4 #include "refs-internal.h"
6 #include "packed-backend.h"
7 #include "../iterator.h"
8 #include "../dir-iterator.h"
9 #include "../lockfile.h"
10 #include "../object.h"
12 #include "../chdir-notify.h"
16 * This backend uses the following flags in `ref_update::flags` for
17 * internal bookkeeping purposes. Their numerical values must not
18 * conflict with REF_NO_DEREF, REF_FORCE_CREATE_REFLOG, REF_HAVE_NEW,
19 * REF_HAVE_OLD, or REF_IS_PRUNING, which are also stored in
20 * `ref_update::flags`.
24 * Used as a flag in ref_update::flags when a loose ref is being
25 * pruned. This flag must only be used when REF_NO_DEREF is set.
27 #define REF_IS_PRUNING (1 << 4)
30 * Flag passed to lock_ref_sha1_basic() telling it to tolerate broken
31 * refs (i.e., because the reference is about to be deleted anyway).
33 #define REF_DELETING (1 << 5)
36 * Used as a flag in ref_update::flags when the lockfile needs to be
39 #define REF_NEEDS_COMMIT (1 << 6)
42 * Used as a flag in ref_update::flags when we want to log a ref
43 * update but not actually perform it. This is used when a symbolic
44 * ref update is split up.
46 #define REF_LOG_ONLY (1 << 7)
49 * Used as a flag in ref_update::flags when the ref_update was via an
52 #define REF_UPDATE_VIA_HEAD (1 << 8)
55 * Used as a flag in ref_update::flags when the loose reference has
58 #define REF_DELETED_LOOSE (1 << 9)
63 struct object_id old_oid
;
66 struct files_ref_store
{
67 struct ref_store base
;
68 unsigned int store_flags
;
73 struct ref_cache
*loose
;
75 struct ref_store
*packed_ref_store
;
78 static void clear_loose_ref_cache(struct files_ref_store
*refs
)
81 free_ref_cache(refs
->loose
);
87 * Create a new submodule ref cache and add it to the internal
90 static struct ref_store
*files_ref_store_create(const char *gitdir
,
93 struct files_ref_store
*refs
= xcalloc(1, sizeof(*refs
));
94 struct ref_store
*ref_store
= (struct ref_store
*)refs
;
95 struct strbuf sb
= STRBUF_INIT
;
97 base_ref_store_init(ref_store
, &refs_be_files
);
98 refs
->store_flags
= flags
;
100 refs
->gitdir
= xstrdup(gitdir
);
101 get_common_dir_noenv(&sb
, gitdir
);
102 refs
->gitcommondir
= strbuf_detach(&sb
, NULL
);
103 strbuf_addf(&sb
, "%s/packed-refs", refs
->gitcommondir
);
104 refs
->packed_ref_store
= packed_ref_store_create(sb
.buf
, flags
);
107 chdir_notify_reparent("files-backend $GIT_DIR",
109 chdir_notify_reparent("files-backend $GIT_COMMONDIR",
110 &refs
->gitcommondir
);
116 * Die if refs is not the main ref store. caller is used in any
117 * necessary error messages.
119 static void files_assert_main_repository(struct files_ref_store
*refs
,
122 if (refs
->store_flags
& REF_STORE_MAIN
)
125 BUG("operation %s only allowed for main ref store", caller
);
129 * Downcast ref_store to files_ref_store. Die if ref_store is not a
130 * files_ref_store. required_flags is compared with ref_store's
131 * store_flags to ensure the ref_store has all required capabilities.
132 * "caller" is used in any necessary error messages.
134 static struct files_ref_store
*files_downcast(struct ref_store
*ref_store
,
135 unsigned int required_flags
,
138 struct files_ref_store
*refs
;
140 if (ref_store
->be
!= &refs_be_files
)
141 BUG("ref_store is type \"%s\" not \"files\" in %s",
142 ref_store
->be
->name
, caller
);
144 refs
= (struct files_ref_store
*)ref_store
;
146 if ((refs
->store_flags
& required_flags
) != required_flags
)
147 BUG("operation %s requires abilities 0x%x, but only have 0x%x",
148 caller
, required_flags
, refs
->store_flags
);
153 static void files_reflog_path_other_worktrees(struct files_ref_store
*refs
,
157 const char *real_ref
;
158 const char *worktree_name
;
161 if (parse_worktree_ref(refname
, &worktree_name
, &length
, &real_ref
))
162 BUG("refname %s is not a other-worktree ref", refname
);
165 strbuf_addf(sb
, "%s/worktrees/%.*s/logs/%s", refs
->gitcommondir
,
166 length
, worktree_name
, real_ref
);
168 strbuf_addf(sb
, "%s/logs/%s", refs
->gitcommondir
,
172 static void files_reflog_path(struct files_ref_store
*refs
,
176 switch (ref_type(refname
)) {
177 case REF_TYPE_PER_WORKTREE
:
178 case REF_TYPE_PSEUDOREF
:
179 strbuf_addf(sb
, "%s/logs/%s", refs
->gitdir
, refname
);
181 case REF_TYPE_OTHER_PSEUDOREF
:
182 case REF_TYPE_MAIN_PSEUDOREF
:
183 return files_reflog_path_other_worktrees(refs
, sb
, refname
);
184 case REF_TYPE_NORMAL
:
185 strbuf_addf(sb
, "%s/logs/%s", refs
->gitcommondir
, refname
);
188 BUG("unknown ref type %d of ref %s",
189 ref_type(refname
), refname
);
193 static void files_ref_path(struct files_ref_store
*refs
,
197 switch (ref_type(refname
)) {
198 case REF_TYPE_PER_WORKTREE
:
199 case REF_TYPE_PSEUDOREF
:
200 strbuf_addf(sb
, "%s/%s", refs
->gitdir
, refname
);
202 case REF_TYPE_MAIN_PSEUDOREF
:
203 if (!skip_prefix(refname
, "main-worktree/", &refname
))
204 BUG("ref %s is not a main pseudoref", refname
);
206 case REF_TYPE_OTHER_PSEUDOREF
:
207 case REF_TYPE_NORMAL
:
208 strbuf_addf(sb
, "%s/%s", refs
->gitcommondir
, refname
);
211 BUG("unknown ref type %d of ref %s",
212 ref_type(refname
), refname
);
217 * Manually add refs/bisect, refs/rewritten and refs/worktree, which, being
218 * per-worktree, might not appear in the directory listing for
219 * refs/ in the main repo.
221 static void add_per_worktree_entries_to_dir(struct ref_dir
*dir
, const char *dirname
)
223 const char *prefixes
[] = { "refs/bisect/", "refs/worktree/", "refs/rewritten/" };
226 if (strcmp(dirname
, "refs/"))
229 for (ip
= 0; ip
< ARRAY_SIZE(prefixes
); ip
++) {
230 const char *prefix
= prefixes
[ip
];
231 int prefix_len
= strlen(prefix
);
232 struct ref_entry
*child_entry
;
235 pos
= search_ref_dir(dir
, prefix
, prefix_len
);
238 child_entry
= create_dir_entry(dir
->cache
, prefix
, prefix_len
, 1);
239 add_entry_to_dir(dir
, child_entry
);
244 * Read the loose references from the namespace dirname into dir
245 * (without recursing). dirname must end with '/'. dir must be the
246 * directory entry corresponding to dirname.
248 static void loose_fill_ref_dir(struct ref_store
*ref_store
,
249 struct ref_dir
*dir
, const char *dirname
)
251 struct files_ref_store
*refs
=
252 files_downcast(ref_store
, REF_STORE_READ
, "fill_ref_dir");
255 int dirnamelen
= strlen(dirname
);
256 struct strbuf refname
;
257 struct strbuf path
= STRBUF_INIT
;
260 files_ref_path(refs
, &path
, dirname
);
261 path_baselen
= path
.len
;
263 d
= opendir(path
.buf
);
265 strbuf_release(&path
);
269 strbuf_init(&refname
, dirnamelen
+ 257);
270 strbuf_add(&refname
, dirname
, dirnamelen
);
272 while ((de
= readdir(d
)) != NULL
) {
273 struct object_id oid
;
277 if (de
->d_name
[0] == '.')
279 if (ends_with(de
->d_name
, ".lock"))
281 strbuf_addstr(&refname
, de
->d_name
);
282 strbuf_addstr(&path
, de
->d_name
);
283 if (stat(path
.buf
, &st
) < 0) {
284 ; /* silently ignore */
285 } else if (S_ISDIR(st
.st_mode
)) {
286 strbuf_addch(&refname
, '/');
287 add_entry_to_dir(dir
,
288 create_dir_entry(dir
->cache
, refname
.buf
,
291 if (!refs_resolve_ref_unsafe(&refs
->base
,
296 flag
|= REF_ISBROKEN
;
297 } else if (is_null_oid(&oid
)) {
299 * It is so astronomically unlikely
300 * that null_oid is the OID of an
301 * actual object that we consider its
302 * appearance in a loose reference
303 * file to be repo corruption
304 * (probably due to a software bug).
306 flag
|= REF_ISBROKEN
;
309 if (check_refname_format(refname
.buf
,
310 REFNAME_ALLOW_ONELEVEL
)) {
311 if (!refname_is_safe(refname
.buf
))
312 die("loose refname is dangerous: %s", refname
.buf
);
314 flag
|= REF_BAD_NAME
| REF_ISBROKEN
;
316 add_entry_to_dir(dir
,
317 create_ref_entry(refname
.buf
, &oid
, flag
));
319 strbuf_setlen(&refname
, dirnamelen
);
320 strbuf_setlen(&path
, path_baselen
);
322 strbuf_release(&refname
);
323 strbuf_release(&path
);
326 add_per_worktree_entries_to_dir(dir
, dirname
);
329 static struct ref_cache
*get_loose_ref_cache(struct files_ref_store
*refs
)
333 * Mark the top-level directory complete because we
334 * are about to read the only subdirectory that can
337 refs
->loose
= create_ref_cache(&refs
->base
, loose_fill_ref_dir
);
339 /* We're going to fill the top level ourselves: */
340 refs
->loose
->root
->flag
&= ~REF_INCOMPLETE
;
343 * Add an incomplete entry for "refs/" (to be filled
346 add_entry_to_dir(get_ref_dir(refs
->loose
->root
),
347 create_dir_entry(refs
->loose
, "refs/", 5, 1));
352 static int files_read_raw_ref(struct ref_store
*ref_store
,
353 const char *refname
, struct object_id
*oid
,
354 struct strbuf
*referent
, unsigned int *type
)
356 struct files_ref_store
*refs
=
357 files_downcast(ref_store
, REF_STORE_READ
, "read_raw_ref");
358 struct strbuf sb_contents
= STRBUF_INIT
;
359 struct strbuf sb_path
= STRBUF_INIT
;
367 int remaining_retries
= 3;
370 strbuf_reset(&sb_path
);
372 files_ref_path(refs
, &sb_path
, refname
);
378 * We might have to loop back here to avoid a race
379 * condition: first we lstat() the file, then we try
380 * to read it as a link or as a file. But if somebody
381 * changes the type of the file (file <-> directory
382 * <-> symlink) between the lstat() and reading, then
383 * we don't want to report that as an error but rather
384 * try again starting with the lstat().
386 * We'll keep a count of the retries, though, just to avoid
387 * any confusing situation sending us into an infinite loop.
