
+ struct strbuf buf = STRBUF_INIT;
+ struct reftable_writer *w =
+ reftable_new_writer(&strbuf_add_void, &buf, &opts);
+ struct reftable_block_source source = { NULL };
+ struct reftable_reader *rd = NULL;
+ struct reftable_ref_record rec = { NULL };
+ struct reftable_iterator it = { NULL };
+ int err;
+
+ reftable_writer_set_limits(w, 1, 1);
+
+ err = reftable_writer_close(w);
+ EXPECT(err == REFTABLE_EMPTY_TABLE_ERROR);
+ reftable_writer_free(w);
+
+ EXPECT(buf.len == header_size(1) + footer_size(1));
+
+ block_source_from_strbuf(&source, &buf);
+
+ err = reftable_new_reader(&rd, &source, "filename");
+ EXPECT_ERR(err);
+
+ err = reftable_reader_seek_ref(rd, &it, "");
+ EXPECT_ERR(err);
+
+ err = reftable_iterator_next_ref(&it, &rec);
+ EXPECT(err > 0);
+
+ reftable_iterator_destroy(&it);
+ reftable_reader_free(rd);
+ strbuf_release(&buf);
+}
+
+static void test_write_key_order(void)
+{
+ struct reftable_write_options opts = { 0 };
+ struct strbuf buf = STRBUF_INIT;
+ struct reftable_writer *w =
+ reftable_new_writer(&strbuf_add_void, &buf, &opts);
+ struct reftable_ref_record refs[2] = {
+ {
+ .refname = "b",
+ .update_index = 1,
+ .value_type = REFTABLE_REF_SYMREF,
+ .value = {
+ .symref = "target",
+ },
+ }, {
+ .refname = "a",
+ .update_index = 1,
+ .value_type = REFTABLE_REF_SYMREF,
+ .value = {
+ .symref = "target",
+ },
+ }
+ };
+ int err;
+
+ reftable_writer_set_limits(w, 1, 1);
+ err = reftable_writer_add_ref(w, &refs[0]);
+ EXPECT_ERR(err);
+ err = reftable_writer_add_ref(w, &refs[1]);
+ printf("%d\n", err);
+ EXPECT(err == REFTABLE_API_ERROR);
+ reftable_writer_close(w);
+ reftable_writer_free(w);
+ strbuf_release(&buf);
+}
+
+static void test_corrupt_table_empty(void)
+{
+ struct strbuf buf = STRBUF_INIT;
+ struct reftable_block_source source = { NULL };
+ struct reftable_reader rd = { NULL };
+ int err;
+
+ block_source_from_strbuf(&source, &buf);
+ err = init_reader(&rd, &source, "file.log");
+ EXPECT(err == REFTABLE_FORMAT_ERROR);
+}
+
+static void test_corrupt_table(void)
+{
+ uint8_t zeros[1024] = { 0 };
+ struct strbuf buf = STRBUF_INIT;
+ struct reftable_block_source source = { NULL };
+ struct reftable_reader rd = { NULL };
+ int err;
+ strbuf_add(&buf, zeros, sizeof(zeros));
+
+ block_source_from_strbuf(&source, &buf);
+ err = init_reader(&rd, &source, "file.log");
+ EXPECT(err == REFTABLE_FORMAT_ERROR);
+ strbuf_release(&buf);
+}
+
+int readwrite_test_main(int argc, const char *argv[])
+{
+ RUN_TEST(test_corrupt_table);
+ RUN_TEST(test_corrupt_table_empty);
+ RUN_TEST(test_log_write_read);
+ RUN_TEST(test_write_key_order);
+ RUN_TEST(test_table_read_write_seek_linear_sha256);
+ RUN_TEST(test_log_buffer_size);
+ RUN_TEST(test_table_write_small_table);
+ RUN_TEST(test_buffer);
+ RUN_TEST(test_table_read_api);
+ RUN_TEST(test_table_read_write_sequential);
+ RUN_TEST(test_table_read_write_seek_linear);
+ RUN_TEST(test_table_read_write_seek_index);
+ RUN_TEST(test_table_refs_for_no_index);
+ RUN_TEST(test_table_refs_for_obj_index);
+ RUN_TEST(test_write_empty_table);
+ return 0;
+}
diff --git a/reftable/record.c b/reftable/record.c
new file mode 100644
index 0000000..34ed480
--- /dev/null
+++ b/reftable/record.c
@@ -0,0 +1,1200 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+/* record.c - methods for different types of records. */
+
+#include "record.h"
+
+#include "system.h"
+#include "constants.h"
+#include "reftable-error.h"
+#include "basics.h"
+
+int get_var_int(uint64_t *dest, struct string_view *in)
+{
+ int ptr = 0;
+ uint64_t val;
+
+ if (in->len == 0)
+ return -1;
+ val = in->buf[ptr] & 0x7f;
+
+ while (in->buf[ptr] & 0x80) {
+ ptr++;
+ if (ptr > in->len) {
+ return -1;
+ }
+ val = (val + 1) << 7 | (uint64_t)(in->buf[ptr] & 0x7f);
+ }
+
+ *dest = val;
+ return ptr + 1;
+}
+
+int put_var_int(struct string_view *dest, uint64_t val)
+{
+ uint8_t buf[10] = { 0 };
+ int i = 9;
+ int n = 0;
+ buf[i] = (uint8_t)(val & 0x7f);
+ i--;
+ while (1) {
+ val >>= 7;
+ if (!val) {
+ break;
+ }
+ val--;
+ buf[i] = 0x80 | (uint8_t)(val & 0x7f);
+ i--;
+ }
+
+ n = sizeof(buf) - i - 1;
+ if (dest->len < n)
+ return -1;
+ memcpy(dest->buf, &buf[i + 1], n);
+ return n;
+}
+
+int reftable_is_block_type(uint8_t typ)
+{
+ switch (typ) {
+ case BLOCK_TYPE_REF:
+ case BLOCK_TYPE_LOG:
+ case BLOCK_TYPE_OBJ:
+ case BLOCK_TYPE_INDEX:
+ return 1;
+ }
+ return 0;
+}
+
+uint8_t *reftable_ref_record_val1(struct reftable_ref_record *rec)
+{
+ switch (rec->value_type) {
+ case REFTABLE_REF_VAL1:
+ return rec->value.val1;
+ case REFTABLE_REF_VAL2:
+ return rec->value.val2.value;
+ default:
+ return NULL;
+ }
+}
+
+uint8_t *reftable_ref_record_val2(struct reftable_ref_record *rec)
+{
+ switch (rec->value_type) {
+ case REFTABLE_REF_VAL2:
+ return rec->value.val2.target_value;
+ default:
+ return NULL;
+ }
+}
+
+static int decode_string(struct strbuf *dest, struct string_view in)
+{
+ int start_len = in.len;
+ uint64_t tsize = 0;
+ int n = get_var_int(&tsize, &in);
+ if (n <= 0)
+ return -1;
+ string_view_consume(&in, n);
+ if (in.len < tsize)
+ return -1;
+
+ strbuf_reset(dest);
+ strbuf_add(dest, in.buf, tsize);
+ string_view_consume(&in, tsize);
+
+ return start_len - in.len;
+}
+
+static int encode_string(char *str, struct string_view s)
+{
+ struct string_view start = s;
+ int l = strlen(str);
+ int n = put_var_int(&s, l);
+ if (n < 0)
+ return -1;
+ string_view_consume(&s, n);
+ if (s.len < l)
+ return -1;
+ memcpy(s.buf, str, l);
+ string_view_consume(&s, l);
+
+ return start.len - s.len;
+}
+
+int reftable_encode_key(int *restart, struct string_view dest,
+ struct strbuf prev_key, struct strbuf key,
+ uint8_t extra)
+{
+ struct string_view start = dest;
+ int prefix_len = common_prefix_size(&prev_key, &key);
+ uint64_t suffix_len = key.len - prefix_len;
+ int n = put_var_int(&dest, (uint64_t)prefix_len);
+ if (n < 0)
+ return -1;
+ string_view_consume(&dest, n);
+
+ *restart = (prefix_len == 0);
+
+ n = put_var_int(&dest, suffix_len << 3 | (uint64_t)extra);
+ if (n < 0)
+ return -1;
+ string_view_consume(&dest, n);
+
+ if (dest.len < suffix_len)
+ return -1;
+ memcpy(dest.buf, key.buf + prefix_len, suffix_len);
+ string_view_consume(&dest, suffix_len);
+
+ return start.len - dest.len;
+}
+
+int reftable_decode_key(struct strbuf *key, uint8_t *extra,
+ struct strbuf last_key, struct string_view in)
+{
+ int start_len = in.len;
+ uint64_t prefix_len = 0;
+ uint64_t suffix_len = 0;
+ int n = get_var_int(&prefix_len, &in);
+ if (n < 0)
+ return -1;
+ string_view_consume(&in, n);
+
+ if (prefix_len > last_key.len)
+ return -1;
+
+ n = get_var_int(&suffix_len, &in);
+ if (n <= 0)
+ return -1;
+ string_view_consume(&in, n);
+
+ *extra = (uint8_t)(suffix_len & 0x7);
+ suffix_len >>= 3;
+
+ if (in.len < suffix_len)
+ return -1;
+
+ strbuf_reset(key);
+ strbuf_add(key, last_key.buf, prefix_len);
+ strbuf_add(key, in.buf, suffix_len);
+ string_view_consume(&in, suffix_len);
+
+ return start_len - in.len;
+}
+
+static void reftable_ref_record_key(const void *r, struct strbuf *dest)
+{
+ const struct reftable_ref_record *rec =
+ (const struct reftable_ref_record *)r;
+ strbuf_reset(dest);
+ strbuf_addstr(dest, rec->refname);
+}
+
+static void reftable_ref_record_copy_from(void *rec, const void *src_rec,
+ int hash_size)
+{
+ struct reftable_ref_record *ref = rec;
+ const struct reftable_ref_record *src = src_rec;
+ assert(hash_size > 0);
+
+ /* This is simple and correct, but we could probably reuse the hash
+ * fields. */
+ reftable_ref_record_release(ref);
+ if (src->refname) {
+ ref->refname = xstrdup(src->refname);
+ }
+ ref->update_index = src->update_index;
+ ref->value_type = src->value_type;
+ switch (src->value_type) {
+ case REFTABLE_REF_DELETION:
+ break;
+ case REFTABLE_REF_VAL1:
+ ref->value.val1 = reftable_malloc(hash_size);
+ memcpy(ref->value.val1, src->value.val1, hash_size);
+ break;
+ case REFTABLE_REF_VAL2:
+ ref->value.val2.value = reftable_malloc(hash_size);
+ memcpy(ref->value.val2.value, src->value.val2.value, hash_size);
+ ref->value.val2.target_value = reftable_malloc(hash_size);
+ memcpy(ref->value.val2.target_value,
+ src->value.val2.target_value, hash_size);
+ break;
+ case REFTABLE_REF_SYMREF:
+ ref->value.symref = xstrdup(src->value.symref);
+ break;
+ }
+}
+
+static char hexdigit(int c)
+{
+ if (c <= 9)
+ return '0' + c;
+ return 'a' + (c - 10);
+}
+
+static void hex_format(char *dest, uint8_t *src, int hash_size)
+{
+ assert(hash_size > 0);
+ if (src) {
+ int i = 0;
+ for (i = 0; i < hash_size; i++) {
+ dest[2 * i] = hexdigit(src[i] >> 4);
+ dest[2 * i + 1] = hexdigit(src[i] & 0xf);
+ }
+ dest[2 * hash_size] = 0;
+ }
+}
+
+void reftable_ref_record_print(struct reftable_ref_record *ref,
+ uint32_t hash_id)
+{
+ char hex[2 * GIT_SHA256_RAWSZ + 1] = { 0 }; /* BUG */
+ printf("ref{%s(%" PRIu64 ") ", ref->refname, ref->update_index);
+ switch (ref->value_type) {
+ case REFTABLE_REF_SYMREF:
+ printf("=> %s", ref->value.symref);
+ break;
+ case REFTABLE_REF_VAL2:
+ hex_format(hex, ref->value.val2.value, hash_size(hash_id));
+ printf("val 2 %s", hex);
+ hex_format(hex, ref->value.val2.target_value,
+ hash_size(hash_id));
+ printf("(T %s)", hex);
+ break;
+ case REFTABLE_REF_VAL1:
+ hex_format(hex, ref->value.val1, hash_size(hash_id));
+ printf("val 1 %s", hex);
+ break;
+ case REFTABLE_REF_DELETION:
+ printf("delete");
+ break;
+ }
+ printf("}\n");
+}
+
+static void reftable_ref_record_release_void(void *rec)
+{
+ reftable_ref_record_release(rec);
+}
+
+void reftable_ref_record_release(struct reftable_ref_record *ref)
+{
+ switch (ref->value_type) {
+ case REFTABLE_REF_SYMREF:
+ reftable_free(ref->value.symref);
+ break;
+ case REFTABLE_REF_VAL2:
+ reftable_free(ref->value.val2.target_value);
+ reftable_free(ref->value.val2.value);
+ break;
+ case REFTABLE_REF_VAL1:
+ reftable_free(ref->value.val1);
+ break;
+ case REFTABLE_REF_DELETION:
+ break;
+ default:
+ abort();
+ }
+
+ reftable_free(ref->refname);
+ memset(ref, 0, sizeof(struct reftable_ref_record));
+}
+
+static uint8_t reftable_ref_record_val_type(const void *rec)
+{
+ const struct reftable_ref_record *r =
+ (const struct reftable_ref_record *)rec;
+ return r->value_type;
+}
+
+static int reftable_ref_record_encode(const void *rec, struct string_view s,
+ int hash_size)
+{
+ const struct reftable_ref_record *r =
+ (const struct reftable_ref_record *)rec;
+ struct string_view start = s;
+ int n = put_var_int(&s, r->update_index);
+ assert(hash_size > 0);
+ if (n < 0)
+ return -1;
+ string_view_consume(&s, n);
+
+ switch (r->value_type) {
+ case REFTABLE_REF_SYMREF:
+ n = encode_string(r->value.symref, s);
+ if (n < 0) {
+ return -1;
+ }
+ string_view_consume(&s, n);
+ break;
+ case REFTABLE_REF_VAL2:
+ if (s.len < 2 * hash_size) {
+ return -1;
+ }
+ memcpy(s.buf, r->value.val2.value, hash_size);
+ string_view_consume(&s, hash_size);
+ memcpy(s.buf, r->value.val2.target_value, hash_size);
+ string_view_consume(&s, hash_size);
+ break;
+ case REFTABLE_REF_VAL1:
+ if (s.len < hash_size) {
+ return -1;
+ }
+ memcpy(s.buf, r->value.val1, hash_size);
+ string_view_consume(&s, hash_size);
+ break;
+ case REFTABLE_REF_DELETION:
+ break;
+ default:
+ abort();
+ }
+
+ return start.len - s.len;
+}
+
+static int reftable_ref_record_decode(void *rec, struct strbuf key,
+ uint8_t val_type, struct string_view in,
+ int hash_size)
+{
+ struct reftable_ref_record *r = rec;
+ struct string_view start = in;
+ uint64_t update_index = 0;
+ int n = get_var_int(&update_index, &in);
+ if (n < 0)
+ return n;
+ string_view_consume(&in, n);
+
+ reftable_ref_record_release(r);
+
+ assert(hash_size > 0);
+
+ r->refname = reftable_realloc(r->refname, key.len + 1);
+ memcpy(r->refname, key.buf, key.len);
+ r->update_index = update_index;
+ r->refname[key.len] = 0;
+ r->value_type = val_type;
+ switch (val_type) {
+ case REFTABLE_REF_VAL1:
+ if (in.len < hash_size) {
+ return -1;
+ }
+
+ r->value.val1 = reftable_malloc(hash_size);
+ memcpy(r->value.val1, in.buf, hash_size);
+ string_view_consume(&in, hash_size);
+ break;
+
+ case REFTABLE_REF_VAL2:
+ if (in.len < 2 * hash_size) {
+ return -1;
+ }
+
+ r->value.val2.value = reftable_malloc(hash_size);
+ memcpy(r->value.val2.value, in.buf, hash_size);
+ string_view_consume(&in, hash_size);
+
+ r->value.val2.target_value = reftable_malloc(hash_size);
+ memcpy(r->value.val2.target_value, in.buf, hash_size);
+ string_view_consume(&in, hash_size);
+ break;
+
+ case REFTABLE_REF_SYMREF: {
+ struct strbuf dest = STRBUF_INIT;
+ int n = decode_string(&dest, in);
+ if (n < 0) {
+ return -1;
+ }
+ string_view_consume(&in, n);
+ r->value.symref = dest.buf;
+ } break;
+
+ case REFTABLE_REF_DELETION:
+ break;
+ default:
+ abort();
+ break;
+ }
+
+ return start.len - in.len;
+}
+
+static int reftable_ref_record_is_deletion_void(const void *p)
+{
+ return reftable_ref_record_is_deletion(
+ (const struct reftable_ref_record *)p);
+}
+
+static struct reftable_record_vtable reftable_ref_record_vtable = {
+ .key = &reftable_ref_record_key,
+ .type = BLOCK_TYPE_REF,
+ .copy_from = &reftable_ref_record_copy_from,
+ .val_type = &reftable_ref_record_val_type,
+ .encode = &reftable_ref_record_encode,
+ .decode = &reftable_ref_record_decode,
+ .release = &reftable_ref_record_release_void,
+ .is_deletion = &reftable_ref_record_is_deletion_void,
+};
+
+static void reftable_obj_record_key(const void *r, struct strbuf *dest)
+{
+ const struct reftable_obj_record *rec =
+ (const struct reftable_obj_record *)r;
+ strbuf_reset(dest);
+ strbuf_add(dest, rec->hash_prefix, rec->hash_prefix_len);
+}
+
+static void reftable_obj_record_release(void *rec)
+{
+ struct reftable_obj_record *obj = rec;
+ FREE_AND_NULL(obj->hash_prefix);
+ FREE_AND_NULL(obj->offsets);
+ memset(obj, 0, sizeof(struct reftable_obj_record));
+}
+
+static void reftable_obj_record_copy_from(void *rec, const void *src_rec,
+ int hash_size)
+{
+ struct reftable_obj_record *obj = rec;
+ const struct reftable_obj_record *src =
+ (const struct reftable_obj_record *)src_rec;
+
+ reftable_obj_record_release(obj);
+ *obj = *src;
+ obj->hash_prefix = reftable_malloc(obj->hash_prefix_len);
+ memcpy(obj->hash_prefix, src->hash_prefix, obj->hash_prefix_len);
+
+ obj->offsets = reftable_malloc(obj->offset_len * sizeof(uint64_t));
+ COPY_ARRAY(obj->offsets, src->offsets, obj->offset_len);
+}
+
+static uint8_t reftable_obj_record_val_type(const void *rec)
+{
+ const struct reftable_obj_record *r = rec;
+ if (r->offset_len > 0 && r->offset_len < 8)
+ return r->offset_len;
+ return 0;
+}
+
+static int reftable_obj_record_encode(const void *rec, struct string_view s,
+ int hash_size)
+{
+ const struct reftable_obj_record *r = rec;
+ struct string_view start = s;
+ int i = 0;
+ int n = 0;
+ uint64_t last = 0;
+ if (r->offset_len == 0 || r->offset_len >= 8) {
+ n = put_var_int(&s, r->offset_len);
+ if (n < 0) {
+ return -1;
+ }
+ string_view_consume(&s, n);
+ }
+ if (r->offset_len == 0)
+ return start.len - s.len;
+ n = put_var_int(&s, r->offsets[0]);
+ if (n < 0)
+ return -1;
+ string_view_consume(&s, n);
+
+ last = r->offsets[0];
+ for (i = 1; i < r->offset_len; i++) {
+ int n = put_var_int(&s, r->offsets[i] - last);
+ if (n < 0) {
+ return -1;
+ }
+ string_view_consume(&s, n);
+ last = r->offsets[i];
+ }
+ return start.len - s.len;
+}
+
+static int reftable_obj_record_decode(void *rec, struct strbuf key,
+ uint8_t val_type, struct string_view in,
+ int hash_size)
+{
+ struct string_view start = in;
+ struct reftable_obj_record *r = rec;
+ uint64_t count = val_type;
+ int n = 0;
+ uint64_t last;
+ int j;
+ r->hash_prefix = reftable_malloc(key.len);
+ memcpy(r->hash_prefix, key.buf, key.len);
+ r->hash_prefix_len = key.len;
+
+ if (val_type == 0) {
+ n = get_var_int(&count, &in);
+ if (n < 0) {
+ return n;
+ }
+
+ string_view_consume(&in, n);
+ }
+
+ r->offsets = NULL;
+ r->offset_len = 0;
+ if (count == 0)
+ return start.len - in.len;
+
+ r->offsets = reftable_malloc(count * sizeof(uint64_t));
+ r->offset_len = count;
+
+ n = get_var_int(&r->offsets[0], &in);
+ if (n < 0)
+ return n;
+ string_view_consume(&in, n);
+
+ last = r->offsets[0];
+ j = 1;
+ while (j < count) {
+ uint64_t delta = 0;
+ int n = get_var_int(&delta, &in);
+ if (n < 0) {
+ return n;
+ }
+ string_view_consume(&in, n);
+
+ last = r->offsets[j] = (delta + last);
+ j++;
+ }
+ return start.len - in.len;
+}
+
+static int not_a_deletion(const void *p)
+{
+ return 0;
+}
+
+static struct reftable_record_vtable reftable_obj_record_vtable = {
+ .key = &reftable_obj_record_key,
+ .type = BLOCK_TYPE_OBJ,
+ .copy_from = &reftable_obj_record_copy_from,
+ .val_type = &reftable_obj_record_val_type,
+ .encode = &reftable_obj_record_encode,
+ .decode = &reftable_obj_record_decode,
+ .release = &reftable_obj_record_release,
+ .is_deletion = not_a_deletion,
+};
+
+void reftable_log_record_print(struct reftable_log_record *log,
+ uint32_t hash_id)
+{
+ char hex[GIT_SHA256_RAWSZ + 1] = { 0 };
+
+ switch (log->value_type) {
+ case REFTABLE_LOG_DELETION:
+ printf("log{%s(%" PRIu64 ") delete", log->refname,
+ log->update_index);
+ break;
+ case REFTABLE_LOG_UPDATE:
+ printf("log{%s(%" PRIu64 ") %s <%s> %" PRIu64 " %04d\n",
+ log->refname, log->update_index, log->update.name,
+ log->update.email, log->update.time,
+ log->update.tz_offset);
+ hex_format(hex, log->update.old_hash, hash_size(hash_id));
+ printf("%s => ", hex);
+ hex_format(hex, log->update.new_hash, hash_size(hash_id));
+ printf("%s\n\n%s\n}\n", hex, log->update.message);
+ break;
+ }
+}
+
+static void reftable_log_record_key(const void *r, struct strbuf *dest)
+{
+ const struct reftable_log_record *rec =
+ (const struct reftable_log_record *)r;
+ int len = strlen(rec->refname);
+ uint8_t i64[8];
+ uint64_t ts = 0;
+ strbuf_reset(dest);
+ strbuf_add(dest, (uint8_t *)rec->refname, len + 1);
+
+ ts = (~ts) - rec->update_index;
+ put_be64(&i64[0], ts);
+ strbuf_add(dest, i64, sizeof(i64));
+}
+
+static void reftable_log_record_copy_from(void *rec, const void *src_rec,
+ int hash_size)
+{
+ struct reftable_log_record *dst = rec;
+ const struct reftable_log_record *src =
+ (const struct reftable_log_record *)src_rec;
+
+ reftable_log_record_release(dst);
+ *dst = *src;
+ if (dst->refname) {
+ dst->refname = xstrdup(dst->refname);
+ }
+ switch (dst->value_type) {
+ case REFTABLE_LOG_DELETION:
+ break;
+ case REFTABLE_LOG_UPDATE:
+ if (dst->update.email) {
+ dst->update.email = xstrdup(dst->update.email);
+ }
+ if (dst->update.name) {
+ dst->update.name = xstrdup(dst->update.name);
+ }
+ if (dst->update.message) {
+ dst->update.message = xstrdup(dst->update.message);
+ }
+
+ if (dst->update.new_hash) {
+ dst->update.new_hash = reftable_malloc(hash_size);
+ memcpy(dst->update.new_hash, src->update.new_hash,
+ hash_size);
+ }
+ if (dst->update.old_hash) {
+ dst->update.old_hash = reftable_malloc(hash_size);
+ memcpy(dst->update.old_hash, src->update.old_hash,
+ hash_size);
+ }
+ break;
+ }
+}
+
+static void reftable_log_record_release_void(void *rec)
+{
+ struct reftable_log_record *r = rec;
+ reftable_log_record_release(r);
+}
+
+void reftable_log_record_release(struct reftable_log_record *r)
+{
+ reftable_free(r->refname);
+ switch (r->value_type) {
+ case REFTABLE_LOG_DELETION:
+ break;
+ case REFTABLE_LOG_UPDATE:
+ reftable_free(r->update.new_hash);
+ reftable_free(r->update.old_hash);
+ reftable_free(r->update.name);
+ reftable_free(r->update.email);
+ reftable_free(r->update.message);
+ break;
+ }
+ memset(r, 0, sizeof(struct reftable_log_record));
+}
+
+static uint8_t reftable_log_record_val_type(const void *rec)
+{
+ const struct reftable_log_record *log =
+ (const struct reftable_log_record *)rec;
+
+ return reftable_log_record_is_deletion(log) ? 0 : 1;
+}
+
+static uint8_t zero[GIT_SHA256_RAWSZ] = { 0 };
+
+static int reftable_log_record_encode(const void *rec, struct string_view s,
+ int hash_size)
+{
+ const struct reftable_log_record *r = rec;
+ struct string_view start = s;
+ int n = 0;
+ uint8_t *oldh = NULL;
+ uint8_t *newh = NULL;
+ if (reftable_log_record_is_deletion(r))
+ return 0;
+
+ oldh = r->update.old_hash;
+ newh = r->update.new_hash;
+ if (!oldh) {
+ oldh = zero;
+ }
+ if (!newh) {
+ newh = zero;
+ }
+
+ if (s.len < 2 * hash_size)
+ return -1;
+
+ memcpy(s.buf, oldh, hash_size);
+ memcpy(s.buf + hash_size, newh, hash_size);
+ string_view_consume(&s, 2 * hash_size);
+
+ n = encode_string(r->update.name ? r->update.name : "", s);
+ if (n < 0)
+ return -1;
+ string_view_consume(&s, n);
+
+ n = encode_string(r->update.email ? r->update.email : "", s);
+ if (n < 0)
+ return -1;
+ string_view_consume(&s, n);
+
+ n = put_var_int(&s, r->update.time);
+ if (n < 0)
+ return -1;
+ string_view_consume(&s, n);
+
+ if (s.len < 2)
+ return -1;
+
+ put_be16(s.buf, r->update.tz_offset);
+ string_view_consume(&s, 2);
+
+ n = encode_string(r->update.message ? r->update.message : "", s);
+ if (n < 0)
+ return -1;
+ string_view_consume(&s, n);
+
+ return start.len - s.len;
+}
+
+static int reftable_log_record_decode(void *rec, struct strbuf key,
+ uint8_t val_type, struct string_view in,
+ int hash_size)
+{
+ struct string_view start = in;
+ struct reftable_log_record *r = rec;
+ uint64_t max = 0;
+ uint64_t ts = 0;
+ struct strbuf dest = STRBUF_INIT;
+ int n;
+
+ if (key.len <= 9 || key.buf[key.len - 9] != 0)
+ return REFTABLE_FORMAT_ERROR;
+
+ r->refname = reftable_realloc(r->refname, key.len - 8);
+ memcpy(r->refname, key.buf, key.len - 8);
+ ts = get_be64(key.buf + key.len - 8);
+
+ r->update_index = (~max) - ts;
+
+ if (val_type != r->value_type) {
+ switch (r->value_type) {
+ case REFTABLE_LOG_UPDATE:
+ FREE_AND_NULL(r->update.old_hash);
+ FREE_AND_NULL(r->update.new_hash);
+ FREE_AND_NULL(r->update.message);
+ FREE_AND_NULL(r->update.email);
+ FREE_AND_NULL(r->update.name);
+ break;
+ case REFTABLE_LOG_DELETION:
+ break;
+ }
+ }
+
+ r->value_type = val_type;
+ if (val_type == REFTABLE_LOG_DELETION)
+ return 0;
+
+ if (in.len < 2 * hash_size)
+ return REFTABLE_FORMAT_ERROR;
+
+ r->update.old_hash = reftable_realloc(r->update.old_hash, hash_size);
+ r->update.new_hash = reftable_realloc(r->update.new_hash, hash_size);
+
+ memcpy(r->update.old_hash, in.buf, hash_size);
+ memcpy(r->update.new_hash, in.buf + hash_size, hash_size);
+
+ string_view_consume(&in, 2 * hash_size);
+
+ n = decode_string(&dest, in);
+ if (n < 0)
+ goto done;
+ string_view_consume(&in, n);
+
+ r->update.name = reftable_realloc(r->update.name, dest.len + 1);
+ memcpy(r->update.name, dest.buf, dest.len);
+ r->update.name[dest.len] = 0;
+
+ strbuf_reset(&dest);
+ n = decode_string(&dest, in);
+ if (n < 0)
+ goto done;
+ string_view_consume(&in, n);
+
+ r->update.email = reftable_realloc(r->update.email, dest.len + 1);
+ memcpy(r->update.email, dest.buf, dest.len);
+ r->update.email[dest.len] = 0;
+
+ ts = 0;
+ n = get_var_int(&ts, &in);
+ if (n < 0)
+ goto done;
+ string_view_consume(&in, n);
+ r->update.time = ts;
+ if (in.len < 2)
+ goto done;
+
+ r->update.tz_offset = get_be16(in.buf);
+ string_view_consume(&in, 2);
+
+ strbuf_reset(&dest);
+ n = decode_string(&dest, in);
+ if (n < 0)
+ goto done;
+ string_view_consume(&in, n);
+
+ r->update.message = reftable_realloc(r->update.message, dest.len + 1);
+ memcpy(r->update.message, dest.buf, dest.len);
+ r->update.message[dest.len] = 0;
+
+ strbuf_release(&dest);
+ return start.len - in.len;
+
+done:
+ strbuf_release(&dest);
+ return REFTABLE_FORMAT_ERROR;
+}
+
+static int null_streq(char *a, char *b)
+{
+ char *empty = "";
+ if (!a)
+ a = empty;
+
+ if (!b)
+ b = empty;
+
+ return 0 == strcmp(a, b);
+}
+
+static int zero_hash_eq(uint8_t *a, uint8_t *b, int sz)
+{
+ if (!a)
+ a = zero;
+
+ if (!b)
+ b = zero;
+
+ return !memcmp(a, b, sz);
+}
+
+int reftable_log_record_equal(struct reftable_log_record *a,
+ struct reftable_log_record *b, int hash_size)
+{
+ if (!(null_streq(a->refname, b->refname) &&
+ a->update_index == b->update_index &&
+ a->value_type == b->value_type))
+ return 0;
+
+ switch (a->value_type) {
+ case REFTABLE_LOG_DELETION:
+ return 1;
+ case REFTABLE_LOG_UPDATE:
+ return null_streq(a->update.name, b->update.name) &&
+ a->update.time == b->update.time &&
+ a->update.tz_offset == b->update.tz_offset &&
+ null_streq(a->update.email, b->update.email) &&
+ null_streq(a->update.message, b->update.message) &&
+ zero_hash_eq(a->update.old_hash, b->update.old_hash,
+ hash_size) &&
+ zero_hash_eq(a->update.new_hash, b->update.new_hash,
+ hash_size);
+ }
+
+ abort();
