add_ref(): verify that the refname is formatted correctly
[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 if (check_refname_format(name, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
60 die("Reference has invalid format: '%s'", name);
61 memcpy(entry->name, name, len);
62 entry->flag = flag;
63 entry->next = list;
64 if (new_entry)
65 *new_entry = entry;
66 return entry;
67 }
68
69 /* merge sort the ref list */
70 static struct ref_list *sort_ref_list(struct ref_list *list)
71 {
72 int psize, qsize, last_merge_count, cmp;
73 struct ref_list *p, *q, *l, *e;
74 struct ref_list *new_list = list;
75 int k = 1;
76 int merge_count = 0;
77
78 if (!list)
79 return list;
80
81 do {
82 last_merge_count = merge_count;
83 merge_count = 0;
84
85 psize = 0;
86
87 p = new_list;
88 q = new_list;
89 new_list = NULL;
90 l = NULL;
91
92 while (p) {
93 merge_count++;
94
95 while (psize < k && q->next) {
96 q = q->next;
97 psize++;
98 }
99 qsize = k;
100
101 while ((psize > 0) || (qsize > 0 && q)) {
102 if (qsize == 0 || !q) {
103 e = p;
104 p = p->next;
105 psize--;
106 } else if (psize == 0) {
107 e = q;
108 q = q->next;
109 qsize--;
110 } else {
111 cmp = strcmp(q->name, p->name);
112 if (cmp < 0) {
113 e = q;
114 q = q->next;
115 qsize--;
116 } else if (cmp > 0) {
117 e = p;
118 p = p->next;
119 psize--;
120 } else {
121 if (hashcmp(q->sha1, p->sha1))
122 die("Duplicated ref, and SHA1s don't match: %s",
123 q->name);
124 warning("Duplicated ref: %s", q->name);
125 e = q;
126 q = q->next;
127 qsize--;
128 free(e);
129 e = p;
130 p = p->next;
131 psize--;
132 }
133 }
134
135 e->next = NULL;
136
137 if (l)
138 l->next = e;
139 if (!new_list)
140 new_list = e;
141 l = e;
142 }
143
144 p = q;
145 };
146
147 k = k * 2;
148 } while ((last_merge_count != merge_count) || (last_merge_count != 1));
149
150 return new_list;
151 }
152
153 /*
154 * Future: need to be in "struct repository"
155 * when doing a full libification.
156 */
157 static struct cached_refs {
158 char did_loose;
159 char did_packed;
160 struct ref_list *loose;
161 struct ref_list *packed;
162 } cached_refs, submodule_refs;
163 static struct ref_list *current_ref;
164
165 static struct ref_list *extra_refs;
166
167 static void free_ref_list(struct ref_list *list)
168 {
169 struct ref_list *next;
170 for ( ; list; list = next) {
171 next = list->next;
172 free(list);
173 }
174 }
175
176 static void invalidate_cached_refs(void)
177 {
178 struct cached_refs *ca = &cached_refs;
179
180 if (ca->did_loose && ca->loose)
181 free_ref_list(ca->loose);
182 if (ca->did_packed && ca->packed)
183 free_ref_list(ca->packed);
184 ca->loose = ca->packed = NULL;
185 ca->did_loose = ca->did_packed = 0;
186 }
187
188 static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
189 {
190 struct ref_list *list = NULL;
191 struct ref_list *last = NULL;
192 char refline[PATH_MAX];
193 int flag = REF_ISPACKED;
194
195 while (fgets(refline, sizeof(refline), f)) {
196 unsigned char sha1[20];
197 const char *name;
198 static const char header[] = "# pack-refs with:";
199
200 if (!strncmp(refline, header, sizeof(header)-1)) {
201 const char *traits = refline + sizeof(header) - 1;
202 if (strstr(traits, " peeled "))
203 flag |= REF_KNOWS_PEELED;
204 /* perhaps other traits later as well */
205 continue;
206 }
207
208 name = parse_ref_line(refline, sha1);
209 if (name) {
210 list = add_ref(name, sha1, flag, list, &last);
211 continue;
212 }
213 if (last &&
214 refline[0] == '^' &&
215 strlen(refline) == 42 &&
216 refline[41] == '\n' &&
217 !get_sha1_hex(refline + 1, sha1))
218 hashcpy(last->peeled, sha1);
219 }
220 cached_refs->packed = sort_ref_list(list);
221 }
222
223 void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
224 {
225 extra_refs = add_ref(name, sha1, flag, extra_refs, NULL);
226 }
227
228 void clear_extra_refs(void)
229 {
230 free_ref_list(extra_refs);
231 extra_refs = NULL;
232 }
233
234 static struct ref_list *get_packed_refs(const char *submodule)
235 {
236 const char *packed_refs_file;
237 struct cached_refs *refs;
238
239 if (submodule) {
240 packed_refs_file = git_path_submodule(submodule, "packed-refs");
241 refs = &submodule_refs;
242 free_ref_list(refs->packed);
243 } else {
244 packed_refs_file = git_path("packed-refs");
245 refs = &cached_refs;
246 }
247
248 if (!refs->did_packed || submodule) {
249 FILE *f = fopen(packed_refs_file, "r");
250 refs->packed = NULL;
251 if (f) {
252 read_packed_refs(f, refs);
253 fclose(f);
254 }
255 refs->did_packed = 1;
256 }
257 return refs->packed;
258 }
259
260 static struct ref_list *get_ref_dir(const char *submodule, const char *base,
261 struct ref_list *list)
262 {
263 DIR *dir;
264 const char *path;
265
266 if (submodule)
267 path = git_path_submodule(submodule, "%s", base);
268 else
269 path = git_path("%s", base);
270
271
272 dir = opendir(path);
273
274 if (dir) {
275 struct dirent *de;
276 int baselen = strlen(base);
277 char *ref = xmalloc(baselen + 257);
278
279 memcpy(ref, base, baselen);
280 if (baselen && base[baselen-1] != '/')
281 ref[baselen++] = '/';
282
283 while ((de = readdir(dir)) != NULL) {
284 unsigned char sha1[20];
285 struct stat st;
286 int flag;
287 int namelen;
288 const char *refdir;
289
290 if (de->d_name[0] == '.')
