Merge branch 'jc/pull-signed-tag'
[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=0x01, ISPACKED=0x02 and ISBROKEN=0x04 are public interfaces */
8 #define REF_KNOWS_PEELED 0x10
9
10 struct ref_entry {
11 unsigned char flag; /* ISSYMREF? ISPACKED? */
12 unsigned char sha1[20];
13 unsigned char peeled[20];
14 char name[FLEX_ARRAY];
15 };
16
17 struct ref_array {
18 int nr, alloc;
19 struct ref_entry **refs;
20 };
21
22 static const char *parse_ref_line(char *line, unsigned char *sha1)
23 {
24 /*
25 * 42: the answer to everything.
26 *
27 * In this case, it happens to be the answer to
28 * 40 (length of sha1 hex representation)
29 * +1 (space in between hex and name)
30 * +1 (newline at the end of the line)
31 */
32 int len = strlen(line) - 42;
33
34 if (len <= 0)
35 return NULL;
36 if (get_sha1_hex(line, sha1) < 0)
37 return NULL;
38 if (!isspace(line[40]))
39 return NULL;
40 line += 41;
41 if (isspace(*line))
42 return NULL;
43 if (line[len] != '\n')
44 return NULL;
45 line[len] = 0;
46
47 return line;
48 }
49
50 static void add_ref(const char *name, const unsigned char *sha1,
51 int flag, int check_name, struct ref_array *refs,
52 struct ref_entry **new_entry)
53 {
54 int len;
55 struct ref_entry *entry;
56
57 /* Allocate it and add it in.. */
58 len = strlen(name) + 1;
59 entry = xmalloc(sizeof(struct ref_entry) + len);
60 hashcpy(entry->sha1, sha1);
61 hashclr(entry->peeled);
62 if (check_name &&
63 check_refname_format(name, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
64 die("Reference has invalid format: '%s'", name);
65 memcpy(entry->name, name, len);
66 entry->flag = flag;
67 if (new_entry)
68 *new_entry = entry;
69 ALLOC_GROW(refs->refs, refs->nr + 1, refs->alloc);
70 refs->refs[refs->nr++] = entry;
71 }
72
73 static int ref_entry_cmp(const void *a, const void *b)
74 {
75 struct ref_entry *one = *(struct ref_entry **)a;
76 struct ref_entry *two = *(struct ref_entry **)b;
77 return strcmp(one->name, two->name);
78 }
79
80 static void sort_ref_array(struct ref_array *array)
81 {
82 int i = 0, j = 1;
83
84 /* Nothing to sort unless there are at least two entries */
85 if (array->nr < 2)
86 return;
87
88 qsort(array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
89
90 /* Remove any duplicates from the ref_array */
91 for (; j < array->nr; j++) {
92 struct ref_entry *a = array->refs[i];
93 struct ref_entry *b = array->refs[j];
94 if (!strcmp(a->name, b->name)) {
95 if (hashcmp(a->sha1, b->sha1))
96 die("Duplicated ref, and SHA1s don't match: %s",
97 a->name);
98 warning("Duplicated ref: %s", a->name);
99 free(b);
100 continue;
101 }
102 i++;
103 array->refs[i] = array->refs[j];
104 }
105 array->nr = i + 1;
106 }
107
108 static struct ref_entry *search_ref_array(struct ref_array *array, const char *name)
109 {
110 struct ref_entry *e, **r;
111 int len;
112
113 if (name == NULL)
114 return NULL;
115
116 if (!array->nr)
117 return NULL;
118
119 len = strlen(name) + 1;
120 e = xmalloc(sizeof(struct ref_entry) + len);
121 memcpy(e->name, name, len);
122
123 r = bsearch(&e, array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
124
125 free(e);
126
127 if (r == NULL)
128 return NULL;
129
130 return *r;
131 }
132
133 /*
134 * Future: need to be in "struct repository"
135 * when doing a full libification.
136 */
137 static struct ref_cache {
138 struct ref_cache *next;
139 char did_loose;
140 char did_packed;
141 struct ref_array loose;
142 struct ref_array packed;
143 /* The submodule name, or "" for the main repo. */
144 char name[FLEX_ARRAY];
145 } *ref_cache;
146
147 static struct ref_entry *current_ref;
148
149 static struct ref_array extra_refs;
150
151 static void free_ref_array(struct ref_array *array)
152 {
153 int i;
154 for (i = 0; i < array->nr; i++)
155 free(array->refs[i]);
156 free(array->refs);
157 array->nr = array->alloc = 0;
158 array->refs = NULL;
159 }
160
161 static void clear_packed_ref_cache(struct ref_cache *refs)
162 {
163 if (refs->did_packed)
164 free_ref_array(&refs->packed);
165 refs->did_packed = 0;
166 }
167
168 static void clear_loose_ref_cache(struct ref_cache *refs)
169 {
170 if (refs->did_loose)
171 free_ref_array(&refs->loose);
172 refs->did_loose = 0;
173 }
174
175 static struct ref_cache *create_ref_cache(const char *submodule)
176 {
177 int len;
178 struct ref_cache *refs;
179 if (!submodule)
180 submodule = "";
181 len = strlen(submodule) + 1;
182 refs = xcalloc(1, sizeof(struct ref_cache) + len);
183 memcpy(refs->name, submodule, len);
184 return refs;
185 }
186
187 /*
188 * Return a pointer to a ref_cache for the specified submodule. For
189 * the main repository, use submodule==NULL. The returned structure
190 * will be allocated and initialized but not necessarily populated; it
191 * should not be freed.
192 */
193 static struct ref_cache *get_ref_cache(const char *submodule)
194 {
195 struct ref_cache *refs = ref_cache;
196 if (!submodule)
197 submodule = "";
198 while (refs) {
199 if (!strcmp(submodule, refs->name))
200 return refs;
201 refs = refs->next;
202 }
203
204 refs = create_ref_cache(submodule);
205 refs->next = ref_cache;
206 ref_cache = refs;
207 return refs;
208 }
209
210 void invalidate_ref_cache(const char *submodule)
211 {
212 struct ref_cache *refs = get_ref_cache(submodule);
213 clear_packed_ref_cache(refs);
214 clear_loose_ref_cache(refs);
215 }
216
217 static void read_packed_refs(FILE *f, struct ref_array *array)
218 {
219 struct ref_entry *last = NULL;
220 char refline[PATH_MAX];
221 int flag = REF_ISPACKED;
222
223 while (fgets(refline, sizeof(refline), f)) {
224 unsigned char sha1[20];
225 const char *name;
226 static const char header[] = "# pack-refs with:";
227
228 if (!strncmp(refline, header, sizeof(header)-1)) {
229 const char *traits = refline + sizeof(header) - 1;
230 if (strstr(traits, " peeled "))
231 flag |= REF_KNOWS_PEELED;
232 /* perhaps other traits later as well */
233 continue;
234 }
235
236 name = parse_ref_line(refline, sha1);
237 if (name) {
238 add_ref(name, sha1, flag, 1, array, &last);
239 continue;
240 }
241 if (last &&
242 refline[0] == '^' &&
243 strlen(refline) == 42 &&
244 refline[41] == '\n' &&
245 !get_sha1_hex(refline + 1, sha1))
246 hashcpy(last->peeled, sha1);
247 }
248 sort_ref_array(array);
249 }
250
251 void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
252 {
253 add_ref(name, sha1, flag, 0, &extra_refs, NULL);
254 }
255
256 void clear_extra_refs(void)
257 {
258 free_ref_array(&extra_refs);
259 }
260
261 static struct ref_array *get_packed_refs(const char *submodule)
262 {
263 struct ref_cache *refs = get_ref_cache(submodule);
264
265 if (!refs->did_packed) {
266 const char *packed_refs_file;
267 FILE *f;
268
269 if (submodule)
270 packed_refs_file = git_path_submodule(submodule, "packed-refs");
271 else
272 packed_refs_file = git_path("packed-refs");
273 f = fopen(packed_refs_file, "r");
274 if (f) {
275 read_packed_refs(f, &refs->packed);
276 fclose(f);
277 }
278 refs->did_packed = 1;
279 }
280 return &refs->packed;
281 }
282
283 static void get_ref_dir(const char *submodule, const char *base,
284 struct ref_array *array)
285 {
286 DIR *dir;
287 const char *path;
288
289 if (submodule)
290 path = git_path_submodule(submodule, "%s", base);
291 else
292 path = git_path("%s", base);
293
294
295 dir = opendir(path);
296
297 if (dir) {
298 struct dirent *de;
299 int baselen = strlen(base);
300 char *ref = xmalloc(baselen + 257);
301
302 memcpy(ref, base, baselen);
303 if (baselen && base[baselen-1] != '/')
304 ref[baselen++] = '/';
305
306 while ((de = readdir(dir)) != NULL) {
307 unsigned char sha1[20];
308 struct stat st;
309 int flag;
310 int namelen;
311 const char *refdir;
312
313 if (de->d_name[0] == '.')
