refs: add "for_each_ref_in" function to refactor "for_each_*_ref" functions
[git/git.git] / refs.c
1 #include "cache.h"
2 #include "refs.h"
3 #include "object.h"
4 #include "tag.h"
5 #include "dir.h"
6
7 /* ISSYMREF=01 and ISPACKED=02 are public interfaces */
8 #define REF_KNOWS_PEELED 04
9
10 struct ref_list {
11 struct ref_list *next;
12 unsigned char flag; /* ISSYMREF? ISPACKED? */
13 unsigned char sha1[20];
14 unsigned char peeled[20];
15 char name[FLEX_ARRAY];
16 };
17
18 static const char *parse_ref_line(char *line, unsigned char *sha1)
19 {
20 /*
21 * 42: the answer to everything.
22 *
23 * In this case, it happens to be the answer to
24 * 40 (length of sha1 hex representation)
25 * +1 (space in between hex and name)
26 * +1 (newline at the end of the line)
27 */
28 int len = strlen(line) - 42;
29
30 if (len <= 0)
31 return NULL;
32 if (get_sha1_hex(line, sha1) < 0)
33 return NULL;
34 if (!isspace(line[40]))
35 return NULL;
36 line += 41;
37 if (isspace(*line))
38 return NULL;
39 if (line[len] != '\n')
40 return NULL;
41 line[len] = 0;
42
43 return line;
44 }
45
46 static struct ref_list *add_ref(const char *name, const unsigned char *sha1,
47 int flag, struct ref_list *list,
48 struct ref_list **new_entry)
49 {
50 int len;
51 struct ref_list *entry;
52
53 /* Allocate it and add it in.. */
54 len = strlen(name) + 1;
55 entry = xmalloc(sizeof(struct ref_list) + len);
56 hashcpy(entry->sha1, sha1);
57 hashclr(entry->peeled);
58 memcpy(entry->name, name, len);
59 entry->flag = flag;
60 entry->next = list;
61 if (new_entry)
62 *new_entry = entry;
63 return entry;
64 }
65
66 /* merge sort the ref list */
67 static struct ref_list *sort_ref_list(struct ref_list *list)
68 {
69 int psize, qsize, last_merge_count, cmp;
70 struct ref_list *p, *q, *l, *e;
71 struct ref_list *new_list = list;
72 int k = 1;
73 int merge_count = 0;
74
75 if (!list)
76 return list;
77
78 do {
79 last_merge_count = merge_count;
80 merge_count = 0;
81
82 psize = 0;
83
84 p = new_list;
85 q = new_list;
86 new_list = NULL;
87 l = NULL;
88
89 while (p) {
90 merge_count++;
91
92 while (psize < k && q->next) {
93 q = q->next;
94 psize++;
95 }
96 qsize = k;
97
98 while ((psize > 0) || (qsize > 0 && q)) {
99 if (qsize == 0 || !q) {
100 e = p;
101 p = p->next;
102 psize--;
103 } else if (psize == 0) {
104 e = q;
105 q = q->next;
106 qsize--;
107 } else {
108 cmp = strcmp(q->name, p->name);
109 if (cmp < 0) {
110 e = q;
111 q = q->next;
112 qsize--;
113 } else if (cmp > 0) {
114 e = p;
115 p = p->next;
116 psize--;
117 } else {
118 if (hashcmp(q->sha1, p->sha1))
119 die("Duplicated ref, and SHA1s don't match: %s",
120 q->name);
121 warning("Duplicated ref: %s", q->name);
122 e = q;
123 q = q->next;
124 qsize--;
125 free(e);
126 e = p;
127 p = p->next;
128 psize--;
129 }
130 }
131
132 e->next = NULL;
133
134 if (l)
135 l->next = e;
136 if (!new_list)
137 new_list = e;
138 l = e;
139 }
140
141 p = q;
142 };
143
144 k = k * 2;
145 } while ((last_merge_count != merge_count) || (last_merge_count != 1));
146
147 return new_list;
148 }
149
150 /*
151 * Future: need to be in "struct repository"
152 * when doing a full libification.
153 */
154 static struct cached_refs {
155 char did_loose;
156 char did_packed;
157 struct ref_list *loose;
158 struct ref_list *packed;
159 } cached_refs;
160 static struct ref_list *current_ref;
161
162 static struct ref_list *extra_refs;
163
164 static void free_ref_list(struct ref_list *list)
165 {
166 struct ref_list *next;
167 for ( ; list; list = next) {
168 next = list->next;
169 free(list);
170 }
171 }
172
173 static void invalidate_cached_refs(void)
174 {
175 struct cached_refs *ca = &cached_refs;
176
177 if (ca->did_loose && ca->loose)
178 free_ref_list(ca->loose);
179 if (ca->did_packed && ca->packed)
180 free_ref_list(ca->packed);
181 ca->loose = ca->packed = NULL;
182 ca->did_loose = ca->did_packed = 0;
183 }
184
185 static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
186 {
187 struct ref_list *list = NULL;
188 struct ref_list *last = NULL;
189 char refline[PATH_MAX];
190 int flag = REF_ISPACKED;
191
192 while (fgets(refline, sizeof(refline), f)) {
193 unsigned char sha1[20];
194 const char *name;
195 static const char header[] = "# pack-refs with:";
196
197 if (!strncmp(refline, header, sizeof(header)-1)) {
198 const char *traits = refline + sizeof(header) - 1;
199 if (strstr(traits, " peeled "))
200 flag |= REF_KNOWS_PEELED;
201 /* perhaps other traits later as well */
202 continue;
203 }
204
205 name = parse_ref_line(refline, sha1);
206 if (name) {
207 list = add_ref(name, sha1, flag, list, &last);
208 continue;
209 }
210 if (last &&
211 refline[0] == '^' &&
212 strlen(refline) == 42 &&
213 refline[41] == '\n' &&
214 !get_sha1_hex(refline + 1, sha1))
215 hashcpy(last->peeled, sha1);
216 }
217 cached_refs->packed = sort_ref_list(list);
218 }
219
220 void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
221 {
222 extra_refs = add_ref(name, sha1, flag, extra_refs, NULL);
223 }
224
225 void clear_extra_refs(void)
226 {
227 free_ref_list(extra_refs);
228 extra_refs = NULL;
229 }
230
231 static struct ref_list *get_packed_refs(void)
232 {
233 if (!cached_refs.did_packed) {
234 FILE *f = fopen(git_path("packed-refs"), "r");
235 cached_refs.packed = NULL;
236 if (f) {
237 read_packed_refs(f, &cached_refs);
238 fclose(f);
239 }
240 cached_refs.did_packed = 1;
241 }
242 return cached_refs.packed;
243 }
244
245 static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
246 {
247 DIR *dir = opendir(git_path("%s", base));
248
249 if (dir) {
250 struct dirent *de;
251 int baselen = strlen(base);
252 char *ref = xmalloc(baselen + 257);
253
254 memcpy(ref, base, baselen);
255 if (baselen && base[baselen-1] != '/')
256 ref[baselen++] = '/';
257
258 while ((de = readdir(dir)) != NULL) {
259 unsigned char sha1[20];
260 struct stat st;
261 int flag;
262 int namelen;
263
264 if (de->d_name[0] == '.')
