Merge branch 'js/help-commands-verbose-by-default-fix' into maint
[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         const char *prefix;
221         each_ref_fn *fn;
222         void *cb_data;
223 };
224
225 int refs_read_ref_full(struct ref_store *refs, const char *refname,
226                        int resolve_flags, struct object_id *oid, int *flags)
227 {
228         if (refs_resolve_ref_unsafe(refs, refname, resolve_flags, oid, flags))
229                 return 0;
230         return -1;
231 }
232
233 int read_ref_full(const char *refname, int resolve_flags, struct object_id *oid, int *flags)
234 {
235         return refs_read_ref_full(get_main_ref_store(the_repository), refname,
236                                   resolve_flags, oid, flags);
237 }
238
239 int read_ref(const char *refname, struct object_id *oid)
240 {
241         return read_ref_full(refname, RESOLVE_REF_READING, oid, NULL);
242 }
243
244 int ref_exists(const char *refname)
245 {
246         return !!resolve_ref_unsafe(refname, RESOLVE_REF_READING, NULL, NULL);
247 }
248
249 static int match_ref_pattern(const char *refname,
250                              const struct string_list_item *item)
251 {
252         int matched = 0;
253         if (item->util == NULL) {
254                 if (!wildmatch(item->string, refname, 0))
255                         matched = 1;
256         } else {
257                 const char *rest;
258                 if (skip_prefix(refname, item->string, &rest) &&
259                     (!*rest || *rest == '/'))
260                         matched = 1;
261         }
262         return matched;
263 }
264
265 int ref_filter_match(const char *refname,
266                      const struct string_list *include_patterns,
267                      const struct string_list *exclude_patterns)
268 {
269         struct string_list_item *item;
270
271         if (exclude_patterns && exclude_patterns->nr) {
272                 for_each_string_list_item(item, exclude_patterns) {
273                         if (match_ref_pattern(refname, item))
274                                 return 0;
275                 }
276         }
277
278         if (include_patterns && include_patterns->nr) {
279                 int found = 0;
280                 for_each_string_list_item(item, include_patterns) {
281                         if (match_ref_pattern(refname, item)) {
282                                 found = 1;
283                                 break;
284                         }
285                 }
286
287                 if (!found)
288                         return 0;
289         }
290         return 1;
291 }
292
293 static int filter_refs(const char *refname, const struct object_id *oid,
294                            int flags, void *data)
295 {
296         struct ref_filter *filter = (struct ref_filter *)data;
297
298         if (wildmatch(filter->pattern, refname, 0))
299                 return 0;
300         if (filter->prefix)
301                 skip_prefix(refname, filter->prefix, &refname);
302         return filter->fn(refname, oid, flags, filter->cb_data);
303 }
304
305 enum peel_status peel_object(const struct object_id *name, struct object_id *oid)
306 {
307         struct object *o = lookup_unknown_object(name->hash);
308
309         if (o->type == OBJ_NONE) {
310                 int type = oid_object_info(the_repository, name, NULL);
311                 if (type < 0 || !object_as_type(the_repository, o, type, 0))
312                         return PEEL_INVALID;
313         }
314
315         if (o->type != OBJ_TAG)
316                 return PEEL_NON_TAG;
317
318         o = deref_tag_noverify(o);
319         if (!o)
320                 return PEEL_INVALID;
321
322         oidcpy(oid, &o->oid);
323         return PEEL_PEELED;
324 }
325
326 struct warn_if_dangling_data {
327         FILE *fp;
328         const char *refname;
329         const struct string_list *refnames;
330         const char *msg_fmt;
331 };
332
333 static int warn_if_dangling_symref(const char *refname, const struct object_id *oid,
334                                    int flags, void *cb_data)
335 {
336         struct warn_if_dangling_data *d = cb_data;
337         const char *resolves_to;
338
339         if (!(flags & REF_ISSYMREF))
340                 return 0;
341
342         resolves_to = resolve_ref_unsafe(refname, 0, NULL, NULL);
343         if (!resolves_to
344             || (d->refname
345                 ? strcmp(resolves_to, d->refname)
346                 : !string_list_has_string(d->refnames, resolves_to))) {
347                 return 0;
348         }
349
350         fprintf(d->fp, d->msg_fmt, refname);
351         fputc('\n', d->fp);
352         return 0;
353 }
354
355 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
356 {