+}
+
+static int reftable_log_record_is_deletion_void(const void *p)
+{
+ return reftable_log_record_is_deletion(
+ (const struct reftable_log_record *)p);
+}
+
+static struct reftable_record_vtable reftable_log_record_vtable = {
+ .key = &reftable_log_record_key,
+ .type = BLOCK_TYPE_LOG,
+ .copy_from = &reftable_log_record_copy_from,
+ .val_type = &reftable_log_record_val_type,
+ .encode = &reftable_log_record_encode,
+ .decode = &reftable_log_record_decode,
+ .release = &reftable_log_record_release_void,
+ .is_deletion = &reftable_log_record_is_deletion_void,
+};
+
+struct reftable_record reftable_new_record(uint8_t typ)
+{
+ struct reftable_record rec = { NULL };
+ switch (typ) {
+ case BLOCK_TYPE_REF: {
+ struct reftable_ref_record *r =
+ reftable_calloc(sizeof(struct reftable_ref_record));
+ reftable_record_from_ref(&rec, r);
+ return rec;
+ }
+
+ case BLOCK_TYPE_OBJ: {
+ struct reftable_obj_record *r =
+ reftable_calloc(sizeof(struct reftable_obj_record));
+ reftable_record_from_obj(&rec, r);
+ return rec;
+ }
+ case BLOCK_TYPE_LOG: {
+ struct reftable_log_record *r =
+ reftable_calloc(sizeof(struct reftable_log_record));
+ reftable_record_from_log(&rec, r);
+ return rec;
+ }
+ case BLOCK_TYPE_INDEX: {
+ struct reftable_index_record empty = { .last_key =
+ STRBUF_INIT };
+ struct reftable_index_record *r =
+ reftable_calloc(sizeof(struct reftable_index_record));
+ *r = empty;
+ reftable_record_from_index(&rec, r);
+ return rec;
+ }
+ }
+ abort();
+ return rec;
+}
+
+/* clear out the record, yielding the reftable_record data that was
+ * encapsulated. */
+static void *reftable_record_yield(struct reftable_record *rec)
+{
+ void *p = rec->data;
+ rec->data = NULL;
+ return p;
+}
+
+void reftable_record_destroy(struct reftable_record *rec)
+{
+ reftable_record_release(rec);
+ reftable_free(reftable_record_yield(rec));
+}
+
+static void reftable_index_record_key(const void *r, struct strbuf *dest)
+{
+ const struct reftable_index_record *rec = r;
+ strbuf_reset(dest);
+ strbuf_addbuf(dest, &rec->last_key);
+}
+
+static void reftable_index_record_copy_from(void *rec, const void *src_rec,
+ int hash_size)
+{
+ struct reftable_index_record *dst = rec;
+ const struct reftable_index_record *src = src_rec;
+
+ strbuf_reset(&dst->last_key);
+ strbuf_addbuf(&dst->last_key, &src->last_key);
+ dst->offset = src->offset;
+}
+
+static void reftable_index_record_release(void *rec)
+{
+ struct reftable_index_record *idx = rec;
+ strbuf_release(&idx->last_key);
+}
+
+static uint8_t reftable_index_record_val_type(const void *rec)
+{
+ return 0;
+}
+
+static int reftable_index_record_encode(const void *rec, struct string_view out,
+ int hash_size)
+{
+ const struct reftable_index_record *r =
+ (const struct reftable_index_record *)rec;
+ struct string_view start = out;
+
+ int n = put_var_int(&out, r->offset);
+ if (n < 0)
+ return n;
+
+ string_view_consume(&out, n);
+
+ return start.len - out.len;
+}
+
+static int reftable_index_record_decode(void *rec, struct strbuf key,
+ uint8_t val_type, struct string_view in,
+ int hash_size)
+{
+ struct string_view start = in;
+ struct reftable_index_record *r = rec;
+ int n = 0;
+
+ strbuf_reset(&r->last_key);
+ strbuf_addbuf(&r->last_key, &key);
+
+ n = get_var_int(&r->offset, &in);
+ if (n < 0)
+ return n;
+
+ string_view_consume(&in, n);
+ return start.len - in.len;
+}
+
+static struct reftable_record_vtable reftable_index_record_vtable = {
+ .key = &reftable_index_record_key,
+ .type = BLOCK_TYPE_INDEX,
+ .copy_from = &reftable_index_record_copy_from,
+ .val_type = &reftable_index_record_val_type,
+ .encode = &reftable_index_record_encode,
+ .decode = &reftable_index_record_decode,
+ .release = &reftable_index_record_release,
+ .is_deletion = &not_a_deletion,
+};
+
+void reftable_record_key(struct reftable_record *rec, struct strbuf *dest)
+{
+ rec->ops->key(rec->data, dest);
+}
+
+uint8_t reftable_record_type(struct reftable_record *rec)
+{
+ return rec->ops->type;
+}
+
+int reftable_record_encode(struct reftable_record *rec, struct string_view dest,
+ int hash_size)
+{
+ return rec->ops->encode(rec->data, dest, hash_size);
+}
+
+void reftable_record_copy_from(struct reftable_record *rec,
+ struct reftable_record *src, int hash_size)
+{
+ assert(src->ops->type == rec->ops->type);
+
+ rec->ops->copy_from(rec->data, src->data, hash_size);
+}
+
+uint8_t reftable_record_val_type(struct reftable_record *rec)
+{
+ return rec->ops->val_type(rec->data);
+}
+
+int reftable_record_decode(struct reftable_record *rec, struct strbuf key,
+ uint8_t extra, struct string_view src, int hash_size)
+{
+ return rec->ops->decode(rec->data, key, extra, src, hash_size);
+}
+
+void reftable_record_release(struct reftable_record *rec)
+{
+ rec->ops->release(rec->data);
+}
+
+int reftable_record_is_deletion(struct reftable_record *rec)
+{
+ return rec->ops->is_deletion(rec->data);
+}
+
+void reftable_record_from_ref(struct reftable_record *rec,
+ struct reftable_ref_record *ref_rec)
+{
+ assert(!rec->ops);
+ rec->data = ref_rec;
+ rec->ops = &reftable_ref_record_vtable;
+}
+
+void reftable_record_from_obj(struct reftable_record *rec,
+ struct reftable_obj_record *obj_rec)
+{
+ assert(!rec->ops);
+ rec->data = obj_rec;
+ rec->ops = &reftable_obj_record_vtable;
+}
+
+void reftable_record_from_index(struct reftable_record *rec,
+ struct reftable_index_record *index_rec)
+{
+ assert(!rec->ops);
+ rec->data = index_rec;
+ rec->ops = &reftable_index_record_vtable;
+}
+
+void reftable_record_from_log(struct reftable_record *rec,
+ struct reftable_log_record *log_rec)
+{
+ assert(!rec->ops);
+ rec->data = log_rec;
+ rec->ops = &reftable_log_record_vtable;
+}
+
+struct reftable_ref_record *reftable_record_as_ref(struct reftable_record *rec)
+{
+ assert(reftable_record_type(rec) == BLOCK_TYPE_REF);
+ return rec->data;
+}
+
+struct reftable_log_record *reftable_record_as_log(struct reftable_record *rec)
+{
+ assert(reftable_record_type(rec) == BLOCK_TYPE_LOG);
+ return rec->data;
+}
+
+static int hash_equal(uint8_t *a, uint8_t *b, int hash_size)
+{
+ if (a && b)
+ return !memcmp(a, b, hash_size);
+
+ return a == b;
+}
+
+int reftable_ref_record_equal(struct reftable_ref_record *a,
+ struct reftable_ref_record *b, int hash_size)
+{
+ assert(hash_size > 0);
+ if (!(0 == strcmp(a->refname, b->refname) &&
+ a->update_index == b->update_index &&
+ a->value_type == b->value_type))
+ return 0;
+
+ switch (a->value_type) {
+ case REFTABLE_REF_SYMREF:
+ return !strcmp(a->value.symref, b->value.symref);
+ case REFTABLE_REF_VAL2:
+ return hash_equal(a->value.val2.value, b->value.val2.value,
+ hash_size) &&
+ hash_equal(a->value.val2.target_value,
+ b->value.val2.target_value, hash_size);
+ case REFTABLE_REF_VAL1:
+ return hash_equal(a->value.val1, b->value.val1, hash_size);
+ case REFTABLE_REF_DELETION:
+ return 1;
+ default:
+ abort();
+ }
+}
+
+int reftable_ref_record_compare_name(const void *a, const void *b)
+{
+ return strcmp(((struct reftable_ref_record *)a)->refname,
+ ((struct reftable_ref_record *)b)->refname);
+}
+
+int reftable_ref_record_is_deletion(const struct reftable_ref_record *ref)
+{
+ return ref->value_type == REFTABLE_REF_DELETION;
+}
+
+int reftable_log_record_compare_key(const void *a, const void *b)
+{
+ const struct reftable_log_record *la = a;
+ const struct reftable_log_record *lb = b;
+
+ int cmp = strcmp(la->refname, lb->refname);
+ if (cmp)
+ return cmp;
+ if (la->update_index > lb->update_index)
+ return -1;
+ return (la->update_index < lb->update_index) ? 1 : 0;
+}
+
+int reftable_log_record_is_deletion(const struct reftable_log_record *log)
+{
+ return (log->value_type == REFTABLE_LOG_DELETION);
+}
+
+void string_view_consume(struct string_view *s, int n)
+{
+ s->buf += n;
+ s->len -= n;
+}
diff --git a/reftable/record.h b/reftable/record.h
new file mode 100644
index 0000000..498e8c5
--- /dev/null
+++ b/reftable/record.h
@@ -0,0 +1,139 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef RECORD_H
+#define RECORD_H
+
+#include "system.h"
+
+#include <stdint.h>
+
+#include "reftable-record.h"
+
+/*
+ * A substring of existing string data. This structure takes no responsibility
+ * for the lifetime of the data it points to.
+ */
+struct string_view {
+ uint8_t *buf;
+ size_t len;
+};
+
+/* Advance `s.buf` by `n`, and decrease length. */
+void string_view_consume(struct string_view *s, int n);
+
+/* utilities for de/encoding varints */
+
+int get_var_int(uint64_t *dest, struct string_view *in);
+int put_var_int(struct string_view *dest, uint64_t val);
+
+/* Methods for records. */
+struct reftable_record_vtable {
+ /* encode the key of to a uint8_t strbuf. */
+ void (*key)(const void *rec, struct strbuf *dest);
+
+ /* The record type of ('r' for ref). */
+ uint8_t type;
+
+ void (*copy_from)(void *dest, const void *src, int hash_size);
+
+ /* a value of [0..7], indicating record subvariants (eg. ref vs. symref
+ * vs ref deletion) */
+ uint8_t (*val_type)(const void *rec);
+
+ /* encodes rec into dest, returning how much space was used. */
+ int (*encode)(const void *rec, struct string_view dest, int hash_size);
+
+ /* decode data from `src` into the record. */
+ int (*decode)(void *rec, struct strbuf key, uint8_t extra,
+ struct string_view src, int hash_size);
+
+ /* deallocate and null the record. */
+ void (*release)(void *rec);
+
+ /* is this a tombstone? */
+ int (*is_deletion)(const void *rec);
+};
+
+/* record is a generic wrapper for different types of records. */
+struct reftable_record {
+ void *data;
+ struct reftable_record_vtable *ops;
+};
+
+/* returns true for recognized block types. Block start with the block type. */
+int reftable_is_block_type(uint8_t typ);
+
+/* creates a malloced record of the given type. Dispose with record_destroy */
+struct reftable_record reftable_new_record(uint8_t typ);
+
+/* Encode `key` into `dest`. Sets `is_restart` to indicate a restart. Returns
+ * number of bytes written. */
+int reftable_encode_key(int *is_restart, struct string_view dest,
+ struct strbuf prev_key, struct strbuf key,
+ uint8_t extra);
+
+/* Decode into `key` and `extra` from `in` */
+int reftable_decode_key(struct strbuf *key, uint8_t *extra,
+ struct strbuf last_key, struct string_view in);
+
+/* reftable_index_record are used internally to speed up lookups. */
+struct reftable_index_record {
+ uint64_t offset; /* Offset of block */
+ struct strbuf last_key; /* Last key of the block. */
+};
+
+/* reftable_obj_record stores an object ID => ref mapping. */
+struct reftable_obj_record {
+ uint8_t *hash_prefix; /* leading bytes of the object ID */
+ int hash_prefix_len; /* number of leading bytes. Constant
+ * across a single table. */
+ uint64_t *offsets; /* a vector of file offsets. */
+ int offset_len;
+};
+
+/* see struct record_vtable */
+
+void reftable_record_key(struct reftable_record *rec, struct strbuf *dest);
+uint8_t reftable_record_type(struct reftable_record *rec);
+void reftable_record_copy_from(struct reftable_record *rec,
+ struct reftable_record *src, int hash_size);
+uint8_t reftable_record_val_type(struct reftable_record *rec);
+int reftable_record_encode(struct reftable_record *rec, struct string_view dest,
+ int hash_size);
+int reftable_record_decode(struct reftable_record *rec, struct strbuf key,
+ uint8_t extra, struct string_view src,
+ int hash_size);
+int reftable_record_is_deletion(struct reftable_record *rec);
+
+/* zeroes out the embedded record */
+void reftable_record_release(struct reftable_record *rec);
+
+/* clear and deallocate embedded record, and zero `rec`. */
+void reftable_record_destroy(struct reftable_record *rec);
+
+/* initialize generic records from concrete records. The generic record should
+ * be zeroed out. */
+void reftable_record_from_obj(struct reftable_record *rec,
+ struct reftable_obj_record *objrec);
+void reftable_record_from_index(struct reftable_record *rec,
+ struct reftable_index_record *idxrec);
+void reftable_record_from_ref(struct reftable_record *rec,
+ struct reftable_ref_record *refrec);
+void reftable_record_from_log(struct reftable_record *rec,
+ struct reftable_log_record *logrec);
+struct reftable_ref_record *reftable_record_as_ref(struct reftable_record *ref);
+struct reftable_log_record *reftable_record_as_log(struct reftable_record *ref);
+
+/* for qsort. */
+int reftable_ref_record_compare_name(const void *a, const void *b);
+
+/* for qsort. */
+int reftable_log_record_compare_key(const void *a, const void *b);
+
+#endif
diff --git a/reftable/record_test.c b/reftable/record_test.c
new file mode 100644
index 0000000..bf5d072
--- /dev/null
+++ b/reftable/record_test.c
@@ -0,0 +1,407 @@
+/*
+ Copyright 2020 Google LLC
+
+ Use of this source code is governed by a BSD-style
+ license that can be found in the LICENSE file or at
+ https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "record.h"
+
+#include "system.h"
+#include "basics.h"
+#include "constants.h"
+#include "test_framework.h"
+#include "reftable-tests.h"
+
+static void test_copy(struct reftable_record *rec)
+{
+ struct reftable_record copy =
+ reftable_new_record(reftable_record_type(rec));
+ reftable_record_copy_from(&copy, rec, GIT_SHA1_RAWSZ);
+ /* do it twice to catch memory leaks */
+ reftable_record_copy_from(&copy, rec, GIT_SHA1_RAWSZ);
+ switch (reftable_record_type(&copy)) {
+ case BLOCK_TYPE_REF:
+ EXPECT(reftable_ref_record_equal(reftable_record_as_ref(&copy),
+ reftable_record_as_ref(rec),
+ GIT_SHA1_RAWSZ));
+ break;
+ case BLOCK_TYPE_LOG:
+ EXPECT(reftable_log_record_equal(reftable_record_as_log(&copy),
+ reftable_record_as_log(rec),
+ GIT_SHA1_RAWSZ));
+ break;
+ }
+ reftable_record_destroy(&copy);
+}
+
+static void test_varint_roundtrip(void)
+{
+ uint64_t inputs[] = { 0,
+ 1,
+ 27,
+ 127,
+ 128,
+ 257,
+ 4096,
+ ((uint64_t)1 << 63),
+ ((uint64_t)1 << 63) + ((uint64_t)1 << 63) - 1 };
+ int i = 0;
+ for (i = 0; i < ARRAY_SIZE(inputs); i++) {
+ uint8_t dest[10];
+
+ struct string_view out = {
+ .buf = dest,
+ .len = sizeof(dest),
+ };
+ uint64_t in = inputs[i];
+ int n = put_var_int(&out, in);
+ uint64_t got = 0;
+
+ EXPECT(n > 0);
+ out.len = n;
+ n = get_var_int(&got, &out);
+ EXPECT(n > 0);
+
+ EXPECT(got == in);
+ }
+}
+
+static void test_common_prefix(void)
+{
+ struct {
+ const char *a, *b;
+ int want;
+ } cases[] = {
+ { "abc", "ab", 2 },
+ { "", "abc", 0 },
+ { "abc", "abd", 2 },
+ { "abc", "pqr", 0 },
+ };
+
+ int i = 0;
+ for (i = 0; i < ARRAY_SIZE(cases); i++) {
+ struct strbuf a = STRBUF_INIT;
+ struct strbuf b = STRBUF_INIT;
+ strbuf_addstr(&a, cases[i].a);
+ strbuf_addstr(&b, cases[i].b);
+ EXPECT(common_prefix_size(&a, &b) == cases[i].want);
+
+ strbuf_release(&a);
+ strbuf_release(&b);
+ }
+}
+
+static void set_hash(uint8_t *h, int j)
+{
+ int i = 0;
+ for (i = 0; i < hash_size(GIT_SHA1_FORMAT_ID); i++) {
+ h[i] = (j >> i) & 0xff;
+ }
+}
+
+static void test_reftable_ref_record_roundtrip(void)
+{
+ int i = 0;
+
+ for (i = REFTABLE_REF_DELETION; i < REFTABLE_NR_REF_VALUETYPES; i++) {
+ struct reftable_ref_record in = { NULL };
+ struct reftable_ref_record out = { NULL };
+ struct reftable_record rec_out = { NULL };
+ struct strbuf key = STRBUF_INIT;
+ struct reftable_record rec = { NULL };
+ uint8_t buffer[1024] = { 0 };
+ struct string_view dest = {
+ .buf = buffer,
+ .len = sizeof(buffer),
+ };
+
+ int n, m;
+
+ in.value_type = i;
+ switch (i) {
+ case REFTABLE_REF_DELETION:
+ break;
+ case REFTABLE_REF_VAL1:
+ in.value.val1 = reftable_malloc(GIT_SHA1_RAWSZ);
+ set_hash(in.value.val1, 1);
+ break;
+ case REFTABLE_REF_VAL2:
+ in.value.val2.value = reftable_malloc(GIT_SHA1_RAWSZ);
+ set_hash(in.value.val2.value, 1);
+ in.value.val2.target_value =
+ reftable_malloc(GIT_SHA1_RAWSZ);
+ set_hash(in.value.val2.target_value, 2);
+ break;
+ case REFTABLE_REF_SYMREF:
+ in.value.symref = xstrdup("target");
+ break;
+ }
+ in.refname = xstrdup("refs/heads/master");
+
+ reftable_record_from_ref(&rec, &in);
+ test_copy(&rec);
+
+ EXPECT(reftable_record_val_type(&rec) == i);
+
+ reftable_record_key(&rec, &key);
+ n = reftable_record_encode(&rec, dest, GIT_SHA1_RAWSZ);
+ EXPECT(n > 0);
+
+ /* decode into a non-zero reftable_record to test for leaks. */
+
+ reftable_record_from_ref(&rec_out, &out);
+ m = reftable_record_decode(&rec_out, key, i, dest,
+ GIT_SHA1_RAWSZ);
+ EXPECT(n == m);
+
+ EXPECT(reftable_ref_record_equal(&in, &out, GIT_SHA1_RAWSZ));
+ reftable_record_release(&rec_out);
+
+ strbuf_release(&key);
+ reftable_ref_record_release(&in);
+ }
+}
+
+static void test_reftable_log_record_equal(void)
+{
+ struct reftable_log_record in[2] = {
+ {
+ .refname = xstrdup("refs/heads/master"),
+ .update_index = 42,
+ },
+ {
+ .refname = xstrdup("refs/heads/master"),
+ .update_index = 22,
+ }
+ };
+
+ EXPECT(!reftable_log_record_equal(&in[0], &in[1], GIT_SHA1_RAWSZ));
+ in[1].update_index = in[0].update_index;
+ EXPECT(reftable_log_record_equal(&in[0], &in[1], GIT_SHA1_RAWSZ));
+ reftable_log_record_release(&in[0]);
+ reftable_log_record_release(&in[1]);
+}
+
+static void test_reftable_log_record_roundtrip(void)
+{
+ struct reftable_log_record in[2] = {
+ {
+ .refname = xstrdup("refs/heads/master"),
+ .update_index = 42,
+ .value_type = REFTABLE_LOG_UPDATE,
+ .update = {
+ .old_hash = reftable_malloc(GIT_SHA1_RAWSZ),
+ .new_hash = reftable_malloc(GIT_SHA1_RAWSZ),
+ .name = xstrdup("han-wen"),
+ .email = xstrdup("hanwen@google.com"),
+ .message = xstrdup("test"),
+ .time = 1577123507,
+ .tz_offset = 100,
+ }
+ },
+ {
+ .refname = xstrdup("refs/heads/master"),
+ .update_index = 22,
+ .value_type = REFTABLE_LOG_DELETION,
+ }
+ };
+ set_test_hash(in[0].update.new_hash, 1);
+ set_test_hash(in[0].update.old_hash, 2);
+ for (int i = 0; i < ARRAY_SIZE(in); i++) {
+ struct reftable_record rec = { NULL };
+ struct strbuf key = STRBUF_INIT;
+ uint8_t buffer[1024] = { 0 };
+ struct string_view dest = {
+ .buf = buffer,
+ .len = sizeof(buffer),
+ };
+ /* populate out, to check for leaks. */
+ struct reftable_log_record out = {
+ .refname = xstrdup("old name"),
+ .value_type = REFTABLE_LOG_UPDATE,
+ .update = {
+ .new_hash = reftable_calloc(GIT_SHA1_RAWSZ),
+ .old_hash = reftable_calloc(GIT_SHA1_RAWSZ),
+ .name = xstrdup("old name"),
+ .email = xstrdup("old@email"),
+ .message = xstrdup("old message"),
+ },
+ };
+ struct reftable_record rec_out = { NULL };
+ int n, m, valtype;
+
+ reftable_record_from_log(&rec, &in[i]);
+
+ test_copy(&rec);
+
+ reftable_record_key(&rec, &key);
+
+ n = reftable_record_encode(&rec, dest, GIT_SHA1_RAWSZ);
+ EXPECT(n >= 0);
+ reftable_record_from_log(&rec_out, &out);
+ valtype = reftable_record_val_type(&rec);
+ m = reftable_record_decode(&rec_out, key, valtype, dest,
+ GIT_SHA1_RAWSZ);
+ EXPECT(n == m);
+
+ EXPECT(reftable_log_record_equal(&in[i], &out, GIT_SHA1_RAWSZ));
+ reftable_log_record_release(&in[i]);
+ strbuf_release(&key);
+ reftable_record_release(&rec_out);
+ }
+}
+
+static void test_u24_roundtrip(void)
+{
+ uint32_t in = 0x112233;
+ uint8_t dest[3];
+ uint32_t out;
+ put_be24(dest, in);
+ out = get_be24(dest);
+ EXPECT(in == out);
+}
+
+static void test_key_roundtrip(void)
+{
+ uint8_t buffer[1024] = { 0 };
+ struct string_view dest = {
+ .buf = buffer,
+ .len = sizeof(buffer),
+ };
+ struct strbuf last_key = STRBUF_INIT;
+ struct strbuf key = STRBUF_INIT;
+ struct strbuf roundtrip = STRBUF_INIT;
+ int restart;
+ uint8_t extra;
+ int n, m;
+ uint8_t rt_extra;
+
+ strbuf_addstr(&last_key, "refs/heads/master");
+ strbuf_addstr(&key, "refs/tags/bla");
+ extra = 6;
+ n = reftable_encode_key(&restart, dest, last_key, key, extra);
+ EXPECT(!restart);
+ EXPECT(n > 0);
+
+ m = reftable_decode_key(&roundtrip, &rt_extra, last_key, dest);
+ EXPECT(n == m);
+ EXPECT(0 == strbuf_cmp(&key, &roundtrip));
+ EXPECT(rt_extra == extra);
+
+ strbuf_release(&last_key);
+ strbuf_release(&key);
+ strbuf_release(&roundtrip);
+}
+
+static void test_reftable_obj_record_roundtrip(void)
+{
+ uint8_t testHash1[GIT_SHA1_RAWSZ] = { 1, 2, 3, 4, 0 };
+ uint64_t till9[] = { 1, 2, 3, 4, 500, 600, 700, 800, 9000 };
+ struct reftable_obj_record recs[3] = { {
+ .hash_prefix = testHash1,
+ .hash_prefix_len = 5,
+ .offsets = till9,
+ .offset_len = 3,
+ },
+ {
+ .hash_prefix = testHash1,
+ .hash_prefix_len = 5,
+ .offsets = till9,
+ .offset_len = 9,
+ },
+ {
+ .hash_prefix = testHash1,
+ .hash_prefix_len = 5,
+ } };
+ int i = 0;
+ for (i = 0; i < ARRAY_SIZE(recs); i++) {
+ struct reftable_obj_record in = recs[i];
+ uint8_t buffer[1024] = { 0 };
+ struct string_view dest = {
+ .buf = buffer,
+ .len = sizeof(buffer),
+ };
+ struct reftable_record rec = { NULL };
+ struct strbuf key = STRBUF_INIT;
+ struct reftable_obj_record out = { NULL };
+ struct reftable_record rec_out = { NULL };
+ int n, m;
+ uint8_t extra;
+
+ reftable_record_from_obj(&rec, &in);
+ test_copy(&rec);
+ reftable_record_key(&rec, &key);
+ n = reftable_record_encode(&rec, dest, GIT_SHA1_RAWSZ);
+ EXPECT(n > 0);
+ extra = reftable_record_val_type(&rec);
+ reftable_record_from_obj(&rec_out, &out);
+ m = reftable_record_decode(&rec_out, key, extra, dest,
+ GIT_SHA1_RAWSZ);
+ EXPECT(n == m);
+
+ EXPECT(in.hash_prefix_len == out.hash_prefix_len);
+ EXPECT(in.offset_len == out.offset_len);
+
+ EXPECT(!memcmp(in.hash_prefix, out.hash_prefix,
+ in.hash_prefix_len));
+ EXPECT(0 == memcmp(in.offsets, out.offsets,
+ sizeof(uint64_t) * in.offset_len));
+ strbuf_release(&key);
+ reftable_record_release(&rec_out);
+ }
+}
+
+static void test_reftable_index_record_roundtrip(void)
+{
+ struct reftable_index_record in = {
+ .offset = 42,
+ .last_key = STRBUF_INIT,
+ };
+ uint8_t buffer[1024] = { 0 };
+ struct string_view dest = {
+ .buf = buffer,
+ .len = sizeof(buffer),
+ };
+ struct strbuf key = STRBUF_INIT;
+ struct reftable_record rec = { NULL };
+ struct reftable_index_record out = { .last_key = STRBUF_INIT };
+ struct reftable_record out_rec = { NULL };
+ int n, m;
+ uint8_t extra;
+
+ strbuf_addstr(&in.last_key, "refs/heads/master");
+ reftable_record_from_index(&rec, &in);
+ reftable_record_key(&rec, &key);
+ test_copy(&rec);
+
+ EXPECT(0 == strbuf_cmp(&key, &in.last_key));
+ n = reftable_record_encode(&rec, dest, GIT_SHA1_RAWSZ);
+ EXPECT(n > 0);
+
+ extra = reftable_record_val_type(&rec);
+ reftable_record_from_index(&out_rec, &out);
+ m = reftable_record_decode(&out_rec, key, extra, dest, GIT_SHA1_RAWSZ);
+ EXPECT(m == n);
+
+ EXPECT(in.offset == out.offset);
+
+ reftable_record_release(&out_rec);
+ strbuf_release(&key);
+ strbuf_release(&in.last_key);
+}
+
+int record_test_main(int argc, const char *argv[])
+{
+ RUN_TEST(test_reftable_log_record_equal);
+ RUN_TEST(test_reftable_log_record_roundtrip);
+ RUN_TEST(test_reftable_ref_record_roundtrip);
+ RUN_TEST(test_varint_roundtrip);
+ RUN_TEST(test_key_roundtrip);
+ RUN_TEST(test_common_prefix);
+ RUN_TEST(test_reftable_obj_record_roundtrip);
+ RUN_TEST(test_reftable_index_record_roundtrip);
+ RUN_TEST(test_u24_roundtrip);
+ return 0;
+}
diff --git a/reftable/refname.c b/reftable/refname.c
new file mode 100644
index 0000000..9573496
--- /dev/null
+++ b/reftable/refname.c
@@ -0,0 +1,209 @@
+/*
+ Copyright 2020 Google LLC
+
+ Use of this source code is governed by a BSD-style
+ license that can be found in the LICENSE file or at
+ https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "system.h"
+#include "reftable-error.h"
+#include "basics.h"
+#include "refname.h"
+#include "reftable-iterator.h"
+
+struct find_arg {
+ char **names;
+ const char *want;
+};
+
+static int find_name(size_t k, void *arg)
+{
+ struct find_arg *f_arg = arg;
+ return strcmp(f_arg->names[k], f_arg->want) >= 0;
+}
+
+static int modification_has_ref(struct modification *mod, const char *name)
+{
+ struct reftable_ref_record ref = { NULL };
+ int err = 0;
+
+ if (mod->add_len > 0) {
+ struct find_arg arg = {
+ .names = mod->add,
+ .want = name,
+ };
+ int idx = binsearch(mod->add_len, find_name, &arg);
+ if (idx < mod->add_len && !strcmp(mod->add[idx], name)) {
+ return 0;
+ }
+ }
+
+ if (mod->del_len > 0) {
+ struct find_arg arg = {
+ .names = mod->del,
+ .want = name,
+ };
+ int idx = binsearch(mod->del_len, find_name, &arg);
+ if (idx < mod->del_len && !strcmp(mod->del[idx], name)) {
+ return 1;
+ }
+ }
+
+ err = reftable_table_read_ref(&mod->tab, name, &ref);
+ reftable_ref_record_release(&ref);
+ return err;
+}
+
+static void modification_release(struct modification *mod)
+{
+ /* don't delete the strings themselves; they're owned by ref records.