265 continue;
266 namelen = strlen(de->d_name);
267 if (namelen > 255)
268 continue;
269 if (has_extension(de->d_name, ".lock"))
270 continue;
271 memcpy(ref + baselen, de->d_name, namelen+1);
272 if (stat(git_path("%s", ref), &st) < 0)
273 continue;
274 if (S_ISDIR(st.st_mode)) {
275 list = get_ref_dir(ref, list);
276 continue;
277 }
278 if (!resolve_ref(ref, sha1, 1, &flag))
279 hashclr(sha1);
280 list = add_ref(ref, sha1, flag, list, NULL);
281 }
282 free(ref);
283 closedir(dir);
284 }
285 return sort_ref_list(list);
286 }
287
288 struct warn_if_dangling_data {
289 const char *refname;
290 const char *msg_fmt;
291 };
292
293 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
294 int flags, void *cb_data)
295 {
296 struct warn_if_dangling_data *d = cb_data;
297 const char *resolves_to;
298 unsigned char junk[20];
299
300 if (!(flags & REF_ISSYMREF))
301 return 0;
302
303 resolves_to = resolve_ref(refname, junk, 0, NULL);
304 if (!resolves_to || strcmp(resolves_to, d->refname))
305 return 0;
306
307 printf(d->msg_fmt, refname);
308 return 0;
309 }
310
311 void warn_dangling_symref(const char *msg_fmt, const char *refname)
312 {
313 struct warn_if_dangling_data data = { refname, msg_fmt };
314 for_each_rawref(warn_if_dangling_symref, &data);
315 }
316
317 static struct ref_list *get_loose_refs(void)
318 {
319 if (!cached_refs.did_loose) {
320 cached_refs.loose = get_ref_dir("refs", NULL);
321 cached_refs.did_loose = 1;
322 }
323 return cached_refs.loose;
324 }
325
326 /* We allow "recursive" symbolic refs. Only within reason, though */
327 #define MAXDEPTH 5
328 #define MAXREFLEN (1024)
329
330 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
331 {
332 FILE *f;
333 struct cached_refs refs;
334 struct ref_list *ref;
335 int retval;
336
337 strcpy(name + pathlen, "packed-refs");
338 f = fopen(name, "r");
339 if (!f)
340 return -1;
341 read_packed_refs(f, &refs);
342 fclose(f);
343 ref = refs.packed;
344 retval = -1;
345 while (ref) {
346 if (!strcmp(ref->name, refname)) {
347 retval = 0;
348 memcpy(result, ref->sha1, 20);
349 break;
350 }
351 ref = ref->next;
352 }
353 free_ref_list(refs.packed);
354 return retval;
355 }
356
357 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
358 {
359 int fd, len = strlen(refname);
360 char buffer[128], *p;
361
362 if (recursion > MAXDEPTH || len > MAXREFLEN)
363 return -1;
364 memcpy(name + pathlen, refname, len+1);
365 fd = open(name, O_RDONLY);
366 if (fd < 0)
367 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
368
369 len = read(fd, buffer, sizeof(buffer)-1);
370 close(fd);
371 if (len < 0)
372 return -1;
373 while (len && isspace(buffer[len-1]))
374 len--;
375 buffer[len] = 0;
376
377 /* Was it a detached head or an old-fashioned symlink? */
378 if (!get_sha1_hex(buffer, result))
379 return 0;
380
381 /* Symref? */
382 if (strncmp(buffer, "ref:", 4))
383 return -1;
384 p = buffer + 4;
385 while (isspace(*p))
386 p++;
387
388 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
389 }
390
391 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
392 {
393 int len = strlen(path), retval;
394 char *gitdir;
395 const char *tmp;
396
397 while (len && path[len-1] == '/')
398 len--;
399 if (!len)
400 return -1;
401 gitdir = xmalloc(len + MAXREFLEN + 8);
402 memcpy(gitdir, path, len);
403 memcpy(gitdir + len, "/.git", 6);
404 len += 5;
405
406 tmp = read_gitfile_gently(gitdir);
407 if (tmp) {
408 free(gitdir);
409 len = strlen(tmp);
410 gitdir = xmalloc(len + MAXREFLEN + 3);
411 memcpy(gitdir, tmp, len);
412 }
413 gitdir[len] = '/';
414 gitdir[++len] = '\0';
415 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
416 free(gitdir);
417 return retval;
418 }
419
420 /*
421 * If the "reading" argument is set, this function finds out what _object_
422 * the ref points at by "reading" the ref. The ref, if it is not symbolic,
423 * has to exist, and if it is symbolic, it has to point at an existing ref,
424 * because the "read" goes through the symref to the ref it points at.
425 *
426 * The access that is not "reading" may often be "writing", but does not
427 * have to; it can be merely checking _where it leads to_. If it is a
428 * prelude to "writing" to the ref, a write to a symref that points at
429 * yet-to-be-born ref will create the real ref pointed by the symref.
430 * reading=0 allows the caller to check where such a symref leads to.
