Merge branch 'jk/config-parsing-cleanup'
[git.git] / refs.c
blob29628253087fb0d54a8f7a45938624527f35d4a8
1 #include "cache.h"
2 #include "refs.h"
3 #include "object.h"
4 #include "tag.h"
5 #include "dir.h"
7 /*
8 * Make sure "ref" is something reasonable to have under ".git/refs/";
9 * We do not like it if:
11 * - any path component of it begins with ".", or
12 * - it has double dots "..", or
13 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
14 * - it ends with a "/".
15 * - it ends with ".lock"
16 * - it contains a "\" (backslash)
19 /* Return true iff ch is not allowed in reference names. */
20 static inline int bad_ref_char(int ch)
22 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
23 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
24 return 1;
25 /* 2.13 Pattern Matching Notation */
26 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
27 return 1;
28 return 0;
32 * Try to read one refname component from the front of refname. Return
33 * the length of the component found, or -1 if the component is not
34 * legal.
36 static int check_refname_component(const char *refname, int flags)
38 const char *cp;
39 char last = '\0';
41 for (cp = refname; ; cp++) {
42 char ch = *cp;
43 if (ch == '\0' || ch == '/')
44 break;
45 if (bad_ref_char(ch))
46 return -1; /* Illegal character in refname. */
47 if (last == '.' && ch == '.')
48 return -1; /* Refname contains "..". */
49 if (last == '@' && ch == '{')
50 return -1; /* Refname contains "@{". */
51 last = ch;
53 if (cp == refname)
54 return 0; /* Component has zero length. */
55 if (refname[0] == '.') {
56 if (!(flags & REFNAME_DOT_COMPONENT))
57 return -1; /* Component starts with '.'. */
59 * Even if leading dots are allowed, don't allow "."
60 * as a component (".." is prevented by a rule above).
62 if (refname[1] == '\0')
63 return -1; /* Component equals ".". */
65 if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5))
66 return -1; /* Refname ends with ".lock". */
67 return cp - refname;
70 int check_refname_format(const char *refname, int flags)
72 int component_len, component_count = 0;
74 while (1) {
75 /* We are at the start of a path component. */
76 component_len = check_refname_component(refname, flags);
77 if (component_len <= 0) {
78 if ((flags & REFNAME_REFSPEC_PATTERN) &&
79 refname[0] == '*' &&
80 (refname[1] == '\0' || refname[1] == '/')) {
81 /* Accept one wildcard as a full refname component. */
82 flags &= ~REFNAME_REFSPEC_PATTERN;
83 component_len = 1;
84 } else {
85 return -1;
88 component_count++;
89 if (refname[component_len] == '\0')
90 break;
91 /* Skip to next component. */
92 refname += component_len + 1;
95 if (refname[component_len - 1] == '.')
96 return -1; /* Refname ends with '.'. */
97 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
98 return -1; /* Refname has only one component. */
99 return 0;
102 struct ref_entry;
105 * Information used (along with the information in ref_entry) to
106 * describe a single cached reference. This data structure only
107 * occurs embedded in a union in struct ref_entry, and only when
108 * (ref_entry->flag & REF_DIR) is zero.
110 struct ref_value {
111 unsigned char sha1[20];
112 unsigned char peeled[20];
115 struct ref_cache;
118 * Information used (along with the information in ref_entry) to
119 * describe a level in the hierarchy of references. This data
120 * structure only occurs embedded in a union in struct ref_entry, and
121 * only when (ref_entry.flag & REF_DIR) is set. In that case,
122 * (ref_entry.flag & REF_INCOMPLETE) determines whether the references
123 * in the directory have already been read:
125 * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose
126 * or packed references, already read.
128 * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose
129 * references that hasn't been read yet (nor has any of its
130 * subdirectories).
132 * Entries within a directory are stored within a growable array of
133 * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i <
134 * sorted are sorted by their component name in strcmp() order and the
135 * remaining entries are unsorted.
137 * Loose references are read lazily, one directory at a time. When a
138 * directory of loose references is read, then all of the references
139 * in that directory are stored, and REF_INCOMPLETE stubs are created
140 * for any subdirectories, but the subdirectories themselves are not
141 * read. The reading is triggered by get_ref_dir().
143 struct ref_dir {
144 int nr, alloc;
147 * Entries with index 0 <= i < sorted are sorted by name. New
148 * entries are appended to the list unsorted, and are sorted
149 * only when required; thus we avoid the need to sort the list
150 * after the addition of every reference.
152 int sorted;
154 /* A pointer to the ref_cache that contains this ref_dir. */
155 struct ref_cache *ref_cache;
157 struct ref_entry **entries;
160 /* ISSYMREF=0x01, ISPACKED=0x02, and ISBROKEN=0x04 are public interfaces */
161 #define REF_KNOWS_PEELED 0x08
163 /* ref_entry represents a directory of references */
164 #define REF_DIR 0x10
167 * Entry has not yet been read from disk (used only for REF_DIR
168 * entries representing loose references)
170 #define REF_INCOMPLETE 0x20
173 * A ref_entry represents either a reference or a "subdirectory" of
174 * references.
176 * Each directory in the reference namespace is represented by a
177 * ref_entry with (flags & REF_DIR) set and containing a subdir member
178 * that holds the entries in that directory that have been read so
179 * far. If (flags & REF_INCOMPLETE) is set, then the directory and
180 * its subdirectories haven't been read yet. REF_INCOMPLETE is only
181 * used for loose reference directories.
183 * References are represented by a ref_entry with (flags & REF_DIR)
184 * unset and a value member that describes the reference's value. The
185 * flag member is at the ref_entry level, but it is also needed to
186 * interpret the contents of the value field (in other words, a
187 * ref_value object is not very much use without the enclosing
188 * ref_entry).
190 * Reference names cannot end with slash and directories' names are
191 * always stored with a trailing slash (except for the top-level
192 * directory, which is always denoted by ""). This has two nice
193 * consequences: (1) when the entries in each subdir are sorted
194 * lexicographically by name (as they usually are), the references in
195 * a whole tree can be generated in lexicographic order by traversing
196 * the tree in left-to-right, depth-first order; (2) the names of
197 * references and subdirectories cannot conflict, and therefore the
198 * presence of an empty subdirectory does not block the creation of a
199 * similarly-named reference. (The fact that reference names with the
200 * same leading components can conflict *with each other* is a
201 * separate issue that is regulated by is_refname_available().)
203 * Please note that the name field contains the fully-qualified
204 * reference (or subdirectory) name. Space could be saved by only
205 * storing the relative names. But that would require the full names
206 * to be generated on the fly when iterating in do_for_each_ref(), and
207 * would break callback functions, who have always been able to assume
208 * that the name strings that they are passed will not be freed during
209 * the iteration.
211 struct ref_entry {
212 unsigned char flag; /* ISSYMREF? ISPACKED? */
213 union {
214 struct ref_value value; /* if not (flags&REF_DIR) */
215 struct ref_dir subdir; /* if (flags&REF_DIR) */
216 } u;
218 * The full name of the reference (e.g., "refs/heads/master")
219 * or the full name of the directory with a trailing slash
220 * (e.g., "refs/heads/"):
222 char name[FLEX_ARRAY];
225 static void read_loose_refs(const char *dirname, struct ref_dir *dir);
227 static struct ref_dir *get_ref_dir(struct ref_entry *entry)
229 struct ref_dir *dir;
230 assert(entry->flag & REF_DIR);
231 dir = &entry->u.subdir;
232 if (entry->flag & REF_INCOMPLETE) {
233 read_loose_refs(entry->name, dir);
234 entry->flag &= ~REF_INCOMPLETE;
236 return dir;
239 static struct ref_entry *create_ref_entry(const char *refname,
240 const unsigned char *sha1, int flag,
241 int check_name)
243 int len;
244 struct ref_entry *ref;
246 if (check_name &&
247 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
248 die("Reference has invalid format: '%s'", refname);
249 len = strlen(refname) + 1;
250 ref = xmalloc(sizeof(struct ref_entry) + len);
251 hashcpy(ref->u.value.sha1, sha1);
252 hashclr(ref->u.value.peeled);
253 memcpy(ref->name, refname, len);
254 ref->flag = flag;
255 return ref;
258 static void clear_ref_dir(struct ref_dir *dir);
260 static void free_ref_entry(struct ref_entry *entry)
262 if (entry->flag & REF_DIR) {
264 * Do not use get_ref_dir() here, as that might
265 * trigger the reading of loose refs.
267 clear_ref_dir(&entry->u.subdir);
269 free(entry);
273 * Add a ref_entry to the end of dir (unsorted). Entry is always
274 * stored directly in dir; no recursion into subdirectories is
275 * done.
277 static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry)
279 ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc);
280 dir->entries[dir->nr++] = entry;
281 /* optimize for the case that entries are added in order */
282 if (dir->nr == 1 ||
283 (dir->nr == dir->sorted + 1 &&
284 strcmp(dir->entries[dir->nr - 2]->name,
285 dir->entries[dir->nr - 1]->name) < 0))
286 dir->sorted = dir->nr;
290 * Clear and free all entries in dir, recursively.
