rev-parse --branches/--tags/--remotes=pattern
[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 struct ref_list *extra_refs;
163
164 static void free_ref_list(struct ref_list *list)
165 {
166 struct ref_list *next;
167 for ( ; list; list = next) {
168 next = list->next;
169 free(list);
170 }
171 }
172
173 static void invalidate_cached_refs(void)
174 {
175 struct cached_refs *ca = &cached_refs;
176
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;
183 }
184
185 static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
186 {
187 struct ref_list *list = NULL;
188 struct ref_list *last = NULL;
189 char refline[PATH_MAX];
190 int flag = REF_ISPACKED;
191
192 while (fgets(refline, sizeof(refline), f)) {
193 unsigned char sha1[20];
194 const char *name;
195 static const char header[] = "# pack-refs with:";
196
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;
203 }
204
205 name = parse_ref_line(refline, sha1);
206 if (name) {
207 list = add_ref(name, sha1, flag, list, &last);
208 continue;
209 }
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);
216 }
217 cached_refs->packed = sort_ref_list(list);
218 }
219
220 void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
221 {
222 extra_refs = add_ref(name, sha1, flag, extra_refs, NULL);
223 }
224
225 void clear_extra_refs(void)
226 {
227 free_ref_list(extra_refs);
228 extra_refs = NULL;
229 }
230
231 static struct ref_list *get_packed_refs(void)
232 {
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);
239 }
240 cached_refs.did_packed = 1;
241 }
242 return cached_refs.packed;
243 }
244
245 static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
246 {
247 DIR *dir = opendir(git_path("%s", base));
248
249 if (dir) {
250 struct dirent *de;
251 int baselen = strlen(base);
252 char *ref = xmalloc(baselen + 257);
253
254 memcpy(ref, base, baselen);
255 if (baselen && base[baselen-1] != '/')
256 ref[baselen++] = '/';
257
258 while ((de = readdir(dir)) != NULL) {
259 unsigned char sha1[20];
260 struct stat st;
261 int flag;
262 int namelen;
263
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;
277 }
278 if (!resolve_ref(ref, sha1, 1, &flag))
279 hashclr(sha1);
280 list = add_ref(ref, sha1, flag, list, NULL);
281 }
282 free(ref);
283 closedir(dir);
284 }
285 return sort_ref_list(list);
286 }
287
288 struct warn_if_dangling_data {
289 FILE *fp;
290 const char *refname;
291 const char *msg_fmt;
292 };
293
294 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
295 int flags, void *cb_data)
296 {
297 struct warn_if_dangling_data *d = cb_data;
298 const char *resolves_to;
299 unsigned char junk[20];
300
301 if (!(flags & REF_ISSYMREF))
302 return 0;
303
304 resolves_to = resolve_ref(refname, junk, 0, NULL);
305 if (!resolves_to || strcmp(resolves_to, d->refname))
306 return 0;
307
308 fprintf(d->fp, d->msg_fmt, refname);
309 return 0;
310 }
311
312 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
313 {
314 struct warn_if_dangling_data data = { fp, refname, msg_fmt };
315 for_each_rawref(warn_if_dangling_symref, &data);
316 }
317
318 static struct ref_list *get_loose_refs(void)
319 {
320 if (!cached_refs.did_loose) {
321 cached_refs.loose = get_ref_dir("refs", NULL);
322 cached_refs.did_loose = 1;
323 }
324 return cached_refs.loose;
325 }
326
327 /* We allow "recursive" symbolic refs. Only within reason, though */
328 #define MAXDEPTH 5
329 #define MAXREFLEN (1024)
330
331 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
332 {
333 FILE *f;
334 struct cached_refs refs;
335 struct ref_list *ref;
336 int retval;
337
338 strcpy(name + pathlen, "packed-refs");
339 f = fopen(name, "r");
340 if (!f)
341 return -1;
342 read_packed_refs(f, &refs);
343 fclose(f);
344 ref = refs.packed;
345 retval = -1;
346 while (ref) {
347 if (!strcmp(ref->name, refname)) {
348 retval = 0;
349 memcpy(result, ref->sha1, 20);
350 break;
351 }
352 ref = ref->next;
353 }
354 free_ref_list(refs.packed);
355 return retval;
356 }
357
358 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
359 {
360 int fd, len = strlen(refname);
361 char buffer[128], *p;
362
363 if (recursion > MAXDEPTH || len > MAXREFLEN)
364 return -1;
365 memcpy(name + pathlen, refname, len+1);
366 fd = open(name, O_RDONLY);
367 if (fd < 0)
368 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
369
370 len = read(fd, buffer, sizeof(buffer)-1);
371 close(fd);
372 if (len < 0)
373 return -1;
374 while (len && isspace(buffer[len-1]))
375 len--;
376 buffer[len] = 0;
377
378 /* Was it a detached head or an old-fashioned symlink? */
379 if (!get_sha1_hex(buffer, result))
380 return 0;
381
382 /* Symref? */
383 if (strncmp(buffer, "ref:", 4))
384 return -1;
385 p = buffer + 4;
386 while (isspace(*p))
387 p++;
388
389 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
390 }
391
392 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
393 {
394 int len = strlen(path), retval;
395 char *gitdir;
396 const char *tmp;
397
398 while (len && path[len-1] == '/')
399 len--;
400 if (!len)
401 return -1;
402 gitdir = xmalloc(len + MAXREFLEN + 8);
403 memcpy(gitdir, path, len);
404 memcpy(gitdir + len, "/.git", 6);
405 len += 5;
406
407 tmp = read_gitfile_gently(gitdir);
408 if (tmp) {
409 free(gitdir);
410 len = strlen(tmp);
411 gitdir = xmalloc(len + MAXREFLEN + 3);
412 memcpy(gitdir, tmp, len);
413 }
414 gitdir[len] = '/';
415 gitdir[++len] = '\0';
416 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
417 free(gitdir);
418 return retval;
419 }
420
421 /*
422 * If the "reading" argument is set, this function finds out what _object_
423 * the ref points at by "reading" the ref. The ref, if it is not symbolic,
424 * has to exist, and if it is symbolic, it has to point at an existing ref,
425 * because the "read" goes through the symref to the ref it points at.