390 if (remaining_retries
-- <= 0)
393 if (lstat(path
, &st
) < 0) {
396 if (refs_read_raw_ref(refs
->packed_ref_store
, refname
,
397 oid
, referent
, type
)) {
405 /* Follow "normalized" - ie "refs/.." symlinks by hand */
406 if (S_ISLNK(st
.st_mode
)) {
407 strbuf_reset(&sb_contents
);
408 if (strbuf_readlink(&sb_contents
, path
, st
.st_size
) < 0) {
409 if (errno
== ENOENT
|| errno
== EINVAL
)
410 /* inconsistent with lstat; retry */
415 if (starts_with(sb_contents
.buf
, "refs/") &&
416 !check_refname_format(sb_contents
.buf
, 0)) {
417 strbuf_swap(&sb_contents
, referent
);
418 *type
|= REF_ISSYMREF
;
423 * It doesn't look like a refname; fall through to just
424 * treating it like a non-symlink, and reading whatever it
429 /* Is it a directory? */
430 if (S_ISDIR(st
.st_mode
)) {
432 * Even though there is a directory where the loose
433 * ref is supposed to be, there could still be a
436 if (refs_read_raw_ref(refs
->packed_ref_store
, refname
,
437 oid
, referent
, type
)) {
446 * Anything else, just open it and try to use it as
449 fd
= open(path
, O_RDONLY
);
451 if (errno
== ENOENT
&& !S_ISLNK(st
.st_mode
))
452 /* inconsistent with lstat; retry */
457 strbuf_reset(&sb_contents
);
458 if (strbuf_read(&sb_contents
, fd
, 256) < 0) {
459 int save_errno
= errno
;
465 strbuf_rtrim(&sb_contents
);
466 buf
= sb_contents
.buf
;
467 if (starts_with(buf
, "ref:")) {
469 while (isspace(*buf
))
472 strbuf_reset(referent
);
473 strbuf_addstr(referent
, buf
);
474 *type
|= REF_ISSYMREF
;
480 * Please note that FETCH_HEAD has additional
481 * data after the sha.
483 if (parse_oid_hex(buf
, oid
, &p
) ||
484 (*p
!= '\0' && !isspace(*p
))) {
485 *type
|= REF_ISBROKEN
;
494 strbuf_release(&sb_path
);
495 strbuf_release(&sb_contents
);
500 static void unlock_ref(struct ref_lock
*lock
)
502 rollback_lock_file(&lock
->lk
);
503 free(lock
->ref_name
);
508 * Lock refname, without following symrefs, and set *lock_p to point
509 * at a newly-allocated lock object. Fill in lock->old_oid, referent,
510 * and type similarly to read_raw_ref().
512 * The caller must verify that refname is a "safe" reference name (in
513 * the sense of refname_is_safe()) before calling this function.
515 * If the reference doesn't already exist, verify that refname doesn't
516 * have a D/F conflict with any existing references. extras and skip
517 * are passed to refs_verify_refname_available() for this check.
519 * If mustexist is not set and the reference is not found or is
520 * broken, lock the reference anyway but clear old_oid.
522 * Return 0 on success. On failure, write an error message to err and
523 * return TRANSACTION_NAME_CONFLICT or TRANSACTION_GENERIC_ERROR.
525 * Implementation note: This function is basically
530 * but it includes a lot more code to
531 * - Deal with possible races with other processes
532 * - Avoid calling refs_verify_refname_available() when it can be
533 * avoided, namely if we were successfully able to read the ref
534 * - Generate informative error messages in the case of failure
536 static int lock_raw_ref(struct files_ref_store
*refs
,
537 const char *refname
, int mustexist
,
538 const struct string_list
*extras
,
539 const struct string_list
*skip
,
540 struct ref_lock
**lock_p
,
541 struct strbuf
*referent
,
545 struct ref_lock
*lock
;
546 struct strbuf ref_file
= STRBUF_INIT
;
547 int attempts_remaining
= 3;
548 int ret
= TRANSACTION_GENERIC_ERROR
;
551 files_assert_main_repository(refs
, "lock_raw_ref");
555 /* First lock the file so it can't change out from under us. */
557 *lock_p
= lock
= xcalloc(1, sizeof(*lock
));
559 lock
->ref_name
= xstrdup(refname
);
560 files_ref_path(refs
, &ref_file
, refname
);
563 switch (safe_create_leading_directories(ref_file
.buf
)) {
568 * Suppose refname is "refs/foo/bar". We just failed
569 * to create the containing directory, "refs/foo",
570 * because there was a non-directory in the way. This
571 * indicates a D/F conflict, probably because of
572 * another reference such as "refs/foo". There is no
573 * reason to expect this error to be transitory.
575 if (refs_verify_refname_available(&refs
->base
, refname
,
576 extras
, skip
, err
)) {
579 * To the user the relevant error is
580 * that the "mustexist" reference is
584 strbuf_addf(err
, "unable to resolve reference '%s'",
588 * The error message set by
589 * refs_verify_refname_available() is
592 ret
= TRANSACTION_NAME_CONFLICT
;
596 * The file that is in the way isn't a loose
597 * reference. Report it as a low-level
600 strbuf_addf(err
, "unable to create lock file %s.lock; "
601 "non-directory in the way",
606 /* Maybe another process was tidying up. Try again. */
607 if (--attempts_remaining
> 0)
611 strbuf_addf(err
, "unable to create directory for %s",
616 if (hold_lock_file_for_update_timeout(
617 &lock
->lk
, ref_file
.buf
, LOCK_NO_DEREF
,
618 get_files_ref_lock_timeout_ms()) < 0) {
619 if (errno
== ENOENT
&& --attempts_remaining
> 0) {
621 * Maybe somebody just deleted one of the
622 * directories leading to ref_file. Try
627 unable_to_lock_message(ref_file
.buf
, errno
, err
);
633 * Now we hold the lock and can read the reference without
634 * fear that its value will change.
637 if (files_read_raw_ref(&refs
->base
, refname
,
638 &lock
->old_oid
, referent
, type
)) {
639 if (errno
== ENOENT
) {
641 /* Garden variety missing reference. */
642 strbuf_addf(err
, "unable to resolve reference '%s'",
647 * Reference is missing, but that's OK. We
648 * know that there is not a conflict with
649 * another loose reference because
650 * (supposing that we are trying to lock
651 * reference "refs/foo/bar"):
653 * - We were successfully able to create
654 * the lockfile refs/foo/bar.lock, so we
655 * know there cannot be a loose reference
658 * - We got ENOENT and not EISDIR, so we
659 * know that there cannot be a loose
660 * reference named "refs/foo/bar/baz".
663 } else if (errno
== EISDIR
) {
665 * There is a directory in the way. It might have
666 * contained references that have been deleted. If
667 * we don't require that the reference already
668 * exists, try to remove the directory so that it
669 * doesn't cause trouble when we want to rename the
670 * lockfile into place later.
673 /* Garden variety missing reference. */
674 strbuf_addf(err
, "unable to resolve reference '%s'",
677 } else if (remove_dir_recursively(&ref_file
,
678 REMOVE_DIR_EMPTY_ONLY
)) {
679 if (refs_verify_refname_available(
680 &refs
->base
, refname
,
681 extras
, skip
, err
)) {
683 * The error message set by
684 * verify_refname_available() is OK.
686 ret
= TRANSACTION_NAME_CONFLICT
;
690 * We can't delete the directory,
691 * but we also don't know of any
692 * references that it should
695 strbuf_addf(err
, "there is a non-empty directory '%s' "
696 "blocking reference '%s'",
697 ref_file
.buf
, refname
);
701 } else if (errno
== EINVAL
&& (*type
& REF_ISBROKEN
)) {
702 strbuf_addf(err
, "unable to resolve reference '%s': "
703 "reference broken", refname
);
706 strbuf_addf(err
, "unable to resolve reference '%s': %s",
707 refname
, strerror(errno
));
712 * If the ref did not exist and we are creating it,
713 * make sure there is no existing packed ref that
714 * conflicts with refname:
716 if (refs_verify_refname_available(
717 refs
->packed_ref_store
, refname
,
730 strbuf_release(&ref_file
);
734 struct files_ref_iterator
{
735 struct ref_iterator base
;
737 struct ref_iterator
*iter0
;
741 static int files_ref_iterator_advance(struct ref_iterator
*ref_iterator
)
743 struct files_ref_iterator
*iter
=
744 (struct files_ref_iterator
*)ref_iterator
;
747 while ((ok
= ref_iterator_advance(iter
->iter0
)) == ITER_OK
) {
748 if (iter
->flags
& DO_FOR_EACH_PER_WORKTREE_ONLY
&&
749 ref_type(iter
->iter0
->refname
) != REF_TYPE_PER_WORKTREE
)
752 if (!(iter
->flags
& DO_FOR_EACH_INCLUDE_BROKEN
) &&
753 !ref_resolves_to_object(iter
->iter0
->refname
,
758 iter
->base
.refname
= iter
->iter0
->refname
;
759 iter
->base
.oid
= iter
->iter0
->oid
;
760 iter
->base
.flags
= iter
->iter0
->flags
;
765 if (ref_iterator_abort(ref_iterator
) != ITER_DONE
)
771 static int files_ref_iterator_peel(struct ref_iterator
*ref_iterator
,
772 struct object_id
*peeled
)
774 struct files_ref_iterator
*iter
=
775 (struct files_ref_iterator
*)ref_iterator
;
777 return ref_iterator_peel(iter
->iter0
, peeled
);
780 static int files_ref_iterator_abort(struct ref_iterator
*ref_iterator
)
782 struct files_ref_iterator
*iter
=
783 (struct files_ref_iterator
*)ref_iterator
;
787 ok
= ref_iterator_abort(iter
->iter0
);
789 base_ref_iterator_free(ref_iterator
);
793 static struct ref_iterator_vtable files_ref_iterator_vtable
= {
794 files_ref_iterator_advance
,
795 files_ref_iterator_peel
,
796 files_ref_iterator_abort
799 static struct ref_iterator
*files_ref_iterator_begin(
800 struct ref_store
*ref_store
,
801 const char *prefix
, unsigned int flags
)
803 struct files_ref_store
*refs
;
804 struct ref_iterator
*loose_iter
, *packed_iter
, *overlay_iter
;
805 struct files_ref_iterator
*iter
;
806 struct ref_iterator
*ref_iterator
;
807 unsigned int required_flags
= REF_STORE_READ
;
809 if (!(flags
& DO_FOR_EACH_INCLUDE_BROKEN
))
810 required_flags
|= REF_STORE_ODB
;
812 refs
= files_downcast(ref_store
, required_flags
, "ref_iterator_begin");
815 * We must make sure that all loose refs are read before
816 * accessing the packed-refs file; this avoids a race
817 * condition if loose refs are migrated to the packed-refs
818 * file by a simultaneous process, but our in-memory view is
819 * from before the migration. We ensure this as follows:
820 * First, we call start the loose refs iteration with its
821 * `prime_ref` argument set to true. This causes the loose
822 * references in the subtree to be pre-read into the cache.
823 * (If they've already been read, that's OK; we only need to
824 * guarantee that they're read before the packed refs, not
825 * *how much* before.) After that, we call
826 * packed_ref_iterator_begin(), which internally checks
827 * whether the packed-ref cache is up to date with what is on
828 * disk, and re-reads it if not.
831 loose_iter
= cache_ref_iterator_begin(get_loose_ref_cache(refs
),
835 * The packed-refs file might contain broken references, for
836 * example an old version of a reference that points at an
837 * object that has since been garbage-collected. This is OK as
838 * long as there is a corresponding loose reference that
839 * overrides it, and we don't want to emit an error message in
840 * this case. So ask the packed_ref_store for all of its
841 * references, and (if needed) do our own check for broken
842 * ones in files_ref_iterator_advance(), after we have merged
843 * the packed and loose references.
845 packed_iter
= refs_ref_iterator_begin(
846 refs
->packed_ref_store
, prefix
, 0,
847 DO_FOR_EACH_INCLUDE_BROKEN
);
849 overlay_iter
= overlay_ref_iterator_begin(loose_iter
, packed_iter
);
851 iter
= xcalloc(1, sizeof(*iter
));
852 ref_iterator
= &iter
->base
;
853 base_ref_iterator_init(ref_iterator
, &files_ref_iterator_vtable
,
854 overlay_iter
->ordered
);
855 iter
->iter0
= overlay_iter
;
862 * Verify that the reference locked by lock has the value old_oid
863 * (unless it is NULL). Fail if the reference doesn't exist and
864 * mustexist is set. Return 0 on success. On error, write an error
865 * message to err, set errno, and return a negative value.
