096b42c5e993193dd83a02128be4b90ebc59edd1
[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 #define REF_BROKEN 010
10
11 struct ref_list {
12 struct ref_list *next;
13 unsigned char flag; /* ISSYMREF? ISPACKED? */
14 unsigned char sha1[20];
15 unsigned char peeled[20];
16 char name[FLEX_ARRAY];
17 };
18
19 static const char *parse_ref_line(char *line, unsigned char *sha1)
20 {
21 /*
22 * 42: the answer to everything.
23 *
24 * In this case, it happens to be the answer to
25 * 40 (length of sha1 hex representation)
26 * +1 (space in between hex and name)
27 * +1 (newline at the end of the line)
28 */
29 int len = strlen(line) - 42;
30
31 if (len <= 0)
32 return NULL;
33 if (get_sha1_hex(line, sha1) < 0)
34 return NULL;
35 if (!isspace(line[40]))
36 return NULL;
37 line += 41;
38 if (isspace(*line))
39 return NULL;
40 if (line[len] != '\n')
41 return NULL;
42 line[len] = 0;
43
44 return line;
45 }
46
47 static struct ref_list *add_ref(const char *name, const unsigned char *sha1,
48 int flag, struct ref_list *list,
49 struct ref_list **new_entry)
50 {
51 int len;
52 struct ref_list *entry;
53
54 /* Allocate it and add it in.. */
55 len = strlen(name) + 1;
56 entry = xmalloc(sizeof(struct ref_list) + len);
57 hashcpy(entry->sha1, sha1);
58 hashclr(entry->peeled);
59 memcpy(entry->name, name, len);
60 entry->flag = flag;
61 entry->next = list;
62 if (new_entry)
63 *new_entry = entry;
64 return entry;
65 }
66
67 /* merge sort the ref list */
68 static struct ref_list *sort_ref_list(struct ref_list *list)
69 {
70 int psize, qsize, last_merge_count, cmp;
71 struct ref_list *p, *q, *l, *e;
72 struct ref_list *new_list = list;
73 int k = 1;
74 int merge_count = 0;
75
76 if (!list)
77 return list;
78
79 do {
80 last_merge_count = merge_count;
81 merge_count = 0;
82
83 psize = 0;
84
85 p = new_list;
86 q = new_list;
87 new_list = NULL;
88 l = NULL;
89
90 while (p) {
91 merge_count++;
92
93 while (psize < k && q->next) {
94 q = q->next;
95 psize++;
96 }
97 qsize = k;
98
99 while ((psize > 0) || (qsize > 0 && q)) {
100 if (qsize == 0 || !q) {
101 e = p;
102 p = p->next;
103 psize--;
104 } else if (psize == 0) {
105 e = q;
106 q = q->next;
107 qsize--;
108 } else {
109 cmp = strcmp(q->name, p->name);
110 if (cmp < 0) {
111 e = q;
112 q = q->next;
113 qsize--;
114 } else if (cmp > 0) {
115 e = p;
116 p = p->next;
117 psize--;
118 } else {
119 if (hashcmp(q->sha1, p->sha1))
120 die("Duplicated ref, and SHA1s don't match: %s",
121 q->name);
122 warning("Duplicated ref: %s", q->name);
123 e = q;
124 q = q->next;
125 qsize--;
126 free(e);
127 e = p;
128 p = p->next;
129 psize--;
130 }
131 }
132
133 e->next = NULL;
134
135 if (l)
136 l->next = e;
137 if (!new_list)
138 new_list = e;
139 l = e;
140 }
141
142 p = q;
143 };
144
145 k = k * 2;
146 } while ((last_merge_count != merge_count) || (last_merge_count != 1));
147
148 return new_list;
149 }
150
151 /*
152 * Future: need to be in "struct repository"
153 * when doing a full libification.
154 */
155 static struct cached_refs {
156 char did_loose;
157 char did_packed;
158 struct ref_list *loose;
159 struct ref_list *packed;
160 } cached_refs, submodule_refs;
161 static struct ref_list *current_ref;
162
163 static struct ref_list *extra_refs;
164
165 static void free_ref_list(struct ref_list *list)
166 {
167 struct ref_list *next;
168 for ( ; list; list = next) {
169 next = list->next;
170 free(list);
171 }
172 }
173
174 static void invalidate_cached_refs(void)
175 {
176 struct cached_refs *ca = &cached_refs;
177
178 if (ca->did_loose && ca->loose)
179 free_ref_list(ca->loose);
180 if (ca->did_packed && ca->packed)
181 free_ref_list(ca->packed);
182 ca->loose = ca->packed = NULL;
183 ca->did_loose = ca->did_packed = 0;
184 }
185
186 static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
187 {
188 struct ref_list *list = NULL;
189 struct ref_list *last = NULL;
190 char refline[PATH_MAX];
191 int flag = REF_ISPACKED;
192
193 while (fgets(refline, sizeof(refline), f)) {
194 unsigned char sha1[20];
195 const char *name;
196 static const char header[] = "# pack-refs with:";
197
198 if (!strncmp(refline, header, sizeof(header)-1)) {
199 const char *traits = refline + sizeof(header) - 1;
200 if (strstr(traits, " peeled "))
201 flag |= REF_KNOWS_PEELED;
202 /* perhaps other traits later as well */
203 continue;
204 }
205
206 name = parse_ref_line(refline, sha1);
207 if (name) {
208 list = add_ref(name, sha1, flag, list, &last);
209 continue;
210 }
211 if (last &&
212 refline[0] == '^' &&
213 strlen(refline) == 42 &&
214 refline[41] == '\n' &&
215 !get_sha1_hex(refline + 1, sha1))
216 hashcpy(last->peeled, sha1);
217 }
218 cached_refs->packed = sort_ref_list(list);
219 }
220
221 void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
222 {
223 extra_refs = add_ref(name, sha1, flag, extra_refs, NULL);
224 }
225
226 void clear_extra_refs(void)
227 {
228 free_ref_list(extra_refs);
229 extra_refs = NULL;
230 }
231
232 static struct ref_list *get_packed_refs(const char *submodule)
233 {
234 const char *packed_refs_file;
235 struct cached_refs *refs;
236
237 if (submodule) {
238 packed_refs_file = git_path_submodule(submodule, "packed-refs");
239 refs = &submodule_refs;
240 free_ref_list(refs->packed);
241 } else {
242 packed_refs_file = git_path("packed-refs");
243 refs = &cached_refs;
244 }
245
246 if (!refs->did_packed || submodule) {
247 FILE *f = fopen(packed_refs_file, "r");
248 refs->packed = NULL;
249 if (f) {
250 read_packed_refs(f, refs);
251 fclose(f);
252 }
253 refs->did_packed = 1;
254 }
255 return refs->packed;
256 }
257
258 static struct ref_list *get_ref_dir(const char *submodule, const char *base,
259 struct ref_list *list)
260 {
261 DIR *dir;
262 const char *path;
263
264 if (submodule)
265 path = git_path_submodule(submodule, "%s", base);
266 else
267 path = git_path("%s", base);
268
269
270 dir = opendir(path);
271
272 if (dir) {
273 struct dirent *de;
274 int baselen = strlen(base);
275 char *ref = xmalloc(baselen + 257);
276
277 memcpy(ref, base, baselen);
278 if (baselen && base[baselen-1] != '/')
279 ref[baselen++] = '/';
280
281 while ((de = readdir(dir)) != NULL) {
282 unsigned char sha1[20];
283 struct stat st;
284 int flag;
285 int namelen;
286 const char *refdir;
287
288 if (de->d_name[0] == '.')
