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-rw-r--r--Makefile11
-rw-r--r--build-rev-cache.c56
-rw-r--r--cache.h3
-rw-r--r--receive-pack.c1
-rw-r--r--rev-cache.c320
-rw-r--r--rev-cache.h29
-rw-r--r--server-info.c565
-rw-r--r--show-rev-cache.c18
-rw-r--r--update-server-info.c23
9 files changed, 1025 insertions, 1 deletions
diff --git a/Makefile b/Makefile
index 9d30000..6933ae3 100644
--- a/Makefile
+++ b/Makefile
@@ -50,7 +50,8 @@ PROG= git-update-cache git-diff-files git-init-db git-write-tree \
git-diff-stages git-rev-parse git-patch-id git-pack-objects \
git-unpack-objects git-verify-pack git-receive-pack git-send-pack \
git-prune-packed git-fetch-pack git-upload-pack git-clone-pack \
- git-show-index git-daemon git-var git-peek-remote
+ git-show-index git-daemon git-var git-peek-remote \
+ git-update-server-info git-show-rev-cache git-build-rev-cache
all: $(PROG)
@@ -65,6 +66,9 @@ LIB_FILE=libgit.a
LIB_H=cache.h object.h blob.h tree.h commit.h tag.h delta.h epoch.h csum-file.h \
pack.h pkt-line.h refs.h
+LIB_H += rev-cache.h
+LIB_OBJS += rev-cache.o
+
LIB_H += strbuf.h
LIB_OBJS += strbuf.o
@@ -76,6 +80,7 @@ LIB_OBJS += diff.o diffcore-rename.o diffcore-pickaxe.o diffcore-pathspec.o \
count-delta.o diffcore-break.o diffcore-order.o
LIB_OBJS += gitenv.o
+LIB_OBJS += server-info.o
LIBS = $(LIB_FILE)
LIBS += -lz
@@ -152,6 +157,9 @@ git-prune-packed: prune-packed.c
git-fetch-pack: fetch-pack.c
git-var: var.c
git-peek-remote: peek-remote.c
+git-update-server-info: update-server-info.c
+git-build-rev-cache: build-rev-cache.c
+git-show-rev-cache: show-rev-cache.c
git-http-pull: LIBS += -lcurl
git-rev-list: LIBS += -lssl
@@ -165,6 +173,7 @@ object.o: $(LIB_H)
read-cache.o: $(LIB_H)
sha1_file.o: $(LIB_H)
usage.o: $(LIB_H)
+rev-cache.o: $(LIB_H)
strbuf.o: $(LIB_H)
gitenv.o: $(LIB_H)
entry.o: $(LIB_H)
diff --git a/build-rev-cache.c b/build-rev-cache.c
new file mode 100644
index 0000000..948898b
--- /dev/null
+++ b/build-rev-cache.c
@@ -0,0 +1,56 @@
+#include "refs.h"
+#include "cache.h"
+#include "commit.h"
+#include "rev-cache.h"
+
+static void process_head_list(int verbose)
+{
+ char buf[512];
+
+ while (fgets(buf, sizeof(buf), stdin)) {
+ unsigned char sha1[20];
+ struct commit *commit;
+
+ if (get_sha1_hex(buf, sha1)) {
+ error("ignoring: %s", buf);
+ continue;
+ }
+ if (!(commit = lookup_commit_reference(sha1))) {
+ error("not a commit: %s", sha1_to_hex(sha1));
+ continue;
+ }
+ record_rev_cache(commit->object.sha1, verbose ? stderr : NULL);
+ }
+}
+
+
+static const char *build_rev_cache_usage =
+"git-build-rev-cache <rev-cache-file> < list-of-heads";
+
+int main(int ac, char **av)
+{
+ int verbose = 0;
+ const char *path;
+
+ while (1 < ac && av[1][0] == '-') {
+ if (!strcmp(av[1], "-v"))
+ verbose = 1;
+ else
+ usage(build_rev_cache_usage);
+ ac--; av++;
+ }
+
+ if (ac != 2)
+ usage(build_rev_cache_usage);
+
+ path = av[1];
+
+ /* read existing rev-cache */
+ read_rev_cache(path, NULL, 0);
+
+ process_head_list(verbose);
+
+ /* update the rev-cache database by appending newly found one to it */
+ write_rev_cache(path, path);
+ return 0;
+}
diff --git a/cache.h b/cache.h
index 150e144..d1bdb56 100644
--- a/cache.h
+++ b/cache.h
@@ -308,4 +308,7 @@ extern int find_pack_entry_one(const unsigned char *, struct pack_entry *, struc
