Merge branch 'master' of git://git.kernel.org/pub/scm/git/git
[git/jnareb-git.git] / refs.c
blobde2d8eb866062649a0d0f23a77e350bca1a182cd
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;
807 * Read f, which is a packed-refs file, into dir.
809 * A comment line of the form "# pack-refs with: " may contain zero or
810 * more traits. We interpret the traits as follows:
812 * No traits:
814 * Probably no references are peeled. But if the file contains a
815 * peeled value for a reference, we will use it.
817 * peeled:
819 * References under "refs/tags/", if they *can* be peeled, *are*
820 * peeled in this file. References outside of "refs/tags/" are
821 * probably not peeled even if they could have been, but if we find
822 * a peeled value for such a reference we will use it.
824 * fully-peeled:
826 * All references in the file that can be peeled are peeled.
827 * Inversely (and this is more important), any references in the
828 * file for which no peeled value is recorded is not peelable. This
829 * trait should typically be written alongside "peeled" for
830 * compatibility with older clients, but we do not require it
831 * (i.e., "peeled" is a no-op if "fully-peeled" is set).
833 static void read_packed_refs(FILE *f, struct ref_dir *dir)
835 struct ref_entry *last = NULL;
836 char refline[PATH_MAX];
837 enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE;
839 while (fgets(refline, sizeof(refline), f)) {
840 unsigned char sha1[20];
841 const char *refname;
842 static const char header[] = "# pack-refs with:";
844 if (!strncmp(refline, header, sizeof(header)-1)) {
845 const char *traits = refline + sizeof(header) - 1;
846 if (strstr(traits, " fully-peeled "))
847 peeled = PEELED_FULLY;
848 else if (strstr(traits, " peeled "))
849 peeled = PEELED_TAGS;
850 /* perhaps other traits later as well */
851 continue;
854 refname = parse_ref_line(refline, sha1);
855 if (refname) {
856 last = create_ref_entry(refname, sha1, REF_ISPACKED, 1);
857 if (peeled == PEELED_FULLY ||
858 (peeled == PEELED_TAGS && !prefixcmp(refname, "refs/tags/")))
859 last->flag |= REF_KNOWS_PEELED;
860 add_ref(dir, last);
861 continue;
863 if (last &&
864 refline[0] == '^' &&
865 strlen(refline) == 42 &&
866 refline[41] == '\n' &&
867 !get_sha1_hex(refline + 1, sha1)) {
868 hashcpy(last->u.value.peeled, sha1);
870 * Regardless of what the file header said,
871 * we definitely know the value of *this*
872 * reference:
874 last->flag |= REF_KNOWS_PEELED;
879 static struct ref_dir *get_packed_refs(struct ref_cache *refs)
881 if (!refs->packed) {
882 const char *packed_refs_file;
883 FILE *f;
885 refs->packed = create_dir_entry(refs, "", 0, 0);
886 if (*refs->name)
887 packed_refs_file = git_path_submodule(refs->name, "packed-refs");
888 else
889 packed_refs_file = git_path("packed-refs");
890 f = fopen(packed_refs_file, "r");
891 if (f) {
892 read_packed_refs(f, get_ref_dir(refs->packed));
893 fclose(f);
896 return get_ref_dir(refs->packed);
899 void add_packed_ref(const char *refname, const unsigned char *sha1)
901 add_ref(get_packed_refs(get_ref_cache(NULL)),
902 create_ref_entry(refname, sha1, REF_ISPACKED, 1));
906 * Read the loose references from the namespace dirname into dir
907 * (without recursing). dirname must end with '/'. dir must be the
908 * directory entry corresponding to dirname.
910 static void read_loose_refs(const char *dirname, struct ref_dir *dir)
912 struct ref_cache *refs = dir->ref_cache;
913 DIR *d;
914 const char *path;
915 struct dirent *de;
916 int dirnamelen = strlen(dirname);
917 struct strbuf refname;
919 if (*refs->name)
920 path = git_path_submodule(refs->name, "%s", dirname);
921 else
922 path = git_path("%s", dirname);
924 d = opendir(path);
925 if (!d)
926 return;
928 strbuf_init(&refname, dirnamelen + 257);
929 strbuf_add(&refname, dirname, dirnamelen);
931 while ((de = readdir(d)) != NULL) {
932 unsigned char sha1[20];
933 struct stat st;
934 int flag;
935 const char *refdir;
937 if (de->d_name[0] == '.')
938 continue;
939 if (has_extension(de->d_name, ".lock"))
940 continue;
941 strbuf_addstr(&refname, de->d_name);
942 refdir = *refs->name
943 ? git_path_submodule(refs->name, "%s", refname.buf)
944 : git_path("%s", refname.buf);
945 if (stat(refdir, &st) < 0) {
946 ; /* silently ignore */
947 } else if (S_ISDIR(st.st_mode)) {
948 strbuf_addch(&refname, '/');
949 add_entry_to_dir(dir,
950 create_dir_entry(refs, refname.buf,
951 refname.len, 1));
952 } else {
953 if (*refs->name) {
954 hashclr(sha1);
955 flag = 0;
956 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {
957 hashclr(sha1);
958 flag |= REF_ISBROKEN;
960 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {
961 hashclr(sha1);
962 flag |= REF_ISBROKEN;
964 add_entry_to_dir(dir,
965 create_ref_entry(refname.buf, sha1, flag, 1));
967 strbuf_setlen(&refname, dirnamelen);
969 strbuf_release(&refname);
970 closedir(d);
973 static struct ref_dir *get_loose_refs(struct ref_cache *refs)
975 if (!refs->loose) {
977 * Mark the top-level directory complete because we
978 * are about to read the only subdirectory that can
979 * hold references:
981 refs->loose = create_dir_entry(refs, "", 0, 0);
983 * Create an incomplete entry for "refs/":
985 add_entry_to_dir(get_ref_dir(refs->loose),
986 create_dir_entry(refs, "refs/", 5, 1));
988 return get_ref_dir(refs->loose);
991 /* We allow "recursive" symbolic refs. Only within reason, though */
992 #define MAXDEPTH 5
993 #define MAXREFLEN (1024)
996 * Called by resolve_gitlink_ref_recursive() after it failed to read
997 * from the loose refs in ref_cache refs. Find <refname> in the
998 * packed-refs file for the submodule.
