rev-parse --glob
[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(each_ref_fn fn, const char *pattern, void *cb_data)
694 {
695 struct strbuf real_pattern = STRBUF_INIT;
696 struct ref_filter filter;
697 const char *has_glob_specials;
698 int ret;
699
700 if (prefixcmp(pattern, "refs/"))
701 strbuf_addstr(&real_pattern, "refs/");
702 strbuf_addstr(&real_pattern, pattern);
703
704 has_glob_specials = strpbrk(pattern, "?*[");
705 if (!has_glob_specials) {
706 /* Append impiled '/' '*' if not present. */
707 if (real_pattern.buf[real_pattern.len - 1] != '/')
708 strbuf_addch(&real_pattern, '/');
709 /* No need to check for '*', there is none. */
710 strbuf_addch(&real_pattern, '*');
711 }
712
713 filter.pattern = real_pattern.buf;
714 filter.fn = fn;
715 filter.cb_data = cb_data;
716 ret = for_each_ref(filter_refs, &filter);
717
718 strbuf_release(&real_pattern);
719 return ret;
720 }
721
722 int for_each_rawref(each_ref_fn fn, void *cb_data)
723 {
724 return do_for_each_ref("refs/", fn, 0,
725 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
726 }
727
728 /*
729 * Make sure "ref" is something reasonable to have under ".git/refs/";
730 * We do not like it if:
731 *
732 * - any path component of it begins with ".", or
733 * - it has double dots "..", or
734 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
735 * - it ends with a "/".
736 * - it ends with ".lock"
737 * - it contains a "\" (backslash)
738 */
739
740 static inline int bad_ref_char(int ch)
741 {
742 if (((unsigned) ch) <= ' ' ||
743 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
744 return 1;
745 /* 2.13 Pattern Matching Notation */
746 if (ch == '?' || ch == '[') /* Unsupported */
747 return 1;
748 if (ch == '*') /* Supported at the end */
749 return 2;
750 return 0;
751 }
752
753 int check_ref_format(const char *ref)
754 {
755 int ch, level, bad_type, last;
756 int ret = CHECK_REF_FORMAT_OK;
757 const char *cp = ref;
758
759 level = 0;
760 while (1) {
761 while ((ch = *cp++) == '/')
762 ; /* tolerate duplicated slashes */
763 if (!ch)
764 /* should not end with slashes */
765 return CHECK_REF_FORMAT_ERROR;
766
767 /* we are at the beginning of the path component */
768 if (ch == '.')
769 return CHECK_REF_FORMAT_ERROR;
770 bad_type = bad_ref_char(ch);
771 if (bad_type) {
772 if (bad_type == 2 && (!*cp || *cp == '/') &&
773 ret == CHECK_REF_FORMAT_OK)
774 ret = CHECK_REF_FORMAT_WILDCARD;
775 else
776 return CHECK_REF_FORMAT_ERROR;
777 }
778
779 last = ch;
780 /* scan the rest of the path component */
781 while ((ch = *cp++) != 0) {
782 bad_type = bad_ref_char(ch);
783 if (bad_type)
784 return CHECK_REF_FORMAT_ERROR;
785 if (ch == '/')
786 break;
787 if (last == '.' && ch == '.')
788 return CHECK_REF_FORMAT_ERROR;
789 if (last == '@' && ch == '{')
790 return CHECK_REF_FORMAT_ERROR;
791 last = ch;
792 }
793 level++;
794 if (!ch) {
795 if (ref <= cp - 2 && cp[-2] == '.')
