Documentation/git.txt: update links to release notes
[git/haiku.git] / refs.c
blob24438c652fe4e09aaa1ba6dab283b8e59c24c1a7
1 #include "cache.h"
2 #include "refs.h"
3 #include "object.h"
4 #include "tag.h"
5 #include "dir.h"
7 /* ISSYMREF=01 and ISPACKED=02 are public interfaces */
8 #define REF_KNOWS_PEELED 04
10 struct ref_list {
11 struct ref_list *next;
12 unsigned char flag; /* ISSYMREF? ISPACKED? */
13 unsigned char sha1[20];
14 unsigned char peeled[20];
15 char name[FLEX_ARRAY];
18 static const char *parse_ref_line(char *line, unsigned char *sha1)
21 * 42: the answer to everything.
23 * In this case, it happens to be the answer to
24 * 40 (length of sha1 hex representation)
25 * +1 (space in between hex and name)
26 * +1 (newline at the end of the line)
28 int len = strlen(line) - 42;
30 if (len <= 0)
31 return NULL;
32 if (get_sha1_hex(line, sha1) < 0)
33 return NULL;
34 if (!isspace(line[40]))
35 return NULL;
36 line += 41;
37 if (isspace(*line))
38 return NULL;
39 if (line[len] != '\n')
40 return NULL;
41 line[len] = 0;
43 return line;
46 static struct ref_list *add_ref(const char *name, const unsigned char *sha1,
47 int flag, struct ref_list *list,
48 struct ref_list **new_entry)
50 int len;
51 struct ref_list *entry;
53 /* Allocate it and add it in.. */
54 len = strlen(name) + 1;
55 entry = xmalloc(sizeof(struct ref_list) + len);
56 hashcpy(entry->sha1, sha1);
57 hashclr(entry->peeled);
58 memcpy(entry->name, name, len);
59 entry->flag = flag;
60 entry->next = list;
61 if (new_entry)
62 *new_entry = entry;
63 return entry;
66 /* merge sort the ref list */
67 static struct ref_list *sort_ref_list(struct ref_list *list)
69 int psize, qsize, last_merge_count, cmp;
70 struct ref_list *p, *q, *l, *e;
71 struct ref_list *new_list = list;
72 int k = 1;
73 int merge_count = 0;
75 if (!list)
76 return list;
78 do {
79 last_merge_count = merge_count;
80 merge_count = 0;
82 psize = 0;
84 p = new_list;
85 q = new_list;
86 new_list = NULL;
87 l = NULL;
89 while (p) {
90 merge_count++;
92 while (psize < k && q->next) {
93 q = q->next;
94 psize++;
96 qsize = k;
98 while ((psize > 0) || (qsize > 0 && q)) {
99 if (qsize == 0 || !q) {
100 e = p;
101 p = p->next;
102 psize--;
103 } else if (psize == 0) {
104 e = q;
105 q = q->next;
106 qsize--;
107 } else {
108 cmp = strcmp(q->name, p->name);
109 if (cmp < 0) {
110 e = q;
111 q = q->next;
112 qsize--;
113 } else if (cmp > 0) {
114 e = p;
115 p = p->next;
116 psize--;
117 } else {
118 if (hashcmp(q->sha1, p->sha1))
119 die("Duplicated ref, and SHA1s don't match: %s",
120 q->name);
121 warning("Duplicated ref: %s", q->name);
122 e = q;
123 q = q->next;
124 qsize--;
125 free(e);
126 e = p;
127 p = p->next;
128 psize--;
132 e->next = NULL;
134 if (l)
135 l->next = e;
136 if (!new_list)
137 new_list = e;
138 l = e;
141 p = q;
144 k = k * 2;
145 } while ((last_merge_count != merge_count) || (last_merge_count != 1));
147 return new_list;
151 * Future: need to be in "struct repository"
152 * when doing a full libification.
154 static struct cached_refs {
155 char did_loose;
156 char did_packed;
157 struct ref_list *loose;
158 struct ref_list *packed;
159 } cached_refs;
160 static struct ref_list *current_ref;
162 static struct ref_list *extra_refs;
164 static void free_ref_list(struct ref_list *list)
166 struct ref_list *next;
167 for ( ; list; list = next) {
168 next = list->next;
169 free(list);
173 static void invalidate_cached_refs(void)
175 struct cached_refs *ca = &cached_refs;
177 if (ca->did_loose && ca->loose)
178 free_ref_list(ca->loose);
179 if (ca->did_packed && ca->packed)
180 free_ref_list(ca->packed);
181 ca->loose = ca->packed = NULL;
182 ca->did_loose = ca->did_packed = 0;
185 static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
187 struct ref_list *list = NULL;
188 struct ref_list *last = NULL;
189 char refline[PATH_MAX];
190 int flag = REF_ISPACKED;
192 while (fgets(refline, sizeof(refline), f)) {
193 unsigned char sha1[20];
194 const char *name;
195 static const char header[] = "# pack-refs with:";
197 if (!strncmp(refline, header, sizeof(header)-1)) {
198 const char *traits = refline + sizeof(header) - 1;
199 if (strstr(traits, " peeled "))
200 flag |= REF_KNOWS_PEELED;
201 /* perhaps other traits later as well */
202 continue;
205 name = parse_ref_line(refline, sha1);
206 if (name) {
207 list = add_ref(name, sha1, flag, list, &last);
208 continue;
210 if (last &&
211 refline[0] == '^' &&
212 strlen(refline) == 42 &&
213 refline[41] == '\n' &&
214 !get_sha1_hex(refline + 1, sha1))
215 hashcpy(last->peeled, sha1);
217 cached_refs->packed = sort_ref_list(list);
220 void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
222 extra_refs = add_ref(name, sha1, flag, extra_refs, NULL);
225 void clear_extra_refs(void)
227 free_ref_list(extra_refs);
228 extra_refs = NULL;
231 static struct ref_list *get_packed_refs(void)
233 if (!cached_refs.did_packed) {
234 FILE *f = fopen(git_path("packed-refs"), "r");
235 cached_refs.packed = NULL;
236 if (f) {
237 read_packed_refs(f, &cached_refs);
238 fclose(f);
240 cached_refs.did_packed = 1;
242 return cached_refs.packed;
245 static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
247 DIR *dir = opendir(git_path("%s", base));
249 if (dir) {
250 struct dirent *de;
251 int baselen = strlen(base);
252 char *ref = xmalloc(baselen + 257);
254 memcpy(ref, base, baselen);
255 if (baselen && base[baselen-1] != '/')
256 ref[baselen++] = '/';
258 while ((de = readdir(dir)) != NULL) {
259 unsigned char sha1[20];
260 struct stat st;
261 int flag;
262 int namelen;
264 if (de->d_name[0] == '.')