1000 static int resolve_gitlink_packed_ref(struct ref_cache *refs,
1001 const char *refname, unsigned char *sha1)
1003 struct ref_entry *ref;
1004 struct ref_dir *dir = get_packed_refs(refs);
1006 ref = find_ref(dir, refname);
1007 if (ref == NULL)
1008 return -1;
1010 memcpy(sha1, ref->u.value.sha1, 20);
1011 return 0;
1014 static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
1015 const char *refname, unsigned char *sha1,
1016 int recursion)
1018 int fd, len;
1019 char buffer[128], *p;
1020 char *path;
1022 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
1023 return -1;
1024 path = *refs->name
1025 ? git_path_submodule(refs->name, "%s", refname)
1026 : git_path("%s", refname);
1027 fd = open(path, O_RDONLY);
1028 if (fd < 0)
1029 return resolve_gitlink_packed_ref(refs, refname, sha1);
1031 len = read(fd, buffer, sizeof(buffer)-1);
1032 close(fd);
1033 if (len < 0)
1034 return -1;
1035 while (len && isspace(buffer[len-1]))
1036 len--;
1037 buffer[len] = 0;
1039 /* Was it a detached head or an old-fashioned symlink? */
1040 if (!get_sha1_hex(buffer, sha1))
1041 return 0;
1043 /* Symref? */
1044 if (strncmp(buffer, "ref:", 4))
1045 return -1;
1046 p = buffer + 4;
1047 while (isspace(*p))
1048 p++;
1050 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
1053 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
1055 int len = strlen(path), retval;
1056 char *submodule;
1057 struct ref_cache *refs;
1059 while (len && path[len-1] == '/')
1060 len--;
1061 if (!len)
1062 return -1;
1063 submodule = xstrndup(path, len);
1064 refs = get_ref_cache(submodule);
1065 free(submodule);
1067 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
1068 return retval;
1072 * Try to read ref from the packed references. On success, set sha1
1073 * and return 0; otherwise, return -1.
1075 static int get_packed_ref(const char *refname, unsigned char *sha1)
1077 struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
1078 struct ref_entry *entry = find_ref(packed, refname);
1079 if (entry) {
1080 hashcpy(sha1, entry->u.value.sha1);
1081 return 0;
1083 return -1;
1086 const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
1088 int depth = MAXDEPTH;
1089 ssize_t len;
1090 char buffer[256];
1091 static char refname_buffer[256];
1093 if (flag)
1094 *flag = 0;
1096 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
1097 return NULL;
1099 for (;;) {
1100 char path[PATH_MAX];
1101 struct stat st;
1102 char *buf;
1103 int fd;
1105 if (--depth < 0)
1106 return NULL;
1108 git_snpath(path, sizeof(path), "%s", refname);
1110 if (lstat(path, &st) < 0) {
1111 if (errno != ENOENT)
1112 return NULL;
1114 * The loose reference file does not exist;
1115 * check for a packed reference.
1117 if (!get_packed_ref(refname, sha1)) {
1118 if (flag)
1119 *flag |= REF_ISPACKED;
1120 return refname;
1122 /* The reference is not a packed reference, either. */
1123 if (reading) {
1124 return NULL;
1125 } else {
1126 hashclr(sha1);
1127 return refname;
1131 /* Follow "normalized" - ie "refs/.." symlinks by hand */
1132 if (S_ISLNK(st.st_mode)) {
1133 len = readlink(path, buffer, sizeof(buffer)-1);
1134 if (len < 0)
1135 return NULL;
1136 buffer[len] = 0;
1137 if (!prefixcmp(buffer, "refs/") &&
1138 !check_refname_format(buffer, 0)) {
1139 strcpy(refname_buffer, buffer);
1140 refname = refname_buffer;
1141 if (flag)
1142 *flag |= REF_ISSYMREF;
1143 continue;
1147 /* Is it a directory? */
1148 if (S_ISDIR(st.st_mode)) {
1149 errno = EISDIR;
1150 return NULL;
1154 * Anything else, just open it and try to use it as
1155 * a ref
1157 fd = open(path, O_RDONLY);
1158 if (fd < 0)
1159 return NULL;
1160 len = read_in_full(fd, buffer, sizeof(buffer)-1);
1161 close(fd);
1162 if (len < 0)
1163 return NULL;
1164 while (len && isspace(buffer[len-1]))
1165 len--;
1166 buffer[len] = '\0';
1169 * Is it a symbolic ref?
1171 if (prefixcmp(buffer, "ref:"))
1172 break;
1173 if (flag)
1174 *flag |= REF_ISSYMREF;
1175 buf = buffer + 4;
1176 while (isspace(*buf))
1177 buf++;
1178 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
1179 if (flag)
1180 *flag |= REF_ISBROKEN;
1181 return NULL;
1183 refname = strcpy(refname_buffer, buf);
1185 /* Please note that FETCH_HEAD has a second line containing other data. */
1186 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
1187 if (flag)
1188 *flag |= REF_ISBROKEN;
1189 return NULL;
1191 return refname;
1194 char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
1196 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
1197 return ret ? xstrdup(ret) : NULL;
1200 /* The argument to filter_refs */
1201 struct ref_filter {
1202 const char *pattern;
1203 each_ref_fn *fn;
1204 void *cb_data;
1207 int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)
1209 if (resolve_ref_unsafe(refname, sha1, reading, flags))
1210 return 0;
1211 return -1;
1214 int read_ref(const char *refname, unsigned char *sha1)
1216 return read_ref_full(refname, sha1, 1, NULL);
1219 int ref_exists(const char *refname)
1221 unsigned char sha1[20];
1222 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
1225 static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
1226 void *data)
1228 struct ref_filter *filter = (struct ref_filter *)data;
1229 if (fnmatch(filter->pattern, refname, 0))
1230 return 0;
1231 return filter->fn(refname, sha1, flags, filter->cb_data);
1234 int peel_ref(const char *refname, unsigned char *sha1)
1236 int flag;
1237 unsigned char base[20];
1238 struct object *o;
1240 if (current_ref && (current_ref->name == refname
1241 || !strcmp(current_ref->name, refname))) {
1242 if (current_ref->flag & REF_KNOWS_PEELED) {
1243 if (is_null_sha1(current_ref->u.value.peeled))
1244 return -1;
1245 hashcpy(sha1, current_ref->u.value.peeled);
1246 return 0;
1248 hashcpy(base, current_ref->u.value.sha1);
1249 goto fallback;
1252 if (read_ref_full(refname, base, 1, &flag))
1253 return -1;
1255 if ((flag & REF_ISPACKED)) {
1256 struct ref_dir *dir = get_packed_refs(get_ref_cache(NULL));
1257 struct ref_entry *r = find_ref(dir, refname);
1259 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
1260 hashcpy(sha1, r->u.value.peeled);
1261 return 0;
1265 fallback:
1266 o = lookup_unknown_object(base);
1267 if (o->type == OBJ_NONE) {
1268 int type = sha1_object_info(base, NULL);
1269 if (type < 0)
1270 return -1;
1271 o->type = type;
1274 if (o->type == OBJ_TAG) {
1275 o = deref_tag_noverify(o);
1276 if (o) {
1277 hashcpy(sha1, o->sha1);
1278 return 0;
1281 return -1;
1284 struct warn_if_dangling_data {
1285 FILE *fp;
1286 const char *refname;
1287 const char *msg_fmt;
1290 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
1291 int flags, void *cb_data)
1293 struct warn_if_dangling_data *d = cb_data;
1294 const char *resolves_to;
1295 unsigned char junk[20];
1297 if (!(flags & REF_ISSYMREF))
1298 return 0;