314 continue;
315 namelen = strlen(de->d_name);
316 if (namelen > 255)
317 continue;
318 if (has_extension(de->d_name, ".lock"))
319 continue;
320 memcpy(ref + baselen, de->d_name, namelen+1);
321 refdir = submodule
322 ? git_path_submodule(submodule, "%s", ref)
323 : git_path("%s", ref);
324 if (stat(refdir, &st) < 0)
325 continue;
326 if (S_ISDIR(st.st_mode)) {
327 get_ref_dir(submodule, ref, array);
328 continue;
329 }
330 if (submodule) {
331 hashclr(sha1);
332 flag = 0;
333 if (resolve_gitlink_ref(submodule, ref, sha1) < 0) {
334 hashclr(sha1);
335 flag |= REF_ISBROKEN;
336 }
337 } else if (!resolve_ref(ref, sha1, 1, &flag)) {
338 hashclr(sha1);
339 flag |= REF_ISBROKEN;
340 }
341 add_ref(ref, sha1, flag, 1, array, NULL);
342 }
343 free(ref);
344 closedir(dir);
345 }
346 }
347
348 struct warn_if_dangling_data {
349 FILE *fp;
350 const char *refname;
351 const char *msg_fmt;
352 };
353
354 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
355 int flags, void *cb_data)
356 {
357 struct warn_if_dangling_data *d = cb_data;
358 const char *resolves_to;
359 unsigned char junk[20];
360
361 if (!(flags & REF_ISSYMREF))
362 return 0;
363
364 resolves_to = resolve_ref(refname, junk, 0, NULL);
365 if (!resolves_to || strcmp(resolves_to, d->refname))
366 return 0;
367
368 fprintf(d->fp, d->msg_fmt, refname);
369 return 0;
370 }
371
372 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
373 {
374 struct warn_if_dangling_data data;
375
376 data.fp = fp;
377 data.refname = refname;
378 data.msg_fmt = msg_fmt;
379 for_each_rawref(warn_if_dangling_symref, &data);
380 }
381
382 static struct ref_array *get_loose_refs(const char *submodule)
383 {
384 struct ref_cache *refs = get_ref_cache(submodule);
385
386 if (!refs->did_loose) {
387 get_ref_dir(submodule, "refs", &refs->loose);
388 sort_ref_array(&refs->loose);
389 refs->did_loose = 1;
390 }
391 return &refs->loose;
392 }
393
394 /* We allow "recursive" symbolic refs. Only within reason, though */
395 #define MAXDEPTH 5
396 #define MAXREFLEN (1024)
397
398 /*
399 * Called by resolve_gitlink_ref_recursive() after it failed to read
400 * from "name", which is "module/.git/<refname>". Find <refname> in
401 * the packed-refs file for the submodule.
402 */
403 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
404 {
405 int retval = -1;
406 struct ref_entry *ref;
407 struct ref_array *array;
408
409 /* being defensive: resolve_gitlink_ref() did this for us */
410 if (pathlen < 6 || memcmp(name + pathlen - 6, "/.git/", 6))
411 die("Oops");
412 name[pathlen - 6] = '\0'; /* make it path to the submodule */
413 array = get_packed_refs(name);
414 ref = search_ref_array(array, refname);
415 if (ref != NULL) {
416 memcpy(result, ref->sha1, 20);
417 retval = 0;
418 }
419 return retval;
420 }
421
422 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
423 {
424 int fd, len = strlen(refname);
425 char buffer[128], *p;
426
427 if (recursion > MAXDEPTH || len > MAXREFLEN)
428 return -1;
429 memcpy(name + pathlen, refname, len+1);
430 fd = open(name, O_RDONLY);
431 if (fd < 0)
432 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
433
434 len = read(fd, buffer, sizeof(buffer)-1);
435 close(fd);
436 if (len < 0)
437 return -1;
438 while (len && isspace(buffer[len-1]))
439 len--;
440 buffer[len] = 0;
441
442 /* Was it a detached head or an old-fashioned symlink? */
443 if (!get_sha1_hex(buffer, result))
444 return 0;
445
446 /* Symref? */
447 if (strncmp(buffer, "ref:", 4))
448 return -1;
449 p = buffer + 4;
450 while (isspace(*p))
451 p++;
452
453 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
454 }
455
456 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
457 {
458 int len = strlen(path), retval;
459 char *gitdir;
460 const char *tmp;
461
462 while (len && path[len-1] == '/')
463 len--;
464 if (!len)
465 return -1;
466 gitdir = xmalloc(len + MAXREFLEN + 8);
467 memcpy(gitdir, path, len);
468 memcpy(gitdir + len, "/.git", 6);
469 len += 5;
470
471 tmp = read_gitfile(gitdir);
472 if (tmp) {
473 free(gitdir);
474 len = strlen(tmp);
475 gitdir = xmalloc(len + MAXREFLEN + 3);
476 memcpy(gitdir, tmp, len);
477 }
478 gitdir[len] = '/';
479 gitdir[++len] = '\0';
480 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
481 free(gitdir);
482 return retval;
483 }
484
485 /*
486 * Try to read ref from the packed references. On success, set sha1
487 * and return 0; otherwise, return -1.
488 */
489 static int get_packed_ref(const char *ref, unsigned char *sha1)
490 {
491 struct ref_array *packed = get_packed_refs(NULL);
492 struct ref_entry *entry = search_ref_array(packed, ref);
493 if (entry) {
494 hashcpy(sha1, entry->sha1);
495 return 0;
496 }
497 return -1;
498 }
499
500 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
501 {
502 int depth = MAXDEPTH;
503 ssize_t len;
504 char buffer[256];
505 static char ref_buffer[256];
506
507 if (flag)
508 *flag = 0;
509
510 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
511 return NULL;
512
513 for (;;) {
514 char path[PATH_MAX];
515 struct stat st;
516 char *buf;
517 int fd;
518
519 if (--depth < 0)
520 return NULL;
521
522 git_snpath(path, sizeof(path), "%s", ref);
523
524 if (lstat(path, &st) < 0) {
525 if (errno != ENOENT)
526 return NULL;
527 /*
528 * The loose reference file does not exist;
529 * check for a packed reference.
