Merge branch 'jc/maint-remove-renamed-ref'
[git/git.git] / refs.c
1 #include "cache.h"
2 #include "refs.h"
3 #include "object.h"
4 #include "tag.h"
5 #include "dir.h"
6
7 /* ISSYMREF=01 and ISPACKED=02 are public interfaces */
8 #define REF_KNOWS_PEELED 04
9 #define REF_BROKEN 010
10
11 struct ref_entry {
12 unsigned char flag; /* ISSYMREF? ISPACKED? */
13 unsigned char sha1[20];
14 unsigned char peeled[20];
15 char name[FLEX_ARRAY];
16 };
17
18 struct ref_array {
19 int nr, alloc;
20 struct ref_entry **refs;
21 };
22
23 static const char *parse_ref_line(char *line, unsigned char *sha1)
24 {
25 /*
26 * 42: the answer to everything.
27 *
28 * In this case, it happens to be the answer to
29 * 40 (length of sha1 hex representation)
30 * +1 (space in between hex and name)
31 * +1 (newline at the end of the line)
32 */
33 int len = strlen(line) - 42;
34
35 if (len <= 0)
36 return NULL;
37 if (get_sha1_hex(line, sha1) < 0)
38 return NULL;
39 if (!isspace(line[40]))
40 return NULL;
41 line += 41;
42 if (isspace(*line))
43 return NULL;
44 if (line[len] != '\n')
45 return NULL;
46 line[len] = 0;
47
48 return line;
49 }
50
51 static void add_ref(const char *name, const unsigned char *sha1,
52 int flag, struct ref_array *refs,
53 struct ref_entry **new_entry)
54 {
55 int len;
56 struct ref_entry *entry;
57
58 /* Allocate it and add it in.. */
59 len = strlen(name) + 1;
60 entry = xmalloc(sizeof(struct ref_entry) + len);
61 hashcpy(entry->sha1, sha1);
62 hashclr(entry->peeled);
63 if (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 cached_refs {
138 struct cached_refs *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 } *cached_refs;
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_cached_refs(struct cached_refs *ca)
162 {
163 if (ca->did_loose)
164 free_ref_array(&ca->loose);
165 if (ca->did_packed)
166 free_ref_array(&ca->packed);
167 ca->did_loose = ca->did_packed = 0;
168 }
169
170 static struct cached_refs *create_cached_refs(const char *submodule)
171 {
172 int len;
173 struct cached_refs *refs;
174 if (!submodule)
175 submodule = "";
176 len = strlen(submodule) + 1;
177 refs = xcalloc(1, sizeof(struct cached_refs) + len);
178 memcpy(refs->name, submodule, len);
179 return refs;
180 }
181
182 /*
183 * Return a pointer to a cached_refs for the specified submodule. For
184 * the main repository, use submodule==NULL. The returned structure
185 * will be allocated and initialized but not necessarily populated; it
186 * should not be freed.
187 */
188 static struct cached_refs *get_cached_refs(const char *submodule)
189 {
190 struct cached_refs *refs = cached_refs;
191 if (!submodule)
192 submodule = "";
193 while (refs) {
194 if (!strcmp(submodule, refs->name))
195 return refs;
196 refs = refs->next;
197 }
198
199 refs = create_cached_refs(submodule);
200 refs->next = cached_refs;
201 cached_refs = refs;
202 return refs;
203 }
204
205 static void invalidate_cached_refs(void)
206 {
207 struct cached_refs *refs = cached_refs;
208 while (refs) {
209 clear_cached_refs(refs);
210 refs = refs->next;
211 }
212 }
213
214 static void read_packed_refs(FILE *f, struct ref_array *array)
215 {
216 struct ref_entry *last = NULL;
217 char refline[PATH_MAX];
218 int flag = REF_ISPACKED;
219
220 while (fgets(refline, sizeof(refline), f)) {
221 unsigned char sha1[20];
222 const char *name;
223 static const char header[] = "# pack-refs with:";
224
225 if (!strncmp(refline, header, sizeof(header)-1)) {
226 const char *traits = refline + sizeof(header) - 1;
227 if (strstr(traits, " peeled "))
228 flag |= REF_KNOWS_PEELED;
229 /* perhaps other traits later as well */
230 continue;
231 }
232
233 name = parse_ref_line(refline, sha1);
234 if (name) {
235 add_ref(name, sha1, flag, array, &last);
236 continue;
237 }
238 if (last &&
239 refline[0] == '^' &&
240 strlen(refline) == 42 &&
241 refline[41] == '\n' &&
242 !get_sha1_hex(refline + 1, sha1))
243 hashcpy(last->peeled, sha1);
244 }
245 sort_ref_array(array);
246 }
247
248 void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
249 {
250 add_ref(name, sha1, flag, &extra_refs, NULL);
251 }
252
253 void clear_extra_refs(void)
254 {
255 free_ref_array(&extra_refs);
256 }
257
258 static struct ref_array *get_packed_refs(const char *submodule)
259 {
260 struct cached_refs *refs = get_cached_refs(submodule);
261
262 if (!refs->did_packed) {
263 const char *packed_refs_file;
264 FILE *f;
265
266 if (submodule)
267 packed_refs_file = git_path_submodule(submodule, "packed-refs");
268 else
269 packed_refs_file = git_path("packed-refs");
270 f = fopen(packed_refs_file, "r");
271 if (f) {
272 read_packed_refs(f, &refs->packed);
273 fclose(f);
274 }
275 refs->did_packed = 1;
276 }
277 return &refs->packed;
278 }
279
280 static void get_ref_dir(const char *submodule, const char *base,
281 struct ref_array *array)
282 {
283 DIR *dir;
284 const char *path;
285
286 if (submodule)
287 path = git_path_submodule(submodule, "%s", base);
288 else
289 path = git_path("%s", base);
290
291
292 dir = opendir(path);
293
294 if (dir) {
295 struct dirent *de;
296 int baselen = strlen(base);
297 char *ref = xmalloc(baselen + 257);
298
299 memcpy(ref, base, baselen);
300 if (baselen && base[baselen-1] != '/')
301 ref[baselen++] = '/';
302
303 while ((de = readdir(dir)) != NULL) {
304 unsigned char sha1[20];
305 struct stat st;
306 int flag;
307 int namelen;
308 const char *refdir;
309
310 if (de->d_name[0] == '.')
