Revert "compat: add strtok_r()"
[git/mingw.git] / refs.c
blob175b9fcaa25eba2ad02564b32eba04c3351978c5
1 #include "cache.h"
2 #include "refs.h"
3 #include "object.h"
4 #include "tag.h"
5 #include "dir.h"
6 #include "string-list.h"
8 /*
9 * Make sure "ref" is something reasonable to have under ".git/refs/";
10 * We do not like it if:
12 * - any path component of it begins with ".", or
13 * - it has double dots "..", or
14 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
15 * - it ends with a "/".
16 * - it ends with ".lock"
17 * - it contains a "\" (backslash)
20 /* Return true iff ch is not allowed in reference names. */
21 static inline int bad_ref_char(int ch)
23 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
24 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
25 return 1;
26 /* 2.13 Pattern Matching Notation */
27 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
28 return 1;
29 return 0;
33 * Try to read one refname component from the front of refname. Return
34 * the length of the component found, or -1 if the component is not
35 * legal.
37 static int check_refname_component(const char *refname, int flags)
39 const char *cp;
40 char last = '\0';
42 for (cp = refname; ; cp++) {
43 char ch = *cp;
44 if (ch == '\0' || ch == '/')
45 break;
46 if (bad_ref_char(ch))
47 return -1; /* Illegal character in refname. */
48 if (last == '.' && ch == '.')
49 return -1; /* Refname contains "..". */
50 if (last == '@' && ch == '{')
51 return -1; /* Refname contains "@{". */
52 last = ch;
54 if (cp == refname)
55 return 0; /* Component has zero length. */
56 if (refname[0] == '.') {
57 if (!(flags & REFNAME_DOT_COMPONENT))
58 return -1; /* Component starts with '.'. */
60 * Even if leading dots are allowed, don't allow "."
61 * as a component (".." is prevented by a rule above).
63 if (refname[1] == '\0')
64 return -1; /* Component equals ".". */
66 if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5))
67 return -1; /* Refname ends with ".lock". */
68 return cp - refname;
71 int check_refname_format(const char *refname, int flags)
73 int component_len, component_count = 0;
75 while (1) {
76 /* We are at the start of a path component. */
77 component_len = check_refname_component(refname, flags);
78 if (component_len <= 0) {
79 if ((flags & REFNAME_REFSPEC_PATTERN) &&
80 refname[0] == '*' &&
81 (refname[1] == '\0' || refname[1] == '/')) {
82 /* Accept one wildcard as a full refname component. */
83 flags &= ~REFNAME_REFSPEC_PATTERN;
84 component_len = 1;
85 } else {
86 return -1;
89 component_count++;
90 if (refname[component_len] == '\0')
91 break;
92 /* Skip to next component. */
93 refname += component_len + 1;
96 if (refname[component_len - 1] == '.')
97 return -1; /* Refname ends with '.'. */
98 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
99 return -1; /* Refname has only one component. */
100 return 0;
103 struct ref_entry;
106 * Information used (along with the information in ref_entry) to
107 * describe a single cached reference. This data structure only
108 * occurs embedded in a union in struct ref_entry, and only when
109 * (ref_entry->flag & REF_DIR) is zero.
111 struct ref_value {
112 unsigned char sha1[20];
113 unsigned char peeled[20];
116 struct ref_cache;
119 * Information used (along with the information in ref_entry) to
120 * describe a level in the hierarchy of references. This data
121 * structure only occurs embedded in a union in struct ref_entry, and
122 * only when (ref_entry.flag & REF_DIR) is set. In that case,
123 * (ref_entry.flag & REF_INCOMPLETE) determines whether the references
124 * in the directory have already been read:
126 * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose
127 * or packed references, already read.
129 * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose
130 * references that hasn't been read yet (nor has any of its
131 * subdirectories).
133 * Entries within a directory are stored within a growable array of
134 * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i <
135 * sorted are sorted by their component name in strcmp() order and the
136 * remaining entries are unsorted.
138 * Loose references are read lazily, one directory at a time. When a
139 * directory of loose references is read, then all of the references
140 * in that directory are stored, and REF_INCOMPLETE stubs are created
141 * for any subdirectories, but the subdirectories themselves are not
142 * read. The reading is triggered by get_ref_dir().
144 struct ref_dir {
145 int nr, alloc;
148 * Entries with index 0 <= i < sorted are sorted by name. New
149 * entries are appended to the list unsorted, and are sorted
150 * only when required; thus we avoid the need to sort the list
151 * after the addition of every reference.
153 int sorted;
155 /* A pointer to the ref_cache that contains this ref_dir. */
156 struct ref_cache *ref_cache;
158 struct ref_entry **entries;
161 /* ISSYMREF=0x01, ISPACKED=0x02, and ISBROKEN=0x04 are public interfaces */
162 #define REF_KNOWS_PEELED 0x08
164 /* ref_entry represents a directory of references */
165 #define REF_DIR 0x10
168 * Entry has not yet been read from disk (used only for REF_DIR
169 * entries representing loose references)
171 #define REF_INCOMPLETE 0x20
174 * A ref_entry represents either a reference or a "subdirectory" of
175 * references.
177 * Each directory in the reference namespace is represented by a
178 * ref_entry with (flags & REF_DIR) set and containing a subdir member
179 * that holds the entries in that directory that have been read so
180 * far. If (flags & REF_INCOMPLETE) is set, then the directory and
181 * its subdirectories haven't been read yet. REF_INCOMPLETE is only
182 * used for loose reference directories.
184 * References are represented by a ref_entry with (flags & REF_DIR)
185 * unset and a value member that describes the reference's value. The
186 * flag member is at the ref_entry level, but it is also needed to
187 * interpret the contents of the value field (in other words, a
188 * ref_value object is not very much use without the enclosing
189 * ref_entry).
191 * Reference names cannot end with slash and directories' names are
192 * always stored with a trailing slash (except for the top-level
193 * directory, which is always denoted by ""). This has two nice
194 * consequences: (1) when the entries in each subdir are sorted
195 * lexicographically by name (as they usually are), the references in
196 * a whole tree can be generated in lexicographic order by traversing
197 * the tree in left-to-right, depth-first order; (2) the names of
198 * references and subdirectories cannot conflict, and therefore the
199 * presence of an empty subdirectory does not block the creation of a
200 * similarly-named reference. (The fact that reference names with the
201 * same leading components can conflict *with each other* is a
202 * separate issue that is regulated by is_refname_available().)
204 * Please note that the name field contains the fully-qualified
205 * reference (or subdirectory) name. Space could be saved by only
206 * storing the relative names. But that would require the full names
207 * to be generated on the fly when iterating in do_for_each_ref(), and
208 * would break callback functions, who have always been able to assume
209 * that the name strings that they are passed will not be freed during
210 * the iteration.
212 struct ref_entry {
213 unsigned char flag; /* ISSYMREF? ISPACKED? */
214 union {
215 struct ref_value value; /* if not (flags&REF_DIR) */
216 struct ref_dir subdir; /* if (flags&REF_DIR) */
217 } u;
219 * The full name of the reference (e.g., "refs/heads/master")
220 * or the full name of the directory with a trailing slash
221 * (e.g., "refs/heads/"):
223 char name[FLEX_ARRAY];
226 static void read_loose_refs(const char *dirname, struct ref_dir *dir);
228 static struct ref_dir *get_ref_dir(struct ref_entry *entry)
230 struct ref_dir *dir;
231 assert(entry->flag & REF_DIR);
232 dir = &entry->u.subdir;
233 if (entry->flag & REF_INCOMPLETE) {
234 read_loose_refs(entry->name, dir);
235 entry->flag &= ~REF_INCOMPLETE;
237 return dir;
240 static struct ref_entry *create_ref_entry(const char *refname,
241 const unsigned char *sha1, int flag,
242 int check_name)
244 int len;
245 struct ref_entry *ref;
247 if (check_name &&
248 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
249 die("Reference has invalid format: '%s'", refname);
250 len = strlen(refname) + 1;
251 ref = xmalloc(sizeof(struct ref_entry) + len);
252 hashcpy(ref->u.value.sha1, sha1);
253 hashclr(ref->u.value.peeled);
254 memcpy(ref->name, refname, len);
255 ref->flag = flag;
256 return ref;
259 static void clear_ref_dir(struct ref_dir *dir);
261 static void free_ref_entry(struct ref_entry *entry)
263 if (entry->flag & REF_DIR) {
265 * Do not use get_ref_dir() here, as that might
266 * trigger the reading of loose refs.
268 clear_ref_dir(&entry->u.subdir);
270 free(entry);
274 * Add a ref_entry to the end of dir (unsorted). Entry is always
275 * stored directly in dir; no recursion into subdirectories is
276 * done.
278 static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry)
280 ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc);
281 dir->entries[dir->nr++] = entry;
282 /* optimize for the case that entries are added in order */
283 if (dir->nr == 1 ||
284 (dir->nr == dir->sorted + 1 &&
285 strcmp(dir->entries[dir->nr - 2]->name,
286 dir->entries[dir->nr - 1]->name) < 0))
287 dir->sorted = dir->nr;
291 * Clear and free all entries in dir, recursively.