289 continue;
290 namelen = strlen(de->d_name);
291 if (namelen > 255)
292 continue;
293 if (has_extension(de->d_name, ".lock"))
294 continue;
295 memcpy(ref + baselen, de->d_name, namelen+1);
296 refdir = submodule
297 ? git_path_submodule(submodule, "%s", ref)
298 : git_path("%s", ref);
299 if (stat(refdir, &st) < 0)
300 continue;
301 if (S_ISDIR(st.st_mode)) {
302 list = get_ref_dir(submodule, ref, list);
303 continue;
304 }
305 if (submodule) {
306 hashclr(sha1);
307 flag = 0;
308 if (resolve_gitlink_ref(submodule, ref, sha1) < 0) {
309 hashclr(sha1);
310 flag |= REF_BROKEN;
311 }
312 } else
313 if (!resolve_ref(ref, sha1, 1, &flag)) {
314 hashclr(sha1);
315 flag |= REF_BROKEN;
316 }
317 list = add_ref(ref, sha1, flag, list, NULL);
318 }
319 free(ref);
320 closedir(dir);
321 }
322 return sort_ref_list(list);
323 }
324
325 struct warn_if_dangling_data {
326 FILE *fp;
327 const char *refname;
328 const char *msg_fmt;
329 };
330
331 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
332 int flags, void *cb_data)
333 {
334 struct warn_if_dangling_data *d = cb_data;
335 const char *resolves_to;
336 unsigned char junk[20];
337
338 if (!(flags & REF_ISSYMREF))
339 return 0;
340
341 resolves_to = resolve_ref(refname, junk, 0, NULL);
342 if (!resolves_to || strcmp(resolves_to, d->refname))
343 return 0;
344
345 fprintf(d->fp, d->msg_fmt, refname);
346 return 0;
347 }
348
349 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
350 {
351 struct warn_if_dangling_data data;
352
353 data.fp = fp;
354 data.refname = refname;
355 data.msg_fmt = msg_fmt;
356 for_each_rawref(warn_if_dangling_symref, &data);
357 }
358
359 static struct ref_list *get_loose_refs(const char *submodule)
360 {
361 if (submodule) {
362 free_ref_list(submodule_refs.loose);
363 submodule_refs.loose = get_ref_dir(submodule, "refs", NULL);
364 return submodule_refs.loose;
365 }
366
367 if (!cached_refs.did_loose) {
368 cached_refs.loose = get_ref_dir(NULL, "refs", NULL);
369 cached_refs.did_loose = 1;
370 }
371 return cached_refs.loose;
372 }
373
374 /* We allow "recursive" symbolic refs. Only within reason, though */
375 #define MAXDEPTH 5
376 #define MAXREFLEN (1024)
377
378 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
379 {
380 FILE *f;
381 struct cached_refs refs;
382 struct ref_list *ref;
383 int retval;
384
385 strcpy(name + pathlen, "packed-refs");
386 f = fopen(name, "r");
387 if (!f)
388 return -1;
389 read_packed_refs(f, &refs);
390 fclose(f);
391 ref = refs.packed;
392 retval = -1;
393 while (ref) {
394 if (!strcmp(ref->name, refname)) {
395 retval = 0;
396 memcpy(result, ref->sha1, 20);
397 break;
398 }
399 ref = ref->next;
400 }
401 free_ref_list(refs.packed);
402 return retval;
403 }
404
405 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
406 {
407 int fd, len = strlen(refname);
408 char buffer[128], *p;
409
410 if (recursion > MAXDEPTH || len > MAXREFLEN)
411 return -1;
412 memcpy(name + pathlen, refname, len+1);
413 fd = open(name, O_RDONLY);
414 if (fd < 0)
415 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
416
417 len = read(fd, buffer, sizeof(buffer)-1);
418 close(fd);
419 if (len < 0)
420 return -1;
421 while (len && isspace(buffer[len-1]))
422 len--;
423 buffer[len] = 0;
424
425 /* Was it a detached head or an old-fashioned symlink? */
426 if (!get_sha1_hex(buffer, result))
427 return 0;
428
429 /* Symref? */
430 if (strncmp(buffer, "ref:", 4))
431 return -1;
432 p = buffer + 4;
433 while (isspace(*p))
434 p++;
435
436 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
437 }
438
439 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
440 {
441 int len = strlen(path), retval;
442 char *gitdir;
443 const char *tmp;
444
445 while (len && path[len-1] == '/')
446 len--;
447 if (!len)
448 return -1;
449 gitdir = xmalloc(len + MAXREFLEN + 8);
450 memcpy(gitdir, path, len);
451 memcpy(gitdir + len, "/.git", 6);
452 len += 5;
453
454 tmp = read_gitfile(gitdir);
455 if (tmp) {
456 free(gitdir);
457 len = strlen(tmp);
458 gitdir = xmalloc(len + MAXREFLEN + 3);
459 memcpy(gitdir, tmp, len);
460 }
461 gitdir[len] = '/';
462 gitdir[++len] = '\0';
463 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
464 free(gitdir);
465 return retval;
466 }
467
468 /*
469 * Try to read ref from the packed references. On success, set sha1
470 * and return 0; otherwise, return -1.
471 */
472 static int get_packed_ref(const char *ref, unsigned char *sha1)
473 {
474 struct ref_list *list = get_packed_refs(NULL);
475 while (list) {
476 if (!strcmp(ref, list->name)) {
477 hashcpy(sha1, list->sha1);
478 return 0;
479 }
480 list = list->next;
481 }
482 return -1;
483 }
484
485 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
486 {
487 int depth = MAXDEPTH;
488 ssize_t len;
489 char buffer[256];
490 static char ref_buffer[256];
491 char path[PATH_MAX];
492
493 if (flag)
494 *flag = 0;
495
496 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
497 return NULL;
498
499 for (;;) {
500 struct stat st;
501 char *buf;
502 int fd;
503
504 if (--depth < 0)
505 return NULL;
506
507 git_snpath(path, sizeof(path), "%s", ref);
508
509 if (lstat(path, &st) < 0) {
510 if (errno != ENOENT)
511 return NULL;
512 /*
513 * The loose reference file does not exist;
514 * check for a packed reference.