291 continue;
292 namelen = strlen(de->d_name);
293 if (namelen > 255)
294 continue;
295 if (has_extension(de->d_name, ".lock"))
296 continue;
297 memcpy(ref + baselen, de->d_name, namelen+1);
298 refdir = submodule
299 ? git_path_submodule(submodule, "%s", ref)
300 : git_path("%s", ref);
301 if (stat(refdir, &st) < 0)
302 continue;
303 if (S_ISDIR(st.st_mode)) {
304 list = get_ref_dir(submodule, ref, list);
305 continue;
306 }
307 if (submodule) {
308 hashclr(sha1);
309 flag = 0;
310 if (resolve_gitlink_ref(submodule, ref, sha1) < 0) {
311 hashclr(sha1);
312 flag |= REF_BROKEN;
313 }
314 } else
315 if (!resolve_ref(ref, sha1, 1, &flag)) {
316 hashclr(sha1);
317 flag |= REF_BROKEN;
318 }
319 list = add_ref(ref, sha1, flag, list, NULL);
320 }
321 free(ref);
322 closedir(dir);
323 }
324 return sort_ref_list(list);
325 }
326
327 struct warn_if_dangling_data {
328 FILE *fp;
329 const char *refname;
330 const char *msg_fmt;
331 };
332
333 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
334 int flags, void *cb_data)
335 {
336 struct warn_if_dangling_data *d = cb_data;
337 const char *resolves_to;
338 unsigned char junk[20];
339
340 if (!(flags & REF_ISSYMREF))
341 return 0;
342
343 resolves_to = resolve_ref(refname, junk, 0, NULL);
344 if (!resolves_to || strcmp(resolves_to, d->refname))
345 return 0;
346
347 fprintf(d->fp, d->msg_fmt, refname);
348 return 0;
349 }
350
351 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
352 {
353 struct warn_if_dangling_data data;
354
355 data.fp = fp;
356 data.refname = refname;
357 data.msg_fmt = msg_fmt;
358 for_each_rawref(warn_if_dangling_symref, &data);
359 }
360
361 static struct ref_list *get_loose_refs(const char *submodule)
362 {
363 if (submodule) {
364 free_ref_list(submodule_refs.loose);
365 submodule_refs.loose = get_ref_dir(submodule, "refs", NULL);
366 return submodule_refs.loose;
367 }
368
369 if (!cached_refs.did_loose) {
370 cached_refs.loose = get_ref_dir(NULL, "refs", NULL);
371 cached_refs.did_loose = 1;
372 }
373 return cached_refs.loose;
374 }
375
376 /* We allow "recursive" symbolic refs. Only within reason, though */
377 #define MAXDEPTH 5
378 #define MAXREFLEN (1024)
379
380 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
381 {
382 FILE *f;
383 struct cached_refs refs;
384 struct ref_list *ref;
385 int retval;
386
387 strcpy(name + pathlen, "packed-refs");
388 f = fopen(name, "r");
389 if (!f)
390 return -1;
391 read_packed_refs(f, &refs);
392 fclose(f);
393 ref = refs.packed;
394 retval = -1;
395 while (ref) {
396 if (!strcmp(ref->name, refname)) {
397 retval = 0;
398 memcpy(result, ref->sha1, 20);
399 break;
400 }
401 ref = ref->next;
402 }
403 free_ref_list(refs.packed);
404 return retval;
405 }
406
407 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
408 {
409 int fd, len = strlen(refname);
410 char buffer[128], *p;
411
412 if (recursion > MAXDEPTH || len > MAXREFLEN)
413 return -1;
414 memcpy(name + pathlen, refname, len+1);
415 fd = open(name, O_RDONLY);
416 if (fd < 0)
417 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
418
419 len = read(fd, buffer, sizeof(buffer)-1);
420 close(fd);
421 if (len < 0)
422 return -1;
423 while (len && isspace(buffer[len-1]))
424 len--;
425 buffer[len] = 0;
426
427 /* Was it a detached head or an old-fashioned symlink? */
428 if (!get_sha1_hex(buffer, result))
429 return 0;
430
431 /* Symref? */
432 if (strncmp(buffer, "ref:", 4))
433 return -1;
434 p = buffer + 4;
435 while (isspace(*p))
436 p++;
437
438 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
439 }
440
441 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
442 {
443 int len = strlen(path), retval;
444 char *gitdir;
445 const char *tmp;
446
447 while (len && path[len-1] == '/')
448 len--;
449 if (!len)
450 return -1;
451 gitdir = xmalloc(len + MAXREFLEN + 8);
452 memcpy(gitdir, path, len);
453 memcpy(gitdir + len, "/.git", 6);
454 len += 5;
455
456 tmp = read_gitfile(gitdir);
457 if (tmp) {
458 free(gitdir);
459 len = strlen(tmp);
460 gitdir = xmalloc(len + MAXREFLEN + 3);
461 memcpy(gitdir, tmp, len);
462 }
463 gitdir[len] = '/';
464 gitdir[++len] = '\0';
465 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
466 free(gitdir);
467 return retval;
468 }
469
470 /*
471 * Try to read ref from the packed references. On success, set sha1
472 * and return 0; otherwise, return -1.
473 */
474 static int get_packed_ref(const char *ref, unsigned char *sha1)
475 {
476 struct ref_list *list = get_packed_refs(NULL);
477 while (list) {
478 if (!strcmp(ref, list->name)) {
479 hashcpy(sha1, list->sha1);
480 return 0;
481 }
482 list = list->next;
483 }
484 return -1;
485 }
486
487 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
488 {
489 int depth = MAXDEPTH;
490 ssize_t len;
491 char buffer[256];
492 static char ref_buffer[256];
493 char path[PATH_MAX];
494
495 if (flag)
496 *flag = 0;
497
498 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
499 return NULL;
500
501 for (;;) {
502 struct stat st;
503 char *buf;
504 int fd;
505
506 if (--depth < 0)
507 return NULL;
508
509 git_snpath(path, sizeof(path), "%s", ref);
510
511 if (lstat(path, &st) < 0) {
512 if (errno != ENOENT)
513 return NULL;
514 /*
515 * The loose reference file does not exist;
516 * check for a packed reference.
517 */
518 if (!get_packed_ref(ref, sha1)) {
519 if (flag)
520 *flag |= REF_ISPACKED;
521 return ref;
522 }
523 /* The reference is not a packed reference, either. */
524 if (reading) {
525 return NULL;
526 } else {
527 hashclr(sha1);
528 return ref;
529 }
530 }
531
532 /* Follow "normalized" - ie "refs/.." symlinks by hand */
533 if (S_ISLNK(st.st_mode)) {
534 len = readlink(path, buffer, sizeof(buffer)-1);
535 if (len < 0)
536 return NULL;
537 buffer[len] = 0;
538 if (!prefixcmp(buffer, "refs/") &&
539 !check_refname_format(buffer, 0)) {
540 strcpy(ref_buffer, buffer);
541 ref = ref_buffer;
542 if (flag)
543 *flag |= REF_ISSYMREF;
544 continue;
545 }
546 }
547
548 /* Is it a directory? */
549 if (S_ISDIR(st.st_mode)) {
550 errno = EISDIR;
551 return NULL;
552 }
553
554 /*
555 * Anything else, just open it and try to use it as
556 * a ref
557 */
558 fd = open(path, O_RDONLY);
559 if (fd < 0)
560 return NULL;
561 len = read_in_full(fd, buffer, sizeof(buffer)-1);
562 close(fd);
563 if (len < 0)
564 return NULL;
565 while (len && isspace(buffer[len-1]))
566 len--;
567 buffer[len] = '\0';
568
569 /*
570 * Is it a symbolic ref?