796 return CHECK_REF_FORMAT_ERROR;
797 if (level < 2)
798 return CHECK_REF_FORMAT_ONELEVEL;
799 if (has_extension(ref, ".lock"))
800 return CHECK_REF_FORMAT_ERROR;
801 return ret;
802 }
803 }
804 }
805
806 const char *prettify_refname(const char *name)
807 {
808 return name + (
809 !prefixcmp(name, "refs/heads/") ? 11 :
810 !prefixcmp(name, "refs/tags/") ? 10 :
811 !prefixcmp(name, "refs/remotes/") ? 13 :
812 0);
813 }
814
815 const char *ref_rev_parse_rules[] = {
816 "%.*s",
817 "refs/%.*s",
818 "refs/tags/%.*s",
819 "refs/heads/%.*s",
820 "refs/remotes/%.*s",
821 "refs/remotes/%.*s/HEAD",
822 NULL
823 };
824
825 const char *ref_fetch_rules[] = {
826 "%.*s",
827 "refs/%.*s",
828 "refs/heads/%.*s",
829 NULL
830 };
831
832 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
833 {
834 const char **p;
835 const int abbrev_name_len = strlen(abbrev_name);
836
837 for (p = rules; *p; p++) {
838 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
839 return 1;
840 }
841 }
842
843 return 0;
844 }
845
846 static struct ref_lock *verify_lock(struct ref_lock *lock,
847 const unsigned char *old_sha1, int mustexist)
848 {
849 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
850 error("Can't verify ref %s", lock->ref_name);
851 unlock_ref(lock);
852 return NULL;
853 }
854 if (hashcmp(lock->old_sha1, old_sha1)) {
855 error("Ref %s is at %s but expected %s", lock->ref_name,
856 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
857 unlock_ref(lock);
858 return NULL;
859 }
860 return lock;
861 }
862
863 static int remove_empty_directories(const char *file)
864 {
865 /* we want to create a file but there is a directory there;
866 * if that is an empty directory (or a directory that contains
867 * only empty directories), remove them.
868 */
869 struct strbuf path;
870 int result;
871
872 strbuf_init(&path, 20);
873 strbuf_addstr(&path, file);
874
875 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
876
877 strbuf_release(&path);
878
879 return result;
880 }
881
882 static int is_refname_available(const char *ref, const char *oldref,
883 struct ref_list *list, int quiet)
884 {
885 int namlen = strlen(ref); /* e.g. 'foo/bar' */
886 while (list) {
887 /* list->name could be 'foo' or 'foo/bar/baz' */
888 if (!oldref || strcmp(oldref, list->name)) {
889 int len = strlen(list->name);
890 int cmplen = (namlen < len) ? namlen : len;
891 const char *lead = (namlen < len) ? list->name : ref;
892 if (!strncmp(ref, list->name, cmplen) &&
893 lead[cmplen] == '/') {
894 if (!quiet)
895 error("'%s' exists; cannot create '%s'",
896 list->name, ref);
897 return 0;
898 }
899 }
900 list = list->next;
901 }
902 return 1;
903 }
904
905 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
906 {
907 char *ref_file;
908 const char *orig_ref = ref;
909 struct ref_lock *lock;
910 int last_errno = 0;
911 int type, lflags;
912 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
913 int missing = 0;
914
915 lock = xcalloc(1, sizeof(struct ref_lock));
916 lock->lock_fd = -1;
917
918 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
919 if (!ref && errno == EISDIR) {
920 /* we are trying to lock foo but we used to
921 * have foo/bar which now does not exist;
922 * it is normal for the empty directory 'foo'
923 * to remain.
924 */
925 ref_file = git_path("%s", orig_ref);
926 if (remove_empty_directories(ref_file)) {
927 last_errno = errno;
928 error("there are still refs under '%s'", orig_ref);
929 goto error_return;
930 }
931 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
932 }
933 if (type_p)
934 *type_p = type;
935 if (!ref) {
936 last_errno = errno;
937 error("unable to resolve reference %s: %s",
938 orig_ref, strerror(errno));
939 goto error_return;
940 }
941 missing = is_null_sha1(lock->old_sha1);
942 /* When the ref did not exist and we are creating it,
943 * make sure there is no existing ref that is packed
944 * whose name begins with our refname, nor a ref whose
945 * name is a proper prefix of our refname.