530 */
531 if (!get_packed_ref(ref, sha1)) {
532 if (flag)
533 *flag |= REF_ISPACKED;
534 return ref;
535 }
536 /* The reference is not a packed reference, either. */
537 if (reading) {
538 return NULL;
539 } else {
540 hashclr(sha1);
541 return ref;
542 }
543 }
544
545 /* Follow "normalized" - ie "refs/.." symlinks by hand */
546 if (S_ISLNK(st.st_mode)) {
547 len = readlink(path, buffer, sizeof(buffer)-1);
548 if (len < 0)
549 return NULL;
550 buffer[len] = 0;
551 if (!prefixcmp(buffer, "refs/") &&
552 !check_refname_format(buffer, 0)) {
553 strcpy(ref_buffer, buffer);
554 ref = ref_buffer;
555 if (flag)
556 *flag |= REF_ISSYMREF;
557 continue;
558 }
559 }
560
561 /* Is it a directory? */
562 if (S_ISDIR(st.st_mode)) {
563 errno = EISDIR;
564 return NULL;
565 }
566
567 /*
568 * Anything else, just open it and try to use it as
569 * a ref
570 */
571 fd = open(path, O_RDONLY);
572 if (fd < 0)
573 return NULL;
574 len = read_in_full(fd, buffer, sizeof(buffer)-1);
575 close(fd);
576 if (len < 0)
577 return NULL;
578 while (len && isspace(buffer[len-1]))
579 len--;
580 buffer[len] = '\0';
581
582 /*
583 * Is it a symbolic ref?
584 */
585 if (prefixcmp(buffer, "ref:"))
586 break;
587 if (flag)
588 *flag |= REF_ISSYMREF;
589 buf = buffer + 4;
590 while (isspace(*buf))
591 buf++;
592 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
593 if (flag)
594 *flag |= REF_ISBROKEN;
595 return NULL;
596 }
597 ref = strcpy(ref_buffer, buf);
598 }
599 /* Please note that FETCH_HEAD has a second line containing other data. */
600 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
601 if (flag)
602 *flag |= REF_ISBROKEN;
603 return NULL;
604 }
605 return ref;
606 }
607
608 /* The argument to filter_refs */
609 struct ref_filter {
610 const char *pattern;
611 each_ref_fn *fn;
612 void *cb_data;
613 };
614
615 int read_ref(const char *ref, unsigned char *sha1)
616 {
617 if (resolve_ref(ref, sha1, 1, NULL))
618 return 0;
619 return -1;
620 }
621
622 #define DO_FOR_EACH_INCLUDE_BROKEN 01
623 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
624 int flags, void *cb_data, struct ref_entry *entry)
625 {
626 if (prefixcmp(entry->name, base))
627 return 0;
628
629 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
630 if (entry->flag & REF_ISBROKEN)
631 return 0; /* ignore broken refs e.g. dangling symref */
632 if (!has_sha1_file(entry->sha1)) {
633 error("%s does not point to a valid object!", entry->name);
634 return 0;
635 }
636 }
637 current_ref = entry;
638 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
639 }
640
641 static int filter_refs(const char *ref, const unsigned char *sha, int flags,
642 void *data)
643 {
644 struct ref_filter *filter = (struct ref_filter *)data;
645 if (fnmatch(filter->pattern, ref, 0))
646 return 0;
647 return filter->fn(ref, sha, flags, filter->cb_data);
648 }
649
650 int peel_ref(const char *ref, unsigned char *sha1)
651 {
652 int flag;
653 unsigned char base[20];
654 struct object *o;
655
656 if (current_ref && (current_ref->name == ref
657 || !strcmp(current_ref->name, ref))) {
658 if (current_ref->flag & REF_KNOWS_PEELED) {
659 hashcpy(sha1, current_ref->peeled);
660 return 0;
661 }
662 hashcpy(base, current_ref->sha1);
663 goto fallback;
664 }
665
666 if (!resolve_ref(ref, base, 1, &flag))
667 return -1;
668
669 if ((flag & REF_ISPACKED)) {
670 struct ref_array *array = get_packed_refs(NULL);
671 struct ref_entry *r = search_ref_array(array, ref);
672
673 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
674 hashcpy(sha1, r->peeled);
675 return 0;
676 }
677 }
678
679 fallback:
680 o = parse_object(base);
681 if (o && o->type == OBJ_TAG) {
682 o = deref_tag(o, ref, 0);
683 if (o) {
684 hashcpy(sha1, o->sha1);
685 return 0;
686 }
687 }
688 return -1;
689 }
690
691 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
692 int trim, int flags, void *cb_data)
693 {
694 int retval = 0, i, p = 0, l = 0;
695 struct ref_array *packed = get_packed_refs(submodule);
696 struct ref_array *loose = get_loose_refs(submodule);
697
698 struct ref_array *extra = &extra_refs;
699
700 for (i = 0; i < extra->nr; i++)
701 retval = do_one_ref(base, fn, trim, flags, cb_data, extra->refs[i]);
702
703 while (p < packed->nr && l < loose->nr) {
704 struct ref_entry *entry;
705 int cmp = strcmp(packed->refs[p]->name, loose->refs[l]->name);
706 if (!cmp) {
707 p++;
708 continue;
709 }
710 if (cmp > 0) {
711 entry = loose->refs[l++];
712 } else {
713 entry = packed->refs[p++];
714 }
715 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
716 if (retval)
717 goto end_each;
718 }
719
720 if (l < loose->nr) {
721 p = l;
722 packed = loose;
723 }
724
725 for (; p < packed->nr; p++) {
726 retval = do_one_ref(base, fn, trim, flags, cb_data, packed->refs[p]);
727 if (retval)
728 goto end_each;
729 }
730
731 end_each:
732 current_ref = NULL;
733 return retval;
734 }
735
736
737 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
738 {
739 unsigned char sha1[20];
740 int flag;
741
742 if (submodule) {
743 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
744 return fn("HEAD", sha1, 0, cb_data);
745
746 return 0;
747 }
748
749 if (resolve_ref("HEAD", sha1, 1, &flag))
750 return fn("HEAD", sha1, flag, cb_data);
751
752 return 0;
753 }
754
755 int head_ref(each_ref_fn fn, void *cb_data)
756 {
757 return do_head_ref(NULL, fn, cb_data);
758 }
759
760 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
761 {
762 return do_head_ref(submodule, fn, cb_data);
763 }
764
765 int for_each_ref(each_ref_fn fn, void *cb_data)
766 {
767 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
768 }
769
770 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
771 {
772 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
773 }
774
775 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
776 {
777 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
778 }
779
780 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
781 each_ref_fn fn, void *cb_data)
782 {
783 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
784 }
785
786 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
787 {
788 return for_each_ref_in("refs/tags/", fn, cb_data);
789 }
790
791 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
792 {
793 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
794 }
795
796 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
797 {
798 return for_each_ref_in("refs/heads/", fn, cb_data);
799 }
800
801 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
802 {
803 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
804 }
805
806 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
807 {
808 return for_each_ref_in("refs/remotes/", fn, cb_data);
809 }
810
811 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
812 {
813 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
814 }
815
816 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
817 {
818 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
819 }
820
821 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
822 {
823 struct strbuf buf = STRBUF_INIT;
824 int ret = 0;
825 unsigned char sha1[20];
826 int flag;
827
828 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
829 if (resolve_ref(buf.buf, sha1, 1, &flag))
830 ret = fn(buf.buf, sha1, flag, cb_data);
831 strbuf_release(&buf);
832
833 return ret;
834 }
835
836 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
837 {
838 struct strbuf buf = STRBUF_INIT;
839 int ret;
840 strbuf_addf(&buf, "%srefs/", get_git_namespace());
841 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
842 strbuf_release(&buf);
843 return ret;
844 }
845
846 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
847 const char *prefix, void *cb_data)
848 {
849 struct strbuf real_pattern = STRBUF_INIT;
850 struct ref_filter filter;
851 int ret;
852
853 if (!prefix && prefixcmp(pattern, "refs/"))
854 strbuf_addstr(&real_pattern, "refs/");
855 else if (prefix)
856 strbuf_addstr(&real_pattern, prefix);
857 strbuf_addstr(&real_pattern, pattern);
858
859 if (!has_glob_specials(pattern)) {
860 /* Append implied '/' '*' if not present. */
861 if (real_pattern.buf[real_pattern.len - 1] != '/')
862 strbuf_addch(&real_pattern, '/');
863 /* No need to check for '*', there is none. */
864 strbuf_addch(&real_pattern, '*');
865 }
866
867 filter.pattern = real_pattern.buf;
868 filter.fn = fn;
869 filter.cb_data = cb_data;
870 ret = for_each_ref(filter_refs, &filter);
871
872 strbuf_release(&real_pattern);
873 return ret;
874 }
875
876 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
877 {
878 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
879 }
880
881 int for_each_rawref(each_ref_fn fn, void *cb_data)
882 {
883 return do_for_each_ref(NULL, "", fn, 0,
884 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
885 }
886
887 /*
888 * Make sure "ref" is something reasonable to have under ".git/refs/";
889 * We do not like it if:
890 *
891 * - any path component of it begins with ".", or
892 * - it has double dots "..", or
893 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
894 * - it ends with a "/".
