Merge branch 'jt/partial-clone-fsck-connectivity'
[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-store.h"
13 #include "object.h"
14 #include "tag.h"
15 #include "submodule.h"
16 #include "worktree.h"
17 #include "argv-array.h"
18 #include "repository.h"
19
20 /*
21 * List of all available backends
22 */
23 static struct ref_storage_be *refs_backends = &refs_be_files;
24
25 static struct ref_storage_be *find_ref_storage_backend(const char *name)
26 {
27 struct ref_storage_be *be;
28 for (be = refs_backends; be; be = be->next)
29 if (!strcmp(be->name, name))
30 return be;
31 return NULL;
32 }
33
34 int ref_storage_backend_exists(const char *name)
35 {
36 return find_ref_storage_backend(name) != NULL;
37 }
38
39 /*
40 * How to handle various characters in refnames:
41 * 0: An acceptable character for refs
42 * 1: End-of-component
43 * 2: ., look for a preceding . to reject .. in refs
44 * 3: {, look for a preceding @ to reject @{ in refs
45 * 4: A bad character: ASCII control characters, and
46 * ":", "?", "[", "\", "^", "~", SP, or TAB
47 * 5: *, reject unless REFNAME_REFSPEC_PATTERN is set
48 */
49 static unsigned char refname_disposition[256] = {
50 1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
51 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
52 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 2, 1,
53 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4,
54 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
55 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 4, 0,
56 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
57 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 4
58 };
59
60 /*
61 * Try to read one refname component from the front of refname.
62 * Return the length of the component found, or -1 if the component is
63 * not legal. It is legal if it is something reasonable to have under
64 * ".git/refs/"; We do not like it if:
65 *
66 * - any path component of it begins with ".", or
67 * - it has double dots "..", or
68 * - it has ASCII control characters, or
69 * - it has ":", "?", "[", "\", "^", "~", SP, or TAB anywhere, or
70 * - it has "*" anywhere unless REFNAME_REFSPEC_PATTERN is set, or
71 * - it ends with a "/", or
72 * - it ends with ".lock", or
73 * - it contains a "@{" portion
74 */
75 static int check_refname_component(const char *refname, int *flags)
76 {
77 const char *cp;
78 char last = '\0';
79
80 for (cp = refname; ; cp++) {
81 int ch = *cp & 255;
82 unsigned char disp = refname_disposition[ch];
83 switch (disp) {
84 case 1:
85 goto out;
86 case 2:
87 if (last == '.')
88 return -1; /* Refname contains "..". */
89 break;
90 case 3:
91 if (last == '@')
92 return -1; /* Refname contains "@{". */
93 break;
94 case 4:
95 return -1;
96 case 5:
97 if (!(*flags & REFNAME_REFSPEC_PATTERN))
98 return -1; /* refspec can't be a pattern */
99
100 /*
101 * Unset the pattern flag so that we only accept
102 * a single asterisk for one side of refspec.
103 */
104 *flags &= ~ REFNAME_REFSPEC_PATTERN;
105 break;
106 }
107 last = ch;
108 }
109 out:
110 if (cp == refname)
111 return 0; /* Component has zero length. */
112 if (refname[0] == '.')
113 return -1; /* Component starts with '.'. */
114 if (cp - refname >= LOCK_SUFFIX_LEN &&
115 !memcmp(cp - LOCK_SUFFIX_LEN, LOCK_SUFFIX, LOCK_SUFFIX_LEN))
116 return -1; /* Refname ends with ".lock". */
117 return cp - refname;
118 }
119
120 int check_refname_format(const char *refname, int flags)
121 {
122 int component_len, component_count = 0;
123
124 if (!strcmp(refname, "@"))
125 /* Refname is a single character '@'. */
126 return -1;
127
128 while (1) {
129 /* We are at the start of a path component. */
130 component_len = check_refname_component(refname, &flags);
131 if (component_len <= 0)
132 return -1;
133
134 component_count++;
135 if (refname[component_len] == '\0')
136 break;
137 /* Skip to next component. */
138 refname += component_len + 1;
139 }
140
141 if (refname[component_len - 1] == '.')
142 return -1; /* Refname ends with '.'. */
143 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
144 return -1; /* Refname has only one component. */
145 return 0;
146 }
147
148 int refname_is_safe(const char *refname)
149 {
150 const char *rest;
151
152 if (skip_prefix(refname, "refs/", &rest)) {
153 char *buf;
154 int result;
155 size_t restlen = strlen(rest);
156
157 /* rest must not be empty, or start or end with "/" */
158 if (!restlen || *rest == '/' || rest[restlen - 1] == '/')
159 return 0;
160
161 /*
162 * Does the refname try to escape refs/?
163 * For example: refs/foo/../bar is safe but refs/foo/../../bar
164 * is not.
165 */
166 buf = xmallocz(restlen);
167 result = !normalize_path_copy(buf, rest) && !strcmp(buf, rest);
168 free(buf);
169 return result;
170 }
171
172 do {
173 if (!isupper(*refname) && *refname != '_')
174 return 0;
175 refname++;
176 } while (*refname);
177 return 1;
178 }
179
180 /*
181 * Return true if refname, which has the specified oid and flags, can
182 * be resolved to an object in the database. If the referred-to object
183 * does not exist, emit a warning and return false.
184 */
185 int ref_resolves_to_object(const char *refname,
186 const struct object_id *oid,
187 unsigned int flags)
188 {
189 if (flags & REF_ISBROKEN)
190 return 0;
191 if (!has_sha1_file(oid->hash)) {
192 error("%s does not point to a valid object!", refname);
193 return 0;
194 }
195 return 1;
196 }
197
198 char *refs_resolve_refdup(struct ref_store *refs,
199 const char *refname, int resolve_flags,
200 struct object_id *oid, int *flags)
201 {
202 const char *result;
203
204 result = refs_resolve_ref_unsafe(refs, refname, resolve_flags,
205 oid, flags);
206 return xstrdup_or_null(result);
207 }
208
209 char *resolve_refdup(const char *refname, int resolve_flags,
210 struct object_id *oid, int *flags)
211 {
212 return refs_resolve_refdup(get_main_ref_store(the_repository),
213 refname, resolve_flags,
214 oid, flags);
215 }
216
217 /* The argument to filter_refs */
218 struct ref_filter {
219 const char *pattern;
220 each_ref_fn *fn;
221 void *cb_data;
222 };
223
224 int refs_read_ref_full(struct ref_store *refs, const char *refname,
225 int resolve_flags, struct object_id *oid, int *flags)
226 {
227 if (refs_resolve_ref_unsafe(refs, refname, resolve_flags, oid, flags))
228 return 0;
229 return -1;
230 }
231
232 int read_ref_full(const char *refname, int resolve_flags, struct object_id *oid, int *flags)
233 {
234 return refs_read_ref_full(get_main_ref_store(the_repository), refname,
235 resolve_flags, oid, flags);
236 }
237
238 int read_ref(const char *refname, struct object_id *oid)
239 {
240 return read_ref_full(refname, RESOLVE_REF_READING, oid, NULL);
241 }
242
243 int ref_exists(const char *refname)
244 {
245 return !!resolve_ref_unsafe(refname, RESOLVE_REF_READING, NULL, NULL);
246 }
247
248 static int match_ref_pattern(const char *refname,
249 const struct string_list_item *item)
250 {
251 int matched = 0;
252 if (item->util == NULL) {
253 if (!wildmatch(item->string, refname, 0))
254 matched = 1;
255 } else {
256 const char *rest;
257 if (skip_prefix(refname, item->string, &rest) &&