571 */
572 if (prefixcmp(buffer, "ref:"))
573 break;
574 buf = buffer + 4;
575 while (isspace(*buf))
576 buf++;
577 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
578 warning("symbolic reference in %s is formatted incorrectly",
579 path);
580 return NULL;
581 }
582 ref = strcpy(ref_buffer, buf);
583 if (flag)
584 *flag |= REF_ISSYMREF;
585 }
586 /* Please note that FETCH_HEAD has a second line containing other data. */
587 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
588 warning("reference in %s is formatted incorrectly", path);
589 return NULL;
590 }
591 return ref;
592 }
593
594 /* The argument to filter_refs */
595 struct ref_filter {
596 const char *pattern;
597 each_ref_fn *fn;
598 void *cb_data;
599 };
600
601 int read_ref(const char *ref, unsigned char *sha1)
602 {
603 if (resolve_ref(ref, sha1, 1, NULL))
604 return 0;
605 return -1;
606 }
607
608 #define DO_FOR_EACH_INCLUDE_BROKEN 01
609 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
610 int flags, void *cb_data, struct ref_list *entry)
611 {
612 if (prefixcmp(entry->name, base))
613 return 0;
614
615 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
616 if (entry->flag & REF_BROKEN)
617 return 0; /* ignore dangling symref */
618 if (!has_sha1_file(entry->sha1)) {
619 error("%s does not point to a valid object!", entry->name);
620 return 0;
621 }
622 }
623 current_ref = entry;
624 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
625 }
626
627 static int filter_refs(const char *ref, const unsigned char *sha, int flags,
628 void *data)
629 {
630 struct ref_filter *filter = (struct ref_filter *)data;
631 if (fnmatch(filter->pattern, ref, 0))
632 return 0;
633 return filter->fn(ref, sha, flags, filter->cb_data);
634 }
635
636 int peel_ref(const char *ref, unsigned char *sha1)
637 {
638 int flag;
639 unsigned char base[20];
640 struct object *o;
641
642 if (current_ref && (current_ref->name == ref
643 || !strcmp(current_ref->name, ref))) {
644 if (current_ref->flag & REF_KNOWS_PEELED) {
645 hashcpy(sha1, current_ref->peeled);
646 return 0;
647 }
648 hashcpy(base, current_ref->sha1);
649 goto fallback;
650 }
651
652 if (!resolve_ref(ref, base, 1, &flag))
653 return -1;
654
655 if ((flag & REF_ISPACKED)) {
656 struct ref_list *list = get_packed_refs(NULL);
657
658 while (list) {
659 if (!strcmp(list->name, ref)) {
660 if (list->flag & REF_KNOWS_PEELED) {
661 hashcpy(sha1, list->peeled);
662 return 0;
663 }
664 /* older pack-refs did not leave peeled ones */
665 break;
666 }
667 list = list->next;
668 }
669 }
670
671 fallback:
672 o = parse_object(base);
673 if (o && o->type == OBJ_TAG) {
674 o = deref_tag(o, ref, 0);
675 if (o) {
676 hashcpy(sha1, o->sha1);
677 return 0;
678 }
679 }
680 return -1;
681 }
682
683 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
684 int trim, int flags, void *cb_data)
685 {
686 int retval = 0;
687 struct ref_list *packed = get_packed_refs(submodule);
688 struct ref_list *loose = get_loose_refs(submodule);
689
690 struct ref_list *extra;
691
692 for (extra = extra_refs; extra; extra = extra->next)
693 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
694
695 while (packed && loose) {
696 struct ref_list *entry;
697 int cmp = strcmp(packed->name, loose->name);
698 if (!cmp) {
699 packed = packed->next;
700 continue;
701 }
702 if (cmp > 0) {
703 entry = loose;
704 loose = loose->next;
705 } else {
706 entry = packed;
707 packed = packed->next;
708 }
709 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
710 if (retval)
711 goto end_each;
712 }
713
714 for (packed = packed ? packed : loose; packed; packed = packed->next) {
715 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
716 if (retval)
717 goto end_each;
718 }
719
720 end_each:
721 current_ref = NULL;
722 return retval;
723 }
724
725
726 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
727 {
728 unsigned char sha1[20];
729 int flag;
730
731 if (submodule) {
732 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
733 return fn("HEAD", sha1, 0, cb_data);
734
735 return 0;
736 }
737
738 if (resolve_ref("HEAD", sha1, 1, &flag))
739 return fn("HEAD", sha1, flag, cb_data);
740
741 return 0;
742 }
743
744 int head_ref(each_ref_fn fn, void *cb_data)
745 {
746 return do_head_ref(NULL, fn, cb_data);
747 }
748
749 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
750 {
751 return do_head_ref(submodule, fn, cb_data);
752 }
753
754 int for_each_ref(each_ref_fn fn, void *cb_data)
755 {
756 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
757 }
758
759 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
760 {
761 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
762 }
763
764 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
765 {
766 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
767 }
768
769 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
770 each_ref_fn fn, void *cb_data)
771 {
772 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
773 }
774
775 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
776 {
777 return for_each_ref_in("refs/tags/", fn, cb_data);
778 }
779
780 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
781 {
782 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
783 }
784
785 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
786 {
787 return for_each_ref_in("refs/heads/", fn, cb_data);
788 }
789
790 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
791 {
792 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
793 }
794
795 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
796 {
797 return for_each_ref_in("refs/remotes/", fn, cb_data);
798 }
799
800 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
801 {
802 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
803 }
804
805 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
806 {
807 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
808 }
809
810 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
811 {
812 struct strbuf buf = STRBUF_INIT;
813 int ret = 0;
814 unsigned char sha1[20];
815 int flag;
816
817 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
818 if (resolve_ref(buf.buf, sha1, 1, &flag))
819 ret = fn(buf.buf, sha1, flag, cb_data);
820 strbuf_release(&buf);
821
822 return ret;
823 }
824
825 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
826 {
827 struct strbuf buf = STRBUF_INIT;
828 int ret;
829 strbuf_addf(&buf, "%srefs/", get_git_namespace());
830 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
831 strbuf_release(&buf);
832 return ret;
833 }
834
835 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
836 const char *prefix, void *cb_data)
837 {
838 struct strbuf real_pattern = STRBUF_INIT;
839 struct ref_filter filter;
840 int ret;
841
842 if (!prefix && prefixcmp(pattern, "refs/"))
843 strbuf_addstr(&real_pattern, "refs/");
844 else if (prefix)
845 strbuf_addstr(&real_pattern, prefix);
846 strbuf_addstr(&real_pattern, pattern);
847
848 if (!has_glob_specials(pattern)) {
849 /* Append implied '/' '*' if not present. */
850 if (real_pattern.buf[real_pattern.len - 1] != '/')
851 strbuf_addch(&real_pattern, '/');
852 /* No need to check for '*', there is none. */
853 strbuf_addch(&real_pattern, '*');
854 }
855
856 filter.pattern = real_pattern.buf;
857 filter.fn = fn;
858 filter.cb_data = cb_data;
859 ret = for_each_ref(filter_refs, &filter);
860
861 strbuf_release(&real_pattern);
862 return ret;
863 }
864
865 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
866 {
867 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
868 }
869
870 int for_each_rawref(each_ref_fn fn, void *cb_data)
871 {
872 return do_for_each_ref(NULL, "", fn, 0,
873 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
874 }
875
876 /*
877 * Make sure "ref" is something reasonable to have under ".git/refs/";
878 * We do not like it if:
879 *
880 * - any path component of it begins with ".", or
881 * - it has double dots "..", or
882 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
883 * - it ends with a "/".