292 static void clear_ref_dir(struct ref_dir *dir)
294 int i;
295 for (i = 0; i < dir->nr; i++)
296 free_ref_entry(dir->entries[i]);
297 free(dir->entries);
298 dir->sorted = dir->nr = dir->alloc = 0;
299 dir->entries = NULL;
303 * Create a struct ref_entry object for the specified dirname.
304 * dirname is the name of the directory with a trailing slash (e.g.,
305 * "refs/heads/") or "" for the top-level directory.
307 static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache,
308 const char *dirname, size_t len,
309 int incomplete)
311 struct ref_entry *direntry;
312 direntry = xcalloc(1, sizeof(struct ref_entry) + len + 1);
313 memcpy(direntry->name, dirname, len);
314 direntry->name[len] = '\0';
315 direntry->u.subdir.ref_cache = ref_cache;
316 direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE : 0);
317 return direntry;
320 static int ref_entry_cmp(const void *a, const void *b)
322 struct ref_entry *one = *(struct ref_entry **)a;
323 struct ref_entry *two = *(struct ref_entry **)b;
324 return strcmp(one->name, two->name);
327 static void sort_ref_dir(struct ref_dir *dir);
329 struct string_slice {
330 size_t len;
331 const char *str;
334 static int ref_entry_cmp_sslice(const void *key_, const void *ent_)
336 const struct string_slice *key = key_;
337 const struct ref_entry *ent = *(const struct ref_entry * const *)ent_;
338 int cmp = strncmp(key->str, ent->name, key->len);
339 if (cmp)
340 return cmp;
341 return '\0' - (unsigned char)ent->name[key->len];
345 * Return the entry with the given refname from the ref_dir
346 * (non-recursively), sorting dir if necessary. Return NULL if no
347 * such entry is found. dir must already be complete.
349 static struct ref_entry *search_ref_dir(struct ref_dir *dir,
350 const char *refname, size_t len)
352 struct ref_entry **r;
353 struct string_slice key;
355 if (refname == NULL || !dir->nr)
356 return NULL;
358 sort_ref_dir(dir);
359 key.len = len;
360 key.str = refname;
361 r = bsearch(&key, dir->entries, dir->nr, sizeof(*dir->entries),
362 ref_entry_cmp_sslice);
364 if (r == NULL)
365 return NULL;
367 return *r;
371 * Search for a directory entry directly within dir (without
372 * recursing). Sort dir if necessary. subdirname must be a directory
373 * name (i.e., end in '/'). If mkdir is set, then create the
374 * directory if it is missing; otherwise, return NULL if the desired
375 * directory cannot be found. dir must already be complete.
377 static struct ref_dir *search_for_subdir(struct ref_dir *dir,
378 const char *subdirname, size_t len,
379 int mkdir)
381 struct ref_entry *entry = search_ref_dir(dir, subdirname, len);
382 if (!entry) {
383 if (!mkdir)
384 return NULL;
386 * Since dir is complete, the absence of a subdir
387 * means that the subdir really doesn't exist;
388 * therefore, create an empty record for it but mark
389 * the record complete.
391 entry = create_dir_entry(dir->ref_cache, subdirname, len, 0);
392 add_entry_to_dir(dir, entry);
394 return get_ref_dir(entry);
398 * If refname is a reference name, find the ref_dir within the dir
399 * tree that should hold refname. If refname is a directory name
400 * (i.e., ends in '/'), then return that ref_dir itself. dir must
401 * represent the top-level directory and must already be complete.
402 * Sort ref_dirs and recurse into subdirectories as necessary. If
403 * mkdir is set, then create any missing directories; otherwise,
404 * return NULL if the desired directory cannot be found.
406 static struct ref_dir *find_containing_dir(struct ref_dir *dir,
407 const char *refname, int mkdir)
409 const char *slash;
410 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
411 size_t dirnamelen = slash - refname + 1;
412 struct ref_dir *subdir;
413 subdir = search_for_subdir(dir, refname, dirnamelen, mkdir);
414 if (!subdir) {
415 dir = NULL;
416 break;
418 dir = subdir;
421 return dir;
425 * Find the value entry with the given name in dir, sorting ref_dirs
426 * and recursing into subdirectories as necessary. If the name is not
427 * found or it corresponds to a directory entry, return NULL.
429 static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname)
431 struct ref_entry *entry;
432 dir = find_containing_dir(dir, refname, 0);
433 if (!dir)
434 return NULL;
435 entry = search_ref_dir(dir, refname, strlen(refname));
436 return (entry && !(entry->flag & REF_DIR)) ? entry : NULL;
440 * Add a ref_entry to the ref_dir (unsorted), recursing into
441 * subdirectories as necessary. dir must represent the top-level
442 * directory. Return 0 on success.
444 static int add_ref(struct ref_dir *dir, struct ref_entry *ref)
446 dir = find_containing_dir(dir, ref->name, 1);
447 if (!dir)
448 return -1;
449 add_entry_to_dir(dir, ref);
450 return 0;
454 * Emit a warning and return true iff ref1 and ref2 have the same name
455 * and the same sha1. Die if they have the same name but different
456 * sha1s.
458 static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
460 if (strcmp(ref1->name, ref2->name))
461 return 0;
463 /* Duplicate name; make sure that they don't conflict: */
465 if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR))
466 /* This is impossible by construction */
467 die("Reference directory conflict: %s", ref1->name);
469 if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1))
470 die("Duplicated ref, and SHA1s don't match: %s", ref1->name);
472 warning("Duplicated ref: %s", ref1->name);
473 return 1;
477 * Sort the entries in dir non-recursively (if they are not already
478 * sorted) and remove any duplicate entries.
480 static void sort_ref_dir(struct ref_dir *dir)
482 int i, j;
483 struct ref_entry *last = NULL;
486 * This check also prevents passing a zero-length array to qsort(),
487 * which is a problem on some platforms.
489 if (dir->sorted == dir->nr)
490 return;
492 qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp);
494 /* Remove any duplicates: */
495 for (i = 0, j = 0; j < dir->nr; j++) {
496 struct ref_entry *entry = dir->entries[j];
497 if (last && is_dup_ref(last, entry))
498 free_ref_entry(entry);
499 else
500 last = dir->entries[i++] = entry;
502 dir->sorted = dir->nr = i;
505 #define DO_FOR_EACH_INCLUDE_BROKEN 01
507 static struct ref_entry *current_ref;
509 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
510 int flags, void *cb_data, struct ref_entry *entry)
512 int retval;
513 if (prefixcmp(entry->name, base))
514 return 0;
516 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
517 if (entry->flag & REF_ISBROKEN)
518 return 0; /* ignore broken refs e.g. dangling symref */
519 if (!has_sha1_file(entry->u.value.sha1)) {
520 error("%s does not point to a valid object!", entry->name);
521 return 0;
524 current_ref = entry;
525 retval = fn(entry->name + trim, entry->u.value.sha1, entry->flag, cb_data);
526 current_ref = NULL;
527 return retval;
531 * Call fn for each reference in dir that has index in the range
532 * offset <= index < dir->nr. Recurse into subdirectories that are in
533 * that index range, sorting them before iterating. This function
534 * does not sort dir itself; it should be sorted beforehand.
536 static int do_for_each_ref_in_dir(struct ref_dir *dir, int offset,
537 const char *base,
538 each_ref_fn fn, int trim, int flags, void *cb_data)
540 int i;
541 assert(dir->sorted == dir->nr);
542 for (i = offset; i < dir->nr; i++) {
543 struct ref_entry *entry = dir->entries[i];
544 int retval;
545 if (entry->flag & REF_DIR) {
546 struct ref_dir *subdir = get_ref_dir(entry);
547 sort_ref_dir(subdir);
548 retval = do_for_each_ref_in_dir(subdir, 0,
549 base, fn, trim, flags, cb_data);
550 } else {
551 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
553 if (retval)
554 return retval;
556 return 0;
560 * Call fn for each reference in the union of dir1 and dir2, in order
561 * by refname. Recurse into subdirectories. If a value entry appears
562 * in both dir1 and dir2, then only process the version that is in
563 * dir2. The input dirs must already be sorted, but subdirs will be
564 * sorted as needed.