426 *
427 * The access that is not "reading" may often be "writing", but does not
428 * have to; it can be merely checking _where it leads to_. If it is a
429 * prelude to "writing" to the ref, a write to a symref that points at
430 * yet-to-be-born ref will create the real ref pointed by the symref.
431 * reading=0 allows the caller to check where such a symref leads to.
432 */
433 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
434 {
435 int depth = MAXDEPTH;
436 ssize_t len;
437 char buffer[256];
438 static char ref_buffer[256];
439
440 if (flag)
441 *flag = 0;
442
443 for (;;) {
444 char path[PATH_MAX];
445 struct stat st;
446 char *buf;
447 int fd;
448
449 if (--depth < 0)
450 return NULL;
451
452 git_snpath(path, sizeof(path), "%s", ref);
453 /* Special case: non-existing file. */
454 if (lstat(path, &st) < 0) {
455 struct ref_list *list = get_packed_refs();
456 while (list) {
457 if (!strcmp(ref, list->name)) {
458 hashcpy(sha1, list->sha1);
459 if (flag)
460 *flag |= REF_ISPACKED;
461 return ref;
462 }
463 list = list->next;
464 }
465 if (reading || errno != ENOENT)
466 return NULL;
467 hashclr(sha1);
468 return ref;
469 }
470
471 /* Follow "normalized" - ie "refs/.." symlinks by hand */
472 if (S_ISLNK(st.st_mode)) {
473 len = readlink(path, buffer, sizeof(buffer)-1);
474 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
475 buffer[len] = 0;
476 strcpy(ref_buffer, buffer);
477 ref = ref_buffer;
478 if (flag)
479 *flag |= REF_ISSYMREF;
480 continue;
481 }
482 }
483
484 /* Is it a directory? */
485 if (S_ISDIR(st.st_mode)) {
486 errno = EISDIR;
487 return NULL;
488 }
489
490 /*
491 * Anything else, just open it and try to use it as
492 * a ref
493 */
494 fd = open(path, O_RDONLY);
495 if (fd < 0)
496 return NULL;
497 len = read_in_full(fd, buffer, sizeof(buffer)-1);
498 close(fd);
499
500 /*
501 * Is it a symbolic ref?
502 */
503 if (len < 4 || memcmp("ref:", buffer, 4))
504 break;
505 buf = buffer + 4;
506 len -= 4;
507 while (len && isspace(*buf))
508 buf++, len--;
509 while (len && isspace(buf[len-1]))
510 len--;
511 buf[len] = 0;
512 memcpy(ref_buffer, buf, len + 1);
513 ref = ref_buffer;
514 if (flag)
515 *flag |= REF_ISSYMREF;
516 }
517 if (len < 40 || get_sha1_hex(buffer, sha1))
518 return NULL;
519 return ref;
520 }
521
522 /* The argument to filter_refs */
523 struct ref_filter {
524 const char *pattern;
525 each_ref_fn *fn;
526 void *cb_data;
527 };
528
529 int read_ref(const char *ref, unsigned char *sha1)
530 {
531 if (resolve_ref(ref, sha1, 1, NULL))
532 return 0;
533 return -1;
534 }
535
536 #define DO_FOR_EACH_INCLUDE_BROKEN 01
537 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
538 int flags, void *cb_data, struct ref_list *entry)
539 {
540 if (strncmp(base, entry->name, trim))
541 return 0;
542 /* Is this a "negative ref" that represents a deleted ref? */
543 if (is_null_sha1(entry->sha1))
544 return 0;
545 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
546 if (!has_sha1_file(entry->sha1)) {
547 error("%s does not point to a valid object!", entry->name);
548 return 0;
549 }
550 }
551 current_ref = entry;
552 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
553 }
554
555 static int filter_refs(const char *ref, const unsigned char *sha, int flags,
556 void *data)
557 {
558 struct ref_filter *filter = (struct ref_filter *)data;
559 if (fnmatch(filter->pattern, ref, 0))
560 return 0;
561 return filter->fn(ref, sha, flags, filter->cb_data);
562 }
563
564 int peel_ref(const char *ref, unsigned char *sha1)
565 {
566 int flag;
567 unsigned char base[20];
568 struct object *o;
569
570 if (current_ref && (current_ref->name == ref
571 || !strcmp(current_ref->name, ref))) {
572 if (current_ref->flag & REF_KNOWS_PEELED) {
573 hashcpy(sha1, current_ref->peeled);
574 return 0;
575 }
576 hashcpy(base, current_ref->sha1);
577 goto fallback;
578 }
579
580 if (!resolve_ref(ref, base, 1, &flag))
581 return -1;
582
583 if ((flag & REF_ISPACKED)) {
584 struct ref_list *list = get_packed_refs();
585
586 while (list) {
587 if (!strcmp(list->name, ref)) {
588 if (list->flag & REF_KNOWS_PEELED) {
589 hashcpy(sha1, list->peeled);
590 return 0;
591 }
592 /* older pack-refs did not leave peeled ones */
593 break;
594 }
595 list = list->next;
596 }
597 }
598
599 fallback:
600 o = parse_object(base);
601 if (o && o->type == OBJ_TAG) {
602 o = deref_tag(o, ref, 0);
603 if (o) {
604 hashcpy(sha1, o->sha1);
605 return 0;
606 }
607 }
608 return -1;
609 }
610
611 static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
612 int flags, void *cb_data)
613 {
614 int retval = 0;
615 struct ref_list *packed = get_packed_refs();
616 struct ref_list *loose = get_loose_refs();
617
618 struct ref_list *extra;
619
620 for (extra = extra_refs; extra; extra = extra->next)
621 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
622
623 while (packed && loose) {
624 struct ref_list *entry;
625 int cmp = strcmp(packed->name, loose->name);
626 if (!cmp) {
627 packed = packed->next;
628 continue;
629 }
630 if (cmp > 0) {
631 entry = loose;
632 loose = loose->next;
633 } else {
634 entry = packed;
635 packed = packed->next;
636 }
637 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
638 if (retval)
639 goto end_each;
640 }
641
642 for (packed = packed ? packed : loose; packed; packed = packed->next) {
643 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
644 if (retval)
645 goto end_each;
646 }
647
648 end_each:
649 current_ref = NULL;
650 return retval;
651 }
652
653 int head_ref(each_ref_fn fn, void *cb_data)
654 {
655 unsigned char sha1[20];
656 int flag;
657
658 if (resolve_ref("HEAD", sha1, 1, &flag))
659 return fn("HEAD", sha1, flag, cb_data);