357         struct warn_if_dangling_data data;
358
359         data.fp = fp;
360         data.refname = refname;
361         data.refnames = NULL;
362         data.msg_fmt = msg_fmt;
363         for_each_rawref(warn_if_dangling_symref, &data);
364 }
365
366 void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames)
367 {
368         struct warn_if_dangling_data data;
369
370         data.fp = fp;
371         data.refname = NULL;
372         data.refnames = refnames;
373         data.msg_fmt = msg_fmt;
374         for_each_rawref(warn_if_dangling_symref, &data);
375 }
376
377 int refs_for_each_tag_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
378 {
379         return refs_for_each_ref_in(refs, "refs/tags/", fn, cb_data);
380 }
381
382 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
383 {
384         return refs_for_each_tag_ref(get_main_ref_store(the_repository), fn, cb_data);
385 }
386
387 int refs_for_each_branch_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
388 {
389         return refs_for_each_ref_in(refs, "refs/heads/", fn, cb_data);
390 }
391
392 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
393 {
394         return refs_for_each_branch_ref(get_main_ref_store(the_repository), fn, cb_data);
395 }
396
397 int refs_for_each_remote_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
398 {
399         return refs_for_each_ref_in(refs, "refs/remotes/", fn, cb_data);
400 }
401
402 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
403 {
404         return refs_for_each_remote_ref(get_main_ref_store(the_repository), fn, cb_data);
405 }
406
407 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
408 {
409         struct strbuf buf = STRBUF_INIT;
410         int ret = 0;
411         struct object_id oid;
412         int flag;
413
414         strbuf_addf(&buf, "%sHEAD", get_git_namespace());
415         if (!read_ref_full(buf.buf, RESOLVE_REF_READING, &oid, &flag))
416                 ret = fn(buf.buf, &oid, flag, cb_data);
417         strbuf_release(&buf);
418
419         return ret;
420 }
421
422 void normalize_glob_ref(struct string_list_item *item, const char *prefix,
423                         const char *pattern)
424 {
425         struct strbuf normalized_pattern = STRBUF_INIT;
426
427         if (*pattern == '/')
428                 BUG("pattern must not start with '/'");
429
430         if (prefix) {
431                 strbuf_addstr(&normalized_pattern, prefix);
432         }
433         else if (!starts_with(pattern, "refs/"))
434                 strbuf_addstr(&normalized_pattern, "refs/");
435         strbuf_addstr(&normalized_pattern, pattern);
436         strbuf_strip_suffix(&normalized_pattern, "/");
437
438         item->string = strbuf_detach(&normalized_pattern, NULL);
439         item->util = has_glob_specials(pattern) ? NULL : item->string;
440         strbuf_release(&normalized_pattern);
441 }
442
443 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
444         const char *prefix, void *cb_data)
445 {
446         struct strbuf real_pattern = STRBUF_INIT;
447         struct ref_filter filter;
448         int ret;
449
450         if (!prefix && !starts_with(pattern, "refs/"))
451                 strbuf_addstr(&real_pattern, "refs/");
452         else if (prefix)
453                 strbuf_addstr(&real_pattern, prefix);
454         strbuf_addstr(&real_pattern, pattern);
455
456         if (!has_glob_specials(pattern)) {
457                 /* Append implied '/' '*' if not present. */
458                 strbuf_complete(&real_pattern, '/');
459                 /* No need to check for '*', there is none. */
460                 strbuf_addch(&real_pattern, '*');
461         }
462
463         filter.pattern = real_pattern.buf;
464         filter.prefix = prefix;
465         filter.fn = fn;
466         filter.cb_data = cb_data;
467         ret = for_each_ref(filter_refs, &filter);
468
469         strbuf_release(&real_pattern);
470         return ret;
471 }
472
473 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
474 {
475         return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
476 }
477
478 const char *prettify_refname(const char *name)
479 {
480         if (skip_prefix(name, "refs/heads/", &name) ||
481             skip_prefix(name, "refs/tags/", &name) ||
482             skip_prefix(name, "refs/remotes/", &name))
483                 ; /* nothing */
484         return name;
485 }
486
487 static const char *ref_rev_parse_rules[] = {
488         "%.*s",
489         "refs/%.*s",
490         "refs/tags/%.*s",
491         "refs/heads/%.*s",
492         "refs/remotes/%.*s",
493         "refs/remotes/%.*s/HEAD",
494         NULL
495 };
496
497 #define NUM_REV_PARSE_RULES (ARRAY_SIZE(ref_rev_parse_rules) - 1)
498
499 /*
500  * Is it possible that the caller meant full_name with abbrev_name?
