Merge branch 'lt/case-insensitive'
[git/git.git] / refs.c
1 #include "cache.h"
2 #include "refs.h"
3 #include "object.h"
4 #include "tag.h"
5 #include "dir.h"
6
7 /* ISSYMREF=01 and ISPACKED=02 are public interfaces */
8 #define REF_KNOWS_PEELED 04
9
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];
16 };
17
18 static const char *parse_ref_line(char *line, unsigned char *sha1)
19 {
20 /*
21 * 42: the answer to everything.
22 *
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)
27 */
28 int len = strlen(line) - 42;
29
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;
42
43 return line;
44 }
45
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)
49 {
50 int len;
51 struct ref_list *entry;
52
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;
64 }
65
66 /* merge sort the ref list */
67 static struct ref_list *sort_ref_list(struct ref_list *list)
68 {
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;
74
75 if (!list)
76 return list;
77
78 do {
79 last_merge_count = merge_count;
80 merge_count = 0;
81
82 psize = 0;
83
84 p = new_list;
85 q = new_list;
86 new_list = NULL;
87 l = NULL;
88
89 while (p) {
90 merge_count++;
91
92 while (psize < k && q->next) {
93 q = q->next;
94 psize++;
95 }
96 qsize = k;
97
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--;
129 }
130 }
131
132 e->next = NULL;
133
134 if (l)
135 l->next = e;
136 if (!new_list)
137 new_list = e;
138 l = e;
139 }
140
141 p = q;
142 };
143
144 k = k * 2;
145 } while ((last_merge_count != merge_count) || (last_merge_count != 1));
146
147 return new_list;
148 }
149
150 /*
151 * Future: need to be in "struct repository"
152 * when doing a full libification.
153 */
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;
161
162 static void free_ref_list(struct ref_list *list)
163 {
164 struct ref_list *next;
165 for ( ; list; list = next) {
166 next = list->next;
167 free(list);
168 }
169 }
170
171 static void invalidate_cached_refs(void)
172 {
173 struct cached_refs *ca = &cached_refs;
174
175 if (ca->did_loose && ca->loose)
176 free_ref_list(ca->loose);
177 if (ca->did_packed && ca->packed)
178 free_ref_list(ca->packed);
179 ca->loose = ca->packed = NULL;
180 ca->did_loose = ca->did_packed = 0;
181 }
182
183 static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
184 {
185 struct ref_list *list = NULL;
186 struct ref_list *last = NULL;
187 char refline[PATH_MAX];
188 int flag = REF_ISPACKED;
189
190 while (fgets(refline, sizeof(refline), f)) {
191 unsigned char sha1[20];
192 const char *name;
193 static const char header[] = "# pack-refs with:";
194
195 if (!strncmp(refline, header, sizeof(header)-1)) {
196 const char *traits = refline + sizeof(header) - 1;
197 if (strstr(traits, " peeled "))
198 flag |= REF_KNOWS_PEELED;
199 /* perhaps other traits later as well */
200 continue;
201 }
202
203 name = parse_ref_line(refline, sha1);
204 if (name) {
205 list = add_ref(name, sha1, flag, list, &last);
206 continue;
207 }
208 if (last &&
209 refline[0] == '^' &&
210 strlen(refline) == 42 &&
211 refline[41] == '\n' &&
212 !get_sha1_hex(refline + 1, sha1))
213 hashcpy(last->peeled, sha1);
214 }
215 cached_refs->packed = sort_ref_list(list);
216 }
217
218 static struct ref_list *get_packed_refs(void)
219 {
220 if (!cached_refs.did_packed) {
221 FILE *f = fopen(git_path("packed-refs"), "r");
222 cached_refs.packed = NULL;
223 if (f) {
224 read_packed_refs(f, &cached_refs);
225 fclose(f);
226 }
227 cached_refs.did_packed = 1;
228 }
229 return cached_refs.packed;
230 }
231
232 static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
233 {
234 DIR *dir = opendir(git_path("%s", base));
235
236 if (dir) {
237 struct dirent *de;
238 int baselen = strlen(base);
239 char *ref = xmalloc(baselen + 257);
240
241 memcpy(ref, base, baselen);
242 if (baselen && base[baselen-1] != '/')
243 ref[baselen++] = '/';
244
245 while ((de = readdir(dir)) != NULL) {
246 unsigned char sha1[20];
247 struct stat st;
248 int flag;
249 int namelen;
250
251 if (de->d_name[0] == '.')