431 */
432 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
433 {
434 int depth = MAXDEPTH;
435 ssize_t len;
436 char buffer[256];
437 static char ref_buffer[256];
438
439 if (flag)
440 *flag = 0;
441
442 for (;;) {
443 char path[PATH_MAX];
444 struct stat st;
445 char *buf;
446 int fd;
447
448 if (--depth < 0)
449 return NULL;
450
451 git_snpath(path, sizeof(path), "%s", ref);
452 /* Special case: non-existing file. */
453 if (lstat(path, &st) < 0) {
454 struct ref_list *list = get_packed_refs();
455 while (list) {
456 if (!strcmp(ref, list->name)) {
457 hashcpy(sha1, list->sha1);
458 if (flag)
459 *flag |= REF_ISPACKED;
460 return ref;
461 }
462 list = list->next;
463 }
464 if (reading || errno != ENOENT)
465 return NULL;
466 hashclr(sha1);
467 return ref;
468 }
469
470 /* Follow "normalized" - ie "refs/.." symlinks by hand */
471 if (S_ISLNK(st.st_mode)) {
472 len = readlink(path, buffer, sizeof(buffer)-1);
473 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
474 buffer[len] = 0;
475 strcpy(ref_buffer, buffer);
476 ref = ref_buffer;
477 if (flag)
478 *flag |= REF_ISSYMREF;
479 continue;
480 }
481 }
482
483 /* Is it a directory? */
484 if (S_ISDIR(st.st_mode)) {
485 errno = EISDIR;
486 return NULL;
487 }
488
489 /*
490 * Anything else, just open it and try to use it as
491 * a ref
492 */
493 fd = open(path, O_RDONLY);
494 if (fd < 0)
495 return NULL;
496 len = read_in_full(fd, buffer, sizeof(buffer)-1);
497 close(fd);
498
499 /*
500 * Is it a symbolic ref?
501 */
502 if (len < 4 || memcmp("ref:", buffer, 4))
503 break;
504 buf = buffer + 4;
505 len -= 4;
506 while (len && isspace(*buf))
507 buf++, len--;
508 while (len && isspace(buf[len-1]))
509 len--;
510 buf[len] = 0;
511 memcpy(ref_buffer, buf, len + 1);
512 ref = ref_buffer;
513 if (flag)
514 *flag |= REF_ISSYMREF;
515 }
516 if (len < 40 || get_sha1_hex(buffer, sha1))
517 return NULL;
518 return ref;
519 }
520
521 int read_ref(const char *ref, unsigned char *sha1)
522 {
523 if (resolve_ref(ref, sha1, 1, NULL))
524 return 0;
525 return -1;
526 }
527
528 #define DO_FOR_EACH_INCLUDE_BROKEN 01
529 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
530 int flags, void *cb_data, struct ref_list *entry)
531 {
532 if (strncmp(base, entry->name, trim))
533 return 0;
534 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
535 if (is_null_sha1(entry->sha1))
536 return 0;
537 if (!has_sha1_file(entry->sha1)) {
538 error("%s does not point to a valid object!", entry->name);
539 return 0;
540 }
541 }
542 current_ref = entry;
543 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
544 }
545
546 int peel_ref(const char *ref, unsigned char *sha1)
547 {
548 int flag;
549 unsigned char base[20];
550 struct object *o;
551
552 if (current_ref && (current_ref->name == ref
553 || !strcmp(current_ref->name, ref))) {
554 if (current_ref->flag & REF_KNOWS_PEELED) {
555 hashcpy(sha1, current_ref->peeled);
556 return 0;
557 }
558 hashcpy(base, current_ref->sha1);
559 goto fallback;
560 }
561
562 if (!resolve_ref(ref, base, 1, &flag))
563 return -1;
564
565 if ((flag & REF_ISPACKED)) {
566 struct ref_list *list = get_packed_refs();
567
568 while (list) {
569 if (!strcmp(list->name, ref)) {
570 if (list->flag & REF_KNOWS_PEELED) {
571 hashcpy(sha1, list->peeled);
572 return 0;
573 }
574 /* older pack-refs did not leave peeled ones */
575 break;
576 }
577 list = list->next;
578 }
579 }
580
581 fallback:
582 o = parse_object(base);
583 if (o && o->type == OBJ_TAG) {
584 o = deref_tag(o, ref, 0);
585 if (o) {
586 hashcpy(sha1, o->sha1);
587 return 0;
588 }
589 }
590 return -1;
591 }
592
593 static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
594 int flags, void *cb_data)
595 {
596 int retval = 0;
597 struct ref_list *packed = get_packed_refs();
598 struct ref_list *loose = get_loose_refs();
599
600 struct ref_list *extra;
601
602 for (extra = extra_refs; extra; extra = extra->next)
603 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
604
605 while (packed && loose) {
606 struct ref_list *entry;
607 int cmp = strcmp(packed->name, loose->name);
608 if (!cmp) {
609 packed = packed->next;
610 continue;
611 }
612 if (cmp > 0) {
613 entry = loose;
614 loose = loose->next;
615 } else {
616 entry = packed;
617 packed = packed->next;
618 }
619 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
620 if (retval)
621 goto end_each;
622 }
623
624 for (packed = packed ? packed : loose; packed; packed = packed->next) {
625 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
626 if (retval)
627 goto end_each;
628 }
629
630 end_each:
631 current_ref = NULL;
632 return retval;
633 }
634
635 int head_ref(each_ref_fn fn, void *cb_data)
636 {
637 unsigned char sha1[20];
638 int flag;
639
640 if (resolve_ref("HEAD", sha1, 1, &flag))
641 return fn("HEAD", sha1, flag, cb_data);
642 return 0;
643 }
644
645 int for_each_ref(each_ref_fn fn, void *cb_data)
646 {
647 return do_for_each_ref("refs/", fn, 0, 0, cb_data);
648 }
649
650 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
651 {
652 return do_for_each_ref(prefix, fn, strlen(prefix), 0, cb_data);
653 }
654
655 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
656 {
657 return for_each_ref_in("refs/tags/", fn, cb_data);
658 }
659
660 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
661 {
662 return for_each_ref_in("refs/heads/", fn, cb_data);
663 }
664
665 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
666 {
667 return for_each_ref_in("refs/remotes/", fn, cb_data);
668 }
669
670 int for_each_rawref(each_ref_fn fn, void *cb_data)
671 {
672 return do_for_each_ref("refs/", fn, 0,
673 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
674 }
675
676 /*
677 * Make sure "ref" is something reasonable to have under ".git/refs/";
678 * We do not like it if:
679 *
680 * - any path component of it begins with ".", or
681 * - it has double dots "..", or
682 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
683 * - it ends with a "/".
