6 #include "string-list.h"
9 * How to handle various characters in refnames:
10 * 0: An acceptable character for refs
12 * 2: ., look for a preceding . to reject .. in refs
13 * 3: {, look for a preceding @ to reject @{ in refs
14 * 4: A bad character: ASCII control characters, "~", "^", ":" or SP
16 static unsigned char refname_disposition[256] = {
17 1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
18 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
19 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 2, 1,
20 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4,
21 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
22 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 4, 0,
23 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
24 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 4
28 * Used as a flag to ref_transaction_delete when a loose ref is being
31 #define REF_ISPRUNING 0x0100
33 * Try to read one refname component from the front of refname.
34 * Return the length of the component found, or -1 if the component is
35 * not legal. It is legal if it is something reasonable to have under
36 * ".git/refs/"; We do not like it if:
38 * - any path component of it begins with ".", or
39 * - it has double dots "..", or
40 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
41 * - it ends with a "/".
42 * - it ends with ".lock"
43 * - it contains a "\" (backslash)
45 static int check_refname_component(const char *refname, int flags)
50 for (cp = refname; ; cp++) {
52 unsigned char disp = refname_disposition[ch];
58 return -1; /* Refname contains "..". */
62 return -1; /* Refname contains "@{". */
71 return 0; /* Component has zero length. */
72 if (refname[0] == '.') {
73 if (!(flags & REFNAME_DOT_COMPONENT))
74 return -1; /* Component starts with '.'. */
76 * Even if leading dots are allowed, don't allow "."
77 * as a component (".." is prevented by a rule above).
79 if (refname[1] == '\0')
80 return -1; /* Component equals ".". */
82 if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5))
83 return -1; /* Refname ends with ".lock". */
87 int check_refname_format(const char *refname, int flags)
89 int component_len, component_count = 0;
91 if (!strcmp(refname, "@"))
92 /* Refname is a single character '@'. */
96 /* We are at the start of a path component. */
97 component_len = check_refname_component(refname, flags);
98 if (component_len <= 0) {
99 if ((flags & REFNAME_REFSPEC_PATTERN) &&
101 (refname[1] == '\0' || refname[1] == '/')) {
102 /* Accept one wildcard as a full refname component. */
103 flags &= ~REFNAME_REFSPEC_PATTERN;
110 if (refname[component_len] == '\0')
112 /* Skip to next component. */
113 refname += component_len + 1;
116 if (refname[component_len - 1] == '.')
117 return -1; /* Refname ends with '.'. */
118 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
119 return -1; /* Refname has only one component. */
126 * Information used (along with the information in ref_entry) to
127 * describe a single cached reference. This data structure only
128 * occurs embedded in a union in struct ref_entry, and only when
129 * (ref_entry->flag & REF_DIR) is zero.
133 * The name of the object to which this reference resolves
134 * (which may be a tag object). If REF_ISBROKEN, this is
135 * null. If REF_ISSYMREF, then this is the name of the object
136 * referred to by the last reference in the symlink chain.
138 unsigned char sha1[20];
141 * If REF_KNOWS_PEELED, then this field holds the peeled value
142 * of this reference, or null if the reference is known not to
143 * be peelable. See the documentation for peel_ref() for an
144 * exact definition of "peelable".
146 unsigned char peeled[20];
152 * Information used (along with the information in ref_entry) to
153 * describe a level in the hierarchy of references. This data
154 * structure only occurs embedded in a union in struct ref_entry, and
155 * only when (ref_entry.flag & REF_DIR) is set. In that case,
156 * (ref_entry.flag & REF_INCOMPLETE) determines whether the references
157 * in the directory have already been read:
159 * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose
160 * or packed references, already read.
162 * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose
163 * references that hasn't been read yet (nor has any of its
166 * Entries within a directory are stored within a growable array of
167 * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i <
168 * sorted are sorted by their component name in strcmp() order and the
169 * remaining entries are unsorted.
171 * Loose references are read lazily, one directory at a time. When a
172 * directory of loose references is read, then all of the references
173 * in that directory are stored, and REF_INCOMPLETE stubs are created
174 * for any subdirectories, but the subdirectories themselves are not
175 * read. The reading is triggered by get_ref_dir().
181 * Entries with index 0 <= i < sorted are sorted by name. New
182 * entries are appended to the list unsorted, and are sorted
183 * only when required; thus we avoid the need to sort the list
184 * after the addition of every reference.
188 /* A pointer to the ref_cache that contains this ref_dir. */
189 struct ref_cache *ref_cache;
191 struct ref_entry **entries;
195 * Bit values for ref_entry::flag. REF_ISSYMREF=0x01,
196 * REF_ISPACKED=0x02, and REF_ISBROKEN=0x04 are public values; see
201 * The field ref_entry->u.value.peeled of this value entry contains
202 * the correct peeled value for the reference, which might be
203 * null_sha1 if the reference is not a tag or if it is broken.
205 #define REF_KNOWS_PEELED 0x08
207 /* ref_entry represents a directory of references */
211 * Entry has not yet been read from disk (used only for REF_DIR
212 * entries representing loose references)
214 #define REF_INCOMPLETE 0x20
217 * A ref_entry represents either a reference or a "subdirectory" of
220 * Each directory in the reference namespace is represented by a
221 * ref_entry with (flags & REF_DIR) set and containing a subdir member
222 * that holds the entries in that directory that have been read so
223 * far. If (flags & REF_INCOMPLETE) is set, then the directory and
224 * its subdirectories haven't been read yet. REF_INCOMPLETE is only
225 * used for loose reference directories.
227 * References are represented by a ref_entry with (flags & REF_DIR)
228 * unset and a value member that describes the reference's value. The
229 * flag member is at the ref_entry level, but it is also needed to
230 * interpret the contents of the value field (in other words, a
231 * ref_value object is not very much use without the enclosing
234 * Reference names cannot end with slash and directories' names are
235 * always stored with a trailing slash (except for the top-level
236 * directory, which is always denoted by ""). This has two nice
237 * consequences: (1) when the entries in each subdir are sorted
238 * lexicographically by name (as they usually are), the references in
239 * a whole tree can be generated in lexicographic order by traversing
240 * the tree in left-to-right, depth-first order; (2) the names of
241 * references and subdirectories cannot conflict, and therefore the
242 * presence of an empty subdirectory does not block the creation of a
243 * similarly-named reference. (The fact that reference names with the
244 * same leading components can conflict *with each other* is a
245 * separate issue that is regulated by is_refname_available().)
247 * Please note that the name field contains the fully-qualified
248 * reference (or subdirectory) name. Space could be saved by only
249 * storing the relative names. But that would require the full names
250 * to be generated on the fly when iterating in do_for_each_ref(), and
251 * would break callback functions, who have always been able to assume
252 * that the name strings that they are passed will not be freed during
256 unsigned char flag; /* ISSYMREF? ISPACKED? */
258 struct ref_value value; /* if not (flags&REF_DIR) */
259 struct ref_dir subdir; /* if (flags&REF_DIR) */
262 * The full name of the reference (e.g., "refs/heads/master")
263 * or the full name of the directory with a trailing slash
264 * (e.g., "refs/heads/"):
266 char name[FLEX_ARRAY];
269 static void read_loose_refs(const char *dirname, struct ref_dir *dir);
271 static struct ref_dir *get_ref_dir(struct ref_entry *entry)
274 assert(entry->flag & REF_DIR);
275 dir = &entry->u.subdir;
276 if (entry->flag & REF_INCOMPLETE) {
277 read_loose_refs(entry->name, dir);
278 entry->flag &= ~REF_INCOMPLETE;
283 static struct ref_entry *create_ref_entry(const char *refname,
284 const unsigned char *sha1, int flag,
288 struct ref_entry *ref;
291 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
292 die("Reference has invalid format: '%s'", refname);
293 len = strlen(refname) + 1;
294 ref = xmalloc(sizeof(struct ref_entry) + len);
295 hashcpy(ref->u.value.sha1, sha1);
296 hashclr(ref->u.value.peeled);
297 memcpy(ref->name, refname, len);
302 static void clear_ref_dir(struct ref_dir *dir);
304 static void free_ref_entry(struct ref_entry *entry)
306 if (entry->flag & REF_DIR) {
308 * Do not use get_ref_dir() here, as that might
309 * trigger the reading of loose refs.
311 clear_ref_dir(&entry->u.subdir);
317 * Add a ref_entry to the end of dir (unsorted). Entry is always
318 * stored directly in dir; no recursion into subdirectories is
321 static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry)
323 ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc);
324 dir->entries[dir->nr++] = entry;
325 /* optimize for the case that entries are added in order */
327 (dir->nr == dir->sorted + 1 &&
328 strcmp(dir->entries[dir->nr - 2]->name,
329 dir->entries[dir->nr - 1]->name) < 0))
330 dir->sorted = dir->nr;
334 * Clear and free all entries in dir, recursively.
336 static void clear_ref_dir(struct ref_dir *dir)
339 for (i = 0; i < dir->nr; i++)
340 free_ref_entry(dir->entries[i]);
342 dir->sorted = dir->nr = dir->alloc = 0;
347 * Create a struct ref_entry object for the specified dirname.
348 * dirname is the name of the directory with a trailing slash (e.g.,
349 * "refs/heads/") or "" for the top-level directory.
351 static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache,
352 const char *dirname, size_t len,
355 struct ref_entry *direntry;
356 direntry = xcalloc(1, sizeof(struct ref_entry) + len + 1);
357 memcpy(direntry->name, dirname, len);
358 direntry->name[len] = '\0';
359 direntry->u.subdir.ref_cache = ref_cache;
360 direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE : 0);
364 static int ref_entry_cmp(const void *a, const void *b)
366 struct ref_entry *one = *(struct ref_entry **)a;
367 struct ref_entry *two = *(struct ref_entry **)b;
368 return strcmp(one->name, two->name);
371 static void sort_ref_dir(struct ref_dir *dir);
373 struct string_slice {
378 static int ref_entry_cmp_sslice(const void *key_, const void *ent_)
380 const struct string_slice *key = key_;
381 const struct ref_entry *ent = *(const struct ref_entry * const *)ent_;
382 int cmp = strncmp(key->str, ent->name, key->len);
385 return '\0' - (unsigned char)ent->name[key->len];
389 * Return the index of the entry with the given refname from the
390 * ref_dir (non-recursively), sorting dir if necessary. Return -1 if
391 * no such entry is found. dir must already be complete.
393 static int search_ref_dir(struct ref_dir *dir, const char *refname, size_t len)
395 struct ref_entry **r;
396 struct string_slice key;
398 if (refname == NULL || !dir->nr)
404 r = bsearch(&key, dir->entries, dir->nr, sizeof(*dir->entries),
405 ref_entry_cmp_sslice);
410 return r - dir->entries;
414 * Search for a directory entry directly within dir (without
415 * recursing). Sort dir if necessary. subdirname must be a directory
416 * name (i.e., end in '/'). If mkdir is set, then create the
417 * directory if it is missing; otherwise, return NULL if the desired
418 * directory cannot be found. dir must already be complete.
420 static struct ref_dir *search_for_subdir(struct ref_dir *dir,
421 const char *subdirname, size_t len,
424 int entry_index = search_ref_dir(dir, subdirname, len);
425 struct ref_entry *entry;
426 if (entry_index == -1) {
430 * Since dir is complete, the absence of a subdir
431 * means that the subdir really doesn't exist;
432 * therefore, create an empty record for it but mark
433 * the record complete.
435 entry = create_dir_entry(dir->ref_cache, subdirname, len, 0);
436 add_entry_to_dir(dir, entry);
438 entry = dir->entries[entry_index];
440 return get_ref_dir(entry);
444 * If refname is a reference name, find the ref_dir within the dir
445 * tree that should hold refname. If refname is a directory name
446 * (i.e., ends in '/'), then return that ref_dir itself. dir must
447 * represent the top-level directory and must already be complete.
