Merge branch 'jt/refspec-dwim-precedence-fix'
[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(the_repository, 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 #define NUM_REV_PARSE_RULES (ARRAY_SIZE(ref_rev_parse_rules) - 1)
494
495 /*
496 * Is it possible that the caller meant full_name with abbrev_name?
497 * If so return a non-zero value to signal "yes"; the magnitude of
498 * the returned value gives the precedence used for disambiguation.
499 *
500 * If abbrev_name cannot mean full_name, return 0.
501 */
502 int refname_match(const char *abbrev_name, const char *full_name)
503 {
504 const char **p;
505 const int abbrev_name_len = strlen(abbrev_name);
506 const int num_rules = NUM_REV_PARSE_RULES;
507
508 for (p = ref_rev_parse_rules; *p; p++)
509 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name)))
510 return &ref_rev_parse_rules[num_rules] - p;
511
512 return 0;
513 }
514
515 /*
516 * Given a 'prefix' expand it by the rules in 'ref_rev_parse_rules' and add
517 * the results to 'prefixes'
518 */
519 void expand_ref_prefix(struct argv_array *prefixes, const char *prefix)
520 {
521 const char **p;
522 int len = strlen(prefix);
523
524 for (p = ref_rev_parse_rules; *p; p++)
525 argv_array_pushf(prefixes, *p, len, prefix);
526 }
527
528 /*
529 * *string and *len will only be substituted, and *string returned (for
530 * later free()ing) if the string passed in is a magic short-hand form
531 * to name a branch.
532 */
533 static char *substitute_branch_name(const char **string, int *len)
534 {
535 struct strbuf buf = STRBUF_INIT;
536 int ret = interpret_branch_name(*string, *len, &buf, 0);
537
538 if (ret == *len) {
539 size_t size;
540 *string = strbuf_detach(&buf, &size);
541 *len = size;
542 return (char *)*string;
543 }
544
545 return NULL;
546 }
547
548 int dwim_ref(const char *str, int len, struct object_id *oid, char **ref)
549 {
550 char *last_branch = substitute_branch_name(&str, &len);
551 int refs_found = expand_ref(str, len, oid, ref);
552 free(last_branch);
553 return refs_found;
554 }
555
556 int expand_ref(const char *str, int len, struct object_id *oid, char **ref)
557 {
558 const char **p, *r;
559 int refs_found = 0;
560 struct strbuf fullref = STRBUF_INIT;
561
562 *ref = NULL;
563 for (p = ref_rev_parse_rules; *p; p++) {
564 struct object_id oid_from_ref;
565 struct object_id *this_result;
566 int flag;
567
568 this_result = refs_found ? &oid_from_ref : oid;
569 strbuf_reset(&fullref);
570 strbuf_addf(&fullref, *p, len, str);
571 r = resolve_ref_unsafe(fullref.buf, RESOLVE_REF_READING,
572 this_result, &flag);
573 if (r) {
574 if (!refs_found++)
575 *ref = xstrdup(r);
576 if (!warn_ambiguous_refs)
577 break;
578 } else if ((flag & REF_ISSYMREF) && strcmp(fullref.buf, "HEAD")) {
579 warning(_("ignoring dangling symref %s"), fullref.buf);
580 } else if ((flag & REF_ISBROKEN) && strchr(fullref.buf, '/')) {
581 warning(_("ignoring broken ref %s"), fullref.buf);
582 }
583 }
584 strbuf_release(&fullref);
585 return refs_found;
586 }
587
588 int dwim_log(const char *str, int len, struct object_id *oid, char **log)
589 {
590 char *last_branch = substitute_branch_name(&str, &len);
591 const char **p;
592 int logs_found = 0;
593 struct strbuf path = STRBUF_INIT;
594
595 *log = NULL;
596 for (p = ref_rev_parse_rules; *p; p++) {
597 struct object_id hash;
598 const char *ref, *it;
599
600 strbuf_reset(&path);
601 strbuf_addf(&path, *p, len, str);
602 ref = resolve_ref_unsafe(path.buf, RESOLVE_REF_READING,
603 &hash, NULL);
604 if (!ref)
605 continue;
606 if (reflog_exists(path.buf))
607 it = path.buf;
608 else if (strcmp(ref, path.buf) && reflog_exists(ref))
609 it = ref;
610 else
611 continue;
612 if (!logs_found++) {
613 *log = xstrdup(it);
614 oidcpy(oid, &hash);
615 }
616 if (!warn_ambiguous_refs)
617 break;
618 }
619 strbuf_release(&path);
620 free(last_branch);
621 return logs_found;
622 }
623
624 static int is_per_worktree_ref(const char *refname)
625 {
626 return !strcmp(refname, "HEAD") ||
627 starts_with(refname, "refs/bisect/") ||
628 starts_with(refname, "refs/rewritten/");
629 }
630
631 static int is_pseudoref_syntax(const char *refname)
632 {
633 const char *c;
634
635 for (c = refname; *c; c++) {
636 if (!isupper(*c) && *c != '-' && *c != '_')
637 return 0;
638 }
639
640 return 1;
641 }
642
643 enum ref_type ref_type(const char *refname)
644 {
645 if (is_per_worktree_ref(refname))
646 return REF_TYPE_PER_WORKTREE;
647 if (is_pseudoref_syntax(refname))
648 return REF_TYPE_PSEUDOREF;
649 return REF_TYPE_NORMAL;
650 }
651
652 long get_files_ref_lock_timeout_ms(void)
653 {
654 static int configured = 0;
655
656 /* The default timeout is 100 ms: */
657 static int timeout_ms = 100;
658
659 if (!configured) {
660 git_config_get_int("core.filesreflocktimeout", &timeout_ms);
661 configured = 1;
662 }
663
664 return timeout_ms;
665 }
666
667 static int write_pseudoref(const char *pseudoref, const struct object_id *oid,
668 const struct object_id *old_oid, struct strbuf *err)
669 {
670 const char *filename;
671 int fd;
672 struct lock_file lock = LOCK_INIT;