684 */
685
686 static inline int bad_ref_char(int ch)
687 {
688 if (((unsigned) ch) <= ' ' ||
689 ch == '~' || ch == '^' || ch == ':')
690 return 1;
691 /* 2.13 Pattern Matching Notation */
692 if (ch == '?' || ch == '[') /* Unsupported */
693 return 1;
694 if (ch == '*') /* Supported at the end */
695 return 2;
696 return 0;
697 }
698
699 int check_ref_format(const char *ref)
700 {
701 int ch, level, bad_type;
702 int ret = CHECK_REF_FORMAT_OK;
703 const char *cp = ref;
704
705 level = 0;
706 while (1) {
707 while ((ch = *cp++) == '/')
708 ; /* tolerate duplicated slashes */
709 if (!ch)
710 /* should not end with slashes */
711 return CHECK_REF_FORMAT_ERROR;
712
713 /* we are at the beginning of the path component */
714 if (ch == '.')
715 return CHECK_REF_FORMAT_ERROR;
716 bad_type = bad_ref_char(ch);
717 if (bad_type) {
718 if (bad_type == 2 && (!*cp || *cp == '/') &&
719 ret == CHECK_REF_FORMAT_OK)
720 ret = CHECK_REF_FORMAT_WILDCARD;
721 else
722 return CHECK_REF_FORMAT_ERROR;
723 }
724
725 /* scan the rest of the path component */
726 while ((ch = *cp++) != 0) {
727 bad_type = bad_ref_char(ch);
728 if (bad_type) {
729 return CHECK_REF_FORMAT_ERROR;
730 }
731 if (ch == '/')
732 break;
733 if (ch == '.' && *cp == '.')
734 return CHECK_REF_FORMAT_ERROR;
735 }
736 level++;
737 if (!ch) {
738 if (level < 2)
739 return CHECK_REF_FORMAT_ONELEVEL;
740 return ret;
741 }
742 }
743 }
744
745 const char *ref_rev_parse_rules[] = {
746 "%.*s",
747 "refs/%.*s",
748 "refs/tags/%.*s",
749 "refs/heads/%.*s",
750 "refs/remotes/%.*s",
751 "refs/remotes/%.*s/HEAD",
752 NULL
753 };
754
755 const char *ref_fetch_rules[] = {
756 "%.*s",
757 "refs/%.*s",
758 "refs/heads/%.*s",
759 NULL
760 };
761
762 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
763 {
764 const char **p;
765 const int abbrev_name_len = strlen(abbrev_name);
766
767 for (p = rules; *p; p++) {
768 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
769 return 1;
770 }
771 }
772
773 return 0;
774 }
775
776 static struct ref_lock *verify_lock(struct ref_lock *lock,
777 const unsigned char *old_sha1, int mustexist)
778 {
779 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
780 error("Can't verify ref %s", lock->ref_name);
781 unlock_ref(lock);
782 return NULL;
783 }
784 if (hashcmp(lock->old_sha1, old_sha1)) {
785 error("Ref %s is at %s but expected %s", lock->ref_name,
786 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
787 unlock_ref(lock);
788 return NULL;
789 }
790 return lock;
791 }
792
793 static int remove_empty_directories(const char *file)
794 {
795 /* we want to create a file but there is a directory there;
796 * if that is an empty directory (or a directory that contains
797 * only empty directories), remove them.
798 */
799 struct strbuf path;
800 int result;
801
802 strbuf_init(&path, 20);
803 strbuf_addstr(&path, file);
804
805 result = remove_dir_recursively(&path, 1);
806
807 strbuf_release(&path);
808
809 return result;
810 }
811
812 static int is_refname_available(const char *ref, const char *oldref,
813 struct ref_list *list, int quiet)
814 {
815 int namlen = strlen(ref); /* e.g. 'foo/bar' */
816 while (list) {
817 /* list->name could be 'foo' or 'foo/bar/baz' */
818 if (!oldref || strcmp(oldref, list->name)) {
819 int len = strlen(list->name);
820 int cmplen = (namlen < len) ? namlen : len;
821 const char *lead = (namlen < len) ? list->name : ref;
822 if (!strncmp(ref, list->name, cmplen) &&
823 lead[cmplen] == '/') {
824 if (!quiet)
825 error("'%s' exists; cannot create '%s'",
826 list->name, ref);
827 return 0;
828 }
829 }
830 list = list->next;
831 }
832 return 1;
833 }
834
835 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
836 {
837 char *ref_file;
838 const char *orig_ref = ref;
839 struct ref_lock *lock;
840 int last_errno = 0;
841 int type, lflags;
842 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
843 int missing = 0;
844
845 lock = xcalloc(1, sizeof(struct ref_lock));
846 lock->lock_fd = -1;
847
848 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
849 if (!ref && errno == EISDIR) {
850 /* we are trying to lock foo but we used to
851 * have foo/bar which now does not exist;
852 * it is normal for the empty directory 'foo'
853 * to remain.
854 */
855 ref_file = git_path("%s", orig_ref);
856 if (remove_empty_directories(ref_file)) {
857 last_errno = errno;
858 error("there are still refs under '%s'", orig_ref);
859 goto error_return;
860 }
861 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
862 }
863 if (type_p)
864 *type_p = type;
865 if (!ref) {
866 last_errno = errno;
867 error("unable to resolve reference %s: %s",
868 orig_ref, strerror(errno));
869 goto error_return;
870 }
871 missing = is_null_sha1(lock->old_sha1);
872 /* When the ref did not exist and we are creating it,
873 * make sure there is no existing ref that is packed
874 * whose name begins with our refname, nor a ref whose
875 * name is a proper prefix of our refname.