448 * Sort ref_dirs and recurse into subdirectories as necessary. If
449 * mkdir is set, then create any missing directories; otherwise,
450 * return NULL if the desired directory cannot be found.
452 static struct ref_dir *find_containing_dir(struct ref_dir *dir,
453 const char *refname, int mkdir)
456 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
457 size_t dirnamelen = slash - refname + 1;
458 struct ref_dir *subdir;
459 subdir = search_for_subdir(dir, refname, dirnamelen, mkdir);
471 * Find the value entry with the given name in dir, sorting ref_dirs
472 * and recursing into subdirectories as necessary. If the name is not
473 * found or it corresponds to a directory entry, return NULL.
475 static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname)
478 struct ref_entry *entry;
479 dir = find_containing_dir(dir, refname, 0);
482 entry_index = search_ref_dir(dir, refname, strlen(refname));
483 if (entry_index == -1)
485 entry = dir->entries[entry_index];
486 return (entry->flag & REF_DIR) ? NULL : entry;
490 * Remove the entry with the given name from dir, recursing into
491 * subdirectories as necessary. If refname is the name of a directory
492 * (i.e., ends with '/'), then remove the directory and its contents.
493 * If the removal was successful, return the number of entries
494 * remaining in the directory entry that contained the deleted entry.
495 * If the name was not found, return -1. Please note that this
496 * function only deletes the entry from the cache; it does not delete
497 * it from the filesystem or ensure that other cache entries (which
498 * might be symbolic references to the removed entry) are updated.
499 * Nor does it remove any containing dir entries that might be made
500 * empty by the removal. dir must represent the top-level directory
501 * and must already be complete.
503 static int remove_entry(struct ref_dir *dir, const char *refname)
505 int refname_len = strlen(refname);
507 struct ref_entry *entry;
508 int is_dir = refname[refname_len - 1] == '/';
511 * refname represents a reference directory. Remove
512 * the trailing slash; otherwise we will get the
513 * directory *representing* refname rather than the
514 * one *containing* it.
516 char *dirname = xmemdupz(refname, refname_len - 1);
517 dir = find_containing_dir(dir, dirname, 0);
520 dir = find_containing_dir(dir, refname, 0);
524 entry_index = search_ref_dir(dir, refname, refname_len);
525 if (entry_index == -1)
527 entry = dir->entries[entry_index];
529 memmove(&dir->entries[entry_index],
530 &dir->entries[entry_index + 1],
531 (dir->nr - entry_index - 1) * sizeof(*dir->entries)
534 if (dir->sorted > entry_index)
536 free_ref_entry(entry);
541 * Add a ref_entry to the ref_dir (unsorted), recursing into
542 * subdirectories as necessary. dir must represent the top-level
543 * directory. Return 0 on success.
545 static int add_ref(struct ref_dir *dir, struct ref_entry *ref)
547 dir = find_containing_dir(dir, ref->name, 1);
550 add_entry_to_dir(dir, ref);
555 * Emit a warning and return true iff ref1 and ref2 have the same name
556 * and the same sha1. Die if they have the same name but different
559 static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
561 if (strcmp(ref1->name, ref2->name))
564 /* Duplicate name; make sure that they don't conflict: */
566 if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR))
567 /* This is impossible by construction */
568 die("Reference directory conflict: %s", ref1->name);
570 if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1))
571 die("Duplicated ref, and SHA1s don't match: %s", ref1->name);
573 warning("Duplicated ref: %s", ref1->name);
578 * Sort the entries in dir non-recursively (if they are not already
579 * sorted) and remove any duplicate entries.
581 static void sort_ref_dir(struct ref_dir *dir)
584 struct ref_entry *last = NULL;
587 * This check also prevents passing a zero-length array to qsort(),
588 * which is a problem on some platforms.
590 if (dir->sorted == dir->nr)
593 qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp);
595 /* Remove any duplicates: */
596 for (i = 0, j = 0; j < dir->nr; j++) {
597 struct ref_entry *entry = dir->entries[j];
598 if (last && is_dup_ref(last, entry))
599 free_ref_entry(entry);
601 last = dir->entries[i++] = entry;
603 dir->sorted = dir->nr = i;
606 /* Include broken references in a do_for_each_ref*() iteration: */
607 #define DO_FOR_EACH_INCLUDE_BROKEN 0x01
610 * Return true iff the reference described by entry can be resolved to
611 * an object in the database. Emit a warning if the referred-to
612 * object does not exist.
614 static int ref_resolves_to_object(struct ref_entry *entry)
616 if (entry->flag & REF_ISBROKEN)
618 if (!has_sha1_file(entry->u.value.sha1)) {
619 error("%s does not point to a valid object!", entry->name);
626 * current_ref is a performance hack: when iterating over references
627 * using the for_each_ref*() functions, current_ref is set to the
628 * current reference's entry before calling the callback function. If
629 * the callback function calls peel_ref(), then peel_ref() first
630 * checks whether the reference to be peeled is the current reference
631 * (it usually is) and if so, returns that reference's peeled version
632 * if it is available. This avoids a refname lookup in a common case.
634 static struct ref_entry *current_ref;
636 typedef int each_ref_entry_fn(struct ref_entry *entry, void *cb_data);
638 struct ref_entry_cb {
647 * Handle one reference in a do_for_each_ref*()-style iteration,
648 * calling an each_ref_fn for each entry.
650 static int do_one_ref(struct ref_entry *entry, void *cb_data)
652 struct ref_entry_cb *data = cb_data;
653 struct ref_entry *old_current_ref;
656 if (!starts_with(entry->name, data->base))
659 if (!(data->flags & DO_FOR_EACH_INCLUDE_BROKEN) &&
660 !ref_resolves_to_object(entry))
663 /* Store the old value, in case this is a recursive call: */
664 old_current_ref = current_ref;
666 retval = data->fn(entry->name + data->trim, entry->u.value.sha1,
667 entry->flag, data->cb_data);
668 current_ref = old_current_ref;
673 * Call fn for each reference in dir that has index in the range
674 * offset <= index < dir->nr. Recurse into subdirectories that are in
675 * that index range, sorting them before iterating. This function
676 * does not sort dir itself; it should be sorted beforehand. fn is
677 * called for all references, including broken ones.
679 static int do_for_each_entry_in_dir(struct ref_dir *dir, int offset,
680 each_ref_entry_fn fn, void *cb_data)
683 assert(dir->sorted == dir->nr);
684 for (i = offset; i < dir->nr; i++) {
685 struct ref_entry *entry = dir->entries[i];
687 if (entry->flag & REF_DIR) {
688 struct ref_dir *subdir = get_ref_dir(entry);
689 sort_ref_dir(subdir);
690 retval = do_for_each_entry_in_dir(subdir, 0, fn, cb_data);
692 retval = fn(entry, cb_data);
701 * Call fn for each reference in the union of dir1 and dir2, in order
702 * by refname. Recurse into subdirectories. If a value entry appears
703 * in both dir1 and dir2, then only process the version that is in
704 * dir2. The input dirs must already be sorted, but subdirs will be
705 * sorted as needed. fn is called for all references, including
708 static int do_for_each_entry_in_dirs(struct ref_dir *dir1,
709 struct ref_dir *dir2,
710 each_ref_entry_fn fn, void *cb_data)
715 assert(dir1->sorted == dir1->nr);
716 assert(dir2->sorted == dir2->nr);
718 struct ref_entry *e1, *e2;
720 if (i1 == dir1->nr) {
721 return do_for_each_entry_in_dir(dir2, i2, fn, cb_data);
723 if (i2 == dir2->nr) {
724 return do_for_each_entry_in_dir(dir1, i1, fn, cb_data);
726 e1 = dir1->entries[i1];
727 e2 = dir2->entries[i2];
728 cmp = strcmp(e1->name, e2->name);
730 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) {
731 /* Both are directories; descend them in parallel. */
732 struct ref_dir *subdir1 = get_ref_dir(e1);
733 struct ref_dir *subdir2 = get_ref_dir(e2);
734 sort_ref_dir(subdir1);
735 sort_ref_dir(subdir2);
736 retval = do_for_each_entry_in_dirs(
737 subdir1, subdir2, fn, cb_data);
740 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) {
741 /* Both are references; ignore the one from dir1. */
742 retval = fn(e2, cb_data);
746 die("conflict between reference and directory: %s",
758 if (e->flag & REF_DIR) {
759 struct ref_dir *subdir = get_ref_dir(e);
760 sort_ref_dir(subdir);
761 retval = do_for_each_entry_in_dir(
762 subdir, 0, fn, cb_data);
764 retval = fn(e, cb_data);
773 * Load all of the refs from the dir into our in-memory cache. The hard work
774 * of loading loose refs is done by get_ref_dir(), so we just need to recurse
775 * through all of the sub-directories. We do not even need to care about
776 * sorting, as traversal order does not matter to us.
778 static void prime_ref_dir(struct ref_dir *dir)
781 for (i = 0; i < dir->nr; i++) {
782 struct ref_entry *entry = dir->entries[i];
783 if (entry->flag & REF_DIR)
784 prime_ref_dir(get_ref_dir(entry));
788 static int entry_matches(struct ref_entry *entry, const char *refname)
790 return refname && !strcmp(entry->name, refname);
793 struct nonmatching_ref_data {
795 struct ref_entry *found;
798 static int nonmatching_ref_fn(struct ref_entry *entry, void *vdata)
800 struct nonmatching_ref_data *data = vdata;
802 if (entry_matches(entry, data->skip))
809 static void report_refname_conflict(struct ref_entry *entry,
812 error("'%s' exists; cannot create '%s'", entry->name, refname);
816 * Return true iff a reference named refname could be created without
817 * conflicting with the name of an existing reference in dir. If
818 * oldrefname is non-NULL, ignore potential conflicts with oldrefname
819 * (e.g., because oldrefname is scheduled for deletion in the same
822 * Two reference names conflict if one of them exactly matches the
823 * leading components of the other; e.g., "foo/bar" conflicts with
824 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
827 static int is_refname_available(const char *refname, const char *oldrefname,
835 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
837 * We are still at a leading dir of the refname; we are
838 * looking for a conflict with a leaf entry.
840 * If we find one, we still must make sure it is
843 pos = search_ref_dir(dir, refname, slash - refname);
845 struct ref_entry *entry = dir->entries[pos];
846 if (entry_matches(entry, oldrefname))
848 report_refname_conflict(entry, refname);
854 * Otherwise, we can try to continue our search with
855 * the next component; if we come up empty, we know
856 * there is nothing under this whole prefix.
858 pos = search_ref_dir(dir, refname, slash + 1 - refname);
862 dir = get_ref_dir(dir->entries[pos]);
866 * We are at the leaf of our refname; we want to
867 * make sure there are no directories which match it.
869 len = strlen(refname);
870 dirname = xmallocz(len + 1);
871 sprintf(dirname, "%s/", refname);
872 pos = search_ref_dir(dir, dirname, len + 1);
877 * We found a directory named "refname". It is a
878 * problem iff it contains any ref that is not
881 struct ref_entry *entry = dir->entries[pos];
882 struct ref_dir *dir = get_ref_dir(entry);
883 struct nonmatching_ref_data data;
885 data.skip = oldrefname;
887 if (!do_for_each_entry_in_dir(dir, 0, nonmatching_ref_fn, &data))
890 report_refname_conflict(data.found, refname);
895 * There is no point in searching for another leaf
896 * node which matches it; such an entry would be the
897 * ref we are looking for, not a conflict.