1300 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
1301 if (!resolves_to || strcmp(resolves_to, d->refname))
1302 return 0;
1304 fprintf(d->fp, d->msg_fmt, refname);
1305 fputc('\n', d->fp);
1306 return 0;
1309 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
1311 struct warn_if_dangling_data data;
1313 data.fp = fp;
1314 data.refname = refname;
1315 data.msg_fmt = msg_fmt;
1316 for_each_rawref(warn_if_dangling_symref, &data);
1319 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
1320 int trim, int flags, void *cb_data)
1322 struct ref_cache *refs = get_ref_cache(submodule);
1323 struct ref_dir *packed_dir = get_packed_refs(refs);
1324 struct ref_dir *loose_dir = get_loose_refs(refs);
1325 int retval = 0;
1327 if (base && *base) {
1328 packed_dir = find_containing_dir(packed_dir, base, 0);
1329 loose_dir = find_containing_dir(loose_dir, base, 0);
1332 if (packed_dir && loose_dir) {
1333 sort_ref_dir(packed_dir);
1334 sort_ref_dir(loose_dir);
1335 retval = do_for_each_ref_in_dirs(
1336 packed_dir, loose_dir,
1337 base, fn, trim, flags, cb_data);
1338 } else if (packed_dir) {
1339 sort_ref_dir(packed_dir);
1340 retval = do_for_each_ref_in_dir(
1341 packed_dir, 0,
1342 base, fn, trim, flags, cb_data);
1343 } else if (loose_dir) {
1344 sort_ref_dir(loose_dir);
1345 retval = do_for_each_ref_in_dir(
1346 loose_dir, 0,
1347 base, fn, trim, flags, cb_data);
1350 return retval;
1353 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
1355 unsigned char sha1[20];
1356 int flag;
1358 if (submodule) {
1359 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
1360 return fn("HEAD", sha1, 0, cb_data);
1362 return 0;
1365 if (!read_ref_full("HEAD", sha1, 1, &flag))
1366 return fn("HEAD", sha1, flag, cb_data);
1368 return 0;
1371 int head_ref(each_ref_fn fn, void *cb_data)
1373 return do_head_ref(NULL, fn, cb_data);
1376 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1378 return do_head_ref(submodule, fn, cb_data);
1381 int for_each_ref(each_ref_fn fn, void *cb_data)
1383 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
1386 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1388 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
1391 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1393 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
1396 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1397 each_ref_fn fn, void *cb_data)
1399 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
1402 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
1404 return for_each_ref_in("refs/tags/", fn, cb_data);
1407 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1409 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
1412 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
1414 return for_each_ref_in("refs/heads/", fn, cb_data);
1417 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1419 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
1422 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
1424 return for_each_ref_in("refs/remotes/", fn, cb_data);
1427 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1429 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
1432 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1434 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
1437 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
1439 struct strbuf buf = STRBUF_INIT;
1440 int ret = 0;
1441 unsigned char sha1[20];
1442 int flag;
1444 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
1445 if (!read_ref_full(buf.buf, sha1, 1, &flag))
1446 ret = fn(buf.buf, sha1, flag, cb_data);
1447 strbuf_release(&buf);
1449 return ret;
1452 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1454 struct strbuf buf = STRBUF_INIT;
1455 int ret;
1456 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1457 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
1458 strbuf_release(&buf);
1459 return ret;
1462 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
1463 const char *prefix, void *cb_data)
1465 struct strbuf real_pattern = STRBUF_INIT;
1466 struct ref_filter filter;
1467 int ret;
1469 if (!prefix && prefixcmp(pattern, "refs/"))
1470 strbuf_addstr(&real_pattern, "refs/");
1471 else if (prefix)
1472 strbuf_addstr(&real_pattern, prefix);
1473 strbuf_addstr(&real_pattern, pattern);
1475 if (!has_glob_specials(pattern)) {
1476 /* Append implied '/' '*' if not present. */
1477 if (real_pattern.buf[real_pattern.len - 1] != '/')
1478 strbuf_addch(&real_pattern, '/');
1479 /* No need to check for '*', there is none. */
1480 strbuf_addch(&real_pattern, '*');
1483 filter.pattern = real_pattern.buf;
1484 filter.fn = fn;
1485 filter.cb_data = cb_data;
1486 ret = for_each_ref(filter_refs, &filter);
1488 strbuf_release(&real_pattern);
1489 return ret;
1492 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
1494 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
1497 int for_each_rawref(each_ref_fn fn, void *cb_data)
1499 return do_for_each_ref(NULL, "", fn, 0,
1500 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1503 const char *prettify_refname(const char *name)
1505 return name + (
1506 !prefixcmp(name, "refs/heads/") ? 11 :
1507 !prefixcmp(name, "refs/tags/") ? 10 :
1508 !prefixcmp(name, "refs/remotes/") ? 13 :
1512 const char *ref_rev_parse_rules[] = {
1513 "%.*s",
1514 "refs/%.*s",
1515 "refs/tags/%.*s",
1516 "refs/heads/%.*s",
1517 "refs/remotes/%.*s",
1518 "refs/remotes/%.*s/HEAD",
1519 NULL
1522 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1524 const char **p;
1525 const int abbrev_name_len = strlen(abbrev_name);
1527 for (p = rules; *p; p++) {
1528 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1529 return 1;
1533 return 0;
1536 static struct ref_lock *verify_lock(struct ref_lock *lock,
1537 const unsigned char *old_sha1, int mustexist)
1539 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
1540 error("Can't verify ref %s", lock->ref_name);
1541 unlock_ref(lock);
1542 return NULL;
1544 if (hashcmp(lock->old_sha1, old_sha1)) {
1545 error("Ref %s is at %s but expected %s", lock->ref_name,
1546 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1547 unlock_ref(lock);
1548 return NULL;
1550 return lock;
1553 static int remove_empty_directories(const char *file)
1555 /* we want to create a file but there is a directory there;
1556 * if that is an empty directory (or a directory that contains
1557 * only empty directories), remove them.
1559 struct strbuf path;
1560 int result;
1562 strbuf_init(&path, 20);
1563 strbuf_addstr(&path, file);
1565 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1567 strbuf_release(&path);
1569 return result;
1573 * *string and *len will only be substituted, and *string returned (for
1574 * later free()ing) if the string passed in is a magic short-hand form
1575 * to name a branch.
