struct ref_entry: document name member
[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 /* The full name of the reference (e.g., "refs/heads/master"): */
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, int check_name, 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_name &&
64 check_refname_format(name, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
65 die("Reference has invalid format: '%s'", name);
66 memcpy(entry->name, name, len);
67 entry->flag = flag;
68 if (new_entry)
69 *new_entry = entry;
70 ALLOC_GROW(refs->refs, refs->nr + 1, refs->alloc);
71 refs->refs[refs->nr++] = entry;
72 }
73
74 static int ref_entry_cmp(const void *a, const void *b)
75 {
76 struct ref_entry *one = *(struct ref_entry **)a;
77 struct ref_entry *two = *(struct ref_entry **)b;
78 return strcmp(one->name, two->name);
79 }
80
81 static void sort_ref_array(struct ref_array *array)
82 {
83 int i = 0, j = 1;
84
85 /* Nothing to sort unless there are at least two entries */
86 if (array->nr < 2)
87 return;
88
89 qsort(array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
90
91 /* Remove any duplicates from the ref_array */
92 for (; j < array->nr; j++) {
93 struct ref_entry *a = array->refs[i];
94 struct ref_entry *b = array->refs[j];
95 if (!strcmp(a->name, b->name)) {
96 if (hashcmp(a->sha1, b->sha1))
97 die("Duplicated ref, and SHA1s don't match: %s",
98 a->name);
99 warning("Duplicated ref: %s", a->name);
100 free(b);
101 continue;
102 }
103 i++;
104 array->refs[i] = array->refs[j];
105 }
106 array->nr = i + 1;
107 }
108
109 static struct ref_entry *search_ref_array(struct ref_array *array, const char *name)
110 {
111 struct ref_entry *e, **r;
112 int len;
113
114 if (name == NULL)
115 return NULL;
116
117 if (!array->nr)
118 return NULL;
119
120 len = strlen(name) + 1;
121 e = xmalloc(sizeof(struct ref_entry) + len);
122 memcpy(e->name, name, len);
123
124 r = bsearch(&e, array->refs, array->nr, sizeof(*array->refs), ref_entry_cmp);
125
126 free(e);
127
128 if (r == NULL)
129 return NULL;
130
131 return *r;
132 }
133
134 /*
135 * Future: need to be in "struct repository"
136 * when doing a full libification.
137 */
138 static struct ref_cache {
139 struct ref_cache *next;
140 char did_loose;
141 char did_packed;
142 struct ref_array loose;
143 struct ref_array packed;
144 /* The submodule name, or "" for the main repo. */
145 char name[FLEX_ARRAY];
146 } *ref_cache;
147
148 static struct ref_entry *current_ref;
149
150 static struct ref_array extra_refs;
151
152 static void free_ref_array(struct ref_array *array)
153 {
154 int i;
155 for (i = 0; i < array->nr; i++)
156 free(array->refs[i]);
157 free(array->refs);
158 array->nr = array->alloc = 0;
159 array->refs = NULL;
160 }
161
162 static void clear_packed_ref_cache(struct ref_cache *refs)
163 {
164 if (refs->did_packed)
165 free_ref_array(&refs->packed);
166 refs->did_packed = 0;
167 }
168
169 static void clear_loose_ref_cache(struct ref_cache *refs)
170 {
171 if (refs->did_loose)
172 free_ref_array(&refs->loose);
173 refs->did_loose = 0;
174 }
175
176 static struct ref_cache *create_ref_cache(const char *submodule)
177 {
178 int len;
179 struct ref_cache *refs;
180 if (!submodule)
181 submodule = "";
182 len = strlen(submodule) + 1;
183 refs = xcalloc(1, sizeof(struct ref_cache) + len);
184 memcpy(refs->name, submodule, len);
185 return refs;
186 }
187
188 /*
189 * Return a pointer to a ref_cache for the specified submodule. For
190 * the main repository, use submodule==NULL. The returned structure
191 * will be allocated and initialized but not necessarily populated; it
192 * should not be freed.
193 */
194 static struct ref_cache *get_ref_cache(const char *submodule)
195 {
196 struct ref_cache *refs = ref_cache;
197 if (!submodule)
198 submodule = "";
199 while (refs) {
200 if (!strcmp(submodule, refs->name))
201 return refs;
202 refs = refs->next;
203 }
204
205 refs = create_ref_cache(submodule);
206 refs->next = ref_cache;
207 ref_cache = refs;
208 return refs;
209 }
210
211 void invalidate_ref_cache(const char *submodule)
212 {
213 struct ref_cache *refs = get_ref_cache(submodule);
214 clear_packed_ref_cache(refs);
215 clear_loose_ref_cache(refs);
216 }
217
218 static void read_packed_refs(FILE *f, struct ref_array *array)
219 {
220 struct ref_entry *last = NULL;
221 char refline[PATH_MAX];
222 int flag = REF_ISPACKED;
223
224 while (fgets(refline, sizeof(refline), f)) {
225 unsigned char sha1[20];
226 const char *name;
227 static const char header[] = "# pack-refs with:";
228
229 if (!strncmp(refline, header, sizeof(header)-1)) {
230 const char *traits = refline + sizeof(header) - 1;
231 if (strstr(traits, " peeled "))
232 flag |= REF_KNOWS_PEELED;
233 /* perhaps other traits later as well */
234 continue;
235 }
236
237 name = parse_ref_line(refline, sha1);
238 if (name) {
239 add_ref(name, sha1, flag, 1, array, &last);
240 continue;
241 }
242 if (last &&
243 refline[0] == '^' &&
244 strlen(refline) == 42 &&
245 refline[41] == '\n' &&
246 !get_sha1_hex(refline + 1, sha1))
247 hashcpy(last->peeled, sha1);
248 }
249 sort_ref_array(array);
250 }
251
252 void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
253 {
254 add_ref(name, sha1, flag, 0, &extra_refs, NULL);
255 }
256
257 void clear_extra_refs(void)
258 {
259 free_ref_array(&extra_refs);
260 }
261
262 static struct ref_array *get_packed_refs(const char *submodule)
263 {
264 struct ref_cache *refs = get_ref_cache(submodule);
265
266 if (!refs->did_packed) {
267 const char *packed_refs_file;
268 FILE *f;
269
270 if (submodule)
271 packed_refs_file = git_path_submodule(submodule, "packed-refs");
272 else
273 packed_refs_file = git_path("packed-refs");
274 f = fopen(packed_refs_file, "r");
275 if (f) {
276 read_packed_refs(f, &refs->packed);
277 fclose(f);
278 }
279 refs->did_packed = 1;
280 }
281 return &refs->packed;
282 }
283
284 static void get_ref_dir(const char *submodule, const char *base,
285 struct ref_array *array)
286 {
287 DIR *dir;
288 const char *path;
289
290 if (submodule)
291 path = git_path_submodule(submodule, "%s", base);
292 else
293 path = git_path("%s", base);
294
295
296 dir = opendir(path);
297
298 if (dir) {
299 struct dirent *de;
300 int baselen = strlen(base);
301 char *ref = xmalloc(baselen + 257);
302
303 memcpy(ref, base, baselen);
304 if (baselen && base[baselen-1] != '/')
305 ref[baselen++] = '/';
306
307 while ((de = readdir(dir)) != NULL) {
308 unsigned char sha1[20];
309 struct stat st;
310 int flag;
311 int namelen;
312 const char *refdir;
313
314 if (de->d_name[0] == '.')
