3 #include "refs-internal.h"
4 #include "../iterator.h"
5 #include "../dir-iterator.h"
6 #include "../lockfile.h"
13 struct object_id old_oid
;
19 * Information used (along with the information in ref_entry) to
20 * describe a single cached reference. This data structure only
21 * occurs embedded in a union in struct ref_entry, and only when
22 * (ref_entry->flag & REF_DIR) is zero.
26 * The name of the object to which this reference resolves
27 * (which may be a tag object). If REF_ISBROKEN, this is
28 * null. If REF_ISSYMREF, then this is the name of the object
29 * referred to by the last reference in the symlink chain.
34 * If REF_KNOWS_PEELED, then this field holds the peeled value
35 * of this reference, or null if the reference is known not to
36 * be peelable. See the documentation for peel_ref() for an
37 * exact definition of "peelable".
39 struct object_id peeled
;
42 struct files_ref_store
;
45 * Information used (along with the information in ref_entry) to
46 * describe a level in the hierarchy of references. This data
47 * structure only occurs embedded in a union in struct ref_entry, and
48 * only when (ref_entry.flag & REF_DIR) is set. In that case,
49 * (ref_entry.flag & REF_INCOMPLETE) determines whether the references
50 * in the directory have already been read:
52 * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose
53 * or packed references, already read.
55 * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose
56 * references that hasn't been read yet (nor has any of its
59 * Entries within a directory are stored within a growable array of
60 * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i <
61 * sorted are sorted by their component name in strcmp() order and the
62 * remaining entries are unsorted.
64 * Loose references are read lazily, one directory at a time. When a
65 * directory of loose references is read, then all of the references
66 * in that directory are stored, and REF_INCOMPLETE stubs are created
67 * for any subdirectories, but the subdirectories themselves are not
68 * read. The reading is triggered by get_ref_dir().
74 * Entries with index 0 <= i < sorted are sorted by name. New
75 * entries are appended to the list unsorted, and are sorted
76 * only when required; thus we avoid the need to sort the list
77 * after the addition of every reference.
81 /* A pointer to the files_ref_store that contains this ref_dir. */
82 struct files_ref_store
*ref_store
;
84 struct ref_entry
**entries
;
88 * Bit values for ref_entry::flag. REF_ISSYMREF=0x01,
89 * REF_ISPACKED=0x02, REF_ISBROKEN=0x04 and REF_BAD_NAME=0x08 are
90 * public values; see refs.h.
94 * The field ref_entry->u.value.peeled of this value entry contains
95 * the correct peeled value for the reference, which might be
96 * null_sha1 if the reference is not a tag or if it is broken.
98 #define REF_KNOWS_PEELED 0x10
100 /* ref_entry represents a directory of references */
104 * Entry has not yet been read from disk (used only for REF_DIR
105 * entries representing loose references)
107 #define REF_INCOMPLETE 0x40
110 * A ref_entry represents either a reference or a "subdirectory" of
113 * Each directory in the reference namespace is represented by a
114 * ref_entry with (flags & REF_DIR) set and containing a subdir member
115 * that holds the entries in that directory that have been read so
116 * far. If (flags & REF_INCOMPLETE) is set, then the directory and
117 * its subdirectories haven't been read yet. REF_INCOMPLETE is only
118 * used for loose reference directories.
120 * References are represented by a ref_entry with (flags & REF_DIR)
121 * unset and a value member that describes the reference's value. The
122 * flag member is at the ref_entry level, but it is also needed to
123 * interpret the contents of the value field (in other words, a
124 * ref_value object is not very much use without the enclosing
127 * Reference names cannot end with slash and directories' names are
128 * always stored with a trailing slash (except for the top-level
129 * directory, which is always denoted by ""). This has two nice
130 * consequences: (1) when the entries in each subdir are sorted
131 * lexicographically by name (as they usually are), the references in
132 * a whole tree can be generated in lexicographic order by traversing
133 * the tree in left-to-right, depth-first order; (2) the names of
134 * references and subdirectories cannot conflict, and therefore the
135 * presence of an empty subdirectory does not block the creation of a
136 * similarly-named reference. (The fact that reference names with the
137 * same leading components can conflict *with each other* is a
138 * separate issue that is regulated by verify_refname_available().)
140 * Please note that the name field contains the fully-qualified
141 * reference (or subdirectory) name. Space could be saved by only
142 * storing the relative names. But that would require the full names
143 * to be generated on the fly when iterating in do_for_each_ref(), and
144 * would break callback functions, who have always been able to assume
145 * that the name strings that they are passed will not be freed during
149 unsigned char flag
; /* ISSYMREF? ISPACKED? */
151 struct ref_value value
; /* if not (flags&REF_DIR) */
152 struct ref_dir subdir
; /* if (flags&REF_DIR) */
155 * The full name of the reference (e.g., "refs/heads/master")
156 * or the full name of the directory with a trailing slash
157 * (e.g., "refs/heads/"):
159 char name
[FLEX_ARRAY
];
162 static void read_loose_refs(const char *dirname
, struct ref_dir
*dir
);
163 static int search_ref_dir(struct ref_dir
*dir
, const char *refname
, size_t len
);
164 static struct ref_entry
*create_dir_entry(struct files_ref_store
*ref_store
,
165 const char *dirname
, size_t len
,
167 static void add_entry_to_dir(struct ref_dir
*dir
, struct ref_entry
*entry
);
169 static struct ref_dir
*get_ref_dir(struct ref_entry
*entry
)
172 assert(entry
->flag
& REF_DIR
);
173 dir
= &entry
->u
.subdir
;
174 if (entry
->flag
& REF_INCOMPLETE
) {
175 read_loose_refs(entry
->name
, dir
);
178 * Manually add refs/bisect, which, being
179 * per-worktree, might not appear in the directory
180 * listing for refs/ in the main repo.
182 if (!strcmp(entry
->name
, "refs/")) {
183 int pos
= search_ref_dir(dir
, "refs/bisect/", 12);
185 struct ref_entry
*child_entry
;
186 child_entry
= create_dir_entry(dir
->ref_store
,
189 add_entry_to_dir(dir
, child_entry
);
190 read_loose_refs("refs/bisect",
191 &child_entry
->u
.subdir
);
194 entry
->flag
&= ~REF_INCOMPLETE
;
199 static struct ref_entry
*create_ref_entry(const char *refname
,
200 const unsigned char *sha1
, int flag
,
203 struct ref_entry
*ref
;
206 check_refname_format(refname
, REFNAME_ALLOW_ONELEVEL
))
207 die("Reference has invalid format: '%s'", refname
);
208 FLEX_ALLOC_STR(ref
, name
, refname
);
209 hashcpy(ref
->u
.value
.oid
.hash
, sha1
);
210 oidclr(&ref
->u
.value
.peeled
);
215 static void clear_ref_dir(struct ref_dir
*dir
);
217 static void free_ref_entry(struct ref_entry
*entry
)
219 if (entry
->flag
& REF_DIR
) {
221 * Do not use get_ref_dir() here, as that might
222 * trigger the reading of loose refs.
224 clear_ref_dir(&entry
->u
.subdir
);
230 * Add a ref_entry to the end of dir (unsorted). Entry is always
231 * stored directly in dir; no recursion into subdirectories is
234 static void add_entry_to_dir(struct ref_dir
*dir
, struct ref_entry
*entry
)
236 ALLOC_GROW(dir
->entries
, dir
->nr
+ 1, dir
->alloc
);
237 dir
->entries
[dir
->nr
++] = entry
;
238 /* optimize for the case that entries are added in order */
240 (dir
->nr
== dir
->sorted
+ 1 &&
241 strcmp(dir
->entries
[dir
->nr
- 2]->name
,
242 dir
->entries
[dir
->nr
- 1]->name
) < 0))
243 dir
->sorted
= dir
->nr
;
247 * Clear and free all entries in dir, recursively.
249 static void clear_ref_dir(struct ref_dir
*dir
)
252 for (i
= 0; i
< dir
->nr
; i
++)
253 free_ref_entry(dir
->entries
[i
]);
255 dir
->sorted
= dir
->nr
= dir
->alloc
= 0;
260 * Create a struct ref_entry object for the specified dirname.
261 * dirname is the name of the directory with a trailing slash (e.g.,
262 * "refs/heads/") or "" for the top-level directory.
264 static struct ref_entry
*create_dir_entry(struct files_ref_store
*ref_store
,
265 const char *dirname
, size_t len
,
268 struct ref_entry
*direntry
;
269 FLEX_ALLOC_MEM(direntry
, name
, dirname
, len
);
270 direntry
->u
.subdir
.ref_store
= ref_store
;
271 direntry
->flag
= REF_DIR
| (incomplete
? REF_INCOMPLETE
: 0);
275 static int ref_entry_cmp(const void *a
, const void *b
)
277 struct ref_entry
*one
= *(struct ref_entry
**)a
;
278 struct ref_entry
*two
= *(struct ref_entry
**)b
;
279 return strcmp(one
->name
, two
->name
);
282 static void sort_ref_dir(struct ref_dir
*dir
);
284 struct string_slice
{
289 static int ref_entry_cmp_sslice(const void *key_
, const void *ent_
)
291 const struct string_slice
*key
= key_
;
292 const struct ref_entry
*ent
= *(const struct ref_entry
* const *)ent_
;
293 int cmp
= strncmp(key
->str
, ent
->name
, key
->len
);
296 return '\0' - (unsigned char)ent
->name
[key
->len
];
300 * Return the index of the entry with the given refname from the
301 * ref_dir (non-recursively), sorting dir if necessary. Return -1 if
302 * no such entry is found. dir must already be complete.
304 static int search_ref_dir(struct ref_dir
*dir
, const char *refname
, size_t len
)
306 struct ref_entry
**r
;
307 struct string_slice key
;
309 if (refname
== NULL
|| !dir
->nr
)
315 r
= bsearch(&key
, dir
->entries
, dir
->nr
, sizeof(*dir
->entries
),
316 ref_entry_cmp_sslice
);
321 return r
- dir
->entries
;
325 * Search for a directory entry directly within dir (without
326 * recursing). Sort dir if necessary. subdirname must be a directory
327 * name (i.e., end in '/'). If mkdir is set, then create the
328 * directory if it is missing; otherwise, return NULL if the desired
329 * directory cannot be found. dir must already be complete.
331 static struct ref_dir
*search_for_subdir(struct ref_dir
*dir
,
332 const char *subdirname
, size_t len
,
335 int entry_index
= search_ref_dir(dir
, subdirname
, len
);
336 struct ref_entry
*entry
;
337 if (entry_index
== -1) {
341 * Since dir is complete, the absence of a subdir
342 * means that the subdir really doesn't exist;
343 * therefore, create an empty record for it but mark
344 * the record complete.
346 entry
= create_dir_entry(dir
->ref_store
, subdirname
, len
, 0);
347 add_entry_to_dir(dir
, entry
);
349 entry
= dir
->entries
[entry_index
];
351 return get_ref_dir(entry
);
355 * If refname is a reference name, find the ref_dir within the dir
356 * tree that should hold refname. If refname is a directory name
357 * (i.e., ends in '/'), then return that ref_dir itself. dir must
358 * represent the top-level directory and must already be complete.
359 * Sort ref_dirs and recurse into subdirectories as necessary. If
360 * mkdir is set, then create any missing directories; otherwise,
361 * return NULL if the desired directory cannot be found.
363 static struct ref_dir
*find_containing_dir(struct ref_dir
*dir
,
364 const char *refname
, int mkdir
)
367 for (slash
= strchr(refname
, '/'); slash
; slash
= strchr(slash
+ 1, '/')) {
368 size_t dirnamelen
= slash
- refname
+ 1;
369 struct ref_dir
*subdir
;
370 subdir
= search_for_subdir(dir
, refname
, dirnamelen
, mkdir
);
382 * Find the value entry with the given name in dir, sorting ref_dirs
383 * and recursing into subdirectories as necessary. If the name is not
384 * found or it corresponds to a directory entry, return NULL.
386 static struct ref_entry
*find_ref(struct ref_dir
*dir
, const char *refname
)
389 struct ref_entry
*entry
;
390 dir
= find_containing_dir(dir
, refname
, 0);
393 entry_index
= search_ref_dir(dir
, refname
, strlen(refname
));
394 if (entry_index
== -1)
396 entry
= dir
->entries
[entry_index
];
397 return (entry
->flag
& REF_DIR
) ? NULL
: entry
;
401 * Remove the entry with the given name from dir, recursing into
402 * subdirectories as necessary. If refname is the name of a directory
403 * (i.e., ends with '/'), then remove the directory and its contents.
404 * If the removal was successful, return the number of entries
405 * remaining in the directory entry that contained the deleted entry.
406 * If the name was not found, return -1. Please note that this
407 * function only deletes the entry from the cache; it does not delete
408 * it from the filesystem or ensure that other cache entries (which
409 * might be symbolic references to the removed entry) are updated.
410 * Nor does it remove any containing dir entries that might be made
411 * empty by the removal. dir must represent the top-level directory
412 * and must already be complete.
414 static int remove_entry(struct ref_dir
*dir
, const char *refname
)
416 int refname_len
= strlen(refname
);
418 struct ref_entry
*entry
;
419 int is_dir
= refname
[refname_len
- 1] == '/';
422 * refname represents a reference directory. Remove
423 * the trailing slash; otherwise we will get the
424 * directory *representing* refname rather than the
425 * one *containing* it.
427 char *dirname
= xmemdupz(refname
, refname_len
- 1);
428 dir
= find_containing_dir(dir
, dirname
, 0);
431 dir
= find_containing_dir(dir
, refname
, 0);
435 entry_index
= search_ref_dir(dir
, refname
, refname_len
);
436 if (entry_index
== -1)
438 entry
= dir
->entries
[entry_index
];
440 memmove(&dir
->entries
[entry_index
],
441 &dir
->entries
[entry_index
+ 1],
442 (dir
->nr
- entry_index
- 1) * sizeof(*dir
->entries
)
445 if (dir
->sorted
> entry_index
)
447 free_ref_entry(entry
);
452 * Add a ref_entry to the ref_dir (unsorted), recursing into
453 * subdirectories as necessary. dir must represent the top-level
454 * directory. Return 0 on success.
456 static int add_ref(struct ref_dir
*dir
, struct ref_entry
*ref
)
458 dir
= find_containing_dir(dir
, ref
->name
, 1);
461 add_entry_to_dir(dir
, ref
);
466 * Emit a warning and return true iff ref1 and ref2 have the same name
467 * and the same sha1. Die if they have the same name but different
470 static int is_dup_ref(const struct ref_entry
*ref1
, const struct ref_entry
*ref2
)
472 if (strcmp(ref1
->name
, ref2
->name
))
475 /* Duplicate name; make sure that they don't conflict: */
477 if ((ref1
->flag
& REF_DIR
) || (ref2
->flag
& REF_DIR
))
478 /* This is impossible by construction */
479 die("Reference directory conflict: %s", ref1
->name
);
481 if (oidcmp(&ref1
->u
.value
.oid
, &ref2
->u
.value
.oid
))
482 die("Duplicated ref, and SHA1s don't match: %s", ref1
->name
);
484 warning("Duplicated ref: %s", ref1
->name
);
489 * Sort the entries in dir non-recursively (if they are not already
490 * sorted) and remove any duplicate entries.
