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"
15 * This backend uses the following flags in `ref_update::flags` for
16 * internal bookkeeping purposes. Their numerical values must not
17 * conflict with REF_NO_DEREF, REF_FORCE_CREATE_REFLOG, REF_HAVE_NEW,
18 * REF_HAVE_OLD, or REF_IS_PRUNING, which are also stored in
19 * `ref_update::flags`.
23 * Used as a flag in ref_update::flags when a loose ref is being
24 * pruned. This flag must only be used when REF_NO_DEREF is set.
26 #define REF_IS_PRUNING (1 << 4)
29 * Flag passed to lock_ref_sha1_basic() telling it to tolerate broken
30 * refs (i.e., because the reference is about to be deleted anyway).
32 #define REF_DELETING (1 << 5)
35 * Used as a flag in ref_update::flags when the lockfile needs to be
38 #define REF_NEEDS_COMMIT (1 << 6)
41 * Used as a flag in ref_update::flags when we want to log a ref
42 * update but not actually perform it. This is used when a symbolic
43 * ref update is split up.
45 #define REF_LOG_ONLY (1 << 7)
48 * Used as a flag in ref_update::flags when the ref_update was via an
51 #define REF_UPDATE_VIA_HEAD (1 << 8)
54 * Used as a flag in ref_update::flags when the loose reference has
57 #define REF_DELETED_LOOSE (1 << 9)
62 struct object_id old_oid
;
65 struct files_ref_store
{
66 struct ref_store base
;
67 unsigned int store_flags
;
72 struct ref_cache
*loose
;
74 struct ref_store
*packed_ref_store
;
77 static void clear_loose_ref_cache(struct files_ref_store
*refs
)
80 free_ref_cache(refs
->loose
);
86 * Create a new submodule ref cache and add it to the internal
89 static struct ref_store
*files_ref_store_create(const char *gitdir
,
92 struct files_ref_store
*refs
= xcalloc(1, sizeof(*refs
));
93 struct ref_store
*ref_store
= (struct ref_store
*)refs
;
94 struct strbuf sb
= STRBUF_INIT
;
96 base_ref_store_init(ref_store
, &refs_be_files
);
97 refs
->store_flags
= flags
;
99 refs
->gitdir
= xstrdup(gitdir
);
100 get_common_dir_noenv(&sb
, gitdir
);
101 refs
->gitcommondir
= strbuf_detach(&sb
, NULL
);
102 strbuf_addf(&sb
, "%s/packed-refs", refs
->gitcommondir
);
103 refs
->packed_ref_store
= packed_ref_store_create(sb
.buf
, flags
);
106 chdir_notify_reparent("files-backend $GIT_DIR",
108 chdir_notify_reparent("files-backend $GIT_COMMONDIR",
109 &refs
->gitcommondir
);
115 * Die if refs is not the main ref store. caller is used in any
116 * necessary error messages.
118 static void files_assert_main_repository(struct files_ref_store
*refs
,
121 if (refs
->store_flags
& REF_STORE_MAIN
)
124 BUG("operation %s only allowed for main ref store", caller
);
128 * Downcast ref_store to files_ref_store. Die if ref_store is not a
129 * files_ref_store. required_flags is compared with ref_store's
130 * store_flags to ensure the ref_store has all required capabilities.
131 * "caller" is used in any necessary error messages.
133 static struct files_ref_store
*files_downcast(struct ref_store
*ref_store
,
134 unsigned int required_flags
,
137 struct files_ref_store
*refs
;
139 if (ref_store
->be
!= &refs_be_files
)
140 BUG("ref_store is type \"%s\" not \"files\" in %s",
141 ref_store
->be
->name
, caller
);
143 refs
= (struct files_ref_store
*)ref_store
;
145 if ((refs
->store_flags
& required_flags
) != required_flags
)
146 BUG("operation %s requires abilities 0x%x, but only have 0x%x",
147 caller
, required_flags
, refs
->store_flags
);
152 static void files_reflog_path(struct files_ref_store
*refs
,
156 switch (ref_type(refname
)) {
157 case REF_TYPE_PER_WORKTREE
:
158 case REF_TYPE_PSEUDOREF
:
159 strbuf_addf(sb
, "%s/logs/%s", refs
->gitdir
, refname
);
161 case REF_TYPE_NORMAL
:
162 strbuf_addf(sb
, "%s/logs/%s", refs
->gitcommondir
, refname
);
165 BUG("unknown ref type %d of ref %s",
166 ref_type(refname
), refname
);
170 static void files_ref_path(struct files_ref_store
*refs
,
174 switch (ref_type(refname
)) {
175 case REF_TYPE_PER_WORKTREE
:
176 case REF_TYPE_PSEUDOREF
:
177 strbuf_addf(sb
, "%s/%s", refs
->gitdir
, refname
);
179 case REF_TYPE_NORMAL
:
180 strbuf_addf(sb
, "%s/%s", refs
->gitcommondir
, refname
);
183 BUG("unknown ref type %d of ref %s",
184 ref_type(refname
), refname
);
189 * Read the loose references from the namespace dirname into dir
190 * (without recursing). dirname must end with '/'. dir must be the
191 * directory entry corresponding to dirname.
193 static void loose_fill_ref_dir(struct ref_store
*ref_store
,
194 struct ref_dir
*dir
, const char *dirname
)
196 struct files_ref_store
*refs
=
197 files_downcast(ref_store
, REF_STORE_READ
, "fill_ref_dir");
200 int dirnamelen
= strlen(dirname
);
201 struct strbuf refname
;
202 struct strbuf path
= STRBUF_INIT
;
205 files_ref_path(refs
, &path
, dirname
);
206 path_baselen
= path
.len
;
208 d
= opendir(path
.buf
);
210 strbuf_release(&path
);
214 strbuf_init(&refname
, dirnamelen
+ 257);
215 strbuf_add(&refname
, dirname
, dirnamelen
);
217 while ((de
= readdir(d
)) != NULL
) {
218 struct object_id oid
;
222 if (de
->d_name
[0] == '.')
224 if (ends_with(de
->d_name
, ".lock"))
226 strbuf_addstr(&refname
, de
->d_name
);
227 strbuf_addstr(&path
, de
->d_name
);
228 if (stat(path
.buf
, &st
) < 0) {
229 ; /* silently ignore */
230 } else if (S_ISDIR(st
.st_mode
)) {
231 strbuf_addch(&refname
, '/');
232 add_entry_to_dir(dir
,
233 create_dir_entry(dir
->cache
, refname
.buf
,
236 if (!refs_resolve_ref_unsafe(&refs
->base
,
241 flag
|= REF_ISBROKEN
;
242 } else if (is_null_oid(&oid
)) {
244 * It is so astronomically unlikely
245 * that null_oid is the OID of an
246 * actual object that we consider its
247 * appearance in a loose reference
248 * file to be repo corruption
249 * (probably due to a software bug).
251 flag
|= REF_ISBROKEN
;
254 if (check_refname_format(refname
.buf
,
255 REFNAME_ALLOW_ONELEVEL
)) {
256 if (!refname_is_safe(refname
.buf
))
257 die("loose refname is dangerous: %s", refname
.buf
);
259 flag
|= REF_BAD_NAME
| REF_ISBROKEN
;
261 add_entry_to_dir(dir
,
262 create_ref_entry(refname
.buf
, &oid
, flag
));
264 strbuf_setlen(&refname
, dirnamelen
);
265 strbuf_setlen(&path
, path_baselen
);
267 strbuf_release(&refname
);
268 strbuf_release(&path
);
272 * Manually add refs/bisect, which, being per-worktree, might
273 * not appear in the directory listing for refs/ in the main
276 if (!strcmp(dirname
, "refs/")) {
277 int pos
= search_ref_dir(dir
, "refs/bisect/", 12);
280 struct ref_entry
*child_entry
= create_dir_entry(
281 dir
->cache
, "refs/bisect/", 12, 1);
282 add_entry_to_dir(dir
, child_entry
);
287 static struct ref_cache
*get_loose_ref_cache(struct files_ref_store
*refs
)
291 * Mark the top-level directory complete because we
292 * are about to read the only subdirectory that can
295 refs
->loose
= create_ref_cache(&refs
->base
, loose_fill_ref_dir
);
297 /* We're going to fill the top level ourselves: */
298 refs
->loose
->root
->flag
&= ~REF_INCOMPLETE
;
301 * Add an incomplete entry for "refs/" (to be filled
304 add_entry_to_dir(get_ref_dir(refs
->loose
->root
),
305 create_dir_entry(refs
->loose
, "refs/", 5, 1));
310 static int files_read_raw_ref(struct ref_store
*ref_store
,
311 const char *refname
, struct object_id
*oid
,
312 struct strbuf
*referent
, unsigned int *type
)
314 struct files_ref_store
*refs
=
315 files_downcast(ref_store
, REF_STORE_READ
, "read_raw_ref");
316 struct strbuf sb_contents
= STRBUF_INIT
;
317 struct strbuf sb_path
= STRBUF_INIT
;
325 int remaining_retries
= 3;
328 strbuf_reset(&sb_path
);
330 files_ref_path(refs
, &sb_path
, refname
);
336 * We might have to loop back here to avoid a race
337 * condition: first we lstat() the file, then we try
338 * to read it as a link or as a file. But if somebody
339 * changes the type of the file (file <-> directory
340 * <-> symlink) between the lstat() and reading, then
341 * we don't want to report that as an error but rather
342 * try again starting with the lstat().
344 * We'll keep a count of the retries, though, just to avoid
345 * any confusing situation sending us into an infinite loop.
348 if (remaining_retries
-- <= 0)
351 if (lstat(path
, &st
) < 0) {
354 if (refs_read_raw_ref(refs
->packed_ref_store
, refname
,
355 oid
, referent
, type
)) {
363 /* Follow "normalized" - ie "refs/.." symlinks by hand */
364 if (S_ISLNK(st
.st_mode
)) {
365 strbuf_reset(&sb_contents
);
366 if (strbuf_readlink(&sb_contents
, path
, st
.st_size
) < 0) {
367 if (errno
== ENOENT
|| errno
== EINVAL
)
368 /* inconsistent with lstat; retry */
373 if (starts_with(sb_contents
.buf
, "refs/") &&
374 !check_refname_format(sb_contents
.buf
, 0)) {
375 strbuf_swap(&sb_contents
, referent
);
376 *type
|= REF_ISSYMREF
;
381 * It doesn't look like a refname; fall through to just
382 * treating it like a non-symlink, and reading whatever it
387 /* Is it a directory? */
388 if (S_ISDIR(st
.st_mode
)) {
390 * Even though there is a directory where the loose
391 * ref is supposed to be, there could still be a
394 if (refs_read_raw_ref(refs
->packed_ref_store
, refname
,
395 oid
, referent
, type
)) {
404 * Anything else, just open it and try to use it as
407 fd
= open(path
, O_RDONLY
);
409 if (errno
== ENOENT
&& !S_ISLNK(st
.st_mode
))
410 /* inconsistent with lstat; retry */
415 strbuf_reset(&sb_contents
);
416 if (strbuf_read(&sb_contents
, fd
, 256) < 0) {
417 int save_errno
= errno
;
423 strbuf_rtrim(&sb_contents
);
424 buf
= sb_contents
.buf
;
425 if (starts_with(buf
, "ref:")) {
427 while (isspace(*buf
))
430 strbuf_reset(referent
);
431 strbuf_addstr(referent
, buf
);
432 *type
|= REF_ISSYMREF
;
438 * Please note that FETCH_HEAD has additional
439 * data after the sha.
441 if (parse_oid_hex(buf
, oid
, &p
) ||
442 (*p
!= '\0' && !isspace(*p
))) {
443 *type
|= REF_ISBROKEN
;
452 strbuf_release(&sb_path
);
453 strbuf_release(&sb_contents
);
458 static void unlock_ref(struct ref_lock
*lock
)
460 rollback_lock_file(&lock
->lk
);
461 free(lock
->ref_name
);
466 * Lock refname, without following symrefs, and set *lock_p to point
467 * at a newly-allocated lock object. Fill in lock->old_oid, referent,
468 * and type similarly to read_raw_ref().