902 struct packed_ref_cache {
903 struct ref_entry *root;
906 * Count of references to the data structure in this instance,
907 * including the pointer from ref_cache::packed if any. The
908 * data will not be freed as long as the reference count is
911 unsigned int referrers;
914 * Iff the packed-refs file associated with this instance is
915 * currently locked for writing, this points at the associated
916 * lock (which is owned by somebody else). The referrer count
917 * is also incremented when the file is locked and decremented
918 * when it is unlocked.
920 struct lock_file *lock;
922 /* The metadata from when this packed-refs cache was read */
923 struct stat_validity validity;
927 * Future: need to be in "struct repository"
928 * when doing a full libification.
930 static struct ref_cache {
931 struct ref_cache *next;
932 struct ref_entry *loose;
933 struct packed_ref_cache *packed;
935 * The submodule name, or "" for the main repo. We allocate
936 * length 1 rather than FLEX_ARRAY so that the main ref_cache
937 * is initialized correctly.
940 } ref_cache, *submodule_ref_caches;
942 /* Lock used for the main packed-refs file: */
943 static struct lock_file packlock;
946 * Increment the reference count of *packed_refs.
948 static void acquire_packed_ref_cache(struct packed_ref_cache *packed_refs)
950 packed_refs->referrers++;
954 * Decrease the reference count of *packed_refs. If it goes to zero,
955 * free *packed_refs and return true; otherwise return false.
957 static int release_packed_ref_cache(struct packed_ref_cache *packed_refs)
959 if (!--packed_refs->referrers) {
960 free_ref_entry(packed_refs->root);
961 stat_validity_clear(&packed_refs->validity);
969 static void clear_packed_ref_cache(struct ref_cache *refs)
972 struct packed_ref_cache *packed_refs = refs->packed;
974 if (packed_refs->lock)
975 die("internal error: packed-ref cache cleared while locked");
977 release_packed_ref_cache(packed_refs);
981 static void clear_loose_ref_cache(struct ref_cache *refs)
984 free_ref_entry(refs->loose);
989 static struct ref_cache *create_ref_cache(const char *submodule)
992 struct ref_cache *refs;
995 len = strlen(submodule) + 1;
996 refs = xcalloc(1, sizeof(struct ref_cache) + len);
997 memcpy(refs->name, submodule, len);
1002 * Return a pointer to a ref_cache for the specified submodule. For
1003 * the main repository, use submodule==NULL. The returned structure
1004 * will be allocated and initialized but not necessarily populated; it
1005 * should not be freed.
1007 static struct ref_cache *get_ref_cache(const char *submodule)
1009 struct ref_cache *refs;
1011 if (!submodule || !*submodule)
1014 for (refs = submodule_ref_caches; refs; refs = refs->next)
1015 if (!strcmp(submodule, refs->name))
1018 refs = create_ref_cache(submodule);
1019 refs->next = submodule_ref_caches;
1020 submodule_ref_caches = refs;
1024 /* The length of a peeled reference line in packed-refs, including EOL: */
1025 #define PEELED_LINE_LENGTH 42
1028 * The packed-refs header line that we write out. Perhaps other
1029 * traits will be added later. The trailing space is required.
1031 static const char PACKED_REFS_HEADER[] =
1032 "# pack-refs with: peeled fully-peeled \n";
1035 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
1036 * Return a pointer to the refname within the line (null-terminated),
1037 * or NULL if there was a problem.
1039 static const char *parse_ref_line(char *line, unsigned char *sha1)
1042 * 42: the answer to everything.
1044 * In this case, it happens to be the answer to
1045 * 40 (length of sha1 hex representation)
1046 * +1 (space in between hex and name)
1047 * +1 (newline at the end of the line)
1049 int len = strlen(line) - 42;
1053 if (get_sha1_hex(line, sha1) < 0)
1055 if (!isspace(line[40]))
1060 if (line[len] != '\n')
1068 * Read f, which is a packed-refs file, into dir.
1070 * A comment line of the form "# pack-refs with: " may contain zero or
1071 * more traits. We interpret the traits as follows:
1075 * Probably no references are peeled. But if the file contains a
1076 * peeled value for a reference, we will use it.
1080 * References under "refs/tags/", if they *can* be peeled, *are*
1081 * peeled in this file. References outside of "refs/tags/" are
1082 * probably not peeled even if they could have been, but if we find
1083 * a peeled value for such a reference we will use it.
1087 * All references in the file that can be peeled are peeled.
1088 * Inversely (and this is more important), any references in the
1089 * file for which no peeled value is recorded is not peelable. This
1090 * trait should typically be written alongside "peeled" for
1091 * compatibility with older clients, but we do not require it
1092 * (i.e., "peeled" is a no-op if "fully-peeled" is set).
1094 static void read_packed_refs(FILE *f, struct ref_dir *dir)
1096 struct ref_entry *last = NULL;
1097 char refline[PATH_MAX];
1098 enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE;
1100 while (fgets(refline, sizeof(refline), f)) {
1101 unsigned char sha1[20];
1102 const char *refname;
1103 static const char header[] = "# pack-refs with:";
1105 if (!strncmp(refline, header, sizeof(header)-1)) {
1106 const char *traits = refline + sizeof(header) - 1;
1107 if (strstr(traits, " fully-peeled "))
1108 peeled = PEELED_FULLY;
1109 else if (strstr(traits, " peeled "))
1110 peeled = PEELED_TAGS;
1111 /* perhaps other traits later as well */
1115 refname = parse_ref_line(refline, sha1);
1117 last = create_ref_entry(refname, sha1, REF_ISPACKED, 1);
1118 if (peeled == PEELED_FULLY ||
1119 (peeled == PEELED_TAGS && starts_with(refname, "refs/tags/")))
1120 last->flag |= REF_KNOWS_PEELED;
1125 refline[0] == '^' &&
1126 strlen(refline) == PEELED_LINE_LENGTH &&
1127 refline[PEELED_LINE_LENGTH - 1] == '\n' &&
1128 !get_sha1_hex(refline + 1, sha1)) {
1129 hashcpy(last->u.value.peeled, sha1);
1131 * Regardless of what the file header said,
1132 * we definitely know the value of *this*
1135 last->flag |= REF_KNOWS_PEELED;
1141 * Get the packed_ref_cache for the specified ref_cache, creating it
1144 static struct packed_ref_cache *get_packed_ref_cache(struct ref_cache *refs)
1146 const char *packed_refs_file;
1149 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
1151 packed_refs_file = git_path("packed-refs");
1154 !stat_validity_check(&refs->packed->validity, packed_refs_file))
1155 clear_packed_ref_cache(refs);
1157 if (!refs->packed) {
1160 refs->packed = xcalloc(1, sizeof(*refs->packed));
1161 acquire_packed_ref_cache(refs->packed);
1162 refs->packed->root = create_dir_entry(refs, "", 0, 0);
1163 f = fopen(packed_refs_file, "r");
1165 stat_validity_update(&refs->packed->validity, fileno(f));
1166 read_packed_refs(f, get_ref_dir(refs->packed->root));
1170 return refs->packed;
1173 static struct ref_dir *get_packed_ref_dir(struct packed_ref_cache *packed_ref_cache)
1175 return get_ref_dir(packed_ref_cache->root);
1178 static struct ref_dir *get_packed_refs(struct ref_cache *refs)
1180 return get_packed_ref_dir(get_packed_ref_cache(refs));
1183 void add_packed_ref(const char *refname, const unsigned char *sha1)
1185 struct packed_ref_cache *packed_ref_cache =
1186 get_packed_ref_cache(&ref_cache);
1188 if (!packed_ref_cache->lock)
1189 die("internal error: packed refs not locked");
1190 add_ref(get_packed_ref_dir(packed_ref_cache),
1191 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
1195 * Read the loose references from the namespace dirname into dir
1196 * (without recursing). dirname must end with '/'. dir must be the
1197 * directory entry corresponding to dirname.
1199 static void read_loose_refs(const char *dirname, struct ref_dir *dir)
1201 struct ref_cache *refs = dir->ref_cache;
1205 int dirnamelen = strlen(dirname);
1206 struct strbuf refname;
1209 path = git_path_submodule(refs->name, "%s", dirname);
1211 path = git_path("%s", dirname);
1217 strbuf_init(&refname, dirnamelen + 257);
1218 strbuf_add(&refname, dirname, dirnamelen);
1220 while ((de = readdir(d)) != NULL) {
1221 unsigned char sha1[20];
1226 if (de->d_name[0] == '.')
1228 if (ends_with(de->d_name, ".lock"))
1230 strbuf_addstr(&refname, de->d_name);
1231 refdir = *refs->name
1232 ? git_path_submodule(refs->name, "%s", refname.buf)
1233 : git_path("%s", refname.buf);
1234 if (stat(refdir, &st) < 0) {
1235 ; /* silently ignore */
1236 } else if (S_ISDIR(st.st_mode)) {
1237 strbuf_addch(&refname, '/');
1238 add_entry_to_dir(dir,
1239 create_dir_entry(refs, refname.buf,
1245 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {
1247 flag |= REF_ISBROKEN;
1249 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {
1251 flag |= REF_ISBROKEN;
1253 add_entry_to_dir(dir,
1254 create_ref_entry(refname.buf, sha1, flag, 1));
1256 strbuf_setlen(&refname, dirnamelen);
1258 strbuf_release(&refname);
1262 static struct ref_dir *get_loose_refs(struct ref_cache *refs)
1266 * Mark the top-level directory complete because we
1267 * are about to read the only subdirectory that can
1270 refs->loose = create_dir_entry(refs, "", 0, 0);
1272 * Create an incomplete entry for "refs/":
1274 add_entry_to_dir(get_ref_dir(refs->loose),
1275 create_dir_entry(refs, "refs/", 5, 1));
1277 return get_ref_dir(refs->loose);
1280 /* We allow "recursive" symbolic refs. Only within reason, though */
1282 #define MAXREFLEN (1024)
1285 * Called by resolve_gitlink_ref_recursive() after it failed to read
1286 * from the loose refs in ref_cache refs. Find <refname> in the
1287 * packed-refs file for the submodule.
1289 static int resolve_gitlink_packed_ref(struct ref_cache *refs,
1290 const char *refname, unsigned char *sha1)
1292 struct ref_entry *ref;
1293 struct ref_dir *dir = get_packed_refs(refs);
1295 ref = find_ref(dir, refname);
1299 hashcpy(sha1, ref->u.value.sha1);
1303 static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
1304 const char *refname, unsigned char *sha1,
1308 char buffer[128], *p;
1311 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
1314 ? git_path_submodule(refs->name, "%s", refname)
1315 : git_path("%s", refname);
1316 fd = open(path, O_RDONLY);
1318 return resolve_gitlink_packed_ref(refs, refname, sha1);
1320 len = read(fd, buffer, sizeof(buffer)-1);
1324 while (len && isspace(buffer[len-1]))
1328 /* Was it a detached head or an old-fashioned symlink? */
1329 if (!get_sha1_hex(buffer, sha1))
1333 if (strncmp(buffer, "ref:", 4))
1339 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
1342 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
1344 int len = strlen(path), retval;
1346 struct ref_cache *refs;
1348 while (len && path[len-1] == '/')
1352 submodule = xstrndup(path, len);
1353 refs = get_ref_cache(submodule);
1356 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
1361 * Return the ref_entry for the given refname from the packed
1362 * references. If it does not exist, return NULL.
1364 static struct ref_entry *get_packed_ref(const char *refname)
1366 return find_ref(get_packed_refs(&ref_cache), refname);
1370 * A loose ref file doesn't exist; check for a packed ref. The
1371 * options are forwarded from resolve_safe_unsafe().
