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 files_reflog_path_other_worktrees(refs
, sb
, refname
);
185 case REF_TYPE_NORMAL
:
186 strbuf_addf(sb
, "%s/logs/%s", refs
->gitcommondir
, refname
);
189 BUG("unknown ref type %d of ref %s",
190 ref_type(refname
), refname
);
194 static void files_ref_path(struct files_ref_store
*refs
,
198 switch (ref_type(refname
)) {
199 case REF_TYPE_PER_WORKTREE
:
200 case REF_TYPE_PSEUDOREF
:
201 strbuf_addf(sb
, "%s/%s", refs
->gitdir
, refname
);
203 case REF_TYPE_MAIN_PSEUDOREF
:
204 if (!skip_prefix(refname
, "main-worktree/", &refname
))
205 BUG("ref %s is not a main pseudoref", refname
);
207 case REF_TYPE_OTHER_PSEUDOREF
:
208 case REF_TYPE_NORMAL
:
209 strbuf_addf(sb
, "%s/%s", refs
->gitcommondir
, refname
);
212 BUG("unknown ref type %d of ref %s",
213 ref_type(refname
), refname
);
218 * Read the loose references from the namespace dirname into dir
219 * (without recursing). dirname must end with '/'. dir must be the
220 * directory entry corresponding to dirname.
222 static void loose_fill_ref_dir(struct ref_store
*ref_store
,
223 struct ref_dir
*dir
, const char *dirname
)
225 struct files_ref_store
*refs
=
226 files_downcast(ref_store
, REF_STORE_READ
, "fill_ref_dir");
229 int dirnamelen
= strlen(dirname
);
230 struct strbuf refname
;
231 struct strbuf path
= STRBUF_INIT
;
234 files_ref_path(refs
, &path
, dirname
);
235 path_baselen
= path
.len
;
237 d
= opendir(path
.buf
);
239 strbuf_release(&path
);
243 strbuf_init(&refname
, dirnamelen
+ 257);
244 strbuf_add(&refname
, dirname
, dirnamelen
);
246 while ((de
= readdir(d
)) != NULL
) {
247 struct object_id oid
;
251 if (de
->d_name
[0] == '.')
253 if (ends_with(de
->d_name
, ".lock"))
255 strbuf_addstr(&refname
, de
->d_name
);
256 strbuf_addstr(&path
, de
->d_name
);
257 if (stat(path
.buf
, &st
) < 0) {
258 ; /* silently ignore */
259 } else if (S_ISDIR(st
.st_mode
)) {
260 strbuf_addch(&refname
, '/');
261 add_entry_to_dir(dir
,
262 create_dir_entry(dir
->cache
, refname
.buf
,
265 if (!refs_resolve_ref_unsafe(&refs
->base
,
270 flag
|= REF_ISBROKEN
;
271 } else if (is_null_oid(&oid
)) {
273 * It is so astronomically unlikely
274 * that null_oid is the OID of an
275 * actual object that we consider its
276 * appearance in a loose reference
277 * file to be repo corruption
278 * (probably due to a software bug).
280 flag
|= REF_ISBROKEN
;
283 if (check_refname_format(refname
.buf
,
284 REFNAME_ALLOW_ONELEVEL
)) {
285 if (!refname_is_safe(refname
.buf
))
286 die("loose refname is dangerous: %s", refname
.buf
);
288 flag
|= REF_BAD_NAME
| REF_ISBROKEN
;
290 add_entry_to_dir(dir
,
291 create_ref_entry(refname
.buf
, &oid
, flag
));
293 strbuf_setlen(&refname
, dirnamelen
);
294 strbuf_setlen(&path
, path_baselen
);
296 strbuf_release(&refname
);
297 strbuf_release(&path
);
301 * Manually add refs/bisect and refs/worktree, which, being
302 * per-worktree, might not appear in the directory listing for
303 * refs/ in the main repo.
305 if (!strcmp(dirname
, "refs/")) {
306 int pos
= search_ref_dir(dir
, "refs/bisect/", 12);
309 struct ref_entry
*child_entry
= create_dir_entry(
310 dir
->cache
, "refs/bisect/", 12, 1);
311 add_entry_to_dir(dir
, child_entry
);
314 pos
= search_ref_dir(dir
, "refs/worktree/", 11);
317 struct ref_entry
*child_entry
= create_dir_entry(
318 dir
->cache
, "refs/worktree/", 11, 1);
319 add_entry_to_dir(dir
, child_entry
);
324 static struct ref_cache
*get_loose_ref_cache(struct files_ref_store
*refs
)
328 * Mark the top-level directory complete because we
329 * are about to read the only subdirectory that can
332 refs
->loose
= create_ref_cache(&refs
->base
, loose_fill_ref_dir
);
334 /* We're going to fill the top level ourselves: */
335 refs
->loose
->root
->flag
&= ~REF_INCOMPLETE
;
338 * Add an incomplete entry for "refs/" (to be filled
341 add_entry_to_dir(get_ref_dir(refs
->loose
->root
),
342 create_dir_entry(refs
->loose
, "refs/", 5, 1));
347 static int files_read_raw_ref(struct ref_store
*ref_store
,
348 const char *refname
, struct object_id
*oid
,
349 struct strbuf
*referent
, unsigned int *type
)
351 struct files_ref_store
*refs
=
352 files_downcast(ref_store
, REF_STORE_READ
, "read_raw_ref");
353 struct strbuf sb_contents
= STRBUF_INIT
;
354 struct strbuf sb_path
= STRBUF_INIT
;
362 int remaining_retries
= 3;
365 strbuf_reset(&sb_path
);
367 files_ref_path(refs
, &sb_path
, refname
);
373 * We might have to loop back here to avoid a race
374 * condition: first we lstat() the file, then we try
375 * to read it as a link or as a file. But if somebody
376 * changes the type of the file (file <-> directory
377 * <-> symlink) between the lstat() and reading, then
378 * we don't want to report that as an error but rather
379 * try again starting with the lstat().
381 * We'll keep a count of the retries, though, just to avoid
382 * any confusing situation sending us into an infinite loop.
385 if (remaining_retries
-- <= 0)
388 if (lstat(path
, &st
) < 0) {
391 if (refs_read_raw_ref(refs
->packed_ref_store
, refname
,
392 oid
, referent
, type
)) {
400 /* Follow "normalized" - ie "refs/.." symlinks by hand */
401 if (S_ISLNK(st
.st_mode
)) {
402 strbuf_reset(&sb_contents
);
403 if (strbuf_readlink(&sb_contents
, path
, st
.st_size
) < 0) {
404 if (errno
== ENOENT
|| errno
== EINVAL
)
405 /* inconsistent with lstat; retry */
410 if (starts_with(sb_contents
.buf
, "refs/") &&
411 !check_refname_format(sb_contents
.buf
, 0)) {
412 strbuf_swap(&sb_contents
, referent
);
413 *type
|= REF_ISSYMREF
;
418 * It doesn't look like a refname; fall through to just
419 * treating it like a non-symlink, and reading whatever it
424 /* Is it a directory? */
425 if (S_ISDIR(st
.st_mode
)) {
427 * Even though there is a directory where the loose
428 * ref is supposed to be, there could still be a
431 if (refs_read_raw_ref(refs
->packed_ref_store
, refname
,
432 oid
, referent
, type
)) {
441 * Anything else, just open it and try to use it as
444 fd
= open(path
, O_RDONLY
);
446 if (errno
== ENOENT
&& !S_ISLNK(st
.st_mode
))
447 /* inconsistent with lstat; retry */
452 strbuf_reset(&sb_contents
);
453 if (strbuf_read(&sb_contents
, fd
, 256) < 0) {
454 int save_errno
= errno
;
460 strbuf_rtrim(&sb_contents
);
461 buf
= sb_contents
.buf
;
462 if (starts_with(buf
, "ref:")) {
464 while (isspace(*buf
))
467 strbuf_reset(referent
);
468 strbuf_addstr(referent
, buf
);
469 *type
|= REF_ISSYMREF
;
475 * Please note that FETCH_HEAD has additional
476 * data after the sha.
478 if (parse_oid_hex(buf
, oid
, &p
) ||
479 (*p
!= '\0' && !isspace(*p
))) {
480 *type
|= REF_ISBROKEN
;
489 strbuf_release(&sb_path
);
490 strbuf_release(&sb_contents
);
495 static void unlock_ref(struct ref_lock
*lock
)
497 rollback_lock_file(&lock
->lk
);
498 free(lock
->ref_name
);
503 * Lock refname, without following symrefs, and set *lock_p to point
504 * at a newly-allocated lock object. Fill in lock->old_oid, referent,
505 * and type similarly to read_raw_ref().
507 * The caller must verify that refname is a "safe" reference name (in
508 * the sense of refname_is_safe()) before calling this function.
510 * If the reference doesn't already exist, verify that refname doesn't
511 * have a D/F conflict with any existing references. extras and skip
512 * are passed to refs_verify_refname_available() for this check.
514 * If mustexist is not set and the reference is not found or is
515 * broken, lock the reference anyway but clear old_oid.
517 * Return 0 on success. On failure, write an error message to err and
518 * return TRANSACTION_NAME_CONFLICT or TRANSACTION_GENERIC_ERROR.
520 * Implementation note: This function is basically
525 * but it includes a lot more code to
526 * - Deal with possible races with other processes
527 * - Avoid calling refs_verify_refname_available() when it can be
528 * avoided, namely if we were successfully able to read the ref
529 * - Generate informative error messages in the case of failure
531 static int lock_raw_ref(struct files_ref_store
*refs
,
532 const char *refname
, int mustexist
,
533 const struct string_list
*extras
,
534 const struct string_list
*skip
,
535 struct ref_lock
**lock_p
,
536 struct strbuf
*referent
,
540 struct ref_lock
*lock
;
541 struct strbuf ref_file
= STRBUF_INIT
;
542 int attempts_remaining
= 3;
543 int ret
= TRANSACTION_GENERIC_ERROR
;
546 files_assert_main_repository(refs
, "lock_raw_ref");
550 /* First lock the file so it can't change out from under us. */
552 *lock_p
= lock
= xcalloc(1, sizeof(*lock
));
554 lock
->ref_name
= xstrdup(refname
);
555 files_ref_path(refs
, &ref_file
, refname
);
558 switch (safe_create_leading_directories(ref_file
.buf
)) {
563 * Suppose refname is "refs/foo/bar". We just failed
564 * to create the containing directory, "refs/foo",
565 * because there was a non-directory in the way. This
566 * indicates a D/F conflict, probably because of
567 * another reference such as "refs/foo". There is no
568 * reason to expect this error to be transitory.
570 if (refs_verify_refname_available(&refs
->base
, refname
,
571 extras
, skip
, err
)) {
574 * To the user the relevant error is
575 * that the "mustexist" reference is
579 strbuf_addf(err
, "unable to resolve reference '%s'",
583 * The error message set by
584 * refs_verify_refname_available() is
587 ret
= TRANSACTION_NAME_CONFLICT
;
591 * The file that is in the way isn't a loose
592 * reference. Report it as a low-level
595 strbuf_addf(err
, "unable to create lock file %s.lock; "
596 "non-directory in the way",
601 /* Maybe another process was tidying up. Try again. */
602 if (--attempts_remaining
> 0)
606 strbuf_addf(err
, "unable to create directory for %s",
611 if (hold_lock_file_for_update_timeout(
612 &lock
->lk
, ref_file
.buf
, LOCK_NO_DEREF
,
613 get_files_ref_lock_timeout_ms()) < 0) {
614 if (errno
== ENOENT
&& --attempts_remaining
> 0) {
616 * Maybe somebody just deleted one of the
617 * directories leading to ref_file. Try
622 unable_to_lock_message(ref_file
.buf
, errno
, err
);
628 * Now we hold the lock and can read the reference without
629 * fear that its value will change.