660 return 0;
661 }
662
663 int for_each_ref(each_ref_fn fn, void *cb_data)
664 {
665 return do_for_each_ref("refs/", fn, 0, 0, cb_data);
666 }
667
668 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
669 {
670 return do_for_each_ref(prefix, fn, strlen(prefix), 0, cb_data);
671 }
672
673 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
674 {
675 return for_each_ref_in("refs/tags/", fn, cb_data);
676 }
677
678 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
679 {
680 return for_each_ref_in("refs/heads/", fn, cb_data);
681 }
682
683 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
684 {
685 return for_each_ref_in("refs/remotes/", fn, cb_data);
686 }
687
688 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
689 {
690 return do_for_each_ref("refs/replace/", fn, 13, 0, cb_data);
691 }
692
693 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
694 const char *prefix, void *cb_data)
695 {
696 struct strbuf real_pattern = STRBUF_INIT;
697 struct ref_filter filter;
698 const char *has_glob_specials;
699 int ret;
700
701 if (!prefix && prefixcmp(pattern, "refs/"))
702 strbuf_addstr(&real_pattern, "refs/");
703 else if (prefix)
704 strbuf_addstr(&real_pattern, prefix);
705 strbuf_addstr(&real_pattern, pattern);
706
707 has_glob_specials = strpbrk(pattern, "?*[");
708 if (!has_glob_specials) {
709 /* Append impiled '/' '*' if not present. */
710 if (real_pattern.buf[real_pattern.len - 1] != '/')
711 strbuf_addch(&real_pattern, '/');
712 /* No need to check for '*', there is none. */
713 strbuf_addch(&real_pattern, '*');
714 }
715
716 filter.pattern = real_pattern.buf;
717 filter.fn = fn;
718 filter.cb_data = cb_data;
719 ret = for_each_ref(filter_refs, &filter);
720
721 strbuf_release(&real_pattern);
722 return ret;
723 }
724
725 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
726 {
727 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
728 }
729
730 int for_each_rawref(each_ref_fn fn, void *cb_data)
731 {
732 return do_for_each_ref("refs/", fn, 0,
733 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
734 }
735
736 /*
737 * Make sure "ref" is something reasonable to have under ".git/refs/";
738 * We do not like it if:
739 *
740 * - any path component of it begins with ".", or
741 * - it has double dots "..", or
742 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
743 * - it ends with a "/".
744 * - it ends with ".lock"
745 * - it contains a "\" (backslash)
746 */
747
748 static inline int bad_ref_char(int ch)
749 {
750 if (((unsigned) ch) <= ' ' ||
751 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
752 return 1;
753 /* 2.13 Pattern Matching Notation */
754 if (ch == '?' || ch == '[') /* Unsupported */
755 return 1;
756 if (ch == '*') /* Supported at the end */
757 return 2;
758 return 0;
759 }
760
761 int check_ref_format(const char *ref)
762 {
763 int ch, level, bad_type, last;
764 int ret = CHECK_REF_FORMAT_OK;
765 const char *cp = ref;
766
767 level = 0;
768 while (1) {
769 while ((ch = *cp++) == '/')
770 ; /* tolerate duplicated slashes */
771 if (!ch)
772 /* should not end with slashes */
773 return CHECK_REF_FORMAT_ERROR;
774
775 /* we are at the beginning of the path component */
776 if (ch == '.')
777 return CHECK_REF_FORMAT_ERROR;
778 bad_type = bad_ref_char(ch);
779 if (bad_type) {
780 if (bad_type == 2 && (!*cp || *cp == '/') &&
781 ret == CHECK_REF_FORMAT_OK)
782 ret = CHECK_REF_FORMAT_WILDCARD;
783 else
784 return CHECK_REF_FORMAT_ERROR;
785 }
786
787 last = ch;
788 /* scan the rest of the path component */
789 while ((ch = *cp++) != 0) {
790 bad_type = bad_ref_char(ch);
791 if (bad_type)
792 return CHECK_REF_FORMAT_ERROR;
793 if (ch == '/')
794 break;
795 if (last == '.' && ch == '.')
796 return CHECK_REF_FORMAT_ERROR;
797 if (last == '@' && ch == '{')
798 return CHECK_REF_FORMAT_ERROR;
799 last = ch;
800 }
801 level++;
802 if (!ch) {
803 if (ref <= cp - 2 && cp[-2] == '.')
804 return CHECK_REF_FORMAT_ERROR;
805 if (level < 2)
806 return CHECK_REF_FORMAT_ONELEVEL;
807 if (has_extension(ref, ".lock"))
808 return CHECK_REF_FORMAT_ERROR;
809 return ret;
810 }
811 }
812 }
813
814 const char *prettify_refname(const char *name)
815 {
816 return name + (
817 !prefixcmp(name, "refs/heads/") ? 11 :
818 !prefixcmp(name, "refs/tags/") ? 10 :
819 !prefixcmp(name, "refs/remotes/") ? 13 :
820 0);
821 }
822
823 const char *ref_rev_parse_rules[] = {
824 "%.*s",
825 "refs/%.*s",
826 "refs/tags/%.*s",
827 "refs/heads/%.*s",
828 "refs/remotes/%.*s",
829 "refs/remotes/%.*s/HEAD",
830 NULL
831 };
832
833 const char *ref_fetch_rules[] = {
834 "%.*s",
835 "refs/%.*s",
836 "refs/heads/%.*s",
837 NULL
838 };
839
840 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
841 {
842 const char **p;
843 const int abbrev_name_len = strlen(abbrev_name);
844
845 for (p = rules; *p; p++) {
846 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
847 return 1;
848 }
849 }
850
851 return 0;
852 }
853
854 static struct ref_lock *verify_lock(struct ref_lock *lock,
855 const unsigned char *old_sha1, int mustexist)
856 {
857 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
858 error("Can't verify ref %s", lock->ref_name);
859 unlock_ref(lock);
860 return NULL;
861 }
862 if (hashcmp(lock->old_sha1, old_sha1)) {
863 error("Ref %s is at %s but expected %s", lock->ref_name,
864 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
865 unlock_ref(lock);
866 return NULL;
867 }
868 return lock;
869 }
870
871 static int remove_empty_directories(const char *file)
872 {
873 /* we want to create a file but there is a directory there;
874 * if that is an empty directory (or a directory that contains
875 * only empty directories), remove them.
