Merge branch 'jk/build-with-asan'
[git/git.git] / refs.c
1 /*
2 * The backend-independent part of the reference module.
3 */
4
5 #include "cache.h"
6 #include "config.h"
7 #include "hashmap.h"
8 #include "lockfile.h"
9 #include "iterator.h"
10 #include "refs.h"
11 #include "refs/refs-internal.h"
12 #include "object.h"
13 #include "tag.h"
14 #include "submodule.h"
15 #include "worktree.h"
16
17 /*
18 * List of all available backends
19 */
20 static struct ref_storage_be *refs_backends = &refs_be_files;
21
22 static struct ref_storage_be *find_ref_storage_backend(const char *name)
23 {
24 struct ref_storage_be *be;
25 for (be = refs_backends; be; be = be->next)
26 if (!strcmp(be->name, name))
27 return be;
28 return NULL;
29 }
30
31 int ref_storage_backend_exists(const char *name)
32 {
33 return find_ref_storage_backend(name) != NULL;
34 }
35
36 /*
37 * How to handle various characters in refnames:
38 * 0: An acceptable character for refs
39 * 1: End-of-component
40 * 2: ., look for a preceding . to reject .. in refs
41 * 3: {, look for a preceding @ to reject @{ in refs
42 * 4: A bad character: ASCII control characters, and
43 * ":", "?", "[", "\", "^", "~", SP, or TAB
44 * 5: *, reject unless REFNAME_REFSPEC_PATTERN is set
45 */
46 static unsigned char refname_disposition[256] = {
47 1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
48 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
49 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 2, 1,
50 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4,
51 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
52 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 4, 0,
53 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
54 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 4
55 };
56
57 /*
58 * Try to read one refname component from the front of refname.
59 * Return the length of the component found, or -1 if the component is
60 * not legal. It is legal if it is something reasonable to have under
61 * ".git/refs/"; We do not like it if:
62 *
63 * - any path component of it begins with ".", or
64 * - it has double dots "..", or
65 * - it has ASCII control characters, or
66 * - it has ":", "?", "[", "\", "^", "~", SP, or TAB anywhere, or
67 * - it has "*" anywhere unless REFNAME_REFSPEC_PATTERN is set, or
68 * - it ends with a "/", or
69 * - it ends with ".lock", or
70 * - it contains a "@{" portion
71 */
72 static int check_refname_component(const char *refname, int *flags)
73 {
74 const char *cp;
75 char last = '\0';
76
77 for (cp = refname; ; cp++) {
78 int ch = *cp & 255;
79 unsigned char disp = refname_disposition[ch];
80 switch (disp) {
81 case 1:
82 goto out;
83 case 2:
84 if (last == '.')
85 return -1; /* Refname contains "..". */
86 break;
87 case 3:
88 if (last == '@')
89 return -1; /* Refname contains "@{". */
90 break;
91 case 4:
92 return -1;
93 case 5:
94 if (!(*flags & REFNAME_REFSPEC_PATTERN))
95 return -1; /* refspec can't be a pattern */
96
97 /*
98 * Unset the pattern flag so that we only accept
99 * a single asterisk for one side of refspec.
100 */
101 *flags &= ~ REFNAME_REFSPEC_PATTERN;
102 break;
103 }
104 last = ch;
105 }
106 out:
107 if (cp == refname)
108 return 0; /* Component has zero length. */
109 if (refname[0] == '.')
110 return -1; /* Component starts with '.'. */
111 if (cp - refname >= LOCK_SUFFIX_LEN &&
112 !memcmp(cp - LOCK_SUFFIX_LEN, LOCK_SUFFIX, LOCK_SUFFIX_LEN))
113 return -1; /* Refname ends with ".lock". */
114 return cp - refname;
115 }
116
117 int check_refname_format(const char *refname, int flags)
118 {
119 int component_len, component_count = 0;
120
121 if (!strcmp(refname, "@"))
122 /* Refname is a single character '@'. */
123 return -1;
124
125 while (1) {
126 /* We are at the start of a path component. */
127 component_len = check_refname_component(refname, &flags);
128 if (component_len <= 0)
129 return -1;
130
131 component_count++;
132 if (refname[component_len] == '\0')
133 break;
134 /* Skip to next component. */
135 refname += component_len + 1;
136 }
137
138 if (refname[component_len - 1] == '.')
139 return -1; /* Refname ends with '.'. */
140 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
141 return -1; /* Refname has only one component. */
142 return 0;
143 }
144
145 int refname_is_safe(const char *refname)
146 {
147 const char *rest;
148
149 if (skip_prefix(refname, "refs/", &rest)) {
150 char *buf;
151 int result;
152 size_t restlen = strlen(rest);
153
154 /* rest must not be empty, or start or end with "/" */
155 if (!restlen || *rest == '/' || rest[restlen - 1] == '/')
156 return 0;
157
158 /*
159 * Does the refname try to escape refs/?
160 * For example: refs/foo/../bar is safe but refs/foo/../../bar
161 * is not.
162 */
163 buf = xmallocz(restlen);
164 result = !normalize_path_copy(buf, rest) && !strcmp(buf, rest);
165 free(buf);
166 return result;
167 }
168
169 do {
170 if (!isupper(*refname) && *refname != '_')
171 return 0;
172 refname++;
173 } while (*refname);
174 return 1;
175 }
176
177 char *refs_resolve_refdup(struct ref_store *refs,
178 const char *refname, int resolve_flags,
179 unsigned char *sha1, int *flags)
180 {
181 const char *result;
182
183 result = refs_resolve_ref_unsafe(refs, refname, resolve_flags,
184 sha1, flags);
185 return xstrdup_or_null(result);
186 }
187
188 char *resolve_refdup(const char *refname, int resolve_flags,
189 unsigned char *sha1, int *flags)
190 {
191 return refs_resolve_refdup(get_main_ref_store(),
192 refname, resolve_flags,
193 sha1, flags);
194 }
195
196 /* The argument to filter_refs */
197 struct ref_filter {
198 const char *pattern;
199 each_ref_fn *fn;
200 void *cb_data;
201 };
202
203 int refs_read_ref_full(struct ref_store *refs, const char *refname,
204 int resolve_flags, unsigned char *sha1, int *flags)
205 {
206 if (refs_resolve_ref_unsafe(refs, refname, resolve_flags, sha1, flags))
207 return 0;
208 return -1;
209 }
210
211 int read_ref_full(const char *refname, int resolve_flags, unsigned char *sha1, int *flags)
212 {
213 return refs_read_ref_full(get_main_ref_store(), refname,
214 resolve_flags, sha1, flags);
215 }
216
217 int read_ref(const char *refname, unsigned char *sha1)
218 {
219 return read_ref_full(refname, RESOLVE_REF_READING, sha1, NULL);
220 }
221
222 int ref_exists(const char *refname)
223 {
224 unsigned char sha1[20];
225 return !!resolve_ref_unsafe(refname, RESOLVE_REF_READING, sha1, NULL);
226 }
227
228 static int filter_refs(const char *refname, const struct object_id *oid,
229 int flags, void *data)
230 {
231 struct ref_filter *filter = (struct ref_filter *)data;
232
233 if (wildmatch(filter->pattern, refname, 0))
234 return 0;
235 return filter->fn(refname, oid, flags, filter->cb_data);