946 */
947 if (missing &&
948 !is_refname_available(ref, NULL, get_packed_refs(), 0)) {
949 last_errno = ENOTDIR;
950 goto error_return;
951 }
952
953 lock->lk = xcalloc(1, sizeof(struct lock_file));
954
955 lflags = LOCK_DIE_ON_ERROR;
956 if (flags & REF_NODEREF) {
957 ref = orig_ref;
958 lflags |= LOCK_NODEREF;
959 }
960 lock->ref_name = xstrdup(ref);
961 lock->orig_ref_name = xstrdup(orig_ref);
962 ref_file = git_path("%s", ref);
963 if (missing)
964 lock->force_write = 1;
965 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
966 lock->force_write = 1;
967
968 if (safe_create_leading_directories(ref_file)) {
969 last_errno = errno;
970 error("unable to create directory for %s", ref_file);
971 goto error_return;
972 }
973
974 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
975 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
976
977 error_return:
978 unlock_ref(lock);
979 errno = last_errno;
980 return NULL;
981 }
982
983 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
984 {
985 char refpath[PATH_MAX];
986 if (check_ref_format(ref))
987 return NULL;
988 strcpy(refpath, mkpath("refs/%s", ref));
989 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
990 }
991
992 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
993 {
994 switch (check_ref_format(ref)) {
995 default:
996 return NULL;
997 case 0:
998 case CHECK_REF_FORMAT_ONELEVEL:
999 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1000 }
1001 }
1002
1003 static struct lock_file packlock;
1004
1005 static int repack_without_ref(const char *refname)
1006 {
1007 struct ref_list *list, *packed_ref_list;
1008 int fd;
1009 int found = 0;
1010
1011 packed_ref_list = get_packed_refs();
1012 for (list = packed_ref_list; list; list = list->next) {
1013 if (!strcmp(refname, list->name)) {
1014 found = 1;
1015 break;
1016 }
1017 }
1018 if (!found)
1019 return 0;
1020 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1021 if (fd < 0) {
1022 unable_to_lock_error(git_path("packed-refs"), errno);
1023 return error("cannot delete '%s' from packed refs", refname);
1024 }
1025
1026 for (list = packed_ref_list; list; list = list->next) {
1027 char line[PATH_MAX + 100];
1028 int len;
1029
1030 if (!strcmp(refname, list->name))
1031 continue;
1032 len = snprintf(line, sizeof(line), "%s %s\n",
1033 sha1_to_hex(list->sha1), list->name);
1034 /* this should not happen but just being defensive */
1035 if (len > sizeof(line))
1036 die("too long a refname '%s'", list->name);
1037 write_or_die(fd, line, len);
1038 }
1039 return commit_lock_file(&packlock);
1040 }
1041
1042 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1043 {
1044 struct ref_lock *lock;
1045 int err, i = 0, ret = 0, flag = 0;
1046
1047 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1048 if (!lock)
1049 return 1;
1050 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1051 /* loose */
1052 const char *path;
1053
1054 if (!(delopt & REF_NODEREF)) {
1055 i = strlen(lock->lk->filename) - 5; /* .lock */
1056 lock->lk->filename[i] = 0;
1057 path = lock->lk->filename;
1058 } else {
1059 path = git_path("%s", refname);
1060 }
1061 err = unlink_or_warn(path);
1062 if (err && errno != ENOENT)
1063 ret = 1;
1064
1065 if (!(delopt & REF_NODEREF))
1066 lock->lk->filename[i] = '.';
1067 }
1068 /* removing the loose one could have resurrected an earlier
1069 * packed one. Also, if it was not loose we need to repack
1070 * without it.
1071 */
1072 ret |= repack_without_ref(refname);
1073
1074 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1075 invalidate_cached_refs();
1076 unlock_ref(lock);
1077 return ret;
1078 }
1079
1080 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1081 {
1082 static const char renamed_ref[] = "RENAMED-REF";
1083 unsigned char sha1[20], orig_sha1[20];
1084 int flag = 0, logmoved = 0;
1085 struct ref_lock *lock;
1086 struct stat loginfo;
1087 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1088 const char *symref = NULL;
1089
1090 if (log && S_ISLNK(loginfo.st_mode))
1091 return error("reflog for %s is a symlink", oldref);
1092
1093 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1094 if (flag & REF_ISSYMREF)
1095 return error("refname %s is a symbolic ref, renaming it is not supported",
1096 oldref);
1097 if (!symref)
1098 return error("refname %s not found", oldref);
1099
1100 if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
1101 return 1;
1102
1103 if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
1104 return 1;
1105
1106 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
1107 if (!lock)
1108 return error("unable to lock %s", renamed_ref);
1109 lock->force_write = 1;
1110 if (write_ref_sha1(lock, orig_sha1, logmsg))
1111 return error("unable to save current sha1 in %s", renamed_ref);
1112
1113 if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
1114 return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
1115 oldref, strerror(errno));
1116
1117 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1118 error("unable to delete old %s", oldref);
1119 goto rollback;
1120 }
1121
1122 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1123 if (errno==EISDIR) {
1124 if (remove_empty_directories(git_path("%s", newref))) {
1125 error("Directory not empty: %s", newref);
1126 goto rollback;
1127 }
1128 } else {
1129 error("unable to delete existing %s", newref);
1130 goto rollback;
1131 }
1132 }
1133
1134 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1135 error("unable to create directory for %s", newref);
1136 goto rollback;
1137 }
1138
1139 retry:
1140 if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
1141 if (errno==EISDIR || errno==ENOTDIR) {
1142 /*
1143 * rename(a, b) when b is an existing
1144 * directory ought to result in ISDIR, but
1145 * Solaris 5.8 gives ENOTDIR. Sheesh.