258 (!*rest || *rest == '/'))
259 matched = 1;
260 }
261 return matched;
262 }
263
264 int ref_filter_match(const char *refname,
265 const struct string_list *include_patterns,
266 const struct string_list *exclude_patterns)
267 {
268 struct string_list_item *item;
269
270 if (exclude_patterns && exclude_patterns->nr) {
271 for_each_string_list_item(item, exclude_patterns) {
272 if (match_ref_pattern(refname, item))
273 return 0;
274 }
275 }
276
277 if (include_patterns && include_patterns->nr) {
278 int found = 0;
279 for_each_string_list_item(item, include_patterns) {
280 if (match_ref_pattern(refname, item)) {
281 found = 1;
282 break;
283 }
284 }
285
286 if (!found)
287 return 0;
288 }
289 return 1;
290 }
291
292 static int filter_refs(const char *refname, const struct object_id *oid,
293 int flags, void *data)
294 {
295 struct ref_filter *filter = (struct ref_filter *)data;
296
297 if (wildmatch(filter->pattern, refname, 0))
298 return 0;
299 return filter->fn(refname, oid, flags, filter->cb_data);
300 }
301
302 enum peel_status peel_object(const struct object_id *name, struct object_id *oid)
303 {
304 struct object *o = lookup_unknown_object(name->hash);
305
306 if (o->type == OBJ_NONE) {
307 int type = oid_object_info(the_repository, name, NULL);
308 if (type < 0 || !object_as_type(o, type, 0))
309 return PEEL_INVALID;
310 }
311
312 if (o->type != OBJ_TAG)
313 return PEEL_NON_TAG;
314
315 o = deref_tag_noverify(o);
316 if (!o)
317 return PEEL_INVALID;
318
319 oidcpy(oid, &o->oid);
320 return PEEL_PEELED;
321 }
322
323 struct warn_if_dangling_data {
324 FILE *fp;
325 const char *refname;
326 const struct string_list *refnames;
327 const char *msg_fmt;
328 };
329
330 static int warn_if_dangling_symref(const char *refname, const struct object_id *oid,
331 int flags, void *cb_data)
332 {
333 struct warn_if_dangling_data *d = cb_data;
334 const char *resolves_to;
335
336 if (!(flags & REF_ISSYMREF))
337 return 0;
338
339 resolves_to = resolve_ref_unsafe(refname, 0, NULL, NULL);
340 if (!resolves_to
341 || (d->refname
342 ? strcmp(resolves_to, d->refname)
343 : !string_list_has_string(d->refnames, resolves_to))) {
344 return 0;
345 }
346
347 fprintf(d->fp, d->msg_fmt, refname);
348 fputc('\n', d->fp);
349 return 0;
350 }
351
352 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
353 {
354 struct warn_if_dangling_data data;
355
356 data.fp = fp;
357 data.refname = refname;
358 data.refnames = NULL;
359 data.msg_fmt = msg_fmt;
360 for_each_rawref(warn_if_dangling_symref, &data);
361 }
362
363 void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames)
364 {
365 struct warn_if_dangling_data data;
366
367 data.fp = fp;
368 data.refname = NULL;
369 data.refnames = refnames;
370 data.msg_fmt = msg_fmt;
371 for_each_rawref(warn_if_dangling_symref, &data);
372 }
373
374 int refs_for_each_tag_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
375 {
376 return refs_for_each_ref_in(refs, "refs/tags/", fn, cb_data);
377 }
378
379 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
380 {
381 return refs_for_each_tag_ref(get_main_ref_store(the_repository), fn, cb_data);
382 }
383
384 int refs_for_each_branch_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
385 {
386 return refs_for_each_ref_in(refs, "refs/heads/", fn, cb_data);
387 }
388
389 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
390 {
391 return refs_for_each_branch_ref(get_main_ref_store(the_repository), fn, cb_data);
392 }
393
394 int refs_for_each_remote_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
395 {
396 return refs_for_each_ref_in(refs, "refs/remotes/", fn, cb_data);
397 }
398
399 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
400 {
401 return refs_for_each_remote_ref(get_main_ref_store(the_repository), fn, cb_data);
402 }
403
404 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
405 {
406 struct strbuf buf = STRBUF_INIT;
407 int ret = 0;
408 struct object_id oid;
409 int flag;
410
411 strbuf_addf(&buf, "%sHEAD", get_git_namespace());
412 if (!read_ref_full(buf.buf, RESOLVE_REF_READING, &oid, &flag))
413 ret = fn(buf.buf, &oid, flag, cb_data);
414 strbuf_release(&buf);
415
416 return ret;
417 }
418
419 void normalize_glob_ref(struct string_list_item *item, const char *prefix,
420 const char *pattern)
421 {
422 struct strbuf normalized_pattern = STRBUF_INIT;
423
424 if (*pattern == '/')
425 BUG("pattern must not start with '/'");
426
427 if (prefix) {
428 strbuf_addstr(&normalized_pattern, prefix);
429 }
430 else if (!starts_with(pattern, "refs/"))
431 strbuf_addstr(&normalized_pattern, "refs/");
432 strbuf_addstr(&normalized_pattern, pattern);
433 strbuf_strip_suffix(&normalized_pattern, "/");
434
435 item->string = strbuf_detach(&normalized_pattern, NULL);
436 item->util = has_glob_specials(pattern) ? NULL : item->string;
437 strbuf_release(&normalized_pattern);
438 }
439
440 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
441 const char *prefix, void *cb_data)
442 {
443 struct strbuf real_pattern = STRBUF_INIT;
444 struct ref_filter filter;
445 int ret;
446
447 if (!prefix && !starts_with(pattern, "refs/"))
448 strbuf_addstr(&real_pattern, "refs/");
449 else if (prefix)
450 strbuf_addstr(&real_pattern, prefix);
451 strbuf_addstr(&real_pattern, pattern);
452
453 if (!has_glob_specials(pattern)) {
454 /* Append implied '/' '*' if not present. */
455 strbuf_complete(&real_pattern, '/');
456 /* No need to check for '*', there is none. */
457 strbuf_addch(&real_pattern, '*');
458 }
459
460 filter.pattern = real_pattern.buf;
461 filter.fn = fn;
462 filter.cb_data = cb_data;
463 ret = for_each_ref(filter_refs, &filter);
464
465 strbuf_release(&real_pattern);
466 return ret;
467 }
468
469 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
470 {
471 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
472 }
473
474 const char *prettify_refname(const char *name)
475 {
476 if (skip_prefix(name, "refs/heads/", &name) ||
477 skip_prefix(name, "refs/tags/", &name) ||
478 skip_prefix(name, "refs/remotes/", &name))
479 ; /* nothing */
480 return name;
481 }
482
483 static const char *ref_rev_parse_rules[] = {
484 "%.*s",
485 "refs/%.*s",
486 "refs/tags/%.*s",
487 "refs/heads/%.*s",
488 "refs/remotes/%.*s",
489 "refs/remotes/%.*s/HEAD",
490 NULL
491 };
492
493 int refname_match(const char *abbrev_name, const char *full_name)
494 {
495 const char **p;
496 const int abbrev_name_len = strlen(abbrev_name);
497
498 for (p = ref_rev_parse_rules; *p; p++) {
499 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
500 return 1;
501 }
502 }
503
504 return 0;
505 }
506
507 /*
508 * Given a 'prefix' expand it by the rules in 'ref_rev_parse_rules' and add
509 * the results to 'prefixes'
510 */
511 void expand_ref_prefix(struct argv_array *prefixes, const char *prefix)
512 {
513 const char **p;
514 int len = strlen(prefix);
515
516 for (p = ref_rev_parse_rules; *p; p++)
517 argv_array_pushf(prefixes, *p, len, prefix);
518 }
519
520 /*
521 * *string and *len will only be substituted, and *string returned (for
522 * later free()ing) if the string passed in is a magic short-hand form
523 * to name a branch.
