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
;
66 * Future: need to be in "struct repository"
67 * when doing a full libification.
69 struct files_ref_store
{
70 struct ref_store base
;
71 unsigned int store_flags
;
76 struct ref_cache
*loose
;
78 struct ref_store
*packed_ref_store
;
81 static void clear_loose_ref_cache(struct files_ref_store
*refs
)
84 free_ref_cache(refs
->loose
);
90 * Create a new submodule ref cache and add it to the internal
93 static struct ref_store
*files_ref_store_create(const char *gitdir
,
96 struct files_ref_store
*refs
= xcalloc(1, sizeof(*refs
));
97 struct ref_store
*ref_store
= (struct ref_store
*)refs
;
98 struct strbuf sb
= STRBUF_INIT
;
100 base_ref_store_init(ref_store
, &refs_be_files
);
101 refs
->store_flags
= flags
;
103 refs
->gitdir
= xstrdup(gitdir
);
104 get_common_dir_noenv(&sb
, gitdir
);
105 refs
->gitcommondir
= strbuf_detach(&sb
, NULL
);
106 strbuf_addf(&sb
, "%s/packed-refs", refs
->gitcommondir
);
107 refs
->packed_ref_store
= packed_ref_store_create(sb
.buf
, flags
);
110 chdir_notify_reparent("files-backend $GIT_DIR",
112 chdir_notify_reparent("files-backend $GIT_COMMONDIR",
113 &refs
->gitcommondir
);
119 * Die if refs is not the main ref store. caller is used in any
120 * necessary error messages.
122 static void files_assert_main_repository(struct files_ref_store
*refs
,
125 if (refs
->store_flags
& REF_STORE_MAIN
)
128 BUG("operation %s only allowed for main ref store", caller
);
132 * Downcast ref_store to files_ref_store. Die if ref_store is not a
133 * files_ref_store. required_flags is compared with ref_store's
134 * store_flags to ensure the ref_store has all required capabilities.
135 * "caller" is used in any necessary error messages.
137 static struct files_ref_store
*files_downcast(struct ref_store
*ref_store
,
138 unsigned int required_flags
,
141 struct files_ref_store
*refs
;
143 if (ref_store
->be
!= &refs_be_files
)
144 BUG("ref_store is type \"%s\" not \"files\" in %s",
145 ref_store
->be
->name
, caller
);
147 refs
= (struct files_ref_store
*)ref_store
;
149 if ((refs
->store_flags
& required_flags
) != required_flags
)
150 BUG("operation %s requires abilities 0x%x, but only have 0x%x",
151 caller
, required_flags
, refs
->store_flags
);
156 static void files_reflog_path(struct files_ref_store
*refs
,
160 switch (ref_type(refname
)) {
161 case REF_TYPE_PER_WORKTREE
:
162 case REF_TYPE_PSEUDOREF
:
163 strbuf_addf(sb
, "%s/logs/%s", refs
->gitdir
, refname
);
165 case REF_TYPE_NORMAL
:
166 strbuf_addf(sb
, "%s/logs/%s", refs
->gitcommondir
, refname
);
169 BUG("unknown ref type %d of ref %s",
170 ref_type(refname
), refname
);
174 static void files_ref_path(struct files_ref_store
*refs
,
178 switch (ref_type(refname
)) {
179 case REF_TYPE_PER_WORKTREE
:
180 case REF_TYPE_PSEUDOREF
:
181 strbuf_addf(sb
, "%s/%s", refs
->gitdir
, refname
);
183 case REF_TYPE_NORMAL
:
184 strbuf_addf(sb
, "%s/%s", refs
->gitcommondir
, refname
);
187 BUG("unknown ref type %d of ref %s",
188 ref_type(refname
), refname
);
193 * Read the loose references from the namespace dirname into dir
194 * (without recursing). dirname must end with '/'. dir must be the
195 * directory entry corresponding to dirname.
197 static void loose_fill_ref_dir(struct ref_store
*ref_store
,
198 struct ref_dir
*dir
, const char *dirname
)
200 struct files_ref_store
*refs
=
201 files_downcast(ref_store
, REF_STORE_READ
, "fill_ref_dir");
204 int dirnamelen
= strlen(dirname
);
205 struct strbuf refname
;
206 struct strbuf path
= STRBUF_INIT
;
209 files_ref_path(refs
, &path
, dirname
);
210 path_baselen
= path
.len
;
212 d
= opendir(path
.buf
);
214 strbuf_release(&path
);
218 strbuf_init(&refname
, dirnamelen
+ 257);
219 strbuf_add(&refname
, dirname
, dirnamelen
);
221 while ((de
= readdir(d
)) != NULL
) {
222 struct object_id oid
;
226 if (de
->d_name
[0] == '.')
228 if (ends_with(de
->d_name
, ".lock"))
230 strbuf_addstr(&refname
, de
->d_name
);
231 strbuf_addstr(&path
, de
->d_name
);
232 if (stat(path
.buf
, &st
) < 0) {
233 ; /* silently ignore */
234 } else if (S_ISDIR(st
.st_mode
)) {
235 strbuf_addch(&refname
, '/');
236 add_entry_to_dir(dir
,
237 create_dir_entry(dir
->cache
, refname
.buf
,
240 if (!refs_resolve_ref_unsafe(&refs
->base
,
245 flag
|= REF_ISBROKEN
;
246 } else if (is_null_oid(&oid
)) {
248 * It is so astronomically unlikely
249 * that null_oid is the OID of an
250 * actual object that we consider its
251 * appearance in a loose reference
252 * file to be repo corruption
253 * (probably due to a software bug).
255 flag
|= REF_ISBROKEN
;
258 if (check_refname_format(refname
.buf
,
259 REFNAME_ALLOW_ONELEVEL
)) {
260 if (!refname_is_safe(refname
.buf
))
261 die("loose refname is dangerous: %s", refname
.buf
);
263 flag
|= REF_BAD_NAME
| REF_ISBROKEN
;
265 add_entry_to_dir(dir
,
266 create_ref_entry(refname
.buf
, &oid
, flag
));
268 strbuf_setlen(&refname
, dirnamelen
);
269 strbuf_setlen(&path
, path_baselen
);
271 strbuf_release(&refname
);
272 strbuf_release(&path
);
276 * Manually add refs/bisect, which, being per-worktree, might
277 * not appear in the directory listing for refs/ in the main
280 if (!strcmp(dirname
, "refs/")) {
281 int pos
= search_ref_dir(dir
, "refs/bisect/", 12);
284 struct ref_entry
*child_entry
= create_dir_entry(
285 dir
->cache
, "refs/bisect/", 12, 1);
286 add_entry_to_dir(dir
, child_entry
);
291 static struct ref_cache
*get_loose_ref_cache(struct files_ref_store
*refs
)
295 * Mark the top-level directory complete because we
296 * are about to read the only subdirectory that can
299 refs
->loose
= create_ref_cache(&refs
->base
, loose_fill_ref_dir
);
301 /* We're going to fill the top level ourselves: */
302 refs
->loose
->root
->flag
&= ~REF_INCOMPLETE
;
305 * Add an incomplete entry for "refs/" (to be filled
308 add_entry_to_dir(get_ref_dir(refs
->loose
->root
),
309 create_dir_entry(refs
->loose
, "refs/", 5, 1));
314 static int files_read_raw_ref(struct ref_store
*ref_store
,
315 const char *refname
, struct object_id
*oid
,
316 struct strbuf
*referent
, unsigned int *type
)
318 struct files_ref_store
*refs
=
319 files_downcast(ref_store
, REF_STORE_READ
, "read_raw_ref");
320 struct strbuf sb_contents
= STRBUF_INIT
;
321 struct strbuf sb_path
= STRBUF_INIT
;
329 int remaining_retries
= 3;
332 strbuf_reset(&sb_path
);
334 files_ref_path(refs
, &sb_path
, refname
);
340 * We might have to loop back here to avoid a race
341 * condition: first we lstat() the file, then we try
342 * to read it as a link or as a file. But if somebody
343 * changes the type of the file (file <-> directory
344 * <-> symlink) between the lstat() and reading, then
345 * we don't want to report that as an error but rather
346 * try again starting with the lstat().
348 * We'll keep a count of the retries, though, just to avoid
349 * any confusing situation sending us into an infinite loop.
352 if (remaining_retries
-- <= 0)
355 if (lstat(path
, &st
) < 0) {
358 if (refs_read_raw_ref(refs
->packed_ref_store
, refname
,
359 oid
, referent
, type
)) {
367 /* Follow "normalized" - ie "refs/.." symlinks by hand */
368 if (S_ISLNK(st
.st_mode
)) {
369 strbuf_reset(&sb_contents
);
370 if (strbuf_readlink(&sb_contents
, path
, 0) < 0) {
371 if (errno
== ENOENT
|| errno
== EINVAL
)
372 /* inconsistent with lstat; retry */
377 if (starts_with(sb_contents
.buf
, "refs/") &&
378 !check_refname_format(sb_contents
.buf
, 0)) {
379 strbuf_swap(&sb_contents
, referent
);
380 *type
|= REF_ISSYMREF
;
385 * It doesn't look like a refname; fall through to just
386 * treating it like a non-symlink, and reading whatever it
391 /* Is it a directory? */
392 if (S_ISDIR(st
.st_mode
)) {
394 * Even though there is a directory where the loose
395 * ref is supposed to be, there could still be a
398 if (refs_read_raw_ref(refs
->packed_ref_store
, refname
,
399 oid
, referent
, type
)) {
408 * Anything else, just open it and try to use it as
411 fd
= open(path
, O_RDONLY
);
413 if (errno
== ENOENT
&& !S_ISLNK(st
.st_mode
))
414 /* inconsistent with lstat; retry */
419 strbuf_reset(&sb_contents
);
420 if (strbuf_read(&sb_contents
, fd
, 256) < 0) {
421 int save_errno
= errno
;
427 strbuf_rtrim(&sb_contents
);
428 buf
= sb_contents
.buf
;
429 if (starts_with(buf
, "ref:")) {
431 while (isspace(*buf
))
434 strbuf_reset(referent
);
435 strbuf_addstr(referent
, buf
);
436 *type
|= REF_ISSYMREF
;
442 * Please note that FETCH_HEAD has additional
443 * data after the sha.
445 if (parse_oid_hex(buf
, oid
, &p
) ||
446 (*p
!= '\0' && !isspace(*p
))) {
447 *type
|= REF_ISBROKEN
;
456 strbuf_release(&sb_path
);
457 strbuf_release(&sb_contents
);
462 static void unlock_ref(struct ref_lock
*lock
)
464 rollback_lock_file(&lock
->lk
);
465 free(lock
->ref_name
);
470 * Lock refname, without following symrefs, and set *lock_p to point
471 * at a newly-allocated lock object. Fill in lock->old_oid, referent,
472 * and type similarly to read_raw_ref().
474 * The caller must verify that refname is a "safe" reference name (in
475 * the sense of refname_is_safe()) before calling this function.
477 * If the reference doesn't already exist, verify that refname doesn't
478 * have a D/F conflict with any existing references. extras and skip
479 * are passed to refs_verify_refname_available() for this check.
481 * If mustexist is not set and the reference is not found or is
482 * broken, lock the reference anyway but clear old_oid.
484 * Return 0 on success. On failure, write an error message to err and
485 * return TRANSACTION_NAME_CONFLICT or TRANSACTION_GENERIC_ERROR.