236 }
237
238 enum peel_status peel_object(const unsigned char *name, unsigned char *sha1)
239 {
240 struct object *o = lookup_unknown_object(name);
241
242 if (o->type == OBJ_NONE) {
243 int type = sha1_object_info(name, NULL);
244 if (type < 0 || !object_as_type(o, type, 0))
245 return PEEL_INVALID;
246 }
247
248 if (o->type != OBJ_TAG)
249 return PEEL_NON_TAG;
250
251 o = deref_tag_noverify(o);
252 if (!o)
253 return PEEL_INVALID;
254
255 hashcpy(sha1, o->oid.hash);
256 return PEEL_PEELED;
257 }
258
259 struct warn_if_dangling_data {
260 FILE *fp;
261 const char *refname;
262 const struct string_list *refnames;
263 const char *msg_fmt;
264 };
265
266 static int warn_if_dangling_symref(const char *refname, const struct object_id *oid,
267 int flags, void *cb_data)
268 {
269 struct warn_if_dangling_data *d = cb_data;
270 const char *resolves_to;
271 struct object_id junk;
272
273 if (!(flags & REF_ISSYMREF))
274 return 0;
275
276 resolves_to = resolve_ref_unsafe(refname, 0, junk.hash, NULL);
277 if (!resolves_to
278 || (d->refname
279 ? strcmp(resolves_to, d->refname)
280 : !string_list_has_string(d->refnames, resolves_to))) {
281 return 0;
282 }
283
284 fprintf(d->fp, d->msg_fmt, refname);
285 fputc('\n', d->fp);
286 return 0;
287 }
288
289 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
290 {
291 struct warn_if_dangling_data data;
292
293 data.fp = fp;
294 data.refname = refname;
295 data.refnames = NULL;
296 data.msg_fmt = msg_fmt;
297 for_each_rawref(warn_if_dangling_symref, &data);
298 }
299
300 void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames)
301 {
302 struct warn_if_dangling_data data;
303
304 data.fp = fp;
305 data.refname = NULL;
306 data.refnames = refnames;
307 data.msg_fmt = msg_fmt;
308 for_each_rawref(warn_if_dangling_symref, &data);
309 }
310
311 int refs_for_each_tag_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
312 {
313 return refs_for_each_ref_in(refs, "refs/tags/", fn, cb_data);
314 }
315
316 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
317 {
318 return refs_for_each_tag_ref(get_main_ref_store(), fn, cb_data);
319 }
320
321 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
322 {
323 return refs_for_each_tag_ref(get_submodule_ref_store(submodule),
324 fn, cb_data);
325 }
326
327 int refs_for_each_branch_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
328 {
329 return refs_for_each_ref_in(refs, "refs/heads/", fn, cb_data);
330 }
331
332 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
333 {
334 return refs_for_each_branch_ref(get_main_ref_store(), fn, cb_data);
335 }
336
337 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
338 {
339 return refs_for_each_branch_ref(get_submodule_ref_store(submodule),
340 fn, cb_data);
341 }
342
343 int refs_for_each_remote_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
344 {
345 return refs_for_each_ref_in(refs, "refs/remotes/", fn, cb_data);
346 }
347
348 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
349 {
350 return refs_for_each_remote_ref(get_main_ref_store(), fn, cb_data);
351 }
352
353 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
354 {
355 return refs_for_each_remote_ref(get_submodule_ref_store(submodule),
356 fn, cb_data);
357 }
358
359 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
360 {
361 struct strbuf buf = STRBUF_INIT;
362 int ret = 0;
363 struct object_id oid;
364 int flag;
365
366 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
367 if (!read_ref_full(buf.buf, RESOLVE_REF_READING, oid.hash, &flag))
368 ret = fn(buf.buf, &oid, flag, cb_data);
369 strbuf_release(&buf);
370
371 return ret;
372 }
373
374 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
375 const char *prefix, void *cb_data)
376 {
377 struct strbuf real_pattern = STRBUF_INIT;
378 struct ref_filter filter;
379 int ret;
380
381 if (!prefix && !starts_with(pattern, "refs/"))
382 strbuf_addstr(&real_pattern, "refs/");
383 else if (prefix)
384 strbuf_addstr(&real_pattern, prefix);
385 strbuf_addstr(&real_pattern, pattern);
386
387 if (!has_glob_specials(pattern)) {
388 /* Append implied '/' '*' if not present. */
389 strbuf_complete(&real_pattern, '/');
390 /* No need to check for '*', there is none. */
391 strbuf_addch(&real_pattern, '*');
392 }
393
394 filter.pattern = real_pattern.buf;
395 filter.fn = fn;
396 filter.cb_data = cb_data;
397 ret = for_each_ref(filter_refs, &filter);
398
399 strbuf_release(&real_pattern);
400 return ret;
401 }
402
403 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
404 {
405 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
406 }
407
408 const char *prettify_refname(const char *name)
409 {
410 if (skip_prefix(name, "refs/heads/", &name) ||
411 skip_prefix(name, "refs/tags/", &name) ||
412 skip_prefix(name, "refs/remotes/", &name))
413 ; /* nothing */
414 return name;
415 }
416
417 static const char *ref_rev_parse_rules[] = {
418 "%.*s",
419 "refs/%.*s",
420 "refs/tags/%.*s",
421 "refs/heads/%.*s",
422 "refs/remotes/%.*s",
423 "refs/remotes/%.*s/HEAD",
424 NULL
425 };
426
427 int refname_match(const char *abbrev_name, const char *full_name)
428 {
429 const char **p;
430 const int abbrev_name_len = strlen(abbrev_name);
431
432 for (p = ref_rev_parse_rules; *p; p++) {
433 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
434 return 1;
435 }
436 }
437
438 return 0;
439 }
440
441 /*
442 * *string and *len will only be substituted, and *string returned (for
443 * later free()ing) if the string passed in is a magic short-hand form
444 * to name a branch.
445 */
446 static char *substitute_branch_name(const char **string, int *len)
447 {
448 struct strbuf buf = STRBUF_INIT;
449 int ret = interpret_branch_name(*string, *len, &buf, 0);
450
451 if (ret == *len) {
452 size_t size;
453 *string = strbuf_detach(&buf, &size);
454 *len = size;
455 return (char *)*string;
456 }
457
458 return NULL;
459 }
460
461 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
462 {
463 char *last_branch = substitute_branch_name(&str, &len);
464 int refs_found = expand_ref(str, len, sha1, ref);
465 free(last_branch);
466 return refs_found;
467 }
468
469 int expand_ref(const char *str, int len, unsigned char *sha1, char **ref)
470 {
471 const char **p, *r;
472 int refs_found = 0;
473 struct strbuf fullref = STRBUF_INIT;
474
475 *ref = NULL;
476 for (p = ref_rev_parse_rules; *p; p++) {
477 unsigned char sha1_from_ref[20];
478 unsigned char *this_result;
479 int flag;
480
481 this_result = refs_found ? sha1_from_ref : sha1;
482 strbuf_reset(&fullref);
483 strbuf_addf(&fullref, *p, len, str);
484 r = resolve_ref_unsafe(fullref.buf, RESOLVE_REF_READING,
485 this_result, &flag);
486 if (r) {
487 if (!refs_found++)
488 *ref = xstrdup(r);
489 if (!warn_ambiguous_refs)
