Merge branch 'jc/bigfile'

* jc/bigfile:
  Bigfile: teach "git add" to send a large file straight to a pack
  index_fd(): split into two helper functions
  index_fd(): turn write_object and format_check arguments into one flag

7 files changed, 164 insertions, 31 deletions

diff --git a/builtin/hash-object.c b/builtin/hash-object.c
index b96f46a..33911fd 100644
--- a/builtin/hash-object.c
+++ b/builtin/hash-object.c
@@ -14,8 +14,11 @@ static void hash_fd(int fd, const char *type, int write_object, const char *path
 {
 	struct stat st;
 	unsigned char sha1[20];
+	unsigned flags = (HASH_FORMAT_CHECK |
+			  (write_object ? HASH_WRITE_OBJECT : 0));
+
 	if (fstat(fd, &st) < 0 ||
-	    index_fd(sha1, fd, &st, write_object, type_from_string(type), path, 1))
+	    index_fd(sha1, fd, &st, type_from_string(type), path, flags))
 		die(write_object
 		    ? "Unable to add %s to database"
 		    : "Unable to hash %s", path);
diff --git a/builtin/update-index.c b/builtin/update-index.c
index d7850c6..f14bc90 100644
--- a/builtin/update-index.c
+++ b/builtin/update-index.c
@@ -99,7 +99,8 @@ static int add_one_path(struct cache_entry *old, const char *path, int len, stru
 	fill_stat_cache_info(ce, st);
 	ce->ce_mode = ce_mode_from_stat(old, st->st_mode);
 
-	if (index_path(ce->sha1, path, st, !info_only))
+	if (index_path(ce->sha1, path, st,
+		       info_only ? 0 : HASH_WRITE_OBJECT))
 		return -1;
 	option = allow_add ? ADD_CACHE_OK_TO_ADD : 0;
 	option |= allow_replace ? ADD_CACHE_OK_TO_REPLACE : 0;
diff --git a/cache.h b/cache.h
index 28a921d..009b365 100644
--- a/cache.h
+++ b/cache.h
@@ -518,8 +518,11 @@ struct pathspec {
 extern int init_pathspec(struct pathspec *, const char **);
 extern void free_pathspec(struct pathspec *);
 extern int ce_path_match(const struct cache_entry *ce, const struct pathspec *pathspec);
-extern int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, enum object_type type, const char *path, int format_check);
-extern int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object);
+
+#define HASH_WRITE_OBJECT 1
+#define HASH_FORMAT_CHECK 2
+extern int index_fd(unsigned char *sha1, int fd, struct stat *st, enum object_type type, const char *path, unsigned flags);
+extern int index_path(unsigned char *sha1, const char *path, struct stat *st, unsigned flags);
 extern void fill_stat_cache_info(struct cache_entry *ce, struct stat *st);
 
 #define REFRESH_REALLY		0x0001	/* ignore_valid */
diff --git a/notes-merge.c b/notes-merge.c
index 28046a9..e1aaf43 100644
--- a/notes-merge.c
+++ b/notes-merge.c
@@ -707,7 +707,7 @@ int notes_merge_commit(struct notes_merge_options *o,
 		/* write file as blob, and add to partial_tree */
 		if (stat(ent->name, &st))
 			die_errno("Failed to stat '%s'", ent->name);
-		if (index_path(blob_sha1, ent->name, &st, 1))
+		if (index_path(blob_sha1, ent->name, &st, HASH_WRITE_OBJECT))
 			die("Failed to write blob object from '%s'", ent->name);
 		if (add_note(partial_tree, obj_sha1, blob_sha1, NULL))
 			die("Failed to add resolved note '%s' to notes tree",
diff --git a/read-cache.c b/read-cache.c
index f38471c..4ac9a03 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -92,7 +92,7 @@ static int ce_compare_data(struct cache_entry *ce, struct stat *st)
 
 	if (fd >= 0) {
 		unsigned char sha1[20];
-		if (!index_fd(sha1, fd, st, 0, OBJ_BLOB, ce->name, 0))
+		if (!index_fd(sha1, fd, st, OBJ_BLOB, ce->name, 0))
 			match = hashcmp(sha1, ce->sha1);
 		/* index_fd() closed the file descriptor already */
 	}
@@ -641,7 +641,7 @@ int add_to_index(struct index_state *istate, const char *path, struct stat *st,
 		return 0;
 	}
 	if (!intent_only) {
-		if (index_path(ce->sha1, path, st, 1))
+		if (index_path(ce->sha1, path, st, HASH_WRITE_OBJECT))
 			return error("unable to index file %s", path);
 	} else
 		record_intent_to_add(ce);
diff --git a/sha1_file.c b/sha1_file.c
index 357f9ab..064a330 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -11,6 +11,7 @@
 #include "pack.h"
 #include "blob.h"
 #include "commit.h"
+#include "run-command.h"
 #include "tag.h"
 #include "tree.h"
 #include "tree-walk.h"
@@ -2578,10 +2579,11 @@ static void check_tag(const void *buf, size_t size)
 }
 