1373 static const char *handle_missing_loose_ref(const char *refname,
1374 unsigned char *sha1,
1378 struct ref_entry *entry;
1381 * The loose reference file does not exist; check for a packed
1384 entry = get_packed_ref(refname);
1386 hashcpy(sha1, entry->u.value.sha1);
1388 *flag |= REF_ISPACKED;
1391 /* The reference is not a packed reference, either. */
1400 /* This function needs to return a meaningful errno on failure */
1401 const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
1403 int depth = MAXDEPTH;
1406 static char refname_buffer[256];
1411 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1417 char path[PATH_MAX];
1427 git_snpath(path, sizeof(path), "%s", refname);
1430 * We might have to loop back here to avoid a race
1431 * condition: first we lstat() the file, then we try
1432 * to read it as a link or as a file. But if somebody
1433 * changes the type of the file (file <-> directory
1434 * <-> symlink) between the lstat() and reading, then
1435 * we don't want to report that as an error but rather
1436 * try again starting with the lstat().
1439 if (lstat(path, &st) < 0) {
1440 if (errno == ENOENT)
1441 return handle_missing_loose_ref(refname, sha1,
1447 /* Follow "normalized" - ie "refs/.." symlinks by hand */
1448 if (S_ISLNK(st.st_mode)) {
1449 len = readlink(path, buffer, sizeof(buffer)-1);
1451 if (errno == ENOENT || errno == EINVAL)
1452 /* inconsistent with lstat; retry */
1458 if (starts_with(buffer, "refs/") &&
1459 !check_refname_format(buffer, 0)) {
1460 strcpy(refname_buffer, buffer);
1461 refname = refname_buffer;
1463 *flag |= REF_ISSYMREF;
1468 /* Is it a directory? */
1469 if (S_ISDIR(st.st_mode)) {
1475 * Anything else, just open it and try to use it as
1478 fd = open(path, O_RDONLY);
1480 if (errno == ENOENT)
1481 /* inconsistent with lstat; retry */
1486 len = read_in_full(fd, buffer, sizeof(buffer)-1);
1488 int save_errno = errno;
1494 while (len && isspace(buffer[len-1]))
1499 * Is it a symbolic ref?
1501 if (!starts_with(buffer, "ref:")) {
1503 * Please note that FETCH_HEAD has a second
1504 * line containing other data.
1506 if (get_sha1_hex(buffer, sha1) ||
1507 (buffer[40] != '\0' && !isspace(buffer[40]))) {
1509 *flag |= REF_ISBROKEN;
1516 *flag |= REF_ISSYMREF;
1518 while (isspace(*buf))
1520 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
1522 *flag |= REF_ISBROKEN;
1526 refname = strcpy(refname_buffer, buf);
1530 char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
1532 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
1533 return ret ? xstrdup(ret) : NULL;
1536 /* The argument to filter_refs */
1538 const char *pattern;
1543 int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
1545 if (resolve_ref_unsafe(refname, sha1, reading, flags))
1550 int read_ref(const char *refname, unsigned char *sha1)
1552 return read_ref_full(refname, sha1, 1, NULL);
1555 int ref_exists(const char *refname)
1557 unsigned char sha1[20];
1558 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
1561 static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
1564 struct ref_filter *filter = (struct ref_filter *)data;
1565 if (wildmatch(filter->pattern, refname, 0, NULL))
1567 return filter->fn(refname, sha1, flags, filter->cb_data);
1571 /* object was peeled successfully: */
1575 * object cannot be peeled because the named object (or an
1576 * object referred to by a tag in the peel chain), does not
1581 /* object cannot be peeled because it is not a tag: */
1584 /* ref_entry contains no peeled value because it is a symref: */
1585 PEEL_IS_SYMREF = -3,
1588 * ref_entry cannot be peeled because it is broken (i.e., the
1589 * symbolic reference cannot even be resolved to an object
1596 * Peel the named object; i.e., if the object is a tag, resolve the
1597 * tag recursively until a non-tag is found. If successful, store the
1598 * result to sha1 and return PEEL_PEELED. If the object is not a tag
1599 * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively,
1600 * and leave sha1 unchanged.
1602 static enum peel_status peel_object(const unsigned char *name, unsigned char *sha1)
1604 struct object *o = lookup_unknown_object(name);
1606 if (o->type == OBJ_NONE) {
1607 int type = sha1_object_info(name, NULL);
1608 if (type < 0 || !object_as_type(o, type, 0))
1609 return PEEL_INVALID;
1612 if (o->type != OBJ_TAG)
1613 return PEEL_NON_TAG;
1615 o = deref_tag_noverify(o);
1617 return PEEL_INVALID;
1619 hashcpy(sha1, o->sha1);
1624 * Peel the entry (if possible) and return its new peel_status. If
1625 * repeel is true, re-peel the entry even if there is an old peeled
1626 * value that is already stored in it.
1628 * It is OK to call this function with a packed reference entry that
1629 * might be stale and might even refer to an object that has since
1630 * been garbage-collected. In such a case, if the entry has
1631 * REF_KNOWS_PEELED then leave the status unchanged and return
1632 * PEEL_PEELED or PEEL_NON_TAG; otherwise, return PEEL_INVALID.
1634 static enum peel_status peel_entry(struct ref_entry *entry, int repeel)
1636 enum peel_status status;
1638 if (entry->flag & REF_KNOWS_PEELED) {
1640 entry->flag &= ~REF_KNOWS_PEELED;
1641 hashclr(entry->u.value.peeled);
1643 return is_null_sha1(entry->u.value.peeled) ?
1644 PEEL_NON_TAG : PEEL_PEELED;
1647 if (entry->flag & REF_ISBROKEN)
1649 if (entry->flag & REF_ISSYMREF)
1650 return PEEL_IS_SYMREF;
1652 status = peel_object(entry->u.value.sha1, entry->u.value.peeled);
1653 if (status == PEEL_PEELED || status == PEEL_NON_TAG)
1654 entry->flag |= REF_KNOWS_PEELED;
1658 int peel_ref(const char *refname, unsigned char *sha1)
1661 unsigned char base[20];
1663 if (current_ref && (current_ref->name == refname
1664 || !strcmp(current_ref->name, refname))) {
1665 if (peel_entry(current_ref, 0))
1667 hashcpy(sha1, current_ref->u.value.peeled);
1671 if (read_ref_full(refname, base, 1, &flag))
1675 * If the reference is packed, read its ref_entry from the
1676 * cache in the hope that we already know its peeled value.
1677 * We only try this optimization on packed references because
1678 * (a) forcing the filling of the loose reference cache could
1679 * be expensive and (b) loose references anyway usually do not
1680 * have REF_KNOWS_PEELED.
1682 if (flag & REF_ISPACKED) {
1683 struct ref_entry *r = get_packed_ref(refname);
1685 if (peel_entry(r, 0))
1687 hashcpy(sha1, r->u.value.peeled);
1692 return peel_object(base, sha1);
1695 struct warn_if_dangling_data {
1697 const char *refname;
1698 const struct string_list *refnames;
1699 const char *msg_fmt;
1702 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
1703 int flags, void *cb_data)
1705 struct warn_if_dangling_data *d = cb_data;
1706 const char *resolves_to;
1707 unsigned char junk[20];
1709 if (!(flags & REF_ISSYMREF))
1712 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
1715 ? strcmp(resolves_to, d->refname)
1716 : !string_list_has_string(d->refnames, resolves_to))) {
1720 fprintf(d->fp, d->msg_fmt, refname);
1725 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
1727 struct warn_if_dangling_data data;
1730 data.refname = refname;
1731 data.refnames = NULL;
1732 data.msg_fmt = msg_fmt;
1733 for_each_rawref(warn_if_dangling_symref, &data);
1736 void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames)
1738 struct warn_if_dangling_data data;
1741 data.refname = NULL;
1742 data.refnames = refnames;
1743 data.msg_fmt = msg_fmt;
1744 for_each_rawref(warn_if_dangling_symref, &data);
1748 * Call fn for each reference in the specified ref_cache, omitting
1749 * references not in the containing_dir of base. fn is called for all
1750 * references, including broken ones. If fn ever returns a non-zero
1751 * value, stop the iteration and return that value; otherwise, return
1754 static int do_for_each_entry(struct ref_cache *refs, const char *base,
1755 each_ref_entry_fn fn, void *cb_data)
1757 struct packed_ref_cache *packed_ref_cache;
1758 struct ref_dir *loose_dir;
1759 struct ref_dir *packed_dir;
1763 * We must make sure that all loose refs are read before accessing the
1764 * packed-refs file; this avoids a race condition in which loose refs
1765 * are migrated to the packed-refs file by a simultaneous process, but
1766 * our in-memory view is from before the migration. get_packed_ref_cache()
1767 * takes care of making sure our view is up to date with what is on
1770 loose_dir = get_loose_refs(refs);
1771 if (base && *base) {
1772 loose_dir = find_containing_dir(loose_dir, base, 0);
1775 prime_ref_dir(loose_dir);
1777 packed_ref_cache = get_packed_ref_cache(refs);
1778 acquire_packed_ref_cache(packed_ref_cache);
1779 packed_dir = get_packed_ref_dir(packed_ref_cache);
1780 if (base && *base) {
1781 packed_dir = find_containing_dir(packed_dir, base, 0);
1784 if (packed_dir && loose_dir) {
1785 sort_ref_dir(packed_dir);
1786 sort_ref_dir(loose_dir);
1787 retval = do_for_each_entry_in_dirs(
1788 packed_dir, loose_dir, fn, cb_data);
1789 } else if (packed_dir) {
1790 sort_ref_dir(packed_dir);
1791 retval = do_for_each_entry_in_dir(
1792 packed_dir, 0, fn, cb_data);
1793 } else if (loose_dir) {
1794 sort_ref_dir(loose_dir);
1795 retval = do_for_each_entry_in_dir(
1796 loose_dir, 0, fn, cb_data);
1799 release_packed_ref_cache(packed_ref_cache);
1804 * Call fn for each reference in the specified ref_cache for which the
1805 * refname begins with base. If trim is non-zero, then trim that many
1806 * characters off the beginning of each refname before passing the
1807 * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include
1808 * broken references in the iteration. If fn ever returns a non-zero
1809 * value, stop the iteration and return that value; otherwise, return
1812 static int do_for_each_ref(struct ref_cache *refs, const char *base,
1813 each_ref_fn fn, int trim, int flags, void *cb_data)
1815 struct ref_entry_cb data;
1820 data.cb_data = cb_data;
1822 return do_for_each_entry(refs, base, do_one_ref, &data);
1825 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
1827 unsigned char sha1[20];
1831 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
1832 return fn("HEAD", sha1, 0, cb_data);
1837 if (!read_ref_full("HEAD", sha1, 1, &flag))
1838 return fn("HEAD", sha1, flag, cb_data);
1843 int head_ref(each_ref_fn fn, void *cb_data)
1845 return do_head_ref(NULL, fn, cb_data);
1848 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1850 return do_head_ref(submodule, fn, cb_data);
1853 int for_each_ref(each_ref_fn fn, void *cb_data)
1855 return do_for_each_ref(&ref_cache, "", fn, 0, 0, cb_data);
1858 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1860 return do_for_each_ref(get_ref_cache(submodule), "", fn, 0, 0, cb_data);
1863 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1865 return do_for_each_ref(&ref_cache, prefix, fn, strlen(prefix), 0, cb_data);
1868 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1869 each_ref_fn fn, void *cb_data)
1871 return do_for_each_ref(get_ref_cache(submodule), prefix, fn, strlen(prefix), 0, cb_data);
1874 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
1876 return for_each_ref_in("refs/tags/", fn, cb_data);
1879 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1881 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1884 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
1886 return for_each_ref_in("refs/heads/", fn, cb_data);
1889 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1891 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1894 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
1896 return for_each_ref_in("refs/remotes/", fn, cb_data);
1899 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1901 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1904 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1906 return do_for_each_ref(&ref_cache, "refs/replace/", fn, 13, 0, cb_data);
1909 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1911 struct strbuf buf = STRBUF_INIT;
1913 unsigned char sha1[20];
1916 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
1917 if (!read_ref_full(buf.buf, sha1, 1, &flag))
1918 ret = fn(buf.buf, sha1, flag, cb_data);
1919 strbuf_release(&buf);
1924 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1926 struct strbuf buf = STRBUF_INIT;
1928 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1929 ret = do_for_each_ref(&ref_cache, buf.buf, fn, 0, 0, cb_data);
1930 strbuf_release(&buf);
1934 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1935 const char *prefix, void *cb_data)
1937 struct strbuf real_pattern = STRBUF_INIT;
1938 struct ref_filter filter;
1941 if (!prefix && !starts_with(pattern, "refs/"))
1942 strbuf_addstr(&real_pattern, "refs/");
1944 strbuf_addstr(&real_pattern, prefix);
1945 strbuf_addstr(&real_pattern, pattern);
1947 if (!has_glob_specials(pattern)) {
1948 /* Append implied '/' '*' if not present. */
1949 if (real_pattern.buf[real_pattern.len - 1] != '/')
1950 strbuf_addch(&real_pattern, '/');
1951 /* No need to check for '*', there is none. */
1952 strbuf_addch(&real_pattern, '*');
1955 filter.pattern = real_pattern.buf;
1957 filter.cb_data = cb_data;
1958 ret = for_each_ref(filter_refs, &filter);
1960 strbuf_release(&real_pattern);
1964 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1966 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1969 int for_each_rawref(each_ref_fn fn, void *cb_data)
1971 return do_for_each_ref(&ref_cache, "", fn, 0,
1972 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1975 const char *prettify_refname(const char *name)
1978 starts_with(name, "refs/heads/") ? 11 :
1979 starts_with(name, "refs/tags/") ? 10 :
1980 starts_with(name, "refs/remotes/") ? 13 :
1984 static const char *ref_rev_parse_rules[] = {
1989 "refs/remotes/%.*s",
1990 "refs/remotes/%.*s/HEAD",
1994 int refname_match(const char *abbrev_name, const char *full_name)
1997 const int abbrev_name_len = strlen(abbrev_name);
1999 for (p = ref_rev_parse_rules; *p; p++) {
2000 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
2008 /* This function should make sure errno is meaningful on error */
2009 static struct ref_lock *verify_lock(struct ref_lock *lock,
2010 const unsigned char *old_sha1, int mustexist)
2012 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
2013 int save_errno = errno;
2014 error("Can't verify ref %s", lock->ref_name);
2019 if (hashcmp(lock->old_sha1, old_sha1)) {
2020 error("Ref %s is at %s but expected %s", lock->ref_name,
2021 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
2029 static int remove_empty_directories(const char *file)
2031 /* we want to create a file but there is a directory there;
2032 * if that is an empty directory (or a directory that contains
2033 * only empty directories), remove them.