515 */
516 if (!get_packed_ref(ref, sha1)) {
517 if (flag)
518 *flag |= REF_ISPACKED;
519 return ref;
520 }
521 /* The reference is not a packed reference, either. */
522 if (reading) {
523 return NULL;
524 } else {
525 hashclr(sha1);
526 return ref;
527 }
528 }
529
530 /* Follow "normalized" - ie "refs/.." symlinks by hand */
531 if (S_ISLNK(st.st_mode)) {
532 len = readlink(path, buffer, sizeof(buffer)-1);
533 if (len < 0)
534 return NULL;
535 buffer[len] = 0;
536 if (!prefixcmp(buffer, "refs/") &&
537 !check_refname_format(buffer, 0)) {
538 strcpy(ref_buffer, buffer);
539 ref = ref_buffer;
540 if (flag)
541 *flag |= REF_ISSYMREF;
542 continue;
543 }
544 }
545
546 /* Is it a directory? */
547 if (S_ISDIR(st.st_mode)) {
548 errno = EISDIR;
549 return NULL;
550 }
551
552 /*
553 * Anything else, just open it and try to use it as
554 * a ref
555 */
556 fd = open(path, O_RDONLY);
557 if (fd < 0)
558 return NULL;
559 len = read_in_full(fd, buffer, sizeof(buffer)-1);
560 close(fd);
561 if (len < 0)
562 return NULL;
563 while (len && isspace(buffer[len-1]))
564 len--;
565 buffer[len] = '\0';
566
567 /*
568 * Is it a symbolic ref?
569 */
570 if (prefixcmp(buffer, "ref:"))
571 break;
572 buf = buffer + 4;
573 while (isspace(*buf))
574 buf++;
575 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
576 warning("symbolic reference in %s is formatted incorrectly",
577 path);
578 return NULL;
579 }
580 ref = strcpy(ref_buffer, buf);
581 if (flag)
582 *flag |= REF_ISSYMREF;
583 }
584 /* Please note that FETCH_HEAD has a second line containing other data. */
585 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
586 warning("reference in %s is formatted incorrectly", path);
587 return NULL;
588 }
589 return ref;
590 }
591
592 /* The argument to filter_refs */
593 struct ref_filter {
594 const char *pattern;
595 each_ref_fn *fn;
596 void *cb_data;
597 };
598
599 int read_ref(const char *ref, unsigned char *sha1)
600 {
601 if (resolve_ref(ref, sha1, 1, NULL))
602 return 0;
603 return -1;
604 }
605
606 #define DO_FOR_EACH_INCLUDE_BROKEN 01
607 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
608 int flags, void *cb_data, struct ref_list *entry)
609 {
610 if (prefixcmp(entry->name, base))
611 return 0;
612
613 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
614 if (entry->flag & REF_BROKEN)
615 return 0; /* ignore dangling symref */
616 if (!has_sha1_file(entry->sha1)) {
617 error("%s does not point to a valid object!", entry->name);
618 return 0;
619 }
620 }
621 current_ref = entry;
622 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
623 }
624
625 static int filter_refs(const char *ref, const unsigned char *sha, int flags,
626 void *data)
627 {
628 struct ref_filter *filter = (struct ref_filter *)data;
629 if (fnmatch(filter->pattern, ref, 0))
630 return 0;
631 return filter->fn(ref, sha, flags, filter->cb_data);
632 }
633
634 int peel_ref(const char *ref, unsigned char *sha1)
635 {
636 int flag;
637 unsigned char base[20];
638 struct object *o;
639
640 if (current_ref && (current_ref->name == ref
641 || !strcmp(current_ref->name, ref))) {
642 if (current_ref->flag & REF_KNOWS_PEELED) {
643 hashcpy(sha1, current_ref->peeled);
644 return 0;
645 }
646 hashcpy(base, current_ref->sha1);
647 goto fallback;
648 }
649
650 if (!resolve_ref(ref, base, 1, &flag))
651 return -1;
652
653 if ((flag & REF_ISPACKED)) {
654 struct ref_list *list = get_packed_refs(NULL);
655
656 while (list) {
657 if (!strcmp(list->name, ref)) {
658 if (list->flag & REF_KNOWS_PEELED) {
659 hashcpy(sha1, list->peeled);
660 return 0;
661 }
662 /* older pack-refs did not leave peeled ones */
663 break;
664 }
665 list = list->next;
666 }
667 }
668
669 fallback:
670 o = parse_object(base);
671 if (o && o->type == OBJ_TAG) {
672 o = deref_tag(o, ref, 0);
673 if (o) {
674 hashcpy(sha1, o->sha1);
675 return 0;
676 }
677 }
678 return -1;
679 }
680
681 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
682 int trim, int flags, void *cb_data)
683 {
684 int retval = 0;
685 struct ref_list *packed = get_packed_refs(submodule);
686 struct ref_list *loose = get_loose_refs(submodule);
687
688 struct ref_list *extra;
689
690 for (extra = extra_refs; extra; extra = extra->next)
691 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
692
693 while (packed && loose) {
694 struct ref_list *entry;
695 int cmp = strcmp(packed->name, loose->name);
696 if (!cmp) {
697 packed = packed->next;
698 continue;
699 }
700 if (cmp > 0) {
701 entry = loose;
702 loose = loose->next;
703 } else {
704 entry = packed;
705 packed = packed->next;
706 }
707 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
708 if (retval)
709 goto end_each;
710 }
711
712 for (packed = packed ? packed : loose; packed; packed = packed->next) {
713 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
714 if (retval)
715 goto end_each;
716 }
717
718 end_each:
719 current_ref = NULL;
720 return retval;
721 }
722
723
724 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
725 {
726 unsigned char sha1[20];
727 int flag;
728
729 if (submodule) {
730 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
731 return fn("HEAD", sha1, 0, cb_data);
732
733 return 0;
734 }
735
736 if (resolve_ref("HEAD", sha1, 1, &flag))
737 return fn("HEAD", sha1, flag, cb_data);
738
739 return 0;
740 }
741
742 int head_ref(each_ref_fn fn, void *cb_data)
743 {
744 return do_head_ref(NULL, fn, cb_data);
745 }
746
747 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
748 {
749 return do_head_ref(submodule, fn, cb_data);
750 }
751
752 int for_each_ref(each_ref_fn fn, void *cb_data)
753 {
754 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
755 }
756
757 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
758 {
759 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
760 }
761
762 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
763 {
764 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
765 }
766
767 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
768 each_ref_fn fn, void *cb_data)
769 {
770 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
771 }
772
773 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
774 {
775 return for_each_ref_in("refs/tags/", fn, cb_data);
776 }
777
778 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
779 {
780 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
781 }
782
783 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
784 {
785 return for_each_ref_in("refs/heads/", fn, cb_data);
786 }
787
788 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
789 {
790 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
791 }
792
793 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
794 {
795 return for_each_ref_in("refs/remotes/", fn, cb_data);
796 }
797
798 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
799 {
800 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
801 }
802
803 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
804 {
805 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
806 }
807
808 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
809 {
810 struct strbuf buf = STRBUF_INIT;
811 int ret = 0;
812 unsigned char sha1[20];
813 int flag;
814
815 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
816 if (resolve_ref(buf.buf, sha1, 1, &flag))
817 ret = fn(buf.buf, sha1, flag, cb_data);
818 strbuf_release(&buf);
819
820 return ret;
821 }
822
823 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
824 {
825 struct strbuf buf = STRBUF_INIT;
826 int ret;
827 strbuf_addf(&buf, "%srefs/", get_git_namespace());
828 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
829 strbuf_release(&buf);
830 return ret;
831 }
832
833 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
834 const char *prefix, void *cb_data)
835 {
836 struct strbuf real_pattern = STRBUF_INIT;
837 struct ref_filter filter;
838 int ret;
839
840 if (!prefix && prefixcmp(pattern, "refs/"))
841 strbuf_addstr(&real_pattern, "refs/");
842 else if (prefix)
843 strbuf_addstr(&real_pattern, prefix);
844 strbuf_addstr(&real_pattern, pattern);
845
846 if (!has_glob_specials(pattern)) {
847 /* Append implied '/' '*' if not present. */
848 if (real_pattern.buf[real_pattern.len - 1] != '/')
849 strbuf_addch(&real_pattern, '/');
850 /* No need to check for '*', there is none. */
851 strbuf_addch(&real_pattern, '*');
852 }
853
854 filter.pattern = real_pattern.buf;
855 filter.fn = fn;
856 filter.cb_data = cb_data;
857 ret = for_each_ref(filter_refs, &filter);
858
859 strbuf_release(&real_pattern);
860 return ret;
861 }
862
863 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
864 {
865 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
866 }
867
868 int for_each_rawref(each_ref_fn fn, void *cb_data)
869 {
870 return do_for_each_ref(NULL, "", fn, 0,
871 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
872 }
873
874 /*
875 * Make sure "ref" is something reasonable to have under ".git/refs/";
876 * We do not like it if:
877 *
878 * - any path component of it begins with ".", or
879 * - it has double dots "..", or
880 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
881 * - it ends with a "/".