501  * If so return a non-zero value to signal "yes"; the magnitude of
502  * the returned value gives the precedence used for disambiguation.
503  *
504  * If abbrev_name cannot mean full_name, return 0.
505  */
506 int refname_match(const char *abbrev_name, const char *full_name)
507 {
508         const char **p;
509         const int abbrev_name_len = strlen(abbrev_name);
510         const int num_rules = NUM_REV_PARSE_RULES;
511
512         for (p = ref_rev_parse_rules; *p; p++)
513                 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name)))
514                         return &ref_rev_parse_rules[num_rules] - p;
515
516         return 0;
517 }
518
519 /*
520  * Given a 'prefix' expand it by the rules in 'ref_rev_parse_rules' and add
521  * the results to 'prefixes'
522  */
523 void expand_ref_prefix(struct argv_array *prefixes, const char *prefix)
524 {
525         const char **p;
526         int len = strlen(prefix);
527
528         for (p = ref_rev_parse_rules; *p; p++)
529                 argv_array_pushf(prefixes, *p, len, prefix);
530 }
531
532 /*
533  * *string and *len will only be substituted, and *string returned (for
534  * later free()ing) if the string passed in is a magic short-hand form
535  * to name a branch.
536  */
537 static char *substitute_branch_name(const char **string, int *len)
538 {
539         struct strbuf buf = STRBUF_INIT;
540         int ret = interpret_branch_name(*string, *len, &buf, 0);
541
542         if (ret == *len) {
543                 size_t size;
544                 *string = strbuf_detach(&buf, &size);
545                 *len = size;
546                 return (char *)*string;
547         }
548
549         return NULL;
550 }
551
552 int dwim_ref(const char *str, int len, struct object_id *oid, char **ref)
553 {
554         char *last_branch = substitute_branch_name(&str, &len);
555         int   refs_found  = expand_ref(str, len, oid, ref);
556         free(last_branch);
557         return refs_found;
558 }
559
560 int expand_ref(const char *str, int len, struct object_id *oid, char **ref)
561 {
562         const char **p, *r;
563         int refs_found = 0;
564         struct strbuf fullref = STRBUF_INIT;
565
566         *ref = NULL;
567         for (p = ref_rev_parse_rules; *p; p++) {
568                 struct object_id oid_from_ref;
569                 struct object_id *this_result;
570                 int flag;
571
572                 this_result = refs_found ? &oid_from_ref : oid;
573                 strbuf_reset(&fullref);
574                 strbuf_addf(&fullref, *p, len, str);
575                 r = resolve_ref_unsafe(fullref.buf, RESOLVE_REF_READING,
576                                        this_result, &flag);
577                 if (r) {
578                         if (!refs_found++)
579                                 *ref = xstrdup(r);
580                         if (!warn_ambiguous_refs)
581                                 break;
582                 } else if ((flag & REF_ISSYMREF) && strcmp(fullref.buf, "HEAD")) {
583                         warning(_("ignoring dangling symref %s"), fullref.buf);
584                 } else if ((flag & REF_ISBROKEN) && strchr(fullref.buf, '/')) {
585                         warning(_("ignoring broken ref %s"), fullref.buf);
586                 }
587         }
588         strbuf_release(&fullref);
589         return refs_found;
590 }
591
592 int dwim_log(const char *str, int len, struct object_id *oid, char **log)
593 {
594         char *last_branch = substitute_branch_name(&str, &len);
595         const char **p;
596         int logs_found = 0;
597         struct strbuf path = STRBUF_INIT;
598
599         *log = NULL;
600         for (p = ref_rev_parse_rules; *p; p++) {
601                 struct object_id hash;
602                 const char *ref, *it;
603
604                 strbuf_reset(&path);
605                 strbuf_addf(&path, *p, len, str);
606                 ref = resolve_ref_unsafe(path.buf, RESOLVE_REF_READING,
607                                          &hash, NULL);
608                 if (!ref)
609                         continue;
610                 if (reflog_exists(path.buf))
611                         it = path.buf;
612                 else if (strcmp(ref, path.buf) && reflog_exists(ref))
613                         it = ref;
614                 else
615                         continue;