1577 static char *substitute_branch_name(const char **string, int *len)
1579 struct strbuf buf = STRBUF_INIT;
1580 int ret = interpret_branch_name(*string, &buf);
1582 if (ret == *len) {
1583 size_t size;
1584 *string = strbuf_detach(&buf, &size);
1585 *len = size;
1586 return (char *)*string;
1589 return NULL;
1592 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1594 char *last_branch = substitute_branch_name(&str, &len);
1595 const char **p, *r;
1596 int refs_found = 0;
1598 *ref = NULL;
1599 for (p = ref_rev_parse_rules; *p; p++) {
1600 char fullref[PATH_MAX];
1601 unsigned char sha1_from_ref[20];
1602 unsigned char *this_result;
1603 int flag;
1605 this_result = refs_found ? sha1_from_ref : sha1;
1606 mksnpath(fullref, sizeof(fullref), *p, len, str);
1607 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
1608 if (r) {
1609 if (!refs_found++)
1610 *ref = xstrdup(r);
1611 if (!warn_ambiguous_refs)
1612 break;
1613 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
1614 warning("ignoring dangling symref %s.", fullref);
1615 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1616 warning("ignoring broken ref %s.", fullref);
1619 free(last_branch);
1620 return refs_found;
1623 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1625 char *last_branch = substitute_branch_name(&str, &len);
1626 const char **p;
1627 int logs_found = 0;
1629 *log = NULL;
1630 for (p = ref_rev_parse_rules; *p; p++) {
1631 struct stat st;
1632 unsigned char hash[20];
1633 char path[PATH_MAX];
1634 const char *ref, *it;
1636 mksnpath(path, sizeof(path), *p, len, str);
1637 ref = resolve_ref_unsafe(path, hash, 1, NULL);
1638 if (!ref)
1639 continue;
1640 if (!stat(git_path("logs/%s", path), &st) &&
1641 S_ISREG(st.st_mode))
1642 it = path;
1643 else if (strcmp(ref, path) &&
1644 !stat(git_path("logs/%s", ref), &st) &&
1645 S_ISREG(st.st_mode))
1646 it = ref;
1647 else
1648 continue;
1649 if (!logs_found++) {
1650 *log = xstrdup(it);
1651 hashcpy(sha1, hash);
1653 if (!warn_ambiguous_refs)
1654 break;
1656 free(last_branch);
1657 return logs_found;
1660 static struct ref_lock *lock_ref_sha1_basic(const char *refname,
1661 const unsigned char *old_sha1,
1662 int flags, int *type_p)
1664 char *ref_file;
1665 const char *orig_refname = refname;
1666 struct ref_lock *lock;
1667 int last_errno = 0;
1668 int type, lflags;
1669 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1670 int missing = 0;
1672 lock = xcalloc(1, sizeof(struct ref_lock));
1673 lock->lock_fd = -1;
1675 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
1676 if (!refname && errno == EISDIR) {
1677 /* we are trying to lock foo but we used to
1678 * have foo/bar which now does not exist;
1679 * it is normal for the empty directory 'foo'
1680 * to remain.
1682 ref_file = git_path("%s", orig_refname);
1683 if (remove_empty_directories(ref_file)) {
1684 last_errno = errno;
1685 error("there are still refs under '%s'", orig_refname);
1686 goto error_return;
1688 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
1690 if (type_p)
1691 *type_p = type;
1692 if (!refname) {
1693 last_errno = errno;
1694 error("unable to resolve reference %s: %s",
1695 orig_refname, strerror(errno));
1696 goto error_return;
1698 missing = is_null_sha1(lock->old_sha1);
1699 /* When the ref did not exist and we are creating it,
1700 * make sure there is no existing ref that is packed
1701 * whose name begins with our refname, nor a ref whose
1702 * name is a proper prefix of our refname.
1704 if (missing &&
1705 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
1706 last_errno = ENOTDIR;
1707 goto error_return;
1710 lock->lk = xcalloc(1, sizeof(struct lock_file));
1712 lflags = LOCK_DIE_ON_ERROR;
1713 if (flags & REF_NODEREF) {
1714 refname = orig_refname;
1715 lflags |= LOCK_NODEREF;
1717 lock->ref_name = xstrdup(refname);
1718 lock->orig_ref_name = xstrdup(orig_refname);
1719 ref_file = git_path("%s", refname);
1720 if (missing)
1721 lock->force_write = 1;
1722 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1723 lock->force_write = 1;
1725 if (safe_create_leading_directories(ref_file)) {
1726 last_errno = errno;
1727 error("unable to create directory for %s", ref_file);
1728 goto error_return;
1731 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1732 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1734 error_return:
1735 unlock_ref(lock);
1736 errno = last_errno;
1737 return NULL;
1740 struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
1742 char refpath[PATH_MAX];
1743 if (check_refname_format(refname, 0))
1744 return NULL;
1745 strcpy(refpath, mkpath("refs/%s", refname));
1746 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1749 struct ref_lock *lock_any_ref_for_update(const char *refname,
1750 const unsigned char *old_sha1, int flags)
1752 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
1753 return NULL;
1754 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
1757 struct repack_without_ref_sb {
1758 const char *refname;
1759 int fd;
1762 static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,
1763 int flags, void *cb_data)
1765 struct repack_without_ref_sb *data = cb_data;
1766 char line[PATH_MAX + 100];
1767 int len;
1769 if (!strcmp(data->refname, refname))
1770 return 0;
1771 len = snprintf(line, sizeof(line), "%s %s\n",
1772 sha1_to_hex(sha1), refname);
1773 /* this should not happen but just being defensive */
1774 if (len > sizeof(line))
1775 die("too long a refname '%s'", refname);
1776 write_or_die(data->fd, line, len);
1777 return 0;
1780 static struct lock_file packlock;
1782 static int repack_without_ref(const char *refname)
1784 struct repack_without_ref_sb data;
1785 struct ref_cache *refs = get_ref_cache(NULL);
1786 struct ref_dir *packed = get_packed_refs(refs);
1787 if (find_ref(packed, refname) == NULL)
1788 return 0;
1789 data.refname = refname;
1790 data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1791 if (data.fd < 0) {
1792 unable_to_lock_error(git_path("packed-refs"), errno);
1793 return error("cannot delete '%s' from packed refs", refname);
1795 clear_packed_ref_cache(refs);
1796 packed = get_packed_refs(refs);
1797 do_for_each_ref_in_dir(packed, 0, "", repack_without_ref_fn, 0, 0, &data);
1798 return commit_lock_file(&packlock);
1801 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1803 struct ref_lock *lock;
1804 int err, i = 0, ret = 0, flag = 0;
1806 lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);
1807 if (!lock)
1808 return 1;
1809 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1810 /* loose */
1811 i = strlen(lock->lk->filename) - 5; /* .lock */
1812 lock->lk->filename[i] = 0;
1813 err = unlink_or_warn(lock->lk->filename);
1814 if (err && errno != ENOENT)
1815 ret = 1;
1817 lock->lk->filename[i] = '.';
1819 /* removing the loose one could have resurrected an earlier
1820 * packed one. Also, if it was not loose we need to repack
1821 * without it.