487 * Implementation note: This function is basically
492 * but it includes a lot more code to
493 * - Deal with possible races with other processes
494 * - Avoid calling refs_verify_refname_available() when it can be
495 * avoided, namely if we were successfully able to read the ref
496 * - Generate informative error messages in the case of failure
498 static int lock_raw_ref(struct files_ref_store
*refs
,
499 const char *refname
, int mustexist
,
500 const struct string_list
*extras
,
501 const struct string_list
*skip
,
502 struct ref_lock
**lock_p
,
503 struct strbuf
*referent
,
507 struct ref_lock
*lock
;
508 struct strbuf ref_file
= STRBUF_INIT
;
509 int attempts_remaining
= 3;
510 int ret
= TRANSACTION_GENERIC_ERROR
;
513 files_assert_main_repository(refs
, "lock_raw_ref");
517 /* First lock the file so it can't change out from under us. */
519 *lock_p
= lock
= xcalloc(1, sizeof(*lock
));
521 lock
->ref_name
= xstrdup(refname
);
522 files_ref_path(refs
, &ref_file
, refname
);
525 switch (safe_create_leading_directories(ref_file
.buf
)) {
530 * Suppose refname is "refs/foo/bar". We just failed
531 * to create the containing directory, "refs/foo",
532 * because there was a non-directory in the way. This
533 * indicates a D/F conflict, probably because of
534 * another reference such as "refs/foo". There is no
535 * reason to expect this error to be transitory.
537 if (refs_verify_refname_available(&refs
->base
, refname
,
538 extras
, skip
, err
)) {
541 * To the user the relevant error is
542 * that the "mustexist" reference is
546 strbuf_addf(err
, "unable to resolve reference '%s'",
550 * The error message set by
551 * refs_verify_refname_available() is
554 ret
= TRANSACTION_NAME_CONFLICT
;
558 * The file that is in the way isn't a loose
559 * reference. Report it as a low-level
562 strbuf_addf(err
, "unable to create lock file %s.lock; "
563 "non-directory in the way",
568 /* Maybe another process was tidying up. Try again. */
569 if (--attempts_remaining
> 0)
573 strbuf_addf(err
, "unable to create directory for %s",
578 if (hold_lock_file_for_update_timeout(
579 &lock
->lk
, ref_file
.buf
, LOCK_NO_DEREF
,
580 get_files_ref_lock_timeout_ms()) < 0) {
581 if (errno
== ENOENT
&& --attempts_remaining
> 0) {
583 * Maybe somebody just deleted one of the
584 * directories leading to ref_file. Try
589 unable_to_lock_message(ref_file
.buf
, errno
, err
);
595 * Now we hold the lock and can read the reference without
596 * fear that its value will change.
599 if (files_read_raw_ref(&refs
->base
, refname
,
600 &lock
->old_oid
, referent
, type
)) {
601 if (errno
== ENOENT
) {
603 /* Garden variety missing reference. */
604 strbuf_addf(err
, "unable to resolve reference '%s'",
609 * Reference is missing, but that's OK. We
610 * know that there is not a conflict with
611 * another loose reference because
612 * (supposing that we are trying to lock
613 * reference "refs/foo/bar"):
615 * - We were successfully able to create
616 * the lockfile refs/foo/bar.lock, so we
617 * know there cannot be a loose reference
620 * - We got ENOENT and not EISDIR, so we
621 * know that there cannot be a loose
622 * reference named "refs/foo/bar/baz".
625 } else if (errno
== EISDIR
) {
627 * There is a directory in the way. It might have
628 * contained references that have been deleted. If
629 * we don't require that the reference already
630 * exists, try to remove the directory so that it
631 * doesn't cause trouble when we want to rename the
632 * lockfile into place later.
635 /* Garden variety missing reference. */
636 strbuf_addf(err
, "unable to resolve reference '%s'",
639 } else if (remove_dir_recursively(&ref_file
,
640 REMOVE_DIR_EMPTY_ONLY
)) {
641 if (refs_verify_refname_available(
642 &refs
->base
, refname
,
643 extras
, skip
, err
)) {
645 * The error message set by
646 * verify_refname_available() is OK.
648 ret
= TRANSACTION_NAME_CONFLICT
;
652 * We can't delete the directory,
653 * but we also don't know of any
654 * references that it should
657 strbuf_addf(err
, "there is a non-empty directory '%s' "
658 "blocking reference '%s'",
659 ref_file
.buf
, refname
);
663 } else if (errno
== EINVAL
&& (*type
& REF_ISBROKEN
)) {
664 strbuf_addf(err
, "unable to resolve reference '%s': "
665 "reference broken", refname
);
668 strbuf_addf(err
, "unable to resolve reference '%s': %s",
669 refname
, strerror(errno
));
674 * If the ref did not exist and we are creating it,
675 * make sure there is no existing packed ref that
676 * conflicts with refname:
678 if (refs_verify_refname_available(
679 refs
->packed_ref_store
, refname
,
692 strbuf_release(&ref_file
);
696 struct files_ref_iterator
{
697 struct ref_iterator base
;
699 struct ref_iterator
*iter0
;
703 static int files_ref_iterator_advance(struct ref_iterator
*ref_iterator
)
705 struct files_ref_iterator
*iter
=
706 (struct files_ref_iterator
*)ref_iterator
;
709 while ((ok
= ref_iterator_advance(iter
->iter0
)) == ITER_OK
) {
710 if (iter
->flags
& DO_FOR_EACH_PER_WORKTREE_ONLY
&&
711 ref_type(iter
->iter0
->refname
) != REF_TYPE_PER_WORKTREE
)
714 if (!(iter
->flags
& DO_FOR_EACH_INCLUDE_BROKEN
) &&
715 !ref_resolves_to_object(iter
->iter0
->refname
,
720 iter
->base
.refname
= iter
->iter0
->refname
;
721 iter
->base
.oid
= iter
->iter0
->oid
;
722 iter
->base
.flags
= iter
->iter0
->flags
;
727 if (ref_iterator_abort(ref_iterator
) != ITER_DONE
)
733 static int files_ref_iterator_peel(struct ref_iterator
*ref_iterator
,
734 struct object_id
*peeled
)
736 struct files_ref_iterator
*iter
=
737 (struct files_ref_iterator
*)ref_iterator
;
739 return ref_iterator_peel(iter
->iter0
, peeled
);
742 static int files_ref_iterator_abort(struct ref_iterator
*ref_iterator
)
744 struct files_ref_iterator
*iter
=
745 (struct files_ref_iterator
*)ref_iterator
;
749 ok
= ref_iterator_abort(iter
->iter0
);
751 base_ref_iterator_free(ref_iterator
);
755 static struct ref_iterator_vtable files_ref_iterator_vtable
= {
756 files_ref_iterator_advance
,
757 files_ref_iterator_peel
,
758 files_ref_iterator_abort
761 static struct ref_iterator
*files_ref_iterator_begin(
762 struct ref_store
*ref_store
,
763 const char *prefix
, unsigned int flags
)
765 struct files_ref_store
*refs
;
766 struct ref_iterator
*loose_iter
, *packed_iter
, *overlay_iter
;
767 struct files_ref_iterator
*iter
;
768 struct ref_iterator
*ref_iterator
;
769 unsigned int required_flags
= REF_STORE_READ
;
771 if (!(flags
& DO_FOR_EACH_INCLUDE_BROKEN
))
772 required_flags
|= REF_STORE_ODB
;
774 refs
= files_downcast(ref_store
, required_flags
, "ref_iterator_begin");
777 * We must make sure that all loose refs are read before
778 * accessing the packed-refs file; this avoids a race
779 * condition if loose refs are migrated to the packed-refs
780 * file by a simultaneous process, but our in-memory view is
781 * from before the migration. We ensure this as follows:
782 * First, we call start the loose refs iteration with its
783 * `prime_ref` argument set to true. This causes the loose
784 * references in the subtree to be pre-read into the cache.
785 * (If they've already been read, that's OK; we only need to
786 * guarantee that they're read before the packed refs, not
787 * *how much* before.) After that, we call
788 * packed_ref_iterator_begin(), which internally checks
789 * whether the packed-ref cache is up to date with what is on
790 * disk, and re-reads it if not.
793 loose_iter
= cache_ref_iterator_begin(get_loose_ref_cache(refs
),
797 * The packed-refs file might contain broken references, for
798 * example an old version of a reference that points at an
799 * object that has since been garbage-collected. This is OK as
800 * long as there is a corresponding loose reference that
801 * overrides it, and we don't want to emit an error message in
802 * this case. So ask the packed_ref_store for all of its
803 * references, and (if needed) do our own check for broken
804 * ones in files_ref_iterator_advance(), after we have merged
805 * the packed and loose references.
807 packed_iter
= refs_ref_iterator_begin(
808 refs
->packed_ref_store
, prefix
, 0,
809 DO_FOR_EACH_INCLUDE_BROKEN
);
811 overlay_iter
= overlay_ref_iterator_begin(loose_iter
, packed_iter
);
813 iter
= xcalloc(1, sizeof(*iter
));
814 ref_iterator
= &iter
->base
;
815 base_ref_iterator_init(ref_iterator
, &files_ref_iterator_vtable
,
816 overlay_iter
->ordered
);
817 iter
->iter0
= overlay_iter
;
824 * Verify that the reference locked by lock has the value old_oid
825 * (unless it is NULL). Fail if the reference doesn't exist and
826 * mustexist is set. Return 0 on success. On error, write an error
827 * message to err, set errno, and return a negative value.
829 static int verify_lock(struct ref_store
*ref_store
, struct ref_lock
*lock
,
830 const struct object_id
*old_oid
, int mustexist
,
835 if (refs_read_ref_full(ref_store
, lock
->ref_name
,
836 mustexist
? RESOLVE_REF_READING
: 0,
837 &lock
->old_oid
, NULL
)) {
839 int save_errno
= errno
;
840 strbuf_addf(err
, "can't verify ref '%s'", lock
->ref_name
);
844 oidclr(&lock
->old_oid
);
848 if (old_oid
&& oidcmp(&lock
->old_oid
, old_oid
)) {
849 strbuf_addf(err
, "ref '%s' is at %s but expected %s",
851 oid_to_hex(&lock
->old_oid
),
852 oid_to_hex(old_oid
));
859 static int remove_empty_directories(struct strbuf
*path
)
862 * we want to create a file but there is a directory there;
863 * if that is an empty directory (or a directory that contains
864 * only empty directories), remove them.
866 return remove_dir_recursively(path
, REMOVE_DIR_EMPTY_ONLY
);
869 static int create_reflock(const char *path
, void *cb
)
871 struct lock_file
*lk
= cb
;
873 return hold_lock_file_for_update_timeout(
874 lk
, path
, LOCK_NO_DEREF
,
875 get_files_ref_lock_timeout_ms()) < 0 ? -1 : 0;
879 * Locks a ref returning the lock on success and NULL on failure.
880 * On failure errno is set to something meaningful.