884 * - it ends with ".lock"
885 * - it contains a "\" (backslash)
886 */
887
888 /* Return true iff ch is not allowed in reference names. */
889 static inline int bad_ref_char(int ch)
890 {
891 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
892 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
893 return 1;
894 /* 2.13 Pattern Matching Notation */
895 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
896 return 1;
897 return 0;
898 }
899
900 /*
901 * Try to read one refname component from the front of ref. Return
902 * the length of the component found, or -1 if the component is not
903 * legal.
904 */
905 static int check_refname_component(const char *ref, int flags)
906 {
907 const char *cp;
908 char last = '\0';
909
910 for (cp = ref; ; cp++) {
911 char ch = *cp;
912 if (ch == '\0' || ch == '/')
913 break;
914 if (bad_ref_char(ch))
915 return -1; /* Illegal character in refname. */
916 if (last == '.' && ch == '.')
917 return -1; /* Refname contains "..". */
918 if (last == '@' && ch == '{')
919 return -1; /* Refname contains "@{". */
920 last = ch;
921 }
922 if (cp == ref)
923 return -1; /* Component has zero length. */
924 if (ref[0] == '.') {
925 if (!(flags & REFNAME_DOT_COMPONENT))
926 return -1; /* Component starts with '.'. */
927 /*
928 * Even if leading dots are allowed, don't allow "."
929 * as a component (".." is prevented by a rule above).
930 */
931 if (ref[1] == '\0')
932 return -1; /* Component equals ".". */
933 }
934 if (cp - ref >= 5 && !memcmp(cp - 5, ".lock", 5))
935 return -1; /* Refname ends with ".lock". */
936 return cp - ref;
937 }
938
939 int check_refname_format(const char *ref, int flags)
940 {
941 int component_len, component_count = 0;
942
943 while (1) {
944 /* We are at the start of a path component. */
945 component_len = check_refname_component(ref, flags);
946 if (component_len < 0) {
947 if ((flags & REFNAME_REFSPEC_PATTERN) &&
948 ref[0] == '*' &&
949 (ref[1] == '\0' || ref[1] == '/')) {
950 /* Accept one wildcard as a full refname component. */
951 flags &= ~REFNAME_REFSPEC_PATTERN;
952 component_len = 1;
953 } else {
954 return -1;
955 }
956 }
957 component_count++;
958 if (ref[component_len] == '\0')
959 break;
960 /* Skip to next component. */
961 ref += component_len + 1;
962 }
963
964 if (ref[component_len - 1] == '.')
965 return -1; /* Refname ends with '.'. */
966 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
967 return -1; /* Refname has only one component. */
968 return 0;
969 }
970
971 const char *prettify_refname(const char *name)
972 {
973 return name + (
974 !prefixcmp(name, "refs/heads/") ? 11 :
975 !prefixcmp(name, "refs/tags/") ? 10 :
976 !prefixcmp(name, "refs/remotes/") ? 13 :
977 0);
978 }
979
980 const char *ref_rev_parse_rules[] = {
981 "%.*s",
982 "refs/%.*s",
983 "refs/tags/%.*s",
984 "refs/heads/%.*s",
985 "refs/remotes/%.*s",
986 "refs/remotes/%.*s/HEAD",
987 NULL
988 };
989
990 const char *ref_fetch_rules[] = {
991 "%.*s",
992 "refs/%.*s",
993 "refs/heads/%.*s",
994 NULL
995 };
996
997 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
998 {
999 const char **p;
1000 const int abbrev_name_len = strlen(abbrev_name);
1001
1002 for (p = rules; *p; p++) {
1003 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1004 return 1;
1005 }
1006 }
1007
1008 return 0;
1009 }
1010
1011 static struct ref_lock *verify_lock(struct ref_lock *lock,
1012 const unsigned char *old_sha1, int mustexist)
1013 {
1014 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
1015 error("Can't verify ref %s", lock->ref_name);
1016 unlock_ref(lock);
1017 return NULL;
1018 }
1019 if (hashcmp(lock->old_sha1, old_sha1)) {
1020 error("Ref %s is at %s but expected %s", lock->ref_name,
1021 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1022 unlock_ref(lock);
1023 return NULL;
1024 }
1025 return lock;
1026 }
1027
1028 static int remove_empty_directories(const char *file)
1029 {
1030 /* we want to create a file but there is a directory there;
1031 * if that is an empty directory (or a directory that contains
1032 * only empty directories), remove them.
1033 */
1034 struct strbuf path;
1035 int result;
1036
1037 strbuf_init(&path, 20);
1038 strbuf_addstr(&path, file);
1039
1040 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1041
1042 strbuf_release(&path);
1043
1044 return result;
1045 }
1046
1047 static int is_refname_available(const char *ref, const char *oldref,
1048 struct ref_list *list, int quiet)
1049 {
1050 int namlen = strlen(ref); /* e.g. 'foo/bar' */
1051 while (list) {
1052 /* list->name could be 'foo' or 'foo/bar/baz' */
1053 if (!oldref || strcmp(oldref, list->name)) {
1054 int len = strlen(list->name);
1055 int cmplen = (namlen < len) ? namlen : len;
1056 const char *lead = (namlen < len) ? list->name : ref;
1057 if (!strncmp(ref, list->name, cmplen) &&
1058 lead[cmplen] == '/') {
1059 if (!quiet)
1060 error("'%s' exists; cannot create '%s'",
1061 list->name, ref);
1062 return 0;
1063 }
1064 }
1065 list = list->next;
1066 }
1067 return 1;
1068 }
1069
1070 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
1071 {
1072 char *ref_file;
1073 const char *orig_ref = ref;
1074 struct ref_lock *lock;
1075 int last_errno = 0;
1076 int type, lflags;
1077 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1078 int missing = 0;
1079
1080 lock = xcalloc(1, sizeof(struct ref_lock));
1081 lock->lock_fd = -1;
1082
1083 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
1084 if (!ref && errno == EISDIR) {
1085 /* we are trying to lock foo but we used to
1086 * have foo/bar which now does not exist;
1087 * it is normal for the empty directory 'foo'
1088 * to remain.
1089 */
1090 ref_file = git_path("%s", orig_ref);
1091 if (remove_empty_directories(ref_file)) {
1092 last_errno = errno;
1093 error("there are still refs under '%s'", orig_ref);
1094 goto error_return;
1095 }
1096 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
1097 }
1098 if (type_p)
1099 *type_p = type;
1100 if (!ref) {
1101 last_errno = errno;
1102 error("unable to resolve reference %s: %s",
1103 orig_ref, strerror(errno));
1104 goto error_return;
1105 }
1106 missing = is_null_sha1(lock->old_sha1);
1107 /* When the ref did not exist and we are creating it,
1108 * make sure there is no existing ref that is packed
1109 * whose name begins with our refname, nor a ref whose
1110 * name is a proper prefix of our refname.