673 struct strbuf buf = STRBUF_INIT;
674 int ret = -1;
675
676 if (!oid)
677 return 0;
678
679 strbuf_addf(&buf, "%s\n", oid_to_hex(oid));
680
681 filename = git_path("%s", pseudoref);
682 fd = hold_lock_file_for_update_timeout(&lock, filename, 0,
683 get_files_ref_lock_timeout_ms());
684 if (fd < 0) {
685 strbuf_addf(err, _("could not open '%s' for writing: %s"),
686 filename, strerror(errno));
687 goto done;
688 }
689
690 if (old_oid) {
691 struct object_id actual_old_oid;
692
693 if (read_ref(pseudoref, &actual_old_oid)) {
694 if (!is_null_oid(old_oid)) {
695 strbuf_addf(err, _("could not read ref '%s'"),
696 pseudoref);
697 rollback_lock_file(&lock);
698 goto done;
699 }
700 } else if (is_null_oid(old_oid)) {
701 strbuf_addf(err, _("ref '%s' already exists"),
702 pseudoref);
703 rollback_lock_file(&lock);
704 goto done;
705 } else if (oidcmp(&actual_old_oid, old_oid)) {
706 strbuf_addf(err, _("unexpected object ID when writing '%s'"),
707 pseudoref);
708 rollback_lock_file(&lock);
709 goto done;
710 }
711 }
712
713 if (write_in_full(fd, buf.buf, buf.len) < 0) {
714 strbuf_addf(err, _("could not write to '%s'"), filename);
715 rollback_lock_file(&lock);
716 goto done;
717 }
718
719 commit_lock_file(&lock);
720 ret = 0;
721 done:
722 strbuf_release(&buf);
723 return ret;
724 }
725
726 static int delete_pseudoref(const char *pseudoref, const struct object_id *old_oid)
727 {
728 const char *filename;
729
730 filename = git_path("%s", pseudoref);
731
732 if (old_oid && !is_null_oid(old_oid)) {
733 struct lock_file lock = LOCK_INIT;
734 int fd;
735 struct object_id actual_old_oid;
736
737 fd = hold_lock_file_for_update_timeout(
738 &lock, filename, 0,
739 get_files_ref_lock_timeout_ms());
740 if (fd < 0) {
741 error_errno(_("could not open '%s' for writing"),
742 filename);
743 return -1;
744 }
745 if (read_ref(pseudoref, &actual_old_oid))
746 die(_("could not read ref '%s'"), pseudoref);
747 if (oidcmp(&actual_old_oid, old_oid)) {
748 error(_("unexpected object ID when deleting '%s'"),
749 pseudoref);
750 rollback_lock_file(&lock);
751 return -1;
752 }
753
754 unlink(filename);
755 rollback_lock_file(&lock);
756 } else {
757 unlink(filename);
758 }
759
760 return 0;
761 }
762
763 int refs_delete_ref(struct ref_store *refs, const char *msg,
764 const char *refname,
765 const struct object_id *old_oid,
766 unsigned int flags)
767 {
768 struct ref_transaction *transaction;
769 struct strbuf err = STRBUF_INIT;
770
771 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
772 assert(refs == get_main_ref_store(the_repository));
773 return delete_pseudoref(refname, old_oid);
774 }
775
776 transaction = ref_store_transaction_begin(refs, &err);
777 if (!transaction ||
778 ref_transaction_delete(transaction, refname, old_oid,
779 flags, msg, &err) ||
780 ref_transaction_commit(transaction, &err)) {
781 error("%s", err.buf);
782 ref_transaction_free(transaction);
783 strbuf_release(&err);
784 return 1;
785 }
786 ref_transaction_free(transaction);
787 strbuf_release(&err);
788 return 0;
789 }
790
791 int delete_ref(const char *msg, const char *refname,
792 const struct object_id *old_oid, unsigned int flags)
793 {
794 return refs_delete_ref(get_main_ref_store(the_repository), msg, refname,
795 old_oid, flags);
796 }
797
798 void copy_reflog_msg(struct strbuf *sb, const char *msg)
799 {
800 char c;
801 int wasspace = 1;
802
803 strbuf_addch(sb, '\t');
804 while ((c = *msg++)) {
805 if (wasspace && isspace(c))
806 continue;
807 wasspace = isspace(c);
808 if (wasspace)
809 c = ' ';
810 strbuf_addch(sb, c);
811 }
812 strbuf_rtrim(sb);
813 }
814
815 int should_autocreate_reflog(const char *refname)
816 {
817 switch (log_all_ref_updates) {
818 case LOG_REFS_ALWAYS:
819 return 1;
820 case LOG_REFS_NORMAL:
821 return starts_with(refname, "refs/heads/") ||
822 starts_with(refname, "refs/remotes/") ||
823 starts_with(refname, "refs/notes/") ||
824 !strcmp(refname, "HEAD");
825 default:
826 return 0;
827 }
828 }
829
830 int is_branch(const char *refname)
831 {
832 return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
833 }
834
835 struct read_ref_at_cb {
836 const char *refname;
837 timestamp_t at_time;
838 int cnt;
839 int reccnt;
840 struct object_id *oid;
841 int found_it;
842
843 struct object_id ooid;
844 struct object_id noid;
845 int tz;
846 timestamp_t date;
847 char **msg;
848 timestamp_t *cutoff_time;
849 int *cutoff_tz;
850 int *cutoff_cnt;
851 };
852
853 static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
854 const char *email, timestamp_t timestamp, int tz,
855 const char *message, void *cb_data)
856 {
857 struct read_ref_at_cb *cb = cb_data;
858
859 cb->reccnt++;
860 cb->tz = tz;
861 cb->date = timestamp;
862
863 if (timestamp <= cb->at_time || cb->cnt == 0) {
864 if (cb->msg)
865 *cb->msg = xstrdup(message);
866 if (cb->cutoff_time)
867 *cb->cutoff_time = timestamp;
868 if (cb->cutoff_tz)
869 *cb->cutoff_tz = tz;
870 if (cb->cutoff_cnt)
871 *cb->cutoff_cnt = cb->reccnt - 1;
872 /*
873 * we have not yet updated cb->[n|o]oid so they still
874 * hold the values for the previous record.