632 if (files_read_raw_ref(&refs
->base
, refname
,
633 &lock
->old_oid
, referent
, type
)) {
634 if (errno
== ENOENT
) {
636 /* Garden variety missing reference. */
637 strbuf_addf(err
, "unable to resolve reference '%s'",
642 * Reference is missing, but that's OK. We
643 * know that there is not a conflict with
644 * another loose reference because
645 * (supposing that we are trying to lock
646 * reference "refs/foo/bar"):
648 * - We were successfully able to create
649 * the lockfile refs/foo/bar.lock, so we
650 * know there cannot be a loose reference
653 * - We got ENOENT and not EISDIR, so we
654 * know that there cannot be a loose
655 * reference named "refs/foo/bar/baz".
658 } else if (errno
== EISDIR
) {
660 * There is a directory in the way. It might have
661 * contained references that have been deleted. If
662 * we don't require that the reference already
663 * exists, try to remove the directory so that it
664 * doesn't cause trouble when we want to rename the
665 * lockfile into place later.
668 /* Garden variety missing reference. */
669 strbuf_addf(err
, "unable to resolve reference '%s'",
672 } else if (remove_dir_recursively(&ref_file
,
673 REMOVE_DIR_EMPTY_ONLY
)) {
674 if (refs_verify_refname_available(
675 &refs
->base
, refname
,
676 extras
, skip
, err
)) {
678 * The error message set by
679 * verify_refname_available() is OK.
681 ret
= TRANSACTION_NAME_CONFLICT
;
685 * We can't delete the directory,
686 * but we also don't know of any
687 * references that it should
690 strbuf_addf(err
, "there is a non-empty directory '%s' "
691 "blocking reference '%s'",
692 ref_file
.buf
, refname
);
696 } else if (errno
== EINVAL
&& (*type
& REF_ISBROKEN
)) {
697 strbuf_addf(err
, "unable to resolve reference '%s': "
698 "reference broken", refname
);
701 strbuf_addf(err
, "unable to resolve reference '%s': %s",
702 refname
, strerror(errno
));
707 * If the ref did not exist and we are creating it,
708 * make sure there is no existing packed ref that
709 * conflicts with refname:
711 if (refs_verify_refname_available(
712 refs
->packed_ref_store
, refname
,
725 strbuf_release(&ref_file
);
729 struct files_ref_iterator
{
730 struct ref_iterator base
;
732 struct ref_iterator
*iter0
;
736 static int files_ref_iterator_advance(struct ref_iterator
*ref_iterator
)
738 struct files_ref_iterator
*iter
=
739 (struct files_ref_iterator
*)ref_iterator
;
742 while ((ok
= ref_iterator_advance(iter
->iter0
)) == ITER_OK
) {
743 if (iter
->flags
& DO_FOR_EACH_PER_WORKTREE_ONLY
&&
744 ref_type(iter
->iter0
->refname
) != REF_TYPE_PER_WORKTREE
)
747 if (!(iter
->flags
& DO_FOR_EACH_INCLUDE_BROKEN
) &&
748 !ref_resolves_to_object(iter
->iter0
->refname
,
753 iter
->base
.refname
= iter
->iter0
->refname
;
754 iter
->base
.oid
= iter
->iter0
->oid
;
755 iter
->base
.flags
= iter
->iter0
->flags
;
760 if (ref_iterator_abort(ref_iterator
) != ITER_DONE
)
766 static int files_ref_iterator_peel(struct ref_iterator
*ref_iterator
,
767 struct object_id
*peeled
)
769 struct files_ref_iterator
*iter
=
770 (struct files_ref_iterator
*)ref_iterator
;
772 return ref_iterator_peel(iter
->iter0
, peeled
);
775 static int files_ref_iterator_abort(struct ref_iterator
*ref_iterator
)
777 struct files_ref_iterator
*iter
=
778 (struct files_ref_iterator
*)ref_iterator
;
782 ok
= ref_iterator_abort(iter
->iter0
);
784 base_ref_iterator_free(ref_iterator
);
788 static struct ref_iterator_vtable files_ref_iterator_vtable
= {
789 files_ref_iterator_advance
,
790 files_ref_iterator_peel
,
791 files_ref_iterator_abort
794 static struct ref_iterator
*files_ref_iterator_begin(
795 struct ref_store
*ref_store
,
796 const char *prefix
, unsigned int flags
)
798 struct files_ref_store
*refs
;
799 struct ref_iterator
*loose_iter
, *packed_iter
, *overlay_iter
;
800 struct files_ref_iterator
*iter
;
801 struct ref_iterator
*ref_iterator
;
802 unsigned int required_flags
= REF_STORE_READ
;
804 if (!(flags
& DO_FOR_EACH_INCLUDE_BROKEN
))
805 required_flags
|= REF_STORE_ODB
;
807 refs
= files_downcast(ref_store
, required_flags
, "ref_iterator_begin");
810 * We must make sure that all loose refs are read before
811 * accessing the packed-refs file; this avoids a race
812 * condition if loose refs are migrated to the packed-refs
813 * file by a simultaneous process, but our in-memory view is
814 * from before the migration. We ensure this as follows:
815 * First, we call start the loose refs iteration with its
816 * `prime_ref` argument set to true. This causes the loose
817 * references in the subtree to be pre-read into the cache.
818 * (If they've already been read, that's OK; we only need to
819 * guarantee that they're read before the packed refs, not
820 * *how much* before.) After that, we call
821 * packed_ref_iterator_begin(), which internally checks
822 * whether the packed-ref cache is up to date with what is on
823 * disk, and re-reads it if not.
826 loose_iter
= cache_ref_iterator_begin(get_loose_ref_cache(refs
),
830 * The packed-refs file might contain broken references, for
831 * example an old version of a reference that points at an
832 * object that has since been garbage-collected. This is OK as
833 * long as there is a corresponding loose reference that
834 * overrides it, and we don't want to emit an error message in
835 * this case. So ask the packed_ref_store for all of its
836 * references, and (if needed) do our own check for broken
837 * ones in files_ref_iterator_advance(), after we have merged
838 * the packed and loose references.
840 packed_iter
= refs_ref_iterator_begin(
841 refs
->packed_ref_store
, prefix
, 0,
842 DO_FOR_EACH_INCLUDE_BROKEN
);
844 overlay_iter
= overlay_ref_iterator_begin(loose_iter
, packed_iter
);
846 iter
= xcalloc(1, sizeof(*iter
));
847 ref_iterator
= &iter
->base
;
848 base_ref_iterator_init(ref_iterator
, &files_ref_iterator_vtable
,
849 overlay_iter
->ordered
);
850 iter
->iter0
= overlay_iter
;
857 * Verify that the reference locked by lock has the value old_oid
858 * (unless it is NULL). Fail if the reference doesn't exist and
859 * mustexist is set. Return 0 on success. On error, write an error
860 * message to err, set errno, and return a negative value.
862 static int verify_lock(struct ref_store
*ref_store
, struct ref_lock
*lock
,
863 const struct object_id
*old_oid
, int mustexist
,
868 if (refs_read_ref_full(ref_store
, lock
->ref_name
,
869 mustexist
? RESOLVE_REF_READING
: 0,
870 &lock
->old_oid
, NULL
)) {
872 int save_errno
= errno
;
873 strbuf_addf(err
, "can't verify ref '%s'", lock
->ref_name
);
877 oidclr(&lock
->old_oid
);
881 if (old_oid
&& !oideq(&lock
->old_oid
, old_oid
)) {
882 strbuf_addf(err
, "ref '%s' is at %s but expected %s",
884 oid_to_hex(&lock
->old_oid
),
885 oid_to_hex(old_oid
));
892 static int remove_empty_directories(struct strbuf
*path
)
895 * we want to create a file but there is a directory there;
896 * if that is an empty directory (or a directory that contains
897 * only empty directories), remove them.
899 return remove_dir_recursively(path
, REMOVE_DIR_EMPTY_ONLY
);
902 static int create_reflock(const char *path
, void *cb
)
904 struct lock_file
*lk
= cb
;
906 return hold_lock_file_for_update_timeout(
907 lk
, path
, LOCK_NO_DEREF
,
908 get_files_ref_lock_timeout_ms()) < 0 ? -1 : 0;
912 * Locks a ref returning the lock on success and NULL on failure.
913 * On failure errno is set to something meaningful.
915 static struct ref_lock
*lock_ref_oid_basic(struct files_ref_store
*refs
,
917 const struct object_id
*old_oid
,
918 const struct string_list
*extras
,
919 const struct string_list
*skip
,
920 unsigned int flags
, int *type
,
923 struct strbuf ref_file
= STRBUF_INIT
;
924 struct ref_lock
*lock
;
926 int mustexist
= (old_oid
&& !is_null_oid(old_oid
));
927 int resolve_flags
= RESOLVE_REF_NO_RECURSE
;
930 files_assert_main_repository(refs
, "lock_ref_oid_basic");
933 lock
= xcalloc(1, sizeof(struct ref_lock
));
936 resolve_flags
|= RESOLVE_REF_READING
;
937 if (flags
& REF_DELETING
)
938 resolve_flags
|= RESOLVE_REF_ALLOW_BAD_NAME
;
940 files_ref_path(refs
, &ref_file
, refname
);
941 resolved
= !!refs_resolve_ref_unsafe(&refs
->base
,
942 refname
, resolve_flags
,
943 &lock
->old_oid
, type
);
944 if (!resolved
&& errno
== EISDIR
) {
946 * we are trying to lock foo but we used to
947 * have foo/bar which now does not exist;
948 * it is normal for the empty directory 'foo'
951 if (remove_empty_directories(&ref_file
)) {
953 if (!refs_verify_refname_available(
955 refname
, extras
, skip
, err
))
956 strbuf_addf(err
, "there are still refs under '%s'",
960 resolved
= !!refs_resolve_ref_unsafe(&refs
->base
,
961 refname
, resolve_flags
,
962 &lock
->old_oid
, type
);
966 if (last_errno
!= ENOTDIR
||
967 !refs_verify_refname_available(&refs
->base
, refname
,
969 strbuf_addf(err
, "unable to resolve reference '%s': %s",
970 refname
, strerror(last_errno
));
976 * If the ref did not exist and we are creating it, make sure
977 * there is no existing packed ref whose name begins with our
978 * refname, nor a packed ref whose name is a proper prefix of
981 if (is_null_oid(&lock
->old_oid
) &&
982 refs_verify_refname_available(refs
->packed_ref_store
, refname
,
983 extras
, skip
, err
)) {
984 last_errno
= ENOTDIR
;
988 lock
->ref_name
= xstrdup(refname
);
990 if (raceproof_create_file(ref_file
.buf
, create_reflock
, &lock
->lk
)) {
992 unable_to_lock_message(ref_file
.buf
, errno
, err
);
996 if (verify_lock(&refs
->base
, lock
, old_oid
, mustexist
, err
)) {
1007 strbuf_release(&ref_file
);
1012 struct ref_to_prune
{
1013 struct ref_to_prune
*next
;
1014 struct object_id oid
;
1015 char name
[FLEX_ARRAY
];
1019 REMOVE_EMPTY_PARENTS_REF
= 0x01,
1020 REMOVE_EMPTY_PARENTS_REFLOG
= 0x02
1024 * Remove empty parent directories associated with the specified
1025 * reference and/or its reflog, but spare [logs/]refs/ and immediate
1026 * subdirs. flags is a combination of REMOVE_EMPTY_PARENTS_REF and/or
1027 * REMOVE_EMPTY_PARENTS_REFLOG.