492 static void sort_ref_dir(struct ref_dir
*dir
)
495 struct ref_entry
*last
= NULL
;
498 * This check also prevents passing a zero-length array to qsort(),
499 * which is a problem on some platforms.
501 if (dir
->sorted
== dir
->nr
)
504 qsort(dir
->entries
, dir
->nr
, sizeof(*dir
->entries
), ref_entry_cmp
);
506 /* Remove any duplicates: */
507 for (i
= 0, j
= 0; j
< dir
->nr
; j
++) {
508 struct ref_entry
*entry
= dir
->entries
[j
];
509 if (last
&& is_dup_ref(last
, entry
))
510 free_ref_entry(entry
);
512 last
= dir
->entries
[i
++] = entry
;
514 dir
->sorted
= dir
->nr
= i
;
518 * Return true if refname, which has the specified oid and flags, can
519 * be resolved to an object in the database. If the referred-to object
520 * does not exist, emit a warning and return false.
522 static int ref_resolves_to_object(const char *refname
,
523 const struct object_id
*oid
,
526 if (flags
& REF_ISBROKEN
)
528 if (!has_sha1_file(oid
->hash
)) {
529 error("%s does not point to a valid object!", refname
);
536 * Return true if the reference described by entry can be resolved to
537 * an object in the database; otherwise, emit a warning and return
540 static int entry_resolves_to_object(struct ref_entry
*entry
)
542 return ref_resolves_to_object(entry
->name
,
543 &entry
->u
.value
.oid
, entry
->flag
);
546 typedef int each_ref_entry_fn(struct ref_entry
*entry
, void *cb_data
);
549 * Call fn for each reference in dir that has index in the range
550 * offset <= index < dir->nr. Recurse into subdirectories that are in
551 * that index range, sorting them before iterating. This function
552 * does not sort dir itself; it should be sorted beforehand. fn is
553 * called for all references, including broken ones.
555 static int do_for_each_entry_in_dir(struct ref_dir
*dir
, int offset
,
556 each_ref_entry_fn fn
, void *cb_data
)
559 assert(dir
->sorted
== dir
->nr
);
560 for (i
= offset
; i
< dir
->nr
; i
++) {
561 struct ref_entry
*entry
= dir
->entries
[i
];
563 if (entry
->flag
& REF_DIR
) {
564 struct ref_dir
*subdir
= get_ref_dir(entry
);
565 sort_ref_dir(subdir
);
566 retval
= do_for_each_entry_in_dir(subdir
, 0, fn
, cb_data
);
568 retval
= fn(entry
, cb_data
);
577 * Load all of the refs from the dir into our in-memory cache. The hard work
578 * of loading loose refs is done by get_ref_dir(), so we just need to recurse
579 * through all of the sub-directories. We do not even need to care about
580 * sorting, as traversal order does not matter to us.
582 static void prime_ref_dir(struct ref_dir
*dir
)
585 for (i
= 0; i
< dir
->nr
; i
++) {
586 struct ref_entry
*entry
= dir
->entries
[i
];
587 if (entry
->flag
& REF_DIR
)
588 prime_ref_dir(get_ref_dir(entry
));
593 * A level in the reference hierarchy that is currently being iterated
596 struct cache_ref_iterator_level
{
598 * The ref_dir being iterated over at this level. The ref_dir
599 * is sorted before being stored here.
604 * The index of the current entry within dir (which might
605 * itself be a directory). If index == -1, then the iteration
606 * hasn't yet begun. If index == dir->nr, then the iteration
607 * through this level is over.
613 * Represent an iteration through a ref_dir in the memory cache. The
614 * iteration recurses through subdirectories.
616 struct cache_ref_iterator
{
617 struct ref_iterator base
;
620 * The number of levels currently on the stack. This is always
621 * at least 1, because when it becomes zero the iteration is
622 * ended and this struct is freed.
626 /* The number of levels that have been allocated on the stack */
630 * A stack of levels. levels[0] is the uppermost level that is
631 * being iterated over in this iteration. (This is not
632 * necessary the top level in the references hierarchy. If we
633 * are iterating through a subtree, then levels[0] will hold
634 * the ref_dir for that subtree, and subsequent levels will go
637 struct cache_ref_iterator_level
*levels
;
640 static int cache_ref_iterator_advance(struct ref_iterator
*ref_iterator
)
642 struct cache_ref_iterator
*iter
=
643 (struct cache_ref_iterator
*)ref_iterator
;
646 struct cache_ref_iterator_level
*level
=
647 &iter
->levels
[iter
->levels_nr
- 1];
648 struct ref_dir
*dir
= level
->dir
;
649 struct ref_entry
*entry
;
651 if (level
->index
== -1)
654 if (++level
->index
== level
->dir
->nr
) {
655 /* This level is exhausted; pop up a level */
656 if (--iter
->levels_nr
== 0)
657 return ref_iterator_abort(ref_iterator
);
662 entry
= dir
->entries
[level
->index
];
664 if (entry
->flag
& REF_DIR
) {
665 /* push down a level */
666 ALLOC_GROW(iter
->levels
, iter
->levels_nr
+ 1,
669 level
= &iter
->levels
[iter
->levels_nr
++];
670 level
->dir
= get_ref_dir(entry
);
673 iter
->base
.refname
= entry
->name
;
674 iter
->base
.oid
= &entry
->u
.value
.oid
;
675 iter
->base
.flags
= entry
->flag
;
681 static enum peel_status
peel_entry(struct ref_entry
*entry
, int repeel
);
683 static int cache_ref_iterator_peel(struct ref_iterator
*ref_iterator
,
684 struct object_id
*peeled
)
686 struct cache_ref_iterator
*iter
=
687 (struct cache_ref_iterator
*)ref_iterator
;
688 struct cache_ref_iterator_level
*level
;
689 struct ref_entry
*entry
;
691 level
= &iter
->levels
[iter
->levels_nr
- 1];
693 if (level
->index
== -1)
694 die("BUG: peel called before advance for cache iterator");
696 entry
= level
->dir
->entries
[level
->index
];
698 if (peel_entry(entry
, 0))
700 hashcpy(peeled
->hash
, entry
->u
.value
.peeled
.hash
);
704 static int cache_ref_iterator_abort(struct ref_iterator
*ref_iterator
)
706 struct cache_ref_iterator
*iter
=
707 (struct cache_ref_iterator
*)ref_iterator
;
710 base_ref_iterator_free(ref_iterator
);
714 static struct ref_iterator_vtable cache_ref_iterator_vtable
= {
715 cache_ref_iterator_advance
,
716 cache_ref_iterator_peel
,
717 cache_ref_iterator_abort
720 static struct ref_iterator
*cache_ref_iterator_begin(struct ref_dir
*dir
)
722 struct cache_ref_iterator
*iter
;
723 struct ref_iterator
*ref_iterator
;
724 struct cache_ref_iterator_level
*level
;
726 iter
= xcalloc(1, sizeof(*iter
));
727 ref_iterator
= &iter
->base
;
728 base_ref_iterator_init(ref_iterator
, &cache_ref_iterator_vtable
);
729 ALLOC_GROW(iter
->levels
, 10, iter
->levels_alloc
);
732 level
= &iter
->levels
[0];
739 struct nonmatching_ref_data
{
740 const struct string_list
*skip
;
741 const char *conflicting_refname
;
744 static int nonmatching_ref_fn(struct ref_entry
*entry
, void *vdata
)
746 struct nonmatching_ref_data
*data
= vdata
;
748 if (data
->skip
&& string_list_has_string(data
->skip
, entry
->name
))
751 data
->conflicting_refname
= entry
->name
;
756 * Return 0 if a reference named refname could be created without
757 * conflicting with the name of an existing reference in dir.
758 * See verify_refname_available for more information.
760 static int verify_refname_available_dir(const char *refname
,
761 const struct string_list
*extras
,
762 const struct string_list
*skip
,
767 const char *extra_refname
;
769 struct strbuf dirname
= STRBUF_INIT
;
773 * For the sake of comments in this function, suppose that
774 * refname is "refs/foo/bar".
779 strbuf_grow(&dirname
, strlen(refname
) + 1);
780 for (slash
= strchr(refname
, '/'); slash
; slash
= strchr(slash
+ 1, '/')) {
781 /* Expand dirname to the new prefix, not including the trailing slash: */
782 strbuf_add(&dirname
, refname
+ dirname
.len
, slash
- refname
- dirname
.len
);
785 * We are still at a leading dir of the refname (e.g.,
786 * "refs/foo"; if there is a reference with that name,
787 * it is a conflict, *unless* it is in skip.
790 pos
= search_ref_dir(dir
, dirname
.buf
, dirname
.len
);
792 (!skip
|| !string_list_has_string(skip
, dirname
.buf
))) {
794 * We found a reference whose name is
795 * a proper prefix of refname; e.g.,
796 * "refs/foo", and is not in skip.
798 strbuf_addf(err
, "'%s' exists; cannot create '%s'",
799 dirname
.buf
, refname
);
804 if (extras
&& string_list_has_string(extras
, dirname
.buf
) &&
805 (!skip
|| !string_list_has_string(skip
, dirname
.buf
))) {
806 strbuf_addf(err
, "cannot process '%s' and '%s' at the same time",
807 refname
, dirname
.buf
);
812 * Otherwise, we can try to continue our search with
813 * the next component. So try to look up the
814 * directory, e.g., "refs/foo/". If we come up empty,
815 * we know there is nothing under this whole prefix,
816 * but even in that case we still have to continue the
817 * search for conflicts with extras.
819 strbuf_addch(&dirname
, '/');
821 pos
= search_ref_dir(dir
, dirname
.buf
, dirname
.len
);
824 * There was no directory "refs/foo/",
825 * so there is nothing under this
826 * whole prefix. So there is no need
827 * to continue looking for conflicting
828 * references. But we need to continue
829 * looking for conflicting extras.
833 dir
= get_ref_dir(dir
->entries
[pos
]);
839 * We are at the leaf of our refname (e.g., "refs/foo/bar").
840 * There is no point in searching for a reference with that
841 * name, because a refname isn't considered to conflict with
842 * itself. But we still need to check for references whose
843 * names are in the "refs/foo/bar/" namespace, because they
846 strbuf_addstr(&dirname
, refname
+ dirname
.len
);
847 strbuf_addch(&dirname
, '/');
850 pos
= search_ref_dir(dir
, dirname
.buf
, dirname
.len
);
854 * We found a directory named "$refname/"
855 * (e.g., "refs/foo/bar/"). It is a problem
856 * iff it contains any ref that is not in
859 struct nonmatching_ref_data data
;
862 data
.conflicting_refname
= NULL
;
863 dir
= get_ref_dir(dir
->entries
[pos
]);
865 if (do_for_each_entry_in_dir(dir
, 0, nonmatching_ref_fn
, &data
)) {
866 strbuf_addf(err
, "'%s' exists; cannot create '%s'",
867 data
.conflicting_refname
, refname
);
873 extra_refname
= find_descendant_ref(dirname
.buf
, extras
, skip
);
875 strbuf_addf(err
, "cannot process '%s' and '%s' at the same time",
876 refname
, extra_refname
);
881 strbuf_release(&dirname
);
885 struct packed_ref_cache
{
886 struct ref_entry
*root
;
889 * Count of references to the data structure in this instance,
890 * including the pointer from files_ref_store::packed if any.
891 * The data will not be freed as long as the reference count
894 unsigned int referrers
;
897 * Iff the packed-refs file associated with this instance is
898 * currently locked for writing, this points at the associated
899 * lock (which is owned by somebody else). The referrer count
900 * is also incremented when the file is locked and decremented
901 * when it is unlocked.
903 struct lock_file
*lock
;
905 /* The metadata from when this packed-refs cache was read */
906 struct stat_validity validity
;
910 * Future: need to be in "struct repository"
911 * when doing a full libification.
913 struct files_ref_store
{
914 struct ref_store base
;
915 struct ref_entry
*loose
;
916 struct packed_ref_cache
*packed
;
919 /* Lock used for the main packed-refs file: */
920 static struct lock_file packlock
;
923 * Increment the reference count of *packed_refs.
925 static void acquire_packed_ref_cache(struct packed_ref_cache
*packed_refs
)
927 packed_refs
->referrers
++;
931 * Decrease the reference count of *packed_refs. If it goes to zero,
932 * free *packed_refs and return true; otherwise return false.
934 static int release_packed_ref_cache(struct packed_ref_cache
*packed_refs
)
936 if (!--packed_refs
->referrers
) {
937 free_ref_entry(packed_refs
->root
);
938 stat_validity_clear(&packed_refs
->validity
);
946 static void clear_packed_ref_cache(struct files_ref_store
*refs
)
949 struct packed_ref_cache
*packed_refs
= refs
->packed
;
951 if (packed_refs
->lock
)
952 die("internal error: packed-ref cache cleared while locked");
954 release_packed_ref_cache(packed_refs
);
958 static void clear_loose_ref_cache(struct files_ref_store
*refs
)
961 free_ref_entry(refs
->loose
);
967 * Create a new submodule ref cache and add it to the internal
970 static struct ref_store
*files_ref_store_create(const char *submodule
)
972 struct files_ref_store
*refs
= xcalloc(1, sizeof(*refs
));
973 struct ref_store
*ref_store
= (struct ref_store
*)refs
;
975 base_ref_store_init(ref_store
, &refs_be_files
, submodule
);
981 * Downcast ref_store to files_ref_store. Die if ref_store is not a
982 * files_ref_store. If submodule_allowed is not true, then also die if
983 * files_ref_store is for a submodule (i.e., not for the main
984 * repository). caller is used in any necessary error messages.
986 static struct files_ref_store
*files_downcast(
987 struct ref_store
*ref_store
, int submodule_allowed
,
990 if (ref_store
->be
!= &refs_be_files
)
991 die("BUG: ref_store is type \"%s\" not \"files\" in %s",
992 ref_store
->be
->name
, caller
);
994 if (!submodule_allowed
)
995 assert_main_repository(ref_store
, caller
);
997 return (struct files_ref_store
*)ref_store
;
1001 * Return a pointer to the reference store for the specified
1002 * submodule. For the main repository, use submodule==NULL; such a
1003 * call cannot fail. For a submodule, the submodule must exist and be
1004 * a nonbare repository, otherwise return NULL. Verify that the
1005 * reference store is a files_ref_store, and cast it to that type
1006 * before returning it.
1008 static struct files_ref_store
*get_files_ref_store(const char *submodule
,
1011 struct ref_store
*refs
= get_ref_store(submodule
);
1013 return refs
? files_downcast(refs
, 1, caller
) : NULL
;
1016 /* The length of a peeled reference line in packed-refs, including EOL: */
1017 #define PEELED_LINE_LENGTH 42
1020 * The packed-refs header line that we write out. Perhaps other
1021 * traits will be added later. The trailing space is required.
1023 static const char PACKED_REFS_HEADER
[] =
1024 "# pack-refs with: peeled fully-peeled \n";
1027 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
1028 * Return a pointer to the refname within the line (null-terminated),
1029 * or NULL if there was a problem.
1031 static const char *parse_ref_line(struct strbuf
*line
, unsigned char *sha1
)
1036 * 42: the answer to everything.
1038 * In this case, it happens to be the answer to
1039 * 40 (length of sha1 hex representation)
1040 * +1 (space in between hex and name)
1041 * +1 (newline at the end of the line)
1043 if (line
->len
<= 42)
1046 if (get_sha1_hex(line
->buf
, sha1
) < 0)
1048 if (!isspace(line
->buf
[40]))
1051 ref
= line
->buf
+ 41;
1055 if (line
->buf
[line
->len
- 1] != '\n')
1057 line
->buf
[--line
->len
] = 0;
1063 * Read f, which is a packed-refs file, into dir.