252 continue;
253 namelen = strlen(de->d_name);
254 if (namelen > 255)
255 continue;
256 if (has_extension(de->d_name, ".lock"))
257 continue;
258 memcpy(ref + baselen, de->d_name, namelen+1);
259 if (stat(git_path("%s", ref), &st) < 0)
260 continue;
261 if (S_ISDIR(st.st_mode)) {
262 list = get_ref_dir(ref, list);
263 continue;
264 }
265 if (!resolve_ref(ref, sha1, 1, &flag)) {
266 error("%s points nowhere!", ref);
267 continue;
268 }
269 list = add_ref(ref, sha1, flag, list, NULL);
270 }
271 free(ref);
272 closedir(dir);
273 }
274 return sort_ref_list(list);
275 }
276
277 static struct ref_list *get_loose_refs(void)
278 {
279 if (!cached_refs.did_loose) {
280 cached_refs.loose = get_ref_dir("refs", NULL);
281 cached_refs.did_loose = 1;
282 }
283 return cached_refs.loose;
284 }
285
286 /* We allow "recursive" symbolic refs. Only within reason, though */
287 #define MAXDEPTH 5
288 #define MAXREFLEN (1024)
289
290 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
291 {
292 FILE *f;
293 struct cached_refs refs;
294 struct ref_list *ref;
295 int retval;
296
297 strcpy(name + pathlen, "packed-refs");
298 f = fopen(name, "r");
299 if (!f)
300 return -1;
301 read_packed_refs(f, &refs);
302 fclose(f);
303 ref = refs.packed;
304 retval = -1;
305 while (ref) {
306 if (!strcmp(ref->name, refname)) {
307 retval = 0;
308 memcpy(result, ref->sha1, 20);
309 break;
310 }
311 ref = ref->next;
312 }
313 free_ref_list(refs.packed);
314 return retval;
315 }
316
317 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
318 {
319 int fd, len = strlen(refname);
320 char buffer[128], *p;
321
322 if (recursion > MAXDEPTH || len > MAXREFLEN)
323 return -1;
324 memcpy(name + pathlen, refname, len+1);
325 fd = open(name, O_RDONLY);
326 if (fd < 0)
327 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
328
329 len = read(fd, buffer, sizeof(buffer)-1);
330 close(fd);
331 if (len < 0)
332 return -1;
333 while (len && isspace(buffer[len-1]))
334 len--;
335 buffer[len] = 0;
336
337 /* Was it a detached head or an old-fashioned symlink? */
338 if (!get_sha1_hex(buffer, result))
339 return 0;
340
341 /* Symref? */
342 if (strncmp(buffer, "ref:", 4))
343 return -1;
344 p = buffer + 4;
345 while (isspace(*p))
346 p++;
347
348 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
349 }
350
351 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
352 {
353 int len = strlen(path), retval;
354 char *gitdir;
355 const char *tmp;
356
357 while (len && path[len-1] == '/')
358 len--;
359 if (!len)
360 return -1;
361 gitdir = xmalloc(len + MAXREFLEN + 8);
362 memcpy(gitdir, path, len);
363 memcpy(gitdir + len, "/.git", 6);
364 len += 5;
365
366 tmp = read_gitfile_gently(gitdir);
367 if (tmp) {
368 free(gitdir);
369 len = strlen(tmp);
370 gitdir = xmalloc(len + MAXREFLEN + 3);
371 memcpy(gitdir, tmp, len);
372 }
373 gitdir[len] = '/';
374 gitdir[++len] = '\0';
375 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
376 free(gitdir);
377 return retval;
378 }
379
380 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
381 {
382 int depth = MAXDEPTH;
383 ssize_t len;
384 char buffer[256];
385 static char ref_buffer[256];
386
387 if (flag)
388 *flag = 0;
389
390 for (;;) {
391 const char *path = git_path("%s", ref);
392 struct stat st;
393 char *buf;
394 int fd;
395
396 if (--depth < 0)
397 return NULL;
398
399 /* Special case: non-existing file.
400 * Not having the refs/heads/new-branch is OK
401 * if we are writing into it, so is .git/HEAD
402 * that points at refs/heads/master still to be
403 * born. It is NOT OK if we are resolving for
404 * reading.
405 */
406 if (lstat(path, &st) < 0) {
407 struct ref_list *list = get_packed_refs();
408 while (list) {
409 if (!strcmp(ref, list->name)) {
410 hashcpy(sha1, list->sha1);
411 if (flag)
412 *flag |= REF_ISPACKED;
413 return ref;
414 }
415 list = list->next;
416 }
417 if (reading || errno != ENOENT)
418 return NULL;
419 hashclr(sha1);
420 return ref;
421 }
422
423 /* Follow "normalized" - ie "refs/.." symlinks by hand */
424 if (S_ISLNK(st.st_mode)) {
425 len = readlink(path, buffer, sizeof(buffer)-1);
426 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
427 buffer[len] = 0;
428 strcpy(ref_buffer, buffer);
429 ref = ref_buffer;
430 if (flag)
431 *flag |= REF_ISSYMREF;
432 continue;
433 }
434 }
435
436 /* Is it a directory? */
437 if (S_ISDIR(st.st_mode)) {
438 errno = EISDIR;
439 return NULL;
440 }
441
442 /*
443 * Anything else, just open it and try to use it as
444 * a ref
445 */
446 fd = open(path, O_RDONLY);
447 if (fd < 0)
448 return NULL;
449 len = read_in_full(fd, buffer, sizeof(buffer)-1);
450 close(fd);
451
452 /*
453 * Is it a symbolic ref?