566 static int do_for_each_ref_in_dirs(struct ref_dir *dir1,
567 struct ref_dir *dir2,
568 const char *base, each_ref_fn fn, int trim,
569 int flags, void *cb_data)
571 int retval;
572 int i1 = 0, i2 = 0;
574 assert(dir1->sorted == dir1->nr);
575 assert(dir2->sorted == dir2->nr);
576 while (1) {
577 struct ref_entry *e1, *e2;
578 int cmp;
579 if (i1 == dir1->nr) {
580 return do_for_each_ref_in_dir(dir2, i2,
581 base, fn, trim, flags, cb_data);
583 if (i2 == dir2->nr) {
584 return do_for_each_ref_in_dir(dir1, i1,
585 base, fn, trim, flags, cb_data);
587 e1 = dir1->entries[i1];
588 e2 = dir2->entries[i2];
589 cmp = strcmp(e1->name, e2->name);
590 if (cmp == 0) {
591 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) {
592 /* Both are directories; descend them in parallel. */
593 struct ref_dir *subdir1 = get_ref_dir(e1);
594 struct ref_dir *subdir2 = get_ref_dir(e2);
595 sort_ref_dir(subdir1);
596 sort_ref_dir(subdir2);
597 retval = do_for_each_ref_in_dirs(
598 subdir1, subdir2,
599 base, fn, trim, flags, cb_data);
600 i1++;
601 i2++;
602 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) {
603 /* Both are references; ignore the one from dir1. */
604 retval = do_one_ref(base, fn, trim, flags, cb_data, e2);
605 i1++;
606 i2++;
607 } else {
608 die("conflict between reference and directory: %s",
609 e1->name);
611 } else {
612 struct ref_entry *e;
613 if (cmp < 0) {
614 e = e1;
615 i1++;
616 } else {
617 e = e2;
618 i2++;
620 if (e->flag & REF_DIR) {
621 struct ref_dir *subdir = get_ref_dir(e);
622 sort_ref_dir(subdir);
623 retval = do_for_each_ref_in_dir(
624 subdir, 0,
625 base, fn, trim, flags, cb_data);
626 } else {
627 retval = do_one_ref(base, fn, trim, flags, cb_data, e);
630 if (retval)
631 return retval;
633 if (i1 < dir1->nr)
634 return do_for_each_ref_in_dir(dir1, i1,
635 base, fn, trim, flags, cb_data);
636 if (i2 < dir2->nr)
637 return do_for_each_ref_in_dir(dir2, i2,
638 base, fn, trim, flags, cb_data);
639 return 0;
643 * Return true iff refname1 and refname2 conflict with each other.
644 * Two reference names conflict if one of them exactly matches the
645 * leading components of the other; e.g., "foo/bar" conflicts with
646 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
647 * "foo/barbados".
649 static int names_conflict(const char *refname1, const char *refname2)
651 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
653 return (*refname1 == '\0' && *refname2 == '/')
654 || (*refname1 == '/' && *refname2 == '\0');
657 struct name_conflict_cb {
658 const char *refname;
659 const char *oldrefname;
660 const char *conflicting_refname;
663 static int name_conflict_fn(const char *existingrefname, const unsigned char *sha1,
664 int flags, void *cb_data)
666 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
667 if (data->oldrefname && !strcmp(data->oldrefname, existingrefname))
668 return 0;
669 if (names_conflict(data->refname, existingrefname)) {
670 data->conflicting_refname = existingrefname;
671 return 1;
673 return 0;
677 * Return true iff a reference named refname could be created without
678 * conflicting with the name of an existing reference in array. If
679 * oldrefname is non-NULL, ignore potential conflicts with oldrefname
680 * (e.g., because oldrefname is scheduled for deletion in the same
681 * operation).
683 static int is_refname_available(const char *refname, const char *oldrefname,
684 struct ref_dir *dir)
686 struct name_conflict_cb data;
687 data.refname = refname;
688 data.oldrefname = oldrefname;
689 data.conflicting_refname = NULL;
691 sort_ref_dir(dir);
692 if (do_for_each_ref_in_dir(dir, 0, "", name_conflict_fn,
693 0, DO_FOR_EACH_INCLUDE_BROKEN,
694 &data)) {
695 error("'%s' exists; cannot create '%s'",
696 data.conflicting_refname, refname);
697 return 0;
699 return 1;
703 * Future: need to be in "struct repository"
704 * when doing a full libification.
706 static struct ref_cache {
707 struct ref_cache *next;
708 struct ref_entry *loose;
709 struct ref_entry *packed;
710 /* The submodule name, or "" for the main repo. */
711 char name[FLEX_ARRAY];
712 } *ref_cache;
714 static void clear_packed_ref_cache(struct ref_cache *refs)
716 if (refs->packed) {
717 free_ref_entry(refs->packed);
718 refs->packed = NULL;
722 static void clear_loose_ref_cache(struct ref_cache *refs)
724 if (refs->loose) {
725 free_ref_entry(refs->loose);
726 refs->loose = NULL;
730 static struct ref_cache *create_ref_cache(const char *submodule)
732 int len;
733 struct ref_cache *refs;
734 if (!submodule)
735 submodule = "";
736 len = strlen(submodule) + 1;
737 refs = xcalloc(1, sizeof(struct ref_cache) + len);
738 memcpy(refs->name, submodule, len);
739 return refs;
743 * Return a pointer to a ref_cache for the specified submodule. For
744 * the main repository, use submodule==NULL. The returned structure
745 * will be allocated and initialized but not necessarily populated; it
746 * should not be freed.
748 static struct ref_cache *get_ref_cache(const char *submodule)
750 struct ref_cache *refs = ref_cache;
751 if (!submodule)
752 submodule = "";
753 while (refs) {
754 if (!strcmp(submodule, refs->name))
755 return refs;
756 refs = refs->next;
759 refs = create_ref_cache(submodule);
760 refs->next = ref_cache;
761 ref_cache = refs;
762 return refs;
765 void invalidate_ref_cache(const char *submodule)
767 struct ref_cache *refs = get_ref_cache(submodule);
768 clear_packed_ref_cache(refs);
769 clear_loose_ref_cache(refs);
773 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
774 * Return a pointer to the refname within the line (null-terminated),
775 * or NULL if there was a problem.
777 static const char *parse_ref_line(char *line, unsigned char *sha1)
780 * 42: the answer to everything.
782 * In this case, it happens to be the answer to
783 * 40 (length of sha1 hex representation)
784 * +1 (space in between hex and name)
785 * +1 (newline at the end of the line)
787 int len = strlen(line) - 42;
789 if (len <= 0)
790 return NULL;
791 if (get_sha1_hex(line, sha1) < 0)
792 return NULL;
793 if (!isspace(line[40]))
794 return NULL;
795 line += 41;
796 if (isspace(*line))
797 return NULL;
798 if (line[len] != '\n')
799 return NULL;
800 line[len] = 0;
802 return line;
805 static void read_packed_refs(FILE *f, struct ref_dir *dir)
807 struct ref_entry *last = NULL;
808 char refline[PATH_MAX];
809 int flag = REF_ISPACKED;
811 while (fgets(refline, sizeof(refline), f)) {
812 unsigned char sha1[20];
813 const char *refname;
814 static const char header[] = "# pack-refs with:";
816 if (!strncmp(refline, header, sizeof(header)-1)) {
817 const char *traits = refline + sizeof(header) - 1;
818 if (strstr(traits, " peeled "))
819 flag |= REF_KNOWS_PEELED;
820 /* perhaps other traits later as well */
821 continue;
824 refname = parse_ref_line(refline, sha1);
825 if (refname) {
826 last = create_ref_entry(refname, sha1, flag, 1);
827 add_ref(dir, last);
828 continue;
830 if (last &&
831 refline[0] == '^' &&
832 strlen(refline) == 42 &&
833 refline[41] == '\n' &&
834 !get_sha1_hex(refline + 1, sha1))
835 hashcpy(last->u.value.peeled, sha1);
839 static struct ref_dir *get_packed_refs(struct ref_cache *refs)
841 if (!refs->packed) {
842 const char *packed_refs_file;
843 FILE *f;
845 refs->packed = create_dir_entry(refs, "", 0, 0);
846 if (*refs->name)
847 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
848 else
849 packed_refs_file = git_path("packed-refs");
850 f = fopen(packed_refs_file, "r");
851 if (f) {
852 read_packed_refs(f, get_ref_dir(refs->packed));
853 fclose(f);
856 return get_ref_dir(refs->packed);
859 void add_packed_ref(const char *refname, const unsigned char *sha1)
861 add_ref(get_packed_refs(get_ref_cache(NULL)),
862 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
866 * Read the loose references from the namespace dirname into dir
867 * (without recursing). dirname must end with '/'. dir must be the
868 * directory entry corresponding to dirname.
870 static void read_loose_refs(const char *dirname, struct ref_dir *dir)
872 struct ref_cache *refs = dir->ref_cache;
873 DIR *d;
874 const char *path;
875 struct dirent *de;
876 int dirnamelen = strlen(dirname);
877 struct strbuf refname;
879 if (*refs->name)
880 path = git_path_submodule(refs->name, "%s", dirname);
881 else
882 path = git_path("%s", dirname);
884 d = opendir(path);
885 if (!d)
886 return;
888 strbuf_init(&refname, dirnamelen + 257);
889 strbuf_add(&refname, dirname, dirnamelen);
891 while ((de = readdir(d)) != NULL) {
892 unsigned char sha1[20];
893 struct stat st;
894 int flag;
895 const char *refdir;
897 if (de->d_name[0] == '.')