311 continue;
312 namelen = strlen(de->d_name);
313 if (namelen > 255)
314 continue;
315 if (has_extension(de->d_name, ".lock"))
316 continue;
317 memcpy(ref + baselen, de->d_name, namelen+1);
318 refdir = submodule
319 ? git_path_submodule(submodule, "%s", ref)
320 : git_path("%s", ref);
321 if (stat(refdir, &st) < 0)
322 continue;
323 if (S_ISDIR(st.st_mode)) {
324 get_ref_dir(submodule, ref, array);
325 continue;
326 }
327 if (submodule) {
328 hashclr(sha1);
329 flag = 0;
330 if (resolve_gitlink_ref(submodule, ref, sha1) < 0) {
331 hashclr(sha1);
332 flag |= REF_BROKEN;
333 }
334 } else
335 if (!resolve_ref(ref, sha1, 1, &flag)) {
336 hashclr(sha1);
337 flag |= REF_BROKEN;
338 }
339 add_ref(ref, sha1, flag, array, NULL);
340 }
341 free(ref);
342 closedir(dir);
343 }
344 }
345
346 struct warn_if_dangling_data {
347 FILE *fp;
348 const char *refname;
349 const char *msg_fmt;
350 };
351
352 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
353 int flags, void *cb_data)
354 {
355 struct warn_if_dangling_data *d = cb_data;
356 const char *resolves_to;
357 unsigned char junk[20];
358
359 if (!(flags & REF_ISSYMREF))
360 return 0;
361
362 resolves_to = resolve_ref(refname, junk, 0, NULL);
363 if (!resolves_to || strcmp(resolves_to, d->refname))
364 return 0;
365
366 fprintf(d->fp, d->msg_fmt, refname);
367 return 0;
368 }
369
370 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
371 {
372 struct warn_if_dangling_data data;
373
374 data.fp = fp;
375 data.refname = refname;
376 data.msg_fmt = msg_fmt;
377 for_each_rawref(warn_if_dangling_symref, &data);
378 }
379
380 static struct ref_array *get_loose_refs(const char *submodule)
381 {
382 struct cached_refs *refs = get_cached_refs(submodule);
383
384 if (!refs->did_loose) {
385 get_ref_dir(submodule, "refs", &refs->loose);
386 sort_ref_array(&refs->loose);
387 refs->did_loose = 1;
388 }
389 return &refs->loose;
390 }
391
392 /* We allow "recursive" symbolic refs. Only within reason, though */
393 #define MAXDEPTH 5
394 #define MAXREFLEN (1024)
395
396 /*
397 * Called by resolve_gitlink_ref_recursive() after it failed to read
398 * from "name", which is "module/.git/<refname>". Find <refname> in
399 * the packed-refs file for the submodule.
400 */
401 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
402 {
403 int retval = -1;
404 struct ref_entry *ref;
405 struct ref_array *array;
406
407 /* being defensive: resolve_gitlink_ref() did this for us */
408 if (pathlen < 6 || memcmp(name + pathlen - 6, "/.git/", 6))
409 die("Oops");
410 name[pathlen - 6] = '\0'; /* make it path to the submodule */
411 array = get_packed_refs(name);
412 ref = search_ref_array(array, refname);
413 if (ref != NULL) {
414 memcpy(result, ref->sha1, 20);
415 retval = 0;
416 }
417 return retval;
418 }
419
420 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
421 {
422 int fd, len = strlen(refname);
423 char buffer[128], *p;
424
425 if (recursion > MAXDEPTH || len > MAXREFLEN)
426 return -1;
427 memcpy(name + pathlen, refname, len+1);
428 fd = open(name, O_RDONLY);
429 if (fd < 0)
430 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
431
432 len = read(fd, buffer, sizeof(buffer)-1);
433 close(fd);
434 if (len < 0)
435 return -1;
436 while (len && isspace(buffer[len-1]))
437 len--;
438 buffer[len] = 0;
439
440 /* Was it a detached head or an old-fashioned symlink? */
441 if (!get_sha1_hex(buffer, result))
442 return 0;
443
444 /* Symref? */
445 if (strncmp(buffer, "ref:", 4))
446 return -1;
447 p = buffer + 4;
448 while (isspace(*p))
449 p++;
450
451 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
452 }
453
454 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
455 {
456 int len = strlen(path), retval;
457 char *gitdir;
458 const char *tmp;
459
460 while (len && path[len-1] == '/')
461 len--;
462 if (!len)
463 return -1;
464 gitdir = xmalloc(len + MAXREFLEN + 8);
465 memcpy(gitdir, path, len);
466 memcpy(gitdir + len, "/.git", 6);
467 len += 5;
468
469 tmp = read_gitfile(gitdir);
470 if (tmp) {
471 free(gitdir);
472 len = strlen(tmp);
473 gitdir = xmalloc(len + MAXREFLEN + 3);
474 memcpy(gitdir, tmp, len);
475 }
476 gitdir[len] = '/';
477 gitdir[++len] = '\0';
478 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
479 free(gitdir);
480 return retval;
481 }
482
483 /*
484 * Try to read ref from the packed references. On success, set sha1
485 * and return 0; otherwise, return -1.
486 */
487 static int get_packed_ref(const char *ref, unsigned char *sha1)
488 {
489 struct ref_array *packed = get_packed_refs(NULL);
490 struct ref_entry *entry = search_ref_array(packed, ref);
491 if (entry) {
492 hashcpy(sha1, entry->sha1);
493 return 0;
494 }
495 return -1;
496 }
497
498 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
499 {
500 int depth = MAXDEPTH;
501 ssize_t len;
502 char buffer[256];
503 static char ref_buffer[256];
504 char path[PATH_MAX];
505
506 if (flag)
507 *flag = 0;
508
509 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
510 return NULL;
511
512 for (;;) {
513 struct stat st;
514 char *buf;
515 int fd;
516
517 if (--depth < 0)
518 return NULL;
519
520 git_snpath(path, sizeof(path), "%s", ref);
521
522 if (lstat(path, &st) < 0) {
523 if (errno != ENOENT)
524 return NULL;
525 /*
526 * The loose reference file does not exist;
527 * check for a packed reference.
528 */
529 if (!get_packed_ref(ref, sha1)) {
530 if (flag)
531 *flag |= REF_ISPACKED;
532 return ref;
533 }
534 /* The reference is not a packed reference, either. */
535 if (reading) {
536 return NULL;
537 } else {
538 hashclr(sha1);
539 return ref;
540 }
541 }
542
543 /* Follow "normalized" - ie "refs/.." symlinks by hand */
544 if (S_ISLNK(st.st_mode)) {
545 len = readlink(path, buffer, sizeof(buffer)-1);
546 if (len < 0)
547 return NULL;
548 buffer[len] = 0;
549 if (!prefixcmp(buffer, "refs/") &&
550 !check_refname_format(buffer, 0)) {
551 strcpy(ref_buffer, buffer);
552 ref = ref_buffer;
553 if (flag)
554 *flag |= REF_ISSYMREF;
555 continue;
556 }
557 }
558
559 /* Is it a directory? */
560 if (S_ISDIR(st.st_mode)) {
561 errno = EISDIR;
562 return NULL;
563 }
564
565 /*
566 * Anything else, just open it and try to use it as
567 * a ref
568 */
569 fd = open(path, O_RDONLY);
570 if (fd < 0)
571 return NULL;
572 len = read_in_full(fd, buffer, sizeof(buffer)-1);
573 close(fd);
574 if (len < 0)
575 return NULL;
576 while (len && isspace(buffer[len-1]))
577 len--;
578 buffer[len] = '\0';
579
580 /*
581 * Is it a symbolic ref?