1823 ret |= repack_without_ref(lock->ref_name);
1825 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1826 invalidate_ref_cache(NULL);
1827 unlock_ref(lock);
1828 return ret;
1832 * People using contrib's git-new-workdir have .git/logs/refs ->
1833 * /some/other/path/.git/logs/refs, and that may live on another device.
1835 * IOW, to avoid cross device rename errors, the temporary renamed log must
1836 * live into logs/refs.
1838 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1840 int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
1842 unsigned char sha1[20], orig_sha1[20];
1843 int flag = 0, logmoved = 0;
1844 struct ref_lock *lock;
1845 struct stat loginfo;
1846 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
1847 const char *symref = NULL;
1848 struct ref_cache *refs = get_ref_cache(NULL);
1850 if (log && S_ISLNK(loginfo.st_mode))
1851 return error("reflog for %s is a symlink", oldrefname);
1853 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
1854 if (flag & REF_ISSYMREF)
1855 return error("refname %s is a symbolic ref, renaming it is not supported",
1856 oldrefname);
1857 if (!symref)
1858 return error("refname %s not found", oldrefname);
1860 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
1861 return 1;
1863 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
1864 return 1;
1866 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
1867 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1868 oldrefname, strerror(errno));
1870 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
1871 error("unable to delete old %s", oldrefname);
1872 goto rollback;
1875 if (!read_ref_full(newrefname, sha1, 1, &flag) &&
1876 delete_ref(newrefname, sha1, REF_NODEREF)) {
1877 if (errno==EISDIR) {
1878 if (remove_empty_directories(git_path("%s", newrefname))) {
1879 error("Directory not empty: %s", newrefname);
1880 goto rollback;
1882 } else {
1883 error("unable to delete existing %s", newrefname);
1884 goto rollback;
1888 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
1889 error("unable to create directory for %s", newrefname);
1890 goto rollback;
1893 retry:
1894 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
1895 if (errno==EISDIR || errno==ENOTDIR) {
1897 * rename(a, b) when b is an existing
1898 * directory ought to result in ISDIR, but
1899 * Solaris 5.8 gives ENOTDIR. Sheesh.
1901 if (remove_empty_directories(git_path("logs/%s", newrefname))) {
1902 error("Directory not empty: logs/%s", newrefname);
1903 goto rollback;
1905 goto retry;
1906 } else {
1907 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1908 newrefname, strerror(errno));
1909 goto rollback;
1912 logmoved = log;
1914 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
1915 if (!lock) {
1916 error("unable to lock %s for update", newrefname);
1917 goto rollback;
1919 lock->force_write = 1;
1920 hashcpy(lock->old_sha1, orig_sha1);
1921 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1922 error("unable to write current sha1 into %s", newrefname);
1923 goto rollback;
1926 return 0;
1928 rollback:
1929 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
1930 if (!lock) {
1931 error("unable to lock %s for rollback", oldrefname);
1932 goto rollbacklog;
1935 lock->force_write = 1;
1936 flag = log_all_ref_updates;
1937 log_all_ref_updates = 0;
1938 if (write_ref_sha1(lock, orig_sha1, NULL))
1939 error("unable to write current sha1 into %s", oldrefname);
1940 log_all_ref_updates = flag;
1942 rollbacklog:
1943 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
1944 error("unable to restore logfile %s from %s: %s",
1945 oldrefname, newrefname, strerror(errno));
1946 if (!logmoved && log &&
1947 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
1948 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1949 oldrefname, strerror(errno));
1951 return 1;
1954 int close_ref(struct ref_lock *lock)
1956 if (close_lock_file(lock->lk))
1957 return -1;
1958 lock->lock_fd = -1;
1959 return 0;
1962 int commit_ref(struct ref_lock *lock)
1964 if (commit_lock_file(lock->lk))
1965 return -1;
1966 lock->lock_fd = -1;
1967 return 0;
1970 void unlock_ref(struct ref_lock *lock)
1972 /* Do not free lock->lk -- atexit() still looks at them */
1973 if (lock->lk)
1974 rollback_lock_file(lock->lk);
1975 free(lock->ref_name);
1976 free(lock->orig_ref_name);
1977 free(lock);
1981 * copy the reflog message msg to buf, which has been allocated sufficiently
1982 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1983 * because reflog file is one line per entry.
1985 static int copy_msg(char *buf, const char *msg)
1987 char *cp = buf;
1988 char c;
1989 int wasspace = 1;
1991 *cp++ = '\t';
1992 while ((c = *msg++)) {
1993 if (wasspace && isspace(c))
1994 continue;
1995 wasspace = isspace(c);
1996 if (wasspace)
1997 c = ' ';
1998 *cp++ = c;
2000 while (buf < cp && isspace(cp[-1]))
2001 cp--;
2002 *cp++ = '\n';
2003 return cp - buf;
2006 int log_ref_setup(const char *refname, char *logfile, int bufsize)
2008 int logfd, oflags = O_APPEND | O_WRONLY;
2010 git_snpath(logfile, bufsize, "logs/%s", refname);
2011 if (log_all_ref_updates &&
2012 (!prefixcmp(refname, "refs/heads/") ||
2013 !prefixcmp(refname, "refs/remotes/") ||
2014 !prefixcmp(refname, "refs/notes/") ||
2015 !strcmp(refname, "HEAD"))) {
2016 if (safe_create_leading_directories(logfile) < 0)
2017 return error("unable to create directory for %s",
2018 logfile);
2019 oflags |= O_CREAT;
2022 logfd = open(logfile, oflags, 0666);
2023 if (logfd < 0) {
2024 if (!(oflags & O_CREAT) && errno == ENOENT)
2025 return 0;
2027 if ((oflags & O_CREAT) && errno == EISDIR) {
2028 if (remove_empty_directories(logfile)) {
2029 return error("There are still logs under '%s'",
2030 logfile);
2032 logfd = open(logfile, oflags, 0666);
2035 if (logfd < 0)
2036 return error("Unable to append to %s: %s",
2037 logfile, strerror(errno));
2040 adjust_shared_perm(logfile);
2041 close(logfd);
2042 return 0;
2045 static int log_ref_write(const char *refname, const unsigned char *old_sha1,
2046 const unsigned char *new_sha1, const char *msg)
2048 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
2049 unsigned maxlen, len;
2050 int msglen;
2051 char log_file[PATH_MAX];
2052 char *logrec;
2053 const char *committer;
2055 if (log_all_ref_updates < 0)
2056 log_all_ref_updates = !is_bare_repository();
2058 result = log_ref_setup(refname, log_file, sizeof(log_file));
2059 if (result)
2060 return result;
2062 logfd = open(log_file, oflags);
2063 if (logfd < 0)
2064 return 0;
2065 msglen = msg ? strlen(msg) : 0;
2066 committer = git_committer_info(0);
2067 maxlen = strlen(committer) + msglen + 100;
2068 logrec = xmalloc(maxlen);
2069 len = sprintf(logrec, "%s %s %s\n",
2070 sha1_to_hex(old_sha1),
2071 sha1_to_hex(new_sha1),
2072 committer);
2073 if (msglen)
2074 len += copy_msg(logrec + len - 1, msg) - 1;
2075 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
2076 free(logrec);
2077 if (close(logfd) != 0 || written != len)
2078 return error("Unable to append to %s", log_file);
2079 return 0;
2082 static int is_branch(const char *refname)
2084 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
2087 int write_ref_sha1(struct ref_lock *lock,
2088 const unsigned char *sha1, const char *logmsg)
2090 static char term = '\n';
2091 struct object *o;
2093 if (!lock)
2094 return -1;
2095 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
2096 unlock_ref(lock);
2097 return 0;
2099 o = parse_object(sha1);
2100 if (!o) {
2101 error("Trying to write ref %s with nonexistent object %s",
2102 lock->ref_name, sha1_to_hex(sha1));
2103 unlock_ref(lock);
2104 return -1;
2106 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
2107 error("Trying to write non-commit object %s to branch %s",
2108 sha1_to_hex(sha1), lock->ref_name);
2109 unlock_ref(lock);
2110 return -1;
2112 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
2113 write_in_full(lock->lock_fd, &term, 1) != 1
2114 || close_ref(lock) < 0) {
2115 error("Couldn't write %s", lock->lk->filename);
2116 unlock_ref(lock);
2117 return -1;
2119 clear_loose_ref_cache(get_ref_cache(NULL));
2120 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
2121 (strcmp(lock->ref_name, lock->orig_ref_name) &&
2122 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
2123 unlock_ref(lock);
2124 return -1;
2126 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
2128 * Special hack: If a branch is updated directly and HEAD
2129 * points to it (may happen on the remote side of a push
2130 * for example) then logically the HEAD reflog should be
2131 * updated too.