454 */
455 if (len < 4 || memcmp("ref:", buffer, 4))
456 break;
457 buf = buffer + 4;
458 len -= 4;
459 while (len && isspace(*buf))
460 buf++, len--;
461 while (len && isspace(buf[len-1]))
462 len--;
463 buf[len] = 0;
464 memcpy(ref_buffer, buf, len + 1);
465 ref = ref_buffer;
466 if (flag)
467 *flag |= REF_ISSYMREF;
468 }
469 if (len < 40 || get_sha1_hex(buffer, sha1))
470 return NULL;
471 return ref;
472 }
473
474 int read_ref(const char *ref, unsigned char *sha1)
475 {
476 if (resolve_ref(ref, sha1, 1, NULL))
477 return 0;
478 return -1;
479 }
480
481 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
482 void *cb_data, struct ref_list *entry)
483 {
484 if (strncmp(base, entry->name, trim))
485 return 0;
486 if (is_null_sha1(entry->sha1))
487 return 0;
488 if (!has_sha1_file(entry->sha1)) {
489 error("%s does not point to a valid object!", entry->name);
490 return 0;
491 }
492 current_ref = entry;
493 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
494 }
495
496 int peel_ref(const char *ref, unsigned char *sha1)
497 {
498 int flag;
499 unsigned char base[20];
500 struct object *o;
501
502 if (current_ref && (current_ref->name == ref
503 || !strcmp(current_ref->name, ref))) {
504 if (current_ref->flag & REF_KNOWS_PEELED) {
505 hashcpy(sha1, current_ref->peeled);
506 return 0;
507 }
508 hashcpy(base, current_ref->sha1);
509 goto fallback;
510 }
511
512 if (!resolve_ref(ref, base, 1, &flag))
513 return -1;
514
515 if ((flag & REF_ISPACKED)) {
516 struct ref_list *list = get_packed_refs();
517
518 while (list) {
519 if (!strcmp(list->name, ref)) {
520 if (list->flag & REF_KNOWS_PEELED) {
521 hashcpy(sha1, list->peeled);
522 return 0;
523 }
524 /* older pack-refs did not leave peeled ones */
525 break;
526 }
527 list = list->next;
528 }
529 }
530
531 fallback:
532 o = parse_object(base);
533 if (o && o->type == OBJ_TAG) {
534 o = deref_tag(o, ref, 0);
535 if (o) {
536 hashcpy(sha1, o->sha1);
537 return 0;
538 }
539 }
540 return -1;
541 }
542
543 static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
544 void *cb_data)
545 {
546 int retval = 0;
547 struct ref_list *packed = get_packed_refs();
548 struct ref_list *loose = get_loose_refs();
549
550 while (packed && loose) {
551 struct ref_list *entry;
552 int cmp = strcmp(packed->name, loose->name);
553 if (!cmp) {
554 packed = packed->next;
555 continue;
556 }
557 if (cmp > 0) {
558 entry = loose;
559 loose = loose->next;
560 } else {
561 entry = packed;
562 packed = packed->next;
563 }
564 retval = do_one_ref(base, fn, trim, cb_data, entry);
565 if (retval)
566 goto end_each;
567 }
568
569 for (packed = packed ? packed : loose; packed; packed = packed->next) {
570 retval = do_one_ref(base, fn, trim, cb_data, packed);
571 if (retval)
572 goto end_each;
573 }
574
575 end_each:
576 current_ref = NULL;
577 return retval;
578 }
579
580 int head_ref(each_ref_fn fn, void *cb_data)
581 {
582 unsigned char sha1[20];
583 int flag;
584
585 if (resolve_ref("HEAD", sha1, 1, &flag))
586 return fn("HEAD", sha1, flag, cb_data);
587 return 0;
588 }
589
590 int for_each_ref(each_ref_fn fn, void *cb_data)
591 {
592 return do_for_each_ref("refs/", fn, 0, cb_data);
593 }
594
595 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
596 {
597 return do_for_each_ref("refs/tags/", fn, 10, cb_data);
598 }
599
600 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
601 {
602 return do_for_each_ref("refs/heads/", fn, 11, cb_data);
603 }
604
605 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
606 {
607 return do_for_each_ref("refs/remotes/", fn, 13, cb_data);
608 }
609
610 /*
611 * Make sure "ref" is something reasonable to have under ".git/refs/";
612 * We do not like it if:
613 *
614 * - any path component of it begins with ".", or
615 * - it has double dots "..", or
616 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
617 * - it ends with a "/".
618 */
619
620 static inline int bad_ref_char(int ch)
621 {
622 if (((unsigned) ch) <= ' ' ||
623 ch == '~' || ch == '^' || ch == ':')
624 return 1;
625 /* 2.13 Pattern Matching Notation */
626 if (ch == '?' || ch == '[') /* Unsupported */
627 return 1;
628 if (ch == '*') /* Supported at the end */
629 return 2;
630 return 0;
631 }
632
633 int check_ref_format(const char *ref)
634 {
635 int ch, level, bad_type;
636 const char *cp = ref;
637
638 level = 0;
639 while (1) {
640 while ((ch = *cp++) == '/')
641 ; /* tolerate duplicated slashes */
642 if (!ch)
643 /* should not end with slashes */
644 return CHECK_REF_FORMAT_ERROR;
645
646 /* we are at the beginning of the path component */
647 if (ch == '.')
648 return CHECK_REF_FORMAT_ERROR;
649 bad_type = bad_ref_char(ch);
650 if (bad_type) {
651 return (bad_type == 2 && !*cp)
652 ? CHECK_REF_FORMAT_WILDCARD
653 : CHECK_REF_FORMAT_ERROR;
654 }
655
656 /* scan the rest of the path component */
657 while ((ch = *cp++) != 0) {
658 bad_type = bad_ref_char(ch);
659 if (bad_type) {
660 return (bad_type == 2 && !*cp)
661 ? CHECK_REF_FORMAT_WILDCARD
662 : CHECK_REF_FORMAT_ERROR;
663 }
664 if (ch == '/')
665 break;
666 if (ch == '.' && *cp == '.')