882 static struct ref_lock
*lock_ref_oid_basic(struct files_ref_store
*refs
,
884 const struct object_id
*old_oid
,
885 const struct string_list
*extras
,
886 const struct string_list
*skip
,
887 unsigned int flags
, int *type
,
890 struct strbuf ref_file
= STRBUF_INIT
;
891 struct ref_lock
*lock
;
893 int mustexist
= (old_oid
&& !is_null_oid(old_oid
));
894 int resolve_flags
= RESOLVE_REF_NO_RECURSE
;
897 files_assert_main_repository(refs
, "lock_ref_oid_basic");
900 lock
= xcalloc(1, sizeof(struct ref_lock
));
903 resolve_flags
|= RESOLVE_REF_READING
;
904 if (flags
& REF_DELETING
)
905 resolve_flags
|= RESOLVE_REF_ALLOW_BAD_NAME
;
907 files_ref_path(refs
, &ref_file
, refname
);
908 resolved
= !!refs_resolve_ref_unsafe(&refs
->base
,
909 refname
, resolve_flags
,
910 &lock
->old_oid
, type
);
911 if (!resolved
&& errno
== EISDIR
) {
913 * we are trying to lock foo but we used to
914 * have foo/bar which now does not exist;
915 * it is normal for the empty directory 'foo'
918 if (remove_empty_directories(&ref_file
)) {
920 if (!refs_verify_refname_available(
922 refname
, extras
, skip
, err
))
923 strbuf_addf(err
, "there are still refs under '%s'",
927 resolved
= !!refs_resolve_ref_unsafe(&refs
->base
,
928 refname
, resolve_flags
,
929 &lock
->old_oid
, type
);
933 if (last_errno
!= ENOTDIR
||
934 !refs_verify_refname_available(&refs
->base
, refname
,
936 strbuf_addf(err
, "unable to resolve reference '%s': %s",
937 refname
, strerror(last_errno
));
943 * If the ref did not exist and we are creating it, make sure
944 * there is no existing packed ref whose name begins with our
945 * refname, nor a packed ref whose name is a proper prefix of
948 if (is_null_oid(&lock
->old_oid
) &&
949 refs_verify_refname_available(refs
->packed_ref_store
, refname
,
950 extras
, skip
, err
)) {
951 last_errno
= ENOTDIR
;
955 lock
->ref_name
= xstrdup(refname
);
957 if (raceproof_create_file(ref_file
.buf
, create_reflock
, &lock
->lk
)) {
959 unable_to_lock_message(ref_file
.buf
, errno
, err
);
963 if (verify_lock(&refs
->base
, lock
, old_oid
, mustexist
, err
)) {
974 strbuf_release(&ref_file
);
979 struct ref_to_prune
{
980 struct ref_to_prune
*next
;
981 struct object_id oid
;
982 char name
[FLEX_ARRAY
];
986 REMOVE_EMPTY_PARENTS_REF
= 0x01,
987 REMOVE_EMPTY_PARENTS_REFLOG
= 0x02
991 * Remove empty parent directories associated with the specified
992 * reference and/or its reflog, but spare [logs/]refs/ and immediate
993 * subdirs. flags is a combination of REMOVE_EMPTY_PARENTS_REF and/or
994 * REMOVE_EMPTY_PARENTS_REFLOG.
996 static void try_remove_empty_parents(struct files_ref_store
*refs
,
1000 struct strbuf buf
= STRBUF_INIT
;
1001 struct strbuf sb
= STRBUF_INIT
;
1005 strbuf_addstr(&buf
, refname
);
1007 for (i
= 0; i
< 2; i
++) { /* refs/{heads,tags,...}/ */
1008 while (*p
&& *p
!= '/')
1010 /* tolerate duplicate slashes; see check_refname_format() */
1014 q
= buf
.buf
+ buf
.len
;
1015 while (flags
& (REMOVE_EMPTY_PARENTS_REF
| REMOVE_EMPTY_PARENTS_REFLOG
)) {
1016 while (q
> p
&& *q
!= '/')
1018 while (q
> p
&& *(q
-1) == '/')
1022 strbuf_setlen(&buf
, q
- buf
.buf
);
1025 files_ref_path(refs
, &sb
, buf
.buf
);
1026 if ((flags
& REMOVE_EMPTY_PARENTS_REF
) && rmdir(sb
.buf
))
1027 flags
&= ~REMOVE_EMPTY_PARENTS_REF
;
1030 files_reflog_path(refs
, &sb
, buf
.buf
);
1031 if ((flags
& REMOVE_EMPTY_PARENTS_REFLOG
) && rmdir(sb
.buf
))
1032 flags
&= ~REMOVE_EMPTY_PARENTS_REFLOG
;
1034 strbuf_release(&buf
);
1035 strbuf_release(&sb
);
1038 /* make sure nobody touched the ref, and unlink */
1039 static void prune_ref(struct files_ref_store
*refs
, struct ref_to_prune
*r
)
1041 struct ref_transaction
*transaction
;
1042 struct strbuf err
= STRBUF_INIT
;
1045 if (check_refname_format(r
->name
, 0))
1048 transaction
= ref_store_transaction_begin(&refs
->base
, &err
);
1051 ref_transaction_add_update(
1052 transaction
, r
->name
,
1053 REF_NO_DEREF
| REF_HAVE_NEW
| REF_HAVE_OLD
| REF_IS_PRUNING
,
1054 &null_oid
, &r
->oid
, NULL
);
1055 if (ref_transaction_commit(transaction
, &err
))
1062 error("%s", err
.buf
);
1063 strbuf_release(&err
);
1064 ref_transaction_free(transaction
);
1069 * Prune the loose versions of the references in the linked list
1070 * `*refs_to_prune`, freeing the entries in the list as we go.
1072 static void prune_refs(struct files_ref_store
*refs
, struct ref_to_prune
**refs_to_prune
)
1074 while (*refs_to_prune
) {
1075 struct ref_to_prune
*r
= *refs_to_prune
;
1076 *refs_to_prune
= r
->next
;
1083 * Return true if the specified reference should be packed.
1085 static int should_pack_ref(const char *refname
,
1086 const struct object_id
*oid
, unsigned int ref_flags
,
1087 unsigned int pack_flags
)
1089 /* Do not pack per-worktree refs: */
1090 if (ref_type(refname
) != REF_TYPE_NORMAL
)
1093 /* Do not pack non-tags unless PACK_REFS_ALL is set: */
1094 if (!(pack_flags
& PACK_REFS_ALL
) && !starts_with(refname
, "refs/tags/"))
1097 /* Do not pack symbolic refs: */
1098 if (ref_flags
& REF_ISSYMREF
)
1101 /* Do not pack broken refs: */
1102 if (!ref_resolves_to_object(refname
, oid
, ref_flags
))
1108 static int files_pack_refs(struct ref_store
*ref_store
, unsigned int flags
)
1110 struct files_ref_store
*refs
=
1111 files_downcast(ref_store
, REF_STORE_WRITE
| REF_STORE_ODB
,
1113 struct ref_iterator
*iter
;
1115 struct ref_to_prune
*refs_to_prune
= NULL
;
1116 struct strbuf err
= STRBUF_INIT
;
1117 struct ref_transaction
*transaction
;
1119 transaction
= ref_store_transaction_begin(refs
->packed_ref_store
, &err
);
1123 packed_refs_lock(refs
->packed_ref_store
, LOCK_DIE_ON_ERROR
, &err
);
1125 iter
= cache_ref_iterator_begin(get_loose_ref_cache(refs
), NULL
, 0);
1126 while ((ok
= ref_iterator_advance(iter
)) == ITER_OK
) {
1128 * If the loose reference can be packed, add an entry
1129 * in the packed ref cache. If the reference should be
1130 * pruned, also add it to refs_to_prune.
1132 if (!should_pack_ref(iter
->refname
, iter
->oid
, iter
->flags
,
1137 * Add a reference creation for this reference to the
1138 * packed-refs transaction:
1140 if (ref_transaction_update(transaction
, iter
->refname
,
1142 REF_NO_DEREF
, NULL
, &err
))
1143 die("failure preparing to create packed reference %s: %s",
1144 iter
->refname
, err
.buf
);
1146 /* Schedule the loose reference for pruning if requested. */
1147 if ((flags
& PACK_REFS_PRUNE
)) {
1148 struct ref_to_prune
*n
;
1149 FLEX_ALLOC_STR(n
, name
, iter
->refname
);
1150 oidcpy(&n
->oid
, iter
->oid
);
1151 n
->next
= refs_to_prune
;
1155 if (ok
!= ITER_DONE
)
1156 die("error while iterating over references");
1158 if (ref_transaction_commit(transaction
, &err
))
1159 die("unable to write new packed-refs: %s", err
.buf
);
1161 ref_transaction_free(transaction
);
1163 packed_refs_unlock(refs
->packed_ref_store
);
1165 prune_refs(refs
, &refs_to_prune
);
1166 strbuf_release(&err
);
1170 static int files_delete_refs(struct ref_store
*ref_store
, const char *msg
,
1171 struct string_list
*refnames
, unsigned int flags
)
1173 struct files_ref_store
*refs
=
1174 files_downcast(ref_store
, REF_STORE_WRITE
, "delete_refs");
1175 struct strbuf err
= STRBUF_INIT
;
1181 if (packed_refs_lock(refs
->packed_ref_store
, 0, &err
))
1184 if (refs_delete_refs(refs
->packed_ref_store
, msg
, refnames
, flags
)) {
1185 packed_refs_unlock(refs
->packed_ref_store
);
1189 packed_refs_unlock(refs
->packed_ref_store
);
1191 for (i
= 0; i
< refnames
->nr
; i
++) {
1192 const char *refname
= refnames
->items
[i
].string
;
1194 if (refs_delete_ref(&refs
->base
, msg
, refname
, NULL
, flags
))
1195 result
|= error(_("could not remove reference %s"), refname
);
1198 strbuf_release(&err
);
1203 * If we failed to rewrite the packed-refs file, then it is
1204 * unsafe to try to remove loose refs, because doing so might
1205 * expose an obsolete packed value for a reference that might
1206 * even point at an object that has been garbage collected.
1208 if (refnames
->nr
== 1)
1209 error(_("could not delete reference %s: %s"),
1210 refnames
->items
[0].string
, err
.buf
);
1212 error(_("could not delete references: %s"), err
.buf
);
1214 strbuf_release(&err
);
1219 * People using contrib's git-new-workdir have .git/logs/refs ->
1220 * /some/other/path/.git/logs/refs, and that may live on another device.
1222 * IOW, to avoid cross device rename errors, the temporary renamed log must
1223 * live into logs/refs.
1225 #define TMP_RENAMED_LOG "refs/.tmp-renamed-log"
1228 const char *tmp_renamed_log
;
1232 static int rename_tmp_log_callback(const char *path
, void *cb_data
)
1234 struct rename_cb
*cb
= cb_data
;
1236 if (rename(cb
->tmp_renamed_log
, path
)) {
1238 * rename(a, b) when b is an existing directory ought
1239 * to result in ISDIR, but Solaris 5.8 gives ENOTDIR.
1240 * Sheesh. Record the true errno for error reporting,
1241 * but report EISDIR to raceproof_create_file() so
1242 * that it knows to retry.