2132 * A generic solution implies reverse symref information,
2133 * but finding all symrefs pointing to the given branch
2134 * would be rather costly for this rare event (the direct
2135 * update of a branch) to be worth it. So let's cheat and
2136 * check with HEAD only which should cover 99% of all usage
2137 * scenarios (even 100% of the default ones).
2139 unsigned char head_sha1[20];
2140 int head_flag;
2141 const char *head_ref;
2142 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
2143 if (head_ref && (head_flag & REF_ISSYMREF) &&
2144 !strcmp(head_ref, lock->ref_name))
2145 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
2147 if (commit_ref(lock)) {
2148 error("Couldn't set %s", lock->ref_name);
2149 unlock_ref(lock);
2150 return -1;
2152 unlock_ref(lock);
2153 return 0;
2156 int create_symref(const char *ref_target, const char *refs_heads_master,
2157 const char *logmsg)
2159 const char *lockpath;
2160 char ref[1000];
2161 int fd, len, written;
2162 char *git_HEAD = git_pathdup("%s", ref_target);
2163 unsigned char old_sha1[20], new_sha1[20];
2165 if (logmsg && read_ref(ref_target, old_sha1))
2166 hashclr(old_sha1);
2168 if (safe_create_leading_directories(git_HEAD) < 0)
2169 return error("unable to create directory for %s", git_HEAD);
2171 #ifndef NO_SYMLINK_HEAD
2172 if (prefer_symlink_refs) {
2173 unlink(git_HEAD);
2174 if (!symlink(refs_heads_master, git_HEAD))
2175 goto done;
2176 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
2178 #endif
2180 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
2181 if (sizeof(ref) <= len) {
2182 error("refname too long: %s", refs_heads_master);
2183 goto error_free_return;
2185 lockpath = mkpath("%s.lock", git_HEAD);
2186 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
2187 if (fd < 0) {
2188 error("Unable to open %s for writing", lockpath);
2189 goto error_free_return;
2191 written = write_in_full(fd, ref, len);
2192 if (close(fd) != 0 || written != len) {
2193 error("Unable to write to %s", lockpath);
2194 goto error_unlink_return;
2196 if (rename(lockpath, git_HEAD) < 0) {
2197 error("Unable to create %s", git_HEAD);
2198 goto error_unlink_return;
2200 if (adjust_shared_perm(git_HEAD)) {
2201 error("Unable to fix permissions on %s", lockpath);
2202 error_unlink_return:
2203 unlink_or_warn(lockpath);
2204 error_free_return:
2205 free(git_HEAD);
2206 return -1;
2209 #ifndef NO_SYMLINK_HEAD
2210 done:
2211 #endif
2212 if (logmsg && !read_ref(refs_heads_master, new_sha1))
2213 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
2215 free(git_HEAD);
2216 return 0;
2219 static char *ref_msg(const char *line, const char *endp)
2221 const char *ep;
2222 line += 82;
2223 ep = memchr(line, '\n', endp - line);
2224 if (!ep)
2225 ep = endp;
2226 return xmemdupz(line, ep - line);
2229 int read_ref_at(const char *refname, unsigned long at_time, int cnt,
2230 unsigned char *sha1, char **msg,
2231 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
2233 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
2234 char *tz_c;
2235 int logfd, tz, reccnt = 0;
2236 struct stat st;
2237 unsigned long date;
2238 unsigned char logged_sha1[20];
2239 void *log_mapped;
2240 size_t mapsz;
2242 logfile = git_path("logs/%s", refname);
2243 logfd = open(logfile, O_RDONLY, 0);
2244 if (logfd < 0)
2245 die_errno("Unable to read log '%s'", logfile);
2246 fstat(logfd, &st);
2247 if (!st.st_size)
2248 die("Log %s is empty.", logfile);
2249 mapsz = xsize_t(st.st_size);
2250 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
2251 logdata = log_mapped;
2252 close(logfd);
2254 lastrec = NULL;
2255 rec = logend = logdata + st.st_size;
2256 while (logdata < rec) {
2257 reccnt++;
2258 if (logdata < rec && *(rec-1) == '\n')
2259 rec--;
2260 lastgt = NULL;
2261 while (logdata < rec && *(rec-1) != '\n') {
2262 rec--;
2263 if (*rec == '>')
2264 lastgt = rec;
2266 if (!lastgt)
2267 die("Log %s is corrupt.", logfile);
2268 date = strtoul(lastgt + 1, &tz_c, 10);
2269 if (date <= at_time || cnt == 0) {
2270 tz = strtoul(tz_c, NULL, 10);
2271 if (msg)
2272 *msg = ref_msg(rec, logend);
2273 if (cutoff_time)
2274 *cutoff_time = date;
2275 if (cutoff_tz)
2276 *cutoff_tz = tz;
2277 if (cutoff_cnt)
2278 *cutoff_cnt = reccnt - 1;
2279 if (lastrec) {
2280 if (get_sha1_hex(lastrec, logged_sha1))
2281 die("Log %s is corrupt.", logfile);
2282 if (get_sha1_hex(rec + 41, sha1))
2283 die("Log %s is corrupt.", logfile);
2284 if (hashcmp(logged_sha1, sha1)) {
2285 warning("Log %s has gap after %s.",
2286 logfile, show_date(date, tz, DATE_RFC2822));
2289 else if (date == at_time) {
2290 if (get_sha1_hex(rec + 41, sha1))
2291 die("Log %s is corrupt.", logfile);
2293 else {
2294 if (get_sha1_hex(rec + 41, logged_sha1))