extern void *unpack_entry_gently(struct pack_entry *, char *, unsigned long *);
extern void packed_object_info_detail(struct pack_entry *, char *, unsigned long *, unsigned long *, int *, unsigned char *);
+/* Dumb servers support */
+extern int update_server_info(int);
+
#endif /* CACHE_H */
diff --git a/receive-pack.c b/receive-pack.c
index f39703f..d4e82bf 100644
--- a/receive-pack.c
+++ b/receive-pack.c
@@ -110,6 +110,7 @@ static void execute_commands(void)
update(cmd->ref_name, cmd->old_sha1, cmd->new_sha1);
cmd = cmd->next;
}
+ update_server_info(0);
}
static void read_head_info(void)
diff --git a/rev-cache.c b/rev-cache.c
new file mode 100644
index 0000000..ea65274
--- /dev/null
+++ b/rev-cache.c
@@ -0,0 +1,320 @@
+#include "refs.h"
+#include "cache.h"
+#include "rev-cache.h"
+
+struct rev_cache **rev_cache;
+int nr_revs, alloc_revs;
+
+struct rev_list_elem *rle_free;
+
+#define BATCH_SIZE 512
+
+int find_rev_cache(const unsigned char *sha1)
+{
+ int lo = 0, hi = nr_revs;
+ while (lo < hi) {
+ int mi = (lo + hi) / 2;
+ struct rev_cache *ri = rev_cache[mi];
+ int cmp = memcmp(sha1, ri->sha1, 20);
+ if (!cmp)
+ return mi;
+ if (cmp < 0)
+ hi = mi;
+ else
+ lo = mi + 1;
+ }
+ return -lo - 1;
+}
+
+static struct rev_list_elem *alloc_list_elem(void)
+{
+ struct rev_list_elem *rle;
+ if (!rle_free) {
+ int i;
+
+ rle = xmalloc(sizeof(*rle) * BATCH_SIZE);
+ for (i = 0; i < BATCH_SIZE - 1; i++) {
+ rle[i].ri = NULL;
+ rle[i].next = &rle[i + 1];
+ }
+ rle[BATCH_SIZE - 1].ri = NULL;
+ rle[BATCH_SIZE - 1].next = NULL;
+ rle_free = rle;
+ }
+ rle = rle_free;
+ rle_free = rle->next;
+ return rle;
+}
+
+static struct rev_cache *create_rev_cache(const unsigned char *sha1)
+{
+ struct rev_cache *ri;
+ int pos = find_rev_cache(sha1);
+
+ if (0 <= pos)
+ return rev_cache[pos];
+ pos = -pos - 1;
+ if (alloc_revs <= ++nr_revs) {
+ alloc_revs = alloc_nr(alloc_revs);
+ rev_cache = xrealloc(rev_cache, sizeof(ri) * alloc_revs);
+ }
+ if (pos < nr_revs)
+ memmove(rev_cache + pos + 1, rev_cache + pos,
+ (nr_revs - pos - 1) * sizeof(ri));
+ ri = xcalloc(1, sizeof(*ri));
+ memcpy(ri->sha1, sha1, 20);
+ rev_cache[pos] = ri;
+ return ri;
+}
+
+static unsigned char last_sha1[20];
+
+static void write_one_rev_cache(FILE *rev_cache_file, struct rev_cache *ri)
+{
+ unsigned char flag;
+ struct rev_list_elem *rle;
+
+ if (ri->written)
+ return;
+
+ if (ri->parsed) {
+ /* We use last_sha1 compression only for the first parent;
+ * otherwise the resulting rev-cache would lose the parent
+ * order information.
+ */
+ if (ri->parents &&
+ !memcmp(ri->parents->ri->sha1, last_sha1, 20))
+ flag = (ri->num_parents - 1) | 0x80;
+ else
+ flag = ri->num_parents;
+
+ fwrite(ri->sha1, 20, 1, rev_cache_file);
+ fwrite(&flag, 1, 1, rev_cache_file);
+ for (rle = ri->parents; rle; rle = rle->next) {
+ if (flag & 0x80 && rle == ri->parents)
+ continue;
+ fwrite(rle->ri->sha1, 20, 1, rev_cache_file);
+ }
+ memcpy(last_sha1, ri->sha1, 20);
+ ri->written = 1;
+ }
+ /* recursively write children depth first */
+ for (rle = ri->children; rle; rle = rle->next)
+ write_one_rev_cache(rev_cache_file, rle->ri);
+}
+
+void write_rev_cache(const char *newpath, const char *oldpath)
+{
+ /* write the following commit ancestry information in
+ * $GIT_DIR/info/rev-cache.