1111 */
1112 if (missing &&
1113 !is_refname_available(ref, NULL, get_packed_refs(NULL), 0)) {
1114 last_errno = ENOTDIR;
1115 goto error_return;
1116 }
1117
1118 lock->lk = xcalloc(1, sizeof(struct lock_file));
1119
1120 lflags = LOCK_DIE_ON_ERROR;
1121 if (flags & REF_NODEREF) {
1122 ref = orig_ref;
1123 lflags |= LOCK_NODEREF;
1124 }
1125 lock->ref_name = xstrdup(ref);
1126 lock->orig_ref_name = xstrdup(orig_ref);
1127 ref_file = git_path("%s", ref);
1128 if (missing)
1129 lock->force_write = 1;
1130 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1131 lock->force_write = 1;
1132
1133 if (safe_create_leading_directories(ref_file)) {
1134 last_errno = errno;
1135 error("unable to create directory for %s", ref_file);
1136 goto error_return;
1137 }
1138
1139 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1140 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1141
1142 error_return:
1143 unlock_ref(lock);
1144 errno = last_errno;
1145 return NULL;
1146 }
1147
1148 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
1149 {
1150 char refpath[PATH_MAX];
1151 if (check_refname_format(ref, 0))
1152 return NULL;
1153 strcpy(refpath, mkpath("refs/%s", ref));
1154 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1155 }
1156
1157 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
1158 {
1159 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
1160 return NULL;
1161 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1162 }
1163
1164 static struct lock_file packlock;
1165
1166 static int repack_without_ref(const char *refname)
1167 {
1168 struct ref_list *list, *packed_ref_list;
1169 int fd;
1170 int found = 0;
1171
1172 packed_ref_list = get_packed_refs(NULL);
1173 for (list = packed_ref_list; list; list = list->next) {
1174 if (!strcmp(refname, list->name)) {
1175 found = 1;
1176 break;
1177 }
1178 }
1179 if (!found)
1180 return 0;
1181 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1182 if (fd < 0) {
1183 unable_to_lock_error(git_path("packed-refs"), errno);
1184 return error("cannot delete '%s' from packed refs", refname);
1185 }
1186
1187 for (list = packed_ref_list; list; list = list->next) {
1188 char line[PATH_MAX + 100];
1189 int len;
1190
1191 if (!strcmp(refname, list->name))
1192 continue;
1193 len = snprintf(line, sizeof(line), "%s %s\n",
1194 sha1_to_hex(list->sha1), list->name);
1195 /* this should not happen but just being defensive */
1196 if (len > sizeof(line))
1197 die("too long a refname '%s'", list->name);
1198 write_or_die(fd, line, len);
1199 }
1200 return commit_lock_file(&packlock);
1201 }
1202
1203 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1204 {
1205 struct ref_lock *lock;
1206 int err, i = 0, ret = 0, flag = 0;
1207
1208 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1209 if (!lock)
1210 return 1;
1211 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1212 /* loose */
1213 const char *path;
1214
1215 if (!(delopt & REF_NODEREF)) {
1216 i = strlen(lock->lk->filename) - 5; /* .lock */
1217 lock->lk->filename[i] = 0;
1218 path = lock->lk->filename;
1219 } else {
1220 path = git_path("%s", refname);
1221 }
1222 err = unlink_or_warn(path);
1223 if (err && errno != ENOENT)
1224 ret = 1;
1225
1226 if (!(delopt & REF_NODEREF))
1227 lock->lk->filename[i] = '.';
1228 }
1229 /* removing the loose one could have resurrected an earlier
1230 * packed one. Also, if it was not loose we need to repack
1231 * without it.
1232 */
1233 ret |= repack_without_ref(refname);
1234
1235 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1236 invalidate_cached_refs();
1237 unlock_ref(lock);
1238 return ret;
1239 }
1240
1241 /*
1242 * People using contrib's git-new-workdir have .git/logs/refs ->
1243 * /some/other/path/.git/logs/refs, and that may live on another device.
1244 *
1245 * IOW, to avoid cross device rename errors, the temporary renamed log must
1246 * live into logs/refs.
1247 */
1248 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1249
1250 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1251 {
1252 static const char renamed_ref[] = "RENAMED-REF";
1253 unsigned char sha1[20], orig_sha1[20];
1254 int flag = 0, logmoved = 0;
1255 struct ref_lock *lock;
1256 struct stat loginfo;
1257 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1258 const char *symref = NULL;
1259
1260 if (log && S_ISLNK(loginfo.st_mode))
1261 return error("reflog for %s is a symlink", oldref);
1262
1263 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1264 if (flag & REF_ISSYMREF)
1265 return error("refname %s is a symbolic ref, renaming it is not supported",
1266 oldref);
1267 if (!symref)
1268 return error("refname %s not found", oldref);
1269
1270 if (!is_refname_available(newref, oldref, get_packed_refs(NULL), 0))
1271 return 1;
1272
1273 if (!is_refname_available(newref, oldref, get_loose_refs(NULL), 0))
1274 return 1;
1275
1276 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
1277 if (!lock)
1278 return error("unable to lock %s", renamed_ref);
1279 lock->force_write = 1;
1280 if (write_ref_sha1(lock, orig_sha1, logmsg))
1281 return error("unable to save current sha1 in %s", renamed_ref);
1282
1283 if (log && rename(git_path("logs/%s", oldref), git_path(TMP_RENAMED_LOG)))
1284 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1285 oldref, strerror(errno));
1286
1287 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1288 error("unable to delete old %s", oldref);
1289 goto rollback;
1290 }
1291
1292 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1293 if (errno==EISDIR) {
1294 if (remove_empty_directories(git_path("%s", newref))) {
1295 error("Directory not empty: %s", newref);
1296 goto rollback;
1297 }
1298 } else {
1299 error("unable to delete existing %s", newref);
1300 goto rollback;
1301 }
1302 }
1303
1304 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1305 error("unable to create directory for %s", newref);
1306 goto rollback;
1307 }
1308
1309 retry:
1310 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newref))) {
1311 if (errno==EISDIR || errno==ENOTDIR) {
1312 /*
1313 * rename(a, b) when b is an existing
1314 * directory ought to result in ISDIR, but
1315 * Solaris 5.8 gives ENOTDIR. Sheesh.