293 static void clear_ref_dir(struct ref_dir *dir)
295 int i;
296 for (i = 0; i < dir->nr; i++)
297 free_ref_entry(dir->entries[i]);
298 free(dir->entries);
299 dir->sorted = dir->nr = dir->alloc = 0;
300 dir->entries = NULL;
304 * Create a struct ref_entry object for the specified dirname.
305 * dirname is the name of the directory with a trailing slash (e.g.,
306 * "refs/heads/") or "" for the top-level directory.
308 static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache,
309 const char *dirname, size_t len,
310 int incomplete)
312 struct ref_entry *direntry;
313 direntry = xcalloc(1, sizeof(struct ref_entry) + len + 1);
314 memcpy(direntry->name, dirname, len);
315 direntry->name[len] = '\0';
316 direntry->u.subdir.ref_cache = ref_cache;
317 direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE : 0);
318 return direntry;
321 static int ref_entry_cmp(const void *a, const void *b)
323 struct ref_entry *one = *(struct ref_entry **)a;
324 struct ref_entry *two = *(struct ref_entry **)b;
325 return strcmp(one->name, two->name);
328 static void sort_ref_dir(struct ref_dir *dir);
330 struct string_slice {
331 size_t len;
332 const char *str;
335 static int ref_entry_cmp_sslice(const void *key_, const void *ent_)
337 const struct string_slice *key = key_;
338 const struct ref_entry *ent = *(const struct ref_entry * const *)ent_;
339 int cmp = strncmp(key->str, ent->name, key->len);
340 if (cmp)
341 return cmp;
342 return '\0' - (unsigned char)ent->name[key->len];
346 * Return the entry with the given refname from the ref_dir
347 * (non-recursively), sorting dir if necessary. Return NULL if no
348 * such entry is found. dir must already be complete.
350 static struct ref_entry *search_ref_dir(struct ref_dir *dir,
351 const char *refname, size_t len)
353 struct ref_entry **r;
354 struct string_slice key;
356 if (refname == NULL || !dir->nr)
357 return NULL;
359 sort_ref_dir(dir);
360 key.len = len;
361 key.str = refname;
362 r = bsearch(&key, dir->entries, dir->nr, sizeof(*dir->entries),
363 ref_entry_cmp_sslice);
365 if (r == NULL)
366 return NULL;
368 return *r;
372 * Search for a directory entry directly within dir (without
373 * recursing). Sort dir if necessary. subdirname must be a directory
374 * name (i.e., end in '/'). If mkdir is set, then create the
375 * directory if it is missing; otherwise, return NULL if the desired
376 * directory cannot be found. dir must already be complete.
378 static struct ref_dir *search_for_subdir(struct ref_dir *dir,
379 const char *subdirname, size_t len,
380 int mkdir)
382 struct ref_entry *entry = search_ref_dir(dir, subdirname, len);
383 if (!entry) {
384 if (!mkdir)
385 return NULL;
387 * Since dir is complete, the absence of a subdir
388 * means that the subdir really doesn't exist;
389 * therefore, create an empty record for it but mark
390 * the record complete.
392 entry = create_dir_entry(dir->ref_cache, subdirname, len, 0);
393 add_entry_to_dir(dir, entry);
395 return get_ref_dir(entry);
399 * If refname is a reference name, find the ref_dir within the dir
400 * tree that should hold refname. If refname is a directory name
401 * (i.e., ends in '/'), then return that ref_dir itself. dir must
402 * represent the top-level directory and must already be complete.
403 * Sort ref_dirs and recurse into subdirectories as necessary. If
404 * mkdir is set, then create any missing directories; otherwise,
405 * return NULL if the desired directory cannot be found.
407 static struct ref_dir *find_containing_dir(struct ref_dir *dir,
408 const char *refname, int mkdir)
410 const char *slash;
411 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
412 size_t dirnamelen = slash - refname + 1;
413 struct ref_dir *subdir;
414 subdir = search_for_subdir(dir, refname, dirnamelen, mkdir);
415 if (!subdir) {
416 dir = NULL;
417 break;
419 dir = subdir;
422 return dir;
426 * Find the value entry with the given name in dir, sorting ref_dirs
427 * and recursing into subdirectories as necessary. If the name is not
428 * found or it corresponds to a directory entry, return NULL.
430 static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname)
432 struct ref_entry *entry;
433 dir = find_containing_dir(dir, refname, 0);
434 if (!dir)
435 return NULL;
436 entry = search_ref_dir(dir, refname, strlen(refname));
437 return (entry && !(entry->flag & REF_DIR)) ? entry : NULL;
441 * Add a ref_entry to the ref_dir (unsorted), recursing into
442 * subdirectories as necessary. dir must represent the top-level
443 * directory. Return 0 on success.
445 static int add_ref(struct ref_dir *dir, struct ref_entry *ref)
447 dir = find_containing_dir(dir, ref->name, 1);
448 if (!dir)
449 return -1;
450 add_entry_to_dir(dir, ref);
451 return 0;
455 * Emit a warning and return true iff ref1 and ref2 have the same name
456 * and the same sha1. Die if they have the same name but different
457 * sha1s.
459 static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
461 if (strcmp(ref1->name, ref2->name))
462 return 0;
464 /* Duplicate name; make sure that they don't conflict: */
466 if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR))
467 /* This is impossible by construction */
468 die("Reference directory conflict: %s", ref1->name);
470 if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1))
471 die("Duplicated ref, and SHA1s don't match: %s", ref1->name);
473 warning("Duplicated ref: %s", ref1->name);
474 return 1;
478 * Sort the entries in dir non-recursively (if they are not already
479 * sorted) and remove any duplicate entries.
481 static void sort_ref_dir(struct ref_dir *dir)
483 int i, j;
484 struct ref_entry *last = NULL;
487 * This check also prevents passing a zero-length array to qsort(),
488 * which is a problem on some platforms.
490 if (dir->sorted == dir->nr)
491 return;
493 qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp);
495 /* Remove any duplicates: */
496 for (i = 0, j = 0; j < dir->nr; j++) {
497 struct ref_entry *entry = dir->entries[j];
498 if (last && is_dup_ref(last, entry))
499 free_ref_entry(entry);
500 else
501 last = dir->entries[i++] = entry;
503 dir->sorted = dir->nr = i;
506 #define DO_FOR_EACH_INCLUDE_BROKEN 01
508 static struct ref_entry *current_ref;
510 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
511 int flags, void *cb_data, struct ref_entry *entry)
513 int retval;
514 if (prefixcmp(entry->name, base))
515 return 0;
517 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
518 if (entry->flag & REF_ISBROKEN)
519 return 0; /* ignore broken refs e.g. dangling symref */
520 if (!has_sha1_file(entry->u.value.sha1)) {
521 error("%s does not point to a valid object!", entry->name);
522 return 0;
525 current_ref = entry;
526 retval = fn(entry->name + trim, entry->u.value.sha1, entry->flag, cb_data);
527 current_ref = NULL;
528 return retval;
532 * Call fn for each reference in dir that has index in the range
533 * offset <= index < dir->nr. Recurse into subdirectories that are in
534 * that index range, sorting them before iterating. This function
535 * does not sort dir itself; it should be sorted beforehand.
537 static int do_for_each_ref_in_dir(struct ref_dir *dir, int offset,
538 const char *base,
539 each_ref_fn fn, int trim, int flags, void *cb_data)
541 int i;
542 assert(dir->sorted == dir->nr);
543 for (i = offset; i < dir->nr; i++) {
544 struct ref_entry *entry = dir->entries[i];
545 int retval;
546 if (entry->flag & REF_DIR) {
547 struct ref_dir *subdir = get_ref_dir(entry);
548 sort_ref_dir(subdir);
549 retval = do_for_each_ref_in_dir(subdir, 0,
550 base, fn, trim, flags, cb_data);
551 } else {
552 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
554 if (retval)
555 return retval;
557 return 0;
561 * Call fn for each reference in the union of dir1 and dir2, in order
562 * by refname. Recurse into subdirectories. If a value entry appears
563 * in both dir1 and dir2, then only process the version that is in
564 * dir2. The input dirs must already be sorted, but subdirs will be
565 * sorted as needed.