667 return CHECK_REF_FORMAT_ERROR;
668 }
669 level++;
670 if (!ch) {
671 if (level < 2)
672 return CHECK_REF_FORMAT_ONELEVEL;
673 return CHECK_REF_FORMAT_OK;
674 }
675 }
676 }
677
678 const char *ref_rev_parse_rules[] = {
679 "%.*s",
680 "refs/%.*s",
681 "refs/tags/%.*s",
682 "refs/heads/%.*s",
683 "refs/remotes/%.*s",
684 "refs/remotes/%.*s/HEAD",
685 NULL
686 };
687
688 const char *ref_fetch_rules[] = {
689 "%.*s",
690 "refs/%.*s",
691 "refs/heads/%.*s",
692 NULL
693 };
694
695 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
696 {
697 const char **p;
698 const int abbrev_name_len = strlen(abbrev_name);
699
700 for (p = rules; *p; p++) {
701 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
702 return 1;
703 }
704 }
705
706 return 0;
707 }
708
709 static struct ref_lock *verify_lock(struct ref_lock *lock,
710 const unsigned char *old_sha1, int mustexist)
711 {
712 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
713 error("Can't verify ref %s", lock->ref_name);
714 unlock_ref(lock);
715 return NULL;
716 }
717 if (hashcmp(lock->old_sha1, old_sha1)) {
718 error("Ref %s is at %s but expected %s", lock->ref_name,
719 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
720 unlock_ref(lock);
721 return NULL;
722 }
723 return lock;
724 }
725
726 static int remove_empty_directories(const char *file)
727 {
728 /* we want to create a file but there is a directory there;
729 * if that is an empty directory (or a directory that contains
730 * only empty directories), remove them.
731 */
732 struct strbuf path;
733 int result;
734
735 strbuf_init(&path, 20);
736 strbuf_addstr(&path, file);
737
738 result = remove_dir_recursively(&path, 1);
739
740 strbuf_release(&path);
741
742 return result;
743 }
744
745 static int is_refname_available(const char *ref, const char *oldref,
746 struct ref_list *list, int quiet)
747 {
748 int namlen = strlen(ref); /* e.g. 'foo/bar' */
749 while (list) {
750 /* list->name could be 'foo' or 'foo/bar/baz' */
751 if (!oldref || strcmp(oldref, list->name)) {
752 int len = strlen(list->name);
753 int cmplen = (namlen < len) ? namlen : len;
754 const char *lead = (namlen < len) ? list->name : ref;
755 if (!strncmp(ref, list->name, cmplen) &&
756 lead[cmplen] == '/') {
757 if (!quiet)
758 error("'%s' exists; cannot create '%s'",
759 list->name, ref);
760 return 0;
761 }
762 }
763 list = list->next;
764 }
765 return 1;
766 }
767
768 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
769 {
770 char *ref_file;
771 const char *orig_ref = ref;
772 struct ref_lock *lock;
773 struct stat st;
774 int last_errno = 0;
775 int type;
776 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
777
778 lock = xcalloc(1, sizeof(struct ref_lock));
779 lock->lock_fd = -1;
780
781 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
782 if (!ref && errno == EISDIR) {
783 /* we are trying to lock foo but we used to
784 * have foo/bar which now does not exist;
785 * it is normal for the empty directory 'foo'
786 * to remain.
787 */
788 ref_file = git_path("%s", orig_ref);
789 if (remove_empty_directories(ref_file)) {
790 last_errno = errno;
791 error("there are still refs under '%s'", orig_ref);
792 goto error_return;
793 }
794 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
795 }
796 if (type_p)
797 *type_p = type;
798 if (!ref) {
799 last_errno = errno;
800 error("unable to resolve reference %s: %s",
801 orig_ref, strerror(errno));
802 goto error_return;
803 }
804 /* When the ref did not exist and we are creating it,
805 * make sure there is no existing ref that is packed
806 * whose name begins with our refname, nor a ref whose
807 * name is a proper prefix of our refname.
808 */
809 if (is_null_sha1(lock->old_sha1) &&
810 !is_refname_available(ref, NULL, get_packed_refs(), 0))
811 goto error_return;
812
813 lock->lk = xcalloc(1, sizeof(struct lock_file));
814
815 if (flags & REF_NODEREF)
816 ref = orig_ref;
817 lock->ref_name = xstrdup(ref);
818 lock->orig_ref_name = xstrdup(orig_ref);
819 ref_file = git_path("%s", ref);
820 if (lstat(ref_file, &st) && errno == ENOENT)
821 lock->force_write = 1;
822 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
823 lock->force_write = 1;
824
825 if (safe_create_leading_directories(ref_file)) {
826 last_errno = errno;
827 error("unable to create directory for %s", ref_file);
828 goto error_return;
829 }
830 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, 1);
831
832 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
833
834 error_return:
835 unlock_ref(lock);
836 errno = last_errno;
837 return NULL;
838 }
839
840 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
841 {
842 char refpath[PATH_MAX];
843 if (check_ref_format(ref))
844 return NULL;
845 strcpy(refpath, mkpath("refs/%s", ref));
846 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
847 }
848
849 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
850 {
851 switch (check_ref_format(ref)) {
852 default:
853 return NULL;
854 case 0:
855 case CHECK_REF_FORMAT_ONELEVEL:
856 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
857 }
858 }
859
860 static struct lock_file packlock;
861
862 static int repack_without_ref(const char *refname)
863 {
864 struct ref_list *list, *packed_ref_list;
865 int fd;
866 int found = 0;
867
868 packed_ref_list = get_packed_refs();
869 for (list = packed_ref_list; list; list = list->next) {
870 if (!strcmp(refname, list->name)) {
871 found = 1;
872 break;
873 }
874 }
875 if (!found)
876 return 0;
877 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
878 if (fd < 0)
879 return error("cannot delete '%s' from packed refs", refname);
880
881 for (list = packed_ref_list; list; list = list->next) {
882 char line[PATH_MAX + 100];
883 int len;
884
885 if (!strcmp(refname, list->name))
886 continue;
887 len = snprintf(line, sizeof(line), "%s %s\n",
888 sha1_to_hex(list->sha1), list->name);
889 /* this should not happen but just being defensive */
890 if (len > sizeof(line))
891 die("too long a refname '%s'", list->name);
892 write_or_die(fd, line, len);
893 }
894 return commit_lock_file(&packlock);
895 }
896
897 int delete_ref(const char *refname, const unsigned char *sha1)
898 {
899 struct ref_lock *lock;
900 int err, i, ret = 0, flag = 0;
901
902 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
903 if (!lock)
904 return 1;
905 if (!(flag & REF_ISPACKED)) {
906 /* loose */
907 i = strlen(lock->lk->filename) - 5; /* .lock */
908 lock->lk->filename[i] = 0;
909 err = unlink(lock->lk->filename);
910 if (err) {
911 ret = 1;
912 error("unlink(%s) failed: %s",
913 lock->lk->filename, strerror(errno));
914 }
915 lock->lk->filename[i] = '.';
916 }
917 /* removing the loose one could have resurrected an earlier
918 * packed one. Also, if it was not loose we need to repack
919 * without it.
