ee3e0cc560eafc1c32104fa439a070c00fdcc12a
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
11struct 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
19static 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
47static struct ref_list *add_ref(const char *name, const unsigned char *sha1,
48 int flag, struct ref_list *list,
49 struct ref_list **new_entry)
50{
51 int len;
52 struct ref_list *entry;
53
54 /* Allocate it and add it in.. */
55 len = strlen(name) + 1;
56 entry = xmalloc(sizeof(struct ref_list) + len);
57 hashcpy(entry->sha1, sha1);
58 hashclr(entry->peeled);
59 memcpy(entry->name, name, len);
60 entry->flag = flag;
61 entry->next = list;
62 if (new_entry)
63 *new_entry = entry;
64 return entry;
65}
66
67/* merge sort the ref list */
68static struct ref_list *sort_ref_list(struct ref_list *list)
69{
70 int psize, qsize, last_merge_count, cmp;
71 struct ref_list *p, *q, *l, *e;
72 struct ref_list *new_list = list;
73 int k = 1;
74 int merge_count = 0;
75
76 if (!list)
77 return list;
78
79 do {
80 last_merge_count = merge_count;
81 merge_count = 0;
82
83 psize = 0;
84
85 p = new_list;
86 q = new_list;
87 new_list = NULL;
88 l = NULL;
89
90 while (p) {
91 merge_count++;
92
93 while (psize < k && q->next) {
94 q = q->next;
95 psize++;
96 }
97 qsize = k;
98
99 while ((psize > 0) || (qsize > 0 && q)) {
100 if (qsize == 0 || !q) {
101 e = p;
102 p = p->next;
103 psize--;
104 } else if (psize == 0) {
105 e = q;
106 q = q->next;
107 qsize--;
108 } else {
109 cmp = strcmp(q->name, p->name);
110 if (cmp < 0) {
111 e = q;
112 q = q->next;
113 qsize--;
114 } else if (cmp > 0) {
115 e = p;
116 p = p->next;
117 psize--;
118 } else {
119 if (hashcmp(q->sha1, p->sha1))
120 die("Duplicated ref, and SHA1s don't match: %s",
121 q->name);
122 warning("Duplicated ref: %s", q->name);
123 e = q;
124 q = q->next;
125 qsize--;
126 free(e);
127 e = p;
128 p = p->next;
129 psize--;
130 }
131 }
132
133 e->next = NULL;
134
135 if (l)
136 l->next = e;
137 if (!new_list)
138 new_list = e;
139 l = e;
140 }
141
142 p = q;
143 };
144
145 k = k * 2;
146 } while ((last_merge_count != merge_count) || (last_merge_count != 1));
147
148 return new_list;
149}
150
151/*
152 * Future: need to be in "struct repository"
153 * when doing a full libification.
154 */
155static struct cached_refs {
156 char did_loose;
157 char did_packed;
158 struct ref_list *loose;
159 struct ref_list *packed;
160} cached_refs, submodule_refs;
161static struct ref_list *current_ref;
162
163static struct ref_list *extra_refs;
164
165static void free_ref_list(struct ref_list *list)
166{
167 struct ref_list *next;
168 for ( ; list; list = next) {
169 next = list->next;
170 free(list);
171 }
172}
173
174static void invalidate_cached_refs(void)
175{
176 struct cached_refs *ca = &cached_refs;
177
178 if (ca->did_loose && ca->loose)
179 free_ref_list(ca->loose);
180 if (ca->did_packed && ca->packed)
181 free_ref_list(ca->packed);
182 ca->loose = ca->packed = NULL;
183 ca->did_loose = ca->did_packed = 0;
184}
185
186static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
187{
188 struct ref_list *list = NULL;
189 struct ref_list *last = NULL;
190 char refline[PATH_MAX];
191 int flag = REF_ISPACKED;
192
193 while (fgets(refline, sizeof(refline), f)) {
194 unsigned char sha1[20];
195 const char *name;
196 static const char header[] = "# pack-refs with:";
197
198 if (!strncmp(refline, header, sizeof(header)-1)) {
199 const char *traits = refline + sizeof(header) - 1;
200 if (strstr(traits, " peeled "))
201 flag |= REF_KNOWS_PEELED;
202 /* perhaps other traits later as well */
203 continue;
204 }
205
206 name = parse_ref_line(refline, sha1);
207 if (name) {
208 list = add_ref(name, sha1, flag, list, &last);
209 continue;
210 }
211 if (last &&
212 refline[0] == '^' &&
213 strlen(refline) == 42 &&
214 refline[41] == '\n' &&
215 !get_sha1_hex(refline + 1, sha1))
216 hashcpy(last->peeled, sha1);
217 }
218 cached_refs->packed = sort_ref_list(list);
219}
220
221void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
222{
223 extra_refs = add_ref(name, sha1, flag, extra_refs, NULL);
224}
225
226void clear_extra_refs(void)
227{
228 free_ref_list(extra_refs);
229 extra_refs = NULL;
230}
231
232static struct ref_list *get_packed_refs(const char *submodule)
233{
234 const char *packed_refs_file;
235 struct cached_refs *refs;
236
237 if (submodule) {
238 packed_refs_file = git_path_submodule(submodule, "packed-refs");
239 refs = &submodule_refs;
240 free_ref_list(refs->packed);
241 } else {
242 packed_refs_file = git_path("packed-refs");
243 refs = &cached_refs;
244 }
245
246 if (!refs->did_packed || submodule) {
247 FILE *f = fopen(packed_refs_file, "r");
248 refs->packed = NULL;
249 if (f) {
250 read_packed_refs(f, refs);
251 fclose(f);
252 }
253 refs->did_packed = 1;
254 }
255 return refs->packed;
256}
257
258static struct ref_list *get_ref_dir(const char *submodule, const char *base,
259 struct ref_list *list)
260{
261 DIR *dir;
262 const char *path;
263
264 if (submodule)
265 path = git_path_submodule(submodule, "%s", base);
266 else
267 path = git_path("%s", base);
268
269
270 dir = opendir(path);
271
272 if (dir) {
273 struct dirent *de;
274 int baselen = strlen(base);
275 char *ref = xmalloc(baselen + 257);
276
277 memcpy(ref, base, baselen);
278 if (baselen && base[baselen-1] != '/')
279 ref[baselen++] = '/';
280
281 while ((de = readdir(dir)) != NULL) {
282 unsigned char sha1[20];
283 struct stat st;
284 int flag;
285 int namelen;
286 const char *refdir;
287
288 if (de->d_name[0] == '.')