+ *
+ * The format is:
+ * 20-byte SHA1 (commit ID)
+ * 1-byte flag:
+ * - bit 0-6 records "number of parent commit SHA1s to
+ * follow" (i.e. up to 127 children can be listed).
+ * - when the bit 7 is on, then "the entry immediately
+ * before this entry is one of the parents of this
+ * commit".
+ * N x 20-byte SHA1 (parent commit IDs)
+ */
+ FILE *rev_cache_file;
+ int i;
+ struct rev_cache *ri;
+
+ if (!strcmp(newpath, oldpath)) {
+ /* If we are doing it in place */
+ rev_cache_file = fopen(newpath, "a");
+ }
+ else {
+ char buf[8096];
+ size_t sz;
+ FILE *oldfp = fopen(oldpath, "r");
+ rev_cache_file = fopen(newpath, "w");
+ if (oldfp) {
+ while (1) {
+ sz = fread(buf, 1, sizeof(buf), oldfp);
+ if (sz == 0)
+ break;
+ fwrite(buf, 1, sz, rev_cache_file);
+ }
+ fclose(oldfp);
+ }
+ }
+
+ memset(last_sha1, 0, 20);
+
+ /* Go through available rev_cache structures, starting from
+ * parentless ones first, so that we would get most out of
+ * last_sha1 optimization by the depth first behaviour of
+ * write_one_rev_cache().
+ */
+ for (i = 0; i < nr_revs; i++) {
+ ri = rev_cache[i];
+ if (ri->num_parents)
+ continue;
+ write_one_rev_cache(rev_cache_file, ri);
+ }
+ /* Then the rest */
+ for (i = 0; i < nr_revs; i++) {
+ ri = rev_cache[i];
+ write_one_rev_cache(rev_cache_file, ri);
+ }
+ fclose(rev_cache_file);
+}
+
+static void add_parent(struct rev_cache *child,
+ const unsigned char *parent_sha1)
+{
+ struct rev_cache *parent = create_rev_cache(parent_sha1);
+ struct rev_list_elem *e = alloc_list_elem();
+
+ /* Keep the parent list ordered in the same way the commit
+ * object records them.
+ */
+ e->ri = parent;
+ e->next = NULL;
+ if (!child->parents_tail)
+ child->parents = e;
+ else
+ child->parents_tail->next = e;
+ child->parents_tail = e;
+ child->num_parents++;
+
+ /* There is no inherent order of the children so we just
+ * LIFO them together.
+ */
+ e = alloc_list_elem();
+ e->next = parent->children;
+ parent->children = e;
+ e->ri = child;
+ parent->num_children++;
+}
+
+int read_rev_cache(const char *path, FILE *dumpfile, int dry_run)
+{
+ unsigned char *map;
+ int fd;
+ struct stat st;
+ unsigned long ofs, len;
+ struct rev_cache *ri = NULL;
+
+ fd = open(path, O_RDONLY);
+ if (fd < 0) {
+ if (dry_run)
+ return error("cannot open %s", path);
+ if (errno == ENOENT)
+ return 0;
+ return -1;
+ }
+ if (fstat(fd, &st)) {
+ close(fd);
+ return -1;
+ }
+ map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+ if (map == MAP_FAILED) {
+ close(fd);
+ return -1;
+ }
+ close(fd);
+
+ memset(last_sha1, 0, 20);
+ ofs = 0;
+ len = st.st_size;
+ while (ofs < len) {
+ unsigned char sha1[20];
+ int flag, cnt, i;
+ if (len < ofs + 21)
+ die("rev-cache too short");
+ memcpy(sha1, map + ofs, 20);
+ flag = map[ofs + 20];
+ ofs += 21;
+ cnt = (flag & 0x7f) + ((flag & 0x80) != 0);
+ if (len < ofs + (flag & 0x7f) * 20)
+ die("rev-cache too short to have %d more parents",
+ (flag & 0x7f));
+ if (dumpfile)
+ fprintf(dumpfile, "%s", sha1_to_hex(sha1));
+ if (!dry_run) {
+ ri = create_rev_cache(sha1);
+ if (!ri)
+ die("cannot create rev-cache for %s",
+ sha1_to_hex(sha1));
+ ri->written = ri->parsed = 1;
+ }
+ i = 0;
+ if (flag & 0x80) {
+ if (!dry_run)
+ add_parent(ri, last_sha1);