1029 static void try_remove_empty_parents(struct files_ref_store
*refs
,
1030 const char *refname
,
1033 struct strbuf buf
= STRBUF_INIT
;
1034 struct strbuf sb
= STRBUF_INIT
;
1038 strbuf_addstr(&buf
, refname
);
1040 for (i
= 0; i
< 2; i
++) { /* refs/{heads,tags,...}/ */
1041 while (*p
&& *p
!= '/')
1043 /* tolerate duplicate slashes; see check_refname_format() */
1047 q
= buf
.buf
+ buf
.len
;
1048 while (flags
& (REMOVE_EMPTY_PARENTS_REF
| REMOVE_EMPTY_PARENTS_REFLOG
)) {
1049 while (q
> p
&& *q
!= '/')
1051 while (q
> p
&& *(q
-1) == '/')
1055 strbuf_setlen(&buf
, q
- buf
.buf
);
1058 files_ref_path(refs
, &sb
, buf
.buf
);
1059 if ((flags
& REMOVE_EMPTY_PARENTS_REF
) && rmdir(sb
.buf
))
1060 flags
&= ~REMOVE_EMPTY_PARENTS_REF
;
1063 files_reflog_path(refs
, &sb
, buf
.buf
);
1064 if ((flags
& REMOVE_EMPTY_PARENTS_REFLOG
) && rmdir(sb
.buf
))
1065 flags
&= ~REMOVE_EMPTY_PARENTS_REFLOG
;
1067 strbuf_release(&buf
);
1068 strbuf_release(&sb
);
1071 /* make sure nobody touched the ref, and unlink */
1072 static void prune_ref(struct files_ref_store
*refs
, struct ref_to_prune
*r
)
1074 struct ref_transaction
*transaction
;
1075 struct strbuf err
= STRBUF_INIT
;
1078 if (check_refname_format(r
->name
, 0))
1081 transaction
= ref_store_transaction_begin(&refs
->base
, &err
);
1084 ref_transaction_add_update(
1085 transaction
, r
->name
,
1086 REF_NO_DEREF
| REF_HAVE_NEW
| REF_HAVE_OLD
| REF_IS_PRUNING
,
1087 &null_oid
, &r
->oid
, NULL
);
1088 if (ref_transaction_commit(transaction
, &err
))
1095 error("%s", err
.buf
);
1096 strbuf_release(&err
);
1097 ref_transaction_free(transaction
);
1102 * Prune the loose versions of the references in the linked list
1103 * `*refs_to_prune`, freeing the entries in the list as we go.
1105 static void prune_refs(struct files_ref_store
*refs
, struct ref_to_prune
**refs_to_prune
)
1107 while (*refs_to_prune
) {
1108 struct ref_to_prune
*r
= *refs_to_prune
;
1109 *refs_to_prune
= r
->next
;
1116 * Return true if the specified reference should be packed.
1118 static int should_pack_ref(const char *refname
,
1119 const struct object_id
*oid
, unsigned int ref_flags
,
1120 unsigned int pack_flags
)
1122 /* Do not pack per-worktree refs: */
1123 if (ref_type(refname
) != REF_TYPE_NORMAL
)
1126 /* Do not pack non-tags unless PACK_REFS_ALL is set: */
1127 if (!(pack_flags
& PACK_REFS_ALL
) && !starts_with(refname
, "refs/tags/"))
1130 /* Do not pack symbolic refs: */
1131 if (ref_flags
& REF_ISSYMREF
)
1134 /* Do not pack broken refs: */
1135 if (!ref_resolves_to_object(refname
, oid
, ref_flags
))
1141 static int files_pack_refs(struct ref_store
*ref_store
, unsigned int flags
)
1143 struct files_ref_store
*refs
=
1144 files_downcast(ref_store
, REF_STORE_WRITE
| REF_STORE_ODB
,
1146 struct ref_iterator
*iter
;
1148 struct ref_to_prune
*refs_to_prune
= NULL
;
1149 struct strbuf err
= STRBUF_INIT
;
1150 struct ref_transaction
*transaction
;
1152 transaction
= ref_store_transaction_begin(refs
->packed_ref_store
, &err
);
1156 packed_refs_lock(refs
->packed_ref_store
, LOCK_DIE_ON_ERROR
, &err
);
1158 iter
= cache_ref_iterator_begin(get_loose_ref_cache(refs
), NULL
, 0);
1159 while ((ok
= ref_iterator_advance(iter
)) == ITER_OK
) {
1161 * If the loose reference can be packed, add an entry
1162 * in the packed ref cache. If the reference should be
1163 * pruned, also add it to refs_to_prune.
1165 if (!should_pack_ref(iter
->refname
, iter
->oid
, iter
->flags
,
1170 * Add a reference creation for this reference to the
1171 * packed-refs transaction:
1173 if (ref_transaction_update(transaction
, iter
->refname
,
1175 REF_NO_DEREF
, NULL
, &err
))
1176 die("failure preparing to create packed reference %s: %s",
1177 iter
->refname
, err
.buf
);
1179 /* Schedule the loose reference for pruning if requested. */
1180 if ((flags
& PACK_REFS_PRUNE
)) {
1181 struct ref_to_prune
*n
;
1182 FLEX_ALLOC_STR(n
, name
, iter
->refname
);
1183 oidcpy(&n
->oid
, iter
->oid
);
1184 n
->next
= refs_to_prune
;
1188 if (ok
!= ITER_DONE
)
1189 die("error while iterating over references");
1191 if (ref_transaction_commit(transaction
, &err
))
1192 die("unable to write new packed-refs: %s", err
.buf
);
1194 ref_transaction_free(transaction
);
1196 packed_refs_unlock(refs
->packed_ref_store
);
1198 prune_refs(refs
, &refs_to_prune
);
1199 strbuf_release(&err
);
1203 static int files_delete_refs(struct ref_store
*ref_store
, const char *msg
,
1204 struct string_list
*refnames
, unsigned int flags
)
1206 struct files_ref_store
*refs
=
1207 files_downcast(ref_store
, REF_STORE_WRITE
, "delete_refs");
1208 struct strbuf err
= STRBUF_INIT
;
1214 if (packed_refs_lock(refs
->packed_ref_store
, 0, &err
))
1217 if (refs_delete_refs(refs
->packed_ref_store
, msg
, refnames
, flags
)) {
1218 packed_refs_unlock(refs
->packed_ref_store
);
1222 packed_refs_unlock(refs
->packed_ref_store
);
1224 for (i
= 0; i
< refnames
->nr
; i
++) {
1225 const char *refname
= refnames
->items
[i
].string
;
1227 if (refs_delete_ref(&refs
->base
, msg
, refname
, NULL
, flags
))
1228 result
|= error(_("could not remove reference %s"), refname
);
1231 strbuf_release(&err
);
1236 * If we failed to rewrite the packed-refs file, then it is
1237 * unsafe to try to remove loose refs, because doing so might
1238 * expose an obsolete packed value for a reference that might
1239 * even point at an object that has been garbage collected.
1241 if (refnames
->nr
== 1)
1242 error(_("could not delete reference %s: %s"),
1243 refnames
->items
[0].string
, err
.buf
);
1245 error(_("could not delete references: %s"), err
.buf
);
1247 strbuf_release(&err
);
1252 * People using contrib's git-new-workdir have .git/logs/refs ->
1253 * /some/other/path/.git/logs/refs, and that may live on another device.
1255 * IOW, to avoid cross device rename errors, the temporary renamed log must
1256 * live into logs/refs.
1258 #define TMP_RENAMED_LOG "refs/.tmp-renamed-log"
1261 const char *tmp_renamed_log
;
1265 static int rename_tmp_log_callback(const char *path
, void *cb_data
)
1267 struct rename_cb
*cb
= cb_data
;
1269 if (rename(cb
->tmp_renamed_log
, path
)) {
1271 * rename(a, b) when b is an existing directory ought
1272 * to result in ISDIR, but Solaris 5.8 gives ENOTDIR.
1273 * Sheesh. Record the true errno for error reporting,
1274 * but report EISDIR to raceproof_create_file() so
1275 * that it knows to retry.
1277 cb
->true_errno
= errno
;
1278 if (errno
== ENOTDIR
)
1286 static int rename_tmp_log(struct files_ref_store
*refs
, const char *newrefname
)
1288 struct strbuf path
= STRBUF_INIT
;
1289 struct strbuf tmp
= STRBUF_INIT
;
1290 struct rename_cb cb
;
1293 files_reflog_path(refs
, &path
, newrefname
);
1294 files_reflog_path(refs
, &tmp
, TMP_RENAMED_LOG
);
1295 cb
.tmp_renamed_log
= tmp
.buf
;
1296 ret
= raceproof_create_file(path
.buf
, rename_tmp_log_callback
, &cb
);
1298 if (errno
== EISDIR
)
1299 error("directory not empty: %s", path
.buf
);
1301 error("unable to move logfile %s to %s: %s",
1303 strerror(cb
.true_errno
));
1306 strbuf_release(&path
);
1307 strbuf_release(&tmp
);
1311 static int write_ref_to_lockfile(struct ref_lock
*lock
,
1312 const struct object_id
*oid
, struct strbuf
*err
);
1313 static int commit_ref_update(struct files_ref_store
*refs
,
1314 struct ref_lock
*lock
,
1315 const struct object_id
*oid
, const char *logmsg
,
1316 struct strbuf
*err
);
1318 static int files_copy_or_rename_ref(struct ref_store
*ref_store
,
1319 const char *oldrefname
, const char *newrefname
,
1320 const char *logmsg
, int copy
)
1322 struct files_ref_store
*refs
=
1323 files_downcast(ref_store
, REF_STORE_WRITE
, "rename_ref");
1324 struct object_id oid
, orig_oid
;
1325 int flag
= 0, logmoved
= 0;
1326 struct ref_lock
*lock
;
1327 struct stat loginfo
;
1328 struct strbuf sb_oldref
= STRBUF_INIT
;
1329 struct strbuf sb_newref
= STRBUF_INIT
;
1330 struct strbuf tmp_renamed_log
= STRBUF_INIT
;
1332 struct strbuf err
= STRBUF_INIT
;
1334 files_reflog_path(refs
, &sb_oldref
, oldrefname
);
1335 files_reflog_path(refs
, &sb_newref
, newrefname
);
1336 files_reflog_path(refs
, &tmp_renamed_log
, TMP_RENAMED_LOG
);
1338 log
= !lstat(sb_oldref
.buf
, &loginfo
);
1339 if (log
&& S_ISLNK(loginfo
.st_mode
)) {
1340 ret
= error("reflog for %s is a symlink", oldrefname
);
1344 if (!refs_resolve_ref_unsafe(&refs
->base
, oldrefname
,
1345 RESOLVE_REF_READING
| RESOLVE_REF_NO_RECURSE
,
1346 &orig_oid
, &flag
)) {
1347 ret
= error("refname %s not found", oldrefname
);
1351 if (flag
& REF_ISSYMREF
) {
1353 ret
= error("refname %s is a symbolic ref, copying it is not supported",
1356 ret
= error("refname %s is a symbolic ref, renaming it is not supported",
1360 if (!refs_rename_ref_available(&refs
->base
, oldrefname
, newrefname
)) {
1365 if (!copy
&& log
&& rename(sb_oldref
.buf
, tmp_renamed_log
.buf
)) {
1366 ret
= error("unable to move logfile logs/%s to logs/"TMP_RENAMED_LOG
": %s",
1367 oldrefname
, strerror(errno
));
1371 if (copy
&& log
&& copy_file(tmp_renamed_log
.buf
, sb_oldref
.buf
, 0644)) {
1372 ret
= error("unable to copy logfile logs/%s to logs/"TMP_RENAMED_LOG
": %s",
1373 oldrefname
, strerror(errno
));
1377 if (!copy
&& refs_delete_ref(&refs
->base
, logmsg
, oldrefname
,
1378 &orig_oid
, REF_NO_DEREF
)) {
1379 error("unable to delete old %s", oldrefname
);
1384 * Since we are doing a shallow lookup, oid is not the
1385 * correct value to pass to delete_ref as old_oid. But that
1386 * doesn't matter, because an old_oid check wouldn't add to
1387 * the safety anyway; we want to delete the reference whatever
1388 * its current value.