582 */
583 if (prefixcmp(buffer, "ref:"))
584 break;
585 buf = buffer + 4;
586 while (isspace(*buf))
587 buf++;
588 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
589 warning("symbolic reference in %s is formatted incorrectly",
590 path);
591 return NULL;
592 }
593 ref = strcpy(ref_buffer, buf);
594 if (flag)
595 *flag |= REF_ISSYMREF;
596 }
597 /* Please note that FETCH_HEAD has a second line containing other data. */
598 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
599 warning("reference in %s is formatted incorrectly", path);
600 return NULL;
601 }
602 return ref;
603 }
604
605 /* The argument to filter_refs */
606 struct ref_filter {
607 const char *pattern;
608 each_ref_fn *fn;
609 void *cb_data;
610 };
611
612 int read_ref(const char *ref, unsigned char *sha1)
613 {
614 if (resolve_ref(ref, sha1, 1, NULL))
615 return 0;
616 return -1;
617 }
618
619 #define DO_FOR_EACH_INCLUDE_BROKEN 01
620 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
621 int flags, void *cb_data, struct ref_entry *entry)
622 {
623 if (prefixcmp(entry->name, base))
624 return 0;
625
626 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
627 if (entry->flag & REF_BROKEN)
628 return 0; /* ignore dangling symref */
629 if (!has_sha1_file(entry->sha1)) {
630 error("%s does not point to a valid object!", entry->name);
631 return 0;
632 }
633 }
634 current_ref = entry;
635 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
636 }
637
638 static int filter_refs(const char *ref, const unsigned char *sha, int flags,
639 void *data)
640 {
641 struct ref_filter *filter = (struct ref_filter *)data;
642 if (fnmatch(filter->pattern, ref, 0))
643 return 0;
644 return filter->fn(ref, sha, flags, filter->cb_data);
645 }
646
647 int peel_ref(const char *ref, unsigned char *sha1)
648 {
649 int flag;
650 unsigned char base[20];
651 struct object *o;
652
653 if (current_ref && (current_ref->name == ref
654 || !strcmp(current_ref->name, ref))) {
655 if (current_ref->flag & REF_KNOWS_PEELED) {
656 hashcpy(sha1, current_ref->peeled);
657 return 0;
658 }
659 hashcpy(base, current_ref->sha1);
660 goto fallback;
661 }
662
663 if (!resolve_ref(ref, base, 1, &flag))
664 return -1;
665
666 if ((flag & REF_ISPACKED)) {
667 struct ref_array *array = get_packed_refs(NULL);
668 struct ref_entry *r = search_ref_array(array, ref);
669
670 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
671 hashcpy(sha1, r->peeled);
672 return 0;
673 }
674 }
675
676 fallback:
677 o = parse_object(base);
678 if (o && o->type == OBJ_TAG) {
679 o = deref_tag(o, ref, 0);
680 if (o) {
681 hashcpy(sha1, o->sha1);
682 return 0;
683 }
684 }
685 return -1;
686 }
687
688 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
689 int trim, int flags, void *cb_data)
690 {
691 int retval = 0, i, p = 0, l = 0;
692 struct ref_array *packed = get_packed_refs(submodule);
693 struct ref_array *loose = get_loose_refs(submodule);
694
695 struct ref_array *extra = &extra_refs;
696
697 for (i = 0; i < extra->nr; i++)
698 retval = do_one_ref(base, fn, trim, flags, cb_data, extra->refs[i]);
699
700 while (p < packed->nr && l < loose->nr) {
701 struct ref_entry *entry;
702 int cmp = strcmp(packed->refs[p]->name, loose->refs[l]->name);
703 if (!cmp) {
704 p++;
705 continue;
706 }
707 if (cmp > 0) {
708 entry = loose->refs[l++];
709 } else {
710 entry = packed->refs[p++];
711 }
712 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
713 if (retval)
714 goto end_each;
715 }
716
717 if (l < loose->nr) {
718 p = l;
719 packed = loose;
720 }
721
722 for (; p < packed->nr; p++) {
723 retval = do_one_ref(base, fn, trim, flags, cb_data, packed->refs[p]);
724 if (retval)
725 goto end_each;
726 }
727
728 end_each:
729 current_ref = NULL;
730 return retval;
731 }
732
733
734 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
735 {
736 unsigned char sha1[20];
737 int flag;
738
739 if (submodule) {
740 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
741 return fn("HEAD", sha1, 0, cb_data);
742
743 return 0;
744 }
745
746 if (resolve_ref("HEAD", sha1, 1, &flag))
747 return fn("HEAD", sha1, flag, cb_data);
748
749 return 0;
750 }
751
752 int head_ref(each_ref_fn fn, void *cb_data)
753 {
754 return do_head_ref(NULL, fn, cb_data);
755 }
756
757 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
758 {
759 return do_head_ref(submodule, fn, cb_data);
760 }
761
762 int for_each_ref(each_ref_fn fn, void *cb_data)
763 {
764 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
765 }
766
767 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
768 {
769 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
770 }
771
772 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
773 {
774 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
775 }
776
777 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
778 each_ref_fn fn, void *cb_data)
779 {
780 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
781 }
782
783 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
784 {
785 return for_each_ref_in("refs/tags/", fn, cb_data);
786 }
787
788 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
789 {
790 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
791 }
792
793 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
794 {
795 return for_each_ref_in("refs/heads/", fn, cb_data);
796 }
797
798 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
799 {
800 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
801 }
802
803 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
804 {
805 return for_each_ref_in("refs/remotes/", fn, cb_data);
806 }
807
808 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
809 {
810 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
811 }
812
813 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
814 {
815 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
816 }
817
818 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
819 {
820 struct strbuf buf = STRBUF_INIT;
821 int ret = 0;
822 unsigned char sha1[20];
823 int flag;
824
825 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
826 if (resolve_ref(buf.buf, sha1, 1, &flag))
827 ret = fn(buf.buf, sha1, flag, cb_data);
828 strbuf_release(&buf);
829
830 return ret;
831 }
832
833 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
834 {
835 struct strbuf buf = STRBUF_INIT;
836 int ret;
837 strbuf_addf(&buf, "%srefs/", get_git_namespace());
838 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
839 strbuf_release(&buf);
840 return ret;
841 }
842
843 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
844 const char *prefix, void *cb_data)
845 {
846 struct strbuf real_pattern = STRBUF_INIT;
847 struct ref_filter filter;
848 int ret;
849
850 if (!prefix && prefixcmp(pattern, "refs/"))
851 strbuf_addstr(&real_pattern, "refs/");
852 else if (prefix)
853 strbuf_addstr(&real_pattern, prefix);
854 strbuf_addstr(&real_pattern, pattern);
855
856 if (!has_glob_specials(pattern)) {
857 /* Append implied '/' '*' if not present. */
858 if (real_pattern.buf[real_pattern.len - 1] != '/')
859 strbuf_addch(&real_pattern, '/');
860 /* No need to check for '*', there is none. */
861 strbuf_addch(&real_pattern, '*');
862 }
863
864 filter.pattern = real_pattern.buf;
865 filter.fn = fn;
866 filter.cb_data = cb_data;
867 ret = for_each_ref(filter_refs, &filter);
868
869 strbuf_release(&real_pattern);
870 return ret;
871 }
872
873 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
874 {
875 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
876 }
877
878 int for_each_rawref(each_ref_fn fn, void *cb_data)
879 {
880 return do_for_each_ref(NULL, "", fn, 0,
881 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
882 }
883
884 /*
885 * Make sure "ref" is something reasonable to have under ".git/refs/";
886 * We do not like it if:
887 *
888 * - any path component of it begins with ".", or
889 * - it has double dots "..", or
890 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
891 * - it ends with a "/".