875 */
876 if (!is_null_oid(&cb->ooid)) {
877 oidcpy(cb->oid, noid);
878 if (oidcmp(&cb->ooid, noid))
879 warning(_("log for ref %s has gap after %s"),
880 cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
881 }
882 else if (cb->date == cb->at_time)
883 oidcpy(cb->oid, noid);
884 else if (oidcmp(noid, cb->oid))
885 warning(_("log for ref %s unexpectedly ended on %s"),
886 cb->refname, show_date(cb->date, cb->tz,
887 DATE_MODE(RFC2822)));
888 oidcpy(&cb->ooid, ooid);
889 oidcpy(&cb->noid, noid);
890 cb->found_it = 1;
891 return 1;
892 }
893 oidcpy(&cb->ooid, ooid);
894 oidcpy(&cb->noid, noid);
895 if (cb->cnt > 0)
896 cb->cnt--;
897 return 0;
898 }
899
900 static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
901 const char *email, timestamp_t timestamp,
902 int tz, const char *message, void *cb_data)
903 {
904 struct read_ref_at_cb *cb = cb_data;
905
906 if (cb->msg)
907 *cb->msg = xstrdup(message);
908 if (cb->cutoff_time)
909 *cb->cutoff_time = timestamp;
910 if (cb->cutoff_tz)
911 *cb->cutoff_tz = tz;
912 if (cb->cutoff_cnt)
913 *cb->cutoff_cnt = cb->reccnt;
914 oidcpy(cb->oid, ooid);
915 if (is_null_oid(cb->oid))
916 oidcpy(cb->oid, noid);
917 /* We just want the first entry */
918 return 1;
919 }
920
921 int read_ref_at(const char *refname, unsigned int flags, timestamp_t at_time, int cnt,
922 struct object_id *oid, char **msg,
923 timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
924 {
925 struct read_ref_at_cb cb;
926
927 memset(&cb, 0, sizeof(cb));
928 cb.refname = refname;
929 cb.at_time = at_time;
930 cb.cnt = cnt;
931 cb.msg = msg;
932 cb.cutoff_time = cutoff_time;
933 cb.cutoff_tz = cutoff_tz;
934 cb.cutoff_cnt = cutoff_cnt;
935 cb.oid = oid;
936
937 for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
938
939 if (!cb.reccnt) {
940 if (flags & GET_OID_QUIETLY)
941 exit(128);
942 else
943 die(_("log for %s is empty"), refname);
944 }
945 if (cb.found_it)
946 return 0;
947
948 for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
949
950 return 1;
951 }
952
953 struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs,
954 struct strbuf *err)
955 {
956 struct ref_transaction *tr;
957 assert(err);
958
959 tr = xcalloc(1, sizeof(struct ref_transaction));
960 tr->ref_store = refs;
961 return tr;
962 }
963
964 struct ref_transaction *ref_transaction_begin(struct strbuf *err)
965 {
966 return ref_store_transaction_begin(get_main_ref_store(the_repository), err);
967 }
968
969 void ref_transaction_free(struct ref_transaction *transaction)
970 {
971 size_t i;
972
973 if (!transaction)
974 return;
975
976 switch (transaction->state) {
977 case REF_TRANSACTION_OPEN:
978 case REF_TRANSACTION_CLOSED:
979 /* OK */
980 break;
981 case REF_TRANSACTION_PREPARED:
982 BUG("free called on a prepared reference transaction");
983 break;
984 default:
985 BUG("unexpected reference transaction state");
986 break;
987 }
988
989 for (i = 0; i < transaction->nr; i++) {
990 free(transaction->updates[i]->msg);
991 free(transaction->updates[i]);
992 }
993 free(transaction->updates);
994 free(transaction);
995 }
996
997 struct ref_update *ref_transaction_add_update(
998 struct ref_transaction *transaction,
999 const char *refname, unsigned int flags,
1000 const struct object_id *new_oid,
1001 const struct object_id *old_oid,
1002 const char *msg)
1003 {
1004 struct ref_update *update;
1005
1006 if (transaction->state != REF_TRANSACTION_OPEN)
1007 BUG("update called for transaction that is not open");
1008
1009 FLEX_ALLOC_STR(update, refname, refname);
1010 ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
1011 transaction->updates[transaction->nr++] = update;
1012
1013 update->flags = flags;
1014
1015 if (flags & REF_HAVE_NEW)
1016 oidcpy(&update->new_oid, new_oid);
1017 if (flags & REF_HAVE_OLD)
1018 oidcpy(&update->old_oid, old_oid);
1019 update->msg = xstrdup_or_null(msg);
1020 return update;
1021 }
1022
1023 int ref_transaction_update(struct ref_transaction *transaction,
1024 const char *refname,
1025 const struct object_id *new_oid,
1026 const struct object_id *old_oid,
1027 unsigned int flags, const char *msg,
1028 struct strbuf *err)
1029 {
1030 assert(err);
1031
1032 if ((new_oid && !is_null_oid(new_oid)) ?
1033 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
1034 !refname_is_safe(refname)) {
1035 strbuf_addf(err, _("refusing to update ref with bad name '%s'"),
1036 refname);
1037 return -1;
1038 }
1039
1040 if (flags & ~REF_TRANSACTION_UPDATE_ALLOWED_FLAGS)
1041 BUG("illegal flags 0x%x passed to ref_transaction_update()", flags);
1042
1043 flags |= (new_oid ? REF_HAVE_NEW : 0) | (old_oid ? REF_HAVE_OLD : 0);
1044
1045 ref_transaction_add_update(transaction, refname, flags,
1046 new_oid, old_oid, msg);
1047 return 0;
1048 }
1049
1050 int ref_transaction_create(struct ref_transaction *transaction,
1051 const char *refname,
1052 const struct object_id *new_oid,
1053 unsigned int flags, const char *msg,
1054 struct strbuf *err)
1055 {
1056 if (!new_oid || is_null_oid(new_oid))
1057 BUG("create called without valid new_oid");
1058 return ref_transaction_update(transaction, refname, new_oid,
1059 &null_oid, flags, msg, err);
1060 }
1061
1062 int ref_transaction_delete(struct ref_transaction *transaction,
1063 const char *refname,
1064 const struct object_id *old_oid,
1065 unsigned int flags, const char *msg,
1066 struct strbuf *err)
1067 {
1068 if (old_oid && is_null_oid(old_oid))
1069 BUG("delete called with old_oid set to zeros");
1070 return ref_transaction_update(transaction, refname,
1071 &null_oid, old_oid,
1072 flags, msg, err);
1073 }
1074
1075 int ref_transaction_verify(struct ref_transaction *transaction,
1076 const char *refname,
1077 const struct object_id *old_oid,
1078 unsigned int flags,
1079 struct strbuf *err)
1080 {
1081 if (!old_oid)
1082 BUG("verify called with old_oid set to NULL");
1083 return ref_transaction_update(transaction, refname,
1084 NULL, old_oid,
1085 flags, NULL, err);
1086 }
1087
1088 int refs_update_ref(struct ref_store *refs, const char *msg,
1089 const char *refname, const struct object_id *new_oid,
1090 const struct object_id *old_oid, unsigned int flags,
1091 enum action_on_err onerr)
1092 {
1093 struct ref_transaction *t = NULL;
1094 struct strbuf err = STRBUF_INIT;
1095 int ret = 0;
1096
1097 if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
1098 assert(refs == get_main_ref_store(the_repository));
1099 ret = write_pseudoref(refname, new_oid, old_oid, &err);
1100 } else {
1101 t = ref_store_transaction_begin(refs, &err);
1102 if (!t ||
1103 ref_transaction_update(t, refname, new_oid, old_oid,
1104 flags, msg, &err) ||
1105 ref_transaction_commit(t, &err)) {
1106 ret = 1;
1107 ref_transaction_free(t);
1108 }
1109 }
1110 if (ret) {
1111 const char *str = _("update_ref failed for ref '%s': %s");
1112
1113 switch (onerr) {
1114 case UPDATE_REFS_MSG_ON_ERR:
1115 error(str, refname, err.buf);
1116 break;
1117 case UPDATE_REFS_DIE_ON_ERR:
1118 die(str, refname, err.buf);
1119 break;
1120 case UPDATE_REFS_QUIET_ON_ERR:
1121 break;
1122 }
1123 strbuf_release(&err);
1124 return 1;
1125 }
1126 strbuf_release(&err);
1127 if (t)
1128 ref_transaction_free(t);
1129 return 0;
1130 }
1131
1132 int update_ref(const char *msg, const char *refname,
1133 const struct object_id *new_oid,
1134 const struct object_id *old_oid,
1135 unsigned int flags, enum action_on_err onerr)
1136 {
1137 return refs_update_ref(get_main_ref_store(the_repository), msg, refname, new_oid,
1138 old_oid, flags, onerr);
1139 }
1140
1141 char *shorten_unambiguous_ref(const char *refname, int strict)
1142 {
1143 int i;
1144 static char **scanf_fmts;
1145 static int nr_rules;
1146 char *short_name;
1147 struct strbuf resolved_buf = STRBUF_INIT;
1148
1149 if (!nr_rules) {
1150 /*
1151 * Pre-generate scanf formats from ref_rev_parse_rules[].