1244 cb
->true_errno
= errno
;
1245 if (errno
== ENOTDIR
)
1253 static int rename_tmp_log(struct files_ref_store
*refs
, const char *newrefname
)
1255 struct strbuf path
= STRBUF_INIT
;
1256 struct strbuf tmp
= STRBUF_INIT
;
1257 struct rename_cb cb
;
1260 files_reflog_path(refs
, &path
, newrefname
);
1261 files_reflog_path(refs
, &tmp
, TMP_RENAMED_LOG
);
1262 cb
.tmp_renamed_log
= tmp
.buf
;
1263 ret
= raceproof_create_file(path
.buf
, rename_tmp_log_callback
, &cb
);
1265 if (errno
== EISDIR
)
1266 error("directory not empty: %s", path
.buf
);
1268 error("unable to move logfile %s to %s: %s",
1270 strerror(cb
.true_errno
));
1273 strbuf_release(&path
);
1274 strbuf_release(&tmp
);
1278 static int write_ref_to_lockfile(struct ref_lock
*lock
,
1279 const struct object_id
*oid
, struct strbuf
*err
);
1280 static int commit_ref_update(struct files_ref_store
*refs
,
1281 struct ref_lock
*lock
,
1282 const struct object_id
*oid
, const char *logmsg
,
1283 struct strbuf
*err
);
1285 static int files_copy_or_rename_ref(struct ref_store
*ref_store
,
1286 const char *oldrefname
, const char *newrefname
,
1287 const char *logmsg
, int copy
)
1289 struct files_ref_store
*refs
=
1290 files_downcast(ref_store
, REF_STORE_WRITE
, "rename_ref");
1291 struct object_id oid
, orig_oid
;
1292 int flag
= 0, logmoved
= 0;
1293 struct ref_lock
*lock
;
1294 struct stat loginfo
;
1295 struct strbuf sb_oldref
= STRBUF_INIT
;
1296 struct strbuf sb_newref
= STRBUF_INIT
;
1297 struct strbuf tmp_renamed_log
= STRBUF_INIT
;
1299 struct strbuf err
= STRBUF_INIT
;
1301 files_reflog_path(refs
, &sb_oldref
, oldrefname
);
1302 files_reflog_path(refs
, &sb_newref
, newrefname
);
1303 files_reflog_path(refs
, &tmp_renamed_log
, TMP_RENAMED_LOG
);
1305 log
= !lstat(sb_oldref
.buf
, &loginfo
);
1306 if (log
&& S_ISLNK(loginfo
.st_mode
)) {
1307 ret
= error("reflog for %s is a symlink", oldrefname
);
1311 if (!refs_resolve_ref_unsafe(&refs
->base
, oldrefname
,
1312 RESOLVE_REF_READING
| RESOLVE_REF_NO_RECURSE
,
1313 &orig_oid
, &flag
)) {
1314 ret
= error("refname %s not found", oldrefname
);
1318 if (flag
& REF_ISSYMREF
) {
1320 ret
= error("refname %s is a symbolic ref, copying it is not supported",
1323 ret
= error("refname %s is a symbolic ref, renaming it is not supported",
1327 if (!refs_rename_ref_available(&refs
->base
, oldrefname
, newrefname
)) {
1332 if (!copy
&& log
&& rename(sb_oldref
.buf
, tmp_renamed_log
.buf
)) {
1333 ret
= error("unable to move logfile logs/%s to logs/"TMP_RENAMED_LOG
": %s",
1334 oldrefname
, strerror(errno
));
1338 if (copy
&& log
&& copy_file(tmp_renamed_log
.buf
, sb_oldref
.buf
, 0644)) {
1339 ret
= error("unable to copy logfile logs/%s to logs/"TMP_RENAMED_LOG
": %s",
1340 oldrefname
, strerror(errno
));
1344 if (!copy
&& refs_delete_ref(&refs
->base
, logmsg
, oldrefname
,
1345 &orig_oid
, REF_NO_DEREF
)) {
1346 error("unable to delete old %s", oldrefname
);
1351 * Since we are doing a shallow lookup, oid is not the
1352 * correct value to pass to delete_ref as old_oid. But that
1353 * doesn't matter, because an old_oid check wouldn't add to
1354 * the safety anyway; we want to delete the reference whatever
1355 * its current value.
1357 if (!copy
&& !refs_read_ref_full(&refs
->base
, newrefname
,
1358 RESOLVE_REF_READING
| RESOLVE_REF_NO_RECURSE
,
1360 refs_delete_ref(&refs
->base
, NULL
, newrefname
,
1361 NULL
, REF_NO_DEREF
)) {
1362 if (errno
== EISDIR
) {
1363 struct strbuf path
= STRBUF_INIT
;
1366 files_ref_path(refs
, &path
, newrefname
);
1367 result
= remove_empty_directories(&path
);
1368 strbuf_release(&path
);
1371 error("Directory not empty: %s", newrefname
);
1375 error("unable to delete existing %s", newrefname
);
1380 if (log
&& rename_tmp_log(refs
, newrefname
))
1385 lock
= lock_ref_oid_basic(refs
, newrefname
, NULL
, NULL
, NULL
,
1386 REF_NO_DEREF
, NULL
, &err
);
1389 error("unable to copy '%s' to '%s': %s", oldrefname
, newrefname
, err
.buf
);
1391 error("unable to rename '%s' to '%s': %s", oldrefname
, newrefname
, err
.buf
);
1392 strbuf_release(&err
);
1395 oidcpy(&lock
->old_oid
, &orig_oid
);
1397 if (write_ref_to_lockfile(lock
, &orig_oid
, &err
) ||
1398 commit_ref_update(refs
, lock
, &orig_oid
, logmsg
, &err
)) {
1399 error("unable to write current sha1 into %s: %s", newrefname
, err
.buf
);
1400 strbuf_release(&err
);
1408 lock
= lock_ref_oid_basic(refs
, oldrefname
, NULL
, NULL
, NULL
,
1409 REF_NO_DEREF
, NULL
, &err
);
1411 error("unable to lock %s for rollback: %s", oldrefname
, err
.buf
);
1412 strbuf_release(&err
);
1416 flag
= log_all_ref_updates
;
1417 log_all_ref_updates
= LOG_REFS_NONE
;
1418 if (write_ref_to_lockfile(lock
, &orig_oid
, &err
) ||
1419 commit_ref_update(refs
, lock
, &orig_oid
, NULL
, &err
)) {
1420 error("unable to write current sha1 into %s: %s", oldrefname
, err
.buf
);
1421 strbuf_release(&err
);
1423 log_all_ref_updates
= flag
;
1426 if (logmoved
&& rename(sb_newref
.buf
, sb_oldref
.buf
))
1427 error("unable to restore logfile %s from %s: %s",
1428 oldrefname
, newrefname
, strerror(errno
));
1429 if (!logmoved
&& log
&&
1430 rename(tmp_renamed_log
.buf
, sb_oldref
.buf
))
1431 error("unable to restore logfile %s from logs/"TMP_RENAMED_LOG
": %s",
1432 oldrefname
, strerror(errno
));
1435 strbuf_release(&sb_newref
);
1436 strbuf_release(&sb_oldref
);
1437 strbuf_release(&tmp_renamed_log
);
1442 static int files_rename_ref(struct ref_store
*ref_store
,
1443 const char *oldrefname
, const char *newrefname
,
1446 return files_copy_or_rename_ref(ref_store
, oldrefname
,
1447 newrefname
, logmsg
, 0);
1450 static int files_copy_ref(struct ref_store
*ref_store
,
1451 const char *oldrefname
, const char *newrefname
,
1454 return files_copy_or_rename_ref(ref_store
, oldrefname
,
1455 newrefname
, logmsg
, 1);
1458 static int close_ref_gently(struct ref_lock
*lock
)
1460 if (close_lock_file_gently(&lock
->lk
))
1465 static int commit_ref(struct ref_lock
*lock
)
1467 char *path
= get_locked_file_path(&lock
->lk
);
1470 if (!lstat(path
, &st
) && S_ISDIR(st
.st_mode
)) {
1472 * There is a directory at the path we want to rename
1473 * the lockfile to. Hopefully it is empty; try to
1476 size_t len
= strlen(path
);
1477 struct strbuf sb_path
= STRBUF_INIT
;
1479 strbuf_attach(&sb_path
, path
, len
, len
);
1482 * If this fails, commit_lock_file() will also fail
1483 * and will report the problem.
1485 remove_empty_directories(&sb_path
);
1486 strbuf_release(&sb_path
);
1491 if (commit_lock_file(&lock
->lk
))
1496 static int open_or_create_logfile(const char *path
, void *cb
)
1500 *fd
= open(path
, O_APPEND
| O_WRONLY
| O_CREAT
, 0666);
1501 return (*fd
< 0) ? -1 : 0;
1505 * Create a reflog for a ref. If force_create = 0, only create the
1506 * reflog for certain refs (those for which should_autocreate_reflog
1507 * returns non-zero). Otherwise, create it regardless of the reference
1508 * name. If the logfile already existed or was created, return 0 and
1509 * set *logfd to the file descriptor opened for appending to the file.
1510 * If no logfile exists and we decided not to create one, return 0 and
1511 * set *logfd to -1. On failure, fill in *err, set *logfd to -1, and
1514 static int log_ref_setup(struct files_ref_store
*refs
,
1515 const char *refname
, int force_create
,
1516 int *logfd
, struct strbuf
*err
)
1518 struct strbuf logfile_sb
= STRBUF_INIT
;
1521 files_reflog_path(refs
, &logfile_sb
, refname
);
1522 logfile
= strbuf_detach(&logfile_sb
, NULL
);
1524 if (force_create
|| should_autocreate_reflog(refname
)) {
1525 if (raceproof_create_file(logfile
, open_or_create_logfile
, logfd
)) {
1526 if (errno
== ENOENT
)
1527 strbuf_addf(err
, "unable to create directory for '%s': "
1528 "%s", logfile
, strerror(errno
));
1529 else if (errno
== EISDIR
)
1530 strbuf_addf(err
, "there are still logs under '%s'",
1533 strbuf_addf(err
, "unable to append to '%s': %s",
1534 logfile
, strerror(errno
));
1539 *logfd
= open(logfile
, O_APPEND
| O_WRONLY
, 0666);
1541 if (errno
== ENOENT
|| errno
== EISDIR
) {
1543 * The logfile doesn't already exist,
1544 * but that is not an error; it only
1545 * means that we won't write log
1550 strbuf_addf(err
, "unable to append to '%s': %s",
1551 logfile
, strerror(errno
));
1558 adjust_shared_perm(logfile
);
1568 static int files_create_reflog(struct ref_store
*ref_store
,
1569 const char *refname
, int force_create
,
1572 struct files_ref_store
*refs
=
1573 files_downcast(ref_store
, REF_STORE_WRITE
, "create_reflog");
1576 if (log_ref_setup(refs
, refname
, force_create
, &fd
, err
))
1585 static int log_ref_write_fd(int fd
, const struct object_id
*old_oid
,
1586 const struct object_id
*new_oid
,
1587 const char *committer
, const char *msg
)
1589 int msglen
, written
;
1590 unsigned maxlen
, len
;
1593 msglen
= msg
? strlen(msg
) : 0;
1594 maxlen
= strlen(committer
) + msglen
+ 100;
1595 logrec
= xmalloc(maxlen
);
1596 len
= xsnprintf(logrec
, maxlen
, "%s %s %s\n",
1597 oid_to_hex(old_oid
),
1598 oid_to_hex(new_oid
),
1601 len
+= copy_reflog_msg(logrec
+ len
- 1, msg
) - 1;
1603 written
= len
<= maxlen
? write_in_full(fd
, logrec
, len
) : -1;
1611 static int files_log_ref_write(struct files_ref_store
*refs
,
1612 const char *refname
, const struct object_id
*old_oid
,
1613 const struct object_id
*new_oid
, const char *msg
,
1614 int flags
, struct strbuf
*err
)
1618 if (log_all_ref_updates
== LOG_REFS_UNSET
)
1619 log_all_ref_updates
= is_bare_repository() ? LOG_REFS_NONE
: LOG_REFS_NORMAL
;
1621 result
= log_ref_setup(refs
, refname
,
1622 flags
& REF_FORCE_CREATE_REFLOG
,
1630 result
= log_ref_write_fd(logfd
, old_oid
, new_oid
,
1631 git_committer_info(0), msg
);
1633 struct strbuf sb
= STRBUF_INIT
;
1634 int save_errno
= errno
;
1636 files_reflog_path(refs
, &sb
, refname
);
1637 strbuf_addf(err
, "unable to append to '%s': %s",
1638 sb
.buf
, strerror(save_errno
));
1639 strbuf_release(&sb
);
1644 struct strbuf sb
= STRBUF_INIT
;
1645 int save_errno
= errno
;
1647 files_reflog_path(refs
, &sb
, refname
);
1648 strbuf_addf(err
, "unable to append to '%s': %s",
1649 sb
.buf
, strerror(save_errno
));
1650 strbuf_release(&sb
);
1657 * Write oid into the open lockfile, then close the lockfile. On
1658 * errors, rollback the lockfile, fill in *err and return -1.