895 * - it ends with ".lock"
896 * - it contains a "\" (backslash)
897 */
898
899 /* Return true iff ch is not allowed in reference names. */
900 static inline int bad_ref_char(int ch)
901 {
902 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
903 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
904 return 1;
905 /* 2.13 Pattern Matching Notation */
906 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
907 return 1;
908 return 0;
909 }
910
911 /*
912 * Try to read one refname component from the front of ref. Return
913 * the length of the component found, or -1 if the component is not
914 * legal.
915 */
916 static int check_refname_component(const char *ref, int flags)
917 {
918 const char *cp;
919 char last = '\0';
920
921 for (cp = ref; ; cp++) {
922 char ch = *cp;
923 if (ch == '\0' || ch == '/')
924 break;
925 if (bad_ref_char(ch))
926 return -1; /* Illegal character in refname. */
927 if (last == '.' && ch == '.')
928 return -1; /* Refname contains "..". */
929 if (last == '@' && ch == '{')
930 return -1; /* Refname contains "@{". */
931 last = ch;
932 }
933 if (cp == ref)
934 return -1; /* Component has zero length. */
935 if (ref[0] == '.') {
936 if (!(flags & REFNAME_DOT_COMPONENT))
937 return -1; /* Component starts with '.'. */
938 /*
939 * Even if leading dots are allowed, don't allow "."
940 * as a component (".." is prevented by a rule above).
941 */
942 if (ref[1] == '\0')
943 return -1; /* Component equals ".". */
944 }
945 if (cp - ref >= 5 && !memcmp(cp - 5, ".lock", 5))
946 return -1; /* Refname ends with ".lock". */
947 return cp - ref;
948 }
949
950 int check_refname_format(const char *ref, int flags)
951 {
952 int component_len, component_count = 0;
953
954 while (1) {
955 /* We are at the start of a path component. */
956 component_len = check_refname_component(ref, flags);
957 if (component_len < 0) {
958 if ((flags & REFNAME_REFSPEC_PATTERN) &&
959 ref[0] == '*' &&
960 (ref[1] == '\0' || ref[1] == '/')) {
961 /* Accept one wildcard as a full refname component. */
962 flags &= ~REFNAME_REFSPEC_PATTERN;
963 component_len = 1;
964 } else {
965 return -1;
966 }
967 }
968 component_count++;
969 if (ref[component_len] == '\0')
970 break;
971 /* Skip to next component. */
972 ref += component_len + 1;
973 }
974
975 if (ref[component_len - 1] == '.')
976 return -1; /* Refname ends with '.'. */
977 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
978 return -1; /* Refname has only one component. */
979 return 0;
980 }
981
982 const char *prettify_refname(const char *name)
983 {
984 return name + (
985 !prefixcmp(name, "refs/heads/") ? 11 :
986 !prefixcmp(name, "refs/tags/") ? 10 :
987 !prefixcmp(name, "refs/remotes/") ? 13 :
988 0);
989 }
990
991 const char *ref_rev_parse_rules[] = {
992 "%.*s",
993 "refs/%.*s",
994 "refs/tags/%.*s",
995 "refs/heads/%.*s",
996 "refs/remotes/%.*s",
997 "refs/remotes/%.*s/HEAD",
998 NULL
999 };
1000
1001 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1002 {
1003 const char **p;
1004 const int abbrev_name_len = strlen(abbrev_name);
1005
1006 for (p = rules; *p; p++) {
1007 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1008 return 1;
1009 }
1010 }
1011
1012 return 0;
1013 }
1014
1015 static struct ref_lock *verify_lock(struct ref_lock *lock,
1016 const unsigned char *old_sha1, int mustexist)
1017 {
1018 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
1019 error("Can't verify ref %s", lock->ref_name);
1020 unlock_ref(lock);
1021 return NULL;
1022 }
1023 if (hashcmp(lock->old_sha1, old_sha1)) {
1024 error("Ref %s is at %s but expected %s", lock->ref_name,
1025 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1026 unlock_ref(lock);
1027 return NULL;
1028 }
1029 return lock;
1030 }
1031
1032 static int remove_empty_directories(const char *file)
1033 {
1034 /* we want to create a file but there is a directory there;
1035 * if that is an empty directory (or a directory that contains
1036 * only empty directories), remove them.
1037 */
1038 struct strbuf path;
1039 int result;
1040
1041 strbuf_init(&path, 20);
1042 strbuf_addstr(&path, file);
1043
1044 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1045
1046 strbuf_release(&path);
1047
1048 return result;
1049 }
1050
1051 static int is_refname_available(const char *ref, const char *oldref,
1052 struct ref_array *array, int quiet)
1053 {
1054 int i, namlen = strlen(ref); /* e.g. 'foo/bar' */
1055 for (i = 0; i < array->nr; i++ ) {
1056 struct ref_entry *entry = array->refs[i];
1057 /* entry->name could be 'foo' or 'foo/bar/baz' */
1058 if (!oldref || strcmp(oldref, entry->name)) {
1059 int len = strlen(entry->name);
1060 int cmplen = (namlen < len) ? namlen : len;
1061 const char *lead = (namlen < len) ? entry->name : ref;
1062 if (!strncmp(ref, entry->name, cmplen) &&
1063 lead[cmplen] == '/') {
1064 if (!quiet)
1065 error("'%s' exists; cannot create '%s'",
1066 entry->name, ref);
1067 return 0;
1068 }
1069 }
1070 }
1071 return 1;
1072 }
1073
1074 /*
1075 * *string and *len will only be substituted, and *string returned (for
1076 * later free()ing) if the string passed in is a magic short-hand form
1077 * to name a branch.