892 * - it ends with ".lock"
893 * - it contains a "\" (backslash)
894 */
895
896 /* Return true iff ch is not allowed in reference names. */
897 static inline int bad_ref_char(int ch)
898 {
899 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
900 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
901 return 1;
902 /* 2.13 Pattern Matching Notation */
903 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
904 return 1;
905 return 0;
906 }
907
908 /*
909 * Try to read one refname component from the front of ref. Return
910 * the length of the component found, or -1 if the component is not
911 * legal.
912 */
913 static int check_refname_component(const char *ref, int flags)
914 {
915 const char *cp;
916 char last = '\0';
917
918 for (cp = ref; ; cp++) {
919 char ch = *cp;
920 if (ch == '\0' || ch == '/')
921 break;
922 if (bad_ref_char(ch))
923 return -1; /* Illegal character in refname. */
924 if (last == '.' && ch == '.')
925 return -1; /* Refname contains "..". */
926 if (last == '@' && ch == '{')
927 return -1; /* Refname contains "@{". */
928 last = ch;
929 }
930 if (cp == ref)
931 return -1; /* Component has zero length. */
932 if (ref[0] == '.') {
933 if (!(flags & REFNAME_DOT_COMPONENT))
934 return -1; /* Component starts with '.'. */
935 /*
936 * Even if leading dots are allowed, don't allow "."
937 * as a component (".." is prevented by a rule above).
938 */
939 if (ref[1] == '\0')
940 return -1; /* Component equals ".". */
941 }
942 if (cp - ref >= 5 && !memcmp(cp - 5, ".lock", 5))
943 return -1; /* Refname ends with ".lock". */
944 return cp - ref;
945 }
946
947 int check_refname_format(const char *ref, int flags)
948 {
949 int component_len, component_count = 0;
950
951 while (1) {
952 /* We are at the start of a path component. */
953 component_len = check_refname_component(ref, flags);
954 if (component_len < 0) {
955 if ((flags & REFNAME_REFSPEC_PATTERN) &&
956 ref[0] == '*' &&
957 (ref[1] == '\0' || ref[1] == '/')) {
958 /* Accept one wildcard as a full refname component. */
959 flags &= ~REFNAME_REFSPEC_PATTERN;
960 component_len = 1;
961 } else {
962 return -1;
963 }
964 }
965 component_count++;
966 if (ref[component_len] == '\0')
967 break;
968 /* Skip to next component. */
969 ref += component_len + 1;
970 }
971
972 if (ref[component_len - 1] == '.')
973 return -1; /* Refname ends with '.'. */
974 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
975 return -1; /* Refname has only one component. */
976 return 0;
977 }
978
979 const char *prettify_refname(const char *name)
980 {
981 return name + (
982 !prefixcmp(name, "refs/heads/") ? 11 :
983 !prefixcmp(name, "refs/tags/") ? 10 :
984 !prefixcmp(name, "refs/remotes/") ? 13 :
985 0);
986 }
987
988 const char *ref_rev_parse_rules[] = {
989 "%.*s",
990 "refs/%.*s",
991 "refs/tags/%.*s",
992 "refs/heads/%.*s",
993 "refs/remotes/%.*s",
994 "refs/remotes/%.*s/HEAD",
995 NULL
996 };
997
998 const char *ref_fetch_rules[] = {
999 "%.*s",
1000 "refs/%.*s",
1001 "refs/heads/%.*s",
1002 NULL
1003 };
1004
1005 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1006 {
1007 const char **p;
1008 const int abbrev_name_len = strlen(abbrev_name);
1009
1010 for (p = rules; *p; p++) {
1011 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1012 return 1;
1013 }
1014 }
1015
1016 return 0;
1017 }
1018
1019 static struct ref_lock *verify_lock(struct ref_lock *lock,
1020 const unsigned char *old_sha1, int mustexist)
1021 {
1022 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
1023 error("Can't verify ref %s", lock->ref_name);
1024 unlock_ref(lock);
1025 return NULL;
1026 }
1027 if (hashcmp(lock->old_sha1, old_sha1)) {
1028 error("Ref %s is at %s but expected %s", lock->ref_name,
1029 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1030 unlock_ref(lock);
1031 return NULL;
1032 }
1033 return lock;
1034 }
1035
1036 static int remove_empty_directories(const char *file)
1037 {
1038 /* we want to create a file but there is a directory there;
1039 * if that is an empty directory (or a directory that contains
1040 * only empty directories), remove them.
1041 */
1042 struct strbuf path;
1043 int result;
1044
1045 strbuf_init(&path, 20);
1046 strbuf_addstr(&path, file);
1047
1048 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1049
1050 strbuf_release(&path);
1051
1052 return result;
1053 }
1054
1055 static int is_refname_available(const char *ref, const char *oldref,
1056 struct ref_array *array, int quiet)
1057 {
1058 int i, namlen = strlen(ref); /* e.g. 'foo/bar' */
1059 for (i = 0; i < array->nr; i++ ) {
1060 struct ref_entry *entry = array->refs[i];
1061 /* entry->name could be 'foo' or 'foo/bar/baz' */
1062 if (!oldref || strcmp(oldref, entry->name)) {
1063 int len = strlen(entry->name);
1064 int cmplen = (namlen < len) ? namlen : len;
1065 const char *lead = (namlen < len) ? entry->name : ref;
1066 if (!strncmp(ref, entry->name, cmplen) &&
1067 lead[cmplen] == '/') {
1068 if (!quiet)
1069 error("'%s' exists; cannot create '%s'",
1070 entry->name, ref);
1071 return 0;
1072 }
1073 }
1074 }
1075 return 1;
1076 }
1077
1078 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
1079 {
1080 char *ref_file;
1081 const char *orig_ref = ref;
1082 struct ref_lock *lock;
1083 int last_errno = 0;
1084 int type, lflags;
1085 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1086 int missing = 0;
1087
1088 lock = xcalloc(1, sizeof(struct ref_lock));
1089 lock->lock_fd = -1;
1090
1091 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
1092 if (!ref && errno == EISDIR) {
1093 /* we are trying to lock foo but we used to
1094 * have foo/bar which now does not exist;
1095 * it is normal for the empty directory 'foo'
1096 * to remain.
1097 */
1098 ref_file = git_path("%s", orig_ref);
1099 if (remove_empty_directories(ref_file)) {
1100 last_errno = errno;
1101 error("there are still refs under '%s'", orig_ref);
1102 goto error_return;
1103 }
1104 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
1105 }
1106 if (type_p)
1107 *type_p = type;
1108 if (!ref) {
1109 last_errno = errno;
1110 error("unable to resolve reference %s: %s",
1111 orig_ref, strerror(errno));
1112 goto error_return;
1113 }
1114 missing = is_null_sha1(lock->old_sha1);
1115 /* When the ref did not exist and we are creating it,
1116 * make sure there is no existing ref that is packed
1117 * whose name begins with our refname, nor a ref whose
1118 * name is a proper prefix of our refname.