524 */
525 static char *substitute_branch_name(const char **string, int *len)
526 {
527 struct strbuf buf = STRBUF_INIT;
528 int ret = interpret_branch_name(*string, *len, &buf, 0);
529
530 if (ret == *len) {
531 size_t size;
532 *string = strbuf_detach(&buf, &size);
533 *len = size;
534 return (char *)*string;
535 }
536
537 return NULL;
538 }
539
540 int dwim_ref(const char *str, int len, struct object_id *oid, char **ref)
541 {
542 char *last_branch = substitute_branch_name(&str, &len);
543 int refs_found = expand_ref(str, len, oid, ref);
544 free(last_branch);
545 return refs_found;
546 }
547
548 int expand_ref(const char *str, int len, struct object_id *oid, char **ref)
549 {
550 const char **p, *r;
551 int refs_found = 0;
552 struct strbuf fullref = STRBUF_INIT;
553
554 *ref = NULL;
555 for (p = ref_rev_parse_rules; *p; p++) {
556 struct object_id oid_from_ref;
557 struct object_id *this_result;
558 int flag;
559
560 this_result = refs_found ? &oid_from_ref : oid;
561 strbuf_reset(&fullref);
562 strbuf_addf(&fullref, *p, len, str);
563 r = resolve_ref_unsafe(fullref.buf, RESOLVE_REF_READING,
564 this_result, &flag);
565 if (r) {
566 if (!refs_found++)
567 *ref = xstrdup(r);
568 if (!warn_ambiguous_refs)
569 break;
570 } else if ((flag & REF_ISSYMREF) && strcmp(fullref.buf, "HEAD")) {
571 warning("ignoring dangling symref %s.", fullref.buf);
572 } else if ((flag & REF_ISBROKEN) && strchr(fullref.buf, '/')) {
573 warning("ignoring broken ref %s.", fullref.buf);
574 }
575 }
576 strbuf_release(&fullref);
577 return refs_found;
578 }
579
580 int dwim_log(const char *str, int len, struct object_id *oid, char **log)
581 {
582 char *last_branch = substitute_branch_name(&str, &len);
583 const char **p;
584 int logs_found = 0;
585 struct strbuf path = STRBUF_INIT;
586
587 *log = NULL;
588 for (p = ref_rev_parse_rules; *p; p++) {
589 struct object_id hash;
590 const char *ref, *it;
591
592 strbuf_reset(&path);
593 strbuf_addf(&path, *p, len, str);
594 ref = resolve_ref_unsafe(path.buf, RESOLVE_REF_READING,
595 &hash, NULL);
596 if (!ref)
597 continue;
598 if (reflog_exists(path.buf))
599 it = path.buf;
600 else if (strcmp(ref, path.buf) && reflog_exists(ref))
601 it = ref;
602 else
603 continue;
604 if (!logs_found++) {
605 *log = xstrdup(it);
606 oidcpy(oid, &hash);
607 }
608 if (!warn_ambiguous_refs)
609 break;
610 }
611 strbuf_release(&path);
612 free(last_branch);
613 return logs_found;
614 }
615
616 static int is_per_worktree_ref(const char *refname)
617 {
618 return !strcmp(refname, "HEAD") ||
619 starts_with(refname, "refs/bisect/") ||
620 starts_with(refname, "refs/rewritten/");
621 }
622
623 static int is_pseudoref_syntax(const char *refname)
624 {
625 const char *c;
626
627 for (c = refname; *c; c++) {
628 if (!isupper(*c) && *c != '-' && *c != '_')
629 return 0;
630 }
631
632 return 1;
633 }
634
635 enum ref_type ref_type(const char *refname)
636 {
637 if (is_per_worktree_ref(refname))
638 return REF_TYPE_PER_WORKTREE;
639 if (is_pseudoref_syntax(refname))
640 return REF_TYPE_PSEUDOREF;
641 return REF_TYPE_NORMAL;
642 }
643
644 long get_files_ref_lock_timeout_ms(void)
645 {
646 static int configured = 0;
647
648 /* The default timeout is 100 ms: */
649 static int timeout_ms = 100;
650
651 if (!configured) {
652 git_config_get_int("core.filesreflocktimeout", &timeout_ms);
653 configured = 1;
654 }
655
656 return timeout_ms;
657 }
658
659 static int write_pseudoref(const char *pseudoref, const struct object_id *oid,
660 const struct object_id *old_oid, struct strbuf *err)
661 {
662 const char *filename;
663 int fd;
664 struct lock_file lock = LOCK_INIT;
665 struct strbuf buf = STRBUF_INIT;
666 int ret = -1;
667
668 if (!oid)
669 return 0;
670
671 strbuf_addf(&buf, "%s\n", oid_to_hex(oid));
672
673 filename = git_path("%s", pseudoref);
674 fd = hold_lock_file_for_update_timeout(&lock, filename, 0,
675 get_files_ref_lock_timeout_ms());
676 if (fd < 0) {
677 strbuf_addf(err, "could not open '%s' for writing: %s",
678 filename, strerror(errno));
679 goto done;
680 }
681
682 if (old_oid) {
683 struct object_id actual_old_oid;
684
685 if (read_ref(pseudoref, &actual_old_oid)) {
686 if (!is_null_oid(old_oid)) {
687 strbuf_addf(err, "could not read ref '%s'",
688 pseudoref);
689 rollback_lock_file(&lock);
690 goto done;
691 }
692 } else if (is_null_oid(old_oid)) {
693 strbuf_addf(err, "ref '%s' already exists",
694 pseudoref);
695 rollback_lock_file(&lock);
696 goto done;
697 } else if (oidcmp(&actual_old_oid, old_oid)) {
698 strbuf_addf(err, "unexpected object ID when writing '%s'",
699 pseudoref);
700 rollback_lock_file(&lock);
701 goto done;
702 }
703 }
704
705 if (write_in_full(fd, buf.buf, buf.len) < 0) {
706 strbuf_addf(err, "could not write to '%s'", filename);
707 rollback_lock_file(&lock);
708 goto done;
709 }
710
711 commit_lock_file(&lock);
712 ret = 0;
713 done:
714 strbuf_release(&buf);
715 return ret;
716 }
717
718 static int delete_pseudoref(const char *pseudoref, const struct object_id *old_oid)
719 {
720 const char *filename;
721
722 filename = git_path("%s", pseudoref);
723
724 if (old_oid && !is_null_oid(old_oid)) {
725 struct lock_file lock = LOCK_INIT;
726 int fd;
727 struct object_id actual_old_oid;
728
729 fd = hold_lock_file_for_update_timeout(
730 &lock, filename, 0,
731 get_files_ref_lock_timeout_ms());
732 if (fd < 0) {
733 error_errno(_("could not open '%s' for writing"),
734 filename);
735 return -1;
736 }
737 if (read_ref(pseudoref, &actual_old_oid))
738 die("could not read ref '%s'", pseudoref);
739 if (oidcmp(&actual_old_oid, old_oid)) {
740 error("unexpected object ID when deleting '%s'",
741 pseudoref);
742 rollback_lock_file(&lock);
743 return -1;
744 }
745
746 unlink(filename);
747 rollback_lock_file(&lock);
748 } else {
749 unlink(filename);
750 }
751
752 return 0;
753 }
754
755 int refs_delete_ref(struct ref_store *refs, const char *msg,
756 const char *refname,
757 const struct object_id *old_oid,
758 unsigned int flags)
759 {
760 struct ref_transaction *transaction;
761 struct strbuf err = STRBUF_INIT;
762
763 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
764 assert(refs == get_main_ref_store(the_repository));
765 return delete_pseudoref(refname, old_oid);
766 }
767
768 transaction = ref_store_transaction_begin(refs, &err);
769 if (!transaction ||
770 ref_transaction_delete(transaction, refname, old_oid,
771 flags, msg, &err) ||
772 ref_transaction_commit(transaction, &err)) {
773 error("%s", err.buf);
774 ref_transaction_free(transaction);
775 strbuf_release(&err);
776 return 1;
777 }
778 ref_transaction_free(transaction);
779 strbuf_release(&err);
780 return 0;
781 }
782
783 int delete_ref(const char *msg, const char *refname,
784 const struct object_id *old_oid, unsigned int flags)
785 {
786 return refs_delete_ref(get_main_ref_store(the_repository), msg, refname,
787 old_oid, flags);
788 }
789
790 int copy_reflog_msg(char *buf, const char *msg)
791 {
792 char *cp = buf;
793 char c;
794 int wasspace = 1;
795
796 *cp++ = '\t';
797 while ((c = *msg++)) {
798 if (wasspace && isspace(c))
799 continue;
800 wasspace = isspace(c);
801 if (wasspace)
802 c = ' ';
803 *cp++ = c;
804 }
805 while (buf < cp && isspace(cp[-1]))
806 cp--;
807 *cp++ = '\n';
808 return cp - buf;
809 }
810
811 int should_autocreate_reflog(const char *refname)
812 {
813 switch (log_all_ref_updates) {
814 case LOG_REFS_ALWAYS:
815 return 1;
816 case LOG_REFS_NORMAL:
817 return starts_with(refname, "refs/heads/") ||
818 starts_with(refname, "refs/remotes/") ||
819 starts_with(refname, "refs/notes/") ||
820 !strcmp(refname, "HEAD");
821 default:
822 return 0;
823 }
824 }
825
826 int is_branch(const char *refname)
827 {
828 return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
829 }
830
831 struct read_ref_at_cb {
832 const char *refname;
833 timestamp_t at_time;
834 int cnt;
835 int reccnt;
836 struct object_id *oid;
837 int found_it;
838
839 struct object_id ooid;
840 struct object_id noid;
841 int tz;
842 timestamp_t date;
843 char **msg;
844 timestamp_t *cutoff_time;
845 int *cutoff_tz;
846 int *cutoff_cnt;
847 };
848
849 static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
850 const char *email, timestamp_t timestamp, int tz,
851 const char *message, void *cb_data)
852 {
853 struct read_ref_at_cb *cb = cb_data;
854
855 cb->reccnt++;
856 cb->tz = tz;
857 cb->date = timestamp;
858
859 if (timestamp <= cb->at_time || cb->cnt == 0) {
860 if (cb->msg)
861 *cb->msg = xstrdup(message);
862 if (cb->cutoff_time)
863 *cb->cutoff_time = timestamp;
864 if (cb->cutoff_tz)
865 *cb->cutoff_tz = tz;
866 if (cb->cutoff_cnt)
867 *cb->cutoff_cnt = cb->reccnt - 1;
868 /*
869 * we have not yet updated cb->[n|o]oid so they still
870 * hold the values for the previous record.