315 continue;
316 namelen = strlen(de->d_name);
317 if (namelen > 255)
318 continue;
319 if (has_extension(de->d_name, ".lock"))
320 continue;
321 memcpy(ref + baselen, de->d_name, namelen+1);
322 refdir = submodule
323 ? git_path_submodule(submodule, "%s", ref)
324 : git_path("%s", ref);
325 if (stat(refdir, &st) < 0)
326 continue;
327 if (S_ISDIR(st.st_mode)) {
328 get_ref_dir(submodule, ref, array);
329 continue;
330 }
331 if (submodule) {
332 hashclr(sha1);
333 flag = 0;
334 if (resolve_gitlink_ref(submodule, ref, sha1) < 0) {
335 hashclr(sha1);
336 flag |= REF_ISBROKEN;
337 }
338 } else if (read_ref_full(ref, sha1, 1, &flag)) {
339 hashclr(sha1);
340 flag |= REF_ISBROKEN;
341 }
342 add_ref(ref, sha1, flag, 1, array, NULL);
343 }
344 free(ref);
345 closedir(dir);
346 }
347 }
348
349 struct warn_if_dangling_data {
350 FILE *fp;
351 const char *refname;
352 const char *msg_fmt;
353 };
354
355 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
356 int flags, void *cb_data)
357 {
358 struct warn_if_dangling_data *d = cb_data;
359 const char *resolves_to;
360 unsigned char junk[20];
361
362 if (!(flags & REF_ISSYMREF))
363 return 0;
364
365 resolves_to = resolve_ref(refname, junk, 0, NULL);
366 if (!resolves_to || strcmp(resolves_to, d->refname))
367 return 0;
368
369 fprintf(d->fp, d->msg_fmt, refname);
370 return 0;
371 }
372
373 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
374 {
375 struct warn_if_dangling_data data;
376
377 data.fp = fp;
378 data.refname = refname;
379 data.msg_fmt = msg_fmt;
380 for_each_rawref(warn_if_dangling_symref, &data);
381 }
382
383 static struct ref_array *get_loose_refs(const char *submodule)
384 {
385 struct ref_cache *refs = get_ref_cache(submodule);
386
387 if (!refs->did_loose) {
388 get_ref_dir(submodule, "refs", &refs->loose);
389 sort_ref_array(&refs->loose);
390 refs->did_loose = 1;
391 }
392 return &refs->loose;
393 }
394
395 /* We allow "recursive" symbolic refs. Only within reason, though */
396 #define MAXDEPTH 5
397 #define MAXREFLEN (1024)
398
399 /*
400 * Called by resolve_gitlink_ref_recursive() after it failed to read
401 * from "name", which is "module/.git/<refname>". Find <refname> in
402 * the packed-refs file for the submodule.
403 */
404 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
405 {
406 int retval = -1;
407 struct ref_entry *ref;
408 struct ref_array *array;
409
410 /* being defensive: resolve_gitlink_ref() did this for us */
411 if (pathlen < 6 || memcmp(name + pathlen - 6, "/.git/", 6))
412 die("Oops");
413 name[pathlen - 6] = '\0'; /* make it path to the submodule */
414 array = get_packed_refs(name);
415 ref = search_ref_array(array, refname);
416 if (ref != NULL) {
417 memcpy(result, ref->sha1, 20);
418 retval = 0;
419 }
420 return retval;
421 }
422
423 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
424 {
425 int fd, len = strlen(refname);
426 char buffer[128], *p;
427
428 if (recursion > MAXDEPTH || len > MAXREFLEN)
429 return -1;
430 memcpy(name + pathlen, refname, len+1);
431 fd = open(name, O_RDONLY);
432 if (fd < 0)
433 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
434
435 len = read(fd, buffer, sizeof(buffer)-1);
436 close(fd);
437 if (len < 0)
438 return -1;
439 while (len && isspace(buffer[len-1]))
440 len--;
441 buffer[len] = 0;
442
443 /* Was it a detached head or an old-fashioned symlink? */
444 if (!get_sha1_hex(buffer, result))
445 return 0;
446
447 /* Symref? */
448 if (strncmp(buffer, "ref:", 4))
449 return -1;
450 p = buffer + 4;
451 while (isspace(*p))
452 p++;
453
454 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
455 }
456
457 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
458 {
459 int len = strlen(path), retval;
460 char *gitdir;
461 const char *tmp;
462
463 while (len && path[len-1] == '/')
464 len--;
465 if (!len)
466 return -1;
467 gitdir = xmalloc(len + MAXREFLEN + 8);
468 memcpy(gitdir, path, len);
469 memcpy(gitdir + len, "/.git", 6);
470 len += 5;
471
472 tmp = read_gitfile(gitdir);
473 if (tmp) {
474 free(gitdir);
475 len = strlen(tmp);
476 gitdir = xmalloc(len + MAXREFLEN + 3);
477 memcpy(gitdir, tmp, len);
478 }
479 gitdir[len] = '/';
480 gitdir[++len] = '\0';
481 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
482 free(gitdir);
483 return retval;
484 }
485
486 /*
487 * Try to read ref from the packed references. On success, set sha1
488 * and return 0; otherwise, return -1.
489 */
490 static int get_packed_ref(const char *ref, unsigned char *sha1)
491 {
492 struct ref_array *packed = get_packed_refs(NULL);
493 struct ref_entry *entry = search_ref_array(packed, ref);
494 if (entry) {
495 hashcpy(sha1, entry->sha1);
496 return 0;
497 }
498 return -1;
499 }
500
501 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
502 {
503 int depth = MAXDEPTH;
504 ssize_t len;
505 char buffer[256];
506 static char ref_buffer[256];
507
508 if (flag)
509 *flag = 0;
510
511 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
512 return NULL;
513
514 for (;;) {
515 char path[PATH_MAX];
516 struct stat st;
517 char *buf;
518 int fd;
519
520 if (--depth < 0)
521 return NULL;
522
523 git_snpath(path, sizeof(path), "%s", ref);
524
525 if (lstat(path, &st) < 0) {
526 if (errno != ENOENT)
527 return NULL;
528 /*
529 * The loose reference file does not exist;
530 * check for a packed reference.
531 */
532 if (!get_packed_ref(ref, sha1)) {
533 if (flag)
534 *flag |= REF_ISPACKED;
535 return ref;
536 }
537 /* The reference is not a packed reference, either. */
538 if (reading) {
539 return NULL;
540 } else {
541 hashclr(sha1);
542 return ref;
543 }
544 }
545
546 /* Follow "normalized" - ie "refs/.." symlinks by hand */
547 if (S_ISLNK(st.st_mode)) {
548 len = readlink(path, buffer, sizeof(buffer)-1);
549 if (len < 0)
550 return NULL;
551 buffer[len] = 0;
552 if (!prefixcmp(buffer, "refs/") &&
553 !check_refname_format(buffer, 0)) {
554 strcpy(ref_buffer, buffer);
555 ref = ref_buffer;
556 if (flag)
557 *flag |= REF_ISSYMREF;
558 continue;
559 }
560 }
561
562 /* Is it a directory? */
563 if (S_ISDIR(st.st_mode)) {
564 errno = EISDIR;
565 return NULL;
566 }
567
568 /*
569 * Anything else, just open it and try to use it as
570 * a ref
571 */
572 fd = open(path, O_RDONLY);
573 if (fd < 0)
574 return NULL;
575 len = read_in_full(fd, buffer, sizeof(buffer)-1);
576 close(fd);
577 if (len < 0)
578 return NULL;
579 while (len && isspace(buffer[len-1]))
580 len--;
581 buffer[len] = '\0';
582
583 /*
584 * Is it a symbolic ref?