1078 */
1079 static char *substitute_branch_name(const char **string, int *len)
1080 {
1081 struct strbuf buf = STRBUF_INIT;
1082 int ret = interpret_branch_name(*string, &buf);
1083
1084 if (ret == *len) {
1085 size_t size;
1086 *string = strbuf_detach(&buf, &size);
1087 *len = size;
1088 return (char *)*string;
1089 }
1090
1091 return NULL;
1092 }
1093
1094 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1095 {
1096 char *last_branch = substitute_branch_name(&str, &len);
1097 const char **p, *r;
1098 int refs_found = 0;
1099
1100 *ref = NULL;
1101 for (p = ref_rev_parse_rules; *p; p++) {
1102 char fullref[PATH_MAX];
1103 unsigned char sha1_from_ref[20];
1104 unsigned char *this_result;
1105 int flag;
1106
1107 this_result = refs_found ? sha1_from_ref : sha1;
1108 mksnpath(fullref, sizeof(fullref), *p, len, str);
1109 r = resolve_ref(fullref, this_result, 1, &flag);
1110 if (r) {
1111 if (!refs_found++)
1112 *ref = xstrdup(r);
1113 if (!warn_ambiguous_refs)
1114 break;
1115 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
1116 warning("ignoring dangling symref %s.", fullref);
1117 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1118 warning("ignoring broken ref %s.", fullref);
1119 }
1120 }
1121 free(last_branch);
1122 return refs_found;
1123 }
1124
1125 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1126 {
1127 char *last_branch = substitute_branch_name(&str, &len);
1128 const char **p;
1129 int logs_found = 0;
1130
1131 *log = NULL;
1132 for (p = ref_rev_parse_rules; *p; p++) {
1133 struct stat st;
1134 unsigned char hash[20];
1135 char path[PATH_MAX];
1136 const char *ref, *it;
1137
1138 mksnpath(path, sizeof(path), *p, len, str);
1139 ref = resolve_ref(path, hash, 1, NULL);
1140 if (!ref)
1141 continue;
1142 if (!stat(git_path("logs/%s", path), &st) &&
1143 S_ISREG(st.st_mode))
1144 it = path;
1145 else if (strcmp(ref, path) &&
1146 !stat(git_path("logs/%s", ref), &st) &&
1147 S_ISREG(st.st_mode))
1148 it = ref;
1149 else
1150 continue;
1151 if (!logs_found++) {
1152 *log = xstrdup(it);
1153 hashcpy(sha1, hash);
1154 }
1155 if (!warn_ambiguous_refs)
1156 break;
1157 }
1158 free(last_branch);
1159 return logs_found;
1160 }
1161
1162 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
1163 {
1164 char *ref_file;
1165 const char *orig_ref = ref;
1166 struct ref_lock *lock;
1167 int last_errno = 0;
1168 int type, lflags;
1169 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1170 int missing = 0;
1171
1172 lock = xcalloc(1, sizeof(struct ref_lock));
1173 lock->lock_fd = -1;
1174
1175 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
1176 if (!ref && errno == EISDIR) {
1177 /* we are trying to lock foo but we used to
1178 * have foo/bar which now does not exist;
1179 * it is normal for the empty directory 'foo'
1180 * to remain.
1181 */
1182 ref_file = git_path("%s", orig_ref);
1183 if (remove_empty_directories(ref_file)) {
1184 last_errno = errno;
1185 error("there are still refs under '%s'", orig_ref);
1186 goto error_return;
1187 }
1188 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
1189 }
1190 if (type_p)
1191 *type_p = type;
1192 if (!ref) {
1193 last_errno = errno;
1194 error("unable to resolve reference %s: %s",
1195 orig_ref, strerror(errno));
1196 goto error_return;
1197 }
1198 missing = is_null_sha1(lock->old_sha1);
1199 /* When the ref did not exist and we are creating it,
1200 * make sure there is no existing ref that is packed
1201 * whose name begins with our refname, nor a ref whose
1202 * name is a proper prefix of our refname.
1203 */
1204 if (missing &&
1205 !is_refname_available(ref, NULL, get_packed_refs(NULL), 0)) {
1206 last_errno = ENOTDIR;
1207 goto error_return;
1208 }
1209
1210 lock->lk = xcalloc(1, sizeof(struct lock_file));
1211
1212 lflags = LOCK_DIE_ON_ERROR;
1213 if (flags & REF_NODEREF) {
1214 ref = orig_ref;
1215 lflags |= LOCK_NODEREF;
1216 }
1217 lock->ref_name = xstrdup(ref);
1218 lock->orig_ref_name = xstrdup(orig_ref);
1219 ref_file = git_path("%s", ref);
1220 if (missing)
1221 lock->force_write = 1;
1222 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1223 lock->force_write = 1;
1224
1225 if (safe_create_leading_directories(ref_file)) {
1226 last_errno = errno;
1227 error("unable to create directory for %s", ref_file);
1228 goto error_return;
1229 }
1230
1231 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1232 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1233
1234 error_return:
1235 unlock_ref(lock);
1236 errno = last_errno;
1237 return NULL;
1238 }
1239
1240 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
1241 {
1242 char refpath[PATH_MAX];
1243 if (check_refname_format(ref, 0))
1244 return NULL;
1245 strcpy(refpath, mkpath("refs/%s", ref));
1246 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1247 }
1248
1249 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
1250 {
1251 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
1252 return NULL;
1253 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1254 }
1255
1256 static struct lock_file packlock;
1257
1258 static int repack_without_ref(const char *refname)
1259 {
1260 struct ref_array *packed;
1261 struct ref_entry *ref;
1262 int fd, i;
1263
1264 packed = get_packed_refs(NULL);
1265 ref = search_ref_array(packed, refname);
1266 if (ref == NULL)
1267 return 0;
1268 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1269 if (fd < 0) {
1270 unable_to_lock_error(git_path("packed-refs"), errno);
1271 return error("cannot delete '%s' from packed refs", refname);
1272 }
1273
1274 for (i = 0; i < packed->nr; i++) {
1275 char line[PATH_MAX + 100];
1276 int len;
1277
1278 ref = packed->refs[i];
1279
1280 if (!strcmp(refname, ref->name))
1281 continue;
1282 len = snprintf(line, sizeof(line), "%s %s\n",
1283 sha1_to_hex(ref->sha1), ref->name);
1284 /* this should not happen but just being defensive */
1285 if (len > sizeof(line))
1286 die("too long a refname '%s'", ref->name);
1287 write_or_die(fd, line, len);
1288 }
1289 return commit_lock_file(&packlock);
1290 }
1291
1292 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1293 {
1294 struct ref_lock *lock;
1295 int err, i = 0, ret = 0, flag = 0;
1296
1297 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1298 if (!lock)
1299 return 1;
1300 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1301 /* loose */
1302 const char *path;
1303
1304 if (!(delopt & REF_NODEREF)) {
1305 i = strlen(lock->lk->filename) - 5; /* .lock */
1306 lock->lk->filename[i] = 0;
1307 path = lock->lk->filename;
1308 } else {
1309 path = git_path("%s", refname);
1310 }
1311 err = unlink_or_warn(path);
1312 if (err && errno != ENOENT)
1313 ret = 1;
1314
1315 if (!(delopt & REF_NODEREF))
1316 lock->lk->filename[i] = '.';
1317 }
1318 /* removing the loose one could have resurrected an earlier
1319 * packed one. Also, if it was not loose we need to repack
1320 * without it.
1321 */
1322 ret |= repack_without_ref(refname);
1323
1324 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1325 invalidate_ref_cache(NULL);
1326 unlock_ref(lock);
1327 return ret;
1328 }
1329
1330 /*
1331 * People using contrib's git-new-workdir have .git/logs/refs ->
1332 * /some/other/path/.git/logs/refs, and that may live on another device.
1333 *
1334 * IOW, to avoid cross device rename errors, the temporary renamed log must
1335 * live into logs/refs.
1336 */
1337 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1338
1339 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1340 {
1341 unsigned char sha1[20], orig_sha1[20];
1342 int flag = 0, logmoved = 0;
1343 struct ref_lock *lock;
1344 struct stat loginfo;
1345 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1346 const char *symref = NULL;
1347
1348 if (log && S_ISLNK(loginfo.st_mode))
1349 return error("reflog for %s is a symlink", oldref);
1350
1351 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1352 if (flag & REF_ISSYMREF)
1353 return error("refname %s is a symbolic ref, renaming it is not supported",
1354 oldref);
1355 if (!symref)
1356 return error("refname %s not found", oldref);
1357
1358 if (!is_refname_available(newref, oldref, get_packed_refs(NULL), 0))
1359 return 1;
1360
1361 if (!is_refname_available(newref, oldref, get_loose_refs(NULL), 0))
1362 return 1;
1363
1364 if (log && rename(git_path("logs/%s", oldref), git_path(TMP_RENAMED_LOG)))
1365 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1366 oldref, strerror(errno));
1367
1368 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1369 error("unable to delete old %s", oldref);
1370 goto rollback;
1371 }
1372
1373 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1374 if (errno==EISDIR) {
1375 if (remove_empty_directories(git_path("%s", newref))) {
1376 error("Directory not empty: %s", newref);
1377 goto rollback;
1378 }
1379 } else {
1380 error("unable to delete existing %s", newref);
1381 goto rollback;
1382 }
1383 }
1384
1385 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1386 error("unable to create directory for %s", newref);
1387 goto rollback;
1388 }
1389
1390 retry:
1391 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newref))) {
1392 if (errno==EISDIR || errno==ENOTDIR) {
1393 /*
1394 * rename(a, b) when b is an existing
1395 * directory ought to result in ISDIR, but
1396 * Solaris 5.8 gives ENOTDIR. Sheesh.