+ if (dumpfile)
+ fprintf(dumpfile, " %s",
+ sha1_to_hex(last_sha1));
+ i++;
+ }
+ while (i++ < cnt) {
+ if (!dry_run)
+ add_parent(ri, map + ofs);
+ if (dumpfile)
+ fprintf(dumpfile, " %s",
+ sha1_to_hex(last_sha1));
+ ofs += 20;
+ }
+ if (dumpfile)
+ fprintf(dumpfile, "\n");
+ memcpy(last_sha1, sha1, 20);
+ }
+ if (ofs != len)
+ die("rev-cache truncated?");
+ munmap(map, len);
+ return 0;
+}
+
+int record_rev_cache(const unsigned char *sha1, FILE *dumpfile)
+{
+ unsigned char parent[20];
+ char type[20];
+ unsigned long size, ofs;
+ unsigned int cnt, i;
+ void *buf;
+ struct rev_cache *ri;
+
+ buf = read_sha1_file(sha1, type, &size);
+ if (!buf)
+ return error("%s: not found", sha1_to_hex(sha1));
+ if (strcmp(type, "commit")) {
+ free(buf);
+ return error("%s: not a commit but a %s",
+ sha1_to_hex(sha1), type);
+ }
+ ri = create_rev_cache(sha1);
+ if (ri->parsed)
+ return 0;
+ if (dumpfile)
+ fprintf(dumpfile, "commit %s\n", sha1_to_hex(sha1));
+
+ cnt = 0;
+ ofs = 46; /* "tree " + hex-sha1 + "\n" */
+ while (!memcmp(buf + ofs, "parent ", 7) &&
+ !get_sha1_hex(buf + ofs + 7, parent)) {
+ ofs += 48;
+ cnt++;
+ }
+ if (cnt * 48 + 46 != ofs) {
+ free(buf);
+ die("internal error in record_rev_cache");
+ }
+
+ ri = create_rev_cache(sha1);
+ ri->parsed = 1;
+
+ for (i = 0; i < cnt; i++) {
+ unsigned char parent_sha1[20];
+
+ ofs = 46 + i * 48 + 7;
+ get_sha1_hex(buf + ofs, parent_sha1);
+ add_parent(ri, parent_sha1);
+ record_rev_cache(parent_sha1, dumpfile);
+ }
+ free(buf);
+ return 0;
+}
diff --git a/rev-cache.h b/rev-cache.h
new file mode 100644
index 0000000..b238ac6
--- /dev/null
+++ b/rev-cache.h
@@ -0,0 +1,29 @@
+#ifndef REV_CACHE_H
+#define REV_CACHE_H
+
+extern struct rev_cache {
+ struct rev_cache *head_list;
+ struct rev_list_elem *children;
+ struct rev_list_elem *parents;
+ struct rev_list_elem *parents_tail;
+ unsigned short num_parents;
+ unsigned short num_children;
+ unsigned int written : 1;
+ unsigned int parsed : 1;
+ unsigned int work : 30;
+ void *work_ptr;
+ unsigned char sha1[20];
+} **rev_cache;
+extern int nr_revs, alloc_revs;
+
+struct rev_list_elem {
+ struct rev_list_elem *next;
+ struct rev_cache *ri;
+};
+
+extern int find_rev_cache(const unsigned char *);
+extern int read_rev_cache(const char *, FILE *, int);
+extern int record_rev_cache(const unsigned char *, FILE *);
+extern void write_rev_cache(const char *new, const char *old);
+
+#endif
diff --git a/server-info.c b/server-info.c
new file mode 100644
index 0000000..00f8ca0
--- /dev/null
+++ b/server-info.c
@@ -0,0 +1,565 @@
+#include "cache.h"
+#include "refs.h"
+#include "object.h"
+#include "commit.h"
+#include "rev-cache.h"
+
+/* refs */
+static FILE *info_ref_fp;
+static unsigned long info_ref_time;
+static int info_ref_is_stale = 0;
+
+static int stat_ref(const char *path, const unsigned char *sha1)
+{
+ struct stat st;
+ if (!stat(path, &st) && info_ref_time < st.st_mtime)
+ info_ref_is_stale = 1;
+ return 0;
+}
+
+static int add_info_ref(const char *path, const unsigned char *sha1)
+{
+ fprintf(info_ref_fp, "%s %s\n", sha1_to_hex(sha1), path);
+ return 0;
+}
+
+static int update_info_refs(int force)
+{
+ struct stat st;
+ char *path0 = strdup(git_path("info/refs"));