2036 int result, save_errno;
2038 strbuf_init(&path, 20);
2039 strbuf_addstr(&path, file);
2041 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
2044 strbuf_release(&path);
2051 * *string and *len will only be substituted, and *string returned (for
2052 * later free()ing) if the string passed in is a magic short-hand form
2055 static char *substitute_branch_name(const char **string, int *len)
2057 struct strbuf buf = STRBUF_INIT;
2058 int ret = interpret_branch_name(*string, *len, &buf);
2062 *string = strbuf_detach(&buf, &size);
2064 return (char *)*string;
2070 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
2072 char *last_branch = substitute_branch_name(&str, &len);
2077 for (p = ref_rev_parse_rules; *p; p++) {
2078 char fullref[PATH_MAX];
2079 unsigned char sha1_from_ref[20];
2080 unsigned char *this_result;
2083 this_result = refs_found ? sha1_from_ref : sha1;
2084 mksnpath(fullref, sizeof(fullref), *p, len, str);
2085 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
2089 if (!warn_ambiguous_refs)
2091 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
2092 warning("ignoring dangling symref %s.", fullref);
2093 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
2094 warning("ignoring broken ref %s.", fullref);
2101 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
2103 char *last_branch = substitute_branch_name(&str, &len);
2108 for (p = ref_rev_parse_rules; *p; p++) {
2109 unsigned char hash[20];
2110 char path[PATH_MAX];
2111 const char *ref, *it;
2113 mksnpath(path, sizeof(path), *p, len, str);
2114 ref = resolve_ref_unsafe(path, hash, 1, NULL);
2117 if (reflog_exists(path))
2119 else if (strcmp(ref, path) && reflog_exists(ref))
2123 if (!logs_found++) {
2125 hashcpy(sha1, hash);
2127 if (!warn_ambiguous_refs)
2135 * Locks a "refs/" ref returning the lock on success and NULL on failure.
2136 * On failure errno is set to something meaningful.
2138 static struct ref_lock *lock_ref_sha1_basic(const char *refname,
2139 const unsigned char *old_sha1,
2140 int flags, int *type_p)
2143 const char *orig_refname = refname;
2144 struct ref_lock *lock;
2147 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
2149 int attempts_remaining = 3;
2151 lock = xcalloc(1, sizeof(struct ref_lock));
2154 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
2155 if (!refname && errno == EISDIR) {
2156 /* we are trying to lock foo but we used to
2157 * have foo/bar which now does not exist;
2158 * it is normal for the empty directory 'foo'
2161 ref_file = git_path("%s", orig_refname);
2162 if (remove_empty_directories(ref_file)) {
2164 error("there are still refs under '%s'", orig_refname);
2167 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
2173 error("unable to resolve reference %s: %s",
2174 orig_refname, strerror(errno));
2177 missing = is_null_sha1(lock->old_sha1);
2178 /* When the ref did not exist and we are creating it,
2179 * make sure there is no existing ref that is packed
2180 * whose name begins with our refname, nor a ref whose
2181 * name is a proper prefix of our refname.
2184 !is_refname_available(refname, NULL, get_packed_refs(&ref_cache))) {
2185 last_errno = ENOTDIR;
2189 lock->lk = xcalloc(1, sizeof(struct lock_file));
2192 if (flags & REF_NODEREF) {
2193 refname = orig_refname;
2194 lflags |= LOCK_NODEREF;
2196 lock->ref_name = xstrdup(refname);
2197 lock->orig_ref_name = xstrdup(orig_refname);
2198 ref_file = git_path("%s", refname);
2200 lock->force_write = 1;
2201 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
2202 lock->force_write = 1;
2205 switch (safe_create_leading_directories(ref_file)) {
2207 break; /* success */
2209 if (--attempts_remaining > 0)
2214 error("unable to create directory for %s", ref_file);
2218 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
2219 if (lock->lock_fd < 0) {
2220 if (errno == ENOENT && --attempts_remaining > 0)
2222 * Maybe somebody just deleted one of the
2223 * directories leading to ref_file. Try
2228 unable_to_lock_die(ref_file, errno);
2230 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
2238 struct ref_lock *lock_any_ref_for_update(const char *refname,
2239 const unsigned char *old_sha1,
2240 int flags, int *type_p)
2242 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
2244 return lock_ref_sha1_basic(refname, old_sha1, flags, type_p);
2248 * Write an entry to the packed-refs file for the specified refname.
2249 * If peeled is non-NULL, write it as the entry's peeled value.
2251 static void write_packed_entry(FILE *fh, char *refname, unsigned char *sha1,
2252 unsigned char *peeled)
2254 fprintf_or_die(fh, "%s %s\n", sha1_to_hex(sha1), refname);
2256 fprintf_or_die(fh, "^%s\n", sha1_to_hex(peeled));
2260 * An each_ref_entry_fn that writes the entry to a packed-refs file.
2262 static int write_packed_entry_fn(struct ref_entry *entry, void *cb_data)
2264 enum peel_status peel_status = peel_entry(entry, 0);
2266 if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)
2267 error("internal error: %s is not a valid packed reference!",
2269 write_packed_entry(cb_data, entry->name, entry->u.value.sha1,
2270 peel_status == PEEL_PEELED ?
2271 entry->u.value.peeled : NULL);
2275 /* This should return a meaningful errno on failure */
2276 int lock_packed_refs(int flags)
2278 struct packed_ref_cache *packed_ref_cache;
2280 if (hold_lock_file_for_update(&packlock, git_path("packed-refs"), flags) < 0)
2283 * Get the current packed-refs while holding the lock. If the
2284 * packed-refs file has been modified since we last read it,
2285 * this will automatically invalidate the cache and re-read
2286 * the packed-refs file.
2288 packed_ref_cache = get_packed_ref_cache(&ref_cache);
2289 packed_ref_cache->lock = &packlock;
2290 /* Increment the reference count to prevent it from being freed: */
2291 acquire_packed_ref_cache(packed_ref_cache);
2296 * Commit the packed refs changes.
2297 * On error we must make sure that errno contains a meaningful value.
2299 int commit_packed_refs(void)
2301 struct packed_ref_cache *packed_ref_cache =
2302 get_packed_ref_cache(&ref_cache);
2307 if (!packed_ref_cache->lock)
2308 die("internal error: packed-refs not locked");
2310 out = fdopen(packed_ref_cache->lock->fd, "w");
2312 die_errno("unable to fdopen packed-refs descriptor");
2314 fprintf_or_die(out, "%s", PACKED_REFS_HEADER);
2315 do_for_each_entry_in_dir(get_packed_ref_dir(packed_ref_cache),
2316 0, write_packed_entry_fn, out);
2318 die_errno("write error");
2319 packed_ref_cache->lock->fd = -1;
2321 if (commit_lock_file(packed_ref_cache->lock)) {
2325 packed_ref_cache->lock = NULL;
2326 release_packed_ref_cache(packed_ref_cache);
2331 void rollback_packed_refs(void)
2333 struct packed_ref_cache *packed_ref_cache =
2334 get_packed_ref_cache(&ref_cache);
2336 if (!packed_ref_cache->lock)
2337 die("internal error: packed-refs not locked");
2338 rollback_lock_file(packed_ref_cache->lock);
2339 packed_ref_cache->lock = NULL;
2340 release_packed_ref_cache(packed_ref_cache);
2341 clear_packed_ref_cache(&ref_cache);
2344 struct ref_to_prune {
2345 struct ref_to_prune *next;
2346 unsigned char sha1[20];
2347 char name[FLEX_ARRAY];
2350 struct pack_refs_cb_data {
2352 struct ref_dir *packed_refs;
2353 struct ref_to_prune *ref_to_prune;
2357 * An each_ref_entry_fn that is run over loose references only. If
2358 * the loose reference can be packed, add an entry in the packed ref
2359 * cache. If the reference should be pruned, also add it to
2360 * ref_to_prune in the pack_refs_cb_data.
2362 static int pack_if_possible_fn(struct ref_entry *entry, void *cb_data)
2364 struct pack_refs_cb_data *cb = cb_data;
2365 enum peel_status peel_status;
2366 struct ref_entry *packed_entry;
2367 int is_tag_ref = starts_with(entry->name, "refs/tags/");
2369 /* ALWAYS pack tags */
2370 if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref)
2373 /* Do not pack symbolic or broken refs: */
2374 if ((entry->flag & REF_ISSYMREF) || !ref_resolves_to_object(entry))
2377 /* Add a packed ref cache entry equivalent to the loose entry. */
2378 peel_status = peel_entry(entry, 1);
2379 if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)
2380 die("internal error peeling reference %s (%s)",
2381 entry->name, sha1_to_hex(entry->u.value.sha1));
2382 packed_entry = find_ref(cb->packed_refs, entry->name);
2384 /* Overwrite existing packed entry with info from loose entry */
2385 packed_entry->flag = REF_ISPACKED | REF_KNOWS_PEELED;
2386 hashcpy(packed_entry->u.value.sha1, entry->u.value.sha1);
2388 packed_entry = create_ref_entry(entry->name, entry->u.value.sha1,
2389 REF_ISPACKED | REF_KNOWS_PEELED, 0);
2390 add_ref(cb->packed_refs, packed_entry);
2392 hashcpy(packed_entry->u.value.peeled, entry->u.value.peeled);
2394 /* Schedule the loose reference for pruning if requested. */
2395 if ((cb->flags & PACK_REFS_PRUNE)) {
2396 int namelen = strlen(entry->name) + 1;
2397 struct ref_to_prune *n = xcalloc(1, sizeof(*n) + namelen);
2398 hashcpy(n->sha1, entry->u.value.sha1);
2399 strcpy(n->name, entry->name);
2400 n->next = cb->ref_to_prune;
2401 cb->ref_to_prune = n;
2407 * Remove empty parents, but spare refs/ and immediate subdirs.