567 static int do_for_each_ref_in_dirs(struct ref_dir *dir1,
568 struct ref_dir *dir2,
569 const char *base, each_ref_fn fn, int trim,
570 int flags, void *cb_data)
572 int retval;
573 int i1 = 0, i2 = 0;
575 assert(dir1->sorted == dir1->nr);
576 assert(dir2->sorted == dir2->nr);
577 while (1) {
578 struct ref_entry *e1, *e2;
579 int cmp;
580 if (i1 == dir1->nr) {
581 return do_for_each_ref_in_dir(dir2, i2,
582 base, fn, trim, flags, cb_data);
584 if (i2 == dir2->nr) {
585 return do_for_each_ref_in_dir(dir1, i1,
586 base, fn, trim, flags, cb_data);
588 e1 = dir1->entries[i1];
589 e2 = dir2->entries[i2];
590 cmp = strcmp(e1->name, e2->name);
591 if (cmp == 0) {
592 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) {
593 /* Both are directories; descend them in parallel. */
594 struct ref_dir *subdir1 = get_ref_dir(e1);
595 struct ref_dir *subdir2 = get_ref_dir(e2);
596 sort_ref_dir(subdir1);
597 sort_ref_dir(subdir2);
598 retval = do_for_each_ref_in_dirs(
599 subdir1, subdir2,
600 base, fn, trim, flags, cb_data);
601 i1++;
602 i2++;
603 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) {
604 /* Both are references; ignore the one from dir1. */
605 retval = do_one_ref(base, fn, trim, flags, cb_data, e2);
606 i1++;
607 i2++;
608 } else {
609 die("conflict between reference and directory: %s",
610 e1->name);
612 } else {
613 struct ref_entry *e;
614 if (cmp < 0) {
615 e = e1;
616 i1++;
617 } else {
618 e = e2;
619 i2++;
621 if (e->flag & REF_DIR) {
622 struct ref_dir *subdir = get_ref_dir(e);
623 sort_ref_dir(subdir);
624 retval = do_for_each_ref_in_dir(
625 subdir, 0,
626 base, fn, trim, flags, cb_data);
627 } else {
628 retval = do_one_ref(base, fn, trim, flags, cb_data, e);
631 if (retval)
632 return retval;
634 if (i1 < dir1->nr)
635 return do_for_each_ref_in_dir(dir1, i1,
636 base, fn, trim, flags, cb_data);
637 if (i2 < dir2->nr)
638 return do_for_each_ref_in_dir(dir2, i2,
639 base, fn, trim, flags, cb_data);
640 return 0;
644 * Return true iff refname1 and refname2 conflict with each other.
645 * Two reference names conflict if one of them exactly matches the
646 * leading components of the other; e.g., "foo/bar" conflicts with
647 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
648 * "foo/barbados".
650 static int names_conflict(const char *refname1, const char *refname2)
652 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
654 return (*refname1 == '\0' && *refname2 == '/')
655 || (*refname1 == '/' && *refname2 == '\0');
658 struct name_conflict_cb {
659 const char *refname;
660 const char *oldrefname;
661 const char *conflicting_refname;
664 static int name_conflict_fn(const char *existingrefname, const unsigned char *sha1,
665 int flags, void *cb_data)
667 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
668 if (data->oldrefname && !strcmp(data->oldrefname, existingrefname))
669 return 0;
670 if (names_conflict(data->refname, existingrefname)) {
671 data->conflicting_refname = existingrefname;
672 return 1;
674 return 0;
678 * Return true iff a reference named refname could be created without
679 * conflicting with the name of an existing reference in array. If
680 * oldrefname is non-NULL, ignore potential conflicts with oldrefname
681 * (e.g., because oldrefname is scheduled for deletion in the same
682 * operation).
684 static int is_refname_available(const char *refname, const char *oldrefname,
685 struct ref_dir *dir)
687 struct name_conflict_cb data;
688 data.refname = refname;
689 data.oldrefname = oldrefname;
690 data.conflicting_refname = NULL;
692 sort_ref_dir(dir);
693 if (do_for_each_ref_in_dir(dir, 0, "", name_conflict_fn,
694 0, DO_FOR_EACH_INCLUDE_BROKEN,
695 &data)) {
696 error("'%s' exists; cannot create '%s'",
697 data.conflicting_refname, refname);
698 return 0;
700 return 1;
704 * Future: need to be in "struct repository"
705 * when doing a full libification.
707 static struct ref_cache {
708 struct ref_cache *next;
709 struct ref_entry *loose;
710 struct ref_entry *packed;
711 /* The submodule name, or "" for the main repo. */
712 char name[FLEX_ARRAY];
713 } *ref_cache;
715 static void clear_packed_ref_cache(struct ref_cache *refs)
717 if (refs->packed) {
718 free_ref_entry(refs->packed);
719 refs->packed = NULL;
723 static void clear_loose_ref_cache(struct ref_cache *refs)
725 if (refs->loose) {
726 free_ref_entry(refs->loose);
727 refs->loose = NULL;
731 static struct ref_cache *create_ref_cache(const char *submodule)
733 int len;
734 struct ref_cache *refs;
735 if (!submodule)
736 submodule = "";
737 len = strlen(submodule) + 1;
738 refs = xcalloc(1, sizeof(struct ref_cache) + len);
739 memcpy(refs->name, submodule, len);
740 return refs;
744 * Return a pointer to a ref_cache for the specified submodule. For
745 * the main repository, use submodule==NULL. The returned structure
746 * will be allocated and initialized but not necessarily populated; it
747 * should not be freed.
749 static struct ref_cache *get_ref_cache(const char *submodule)
751 struct ref_cache *refs = ref_cache;
752 if (!submodule)
753 submodule = "";
754 while (refs) {
755 if (!strcmp(submodule, refs->name))
756 return refs;
757 refs = refs->next;
760 refs = create_ref_cache(submodule);
761 refs->next = ref_cache;
762 ref_cache = refs;
763 return refs;
766 void invalidate_ref_cache(const char *submodule)
768 struct ref_cache *refs = get_ref_cache(submodule);
769 clear_packed_ref_cache(refs);
770 clear_loose_ref_cache(refs);
774 * Parse one line from a packed-refs file. Write the SHA1 to sha1.
775 * Return a pointer to the refname within the line (null-terminated),
776 * or NULL if there was a problem.
778 static const char *parse_ref_line(char *line, unsigned char *sha1)
781 * 42: the answer to everything.
783 * In this case, it happens to be the answer to
784 * 40 (length of sha1 hex representation)
785 * +1 (space in between hex and name)
786 * +1 (newline at the end of the line)
788 int len = strlen(line) - 42;
790 if (len <= 0)
791 return NULL;
792 if (get_sha1_hex(line, sha1) < 0)
793 return NULL;
794 if (!isspace(line[40]))
795 return NULL;
796 line += 41;
797 if (isspace(*line))
798 return NULL;
799 if (line[len] != '\n')
800 return NULL;
801 line[len] = 0;
803 return line;
806 static void read_packed_refs(FILE *f, struct ref_dir *dir)
808 struct ref_entry *last = NULL;
809 char refline[PATH_MAX];
810 int flag = REF_ISPACKED;
812 while (fgets(refline, sizeof(refline), f)) {
813 unsigned char sha1[20];
814 const char *refname;
815 static const char header[] = "# pack-refs with:";
817 if (!strncmp(refline, header, sizeof(header)-1)) {
818 const char *traits = refline + sizeof(header) - 1;
819 if (strstr(traits, " peeled "))
820 flag |= REF_KNOWS_PEELED;
821 /* perhaps other traits later as well */
822 continue;
825 refname = parse_ref_line(refline, sha1);
826 if (refname) {
827 last = create_ref_entry(refname, sha1, flag, 1);
828 add_ref(dir, last);
829 continue;
831 if (last &&
832 refline[0] == '^' &&
833 strlen(refline) == 42 &&
834 refline[41] == '\n' &&
835 !get_sha1_hex(refline + 1, sha1))
836 hashcpy(last->u.value.peeled, sha1);
840 static struct ref_dir *get_packed_refs(struct ref_cache *refs)
842 if (!refs->packed) {
843 const char *packed_refs_file;
844 FILE *f;
846 refs->packed = create_dir_entry(refs, "", 0, 0);
847 if (*refs->name)
848 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
849 else
850 packed_refs_file = git_path("packed-refs");
851 f = fopen(packed_refs_file, "r");
852 if (f) {
853 read_packed_refs(f, get_ref_dir(refs->packed));
854 fclose(f);
857 return get_ref_dir(refs->packed);
860 void add_packed_ref(const char *refname, const unsigned char *sha1)
862 add_ref(get_packed_refs(get_ref_cache(NULL)),
863 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
867 * Read the loose references from the namespace dirname into dir
868 * (without recursing). dirname must end with '/'. dir must be the
869 * directory entry corresponding to dirname.
871 static void read_loose_refs(const char *dirname, struct ref_dir *dir)
873 struct ref_cache *refs = dir->ref_cache;
874 DIR *d;
875 const char *path;
876 struct dirent *de;
877 int dirnamelen = strlen(dirname);
878 struct strbuf refname;
880 if (*refs->name)
881 path = git_path_submodule(refs->name, "%s", dirname);
882 else
883 path = git_path("%s", dirname);
885 d = opendir(path);
886 if (!d)
887 return;
889 strbuf_init(&refname, dirnamelen + 257);
890 strbuf_add(&refname, dirname, dirnamelen);
892 while ((de = readdir(d)) != NULL) {
893 unsigned char sha1[20];
894 struct stat st;
895 int flag;
896 const char *refdir;
898 if (de->d_name[0] == '.')