+ int len = strlen(path0);
+ char *path1 = xmalloc(len + 2);
+
+ strcpy(path1, path0);
+ strcpy(path1 + len, "+");
+
+ if (!force) {
+ if (stat(path0, &st)) {
+ if (errno == ENOENT)
+ info_ref_is_stale = 1;
+ else
+ return error("cannot stat %s", path0);
+ }
+ else {
+ info_ref_time = st.st_mtime;
+ for_each_ref(stat_ref);
+ }
+ if (!info_ref_is_stale)
+ return 0;
+ }
+
+ safe_create_leading_directories(path0);
+ info_ref_fp = fopen(path1, "w");
+ if (!info_ref_fp)
+ return error("unable to update %s", path0);
+ for_each_ref(add_info_ref);
+ fclose(info_ref_fp);
+ rename(path1, path0);
+ free(path0);
+ free(path1);
+ return 0;
+}
+
+/* packs */
+struct pack_info {
+ unsigned long latest;
+ struct packed_git *p;
+ int old_num;
+ int new_num;
+ int nr_alloc;
+ int nr_heads;
+ unsigned char (*head)[20];
+ char dep[0]; /* more */
+} **info;
+static int num_pack;
+static const char *objdir;
+static int objdirlen;
+
+static struct object *parse_object_cheap(const unsigned char *sha1)
+{
+ struct object *o;
+
+ if ((o = parse_object(sha1)) == NULL)
+ return NULL;
+ if (o->type == commit_type) {
+ struct commit *commit = (struct commit *)o;
+ free(commit->buffer);
+ commit->buffer = NULL;
+ }
+ return o;
+}
+
+static struct pack_info *find_pack_by_name(const char *name)
+{
+ int i;
+ for (i = 0; i < num_pack; i++) {
+ struct packed_git *p = info[i]->p;
+ /* skip "/pack/" after ".git/objects" */
+ if (!strcmp(p->pack_name + objdirlen + 6, name))
+ return info[i];
+ }
+ return NULL;
+}
+
+static struct pack_info *find_pack_by_old_num(int old_num)
+{
+ int i;
+ for (i = 0; i < num_pack; i++)
+ if (info[i]->old_num == old_num)
+ return info[i];
+ return NULL;
+}
+
+static int add_head_def(struct pack_info *this, unsigned char *sha1)
+{
+ if (this->nr_alloc <= this->nr_heads) {
+ this->nr_alloc = alloc_nr(this->nr_alloc);
+ this->head = xrealloc(this->head, this->nr_alloc * 20);
+ }
+ memcpy(this->head[this->nr_heads++], sha1, 20);
+ return 0;
+}
+
+/* Returns non-zero when we detect that the info in the
+ * old file is useless.
+ */
+static int parse_pack_def(const char *line, int old_cnt)
+{
+ struct pack_info *i = find_pack_by_name(line + 2);
+ if (i) {
+ i->old_num = old_cnt;
+ return 0;
+ }
+ else {
+ /* The file describes a pack that is no longer here;
+ * dependencies between packs needs to be recalculated.
+ */
+ return 1;
+ }
+}
+
+/* Returns non-zero when we detect that the info in the
+ * old file is useless.
+ */
+static int parse_depend_def(char *line)
+{
+ unsigned long num;
+ char *cp, *ep;
+ struct pack_info *this, *that;
+
+ cp = line + 2;
+ num = strtoul(cp, &ep, 10);
+ if (ep == cp)
+ return error("invalid input %s", line);
+ this = find_pack_by_old_num(num);
+ if (!this)
+ return 0;
+ while (ep && *(cp = ep)) {
+ num = strtoul(cp, &ep, 10);
+ if (ep == cp)
+ break;
+ that = find_pack_by_old_num(num);
+ if (!that)
+ /* The pack this one depends on does not
+ * exist; this should not happen because
+ * we write out the list of packs first and
+ * then dependency information, but it means
+ * the file is useless anyway.
+ */
+ return 1;
+ this->dep[that->new_num] = 1;
+ }
+ return 0;
+}
+
+/* Returns non-zero when we detect that the info in the
+ * old file is useless.