585 */
586 if (prefixcmp(buffer, "ref:"))
587 break;
588 if (flag)
589 *flag |= REF_ISSYMREF;
590 buf = buffer + 4;
591 while (isspace(*buf))
592 buf++;
593 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
594 if (flag)
595 *flag |= REF_ISBROKEN;
596 return NULL;
597 }
598 ref = strcpy(ref_buffer, buf);
599 }
600 /* Please note that FETCH_HEAD has a second line containing other data. */
601 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
602 if (flag)
603 *flag |= REF_ISBROKEN;
604 return NULL;
605 }
606 return ref;
607 }
608
609 /* The argument to filter_refs */
610 struct ref_filter {
611 const char *pattern;
612 each_ref_fn *fn;
613 void *cb_data;
614 };
615
616 int read_ref_full(const char *ref, unsigned char *sha1, int reading, int *flags)
617 {
618 if (resolve_ref(ref, sha1, reading, flags))
619 return 0;
620 return -1;
621 }
622
623 int read_ref(const char *ref, unsigned char *sha1)
624 {
625 return read_ref_full(ref, sha1, 1, NULL);
626 }
627
628 #define DO_FOR_EACH_INCLUDE_BROKEN 01
629 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
630 int flags, void *cb_data, struct ref_entry *entry)
631 {
632 if (prefixcmp(entry->name, base))
633 return 0;
634
635 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
636 if (entry->flag & REF_ISBROKEN)
637 return 0; /* ignore broken refs e.g. dangling symref */
638 if (!has_sha1_file(entry->sha1)) {
639 error("%s does not point to a valid object!", entry->name);
640 return 0;
641 }
642 }
643 current_ref = entry;
644 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
645 }
646
647 static int filter_refs(const char *ref, const unsigned char *sha, int flags,
648 void *data)
649 {
650 struct ref_filter *filter = (struct ref_filter *)data;
651 if (fnmatch(filter->pattern, ref, 0))
652 return 0;
653 return filter->fn(ref, sha, flags, filter->cb_data);
654 }
655
656 int peel_ref(const char *ref, unsigned char *sha1)
657 {
658 int flag;
659 unsigned char base[20];
660 struct object *o;
661
662 if (current_ref && (current_ref->name == ref
663 || !strcmp(current_ref->name, ref))) {
664 if (current_ref->flag & REF_KNOWS_PEELED) {
665 hashcpy(sha1, current_ref->peeled);
666 return 0;
667 }
668 hashcpy(base, current_ref->sha1);
669 goto fallback;
670 }
671
672 if (read_ref_full(ref, base, 1, &flag))
673 return -1;
674
675 if ((flag & REF_ISPACKED)) {
676 struct ref_array *array = get_packed_refs(NULL);
677 struct ref_entry *r = search_ref_array(array, ref);
678
679 if (r != NULL && r->flag & REF_KNOWS_PEELED) {
680 hashcpy(sha1, r->peeled);
681 return 0;
682 }
683 }
684
685 fallback:
686 o = parse_object(base);
687 if (o && o->type == OBJ_TAG) {
688 o = deref_tag(o, ref, 0);
689 if (o) {
690 hashcpy(sha1, o->sha1);
691 return 0;
692 }
693 }
694 return -1;
695 }
696
697 static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
698 int trim, int flags, void *cb_data)
699 {
700 int retval = 0, i, p = 0, l = 0;
701 struct ref_array *packed = get_packed_refs(submodule);
702 struct ref_array *loose = get_loose_refs(submodule);
703
704 struct ref_array *extra = &extra_refs;
705
706 for (i = 0; i < extra->nr; i++)
707 retval = do_one_ref(base, fn, trim, flags, cb_data, extra->refs[i]);
708
709 while (p < packed->nr && l < loose->nr) {
710 struct ref_entry *entry;
711 int cmp = strcmp(packed->refs[p]->name, loose->refs[l]->name);
712 if (!cmp) {
713 p++;
714 continue;
715 }
716 if (cmp > 0) {
717 entry = loose->refs[l++];
718 } else {
719 entry = packed->refs[p++];
720 }
721 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
722 if (retval)
723 goto end_each;
724 }
725
726 if (l < loose->nr) {
727 p = l;
728 packed = loose;
729 }
730
731 for (; p < packed->nr; p++) {
732 retval = do_one_ref(base, fn, trim, flags, cb_data, packed->refs[p]);
733 if (retval)
734 goto end_each;
735 }
736
737 end_each:
738 current_ref = NULL;
739 return retval;
740 }
741
742
743 static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
744 {
745 unsigned char sha1[20];
746 int flag;
747
748 if (submodule) {
749 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
750 return fn("HEAD", sha1, 0, cb_data);
751
752 return 0;
753 }
754
755 if (!read_ref_full("HEAD", sha1, 1, &flag))
756 return fn("HEAD", sha1, flag, cb_data);
757
758 return 0;
759 }
760
761 int head_ref(each_ref_fn fn, void *cb_data)
762 {
763 return do_head_ref(NULL, fn, cb_data);
764 }
765
766 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
767 {
768 return do_head_ref(submodule, fn, cb_data);
769 }
770
771 int for_each_ref(each_ref_fn fn, void *cb_data)
772 {
773 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
774 }
775
776 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
777 {
778 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
779 }
780
781 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
782 {
783 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
784 }
785
786 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
787 each_ref_fn fn, void *cb_data)
788 {
789 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
790 }
791
792 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
793 {
794 return for_each_ref_in("refs/tags/", fn, cb_data);
795 }
796
797 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
798 {
799 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
800 }
801
802 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
803 {
804 return for_each_ref_in("refs/heads/", fn, cb_data);
805 }
806
807 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
808 {
809 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
810 }
811
812 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
813 {
814 return for_each_ref_in("refs/remotes/", fn, cb_data);
815 }
816
817 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
818 {
819 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
820 }
821
822 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
823 {
824 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
825 }
826
827 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
828 {
829 struct strbuf buf = STRBUF_INIT;
830 int ret = 0;
831 unsigned char sha1[20];
832 int flag;
833
834 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
835 if (!read_ref_full(buf.buf, sha1, 1, &flag))
836 ret = fn(buf.buf, sha1, flag, cb_data);
837 strbuf_release(&buf);
838
839 return ret;
840 }
841
842 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
843 {
844 struct strbuf buf = STRBUF_INIT;
845 int ret;
846 strbuf_addf(&buf, "%srefs/", get_git_namespace());
847 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
848 strbuf_release(&buf);
849 return ret;
850 }
851
852 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
853 const char *prefix, void *cb_data)
854 {
855 struct strbuf real_pattern = STRBUF_INIT;
856 struct ref_filter filter;
857 int ret;
858
859 if (!prefix && prefixcmp(pattern, "refs/"))
860 strbuf_addstr(&real_pattern, "refs/");
861 else if (prefix)
862 strbuf_addstr(&real_pattern, prefix);
863 strbuf_addstr(&real_pattern, pattern);
864
865 if (!has_glob_specials(pattern)) {
866 /* Append implied '/' '*' if not present. */
867 if (real_pattern.buf[real_pattern.len - 1] != '/')
868 strbuf_addch(&real_pattern, '/');
869 /* No need to check for '*', there is none. */
870 strbuf_addch(&real_pattern, '*');
871 }
872
873 filter.pattern = real_pattern.buf;
874 filter.fn = fn;
875 filter.cb_data = cb_data;
876 ret = for_each_ref(filter_refs, &filter);
877
878 strbuf_release(&real_pattern);
879 return ret;
880 }
881
882 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
883 {
884 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
885 }
886
887 int for_each_rawref(each_ref_fn fn, void *cb_data)
888 {
889 return do_for_each_ref(NULL, "", fn, 0,
890 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
891 }
892
893 /*
894 * Make sure "ref" is something reasonable to have under ".git/refs/";
895 * We do not like it if:
896 *
897 * - any path component of it begins with ".", or
898 * - it has double dots "..", or
899 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
900 * - it ends with a "/".