1660 static int write_ref_to_lockfile(struct ref_lock
*lock
,
1661 const struct object_id
*oid
, struct strbuf
*err
)
1663 static char term
= '\n';
1667 o
= parse_object(oid
);
1670 "trying to write ref '%s' with nonexistent object %s",
1671 lock
->ref_name
, oid_to_hex(oid
));
1675 if (o
->type
!= OBJ_COMMIT
&& is_branch(lock
->ref_name
)) {
1677 "trying to write non-commit object %s to branch '%s'",
1678 oid_to_hex(oid
), lock
->ref_name
);
1682 fd
= get_lock_file_fd(&lock
->lk
);
1683 if (write_in_full(fd
, oid_to_hex(oid
), GIT_SHA1_HEXSZ
) < 0 ||
1684 write_in_full(fd
, &term
, 1) < 0 ||
1685 close_ref_gently(lock
) < 0) {
1687 "couldn't write '%s'", get_lock_file_path(&lock
->lk
));
1695 * Commit a change to a loose reference that has already been written
1696 * to the loose reference lockfile. Also update the reflogs if
1697 * necessary, using the specified lockmsg (which can be NULL).
1699 static int commit_ref_update(struct files_ref_store
*refs
,
1700 struct ref_lock
*lock
,
1701 const struct object_id
*oid
, const char *logmsg
,
1704 files_assert_main_repository(refs
, "commit_ref_update");
1706 clear_loose_ref_cache(refs
);
1707 if (files_log_ref_write(refs
, lock
->ref_name
,
1708 &lock
->old_oid
, oid
,
1710 char *old_msg
= strbuf_detach(err
, NULL
);
1711 strbuf_addf(err
, "cannot update the ref '%s': %s",
1712 lock
->ref_name
, old_msg
);
1718 if (strcmp(lock
->ref_name
, "HEAD") != 0) {
1720 * Special hack: If a branch is updated directly and HEAD
1721 * points to it (may happen on the remote side of a push
1722 * for example) then logically the HEAD reflog should be
1724 * A generic solution implies reverse symref information,
1725 * but finding all symrefs pointing to the given branch
1726 * would be rather costly for this rare event (the direct
1727 * update of a branch) to be worth it. So let's cheat and
1728 * check with HEAD only which should cover 99% of all usage
1729 * scenarios (even 100% of the default ones).
1732 const char *head_ref
;
1734 head_ref
= refs_resolve_ref_unsafe(&refs
->base
, "HEAD",
1735 RESOLVE_REF_READING
,
1737 if (head_ref
&& (head_flag
& REF_ISSYMREF
) &&
1738 !strcmp(head_ref
, lock
->ref_name
)) {
1739 struct strbuf log_err
= STRBUF_INIT
;
1740 if (files_log_ref_write(refs
, "HEAD",
1741 &lock
->old_oid
, oid
,
1742 logmsg
, 0, &log_err
)) {
1743 error("%s", log_err
.buf
);
1744 strbuf_release(&log_err
);
1749 if (commit_ref(lock
)) {
1750 strbuf_addf(err
, "couldn't set '%s'", lock
->ref_name
);
1759 static int create_ref_symlink(struct ref_lock
*lock
, const char *target
)
1762 #ifndef NO_SYMLINK_HEAD
1763 char *ref_path
= get_locked_file_path(&lock
->lk
);
1765 ret
= symlink(target
, ref_path
);
1769 fprintf(stderr
, "no symlink - falling back to symbolic ref\n");
1774 static void update_symref_reflog(struct files_ref_store
*refs
,
1775 struct ref_lock
*lock
, const char *refname
,
1776 const char *target
, const char *logmsg
)
1778 struct strbuf err
= STRBUF_INIT
;
1779 struct object_id new_oid
;
1781 !refs_read_ref_full(&refs
->base
, target
,
1782 RESOLVE_REF_READING
, &new_oid
, NULL
) &&
1783 files_log_ref_write(refs
, refname
, &lock
->old_oid
,
1784 &new_oid
, logmsg
, 0, &err
)) {
1785 error("%s", err
.buf
);
1786 strbuf_release(&err
);
1790 static int create_symref_locked(struct files_ref_store
*refs
,
1791 struct ref_lock
*lock
, const char *refname
,
1792 const char *target
, const char *logmsg
)
1794 if (prefer_symlink_refs
&& !create_ref_symlink(lock
, target
)) {
1795 update_symref_reflog(refs
, lock
, refname
, target
, logmsg
);
1799 if (!fdopen_lock_file(&lock
->lk
, "w"))
1800 return error("unable to fdopen %s: %s",
1801 lock
->lk
.tempfile
->filename
.buf
, strerror(errno
));
1803 update_symref_reflog(refs
, lock
, refname
, target
, logmsg
);
1805 /* no error check; commit_ref will check ferror */
1806 fprintf(lock
->lk
.tempfile
->fp
, "ref: %s\n", target
);
1807 if (commit_ref(lock
) < 0)
1808 return error("unable to write symref for %s: %s", refname
,
1813 static int files_create_symref(struct ref_store
*ref_store
,
1814 const char *refname
, const char *target
,
1817 struct files_ref_store
*refs
=
1818 files_downcast(ref_store
, REF_STORE_WRITE
, "create_symref");
1819 struct strbuf err
= STRBUF_INIT
;
1820 struct ref_lock
*lock
;
1823 lock
= lock_ref_oid_basic(refs
, refname
, NULL
,
1824 NULL
, NULL
, REF_NO_DEREF
, NULL
,
1827 error("%s", err
.buf
);
1828 strbuf_release(&err
);
1832 ret
= create_symref_locked(refs
, lock
, refname
, target
, logmsg
);
1837 static int files_reflog_exists(struct ref_store
*ref_store
,
1838 const char *refname
)
1840 struct files_ref_store
*refs
=
1841 files_downcast(ref_store
, REF_STORE_READ
, "reflog_exists");
1842 struct strbuf sb
= STRBUF_INIT
;
1846 files_reflog_path(refs
, &sb
, refname
);
1847 ret
= !lstat(sb
.buf
, &st
) && S_ISREG(st
.st_mode
);
1848 strbuf_release(&sb
);
1852 static int files_delete_reflog(struct ref_store
*ref_store
,
1853 const char *refname
)
1855 struct files_ref_store
*refs
=
1856 files_downcast(ref_store
, REF_STORE_WRITE
, "delete_reflog");
1857 struct strbuf sb
= STRBUF_INIT
;
1860 files_reflog_path(refs
, &sb
, refname
);
1861 ret
= remove_path(sb
.buf
);
1862 strbuf_release(&sb
);
1866 static int show_one_reflog_ent(struct strbuf
*sb
, each_reflog_ent_fn fn
, void *cb_data
)
1868 struct object_id ooid
, noid
;
1869 char *email_end
, *message
;
1870 timestamp_t timestamp
;
1872 const char *p
= sb
->buf
;
1874 /* old SP new SP name <email> SP time TAB msg LF */
1875 if (!sb
->len
|| sb
->buf
[sb
->len
- 1] != '\n' ||
1876 parse_oid_hex(p
, &ooid
, &p
) || *p
++ != ' ' ||
1877 parse_oid_hex(p
, &noid
, &p
) || *p
++ != ' ' ||
1878 !(email_end
= strchr(p
, '>')) ||
1879 email_end
[1] != ' ' ||
1880 !(timestamp
= parse_timestamp(email_end
+ 2, &message
, 10)) ||
1881 !message
|| message
[0] != ' ' ||
1882 (message
[1] != '+' && message
[1] != '-') ||
1883 !isdigit(message
[2]) || !isdigit(message
[3]) ||
1884 !isdigit(message
[4]) || !isdigit(message
[5]))
1885 return 0; /* corrupt? */
1886 email_end
[1] = '\0';
1887 tz
= strtol(message
+ 1, NULL
, 10);
1888 if (message
[6] != '\t')
1892 return fn(&ooid
, &noid
, p
, timestamp
, tz
, message
, cb_data
);
1895 static char *find_beginning_of_line(char *bob
, char *scan
)
1897 while (bob
< scan
&& *(--scan
) != '\n')
1898 ; /* keep scanning backwards */
1900 * Return either beginning of the buffer, or LF at the end of
1901 * the previous line.
1906 static int files_for_each_reflog_ent_reverse(struct ref_store
*ref_store
,
1907 const char *refname
,
1908 each_reflog_ent_fn fn
,
1911 struct files_ref_store
*refs
=
1912 files_downcast(ref_store
, REF_STORE_READ
,
1913 "for_each_reflog_ent_reverse");
1914 struct strbuf sb
= STRBUF_INIT
;
1917 int ret
= 0, at_tail
= 1;
1919 files_reflog_path(refs
, &sb
, refname
);
1920 logfp
= fopen(sb
.buf
, "r");
1921 strbuf_release(&sb
);
1925 /* Jump to the end */
1926 if (fseek(logfp
, 0, SEEK_END
) < 0)
1927 ret
= error("cannot seek back reflog for %s: %s",
1928 refname
, strerror(errno
));
1930 while (!ret
&& 0 < pos
) {
1936 /* Fill next block from the end */
1937 cnt
= (sizeof(buf
) < pos
) ? sizeof(buf
) : pos
;
1938 if (fseek(logfp
, pos
- cnt
, SEEK_SET
)) {
1939 ret
= error("cannot seek back reflog for %s: %s",
1940 refname
, strerror(errno
));
1943 nread
= fread(buf
, cnt
, 1, logfp
);
1945 ret
= error("cannot read %d bytes from reflog for %s: %s",
1946 cnt
, refname
, strerror(errno
));
1951 scanp
= endp
= buf
+ cnt
;
1952 if (at_tail
&& scanp
[-1] == '\n')
1953 /* Looking at the final LF at the end of the file */
1957 while (buf
< scanp
) {
1959 * terminating LF of the previous line, or the beginning
1964 bp
= find_beginning_of_line(buf
, scanp
);
1968 * The newline is the end of the previous line,
1969 * so we know we have complete line starting
1970 * at (bp + 1). Prefix it onto any prior data
1971 * we collected for the line and process it.
1973 strbuf_splice(&sb
, 0, 0, bp
+ 1, endp
- (bp
+ 1));
1976 ret
= show_one_reflog_ent(&sb
, fn
, cb_data
);
1982 * We are at the start of the buffer, and the
1983 * start of the file; there is no previous
1984 * line, and we have everything for this one.
1985 * Process it, and we can end the loop.
1987 strbuf_splice(&sb
, 0, 0, buf
, endp
- buf
);
1988 ret
= show_one_reflog_ent(&sb
, fn
, cb_data
);
1995 * We are at the start of the buffer, and there
1996 * is more file to read backwards. Which means
1997 * we are in the middle of a line. Note that we
1998 * may get here even if *bp was a newline; that
1999 * just means we are at the exact end of the
2000 * previous line, rather than some spot in the
2003 * Save away what we have to be combined with
2004 * the data from the next read.
2006 strbuf_splice(&sb
, 0, 0, buf
, endp
- buf
);
2013 BUG("reverse reflog parser had leftover data");
2016 strbuf_release(&sb
);
2020 static int files_for_each_reflog_ent(struct ref_store
*ref_store
,
2021 const char *refname
,
2022 each_reflog_ent_fn fn
, void *cb_data
)
2024 struct files_ref_store
*refs
=
2025 files_downcast(ref_store
, REF_STORE_READ
,
2026 "for_each_reflog_ent");
2028 struct strbuf sb
= STRBUF_INIT
;
2031 files_reflog_path(refs
, &sb
, refname
);
2032 logfp
= fopen(sb
.buf
, "r");
2033 strbuf_release(&sb
);
2037 while (!ret
&& !strbuf_getwholeline(&sb
, logfp
, '\n'))
2038 ret
= show_one_reflog_ent(&sb
, fn
, cb_data
);
2040 strbuf_release(&sb
);
2044 struct files_reflog_iterator
{
2045 struct ref_iterator base
;
2047 struct ref_store
*ref_store
;
2048 struct dir_iterator
*dir_iterator
;
2049 struct object_id oid
;
2052 static int files_reflog_iterator_advance(struct ref_iterator
*ref_iterator
)
2054 struct files_reflog_iterator
*iter
=
2055 (struct files_reflog_iterator
*)ref_iterator
;
2056 struct dir_iterator
*diter
= iter
->dir_iterator
;
2059 while ((ok
= dir_iterator_advance(diter
)) == ITER_OK
) {
2062 if (!S_ISREG(diter
->st
.st_mode
))
2064 if (diter
->basename
[0] == '.')