+ */
+static int parse_head_def(char *line)
+{
+ unsigned char sha1[20];
+ unsigned long num;
+ char *cp, *ep;
+ struct pack_info *this;
+ struct object *o;
+
+ cp = line + 2;
+ num = strtoul(cp, &ep, 10);
+ if (ep == cp || *ep++ != ' ')
+ return error("invalid input ix %s", line);
+ this = find_pack_by_old_num(num);
+ if (!this)
+ return 1; /* You know the drill. */
+ if (get_sha1_hex(ep, sha1) || ep[40] != ' ')
+ return error("invalid input sha1 %s (%s)", line, ep);
+ if ((o = parse_object_cheap(sha1)) == NULL)
+ return error("no such object: %s", line);
+ return add_head_def(this, sha1);
+}
+
+/* Returns non-zero when we detect that the info in the
+ * old file is useless.
+ */
+static int read_pack_info_file(const char *infofile)
+{
+ FILE *fp;
+ char line[1000];
+ int old_cnt = 0;
+
+ fp = fopen(infofile, "r");
+ if (!fp)
+ return 1; /* nonexisting is not an error. */
+
+ while (fgets(line, sizeof(line), fp)) {
+ int len = strlen(line);
+ if (line[len-1] == '\n')
+ line[len-1] = 0;
+
+ switch (line[0]) {
+ case 'P': /* P name */
+ if (parse_pack_def(line, old_cnt++))
+ goto out_stale;
+ break;
+ case 'D': /* D ix dep-ix1 dep-ix2... */
+ if (parse_depend_def(line))
+ goto out_stale;
+ break;
+ case 'T': /* T ix sha1 type */
+ if (parse_head_def(line))
+ goto out_stale;
+ break;
+ default:
+ error("unrecognized: %s", line);
+ break;
+ }
+ }
+ fclose(fp);
+ return 0;
+ out_stale:
+ fclose(fp);
+ return 1;
+}
+
+/* We sort the packs according to the date of the latest commit. That
+ * in turn indicates how young the pack is, and in general we would
+ * want to depend on younger packs.
+ */
+static unsigned long get_latest_commit_date(struct packed_git *p)
+{
+ unsigned char sha1[20];
+ struct object *o;
+ int num = num_packed_objects(p);
+ int i;
+ unsigned long latest = 0;
+
+ for (i = 0; i < num; i++) {
+ if (nth_packed_object_sha1(p, i, sha1))
+ die("corrupt pack file %s?", p->pack_name);
+ if ((o = parse_object_cheap(sha1)) == NULL)
+ die("cannot parse %s", sha1_to_hex(sha1));
+ if (o->type == commit_type) {
+ struct commit *commit = (struct commit *)o;
+ if (latest < commit->date)
+ latest = commit->date;
+ }
+ }
+ return latest;
+}
+
+static int compare_info(const void *a_, const void *b_)
+{
+ struct pack_info * const* a = a_;
+ struct pack_info * const* b = b_;
+
+ if (0 <= (*a)->old_num && 0 <= (*b)->old_num)
+ /* Keep the order in the original */
+ return (*a)->old_num - (*b)->old_num;
+ else if (0 <= (*a)->old_num)
+ /* Only A existed in the original so B is obviously newer */
+ return -1;
+ else if (0 <= (*b)->old_num)
+ /* The other way around. */
+ return 1;
+
+ if ((*a)->latest < (*b)->latest)
+ return -1;
+ else if ((*a)->latest == (*b)->latest)
+ return 0;
+ else
+ return 1;
+}
+
+static void init_pack_info(const char *infofile, int force)
+{
+ struct packed_git *p;
+ int stale;
+ int i = 0;
+ char *dep_temp;
+
+ objdir = get_object_directory();
+ objdirlen = strlen(objdir);
+
+ prepare_packed_git();
+ for (p = packed_git; p; p = p->next) {
+ /* we ignore things on alternate path since they are
+ * not available to the pullers in general.
+ */
+ if (strncmp(p->pack_name, objdir, objdirlen) ||
+ strncmp(p->pack_name + objdirlen, "/pack/", 6))
+ continue;
+ i++;
+ }
+ num_pack = i;
+ info = xcalloc(num_pack, sizeof(struct pack_info *));
+ for (i = 0, p = packed_git; p; p = p->next) {
+ if (strncmp(p->pack_name, objdir, objdirlen) ||
+ p->pack_name[objdirlen] != '/')
+ continue;
+ info[i] = xcalloc(1, sizeof(struct pack_info) + num_pack);
+ info[i]->p = p;
+ info[i]->old_num = -1;
+ i++;
+ }
+
+ if (infofile && !force)
+ stale = read_pack_info_file(infofile);
+ else
+ stale = 1;
+
+ for (i = 0; i < num_pack; i++) {
+ if (stale) {
+ info[i]->old_num = -1;
+ memset(info[i]->dep, 0, num_pack);
+ info[i]->nr_heads = 0;
+ }
+ if (info[i]->old_num < 0)
+ info[i]->latest = get_latest_commit_date(info[i]->p);
+ }
+
+ qsort(info, num_pack, sizeof(info[0]), compare_info);
+ for (i = 0; i < num_pack; i++)
+ info[i]->new_num = i;
+
+ /* we need to fix up the dependency information
+ * for the old ones.