616                 if (!logs_found++) {
617                         *log = xstrdup(it);
618                         oidcpy(oid, &hash);
619                 }
620                 if (!warn_ambiguous_refs)
621                         break;
622         }
623         strbuf_release(&path);
624         free(last_branch);
625         return logs_found;
626 }
627
628 static int is_per_worktree_ref(const char *refname)
629 {
630         return !strcmp(refname, "HEAD") ||
631                 starts_with(refname, "refs/worktree/") ||
632                 starts_with(refname, "refs/bisect/") ||
633                 starts_with(refname, "refs/rewritten/");
634 }
635
636 static int is_pseudoref_syntax(const char *refname)
637 {
638         const char *c;
639
640         for (c = refname; *c; c++) {
641                 if (!isupper(*c) && *c != '-' && *c != '_')
642                         return 0;
643         }
644
645         return 1;
646 }
647
648 static int is_main_pseudoref_syntax(const char *refname)
649 {
650         return skip_prefix(refname, "main-worktree/", &refname) &&
651                 *refname &&
652                 is_pseudoref_syntax(refname);
653 }
654
655 static int is_other_pseudoref_syntax(const char *refname)
656 {
657         if (!skip_prefix(refname, "worktrees/", &refname))
658                 return 0;
659         refname = strchr(refname, '/');
660         if (!refname || !refname[1])
661                 return 0;
662         return is_pseudoref_syntax(refname + 1);
663 }
664
665 enum ref_type ref_type(const char *refname)
666 {
667         if (is_per_worktree_ref(refname))
668                 return REF_TYPE_PER_WORKTREE;
669         if (is_pseudoref_syntax(refname))
670                 return REF_TYPE_PSEUDOREF;
671         if (is_main_pseudoref_syntax(refname))
672                 return REF_TYPE_MAIN_PSEUDOREF;
673         if (is_other_pseudoref_syntax(refname))
674                 return REF_TYPE_OTHER_PSEUDOREF;
675         return REF_TYPE_NORMAL;
676 }
677
678 long get_files_ref_lock_timeout_ms(void)
679 {
680         static int configured = 0;
681
682         /* The default timeout is 100 ms: */
683         static int timeout_ms = 100;
684
685         if (!configured) {
686                 git_config_get_int("core.filesreflocktimeout", &timeout_ms);
687                 configured = 1;
688         }
689
690         return timeout_ms;
691 }
692
693 static int write_pseudoref(const char *pseudoref, const struct object_id *oid,
694                            const struct object_id *old_oid, struct strbuf *err)
695 {
696         const char *filename;
697         int fd;
698         struct lock_file lock = LOCK_INIT;
699         struct strbuf buf = STRBUF_INIT;
700         int ret = -1;
701
702         if (!oid)
703                 return 0;
704
705         strbuf_addf(&buf, "%s\n", oid_to_hex(oid));
706
707         filename = git_path("%s", pseudoref);
708         fd = hold_lock_file_for_update_timeout(&lock, filename, 0,
709                                                get_files_ref_lock_timeout_ms());
710         if (fd < 0) {
711                 strbuf_addf(err, _("could not open '%s' for writing: %s"),
712                             filename, strerror(errno));
713                 goto done;
714         }
715
716         if (old_oid) {
717                 struct object_id actual_old_oid;
718
719                 if (read_ref(pseudoref, &actual_old_oid)) {
720                         if (!is_null_oid(old_oid)) {
721                                 strbuf_addf(err, _("could not read ref '%s'"),
722                                             pseudoref);
723                                 rollback_lock_file(&lock);
724                                 goto done;
725                         }
726                 } else if (is_null_oid(old_oid)) {
727                         strbuf_addf(err, _("ref '%s' already exists"),
728                                     pseudoref);
729                         rollback_lock_file(&lock);
730                         goto done;
731                 } else if (!oideq(&actual_old_oid, old_oid)) {
732                         strbuf_addf(err, _("unexpected object ID when writing '%s'"),
733                                     pseudoref);
734                         rollback_lock_file(&lock);
735                         goto done;
736                 }