1119 */
1120 if (missing &&
1121 !is_refname_available(ref, NULL, get_packed_refs(NULL), 0)) {
1122 last_errno = ENOTDIR;
1123 goto error_return;
1124 }
1125
1126 lock->lk = xcalloc(1, sizeof(struct lock_file));
1127
1128 lflags = LOCK_DIE_ON_ERROR;
1129 if (flags & REF_NODEREF) {
1130 ref = orig_ref;
1131 lflags |= LOCK_NODEREF;
1132 }
1133 lock->ref_name = xstrdup(ref);
1134 lock->orig_ref_name = xstrdup(orig_ref);
1135 ref_file = git_path("%s", ref);
1136 if (missing)
1137 lock->force_write = 1;
1138 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1139 lock->force_write = 1;
1140
1141 if (safe_create_leading_directories(ref_file)) {
1142 last_errno = errno;
1143 error("unable to create directory for %s", ref_file);
1144 goto error_return;
1145 }
1146
1147 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1148 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1149
1150 error_return:
1151 unlock_ref(lock);
1152 errno = last_errno;
1153 return NULL;
1154 }
1155
1156 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
1157 {
1158 char refpath[PATH_MAX];
1159 if (check_refname_format(ref, 0))
1160 return NULL;
1161 strcpy(refpath, mkpath("refs/%s", ref));
1162 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1163 }
1164
1165 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
1166 {
1167 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
1168 return NULL;
1169 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1170 }
1171
1172 static struct lock_file packlock;
1173
1174 static int repack_without_ref(const char *refname)
1175 {
1176 struct ref_array *packed;
1177 struct ref_entry *ref;
1178 int fd, i;
1179
1180 packed = get_packed_refs(NULL);
1181 ref = search_ref_array(packed, refname);
1182 if (ref == NULL)
1183 return 0;
1184 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1185 if (fd < 0) {
1186 unable_to_lock_error(git_path("packed-refs"), errno);
1187 return error("cannot delete '%s' from packed refs", refname);
1188 }
1189
1190 for (i = 0; i < packed->nr; i++) {
1191 char line[PATH_MAX + 100];
1192 int len;
1193
1194 ref = packed->refs[i];
1195
1196 if (!strcmp(refname, ref->name))
1197 continue;
1198 len = snprintf(line, sizeof(line), "%s %s\n",
1199 sha1_to_hex(ref->sha1), ref->name);
1200 /* this should not happen but just being defensive */
1201 if (len > sizeof(line))
1202 die("too long a refname '%s'", ref->name);
1203 write_or_die(fd, line, len);
1204 }
1205 return commit_lock_file(&packlock);
1206 }
1207
1208 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1209 {
1210 struct ref_lock *lock;
1211 int err, i = 0, ret = 0, flag = 0;
1212
1213 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1214 if (!lock)
1215 return 1;
1216 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1217 /* loose */
1218 const char *path;
1219
1220 if (!(delopt & REF_NODEREF)) {
1221 i = strlen(lock->lk->filename) - 5; /* .lock */
1222 lock->lk->filename[i] = 0;
1223 path = lock->lk->filename;
1224 } else {
1225 path = git_path("%s", refname);
1226 }
1227 err = unlink_or_warn(path);
1228 if (err && errno != ENOENT)
1229 ret = 1;
1230
1231 if (!(delopt & REF_NODEREF))
1232 lock->lk->filename[i] = '.';
1233 }
1234 /* removing the loose one could have resurrected an earlier
1235 * packed one. Also, if it was not loose we need to repack
1236 * without it.
1237 */
1238 ret |= repack_without_ref(refname);
1239
1240 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1241 invalidate_cached_refs();
1242 unlock_ref(lock);
1243 return ret;
1244 }
1245
1246 /*
1247 * People using contrib's git-new-workdir have .git/logs/refs ->
1248 * /some/other/path/.git/logs/refs, and that may live on another device.
1249 *
1250 * IOW, to avoid cross device rename errors, the temporary renamed log must
1251 * live into logs/refs.
1252 */
1253 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1254
1255 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1256 {
1257 unsigned char sha1[20], orig_sha1[20];
1258 int flag = 0, logmoved = 0;
1259 struct ref_lock *lock;
1260 struct stat loginfo;
1261 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1262 const char *symref = NULL;
1263
1264 if (log && S_ISLNK(loginfo.st_mode))
1265 return error("reflog for %s is a symlink", oldref);
1266
1267 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1268 if (flag & REF_ISSYMREF)
1269 return error("refname %s is a symbolic ref, renaming it is not supported",
1270 oldref);
1271 if (!symref)
1272 return error("refname %s not found", oldref);
1273
1274 if (!is_refname_available(newref, oldref, get_packed_refs(NULL), 0))
1275 return 1;
1276
1277 if (!is_refname_available(newref, oldref, get_loose_refs(NULL), 0))
1278 return 1;
1279
1280 if (log && rename(git_path("logs/%s", oldref), git_path(TMP_RENAMED_LOG)))
1281 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1282 oldref, strerror(errno));
1283
1284 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1285 error("unable to delete old %s", oldref);
1286 goto rollback;
1287 }
1288
1289 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1290 if (errno==EISDIR) {
1291 if (remove_empty_directories(git_path("%s", newref))) {
1292 error("Directory not empty: %s", newref);
1293 goto rollback;
1294 }
1295 } else {
1296 error("unable to delete existing %s", newref);
1297 goto rollback;
1298 }
1299 }
1300
1301 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1302 error("unable to create directory for %s", newref);
1303 goto rollback;
1304 }
1305
1306 retry:
1307 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newref))) {
1308 if (errno==EISDIR || errno==ENOTDIR) {
1309 /*
1310 * rename(a, b) when b is an existing
1311 * directory ought to result in ISDIR, but
1312 * Solaris 5.8 gives ENOTDIR. Sheesh.