470 * The caller must verify that refname is a "safe" reference name (in
471 * the sense of refname_is_safe()) before calling this function.
473 * If the reference doesn't already exist, verify that refname doesn't
474 * have a D/F conflict with any existing references. extras and skip
475 * are passed to refs_verify_refname_available() for this check.
477 * If mustexist is not set and the reference is not found or is
478 * broken, lock the reference anyway but clear old_oid.
480 * Return 0 on success. On failure, write an error message to err and
481 * return TRANSACTION_NAME_CONFLICT or TRANSACTION_GENERIC_ERROR.
483 * Implementation note: This function is basically
488 * but it includes a lot more code to
489 * - Deal with possible races with other processes
490 * - Avoid calling refs_verify_refname_available() when it can be
491 * avoided, namely if we were successfully able to read the ref
492 * - Generate informative error messages in the case of failure
494 static int lock_raw_ref(struct files_ref_store
*refs
,
495 const char *refname
, int mustexist
,
496 const struct string_list
*extras
,
497 const struct string_list
*skip
,
498 struct ref_lock
**lock_p
,
499 struct strbuf
*referent
,
503 struct ref_lock
*lock
;
504 struct strbuf ref_file
= STRBUF_INIT
;
505 int attempts_remaining
= 3;
506 int ret
= TRANSACTION_GENERIC_ERROR
;
509 files_assert_main_repository(refs
, "lock_raw_ref");
513 /* First lock the file so it can't change out from under us. */
515 *lock_p
= lock
= xcalloc(1, sizeof(*lock
));
517 lock
->ref_name
= xstrdup(refname
);
518 files_ref_path(refs
, &ref_file
, refname
);
521 switch (safe_create_leading_directories(ref_file
.buf
)) {
526 * Suppose refname is "refs/foo/bar". We just failed
527 * to create the containing directory, "refs/foo",
528 * because there was a non-directory in the way. This
529 * indicates a D/F conflict, probably because of
530 * another reference such as "refs/foo". There is no
531 * reason to expect this error to be transitory.
533 if (refs_verify_refname_available(&refs
->base
, refname
,
534 extras
, skip
, err
)) {
537 * To the user the relevant error is
538 * that the "mustexist" reference is
542 strbuf_addf(err
, "unable to resolve reference '%s'",
546 * The error message set by
547 * refs_verify_refname_available() is
550 ret
= TRANSACTION_NAME_CONFLICT
;
554 * The file that is in the way isn't a loose
555 * reference. Report it as a low-level
558 strbuf_addf(err
, "unable to create lock file %s.lock; "
559 "non-directory in the way",
564 /* Maybe another process was tidying up. Try again. */
565 if (--attempts_remaining
> 0)
569 strbuf_addf(err
, "unable to create directory for %s",
574 if (hold_lock_file_for_update_timeout(
575 &lock
->lk
, ref_file
.buf
, LOCK_NO_DEREF
,
576 get_files_ref_lock_timeout_ms()) < 0) {
577 if (errno
== ENOENT
&& --attempts_remaining
> 0) {
579 * Maybe somebody just deleted one of the
580 * directories leading to ref_file. Try
585 unable_to_lock_message(ref_file
.buf
, errno
, err
);
591 * Now we hold the lock and can read the reference without
592 * fear that its value will change.
595 if (files_read_raw_ref(&refs
->base
, refname
,
596 &lock
->old_oid
, referent
, type
)) {
597 if (errno
== ENOENT
) {
599 /* Garden variety missing reference. */
600 strbuf_addf(err
, "unable to resolve reference '%s'",
605 * Reference is missing, but that's OK. We
606 * know that there is not a conflict with
607 * another loose reference because
608 * (supposing that we are trying to lock
609 * reference "refs/foo/bar"):
611 * - We were successfully able to create
612 * the lockfile refs/foo/bar.lock, so we
613 * know there cannot be a loose reference
616 * - We got ENOENT and not EISDIR, so we
617 * know that there cannot be a loose
618 * reference named "refs/foo/bar/baz".
621 } else if (errno
== EISDIR
) {
623 * There is a directory in the way. It might have
624 * contained references that have been deleted. If
625 * we don't require that the reference already
626 * exists, try to remove the directory so that it
627 * doesn't cause trouble when we want to rename the
628 * lockfile into place later.
631 /* Garden variety missing reference. */
632 strbuf_addf(err
, "unable to resolve reference '%s'",
635 } else if (remove_dir_recursively(&ref_file
,
636 REMOVE_DIR_EMPTY_ONLY
)) {
637 if (refs_verify_refname_available(
638 &refs
->base
, refname
,
639 extras
, skip
, err
)) {
641 * The error message set by
642 * verify_refname_available() is OK.
644 ret
= TRANSACTION_NAME_CONFLICT
;
648 * We can't delete the directory,
649 * but we also don't know of any
650 * references that it should
653 strbuf_addf(err
, "there is a non-empty directory '%s' "
654 "blocking reference '%s'",
655 ref_file
.buf
, refname
);
659 } else if (errno
== EINVAL
&& (*type
& REF_ISBROKEN
)) {
660 strbuf_addf(err
, "unable to resolve reference '%s': "
661 "reference broken", refname
);
664 strbuf_addf(err
, "unable to resolve reference '%s': %s",
665 refname
, strerror(errno
));
670 * If the ref did not exist and we are creating it,
671 * make sure there is no existing packed ref that
672 * conflicts with refname:
674 if (refs_verify_refname_available(
675 refs
->packed_ref_store
, refname
,
688 strbuf_release(&ref_file
);
692 struct files_ref_iterator
{
693 struct ref_iterator base
;
695 struct ref_iterator
*iter0
;
699 static int files_ref_iterator_advance(struct ref_iterator
*ref_iterator
)
701 struct files_ref_iterator
*iter
=
702 (struct files_ref_iterator
*)ref_iterator
;
705 while ((ok
= ref_iterator_advance(iter
->iter0
)) == ITER_OK
) {
706 if (iter
->flags
& DO_FOR_EACH_PER_WORKTREE_ONLY
&&
707 ref_type(iter
->iter0
->refname
) != REF_TYPE_PER_WORKTREE
)
710 if (!(iter
->flags
& DO_FOR_EACH_INCLUDE_BROKEN
) &&
711 !ref_resolves_to_object(iter
->iter0
->refname
,
716 iter
->base
.refname
= iter
->iter0
->refname
;
717 iter
->base
.oid
= iter
->iter0
->oid
;
718 iter
->base
.flags
= iter
->iter0
->flags
;
723 if (ref_iterator_abort(ref_iterator
) != ITER_DONE
)
729 static int files_ref_iterator_peel(struct ref_iterator
*ref_iterator
,
730 struct object_id
*peeled
)
732 struct files_ref_iterator
*iter
=
733 (struct files_ref_iterator
*)ref_iterator
;
735 return ref_iterator_peel(iter
->iter0
, peeled
);
738 static int files_ref_iterator_abort(struct ref_iterator
*ref_iterator
)
740 struct files_ref_iterator
*iter
=
741 (struct files_ref_iterator
*)ref_iterator
;
745 ok
= ref_iterator_abort(iter
->iter0
);
747 base_ref_iterator_free(ref_iterator
);
751 static struct ref_iterator_vtable files_ref_iterator_vtable
= {
752 files_ref_iterator_advance
,
753 files_ref_iterator_peel
,
754 files_ref_iterator_abort
757 static struct ref_iterator
*files_ref_iterator_begin(
758 struct ref_store
*ref_store
,
759 const char *prefix
, unsigned int flags
)
761 struct files_ref_store
*refs
;
762 struct ref_iterator
*loose_iter
, *packed_iter
, *overlay_iter
;
763 struct files_ref_iterator
*iter
;
764 struct ref_iterator
*ref_iterator
;
765 unsigned int required_flags
= REF_STORE_READ
;
767 if (!(flags
& DO_FOR_EACH_INCLUDE_BROKEN
))
768 required_flags
|= REF_STORE_ODB
;
770 refs
= files_downcast(ref_store
, required_flags
, "ref_iterator_begin");
773 * We must make sure that all loose refs are read before
774 * accessing the packed-refs file; this avoids a race
775 * condition if loose refs are migrated to the packed-refs
776 * file by a simultaneous process, but our in-memory view is
777 * from before the migration. We ensure this as follows:
778 * First, we call start the loose refs iteration with its
779 * `prime_ref` argument set to true. This causes the loose
780 * references in the subtree to be pre-read into the cache.
781 * (If they've already been read, that's OK; we only need to
782 * guarantee that they're read before the packed refs, not
783 * *how much* before.) After that, we call
784 * packed_ref_iterator_begin(), which internally checks
785 * whether the packed-ref cache is up to date with what is on
786 * disk, and re-reads it if not.
789 loose_iter
= cache_ref_iterator_begin(get_loose_ref_cache(refs
),
793 * The packed-refs file might contain broken references, for
794 * example an old version of a reference that points at an
795 * object that has since been garbage-collected. This is OK as
796 * long as there is a corresponding loose reference that
797 * overrides it, and we don't want to emit an error message in
798 * this case. So ask the packed_ref_store for all of its
799 * references, and (if needed) do our own check for broken
800 * ones in files_ref_iterator_advance(), after we have merged
801 * the packed and loose references.
803 packed_iter
= refs_ref_iterator_begin(
804 refs
->packed_ref_store
, prefix
, 0,
805 DO_FOR_EACH_INCLUDE_BROKEN
);
807 overlay_iter
= overlay_ref_iterator_begin(loose_iter
, packed_iter
);
809 iter
= xcalloc(1, sizeof(*iter
));
810 ref_iterator
= &iter
->base
;
811 base_ref_iterator_init(ref_iterator
, &files_ref_iterator_vtable
,
812 overlay_iter
->ordered
);
813 iter
->iter0
= overlay_iter
;
820 * Verify that the reference locked by lock has the value old_oid
821 * (unless it is NULL). Fail if the reference doesn't exist and
822 * mustexist is set. Return 0 on success. On error, write an error
823 * message to err, set errno, and return a negative value.
825 static int verify_lock(struct ref_store
*ref_store
, struct ref_lock
*lock
,
826 const struct object_id
*old_oid
, int mustexist
,
831 if (refs_read_ref_full(ref_store
, lock
->ref_name
,
832 mustexist
? RESOLVE_REF_READING
: 0,
833 &lock
->old_oid
, NULL
)) {
835 int save_errno
= errno
;
836 strbuf_addf(err
, "can't verify ref '%s'", lock
->ref_name
);
840 oidclr(&lock
->old_oid
);
844 if (old_oid
&& oidcmp(&lock
->old_oid
, old_oid
)) {
845 strbuf_addf(err
, "ref '%s' is at %s but expected %s",
847 oid_to_hex(&lock
->old_oid
),
848 oid_to_hex(old_oid
));
855 static int remove_empty_directories(struct strbuf
*path
)
858 * we want to create a file but there is a directory there;
859 * if that is an empty directory (or a directory that contains
860 * only empty directories), remove them.
862 return remove_dir_recursively(path
, REMOVE_DIR_EMPTY_ONLY
);
865 static int create_reflock(const char *path
, void *cb
)
867 struct lock_file
*lk
= cb
;
869 return hold_lock_file_for_update_timeout(
870 lk
, path
, LOCK_NO_DEREF
,
871 get_files_ref_lock_timeout_ms()) < 0 ? -1 : 0;
875 * Locks a ref returning the lock on success and NULL on failure.
876 * On failure errno is set to something meaningful.