1146 */
1147 if (remove_empty_directories(git_path("logs/%s", newref))) {
1148 error("Directory not empty: logs/%s", newref);
1149 goto rollback;
1150 }
1151 goto retry;
1152 } else {
1153 error("unable to move logfile tmp-renamed-log to logs/%s: %s",
1154 newref, strerror(errno));
1155 goto rollback;
1156 }
1157 }
1158 logmoved = log;
1159
1160 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1161 if (!lock) {
1162 error("unable to lock %s for update", newref);
1163 goto rollback;
1164 }
1165 lock->force_write = 1;
1166 hashcpy(lock->old_sha1, orig_sha1);
1167 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1168 error("unable to write current sha1 into %s", newref);
1169 goto rollback;
1170 }
1171
1172 return 0;
1173
1174 rollback:
1175 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1176 if (!lock) {
1177 error("unable to lock %s for rollback", oldref);
1178 goto rollbacklog;
1179 }
1180
1181 lock->force_write = 1;
1182 flag = log_all_ref_updates;
1183 log_all_ref_updates = 0;
1184 if (write_ref_sha1(lock, orig_sha1, NULL))
1185 error("unable to write current sha1 into %s", oldref);
1186 log_all_ref_updates = flag;
1187
1188 rollbacklog:
1189 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1190 error("unable to restore logfile %s from %s: %s",
1191 oldref, newref, strerror(errno));
1192 if (!logmoved && log &&
1193 rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
1194 error("unable to restore logfile %s from tmp-renamed-log: %s",
1195 oldref, strerror(errno));
1196
1197 return 1;
1198 }
1199
1200 int close_ref(struct ref_lock *lock)
1201 {
1202 if (close_lock_file(lock->lk))
1203 return -1;
1204 lock->lock_fd = -1;
1205 return 0;
1206 }
1207
1208 int commit_ref(struct ref_lock *lock)
1209 {
1210 if (commit_lock_file(lock->lk))
1211 return -1;
1212 lock->lock_fd = -1;
1213 return 0;
1214 }
1215
1216 void unlock_ref(struct ref_lock *lock)
1217 {
1218 /* Do not free lock->lk -- atexit() still looks at them */
1219 if (lock->lk)
1220 rollback_lock_file(lock->lk);
1221 free(lock->ref_name);
1222 free(lock->orig_ref_name);
1223 free(lock);
1224 }
1225
1226 /*
1227 * copy the reflog message msg to buf, which has been allocated sufficiently
1228 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1229 * because reflog file is one line per entry.
1230 */
1231 static int copy_msg(char *buf, const char *msg)
1232 {
1233 char *cp = buf;
1234 char c;
1235 int wasspace = 1;
1236
1237 *cp++ = '\t';
1238 while ((c = *msg++)) {
1239 if (wasspace && isspace(c))
1240 continue;
1241 wasspace = isspace(c);
1242 if (wasspace)
1243 c = ' ';
1244 *cp++ = c;
1245 }
1246 while (buf < cp && isspace(cp[-1]))
1247 cp--;
1248 *cp++ = '\n';
1249 return cp - buf;
1250 }
1251
1252 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1253 const unsigned char *new_sha1, const char *msg)
1254 {
1255 int logfd, written, oflags = O_APPEND | O_WRONLY;
1256 unsigned maxlen, len;
1257 int msglen;
1258 char log_file[PATH_MAX];
1259 char *logrec;
1260 const char *committer;
1261
1262 if (log_all_ref_updates < 0)
1263 log_all_ref_updates = !is_bare_repository();
1264
1265 git_snpath(log_file, sizeof(log_file), "logs/%s", ref_name);
1266
1267 if (log_all_ref_updates &&
1268 (!prefixcmp(ref_name, "refs/heads/") ||
1269 !prefixcmp(ref_name, "refs/remotes/") ||
1270 !strcmp(ref_name, "HEAD"))) {
1271 if (safe_create_leading_directories(log_file) < 0)
1272 return error("unable to create directory for %s",
1273 log_file);
1274 oflags |= O_CREAT;
1275 }
1276
1277 logfd = open(log_file, oflags, 0666);