2066 if (ends_with(diter
->basename
, ".lock"))
2069 if (refs_read_ref_full(iter
->ref_store
,
2070 diter
->relative_path
, 0,
2071 &iter
->oid
, &flags
)) {
2072 error("bad ref for %s", diter
->path
.buf
);
2076 iter
->base
.refname
= diter
->relative_path
;
2077 iter
->base
.oid
= &iter
->oid
;
2078 iter
->base
.flags
= flags
;
2082 iter
->dir_iterator
= NULL
;
2083 if (ref_iterator_abort(ref_iterator
) == ITER_ERROR
)
2088 static int files_reflog_iterator_peel(struct ref_iterator
*ref_iterator
,
2089 struct object_id
*peeled
)
2091 BUG("ref_iterator_peel() called for reflog_iterator");
2094 static int files_reflog_iterator_abort(struct ref_iterator
*ref_iterator
)
2096 struct files_reflog_iterator
*iter
=
2097 (struct files_reflog_iterator
*)ref_iterator
;
2100 if (iter
->dir_iterator
)
2101 ok
= dir_iterator_abort(iter
->dir_iterator
);
2103 base_ref_iterator_free(ref_iterator
);
2107 static struct ref_iterator_vtable files_reflog_iterator_vtable
= {
2108 files_reflog_iterator_advance
,
2109 files_reflog_iterator_peel
,
2110 files_reflog_iterator_abort
2113 static struct ref_iterator
*reflog_iterator_begin(struct ref_store
*ref_store
,
2116 struct files_reflog_iterator
*iter
= xcalloc(1, sizeof(*iter
));
2117 struct ref_iterator
*ref_iterator
= &iter
->base
;
2118 struct strbuf sb
= STRBUF_INIT
;
2120 base_ref_iterator_init(ref_iterator
, &files_reflog_iterator_vtable
, 0);
2121 strbuf_addf(&sb
, "%s/logs", gitdir
);
2122 iter
->dir_iterator
= dir_iterator_begin(sb
.buf
);
2123 iter
->ref_store
= ref_store
;
2124 strbuf_release(&sb
);
2126 return ref_iterator
;
2129 static enum iterator_selection
reflog_iterator_select(
2130 struct ref_iterator
*iter_worktree
,
2131 struct ref_iterator
*iter_common
,
2134 if (iter_worktree
) {
2136 * We're a bit loose here. We probably should ignore
2137 * common refs if they are accidentally added as
2138 * per-worktree refs.
2140 return ITER_SELECT_0
;
2141 } else if (iter_common
) {
2142 if (ref_type(iter_common
->refname
) == REF_TYPE_NORMAL
)
2143 return ITER_SELECT_1
;
2146 * The main ref store may contain main worktree's
2147 * per-worktree refs, which should be ignored
2154 static struct ref_iterator
*files_reflog_iterator_begin(struct ref_store
*ref_store
)
2156 struct files_ref_store
*refs
=
2157 files_downcast(ref_store
, REF_STORE_READ
,
2158 "reflog_iterator_begin");
2160 if (!strcmp(refs
->gitdir
, refs
->gitcommondir
)) {
2161 return reflog_iterator_begin(ref_store
, refs
->gitcommondir
);
2163 return merge_ref_iterator_begin(
2165 reflog_iterator_begin(ref_store
, refs
->gitdir
),
2166 reflog_iterator_begin(ref_store
, refs
->gitcommondir
),
2167 reflog_iterator_select
, refs
);
2172 * If update is a direct update of head_ref (the reference pointed to
2173 * by HEAD), then add an extra REF_LOG_ONLY update for HEAD.
2175 static int split_head_update(struct ref_update
*update
,
2176 struct ref_transaction
*transaction
,
2177 const char *head_ref
,
2178 struct string_list
*affected_refnames
,
2181 struct string_list_item
*item
;
2182 struct ref_update
*new_update
;
2184 if ((update
->flags
& REF_LOG_ONLY
) ||
2185 (update
->flags
& REF_IS_PRUNING
) ||
2186 (update
->flags
& REF_UPDATE_VIA_HEAD
))
2189 if (strcmp(update
->refname
, head_ref
))
2193 * First make sure that HEAD is not already in the
2194 * transaction. This check is O(lg N) in the transaction
2195 * size, but it happens at most once per transaction.
2197 if (string_list_has_string(affected_refnames
, "HEAD")) {
2198 /* An entry already existed */
2200 "multiple updates for 'HEAD' (including one "
2201 "via its referent '%s') are not allowed",
2203 return TRANSACTION_NAME_CONFLICT
;
2206 new_update
= ref_transaction_add_update(
2207 transaction
, "HEAD",
2208 update
->flags
| REF_LOG_ONLY
| REF_NO_DEREF
,
2209 &update
->new_oid
, &update
->old_oid
,
2213 * Add "HEAD". This insertion is O(N) in the transaction
2214 * size, but it happens at most once per transaction.
2215 * Add new_update->refname instead of a literal "HEAD".
2217 if (strcmp(new_update
->refname
, "HEAD"))
2218 BUG("%s unexpectedly not 'HEAD'", new_update
->refname
);
2219 item
= string_list_insert(affected_refnames
, new_update
->refname
);
2220 item
->util
= new_update
;
2226 * update is for a symref that points at referent and doesn't have
2227 * REF_NO_DEREF set. Split it into two updates:
2228 * - The original update, but with REF_LOG_ONLY and REF_NO_DEREF set
2229 * - A new, separate update for the referent reference
2230 * Note that the new update will itself be subject to splitting when
2231 * the iteration gets to it.
2233 static int split_symref_update(struct files_ref_store
*refs
,
2234 struct ref_update
*update
,
2235 const char *referent
,
2236 struct ref_transaction
*transaction
,
2237 struct string_list
*affected_refnames
,
2240 struct string_list_item
*item
;
2241 struct ref_update
*new_update
;
2242 unsigned int new_flags
;
2245 * First make sure that referent is not already in the
2246 * transaction. This check is O(lg N) in the transaction
2247 * size, but it happens at most once per symref in a
2250 if (string_list_has_string(affected_refnames
, referent
)) {
2251 /* An entry already exists */
2253 "multiple updates for '%s' (including one "
2254 "via symref '%s') are not allowed",
2255 referent
, update
->refname
);
2256 return TRANSACTION_NAME_CONFLICT
;
2259 new_flags
= update
->flags
;
2260 if (!strcmp(update
->refname
, "HEAD")) {
2262 * Record that the new update came via HEAD, so that
2263 * when we process it, split_head_update() doesn't try
2264 * to add another reflog update for HEAD. Note that
2265 * this bit will be propagated if the new_update
2266 * itself needs to be split.
2268 new_flags
|= REF_UPDATE_VIA_HEAD
;
2271 new_update
= ref_transaction_add_update(
2272 transaction
, referent
, new_flags
,
2273 &update
->new_oid
, &update
->old_oid
,
2276 new_update
->parent_update
= update
;
2279 * Change the symbolic ref update to log only. Also, it
2280 * doesn't need to check its old OID value, as that will be
2281 * done when new_update is processed.
2283 update
->flags
|= REF_LOG_ONLY
| REF_NO_DEREF
;
2284 update
->flags
&= ~REF_HAVE_OLD
;
2287 * Add the referent. This insertion is O(N) in the transaction
2288 * size, but it happens at most once per symref in a
2289 * transaction. Make sure to add new_update->refname, which will
2290 * be valid as long as affected_refnames is in use, and NOT
2291 * referent, which might soon be freed by our caller.
2293 item
= string_list_insert(affected_refnames
, new_update
->refname
);
2295 BUG("%s unexpectedly found in affected_refnames",
2296 new_update
->refname
);
2297 item
->util
= new_update
;
2303 * Return the refname under which update was originally requested.
2305 static const char *original_update_refname(struct ref_update
*update
)
2307 while (update
->parent_update
)
2308 update
= update
->parent_update
;
2310 return update
->refname
;
2314 * Check whether the REF_HAVE_OLD and old_oid values stored in update
2315 * are consistent with oid, which is the reference's current value. If
2316 * everything is OK, return 0; otherwise, write an error message to
2317 * err and return -1.
2319 static int check_old_oid(struct ref_update
*update
, struct object_id
*oid
,
2322 if (!(update
->flags
& REF_HAVE_OLD
) ||
2323 !oidcmp(oid
, &update
->old_oid
))
2326 if (is_null_oid(&update
->old_oid
))
2327 strbuf_addf(err
, "cannot lock ref '%s': "
2328 "reference already exists",
2329 original_update_refname(update
));
2330 else if (is_null_oid(oid
))
2331 strbuf_addf(err
, "cannot lock ref '%s': "
2332 "reference is missing but expected %s",
2333 original_update_refname(update
),
2334 oid_to_hex(&update
->old_oid
));
2336 strbuf_addf(err
, "cannot lock ref '%s': "
2337 "is at %s but expected %s",
2338 original_update_refname(update
),
2340 oid_to_hex(&update
->old_oid
));
2346 * Prepare for carrying out update:
2347 * - Lock the reference referred to by update.
2348 * - Read the reference under lock.
2349 * - Check that its old OID value (if specified) is correct, and in
2350 * any case record it in update->lock->old_oid for later use when
2351 * writing the reflog.
2352 * - If it is a symref update without REF_NO_DEREF, split it up into a
2353 * REF_LOG_ONLY update of the symref and add a separate update for
2354 * the referent to transaction.
2355 * - If it is an update of head_ref, add a corresponding REF_LOG_ONLY
2358 static int lock_ref_for_update(struct files_ref_store
*refs
,
2359 struct ref_update
*update
,
2360 struct ref_transaction
*transaction
,
2361 const char *head_ref
,
2362 struct string_list
*affected_refnames
,
2365 struct strbuf referent
= STRBUF_INIT
;
2366 int mustexist
= (update
->flags
& REF_HAVE_OLD
) &&
2367 !is_null_oid(&update
->old_oid
);
2369 struct ref_lock
*lock
;
2371 files_assert_main_repository(refs
, "lock_ref_for_update");
2373 if ((update
->flags
& REF_HAVE_NEW
) && is_null_oid(&update
->new_oid
))
2374 update
->flags
|= REF_DELETING
;
2377 ret
= split_head_update(update
, transaction
, head_ref
,
2378 affected_refnames
, err
);
2383 ret
= lock_raw_ref(refs
, update
->refname
, mustexist
,
2384 affected_refnames
, NULL
,
2386 &update
->type
, err
);
2390 reason
= strbuf_detach(err
, NULL
);
2391 strbuf_addf(err
, "cannot lock ref '%s': %s",
2392 original_update_refname(update
), reason
);
2397 update
->backend_data
= lock
;
2399 if (update
->type
& REF_ISSYMREF
) {
2400 if (update
->flags
& REF_NO_DEREF
) {
2402 * We won't be reading the referent as part of
2403 * the transaction, so we have to read it here
2404 * to record and possibly check old_oid:
2406 if (refs_read_ref_full(&refs
->base
,
2408 &lock
->old_oid
, NULL
)) {
2409 if (update
->flags
& REF_HAVE_OLD
) {
2410 strbuf_addf(err
, "cannot lock ref '%s': "
2411 "error reading reference",
2412 original_update_refname(update
));
2413 ret
= TRANSACTION_GENERIC_ERROR
;
2416 } else if (check_old_oid(update
, &lock
->old_oid
, err
)) {
2417 ret
= TRANSACTION_GENERIC_ERROR
;
2422 * Create a new update for the reference this
2423 * symref is pointing at. Also, we will record
2424 * and verify old_oid for this update as part
2425 * of processing the split-off update, so we
2426 * don't have to do it here.