901 * - it ends with ".lock"
902 * - it contains a "\" (backslash)
903 */
904
905 /* Return true iff ch is not allowed in reference names. */
906 static inline int bad_ref_char(int ch)
907 {
908 if (((unsigned) ch) <= ' ' || ch == 0x7f ||
909 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
910 return 1;
911 /* 2.13 Pattern Matching Notation */
912 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
913 return 1;
914 return 0;
915 }
916
917 /*
918 * Try to read one refname component from the front of ref. Return
919 * the length of the component found, or -1 if the component is not
920 * legal.
921 */
922 static int check_refname_component(const char *ref, int flags)
923 {
924 const char *cp;
925 char last = '\0';
926
927 for (cp = ref; ; cp++) {
928 char ch = *cp;
929 if (ch == '\0' || ch == '/')
930 break;
931 if (bad_ref_char(ch))
932 return -1; /* Illegal character in refname. */
933 if (last == '.' && ch == '.')
934 return -1; /* Refname contains "..". */
935 if (last == '@' && ch == '{')
936 return -1; /* Refname contains "@{". */
937 last = ch;
938 }
939 if (cp == ref)
940 return -1; /* Component has zero length. */
941 if (ref[0] == '.') {
942 if (!(flags & REFNAME_DOT_COMPONENT))
943 return -1; /* Component starts with '.'. */
944 /*
945 * Even if leading dots are allowed, don't allow "."
946 * as a component (".." is prevented by a rule above).
947 */
948 if (ref[1] == '\0')
949 return -1; /* Component equals ".". */
950 }
951 if (cp - ref >= 5 && !memcmp(cp - 5, ".lock", 5))
952 return -1; /* Refname ends with ".lock". */
953 return cp - ref;
954 }
955
956 int check_refname_format(const char *ref, int flags)
957 {
958 int component_len, component_count = 0;
959
960 while (1) {
961 /* We are at the start of a path component. */
962 component_len = check_refname_component(ref, flags);
963 if (component_len < 0) {
964 if ((flags & REFNAME_REFSPEC_PATTERN) &&
965 ref[0] == '*' &&
966 (ref[1] == '\0' || ref[1] == '/')) {
967 /* Accept one wildcard as a full refname component. */
968 flags &= ~REFNAME_REFSPEC_PATTERN;
969 component_len = 1;
970 } else {
971 return -1;
972 }
973 }
974 component_count++;
975 if (ref[component_len] == '\0')
976 break;
977 /* Skip to next component. */
978 ref += component_len + 1;
979 }
980
981 if (ref[component_len - 1] == '.')
982 return -1; /* Refname ends with '.'. */
983 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
984 return -1; /* Refname has only one component. */
985 return 0;
986 }
987
988 const char *prettify_refname(const char *name)
989 {
990 return name + (
991 !prefixcmp(name, "refs/heads/") ? 11 :
992 !prefixcmp(name, "refs/tags/") ? 10 :
993 !prefixcmp(name, "refs/remotes/") ? 13 :
994 0);
995 }
996
997 const char *ref_rev_parse_rules[] = {
998 "%.*s",
999 "refs/%.*s",
1000 "refs/tags/%.*s",
1001 "refs/heads/%.*s",
1002 "refs/remotes/%.*s",
1003 "refs/remotes/%.*s/HEAD",
1004 NULL
1005 };
1006
1007 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
1008 {
1009 const char **p;
1010 const int abbrev_name_len = strlen(abbrev_name);
1011
1012 for (p = rules; *p; p++) {
1013 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
1014 return 1;
1015 }
1016 }
1017
1018 return 0;
1019 }
1020
1021 static struct ref_lock *verify_lock(struct ref_lock *lock,
1022 const unsigned char *old_sha1, int mustexist)
1023 {
1024 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
1025 error("Can't verify ref %s", lock->ref_name);
1026 unlock_ref(lock);
1027 return NULL;
1028 }
1029 if (hashcmp(lock->old_sha1, old_sha1)) {
1030 error("Ref %s is at %s but expected %s", lock->ref_name,
1031 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
1032 unlock_ref(lock);
1033 return NULL;
1034 }
1035 return lock;
1036 }
1037
1038 static int remove_empty_directories(const char *file)
1039 {
1040 /* we want to create a file but there is a directory there;
1041 * if that is an empty directory (or a directory that contains
1042 * only empty directories), remove them.
1043 */
1044 struct strbuf path;
1045 int result;
1046
1047 strbuf_init(&path, 20);
1048 strbuf_addstr(&path, file);
1049
1050 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
1051
1052 strbuf_release(&path);
1053
1054 return result;
1055 }
1056
1057 static int is_refname_available(const char *ref, const char *oldref,
1058 struct ref_array *array, int quiet)
1059 {
1060 int i, namlen = strlen(ref); /* e.g. 'foo/bar' */
1061 for (i = 0; i < array->nr; i++ ) {
1062 struct ref_entry *entry = array->refs[i];
1063 /* entry->name could be 'foo' or 'foo/bar/baz' */
1064 if (!oldref || strcmp(oldref, entry->name)) {
1065 int len = strlen(entry->name);
1066 int cmplen = (namlen < len) ? namlen : len;
1067 const char *lead = (namlen < len) ? entry->name : ref;
1068 if (!strncmp(ref, entry->name, cmplen) &&
1069 lead[cmplen] == '/') {
1070 if (!quiet)
1071 error("'%s' exists; cannot create '%s'",
1072 entry->name, ref);
1073 return 0;
1074 }
1075 }
1076 }
1077 return 1;
1078 }
1079
1080 /*
1081 * *string and *len will only be substituted, and *string returned (for
1082 * later free()ing) if the string passed in is a magic short-hand form
1083 * to name a branch.
1084 */
1085 static char *substitute_branch_name(const char **string, int *len)
1086 {
1087 struct strbuf buf = STRBUF_INIT;
1088 int ret = interpret_branch_name(*string, &buf);
1089
1090 if (ret == *len) {
1091 size_t size;
1092 *string = strbuf_detach(&buf, &size);
1093 *len = size;
1094 return (char *)*string;
1095 }
1096
1097 return NULL;
1098 }
1099
1100 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
1101 {
1102 char *last_branch = substitute_branch_name(&str, &len);
1103 const char **p, *r;
1104 int refs_found = 0;
1105
1106 *ref = NULL;
1107 for (p = ref_rev_parse_rules; *p; p++) {
1108 char fullref[PATH_MAX];
1109 unsigned char sha1_from_ref[20];
1110 unsigned char *this_result;
1111 int flag;
1112
1113 this_result = refs_found ? sha1_from_ref : sha1;
1114 mksnpath(fullref, sizeof(fullref), *p, len, str);
1115 r = resolve_ref(fullref, this_result, 1, &flag);
1116 if (r) {
1117 if (!refs_found++)
1118 *ref = xstrdup(r);
1119 if (!warn_ambiguous_refs)
1120 break;
1121 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
1122 warning("ignoring dangling symref %s.", fullref);
1123 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
1124 warning("ignoring broken ref %s.", fullref);
1125 }
1126 }
1127 free(last_branch);
1128 return refs_found;
1129 }
1130
1131 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
1132 {
1133 char *last_branch = substitute_branch_name(&str, &len);
1134 const char **p;
1135 int logs_found = 0;
1136
1137 *log = NULL;
1138 for (p = ref_rev_parse_rules; *p; p++) {
1139 struct stat st;
1140 unsigned char hash[20];
1141 char path[PATH_MAX];
1142 const char *ref, *it;
1143
1144 mksnpath(path, sizeof(path), *p, len, str);
1145 ref = resolve_ref(path, hash, 1, NULL);
1146 if (!ref)
1147 continue;
1148 if (!stat(git_path("logs/%s", path), &st) &&
1149 S_ISREG(st.st_mode))
1150 it = path;
1151 else if (strcmp(ref, path) &&
1152 !stat(git_path("logs/%s", ref), &st) &&
1153 S_ISREG(st.st_mode))
1154 it = ref;
1155 else
1156 continue;
1157 if (!logs_found++) {
1158 *log = xstrdup(it);
1159 hashcpy(sha1, hash);
1160 }
1161 if (!warn_ambiguous_refs)
1162 break;
1163 }
1164 free(last_branch);
1165 return logs_found;
1166 }
1167
1168 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
1169 {
1170 char *ref_file;
1171 const char *orig_ref = ref;
1172 struct ref_lock *lock;
1173 int last_errno = 0;
1174 int type, lflags;
1175 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
1176 int missing = 0;
1177
1178 lock = xcalloc(1, sizeof(struct ref_lock));
1179 lock->lock_fd = -1;
1180
1181 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
1182 if (!ref && errno == EISDIR) {
1183 /* we are trying to lock foo but we used to
1184 * have foo/bar which now does not exist;
1185 * it is normal for the empty directory 'foo'
1186 * to remain.