289 continue;
290 namelen = strlen(de->d_name);
291 if (namelen > 255)
292 continue;
293 if (has_extension(de->d_name, ".lock"))
294 continue;
295 memcpy(ref + baselen, de->d_name, namelen+1);
296 refdir = submodule
297 ? git_path_submodule(submodule, "%s", ref)
298 : git_path("%s", ref);
299 if (stat(refdir, &st) < 0)
300 continue;
301 if (S_ISDIR(st.st_mode)) {
302 list = get_ref_dir(submodule, ref, list);
303 continue;
304 }
305 if (submodule) {
306 hashclr(sha1);
307 flag = 0;
308 if (resolve_gitlink_ref(submodule, ref, sha1) < 0) {
309 hashclr(sha1);
310 flag |= REF_BROKEN;
311 }
312 } else
313 if (!resolve_ref(ref, sha1, 1, &flag)) {
314 hashclr(sha1);
315 flag |= REF_BROKEN;
316 }
317 list = add_ref(ref, sha1, flag, list, NULL);
318 }
319 free(ref);
320 closedir(dir);
321 }
322 return sort_ref_list(list);
323}
324
325struct warn_if_dangling_data {
326 FILE *fp;
327 const char *refname;
328 const char *msg_fmt;
329};
330
331static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
332 int flags, void *cb_data)
333{
334 struct warn_if_dangling_data *d = cb_data;
335 const char *resolves_to;
336 unsigned char junk[20];
337
338 if (!(flags & REF_ISSYMREF))
339 return 0;
340
341 resolves_to = resolve_ref(refname, junk, 0, NULL);
342 if (!resolves_to || strcmp(resolves_to, d->refname))
343 return 0;
344
345 fprintf(d->fp, d->msg_fmt, refname);
346 return 0;
347}
348
349void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
350{
351 struct warn_if_dangling_data data;
352
353 data.fp = fp;
354 data.refname = refname;
355 data.msg_fmt = msg_fmt;
356 for_each_rawref(warn_if_dangling_symref, &data);
357}
358
359static struct ref_list *get_loose_refs(const char *submodule)
360{
361 if (submodule) {
362 free_ref_list(submodule_refs.loose);
363 submodule_refs.loose = get_ref_dir(submodule, "refs", NULL);
364 return submodule_refs.loose;
365 }
366
367 if (!cached_refs.did_loose) {
368 cached_refs.loose = get_ref_dir(NULL, "refs", NULL);
369 cached_refs.did_loose = 1;
370 }
371 return cached_refs.loose;
372}
373
374/* We allow "recursive" symbolic refs. Only within reason, though */
375#define MAXDEPTH 5
376#define MAXREFLEN (1024)
377
378static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
379{
380 FILE *f;
381 struct cached_refs refs;
382 struct ref_list *ref;
383 int retval;
384
385 strcpy(name + pathlen, "packed-refs");
386 f = fopen(name, "r");
387 if (!f)
388 return -1;
389 read_packed_refs(f, &refs);
390 fclose(f);
391 ref = refs.packed;
392 retval = -1;
393 while (ref) {
394 if (!strcmp(ref->name, refname)) {
395 retval = 0;
396 memcpy(result, ref->sha1, 20);
397 break;
398 }
399 ref = ref->next;
400 }
401 free_ref_list(refs.packed);
402 return retval;
403}
404
405static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
406{
407 int fd, len = strlen(refname);
408 char buffer[128], *p;
409
410 if (recursion > MAXDEPTH || len > MAXREFLEN)
411 return -1;
412 memcpy(name + pathlen, refname, len+1);
413 fd = open(name, O_RDONLY);
414 if (fd < 0)
415 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
416
417 len = read(fd, buffer, sizeof(buffer)-1);
418 close(fd);
419 if (len < 0)
420 return -1;
421 while (len && isspace(buffer[len-1]))
422 len--;
423 buffer[len] = 0;
424
425 /* Was it a detached head or an old-fashioned symlink? */
426 if (!get_sha1_hex(buffer, result))
427 return 0;
428
429 /* Symref? */
430 if (strncmp(buffer, "ref:", 4))
431 return -1;
432 p = buffer + 4;
433 while (isspace(*p))
434 p++;
435
436 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
437}
438
439int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
440{
441 int len = strlen(path), retval;
442 char *gitdir;
443 const char *tmp;
444
445 while (len && path[len-1] == '/')
446 len--;
447 if (!len)
448 return -1;
449 gitdir = xmalloc(len + MAXREFLEN + 8);
450 memcpy(gitdir, path, len);
451 memcpy(gitdir + len, "/.git", 6);
452 len += 5;
453
454 tmp = read_gitfile(gitdir);
455 if (tmp) {
456 free(gitdir);
457 len = strlen(tmp);
458 gitdir = xmalloc(len + MAXREFLEN + 3);
459 memcpy(gitdir, tmp, len);
460 }
461 gitdir[len] = '/';
462 gitdir[++len] = '\0';
463 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
464 free(gitdir);
465 return retval;
466}
467
468/*
469 * Try to read ref from the packed references. On success, set sha1
470 * and return 0; otherwise, return -1.
471 */
472static int get_packed_ref(const char *ref, unsigned char *sha1)
473{
474 struct ref_list *list = get_packed_refs(NULL);
475 while (list) {
476 if (!strcmp(ref, list->name)) {
477 hashcpy(sha1, list->sha1);
478 return 0;
479 }
480 list = list->next;
481 }
482 return -1;
483}
484
485/*
486 * If the "reading" argument is set, this function finds out what _object_
487 * the ref points at by "reading" the ref. The ref, if it is not symbolic,
488 * has to exist, and if it is symbolic, it has to point at an existing ref,
489 * because the "read" goes through the symref to the ref it points at.
490 *
491 * The access that is not "reading" may often be "writing", but does not
492 * have to; it can be merely checking _where it leads to_. If it is a
493 * prelude to "writing" to the ref, a write to a symref that points at
494 * yet-to-be-born ref will create the real ref pointed by the symref.
495 * reading=0 allows the caller to check where such a symref leads to.
496 */
497const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
498{
499 int depth = MAXDEPTH;
500 ssize_t len;
501 char buffer[256];
502 static char ref_buffer[256];
503
504 if (flag)
505 *flag = 0;
506
507 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
508 return NULL;
509
510 for (;;) {
511 char path[PATH_MAX];
512 struct stat st;
513 char *buf;
514 int fd;
515
516 if (--depth < 0)
517 return NULL;
518
519 git_snpath(path, sizeof(path), "%s", ref);
520
521 if (lstat(path, &st) < 0) {
522 if (errno != ENOENT)
523 return NULL;
524 /*
525 * The loose reference file does not exist;
526 * check for a packed reference.
527 */
528 if (!get_packed_ref(ref, sha1)) {
529 if (flag)
530 *flag |= REF_ISPACKED;
531 return ref;
532 }
533 /* The reference is not a packed reference, either. */
534 if (reading) {
535 return NULL;
536 } else {
537 hashclr(sha1);
538 return ref;
539 }
540 }
541
542 /* Follow "normalized" - ie "refs/.." symlinks by hand */
543 if (S_ISLNK(st.st_mode)) {
544 len = readlink(path, buffer, sizeof(buffer)-1);
545 if (len < 0)
546 return NULL;
547 buffer[len] = 0;
548 if (!prefixcmp(buffer, "refs/") &&
549 !check_refname_format(buffer, 0)) {
550 strcpy(ref_buffer, buffer);
551 ref = ref_buffer;
552 if (flag)
553 *flag |= REF_ISSYMREF;
554 continue;
555 }
556 }
557
558 /* Is it a directory? */
559 if (S_ISDIR(st.st_mode)) {
560 errno = EISDIR;
561 return NULL;
562 }
563
564 /*
565 * Anything else, just open it and try to use it as
566 * a ref
567 */
568 fd = open(path, O_RDONLY);
569 if (fd < 0)
570 return NULL;
571 len = read_in_full(fd, buffer, sizeof(buffer)-1);
572 close(fd);
573 if (len < 0)
574 return NULL;
575 while (len && isspace(buffer[len-1]))
576 len--;
577 buffer[len] = '\0';
578
579 /*
580 * Is it a symbolic ref?