878 static struct ref_lock
*lock_ref_oid_basic(struct files_ref_store
*refs
,
880 const struct object_id
*old_oid
,
881 const struct string_list
*extras
,
882 const struct string_list
*skip
,
883 unsigned int flags
, int *type
,
886 struct strbuf ref_file
= STRBUF_INIT
;
887 struct ref_lock
*lock
;
889 int mustexist
= (old_oid
&& !is_null_oid(old_oid
));
890 int resolve_flags
= RESOLVE_REF_NO_RECURSE
;
893 files_assert_main_repository(refs
, "lock_ref_oid_basic");
896 lock
= xcalloc(1, sizeof(struct ref_lock
));
899 resolve_flags
|= RESOLVE_REF_READING
;
900 if (flags
& REF_DELETING
)
901 resolve_flags
|= RESOLVE_REF_ALLOW_BAD_NAME
;
903 files_ref_path(refs
, &ref_file
, refname
);
904 resolved
= !!refs_resolve_ref_unsafe(&refs
->base
,
905 refname
, resolve_flags
,
906 &lock
->old_oid
, type
);
907 if (!resolved
&& errno
== EISDIR
) {
909 * we are trying to lock foo but we used to
910 * have foo/bar which now does not exist;
911 * it is normal for the empty directory 'foo'
914 if (remove_empty_directories(&ref_file
)) {
916 if (!refs_verify_refname_available(
918 refname
, extras
, skip
, err
))
919 strbuf_addf(err
, "there are still refs under '%s'",
923 resolved
= !!refs_resolve_ref_unsafe(&refs
->base
,
924 refname
, resolve_flags
,
925 &lock
->old_oid
, type
);
929 if (last_errno
!= ENOTDIR
||
930 !refs_verify_refname_available(&refs
->base
, refname
,
932 strbuf_addf(err
, "unable to resolve reference '%s': %s",
933 refname
, strerror(last_errno
));
939 * If the ref did not exist and we are creating it, make sure
940 * there is no existing packed ref whose name begins with our
941 * refname, nor a packed ref whose name is a proper prefix of
944 if (is_null_oid(&lock
->old_oid
) &&
945 refs_verify_refname_available(refs
->packed_ref_store
, refname
,
946 extras
, skip
, err
)) {
947 last_errno
= ENOTDIR
;
951 lock
->ref_name
= xstrdup(refname
);
953 if (raceproof_create_file(ref_file
.buf
, create_reflock
, &lock
->lk
)) {
955 unable_to_lock_message(ref_file
.buf
, errno
, err
);
959 if (verify_lock(&refs
->base
, lock
, old_oid
, mustexist
, err
)) {
970 strbuf_release(&ref_file
);
975 struct ref_to_prune
{
976 struct ref_to_prune
*next
;
977 struct object_id oid
;
978 char name
[FLEX_ARRAY
];
982 REMOVE_EMPTY_PARENTS_REF
= 0x01,
983 REMOVE_EMPTY_PARENTS_REFLOG
= 0x02
987 * Remove empty parent directories associated with the specified
988 * reference and/or its reflog, but spare [logs/]refs/ and immediate
989 * subdirs. flags is a combination of REMOVE_EMPTY_PARENTS_REF and/or
990 * REMOVE_EMPTY_PARENTS_REFLOG.
992 static void try_remove_empty_parents(struct files_ref_store
*refs
,
996 struct strbuf buf
= STRBUF_INIT
;
997 struct strbuf sb
= STRBUF_INIT
;
1001 strbuf_addstr(&buf
, refname
);
1003 for (i
= 0; i
< 2; i
++) { /* refs/{heads,tags,...}/ */
1004 while (*p
&& *p
!= '/')
1006 /* tolerate duplicate slashes; see check_refname_format() */
1010 q
= buf
.buf
+ buf
.len
;
1011 while (flags
& (REMOVE_EMPTY_PARENTS_REF
| REMOVE_EMPTY_PARENTS_REFLOG
)) {
1012 while (q
> p
&& *q
!= '/')
1014 while (q
> p
&& *(q
-1) == '/')
1018 strbuf_setlen(&buf
, q
- buf
.buf
);
1021 files_ref_path(refs
, &sb
, buf
.buf
);
1022 if ((flags
& REMOVE_EMPTY_PARENTS_REF
) && rmdir(sb
.buf
))
1023 flags
&= ~REMOVE_EMPTY_PARENTS_REF
;
1026 files_reflog_path(refs
, &sb
, buf
.buf
);
1027 if ((flags
& REMOVE_EMPTY_PARENTS_REFLOG
) && rmdir(sb
.buf
))
1028 flags
&= ~REMOVE_EMPTY_PARENTS_REFLOG
;
1030 strbuf_release(&buf
);
1031 strbuf_release(&sb
);
1034 /* make sure nobody touched the ref, and unlink */
1035 static void prune_ref(struct files_ref_store
*refs
, struct ref_to_prune
*r
)
1037 struct ref_transaction
*transaction
;
1038 struct strbuf err
= STRBUF_INIT
;
1041 if (check_refname_format(r
->name
, 0))
1044 transaction
= ref_store_transaction_begin(&refs
->base
, &err
);
1047 ref_transaction_add_update(
1048 transaction
, r
->name
,
1049 REF_NO_DEREF
| REF_HAVE_NEW
| REF_HAVE_OLD
| REF_IS_PRUNING
,
1050 &null_oid
, &r
->oid
, NULL
);
1051 if (ref_transaction_commit(transaction
, &err
))
1058 error("%s", err
.buf
);
1059 strbuf_release(&err
);
1060 ref_transaction_free(transaction
);
1065 * Prune the loose versions of the references in the linked list
1066 * `*refs_to_prune`, freeing the entries in the list as we go.
1068 static void prune_refs(struct files_ref_store
*refs
, struct ref_to_prune
**refs_to_prune
)
1070 while (*refs_to_prune
) {
1071 struct ref_to_prune
*r
= *refs_to_prune
;
1072 *refs_to_prune
= r
->next
;
1079 * Return true if the specified reference should be packed.
1081 static int should_pack_ref(const char *refname
,
1082 const struct object_id
*oid
, unsigned int ref_flags
,
1083 unsigned int pack_flags
)
1085 /* Do not pack per-worktree refs: */
1086 if (ref_type(refname
) != REF_TYPE_NORMAL
)
1089 /* Do not pack non-tags unless PACK_REFS_ALL is set: */
1090 if (!(pack_flags
& PACK_REFS_ALL
) && !starts_with(refname
, "refs/tags/"))
1093 /* Do not pack symbolic refs: */
1094 if (ref_flags
& REF_ISSYMREF
)
1097 /* Do not pack broken refs: */
1098 if (!ref_resolves_to_object(refname
, oid
, ref_flags
))
1104 static int files_pack_refs(struct ref_store
*ref_store
, unsigned int flags
)
1106 struct files_ref_store
*refs
=
1107 files_downcast(ref_store
, REF_STORE_WRITE
| REF_STORE_ODB
,
1109 struct ref_iterator
*iter
;
1111 struct ref_to_prune
*refs_to_prune
= NULL
;
1112 struct strbuf err
= STRBUF_INIT
;
1113 struct ref_transaction
*transaction
;
1115 transaction
= ref_store_transaction_begin(refs
->packed_ref_store
, &err
);
1119 packed_refs_lock(refs
->packed_ref_store
, LOCK_DIE_ON_ERROR
, &err
);
1121 iter
= cache_ref_iterator_begin(get_loose_ref_cache(refs
), NULL
, 0);
1122 while ((ok
= ref_iterator_advance(iter
)) == ITER_OK
) {
1124 * If the loose reference can be packed, add an entry
1125 * in the packed ref cache. If the reference should be
1126 * pruned, also add it to refs_to_prune.
1128 if (!should_pack_ref(iter
->refname
, iter
->oid
, iter
->flags
,
1133 * Add a reference creation for this reference to the
1134 * packed-refs transaction:
1136 if (ref_transaction_update(transaction
, iter
->refname
,
1138 REF_NO_DEREF
, NULL
, &err
))
1139 die("failure preparing to create packed reference %s: %s",
1140 iter
->refname
, err
.buf
);
1142 /* Schedule the loose reference for pruning if requested. */
1143 if ((flags
& PACK_REFS_PRUNE
)) {
1144 struct ref_to_prune
*n
;
1145 FLEX_ALLOC_STR(n
, name
, iter
->refname
);
1146 oidcpy(&n
->oid
, iter
->oid
);
1147 n
->next
= refs_to_prune
;
1151 if (ok
!= ITER_DONE
)
1152 die("error while iterating over references");
1154 if (ref_transaction_commit(transaction
, &err
))
1155 die("unable to write new packed-refs: %s", err
.buf
);
1157 ref_transaction_free(transaction
);
1159 packed_refs_unlock(refs
->packed_ref_store
);
1161 prune_refs(refs
, &refs_to_prune
);
1162 strbuf_release(&err
);
1166 static int files_delete_refs(struct ref_store
*ref_store
, const char *msg
,
1167 struct string_list
*refnames
, unsigned int flags
)
1169 struct files_ref_store
*refs
=
1170 files_downcast(ref_store
, REF_STORE_WRITE
, "delete_refs");
1171 struct strbuf err
= STRBUF_INIT
;
1177 if (packed_refs_lock(refs
->packed_ref_store
, 0, &err
))
1180 if (refs_delete_refs(refs
->packed_ref_store
, msg
, refnames
, flags
)) {
1181 packed_refs_unlock(refs
->packed_ref_store
);
1185 packed_refs_unlock(refs
->packed_ref_store
);
1187 for (i
= 0; i
< refnames
->nr
; i
++) {
1188 const char *refname
= refnames
->items
[i
].string
;
1190 if (refs_delete_ref(&refs
->base
, msg
, refname
, NULL
, flags
))
1191 result
|= error(_("could not remove reference %s"), refname
);
1194 strbuf_release(&err
);
1199 * If we failed to rewrite the packed-refs file, then it is
1200 * unsafe to try to remove loose refs, because doing so might
1201 * expose an obsolete packed value for a reference that might
1202 * even point at an object that has been garbage collected.
1204 if (refnames
->nr
== 1)
1205 error(_("could not delete reference %s: %s"),
1206 refnames
->items
[0].string
, err
.buf
);
1208 error(_("could not delete references: %s"), err
.buf
);
1210 strbuf_release(&err
);
1215 * People using contrib's git-new-workdir have .git/logs/refs ->
1216 * /some/other/path/.git/logs/refs, and that may live on another device.
1218 * IOW, to avoid cross device rename errors, the temporary renamed log must
1219 * live into logs/refs.
1221 #define TMP_RENAMED_LOG "refs/.tmp-renamed-log"
1224 const char *tmp_renamed_log
;
1228 static int rename_tmp_log_callback(const char *path
, void *cb_data
)
1230 struct rename_cb
*cb
= cb_data
;
1232 if (rename(cb
->tmp_renamed_log
, path
)) {
1234 * rename(a, b) when b is an existing directory ought
1235 * to result in ISDIR, but Solaris 5.8 gives ENOTDIR.
1236 * Sheesh. Record the true errno for error reporting,
1237 * but report EISDIR to raceproof_create_file() so
1238 * that it knows to retry.