867 static int verify_lock(struct ref_store
*ref_store
, struct ref_lock
*lock
,
868 const struct object_id
*old_oid
, int mustexist
,
873 if (refs_read_ref_full(ref_store
, lock
->ref_name
,
874 mustexist
? RESOLVE_REF_READING
: 0,
875 &lock
->old_oid
, NULL
)) {
877 int save_errno
= errno
;
878 strbuf_addf(err
, "can't verify ref '%s'", lock
->ref_name
);
882 oidclr(&lock
->old_oid
);
886 if (old_oid
&& !oideq(&lock
->old_oid
, old_oid
)) {
887 strbuf_addf(err
, "ref '%s' is at %s but expected %s",
889 oid_to_hex(&lock
->old_oid
),
890 oid_to_hex(old_oid
));
897 static int remove_empty_directories(struct strbuf
*path
)
900 * we want to create a file but there is a directory there;
901 * if that is an empty directory (or a directory that contains
902 * only empty directories), remove them.
904 return remove_dir_recursively(path
, REMOVE_DIR_EMPTY_ONLY
);
907 static int create_reflock(const char *path
, void *cb
)
909 struct lock_file
*lk
= cb
;
911 return hold_lock_file_for_update_timeout(
912 lk
, path
, LOCK_NO_DEREF
,
913 get_files_ref_lock_timeout_ms()) < 0 ? -1 : 0;
917 * Locks a ref returning the lock on success and NULL on failure.
918 * On failure errno is set to something meaningful.
920 static struct ref_lock
*lock_ref_oid_basic(struct files_ref_store
*refs
,
922 const struct object_id
*old_oid
,
923 const struct string_list
*extras
,
924 const struct string_list
*skip
,
925 unsigned int flags
, int *type
,
928 struct strbuf ref_file
= STRBUF_INIT
;
929 struct ref_lock
*lock
;
931 int mustexist
= (old_oid
&& !is_null_oid(old_oid
));
932 int resolve_flags
= RESOLVE_REF_NO_RECURSE
;
935 files_assert_main_repository(refs
, "lock_ref_oid_basic");
938 lock
= xcalloc(1, sizeof(struct ref_lock
));
941 resolve_flags
|= RESOLVE_REF_READING
;
942 if (flags
& REF_DELETING
)
943 resolve_flags
|= RESOLVE_REF_ALLOW_BAD_NAME
;
945 files_ref_path(refs
, &ref_file
, refname
);
946 resolved
= !!refs_resolve_ref_unsafe(&refs
->base
,
947 refname
, resolve_flags
,
948 &lock
->old_oid
, type
);
949 if (!resolved
&& errno
== EISDIR
) {
951 * we are trying to lock foo but we used to
952 * have foo/bar which now does not exist;
953 * it is normal for the empty directory 'foo'
956 if (remove_empty_directories(&ref_file
)) {
958 if (!refs_verify_refname_available(
960 refname
, extras
, skip
, err
))
961 strbuf_addf(err
, "there are still refs under '%s'",
965 resolved
= !!refs_resolve_ref_unsafe(&refs
->base
,
966 refname
, resolve_flags
,
967 &lock
->old_oid
, type
);
971 if (last_errno
!= ENOTDIR
||
972 !refs_verify_refname_available(&refs
->base
, refname
,
974 strbuf_addf(err
, "unable to resolve reference '%s': %s",
975 refname
, strerror(last_errno
));
981 * If the ref did not exist and we are creating it, make sure
982 * there is no existing packed ref whose name begins with our
983 * refname, nor a packed ref whose name is a proper prefix of
986 if (is_null_oid(&lock
->old_oid
) &&
987 refs_verify_refname_available(refs
->packed_ref_store
, refname
,
988 extras
, skip
, err
)) {
989 last_errno
= ENOTDIR
;
993 lock
->ref_name
= xstrdup(refname
);
995 if (raceproof_create_file(ref_file
.buf
, create_reflock
, &lock
->lk
)) {
997 unable_to_lock_message(ref_file
.buf
, errno
, err
);
1001 if (verify_lock(&refs
->base
, lock
, old_oid
, mustexist
, err
)) {
1012 strbuf_release(&ref_file
);
1017 struct ref_to_prune
{
1018 struct ref_to_prune
*next
;
1019 struct object_id oid
;
1020 char name
[FLEX_ARRAY
];
1024 REMOVE_EMPTY_PARENTS_REF
= 0x01,
1025 REMOVE_EMPTY_PARENTS_REFLOG
= 0x02
1029 * Remove empty parent directories associated with the specified
1030 * reference and/or its reflog, but spare [logs/]refs/ and immediate
1031 * subdirs. flags is a combination of REMOVE_EMPTY_PARENTS_REF and/or
1032 * REMOVE_EMPTY_PARENTS_REFLOG.
1034 static void try_remove_empty_parents(struct files_ref_store
*refs
,
1035 const char *refname
,
1038 struct strbuf buf
= STRBUF_INIT
;
1039 struct strbuf sb
= STRBUF_INIT
;
1043 strbuf_addstr(&buf
, refname
);
1045 for (i
= 0; i
< 2; i
++) { /* refs/{heads,tags,...}/ */
1046 while (*p
&& *p
!= '/')
1048 /* tolerate duplicate slashes; see check_refname_format() */
1052 q
= buf
.buf
+ buf
.len
;
1053 while (flags
& (REMOVE_EMPTY_PARENTS_REF
| REMOVE_EMPTY_PARENTS_REFLOG
)) {
1054 while (q
> p
&& *q
!= '/')
1056 while (q
> p
&& *(q
-1) == '/')
1060 strbuf_setlen(&buf
, q
- buf
.buf
);
1063 files_ref_path(refs
, &sb
, buf
.buf
);
1064 if ((flags
& REMOVE_EMPTY_PARENTS_REF
) && rmdir(sb
.buf
))
1065 flags
&= ~REMOVE_EMPTY_PARENTS_REF
;
1068 files_reflog_path(refs
, &sb
, buf
.buf
);
1069 if ((flags
& REMOVE_EMPTY_PARENTS_REFLOG
) && rmdir(sb
.buf
))
1070 flags
&= ~REMOVE_EMPTY_PARENTS_REFLOG
;
1072 strbuf_release(&buf
);
1073 strbuf_release(&sb
);
1076 /* make sure nobody touched the ref, and unlink */
1077 static void prune_ref(struct files_ref_store
*refs
, struct ref_to_prune
*r
)
1079 struct ref_transaction
*transaction
;
1080 struct strbuf err
= STRBUF_INIT
;
1083 if (check_refname_format(r
->name
, 0))
1086 transaction
= ref_store_transaction_begin(&refs
->base
, &err
);
1089 ref_transaction_add_update(
1090 transaction
, r
->name
,
1091 REF_NO_DEREF
| REF_HAVE_NEW
| REF_HAVE_OLD
| REF_IS_PRUNING
,
1092 &null_oid
, &r
->oid
, NULL
);
1093 if (ref_transaction_commit(transaction
, &err
))
1100 error("%s", err
.buf
);
1101 strbuf_release(&err
);
1102 ref_transaction_free(transaction
);
1107 * Prune the loose versions of the references in the linked list
1108 * `*refs_to_prune`, freeing the entries in the list as we go.
1110 static void prune_refs(struct files_ref_store
*refs
, struct ref_to_prune
**refs_to_prune
)
1112 while (*refs_to_prune
) {
1113 struct ref_to_prune
*r
= *refs_to_prune
;
1114 *refs_to_prune
= r
->next
;
1121 * Return true if the specified reference should be packed.
1123 static int should_pack_ref(const char *refname
,
1124 const struct object_id
*oid
, unsigned int ref_flags
,
1125 unsigned int pack_flags
)
1127 /* Do not pack per-worktree refs: */
1128 if (ref_type(refname
) != REF_TYPE_NORMAL
)
1131 /* Do not pack non-tags unless PACK_REFS_ALL is set: */
1132 if (!(pack_flags
& PACK_REFS_ALL
) && !starts_with(refname
, "refs/tags/"))
1135 /* Do not pack symbolic refs: */
1136 if (ref_flags
& REF_ISSYMREF
)
1139 /* Do not pack broken refs: */
1140 if (!ref_resolves_to_object(refname
, oid
, ref_flags
))
1146 static int files_pack_refs(struct ref_store
*ref_store
, unsigned int flags
)
1148 struct files_ref_store
*refs
=
1149 files_downcast(ref_store
, REF_STORE_WRITE
| REF_STORE_ODB
,
1151 struct ref_iterator
*iter
;
1153 struct ref_to_prune
*refs_to_prune
= NULL
;
1154 struct strbuf err
= STRBUF_INIT
;
1155 struct ref_transaction
*transaction
;
1157 transaction
= ref_store_transaction_begin(refs
->packed_ref_store
, &err
);
1161 packed_refs_lock(refs
->packed_ref_store
, LOCK_DIE_ON_ERROR
, &err
);
1163 iter
= cache_ref_iterator_begin(get_loose_ref_cache(refs
), NULL
, 0);
1164 while ((ok
= ref_iterator_advance(iter
)) == ITER_OK
) {
1166 * If the loose reference can be packed, add an entry
1167 * in the packed ref cache. If the reference should be
1168 * pruned, also add it to refs_to_prune.
1170 if (!should_pack_ref(iter
->refname
, iter
->oid
, iter
->flags
,
1175 * Add a reference creation for this reference to the
1176 * packed-refs transaction:
1178 if (ref_transaction_update(transaction
, iter
->refname
,
1180 REF_NO_DEREF
, NULL
, &err
))
1181 die("failure preparing to create packed reference %s: %s",
1182 iter
->refname
, err
.buf
);
1184 /* Schedule the loose reference for pruning if requested. */
1185 if ((flags
& PACK_REFS_PRUNE
)) {
1186 struct ref_to_prune
*n
;
1187 FLEX_ALLOC_STR(n
, name
, iter
->refname
);
1188 oidcpy(&n
->oid
, iter
->oid
);
1189 n
->next
= refs_to_prune
;
1193 if (ok
!= ITER_DONE
)
1194 die("error while iterating over references");
1196 if (ref_transaction_commit(transaction
, &err
))
1197 die("unable to write new packed-refs: %s", err
.buf
);
1199 ref_transaction_free(transaction
);
1201 packed_refs_unlock(refs
->packed_ref_store
);
1203 prune_refs(refs
, &refs_to_prune
);
1204 strbuf_release(&err
);
1208 static int files_delete_refs(struct ref_store
*ref_store
, const char *msg
,
1209 struct string_list
*refnames
, unsigned int flags
)
1211 struct files_ref_store
*refs
=
1212 files_downcast(ref_store
, REF_STORE_WRITE
, "delete_refs");
1213 struct strbuf err
= STRBUF_INIT
;
1219 if (packed_refs_lock(refs
->packed_ref_store
, 0, &err
))
1222 if (refs_delete_refs(refs
->packed_ref_store
, msg
, refnames
, flags
)) {
1223 packed_refs_unlock(refs
->packed_ref_store
);
1227 packed_refs_unlock(refs
->packed_ref_store
);
1229 for (i
= 0; i
< refnames
->nr
; i
++) {
1230 const char *refname
= refnames
->items
[i
].string
;
1232 if (refs_delete_ref(&refs
->base
, msg
, refname
, NULL
, flags
))
1233 result
|= error(_("could not remove reference %s"), refname
);
1236 strbuf_release(&err
);
1241 * If we failed to rewrite the packed-refs file, then it is
1242 * unsafe to try to remove loose refs, because doing so might
1243 * expose an obsolete packed value for a reference that might
1244 * even point at an object that has been garbage collected.
1246 if (refnames
->nr
== 1)
1247 error(_("could not delete reference %s: %s"),
1248 refnames
->items
[0].string
, err
.buf
);
1250 error(_("could not delete references: %s"), err
.buf
);
1252 strbuf_release(&err
);
1257 * People using contrib's git-new-workdir have .git/logs/refs ->
1258 * /some/other/path/.git/logs/refs, and that may live on another device.
1260 * IOW, to avoid cross device rename errors, the temporary renamed log must
1261 * live into logs/refs.
1263 #define TMP_RENAMED_LOG "refs/.tmp-renamed-log"
1266 const char *tmp_renamed_log
;
1270 static int rename_tmp_log_callback(const char *path
, void *cb_data
)
1272 struct rename_cb
*cb
= cb_data
;
1274 if (rename(cb
->tmp_renamed_log
, path
)) {
1276 * rename(a, b) when b is an existing directory ought
1277 * to result in ISDIR, but Solaris 5.8 gives ENOTDIR.