+ */
+ dep_temp = NULL;
+ for (i = 0; i < num_pack; i++) {
+ int old;
+
+ if (info[i]->old_num < 0)
+ continue;
+ if (! dep_temp)
+ dep_temp = xmalloc(num_pack);
+ memset(dep_temp, 0, num_pack);
+ for (old = 0; old < num_pack; old++) {
+ struct pack_info *base;
+ if (!info[i]->dep[old])
+ continue;
+ base = find_pack_by_old_num(old);
+ if (!base)
+ die("internal error renumbering");
+ dep_temp[base->new_num] = 1;
+ }
+ memcpy(info[i]->dep, dep_temp, num_pack);
+ }
+ free(dep_temp);
+}
+
+static void write_pack_info_file(FILE *fp)
+{
+ int i, j;
+ for (i = 0; i < num_pack; i++)
+ fprintf(fp, "P %s\n", info[i]->p->pack_name + objdirlen + 6);
+
+ for (i = 0; i < num_pack; i++) {
+ fprintf(fp, "D %1d", i);
+ for (j = 0; j < num_pack; j++) {
+ if ((i == j) || !(info[i]->dep[j]))
+ continue;
+ fprintf(fp, " %1d", j);
+ }
+ fputc('\n', fp);
+ }
+
+ for (i = 0; i < num_pack; i++) {
+ struct pack_info *this = info[i];
+ for (j = 0; j < this->nr_heads; j++) {
+ struct object *o = lookup_object(this->head[j]);
+ fprintf(fp, "T %1d %s %s\n",
+ i, sha1_to_hex(this->head[j]), o->type);
+ }
+ }
+
+}
+
+#define REFERENCED 01
+#define INTERNAL 02
+#define EMITTED 04
+
+static void show(struct object *o, int pack_ix)
+{
+ /*
+ * We are interested in objects that are not referenced,
+ * and objects that are referenced but not internal.
+ */
+ if (o->flags & EMITTED)
+ return;
+
+ if (!(o->flags & REFERENCED))
+ add_head_def(info[pack_ix], o->sha1);
+ else if ((o->flags & REFERENCED) && !(o->flags & INTERNAL)) {
+ int i;
+
+ /* Which pack contains this object? That is what
+ * pack_ix can depend on. We earlier sorted info
+ * array from youngest to oldest, so try newer packs
+ * first to favor them here.
+ */
+ for (i = num_pack - 1; 0 <= i; i--) {
+ struct packed_git *p = info[i]->p;
+ struct pack_entry ent;
+ if (find_pack_entry_one(o->sha1, &ent, p)) {
+ info[pack_ix]->dep[i] = 1;
+ break;
+ }
+ }
+ }
+ o->flags |= EMITTED;
+}
+
+static void find_pack_info_one(int pack_ix)
+{
+ unsigned char sha1[20];
+ struct object *o;
+ struct object_list *ref;
+ int i;
+ struct packed_git *p = info[pack_ix]->p;
+ int num = num_packed_objects(p);
+
+ /* Scan objects, clear flags from all the edge ones and
+ * internal ones, possibly marked in the previous round.
+ */
+ for (i = 0; i < num; i++) {
+ if (nth_packed_object_sha1(p, i, sha1))
+ die("corrupt pack file %s?", p->pack_name);
+ if ((o = lookup_object(sha1)) == NULL)
+ die("cannot parse %s", sha1_to_hex(sha1));
+ for (ref = o->refs; ref; ref = ref->next)
+ ref->item->flags = 0;
+ o->flags = 0;
+ }
+
+ /* Mark all the internal ones */
+ for (i = 0; i < num; i++) {
+ if (nth_packed_object_sha1(p, i, sha1))
+ die("corrupt pack file %s?", p->pack_name);
+ if ((o = lookup_object(sha1)) == NULL)
+ die("cannot find %s", sha1_to_hex(sha1));
+ for (ref = o->refs; ref; ref = ref->next)
+ ref->item->flags |= REFERENCED;
+ o->flags |= INTERNAL;
+ }
+
+ for (i = 0; i < num; i++) {
+ if (nth_packed_object_sha1(p, i, sha1))
+ die("corrupt pack file %s?", p->pack_name);
+ if ((o = lookup_object(sha1)) == NULL)
+ die("cannot find %s", sha1_to_hex(sha1));
+
+ show(o, pack_ix);
+ for (ref = o->refs; ref; ref = ref->next)
+ show(ref->item, pack_ix);
+ }
+
+}
+
+static void find_pack_info(void)
+{
+ int i;
+ for (i = 0; i < num_pack; i++) {
+ /* The packed objects are cast in stone, and a head
+ * in a pack will stay as head, so is the set of missing
+ * objects. If the repo has been reorganized and we
+ * are missing some packs available back then, we have
+ * already discarded the info read from the file, so
+ * we will find (old_num < 0) in that case.