 static int index_mem(unsigned char *sha1, void *buf, size_t size,
-		     int write_object, enum object_type type,
-		     const char *path, int format_check)
+		     enum object_type type,
+		     const char *path, unsigned flags)
 {
 	int ret, re_allocated = 0;
+	int write_object = flags & HASH_WRITE_OBJECT;
 
 	if (!type)
 		type = OBJ_BLOB;
@@ -2597,7 +2599,7 @@ static int index_mem(unsigned char *sha1, void *buf, size_t size,
 			re_allocated = 1;
 		}
 	}
-	if (format_check) {
+	if (flags & HASH_FORMAT_CHECK) {
 		if (type == OBJ_TREE)
 			check_tree(buf, size);
 		if (type == OBJ_COMMIT)
@@ -2615,44 +2617,141 @@ static int index_mem(unsigned char *sha1, void *buf, size_t size,
 	return ret;
 }
 
+static int index_pipe(unsigned char *sha1, int fd, enum object_type type,
+		      const char *path, unsigned flags)
+{
+	struct strbuf sbuf = STRBUF_INIT;
+	int ret;
+
+	if (strbuf_read(&sbuf, fd, 4096) >= 0)
+		ret = index_mem(sha1, sbuf.buf, sbuf.len, type,	path, flags);
+	else
+		ret = -1;
+	strbuf_release(&sbuf);
+	return ret;
+}
+
 #define SMALL_FILE_SIZE (32*1024)
 
-int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object,
-	     enum object_type type, const char *path, int format_check)
+static int index_core(unsigned char *sha1, int fd, size_t size,
+		      enum object_type type, const char *path,
+		      unsigned flags)
 {
 	int ret;
-	size_t size = xsize_t(st->st_size);
 
-	if (!S_ISREG(st->st_mode)) {
-		struct strbuf sbuf = STRBUF_INIT;
-		if (strbuf_read(&sbuf, fd, 4096) >= 0)
-			ret = index_mem(sha1, sbuf.buf, sbuf.len, write_object,
-					type, path, format_check);
-		else
-			ret = -1;
-		strbuf_release(&sbuf);
-	} else if (!size) {
-		ret = index_mem(sha1, NULL, size, write_object, type, path,
-				format_check);
+	if (!size) {
+		ret = index_mem(sha1, NULL, size, type, path, flags);
 	} else if (size <= SMALL_FILE_SIZE) {
 		char *buf = xmalloc(size);
 		if (size == read_in_full(fd, buf, size))
-			ret = index_mem(sha1, buf, size, write_object, type,
-					path, format_check);
+			ret = index_mem(sha1, buf, size, type, path, flags);
 		else
 			ret = error("short read %s", strerror(errno));
 		free(buf);
 	} else {
 		void *buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
-		ret = index_mem(sha1, buf, size, write_object, type, path,
-				format_check);
+		ret = index_mem(sha1, buf, size, type, path, flags);
 		munmap(buf, size);
 	}
+	return ret;
+}
+
+/*
+ * This creates one packfile per large blob, because the caller
+ * immediately wants the result sha1, and fast-import can report the
+ * object name via marks mechanism only by closing the created
+ * packfile.
+ *
+ * This also bypasses the usual "convert-to-git" dance, and that is on
+ * purpose. We could write a streaming version of the converting
+ * functions and insert that before feeding the data to fast-import
+ * (or equivalent in-core API described above), but the primary
+ * motivation for trying to stream from the working tree file and to
+ * avoid mmaping it in core is to deal with large binary blobs, and
+ * by definition they do _not_ want to get any conversion.
+ */
+static int index_stream(unsigned char *sha1, int fd, size_t size,
+			enum object_type type, const char *path,
+			unsigned flags)
+{
+	struct child_process fast_import;
+	char export_marks[512];
+	const char *argv[] = { "fast-import", "--quiet", export_marks, NULL };
+	char tmpfile[512];
+	char fast_import_cmd[512];
+	char buf[512];
+	int len, tmpfd;
+
+	strcpy(tmpfile, git_path("hashstream_XXXXXX"));
+	tmpfd = git_mkstemp_mode(tmpfile, 0600);
+	if (tmpfd < 0)
+		die_errno("cannot create tempfile: %s", tmpfile);
+	if (close(tmpfd))
+		die_errno("cannot close tempfile: %s", tmpfile);
+	sprintf(export_marks, "--export-marks=%s", tmpfile);
+
+	memset(&fast_import, 0, sizeof(fast_import));
+	fast_import.in = -1;
+	fast_import.argv = argv;
+	fast_import.git_cmd = 1;
+	if (start_command(&fast_import))
+		die_errno("index-stream: git fast-import failed");
+
+	len = sprintf(fast_import_cmd, "blob\nmark :1\ndata %lu\n",
+		      (unsigned long) size);
+	write_or_whine(fast_import.in, fast_import_cmd, len,
+		       "index-stream: feeding fast-import");
+	while (size) {
+		char buf[10240];
+		size_t sz = size < sizeof(buf) ? size : sizeof(buf);
+		size_t actual;
+
+		actual = read_in_full(fd, buf, sz);
+		if (actual < 0)
+			die_errno("index-stream: reading input");
+		if (write_in_full(fast_import.in, buf, actual) != actual)
+			die_errno("index-stream: feeding fast-import");
+		size -= actual;
+	}
+	if (close(fast_import.in))
+		die_errno("index-stream: closing fast-import");
+	if (finish_command(&fast_import))
+		die_errno("index-stream: finishing fast-import");
+
+	tmpfd = open(tmpfile, O_RDONLY);
+	if (tmpfd < 0)
+		die_errno("index-stream: cannot open fast-import mark");
+	len = read(tmpfd, buf, sizeof(buf));
+	if (len < 0)
+		die_errno("index-stream: reading fast-import mark");
+	if (close(tmpfd) < 0)
+		die_errno("index-stream: closing fast-import mark");
+	if (unlink(tmpfile))
+		die_errno("index-stream: unlinking fast-import mark");
+	if (len != 44 ||
+	    memcmp(":1 ", buf, 3) ||
+	    get_sha1_hex(buf + 3, sha1))
+		die_errno("index-stream: unexpected fast-import mark: <%s>", buf);
+	return 0;
+}
+
+int index_fd(unsigned char *sha1, int fd, struct stat *st,
+	     enum object_type type, const char *path, unsigned flags)
+{
+	int ret;
+	size_t size = xsize_t(st->st_size);
+
+	if (!S_ISREG(st->st_mode))
+		ret = index_pipe(sha1, fd, type, path, flags);
+	else if (size <= big_file_threshold || type != OBJ_BLOB)
+		ret = index_core(sha1, fd, size, type, path, flags);
+	else
+		ret = index_stream(sha1, fd, size, type, path, flags);
 	close(fd);
 	return ret;
 }
 