1187 */
1188 ref_file = git_path("%s", orig_ref);
1189 if (remove_empty_directories(ref_file)) {
1190 last_errno = errno;
1191 error("there are still refs under '%s'", orig_ref);
1192 goto error_return;
1193 }
1194 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
1195 }
1196 if (type_p)
1197 *type_p = type;
1198 if (!ref) {
1199 last_errno = errno;
1200 error("unable to resolve reference %s: %s",
1201 orig_ref, strerror(errno));
1202 goto error_return;
1203 }
1204 missing = is_null_sha1(lock->old_sha1);
1205 /* When the ref did not exist and we are creating it,
1206 * make sure there is no existing ref that is packed
1207 * whose name begins with our refname, nor a ref whose
1208 * name is a proper prefix of our refname.
1209 */
1210 if (missing &&
1211 !is_refname_available(ref, NULL, get_packed_refs(NULL), 0)) {
1212 last_errno = ENOTDIR;
1213 goto error_return;
1214 }
1215
1216 lock->lk = xcalloc(1, sizeof(struct lock_file));
1217
1218 lflags = LOCK_DIE_ON_ERROR;
1219 if (flags & REF_NODEREF) {
1220 ref = orig_ref;
1221 lflags |= LOCK_NODEREF;
1222 }
1223 lock->ref_name = xstrdup(ref);
1224 lock->orig_ref_name = xstrdup(orig_ref);
1225 ref_file = git_path("%s", ref);
1226 if (missing)
1227 lock->force_write = 1;
1228 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
1229 lock->force_write = 1;
1230
1231 if (safe_create_leading_directories(ref_file)) {
1232 last_errno = errno;
1233 error("unable to create directory for %s", ref_file);
1234 goto error_return;
1235 }
1236
1237 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
1238 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
1239
1240 error_return:
1241 unlock_ref(lock);
1242 errno = last_errno;
1243 return NULL;
1244 }
1245
1246 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
1247 {
1248 char refpath[PATH_MAX];
1249 if (check_refname_format(ref, 0))
1250 return NULL;
1251 strcpy(refpath, mkpath("refs/%s", ref));
1252 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
1253 }
1254
1255 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
1256 {
1257 if (check_refname_format(ref, REFNAME_ALLOW_ONELEVEL))
1258 return NULL;
1259 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
1260 }
1261
1262 static struct lock_file packlock;
1263
1264 static int repack_without_ref(const char *refname)
1265 {
1266 struct ref_array *packed;
1267 struct ref_entry *ref;
1268 int fd, i;
1269
1270 packed = get_packed_refs(NULL);
1271 ref = search_ref_array(packed, refname);
1272 if (ref == NULL)
1273 return 0;
1274 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
1275 if (fd < 0) {
1276 unable_to_lock_error(git_path("packed-refs"), errno);
1277 return error("cannot delete '%s' from packed refs", refname);
1278 }
1279
1280 for (i = 0; i < packed->nr; i++) {
1281 char line[PATH_MAX + 100];
1282 int len;
1283
1284 ref = packed->refs[i];
1285
1286 if (!strcmp(refname, ref->name))
1287 continue;
1288 len = snprintf(line, sizeof(line), "%s %s\n",
1289 sha1_to_hex(ref->sha1), ref->name);
1290 /* this should not happen but just being defensive */
1291 if (len > sizeof(line))
1292 die("too long a refname '%s'", ref->name);
1293 write_or_die(fd, line, len);
1294 }
1295 return commit_lock_file(&packlock);
1296 }
1297
1298 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
1299 {
1300 struct ref_lock *lock;
1301 int err, i = 0, ret = 0, flag = 0;
1302
1303 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
1304 if (!lock)
1305 return 1;
1306 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1307 /* loose */
1308 const char *path;
1309
1310 if (!(delopt & REF_NODEREF)) {
1311 i = strlen(lock->lk->filename) - 5; /* .lock */
1312 lock->lk->filename[i] = 0;
1313 path = lock->lk->filename;
1314 } else {
1315 path = git_path("%s", refname);
1316 }
1317 err = unlink_or_warn(path);
1318 if (err && errno != ENOENT)
1319 ret = 1;
1320
1321 if (!(delopt & REF_NODEREF))
1322 lock->lk->filename[i] = '.';
1323 }
1324 /* removing the loose one could have resurrected an earlier
1325 * packed one. Also, if it was not loose we need to repack
1326 * without it.
1327 */
1328 ret |= repack_without_ref(refname);
1329
1330 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1331 invalidate_ref_cache(NULL);
1332 unlock_ref(lock);
1333 return ret;
1334 }
1335
1336 /*
1337 * People using contrib's git-new-workdir have .git/logs/refs ->
1338 * /some/other/path/.git/logs/refs, and that may live on another device.
1339 *
1340 * IOW, to avoid cross device rename errors, the temporary renamed log must
1341 * live into logs/refs.
1342 */
1343 #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"
1344
1345 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1346 {
1347 unsigned char sha1[20], orig_sha1[20];
1348 int flag = 0, logmoved = 0;
1349 struct ref_lock *lock;
1350 struct stat loginfo;
1351 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1352 const char *symref = NULL;
1353
1354 if (log && S_ISLNK(loginfo.st_mode))
1355 return error("reflog for %s is a symlink", oldref);
1356
1357 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1358 if (flag & REF_ISSYMREF)
1359 return error("refname %s is a symbolic ref, renaming it is not supported",
1360 oldref);
1361 if (!symref)
1362 return error("refname %s not found", oldref);
1363
1364 if (!is_refname_available(newref, oldref, get_packed_refs(NULL), 0))
1365 return 1;
1366
1367 if (!is_refname_available(newref, oldref, get_loose_refs(NULL), 0))
1368 return 1;
1369
1370 if (log && rename(git_path("logs/%s", oldref), git_path(TMP_RENAMED_LOG)))
1371 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
1372 oldref, strerror(errno));
1373
1374 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1375 error("unable to delete old %s", oldref);
1376 goto rollback;
1377 }
1378
1379 if (!read_ref_full(newref, sha1, 1, &flag) &&
1380 delete_ref(newref, sha1, REF_NODEREF)) {
1381 if (errno==EISDIR) {
1382 if (remove_empty_directories(git_path("%s", newref))) {
1383 error("Directory not empty: %s", newref);
1384 goto rollback;
1385 }
1386 } else {
1387 error("unable to delete existing %s", newref);
1388 goto rollback;
1389 }
1390 }
1391
1392 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1393 error("unable to create directory for %s", newref);
1394 goto rollback;
1395 }
1396
1397 retry:
1398 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newref))) {
1399 if (errno==EISDIR || errno==ENOTDIR) {
1400 /*
1401 * rename(a, b) when b is an existing
1402 * directory ought to result in ISDIR, but
1403 * Solaris 5.8 gives ENOTDIR. Sheesh.