920 */
921 ret |= repack_without_ref(refname);
922
923 err = unlink(git_path("logs/%s", lock->ref_name));
924 if (err && errno != ENOENT)
925 fprintf(stderr, "warning: unlink(%s) failed: %s",
926 git_path("logs/%s", lock->ref_name), strerror(errno));
927 invalidate_cached_refs();
928 unlock_ref(lock);
929 return ret;
930 }
931
932 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
933 {
934 static const char renamed_ref[] = "RENAMED-REF";
935 unsigned char sha1[20], orig_sha1[20];
936 int flag = 0, logmoved = 0;
937 struct ref_lock *lock;
938 struct stat loginfo;
939 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
940
941 if (S_ISLNK(loginfo.st_mode))
942 return error("reflog for %s is a symlink", oldref);
943
944 if (!resolve_ref(oldref, orig_sha1, 1, &flag))
945 return error("refname %s not found", oldref);
946
947 if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
948 return 1;
949
950 if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
951 return 1;
952
953 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
954 if (!lock)
955 return error("unable to lock %s", renamed_ref);
956 lock->force_write = 1;
957 if (write_ref_sha1(lock, orig_sha1, logmsg))
958 return error("unable to save current sha1 in %s", renamed_ref);
959
960 if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
961 return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
962 oldref, strerror(errno));
963
964 if (delete_ref(oldref, orig_sha1)) {
965 error("unable to delete old %s", oldref);
966 goto rollback;
967 }
968
969 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1)) {
970 if (errno==EISDIR) {
971 if (remove_empty_directories(git_path("%s", newref))) {
972 error("Directory not empty: %s", newref);
973 goto rollback;
974 }
975 } else {
976 error("unable to delete existing %s", newref);
977 goto rollback;
978 }
979 }
980
981 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
982 error("unable to create directory for %s", newref);
983 goto rollback;
984 }
985
986 retry:
987 if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
988 if (errno==EISDIR || errno==ENOTDIR) {
989 /*
990 * rename(a, b) when b is an existing
991 * directory ought to result in ISDIR, but
992 * Solaris 5.8 gives ENOTDIR. Sheesh.
993 */
994 if (remove_empty_directories(git_path("logs/%s", newref))) {
995 error("Directory not empty: logs/%s", newref);
996 goto rollback;
997 }
998 goto retry;
999 } else {
1000 error("unable to move logfile tmp-renamed-log to logs/%s: %s",
1001 newref, strerror(errno));
1002 goto rollback;
1003 }
1004 }
1005 logmoved = log;
1006
1007 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1008 if (!lock) {
1009 error("unable to lock %s for update", newref);
1010 goto rollback;
1011 }
1012
1013 lock->force_write = 1;
1014 hashcpy(lock->old_sha1, orig_sha1);
1015 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1016 error("unable to write current sha1 into %s", newref);
1017 goto rollback;
1018 }
1019
1020 return 0;
1021
1022 rollback:
1023 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1024 if (!lock) {
1025 error("unable to lock %s for rollback", oldref);
1026 goto rollbacklog;
1027 }
1028
1029 lock->force_write = 1;
1030 flag = log_all_ref_updates;
1031 log_all_ref_updates = 0;
1032 if (write_ref_sha1(lock, orig_sha1, NULL))
1033 error("unable to write current sha1 into %s", oldref);
1034 log_all_ref_updates = flag;
1035
1036 rollbacklog:
1037 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1038 error("unable to restore logfile %s from %s: %s",
1039 oldref, newref, strerror(errno));
1040 if (!logmoved && log &&
1041 rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
1042 error("unable to restore logfile %s from tmp-renamed-log: %s",
1043 oldref, strerror(errno));
1044
1045 return 1;
1046 }
1047
1048 int close_ref(struct ref_lock *lock)
1049 {
1050 if (close_lock_file(lock->lk))
1051 return -1;
1052 lock->lock_fd = -1;
1053 return 0;
1054 }
1055
1056 int commit_ref(struct ref_lock *lock)
1057 {
1058 if (commit_lock_file(lock->lk))
1059 return -1;
1060 lock->lock_fd = -1;
1061 return 0;
1062 }
1063
1064 void unlock_ref(struct ref_lock *lock)
1065 {
1066 /* Do not free lock->lk -- atexit() still looks at them */
1067 if (lock->lk)
1068 rollback_lock_file(lock->lk);
1069 free(lock->ref_name);
1070 free(lock->orig_ref_name);
1071 free(lock);
1072 }
1073
1074 /*
1075 * copy the reflog message msg to buf, which has been allocated sufficiently
1076 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1077 * because reflog file is one line per entry.