1313 */
1314 if (remove_empty_directories(git_path("logs/%s", newref))) {
1315 error("Directory not empty: logs/%s", newref);
1316 goto rollback;
1317 }
1318 goto retry;
1319 } else {
1320 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1321 newref, strerror(errno));
1322 goto rollback;
1323 }
1324 }
1325 logmoved = log;
1326
1327 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1328 if (!lock) {
1329 error("unable to lock %s for update", newref);
1330 goto rollback;
1331 }
1332 lock->force_write = 1;
1333 hashcpy(lock->old_sha1, orig_sha1);
1334 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1335 error("unable to write current sha1 into %s", newref);
1336 goto rollback;
1337 }
1338
1339 return 0;
1340
1341 rollback:
1342 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1343 if (!lock) {
1344 error("unable to lock %s for rollback", oldref);
1345 goto rollbacklog;
1346 }
1347
1348 lock->force_write = 1;
1349 flag = log_all_ref_updates;
1350 log_all_ref_updates = 0;
1351 if (write_ref_sha1(lock, orig_sha1, NULL))
1352 error("unable to write current sha1 into %s", oldref);
1353 log_all_ref_updates = flag;
1354
1355 rollbacklog:
1356 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1357 error("unable to restore logfile %s from %s: %s",
1358 oldref, newref, strerror(errno));
1359 if (!logmoved && log &&
1360 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldref)))
1361 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1362 oldref, strerror(errno));
1363
1364 return 1;
1365 }
1366
1367 int close_ref(struct ref_lock *lock)
1368 {
1369 if (close_lock_file(lock->lk))
1370 return -1;
1371 lock->lock_fd = -1;
1372 return 0;
1373 }
1374
1375 int commit_ref(struct ref_lock *lock)
1376 {
1377 if (commit_lock_file(lock->lk))
1378 return -1;
1379 lock->lock_fd = -1;
1380 return 0;
1381 }
1382
1383 void unlock_ref(struct ref_lock *lock)
1384 {
1385 /* Do not free lock->lk -- atexit() still looks at them */
1386 if (lock->lk)
1387 rollback_lock_file(lock->lk);
1388 free(lock->ref_name);
1389 free(lock->orig_ref_name);
1390 free(lock);
1391 }
1392
1393 /*
1394 * copy the reflog message msg to buf, which has been allocated sufficiently
1395 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1396 * because reflog file is one line per entry.
1397 */
1398 static int copy_msg(char *buf, const char *msg)
1399 {
1400 char *cp = buf;
1401 char c;
1402 int wasspace = 1;
1403
1404 *cp++ = '\t';
1405 while ((c = *msg++)) {
1406 if (wasspace && isspace(c))
1407 continue;
1408 wasspace = isspace(c);
1409 if (wasspace)
1410 c = ' ';
1411 *cp++ = c;
1412 }
1413 while (buf < cp && isspace(cp[-1]))
1414 cp--;
1415 *cp++ = '\n';
1416 return cp - buf;
1417 }
1418
1419 int log_ref_setup(const char *ref_name, char *logfile, int bufsize)
1420 {
1421 int logfd, oflags = O_APPEND | O_WRONLY;
1422
1423 git_snpath(logfile, bufsize, "logs/%s", ref_name);
1424 if (log_all_ref_updates &&
1425 (!prefixcmp(ref_name, "refs/heads/") ||
1426 !prefixcmp(ref_name, "refs/remotes/") ||
1427 !prefixcmp(ref_name, "refs/notes/") ||
1428 !strcmp(ref_name, "HEAD"))) {
1429 if (safe_create_leading_directories(logfile) < 0)
1430 return error("unable to create directory for %s",
1431 logfile);
1432 oflags |= O_CREAT;
1433 }
1434
1435 logfd = open(logfile, oflags, 0666);
1436 if (logfd < 0) {
1437 if (!(oflags & O_CREAT) && errno == ENOENT)
1438 return 0;
1439
1440 if ((oflags & O_CREAT) && errno == EISDIR) {
1441 if (remove_empty_directories(logfile)) {
1442 return error("There are still logs under '%s'",
1443 logfile);
1444 }
1445 logfd = open(logfile, oflags, 0666);
1446 }
1447
1448 if (logfd < 0)
1449 return error("Unable to append to %s: %s",
1450 logfile, strerror(errno));
1451 }
1452
1453 adjust_shared_perm(logfile);
1454 close(logfd);
1455 return 0;
1456 }
1457
1458 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1459 const unsigned char *new_sha1, const char *msg)
1460 {
1461 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1462 unsigned maxlen, len;
1463 int msglen;
1464 char log_file[PATH_MAX];
1465 char *logrec;
1466 const char *committer;
1467
1468 if (log_all_ref_updates < 0)
1469 log_all_ref_updates = !is_bare_repository();
1470
1471 result = log_ref_setup(ref_name, log_file, sizeof(log_file));
1472 if (result)
1473 return result;
1474
1475 logfd = open(log_file, oflags);
1476 if (logfd < 0)
1477 return 0;
1478 msglen = msg ? strlen(msg) : 0;
1479 committer = git_committer_info(0);
1480 maxlen = strlen(committer) + msglen + 100;
1481 logrec = xmalloc(maxlen);
1482 len = sprintf(logrec, "%s %s %s\n",
1483 sha1_to_hex(old_sha1),
1484 sha1_to_hex(new_sha1),
1485 committer);
1486 if (msglen)
1487 len += copy_msg(logrec + len - 1, msg) - 1;
1488 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1489 free(logrec);
1490 if (close(logfd) != 0 || written != len)
1491 return error("Unable to append to %s", log_file);
1492 return 0;
1493 }
1494
1495 static int is_branch(const char *refname)
1496 {
1497 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1498 }
1499
1500 int write_ref_sha1(struct ref_lock *lock,
1501 const unsigned char *sha1, const char *logmsg)
1502 {
1503 static char term = '\n';
1504 struct object *o;
1505
1506 if (!lock)
1507 return -1;
1508 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1509 unlock_ref(lock);
1510 return 0;
1511 }
1512 o = parse_object(sha1);
1513 if (!o) {
1514 error("Trying to write ref %s with nonexistent object %s",
1515 lock->ref_name, sha1_to_hex(sha1));
1516 unlock_ref(lock);
1517 return -1;
1518 }
1519 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1520 error("Trying to write non-commit object %s to branch %s",
1521 sha1_to_hex(sha1), lock->ref_name);
1522 unlock_ref(lock);
1523 return -1;
1524 }
1525 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1526 write_in_full(lock->lock_fd, &term, 1) != 1
1527 || close_ref(lock) < 0) {
1528 error("Couldn't write %s", lock->lk->filename);
1529 unlock_ref(lock);
1530 return -1;
1531 }
1532 invalidate_cached_refs();
1533 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1534 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1535 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1536 unlock_ref(lock);
1537 return -1;
1538 }
1539 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1540 /*
1541 * Special hack: If a branch is updated directly and HEAD
1542 * points to it (may happen on the remote side of a push
1543 * for example) then logically the HEAD reflog should be
1544 * updated too.
1545 * A generic solution implies reverse symref information,
1546 * but finding all symrefs pointing to the given branch
1547 * would be rather costly for this rare event (the direct
1548 * update of a branch) to be worth it. So let's cheat and
1549 * check with HEAD only which should cover 99% of all usage
1550 * scenarios (even 100% of the default ones).