265 continue;
266 namelen = strlen(de->d_name);
267 if (namelen > 255)
268 continue;
269 if (has_extension(de->d_name, ".lock"))
270 continue;
271 memcpy(ref + baselen, de->d_name, namelen+1);
272 if (stat(git_path("%s", ref), &st) < 0)
273 continue;
274 if (S_ISDIR(st.st_mode)) {
275 list = get_ref_dir(ref, list);
276 continue;
278 if (!resolve_ref(ref, sha1, 1, &flag))
279 hashclr(sha1);
280 list = add_ref(ref, sha1, flag, list, NULL);
282 free(ref);
283 closedir(dir);
285 return sort_ref_list(list);
288 struct warn_if_dangling_data {
289 const char *refname;
290 const char *msg_fmt;
293 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
294 int flags, void *cb_data)
296 struct warn_if_dangling_data *d = cb_data;
297 const char *resolves_to;
298 unsigned char junk[20];
300 if (!(flags & REF_ISSYMREF))
301 return 0;
303 resolves_to = resolve_ref(refname, junk, 0, NULL);
304 if (!resolves_to || strcmp(resolves_to, d->refname))
305 return 0;
307 printf(d->msg_fmt, refname);
308 return 0;
311 void warn_dangling_symref(const char *msg_fmt, const char *refname)
313 struct warn_if_dangling_data data = { refname, msg_fmt };
314 for_each_rawref(warn_if_dangling_symref, &data);
317 static struct ref_list *get_loose_refs(void)
319 if (!cached_refs.did_loose) {
320 cached_refs.loose = get_ref_dir("refs", NULL);
321 cached_refs.did_loose = 1;
323 return cached_refs.loose;
326 /* We allow "recursive" symbolic refs. Only within reason, though */
327 #define MAXDEPTH 5
328 #define MAXREFLEN (1024)
330 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
332 FILE *f;
333 struct cached_refs refs;
334 struct ref_list *ref;
335 int retval;
337 strcpy(name + pathlen, "packed-refs");
338 f = fopen(name, "r");
339 if (!f)
340 return -1;
341 read_packed_refs(f, &refs);
342 fclose(f);
343 ref = refs.packed;
344 retval = -1;
345 while (ref) {
346 if (!strcmp(ref->name, refname)) {
347 retval = 0;
348 memcpy(result, ref->sha1, 20);
349 break;
351 ref = ref->next;
353 free_ref_list(refs.packed);
354 return retval;
357 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
359 int fd, len = strlen(refname);
360 char buffer[128], *p;
362 if (recursion > MAXDEPTH || len > MAXREFLEN)
363 return -1;
364 memcpy(name + pathlen, refname, len+1);
365 fd = open(name, O_RDONLY);
366 if (fd < 0)
367 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
369 len = read(fd, buffer, sizeof(buffer)-1);
370 close(fd);
371 if (len < 0)
372 return -1;
373 while (len && isspace(buffer[len-1]))
374 len--;
375 buffer[len] = 0;
377 /* Was it a detached head or an old-fashioned symlink? */
378 if (!get_sha1_hex(buffer, result))
379 return 0;
381 /* Symref? */
382 if (strncmp(buffer, "ref:", 4))
383 return -1;
384 p = buffer + 4;
385 while (isspace(*p))
386 p++;
388 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
391 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
393 int len = strlen(path), retval;
394 char *gitdir;
395 const char *tmp;
397 while (len && path[len-1] == '/')
398 len--;
399 if (!len)
400 return -1;
401 gitdir = xmalloc(len + MAXREFLEN + 8);
402 memcpy(gitdir, path, len);
403 memcpy(gitdir + len, "/.git", 6);
404 len += 5;
406 tmp = read_gitfile_gently(gitdir);
407 if (tmp) {
408 free(gitdir);
409 len = strlen(tmp);
410 gitdir = xmalloc(len + MAXREFLEN + 3);
411 memcpy(gitdir, tmp, len);
413 gitdir[len] = '/';
414 gitdir[++len] = '\0';
415 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
416 free(gitdir);
417 return retval;
421 * If the "reading" argument is set, this function finds out what _object_
422 * the ref points at by "reading" the ref. The ref, if it is not symbolic,
423 * has to exist, and if it is symbolic, it has to point at an existing ref,
424 * because the "read" goes through the symref to the ref it points at.
426 * The access that is not "reading" may often be "writing", but does not
427 * have to; it can be merely checking _where it leads to_. If it is a
428 * prelude to "writing" to the ref, a write to a symref that points at
429 * yet-to-be-born ref will create the real ref pointed by the symref.
430 * reading=0 allows the caller to check where such a symref leads to.