876 */
877 if (missing &&
878 !is_refname_available(ref, NULL, get_packed_refs(), 0))
879 goto error_return;
880
881 lock->lk = xcalloc(1, sizeof(struct lock_file));
882
883 lflags = LOCK_DIE_ON_ERROR;
884 if (flags & REF_NODEREF) {
885 ref = orig_ref;
886 lflags |= LOCK_NODEREF;
887 }
888 lock->ref_name = xstrdup(ref);
889 lock->orig_ref_name = xstrdup(orig_ref);
890 ref_file = git_path("%s", ref);
891 if (missing)
892 lock->force_write = 1;
893 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
894 lock->force_write = 1;
895
896 if (safe_create_leading_directories(ref_file)) {
897 last_errno = errno;
898 error("unable to create directory for %s", ref_file);
899 goto error_return;
900 }
901
902 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
903 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
904
905 error_return:
906 unlock_ref(lock);
907 errno = last_errno;
908 return NULL;
909 }
910
911 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
912 {
913 char refpath[PATH_MAX];
914 if (check_ref_format(ref))
915 return NULL;
916 strcpy(refpath, mkpath("refs/%s", ref));
917 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
918 }
919
920 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
921 {
922 switch (check_ref_format(ref)) {
923 default:
924 return NULL;
925 case 0:
926 case CHECK_REF_FORMAT_ONELEVEL:
927 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
928 }
929 }
930
931 static struct lock_file packlock;
932
933 static int repack_without_ref(const char *refname)
934 {
935 struct ref_list *list, *packed_ref_list;
936 int fd;
937 int found = 0;
938
939 packed_ref_list = get_packed_refs();
940 for (list = packed_ref_list; list; list = list->next) {
941 if (!strcmp(refname, list->name)) {
942 found = 1;
943 break;
944 }
945 }
946 if (!found)
947 return 0;
948 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
949 if (fd < 0)
950 return error("cannot delete '%s' from packed refs", refname);
951
952 for (list = packed_ref_list; list; list = list->next) {
953 char line[PATH_MAX + 100];
954 int len;
955
956 if (!strcmp(refname, list->name))
957 continue;
958 len = snprintf(line, sizeof(line), "%s %s\n",
959 sha1_to_hex(list->sha1), list->name);
960 /* this should not happen but just being defensive */
961 if (len > sizeof(line))
962 die("too long a refname '%s'", list->name);
963 write_or_die(fd, line, len);
964 }
965 return commit_lock_file(&packlock);
966 }
967
968 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
969 {
970 struct ref_lock *lock;
971 int err, i = 0, ret = 0, flag = 0;
972
973 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
974 if (!lock)
975 return 1;
976 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
977 /* loose */
978 const char *path;
979
980 if (!(delopt & REF_NODEREF)) {
981 i = strlen(lock->lk->filename) - 5; /* .lock */
982 lock->lk->filename[i] = 0;
983 path = lock->lk->filename;
984 } else {
985 path = git_path("%s", refname);
986 }
987 err = unlink(path);
988 if (err && errno != ENOENT) {
989 ret = 1;
990 error("unlink(%s) failed: %s",
991 path, strerror(errno));
992 }
993 if (!(delopt & REF_NODEREF))
994 lock->lk->filename[i] = '.';
995 }
996 /* removing the loose one could have resurrected an earlier
997 * packed one. Also, if it was not loose we need to repack
998 * without it.
999 */
1000 ret |= repack_without_ref(refname);
1001
1002 err = unlink(git_path("logs/%s", lock->ref_name));
1003 if (err && errno != ENOENT)
1004 warning("unlink(%s) failed: %s",
1005 git_path("logs/%s", lock->ref_name), strerror(errno));
1006 invalidate_cached_refs();
1007 unlock_ref(lock);
1008 return ret;
1009 }
1010
1011 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1012 {
1013 static const char renamed_ref[] = "RENAMED-REF";
1014 unsigned char sha1[20], orig_sha1[20];
1015 int flag = 0, logmoved = 0;
1016 struct ref_lock *lock;
1017 struct stat loginfo;
1018 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1019 const char *symref = NULL;
1020
1021 if (log && S_ISLNK(loginfo.st_mode))
1022 return error("reflog for %s is a symlink", oldref);
1023
1024 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1025 if (flag & REF_ISSYMREF)
1026 return error("refname %s is a symbolic ref, renaming it is not supported",
1027 oldref);
1028 if (!symref)
1029 return error("refname %s not found", oldref);
1030
1031 if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
1032 return 1;
1033
1034 if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
1035 return 1;
1036
1037 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
1038 if (!lock)
1039 return error("unable to lock %s", renamed_ref);
1040 lock->force_write = 1;
1041 if (write_ref_sha1(lock, orig_sha1, logmsg))
1042 return error("unable to save current sha1 in %s", renamed_ref);
1043
1044 if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
1045 return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
1046 oldref, strerror(errno));
1047
1048 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1049 error("unable to delete old %s", oldref);
1050 goto rollback;
1051 }
1052
1053 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1054 if (errno==EISDIR) {
1055 if (remove_empty_directories(git_path("%s", newref))) {
1056 error("Directory not empty: %s", newref);
1057 goto rollback;
1058 }
1059 } else {
1060 error("unable to delete existing %s", newref);
1061 goto rollback;
1062 }
1063 }
1064
1065 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1066 error("unable to create directory for %s", newref);
1067 goto rollback;
1068 }
1069
1070 retry:
1071 if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
1072 if (errno==EISDIR || errno==ENOTDIR) {
1073 /*
1074 * rename(a, b) when b is an existing
1075 * directory ought to result in ISDIR, but
1076 * Solaris 5.8 gives ENOTDIR. Sheesh.