1316 */
1317 if (remove_empty_directories(git_path("logs/%s", newref))) {
1318 error("Directory not empty: logs/%s", newref);
1319 goto rollback;
1320 }
1321 goto retry;
1322 } else {
1323 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1324 newref, strerror(errno));
1325 goto rollback;
1326 }
1327 }
1328 logmoved = log;
1329
1330 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1331 if (!lock) {
1332 error("unable to lock %s for update", newref);
1333 goto rollback;
1334 }
1335 lock->force_write = 1;
1336 hashcpy(lock->old_sha1, orig_sha1);
1337 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1338 error("unable to write current sha1 into %s", newref);
1339 goto rollback;
1340 }
1341
1342 return 0;
1343
1344 rollback:
1345 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1346 if (!lock) {
1347 error("unable to lock %s for rollback", oldref);
1348 goto rollbacklog;
1349 }
1350
1351 lock->force_write = 1;
1352 flag = log_all_ref_updates;
1353 log_all_ref_updates = 0;
1354 if (write_ref_sha1(lock, orig_sha1, NULL))
1355 error("unable to write current sha1 into %s", oldref);
1356 log_all_ref_updates = flag;
1357
1358 rollbacklog:
1359 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1360 error("unable to restore logfile %s from %s: %s",
1361 oldref, newref, strerror(errno));
1362 if (!logmoved && log &&
1363 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldref)))
1364 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1365 oldref, strerror(errno));
1366
1367 return 1;
1368 }
1369
1370 int close_ref(struct ref_lock *lock)
1371 {
1372 if (close_lock_file(lock->lk))
1373 return -1;
1374 lock->lock_fd = -1;
1375 return 0;
1376 }
1377
1378 int commit_ref(struct ref_lock *lock)
1379 {
1380 if (commit_lock_file(lock->lk))
1381 return -1;
1382 lock->lock_fd = -1;
1383 return 0;
1384 }
1385
1386 void unlock_ref(struct ref_lock *lock)
1387 {
1388 /* Do not free lock->lk -- atexit() still looks at them */
1389 if (lock->lk)
1390 rollback_lock_file(lock->lk);
1391 free(lock->ref_name);
1392 free(lock->orig_ref_name);
1393 free(lock);
1394 }
1395
1396 /*
1397 * copy the reflog message msg to buf, which has been allocated sufficiently
1398 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1399 * because reflog file is one line per entry.
1400 */
1401 static int copy_msg(char *buf, const char *msg)
1402 {
1403 char *cp = buf;
1404 char c;
1405 int wasspace = 1;
1406
1407 *cp++ = '\t';
1408 while ((c = *msg++)) {
1409 if (wasspace && isspace(c))
1410 continue;
1411 wasspace = isspace(c);
1412 if (wasspace)
1413 c = ' ';
1414 *cp++ = c;
1415 }
1416 while (buf < cp && isspace(cp[-1]))
1417 cp--;
1418 *cp++ = '\n';
1419 return cp - buf;
1420 }
1421
1422 int log_ref_setup(const char *ref_name, char *logfile, int bufsize)
1423 {
1424 int logfd, oflags = O_APPEND | O_WRONLY;
1425
1426 git_snpath(logfile, bufsize, "logs/%s", ref_name);
1427 if (log_all_ref_updates &&
1428 (!prefixcmp(ref_name, "refs/heads/") ||
1429 !prefixcmp(ref_name, "refs/remotes/") ||
1430 !prefixcmp(ref_name, "refs/notes/") ||
1431 !strcmp(ref_name, "HEAD"))) {
1432 if (safe_create_leading_directories(logfile) < 0)
1433 return error("unable to create directory for %s",
1434 logfile);
1435 oflags |= O_CREAT;
1436 }
1437
1438 logfd = open(logfile, oflags, 0666);
1439 if (logfd < 0) {
1440 if (!(oflags & O_CREAT) && errno == ENOENT)
1441 return 0;
1442
1443 if ((oflags & O_CREAT) && errno == EISDIR) {
1444 if (remove_empty_directories(logfile)) {
1445 return error("There are still logs under '%s'",
1446 logfile);
1447 }
1448 logfd = open(logfile, oflags, 0666);
1449 }
1450
1451 if (logfd < 0)
1452 return error("Unable to append to %s: %s",
1453 logfile, strerror(errno));
1454 }
1455
1456 adjust_shared_perm(logfile);
1457 close(logfd);
1458 return 0;
1459 }
1460
1461 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1462 const unsigned char *new_sha1, const char *msg)
1463 {
1464 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1465 unsigned maxlen, len;
1466 int msglen;
1467 char log_file[PATH_MAX];
1468 char *logrec;
1469 const char *committer;
1470
1471 if (log_all_ref_updates < 0)
1472 log_all_ref_updates = !is_bare_repository();
1473
1474 result = log_ref_setup(ref_name, log_file, sizeof(log_file));
1475 if (result)
1476 return result;
1477
1478 logfd = open(log_file, oflags);
1479 if (logfd < 0)
1480 return 0;
1481 msglen = msg ? strlen(msg) : 0;
1482 committer = git_committer_info(0);
1483 maxlen = strlen(committer) + msglen + 100;
1484 logrec = xmalloc(maxlen);
1485 len = sprintf(logrec, "%s %s %s\n",
1486 sha1_to_hex(old_sha1),
1487 sha1_to_hex(new_sha1),
1488 committer);
1489 if (msglen)
1490 len += copy_msg(logrec + len - 1, msg) - 1;
1491 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1492 free(logrec);
1493 if (close(logfd) != 0 || written != len)
1494 return error("Unable to append to %s", log_file);
1495 return 0;
1496 }
1497
1498 static int is_branch(const char *refname)
1499 {
1500 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1501 }
1502
1503 int write_ref_sha1(struct ref_lock *lock,
1504 const unsigned char *sha1, const char *logmsg)
1505 {
1506 static char term = '\n';
1507 struct object *o;
1508
1509 if (!lock)
1510 return -1;
1511 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1512 unlock_ref(lock);
1513 return 0;
1514 }
1515 o = parse_object(sha1);
1516 if (!o) {
1517 error("Trying to write ref %s with nonexistent object %s",
1518 lock->ref_name, sha1_to_hex(sha1));
1519 unlock_ref(lock);
1520 return -1;
1521 }
1522 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1523 error("Trying to write non-commit object %s to branch %s",
1524 sha1_to_hex(sha1), lock->ref_name);
1525 unlock_ref(lock);
1526 return -1;
1527 }
1528 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1529 write_in_full(lock->lock_fd, &term, 1) != 1
1530 || close_ref(lock) < 0) {
1531 error("Couldn't write %s", lock->lk->filename);
1532 unlock_ref(lock);
1533 return -1;
1534 }
1535 invalidate_cached_refs();
1536 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1537 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1538 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1539 unlock_ref(lock);
1540 return -1;
1541 }
1542 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1543 /*
1544 * Special hack: If a branch is updated directly and HEAD
1545 * points to it (may happen on the remote side of a push
1546 * for example) then logically the HEAD reflog should be
1547 * updated too.
1548 * A generic solution implies reverse symref information,
1549 * but finding all symrefs pointing to the given branch
1550 * would be rather costly for this rare event (the direct
1551 * update of a branch) to be worth it. So let's cheat and
1552 * check with HEAD only which should cover 99% of all usage
1553 * scenarios (even 100% of the default ones).