1065 * A comment line of the form "# pack-refs with: " may contain zero or
1066 * more traits. We interpret the traits as follows:
1070 * Probably no references are peeled. But if the file contains a
1071 * peeled value for a reference, we will use it.
1075 * References under "refs/tags/", if they *can* be peeled, *are*
1076 * peeled in this file. References outside of "refs/tags/" are
1077 * probably not peeled even if they could have been, but if we find
1078 * a peeled value for such a reference we will use it.
1082 * All references in the file that can be peeled are peeled.
1083 * Inversely (and this is more important), any references in the
1084 * file for which no peeled value is recorded is not peelable. This
1085 * trait should typically be written alongside "peeled" for
1086 * compatibility with older clients, but we do not require it
1087 * (i.e., "peeled" is a no-op if "fully-peeled" is set).
1089 static void read_packed_refs(FILE *f
, struct ref_dir
*dir
)
1091 struct ref_entry
*last
= NULL
;
1092 struct strbuf line
= STRBUF_INIT
;
1093 enum { PEELED_NONE
, PEELED_TAGS
, PEELED_FULLY
} peeled
= PEELED_NONE
;
1095 while (strbuf_getwholeline(&line
, f
, '\n') != EOF
) {
1096 unsigned char sha1
[20];
1097 const char *refname
;
1100 if (skip_prefix(line
.buf
, "# pack-refs with:", &traits
)) {
1101 if (strstr(traits
, " fully-peeled "))
1102 peeled
= PEELED_FULLY
;
1103 else if (strstr(traits
, " peeled "))
1104 peeled
= PEELED_TAGS
;
1105 /* perhaps other traits later as well */
1109 refname
= parse_ref_line(&line
, sha1
);
1111 int flag
= REF_ISPACKED
;
1113 if (check_refname_format(refname
, REFNAME_ALLOW_ONELEVEL
)) {
1114 if (!refname_is_safe(refname
))
1115 die("packed refname is dangerous: %s", refname
);
1117 flag
|= REF_BAD_NAME
| REF_ISBROKEN
;
1119 last
= create_ref_entry(refname
, sha1
, flag
, 0);
1120 if (peeled
== PEELED_FULLY
||
1121 (peeled
== PEELED_TAGS
&& starts_with(refname
, "refs/tags/")))
1122 last
->flag
|= REF_KNOWS_PEELED
;
1127 line
.buf
[0] == '^' &&
1128 line
.len
== PEELED_LINE_LENGTH
&&
1129 line
.buf
[PEELED_LINE_LENGTH
- 1] == '\n' &&
1130 !get_sha1_hex(line
.buf
+ 1, sha1
)) {
1131 hashcpy(last
->u
.value
.peeled
.hash
, sha1
);
1133 * Regardless of what the file header said,
1134 * we definitely know the value of *this*
1137 last
->flag
|= REF_KNOWS_PEELED
;
1141 strbuf_release(&line
);
1145 * Get the packed_ref_cache for the specified files_ref_store,
1146 * creating it if necessary.
1148 static struct packed_ref_cache
*get_packed_ref_cache(struct files_ref_store
*refs
)
1150 char *packed_refs_file
;
1152 if (*refs
->base
.submodule
)
1153 packed_refs_file
= git_pathdup_submodule(refs
->base
.submodule
,
1156 packed_refs_file
= git_pathdup("packed-refs");
1159 !stat_validity_check(&refs
->packed
->validity
, packed_refs_file
))
1160 clear_packed_ref_cache(refs
);
1162 if (!refs
->packed
) {
1165 refs
->packed
= xcalloc(1, sizeof(*refs
->packed
));
1166 acquire_packed_ref_cache(refs
->packed
);
1167 refs
->packed
->root
= create_dir_entry(refs
, "", 0, 0);
1168 f
= fopen(packed_refs_file
, "r");
1170 stat_validity_update(&refs
->packed
->validity
, fileno(f
));
1171 read_packed_refs(f
, get_ref_dir(refs
->packed
->root
));
1175 free(packed_refs_file
);
1176 return refs
->packed
;
1179 static struct ref_dir
*get_packed_ref_dir(struct packed_ref_cache
*packed_ref_cache
)
1181 return get_ref_dir(packed_ref_cache
->root
);
1184 static struct ref_dir
*get_packed_refs(struct files_ref_store
*refs
)
1186 return get_packed_ref_dir(get_packed_ref_cache(refs
));
1190 * Add a reference to the in-memory packed reference cache. This may
1191 * only be called while the packed-refs file is locked (see
1192 * lock_packed_refs()). To actually write the packed-refs file, call
1193 * commit_packed_refs().
1195 static void add_packed_ref(struct files_ref_store
*refs
,
1196 const char *refname
, const unsigned char *sha1
)
1198 struct packed_ref_cache
*packed_ref_cache
= get_packed_ref_cache(refs
);
1200 if (!packed_ref_cache
->lock
)
1201 die("internal error: packed refs not locked");
1202 add_ref(get_packed_ref_dir(packed_ref_cache
),
1203 create_ref_entry(refname
, sha1
, REF_ISPACKED
, 1));
1207 * Read the loose references from the namespace dirname into dir
1208 * (without recursing). dirname must end with '/'. dir must be the
1209 * directory entry corresponding to dirname.
1211 static void read_loose_refs(const char *dirname
, struct ref_dir
*dir
)
1213 struct files_ref_store
*refs
= dir
->ref_store
;
1216 int dirnamelen
= strlen(dirname
);
1217 struct strbuf refname
;
1218 struct strbuf path
= STRBUF_INIT
;
1219 size_t path_baselen
;
1221 if (*refs
->base
.submodule
)
1222 strbuf_git_path_submodule(&path
, refs
->base
.submodule
, "%s", dirname
);
1224 strbuf_git_path(&path
, "%s", dirname
);
1225 path_baselen
= path
.len
;
1227 d
= opendir(path
.buf
);
1229 strbuf_release(&path
);
1233 strbuf_init(&refname
, dirnamelen
+ 257);
1234 strbuf_add(&refname
, dirname
, dirnamelen
);
1236 while ((de
= readdir(d
)) != NULL
) {
1237 unsigned char sha1
[20];
1241 if (de
->d_name
[0] == '.')
1243 if (ends_with(de
->d_name
, ".lock"))
1245 strbuf_addstr(&refname
, de
->d_name
);
1246 strbuf_addstr(&path
, de
->d_name
);
1247 if (stat(path
.buf
, &st
) < 0) {
1248 ; /* silently ignore */
1249 } else if (S_ISDIR(st
.st_mode
)) {
1250 strbuf_addch(&refname
, '/');
1251 add_entry_to_dir(dir
,
1252 create_dir_entry(refs
, refname
.buf
,
1257 if (*refs
->base
.submodule
) {
1260 read_ok
= !resolve_gitlink_ref(refs
->base
.submodule
,
1263 read_ok
= !read_ref_full(refname
.buf
,
1264 RESOLVE_REF_READING
,
1270 flag
|= REF_ISBROKEN
;
1271 } else if (is_null_sha1(sha1
)) {
1273 * It is so astronomically unlikely
1274 * that NULL_SHA1 is the SHA-1 of an
1275 * actual object that we consider its
1276 * appearance in a loose reference
1277 * file to be repo corruption
1278 * (probably due to a software bug).
1280 flag
|= REF_ISBROKEN
;
1283 if (check_refname_format(refname
.buf
,
1284 REFNAME_ALLOW_ONELEVEL
)) {
1285 if (!refname_is_safe(refname
.buf
))
1286 die("loose refname is dangerous: %s", refname
.buf
);
1288 flag
|= REF_BAD_NAME
| REF_ISBROKEN
;
1290 add_entry_to_dir(dir
,
1291 create_ref_entry(refname
.buf
, sha1
, flag
, 0));
1293 strbuf_setlen(&refname
, dirnamelen
);
1294 strbuf_setlen(&path
, path_baselen
);
1296 strbuf_release(&refname
);
1297 strbuf_release(&path
);
1301 static struct ref_dir
*get_loose_refs(struct files_ref_store
*refs
)
1305 * Mark the top-level directory complete because we
1306 * are about to read the only subdirectory that can
1309 refs
->loose
= create_dir_entry(refs
, "", 0, 0);
1311 * Create an incomplete entry for "refs/":
1313 add_entry_to_dir(get_ref_dir(refs
->loose
),
1314 create_dir_entry(refs
, "refs/", 5, 1));
1316 return get_ref_dir(refs
->loose
);
1320 * Return the ref_entry for the given refname from the packed
1321 * references. If it does not exist, return NULL.
1323 static struct ref_entry
*get_packed_ref(struct files_ref_store
*refs
,
1324 const char *refname
)
1326 return find_ref(get_packed_refs(refs
), refname
);
1330 * A loose ref file doesn't exist; check for a packed ref.
1332 static int resolve_packed_ref(struct files_ref_store
*refs
,
1333 const char *refname
,
1334 unsigned char *sha1
, unsigned int *flags
)
1336 struct ref_entry
*entry
;
1339 * The loose reference file does not exist; check for a packed
1342 entry
= get_packed_ref(refs
, refname
);
1344 hashcpy(sha1
, entry
->u
.value
.oid
.hash
);
1345 *flags
|= REF_ISPACKED
;
1348 /* refname is not a packed reference. */
1352 static int files_read_raw_ref(struct ref_store
*ref_store
,
1353 const char *refname
, unsigned char *sha1
,
1354 struct strbuf
*referent
, unsigned int *type
)
1356 struct files_ref_store
*refs
=
1357 files_downcast(ref_store
, 1, "read_raw_ref");
1358 struct strbuf sb_contents
= STRBUF_INIT
;
1359 struct strbuf sb_path
= STRBUF_INIT
;
1368 strbuf_reset(&sb_path
);
1370 if (*refs
->base
.submodule
)
1371 strbuf_git_path_submodule(&sb_path
, refs
->base
.submodule
, "%s", refname
);
1373 strbuf_git_path(&sb_path
, "%s", refname
);
1379 * We might have to loop back here to avoid a race
1380 * condition: first we lstat() the file, then we try
1381 * to read it as a link or as a file. But if somebody
1382 * changes the type of the file (file <-> directory
1383 * <-> symlink) between the lstat() and reading, then
1384 * we don't want to report that as an error but rather
1385 * try again starting with the lstat().
1388 if (lstat(path
, &st
) < 0) {
1389 if (errno
!= ENOENT
)
1391 if (resolve_packed_ref(refs
, refname
, sha1
, type
)) {
1399 /* Follow "normalized" - ie "refs/.." symlinks by hand */
1400 if (S_ISLNK(st
.st_mode
)) {
1401 strbuf_reset(&sb_contents
);
1402 if (strbuf_readlink(&sb_contents
, path
, 0) < 0) {
1403 if (errno
== ENOENT
|| errno
== EINVAL
)
1404 /* inconsistent with lstat; retry */
1409 if (starts_with(sb_contents
.buf
, "refs/") &&
1410 !check_refname_format(sb_contents
.buf
, 0)) {
1411 strbuf_swap(&sb_contents
, referent
);
1412 *type
|= REF_ISSYMREF
;
1418 /* Is it a directory? */
1419 if (S_ISDIR(st
.st_mode
)) {
1421 * Even though there is a directory where the loose
1422 * ref is supposed to be, there could still be a
1425 if (resolve_packed_ref(refs
, refname
, sha1
, type
)) {
1434 * Anything else, just open it and try to use it as
1437 fd
= open(path
, O_RDONLY
);
1439 if (errno
== ENOENT
)
1440 /* inconsistent with lstat; retry */
1445 strbuf_reset(&sb_contents
);
1446 if (strbuf_read(&sb_contents
, fd
, 256) < 0) {
1447 int save_errno
= errno
;
1453 strbuf_rtrim(&sb_contents
);
1454 buf
= sb_contents
.buf
;
1455 if (starts_with(buf
, "ref:")) {
1457 while (isspace(*buf
))
1460 strbuf_reset(referent
);
1461 strbuf_addstr(referent
, buf
);
1462 *type
|= REF_ISSYMREF
;
1468 * Please note that FETCH_HEAD has additional
1469 * data after the sha.
1471 if (get_sha1_hex(buf
, sha1
) ||
1472 (buf
[40] != '\0' && !isspace(buf
[40]))) {
1473 *type
|= REF_ISBROKEN
;
1482 strbuf_release(&sb_path
);
1483 strbuf_release(&sb_contents
);
1488 static void unlock_ref(struct ref_lock
*lock
)
1490 /* Do not free lock->lk -- atexit() still looks at them */
1492 rollback_lock_file(lock
->lk
);
1493 free(lock
->ref_name
);
1498 * Lock refname, without following symrefs, and set *lock_p to point
1499 * at a newly-allocated lock object. Fill in lock->old_oid, referent,
1500 * and type similarly to read_raw_ref().
1502 * The caller must verify that refname is a "safe" reference name (in
1503 * the sense of refname_is_safe()) before calling this function.
1505 * If the reference doesn't already exist, verify that refname doesn't
1506 * have a D/F conflict with any existing references. extras and skip
1507 * are passed to verify_refname_available_dir() for this check.
1509 * If mustexist is not set and the reference is not found or is
1510 * broken, lock the reference anyway but clear sha1.
1512 * Return 0 on success. On failure, write an error message to err and
1513 * return TRANSACTION_NAME_CONFLICT or TRANSACTION_GENERIC_ERROR.
1515 * Implementation note: This function is basically
1520 * but it includes a lot more code to
1521 * - Deal with possible races with other processes
1522 * - Avoid calling verify_refname_available_dir() when it can be
1523 * avoided, namely if we were successfully able to read the ref
1524 * - Generate informative error messages in the case of failure
1526 static int lock_raw_ref(const char *refname
, int mustexist
,
1527 const struct string_list
*extras
,
1528 const struct string_list
*skip
,
1529 struct ref_lock
**lock_p
,
1530 struct strbuf
*referent
,
1534 struct ref_store
*ref_store
= get_ref_store(NULL
);
1535 struct files_ref_store
*refs
=
1536 files_downcast(ref_store
, 0, "lock_raw_ref");
1537 struct ref_lock
*lock
;
1538 struct strbuf ref_file
= STRBUF_INIT
;
1539 int attempts_remaining
= 3;
1540 int ret
= TRANSACTION_GENERIC_ERROR
;
1545 /* First lock the file so it can't change out from under us. */
1547 *lock_p
= lock
= xcalloc(1, sizeof(*lock
));
1549 lock
->ref_name
= xstrdup(refname
);
1550 strbuf_git_path(&ref_file
, "%s", refname
);
1553 switch (safe_create_leading_directories(ref_file
.buf
)) {
1555 break; /* success */
1558 * Suppose refname is "refs/foo/bar". We just failed
1559 * to create the containing directory, "refs/foo",
1560 * because there was a non-directory in the way. This
1561 * indicates a D/F conflict, probably because of
1562 * another reference such as "refs/foo". There is no
1563 * reason to expect this error to be transitory.
1565 if (verify_refname_available(refname
, extras
, skip
, err
)) {
1568 * To the user the relevant error is
1569 * that the "mustexist" reference is
1573 strbuf_addf(err
, "unable to resolve reference '%s'",
1577 * The error message set by
1578 * verify_refname_available_dir() is OK.