2408 * Note: munges *name.
2410 static void try_remove_empty_parents(char *name)
2415 for (i = 0; i < 2; i++) { /* refs/{heads,tags,...}/ */
2416 while (*p && *p != '/')
2418 /* tolerate duplicate slashes; see check_refname_format() */
2422 for (q = p; *q; q++)
2425 while (q > p && *q != '/')
2427 while (q > p && *(q-1) == '/')
2432 if (rmdir(git_path("%s", name)))
2437 /* make sure nobody touched the ref, and unlink */
2438 static void prune_ref(struct ref_to_prune *r)
2440 struct ref_transaction *transaction;
2441 struct strbuf err = STRBUF_INIT;
2443 if (check_refname_format(r->name, 0))
2446 transaction = ref_transaction_begin(&err);
2448 ref_transaction_delete(transaction, r->name, r->sha1,
2449 REF_ISPRUNING, 1, &err) ||
2450 ref_transaction_commit(transaction, NULL, &err)) {
2451 ref_transaction_free(transaction);
2452 error("%s", err.buf);
2453 strbuf_release(&err);
2456 ref_transaction_free(transaction);
2457 strbuf_release(&err);
2458 try_remove_empty_parents(r->name);
2461 static void prune_refs(struct ref_to_prune *r)
2469 int pack_refs(unsigned int flags)
2471 struct pack_refs_cb_data cbdata;
2473 memset(&cbdata, 0, sizeof(cbdata));
2474 cbdata.flags = flags;
2476 lock_packed_refs(LOCK_DIE_ON_ERROR);
2477 cbdata.packed_refs = get_packed_refs(&ref_cache);
2479 do_for_each_entry_in_dir(get_loose_refs(&ref_cache), 0,
2480 pack_if_possible_fn, &cbdata);
2482 if (commit_packed_refs())
2483 die_errno("unable to overwrite old ref-pack file");
2485 prune_refs(cbdata.ref_to_prune);
2490 * If entry is no longer needed in packed-refs, add it to the string
2491 * list pointed to by cb_data. Reasons for deleting entries:
2493 * - Entry is broken.
2494 * - Entry is overridden by a loose ref.
2495 * - Entry does not point at a valid object.
2497 * In the first and third cases, also emit an error message because these
2498 * are indications of repository corruption.
2500 static int curate_packed_ref_fn(struct ref_entry *entry, void *cb_data)
2502 struct string_list *refs_to_delete = cb_data;
2504 if (entry->flag & REF_ISBROKEN) {
2505 /* This shouldn't happen to packed refs. */
2506 error("%s is broken!", entry->name);
2507 string_list_append(refs_to_delete, entry->name);
2510 if (!has_sha1_file(entry->u.value.sha1)) {
2511 unsigned char sha1[20];
2514 if (read_ref_full(entry->name, sha1, 0, &flags))
2515 /* We should at least have found the packed ref. */
2516 die("Internal error");
2517 if ((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED)) {
2519 * This packed reference is overridden by a
2520 * loose reference, so it is OK that its value
2521 * is no longer valid; for example, it might
2522 * refer to an object that has been garbage
2523 * collected. For this purpose we don't even
2524 * care whether the loose reference itself is
2525 * invalid, broken, symbolic, etc. Silently
2526 * remove the packed reference.
2528 string_list_append(refs_to_delete, entry->name);
2532 * There is no overriding loose reference, so the fact
2533 * that this reference doesn't refer to a valid object
2534 * indicates some kind of repository corruption.
2535 * Report the problem, then omit the reference from
2538 error("%s does not point to a valid object!", entry->name);
2539 string_list_append(refs_to_delete, entry->name);
2546 int repack_without_refs(const char **refnames, int n, struct strbuf *err)
2548 struct ref_dir *packed;
2549 struct string_list refs_to_delete = STRING_LIST_INIT_DUP;
2550 struct string_list_item *ref_to_delete;
2551 int i, ret, removed = 0;
2553 /* Look for a packed ref */
2554 for (i = 0; i < n; i++)
2555 if (get_packed_ref(refnames[i]))
2558 /* Avoid locking if we have nothing to do */
2560 return 0; /* no refname exists in packed refs */
2562 if (lock_packed_refs(0)) {
2564 unable_to_lock_message(git_path("packed-refs"), errno,
2568 unable_to_lock_error(git_path("packed-refs"), errno);
2569 return error("cannot delete '%s' from packed refs", refnames[i]);
2571 packed = get_packed_refs(&ref_cache);
2573 /* Remove refnames from the cache */
2574 for (i = 0; i < n; i++)
2575 if (remove_entry(packed, refnames[i]) != -1)
2579 * All packed entries disappeared while we were
2580 * acquiring the lock.
2582 rollback_packed_refs();
2586 /* Remove any other accumulated cruft */
2587 do_for_each_entry_in_dir(packed, 0, curate_packed_ref_fn, &refs_to_delete);
2588 for_each_string_list_item(ref_to_delete, &refs_to_delete) {
2589 if (remove_entry(packed, ref_to_delete->string) == -1)
2590 die("internal error");
2593 /* Write what remains */
2594 ret = commit_packed_refs();
2596 strbuf_addf(err, "unable to overwrite old ref-pack file: %s",
2601 static int delete_ref_loose(struct ref_lock *lock, int flag)
2603 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
2605 int err, i = strlen(lock->lk->filename) - 5; /* .lock */
2607 lock->lk->filename[i] = 0;
2608 err = unlink_or_warn(lock->lk->filename);
2609 lock->lk->filename[i] = '.';
2610 if (err && errno != ENOENT)
2616 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
2618 struct ref_transaction *transaction;
2619 struct strbuf err = STRBUF_INIT;
2621 transaction = ref_transaction_begin(&err);
2623 ref_transaction_delete(transaction, refname, sha1, delopt,
2624 sha1 && !is_null_sha1(sha1), &err) ||
2625 ref_transaction_commit(transaction, NULL, &err)) {
2626 error("%s", err.buf);
2627 ref_transaction_free(transaction);
2628 strbuf_release(&err);
2631 ref_transaction_free(transaction);
2632 strbuf_release(&err);
2637 * People using contrib's git-new-workdir have .git/logs/refs ->
2638 * /some/other/path/.git/logs/refs, and that may live on another device.
2640 * IOW, to avoid cross device rename errors, the temporary renamed log must
2641 * live into logs/refs.
2643 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
2645 static int rename_tmp_log(const char *newrefname)
2647 int attempts_remaining = 4;
2650 switch (safe_create_leading_directories(git_path("logs/%s", newrefname))) {
2652 break; /* success */
2654 if (--attempts_remaining > 0)
2658 error("unable to create directory for %s", newrefname);
2662 if (rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
2663 if ((errno==EISDIR || errno==ENOTDIR) && --attempts_remaining > 0) {
2665 * rename(a, b) when b is an existing
2666 * directory ought to result in ISDIR, but
2667 * Solaris 5.8 gives ENOTDIR. Sheesh.
2669 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
2670 error("Directory not empty: logs/%s", newrefname);
2674 } else if (errno == ENOENT && --attempts_remaining > 0) {
2676 * Maybe another process just deleted one of
2677 * the directories in the path to newrefname.
2678 * Try again from the beginning.
2682 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
2683 newrefname, strerror(errno));
2690 int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
2692 unsigned char sha1[20], orig_sha1[20];
2693 int flag = 0, logmoved = 0;
2694 struct ref_lock *lock;
2695 struct stat loginfo;
2696 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
2697 const char *symref = NULL;
2699 if (log && S_ISLNK(loginfo.st_mode))
2700 return error("reflog for %s is a symlink", oldrefname);
2702 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
2703 if (flag & REF_ISSYMREF)
2704 return error("refname %s is a symbolic ref, renaming it is not supported",
2707 return error("refname %s not found", oldrefname);
2709 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(&ref_cache)))
2712 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(&ref_cache)))
2715 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
2716 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
2717 oldrefname, strerror(errno));
2719 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
2720 error("unable to delete old %s", oldrefname);
2724 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
2725 delete_ref(newrefname, sha1, REF_NODEREF)) {
2726 if (errno==EISDIR) {
2727 if (remove_empty_directories(git_path("%s", newrefname))) {
2728 error("Directory not empty: %s", newrefname);
2732 error("unable to delete existing %s", newrefname);
2737 if (log && rename_tmp_log(newrefname))
2742 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
2744 error("unable to lock %s for update", newrefname);
2747 lock->force_write = 1;
2748 hashcpy(lock->old_sha1, orig_sha1);
2749 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
2750 error("unable to write current sha1 into %s", newrefname);
2757 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
2759 error("unable to lock %s for rollback", oldrefname);
2763 lock->force_write = 1;
2764 flag = log_all_ref_updates;
2765 log_all_ref_updates = 0;
2766 if (write_ref_sha1(lock, orig_sha1, NULL))
2767 error("unable to write current sha1 into %s", oldrefname);
2768 log_all_ref_updates = flag;
2771 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
2772 error("unable to restore logfile %s from %s: %s",
2773 oldrefname, newrefname, strerror(errno));
2774 if (!logmoved && log &&
2775 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
2776 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
2777 oldrefname, strerror(errno));
2782 int close_ref(struct ref_lock *lock)
2784 if (close_lock_file(lock->lk))
2790 int commit_ref(struct ref_lock *lock)
2792 if (commit_lock_file(lock->lk))
2798 void unlock_ref(struct ref_lock *lock)
2800 /* Do not free lock->lk -- atexit() still looks at them */
2802 rollback_lock_file(lock->lk);
2803 free(lock->ref_name);
2804 free(lock->orig_ref_name);
2809 * copy the reflog message msg to buf, which has been allocated sufficiently
2810 * large, while cleaning up the whitespaces. Especially, convert LF to space,
2811 * because reflog file is one line per entry.