432 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
434 int depth = MAXDEPTH;
435 ssize_t len;
436 char buffer[256];
437 static char ref_buffer[256];
439 if (flag)
440 *flag = 0;
442 for (;;) {
443 char path[PATH_MAX];
444 struct stat st;
445 char *buf;
446 int fd;
448 if (--depth < 0)
449 return NULL;
451 git_snpath(path, sizeof(path), "%s", ref);
452 /* Special case: non-existing file. */
453 if (lstat(path, &st) < 0) {
454 struct ref_list *list = get_packed_refs();
455 while (list) {
456 if (!strcmp(ref, list->name)) {
457 hashcpy(sha1, list->sha1);
458 if (flag)
459 *flag |= REF_ISPACKED;
460 return ref;
462 list = list->next;
464 if (reading || errno != ENOENT)
465 return NULL;
466 hashclr(sha1);
467 return ref;
470 /* Follow "normalized" - ie "refs/.." symlinks by hand */
471 if (S_ISLNK(st.st_mode)) {
472 len = readlink(path, buffer, sizeof(buffer)-1);
473 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
474 buffer[len] = 0;
475 strcpy(ref_buffer, buffer);
476 ref = ref_buffer;
477 if (flag)
478 *flag |= REF_ISSYMREF;
479 continue;
483 /* Is it a directory? */
484 if (S_ISDIR(st.st_mode)) {
485 errno = EISDIR;
486 return NULL;
490 * Anything else, just open it and try to use it as
491 * a ref
493 fd = open(path, O_RDONLY);
494 if (fd < 0)
495 return NULL;
496 len = read_in_full(fd, buffer, sizeof(buffer)-1);
497 close(fd);
500 * Is it a symbolic ref?
502 if (len < 4 || memcmp("ref:", buffer, 4))
503 break;
504 buf = buffer + 4;
505 len -= 4;
506 while (len && isspace(*buf))
507 buf++, len--;
508 while (len && isspace(buf[len-1]))
509 len--;
510 buf[len] = 0;
511 memcpy(ref_buffer, buf, len + 1);
512 ref = ref_buffer;
513 if (flag)
514 *flag |= REF_ISSYMREF;
516 if (len < 40 || get_sha1_hex(buffer, sha1))
517 return NULL;
518 return ref;
521 int read_ref(const char *ref, unsigned char *sha1)
523 if (resolve_ref(ref, sha1, 1, NULL))
524 return 0;
525 return -1;
528 #define DO_FOR_EACH_INCLUDE_BROKEN 01
529 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
530 int flags, void *cb_data, struct ref_list *entry)
532 if (strncmp(base, entry->name, trim))
533 return 0;
534 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
535 if (is_null_sha1(entry->sha1))
536 return 0;
537 if (!has_sha1_file(entry->sha1)) {
538 error("%s does not point to a valid object!", entry->name);
539 return 0;
542 current_ref = entry;
543 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
546 int peel_ref(const char *ref, unsigned char *sha1)
548 int flag;
549 unsigned char base[20];
550 struct object *o;
552 if (current_ref && (current_ref->name == ref
553 || !strcmp(current_ref->name, ref))) {
554 if (current_ref->flag & REF_KNOWS_PEELED) {
555 hashcpy(sha1, current_ref->peeled);
556 return 0;
558 hashcpy(base, current_ref->sha1);
559 goto fallback;
562 if (!resolve_ref(ref, base, 1, &flag))
563 return -1;
565 if ((flag & REF_ISPACKED)) {
566 struct ref_list *list = get_packed_refs();
568 while (list) {
569 if (!strcmp(list->name, ref)) {
570 if (list->flag & REF_KNOWS_PEELED) {
571 hashcpy(sha1, list->peeled);
572 return 0;
574 /* older pack-refs did not leave peeled ones */
575 break;
577 list = list->next;
581 fallback:
582 o = parse_object(base);
583 if (o && o->type == OBJ_TAG) {
584 o = deref_tag(o, ref, 0);
585 if (o) {
586 hashcpy(sha1, o->sha1);
587 return 0;
590 return -1;
593 static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
594 int flags, void *cb_data)
596 int retval = 0;
597 struct ref_list *packed = get_packed_refs();
598 struct ref_list *loose = get_loose_refs();
600 struct ref_list *extra;
602 for (extra = extra_refs; extra; extra = extra->next)
603 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
605 while (packed && loose) {
606 struct ref_list *entry;
607 int cmp = strcmp(packed->name, loose->name);
608 if (!cmp) {
609 packed = packed->next;
610 continue;
612 if (cmp > 0) {
613 entry = loose;
614 loose = loose->next;
615 } else {
616 entry = packed;
617 packed = packed->next;
619 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
620 if (retval)
621 goto end_each;
624 for (packed = packed ? packed : loose; packed; packed = packed->next) {
625 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
626 if (retval)
627 goto end_each;
630 end_each:
631 current_ref = NULL;
632 return retval;
635 int head_ref(each_ref_fn fn, void *cb_data)
637 unsigned char sha1[20];
638 int flag;
640 if (resolve_ref("HEAD", sha1, 1, &flag))
641 return fn("HEAD", sha1, flag, cb_data);
642 return 0;
645 int for_each_ref(each_ref_fn fn, void *cb_data)
647 return do_for_each_ref("refs/", fn, 0, 0, cb_data);
650 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
652 return do_for_each_ref(prefix, fn, strlen(prefix), 0, cb_data);
655 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
657 return for_each_ref_in("refs/tags/", fn, cb_data);
660 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
662 return for_each_ref_in("refs/heads/", fn, cb_data);
665 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
667 return for_each_ref_in("refs/remotes/", fn, cb_data);
670 int for_each_rawref(each_ref_fn fn, void *cb_data)
672 return do_for_each_ref("refs/", fn, 0,
673 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
677 * Make sure "ref" is something reasonable to have under ".git/refs/";
678 * We do not like it if:
680 * - any path component of it begins with ".", or
681 * - it has double dots "..", or
682 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
683 * - it ends with a "/".
684 * - it ends with ".lock"
685 * - it contains a "\" (backslash)
688 static inline int bad_ref_char(int ch)
690 if (((unsigned) ch) <= ' ' ||
691 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
692 return 1;
693 /* 2.13 Pattern Matching Notation */
694 if (ch == '?' || ch == '[') /* Unsupported */
695 return 1;
696 if (ch == '*') /* Supported at the end */
697 return 2;
698 return 0;
701 int check_ref_format(const char *ref)
703 int ch, level, bad_type, last;
704 int ret = CHECK_REF_FORMAT_OK;
705 const char *cp = ref;
707 level = 0;
708 while (1) {
709 while ((ch = *cp++) == '/')
710 ; /* tolerate duplicated slashes */
711 if (!ch)
712 /* should not end with slashes */
713 return CHECK_REF_FORMAT_ERROR;
715 /* we are at the beginning of the path component */
716 if (ch == '.')