1278 if (logfd < 0) {
1279 if (!(oflags & O_CREAT) && errno == ENOENT)
1280 return 0;
1281
1282 if ((oflags & O_CREAT) && errno == EISDIR) {
1283 if (remove_empty_directories(log_file)) {
1284 return error("There are still logs under '%s'",
1285 log_file);
1286 }
1287 logfd = open(log_file, oflags, 0666);
1288 }
1289
1290 if (logfd < 0)
1291 return error("Unable to append to %s: %s",
1292 log_file, strerror(errno));
1293 }
1294
1295 adjust_shared_perm(log_file);
1296
1297 msglen = msg ? strlen(msg) : 0;
1298 committer = git_committer_info(0);
1299 maxlen = strlen(committer) + msglen + 100;
1300 logrec = xmalloc(maxlen);
1301 len = sprintf(logrec, "%s %s %s\n",
1302 sha1_to_hex(old_sha1),
1303 sha1_to_hex(new_sha1),
1304 committer);
1305 if (msglen)
1306 len += copy_msg(logrec + len - 1, msg) - 1;
1307 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1308 free(logrec);
1309 if (close(logfd) != 0 || written != len)
1310 return error("Unable to append to %s", log_file);
1311 return 0;
1312 }
1313
1314 static int is_branch(const char *refname)
1315 {
1316 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1317 }
1318
1319 int write_ref_sha1(struct ref_lock *lock,
1320 const unsigned char *sha1, const char *logmsg)
1321 {
1322 static char term = '\n';
1323 struct object *o;
1324
1325 if (!lock)
1326 return -1;
1327 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1328 unlock_ref(lock);
1329 return 0;
1330 }
1331 o = parse_object(sha1);
1332 if (!o) {
1333 error("Trying to write ref %s with nonexistant object %s",
1334 lock->ref_name, sha1_to_hex(sha1));
1335 unlock_ref(lock);
1336 return -1;
1337 }
1338 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1339 error("Trying to write non-commit object %s to branch %s",
1340 sha1_to_hex(sha1), lock->ref_name);
1341 unlock_ref(lock);
1342 return -1;
1343 }
1344 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1345 write_in_full(lock->lock_fd, &term, 1) != 1
1346 || close_ref(lock) < 0) {
1347 error("Couldn't write %s", lock->lk->filename);
1348 unlock_ref(lock);
1349 return -1;
1350 }
1351 invalidate_cached_refs();
1352 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1353 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1354 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1355 unlock_ref(lock);
1356 return -1;
1357 }
1358 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1359 /*
1360 * Special hack: If a branch is updated directly and HEAD
1361 * points to it (may happen on the remote side of a push
1362 * for example) then logically the HEAD reflog should be
1363 * updated too.
1364 * A generic solution implies reverse symref information,
1365 * but finding all symrefs pointing to the given branch
1366 * would be rather costly for this rare event (the direct
1367 * update of a branch) to be worth it. So let's cheat and
1368 * check with HEAD only which should cover 99% of all usage
1369 * scenarios (even 100% of the default ones).
1370 */
1371 unsigned char head_sha1[20];
1372 int head_flag;
1373 const char *head_ref;
1374 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1375 if (head_ref && (head_flag & REF_ISSYMREF) &&
1376 !strcmp(head_ref, lock->ref_name))
1377 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1378 }
1379 if (commit_ref(lock)) {
1380 error("Couldn't set %s", lock->ref_name);
1381 unlock_ref(lock);
1382 return -1;
1383 }
1384 unlock_ref(lock);
1385 return 0;
1386 }
1387
1388 int create_symref(const char *ref_target, const char *refs_heads_master,