1152 * Generate a format suitable for scanf from a
1153 * ref_rev_parse_rules rule by interpolating "%s" at the
1154 * location of the "%.*s".
1155 */
1156 size_t total_len = 0;
1157 size_t offset = 0;
1158
1159 /* the rule list is NULL terminated, count them first */
1160 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
1161 /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
1162 total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
1163
1164 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
1165
1166 offset = 0;
1167 for (i = 0; i < nr_rules; i++) {
1168 assert(offset < total_len);
1169 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
1170 offset += xsnprintf(scanf_fmts[i], total_len - offset,
1171 ref_rev_parse_rules[i], 2, "%s") + 1;
1172 }
1173 }
1174
1175 /* bail out if there are no rules */
1176 if (!nr_rules)
1177 return xstrdup(refname);
1178
1179 /* buffer for scanf result, at most refname must fit */
1180 short_name = xstrdup(refname);
1181
1182 /* skip first rule, it will always match */
1183 for (i = nr_rules - 1; i > 0 ; --i) {
1184 int j;
1185 int rules_to_fail = i;
1186 int short_name_len;
1187
1188 if (1 != sscanf(refname, scanf_fmts[i], short_name))
1189 continue;
1190
1191 short_name_len = strlen(short_name);
1192
1193 /*
1194 * in strict mode, all (except the matched one) rules
1195 * must fail to resolve to a valid non-ambiguous ref
1196 */
1197 if (strict)
1198 rules_to_fail = nr_rules;
1199
1200 /*
1201 * check if the short name resolves to a valid ref,
1202 * but use only rules prior to the matched one
1203 */
1204 for (j = 0; j < rules_to_fail; j++) {
1205 const char *rule = ref_rev_parse_rules[j];
1206
1207 /* skip matched rule */
1208 if (i == j)
1209 continue;
1210
1211 /*
1212 * the short name is ambiguous, if it resolves
1213 * (with this previous rule) to a valid ref
1214 * read_ref() returns 0 on success
1215 */
1216 strbuf_reset(&resolved_buf);
1217 strbuf_addf(&resolved_buf, rule,
1218 short_name_len, short_name);
1219 if (ref_exists(resolved_buf.buf))
1220 break;
1221 }
1222
1223 /*
1224 * short name is non-ambiguous if all previous rules
1225 * haven't resolved to a valid ref
1226 */
1227 if (j == rules_to_fail) {
1228 strbuf_release(&resolved_buf);
1229 return short_name;
1230 }
1231 }
1232
1233 strbuf_release(&resolved_buf);
1234 free(short_name);
1235 return xstrdup(refname);
1236 }
1237
1238 static struct string_list *hide_refs;
1239
1240 int parse_hide_refs_config(const char *var, const char *value, const char *section)
1241 {
1242 const char *key;
1243 if (!strcmp("transfer.hiderefs", var) ||
1244 (!parse_config_key(var, section, NULL, NULL, &key) &&
1245 !strcmp(key, "hiderefs"))) {
1246 char *ref;
1247 int len;
1248
1249 if (!value)
1250 return config_error_nonbool(var);
1251 ref = xstrdup(value);
1252 len = strlen(ref);
1253 while (len && ref[len - 1] == '/')
1254 ref[--len] = '\0';
1255 if (!hide_refs) {
1256 hide_refs = xcalloc(1, sizeof(*hide_refs));
1257 hide_refs->strdup_strings = 1;
1258 }
1259 string_list_append(hide_refs, ref);
1260 }
1261 return 0;
1262 }
1263
1264 int ref_is_hidden(const char *refname, const char *refname_full)
1265 {
1266 int i;
1267
1268 if (!hide_refs)
1269 return 0;
1270 for (i = hide_refs->nr - 1; i >= 0; i--) {
1271 const char *match = hide_refs->items[i].string;
1272 const char *subject;
1273 int neg = 0;
1274 const char *p;
1275
1276 if (*match == '!') {
1277 neg = 1;
1278 match++;
1279 }
1280
1281 if (*match == '^') {
1282 subject = refname_full;
1283 match++;
1284 } else {
1285 subject = refname;
1286 }
1287
1288 /* refname can be NULL when namespaces are used. */
1289 if (subject &&
1290 skip_prefix(subject, match, &p) &&
1291 (!*p || *p == '/'))
1292 return !neg;
1293 }
1294 return 0;
1295 }
1296
1297 const char *find_descendant_ref(const char *dirname,
1298 const struct string_list *extras,
1299 const struct string_list *skip)
1300 {
1301 int pos;
1302
1303 if (!extras)
1304 return NULL;
1305
1306 /*
1307 * Look at the place where dirname would be inserted into
1308 * extras. If there is an entry at that position that starts
1309 * with dirname (remember, dirname includes the trailing
1310 * slash) and is not in skip, then we have a conflict.