1278 * Sheesh. Record the true errno for error reporting,
1279 * but report EISDIR to raceproof_create_file() so
1280 * that it knows to retry.
1282 cb
->true_errno
= errno
;
1283 if (errno
== ENOTDIR
)
1291 static int rename_tmp_log(struct files_ref_store
*refs
, const char *newrefname
)
1293 struct strbuf path
= STRBUF_INIT
;
1294 struct strbuf tmp
= STRBUF_INIT
;
1295 struct rename_cb cb
;
1298 files_reflog_path(refs
, &path
, newrefname
);
1299 files_reflog_path(refs
, &tmp
, TMP_RENAMED_LOG
);
1300 cb
.tmp_renamed_log
= tmp
.buf
;
1301 ret
= raceproof_create_file(path
.buf
, rename_tmp_log_callback
, &cb
);
1303 if (errno
== EISDIR
)
1304 error("directory not empty: %s", path
.buf
);
1306 error("unable to move logfile %s to %s: %s",
1308 strerror(cb
.true_errno
));
1311 strbuf_release(&path
);
1312 strbuf_release(&tmp
);
1316 static int write_ref_to_lockfile(struct ref_lock
*lock
,
1317 const struct object_id
*oid
, struct strbuf
*err
);
1318 static int commit_ref_update(struct files_ref_store
*refs
,
1319 struct ref_lock
*lock
,
1320 const struct object_id
*oid
, const char *logmsg
,
1321 struct strbuf
*err
);
1323 static int files_copy_or_rename_ref(struct ref_store
*ref_store
,
1324 const char *oldrefname
, const char *newrefname
,
1325 const char *logmsg
, int copy
)
1327 struct files_ref_store
*refs
=
1328 files_downcast(ref_store
, REF_STORE_WRITE
, "rename_ref");
1329 struct object_id oid
, orig_oid
;
1330 int flag
= 0, logmoved
= 0;
1331 struct ref_lock
*lock
;
1332 struct stat loginfo
;
1333 struct strbuf sb_oldref
= STRBUF_INIT
;
1334 struct strbuf sb_newref
= STRBUF_INIT
;
1335 struct strbuf tmp_renamed_log
= STRBUF_INIT
;
1337 struct strbuf err
= STRBUF_INIT
;
1339 files_reflog_path(refs
, &sb_oldref
, oldrefname
);
1340 files_reflog_path(refs
, &sb_newref
, newrefname
);
1341 files_reflog_path(refs
, &tmp_renamed_log
, TMP_RENAMED_LOG
);
1343 log
= !lstat(sb_oldref
.buf
, &loginfo
);
1344 if (log
&& S_ISLNK(loginfo
.st_mode
)) {
1345 ret
= error("reflog for %s is a symlink", oldrefname
);
1349 if (!refs_resolve_ref_unsafe(&refs
->base
, oldrefname
,
1350 RESOLVE_REF_READING
| RESOLVE_REF_NO_RECURSE
,
1351 &orig_oid
, &flag
)) {
1352 ret
= error("refname %s not found", oldrefname
);
1356 if (flag
& REF_ISSYMREF
) {
1358 ret
= error("refname %s is a symbolic ref, copying it is not supported",
1361 ret
= error("refname %s is a symbolic ref, renaming it is not supported",
1365 if (!refs_rename_ref_available(&refs
->base
, oldrefname
, newrefname
)) {
1370 if (!copy
&& log
&& rename(sb_oldref
.buf
, tmp_renamed_log
.buf
)) {
1371 ret
= error("unable to move logfile logs/%s to logs/"TMP_RENAMED_LOG
": %s",
1372 oldrefname
, strerror(errno
));
1376 if (copy
&& log
&& copy_file(tmp_renamed_log
.buf
, sb_oldref
.buf
, 0644)) {
1377 ret
= error("unable to copy logfile logs/%s to logs/"TMP_RENAMED_LOG
": %s",
1378 oldrefname
, strerror(errno
));
1382 if (!copy
&& refs_delete_ref(&refs
->base
, logmsg
, oldrefname
,
1383 &orig_oid
, REF_NO_DEREF
)) {
1384 error("unable to delete old %s", oldrefname
);
1389 * Since we are doing a shallow lookup, oid is not the
1390 * correct value to pass to delete_ref as old_oid. But that
1391 * doesn't matter, because an old_oid check wouldn't add to
1392 * the safety anyway; we want to delete the reference whatever
1393 * its current value.
1395 if (!copy
&& !refs_read_ref_full(&refs
->base
, newrefname
,
1396 RESOLVE_REF_READING
| RESOLVE_REF_NO_RECURSE
,
1398 refs_delete_ref(&refs
->base
, NULL
, newrefname
,
1399 NULL
, REF_NO_DEREF
)) {
1400 if (errno
== EISDIR
) {
1401 struct strbuf path
= STRBUF_INIT
;
1404 files_ref_path(refs
, &path
, newrefname
);
1405 result
= remove_empty_directories(&path
);
1406 strbuf_release(&path
);
1409 error("Directory not empty: %s", newrefname
);
1413 error("unable to delete existing %s", newrefname
);
1418 if (log
&& rename_tmp_log(refs
, newrefname
))
1423 lock
= lock_ref_oid_basic(refs
, newrefname
, NULL
, NULL
, NULL
,
1424 REF_NO_DEREF
, NULL
, &err
);
1427 error("unable to copy '%s' to '%s': %s", oldrefname
, newrefname
, err
.buf
);
1429 error("unable to rename '%s' to '%s': %s", oldrefname
, newrefname
, err
.buf
);
1430 strbuf_release(&err
);
1433 oidcpy(&lock
->old_oid
, &orig_oid
);
1435 if (write_ref_to_lockfile(lock
, &orig_oid
, &err
) ||
1436 commit_ref_update(refs
, lock
, &orig_oid
, logmsg
, &err
)) {
1437 error("unable to write current sha1 into %s: %s", newrefname
, err
.buf
);
1438 strbuf_release(&err
);
1446 lock
= lock_ref_oid_basic(refs
, oldrefname
, NULL
, NULL
, NULL
,
1447 REF_NO_DEREF
, NULL
, &err
);
1449 error("unable to lock %s for rollback: %s", oldrefname
, err
.buf
);
1450 strbuf_release(&err
);
1454 flag
= log_all_ref_updates
;
1455 log_all_ref_updates
= LOG_REFS_NONE
;
1456 if (write_ref_to_lockfile(lock
, &orig_oid
, &err
) ||
1457 commit_ref_update(refs
, lock
, &orig_oid
, NULL
, &err
)) {
1458 error("unable to write current sha1 into %s: %s", oldrefname
, err
.buf
);
1459 strbuf_release(&err
);
1461 log_all_ref_updates
= flag
;
1464 if (logmoved
&& rename(sb_newref
.buf
, sb_oldref
.buf
))
1465 error("unable to restore logfile %s from %s: %s",
1466 oldrefname
, newrefname
, strerror(errno
));
1467 if (!logmoved
&& log
&&
1468 rename(tmp_renamed_log
.buf
, sb_oldref
.buf
))
1469 error("unable to restore logfile %s from logs/"TMP_RENAMED_LOG
": %s",
1470 oldrefname
, strerror(errno
));
1473 strbuf_release(&sb_newref
);
1474 strbuf_release(&sb_oldref
);
1475 strbuf_release(&tmp_renamed_log
);
1480 static int files_rename_ref(struct ref_store
*ref_store
,
1481 const char *oldrefname
, const char *newrefname
,
1484 return files_copy_or_rename_ref(ref_store
, oldrefname
,
1485 newrefname
, logmsg
, 0);
1488 static int files_copy_ref(struct ref_store
*ref_store
,
1489 const char *oldrefname
, const char *newrefname
,
1492 return files_copy_or_rename_ref(ref_store
, oldrefname
,
1493 newrefname
, logmsg
, 1);
1496 static int close_ref_gently(struct ref_lock
*lock
)
1498 if (close_lock_file_gently(&lock
->lk
))
1503 static int commit_ref(struct ref_lock
*lock
)
1505 char *path
= get_locked_file_path(&lock
->lk
);
1508 if (!lstat(path
, &st
) && S_ISDIR(st
.st_mode
)) {
1510 * There is a directory at the path we want to rename
1511 * the lockfile to. Hopefully it is empty; try to
1514 size_t len
= strlen(path
);
1515 struct strbuf sb_path
= STRBUF_INIT
;
1517 strbuf_attach(&sb_path
, path
, len
, len
);
1520 * If this fails, commit_lock_file() will also fail
1521 * and will report the problem.
1523 remove_empty_directories(&sb_path
);
1524 strbuf_release(&sb_path
);
1529 if (commit_lock_file(&lock
->lk
))
1534 static int open_or_create_logfile(const char *path
, void *cb
)
1538 *fd
= open(path
, O_APPEND
| O_WRONLY
| O_CREAT
, 0666);
1539 return (*fd
< 0) ? -1 : 0;
1543 * Create a reflog for a ref. If force_create = 0, only create the
1544 * reflog for certain refs (those for which should_autocreate_reflog
1545 * returns non-zero). Otherwise, create it regardless of the reference
1546 * name. If the logfile already existed or was created, return 0 and
1547 * set *logfd to the file descriptor opened for appending to the file.
1548 * If no logfile exists and we decided not to create one, return 0 and
1549 * set *logfd to -1. On failure, fill in *err, set *logfd to -1, and
1552 static int log_ref_setup(struct files_ref_store
*refs
,
1553 const char *refname
, int force_create
,
1554 int *logfd
, struct strbuf
*err
)
1556 struct strbuf logfile_sb
= STRBUF_INIT
;
1559 files_reflog_path(refs
, &logfile_sb
, refname
);
1560 logfile
= strbuf_detach(&logfile_sb
, NULL
);
1562 if (force_create
|| should_autocreate_reflog(refname
)) {
1563 if (raceproof_create_file(logfile
, open_or_create_logfile
, logfd
)) {
1564 if (errno
== ENOENT
)
1565 strbuf_addf(err
, "unable to create directory for '%s': "
1566 "%s", logfile
, strerror(errno
));
1567 else if (errno
== EISDIR
)
1568 strbuf_addf(err
, "there are still logs under '%s'",
1571 strbuf_addf(err
, "unable to append to '%s': %s",
1572 logfile
, strerror(errno
));
1577 *logfd
= open(logfile
, O_APPEND
| O_WRONLY
, 0666);
1579 if (errno
== ENOENT
|| errno
== EISDIR
) {
1581 * The logfile doesn't already exist,
1582 * but that is not an error; it only
1583 * means that we won't write log
1588 strbuf_addf(err
, "unable to append to '%s': %s",
1589 logfile
, strerror(errno
));
1596 adjust_shared_perm(logfile
);
1606 static int files_create_reflog(struct ref_store
*ref_store
,
1607 const char *refname
, int force_create
,
1610 struct files_ref_store
*refs
=
1611 files_downcast(ref_store
, REF_STORE_WRITE
, "create_reflog");
1614 if (log_ref_setup(refs
, refname
, force_create
, &fd
, err
))
1623 static int log_ref_write_fd(int fd
, const struct object_id
*old_oid
,
1624 const struct object_id
*new_oid
,
1625 const char *committer
, const char *msg
)
1627 struct strbuf sb
= STRBUF_INIT
;
1630 strbuf_addf(&sb
, "%s %s %s", oid_to_hex(old_oid
), oid_to_hex(new_oid
), committer
);
1632 copy_reflog_msg(&sb
, msg
);
1633 strbuf_addch(&sb
, '\n');
1634 if (write_in_full(fd
, sb
.buf
, sb
.len
) < 0)
1636 strbuf_release(&sb
);
1640 static int files_log_ref_write(struct files_ref_store
*refs
,
1641 const char *refname
, const struct object_id
*old_oid
,
1642 const struct object_id
*new_oid
, const char *msg
,
1643 int flags
, struct strbuf
*err
)
1647 if (log_all_ref_updates
== LOG_REFS_UNSET
)
1648 log_all_ref_updates
= is_bare_repository() ? LOG_REFS_NONE
: LOG_REFS_NORMAL
;
1650 result
= log_ref_setup(refs
, refname
,
1651 flags
& REF_FORCE_CREATE_REFLOG
,
1659 result
= log_ref_write_fd(logfd
, old_oid
, new_oid
,
1660 git_committer_info(0), msg
);
1662 struct strbuf sb
= STRBUF_INIT
;
1663 int save_errno
= errno
;
1665 files_reflog_path(refs
, &sb
, refname
);
1666 strbuf_addf(err
, "unable to append to '%s': %s",
1667 sb
.buf
, strerror(save_errno
));
1668 strbuf_release(&sb
);
1673 struct strbuf sb
= STRBUF_INIT
;
1674 int save_errno
= errno
;
1676 files_reflog_path(refs
, &sb
, refname
);
1677 strbuf_addf(err
, "unable to append to '%s': %s",
1678 sb
.buf
, strerror(save_errno
));
1679 strbuf_release(&sb
);
1686 * Write oid into the open lockfile, then close the lockfile. On
1687 * errors, rollback the lockfile, fill in *err and return -1.