+ */
+ FREE_AND_NULL(mod->add);
+ FREE_AND_NULL(mod->del);
+ mod->add_len = 0;
+ mod->del_len = 0;
+}
+
+static int modification_has_ref_with_prefix(struct modification *mod,
+ const char *prefix)
+{
+ struct reftable_iterator it = { NULL };
+ struct reftable_ref_record ref = { NULL };
+ int err = 0;
+
+ if (mod->add_len > 0) {
+ struct find_arg arg = {
+ .names = mod->add,
+ .want = prefix,
+ };
+ int idx = binsearch(mod->add_len, find_name, &arg);
+ if (idx < mod->add_len &&
+ !strncmp(prefix, mod->add[idx], strlen(prefix)))
+ goto done;
+ }
+ err = reftable_table_seek_ref(&mod->tab, &it, prefix);
+ if (err)
+ goto done;
+
+ while (1) {
+ err = reftable_iterator_next_ref(&it, &ref);
+ if (err)
+ goto done;
+
+ if (mod->del_len > 0) {
+ struct find_arg arg = {
+ .names = mod->del,
+ .want = ref.refname,
+ };
+ int idx = binsearch(mod->del_len, find_name, &arg);
+ if (idx < mod->del_len &&
+ !strcmp(ref.refname, mod->del[idx])) {
+ continue;
+ }
+ }
+
+ if (strncmp(ref.refname, prefix, strlen(prefix))) {
+ err = 1;
+ goto done;
+ }
+ err = 0;
+ goto done;
+ }
+
+done:
+ reftable_ref_record_release(&ref);
+ reftable_iterator_destroy(&it);
+ return err;
+}
+
+static int validate_refname(const char *name)
+{
+ while (1) {
+ char *next = strchr(name, '/');
+ if (!*name) {
+ return REFTABLE_REFNAME_ERROR;
+ }
+ if (!next) {
+ return 0;
+ }
+ if (next - name == 0 || (next - name == 1 && *name == '.') ||
+ (next - name == 2 && name[0] == '.' && name[1] == '.'))
+ return REFTABLE_REFNAME_ERROR;
+ name = next + 1;
+ }
+ return 0;
+}
+
+int validate_ref_record_addition(struct reftable_table tab,
+ struct reftable_ref_record *recs, size_t sz)
+{
+ struct modification mod = {
+ .tab = tab,
+ .add = reftable_calloc(sizeof(char *) * sz),
+ .del = reftable_calloc(sizeof(char *) * sz),
+ };
+ int i = 0;
+ int err = 0;
+ for (; i < sz; i++) {
+ if (reftable_ref_record_is_deletion(&recs[i])) {
+ mod.del[mod.del_len++] = recs[i].refname;
+ } else {
+ mod.add[mod.add_len++] = recs[i].refname;
+ }
+ }
+
+ err = modification_validate(&mod);
+ modification_release(&mod);
+ return err;
+}
+
+static void strbuf_trim_component(struct strbuf *sl)
+{
+ while (sl->len > 0) {
+ int is_slash = (sl->buf[sl->len - 1] == '/');
+ strbuf_setlen(sl, sl->len - 1);
+ if (is_slash)
+ break;
+ }
+}
+
+int modification_validate(struct modification *mod)
+{
+ struct strbuf slashed = STRBUF_INIT;
+ int err = 0;
+ int i = 0;
+ for (; i < mod->add_len; i++) {
+ err = validate_refname(mod->add[i]);
+ if (err)
+ goto done;
+ strbuf_reset(&slashed);
+ strbuf_addstr(&slashed, mod->add[i]);
+ strbuf_addstr(&slashed, "/");
+
+ err = modification_has_ref_with_prefix(mod, slashed.buf);
+ if (err == 0) {
+ err = REFTABLE_NAME_CONFLICT;
+ goto done;
+ }
+ if (err < 0)
+ goto done;
+
+ strbuf_reset(&slashed);
+ strbuf_addstr(&slashed, mod->add[i]);
+ while (slashed.len) {
+ strbuf_trim_component(&slashed);
+ err = modification_has_ref(mod, slashed.buf);
+ if (err == 0) {
+ err = REFTABLE_NAME_CONFLICT;
+ goto done;
+ }
+ if (err < 0)
+ goto done;
+ }
+ }
+ err = 0;
+done:
+ strbuf_release(&slashed);
+ return err;
+}
diff --git a/reftable/refname.h b/reftable/refname.h
new file mode 100644
index 0000000..a24b40f
--- /dev/null
+++ b/reftable/refname.h
@@ -0,0 +1,29 @@
+/*
+ Copyright 2020 Google LLC
+
+ Use of this source code is governed by a BSD-style
+ license that can be found in the LICENSE file or at
+ https://developers.google.com/open-source/licenses/bsd
+*/
+#ifndef REFNAME_H
+#define REFNAME_H
+
+#include "reftable-record.h"
+#include "reftable-generic.h"
+
+struct modification {
+ struct reftable_table tab;
+
+ char **add;
+ size_t add_len;
+
+ char **del;
+ size_t del_len;
+};
+
+int validate_ref_record_addition(struct reftable_table tab,
+ struct reftable_ref_record *recs, size_t sz);
+
+int modification_validate(struct modification *mod);
+
+#endif
diff --git a/reftable/refname_test.c b/reftable/refname_test.c
new file mode 100644
index 0000000..8645cd9
--- /dev/null
+++ b/reftable/refname_test.c
@@ -0,0 +1,102 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "basics.h"
+#include "block.h"
+#include "blocksource.h"
+#include "constants.h"
+#include "reader.h"
+#include "record.h"
+#include "refname.h"
+#include "reftable-error.h"
+#include "reftable-writer.h"
+#include "system.h"
+
+#include "test_framework.h"
+#include "reftable-tests.h"
+
+struct testcase {
+ char *add;
+ char *del;
+ int error_code;
+};
+
+static void test_conflict(void)
+{
+ struct reftable_write_options opts = { 0 };
+ struct strbuf buf = STRBUF_INIT;
+ struct reftable_writer *w =
+ reftable_new_writer(&strbuf_add_void, &buf, &opts);
+ struct reftable_ref_record rec = {
+ .refname = "a/b",
+ .value_type = REFTABLE_REF_SYMREF,
+ .value.symref = "destination", /* make sure it's not a symref.
+ */
+ .update_index = 1,
+ };
+ int err;
+ int i;
+ struct reftable_block_source source = { NULL };
+ struct reftable_reader *rd = NULL;
+ struct reftable_table tab = { NULL };
+ struct testcase cases[] = {
+ { "a/b/c", NULL, REFTABLE_NAME_CONFLICT },
+ { "b", NULL, 0 },
+ { "a", NULL, REFTABLE_NAME_CONFLICT },
+ { "a", "a/b", 0 },
+
+ { "p/", NULL, REFTABLE_REFNAME_ERROR },
+ { "p//q", NULL, REFTABLE_REFNAME_ERROR },
+ { "p/./q", NULL, REFTABLE_REFNAME_ERROR },
+ { "p/../q", NULL, REFTABLE_REFNAME_ERROR },
+
+ { "a/b/c", "a/b", 0 },
+ { NULL, "a//b", 0 },
+ };
+ reftable_writer_set_limits(w, 1, 1);
+
+ err = reftable_writer_add_ref(w, &rec);
+ EXPECT_ERR(err);
+
+ err = reftable_writer_close(w);
+ EXPECT_ERR(err);
+ reftable_writer_free(w);
+
+ block_source_from_strbuf(&source, &buf);
+ err = reftable_new_reader(&rd, &source, "filename");
+ EXPECT_ERR(err);
+
+ reftable_table_from_reader(&tab, rd);
+
+ for (i = 0; i < ARRAY_SIZE(cases); i++) {
+ struct modification mod = {
+ .tab = tab,
+ };
+
+ if (cases[i].add) {
+ mod.add = &cases[i].add;
+ mod.add_len = 1;
+ }
+ if (cases[i].del) {
+ mod.del = &cases[i].del;
+ mod.del_len = 1;
+ }
+
+ err = modification_validate(&mod);
+ EXPECT(err == cases[i].error_code);
+ }
+
+ reftable_reader_free(rd);
+ strbuf_release(&buf);
+}
+
+int refname_test_main(int argc, const char *argv[])
+{
+ RUN_TEST(test_conflict);
+ return 0;
+}
diff --git a/reftable/reftable-blocksource.h b/reftable/reftable-blocksource.h
new file mode 100644
index 0000000..5aa3990
--- /dev/null
+++ b/reftable/reftable-blocksource.h
@@ -0,0 +1,49 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef REFTABLE_BLOCKSOURCE_H
+#define REFTABLE_BLOCKSOURCE_H
+
+#include <stdint.h>
+
+/* block_source is a generic wrapper for a seekable readable file.
+ */
+struct reftable_block_source {
+ struct reftable_block_source_vtable *ops;
+ void *arg;
+};
+
+/* a contiguous segment of bytes. It keeps track of its generating block_source
+ * so it can return itself into the pool. */
+struct reftable_block {
+ uint8_t *data;
+ int len;
+ struct reftable_block_source source;
+};
+
+/* block_source_vtable are the operations that make up block_source */
+struct reftable_block_source_vtable {
+ /* returns the size of a block source */
+ uint64_t (*size)(void *source);
+
+ /* reads a segment from the block source. It is an error to read
+ beyond the end of the block */
+ int (*read_block)(void *source, struct reftable_block *dest,
+ uint64_t off, uint32_t size);
+ /* mark the block as read; may return the data back to malloc */
+ void (*return_block)(void *source, struct reftable_block *blockp);
+
+ /* release all resources associated with the block source */
+ void (*close)(void *source);
+};
+
+/* opens a file on the file system as a block_source */
+int reftable_block_source_from_file(struct reftable_block_source *block_src,
+ const char *name);
+
+#endif
diff --git a/reftable/reftable-error.h b/reftable/reftable-error.h
new file mode 100644
index 0000000..6f89bed
--- /dev/null
+++ b/reftable/reftable-error.h
@@ -0,0 +1,62 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef REFTABLE_ERROR_H
+#define REFTABLE_ERROR_H
+
+/*
+ * Errors in reftable calls are signaled with negative integer return values. 0
+ * means success.
+ */
+enum reftable_error {
+ /* Unexpected file system behavior */
+ REFTABLE_IO_ERROR = -2,
+
+ /* Format inconsistency on reading data */
+ REFTABLE_FORMAT_ERROR = -3,
+
+ /* File does not exist. Returned from block_source_from_file(), because
+ * it needs special handling in stack.
+ */
+ REFTABLE_NOT_EXIST_ERROR = -4,
+
+ /* Trying to write out-of-date data. */
+ REFTABLE_LOCK_ERROR = -5,
+
+ /* Misuse of the API:
+ * - on writing a record with NULL refname.
+ * - on writing a reftable_ref_record outside the table limits
+ * - on writing a ref or log record before the stack's
+ * next_update_inde*x
+ * - on writing a log record with multiline message with
+ * exact_log_message unset
+ * - on reading a reftable_ref_record from log iterator, or vice versa.
+ *
+ * When a call misuses the API, the internal state of the library is
+ * kept unchanged.
+ */
+ REFTABLE_API_ERROR = -6,
+
+ /* Decompression error */
+ REFTABLE_ZLIB_ERROR = -7,
+
+ /* Wrote a table without blocks. */
+ REFTABLE_EMPTY_TABLE_ERROR = -8,
+
+ /* Dir/file conflict. */
+ REFTABLE_NAME_CONFLICT = -9,
+
+ /* Invalid ref name. */
+ REFTABLE_REFNAME_ERROR = -10,
+};
+
+/* convert the numeric error code to a string. The string should not be
+ * deallocated. */
+const char *reftable_error_str(int err);
+
+#endif
diff --git a/reftable/reftable-generic.h b/reftable/reftable-generic.h
new file mode 100644
index 0000000..d239751
--- /dev/null
+++ b/reftable/reftable-generic.h
@@ -0,0 +1,47 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef REFTABLE_GENERIC_H
+#define REFTABLE_GENERIC_H
+
+#include "reftable-iterator.h"
+
+struct reftable_table_vtable;
+
+/*
+ * Provides a unified API for reading tables, either merged tables, or single
+ * readers. */
+struct reftable_table {
+ struct reftable_table_vtable *ops;
+ void *table_arg;
+};
+
+int reftable_table_seek_log(struct reftable_table *tab,
+ struct reftable_iterator *it, const char *name);
+
+int reftable_table_seek_ref(struct reftable_table *tab,
+ struct reftable_iterator *it, const char *name);
+
+/* returns the hash ID from a generic reftable_table */
+uint32_t reftable_table_hash_id(struct reftable_table *tab);
+
+/* returns the max update_index covered by this table. */
+uint64_t reftable_table_max_update_index(struct reftable_table *tab);
+
+/* returns the min update_index covered by this table. */
+uint64_t reftable_table_min_update_index(struct reftable_table *tab);
+
+/* convenience function to read a single ref. Returns < 0 for error, 0
+ for success, and 1 if ref not found. */
+int reftable_table_read_ref(struct reftable_table *tab, const char *name,
+ struct reftable_ref_record *ref);
+
+/* dump table contents onto stdout for debugging */
+int reftable_table_print(struct reftable_table *tab);
+
+#endif
diff --git a/reftable/reftable-iterator.h b/reftable/reftable-iterator.h
new file mode 100644
index 0000000..d3eee7a
--- /dev/null
+++ b/reftable/reftable-iterator.h
@@ -0,0 +1,39 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef REFTABLE_ITERATOR_H
+#define REFTABLE_ITERATOR_H
+
+#include "reftable-record.h"
+
+struct reftable_iterator_vtable;
+
+/* iterator is the generic interface for walking over data stored in a
+ * reftable.
+ */
+struct reftable_iterator {
+ struct reftable_iterator_vtable *ops;
+ void *iter_arg;
+};
+
+/* reads the next reftable_ref_record. Returns < 0 for error, 0 for OK and > 0:
+ * end of iteration.
+ */
+int reftable_iterator_next_ref(struct reftable_iterator *it,
+ struct reftable_ref_record *ref);
+
+/* reads the next reftable_log_record. Returns < 0 for error, 0 for OK and > 0:
+ * end of iteration.
+ */
+int reftable_iterator_next_log(struct reftable_iterator *it,
+ struct reftable_log_record *log);
+
+/* releases resources associated with an iterator. */
+void reftable_iterator_destroy(struct reftable_iterator *it);
+
+#endif
diff --git a/reftable/reftable-malloc.h b/reftable/reftable-malloc.h
new file mode 100644
index 0000000..5f2185f
--- /dev/null
+++ b/reftable/reftable-malloc.h
@@ -0,0 +1,18 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef REFTABLE_H
+#define REFTABLE_H
+
+#include <stddef.h>
+
+/* Overrides the functions to use for memory management. */
+void reftable_set_alloc(void *(*malloc)(size_t),
+ void *(*realloc)(void *, size_t), void (*free)(void *));
+
+#endif
diff --git a/reftable/reftable-merged.h b/reftable/reftable-merged.h
new file mode 100644
index 0000000..1a6d169
--- /dev/null
+++ b/reftable/reftable-merged.h
@@ -0,0 +1,72 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef REFTABLE_MERGED_H
+#define REFTABLE_MERGED_H
+
+#include "reftable-iterator.h"
+
+/*
+ * Merged tables
+ *
+ * A ref database kept in a sequence of table files. The merged_table presents a
+ * unified view to reading (seeking, iterating) a sequence of immutable tables.
+ *
+ * The merged tables are on purpose kept disconnected from their actual storage
+ * (eg. files on disk), because it is useful to merge tables aren't files. For
+ * example, the per-workspace and global ref namespace can be implemented as a
+ * merged table of two stacks of file-backed reftables.
+ */
+
+/* A merged table is implements seeking/iterating over a stack of tables. */
+struct reftable_merged_table;
+
+/* A generic reftable; see below. */
+struct reftable_table;
+
+/* reftable_new_merged_table creates a new merged table. It takes ownership of
+ the stack array.
+*/
+int reftable_new_merged_table(struct reftable_merged_table **dest,
+ struct reftable_table *stack, int n,
+ uint32_t hash_id);
+
+/* returns an iterator positioned just before 'name' */
+int reftable_merged_table_seek_ref(struct reftable_merged_table *mt,
+ struct reftable_iterator *it,
+ const char *name);
+
+/* returns an iterator for log entry, at given update_index */
+int reftable_merged_table_seek_log_at(struct reftable_merged_table *mt,
+ struct reftable_iterator *it,
+ const char *name, uint64_t update_index);
+
+/* like reftable_merged_table_seek_log_at but look for the newest entry. */
+int reftable_merged_table_seek_log(struct reftable_merged_table *mt,
+ struct reftable_iterator *it,
+ const char *name);
+
+/* returns the max update_index covered by this merged table. */
+uint64_t
+reftable_merged_table_max_update_index(struct reftable_merged_table *mt);
+
+/* returns the min update_index covered by this merged table. */
+uint64_t
+reftable_merged_table_min_update_index(struct reftable_merged_table *mt);
+
+/* releases memory for the merged_table */
+void reftable_merged_table_free(struct reftable_merged_table *m);
+
+/* return the hash ID of the merged table. */
+uint32_t reftable_merged_table_hash_id(struct reftable_merged_table *m);
+
+/* create a generic table from reftable_merged_table */
+void reftable_table_from_merged_table(struct reftable_table *tab,
+ struct reftable_merged_table *table);
+
+#endif
diff --git a/reftable/reftable-reader.h b/reftable/reftable-reader.h
new file mode 100644
index 0000000..4a4bc2f
--- /dev/null
+++ b/reftable/reftable-reader.h
@@ -0,0 +1,101 @@
+/*
+ Copyright 2020 Google LLC
+
+ Use of this source code is governed by a BSD-style
+ license that can be found in the LICENSE file or at
+ https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef REFTABLE_READER_H
+#define REFTABLE_READER_H
+
+#include "reftable-iterator.h"
+#include "reftable-blocksource.h"
+
+/*
+ * Reading single tables
+ *
+ * The follow routines are for reading single files. For an
+ * application-level interface, skip ahead to struct
+ * reftable_merged_table and struct reftable_stack.
+ */
+
+/* The reader struct is a handle to an open reftable file. */
+struct reftable_reader;
+
+/* Generic table. */
+struct reftable_table;
+
+/* reftable_new_reader opens a reftable for reading. If successful,
+ * returns 0 code and sets pp. The name is used for creating a
+ * stack. Typically, it is the basename of the file. The block source
+ * `src` is owned by the reader, and is closed on calling
+ * reftable_reader_destroy(). On error, the block source `src` is
+ * closed as well.
+ */
+int reftable_new_reader(struct reftable_reader **pp,
+ struct reftable_block_source *src, const char *name);
+
+/* reftable_reader_seek_ref returns an iterator where 'name' would be inserted
+ in the table. To seek to the start of the table, use name = "".
+
+ example:
+
+ struct reftable_reader *r = NULL;
+ int err = reftable_new_reader(&r, &src, "filename");
+ if (err < 0) { ... }
+ struct reftable_iterator it = {0};
+ err = reftable_reader_seek_ref(r, &it, "refs/heads/master");
+ if (err < 0) { ... }
+ struct reftable_ref_record ref = {0};
+ while (1) {
+ err = reftable_iterator_next_ref(&it, &ref);
+ if (err > 0) {
+ break;
+ }
+ if (err < 0) {
+ ..error handling..
+ }
+ ..found..
+ }
+ reftable_iterator_destroy(&it);
+ reftable_ref_record_release(&ref);
+*/
+int reftable_reader_seek_ref(struct reftable_reader *r,
+ struct reftable_iterator *it, const char *name);
+
+/* returns the hash ID used in this table. */
+uint32_t reftable_reader_hash_id(struct reftable_reader *r);
+
+/* seek to logs for the given name, older than update_index. To seek to the
+ start of the table, use name = "".
+*/
+int reftable_reader_seek_log_at(struct reftable_reader *r,
+ struct reftable_iterator *it, const char *name,
+ uint64_t update_index);
+
+/* seek to newest log entry for given name. */
+int reftable_reader_seek_log(struct reftable_reader *r,
+ struct reftable_iterator *it, const char *name);
+
+/* closes and deallocates a reader. */
+void reftable_reader_free(struct reftable_reader *);
+
+/* return an iterator for the refs pointing to `oid`. */
+int reftable_reader_refs_for(struct reftable_reader *r,
+ struct reftable_iterator *it, uint8_t *oid);
+
+/* return the max_update_index for a table */
+uint64_t reftable_reader_max_update_index(struct reftable_reader *r);
+
+/* return the min_update_index for a table */
+uint64_t reftable_reader_min_update_index(struct reftable_reader *r);
+
+/* creates a generic table from a file reader. */
+void reftable_table_from_reader(struct reftable_table *tab,
+ struct reftable_reader *reader);
+
+/* print table onto stdout for debugging. */
+int reftable_reader_print_file(const char *tablename);
+
+#endif
diff --git a/reftable/reftable-record.h b/reftable/reftable-record.h
new file mode 100644
index 0000000..7985b94
--- /dev/null
+++ b/reftable/reftable-record.h
@@ -0,0 +1,114 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef REFTABLE_RECORD_H
+#define REFTABLE_RECORD_H
+
+#include <stdint.h>
+
+/*
+ * Basic data types
+ *
+ * Reftables store the state of each ref in struct reftable_ref_record, and they
+ * store a sequence of reflog updates in struct reftable_log_record.
+ */
+
+/* reftable_ref_record holds a ref database entry target_value */
+struct reftable_ref_record {
+ char *refname; /* Name of the ref, malloced. */
+ uint64_t update_index; /* Logical timestamp at which this value is
+ * written */
+
+ enum {
+ /* tombstone to hide deletions from earlier tables */
+ REFTABLE_REF_DELETION = 0x0,
+
+ /* a simple ref */
+ REFTABLE_REF_VAL1 = 0x1,
+ /* a tag, plus its peeled hash */
+ REFTABLE_REF_VAL2 = 0x2,
+
+ /* a symbolic reference */
+ REFTABLE_REF_SYMREF = 0x3,
+#define REFTABLE_NR_REF_VALUETYPES 4
+ } value_type;
+ union {
+ uint8_t *val1; /* malloced hash. */
+ struct {
+ uint8_t *value; /* first value, malloced hash */
+ uint8_t *target_value; /* second value, malloced hash */
+ } val2;
+ char *symref; /* referent, malloced 0-terminated string */
+ } value;
+};
+
+/* Returns the first hash, or NULL if `rec` is not of type
+ * REFTABLE_REF_VAL1 or REFTABLE_REF_VAL2. */
+uint8_t *reftable_ref_record_val1(struct reftable_ref_record *rec);
+
+/* Returns the second hash, or NULL if `rec` is not of type
+ * REFTABLE_REF_VAL2. */
+uint8_t *reftable_ref_record_val2(struct reftable_ref_record *rec);
+
+/* returns whether 'ref' represents a deletion */
+int reftable_ref_record_is_deletion(const struct reftable_ref_record *ref);
+
+/* prints a reftable_ref_record onto stdout. Useful for debugging. */
+void reftable_ref_record_print(struct reftable_ref_record *ref,
+ uint32_t hash_id);
+
+/* frees and nulls all pointer values inside `ref`. */
+void reftable_ref_record_release(struct reftable_ref_record *ref);
+
+/* returns whether two reftable_ref_records are the same. Useful for testing. */
+int reftable_ref_record_equal(struct reftable_ref_record *a,
+ struct reftable_ref_record *b, int hash_size);
+
+/* reftable_log_record holds a reflog entry */
+struct reftable_log_record {
+ char *refname;
+ uint64_t update_index; /* logical timestamp of a transactional update.