898 continue;
899 if (has_extension(de->d_name, ".lock"))
900 continue;
901 strbuf_addstr(&refname, de->d_name);
902 refdir = *refs->name
903 ? git_path_submodule(refs->name, "%s", refname.buf)
904 : git_path("%s", refname.buf);
905 if (stat(refdir, &st) < 0) {
906 ; /* silently ignore */
907 } else if (S_ISDIR(st.st_mode)) {
908 strbuf_addch(&refname, '/');
909 add_entry_to_dir(dir,
910 create_dir_entry(refs, refname.buf,
911 refname.len, 1));
912 } else {
913 if (*refs->name) {
914 hashclr(sha1);
915 flag = 0;
916 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {
917 hashclr(sha1);
918 flag |= REF_ISBROKEN;
920 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {
921 hashclr(sha1);
922 flag |= REF_ISBROKEN;
924 add_entry_to_dir(dir,
925 create_ref_entry(refname.buf, sha1, flag, 1));
927 strbuf_setlen(&refname, dirnamelen);
929 strbuf_release(&refname);
930 closedir(d);
933 static struct ref_dir *get_loose_refs(struct ref_cache *refs)
935 if (!refs->loose) {
937 * Mark the top-level directory complete because we
938 * are about to read the only subdirectory that can
939 * hold references:
941 refs->loose = create_dir_entry(refs, "", 0, 0);
943 * Create an incomplete entry for "refs/":
945 add_entry_to_dir(get_ref_dir(refs->loose),
946 create_dir_entry(refs, "refs/", 5, 1));
948 return get_ref_dir(refs->loose);
951 /* We allow "recursive" symbolic refs. Only within reason, though */
952 #define MAXDEPTH 5
953 #define MAXREFLEN (1024)
956 * Called by resolve_gitlink_ref_recursive() after it failed to read
957 * from the loose refs in ref_cache refs. Find <refname> in the
958 * packed-refs file for the submodule.
960 static int resolve_gitlink_packed_ref(struct ref_cache *refs,
961 const char *refname, unsigned char *sha1)
963 struct ref_entry *ref;
964 struct ref_dir *dir = get_packed_refs(refs);
966 ref = find_ref(dir, refname);
967 if (ref == NULL)
968 return -1;
970 memcpy(sha1, ref->u.value.sha1, 20);
971 return 0;
974 static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
975 const char *refname, unsigned char *sha1,
976 int recursion)
978 int fd, len;
979 char buffer[128], *p;
980 char *path;
982 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
983 return -1;
984 path = *refs->name
985 ? git_path_submodule(refs->name, "%s", refname)
986 : git_path("%s", refname);
987 fd = open(path, O_RDONLY);
988 if (fd < 0)
989 return resolve_gitlink_packed_ref(refs, refname, sha1);
991 len = read(fd, buffer, sizeof(buffer)-1);
992 close(fd);
993 if (len < 0)
994 return -1;
995 while (len && isspace(buffer[len-1]))
996 len--;
997 buffer[len] = 0;
999 /* Was it a detached head or an old-fashioned symlink? */
1000 if (!get_sha1_hex(buffer, sha1))
1001 return 0;
1003 /* Symref? */
1004 if (strncmp(buffer, "ref:", 4))
1005 return -1;
1006 p = buffer + 4;
1007 while (isspace(*p))
1008 p++;
1010 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
1013 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
1015 int len = strlen(path), retval;
1016 char *submodule;
1017 struct ref_cache *refs;
1019 while (len && path[len-1] == '/')
1020 len--;
1021 if (!len)
1022 return -1;
1023 submodule = xstrndup(path, len);
1024 refs = get_ref_cache(submodule);
1025 free(submodule);
1027 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
1028 return retval;
1032 * Try to read ref from the packed references. On success, set sha1
1033 * and return 0; otherwise, return -1.
1035 static int get_packed_ref(const char *refname, unsigned char *sha1)
1037 struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
1038 struct ref_entry *entry = find_ref(packed, refname);
1039 if (entry) {
1040 hashcpy(sha1, entry->u.value.sha1);
1041 return 0;
1043 return -1;
1046 const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
1048 int depth = MAXDEPTH;
1049 ssize_t len;
1050 char buffer[256];
1051 static char refname_buffer[256];
1053 if (flag)
1054 *flag = 0;
1056 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
1057 return NULL;
1059 for (;;) {
1060 char path[PATH_MAX];
1061 struct stat st;
1062 char *buf;
1063 int fd;
1065 if (--depth < 0)
1066 return NULL;
1068 git_snpath(path, sizeof(path), "%s", refname);
1070 if (lstat(path, &st) < 0) {
1071 if (errno != ENOENT)
1072 return NULL;
1074 * The loose reference file does not exist;
1075 * check for a packed reference.
1077 if (!get_packed_ref(refname, sha1)) {
1078 if (flag)
1079 *flag |= REF_ISPACKED;
1080 return refname;
1082 /* The reference is not a packed reference, either. */
1083 if (reading) {
1084 return NULL;
1085 } else {
1086 hashclr(sha1);
1087 return refname;
1091 /* Follow "normalized" - ie "refs/.." symlinks by hand */
1092 if (S_ISLNK(st.st_mode)) {
1093 len = readlink(path, buffer, sizeof(buffer)-1);
1094 if (len < 0)
1095 return NULL;
1096 buffer[len] = 0;
1097 if (!prefixcmp(buffer, "refs/") &&
1098 !check_refname_format(buffer, 0)) {
1099 strcpy(refname_buffer, buffer);
1100 refname = refname_buffer;
1101 if (flag)
1102 *flag |= REF_ISSYMREF;
1103 continue;
1107 /* Is it a directory? */
1108 if (S_ISDIR(st.st_mode)) {
1109 errno = EISDIR;
1110 return NULL;
1114 * Anything else, just open it and try to use it as
1115 * a ref
1117 fd = open(path, O_RDONLY);
1118 if (fd < 0)
1119 return NULL;
1120 len = read_in_full(fd, buffer, sizeof(buffer)-1);
1121 close(fd);
1122 if (len < 0)
1123 return NULL;
1124 while (len && isspace(buffer[len-1]))
1125 len--;
1126 buffer[len] = '\0';
1129 * Is it a symbolic ref?
1131 if (prefixcmp(buffer, "ref:"))
1132 break;
1133 if (flag)
1134 *flag |= REF_ISSYMREF;
1135 buf = buffer + 4;
1136 while (isspace(*buf))
1137 buf++;
1138 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
1139 if (flag)
1140 *flag |= REF_ISBROKEN;
1141 return NULL;
1143 refname = strcpy(refname_buffer, buf);
1145 /* Please note that FETCH_HEAD has a second line containing other data. */
1146 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
1147 if (flag)
1148 *flag |= REF_ISBROKEN;
1149 return NULL;
1151 return refname;
1154 char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
1156 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
1157 return ret ? xstrdup(ret) : NULL;
1160 /* The argument to filter_refs */
1161 struct ref_filter {
1162 const char *pattern;
1163 each_ref_fn *fn;
1164 void *cb_data;
1167 int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
1169 if (resolve_ref_unsafe(refname, sha1, reading, flags))
1170 return 0;
1171 return -1;
1174 int read_ref(const char *refname, unsigned char *sha1)
1176 return read_ref_full(refname, sha1, 1, NULL);
1179 int ref_exists(const char *refname)
1181 unsigned char sha1[20];
1182 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
1185 static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
1186 void *data)
1188 struct ref_filter *filter = (struct ref_filter *)data;
1189 if (fnmatch(filter->pattern, refname, 0))
1190 return 0;
1191 return filter->fn(refname, sha1, flags, filter->cb_data);
1194 int peel_ref(const char *refname, unsigned char *sha1)
1196 int flag;
1197 unsigned char base[20];
1198 struct object *o;
1200 if (current_ref && (current_ref->name == refname
1201 || !strcmp(current_ref->name, refname))) {
1202 if (current_ref->flag & REF_KNOWS_PEELED) {
1203 if (is_null_sha1(current_ref->u.value.peeled))
1204 return -1;
1205 hashcpy(sha1, current_ref->u.value.peeled);
1206 return 0;
1208 hashcpy(base, current_ref->u.value.sha1);
1209 goto fallback;
1212 if (read_ref_full(refname, base, 1, &flag))
1213 return -1;
1215 if ((flag & REF_ISPACKED)) {
1216 struct ref_dir *dir = get_packed_refs(get_ref_cache(NULL));
1217 struct ref_entry *r = find_ref(dir, refname);
1219 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
1220 hashcpy(sha1, r->u.value.peeled);
1221 return 0;
1225 fallback:
1226 o = lookup_unknown_object(base);
1227 if (o->type == OBJ_NONE) {
1228 int type = sha1_object_info(base, NULL);
1229 if (type < 0)
1230 return -1;
1231 o->type = type;
1234 if (o->type == OBJ_TAG) {
1235 o = deref_tag_noverify(o);
1236 if (o) {
1237 hashcpy(sha1, o->sha1);
1238 return 0;
1241 return -1;
1244 struct warn_if_dangling_data {
1245 FILE *fp;
1246 const char *refname;
1247 const char *msg_fmt;
1250 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
1251 int flags, void *cb_data)
1253 struct warn_if_dangling_data *d = cb_data;
1254 const char *resolves_to;
1255 unsigned char junk[20];
1257 if (!(flags & REF_ISSYMREF))
1258 return 0;
1260 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
1261 if (!resolves_to || strcmp(resolves_to, d->refname))
1262 return 0;
1264 fprintf(d->fp, d->msg_fmt, refname);
1265 fputc('\n', d->fp);
1266 return 0;
1269 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
1271 struct warn_if_dangling_data data;
1273 data.fp = fp;
1274 data.refname = refname;
1275 data.msg_fmt = msg_fmt;
1276 for_each_rawref(warn_if_dangling_symref, &data);
1279 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
1280 int trim, int flags, void *cb_data)