871 */
872 if (!is_null_oid(&cb->ooid)) {
873 oidcpy(cb->oid, noid);
874 if (oidcmp(&cb->ooid, noid))
875 warning("Log for ref %s has gap after %s.",
876 cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
877 }
878 else if (cb->date == cb->at_time)
879 oidcpy(cb->oid, noid);
880 else if (oidcmp(noid, cb->oid))
881 warning("Log for ref %s unexpectedly ended on %s.",
882 cb->refname, show_date(cb->date, cb->tz,
883 DATE_MODE(RFC2822)));
884 oidcpy(&cb->ooid, ooid);
885 oidcpy(&cb->noid, noid);
886 cb->found_it = 1;
887 return 1;
888 }
889 oidcpy(&cb->ooid, ooid);
890 oidcpy(&cb->noid, noid);
891 if (cb->cnt > 0)
892 cb->cnt--;
893 return 0;
894 }
895
896 static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
897 const char *email, timestamp_t timestamp,
898 int tz, const char *message, void *cb_data)
899 {
900 struct read_ref_at_cb *cb = cb_data;
901
902 if (cb->msg)
903 *cb->msg = xstrdup(message);
904 if (cb->cutoff_time)
905 *cb->cutoff_time = timestamp;
906 if (cb->cutoff_tz)
907 *cb->cutoff_tz = tz;
908 if (cb->cutoff_cnt)
909 *cb->cutoff_cnt = cb->reccnt;
910 oidcpy(cb->oid, ooid);
911 if (is_null_oid(cb->oid))
912 oidcpy(cb->oid, noid);
913 /* We just want the first entry */
914 return 1;
915 }
916
917 int read_ref_at(const char *refname, unsigned int flags, timestamp_t at_time, int cnt,
918 struct object_id *oid, char **msg,
919 timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
920 {
921 struct read_ref_at_cb cb;
922
923 memset(&cb, 0, sizeof(cb));
924 cb.refname = refname;
925 cb.at_time = at_time;
926 cb.cnt = cnt;
927 cb.msg = msg;
928 cb.cutoff_time = cutoff_time;
929 cb.cutoff_tz = cutoff_tz;
930 cb.cutoff_cnt = cutoff_cnt;
931 cb.oid = oid;
932
933 for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
934
935 if (!cb.reccnt) {
936 if (flags & GET_OID_QUIETLY)
937 exit(128);
938 else
939 die("Log for %s is empty.", refname);
940 }
941 if (cb.found_it)
942 return 0;
943
944 for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
945
946 return 1;
947 }
948
949 struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs,
950 struct strbuf *err)
951 {
952 struct ref_transaction *tr;
953 assert(err);
954
955 tr = xcalloc(1, sizeof(struct ref_transaction));
956 tr->ref_store = refs;
957 return tr;
958 }
959
960 struct ref_transaction *ref_transaction_begin(struct strbuf *err)
961 {
962 return ref_store_transaction_begin(get_main_ref_store(the_repository), err);
963 }
964
965 void ref_transaction_free(struct ref_transaction *transaction)
966 {
967 size_t i;
968
969 if (!transaction)
970 return;
971
972 switch (transaction->state) {
973 case REF_TRANSACTION_OPEN:
974 case REF_TRANSACTION_CLOSED:
975 /* OK */
976 break;
977 case REF_TRANSACTION_PREPARED:
978 BUG("free called on a prepared reference transaction");
979 break;
980 default:
981 BUG("unexpected reference transaction state");
982 break;
983 }
984
985 for (i = 0; i < transaction->nr; i++) {
986 free(transaction->updates[i]->msg);
987 free(transaction->updates[i]);
988 }
989 free(transaction->updates);
990 free(transaction);
991 }
992
993 struct ref_update *ref_transaction_add_update(
994 struct ref_transaction *transaction,
995 const char *refname, unsigned int flags,
996 const struct object_id *new_oid,
997 const struct object_id *old_oid,
998 const char *msg)
999 {
1000 struct ref_update *update;
1001
1002 if (transaction->state != REF_TRANSACTION_OPEN)
1003 BUG("update called for transaction that is not open");
1004
1005 FLEX_ALLOC_STR(update, refname, refname);
1006 ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
1007 transaction->updates[transaction->nr++] = update;
1008
1009 update->flags = flags;
1010
1011 if (flags & REF_HAVE_NEW)
1012 oidcpy(&update->new_oid, new_oid);
1013 if (flags & REF_HAVE_OLD)
1014 oidcpy(&update->old_oid, old_oid);
1015 update->msg = xstrdup_or_null(msg);
1016 return update;
1017 }
1018
1019 int ref_transaction_update(struct ref_transaction *transaction,
1020 const char *refname,
1021 const struct object_id *new_oid,
1022 const struct object_id *old_oid,
1023 unsigned int flags, const char *msg,
1024 struct strbuf *err)
1025 {
1026 assert(err);
1027
1028 if ((new_oid && !is_null_oid(new_oid)) ?
1029 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
1030 !refname_is_safe(refname)) {
1031 strbuf_addf(err, "refusing to update ref with bad name '%s'",
1032 refname);
1033 return -1;
1034 }
1035
1036 if (flags & ~REF_TRANSACTION_UPDATE_ALLOWED_FLAGS)
1037 BUG("illegal flags 0x%x passed to ref_transaction_update()", flags);
1038
1039 flags |= (new_oid ? REF_HAVE_NEW : 0) | (old_oid ? REF_HAVE_OLD : 0);
1040
1041 ref_transaction_add_update(transaction, refname, flags,
1042 new_oid, old_oid, msg);
1043 return 0;
1044 }
1045
1046 int ref_transaction_create(struct ref_transaction *transaction,
1047 const char *refname,
1048 const struct object_id *new_oid,
1049 unsigned int flags, const char *msg,
1050 struct strbuf *err)
1051 {
1052 if (!new_oid || is_null_oid(new_oid))
1053 BUG("create called without valid new_oid");
1054 return ref_transaction_update(transaction, refname, new_oid,
1055 &null_oid, flags, msg, err);
1056 }
1057
1058 int ref_transaction_delete(struct ref_transaction *transaction,
1059 const char *refname,
1060 const struct object_id *old_oid,
1061 unsigned int flags, const char *msg,
1062 struct strbuf *err)
1063 {
1064 if (old_oid && is_null_oid(old_oid))
1065 BUG("delete called with old_oid set to zeros");
1066 return ref_transaction_update(transaction, refname,
1067 &null_oid, old_oid,
1068 flags, msg, err);
1069 }
1070
1071 int ref_transaction_verify(struct ref_transaction *transaction,
1072 const char *refname,
1073 const struct object_id *old_oid,
1074 unsigned int flags,
1075 struct strbuf *err)
1076 {
1077 if (!old_oid)
1078 BUG("verify called with old_oid set to NULL");
1079 return ref_transaction_update(transaction, refname,
1080 NULL, old_oid,
1081 flags, NULL, err);
1082 }
1083
1084 int refs_update_ref(struct ref_store *refs, const char *msg,
1085 const char *refname, const struct object_id *new_oid,
1086 const struct object_id *old_oid, unsigned int flags,
1087 enum action_on_err onerr)
1088 {
1089 struct ref_transaction *t = NULL;
1090 struct strbuf err = STRBUF_INIT;
1091 int ret = 0;
1092
1093 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
1094 assert(refs == get_main_ref_store(the_repository));
1095 ret = write_pseudoref(refname, new_oid, old_oid, &err);
1096 } else {
1097 t = ref_store_transaction_begin(refs, &err);
1098 if (!t ||
1099 ref_transaction_update(t, refname, new_oid, old_oid,
1100 flags, msg, &err) ||
1101 ref_transaction_commit(t, &err)) {
1102 ret = 1;
1103 ref_transaction_free(t);
1104 }
1105 }
1106 if (ret) {
1107 const char *str = "update_ref failed for ref '%s': %s";
1108
1109 switch (onerr) {
1110 case UPDATE_REFS_MSG_ON_ERR:
1111 error(str, refname, err.buf);
1112 break;
1113 case UPDATE_REFS_DIE_ON_ERR:
1114 die(str, refname, err.buf);
1115 break;
1116 case UPDATE_REFS_QUIET_ON_ERR:
1117 break;
1118 }
1119 strbuf_release(&err);
1120 return 1;
1121 }
1122 strbuf_release(&err);
1123 if (t)
1124 ref_transaction_free(t);
1125 return 0;
1126 }
1127
1128 int update_ref(const char *msg, const char *refname,
1129 const struct object_id *new_oid,
1130 const struct object_id *old_oid,
1131 unsigned int flags, enum action_on_err onerr)
1132 {
1133 return refs_update_ref(get_main_ref_store(the_repository), msg, refname, new_oid,
1134 old_oid, flags, onerr);
1135 }
1136
1137 char *shorten_unambiguous_ref(const char *refname, int strict)
1138 {
1139 int i;
1140 static char **scanf_fmts;
1141 static int nr_rules;
1142 char *short_name;
1143 struct strbuf resolved_buf = STRBUF_INIT;
1144
1145 if (!nr_rules) {
1146 /*
1147 * Pre-generate scanf formats from ref_rev_parse_rules[].