737         }
738
739         if (write_in_full(fd, buf.buf, buf.len) < 0) {
740                 strbuf_addf(err, _("could not write to '%s'"), filename);
741                 rollback_lock_file(&lock);
742                 goto done;
743         }
744
745         commit_lock_file(&lock);
746         ret = 0;
747 done:
748         strbuf_release(&buf);
749         return ret;
750 }
751
752 static int delete_pseudoref(const char *pseudoref, const struct object_id *old_oid)
753 {
754         const char *filename;
755
756         filename = git_path("%s", pseudoref);
757
758         if (old_oid && !is_null_oid(old_oid)) {
759                 struct lock_file lock = LOCK_INIT;
760                 int fd;
761                 struct object_id actual_old_oid;
762
763                 fd = hold_lock_file_for_update_timeout(
764                                 &lock, filename, 0,
765                                 get_files_ref_lock_timeout_ms());
766                 if (fd < 0) {
767                         error_errno(_("could not open '%s' for writing"),
768                                     filename);
769                         return -1;
770                 }
771                 if (read_ref(pseudoref, &actual_old_oid))
772                         die(_("could not read ref '%s'"), pseudoref);
773                 if (!oideq(&actual_old_oid, old_oid)) {
774                         error(_("unexpected object ID when deleting '%s'"),
775                               pseudoref);
776                         rollback_lock_file(&lock);
777                         return -1;
778                 }
779
780                 unlink(filename);
781                 rollback_lock_file(&lock);
782         } else {
783                 unlink(filename);
784         }
785
786         return 0;
787 }
788
789 int refs_delete_ref(struct ref_store *refs, const char *msg,
790                     const char *refname,
791                     const struct object_id *old_oid,
792                     unsigned int flags)
793 {
794         struct ref_transaction *transaction;
795         struct strbuf err = STRBUF_INIT;
796
797         if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
798                 assert(refs == get_main_ref_store(the_repository));
799                 return delete_pseudoref(refname, old_oid);
800         }
801
802         transaction = ref_store_transaction_begin(refs, &err);
803         if (!transaction ||
804             ref_transaction_delete(transaction, refname, old_oid,
805                                    flags, msg, &err) ||
806             ref_transaction_commit(transaction, &err)) {
807                 error("%s", err.buf);
808                 ref_transaction_free(transaction);
809                 strbuf_release(&err);
810                 return 1;
811         }
812         ref_transaction_free(transaction);
813         strbuf_release(&err);
814         return 0;
815 }
816
817 int delete_ref(const char *msg, const char *refname,
818                const struct object_id *old_oid, unsigned int flags)
819 {
820         return refs_delete_ref(get_main_ref_store(the_repository), msg, refname,
821                                old_oid, flags);
822 }
823
824 void copy_reflog_msg(struct strbuf *sb, const char *msg)
825 {
826         char c;
827         int wasspace = 1;
828
829         strbuf_addch(sb, '\t');
830         while ((c = *msg++)) {
831                 if (wasspace && isspace(c))
832                         continue;
833                 wasspace = isspace(c);
834                 if (wasspace)
835                         c = ' ';
836                 strbuf_addch(sb, c);
837         }
838         strbuf_rtrim(sb);
839 }
840
841 int should_autocreate_reflog(const char *refname)
842 {
843         switch (log_all_ref_updates) {
844         case LOG_REFS_ALWAYS:
845                 return 1;
846         case LOG_REFS_NORMAL:
847                 return starts_with(refname, "refs/heads/") ||
848                         starts_with(refname, "refs/remotes/") ||
849                         starts_with(refname, "refs/notes/") ||
850                         !strcmp(refname, "HEAD");
851         default:
852                 return 0;
853         }
854 }
855
856 int is_branch(const char *refname)
857 {
858         return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
859 }
860
861 struct read_ref_at_cb {