2428 ret
= split_symref_update(refs
, update
,
2429 referent
.buf
, transaction
,
2430 affected_refnames
, err
);
2435 struct ref_update
*parent_update
;
2437 if (check_old_oid(update
, &lock
->old_oid
, err
)) {
2438 ret
= TRANSACTION_GENERIC_ERROR
;
2443 * If this update is happening indirectly because of a
2444 * symref update, record the old OID in the parent
2447 for (parent_update
= update
->parent_update
;
2449 parent_update
= parent_update
->parent_update
) {
2450 struct ref_lock
*parent_lock
= parent_update
->backend_data
;
2451 oidcpy(&parent_lock
->old_oid
, &lock
->old_oid
);
2455 if ((update
->flags
& REF_HAVE_NEW
) &&
2456 !(update
->flags
& REF_DELETING
) &&
2457 !(update
->flags
& REF_LOG_ONLY
)) {
2458 if (!(update
->type
& REF_ISSYMREF
) &&
2459 !oidcmp(&lock
->old_oid
, &update
->new_oid
)) {
2461 * The reference already has the desired
2462 * value, so we don't need to write it.
2464 } else if (write_ref_to_lockfile(lock
, &update
->new_oid
,
2466 char *write_err
= strbuf_detach(err
, NULL
);
2469 * The lock was freed upon failure of
2470 * write_ref_to_lockfile():
2472 update
->backend_data
= NULL
;
2474 "cannot update ref '%s': %s",
2475 update
->refname
, write_err
);
2477 ret
= TRANSACTION_GENERIC_ERROR
;
2480 update
->flags
|= REF_NEEDS_COMMIT
;
2483 if (!(update
->flags
& REF_NEEDS_COMMIT
)) {
2485 * We didn't call write_ref_to_lockfile(), so
2486 * the lockfile is still open. Close it to
2487 * free up the file descriptor:
2489 if (close_ref_gently(lock
)) {
2490 strbuf_addf(err
, "couldn't close '%s.lock'",
2492 ret
= TRANSACTION_GENERIC_ERROR
;
2498 strbuf_release(&referent
);
2502 struct files_transaction_backend_data
{
2503 struct ref_transaction
*packed_transaction
;
2504 int packed_refs_locked
;
2508 * Unlock any references in `transaction` that are still locked, and
2509 * mark the transaction closed.
2511 static void files_transaction_cleanup(struct files_ref_store
*refs
,
2512 struct ref_transaction
*transaction
)
2515 struct files_transaction_backend_data
*backend_data
=
2516 transaction
->backend_data
;
2517 struct strbuf err
= STRBUF_INIT
;
2519 for (i
= 0; i
< transaction
->nr
; i
++) {
2520 struct ref_update
*update
= transaction
->updates
[i
];
2521 struct ref_lock
*lock
= update
->backend_data
;
2525 update
->backend_data
= NULL
;
2529 if (backend_data
->packed_transaction
&&
2530 ref_transaction_abort(backend_data
->packed_transaction
, &err
)) {
2531 error("error aborting transaction: %s", err
.buf
);
2532 strbuf_release(&err
);
2535 if (backend_data
->packed_refs_locked
)
2536 packed_refs_unlock(refs
->packed_ref_store
);
2540 transaction
->state
= REF_TRANSACTION_CLOSED
;
2543 static int files_transaction_prepare(struct ref_store
*ref_store
,
2544 struct ref_transaction
*transaction
,
2547 struct files_ref_store
*refs
=
2548 files_downcast(ref_store
, REF_STORE_WRITE
,
2549 "ref_transaction_prepare");
2552 struct string_list affected_refnames
= STRING_LIST_INIT_NODUP
;
2553 char *head_ref
= NULL
;
2555 struct files_transaction_backend_data
*backend_data
;
2556 struct ref_transaction
*packed_transaction
= NULL
;
2560 if (!transaction
->nr
)
2563 backend_data
= xcalloc(1, sizeof(*backend_data
));
2564 transaction
->backend_data
= backend_data
;
2567 * Fail if a refname appears more than once in the
2568 * transaction. (If we end up splitting up any updates using
2569 * split_symref_update() or split_head_update(), those
2570 * functions will check that the new updates don't have the
2571 * same refname as any existing ones.) Also fail if any of the
2572 * updates use REF_IS_PRUNING without REF_NO_DEREF.
2574 for (i
= 0; i
< transaction
->nr
; i
++) {
2575 struct ref_update
*update
= transaction
->updates
[i
];
2576 struct string_list_item
*item
=
2577 string_list_append(&affected_refnames
, update
->refname
);
2579 if ((update
->flags
& REF_IS_PRUNING
) &&
2580 !(update
->flags
& REF_NO_DEREF
))
2581 BUG("REF_IS_PRUNING set without REF_NO_DEREF");
2584 * We store a pointer to update in item->util, but at
2585 * the moment we never use the value of this field
2586 * except to check whether it is non-NULL.
2588 item
->util
= update
;
2590 string_list_sort(&affected_refnames
);
2591 if (ref_update_reject_duplicates(&affected_refnames
, err
)) {
2592 ret
= TRANSACTION_GENERIC_ERROR
;
2597 * Special hack: If a branch is updated directly and HEAD
2598 * points to it (may happen on the remote side of a push
2599 * for example) then logically the HEAD reflog should be
2602 * A generic solution would require reverse symref lookups,
2603 * but finding all symrefs pointing to a given branch would be
2604 * rather costly for this rare event (the direct update of a
2605 * branch) to be worth it. So let's cheat and check with HEAD
2606 * only, which should cover 99% of all usage scenarios (even
2607 * 100% of the default ones).
2609 * So if HEAD is a symbolic reference, then record the name of
2610 * the reference that it points to. If we see an update of
2611 * head_ref within the transaction, then split_head_update()
2612 * arranges for the reflog of HEAD to be updated, too.
2614 head_ref
= refs_resolve_refdup(ref_store
, "HEAD",
2615 RESOLVE_REF_NO_RECURSE
,
2618 if (head_ref
&& !(head_type
& REF_ISSYMREF
)) {
2619 FREE_AND_NULL(head_ref
);
2623 * Acquire all locks, verify old values if provided, check
2624 * that new values are valid, and write new values to the
2625 * lockfiles, ready to be activated. Only keep one lockfile
2626 * open at a time to avoid running out of file descriptors.
2627 * Note that lock_ref_for_update() might append more updates
2628 * to the transaction.
2630 for (i
= 0; i
< transaction
->nr
; i
++) {
2631 struct ref_update
*update
= transaction
->updates
[i
];
2633 ret
= lock_ref_for_update(refs
, update
, transaction
,
2634 head_ref
, &affected_refnames
, err
);
2638 if (update
->flags
& REF_DELETING
&&
2639 !(update
->flags
& REF_LOG_ONLY
) &&
2640 !(update
->flags
& REF_IS_PRUNING
)) {
2642 * This reference has to be deleted from
2643 * packed-refs if it exists there.
2645 if (!packed_transaction
) {
2646 packed_transaction
= ref_store_transaction_begin(
2647 refs
->packed_ref_store
, err
);
2648 if (!packed_transaction
) {
2649 ret
= TRANSACTION_GENERIC_ERROR
;
2653 backend_data
->packed_transaction
=
2657 ref_transaction_add_update(
2658 packed_transaction
, update
->refname
,
2659 REF_HAVE_NEW
| REF_NO_DEREF
,
2660 &update
->new_oid
, NULL
,
2665 if (packed_transaction
) {
2666 if (packed_refs_lock(refs
->packed_ref_store
, 0, err
)) {
2667 ret
= TRANSACTION_GENERIC_ERROR
;
2670 backend_data
->packed_refs_locked
= 1;
2672 if (is_packed_transaction_needed(refs
->packed_ref_store
,
2673 packed_transaction
)) {
2674 ret
= ref_transaction_prepare(packed_transaction
, err
);
2677 * We can skip rewriting the `packed-refs`
2678 * file. But we do need to leave it locked, so
2679 * that somebody else doesn't pack a reference
2680 * that we are trying to delete.
2682 if (ref_transaction_abort(packed_transaction
, err
)) {
2683 ret
= TRANSACTION_GENERIC_ERROR
;
2686 backend_data
->packed_transaction
= NULL
;
2692 string_list_clear(&affected_refnames
, 0);
2695 files_transaction_cleanup(refs
, transaction
);
2697 transaction
->state
= REF_TRANSACTION_PREPARED
;
2702 static int files_transaction_finish(struct ref_store
*ref_store
,
2703 struct ref_transaction
*transaction
,
2706 struct files_ref_store
*refs
=
2707 files_downcast(ref_store
, 0, "ref_transaction_finish");
2710 struct strbuf sb
= STRBUF_INIT
;
2711 struct files_transaction_backend_data
*backend_data
;
2712 struct ref_transaction
*packed_transaction
;
2717 if (!transaction
->nr
) {
2718 transaction
->state
= REF_TRANSACTION_CLOSED
;
2722 backend_data
= transaction
->backend_data
;
2723 packed_transaction
= backend_data
->packed_transaction
;
2725 /* Perform updates first so live commits remain referenced */
2726 for (i
= 0; i
< transaction
->nr
; i
++) {
2727 struct ref_update
*update
= transaction
->updates
[i
];
2728 struct ref_lock
*lock
= update
->backend_data
;
2730 if (update
->flags
& REF_NEEDS_COMMIT
||
2731 update
->flags
& REF_LOG_ONLY
) {
2732 if (files_log_ref_write(refs
,
2736 update
->msg
, update
->flags
,
2738 char *old_msg
= strbuf_detach(err
, NULL
);
2740 strbuf_addf(err
, "cannot update the ref '%s': %s",
2741 lock
->ref_name
, old_msg
);
2744 update
->backend_data
= NULL
;
2745 ret
= TRANSACTION_GENERIC_ERROR
;
2749 if (update
->flags
& REF_NEEDS_COMMIT
) {
2750 clear_loose_ref_cache(refs
);
2751 if (commit_ref(lock
)) {
2752 strbuf_addf(err
, "couldn't set '%s'", lock
->ref_name
);
2754 update
->backend_data
= NULL
;
2755 ret
= TRANSACTION_GENERIC_ERROR
;
2762 * Now that updates are safely completed, we can perform
2763 * deletes. First delete the reflogs of any references that
2764 * will be deleted, since (in the unexpected event of an
2765 * error) leaving a reference without a reflog is less bad
2766 * than leaving a reflog without a reference (the latter is a
2767 * mildly invalid repository state):
2769 for (i
= 0; i
< transaction
->nr
; i
++) {
2770 struct ref_update
*update
= transaction
->updates
[i
];
2771 if (update
->flags
& REF_DELETING
&&
2772 !(update
->flags
& REF_LOG_ONLY
) &&
2773 !(update
->flags
& REF_IS_PRUNING
)) {
2775 files_reflog_path(refs
, &sb
, update
->refname
);
2776 if (!unlink_or_warn(sb
.buf
))
2777 try_remove_empty_parents(refs
, update
->refname
,
2778 REMOVE_EMPTY_PARENTS_REFLOG
);
2783 * Perform deletes now that updates are safely completed.