899 continue;
900 if (has_extension(de->d_name, ".lock"))
901 continue;
902 strbuf_addstr(&refname, de->d_name);
903 refdir = *refs->name
904 ? git_path_submodule(refs->name, "%s", refname.buf)
905 : git_path("%s", refname.buf);
906 if (stat(refdir, &st) < 0) {
907 ; /* silently ignore */
908 } else if (S_ISDIR(st.st_mode)) {
909 strbuf_addch(&refname, '/');
910 add_entry_to_dir(dir,
911 create_dir_entry(refs, refname.buf,
912 refname.len, 1));
913 } else {
914 if (*refs->name) {
915 hashclr(sha1);
916 flag = 0;
917 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {
918 hashclr(sha1);
919 flag |= REF_ISBROKEN;
921 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {
922 hashclr(sha1);
923 flag |= REF_ISBROKEN;
925 add_entry_to_dir(dir,
926 create_ref_entry(refname.buf, sha1, flag, 1));
928 strbuf_setlen(&refname, dirnamelen);
930 strbuf_release(&refname);
931 closedir(d);
934 static struct ref_dir *get_loose_refs(struct ref_cache *refs)
936 if (!refs->loose) {
938 * Mark the top-level directory complete because we
939 * are about to read the only subdirectory that can
940 * hold references:
942 refs->loose = create_dir_entry(refs, "", 0, 0);
944 * Create an incomplete entry for "refs/":
946 add_entry_to_dir(get_ref_dir(refs->loose),
947 create_dir_entry(refs, "refs/", 5, 1));
949 return get_ref_dir(refs->loose);
952 /* We allow "recursive" symbolic refs. Only within reason, though */
953 #define MAXDEPTH 5
954 #define MAXREFLEN (1024)
957 * Called by resolve_gitlink_ref_recursive() after it failed to read
958 * from the loose refs in ref_cache refs. Find <refname> in the
959 * packed-refs file for the submodule.
961 static int resolve_gitlink_packed_ref(struct ref_cache *refs,
962 const char *refname, unsigned char *sha1)
964 struct ref_entry *ref;
965 struct ref_dir *dir = get_packed_refs(refs);
967 ref = find_ref(dir, refname);
968 if (ref == NULL)
969 return -1;
971 memcpy(sha1, ref->u.value.sha1, 20);
972 return 0;
975 static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
976 const char *refname, unsigned char *sha1,
977 int recursion)
979 int fd, len;
980 char buffer[128], *p;
981 char *path;
983 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
984 return -1;
985 path = *refs->name
986 ? git_path_submodule(refs->name, "%s", refname)
987 : git_path("%s", refname);
988 fd = open(path, O_RDONLY);
989 if (fd < 0)
990 return resolve_gitlink_packed_ref(refs, refname, sha1);
992 len = read(fd, buffer, sizeof(buffer)-1);
993 close(fd);
994 if (len < 0)
995 return -1;
996 while (len && isspace(buffer[len-1]))
997 len--;
998 buffer[len] = 0;
1000 /* Was it a detached head or an old-fashioned symlink? */
1001 if (!get_sha1_hex(buffer, sha1))
1002 return 0;
1004 /* Symref? */
1005 if (strncmp(buffer, "ref:", 4))
1006 return -1;
1007 p = buffer + 4;
1008 while (isspace(*p))
1009 p++;
1011 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
1014 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
1016 int len = strlen(path), retval;
1017 char *submodule;
1018 struct ref_cache *refs;
1020 while (len && path[len-1] == '/')
1021 len--;
1022 if (!len)
1023 return -1;
1024 submodule = xstrndup(path, len);
1025 refs = get_ref_cache(submodule);
1026 free(submodule);
1028 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
1029 return retval;
1033 * Try to read ref from the packed references. On success, set sha1
1034 * and return 0; otherwise, return -1.
1036 static int get_packed_ref(const char *refname, unsigned char *sha1)
1038 struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
1039 struct ref_entry *entry = find_ref(packed, refname);
1040 if (entry) {
1041 hashcpy(sha1, entry->u.value.sha1);
1042 return 0;
1044 return -1;
1047 const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
1049 int depth = MAXDEPTH;
1050 ssize_t len;
1051 char buffer[256];
1052 static char refname_buffer[256];
1054 if (flag)
1055 *flag = 0;
1057 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
1058 return NULL;
1060 for (;;) {
1061 char path[PATH_MAX];
1062 struct stat st;
1063 char *buf;
1064 int fd;
1066 if (--depth < 0)
1067 return NULL;
1069 git_snpath(path, sizeof(path), "%s", refname);
1071 if (lstat(path, &st) < 0) {
1072 if (errno != ENOENT)
1073 return NULL;
1075 * The loose reference file does not exist;
1076 * check for a packed reference.
1078 if (!get_packed_ref(refname, sha1)) {
1079 if (flag)
1080 *flag |= REF_ISPACKED;
1081 return refname;
1083 /* The reference is not a packed reference, either. */
1084 if (reading) {
1085 return NULL;
1086 } else {
1087 hashclr(sha1);
1088 return refname;
1092 /* Follow "normalized" - ie "refs/.." symlinks by hand */
1093 if (S_ISLNK(st.st_mode)) {
1094 len = readlink(path, buffer, sizeof(buffer)-1);
1095 if (len < 0)
1096 return NULL;
1097 buffer[len] = 0;
1098 if (!prefixcmp(buffer, "refs/") &&
1099 !check_refname_format(buffer, 0)) {
1100 strcpy(refname_buffer, buffer);
1101 refname = refname_buffer;
1102 if (flag)
1103 *flag |= REF_ISSYMREF;
1104 continue;
1108 /* Is it a directory? */
1109 if (S_ISDIR(st.st_mode)) {
1110 errno = EISDIR;
1111 return NULL;
1115 * Anything else, just open it and try to use it as
1116 * a ref
1118 fd = open(path, O_RDONLY);
1119 if (fd < 0)
1120 return NULL;
1121 len = read_in_full(fd, buffer, sizeof(buffer)-1);
1122 close(fd);
1123 if (len < 0)
1124 return NULL;
1125 while (len && isspace(buffer[len-1]))
1126 len--;
1127 buffer[len] = '\0';
1130 * Is it a symbolic ref?
1132 if (prefixcmp(buffer, "ref:"))
1133 break;
1134 if (flag)
1135 *flag |= REF_ISSYMREF;
1136 buf = buffer + 4;
1137 while (isspace(*buf))
1138 buf++;
1139 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
1140 if (flag)
1141 *flag |= REF_ISBROKEN;
1142 return NULL;
1144 refname = strcpy(refname_buffer, buf);
1146 /* Please note that FETCH_HEAD has a second line containing other data. */
1147 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
1148 if (flag)
1149 *flag |= REF_ISBROKEN;
1150 return NULL;
1152 return refname;
1155 char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
1157 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
1158 return ret ? xstrdup(ret) : NULL;
1161 /* The argument to filter_refs */
1162 struct ref_filter {
1163 const char *pattern;
1164 each_ref_fn *fn;
1165 void *cb_data;
1168 int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
1170 if (resolve_ref_unsafe(refname, sha1, reading, flags))
1171 return 0;
1172 return -1;
1175 int read_ref(const char *refname, unsigned char *sha1)
1177 return read_ref_full(refname, sha1, 1, NULL);
1180 int ref_exists(const char *refname)
1182 unsigned char sha1[20];
1183 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
1186 static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
1187 void *data)
1189 struct ref_filter *filter = (struct ref_filter *)data;
1190 if (fnmatch(filter->pattern, refname, 0))
1191 return 0;
1192 return filter->fn(refname, sha1, flags, filter->cb_data);
1195 int peel_ref(const char *refname, unsigned char *sha1)
1197 int flag;
1198 unsigned char base[20];
1199 struct object *o;
1201 if (current_ref && (current_ref->name == refname
1202 || !strcmp(current_ref->name, refname))) {
1203 if (current_ref->flag & REF_KNOWS_PEELED) {
1204 if (is_null_sha1(current_ref->u.value.peeled))
1205 return -1;
1206 hashcpy(sha1, current_ref->u.value.peeled);
1207 return 0;
1209 hashcpy(base, current_ref->u.value.sha1);
1210 goto fallback;
1213 if (read_ref_full(refname, base, 1, &flag))
1214 return -1;
1216 if ((flag & REF_ISPACKED)) {
1217 struct ref_dir *dir = get_packed_refs(get_ref_cache(NULL));
1218 struct ref_entry *r = find_ref(dir, refname);
1220 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
1221 hashcpy(sha1, r->u.value.peeled);
1222 return 0;
1226 fallback:
1227 o = lookup_unknown_object(base);
1228 if (o->type == OBJ_NONE) {
1229 int type = sha1_object_info(base, NULL);
1230 if (type < 0)
1231 return -1;
1232 o->type = type;
1235 if (o->type == OBJ_TAG) {
1236 o = deref_tag_noverify(o);
1237 if (o) {
1238 hashcpy(sha1, o->sha1);
1239 return 0;
1242 return -1;
1245 struct warn_if_dangling_data {
1246 FILE *fp;
1247 const char *refname;
1248 const char *msg_fmt;
1251 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
1252 int flags, void *cb_data)
1254 struct warn_if_dangling_data *d = cb_data;
1255 const char *resolves_to;
1256 unsigned char junk[20];
1258 if (!(flags & REF_ISSYMREF))
1259 return 0;
1261 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
1262 if (!resolves_to || strcmp(resolves_to, d->refname))
1263 return 0;
1265 fprintf(d->fp, d->msg_fmt, refname);
1266 fputc('\n', d->fp);
1267 return 0;
1270 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
1272 struct warn_if_dangling_data data;
1274 data.fp = fp;
1275 data.refname = refname;
1276 data.msg_fmt = msg_fmt;
1277 for_each_rawref(warn_if_dangling_symref, &data);
1280 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
1281 int trim, int flags, void *cb_data)
1283 struct ref_cache *refs = get_ref_cache(submodule);
1284 struct ref_dir *packed_dir = get_packed_refs(refs);
1285 struct ref_dir *loose_dir = get_loose_refs(refs);
1286 int retval = 0;
1288 if (base && *base) {
1289 packed_dir = find_containing_dir(packed_dir, base, 0);
1290 loose_dir = find_containing_dir(loose_dir, base, 0);
1293 if (packed_dir && loose_dir) {