1148 * Generate a format suitable for scanf from a
1149 * ref_rev_parse_rules rule by interpolating "%s" at the
1150 * location of the "%.*s".
1151 */
1152 size_t total_len = 0;
1153 size_t offset = 0;
1154
1155 /* the rule list is NULL terminated, count them first */
1156 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
1157 /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
1158 total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
1159
1160 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
1161
1162 offset = 0;
1163 for (i = 0; i < nr_rules; i++) {
1164 assert(offset < total_len);
1165 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
1166 offset += xsnprintf(scanf_fmts[i], total_len - offset,
1167 ref_rev_parse_rules[i], 2, "%s") + 1;
1168 }
1169 }
1170
1171 /* bail out if there are no rules */
1172 if (!nr_rules)
1173 return xstrdup(refname);
1174
1175 /* buffer for scanf result, at most refname must fit */
1176 short_name = xstrdup(refname);
1177
1178 /* skip first rule, it will always match */
1179 for (i = nr_rules - 1; i > 0 ; --i) {
1180 int j;
1181 int rules_to_fail = i;
1182 int short_name_len;
1183
1184 if (1 != sscanf(refname, scanf_fmts[i], short_name))
1185 continue;
1186
1187 short_name_len = strlen(short_name);
1188
1189 /*
1190 * in strict mode, all (except the matched one) rules
1191 * must fail to resolve to a valid non-ambiguous ref
1192 */
1193 if (strict)
1194 rules_to_fail = nr_rules;
1195
1196 /*
1197 * check if the short name resolves to a valid ref,
1198 * but use only rules prior to the matched one
1199 */
1200 for (j = 0; j < rules_to_fail; j++) {
1201 const char *rule = ref_rev_parse_rules[j];
1202
1203 /* skip matched rule */
1204 if (i == j)
1205 continue;
1206
1207 /*
1208 * the short name is ambiguous, if it resolves
1209 * (with this previous rule) to a valid ref
1210 * read_ref() returns 0 on success
1211 */
1212 strbuf_reset(&resolved_buf);
1213 strbuf_addf(&resolved_buf, rule,
1214 short_name_len, short_name);
1215 if (ref_exists(resolved_buf.buf))
1216 break;
1217 }
1218
1219 /*
1220 * short name is non-ambiguous if all previous rules
1221 * haven't resolved to a valid ref
1222 */
1223 if (j == rules_to_fail) {
1224 strbuf_release(&resolved_buf);
1225 return short_name;
1226 }
1227 }
1228
1229 strbuf_release(&resolved_buf);
1230 free(short_name);
1231 return xstrdup(refname);
1232 }
1233
1234 static struct string_list *hide_refs;
1235
1236 int parse_hide_refs_config(const char *var, const char *value, const char *section)
1237 {
1238 const char *key;
1239 if (!strcmp("transfer.hiderefs", var) ||
1240 (!parse_config_key(var, section, NULL, NULL, &key) &&
1241 !strcmp(key, "hiderefs"))) {
1242 char *ref;
1243 int len;
1244
1245 if (!value)
1246 return config_error_nonbool(var);
1247 ref = xstrdup(value);
1248 len = strlen(ref);
1249 while (len && ref[len - 1] == '/')
1250 ref[--len] = '\0';
1251 if (!hide_refs) {
1252 hide_refs = xcalloc(1, sizeof(*hide_refs));
1253 hide_refs->strdup_strings = 1;
1254 }
1255 string_list_append(hide_refs, ref);
1256 }
1257 return 0;
1258 }
1259
1260 int ref_is_hidden(const char *refname, const char *refname_full)
1261 {
1262 int i;
1263
1264 if (!hide_refs)
1265 return 0;
1266 for (i = hide_refs->nr - 1; i >= 0; i--) {
1267 const char *match = hide_refs->items[i].string;
1268 const char *subject;
1269 int neg = 0;
1270 const char *p;
1271
1272 if (*match == '!') {
1273 neg = 1;
1274 match++;
1275 }
1276
1277 if (*match == '^') {
1278 subject = refname_full;
1279 match++;
1280 } else {
1281 subject = refname;
1282 }
1283
1284 /* refname can be NULL when namespaces are used. */
1285 if (subject &&
1286 skip_prefix(subject, match, &p) &&
1287 (!*p || *p == '/'))
1288 return !neg;
1289 }
1290 return 0;
1291 }
1292
1293 const char *find_descendant_ref(const char *dirname,
1294 const struct string_list *extras,
1295 const struct string_list *skip)
1296 {
1297 int pos;
1298
1299 if (!extras)
1300 return NULL;
1301
1302 /*
1303 * Look at the place where dirname would be inserted into
1304 * extras. If there is an entry at that position that starts
1305 * with dirname (remember, dirname includes the trailing
1306 * slash) and is not in skip, then we have a conflict.
1307 */
1308 for (pos = string_list_find_insert_index(extras, dirname, 0);
1309 pos < extras->nr; pos++) {
1310 const char *extra_refname = extras->items[pos].string;
1311
1312 if (!starts_with(extra_refname, dirname))
1313 break;
1314
1315 if (!skip || !string_list_has_string(skip, extra_refname))
1316 return extra_refname;
1317 }
1318 return NULL;
1319 }
1320
1321 int refs_rename_ref_available(struct ref_store *refs,
1322 const char *old_refname,
1323 const char *new_refname)
1324 {
1325 struct string_list skip = STRING_LIST_INIT_NODUP;
1326 struct strbuf err = STRBUF_INIT;
1327 int ok;
1328
1329 string_list_insert(&skip, old_refname);
1330 ok = !refs_verify_refname_available(refs, new_refname,
1331 NULL, &skip, &err);
1332 if (!ok)
1333 error("%s", err.buf);
1334
1335 string_list_clear(&skip, 0);
1336 strbuf_release(&err);
1337 return ok;
1338 }
1339
1340 int refs_head_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1341 {
1342 struct object_id oid;
1343 int flag;
1344
1345 if (!refs_read_ref_full(refs, "HEAD", RESOLVE_REF_READING,
1346 &oid, &flag))
1347 return fn("HEAD", &oid, flag, cb_data);
1348
1349 return 0;
1350 }
1351
1352 int head_ref(each_ref_fn fn, void *cb_data)
1353 {
1354 return refs_head_ref(get_main_ref_store(the_repository), fn, cb_data);
1355 }
1356
1357 struct ref_iterator *refs_ref_iterator_begin(
1358 struct ref_store *refs,
1359 const char *prefix, int trim, int flags)
1360 {
1361 struct ref_iterator *iter;
1362
1363 if (ref_paranoia < 0)
1364 ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
1365 if (ref_paranoia)
1366 flags |= DO_FOR_EACH_INCLUDE_BROKEN;
1367
1368 iter = refs->be->iterator_begin(refs, prefix, flags);
1369
1370 /*
1371 * `iterator_begin()` already takes care of prefix, but we
1372 * might need to do some trimming:
1373 */
1374 if (trim)
1375 iter = prefix_ref_iterator_begin(iter, "", trim);
1376
1377 /* Sanity check for subclasses: */
1378 if (!iter->ordered)
1379 BUG("reference iterator is not ordered");
1380
1381 return iter;
1382 }
1383
1384 /*
1385 * Call fn for each reference in the specified submodule for which the
1386 * refname begins with prefix. If trim is non-zero, then trim that
1387 * many characters off the beginning of each refname before passing
1388 * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1389 * include broken references in the iteration. If fn ever returns a
1390 * non-zero value, stop the iteration and return that value;
1391 * otherwise, return 0.