2785 * First delete any packed versions of the references, while
2786 * retaining the packed-refs lock:
2788 if (packed_transaction
) {
2789 ret
= ref_transaction_commit(packed_transaction
, err
);
2790 ref_transaction_free(packed_transaction
);
2791 packed_transaction
= NULL
;
2792 backend_data
->packed_transaction
= NULL
;
2797 /* Now delete the loose versions of the references: */
2798 for (i
= 0; i
< transaction
->nr
; i
++) {
2799 struct ref_update
*update
= transaction
->updates
[i
];
2800 struct ref_lock
*lock
= update
->backend_data
;
2802 if (update
->flags
& REF_DELETING
&&
2803 !(update
->flags
& REF_LOG_ONLY
)) {
2804 if (!(update
->type
& REF_ISPACKED
) ||
2805 update
->type
& REF_ISSYMREF
) {
2806 /* It is a loose reference. */
2808 files_ref_path(refs
, &sb
, lock
->ref_name
);
2809 if (unlink_or_msg(sb
.buf
, err
)) {
2810 ret
= TRANSACTION_GENERIC_ERROR
;
2813 update
->flags
|= REF_DELETED_LOOSE
;
2818 clear_loose_ref_cache(refs
);
2821 files_transaction_cleanup(refs
, transaction
);
2823 for (i
= 0; i
< transaction
->nr
; i
++) {
2824 struct ref_update
*update
= transaction
->updates
[i
];
2826 if (update
->flags
& REF_DELETED_LOOSE
) {
2828 * The loose reference was deleted. Delete any
2829 * empty parent directories. (Note that this
2830 * can only work because we have already
2831 * removed the lockfile.)
2833 try_remove_empty_parents(refs
, update
->refname
,
2834 REMOVE_EMPTY_PARENTS_REF
);
2838 strbuf_release(&sb
);
2842 static int files_transaction_abort(struct ref_store
*ref_store
,
2843 struct ref_transaction
*transaction
,
2846 struct files_ref_store
*refs
=
2847 files_downcast(ref_store
, 0, "ref_transaction_abort");
2849 files_transaction_cleanup(refs
, transaction
);
2853 static int ref_present(const char *refname
,
2854 const struct object_id
*oid
, int flags
, void *cb_data
)
2856 struct string_list
*affected_refnames
= cb_data
;
2858 return string_list_has_string(affected_refnames
, refname
);
2861 static int files_initial_transaction_commit(struct ref_store
*ref_store
,
2862 struct ref_transaction
*transaction
,
2865 struct files_ref_store
*refs
=
2866 files_downcast(ref_store
, REF_STORE_WRITE
,
2867 "initial_ref_transaction_commit");
2870 struct string_list affected_refnames
= STRING_LIST_INIT_NODUP
;
2871 struct ref_transaction
*packed_transaction
= NULL
;
2875 if (transaction
->state
!= REF_TRANSACTION_OPEN
)
2876 BUG("commit called for transaction that is not open");
2878 /* Fail if a refname appears more than once in the transaction: */
2879 for (i
= 0; i
< transaction
->nr
; i
++)
2880 string_list_append(&affected_refnames
,
2881 transaction
->updates
[i
]->refname
);
2882 string_list_sort(&affected_refnames
);
2883 if (ref_update_reject_duplicates(&affected_refnames
, err
)) {
2884 ret
= TRANSACTION_GENERIC_ERROR
;
2889 * It's really undefined to call this function in an active
2890 * repository or when there are existing references: we are
2891 * only locking and changing packed-refs, so (1) any
2892 * simultaneous processes might try to change a reference at
2893 * the same time we do, and (2) any existing loose versions of
2894 * the references that we are setting would have precedence
2895 * over our values. But some remote helpers create the remote
2896 * "HEAD" and "master" branches before calling this function,
2897 * so here we really only check that none of the references
2898 * that we are creating already exists.
2900 if (refs_for_each_rawref(&refs
->base
, ref_present
,
2901 &affected_refnames
))
2902 BUG("initial ref transaction called with existing refs");
2904 packed_transaction
= ref_store_transaction_begin(refs
->packed_ref_store
, err
);
2905 if (!packed_transaction
) {
2906 ret
= TRANSACTION_GENERIC_ERROR
;
2910 for (i
= 0; i
< transaction
->nr
; i
++) {
2911 struct ref_update
*update
= transaction
->updates
[i
];
2913 if ((update
->flags
& REF_HAVE_OLD
) &&
2914 !is_null_oid(&update
->old_oid
))
2915 BUG("initial ref transaction with old_sha1 set");
2916 if (refs_verify_refname_available(&refs
->base
, update
->refname
,
2917 &affected_refnames
, NULL
,
2919 ret
= TRANSACTION_NAME_CONFLICT
;
2924 * Add a reference creation for this reference to the
2925 * packed-refs transaction:
2927 ref_transaction_add_update(packed_transaction
, update
->refname
,
2928 update
->flags
& ~REF_HAVE_OLD
,
2929 &update
->new_oid
, &update
->old_oid
,
2933 if (packed_refs_lock(refs
->packed_ref_store
, 0, err
)) {
2934 ret
= TRANSACTION_GENERIC_ERROR
;
2938 if (initial_ref_transaction_commit(packed_transaction
, err
)) {
2939 ret
= TRANSACTION_GENERIC_ERROR
;
2942 packed_refs_unlock(refs
->packed_ref_store
);
2944 if (packed_transaction
)
2945 ref_transaction_free(packed_transaction
);
2946 transaction
->state
= REF_TRANSACTION_CLOSED
;
2947 string_list_clear(&affected_refnames
, 0);
2951 struct expire_reflog_cb
{
2953 reflog_expiry_should_prune_fn
*should_prune_fn
;
2956 struct object_id last_kept_oid
;
2959 static int expire_reflog_ent(struct object_id
*ooid
, struct object_id
*noid
,
2960 const char *email
, timestamp_t timestamp
, int tz
,
2961 const char *message
, void *cb_data
)
2963 struct expire_reflog_cb
*cb
= cb_data
;
2964 struct expire_reflog_policy_cb
*policy_cb
= cb
->policy_cb
;
2966 if (cb
->flags
& EXPIRE_REFLOGS_REWRITE
)
2967 ooid
= &cb
->last_kept_oid
;
2969 if ((*cb
->should_prune_fn
)(ooid
, noid
, email
, timestamp
, tz
,
2970 message
, policy_cb
)) {
2972 printf("would prune %s", message
);
2973 else if (cb
->flags
& EXPIRE_REFLOGS_VERBOSE
)
2974 printf("prune %s", message
);
2977 fprintf(cb
->newlog
, "%s %s %s %"PRItime
" %+05d\t%s",
2978 oid_to_hex(ooid
), oid_to_hex(noid
),
2979 email
, timestamp
, tz
, message
);
2980 oidcpy(&cb
->last_kept_oid
, noid
);
2982 if (cb
->flags
& EXPIRE_REFLOGS_VERBOSE
)
2983 printf("keep %s", message
);
2988 static int files_reflog_expire(struct ref_store
*ref_store
,
2989 const char *refname
, const struct object_id
*oid
,
2991 reflog_expiry_prepare_fn prepare_fn
,
2992 reflog_expiry_should_prune_fn should_prune_fn
,
2993 reflog_expiry_cleanup_fn cleanup_fn
,
2994 void *policy_cb_data
)
2996 struct files_ref_store
*refs
=
2997 files_downcast(ref_store
, REF_STORE_WRITE
, "reflog_expire");
2998 static struct lock_file reflog_lock
;
2999 struct expire_reflog_cb cb
;
3000 struct ref_lock
*lock
;
3001 struct strbuf log_file_sb
= STRBUF_INIT
;
3005 struct strbuf err
= STRBUF_INIT
;
3007 memset(&cb
, 0, sizeof(cb
));
3009 cb
.policy_cb
= policy_cb_data
;
3010 cb
.should_prune_fn
= should_prune_fn
;
3013 * The reflog file is locked by holding the lock on the
3014 * reference itself, plus we might need to update the
3015 * reference if --updateref was specified:
3017 lock
= lock_ref_oid_basic(refs
, refname
, oid
,
3018 NULL
, NULL
, REF_NO_DEREF
,
3021 error("cannot lock ref '%s': %s", refname
, err
.buf
);
3022 strbuf_release(&err
);
3025 if (!refs_reflog_exists(ref_store
, refname
)) {
3030 files_reflog_path(refs
, &log_file_sb
, refname
);
3031 log_file
= strbuf_detach(&log_file_sb
, NULL
);
3032 if (!(flags
& EXPIRE_REFLOGS_DRY_RUN
)) {
3034 * Even though holding $GIT_DIR/logs/$reflog.lock has
3035 * no locking implications, we use the lock_file
3036 * machinery here anyway because it does a lot of the
3037 * work we need, including cleaning up if the program
3038 * exits unexpectedly.
3040 if (hold_lock_file_for_update(&reflog_lock
, log_file
, 0) < 0) {
3041 struct strbuf err
= STRBUF_INIT
;
3042 unable_to_lock_message(log_file
, errno
, &err
);
3043 error("%s", err
.buf
);
3044 strbuf_release(&err
);
3047 cb
.newlog
= fdopen_lock_file(&reflog_lock
, "w");
3049 error("cannot fdopen %s (%s)",
3050 get_lock_file_path(&reflog_lock
), strerror(errno
));
3055 (*prepare_fn
)(refname
, oid
, cb
.policy_cb
);
3056 refs_for_each_reflog_ent(ref_store
, refname
, expire_reflog_ent
, &cb
);
3057 (*cleanup_fn
)(cb
.policy_cb
);
3059 if (!(flags
& EXPIRE_REFLOGS_DRY_RUN
)) {
3061 * It doesn't make sense to adjust a reference pointed
3062 * to by a symbolic ref based on expiring entries in
3063 * the symbolic reference's reflog. Nor can we update
3064 * a reference if there are no remaining reflog
3067 int update
= (flags
& EXPIRE_REFLOGS_UPDATE_REF
) &&
3068 !(type
& REF_ISSYMREF
) &&
3069 !is_null_oid(&cb
.last_kept_oid
);
3071 if (close_lock_file_gently(&reflog_lock
)) {
3072 status
|= error("couldn't write %s: %s", log_file
,
3074 rollback_lock_file(&reflog_lock
);
3075 } else if (update
&&
3076 (write_in_full(get_lock_file_fd(&lock
->lk
),
3077 oid_to_hex(&cb
.last_kept_oid
), GIT_SHA1_HEXSZ
) < 0 ||
3078 write_str_in_full(get_lock_file_fd(&lock
->lk
), "\n") < 0 ||
3079 close_ref_gently(lock
) < 0)) {
3080 status
|= error("couldn't write %s",
3081 get_lock_file_path(&lock
->lk
));
3082 rollback_lock_file(&reflog_lock
);
3083 } else if (commit_lock_file(&reflog_lock
)) {
3084 status
|= error("unable to write reflog '%s' (%s)",
3085 log_file
, strerror(errno
));
3086 } else if (update
&& commit_ref(lock
)) {
3087 status
|= error("couldn't set %s", lock
->ref_name
);
3095 rollback_lock_file(&reflog_lock
);
3101 static int files_init_db(struct ref_store
*ref_store
, struct strbuf
*err
)
3103 struct files_ref_store
*refs
=
3104 files_downcast(ref_store
, REF_STORE_WRITE
, "init_db");
3105 struct strbuf sb
= STRBUF_INIT
;
3108 * Create .git/refs/{heads,tags}
3110 files_ref_path(refs
, &sb
, "refs/heads");
3111 safe_create_dir(sb
.buf
, 1);
3114 files_ref_path(refs
, &sb
, "refs/tags");
3115 safe_create_dir(sb
.buf
, 1);
3117 strbuf_release(&sb
);
3121 struct ref_storage_be refs_be_files
= {
3124 files_ref_store_create
,
3126 files_transaction_prepare
,
3127 files_transaction_finish
,
3128 files_transaction_abort
,
3129 files_initial_transaction_commit
,
3132 files_create_symref
,
3137 files_ref_iterator_begin
,
3140 files_reflog_iterator_begin
,
3141 files_for_each_reflog_ent
,
3142 files_for_each_reflog_ent_reverse
,
3143 files_reflog_exists
,
3144 files_create_reflog
,
3145 files_delete_reflog
,