1311 */
1312 for (pos = string_list_find_insert_index(extras, dirname, 0);
1313 pos < extras->nr; pos++) {
1314 const char *extra_refname = extras->items[pos].string;
1315
1316 if (!starts_with(extra_refname, dirname))
1317 break;
1318
1319 if (!skip || !string_list_has_string(skip, extra_refname))
1320 return extra_refname;
1321 }
1322 return NULL;
1323 }
1324
1325 int refs_rename_ref_available(struct ref_store *refs,
1326 const char *old_refname,
1327 const char *new_refname)
1328 {
1329 struct string_list skip = STRING_LIST_INIT_NODUP;
1330 struct strbuf err = STRBUF_INIT;
1331 int ok;
1332
1333 string_list_insert(&skip, old_refname);
1334 ok = !refs_verify_refname_available(refs, new_refname,
1335 NULL, &skip, &err);
1336 if (!ok)
1337 error("%s", err.buf);
1338
1339 string_list_clear(&skip, 0);
1340 strbuf_release(&err);
1341 return ok;
1342 }
1343
1344 int refs_head_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1345 {
1346 struct object_id oid;
1347 int flag;
1348
1349 if (!refs_read_ref_full(refs, "HEAD", RESOLVE_REF_READING,
1350 &oid, &flag))
1351 return fn("HEAD", &oid, flag, cb_data);
1352
1353 return 0;
1354 }
1355
1356 int head_ref(each_ref_fn fn, void *cb_data)
1357 {
1358 return refs_head_ref(get_main_ref_store(the_repository), fn, cb_data);
1359 }
1360
1361 struct ref_iterator *refs_ref_iterator_begin(
1362 struct ref_store *refs,
1363 const char *prefix, int trim, int flags)
1364 {
1365 struct ref_iterator *iter;
1366
1367 if (ref_paranoia < 0)
1368 ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
1369 if (ref_paranoia)
1370 flags |= DO_FOR_EACH_INCLUDE_BROKEN;
1371
1372 iter = refs->be->iterator_begin(refs, prefix, flags);
1373
1374 /*
1375 * `iterator_begin()` already takes care of prefix, but we
1376 * might need to do some trimming:
1377 */
1378 if (trim)
1379 iter = prefix_ref_iterator_begin(iter, "", trim);
1380
1381 /* Sanity check for subclasses: */
1382 if (!iter->ordered)
1383 BUG("reference iterator is not ordered");
1384
1385 return iter;
1386 }
1387
1388 /*
1389 * Call fn for each reference in the specified submodule for which the
1390 * refname begins with prefix. If trim is non-zero, then trim that
1391 * many characters off the beginning of each refname before passing
1392 * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1393 * include broken references in the iteration. If fn ever returns a
1394 * non-zero value, stop the iteration and return that value;
1395 * otherwise, return 0.
1396 */
1397 static int do_for_each_ref(struct ref_store *refs, const char *prefix,
1398 each_ref_fn fn, int trim, int flags, void *cb_data)
1399 {
1400 struct ref_iterator *iter;
1401
1402 if (!refs)
1403 return 0;
1404
1405 iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1406
1407 return do_for_each_ref_iterator(iter, fn, cb_data);
1408 }
1409
1410 int refs_for_each_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1411 {
1412 return do_for_each_ref(refs, "", fn, 0, 0, cb_data);
1413 }
1414
1415 int for_each_ref(each_ref_fn fn, void *cb_data)
1416 {
1417 return refs_for_each_ref(get_main_ref_store(the_repository), fn, cb_data);
1418 }
1419
1420 int refs_for_each_ref_in(struct ref_store *refs, const char *prefix,
1421 each_ref_fn fn, void *cb_data)
1422 {
1423 return do_for_each_ref(refs, prefix, fn, strlen(prefix), 0, cb_data);
1424 }
1425
1426 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1427 {
1428 return refs_for_each_ref_in(get_main_ref_store(the_repository), prefix, fn, cb_data);
1429 }
1430
1431 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1432 {
1433 unsigned int flag = 0;
1434
1435 if (broken)
1436 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1437 return do_for_each_ref(get_main_ref_store(the_repository),
1438 prefix, fn, 0, flag, cb_data);
1439 }
1440
1441 int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix,
1442 each_ref_fn fn, void *cb_data,
1443 unsigned int broken)
1444 {
1445 unsigned int flag = 0;
1446
1447 if (broken)
1448 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1449 return do_for_each_ref(refs, prefix, fn, 0, flag, cb_data);
1450 }
1451
1452 int for_each_replace_ref(struct repository *r, each_ref_fn fn, void *cb_data)
1453 {
1454 return do_for_each_ref(get_main_ref_store(r),
1455 git_replace_ref_base, fn,
1456 strlen(git_replace_ref_base),
1457 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1458 }
1459
1460 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1461 {
1462 struct strbuf buf = STRBUF_INIT;
1463 int ret;
1464 strbuf_addf(&buf, "%srefs/", get_git_namespace());
1465 ret = do_for_each_ref(get_main_ref_store(the_repository),
1466 buf.buf, fn, 0, 0, cb_data);
1467 strbuf_release(&buf);
1468 return ret;
1469 }
1470
1471 int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1472 {
1473 return do_for_each_ref(refs, "", fn, 0,
1474 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1475 }
1476
1477 int for_each_rawref(each_ref_fn fn, void *cb_data)
1478 {
1479 return refs_for_each_rawref(get_main_ref_store(the_repository), fn, cb_data);
1480 }
1481
1482 int refs_read_raw_ref(struct ref_store *ref_store,
1483 const char *refname, struct object_id *oid,
1484 struct strbuf *referent, unsigned int *type)
1485 {
1486 return ref_store->be->read_raw_ref(ref_store, refname, oid, referent, type);
1487 }
1488
1489 /* This function needs to return a meaningful errno on failure */
1490 const char *refs_resolve_ref_unsafe(struct ref_store *refs,
1491 const char *refname,
1492 int resolve_flags,
1493 struct object_id *oid, int *flags)
1494 {
1495 static struct strbuf sb_refname = STRBUF_INIT;
1496 struct object_id unused_oid;
1497 int unused_flags;
1498 int symref_count;
1499
1500 if (!oid)
1501 oid = &unused_oid;
1502 if (!flags)
1503 flags = &unused_flags;
1504
1505 *flags = 0;
1506
1507 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1508 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1509 !refname_is_safe(refname)) {
1510 errno = EINVAL;
1511 return NULL;
1512 }
1513
1514 /*
1515 * dwim_ref() uses REF_ISBROKEN to distinguish between
1516 * missing refs and refs that were present but invalid,
1517 * to complain about the latter to stderr.
1518 *
1519 * We don't know whether the ref exists, so don't set
1520 * REF_ISBROKEN yet.
1521 */
1522 *flags |= REF_BAD_NAME;
1523 }
1524
1525 for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1526 unsigned int read_flags = 0;
1527
1528 if (refs_read_raw_ref(refs, refname,
1529 oid, &sb_refname, &read_flags)) {
1530 *flags |= read_flags;
1531
1532 /* In reading mode, refs must eventually resolve */
1533 if (resolve_flags & RESOLVE_REF_READING)
1534 return NULL;
1535
1536 /*
1537 * Otherwise a missing ref is OK. But the files backend
1538 * may show errors besides ENOENT if there are
1539 * similarly-named refs.