1240 cb
->true_errno
= errno
;
1241 if (errno
== ENOTDIR
)
1249 static int rename_tmp_log(struct files_ref_store
*refs
, const char *newrefname
)
1251 struct strbuf path
= STRBUF_INIT
;
1252 struct strbuf tmp
= STRBUF_INIT
;
1253 struct rename_cb cb
;
1256 files_reflog_path(refs
, &path
, newrefname
);
1257 files_reflog_path(refs
, &tmp
, TMP_RENAMED_LOG
);
1258 cb
.tmp_renamed_log
= tmp
.buf
;
1259 ret
= raceproof_create_file(path
.buf
, rename_tmp_log_callback
, &cb
);
1261 if (errno
== EISDIR
)
1262 error("directory not empty: %s", path
.buf
);
1264 error("unable to move logfile %s to %s: %s",
1266 strerror(cb
.true_errno
));
1269 strbuf_release(&path
);
1270 strbuf_release(&tmp
);
1274 static int write_ref_to_lockfile(struct ref_lock
*lock
,
1275 const struct object_id
*oid
, struct strbuf
*err
);
1276 static int commit_ref_update(struct files_ref_store
*refs
,
1277 struct ref_lock
*lock
,
1278 const struct object_id
*oid
, const char *logmsg
,
1279 struct strbuf
*err
);
1281 static int files_copy_or_rename_ref(struct ref_store
*ref_store
,
1282 const char *oldrefname
, const char *newrefname
,
1283 const char *logmsg
, int copy
)
1285 struct files_ref_store
*refs
=
1286 files_downcast(ref_store
, REF_STORE_WRITE
, "rename_ref");
1287 struct object_id oid
, orig_oid
;
1288 int flag
= 0, logmoved
= 0;
1289 struct ref_lock
*lock
;
1290 struct stat loginfo
;
1291 struct strbuf sb_oldref
= STRBUF_INIT
;
1292 struct strbuf sb_newref
= STRBUF_INIT
;
1293 struct strbuf tmp_renamed_log
= STRBUF_INIT
;
1295 struct strbuf err
= STRBUF_INIT
;
1297 files_reflog_path(refs
, &sb_oldref
, oldrefname
);
1298 files_reflog_path(refs
, &sb_newref
, newrefname
);
1299 files_reflog_path(refs
, &tmp_renamed_log
, TMP_RENAMED_LOG
);
1301 log
= !lstat(sb_oldref
.buf
, &loginfo
);
1302 if (log
&& S_ISLNK(loginfo
.st_mode
)) {
1303 ret
= error("reflog for %s is a symlink", oldrefname
);
1307 if (!refs_resolve_ref_unsafe(&refs
->base
, oldrefname
,
1308 RESOLVE_REF_READING
| RESOLVE_REF_NO_RECURSE
,
1309 &orig_oid
, &flag
)) {
1310 ret
= error("refname %s not found", oldrefname
);
1314 if (flag
& REF_ISSYMREF
) {
1316 ret
= error("refname %s is a symbolic ref, copying it is not supported",
1319 ret
= error("refname %s is a symbolic ref, renaming it is not supported",
1323 if (!refs_rename_ref_available(&refs
->base
, oldrefname
, newrefname
)) {
1328 if (!copy
&& log
&& rename(sb_oldref
.buf
, tmp_renamed_log
.buf
)) {
1329 ret
= error("unable to move logfile logs/%s to logs/"TMP_RENAMED_LOG
": %s",
1330 oldrefname
, strerror(errno
));
1334 if (copy
&& log
&& copy_file(tmp_renamed_log
.buf
, sb_oldref
.buf
, 0644)) {
1335 ret
= error("unable to copy logfile logs/%s to logs/"TMP_RENAMED_LOG
": %s",
1336 oldrefname
, strerror(errno
));
1340 if (!copy
&& refs_delete_ref(&refs
->base
, logmsg
, oldrefname
,
1341 &orig_oid
, REF_NO_DEREF
)) {
1342 error("unable to delete old %s", oldrefname
);
1347 * Since we are doing a shallow lookup, oid is not the
1348 * correct value to pass to delete_ref as old_oid. But that
1349 * doesn't matter, because an old_oid check wouldn't add to
1350 * the safety anyway; we want to delete the reference whatever
1351 * its current value.
1353 if (!copy
&& !refs_read_ref_full(&refs
->base
, newrefname
,
1354 RESOLVE_REF_READING
| RESOLVE_REF_NO_RECURSE
,
1356 refs_delete_ref(&refs
->base
, NULL
, newrefname
,
1357 NULL
, REF_NO_DEREF
)) {
1358 if (errno
== EISDIR
) {
1359 struct strbuf path
= STRBUF_INIT
;
1362 files_ref_path(refs
, &path
, newrefname
);
1363 result
= remove_empty_directories(&path
);
1364 strbuf_release(&path
);
1367 error("Directory not empty: %s", newrefname
);
1371 error("unable to delete existing %s", newrefname
);
1376 if (log
&& rename_tmp_log(refs
, newrefname
))
1381 lock
= lock_ref_oid_basic(refs
, newrefname
, NULL
, NULL
, NULL
,
1382 REF_NO_DEREF
, NULL
, &err
);
1385 error("unable to copy '%s' to '%s': %s", oldrefname
, newrefname
, err
.buf
);
1387 error("unable to rename '%s' to '%s': %s", oldrefname
, newrefname
, err
.buf
);
1388 strbuf_release(&err
);
1391 oidcpy(&lock
->old_oid
, &orig_oid
);
1393 if (write_ref_to_lockfile(lock
, &orig_oid
, &err
) ||
1394 commit_ref_update(refs
, lock
, &orig_oid
, logmsg
, &err
)) {
1395 error("unable to write current sha1 into %s: %s", newrefname
, err
.buf
);
1396 strbuf_release(&err
);
1404 lock
= lock_ref_oid_basic(refs
, oldrefname
, NULL
, NULL
, NULL
,
1405 REF_NO_DEREF
, NULL
, &err
);
1407 error("unable to lock %s for rollback: %s", oldrefname
, err
.buf
);
1408 strbuf_release(&err
);
1412 flag
= log_all_ref_updates
;
1413 log_all_ref_updates
= LOG_REFS_NONE
;
1414 if (write_ref_to_lockfile(lock
, &orig_oid
, &err
) ||
1415 commit_ref_update(refs
, lock
, &orig_oid
, NULL
, &err
)) {
1416 error("unable to write current sha1 into %s: %s", oldrefname
, err
.buf
);
1417 strbuf_release(&err
);
1419 log_all_ref_updates
= flag
;
1422 if (logmoved
&& rename(sb_newref
.buf
, sb_oldref
.buf
))
1423 error("unable to restore logfile %s from %s: %s",
1424 oldrefname
, newrefname
, strerror(errno
));
1425 if (!logmoved
&& log
&&
1426 rename(tmp_renamed_log
.buf
, sb_oldref
.buf
))
1427 error("unable to restore logfile %s from logs/"TMP_RENAMED_LOG
": %s",
1428 oldrefname
, strerror(errno
));
1431 strbuf_release(&sb_newref
);
1432 strbuf_release(&sb_oldref
);
1433 strbuf_release(&tmp_renamed_log
);
1438 static int files_rename_ref(struct ref_store
*ref_store
,
1439 const char *oldrefname
, const char *newrefname
,
1442 return files_copy_or_rename_ref(ref_store
, oldrefname
,
1443 newrefname
, logmsg
, 0);
1446 static int files_copy_ref(struct ref_store
*ref_store
,
1447 const char *oldrefname
, const char *newrefname
,
1450 return files_copy_or_rename_ref(ref_store
, oldrefname
,
1451 newrefname
, logmsg
, 1);
1454 static int close_ref_gently(struct ref_lock
*lock
)
1456 if (close_lock_file_gently(&lock
->lk
))
1461 static int commit_ref(struct ref_lock
*lock
)
1463 char *path
= get_locked_file_path(&lock
->lk
);
1466 if (!lstat(path
, &st
) && S_ISDIR(st
.st_mode
)) {
1468 * There is a directory at the path we want to rename
1469 * the lockfile to. Hopefully it is empty; try to
1472 size_t len
= strlen(path
);
1473 struct strbuf sb_path
= STRBUF_INIT
;
1475 strbuf_attach(&sb_path
, path
, len
, len
);
1478 * If this fails, commit_lock_file() will also fail
1479 * and will report the problem.
1481 remove_empty_directories(&sb_path
);
1482 strbuf_release(&sb_path
);
1487 if (commit_lock_file(&lock
->lk
))
1492 static int open_or_create_logfile(const char *path
, void *cb
)
1496 *fd
= open(path
, O_APPEND
| O_WRONLY
| O_CREAT
, 0666);
1497 return (*fd
< 0) ? -1 : 0;
1501 * Create a reflog for a ref. If force_create = 0, only create the
1502 * reflog for certain refs (those for which should_autocreate_reflog
1503 * returns non-zero). Otherwise, create it regardless of the reference
1504 * name. If the logfile already existed or was created, return 0 and
1505 * set *logfd to the file descriptor opened for appending to the file.
1506 * If no logfile exists and we decided not to create one, return 0 and
1507 * set *logfd to -1. On failure, fill in *err, set *logfd to -1, and
1510 static int log_ref_setup(struct files_ref_store
*refs
,
1511 const char *refname
, int force_create
,
1512 int *logfd
, struct strbuf
*err
)
1514 struct strbuf logfile_sb
= STRBUF_INIT
;
1517 files_reflog_path(refs
, &logfile_sb
, refname
);
1518 logfile
= strbuf_detach(&logfile_sb
, NULL
);
1520 if (force_create
|| should_autocreate_reflog(refname
)) {
1521 if (raceproof_create_file(logfile
, open_or_create_logfile
, logfd
)) {
1522 if (errno
== ENOENT
)
1523 strbuf_addf(err
, "unable to create directory for '%s': "
1524 "%s", logfile
, strerror(errno
));
1525 else if (errno
== EISDIR
)
1526 strbuf_addf(err
, "there are still logs under '%s'",
1529 strbuf_addf(err
, "unable to append to '%s': %s",
1530 logfile
, strerror(errno
));
1535 *logfd
= open(logfile
, O_APPEND
| O_WRONLY
, 0666);
1537 if (errno
== ENOENT
|| errno
== EISDIR
) {
1539 * The logfile doesn't already exist,
1540 * but that is not an error; it only
1541 * means that we won't write log
1546 strbuf_addf(err
, "unable to append to '%s': %s",
1547 logfile
, strerror(errno
));
1554 adjust_shared_perm(logfile
);
1564 static int files_create_reflog(struct ref_store
*ref_store
,
1565 const char *refname
, int force_create
,
1568 struct files_ref_store
*refs
=
1569 files_downcast(ref_store
, REF_STORE_WRITE
, "create_reflog");
1572 if (log_ref_setup(refs
, refname
, force_create
, &fd
, err
))
1581 static int log_ref_write_fd(int fd
, const struct object_id
*old_oid
,
1582 const struct object_id
*new_oid
,
1583 const char *committer
, const char *msg
)
1585 struct strbuf sb
= STRBUF_INIT
;
1588 strbuf_addf(&sb
, "%s %s %s", oid_to_hex(old_oid
), oid_to_hex(new_oid
), committer
);
1590 copy_reflog_msg(&sb
, msg
);
1591 strbuf_addch(&sb
, '\n');
1592 if (write_in_full(fd
, sb
.buf
, sb
.len
) < 0)
1594 strbuf_release(&sb
);
1598 static int files_log_ref_write(struct files_ref_store
*refs
,
1599 const char *refname
, const struct object_id
*old_oid
,
1600 const struct object_id
*new_oid
, const char *msg
,
1601 int flags
, struct strbuf
*err
)
1605 if (log_all_ref_updates
== LOG_REFS_UNSET
)
1606 log_all_ref_updates
= is_bare_repository() ? LOG_REFS_NONE
: LOG_REFS_NORMAL
;
1608 result
= log_ref_setup(refs
, refname
,
1609 flags
& REF_FORCE_CREATE_REFLOG
,
1617 result
= log_ref_write_fd(logfd
, old_oid
, new_oid
,
1618 git_committer_info(0), msg
);
1620 struct strbuf sb
= STRBUF_INIT
;
1621 int save_errno
= errno
;
1623 files_reflog_path(refs
, &sb
, refname
);
1624 strbuf_addf(err
, "unable to append to '%s': %s",
1625 sb
.buf
, strerror(save_errno
));
1626 strbuf_release(&sb
);
1631 struct strbuf sb
= STRBUF_INIT
;
1632 int save_errno
= errno
;
1634 files_reflog_path(refs
, &sb
, refname
);
1635 strbuf_addf(err
, "unable to append to '%s': %s",
1636 sb
.buf
, strerror(save_errno
));
1637 strbuf_release(&sb
);
1644 * Write oid into the open lockfile, then close the lockfile. On
1645 * errors, rollback the lockfile, fill in *err and return -1.