1390 if (!copy
&& !refs_read_ref_full(&refs
->base
, newrefname
,
1391 RESOLVE_REF_READING
| RESOLVE_REF_NO_RECURSE
,
1393 refs_delete_ref(&refs
->base
, NULL
, newrefname
,
1394 NULL
, REF_NO_DEREF
)) {
1395 if (errno
== EISDIR
) {
1396 struct strbuf path
= STRBUF_INIT
;
1399 files_ref_path(refs
, &path
, newrefname
);
1400 result
= remove_empty_directories(&path
);
1401 strbuf_release(&path
);
1404 error("Directory not empty: %s", newrefname
);
1408 error("unable to delete existing %s", newrefname
);
1413 if (log
&& rename_tmp_log(refs
, newrefname
))
1418 lock
= lock_ref_oid_basic(refs
, newrefname
, NULL
, NULL
, NULL
,
1419 REF_NO_DEREF
, NULL
, &err
);
1422 error("unable to copy '%s' to '%s': %s", oldrefname
, newrefname
, err
.buf
);
1424 error("unable to rename '%s' to '%s': %s", oldrefname
, newrefname
, err
.buf
);
1425 strbuf_release(&err
);
1428 oidcpy(&lock
->old_oid
, &orig_oid
);
1430 if (write_ref_to_lockfile(lock
, &orig_oid
, &err
) ||
1431 commit_ref_update(refs
, lock
, &orig_oid
, logmsg
, &err
)) {
1432 error("unable to write current sha1 into %s: %s", newrefname
, err
.buf
);
1433 strbuf_release(&err
);
1441 lock
= lock_ref_oid_basic(refs
, oldrefname
, NULL
, NULL
, NULL
,
1442 REF_NO_DEREF
, NULL
, &err
);
1444 error("unable to lock %s for rollback: %s", oldrefname
, err
.buf
);
1445 strbuf_release(&err
);
1449 flag
= log_all_ref_updates
;
1450 log_all_ref_updates
= LOG_REFS_NONE
;
1451 if (write_ref_to_lockfile(lock
, &orig_oid
, &err
) ||
1452 commit_ref_update(refs
, lock
, &orig_oid
, NULL
, &err
)) {
1453 error("unable to write current sha1 into %s: %s", oldrefname
, err
.buf
);
1454 strbuf_release(&err
);
1456 log_all_ref_updates
= flag
;
1459 if (logmoved
&& rename(sb_newref
.buf
, sb_oldref
.buf
))
1460 error("unable to restore logfile %s from %s: %s",
1461 oldrefname
, newrefname
, strerror(errno
));
1462 if (!logmoved
&& log
&&
1463 rename(tmp_renamed_log
.buf
, sb_oldref
.buf
))
1464 error("unable to restore logfile %s from logs/"TMP_RENAMED_LOG
": %s",
1465 oldrefname
, strerror(errno
));
1468 strbuf_release(&sb_newref
);
1469 strbuf_release(&sb_oldref
);
1470 strbuf_release(&tmp_renamed_log
);
1475 static int files_rename_ref(struct ref_store
*ref_store
,
1476 const char *oldrefname
, const char *newrefname
,
1479 return files_copy_or_rename_ref(ref_store
, oldrefname
,
1480 newrefname
, logmsg
, 0);
1483 static int files_copy_ref(struct ref_store
*ref_store
,
1484 const char *oldrefname
, const char *newrefname
,
1487 return files_copy_or_rename_ref(ref_store
, oldrefname
,
1488 newrefname
, logmsg
, 1);
1491 static int close_ref_gently(struct ref_lock
*lock
)
1493 if (close_lock_file_gently(&lock
->lk
))
1498 static int commit_ref(struct ref_lock
*lock
)
1500 char *path
= get_locked_file_path(&lock
->lk
);
1503 if (!lstat(path
, &st
) && S_ISDIR(st
.st_mode
)) {
1505 * There is a directory at the path we want to rename
1506 * the lockfile to. Hopefully it is empty; try to
1509 size_t len
= strlen(path
);
1510 struct strbuf sb_path
= STRBUF_INIT
;
1512 strbuf_attach(&sb_path
, path
, len
, len
);
1515 * If this fails, commit_lock_file() will also fail
1516 * and will report the problem.
1518 remove_empty_directories(&sb_path
);
1519 strbuf_release(&sb_path
);
1524 if (commit_lock_file(&lock
->lk
))
1529 static int open_or_create_logfile(const char *path
, void *cb
)
1533 *fd
= open(path
, O_APPEND
| O_WRONLY
| O_CREAT
, 0666);
1534 return (*fd
< 0) ? -1 : 0;
1538 * Create a reflog for a ref. If force_create = 0, only create the
1539 * reflog for certain refs (those for which should_autocreate_reflog
1540 * returns non-zero). Otherwise, create it regardless of the reference
1541 * name. If the logfile already existed or was created, return 0 and
1542 * set *logfd to the file descriptor opened for appending to the file.
1543 * If no logfile exists and we decided not to create one, return 0 and
1544 * set *logfd to -1. On failure, fill in *err, set *logfd to -1, and
1547 static int log_ref_setup(struct files_ref_store
*refs
,
1548 const char *refname
, int force_create
,
1549 int *logfd
, struct strbuf
*err
)
1551 struct strbuf logfile_sb
= STRBUF_INIT
;
1554 files_reflog_path(refs
, &logfile_sb
, refname
);
1555 logfile
= strbuf_detach(&logfile_sb
, NULL
);
1557 if (force_create
|| should_autocreate_reflog(refname
)) {
1558 if (raceproof_create_file(logfile
, open_or_create_logfile
, logfd
)) {
1559 if (errno
== ENOENT
)
1560 strbuf_addf(err
, "unable to create directory for '%s': "
1561 "%s", logfile
, strerror(errno
));
1562 else if (errno
== EISDIR
)
1563 strbuf_addf(err
, "there are still logs under '%s'",
1566 strbuf_addf(err
, "unable to append to '%s': %s",
1567 logfile
, strerror(errno
));
1572 *logfd
= open(logfile
, O_APPEND
| O_WRONLY
, 0666);
1574 if (errno
== ENOENT
|| errno
== EISDIR
) {
1576 * The logfile doesn't already exist,
1577 * but that is not an error; it only
1578 * means that we won't write log
1583 strbuf_addf(err
, "unable to append to '%s': %s",
1584 logfile
, strerror(errno
));
1591 adjust_shared_perm(logfile
);
1601 static int files_create_reflog(struct ref_store
*ref_store
,
1602 const char *refname
, int force_create
,
1605 struct files_ref_store
*refs
=
1606 files_downcast(ref_store
, REF_STORE_WRITE
, "create_reflog");
1609 if (log_ref_setup(refs
, refname
, force_create
, &fd
, err
))
1618 static int log_ref_write_fd(int fd
, const struct object_id
*old_oid
,
1619 const struct object_id
*new_oid
,
1620 const char *committer
, const char *msg
)
1622 struct strbuf sb
= STRBUF_INIT
;
1625 strbuf_addf(&sb
, "%s %s %s", oid_to_hex(old_oid
), oid_to_hex(new_oid
), committer
);
1627 copy_reflog_msg(&sb
, msg
);
1628 strbuf_addch(&sb
, '\n');
1629 if (write_in_full(fd
, sb
.buf
, sb
.len
) < 0)
1631 strbuf_release(&sb
);
1635 static int files_log_ref_write(struct files_ref_store
*refs
,
1636 const char *refname
, const struct object_id
*old_oid
,
1637 const struct object_id
*new_oid
, const char *msg
,
1638 int flags
, struct strbuf
*err
)
1642 if (log_all_ref_updates
== LOG_REFS_UNSET
)
1643 log_all_ref_updates
= is_bare_repository() ? LOG_REFS_NONE
: LOG_REFS_NORMAL
;
1645 result
= log_ref_setup(refs
, refname
,
1646 flags
& REF_FORCE_CREATE_REFLOG
,
1654 result
= log_ref_write_fd(logfd
, old_oid
, new_oid
,
1655 git_committer_info(0), msg
);
1657 struct strbuf sb
= STRBUF_INIT
;
1658 int save_errno
= errno
;
1660 files_reflog_path(refs
, &sb
, refname
);
1661 strbuf_addf(err
, "unable to append to '%s': %s",
1662 sb
.buf
, strerror(save_errno
));
1663 strbuf_release(&sb
);
1668 struct strbuf sb
= STRBUF_INIT
;
1669 int save_errno
= errno
;
1671 files_reflog_path(refs
, &sb
, refname
);
1672 strbuf_addf(err
, "unable to append to '%s': %s",
1673 sb
.buf
, strerror(save_errno
));
1674 strbuf_release(&sb
);
1681 * Write oid into the open lockfile, then close the lockfile. On
1682 * errors, rollback the lockfile, fill in *err and return -1.
1684 static int write_ref_to_lockfile(struct ref_lock
*lock
,
1685 const struct object_id
*oid
, struct strbuf
*err
)
1687 static char term
= '\n';
1691 o
= parse_object(the_repository
, oid
);
1694 "trying to write ref '%s' with nonexistent object %s",
1695 lock
->ref_name
, oid_to_hex(oid
));
1699 if (o
->type
!= OBJ_COMMIT
&& is_branch(lock
->ref_name
)) {
1701 "trying to write non-commit object %s to branch '%s'",
1702 oid_to_hex(oid
), lock
->ref_name
);
1706 fd
= get_lock_file_fd(&lock
->lk
);
1707 if (write_in_full(fd
, oid_to_hex(oid
), the_hash_algo
->hexsz
) < 0 ||
1708 write_in_full(fd
, &term
, 1) < 0 ||
1709 close_ref_gently(lock
) < 0) {
1711 "couldn't write '%s'", get_lock_file_path(&lock
->lk
));
1719 * Commit a change to a loose reference that has already been written
1720 * to the loose reference lockfile. Also update the reflogs if
1721 * necessary, using the specified lockmsg (which can be NULL).