1397 */
1398 if (remove_empty_directories(git_path("logs/%s", newref))) {
1399 error("Directory not empty: logs/%s", newref);
1400 goto rollback;
1401 }
1402 goto retry;
1403 } else {
1404 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1405 newref, strerror(errno));
1406 goto rollback;
1407 }
1408 }
1409 logmoved = log;
1410
1411 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1412 if (!lock) {
1413 error("unable to lock %s for update", newref);
1414 goto rollback;
1415 }
1416 lock->force_write = 1;
1417 hashcpy(lock->old_sha1, orig_sha1);
1418 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1419 error("unable to write current sha1 into %s", newref);
1420 goto rollback;
1421 }
1422
1423 return 0;
1424
1425 rollback:
1426 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1427 if (!lock) {
1428 error("unable to lock %s for rollback", oldref);
1429 goto rollbacklog;
1430 }
1431
1432 lock->force_write = 1;
1433 flag = log_all_ref_updates;
1434 log_all_ref_updates = 0;
1435 if (write_ref_sha1(lock, orig_sha1, NULL))
1436 error("unable to write current sha1 into %s", oldref);
1437 log_all_ref_updates = flag;
1438
1439 rollbacklog:
1440 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1441 error("unable to restore logfile %s from %s: %s",
1442 oldref, newref, strerror(errno));
1443 if (!logmoved && log &&
1444 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldref)))
1445 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1446 oldref, strerror(errno));
1447
1448 return 1;
1449 }
1450
1451 int close_ref(struct ref_lock *lock)
1452 {
1453 if (close_lock_file(lock->lk))
1454 return -1;
1455 lock->lock_fd = -1;
1456 return 0;
1457 }
1458
1459 int commit_ref(struct ref_lock *lock)
1460 {
1461 if (commit_lock_file(lock->lk))
1462 return -1;
1463 lock->lock_fd = -1;
1464 return 0;
1465 }
1466
1467 void unlock_ref(struct ref_lock *lock)
1468 {
1469 /* Do not free lock->lk -- atexit() still looks at them */
1470 if (lock->lk)
1471 rollback_lock_file(lock->lk);
1472 free(lock->ref_name);
1473 free(lock->orig_ref_name);
1474 free(lock);
1475 }
1476
1477 /*
1478 * copy the reflog message msg to buf, which has been allocated sufficiently
1479 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1480 * because reflog file is one line per entry.
1481 */
1482 static int copy_msg(char *buf, const char *msg)
1483 {
1484 char *cp = buf;
1485 char c;
1486 int wasspace = 1;
1487
1488 *cp++ = '\t';
1489 while ((c = *msg++)) {
1490 if (wasspace && isspace(c))
1491 continue;
1492 wasspace = isspace(c);
1493 if (wasspace)
1494 c = ' ';
1495 *cp++ = c;
1496 }
1497 while (buf < cp && isspace(cp[-1]))
1498 cp--;
1499 *cp++ = '\n';
1500 return cp - buf;
1501 }
1502
1503 int log_ref_setup(const char *ref_name, char *logfile, int bufsize)
1504 {
1505 int logfd, oflags = O_APPEND | O_WRONLY;
1506
1507 git_snpath(logfile, bufsize, "logs/%s", ref_name);
1508 if (log_all_ref_updates &&
1509 (!prefixcmp(ref_name, "refs/heads/") ||
1510 !prefixcmp(ref_name, "refs/remotes/") ||
1511 !prefixcmp(ref_name, "refs/notes/") ||
1512 !strcmp(ref_name, "HEAD"))) {
1513 if (safe_create_leading_directories(logfile) < 0)
1514 return error("unable to create directory for %s",
1515 logfile);
1516 oflags |= O_CREAT;
1517 }
1518
1519 logfd = open(logfile, oflags, 0666);
1520 if (logfd < 0) {
1521 if (!(oflags & O_CREAT) && errno == ENOENT)
1522 return 0;
1523
1524 if ((oflags & O_CREAT) && errno == EISDIR) {
1525 if (remove_empty_directories(logfile)) {
1526 return error("There are still logs under '%s'",
1527 logfile);
1528 }
1529 logfd = open(logfile, oflags, 0666);
1530 }
1531
1532 if (logfd < 0)
1533 return error("Unable to append to %s: %s",
1534 logfile, strerror(errno));
1535 }
1536
1537 adjust_shared_perm(logfile);
1538 close(logfd);
1539 return 0;
1540 }
1541
1542 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1543 const unsigned char *new_sha1, const char *msg)
1544 {
1545 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1546 unsigned maxlen, len;
1547 int msglen;
1548 char log_file[PATH_MAX];
1549 char *logrec;
1550 const char *committer;
1551
1552 if (log_all_ref_updates < 0)
1553 log_all_ref_updates = !is_bare_repository();
1554
1555 result = log_ref_setup(ref_name, log_file, sizeof(log_file));
1556 if (result)
1557 return result;
1558
1559 logfd = open(log_file, oflags);
1560 if (logfd < 0)
1561 return 0;
1562 msglen = msg ? strlen(msg) : 0;
1563 committer = git_committer_info(0);
1564 maxlen = strlen(committer) + msglen + 100;
1565 logrec = xmalloc(maxlen);
1566 len = sprintf(logrec, "%s %s %s\n",
1567 sha1_to_hex(old_sha1),
1568 sha1_to_hex(new_sha1),
1569 committer);
1570 if (msglen)
1571 len += copy_msg(logrec + len - 1, msg) - 1;
1572 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1573 free(logrec);
1574 if (close(logfd) != 0 || written != len)
1575 return error("Unable to append to %s", log_file);
1576 return 0;
1577 }
1578
1579 static int is_branch(const char *refname)
1580 {
1581 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1582 }
1583
1584 int write_ref_sha1(struct ref_lock *lock,
1585 const unsigned char *sha1, const char *logmsg)
1586 {
1587 static char term = '\n';
1588 struct object *o;
1589
1590 if (!lock)
1591 return -1;
1592 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1593 unlock_ref(lock);
1594 return 0;
1595 }
1596 o = parse_object(sha1);
1597 if (!o) {
1598 error("Trying to write ref %s with nonexistent object %s",
1599 lock->ref_name, sha1_to_hex(sha1));
1600 unlock_ref(lock);
1601 return -1;
1602 }
1603 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1604 error("Trying to write non-commit object %s to branch %s",
1605 sha1_to_hex(sha1), lock->ref_name);
1606 unlock_ref(lock);
1607 return -1;
1608 }
1609 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1610 write_in_full(lock->lock_fd, &term, 1) != 1
1611 || close_ref(lock) < 0) {
1612 error("Couldn't write %s", lock->lk->filename);
1613 unlock_ref(lock);
1614 return -1;
1615 }
1616 clear_loose_ref_cache(get_ref_cache(NULL));
1617 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1618 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1619 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1620 unlock_ref(lock);
1621 return -1;
1622 }
1623 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1624 /*
1625 * Special hack: If a branch is updated directly and HEAD
1626 * points to it (may happen on the remote side of a push
1627 * for example) then logically the HEAD reflog should be
1628 * updated too.