717 return CHECK_REF_FORMAT_ERROR;
718 bad_type = bad_ref_char(ch);
719 if (bad_type) {
720 if (bad_type == 2 && (!*cp || *cp == '/') &&
721 ret == CHECK_REF_FORMAT_OK)
722 ret = CHECK_REF_FORMAT_WILDCARD;
723 else
724 return CHECK_REF_FORMAT_ERROR;
727 last = ch;
728 /* scan the rest of the path component */
729 while ((ch = *cp++) != 0) {
730 bad_type = bad_ref_char(ch);
731 if (bad_type)
732 return CHECK_REF_FORMAT_ERROR;
733 if (ch == '/')
734 break;
735 if (last == '.' && ch == '.')
736 return CHECK_REF_FORMAT_ERROR;
737 if (last == '@' && ch == '{')
738 return CHECK_REF_FORMAT_ERROR;
739 last = ch;
741 level++;
742 if (!ch) {
743 if (ref <= cp - 2 && cp[-2] == '.')
744 return CHECK_REF_FORMAT_ERROR;
745 if (level < 2)
746 return CHECK_REF_FORMAT_ONELEVEL;
747 if (has_extension(ref, ".lock"))
748 return CHECK_REF_FORMAT_ERROR;
749 return ret;
754 const char *prettify_refname(const char *name)
756 return name + (
757 !prefixcmp(name, "refs/heads/") ? 11 :
758 !prefixcmp(name, "refs/tags/") ? 10 :
759 !prefixcmp(name, "refs/remotes/") ? 13 :
763 const char *ref_rev_parse_rules[] = {
764 "%.*s",
765 "refs/%.*s",
766 "refs/tags/%.*s",
767 "refs/heads/%.*s",
768 "refs/remotes/%.*s",
769 "refs/remotes/%.*s/HEAD",
770 NULL
773 const char *ref_fetch_rules[] = {
774 "%.*s",
775 "refs/%.*s",
776 "refs/heads/%.*s",
777 NULL
780 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
782 const char **p;
783 const int abbrev_name_len = strlen(abbrev_name);
785 for (p = rules; *p; p++) {
786 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
787 return 1;
791 return 0;
794 static struct ref_lock *verify_lock(struct ref_lock *lock,
795 const unsigned char *old_sha1, int mustexist)
797 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
798 error("Can't verify ref %s", lock->ref_name);
799 unlock_ref(lock);
800 return NULL;
802 if (hashcmp(lock->old_sha1, old_sha1)) {
803 error("Ref %s is at %s but expected %s", lock->ref_name,
804 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
805 unlock_ref(lock);
806 return NULL;
808 return lock;
811 static int remove_empty_directories(const char *file)
813 /* we want to create a file but there is a directory there;
814 * if that is an empty directory (or a directory that contains
815 * only empty directories), remove them.
817 struct strbuf path;
818 int result;
820 strbuf_init(&path, 20);
821 strbuf_addstr(&path, file);
823 result = remove_dir_recursively(&path, 1);
825 strbuf_release(&path);
827 return result;
830 static int is_refname_available(const char *ref, const char *oldref,
831 struct ref_list *list, int quiet)
833 int namlen = strlen(ref); /* e.g. 'foo/bar' */
834 while (list) {
835 /* list->name could be 'foo' or 'foo/bar/baz' */
836 if (!oldref || strcmp(oldref, list->name)) {
837 int len = strlen(list->name);
838 int cmplen = (namlen < len) ? namlen : len;
839 const char *lead = (namlen < len) ? list->name : ref;
840 if (!strncmp(ref, list->name, cmplen) &&
841 lead[cmplen] == '/') {
842 if (!quiet)
843 error("'%s' exists; cannot create '%s'",
844 list->name, ref);
845 return 0;
848 list = list->next;
850 return 1;
853 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
855 char *ref_file;
856 const char *orig_ref = ref;
857 struct ref_lock *lock;
858 int last_errno = 0;
859 int type, lflags;
860 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
861 int missing = 0;
863 lock = xcalloc(1, sizeof(struct ref_lock));
864 lock->lock_fd = -1;
866 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
867 if (!ref && errno == EISDIR) {
868 /* we are trying to lock foo but we used to
869 * have foo/bar which now does not exist;
870 * it is normal for the empty directory 'foo'
871 * to remain.
873 ref_file = git_path("%s", orig_ref);
874 if (remove_empty_directories(ref_file)) {
875 last_errno = errno;
876 error("there are still refs under '%s'", orig_ref);
877 goto error_return;
879 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
881 if (type_p)
882 *type_p = type;
883 if (!ref) {
884 last_errno = errno;
885 error("unable to resolve reference %s: %s",
886 orig_ref, strerror(errno));
887 goto error_return;
889 missing = is_null_sha1(lock->old_sha1);
890 /* When the ref did not exist and we are creating it,
891 * make sure there is no existing ref that is packed
892 * whose name begins with our refname, nor a ref whose
893 * name is a proper prefix of our refname.