1540 */
1541 if (errno != ENOENT &&
1542 errno != EISDIR &&
1543 errno != ENOTDIR)
1544 return NULL;
1545
1546 oidclr(oid);
1547 if (*flags & REF_BAD_NAME)
1548 *flags |= REF_ISBROKEN;
1549 return refname;
1550 }
1551
1552 *flags |= read_flags;
1553
1554 if (!(read_flags & REF_ISSYMREF)) {
1555 if (*flags & REF_BAD_NAME) {
1556 oidclr(oid);
1557 *flags |= REF_ISBROKEN;
1558 }
1559 return refname;
1560 }
1561
1562 refname = sb_refname.buf;
1563 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1564 oidclr(oid);
1565 return refname;
1566 }
1567 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1568 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1569 !refname_is_safe(refname)) {
1570 errno = EINVAL;
1571 return NULL;
1572 }
1573
1574 *flags |= REF_ISBROKEN | REF_BAD_NAME;
1575 }
1576 }
1577
1578 errno = ELOOP;
1579 return NULL;
1580 }
1581
1582 /* backend functions */
1583 int refs_init_db(struct strbuf *err)
1584 {
1585 struct ref_store *refs = get_main_ref_store(the_repository);
1586
1587 return refs->be->init_db(refs, err);
1588 }
1589
1590 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1591 struct object_id *oid, int *flags)
1592 {
1593 return refs_resolve_ref_unsafe(get_main_ref_store(the_repository), refname,
1594 resolve_flags, oid, flags);
1595 }
1596
1597 int resolve_gitlink_ref(const char *submodule, const char *refname,
1598 struct object_id *oid)
1599 {
1600 struct ref_store *refs;
1601 int flags;
1602
1603 refs = get_submodule_ref_store(submodule);
1604
1605 if (!refs)
1606 return -1;
1607
1608 if (!refs_resolve_ref_unsafe(refs, refname, 0, oid, &flags) ||
1609 is_null_oid(oid))
1610 return -1;
1611 return 0;
1612 }
1613
1614 struct ref_store_hash_entry
1615 {
1616 struct hashmap_entry ent; /* must be the first member! */
1617
1618 struct ref_store *refs;
1619
1620 /* NUL-terminated identifier of the ref store: */
1621 char name[FLEX_ARRAY];
1622 };
1623
1624 static int ref_store_hash_cmp(const void *unused_cmp_data,
1625 const void *entry, const void *entry_or_key,
1626 const void *keydata)
1627 {
1628 const struct ref_store_hash_entry *e1 = entry, *e2 = entry_or_key;
1629 const char *name = keydata ? keydata : e2->name;
1630
1631 return strcmp(e1->name, name);
1632 }
1633
1634 static struct ref_store_hash_entry *alloc_ref_store_hash_entry(
1635 const char *name, struct ref_store *refs)
1636 {
1637 struct ref_store_hash_entry *entry;
1638
1639 FLEX_ALLOC_STR(entry, name, name);
1640 hashmap_entry_init(entry, strhash(name));
1641 entry->refs = refs;
1642 return entry;
1643 }
1644
1645 /* A hashmap of ref_stores, stored by submodule name: */
1646 static struct hashmap submodule_ref_stores;
1647
1648 /* A hashmap of ref_stores, stored by worktree id: */
1649 static struct hashmap worktree_ref_stores;
1650
1651 /*
1652 * Look up a ref store by name. If that ref_store hasn't been
1653 * registered yet, return NULL.
1654 */
1655 static struct ref_store *lookup_ref_store_map(struct hashmap *map,
1656 const char *name)
1657 {
1658 struct ref_store_hash_entry *entry;
1659
1660 if (!map->tablesize)
1661 /* It's initialized on demand in register_ref_store(). */
1662 return NULL;
1663
1664 entry = hashmap_get_from_hash(map, strhash(name), name);
1665 return entry ? entry->refs : NULL;
1666 }
1667
1668 /*
1669 * Create, record, and return a ref_store instance for the specified
1670 * gitdir.
1671 */
1672 static struct ref_store *ref_store_init(const char *gitdir,
1673 unsigned int flags)
1674 {
1675 const char *be_name = "files";
1676 struct ref_storage_be *be = find_ref_storage_backend(be_name);
1677 struct ref_store *refs;
1678
1679 if (!be)
1680 BUG("reference backend %s is unknown", be_name);
1681
1682 refs = be->init(gitdir, flags);
1683 return refs;
1684 }
1685
1686 struct ref_store *get_main_ref_store(struct repository *r)
1687 {
1688 if (r->refs)
1689 return r->refs;
1690
1691 if (!r->gitdir)
1692 BUG("attempting to get main_ref_store outside of repository");
1693
1694 r->refs = ref_store_init(r->gitdir, REF_STORE_ALL_CAPS);
1695 return r->refs;
1696 }
1697
1698 /*
1699 * Associate a ref store with a name. It is a fatal error to call this
1700 * function twice for the same name.
1701 */
1702 static void register_ref_store_map(struct hashmap *map,
1703 const char *type,
1704 struct ref_store *refs,
1705 const char *name)
1706 {
1707 if (!map->tablesize)
1708 hashmap_init(map, ref_store_hash_cmp, NULL, 0);
1709
1710 if (hashmap_put(map, alloc_ref_store_hash_entry(name, refs)))
1711 BUG("%s ref_store '%s' initialized twice", type, name);
1712 }
1713
1714 struct ref_store *get_submodule_ref_store(const char *submodule)
1715 {
1716 struct strbuf submodule_sb = STRBUF_INIT;
1717 struct ref_store *refs;
1718 char *to_free = NULL;
1719 size_t len;
1720
1721 if (!submodule)
1722 return NULL;
1723
1724 len = strlen(submodule);
1725 while (len && is_dir_sep(submodule[len - 1]))
1726 len--;
1727 if (!len)
1728 return NULL;
1729
1730 if (submodule[len])
1731 /* We need to strip off one or more trailing slashes */
1732 submodule = to_free = xmemdupz(submodule, len);
1733
1734 refs = lookup_ref_store_map(&submodule_ref_stores, submodule);
1735 if (refs)
1736 goto done;
1737
1738 strbuf_addstr(&submodule_sb, submodule);
1739 if (!is_nonbare_repository_dir(&submodule_sb))
1740 goto done;
1741
1742 if (submodule_to_gitdir(&submodule_sb, submodule))
1743 goto done;
1744
1745 /* assume that add_submodule_odb() has been called */
1746 refs = ref_store_init(submodule_sb.buf,
1747 REF_STORE_READ | REF_STORE_ODB);
1748 register_ref_store_map(&submodule_ref_stores, "submodule",
1749 refs, submodule);
1750
1751 done:
1752 strbuf_release(&submodule_sb);
1753 free(to_free);
1754
1755 return refs;
1756 }
1757
1758 struct ref_store *get_worktree_ref_store(const struct worktree *wt)
1759 {
1760 struct ref_store *refs;