1389 const char *logmsg)
1390 {
1391 const char *lockpath;
1392 char ref[1000];
1393 int fd, len, written;
1394 char *git_HEAD = git_pathdup("%s", ref_target);
1395 unsigned char old_sha1[20], new_sha1[20];
1396
1397 if (logmsg && read_ref(ref_target, old_sha1))
1398 hashclr(old_sha1);
1399
1400 if (safe_create_leading_directories(git_HEAD) < 0)
1401 return error("unable to create directory for %s", git_HEAD);
1402
1403 #ifndef NO_SYMLINK_HEAD
1404 if (prefer_symlink_refs) {
1405 unlink(git_HEAD);
1406 if (!symlink(refs_heads_master, git_HEAD))
1407 goto done;
1408 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1409 }
1410 #endif
1411
1412 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1413 if (sizeof(ref) <= len) {
1414 error("refname too long: %s", refs_heads_master);
1415 goto error_free_return;
1416 }
1417 lockpath = mkpath("%s.lock", git_HEAD);
1418 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1419 if (fd < 0) {
1420 error("Unable to open %s for writing", lockpath);
1421 goto error_free_return;
1422 }
1423 written = write_in_full(fd, ref, len);
1424 if (close(fd) != 0 || written != len) {
1425 error("Unable to write to %s", lockpath);
1426 goto error_unlink_return;
1427 }
1428 if (rename(lockpath, git_HEAD) < 0) {
1429 error("Unable to create %s", git_HEAD);
1430 goto error_unlink_return;
1431 }
1432 if (adjust_shared_perm(git_HEAD)) {
1433 error("Unable to fix permissions on %s", lockpath);
1434 error_unlink_return:
1435 unlink_or_warn(lockpath);
1436 error_free_return:
1437 free(git_HEAD);
1438 return -1;
1439 }
1440
1441 #ifndef NO_SYMLINK_HEAD
1442 done:
1443 #endif
1444 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1445 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1446
1447 free(git_HEAD);
1448 return 0;
1449 }
1450
1451 static char *ref_msg(const char *line, const char *endp)
1452 {
1453 const char *ep;
1454 line += 82;
1455 ep = memchr(line, '\n', endp - line);
1456 if (!ep)
1457 ep = endp;
1458 return xmemdupz(line, ep - line);
1459 }
1460
1461 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)
1462 {
1463 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1464 char *tz_c;
1465 int logfd, tz, reccnt = 0;
1466 struct stat st;
1467 unsigned long date;
1468 unsigned char logged_sha1[20];
1469 void *log_mapped;
1470 size_t mapsz;
1471
1472 logfile = git_path("logs/%s", ref);
1473 logfd = open(logfile, O_RDONLY, 0);
1474 if (logfd < 0)
1475 die_errno("Unable to read log '%s'", logfile);
1476 fstat(logfd, &st);
1477 if (!st.st_size)
1478 die("Log %s is empty.", logfile);
1479 mapsz = xsize_t(st.st_size);
1480 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1481 logdata = log_mapped;
1482 close(logfd);
1483
1484 lastrec = NULL;
1485 rec = logend = logdata + st.st_size;
1486 while (logdata < rec) {
1487 reccnt++;
1488 if (logdata < rec && *(rec-1) == '\n')
1489 rec--;
1490 lastgt = NULL;
1491 while (logdata < rec && *(rec-1) != '\n') {
1492 rec--;
1493 if (*rec == '>')
1494 lastgt = rec;
1495 }
1496 if (!lastgt)
1497 die("Log %s is corrupt.", logfile);
1498 date = strtoul(lastgt + 1, &tz_c, 10);
1499 if (date <= at_time || cnt == 0) {
1500 tz = strtoul(tz_c, NULL, 10);
1501 if (msg)
1502 *msg = ref_msg(rec, logend);
1503 if (cutoff_time)
1504 *cutoff_time = date;
1505 if (cutoff_tz)
1506 *cutoff_tz = tz;
1507 if (cutoff_cnt)
1508 *cutoff_cnt = reccnt - 1;
1509 if (lastrec) {
1510 if (get_sha1_hex(lastrec, logged_sha1))
1511 die("Log %s is corrupt.", logfile);
1512 if (get_sha1_hex(rec + 41, sha1))
1513 die("Log %s is corrupt.", logfile);