1282 struct ref_cache *refs = get_ref_cache(submodule);
1283 struct ref_dir *packed_dir = get_packed_refs(refs);
1284 struct ref_dir *loose_dir = get_loose_refs(refs);
1285 int retval = 0;
1287 if (base && *base) {
1288 packed_dir = find_containing_dir(packed_dir, base, 0);
1289 loose_dir = find_containing_dir(loose_dir, base, 0);
1292 if (packed_dir && loose_dir) {
1293 sort_ref_dir(packed_dir);
1294 sort_ref_dir(loose_dir);
1295 retval = do_for_each_ref_in_dirs(
1296 packed_dir, loose_dir,
1297 base, fn, trim, flags, cb_data);
1298 } else if (packed_dir) {
1299 sort_ref_dir(packed_dir);
1300 retval = do_for_each_ref_in_dir(
1301 packed_dir, 0,
1302 base, fn, trim, flags, cb_data);
1303 } else if (loose_dir) {
1304 sort_ref_dir(loose_dir);
1305 retval = do_for_each_ref_in_dir(
1306 loose_dir, 0,
1307 base, fn, trim, flags, cb_data);
1310 return retval;
1313 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
1315 unsigned char sha1[20];
1316 int flag;
1318 if (submodule) {
1319 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
1320 return fn("HEAD", sha1, 0, cb_data);
1322 return 0;
1325 if (!read_ref_full("HEAD", sha1, 1, &flag))
1326 return fn("HEAD", sha1, flag, cb_data);
1328 return 0;
1331 int head_ref(each_ref_fn fn, void *cb_data)
1333 return do_head_ref(NULL, fn, cb_data);
1336 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1338 return do_head_ref(submodule, fn, cb_data);
1341 int for_each_ref(each_ref_fn fn, void *cb_data)
1343 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
1346 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1348 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
1351 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1353 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
1356 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1357 each_ref_fn fn, void *cb_data)
1359 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
1362 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
1364 return for_each_ref_in("refs/tags/", fn, cb_data);
1367 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1369 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1372 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
1374 return for_each_ref_in("refs/heads/", fn, cb_data);
1377 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1379 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1382 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
1384 return for_each_ref_in("refs/remotes/", fn, cb_data);
1387 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1389 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1392 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1394 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
1397 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1399 struct strbuf buf = STRBUF_INIT;
1400 int ret = 0;
1401 unsigned char sha1[20];
1402 int flag;
1404 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
1405 if (!read_ref_full(buf.buf, sha1, 1, &flag))
1406 ret = fn(buf.buf, sha1, flag, cb_data);
1407 strbuf_release(&buf);
1409 return ret;
1412 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1414 struct strbuf buf = STRBUF_INIT;
1415 int ret;
1416 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1417 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
1418 strbuf_release(&buf);
1419 return ret;
1422 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1423 const char *prefix, void *cb_data)
1425 struct strbuf real_pattern = STRBUF_INIT;
1426 struct ref_filter filter;
1427 int ret;
1429 if (!prefix && prefixcmp(pattern, "refs/"))
1430 strbuf_addstr(&real_pattern, "refs/");
1431 else if (prefix)
1432 strbuf_addstr(&real_pattern, prefix);
1433 strbuf_addstr(&real_pattern, pattern);
1435 if (!has_glob_specials(pattern)) {
1436 /* Append implied '/' '*' if not present. */
1437 if (real_pattern.buf[real_pattern.len - 1] != '/')
1438 strbuf_addch(&real_pattern, '/');
1439 /* No need to check for '*', there is none. */
1440 strbuf_addch(&real_pattern, '*');
1443 filter.pattern = real_pattern.buf;
1444 filter.fn = fn;
1445 filter.cb_data = cb_data;
1446 ret = for_each_ref(filter_refs, &filter);
1448 strbuf_release(&real_pattern);
1449 return ret;
1452 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1454 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1457 int for_each_rawref(each_ref_fn fn, void *cb_data)
1459 return do_for_each_ref(NULL, "", fn, 0,
1460 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1463 const char *prettify_refname(const char *name)
1465 return name + (
1466 !prefixcmp(name, "refs/heads/") ? 11 :
1467 !prefixcmp(name, "refs/tags/") ? 10 :
1468 !prefixcmp(name, "refs/remotes/") ? 13 :
1472 const char *ref_rev_parse_rules[] = {
1473 "%.*s",
1474 "refs/%.*s",
1475 "refs/tags/%.*s",
1476 "refs/heads/%.*s",
1477 "refs/remotes/%.*s",
1478 "refs/remotes/%.*s/HEAD",
1479 NULL
1482 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1484 const char **p;
1485 const int abbrev_name_len = strlen(abbrev_name);
1487 for (p = rules; *p; p++) {
1488 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1489 return 1;
1493 return 0;
1496 static struct ref_lock *verify_lock(struct ref_lock *lock,
1497 const unsigned char *old_sha1, int mustexist)
1499 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
1500 error("Can't verify ref %s", lock->ref_name);
1501 unlock_ref(lock);
1502 return NULL;
1504 if (hashcmp(lock->old_sha1, old_sha1)) {
1505 error("Ref %s is at %s but expected %s", lock->ref_name,
1506 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1507 unlock_ref(lock);
1508 return NULL;
1510 return lock;
1513 static int remove_empty_directories(const char *file)
1515 /* we want to create a file but there is a directory there;
1516 * if that is an empty directory (or a directory that contains
1517 * only empty directories), remove them.
1519 struct strbuf path;
1520 int result;
1522 strbuf_init(&path, 20);
1523 strbuf_addstr(&path, file);
1525 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1527 strbuf_release(&path);
1529 return result;
1533 * *string and *len will only be substituted, and *string returned (for
1534 * later free()ing) if the string passed in is a magic short-hand form
1535 * to name a branch.
1537 static char *substitute_branch_name(const char **string, int *len)
1539 struct strbuf buf = STRBUF_INIT;
1540 int ret = interpret_branch_name(*string, &buf);
1542 if (ret == *len) {
1543 size_t size;
1544 *string = strbuf_detach(&buf, &size);
1545 *len = size;
1546 return (char *)*string;
1549 return NULL;
1552 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1554 char *last_branch = substitute_branch_name(&str, &len);
1555 const char **p, *r;
1556 int refs_found = 0;
1558 *ref = NULL;
1559 for (p = ref_rev_parse_rules; *p; p++) {
1560 char fullref[PATH_MAX];
1561 unsigned char sha1_from_ref[20];
1562 unsigned char *this_result;
1563 int flag;
1565 this_result = refs_found ? sha1_from_ref : sha1;
1566 mksnpath(fullref, sizeof(fullref), *p, len, str);
1567 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
1568 if (r) {
1569 if (!refs_found++)
1570 *ref = xstrdup(r);
1571 if (!warn_ambiguous_refs)
1572 break;
1573 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
1574 warning("ignoring dangling symref %s.", fullref);
1575 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1576 warning("ignoring broken ref %s.", fullref);
1579 free(last_branch);
1580 return refs_found;
1583 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1585 char *last_branch = substitute_branch_name(&str, &len);
1586 const char **p;
1587 int logs_found = 0;
1589 *log = NULL;
1590 for (p = ref_rev_parse_rules; *p; p++) {
1591 struct stat st;
1592 unsigned char hash[20];
1593 char path[PATH_MAX];
1594 const char *ref, *it;
1596 mksnpath(path, sizeof(path), *p, len, str);
1597 ref = resolve_ref_unsafe(path, hash, 1, NULL);
1598 if (!ref)
1599 continue;
1600 if (!stat(git_path("logs/%s", path), &st) &&
1601 S_ISREG(st.st_mode))
1602 it = path;
1603 else if (strcmp(ref, path) &&
1604 !stat(git_path("logs/%s", ref), &st) &&
1605 S_ISREG(st.st_mode))
1606 it = ref;
1607 else
1608 continue;
1609 if (!logs_found++) {
1610 *log = xstrdup(it);
1611 hashcpy(sha1, hash);
1613 if (!warn_ambiguous_refs)
1614 break;
1616 free(last_branch);
1617 return logs_found;
1620 static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1621 const unsigned char *old_sha1,
1622 int flags, int *type_p)
1624 char *ref_file;
1625 const char *orig_refname = refname;
1626 struct ref_lock *lock;
1627 int last_errno = 0;
1628 int type, lflags;
1629 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1630 int missing = 0;
1632 lock = xcalloc(1, sizeof(struct ref_lock));
1633 lock->lock_fd = -1;
1635 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
1636 if (!refname && errno == EISDIR) {
1637 /* we are trying to lock foo but we used to
1638 * have foo/bar which now does not exist;
1639 * it is normal for the empty directory 'foo'
1640 * to remain.