895 if (missing &&
896 !is_refname_available(ref, NULL, get_packed_refs(), 0)) {
897 last_errno = ENOTDIR;
898 goto error_return;
901 lock->lk = xcalloc(1, sizeof(struct lock_file));
903 lflags = LOCK_DIE_ON_ERROR;
904 if (flags & REF_NODEREF) {
905 ref = orig_ref;
906 lflags |= LOCK_NODEREF;
908 lock->ref_name = xstrdup(ref);
909 lock->orig_ref_name = xstrdup(orig_ref);
910 ref_file = git_path("%s", ref);
911 if (missing)
912 lock->force_write = 1;
913 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
914 lock->force_write = 1;
916 if (safe_create_leading_directories(ref_file)) {
917 last_errno = errno;
918 error("unable to create directory for %s", ref_file);
919 goto error_return;
922 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
923 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
925 error_return:
926 unlock_ref(lock);
927 errno = last_errno;
928 return NULL;
931 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
933 char refpath[PATH_MAX];
934 if (check_ref_format(ref))
935 return NULL;
936 strcpy(refpath, mkpath("refs/%s", ref));
937 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
940 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
942 switch (check_ref_format(ref)) {
943 default:
944 return NULL;
945 case 0:
946 case CHECK_REF_FORMAT_ONELEVEL:
947 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
951 static struct lock_file packlock;
953 static int repack_without_ref(const char *refname)
955 struct ref_list *list, *packed_ref_list;
956 int fd;
957 int found = 0;
959 packed_ref_list = get_packed_refs();
960 for (list = packed_ref_list; list; list = list->next) {
961 if (!strcmp(refname, list->name)) {
962 found = 1;
963 break;
966 if (!found)
967 return 0;
968 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
969 if (fd < 0)
970 return error("cannot delete '%s' from packed refs", refname);
972 for (list = packed_ref_list; list; list = list->next) {
973 char line[PATH_MAX + 100];
974 int len;
976 if (!strcmp(refname, list->name))
977 continue;
978 len = snprintf(line, sizeof(line), "%s %s\n",
979 sha1_to_hex(list->sha1), list->name);
980 /* this should not happen but just being defensive */
981 if (len > sizeof(line))
982 die("too long a refname '%s'", list->name);
983 write_or_die(fd, line, len);
985 return commit_lock_file(&packlock);
988 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
990 struct ref_lock *lock;
991 int err, i = 0, ret = 0, flag = 0;
993 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
994 if (!lock)
995 return 1;
996 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
997 /* loose */
998 const char *path;
1000 if (!(delopt & REF_NODEREF)) {
1001 i = strlen(lock->lk->filename) - 5; /* .lock */
1002 lock->lk->filename[i] = 0;
1003 path = lock->lk->filename;
1004 } else {
1005 path = git_path("%s", refname);
1007 err = unlink_or_warn(path);
1008 if (err && errno != ENOENT)
1009 ret = 1;
1011 if (!(delopt & REF_NODEREF))
1012 lock->lk->filename[i] = '.';
1014 /* removing the loose one could have resurrected an earlier
1015 * packed one. Also, if it was not loose we need to repack
1016 * without it.
1018 ret |= repack_without_ref(refname);
1020 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1021 invalidate_cached_refs();
1022 unlock_ref(lock);
1023 return ret;
1026 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1028 static const char renamed_ref[] = "RENAMED-REF";
1029 unsigned char sha1[20], orig_sha1[20];
1030 int flag = 0, logmoved = 0;
1031 struct ref_lock *lock;
1032 struct stat loginfo;
1033 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1034 const char *symref = NULL;
1036 if (log && S_ISLNK(loginfo.st_mode))
1037 return error("reflog for %s is a symlink", oldref);
1039 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1040 if (flag & REF_ISSYMREF)
1041 return error("refname %s is a symbolic ref, renaming it is not supported",
1042 oldref);
1043 if (!symref)
1044 return error("refname %s not found", oldref);
1046 if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
1047 return 1;
1049 if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
1050 return 1;
1052 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
1053 if (!lock)
1054 return error("unable to lock %s", renamed_ref);
1055 lock->force_write = 1;
1056 if (write_ref_sha1(lock, orig_sha1, logmsg))
1057 return error("unable to save current sha1 in %s", renamed_ref);
1059 if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
1060 return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
1061 oldref, strerror(errno));
1063 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1064 error("unable to delete old %s", oldref);
1065 goto rollback;
1068 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1069 if (errno==EISDIR) {
1070 if (remove_empty_directories(git_path("%s", newref))) {
1071 error("Directory not empty: %s", newref);
1072 goto rollback;
1074 } else {
1075 error("unable to delete existing %s", newref);
1076 goto rollback;
1080 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1081 error("unable to create directory for %s", newref);
1082 goto rollback;
1085 retry:
1086 if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
1087 if (errno==EISDIR || errno==ENOTDIR) {
1089 * rename(a, b) when b is an existing
1090 * directory ought to result in ISDIR, but
1091 * Solaris 5.8 gives ENOTDIR. Sheesh.
1093 if (remove_empty_directories(git_path("logs/%s", newref))) {
1094 error("Directory not empty: logs/%s", newref);
1095 goto rollback;
1097 goto retry;
1098 } else {
1099 error("unable to move logfile tmp-renamed-log to logs/%s: %s",
1100 newref, strerror(errno));
1101 goto rollback;
1104 logmoved = log;
1106 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1107 if (!lock) {
1108 error("unable to lock %s for update", newref);
1109 goto rollback;
1111 lock->force_write = 1;
1112 hashcpy(lock->old_sha1, orig_sha1);
1113 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1114 error("unable to write current sha1 into %s", newref);
1115 goto rollback;
1118 return 0;
1120 rollback:
1121 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1122 if (!lock) {
1123 error("unable to lock %s for rollback", oldref);
1124 goto rollbacklog;
1127 lock->force_write = 1;
1128 flag = log_all_ref_updates;
1129 log_all_ref_updates = 0;
1130 if (write_ref_sha1(lock, orig_sha1, NULL))
1131 error("unable to write current sha1 into %s", oldref);
1132 log_all_ref_updates = flag;
1134 rollbacklog:
1135 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1136 error("unable to restore logfile %s from %s: %s",
1137 oldref, newref, strerror(errno));
1138 if (!logmoved && log &&
1139 rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
1140 error("unable to restore logfile %s from tmp-renamed-log: %s",
1141 oldref, strerror(errno));
1143 return 1;
1146 int close_ref(struct ref_lock *lock)
1148 if (close_lock_file(lock->lk))
1149 return -1;
1150 lock->lock_fd = -1;
1151 return 0;
1154 int commit_ref(struct ref_lock *lock)
1156 if (commit_lock_file(lock->lk))
1157 return -1;
1158 lock->lock_fd = -1;
1159 return 0;
1162 void unlock_ref(struct ref_lock *lock)
1164 /* Do not free lock->lk -- atexit() still looks at them */
1165 if (lock->lk)
1166 rollback_lock_file(lock->lk);
1167 free(lock->ref_name);
1168 free(lock->orig_ref_name);
1169 free(lock);
1173 * copy the reflog message msg to buf, which has been allocated sufficiently
1174 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1175 * because reflog file is one line per entry.