1514 if (hashcmp(logged_sha1, sha1)) {
1515 warning("Log %s has gap after %s.",
1516 logfile, show_date(date, tz, DATE_RFC2822));
1517 }
1518 }
1519 else if (date == at_time) {
1520 if (get_sha1_hex(rec + 41, sha1))
1521 die("Log %s is corrupt.", logfile);
1522 }
1523 else {
1524 if (get_sha1_hex(rec + 41, logged_sha1))
1525 die("Log %s is corrupt.", logfile);
1526 if (hashcmp(logged_sha1, sha1)) {
1527 warning("Log %s unexpectedly ended on %s.",
1528 logfile, show_date(date, tz, DATE_RFC2822));
1529 }
1530 }
1531 munmap(log_mapped, mapsz);
1532 return 0;
1533 }
1534 lastrec = rec;
1535 if (cnt > 0)
1536 cnt--;
1537 }
1538
1539 rec = logdata;
1540 while (rec < logend && *rec != '>' && *rec != '\n')
1541 rec++;
1542 if (rec == logend || *rec == '\n')
1543 die("Log %s is corrupt.", logfile);
1544 date = strtoul(rec + 1, &tz_c, 10);
1545 tz = strtoul(tz_c, NULL, 10);
1546 if (get_sha1_hex(logdata, sha1))
1547 die("Log %s is corrupt.", logfile);
1548 if (is_null_sha1(sha1)) {
1549 if (get_sha1_hex(logdata + 41, sha1))
1550 die("Log %s is corrupt.", logfile);
1551 }
1552 if (msg)
1553 *msg = ref_msg(logdata, logend);
1554 munmap(log_mapped, mapsz);
1555
1556 if (cutoff_time)
1557 *cutoff_time = date;
1558 if (cutoff_tz)
1559 *cutoff_tz = tz;
1560 if (cutoff_cnt)
1561 *cutoff_cnt = reccnt;
1562 return 1;
1563 }
1564
1565 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1566 {
1567 const char *logfile;
1568 FILE *logfp;
1569 char buf[1024];
1570 int ret = 0;
1571
1572 logfile = git_path("logs/%s", ref);
1573 logfp = fopen(logfile, "r");
1574 if (!logfp)
1575 return -1;
1576
1577 if (ofs) {
1578 struct stat statbuf;
1579 if (fstat(fileno(logfp), &statbuf) ||
1580 statbuf.st_size < ofs ||
1581 fseek(logfp, -ofs, SEEK_END) ||
1582 fgets(buf, sizeof(buf), logfp)) {
1583 fclose(logfp);
1584 return -1;
1585 }
1586 }
1587
1588 while (fgets(buf, sizeof(buf), logfp)) {
1589 unsigned char osha1[20], nsha1[20];
1590 char *email_end, *message;
1591 unsigned long timestamp;
1592 int len, tz;
1593
1594 /* old SP new SP name <email> SP time TAB msg LF */
1595 len = strlen(buf);
1596 if (len < 83 || buf[len-1] != '\n' ||
1597 get_sha1_hex(buf, osha1) || buf[40] != ' ' ||
1598 get_sha1_hex(buf + 41, nsha1) || buf[81] != ' ' ||
1599 !(email_end = strchr(buf + 82, '>')) ||
1600 email_end[1] != ' ' ||
1601 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1602 !message || message[0] != ' ' ||
1603 (message[1] != '+' && message[1] != '-') ||
1604 !isdigit(message[2]) || !isdigit(message[3]) ||
1605 !isdigit(message[4]) || !isdigit(message[5]))
1606 continue; /* corrupt? */
1607 email_end[1] = '\0';
1608 tz = strtol(message + 1, NULL, 10);
1609 if (message[6] != '\t')
1610 message += 6;
1611 else
1612 message += 7;
1613 ret = fn(osha1, nsha1, buf+82, timestamp, tz, message, cb_data);
1614 if (ret)
1615 break;
1616 }
1617 fclose(logfp);
1618 return ret;
1619 }
1620
1621 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1622 {
1623 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1624 }
1625
1626 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1627 {
1628 DIR *dir = opendir(git_path("logs/%s", base));
1629 int retval = 0;
1630
1631 if (dir) {
1632 struct dirent *de;
1633 int baselen = strlen(base);
1634 char *log = xmalloc(baselen + 257);
1635
1636 memcpy(log, base, baselen);
1637 if (baselen && base[baselen-1] != '/')
1638 log[baselen++] = '/';
1639
1640 while ((de = readdir(dir)) != NULL) {
1641 struct stat st;
1642 int namelen;
1643
1644 if (de->d_name[0] == '.')