-int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object)
+int index_path(unsigned char *sha1, const char *path, struct stat *st, unsigned flags)
 {
 	int fd;
 	struct strbuf sb = STRBUF_INIT;
@@ -2663,7 +2762,7 @@ int index_path(unsigned char *sha1, const char *path, struct stat *st, int write
 		if (fd < 0)
 			return error("open(\"%s\"): %s", path,
 				     strerror(errno));
-		if (index_fd(sha1, fd, st, write_object, OBJ_BLOB, path, 0) < 0)
+		if (index_fd(sha1, fd, st, OBJ_BLOB, path, flags) < 0)
 			return error("%s: failed to insert into database",
 				     path);
 		break;
@@ -2673,7 +2772,7 @@ int index_path(unsigned char *sha1, const char *path, struct stat *st, int write
 			return error("readlink(\"%s\"): %s", path,
 			             errstr);
 		}
-		if (!write_object)
+		if (!(flags & HASH_WRITE_OBJECT))
 			hash_sha1_file(sb.buf, sb.len, blob_type, sha1);
 		else if (write_sha1_file(sb.buf, sb.len, blob_type, sha1))
 			return error("%s: failed to insert into database",
diff --git a/t/t1050-large.sh b/t/t1050-large.sh
new file mode 100755
index 0000000..deba111
--- /dev/null
+++ b/t/t1050-large.sh
@@ -0,0 +1,27 @@
+#!/bin/sh
+# Copyright (c) 2011, Google Inc.
+
+test_description='adding and checking out large blobs'
+
+. ./test-lib.sh
+
+test_expect_success setup '
+	git config core.bigfilethreshold 200k &&
+	echo X | dd of=large bs=1k seek=2000
+'
+
+test_expect_success 'add a large file' '
+	git add large &&
+	# make sure we got a packfile and no loose objects
+	test -f .git/objects/pack/pack-*.pack &&
+	test ! -f .git/objects/??/??????????????????????????????????????
+'
+
+test_expect_success 'checkout a large file' '
+	large=$(git rev-parse :large) &&
+	git update-index --add --cacheinfo 100644 $large another &&
+	git checkout another &&
+	cmp large another ;# this must not be test_cmp
+'
+
+test_done