882 * - it ends with ".lock"
883 * - it contains a "\" (backslash)
884 */
885
886 /* Return true iff ch is not allowed in reference names. */
887 static inline int bad_ref_char(int ch)
888 {
889 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
890 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
891 return 1;
892 /* 2.13 Pattern Matching Notation */
893 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
894 return 1;
895 return 0;
896 }
897
898 /*
899 * Try to read one refname component from the front of ref. Return
900 * the length of the component found, or -1 if the component is not
901 * legal.
902 */
903 static int check_refname_component(const char *ref)
904 {
905 const char *cp;
906 char last = '\0';
907
908 for (cp = ref; ; cp++) {
909 char ch = *cp;
910 if (ch == '\0' || ch == '/')
911 break;
912 if (bad_ref_char(ch))
913 return -1; /* Illegal character in refname. */
914 if (last == '.' && ch == '.')
915 return -1; /* Refname contains "..". */
916 if (last == '@' && ch == '{')
917 return -1; /* Refname contains "@{". */
918 last = ch;
919 }
920 if (cp == ref)
921 return -1; /* Component has zero length. */
922 if (ref[0] == '.')
923 return -1; /* Component starts with '.'. */
924 if (cp - ref >= 5 && !memcmp(cp - 5, ".lock", 5))
925 return -1; /* Refname ends with ".lock". */
926 return cp - ref;
927 }
928
929 int check_refname_format(const char *ref, int flags)
930 {
931 int component_len, component_count = 0;
932
933 while (1) {
934 /* We are at the start of a path component. */
935 component_len = check_refname_component(ref);
936 if (component_len < 0) {
937 if ((flags & REFNAME_REFSPEC_PATTERN) &&
938 ref[0] == '*' &&
939 (ref[1] == '\0' || ref[1] == '/')) {
940 /* Accept one wildcard as a full refname component. */
941 flags &= ~REFNAME_REFSPEC_PATTERN;
942 component_len = 1;
943 } else {
944 return -1;
945 }
946 }
947 component_count++;
948 if (ref[component_len] == '\0')
949 break;
950 /* Skip to next component. */
951 ref += component_len + 1;
952 }
953
954 if (ref[component_len - 1] == '.')
955 return -1; /* Refname ends with '.'. */
956 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
957 return -1; /* Refname has only one component. */
958 return 0;
959 }
960
961 const char *prettify_refname(const char *name)
962 {
963 return name + (
964 !prefixcmp(name, "refs/heads/") ? 11 :
965 !prefixcmp(name, "refs/tags/") ? 10 :
966 !prefixcmp(name, "refs/remotes/") ? 13 :
967 0);
968 }
969
970 const char *ref_rev_parse_rules[] = {
971 "%.*s",
972 "refs/%.*s",
973 "refs/tags/%.*s",
974 "refs/heads/%.*s",
975 "refs/remotes/%.*s",
976 "refs/remotes/%.*s/HEAD",
977 NULL
978 };
979
980 const char *ref_fetch_rules[] = {
981 "%.*s",
982 "refs/%.*s",
983 "refs/heads/%.*s",
984 NULL
985 };
986
987 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
988 {
989 const char **p;
990 const int abbrev_name_len = strlen(abbrev_name);
991
992 for (p = rules; *p; p++) {
993 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
994 return 1;
995 }
996 }
997
998 return 0;
999 }
1000
1001 static struct ref_lock *verify_lock(struct ref_lock *lock,
1002 const unsigned char *old_sha1, int mustexist)
1003 {
1004 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
1005 error("Can't verify ref %s", lock->ref_name);
1006 unlock_ref(lock);
1007 return NULL;
1008 }
1009 if (hashcmp(lock->old_sha1, old_sha1)) {
1010 error("Ref %s is at %s but expected %s", lock->ref_name,
1011 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1012 unlock_ref(lock);
1013 return NULL;
1014 }
1015 return lock;
1016 }
1017
1018 static int remove_empty_directories(const char *file)
1019 {
1020 /* we want to create a file but there is a directory there;
1021 * if that is an empty directory (or a directory that contains
1022 * only empty directories), remove them.
1023 */
1024 struct strbuf path;
1025 int result;
1026
1027 strbuf_init(&path, 20);
1028 strbuf_addstr(&path, file);
1029
1030 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1031
1032 strbuf_release(&path);
1033
1034 return result;
1035 }
1036
1037 static int is_refname_available(const char *ref, const char *oldref,
1038 struct ref_list *list, int quiet)
1039 {
1040 int namlen = strlen(ref); /* e.g. 'foo/bar' */
1041 while (list) {
1042 /* list->name could be 'foo' or 'foo/bar/baz' */
1043 if (!oldref || strcmp(oldref, list->name)) {
1044 int len = strlen(list->name);
1045 int cmplen = (namlen < len) ? namlen : len;
1046 const char *lead = (namlen < len) ? list->name : ref;
1047 if (!strncmp(ref, list->name, cmplen) &&
1048 lead[cmplen] == '/') {
1049 if (!quiet)
1050 error("'%s' exists; cannot create '%s'",
1051 list->name, ref);
1052 return 0;
1053 }
1054 }
1055 list = list->next;
1056 }
1057 return 1;
1058 }
1059
1060 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
1061 {
1062 char *ref_file;
1063 const char *orig_ref = ref;
1064 struct ref_lock *lock;
1065 int last_errno = 0;
1066 int type, lflags;
1067 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1068 int missing = 0;
1069
1070 lock = xcalloc(1, sizeof(struct ref_lock));
1071 lock->lock_fd = -1;
1072
1073 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
1074 if (!ref && errno == EISDIR) {
1075 /* we are trying to lock foo but we used to
1076 * have foo/bar which now does not exist;
1077 * it is normal for the empty directory 'foo'
1078 * to remain.