490 break;
491 } else if ((flag & REF_ISSYMREF) && strcmp(fullref.buf, "HEAD")) {
492 warning("ignoring dangling symref %s.", fullref.buf);
493 } else if ((flag & REF_ISBROKEN) && strchr(fullref.buf, '/')) {
494 warning("ignoring broken ref %s.", fullref.buf);
495 }
496 }
497 strbuf_release(&fullref);
498 return refs_found;
499 }
500
501 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
502 {
503 char *last_branch = substitute_branch_name(&str, &len);
504 const char **p;
505 int logs_found = 0;
506 struct strbuf path = STRBUF_INIT;
507
508 *log = NULL;
509 for (p = ref_rev_parse_rules; *p; p++) {
510 unsigned char hash[20];
511 const char *ref, *it;
512
513 strbuf_reset(&path);
514 strbuf_addf(&path, *p, len, str);
515 ref = resolve_ref_unsafe(path.buf, RESOLVE_REF_READING,
516 hash, NULL);
517 if (!ref)
518 continue;
519 if (reflog_exists(path.buf))
520 it = path.buf;
521 else if (strcmp(ref, path.buf) && reflog_exists(ref))
522 it = ref;
523 else
524 continue;
525 if (!logs_found++) {
526 *log = xstrdup(it);
527 hashcpy(sha1, hash);
528 }
529 if (!warn_ambiguous_refs)
530 break;
531 }
532 strbuf_release(&path);
533 free(last_branch);
534 return logs_found;
535 }
536
537 static int is_per_worktree_ref(const char *refname)
538 {
539 return !strcmp(refname, "HEAD") ||
540 starts_with(refname, "refs/bisect/");
541 }
542
543 static int is_pseudoref_syntax(const char *refname)
544 {
545 const char *c;
546
547 for (c = refname; *c; c++) {
548 if (!isupper(*c) && *c != '-' && *c != '_')
549 return 0;
550 }
551
552 return 1;
553 }
554
555 enum ref_type ref_type(const char *refname)
556 {
557 if (is_per_worktree_ref(refname))
558 return REF_TYPE_PER_WORKTREE;
559 if (is_pseudoref_syntax(refname))
560 return REF_TYPE_PSEUDOREF;
561 return REF_TYPE_NORMAL;
562 }
563
564 static int write_pseudoref(const char *pseudoref, const unsigned char *sha1,
565 const unsigned char *old_sha1, struct strbuf *err)
566 {
567 const char *filename;
568 int fd;
569 static struct lock_file lock;
570 struct strbuf buf = STRBUF_INIT;
571 int ret = -1;
572
573 strbuf_addf(&buf, "%s\n", sha1_to_hex(sha1));
574
575 filename = git_path("%s", pseudoref);
576 fd = hold_lock_file_for_update(&lock, filename, LOCK_DIE_ON_ERROR);
577 if (fd < 0) {
578 strbuf_addf(err, "could not open '%s' for writing: %s",
579 filename, strerror(errno));
580 return -1;
581 }
582
583 if (old_sha1) {
584 unsigned char actual_old_sha1[20];
585
586 if (read_ref(pseudoref, actual_old_sha1))
587 die("could not read ref '%s'", pseudoref);
588 if (hashcmp(actual_old_sha1, old_sha1)) {
589 strbuf_addf(err, "unexpected sha1 when writing '%s'", pseudoref);
590 rollback_lock_file(&lock);
591 goto done;
592 }
593 }
594
595 if (write_in_full(fd, buf.buf, buf.len) != buf.len) {
596 strbuf_addf(err, "could not write to '%s'", filename);
597 rollback_lock_file(&lock);
598 goto done;
599 }
600
601 commit_lock_file(&lock);
602 ret = 0;
603 done:
604 strbuf_release(&buf);
605 return ret;
606 }
607
608 static int delete_pseudoref(const char *pseudoref, const unsigned char *old_sha1)
609 {
610 static struct lock_file lock;
611 const char *filename;
612
613 filename = git_path("%s", pseudoref);
614
615 if (old_sha1 && !is_null_sha1(old_sha1)) {
616 int fd;
617 unsigned char actual_old_sha1[20];
618
619 fd = hold_lock_file_for_update(&lock, filename,
620 LOCK_DIE_ON_ERROR);
621 if (fd < 0)
622 die_errno(_("Could not open '%s' for writing"), filename);
623 if (read_ref(pseudoref, actual_old_sha1))
624 die("could not read ref '%s'", pseudoref);
625 if (hashcmp(actual_old_sha1, old_sha1)) {
626 warning("Unexpected sha1 when deleting %s", pseudoref);
627 rollback_lock_file(&lock);
628 return -1;
629 }
630
631 unlink(filename);
632 rollback_lock_file(&lock);
633 } else {
634 unlink(filename);
635 }
636
637 return 0;
638 }
639
640 int refs_delete_ref(struct ref_store *refs, const char *msg,
641 const char *refname,
642 const unsigned char *old_sha1,
643 unsigned int flags)
644 {
645 struct ref_transaction *transaction;
646 struct strbuf err = STRBUF_INIT;
647
648 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
649 assert(refs == get_main_ref_store());
650 return delete_pseudoref(refname, old_sha1);
651 }
652
653 transaction = ref_store_transaction_begin(refs, &err);
654 if (!transaction ||
655 ref_transaction_delete(transaction, refname, old_sha1,
656 flags, msg, &err) ||
657 ref_transaction_commit(transaction, &err)) {
658 error("%s", err.buf);
659 ref_transaction_free(transaction);
660 strbuf_release(&err);
661 return 1;
662 }
663 ref_transaction_free(transaction);
664 strbuf_release(&err);
665 return 0;
666 }
667
668 int delete_ref(const char *msg, const char *refname,
669 const unsigned char *old_sha1, unsigned int flags)
670 {
671 return refs_delete_ref(get_main_ref_store(), msg, refname,
672 old_sha1, flags);
673 }
674
675 int copy_reflog_msg(char *buf, const char *msg)
676 {
677 char *cp = buf;
678 char c;
679 int wasspace = 1;
680
681 *cp++ = '\t';
682 while ((c = *msg++)) {
683 if (wasspace && isspace(c))
684 continue;
685 wasspace = isspace(c);
686 if (wasspace)
687 c = ' ';
688 *cp++ = c;
689 }
690 while (buf < cp && isspace(cp[-1]))
691 cp--;
692 *cp++ = '\n';
693 return cp - buf;
694 }
695
696 int should_autocreate_reflog(const char *refname)
697 {
698 switch (log_all_ref_updates) {
699 case LOG_REFS_ALWAYS:
700 return 1;
701 case LOG_REFS_NORMAL:
702 return starts_with(refname, "refs/heads/") ||
703 starts_with(refname, "refs/remotes/") ||
704 starts_with(refname, "refs/notes/") ||
705 !strcmp(refname, "HEAD");
706 default:
707 return 0;
708 }
709 }
710
711 int is_branch(const char *refname)
712 {
713 return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
714 }
715
716 struct read_ref_at_cb {
717 const char *refname;
718 timestamp_t at_time;
719 int cnt;
720 int reccnt;
721 unsigned char *sha1;
722 int found_it;
723
724 unsigned char osha1[20];
725 unsigned char nsha1[20];
726 int tz;
727 timestamp_t date;
728 char **msg;
729 timestamp_t *cutoff_time;
730 int *cutoff_tz;
731 int *cutoff_cnt;
732 };
733
734 static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
735 const char *email, timestamp_t timestamp, int tz,
736 const char *message, void *cb_data)
737 {
738 struct read_ref_at_cb *cb = cb_data;
739
740 cb->reccnt++;
741 cb->tz = tz;
742 cb->date = timestamp;
743
744 if (timestamp <= cb->at_time || cb->cnt == 0) {
745 if (cb->msg)
746 *cb->msg = xstrdup(message);
747 if (cb->cutoff_time)
748 *cb->cutoff_time = timestamp;
749 if (cb->cutoff_tz)
750 *cb->cutoff_tz = tz;
751 if (cb->cutoff_cnt)
752 *cb->cutoff_cnt = cb->reccnt - 1;
753 /*
754 * we have not yet updated cb->[n|o]sha1 so they still
755 * hold the values for the previous record.