1689 static int write_ref_to_lockfile(struct ref_lock
*lock
,
1690 const struct object_id
*oid
, struct strbuf
*err
)
1692 static char term
= '\n';
1696 o
= parse_object(the_repository
, oid
);
1699 "trying to write ref '%s' with nonexistent object %s",
1700 lock
->ref_name
, oid_to_hex(oid
));
1704 if (o
->type
!= OBJ_COMMIT
&& is_branch(lock
->ref_name
)) {
1706 "trying to write non-commit object %s to branch '%s'",
1707 oid_to_hex(oid
), lock
->ref_name
);
1711 fd
= get_lock_file_fd(&lock
->lk
);
1712 if (write_in_full(fd
, oid_to_hex(oid
), the_hash_algo
->hexsz
) < 0 ||
1713 write_in_full(fd
, &term
, 1) < 0 ||
1714 close_ref_gently(lock
) < 0) {
1716 "couldn't write '%s'", get_lock_file_path(&lock
->lk
));
1724 * Commit a change to a loose reference that has already been written
1725 * to the loose reference lockfile. Also update the reflogs if
1726 * necessary, using the specified lockmsg (which can be NULL).
1728 static int commit_ref_update(struct files_ref_store
*refs
,
1729 struct ref_lock
*lock
,
1730 const struct object_id
*oid
, const char *logmsg
,
1733 files_assert_main_repository(refs
, "commit_ref_update");
1735 clear_loose_ref_cache(refs
);
1736 if (files_log_ref_write(refs
, lock
->ref_name
,
1737 &lock
->old_oid
, oid
,
1739 char *old_msg
= strbuf_detach(err
, NULL
);
1740 strbuf_addf(err
, "cannot update the ref '%s': %s",
1741 lock
->ref_name
, old_msg
);
1747 if (strcmp(lock
->ref_name
, "HEAD") != 0) {
1749 * Special hack: If a branch is updated directly and HEAD
1750 * points to it (may happen on the remote side of a push
1751 * for example) then logically the HEAD reflog should be
1753 * A generic solution implies reverse symref information,
1754 * but finding all symrefs pointing to the given branch
1755 * would be rather costly for this rare event (the direct
1756 * update of a branch) to be worth it. So let's cheat and
1757 * check with HEAD only which should cover 99% of all usage
1758 * scenarios (even 100% of the default ones).
1761 const char *head_ref
;
1763 head_ref
= refs_resolve_ref_unsafe(&refs
->base
, "HEAD",
1764 RESOLVE_REF_READING
,
1766 if (head_ref
&& (head_flag
& REF_ISSYMREF
) &&
1767 !strcmp(head_ref
, lock
->ref_name
)) {
1768 struct strbuf log_err
= STRBUF_INIT
;
1769 if (files_log_ref_write(refs
, "HEAD",
1770 &lock
->old_oid
, oid
,
1771 logmsg
, 0, &log_err
)) {
1772 error("%s", log_err
.buf
);
1773 strbuf_release(&log_err
);
1778 if (commit_ref(lock
)) {
1779 strbuf_addf(err
, "couldn't set '%s'", lock
->ref_name
);
1788 static int create_ref_symlink(struct ref_lock
*lock
, const char *target
)
1791 #ifndef NO_SYMLINK_HEAD
1792 char *ref_path
= get_locked_file_path(&lock
->lk
);
1794 ret
= symlink(target
, ref_path
);
1798 fprintf(stderr
, "no symlink - falling back to symbolic ref\n");
1803 static void update_symref_reflog(struct files_ref_store
*refs
,
1804 struct ref_lock
*lock
, const char *refname
,
1805 const char *target
, const char *logmsg
)
1807 struct strbuf err
= STRBUF_INIT
;
1808 struct object_id new_oid
;
1810 !refs_read_ref_full(&refs
->base
, target
,
1811 RESOLVE_REF_READING
, &new_oid
, NULL
) &&
1812 files_log_ref_write(refs
, refname
, &lock
->old_oid
,
1813 &new_oid
, logmsg
, 0, &err
)) {
1814 error("%s", err
.buf
);
1815 strbuf_release(&err
);
1819 static int create_symref_locked(struct files_ref_store
*refs
,
1820 struct ref_lock
*lock
, const char *refname
,
1821 const char *target
, const char *logmsg
)
1823 if (prefer_symlink_refs
&& !create_ref_symlink(lock
, target
)) {
1824 update_symref_reflog(refs
, lock
, refname
, target
, logmsg
);
1828 if (!fdopen_lock_file(&lock
->lk
, "w"))
1829 return error("unable to fdopen %s: %s",
1830 lock
->lk
.tempfile
->filename
.buf
, strerror(errno
));
1832 update_symref_reflog(refs
, lock
, refname
, target
, logmsg
);
1834 /* no error check; commit_ref will check ferror */
1835 fprintf(lock
->lk
.tempfile
->fp
, "ref: %s\n", target
);
1836 if (commit_ref(lock
) < 0)
1837 return error("unable to write symref for %s: %s", refname
,
1842 static int files_create_symref(struct ref_store
*ref_store
,
1843 const char *refname
, const char *target
,
1846 struct files_ref_store
*refs
=
1847 files_downcast(ref_store
, REF_STORE_WRITE
, "create_symref");
1848 struct strbuf err
= STRBUF_INIT
;
1849 struct ref_lock
*lock
;
1852 lock
= lock_ref_oid_basic(refs
, refname
, NULL
,
1853 NULL
, NULL
, REF_NO_DEREF
, NULL
,
1856 error("%s", err
.buf
);
1857 strbuf_release(&err
);
1861 ret
= create_symref_locked(refs
, lock
, refname
, target
, logmsg
);
1866 static int files_reflog_exists(struct ref_store
*ref_store
,
1867 const char *refname
)
1869 struct files_ref_store
*refs
=
1870 files_downcast(ref_store
, REF_STORE_READ
, "reflog_exists");
1871 struct strbuf sb
= STRBUF_INIT
;
1875 files_reflog_path(refs
, &sb
, refname
);
1876 ret
= !lstat(sb
.buf
, &st
) && S_ISREG(st
.st_mode
);
1877 strbuf_release(&sb
);
1881 static int files_delete_reflog(struct ref_store
*ref_store
,
1882 const char *refname
)
1884 struct files_ref_store
*refs
=
1885 files_downcast(ref_store
, REF_STORE_WRITE
, "delete_reflog");
1886 struct strbuf sb
= STRBUF_INIT
;
1889 files_reflog_path(refs
, &sb
, refname
);
1890 ret
= remove_path(sb
.buf
);
1891 strbuf_release(&sb
);
1895 static int show_one_reflog_ent(struct strbuf
*sb
, each_reflog_ent_fn fn
, void *cb_data
)
1897 struct object_id ooid
, noid
;
1898 char *email_end
, *message
;
1899 timestamp_t timestamp
;
1901 const char *p
= sb
->buf
;
1903 /* old SP new SP name <email> SP time TAB msg LF */
1904 if (!sb
->len
|| sb
->buf
[sb
->len
- 1] != '\n' ||
1905 parse_oid_hex(p
, &ooid
, &p
) || *p
++ != ' ' ||
1906 parse_oid_hex(p
, &noid
, &p
) || *p
++ != ' ' ||
1907 !(email_end
= strchr(p
, '>')) ||
1908 email_end
[1] != ' ' ||
1909 !(timestamp
= parse_timestamp(email_end
+ 2, &message
, 10)) ||
1910 !message
|| message
[0] != ' ' ||
1911 (message
[1] != '+' && message
[1] != '-') ||
1912 !isdigit(message
[2]) || !isdigit(message
[3]) ||
1913 !isdigit(message
[4]) || !isdigit(message
[5]))
1914 return 0; /* corrupt? */
1915 email_end
[1] = '\0';
1916 tz
= strtol(message
+ 1, NULL
, 10);
1917 if (message
[6] != '\t')
1921 return fn(&ooid
, &noid
, p
, timestamp
, tz
, message
, cb_data
);
1924 static char *find_beginning_of_line(char *bob
, char *scan
)
1926 while (bob
< scan
&& *(--scan
) != '\n')
1927 ; /* keep scanning backwards */
1929 * Return either beginning of the buffer, or LF at the end of
1930 * the previous line.
1935 static int files_for_each_reflog_ent_reverse(struct ref_store
*ref_store
,
1936 const char *refname
,
1937 each_reflog_ent_fn fn
,
1940 struct files_ref_store
*refs
=
1941 files_downcast(ref_store
, REF_STORE_READ
,
1942 "for_each_reflog_ent_reverse");
1943 struct strbuf sb
= STRBUF_INIT
;
1946 int ret
= 0, at_tail
= 1;
1948 files_reflog_path(refs
, &sb
, refname
);
1949 logfp
= fopen(sb
.buf
, "r");
1950 strbuf_release(&sb
);
1954 /* Jump to the end */
1955 if (fseek(logfp
, 0, SEEK_END
) < 0)
1956 ret
= error("cannot seek back reflog for %s: %s",
1957 refname
, strerror(errno
));
1959 while (!ret
&& 0 < pos
) {
1965 /* Fill next block from the end */
1966 cnt
= (sizeof(buf
) < pos
) ? sizeof(buf
) : pos
;
1967 if (fseek(logfp
, pos
- cnt
, SEEK_SET
)) {
1968 ret
= error("cannot seek back reflog for %s: %s",
1969 refname
, strerror(errno
));
1972 nread
= fread(buf
, cnt
, 1, logfp
);
1974 ret
= error("cannot read %d bytes from reflog for %s: %s",
1975 cnt
, refname
, strerror(errno
));
1980 scanp
= endp
= buf
+ cnt
;
1981 if (at_tail
&& scanp
[-1] == '\n')
1982 /* Looking at the final LF at the end of the file */
1986 while (buf
< scanp
) {
1988 * terminating LF of the previous line, or the beginning
1993 bp
= find_beginning_of_line(buf
, scanp
);
1997 * The newline is the end of the previous line,
1998 * so we know we have complete line starting
1999 * at (bp + 1). Prefix it onto any prior data
2000 * we collected for the line and process it.
2002 strbuf_splice(&sb
, 0, 0, bp
+ 1, endp
- (bp
+ 1));
2005 ret
= show_one_reflog_ent(&sb
, fn
, cb_data
);
2011 * We are at the start of the buffer, and the
2012 * start of the file; there is no previous
2013 * line, and we have everything for this one.
2014 * Process it, and we can end the loop.
2016 strbuf_splice(&sb
, 0, 0, buf
, endp
- buf
);
2017 ret
= show_one_reflog_ent(&sb
, fn
, cb_data
);
2024 * We are at the start of the buffer, and there
2025 * is more file to read backwards. Which means
2026 * we are in the middle of a line. Note that we
2027 * may get here even if *bp was a newline; that
2028 * just means we are at the exact end of the
2029 * previous line, rather than some spot in the
2032 * Save away what we have to be combined with
2033 * the data from the next read.