1723 static int commit_ref_update(struct files_ref_store
*refs
,
1724 struct ref_lock
*lock
,
1725 const struct object_id
*oid
, const char *logmsg
,
1728 files_assert_main_repository(refs
, "commit_ref_update");
1730 clear_loose_ref_cache(refs
);
1731 if (files_log_ref_write(refs
, lock
->ref_name
,
1732 &lock
->old_oid
, oid
,
1734 char *old_msg
= strbuf_detach(err
, NULL
);
1735 strbuf_addf(err
, "cannot update the ref '%s': %s",
1736 lock
->ref_name
, old_msg
);
1742 if (strcmp(lock
->ref_name
, "HEAD") != 0) {
1744 * Special hack: If a branch is updated directly and HEAD
1745 * points to it (may happen on the remote side of a push
1746 * for example) then logically the HEAD reflog should be
1748 * A generic solution implies reverse symref information,
1749 * but finding all symrefs pointing to the given branch
1750 * would be rather costly for this rare event (the direct
1751 * update of a branch) to be worth it. So let's cheat and
1752 * check with HEAD only which should cover 99% of all usage
1753 * scenarios (even 100% of the default ones).
1756 const char *head_ref
;
1758 head_ref
= refs_resolve_ref_unsafe(&refs
->base
, "HEAD",
1759 RESOLVE_REF_READING
,
1761 if (head_ref
&& (head_flag
& REF_ISSYMREF
) &&
1762 !strcmp(head_ref
, lock
->ref_name
)) {
1763 struct strbuf log_err
= STRBUF_INIT
;
1764 if (files_log_ref_write(refs
, "HEAD",
1765 &lock
->old_oid
, oid
,
1766 logmsg
, 0, &log_err
)) {
1767 error("%s", log_err
.buf
);
1768 strbuf_release(&log_err
);
1773 if (commit_ref(lock
)) {
1774 strbuf_addf(err
, "couldn't set '%s'", lock
->ref_name
);
1783 static int create_ref_symlink(struct ref_lock
*lock
, const char *target
)
1786 #ifndef NO_SYMLINK_HEAD
1787 char *ref_path
= get_locked_file_path(&lock
->lk
);
1789 ret
= symlink(target
, ref_path
);
1793 fprintf(stderr
, "no symlink - falling back to symbolic ref\n");
1798 static void update_symref_reflog(struct files_ref_store
*refs
,
1799 struct ref_lock
*lock
, const char *refname
,
1800 const char *target
, const char *logmsg
)
1802 struct strbuf err
= STRBUF_INIT
;
1803 struct object_id new_oid
;
1805 !refs_read_ref_full(&refs
->base
, target
,
1806 RESOLVE_REF_READING
, &new_oid
, NULL
) &&
1807 files_log_ref_write(refs
, refname
, &lock
->old_oid
,
1808 &new_oid
, logmsg
, 0, &err
)) {
1809 error("%s", err
.buf
);
1810 strbuf_release(&err
);
1814 static int create_symref_locked(struct files_ref_store
*refs
,
1815 struct ref_lock
*lock
, const char *refname
,
1816 const char *target
, const char *logmsg
)
1818 if (prefer_symlink_refs
&& !create_ref_symlink(lock
, target
)) {
1819 update_symref_reflog(refs
, lock
, refname
, target
, logmsg
);
1823 if (!fdopen_lock_file(&lock
->lk
, "w"))
1824 return error("unable to fdopen %s: %s",
1825 lock
->lk
.tempfile
->filename
.buf
, strerror(errno
));
1827 update_symref_reflog(refs
, lock
, refname
, target
, logmsg
);
1829 /* no error check; commit_ref will check ferror */
1830 fprintf(lock
->lk
.tempfile
->fp
, "ref: %s\n", target
);
1831 if (commit_ref(lock
) < 0)
1832 return error("unable to write symref for %s: %s", refname
,
1837 static int files_create_symref(struct ref_store
*ref_store
,
1838 const char *refname
, const char *target
,
1841 struct files_ref_store
*refs
=
1842 files_downcast(ref_store
, REF_STORE_WRITE
, "create_symref");
1843 struct strbuf err
= STRBUF_INIT
;
1844 struct ref_lock
*lock
;
1847 lock
= lock_ref_oid_basic(refs
, refname
, NULL
,
1848 NULL
, NULL
, REF_NO_DEREF
, NULL
,
1851 error("%s", err
.buf
);
1852 strbuf_release(&err
);
1856 ret
= create_symref_locked(refs
, lock
, refname
, target
, logmsg
);
1861 static int files_reflog_exists(struct ref_store
*ref_store
,
1862 const char *refname
)
1864 struct files_ref_store
*refs
=
1865 files_downcast(ref_store
, REF_STORE_READ
, "reflog_exists");
1866 struct strbuf sb
= STRBUF_INIT
;
1870 files_reflog_path(refs
, &sb
, refname
);
1871 ret
= !lstat(sb
.buf
, &st
) && S_ISREG(st
.st_mode
);
1872 strbuf_release(&sb
);
1876 static int files_delete_reflog(struct ref_store
*ref_store
,
1877 const char *refname
)
1879 struct files_ref_store
*refs
=
1880 files_downcast(ref_store
, REF_STORE_WRITE
, "delete_reflog");
1881 struct strbuf sb
= STRBUF_INIT
;
1884 files_reflog_path(refs
, &sb
, refname
);
1885 ret
= remove_path(sb
.buf
);
1886 strbuf_release(&sb
);
1890 static int show_one_reflog_ent(struct strbuf
*sb
, each_reflog_ent_fn fn
, void *cb_data
)
1892 struct object_id ooid
, noid
;
1893 char *email_end
, *message
;
1894 timestamp_t timestamp
;
1896 const char *p
= sb
->buf
;
1898 /* old SP new SP name <email> SP time TAB msg LF */
1899 if (!sb
->len
|| sb
->buf
[sb
->len
- 1] != '\n' ||
1900 parse_oid_hex(p
, &ooid
, &p
) || *p
++ != ' ' ||
1901 parse_oid_hex(p
, &noid
, &p
) || *p
++ != ' ' ||
1902 !(email_end
= strchr(p
, '>')) ||
1903 email_end
[1] != ' ' ||
1904 !(timestamp
= parse_timestamp(email_end
+ 2, &message
, 10)) ||
1905 !message
|| message
[0] != ' ' ||
1906 (message
[1] != '+' && message
[1] != '-') ||
1907 !isdigit(message
[2]) || !isdigit(message
[3]) ||
1908 !isdigit(message
[4]) || !isdigit(message
[5]))
1909 return 0; /* corrupt? */
1910 email_end
[1] = '\0';
1911 tz
= strtol(message
+ 1, NULL
, 10);
1912 if (message
[6] != '\t')
1916 return fn(&ooid
, &noid
, p
, timestamp
, tz
, message
, cb_data
);
1919 static char *find_beginning_of_line(char *bob
, char *scan
)
1921 while (bob
< scan
&& *(--scan
) != '\n')
1922 ; /* keep scanning backwards */
1924 * Return either beginning of the buffer, or LF at the end of
1925 * the previous line.
1930 static int files_for_each_reflog_ent_reverse(struct ref_store
*ref_store
,
1931 const char *refname
,
1932 each_reflog_ent_fn fn
,
1935 struct files_ref_store
*refs
=
1936 files_downcast(ref_store
, REF_STORE_READ
,
1937 "for_each_reflog_ent_reverse");
1938 struct strbuf sb
= STRBUF_INIT
;
1941 int ret
= 0, at_tail
= 1;
1943 files_reflog_path(refs
, &sb
, refname
);
1944 logfp
= fopen(sb
.buf
, "r");
1945 strbuf_release(&sb
);
1949 /* Jump to the end */
1950 if (fseek(logfp
, 0, SEEK_END
) < 0)
1951 ret
= error("cannot seek back reflog for %s: %s",
1952 refname
, strerror(errno
));
1954 while (!ret
&& 0 < pos
) {
1960 /* Fill next block from the end */
1961 cnt
= (sizeof(buf
) < pos
) ? sizeof(buf
) : pos
;
1962 if (fseek(logfp
, pos
- cnt
, SEEK_SET
)) {
1963 ret
= error("cannot seek back reflog for %s: %s",
1964 refname
, strerror(errno
));
1967 nread
= fread(buf
, cnt
, 1, logfp
);
1969 ret
= error("cannot read %d bytes from reflog for %s: %s",
1970 cnt
, refname
, strerror(errno
));
1975 scanp
= endp
= buf
+ cnt
;
1976 if (at_tail
&& scanp
[-1] == '\n')
1977 /* Looking at the final LF at the end of the file */
1981 while (buf
< scanp
) {
1983 * terminating LF of the previous line, or the beginning
1988 bp
= find_beginning_of_line(buf
, scanp
);
1992 * The newline is the end of the previous line,
1993 * so we know we have complete line starting
1994 * at (bp + 1). Prefix it onto any prior data
1995 * we collected for the line and process it.
1997 strbuf_splice(&sb
, 0, 0, bp
+ 1, endp
- (bp
+ 1));
2000 ret
= show_one_reflog_ent(&sb
, fn
, cb_data
);
2006 * We are at the start of the buffer, and the
2007 * start of the file; there is no previous
2008 * line, and we have everything for this one.
2009 * Process it, and we can end the loop.
2011 strbuf_splice(&sb
, 0, 0, buf
, endp
- buf
);
2012 ret
= show_one_reflog_ent(&sb
, fn
, cb_data
);
2019 * We are at the start of the buffer, and there
2020 * is more file to read backwards. Which means
2021 * we are in the middle of a line. Note that we
2022 * may get here even if *bp was a newline; that
2023 * just means we are at the exact end of the
2024 * previous line, rather than some spot in the
2027 * Save away what we have to be combined with
2028 * the data from the next read.
2030 strbuf_splice(&sb
, 0, 0, buf
, endp
- buf
);
2037 BUG("reverse reflog parser had leftover data");
2040 strbuf_release(&sb
);
2044 static int files_for_each_reflog_ent(struct ref_store
*ref_store
,
2045 const char *refname
,
2046 each_reflog_ent_fn fn
, void *cb_data
)
2048 struct files_ref_store
*refs
=
2049 files_downcast(ref_store
, REF_STORE_READ
,
2050 "for_each_reflog_ent");
2052 struct strbuf sb
= STRBUF_INIT
;
2055 files_reflog_path(refs
, &sb
, refname
);
2056 logfp
= fopen(sb
.buf
, "r");
2057 strbuf_release(&sb
);
2061 while (!ret
&& !strbuf_getwholeline(&sb
, logfp
, '\n'))
2062 ret
= show_one_reflog_ent(&sb
, fn
, cb_data
);
2064 strbuf_release(&sb
);
2068 struct files_reflog_iterator
{
2069 struct ref_iterator base
;
2071 struct ref_store
*ref_store
;
2072 struct dir_iterator
*dir_iterator
;
2073 struct object_id oid
;
2076 static int files_reflog_iterator_advance(struct ref_iterator
*ref_iterator
)
2078 struct files_reflog_iterator
*iter
=
2079 (struct files_reflog_iterator
*)ref_iterator
;
2080 struct dir_iterator
*diter
= iter
->dir_iterator
;
2083 while ((ok
= dir_iterator_advance(diter
)) == ITER_OK
) {
2086 if (!S_ISREG(diter
->st
.st_mode
))
2088 if (diter
->basename
[0] == '.')