+ */
+
+ enum {
+ /* tombstone to hide deletions from earlier tables */
+ REFTABLE_LOG_DELETION = 0x0,
+
+ /* a simple update */
+ REFTABLE_LOG_UPDATE = 0x1,
+#define REFTABLE_NR_LOG_VALUETYPES 2
+ } value_type;
+
+ union {
+ struct {
+ uint8_t *new_hash;
+ uint8_t *old_hash;
+ char *name;
+ char *email;
+ uint64_t time;
+ int16_t tz_offset;
+ char *message;
+ } update;
+ };
+};
+
+/* returns whether 'ref' represents the deletion of a log record. */
+int reftable_log_record_is_deletion(const struct reftable_log_record *log);
+
+/* frees and nulls all pointer values. */
+void reftable_log_record_release(struct reftable_log_record *log);
+
+/* returns whether two records are equal. Useful for testing. */
+int reftable_log_record_equal(struct reftable_log_record *a,
+ struct reftable_log_record *b, int hash_size);
+
+/* dumps a reftable_log_record on stdout, for debugging/testing. */
+void reftable_log_record_print(struct reftable_log_record *log,
+ uint32_t hash_id);
+
+#endif
diff --git a/reftable/reftable-stack.h b/reftable/reftable-stack.h
new file mode 100644
index 0000000..1b602dd
--- /dev/null
+++ b/reftable/reftable-stack.h
@@ -0,0 +1,128 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef REFTABLE_STACK_H
+#define REFTABLE_STACK_H
+
+#include "reftable-writer.h"
+
+/*
+ * The stack presents an interface to a mutable sequence of reftables.
+
+ * A stack can be mutated by pushing a table to the top of the stack.
+
+ * The reftable_stack automatically compacts files on disk to ensure good
+ * amortized performance.
+ *
+ * For windows and other platforms that cannot have open files as rename
+ * destinations, concurrent access from multiple processes needs the rand()
+ * random seed to be randomized.
+ */
+struct reftable_stack;
+
+/* open a new reftable stack. The tables along with the table list will be
+ * stored in 'dir'. Typically, this should be .git/reftables.
+ */
+int reftable_new_stack(struct reftable_stack **dest, const char *dir,
+ struct reftable_write_options config);
+
+/* returns the update_index at which a next table should be written. */
+uint64_t reftable_stack_next_update_index(struct reftable_stack *st);
+
+/* holds a transaction to add tables at the top of a stack. */
+struct reftable_addition;
+
+/*
+ * returns a new transaction to add reftables to the given stack. As a side
+ * effect, the ref database is locked.
+ */
+int reftable_stack_new_addition(struct reftable_addition **dest,
+ struct reftable_stack *st);
+
+/* Adds a reftable to transaction. */
+int reftable_addition_add(struct reftable_addition *add,
+ int (*write_table)(struct reftable_writer *wr,
+ void *arg),
+ void *arg);
+
+/* Commits the transaction, releasing the lock. After calling this,
+ * reftable_addition_destroy should still be called.
+ */
+int reftable_addition_commit(struct reftable_addition *add);
+
+/* Release all non-committed data from the transaction, and deallocate the
+ * transaction. Releases the lock if held. */
+void reftable_addition_destroy(struct reftable_addition *add);
+
+/* add a new table to the stack. The write_table function must call
+ * reftable_writer_set_limits, add refs and return an error value. */
+int reftable_stack_add(struct reftable_stack *st,
+ int (*write_table)(struct reftable_writer *wr,
+ void *write_arg),
+ void *write_arg);
+
+/* returns the merged_table for seeking. This table is valid until the
+ * next write or reload, and should not be closed or deleted.
+ */
+struct reftable_merged_table *
+reftable_stack_merged_table(struct reftable_stack *st);
+
+/* frees all resources associated with the stack. */
+void reftable_stack_destroy(struct reftable_stack *st);
+
+/* Reloads the stack if necessary. This is very cheap to run if the stack was up
+ * to date */
+int reftable_stack_reload(struct reftable_stack *st);
+
+/* Policy for expiring reflog entries. */
+struct reftable_log_expiry_config {
+ /* Drop entries older than this timestamp */
+ uint64_t time;
+
+ /* Drop older entries */
+ uint64_t min_update_index;
+};
+
+/* compacts all reftables into a giant table. Expire reflog entries if config is
+ * non-NULL */
+int reftable_stack_compact_all(struct reftable_stack *st,
+ struct reftable_log_expiry_config *config);
+
+/* heuristically compact unbalanced table stack. */
+int reftable_stack_auto_compact(struct reftable_stack *st);
+
+/* delete stale .ref tables. */
+int reftable_stack_clean(struct reftable_stack *st);
+
+/* convenience function to read a single ref. Returns < 0 for error, 0 for
+ * success, and 1 if ref not found. */
+int reftable_stack_read_ref(struct reftable_stack *st, const char *refname,
+ struct reftable_ref_record *ref);
+
+/* convenience function to read a single log. Returns < 0 for error, 0 for
+ * success, and 1 if ref not found. */
+int reftable_stack_read_log(struct reftable_stack *st, const char *refname,
+ struct reftable_log_record *log);
+
+/* statistics on past compactions. */
+struct reftable_compaction_stats {
+ uint64_t bytes; /* total number of bytes written */
+ uint64_t entries_written; /* total number of entries written, including
+ failures. */
+ int attempts; /* how often we tried to compact */
+ int failures; /* failures happen on concurrent updates */
+};
+
+/* return statistics for compaction up till now. */
+struct reftable_compaction_stats *
+reftable_stack_compaction_stats(struct reftable_stack *st);
+
+/* print the entire stack represented by the directory */
+int reftable_stack_print_directory(const char *stackdir, uint32_t hash_id);
+
+#endif
diff --git a/reftable/reftable-tests.h b/reftable/reftable-tests.h
new file mode 100644
index 0000000..0019cbc
--- /dev/null
+++ b/reftable/reftable-tests.h
@@ -0,0 +1,23 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef REFTABLE_TESTS_H
+#define REFTABLE_TESTS_H
+
+int basics_test_main(int argc, const char **argv);
+int block_test_main(int argc, const char **argv);
+int merged_test_main(int argc, const char **argv);
+int pq_test_main(int argc, const char **argv);
+int record_test_main(int argc, const char **argv);
+int refname_test_main(int argc, const char **argv);
+int readwrite_test_main(int argc, const char **argv);
+int stack_test_main(int argc, const char **argv);
+int tree_test_main(int argc, const char **argv);
+int reftable_dump_main(int argc, char *const *argv);
+
+#endif
diff --git a/reftable/reftable-writer.h b/reftable/reftable-writer.h
new file mode 100644
index 0000000..af36462
--- /dev/null
+++ b/reftable/reftable-writer.h
@@ -0,0 +1,148 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef REFTABLE_WRITER_H
+#define REFTABLE_WRITER_H
+
+#include "reftable-record.h"
+
+#include <stdint.h>
+#include <unistd.h> /* ssize_t */
+
+/* Writing single reftables */
+
+/* reftable_write_options sets options for writing a single reftable. */
+struct reftable_write_options {
+ /* boolean: do not pad out blocks to block size. */
+ unsigned unpadded : 1;
+
+ /* the blocksize. Should be less than 2^24. */
+ uint32_t block_size;
+
+ /* boolean: do not generate a SHA1 => ref index. */
+ unsigned skip_index_objects : 1;
+
+ /* how often to write complete keys in each block. */
+ int restart_interval;
+
+ /* 4-byte identifier ("sha1", "s256") of the hash.
+ * Defaults to SHA1 if unset
+ */
+ uint32_t hash_id;
+
+ /* boolean: do not check ref names for validity or dir/file conflicts.
+ */
+ unsigned skip_name_check : 1;
+
+ /* boolean: copy log messages exactly. If unset, check that the message
+ * is a single line, and add '\n' if missing.
+ */
+ unsigned exact_log_message : 1;
+};
+
+/* reftable_block_stats holds statistics for a single block type */
+struct reftable_block_stats {
+ /* total number of entries written */
+ int entries;
+ /* total number of key restarts */
+ int restarts;
+ /* total number of blocks */
+ int blocks;
+ /* total number of index blocks */
+ int index_blocks;
+ /* depth of the index */
+ int max_index_level;
+
+ /* offset of the first block for this type */
+ uint64_t offset;
+ /* offset of the top level index block for this type, or 0 if not
+ * present */
+ uint64_t index_offset;
+};
+
+/* stats holds overall statistics for a single reftable */
+struct reftable_stats {
+ /* total number of blocks written. */
+ int blocks;
+ /* stats for ref data */
+ struct reftable_block_stats ref_stats;
+ /* stats for the SHA1 to ref map. */
+ struct reftable_block_stats obj_stats;
+ /* stats for index blocks */
+ struct reftable_block_stats idx_stats;
+ /* stats for log blocks */
+ struct reftable_block_stats log_stats;
+
+ /* disambiguation length of shortened object IDs. */
+ int object_id_len;
+};
+
+/* reftable_new_writer creates a new writer */
+struct reftable_writer *
+reftable_new_writer(ssize_t (*writer_func)(void *, const void *, size_t),
+ void *writer_arg, struct reftable_write_options *opts);
+
+/* Set the range of update indices for the records we will add. When writing a
+ table into a stack, the min should be at least
+ reftable_stack_next_update_index(), or REFTABLE_API_ERROR is returned.
+
+ For transactional updates to a stack, typically min==max, and the
+ update_index can be obtained by inspeciting the stack. When converting an
+ existing ref database into a single reftable, this would be a range of
+ update-index timestamps.
+ */
+void reftable_writer_set_limits(struct reftable_writer *w, uint64_t min,
+ uint64_t max);
+
+/*
+ Add a reftable_ref_record. The record should have names that come after
+ already added records.
+
+ The update_index must be within the limits set by
+ reftable_writer_set_limits(), or REFTABLE_API_ERROR is returned. It is an
+ REFTABLE_API_ERROR error to write a ref record after a log record.
+*/
+int reftable_writer_add_ref(struct reftable_writer *w,
+ struct reftable_ref_record *ref);
+
+/*
+ Convenience function to add multiple reftable_ref_records; the function sorts
+ the records before adding them, reordering the records array passed in.
+*/
+int reftable_writer_add_refs(struct reftable_writer *w,
+ struct reftable_ref_record *refs, int n);
+
+/*
+ adds reftable_log_records. Log records are keyed by (refname, decreasing
+ update_index). The key for the record added must come after the already added
+ log records.
+*/
+int reftable_writer_add_log(struct reftable_writer *w,
+ struct reftable_log_record *log);
+
+/*
+ Convenience function to add multiple reftable_log_records; the function sorts
+ the records before adding them, reordering records array passed in.
+*/
+int reftable_writer_add_logs(struct reftable_writer *w,
+ struct reftable_log_record *logs, int n);
+
+/* reftable_writer_close finalizes the reftable. The writer is retained so
+ * statistics can be inspected. */
+int reftable_writer_close(struct reftable_writer *w);
+
+/* writer_stats returns the statistics on the reftable being written.
+
+ This struct becomes invalid when the writer is freed.
+ */
+const struct reftable_stats *writer_stats(struct reftable_writer *w);
+
+/* reftable_writer_free deallocates memory for the writer */
+void reftable_writer_free(struct reftable_writer *w);
+
+#endif
diff --git a/reftable/reftable.c b/reftable/reftable.c
new file mode 100644
index 0000000..0e4607a
--- /dev/null
+++ b/reftable/reftable.c
@@ -0,0 +1,115 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "basics.h"
+#include "record.h"
+#include "generic.h"
+#include "reftable-iterator.h"
+#include "reftable-generic.h"
+
+int reftable_table_seek_ref(struct reftable_table *tab,
+ struct reftable_iterator *it, const char *name)
+{
+ struct reftable_ref_record ref = {
+ .refname = (char *)name,
+ };
+ struct reftable_record rec = { NULL };
+ reftable_record_from_ref(&rec, &ref);
+ return tab->ops->seek_record(tab->table_arg, it, &rec);
+}
+
+int reftable_table_read_ref(struct reftable_table *tab, const char *name,
+ struct reftable_ref_record *ref)
+{
+ struct reftable_iterator it = { NULL };
+ int err = reftable_table_seek_ref(tab, &it, name);
+ if (err)
+ goto done;
+
+ err = reftable_iterator_next_ref(&it, ref);
+ if (err)
+ goto done;
+
+ if (strcmp(ref->refname, name) ||
+ reftable_ref_record_is_deletion(ref)) {
+ reftable_ref_record_release(ref);
+ err = 1;
+ goto done;
+ }
+
+done:
+ reftable_iterator_destroy(&it);
+ return err;
+}
+
+uint64_t reftable_table_max_update_index(struct reftable_table *tab)
+{
+ return tab->ops->max_update_index(tab->table_arg);
+}
+
+uint64_t reftable_table_min_update_index(struct reftable_table *tab)
+{
+ return tab->ops->min_update_index(tab->table_arg);
+}
+
+uint32_t reftable_table_hash_id(struct reftable_table *tab)
+{
+ return tab->ops->hash_id(tab->table_arg);
+}
+
+void reftable_iterator_destroy(struct reftable_iterator *it)
+{
+ if (!it->ops) {
+ return;
+ }
+ it->ops->close(it->iter_arg);
+ it->ops = NULL;
+ FREE_AND_NULL(it->iter_arg);
+}
+
+int reftable_iterator_next_ref(struct reftable_iterator *it,
+ struct reftable_ref_record *ref)
+{
+ struct reftable_record rec = { NULL };
+ reftable_record_from_ref(&rec, ref);
+ return iterator_next(it, &rec);
+}
+
+int reftable_iterator_next_log(struct reftable_iterator *it,
+ struct reftable_log_record *log)
+{
+ struct reftable_record rec = { NULL };
+ reftable_record_from_log(&rec, log);
+ return iterator_next(it, &rec);
+}
+
+int iterator_next(struct reftable_iterator *it, struct reftable_record *rec)
+{
+ return it->ops->next(it->iter_arg, rec);
+}
+
+static int empty_iterator_next(void *arg, struct reftable_record *rec)
+{
+ return 1;
+}
+
+static void empty_iterator_close(void *arg)
+{
+}
+
+static struct reftable_iterator_vtable empty_vtable = {
+ .next = &empty_iterator_next,
+ .close = &empty_iterator_close,
+};
+
+void iterator_set_empty(struct reftable_iterator *it)
+{
+ assert(!it->ops);
+ it->iter_arg = NULL;
+ it->ops = &empty_vtable;
+}
diff --git a/reftable/stack.c b/reftable/stack.c
new file mode 100644
index 0000000..cf3b11a
--- /dev/null
+++ b/reftable/stack.c
@@ -0,0 +1,1396 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "stack.h"
+
+#include "system.h"
+#include "merged.h"
+#include "reader.h"
+#include "refname.h"
+#include "reftable-error.h"
+#include "reftable-record.h"
+#include "reftable-merged.h"
+#include "writer.h"
+
+static int stack_try_add(struct reftable_stack *st,
+ int (*write_table)(struct reftable_writer *wr,
+ void *arg),
+ void *arg);
+static int stack_write_compact(struct reftable_stack *st,
+ struct reftable_writer *wr, int first, int last,
+ struct reftable_log_expiry_config *config);
+static int stack_check_addition(struct reftable_stack *st,
+ const char *new_tab_name);
+static void reftable_addition_close(struct reftable_addition *add);
+static int reftable_stack_reload_maybe_reuse(struct reftable_stack *st,
+ int reuse_open);
+
+static void stack_filename(struct strbuf *dest, struct reftable_stack *st,
+ const char *name)
+{
+ strbuf_reset(dest);
+ strbuf_addstr(dest, st->reftable_dir);
+ strbuf_addstr(dest, "/");
+ strbuf_addstr(dest, name);
+}
+
+static ssize_t reftable_fd_write(void *arg, const void *data, size_t sz)
+{
+ int *fdp = (int *)arg;
+ return write(*fdp, data, sz);
+}
+
+int reftable_new_stack(struct reftable_stack **dest, const char *dir,
+ struct reftable_write_options config)
+{
+ struct reftable_stack *p =
+ reftable_calloc(sizeof(struct reftable_stack));
+ struct strbuf list_file_name = STRBUF_INIT;
+ int err = 0;
+
+ if (config.hash_id == 0) {
+ config.hash_id = GIT_SHA1_FORMAT_ID;
+ }
+
+ *dest = NULL;
+
+ strbuf_reset(&list_file_name);
+ strbuf_addstr(&list_file_name, dir);
+ strbuf_addstr(&list_file_name, "/tables.list");
+
+ p->list_file = strbuf_detach(&list_file_name, NULL);
+ p->reftable_dir = xstrdup(dir);
+ p->config = config;
+
+ err = reftable_stack_reload_maybe_reuse(p, 1);
+ if (err < 0) {
+ reftable_stack_destroy(p);
+ } else {
+ *dest = p;
+ }
+ return err;
+}
+
+static int fd_read_lines(int fd, char ***namesp)
+{
+ off_t size = lseek(fd, 0, SEEK_END);
+ char *buf = NULL;
+ int err = 0;
+ if (size < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+ err = lseek(fd, 0, SEEK_SET);
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+
+ buf = reftable_malloc(size + 1);
+ if (read(fd, buf, size) != size) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+ buf[size] = 0;
+
+ parse_names(buf, size, namesp);
+
+done:
+ reftable_free(buf);
+ return err;
+}
+
+int read_lines(const char *filename, char ***namesp)
+{
+ int fd = open(filename, O_RDONLY, 0644);
+ int err = 0;
+ if (fd < 0) {
+ if (errno == ENOENT) {
+ *namesp = reftable_calloc(sizeof(char *));
+ return 0;
+ }
+
+ return REFTABLE_IO_ERROR;
+ }
+ err = fd_read_lines(fd, namesp);
+ close(fd);
+ return err;
+}
+
+struct reftable_merged_table *
+reftable_stack_merged_table(struct reftable_stack *st)
+{
+ return st->merged;
+}
+
+static int has_name(char **names, const char *name)
+{
+ while (*names) {
+ if (!strcmp(*names, name))
+ return 1;
+ names++;
+ }
+ return 0;
+}
+
+/* Close and free the stack */
+void reftable_stack_destroy(struct reftable_stack *st)
+{
+ char **names = NULL;
+ int err = 0;
+ if (st->merged) {
+ reftable_merged_table_free(st->merged);
+ st->merged = NULL;
+ }
+
+ err = read_lines(st->list_file, &names);
+ if (err < 0) {
+ FREE_AND_NULL(names);
+ }
+
+ if (st->readers) {
+ int i = 0;
+ struct strbuf filename = STRBUF_INIT;
+ for (i = 0; i < st->readers_len; i++) {
+ const char *name = reader_name(st->readers[i]);
+ strbuf_reset(&filename);
+ if (names && !has_name(names, name)) {
+ stack_filename(&filename, st, name);
+ }
+ reftable_reader_free(st->readers[i]);
+
+ if (filename.len) {
+ // On Windows, can only unlink after closing.
+ unlink(filename.buf);
+ }
+ }
+ strbuf_release(&filename);
+ st->readers_len = 0;
+ FREE_AND_NULL(st->readers);
+ }
+ FREE_AND_NULL(st->list_file);
+ FREE_AND_NULL(st->reftable_dir);
+ reftable_free(st);
+ free_names(names);
+}
+
+static struct reftable_reader **stack_copy_readers(struct reftable_stack *st,
+ int cur_len)
+{
+ struct reftable_reader **cur =
+ reftable_calloc(sizeof(struct reftable_reader *) * cur_len);
+ int i = 0;
+ for (i = 0; i < cur_len; i++) {
+ cur[i] = st->readers[i];
+ }
+ return cur;
+}
+
+static int reftable_stack_reload_once(struct reftable_stack *st, char **names,
+ int reuse_open)
+{
+ int cur_len = !st->merged ? 0 : st->merged->stack_len;
+ struct reftable_reader **cur = stack_copy_readers(st, cur_len);
+ int err = 0;
+ int names_len = names_length(names);
+ struct reftable_reader **new_readers =
+ reftable_calloc(sizeof(struct reftable_reader *) * names_len);
+ struct reftable_table *new_tables =
+ reftable_calloc(sizeof(struct reftable_table) * names_len);
+ int new_readers_len = 0;
+ struct reftable_merged_table *new_merged = NULL;
+ int i;
+
+ while (*names) {
+ struct reftable_reader *rd = NULL;
+ char *name = *names++;
+
+ /* this is linear; we assume compaction keeps the number of
+ tables under control so this is not quadratic. */
+ int j = 0;
+ for (j = 0; reuse_open && j < cur_len; j++) {
+ if (cur[j] && 0 == strcmp(cur[j]->name, name)) {
+ rd = cur[j];
+ cur[j] = NULL;
+ break;
+ }
+ }
+
+ if (!rd) {
+ struct reftable_block_source src = { NULL };
+ struct strbuf table_path = STRBUF_INIT;
+ stack_filename(&table_path, st, name);
+
+ err = reftable_block_source_from_file(&src,
+ table_path.buf);
+ strbuf_release(&table_path);
+
+ if (err < 0)
+ goto done;
+
+ err = reftable_new_reader(&rd, &src, name);
+ if (err < 0)
+ goto done;
+ }
+
+ new_readers[new_readers_len] = rd;
+ reftable_table_from_reader(&new_tables[new_readers_len], rd);
+ new_readers_len++;
+ }
+
+ /* success! */
+ err = reftable_new_merged_table(&new_merged, new_tables,
+ new_readers_len, st->config.hash_id);
+ if (err < 0)
+ goto done;
+
+ new_tables = NULL;
+ st->readers_len = new_readers_len;
+ if (st->merged) {
+ merged_table_release(st->merged);
+ reftable_merged_table_free(st->merged);
+ }
+ if (st->readers) {
+ reftable_free(st->readers);
+ }
+ st->readers = new_readers;
+ new_readers = NULL;
+ new_readers_len = 0;
+
+ new_merged->suppress_deletions = 1;
+ st->merged = new_merged;
+ for (i = 0; i < cur_len; i++) {
+ if (cur[i]) {
+ const char *name = reader_name(cur[i]);
+ struct strbuf filename = STRBUF_INIT;
+ stack_filename(&filename, st, name);
+
+ reader_close(cur[i]);
+ reftable_reader_free(cur[i]);
+
+ // On Windows, can only unlink after closing.
+ unlink(filename.buf);
+
+ strbuf_release(&filename);
+ }
+ }
+
+done:
+ for (i = 0; i < new_readers_len; i++) {
+ reader_close(new_readers[i]);
+ reftable_reader_free(new_readers[i]);
+ }
+ reftable_free(new_readers);
+ reftable_free(new_tables);
+ reftable_free(cur);
+ return err;
+}
+
+/* return negative if a before b. */
+static int tv_cmp(struct timeval *a, struct timeval *b)
+{
+ time_t diff = a->tv_sec - b->tv_sec;
+ int udiff = a->tv_usec - b->tv_usec;
+
+ if (diff != 0)
+ return diff;
+
+ return udiff;
+}
+
+static int reftable_stack_reload_maybe_reuse(struct reftable_stack *st,
+ int reuse_open)
+{
+ struct timeval deadline = { 0 };
+ int err = gettimeofday(&deadline, NULL);
+ int64_t delay = 0;
+ int tries = 0;
+ if (err < 0)
+ return err;
+
+ deadline.tv_sec += 3;
+ while (1) {
+ char **names = NULL;
+ char **names_after = NULL;
+ struct timeval now = { 0 };
+ int err = gettimeofday(&now, NULL);
+ int err2 = 0;
+ if (err < 0) {
+ return err;
+ }
+
+ /* Only look at deadlines after the first few times. This
+ simplifies debugging in GDB */
+ tries++;
+ if (tries > 3 && tv_cmp(&now, &deadline) >= 0) {
+ break;
+ }
+
+ err = read_lines(st->list_file, &names);
+ if (err < 0) {
+ free_names(names);
+ return err;
+ }
+ err = reftable_stack_reload_once(st, names, reuse_open);
+ if (err == 0) {
+ free_names(names);
+ break;
+ }
+ if (err != REFTABLE_NOT_EXIST_ERROR) {
+ free_names(names);
+ return err;
+ }
+
+ /* err == REFTABLE_NOT_EXIST_ERROR can be caused by a concurrent
+ writer. Check if there was one by checking if the name list
+ changed.
+ */
+ err2 = read_lines(st->list_file, &names_after);
+ if (err2 < 0) {
+ free_names(names);
+ return err2;
+ }
+
+ if (names_equal(names_after, names)) {
+ free_names(names);
+ free_names(names_after);
+ return err;
+ }
+ free_names(names);
+ free_names(names_after);
+
+ delay = delay + (delay * rand()) / RAND_MAX + 1;
+ sleep_millisec(delay);
+ }
+
+ return 0;
+}
+
+/* -1 = error
+ 0 = up to date
+ 1 = changed. */
+static int stack_uptodate(struct reftable_stack *st)
+{
+ char **names = NULL;
+ int err = read_lines(st->list_file, &names);
+ int i = 0;
+ if (err < 0)
+ return err;
+
+ for (i = 0; i < st->readers_len; i++) {
+ if (!names[i]) {
+ err = 1;
+ goto done;
+ }
+
+ if (strcmp(st->readers[i]->name, names[i])) {
+ err = 1;
+ goto done;
+ }
+ }
+
+ if (names[st->merged->stack_len]) {
+ err = 1;
+ goto done;
+ }
+
+done:
+ free_names(names);
+ return err;
+}
+
+int reftable_stack_reload(struct reftable_stack *st)
+{
+ int err = stack_uptodate(st);
+ if (err > 0)
+ return reftable_stack_reload_maybe_reuse(st, 1);
+ return err;
+}
+
+int reftable_stack_add(struct reftable_stack *st,
+ int (*write)(struct reftable_writer *wr, void *arg),
+ void *arg)
+{
+ int err = stack_try_add(st, write, arg);
+ if (err < 0) {
+ if (err == REFTABLE_LOCK_ERROR) {
+ /* Ignore error return, we want to propagate
+ REFTABLE_LOCK_ERROR.