1647 static int write_ref_to_lockfile(struct ref_lock
*lock
,
1648 const struct object_id
*oid
, struct strbuf
*err
)
1650 static char term
= '\n';
1654 o
= parse_object(the_repository
, oid
);
1657 "trying to write ref '%s' with nonexistent object %s",
1658 lock
->ref_name
, oid_to_hex(oid
));
1662 if (o
->type
!= OBJ_COMMIT
&& is_branch(lock
->ref_name
)) {
1664 "trying to write non-commit object %s to branch '%s'",
1665 oid_to_hex(oid
), lock
->ref_name
);
1669 fd
= get_lock_file_fd(&lock
->lk
);
1670 if (write_in_full(fd
, oid_to_hex(oid
), the_hash_algo
->hexsz
) < 0 ||
1671 write_in_full(fd
, &term
, 1) < 0 ||
1672 close_ref_gently(lock
) < 0) {
1674 "couldn't write '%s'", get_lock_file_path(&lock
->lk
));
1682 * Commit a change to a loose reference that has already been written
1683 * to the loose reference lockfile. Also update the reflogs if
1684 * necessary, using the specified lockmsg (which can be NULL).
1686 static int commit_ref_update(struct files_ref_store
*refs
,
1687 struct ref_lock
*lock
,
1688 const struct object_id
*oid
, const char *logmsg
,
1691 files_assert_main_repository(refs
, "commit_ref_update");
1693 clear_loose_ref_cache(refs
);
1694 if (files_log_ref_write(refs
, lock
->ref_name
,
1695 &lock
->old_oid
, oid
,
1697 char *old_msg
= strbuf_detach(err
, NULL
);
1698 strbuf_addf(err
, "cannot update the ref '%s': %s",
1699 lock
->ref_name
, old_msg
);
1705 if (strcmp(lock
->ref_name
, "HEAD") != 0) {
1707 * Special hack: If a branch is updated directly and HEAD
1708 * points to it (may happen on the remote side of a push
1709 * for example) then logically the HEAD reflog should be
1711 * A generic solution implies reverse symref information,
1712 * but finding all symrefs pointing to the given branch
1713 * would be rather costly for this rare event (the direct
1714 * update of a branch) to be worth it. So let's cheat and
1715 * check with HEAD only which should cover 99% of all usage
1716 * scenarios (even 100% of the default ones).
1719 const char *head_ref
;
1721 head_ref
= refs_resolve_ref_unsafe(&refs
->base
, "HEAD",
1722 RESOLVE_REF_READING
,
1724 if (head_ref
&& (head_flag
& REF_ISSYMREF
) &&
1725 !strcmp(head_ref
, lock
->ref_name
)) {
1726 struct strbuf log_err
= STRBUF_INIT
;
1727 if (files_log_ref_write(refs
, "HEAD",
1728 &lock
->old_oid
, oid
,
1729 logmsg
, 0, &log_err
)) {
1730 error("%s", log_err
.buf
);
1731 strbuf_release(&log_err
);
1736 if (commit_ref(lock
)) {
1737 strbuf_addf(err
, "couldn't set '%s'", lock
->ref_name
);
1746 static int create_ref_symlink(struct ref_lock
*lock
, const char *target
)
1749 #ifndef NO_SYMLINK_HEAD
1750 char *ref_path
= get_locked_file_path(&lock
->lk
);
1752 ret
= symlink(target
, ref_path
);
1756 fprintf(stderr
, "no symlink - falling back to symbolic ref\n");
1761 static void update_symref_reflog(struct files_ref_store
*refs
,
1762 struct ref_lock
*lock
, const char *refname
,
1763 const char *target
, const char *logmsg
)
1765 struct strbuf err
= STRBUF_INIT
;
1766 struct object_id new_oid
;
1768 !refs_read_ref_full(&refs
->base
, target
,
1769 RESOLVE_REF_READING
, &new_oid
, NULL
) &&
1770 files_log_ref_write(refs
, refname
, &lock
->old_oid
,
1771 &new_oid
, logmsg
, 0, &err
)) {
1772 error("%s", err
.buf
);
1773 strbuf_release(&err
);
1777 static int create_symref_locked(struct files_ref_store
*refs
,
1778 struct ref_lock
*lock
, const char *refname
,
1779 const char *target
, const char *logmsg
)
1781 if (prefer_symlink_refs
&& !create_ref_symlink(lock
, target
)) {
1782 update_symref_reflog(refs
, lock
, refname
, target
, logmsg
);
1786 if (!fdopen_lock_file(&lock
->lk
, "w"))
1787 return error("unable to fdopen %s: %s",
1788 lock
->lk
.tempfile
->filename
.buf
, strerror(errno
));
1790 update_symref_reflog(refs
, lock
, refname
, target
, logmsg
);
1792 /* no error check; commit_ref will check ferror */
1793 fprintf(lock
->lk
.tempfile
->fp
, "ref: %s\n", target
);
1794 if (commit_ref(lock
) < 0)
1795 return error("unable to write symref for %s: %s", refname
,
1800 static int files_create_symref(struct ref_store
*ref_store
,
1801 const char *refname
, const char *target
,
1804 struct files_ref_store
*refs
=
1805 files_downcast(ref_store
, REF_STORE_WRITE
, "create_symref");
1806 struct strbuf err
= STRBUF_INIT
;
1807 struct ref_lock
*lock
;
1810 lock
= lock_ref_oid_basic(refs
, refname
, NULL
,
1811 NULL
, NULL
, REF_NO_DEREF
, NULL
,
1814 error("%s", err
.buf
);
1815 strbuf_release(&err
);
1819 ret
= create_symref_locked(refs
, lock
, refname
, target
, logmsg
);
1824 static int files_reflog_exists(struct ref_store
*ref_store
,
1825 const char *refname
)
1827 struct files_ref_store
*refs
=
1828 files_downcast(ref_store
, REF_STORE_READ
, "reflog_exists");
1829 struct strbuf sb
= STRBUF_INIT
;
1833 files_reflog_path(refs
, &sb
, refname
);
1834 ret
= !lstat(sb
.buf
, &st
) && S_ISREG(st
.st_mode
);
1835 strbuf_release(&sb
);
1839 static int files_delete_reflog(struct ref_store
*ref_store
,
1840 const char *refname
)
1842 struct files_ref_store
*refs
=
1843 files_downcast(ref_store
, REF_STORE_WRITE
, "delete_reflog");
1844 struct strbuf sb
= STRBUF_INIT
;
1847 files_reflog_path(refs
, &sb
, refname
);
1848 ret
= remove_path(sb
.buf
);
1849 strbuf_release(&sb
);
1853 static int show_one_reflog_ent(struct strbuf
*sb
, each_reflog_ent_fn fn
, void *cb_data
)
1855 struct object_id ooid
, noid
;
1856 char *email_end
, *message
;
1857 timestamp_t timestamp
;
1859 const char *p
= sb
->buf
;
1861 /* old SP new SP name <email> SP time TAB msg LF */
1862 if (!sb
->len
|| sb
->buf
[sb
->len
- 1] != '\n' ||
1863 parse_oid_hex(p
, &ooid
, &p
) || *p
++ != ' ' ||
1864 parse_oid_hex(p
, &noid
, &p
) || *p
++ != ' ' ||
1865 !(email_end
= strchr(p
, '>')) ||
1866 email_end
[1] != ' ' ||
1867 !(timestamp
= parse_timestamp(email_end
+ 2, &message
, 10)) ||
1868 !message
|| message
[0] != ' ' ||
1869 (message
[1] != '+' && message
[1] != '-') ||
1870 !isdigit(message
[2]) || !isdigit(message
[3]) ||
1871 !isdigit(message
[4]) || !isdigit(message
[5]))
1872 return 0; /* corrupt? */
1873 email_end
[1] = '\0';
1874 tz
= strtol(message
+ 1, NULL
, 10);
1875 if (message
[6] != '\t')
1879 return fn(&ooid
, &noid
, p
, timestamp
, tz
, message
, cb_data
);
1882 static char *find_beginning_of_line(char *bob
, char *scan
)
1884 while (bob
< scan
&& *(--scan
) != '\n')
1885 ; /* keep scanning backwards */
1887 * Return either beginning of the buffer, or LF at the end of
1888 * the previous line.
1893 static int files_for_each_reflog_ent_reverse(struct ref_store
*ref_store
,
1894 const char *refname
,
1895 each_reflog_ent_fn fn
,
1898 struct files_ref_store
*refs
=
1899 files_downcast(ref_store
, REF_STORE_READ
,
1900 "for_each_reflog_ent_reverse");
1901 struct strbuf sb
= STRBUF_INIT
;
1904 int ret
= 0, at_tail
= 1;
1906 files_reflog_path(refs
, &sb
, refname
);
1907 logfp
= fopen(sb
.buf
, "r");
1908 strbuf_release(&sb
);
1912 /* Jump to the end */
1913 if (fseek(logfp
, 0, SEEK_END
) < 0)
1914 ret
= error("cannot seek back reflog for %s: %s",
1915 refname
, strerror(errno
));
1917 while (!ret
&& 0 < pos
) {
1923 /* Fill next block from the end */
1924 cnt
= (sizeof(buf
) < pos
) ? sizeof(buf
) : pos
;
1925 if (fseek(logfp
, pos
- cnt
, SEEK_SET
)) {
1926 ret
= error("cannot seek back reflog for %s: %s",
1927 refname
, strerror(errno
));
1930 nread
= fread(buf
, cnt
, 1, logfp
);
1932 ret
= error("cannot read %d bytes from reflog for %s: %s",
1933 cnt
, refname
, strerror(errno
));
1938 scanp
= endp
= buf
+ cnt
;
1939 if (at_tail
&& scanp
[-1] == '\n')
1940 /* Looking at the final LF at the end of the file */
1944 while (buf
< scanp
) {
1946 * terminating LF of the previous line, or the beginning
1951 bp
= find_beginning_of_line(buf
, scanp
);
1955 * The newline is the end of the previous line,
1956 * so we know we have complete line starting
1957 * at (bp + 1). Prefix it onto any prior data
1958 * we collected for the line and process it.
1960 strbuf_splice(&sb
, 0, 0, bp
+ 1, endp
- (bp
+ 1));
1963 ret
= show_one_reflog_ent(&sb
, fn
, cb_data
);
1969 * We are at the start of the buffer, and the
1970 * start of the file; there is no previous
1971 * line, and we have everything for this one.
1972 * Process it, and we can end the loop.
1974 strbuf_splice(&sb
, 0, 0, buf
, endp
- buf
);
1975 ret
= show_one_reflog_ent(&sb
, fn
, cb_data
);
1982 * We are at the start of the buffer, and there
1983 * is more file to read backwards. Which means
1984 * we are in the middle of a line. Note that we
1985 * may get here even if *bp was a newline; that
1986 * just means we are at the exact end of the
1987 * previous line, rather than some spot in the
1990 * Save away what we have to be combined with
1991 * the data from the next read.
1993 strbuf_splice(&sb
, 0, 0, buf
, endp
- buf
);
2000 BUG("reverse reflog parser had leftover data");
2003 strbuf_release(&sb
);
2007 static int files_for_each_reflog_ent(struct ref_store
*ref_store
,
2008 const char *refname
,
2009 each_reflog_ent_fn fn
, void *cb_data
)
2011 struct files_ref_store
*refs
=
2012 files_downcast(ref_store
, REF_STORE_READ
,
2013 "for_each_reflog_ent");
2015 struct strbuf sb
= STRBUF_INIT
;
2018 files_reflog_path(refs
, &sb
, refname
);
2019 logfp
= fopen(sb
.buf
, "r");
2020 strbuf_release(&sb
);
2024 while (!ret
&& !strbuf_getwholeline(&sb
, logfp
, '\n'))
2025 ret
= show_one_reflog_ent(&sb
, fn
, cb_data
);
2027 strbuf_release(&sb
);
2031 struct files_reflog_iterator
{
2032 struct ref_iterator base
;
2034 struct ref_store
*ref_store
;
2035 struct dir_iterator
*dir_iterator
;
2036 struct object_id oid
;
2039 static int files_reflog_iterator_advance(struct ref_iterator
*ref_iterator
)
2041 struct files_reflog_iterator
*iter
=
2042 (struct files_reflog_iterator
*)ref_iterator
;
2043 struct dir_iterator
*diter
= iter
->dir_iterator
;
2046 while ((ok
= dir_iterator_advance(diter
)) == ITER_OK
) {
2049 if (!S_ISREG(diter
->st
.st_mode
))
2051 if (diter
->basename
[0] == '.')