756 */
757 if (!is_null_sha1(cb->osha1)) {
758 hashcpy(cb->sha1, noid->hash);
759 if (hashcmp(cb->osha1, noid->hash))
760 warning("Log for ref %s has gap after %s.",
761 cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
762 }
763 else if (cb->date == cb->at_time)
764 hashcpy(cb->sha1, noid->hash);
765 else if (hashcmp(noid->hash, cb->sha1))
766 warning("Log for ref %s unexpectedly ended on %s.",
767 cb->refname, show_date(cb->date, cb->tz,
768 DATE_MODE(RFC2822)));
769 hashcpy(cb->osha1, ooid->hash);
770 hashcpy(cb->nsha1, noid->hash);
771 cb->found_it = 1;
772 return 1;
773 }
774 hashcpy(cb->osha1, ooid->hash);
775 hashcpy(cb->nsha1, noid->hash);
776 if (cb->cnt > 0)
777 cb->cnt--;
778 return 0;
779 }
780
781 static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
782 const char *email, timestamp_t timestamp,
783 int tz, const char *message, void *cb_data)
784 {
785 struct read_ref_at_cb *cb = cb_data;
786
787 if (cb->msg)
788 *cb->msg = xstrdup(message);
789 if (cb->cutoff_time)
790 *cb->cutoff_time = timestamp;
791 if (cb->cutoff_tz)
792 *cb->cutoff_tz = tz;
793 if (cb->cutoff_cnt)
794 *cb->cutoff_cnt = cb->reccnt;
795 hashcpy(cb->sha1, ooid->hash);
796 if (is_null_sha1(cb->sha1))
797 hashcpy(cb->sha1, noid->hash);
798 /* We just want the first entry */
799 return 1;
800 }
801
802 int read_ref_at(const char *refname, unsigned int flags, timestamp_t at_time, int cnt,
803 unsigned char *sha1, char **msg,
804 timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
805 {
806 struct read_ref_at_cb cb;
807
808 memset(&cb, 0, sizeof(cb));
809 cb.refname = refname;
810 cb.at_time = at_time;
811 cb.cnt = cnt;
812 cb.msg = msg;
813 cb.cutoff_time = cutoff_time;
814 cb.cutoff_tz = cutoff_tz;
815 cb.cutoff_cnt = cutoff_cnt;
816 cb.sha1 = sha1;
817
818 for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
819
820 if (!cb.reccnt) {
821 if (flags & GET_SHA1_QUIETLY)
822 exit(128);
823 else
824 die("Log for %s is empty.", refname);
825 }
826 if (cb.found_it)
827 return 0;
828
829 for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
830
831 return 1;
832 }
833
834 struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs,
835 struct strbuf *err)
836 {
837 struct ref_transaction *tr;
838 assert(err);
839
840 tr = xcalloc(1, sizeof(struct ref_transaction));
841 tr->ref_store = refs;
842 return tr;
843 }
844
845 struct ref_transaction *ref_transaction_begin(struct strbuf *err)
846 {
847 return ref_store_transaction_begin(get_main_ref_store(), err);
848 }
849
850 void ref_transaction_free(struct ref_transaction *transaction)
851 {
852 size_t i;
853
854 if (!transaction)
855 return;
856
857 switch (transaction->state) {
858 case REF_TRANSACTION_OPEN:
859 case REF_TRANSACTION_CLOSED:
860 /* OK */
861 break;
862 case REF_TRANSACTION_PREPARED:
863 die("BUG: free called on a prepared reference transaction");
864 break;
865 default:
866 die("BUG: unexpected reference transaction state");
867 break;
868 }
869
870 for (i = 0; i < transaction->nr; i++) {
871 free(transaction->updates[i]->msg);
872 free(transaction->updates[i]);
873 }
874 free(transaction->updates);
875 free(transaction);
876 }
877
878 struct ref_update *ref_transaction_add_update(
879 struct ref_transaction *transaction,
880 const char *refname, unsigned int flags,
881 const unsigned char *new_sha1,
882 const unsigned char *old_sha1,
883 const char *msg)
884 {
885 struct ref_update *update;
886
887 if (transaction->state != REF_TRANSACTION_OPEN)
888 die("BUG: update called for transaction that is not open");
889
890 if ((flags & REF_ISPRUNING) && !(flags & REF_NODEREF))
891 die("BUG: REF_ISPRUNING set without REF_NODEREF");
892
893 FLEX_ALLOC_STR(update, refname, refname);
894 ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
895 transaction->updates[transaction->nr++] = update;
896
897 update->flags = flags;
898
899 if (flags & REF_HAVE_NEW)
900 hashcpy(update->new_oid.hash, new_sha1);
901 if (flags & REF_HAVE_OLD)
902 hashcpy(update->old_oid.hash, old_sha1);
903 update->msg = xstrdup_or_null(msg);
904 return update;
905 }
906
907 int ref_transaction_update(struct ref_transaction *transaction,
908 const char *refname,
909 const unsigned char *new_sha1,
910 const unsigned char *old_sha1,
911 unsigned int flags, const char *msg,
912 struct strbuf *err)
913 {
914 assert(err);
915
916 if ((new_sha1 && !is_null_sha1(new_sha1)) ?
917 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
918 !refname_is_safe(refname)) {
919 strbuf_addf(err, "refusing to update ref with bad name '%s'",
920 refname);
921 return -1;
922 }
923
924 flags |= (new_sha1 ? REF_HAVE_NEW : 0) | (old_sha1 ? REF_HAVE_OLD : 0);
925
926 ref_transaction_add_update(transaction, refname, flags,
927 new_sha1, old_sha1, msg);
928 return 0;
929 }
930
931 int ref_transaction_create(struct ref_transaction *transaction,
932 const char *refname,
933 const unsigned char *new_sha1,
934 unsigned int flags, const char *msg,
935 struct strbuf *err)
936 {
937 if (!new_sha1 || is_null_sha1(new_sha1))
938 die("BUG: create called without valid new_sha1");
939 return ref_transaction_update(transaction, refname, new_sha1,
940 null_sha1, flags, msg, err);
941 }
942
943 int ref_transaction_delete(struct ref_transaction *transaction,
944 const char *refname,
945 const unsigned char *old_sha1,
946 unsigned int flags, const char *msg,
947 struct strbuf *err)
948 {
949 if (old_sha1 && is_null_sha1(old_sha1))
950 die("BUG: delete called with old_sha1 set to zeros");
951 return ref_transaction_update(transaction, refname,
952 null_sha1, old_sha1,
953 flags, msg, err);
954 }
955
956 int ref_transaction_verify(struct ref_transaction *transaction,
957 const char *refname,
958 const unsigned char *old_sha1,
959 unsigned int flags,
960 struct strbuf *err)
961 {
962 if (!old_sha1)
963 die("BUG: verify called with old_sha1 set to NULL");
964 return ref_transaction_update(transaction, refname,
965 NULL, old_sha1,
966 flags, NULL, err);
967 }
968
969 int update_ref_oid(const char *msg, const char *refname,
970 const struct object_id *new_oid, const struct object_id *old_oid,
971 unsigned int flags, enum action_on_err onerr)
972 {
973 return update_ref(msg, refname, new_oid ? new_oid->hash : NULL,
974 old_oid ? old_oid->hash : NULL, flags, onerr);
975 }
976
977 int refs_update_ref(struct ref_store *refs, const char *msg,
978 const char *refname, const unsigned char *new_sha1,
979 const unsigned char *old_sha1, unsigned int flags,
980 enum action_on_err onerr)
981 {
982 struct ref_transaction *t = NULL;
983 struct strbuf err = STRBUF_INIT;
984 int ret = 0;
985
986 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
987 assert(refs == get_main_ref_store());
988 ret = write_pseudoref(refname, new_sha1, old_sha1, &err);
989 } else {
990 t = ref_store_transaction_begin(refs, &err);
991 if (!t ||
992 ref_transaction_update(t, refname, new_sha1, old_sha1,
993 flags, msg, &err) ||
994 ref_transaction_commit(t, &err)) {
995 ret = 1;
996 ref_transaction_free(t);
997 }
998 }
999 if (ret) {
1000 const char *str = "update_ref failed for ref '%s': %s";
1001
1002 switch (onerr) {
1003 case UPDATE_REFS_MSG_ON_ERR:
1004 error(str, refname, err.buf);
1005 break;
1006 case UPDATE_REFS_DIE_ON_ERR:
1007 die(str, refname, err.buf);
1008 break;
1009 case UPDATE_REFS_QUIET_ON_ERR:
1010 break;
1011 }
1012 strbuf_release(&err);
1013 return 1;
1014 }
1015 strbuf_release(&err);
1016 if (t)
1017 ref_transaction_free(t);
1018 return 0;
1019 }
1020
1021 int update_ref(const char *msg, const char *refname,
1022 const unsigned char *new_sha1,
1023 const unsigned char *old_sha1,
1024 unsigned int flags, enum action_on_err onerr)
1025 {
1026 return refs_update_ref(get_main_ref_store(), msg, refname, new_sha1,
1027 old_sha1, flags, onerr);
1028 }
1029
1030 char *shorten_unambiguous_ref(const char *refname, int strict)
1031 {
1032 int i;
1033 static char **scanf_fmts;
1034 static int nr_rules;
1035 char *short_name;
1036 struct strbuf resolved_buf = STRBUF_INIT;
1037
1038 if (!nr_rules) {
1039 /*
1040 * Pre-generate scanf formats from ref_rev_parse_rules[].