581 */
582 if (prefixcmp(buffer, "ref:"))
583 break;
584 buf = buffer + 4;
585 while (isspace(*buf))
586 buf++;
587 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
588 warning("symbolic reference in %s is formatted incorrectly",
589 path);
590 return NULL;
591 }
592 ref = strcpy(ref_buffer, buf);
593 if (flag)
594 *flag |= REF_ISSYMREF;
595 }
596 if (get_sha1_hex(buffer, sha1))
597 return NULL;
598 return ref;
599}
600
601/* The argument to filter_refs */
602struct ref_filter {
603 const char *pattern;
604 each_ref_fn *fn;
605 void *cb_data;
606};
607
608int read_ref(const char *ref, unsigned char *sha1)
609{
610 if (resolve_ref(ref, sha1, 1, NULL))
611 return 0;
612 return -1;
613}
614
615#define DO_FOR_EACH_INCLUDE_BROKEN 01
616static int do_one_ref(const char *base, each_ref_fn fn, int trim,
617 int flags, void *cb_data, struct ref_list *entry)
618{
619 if (prefixcmp(entry->name, base))
620 return 0;
621
622 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
623 if (entry->flag & REF_BROKEN)
624 return 0; /* ignore dangling symref */
625 if (!has_sha1_file(entry->sha1)) {
626 error("%s does not point to a valid object!", entry->name);
627 return 0;
628 }
629 }
630 current_ref = entry;
631 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
632}
633
634static int filter_refs(const char *ref, const unsigned char *sha, int flags,
635 void *data)
636{
637 struct ref_filter *filter = (struct ref_filter *)data;
638 if (fnmatch(filter->pattern, ref, 0))
639 return 0;
640 return filter->fn(ref, sha, flags, filter->cb_data);
641}
642
643int peel_ref(const char *ref, unsigned char *sha1)
644{
645 int flag;
646 unsigned char base[20];
647 struct object *o;
648
649 if (current_ref && (current_ref->name == ref
650 || !strcmp(current_ref->name, ref))) {
651 if (current_ref->flag & REF_KNOWS_PEELED) {
652 hashcpy(sha1, current_ref->peeled);
653 return 0;
654 }
655 hashcpy(base, current_ref->sha1);
656 goto fallback;
657 }
658
659 if (!resolve_ref(ref, base, 1, &flag))
660 return -1;
661
662 if ((flag & REF_ISPACKED)) {
663 struct ref_list *list = get_packed_refs(NULL);
664
665 while (list) {
666 if (!strcmp(list->name, ref)) {
667 if (list->flag & REF_KNOWS_PEELED) {
668 hashcpy(sha1, list->peeled);
669 return 0;
670 }
671 /* older pack-refs did not leave peeled ones */
672 break;
673 }
674 list = list->next;
675 }
676 }
677
678fallback:
679 o = parse_object(base);
680 if (o && o->type == OBJ_TAG) {
681 o = deref_tag(o, ref, 0);
682 if (o) {
683 hashcpy(sha1, o->sha1);
684 return 0;
685 }
686 }
687 return -1;
688}
689
690static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
691 int trim, int flags, void *cb_data)
692{
693 int retval = 0;
694 struct ref_list *packed = get_packed_refs(submodule);
695 struct ref_list *loose = get_loose_refs(submodule);
696
697 struct ref_list *extra;
698
699 for (extra = extra_refs; extra; extra = extra->next)
700 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
701
702 while (packed && loose) {
703 struct ref_list *entry;
704 int cmp = strcmp(packed->name, loose->name);
705 if (!cmp) {
706 packed = packed->next;
707 continue;
708 }
709 if (cmp > 0) {
710 entry = loose;
711 loose = loose->next;
712 } else {
713 entry = packed;
714 packed = packed->next;
715 }
716 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
717 if (retval)
718 goto end_each;
719 }
720
721 for (packed = packed ? packed : loose; packed; packed = packed->next) {
722 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
723 if (retval)
724 goto end_each;
725 }
726
727end_each:
728 current_ref = NULL;
729 return retval;
730}
731
732
733static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
734{
735 unsigned char sha1[20];
736 int flag;
737
738 if (submodule) {
739 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
740 return fn("HEAD", sha1, 0, cb_data);
741
742 return 0;
743 }
744
745 if (resolve_ref("HEAD", sha1, 1, &flag))
746 return fn("HEAD", sha1, flag, cb_data);
747
748 return 0;
749}
750
751int head_ref(each_ref_fn fn, void *cb_data)
752{
753 return do_head_ref(NULL, fn, cb_data);
754}
755
756int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
757{
758 return do_head_ref(submodule, fn, cb_data);
759}
760
761int for_each_ref(each_ref_fn fn, void *cb_data)
762{
763 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
764}
765
766int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
767{
768 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
769}
770
771int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
772{
773 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
774}
775
776int for_each_ref_in_submodule(const char *submodule, const char *prefix,
777 each_ref_fn fn, void *cb_data)
778{
779 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
780}
781
782int for_each_tag_ref(each_ref_fn fn, void *cb_data)
783{
784 return for_each_ref_in("refs/tags/", fn, cb_data);
785}
786
787int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
788{
789 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
790}
791
792int for_each_branch_ref(each_ref_fn fn, void *cb_data)
793{
794 return for_each_ref_in("refs/heads/", fn, cb_data);
795}
796
797int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
798{
799 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
800}
801
802int for_each_remote_ref(each_ref_fn fn, void *cb_data)
803{
804 return for_each_ref_in("refs/remotes/", fn, cb_data);
805}
806
807int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
808{
809 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
810}
811
812int for_each_replace_ref(each_ref_fn fn, void *cb_data)
813{
814 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
815}
816
817int head_ref_namespaced(each_ref_fn fn, void *cb_data)
818{
819 struct strbuf buf = STRBUF_INIT;
820 int ret = 0;
821 unsigned char sha1[20];
822 int flag;
823
824 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
825 if (resolve_ref(buf.buf, sha1, 1, &flag))
826 ret = fn(buf.buf, sha1, flag, cb_data);
827 strbuf_release(&buf);
828
829 return ret;
830}
831
832int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
833{
834 struct strbuf buf = STRBUF_INIT;
835 int ret;
836 strbuf_addf(&buf, "%srefs/", get_git_namespace());
837 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
838 strbuf_release(&buf);
839 return ret;
840}
841
842int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
843 const char *prefix, void *cb_data)
844{
845 struct strbuf real_pattern = STRBUF_INIT;
846 struct ref_filter filter;
847 int ret;
848
849 if (!prefix && prefixcmp(pattern, "refs/"))
850 strbuf_addstr(&real_pattern, "refs/");
851 else if (prefix)
852 strbuf_addstr(&real_pattern, prefix);
853 strbuf_addstr(&real_pattern, pattern);
854
855 if (!has_glob_specials(pattern)) {
856 /* Append implied '/' '*' if not present. */
857 if (real_pattern.buf[real_pattern.len - 1] != '/')
858 strbuf_addch(&real_pattern, '/');
859 /* No need to check for '*', there is none. */
860 strbuf_addch(&real_pattern, '*');
861 }
862
863 filter.pattern = real_pattern.buf;
864 filter.fn = fn;
865 filter.cb_data = cb_data;
866 ret = for_each_ref(filter_refs, &filter);
867
868 strbuf_release(&real_pattern);
869 return ret;
870}
871
872int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
873{
874 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
875}
876
877int for_each_rawref(each_ref_fn fn, void *cb_data)
878{
879 return do_for_each_ref(NULL, "", fn, 0,
880 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
881}
882
883/*
884 * Make sure "ref" is something reasonable to have under ".git/refs/";
885 * We do not like it if:
886 *
887 * - any path component of it begins with ".", or
888 * - it has double dots "..", or
889 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
890 * - it ends with a "/".