+ */
+ reftable_stack_reload(st);
+ }
+ return err;
+ }
+
+ if (!st->disable_auto_compact)
+ return reftable_stack_auto_compact(st);
+
+ return 0;
+}
+
+static void format_name(struct strbuf *dest, uint64_t min, uint64_t max)
+{
+ char buf[100];
+ uint32_t rnd = (uint32_t)rand();
+ snprintf(buf, sizeof(buf), "0x%012" PRIx64 "-0x%012" PRIx64 "-%08x",
+ min, max, rnd);
+ strbuf_reset(dest);
+ strbuf_addstr(dest, buf);
+}
+
+struct reftable_addition {
+ int lock_file_fd;
+ struct strbuf lock_file_name;
+ struct reftable_stack *stack;
+
+ char **new_tables;
+ int new_tables_len;
+ uint64_t next_update_index;
+};
+
+#define REFTABLE_ADDITION_INIT \
+ { \
+ .lock_file_name = STRBUF_INIT \
+ }
+
+static int reftable_stack_init_addition(struct reftable_addition *add,
+ struct reftable_stack *st)
+{
+ int err = 0;
+ add->stack = st;
+
+ strbuf_reset(&add->lock_file_name);
+ strbuf_addstr(&add->lock_file_name, st->list_file);
+ strbuf_addstr(&add->lock_file_name, ".lock");
+
+ add->lock_file_fd = open(add->lock_file_name.buf,
+ O_EXCL | O_CREAT | O_WRONLY, 0644);
+ if (add->lock_file_fd < 0) {
+ if (errno == EEXIST) {
+ err = REFTABLE_LOCK_ERROR;
+ } else {
+ err = REFTABLE_IO_ERROR;
+ }
+ goto done;
+ }
+ err = stack_uptodate(st);
+ if (err < 0)
+ goto done;
+
+ if (err > 1) {
+ err = REFTABLE_LOCK_ERROR;
+ goto done;
+ }
+
+ add->next_update_index = reftable_stack_next_update_index(st);
+done:
+ if (err) {
+ reftable_addition_close(add);
+ }
+ return err;
+}
+
+static void reftable_addition_close(struct reftable_addition *add)
+{
+ int i = 0;
+ struct strbuf nm = STRBUF_INIT;
+ for (i = 0; i < add->new_tables_len; i++) {
+ stack_filename(&nm, add->stack, add->new_tables[i]);
+ unlink(nm.buf);
+ reftable_free(add->new_tables[i]);
+ add->new_tables[i] = NULL;
+ }
+ reftable_free(add->new_tables);
+ add->new_tables = NULL;
+ add->new_tables_len = 0;
+
+ if (add->lock_file_fd > 0) {
+ close(add->lock_file_fd);
+ add->lock_file_fd = 0;
+ }
+ if (add->lock_file_name.len > 0) {
+ unlink(add->lock_file_name.buf);
+ strbuf_release(&add->lock_file_name);
+ }
+
+ strbuf_release(&nm);
+}
+
+void reftable_addition_destroy(struct reftable_addition *add)
+{
+ if (!add) {
+ return;
+ }
+ reftable_addition_close(add);
+ reftable_free(add);
+}
+
+int reftable_addition_commit(struct reftable_addition *add)
+{
+ struct strbuf table_list = STRBUF_INIT;
+ int i = 0;
+ int err = 0;
+ if (add->new_tables_len == 0)
+ goto done;
+
+ for (i = 0; i < add->stack->merged->stack_len; i++) {
+ strbuf_addstr(&table_list, add->stack->readers[i]->name);
+ strbuf_addstr(&table_list, "\n");
+ }
+ for (i = 0; i < add->new_tables_len; i++) {
+ strbuf_addstr(&table_list, add->new_tables[i]);
+ strbuf_addstr(&table_list, "\n");
+ }
+
+ err = write(add->lock_file_fd, table_list.buf, table_list.len);
+ strbuf_release(&table_list);
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+
+ err = close(add->lock_file_fd);
+ add->lock_file_fd = 0;
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+
+ err = rename(add->lock_file_name.buf, add->stack->list_file);
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+
+ /* success, no more state to clean up. */
+ strbuf_release(&add->lock_file_name);
+ for (i = 0; i < add->new_tables_len; i++) {
+ reftable_free(add->new_tables[i]);
+ }
+ reftable_free(add->new_tables);
+ add->new_tables = NULL;
+ add->new_tables_len = 0;
+
+ err = reftable_stack_reload(add->stack);
+done:
+ reftable_addition_close(add);
+ return err;
+}
+
+int reftable_stack_new_addition(struct reftable_addition **dest,
+ struct reftable_stack *st)
+{
+ int err = 0;
+ struct reftable_addition empty = REFTABLE_ADDITION_INIT;
+ *dest = reftable_calloc(sizeof(**dest));
+ **dest = empty;
+ err = reftable_stack_init_addition(*dest, st);
+ if (err) {
+ reftable_free(*dest);
+ *dest = NULL;
+ }
+ return err;
+}
+
+static int stack_try_add(struct reftable_stack *st,
+ int (*write_table)(struct reftable_writer *wr,
+ void *arg),
+ void *arg)
+{
+ struct reftable_addition add = REFTABLE_ADDITION_INIT;
+ int err = reftable_stack_init_addition(&add, st);
+ if (err < 0)
+ goto done;
+ if (err > 0) {
+ err = REFTABLE_LOCK_ERROR;
+ goto done;
+ }
+
+ err = reftable_addition_add(&add, write_table, arg);
+ if (err < 0)
+ goto done;
+
+ err = reftable_addition_commit(&add);
+done:
+ reftable_addition_close(&add);
+ return err;
+}
+
+int reftable_addition_add(struct reftable_addition *add,
+ int (*write_table)(struct reftable_writer *wr,
+ void *arg),
+ void *arg)
+{
+ struct strbuf temp_tab_file_name = STRBUF_INIT;
+ struct strbuf tab_file_name = STRBUF_INIT;
+ struct strbuf next_name = STRBUF_INIT;
+ struct reftable_writer *wr = NULL;
+ int err = 0;
+ int tab_fd = 0;
+
+ strbuf_reset(&next_name);
+ format_name(&next_name, add->next_update_index, add->next_update_index);
+
+ stack_filename(&temp_tab_file_name, add->stack, next_name.buf);
+ strbuf_addstr(&temp_tab_file_name, ".temp.XXXXXX");
+
+ tab_fd = mkstemp(temp_tab_file_name.buf);
+ if (tab_fd < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+
+ wr = reftable_new_writer(reftable_fd_write, &tab_fd,
+ &add->stack->config);
+ err = write_table(wr, arg);
+ if (err < 0)
+ goto done;
+
+ err = reftable_writer_close(wr);
+ if (err == REFTABLE_EMPTY_TABLE_ERROR) {
+ err = 0;
+ goto done;
+ }
+ if (err < 0)
+ goto done;
+
+ err = close(tab_fd);
+ tab_fd = 0;
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+
+ err = stack_check_addition(add->stack, temp_tab_file_name.buf);
+ if (err < 0)
+ goto done;
+
+ if (wr->min_update_index < add->next_update_index) {
+ err = REFTABLE_API_ERROR;
+ goto done;
+ }
+
+ format_name(&next_name, wr->min_update_index, wr->max_update_index);
+ strbuf_addstr(&next_name, ".ref");
+
+ stack_filename(&tab_file_name, add->stack, next_name.buf);
+
+ /*
+ On windows, this relies on rand() picking a unique destination name.
+ Maybe we should do retry loop as well?
+ */
+ err = rename(temp_tab_file_name.buf, tab_file_name.buf);
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+
+ add->new_tables = reftable_realloc(add->new_tables,
+ sizeof(*add->new_tables) *
+ (add->new_tables_len + 1));
+ add->new_tables[add->new_tables_len] = strbuf_detach(&next_name, NULL);
+ add->new_tables_len++;
+done:
+ if (tab_fd > 0) {
+ close(tab_fd);
+ tab_fd = 0;
+ }
+ if (temp_tab_file_name.len > 0) {
+ unlink(temp_tab_file_name.buf);
+ }
+
+ strbuf_release(&temp_tab_file_name);
+ strbuf_release(&tab_file_name);
+ strbuf_release(&next_name);
+ reftable_writer_free(wr);
+ return err;
+}
+
+uint64_t reftable_stack_next_update_index(struct reftable_stack *st)
+{
+ int sz = st->merged->stack_len;
+ if (sz > 0)
+ return reftable_reader_max_update_index(st->readers[sz - 1]) +
+ 1;
+ return 1;
+}
+
+static int stack_compact_locked(struct reftable_stack *st, int first, int last,
+ struct strbuf *temp_tab,
+ struct reftable_log_expiry_config *config)
+{
+ struct strbuf next_name = STRBUF_INIT;
+ int tab_fd = -1;
+ struct reftable_writer *wr = NULL;
+ int err = 0;
+
+ format_name(&next_name,
+ reftable_reader_min_update_index(st->readers[first]),
+ reftable_reader_max_update_index(st->readers[last]));
+
+ stack_filename(temp_tab, st, next_name.buf);
+ strbuf_addstr(temp_tab, ".temp.XXXXXX");
+
+ tab_fd = mkstemp(temp_tab->buf);
+ wr = reftable_new_writer(reftable_fd_write, &tab_fd, &st->config);
+
+ err = stack_write_compact(st, wr, first, last, config);
+ if (err < 0)
+ goto done;
+ err = reftable_writer_close(wr);
+ if (err < 0)
+ goto done;
+
+ err = close(tab_fd);
+ tab_fd = 0;
+
+done:
+ reftable_writer_free(wr);
+ if (tab_fd > 0) {
+ close(tab_fd);
+ tab_fd = 0;
+ }
+ if (err != 0 && temp_tab->len > 0) {
+ unlink(temp_tab->buf);
+ strbuf_release(temp_tab);
+ }
+ strbuf_release(&next_name);
+ return err;
+}
+
+static int stack_write_compact(struct reftable_stack *st,
+ struct reftable_writer *wr, int first, int last,
+ struct reftable_log_expiry_config *config)
+{
+ int subtabs_len = last - first + 1;
+ struct reftable_table *subtabs = reftable_calloc(
+ sizeof(struct reftable_table) * (last - first + 1));
+ struct reftable_merged_table *mt = NULL;
+ int err = 0;
+ struct reftable_iterator it = { NULL };
+ struct reftable_ref_record ref = { NULL };
+ struct reftable_log_record log = { NULL };
+
+ uint64_t entries = 0;
+
+ int i = 0, j = 0;
+ for (i = first, j = 0; i <= last; i++) {
+ struct reftable_reader *t = st->readers[i];
+ reftable_table_from_reader(&subtabs[j++], t);
+ st->stats.bytes += t->size;
+ }
+ reftable_writer_set_limits(wr, st->readers[first]->min_update_index,
+ st->readers[last]->max_update_index);
+
+ err = reftable_new_merged_table(&mt, subtabs, subtabs_len,
+ st->config.hash_id);
+ if (err < 0) {
+ reftable_free(subtabs);
+ goto done;
+ }
+
+ err = reftable_merged_table_seek_ref(mt, &it, "");
+ if (err < 0)
+ goto done;
+
+ while (1) {
+ err = reftable_iterator_next_ref(&it, &ref);
+ if (err > 0) {
+ err = 0;
+ break;
+ }
+ if (err < 0) {
+ break;
+ }
+
+ if (first == 0 && reftable_ref_record_is_deletion(&ref)) {
+ continue;
+ }
+
+ err = reftable_writer_add_ref(wr, &ref);
+ if (err < 0) {
+ break;
+ }
+ entries++;
+ }
+ reftable_iterator_destroy(&it);
+
+ err = reftable_merged_table_seek_log(mt, &it, "");
+ if (err < 0)
+ goto done;
+
+ while (1) {
+ err = reftable_iterator_next_log(&it, &log);
+ if (err > 0) {
+ err = 0;
+ break;
+ }
+ if (err < 0) {
+ break;
+ }
+ if (first == 0 && reftable_log_record_is_deletion(&log)) {
+ continue;
+ }
+
+ if (config && config->min_update_index > 0 &&
+ log.update_index < config->min_update_index) {
+ continue;
+ }
+
+ if (config && config->time > 0 &&
+ log.update.time < config->time) {
+ continue;
+ }
+
+ err = reftable_writer_add_log(wr, &log);
+ if (err < 0) {
+ break;
+ }
+ entries++;
+ }
+
+done:
+ reftable_iterator_destroy(&it);
+ if (mt) {
+ merged_table_release(mt);
+ reftable_merged_table_free(mt);
+ }
+ reftable_ref_record_release(&ref);
+ reftable_log_record_release(&log);
+ st->stats.entries_written += entries;
+ return err;
+}
+
+/* < 0: error. 0 == OK, > 0 attempt failed; could retry. */
+static int stack_compact_range(struct reftable_stack *st, int first, int last,
+ struct reftable_log_expiry_config *expiry)
+{
+ struct strbuf temp_tab_file_name = STRBUF_INIT;
+ struct strbuf new_table_name = STRBUF_INIT;
+ struct strbuf lock_file_name = STRBUF_INIT;
+ struct strbuf ref_list_contents = STRBUF_INIT;
+ struct strbuf new_table_path = STRBUF_INIT;
+ int err = 0;
+ int have_lock = 0;
+ int lock_file_fd = 0;
+ int compact_count = last - first + 1;
+ char **listp = NULL;
+ char **delete_on_success =
+ reftable_calloc(sizeof(char *) * (compact_count + 1));
+ char **subtable_locks =
+ reftable_calloc(sizeof(char *) * (compact_count + 1));
+ int i = 0;
+ int j = 0;
+ int is_empty_table = 0;
+
+ if (first > last || (!expiry && first == last)) {
+ err = 0;
+ goto done;
+ }
+
+ st->stats.attempts++;
+
+ strbuf_reset(&lock_file_name);
+ strbuf_addstr(&lock_file_name, st->list_file);
+ strbuf_addstr(&lock_file_name, ".lock");
+
+ lock_file_fd =
+ open(lock_file_name.buf, O_EXCL | O_CREAT | O_WRONLY, 0644);
+ if (lock_file_fd < 0) {
+ if (errno == EEXIST) {
+ err = 1;
+ } else {
+ err = REFTABLE_IO_ERROR;
+ }
+ goto done;
+ }
+ /* Don't want to write to the lock for now. */
+ close(lock_file_fd);
+ lock_file_fd = 0;
+
+ have_lock = 1;
+ err = stack_uptodate(st);
+ if (err != 0)
+ goto done;
+
+ for (i = first, j = 0; i <= last; i++) {
+ struct strbuf subtab_file_name = STRBUF_INIT;
+ struct strbuf subtab_lock = STRBUF_INIT;
+ int sublock_file_fd = -1;
+
+ stack_filename(&subtab_file_name, st,
+ reader_name(st->readers[i]));
+
+ strbuf_reset(&subtab_lock);
+ strbuf_addbuf(&subtab_lock, &subtab_file_name);
+ strbuf_addstr(&subtab_lock, ".lock");
+
+ sublock_file_fd = open(subtab_lock.buf,
+ O_EXCL | O_CREAT | O_WRONLY, 0644);
+ if (sublock_file_fd > 0) {
+ close(sublock_file_fd);
+ } else if (sublock_file_fd < 0) {
+ if (errno == EEXIST) {
+ err = 1;
+ } else {
+ err = REFTABLE_IO_ERROR;
+ }
+ }
+
+ subtable_locks[j] = subtab_lock.buf;
+ delete_on_success[j] = subtab_file_name.buf;
+ j++;
+
+ if (err != 0)
+ goto done;
+ }
+
+ err = unlink(lock_file_name.buf);
+ if (err < 0)
+ goto done;
+ have_lock = 0;
+
+ err = stack_compact_locked(st, first, last, &temp_tab_file_name,
+ expiry);
+ /* Compaction + tombstones can create an empty table out of non-empty
+ * tables. */
+ is_empty_table = (err == REFTABLE_EMPTY_TABLE_ERROR);
+ if (is_empty_table) {
+ err = 0;
+ }
+ if (err < 0)
+ goto done;
+
+ lock_file_fd =
+ open(lock_file_name.buf, O_EXCL | O_CREAT | O_WRONLY, 0644);
+ if (lock_file_fd < 0) {
+ if (errno == EEXIST) {
+ err = 1;
+ } else {
+ err = REFTABLE_IO_ERROR;
+ }
+ goto done;
+ }
+ have_lock = 1;
+
+ format_name(&new_table_name, st->readers[first]->min_update_index,
+ st->readers[last]->max_update_index);
+ strbuf_addstr(&new_table_name, ".ref");
+
+ stack_filename(&new_table_path, st, new_table_name.buf);
+
+ if (!is_empty_table) {
+ /* retry? */
+ err = rename(temp_tab_file_name.buf, new_table_path.buf);
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+ }
+
+ for (i = 0; i < first; i++) {
+ strbuf_addstr(&ref_list_contents, st->readers[i]->name);
+ strbuf_addstr(&ref_list_contents, "\n");
+ }
+ if (!is_empty_table) {
+ strbuf_addbuf(&ref_list_contents, &new_table_name);
+ strbuf_addstr(&ref_list_contents, "\n");
+ }
+ for (i = last + 1; i < st->merged->stack_len; i++) {
+ strbuf_addstr(&ref_list_contents, st->readers[i]->name);
+ strbuf_addstr(&ref_list_contents, "\n");
+ }
+
+ err = write(lock_file_fd, ref_list_contents.buf, ref_list_contents.len);
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ unlink(new_table_path.buf);
+ goto done;
+ }
+ err = close(lock_file_fd);
+ lock_file_fd = 0;
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ unlink(new_table_path.buf);
+ goto done;
+ }
+
+ err = rename(lock_file_name.buf, st->list_file);
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ unlink(new_table_path.buf);
+ goto done;
+ }
+ have_lock = 0;
+
+ /* Reload the stack before deleting. On windows, we can only delete the
+ files after we closed them.
+ */
+ err = reftable_stack_reload_maybe_reuse(st, first < last);
+
+ listp = delete_on_success;
+ while (*listp) {
+ if (strcmp(*listp, new_table_path.buf)) {
+ unlink(*listp);
+ }
+ listp++;
+ }
+
+done:
+ free_names(delete_on_success);
+
+ listp = subtable_locks;
+ while (*listp) {
+ unlink(*listp);
+ listp++;
+ }
+ free_names(subtable_locks);
+ if (lock_file_fd > 0) {
+ close(lock_file_fd);
+ lock_file_fd = 0;
+ }
+ if (have_lock) {
+ unlink(lock_file_name.buf);
+ }
+ strbuf_release(&new_table_name);
+ strbuf_release(&new_table_path);
+ strbuf_release(&ref_list_contents);
+ strbuf_release(&temp_tab_file_name);
+ strbuf_release(&lock_file_name);
+ return err;
+}
+
+int reftable_stack_compact_all(struct reftable_stack *st,
+ struct reftable_log_expiry_config *config)
+{
+ return stack_compact_range(st, 0, st->merged->stack_len - 1, config);
+}
+
+static int stack_compact_range_stats(struct reftable_stack *st, int first,
+ int last,
+ struct reftable_log_expiry_config *config)
+{
+ int err = stack_compact_range(st, first, last, config);
+ if (err > 0) {
+ st->stats.failures++;
+ }
+ return err;
+}
+
+static int segment_size(struct segment *s)
+{
+ return s->end - s->start;
+}
+
+int fastlog2(uint64_t sz)
+{
+ int l = 0;
+ if (sz == 0)
+ return 0;
+ for (; sz; sz /= 2) {
+ l++;
+ }
+ return l - 1;
+}
+
+struct segment *sizes_to_segments(int *seglen, uint64_t *sizes, int n)
+{
+ struct segment *segs = reftable_calloc(sizeof(struct segment) * n);
+ int next = 0;
+ struct segment cur = { 0 };
+ int i = 0;
+
+ if (n == 0) {
+ *seglen = 0;
+ return segs;
+ }
+ for (i = 0; i < n; i++) {
+ int log = fastlog2(sizes[i]);
+ if (cur.log != log && cur.bytes > 0) {
+ struct segment fresh = {
+ .start = i,
+ };
+
+ segs[next++] = cur;
+ cur = fresh;
+ }
+
+ cur.log = log;
+ cur.end = i + 1;
+ cur.bytes += sizes[i];
+ }
+ segs[next++] = cur;
+ *seglen = next;
+ return segs;
+}
+
+struct segment suggest_compaction_segment(uint64_t *sizes, int n)
+{
+ int seglen = 0;
+ struct segment *segs = sizes_to_segments(&seglen, sizes, n);
+ struct segment min_seg = {
+ .log = 64,
+ };
+ int i = 0;
+ for (i = 0; i < seglen; i++) {
+ if (segment_size(&segs[i]) == 1) {
+ continue;
+ }
+
+ if (segs[i].log < min_seg.log) {
+ min_seg = segs[i];
+ }
+ }
+
+ while (min_seg.start > 0) {
+ int prev = min_seg.start - 1;
+ if (fastlog2(min_seg.bytes) < fastlog2(sizes[prev])) {
+ break;
+ }
+
+ min_seg.start = prev;
+ min_seg.bytes += sizes[prev];
+ }
+
+ reftable_free(segs);
+ return min_seg;
+}
+
+static uint64_t *stack_table_sizes_for_compaction(struct reftable_stack *st)
+{
+ uint64_t *sizes =
+ reftable_calloc(sizeof(uint64_t) * st->merged->stack_len);
+ int version = (st->config.hash_id == GIT_SHA1_FORMAT_ID) ? 1 : 2;
+ int overhead = header_size(version) - 1;
+ int i = 0;
+ for (i = 0; i < st->merged->stack_len; i++) {
+ sizes[i] = st->readers[i]->size - overhead;
+ }
+ return sizes;
+}
+
+int reftable_stack_auto_compact(struct reftable_stack *st)
+{
+ uint64_t *sizes = stack_table_sizes_for_compaction(st);
+ struct segment seg =
+ suggest_compaction_segment(sizes, st->merged->stack_len);
+ reftable_free(sizes);
+ if (segment_size(&seg) > 0)
+ return stack_compact_range_stats(st, seg.start, seg.end - 1,
+ NULL);
+
+ return 0;
+}
+
+struct reftable_compaction_stats *
+reftable_stack_compaction_stats(struct reftable_stack *st)
+{
+ return &st->stats;
+}
+
+int reftable_stack_read_ref(struct reftable_stack *st, const char *refname,
+ struct reftable_ref_record *ref)
+{
+ struct reftable_table tab = { NULL };
+ reftable_table_from_merged_table(&tab, reftable_stack_merged_table(st));
+ return reftable_table_read_ref(&tab, refname, ref);
+}
+
+int reftable_stack_read_log(struct reftable_stack *st, const char *refname,
+ struct reftable_log_record *log)
+{
+ struct reftable_iterator it = { NULL };
+ struct reftable_merged_table *mt = reftable_stack_merged_table(st);
+ int err = reftable_merged_table_seek_log(mt, &it, refname);
+ if (err)
+ goto done;
+
+ err = reftable_iterator_next_log(&it, log);
+ if (err)
+ goto done;
+
+ if (strcmp(log->refname, refname) ||
+ reftable_log_record_is_deletion(log)) {
+ err = 1;
+ goto done;
+ }
+
+done:
+ if (err) {
+ reftable_log_record_release(log);
+ }
+ reftable_iterator_destroy(&it);
+ return err;
+}
+
+static int stack_check_addition(struct reftable_stack *st,
+ const char *new_tab_name)
+{
+ int err = 0;
+ struct reftable_block_source src = { NULL };
+ struct reftable_reader *rd = NULL;
+ struct reftable_table tab = { NULL };
+ struct reftable_ref_record *refs = NULL;
+ struct reftable_iterator it = { NULL };
+ int cap = 0;
+ int len = 0;
+ int i = 0;
+
+ if (st->config.skip_name_check)
+ return 0;
+
+ err = reftable_block_source_from_file(&src, new_tab_name);
+ if (err < 0)
+ goto done;
+
+ err = reftable_new_reader(&rd, &src, new_tab_name);
+ if (err < 0)
+ goto done;
+
+ err = reftable_reader_seek_ref(rd, &it, "");
+ if (err > 0) {
+ err = 0;
+ goto done;
+ }
+ if (err < 0)
+ goto done;
+
+ while (1) {
+ struct reftable_ref_record ref = { NULL };
+ err = reftable_iterator_next_ref(&it, &ref);
+ if (err > 0) {
+ break;
+ }
+ if (err < 0)
+ goto done;
+
+ if (len >= cap) {
+ cap = 2 * cap + 1;
+ refs = reftable_realloc(refs, cap * sizeof(refs[0]));
+ }
+
+ refs[len++] = ref;
+ }
+
+ reftable_table_from_merged_table(&tab, reftable_stack_merged_table(st));
+
+ err = validate_ref_record_addition(tab, refs, len);
+
+done:
+ for (i = 0; i < len; i++) {
+ reftable_ref_record_release(&refs[i]);
+ }
+
+ free(refs);
+ reftable_iterator_destroy(&it);
+ reftable_reader_free(rd);
+ return err;
+}
+
+static int is_table_name(const char *s)
+{
+ const char *dot = strrchr(s, '.');
+ return dot && !strcmp(dot, ".ref");
+}
+
+static void remove_maybe_stale_table(struct reftable_stack *st, uint64_t max,
+ const char *name)
+{
+ int err = 0;
+ uint64_t update_idx = 0;
+ struct reftable_block_source src = { NULL };
+ struct reftable_reader *rd = NULL;
+ struct strbuf table_path = STRBUF_INIT;
+ stack_filename(&table_path, st, name);
+
+ err = reftable_block_source_from_file(&src, table_path.buf);
+ if (err < 0)
+ goto done;
+
+ err = reftable_new_reader(&rd, &src, name);
+ if (err < 0)
+ goto done;
+
+ update_idx = reftable_reader_max_update_index(rd);
+ reftable_reader_free(rd);
+
+ if (update_idx <= max) {
+ unlink(table_path.buf);
+ }
+done:
+ strbuf_release(&table_path);
+}
+
+static int reftable_stack_clean_locked(struct reftable_stack *st)
+{
+ uint64_t max = reftable_merged_table_max_update_index(
+ reftable_stack_merged_table(st));
+ DIR *dir = opendir(st->reftable_dir);
+ struct dirent *d = NULL;
+ if (!dir) {
+ return REFTABLE_IO_ERROR;
+ }
+
+ while ((d = readdir(dir))) {
+ int i = 0;
+ int found = 0;
+ if (!is_table_name(d->d_name))
+ continue;
+
+ for (i = 0; !found && i < st->readers_len; i++) {
+ found = !strcmp(reader_name(st->readers[i]), d->d_name);
+ }
+ if (found)
+ continue;
+
+ remove_maybe_stale_table(st, max, d->d_name);
+ }
+
+ closedir(dir);
+ return 0;
+}
+
+int reftable_stack_clean(struct reftable_stack *st)
+{
+ struct reftable_addition *add = NULL;
+ int err = reftable_stack_new_addition(&add, st);
+ if (err < 0) {
+ goto done;
+ }
+
+ err = reftable_stack_reload(st);
+ if (err < 0) {
+ goto done;
+ }
+
+ err = reftable_stack_clean_locked(st);
+
+done:
+ reftable_addition_destroy(add);
+ return err;
+}
+
+int reftable_stack_print_directory(const char *stackdir, uint32_t hash_id)
+{
+ struct reftable_stack *stack = NULL;
+ struct reftable_write_options cfg = { .hash_id = hash_id };
+ struct reftable_merged_table *merged = NULL;
+ struct reftable_table table = { NULL };
+
+ int err = reftable_new_stack(&stack, stackdir, cfg);
+ if (err < 0)
+ goto done;
+
+ merged = reftable_stack_merged_table(stack);
+ reftable_table_from_merged_table(&table, merged);
+ err = reftable_table_print(&table);
+done:
+ if (stack)
+ reftable_stack_destroy(stack);
+ return err;
+}
diff --git a/reftable/stack.h b/reftable/stack.h
new file mode 100644
index 0000000..f570058
--- /dev/null
+++ b/reftable/stack.h
@@ -0,0 +1,41 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef STACK_H
+#define STACK_H
+
+#include "system.h"
+#include "reftable-writer.h"
+#include "reftable-stack.h"
+
+struct reftable_stack {
+ char *list_file;
+ char *reftable_dir;
+ int disable_auto_compact;
+
+ struct reftable_write_options config;
+
+ struct reftable_reader **readers;
+ size_t readers_len;
+ struct reftable_merged_table *merged;
+ struct reftable_compaction_stats stats;
+};
+
+int read_lines(const char *filename, char ***lines);
+
+struct segment {
+ int start, end;
+ int log;
+ uint64_t bytes;
+};
+
+int fastlog2(uint64_t sz);
+struct segment *sizes_to_segments(int *seglen, uint64_t *sizes, int n);
+struct segment suggest_compaction_segment(uint64_t *sizes, int n);
+
+#endif
diff --git a/reftable/stack_test.c b/reftable/stack_test.c
new file mode 100644
index 0000000..0743def
--- /dev/null
+++ b/reftable/stack_test.c
@@ -0,0 +1,947 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "stack.h"
+
+#include "system.h"
+
+#include "reftable-reader.h"
+#include "merged.h"
+#include "basics.h"
+#include "constants.h"
+#include "record.h"
+#include "test_framework.h"
+#include "reftable-tests.h"
+
+#include <sys/types.h>
+#include <dirent.h>
+
+static void clear_dir(const char *dirname)
+{
+ struct strbuf path = STRBUF_INIT;
+ strbuf_addstr(&path, dirname);
+ remove_dir_recursively(&path, 0);
+ strbuf_release(&path);
+}
+
+static int count_dir_entries(const char *dirname)
+{
+ DIR *dir = opendir(dirname);
+ int len = 0;
+ struct dirent *d;
+ if (dir == NULL)
+ return 0;
+
+ while ((d = readdir(dir))) {
+ if (!strcmp(d->d_name, "..") || !strcmp(d->d_name, "."))