1580 ret
= TRANSACTION_NAME_CONFLICT
;
1584 * The file that is in the way isn't a loose
1585 * reference. Report it as a low-level
1588 strbuf_addf(err
, "unable to create lock file %s.lock; "
1589 "non-directory in the way",
1594 /* Maybe another process was tidying up. Try again. */
1595 if (--attempts_remaining
> 0)
1599 strbuf_addf(err
, "unable to create directory for %s",
1605 lock
->lk
= xcalloc(1, sizeof(struct lock_file
));
1607 if (hold_lock_file_for_update(lock
->lk
, ref_file
.buf
, LOCK_NO_DEREF
) < 0) {
1608 if (errno
== ENOENT
&& --attempts_remaining
> 0) {
1610 * Maybe somebody just deleted one of the
1611 * directories leading to ref_file. Try
1616 unable_to_lock_message(ref_file
.buf
, errno
, err
);
1622 * Now we hold the lock and can read the reference without
1623 * fear that its value will change.
1626 if (files_read_raw_ref(ref_store
, refname
,
1627 lock
->old_oid
.hash
, referent
, type
)) {
1628 if (errno
== ENOENT
) {
1630 /* Garden variety missing reference. */
1631 strbuf_addf(err
, "unable to resolve reference '%s'",
1636 * Reference is missing, but that's OK. We
1637 * know that there is not a conflict with
1638 * another loose reference because
1639 * (supposing that we are trying to lock
1640 * reference "refs/foo/bar"):
1642 * - We were successfully able to create
1643 * the lockfile refs/foo/bar.lock, so we
1644 * know there cannot be a loose reference
1647 * - We got ENOENT and not EISDIR, so we
1648 * know that there cannot be a loose
1649 * reference named "refs/foo/bar/baz".
1652 } else if (errno
== EISDIR
) {
1654 * There is a directory in the way. It might have
1655 * contained references that have been deleted. If
1656 * we don't require that the reference already
1657 * exists, try to remove the directory so that it
1658 * doesn't cause trouble when we want to rename the
1659 * lockfile into place later.
1662 /* Garden variety missing reference. */
1663 strbuf_addf(err
, "unable to resolve reference '%s'",
1666 } else if (remove_dir_recursively(&ref_file
,
1667 REMOVE_DIR_EMPTY_ONLY
)) {
1668 if (verify_refname_available_dir(
1669 refname
, extras
, skip
,
1670 get_loose_refs(refs
),
1673 * The error message set by
1674 * verify_refname_available() is OK.
1676 ret
= TRANSACTION_NAME_CONFLICT
;
1680 * We can't delete the directory,
1681 * but we also don't know of any
1682 * references that it should
1685 strbuf_addf(err
, "there is a non-empty directory '%s' "
1686 "blocking reference '%s'",
1687 ref_file
.buf
, refname
);
1691 } else if (errno
== EINVAL
&& (*type
& REF_ISBROKEN
)) {
1692 strbuf_addf(err
, "unable to resolve reference '%s': "
1693 "reference broken", refname
);
1696 strbuf_addf(err
, "unable to resolve reference '%s': %s",
1697 refname
, strerror(errno
));
1702 * If the ref did not exist and we are creating it,
1703 * make sure there is no existing packed ref whose
1704 * name begins with our refname, nor a packed ref
1705 * whose name is a proper prefix of our refname.
1707 if (verify_refname_available_dir(
1708 refname
, extras
, skip
,
1709 get_packed_refs(refs
),
1723 strbuf_release(&ref_file
);
1728 * Peel the entry (if possible) and return its new peel_status. If
1729 * repeel is true, re-peel the entry even if there is an old peeled
1730 * value that is already stored in it.
1732 * It is OK to call this function with a packed reference entry that
1733 * might be stale and might even refer to an object that has since
1734 * been garbage-collected. In such a case, if the entry has
1735 * REF_KNOWS_PEELED then leave the status unchanged and return
1736 * PEEL_PEELED or PEEL_NON_TAG; otherwise, return PEEL_INVALID.
1738 static enum peel_status
peel_entry(struct ref_entry
*entry
, int repeel
)
1740 enum peel_status status
;
1742 if (entry
->flag
& REF_KNOWS_PEELED
) {
1744 entry
->flag
&= ~REF_KNOWS_PEELED
;
1745 oidclr(&entry
->u
.value
.peeled
);
1747 return is_null_oid(&entry
->u
.value
.peeled
) ?
1748 PEEL_NON_TAG
: PEEL_PEELED
;
1751 if (entry
->flag
& REF_ISBROKEN
)
1753 if (entry
->flag
& REF_ISSYMREF
)
1754 return PEEL_IS_SYMREF
;
1756 status
= peel_object(entry
->u
.value
.oid
.hash
, entry
->u
.value
.peeled
.hash
);
1757 if (status
== PEEL_PEELED
|| status
== PEEL_NON_TAG
)
1758 entry
->flag
|= REF_KNOWS_PEELED
;
1762 int peel_ref(const char *refname
, unsigned char *sha1
)
1764 struct files_ref_store
*refs
= get_files_ref_store(NULL
, "peel_ref");
1766 unsigned char base
[20];
1768 if (current_ref_iter
&& current_ref_iter
->refname
== refname
) {
1769 struct object_id peeled
;
1771 if (ref_iterator_peel(current_ref_iter
, &peeled
))
1773 hashcpy(sha1
, peeled
.hash
);
1777 if (read_ref_full(refname
, RESOLVE_REF_READING
, base
, &flag
))
1781 * If the reference is packed, read its ref_entry from the
1782 * cache in the hope that we already know its peeled value.
1783 * We only try this optimization on packed references because
1784 * (a) forcing the filling of the loose reference cache could
1785 * be expensive and (b) loose references anyway usually do not
1786 * have REF_KNOWS_PEELED.
1788 if (flag
& REF_ISPACKED
) {
1789 struct ref_entry
*r
= get_packed_ref(refs
, refname
);
1791 if (peel_entry(r
, 0))
1793 hashcpy(sha1
, r
->u
.value
.peeled
.hash
);
1798 return peel_object(base
, sha1
);
1801 struct files_ref_iterator
{
1802 struct ref_iterator base
;
1804 struct packed_ref_cache
*packed_ref_cache
;
1805 struct ref_iterator
*iter0
;
1809 static int files_ref_iterator_advance(struct ref_iterator
*ref_iterator
)
1811 struct files_ref_iterator
*iter
=
1812 (struct files_ref_iterator
*)ref_iterator
;
1815 while ((ok
= ref_iterator_advance(iter
->iter0
)) == ITER_OK
) {
1816 if (!(iter
->flags
& DO_FOR_EACH_INCLUDE_BROKEN
) &&
1817 !ref_resolves_to_object(iter
->iter0
->refname
,
1819 iter
->iter0
->flags
))
1822 iter
->base
.refname
= iter
->iter0
->refname
;
1823 iter
->base
.oid
= iter
->iter0
->oid
;
1824 iter
->base
.flags
= iter
->iter0
->flags
;
1829 if (ref_iterator_abort(ref_iterator
) != ITER_DONE
)
1835 static int files_ref_iterator_peel(struct ref_iterator
*ref_iterator
,
1836 struct object_id
*peeled
)
1838 struct files_ref_iterator
*iter
=
1839 (struct files_ref_iterator
*)ref_iterator
;
1841 return ref_iterator_peel(iter
->iter0
, peeled
);
1844 static int files_ref_iterator_abort(struct ref_iterator
*ref_iterator
)
1846 struct files_ref_iterator
*iter
=
1847 (struct files_ref_iterator
*)ref_iterator
;
1851 ok
= ref_iterator_abort(iter
->iter0
);
1853 release_packed_ref_cache(iter
->packed_ref_cache
);
1854 base_ref_iterator_free(ref_iterator
);
1858 static struct ref_iterator_vtable files_ref_iterator_vtable
= {
1859 files_ref_iterator_advance
,
1860 files_ref_iterator_peel
,
1861 files_ref_iterator_abort
1864 struct ref_iterator
*files_ref_iterator_begin(
1865 const char *submodule
,
1866 const char *prefix
, unsigned int flags
)
1868 struct files_ref_store
*refs
=
1869 get_files_ref_store(submodule
, "ref_iterator_begin");
1870 struct ref_dir
*loose_dir
, *packed_dir
;
1871 struct ref_iterator
*loose_iter
, *packed_iter
;
1872 struct files_ref_iterator
*iter
;
1873 struct ref_iterator
*ref_iterator
;
1876 return empty_ref_iterator_begin();
1878 if (ref_paranoia
< 0)
1879 ref_paranoia
= git_env_bool("GIT_REF_PARANOIA", 0);
1881 flags
|= DO_FOR_EACH_INCLUDE_BROKEN
;
1883 iter
= xcalloc(1, sizeof(*iter
));
1884 ref_iterator
= &iter
->base
;
1885 base_ref_iterator_init(ref_iterator
, &files_ref_iterator_vtable
);
1888 * We must make sure that all loose refs are read before
1889 * accessing the packed-refs file; this avoids a race
1890 * condition if loose refs are migrated to the packed-refs
1891 * file by a simultaneous process, but our in-memory view is
1892 * from before the migration. We ensure this as follows:
1893 * First, we call prime_ref_dir(), which pre-reads the loose
1894 * references for the subtree into the cache. (If they've
1895 * already been read, that's OK; we only need to guarantee
1896 * that they're read before the packed refs, not *how much*
1897 * before.) After that, we call get_packed_ref_cache(), which
1898 * internally checks whether the packed-ref cache is up to
1899 * date with what is on disk, and re-reads it if not.
1902 loose_dir
= get_loose_refs(refs
);
1904 if (prefix
&& *prefix
)
1905 loose_dir
= find_containing_dir(loose_dir
, prefix
, 0);
1908 prime_ref_dir(loose_dir
);
1909 loose_iter
= cache_ref_iterator_begin(loose_dir
);
1911 /* There's nothing to iterate over. */
1912 loose_iter
= empty_ref_iterator_begin();
1915 iter
->packed_ref_cache
= get_packed_ref_cache(refs
);
1916 acquire_packed_ref_cache(iter
->packed_ref_cache
);
1917 packed_dir
= get_packed_ref_dir(iter
->packed_ref_cache
);
1919 if (prefix
&& *prefix
)
1920 packed_dir
= find_containing_dir(packed_dir
, prefix
, 0);
1923 packed_iter
= cache_ref_iterator_begin(packed_dir
);
1925 /* There's nothing to iterate over. */
1926 packed_iter
= empty_ref_iterator_begin();
1929 iter
->iter0
= overlay_ref_iterator_begin(loose_iter
, packed_iter
);
1930 iter
->flags
= flags
;
1932 return ref_iterator
;
1936 * Verify that the reference locked by lock has the value old_sha1.
1937 * Fail if the reference doesn't exist and mustexist is set. Return 0
1938 * on success. On error, write an error message to err, set errno, and
1939 * return a negative value.
1941 static int verify_lock(struct ref_lock
*lock
,
1942 const unsigned char *old_sha1
, int mustexist
,
1947 if (read_ref_full(lock
->ref_name
,
1948 mustexist
? RESOLVE_REF_READING
: 0,
1949 lock
->old_oid
.hash
, NULL
)) {
1951 int save_errno
= errno
;
1952 strbuf_addf(err
, "can't verify ref '%s'", lock
->ref_name
);
1956 hashclr(lock
->old_oid
.hash
);
1960 if (old_sha1
&& hashcmp(lock
->old_oid
.hash
, old_sha1
)) {
1961 strbuf_addf(err
, "ref '%s' is at %s but expected %s",
1963 sha1_to_hex(lock
->old_oid
.hash
),
1964 sha1_to_hex(old_sha1
));
1971 static int remove_empty_directories(struct strbuf
*path
)
1974 * we want to create a file but there is a directory there;
1975 * if that is an empty directory (or a directory that contains
1976 * only empty directories), remove them.
1978 return remove_dir_recursively(path
, REMOVE_DIR_EMPTY_ONLY
);
1982 * Locks a ref returning the lock on success and NULL on failure.
1983 * On failure errno is set to something meaningful.
1985 static struct ref_lock
*lock_ref_sha1_basic(const char *refname
,
1986 const unsigned char *old_sha1
,
1987 const struct string_list
*extras
,
1988 const struct string_list
*skip
,
1989 unsigned int flags
, int *type
,
1992 struct files_ref_store
*refs
=
1993 get_files_ref_store(NULL
, "lock_ref_sha1_basic");
1994 struct strbuf ref_file
= STRBUF_INIT
;
1995 struct ref_lock
*lock
;
1997 int lflags
= LOCK_NO_DEREF
;
1998 int mustexist
= (old_sha1
&& !is_null_sha1(old_sha1
));
1999 int resolve_flags
= RESOLVE_REF_NO_RECURSE
;
2000 int attempts_remaining
= 3;
2005 lock
= xcalloc(1, sizeof(struct ref_lock
));
2008 resolve_flags
|= RESOLVE_REF_READING
;
2009 if (flags
& REF_DELETING
)
2010 resolve_flags
|= RESOLVE_REF_ALLOW_BAD_NAME
;
2012 strbuf_git_path(&ref_file
, "%s", refname
);
2013 resolved
= !!resolve_ref_unsafe(refname
, resolve_flags
,
2014 lock
->old_oid
.hash
, type
);
2015 if (!resolved
&& errno
== EISDIR
) {
2017 * we are trying to lock foo but we used to
2018 * have foo/bar which now does not exist;
2019 * it is normal for the empty directory 'foo'
2022 if (remove_empty_directories(&ref_file
)) {
2024 if (!verify_refname_available_dir(
2025 refname
, extras
, skip
,
2026 get_loose_refs(refs
), err
))
2027 strbuf_addf(err
, "there are still refs under '%s'",
2031 resolved
= !!resolve_ref_unsafe(refname
, resolve_flags
,
2032 lock
->old_oid
.hash
, type
);
2036 if (last_errno
!= ENOTDIR
||
2037 !verify_refname_available_dir(
2038 refname
, extras
, skip
,
2039 get_loose_refs(refs
), err
))
2040 strbuf_addf(err
, "unable to resolve reference '%s': %s",
2041 refname
, strerror(last_errno
));
2047 * If the ref did not exist and we are creating it, make sure
2048 * there is no existing packed ref whose name begins with our
2049 * refname, nor a packed ref whose name is a proper prefix of
2052 if (is_null_oid(&lock
->old_oid
) &&
2053 verify_refname_available_dir(refname
, extras
, skip
,
2054 get_packed_refs(refs
),
2056 last_errno
= ENOTDIR
;
2060 lock
->lk
= xcalloc(1, sizeof(struct lock_file
));
2062 lock
->ref_name
= xstrdup(refname
);
2065 switch (safe_create_leading_directories_const(ref_file
.buf
)) {
2067 break; /* success */
2069 if (--attempts_remaining
> 0)
2074 strbuf_addf(err
, "unable to create directory for '%s'",
2079 if (hold_lock_file_for_update(lock
->lk
, ref_file
.buf
, lflags
) < 0) {
2081 if (errno
== ENOENT
&& --attempts_remaining
> 0)
2083 * Maybe somebody just deleted one of the
2084 * directories leading to ref_file. Try
2089 unable_to_lock_message(ref_file
.buf
, errno
, err
);
2093 if (verify_lock(lock
, old_sha1
, mustexist
, err
)) {
2104 strbuf_release(&ref_file
);
2110 * Write an entry to the packed-refs file for the specified refname.