1554 */
1555 unsigned char head_sha1[20];
1556 int head_flag;
1557 const char *head_ref;
1558 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1559 if (head_ref && (head_flag & REF_ISSYMREF) &&
1560 !strcmp(head_ref, lock->ref_name))
1561 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1562 }
1563 if (commit_ref(lock)) {
1564 error("Couldn't set %s", lock->ref_name);
1565 unlock_ref(lock);
1566 return -1;
1567 }
1568 unlock_ref(lock);
1569 return 0;
1570 }
1571
1572 int create_symref(const char *ref_target, const char *refs_heads_master,
1573 const char *logmsg)
1574 {
1575 const char *lockpath;
1576 char ref[1000];
1577 int fd, len, written;
1578 char *git_HEAD = git_pathdup("%s", ref_target);
1579 unsigned char old_sha1[20], new_sha1[20];
1580
1581 if (logmsg && read_ref(ref_target, old_sha1))
1582 hashclr(old_sha1);
1583
1584 if (safe_create_leading_directories(git_HEAD) < 0)
1585 return error("unable to create directory for %s", git_HEAD);
1586
1587 #ifndef NO_SYMLINK_HEAD
1588 if (prefer_symlink_refs) {
1589 unlink(git_HEAD);
1590 if (!symlink(refs_heads_master, git_HEAD))
1591 goto done;
1592 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1593 }
1594 #endif
1595
1596 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1597 if (sizeof(ref) <= len) {
1598 error("refname too long: %s", refs_heads_master);
1599 goto error_free_return;
1600 }
1601 lockpath = mkpath("%s.lock", git_HEAD);
1602 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1603 if (fd < 0) {
1604 error("Unable to open %s for writing", lockpath);
1605 goto error_free_return;
1606 }
1607 written = write_in_full(fd, ref, len);
1608 if (close(fd) != 0 || written != len) {
1609 error("Unable to write to %s", lockpath);
1610 goto error_unlink_return;
1611 }
1612 if (rename(lockpath, git_HEAD) < 0) {
1613 error("Unable to create %s", git_HEAD);
1614 goto error_unlink_return;
1615 }
1616 if (adjust_shared_perm(git_HEAD)) {
1617 error("Unable to fix permissions on %s", lockpath);
1618 error_unlink_return:
1619 unlink_or_warn(lockpath);
1620 error_free_return:
1621 free(git_HEAD);
1622 return -1;
1623 }
1624
1625 #ifndef NO_SYMLINK_HEAD
1626 done:
1627 #endif
1628 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1629 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1630
1631 free(git_HEAD);
1632 return 0;
1633 }
1634
1635 static char *ref_msg(const char *line, const char *endp)
1636 {
1637 const char *ep;
1638 line += 82;
1639 ep = memchr(line, '\n', endp - line);
1640 if (!ep)
1641 ep = endp;
1642 return xmemdupz(line, ep - line);
1643 }
1644
1645 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)
1646 {
1647 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1648 char *tz_c;
1649 int logfd, tz, reccnt = 0;
1650 struct stat st;
1651 unsigned long date;
1652 unsigned char logged_sha1[20];
1653 void *log_mapped;
1654 size_t mapsz;
1655
1656 logfile = git_path("logs/%s", ref);
1657 logfd = open(logfile, O_RDONLY, 0);
1658 if (logfd < 0)
1659 die_errno("Unable to read log '%s'", logfile);
1660 fstat(logfd, &st);
1661 if (!st.st_size)
1662 die("Log %s is empty.", logfile);
1663 mapsz = xsize_t(st.st_size);
1664 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1665 logdata = log_mapped;
1666 close(logfd);
1667
1668 lastrec = NULL;
1669 rec = logend = logdata + st.st_size;
1670 while (logdata < rec) {
1671 reccnt++;
1672 if (logdata < rec && *(rec-1) == '\n')
1673 rec--;
1674 lastgt = NULL;
1675 while (logdata < rec && *(rec-1) != '\n') {
1676 rec--;
1677 if (*rec == '>')
1678 lastgt = rec;
1679 }
1680 if (!lastgt)
1681 die("Log %s is corrupt.", logfile);
1682 date = strtoul(lastgt + 1, &tz_c, 10);
1683 if (date <= at_time || cnt == 0) {
1684 tz = strtoul(tz_c, NULL, 10);
1685 if (msg)
1686 *msg = ref_msg(rec, logend);
1687 if (cutoff_time)
1688 *cutoff_time = date;
1689 if (cutoff_tz)
1690 *cutoff_tz = tz;
1691 if (cutoff_cnt)
1692 *cutoff_cnt = reccnt - 1;
1693 if (lastrec) {
1694 if (get_sha1_hex(lastrec, logged_sha1))
1695 die("Log %s is corrupt.", logfile);
1696 if (get_sha1_hex(rec + 41, sha1))
1697 die("Log %s is corrupt.", logfile);
1698 if (hashcmp(logged_sha1, sha1)) {
1699 warning("Log %s has gap after %s.",
1700 logfile, show_date(date, tz, DATE_RFC2822));
1701 }
1702 }
1703 else if (date == at_time) {
1704 if (get_sha1_hex(rec + 41, sha1))
1705 die("Log %s is corrupt.", logfile);
1706 }
1707 else {
1708 if (get_sha1_hex(rec + 41, logged_sha1))
1709 die("Log %s is corrupt.", logfile);
1710 if (hashcmp(logged_sha1, sha1)) {
1711 warning("Log %s unexpectedly ended on %s.",
1712 logfile, show_date(date, tz, DATE_RFC2822));
1713 }
1714 }
1715 munmap(log_mapped, mapsz);
1716 return 0;
1717 }
1718 lastrec = rec;
1719 if (cnt > 0)
1720 cnt--;
1721 }
1722
1723 rec = logdata;
1724 while (rec < logend && *rec != '>' && *rec != '\n')
1725 rec++;
1726 if (rec == logend || *rec == '\n')
1727 die("Log %s is corrupt.", logfile);
1728 date = strtoul(rec + 1, &tz_c, 10);
1729 tz = strtoul(tz_c, NULL, 10);
1730 if (get_sha1_hex(logdata, sha1))
1731 die("Log %s is corrupt.", logfile);
1732 if (is_null_sha1(sha1)) {
1733 if (get_sha1_hex(logdata + 41, sha1))
1734 die("Log %s is corrupt.", logfile);
1735 }
1736 if (msg)
1737 *msg = ref_msg(logdata, logend);
1738 munmap(log_mapped, mapsz);
1739
1740 if (cutoff_time)
1741 *cutoff_time = date;
1742 if (cutoff_tz)
1743 *cutoff_tz = tz;
1744 if (cutoff_cnt)
1745 *cutoff_cnt = reccnt;
1746 return 1;
1747 }
1748
1749 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1750 {
1751 const char *logfile;
1752 FILE *logfp;
1753 struct strbuf sb = STRBUF_INIT;
1754 int ret = 0;
1755
1756 logfile = git_path("logs/%s", ref);
1757 logfp = fopen(logfile, "r");
1758 if (!logfp)
1759 return -1;
1760
1761 if (ofs) {
1762 struct stat statbuf;
1763 if (fstat(fileno(logfp), &statbuf) ||
1764 statbuf.st_size < ofs ||
1765 fseek(logfp, -ofs, SEEK_END) ||
1766 strbuf_getwholeline(&sb, logfp, '\n')) {
1767 fclose(logfp);
1768 strbuf_release(&sb);
1769 return -1;
1770 }
1771 }
1772
1773 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1774 unsigned char osha1[20], nsha1[20];
1775 char *email_end, *message;
1776 unsigned long timestamp;
1777 int tz;
1778
1779 /* old SP new SP name <email> SP time TAB msg LF */
1780 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1781 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1782 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1783 !(email_end = strchr(sb.buf + 82, '>')) ||
1784 email_end[1] != ' ' ||
1785 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1786 !message || message[0] != ' ' ||
1787 (message[1] != '+' && message[1] != '-') ||
1788 !isdigit(message[2]) || !isdigit(message[3]) ||
1789 !isdigit(message[4]) || !isdigit(message[5]))
1790 continue; /* corrupt? */
1791 email_end[1] = '\0';
1792 tz = strtol(message + 1, NULL, 10);
1793 if (message[6] != '\t')
1794 message += 6;
1795 else
1796 message += 7;
1797 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1798 cb_data);
1799 if (ret)
1800 break;
1801 }
1802 fclose(logfp);
1803 strbuf_release(&sb);
1804 return ret;
1805 }
1806
1807 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1808 {
1809 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1810 }
1811
1812 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1813 {
1814 DIR *dir = opendir(git_path("logs/%s", base));
1815 int retval = 0;
1816
1817 if (dir) {
1818 struct dirent *de;
1819 int baselen = strlen(base);
1820 char *log = xmalloc(baselen + 257);
1821
1822 memcpy(log, base, baselen);
1823 if (baselen && base[baselen-1] != '/')
1824 log[baselen++] = '/';
1825
1826 while ((de = readdir(dir)) != NULL) {
1827 struct stat st;
1828 int namelen;
1829
1830 if (de->d_name[0] == '.')