1642 ref_file = git_path("%s", orig_refname);
1643 if (remove_empty_directories(ref_file)) {
1644 last_errno = errno;
1645 error("there are still refs under '%s'", orig_refname);
1646 goto error_return;
1648 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
1650 if (type_p)
1651 *type_p = type;
1652 if (!refname) {
1653 last_errno = errno;
1654 error("unable to resolve reference %s: %s",
1655 orig_refname, strerror(errno));
1656 goto error_return;
1658 missing = is_null_sha1(lock->old_sha1);
1659 /* When the ref did not exist and we are creating it,
1660 * make sure there is no existing ref that is packed
1661 * whose name begins with our refname, nor a ref whose
1662 * name is a proper prefix of our refname.
1664 if (missing &&
1665 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
1666 last_errno = ENOTDIR;
1667 goto error_return;
1670 lock->lk = xcalloc(1, sizeof(struct lock_file));
1672 lflags = LOCK_DIE_ON_ERROR;
1673 if (flags & REF_NODEREF) {
1674 refname = orig_refname;
1675 lflags |= LOCK_NODEREF;
1677 lock->ref_name = xstrdup(refname);
1678 lock->orig_ref_name = xstrdup(orig_refname);
1679 ref_file = git_path("%s", refname);
1680 if (missing)
1681 lock->force_write = 1;
1682 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1683 lock->force_write = 1;
1685 if (safe_create_leading_directories(ref_file)) {
1686 last_errno = errno;
1687 error("unable to create directory for %s", ref_file);
1688 goto error_return;
1691 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1692 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1694 error_return:
1695 unlock_ref(lock);
1696 errno = last_errno;
1697 return NULL;
1700 struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
1702 char refpath[PATH_MAX];
1703 if (check_refname_format(refname, 0))
1704 return NULL;
1705 strcpy(refpath, mkpath("refs/%s", refname));
1706 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1709 struct ref_lock *lock_any_ref_for_update(const char *refname,
1710 const unsigned char *old_sha1, int flags)
1712 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
1713 return NULL;
1714 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
1717 struct repack_without_ref_sb {
1718 const char *refname;
1719 int fd;
1722 static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,
1723 int flags, void *cb_data)
1725 struct repack_without_ref_sb *data = cb_data;
1726 char line[PATH_MAX + 100];
1727 int len;
1729 if (!strcmp(data->refname, refname))
1730 return 0;
1731 len = snprintf(line, sizeof(line), "%s %s\n",
1732 sha1_to_hex(sha1), refname);
1733 /* this should not happen but just being defensive */
1734 if (len > sizeof(line))
1735 die("too long a refname '%s'", refname);
1736 write_or_die(data->fd, line, len);
1737 return 0;
1740 static struct lock_file packlock;
1742 static int repack_without_ref(const char *refname)
1744 struct repack_without_ref_sb data;
1745 struct ref_cache *refs = get_ref_cache(NULL);
1746 struct ref_dir *packed = get_packed_refs(refs);
1747 if (find_ref(packed, refname) == NULL)
1748 return 0;
1749 data.refname = refname;
1750 data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1751 if (data.fd < 0) {
1752 unable_to_lock_error(git_path("packed-refs"), errno);
1753 return error("cannot delete '%s' from packed refs", refname);
1755 clear_packed_ref_cache(refs);
1756 packed = get_packed_refs(refs);
1757 do_for_each_ref_in_dir(packed, 0, "", repack_without_ref_fn, 0, 0, &data);
1758 return commit_lock_file(&packlock);
1761 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1763 struct ref_lock *lock;
1764 int err, i = 0, ret = 0, flag = 0;
1766 lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);
1767 if (!lock)
1768 return 1;
1769 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1770 /* loose */
1771 i = strlen(lock->lk->filename) - 5; /* .lock */
1772 lock->lk->filename[i] = 0;
1773 err = unlink_or_warn(lock->lk->filename);
1774 if (err && errno != ENOENT)
1775 ret = 1;
1777 lock->lk->filename[i] = '.';
1779 /* removing the loose one could have resurrected an earlier
1780 * packed one. Also, if it was not loose we need to repack
1781 * without it.
1783 ret |= repack_without_ref(lock->ref_name);
1785 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1786 invalidate_ref_cache(NULL);
1787 unlock_ref(lock);
1788 return ret;
1792 * People using contrib's git-new-workdir have .git/logs/refs ->
1793 * /some/other/path/.git/logs/refs, and that may live on another device.
1795 * IOW, to avoid cross device rename errors, the temporary renamed log must
1796 * live into logs/refs.
1798 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1800 int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
1802 unsigned char sha1[20], orig_sha1[20];
1803 int flag = 0, logmoved = 0;
1804 struct ref_lock *lock;
1805 struct stat loginfo;
1806 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
1807 const char *symref = NULL;
1808 struct ref_cache *refs = get_ref_cache(NULL);
1810 if (log && S_ISLNK(loginfo.st_mode))
1811 return error("reflog for %s is a symlink", oldrefname);
1813 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
1814 if (flag & REF_ISSYMREF)
1815 return error("refname %s is a symbolic ref, renaming it is not supported",
1816 oldrefname);
1817 if (!symref)
1818 return error("refname %s not found", oldrefname);
1820 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
1821 return 1;
1823 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
1824 return 1;
1826 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
1827 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1828 oldrefname, strerror(errno));
1830 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
1831 error("unable to delete old %s", oldrefname);
1832 goto rollback;
1835 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
1836 delete_ref(newrefname, sha1, REF_NODEREF)) {
1837 if (errno==EISDIR) {
1838 if (remove_empty_directories(git_path("%s", newrefname))) {
1839 error("Directory not empty: %s", newrefname);
1840 goto rollback;
1842 } else {
1843 error("unable to delete existing %s", newrefname);
1844 goto rollback;
1848 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1849 error("unable to create directory for %s", newrefname);
1850 goto rollback;
1853 retry:
1854 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
1855 if (errno==EISDIR || errno==ENOTDIR) {
1857 * rename(a, b) when b is an existing
1858 * directory ought to result in ISDIR, but
1859 * Solaris 5.8 gives ENOTDIR. Sheesh.
1861 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1862 error("Directory not empty: logs/%s", newrefname);
1863 goto rollback;
1865 goto retry;
1866 } else {
1867 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1868 newrefname, strerror(errno));
1869 goto rollback;
1872 logmoved = log;
1874 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
1875 if (!lock) {
1876 error("unable to lock %s for update", newrefname);
1877 goto rollback;
1879 lock->force_write = 1;
1880 hashcpy(lock->old_sha1, orig_sha1);
1881 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1882 error("unable to write current sha1 into %s", newrefname);
1883 goto rollback;
1886 return 0;
1888 rollback:
1889 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
1890 if (!lock) {
1891 error("unable to lock %s for rollback", oldrefname);
1892 goto rollbacklog;
1895 lock->force_write = 1;
1896 flag = log_all_ref_updates;
1897 log_all_ref_updates = 0;
1898 if (write_ref_sha1(lock, orig_sha1, NULL))
1899 error("unable to write current sha1 into %s", oldrefname);
1900 log_all_ref_updates = flag;
1902 rollbacklog:
1903 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
1904 error("unable to restore logfile %s from %s: %s",
1905 oldrefname, newrefname, strerror(errno));
1906 if (!logmoved && log &&
1907 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
1908 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1909 oldrefname, strerror(errno));
1911 return 1;
1914 int close_ref(struct ref_lock *lock)
1916 if (close_lock_file(lock->lk))
1917 return -1;
1918 lock->lock_fd = -1;
1919 return 0;
1922 int commit_ref(struct ref_lock *lock)
1924 if (commit_lock_file(lock->lk))
1925 return -1;
1926 lock->lock_fd = -1;
1927 return 0;
1930 void unlock_ref(struct ref_lock *lock)
1932 /* Do not free lock->lk -- atexit() still looks at them */
1933 if (lock->lk)
1934 rollback_lock_file(lock->lk);
1935 free(lock->ref_name);
1936 free(lock->orig_ref_name);
1937 free(lock);
1941 * copy the reflog message msg to buf, which has been allocated sufficiently
1942 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1943 * because reflog file is one line per entry.