891 * - it ends with ".lock"
892 * - it contains a "\" (backslash)
893 */
894
895/* Return true iff ch is not allowed in reference names. */
896static inline int bad_ref_char(int ch)
897{
898 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
899 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
900 return 1;
901 /* 2.13 Pattern Matching Notation */
902 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
903 return 1;
904 return 0;
905}
906
907/*
908 * Try to read one refname component from the front of ref. Return
909 * the length of the component found, or -1 if the component is not
910 * legal.
911 */
912static int check_refname_component(const char *ref)
913{
914 const char *cp;
915 char last = '\0';
916
917 for (cp = ref; ; cp++) {
918 char ch = *cp;
919 if (ch == '\0' || ch == '/')
920 break;
921 if (bad_ref_char(ch))
922 return -1; /* Illegal character in refname. */
923 if (last == '.' && ch == '.')
924 return -1; /* Refname contains "..". */
925 if (last == '@' && ch == '{')
926 return -1; /* Refname contains "@{". */
927 last = ch;
928 }
929 if (cp == ref)
930 return -1; /* Component has zero length. */
931 if (ref[0] == '.')
932 return -1; /* Component starts with '.'. */
933 if (cp - ref >= 5 && !memcmp(cp - 5, ".lock", 5))
934 return -1; /* Refname ends with ".lock". */
935 return cp - ref;
936}
937
938int check_refname_format(const char *ref, int flags)
939{
940 int component_len, component_count = 0;
941
942 while (1) {
943 /* We are at the start of a path component. */
944 component_len = check_refname_component(ref);
945 if (component_len < 0) {
946 if ((flags & REFNAME_REFSPEC_PATTERN) &&
947 ref[0] == '*' &&
948 (ref[1] == '\0' || ref[1] == '/')) {
949 /* Accept one wildcard as a full refname component. */
950 flags &= ~REFNAME_REFSPEC_PATTERN;
951 component_len = 1;
952 } else {
953 return -1;
954 }
955 }
956 component_count++;
957 if (ref[component_len] == '\0')
958 break;
959 /* Skip to next component. */
960 ref += component_len + 1;
961 }
962
963 if (ref[component_len - 1] == '.')
964 return -1; /* Refname ends with '.'. */
965 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
966 return -1; /* Refname has only one component. */
967 return 0;
968}
969
970const char *prettify_refname(const char *name)
971{
972 return name + (
973 !prefixcmp(name, "refs/heads/") ? 11 :
974 !prefixcmp(name, "refs/tags/") ? 10 :
975 !prefixcmp(name, "refs/remotes/") ? 13 :
976 0);
977}
978
979const char *ref_rev_parse_rules[] = {
980 "%.*s",
981 "refs/%.*s",
982 "refs/tags/%.*s",
983 "refs/heads/%.*s",
984 "refs/remotes/%.*s",
985 "refs/remotes/%.*s/HEAD",
986 NULL
987};
988
989const char *ref_fetch_rules[] = {
990 "%.*s",
991 "refs/%.*s",
992 "refs/heads/%.*s",
993 NULL
994};
995
996int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
997{
998 const char **p;
999 const int abbrev_name_len = strlen(abbrev_name);
1000
1001 for (p = rules; *p; p++) {
1002 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1003 return 1;
1004 }
1005 }
1006
1007 return 0;
1008}
1009
1010static struct ref_lock *verify_lock(struct ref_lock *lock,
1011 const unsigned char *old_sha1, int mustexist)
1012{
1013 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
1014 error("Can't verify ref %s", lock->ref_name);
1015 unlock_ref(lock);
1016 return NULL;
1017 }
1018 if (hashcmp(lock->old_sha1, old_sha1)) {
1019 error("Ref %s is at %s but expected %s", lock->ref_name,
1020 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1021 unlock_ref(lock);
1022 return NULL;
1023 }
1024 return lock;
1025}
1026
1027static int remove_empty_directories(const char *file)
1028{
1029 /* we want to create a file but there is a directory there;
1030 * if that is an empty directory (or a directory that contains
1031 * only empty directories), remove them.
1032 */
1033 struct strbuf path;
1034 int result;
1035
1036 strbuf_init(&path, 20);
1037 strbuf_addstr(&path, file);
1038
1039 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1040
1041 strbuf_release(&path);
1042
1043 return result;
1044}
1045
1046static int is_refname_available(const char *ref, const char *oldref,
1047 struct ref_list *list, int quiet)
1048{
1049 int namlen = strlen(ref); /* e.g. 'foo/bar' */
1050 while (list) {
1051 /* list->name could be 'foo' or 'foo/bar/baz' */
1052 if (!oldref || strcmp(oldref, list->name)) {
1053 int len = strlen(list->name);
1054 int cmplen = (namlen < len) ? namlen : len;
1055 const char *lead = (namlen < len) ? list->name : ref;
1056 if (!strncmp(ref, list->name, cmplen) &&
1057 lead[cmplen] == '/') {
1058 if (!quiet)
1059 error("'%s' exists; cannot create '%s'",
1060 list->name, ref);
1061 return 0;
1062 }
1063 }
1064 list = list->next;
1065 }
1066 return 1;
1067}
1068
1069static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
1070{
1071 char *ref_file;
1072 const char *orig_ref = ref;
1073 struct ref_lock *lock;
1074 int last_errno = 0;
1075 int type, lflags;
1076 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1077 int missing = 0;
1078
1079 lock = xcalloc(1, sizeof(struct ref_lock));
1080 lock->lock_fd = -1;
1081
1082 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
1083 if (!ref && errno == EISDIR) {
1084 /* we are trying to lock foo but we used to
1085 * have foo/bar which now does not exist;
1086 * it is normal for the empty directory 'foo'
1087 * to remain.
1088 */
1089 ref_file = git_path("%s", orig_ref);
1090 if (remove_empty_directories(ref_file)) {
1091 last_errno = errno;
1092 error("there are still refs under '%s'", orig_ref);
1093 goto error_return;
1094 }
1095 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
1096 }
1097 if (type_p)
1098 *type_p = type;
1099 if (!ref) {
1100 last_errno = errno;
1101 error("unable to resolve reference %s: %s",
1102 orig_ref, strerror(errno));
1103 goto error_return;
1104 }
1105 missing = is_null_sha1(lock->old_sha1);
1106 /* When the ref did not exist and we are creating it,
1107 * make sure there is no existing ref that is packed
1108 * whose name begins with our refname, nor a ref whose
1109 * name is a proper prefix of our refname.