1041 * Generate a format suitable for scanf from a
1042 * ref_rev_parse_rules rule by interpolating "%s" at the
1043 * location of the "%.*s".
1044 */
1045 size_t total_len = 0;
1046 size_t offset = 0;
1047
1048 /* the rule list is NULL terminated, count them first */
1049 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
1050 /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
1051 total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
1052
1053 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
1054
1055 offset = 0;
1056 for (i = 0; i < nr_rules; i++) {
1057 assert(offset < total_len);
1058 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
1059 offset += snprintf(scanf_fmts[i], total_len - offset,
1060 ref_rev_parse_rules[i], 2, "%s") + 1;
1061 }
1062 }
1063
1064 /* bail out if there are no rules */
1065 if (!nr_rules)
1066 return xstrdup(refname);
1067
1068 /* buffer for scanf result, at most refname must fit */
1069 short_name = xstrdup(refname);
1070
1071 /* skip first rule, it will always match */
1072 for (i = nr_rules - 1; i > 0 ; --i) {
1073 int j;
1074 int rules_to_fail = i;
1075 int short_name_len;
1076
1077 if (1 != sscanf(refname, scanf_fmts[i], short_name))
1078 continue;
1079
1080 short_name_len = strlen(short_name);
1081
1082 /*
1083 * in strict mode, all (except the matched one) rules
1084 * must fail to resolve to a valid non-ambiguous ref
1085 */
1086 if (strict)
1087 rules_to_fail = nr_rules;
1088
1089 /*
1090 * check if the short name resolves to a valid ref,
1091 * but use only rules prior to the matched one
1092 */
1093 for (j = 0; j < rules_to_fail; j++) {
1094 const char *rule = ref_rev_parse_rules[j];
1095
1096 /* skip matched rule */
1097 if (i == j)
1098 continue;
1099
1100 /*
1101 * the short name is ambiguous, if it resolves
1102 * (with this previous rule) to a valid ref
1103 * read_ref() returns 0 on success
1104 */
1105 strbuf_reset(&resolved_buf);
1106 strbuf_addf(&resolved_buf, rule,
1107 short_name_len, short_name);
1108 if (ref_exists(resolved_buf.buf))
1109 break;
1110 }
1111
1112 /*
1113 * short name is non-ambiguous if all previous rules
1114 * haven't resolved to a valid ref
1115 */
1116 if (j == rules_to_fail) {
1117 strbuf_release(&resolved_buf);
1118 return short_name;
1119 }
1120 }
1121
1122 strbuf_release(&resolved_buf);
1123 free(short_name);
1124 return xstrdup(refname);
1125 }
1126
1127 static struct string_list *hide_refs;
1128
1129 int parse_hide_refs_config(const char *var, const char *value, const char *section)
1130 {
1131 const char *key;
1132 if (!strcmp("transfer.hiderefs", var) ||
1133 (!parse_config_key(var, section, NULL, NULL, &key) &&
1134 !strcmp(key, "hiderefs"))) {
1135 char *ref;
1136 int len;
1137
1138 if (!value)
1139 return config_error_nonbool(var);
1140 ref = xstrdup(value);
1141 len = strlen(ref);
1142 while (len && ref[len - 1] == '/')
1143 ref[--len] = '\0';
1144 if (!hide_refs) {
1145 hide_refs = xcalloc(1, sizeof(*hide_refs));
1146 hide_refs->strdup_strings = 1;
1147 }
1148 string_list_append(hide_refs, ref);
1149 }
1150 return 0;
1151 }
1152
1153 int ref_is_hidden(const char *refname, const char *refname_full)
1154 {
1155 int i;
1156
1157 if (!hide_refs)
1158 return 0;
1159 for (i = hide_refs->nr - 1; i >= 0; i--) {
1160 const char *match = hide_refs->items[i].string;
1161 const char *subject;
1162 int neg = 0;
1163 int len;
1164
1165 if (*match == '!') {
1166 neg = 1;
1167 match++;
1168 }
1169
1170 if (*match == '^') {
1171 subject = refname_full;
1172 match++;
1173 } else {
1174 subject = refname;
1175 }
1176
1177 /* refname can be NULL when namespaces are used. */
1178 if (!subject || !starts_with(subject, match))
1179 continue;
1180 len = strlen(match);
1181 if (!subject[len] || subject[len] == '/')
1182 return !neg;
1183 }
1184 return 0;
1185 }
1186
1187 const char *find_descendant_ref(const char *dirname,
1188 const struct string_list *extras,
1189 const struct string_list *skip)
1190 {
1191 int pos;
1192
1193 if (!extras)
1194 return NULL;
1195
1196 /*
1197 * Look at the place where dirname would be inserted into
1198 * extras. If there is an entry at that position that starts
1199 * with dirname (remember, dirname includes the trailing
1200 * slash) and is not in skip, then we have a conflict.
1201 */
1202 for (pos = string_list_find_insert_index(extras, dirname, 0);
1203 pos < extras->nr; pos++) {
1204 const char *extra_refname = extras->items[pos].string;
1205
1206 if (!starts_with(extra_refname, dirname))
1207 break;
1208
1209 if (!skip || !string_list_has_string(skip, extra_refname))
1210 return extra_refname;
1211 }
1212 return NULL;
1213 }
1214
1215 int refs_rename_ref_available(struct ref_store *refs,
1216 const char *old_refname,
1217 const char *new_refname)
1218 {
1219 struct string_list skip = STRING_LIST_INIT_NODUP;
1220 struct strbuf err = STRBUF_INIT;
1221 int ok;
1222
1223 string_list_insert(&skip, old_refname);
1224 ok = !refs_verify_refname_available(refs, new_refname,
1225 NULL, &skip, &err);
1226 if (!ok)
1227 error("%s", err.buf);
1228
1229 string_list_clear(&skip, 0);
1230 strbuf_release(&err);
1231 return ok;
1232 }
1233
1234 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1235 {
1236 struct object_id oid;
1237 int flag;
1238
1239 if (submodule) {
1240 if (resolve_gitlink_ref(submodule, "HEAD", oid.hash) == 0)
1241 return fn("HEAD", &oid, 0, cb_data);
1242
1243 return 0;
1244 }
1245
1246 if (!read_ref_full("HEAD", RESOLVE_REF_READING, oid.hash, &flag))
1247 return fn("HEAD", &oid, flag, cb_data);
1248
1249 return 0;
1250 }
1251
1252 int head_ref(each_ref_fn fn, void *cb_data)
1253 {
1254 return head_ref_submodule(NULL, fn, cb_data);
1255 }
1256
1257 struct ref_iterator *refs_ref_iterator_begin(
1258 struct ref_store *refs,
1259 const char *prefix, int trim, int flags)
1260 {
1261 struct ref_iterator *iter;
1262
1263 if (ref_paranoia < 0)
1264 ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
1265 if (ref_paranoia)
1266 flags |= DO_FOR_EACH_INCLUDE_BROKEN;
1267
1268 iter = refs->be->iterator_begin(refs, prefix, flags);
1269
1270 /*
1271 * `iterator_begin()` already takes care of prefix, but we
1272 * might need to do some trimming:
1273 */
1274 if (trim)
1275 iter = prefix_ref_iterator_begin(iter, "", trim);
1276
1277 return iter;
1278 }
1279
1280 /*
1281 * Call fn for each reference in the specified submodule for which the
1282 * refname begins with prefix. If trim is non-zero, then trim that
1283 * many characters off the beginning of each refname before passing
1284 * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1285 * include broken references in the iteration. If fn ever returns a
1286 * non-zero value, stop the iteration and return that value;
1287 * otherwise, return 0.