1645 continue;
1646 namelen = strlen(de->d_name);
1647 if (namelen > 255)
1648 continue;
1649 if (has_extension(de->d_name, ".lock"))
1650 continue;
1651 memcpy(log + baselen, de->d_name, namelen+1);
1652 if (stat(git_path("logs/%s", log), &st) < 0)
1653 continue;
1654 if (S_ISDIR(st.st_mode)) {
1655 retval = do_for_each_reflog(log, fn, cb_data);
1656 } else {
1657 unsigned char sha1[20];
1658 if (!resolve_ref(log, sha1, 0, NULL))
1659 retval = error("bad ref for %s", log);
1660 else
1661 retval = fn(log, sha1, 0, cb_data);
1662 }
1663 if (retval)
1664 break;
1665 }
1666 free(log);
1667 closedir(dir);
1668 }
1669 else if (*base)
1670 return errno;
1671 return retval;
1672 }
1673
1674 int for_each_reflog(each_ref_fn fn, void *cb_data)
1675 {
1676 return do_for_each_reflog("", fn, cb_data);
1677 }
1678
1679 int update_ref(const char *action, const char *refname,
1680 const unsigned char *sha1, const unsigned char *oldval,
1681 int flags, enum action_on_err onerr)
1682 {
1683 static struct ref_lock *lock;
1684 lock = lock_any_ref_for_update(refname, oldval, flags);
1685 if (!lock) {
1686 const char *str = "Cannot lock the ref '%s'.";
1687 switch (onerr) {
1688 case MSG_ON_ERR: error(str, refname); break;
1689 case DIE_ON_ERR: die(str, refname); break;
1690 case QUIET_ON_ERR: break;
1691 }
1692 return 1;
1693 }
1694 if (write_ref_sha1(lock, sha1, action) < 0) {
1695 const char *str = "Cannot update the ref '%s'.";
1696 switch (onerr) {
1697 case MSG_ON_ERR: error(str, refname); break;
1698 case DIE_ON_ERR: die(str, refname); break;
1699 case QUIET_ON_ERR: break;
1700 }
1701 return 1;
1702 }
1703 return 0;
1704 }
1705
1706 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1707 {
1708 for ( ; list; list = list->next)
1709 if (!strcmp(list->name, name))
1710 return (struct ref *)list;
1711 return NULL;
1712 }
1713
1714 /*
1715 * generate a format suitable for scanf from a ref_rev_parse_rules
1716 * rule, that is replace the "%.*s" spec with a "%s" spec
1717 */
1718 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1719 {
1720 char *spec;
1721
1722 spec = strstr(rule, "%.*s");
1723 if (!spec || strstr(spec + 4, "%.*s"))
1724 die("invalid rule in ref_rev_parse_rules: %s", rule);
1725
1726 /* copy all until spec */
1727 strncpy(scanf_fmt, rule, spec - rule);
1728 scanf_fmt[spec - rule] = '\0';
1729 /* copy new spec */
1730 strcat(scanf_fmt, "%s");
1731 /* copy remaining rule */
1732 strcat(scanf_fmt, spec + 4);
1733
1734 return;
1735 }
1736
1737 char *shorten_unambiguous_ref(const char *ref, int strict)
1738 {
1739 int i;
1740 static char **scanf_fmts;
1741 static int nr_rules;
1742 char *short_name;
1743
1744 /* pre generate scanf formats from ref_rev_parse_rules[] */
1745 if (!nr_rules) {
1746 size_t total_len = 0;
1747
1748 /* the rule list is NULL terminated, count them first */
1749 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1750 /* no +1 because strlen("%s") < strlen("%.*s") */
1751 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1752
1753 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1754
1755 total_len = 0;
1756 for (i = 0; i < nr_rules; i++) {
1757 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1758 + total_len;
1759 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1760 total_len += strlen(ref_rev_parse_rules[i]);
1761 }
1762 }
1763
1764 /* bail out if there are no rules */
1765 if (!nr_rules)
1766 return xstrdup(ref);
1767
1768 /* buffer for scanf result, at most ref must fit */
1769 short_name = xstrdup(ref);
1770
1771 /* skip first rule, it will always match */
1772 for (i = nr_rules - 1; i > 0 ; --i) {
1773 int j;
1774 int rules_to_fail = i;
1775 int short_name_len;
1776
1777 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1778 continue;
1779
1780 short_name_len = strlen(short_name);
1781
1782 /*
1783 * in strict mode, all (except the matched one) rules
1784 * must fail to resolve to a valid non-ambiguous ref
1785 */
1786 if (strict)
1787 rules_to_fail = nr_rules;
1788
1789 /*
1790 * check if the short name resolves to a valid ref,
1791 * but use only rules prior to the matched one
1792 */
1793 for (j = 0; j < rules_to_fail; j++) {
1794 const char *rule = ref_rev_parse_rules[j];
1795 unsigned char short_objectname[20];
1796 char refname[PATH_MAX];
1797
1798 /* skip matched rule */
1799 if (i == j)
1800 continue;
1801
1802 /*
1803 * the short name is ambiguous, if it resolves
1804 * (with this previous rule) to a valid ref
1805 * read_ref() returns 0 on success
1806 */
1807 mksnpath(refname, sizeof(refname),
1808 rule, short_name_len, short_name);
1809 if (!read_ref(refname, short_objectname))
1810 break;
1811 }
1812
1813 /*
1814 * short name is non-ambiguous if all previous rules
1815 * haven't resolved to a valid ref
1816 */
1817 if (j == rules_to_fail)
1818 return short_name;
1819 }
1820
1821 free(short_name);
1822 return xstrdup(ref);
1823 }