1110 */
1111 if (missing &&
1112 !is_refname_available(ref, NULL, get_packed_refs(NULL), 0)) {
1113 last_errno = ENOTDIR;
1114 goto error_return;
1115 }
1116
1117 lock->lk = xcalloc(1, sizeof(struct lock_file));
1118
1119 lflags = LOCK_DIE_ON_ERROR;
1120 if (flags & REF_NODEREF) {
1121 ref = orig_ref;
1122 lflags |= LOCK_NODEREF;
1123 }
1124 lock->ref_name = xstrdup(ref);
1125 lock->orig_ref_name = xstrdup(orig_ref);
1126 ref_file = git_path("%s", ref);
1127 if (missing)
1128 lock->force_write = 1;
1129 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1130 lock->force_write = 1;
1131
1132 if (safe_create_leading_directories(ref_file)) {
1133 last_errno = errno;
1134 error("unable to create directory for %s", ref_file);
1135 goto error_return;
1136 }
1137
1138 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1139 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1140
1141 error_return:
1142 unlock_ref(lock);
1143 errno = last_errno;
1144 return NULL;
1145}
1146
1147struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
1148{
1149 char refpath[PATH_MAX];
1150 if (check_refname_format(ref, 0))
1151 return NULL;
1152 strcpy(refpath, mkpath("refs/%s", ref));
1153 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1154}
1155
1156struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
1157{
1158 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
1159 return NULL;
1160 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1161}
1162
1163static struct lock_file packlock;
1164
1165static int repack_without_ref(const char *refname)
1166{
1167 struct ref_list *list, *packed_ref_list;
1168 int fd;
1169 int found = 0;
1170
1171 packed_ref_list = get_packed_refs(NULL);
1172 for (list = packed_ref_list; list; list = list->next) {
1173 if (!strcmp(refname, list->name)) {
1174 found = 1;
1175 break;
1176 }
1177 }
1178 if (!found)
1179 return 0;
1180 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1181 if (fd < 0) {
1182 unable_to_lock_error(git_path("packed-refs"), errno);
1183 return error("cannot delete '%s' from packed refs", refname);
1184 }
1185
1186 for (list = packed_ref_list; list; list = list->next) {
1187 char line[PATH_MAX + 100];
1188 int len;
1189
1190 if (!strcmp(refname, list->name))
1191 continue;
1192 len = snprintf(line, sizeof(line), "%s %s\n",
1193 sha1_to_hex(list->sha1), list->name);
1194 /* this should not happen but just being defensive */
1195 if (len > sizeof(line))
1196 die("too long a refname '%s'", list->name);
1197 write_or_die(fd, line, len);
1198 }
1199 return commit_lock_file(&packlock);
1200}
1201
1202int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1203{
1204 struct ref_lock *lock;
1205 int err, i = 0, ret = 0, flag = 0;
1206
1207 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1208 if (!lock)
1209 return 1;
1210 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1211 /* loose */
1212 const char *path;
1213
1214 if (!(delopt & REF_NODEREF)) {
1215 i = strlen(lock->lk->filename) - 5; /* .lock */
1216 lock->lk->filename[i] = 0;
1217 path = lock->lk->filename;
1218 } else {
1219 path = git_path("%s", refname);
1220 }
1221 err = unlink_or_warn(path);
1222 if (err && errno != ENOENT)
1223 ret = 1;
1224
1225 if (!(delopt & REF_NODEREF))
1226 lock->lk->filename[i] = '.';
1227 }
1228 /* removing the loose one could have resurrected an earlier
1229 * packed one. Also, if it was not loose we need to repack
1230 * without it.
1231 */
1232 ret |= repack_without_ref(refname);
1233
1234 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1235 invalidate_cached_refs();
1236 unlock_ref(lock);
1237 return ret;
1238}
1239
1240/*
1241 * People using contrib's git-new-workdir have .git/logs/refs ->
1242 * /some/other/path/.git/logs/refs, and that may live on another device.
1243 *
1244 * IOW, to avoid cross device rename errors, the temporary renamed log must
1245 * live into logs/refs.
1246 */
1247#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1248
1249int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1250{
1251 static const char renamed_ref[] = "RENAMED-REF";
1252 unsigned char sha1[20], orig_sha1[20];
1253 int flag = 0, logmoved = 0;
1254 struct ref_lock *lock;
1255 struct stat loginfo;
1256 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1257 const char *symref = NULL;
1258
1259 if (log && S_ISLNK(loginfo.st_mode))
1260 return error("reflog for %s is a symlink", oldref);
1261
1262 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1263 if (flag & REF_ISSYMREF)
1264 return error("refname %s is a symbolic ref, renaming it is not supported",
1265 oldref);
1266 if (!symref)
1267 return error("refname %s not found", oldref);
1268
1269 if (!is_refname_available(newref, oldref, get_packed_refs(NULL), 0))
1270 return 1;
1271
1272 if (!is_refname_available(newref, oldref, get_loose_refs(NULL), 0))
1273 return 1;
1274
1275 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
1276 if (!lock)
1277 return error("unable to lock %s", renamed_ref);
1278 lock->force_write = 1;
1279 if (write_ref_sha1(lock, orig_sha1, logmsg))
1280 return error("unable to save current sha1 in %s", renamed_ref);
1281
1282 if (log && rename(git_path("logs/%s", oldref), git_path(TMP_RENAMED_LOG)))
1283 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1284 oldref, strerror(errno));
1285
1286 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1287 error("unable to delete old %s", oldref);
1288 goto rollback;
1289 }
1290
1291 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1292 if (errno==EISDIR) {
1293 if (remove_empty_directories(git_path("%s", newref))) {
1294 error("Directory not empty: %s", newref);
1295 goto rollback;
1296 }
1297 } else {
1298 error("unable to delete existing %s", newref);
1299 goto rollback;
1300 }
1301 }
1302
1303 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1304 error("unable to create directory for %s", newref);
1305 goto rollback;
1306 }
1307
1308 retry:
1309 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newref))) {
1310 if (errno==EISDIR || errno==ENOTDIR) {
1311 /*
1312 * rename(a, b) when b is an existing
1313 * directory ought to result in ISDIR, but
1314 * Solaris 5.8 gives ENOTDIR. Sheesh.