2053 if (ends_with(diter
->basename
, ".lock"))
2056 if (refs_read_ref_full(iter
->ref_store
,
2057 diter
->relative_path
, 0,
2058 &iter
->oid
, &flags
)) {
2059 error("bad ref for %s", diter
->path
.buf
);
2063 iter
->base
.refname
= diter
->relative_path
;
2064 iter
->base
.oid
= &iter
->oid
;
2065 iter
->base
.flags
= flags
;
2069 iter
->dir_iterator
= NULL
;
2070 if (ref_iterator_abort(ref_iterator
) == ITER_ERROR
)
2075 static int files_reflog_iterator_peel(struct ref_iterator
*ref_iterator
,
2076 struct object_id
*peeled
)
2078 BUG("ref_iterator_peel() called for reflog_iterator");
2081 static int files_reflog_iterator_abort(struct ref_iterator
*ref_iterator
)
2083 struct files_reflog_iterator
*iter
=
2084 (struct files_reflog_iterator
*)ref_iterator
;
2087 if (iter
->dir_iterator
)
2088 ok
= dir_iterator_abort(iter
->dir_iterator
);
2090 base_ref_iterator_free(ref_iterator
);
2094 static struct ref_iterator_vtable files_reflog_iterator_vtable
= {
2095 files_reflog_iterator_advance
,
2096 files_reflog_iterator_peel
,
2097 files_reflog_iterator_abort
2100 static struct ref_iterator
*reflog_iterator_begin(struct ref_store
*ref_store
,
2103 struct files_reflog_iterator
*iter
= xcalloc(1, sizeof(*iter
));
2104 struct ref_iterator
*ref_iterator
= &iter
->base
;
2105 struct strbuf sb
= STRBUF_INIT
;
2107 base_ref_iterator_init(ref_iterator
, &files_reflog_iterator_vtable
, 0);
2108 strbuf_addf(&sb
, "%s/logs", gitdir
);
2109 iter
->dir_iterator
= dir_iterator_begin(sb
.buf
);
2110 iter
->ref_store
= ref_store
;
2111 strbuf_release(&sb
);
2113 return ref_iterator
;
2116 static enum iterator_selection
reflog_iterator_select(
2117 struct ref_iterator
*iter_worktree
,
2118 struct ref_iterator
*iter_common
,
2121 if (iter_worktree
) {
2123 * We're a bit loose here. We probably should ignore
2124 * common refs if they are accidentally added as
2125 * per-worktree refs.
2127 return ITER_SELECT_0
;
2128 } else if (iter_common
) {
2129 if (ref_type(iter_common
->refname
) == REF_TYPE_NORMAL
)
2130 return ITER_SELECT_1
;
2133 * The main ref store may contain main worktree's
2134 * per-worktree refs, which should be ignored
2141 static struct ref_iterator
*files_reflog_iterator_begin(struct ref_store
*ref_store
)
2143 struct files_ref_store
*refs
=
2144 files_downcast(ref_store
, REF_STORE_READ
,
2145 "reflog_iterator_begin");
2147 if (!strcmp(refs
->gitdir
, refs
->gitcommondir
)) {
2148 return reflog_iterator_begin(ref_store
, refs
->gitcommondir
);
2150 return merge_ref_iterator_begin(
2152 reflog_iterator_begin(ref_store
, refs
->gitdir
),
2153 reflog_iterator_begin(ref_store
, refs
->gitcommondir
),
2154 reflog_iterator_select
, refs
);
2159 * If update is a direct update of head_ref (the reference pointed to
2160 * by HEAD), then add an extra REF_LOG_ONLY update for HEAD.
2162 static int split_head_update(struct ref_update
*update
,
2163 struct ref_transaction
*transaction
,
2164 const char *head_ref
,
2165 struct string_list
*affected_refnames
,
2168 struct string_list_item
*item
;
2169 struct ref_update
*new_update
;
2171 if ((update
->flags
& REF_LOG_ONLY
) ||
2172 (update
->flags
& REF_IS_PRUNING
) ||
2173 (update
->flags
& REF_UPDATE_VIA_HEAD
))
2176 if (strcmp(update
->refname
, head_ref
))
2180 * First make sure that HEAD is not already in the
2181 * transaction. This check is O(lg N) in the transaction
2182 * size, but it happens at most once per transaction.
2184 if (string_list_has_string(affected_refnames
, "HEAD")) {
2185 /* An entry already existed */
2187 "multiple updates for 'HEAD' (including one "
2188 "via its referent '%s') are not allowed",
2190 return TRANSACTION_NAME_CONFLICT
;
2193 new_update
= ref_transaction_add_update(
2194 transaction
, "HEAD",
2195 update
->flags
| REF_LOG_ONLY
| REF_NO_DEREF
,
2196 &update
->new_oid
, &update
->old_oid
,
2200 * Add "HEAD". This insertion is O(N) in the transaction
2201 * size, but it happens at most once per transaction.
2202 * Add new_update->refname instead of a literal "HEAD".
2204 if (strcmp(new_update
->refname
, "HEAD"))
2205 BUG("%s unexpectedly not 'HEAD'", new_update
->refname
);
2206 item
= string_list_insert(affected_refnames
, new_update
->refname
);
2207 item
->util
= new_update
;
2213 * update is for a symref that points at referent and doesn't have
2214 * REF_NO_DEREF set. Split it into two updates:
2215 * - The original update, but with REF_LOG_ONLY and REF_NO_DEREF set
2216 * - A new, separate update for the referent reference
2217 * Note that the new update will itself be subject to splitting when
2218 * the iteration gets to it.
2220 static int split_symref_update(struct files_ref_store
*refs
,
2221 struct ref_update
*update
,
2222 const char *referent
,
2223 struct ref_transaction
*transaction
,
2224 struct string_list
*affected_refnames
,
2227 struct string_list_item
*item
;
2228 struct ref_update
*new_update
;
2229 unsigned int new_flags
;
2232 * First make sure that referent is not already in the
2233 * transaction. This check is O(lg N) in the transaction
2234 * size, but it happens at most once per symref in a
2237 if (string_list_has_string(affected_refnames
, referent
)) {
2238 /* An entry already exists */
2240 "multiple updates for '%s' (including one "
2241 "via symref '%s') are not allowed",
2242 referent
, update
->refname
);
2243 return TRANSACTION_NAME_CONFLICT
;
2246 new_flags
= update
->flags
;
2247 if (!strcmp(update
->refname
, "HEAD")) {
2249 * Record that the new update came via HEAD, so that
2250 * when we process it, split_head_update() doesn't try
2251 * to add another reflog update for HEAD. Note that
2252 * this bit will be propagated if the new_update
2253 * itself needs to be split.
2255 new_flags
|= REF_UPDATE_VIA_HEAD
;
2258 new_update
= ref_transaction_add_update(
2259 transaction
, referent
, new_flags
,
2260 &update
->new_oid
, &update
->old_oid
,
2263 new_update
->parent_update
= update
;
2266 * Change the symbolic ref update to log only. Also, it
2267 * doesn't need to check its old OID value, as that will be
2268 * done when new_update is processed.
2270 update
->flags
|= REF_LOG_ONLY
| REF_NO_DEREF
;
2271 update
->flags
&= ~REF_HAVE_OLD
;
2274 * Add the referent. This insertion is O(N) in the transaction
2275 * size, but it happens at most once per symref in a
2276 * transaction. Make sure to add new_update->refname, which will
2277 * be valid as long as affected_refnames is in use, and NOT
2278 * referent, which might soon be freed by our caller.
2280 item
= string_list_insert(affected_refnames
, new_update
->refname
);
2282 BUG("%s unexpectedly found in affected_refnames",
2283 new_update
->refname
);
2284 item
->util
= new_update
;
2290 * Return the refname under which update was originally requested.
2292 static const char *original_update_refname(struct ref_update
*update
)
2294 while (update
->parent_update
)
2295 update
= update
->parent_update
;
2297 return update
->refname
;
2301 * Check whether the REF_HAVE_OLD and old_oid values stored in update
2302 * are consistent with oid, which is the reference's current value. If
2303 * everything is OK, return 0; otherwise, write an error message to
2304 * err and return -1.
2306 static int check_old_oid(struct ref_update
*update
, struct object_id
*oid
,
2309 if (!(update
->flags
& REF_HAVE_OLD
) ||
2310 !oidcmp(oid
, &update
->old_oid
))
2313 if (is_null_oid(&update
->old_oid
))
2314 strbuf_addf(err
, "cannot lock ref '%s': "
2315 "reference already exists",
2316 original_update_refname(update
));
2317 else if (is_null_oid(oid
))
2318 strbuf_addf(err
, "cannot lock ref '%s': "
2319 "reference is missing but expected %s",
2320 original_update_refname(update
),
2321 oid_to_hex(&update
->old_oid
));
2323 strbuf_addf(err
, "cannot lock ref '%s': "
2324 "is at %s but expected %s",
2325 original_update_refname(update
),
2327 oid_to_hex(&update
->old_oid
));
2333 * Prepare for carrying out update:
2334 * - Lock the reference referred to by update.
2335 * - Read the reference under lock.
2336 * - Check that its old OID value (if specified) is correct, and in
2337 * any case record it in update->lock->old_oid for later use when
2338 * writing the reflog.
2339 * - If it is a symref update without REF_NO_DEREF, split it up into a
2340 * REF_LOG_ONLY update of the symref and add a separate update for
2341 * the referent to transaction.
2342 * - If it is an update of head_ref, add a corresponding REF_LOG_ONLY
2345 static int lock_ref_for_update(struct files_ref_store
*refs
,
2346 struct ref_update
*update
,
2347 struct ref_transaction
*transaction
,
2348 const char *head_ref
,
2349 struct string_list
*affected_refnames
,
2352 struct strbuf referent
= STRBUF_INIT
;
2353 int mustexist
= (update
->flags
& REF_HAVE_OLD
) &&
2354 !is_null_oid(&update
->old_oid
);
2356 struct ref_lock
*lock
;
2358 files_assert_main_repository(refs
, "lock_ref_for_update");
2360 if ((update
->flags
& REF_HAVE_NEW
) && is_null_oid(&update
->new_oid
))
2361 update
->flags
|= REF_DELETING
;
2364 ret
= split_head_update(update
, transaction
, head_ref
,
2365 affected_refnames
, err
);
2370 ret
= lock_raw_ref(refs
, update
->refname
, mustexist
,
2371 affected_refnames
, NULL
,
2373 &update
->type
, err
);
2377 reason
= strbuf_detach(err
, NULL
);
2378 strbuf_addf(err
, "cannot lock ref '%s': %s",
2379 original_update_refname(update
), reason
);
2384 update
->backend_data
= lock
;
2386 if (update
->type
& REF_ISSYMREF
) {
2387 if (update
->flags
& REF_NO_DEREF
) {
2389 * We won't be reading the referent as part of
2390 * the transaction, so we have to read it here
2391 * to record and possibly check old_oid:
2393 if (refs_read_ref_full(&refs
->base
,
2395 &lock
->old_oid
, NULL
)) {
2396 if (update
->flags
& REF_HAVE_OLD
) {
2397 strbuf_addf(err
, "cannot lock ref '%s': "
2398 "error reading reference",
2399 original_update_refname(update
));
2400 ret
= TRANSACTION_GENERIC_ERROR
;
2403 } else if (check_old_oid(update
, &lock
->old_oid
, err
)) {
2404 ret
= TRANSACTION_GENERIC_ERROR
;
2409 * Create a new update for the reference this
2410 * symref is pointing at. Also, we will record
2411 * and verify old_oid for this update as part
2412 * of processing the split-off update, so we
2413 * don't have to do it here.