2090 if (ends_with(diter
->basename
, ".lock"))
2093 if (refs_read_ref_full(iter
->ref_store
,
2094 diter
->relative_path
, 0,
2095 &iter
->oid
, &flags
)) {
2096 error("bad ref for %s", diter
->path
.buf
);
2100 iter
->base
.refname
= diter
->relative_path
;
2101 iter
->base
.oid
= &iter
->oid
;
2102 iter
->base
.flags
= flags
;
2106 iter
->dir_iterator
= NULL
;
2107 if (ref_iterator_abort(ref_iterator
) == ITER_ERROR
)
2112 static int files_reflog_iterator_peel(struct ref_iterator
*ref_iterator
,
2113 struct object_id
*peeled
)
2115 BUG("ref_iterator_peel() called for reflog_iterator");
2118 static int files_reflog_iterator_abort(struct ref_iterator
*ref_iterator
)
2120 struct files_reflog_iterator
*iter
=
2121 (struct files_reflog_iterator
*)ref_iterator
;
2124 if (iter
->dir_iterator
)
2125 ok
= dir_iterator_abort(iter
->dir_iterator
);
2127 base_ref_iterator_free(ref_iterator
);
2131 static struct ref_iterator_vtable files_reflog_iterator_vtable
= {
2132 files_reflog_iterator_advance
,
2133 files_reflog_iterator_peel
,
2134 files_reflog_iterator_abort
2137 static struct ref_iterator
*reflog_iterator_begin(struct ref_store
*ref_store
,
2140 struct files_reflog_iterator
*iter
= xcalloc(1, sizeof(*iter
));
2141 struct ref_iterator
*ref_iterator
= &iter
->base
;
2142 struct strbuf sb
= STRBUF_INIT
;
2144 base_ref_iterator_init(ref_iterator
, &files_reflog_iterator_vtable
, 0);
2145 strbuf_addf(&sb
, "%s/logs", gitdir
);
2146 iter
->dir_iterator
= dir_iterator_begin(sb
.buf
);
2147 iter
->ref_store
= ref_store
;
2148 strbuf_release(&sb
);
2150 return ref_iterator
;
2153 static enum iterator_selection
reflog_iterator_select(
2154 struct ref_iterator
*iter_worktree
,
2155 struct ref_iterator
*iter_common
,
2158 if (iter_worktree
) {
2160 * We're a bit loose here. We probably should ignore
2161 * common refs if they are accidentally added as
2162 * per-worktree refs.
2164 return ITER_SELECT_0
;
2165 } else if (iter_common
) {
2166 if (ref_type(iter_common
->refname
) == REF_TYPE_NORMAL
)
2167 return ITER_SELECT_1
;
2170 * The main ref store may contain main worktree's
2171 * per-worktree refs, which should be ignored
2178 static struct ref_iterator
*files_reflog_iterator_begin(struct ref_store
*ref_store
)
2180 struct files_ref_store
*refs
=
2181 files_downcast(ref_store
, REF_STORE_READ
,
2182 "reflog_iterator_begin");
2184 if (!strcmp(refs
->gitdir
, refs
->gitcommondir
)) {
2185 return reflog_iterator_begin(ref_store
, refs
->gitcommondir
);
2187 return merge_ref_iterator_begin(
2189 reflog_iterator_begin(ref_store
, refs
->gitdir
),
2190 reflog_iterator_begin(ref_store
, refs
->gitcommondir
),
2191 reflog_iterator_select
, refs
);
2196 * If update is a direct update of head_ref (the reference pointed to
2197 * by HEAD), then add an extra REF_LOG_ONLY update for HEAD.
2199 static int split_head_update(struct ref_update
*update
,
2200 struct ref_transaction
*transaction
,
2201 const char *head_ref
,
2202 struct string_list
*affected_refnames
,
2205 struct string_list_item
*item
;
2206 struct ref_update
*new_update
;
2208 if ((update
->flags
& REF_LOG_ONLY
) ||
2209 (update
->flags
& REF_IS_PRUNING
) ||
2210 (update
->flags
& REF_UPDATE_VIA_HEAD
))
2213 if (strcmp(update
->refname
, head_ref
))
2217 * First make sure that HEAD is not already in the
2218 * transaction. This check is O(lg N) in the transaction
2219 * size, but it happens at most once per transaction.
2221 if (string_list_has_string(affected_refnames
, "HEAD")) {
2222 /* An entry already existed */
2224 "multiple updates for 'HEAD' (including one "
2225 "via its referent '%s') are not allowed",
2227 return TRANSACTION_NAME_CONFLICT
;
2230 new_update
= ref_transaction_add_update(
2231 transaction
, "HEAD",
2232 update
->flags
| REF_LOG_ONLY
| REF_NO_DEREF
,
2233 &update
->new_oid
, &update
->old_oid
,
2237 * Add "HEAD". This insertion is O(N) in the transaction
2238 * size, but it happens at most once per transaction.
2239 * Add new_update->refname instead of a literal "HEAD".
2241 if (strcmp(new_update
->refname
, "HEAD"))
2242 BUG("%s unexpectedly not 'HEAD'", new_update
->refname
);
2243 item
= string_list_insert(affected_refnames
, new_update
->refname
);
2244 item
->util
= new_update
;
2250 * update is for a symref that points at referent and doesn't have
2251 * REF_NO_DEREF set. Split it into two updates:
2252 * - The original update, but with REF_LOG_ONLY and REF_NO_DEREF set
2253 * - A new, separate update for the referent reference
2254 * Note that the new update will itself be subject to splitting when
2255 * the iteration gets to it.
2257 static int split_symref_update(struct files_ref_store
*refs
,
2258 struct ref_update
*update
,
2259 const char *referent
,
2260 struct ref_transaction
*transaction
,
2261 struct string_list
*affected_refnames
,
2264 struct string_list_item
*item
;
2265 struct ref_update
*new_update
;
2266 unsigned int new_flags
;
2269 * First make sure that referent is not already in the
2270 * transaction. This check is O(lg N) in the transaction
2271 * size, but it happens at most once per symref in a
2274 if (string_list_has_string(affected_refnames
, referent
)) {
2275 /* An entry already exists */
2277 "multiple updates for '%s' (including one "
2278 "via symref '%s') are not allowed",
2279 referent
, update
->refname
);
2280 return TRANSACTION_NAME_CONFLICT
;
2283 new_flags
= update
->flags
;
2284 if (!strcmp(update
->refname
, "HEAD")) {
2286 * Record that the new update came via HEAD, so that
2287 * when we process it, split_head_update() doesn't try
2288 * to add another reflog update for HEAD. Note that
2289 * this bit will be propagated if the new_update
2290 * itself needs to be split.
2292 new_flags
|= REF_UPDATE_VIA_HEAD
;
2295 new_update
= ref_transaction_add_update(
2296 transaction
, referent
, new_flags
,
2297 &update
->new_oid
, &update
->old_oid
,
2300 new_update
->parent_update
= update
;
2303 * Change the symbolic ref update to log only. Also, it
2304 * doesn't need to check its old OID value, as that will be
2305 * done when new_update is processed.
2307 update
->flags
|= REF_LOG_ONLY
| REF_NO_DEREF
;
2308 update
->flags
&= ~REF_HAVE_OLD
;
2311 * Add the referent. This insertion is O(N) in the transaction
2312 * size, but it happens at most once per symref in a
2313 * transaction. Make sure to add new_update->refname, which will
2314 * be valid as long as affected_refnames is in use, and NOT
2315 * referent, which might soon be freed by our caller.
2317 item
= string_list_insert(affected_refnames
, new_update
->refname
);
2319 BUG("%s unexpectedly found in affected_refnames",
2320 new_update
->refname
);
2321 item
->util
= new_update
;
2327 * Return the refname under which update was originally requested.
2329 static const char *original_update_refname(struct ref_update
*update
)
2331 while (update
->parent_update
)
2332 update
= update
->parent_update
;
2334 return update
->refname
;
2338 * Check whether the REF_HAVE_OLD and old_oid values stored in update
2339 * are consistent with oid, which is the reference's current value. If
2340 * everything is OK, return 0; otherwise, write an error message to
2341 * err and return -1.
2343 static int check_old_oid(struct ref_update
*update
, struct object_id
*oid
,
2346 if (!(update
->flags
& REF_HAVE_OLD
) ||
2347 oideq(oid
, &update
->old_oid
))
2350 if (is_null_oid(&update
->old_oid
))
2351 strbuf_addf(err
, "cannot lock ref '%s': "
2352 "reference already exists",
2353 original_update_refname(update
));
2354 else if (is_null_oid(oid
))
2355 strbuf_addf(err
, "cannot lock ref '%s': "
2356 "reference is missing but expected %s",
2357 original_update_refname(update
),
2358 oid_to_hex(&update
->old_oid
));
2360 strbuf_addf(err
, "cannot lock ref '%s': "
2361 "is at %s but expected %s",
2362 original_update_refname(update
),
2364 oid_to_hex(&update
->old_oid
));
2370 * Prepare for carrying out update:
2371 * - Lock the reference referred to by update.
2372 * - Read the reference under lock.
2373 * - Check that its old OID value (if specified) is correct, and in
2374 * any case record it in update->lock->old_oid for later use when
2375 * writing the reflog.
2376 * - If it is a symref update without REF_NO_DEREF, split it up into a
2377 * REF_LOG_ONLY update of the symref and add a separate update for
2378 * the referent to transaction.
2379 * - If it is an update of head_ref, add a corresponding REF_LOG_ONLY
2382 static int lock_ref_for_update(struct files_ref_store
*refs
,
2383 struct ref_update
*update
,
2384 struct ref_transaction
*transaction
,
2385 const char *head_ref
,
2386 struct string_list
*affected_refnames
,
2389 struct strbuf referent
= STRBUF_INIT
;
2390 int mustexist
= (update
->flags
& REF_HAVE_OLD
) &&
2391 !is_null_oid(&update
->old_oid
);
2393 struct ref_lock
*lock
;
2395 files_assert_main_repository(refs
, "lock_ref_for_update");
2397 if ((update
->flags
& REF_HAVE_NEW
) && is_null_oid(&update
->new_oid
))
2398 update
->flags
|= REF_DELETING
;
2401 ret
= split_head_update(update
, transaction
, head_ref
,
2402 affected_refnames
, err
);
2407 ret
= lock_raw_ref(refs
, update
->refname
, mustexist
,
2408 affected_refnames
, NULL
,
2410 &update
->type
, err
);
2414 reason
= strbuf_detach(err
, NULL
);
2415 strbuf_addf(err
, "cannot lock ref '%s': %s",
2416 original_update_refname(update
), reason
);
2421 update
->backend_data
= lock
;
2423 if (update
->type
& REF_ISSYMREF
) {
2424 if (update
->flags
& REF_NO_DEREF
) {
2426 * We won't be reading the referent as part of
2427 * the transaction, so we have to read it here
2428 * to record and possibly check old_oid:
2430 if (refs_read_ref_full(&refs
->base
,
2432 &lock
->old_oid
, NULL
)) {
2433 if (update
->flags
& REF_HAVE_OLD
) {
2434 strbuf_addf(err
, "cannot lock ref '%s': "
2435 "error reading reference",
2436 original_update_refname(update
));
2437 ret
= TRANSACTION_GENERIC_ERROR
;
2440 } else if (check_old_oid(update
, &lock
->old_oid
, err
)) {
2441 ret
= TRANSACTION_GENERIC_ERROR
;
2446 * Create a new update for the reference this
2447 * symref is pointing at. Also, we will record
2448 * and verify old_oid for this update as part
2449 * of processing the split-off update, so we
2450 * don't have to do it here.