2111 * If peeled is non-NULL, write it as the entry's peeled value.
2113 static void write_packed_entry(FILE *fh
, char *refname
, unsigned char *sha1
,
2114 unsigned char *peeled
)
2116 fprintf_or_die(fh
, "%s %s\n", sha1_to_hex(sha1
), refname
);
2118 fprintf_or_die(fh
, "^%s\n", sha1_to_hex(peeled
));
2122 * An each_ref_entry_fn that writes the entry to a packed-refs file.
2124 static int write_packed_entry_fn(struct ref_entry
*entry
, void *cb_data
)
2126 enum peel_status peel_status
= peel_entry(entry
, 0);
2128 if (peel_status
!= PEEL_PEELED
&& peel_status
!= PEEL_NON_TAG
)
2129 error("internal error: %s is not a valid packed reference!",
2131 write_packed_entry(cb_data
, entry
->name
, entry
->u
.value
.oid
.hash
,
2132 peel_status
== PEEL_PEELED
?
2133 entry
->u
.value
.peeled
.hash
: NULL
);
2138 * Lock the packed-refs file for writing. Flags is passed to
2139 * hold_lock_file_for_update(). Return 0 on success. On errors, set
2140 * errno appropriately and return a nonzero value.
2142 static int lock_packed_refs(struct files_ref_store
*refs
, int flags
)
2144 static int timeout_configured
= 0;
2145 static int timeout_value
= 1000;
2146 struct packed_ref_cache
*packed_ref_cache
;
2148 assert_main_repository(&refs
->base
, "lock_packed_refs");
2150 if (!timeout_configured
) {
2151 git_config_get_int("core.packedrefstimeout", &timeout_value
);
2152 timeout_configured
= 1;
2155 if (hold_lock_file_for_update_timeout(
2156 &packlock
, git_path("packed-refs"),
2157 flags
, timeout_value
) < 0)
2160 * Get the current packed-refs while holding the lock. If the
2161 * packed-refs file has been modified since we last read it,
2162 * this will automatically invalidate the cache and re-read
2163 * the packed-refs file.
2165 packed_ref_cache
= get_packed_ref_cache(refs
);
2166 packed_ref_cache
->lock
= &packlock
;
2167 /* Increment the reference count to prevent it from being freed: */
2168 acquire_packed_ref_cache(packed_ref_cache
);
2173 * Write the current version of the packed refs cache from memory to
2174 * disk. The packed-refs file must already be locked for writing (see
2175 * lock_packed_refs()). Return zero on success. On errors, set errno
2176 * and return a nonzero value
2178 static int commit_packed_refs(struct files_ref_store
*refs
)
2180 struct packed_ref_cache
*packed_ref_cache
=
2181 get_packed_ref_cache(refs
);
2186 assert_main_repository(&refs
->base
, "commit_packed_refs");
2188 if (!packed_ref_cache
->lock
)
2189 die("internal error: packed-refs not locked");
2191 out
= fdopen_lock_file(packed_ref_cache
->lock
, "w");
2193 die_errno("unable to fdopen packed-refs descriptor");
2195 fprintf_or_die(out
, "%s", PACKED_REFS_HEADER
);
2196 do_for_each_entry_in_dir(get_packed_ref_dir(packed_ref_cache
),
2197 0, write_packed_entry_fn
, out
);
2199 if (commit_lock_file(packed_ref_cache
->lock
)) {
2203 packed_ref_cache
->lock
= NULL
;
2204 release_packed_ref_cache(packed_ref_cache
);
2210 * Rollback the lockfile for the packed-refs file, and discard the
2211 * in-memory packed reference cache. (The packed-refs file will be
2212 * read anew if it is needed again after this function is called.)
2214 static void rollback_packed_refs(struct files_ref_store
*refs
)
2216 struct packed_ref_cache
*packed_ref_cache
=
2217 get_packed_ref_cache(refs
);
2219 assert_main_repository(&refs
->base
, "rollback_packed_refs");
2221 if (!packed_ref_cache
->lock
)
2222 die("internal error: packed-refs not locked");
2223 rollback_lock_file(packed_ref_cache
->lock
);
2224 packed_ref_cache
->lock
= NULL
;
2225 release_packed_ref_cache(packed_ref_cache
);
2226 clear_packed_ref_cache(refs
);
2229 struct ref_to_prune
{
2230 struct ref_to_prune
*next
;
2231 unsigned char sha1
[20];
2232 char name
[FLEX_ARRAY
];
2235 struct pack_refs_cb_data
{
2237 struct ref_dir
*packed_refs
;
2238 struct ref_to_prune
*ref_to_prune
;
2242 * An each_ref_entry_fn that is run over loose references only. If
2243 * the loose reference can be packed, add an entry in the packed ref
2244 * cache. If the reference should be pruned, also add it to
2245 * ref_to_prune in the pack_refs_cb_data.
2247 static int pack_if_possible_fn(struct ref_entry
*entry
, void *cb_data
)
2249 struct pack_refs_cb_data
*cb
= cb_data
;
2250 enum peel_status peel_status
;
2251 struct ref_entry
*packed_entry
;
2252 int is_tag_ref
= starts_with(entry
->name
, "refs/tags/");
2254 /* Do not pack per-worktree refs: */
2255 if (ref_type(entry
->name
) != REF_TYPE_NORMAL
)
2258 /* ALWAYS pack tags */
2259 if (!(cb
->flags
& PACK_REFS_ALL
) && !is_tag_ref
)
2262 /* Do not pack symbolic or broken refs: */
2263 if ((entry
->flag
& REF_ISSYMREF
) || !entry_resolves_to_object(entry
))
2266 /* Add a packed ref cache entry equivalent to the loose entry. */
2267 peel_status
= peel_entry(entry
, 1);
2268 if (peel_status
!= PEEL_PEELED
&& peel_status
!= PEEL_NON_TAG
)
2269 die("internal error peeling reference %s (%s)",
2270 entry
->name
, oid_to_hex(&entry
->u
.value
.oid
));
2271 packed_entry
= find_ref(cb
->packed_refs
, entry
->name
);
2273 /* Overwrite existing packed entry with info from loose entry */
2274 packed_entry
->flag
= REF_ISPACKED
| REF_KNOWS_PEELED
;
2275 oidcpy(&packed_entry
->u
.value
.oid
, &entry
->u
.value
.oid
);
2277 packed_entry
= create_ref_entry(entry
->name
, entry
->u
.value
.oid
.hash
,
2278 REF_ISPACKED
| REF_KNOWS_PEELED
, 0);
2279 add_ref(cb
->packed_refs
, packed_entry
);
2281 oidcpy(&packed_entry
->u
.value
.peeled
, &entry
->u
.value
.peeled
);
2283 /* Schedule the loose reference for pruning if requested. */
2284 if ((cb
->flags
& PACK_REFS_PRUNE
)) {
2285 struct ref_to_prune
*n
;
2286 FLEX_ALLOC_STR(n
, name
, entry
->name
);
2287 hashcpy(n
->sha1
, entry
->u
.value
.oid
.hash
);
2288 n
->next
= cb
->ref_to_prune
;
2289 cb
->ref_to_prune
= n
;
2295 * Remove empty parents, but spare refs/ and immediate subdirs.
2296 * Note: munges *name.
2298 static void try_remove_empty_parents(char *name
)
2303 for (i
= 0; i
< 2; i
++) { /* refs/{heads,tags,...}/ */
2304 while (*p
&& *p
!= '/')
2306 /* tolerate duplicate slashes; see check_refname_format() */
2310 for (q
= p
; *q
; q
++)
2313 while (q
> p
&& *q
!= '/')
2315 while (q
> p
&& *(q
-1) == '/')
2320 if (rmdir(git_path("%s", name
)))
2325 /* make sure nobody touched the ref, and unlink */
2326 static void prune_ref(struct ref_to_prune
*r
)
2328 struct ref_transaction
*transaction
;
2329 struct strbuf err
= STRBUF_INIT
;
2331 if (check_refname_format(r
->name
, 0))
2334 transaction
= ref_transaction_begin(&err
);
2336 ref_transaction_delete(transaction
, r
->name
, r
->sha1
,
2337 REF_ISPRUNING
| REF_NODEREF
, NULL
, &err
) ||
2338 ref_transaction_commit(transaction
, &err
)) {
2339 ref_transaction_free(transaction
);
2340 error("%s", err
.buf
);
2341 strbuf_release(&err
);
2344 ref_transaction_free(transaction
);
2345 strbuf_release(&err
);
2346 try_remove_empty_parents(r
->name
);
2349 static void prune_refs(struct ref_to_prune
*r
)
2357 int pack_refs(unsigned int flags
)
2359 struct files_ref_store
*refs
=
2360 get_files_ref_store(NULL
, "pack_refs");
2361 struct pack_refs_cb_data cbdata
;
2363 memset(&cbdata
, 0, sizeof(cbdata
));
2364 cbdata
.flags
= flags
;
2366 lock_packed_refs(refs
, LOCK_DIE_ON_ERROR
);
2367 cbdata
.packed_refs
= get_packed_refs(refs
);
2369 do_for_each_entry_in_dir(get_loose_refs(refs
), 0,
2370 pack_if_possible_fn
, &cbdata
);
2372 if (commit_packed_refs(refs
))
2373 die_errno("unable to overwrite old ref-pack file");
2375 prune_refs(cbdata
.ref_to_prune
);
2380 * Rewrite the packed-refs file, omitting any refs listed in
2381 * 'refnames'. On error, leave packed-refs unchanged, write an error
2382 * message to 'err', and return a nonzero value.
2384 * The refs in 'refnames' needn't be sorted. `err` must not be NULL.
2386 static int repack_without_refs(struct string_list
*refnames
, struct strbuf
*err
)
2388 struct files_ref_store
*refs
=
2389 get_files_ref_store(NULL
, "repack_without_refs");
2390 struct ref_dir
*packed
;
2391 struct string_list_item
*refname
;
2392 int ret
, needs_repacking
= 0, removed
= 0;
2396 /* Look for a packed ref */
2397 for_each_string_list_item(refname
, refnames
) {
2398 if (get_packed_ref(refs
, refname
->string
)) {
2399 needs_repacking
= 1;
2404 /* Avoid locking if we have nothing to do */
2405 if (!needs_repacking
)
2406 return 0; /* no refname exists in packed refs */
2408 if (lock_packed_refs(refs
, 0)) {
2409 unable_to_lock_message(git_path("packed-refs"), errno
, err
);
2412 packed
= get_packed_refs(refs
);
2414 /* Remove refnames from the cache */
2415 for_each_string_list_item(refname
, refnames
)
2416 if (remove_entry(packed
, refname
->string
) != -1)
2420 * All packed entries disappeared while we were
2421 * acquiring the lock.
2423 rollback_packed_refs(refs
);
2427 /* Write what remains */
2428 ret
= commit_packed_refs(refs
);
2430 strbuf_addf(err
, "unable to overwrite old ref-pack file: %s",
2435 static int delete_ref_loose(struct ref_lock
*lock
, int flag
, struct strbuf
*err
)
2439 if (!(flag
& REF_ISPACKED
) || flag
& REF_ISSYMREF
) {
2441 * loose. The loose file name is the same as the
2442 * lockfile name, minus ".lock":
2444 char *loose_filename
= get_locked_file_path(lock
->lk
);
2445 int res
= unlink_or_msg(loose_filename
, err
);
2446 free(loose_filename
);
2453 int delete_refs(struct string_list
*refnames
, unsigned int flags
)
2455 struct strbuf err
= STRBUF_INIT
;
2461 result
= repack_without_refs(refnames
, &err
);
2464 * If we failed to rewrite the packed-refs file, then
2465 * it is unsafe to try to remove loose refs, because
2466 * doing so might expose an obsolete packed value for
2467 * a reference that might even point at an object that
2468 * has been garbage collected.
2470 if (refnames
->nr
== 1)
2471 error(_("could not delete reference %s: %s"),
2472 refnames
->items
[0].string
, err
.buf
);
2474 error(_("could not delete references: %s"), err
.buf
);
2479 for (i
= 0; i
< refnames
->nr
; i
++) {
2480 const char *refname
= refnames
->items
[i
].string
;
2482 if (delete_ref(refname
, NULL
, flags
))
2483 result
|= error(_("could not remove reference %s"), refname
);
2487 strbuf_release(&err
);
2492 * People using contrib's git-new-workdir have .git/logs/refs ->
2493 * /some/other/path/.git/logs/refs, and that may live on another device.
2495 * IOW, to avoid cross device rename errors, the temporary renamed log must
2496 * live into logs/refs.
2498 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
2500 static int rename_tmp_log(const char *newrefname
)
2502 int attempts_remaining
= 4;
2503 struct strbuf path
= STRBUF_INIT
;
2507 strbuf_reset(&path
);
2508 strbuf_git_path(&path
, "logs/%s", newrefname
);
2509 switch (safe_create_leading_directories_const(path
.buf
)) {
2511 break; /* success */
2513 if (--attempts_remaining
> 0)
2517 error("unable to create directory for %s", newrefname
);
2521 if (rename(git_path(TMP_RENAMED_LOG
), path
.buf
)) {
2522 if ((errno
==EISDIR
|| errno
==ENOTDIR
) && --attempts_remaining
> 0) {
2524 * rename(a, b) when b is an existing
2525 * directory ought to result in ISDIR, but
2526 * Solaris 5.8 gives ENOTDIR. Sheesh.
2528 if (remove_empty_directories(&path
)) {
2529 error("Directory not empty: logs/%s", newrefname
);
2533 } else if (errno
== ENOENT
&& --attempts_remaining
> 0) {
2535 * Maybe another process just deleted one of
2536 * the directories in the path to newrefname.
2537 * Try again from the beginning.
2541 error("unable to move logfile "TMP_RENAMED_LOG
" to logs/%s: %s",
2542 newrefname
, strerror(errno
));
2548 strbuf_release(&path
);
2552 int verify_refname_available(const char *newname
,
2553 const struct string_list
*extras
,
2554 const struct string_list
*skip
,
2557 struct files_ref_store
*refs
=
2558 get_files_ref_store(NULL
, "verify_refname_available");
2559 struct ref_dir
*packed_refs
= get_packed_refs(refs
);
2560 struct ref_dir
*loose_refs
= get_loose_refs(refs
);
2562 if (verify_refname_available_dir(newname
, extras
, skip
,
2563 packed_refs
, err
) ||
2564 verify_refname_available_dir(newname
, extras
, skip
,
2571 static int write_ref_to_lockfile(struct ref_lock
*lock
,
2572 const unsigned char *sha1
, struct strbuf
*err
);
2573 static int commit_ref_update(struct ref_lock
*lock
,
2574 const unsigned char *sha1
, const char *logmsg
,
2575 struct strbuf
*err
);
2577 int rename_ref(const char *oldrefname
, const char *newrefname
, const char *logmsg
)
2579 unsigned char sha1
[20], orig_sha1
[20];
2580 int flag
= 0, logmoved
= 0;
2581 struct ref_lock
*lock
;
2582 struct stat loginfo
;
2583 int log
= !lstat(git_path("logs/%s", oldrefname
), &loginfo
);
2584 struct strbuf err
= STRBUF_INIT
;
2586 if (log
&& S_ISLNK(loginfo
.st_mode
))
2587 return error("reflog for %s is a symlink", oldrefname
);
2589 if (!resolve_ref_unsafe(oldrefname
, RESOLVE_REF_READING
| RESOLVE_REF_NO_RECURSE
,
2591 return error("refname %s not found", oldrefname
);
2593 if (flag
& REF_ISSYMREF
)
2594 return error("refname %s is a symbolic ref, renaming it is not supported",
2596 if (!rename_ref_available(oldrefname
, newrefname
))
2599 if (log
&& rename(git_path("logs/%s", oldrefname
), git_path(TMP_RENAMED_LOG
)))
2600 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG
": %s",
2601 oldrefname
, strerror(errno
));
2603 if (delete_ref(oldrefname
, orig_sha1
, REF_NODEREF
)) {
2604 error("unable to delete old %s", oldrefname
);
2609 * Since we are doing a shallow lookup, sha1 is not the
2610 * correct value to pass to delete_ref as old_sha1. But that
2611 * doesn't matter, because an old_sha1 check wouldn't add to
2612 * the safety anyway; we want to delete the reference whatever
2613 * its current value.