1294 sort_ref_dir(packed_dir);
1295 sort_ref_dir(loose_dir);
1296 retval = do_for_each_ref_in_dirs(
1297 packed_dir, loose_dir,
1298 base, fn, trim, flags, cb_data);
1299 } else if (packed_dir) {
1300 sort_ref_dir(packed_dir);
1301 retval = do_for_each_ref_in_dir(
1302 packed_dir, 0,
1303 base, fn, trim, flags, cb_data);
1304 } else if (loose_dir) {
1305 sort_ref_dir(loose_dir);
1306 retval = do_for_each_ref_in_dir(
1307 loose_dir, 0,
1308 base, fn, trim, flags, cb_data);
1311 return retval;
1314 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
1316 unsigned char sha1[20];
1317 int flag;
1319 if (submodule) {
1320 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
1321 return fn("HEAD", sha1, 0, cb_data);
1323 return 0;
1326 if (!read_ref_full("HEAD", sha1, 1, &flag))
1327 return fn("HEAD", sha1, flag, cb_data);
1329 return 0;
1332 int head_ref(each_ref_fn fn, void *cb_data)
1334 return do_head_ref(NULL, fn, cb_data);
1337 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1339 return do_head_ref(submodule, fn, cb_data);
1342 int for_each_ref(each_ref_fn fn, void *cb_data)
1344 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
1347 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1349 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
1352 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1354 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
1357 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1358 each_ref_fn fn, void *cb_data)
1360 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
1363 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
1365 return for_each_ref_in("refs/tags/", fn, cb_data);
1368 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1370 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1373 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
1375 return for_each_ref_in("refs/heads/", fn, cb_data);
1378 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1380 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1383 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
1385 return for_each_ref_in("refs/remotes/", fn, cb_data);
1388 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1390 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1393 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1395 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
1398 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1400 struct strbuf buf = STRBUF_INIT;
1401 int ret = 0;
1402 unsigned char sha1[20];
1403 int flag;
1405 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
1406 if (!read_ref_full(buf.buf, sha1, 1, &flag))
1407 ret = fn(buf.buf, sha1, flag, cb_data);
1408 strbuf_release(&buf);
1410 return ret;
1413 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1415 struct strbuf buf = STRBUF_INIT;
1416 int ret;
1417 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1418 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
1419 strbuf_release(&buf);
1420 return ret;
1423 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1424 const char *prefix, void *cb_data)
1426 struct strbuf real_pattern = STRBUF_INIT;
1427 struct ref_filter filter;
1428 int ret;
1430 if (!prefix && prefixcmp(pattern, "refs/"))
1431 strbuf_addstr(&real_pattern, "refs/");
1432 else if (prefix)
1433 strbuf_addstr(&real_pattern, prefix);
1434 strbuf_addstr(&real_pattern, pattern);
1436 if (!has_glob_specials(pattern)) {
1437 /* Append implied '/' '*' if not present. */
1438 if (real_pattern.buf[real_pattern.len - 1] != '/')
1439 strbuf_addch(&real_pattern, '/');
1440 /* No need to check for '*', there is none. */
1441 strbuf_addch(&real_pattern, '*');
1444 filter.pattern = real_pattern.buf;
1445 filter.fn = fn;
1446 filter.cb_data = cb_data;
1447 ret = for_each_ref(filter_refs, &filter);
1449 strbuf_release(&real_pattern);
1450 return ret;
1453 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1455 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1458 int for_each_rawref(each_ref_fn fn, void *cb_data)
1460 return do_for_each_ref(NULL, "", fn, 0,
1461 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1464 const char *prettify_refname(const char *name)
1466 return name + (
1467 !prefixcmp(name, "refs/heads/") ? 11 :
1468 !prefixcmp(name, "refs/tags/") ? 10 :
1469 !prefixcmp(name, "refs/remotes/") ? 13 :
1473 const char *ref_rev_parse_rules[] = {
1474 "%.*s",
1475 "refs/%.*s",
1476 "refs/tags/%.*s",
1477 "refs/heads/%.*s",
1478 "refs/remotes/%.*s",
1479 "refs/remotes/%.*s/HEAD",
1480 NULL
1483 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1485 const char **p;
1486 const int abbrev_name_len = strlen(abbrev_name);
1488 for (p = rules; *p; p++) {
1489 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1490 return 1;
1494 return 0;
1497 static struct ref_lock *verify_lock(struct ref_lock *lock,
1498 const unsigned char *old_sha1, int mustexist)
1500 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
1501 error("Can't verify ref %s", lock->ref_name);
1502 unlock_ref(lock);
1503 return NULL;
1505 if (hashcmp(lock->old_sha1, old_sha1)) {
1506 error("Ref %s is at %s but expected %s", lock->ref_name,
1507 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1508 unlock_ref(lock);
1509 return NULL;
1511 return lock;
1514 static int remove_empty_directories(const char *file)
1516 /* we want to create a file but there is a directory there;
1517 * if that is an empty directory (or a directory that contains
1518 * only empty directories), remove them.
1520 struct strbuf path;
1521 int result;
1523 strbuf_init(&path, 20);
1524 strbuf_addstr(&path, file);
1526 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1528 strbuf_release(&path);
1530 return result;
1534 * *string and *len will only be substituted, and *string returned (for
1535 * later free()ing) if the string passed in is a magic short-hand form
1536 * to name a branch.
1538 static char *substitute_branch_name(const char **string, int *len)
1540 struct strbuf buf = STRBUF_INIT;
1541 int ret = interpret_branch_name(*string, &buf);
1543 if (ret == *len) {
1544 size_t size;
1545 *string = strbuf_detach(&buf, &size);
1546 *len = size;
1547 return (char *)*string;
1550 return NULL;
1553 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1555 char *last_branch = substitute_branch_name(&str, &len);
1556 const char **p, *r;
1557 int refs_found = 0;
1559 *ref = NULL;
1560 for (p = ref_rev_parse_rules; *p; p++) {
1561 char fullref[PATH_MAX];
1562 unsigned char sha1_from_ref[20];
1563 unsigned char *this_result;
1564 int flag;
1566 this_result = refs_found ? sha1_from_ref : sha1;
1567 mksnpath(fullref, sizeof(fullref), *p, len, str);
1568 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
1569 if (r) {
1570 if (!refs_found++)
1571 *ref = xstrdup(r);
1572 if (!warn_ambiguous_refs)
1573 break;
1574 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
1575 warning("ignoring dangling symref %s.", fullref);
1576 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1577 warning("ignoring broken ref %s.", fullref);
1580 free(last_branch);
1581 return refs_found;
1584 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1586 char *last_branch = substitute_branch_name(&str, &len);
1587 const char **p;
1588 int logs_found = 0;
1590 *log = NULL;
1591 for (p = ref_rev_parse_rules; *p; p++) {
1592 struct stat st;
1593 unsigned char hash[20];
1594 char path[PATH_MAX];
1595 const char *ref, *it;
1597 mksnpath(path, sizeof(path), *p, len, str);
1598 ref = resolve_ref_unsafe(path, hash, 1, NULL);
1599 if (!ref)
1600 continue;
1601 if (!stat(git_path("logs/%s", path), &st) &&
1602 S_ISREG(st.st_mode))
1603 it = path;
1604 else if (strcmp(ref, path) &&
1605 !stat(git_path("logs/%s", ref), &st) &&
1606 S_ISREG(st.st_mode))
1607 it = ref;
1608 else
1609 continue;
1610 if (!logs_found++) {
1611 *log = xstrdup(it);
1612 hashcpy(sha1, hash);
1614 if (!warn_ambiguous_refs)
1615 break;
1617 free(last_branch);
1618 return logs_found;
1621 static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1622 const unsigned char *old_sha1,
1623 int flags, int *type_p)
1625 char *ref_file;
1626 const char *orig_refname = refname;
1627 struct ref_lock *lock;
1628 int last_errno = 0;
1629 int type, lflags;
1630 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1631 int missing = 0;
1633 lock = xcalloc(1, sizeof(struct ref_lock));
1634 lock->lock_fd = -1;
1636 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
1637 if (!refname && errno == EISDIR) {
1638 /* we are trying to lock foo but we used to
1639 * have foo/bar which now does not exist;
1640 * it is normal for the empty directory 'foo'
1641 * to remain.
1643 ref_file = git_path("%s", orig_refname);
1644 if (remove_empty_directories(ref_file)) {
1645 last_errno = errno;
1646 error("there are still refs under '%s'", orig_refname);
1647 goto error_return;
1649 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
1651 if (type_p)
1652 *type_p = type;
1653 if (!refname) {
1654 last_errno = errno;
1655 error("unable to resolve reference %s: %s",
1656 orig_refname, strerror(errno));
1657 goto error_return;
1659 missing = is_null_sha1(lock->old_sha1);
1660 /* When the ref did not exist and we are creating it,
1661 * make sure there is no existing ref that is packed
1662 * whose name begins with our refname, nor a ref whose
1663 * name is a proper prefix of our refname.