1077 */
1078 if (remove_empty_directories(git_path("logs/%s", newref))) {
1079 error("Directory not empty: logs/%s", newref);
1080 goto rollback;
1081 }
1082 goto retry;
1083 } else {
1084 error("unable to move logfile tmp-renamed-log to logs/%s: %s",
1085 newref, strerror(errno));
1086 goto rollback;
1087 }
1088 }
1089 logmoved = log;
1090
1091 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1092 if (!lock) {
1093 error("unable to lock %s for update", newref);
1094 goto rollback;
1095 }
1096 lock->force_write = 1;
1097 hashcpy(lock->old_sha1, orig_sha1);
1098 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1099 error("unable to write current sha1 into %s", newref);
1100 goto rollback;
1101 }
1102
1103 return 0;
1104
1105 rollback:
1106 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1107 if (!lock) {
1108 error("unable to lock %s for rollback", oldref);
1109 goto rollbacklog;
1110 }
1111
1112 lock->force_write = 1;
1113 flag = log_all_ref_updates;
1114 log_all_ref_updates = 0;
1115 if (write_ref_sha1(lock, orig_sha1, NULL))
1116 error("unable to write current sha1 into %s", oldref);
1117 log_all_ref_updates = flag;
1118
1119 rollbacklog:
1120 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1121 error("unable to restore logfile %s from %s: %s",
1122 oldref, newref, strerror(errno));
1123 if (!logmoved && log &&
1124 rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
1125 error("unable to restore logfile %s from tmp-renamed-log: %s",
1126 oldref, strerror(errno));
1127
1128 return 1;
1129 }
1130
1131 int close_ref(struct ref_lock *lock)
1132 {
1133 if (close_lock_file(lock->lk))
1134 return -1;
1135 lock->lock_fd = -1;
1136 return 0;
1137 }
1138
1139 int commit_ref(struct ref_lock *lock)
1140 {
1141 if (commit_lock_file(lock->lk))
1142 return -1;
1143 lock->lock_fd = -1;
1144 return 0;
1145 }
1146
1147 void unlock_ref(struct ref_lock *lock)
1148 {
1149 /* Do not free lock->lk -- atexit() still looks at them */
1150 if (lock->lk)
1151 rollback_lock_file(lock->lk);
1152 free(lock->ref_name);
1153 free(lock->orig_ref_name);
1154 free(lock);
1155 }
1156
1157 /*
1158 * copy the reflog message msg to buf, which has been allocated sufficiently
1159 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1160 * because reflog file is one line per entry.
1161 */
1162 static int copy_msg(char *buf, const char *msg)
1163 {
1164 char *cp = buf;
1165 char c;
1166 int wasspace = 1;
1167
1168 *cp++ = '\t';
1169 while ((c = *msg++)) {
1170 if (wasspace && isspace(c))
1171 continue;
1172 wasspace = isspace(c);
1173 if (wasspace)
1174 c = ' ';
1175 *cp++ = c;
1176 }
1177 while (buf < cp && isspace(cp[-1]))
1178 cp--;
1179 *cp++ = '\n';
1180 return cp - buf;
1181 }
1182
1183 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1184 const unsigned char *new_sha1, const char *msg)
1185 {
1186 int logfd, written, oflags = O_APPEND | O_WRONLY;
1187 unsigned maxlen, len;
1188 int msglen;
1189 char log_file[PATH_MAX];
1190 char *logrec;
1191 const char *committer;
1192
1193 if (log_all_ref_updates < 0)
1194 log_all_ref_updates = !is_bare_repository();
1195
1196 git_snpath(log_file, sizeof(log_file), "logs/%s", ref_name);
1197
1198 if (log_all_ref_updates &&
1199 (!prefixcmp(ref_name, "refs/heads/") ||
1200 !prefixcmp(ref_name, "refs/remotes/") ||
1201 !strcmp(ref_name, "HEAD"))) {
1202 if (safe_create_leading_directories(log_file) < 0)
1203 return error("unable to create directory for %s",
1204 log_file);
1205 oflags |= O_CREAT;
1206 }
1207
1208 logfd = open(log_file, oflags, 0666);
1209 if (logfd < 0) {
1210 if (!(oflags & O_CREAT) && errno == ENOENT)
1211 return 0;
1212
1213 if ((oflags & O_CREAT) && errno == EISDIR) {
1214 if (remove_empty_directories(log_file)) {
1215 return error("There are still logs under '%s'",
1216 log_file);
1217 }
1218 logfd = open(log_file, oflags, 0666);
1219 }
1220
1221 if (logfd < 0)
1222 return error("Unable to append to %s: %s",
1223 log_file, strerror(errno));
1224 }
1225
1226 adjust_shared_perm(log_file);
1227
1228 msglen = msg ? strlen(msg) : 0;
1229 committer = git_committer_info(0);
1230 maxlen = strlen(committer) + msglen + 100;
1231 logrec = xmalloc(maxlen);
1232 len = sprintf(logrec, "%s %s %s\n",
1233 sha1_to_hex(old_sha1),
1234 sha1_to_hex(new_sha1),
1235 committer);
1236 if (msglen)
1237 len += copy_msg(logrec + len - 1, msg) - 1;
1238 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1239 free(logrec);
1240 if (close(logfd) != 0 || written != len)
1241 return error("Unable to append to %s", log_file);
1242 return 0;
1243 }
1244
1245 static int is_branch(const char *refname)
1246 {
1247 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1248 }
1249
1250 int write_ref_sha1(struct ref_lock *lock,
1251 const unsigned char *sha1, const char *logmsg)
1252 {
1253 static char term = '\n';
1254 struct object *o;
1255
1256 if (!lock)
1257 return -1;
1258 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1259 unlock_ref(lock);
1260 return 0;
1261 }
1262 o = parse_object(sha1);
1263 if (!o) {
1264 error("Trying to write ref %s with nonexistant object %s",
1265 lock->ref_name, sha1_to_hex(sha1));
1266 unlock_ref(lock);
1267 return -1;
1268 }
1269 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1270 error("Trying to write non-commit object %s to branch %s",
1271 sha1_to_hex(sha1), lock->ref_name);
1272 unlock_ref(lock);
1273 return -1;
1274 }
1275 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1276 write_in_full(lock->lock_fd, &term, 1) != 1
1277 || close_ref(lock) < 0) {
1278 error("Couldn't write %s", lock->lk->filename);
1279 unlock_ref(lock);
1280 return -1;
1281 }
1282 invalidate_cached_refs();
1283 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1284 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1285 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1286 unlock_ref(lock);
1287 return -1;
1288 }
1289 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1290 /*
1291 * Special hack: If a branch is updated directly and HEAD
1292 * points to it (may happen on the remote side of a push
1293 * for example) then logically the HEAD reflog should be
1294 * updated too.