2615 if (!read_ref_full(newrefname
, RESOLVE_REF_READING
| RESOLVE_REF_NO_RECURSE
,
2617 delete_ref(newrefname
, NULL
, REF_NODEREF
)) {
2618 if (errno
==EISDIR
) {
2619 struct strbuf path
= STRBUF_INIT
;
2622 strbuf_git_path(&path
, "%s", newrefname
);
2623 result
= remove_empty_directories(&path
);
2624 strbuf_release(&path
);
2627 error("Directory not empty: %s", newrefname
);
2631 error("unable to delete existing %s", newrefname
);
2636 if (log
&& rename_tmp_log(newrefname
))
2641 lock
= lock_ref_sha1_basic(newrefname
, NULL
, NULL
, NULL
, REF_NODEREF
,
2644 error("unable to rename '%s' to '%s': %s", oldrefname
, newrefname
, err
.buf
);
2645 strbuf_release(&err
);
2648 hashcpy(lock
->old_oid
.hash
, orig_sha1
);
2650 if (write_ref_to_lockfile(lock
, orig_sha1
, &err
) ||
2651 commit_ref_update(lock
, orig_sha1
, logmsg
, &err
)) {
2652 error("unable to write current sha1 into %s: %s", newrefname
, err
.buf
);
2653 strbuf_release(&err
);
2660 lock
= lock_ref_sha1_basic(oldrefname
, NULL
, NULL
, NULL
, REF_NODEREF
,
2663 error("unable to lock %s for rollback: %s", oldrefname
, err
.buf
);
2664 strbuf_release(&err
);
2668 flag
= log_all_ref_updates
;
2669 log_all_ref_updates
= 0;
2670 if (write_ref_to_lockfile(lock
, orig_sha1
, &err
) ||
2671 commit_ref_update(lock
, orig_sha1
, NULL
, &err
)) {
2672 error("unable to write current sha1 into %s: %s", oldrefname
, err
.buf
);
2673 strbuf_release(&err
);
2675 log_all_ref_updates
= flag
;
2678 if (logmoved
&& rename(git_path("logs/%s", newrefname
), git_path("logs/%s", oldrefname
)))
2679 error("unable to restore logfile %s from %s: %s",
2680 oldrefname
, newrefname
, strerror(errno
));
2681 if (!logmoved
&& log
&&
2682 rename(git_path(TMP_RENAMED_LOG
), git_path("logs/%s", oldrefname
)))
2683 error("unable to restore logfile %s from "TMP_RENAMED_LOG
": %s",
2684 oldrefname
, strerror(errno
));
2689 static int close_ref(struct ref_lock
*lock
)
2691 if (close_lock_file(lock
->lk
))
2696 static int commit_ref(struct ref_lock
*lock
)
2698 char *path
= get_locked_file_path(lock
->lk
);
2701 if (!lstat(path
, &st
) && S_ISDIR(st
.st_mode
)) {
2703 * There is a directory at the path we want to rename
2704 * the lockfile to. Hopefully it is empty; try to
2707 size_t len
= strlen(path
);
2708 struct strbuf sb_path
= STRBUF_INIT
;
2710 strbuf_attach(&sb_path
, path
, len
, len
);
2713 * If this fails, commit_lock_file() will also fail
2714 * and will report the problem.
2716 remove_empty_directories(&sb_path
);
2717 strbuf_release(&sb_path
);
2722 if (commit_lock_file(lock
->lk
))
2728 * Create a reflog for a ref. If force_create = 0, the reflog will
2729 * only be created for certain refs (those for which
2730 * should_autocreate_reflog returns non-zero. Otherwise, create it
2731 * regardless of the ref name. Fill in *err and return -1 on failure.
2733 static int log_ref_setup(const char *refname
, struct strbuf
*logfile
, struct strbuf
*err
, int force_create
)
2735 int logfd
, oflags
= O_APPEND
| O_WRONLY
;
2737 strbuf_git_path(logfile
, "logs/%s", refname
);
2738 if (force_create
|| should_autocreate_reflog(refname
)) {
2739 if (safe_create_leading_directories(logfile
->buf
) < 0) {
2740 strbuf_addf(err
, "unable to create directory for '%s': "
2741 "%s", logfile
->buf
, strerror(errno
));
2747 logfd
= open(logfile
->buf
, oflags
, 0666);
2749 if (!(oflags
& O_CREAT
) && (errno
== ENOENT
|| errno
== EISDIR
))
2752 if (errno
== EISDIR
) {
2753 if (remove_empty_directories(logfile
)) {
2754 strbuf_addf(err
, "there are still logs under "
2755 "'%s'", logfile
->buf
);
2758 logfd
= open(logfile
->buf
, oflags
, 0666);
2762 strbuf_addf(err
, "unable to append to '%s': %s",
2763 logfile
->buf
, strerror(errno
));
2768 adjust_shared_perm(logfile
->buf
);
2774 int safe_create_reflog(const char *refname
, int force_create
, struct strbuf
*err
)
2777 struct strbuf sb
= STRBUF_INIT
;
2779 ret
= log_ref_setup(refname
, &sb
, err
, force_create
);
2780 strbuf_release(&sb
);
2784 static int log_ref_write_fd(int fd
, const unsigned char *old_sha1
,
2785 const unsigned char *new_sha1
,
2786 const char *committer
, const char *msg
)
2788 int msglen
, written
;
2789 unsigned maxlen
, len
;
2792 msglen
= msg
? strlen(msg
) : 0;
2793 maxlen
= strlen(committer
) + msglen
+ 100;
2794 logrec
= xmalloc(maxlen
);
2795 len
= xsnprintf(logrec
, maxlen
, "%s %s %s\n",
2796 sha1_to_hex(old_sha1
),
2797 sha1_to_hex(new_sha1
),
2800 len
+= copy_reflog_msg(logrec
+ len
- 1, msg
) - 1;
2802 written
= len
<= maxlen
? write_in_full(fd
, logrec
, len
) : -1;
2810 static int log_ref_write_1(const char *refname
, const unsigned char *old_sha1
,
2811 const unsigned char *new_sha1
, const char *msg
,
2812 struct strbuf
*logfile
, int flags
,
2815 int logfd
, result
, oflags
= O_APPEND
| O_WRONLY
;
2817 if (log_all_ref_updates
< 0)
2818 log_all_ref_updates
= !is_bare_repository();
2820 result
= log_ref_setup(refname
, logfile
, err
, flags
& REF_FORCE_CREATE_REFLOG
);
2825 logfd
= open(logfile
->buf
, oflags
);
2828 result
= log_ref_write_fd(logfd
, old_sha1
, new_sha1
,
2829 git_committer_info(0), msg
);
2831 strbuf_addf(err
, "unable to append to '%s': %s", logfile
->buf
,
2837 strbuf_addf(err
, "unable to append to '%s': %s", logfile
->buf
,
2844 static int log_ref_write(const char *refname
, const unsigned char *old_sha1
,
2845 const unsigned char *new_sha1
, const char *msg
,
2846 int flags
, struct strbuf
*err
)
2848 return files_log_ref_write(refname
, old_sha1
, new_sha1
, msg
, flags
,
2852 int files_log_ref_write(const char *refname
, const unsigned char *old_sha1
,
2853 const unsigned char *new_sha1
, const char *msg
,
2854 int flags
, struct strbuf
*err
)
2856 struct strbuf sb
= STRBUF_INIT
;
2857 int ret
= log_ref_write_1(refname
, old_sha1
, new_sha1
, msg
, &sb
, flags
,
2859 strbuf_release(&sb
);
2864 * Write sha1 into the open lockfile, then close the lockfile. On
2865 * errors, rollback the lockfile, fill in *err and
2868 static int write_ref_to_lockfile(struct ref_lock
*lock
,
2869 const unsigned char *sha1
, struct strbuf
*err
)
2871 static char term
= '\n';
2875 o
= parse_object(sha1
);
2878 "trying to write ref '%s' with nonexistent object %s",
2879 lock
->ref_name
, sha1_to_hex(sha1
));
2883 if (o
->type
!= OBJ_COMMIT
&& is_branch(lock
->ref_name
)) {
2885 "trying to write non-commit object %s to branch '%s'",
2886 sha1_to_hex(sha1
), lock
->ref_name
);
2890 fd
= get_lock_file_fd(lock
->lk
);
2891 if (write_in_full(fd
, sha1_to_hex(sha1
), 40) != 40 ||
2892 write_in_full(fd
, &term
, 1) != 1 ||
2893 close_ref(lock
) < 0) {
2895 "couldn't write '%s'", get_lock_file_path(lock
->lk
));
2903 * Commit a change to a loose reference that has already been written
2904 * to the loose reference lockfile. Also update the reflogs if
2905 * necessary, using the specified lockmsg (which can be NULL).
2907 static int commit_ref_update(struct ref_lock
*lock
,
2908 const unsigned char *sha1
, const char *logmsg
,
2911 struct files_ref_store
*refs
=
2912 get_files_ref_store(NULL
, "commit_ref_update");
2914 clear_loose_ref_cache(refs
);
2915 if (log_ref_write(lock
->ref_name
, lock
->old_oid
.hash
, sha1
, logmsg
, 0, err
)) {
2916 char *old_msg
= strbuf_detach(err
, NULL
);
2917 strbuf_addf(err
, "cannot update the ref '%s': %s",
2918 lock
->ref_name
, old_msg
);
2924 if (strcmp(lock
->ref_name
, "HEAD") != 0) {
2926 * Special hack: If a branch is updated directly and HEAD
2927 * points to it (may happen on the remote side of a push
2928 * for example) then logically the HEAD reflog should be
2930 * A generic solution implies reverse symref information,
2931 * but finding all symrefs pointing to the given branch
2932 * would be rather costly for this rare event (the direct
2933 * update of a branch) to be worth it. So let's cheat and
2934 * check with HEAD only which should cover 99% of all usage
2935 * scenarios (even 100% of the default ones).
2937 unsigned char head_sha1
[20];
2939 const char *head_ref
;
2941 head_ref
= resolve_ref_unsafe("HEAD", RESOLVE_REF_READING
,
2942 head_sha1
, &head_flag
);
2943 if (head_ref
&& (head_flag
& REF_ISSYMREF
) &&
2944 !strcmp(head_ref
, lock
->ref_name
)) {
2945 struct strbuf log_err
= STRBUF_INIT
;
2946 if (log_ref_write("HEAD", lock
->old_oid
.hash
, sha1
,
2947 logmsg
, 0, &log_err
)) {
2948 error("%s", log_err
.buf
);
2949 strbuf_release(&log_err
);
2954 if (commit_ref(lock
)) {
2955 strbuf_addf(err
, "couldn't set '%s'", lock
->ref_name
);
2964 static int create_ref_symlink(struct ref_lock
*lock
, const char *target
)
2967 #ifndef NO_SYMLINK_HEAD
2968 char *ref_path
= get_locked_file_path(lock
->lk
);
2970 ret
= symlink(target
, ref_path
);
2974 fprintf(stderr
, "no symlink - falling back to symbolic ref\n");
2979 static void update_symref_reflog(struct ref_lock
*lock
, const char *refname
,
2980 const char *target
, const char *logmsg
)
2982 struct strbuf err
= STRBUF_INIT
;
2983 unsigned char new_sha1
[20];
2984 if (logmsg
&& !read_ref(target
, new_sha1
) &&
2985 log_ref_write(refname
, lock
->old_oid
.hash
, new_sha1
, logmsg
, 0, &err
)) {
2986 error("%s", err
.buf
);
2987 strbuf_release(&err
);
2991 static int create_symref_locked(struct ref_lock
*lock
, const char *refname
,
2992 const char *target
, const char *logmsg
)
2994 if (prefer_symlink_refs
&& !create_ref_symlink(lock
, target
)) {
2995 update_symref_reflog(lock
, refname
, target
, logmsg
);
2999 if (!fdopen_lock_file(lock
->lk
, "w"))
3000 return error("unable to fdopen %s: %s",
3001 lock
->lk
->tempfile
.filename
.buf
, strerror(errno
));
3003 update_symref_reflog(lock
, refname
, target
, logmsg
);
3005 /* no error check; commit_ref will check ferror */
3006 fprintf(lock
->lk
->tempfile
.fp
, "ref: %s\n", target
);
3007 if (commit_ref(lock
) < 0)
3008 return error("unable to write symref for %s: %s", refname
,
3013 int create_symref(const char *refname
, const char *target
, const char *logmsg
)
3015 struct strbuf err
= STRBUF_INIT
;
3016 struct ref_lock
*lock
;
3019 lock
= lock_ref_sha1_basic(refname
, NULL
, NULL
, NULL
, REF_NODEREF
, NULL
,
3022 error("%s", err
.buf
);
3023 strbuf_release(&err
);
3027 ret
= create_symref_locked(lock
, refname
, target
, logmsg
);
3032 int set_worktree_head_symref(const char *gitdir
, const char *target
)
3034 static struct lock_file head_lock
;
3035 struct ref_lock
*lock
;
3036 struct strbuf head_path
= STRBUF_INIT
;
3037 const char *head_rel
;
3040 strbuf_addf(&head_path
, "%s/HEAD", absolute_path(gitdir
));
3041 if (hold_lock_file_for_update(&head_lock
, head_path
.buf
,
3042 LOCK_NO_DEREF
) < 0) {
3043 struct strbuf err
= STRBUF_INIT
;
3044 unable_to_lock_message(head_path
.buf
, errno
, &err
);
3045 error("%s", err
.buf
);
3046 strbuf_release(&err
);
3047 strbuf_release(&head_path
);
3051 /* head_rel will be "HEAD" for the main tree, "worktrees/wt/HEAD" for
3053 head_rel
= remove_leading_path(head_path
.buf
,
3054 absolute_path(get_git_common_dir()));
3055 /* to make use of create_symref_locked(), initialize ref_lock */
3056 lock
= xcalloc(1, sizeof(struct ref_lock
));
3057 lock
->lk
= &head_lock
;
3058 lock
->ref_name
= xstrdup(head_rel
);
3060 ret
= create_symref_locked(lock
, head_rel
, target
, NULL
);
3062 unlock_ref(lock
); /* will free lock */
3063 strbuf_release(&head_path
);
3067 int reflog_exists(const char *refname
)
3071 return !lstat(git_path("logs/%s", refname
), &st
) &&
3072 S_ISREG(st
.st_mode
);
3075 int delete_reflog(const char *refname
)
3077 return remove_path(git_path("logs/%s", refname
));
3080 static int show_one_reflog_ent(struct strbuf
*sb
, each_reflog_ent_fn fn
, void *cb_data
)
3082 unsigned char osha1
[20], nsha1
[20];
3083 char *email_end
, *message
;
3084 unsigned long timestamp
;
3087 /* old SP new SP name <email> SP time TAB msg LF */
3088 if (sb
->len
< 83 || sb
->buf
[sb
->len
- 1] != '\n' ||
3089 get_sha1_hex(sb
->buf
, osha1
) || sb
->buf
[40] != ' ' ||
3090 get_sha1_hex(sb
->buf
+ 41, nsha1
) || sb
->buf
[81] != ' ' ||
3091 !(email_end
= strchr(sb
->buf
+ 82, '>')) ||
3092 email_end
[1] != ' ' ||
3093 !(timestamp
= strtoul(email_end
+ 2, &message
, 10)) ||
3094 !message
|| message
[0] != ' ' ||
3095 (message
[1] != '+' && message
[1] != '-') ||
3096 !isdigit(message
[2]) || !isdigit(message
[3]) ||
3097 !isdigit(message
[4]) || !isdigit(message
[5]))
3098 return 0; /* corrupt? */
3099 email_end
[1] = '\0';
3100 tz
= strtol(message
+ 1, NULL
, 10);
3101 if (message
[6] != '\t')
3105 return fn(osha1
, nsha1
, sb
->buf
+ 82, timestamp
, tz
, message
, cb_data
);
3108 static char *find_beginning_of_line(char *bob
, char *scan
)
3110 while (bob
< scan
&& *(--scan
) != '\n')
3111 ; /* keep scanning backwards */
3113 * Return either beginning of the buffer, or LF at the end of
3114 * the previous line.