1665 if (missing &&
1666 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
1667 last_errno = ENOTDIR;
1668 goto error_return;
1671 lock->lk = xcalloc(1, sizeof(struct lock_file));
1673 lflags = LOCK_DIE_ON_ERROR;
1674 if (flags & REF_NODEREF) {
1675 refname = orig_refname;
1676 lflags |= LOCK_NODEREF;
1678 lock->ref_name = xstrdup(refname);
1679 lock->orig_ref_name = xstrdup(orig_refname);
1680 ref_file = git_path("%s", refname);
1681 if (missing)
1682 lock->force_write = 1;
1683 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1684 lock->force_write = 1;
1686 if (safe_create_leading_directories(ref_file)) {
1687 last_errno = errno;
1688 error("unable to create directory for %s", ref_file);
1689 goto error_return;
1692 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1693 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1695 error_return:
1696 unlock_ref(lock);
1697 errno = last_errno;
1698 return NULL;
1701 struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
1703 char refpath[PATH_MAX];
1704 if (check_refname_format(refname, 0))
1705 return NULL;
1706 strcpy(refpath, mkpath("refs/%s", refname));
1707 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1710 struct ref_lock *lock_any_ref_for_update(const char *refname,
1711 const unsigned char *old_sha1, int flags)
1713 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
1714 return NULL;
1715 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
1718 struct repack_without_ref_sb {
1719 const char *refname;
1720 int fd;
1723 static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,
1724 int flags, void *cb_data)
1726 struct repack_without_ref_sb *data = cb_data;
1727 char line[PATH_MAX + 100];
1728 int len;
1730 if (!strcmp(data->refname, refname))
1731 return 0;
1732 len = snprintf(line, sizeof(line), "%s %s\n",
1733 sha1_to_hex(sha1), refname);
1734 /* this should not happen but just being defensive */
1735 if (len > sizeof(line))
1736 die("too long a refname '%s'", refname);
1737 write_or_die(data->fd, line, len);
1738 return 0;
1741 static struct lock_file packlock;
1743 static int repack_without_ref(const char *refname)
1745 struct repack_without_ref_sb data;
1746 struct ref_cache *refs = get_ref_cache(NULL);
1747 struct ref_dir *packed = get_packed_refs(refs);
1748 if (find_ref(packed, refname) == NULL)
1749 return 0;
1750 data.refname = refname;
1751 data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1752 if (data.fd < 0) {
1753 unable_to_lock_error(git_path("packed-refs"), errno);
1754 return error("cannot delete '%s' from packed refs", refname);
1756 clear_packed_ref_cache(refs);
1757 packed = get_packed_refs(refs);
1758 do_for_each_ref_in_dir(packed, 0, "", repack_without_ref_fn, 0, 0, &data);
1759 return commit_lock_file(&packlock);
1762 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1764 struct ref_lock *lock;
1765 int err, i = 0, ret = 0, flag = 0;
1767 lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);
1768 if (!lock)
1769 return 1;
1770 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1771 /* loose */
1772 i = strlen(lock->lk->filename) - 5; /* .lock */
1773 lock->lk->filename[i] = 0;
1774 err = unlink_or_warn(lock->lk->filename);
1775 if (err && errno != ENOENT)
1776 ret = 1;
1778 lock->lk->filename[i] = '.';
1780 /* removing the loose one could have resurrected an earlier
1781 * packed one. Also, if it was not loose we need to repack
1782 * without it.
1784 ret |= repack_without_ref(lock->ref_name);
1786 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1787 invalidate_ref_cache(NULL);
1788 unlock_ref(lock);
1789 return ret;
1793 * People using contrib's git-new-workdir have .git/logs/refs ->
1794 * /some/other/path/.git/logs/refs, and that may live on another device.
1796 * IOW, to avoid cross device rename errors, the temporary renamed log must
1797 * live into logs/refs.
1799 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1801 int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
1803 unsigned char sha1[20], orig_sha1[20];
1804 int flag = 0, logmoved = 0;
1805 struct ref_lock *lock;
1806 struct stat loginfo;
1807 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
1808 const char *symref = NULL;
1809 struct ref_cache *refs = get_ref_cache(NULL);
1811 if (log && S_ISLNK(loginfo.st_mode))
1812 return error("reflog for %s is a symlink", oldrefname);
1814 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
1815 if (flag & REF_ISSYMREF)
1816 return error("refname %s is a symbolic ref, renaming it is not supported",
1817 oldrefname);
1818 if (!symref)
1819 return error("refname %s not found", oldrefname);
1821 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
1822 return 1;
1824 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
1825 return 1;
1827 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
1828 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1829 oldrefname, strerror(errno));
1831 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
1832 error("unable to delete old %s", oldrefname);
1833 goto rollback;
1836 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
1837 delete_ref(newrefname, sha1, REF_NODEREF)) {
1838 if (errno==EISDIR) {
1839 if (remove_empty_directories(git_path("%s", newrefname))) {
1840 error("Directory not empty: %s", newrefname);
1841 goto rollback;
1843 } else {
1844 error("unable to delete existing %s", newrefname);
1845 goto rollback;
1849 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1850 error("unable to create directory for %s", newrefname);
1851 goto rollback;
1854 retry:
1855 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
1856 if (errno==EISDIR || errno==ENOTDIR) {
1858 * rename(a, b) when b is an existing
1859 * directory ought to result in ISDIR, but
1860 * Solaris 5.8 gives ENOTDIR. Sheesh.
1862 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1863 error("Directory not empty: logs/%s", newrefname);
1864 goto rollback;
1866 goto retry;
1867 } else {
1868 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1869 newrefname, strerror(errno));
1870 goto rollback;
1873 logmoved = log;
1875 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
1876 if (!lock) {
1877 error("unable to lock %s for update", newrefname);
1878 goto rollback;
1880 lock->force_write = 1;
1881 hashcpy(lock->old_sha1, orig_sha1);
1882 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1883 error("unable to write current sha1 into %s", newrefname);
1884 goto rollback;
1887 return 0;
1889 rollback:
1890 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
1891 if (!lock) {
1892 error("unable to lock %s for rollback", oldrefname);
1893 goto rollbacklog;
1896 lock->force_write = 1;
1897 flag = log_all_ref_updates;
1898 log_all_ref_updates = 0;
1899 if (write_ref_sha1(lock, orig_sha1, NULL))
1900 error("unable to write current sha1 into %s", oldrefname);
1901 log_all_ref_updates = flag;
1903 rollbacklog:
1904 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
1905 error("unable to restore logfile %s from %s: %s",
1906 oldrefname, newrefname, strerror(errno));
1907 if (!logmoved && log &&
1908 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
1909 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1910 oldrefname, strerror(errno));
1912 return 1;
1915 int close_ref(struct ref_lock *lock)
1917 if (close_lock_file(lock->lk))
1918 return -1;
1919 lock->lock_fd = -1;
1920 return 0;
1923 int commit_ref(struct ref_lock *lock)
1925 if (commit_lock_file(lock->lk))
1926 return -1;
1927 lock->lock_fd = -1;
1928 return 0;
1931 void unlock_ref(struct ref_lock *lock)
1933 /* Do not free lock->lk -- atexit() still looks at them */
1934 if (lock->lk)
1935 rollback_lock_file(lock->lk);
1936 free(lock->ref_name);
1937 free(lock->orig_ref_name);
1938 free(lock);
1942 * copy the reflog message msg to buf, which has been allocated sufficiently
1943 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1944 * because reflog file is one line per entry.