1315 */
1316 if (remove_empty_directories(git_path("logs/%s", newref))) {
1317 error("Directory not empty: logs/%s", newref);
1318 goto rollback;
1319 }
1320 goto retry;
1321 } else {
1322 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1323 newref, strerror(errno));
1324 goto rollback;
1325 }
1326 }
1327 logmoved = log;
1328
1329 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1330 if (!lock) {
1331 error("unable to lock %s for update", newref);
1332 goto rollback;
1333 }
1334 lock->force_write = 1;
1335 hashcpy(lock->old_sha1, orig_sha1);
1336 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1337 error("unable to write current sha1 into %s", newref);
1338 goto rollback;
1339 }
1340
1341 return 0;
1342
1343 rollback:
1344 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1345 if (!lock) {
1346 error("unable to lock %s for rollback", oldref);
1347 goto rollbacklog;
1348 }
1349
1350 lock->force_write = 1;
1351 flag = log_all_ref_updates;
1352 log_all_ref_updates = 0;
1353 if (write_ref_sha1(lock, orig_sha1, NULL))
1354 error("unable to write current sha1 into %s", oldref);
1355 log_all_ref_updates = flag;
1356
1357 rollbacklog:
1358 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1359 error("unable to restore logfile %s from %s: %s",
1360 oldref, newref, strerror(errno));
1361 if (!logmoved && log &&
1362 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldref)))
1363 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1364 oldref, strerror(errno));
1365
1366 return 1;
1367}
1368
1369int close_ref(struct ref_lock *lock)
1370{
1371 if (close_lock_file(lock->lk))
1372 return -1;
1373 lock->lock_fd = -1;
1374 return 0;
1375}
1376
1377int commit_ref(struct ref_lock *lock)
1378{
1379 if (commit_lock_file(lock->lk))
1380 return -1;
1381 lock->lock_fd = -1;
1382 return 0;
1383}
1384
1385void unlock_ref(struct ref_lock *lock)
1386{
1387 /* Do not free lock->lk -- atexit() still looks at them */
1388 if (lock->lk)
1389 rollback_lock_file(lock->lk);
1390 free(lock->ref_name);
1391 free(lock->orig_ref_name);
1392 free(lock);
1393}
1394
1395/*
1396 * copy the reflog message msg to buf, which has been allocated sufficiently
1397 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1398 * because reflog file is one line per entry.
1399 */
1400static int copy_msg(char *buf, const char *msg)
1401{
1402 char *cp = buf;
1403 char c;
1404 int wasspace = 1;
1405
1406 *cp++ = '\t';
1407 while ((c = *msg++)) {
1408 if (wasspace && isspace(c))
1409 continue;
1410 wasspace = isspace(c);
1411 if (wasspace)
1412 c = ' ';
1413 *cp++ = c;
1414 }
1415 while (buf < cp && isspace(cp[-1]))
1416 cp--;
1417 *cp++ = '\n';
1418 return cp - buf;
1419}
1420
1421int log_ref_setup(const char *ref_name, char *logfile, int bufsize)
1422{
1423 int logfd, oflags = O_APPEND | O_WRONLY;
1424
1425 git_snpath(logfile, bufsize, "logs/%s", ref_name);
1426 if (log_all_ref_updates &&
1427 (!prefixcmp(ref_name, "refs/heads/") ||
1428 !prefixcmp(ref_name, "refs/remotes/") ||
1429 !prefixcmp(ref_name, "refs/notes/") ||
1430 !strcmp(ref_name, "HEAD"))) {
1431 if (safe_create_leading_directories(logfile) < 0)
1432 return error("unable to create directory for %s",
1433 logfile);
1434 oflags |= O_CREAT;
1435 }
1436
1437 logfd = open(logfile, oflags, 0666);
1438 if (logfd < 0) {
1439 if (!(oflags & O_CREAT) && errno == ENOENT)
1440 return 0;
1441
1442 if ((oflags & O_CREAT) && errno == EISDIR) {
1443 if (remove_empty_directories(logfile)) {
1444 return error("There are still logs under '%s'",
1445 logfile);
1446 }
1447 logfd = open(logfile, oflags, 0666);
1448 }
1449
1450 if (logfd < 0)
1451 return error("Unable to append to %s: %s",
1452 logfile, strerror(errno));
1453 }
1454
1455 adjust_shared_perm(logfile);
1456 close(logfd);
1457 return 0;
1458}
1459
1460static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1461 const unsigned char *new_sha1, const char *msg)
1462{
1463 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1464 unsigned maxlen, len;
1465 int msglen;
1466 char log_file[PATH_MAX];
1467 char *logrec;
1468 const char *committer;
1469
1470 if (log_all_ref_updates < 0)
1471 log_all_ref_updates = !is_bare_repository();
1472
1473 result = log_ref_setup(ref_name, log_file, sizeof(log_file));
1474 if (result)
1475 return result;
1476
1477 logfd = open(log_file, oflags);
1478 if (logfd < 0)
1479 return 0;
1480 msglen = msg ? strlen(msg) : 0;
1481 committer = git_committer_info(0);
1482 maxlen = strlen(committer) + msglen + 100;
1483 logrec = xmalloc(maxlen);
1484 len = sprintf(logrec, "%s %s %s\n",
1485 sha1_to_hex(old_sha1),
1486 sha1_to_hex(new_sha1),
1487 committer);
1488 if (msglen)
1489 len += copy_msg(logrec + len - 1, msg) - 1;
1490 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1491 free(logrec);
1492 if (close(logfd) != 0 || written != len)
1493 return error("Unable to append to %s", log_file);
1494 return 0;
1495}
1496
1497static int is_branch(const char *refname)
1498{
1499 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1500}
1501
1502int write_ref_sha1(struct ref_lock *lock,
1503 const unsigned char *sha1, const char *logmsg)
1504{
1505 static char term = '\n';
1506 struct object *o;
1507
1508 if (!lock)
1509 return -1;
1510 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1511 unlock_ref(lock);
1512 return 0;
1513 }
1514 o = parse_object(sha1);
1515 if (!o) {
1516 error("Trying to write ref %s with nonexistent object %s",
1517 lock->ref_name, sha1_to_hex(sha1));
1518 unlock_ref(lock);
1519 return -1;
1520 }
1521 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1522 error("Trying to write non-commit object %s to branch %s",
1523 sha1_to_hex(sha1), lock->ref_name);
1524 unlock_ref(lock);
1525 return -1;
1526 }
1527 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1528 write_in_full(lock->lock_fd, &term, 1) != 1
1529 || close_ref(lock) < 0) {
1530 error("Couldn't write %s", lock->lk->filename);
1531 unlock_ref(lock);
1532 return -1;
1533 }
1534 invalidate_cached_refs();
1535 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1536 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1537 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1538 unlock_ref(lock);
1539 return -1;
1540 }
1541 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1542 /*
1543 * Special hack: If a branch is updated directly and HEAD
1544 * points to it (may happen on the remote side of a push
1545 * for example) then logically the HEAD reflog should be
1546 * updated too.
1547 * A generic solution implies reverse symref information,
1548 * but finding all symrefs pointing to the given branch
1549 * would be rather costly for this rare event (the direct
1550 * update of a branch) to be worth it. So let's cheat and
1551 * check with HEAD only which should cover 99% of all usage
1552 * scenarios (even 100% of the default ones).