876 */
877 struct strbuf path;
878 int result;
879
880 strbuf_init(&path, 20);
881 strbuf_addstr(&path, file);
882
883 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
884
885 strbuf_release(&path);
886
887 return result;
888 }
889
890 static int is_refname_available(const char *ref, const char *oldref,
891 struct ref_list *list, int quiet)
892 {
893 int namlen = strlen(ref); /* e.g. 'foo/bar' */
894 while (list) {
895 /* list->name could be 'foo' or 'foo/bar/baz' */
896 if (!oldref || strcmp(oldref, list->name)) {
897 int len = strlen(list->name);
898 int cmplen = (namlen < len) ? namlen : len;
899 const char *lead = (namlen < len) ? list->name : ref;
900 if (!strncmp(ref, list->name, cmplen) &&
901 lead[cmplen] == '/') {
902 if (!quiet)
903 error("'%s' exists; cannot create '%s'",
904 list->name, ref);
905 return 0;
906 }
907 }
908 list = list->next;
909 }
910 return 1;
911 }
912
913 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
914 {
915 char *ref_file;
916 const char *orig_ref = ref;
917 struct ref_lock *lock;
918 int last_errno = 0;
919 int type, lflags;
920 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
921 int missing = 0;
922
923 lock = xcalloc(1, sizeof(struct ref_lock));
924 lock->lock_fd = -1;
925
926 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
927 if (!ref && errno == EISDIR) {
928 /* we are trying to lock foo but we used to
929 * have foo/bar which now does not exist;
930 * it is normal for the empty directory 'foo'
931 * to remain.
932 */
933 ref_file = git_path("%s", orig_ref);
934 if (remove_empty_directories(ref_file)) {
935 last_errno = errno;
936 error("there are still refs under '%s'", orig_ref);
937 goto error_return;
938 }
939 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
940 }
941 if (type_p)
942 *type_p = type;
943 if (!ref) {
944 last_errno = errno;
945 error("unable to resolve reference %s: %s",
946 orig_ref, strerror(errno));
947 goto error_return;
948 }
949 missing = is_null_sha1(lock->old_sha1);
950 /* When the ref did not exist and we are creating it,
951 * make sure there is no existing ref that is packed
952 * whose name begins with our refname, nor a ref whose
953 * name is a proper prefix of our refname.
954 */
955 if (missing &&
956 !is_refname_available(ref, NULL, get_packed_refs(), 0)) {
957 last_errno = ENOTDIR;
958 goto error_return;
959 }
960
961 lock->lk = xcalloc(1, sizeof(struct lock_file));
962
963 lflags = LOCK_DIE_ON_ERROR;
964 if (flags & REF_NODEREF) {
965 ref = orig_ref;
966 lflags |= LOCK_NODEREF;
967 }
968 lock->ref_name = xstrdup(ref);
969 lock->orig_ref_name = xstrdup(orig_ref);
970 ref_file = git_path("%s", ref);
971 if (missing)
972 lock->force_write = 1;
973 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
974 lock->force_write = 1;
975
976 if (safe_create_leading_directories(ref_file)) {
977 last_errno = errno;
978 error("unable to create directory for %s", ref_file);
979 goto error_return;
980 }
981
982 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
983 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
984
985 error_return:
986 unlock_ref(lock);
987 errno = last_errno;
988 return NULL;
989 }
990
991 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
992 {
993 char refpath[PATH_MAX];
994 if (check_ref_format(ref))
995 return NULL;
996 strcpy(refpath, mkpath("refs/%s", ref));
997 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
998 }
999
1000 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
1001 {
1002 switch (check_ref_format(ref)) {
1003 default:
1004 return NULL;
1005 case 0:
1006 case CHECK_REF_FORMAT_ONELEVEL:
1007 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1008 }
1009 }
1010
1011 static struct lock_file packlock;
1012
1013 static int repack_without_ref(const char *refname)
1014 {
1015 struct ref_list *list, *packed_ref_list;
1016 int fd;
1017 int found = 0;
1018
1019 packed_ref_list = get_packed_refs();
1020 for (list = packed_ref_list; list; list = list->next) {
1021 if (!strcmp(refname, list->name)) {
1022 found = 1;
1023 break;
1024 }
1025 }
1026 if (!found)
1027 return 0;
1028 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1029 if (fd < 0) {
1030 unable_to_lock_error(git_path("packed-refs"), errno);
1031 return error("cannot delete '%s' from packed refs", refname);
1032 }
1033
1034 for (list = packed_ref_list; list; list = list->next) {
1035 char line[PATH_MAX + 100];
1036 int len;
1037
1038 if (!strcmp(refname, list->name))
1039 continue;
1040 len = snprintf(line, sizeof(line), "%s %s\n",
1041 sha1_to_hex(list->sha1), list->name);
1042 /* this should not happen but just being defensive */
1043 if (len > sizeof(line))
1044 die("too long a refname '%s'", list->name);
1045 write_or_die(fd, line, len);
1046 }
1047 return commit_lock_file(&packlock);
1048 }
1049
1050 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1051 {
1052 struct ref_lock *lock;
1053 int err, i = 0, ret = 0, flag = 0;
1054
1055 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1056 if (!lock)
1057 return 1;
1058 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1059 /* loose */
1060 const char *path;
1061
1062 if (!(delopt & REF_NODEREF)) {
1063 i = strlen(lock->lk->filename) - 5; /* .lock */
1064 lock->lk->filename[i] = 0;
1065 path = lock->lk->filename;
1066 } else {
1067 path = git_path("%s", refname);
1068 }
1069 err = unlink_or_warn(path);
1070 if (err && errno != ENOENT)
1071 ret = 1;
1072
1073 if (!(delopt & REF_NODEREF))
1074 lock->lk->filename[i] = '.';
1075 }
1076 /* removing the loose one could have resurrected an earlier
1077 * packed one. Also, if it was not loose we need to repack
1078 * without it.