1404 */
1405 if (remove_empty_directories(git_path("logs/%s", newref))) {
1406 error("Directory not empty: logs/%s", newref);
1407 goto rollback;
1408 }
1409 goto retry;
1410 } else {
1411 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
1412 newref, strerror(errno));
1413 goto rollback;
1414 }
1415 }
1416 logmoved = log;
1417
1418 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1419 if (!lock) {
1420 error("unable to lock %s for update", newref);
1421 goto rollback;
1422 }
1423 lock->force_write = 1;
1424 hashcpy(lock->old_sha1, orig_sha1);
1425 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1426 error("unable to write current sha1 into %s", newref);
1427 goto rollback;
1428 }
1429
1430 return 0;
1431
1432 rollback:
1433 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1434 if (!lock) {
1435 error("unable to lock %s for rollback", oldref);
1436 goto rollbacklog;
1437 }
1438
1439 lock->force_write = 1;
1440 flag = log_all_ref_updates;
1441 log_all_ref_updates = 0;
1442 if (write_ref_sha1(lock, orig_sha1, NULL))
1443 error("unable to write current sha1 into %s", oldref);
1444 log_all_ref_updates = flag;
1445
1446 rollbacklog:
1447 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1448 error("unable to restore logfile %s from %s: %s",
1449 oldref, newref, strerror(errno));
1450 if (!logmoved && log &&
1451 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldref)))
1452 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
1453 oldref, strerror(errno));
1454
1455 return 1;
1456 }
1457
1458 int close_ref(struct ref_lock *lock)
1459 {
1460 if (close_lock_file(lock->lk))
1461 return -1;
1462 lock->lock_fd = -1;
1463 return 0;
1464 }
1465
1466 int commit_ref(struct ref_lock *lock)
1467 {
1468 if (commit_lock_file(lock->lk))
1469 return -1;
1470 lock->lock_fd = -1;
1471 return 0;
1472 }
1473
1474 void unlock_ref(struct ref_lock *lock)
1475 {
1476 /* Do not free lock->lk -- atexit() still looks at them */
1477 if (lock->lk)
1478 rollback_lock_file(lock->lk);
1479 free(lock->ref_name);
1480 free(lock->orig_ref_name);
1481 free(lock);
1482 }
1483
1484 /*
1485 * copy the reflog message msg to buf, which has been allocated sufficiently
1486 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1487 * because reflog file is one line per entry.
1488 */
1489 static int copy_msg(char *buf, const char *msg)
1490 {
1491 char *cp = buf;
1492 char c;
1493 int wasspace = 1;
1494
1495 *cp++ = '\t';
1496 while ((c = *msg++)) {
1497 if (wasspace && isspace(c))
1498 continue;
1499 wasspace = isspace(c);
1500 if (wasspace)
1501 c = ' ';
1502 *cp++ = c;
1503 }
1504 while (buf < cp && isspace(cp[-1]))
1505 cp--;
1506 *cp++ = '\n';
1507 return cp - buf;
1508 }
1509
1510 int log_ref_setup(const char *ref_name, char *logfile, int bufsize)
1511 {
1512 int logfd, oflags = O_APPEND | O_WRONLY;
1513
1514 git_snpath(logfile, bufsize, "logs/%s", ref_name);
1515 if (log_all_ref_updates &&
1516 (!prefixcmp(ref_name, "refs/heads/") ||
1517 !prefixcmp(ref_name, "refs/remotes/") ||
1518 !prefixcmp(ref_name, "refs/notes/") ||
1519 !strcmp(ref_name, "HEAD"))) {
1520 if (safe_create_leading_directories(logfile) < 0)
1521 return error("unable to create directory for %s",
1522 logfile);
1523 oflags |= O_CREAT;
1524 }
1525
1526 logfd = open(logfile, oflags, 0666);
1527 if (logfd < 0) {
1528 if (!(oflags & O_CREAT) && errno == ENOENT)
1529 return 0;
1530
1531 if ((oflags & O_CREAT) && errno == EISDIR) {
1532 if (remove_empty_directories(logfile)) {
1533 return error("There are still logs under '%s'",
1534 logfile);
1535 }
1536 logfd = open(logfile, oflags, 0666);
1537 }
1538
1539 if (logfd < 0)
1540 return error("Unable to append to %s: %s",
1541 logfile, strerror(errno));
1542 }
1543
1544 adjust_shared_perm(logfile);
1545 close(logfd);
1546 return 0;
1547 }
1548
1549 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1550 const unsigned char *new_sha1, const char *msg)
1551 {
1552 int logfd, result, written, oflags = O_APPEND | O_WRONLY;
1553 unsigned maxlen, len;
1554 int msglen;
1555 char log_file[PATH_MAX];
1556 char *logrec;
1557 const char *committer;
1558
1559 if (log_all_ref_updates < 0)
1560 log_all_ref_updates = !is_bare_repository();
1561
1562 result = log_ref_setup(ref_name, log_file, sizeof(log_file));
1563 if (result)
1564 return result;
1565
1566 logfd = open(log_file, oflags);
1567 if (logfd < 0)
1568 return 0;
1569 msglen = msg ? strlen(msg) : 0;
1570 committer = git_committer_info(0);
1571 maxlen = strlen(committer) + msglen + 100;
1572 logrec = xmalloc(maxlen);
1573 len = sprintf(logrec, "%s %s %s\n",
1574 sha1_to_hex(old_sha1),
1575 sha1_to_hex(new_sha1),
1576 committer);
1577 if (msglen)
1578 len += copy_msg(logrec + len - 1, msg) - 1;
1579 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1580 free(logrec);
1581 if (close(logfd) != 0 || written != len)
1582 return error("Unable to append to %s", log_file);
1583 return 0;
1584 }
1585
1586 static int is_branch(const char *refname)
1587 {
1588 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1589 }
1590
1591 int write_ref_sha1(struct ref_lock *lock,
1592 const unsigned char *sha1, const char *logmsg)
1593 {
1594 static char term = '\n';
1595 struct object *o;
1596
1597 if (!lock)
1598 return -1;
1599 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1600 unlock_ref(lock);
1601 return 0;
1602 }
1603 o = parse_object(sha1);
1604 if (!o) {
1605 error("Trying to write ref %s with nonexistent object %s",
1606 lock->ref_name, sha1_to_hex(sha1));
1607 unlock_ref(lock);
1608 return -1;
1609 }
1610 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1611 error("Trying to write non-commit object %s to branch %s",
1612 sha1_to_hex(sha1), lock->ref_name);
1613 unlock_ref(lock);
1614 return -1;
1615 }
1616 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1617 write_in_full(lock->lock_fd, &term, 1) != 1
1618 || close_ref(lock) < 0) {
1619 error("Couldn't write %s", lock->lk->filename);
1620 unlock_ref(lock);
1621 return -1;
1622 }
1623 clear_loose_ref_cache(get_ref_cache(NULL));
1624 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1625 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1626 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1627 unlock_ref(lock);
1628 return -1;
1629 }
1630 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1631 /*
1632 * Special hack: If a branch is updated directly and HEAD
1633 * points to it (may happen on the remote side of a push
1634 * for example) then logically the HEAD reflog should be
1635 * updated too.