862         const char *refname;
863         timestamp_t at_time;
864         int cnt;
865         int reccnt;
866         struct object_id *oid;
867         int found_it;
868
869         struct object_id ooid;
870         struct object_id noid;
871         int tz;
872         timestamp_t date;
873         char **msg;
874         timestamp_t *cutoff_time;
875         int *cutoff_tz;
876         int *cutoff_cnt;
877 };
878
879 static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
880                 const char *email, timestamp_t timestamp, int tz,
881                 const char *message, void *cb_data)
882 {
883         struct read_ref_at_cb *cb = cb_data;
884
885         cb->reccnt++;
886         cb->tz = tz;
887         cb->date = timestamp;
888
889         if (timestamp <= cb->at_time || cb->cnt == 0) {
890                 if (cb->msg)
891                         *cb->msg = xstrdup(message);
892                 if (cb->cutoff_time)
893                         *cb->cutoff_time = timestamp;
894                 if (cb->cutoff_tz)
895                         *cb->cutoff_tz = tz;
896                 if (cb->cutoff_cnt)
897                         *cb->cutoff_cnt = cb->reccnt - 1;
898                 /*
899                  * we have not yet updated cb->[n|o]oid so they still
900                  * hold the values for the previous record.
901                  */
902                 if (!is_null_oid(&cb->ooid)) {
903                         oidcpy(cb->oid, noid);
904                         if (!oideq(&cb->ooid, noid))
905                                 warning(_("log for ref %s has gap after %s"),
906                                         cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
907                 }
908                 else if (cb->date == cb->at_time)
909                         oidcpy(cb->oid, noid);
910                 else if (!oideq(noid, cb->oid))
911                         warning(_("log for ref %s unexpectedly ended on %s"),
912                                 cb->refname, show_date(cb->date, cb->tz,
913                                                        DATE_MODE(RFC2822)));
914                 oidcpy(&cb->ooid, ooid);
915                 oidcpy(&cb->noid, noid);
916                 cb->found_it = 1;
917                 return 1;
918         }
919         oidcpy(&cb->ooid, ooid);
920         oidcpy(&cb->noid, noid);
921         if (cb->cnt > 0)
922                 cb->cnt--;
923         return 0;
924 }
925
926 static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
927                                   const char *email, timestamp_t timestamp,
928                                   int tz, const char *message, void *cb_data)
929 {
930         struct read_ref_at_cb *cb = cb_data;
931
932         if (cb->msg)
933                 *cb->msg = xstrdup(message);
934         if (cb->cutoff_time)
935                 *cb->cutoff_time = timestamp;
936         if (cb->cutoff_tz)
937                 *cb->cutoff_tz = tz;
938         if (cb->cutoff_cnt)
939                 *cb->cutoff_cnt = cb->reccnt;
940         oidcpy(cb->oid, ooid);
941         if (is_null_oid(cb->oid))
942                 oidcpy(cb->oid, noid);
943         /* We just want the first entry */
944         return 1;
945 }
946
947 int read_ref_at(const char *refname, unsigned int flags, timestamp_t at_time, int cnt,
948                 struct object_id *oid, char **msg,
949                 timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
950 {
951         struct read_ref_at_cb cb;
952
953         memset(&cb, 0, sizeof(cb));
954         cb.refname = refname;
955         cb.at_time = at_time;
956         cb.cnt = cnt;
957         cb.msg = msg;
958         cb.cutoff_time = cutoff_time;
959         cb.cutoff_tz = cutoff_tz;
960         cb.cutoff_cnt = cutoff_cnt;
961         cb.oid = oid;
962
963         for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
964
965         if (!cb.reccnt) {
966                 if (flags & GET_OID_QUIETLY)
967                         exit(128);
968                 else
969                         die(_("log for %s is empty"), refname);
970         }
971         if (cb.found_it)
972                 return 0;
973
974         for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
975
976         return 1;
977 }
978
979 struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs,