1078 */
1079 static int copy_msg(char *buf, const char *msg)
1080 {
1081 char *cp = buf;
1082 char c;
1083 int wasspace = 1;
1084
1085 *cp++ = '\t';
1086 while ((c = *msg++)) {
1087 if (wasspace && isspace(c))
1088 continue;
1089 wasspace = isspace(c);
1090 if (wasspace)
1091 c = ' ';
1092 *cp++ = c;
1093 }
1094 while (buf < cp && isspace(cp[-1]))
1095 cp--;
1096 *cp++ = '\n';
1097 return cp - buf;
1098 }
1099
1100 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1101 const unsigned char *new_sha1, const char *msg)
1102 {
1103 int logfd, written, oflags = O_APPEND | O_WRONLY;
1104 unsigned maxlen, len;
1105 int msglen;
1106 char *log_file, *logrec;
1107 const char *committer;
1108
1109 if (log_all_ref_updates < 0)
1110 log_all_ref_updates = !is_bare_repository();
1111
1112 log_file = git_path("logs/%s", ref_name);
1113
1114 if (log_all_ref_updates &&
1115 (!prefixcmp(ref_name, "refs/heads/") ||
1116 !prefixcmp(ref_name, "refs/remotes/") ||
1117 !strcmp(ref_name, "HEAD"))) {
1118 if (safe_create_leading_directories(log_file) < 0)
1119 return error("unable to create directory for %s",
1120 log_file);
1121 oflags |= O_CREAT;
1122 }
1123
1124 logfd = open(log_file, oflags, 0666);
1125 if (logfd < 0) {
1126 if (!(oflags & O_CREAT) && errno == ENOENT)
1127 return 0;
1128
1129 if ((oflags & O_CREAT) && errno == EISDIR) {
1130 if (remove_empty_directories(log_file)) {
1131 return error("There are still logs under '%s'",
1132 log_file);
1133 }
1134 logfd = open(log_file, oflags, 0666);
1135 }
1136
1137 if (logfd < 0)
1138 return error("Unable to append to %s: %s",
1139 log_file, strerror(errno));
1140 }
1141
1142 adjust_shared_perm(log_file);
1143
1144 msglen = msg ? strlen(msg) : 0;
1145 committer = git_committer_info(0);
1146 maxlen = strlen(committer) + msglen + 100;
1147 logrec = xmalloc(maxlen);
1148 len = sprintf(logrec, "%s %s %s\n",
1149 sha1_to_hex(old_sha1),
1150 sha1_to_hex(new_sha1),
1151 committer);
1152 if (msglen)
1153 len += copy_msg(logrec + len - 1, msg) - 1;
1154 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1155 free(logrec);
1156 if (close(logfd) != 0 || written != len)
1157 return error("Unable to append to %s", log_file);
1158 return 0;
1159 }
1160
1161 static int is_branch(const char *refname)
1162 {
1163 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1164 }
1165
1166 int write_ref_sha1(struct ref_lock *lock,
1167 const unsigned char *sha1, const char *logmsg)
1168 {
1169 static char term = '\n';
1170 struct object *o;
1171
1172 if (!lock)
1173 return -1;
1174 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1175 unlock_ref(lock);
1176 return 0;
1177 }
1178 o = parse_object(sha1);
1179 if (!o) {
1180 error("Trying to write ref %s with nonexistant object %s",
1181 lock->ref_name, sha1_to_hex(sha1));
1182 unlock_ref(lock);
1183 return -1;
1184 }
1185 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1186 error("Trying to write non-commit object %s to branch %s",
1187 sha1_to_hex(sha1), lock->ref_name);
1188 unlock_ref(lock);
1189 return -1;
1190 }
1191 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1192 write_in_full(lock->lock_fd, &term, 1) != 1
1193 || close_ref(lock) < 0) {
1194 error("Couldn't write %s", lock->lk->filename);
1195 unlock_ref(lock);
1196 return -1;
1197 }
1198 invalidate_cached_refs();
1199 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1200 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1201 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1202 unlock_ref(lock);
1203 return -1;
1204 }
1205 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1206 /*
1207 * Special hack: If a branch is updated directly and HEAD
1208 * points to it (may happen on the remote side of a push
1209 * for example) then logically the HEAD reflog should be
1210 * updated too.
1211 * A generic solution implies reverse symref information,
1212 * but finding all symrefs pointing to the given branch
1213 * would be rather costly for this rare event (the direct
1214 * update of a branch) to be worth it. So let's cheat and
1215 * check with HEAD only which should cover 99% of all usage
1216 * scenarios (even 100% of the default ones).