2035 strbuf_splice(&sb
, 0, 0, buf
, endp
- buf
);
2042 BUG("reverse reflog parser had leftover data");
2045 strbuf_release(&sb
);
2049 static int files_for_each_reflog_ent(struct ref_store
*ref_store
,
2050 const char *refname
,
2051 each_reflog_ent_fn fn
, void *cb_data
)
2053 struct files_ref_store
*refs
=
2054 files_downcast(ref_store
, REF_STORE_READ
,
2055 "for_each_reflog_ent");
2057 struct strbuf sb
= STRBUF_INIT
;
2060 files_reflog_path(refs
, &sb
, refname
);
2061 logfp
= fopen(sb
.buf
, "r");
2062 strbuf_release(&sb
);
2066 while (!ret
&& !strbuf_getwholeline(&sb
, logfp
, '\n'))
2067 ret
= show_one_reflog_ent(&sb
, fn
, cb_data
);
2069 strbuf_release(&sb
);
2073 struct files_reflog_iterator
{
2074 struct ref_iterator base
;
2076 struct ref_store
*ref_store
;
2077 struct dir_iterator
*dir_iterator
;
2078 struct object_id oid
;
2081 static int files_reflog_iterator_advance(struct ref_iterator
*ref_iterator
)
2083 struct files_reflog_iterator
*iter
=
2084 (struct files_reflog_iterator
*)ref_iterator
;
2085 struct dir_iterator
*diter
= iter
->dir_iterator
;
2088 while ((ok
= dir_iterator_advance(diter
)) == ITER_OK
) {
2091 if (!S_ISREG(diter
->st
.st_mode
))
2093 if (diter
->basename
[0] == '.')
2095 if (ends_with(diter
->basename
, ".lock"))
2098 if (refs_read_ref_full(iter
->ref_store
,
2099 diter
->relative_path
, 0,
2100 &iter
->oid
, &flags
)) {
2101 error("bad ref for %s", diter
->path
.buf
);
2105 iter
->base
.refname
= diter
->relative_path
;
2106 iter
->base
.oid
= &iter
->oid
;
2107 iter
->base
.flags
= flags
;
2111 iter
->dir_iterator
= NULL
;
2112 if (ref_iterator_abort(ref_iterator
) == ITER_ERROR
)
2117 static int files_reflog_iterator_peel(struct ref_iterator
*ref_iterator
,
2118 struct object_id
*peeled
)
2120 BUG("ref_iterator_peel() called for reflog_iterator");
2123 static int files_reflog_iterator_abort(struct ref_iterator
*ref_iterator
)
2125 struct files_reflog_iterator
*iter
=
2126 (struct files_reflog_iterator
*)ref_iterator
;
2129 if (iter
->dir_iterator
)
2130 ok
= dir_iterator_abort(iter
->dir_iterator
);
2132 base_ref_iterator_free(ref_iterator
);
2136 static struct ref_iterator_vtable files_reflog_iterator_vtable
= {
2137 files_reflog_iterator_advance
,
2138 files_reflog_iterator_peel
,
2139 files_reflog_iterator_abort
2142 static struct ref_iterator
*reflog_iterator_begin(struct ref_store
*ref_store
,
2145 struct files_reflog_iterator
*iter
= xcalloc(1, sizeof(*iter
));
2146 struct ref_iterator
*ref_iterator
= &iter
->base
;
2147 struct strbuf sb
= STRBUF_INIT
;
2149 base_ref_iterator_init(ref_iterator
, &files_reflog_iterator_vtable
, 0);
2150 strbuf_addf(&sb
, "%s/logs", gitdir
);
2151 iter
->dir_iterator
= dir_iterator_begin(sb
.buf
);
2152 iter
->ref_store
= ref_store
;
2153 strbuf_release(&sb
);
2155 return ref_iterator
;
2158 static enum iterator_selection
reflog_iterator_select(
2159 struct ref_iterator
*iter_worktree
,
2160 struct ref_iterator
*iter_common
,
2163 if (iter_worktree
) {
2165 * We're a bit loose here. We probably should ignore
2166 * common refs if they are accidentally added as
2167 * per-worktree refs.
2169 return ITER_SELECT_0
;
2170 } else if (iter_common
) {
2171 if (ref_type(iter_common
->refname
) == REF_TYPE_NORMAL
)
2172 return ITER_SELECT_1
;
2175 * The main ref store may contain main worktree's
2176 * per-worktree refs, which should be ignored
2183 static struct ref_iterator
*files_reflog_iterator_begin(struct ref_store
*ref_store
)
2185 struct files_ref_store
*refs
=
2186 files_downcast(ref_store
, REF_STORE_READ
,
2187 "reflog_iterator_begin");
2189 if (!strcmp(refs
->gitdir
, refs
->gitcommondir
)) {
2190 return reflog_iterator_begin(ref_store
, refs
->gitcommondir
);
2192 return merge_ref_iterator_begin(
2194 reflog_iterator_begin(ref_store
, refs
->gitdir
),
2195 reflog_iterator_begin(ref_store
, refs
->gitcommondir
),
2196 reflog_iterator_select
, refs
);
2201 * If update is a direct update of head_ref (the reference pointed to
2202 * by HEAD), then add an extra REF_LOG_ONLY update for HEAD.
2204 static int split_head_update(struct ref_update
*update
,
2205 struct ref_transaction
*transaction
,
2206 const char *head_ref
,
2207 struct string_list
*affected_refnames
,
2210 struct string_list_item
*item
;
2211 struct ref_update
*new_update
;
2213 if ((update
->flags
& REF_LOG_ONLY
) ||
2214 (update
->flags
& REF_IS_PRUNING
) ||
2215 (update
->flags
& REF_UPDATE_VIA_HEAD
))
2218 if (strcmp(update
->refname
, head_ref
))
2222 * First make sure that HEAD is not already in the
2223 * transaction. This check is O(lg N) in the transaction
2224 * size, but it happens at most once per transaction.
2226 if (string_list_has_string(affected_refnames
, "HEAD")) {
2227 /* An entry already existed */
2229 "multiple updates for 'HEAD' (including one "
2230 "via its referent '%s') are not allowed",
2232 return TRANSACTION_NAME_CONFLICT
;
2235 new_update
= ref_transaction_add_update(
2236 transaction
, "HEAD",
2237 update
->flags
| REF_LOG_ONLY
| REF_NO_DEREF
,
2238 &update
->new_oid
, &update
->old_oid
,
2242 * Add "HEAD". This insertion is O(N) in the transaction
2243 * size, but it happens at most once per transaction.
2244 * Add new_update->refname instead of a literal "HEAD".
2246 if (strcmp(new_update
->refname
, "HEAD"))
2247 BUG("%s unexpectedly not 'HEAD'", new_update
->refname
);
2248 item
= string_list_insert(affected_refnames
, new_update
->refname
);
2249 item
->util
= new_update
;
2255 * update is for a symref that points at referent and doesn't have
2256 * REF_NO_DEREF set. Split it into two updates:
2257 * - The original update, but with REF_LOG_ONLY and REF_NO_DEREF set
2258 * - A new, separate update for the referent reference
2259 * Note that the new update will itself be subject to splitting when
2260 * the iteration gets to it.
2262 static int split_symref_update(struct files_ref_store
*refs
,
2263 struct ref_update
*update
,
2264 const char *referent
,
2265 struct ref_transaction
*transaction
,
2266 struct string_list
*affected_refnames
,
2269 struct string_list_item
*item
;
2270 struct ref_update
*new_update
;
2271 unsigned int new_flags
;
2274 * First make sure that referent is not already in the
2275 * transaction. This check is O(lg N) in the transaction
2276 * size, but it happens at most once per symref in a
2279 if (string_list_has_string(affected_refnames
, referent
)) {
2280 /* An entry already exists */
2282 "multiple updates for '%s' (including one "
2283 "via symref '%s') are not allowed",
2284 referent
, update
->refname
);
2285 return TRANSACTION_NAME_CONFLICT
;
2288 new_flags
= update
->flags
;
2289 if (!strcmp(update
->refname
, "HEAD")) {
2291 * Record that the new update came via HEAD, so that
2292 * when we process it, split_head_update() doesn't try
2293 * to add another reflog update for HEAD. Note that
2294 * this bit will be propagated if the new_update
2295 * itself needs to be split.
2297 new_flags
|= REF_UPDATE_VIA_HEAD
;
2300 new_update
= ref_transaction_add_update(
2301 transaction
, referent
, new_flags
,
2302 &update
->new_oid
, &update
->old_oid
,
2305 new_update
->parent_update
= update
;
2308 * Change the symbolic ref update to log only. Also, it
2309 * doesn't need to check its old OID value, as that will be
2310 * done when new_update is processed.
2312 update
->flags
|= REF_LOG_ONLY
| REF_NO_DEREF
;
2313 update
->flags
&= ~REF_HAVE_OLD
;
2316 * Add the referent. This insertion is O(N) in the transaction
2317 * size, but it happens at most once per symref in a
2318 * transaction. Make sure to add new_update->refname, which will
2319 * be valid as long as affected_refnames is in use, and NOT
2320 * referent, which might soon be freed by our caller.
2322 item
= string_list_insert(affected_refnames
, new_update
->refname
);
2324 BUG("%s unexpectedly found in affected_refnames",
2325 new_update
->refname
);
2326 item
->util
= new_update
;
2332 * Return the refname under which update was originally requested.
2334 static const char *original_update_refname(struct ref_update
*update
)
2336 while (update
->parent_update
)
2337 update
= update
->parent_update
;
2339 return update
->refname
;
2343 * Check whether the REF_HAVE_OLD and old_oid values stored in update
2344 * are consistent with oid, which is the reference's current value. If
2345 * everything is OK, return 0; otherwise, write an error message to
2346 * err and return -1.
2348 static int check_old_oid(struct ref_update
*update
, struct object_id
*oid
,
2351 if (!(update
->flags
& REF_HAVE_OLD
) ||
2352 oideq(oid
, &update
->old_oid
))
2355 if (is_null_oid(&update
->old_oid
))
2356 strbuf_addf(err
, "cannot lock ref '%s': "
2357 "reference already exists",
2358 original_update_refname(update
));
2359 else if (is_null_oid(oid
))
2360 strbuf_addf(err
, "cannot lock ref '%s': "
2361 "reference is missing but expected %s",
2362 original_update_refname(update
),
2363 oid_to_hex(&update
->old_oid
));
2365 strbuf_addf(err
, "cannot lock ref '%s': "
2366 "is at %s but expected %s",
2367 original_update_refname(update
),
2369 oid_to_hex(&update
->old_oid
));
2375 * Prepare for carrying out update:
2376 * - Lock the reference referred to by update.
2377 * - Read the reference under lock.
2378 * - Check that its old OID value (if specified) is correct, and in
2379 * any case record it in update->lock->old_oid for later use when
2380 * writing the reflog.
2381 * - If it is a symref update without REF_NO_DEREF, split it up into a
2382 * REF_LOG_ONLY update of the symref and add a separate update for
2383 * the referent to transaction.
2384 * - If it is an update of head_ref, add a corresponding REF_LOG_ONLY
2387 static int lock_ref_for_update(struct files_ref_store
*refs
,
2388 struct ref_update
*update
,
2389 struct ref_transaction
*transaction
,
2390 const char *head_ref
,
2391 struct string_list
*affected_refnames
,
2394 struct strbuf referent
= STRBUF_INIT
;
2395 int mustexist
= (update
->flags
& REF_HAVE_OLD
) &&
2396 !is_null_oid(&update
->old_oid
);
2398 struct ref_lock
*lock
;
2400 files_assert_main_repository(refs
, "lock_ref_for_update");
2402 if ((update
->flags
& REF_HAVE_NEW
) && is_null_oid(&update
->new_oid
))
2403 update
->flags
|= REF_DELETING
;
2406 ret
= split_head_update(update
, transaction
, head_ref
,
2407 affected_refnames
, err
);
2412 ret
= lock_raw_ref(refs
, update
->refname
, mustexist
,
2413 affected_refnames
, NULL
,
2415 &update
->type
, err
);
2419 reason
= strbuf_detach(err
, NULL
);
2420 strbuf_addf(err
, "cannot lock ref '%s': %s",
2421 original_update_refname(update
), reason
);
2426 update
->backend_data
= lock
;
2428 if (update
->type
& REF_ISSYMREF
) {
2429 if (update
->flags
& REF_NO_DEREF
) {
2431 * We won't be reading the referent as part of
2432 * the transaction, so we have to read it here
2433 * to record and possibly check old_oid:
2435 if (refs_read_ref_full(&refs
->base
,
2437 &lock
->old_oid
, NULL
)) {
2438 if (update
->flags
& REF_HAVE_OLD
) {
2439 strbuf_addf(err
, "cannot lock ref '%s': "
2440 "error reading reference",
2441 original_update_refname(update
));
2442 ret
= TRANSACTION_GENERIC_ERROR
;
2445 } else if (check_old_oid(update
, &lock
->old_oid
, err
)) {
2446 ret
= TRANSACTION_GENERIC_ERROR
;
2451 * Create a new update for the reference this
2452 * symref is pointing at. Also, we will record
2453 * and verify old_oid for this update as part
2454 * of processing the split-off update, so we
2455 * don't have to do it here.