1079 */
1080 ref_file = git_path("%s", orig_ref);
1081 if (remove_empty_directories(ref_file)) {
1082 last_errno = errno;
1083 error("there are still refs under '%s'", orig_ref);
1084 goto error_return;
1085 }
1086 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
1087 }
1088 if (type_p)
1089 *type_p = type;
1090 if (!ref) {
1091 last_errno = errno;
1092 error("unable to resolve reference %s: %s",
1093 orig_ref, strerror(errno));
1094 goto error_return;
1095 }
1096 missing = is_null_sha1(lock->old_sha1);
1097 /* When the ref did not exist and we are creating it,
1098 * make sure there is no existing ref that is packed
1099 * whose name begins with our refname, nor a ref whose
1100 * name is a proper prefix of our refname.
1101 */
1102 if (missing &&
1103 !is_refname_available(ref, NULL, get_packed_refs(NULL), 0)) {
1104 last_errno = ENOTDIR;
1105 goto error_return;
1106 }
1107
1108 lock->lk = xcalloc(1, sizeof(struct lock_file));
1109
1110 lflags = LOCK_DIE_ON_ERROR;
1111 if (flags & REF_NODEREF) {
1112 ref = orig_ref;
1113 lflags |= LOCK_NODEREF;
1114 }
1115 lock->ref_name = xstrdup(ref);
1116 lock->orig_ref_name = xstrdup(orig_ref);
1117 ref_file = git_path("%s", ref);
1118 if (missing)
1119 lock->force_write = 1;
1120 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1121 lock->force_write = 1;
1122
1123 if (safe_create_leading_directories(ref_file)) {
1124 last_errno = errno;
1125 error("unable to create directory for %s", ref_file);
1126 goto error_return;
1127 }
1128
1129 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1130 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1131
1132 error_return:
1133 unlock_ref(lock);
1134 errno = last_errno;
1135 return NULL;
1136 }
1137
1138 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
1139 {
1140 char refpath[PATH_MAX];
1141 if (check_refname_format(ref, 0))
1142 return NULL;
1143 strcpy(refpath, mkpath("refs/%s", ref));
1144 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1145 }
1146
1147 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
1148 {
1149 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
1150 return NULL;
1151 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1152 }
1153
1154 static struct lock_file packlock;
1155
1156 static int repack_without_ref(const char *refname)
1157 {
1158 struct ref_list *list, *packed_ref_list;
1159 int fd;
1160 int found = 0;
1161
1162 packed_ref_list = get_packed_refs(NULL);
1163 for (list = packed_ref_list; list; list = list->next) {
1164 if (!strcmp(refname, list->name)) {
1165 found = 1;
1166 break;
1167 }
1168 }
1169 if (!found)
1170 return 0;
1171 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1172 if (fd < 0) {
1173 unable_to_lock_error(git_path("packed-refs"), errno);
1174 return error("cannot delete '%s' from packed refs", refname);
1175 }
1176
1177 for (list = packed_ref_list; list; list = list->next) {
1178 char line[PATH_MAX + 100];
1179 int len;
1180
1181 if (!strcmp(refname, list->name))
1182 continue;
1183 len = snprintf(line, sizeof(line), "%s %s\n",
1184 sha1_to_hex(list->sha1), list->name);
1185 /* this should not happen but just being defensive */
1186 if (len > sizeof(line))
1187 die("too long a refname '%s'", list->name);
1188 write_or_die(fd, line, len);
1189 }
1190 return commit_lock_file(&packlock);
1191 }
1192
1193 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1194 {
1195 struct ref_lock *lock;
1196 int err, i = 0, ret = 0, flag = 0;
1197
1198 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1199 if (!lock)
1200 return 1;
1201 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1202 /* loose */
1203 const char *path;
1204
1205 if (!(delopt & REF_NODEREF)) {
1206 i = strlen(lock->lk->filename) - 5; /* .lock */
1207 lock->lk->filename[i] = 0;
1208 path = lock->lk->filename;
1209 } else {
1210 path = git_path("%s", refname);
1211 }
1212 err = unlink_or_warn(path);
1213 if (err && errno != ENOENT)
1214 ret = 1;
1215
1216 if (!(delopt & REF_NODEREF))
1217 lock->lk->filename[i] = '.';
1218 }
1219 /* removing the loose one could have resurrected an earlier
1220 * packed one. Also, if it was not loose we need to repack
1221 * without it.
1222 */
1223 ret |= repack_without_ref(refname);
1224
1225 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1226 invalidate_cached_refs();
1227 unlock_ref(lock);
1228 return ret;
1229 }
1230
1231 /*
1232 * People using contrib's git-new-workdir have .git/logs/refs ->
1233 * /some/other/path/.git/logs/refs, and that may live on another device.
1234 *
1235 * IOW, to avoid cross device rename errors, the temporary renamed log must
1236 * live into logs/refs.
1237 */
1238 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1239
1240 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1241 {
1242 static const char renamed_ref[] = "RENAMED-REF";
1243 unsigned char sha1[20], orig_sha1[20];
1244 int flag = 0, logmoved = 0;
1245 struct ref_lock *lock;
1246 struct stat loginfo;
1247 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1248 const char *symref = NULL;
1249
1250 if (log && S_ISLNK(loginfo.st_mode))
1251 return error("reflog for %s is a symlink", oldref);
1252
1253 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1254 if (flag & REF_ISSYMREF)
1255 return error("refname %s is a symbolic ref, renaming it is not supported",
1256 oldref);
1257 if (!symref)
1258 return error("refname %s not found", oldref);
1259
1260 if (!is_refname_available(newref, oldref, get_packed_refs(NULL), 0))
1261 return 1;
1262
1263 if (!is_refname_available(newref, oldref, get_loose_refs(NULL), 0))
1264 return 1;
1265
1266 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
1267 if (!lock)
1268 return error("unable to lock %s", renamed_ref);
1269 lock->force_write = 1;
1270 if (write_ref_sha1(lock, orig_sha1, logmsg))
1271 return error("unable to save current sha1 in %s", renamed_ref);
1272
1273 if (log && rename(git_path("logs/%s", oldref), git_path(TMP_RENAMED_LOG)))
1274 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1275 oldref, strerror(errno));
1276
1277 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1278 error("unable to delete old %s", oldref);
1279 goto rollback;
1280 }
1281
1282 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1283 if (errno==EISDIR) {
1284 if (remove_empty_directories(git_path("%s", newref))) {
1285 error("Directory not empty: %s", newref);
1286 goto rollback;
1287 }
1288 } else {
1289 error("unable to delete existing %s", newref);
1290 goto rollback;
1291 }
1292 }
1293
1294 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1295 error("unable to create directory for %s", newref);
1296 goto rollback;
1297 }
1298
1299 retry:
1300 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newref))) {
1301 if (errno==EISDIR || errno==ENOTDIR) {
1302 /*
1303 * rename(a, b) when b is an existing
1304 * directory ought to result in ISDIR, but
1305 * Solaris 5.8 gives ENOTDIR. Sheesh.