1553 */
1554 unsigned char head_sha1[20];
1555 int head_flag;
1556 const char *head_ref;
1557 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1558 if (head_ref && (head_flag & REF_ISSYMREF) &&
1559 !strcmp(head_ref, lock->ref_name))
1560 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1561 }
1562 if (commit_ref(lock)) {
1563 error("Couldn't set %s", lock->ref_name);
1564 unlock_ref(lock);
1565 return -1;
1566 }
1567 unlock_ref(lock);
1568 return 0;
1569}
1570
1571int create_symref(const char *ref_target, const char *refs_heads_master,
1572 const char *logmsg)
1573{
1574 const char *lockpath;
1575 char ref[1000];
1576 int fd, len, written;
1577 char *git_HEAD = git_pathdup("%s", ref_target);
1578 unsigned char old_sha1[20], new_sha1[20];
1579
1580 if (logmsg && read_ref(ref_target, old_sha1))
1581 hashclr(old_sha1);
1582
1583 if (safe_create_leading_directories(git_HEAD) < 0)
1584 return error("unable to create directory for %s", git_HEAD);
1585
1586#ifndef NO_SYMLINK_HEAD
1587 if (prefer_symlink_refs) {
1588 unlink(git_HEAD);
1589 if (!symlink(refs_heads_master, git_HEAD))
1590 goto done;
1591 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1592 }
1593#endif
1594
1595 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1596 if (sizeof(ref) <= len) {
1597 error("refname too long: %s", refs_heads_master);
1598 goto error_free_return;
1599 }
1600 lockpath = mkpath("%s.lock", git_HEAD);
1601 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1602 if (fd < 0) {
1603 error("Unable to open %s for writing", lockpath);
1604 goto error_free_return;
1605 }
1606 written = write_in_full(fd, ref, len);
1607 if (close(fd) != 0 || written != len) {
1608 error("Unable to write to %s", lockpath);
1609 goto error_unlink_return;
1610 }
1611 if (rename(lockpath, git_HEAD) < 0) {
1612 error("Unable to create %s", git_HEAD);
1613 goto error_unlink_return;
1614 }
1615 if (adjust_shared_perm(git_HEAD)) {
1616 error("Unable to fix permissions on %s", lockpath);
1617 error_unlink_return:
1618 unlink_or_warn(lockpath);
1619 error_free_return:
1620 free(git_HEAD);
1621 return -1;
1622 }
1623
1624#ifndef NO_SYMLINK_HEAD
1625 done:
1626#endif
1627 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1628 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1629
1630 free(git_HEAD);
1631 return 0;
1632}
1633
1634static char *ref_msg(const char *line, const char *endp)
1635{
1636 const char *ep;
1637 line += 82;
1638 ep = memchr(line, '\n', endp - line);
1639 if (!ep)
1640 ep = endp;
1641 return xmemdupz(line, ep - line);
1642}
1643
1644int 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)
1645{
1646 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1647 char *tz_c;
1648 int logfd, tz, reccnt = 0;
1649 struct stat st;
1650 unsigned long date;
1651 unsigned char logged_sha1[20];
1652 void *log_mapped;
1653 size_t mapsz;
1654
1655 logfile = git_path("logs/%s", ref);
1656 logfd = open(logfile, O_RDONLY, 0);
1657 if (logfd < 0)
1658 die_errno("Unable to read log '%s'", logfile);
1659 fstat(logfd, &st);
1660 if (!st.st_size)
1661 die("Log %s is empty.", logfile);
1662 mapsz = xsize_t(st.st_size);
1663 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1664 logdata = log_mapped;
1665 close(logfd);
1666
1667 lastrec = NULL;
1668 rec = logend = logdata + st.st_size;
1669 while (logdata < rec) {
1670 reccnt++;
1671 if (logdata < rec && *(rec-1) == '\n')
1672 rec--;
1673 lastgt = NULL;
1674 while (logdata < rec && *(rec-1) != '\n') {
1675 rec--;
1676 if (*rec == '>')
1677 lastgt = rec;
1678 }
1679 if (!lastgt)
1680 die("Log %s is corrupt.", logfile);
1681 date = strtoul(lastgt + 1, &tz_c, 10);
1682 if (date <= at_time || cnt == 0) {
1683 tz = strtoul(tz_c, NULL, 10);
1684 if (msg)
1685 *msg = ref_msg(rec, logend);
1686 if (cutoff_time)
1687 *cutoff_time = date;
1688 if (cutoff_tz)
1689 *cutoff_tz = tz;
1690 if (cutoff_cnt)
1691 *cutoff_cnt = reccnt - 1;
1692 if (lastrec) {
1693 if (get_sha1_hex(lastrec, logged_sha1))
1694 die("Log %s is corrupt.", logfile);
1695 if (get_sha1_hex(rec + 41, sha1))
1696 die("Log %s is corrupt.", logfile);
1697 if (hashcmp(logged_sha1, sha1)) {
1698 warning("Log %s has gap after %s.",
1699 logfile, show_date(date, tz, DATE_RFC2822));
1700 }
1701 }
1702 else if (date == at_time) {
1703 if (get_sha1_hex(rec + 41, sha1))
1704 die("Log %s is corrupt.", logfile);
1705 }
1706 else {
1707 if (get_sha1_hex(rec + 41, logged_sha1))
1708 die("Log %s is corrupt.", logfile);
1709 if (hashcmp(logged_sha1, sha1)) {
1710 warning("Log %s unexpectedly ended on %s.",
1711 logfile, show_date(date, tz, DATE_RFC2822));
1712 }
1713 }
1714 munmap(log_mapped, mapsz);
1715 return 0;
1716 }
1717 lastrec = rec;
1718 if (cnt > 0)
1719 cnt--;
1720 }
1721
1722 rec = logdata;
1723 while (rec < logend && *rec != '>' && *rec != '\n')
1724 rec++;
1725 if (rec == logend || *rec == '\n')
1726 die("Log %s is corrupt.", logfile);
1727 date = strtoul(rec + 1, &tz_c, 10);
1728 tz = strtoul(tz_c, NULL, 10);
1729 if (get_sha1_hex(logdata, sha1))
1730 die("Log %s is corrupt.", logfile);
1731 if (is_null_sha1(sha1)) {
1732 if (get_sha1_hex(logdata + 41, sha1))
1733 die("Log %s is corrupt.", logfile);
1734 }
1735 if (msg)
1736 *msg = ref_msg(logdata, logend);
1737 munmap(log_mapped, mapsz);
1738
1739 if (cutoff_time)
1740 *cutoff_time = date;
1741 if (cutoff_tz)
1742 *cutoff_tz = tz;
1743 if (cutoff_cnt)
1744 *cutoff_cnt = reccnt;
1745 return 1;
1746}
1747
1748int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1749{
1750 const char *logfile;
1751 FILE *logfp;
1752 struct strbuf sb = STRBUF_INIT;
1753 int ret = 0;
1754
1755 logfile = git_path("logs/%s", ref);
1756 logfp = fopen(logfile, "r");
1757 if (!logfp)
1758 return -1;
1759
1760 if (ofs) {
1761 struct stat statbuf;
1762 if (fstat(fileno(logfp), &statbuf) ||
1763 statbuf.st_size < ofs ||
1764 fseek(logfp, -ofs, SEEK_END) ||
1765 strbuf_getwholeline(&sb, logfp, '\n')) {
1766 fclose(logfp);
1767 strbuf_release(&sb);
1768 return -1;
1769 }
1770 }
1771
1772 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1773 unsigned char osha1[20], nsha1[20];
1774 char *email_end, *message;
1775 unsigned long timestamp;
1776 int tz;
1777
1778 /* old SP new SP name <email> SP time TAB msg LF */
1779 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1780 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1781 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1782 !(email_end = strchr(sb.buf + 82, '>')) ||
1783 email_end[1] != ' ' ||
1784 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1785 !message || message[0] != ' ' ||
1786 (message[1] != '+' && message[1] != '-') ||
1787 !isdigit(message[2]) || !isdigit(message[3]) ||
1788 !isdigit(message[4]) || !isdigit(message[5]))
1789 continue; /* corrupt? */
1790 email_end[1] = '\0';
1791 tz = strtol(message + 1, NULL, 10);
1792 if (message[6] != '\t')
1793 message += 6;
1794 else
1795 message += 7;
1796 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1797 cb_data);
1798 if (ret)
1799 break;
1800 }
1801 fclose(logfp);
1802 strbuf_release(&sb);
1803 return ret;
1804}
1805
1806int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1807{
1808 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1809}
1810
1811static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1812{
1813 DIR *dir = opendir(git_path("logs/%s", base));
1814 int retval = 0;
1815
1816 if (dir) {
1817 struct dirent *de;
1818 int baselen = strlen(base);
1819 char *log = xmalloc(baselen + 257);
1820
1821 memcpy(log, base, baselen);
1822 if (baselen && base[baselen-1] != '/')
1823 log[baselen++] = '/';
1824
1825 while ((de = readdir(dir)) != NULL) {
1826 struct stat st;
1827 int namelen;
1828
1829 if (de->d_name[0] == '.')