1946 static int copy_msg(char *buf, const char *msg)
1948 char *cp = buf;
1949 char c;
1950 int wasspace = 1;
1952 *cp++ = '\t';
1953 while ((c = *msg++)) {
1954 if (wasspace && isspace(c))
1955 continue;
1956 wasspace = isspace(c);
1957 if (wasspace)
1958 c = ' ';
1959 *cp++ = c;
1961 while (buf < cp && isspace(cp[-1]))
1962 cp--;
1963 *cp++ = '\n';
1964 return cp - buf;
1967 int log_ref_setup(const char *refname, char *logfile, int bufsize)
1969 int logfd, oflags = O_APPEND | O_WRONLY;
1971 git_snpath(logfile, bufsize, "logs/%s", refname);
1972 if (log_all_ref_updates &&
1973 (!prefixcmp(refname, "refs/heads/") ||
1974 !prefixcmp(refname, "refs/remotes/") ||
1975 !prefixcmp(refname, "refs/notes/") ||
1976 !strcmp(refname, "HEAD"))) {
1977 if (safe_create_leading_directories(logfile) < 0)
1978 return error("unable to create directory for %s",
1979 logfile);
1980 oflags |= O_CREAT;
1983 logfd = open(logfile, oflags, 0666);
1984 if (logfd < 0) {
1985 if (!(oflags & O_CREAT) && errno == ENOENT)
1986 return 0;
1988 if ((oflags & O_CREAT) && errno == EISDIR) {
1989 if (remove_empty_directories(logfile)) {
1990 return error("There are still logs under '%s'",
1991 logfile);
1993 logfd = open(logfile, oflags, 0666);
1996 if (logfd < 0)
1997 return error("Unable to append to %s: %s",
1998 logfile, strerror(errno));
2001 adjust_shared_perm(logfile);
2002 close(logfd);
2003 return 0;
2006 static int log_ref_write(const char *refname, const unsigned char *old_sha1,
2007 const unsigned char *new_sha1, const char *msg)
2009 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
2010 unsigned maxlen, len;
2011 int msglen;
2012 char log_file[PATH_MAX];
2013 char *logrec;
2014 const char *committer;
2016 if (log_all_ref_updates < 0)
2017 log_all_ref_updates = !is_bare_repository();
2019 result = log_ref_setup(refname, log_file, sizeof(log_file));
2020 if (result)
2021 return result;
2023 logfd = open(log_file, oflags);
2024 if (logfd < 0)
2025 return 0;
2026 msglen = msg ? strlen(msg) : 0;
2027 committer = git_committer_info(0);
2028 maxlen = strlen(committer) + msglen + 100;
2029 logrec = xmalloc(maxlen);
2030 len = sprintf(logrec, "%s %s %s\n",
2031 sha1_to_hex(old_sha1),
2032 sha1_to_hex(new_sha1),
2033 committer);
2034 if (msglen)
2035 len += copy_msg(logrec + len - 1, msg) - 1;
2036 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
2037 free(logrec);
2038 if (close(logfd) != 0 || written != len)
2039 return error("Unable to append to %s", log_file);
2040 return 0;
2043 static int is_branch(const char *refname)
2045 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
2048 int write_ref_sha1(struct ref_lock *lock,
2049 const unsigned char *sha1, const char *logmsg)
2051 static char term = '\n';
2052 struct object *o;
2054 if (!lock)
2055 return -1;
2056 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
2057 unlock_ref(lock);
2058 return 0;
2060 o = parse_object(sha1);
2061 if (!o) {
2062 error("Trying to write ref %s with nonexistent object %s",
2063 lock->ref_name, sha1_to_hex(sha1));
2064 unlock_ref(lock);
2065 return -1;
2067 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
2068 error("Trying to write non-commit object %s to branch %s",
2069 sha1_to_hex(sha1), lock->ref_name);
2070 unlock_ref(lock);
2071 return -1;
2073 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
2074 write_in_full(lock->lock_fd, &term, 1) != 1
2075 || close_ref(lock) < 0) {
2076 error("Couldn't write %s", lock->lk->filename);
2077 unlock_ref(lock);
2078 return -1;
2080 clear_loose_ref_cache(get_ref_cache(NULL));
2081 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
2082 (strcmp(lock->ref_name, lock->orig_ref_name) &&
2083 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
2084 unlock_ref(lock);
2085 return -1;
2087 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
2089 * Special hack: If a branch is updated directly and HEAD
2090 * points to it (may happen on the remote side of a push
2091 * for example) then logically the HEAD reflog should be
2092 * updated too.
2093 * A generic solution implies reverse symref information,
2094 * but finding all symrefs pointing to the given branch
2095 * would be rather costly for this rare event (the direct
2096 * update of a branch) to be worth it. So let's cheat and
2097 * check with HEAD only which should cover 99% of all usage
2098 * scenarios (even 100% of the default ones).
2100 unsigned char head_sha1[20];
2101 int head_flag;
2102 const char *head_ref;
2103 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
2104 if (head_ref && (head_flag & REF_ISSYMREF) &&
2105 !strcmp(head_ref, lock->ref_name))
2106 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
2108 if (commit_ref(lock)) {
2109 error("Couldn't set %s", lock->ref_name);
2110 unlock_ref(lock);
2111 return -1;
2113 unlock_ref(lock);
2114 return 0;
2117 int create_symref(const char *ref_target, const char *refs_heads_master,
2118 const char *logmsg)
2120 const char *lockpath;
2121 char ref[1000];
2122 int fd, len, written;
2123 char *git_HEAD = git_pathdup("%s", ref_target);
2124 unsigned char old_sha1[20], new_sha1[20];
2126 if (logmsg && read_ref(ref_target, old_sha1))
2127 hashclr(old_sha1);
2129 if (safe_create_leading_directories(git_HEAD) < 0)
2130 return error("unable to create directory for %s", git_HEAD);
2132 #ifndef NO_SYMLINK_HEAD
2133 if (prefer_symlink_refs) {
2134 unlink(git_HEAD);
2135 if (!symlink(refs_heads_master, git_HEAD))
2136 goto done;
2137 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
2139 #endif
2141 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
2142 if (sizeof(ref) <= len) {
2143 error("refname too long: %s", refs_heads_master);
2144 goto error_free_return;
2146 lockpath = mkpath("%s.lock", git_HEAD);
2147 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
2148 if (fd < 0) {
2149 error("Unable to open %s for writing", lockpath);
2150 goto error_free_return;
2152 written = write_in_full(fd, ref, len);
2153 if (close(fd) != 0 || written != len) {
2154 error("Unable to write to %s", lockpath);
2155 goto error_unlink_return;
2157 if (rename(lockpath, git_HEAD) < 0) {
2158 error("Unable to create %s", git_HEAD);
2159 goto error_unlink_return;
2161 if (adjust_shared_perm(git_HEAD)) {
2162 error("Unable to fix permissions on %s", lockpath);
2163 error_unlink_return:
2164 unlink_or_warn(lockpath);
2165 error_free_return:
2166 free(git_HEAD);
2167 return -1;
2170 #ifndef NO_SYMLINK_HEAD
2171 done:
2172 #endif
2173 if (logmsg && !read_ref(refs_heads_master, new_sha1))
2174 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
2176 free(git_HEAD);
2177 return 0;
2180 static char *ref_msg(const char *line, const char *endp)
2182 const char *ep;
2183 line += 82;
2184 ep = memchr(line, '\n', endp - line);
2185 if (!ep)
2186 ep = endp;
2187 return xmemdupz(line, ep - line);
2190 int read_ref_at(const char *refname, unsigned long at_time, int cnt,
2191 unsigned char *sha1, char **msg,
2192 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
2194 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
2195 char *tz_c;
2196 int logfd, tz, reccnt = 0;
2197 struct stat st;
2198 unsigned long date;
2199 unsigned char logged_sha1[20];
2200 void *log_mapped;
2201 size_t mapsz;
2203 logfile = git_path("logs/%s", refname);
2204 logfd = open(logfile, O_RDONLY, 0);
2205 if (logfd < 0)
2206 die_errno("Unable to read log '%s'", logfile);
2207 fstat(logfd, &st);
2208 if (!st.st_size)
2209 die("Log %s is empty.", logfile);
2210 mapsz = xsize_t(st.st_size);
2211 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
2212 logdata = log_mapped;
2213 close(logfd);
2215 lastrec = NULL;
2216 rec = logend = logdata + st.st_size;
2217 while (logdata < rec) {
2218 reccnt++;
2219 if (logdata < rec && *(rec-1) == '\n')
2220 rec--;
2221 lastgt = NULL;
2222 while (logdata < rec && *(rec-1) != '\n') {
2223 rec--;
2224 if (*rec == '>')
2225 lastgt = rec;
2227 if (!lastgt)
2228 die("Log %s is corrupt.", logfile);
2229 date = strtoul(lastgt + 1, &tz_c, 10);
2230 if (date <= at_time || cnt == 0) {
2231 tz = strtoul(tz_c, NULL, 10);
2232 if (msg)
2233 *msg = ref_msg(rec, logend);
2234 if (cutoff_time)
2235 *cutoff_time = date;
2236 if (cutoff_tz)
2237 *cutoff_tz = tz;
2238 if (cutoff_cnt)
2239 *cutoff_cnt = reccnt - 1;
2240 if (lastrec) {
2241 if (get_sha1_hex(lastrec, logged_sha1))
2242 die("Log %s is corrupt.", logfile);
2243 if (get_sha1_hex(rec + 41, sha1))
2244 die("Log %s is corrupt.", logfile);
2245 if (hashcmp(logged_sha1, sha1)) {
2246 warning("Log %s has gap after %s.",
2247 logfile, show_date(date, tz, DATE_RFC2822));
2250 else if (date == at_time) {
2251 if (get_sha1_hex(rec + 41, sha1))
2252 die("Log %s is corrupt.", logfile);
2254 else {
2255 if (get_sha1_hex(rec + 41, logged_sha1))
2256 die("Log %s is corrupt.", logfile);
2257 if (hashcmp(logged_sha1, sha1)) {
2258 warning("Log %s unexpectedly ended on %s.",
2259 logfile, show_date(date, tz, DATE_RFC2822));
2262 munmap(log_mapped, mapsz);
2263 return 0;
2265 lastrec = rec;
2266 if (cnt > 0)
2267 cnt--;
2270 rec = logdata;
2271 while (rec < logend && *rec != '>' && *rec != '\n')
2272 rec++;
2273 if (rec == logend || *rec == '\n')
2274 die("Log %s is corrupt.", logfile);
2275 date = strtoul(rec + 1, &tz_c, 10);
2276 tz = strtoul(tz_c, NULL, 10);
2277 if (get_sha1_hex(logdata, sha1))
2278 die("Log %s is corrupt.", logfile);
2279 if (is_null_sha1(sha1)) {
2280 if (get_sha1_hex(logdata + 41, sha1))
2281 die("Log %s is corrupt.", logfile);
2283 if (msg)
2284 *msg = ref_msg(logdata, logend);
2285 munmap(log_mapped, mapsz);
2287 if (cutoff_time)
2288 *cutoff_time = date;
2289 if (cutoff_tz)
2290 *cutoff_tz = tz;
2291 if (cutoff_cnt)
2292 *cutoff_cnt = reccnt;
2293 return 1;
2296 int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
2298 const char *logfile;
2299 FILE *logfp;
2300 struct strbuf sb = STRBUF_INIT;
2301 int ret = 0;
2303 logfile = git_path("logs/%s", refname);
2304 logfp = fopen(logfile, "r");
2305 if (!logfp)
2306 return -1;
2308 if (ofs) {
2309 struct stat statbuf;
2310 if (fstat(fileno(logfp), &statbuf) ||
2311 statbuf.st_size < ofs ||
2312 fseek(logfp, -ofs, SEEK_END) ||
2313 strbuf_getwholeline(&sb, logfp, '\n')) {
2314 fclose(logfp);
2315 strbuf_release(&sb);
2316 return -1;
2320 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
2321 unsigned char osha1[20], nsha1[20];
2322 char *email_end, *message;
2323 unsigned long timestamp;
2324 int tz;
2326 /* old SP new SP name <email> SP time TAB msg LF */
2327 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
2328 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
2329 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
2330 !(email_end = strchr(sb.buf + 82, '>')) ||
2331 email_end[1] != ' ' ||
2332 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
2333 !message || message[0] != ' ' ||
2334 (message[1] != '+' && message[1] != '-') ||
2335 !isdigit(message[2]) || !isdigit(message[3]) ||
2336 !isdigit(message[4]) || !isdigit(message[5]))
2337 continue; /* corrupt? */
2338 email_end[1] = '\0';
2339 tz = strtol(message + 1, NULL, 10);
2340 if (message[6] != '\t')
2341 message += 6;
2342 else
2343 message += 7;
2344 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
2345 cb_data);
2346 if (ret)
2347 break;
2349 fclose(logfp);
2350 strbuf_release(&sb);
2351 return ret;
2354 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
2356 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
2360 * Call fn for each reflog in the namespace indicated by name. name
2361 * must be empty or end with '/'. Name will be used as a scratch
2362 * space, but its contents will be restored before return.