2452 ret
= split_symref_update(refs
, update
,
2453 referent
.buf
, transaction
,
2454 affected_refnames
, err
);
2459 struct ref_update
*parent_update
;
2461 if (check_old_oid(update
, &lock
->old_oid
, err
)) {
2462 ret
= TRANSACTION_GENERIC_ERROR
;
2467 * If this update is happening indirectly because of a
2468 * symref update, record the old OID in the parent
2471 for (parent_update
= update
->parent_update
;
2473 parent_update
= parent_update
->parent_update
) {
2474 struct ref_lock
*parent_lock
= parent_update
->backend_data
;
2475 oidcpy(&parent_lock
->old_oid
, &lock
->old_oid
);
2479 if ((update
->flags
& REF_HAVE_NEW
) &&
2480 !(update
->flags
& REF_DELETING
) &&
2481 !(update
->flags
& REF_LOG_ONLY
)) {
2482 if (!(update
->type
& REF_ISSYMREF
) &&
2483 oideq(&lock
->old_oid
, &update
->new_oid
)) {
2485 * The reference already has the desired
2486 * value, so we don't need to write it.
2488 } else if (write_ref_to_lockfile(lock
, &update
->new_oid
,
2490 char *write_err
= strbuf_detach(err
, NULL
);
2493 * The lock was freed upon failure of
2494 * write_ref_to_lockfile():
2496 update
->backend_data
= NULL
;
2498 "cannot update ref '%s': %s",
2499 update
->refname
, write_err
);
2501 ret
= TRANSACTION_GENERIC_ERROR
;
2504 update
->flags
|= REF_NEEDS_COMMIT
;
2507 if (!(update
->flags
& REF_NEEDS_COMMIT
)) {
2509 * We didn't call write_ref_to_lockfile(), so
2510 * the lockfile is still open. Close it to
2511 * free up the file descriptor:
2513 if (close_ref_gently(lock
)) {
2514 strbuf_addf(err
, "couldn't close '%s.lock'",
2516 ret
= TRANSACTION_GENERIC_ERROR
;
2522 strbuf_release(&referent
);
2526 struct files_transaction_backend_data
{
2527 struct ref_transaction
*packed_transaction
;
2528 int packed_refs_locked
;
2532 * Unlock any references in `transaction` that are still locked, and
2533 * mark the transaction closed.
2535 static void files_transaction_cleanup(struct files_ref_store
*refs
,
2536 struct ref_transaction
*transaction
)
2539 struct files_transaction_backend_data
*backend_data
=
2540 transaction
->backend_data
;
2541 struct strbuf err
= STRBUF_INIT
;
2543 for (i
= 0; i
< transaction
->nr
; i
++) {
2544 struct ref_update
*update
= transaction
->updates
[i
];
2545 struct ref_lock
*lock
= update
->backend_data
;
2549 update
->backend_data
= NULL
;
2553 if (backend_data
->packed_transaction
&&
2554 ref_transaction_abort(backend_data
->packed_transaction
, &err
)) {
2555 error("error aborting transaction: %s", err
.buf
);
2556 strbuf_release(&err
);
2559 if (backend_data
->packed_refs_locked
)
2560 packed_refs_unlock(refs
->packed_ref_store
);
2564 transaction
->state
= REF_TRANSACTION_CLOSED
;
2567 static int files_transaction_prepare(struct ref_store
*ref_store
,
2568 struct ref_transaction
*transaction
,
2571 struct files_ref_store
*refs
=
2572 files_downcast(ref_store
, REF_STORE_WRITE
,
2573 "ref_transaction_prepare");
2576 struct string_list affected_refnames
= STRING_LIST_INIT_NODUP
;
2577 char *head_ref
= NULL
;
2579 struct files_transaction_backend_data
*backend_data
;
2580 struct ref_transaction
*packed_transaction
= NULL
;
2584 if (!transaction
->nr
)
2587 backend_data
= xcalloc(1, sizeof(*backend_data
));
2588 transaction
->backend_data
= backend_data
;
2591 * Fail if a refname appears more than once in the
2592 * transaction. (If we end up splitting up any updates using
2593 * split_symref_update() or split_head_update(), those
2594 * functions will check that the new updates don't have the
2595 * same refname as any existing ones.) Also fail if any of the
2596 * updates use REF_IS_PRUNING without REF_NO_DEREF.
2598 for (i
= 0; i
< transaction
->nr
; i
++) {
2599 struct ref_update
*update
= transaction
->updates
[i
];
2600 struct string_list_item
*item
=
2601 string_list_append(&affected_refnames
, update
->refname
);
2603 if ((update
->flags
& REF_IS_PRUNING
) &&
2604 !(update
->flags
& REF_NO_DEREF
))
2605 BUG("REF_IS_PRUNING set without REF_NO_DEREF");
2608 * We store a pointer to update in item->util, but at
2609 * the moment we never use the value of this field
2610 * except to check whether it is non-NULL.
2612 item
->util
= update
;
2614 string_list_sort(&affected_refnames
);
2615 if (ref_update_reject_duplicates(&affected_refnames
, err
)) {
2616 ret
= TRANSACTION_GENERIC_ERROR
;
2621 * Special hack: If a branch is updated directly and HEAD
2622 * points to it (may happen on the remote side of a push
2623 * for example) then logically the HEAD reflog should be
2626 * A generic solution would require reverse symref lookups,
2627 * but finding all symrefs pointing to a given branch would be
2628 * rather costly for this rare event (the direct update of a
2629 * branch) to be worth it. So let's cheat and check with HEAD
2630 * only, which should cover 99% of all usage scenarios (even
2631 * 100% of the default ones).
2633 * So if HEAD is a symbolic reference, then record the name of
2634 * the reference that it points to. If we see an update of
2635 * head_ref within the transaction, then split_head_update()
2636 * arranges for the reflog of HEAD to be updated, too.
2638 head_ref
= refs_resolve_refdup(ref_store
, "HEAD",
2639 RESOLVE_REF_NO_RECURSE
,
2642 if (head_ref
&& !(head_type
& REF_ISSYMREF
)) {
2643 FREE_AND_NULL(head_ref
);
2647 * Acquire all locks, verify old values if provided, check
2648 * that new values are valid, and write new values to the
2649 * lockfiles, ready to be activated. Only keep one lockfile
2650 * open at a time to avoid running out of file descriptors.
2651 * Note that lock_ref_for_update() might append more updates
2652 * to the transaction.
2654 for (i
= 0; i
< transaction
->nr
; i
++) {
2655 struct ref_update
*update
= transaction
->updates
[i
];
2657 ret
= lock_ref_for_update(refs
, update
, transaction
,
2658 head_ref
, &affected_refnames
, err
);
2662 if (update
->flags
& REF_DELETING
&&
2663 !(update
->flags
& REF_LOG_ONLY
) &&
2664 !(update
->flags
& REF_IS_PRUNING
)) {
2666 * This reference has to be deleted from
2667 * packed-refs if it exists there.
2669 if (!packed_transaction
) {
2670 packed_transaction
= ref_store_transaction_begin(
2671 refs
->packed_ref_store
, err
);
2672 if (!packed_transaction
) {
2673 ret
= TRANSACTION_GENERIC_ERROR
;
2677 backend_data
->packed_transaction
=
2681 ref_transaction_add_update(
2682 packed_transaction
, update
->refname
,
2683 REF_HAVE_NEW
| REF_NO_DEREF
,
2684 &update
->new_oid
, NULL
,
2689 if (packed_transaction
) {
2690 if (packed_refs_lock(refs
->packed_ref_store
, 0, err
)) {
2691 ret
= TRANSACTION_GENERIC_ERROR
;
2694 backend_data
->packed_refs_locked
= 1;
2696 if (is_packed_transaction_needed(refs
->packed_ref_store
,
2697 packed_transaction
)) {
2698 ret
= ref_transaction_prepare(packed_transaction
, err
);
2701 * We can skip rewriting the `packed-refs`
2702 * file. But we do need to leave it locked, so
2703 * that somebody else doesn't pack a reference
2704 * that we are trying to delete.
2706 if (ref_transaction_abort(packed_transaction
, err
)) {
2707 ret
= TRANSACTION_GENERIC_ERROR
;
2710 backend_data
->packed_transaction
= NULL
;
2716 string_list_clear(&affected_refnames
, 0);
2719 files_transaction_cleanup(refs
, transaction
);
2721 transaction
->state
= REF_TRANSACTION_PREPARED
;
2726 static int files_transaction_finish(struct ref_store
*ref_store
,
2727 struct ref_transaction
*transaction
,
2730 struct files_ref_store
*refs
=
2731 files_downcast(ref_store
, 0, "ref_transaction_finish");
2734 struct strbuf sb
= STRBUF_INIT
;
2735 struct files_transaction_backend_data
*backend_data
;
2736 struct ref_transaction
*packed_transaction
;
2741 if (!transaction
->nr
) {
2742 transaction
->state
= REF_TRANSACTION_CLOSED
;
2746 backend_data
= transaction
->backend_data
;
2747 packed_transaction
= backend_data
->packed_transaction
;
2749 /* Perform updates first so live commits remain referenced */
2750 for (i
= 0; i
< transaction
->nr
; i
++) {
2751 struct ref_update
*update
= transaction
->updates
[i
];
2752 struct ref_lock
*lock
= update
->backend_data
;
2754 if (update
->flags
& REF_NEEDS_COMMIT
||
2755 update
->flags
& REF_LOG_ONLY
) {
2756 if (files_log_ref_write(refs
,
2760 update
->msg
, update
->flags
,
2762 char *old_msg
= strbuf_detach(err
, NULL
);
2764 strbuf_addf(err
, "cannot update the ref '%s': %s",
2765 lock
->ref_name
, old_msg
);
2768 update
->backend_data
= NULL
;
2769 ret
= TRANSACTION_GENERIC_ERROR
;
2773 if (update
->flags
& REF_NEEDS_COMMIT
) {
2774 clear_loose_ref_cache(refs
);
2775 if (commit_ref(lock
)) {
2776 strbuf_addf(err
, "couldn't set '%s'", lock
->ref_name
);
2778 update
->backend_data
= NULL
;
2779 ret
= TRANSACTION_GENERIC_ERROR
;
2786 * Now that updates are safely completed, we can perform
2787 * deletes. First delete the reflogs of any references that
2788 * will be deleted, since (in the unexpected event of an
2789 * error) leaving a reference without a reflog is less bad
2790 * than leaving a reflog without a reference (the latter is a
2791 * mildly invalid repository state):
2793 for (i
= 0; i
< transaction
->nr
; i
++) {
2794 struct ref_update
*update
= transaction
->updates
[i
];
2795 if (update
->flags
& REF_DELETING
&&
2796 !(update
->flags
& REF_LOG_ONLY
) &&
2797 !(update
->flags
& REF_IS_PRUNING
)) {
2799 files_reflog_path(refs
, &sb
, update
->refname
);
2800 if (!unlink_or_warn(sb
.buf
))
2801 try_remove_empty_parents(refs
, update
->refname
,
2802 REMOVE_EMPTY_PARENTS_REFLOG
);
2807 * Perform deletes now that updates are safely completed.
2809 * First delete any packed versions of the references, while
2810 * retaining the packed-refs lock:
2812 if (packed_transaction
) {
2813 ret
= ref_transaction_commit(packed_transaction
, err
);
2814 ref_transaction_free(packed_transaction
);
2815 packed_transaction
= NULL
;
2816 backend_data
->packed_transaction
= NULL
;
2821 /* Now delete the loose versions of the references: */
2822 for (i
= 0; i
< transaction
->nr
; i
++) {
2823 struct ref_update
*update
= transaction
->updates
[i
];
2824 struct ref_lock
*lock
= update
->backend_data
;
2826 if (update
->flags
& REF_DELETING
&&
2827 !(update
->flags
& REF_LOG_ONLY
)) {
2828 if (!(update
->type
& REF_ISPACKED
) ||
2829 update
->type
& REF_ISSYMREF
) {
2830 /* It is a loose reference. */
2832 files_ref_path(refs
, &sb
, lock
->ref_name
);
2833 if (unlink_or_msg(sb
.buf
, err
)) {
2834 ret
= TRANSACTION_GENERIC_ERROR
;
2837 update
->flags
|= REF_DELETED_LOOSE
;
2842 clear_loose_ref_cache(refs
);
2845 files_transaction_cleanup(refs
, transaction
);
2847 for (i
= 0; i
< transaction
->nr
; i
++) {
2848 struct ref_update
*update
= transaction
->updates
[i
];
2850 if (update
->flags
& REF_DELETED_LOOSE
) {
2852 * The loose reference was deleted. Delete any
2853 * empty parent directories. (Note that this
2854 * can only work because we have already
2855 * removed the lockfile.)