1830 continue;
1831 namelen = strlen(de->d_name);
1832 if (namelen > 255)
1833 continue;
1834 if (has_extension(de->d_name, ".lock"))
1835 continue;
1836 memcpy(log + baselen, de->d_name, namelen+1);
1837 if (stat(git_path("logs/%s", log), &st) < 0)
1838 continue;
1839 if (S_ISDIR(st.st_mode)) {
1840 retval = do_for_each_reflog(log, fn, cb_data);
1841 } else {
1842 unsigned char sha1[20];
1843 if (!resolve_ref(log, sha1, 0, NULL))
1844 retval = error("bad ref for %s", log);
1845 else
1846 retval = fn(log, sha1, 0, cb_data);
1847 }
1848 if (retval)
1849 break;
1850 }
1851 free(log);
1852 closedir(dir);
1853 }
1854 else if (*base)
1855 return errno;
1856 return retval;
1857}
1858
1859int for_each_reflog(each_ref_fn fn, void *cb_data)
1860{
1861 return do_for_each_reflog("", fn, cb_data);
1862}
1863
1864int update_ref(const char *action, const char *refname,
1865 const unsigned char *sha1, const unsigned char *oldval,
1866 int flags, enum action_on_err onerr)
1867{
1868 static struct ref_lock *lock;
1869 lock = lock_any_ref_for_update(refname, oldval, flags);
1870 if (!lock) {
1871 const char *str = "Cannot lock the ref '%s'.";
1872 switch (onerr) {
1873 case MSG_ON_ERR: error(str, refname); break;
1874 case DIE_ON_ERR: die(str, refname); break;
1875 case QUIET_ON_ERR: break;
1876 }
1877 return 1;
1878 }
1879 if (write_ref_sha1(lock, sha1, action) < 0) {
1880 const char *str = "Cannot update the ref '%s'.";
1881 switch (onerr) {
1882 case MSG_ON_ERR: error(str, refname); break;
1883 case DIE_ON_ERR: die(str, refname); break;
1884 case QUIET_ON_ERR: break;
1885 }
1886 return 1;
1887 }
1888 return 0;
1889}
1890
1891int ref_exists(char *refname)
1892{
1893 unsigned char sha1[20];
1894 return !!resolve_ref(refname, sha1, 1, NULL);
1895}
1896
1897struct ref *find_ref_by_name(const struct ref *list, const char *name)
1898{
1899 for ( ; list; list = list->next)
1900 if (!strcmp(list->name, name))
1901 return (struct ref *)list;
1902 return NULL;
1903}
1904
1905/*
1906 * generate a format suitable for scanf from a ref_rev_parse_rules
1907 * rule, that is replace the "%.*s" spec with a "%s" spec
1908 */
1909static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1910{
1911 char *spec;
1912
1913 spec = strstr(rule, "%.*s");
1914 if (!spec || strstr(spec + 4, "%.*s"))
1915 die("invalid rule in ref_rev_parse_rules: %s", rule);
1916
1917 /* copy all until spec */
1918 strncpy(scanf_fmt, rule, spec - rule);
1919 scanf_fmt[spec - rule] = '\0';
1920 /* copy new spec */
1921 strcat(scanf_fmt, "%s");
1922 /* copy remaining rule */
1923 strcat(scanf_fmt, spec + 4);
1924
1925 return;
1926}
1927
1928char *shorten_unambiguous_ref(const char *ref, int strict)
1929{
1930 int i;
1931 static char **scanf_fmts;
1932 static int nr_rules;
1933 char *short_name;
1934
1935 /* pre generate scanf formats from ref_rev_parse_rules[] */
1936 if (!nr_rules) {
1937 size_t total_len = 0;
1938
1939 /* the rule list is NULL terminated, count them first */
1940 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1941 /* no +1 because strlen("%s") < strlen("%.*s") */
1942 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1943
1944 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1945
1946 total_len = 0;
1947 for (i = 0; i < nr_rules; i++) {
1948 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1949 + total_len;
1950 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1951 total_len += strlen(ref_rev_parse_rules[i]);
1952 }
1953 }
1954
1955 /* bail out if there are no rules */
1956 if (!nr_rules)
1957 return xstrdup(ref);
1958
1959 /* buffer for scanf result, at most ref must fit */
1960 short_name = xstrdup(ref);
1961
1962 /* skip first rule, it will always match */
1963 for (i = nr_rules - 1; i > 0 ; --i) {
1964 int j;
1965 int rules_to_fail = i;
1966 int short_name_len;
1967
1968 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1969 continue;
1970
1971 short_name_len = strlen(short_name);
1972
1973 /*
1974 * in strict mode, all (except the matched one) rules
1975 * must fail to resolve to a valid non-ambiguous ref
1976 */
1977 if (strict)
1978 rules_to_fail = nr_rules;
1979
1980 /*
1981 * check if the short name resolves to a valid ref,
1982 * but use only rules prior to the matched one
1983 */
1984 for (j = 0; j < rules_to_fail; j++) {
1985 const char *rule = ref_rev_parse_rules[j];
1986 unsigned char short_objectname[20];
1987 char refname[PATH_MAX];
1988
1989 /* skip matched rule */
1990 if (i == j)
1991 continue;
1992
1993 /*
1994 * the short name is ambiguous, if it resolves
1995 * (with this previous rule) to a valid ref
1996 * read_ref() returns 0 on success
1997 */
1998 mksnpath(refname, sizeof(refname),
1999 rule, short_name_len, short_name);
2000 if (!read_ref(refname, short_objectname))
2001 break;
2002 }
2003
2004 /*
2005 * short name is non-ambiguous if all previous rules
2006 * haven't resolved to a valid ref
2007 */
2008 if (j == rules_to_fail)
2009 return short_name;
2010 }
2011
2012 free(short_name);
2013 return xstrdup(ref);
2014}