2813 static int copy_msg(char *buf, const char *msg)
2820 while ((c = *msg++)) {
2821 if (wasspace && isspace(c))
2823 wasspace = isspace(c);
2828 while (buf < cp && isspace(cp[-1]))
2834 /* This function must set a meaningful errno on failure */
2835 int log_ref_setup(const char *refname, char *logfile, int bufsize)
2837 int logfd, oflags = O_APPEND | O_WRONLY;
2839 git_snpath(logfile, bufsize, "logs/%s", refname);
2840 if (log_all_ref_updates &&
2841 (starts_with(refname, "refs/heads/") ||
2842 starts_with(refname, "refs/remotes/") ||
2843 starts_with(refname, "refs/notes/") ||
2844 !strcmp(refname, "HEAD"))) {
2845 if (safe_create_leading_directories(logfile) < 0) {
2846 int save_errno = errno;
2847 error("unable to create directory for %s", logfile);
2854 logfd = open(logfile, oflags, 0666);
2856 if (!(oflags & O_CREAT) && errno == ENOENT)
2859 if ((oflags & O_CREAT) && errno == EISDIR) {
2860 if (remove_empty_directories(logfile)) {
2861 int save_errno = errno;
2862 error("There are still logs under '%s'",
2867 logfd = open(logfile, oflags, 0666);
2871 int save_errno = errno;
2872 error("Unable to append to %s: %s", logfile,
2879 adjust_shared_perm(logfile);
2884 static int log_ref_write(const char *refname, const unsigned char *old_sha1,
2885 const unsigned char *new_sha1, const char *msg)
2887 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
2888 unsigned maxlen, len;
2890 char log_file[PATH_MAX];
2892 const char *committer;
2894 if (log_all_ref_updates < 0)
2895 log_all_ref_updates = !is_bare_repository();
2897 result = log_ref_setup(refname, log_file, sizeof(log_file));
2901 logfd = open(log_file, oflags);
2904 msglen = msg ? strlen(msg) : 0;
2905 committer = git_committer_info(0);
2906 maxlen = strlen(committer) + msglen + 100;
2907 logrec = xmalloc(maxlen);
2908 len = sprintf(logrec, "%s %s %s\n",
2909 sha1_to_hex(old_sha1),
2910 sha1_to_hex(new_sha1),
2913 len += copy_msg(logrec + len - 1, msg) - 1;
2914 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
2916 if (written != len) {
2917 int save_errno = errno;
2919 error("Unable to append to %s", log_file);
2924 int save_errno = errno;
2925 error("Unable to append to %s", log_file);
2932 int is_branch(const char *refname)
2934 return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
2937 /* This function must return a meaningful errno */
2938 int write_ref_sha1(struct ref_lock *lock,
2939 const unsigned char *sha1, const char *logmsg)
2941 static char term = '\n';
2948 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
2952 o = parse_object(sha1);
2954 error("Trying to write ref %s with nonexistent object %s",
2955 lock->ref_name, sha1_to_hex(sha1));
2960 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
2961 error("Trying to write non-commit object %s to branch %s",
2962 sha1_to_hex(sha1), lock->ref_name);
2967 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
2968 write_in_full(lock->lock_fd, &term, 1) != 1 ||
2969 close_ref(lock) < 0) {
2970 int save_errno = errno;
2971 error("Couldn't write %s", lock->lk->filename);
2976 clear_loose_ref_cache(&ref_cache);
2977 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
2978 (strcmp(lock->ref_name, lock->orig_ref_name) &&
2979 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
2983 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
2985 * Special hack: If a branch is updated directly and HEAD
2986 * points to it (may happen on the remote side of a push
2987 * for example) then logically the HEAD reflog should be
2989 * A generic solution implies reverse symref information,
2990 * but finding all symrefs pointing to the given branch
2991 * would be rather costly for this rare event (the direct
2992 * update of a branch) to be worth it. So let's cheat and
2993 * check with HEAD only which should cover 99% of all usage
2994 * scenarios (even 100% of the default ones).
2996 unsigned char head_sha1[20];
2998 const char *head_ref;
2999 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
3000 if (head_ref && (head_flag & REF_ISSYMREF) &&
3001 !strcmp(head_ref, lock->ref_name))
3002 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
3004 if (commit_ref(lock)) {
3005 error("Couldn't set %s", lock->ref_name);
3013 int create_symref(const char *ref_target, const char *refs_heads_master,
3016 const char *lockpath;
3018 int fd, len, written;
3019 char *git_HEAD = git_pathdup("%s", ref_target);
3020 unsigned char old_sha1[20], new_sha1[20];
3022 if (logmsg && read_ref(ref_target, old_sha1))
3025 if (safe_create_leading_directories(git_HEAD) < 0)
3026 return error("unable to create directory for %s", git_HEAD);
3028 #ifndef NO_SYMLINK_HEAD
3029 if (prefer_symlink_refs) {
3031 if (!symlink(refs_heads_master, git_HEAD))
3033 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
3037 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
3038 if (sizeof(ref) <= len) {
3039 error("refname too long: %s", refs_heads_master);
3040 goto error_free_return;
3042 lockpath = mkpath("%s.lock", git_HEAD);
3043 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
3045 error("Unable to open %s for writing", lockpath);
3046 goto error_free_return;
3048 written = write_in_full(fd, ref, len);
3049 if (close(fd) != 0 || written != len) {
3050 error("Unable to write to %s", lockpath);
3051 goto error_unlink_return;
3053 if (rename(lockpath, git_HEAD) < 0) {
3054 error("Unable to create %s", git_HEAD);
3055 goto error_unlink_return;
3057 if (adjust_shared_perm(git_HEAD)) {
3058 error("Unable to fix permissions on %s", lockpath);
3059 error_unlink_return:
3060 unlink_or_warn(lockpath);
3066 #ifndef NO_SYMLINK_HEAD
3069 if (logmsg && !read_ref(refs_heads_master, new_sha1))
3070 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
3076 struct read_ref_at_cb {
3077 const char *refname;
3078 unsigned long at_time;
3081 unsigned char *sha1;
3084 unsigned char osha1[20];
3085 unsigned char nsha1[20];
3089 unsigned long *cutoff_time;
3094 static int read_ref_at_ent(unsigned char *osha1, unsigned char *nsha1,
3095 const char *email, unsigned long timestamp, int tz,
3096 const char *message, void *cb_data)
3098 struct read_ref_at_cb *cb = cb_data;
3102 cb->date = timestamp;
3104 if (timestamp <= cb->at_time || cb->cnt == 0) {
3106 *cb->msg = xstrdup(message);
3107 if (cb->cutoff_time)
3108 *cb->cutoff_time = timestamp;
3110 *cb->cutoff_tz = tz;
3112 *cb->cutoff_cnt = cb->reccnt - 1;
3114 * we have not yet updated cb->[n|o]sha1 so they still
3115 * hold the values for the previous record.
3117 if (!is_null_sha1(cb->osha1)) {
3118 hashcpy(cb->sha1, nsha1);
3119 if (hashcmp(cb->osha1, nsha1))
3120 warning("Log for ref %s has gap after %s.",
3121 cb->refname, show_date(cb->date, cb->tz, DATE_RFC2822));
3123 else if (cb->date == cb->at_time)
3124 hashcpy(cb->sha1, nsha1);
3125 else if (hashcmp(nsha1, cb->sha1))
3126 warning("Log for ref %s unexpectedly ended on %s.",
3127 cb->refname, show_date(cb->date, cb->tz,
3129 hashcpy(cb->osha1, osha1);
3130 hashcpy(cb->nsha1, nsha1);
3134 hashcpy(cb->osha1, osha1);
3135 hashcpy(cb->nsha1, nsha1);
3141 static int read_ref_at_ent_oldest(unsigned char *osha1, unsigned char *nsha1,
3142 const char *email, unsigned long timestamp,
3143 int tz, const char *message, void *cb_data)
3145 struct read_ref_at_cb *cb = cb_data;
3148 *cb->msg = xstrdup(message);
3149 if (cb->cutoff_time)
3150 *cb->cutoff_time = timestamp;
3152 *cb->cutoff_tz = tz;
3154 *cb->cutoff_cnt = cb->reccnt;
3155 hashcpy(cb->sha1, osha1);
3156 if (is_null_sha1(cb->sha1))
3157 hashcpy(cb->sha1, nsha1);
3158 /* We just want the first entry */
3162 int read_ref_at(const char *refname, unsigned int flags, unsigned long at_time, int cnt,
3163 unsigned char *sha1, char **msg,
3164 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
3166 struct read_ref_at_cb cb;
3168 memset(&cb, 0, sizeof(cb));
3169 cb.refname = refname;
3170 cb.at_time = at_time;
3173 cb.cutoff_time = cutoff_time;
3174 cb.cutoff_tz = cutoff_tz;
3175 cb.cutoff_cnt = cutoff_cnt;
3178 for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
3181 if (flags & GET_SHA1_QUIETLY)
3184 die("Log for %s is empty.", refname);
3189 for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
3194 int reflog_exists(const char *refname)
3198 return !lstat(git_path("logs/%s", refname), &st) &&
3199 S_ISREG(st.st_mode);
3202 int delete_reflog(const char *refname)
3204 return remove_path(git_path("logs/%s", refname));
3207 static int show_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn, void *cb_data)
3209 unsigned char osha1[20], nsha1[20];
3210 char *email_end, *message;
3211 unsigned long timestamp;
3214 /* old SP new SP name <email> SP time TAB msg LF */
3215 if (sb->len < 83 || sb->buf[sb->len - 1] != '\n' ||
3216 get_sha1_hex(sb->buf, osha1) || sb->buf[40] != ' ' ||
3217 get_sha1_hex(sb->buf + 41, nsha1) || sb->buf[81] != ' ' ||
3218 !(email_end = strchr(sb->buf + 82, '>')) ||
3219 email_end[1] != ' ' ||
3220 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
3221 !message || message[0] != ' ' ||
3222 (message[1] != '+' && message[1] != '-') ||
3223 !isdigit(message[2]) || !isdigit(message[3]) ||
3224 !isdigit(message[4]) || !isdigit(message[5]))
3225 return 0; /* corrupt? */
3226 email_end[1] = '\0';
3227 tz = strtol(message + 1, NULL, 10);
3228 if (message[6] != '\t')
3232 return fn(osha1, nsha1, sb->buf + 82, timestamp, tz, message, cb_data);
3235 static char *find_beginning_of_line(char *bob, char *scan)
3237 while (bob < scan && *(--scan) != '\n')
3238 ; /* keep scanning backwards */
3240 * Return either beginning of the buffer, or LF at the end of
3241 * the previous line.
3246 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data)
3248 struct strbuf sb = STRBUF_INIT;
3251 int ret = 0, at_tail = 1;
3253 logfp = fopen(git_path("logs/%s", refname), "r");
3257 /* Jump to the end */
3258 if (fseek(logfp, 0, SEEK_END) < 0)
3259 return error("cannot seek back reflog for %s: %s",
3260 refname, strerror(errno));
3262 while (!ret && 0 < pos) {
3268 /* Fill next block from the end */
3269 cnt = (sizeof(buf) < pos) ? sizeof(buf) : pos;
3270 if (fseek(logfp, pos - cnt, SEEK_SET))
3271 return error("cannot seek back reflog for %s: %s",
3272 refname, strerror(errno));
3273 nread = fread(buf, cnt, 1, logfp);
3275 return error("cannot read %d bytes from reflog for %s: %s",
3276 cnt, refname, strerror(errno));
3279 scanp = endp = buf + cnt;
3280 if (at_tail && scanp[-1] == '\n')
3281 /* Looking at the final LF at the end of the file */
3285 while (buf < scanp) {
3287 * terminating LF of the previous line, or the beginning
3292 bp = find_beginning_of_line(buf, scanp);
3295 strbuf_splice(&sb, 0, 0, buf, endp - buf);
3297 break; /* need to fill another block */
3298 scanp = buf - 1; /* leave loop */
3301 * (bp + 1) thru endp is the beginning of the
3302 * current line we have in sb
3304 strbuf_splice(&sb, 0, 0, bp + 1, endp - (bp + 1));
3308 ret = show_one_reflog_ent(&sb, fn, cb_data);
3316 ret = show_one_reflog_ent(&sb, fn, cb_data);
3319 strbuf_release(&sb);
3323 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
3326 struct strbuf sb = STRBUF_INIT;
3329 logfp = fopen(git_path("logs/%s", refname), "r");
3333 while (!ret && !strbuf_getwholeline(&sb, logfp, '\n'))
3334 ret = show_one_reflog_ent(&sb, fn, cb_data);
3336 strbuf_release(&sb);
3340 * Call fn for each reflog in the namespace indicated by name. name
3341 * must be empty or end with '/'. Name will be used as a scratch
3342 * space, but its contents will be restored before return.
3344 static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)
3346 DIR *d = opendir(git_path("logs/%s", name->buf));
3349 int oldlen = name->len;
3352 return name->len ? errno : 0;
3354 while ((de = readdir(d)) != NULL) {
3357 if (de->d_name[0] == '.')