1288 */
1289 static int do_for_each_ref(struct ref_store *refs, const char *prefix,
1290 each_ref_fn fn, int trim, int flags, void *cb_data)
1291 {
1292 struct ref_iterator *iter;
1293
1294 if (!refs)
1295 return 0;
1296
1297 iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1298
1299 return do_for_each_ref_iterator(iter, fn, cb_data);
1300 }
1301
1302 int refs_for_each_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1303 {
1304 return do_for_each_ref(refs, "", fn, 0, 0, cb_data);
1305 }
1306
1307 int for_each_ref(each_ref_fn fn, void *cb_data)
1308 {
1309 return refs_for_each_ref(get_main_ref_store(), fn, cb_data);
1310 }
1311
1312 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1313 {
1314 return refs_for_each_ref(get_submodule_ref_store(submodule), fn, cb_data);
1315 }
1316
1317 int refs_for_each_ref_in(struct ref_store *refs, const char *prefix,
1318 each_ref_fn fn, void *cb_data)
1319 {
1320 return do_for_each_ref(refs, prefix, fn, strlen(prefix), 0, cb_data);
1321 }
1322
1323 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1324 {
1325 return refs_for_each_ref_in(get_main_ref_store(), prefix, fn, cb_data);
1326 }
1327
1328 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1329 {
1330 unsigned int flag = 0;
1331
1332 if (broken)
1333 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1334 return do_for_each_ref(get_main_ref_store(),
1335 prefix, fn, 0, flag, cb_data);
1336 }
1337
1338 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1339 each_ref_fn fn, void *cb_data)
1340 {
1341 return refs_for_each_ref_in(get_submodule_ref_store(submodule),
1342 prefix, fn, cb_data);
1343 }
1344
1345 int for_each_fullref_in_submodule(const char *submodule, const char *prefix,
1346 each_ref_fn fn, void *cb_data,
1347 unsigned int broken)
1348 {
1349 unsigned int flag = 0;
1350
1351 if (broken)
1352 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1353 return do_for_each_ref(get_submodule_ref_store(submodule),
1354 prefix, fn, 0, flag, cb_data);
1355 }
1356
1357 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1358 {
1359 return do_for_each_ref(get_main_ref_store(),
1360 git_replace_ref_base, fn,
1361 strlen(git_replace_ref_base),
1362 0, cb_data);
1363 }
1364
1365 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1366 {
1367 struct strbuf buf = STRBUF_INIT;
1368 int ret;
1369 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1370 ret = do_for_each_ref(get_main_ref_store(),
1371 buf.buf, fn, 0, 0, cb_data);
1372 strbuf_release(&buf);
1373 return ret;
1374 }
1375
1376 int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1377 {
1378 return do_for_each_ref(refs, "", fn, 0,
1379 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1380 }
1381
1382 int for_each_rawref(each_ref_fn fn, void *cb_data)
1383 {
1384 return refs_for_each_rawref(get_main_ref_store(), fn, cb_data);
1385 }
1386
1387 int refs_read_raw_ref(struct ref_store *ref_store,
1388 const char *refname, unsigned char *sha1,
1389 struct strbuf *referent, unsigned int *type)
1390 {
1391 return ref_store->be->read_raw_ref(ref_store, refname, sha1, referent, type);
1392 }
1393
1394 /* This function needs to return a meaningful errno on failure */
1395 const char *refs_resolve_ref_unsafe(struct ref_store *refs,
1396 const char *refname,
1397 int resolve_flags,
1398 unsigned char *sha1, int *flags)
1399 {
1400 static struct strbuf sb_refname = STRBUF_INIT;
1401 int unused_flags;
1402 int symref_count;
1403
1404 if (!flags)
1405 flags = &unused_flags;
1406
1407 *flags = 0;
1408
1409 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1410 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1411 !refname_is_safe(refname)) {
1412 errno = EINVAL;
1413 return NULL;
1414 }
1415
1416 /*
1417 * dwim_ref() uses REF_ISBROKEN to distinguish between
1418 * missing refs and refs that were present but invalid,
1419 * to complain about the latter to stderr.
1420 *
1421 * We don't know whether the ref exists, so don't set
1422 * REF_ISBROKEN yet.
1423 */
1424 *flags |= REF_BAD_NAME;
1425 }
1426
1427 for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1428 unsigned int read_flags = 0;
1429
1430 if (refs_read_raw_ref(refs, refname,
1431 sha1, &sb_refname, &read_flags)) {
1432 *flags |= read_flags;
1433 if (errno != ENOENT || (resolve_flags & RESOLVE_REF_READING))
1434 return NULL;
1435 hashclr(sha1);
1436 if (*flags & REF_BAD_NAME)
1437 *flags |= REF_ISBROKEN;
1438 return refname;
1439 }
1440
1441 *flags |= read_flags;
1442
1443 if (!(read_flags & REF_ISSYMREF)) {
1444 if (*flags & REF_BAD_NAME) {
1445 hashclr(sha1);
1446 *flags |= REF_ISBROKEN;
1447 }
1448 return refname;
1449 }
1450
1451 refname = sb_refname.buf;
1452 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1453 hashclr(sha1);
1454 return refname;
1455 }
1456 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1457 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1458 !refname_is_safe(refname)) {
1459 errno = EINVAL;
1460 return NULL;
1461 }
1462
1463 *flags |= REF_ISBROKEN | REF_BAD_NAME;
1464 }
1465 }
1466
1467 errno = ELOOP;
1468 return NULL;
1469 }
1470
1471 /* backend functions */
1472 int refs_init_db(struct strbuf *err)
1473 {
1474 struct ref_store *refs = get_main_ref_store();
1475
1476 return refs->be->init_db(refs, err);
1477 }
1478
1479 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1480 unsigned char *sha1, int *flags)
1481 {
1482 return refs_resolve_ref_unsafe(get_main_ref_store(), refname,
1483 resolve_flags, sha1, flags);
1484 }
1485
1486 int resolve_gitlink_ref(const char *submodule, const char *refname,
1487 unsigned char *sha1)
1488 {
1489 size_t len = strlen(submodule);
1490 struct ref_store *refs;
1491 int flags;
1492
1493 while (len && submodule[len - 1] == '/')
1494 len--;
1495
1496 if (!len)
1497 return -1;
1498
1499 if (submodule[len]) {
1500 /* We need to strip off one or more trailing slashes */
1501 char *stripped = xmemdupz(submodule, len);
1502
1503 refs = get_submodule_ref_store(stripped);
1504 free(stripped);
1505 } else {
1506 refs = get_submodule_ref_store(submodule);
1507 }
1508
1509 if (!refs)
1510 return -1;
1511
1512 if (!refs_resolve_ref_unsafe(refs, refname, 0, sha1, &flags) ||
1513 is_null_sha1(sha1))
1514 return -1;
1515 return 0;
1516 }
1517
1518 struct ref_store_hash_entry
1519 {
1520 struct hashmap_entry ent; /* must be the first member! */
1521
1522 struct ref_store *refs;
1523
1524 /* NUL-terminated identifier of the ref store: */
1525 char name[FLEX_ARRAY];
1526 };
1527
1528 static int ref_store_hash_cmp(const void *unused_cmp_data,
1529 const void *entry, const void *entry_or_key,
1530 const void *keydata)
1531 {
1532 const struct ref_store_hash_entry *e1 = entry, *e2 = entry_or_key;
1533 const char *name = keydata ? keydata : e2->name;
1534
1535 return strcmp(e1->name, name);
1536 }
1537
1538 static struct ref_store_hash_entry *alloc_ref_store_hash_entry(
1539 const char *name, struct ref_store *refs)
1540 {
1541 struct ref_store_hash_entry *entry;
1542
1543 FLEX_ALLOC_STR(entry, name, name);
1544 hashmap_entry_init(entry, strhash(name));
1545 entry->refs = refs;
1546 return entry;
1547 }
1548
1549 /* A pointer to the ref_store for the main repository: */
1550 static struct ref_store *main_ref_store;
1551
1552 /* A hashmap of ref_stores, stored by submodule name: */
1553 static struct hashmap submodule_ref_stores;
1554
1555 /* A hashmap of ref_stores, stored by worktree id: */
1556 static struct hashmap worktree_ref_stores;
1557
1558 /*
1559 * Look up a ref store by name. If that ref_store hasn't been
1560 * registered yet, return NULL.