3119 int for_each_reflog_ent_reverse(const char *refname
, each_reflog_ent_fn fn
, void *cb_data
)
3121 struct strbuf sb
= STRBUF_INIT
;
3124 int ret
= 0, at_tail
= 1;
3126 logfp
= fopen(git_path("logs/%s", refname
), "r");
3130 /* Jump to the end */
3131 if (fseek(logfp
, 0, SEEK_END
) < 0)
3132 return error("cannot seek back reflog for %s: %s",
3133 refname
, strerror(errno
));
3135 while (!ret
&& 0 < pos
) {
3141 /* Fill next block from the end */
3142 cnt
= (sizeof(buf
) < pos
) ? sizeof(buf
) : pos
;
3143 if (fseek(logfp
, pos
- cnt
, SEEK_SET
))
3144 return error("cannot seek back reflog for %s: %s",
3145 refname
, strerror(errno
));
3146 nread
= fread(buf
, cnt
, 1, logfp
);
3148 return error("cannot read %d bytes from reflog for %s: %s",
3149 cnt
, refname
, strerror(errno
));
3152 scanp
= endp
= buf
+ cnt
;
3153 if (at_tail
&& scanp
[-1] == '\n')
3154 /* Looking at the final LF at the end of the file */
3158 while (buf
< scanp
) {
3160 * terminating LF of the previous line, or the beginning
3165 bp
= find_beginning_of_line(buf
, scanp
);
3169 * The newline is the end of the previous line,
3170 * so we know we have complete line starting
3171 * at (bp + 1). Prefix it onto any prior data
3172 * we collected for the line and process it.
3174 strbuf_splice(&sb
, 0, 0, bp
+ 1, endp
- (bp
+ 1));
3177 ret
= show_one_reflog_ent(&sb
, fn
, cb_data
);
3183 * We are at the start of the buffer, and the
3184 * start of the file; there is no previous
3185 * line, and we have everything for this one.
3186 * Process it, and we can end the loop.
3188 strbuf_splice(&sb
, 0, 0, buf
, endp
- buf
);
3189 ret
= show_one_reflog_ent(&sb
, fn
, cb_data
);
3196 * We are at the start of the buffer, and there
3197 * is more file to read backwards. Which means
3198 * we are in the middle of a line. Note that we
3199 * may get here even if *bp was a newline; that
3200 * just means we are at the exact end of the
3201 * previous line, rather than some spot in the
3204 * Save away what we have to be combined with
3205 * the data from the next read.
3207 strbuf_splice(&sb
, 0, 0, buf
, endp
- buf
);
3214 die("BUG: reverse reflog parser had leftover data");
3217 strbuf_release(&sb
);
3221 int for_each_reflog_ent(const char *refname
, each_reflog_ent_fn fn
, void *cb_data
)
3224 struct strbuf sb
= STRBUF_INIT
;
3227 logfp
= fopen(git_path("logs/%s", refname
), "r");
3231 while (!ret
&& !strbuf_getwholeline(&sb
, logfp
, '\n'))
3232 ret
= show_one_reflog_ent(&sb
, fn
, cb_data
);
3234 strbuf_release(&sb
);
3238 struct files_reflog_iterator
{
3239 struct ref_iterator base
;
3241 struct dir_iterator
*dir_iterator
;
3242 struct object_id oid
;
3245 static int files_reflog_iterator_advance(struct ref_iterator
*ref_iterator
)
3247 struct files_reflog_iterator
*iter
=
3248 (struct files_reflog_iterator
*)ref_iterator
;
3249 struct dir_iterator
*diter
= iter
->dir_iterator
;
3252 while ((ok
= dir_iterator_advance(diter
)) == ITER_OK
) {
3255 if (!S_ISREG(diter
->st
.st_mode
))
3257 if (diter
->basename
[0] == '.')
3259 if (ends_with(diter
->basename
, ".lock"))
3262 if (read_ref_full(diter
->relative_path
, 0,
3263 iter
->oid
.hash
, &flags
)) {
3264 error("bad ref for %s", diter
->path
.buf
);
3268 iter
->base
.refname
= diter
->relative_path
;
3269 iter
->base
.oid
= &iter
->oid
;
3270 iter
->base
.flags
= flags
;
3274 iter
->dir_iterator
= NULL
;
3275 if (ref_iterator_abort(ref_iterator
) == ITER_ERROR
)
3280 static int files_reflog_iterator_peel(struct ref_iterator
*ref_iterator
,
3281 struct object_id
*peeled
)
3283 die("BUG: ref_iterator_peel() called for reflog_iterator");
3286 static int files_reflog_iterator_abort(struct ref_iterator
*ref_iterator
)
3288 struct files_reflog_iterator
*iter
=
3289 (struct files_reflog_iterator
*)ref_iterator
;
3292 if (iter
->dir_iterator
)
3293 ok
= dir_iterator_abort(iter
->dir_iterator
);
3295 base_ref_iterator_free(ref_iterator
);
3299 static struct ref_iterator_vtable files_reflog_iterator_vtable
= {
3300 files_reflog_iterator_advance
,
3301 files_reflog_iterator_peel
,
3302 files_reflog_iterator_abort
3305 struct ref_iterator
*files_reflog_iterator_begin(void)
3307 struct files_reflog_iterator
*iter
= xcalloc(1, sizeof(*iter
));
3308 struct ref_iterator
*ref_iterator
= &iter
->base
;
3310 base_ref_iterator_init(ref_iterator
, &files_reflog_iterator_vtable
);
3311 iter
->dir_iterator
= dir_iterator_begin(git_path("logs"));
3312 return ref_iterator
;
3315 int for_each_reflog(each_ref_fn fn
, void *cb_data
)
3317 return do_for_each_ref_iterator(files_reflog_iterator_begin(),
3321 static int ref_update_reject_duplicates(struct string_list
*refnames
,
3324 int i
, n
= refnames
->nr
;
3328 for (i
= 1; i
< n
; i
++)
3329 if (!strcmp(refnames
->items
[i
- 1].string
, refnames
->items
[i
].string
)) {
3331 "multiple updates for ref '%s' not allowed.",
3332 refnames
->items
[i
].string
);
3339 * If update is a direct update of head_ref (the reference pointed to
3340 * by HEAD), then add an extra REF_LOG_ONLY update for HEAD.
3342 static int split_head_update(struct ref_update
*update
,
3343 struct ref_transaction
*transaction
,
3344 const char *head_ref
,
3345 struct string_list
*affected_refnames
,
3348 struct string_list_item
*item
;
3349 struct ref_update
*new_update
;
3351 if ((update
->flags
& REF_LOG_ONLY
) ||
3352 (update
->flags
& REF_ISPRUNING
) ||
3353 (update
->flags
& REF_UPDATE_VIA_HEAD
))
3356 if (strcmp(update
->refname
, head_ref
))
3360 * First make sure that HEAD is not already in the
3361 * transaction. This insertion is O(N) in the transaction
3362 * size, but it happens at most once per transaction.
3364 item
= string_list_insert(affected_refnames
, "HEAD");
3366 /* An entry already existed */
3368 "multiple updates for 'HEAD' (including one "
3369 "via its referent '%s') are not allowed",
3371 return TRANSACTION_NAME_CONFLICT
;
3374 new_update
= ref_transaction_add_update(
3375 transaction
, "HEAD",
3376 update
->flags
| REF_LOG_ONLY
| REF_NODEREF
,
3377 update
->new_sha1
, update
->old_sha1
,
3380 item
->util
= new_update
;
3386 * update is for a symref that points at referent and doesn't have
3387 * REF_NODEREF set. Split it into two updates:
3388 * - The original update, but with REF_LOG_ONLY and REF_NODEREF set
3389 * - A new, separate update for the referent reference
3390 * Note that the new update will itself be subject to splitting when
3391 * the iteration gets to it.
3393 static int split_symref_update(struct ref_update
*update
,
3394 const char *referent
,
3395 struct ref_transaction
*transaction
,
3396 struct string_list
*affected_refnames
,
3399 struct string_list_item
*item
;
3400 struct ref_update
*new_update
;
3401 unsigned int new_flags
;
3404 * First make sure that referent is not already in the
3405 * transaction. This insertion is O(N) in the transaction
3406 * size, but it happens at most once per symref in a
3409 item
= string_list_insert(affected_refnames
, referent
);
3411 /* An entry already existed */
3413 "multiple updates for '%s' (including one "
3414 "via symref '%s') are not allowed",
3415 referent
, update
->refname
);
3416 return TRANSACTION_NAME_CONFLICT
;
3419 new_flags
= update
->flags
;
3420 if (!strcmp(update
->refname
, "HEAD")) {
3422 * Record that the new update came via HEAD, so that
3423 * when we process it, split_head_update() doesn't try
3424 * to add another reflog update for HEAD. Note that
3425 * this bit will be propagated if the new_update
3426 * itself needs to be split.
3428 new_flags
|= REF_UPDATE_VIA_HEAD
;
3431 new_update
= ref_transaction_add_update(
3432 transaction
, referent
, new_flags
,
3433 update
->new_sha1
, update
->old_sha1
,
3436 new_update
->parent_update
= update
;
3439 * Change the symbolic ref update to log only. Also, it
3440 * doesn't need to check its old SHA-1 value, as that will be
3441 * done when new_update is processed.
3443 update
->flags
|= REF_LOG_ONLY
| REF_NODEREF
;
3444 update
->flags
&= ~REF_HAVE_OLD
;
3446 item
->util
= new_update
;
3452 * Return the refname under which update was originally requested.
3454 static const char *original_update_refname(struct ref_update
*update
)
3456 while (update
->parent_update
)
3457 update
= update
->parent_update
;
3459 return update
->refname
;
3463 * Prepare for carrying out update:
3464 * - Lock the reference referred to by update.
3465 * - Read the reference under lock.
3466 * - Check that its old SHA-1 value (if specified) is correct, and in
3467 * any case record it in update->lock->old_oid for later use when
3468 * writing the reflog.
3469 * - If it is a symref update without REF_NODEREF, split it up into a
3470 * REF_LOG_ONLY update of the symref and add a separate update for
3471 * the referent to transaction.
3472 * - If it is an update of head_ref, add a corresponding REF_LOG_ONLY
3475 static int lock_ref_for_update(struct ref_update
*update
,
3476 struct ref_transaction
*transaction
,
3477 const char *head_ref
,
3478 struct string_list
*affected_refnames
,
3481 struct strbuf referent
= STRBUF_INIT
;
3482 int mustexist
= (update
->flags
& REF_HAVE_OLD
) &&
3483 !is_null_sha1(update
->old_sha1
);
3485 struct ref_lock
*lock
;
3487 if ((update
->flags
& REF_HAVE_NEW
) && is_null_sha1(update
->new_sha1
))
3488 update
->flags
|= REF_DELETING
;
3491 ret
= split_head_update(update
, transaction
, head_ref
,
3492 affected_refnames
, err
);
3497 ret
= lock_raw_ref(update
->refname
, mustexist
,
3498 affected_refnames
, NULL
,
3499 &update
->lock
, &referent
,
3500 &update
->type
, err
);
3505 reason
= strbuf_detach(err
, NULL
);
3506 strbuf_addf(err
, "cannot lock ref '%s': %s",
3507 update
->refname
, reason
);
3512 lock
= update
->lock
;
3514 if (update
->type
& REF_ISSYMREF
) {
3515 if (update
->flags
& REF_NODEREF
) {
3517 * We won't be reading the referent as part of
3518 * the transaction, so we have to read it here
3519 * to record and possibly check old_sha1:
3521 if (read_ref_full(update
->refname
,
3522 mustexist
? RESOLVE_REF_READING
: 0,
3523 lock
->old_oid
.hash
, NULL
)) {
3524 if (update
->flags
& REF_HAVE_OLD
) {
3525 strbuf_addf(err
, "cannot lock ref '%s': "
3526 "can't resolve old value",
3528 return TRANSACTION_GENERIC_ERROR
;
3530 hashclr(lock
->old_oid
.hash
);
3533 if ((update
->flags
& REF_HAVE_OLD
) &&
3534 hashcmp(lock
->old_oid
.hash
, update
->old_sha1
)) {
3535 strbuf_addf(err
, "cannot lock ref '%s': "
3536 "is at %s but expected %s",
3538 sha1_to_hex(lock
->old_oid
.hash
),
3539 sha1_to_hex(update
->old_sha1
));
3540 return TRANSACTION_GENERIC_ERROR
;
3545 * Create a new update for the reference this
3546 * symref is pointing at. Also, we will record
3547 * and verify old_sha1 for this update as part
3548 * of processing the split-off update, so we
3549 * don't have to do it here.
3551 ret
= split_symref_update(update
, referent
.buf
, transaction
,
3552 affected_refnames
, err
);
3557 struct ref_update
*parent_update
;
3560 * If this update is happening indirectly because of a
3561 * symref update, record the old SHA-1 in the parent
3564 for (parent_update
= update
->parent_update
;
3566 parent_update
= parent_update
->parent_update
) {
3567 oidcpy(&parent_update
->lock
->old_oid
, &lock
->old_oid
);
3570 if ((update
->flags
& REF_HAVE_OLD
) &&
3571 hashcmp(lock
->old_oid
.hash
, update
->old_sha1
)) {
3572 if (is_null_sha1(update
->old_sha1
))
3573 strbuf_addf(err
, "cannot lock ref '%s': reference already exists",
3574 original_update_refname(update
));
3576 strbuf_addf(err
, "cannot lock ref '%s': is at %s but expected %s",
3577 original_update_refname(update
),
3578 sha1_to_hex(lock
->old_oid
.hash
),
3579 sha1_to_hex(update
->old_sha1
));
3581 return TRANSACTION_GENERIC_ERROR
;
3585 if ((update
->flags
& REF_HAVE_NEW
) &&
3586 !(update
->flags
& REF_DELETING
) &&
3587 !(update
->flags
& REF_LOG_ONLY
)) {
3588 if (!(update
->type
& REF_ISSYMREF
) &&
3589 !hashcmp(lock
->old_oid
.hash
, update
->new_sha1
)) {
3591 * The reference already has the desired
3592 * value, so we don't need to write it.