3359 if (ends_with(de->d_name, ".lock"))
3361 strbuf_addstr(name, de->d_name);
3362 if (stat(git_path("logs/%s", name->buf), &st) < 0) {
3363 ; /* silently ignore */
3365 if (S_ISDIR(st.st_mode)) {
3366 strbuf_addch(name, '/');
3367 retval = do_for_each_reflog(name, fn, cb_data);
3369 unsigned char sha1[20];
3370 if (read_ref_full(name->buf, sha1, 0, NULL))
3371 retval = error("bad ref for %s", name->buf);
3373 retval = fn(name->buf, sha1, 0, cb_data);
3378 strbuf_setlen(name, oldlen);
3384 int for_each_reflog(each_ref_fn fn, void *cb_data)
3388 strbuf_init(&name, PATH_MAX);
3389 retval = do_for_each_reflog(&name, fn, cb_data);
3390 strbuf_release(&name);
3395 * Information needed for a single ref update. Set new_sha1 to the
3396 * new value or to zero to delete the ref. To check the old value
3397 * while locking the ref, set have_old to 1 and set old_sha1 to the
3398 * value or to zero to ensure the ref does not exist before update.
3401 unsigned char new_sha1[20];
3402 unsigned char old_sha1[20];
3403 int flags; /* REF_NODEREF? */
3404 int have_old; /* 1 if old_sha1 is valid, 0 otherwise */
3405 struct ref_lock *lock;
3407 const char refname[FLEX_ARRAY];
3411 * Transaction states.
3412 * OPEN: The transaction is in a valid state and can accept new updates.
3413 * An OPEN transaction can be committed.
3414 * CLOSED: A closed transaction is no longer active and no other operations
3415 * than free can be used on it in this state.
3416 * A transaction can either become closed by successfully committing
3417 * an active transaction or if there is a failure while building
3418 * the transaction thus rendering it failed/inactive.
3420 enum ref_transaction_state {
3421 REF_TRANSACTION_OPEN = 0,
3422 REF_TRANSACTION_CLOSED = 1
3426 * Data structure for holding a reference transaction, which can
3427 * consist of checks and updates to multiple references, carried out
3428 * as atomically as possible. This structure is opaque to callers.
3430 struct ref_transaction {
3431 struct ref_update **updates;
3434 enum ref_transaction_state state;
3437 struct ref_transaction *ref_transaction_begin(struct strbuf *err)
3439 return xcalloc(1, sizeof(struct ref_transaction));
3442 void ref_transaction_free(struct ref_transaction *transaction)
3449 for (i = 0; i < transaction->nr; i++)
3450 free(transaction->updates[i]);
3452 free(transaction->updates);
3456 static struct ref_update *add_update(struct ref_transaction *transaction,
3457 const char *refname)
3459 size_t len = strlen(refname);
3460 struct ref_update *update = xcalloc(1, sizeof(*update) + len + 1);
3462 strcpy((char *)update->refname, refname);
3463 ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
3464 transaction->updates[transaction->nr++] = update;
3468 int ref_transaction_update(struct ref_transaction *transaction,
3469 const char *refname,
3470 const unsigned char *new_sha1,
3471 const unsigned char *old_sha1,
3472 int flags, int have_old,
3475 struct ref_update *update;
3477 if (transaction->state != REF_TRANSACTION_OPEN)
3478 die("BUG: update called for transaction that is not open");
3480 if (have_old && !old_sha1)
3481 die("BUG: have_old is true but old_sha1 is NULL");
3483 update = add_update(transaction, refname);
3484 hashcpy(update->new_sha1, new_sha1);
3485 update->flags = flags;
3486 update->have_old = have_old;
3488 hashcpy(update->old_sha1, old_sha1);
3492 int ref_transaction_create(struct ref_transaction *transaction,
3493 const char *refname,
3494 const unsigned char *new_sha1,
3498 struct ref_update *update;
3500 if (transaction->state != REF_TRANSACTION_OPEN)
3501 die("BUG: create called for transaction that is not open");
3503 if (!new_sha1 || is_null_sha1(new_sha1))
3504 die("BUG: create ref with null new_sha1");
3506 update = add_update(transaction, refname);
3508 hashcpy(update->new_sha1, new_sha1);
3509 hashclr(update->old_sha1);
3510 update->flags = flags;
3511 update->have_old = 1;
3515 int ref_transaction_delete(struct ref_transaction *transaction,
3516 const char *refname,
3517 const unsigned char *old_sha1,
3518 int flags, int have_old,
3521 struct ref_update *update;
3523 if (transaction->state != REF_TRANSACTION_OPEN)
3524 die("BUG: delete called for transaction that is not open");
3526 if (have_old && !old_sha1)
3527 die("BUG: have_old is true but old_sha1 is NULL");
3529 update = add_update(transaction, refname);
3530 update->flags = flags;
3531 update->have_old = have_old;
3533 assert(!is_null_sha1(old_sha1));
3534 hashcpy(update->old_sha1, old_sha1);
3539 int update_ref(const char *action, const char *refname,
3540 const unsigned char *sha1, const unsigned char *oldval,
3541 int flags, enum action_on_err onerr)
3543 struct ref_transaction *t;
3544 struct strbuf err = STRBUF_INIT;
3546 t = ref_transaction_begin(&err);
3548 ref_transaction_update(t, refname, sha1, oldval, flags,
3550 ref_transaction_commit(t, action, &err)) {
3551 const char *str = "update_ref failed for ref '%s': %s";
3553 ref_transaction_free(t);
3555 case UPDATE_REFS_MSG_ON_ERR:
3556 error(str, refname, err.buf);
3558 case UPDATE_REFS_DIE_ON_ERR:
3559 die(str, refname, err.buf);
3561 case UPDATE_REFS_QUIET_ON_ERR:
3564 strbuf_release(&err);
3567 strbuf_release(&err);
3568 ref_transaction_free(t);
3572 static int ref_update_compare(const void *r1, const void *r2)
3574 const struct ref_update * const *u1 = r1;
3575 const struct ref_update * const *u2 = r2;
3576 return strcmp((*u1)->refname, (*u2)->refname);
3579 static int ref_update_reject_duplicates(struct ref_update **updates, int n,
3583 for (i = 1; i < n; i++)
3584 if (!strcmp(updates[i - 1]->refname, updates[i]->refname)) {
3586 "Multiple updates for ref '%s' not allowed.";
3588 strbuf_addf(err, str, updates[i]->refname);
3595 int ref_transaction_commit(struct ref_transaction *transaction,
3596 const char *msg, struct strbuf *err)
3598 int ret = 0, delnum = 0, i;
3599 const char **delnames;
3600 int n = transaction->nr;
3601 struct ref_update **updates = transaction->updates;
3603 if (transaction->state != REF_TRANSACTION_OPEN)
3604 die("BUG: commit called for transaction that is not open");
3607 transaction->state = REF_TRANSACTION_CLOSED;
3611 /* Allocate work space */
3612 delnames = xmalloc(sizeof(*delnames) * n);
3614 /* Copy, sort, and reject duplicate refs */
3615 qsort(updates, n, sizeof(*updates), ref_update_compare);
3616 ret = ref_update_reject_duplicates(updates, n, err);
3620 /* Acquire all locks while verifying old values */
3621 for (i = 0; i < n; i++) {
3622 struct ref_update *update = updates[i];
3624 update->lock = lock_any_ref_for_update(update->refname,
3630 if (!update->lock) {
3632 strbuf_addf(err, "Cannot lock the ref '%s'.",
3639 /* Perform updates first so live commits remain referenced */
3640 for (i = 0; i < n; i++) {
3641 struct ref_update *update = updates[i];
3643 if (!is_null_sha1(update->new_sha1)) {
3644 ret = write_ref_sha1(update->lock, update->new_sha1,
3646 update->lock = NULL; /* freed by write_ref_sha1 */
3649 strbuf_addf(err, "Cannot update the ref '%s'.",
3656 /* Perform deletes now that updates are safely completed */
3657 for (i = 0; i < n; i++) {
3658 struct ref_update *update = updates[i];
3661 ret |= delete_ref_loose(update->lock, update->type);
3662 if (!(update->flags & REF_ISPRUNING))
3663 delnames[delnum++] = update->lock->ref_name;
3667 ret |= repack_without_refs(delnames, delnum, err);
3668 for (i = 0; i < delnum; i++)
3669 unlink_or_warn(git_path("logs/%s", delnames[i]));
3670 clear_loose_ref_cache(&ref_cache);
3673 transaction->state = REF_TRANSACTION_CLOSED;
3675 for (i = 0; i < n; i++)
3676 if (updates[i]->lock)
3677 unlock_ref(updates[i]->lock);
3682 char *shorten_unambiguous_ref(const char *refname, int strict)
3685 static char **scanf_fmts;
3686 static int nr_rules;
3691 * Pre-generate scanf formats from ref_rev_parse_rules[].
3692 * Generate a format suitable for scanf from a
3693 * ref_rev_parse_rules rule by interpolating "%s" at the
3694 * location of the "%.*s".
3696 size_t total_len = 0;
3699 /* the rule list is NULL terminated, count them first */
3700 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
3701 /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
3702 total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
3704 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
3707 for (i = 0; i < nr_rules; i++) {
3708 assert(offset < total_len);
3709 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
3710 offset += snprintf(scanf_fmts[i], total_len - offset,
3711 ref_rev_parse_rules[i], 2, "%s") + 1;
3715 /* bail out if there are no rules */
3717 return xstrdup(refname);
3719 /* buffer for scanf result, at most refname must fit */
3720 short_name = xstrdup(refname);
3722 /* skip first rule, it will always match */
3723 for (i = nr_rules - 1; i > 0 ; --i) {
3725 int rules_to_fail = i;
3728 if (1 != sscanf(refname, scanf_fmts[i], short_name))
3731 short_name_len = strlen(short_name);
3734 * in strict mode, all (except the matched one) rules
3735 * must fail to resolve to a valid non-ambiguous ref
3738 rules_to_fail = nr_rules;
3741 * check if the short name resolves to a valid ref,
3742 * but use only rules prior to the matched one
3744 for (j = 0; j < rules_to_fail; j++) {
3745 const char *rule = ref_rev_parse_rules[j];
3746 char refname[PATH_MAX];
3748 /* skip matched rule */
3753 * the short name is ambiguous, if it resolves
3754 * (with this previous rule) to a valid ref
3755 * read_ref() returns 0 on success
3757 mksnpath(refname, sizeof(refname),
3758 rule, short_name_len, short_name);
3759 if (ref_exists(refname))
3764 * short name is non-ambiguous if all previous rules
3765 * haven't resolved to a valid ref
3767 if (j == rules_to_fail)
3772 return xstrdup(refname);
3775 static struct string_list *hide_refs;
3777 int parse_hide_refs_config(const char *var, const char *value, const char *section)
3779 if (!strcmp("transfer.hiderefs", var) ||
3780 /* NEEDSWORK: use parse_config_key() once both are merged */
3781 (starts_with(var, section) && var[strlen(section)] == '.' &&
3782 !strcmp(var + strlen(section), ".hiderefs"))) {
3787 return config_error_nonbool(var);
3788 ref = xstrdup(value);
3790 while (len && ref[len - 1] == '/')
3793 hide_refs = xcalloc(1, sizeof(*hide_refs));
3794 hide_refs->strdup_strings = 1;
3796 string_list_append(hide_refs, ref);
3801 int ref_is_hidden(const char *refname)
3803 struct string_list_item *item;
3807 for_each_string_list_item(item, hide_refs) {
3809 if (!starts_with(refname, item->string))
3811 len = strlen(item->string);
3812 if (!refname[len] || refname[len] == '/')