1551 */
1552 unsigned char head_sha1[20];
1553 int head_flag;
1554 const char *head_ref;
1555 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1556 if (head_ref && (head_flag & REF_ISSYMREF) &&
1557 !strcmp(head_ref, lock->ref_name))
1558 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1559 }
1560 if (commit_ref(lock)) {
1561 error("Couldn't set %s", lock->ref_name);
1562 unlock_ref(lock);
1563 return -1;
1564 }
1565 unlock_ref(lock);
1566 return 0;
1567 }
1568
1569 int create_symref(const char *ref_target, const char *refs_heads_master,
1570 const char *logmsg)
1571 {
1572 const char *lockpath;
1573 char ref[1000];
1574 int fd, len, written;
1575 char *git_HEAD = git_pathdup("%s", ref_target);
1576 unsigned char old_sha1[20], new_sha1[20];
1577
1578 if (logmsg && read_ref(ref_target, old_sha1))
1579 hashclr(old_sha1);
1580
1581 if (safe_create_leading_directories(git_HEAD) < 0)
1582 return error("unable to create directory for %s", git_HEAD);
1583
1584 #ifndef NO_SYMLINK_HEAD
1585 if (prefer_symlink_refs) {
1586 unlink(git_HEAD);
1587 if (!symlink(refs_heads_master, git_HEAD))
1588 goto done;
1589 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1590 }
1591 #endif
1592
1593 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1594 if (sizeof(ref) <= len) {
1595 error("refname too long: %s", refs_heads_master);
1596 goto error_free_return;
1597 }
1598 lockpath = mkpath("%s.lock", git_HEAD);
1599 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1600 if (fd < 0) {
1601 error("Unable to open %s for writing", lockpath);
1602 goto error_free_return;
1603 }
1604 written = write_in_full(fd, ref, len);
1605 if (close(fd) != 0 || written != len) {
1606 error("Unable to write to %s", lockpath);
1607 goto error_unlink_return;
1608 }
1609 if (rename(lockpath, git_HEAD) < 0) {
1610 error("Unable to create %s", git_HEAD);
1611 goto error_unlink_return;
1612 }
1613 if (adjust_shared_perm(git_HEAD)) {
1614 error("Unable to fix permissions on %s", lockpath);
1615 error_unlink_return:
1616 unlink_or_warn(lockpath);
1617 error_free_return:
1618 free(git_HEAD);
1619 return -1;
1620 }
1621
1622 #ifndef NO_SYMLINK_HEAD
1623 done:
1624 #endif
1625 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1626 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1627
1628 free(git_HEAD);
1629 return 0;
1630 }
1631
1632 static char *ref_msg(const char *line, const char *endp)
1633 {
1634 const char *ep;
1635 line += 82;
1636 ep = memchr(line, '\n', endp - line);
1637 if (!ep)
1638 ep = endp;
1639 return xmemdupz(line, ep - line);
1640 }
1641
1642 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)
1643 {
1644 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1645 char *tz_c;
1646 int logfd, tz, reccnt = 0;
1647 struct stat st;
1648 unsigned long date;
1649 unsigned char logged_sha1[20];
1650 void *log_mapped;
1651 size_t mapsz;
1652
1653 logfile = git_path("logs/%s", ref);
1654 logfd = open(logfile, O_RDONLY, 0);
1655 if (logfd < 0)
1656 die_errno("Unable to read log '%s'", logfile);
1657 fstat(logfd, &st);
1658 if (!st.st_size)
1659 die("Log %s is empty.", logfile);
1660 mapsz = xsize_t(st.st_size);
1661 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1662 logdata = log_mapped;
1663 close(logfd);
1664
1665 lastrec = NULL;
1666 rec = logend = logdata + st.st_size;
1667 while (logdata < rec) {
1668 reccnt++;
1669 if (logdata < rec && *(rec-1) == '\n')
1670 rec--;
1671 lastgt = NULL;
1672 while (logdata < rec && *(rec-1) != '\n') {
1673 rec--;
1674 if (*rec == '>')
1675 lastgt = rec;
1676 }
1677 if (!lastgt)
1678 die("Log %s is corrupt.", logfile);
1679 date = strtoul(lastgt + 1, &tz_c, 10);
1680 if (date <= at_time || cnt == 0) {
1681 tz = strtoul(tz_c, NULL, 10);
1682 if (msg)
1683 *msg = ref_msg(rec, logend);
1684 if (cutoff_time)
1685 *cutoff_time = date;
1686 if (cutoff_tz)
1687 *cutoff_tz = tz;
1688 if (cutoff_cnt)
1689 *cutoff_cnt = reccnt - 1;
1690 if (lastrec) {
1691 if (get_sha1_hex(lastrec, logged_sha1))
1692 die("Log %s is corrupt.", logfile);
1693 if (get_sha1_hex(rec + 41, sha1))
1694 die("Log %s is corrupt.", logfile);
1695 if (hashcmp(logged_sha1, sha1)) {
1696 warning("Log %s has gap after %s.",
1697 logfile, show_date(date, tz, DATE_RFC2822));
1698 }
1699 }
1700 else if (date == at_time) {
1701 if (get_sha1_hex(rec + 41, sha1))
1702 die("Log %s is corrupt.", logfile);
1703 }
1704 else {
1705 if (get_sha1_hex(rec + 41, logged_sha1))
1706 die("Log %s is corrupt.", logfile);
1707 if (hashcmp(logged_sha1, sha1)) {
1708 warning("Log %s unexpectedly ended on %s.",
1709 logfile, show_date(date, tz, DATE_RFC2822));
1710 }
1711 }
1712 munmap(log_mapped, mapsz);
1713 return 0;
1714 }
1715 lastrec = rec;
1716 if (cnt > 0)
1717 cnt--;
1718 }
1719
1720 rec = logdata;
1721 while (rec < logend && *rec != '>' && *rec != '\n')
1722 rec++;
1723 if (rec == logend || *rec == '\n')
1724 die("Log %s is corrupt.", logfile);
1725 date = strtoul(rec + 1, &tz_c, 10);
1726 tz = strtoul(tz_c, NULL, 10);
1727 if (get_sha1_hex(logdata, sha1))
1728 die("Log %s is corrupt.", logfile);
1729 if (is_null_sha1(sha1)) {
1730 if (get_sha1_hex(logdata + 41, sha1))
1731 die("Log %s is corrupt.", logfile);
1732 }
1733 if (msg)
1734 *msg = ref_msg(logdata, logend);
1735 munmap(log_mapped, mapsz);
1736
1737 if (cutoff_time)
1738 *cutoff_time = date;
1739 if (cutoff_tz)
1740 *cutoff_tz = tz;
1741 if (cutoff_cnt)
1742 *cutoff_cnt = reccnt;
1743 return 1;
1744 }
1745
1746 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1747 {
1748 const char *logfile;
1749 FILE *logfp;
1750 struct strbuf sb = STRBUF_INIT;
1751 int ret = 0;
1752
1753 logfile = git_path("logs/%s", ref);
1754 logfp = fopen(logfile, "r");
1755 if (!logfp)
1756 return -1;
1757
1758 if (ofs) {
1759 struct stat statbuf;
1760 if (fstat(fileno(logfp), &statbuf) ||
1761 statbuf.st_size < ofs ||
1762 fseek(logfp, -ofs, SEEK_END) ||
1763 strbuf_getwholeline(&sb, logfp, '\n')) {
1764 fclose(logfp);
1765 strbuf_release(&sb);
1766 return -1;
1767 }
1768 }
1769
1770 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1771 unsigned char osha1[20], nsha1[20];
1772 char *email_end, *message;
1773 unsigned long timestamp;
1774 int tz;
1775
1776 /* old SP new SP name <email> SP time TAB msg LF */
1777 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1778 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1779 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1780 !(email_end = strchr(sb.buf + 82, '>')) ||
1781 email_end[1] != ' ' ||
1782 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1783 !message || message[0] != ' ' ||
1784 (message[1] != '+' && message[1] != '-') ||
1785 !isdigit(message[2]) || !isdigit(message[3]) ||
1786 !isdigit(message[4]) || !isdigit(message[5]))
1787 continue; /* corrupt? */
1788 email_end[1] = '\0';
1789 tz = strtol(message + 1, NULL, 10);
1790 if (message[6] != '\t')
1791 message += 6;
1792 else
1793 message += 7;
1794 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1795 cb_data);
1796 if (ret)
1797 break;
1798 }
1799 fclose(logfp);
1800 strbuf_release(&sb);
1801 return ret;
1802 }
1803
1804 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1805 {
1806 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1807 }
1808
1809 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1810 {
1811 DIR *dir = opendir(git_path("logs/%s", base));
1812 int retval = 0;
1813
1814 if (dir) {
1815 struct dirent *de;
1816 int baselen = strlen(base);
1817 char *log = xmalloc(baselen + 257);
1818
1819 memcpy(log, base, baselen);
1820 if (baselen && base[baselen-1] != '/')
1821 log[baselen++] = '/';
1822
1823 while ((de = readdir(dir)) != NULL) {
1824 struct stat st;
1825 int namelen;
1826
1827 if (de->d_name[0] == '.')