2295 die("Log %s is corrupt.", logfile);
2296 if (hashcmp(logged_sha1, sha1)) {
2297 warning("Log %s unexpectedly ended on %s.",
2298 logfile, show_date(date, tz, DATE_RFC2822));
2301 munmap(log_mapped, mapsz);
2302 return 0;
2304 lastrec = rec;
2305 if (cnt > 0)
2306 cnt--;
2309 rec = logdata;
2310 while (rec < logend && *rec != '>' && *rec != '\n')
2311 rec++;
2312 if (rec == logend || *rec == '\n')
2313 die("Log %s is corrupt.", logfile);
2314 date = strtoul(rec + 1, &tz_c, 10);
2315 tz = strtoul(tz_c, NULL, 10);
2316 if (get_sha1_hex(logdata, sha1))
2317 die("Log %s is corrupt.", logfile);
2318 if (is_null_sha1(sha1)) {
2319 if (get_sha1_hex(logdata + 41, sha1))
2320 die("Log %s is corrupt.", logfile);
2322 if (msg)
2323 *msg = ref_msg(logdata, logend);
2324 munmap(log_mapped, mapsz);
2326 if (cutoff_time)
2327 *cutoff_time = date;
2328 if (cutoff_tz)
2329 *cutoff_tz = tz;
2330 if (cutoff_cnt)
2331 *cutoff_cnt = reccnt;
2332 return 1;
2335 static int show_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn, void *cb_data)
2337 unsigned char osha1[20], nsha1[20];
2338 char *email_end, *message;
2339 unsigned long timestamp;
2340 int tz;
2342 /* old SP new SP name <email> SP time TAB msg LF */
2343 if (sb->len < 83 || sb->buf[sb->len - 1] != '\n' ||
2344 get_sha1_hex(sb->buf, osha1) || sb->buf[40] != ' ' ||
2345 get_sha1_hex(sb->buf + 41, nsha1) || sb->buf[81] != ' ' ||
2346 !(email_end = strchr(sb->buf + 82, '>')) ||
2347 email_end[1] != ' ' ||
2348 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
2349 !message || message[0] != ' ' ||
2350 (message[1] != '+' && message[1] != '-') ||
2351 !isdigit(message[2]) || !isdigit(message[3]) ||
2352 !isdigit(message[4]) || !isdigit(message[5]))
2353 return 0; /* corrupt? */
2354 email_end[1] = '\0';
2355 tz = strtol(message + 1, NULL, 10);
2356 if (message[6] != '\t')
2357 message += 6;
2358 else
2359 message += 7;
2360 return fn(osha1, nsha1, sb->buf + 82, timestamp, tz, message, cb_data);
2363 static char *find_beginning_of_line(char *bob, char *scan)
2365 while (bob < scan && *(--scan) != '\n')
2366 ; /* keep scanning backwards */
2368 * Return either beginning of the buffer, or LF at the end of
2369 * the previous line.
2371 return scan;
2374 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data)
2376 struct strbuf sb = STRBUF_INIT;
2377 FILE *logfp;
2378 long pos;
2379 int ret = 0, at_tail = 1;
2381 logfp = fopen(git_path("logs/%s", refname), "r");
2382 if (!logfp)
2383 return -1;
2385 /* Jump to the end */
2386 if (fseek(logfp, 0, SEEK_END) < 0)
2387 return error("cannot seek back reflog for %s: %s",
2388 refname, strerror(errno));
2389 pos = ftell(logfp);
2390 while (!ret && 0 < pos) {
2391 int cnt;
2392 size_t nread;
2393 char buf[BUFSIZ];
2394 char *endp, *scanp;
2396 /* Fill next block from the end */
2397 cnt = (sizeof(buf) < pos) ? sizeof(buf) : pos;
2398 if (fseek(logfp, pos - cnt, SEEK_SET))
2399 return error("cannot seek back reflog for %s: %s",
2400 refname, strerror(errno));
2401 nread = fread(buf, cnt, 1, logfp);
2402 if (nread != 1)
2403 return error("cannot read %d bytes from reflog for %s: %s",
2404 cnt, refname, strerror(errno));
2405 pos -= cnt;
2407 scanp = endp = buf + cnt;
2408 if (at_tail && scanp[-1] == '\n')
2409 /* Looking at the final LF at the end of the file */
2410 scanp--;
2411 at_tail = 0;
2413 while (buf < scanp) {
2415 * terminating LF of the previous line, or the beginning
2416 * of the buffer.
2418 char *bp;
2420 bp = find_beginning_of_line(buf, scanp);
2422 if (*bp != '\n') {
2423 strbuf_splice(&sb, 0, 0, buf, endp - buf);
2424 if (pos)
2425 break; /* need to fill another block */
2426 scanp = buf - 1; /* leave loop */
2427 } else {
2429 * (bp + 1) thru endp is the beginning of the
2430 * current line we have in sb
2432 strbuf_splice(&sb, 0, 0, bp + 1, endp - (bp + 1));
2433 scanp = bp;
2434 endp = bp + 1;
2436 ret = show_one_reflog_ent(&sb, fn, cb_data);
2437 strbuf_reset(&sb);
2438 if (ret)
2439 break;
2443 if (!ret && sb.len)
2444 ret = show_one_reflog_ent(&sb, fn, cb_data);
2446 fclose(logfp);
2447 strbuf_release(&sb);
2448 return ret;
2451 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
2453 FILE *logfp;
2454 struct strbuf sb = STRBUF_INIT;
2455 int ret = 0;
2457 logfp = fopen(git_path("logs/%s", refname), "r");
2458 if (!logfp)
2459 return -1;
2461 while (!ret && !strbuf_getwholeline(&sb, logfp, '\n'))
2462 ret = show_one_reflog_ent(&sb, fn, cb_data);
2463 fclose(logfp);
2464 strbuf_release(&sb);
2465 return ret;
2468 * Call fn for each reflog in the namespace indicated by name. name
2469 * must be empty or end with '/'. Name will be used as a scratch
2470 * space, but its contents will be restored before return.