1831 continue;
1832 namelen = strlen(de->d_name);
1833 if (namelen > 255)
1834 continue;
1835 if (has_extension(de->d_name, ".lock"))
1836 continue;
1837 memcpy(log + baselen, de->d_name, namelen+1);
1838 if (stat(git_path("logs/%s", log), &st) < 0)
1839 continue;
1840 if (S_ISDIR(st.st_mode)) {
1841 retval = do_for_each_reflog(log, fn, cb_data);
1842 } else {
1843 unsigned char sha1[20];
1844 if (!resolve_ref(log, sha1, 0, NULL))
1845 retval = error("bad ref for %s", log);
1846 else
1847 retval = fn(log, sha1, 0, cb_data);
1848 }
1849 if (retval)
1850 break;
1851 }
1852 free(log);
1853 closedir(dir);
1854 }
1855 else if (*base)
1856 return errno;
1857 return retval;
1858 }
1859
1860 int for_each_reflog(each_ref_fn fn, void *cb_data)
1861 {
1862 return do_for_each_reflog("", fn, cb_data);
1863 }
1864
1865 int update_ref(const char *action, const char *refname,
1866 const unsigned char *sha1, const unsigned char *oldval,
1867 int flags, enum action_on_err onerr)
1868 {
1869 static struct ref_lock *lock;
1870 lock = lock_any_ref_for_update(refname, oldval, flags);
1871 if (!lock) {
1872 const char *str = "Cannot lock the ref '%s'.";
1873 switch (onerr) {
1874 case MSG_ON_ERR: error(str, refname); break;
1875 case DIE_ON_ERR: die(str, refname); break;
1876 case QUIET_ON_ERR: break;
1877 }
1878 return 1;
1879 }
1880 if (write_ref_sha1(lock, sha1, action) < 0) {
1881 const char *str = "Cannot update the ref '%s'.";
1882 switch (onerr) {
1883 case MSG_ON_ERR: error(str, refname); break;
1884 case DIE_ON_ERR: die(str, refname); break;
1885 case QUIET_ON_ERR: break;
1886 }
1887 return 1;
1888 }
1889 return 0;
1890 }
1891
1892 int ref_exists(char *refname)
1893 {
1894 unsigned char sha1[20];
1895 return !!resolve_ref(refname, sha1, 1, NULL);
1896 }
1897
1898 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1899 {
1900 for ( ; list; list = list->next)
1901 if (!strcmp(list->name, name))
1902 return (struct ref *)list;
1903 return NULL;
1904 }
1905
1906 /*
1907 * generate a format suitable for scanf from a ref_rev_parse_rules
1908 * rule, that is replace the "%.*s" spec with a "%s" spec
1909 */
1910 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1911 {
1912 char *spec;
1913
1914 spec = strstr(rule, "%.*s");
1915 if (!spec || strstr(spec + 4, "%.*s"))
1916 die("invalid rule in ref_rev_parse_rules: %s", rule);
1917
1918 /* copy all until spec */
1919 strncpy(scanf_fmt, rule, spec - rule);
1920 scanf_fmt[spec - rule] = '\0';
1921 /* copy new spec */
1922 strcat(scanf_fmt, "%s");
1923 /* copy remaining rule */
1924 strcat(scanf_fmt, spec + 4);
1925
1926 return;
1927 }
1928
1929 char *shorten_unambiguous_ref(const char *ref, int strict)
1930 {
1931 int i;
1932 static char **scanf_fmts;
1933 static int nr_rules;
1934 char *short_name;
1935
1936 /* pre generate scanf formats from ref_rev_parse_rules[] */
1937 if (!nr_rules) {
1938 size_t total_len = 0;
1939
1940 /* the rule list is NULL terminated, count them first */
1941 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1942 /* no +1 because strlen("%s") < strlen("%.*s") */
1943 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1944
1945 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1946
1947 total_len = 0;
1948 for (i = 0; i < nr_rules; i++) {
1949 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1950 + total_len;
1951 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1952 total_len += strlen(ref_rev_parse_rules[i]);
1953 }
1954 }
1955
1956 /* bail out if there are no rules */
1957 if (!nr_rules)
1958 return xstrdup(ref);
1959
1960 /* buffer for scanf result, at most ref must fit */
1961 short_name = xstrdup(ref);
1962
1963 /* skip first rule, it will always match */
1964 for (i = nr_rules - 1; i > 0 ; --i) {
1965 int j;
1966 int rules_to_fail = i;
1967 int short_name_len;
1968
1969 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1970 continue;
1971
1972 short_name_len = strlen(short_name);
1973
1974 /*
1975 * in strict mode, all (except the matched one) rules
1976 * must fail to resolve to a valid non-ambiguous ref
1977 */
1978 if (strict)
1979 rules_to_fail = nr_rules;
1980
1981 /*
1982 * check if the short name resolves to a valid ref,
1983 * but use only rules prior to the matched one
1984 */
1985 for (j = 0; j < rules_to_fail; j++) {
1986 const char *rule = ref_rev_parse_rules[j];
1987 unsigned char short_objectname[20];
1988 char refname[PATH_MAX];
1989
1990 /* skip matched rule */
1991 if (i == j)
1992 continue;
1993
1994 /*
1995 * the short name is ambiguous, if it resolves
1996 * (with this previous rule) to a valid ref
1997 * read_ref() returns 0 on success
1998 */
1999 mksnpath(refname, sizeof(refname),
2000 rule, short_name_len, short_name);
2001 if (!read_ref(refname, short_objectname))
2002 break;
2003 }
2004
2005 /*
2006 * short name is non-ambiguous if all previous rules
2007 * haven't resolved to a valid ref
2008 */
2009 if (j == rules_to_fail)
2010 return short_name;
2011 }
2012
2013 free(short_name);
2014 return xstrdup(ref);
2015 }