1761 const char *id;
1762
1763 if (wt->is_current)
1764 return get_main_ref_store(the_repository);
1765
1766 id = wt->id ? wt->id : "/";
1767 refs = lookup_ref_store_map(&worktree_ref_stores, id);
1768 if (refs)
1769 return refs;
1770
1771 if (wt->id)
1772 refs = ref_store_init(git_common_path("worktrees/%s", wt->id),
1773 REF_STORE_ALL_CAPS);
1774 else
1775 refs = ref_store_init(get_git_common_dir(),
1776 REF_STORE_ALL_CAPS);
1777
1778 if (refs)
1779 register_ref_store_map(&worktree_ref_stores, "worktree",
1780 refs, id);
1781 return refs;
1782 }
1783
1784 void base_ref_store_init(struct ref_store *refs,
1785 const struct ref_storage_be *be)
1786 {
1787 refs->be = be;
1788 }
1789
1790 /* backend functions */
1791 int refs_pack_refs(struct ref_store *refs, unsigned int flags)
1792 {
1793 return refs->be->pack_refs(refs, flags);
1794 }
1795
1796 int refs_peel_ref(struct ref_store *refs, const char *refname,
1797 struct object_id *oid)
1798 {
1799 int flag;
1800 struct object_id base;
1801
1802 if (current_ref_iter && current_ref_iter->refname == refname) {
1803 struct object_id peeled;
1804
1805 if (ref_iterator_peel(current_ref_iter, &peeled))
1806 return -1;
1807 oidcpy(oid, &peeled);
1808 return 0;
1809 }
1810
1811 if (refs_read_ref_full(refs, refname,
1812 RESOLVE_REF_READING, &base, &flag))
1813 return -1;
1814
1815 return peel_object(&base, oid);
1816 }
1817
1818 int peel_ref(const char *refname, struct object_id *oid)
1819 {
1820 return refs_peel_ref(get_main_ref_store(the_repository), refname, oid);
1821 }
1822
1823 int refs_create_symref(struct ref_store *refs,
1824 const char *ref_target,
1825 const char *refs_heads_master,
1826 const char *logmsg)
1827 {
1828 return refs->be->create_symref(refs, ref_target,
1829 refs_heads_master,
1830 logmsg);
1831 }
1832
1833 int create_symref(const char *ref_target, const char *refs_heads_master,
1834 const char *logmsg)
1835 {
1836 return refs_create_symref(get_main_ref_store(the_repository), ref_target,
1837 refs_heads_master, logmsg);
1838 }
1839
1840 int ref_update_reject_duplicates(struct string_list *refnames,
1841 struct strbuf *err)
1842 {
1843 size_t i, n = refnames->nr;
1844
1845 assert(err);
1846
1847 for (i = 1; i < n; i++) {
1848 int cmp = strcmp(refnames->items[i - 1].string,
1849 refnames->items[i].string);
1850
1851 if (!cmp) {
1852 strbuf_addf(err,
1853 _("multiple updates for ref '%s' not allowed"),
1854 refnames->items[i].string);
1855 return 1;
1856 } else if (cmp > 0) {
1857 BUG("ref_update_reject_duplicates() received unsorted list");
1858 }
1859 }
1860 return 0;
1861 }
1862
1863 int ref_transaction_prepare(struct ref_transaction *transaction,
1864 struct strbuf *err)
1865 {
1866 struct ref_store *refs = transaction->ref_store;
1867
1868 switch (transaction->state) {
1869 case REF_TRANSACTION_OPEN:
1870 /* Good. */
1871 break;
1872 case REF_TRANSACTION_PREPARED:
1873 BUG("prepare called twice on reference transaction");
1874 break;
1875 case REF_TRANSACTION_CLOSED:
1876 BUG("prepare called on a closed reference transaction");
1877 break;
1878 default:
1879 BUG("unexpected reference transaction state");
1880 break;
1881 }
1882
1883 if (getenv(GIT_QUARANTINE_ENVIRONMENT)) {
1884 strbuf_addstr(err,
1885 _("ref updates forbidden inside quarantine environment"));
1886 return -1;
1887 }
1888
1889 return refs->be->transaction_prepare(refs, transaction, err);
1890 }
1891
1892 int ref_transaction_abort(struct ref_transaction *transaction,
1893 struct strbuf *err)
1894 {
1895 struct ref_store *refs = transaction->ref_store;
1896 int ret = 0;
1897
1898 switch (transaction->state) {
1899 case REF_TRANSACTION_OPEN:
1900 /* No need to abort explicitly. */
1901 break;
1902 case REF_TRANSACTION_PREPARED:
1903 ret = refs->be->transaction_abort(refs, transaction, err);
1904 break;
1905 case REF_TRANSACTION_CLOSED:
1906 BUG("abort called on a closed reference transaction");
1907 break;
1908 default:
1909 BUG("unexpected reference transaction state");
1910 break;
1911 }
1912
1913 ref_transaction_free(transaction);
1914 return ret;
1915 }
1916
1917 int ref_transaction_commit(struct ref_transaction *transaction,
1918 struct strbuf *err)
1919 {
1920 struct ref_store *refs = transaction->ref_store;
1921 int ret;
1922
1923 switch (transaction->state) {
1924 case REF_TRANSACTION_OPEN:
1925 /* Need to prepare first. */
1926 ret = ref_transaction_prepare(transaction, err);
1927 if (ret)
1928 return ret;
1929 break;
1930 case REF_TRANSACTION_PREPARED:
1931 /* Fall through to finish. */
1932 break;
1933 case REF_TRANSACTION_CLOSED:
1934 BUG("commit called on a closed reference transaction");
1935 break;
1936 default:
1937 BUG("unexpected reference transaction state");
1938 break;
1939 }
1940
1941 return refs->be->transaction_finish(refs, transaction, err);
1942 }
1943
1944 int refs_verify_refname_available(struct ref_store *refs,
1945 const char *refname,
1946 const struct string_list *extras,
1947 const struct string_list *skip,
1948 struct strbuf *err)
1949 {
1950 const char *slash;
1951 const char *extra_refname;
1952 struct strbuf dirname = STRBUF_INIT;
1953 struct strbuf referent = STRBUF_INIT;
1954 struct object_id oid;
1955 unsigned int type;
1956 struct ref_iterator *iter;
1957 int ok;
1958 int ret = -1;
1959
1960 /*
1961 * For the sake of comments in this function, suppose that
1962 * refname is "refs/foo/bar".
1963 */
1964
1965 assert(err);
1966
1967 strbuf_grow(&dirname, strlen(refname) + 1);
1968 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
1969 /* Expand dirname to the new prefix, not including the trailing slash: */
1970 strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
1971
1972 /*
1973 * We are still at a leading dir of the refname (e.g.,
1974 * "refs/foo"; if there is a reference with that name,
1975 * it is a conflict, *unless* it is in skip.