1079 */
1080 ret |= repack_without_ref(refname);
1081
1082 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1083 invalidate_cached_refs();
1084 unlock_ref(lock);
1085 return ret;
1086 }
1087
1088 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1089 {
1090 static const char renamed_ref[] = "RENAMED-REF";
1091 unsigned char sha1[20], orig_sha1[20];
1092 int flag = 0, logmoved = 0;
1093 struct ref_lock *lock;
1094 struct stat loginfo;
1095 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1096 const char *symref = NULL;
1097
1098 if (log && S_ISLNK(loginfo.st_mode))
1099 return error("reflog for %s is a symlink", oldref);
1100
1101 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1102 if (flag & REF_ISSYMREF)
1103 return error("refname %s is a symbolic ref, renaming it is not supported",
1104 oldref);
1105 if (!symref)
1106 return error("refname %s not found", oldref);
1107
1108 if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
1109 return 1;
1110
1111 if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
1112 return 1;
1113
1114 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
1115 if (!lock)
1116 return error("unable to lock %s", renamed_ref);
1117 lock->force_write = 1;
1118 if (write_ref_sha1(lock, orig_sha1, logmsg))
1119 return error("unable to save current sha1 in %s", renamed_ref);
1120
1121 if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
1122 return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
1123 oldref, strerror(errno));
1124
1125 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1126 error("unable to delete old %s", oldref);
1127 goto rollback;
1128 }
1129
1130 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1131 if (errno==EISDIR) {
1132 if (remove_empty_directories(git_path("%s", newref))) {
1133 error("Directory not empty: %s", newref);
1134 goto rollback;
1135 }
1136 } else {
1137 error("unable to delete existing %s", newref);
1138 goto rollback;
1139 }
1140 }
1141
1142 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1143 error("unable to create directory for %s", newref);
1144 goto rollback;
1145 }
1146
1147 retry:
1148 if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
1149 if (errno==EISDIR || errno==ENOTDIR) {
1150 /*
1151 * rename(a, b) when b is an existing
1152 * directory ought to result in ISDIR, but
1153 * Solaris 5.8 gives ENOTDIR. Sheesh.
1154 */
1155 if (remove_empty_directories(git_path("logs/%s", newref))) {
1156 error("Directory not empty: logs/%s", newref);
1157 goto rollback;
1158 }
1159 goto retry;
1160 } else {
1161 error("unable to move logfile tmp-renamed-log to logs/%s: %s",
1162 newref, strerror(errno));
1163 goto rollback;
1164 }
1165 }
1166 logmoved = log;
1167
1168 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1169 if (!lock) {
1170 error("unable to lock %s for update", newref);
1171 goto rollback;
1172 }
1173 lock->force_write = 1;
1174 hashcpy(lock->old_sha1, orig_sha1);
1175 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1176 error("unable to write current sha1 into %s", newref);
1177 goto rollback;
1178 }
1179
1180 return 0;
1181
1182 rollback:
1183 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1184 if (!lock) {
1185 error("unable to lock %s for rollback", oldref);
1186 goto rollbacklog;
1187 }
1188
1189 lock->force_write = 1;
1190 flag = log_all_ref_updates;
1191 log_all_ref_updates = 0;
1192 if (write_ref_sha1(lock, orig_sha1, NULL))
1193 error("unable to write current sha1 into %s", oldref);
1194 log_all_ref_updates = flag;
1195
1196 rollbacklog:
1197 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1198 error("unable to restore logfile %s from %s: %s",
1199 oldref, newref, strerror(errno));
1200 if (!logmoved && log &&
1201 rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
1202 error("unable to restore logfile %s from tmp-renamed-log: %s",
1203 oldref, strerror(errno));
1204
1205 return 1;
1206 }
1207
1208 int close_ref(struct ref_lock *lock)
1209 {
1210 if (close_lock_file(lock->lk))
1211 return -1;
1212 lock->lock_fd = -1;
1213 return 0;
1214 }
1215
1216 int commit_ref(struct ref_lock *lock)
1217 {
1218 if (commit_lock_file(lock->lk))
1219 return -1;
1220 lock->lock_fd = -1;
1221 return 0;
1222 }
1223
1224 void unlock_ref(struct ref_lock *lock)
1225 {
1226 /* Do not free lock->lk -- atexit() still looks at them */
1227 if (lock->lk)
1228 rollback_lock_file(lock->lk);
1229 free(lock->ref_name);
1230 free(lock->orig_ref_name);
1231 free(lock);
1232 }
1233
1234 /*
1235 * copy the reflog message msg to buf, which has been allocated sufficiently
1236 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1237 * because reflog file is one line per entry.