2415 ret
= split_symref_update(refs
, update
,
2416 referent
.buf
, transaction
,
2417 affected_refnames
, err
);
2422 struct ref_update
*parent_update
;
2424 if (check_old_oid(update
, &lock
->old_oid
, err
)) {
2425 ret
= TRANSACTION_GENERIC_ERROR
;
2430 * If this update is happening indirectly because of a
2431 * symref update, record the old OID in the parent
2434 for (parent_update
= update
->parent_update
;
2436 parent_update
= parent_update
->parent_update
) {
2437 struct ref_lock
*parent_lock
= parent_update
->backend_data
;
2438 oidcpy(&parent_lock
->old_oid
, &lock
->old_oid
);
2442 if ((update
->flags
& REF_HAVE_NEW
) &&
2443 !(update
->flags
& REF_DELETING
) &&
2444 !(update
->flags
& REF_LOG_ONLY
)) {
2445 if (!(update
->type
& REF_ISSYMREF
) &&
2446 !oidcmp(&lock
->old_oid
, &update
->new_oid
)) {
2448 * The reference already has the desired
2449 * value, so we don't need to write it.
2451 } else if (write_ref_to_lockfile(lock
, &update
->new_oid
,
2453 char *write_err
= strbuf_detach(err
, NULL
);
2456 * The lock was freed upon failure of
2457 * write_ref_to_lockfile():
2459 update
->backend_data
= NULL
;
2461 "cannot update ref '%s': %s",
2462 update
->refname
, write_err
);
2464 ret
= TRANSACTION_GENERIC_ERROR
;
2467 update
->flags
|= REF_NEEDS_COMMIT
;
2470 if (!(update
->flags
& REF_NEEDS_COMMIT
)) {
2472 * We didn't call write_ref_to_lockfile(), so
2473 * the lockfile is still open. Close it to
2474 * free up the file descriptor:
2476 if (close_ref_gently(lock
)) {
2477 strbuf_addf(err
, "couldn't close '%s.lock'",
2479 ret
= TRANSACTION_GENERIC_ERROR
;
2485 strbuf_release(&referent
);
2489 struct files_transaction_backend_data
{
2490 struct ref_transaction
*packed_transaction
;
2491 int packed_refs_locked
;
2495 * Unlock any references in `transaction` that are still locked, and
2496 * mark the transaction closed.
2498 static void files_transaction_cleanup(struct files_ref_store
*refs
,
2499 struct ref_transaction
*transaction
)
2502 struct files_transaction_backend_data
*backend_data
=
2503 transaction
->backend_data
;
2504 struct strbuf err
= STRBUF_INIT
;
2506 for (i
= 0; i
< transaction
->nr
; i
++) {
2507 struct ref_update
*update
= transaction
->updates
[i
];
2508 struct ref_lock
*lock
= update
->backend_data
;
2512 update
->backend_data
= NULL
;
2516 if (backend_data
->packed_transaction
&&
2517 ref_transaction_abort(backend_data
->packed_transaction
, &err
)) {
2518 error("error aborting transaction: %s", err
.buf
);
2519 strbuf_release(&err
);
2522 if (backend_data
->packed_refs_locked
)
2523 packed_refs_unlock(refs
->packed_ref_store
);
2527 transaction
->state
= REF_TRANSACTION_CLOSED
;
2530 static int files_transaction_prepare(struct ref_store
*ref_store
,
2531 struct ref_transaction
*transaction
,
2534 struct files_ref_store
*refs
=
2535 files_downcast(ref_store
, REF_STORE_WRITE
,
2536 "ref_transaction_prepare");
2539 struct string_list affected_refnames
= STRING_LIST_INIT_NODUP
;
2540 char *head_ref
= NULL
;
2542 struct files_transaction_backend_data
*backend_data
;
2543 struct ref_transaction
*packed_transaction
= NULL
;
2547 if (!transaction
->nr
)
2550 backend_data
= xcalloc(1, sizeof(*backend_data
));
2551 transaction
->backend_data
= backend_data
;
2554 * Fail if a refname appears more than once in the
2555 * transaction. (If we end up splitting up any updates using
2556 * split_symref_update() or split_head_update(), those
2557 * functions will check that the new updates don't have the
2558 * same refname as any existing ones.) Also fail if any of the
2559 * updates use REF_IS_PRUNING without REF_NO_DEREF.
2561 for (i
= 0; i
< transaction
->nr
; i
++) {
2562 struct ref_update
*update
= transaction
->updates
[i
];
2563 struct string_list_item
*item
=
2564 string_list_append(&affected_refnames
, update
->refname
);
2566 if ((update
->flags
& REF_IS_PRUNING
) &&
2567 !(update
->flags
& REF_NO_DEREF
))
2568 BUG("REF_IS_PRUNING set without REF_NO_DEREF");
2571 * We store a pointer to update in item->util, but at
2572 * the moment we never use the value of this field
2573 * except to check whether it is non-NULL.
2575 item
->util
= update
;
2577 string_list_sort(&affected_refnames
);
2578 if (ref_update_reject_duplicates(&affected_refnames
, err
)) {
2579 ret
= TRANSACTION_GENERIC_ERROR
;
2584 * Special hack: If a branch is updated directly and HEAD
2585 * points to it (may happen on the remote side of a push
2586 * for example) then logically the HEAD reflog should be
2589 * A generic solution would require reverse symref lookups,
2590 * but finding all symrefs pointing to a given branch would be
2591 * rather costly for this rare event (the direct update of a
2592 * branch) to be worth it. So let's cheat and check with HEAD
2593 * only, which should cover 99% of all usage scenarios (even
2594 * 100% of the default ones).
2596 * So if HEAD is a symbolic reference, then record the name of
2597 * the reference that it points to. If we see an update of
2598 * head_ref within the transaction, then split_head_update()
2599 * arranges for the reflog of HEAD to be updated, too.
2601 head_ref
= refs_resolve_refdup(ref_store
, "HEAD",
2602 RESOLVE_REF_NO_RECURSE
,
2605 if (head_ref
&& !(head_type
& REF_ISSYMREF
)) {
2606 FREE_AND_NULL(head_ref
);
2610 * Acquire all locks, verify old values if provided, check
2611 * that new values are valid, and write new values to the
2612 * lockfiles, ready to be activated. Only keep one lockfile
2613 * open at a time to avoid running out of file descriptors.
2614 * Note that lock_ref_for_update() might append more updates
2615 * to the transaction.
2617 for (i
= 0; i
< transaction
->nr
; i
++) {
2618 struct ref_update
*update
= transaction
->updates
[i
];
2620 ret
= lock_ref_for_update(refs
, update
, transaction
,
2621 head_ref
, &affected_refnames
, err
);
2625 if (update
->flags
& REF_DELETING
&&
2626 !(update
->flags
& REF_LOG_ONLY
) &&
2627 !(update
->flags
& REF_IS_PRUNING
)) {
2629 * This reference has to be deleted from
2630 * packed-refs if it exists there.
2632 if (!packed_transaction
) {
2633 packed_transaction
= ref_store_transaction_begin(
2634 refs
->packed_ref_store
, err
);
2635 if (!packed_transaction
) {
2636 ret
= TRANSACTION_GENERIC_ERROR
;
2640 backend_data
->packed_transaction
=
2644 ref_transaction_add_update(
2645 packed_transaction
, update
->refname
,
2646 REF_HAVE_NEW
| REF_NO_DEREF
,
2647 &update
->new_oid
, NULL
,
2652 if (packed_transaction
) {
2653 if (packed_refs_lock(refs
->packed_ref_store
, 0, err
)) {
2654 ret
= TRANSACTION_GENERIC_ERROR
;
2657 backend_data
->packed_refs_locked
= 1;
2659 if (is_packed_transaction_needed(refs
->packed_ref_store
,
2660 packed_transaction
)) {
2661 ret
= ref_transaction_prepare(packed_transaction
, err
);
2664 * We can skip rewriting the `packed-refs`
2665 * file. But we do need to leave it locked, so
2666 * that somebody else doesn't pack a reference
2667 * that we are trying to delete.
2669 if (ref_transaction_abort(packed_transaction
, err
)) {
2670 ret
= TRANSACTION_GENERIC_ERROR
;
2673 backend_data
->packed_transaction
= NULL
;
2679 string_list_clear(&affected_refnames
, 0);
2682 files_transaction_cleanup(refs
, transaction
);
2684 transaction
->state
= REF_TRANSACTION_PREPARED
;
2689 static int files_transaction_finish(struct ref_store
*ref_store
,
2690 struct ref_transaction
*transaction
,
2693 struct files_ref_store
*refs
=
2694 files_downcast(ref_store
, 0, "ref_transaction_finish");
2697 struct strbuf sb
= STRBUF_INIT
;
2698 struct files_transaction_backend_data
*backend_data
;
2699 struct ref_transaction
*packed_transaction
;
2704 if (!transaction
->nr
) {
2705 transaction
->state
= REF_TRANSACTION_CLOSED
;
2709 backend_data
= transaction
->backend_data
;
2710 packed_transaction
= backend_data
->packed_transaction
;
2712 /* Perform updates first so live commits remain referenced */
2713 for (i
= 0; i
< transaction
->nr
; i
++) {
2714 struct ref_update
*update
= transaction
->updates
[i
];
2715 struct ref_lock
*lock
= update
->backend_data
;
2717 if (update
->flags
& REF_NEEDS_COMMIT
||
2718 update
->flags
& REF_LOG_ONLY
) {
2719 if (files_log_ref_write(refs
,
2723 update
->msg
, update
->flags
,
2725 char *old_msg
= strbuf_detach(err
, NULL
);
2727 strbuf_addf(err
, "cannot update the ref '%s': %s",
2728 lock
->ref_name
, old_msg
);
2731 update
->backend_data
= NULL
;
2732 ret
= TRANSACTION_GENERIC_ERROR
;
2736 if (update
->flags
& REF_NEEDS_COMMIT
) {
2737 clear_loose_ref_cache(refs
);
2738 if (commit_ref(lock
)) {
2739 strbuf_addf(err
, "couldn't set '%s'", lock
->ref_name
);
2741 update
->backend_data
= NULL
;
2742 ret
= TRANSACTION_GENERIC_ERROR
;
2749 * Now that updates are safely completed, we can perform
2750 * deletes. First delete the reflogs of any references that
2751 * will be deleted, since (in the unexpected event of an
2752 * error) leaving a reference without a reflog is less bad
2753 * than leaving a reflog without a reference (the latter is a
2754 * mildly invalid repository state):
2756 for (i
= 0; i
< transaction
->nr
; i
++) {
2757 struct ref_update
*update
= transaction
->updates
[i
];
2758 if (update
->flags
& REF_DELETING
&&
2759 !(update
->flags
& REF_LOG_ONLY
) &&
2760 !(update
->flags
& REF_IS_PRUNING
)) {
2762 files_reflog_path(refs
, &sb
, update
->refname
);
2763 if (!unlink_or_warn(sb
.buf
))
2764 try_remove_empty_parents(refs
, update
->refname
,
2765 REMOVE_EMPTY_PARENTS_REFLOG
);
2770 * Perform deletes now that updates are safely completed.