3594 } else if (write_ref_to_lockfile(lock
, update
->new_sha1
,
3596 char *write_err
= strbuf_detach(err
, NULL
);
3599 * The lock was freed upon failure of
3600 * write_ref_to_lockfile():
3602 update
->lock
= NULL
;
3604 "cannot update the ref '%s': %s",
3605 update
->refname
, write_err
);
3607 return TRANSACTION_GENERIC_ERROR
;
3609 update
->flags
|= REF_NEEDS_COMMIT
;
3612 if (!(update
->flags
& REF_NEEDS_COMMIT
)) {
3614 * We didn't call write_ref_to_lockfile(), so
3615 * the lockfile is still open. Close it to
3616 * free up the file descriptor:
3618 if (close_ref(lock
)) {
3619 strbuf_addf(err
, "couldn't close '%s.lock'",
3621 return TRANSACTION_GENERIC_ERROR
;
3627 static int files_transaction_commit(struct ref_store
*ref_store
,
3628 struct ref_transaction
*transaction
,
3631 struct files_ref_store
*refs
=
3632 files_downcast(ref_store
, 0, "ref_transaction_commit");
3634 struct string_list refs_to_delete
= STRING_LIST_INIT_NODUP
;
3635 struct string_list_item
*ref_to_delete
;
3636 struct string_list affected_refnames
= STRING_LIST_INIT_NODUP
;
3637 char *head_ref
= NULL
;
3639 struct object_id head_oid
;
3643 if (transaction
->state
!= REF_TRANSACTION_OPEN
)
3644 die("BUG: commit called for transaction that is not open");
3646 if (!transaction
->nr
) {
3647 transaction
->state
= REF_TRANSACTION_CLOSED
;
3652 * Fail if a refname appears more than once in the
3653 * transaction. (If we end up splitting up any updates using
3654 * split_symref_update() or split_head_update(), those
3655 * functions will check that the new updates don't have the
3656 * same refname as any existing ones.)
3658 for (i
= 0; i
< transaction
->nr
; i
++) {
3659 struct ref_update
*update
= transaction
->updates
[i
];
3660 struct string_list_item
*item
=
3661 string_list_append(&affected_refnames
, update
->refname
);
3664 * We store a pointer to update in item->util, but at
3665 * the moment we never use the value of this field
3666 * except to check whether it is non-NULL.
3668 item
->util
= update
;
3670 string_list_sort(&affected_refnames
);
3671 if (ref_update_reject_duplicates(&affected_refnames
, err
)) {
3672 ret
= TRANSACTION_GENERIC_ERROR
;
3677 * Special hack: If a branch is updated directly and HEAD
3678 * points to it (may happen on the remote side of a push
3679 * for example) then logically the HEAD reflog should be
3682 * A generic solution would require reverse symref lookups,
3683 * but finding all symrefs pointing to a given branch would be
3684 * rather costly for this rare event (the direct update of a
3685 * branch) to be worth it. So let's cheat and check with HEAD
3686 * only, which should cover 99% of all usage scenarios (even
3687 * 100% of the default ones).
3689 * So if HEAD is a symbolic reference, then record the name of
3690 * the reference that it points to. If we see an update of
3691 * head_ref within the transaction, then split_head_update()
3692 * arranges for the reflog of HEAD to be updated, too.
3694 head_ref
= resolve_refdup("HEAD", RESOLVE_REF_NO_RECURSE
,
3695 head_oid
.hash
, &head_type
);
3697 if (head_ref
&& !(head_type
& REF_ISSYMREF
)) {
3703 * Acquire all locks, verify old values if provided, check
3704 * that new values are valid, and write new values to the
3705 * lockfiles, ready to be activated. Only keep one lockfile
3706 * open at a time to avoid running out of file descriptors.
3708 for (i
= 0; i
< transaction
->nr
; i
++) {
3709 struct ref_update
*update
= transaction
->updates
[i
];
3711 ret
= lock_ref_for_update(update
, transaction
, head_ref
,
3712 &affected_refnames
, err
);
3717 /* Perform updates first so live commits remain referenced */
3718 for (i
= 0; i
< transaction
->nr
; i
++) {
3719 struct ref_update
*update
= transaction
->updates
[i
];
3720 struct ref_lock
*lock
= update
->lock
;
3722 if (update
->flags
& REF_NEEDS_COMMIT
||
3723 update
->flags
& REF_LOG_ONLY
) {
3724 if (log_ref_write(lock
->ref_name
, lock
->old_oid
.hash
,
3726 update
->msg
, update
->flags
, err
)) {
3727 char *old_msg
= strbuf_detach(err
, NULL
);
3729 strbuf_addf(err
, "cannot update the ref '%s': %s",
3730 lock
->ref_name
, old_msg
);
3733 update
->lock
= NULL
;
3734 ret
= TRANSACTION_GENERIC_ERROR
;
3738 if (update
->flags
& REF_NEEDS_COMMIT
) {
3739 clear_loose_ref_cache(refs
);
3740 if (commit_ref(lock
)) {
3741 strbuf_addf(err
, "couldn't set '%s'", lock
->ref_name
);
3743 update
->lock
= NULL
;
3744 ret
= TRANSACTION_GENERIC_ERROR
;
3749 /* Perform deletes now that updates are safely completed */
3750 for (i
= 0; i
< transaction
->nr
; i
++) {
3751 struct ref_update
*update
= transaction
->updates
[i
];
3753 if (update
->flags
& REF_DELETING
&&
3754 !(update
->flags
& REF_LOG_ONLY
)) {
3755 if (delete_ref_loose(update
->lock
, update
->type
, err
)) {
3756 ret
= TRANSACTION_GENERIC_ERROR
;
3760 if (!(update
->flags
& REF_ISPRUNING
))
3761 string_list_append(&refs_to_delete
,
3762 update
->lock
->ref_name
);
3766 if (repack_without_refs(&refs_to_delete
, err
)) {
3767 ret
= TRANSACTION_GENERIC_ERROR
;
3770 for_each_string_list_item(ref_to_delete
, &refs_to_delete
)
3771 unlink_or_warn(git_path("logs/%s", ref_to_delete
->string
));
3772 clear_loose_ref_cache(refs
);
3775 transaction
->state
= REF_TRANSACTION_CLOSED
;
3777 for (i
= 0; i
< transaction
->nr
; i
++)
3778 if (transaction
->updates
[i
]->lock
)
3779 unlock_ref(transaction
->updates
[i
]->lock
);
3780 string_list_clear(&refs_to_delete
, 0);
3782 string_list_clear(&affected_refnames
, 0);
3787 static int ref_present(const char *refname
,
3788 const struct object_id
*oid
, int flags
, void *cb_data
)
3790 struct string_list
*affected_refnames
= cb_data
;
3792 return string_list_has_string(affected_refnames
, refname
);
3795 int initial_ref_transaction_commit(struct ref_transaction
*transaction
,
3798 struct files_ref_store
*refs
=
3799 get_files_ref_store(NULL
, "initial_ref_transaction_commit");
3801 struct string_list affected_refnames
= STRING_LIST_INIT_NODUP
;
3805 if (transaction
->state
!= REF_TRANSACTION_OPEN
)
3806 die("BUG: commit called for transaction that is not open");
3808 /* Fail if a refname appears more than once in the transaction: */
3809 for (i
= 0; i
< transaction
->nr
; i
++)
3810 string_list_append(&affected_refnames
,
3811 transaction
->updates
[i
]->refname
);
3812 string_list_sort(&affected_refnames
);
3813 if (ref_update_reject_duplicates(&affected_refnames
, err
)) {
3814 ret
= TRANSACTION_GENERIC_ERROR
;
3819 * It's really undefined to call this function in an active
3820 * repository or when there are existing references: we are
3821 * only locking and changing packed-refs, so (1) any
3822 * simultaneous processes might try to change a reference at
3823 * the same time we do, and (2) any existing loose versions of
3824 * the references that we are setting would have precedence
3825 * over our values. But some remote helpers create the remote
3826 * "HEAD" and "master" branches before calling this function,
3827 * so here we really only check that none of the references
3828 * that we are creating already exists.
3830 if (for_each_rawref(ref_present
, &affected_refnames
))
3831 die("BUG: initial ref transaction called with existing refs");
3833 for (i
= 0; i
< transaction
->nr
; i
++) {
3834 struct ref_update
*update
= transaction
->updates
[i
];
3836 if ((update
->flags
& REF_HAVE_OLD
) &&
3837 !is_null_sha1(update
->old_sha1
))
3838 die("BUG: initial ref transaction with old_sha1 set");
3839 if (verify_refname_available(update
->refname
,
3840 &affected_refnames
, NULL
,
3842 ret
= TRANSACTION_NAME_CONFLICT
;
3847 if (lock_packed_refs(refs
, 0)) {
3848 strbuf_addf(err
, "unable to lock packed-refs file: %s",
3850 ret
= TRANSACTION_GENERIC_ERROR
;
3854 for (i
= 0; i
< transaction
->nr
; i
++) {
3855 struct ref_update
*update
= transaction
->updates
[i
];
3857 if ((update
->flags
& REF_HAVE_NEW
) &&
3858 !is_null_sha1(update
->new_sha1
))
3859 add_packed_ref(refs
, update
->refname
, update
->new_sha1
);
3862 if (commit_packed_refs(refs
)) {
3863 strbuf_addf(err
, "unable to commit packed-refs file: %s",
3865 ret
= TRANSACTION_GENERIC_ERROR
;
3870 transaction
->state
= REF_TRANSACTION_CLOSED
;
3871 string_list_clear(&affected_refnames
, 0);
3875 struct expire_reflog_cb
{
3877 reflog_expiry_should_prune_fn
*should_prune_fn
;
3880 unsigned char last_kept_sha1
[20];
3883 static int expire_reflog_ent(unsigned char *osha1
, unsigned char *nsha1
,
3884 const char *email
, unsigned long timestamp
, int tz
,
3885 const char *message
, void *cb_data
)
3887 struct expire_reflog_cb
*cb
= cb_data
;
3888 struct expire_reflog_policy_cb
*policy_cb
= cb
->policy_cb
;
3890 if (cb
->flags
& EXPIRE_REFLOGS_REWRITE
)
3891 osha1
= cb
->last_kept_sha1
;
3893 if ((*cb
->should_prune_fn
)(osha1
, nsha1
, email
, timestamp
, tz
,
3894 message
, policy_cb
)) {
3896 printf("would prune %s", message
);
3897 else if (cb
->flags
& EXPIRE_REFLOGS_VERBOSE
)
3898 printf("prune %s", message
);
3901 fprintf(cb
->newlog
, "%s %s %s %lu %+05d\t%s",
3902 sha1_to_hex(osha1
), sha1_to_hex(nsha1
),
3903 email
, timestamp
, tz
, message
);
3904 hashcpy(cb
->last_kept_sha1
, nsha1
);
3906 if (cb
->flags
& EXPIRE_REFLOGS_VERBOSE
)
3907 printf("keep %s", message
);
3912 int reflog_expire(const char *refname
, const unsigned char *sha1
,
3914 reflog_expiry_prepare_fn prepare_fn
,
3915 reflog_expiry_should_prune_fn should_prune_fn
,
3916 reflog_expiry_cleanup_fn cleanup_fn
,
3917 void *policy_cb_data
)
3919 static struct lock_file reflog_lock
;
3920 struct expire_reflog_cb cb
;
3921 struct ref_lock
*lock
;
3925 struct strbuf err
= STRBUF_INIT
;
3927 memset(&cb
, 0, sizeof(cb
));
3929 cb
.policy_cb
= policy_cb_data
;
3930 cb
.should_prune_fn
= should_prune_fn
;
3933 * The reflog file is locked by holding the lock on the
3934 * reference itself, plus we might need to update the
3935 * reference if --updateref was specified:
3937 lock
= lock_ref_sha1_basic(refname
, sha1
, NULL
, NULL
, REF_NODEREF
,
3940 error("cannot lock ref '%s': %s", refname
, err
.buf
);
3941 strbuf_release(&err
);
3944 if (!reflog_exists(refname
)) {
3949 log_file
= git_pathdup("logs/%s", refname
);
3950 if (!(flags
& EXPIRE_REFLOGS_DRY_RUN
)) {
3952 * Even though holding $GIT_DIR/logs/$reflog.lock has
3953 * no locking implications, we use the lock_file
3954 * machinery here anyway because it does a lot of the
3955 * work we need, including cleaning up if the program
3956 * exits unexpectedly.
3958 if (hold_lock_file_for_update(&reflog_lock
, log_file
, 0) < 0) {
3959 struct strbuf err
= STRBUF_INIT
;
3960 unable_to_lock_message(log_file
, errno
, &err
);
3961 error("%s", err
.buf
);
3962 strbuf_release(&err
);
3965 cb
.newlog
= fdopen_lock_file(&reflog_lock
, "w");
3967 error("cannot fdopen %s (%s)",
3968 get_lock_file_path(&reflog_lock
), strerror(errno
));
3973 (*prepare_fn
)(refname
, sha1
, cb
.policy_cb
);
3974 for_each_reflog_ent(refname
, expire_reflog_ent
, &cb
);
3975 (*cleanup_fn
)(cb
.policy_cb
);
3977 if (!(flags
& EXPIRE_REFLOGS_DRY_RUN
)) {
3979 * It doesn't make sense to adjust a reference pointed
3980 * to by a symbolic ref based on expiring entries in
3981 * the symbolic reference's reflog. Nor can we update
3982 * a reference if there are no remaining reflog
3985 int update
= (flags
& EXPIRE_REFLOGS_UPDATE_REF
) &&
3986 !(type
& REF_ISSYMREF
) &&
3987 !is_null_sha1(cb
.last_kept_sha1
);
3989 if (close_lock_file(&reflog_lock
)) {
3990 status
|= error("couldn't write %s: %s", log_file
,
3992 } else if (update
&&
3993 (write_in_full(get_lock_file_fd(lock
->lk
),
3994 sha1_to_hex(cb
.last_kept_sha1
), 40) != 40 ||
3995 write_str_in_full(get_lock_file_fd(lock
->lk
), "\n") != 1 ||
3996 close_ref(lock
) < 0)) {
3997 status
|= error("couldn't write %s",
3998 get_lock_file_path(lock
->lk
));
3999 rollback_lock_file(&reflog_lock
);
4000 } else if (commit_lock_file(&reflog_lock
)) {
4001 status
|= error("unable to write reflog '%s' (%s)",
4002 log_file
, strerror(errno
));
4003 } else if (update
&& commit_ref(lock
)) {
4004 status
|= error("couldn't set %s", lock
->ref_name
);
4012 rollback_lock_file(&reflog_lock
);
4018 struct ref_storage_be refs_be_files
= {
4021 files_ref_store_create
,
4022 files_transaction_commit
,