1177 static int copy_msg(char *buf, const char *msg)
1179 char *cp = buf;
1180 char c;
1181 int wasspace = 1;
1183 *cp++ = '\t';
1184 while ((c = *msg++)) {
1185 if (wasspace && isspace(c))
1186 continue;
1187 wasspace = isspace(c);
1188 if (wasspace)
1189 c = ' ';
1190 *cp++ = c;
1192 while (buf < cp && isspace(cp[-1]))
1193 cp--;
1194 *cp++ = '\n';
1195 return cp - buf;
1198 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1199 const unsigned char *new_sha1, const char *msg)
1201 int logfd, written, oflags = O_APPEND | O_WRONLY;
1202 unsigned maxlen, len;
1203 int msglen;
1204 char log_file[PATH_MAX];
1205 char *logrec;
1206 const char *committer;
1208 if (log_all_ref_updates < 0)
1209 log_all_ref_updates = !is_bare_repository();
1211 git_snpath(log_file, sizeof(log_file), "logs/%s", ref_name);
1213 if (log_all_ref_updates &&
1214 (!prefixcmp(ref_name, "refs/heads/") ||
1215 !prefixcmp(ref_name, "refs/remotes/") ||
1216 !strcmp(ref_name, "HEAD"))) {
1217 if (safe_create_leading_directories(log_file) < 0)
1218 return error("unable to create directory for %s",
1219 log_file);
1220 oflags |= O_CREAT;
1223 logfd = open(log_file, oflags, 0666);
1224 if (logfd < 0) {
1225 if (!(oflags & O_CREAT) && errno == ENOENT)
1226 return 0;
1228 if ((oflags & O_CREAT) && errno == EISDIR) {
1229 if (remove_empty_directories(log_file)) {
1230 return error("There are still logs under '%s'",
1231 log_file);
1233 logfd = open(log_file, oflags, 0666);
1236 if (logfd < 0)
1237 return error("Unable to append to %s: %s",
1238 log_file, strerror(errno));
1241 adjust_shared_perm(log_file);
1243 msglen = msg ? strlen(msg) : 0;
1244 committer = git_committer_info(0);
1245 maxlen = strlen(committer) + msglen + 100;
1246 logrec = xmalloc(maxlen);
1247 len = sprintf(logrec, "%s %s %s\n",
1248 sha1_to_hex(old_sha1),
1249 sha1_to_hex(new_sha1),
1250 committer);
1251 if (msglen)
1252 len += copy_msg(logrec + len - 1, msg) - 1;
1253 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1254 free(logrec);
1255 if (close(logfd) != 0 || written != len)
1256 return error("Unable to append to %s", log_file);
1257 return 0;
1260 static int is_branch(const char *refname)
1262 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1265 int write_ref_sha1(struct ref_lock *lock,
1266 const unsigned char *sha1, const char *logmsg)
1268 static char term = '\n';
1269 struct object *o;
1271 if (!lock)
1272 return -1;
1273 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1274 unlock_ref(lock);
1275 return 0;
1277 o = parse_object(sha1);
1278 if (!o) {
1279 error("Trying to write ref %s with nonexistant object %s",
1280 lock->ref_name, sha1_to_hex(sha1));
1281 unlock_ref(lock);
1282 return -1;
1284 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1285 error("Trying to write non-commit object %s to branch %s",
1286 sha1_to_hex(sha1), lock->ref_name);
1287 unlock_ref(lock);
1288 return -1;
1290 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1291 write_in_full(lock->lock_fd, &term, 1) != 1
1292 || close_ref(lock) < 0) {
1293 error("Couldn't write %s", lock->lk->filename);
1294 unlock_ref(lock);
1295 return -1;
1297 invalidate_cached_refs();
1298 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1299 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1300 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1301 unlock_ref(lock);
1302 return -1;
1304 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1306 * Special hack: If a branch is updated directly and HEAD
1307 * points to it (may happen on the remote side of a push
1308 * for example) then logically the HEAD reflog should be
1309 * updated too.
1310 * A generic solution implies reverse symref information,
1311 * but finding all symrefs pointing to the given branch
1312 * would be rather costly for this rare event (the direct
1313 * update of a branch) to be worth it. So let's cheat and
1314 * check with HEAD only which should cover 99% of all usage
1315 * scenarios (even 100% of the default ones).