1945 static int copy_msg(char *buf, const char *msg)
1947 char *cp = buf;
1948 char c;
1949 int wasspace = 1;
1951 *cp++ = '\t';
1952 while ((c = *msg++)) {
1953 if (wasspace && isspace(c))
1954 continue;
1955 wasspace = isspace(c);
1956 if (wasspace)
1957 c = ' ';
1958 *cp++ = c;
1960 while (buf < cp && isspace(cp[-1]))
1961 cp--;
1962 *cp++ = '\n';
1963 return cp - buf;
1966 int log_ref_setup(const char *refname, char *logfile, int bufsize)
1968 int logfd, oflags = O_APPEND | O_WRONLY;
1970 git_snpath(logfile, bufsize, "logs/%s", refname);
1971 if (log_all_ref_updates &&
1972 (!prefixcmp(refname, "refs/heads/") ||
1973 !prefixcmp(refname, "refs/remotes/") ||
1974 !prefixcmp(refname, "refs/notes/") ||
1975 !strcmp(refname, "HEAD"))) {
1976 if (safe_create_leading_directories(logfile) < 0)
1977 return error("unable to create directory for %s",
1978 logfile);
1979 oflags |= O_CREAT;
1982 logfd = open(logfile, oflags, 0666);
1983 if (logfd < 0) {
1984 if (!(oflags & O_CREAT) && errno == ENOENT)
1985 return 0;
1987 if ((oflags & O_CREAT) && errno == EISDIR) {
1988 if (remove_empty_directories(logfile)) {
1989 return error("There are still logs under '%s'",
1990 logfile);
1992 logfd = open(logfile, oflags, 0666);
1995 if (logfd < 0)
1996 return error("Unable to append to %s: %s",
1997 logfile, strerror(errno));
2000 adjust_shared_perm(logfile);
2001 close(logfd);
2002 return 0;
2005 static int log_ref_write(const char *refname, const unsigned char *old_sha1,
2006 const unsigned char *new_sha1, const char *msg)
2008 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
2009 unsigned maxlen, len;
2010 int msglen;
2011 char log_file[PATH_MAX];
2012 char *logrec;
2013 const char *committer;
2015 if (log_all_ref_updates < 0)
2016 log_all_ref_updates = !is_bare_repository();
2018 result = log_ref_setup(refname, log_file, sizeof(log_file));
2019 if (result)
2020 return result;
2022 logfd = open(log_file, oflags);
2023 if (logfd < 0)
2024 return 0;
2025 msglen = msg ? strlen(msg) : 0;
2026 committer = git_committer_info(0);
2027 maxlen = strlen(committer) + msglen + 100;
2028 logrec = xmalloc(maxlen);
2029 len = sprintf(logrec, "%s %s %s\n",
2030 sha1_to_hex(old_sha1),
2031 sha1_to_hex(new_sha1),
2032 committer);
2033 if (msglen)
2034 len += copy_msg(logrec + len - 1, msg) - 1;
2035 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
2036 free(logrec);
2037 if (close(logfd) != 0 || written != len)
2038 return error("Unable to append to %s", log_file);
2039 return 0;
2042 static int is_branch(const char *refname)
2044 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
2047 int write_ref_sha1(struct ref_lock *lock,
2048 const unsigned char *sha1, const char *logmsg)
2050 static char term = '\n';
2051 struct object *o;
2053 if (!lock)
2054 return -1;
2055 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
2056 unlock_ref(lock);
2057 return 0;
2059 o = parse_object(sha1);
2060 if (!o) {
2061 error("Trying to write ref %s with nonexistent object %s",
2062 lock->ref_name, sha1_to_hex(sha1));
2063 unlock_ref(lock);
2064 return -1;
2066 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
2067 error("Trying to write non-commit object %s to branch %s",
2068 sha1_to_hex(sha1), lock->ref_name);
2069 unlock_ref(lock);
2070 return -1;
2072 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
2073 write_in_full(lock->lock_fd, &term, 1) != 1
2074 || close_ref(lock) < 0) {
2075 error("Couldn't write %s", lock->lk->filename);
2076 unlock_ref(lock);
2077 return -1;
2079 clear_loose_ref_cache(get_ref_cache(NULL));
2080 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
2081 (strcmp(lock->ref_name, lock->orig_ref_name) &&
2082 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
2083 unlock_ref(lock);
2084 return -1;
2086 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
2088 * Special hack: If a branch is updated directly and HEAD
2089 * points to it (may happen on the remote side of a push
2090 * for example) then logically the HEAD reflog should be
2091 * updated too.
2092 * A generic solution implies reverse symref information,
2093 * but finding all symrefs pointing to the given branch
2094 * would be rather costly for this rare event (the direct
2095 * update of a branch) to be worth it. So let's cheat and
2096 * check with HEAD only which should cover 99% of all usage
2097 * scenarios (even 100% of the default ones).
2099 unsigned char head_sha1[20];
2100 int head_flag;
2101 const char *head_ref;
2102 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
2103 if (head_ref && (head_flag & REF_ISSYMREF) &&
2104 !strcmp(head_ref, lock->ref_name))
2105 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
2107 if (commit_ref(lock)) {
2108 error("Couldn't set %s", lock->ref_name);
2109 unlock_ref(lock);
2110 return -1;
2112 unlock_ref(lock);
2113 return 0;
2116 int create_symref(const char *ref_target, const char *refs_heads_master,
2117 const char *logmsg)
2119 const char *lockpath;
2120 char ref[1000];
2121 int fd, len, written;
2122 char *git_HEAD = git_pathdup("%s", ref_target);
2123 unsigned char old_sha1[20], new_sha1[20];
2125 if (logmsg && read_ref(ref_target, old_sha1))
2126 hashclr(old_sha1);
2128 if (safe_create_leading_directories(git_HEAD) < 0)
2129 return error("unable to create directory for %s", git_HEAD);
2131 #ifndef NO_SYMLINK_HEAD
2132 if (prefer_symlink_refs) {
2133 unlink(git_HEAD);
2134 if (!symlink(refs_heads_master, git_HEAD))
2135 goto done;
2136 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
2138 #endif
2140 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
2141 if (sizeof(ref) <= len) {
2142 error("refname too long: %s", refs_heads_master);
2143 goto error_free_return;
2145 lockpath = mkpath("%s.lock", git_HEAD);
2146 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
2147 if (fd < 0) {
2148 error("Unable to open %s for writing", lockpath);
2149 goto error_free_return;
2151 written = write_in_full(fd, ref, len);
2152 if (close(fd) != 0 || written != len) {
2153 error("Unable to write to %s", lockpath);
2154 goto error_unlink_return;
2156 if (rename(lockpath, git_HEAD) < 0) {
2157 error("Unable to create %s", git_HEAD);
2158 goto error_unlink_return;
2160 if (adjust_shared_perm(git_HEAD)) {
2161 error("Unable to fix permissions on %s", lockpath);
2162 error_unlink_return:
2163 unlink_or_warn(lockpath);
2164 error_free_return:
2165 free(git_HEAD);
2166 return -1;
2169 #ifndef NO_SYMLINK_HEAD
2170 done:
2171 #endif
2172 if (logmsg && !read_ref(refs_heads_master, new_sha1))
2173 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
2175 free(git_HEAD);
2176 return 0;
2179 static char *ref_msg(const char *line, const char *endp)
2181 const char *ep;
2182 line += 82;
2183 ep = memchr(line, '\n', endp - line);
2184 if (!ep)
2185 ep = endp;
2186 return xmemdupz(line, ep - line);
2189 int read_ref_at(const char *refname, unsigned long at_time, int cnt,
2190 unsigned char *sha1, char **msg,
2191 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
2193 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
2194 char *tz_c;
2195 int logfd, tz, reccnt = 0;
2196 struct stat st;
2197 unsigned long date;
2198 unsigned char logged_sha1[20];
2199 void *log_mapped;
2200 size_t mapsz;
2202 logfile = git_path("logs/%s", refname);
2203 logfd = open(logfile, O_RDONLY, 0);
2204 if (logfd < 0)
2205 die_errno("Unable to read log '%s'", logfile);
2206 fstat(logfd, &st);
2207 if (!st.st_size)
2208 die("Log %s is empty.", logfile);
2209 mapsz = xsize_t(st.st_size);
2210 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
2211 logdata = log_mapped;
2212 close(logfd);
2214 lastrec = NULL;
2215 rec = logend = logdata + st.st_size;
2216 while (logdata < rec) {
2217 reccnt++;
2218 if (logdata < rec && *(rec-1) == '\n')
2219 rec--;
2220 lastgt = NULL;
2221 while (logdata < rec && *(rec-1) != '\n') {
2222 rec--;
2223 if (*rec == '>')
2224 lastgt = rec;
2226 if (!lastgt)
2227 die("Log %s is corrupt.", logfile);
2228 date = strtoul(lastgt + 1, &tz_c, 10);
2229 if (date <= at_time || cnt == 0) {
2230 tz = strtoul(tz_c, NULL, 10);
2231 if (msg)
2232 *msg = ref_msg(rec, logend);
2233 if (cutoff_time)
2234 *cutoff_time = date;
2235 if (cutoff_tz)
2236 *cutoff_tz = tz;
2237 if (cutoff_cnt)
2238 *cutoff_cnt = reccnt - 1;
2239 if (lastrec) {