1636 * A generic solution implies reverse symref information,
1637 * but finding all symrefs pointing to the given branch
1638 * would be rather costly for this rare event (the direct
1639 * update of a branch) to be worth it. So let's cheat and
1640 * check with HEAD only which should cover 99% of all usage
1641 * scenarios (even 100% of the default ones).
1642 */
1643 unsigned char head_sha1[20];
1644 int head_flag;
1645 const char *head_ref;
1646 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1647 if (head_ref && (head_flag & REF_ISSYMREF) &&
1648 !strcmp(head_ref, lock->ref_name))
1649 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1650 }
1651 if (commit_ref(lock)) {
1652 error("Couldn't set %s", lock->ref_name);
1653 unlock_ref(lock);
1654 return -1;
1655 }
1656 unlock_ref(lock);
1657 return 0;
1658 }
1659
1660 int create_symref(const char *ref_target, const char *refs_heads_master,
1661 const char *logmsg)
1662 {
1663 const char *lockpath;
1664 char ref[1000];
1665 int fd, len, written;
1666 char *git_HEAD = git_pathdup("%s", ref_target);
1667 unsigned char old_sha1[20], new_sha1[20];
1668
1669 if (logmsg && read_ref(ref_target, old_sha1))
1670 hashclr(old_sha1);
1671
1672 if (safe_create_leading_directories(git_HEAD) < 0)
1673 return error("unable to create directory for %s", git_HEAD);
1674
1675 #ifndef NO_SYMLINK_HEAD
1676 if (prefer_symlink_refs) {
1677 unlink(git_HEAD);
1678 if (!symlink(refs_heads_master, git_HEAD))
1679 goto done;
1680 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1681 }
1682 #endif
1683
1684 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1685 if (sizeof(ref) <= len) {
1686 error("refname too long: %s", refs_heads_master);
1687 goto error_free_return;
1688 }
1689 lockpath = mkpath("%s.lock", git_HEAD);
1690 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1691 if (fd < 0) {
1692 error("Unable to open %s for writing", lockpath);
1693 goto error_free_return;
1694 }
1695 written = write_in_full(fd, ref, len);
1696 if (close(fd) != 0 || written != len) {
1697 error("Unable to write to %s", lockpath);
1698 goto error_unlink_return;
1699 }
1700 if (rename(lockpath, git_HEAD) < 0) {
1701 error("Unable to create %s", git_HEAD);
1702 goto error_unlink_return;
1703 }
1704 if (adjust_shared_perm(git_HEAD)) {
1705 error("Unable to fix permissions on %s", lockpath);
1706 error_unlink_return:
1707 unlink_or_warn(lockpath);
1708 error_free_return:
1709 free(git_HEAD);
1710 return -1;
1711 }
1712
1713 #ifndef NO_SYMLINK_HEAD
1714 done:
1715 #endif
1716 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1717 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1718
1719 free(git_HEAD);
1720 return 0;
1721 }
1722
1723 static char *ref_msg(const char *line, const char *endp)
1724 {
1725 const char *ep;
1726 line += 82;
1727 ep = memchr(line, '\n', endp - line);
1728 if (!ep)
1729 ep = endp;
1730 return xmemdupz(line, ep - line);
1731 }
1732
1733 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)
1734 {
1735 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1736 char *tz_c;
1737 int logfd, tz, reccnt = 0;
1738 struct stat st;
1739 unsigned long date;
1740 unsigned char logged_sha1[20];
1741 void *log_mapped;
1742 size_t mapsz;
1743
1744 logfile = git_path("logs/%s", ref);
1745 logfd = open(logfile, O_RDONLY, 0);
1746 if (logfd < 0)
1747 die_errno("Unable to read log '%s'", logfile);
1748 fstat(logfd, &st);
1749 if (!st.st_size)
1750 die("Log %s is empty.", logfile);
1751 mapsz = xsize_t(st.st_size);
1752 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1753 logdata = log_mapped;
1754 close(logfd);
1755
1756 lastrec = NULL;
1757 rec = logend = logdata + st.st_size;
1758 while (logdata < rec) {
1759 reccnt++;
1760 if (logdata < rec && *(rec-1) == '\n')
1761 rec--;
1762 lastgt = NULL;
1763 while (logdata < rec && *(rec-1) != '\n') {
1764 rec--;
1765 if (*rec == '>')
1766 lastgt = rec;
1767 }
1768 if (!lastgt)
1769 die("Log %s is corrupt.", logfile);
1770 date = strtoul(lastgt + 1, &tz_c, 10);
1771 if (date <= at_time || cnt == 0) {
1772 tz = strtoul(tz_c, NULL, 10);
1773 if (msg)
1774 *msg = ref_msg(rec, logend);
1775 if (cutoff_time)
1776 *cutoff_time = date;
1777 if (cutoff_tz)
1778 *cutoff_tz = tz;
1779 if (cutoff_cnt)
1780 *cutoff_cnt = reccnt - 1;
1781 if (lastrec) {
1782 if (get_sha1_hex(lastrec, logged_sha1))
1783 die("Log %s is corrupt.", logfile);
1784 if (get_sha1_hex(rec + 41, sha1))
1785 die("Log %s is corrupt.", logfile);
1786 if (hashcmp(logged_sha1, sha1)) {
1787 warning("Log %s has gap after %s.",
1788 logfile, show_date(date, tz, DATE_RFC2822));
1789 }
1790 }
1791 else if (date == at_time) {
1792 if (get_sha1_hex(rec + 41, sha1))
1793 die("Log %s is corrupt.", logfile);
1794 }
1795 else {
1796 if (get_sha1_hex(rec + 41, logged_sha1))
1797 die("Log %s is corrupt.", logfile);
1798 if (hashcmp(logged_sha1, sha1)) {
1799 warning("Log %s unexpectedly ended on %s.",
1800 logfile, show_date(date, tz, DATE_RFC2822));
1801 }
1802 }
1803 munmap(log_mapped, mapsz);
1804 return 0;
1805 }
1806 lastrec = rec;
1807 if (cnt > 0)
1808 cnt--;
1809 }
1810
1811 rec = logdata;
1812 while (rec < logend && *rec != '>' && *rec != '\n')
1813 rec++;
1814 if (rec == logend || *rec == '\n')
1815 die("Log %s is corrupt.", logfile);
1816 date = strtoul(rec + 1, &tz_c, 10);
1817 tz = strtoul(tz_c, NULL, 10);
1818 if (get_sha1_hex(logdata, sha1))
1819 die("Log %s is corrupt.", logfile);
1820 if (is_null_sha1(sha1)) {
1821 if (get_sha1_hex(logdata + 41, sha1))
1822 die("Log %s is corrupt.", logfile);
1823 }
1824 if (msg)
1825 *msg = ref_msg(logdata, logend);
1826 munmap(log_mapped, mapsz);
1827
1828 if (cutoff_time)
1829 *cutoff_time = date;
1830 if (cutoff_tz)
1831 *cutoff_tz = tz;
1832 if (cutoff_cnt)
1833 *cutoff_cnt = reccnt;
1834 return 1;
1835 }
1836
1837 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1838 {
1839 const char *logfile;
1840 FILE *logfp;
1841 struct strbuf sb = STRBUF_INIT;
1842 int ret = 0;
1843
1844 logfile = git_path("logs/%s", ref);
1845 logfp = fopen(logfile, "r");
1846 if (!logfp)
1847 return -1;
1848
1849 if (ofs) {
1850 struct stat statbuf;
1851 if (fstat(fileno(logfp), &statbuf) ||
1852 statbuf.st_size < ofs ||
1853 fseek(logfp, -ofs, SEEK_END) ||
1854 strbuf_getwholeline(&sb, logfp, '\n')) {
1855 fclose(logfp);
1856 strbuf_release(&sb);
1857 return -1;
1858 }
1859 }
1860
1861 while (!strbuf_getwholeline(&sb, logfp, '\n')) {
1862 unsigned char osha1[20], nsha1[20];
1863 char *email_end, *message;
1864 unsigned long timestamp;
1865 int tz;
1866
1867 /* old SP new SP name <email> SP time TAB msg LF */
1868 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
1869 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
1870 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
1871 !(email_end = strchr(sb.buf + 82, '>')) ||
1872 email_end[1] != ' ' ||
1873 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1874 !message || message[0] != ' ' ||
1875 (message[1] != '+' && message[1] != '-') ||
1876 !isdigit(message[2]) || !isdigit(message[3]) ||
1877 !isdigit(message[4]) || !isdigit(message[5]))
1878 continue; /* corrupt? */
1879 email_end[1] = '\0';
1880 tz = strtol(message + 1, NULL, 10);
1881 if (message[6] != '\t')
1882 message += 6;
1883 else
1884 message += 7;
1885 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
1886 cb_data);
1887 if (ret)
1888 break;
1889 }
1890 fclose(logfp);
1891 strbuf_release(&sb);
1892 return ret;
1893 }
1894
1895 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1896 {
1897 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1898 }
1899
1900 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1901 {
1902 DIR *dir = opendir(git_path("logs/%s", base));
1903 int retval = 0;
1904
1905 if (dir) {
1906 struct dirent *de;
1907 int baselen = strlen(base);
1908 char *log = xmalloc(baselen + 257);
1909
1910 memcpy(log, base, baselen);
1911 if (baselen && base[baselen-1] != '/')
1912 log[baselen++] = '/';
1913
1914 while ((de = readdir(dir)) != NULL) {
1915 struct stat st;
1916 int namelen;
1917
1918 if (de->d_name[0] == '.')