+ continue;
+ len++;
+ }
+ closedir(dir);
+ return len;
+}
+
+static char *get_tmp_template(const char *prefix)
+{
+ const char *tmp = getenv("TMPDIR");
+ static char template[1024];
+ snprintf(template, sizeof(template) - 1, "%s/%s.XXXXXX",
+ tmp ? tmp : "/tmp", prefix);
+ return template;
+}
+
+static char *get_tmp_dir(const char *prefix)
+{
+ char *dir = get_tmp_template(prefix);
+ EXPECT(mkdtemp(dir));
+ return dir;
+}
+
+static void test_read_file(void)
+{
+ char *fn = get_tmp_template(__FUNCTION__);
+ int fd = mkstemp(fn);
+ char out[1024] = "line1\n\nline2\nline3";
+ int n, err;
+ char **names = NULL;
+ char *want[] = { "line1", "line2", "line3" };
+ int i = 0;
+
+ EXPECT(fd > 0);
+ n = write(fd, out, strlen(out));
+ EXPECT(n == strlen(out));
+ err = close(fd);
+ EXPECT(err >= 0);
+
+ err = read_lines(fn, &names);
+ EXPECT_ERR(err);
+
+ for (i = 0; names[i]; i++) {
+ EXPECT(0 == strcmp(want[i], names[i]));
+ }
+ free_names(names);
+ remove(fn);
+}
+
+static void test_parse_names(void)
+{
+ char buf[] = "line\n";
+ char **names = NULL;
+ parse_names(buf, strlen(buf), &names);
+
+ EXPECT(NULL != names[0]);
+ EXPECT(0 == strcmp(names[0], "line"));
+ EXPECT(NULL == names[1]);
+ free_names(names);
+}
+
+static void test_names_equal(void)
+{
+ char *a[] = { "a", "b", "c", NULL };
+ char *b[] = { "a", "b", "d", NULL };
+ char *c[] = { "a", "b", NULL };
+
+ EXPECT(names_equal(a, a));
+ EXPECT(!names_equal(a, b));
+ EXPECT(!names_equal(a, c));
+}
+
+static int write_test_ref(struct reftable_writer *wr, void *arg)
+{
+ struct reftable_ref_record *ref = arg;
+ reftable_writer_set_limits(wr, ref->update_index, ref->update_index);
+ return reftable_writer_add_ref(wr, ref);
+}
+
+struct write_log_arg {
+ struct reftable_log_record *log;
+ uint64_t update_index;
+};
+
+static int write_test_log(struct reftable_writer *wr, void *arg)
+{
+ struct write_log_arg *wla = arg;
+
+ reftable_writer_set_limits(wr, wla->update_index, wla->update_index);
+ return reftable_writer_add_log(wr, wla->log);
+}
+
+static void test_reftable_stack_add_one(void)
+{
+ char *dir = get_tmp_dir(__FUNCTION__);
+
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ int err;
+ struct reftable_ref_record ref = {
+ .refname = "HEAD",
+ .update_index = 1,
+ .value_type = REFTABLE_REF_SYMREF,
+ .value.symref = "master",
+ };
+ struct reftable_ref_record dest = { NULL };
+
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st, &write_test_ref, &ref);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_read_ref(st, ref.refname, &dest);
+ EXPECT_ERR(err);
+ EXPECT(0 == strcmp("master", dest.value.symref));
+
+ printf("testing print functionality:\n");
+ err = reftable_stack_print_directory(dir, GIT_SHA1_FORMAT_ID);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_print_directory(dir, GIT_SHA256_FORMAT_ID);
+ EXPECT(err == REFTABLE_FORMAT_ERROR);
+
+ reftable_ref_record_release(&dest);
+ reftable_stack_destroy(st);
+ clear_dir(dir);
+}
+
+static void test_reftable_stack_uptodate(void)
+{
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st1 = NULL;
+ struct reftable_stack *st2 = NULL;
+ char *dir = get_tmp_dir(__FUNCTION__);
+
+ int err;
+ struct reftable_ref_record ref1 = {
+ .refname = "HEAD",
+ .update_index = 1,
+ .value_type = REFTABLE_REF_SYMREF,
+ .value.symref = "master",
+ };
+ struct reftable_ref_record ref2 = {
+ .refname = "branch2",
+ .update_index = 2,
+ .value_type = REFTABLE_REF_SYMREF,
+ .value.symref = "master",
+ };
+
+
+ /* simulate multi-process access to the same stack
+ by creating two stacks for the same directory.
+ */
+ err = reftable_new_stack(&st1, dir, cfg);
+ EXPECT_ERR(err);
+
+ err = reftable_new_stack(&st2, dir, cfg);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st1, &write_test_ref, &ref1);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st2, &write_test_ref, &ref2);
+ EXPECT(err == REFTABLE_LOCK_ERROR);
+
+ err = reftable_stack_reload(st2);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st2, &write_test_ref, &ref2);
+ EXPECT_ERR(err);
+ reftable_stack_destroy(st1);
+ reftable_stack_destroy(st2);
+ clear_dir(dir);
+}
+
+static void test_reftable_stack_transaction_api(void)
+{
+ char *dir = get_tmp_dir(__FUNCTION__);
+
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ int err;
+ struct reftable_addition *add = NULL;
+
+ struct reftable_ref_record ref = {
+ .refname = "HEAD",
+ .update_index = 1,
+ .value_type = REFTABLE_REF_SYMREF,
+ .value.symref = "master",
+ };
+ struct reftable_ref_record dest = { NULL };
+
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ reftable_addition_destroy(add);
+
+ err = reftable_stack_new_addition(&add, st);
+ EXPECT_ERR(err);
+
+ err = reftable_addition_add(add, &write_test_ref, &ref);
+ EXPECT_ERR(err);
+
+ err = reftable_addition_commit(add);
+ EXPECT_ERR(err);
+
+ reftable_addition_destroy(add);
+
+ err = reftable_stack_read_ref(st, ref.refname, &dest);
+ EXPECT_ERR(err);
+ EXPECT(REFTABLE_REF_SYMREF == dest.value_type);
+ EXPECT(0 == strcmp("master", dest.value.symref));
+
+ reftable_ref_record_release(&dest);
+ reftable_stack_destroy(st);
+ clear_dir(dir);
+}
+
+static void test_reftable_stack_validate_refname(void)
+{
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ int err;
+ char *dir = get_tmp_dir(__FUNCTION__);
+
+ int i;
+ struct reftable_ref_record ref = {
+ .refname = "a/b",
+ .update_index = 1,
+ .value_type = REFTABLE_REF_SYMREF,
+ .value.symref = "master",
+ };
+ char *additions[] = { "a", "a/b/c" };
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st, &write_test_ref, &ref);
+ EXPECT_ERR(err);
+
+ for (i = 0; i < ARRAY_SIZE(additions); i++) {
+ struct reftable_ref_record ref = {
+ .refname = additions[i],
+ .update_index = 1,
+ .value_type = REFTABLE_REF_SYMREF,
+ .value.symref = "master",
+ };
+
+ err = reftable_stack_add(st, &write_test_ref, &ref);
+ EXPECT(err == REFTABLE_NAME_CONFLICT);
+ }
+
+ reftable_stack_destroy(st);
+ clear_dir(dir);
+}
+
+static int write_error(struct reftable_writer *wr, void *arg)
+{
+ return *((int *)arg);
+}
+
+static void test_reftable_stack_update_index_check(void)
+{
+ char *dir = get_tmp_dir(__FUNCTION__);
+
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ int err;
+ struct reftable_ref_record ref1 = {
+ .refname = "name1",
+ .update_index = 1,
+ .value_type = REFTABLE_REF_SYMREF,
+ .value.symref = "master",
+ };
+ struct reftable_ref_record ref2 = {
+ .refname = "name2",
+ .update_index = 1,
+ .value_type = REFTABLE_REF_SYMREF,
+ .value.symref = "master",
+ };
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st, &write_test_ref, &ref1);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st, &write_test_ref, &ref2);
+ EXPECT(err == REFTABLE_API_ERROR);
+ reftable_stack_destroy(st);
+ clear_dir(dir);
+}
+
+static void test_reftable_stack_lock_failure(void)
+{
+ char *dir = get_tmp_dir(__FUNCTION__);
+
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ int err, i;
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+ for (i = -1; i != REFTABLE_EMPTY_TABLE_ERROR; i--) {
+ err = reftable_stack_add(st, &write_error, &i);
+ EXPECT(err == i);
+ }
+
+ reftable_stack_destroy(st);
+ clear_dir(dir);
+}
+
+static void test_reftable_stack_add(void)
+{
+ int i = 0;
+ int err = 0;
+ struct reftable_write_options cfg = {
+ .exact_log_message = 1,
+ };
+ struct reftable_stack *st = NULL;
+ char *dir = get_tmp_dir(__FUNCTION__);
+
+ struct reftable_ref_record refs[2] = { { NULL } };
+ struct reftable_log_record logs[2] = { { NULL } };
+ int N = ARRAY_SIZE(refs);
+
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+ st->disable_auto_compact = 1;
+
+ for (i = 0; i < N; i++) {
+ char buf[256];
+ snprintf(buf, sizeof(buf), "branch%02d", i);
+ refs[i].refname = xstrdup(buf);
+ refs[i].update_index = i + 1;
+ refs[i].value_type = REFTABLE_REF_VAL1;
+ refs[i].value.val1 = reftable_malloc(GIT_SHA1_RAWSZ);
+ set_test_hash(refs[i].value.val1, i);
+
+ logs[i].refname = xstrdup(buf);
+ logs[i].update_index = N + i + 1;
+ logs[i].value_type = REFTABLE_LOG_UPDATE;
+
+ logs[i].update.new_hash = reftable_malloc(GIT_SHA1_RAWSZ);
+ logs[i].update.email = xstrdup("identity@invalid");
+ set_test_hash(logs[i].update.new_hash, i);
+ }
+
+ for (i = 0; i < N; i++) {
+ int err = reftable_stack_add(st, &write_test_ref, &refs[i]);
+ EXPECT_ERR(err);
+ }
+
+ for (i = 0; i < N; i++) {
+ struct write_log_arg arg = {
+ .log = &logs[i],
+ .update_index = reftable_stack_next_update_index(st),
+ };
+ int err = reftable_stack_add(st, &write_test_log, &arg);
+ EXPECT_ERR(err);
+ }
+
+ err = reftable_stack_compact_all(st, NULL);
+ EXPECT_ERR(err);
+
+ for (i = 0; i < N; i++) {
+ struct reftable_ref_record dest = { NULL };
+
+ int err = reftable_stack_read_ref(st, refs[i].refname, &dest);
+ EXPECT_ERR(err);
+ EXPECT(reftable_ref_record_equal(&dest, refs + i,
+ GIT_SHA1_RAWSZ));
+ reftable_ref_record_release(&dest);
+ }
+
+ for (i = 0; i < N; i++) {
+ struct reftable_log_record dest = { NULL };
+ int err = reftable_stack_read_log(st, refs[i].refname, &dest);
+ EXPECT_ERR(err);
+ EXPECT(reftable_log_record_equal(&dest, logs + i,
+ GIT_SHA1_RAWSZ));
+ reftable_log_record_release(&dest);
+ }
+
+ /* cleanup */
+ reftable_stack_destroy(st);
+ for (i = 0; i < N; i++) {
+ reftable_ref_record_release(&refs[i]);
+ reftable_log_record_release(&logs[i]);
+ }
+ clear_dir(dir);
+}
+
+static void test_reftable_stack_log_normalize(void)
+{
+ int err = 0;
+ struct reftable_write_options cfg = {
+ 0,
+ };
+ struct reftable_stack *st = NULL;
+ char *dir = get_tmp_dir(__FUNCTION__);
+
+
+ uint8_t h1[GIT_SHA1_RAWSZ] = { 0x01 }, h2[GIT_SHA1_RAWSZ] = { 0x02 };
+
+ struct reftable_log_record input = { .refname = "branch",
+ .update_index = 1,
+ .value_type = REFTABLE_LOG_UPDATE,
+ .update = {
+ .new_hash = h1,
+ .old_hash = h2,
+ } };
+ struct reftable_log_record dest = {
+ .update_index = 0,
+ };
+ struct write_log_arg arg = {
+ .log = &input,
+ .update_index = 1,
+ };
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ input.update.message = "one\ntwo";
+ err = reftable_stack_add(st, &write_test_log, &arg);
+ EXPECT(err == REFTABLE_API_ERROR);
+
+ input.update.message = "one";
+ err = reftable_stack_add(st, &write_test_log, &arg);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_read_log(st, input.refname, &dest);
+ EXPECT_ERR(err);
+ EXPECT(0 == strcmp(dest.update.message, "one\n"));
+
+ input.update.message = "two\n";
+ arg.update_index = 2;
+ err = reftable_stack_add(st, &write_test_log, &arg);
+ EXPECT_ERR(err);
+ err = reftable_stack_read_log(st, input.refname, &dest);
+ EXPECT_ERR(err);
+ EXPECT(0 == strcmp(dest.update.message, "two\n"));
+
+ /* cleanup */
+ reftable_stack_destroy(st);
+ reftable_log_record_release(&dest);
+ clear_dir(dir);
+}
+
+static void test_reftable_stack_tombstone(void)
+{
+ int i = 0;
+ char *dir = get_tmp_dir(__FUNCTION__);
+
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ int err;
+ struct reftable_ref_record refs[2] = { { NULL } };
+ struct reftable_log_record logs[2] = { { NULL } };
+ int N = ARRAY_SIZE(refs);
+ struct reftable_ref_record dest = { NULL };
+ struct reftable_log_record log_dest = { NULL };
+
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ /* even entries add the refs, odd entries delete them. */
+ for (i = 0; i < N; i++) {
+ const char *buf = "branch";
+ refs[i].refname = xstrdup(buf);
+ refs[i].update_index = i + 1;
+ if (i % 2 == 0) {
+ refs[i].value_type = REFTABLE_REF_VAL1;
+ refs[i].value.val1 = reftable_malloc(GIT_SHA1_RAWSZ);
+ set_test_hash(refs[i].value.val1, i);
+ }
+
+ logs[i].refname = xstrdup(buf);
+ /* update_index is part of the key. */
+ logs[i].update_index = 42;
+ if (i % 2 == 0) {
+ logs[i].value_type = REFTABLE_LOG_UPDATE;
+ logs[i].update.new_hash =
+ reftable_malloc(GIT_SHA1_RAWSZ);
+ set_test_hash(logs[i].update.new_hash, i);
+ logs[i].update.email = xstrdup("identity@invalid");
+ }
+ }
+ for (i = 0; i < N; i++) {
+ int err = reftable_stack_add(st, &write_test_ref, &refs[i]);
+ EXPECT_ERR(err);
+ }
+
+ for (i = 0; i < N; i++) {
+ struct write_log_arg arg = {
+ .log = &logs[i],
+ .update_index = reftable_stack_next_update_index(st),
+ };
+ int err = reftable_stack_add(st, &write_test_log, &arg);
+ EXPECT_ERR(err);
+ }
+
+ err = reftable_stack_read_ref(st, "branch", &dest);
+ EXPECT(err == 1);
+ reftable_ref_record_release(&dest);
+
+ err = reftable_stack_read_log(st, "branch", &log_dest);
+ EXPECT(err == 1);
+ reftable_log_record_release(&log_dest);
+
+ err = reftable_stack_compact_all(st, NULL);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_read_ref(st, "branch", &dest);
+ EXPECT(err == 1);
+
+ err = reftable_stack_read_log(st, "branch", &log_dest);
+ EXPECT(err == 1);
+ reftable_ref_record_release(&dest);
+ reftable_log_record_release(&log_dest);
+
+ /* cleanup */
+ reftable_stack_destroy(st);
+ for (i = 0; i < N; i++) {
+ reftable_ref_record_release(&refs[i]);
+ reftable_log_record_release(&logs[i]);
+ }
+ clear_dir(dir);
+}
+
+static void test_reftable_stack_hash_id(void)
+{
+ char *dir = get_tmp_dir(__FUNCTION__);
+
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ int err;
+
+ struct reftable_ref_record ref = {
+ .refname = "master",
+ .value_type = REFTABLE_REF_SYMREF,
+ .value.symref = "target",
+ .update_index = 1,
+ };
+ struct reftable_write_options cfg32 = { .hash_id = GIT_SHA256_FORMAT_ID };
+ struct reftable_stack *st32 = NULL;
+ struct reftable_write_options cfg_default = { 0 };
+ struct reftable_stack *st_default = NULL;
+ struct reftable_ref_record dest = { NULL };
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st, &write_test_ref, &ref);
+ EXPECT_ERR(err);
+
+ /* can't read it with the wrong hash ID. */
+ err = reftable_new_stack(&st32, dir, cfg32);
+ EXPECT(err == REFTABLE_FORMAT_ERROR);
+
+ /* check that we can read it back with default config too. */
+ err = reftable_new_stack(&st_default, dir, cfg_default);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_read_ref(st_default, "master", &dest);
+ EXPECT_ERR(err);
+
+ EXPECT(reftable_ref_record_equal(&ref, &dest, GIT_SHA1_RAWSZ));
+ reftable_ref_record_release(&dest);
+ reftable_stack_destroy(st);
+ reftable_stack_destroy(st_default);
+ clear_dir(dir);
+}
+
+static void test_log2(void)
+{
+ EXPECT(1 == fastlog2(3));
+ EXPECT(2 == fastlog2(4));
+ EXPECT(2 == fastlog2(5));
+}
+
+static void test_sizes_to_segments(void)
+{
+ uint64_t sizes[] = { 2, 3, 4, 5, 7, 9 };
+ /* .................0 1 2 3 4 5 */
+
+ int seglen = 0;
+ struct segment *segs =
+ sizes_to_segments(&seglen, sizes, ARRAY_SIZE(sizes));
+ EXPECT(segs[2].log == 3);
+ EXPECT(segs[2].start == 5);
+ EXPECT(segs[2].end == 6);
+
+ EXPECT(segs[1].log == 2);
+ EXPECT(segs[1].start == 2);
+ EXPECT(segs[1].end == 5);
+ reftable_free(segs);
+}
+
+static void test_sizes_to_segments_empty(void)
+{
+ int seglen = 0;
+ struct segment *segs = sizes_to_segments(&seglen, NULL, 0);
+ EXPECT(seglen == 0);
+ reftable_free(segs);
+}
+
+static void test_sizes_to_segments_all_equal(void)
+{
+ uint64_t sizes[] = { 5, 5 };
+
+ int seglen = 0;
+ struct segment *segs =
+ sizes_to_segments(&seglen, sizes, ARRAY_SIZE(sizes));
+ EXPECT(seglen == 1);
+ EXPECT(segs[0].start == 0);
+ EXPECT(segs[0].end == 2);
+ reftable_free(segs);
+}
+
+static void test_suggest_compaction_segment(void)
+{
+ uint64_t sizes[] = { 128, 64, 17, 16, 9, 9, 9, 16, 16 };
+ /* .................0 1 2 3 4 5 6 */
+ struct segment min =
+ suggest_compaction_segment(sizes, ARRAY_SIZE(sizes));
+ EXPECT(min.start == 2);
+ EXPECT(min.end == 7);
+}
+
+static void test_suggest_compaction_segment_nothing(void)
+{
+ uint64_t sizes[] = { 64, 32, 16, 8, 4, 2 };
+ struct segment result =
+ suggest_compaction_segment(sizes, ARRAY_SIZE(sizes));
+ EXPECT(result.start == result.end);
+}
+
+static void test_reflog_expire(void)
+{
+ char *dir = get_tmp_dir(__FUNCTION__);
+
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ struct reftable_log_record logs[20] = { { NULL } };
+ int N = ARRAY_SIZE(logs) - 1;
+ int i = 0;
+ int err;
+ struct reftable_log_expiry_config expiry = {
+ .time = 10,
+ };
+ struct reftable_log_record log = { NULL };
+
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ for (i = 1; i <= N; i++) {
+ char buf[256];
+ snprintf(buf, sizeof(buf), "branch%02d", i);
+
+ logs[i].refname = xstrdup(buf);
+ logs[i].update_index = i;
+ logs[i].value_type = REFTABLE_LOG_UPDATE;
+ logs[i].update.time = i;
+ logs[i].update.new_hash = reftable_malloc(GIT_SHA1_RAWSZ);
+ logs[i].update.email = xstrdup("identity@invalid");
+ set_test_hash(logs[i].update.new_hash, i);
+ }
+
+ for (i = 1; i <= N; i++) {
+ struct write_log_arg arg = {
+ .log = &logs[i],
+ .update_index = reftable_stack_next_update_index(st),
+ };
+ int err = reftable_stack_add(st, &write_test_log, &arg);
+ EXPECT_ERR(err);
+ }
+
+ err = reftable_stack_compact_all(st, NULL);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_compact_all(st, &expiry);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_read_log(st, logs[9].refname, &log);
+ EXPECT(err == 1);
+
+ err = reftable_stack_read_log(st, logs[11].refname, &log);
+ EXPECT_ERR(err);
+
+ expiry.min_update_index = 15;
+ err = reftable_stack_compact_all(st, &expiry);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_read_log(st, logs[14].refname, &log);
+ EXPECT(err == 1);
+
+ err = reftable_stack_read_log(st, logs[16].refname, &log);
+ EXPECT_ERR(err);
+
+ /* cleanup */
+ reftable_stack_destroy(st);
+ for (i = 0; i <= N; i++) {
+ reftable_log_record_release(&logs[i]);
+ }
+ clear_dir(dir);
+ reftable_log_record_release(&log);
+}
+
+static int write_nothing(struct reftable_writer *wr, void *arg)
+{
+ reftable_writer_set_limits(wr, 1, 1);
+ return 0;
+}
+
+static void test_empty_add(void)
+{
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ int err;
+ char *dir = get_tmp_dir(__FUNCTION__);
+
+ struct reftable_stack *st2 = NULL;
+
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st, &write_nothing, NULL);
+ EXPECT_ERR(err);
+
+ err = reftable_new_stack(&st2, dir, cfg);
+ EXPECT_ERR(err);
+ clear_dir(dir);
+ reftable_stack_destroy(st);
+ reftable_stack_destroy(st2);
+}
+
+static void test_reftable_stack_auto_compaction(void)
+{
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ char *dir = get_tmp_dir(__FUNCTION__);
+
+ int err, i;
+ int N = 100;
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ for (i = 0; i < N; i++) {
+ char name[100];
+ struct reftable_ref_record ref = {
+ .refname = name,
+ .update_index = reftable_stack_next_update_index(st),
+ .value_type = REFTABLE_REF_SYMREF,
+ .value.symref = "master",
+ };
+ snprintf(name, sizeof(name), "branch%04d", i);
+
+ err = reftable_stack_add(st, &write_test_ref, &ref);
+ EXPECT_ERR(err);
+
+ EXPECT(i < 3 || st->merged->stack_len < 2 * fastlog2(i));
+ }
+
+ EXPECT(reftable_stack_compaction_stats(st)->entries_written <
+ (uint64_t)(N * fastlog2(N)));
+
+ reftable_stack_destroy(st);
+ clear_dir(dir);
+}
+
+static void test_reftable_stack_compaction_concurrent(void)
+{
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st1 = NULL, *st2 = NULL;
+ char *dir = get_tmp_dir(__FUNCTION__);
+
+ int err, i;
+ int N = 3;
+
+ err = reftable_new_stack(&st1, dir, cfg);
+ EXPECT_ERR(err);
+
+ for (i = 0; i < N; i++) {
+ char name[100];
+ struct reftable_ref_record ref = {
+ .refname = name,
+ .update_index = reftable_stack_next_update_index(st1),
+ .value_type = REFTABLE_REF_SYMREF,
+ .value.symref = "master",
+ };
+ snprintf(name, sizeof(name), "branch%04d", i);
+
+ err = reftable_stack_add(st1, &write_test_ref, &ref);
+ EXPECT_ERR(err);
+ }
+
+ err = reftable_new_stack(&st2, dir, cfg);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_compact_all(st1, NULL);
+ EXPECT_ERR(err);
+
+ reftable_stack_destroy(st1);
+ reftable_stack_destroy(st2);
+
+ EXPECT(count_dir_entries(dir) == 2);
+ clear_dir(dir);
+}
+
+static void unclean_stack_close(struct reftable_stack *st)
+{
+ // break abstraction boundary to simulate unclean shutdown.