1238 */
1239 static int copy_msg(char *buf, const char *msg)
1240 {
1241 char *cp = buf;
1242 char c;
1243 int wasspace = 1;
1244
1245 *cp++ = '\t';
1246 while ((c = *msg++)) {
1247 if (wasspace && isspace(c))
1248 continue;
1249 wasspace = isspace(c);
1250 if (wasspace)
1251 c = ' ';
1252 *cp++ = c;
1253 }
1254 while (buf < cp && isspace(cp[-1]))
1255 cp--;
1256 *cp++ = '\n';
1257 return cp - buf;
1258 }
1259
1260 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1261 const unsigned char *new_sha1, const char *msg)
1262 {
1263 int logfd, written, oflags = O_APPEND | O_WRONLY;
1264 unsigned maxlen, len;
1265 int msglen;
1266 char log_file[PATH_MAX];
1267 char *logrec;
1268 const char *committer;
1269
1270 if (log_all_ref_updates < 0)
1271 log_all_ref_updates = !is_bare_repository();
1272
1273 git_snpath(log_file, sizeof(log_file), "logs/%s", ref_name);
1274
1275 if (log_all_ref_updates &&
1276 (!prefixcmp(ref_name, "refs/heads/") ||
1277 !prefixcmp(ref_name, "refs/remotes/") ||
1278 !strcmp(ref_name, "HEAD"))) {
1279 if (safe_create_leading_directories(log_file) < 0)
1280 return error("unable to create directory for %s",
1281 log_file);
1282 oflags |= O_CREAT;
1283 }
1284
1285 logfd = open(log_file, oflags, 0666);
1286 if (logfd < 0) {
1287 if (!(oflags & O_CREAT) && errno == ENOENT)
1288 return 0;
1289
1290 if ((oflags & O_CREAT) && errno == EISDIR) {
1291 if (remove_empty_directories(log_file)) {
1292 return error("There are still logs under '%s'",
1293 log_file);
1294 }
1295 logfd = open(log_file, oflags, 0666);
1296 }
1297
1298 if (logfd < 0)
1299 return error("Unable to append to %s: %s",
1300 log_file, strerror(errno));
1301 }
1302
1303 adjust_shared_perm(log_file);
1304
1305 msglen = msg ? strlen(msg) : 0;
1306 committer = git_committer_info(0);
1307 maxlen = strlen(committer) + msglen + 100;
1308 logrec = xmalloc(maxlen);
1309 len = sprintf(logrec, "%s %s %s\n",
1310 sha1_to_hex(old_sha1),
1311 sha1_to_hex(new_sha1),
1312 committer);
1313 if (msglen)
1314 len += copy_msg(logrec + len - 1, msg) - 1;
1315 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1316 free(logrec);
1317 if (close(logfd) != 0 || written != len)
1318 return error("Unable to append to %s", log_file);
1319 return 0;
1320 }
1321
1322 static int is_branch(const char *refname)
1323 {
1324 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1325 }
1326
1327 int write_ref_sha1(struct ref_lock *lock,
1328 const unsigned char *sha1, const char *logmsg)
1329 {
1330 static char term = '\n';
1331 struct object *o;
1332
1333 if (!lock)
1334 return -1;
1335 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1336 unlock_ref(lock);
1337 return 0;
1338 }
1339 o = parse_object(sha1);
1340 if (!o) {
1341 error("Trying to write ref %s with nonexistant object %s",
1342 lock->ref_name, sha1_to_hex(sha1));
1343 unlock_ref(lock);
1344 return -1;
1345 }
1346 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1347 error("Trying to write non-commit object %s to branch %s",
1348 sha1_to_hex(sha1), lock->ref_name);
1349 unlock_ref(lock);
1350 return -1;
1351 }
1352 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1353 write_in_full(lock->lock_fd, &term, 1) != 1
1354 || close_ref(lock) < 0) {
1355 error("Couldn't write %s", lock->lk->filename);
1356 unlock_ref(lock);
1357 return -1;
1358 }
1359 invalidate_cached_refs();
1360 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1361 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1362 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1363 unlock_ref(lock);
1364 return -1;
1365 }
1366 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1367 /*
1368 * Special hack: If a branch is updated directly and HEAD
1369 * points to it (may happen on the remote side of a push
1370 * for example) then logically the HEAD reflog should be
1371 * updated too.
1372 * A generic solution implies reverse symref information,
1373 * but finding all symrefs pointing to the given branch
1374 * would be rather costly for this rare event (the direct
1375 * update of a branch) to be worth it. So let's cheat and
1376 * check with HEAD only which should cover 99% of all usage
1377 * scenarios (even 100% of the default ones).
1378 */
1379 unsigned char head_sha1[20];
1380 int head_flag;
1381 const char *head_ref;
1382 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1383 if (head_ref && (head_flag & REF_ISSYMREF) &&
1384 !strcmp(head_ref, lock->ref_name))
1385 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1386 }
1387 if (commit_ref(lock)) {
1388 error("Couldn't set %s", lock->ref_name);
1389 unlock_ref(lock);
1390 return -1;
1391 }
1392 unlock_ref(lock);
1393 return 0;
1394 }
1395
1396 int create_symref(const char *ref_target, const char *refs_heads_master,
1397 const char *logmsg)
1398 {
1399 const char *lockpath;
1400 char ref[1000];
1401 int fd, len, written;
1402 char *git_HEAD = git_pathdup("%s", ref_target);
1403 unsigned char old_sha1[20], new_sha1[20];
1404
1405 if (logmsg && read_ref(ref_target, old_sha1))
1406 hashclr(old_sha1);
1407
1408 if (safe_create_leading_directories(git_HEAD) < 0)
1409 return error("unable to create directory for %s", git_HEAD);
1410
1411 #ifndef NO_SYMLINK_HEAD
1412 if (prefer_symlink_refs) {
1413 unlink(git_HEAD);
1414 if (!symlink(refs_heads_master, git_HEAD))
1415 goto done;
1416 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1417 }
1418 #endif
1419
1420 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1421 if (sizeof(ref) <= len) {
1422 error("refname too long: %s", refs_heads_master);
1423 goto error_free_return;
1424 }
1425 lockpath = mkpath("%s.lock", git_HEAD);
1426 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1427 if (fd < 0) {
1428 error("Unable to open %s for writing", lockpath);
1429 goto error_free_return;
1430 }
1431 written = write_in_full(fd, ref, len);
1432 if (close(fd) != 0 || written != len) {
1433 error("Unable to write to %s", lockpath);