1828 continue;
1829 namelen = strlen(de->d_name);
1830 if (namelen > 255)
1831 continue;
1832 if (has_extension(de->d_name, ".lock"))
1833 continue;
1834 memcpy(log + baselen, de->d_name, namelen+1);
1835 if (stat(git_path("logs/%s", log), &st) < 0)
1836 continue;
1837 if (S_ISDIR(st.st_mode)) {
1838 retval = do_for_each_reflog(log, fn, cb_data);
1839 } else {
1840 unsigned char sha1[20];
1841 if (!resolve_ref(log, sha1, 0, NULL))
1842 retval = error("bad ref for %s", log);
1843 else
1844 retval = fn(log, sha1, 0, cb_data);
1845 }
1846 if (retval)
1847 break;
1848 }
1849 free(log);
1850 closedir(dir);
1851 }
1852 else if (*base)
1853 return errno;
1854 return retval;
1855 }
1856
1857 int for_each_reflog(each_ref_fn fn, void *cb_data)
1858 {
1859 return do_for_each_reflog("", fn, cb_data);
1860 }
1861
1862 int update_ref(const char *action, const char *refname,
1863 const unsigned char *sha1, const unsigned char *oldval,
1864 int flags, enum action_on_err onerr)
1865 {
1866 static struct ref_lock *lock;
1867 lock = lock_any_ref_for_update(refname, oldval, flags);
1868 if (!lock) {
1869 const char *str = "Cannot lock the ref '%s'.";
1870 switch (onerr) {
1871 case MSG_ON_ERR: error(str, refname); break;
1872 case DIE_ON_ERR: die(str, refname); break;
1873 case QUIET_ON_ERR: break;
1874 }
1875 return 1;
1876 }
1877 if (write_ref_sha1(lock, sha1, action) < 0) {
1878 const char *str = "Cannot update the ref '%s'.";
1879 switch (onerr) {
1880 case MSG_ON_ERR: error(str, refname); break;
1881 case DIE_ON_ERR: die(str, refname); break;
1882 case QUIET_ON_ERR: break;
1883 }
1884 return 1;
1885 }
1886 return 0;
1887 }
1888
1889 int ref_exists(const char *refname)
1890 {
1891 unsigned char sha1[20];
1892 return !!resolve_ref(refname, sha1, 1, NULL);
1893 }
1894
1895 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1896 {
1897 for ( ; list; list = list->next)
1898 if (!strcmp(list->name, name))
1899 return (struct ref *)list;
1900 return NULL;
1901 }
1902
1903 /*
1904 * generate a format suitable for scanf from a ref_rev_parse_rules
1905 * rule, that is replace the "%.*s" spec with a "%s" spec
1906 */
1907 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1908 {
1909 char *spec;
1910
1911 spec = strstr(rule, "%.*s");
1912 if (!spec || strstr(spec + 4, "%.*s"))
1913 die("invalid rule in ref_rev_parse_rules: %s", rule);
1914
1915 /* copy all until spec */
1916 strncpy(scanf_fmt, rule, spec - rule);
1917 scanf_fmt[spec - rule] = '\0';
1918 /* copy new spec */
1919 strcat(scanf_fmt, "%s");
1920 /* copy remaining rule */
1921 strcat(scanf_fmt, spec + 4);
1922
1923 return;
1924 }
1925
1926 char *shorten_unambiguous_ref(const char *ref, int strict)
1927 {
1928 int i;
1929 static char **scanf_fmts;
1930 static int nr_rules;
1931 char *short_name;
1932
1933 /* pre generate scanf formats from ref_rev_parse_rules[] */
1934 if (!nr_rules) {
1935 size_t total_len = 0;
1936
1937 /* the rule list is NULL terminated, count them first */
1938 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1939 /* no +1 because strlen("%s") < strlen("%.*s") */
1940 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1941
1942 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1943
1944 total_len = 0;
1945 for (i = 0; i < nr_rules; i++) {
1946 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1947 + total_len;
1948 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1949 total_len += strlen(ref_rev_parse_rules[i]);
1950 }
1951 }
1952
1953 /* bail out if there are no rules */
1954 if (!nr_rules)
1955 return xstrdup(ref);
1956
1957 /* buffer for scanf result, at most ref must fit */
1958 short_name = xstrdup(ref);
1959
1960 /* skip first rule, it will always match */
1961 for (i = nr_rules - 1; i > 0 ; --i) {
1962 int j;
1963 int rules_to_fail = i;
1964 int short_name_len;
1965
1966 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1967 continue;
1968
1969 short_name_len = strlen(short_name);
1970
1971 /*
1972 * in strict mode, all (except the matched one) rules
1973 * must fail to resolve to a valid non-ambiguous ref
1974 */
1975 if (strict)
1976 rules_to_fail = nr_rules;
1977
1978 /*
1979 * check if the short name resolves to a valid ref,
1980 * but use only rules prior to the matched one
1981 */
1982 for (j = 0; j < rules_to_fail; j++) {
1983 const char *rule = ref_rev_parse_rules[j];
1984 unsigned char short_objectname[20];
1985 char refname[PATH_MAX];
1986
1987 /* skip matched rule */
1988 if (i == j)
1989 continue;
1990
1991 /*
1992 * the short name is ambiguous, if it resolves
1993 * (with this previous rule) to a valid ref
1994 * read_ref() returns 0 on success
1995 */
1996 mksnpath(refname, sizeof(refname),
1997 rule, short_name_len, short_name);
1998 if (!read_ref(refname, short_objectname))
1999 break;
2000 }
2001
2002 /*
2003 * short name is non-ambiguous if all previous rules
2004 * haven't resolved to a valid ref
2005 */
2006 if (j == rules_to_fail)
2007 return short_name;
2008 }
2009
2010 free(short_name);
2011 return xstrdup(ref);
2012 }