1306 */
1307 if (remove_empty_directories(git_path("logs/%s", newref))) {
1308 error("Directory not empty: logs/%s", newref);
1309 goto rollback;
1310 }
1311 goto retry;
1312 } else {
1313 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1314 newref, strerror(errno));
1315 goto rollback;
1316 }
1317 }
1318 logmoved = log;
1319
1320 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1321 if (!lock) {
1322 error("unable to lock %s for update", newref);
1323 goto rollback;
1324 }
1325 lock->force_write = 1;
1326 hashcpy(lock->old_sha1, orig_sha1);
1327 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1328 error("unable to write current sha1 into %s", newref);
1329 goto rollback;
1330 }
1331
1332 return 0;
1333
1334 rollback:
1335 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1336 if (!lock) {
1337 error("unable to lock %s for rollback", oldref);
1338 goto rollbacklog;
1339 }
1340
1341 lock->force_write = 1;
1342 flag = log_all_ref_updates;
1343 log_all_ref_updates = 0;
1344 if (write_ref_sha1(lock, orig_sha1, NULL))
1345 error("unable to write current sha1 into %s", oldref);
1346 log_all_ref_updates = flag;
1347
1348 rollbacklog:
1349 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1350 error("unable to restore logfile %s from %s: %s",
1351 oldref, newref, strerror(errno));
1352 if (!logmoved && log &&
1353 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldref)))
1354 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1355 oldref, strerror(errno));
1356
1357 return 1;
1358 }
1359
1360 int close_ref(struct ref_lock *lock)
1361 {
1362 if (close_lock_file(lock->lk))
1363 return -1;
1364 lock->lock_fd = -1;
1365 return 0;
1366 }
1367
1368 int commit_ref(struct ref_lock *lock)
1369 {
1370 if (commit_lock_file(lock->lk))
1371 return -1;
1372 lock->lock_fd = -1;
1373 return 0;
1374 }
1375
1376 void unlock_ref(struct ref_lock *lock)
1377 {
1378 /* Do not free lock->lk -- atexit() still looks at them */
1379 if (lock->lk)
1380 rollback_lock_file(lock->lk);
1381 free(lock->ref_name);
1382 free(lock->orig_ref_name);
1383 free(lock);
1384 }
1385
1386 /*
1387 * copy the reflog message msg to buf, which has been allocated sufficiently
1388 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1389 * because reflog file is one line per entry.
1390 */
1391 static int copy_msg(char *buf, const char *msg)
1392 {
1393 char *cp = buf;
1394 char c;
1395 int wasspace = 1;
1396
1397 *cp++ = '\t';
1398 while ((c = *msg++)) {
1399 if (wasspace && isspace(c))
1400 continue;
1401 wasspace = isspace(c);
1402 if (wasspace)
1403 c = ' ';
1404 *cp++ = c;
1405 }
1406 while (buf < cp && isspace(cp[-1]))
1407 cp--;
1408 *cp++ = '\n';
1409 return cp - buf;
1410 }
1411
1412 int log_ref_setup(const char *ref_name, char *logfile, int bufsize)
1413 {
1414 int logfd, oflags = O_APPEND | O_WRONLY;
1415
1416 git_snpath(logfile, bufsize, "logs/%s", ref_name);
1417 if (log_all_ref_updates &&
1418 (!prefixcmp(ref_name, "refs/heads/") ||
1419 !prefixcmp(ref_name, "refs/remotes/") ||
1420 !prefixcmp(ref_name, "refs/notes/") ||
1421 !strcmp(ref_name, "HEAD"))) {
1422 if (safe_create_leading_directories(logfile) < 0)
1423 return error("unable to create directory for %s",
1424 logfile);
1425 oflags |= O_CREAT;
1426 }
1427
1428 logfd = open(logfile, oflags, 0666);
1429 if (logfd < 0) {
1430 if (!(oflags & O_CREAT) && errno == ENOENT)
1431 return 0;
1432
1433 if ((oflags & O_CREAT) && errno == EISDIR) {
1434 if (remove_empty_directories(logfile)) {
1435 return error("There are still logs under '%s'",
1436 logfile);
1437 }
1438 logfd = open(logfile, oflags, 0666);
1439 }
1440
1441 if (logfd < 0)
1442 return error("Unable to append to %s: %s",
1443 logfile, strerror(errno));
1444 }
1445
1446 adjust_shared_perm(logfile);
1447 close(logfd);
1448 return 0;
1449 }
1450
1451 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1452 const unsigned char *new_sha1, const char *msg)
1453 {
1454 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1455 unsigned maxlen, len;
1456 int msglen;
1457 char log_file[PATH_MAX];
1458 char *logrec;
1459 const char *committer;
1460
1461 if (log_all_ref_updates < 0)
1462 log_all_ref_updates = !is_bare_repository();
1463
1464 result = log_ref_setup(ref_name, log_file, sizeof(log_file));
1465 if (result)
1466 return result;
1467
1468 logfd = open(log_file, oflags);
1469 if (logfd < 0)
1470 return 0;
1471 msglen = msg ? strlen(msg) : 0;
1472 committer = git_committer_info(0);
1473 maxlen = strlen(committer) + msglen + 100;
1474 logrec = xmalloc(maxlen);
1475 len = sprintf(logrec, "%s %s %s\n",
1476 sha1_to_hex(old_sha1),
1477 sha1_to_hex(new_sha1),
1478 committer);
1479 if (msglen)
1480 len += copy_msg(logrec + len - 1, msg) - 1;
1481 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1482 free(logrec);
1483 if (close(logfd) != 0 || written != len)
1484 return error("Unable to append to %s", log_file);
1485 return 0;
1486 }
1487
1488 static int is_branch(const char *refname)
1489 {
1490 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1491 }
1492
1493 int write_ref_sha1(struct ref_lock *lock,
1494 const unsigned char *sha1, const char *logmsg)
1495 {
1496 static char term = '\n';
1497 struct object *o;
1498
1499 if (!lock)
1500 return -1;
1501 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1502 unlock_ref(lock);
1503 return 0;
1504 }
1505 o = parse_object(sha1);
1506 if (!o) {
1507 error("Trying to write ref %s with nonexistent object %s",
1508 lock->ref_name, sha1_to_hex(sha1));
1509 unlock_ref(lock);
1510 return -1;
1511 }
1512 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1513 error("Trying to write non-commit object %s to branch %s",
1514 sha1_to_hex(sha1), lock->ref_name);
1515 unlock_ref(lock);
1516 return -1;
1517 }
1518 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1519 write_in_full(lock->lock_fd, &term, 1) != 1
1520 || close_ref(lock) < 0) {
1521 error("Couldn't write %s", lock->lk->filename);
1522 unlock_ref(lock);
1523 return -1;
1524 }
1525 invalidate_cached_refs();
1526 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1527 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1528 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1529 unlock_ref(lock);
1530 return -1;
1531 }
1532 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1533 /*
1534 * Special hack: If a branch is updated directly and HEAD
1535 * points to it (may happen on the remote side of a push
1536 * for example) then logically the HEAD reflog should be
1537 * updated too.
1538 * A generic solution implies reverse symref information,
1539 * but finding all symrefs pointing to the given branch
1540 * would be rather costly for this rare event (the direct
1541 * update of a branch) to be worth it. So let's cheat and
1542 * check with HEAD only which should cover 99% of all usage
1543 * scenarios (even 100% of the default ones).