2457 ret
= split_symref_update(refs
, update
,
2458 referent
.buf
, transaction
,
2459 affected_refnames
, err
);
2464 struct ref_update
*parent_update
;
2466 if (check_old_oid(update
, &lock
->old_oid
, err
)) {
2467 ret
= TRANSACTION_GENERIC_ERROR
;
2472 * If this update is happening indirectly because of a
2473 * symref update, record the old OID in the parent
2476 for (parent_update
= update
->parent_update
;
2478 parent_update
= parent_update
->parent_update
) {
2479 struct ref_lock
*parent_lock
= parent_update
->backend_data
;
2480 oidcpy(&parent_lock
->old_oid
, &lock
->old_oid
);
2484 if ((update
->flags
& REF_HAVE_NEW
) &&
2485 !(update
->flags
& REF_DELETING
) &&
2486 !(update
->flags
& REF_LOG_ONLY
)) {
2487 if (!(update
->type
& REF_ISSYMREF
) &&
2488 oideq(&lock
->old_oid
, &update
->new_oid
)) {
2490 * The reference already has the desired
2491 * value, so we don't need to write it.
2493 } else if (write_ref_to_lockfile(lock
, &update
->new_oid
,
2495 char *write_err
= strbuf_detach(err
, NULL
);
2498 * The lock was freed upon failure of
2499 * write_ref_to_lockfile():
2501 update
->backend_data
= NULL
;
2503 "cannot update ref '%s': %s",
2504 update
->refname
, write_err
);
2506 ret
= TRANSACTION_GENERIC_ERROR
;
2509 update
->flags
|= REF_NEEDS_COMMIT
;
2512 if (!(update
->flags
& REF_NEEDS_COMMIT
)) {
2514 * We didn't call write_ref_to_lockfile(), so
2515 * the lockfile is still open. Close it to
2516 * free up the file descriptor:
2518 if (close_ref_gently(lock
)) {
2519 strbuf_addf(err
, "couldn't close '%s.lock'",
2521 ret
= TRANSACTION_GENERIC_ERROR
;
2527 strbuf_release(&referent
);
2531 struct files_transaction_backend_data
{
2532 struct ref_transaction
*packed_transaction
;
2533 int packed_refs_locked
;
2537 * Unlock any references in `transaction` that are still locked, and
2538 * mark the transaction closed.
2540 static void files_transaction_cleanup(struct files_ref_store
*refs
,
2541 struct ref_transaction
*transaction
)
2544 struct files_transaction_backend_data
*backend_data
=
2545 transaction
->backend_data
;
2546 struct strbuf err
= STRBUF_INIT
;
2548 for (i
= 0; i
< transaction
->nr
; i
++) {
2549 struct ref_update
*update
= transaction
->updates
[i
];
2550 struct ref_lock
*lock
= update
->backend_data
;
2554 update
->backend_data
= NULL
;
2558 if (backend_data
->packed_transaction
&&
2559 ref_transaction_abort(backend_data
->packed_transaction
, &err
)) {
2560 error("error aborting transaction: %s", err
.buf
);
2561 strbuf_release(&err
);
2564 if (backend_data
->packed_refs_locked
)
2565 packed_refs_unlock(refs
->packed_ref_store
);
2569 transaction
->state
= REF_TRANSACTION_CLOSED
;
2572 static int files_transaction_prepare(struct ref_store
*ref_store
,
2573 struct ref_transaction
*transaction
,
2576 struct files_ref_store
*refs
=
2577 files_downcast(ref_store
, REF_STORE_WRITE
,
2578 "ref_transaction_prepare");
2581 struct string_list affected_refnames
= STRING_LIST_INIT_NODUP
;
2582 char *head_ref
= NULL
;
2584 struct files_transaction_backend_data
*backend_data
;
2585 struct ref_transaction
*packed_transaction
= NULL
;
2589 if (!transaction
->nr
)
2592 backend_data
= xcalloc(1, sizeof(*backend_data
));
2593 transaction
->backend_data
= backend_data
;
2596 * Fail if a refname appears more than once in the
2597 * transaction. (If we end up splitting up any updates using
2598 * split_symref_update() or split_head_update(), those
2599 * functions will check that the new updates don't have the
2600 * same refname as any existing ones.) Also fail if any of the
2601 * updates use REF_IS_PRUNING without REF_NO_DEREF.
2603 for (i
= 0; i
< transaction
->nr
; i
++) {
2604 struct ref_update
*update
= transaction
->updates
[i
];
2605 struct string_list_item
*item
=
2606 string_list_append(&affected_refnames
, update
->refname
);
2608 if ((update
->flags
& REF_IS_PRUNING
) &&
2609 !(update
->flags
& REF_NO_DEREF
))
2610 BUG("REF_IS_PRUNING set without REF_NO_DEREF");
2613 * We store a pointer to update in item->util, but at
2614 * the moment we never use the value of this field
2615 * except to check whether it is non-NULL.
2617 item
->util
= update
;
2619 string_list_sort(&affected_refnames
);
2620 if (ref_update_reject_duplicates(&affected_refnames
, err
)) {
2621 ret
= TRANSACTION_GENERIC_ERROR
;
2626 * Special hack: If a branch is updated directly and HEAD
2627 * points to it (may happen on the remote side of a push
2628 * for example) then logically the HEAD reflog should be
2631 * A generic solution would require reverse symref lookups,
2632 * but finding all symrefs pointing to a given branch would be
2633 * rather costly for this rare event (the direct update of a
2634 * branch) to be worth it. So let's cheat and check with HEAD
2635 * only, which should cover 99% of all usage scenarios (even
2636 * 100% of the default ones).
2638 * So if HEAD is a symbolic reference, then record the name of
2639 * the reference that it points to. If we see an update of
2640 * head_ref within the transaction, then split_head_update()
2641 * arranges for the reflog of HEAD to be updated, too.
2643 head_ref
= refs_resolve_refdup(ref_store
, "HEAD",
2644 RESOLVE_REF_NO_RECURSE
,
2647 if (head_ref
&& !(head_type
& REF_ISSYMREF
)) {
2648 FREE_AND_NULL(head_ref
);
2652 * Acquire all locks, verify old values if provided, check
2653 * that new values are valid, and write new values to the
2654 * lockfiles, ready to be activated. Only keep one lockfile
2655 * open at a time to avoid running out of file descriptors.
2656 * Note that lock_ref_for_update() might append more updates
2657 * to the transaction.
2659 for (i
= 0; i
< transaction
->nr
; i
++) {
2660 struct ref_update
*update
= transaction
->updates
[i
];
2662 ret
= lock_ref_for_update(refs
, update
, transaction
,
2663 head_ref
, &affected_refnames
, err
);
2667 if (update
->flags
& REF_DELETING
&&
2668 !(update
->flags
& REF_LOG_ONLY
) &&
2669 !(update
->flags
& REF_IS_PRUNING
)) {
2671 * This reference has to be deleted from
2672 * packed-refs if it exists there.
2674 if (!packed_transaction
) {
2675 packed_transaction
= ref_store_transaction_begin(
2676 refs
->packed_ref_store
, err
);
2677 if (!packed_transaction
) {
2678 ret
= TRANSACTION_GENERIC_ERROR
;
2682 backend_data
->packed_transaction
=
2686 ref_transaction_add_update(
2687 packed_transaction
, update
->refname
,
2688 REF_HAVE_NEW
| REF_NO_DEREF
,
2689 &update
->new_oid
, NULL
,
2694 if (packed_transaction
) {
2695 if (packed_refs_lock(refs
->packed_ref_store
, 0, err
)) {
2696 ret
= TRANSACTION_GENERIC_ERROR
;
2699 backend_data
->packed_refs_locked
= 1;
2701 if (is_packed_transaction_needed(refs
->packed_ref_store
,
2702 packed_transaction
)) {
2703 ret
= ref_transaction_prepare(packed_transaction
, err
);
2706 * We can skip rewriting the `packed-refs`
2707 * file. But we do need to leave it locked, so
2708 * that somebody else doesn't pack a reference
2709 * that we are trying to delete.
2711 if (ref_transaction_abort(packed_transaction
, err
)) {
2712 ret
= TRANSACTION_GENERIC_ERROR
;
2715 backend_data
->packed_transaction
= NULL
;
2721 string_list_clear(&affected_refnames
, 0);
2724 files_transaction_cleanup(refs
, transaction
);
2726 transaction
->state
= REF_TRANSACTION_PREPARED
;
2731 static int files_transaction_finish(struct ref_store
*ref_store
,
2732 struct ref_transaction
*transaction
,
2735 struct files_ref_store
*refs
=
2736 files_downcast(ref_store
, 0, "ref_transaction_finish");
2739 struct strbuf sb
= STRBUF_INIT
;
2740 struct files_transaction_backend_data
*backend_data
;
2741 struct ref_transaction
*packed_transaction
;
2746 if (!transaction
->nr
) {
2747 transaction
->state
= REF_TRANSACTION_CLOSED
;
2751 backend_data
= transaction
->backend_data
;
2752 packed_transaction
= backend_data
->packed_transaction
;
2754 /* Perform updates first so live commits remain referenced */
2755 for (i
= 0; i
< transaction
->nr
; i
++) {
2756 struct ref_update
*update
= transaction
->updates
[i
];
2757 struct ref_lock
*lock
= update
->backend_data
;
2759 if (update
->flags
& REF_NEEDS_COMMIT
||
2760 update
->flags
& REF_LOG_ONLY
) {
2761 if (files_log_ref_write(refs
,
2765 update
->msg
, update
->flags
,
2767 char *old_msg
= strbuf_detach(err
, NULL
);
2769 strbuf_addf(err
, "cannot update the ref '%s': %s",
2770 lock
->ref_name
, old_msg
);
2773 update
->backend_data
= NULL
;
2774 ret
= TRANSACTION_GENERIC_ERROR
;
2778 if (update
->flags
& REF_NEEDS_COMMIT
) {
2779 clear_loose_ref_cache(refs
);
2780 if (commit_ref(lock
)) {
2781 strbuf_addf(err
, "couldn't set '%s'", lock
->ref_name
);
2783 update
->backend_data
= NULL
;
2784 ret
= TRANSACTION_GENERIC_ERROR
;
2791 * Now that updates are safely completed, we can perform
2792 * deletes. First delete the reflogs of any references that
2793 * will be deleted, since (in the unexpected event of an
2794 * error) leaving a reference without a reflog is less bad
2795 * than leaving a reflog without a reference (the latter is a
2796 * mildly invalid repository state):
2798 for (i
= 0; i
< transaction
->nr
; i
++) {
2799 struct ref_update
*update
= transaction
->updates
[i
];
2800 if (update
->flags
& REF_DELETING
&&
2801 !(update
->flags
& REF_LOG_ONLY
) &&
2802 !(update
->flags
& REF_IS_PRUNING
)) {
2804 files_reflog_path(refs
, &sb
, update
->refname
);
2805 if (!unlink_or_warn(sb
.buf
))
2806 try_remove_empty_parents(refs
, update
->refname
,
2807 REMOVE_EMPTY_PARENTS_REFLOG
);
2812 * Perform deletes now that updates are safely completed.