1561 */
1562 static struct ref_store *lookup_ref_store_map(struct hashmap *map,
1563 const char *name)
1564 {
1565 struct ref_store_hash_entry *entry;
1566
1567 if (!map->tablesize)
1568 /* It's initialized on demand in register_ref_store(). */
1569 return NULL;
1570
1571 entry = hashmap_get_from_hash(map, strhash(name), name);
1572 return entry ? entry->refs : NULL;
1573 }
1574
1575 /*
1576 * Create, record, and return a ref_store instance for the specified
1577 * gitdir.
1578 */
1579 static struct ref_store *ref_store_init(const char *gitdir,
1580 unsigned int flags)
1581 {
1582 const char *be_name = "files";
1583 struct ref_storage_be *be = find_ref_storage_backend(be_name);
1584 struct ref_store *refs;
1585
1586 if (!be)
1587 die("BUG: reference backend %s is unknown", be_name);
1588
1589 refs = be->init(gitdir, flags);
1590 return refs;
1591 }
1592
1593 struct ref_store *get_main_ref_store(void)
1594 {
1595 if (main_ref_store)
1596 return main_ref_store;
1597
1598 main_ref_store = ref_store_init(get_git_dir(), REF_STORE_ALL_CAPS);
1599 return main_ref_store;
1600 }
1601
1602 /*
1603 * Associate a ref store with a name. It is a fatal error to call this
1604 * function twice for the same name.
1605 */
1606 static void register_ref_store_map(struct hashmap *map,
1607 const char *type,
1608 struct ref_store *refs,
1609 const char *name)
1610 {
1611 if (!map->tablesize)
1612 hashmap_init(map, ref_store_hash_cmp, NULL, 0);
1613
1614 if (hashmap_put(map, alloc_ref_store_hash_entry(name, refs)))
1615 die("BUG: %s ref_store '%s' initialized twice", type, name);
1616 }
1617
1618 struct ref_store *get_submodule_ref_store(const char *submodule)
1619 {
1620 struct strbuf submodule_sb = STRBUF_INIT;
1621 struct ref_store *refs;
1622 int ret;
1623
1624 if (!submodule || !*submodule) {
1625 /*
1626 * FIXME: This case is ideally not allowed. But that
1627 * can't happen until we clean up all the callers.
1628 */
1629 return get_main_ref_store();
1630 }
1631
1632 refs = lookup_ref_store_map(&submodule_ref_stores, submodule);
1633 if (refs)
1634 return refs;
1635
1636 strbuf_addstr(&submodule_sb, submodule);
1637 ret = is_nonbare_repository_dir(&submodule_sb);
1638 strbuf_release(&submodule_sb);
1639 if (!ret)
1640 return NULL;
1641
1642 ret = submodule_to_gitdir(&submodule_sb, submodule);
1643 if (ret) {
1644 strbuf_release(&submodule_sb);
1645 return NULL;
1646 }
1647
1648 /* assume that add_submodule_odb() has been called */
1649 refs = ref_store_init(submodule_sb.buf,
1650 REF_STORE_READ | REF_STORE_ODB);
1651 register_ref_store_map(&submodule_ref_stores, "submodule",
1652 refs, submodule);
1653
1654 strbuf_release(&submodule_sb);
1655 return refs;
1656 }
1657
1658 struct ref_store *get_worktree_ref_store(const struct worktree *wt)
1659 {
1660 struct ref_store *refs;
1661 const char *id;
1662
1663 if (wt->is_current)
1664 return get_main_ref_store();
1665
1666 id = wt->id ? wt->id : "/";
1667 refs = lookup_ref_store_map(&worktree_ref_stores, id);
1668 if (refs)
1669 return refs;
1670
1671 if (wt->id)
1672 refs = ref_store_init(git_common_path("worktrees/%s", wt->id),
1673 REF_STORE_ALL_CAPS);
1674 else
1675 refs = ref_store_init(get_git_common_dir(),
1676 REF_STORE_ALL_CAPS);
1677
1678 if (refs)
1679 register_ref_store_map(&worktree_ref_stores, "worktree",
1680 refs, id);
1681 return refs;
1682 }
1683
1684 void base_ref_store_init(struct ref_store *refs,
1685 const struct ref_storage_be *be)
1686 {
1687 refs->be = be;
1688 }
1689
1690 /* backend functions */
1691 int refs_pack_refs(struct ref_store *refs, unsigned int flags)
1692 {
1693 return refs->be->pack_refs(refs, flags);
1694 }
1695
1696 int refs_peel_ref(struct ref_store *refs, const char *refname,
1697 unsigned char *sha1)
1698 {
1699 return refs->be->peel_ref(refs, refname, sha1);
1700 }
1701
1702 int peel_ref(const char *refname, unsigned char *sha1)
1703 {
1704 return refs_peel_ref(get_main_ref_store(), refname, sha1);
1705 }
1706
1707 int refs_create_symref(struct ref_store *refs,
1708 const char *ref_target,
1709 const char *refs_heads_master,
1710 const char *logmsg)
1711 {
1712 return refs->be->create_symref(refs, ref_target,
1713 refs_heads_master,
1714 logmsg);
1715 }
1716
1717 int create_symref(const char *ref_target, const char *refs_heads_master,
1718 const char *logmsg)
1719 {
1720 return refs_create_symref(get_main_ref_store(), ref_target,
1721 refs_heads_master, logmsg);
1722 }
1723
1724 int ref_update_reject_duplicates(struct string_list *refnames,
1725 struct strbuf *err)
1726 {
1727 size_t i, n = refnames->nr;
1728
1729 assert(err);
1730
1731 for (i = 1; i < n; i++) {
1732 int cmp = strcmp(refnames->items[i - 1].string,
1733 refnames->items[i].string);
1734
1735 if (!cmp) {
1736 strbuf_addf(err,
1737 "multiple updates for ref '%s' not allowed.",
1738 refnames->items[i].string);
1739 return 1;
1740 } else if (cmp > 0) {
1741 die("BUG: ref_update_reject_duplicates() received unsorted list");
1742 }
1743 }
1744 return 0;
1745 }
1746
1747 int ref_transaction_prepare(struct ref_transaction *transaction,
1748 struct strbuf *err)
1749 {
1750 struct ref_store *refs = transaction->ref_store;
1751
1752 switch (transaction->state) {
1753 case REF_TRANSACTION_OPEN:
1754 /* Good. */
1755 break;
1756 case REF_TRANSACTION_PREPARED:
1757 die("BUG: prepare called twice on reference transaction");
1758 break;
1759 case REF_TRANSACTION_CLOSED:
1760 die("BUG: prepare called on a closed reference transaction");
1761 break;
1762 default:
1763 die("BUG: unexpected reference transaction state");
1764 break;
1765 }
1766
1767 if (getenv(GIT_QUARANTINE_ENVIRONMENT)) {
1768 strbuf_addstr(err,
1769 _("ref updates forbidden inside quarantine environment"));
1770 return -1;
1771 }
1772
1773 return refs->be->transaction_prepare(refs, transaction, err);
1774 }
1775
1776 int ref_transaction_abort(struct ref_transaction *transaction,
1777 struct strbuf *err)
1778 {
1779 struct ref_store *refs = transaction->ref_store;
1780 int ret = 0;
1781
1782 switch (transaction->state) {
1783 case REF_TRANSACTION_OPEN:
1784 /* No need to abort explicitly. */
1785 break;
1786 case REF_TRANSACTION_PREPARED:
1787 ret = refs->be->transaction_abort(refs, transaction, err);
1788 break;
1789 case REF_TRANSACTION_CLOSED:
1790 die("BUG: abort called on a closed reference transaction");
1791 break;
1792 default:
1793 die("BUG: unexpected reference transaction state");
1794 break;
1795 }
1796
1797 ref_transaction_free(transaction);
1798 return ret;
1799 }
1800
1801 int ref_transaction_commit(struct ref_transaction *transaction,
1802 struct strbuf *err)
1803 {
1804 struct ref_store *refs = transaction->ref_store;
1805 int ret;
1806
1807 switch (transaction->state) {
1808 case REF_TRANSACTION_OPEN:
1809 /* Need to prepare first. */
1810 ret = ref_transaction_prepare(transaction, err);
1811 if (ret)
1812 return ret;
1813 break;
1814 case REF_TRANSACTION_PREPARED:
1815 /* Fall through to finish. */
1816 break;
1817 case REF_TRANSACTION_CLOSED:
1818 die("BUG: commit called on a closed reference transaction");
1819 break;
1820 default:
1821 die("BUG: unexpected reference transaction state");
1822 break;
1823 }
1824
1825 return refs->be->transaction_finish(refs, transaction, err);
1826 }
1827
1828 int refs_verify_refname_available(struct ref_store *refs,
1829 const char *refname,
1830 const struct string_list *extras,
1831 const struct string_list *skip,
1832 struct strbuf *err)
1833 {
1834 const char *slash;
1835 const char *extra_refname;
1836 struct strbuf dirname = STRBUF_INIT;
1837 struct strbuf referent = STRBUF_INIT;
1838 struct object_id oid;
1839 unsigned int type;
1840 struct ref_iterator *iter;
1841 int ok;
1842 int ret = -1;
1843
1844 /*
1845 * For the sake of comments in this function, suppose that
1846 * refname is "refs/foo/bar".