2240 if (get_sha1_hex(lastrec, logged_sha1))
2241 die("Log %s is corrupt.", logfile);
2242 if (get_sha1_hex(rec + 41, sha1))
2243 die("Log %s is corrupt.", logfile);
2244 if (hashcmp(logged_sha1, sha1)) {
2245 warning("Log %s has gap after %s.",
2246 logfile, show_date(date, tz, DATE_RFC2822));
2249 else if (date == at_time) {
2250 if (get_sha1_hex(rec + 41, sha1))
2251 die("Log %s is corrupt.", logfile);
2253 else {
2254 if (get_sha1_hex(rec + 41, logged_sha1))
2255 die("Log %s is corrupt.", logfile);
2256 if (hashcmp(logged_sha1, sha1)) {
2257 warning("Log %s unexpectedly ended on %s.",
2258 logfile, show_date(date, tz, DATE_RFC2822));
2261 munmap(log_mapped, mapsz);
2262 return 0;
2264 lastrec = rec;
2265 if (cnt > 0)
2266 cnt--;
2269 rec = logdata;
2270 while (rec < logend && *rec != '>' && *rec != '\n')
2271 rec++;
2272 if (rec == logend || *rec == '\n')
2273 die("Log %s is corrupt.", logfile);
2274 date = strtoul(rec + 1, &tz_c, 10);
2275 tz = strtoul(tz_c, NULL, 10);
2276 if (get_sha1_hex(logdata, sha1))
2277 die("Log %s is corrupt.", logfile);
2278 if (is_null_sha1(sha1)) {
2279 if (get_sha1_hex(logdata + 41, sha1))
2280 die("Log %s is corrupt.", logfile);
2282 if (msg)
2283 *msg = ref_msg(logdata, logend);
2284 munmap(log_mapped, mapsz);
2286 if (cutoff_time)
2287 *cutoff_time = date;
2288 if (cutoff_tz)
2289 *cutoff_tz = tz;
2290 if (cutoff_cnt)
2291 *cutoff_cnt = reccnt;
2292 return 1;
2295 int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
2297 const char *logfile;
2298 FILE *logfp;
2299 struct strbuf sb = STRBUF_INIT;
2300 int ret = 0;
2302 logfile = git_path("logs/%s", refname);
2303 logfp = fopen(logfile, "r");
2304 if (!logfp)
2305 return -1;
2307 if (ofs) {
2308 struct stat statbuf;
2309 if (fstat(fileno(logfp), &statbuf) ||
2310 statbuf.st_size < ofs ||
2311 fseek(logfp, -ofs, SEEK_END) ||
2312 strbuf_getwholeline(&sb, logfp, '\n')) {
2313 fclose(logfp);
2314 strbuf_release(&sb);
2315 return -1;
2319 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
2320 unsigned char osha1[20], nsha1[20];
2321 char *email_end, *message;
2322 unsigned long timestamp;
2323 int tz;
2325 /* old SP new SP name <email> SP time TAB msg LF */
2326 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
2327 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
2328 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
2329 !(email_end = strchr(sb.buf + 82, '>')) ||
2330 email_end[1] != ' ' ||
2331 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
2332 !message || message[0] != ' ' ||
2333 (message[1] != '+' && message[1] != '-') ||
2334 !isdigit(message[2]) || !isdigit(message[3]) ||
2335 !isdigit(message[4]) || !isdigit(message[5]))
2336 continue; /* corrupt? */
2337 email_end[1] = '\0';
2338 tz = strtol(message + 1, NULL, 10);
2339 if (message[6] != '\t')
2340 message += 6;
2341 else
2342 message += 7;
2343 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
2344 cb_data);
2345 if (ret)
2346 break;
2348 fclose(logfp);
2349 strbuf_release(&sb);
2350 return ret;
2353 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
2355 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
2359 * Call fn for each reflog in the namespace indicated by name. name
2360 * must be empty or end with '/'. Name will be used as a scratch
2361 * space, but its contents will be restored before return.
2363 static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)
2365 DIR *d = opendir(git_path("logs/%s", name->buf));
2366 int retval = 0;
2367 struct dirent *de;
2368 int oldlen = name->len;
2370 if (!d)
2371 return name->len ? errno : 0;
2373 while ((de = readdir(d)) != NULL) {
2374 struct stat st;
2376 if (de->d_name[0] == '.')
2377 continue;
2378 if (has_extension(de->d_name, ".lock"))
2379 continue;
2380 strbuf_addstr(name, de->d_name);
2381 if (stat(git_path("logs/%s", name->buf), &st) < 0) {
2382 ; /* silently ignore */
2383 } else {
2384 if (S_ISDIR(st.st_mode)) {
2385 strbuf_addch(name, '/');
2386 retval = do_for_each_reflog(name, fn, cb_data);
2387 } else {
2388 unsigned char sha1[20];
2389 if (read_ref_full(name->buf, sha1, 0, NULL))
2390 retval = error("bad ref for %s", name->buf);
2391 else
2392 retval = fn(name->buf, sha1, 0, cb_data);
2394 if (retval)
2395 break;
2397 strbuf_setlen(name, oldlen);
2399 closedir(d);
2400 return retval;
2403 int for_each_reflog(each_ref_fn fn, void *cb_data)
2405 int retval;
2406 struct strbuf name;
2407 strbuf_init(&name, PATH_MAX);
2408 retval = do_for_each_reflog(&name, fn, cb_data);
2409 strbuf_release(&name);
2410 return retval;
2413 int update_ref(const char *action, const char *refname,
2414 const unsigned char *sha1, const unsigned char *oldval,
2415 int flags, enum action_on_err onerr)
2417 static struct ref_lock *lock;
2418 lock = lock_any_ref_for_update(refname, oldval, flags);
2419 if (!lock) {
2420 const char *str = "Cannot lock the ref '%s'.";
2421 switch (onerr) {
2422 case MSG_ON_ERR: error(str, refname); break;
2423 case DIE_ON_ERR: die(str, refname); break;
2424 case QUIET_ON_ERR: break;
2426 return 1;
2428 if (write_ref_sha1(lock, sha1, action) < 0) {
2429 const char *str = "Cannot update the ref '%s'.";
2430 switch (onerr) {
2431 case MSG_ON_ERR: error(str, refname); break;
2432 case DIE_ON_ERR: die(str, refname); break;
2433 case QUIET_ON_ERR: break;
2435 return 1;
2437 return 0;
2440 struct ref *find_ref_by_name(const struct ref *list, const char *name)
2442 for ( ; list; list = list->next)
2443 if (!strcmp(list->name, name))
2444 return (struct ref *)list;
2445 return NULL;
2449 * generate a format suitable for scanf from a ref_rev_parse_rules
2450 * rule, that is replace the "%.*s" spec with a "%s" spec
2452 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2454 char *spec;
2456 spec = strstr(rule, "%.*s");
2457 if (!spec || strstr(spec + 4, "%.*s"))
2458 die("invalid rule in ref_rev_parse_rules: %s", rule);
2460 /* copy all until spec */
2461 strncpy(scanf_fmt, rule, spec - rule);
2462 scanf_fmt[spec - rule] = '\0';
2463 /* copy new spec */
2464 strcat(scanf_fmt, "%s");
2465 /* copy remaining rule */
2466 strcat(scanf_fmt, spec + 4);
2468 return;
2471 char *shorten_unambiguous_ref(const char *refname, int strict)
2473 int i;
2474 static char **scanf_fmts;
2475 static int nr_rules;
2476 char *short_name;
2478 /* pre generate scanf formats from ref_rev_parse_rules[] */
2479 if (!nr_rules) {
2480 size_t total_len = 0;
2482 /* the rule list is NULL terminated, count them first */
2483 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2484 /* no +1 because strlen("%s") < strlen("%.*s") */
2485 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2487 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2489 total_len = 0;
2490 for (i = 0; i < nr_rules; i++) {
2491 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2492 + total_len;
2493 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2494 total_len += strlen(ref_rev_parse_rules[i]);
2498 /* bail out if there are no rules */
2499 if (!nr_rules)
2500 return xstrdup(refname);
2502 /* buffer for scanf result, at most refname must fit */
2503 short_name = xstrdup(refname);
2505 /* skip first rule, it will always match */
2506 for (i = nr_rules - 1; i > 0 ; --i) {
2507 int j;
2508 int rules_to_fail = i;
2509 int short_name_len;
2511 if (1 != sscanf(refname, scanf_fmts[i], short_name))
2512 continue;
2514 short_name_len = strlen(short_name);
2517 * in strict mode, all (except the matched one) rules
2518 * must fail to resolve to a valid non-ambiguous ref
2520 if (strict)
2521 rules_to_fail = nr_rules;
2524 * check if the short name resolves to a valid ref,
2525 * but use only rules prior to the matched one
2527 for (j = 0; j < rules_to_fail; j++) {
2528 const char *rule = ref_rev_parse_rules[j];
2529 char refname[PATH_MAX];
2531 /* skip matched rule */
2532 if (i == j)
2533 continue;
2536 * the short name is ambiguous, if it resolves
2537 * (with this previous rule) to a valid ref
2538 * read_ref() returns 0 on success
2540 mksnpath(refname, sizeof(refname),
2541 rule, short_name_len, short_name);
2542 if (ref_exists(refname))
2543 break;
2547 * short name is non-ambiguous if all previous rules
2548 * haven't resolved to a valid ref
2550 if (j == rules_to_fail)
2551 return short_name;
2554 free(short_name);
2555 return xstrdup(refname);