2814 * First delete any packed versions of the references, while
2815 * retaining the packed-refs lock:
2817 if (packed_transaction
) {
2818 ret
= ref_transaction_commit(packed_transaction
, err
);
2819 ref_transaction_free(packed_transaction
);
2820 packed_transaction
= NULL
;
2821 backend_data
->packed_transaction
= NULL
;
2826 /* Now delete the loose versions of the references: */
2827 for (i
= 0; i
< transaction
->nr
; i
++) {
2828 struct ref_update
*update
= transaction
->updates
[i
];
2829 struct ref_lock
*lock
= update
->backend_data
;
2831 if (update
->flags
& REF_DELETING
&&
2832 !(update
->flags
& REF_LOG_ONLY
)) {
2833 if (!(update
->type
& REF_ISPACKED
) ||
2834 update
->type
& REF_ISSYMREF
) {
2835 /* It is a loose reference. */
2837 files_ref_path(refs
, &sb
, lock
->ref_name
);
2838 if (unlink_or_msg(sb
.buf
, err
)) {
2839 ret
= TRANSACTION_GENERIC_ERROR
;
2842 update
->flags
|= REF_DELETED_LOOSE
;
2847 clear_loose_ref_cache(refs
);
2850 files_transaction_cleanup(refs
, transaction
);
2852 for (i
= 0; i
< transaction
->nr
; i
++) {
2853 struct ref_update
*update
= transaction
->updates
[i
];
2855 if (update
->flags
& REF_DELETED_LOOSE
) {
2857 * The loose reference was deleted. Delete any
2858 * empty parent directories. (Note that this
2859 * can only work because we have already
2860 * removed the lockfile.)
2862 try_remove_empty_parents(refs
, update
->refname
,
2863 REMOVE_EMPTY_PARENTS_REF
);
2867 strbuf_release(&sb
);
2871 static int files_transaction_abort(struct ref_store
*ref_store
,
2872 struct ref_transaction
*transaction
,
2875 struct files_ref_store
*refs
=
2876 files_downcast(ref_store
, 0, "ref_transaction_abort");
2878 files_transaction_cleanup(refs
, transaction
);
2882 static int ref_present(const char *refname
,
2883 const struct object_id
*oid
, int flags
, void *cb_data
)
2885 struct string_list
*affected_refnames
= cb_data
;
2887 return string_list_has_string(affected_refnames
, refname
);
2890 static int files_initial_transaction_commit(struct ref_store
*ref_store
,
2891 struct ref_transaction
*transaction
,
2894 struct files_ref_store
*refs
=
2895 files_downcast(ref_store
, REF_STORE_WRITE
,
2896 "initial_ref_transaction_commit");
2899 struct string_list affected_refnames
= STRING_LIST_INIT_NODUP
;
2900 struct ref_transaction
*packed_transaction
= NULL
;
2904 if (transaction
->state
!= REF_TRANSACTION_OPEN
)
2905 BUG("commit called for transaction that is not open");
2907 /* Fail if a refname appears more than once in the transaction: */
2908 for (i
= 0; i
< transaction
->nr
; i
++)
2909 string_list_append(&affected_refnames
,
2910 transaction
->updates
[i
]->refname
);
2911 string_list_sort(&affected_refnames
);
2912 if (ref_update_reject_duplicates(&affected_refnames
, err
)) {
2913 ret
= TRANSACTION_GENERIC_ERROR
;
2918 * It's really undefined to call this function in an active
2919 * repository or when there are existing references: we are
2920 * only locking and changing packed-refs, so (1) any
2921 * simultaneous processes might try to change a reference at
2922 * the same time we do, and (2) any existing loose versions of
2923 * the references that we are setting would have precedence
2924 * over our values. But some remote helpers create the remote
2925 * "HEAD" and "master" branches before calling this function,
2926 * so here we really only check that none of the references
2927 * that we are creating already exists.
2929 if (refs_for_each_rawref(&refs
->base
, ref_present
,
2930 &affected_refnames
))
2931 BUG("initial ref transaction called with existing refs");
2933 packed_transaction
= ref_store_transaction_begin(refs
->packed_ref_store
, err
);
2934 if (!packed_transaction
) {
2935 ret
= TRANSACTION_GENERIC_ERROR
;
2939 for (i
= 0; i
< transaction
->nr
; i
++) {
2940 struct ref_update
*update
= transaction
->updates
[i
];
2942 if ((update
->flags
& REF_HAVE_OLD
) &&
2943 !is_null_oid(&update
->old_oid
))
2944 BUG("initial ref transaction with old_sha1 set");
2945 if (refs_verify_refname_available(&refs
->base
, update
->refname
,
2946 &affected_refnames
, NULL
,
2948 ret
= TRANSACTION_NAME_CONFLICT
;
2953 * Add a reference creation for this reference to the
2954 * packed-refs transaction:
2956 ref_transaction_add_update(packed_transaction
, update
->refname
,
2957 update
->flags
& ~REF_HAVE_OLD
,
2958 &update
->new_oid
, &update
->old_oid
,
2962 if (packed_refs_lock(refs
->packed_ref_store
, 0, err
)) {
2963 ret
= TRANSACTION_GENERIC_ERROR
;
2967 if (initial_ref_transaction_commit(packed_transaction
, err
)) {
2968 ret
= TRANSACTION_GENERIC_ERROR
;
2971 packed_refs_unlock(refs
->packed_ref_store
);
2973 if (packed_transaction
)
2974 ref_transaction_free(packed_transaction
);
2975 transaction
->state
= REF_TRANSACTION_CLOSED
;
2976 string_list_clear(&affected_refnames
, 0);
2980 struct expire_reflog_cb
{
2982 reflog_expiry_should_prune_fn
*should_prune_fn
;
2985 struct object_id last_kept_oid
;
2988 static int expire_reflog_ent(struct object_id
*ooid
, struct object_id
*noid
,
2989 const char *email
, timestamp_t timestamp
, int tz
,
2990 const char *message
, void *cb_data
)
2992 struct expire_reflog_cb
*cb
= cb_data
;
2993 struct expire_reflog_policy_cb
*policy_cb
= cb
->policy_cb
;
2995 if (cb
->flags
& EXPIRE_REFLOGS_REWRITE
)
2996 ooid
= &cb
->last_kept_oid
;
2998 if ((*cb
->should_prune_fn
)(ooid
, noid
, email
, timestamp
, tz
,
2999 message
, policy_cb
)) {
3001 printf("would prune %s", message
);
3002 else if (cb
->flags
& EXPIRE_REFLOGS_VERBOSE
)
3003 printf("prune %s", message
);
3006 fprintf(cb
->newlog
, "%s %s %s %"PRItime
" %+05d\t%s",
3007 oid_to_hex(ooid
), oid_to_hex(noid
),
3008 email
, timestamp
, tz
, message
);
3009 oidcpy(&cb
->last_kept_oid
, noid
);
3011 if (cb
->flags
& EXPIRE_REFLOGS_VERBOSE
)
3012 printf("keep %s", message
);
3017 static int files_reflog_expire(struct ref_store
*ref_store
,
3018 const char *refname
, const struct object_id
*oid
,
3020 reflog_expiry_prepare_fn prepare_fn
,
3021 reflog_expiry_should_prune_fn should_prune_fn
,
3022 reflog_expiry_cleanup_fn cleanup_fn
,
3023 void *policy_cb_data
)
3025 struct files_ref_store
*refs
=
3026 files_downcast(ref_store
, REF_STORE_WRITE
, "reflog_expire");
3027 struct lock_file reflog_lock
= LOCK_INIT
;
3028 struct expire_reflog_cb cb
;
3029 struct ref_lock
*lock
;
3030 struct strbuf log_file_sb
= STRBUF_INIT
;
3034 struct strbuf err
= STRBUF_INIT
;
3036 memset(&cb
, 0, sizeof(cb
));
3038 cb
.policy_cb
= policy_cb_data
;
3039 cb
.should_prune_fn
= should_prune_fn
;
3042 * The reflog file is locked by holding the lock on the
3043 * reference itself, plus we might need to update the
3044 * reference if --updateref was specified:
3046 lock
= lock_ref_oid_basic(refs
, refname
, oid
,
3047 NULL
, NULL
, REF_NO_DEREF
,
3050 error("cannot lock ref '%s': %s", refname
, err
.buf
);
3051 strbuf_release(&err
);
3054 if (!refs_reflog_exists(ref_store
, refname
)) {
3059 files_reflog_path(refs
, &log_file_sb
, refname
);
3060 log_file
= strbuf_detach(&log_file_sb
, NULL
);
3061 if (!(flags
& EXPIRE_REFLOGS_DRY_RUN
)) {
3063 * Even though holding $GIT_DIR/logs/$reflog.lock has
3064 * no locking implications, we use the lock_file
3065 * machinery here anyway because it does a lot of the
3066 * work we need, including cleaning up if the program
3067 * exits unexpectedly.
3069 if (hold_lock_file_for_update(&reflog_lock
, log_file
, 0) < 0) {
3070 struct strbuf err
= STRBUF_INIT
;
3071 unable_to_lock_message(log_file
, errno
, &err
);
3072 error("%s", err
.buf
);
3073 strbuf_release(&err
);
3076 cb
.newlog
= fdopen_lock_file(&reflog_lock
, "w");
3078 error("cannot fdopen %s (%s)",
3079 get_lock_file_path(&reflog_lock
), strerror(errno
));
3084 (*prepare_fn
)(refname
, oid
, cb
.policy_cb
);
3085 refs_for_each_reflog_ent(ref_store
, refname
, expire_reflog_ent
, &cb
);
3086 (*cleanup_fn
)(cb
.policy_cb
);
3088 if (!(flags
& EXPIRE_REFLOGS_DRY_RUN
)) {
3090 * It doesn't make sense to adjust a reference pointed
3091 * to by a symbolic ref based on expiring entries in
3092 * the symbolic reference's reflog. Nor can we update
3093 * a reference if there are no remaining reflog
3096 int update
= (flags
& EXPIRE_REFLOGS_UPDATE_REF
) &&
3097 !(type
& REF_ISSYMREF
) &&
3098 !is_null_oid(&cb
.last_kept_oid
);
3100 if (close_lock_file_gently(&reflog_lock
)) {
3101 status
|= error("couldn't write %s: %s", log_file
,
3103 rollback_lock_file(&reflog_lock
);
3104 } else if (update
&&
3105 (write_in_full(get_lock_file_fd(&lock
->lk
),
3106 oid_to_hex(&cb
.last_kept_oid
), the_hash_algo
->hexsz
) < 0 ||
3107 write_str_in_full(get_lock_file_fd(&lock
->lk
), "\n") < 0 ||
3108 close_ref_gently(lock
) < 0)) {
3109 status
|= error("couldn't write %s",
3110 get_lock_file_path(&lock
->lk
));
3111 rollback_lock_file(&reflog_lock
);
3112 } else if (commit_lock_file(&reflog_lock
)) {
3113 status
|= error("unable to write reflog '%s' (%s)",
3114 log_file
, strerror(errno
));
3115 } else if (update
&& commit_ref(lock
)) {
3116 status
|= error("couldn't set %s", lock
->ref_name
);
3124 rollback_lock_file(&reflog_lock
);
3130 static int files_init_db(struct ref_store
*ref_store
, struct strbuf
*err
)
3132 struct files_ref_store
*refs
=
3133 files_downcast(ref_store
, REF_STORE_WRITE
, "init_db");
3134 struct strbuf sb
= STRBUF_INIT
;
3137 * Create .git/refs/{heads,tags}
3139 files_ref_path(refs
, &sb
, "refs/heads");
3140 safe_create_dir(sb
.buf
, 1);
3143 files_ref_path(refs
, &sb
, "refs/tags");
3144 safe_create_dir(sb
.buf
, 1);
3146 strbuf_release(&sb
);
3150 struct ref_storage_be refs_be_files
= {
3153 files_ref_store_create
,
3155 files_transaction_prepare
,
3156 files_transaction_finish
,
3157 files_transaction_abort
,
3158 files_initial_transaction_commit
,
3161 files_create_symref
,
3166 files_ref_iterator_begin
,
3169 files_reflog_iterator_begin
,
3170 files_for_each_reflog_ent
,
3171 files_for_each_reflog_ent_reverse
,
3172 files_reflog_exists
,
3173 files_create_reflog
,
3174 files_delete_reflog
,