1317 unsigned char head_sha1[20];
1318 int head_flag;
1319 const char *head_ref;
1320 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1321 if (head_ref && (head_flag & REF_ISSYMREF) &&
1322 !strcmp(head_ref, lock->ref_name))
1323 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1325 if (commit_ref(lock)) {
1326 error("Couldn't set %s", lock->ref_name);
1327 unlock_ref(lock);
1328 return -1;
1330 unlock_ref(lock);
1331 return 0;
1334 int create_symref(const char *ref_target, const char *refs_heads_master,
1335 const char *logmsg)
1337 const char *lockpath;
1338 char ref[1000];
1339 int fd, len, written;
1340 char *git_HEAD = git_pathdup("%s", ref_target);
1341 unsigned char old_sha1[20], new_sha1[20];
1343 if (logmsg && read_ref(ref_target, old_sha1))
1344 hashclr(old_sha1);
1346 if (safe_create_leading_directories(git_HEAD) < 0)
1347 return error("unable to create directory for %s", git_HEAD);
1349 #ifndef NO_SYMLINK_HEAD
1350 if (prefer_symlink_refs) {
1351 unlink(git_HEAD);
1352 if (!symlink(refs_heads_master, git_HEAD))
1353 goto done;
1354 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1356 #endif
1358 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1359 if (sizeof(ref) <= len) {
1360 error("refname too long: %s", refs_heads_master);
1361 goto error_free_return;
1363 lockpath = mkpath("%s.lock", git_HEAD);
1364 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1365 if (fd < 0) {
1366 error("Unable to open %s for writing", lockpath);
1367 goto error_free_return;
1369 written = write_in_full(fd, ref, len);
1370 if (close(fd) != 0 || written != len) {
1371 error("Unable to write to %s", lockpath);
1372 goto error_unlink_return;
1374 if (rename(lockpath, git_HEAD) < 0) {
1375 error("Unable to create %s", git_HEAD);
1376 goto error_unlink_return;
1378 if (adjust_shared_perm(git_HEAD)) {
1379 error("Unable to fix permissions on %s", lockpath);
1380 error_unlink_return:
1381 unlink_or_warn(lockpath);
1382 error_free_return:
1383 free(git_HEAD);
1384 return -1;
1387 #ifndef NO_SYMLINK_HEAD
1388 done:
1389 #endif
1390 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1391 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1393 free(git_HEAD);
1394 return 0;
1397 static char *ref_msg(const char *line, const char *endp)
1399 const char *ep;
1400 line += 82;
1401 ep = memchr(line, '\n', endp - line);
1402 if (!ep)
1403 ep = endp;
1404 return xmemdupz(line, ep - line);
1407 int read_ref_at(const char *ref, unsigned long at_time, int cnt, unsigned char *sha1, char **msg, unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
1409 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1410 char *tz_c;
1411 int logfd, tz, reccnt = 0;
1412 struct stat st;
1413 unsigned long date;
1414 unsigned char logged_sha1[20];
1415 void *log_mapped;
1416 size_t mapsz;
1418 logfile = git_path("logs/%s", ref);
1419 logfd = open(logfile, O_RDONLY, 0);
1420 if (logfd < 0)
1421 die("Unable to read log %s: %s", logfile, strerror(errno));
1422 fstat(logfd, &st);
1423 if (!st.st_size)
1424 die("Log %s is empty.", logfile);
1425 mapsz = xsize_t(st.st_size);
1426 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1427 logdata = log_mapped;
1428 close(logfd);
1430 lastrec = NULL;
1431 rec = logend = logdata + st.st_size;
1432 while (logdata < rec) {
1433 reccnt++;
1434 if (logdata < rec && *(rec-1) == '\n')
1435 rec--;
1436 lastgt = NULL;
1437 while (logdata < rec && *(rec-1) != '\n') {
1438 rec--;
1439 if (*rec == '>')
1440 lastgt = rec;
1442 if (!lastgt)
1443 die("Log %s is corrupt.", logfile);
1444 date = strtoul(lastgt + 1, &tz_c, 10);
1445 if (date <= at_time || cnt == 0) {
1446 tz = strtoul(tz_c, NULL, 10);
1447 if (msg)
1448 *msg = ref_msg(rec, logend);
1449 if (cutoff_time)
1450 *cutoff_time = date;
1451 if (cutoff_tz)
1452 *cutoff_tz = tz;
1453 if (cutoff_cnt)
1454 *cutoff_cnt = reccnt - 1;
1455 if (lastrec) {
1456 if (get_sha1_hex(lastrec, logged_sha1))
1457 die("Log %s is corrupt.", logfile);
1458 if (get_sha1_hex(rec + 41, sha1))
1459 die("Log %s is corrupt.", logfile);
1460 if (hashcmp(logged_sha1, sha1)) {
1461 warning("Log %s has gap after %s.",
1462 logfile, show_date(date, tz, DATE_RFC2822));
1465 else if (date == at_time) {
1466 if (get_sha1_hex(rec + 41, sha1))
1467 die("Log %s is corrupt.", logfile);
1469 else {
1470 if (get_sha1_hex(rec + 41, logged_sha1))
1471 die("Log %s is corrupt.", logfile);
1472 if (hashcmp(logged_sha1, sha1)) {
1473 warning("Log %s unexpectedly ended on %s.",
1474 logfile, show_date(date, tz, DATE_RFC2822));
1477 munmap(log_mapped, mapsz);
1478 return 0;
1480 lastrec = rec;
1481 if (cnt > 0)
1482 cnt--;
1485 rec = logdata;
1486 while (rec < logend && *rec != '>' && *rec != '\n')
1487 rec++;
1488 if (rec == logend || *rec == '\n')
1489 die("Log %s is corrupt.", logfile);
1490 date = strtoul(rec + 1, &tz_c, 10);
1491 tz = strtoul(tz_c, NULL, 10);
1492 if (get_sha1_hex(logdata, sha1))
1493 die("Log %s is corrupt.", logfile);
1494 if (is_null_sha1(sha1)) {
1495 if (get_sha1_hex(logdata + 41, sha1))
1496 die("Log %s is corrupt.", logfile);
1498 if (msg)
1499 *msg = ref_msg(logdata, logend);
1500 munmap(log_mapped, mapsz);
1502 if (cutoff_time)
1503 *cutoff_time = date;
1504 if (cutoff_tz)
1505 *cutoff_tz = tz;
1506 if (cutoff_cnt)
1507 *cutoff_cnt = reccnt;
1508 return 1;
1511 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1513 const char *logfile;
1514 FILE *logfp;
1515 char buf[1024];
1516 int ret = 0;
1518 logfile = git_path("logs/%s", ref);
1519 logfp = fopen(logfile, "r");
1520 if (!logfp)
1521 return -1;
1523 if (ofs) {
1524 struct stat statbuf;
1525 if (fstat(fileno(logfp), &statbuf) ||
1526 statbuf.st_size < ofs ||
1527 fseek(logfp, -ofs, SEEK_END) ||
1528 fgets(buf, sizeof(buf), logfp))
1529 return -1;
1532 while (fgets(buf, sizeof(buf), logfp)) {
1533 unsigned char osha1[20], nsha1[20];
1534 char *email_end, *message;
1535 unsigned long timestamp;
1536 int len, tz;
1538 /* old SP new SP name <email> SP time TAB msg LF */
1539 len = strlen(buf);
1540 if (len < 83 || buf[len-1] != '\n' ||
1541 get_sha1_hex(buf, osha1) || buf[40] != ' ' ||
1542 get_sha1_hex(buf + 41, nsha1) || buf[81] != ' ' ||
1543 !(email_end = strchr(buf + 82, '>')) ||
1544 email_end[1] != ' ' ||
1545 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1546 !message || message[0] != ' ' ||
1547 (message[1] != '+' && message[1] != '-') ||
1548 !isdigit(message[2]) || !isdigit(message[3]) ||
1549 !isdigit(message[4]) || !isdigit(message[5]))
1550 continue; /* corrupt? */
1551 email_end[1] = '\0';
1552 tz = strtol(message + 1, NULL, 10);
1553 if (message[6] != '\t')
1554 message += 6;
1555 else
1556 message += 7;
1557 ret = fn(osha1, nsha1, buf+82, timestamp, tz, message, cb_data);
1558 if (ret)
1559 break;
1561 fclose(logfp);
1562 return ret;
1565 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1567 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1570 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1572 DIR *dir = opendir(git_path("logs/%s", base));
1573 int retval = 0;
1575 if (dir) {
1576 struct dirent *de;
1577 int baselen = strlen(base);
1578 char *log = xmalloc(baselen + 257);
1580 memcpy(log, base, baselen);
1581 if (baselen && base[baselen-1] != '/')
1582 log[baselen++] = '/';
1584 while ((de = readdir(dir)) != NULL) {
1585 struct stat st;
1586 int namelen;
1588 if (de->d_name[0] == '.')