+ int i = 0;
+ for (; i < st->readers_len; i++) {
+ reftable_reader_free(st->readers[i]);
+ }
+ st->readers_len = 0;
+ FREE_AND_NULL(st->readers);
+}
+
+static void test_reftable_stack_compaction_concurrent_clean(void)
+{
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st1 = NULL, *st2 = NULL, *st3 = NULL;
+ char *dir = get_tmp_dir(__FUNCTION__);
+
+ int err, i;
+ int N = 3;
+
+ err = reftable_new_stack(&st1, dir, cfg);
+ EXPECT_ERR(err);
+
+ for (i = 0; i < N; i++) {
+ char name[100];
+ struct reftable_ref_record ref = {
+ .refname = name,
+ .update_index = reftable_stack_next_update_index(st1),
+ .value_type = REFTABLE_REF_SYMREF,
+ .value.symref = "master",
+ };
+ snprintf(name, sizeof(name), "branch%04d", i);
+
+ err = reftable_stack_add(st1, &write_test_ref, &ref);
+ EXPECT_ERR(err);
+ }
+
+ err = reftable_new_stack(&st2, dir, cfg);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_compact_all(st1, NULL);
+ EXPECT_ERR(err);
+
+ unclean_stack_close(st1);
+ unclean_stack_close(st2);
+
+ err = reftable_new_stack(&st3, dir, cfg);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_clean(st3);
+ EXPECT_ERR(err);
+ EXPECT(count_dir_entries(dir) == 2);
+
+ reftable_stack_destroy(st1);
+ reftable_stack_destroy(st2);
+ reftable_stack_destroy(st3);
+
+ clear_dir(dir);
+}
+
+int stack_test_main(int argc, const char *argv[])
+{
+ RUN_TEST(test_empty_add);
+ RUN_TEST(test_log2);
+ RUN_TEST(test_names_equal);
+ RUN_TEST(test_parse_names);
+ RUN_TEST(test_read_file);
+ RUN_TEST(test_reflog_expire);
+ RUN_TEST(test_reftable_stack_add);
+ RUN_TEST(test_reftable_stack_add_one);
+ RUN_TEST(test_reftable_stack_auto_compaction);
+ RUN_TEST(test_reftable_stack_compaction_concurrent);
+ RUN_TEST(test_reftable_stack_compaction_concurrent_clean);
+ RUN_TEST(test_reftable_stack_hash_id);
+ RUN_TEST(test_reftable_stack_lock_failure);
+ RUN_TEST(test_reftable_stack_log_normalize);
+ RUN_TEST(test_reftable_stack_tombstone);
+ RUN_TEST(test_reftable_stack_transaction_api);
+ RUN_TEST(test_reftable_stack_update_index_check);
+ RUN_TEST(test_reftable_stack_uptodate);
+ RUN_TEST(test_reftable_stack_validate_refname);
+ RUN_TEST(test_sizes_to_segments);
+ RUN_TEST(test_sizes_to_segments_all_equal);
+ RUN_TEST(test_sizes_to_segments_empty);
+ RUN_TEST(test_suggest_compaction_segment);
+ RUN_TEST(test_suggest_compaction_segment_nothing);
+ return 0;
+}
diff --git a/reftable/system.h b/reftable/system.h
new file mode 100644
index 0000000..bf963ee
--- /dev/null
+++ b/reftable/system.h
@@ -0,0 +1,24 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef SYSTEM_H
+#define SYSTEM_H
+
+// This header glues the reftable library to the rest of Git
+
+#include "git-compat-util.h"
+#include "strbuf.h"
+#include "hash.h" /* hash ID, sizes.*/
+#include "dir.h" /* remove_dir_recursively, for tests.*/
+
+#include <zlib.h>
+
+struct strbuf;
+int hash_size(uint32_t id);
+
+#endif
diff --git a/reftable/test_framework.c b/reftable/test_framework.c
new file mode 100644
index 0000000..84ac972
--- /dev/null
+++ b/reftable/test_framework.c
@@ -0,0 +1,23 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "system.h"
+#include "test_framework.h"
+
+#include "basics.h"
+
+void set_test_hash(uint8_t *p, int i)
+{
+ memset(p, (uint8_t)i, hash_size(GIT_SHA1_FORMAT_ID));
+}
+
+ssize_t strbuf_add_void(void *b, const void *data, size_t sz)
+{
+ strbuf_add(b, data, sz);
+ return sz;
+}
diff --git a/reftable/test_framework.h b/reftable/test_framework.h
new file mode 100644
index 0000000..774cb27
--- /dev/null
+++ b/reftable/test_framework.h
@@ -0,0 +1,53 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef TEST_FRAMEWORK_H
+#define TEST_FRAMEWORK_H
+
+#include "system.h"
+#include "reftable-error.h"
+
+#define EXPECT_ERR(c) \
+ if (c != 0) { \
+ fflush(stderr); \
+ fflush(stdout); \
+ fprintf(stderr, "%s: %d: error == %d (%s), want 0\n", \
+ __FILE__, __LINE__, c, reftable_error_str(c)); \
+ abort(); \
+ }
+
+#define EXPECT_STREQ(a, b) \
+ if (strcmp(a, b)) { \
+ fflush(stderr); \
+ fflush(stdout); \
+ fprintf(stderr, "%s:%d: %s (%s) != %s (%s)\n", __FILE__, \
+ __LINE__, #a, a, #b, b); \
+ abort(); \
+ }
+
+#define EXPECT(c) \
+ if (!(c)) { \
+ fflush(stderr); \
+ fflush(stdout); \
+ fprintf(stderr, "%s: %d: failed assertion %s\n", __FILE__, \
+ __LINE__, #c); \
+ abort(); \
+ }
+
+#define RUN_TEST(f) \
+ fprintf(stderr, "running %s\n", #f); \
+ fflush(stderr); \
+ f();
+
+void set_test_hash(uint8_t *p, int i);
+
+/* Like strbuf_add, but suitable for passing to reftable_new_writer
+ */
+ssize_t strbuf_add_void(void *b, const void *data, size_t sz);
+
+#endif
diff --git a/reftable/tree.c b/reftable/tree.c
new file mode 100644
index 0000000..82db799
--- /dev/null
+++ b/reftable/tree.c
@@ -0,0 +1,63 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "tree.h"
+
+#include "basics.h"
+#include "system.h"
+
+struct tree_node *tree_search(void *key, struct tree_node **rootp,
+ int (*compare)(const void *, const void *),
+ int insert)
+{
+ int res;
+ if (*rootp == NULL) {
+ if (!insert) {
+ return NULL;
+ } else {
+ struct tree_node *n =
+ reftable_calloc(sizeof(struct tree_node));
+ n->key = key;
+ *rootp = n;
+ return *rootp;
+ }
+ }
+
+ res = compare(key, (*rootp)->key);
+ if (res < 0)
+ return tree_search(key, &(*rootp)->left, compare, insert);
+ else if (res > 0)
+ return tree_search(key, &(*rootp)->right, compare, insert);
+ return *rootp;
+}
+
+void infix_walk(struct tree_node *t, void (*action)(void *arg, void *key),
+ void *arg)
+{
+ if (t->left) {
+ infix_walk(t->left, action, arg);
+ }
+ action(arg, t->key);
+ if (t->right) {
+ infix_walk(t->right, action, arg);
+ }
+}
+
+void tree_free(struct tree_node *t)
+{
+ if (t == NULL) {
+ return;
+ }
+ if (t->left) {
+ tree_free(t->left);
+ }
+ if (t->right) {
+ tree_free(t->right);
+ }
+ reftable_free(t);
+}
diff --git a/reftable/tree.h b/reftable/tree.h
new file mode 100644
index 0000000..fbdd002
--- /dev/null
+++ b/reftable/tree.h
@@ -0,0 +1,34 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef TREE_H
+#define TREE_H
+
+/* tree_node is a generic binary search tree. */
+struct tree_node {
+ void *key;
+ struct tree_node *left, *right;
+};
+
+/* looks for `key` in `rootp` using `compare` as comparison function. If insert
+ * is set, insert the key if it's not found. Else, return NULL.
+ */
+struct tree_node *tree_search(void *key, struct tree_node **rootp,
+ int (*compare)(const void *, const void *),
+ int insert);
+
+/* performs an infix walk of the tree. */
+void infix_walk(struct tree_node *t, void (*action)(void *arg, void *key),
+ void *arg);
+
+/*
+ * deallocates the tree nodes recursively. Keys should be deallocated separately
+ * by walking over the tree. */
+void tree_free(struct tree_node *t);
+
+#endif
diff --git a/reftable/tree_test.c b/reftable/tree_test.c
new file mode 100644
index 0000000..09a970e
--- /dev/null
+++ b/reftable/tree_test.c
@@ -0,0 +1,61 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "tree.h"
+
+#include "basics.h"
+#include "record.h"
+#include "test_framework.h"
+#include "reftable-tests.h"
+
+static int test_compare(const void *a, const void *b)
+{
+ return (char *)a - (char *)b;
+}
+
+struct curry {
+ void *last;
+};
+
+static void check_increasing(void *arg, void *key)
+{
+ struct curry *c = arg;
+ if (c->last) {
+ assert(test_compare(c->last, key) < 0);
+ }
+ c->last = key;
+}
+
+static void test_tree(void)
+{
+ struct tree_node *root = NULL;
+
+ void *values[11] = { NULL };
+ struct tree_node *nodes[11] = { NULL };
+ int i = 1;
+ struct curry c = { NULL };
+ do {
+ nodes[i] = tree_search(values + i, &root, &test_compare, 1);
+ i = (i * 7) % 11;
+ } while (i != 1);
+
+ for (i = 1; i < ARRAY_SIZE(nodes); i++) {
+ assert(values + i == nodes[i]->key);
+ assert(nodes[i] ==
+ tree_search(values + i, &root, &test_compare, 0));
+ }
+
+ infix_walk(root, check_increasing, &c);
+ tree_free(root);
+}
+
+int tree_test_main(int argc, const char *argv[])
+{
+ RUN_TEST(test_tree);
+ return 0;
+}
diff --git a/reftable/writer.c b/reftable/writer.c
new file mode 100644
index 0000000..1baad06
--- /dev/null
+++ b/reftable/writer.c
@@ -0,0 +1,690 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "writer.h"
+
+#include "system.h"
+
+#include "block.h"
+#include "constants.h"
+#include "record.h"
+#include "tree.h"
+#include "reftable-error.h"
+
+/* finishes a block, and writes it to storage */
+static int writer_flush_block(struct reftable_writer *w);
+
+/* deallocates memory related to the index */
+static void writer_clear_index(struct reftable_writer *w);
+
+/* finishes writing a 'r' (refs) or 'g' (reflogs) section */
+static int writer_finish_public_section(struct reftable_writer *w);
+
+static struct reftable_block_stats *
+writer_reftable_block_stats(struct reftable_writer *w, uint8_t typ)
+{
+ switch (typ) {
+ case 'r':
+ return &w->stats.ref_stats;
+ case 'o':
+ return &w->stats.obj_stats;
+ case 'i':
+ return &w->stats.idx_stats;
+ case 'g':
+ return &w->stats.log_stats;
+ }
+ abort();
+ return NULL;
+}
+
+/* write data, queuing the padding for the next write. Returns negative for
+ * error. */
+static int padded_write(struct reftable_writer *w, uint8_t *data, size_t len,
+ int padding)
+{
+ int n = 0;
+ if (w->pending_padding > 0) {
+ uint8_t *zeroed = reftable_calloc(w->pending_padding);
+ int n = w->write(w->write_arg, zeroed, w->pending_padding);
+ if (n < 0)
+ return n;
+
+ w->pending_padding = 0;
+ reftable_free(zeroed);
+ }
+
+ w->pending_padding = padding;
+ n = w->write(w->write_arg, data, len);
+ if (n < 0)
+ return n;
+ n += padding;
+ return 0;
+}
+
+static void options_set_defaults(struct reftable_write_options *opts)
+{
+ if (opts->restart_interval == 0) {
+ opts->restart_interval = 16;
+ }
+
+ if (opts->hash_id == 0) {
+ opts->hash_id = GIT_SHA1_FORMAT_ID;
+ }
+ if (opts->block_size == 0) {
+ opts->block_size = DEFAULT_BLOCK_SIZE;
+ }
+}
+
+static int writer_version(struct reftable_writer *w)
+{
+ return (w->opts.hash_id == 0 || w->opts.hash_id == GIT_SHA1_FORMAT_ID) ?
+ 1 :
+ 2;
+}
+
+static int writer_write_header(struct reftable_writer *w, uint8_t *dest)
+{
+ memcpy(dest, "REFT", 4);
+
+ dest[4] = writer_version(w);
+
+ put_be24(dest + 5, w->opts.block_size);
+ put_be64(dest + 8, w->min_update_index);
+ put_be64(dest + 16, w->max_update_index);
+ if (writer_version(w) == 2) {
+ put_be32(dest + 24, w->opts.hash_id);
+ }
+ return header_size(writer_version(w));
+}
+
+static void writer_reinit_block_writer(struct reftable_writer *w, uint8_t typ)
+{
+ int block_start = 0;
+ if (w->next == 0) {
+ block_start = header_size(writer_version(w));
+ }
+
+ strbuf_release(&w->last_key);
+ block_writer_init(&w->block_writer_data, typ, w->block,
+ w->opts.block_size, block_start,
+ hash_size(w->opts.hash_id));
+ w->block_writer = &w->block_writer_data;
+ w->block_writer->restart_interval = w->opts.restart_interval;
+}
+
+static struct strbuf reftable_empty_strbuf = STRBUF_INIT;
+
+struct reftable_writer *
+reftable_new_writer(ssize_t (*writer_func)(void *, const void *, size_t),
+ void *writer_arg, struct reftable_write_options *opts)
+{
+ struct reftable_writer *wp =
+ reftable_calloc(sizeof(struct reftable_writer));
+ strbuf_init(&wp->block_writer_data.last_key, 0);
+ options_set_defaults(opts);
+ if (opts->block_size >= (1 << 24)) {
+ /* TODO - error return? */
+ abort();
+ }
+ wp->last_key = reftable_empty_strbuf;
+ wp->block = reftable_calloc(opts->block_size);
+ wp->write = writer_func;
+ wp->write_arg = writer_arg;
+ wp->opts = *opts;
+ writer_reinit_block_writer(wp, BLOCK_TYPE_REF);
+
+ return wp;
+}
+
+void reftable_writer_set_limits(struct reftable_writer *w, uint64_t min,
+ uint64_t max)
+{
+ w->min_update_index = min;
+ w->max_update_index = max;
+}
+
+void reftable_writer_free(struct reftable_writer *w)
+{
+ reftable_free(w->block);
+ reftable_free(w);
+}
+
+struct obj_index_tree_node {
+ struct strbuf hash;
+ uint64_t *offsets;
+ size_t offset_len;
+ size_t offset_cap;
+};
+
+#define OBJ_INDEX_TREE_NODE_INIT \
+ { \
+ .hash = STRBUF_INIT \
+ }
+
+static int obj_index_tree_node_compare(const void *a, const void *b)
+{
+ return strbuf_cmp(&((const struct obj_index_tree_node *)a)->hash,
+ &((const struct obj_index_tree_node *)b)->hash);
+}
+
+static void writer_index_hash(struct reftable_writer *w, struct strbuf *hash)
+{
+ uint64_t off = w->next;
+
+ struct obj_index_tree_node want = { .hash = *hash };
+
+ struct tree_node *node = tree_search(&want, &w->obj_index_tree,
+ &obj_index_tree_node_compare, 0);
+ struct obj_index_tree_node *key = NULL;
+ if (node == NULL) {
+ struct obj_index_tree_node empty = OBJ_INDEX_TREE_NODE_INIT;
+ key = reftable_malloc(sizeof(struct obj_index_tree_node));
+ *key = empty;
+
+ strbuf_reset(&key->hash);
+ strbuf_addbuf(&key->hash, hash);
+ tree_search((void *)key, &w->obj_index_tree,
+ &obj_index_tree_node_compare, 1);
+ } else {
+ key = node->key;
+ }
+
+ if (key->offset_len > 0 && key->offsets[key->offset_len - 1] == off) {
+ return;
+ }
+
+ if (key->offset_len == key->offset_cap) {
+ key->offset_cap = 2 * key->offset_cap + 1;
+ key->offsets = reftable_realloc(
+ key->offsets, sizeof(uint64_t) * key->offset_cap);
+ }
+
+ key->offsets[key->offset_len++] = off;
+}
+
+static int writer_add_record(struct reftable_writer *w,
+ struct reftable_record *rec)
+{
+ struct strbuf key = STRBUF_INIT;
+ int err = -1;
+ reftable_record_key(rec, &key);
+ if (strbuf_cmp(&w->last_key, &key) >= 0) {
+ err = REFTABLE_API_ERROR;
+ goto done;
+ }
+
+ strbuf_reset(&w->last_key);
+ strbuf_addbuf(&w->last_key, &key);
+ if (w->block_writer == NULL) {
+ writer_reinit_block_writer(w, reftable_record_type(rec));
+ }
+
+ assert(block_writer_type(w->block_writer) == reftable_record_type(rec));
+
+ if (block_writer_add(w->block_writer, rec) == 0) {
+ err = 0;
+ goto done;
+ }
+
+ err = writer_flush_block(w);
+ if (err < 0) {
+ goto done;
+ }
+
+ writer_reinit_block_writer(w, reftable_record_type(rec));
+ err = block_writer_add(w->block_writer, rec);
+ if (err < 0) {
+ goto done;
+ }
+
+ err = 0;
+done:
+ strbuf_release(&key);
+ return err;
+}
+
+int reftable_writer_add_ref(struct reftable_writer *w,
+ struct reftable_ref_record *ref)
+{
+ struct reftable_record rec = { NULL };
+ struct reftable_ref_record copy = *ref;
+ int err = 0;
+
+ if (ref->refname == NULL)
+ return REFTABLE_API_ERROR;
+ if (ref->update_index < w->min_update_index ||
+ ref->update_index > w->max_update_index)
+ return REFTABLE_API_ERROR;
+
+ reftable_record_from_ref(&rec, &copy);
+ copy.update_index -= w->min_update_index;
+
+ err = writer_add_record(w, &rec);
+ if (err < 0)
+ return err;
+
+ if (!w->opts.skip_index_objects && reftable_ref_record_val1(ref)) {
+ struct strbuf h = STRBUF_INIT;
+ strbuf_add(&h, (char *)reftable_ref_record_val1(ref),
+ hash_size(w->opts.hash_id));
+ writer_index_hash(w, &h);
+ strbuf_release(&h);
+ }
+
+ if (!w->opts.skip_index_objects && reftable_ref_record_val2(ref)) {
+ struct strbuf h = STRBUF_INIT;
+ strbuf_add(&h, reftable_ref_record_val2(ref),
+ hash_size(w->opts.hash_id));
+ writer_index_hash(w, &h);
+ strbuf_release(&h);
+ }
+ return 0;
+}
+
+int reftable_writer_add_refs(struct reftable_writer *w,
+ struct reftable_ref_record *refs, int n)
+{
+ int err = 0;
+ int i = 0;
+ QSORT(refs, n, reftable_ref_record_compare_name);
+ for (i = 0; err == 0 && i < n; i++) {
+ err = reftable_writer_add_ref(w, &refs[i]);
+ }
+ return err;
+}
+
+static int reftable_writer_add_log_verbatim(struct reftable_writer *w,
+ struct reftable_log_record *log)
+{
+ struct reftable_record rec = { NULL };
+ if (w->block_writer &&
+ block_writer_type(w->block_writer) == BLOCK_TYPE_REF) {
+ int err = writer_finish_public_section(w);
+ if (err < 0)
+ return err;
+ }
+
+ w->next -= w->pending_padding;
+ w->pending_padding = 0;
+
+ reftable_record_from_log(&rec, log);
+ return writer_add_record(w, &rec);
+}
+
+int reftable_writer_add_log(struct reftable_writer *w,
+ struct reftable_log_record *log)
+{
+ char *input_log_message = NULL;
+ struct strbuf cleaned_message = STRBUF_INIT;
+ int err = 0;
+
+ if (log->value_type == REFTABLE_LOG_DELETION)
+ return reftable_writer_add_log_verbatim(w, log);
+
+ if (log->refname == NULL)
+ return REFTABLE_API_ERROR;
+
+ input_log_message = log->update.message;
+ if (!w->opts.exact_log_message && log->update.message) {
+ strbuf_addstr(&cleaned_message, log->update.message);
+ while (cleaned_message.len &&
+ cleaned_message.buf[cleaned_message.len - 1] == '\n')
+ strbuf_setlen(&cleaned_message,
+ cleaned_message.len - 1);
+ if (strchr(cleaned_message.buf, '\n')) {
+ // multiple lines not allowed.
+ err = REFTABLE_API_ERROR;
+ goto done;
+ }
+ strbuf_addstr(&cleaned_message, "\n");
+ log->update.message = cleaned_message.buf;
+ }
+
+ err = reftable_writer_add_log_verbatim(w, log);
+ log->update.message = input_log_message;
+done:
+ strbuf_release(&cleaned_message);
+ return err;
+}
+
+int reftable_writer_add_logs(struct reftable_writer *w,
+ struct reftable_log_record *logs, int n)
+{
+ int err = 0;
+ int i = 0;
+ QSORT(logs, n, reftable_log_record_compare_key);
+
+ for (i = 0; err == 0 && i < n; i++) {
+ err = reftable_writer_add_log(w, &logs[i]);
+ }
+ return err;
+}
+
+static int writer_finish_section(struct reftable_writer *w)
+{
+ uint8_t typ = block_writer_type(w->block_writer);
+ uint64_t index_start = 0;
+ int max_level = 0;
+ int threshold = w->opts.unpadded ? 1 : 3;
+ int before_blocks = w->stats.idx_stats.blocks;
+ int err = writer_flush_block(w);
+ int i = 0;
+ struct reftable_block_stats *bstats = NULL;
+ if (err < 0)
+ return err;
+
+ while (w->index_len > threshold) {
+ struct reftable_index_record *idx = NULL;
+ int idx_len = 0;
+
+ max_level++;
+ index_start = w->next;
+ writer_reinit_block_writer(w, BLOCK_TYPE_INDEX);
+
+ idx = w->index;
+ idx_len = w->index_len;
+
+ w->index = NULL;
+ w->index_len = 0;
+ w->index_cap = 0;
+ for (i = 0; i < idx_len; i++) {
+ struct reftable_record rec = { NULL };
+ reftable_record_from_index(&rec, idx + i);
+ if (block_writer_add(w->block_writer, &rec) == 0) {
+ continue;
+ }
+
+ err = writer_flush_block(w);
+ if (err < 0)
+ return err;
+
+ writer_reinit_block_writer(w, BLOCK_TYPE_INDEX);
+
+ err = block_writer_add(w->block_writer, &rec);
+ if (err != 0) {
+ /* write into fresh block should always succeed
+ */
+ abort();
+ }
+ }
+ for (i = 0; i < idx_len; i++) {
+ strbuf_release(&idx[i].last_key);
+ }
+ reftable_free(idx);
+ }
+
+ writer_clear_index(w);
+
+ err = writer_flush_block(w);
+ if (err < 0)
+ return err;
+
+ bstats = writer_reftable_block_stats(w, typ);
+ bstats->index_blocks = w->stats.idx_stats.blocks - before_blocks;
+ bstats->index_offset = index_start;
+ bstats->max_index_level = max_level;
+
+ /* Reinit lastKey, as the next section can start with any key. */
+ w->last_key.len = 0;
+
+ return 0;
+}
+
+struct common_prefix_arg {
+ struct strbuf *last;
+ int max;
+};
+
+static void update_common(void *void_arg, void *key)
+{
+ struct common_prefix_arg *arg = void_arg;
+ struct obj_index_tree_node *entry = key;
+ if (arg->last) {
+ int n = common_prefix_size(&entry->hash, arg->last);
+ if (n > arg->max) {
+ arg->max = n;
+ }
+ }
+ arg->last = &entry->hash;
+}
+
+struct write_record_arg {
+ struct reftable_writer *w;
+ int err;
+};
+
+static void write_object_record(void *void_arg, void *key)
+{
+ struct write_record_arg *arg = void_arg;
+ struct obj_index_tree_node *entry = key;
+ struct reftable_obj_record obj_rec = {
+ .hash_prefix = (uint8_t *)entry->hash.buf,
+ .hash_prefix_len = arg->w->stats.object_id_len,
+ .offsets = entry->offsets,
+ .offset_len = entry->offset_len,
+ };
+ struct reftable_record rec = { NULL };
+ if (arg->err < 0)
+ goto done;
+
+ reftable_record_from_obj(&rec, &obj_rec);
+ arg->err = block_writer_add(arg->w->block_writer, &rec);
+ if (arg->err == 0)
+ goto done;
+
+ arg->err = writer_flush_block(arg->w);
+ if (arg->err < 0)
+ goto done;
+
+ writer_reinit_block_writer(arg->w, BLOCK_TYPE_OBJ);
+ arg->err = block_writer_add(arg->w->block_writer, &rec);
+ if (arg->err == 0)
+ goto done;
+ obj_rec.offset_len = 0;
+ arg->err = block_writer_add(arg->w->block_writer, &rec);
+
+ /* Should be able to write into a fresh block. */
+ assert(arg->err == 0);
+
+done:;
+}
+
+static void object_record_free(void *void_arg, void *key)
+{
+ struct obj_index_tree_node *entry = key;
+
+ FREE_AND_NULL(entry->offsets);
+ strbuf_release(&entry->hash);
+ reftable_free(entry);
+}
+
+static int writer_dump_object_index(struct reftable_writer *w)
+{
+ struct write_record_arg closure = { .w = w };
+ struct common_prefix_arg common = { NULL };
+ if (w->obj_index_tree) {
+ infix_walk(w->obj_index_tree, &update_common, &common);
+ }
+ w->stats.object_id_len = common.max + 1;
+
+ writer_reinit_block_writer(w, BLOCK_TYPE_OBJ);
+
+ if (w->obj_index_tree) {
+ infix_walk(w->obj_index_tree, &write_object_record, &closure);
+ }
+
+ if (closure.err < 0)
+ return closure.err;
+ return writer_finish_section(w);
+}
+
+static int writer_finish_public_section(struct reftable_writer *w)
+{
+ uint8_t typ = 0;
+ int err = 0;
+
+ if (w->block_writer == NULL)
+ return 0;
+
+ typ = block_writer_type(w->block_writer);
+ err = writer_finish_section(w);
+ if (err < 0)
+ return err;
+ if (typ == BLOCK_TYPE_REF && !w->opts.skip_index_objects &&
+ w->stats.ref_stats.index_blocks > 0) {
+ err = writer_dump_object_index(w);
+ if (err < 0)
+ return err;
+ }
+
+ if (w->obj_index_tree) {
+ infix_walk(w->obj_index_tree, &object_record_free, NULL);
+ tree_free(w->obj_index_tree);
+ w->obj_index_tree = NULL;
+ }
+
+ w->block_writer = NULL;
+ return 0;
+}
+
+int reftable_writer_close(struct reftable_writer *w)
+{
+ uint8_t footer[72];
+ uint8_t *p = footer;
+ int err = writer_finish_public_section(w);
+ int empty_table = w->next == 0;
+ if (err != 0)
+ goto done;
+ w->pending_padding = 0;
+ if (empty_table) {
+ /* Empty tables need a header anyway. */
+ uint8_t header[28];
+ int n = writer_write_header(w, header);
+ err = padded_write(w, header, n, 0);
+ if (err < 0)
+ goto done;
+ }
+
+ p += writer_write_header(w, footer);
+ put_be64(p, w->stats.ref_stats.index_offset);
+ p += 8;
+ put_be64(p, (w->stats.obj_stats.offset) << 5 | w->stats.object_id_len);
+ p += 8;
+ put_be64(p, w->stats.obj_stats.index_offset);
+ p += 8;
+
+ put_be64(p, w->stats.log_stats.offset);
+ p += 8;
+ put_be64(p, w->stats.log_stats.index_offset);
+ p += 8;
+
+ put_be32(p, crc32(0, footer, p - footer));
+ p += 4;
+
+ err = padded_write(w, footer, footer_size(writer_version(w)), 0);
+ if (err < 0)
+ goto done;
+
+ if (empty_table) {
+ err = REFTABLE_EMPTY_TABLE_ERROR;
+ goto done;
+ }
+
+done:
+ /* free up memory. */
+ block_writer_release(&w->block_writer_data);
+ writer_clear_index(w);
+ strbuf_release(&w->last_key);
+ return err;
+}
+
+static void writer_clear_index(struct reftable_writer *w)
+{
+ int i = 0;
+ for (i = 0; i < w->index_len; i++) {
+ strbuf_release(&w->index[i].last_key);
+ }
+
+ FREE_AND_NULL(w->index);
+ w->index_len = 0;
+ w->index_cap = 0;
+}
+
+static const int debug = 0;
+
+static int writer_flush_nonempty_block(struct reftable_writer *w)
+{
+ uint8_t typ = block_writer_type(w->block_writer);
+ struct reftable_block_stats *bstats =
+ writer_reftable_block_stats(w, typ);
+ uint64_t block_typ_off = (bstats->blocks == 0) ? w->next : 0;
+ int raw_bytes = block_writer_finish(w->block_writer);
+ int padding = 0;
+ int err = 0;
+ struct reftable_index_record ir = { .last_key = STRBUF_INIT };
+ if (raw_bytes < 0)
+ return raw_bytes;
+
+ if (!w->opts.unpadded && typ != BLOCK_TYPE_LOG) {
+ padding = w->opts.block_size - raw_bytes;
+ }
+
+ if (block_typ_off > 0) {
+ bstats->offset = block_typ_off;
+ }
+
+ bstats->entries += w->block_writer->entries;
+ bstats->restarts += w->block_writer->restart_len;
+ bstats->blocks++;
+ w->stats.blocks++;
+
+ if (debug) {
+ fprintf(stderr, "block %c off %" PRIu64 " sz %d (%d)\n", typ,
+ w->next, raw_bytes,
+ get_be24(w->block + w->block_writer->header_off + 1));
+ }
+
+ if (w->next == 0) {
+ writer_write_header(w, w->block);
+ }
+
+ err = padded_write(w, w->block, raw_bytes, padding);
+ if (err < 0)
+ return err;
+
+ if (w->index_cap == w->index_len) {
+ w->index_cap = 2 * w->index_cap + 1;
+ w->index = reftable_realloc(
+ w->index,
+ sizeof(struct reftable_index_record) * w->index_cap);
+ }
+
+ ir.offset = w->next;
+ strbuf_reset(&ir.last_key);
+ strbuf_addbuf(&ir.last_key, &w->block_writer->last_key);
+ w->index[w->index_len] = ir;
+
+ w->index_len++;
+ w->next += padding + raw_bytes;
+ w->block_writer = NULL;
+ return 0;
+}
+
+static int writer_flush_block(struct reftable_writer *w)
+{
+ if (w->block_writer == NULL)
+ return 0;
+ if (w->block_writer->entries == 0)
+ return 0;
+ return writer_flush_nonempty_block(w);
+}
+
+const struct reftable_stats *writer_stats(struct reftable_writer *w)
+{
+ return &w->stats;
+}
diff --git a/reftable/writer.h b/reftable/writer.h
new file mode 100644
index 0000000..09b8867
--- /dev/null
+++ b/reftable/writer.h
@@ -0,0 +1,50 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef WRITER_H
+#define WRITER_H
+
+#include "basics.h"
+#include "block.h"
+#include "tree.h"
+#include "reftable-writer.h"
+
+struct reftable_writer {
+ ssize_t (*write)(void *, const void *, size_t);
+ void *write_arg;
+ int pending_padding;
+ struct strbuf last_key;
+
+ /* offset of next block to write. */
+ uint64_t next;
+ uint64_t min_update_index, max_update_index;
+ struct reftable_write_options opts;
+
+ /* memory buffer for writing */
+ uint8_t *block;
+
+ /* writer for the current section. NULL or points to
+ * block_writer_data */
+ struct block_writer *block_writer;
+
+ struct block_writer block_writer_data;
+
+ /* pending index records for the current section */
+ struct reftable_index_record *index;
+ size_t index_len;
+ size_t index_cap;
+
+ /*
+ * tree for use with tsearch; used to populate the 'o' inverse OID
+ * map */
+ struct tree_node *obj_index_tree;
+
+ struct reftable_stats stats;
+};
+
+#endif
diff --git a/repository.c b/repository.c
index b2bf44c..f1cc8df 100644
--- a/repository.c
+++ b/repository.c
@@ -180,6 +180,8 @@ int repo_init(struct repository *repo,
if (worktree)
repo_set_worktree(repo, worktree);
+ repo->ref_storage_format = xstrdup_or_null(format.ref_storage);
+
clear_repository_format(&format);
return 0;
diff --git a/repository.h b/repository.h
index 18fee0d..9fbecb0 100644
--- a/repository.h
+++ b/repository.h
@@ -93,6 +93,9 @@ struct repository {
*/
struct ref_store *refs_private;
+ /* The format to use for the ref database. */
+ char *ref_storage_format;
+
/*
* Contains path to often used file names.