2772 * First delete any packed versions of the references, while
2773 * retaining the packed-refs lock:
2775 if (packed_transaction
) {
2776 ret
= ref_transaction_commit(packed_transaction
, err
);
2777 ref_transaction_free(packed_transaction
);
2778 packed_transaction
= NULL
;
2779 backend_data
->packed_transaction
= NULL
;
2784 /* Now delete the loose versions of the references: */
2785 for (i
= 0; i
< transaction
->nr
; i
++) {
2786 struct ref_update
*update
= transaction
->updates
[i
];
2787 struct ref_lock
*lock
= update
->backend_data
;
2789 if (update
->flags
& REF_DELETING
&&
2790 !(update
->flags
& REF_LOG_ONLY
)) {
2791 if (!(update
->type
& REF_ISPACKED
) ||
2792 update
->type
& REF_ISSYMREF
) {
2793 /* It is a loose reference. */
2795 files_ref_path(refs
, &sb
, lock
->ref_name
);
2796 if (unlink_or_msg(sb
.buf
, err
)) {
2797 ret
= TRANSACTION_GENERIC_ERROR
;
2800 update
->flags
|= REF_DELETED_LOOSE
;
2805 clear_loose_ref_cache(refs
);
2808 files_transaction_cleanup(refs
, transaction
);
2810 for (i
= 0; i
< transaction
->nr
; i
++) {
2811 struct ref_update
*update
= transaction
->updates
[i
];
2813 if (update
->flags
& REF_DELETED_LOOSE
) {
2815 * The loose reference was deleted. Delete any
2816 * empty parent directories. (Note that this
2817 * can only work because we have already
2818 * removed the lockfile.)
2820 try_remove_empty_parents(refs
, update
->refname
,
2821 REMOVE_EMPTY_PARENTS_REF
);
2825 strbuf_release(&sb
);
2829 static int files_transaction_abort(struct ref_store
*ref_store
,
2830 struct ref_transaction
*transaction
,
2833 struct files_ref_store
*refs
=
2834 files_downcast(ref_store
, 0, "ref_transaction_abort");
2836 files_transaction_cleanup(refs
, transaction
);
2840 static int ref_present(const char *refname
,
2841 const struct object_id
*oid
, int flags
, void *cb_data
)
2843 struct string_list
*affected_refnames
= cb_data
;
2845 return string_list_has_string(affected_refnames
, refname
);
2848 static int files_initial_transaction_commit(struct ref_store
*ref_store
,
2849 struct ref_transaction
*transaction
,
2852 struct files_ref_store
*refs
=
2853 files_downcast(ref_store
, REF_STORE_WRITE
,
2854 "initial_ref_transaction_commit");
2857 struct string_list affected_refnames
= STRING_LIST_INIT_NODUP
;
2858 struct ref_transaction
*packed_transaction
= NULL
;
2862 if (transaction
->state
!= REF_TRANSACTION_OPEN
)
2863 BUG("commit called for transaction that is not open");
2865 /* Fail if a refname appears more than once in the transaction: */
2866 for (i
= 0; i
< transaction
->nr
; i
++)
2867 string_list_append(&affected_refnames
,
2868 transaction
->updates
[i
]->refname
);
2869 string_list_sort(&affected_refnames
);
2870 if (ref_update_reject_duplicates(&affected_refnames
, err
)) {
2871 ret
= TRANSACTION_GENERIC_ERROR
;
2876 * It's really undefined to call this function in an active
2877 * repository or when there are existing references: we are
2878 * only locking and changing packed-refs, so (1) any
2879 * simultaneous processes might try to change a reference at
2880 * the same time we do, and (2) any existing loose versions of
2881 * the references that we are setting would have precedence
2882 * over our values. But some remote helpers create the remote
2883 * "HEAD" and "master" branches before calling this function,
2884 * so here we really only check that none of the references
2885 * that we are creating already exists.
2887 if (refs_for_each_rawref(&refs
->base
, ref_present
,
2888 &affected_refnames
))
2889 BUG("initial ref transaction called with existing refs");
2891 packed_transaction
= ref_store_transaction_begin(refs
->packed_ref_store
, err
);
2892 if (!packed_transaction
) {
2893 ret
= TRANSACTION_GENERIC_ERROR
;
2897 for (i
= 0; i
< transaction
->nr
; i
++) {
2898 struct ref_update
*update
= transaction
->updates
[i
];
2900 if ((update
->flags
& REF_HAVE_OLD
) &&
2901 !is_null_oid(&update
->old_oid
))
2902 BUG("initial ref transaction with old_sha1 set");
2903 if (refs_verify_refname_available(&refs
->base
, update
->refname
,
2904 &affected_refnames
, NULL
,
2906 ret
= TRANSACTION_NAME_CONFLICT
;
2911 * Add a reference creation for this reference to the
2912 * packed-refs transaction:
2914 ref_transaction_add_update(packed_transaction
, update
->refname
,
2915 update
->flags
& ~REF_HAVE_OLD
,
2916 &update
->new_oid
, &update
->old_oid
,
2920 if (packed_refs_lock(refs
->packed_ref_store
, 0, err
)) {
2921 ret
= TRANSACTION_GENERIC_ERROR
;
2925 if (initial_ref_transaction_commit(packed_transaction
, err
)) {
2926 ret
= TRANSACTION_GENERIC_ERROR
;
2929 packed_refs_unlock(refs
->packed_ref_store
);
2931 if (packed_transaction
)
2932 ref_transaction_free(packed_transaction
);
2933 transaction
->state
= REF_TRANSACTION_CLOSED
;
2934 string_list_clear(&affected_refnames
, 0);
2938 struct expire_reflog_cb
{
2940 reflog_expiry_should_prune_fn
*should_prune_fn
;
2943 struct object_id last_kept_oid
;
2946 static int expire_reflog_ent(struct object_id
*ooid
, struct object_id
*noid
,
2947 const char *email
, timestamp_t timestamp
, int tz
,
2948 const char *message
, void *cb_data
)
2950 struct expire_reflog_cb
*cb
= cb_data
;
2951 struct expire_reflog_policy_cb
*policy_cb
= cb
->policy_cb
;
2953 if (cb
->flags
& EXPIRE_REFLOGS_REWRITE
)
2954 ooid
= &cb
->last_kept_oid
;
2956 if ((*cb
->should_prune_fn
)(ooid
, noid
, email
, timestamp
, tz
,
2957 message
, policy_cb
)) {
2959 printf("would prune %s", message
);
2960 else if (cb
->flags
& EXPIRE_REFLOGS_VERBOSE
)
2961 printf("prune %s", message
);
2964 fprintf(cb
->newlog
, "%s %s %s %"PRItime
" %+05d\t%s",
2965 oid_to_hex(ooid
), oid_to_hex(noid
),
2966 email
, timestamp
, tz
, message
);
2967 oidcpy(&cb
->last_kept_oid
, noid
);
2969 if (cb
->flags
& EXPIRE_REFLOGS_VERBOSE
)
2970 printf("keep %s", message
);
2975 static int files_reflog_expire(struct ref_store
*ref_store
,
2976 const char *refname
, const struct object_id
*oid
,
2978 reflog_expiry_prepare_fn prepare_fn
,
2979 reflog_expiry_should_prune_fn should_prune_fn
,
2980 reflog_expiry_cleanup_fn cleanup_fn
,
2981 void *policy_cb_data
)
2983 struct files_ref_store
*refs
=
2984 files_downcast(ref_store
, REF_STORE_WRITE
, "reflog_expire");
2985 struct lock_file reflog_lock
= LOCK_INIT
;
2986 struct expire_reflog_cb cb
;
2987 struct ref_lock
*lock
;
2988 struct strbuf log_file_sb
= STRBUF_INIT
;
2992 struct strbuf err
= STRBUF_INIT
;
2994 memset(&cb
, 0, sizeof(cb
));
2996 cb
.policy_cb
= policy_cb_data
;
2997 cb
.should_prune_fn
= should_prune_fn
;
3000 * The reflog file is locked by holding the lock on the
3001 * reference itself, plus we might need to update the
3002 * reference if --updateref was specified:
3004 lock
= lock_ref_oid_basic(refs
, refname
, oid
,
3005 NULL
, NULL
, REF_NO_DEREF
,
3008 error("cannot lock ref '%s': %s", refname
, err
.buf
);
3009 strbuf_release(&err
);
3012 if (!refs_reflog_exists(ref_store
, refname
)) {
3017 files_reflog_path(refs
, &log_file_sb
, refname
);
3018 log_file
= strbuf_detach(&log_file_sb
, NULL
);
3019 if (!(flags
& EXPIRE_REFLOGS_DRY_RUN
)) {
3021 * Even though holding $GIT_DIR/logs/$reflog.lock has
3022 * no locking implications, we use the lock_file
3023 * machinery here anyway because it does a lot of the
3024 * work we need, including cleaning up if the program
3025 * exits unexpectedly.
3027 if (hold_lock_file_for_update(&reflog_lock
, log_file
, 0) < 0) {
3028 struct strbuf err
= STRBUF_INIT
;
3029 unable_to_lock_message(log_file
, errno
, &err
);
3030 error("%s", err
.buf
);
3031 strbuf_release(&err
);
3034 cb
.newlog
= fdopen_lock_file(&reflog_lock
, "w");
3036 error("cannot fdopen %s (%s)",
3037 get_lock_file_path(&reflog_lock
), strerror(errno
));
3042 (*prepare_fn
)(refname
, oid
, cb
.policy_cb
);
3043 refs_for_each_reflog_ent(ref_store
, refname
, expire_reflog_ent
, &cb
);
3044 (*cleanup_fn
)(cb
.policy_cb
);
3046 if (!(flags
& EXPIRE_REFLOGS_DRY_RUN
)) {
3048 * It doesn't make sense to adjust a reference pointed
3049 * to by a symbolic ref based on expiring entries in
3050 * the symbolic reference's reflog. Nor can we update
3051 * a reference if there are no remaining reflog
3054 int update
= (flags
& EXPIRE_REFLOGS_UPDATE_REF
) &&
3055 !(type
& REF_ISSYMREF
) &&
3056 !is_null_oid(&cb
.last_kept_oid
);
3058 if (close_lock_file_gently(&reflog_lock
)) {
3059 status
|= error("couldn't write %s: %s", log_file
,
3061 rollback_lock_file(&reflog_lock
);
3062 } else if (update
&&
3063 (write_in_full(get_lock_file_fd(&lock
->lk
),
3064 oid_to_hex(&cb
.last_kept_oid
), the_hash_algo
->hexsz
) < 0 ||
3065 write_str_in_full(get_lock_file_fd(&lock
->lk
), "\n") < 0 ||
3066 close_ref_gently(lock
) < 0)) {
3067 status
|= error("couldn't write %s",
3068 get_lock_file_path(&lock
->lk
));
3069 rollback_lock_file(&reflog_lock
);
3070 } else if (commit_lock_file(&reflog_lock
)) {
3071 status
|= error("unable to write reflog '%s' (%s)",
3072 log_file
, strerror(errno
));
3073 } else if (update
&& commit_ref(lock
)) {
3074 status
|= error("couldn't set %s", lock
->ref_name
);
3082 rollback_lock_file(&reflog_lock
);
3088 static int files_init_db(struct ref_store
*ref_store
, struct strbuf
*err
)
3090 struct files_ref_store
*refs
=
3091 files_downcast(ref_store
, REF_STORE_WRITE
, "init_db");
3092 struct strbuf sb
= STRBUF_INIT
;
3095 * Create .git/refs/{heads,tags}
3097 files_ref_path(refs
, &sb
, "refs/heads");
3098 safe_create_dir(sb
.buf
, 1);
3101 files_ref_path(refs
, &sb
, "refs/tags");
3102 safe_create_dir(sb
.buf
, 1);
3104 strbuf_release(&sb
);
3108 struct ref_storage_be refs_be_files
= {
3111 files_ref_store_create
,
3113 files_transaction_prepare
,
3114 files_transaction_finish
,
3115 files_transaction_abort
,
3116 files_initial_transaction_commit
,
3119 files_create_symref
,
3124 files_ref_iterator_begin
,
3127 files_reflog_iterator_begin
,
3128 files_for_each_reflog_ent
,
3129 files_for_each_reflog_ent_reverse
,
3130 files_reflog_exists
,
3131 files_create_reflog
,
3132 files_delete_reflog
,