1919 continue;
1920 namelen = strlen(de->d_name);
1921 if (namelen > 255)
1922 continue;
1923 if (has_extension(de->d_name, ".lock"))
1924 continue;
1925 memcpy(log + baselen, de->d_name, namelen+1);
1926 if (stat(git_path("logs/%s", log), &st) < 0)
1927 continue;
1928 if (S_ISDIR(st.st_mode)) {
1929 retval = do_for_each_reflog(log, fn, cb_data);
1930 } else {
1931 unsigned char sha1[20];
1932 if (read_ref_full(log, sha1, 0, NULL))
1933 retval = error("bad ref for %s", log);
1934 else
1935 retval = fn(log, sha1, 0, cb_data);
1936 }
1937 if (retval)
1938 break;
1939 }
1940 free(log);
1941 closedir(dir);
1942 }
1943 else if (*base)
1944 return errno;
1945 return retval;
1946 }
1947
1948 int for_each_reflog(each_ref_fn fn, void *cb_data)
1949 {
1950 return do_for_each_reflog("", fn, cb_data);
1951 }
1952
1953 int update_ref(const char *action, const char *refname,
1954 const unsigned char *sha1, const unsigned char *oldval,
1955 int flags, enum action_on_err onerr)
1956 {
1957 static struct ref_lock *lock;
1958 lock = lock_any_ref_for_update(refname, oldval, flags);
1959 if (!lock) {
1960 const char *str = "Cannot lock the ref '%s'.";
1961 switch (onerr) {
1962 case MSG_ON_ERR: error(str, refname); break;
1963 case DIE_ON_ERR: die(str, refname); break;
1964 case QUIET_ON_ERR: break;
1965 }
1966 return 1;
1967 }
1968 if (write_ref_sha1(lock, sha1, action) < 0) {
1969 const char *str = "Cannot update the ref '%s'.";
1970 switch (onerr) {
1971 case MSG_ON_ERR: error(str, refname); break;
1972 case DIE_ON_ERR: die(str, refname); break;
1973 case QUIET_ON_ERR: break;
1974 }
1975 return 1;
1976 }
1977 return 0;
1978 }
1979
1980 int ref_exists(const char *refname)
1981 {
1982 unsigned char sha1[20];
1983 return !!resolve_ref(refname, sha1, 1, NULL);
1984 }
1985
1986 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1987 {
1988 for ( ; list; list = list->next)
1989 if (!strcmp(list->name, name))
1990 return (struct ref *)list;
1991 return NULL;
1992 }
1993
1994 /*
1995 * generate a format suitable for scanf from a ref_rev_parse_rules
1996 * rule, that is replace the "%.*s" spec with a "%s" spec
1997 */
1998 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1999 {
2000 char *spec;
2001
2002 spec = strstr(rule, "%.*s");
2003 if (!spec || strstr(spec + 4, "%.*s"))
2004 die("invalid rule in ref_rev_parse_rules: %s", rule);
2005
2006 /* copy all until spec */
2007 strncpy(scanf_fmt, rule, spec - rule);
2008 scanf_fmt[spec - rule] = '\0';
2009 /* copy new spec */
2010 strcat(scanf_fmt, "%s");
2011 /* copy remaining rule */
2012 strcat(scanf_fmt, spec + 4);
2013
2014 return;
2015 }
2016
2017 char *shorten_unambiguous_ref(const char *ref, int strict)
2018 {
2019 int i;
2020 static char **scanf_fmts;
2021 static int nr_rules;
2022 char *short_name;
2023
2024 /* pre generate scanf formats from ref_rev_parse_rules[] */
2025 if (!nr_rules) {
2026 size_t total_len = 0;
2027
2028 /* the rule list is NULL terminated, count them first */
2029 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
2030 /* no +1 because strlen("%s") < strlen("%.*s") */
2031 total_len += strlen(ref_rev_parse_rules[nr_rules]);
2032
2033 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
2034
2035 total_len = 0;
2036 for (i = 0; i < nr_rules; i++) {
2037 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
2038 + total_len;
2039 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
2040 total_len += strlen(ref_rev_parse_rules[i]);
2041 }
2042 }
2043
2044 /* bail out if there are no rules */
2045 if (!nr_rules)
2046 return xstrdup(ref);
2047
2048 /* buffer for scanf result, at most ref must fit */
2049 short_name = xstrdup(ref);
2050
2051 /* skip first rule, it will always match */
2052 for (i = nr_rules - 1; i > 0 ; --i) {
2053 int j;
2054 int rules_to_fail = i;
2055 int short_name_len;
2056
2057 if (1 != sscanf(ref, scanf_fmts[i], short_name))
2058 continue;
2059
2060 short_name_len = strlen(short_name);
2061
2062 /*
2063 * in strict mode, all (except the matched one) rules
2064 * must fail to resolve to a valid non-ambiguous ref
2065 */
2066 if (strict)
2067 rules_to_fail = nr_rules;
2068
2069 /*
2070 * check if the short name resolves to a valid ref,
2071 * but use only rules prior to the matched one
2072 */
2073 for (j = 0; j < rules_to_fail; j++) {
2074 const char *rule = ref_rev_parse_rules[j];
2075 char refname[PATH_MAX];
2076
2077 /* skip matched rule */
2078 if (i == j)
2079 continue;
2080
2081 /*
2082 * the short name is ambiguous, if it resolves
2083 * (with this previous rule) to a valid ref
2084 * read_ref() returns 0 on success
2085 */
2086 mksnpath(refname, sizeof(refname),
2087 rule, short_name_len, short_name);
2088 if (ref_exists(refname))
2089 break;
2090 }
2091
2092 /*
2093 * short name is non-ambiguous if all previous rules
2094 * haven't resolved to a valid ref
2095 */
2096 if (j == rules_to_fail)
2097 return short_name;
2098 }
2099
2100 free(short_name);
2101 return xstrdup(ref);
2102 }