1392 */
1393 static int do_for_each_ref(struct ref_store *refs, const char *prefix,
1394 each_ref_fn fn, int trim, int flags, void *cb_data)
1395 {
1396 struct ref_iterator *iter;
1397
1398 if (!refs)
1399 return 0;
1400
1401 iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1402
1403 return do_for_each_ref_iterator(iter, fn, cb_data);
1404 }
1405
1406 int refs_for_each_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1407 {
1408 return do_for_each_ref(refs, "", fn, 0, 0, cb_data);
1409 }
1410
1411 int for_each_ref(each_ref_fn fn, void *cb_data)
1412 {
1413 return refs_for_each_ref(get_main_ref_store(the_repository), fn, cb_data);
1414 }
1415
1416 int refs_for_each_ref_in(struct ref_store *refs, const char *prefix,
1417 each_ref_fn fn, void *cb_data)
1418 {
1419 return do_for_each_ref(refs, prefix, fn, strlen(prefix), 0, cb_data);
1420 }
1421
1422 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1423 {
1424 return refs_for_each_ref_in(get_main_ref_store(the_repository), prefix, fn, cb_data);
1425 }
1426
1427 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1428 {
1429 unsigned int flag = 0;
1430
1431 if (broken)
1432 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1433 return do_for_each_ref(get_main_ref_store(the_repository),
1434 prefix, fn, 0, flag, cb_data);
1435 }
1436
1437 int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix,
1438 each_ref_fn fn, void *cb_data,
1439 unsigned int broken)
1440 {
1441 unsigned int flag = 0;
1442
1443 if (broken)
1444 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1445 return do_for_each_ref(refs, prefix, fn, 0, flag, cb_data);
1446 }
1447
1448 int for_each_replace_ref(struct repository *r, each_ref_fn fn, void *cb_data)
1449 {
1450 return do_for_each_ref(get_main_ref_store(r),
1451 git_replace_ref_base, fn,
1452 strlen(git_replace_ref_base),
1453 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1454 }
1455
1456 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1457 {
1458 struct strbuf buf = STRBUF_INIT;
1459 int ret;
1460 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1461 ret = do_for_each_ref(get_main_ref_store(the_repository),
1462 buf.buf, fn, 0, 0, cb_data);
1463 strbuf_release(&buf);
1464 return ret;
1465 }
1466
1467 int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1468 {
1469 return do_for_each_ref(refs, "", fn, 0,
1470 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1471 }
1472
1473 int for_each_rawref(each_ref_fn fn, void *cb_data)
1474 {
1475 return refs_for_each_rawref(get_main_ref_store(the_repository), fn, cb_data);
1476 }
1477
1478 int refs_read_raw_ref(struct ref_store *ref_store,
1479 const char *refname, struct object_id *oid,
1480 struct strbuf *referent, unsigned int *type)
1481 {
1482 return ref_store->be->read_raw_ref(ref_store, refname, oid, referent, type);
1483 }
1484
1485 /* This function needs to return a meaningful errno on failure */
1486 const char *refs_resolve_ref_unsafe(struct ref_store *refs,
1487 const char *refname,
1488 int resolve_flags,
1489 struct object_id *oid, int *flags)
1490 {
1491 static struct strbuf sb_refname = STRBUF_INIT;
1492 struct object_id unused_oid;
1493 int unused_flags;
1494 int symref_count;
1495
1496 if (!oid)
1497 oid = &unused_oid;
1498 if (!flags)
1499 flags = &unused_flags;
1500
1501 *flags = 0;
1502
1503 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1504 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1505 !refname_is_safe(refname)) {
1506 errno = EINVAL;
1507 return NULL;
1508 }
1509
1510 /*
1511 * dwim_ref() uses REF_ISBROKEN to distinguish between
1512 * missing refs and refs that were present but invalid,
1513 * to complain about the latter to stderr.
1514 *
1515 * We don't know whether the ref exists, so don't set
1516 * REF_ISBROKEN yet.
1517 */
1518 *flags |= REF_BAD_NAME;
1519 }
1520
1521 for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1522 unsigned int read_flags = 0;
1523
1524 if (refs_read_raw_ref(refs, refname,
1525 oid, &sb_refname, &read_flags)) {
1526 *flags |= read_flags;
1527
1528 /* In reading mode, refs must eventually resolve */
1529 if (resolve_flags & RESOLVE_REF_READING)
1530 return NULL;
1531
1532 /*
1533 * Otherwise a missing ref is OK. But the files backend
1534 * may show errors besides ENOENT if there are
1535 * similarly-named refs.
1536 */
1537 if (errno != ENOENT &&
1538 errno != EISDIR &&
1539 errno != ENOTDIR)
1540 return NULL;
1541
1542 oidclr(oid);
1543 if (*flags & REF_BAD_NAME)
1544 *flags |= REF_ISBROKEN;
1545 return refname;
1546 }
1547
1548 *flags |= read_flags;
1549
1550 if (!(read_flags & REF_ISSYMREF)) {
1551 if (*flags & REF_BAD_NAME) {
1552 oidclr(oid);
1553 *flags |= REF_ISBROKEN;
1554 }
1555 return refname;
1556 }
1557
1558 refname = sb_refname.buf;
1559 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1560 oidclr(oid);
1561 return refname;
1562 }
1563 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1564 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1565 !refname_is_safe(refname)) {
1566 errno = EINVAL;
1567 return NULL;
1568 }
1569
1570 *flags |= REF_ISBROKEN | REF_BAD_NAME;
1571 }
1572 }
1573
1574 errno = ELOOP;
1575 return NULL;
1576 }
1577
1578 /* backend functions */
1579 int refs_init_db(struct strbuf *err)
1580 {
1581 struct ref_store *refs = get_main_ref_store(the_repository);
1582
1583 return refs->be->init_db(refs, err);
1584 }
1585
1586 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1587 struct object_id *oid, int *flags)
1588 {
1589 return refs_resolve_ref_unsafe(get_main_ref_store(the_repository), refname,
1590 resolve_flags, oid, flags);
1591 }
1592
1593 int resolve_gitlink_ref(const char *submodule, const char *refname,
1594 struct object_id *oid)
1595 {
1596 struct ref_store *refs;
1597 int flags;
1598
1599 refs = get_submodule_ref_store(submodule);
1600
1601 if (!refs)
1602 return -1;
1603
1604 if (!refs_resolve_ref_unsafe(refs, refname, 0, oid, &flags) ||
1605 is_null_oid(oid))
1606 return -1;
1607 return 0;
1608 }
1609
1610 struct ref_store_hash_entry
1611 {
1612 struct hashmap_entry ent; /* must be the first member! */
1613
1614 struct ref_store *refs;
1615
1616 /* NUL-terminated identifier of the ref store: */
1617 char name[FLEX_ARRAY];
1618 };
1619
1620 static int ref_store_hash_cmp(const void *unused_cmp_data,
1621 const void *entry, const void *entry_or_key,
1622 const void *keydata)
1623 {
1624 const struct ref_store_hash_entry *e1 = entry, *e2 = entry_or_key;
1625 const char *name = keydata ? keydata : e2->name;
1626
1627 return strcmp(e1->name, name);
1628 }
1629
1630 static struct ref_store_hash_entry *alloc_ref_store_hash_entry(
1631 const char *name, struct ref_store *refs)
1632 {
1633 struct ref_store_hash_entry *entry;
1634
1635 FLEX_ALLOC_STR(entry, name, name);
1636 hashmap_entry_init(entry, strhash(name));
1637 entry->refs = refs;
1638 return entry;
1639 }
1640
1641 /* A hashmap of ref_stores, stored by submodule name: */
1642 static struct hashmap submodule_ref_stores;
1643
1644 /* A hashmap of ref_stores, stored by worktree id: */
1645 static struct hashmap worktree_ref_stores;
1646
1647 /*
1648 * Look up a ref store by name. If that ref_store hasn't been
1649 * registered yet, return NULL.