1847 */
1848
1849 assert(err);
1850
1851 strbuf_grow(&dirname, strlen(refname) + 1);
1852 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
1853 /* Expand dirname to the new prefix, not including the trailing slash: */
1854 strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
1855
1856 /*
1857 * We are still at a leading dir of the refname (e.g.,
1858 * "refs/foo"; if there is a reference with that name,
1859 * it is a conflict, *unless* it is in skip.
1860 */
1861 if (skip && string_list_has_string(skip, dirname.buf))
1862 continue;
1863
1864 if (!refs_read_raw_ref(refs, dirname.buf, oid.hash, &referent, &type)) {
1865 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1866 dirname.buf, refname);
1867 goto cleanup;
1868 }
1869
1870 if (extras && string_list_has_string(extras, dirname.buf)) {
1871 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1872 refname, dirname.buf);
1873 goto cleanup;
1874 }
1875 }
1876
1877 /*
1878 * We are at the leaf of our refname (e.g., "refs/foo/bar").
1879 * There is no point in searching for a reference with that
1880 * name, because a refname isn't considered to conflict with
1881 * itself. But we still need to check for references whose
1882 * names are in the "refs/foo/bar/" namespace, because they
1883 * *do* conflict.
1884 */
1885 strbuf_addstr(&dirname, refname + dirname.len);
1886 strbuf_addch(&dirname, '/');
1887
1888 iter = refs_ref_iterator_begin(refs, dirname.buf, 0,
1889 DO_FOR_EACH_INCLUDE_BROKEN);
1890 while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
1891 if (skip &&
1892 string_list_has_string(skip, iter->refname))
1893 continue;
1894
1895 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1896 iter->refname, refname);
1897 ref_iterator_abort(iter);
1898 goto cleanup;
1899 }
1900
1901 if (ok != ITER_DONE)
1902 die("BUG: error while iterating over references");
1903
1904 extra_refname = find_descendant_ref(dirname.buf, extras, skip);
1905 if (extra_refname)
1906 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1907 refname, extra_refname);
1908 else
1909 ret = 0;
1910
1911 cleanup:
1912 strbuf_release(&referent);
1913 strbuf_release(&dirname);
1914 return ret;
1915 }
1916
1917 int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1918 {
1919 struct ref_iterator *iter;
1920
1921 iter = refs->be->reflog_iterator_begin(refs);
1922
1923 return do_for_each_ref_iterator(iter, fn, cb_data);
1924 }
1925
1926 int for_each_reflog(each_ref_fn fn, void *cb_data)
1927 {
1928 return refs_for_each_reflog(get_main_ref_store(), fn, cb_data);
1929 }
1930
1931 int refs_for_each_reflog_ent_reverse(struct ref_store *refs,
1932 const char *refname,
1933 each_reflog_ent_fn fn,
1934 void *cb_data)
1935 {
1936 return refs->be->for_each_reflog_ent_reverse(refs, refname,
1937 fn, cb_data);
1938 }
1939
1940 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
1941 void *cb_data)
1942 {
1943 return refs_for_each_reflog_ent_reverse(get_main_ref_store(),
1944 refname, fn, cb_data);
1945 }
1946
1947 int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname,
1948 each_reflog_ent_fn fn, void *cb_data)
1949 {
1950 return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
1951 }
1952
1953 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
1954 void *cb_data)
1955 {
1956 return refs_for_each_reflog_ent(get_main_ref_store(), refname,
1957 fn, cb_data);
1958 }
1959
1960 int refs_reflog_exists(struct ref_store *refs, const char *refname)
1961 {
1962 return refs->be->reflog_exists(refs, refname);
1963 }
1964
1965 int reflog_exists(const char *refname)
1966 {
1967 return refs_reflog_exists(get_main_ref_store(), refname);
1968 }
1969
1970 int refs_create_reflog(struct ref_store *refs, const char *refname,
1971 int force_create, struct strbuf *err)
1972 {
1973 return refs->be->create_reflog(refs, refname, force_create, err);
1974 }
1975
1976 int safe_create_reflog(const char *refname, int force_create,
1977 struct strbuf *err)
1978 {
1979 return refs_create_reflog(get_main_ref_store(), refname,
1980 force_create, err);
1981 }
1982
1983 int refs_delete_reflog(struct ref_store *refs, const char *refname)
1984 {
1985 return refs->be->delete_reflog(refs, refname);
1986 }
1987
1988 int delete_reflog(const char *refname)
1989 {
1990 return refs_delete_reflog(get_main_ref_store(), refname);
1991 }
1992
1993 int refs_reflog_expire(struct ref_store *refs,
1994 const char *refname, const unsigned char *sha1,
1995 unsigned int flags,
1996 reflog_expiry_prepare_fn prepare_fn,
1997 reflog_expiry_should_prune_fn should_prune_fn,
1998 reflog_expiry_cleanup_fn cleanup_fn,
1999 void *policy_cb_data)
2000 {
2001 return refs->be->reflog_expire(refs, refname, sha1, flags,
2002 prepare_fn, should_prune_fn,
2003 cleanup_fn, policy_cb_data);
2004 }
2005
2006 int reflog_expire(const char *refname, const unsigned char *sha1,
2007 unsigned int flags,
2008 reflog_expiry_prepare_fn prepare_fn,
2009 reflog_expiry_should_prune_fn should_prune_fn,
2010 reflog_expiry_cleanup_fn cleanup_fn,
2011 void *policy_cb_data)
2012 {
2013 return refs_reflog_expire(get_main_ref_store(),
2014 refname, sha1, flags,
2015 prepare_fn, should_prune_fn,
2016 cleanup_fn, policy_cb_data);
2017 }
2018
2019 int initial_ref_transaction_commit(struct ref_transaction *transaction,
2020 struct strbuf *err)
2021 {
2022 struct ref_store *refs = transaction->ref_store;
2023
2024 return refs->be->initial_transaction_commit(refs, transaction, err);
2025 }
2026
2027 int refs_delete_refs(struct ref_store *refs, const char *msg,
2028 struct string_list *refnames, unsigned int flags)
2029 {
2030 return refs->be->delete_refs(refs, msg, refnames, flags);
2031 }
2032
2033 int delete_refs(const char *msg, struct string_list *refnames,
2034 unsigned int flags)
2035 {
2036 return refs_delete_refs(get_main_ref_store(), msg, refnames, flags);
2037 }
2038
2039 int refs_rename_ref(struct ref_store *refs, const char *oldref,
2040 const char *newref, const char *logmsg)
2041 {
2042 return refs->be->rename_ref(refs, oldref, newref, logmsg);
2043 }
2044
2045 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
2046 {
2047 return refs_rename_ref(get_main_ref_store(), oldref, newref, logmsg);
2048 }