1544 */
1545 unsigned char head_sha1[20];
1546 int head_flag;
1547 const char *head_ref;
1548 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1549 if (head_ref && (head_flag & REF_ISSYMREF) &&
1550 !strcmp(head_ref, lock->ref_name))
1551 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1552 }
1553 if (commit_ref(lock)) {
1554 error("Couldn't set %s", lock->ref_name);
1555 unlock_ref(lock);
1556 return -1;
1557 }
1558 unlock_ref(lock);
1559 return 0;
1560 }
1561
1562 int create_symref(const char *ref_target, const char *refs_heads_master,
1563 const char *logmsg)
1564 {
1565 const char *lockpath;
1566 char ref[1000];
1567 int fd, len, written;
1568 char *git_HEAD = git_pathdup("%s", ref_target);
1569 unsigned char old_sha1[20], new_sha1[20];
1570
1571 if (logmsg && read_ref(ref_target, old_sha1))
1572 hashclr(old_sha1);
1573
1574 if (safe_create_leading_directories(git_HEAD) < 0)
1575 return error("unable to create directory for %s", git_HEAD);
1576
1577 #ifndef NO_SYMLINK_HEAD
1578 if (prefer_symlink_refs) {
1579 unlink(git_HEAD);
1580 if (!symlink(refs_heads_master, git_HEAD))
1581 goto done;
1582 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1583 }
1584 #endif
1585
1586 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1587 if (sizeof(ref) <= len) {
1588 error("refname too long: %s", refs_heads_master);
1589 goto error_free_return;
1590 }
1591 lockpath = mkpath("%s.lock", git_HEAD);
1592 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1593 if (fd < 0) {
1594 error("Unable to open %s for writing", lockpath);
1595 goto error_free_return;
1596 }
1597 written = write_in_full(fd, ref, len);
1598 if (close(fd) != 0 || written != len) {
1599 error("Unable to write to %s", lockpath);
1600 goto error_unlink_return;
1601 }
1602 if (rename(lockpath, git_HEAD) < 0) {
1603 error("Unable to create %s", git_HEAD);
1604 goto error_unlink_return;
1605 }
1606 if (adjust_shared_perm(git_HEAD)) {
1607 error("Unable to fix permissions on %s", lockpath);
1608 error_unlink_return:
1609 unlink_or_warn(lockpath);
1610 error_free_return:
1611 free(git_HEAD);
1612 return -1;
1613 }
1614
1615 #ifndef NO_SYMLINK_HEAD
1616 done:
1617 #endif
1618 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1619 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1620
1621 free(git_HEAD);
1622 return 0;
1623 }
1624
1625 static char *ref_msg(const char *line, const char *endp)
1626 {
1627 const char *ep;
1628 line += 82;
1629 ep = memchr(line, '\n', endp - line);
1630 if (!ep)
1631 ep = endp;
1632 return xmemdupz(line, ep - line);
1633 }
1634
1635 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)
1636 {
1637 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1638 char *tz_c;
1639 int logfd, tz, reccnt = 0;
1640 struct stat st;
1641 unsigned long date;
1642 unsigned char logged_sha1[20];
1643 void *log_mapped;
1644 size_t mapsz;
1645
1646 logfile = git_path("logs/%s", ref);
1647 logfd = open(logfile, O_RDONLY, 0);
1648 if (logfd < 0)
1649 die_errno("Unable to read log '%s'", logfile);
1650 fstat(logfd, &st);
1651 if (!st.st_size)
1652 die("Log %s is empty.", logfile);
1653 mapsz = xsize_t(st.st_size);
1654 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1655 logdata = log_mapped;
1656 close(logfd);
1657
1658 lastrec = NULL;
1659 rec = logend = logdata + st.st_size;
1660 while (logdata < rec) {
1661 reccnt++;
1662 if (logdata < rec && *(rec-1) == '\n')
1663 rec--;
1664 lastgt = NULL;
1665 while (logdata < rec && *(rec-1) != '\n') {
1666 rec--;
1667 if (*rec == '>')
1668 lastgt = rec;
1669 }
1670 if (!lastgt)
1671 die("Log %s is corrupt.", logfile);
1672 date = strtoul(lastgt + 1, &tz_c, 10);
1673 if (date <= at_time || cnt == 0) {
1674 tz = strtoul(tz_c, NULL, 10);
1675 if (msg)
1676 *msg = ref_msg(rec, logend);
1677 if (cutoff_time)
1678 *cutoff_time = date;
1679 if (cutoff_tz)
1680 *cutoff_tz = tz;
1681 if (cutoff_cnt)
1682 *cutoff_cnt = reccnt - 1;
1683 if (lastrec) {
1684 if (get_sha1_hex(lastrec, logged_sha1))
1685 die("Log %s is corrupt.", logfile);
1686 if (get_sha1_hex(rec + 41, sha1))
1687 die("Log %s is corrupt.", logfile);
1688 if (hashcmp(logged_sha1, sha1)) {
1689 warning("Log %s has gap after %s.",
1690 logfile, show_date(date, tz, DATE_RFC2822));
1691 }
1692 }
1693 else if (date == at_time) {
1694 if (get_sha1_hex(rec + 41, sha1))
1695 die("Log %s is corrupt.", logfile);
1696 }
1697 else {
1698 if (get_sha1_hex(rec + 41, logged_sha1))
1699 die("Log %s is corrupt.", logfile);
1700 if (hashcmp(logged_sha1, sha1)) {
1701 warning("Log %s unexpectedly ended on %s.",
1702 logfile, show_date(date, tz, DATE_RFC2822));
1703 }
1704 }
1705 munmap(log_mapped, mapsz);
1706 return 0;
1707 }
1708 lastrec = rec;
1709 if (cnt > 0)
1710 cnt--;
1711 }
1712
1713 rec = logdata;
1714 while (rec < logend && *rec != '>' && *rec != '\n')
1715 rec++;
1716 if (rec == logend || *rec == '\n')
1717 die("Log %s is corrupt.", logfile);
1718 date = strtoul(rec + 1, &tz_c, 10);
1719 tz = strtoul(tz_c, NULL, 10);
1720 if (get_sha1_hex(logdata, sha1))
1721 die("Log %s is corrupt.", logfile);
1722 if (is_null_sha1(sha1)) {
1723 if (get_sha1_hex(logdata + 41, sha1))
1724 die("Log %s is corrupt.", logfile);
1725 }
1726 if (msg)
1727 *msg = ref_msg(logdata, logend);
1728 munmap(log_mapped, mapsz);
1729
1730 if (cutoff_time)
1731 *cutoff_time = date;
1732 if (cutoff_tz)
1733 *cutoff_tz = tz;
1734 if (cutoff_cnt)
1735 *cutoff_cnt = reccnt;
1736 return 1;
1737 }
1738
1739 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1740 {
1741 const char *logfile;
1742 FILE *logfp;
1743 struct strbuf sb = STRBUF_INIT;
1744 int ret = 0;
1745
1746 logfile = git_path("logs/%s", ref);
1747 logfp = fopen(logfile, "r");
1748 if (!logfp)
1749 return -1;
1750
1751 if (ofs) {
1752 struct stat statbuf;
1753 if (fstat(fileno(logfp), &statbuf) ||
1754 statbuf.st_size < ofs ||
1755 fseek(logfp, -ofs, SEEK_END) ||
1756 strbuf_getwholeline(&sb, logfp, '\n')) {
1757 fclose(logfp);
1758 strbuf_release(&sb);
1759 return -1;
1760 }
1761 }
1762
1763 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1764 unsigned char osha1[20], nsha1[20];
1765 char *email_end, *message;
1766 unsigned long timestamp;
1767 int tz;
1768
1769 /* old SP new SP name <email> SP time TAB msg LF */
1770 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1771 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1772 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1773 !(email_end = strchr(sb.buf + 82, '>')) ||
1774 email_end[1] != ' ' ||
1775 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1776 !message || message[0] != ' ' ||
1777 (message[1] != '+' && message[1] != '-') ||
1778 !isdigit(message[2]) || !isdigit(message[3]) ||
1779 !isdigit(message[4]) || !isdigit(message[5]))
1780 continue; /* corrupt? */
1781 email_end[1] = '\0';
1782 tz = strtol(message + 1, NULL, 10);
1783 if (message[6] != '\t')
1784 message += 6;
1785 else
1786 message += 7;
1787 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1788 cb_data);
1789 if (ret)
1790 break;
1791 }
1792 fclose(logfp);
1793 strbuf_release(&sb);
1794 return ret;
1795 }
1796
1797 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1798 {
1799 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1800 }
1801
1802 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1803 {
1804 DIR *dir = opendir(git_path("logs/%s", base));
1805 int retval = 0;
1806
1807 if (dir) {
1808 struct dirent *de;
1809 int baselen = strlen(base);
1810 char *log = xmalloc(baselen + 257);
1811
1812 memcpy(log, base, baselen);
1813 if (baselen && base[baselen-1] != '/')
1814 log[baselen++] = '/';
1815
1816 while ((de = readdir(dir)) != NULL) {
1817 struct stat st;
1818 int namelen;
1819
1820 if (de->d_name[0] == '.')