+ */
+ if (0 <= info[i]->old_num)
+ continue;
+ find_pack_info_one(i);
+ }
+}
+
+static int update_info_packs(int force)
+{
+ char infofile[PATH_MAX];
+ char name[PATH_MAX];
+ int namelen;
+ FILE *fp;
+
+ namelen = sprintf(infofile, "%s/info/packs", get_object_directory());
+ strcpy(name, infofile);
+ strcpy(name + namelen, "+");
+
+ init_pack_info(infofile, force);
+ find_pack_info();
+
+ safe_create_leading_directories(name);
+ fp = fopen(name, "w");
+ if (!fp)
+ return error("cannot open %s", name);
+ write_pack_info_file(fp);
+ fclose(fp);
+ rename(name, infofile);
+ return 0;
+}
+
+/* rev-cache */
+static int record_rev_cache_ref(const char *path, const unsigned char *sha1)
+{
+ struct commit *commit;
+ if (!(commit = lookup_commit_reference(sha1)))
+ return error("not a commit: %s", sha1_to_hex(sha1));
+ return record_rev_cache(commit->object.sha1, NULL);
+}
+
+static int update_info_revs(int force)
+{
+ char *path0 = strdup(git_path("info/rev-cache"));
+ int len = strlen(path0);
+ char *path1 = xmalloc(len + 2);
+
+ strcpy(path1, path0);
+ strcpy(path1 + len, "+");
+
+ /* read existing rev-cache */
+ if (!force)
+ read_rev_cache(path0, NULL, 0);
+ safe_create_leading_directories(path0);
+
+ for_each_ref(record_rev_cache_ref);
+
+ /* update the rev-cache database */
+ write_rev_cache(path1, force ? "/dev/null" : path0);
+ rename(path1, path0);
+ free(path1);
+ free(path0);
+ return 0;
+}
+
+/* public */
+int update_server_info(int force)
+{
+ /* We would add more dumb-server support files later,
+ * including index of available pack files and their
+ * intended audiences.
+ */
+ int errs = 0;
+
+ errs = errs | update_info_refs(force);
+ errs = errs | update_info_packs(force);
+ errs = errs | update_info_revs(force);
+
+ return errs;
+}
diff --git a/show-rev-cache.c b/show-rev-cache.c
new file mode 100644
index 0000000..fa92b87
--- /dev/null
+++ b/show-rev-cache.c
@@ -0,0 +1,18 @@
+#include "cache.h"
+#include "rev-cache.h"
+
+static char *show_rev_cache_usage =
+"git-show-rev-cache <rev-cache-file>";
+
+int main(int ac, char **av)
+{
+ while (1 < ac && av[0][1] == '-') {
+ /* do flags here */
+ break;
+ ac--; av++;
+ }
+ if (ac != 2)
+ usage(show_rev_cache_usage);
+
+ return read_rev_cache(av[1], stdout, 1);
+}
diff --git a/update-server-info.c b/update-server-info.c
new file mode 100644
index 0000000..e824f62
--- /dev/null
+++ b/update-server-info.c
@@ -0,0 +1,23 @@
+#include "cache.h"
+
+static const char update_server_info_usage[] =
+"git-update-server-info [--force]";
+
+int main(int ac, char **av)
+{
+ int i;
+ int force = 0;
+ for (i = 1; i < ac; i++) {
+ if (av[i][0] == '-') {
+ if (!strcmp("--force", av[i]) ||
+ !strcmp("-f", av[i]))
+ force = 1;
+ else
+ usage(update_server_info_usage);
+ }
+ }
+ if (i != ac)
+ usage(update_server_info_usage);
+
+ return !!update_server_info(force);
+}