1650 */
1651 static struct ref_store *lookup_ref_store_map(struct hashmap *map,
1652 const char *name)
1653 {
1654 struct ref_store_hash_entry *entry;
1655
1656 if (!map->tablesize)
1657 /* It's initialized on demand in register_ref_store(). */
1658 return NULL;
1659
1660 entry = hashmap_get_from_hash(map, strhash(name), name);
1661 return entry ? entry->refs : NULL;
1662 }
1663
1664 /*
1665 * Create, record, and return a ref_store instance for the specified
1666 * gitdir.
1667 */
1668 static struct ref_store *ref_store_init(const char *gitdir,
1669 unsigned int flags)
1670 {
1671 const char *be_name = "files";
1672 struct ref_storage_be *be = find_ref_storage_backend(be_name);
1673 struct ref_store *refs;
1674
1675 if (!be)
1676 BUG("reference backend %s is unknown", be_name);
1677
1678 refs = be->init(gitdir, flags);
1679 return refs;
1680 }
1681
1682 struct ref_store *get_main_ref_store(struct repository *r)
1683 {
1684 if (r->refs)
1685 return r->refs;
1686
1687 if (!r->gitdir)
1688 BUG("attempting to get main_ref_store outside of repository");
1689
1690 r->refs = ref_store_init(r->gitdir, REF_STORE_ALL_CAPS);
1691 return r->refs;
1692 }
1693
1694 /*
1695 * Associate a ref store with a name. It is a fatal error to call this
1696 * function twice for the same name.
1697 */
1698 static void register_ref_store_map(struct hashmap *map,
1699 const char *type,
1700 struct ref_store *refs,
1701 const char *name)
1702 {
1703 if (!map->tablesize)
1704 hashmap_init(map, ref_store_hash_cmp, NULL, 0);
1705
1706 if (hashmap_put(map, alloc_ref_store_hash_entry(name, refs)))
1707 BUG("%s ref_store '%s' initialized twice", type, name);
1708 }
1709
1710 struct ref_store *get_submodule_ref_store(const char *submodule)
1711 {
1712 struct strbuf submodule_sb = STRBUF_INIT;
1713 struct ref_store *refs;
1714 char *to_free = NULL;
1715 size_t len;
1716
1717 if (!submodule)
1718 return NULL;
1719
1720 len = strlen(submodule);
1721 while (len && is_dir_sep(submodule[len - 1]))
1722 len--;
1723 if (!len)
1724 return NULL;
1725
1726 if (submodule[len])
1727 /* We need to strip off one or more trailing slashes */
1728 submodule = to_free = xmemdupz(submodule, len);
1729
1730 refs = lookup_ref_store_map(&submodule_ref_stores, submodule);
1731 if (refs)
1732 goto done;
1733
1734 strbuf_addstr(&submodule_sb, submodule);
1735 if (!is_nonbare_repository_dir(&submodule_sb))
1736 goto done;
1737
1738 if (submodule_to_gitdir(&submodule_sb, submodule))
1739 goto done;
1740
1741 /* assume that add_submodule_odb() has been called */
1742 refs = ref_store_init(submodule_sb.buf,
1743 REF_STORE_READ | REF_STORE_ODB);
1744 register_ref_store_map(&submodule_ref_stores, "submodule",
1745 refs, submodule);
1746
1747 done:
1748 strbuf_release(&submodule_sb);
1749 free(to_free);
1750
1751 return refs;
1752 }
1753
1754 struct ref_store *get_worktree_ref_store(const struct worktree *wt)
1755 {
1756 struct ref_store *refs;
1757 const char *id;
1758
1759 if (wt->is_current)
1760 return get_main_ref_store(the_repository);
1761
1762 id = wt->id ? wt->id : "/";
1763 refs = lookup_ref_store_map(&worktree_ref_stores, id);
1764 if (refs)
1765 return refs;
1766
1767 if (wt->id)
1768 refs = ref_store_init(git_common_path("worktrees/%s", wt->id),
1769 REF_STORE_ALL_CAPS);
1770 else
1771 refs = ref_store_init(get_git_common_dir(),
1772 REF_STORE_ALL_CAPS);
1773
1774 if (refs)
1775 register_ref_store_map(&worktree_ref_stores, "worktree",
1776 refs, id);
1777 return refs;
1778 }
1779
1780 void base_ref_store_init(struct ref_store *refs,
1781 const struct ref_storage_be *be)
1782 {
1783 refs->be = be;
1784 }
1785
1786 /* backend functions */
1787 int refs_pack_refs(struct ref_store *refs, unsigned int flags)
1788 {
1789 return refs->be->pack_refs(refs, flags);
1790 }
1791
1792 int refs_peel_ref(struct ref_store *refs, const char *refname,
1793 struct object_id *oid)
1794 {
1795 int flag;
1796 struct object_id base;
1797
1798 if (current_ref_iter && current_ref_iter->refname == refname) {
1799 struct object_id peeled;
1800
1801 if (ref_iterator_peel(current_ref_iter, &peeled))
1802 return -1;
1803 oidcpy(oid, &peeled);
1804 return 0;
1805 }
1806
1807 if (refs_read_ref_full(refs, refname,
1808 RESOLVE_REF_READING, &base, &flag))
1809 return -1;
1810
1811 return peel_object(&base, oid);
1812 }
1813
1814 int peel_ref(const char *refname, struct object_id *oid)
1815 {
1816 return refs_peel_ref(get_main_ref_store(the_repository), refname, oid);
1817 }
1818
1819 int refs_create_symref(struct ref_store *refs,
1820 const char *ref_target,
1821 const char *refs_heads_master,
1822 const char *logmsg)
1823 {
1824 return refs->be->create_symref(refs, ref_target,
1825 refs_heads_master,
1826 logmsg);
1827 }
1828
1829 int create_symref(const char *ref_target, const char *refs_heads_master,
1830 const char *logmsg)
1831 {
1832 return refs_create_symref(get_main_ref_store(the_repository), ref_target,
1833 refs_heads_master, logmsg);
1834 }
1835
1836 int ref_update_reject_duplicates(struct string_list *refnames,
1837 struct strbuf *err)
1838 {
1839 size_t i, n = refnames->nr;
1840
1841 assert(err);
1842
1843 for (i = 1; i < n; i++) {
1844 int cmp = strcmp(refnames->items[i - 1].string,
1845 refnames->items[i].string);
1846
1847 if (!cmp) {
1848 strbuf_addf(err,
1849 "multiple updates for ref '%s' not allowed.",
1850 refnames->items[i].string);
1851 return 1;
1852 } else if (cmp > 0) {
1853 BUG("ref_update_reject_duplicates() received unsorted list");
1854 }
1855 }
1856 return 0;
1857 }
1858
1859 int ref_transaction_prepare(struct ref_transaction *transaction,
1860 struct strbuf *err)
1861 {
1862 struct ref_store *refs = transaction->ref_store;
1863
1864 switch (transaction->state) {
1865 case REF_TRANSACTION_OPEN:
1866 /* Good. */
1867 break;
1868 case REF_TRANSACTION_PREPARED:
1869 BUG("prepare called twice on reference transaction");
1870 break;
1871 case REF_TRANSACTION_CLOSED:
1872 BUG("prepare called on a closed reference transaction");
1873 break;
1874 default:
1875 BUG("unexpected reference transaction state");
1876 break;
1877 }
1878
1879 if (getenv(GIT_QUARANTINE_ENVIRONMENT)) {
1880 strbuf_addstr(err,
1881 _("ref updates forbidden inside quarantine environment"));
1882 return -1;
1883 }
1884
1885 return refs->be->transaction_prepare(refs, transaction, err);
1886 }
1887
1888 int ref_transaction_abort(struct ref_transaction *transaction,
1889 struct strbuf *err)
1890 {
1891 struct ref_store *refs = transaction->ref_store;
1892 int ret = 0;
1893
1894 switch (transaction->state) {
1895 case REF_TRANSACTION_OPEN:
1896 /* No need to abort explicitly. */
1897 break;
1898 case REF_TRANSACTION_PREPARED:
1899 ret = refs->be->transaction_abort(refs, transaction, err);
1900 break;
1901 case REF_TRANSACTION_CLOSED:
1902 BUG("abort called on a closed reference transaction");
1903 break;
1904 default:
1905 BUG("unexpected reference transaction state");
1906 break;
1907 }
1908
1909 ref_transaction_free(transaction);
1910 return ret;
1911 }
1912
1913 int ref_transaction_commit(struct ref_transaction *transaction,
1914 struct strbuf *err)
1915 {
1916 struct ref_store *refs = transaction->ref_store;
1917 int ret;
1918
1919 switch (transaction->state) {
1920 case REF_TRANSACTION_OPEN:
1921 /* Need to prepare first. */
1922 ret = ref_transaction_prepare(transaction, err);
1923 if (ret)
1924 return ret;
1925 break;
1926 case REF_TRANSACTION_PREPARED:
1927 /* Fall through to finish. */
1928 break;
1929 case REF_TRANSACTION_CLOSED:
1930 BUG("commit called on a closed reference transaction");
1931 break;
1932 default:
1933 BUG("unexpected reference transaction state");
1934 break;
1935 }
1936
1937 return refs->be->transaction_finish(refs, transaction, err);
1938 }
1939
1940 int refs_verify_refname_available(struct ref_store *refs,
1941 const char *refname,
1942 const struct string_list *extras,
1943 const struct string_list *skip,
1944 struct strbuf *err)
1945 {
1946 const char *slash;
1947 const char *extra_refname;
1948 struct strbuf dirname = STRBUF_INIT;
1949 struct strbuf referent = STRBUF_INIT;
1950 struct object_id oid;
1951 unsigned int type;
1952 struct ref_iterator *iter;
1953 int ok;
1954 int ret = -1;
1955
1956 /*
1957 * For the sake of comments in this function, suppose that
1958 * refname is "refs/foo/bar".