2857 try_remove_empty_parents(refs
, update
->refname
,
2858 REMOVE_EMPTY_PARENTS_REF
);
2862 strbuf_release(&sb
);
2866 static int files_transaction_abort(struct ref_store
*ref_store
,
2867 struct ref_transaction
*transaction
,
2870 struct files_ref_store
*refs
=
2871 files_downcast(ref_store
, 0, "ref_transaction_abort");
2873 files_transaction_cleanup(refs
, transaction
);
2877 static int ref_present(const char *refname
,
2878 const struct object_id
*oid
, int flags
, void *cb_data
)
2880 struct string_list
*affected_refnames
= cb_data
;
2882 return string_list_has_string(affected_refnames
, refname
);
2885 static int files_initial_transaction_commit(struct ref_store
*ref_store
,
2886 struct ref_transaction
*transaction
,
2889 struct files_ref_store
*refs
=
2890 files_downcast(ref_store
, REF_STORE_WRITE
,
2891 "initial_ref_transaction_commit");
2894 struct string_list affected_refnames
= STRING_LIST_INIT_NODUP
;
2895 struct ref_transaction
*packed_transaction
= NULL
;
2899 if (transaction
->state
!= REF_TRANSACTION_OPEN
)
2900 BUG("commit called for transaction that is not open");
2902 /* Fail if a refname appears more than once in the transaction: */
2903 for (i
= 0; i
< transaction
->nr
; i
++)
2904 string_list_append(&affected_refnames
,
2905 transaction
->updates
[i
]->refname
);
2906 string_list_sort(&affected_refnames
);
2907 if (ref_update_reject_duplicates(&affected_refnames
, err
)) {
2908 ret
= TRANSACTION_GENERIC_ERROR
;
2913 * It's really undefined to call this function in an active
2914 * repository or when there are existing references: we are
2915 * only locking and changing packed-refs, so (1) any
2916 * simultaneous processes might try to change a reference at
2917 * the same time we do, and (2) any existing loose versions of
2918 * the references that we are setting would have precedence
2919 * over our values. But some remote helpers create the remote
2920 * "HEAD" and "master" branches before calling this function,
2921 * so here we really only check that none of the references
2922 * that we are creating already exists.
2924 if (refs_for_each_rawref(&refs
->base
, ref_present
,
2925 &affected_refnames
))
2926 BUG("initial ref transaction called with existing refs");
2928 packed_transaction
= ref_store_transaction_begin(refs
->packed_ref_store
, err
);
2929 if (!packed_transaction
) {
2930 ret
= TRANSACTION_GENERIC_ERROR
;
2934 for (i
= 0; i
< transaction
->nr
; i
++) {
2935 struct ref_update
*update
= transaction
->updates
[i
];
2937 if ((update
->flags
& REF_HAVE_OLD
) &&
2938 !is_null_oid(&update
->old_oid
))
2939 BUG("initial ref transaction with old_sha1 set");
2940 if (refs_verify_refname_available(&refs
->base
, update
->refname
,
2941 &affected_refnames
, NULL
,
2943 ret
= TRANSACTION_NAME_CONFLICT
;
2948 * Add a reference creation for this reference to the
2949 * packed-refs transaction:
2951 ref_transaction_add_update(packed_transaction
, update
->refname
,
2952 update
->flags
& ~REF_HAVE_OLD
,
2953 &update
->new_oid
, &update
->old_oid
,
2957 if (packed_refs_lock(refs
->packed_ref_store
, 0, err
)) {
2958 ret
= TRANSACTION_GENERIC_ERROR
;
2962 if (initial_ref_transaction_commit(packed_transaction
, err
)) {
2963 ret
= TRANSACTION_GENERIC_ERROR
;
2966 packed_refs_unlock(refs
->packed_ref_store
);
2968 if (packed_transaction
)
2969 ref_transaction_free(packed_transaction
);
2970 transaction
->state
= REF_TRANSACTION_CLOSED
;
2971 string_list_clear(&affected_refnames
, 0);
2975 struct expire_reflog_cb
{
2977 reflog_expiry_should_prune_fn
*should_prune_fn
;
2980 struct object_id last_kept_oid
;
2983 static int expire_reflog_ent(struct object_id
*ooid
, struct object_id
*noid
,
2984 const char *email
, timestamp_t timestamp
, int tz
,
2985 const char *message
, void *cb_data
)
2987 struct expire_reflog_cb
*cb
= cb_data
;
2988 struct expire_reflog_policy_cb
*policy_cb
= cb
->policy_cb
;
2990 if (cb
->flags
& EXPIRE_REFLOGS_REWRITE
)
2991 ooid
= &cb
->last_kept_oid
;
2993 if ((*cb
->should_prune_fn
)(ooid
, noid
, email
, timestamp
, tz
,
2994 message
, policy_cb
)) {
2996 printf("would prune %s", message
);
2997 else if (cb
->flags
& EXPIRE_REFLOGS_VERBOSE
)
2998 printf("prune %s", message
);
3001 fprintf(cb
->newlog
, "%s %s %s %"PRItime
" %+05d\t%s",
3002 oid_to_hex(ooid
), oid_to_hex(noid
),
3003 email
, timestamp
, tz
, message
);
3004 oidcpy(&cb
->last_kept_oid
, noid
);
3006 if (cb
->flags
& EXPIRE_REFLOGS_VERBOSE
)
3007 printf("keep %s", message
);
3012 static int files_reflog_expire(struct ref_store
*ref_store
,
3013 const char *refname
, const struct object_id
*oid
,
3015 reflog_expiry_prepare_fn prepare_fn
,
3016 reflog_expiry_should_prune_fn should_prune_fn
,
3017 reflog_expiry_cleanup_fn cleanup_fn
,
3018 void *policy_cb_data
)
3020 struct files_ref_store
*refs
=
3021 files_downcast(ref_store
, REF_STORE_WRITE
, "reflog_expire");
3022 struct lock_file reflog_lock
= LOCK_INIT
;
3023 struct expire_reflog_cb cb
;
3024 struct ref_lock
*lock
;
3025 struct strbuf log_file_sb
= STRBUF_INIT
;
3029 struct strbuf err
= STRBUF_INIT
;
3031 memset(&cb
, 0, sizeof(cb
));
3033 cb
.policy_cb
= policy_cb_data
;
3034 cb
.should_prune_fn
= should_prune_fn
;
3037 * The reflog file is locked by holding the lock on the
3038 * reference itself, plus we might need to update the
3039 * reference if --updateref was specified:
3041 lock
= lock_ref_oid_basic(refs
, refname
, oid
,
3042 NULL
, NULL
, REF_NO_DEREF
,
3045 error("cannot lock ref '%s': %s", refname
, err
.buf
);
3046 strbuf_release(&err
);
3049 if (!refs_reflog_exists(ref_store
, refname
)) {
3054 files_reflog_path(refs
, &log_file_sb
, refname
);
3055 log_file
= strbuf_detach(&log_file_sb
, NULL
);
3056 if (!(flags
& EXPIRE_REFLOGS_DRY_RUN
)) {
3058 * Even though holding $GIT_DIR/logs/$reflog.lock has
3059 * no locking implications, we use the lock_file
3060 * machinery here anyway because it does a lot of the
3061 * work we need, including cleaning up if the program
3062 * exits unexpectedly.
3064 if (hold_lock_file_for_update(&reflog_lock
, log_file
, 0) < 0) {
3065 struct strbuf err
= STRBUF_INIT
;
3066 unable_to_lock_message(log_file
, errno
, &err
);
3067 error("%s", err
.buf
);
3068 strbuf_release(&err
);
3071 cb
.newlog
= fdopen_lock_file(&reflog_lock
, "w");
3073 error("cannot fdopen %s (%s)",
3074 get_lock_file_path(&reflog_lock
), strerror(errno
));
3079 (*prepare_fn
)(refname
, oid
, cb
.policy_cb
);
3080 refs_for_each_reflog_ent(ref_store
, refname
, expire_reflog_ent
, &cb
);
3081 (*cleanup_fn
)(cb
.policy_cb
);
3083 if (!(flags
& EXPIRE_REFLOGS_DRY_RUN
)) {
3085 * It doesn't make sense to adjust a reference pointed
3086 * to by a symbolic ref based on expiring entries in
3087 * the symbolic reference's reflog. Nor can we update
3088 * a reference if there are no remaining reflog
3091 int update
= (flags
& EXPIRE_REFLOGS_UPDATE_REF
) &&
3092 !(type
& REF_ISSYMREF
) &&
3093 !is_null_oid(&cb
.last_kept_oid
);
3095 if (close_lock_file_gently(&reflog_lock
)) {
3096 status
|= error("couldn't write %s: %s", log_file
,
3098 rollback_lock_file(&reflog_lock
);
3099 } else if (update
&&
3100 (write_in_full(get_lock_file_fd(&lock
->lk
),
3101 oid_to_hex(&cb
.last_kept_oid
), the_hash_algo
->hexsz
) < 0 ||
3102 write_str_in_full(get_lock_file_fd(&lock
->lk
), "\n") < 0 ||
3103 close_ref_gently(lock
) < 0)) {
3104 status
|= error("couldn't write %s",
3105 get_lock_file_path(&lock
->lk
));
3106 rollback_lock_file(&reflog_lock
);
3107 } else if (commit_lock_file(&reflog_lock
)) {
3108 status
|= error("unable to write reflog '%s' (%s)",
3109 log_file
, strerror(errno
));
3110 } else if (update
&& commit_ref(lock
)) {
3111 status
|= error("couldn't set %s", lock
->ref_name
);
3119 rollback_lock_file(&reflog_lock
);
3125 static int files_init_db(struct ref_store
*ref_store
, struct strbuf
*err
)
3127 struct files_ref_store
*refs
=
3128 files_downcast(ref_store
, REF_STORE_WRITE
, "init_db");
3129 struct strbuf sb
= STRBUF_INIT
;
3132 * Create .git/refs/{heads,tags}
3134 files_ref_path(refs
, &sb
, "refs/heads");
3135 safe_create_dir(sb
.buf
, 1);
3138 files_ref_path(refs
, &sb
, "refs/tags");
3139 safe_create_dir(sb
.buf
, 1);
3141 strbuf_release(&sb
);
3145 struct ref_storage_be refs_be_files
= {
3148 files_ref_store_create
,
3150 files_transaction_prepare
,
3151 files_transaction_finish
,
3152 files_transaction_abort
,
3153 files_initial_transaction_commit
,
3156 files_create_symref
,
3161 files_ref_iterator_begin
,
3164 files_reflog_iterator_begin
,
3165 files_for_each_reflog_ent
,
3166 files_for_each_reflog_ent_reverse
,
3167 files_reflog_exists
,
3168 files_create_reflog
,
3169 files_delete_reflog
,