1976 */
1977 if (skip && string_list_has_string(skip, dirname.buf))
1978 continue;
1979
1980 if (!refs_read_raw_ref(refs, dirname.buf, &oid, &referent, &type)) {
1981 strbuf_addf(err, _("'%s' exists; cannot create '%s'"),
1982 dirname.buf, refname);
1983 goto cleanup;
1984 }
1985
1986 if (extras && string_list_has_string(extras, dirname.buf)) {
1987 strbuf_addf(err, _("cannot process '%s' and '%s' at the same time"),
1988 refname, dirname.buf);
1989 goto cleanup;
1990 }
1991 }
1992
1993 /*
1994 * We are at the leaf of our refname (e.g., "refs/foo/bar").
1995 * There is no point in searching for a reference with that
1996 * name, because a refname isn't considered to conflict with
1997 * itself. But we still need to check for references whose
1998 * names are in the "refs/foo/bar/" namespace, because they
1999 * *do* conflict.
2000 */
2001 strbuf_addstr(&dirname, refname + dirname.len);
2002 strbuf_addch(&dirname, '/');
2003
2004 iter = refs_ref_iterator_begin(refs, dirname.buf, 0,
2005 DO_FOR_EACH_INCLUDE_BROKEN);
2006 while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
2007 if (skip &&
2008 string_list_has_string(skip, iter->refname))
2009 continue;
2010
2011 strbuf_addf(err, _("'%s' exists; cannot create '%s'"),
2012 iter->refname, refname);
2013 ref_iterator_abort(iter);
2014 goto cleanup;
2015 }
2016
2017 if (ok != ITER_DONE)
2018 BUG("error while iterating over references");
2019
2020 extra_refname = find_descendant_ref(dirname.buf, extras, skip);
2021 if (extra_refname)
2022 strbuf_addf(err, _("cannot process '%s' and '%s' at the same time"),
2023 refname, extra_refname);
2024 else
2025 ret = 0;
2026
2027 cleanup:
2028 strbuf_release(&referent);
2029 strbuf_release(&dirname);
2030 return ret;
2031 }
2032
2033 int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2034 {
2035 struct ref_iterator *iter;
2036
2037 iter = refs->be->reflog_iterator_begin(refs);
2038
2039 return do_for_each_ref_iterator(iter, fn, cb_data);
2040 }
2041
2042 int for_each_reflog(each_ref_fn fn, void *cb_data)
2043 {
2044 return refs_for_each_reflog(get_main_ref_store(the_repository), fn, cb_data);
2045 }
2046
2047 int refs_for_each_reflog_ent_reverse(struct ref_store *refs,
2048 const char *refname,
2049 each_reflog_ent_fn fn,
2050 void *cb_data)
2051 {
2052 return refs->be->for_each_reflog_ent_reverse(refs, refname,
2053 fn, cb_data);
2054 }
2055
2056 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
2057 void *cb_data)
2058 {
2059 return refs_for_each_reflog_ent_reverse(get_main_ref_store(the_repository),
2060 refname, fn, cb_data);
2061 }
2062
2063 int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname,
2064 each_reflog_ent_fn fn, void *cb_data)
2065 {
2066 return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
2067 }
2068
2069 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
2070 void *cb_data)
2071 {
2072 return refs_for_each_reflog_ent(get_main_ref_store(the_repository), refname,
2073 fn, cb_data);
2074 }
2075
2076 int refs_reflog_exists(struct ref_store *refs, const char *refname)
2077 {
2078 return refs->be->reflog_exists(refs, refname);
2079 }
2080
2081 int reflog_exists(const char *refname)
2082 {
2083 return refs_reflog_exists(get_main_ref_store(the_repository), refname);
2084 }
2085
2086 int refs_create_reflog(struct ref_store *refs, const char *refname,
2087 int force_create, struct strbuf *err)
2088 {
2089 return refs->be->create_reflog(refs, refname, force_create, err);
2090 }
2091
2092 int safe_create_reflog(const char *refname, int force_create,
2093 struct strbuf *err)
2094 {
2095 return refs_create_reflog(get_main_ref_store(the_repository), refname,
2096 force_create, err);
2097 }
2098
2099 int refs_delete_reflog(struct ref_store *refs, const char *refname)
2100 {
2101 return refs->be->delete_reflog(refs, refname);
2102 }
2103
2104 int delete_reflog(const char *refname)
2105 {
2106 return refs_delete_reflog(get_main_ref_store(the_repository), refname);
2107 }
2108
2109 int refs_reflog_expire(struct ref_store *refs,
2110 const char *refname, const struct object_id *oid,
2111 unsigned int flags,
2112 reflog_expiry_prepare_fn prepare_fn,
2113 reflog_expiry_should_prune_fn should_prune_fn,
2114 reflog_expiry_cleanup_fn cleanup_fn,
2115 void *policy_cb_data)
2116 {
2117 return refs->be->reflog_expire(refs, refname, oid, flags,
2118 prepare_fn, should_prune_fn,
2119 cleanup_fn, policy_cb_data);
2120 }
2121
2122 int reflog_expire(const char *refname, const struct object_id *oid,
2123 unsigned int flags,
2124 reflog_expiry_prepare_fn prepare_fn,
2125 reflog_expiry_should_prune_fn should_prune_fn,
2126 reflog_expiry_cleanup_fn cleanup_fn,
2127 void *policy_cb_data)
2128 {
2129 return refs_reflog_expire(get_main_ref_store(the_repository),
2130 refname, oid, flags,
2131 prepare_fn, should_prune_fn,
2132 cleanup_fn, policy_cb_data);
2133 }
2134
2135 int initial_ref_transaction_commit(struct ref_transaction *transaction,
2136 struct strbuf *err)
2137 {
2138 struct ref_store *refs = transaction->ref_store;
2139
2140 return refs->be->initial_transaction_commit(refs, transaction, err);
2141 }
2142
2143 int refs_delete_refs(struct ref_store *refs, const char *msg,
2144 struct string_list *refnames, unsigned int flags)
2145 {
2146 return refs->be->delete_refs(refs, msg, refnames, flags);
2147 }
2148
2149 int delete_refs(const char *msg, struct string_list *refnames,
2150 unsigned int flags)
2151 {
2152 return refs_delete_refs(get_main_ref_store(the_repository), msg, refnames, flags);
2153 }
2154
2155 int refs_rename_ref(struct ref_store *refs, const char *oldref,
2156 const char *newref, const char *logmsg)
2157 {
2158 return refs->be->rename_ref(refs, oldref, newref, logmsg);
2159 }
2160
2161 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
2162 {
2163 return refs_rename_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2164 }
2165
2166 int refs_copy_existing_ref(struct ref_store *refs, const char *oldref,
2167 const char *newref, const char *logmsg)
2168 {
2169 return refs->be->copy_ref(refs, oldref, newref, logmsg);
2170 }
2171
2172 int copy_existing_ref(const char *oldref, const char *newref, const char *logmsg)
2173 {
2174 return refs_copy_existing_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2175 }