1821 continue;
1822 namelen = strlen(de->d_name);
1823 if (namelen > 255)
1824 continue;
1825 if (has_extension(de->d_name, ".lock"))
1826 continue;
1827 memcpy(log + baselen, de->d_name, namelen+1);
1828 if (stat(git_path("logs/%s", log), &st) < 0)
1829 continue;
1830 if (S_ISDIR(st.st_mode)) {
1831 retval = do_for_each_reflog(log, fn, cb_data);
1832 } else {
1833 unsigned char sha1[20];
1834 if (!resolve_ref(log, sha1, 0, NULL))
1835 retval = error("bad ref for %s", log);
1836 else
1837 retval = fn(log, sha1, 0, cb_data);
1838 }
1839 if (retval)
1840 break;
1841 }
1842 free(log);
1843 closedir(dir);
1844 }
1845 else if (*base)
1846 return errno;
1847 return retval;
1848 }
1849
1850 int for_each_reflog(each_ref_fn fn, void *cb_data)
1851 {
1852 return do_for_each_reflog("", fn, cb_data);
1853 }
1854
1855 int update_ref(const char *action, const char *refname,
1856 const unsigned char *sha1, const unsigned char *oldval,
1857 int flags, enum action_on_err onerr)
1858 {
1859 static struct ref_lock *lock;
1860 lock = lock_any_ref_for_update(refname, oldval, flags);
1861 if (!lock) {
1862 const char *str = "Cannot lock the ref '%s'.";
1863 switch (onerr) {
1864 case MSG_ON_ERR: error(str, refname); break;
1865 case DIE_ON_ERR: die(str, refname); break;
1866 case QUIET_ON_ERR: break;
1867 }
1868 return 1;
1869 }
1870 if (write_ref_sha1(lock, sha1, action) < 0) {
1871 const char *str = "Cannot update the ref '%s'.";
1872 switch (onerr) {
1873 case MSG_ON_ERR: error(str, refname); break;
1874 case DIE_ON_ERR: die(str, refname); break;
1875 case QUIET_ON_ERR: break;
1876 }
1877 return 1;
1878 }
1879 return 0;
1880 }
1881
1882 int ref_exists(char *refname)
1883 {
1884 unsigned char sha1[20];
1885 return !!resolve_ref(refname, sha1, 1, NULL);
1886 }
1887
1888 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1889 {
1890 for ( ; list; list = list->next)
1891 if (!strcmp(list->name, name))
1892 return (struct ref *)list;
1893 return NULL;
1894 }
1895
1896 /*
1897 * generate a format suitable for scanf from a ref_rev_parse_rules
1898 * rule, that is replace the "%.*s" spec with a "%s" spec
1899 */
1900 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1901 {
1902 char *spec;
1903
1904 spec = strstr(rule, "%.*s");
1905 if (!spec || strstr(spec + 4, "%.*s"))
1906 die("invalid rule in ref_rev_parse_rules: %s", rule);
1907
1908 /* copy all until spec */
1909 strncpy(scanf_fmt, rule, spec - rule);
1910 scanf_fmt[spec - rule] = '\0';
1911 /* copy new spec */
1912 strcat(scanf_fmt, "%s");
1913 /* copy remaining rule */
1914 strcat(scanf_fmt, spec + 4);
1915
1916 return;
1917 }
1918
1919 char *shorten_unambiguous_ref(const char *ref, int strict)
1920 {
1921 int i;
1922 static char **scanf_fmts;
1923 static int nr_rules;
1924 char *short_name;
1925
1926 /* pre generate scanf formats from ref_rev_parse_rules[] */
1927 if (!nr_rules) {
1928 size_t total_len = 0;
1929
1930 /* the rule list is NULL terminated, count them first */
1931 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1932 /* no +1 because strlen("%s") < strlen("%.*s") */
1933 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1934
1935 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1936
1937 total_len = 0;
1938 for (i = 0; i < nr_rules; i++) {
1939 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1940 + total_len;
1941 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1942 total_len += strlen(ref_rev_parse_rules[i]);
1943 }
1944 }
1945
1946 /* bail out if there are no rules */
1947 if (!nr_rules)
1948 return xstrdup(ref);
1949
1950 /* buffer for scanf result, at most ref must fit */
1951 short_name = xstrdup(ref);
1952
1953 /* skip first rule, it will always match */
1954 for (i = nr_rules - 1; i > 0 ; --i) {
1955 int j;
1956 int rules_to_fail = i;
1957 int short_name_len;
1958
1959 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1960 continue;
1961
1962 short_name_len = strlen(short_name);
1963
1964 /*
1965 * in strict mode, all (except the matched one) rules
1966 * must fail to resolve to a valid non-ambiguous ref
1967 */
1968 if (strict)
1969 rules_to_fail = nr_rules;
1970
1971 /*
1972 * check if the short name resolves to a valid ref,
1973 * but use only rules prior to the matched one
1974 */
1975 for (j = 0; j < rules_to_fail; j++) {
1976 const char *rule = ref_rev_parse_rules[j];
1977 unsigned char short_objectname[20];
1978 char refname[PATH_MAX];
1979
1980 /* skip matched rule */
1981 if (i == j)
1982 continue;
1983
1984 /*
1985 * the short name is ambiguous, if it resolves
1986 * (with this previous rule) to a valid ref
1987 * read_ref() returns 0 on success
1988 */
1989 mksnpath(refname, sizeof(refname),
1990 rule, short_name_len, short_name);
1991 if (!read_ref(refname, short_objectname))
1992 break;
1993 }
1994
1995 /*
1996 * short name is non-ambiguous if all previous rules
1997 * haven't resolved to a valid ref
1998 */
1999 if (j == rules_to_fail)
2000 return short_name;
2001 }
2002
2003 free(short_name);
2004 return xstrdup(ref);
2005 }