2472 static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)
2474 DIR *d = opendir(git_path("logs/%s", name->buf));
2475 int retval = 0;
2476 struct dirent *de;
2477 int oldlen = name->len;
2479 if (!d)
2480 return name->len ? errno : 0;
2482 while ((de = readdir(d)) != NULL) {
2483 struct stat st;
2485 if (de->d_name[0] == '.')
2486 continue;
2487 if (has_extension(de->d_name, ".lock"))
2488 continue;
2489 strbuf_addstr(name, de->d_name);
2490 if (stat(git_path("logs/%s", name->buf), &st) < 0) {
2491 ; /* silently ignore */
2492 } else {
2493 if (S_ISDIR(st.st_mode)) {
2494 strbuf_addch(name, '/');
2495 retval = do_for_each_reflog(name, fn, cb_data);
2496 } else {
2497 unsigned char sha1[20];
2498 if (read_ref_full(name->buf, sha1, 0, NULL))
2499 retval = error("bad ref for %s", name->buf);
2500 else
2501 retval = fn(name->buf, sha1, 0, cb_data);
2503 if (retval)
2504 break;
2506 strbuf_setlen(name, oldlen);
2508 closedir(d);
2509 return retval;
2512 int for_each_reflog(each_ref_fn fn, void *cb_data)
2514 int retval;
2515 struct strbuf name;
2516 strbuf_init(&name, PATH_MAX);
2517 retval = do_for_each_reflog(&name, fn, cb_data);
2518 strbuf_release(&name);
2519 return retval;
2522 int update_ref(const char *action, const char *refname,
2523 const unsigned char *sha1, const unsigned char *oldval,
2524 int flags, enum action_on_err onerr)
2526 static struct ref_lock *lock;
2527 lock = lock_any_ref_for_update(refname, oldval, flags);
2528 if (!lock) {
2529 const char *str = "Cannot lock the ref '%s'.";
2530 switch (onerr) {
2531 case MSG_ON_ERR: error(str, refname); break;
2532 case DIE_ON_ERR: die(str, refname); break;
2533 case QUIET_ON_ERR: break;
2535 return 1;
2537 if (write_ref_sha1(lock, sha1, action) < 0) {
2538 const char *str = "Cannot update the ref '%s'.";
2539 switch (onerr) {
2540 case MSG_ON_ERR: error(str, refname); break;
2541 case DIE_ON_ERR: die(str, refname); break;
2542 case QUIET_ON_ERR: break;
2544 return 1;
2546 return 0;
2549 struct ref *find_ref_by_name(const struct ref *list, const char *name)
2551 for ( ; list; list = list->next)
2552 if (!strcmp(list->name, name))
2553 return (struct ref *)list;
2554 return NULL;
2558 * generate a format suitable for scanf from a ref_rev_parse_rules
2559 * rule, that is replace the "%.*s" spec with a "%s" spec
2561 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
2563 char *spec;
2565 spec = strstr(rule, "%.*s");
2566 if (!spec || strstr(spec + 4, "%.*s"))
2567 die("invalid rule in ref_rev_parse_rules: %s", rule);
2569 /* copy all until spec */
2570 strncpy(scanf_fmt, rule, spec - rule);
2571 scanf_fmt[spec - rule] = '\0';
2572 /* copy new spec */
2573 strcat(scanf_fmt, "%s");
2574 /* copy remaining rule */
2575 strcat(scanf_fmt, spec + 4);
2577 return;
2580 char *shorten_unambiguous_ref(const char *refname, int strict)
2582 int i;
2583 static char **scanf_fmts;
2584 static int nr_rules;
2585 char *short_name;
2587 /* pre generate scanf formats from ref_rev_parse_rules[] */
2588 if (!nr_rules) {
2589 size_t total_len = 0;
2591 /* the rule list is NULL terminated, count them first */
2592 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2593 /* no +1 because strlen("%s") < strlen("%.*s") */
2594 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2596 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2598 total_len = 0;
2599 for (i = 0; i < nr_rules; i++) {
2600 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2601 + total_len;
2602 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2603 total_len += strlen(ref_rev_parse_rules[i]);
2607 /* bail out if there are no rules */
2608 if (!nr_rules)
2609 return xstrdup(refname);
2611 /* buffer for scanf result, at most refname must fit */
2612 short_name = xstrdup(refname);
2614 /* skip first rule, it will always match */
2615 for (i = nr_rules - 1; i > 0 ; --i) {
2616 int j;
2617 int rules_to_fail = i;
2618 int short_name_len;
2620 if (1 != sscanf(refname, scanf_fmts[i], short_name))
2621 continue;
2623 short_name_len = strlen(short_name);
2626 * in strict mode, all (except the matched one) rules
2627 * must fail to resolve to a valid non-ambiguous ref
2629 if (strict)
2630 rules_to_fail = nr_rules;
2633 * check if the short name resolves to a valid ref,
2634 * but use only rules prior to the matched one
2636 for (j = 0; j < rules_to_fail; j++) {
2637 const char *rule = ref_rev_parse_rules[j];
2638 char refname[PATH_MAX];
2640 /* skip matched rule */
2641 if (i == j)
2642 continue;
2645 * the short name is ambiguous, if it resolves
2646 * (with this previous rule) to a valid ref
2647 * read_ref() returns 0 on success
2649 mksnpath(refname, sizeof(refname),
2650 rule, short_name_len, short_name);
2651 if (ref_exists(refname))
2652 break;
2656 * short name is non-ambiguous if all previous rules
2657 * haven't resolved to a valid ref
2659 if (j == rules_to_fail)
2660 return short_name;
2663 free(short_name);
2664 return xstrdup(refname);
2667 static struct string_list *hide_refs;
2669 int parse_hide_refs_config(const char *var, const char *value, const char *section)
2671 if (!strcmp("transfer.hiderefs", var) ||
2672 /* NEEDSWORK: use parse_config_key() once both are merged */
2673 (!prefixcmp(var, section) && var[strlen(section)] == '.' &&
2674 !strcmp(var + strlen(section), ".hiderefs"))) {
2675 char *ref;
2676 int len;
2678 if (!value)
2679 return config_error_nonbool(var);
2680 ref = xstrdup(value);
2681 len = strlen(ref);
2682 while (len && ref[len - 1] == '/')
2683 ref[--len] = '\0';
2684 if (!hide_refs) {
2685 hide_refs = xcalloc(1, sizeof(*hide_refs));
2686 hide_refs->strdup_strings = 1;
2688 string_list_append(hide_refs, ref);
2690 return 0;
2693 int ref_is_hidden(const char *refname)
2695 struct string_list_item *item;
2697 if (!hide_refs)
2698 return 0;
2699 for_each_string_list_item(item, hide_refs) {
2700 int len;
2701 if (prefixcmp(refname, item->string))
2702 continue;
2703 len = strlen(item->string);
2704 if (!refname[len] || refname[len] == '/')
2705 return 1;
2707 return 0;