2364 static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)
2366 DIR *d = opendir(git_path("logs/%s", name->buf));
2367 int retval = 0;
2368 struct dirent *de;
2369 int oldlen = name->len;
2371 if (!d)
2372 return name->len ? errno : 0;
2374 while ((de = readdir(d)) != NULL) {
2375 struct stat st;
2377 if (de->d_name[0] == '.')
2378 continue;
2379 if (has_extension(de->d_name, ".lock"))
2380 continue;
2381 strbuf_addstr(name, de->d_name);
2382 if (stat(git_path("logs/%s", name->buf), &st) < 0) {
2383 ; /* silently ignore */
2384 } else {
2385 if (S_ISDIR(st.st_mode)) {
2386 strbuf_addch(name, '/');
2387 retval = do_for_each_reflog(name, fn, cb_data);
2388 } else {
2389 unsigned char sha1[20];
2390 if (read_ref_full(name->buf, sha1, 0, NULL))
2391 retval = error("bad ref for %s", name->buf);
2392 else
2393 retval = fn(name->buf, sha1, 0, cb_data);
2395 if (retval)
2396 break;
2398 strbuf_setlen(name, oldlen);
2400 closedir(d);
2401 return retval;
2404 int for_each_reflog(each_ref_fn fn, void *cb_data)
2406 int retval;
2407 struct strbuf name;
2408 strbuf_init(&name, PATH_MAX);
2409 retval = do_for_each_reflog(&name, fn, cb_data);
2410 strbuf_release(&name);
2411 return retval;
2414 int update_ref(const char *action, const char *refname,
2415 const unsigned char *sha1, const unsigned char *oldval,
2416 int flags, enum action_on_err onerr)
2418 static struct ref_lock *lock;
2419 lock = lock_any_ref_for_update(refname, oldval, flags);
2420 if (!lock) {
2421 const char *str = "Cannot lock the ref '%s'.";
2422 switch (onerr) {
2423 case MSG_ON_ERR: error(str, refname); break;
2424 case DIE_ON_ERR: die(str, refname); break;
2425 case QUIET_ON_ERR: break;
2427 return 1;
2429 if (write_ref_sha1(lock, sha1, action) < 0) {
2430 const char *str = "Cannot update the ref '%s'.";
2431 switch (onerr) {
2432 case MSG_ON_ERR: error(str, refname); break;
2433 case DIE_ON_ERR: die(str, refname); break;
2434 case QUIET_ON_ERR: break;
2436 return 1;
2438 return 0;
2441 struct ref *find_ref_by_name(const struct ref *list, const char *name)
2443 for ( ; list; list = list->next)
2444 if (!strcmp(list->name, name))
2445 return (struct ref *)list;
2446 return NULL;
2450 * generate a format suitable for scanf from a ref_rev_parse_rules
2451 * rule, that is replace the "%.*s" spec with a "%s" spec
2453 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2455 char *spec;
2457 spec = strstr(rule, "%.*s");
2458 if (!spec || strstr(spec + 4, "%.*s"))
2459 die("invalid rule in ref_rev_parse_rules: %s", rule);
2461 /* copy all until spec */
2462 strncpy(scanf_fmt, rule, spec - rule);
2463 scanf_fmt[spec - rule] = '\0';
2464 /* copy new spec */
2465 strcat(scanf_fmt, "%s");
2466 /* copy remaining rule */
2467 strcat(scanf_fmt, spec + 4);
2469 return;
2472 char *shorten_unambiguous_ref(const char *refname, int strict)
2474 int i;
2475 static char **scanf_fmts;
2476 static int nr_rules;
2477 char *short_name;
2479 /* pre generate scanf formats from ref_rev_parse_rules[] */
2480 if (!nr_rules) {
2481 size_t total_len = 0;
2483 /* the rule list is NULL terminated, count them first */
2484 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2485 /* no +1 because strlen("%s") < strlen("%.*s") */
2486 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2488 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2490 total_len = 0;
2491 for (i = 0; i < nr_rules; i++) {
2492 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2493 + total_len;
2494 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2495 total_len += strlen(ref_rev_parse_rules[i]);
2499 /* bail out if there are no rules */
2500 if (!nr_rules)
2501 return xstrdup(refname);
2503 /* buffer for scanf result, at most refname must fit */
2504 short_name = xstrdup(refname);
2506 /* skip first rule, it will always match */
2507 for (i = nr_rules - 1; i > 0 ; --i) {
2508 int j;
2509 int rules_to_fail = i;
2510 int short_name_len;
2512 if (1 != sscanf(refname, scanf_fmts[i], short_name))
2513 continue;
2515 short_name_len = strlen(short_name);
2518 * in strict mode, all (except the matched one) rules
2519 * must fail to resolve to a valid non-ambiguous ref
2521 if (strict)
2522 rules_to_fail = nr_rules;
2525 * check if the short name resolves to a valid ref,
2526 * but use only rules prior to the matched one
2528 for (j = 0; j < rules_to_fail; j++) {
2529 const char *rule = ref_rev_parse_rules[j];
2530 char refname[PATH_MAX];
2532 /* skip matched rule */
2533 if (i == j)
2534 continue;
2537 * the short name is ambiguous, if it resolves
2538 * (with this previous rule) to a valid ref
2539 * read_ref() returns 0 on success
2541 mksnpath(refname, sizeof(refname),
2542 rule, short_name_len, short_name);
2543 if (ref_exists(refname))
2544 break;
2548 * short name is non-ambiguous if all previous rules
2549 * haven't resolved to a valid ref
2551 if (j == rules_to_fail)
2552 return short_name;
2555 free(short_name);
2556 return xstrdup(refname);
2559 static struct string_list *hide_refs;
2561 int parse_hide_refs_config(const char *var, const char *value, const char *section)
2563 if (!strcmp("transfer.hiderefs", var) ||
2564 /* NEEDSWORK: use parse_config_key() once both are merged */
2565 (!prefixcmp(var, section) && var[strlen(section)] == '.' &&
2566 !strcmp(var + strlen(section), ".hiderefs"))) {
2567 char *ref;
2568 int len;
2570 if (!value)
2571 return config_error_nonbool(var);
2572 ref = xstrdup(value);
2573 len = strlen(ref);
2574 while (len && ref[len - 1] == '/')
2575 ref[--len] = '\0';
2576 if (!hide_refs) {
2577 hide_refs = xcalloc(1, sizeof(*hide_refs));
2578 hide_refs->strdup_strings = 1;
2580 string_list_append(hide_refs, ref);
2582 return 0;
2585 int ref_is_hidden(const char *refname)
2587 struct string_list_item *item;
2589 if (!hide_refs)
2590 return 0;
2591 for_each_string_list_item(item, hide_refs) {
2592 int len;
2593 if (prefixcmp(refname, item->string))
2594 continue;
2595 len = strlen(item->string);
2596 if (!refname[len] || refname[len] == '/')
2597 return 1;
2599 return 0;