1959 */
1960
1961 assert(err);
1962
1963 strbuf_grow(&dirname, strlen(refname) + 1);
1964 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
1965 /* Expand dirname to the new prefix, not including the trailing slash: */
1966 strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
1967
1968 /*
1969 * We are still at a leading dir of the refname (e.g.,
1970 * "refs/foo"; if there is a reference with that name,
1971 * it is a conflict, *unless* it is in skip.
1972 */
1973 if (skip && string_list_has_string(skip, dirname.buf))
1974 continue;
1975
1976 if (!refs_read_raw_ref(refs, dirname.buf, &oid, &referent, &type)) {
1977 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1978 dirname.buf, refname);
1979 goto cleanup;
1980 }
1981
1982 if (extras && string_list_has_string(extras, dirname.buf)) {
1983 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1984 refname, dirname.buf);
1985 goto cleanup;
1986 }
1987 }
1988
1989 /*
1990 * We are at the leaf of our refname (e.g., "refs/foo/bar").
1991 * There is no point in searching for a reference with that
1992 * name, because a refname isn't considered to conflict with
1993 * itself. But we still need to check for references whose
1994 * names are in the "refs/foo/bar/" namespace, because they
1995 * *do* conflict.
1996 */
1997 strbuf_addstr(&dirname, refname + dirname.len);
1998 strbuf_addch(&dirname, '/');
1999
2000 iter = refs_ref_iterator_begin(refs, dirname.buf, 0,
2001 DO_FOR_EACH_INCLUDE_BROKEN);
2002 while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
2003 if (skip &&
2004 string_list_has_string(skip, iter->refname))
2005 continue;
2006
2007 strbuf_addf(err, "'%s' exists; cannot create '%s'",
2008 iter->refname, refname);
2009 ref_iterator_abort(iter);
2010 goto cleanup;
2011 }
2012
2013 if (ok != ITER_DONE)
2014 BUG("error while iterating over references");
2015
2016 extra_refname = find_descendant_ref(dirname.buf, extras, skip);
2017 if (extra_refname)
2018 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
2019 refname, extra_refname);
2020 else
2021 ret = 0;
2022
2023 cleanup:
2024 strbuf_release(&referent);
2025 strbuf_release(&dirname);
2026 return ret;
2027 }
2028
2029 int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2030 {
2031 struct ref_iterator *iter;
2032
2033 iter = refs->be->reflog_iterator_begin(refs);
2034
2035 return do_for_each_ref_iterator(iter, fn, cb_data);
2036 }
2037
2038 int for_each_reflog(each_ref_fn fn, void *cb_data)
2039 {
2040 return refs_for_each_reflog(get_main_ref_store(the_repository), fn, cb_data);
2041 }
2042
2043 int refs_for_each_reflog_ent_reverse(struct ref_store *refs,
2044 const char *refname,
2045 each_reflog_ent_fn fn,
2046 void *cb_data)
2047 {
2048 return refs->be->for_each_reflog_ent_reverse(refs, refname,
2049 fn, cb_data);
2050 }
2051
2052 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
2053 void *cb_data)
2054 {
2055 return refs_for_each_reflog_ent_reverse(get_main_ref_store(the_repository),
2056 refname, fn, cb_data);
2057 }
2058
2059 int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname,
2060 each_reflog_ent_fn fn, void *cb_data)
2061 {
2062 return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
2063 }
2064
2065 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
2066 void *cb_data)
2067 {
2068 return refs_for_each_reflog_ent(get_main_ref_store(the_repository), refname,
2069 fn, cb_data);
2070 }
2071
2072 int refs_reflog_exists(struct ref_store *refs, const char *refname)
2073 {
2074 return refs->be->reflog_exists(refs, refname);
2075 }
2076
2077 int reflog_exists(const char *refname)
2078 {
2079 return refs_reflog_exists(get_main_ref_store(the_repository), refname);
2080 }
2081
2082 int refs_create_reflog(struct ref_store *refs, const char *refname,
2083 int force_create, struct strbuf *err)
2084 {
2085 return refs->be->create_reflog(refs, refname, force_create, err);
2086 }
2087
2088 int safe_create_reflog(const char *refname, int force_create,
2089 struct strbuf *err)
2090 {
2091 return refs_create_reflog(get_main_ref_store(the_repository), refname,
2092 force_create, err);
2093 }
2094
2095 int refs_delete_reflog(struct ref_store *refs, const char *refname)
2096 {
2097 return refs->be->delete_reflog(refs, refname);
2098 }
2099
2100 int delete_reflog(const char *refname)
2101 {
2102 return refs_delete_reflog(get_main_ref_store(the_repository), refname);
2103 }
2104
2105 int refs_reflog_expire(struct ref_store *refs,
2106 const char *refname, const struct object_id *oid,
2107 unsigned int flags,
2108 reflog_expiry_prepare_fn prepare_fn,
2109 reflog_expiry_should_prune_fn should_prune_fn,
2110 reflog_expiry_cleanup_fn cleanup_fn,
2111 void *policy_cb_data)
2112 {
2113 return refs->be->reflog_expire(refs, refname, oid, flags,
2114 prepare_fn, should_prune_fn,
2115 cleanup_fn, policy_cb_data);
2116 }
2117
2118 int reflog_expire(const char *refname, const struct object_id *oid,
2119 unsigned int flags,
2120 reflog_expiry_prepare_fn prepare_fn,
2121 reflog_expiry_should_prune_fn should_prune_fn,
2122 reflog_expiry_cleanup_fn cleanup_fn,
2123 void *policy_cb_data)
2124 {
2125 return refs_reflog_expire(get_main_ref_store(the_repository),
2126 refname, oid, flags,
2127 prepare_fn, should_prune_fn,
2128 cleanup_fn, policy_cb_data);
2129 }
2130
2131 int initial_ref_transaction_commit(struct ref_transaction *transaction,
2132 struct strbuf *err)
2133 {
2134 struct ref_store *refs = transaction->ref_store;
2135
2136 return refs->be->initial_transaction_commit(refs, transaction, err);
2137 }
2138
2139 int refs_delete_refs(struct ref_store *refs, const char *msg,
2140 struct string_list *refnames, unsigned int flags)
2141 {
2142 return refs->be->delete_refs(refs, msg, refnames, flags);
2143 }
2144
2145 int delete_refs(const char *msg, struct string_list *refnames,
2146 unsigned int flags)
2147 {
2148 return refs_delete_refs(get_main_ref_store(the_repository), msg, refnames, flags);
2149 }
2150
2151 int refs_rename_ref(struct ref_store *refs, const char *oldref,
2152 const char *newref, const char *logmsg)
2153 {
2154 return refs->be->rename_ref(refs, oldref, newref, logmsg);
2155 }
2156
2157 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
2158 {
2159 return refs_rename_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2160 }
2161
2162 int refs_copy_existing_ref(struct ref_store *refs, const char *oldref,
2163 const char *newref, const char *logmsg)
2164 {
2165 return refs->be->copy_ref(refs, oldref, newref, logmsg);
2166 }
2167
2168 int copy_existing_ref(const char *oldref, const char *newref, const char *logmsg)
2169 {
2170 return refs_copy_existing_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2171 }