1629 * A generic solution implies reverse symref information,
1630 * but finding all symrefs pointing to the given branch
1631 * would be rather costly for this rare event (the direct
1632 * update of a branch) to be worth it. So let's cheat and
1633 * check with HEAD only which should cover 99% of all usage
1634 * scenarios (even 100% of the default ones).
1635 */
1636 unsigned char head_sha1[20];
1637 int head_flag;
1638 const char *head_ref;
1639 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1640 if (head_ref && (head_flag & REF_ISSYMREF) &&
1641 !strcmp(head_ref, lock->ref_name))
1642 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1643 }
1644 if (commit_ref(lock)) {
1645 error("Couldn't set %s", lock->ref_name);
1646 unlock_ref(lock);
1647 return -1;
1648 }
1649 unlock_ref(lock);
1650 return 0;
1651 }
1652
1653 int create_symref(const char *ref_target, const char *refs_heads_master,
1654 const char *logmsg)
1655 {
1656 const char *lockpath;
1657 char ref[1000];
1658 int fd, len, written;
1659 char *git_HEAD = git_pathdup("%s", ref_target);
1660 unsigned char old_sha1[20], new_sha1[20];
1661
1662 if (logmsg && read_ref(ref_target, old_sha1))
1663 hashclr(old_sha1);
1664
1665 if (safe_create_leading_directories(git_HEAD) < 0)
1666 return error("unable to create directory for %s", git_HEAD);
1667
1668 #ifndef NO_SYMLINK_HEAD
1669 if (prefer_symlink_refs) {
1670 unlink(git_HEAD);
1671 if (!symlink(refs_heads_master, git_HEAD))
1672 goto done;
1673 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1674 }
1675 #endif
1676
1677 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1678 if (sizeof(ref) <= len) {
1679 error("refname too long: %s", refs_heads_master);
1680 goto error_free_return;
1681 }
1682 lockpath = mkpath("%s.lock", git_HEAD);
1683 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1684 if (fd < 0) {
1685 error("Unable to open %s for writing", lockpath);
1686 goto error_free_return;
1687 }
1688 written = write_in_full(fd, ref, len);
1689 if (close(fd) != 0 || written != len) {
1690 error("Unable to write to %s", lockpath);
1691 goto error_unlink_return;
1692 }
1693 if (rename(lockpath, git_HEAD) < 0) {
1694 error("Unable to create %s", git_HEAD);
1695 goto error_unlink_return;
1696 }
1697 if (adjust_shared_perm(git_HEAD)) {
1698 error("Unable to fix permissions on %s", lockpath);
1699 error_unlink_return:
1700 unlink_or_warn(lockpath);
1701 error_free_return:
1702 free(git_HEAD);
1703 return -1;
1704 }
1705
1706 #ifndef NO_SYMLINK_HEAD
1707 done:
1708 #endif
1709 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1710 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1711
1712 free(git_HEAD);
1713 return 0;
1714 }
1715
1716 static char *ref_msg(const char *line, const char *endp)
1717 {
1718 const char *ep;
1719 line += 82;
1720 ep = memchr(line, '\n', endp - line);
1721 if (!ep)
1722 ep = endp;
1723 return xmemdupz(line, ep - line);
1724 }
1725
1726 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)
1727 {
1728 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1729 char *tz_c;
1730 int logfd, tz, reccnt = 0;
1731 struct stat st;
1732 unsigned long date;
1733 unsigned char logged_sha1[20];
1734 void *log_mapped;
1735 size_t mapsz;
1736
1737 logfile = git_path("logs/%s", ref);
1738 logfd = open(logfile, O_RDONLY, 0);
1739 if (logfd < 0)
1740 die_errno("Unable to read log '%s'", logfile);
1741 fstat(logfd, &st);
1742 if (!st.st_size)
1743 die("Log %s is empty.", logfile);
1744 mapsz = xsize_t(st.st_size);
1745 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1746 logdata = log_mapped;
1747 close(logfd);
1748
1749 lastrec = NULL;
1750 rec = logend = logdata + st.st_size;
1751 while (logdata < rec) {
1752 reccnt++;
1753 if (logdata < rec && *(rec-1) == '\n')
1754 rec--;
1755 lastgt = NULL;
1756 while (logdata < rec && *(rec-1) != '\n') {
1757 rec--;
1758 if (*rec == '>')
1759 lastgt = rec;
1760 }
1761 if (!lastgt)
1762 die("Log %s is corrupt.", logfile);
1763 date = strtoul(lastgt + 1, &tz_c, 10);
1764 if (date <= at_time || cnt == 0) {
1765 tz = strtoul(tz_c, NULL, 10);
1766 if (msg)
1767 *msg = ref_msg(rec, logend);
1768 if (cutoff_time)
1769 *cutoff_time = date;
1770 if (cutoff_tz)
1771 *cutoff_tz = tz;
1772 if (cutoff_cnt)
1773 *cutoff_cnt = reccnt - 1;
1774 if (lastrec) {
1775 if (get_sha1_hex(lastrec, logged_sha1))
1776 die("Log %s is corrupt.", logfile);
1777 if (get_sha1_hex(rec + 41, sha1))
1778 die("Log %s is corrupt.", logfile);
1779 if (hashcmp(logged_sha1, sha1)) {
1780 warning("Log %s has gap after %s.",
1781 logfile, show_date(date, tz, DATE_RFC2822));
1782 }
1783 }
1784 else if (date == at_time) {
1785 if (get_sha1_hex(rec + 41, sha1))
1786 die("Log %s is corrupt.", logfile);
1787 }
1788 else {
1789 if (get_sha1_hex(rec + 41, logged_sha1))
1790 die("Log %s is corrupt.", logfile);
1791 if (hashcmp(logged_sha1, sha1)) {
1792 warning("Log %s unexpectedly ended on %s.",
1793 logfile, show_date(date, tz, DATE_RFC2822));
1794 }
1795 }
1796 munmap(log_mapped, mapsz);
1797 return 0;
1798 }
1799 lastrec = rec;
1800 if (cnt > 0)
1801 cnt--;
1802 }
1803
1804 rec = logdata;
1805 while (rec < logend && *rec != '>' && *rec != '\n')
1806 rec++;
1807 if (rec == logend || *rec == '\n')
1808 die("Log %s is corrupt.", logfile);
1809 date = strtoul(rec + 1, &tz_c, 10);
1810 tz = strtoul(tz_c, NULL, 10);
1811 if (get_sha1_hex(logdata, sha1))
1812 die("Log %s is corrupt.", logfile);
1813 if (is_null_sha1(sha1)) {
1814 if (get_sha1_hex(logdata + 41, sha1))
1815 die("Log %s is corrupt.", logfile);
1816 }
1817 if (msg)
1818 *msg = ref_msg(logdata, logend);
1819 munmap(log_mapped, mapsz);
1820
1821 if (cutoff_time)
1822 *cutoff_time = date;
1823 if (cutoff_tz)
1824 *cutoff_tz = tz;
1825 if (cutoff_cnt)
1826 *cutoff_cnt = reccnt;
1827 return 1;
1828 }
1829
1830 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1831 {
1832 const char *logfile;
1833 FILE *logfp;
1834 struct strbuf sb = STRBUF_INIT;
1835 int ret = 0;
1836
1837 logfile = git_path("logs/%s", ref);
1838 logfp = fopen(logfile, "r");
1839 if (!logfp)
1840 return -1;
1841
1842 if (ofs) {
1843 struct stat statbuf;
1844 if (fstat(fileno(logfp), &statbuf) ||
1845 statbuf.st_size < ofs ||
1846 fseek(logfp, -ofs, SEEK_END) ||
1847 strbuf_getwholeline(&sb, logfp, '\n')) {
1848 fclose(logfp);
1849 strbuf_release(&sb);
1850 return -1;
1851 }
1852 }
1853
1854 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1855 unsigned char osha1[20], nsha1[20];
1856 char *email_end, *message;
1857 unsigned long timestamp;
1858 int tz;
1859
1860 /* old SP new SP name <email> SP time TAB msg LF */
1861 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1862 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1863 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1864 !(email_end = strchr(sb.buf + 82, '>')) ||
1865 email_end[1] != ' ' ||
1866 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1867 !message || message[0] != ' ' ||
1868 (message[1] != '+' && message[1] != '-') ||
1869 !isdigit(message[2]) || !isdigit(message[3]) ||
1870 !isdigit(message[4]) || !isdigit(message[5]))
1871 continue; /* corrupt? */
1872 email_end[1] = '\0';
1873 tz = strtol(message + 1, NULL, 10);
1874 if (message[6] != '\t')
1875 message += 6;
1876 else
1877 message += 7;
1878 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1879 cb_data);
1880 if (ret)
1881 break;
1882 }
1883 fclose(logfp);
1884 strbuf_release(&sb);
1885 return ret;
1886 }
1887
1888 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1889 {
1890 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1891 }
1892
1893 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1894 {
1895 DIR *dir = opendir(git_path("logs/%s", base));
1896 int retval = 0;
1897
1898 if (dir) {
1899 struct dirent *de;
1900 int baselen = strlen(base);
1901 char *log = xmalloc(baselen + 257);
1902
1903 memcpy(log, base, baselen);
1904 if (baselen && base[baselen-1] != '/')
1905 log[baselen++] = '/';
1906
1907 while ((de = readdir(dir)) != NULL) {
1908 struct stat st;
1909 int namelen;
1910
1911 if (de->d_name[0] == '.')