1295 * A generic solution implies reverse symref information,
1296 * but finding all symrefs pointing to the given branch
1297 * would be rather costly for this rare event (the direct
1298 * update of a branch) to be worth it. So let's cheat and
1299 * check with HEAD only which should cover 99% of all usage
1300 * scenarios (even 100% of the default ones).
1301 */
1302 unsigned char head_sha1[20];
1303 int head_flag;
1304 const char *head_ref;
1305 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1306 if (head_ref && (head_flag & REF_ISSYMREF) &&
1307 !strcmp(head_ref, lock->ref_name))
1308 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1309 }
1310 if (commit_ref(lock)) {
1311 error("Couldn't set %s", lock->ref_name);
1312 unlock_ref(lock);
1313 return -1;
1314 }
1315 unlock_ref(lock);
1316 return 0;
1317 }
1318
1319 int create_symref(const char *ref_target, const char *refs_heads_master,
1320 const char *logmsg)
1321 {
1322 const char *lockpath;
1323 char ref[1000];
1324 int fd, len, written;
1325 char *git_HEAD = git_pathdup("%s", ref_target);
1326 unsigned char old_sha1[20], new_sha1[20];
1327
1328 if (logmsg && read_ref(ref_target, old_sha1))
1329 hashclr(old_sha1);
1330
1331 if (safe_create_leading_directories(git_HEAD) < 0)
1332 return error("unable to create directory for %s", git_HEAD);
1333
1334 #ifndef NO_SYMLINK_HEAD
1335 if (prefer_symlink_refs) {
1336 unlink(git_HEAD);
1337 if (!symlink(refs_heads_master, git_HEAD))
1338 goto done;
1339 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1340 }
1341 #endif
1342
1343 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1344 if (sizeof(ref) <= len) {
1345 error("refname too long: %s", refs_heads_master);
1346 goto error_free_return;
1347 }
1348 lockpath = mkpath("%s.lock", git_HEAD);
1349 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1350 if (fd < 0) {
1351 error("Unable to open %s for writing", lockpath);
1352 goto error_free_return;
1353 }
1354 written = write_in_full(fd, ref, len);
1355 if (close(fd) != 0 || written != len) {
1356 error("Unable to write to %s", lockpath);
1357 goto error_unlink_return;
1358 }
1359 if (rename(lockpath, git_HEAD) < 0) {
1360 error("Unable to create %s", git_HEAD);
1361 goto error_unlink_return;
1362 }
1363 if (adjust_shared_perm(git_HEAD)) {
1364 error("Unable to fix permissions on %s", lockpath);
1365 error_unlink_return:
1366 unlink(lockpath);
1367 error_free_return:
1368 free(git_HEAD);
1369 return -1;
1370 }
1371
1372 #ifndef NO_SYMLINK_HEAD
1373 done:
1374 #endif
1375 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1376 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1377
1378 free(git_HEAD);
1379 return 0;
1380 }
1381
1382 static char *ref_msg(const char *line, const char *endp)
1383 {
1384 const char *ep;
1385 line += 82;
1386 ep = memchr(line, '\n', endp - line);
1387 if (!ep)
1388 ep = endp;
1389 return xmemdupz(line, ep - line);
1390 }
1391
1392 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)
1393 {
1394 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1395 char *tz_c;
1396 int logfd, tz, reccnt = 0;
1397 struct stat st;
1398 unsigned long date;
1399 unsigned char logged_sha1[20];
1400 void *log_mapped;
1401 size_t mapsz;
1402
1403 logfile = git_path("logs/%s", ref);
1404 logfd = open(logfile, O_RDONLY, 0);
1405 if (logfd < 0)
1406 die("Unable to read log %s: %s", logfile, strerror(errno));
1407 fstat(logfd, &st);
1408 if (!st.st_size)
1409 die("Log %s is empty.", logfile);
1410 mapsz = xsize_t(st.st_size);
1411 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1412 logdata = log_mapped;
1413 close(logfd);
1414
1415 lastrec = NULL;
1416 rec = logend = logdata + st.st_size;
1417 while (logdata < rec) {
1418 reccnt++;
1419 if (logdata < rec && *(rec-1) == '\n')
1420 rec--;
1421 lastgt = NULL;
1422 while (logdata < rec && *(rec-1) != '\n') {
1423 rec--;
1424 if (*rec == '>')
1425 lastgt = rec;
1426 }
1427 if (!lastgt)
1428 die("Log %s is corrupt.", logfile);
1429 date = strtoul(lastgt + 1, &tz_c, 10);
1430 if (date <= at_time || cnt == 0) {
1431 tz = strtoul(tz_c, NULL, 10);
1432 if (msg)
1433 *msg = ref_msg(rec, logend);
1434 if (cutoff_time)
1435 *cutoff_time = date;
1436 if (cutoff_tz)
1437 *cutoff_tz = tz;
1438 if (cutoff_cnt)
1439 *cutoff_cnt = reccnt - 1;
1440 if (lastrec) {
1441 if (get_sha1_hex(lastrec, logged_sha1))
1442 die("Log %s is corrupt.", logfile);
1443 if (get_sha1_hex(rec + 41, sha1))
1444 die("Log %s is corrupt.", logfile);
1445 if (hashcmp(logged_sha1, sha1)) {
1446 warning("Log %s has gap after %s.",
1447 logfile, show_date(date, tz, DATE_RFC2822));
1448 }
1449 }
1450 else if (date == at_time) {
1451 if (get_sha1_hex(rec + 41, sha1))
1452 die("Log %s is corrupt.", logfile);
1453 }
1454 else {
1455 if (get_sha1_hex(rec + 41, logged_sha1))
1456 die("Log %s is corrupt.", logfile);
1457 if (hashcmp(logged_sha1, sha1)) {
1458 warning("Log %s unexpectedly ended on %s.",