1217 */
1218 unsigned char head_sha1[20];
1219 int head_flag;
1220 const char *head_ref;
1221 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1222 if (head_ref && (head_flag & REF_ISSYMREF) &&
1223 !strcmp(head_ref, lock->ref_name))
1224 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1225 }
1226 if (commit_ref(lock)) {
1227 error("Couldn't set %s", lock->ref_name);
1228 unlock_ref(lock);
1229 return -1;
1230 }
1231 unlock_ref(lock);
1232 return 0;
1233 }
1234
1235 int create_symref(const char *ref_target, const char *refs_heads_master,
1236 const char *logmsg)
1237 {
1238 const char *lockpath;
1239 char ref[1000];
1240 int fd, len, written;
1241 char *git_HEAD = xstrdup(git_path("%s", ref_target));
1242 unsigned char old_sha1[20], new_sha1[20];
1243
1244 if (logmsg && read_ref(ref_target, old_sha1))
1245 hashclr(old_sha1);
1246
1247 if (safe_create_leading_directories(git_HEAD) < 0)
1248 return error("unable to create directory for %s", git_HEAD);
1249
1250 #ifndef NO_SYMLINK_HEAD
1251 if (prefer_symlink_refs) {
1252 unlink(git_HEAD);
1253 if (!symlink(refs_heads_master, git_HEAD))
1254 goto done;
1255 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1256 }
1257 #endif
1258
1259 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1260 if (sizeof(ref) <= len) {
1261 error("refname too long: %s", refs_heads_master);
1262 goto error_free_return;
1263 }
1264 lockpath = mkpath("%s.lock", git_HEAD);
1265 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1266 if (fd < 0) {
1267 error("Unable to open %s for writing", lockpath);
1268 goto error_free_return;
1269 }
1270 written = write_in_full(fd, ref, len);
1271 if (close(fd) != 0 || written != len) {
1272 error("Unable to write to %s", lockpath);
1273 goto error_unlink_return;
1274 }
1275 if (rename(lockpath, git_HEAD) < 0) {
1276 error("Unable to create %s", git_HEAD);
1277 goto error_unlink_return;
1278 }
1279 if (adjust_shared_perm(git_HEAD)) {
1280 error("Unable to fix permissions on %s", lockpath);
1281 error_unlink_return:
1282 unlink(lockpath);
1283 error_free_return:
1284 free(git_HEAD);
1285 return -1;
1286 }
1287
1288 #ifndef NO_SYMLINK_HEAD
1289 done:
1290 #endif
1291 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1292 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1293
1294 free(git_HEAD);
1295 return 0;
1296 }
1297
1298 static char *ref_msg(const char *line, const char *endp)
1299 {
1300 const char *ep;
1301 line += 82;
1302 ep = memchr(line, '\n', endp - line);
1303 if (!ep)
1304 ep = endp;
1305 return xmemdupz(line, ep - line);
1306 }
1307
1308 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)
1309 {
1310 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1311 char *tz_c;
1312 int logfd, tz, reccnt = 0;
1313 struct stat st;
1314 unsigned long date;
1315 unsigned char logged_sha1[20];
1316 void *log_mapped;
1317 size_t mapsz;
1318
1319 logfile = git_path("logs/%s", ref);
1320 logfd = open(logfile, O_RDONLY, 0);
1321 if (logfd < 0)
1322 die("Unable to read log %s: %s", logfile, strerror(errno));
1323 fstat(logfd, &st);
1324 if (!st.st_size)
1325 die("Log %s is empty.", logfile);
1326 mapsz = xsize_t(st.st_size);
1327 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1328 logdata = log_mapped;
1329 close(logfd);
1330
1331 lastrec = NULL;
1332 rec = logend = logdata + st.st_size;
1333 while (logdata < rec) {
1334 reccnt++;
1335 if (logdata < rec && *(rec-1) == '\n')
1336 rec--;
1337 lastgt = NULL;
1338 while (logdata < rec && *(rec-1) != '\n') {
1339 rec--;
1340 if (*rec == '>')
1341 lastgt = rec;
1342 }
1343 if (!lastgt)
1344 die("Log %s is corrupt.", logfile);
1345 date = strtoul(lastgt + 1, &tz_c, 10);
1346 if (date <= at_time || cnt == 0) {
1347 tz = strtoul(tz_c, NULL, 10);
1348 if (msg)
1349 *msg = ref_msg(rec, logend);
1350 if (cutoff_time)
1351 *cutoff_time = date;
1352 if (cutoff_tz)
1353 *cutoff_tz = tz;
1354 if (cutoff_cnt)
1355 *cutoff_cnt = reccnt - 1;
1356 if (lastrec) {
1357 if (get_sha1_hex(lastrec, logged_sha1))
1358 die("Log %s is corrupt.", logfile);
1359 if (get_sha1_hex(rec + 41, sha1))
1360 die("Log %s is corrupt.", logfile);
1361 if (hashcmp(logged_sha1, sha1)) {
1362 fprintf(stderr,
1363 "warning: Log %s has gap after %s.\n",
1364 logfile, show_date(date, tz, DATE_RFC2822));
1365 }
1366 }
1367 else if (date == at_time) {
1368 if (get_sha1_hex(rec + 41, sha1))
1369 die("Log %s is corrupt.", logfile);
1370 }
1371 else {
1372 if (get_sha1_hex(rec + 41, logged_sha1))
1373 die("Log %s is corrupt.", logfile);