1912 continue;
1913 namelen = strlen(de->d_name);
1914 if (namelen > 255)
1915 continue;
1916 if (has_extension(de->d_name, ".lock"))
1917 continue;
1918 memcpy(log + baselen, de->d_name, namelen+1);
1919 if (stat(git_path("logs/%s", log), &st) < 0)
1920 continue;
1921 if (S_ISDIR(st.st_mode)) {
1922 retval = do_for_each_reflog(log, fn, cb_data);
1923 } else {
1924 unsigned char sha1[20];
1925 if (!resolve_ref(log, sha1, 0, NULL))
1926 retval = error("bad ref for %s", log);
1927 else
1928 retval = fn(log, sha1, 0, cb_data);
1929 }
1930 if (retval)
1931 break;
1932 }
1933 free(log);
1934 closedir(dir);
1935 }
1936 else if (*base)
1937 return errno;
1938 return retval;
1939 }
1940
1941 int for_each_reflog(each_ref_fn fn, void *cb_data)
1942 {
1943 return do_for_each_reflog("", fn, cb_data);
1944 }
1945
1946 int update_ref(const char *action, const char *refname,
1947 const unsigned char *sha1, const unsigned char *oldval,
1948 int flags, enum action_on_err onerr)
1949 {
1950 static struct ref_lock *lock;
1951 lock = lock_any_ref_for_update(refname, oldval, flags);
1952 if (!lock) {
1953 const char *str = "Cannot lock the ref '%s'.";
1954 switch (onerr) {
1955 case MSG_ON_ERR: error(str, refname); break;
1956 case DIE_ON_ERR: die(str, refname); break;
1957 case QUIET_ON_ERR: break;
1958 }
1959 return 1;
1960 }
1961 if (write_ref_sha1(lock, sha1, action) < 0) {
1962 const char *str = "Cannot update the ref '%s'.";
1963 switch (onerr) {
1964 case MSG_ON_ERR: error(str, refname); break;
1965 case DIE_ON_ERR: die(str, refname); break;
1966 case QUIET_ON_ERR: break;
1967 }
1968 return 1;
1969 }
1970 return 0;
1971 }
1972
1973 int ref_exists(const char *refname)
1974 {
1975 unsigned char sha1[20];
1976 return !!resolve_ref(refname, sha1, 1, NULL);
1977 }
1978
1979 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1980 {
1981 for ( ; list; list = list->next)
1982 if (!strcmp(list->name, name))
1983 return (struct ref *)list;
1984 return NULL;
1985 }
1986
1987 /*
1988 * generate a format suitable for scanf from a ref_rev_parse_rules
1989 * rule, that is replace the "%.*s" spec with a "%s" spec
1990 */
1991 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1992 {
1993 char *spec;
1994
1995 spec = strstr(rule, "%.*s");
1996 if (!spec || strstr(spec + 4, "%.*s"))
1997 die("invalid rule in ref_rev_parse_rules: %s", rule);
1998
1999 /* copy all until spec */
2000 strncpy(scanf_fmt, rule, spec - rule);
2001 scanf_fmt[spec - rule] = '\0';
2002 /* copy new spec */
2003 strcat(scanf_fmt, "%s");
2004 /* copy remaining rule */
2005 strcat(scanf_fmt, spec + 4);
2006
2007 return;
2008 }
2009
2010 char *shorten_unambiguous_ref(const char *ref, int strict)
2011 {
2012 int i;
2013 static char **scanf_fmts;
2014 static int nr_rules;
2015 char *short_name;
2016
2017 /* pre generate scanf formats from ref_rev_parse_rules[] */
2018 if (!nr_rules) {
2019 size_t total_len = 0;
2020
2021 /* the rule list is NULL terminated, count them first */
2022 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2023 /* no +1 because strlen("%s") < strlen("%.*s") */
2024 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2025
2026 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2027
2028 total_len = 0;
2029 for (i = 0; i < nr_rules; i++) {
2030 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2031 + total_len;
2032 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2033 total_len += strlen(ref_rev_parse_rules[i]);
2034 }
2035 }
2036
2037 /* bail out if there are no rules */
2038 if (!nr_rules)
2039 return xstrdup(ref);
2040
2041 /* buffer for scanf result, at most ref must fit */
2042 short_name = xstrdup(ref);
2043
2044 /* skip first rule, it will always match */
2045 for (i = nr_rules - 1; i > 0 ; --i) {
2046 int j;
2047 int rules_to_fail = i;
2048 int short_name_len;
2049
2050 if (1 != sscanf(ref, scanf_fmts[i], short_name))
2051 continue;
2052
2053 short_name_len = strlen(short_name);
2054
2055 /*
2056 * in strict mode, all (except the matched one) rules
2057 * must fail to resolve to a valid non-ambiguous ref
2058 */
2059 if (strict)
2060 rules_to_fail = nr_rules;
2061
2062 /*
2063 * check if the short name resolves to a valid ref,
2064 * but use only rules prior to the matched one
2065 */
2066 for (j = 0; j < rules_to_fail; j++) {
2067 const char *rule = ref_rev_parse_rules[j];
2068 unsigned char short_objectname[20];
2069 char refname[PATH_MAX];
2070
2071 /* skip matched rule */
2072 if (i == j)
2073 continue;
2074
2075 /*
2076 * the short name is ambiguous, if it resolves
2077 * (with this previous rule) to a valid ref
2078 * read_ref() returns 0 on success
2079 */
2080 mksnpath(refname, sizeof(refname),
2081 rule, short_name_len, short_name);
2082 if (!read_ref(refname, short_objectname))
2083 break;
2084 }
2085
2086 /*
2087 * short name is non-ambiguous if all previous rules
2088 * haven't resolved to a valid ref
2089 */
2090 if (j == rules_to_fail)
2091 return short_name;
2092 }
2093
2094 free(short_name);
2095 return xstrdup(ref);
2096 }