1434 goto error_unlink_return;
1435 }
1436 if (rename(lockpath, git_HEAD) < 0) {
1437 error("Unable to create %s", git_HEAD);
1438 goto error_unlink_return;
1439 }
1440 if (adjust_shared_perm(git_HEAD)) {
1441 error("Unable to fix permissions on %s", lockpath);
1442 error_unlink_return:
1443 unlink_or_warn(lockpath);
1444 error_free_return:
1445 free(git_HEAD);
1446 return -1;
1447 }
1448
1449 #ifndef NO_SYMLINK_HEAD
1450 done:
1451 #endif
1452 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1453 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1454
1455 free(git_HEAD);
1456 return 0;
1457 }
1458
1459 static char *ref_msg(const char *line, const char *endp)
1460 {
1461 const char *ep;
1462 line += 82;
1463 ep = memchr(line, '\n', endp - line);
1464 if (!ep)
1465 ep = endp;
1466 return xmemdupz(line, ep - line);
1467 }
1468
1469 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)
1470 {
1471 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1472 char *tz_c;
1473 int logfd, tz, reccnt = 0;
1474 struct stat st;
1475 unsigned long date;
1476 unsigned char logged_sha1[20];
1477 void *log_mapped;
1478 size_t mapsz;
1479
1480 logfile = git_path("logs/%s", ref);
1481 logfd = open(logfile, O_RDONLY, 0);
1482 if (logfd < 0)
1483 die_errno("Unable to read log '%s'", logfile);
1484 fstat(logfd, &st);
1485 if (!st.st_size)
1486 die("Log %s is empty.", logfile);
1487 mapsz = xsize_t(st.st_size);
1488 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1489 logdata = log_mapped;
1490 close(logfd);
1491
1492 lastrec = NULL;
1493 rec = logend = logdata + st.st_size;
1494 while (logdata < rec) {
1495 reccnt++;
1496 if (logdata < rec && *(rec-1) == '\n')
1497 rec--;
1498 lastgt = NULL;
1499 while (logdata < rec && *(rec-1) != '\n') {
1500 rec--;
1501 if (*rec == '>')
1502 lastgt = rec;
1503 }
1504 if (!lastgt)
1505 die("Log %s is corrupt.", logfile);
1506 date = strtoul(lastgt + 1, &tz_c, 10);
1507 if (date <= at_time || cnt == 0) {
1508 tz = strtoul(tz_c, NULL, 10);
1509 if (msg)
1510 *msg = ref_msg(rec, logend);
1511 if (cutoff_time)
1512 *cutoff_time = date;
1513 if (cutoff_tz)
1514 *cutoff_tz = tz;
1515 if (cutoff_cnt)
1516 *cutoff_cnt = reccnt - 1;
1517 if (lastrec) {
1518 if (get_sha1_hex(lastrec, logged_sha1))
1519 die("Log %s is corrupt.", logfile);
1520 if (get_sha1_hex(rec + 41, sha1))
1521 die("Log %s is corrupt.", logfile);
1522 if (hashcmp(logged_sha1, sha1)) {
1523 warning("Log %s has gap after %s.",
1524 logfile, show_date(date, tz, DATE_RFC2822));
1525 }
1526 }
1527 else if (date == at_time) {
1528 if (get_sha1_hex(rec + 41, sha1))
1529 die("Log %s is corrupt.", logfile);
1530 }
1531 else {
1532 if (get_sha1_hex(rec + 41, logged_sha1))
1533 die("Log %s is corrupt.", logfile);
1534 if (hashcmp(logged_sha1, sha1)) {
1535 warning("Log %s unexpectedly ended on %s.",
1536 logfile, show_date(date, tz, DATE_RFC2822));
1537 }
1538 }
1539 munmap(log_mapped, mapsz);
1540 return 0;
1541 }
1542 lastrec = rec;
1543 if (cnt > 0)
1544 cnt--;
1545 }
1546
1547 rec = logdata;
1548 while (rec < logend && *rec != '>' && *rec != '\n')
1549 rec++;
1550 if (rec == logend || *rec == '\n')
1551 die("Log %s is corrupt.", logfile);
1552 date = strtoul(rec + 1, &tz_c, 10);
1553 tz = strtoul(tz_c, NULL, 10);
1554 if (get_sha1_hex(logdata, sha1))
1555 die("Log %s is corrupt.", logfile);
1556 if (is_null_sha1(sha1)) {
1557 if (get_sha1_hex(logdata + 41, sha1))
1558 die("Log %s is corrupt.", logfile);
1559 }
1560 if (msg)
1561 *msg = ref_msg(logdata, logend);
1562 munmap(log_mapped, mapsz);
1563
1564 if (cutoff_time)
1565 *cutoff_time = date;
1566 if (cutoff_tz)
1567 *cutoff_tz = tz;
1568 if (cutoff_cnt)
1569 *cutoff_cnt = reccnt;
1570 return 1;
1571 }
1572
1573 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1574 {
1575 const char *logfile;
1576 FILE *logfp;
1577 char buf[1024];
1578 int ret = 0;
1579
1580 logfile = git_path("logs/%s", ref);
1581 logfp = fopen(logfile, "r");
1582 if (!logfp)
1583 return -1;
1584
1585 if (ofs) {
1586 struct stat statbuf;
1587 if (fstat(fileno(logfp), &statbuf) ||
1588 statbuf.st_size < ofs ||
1589 fseek(logfp, -ofs, SEEK_END) ||
1590 fgets(buf, sizeof(buf), logfp)) {
1591 fclose(logfp);
1592 return -1;
1593 }
1594 }
1595
1596 while (fgets(buf, sizeof(buf), logfp)) {
1597 unsigned char osha1[20], nsha1[20];
1598 char *email_end, *message;
1599 unsigned long timestamp;
1600 int len, tz;
1601
1602 /* old SP new SP name <email> SP time TAB msg LF */
1603 len = strlen(buf);
1604 if (len < 83 || buf[len-1] != '\n' ||
1605 get_sha1_hex(buf, osha1) || buf[40] != ' ' ||
1606 get_sha1_hex(buf + 41, nsha1) || buf[81] != ' ' ||
1607 !(email_end = strchr(buf + 82, '>')) ||
1608 email_end[1] != ' ' ||
1609 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1610 !message || message[0] != ' ' ||
1611 (message[1] != '+' && message[1] != '-') ||
1612 !isdigit(message[2]) || !isdigit(message[3]) ||
1613 !isdigit(message[4]) || !isdigit(message[5]))
1614 continue; /* corrupt? */
1615 email_end[1] = '\0';
1616 tz = strtol(message + 1, NULL, 10);
1617 if (message[6] != '\t')
1618 message += 6;
1619 else
1620 message += 7;
1621 ret = fn(osha1, nsha1, buf+82, timestamp, tz, message, cb_data);
1622 if (ret)
1623 break;
1624 }
1625 fclose(logfp);
1626 return ret;
1627 }
1628
1629 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1630 {
1631 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1632 }
1633
1634 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1635 {
1636 DIR *dir = opendir(git_path("logs/%s", base));
1637 int retval = 0;
1638
1639 if (dir) {
1640 struct dirent *de;
1641 int baselen = strlen(base);
1642 char *log = xmalloc(baselen + 257);
1643
1644 memcpy(log, base, baselen);
1645 if (baselen && base[baselen-1] != '/')
1646 log[baselen++] = '/';
1647
1648 while ((de = readdir(dir)) != NULL) {
1649 struct stat st;
1650 int namelen;
1651
1652 if (de->d_name[0] == '.')