1374 if (hashcmp(logged_sha1, sha1)) {
1375 fprintf(stderr,
1376 "warning: Log %s unexpectedly ended on %s.\n",
1377 logfile, show_date(date, tz, DATE_RFC2822));
1378 }
1379 }
1380 munmap(log_mapped, mapsz);
1381 return 0;
1382 }
1383 lastrec = rec;
1384 if (cnt > 0)
1385 cnt--;
1386 }
1387
1388 rec = logdata;
1389 while (rec < logend && *rec != '>' && *rec != '\n')
1390 rec++;
1391 if (rec == logend || *rec == '\n')
1392 die("Log %s is corrupt.", logfile);
1393 date = strtoul(rec + 1, &tz_c, 10);
1394 tz = strtoul(tz_c, NULL, 10);
1395 if (get_sha1_hex(logdata, sha1))
1396 die("Log %s is corrupt.", logfile);
1397 if (msg)
1398 *msg = ref_msg(logdata, logend);
1399 munmap(log_mapped, mapsz);
1400
1401 if (cutoff_time)
1402 *cutoff_time = date;
1403 if (cutoff_tz)
1404 *cutoff_tz = tz;
1405 if (cutoff_cnt)
1406 *cutoff_cnt = reccnt;
1407 return 1;
1408 }
1409
1410 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1411 {
1412 const char *logfile;
1413 FILE *logfp;
1414 char buf[1024];
1415 int ret = 0;
1416
1417 logfile = git_path("logs/%s", ref);
1418 logfp = fopen(logfile, "r");
1419 if (!logfp)
1420 return -1;
1421 while (fgets(buf, sizeof(buf), logfp)) {
1422 unsigned char osha1[20], nsha1[20];
1423 char *email_end, *message;
1424 unsigned long timestamp;
1425 int len, tz;
1426
1427 /* old SP new SP name <email> SP time TAB msg LF */
1428 len = strlen(buf);
1429 if (len < 83 || buf[len-1] != '\n' ||
1430 get_sha1_hex(buf, osha1) || buf[40] != ' ' ||
1431 get_sha1_hex(buf + 41, nsha1) || buf[81] != ' ' ||
1432 !(email_end = strchr(buf + 82, '>')) ||
1433 email_end[1] != ' ' ||
1434 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1435 !message || message[0] != ' ' ||
1436 (message[1] != '+' && message[1] != '-') ||
1437 !isdigit(message[2]) || !isdigit(message[3]) ||
1438 !isdigit(message[4]) || !isdigit(message[5]))
1439 continue; /* corrupt? */
1440 email_end[1] = '\0';
1441 tz = strtol(message + 1, NULL, 10);
1442 if (message[6] != '\t')
1443 message += 6;
1444 else
1445 message += 7;
1446 ret = fn(osha1, nsha1, buf+82, timestamp, tz, message, cb_data);
1447 if (ret)
1448 break;
1449 }
1450 fclose(logfp);
1451 return ret;
1452 }
1453
1454 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1455 {
1456 DIR *dir = opendir(git_path("logs/%s", base));
1457 int retval = 0;
1458
1459 if (dir) {
1460 struct dirent *de;
1461 int baselen = strlen(base);
1462 char *log = xmalloc(baselen + 257);
1463
1464 memcpy(log, base, baselen);
1465 if (baselen && base[baselen-1] != '/')
1466 log[baselen++] = '/';
1467
1468 while ((de = readdir(dir)) != NULL) {
1469 struct stat st;
1470 int namelen;
1471
1472 if (de->d_name[0] == '.')
1473 continue;
1474 namelen = strlen(de->d_name);
1475 if (namelen > 255)
1476 continue;
1477 if (has_extension(de->d_name, ".lock"))
1478 continue;
1479 memcpy(log + baselen, de->d_name, namelen+1);
1480 if (stat(git_path("logs/%s", log), &st) < 0)
1481 continue;
1482 if (S_ISDIR(st.st_mode)) {
1483 retval = do_for_each_reflog(log, fn, cb_data);
1484 } else {
1485 unsigned char sha1[20];
1486 if (!resolve_ref(log, sha1, 0, NULL))
1487 retval = error("bad ref for %s", log);
1488 else
1489 retval = fn(log, sha1, 0, cb_data);
1490 }
1491 if (retval)
1492 break;
1493 }
1494 free(log);
1495 closedir(dir);
1496 }
1497 else if (*base)
1498 return errno;
1499 return retval;
1500 }
1501
1502 int for_each_reflog(each_ref_fn fn, void *cb_data)
1503 {
1504 return do_for_each_reflog("", fn, cb_data);
1505 }
1506
1507 int update_ref(const char *action, const char *refname,
1508 const unsigned char *sha1, const unsigned char *oldval,
1509 int flags, enum action_on_err onerr)
1510 {
1511 static struct ref_lock *lock;
1512 lock = lock_any_ref_for_update(refname, oldval, flags);
1513 if (!lock) {
1514 const char *str = "Cannot lock the ref '%s'.";
1515 switch (onerr) {
1516 case MSG_ON_ERR: error(str, refname); break;
1517 case DIE_ON_ERR: die(str, refname); break;
1518 case QUIET_ON_ERR: break;
1519 }
1520 return 1;
1521 }
1522 if (write_ref_sha1(lock, sha1, action) < 0) {
1523 const char *str = "Cannot update the ref '%s'.";
1524 switch (onerr) {
1525 case MSG_ON_ERR: error(str, refname); break;
1526 case DIE_ON_ERR: die(str, refname); break;
1527 case QUIET_ON_ERR: break;
1528 }
1529 return 1;
1530 }
1531 return 0;
1532 }
1533
1534 struct ref *find_ref_by_name(struct ref *list, const char *name)
1535 {
1536 for ( ; list; list = list->next)
1537 if (!strcmp(list->name, name))
1538 return list;
1539 return NULL;
1540 }