*/
diff --git a/setup.c b/setup.c
index eb9367c..72d2747 100644
--- a/setup.c
+++ b/setup.c
@@ -498,6 +498,9 @@ static enum extension_result handle_extension(const char *var,
return error("invalid value for 'extensions.objectformat'");
data->hash_algo = format;
return EXTENSION_OK;
+ } else if (!strcmp(ext, "refstorage")) {
+ data->ref_storage = xstrdup(value);
+ return EXTENSION_OK;
}
return EXTENSION_UNKNOWN;
}
@@ -648,6 +651,7 @@ void clear_repository_format(struct repository_format *format)
string_list_clear(&format->v1_only_extensions, 0);
free(format->work_tree);
free(format->partial_clone);
+ free(format->ref_storage);
init_repository_format(format);
}
@@ -1312,6 +1316,8 @@ const char *setup_git_directory_gently(int *nongit_ok)
the_repository->repository_format_partial_clone =
repo_fmt.partial_clone;
repo_fmt.partial_clone = NULL;
+ the_repository->ref_storage_format =
+ xstrdup_or_null(repo_fmt.ref_storage);
}
}
/*
diff --git a/t/helper/test-reftable.c b/t/helper/test-reftable.c
new file mode 100644
index 0000000..26b03d7
--- /dev/null
+++ b/t/helper/test-reftable.c
@@ -0,0 +1,21 @@
+#include "reftable/reftable-tests.h"
+#include "test-tool.h"
+
+int cmd__reftable(int argc, const char **argv)
+{
+ basics_test_main(argc, argv);
+ block_test_main(argc, argv);
+ merged_test_main(argc, argv);
+ pq_test_main(argc, argv);
+ record_test_main(argc, argv);
+ refname_test_main(argc, argv);
+ readwrite_test_main(argc, argv);
+ stack_test_main(argc, argv);
+ tree_test_main(argc, argv);
+ return 0;
+}
+
+int cmd__dump_reftable(int argc, const char **argv)
+{
+ return reftable_dump_main(argc, (char *const *)argv);
+}
diff --git a/t/helper/test-tool.c b/t/helper/test-tool.c
index e71d7b0..eb06d94 100644
--- a/t/helper/test-tool.c
+++ b/t/helper/test-tool.c
@@ -53,7 +53,7 @@ static struct test_cmd cmds[] = {
{ "pcre2-config", cmd__pcre2_config },
{ "pkt-line", cmd__pkt_line },
{ "prio-queue", cmd__prio_queue },
- { "proc-receive", cmd__proc_receive},
+ { "proc-receive", cmd__proc_receive },
{ "progress", cmd__progress },
{ "reach", cmd__reach },
{ "read-cache", cmd__read_cache },
@@ -62,6 +62,8 @@ static struct test_cmd cmds[] = {
{ "read-graph", cmd__read_graph },
{ "read-midx", cmd__read_midx },
{ "ref-store", cmd__ref_store },
+ { "reftable", cmd__reftable },
+ { "dump-reftable", cmd__dump_reftable },
{ "regex", cmd__regex },
{ "repository", cmd__repository },
{ "revision-walking", cmd__revision_walking },
diff --git a/t/helper/test-tool.h b/t/helper/test-tool.h
index eda2100..dd3ecda 100644
--- a/t/helper/test-tool.h
+++ b/t/helper/test-tool.h
@@ -19,6 +19,7 @@ int cmd__dump_cache_tree(int argc, const char **argv);
int cmd__dump_fsmonitor(int argc, const char **argv);
int cmd__dump_split_index(int argc, const char **argv);
int cmd__dump_untracked_cache(int argc, const char **argv);
+int cmd__dump_reftable(int argc, const char **argv);
int cmd__example_decorate(int argc, const char **argv);
int cmd__fast_rebase(int argc, const char **argv);
int cmd__fsmonitor_client(int argc, const char **argv);
@@ -51,6 +52,7 @@ int cmd__read_cache_perf(int argc, const char **argv);
int cmd__read_graph(int argc, const char **argv);
int cmd__read_midx(int argc, const char **argv);
int cmd__ref_store(int argc, const char **argv);
+int cmd__reftable(int argc, const char **argv);
int cmd__regex(int argc, const char **argv);
int cmd__repository(int argc, const char **argv);
int cmd__revision_walking(int argc, const char **argv);
diff --git a/t/t0031-reftable.sh b/t/t0031-reftable.sh
new file mode 100755
index 0000000..f024968
--- /dev/null
+++ b/t/t0031-reftable.sh
@@ -0,0 +1,297 @@
+#!/bin/sh
+#
+# Copyright (c) 2020 Google LLC
+#
+
+test_description='reftable basics'
+
+. ./test-lib.sh
+
+INVALID_SHA1=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
+git_init () {
+ git init -b primary "$@"
+}
+
+initialize () {
+ rm -rf .git &&
+ (GIT_TEST_REFTABLE=1; export GIT_TEST_REFTABLE; git_init) &&
+ mv .git/hooks .git/hooks-disabled
+}
+
+write_script fake_editor <<\EOF
+echo "$MSG" >"$1"
+echo "$MSG" >&2
+EOF
+GIT_EDITOR=./fake_editor
+export GIT_EDITOR
+
+
+test_expect_success 'using reftable' '
+ initialize &&
+ test -d .git/reftable &&
+ test -f .git/reftable/tables.list
+'
+
+test_expect_success 'read existing old OID if REF_HAVE_OLD is not set' '
+ initialize &&
+ test_commit 1st &&
+ test_commit 2nd &&
+ MSG=b4 git notes add &&
+ MSG=b3 git notes edit &&
+ echo b4 >expect &&
+ git notes --ref commits@{1} show >actual &&
+ test_cmp expect actual
+'
+
+test_expect_success 'git reflog delete' '
+ initialize &&
+ test_commit file &&
+ test_commit file2 &&
+ test_commit file3 &&
+ test_commit file4 &&
+ git reflog delete HEAD@{1} &&
+ git reflog > output &&
+ ! grep file3 output
+'
+
+test_expect_success 'branch -D delete nonexistent branch' '
+ initialize &&
+ test_commit file &&
+ test_must_fail git branch -D ../../my-private-file
+'
+
+test_expect_success 'branch copy' '
+ initialize &&
+ test_commit file1 &&
+ test_commit file2 &&
+ git branch src &&
+ git reflog src > expect &&
+ git branch -c src dst &&
+ git reflog dst | sed "s/dst/src/g" > actual &&
+ test_cmp expect actual
+'
+
+test_expect_success 'update-ref on corrupted data' '
+ initialize &&
+ test_commit file1 &&
+ OLD_SHA1=$(git rev-parse HEAD) &&
+ test_commit file2 &&
+ ls -l .git/reftable &&
+ for f in .git/reftable/*.ref
+ do
+ >$f
+ done &&
+ test_must_fail git update-ref refs/heads/main $OLD_SHA1
+'
+
+test_expect_success 'git stash' '
+ initialize &&
+ test_commit file &&
+ touch actual expected &&
+ git -c status.showStash=true status >expected &&
+ echo hoi >> file.t &&
+ git stash push -m stashed &&
+ git stash clear &&
+ git -c status.showStash=true status >actual &&
+ test_cmp expected actual
+'
+
+test_expect_success 'rename branch' '
+ initialize &&
+ git symbolic-ref HEAD refs/heads/before &&
+ test_commit file &&
+ git show-ref | sed s/before/after/g > expected &&
+ git branch -M after &&
+ git show-ref > actual &&
+ test_cmp expected actual
+'
+
+test_expect_success 'SHA256 support, env' '
+ rm -rf .git &&
+ GIT_DEFAULT_HASH=sha256 && export GIT_DEFAULT_HASH &&
+ (GIT_TEST_REFTABLE=1 git_init) &&
+ mv .git/hooks .git/hooks-disabled &&
+ test_commit file
+'
+
+test_expect_success 'SHA256 support, option' '
+ rm -rf .git &&
+ (GIT_TEST_REFTABLE=1 git_init --object-format=sha256) &&
+ mv .git/hooks .git/hooks-disabled &&
+ test_commit file
+'
+
+test_expect_success 'delete ref' '
+ initialize &&
+ test_commit file &&
+ SHA=$(git show-ref -s --verify HEAD) &&
+ test_write_lines "$SHA refs/heads/primary" "$SHA refs/tags/file" >expect &&
+ git show-ref >actual &&
+ ! git update-ref -d refs/tags/file $INVALID_SHA1 &&
+ test_cmp expect actual &&
+ git update-ref -d refs/tags/file $SHA &&
+ test_write_lines "$SHA refs/heads/primary" >expect &&
+ git show-ref >actual &&
+ test_cmp expect actual
+'
+
+
+test_expect_success 'clone calls transaction_initial_commit' '
+ test_commit message1 file1 &&
+ git clone . cloned &&
+ (test -f cloned/file1 || echo "Fixme.")
+'
+
+test_expect_success 'basic operation of reftable storage: commit, show-ref' '
+ initialize &&
+ test_commit file &&
+ test_write_lines refs/heads/primary refs/tags/file >expect &&
+ git show-ref &&
+ git show-ref | cut -f2 -d" " >actual &&
+ test_cmp actual expect
+'
+
+test_expect_success 'reflog, repack' '
+ initialize &&
+ for count in $(test_seq 1 10)
+ do
+ test_commit "number $count" file.t $count number-$count ||
+ return 1
+ done &&
+ git pack-refs &&
+ ls -1 .git/reftable >table-files &&
+ test_line_count = 2 table-files &&
+ git reflog refs/heads/primary >output &&
+ test_line_count = 10 output &&
+ grep "commit (initial): number 1" output &&
+ grep "commit: number 10" output &&
+ git gc &&
+ git reflog refs/heads/primary >output &&
+ test_line_count = 0 output
+'
+
+test_expect_success 'branch switch in reflog output' '
+ initialize &&
+ test_commit file1 &&
+ git checkout -b branch1 &&
+ test_commit file2 &&
+ git checkout -b branch2 &&
+ git switch - &&
+ git rev-parse --symbolic-full-name HEAD >actual &&
+ echo refs/heads/branch1 >expect &&
+ test_cmp actual expect
+'
+
+
+# This matches show-ref's output
+print_ref() {
+ echo "$(git rev-parse "$1") $1"
+}
+
+test_expect_success 'peeled tags are stored' '
+ initialize &&
+ test_commit file &&
+ git tag -m "annotated tag" test_tag HEAD &&
+ {
+ print_ref "refs/heads/primary" &&
+ print_ref "refs/tags/file" &&
+ print_ref "refs/tags/test_tag" &&
+ print_ref "refs/tags/test_tag^{}"
+ } >expect &&
+ git show-ref -d >actual &&
+ test_cmp expect actual
+'
+
+test_expect_success 'show-ref works on fresh repo' '
+ initialize &&
+ rm -rf .git &&
+ (GIT_TEST_REFTABLE=1 git_init) &&
+ >expect &&
+ ! git show-ref >actual &&
+ test_cmp expect actual
+'
+
+test_expect_success 'checkout unborn branch' '
+ initialize &&
+ git checkout -b primary
+'
+
+
+test_expect_success 'dir/file conflict' '
+ initialize &&
+ test_commit file &&
+ ! git branch primary/forbidden
+'
+
+
+test_expect_success 'do not clobber existing repo' '
+ rm -rf .git &&
+ git_init &&
+ cat .git/HEAD >expect &&
+ test_commit file &&
+ (GIT_TEST_REFTABLE=1 git_init || true) &&
+ cat .git/HEAD >actual &&
+ test_cmp expect actual
+'
+
+# cherry-pick uses a pseudo ref.
+test_expect_success 'pseudo refs' '
+ initialize &&
+ test_commit message1 file1 &&
+ test_commit message2 file2 &&
+ git branch source &&
+ git checkout HEAD^ &&
+ test_commit message3 file3 &&
+ git cherry-pick source &&
+ test -f file2
+'
+
+# cherry-pick uses a pseudo ref.
+test_expect_success 'rebase' '
+ initialize &&
+ test_commit message1 file1 &&
+ test_commit message2 file2 &&
+ git branch source &&
+ git checkout HEAD^ &&
+ test_commit message3 file3 &&
+ git rebase source &&
+ test -f file2
+'
+
+test_expect_success 'worktrees' '
+ (GIT_TEST_REFTABLE=1 git_init start) &&
+ (cd start && test_commit file1 && git checkout -b branch1 &&
+ git checkout -b branch2 &&
+ git worktree add ../wt
+ ) &&
+ cd wt &&
+ git checkout branch1 &&
+ git branch
+'
+
+test_expect_success 'worktrees 2' '
+ initialize &&
+ test_commit file1 &&
+ mkdir existing_empty &&
+ git worktree add --detach existing_empty primary
+'
+
+test_expect_success 'FETCH_HEAD' '
+ initialize &&
+ test_commit one &&
+ (git_init sub && cd sub && test_commit two) &&
+ git --git-dir sub/.git rev-parse HEAD >expect &&
+ git fetch sub &&
+ git checkout FETCH_HEAD &&
+ git rev-parse HEAD >actual &&
+ test_cmp expect actual
+'
+
+test_expect_success 'dump reftable' '
+ initialize &&
+ hash_id=$(git config extensions.objectformat) &&
+ test-tool dump-reftable $(test "${hash_id}" = "sha256" && echo "-6") -s .git/reftable
+'
+
+test_done
diff --git a/t/t0032-reftable-unittest.sh b/t/t0032-reftable-unittest.sh
new file mode 100755
index 0000000..0ed1497
--- /dev/null
+++ b/t/t0032-reftable-unittest.sh
@@ -0,0 +1,15 @@
+#!/bin/sh
+#
+# Copyright (c) 2020 Google LLC
+#
+
+test_description='reftable unittests'
+
+. ./test-lib.sh
+
+test_expect_success 'unittests' '
+ TMPDIR=$(pwd) && export TMPDIR &&
+ test-tool reftable
+'
+
+test_done
diff --git a/t/t1301-shared-repo.sh b/t/t1301-shared-repo.sh
index 84bf197..a5755b4 100755
--- a/t/t1301-shared-repo.sh
+++ b/t/t1301-shared-repo.sh
@@ -22,9 +22,10 @@ test_expect_success 'shared = 0400 (faulty permission u-w)' '
)
'
+# TODO(hanwen): for REFTABLE should inspect group-readable of .git/reftable/
for u in 002 022
do
- test_expect_success POSIXPERM "shared=1 does not clear bits preset by umask $u" '
+ test_expect_success REFFILES,POSIXPERM "shared=1 does not clear bits preset by umask $u" '
mkdir sub && (
cd sub &&
umask $u &&
@@ -114,7 +115,8 @@ test_expect_success POSIXPERM 'info/refs respects umask in unshared repo' '
test_cmp expect actual
'
-test_expect_success POSIXPERM 'git reflog expire honors core.sharedRepository' '
+# For reftable, the check on .git/reftable/ is sufficient.
+test_expect_success REFFILES,POSIXPERM 'git reflog expire honors core.sharedRepository' '
umask 077 &&
git config core.sharedRepository group &&
git reflog expire --all &&
@@ -201,7 +203,7 @@ test_expect_success POSIXPERM 're-init respects core.sharedrepository (remote)'
test_cmp expect actual
'
-test_expect_success POSIXPERM 'template can set core.sharedrepository' '
+test_expect_success REFFILES,POSIXPERM 'template can set core.sharedrepository' '
rm -rf child.git &&
umask 0022 &&
git config core.sharedrepository 0666 &&
diff --git a/t/t1401-symbolic-ref.sh b/t/t1401-symbolic-ref.sh
index 132a1b8..1b51013 100755
--- a/t/t1401-symbolic-ref.sh
+++ b/t/t1401-symbolic-ref.sh
@@ -102,9 +102,16 @@ test_expect_success LONG_REF 'we can parse long symbolic ref' '
test_cmp expect actual
'
+if test_have_prereq REFFILES
+then
+ HEAD_LOCK=HEAD.lock
+else
+ HEAD_LOCK=reftable/tables.list.lock
+fi
+
test_expect_success 'symbolic-ref reports failure in exit code' '
- test_when_finished "rm -f .git/HEAD.lock" &&
- >.git/HEAD.lock &&
+ test_when_finished "rm -f .git/$HEAD_LOCK" &&
+ >.git/$HEAD_LOCK &&
test_must_fail git symbolic-ref HEAD refs/heads/whatever
'
diff --git a/t/t1404-update-ref-errors.sh b/t/t1404-update-ref-errors.sh
index b729c1f..811d5bb 100755
--- a/t/t1404-update-ref-errors.sh
+++ b/t/t1404-update-ref-errors.sh
@@ -27,7 +27,9 @@ test_update_rejected () {
fi &&
printf "create $prefix/%s $C\n" $create >input &&
test_must_fail git update-ref --stdin <input 2>output.err &&
- test_i18ngrep -F "$error" output.err &&
+ if test_have_prereq REFFILES ; then
+ test_i18ngrep -F "$error" output.err
+ fi &&
git for-each-ref $prefix >actual &&
test_cmp unchanged actual
}
@@ -101,7 +103,9 @@ df_test() {
printf "%s\n" "delete $delname" "create $addname $D"
fi >commands &&
test_must_fail git update-ref --stdin <commands 2>output.err &&
- test_cmp expected-err output.err &&
+ if test_have_prereq REFFILES ; then
+ test_cmp expected-err output.err
+ fi &&
printf "%s\n" "$C $delref" >expected-refs &&
git for-each-ref --format="%(objectname) %(refname)" $prefix/r >actual-refs &&
test_cmp expected-refs actual-refs
@@ -336,7 +340,9 @@ test_expect_success 'missing old value blocks update' '
EOF
printf "%s\n" "update $prefix/foo $E $D" |
test_must_fail git update-ref --stdin 2>output.err &&
- test_cmp expected output.err
+ if test_have_prereq REFFILES ; then
+ test_cmp expected output.err
+ fi
'
test_expect_success 'incorrect old value blocks update' '
@@ -347,7 +353,9 @@ test_expect_success 'incorrect old value blocks update' '
EOF
printf "%s\n" "update $prefix/foo $E $D" |
test_must_fail git update-ref --stdin 2>output.err &&
- test_cmp expected output.err
+ if test_have_prereq REFFILES ; then
+ test_cmp expected output.err
+ fi
'
test_expect_success 'existing old value blocks create' '
@@ -358,7 +366,9 @@ test_expect_success 'existing old value blocks create' '
EOF
printf "%s\n" "create $prefix/foo $E" |
test_must_fail git update-ref --stdin 2>output.err &&
- test_cmp expected output.err
+ if test_have_prereq REFFILES ; then
+ test_cmp expected output.err
+ fi
'
test_expect_success 'incorrect old value blocks delete' '
@@ -369,7 +379,9 @@ test_expect_success 'incorrect old value blocks delete' '
EOF
printf "%s\n" "delete $prefix/foo $D" |
test_must_fail git update-ref --stdin 2>output.err &&
- test_cmp expected output.err
+ if test_have_prereq REFFILES ; then
+ test_cmp expected output.err
+ fi
'
test_expect_success 'missing old value blocks indirect update' '
@@ -380,7 +392,9 @@ test_expect_success 'missing old value blocks indirect update' '
EOF
printf "%s\n" "update $prefix/symref $E $D" |
test_must_fail git update-ref --stdin 2>output.err &&
- test_cmp expected output.err
+ if test_have_prereq REFFILES ; then
+ test_cmp expected output.err
+ fi
'
test_expect_success 'incorrect old value blocks indirect update' '
@@ -392,7 +406,9 @@ test_expect_success 'incorrect old value blocks indirect update' '
EOF
printf "%s\n" "update $prefix/symref $E $D" |
test_must_fail git update-ref --stdin 2>output.err &&
- test_cmp expected output.err
+ if test_have_prereq REFFILES ; then
+ test_cmp expected output.err
+ fi
'
test_expect_success 'existing old value blocks indirect create' '
@@ -404,7 +420,9 @@ test_expect_success 'existing old value blocks indirect create' '
EOF
printf "%s\n" "create $prefix/symref $E" |
test_must_fail git update-ref --stdin 2>output.err &&
- test_cmp expected output.err
+ if test_have_prereq REFFILES ; then
+ test_cmp expected output.err
+ fi
'
test_expect_success 'incorrect old value blocks indirect delete' '
@@ -416,7 +434,9 @@ test_expect_success 'incorrect old value blocks indirect delete' '
EOF
printf "%s\n" "delete $prefix/symref $D" |
test_must_fail git update-ref --stdin 2>output.err &&
- test_cmp expected output.err
+ if test_have_prereq REFFILES ; then
+ test_cmp expected output.err
+ fi
'
test_expect_success 'missing old value blocks indirect no-deref update' '
@@ -427,7 +447,9 @@ test_expect_success 'missing old value blocks indirect no-deref update' '
EOF
printf "%s\n" "option no-deref" "update $prefix/symref $E $D" |
test_must_fail git update-ref --stdin 2>output.err &&
- test_cmp expected output.err
+ if test_have_prereq REFFILES ; then
+ test_cmp expected output.err
+ fi
'
test_expect_success 'incorrect old value blocks indirect no-deref update' '
@@ -439,7 +461,9 @@ test_expect_success 'incorrect old value blocks indirect no-deref update' '
EOF
printf "%s\n" "option no-deref" "update $prefix/symref $E $D" |
test_must_fail git update-ref --stdin 2>output.err &&
- test_cmp expected output.err
+ if test_have_prereq REFFILES ; then
+ test_cmp expected output.err
+ fi
'
test_expect_success 'existing old value blocks indirect no-deref create' '
@@ -451,7 +475,9 @@ test_expect_success 'existing old value blocks indirect no-deref create' '
EOF
printf "%s\n" "option no-deref" "create $prefix/symref $E" |
test_must_fail git update-ref --stdin 2>output.err &&
- test_cmp expected output.err
+ if test_have_prereq REFFILES ; then
+ test_cmp expected output.err
+ fi
'
test_expect_success 'incorrect old value blocks indirect no-deref delete' '
@@ -463,7 +489,9 @@ test_expect_success 'incorrect old value blocks indirect no-deref delete' '
EOF
printf "%s\n" "option no-deref" "delete $prefix/symref $D" |
test_must_fail git update-ref --stdin 2>output.err &&
- test_cmp expected output.err
+ if test_have_prereq REFFILES ; then
+ test_cmp expected output.err
+ fi
'
test_expect_success REFFILES 'non-empty directory blocks create' '
diff --git a/t/t1409-avoid-packing-refs.sh b/t/t1409-avoid-packing-refs.sh
index be12fb6..cdc21bf 100755
--- a/t/t1409-avoid-packing-refs.sh
+++ b/t/t1409-avoid-packing-refs.sh
@@ -4,6 +4,12 @@ test_description='avoid rewriting packed-refs unnecessarily'
. ./test-lib.sh
+if test_have_prereq !REFFILES
+then
+ skip_all='skipping pack-refs tests; need files backend'
+ test_done
+fi
+
# Add an identifying mark to the packed-refs file header line. This
# shouldn't upset readers, and it should be omitted if the file is
# ever rewritten.
diff --git a/t/t1450-fsck.sh b/t/t1450-fsck.sh
index 7d0d575..e5cb141 100755
--- a/t/t1450-fsck.sh
+++ b/t/t1450-fsck.sh
@@ -8,6 +8,12 @@ test_description='git fsck random collection of tests
. ./test-lib.sh
+if test_have_prereq !REFFILES
+then
+ skip_all='skipping tests; incompatible with reftable'
+ test_done
+fi
+
test_expect_success setup '
git config gc.auto 0 &&
git config i18n.commitencoding ISO-8859-1 &&
diff --git a/t/t2011-checkout-invalid-head.sh b/t/t2011-checkout-invalid-head.sh
index e52022e..a56f7af 100755
--- a/t/t2011-checkout-invalid-head.sh
+++ b/t/t2011-checkout-invalid-head.sh
@@ -22,9 +22,16 @@ test_expect_success 'checkout main from invalid HEAD' '
git checkout main --
'
+if test_have_prereq REFFILES
+then
+ HEAD_LOCK=HEAD.lock
+else
+ HEAD_LOCK=reftable/tables.list.lock
+fi
+
test_expect_success 'checkout notices failure to lock HEAD' '
- test_when_finished "rm -f .git/HEAD.lock" &&
- >.git/HEAD.lock &&
+ test_when_finished "rm -f .git/$HEAD_LOCK" &&
+ >.git/$HEAD_LOCK &&
test_must_fail git checkout -b other
'
diff --git a/t/t3210-pack-refs.sh b/t/t3210-pack-refs.sh
index 577f32d..e523c3d 100755
--- a/t/t3210-pack-refs.sh
+++ b/t/t3210-pack-refs.sh
@@ -14,6 +14,12 @@ export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
. ./test-lib.sh
+if test_have_prereq !REFFILES
+then
+ skip_all='skipping pack-refs tests; requires files ref backend'
+ test_done
+fi
+
test_expect_success 'enable reflogs' '
git config core.logallrefupdates true
'
diff --git a/t/t7004-tag.sh b/t/t7004-tag.sh
index 082be85..1e3779c 100755
--- a/t/t7004-tag.sh
+++ b/t/t7004-tag.sh
@@ -97,7 +97,8 @@ test_expect_success 'creating a tag with --create-reflog should create reflog' '
test_when_finished "git tag -d tag_with_reflog" &&
git tag --create-reflog tag_with_reflog &&
git reflog exists refs/tags/tag_with_reflog &&
- sed -e "s/^.* //" .git/logs/refs/tags/tag_with_reflog >actual &&
+ git reflog --format="format:tag: tagging %h (%s, %cd)%n" \
+ --date=format:%Y-%m-%d refs/tags/tag_with_reflog >actual &&
test_cmp expected actual
'
@@ -108,7 +109,9 @@ test_expect_success 'annotated tag with --create-reflog has correct message' '
test_when_finished "git tag -d tag_with_reflog" &&
git tag -m "annotated tag" --create-reflog tag_with_reflog &&
git reflog exists refs/tags/tag_with_reflog &&
- sed -e "s/^.* //" .git/logs/refs/tags/tag_with_reflog >actual &&
+ git reflog \
+ --format="format:tag: tagging %h (%s, %cd)%n" \
+ --date=format:%Y-%m-%d >actual &&
test_cmp expected actual
'
diff --git a/t/test-lib.sh b/t/test-lib.sh
index cf6193b..4708cb9 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -1518,7 +1518,12 @@ parisc* | hppa*)
;;
esac
-test_set_prereq REFFILES
+if test -n "$GIT_TEST_REFTABLE"
+then
+ test_set_prereq !REFFILES
+else
+ test_set_prereq REFFILES
+fi
( COLUMNS=1 && test $COLUMNS = 1 ) && test_set_prereq COLUMNS_CAN_BE_1
test -z "$NO_PERL" && test_set_prereq PERL