git/builtin-pack-refs.c
Junio C Hamano f4204ab9f6 Store peeled refs in packed-refs (take 2).
This fixes the previous implementation which failed to optimize
repositories with tons of lightweight tags.  The updated
packed-refs format begins with "# packed-refs with:" line that
lists the kind of extended data the file records.  Currently,
there is only one such extension defined, "peeled".  This stores
the "peeled tag" on a line that immediately follows a line for a
tag object itself in the format "^<sha-1>".

The header line itself and any extended data are ignored by
older implementation, so packed-refs file generated with this
version can still be used by older git.  packed-refs made by
older git can of course be used with this version.

Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-11-21 23:37:35 -08:00

128 lines
2.7 KiB
C

#include "cache.h"
#include "refs.h"
#include "object.h"
#include "tag.h"
static const char builtin_pack_refs_usage[] =
"git-pack-refs [--all] [--prune]";
struct ref_to_prune {
struct ref_to_prune *next;
unsigned char sha1[20];
char name[FLEX_ARRAY];
};
struct pack_refs_cb_data {
int prune;
int all;
struct ref_to_prune *ref_to_prune;
FILE *refs_file;
};
static int do_not_prune(int flags)
{
/* If it is already packed or if it is a symref,
* do not prune it.
*/
return (flags & (REF_ISSYMREF|REF_ISPACKED));
}
static int handle_one_ref(const char *path, const unsigned char *sha1,
int flags, void *cb_data)
{
struct pack_refs_cb_data *cb = cb_data;
int is_tag_ref;
/* Do not pack the symbolic refs */
if ((flags & REF_ISSYMREF))
return 0;
is_tag_ref = !strncmp(path, "refs/tags/", 10);
if (!cb->all && !is_tag_ref)
return 0;
fprintf(cb->refs_file, "%s %s\n", sha1_to_hex(sha1), path);
if (is_tag_ref) {
struct object *o = parse_object(sha1);
if (o->type == OBJ_TAG) {
o = deref_tag(o, path, 0);
if (o)
fprintf(cb->refs_file, "^%s\n",
sha1_to_hex(o->sha1));
}
}
if (cb->prune && !do_not_prune(flags)) {
int namelen = strlen(path) + 1;
struct ref_to_prune *n = xcalloc(1, sizeof(*n) + namelen);
hashcpy(n->sha1, sha1);
strcpy(n->name, path);
n->next = cb->ref_to_prune;
cb->ref_to_prune = n;
}
return 0;
}
/* make sure nobody touched the ref, and unlink */
static void prune_ref(struct ref_to_prune *r)
{
struct ref_lock *lock = lock_ref_sha1(r->name + 5, r->sha1);
if (lock) {
unlink(git_path("%s", r->name));
unlock_ref(lock);
}
}
static void prune_refs(struct ref_to_prune *r)
{
while (r) {
prune_ref(r);
r = r->next;
}
}
static struct lock_file packed;
int cmd_pack_refs(int argc, const char **argv, const char *prefix)
{
int fd, i;
struct pack_refs_cb_data cbdata;
memset(&cbdata, 0, sizeof(cbdata));
for (i = 1; i < argc; i++) {
const char *arg = argv[i];
if (!strcmp(arg, "--prune")) {
cbdata.prune = 1;
continue;
}
if (!strcmp(arg, "--all")) {
cbdata.all = 1;
continue;
}
/* perhaps other parameters later... */
break;
}
if (i != argc)
usage(builtin_pack_refs_usage);
fd = hold_lock_file_for_update(&packed, git_path("packed-refs"), 1);
cbdata.refs_file = fdopen(fd, "w");
if (!cbdata.refs_file)
die("unable to create ref-pack file structure (%s)",
strerror(errno));
/* perhaps other traits later as well */
fprintf(cbdata.refs_file, "# pack-refs with: peeled \n");
for_each_ref(handle_one_ref, &cbdata);
fflush(cbdata.refs_file);
fsync(fd);
fclose(cbdata.refs_file);
if (commit_lock_file(&packed) < 0)
die("unable to overwrite old ref-pack file (%s)", strerror(errno));
if (cbdata.prune)
prune_refs(cbdata.ref_to_prune);
return 0;
}