1589 continue;
1590 namelen = strlen(de->d_name);
1591 if (namelen > 255)
1592 continue;
1593 if (has_extension(de->d_name, ".lock"))
1594 continue;
1595 memcpy(log + baselen, de->d_name, namelen+1);
1596 if (stat(git_path("logs/%s", log), &st) < 0)
1597 continue;
1598 if (S_ISDIR(st.st_mode)) {
1599 retval = do_for_each_reflog(log, fn, cb_data);
1600 } else {
1601 unsigned char sha1[20];
1602 if (!resolve_ref(log, sha1, 0, NULL))
1603 retval = error("bad ref for %s", log);
1604 else
1605 retval = fn(log, sha1, 0, cb_data);
1607 if (retval)
1608 break;
1610 free(log);
1611 closedir(dir);
1613 else if (*base)
1614 return errno;
1615 return retval;
1618 int for_each_reflog(each_ref_fn fn, void *cb_data)
1620 return do_for_each_reflog("", fn, cb_data);
1623 int update_ref(const char *action, const char *refname,
1624 const unsigned char *sha1, const unsigned char *oldval,
1625 int flags, enum action_on_err onerr)
1627 static struct ref_lock *lock;
1628 lock = lock_any_ref_for_update(refname, oldval, flags);
1629 if (!lock) {
1630 const char *str = "Cannot lock the ref '%s'.";
1631 switch (onerr) {
1632 case MSG_ON_ERR: error(str, refname); break;
1633 case DIE_ON_ERR: die(str, refname); break;
1634 case QUIET_ON_ERR: break;
1636 return 1;
1638 if (write_ref_sha1(lock, sha1, action) < 0) {
1639 const char *str = "Cannot update the ref '%s'.";
1640 switch (onerr) {
1641 case MSG_ON_ERR: error(str, refname); break;
1642 case DIE_ON_ERR: die(str, refname); break;
1643 case QUIET_ON_ERR: break;
1645 return 1;
1647 return 0;
1650 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1652 for ( ; list; list = list->next)
1653 if (!strcmp(list->name, name))
1654 return (struct ref *)list;
1655 return NULL;
1659 * generate a format suitable for scanf from a ref_rev_parse_rules
1660 * rule, that is replace the "%.*s" spec with a "%s" spec
1662 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1664 char *spec;
1666 spec = strstr(rule, "%.*s");
1667 if (!spec || strstr(spec + 4, "%.*s"))
1668 die("invalid rule in ref_rev_parse_rules: %s", rule);
1670 /* copy all until spec */
1671 strncpy(scanf_fmt, rule, spec - rule);
1672 scanf_fmt[spec - rule] = '\0';
1673 /* copy new spec */
1674 strcat(scanf_fmt, "%s");
1675 /* copy remaining rule */
1676 strcat(scanf_fmt, spec + 4);
1678 return;
1681 char *shorten_unambiguous_ref(const char *ref, int strict)
1683 int i;
1684 static char **scanf_fmts;
1685 static int nr_rules;
1686 char *short_name;
1688 /* pre generate scanf formats from ref_rev_parse_rules[] */
1689 if (!nr_rules) {
1690 size_t total_len = 0;
1692 /* the rule list is NULL terminated, count them first */
1693 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1694 /* no +1 because strlen("%s") < strlen("%.*s") */
1695 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1697 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1699 total_len = 0;
1700 for (i = 0; i < nr_rules; i++) {
1701 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1702 + total_len;
1703 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1704 total_len += strlen(ref_rev_parse_rules[i]);
1708 /* bail out if there are no rules */
1709 if (!nr_rules)
1710 return xstrdup(ref);
1712 /* buffer for scanf result, at most ref must fit */
1713 short_name = xstrdup(ref);
1715 /* skip first rule, it will always match */
1716 for (i = nr_rules - 1; i > 0 ; --i) {
1717 int j;
1718 int rules_to_fail = i;
1719 int short_name_len;
1721 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1722 continue;
1724 short_name_len = strlen(short_name);
1727 * in strict mode, all (except the matched one) rules
1728 * must fail to resolve to a valid non-ambiguous ref
1730 if (strict)
1731 rules_to_fail = nr_rules;
1734 * check if the short name resolves to a valid ref,
1735 * but use only rules prior to the matched one
1737 for (j = 0; j < rules_to_fail; j++) {
1738 const char *rule = ref_rev_parse_rules[j];
1739 unsigned char short_objectname[20];
1740 char refname[PATH_MAX];
1742 /* skip matched rule */
1743 if (i == j)
1744 continue;
1747 * the short name is ambiguous, if it resolves
1748 * (with this previous rule) to a valid ref
1749 * read_ref() returns 0 on success
1751 mksnpath(refname, sizeof(refname),
1752 rule, short_name_len, short_name);
1753 if (!read_ref(refname, short_objectname))
1754 break;
1758 * short name is non-ambiguous if all previous rules
1759 * haven't resolved to a valid ref
1761 if (j == rules_to_fail)
1762 return short_name;
1765 free(short_name);
1766 return xstrdup(ref);