1459 logfile, show_date(date, tz, DATE_RFC2822));
1460 }
1461 }
1462 munmap(log_mapped, mapsz);
1463 return 0;
1464 }
1465 lastrec = rec;
1466 if (cnt > 0)
1467 cnt--;
1468 }
1469
1470 rec = logdata;
1471 while (rec < logend && *rec != '>' && *rec != '\n')
1472 rec++;
1473 if (rec == logend || *rec == '\n')
1474 die("Log %s is corrupt.", logfile);
1475 date = strtoul(rec + 1, &tz_c, 10);
1476 tz = strtoul(tz_c, NULL, 10);
1477 if (get_sha1_hex(logdata, sha1))
1478 die("Log %s is corrupt.", logfile);
1479 if (is_null_sha1(sha1)) {
1480 if (get_sha1_hex(logdata + 41, sha1))
1481 die("Log %s is corrupt.", logfile);
1482 }
1483 if (msg)
1484 *msg = ref_msg(logdata, logend);
1485 munmap(log_mapped, mapsz);
1486
1487 if (cutoff_time)
1488 *cutoff_time = date;
1489 if (cutoff_tz)
1490 *cutoff_tz = tz;
1491 if (cutoff_cnt)
1492 *cutoff_cnt = reccnt;
1493 return 1;
1494 }
1495
1496 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1497 {
1498 const char *logfile;
1499 FILE *logfp;
1500 char buf[1024];
1501 int ret = 0;
1502
1503 logfile = git_path("logs/%s", ref);
1504 logfp = fopen(logfile, "r");
1505 if (!logfp)
1506 return -1;
1507
1508 if (ofs) {
1509 struct stat statbuf;
1510 if (fstat(fileno(logfp), &statbuf) ||
1511 statbuf.st_size < ofs ||
1512 fseek(logfp, -ofs, SEEK_END) ||
1513 fgets(buf, sizeof(buf), logfp))
1514 return -1;
1515 }
1516
1517 while (fgets(buf, sizeof(buf), logfp)) {
1518 unsigned char osha1[20], nsha1[20];
1519 char *email_end, *message;
1520 unsigned long timestamp;
1521 int len, tz;
1522
1523 /* old SP new SP name <email> SP time TAB msg LF */
1524 len = strlen(buf);
1525 if (len < 83 || buf[len-1] != '\n' ||
1526 get_sha1_hex(buf, osha1) || buf[40] != ' ' ||
1527 get_sha1_hex(buf + 41, nsha1) || buf[81] != ' ' ||
1528 !(email_end = strchr(buf + 82, '>')) ||
1529 email_end[1] != ' ' ||
1530 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1531 !message || message[0] != ' ' ||
1532 (message[1] != '+' && message[1] != '-') ||
1533 !isdigit(message[2]) || !isdigit(message[3]) ||
1534 !isdigit(message[4]) || !isdigit(message[5]))
1535 continue; /* corrupt? */
1536 email_end[1] = '\0';
1537 tz = strtol(message + 1, NULL, 10);
1538 if (message[6] != '\t')
1539 message += 6;
1540 else
1541 message += 7;
1542 ret = fn(osha1, nsha1, buf+82, timestamp, tz, message, cb_data);
1543 if (ret)
1544 break;
1545 }
1546 fclose(logfp);
1547 return ret;
1548 }
1549
1550 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1551 {
1552 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1553 }
1554
1555 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1556 {
1557 DIR *dir = opendir(git_path("logs/%s", base));
1558 int retval = 0;
1559
1560 if (dir) {
1561 struct dirent *de;
1562 int baselen = strlen(base);
1563 char *log = xmalloc(baselen + 257);
1564
1565 memcpy(log, base, baselen);
1566 if (baselen && base[baselen-1] != '/')
1567 log[baselen++] = '/';
1568
1569 while ((de = readdir(dir)) != NULL) {
1570 struct stat st;
1571 int namelen;
1572
1573 if (de->d_name[0] == '.')
1574 continue;
1575 namelen = strlen(de->d_name);
1576 if (namelen > 255)
1577 continue;
1578 if (has_extension(de->d_name, ".lock"))
1579 continue;
1580 memcpy(log + baselen, de->d_name, namelen+1);
1581 if (stat(git_path("logs/%s", log), &st) < 0)
1582 continue;
1583 if (S_ISDIR(st.st_mode)) {
1584 retval = do_for_each_reflog(log, fn, cb_data);
1585 } else {
1586 unsigned char sha1[20];
1587 if (!resolve_ref(log, sha1, 0, NULL))
1588 retval = error("bad ref for %s", log);
1589 else
1590 retval = fn(log, sha1, 0, cb_data);
1591 }
1592 if (retval)
1593 break;
1594 }
1595 free(log);
1596 closedir(dir);
1597 }
1598 else if (*base)
1599 return errno;
1600 return retval;
1601 }
1602
1603 int for_each_reflog(each_ref_fn fn, void *cb_data)
1604 {
1605 return do_for_each_reflog("", fn, cb_data);
1606 }
1607
1608 int update_ref(const char *action, const char *refname,
1609 const unsigned char *sha1, const unsigned char *oldval,
1610 int flags, enum action_on_err onerr)
1611 {
1612 static struct ref_lock *lock;
1613 lock = lock_any_ref_for_update(refname, oldval, flags);
1614 if (!lock) {
1615 const char *str = "Cannot lock the ref '%s'.";
1616 switch (onerr) {
1617 case MSG_ON_ERR: error(str, refname); break;
1618 case DIE_ON_ERR: die(str, refname); break;
1619 case QUIET_ON_ERR: break;
1620 }
1621 return 1;
1622 }
1623 if (write_ref_sha1(lock, sha1, action) < 0) {
1624 const char *str = "Cannot update the ref '%s'.";
1625 switch (onerr) {
1626 case MSG_ON_ERR: error(str, refname); break;
1627 case DIE_ON_ERR: die(str, refname); break;
1628 case QUIET_ON_ERR: break;
1629 }
1630 return 1;
1631 }
1632 return 0;
1633 }
1634
1635 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1636 {
1637 for ( ; list; list = list->next)
1638 if (!strcmp(list->name, name))
1639 return (struct ref *)list;
1640 return NULL;
1641 }