1653 continue;
1654 namelen = strlen(de->d_name);
1655 if (namelen > 255)
1656 continue;
1657 if (has_extension(de->d_name, ".lock"))
1658 continue;
1659 memcpy(log + baselen, de->d_name, namelen+1);
1660 if (stat(git_path("logs/%s", log), &st) < 0)
1661 continue;
1662 if (S_ISDIR(st.st_mode)) {
1663 retval = do_for_each_reflog(log, fn, cb_data);
1664 } else {
1665 unsigned char sha1[20];
1666 if (!resolve_ref(log, sha1, 0, NULL))
1667 retval = error("bad ref for %s", log);
1668 else
1669 retval = fn(log, sha1, 0, cb_data);
1670 }
1671 if (retval)
1672 break;
1673 }
1674 free(log);
1675 closedir(dir);
1676 }
1677 else if (*base)
1678 return errno;
1679 return retval;
1680 }
1681
1682 int for_each_reflog(each_ref_fn fn, void *cb_data)
1683 {
1684 return do_for_each_reflog("", fn, cb_data);
1685 }
1686
1687 int update_ref(const char *action, const char *refname,
1688 const unsigned char *sha1, const unsigned char *oldval,
1689 int flags, enum action_on_err onerr)
1690 {
1691 static struct ref_lock *lock;
1692 lock = lock_any_ref_for_update(refname, oldval, flags);
1693 if (!lock) {
1694 const char *str = "Cannot lock the ref '%s'.";
1695 switch (onerr) {
1696 case MSG_ON_ERR: error(str, refname); break;
1697 case DIE_ON_ERR: die(str, refname); break;
1698 case QUIET_ON_ERR: break;
1699 }
1700 return 1;
1701 }
1702 if (write_ref_sha1(lock, sha1, action) < 0) {
1703 const char *str = "Cannot update the ref '%s'.";
1704 switch (onerr) {
1705 case MSG_ON_ERR: error(str, refname); break;
1706 case DIE_ON_ERR: die(str, refname); break;
1707 case QUIET_ON_ERR: break;
1708 }
1709 return 1;
1710 }
1711 return 0;
1712 }
1713
1714 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1715 {
1716 for ( ; list; list = list->next)
1717 if (!strcmp(list->name, name))
1718 return (struct ref *)list;
1719 return NULL;
1720 }
1721
1722 /*
1723 * generate a format suitable for scanf from a ref_rev_parse_rules
1724 * rule, that is replace the "%.*s" spec with a "%s" spec
1725 */
1726 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1727 {
1728 char *spec;
1729
1730 spec = strstr(rule, "%.*s");
1731 if (!spec || strstr(spec + 4, "%.*s"))
1732 die("invalid rule in ref_rev_parse_rules: %s", rule);
1733
1734 /* copy all until spec */
1735 strncpy(scanf_fmt, rule, spec - rule);
1736 scanf_fmt[spec - rule] = '\0';
1737 /* copy new spec */
1738 strcat(scanf_fmt, "%s");
1739 /* copy remaining rule */
1740 strcat(scanf_fmt, spec + 4);
1741
1742 return;
1743 }
1744
1745 char *shorten_unambiguous_ref(const char *ref, int strict)
1746 {
1747 int i;
1748 static char **scanf_fmts;
1749 static int nr_rules;
1750 char *short_name;
1751
1752 /* pre generate scanf formats from ref_rev_parse_rules[] */
1753 if (!nr_rules) {
1754 size_t total_len = 0;
1755
1756 /* the rule list is NULL terminated, count them first */
1757 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1758 /* no +1 because strlen("%s") < strlen("%.*s") */
1759 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1760
1761 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1762
1763 total_len = 0;
1764 for (i = 0; i < nr_rules; i++) {
1765 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1766 + total_len;
1767 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1768 total_len += strlen(ref_rev_parse_rules[i]);
1769 }
1770 }
1771
1772 /* bail out if there are no rules */
1773 if (!nr_rules)
1774 return xstrdup(ref);
1775
1776 /* buffer for scanf result, at most ref must fit */
1777 short_name = xstrdup(ref);
1778
1779 /* skip first rule, it will always match */
1780 for (i = nr_rules - 1; i > 0 ; --i) {
1781 int j;
1782 int rules_to_fail = i;
1783 int short_name_len;
1784
1785 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1786 continue;
1787
1788 short_name_len = strlen(short_name);
1789
1790 /*
1791 * in strict mode, all (except the matched one) rules
1792 * must fail to resolve to a valid non-ambiguous ref
1793 */
1794 if (strict)
1795 rules_to_fail = nr_rules;
1796
1797 /*
1798 * check if the short name resolves to a valid ref,
1799 * but use only rules prior to the matched one
1800 */
1801 for (j = 0; j < rules_to_fail; j++) {
1802 const char *rule = ref_rev_parse_rules[j];
1803 unsigned char short_objectname[20];
1804 char refname[PATH_MAX];
1805
1806 /* skip matched rule */
1807 if (i == j)
1808 continue;
1809
1810 /*
1811 * the short name is ambiguous, if it resolves
1812 * (with this previous rule) to a valid ref
1813 * read_ref() returns 0 on success
1814 */
1815 mksnpath(refname, sizeof(refname),
1816 rule, short_name_len, short_name);
1817 if (!read_ref(refname, short_objectname))
1818 break;
1819 }
1820
1821 /*
1822 * short name is non-ambiguous if all previous rules
1823 * haven't resolved to a valid ref
1824 */
1825 if (j == rules_to_fail)
1826 return short_name;
1827 }
1828
1829 free(short_name);
1830 return xstrdup(ref);
1831 }