980                                                     struct strbuf *err)
981 {
982         struct ref_transaction *tr;
983         assert(err);
984
985         tr = xcalloc(1, sizeof(struct ref_transaction));
986         tr->ref_store = refs;
987         return tr;
988 }
989
990 struct ref_transaction *ref_transaction_begin(struct strbuf *err)
991 {
992         return ref_store_transaction_begin(get_main_ref_store(the_repository), err);
993 }
994
995 void ref_transaction_free(struct ref_transaction *transaction)
996 {
997         size_t i;
998
999         if (!transaction)
1000                 return;
1001
1002         switch (transaction->state) {
1003         case REF_TRANSACTION_OPEN:
1004         case REF_TRANSACTION_CLOSED:
1005                 /* OK */
1006                 break;
1007         case REF_TRANSACTION_PREPARED:
1008                 BUG("free called on a prepared reference transaction");
1009                 break;
1010         default:
1011                 BUG("unexpected reference transaction state");
1012                 break;
1013         }
1014
1015         for (i = 0; i < transaction->nr; i++) {
1016                 free(transaction->updates[i]->msg);
1017                 free(transaction->updates[i]);
1018         }
1019         free(transaction->updates);
1020         free(transaction);
1021 }
1022
1023 struct ref_update *ref_transaction_add_update(
1024                 struct ref_transaction *transaction,
1025                 const char *refname, unsigned int flags,
1026                 const struct object_id *new_oid,
1027                 const struct object_id *old_oid,
1028                 const char *msg)
1029 {
1030         struct ref_update *update;
1031
1032         if (transaction->state != REF_TRANSACTION_OPEN)
1033                 BUG("update called for transaction that is not open");
1034
1035         FLEX_ALLOC_STR(update, refname, refname);
1036         ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
1037         transaction->updates[transaction->nr++] = update;
1038
1039         update->flags = flags;
1040
1041         if (flags & REF_HAVE_NEW)
1042                 oidcpy(&update->new_oid, new_oid);
1043         if (flags & REF_HAVE_OLD)
1044                 oidcpy(&update->old_oid, old_oid);
1045         update->msg = xstrdup_or_null(msg);
1046         return update;
1047 }
1048
1049 int ref_transaction_update(struct ref_transaction *transaction,
1050                            const char *refname,
1051                            const struct object_id *new_oid,
1052                            const struct object_id *old_oid,
1053                            unsigned int flags, const char *msg,
1054                            struct strbuf *err)
1055 {
1056         assert(err);
1057
1058         if ((new_oid && !is_null_oid(new_oid)) ?
1059             check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
1060             !refname_is_safe(refname)) {
1061                 strbuf_addf(err, _("refusing to update ref with bad name '%s'"),
1062                             refname);
1063                 return -1;
1064         }
1065
1066         if (flags & ~REF_TRANSACTION_UPDATE_ALLOWED_FLAGS)
1067                 BUG("illegal flags 0x%x passed to ref_transaction_update()", flags);
1068
1069         flags |= (new_oid ? REF_HAVE_NEW : 0) | (old_oid ? REF_HAVE_OLD : 0);
1070
1071         ref_transaction_add_update(transaction, refname, flags,
1072                                    new_oid, old_oid, msg);
1073         return 0;
1074 }
1075
1076 int ref_transaction_create(struct ref_transaction *transaction,
1077                            const char *refname,
1078                            const struct object_id *new_oid,
1079                            unsigned int flags, const char *msg,
1080                            struct strbuf *err)
1081 {
1082         if (!new_oid || is_null_oid(new_oid))
1083                 BUG("create called without valid new_oid");
1084         return ref_transaction_update(transaction, refname, new_oid,
1085                                       &null_oid, flags, msg, err);
1086 }
1087
1088 int ref_transaction_delete(struct ref_transaction *transaction,
1089                            const char *refname,
1090                            const struct object_id *old_oid,
1091                            unsigned int flags, const char *msg,
1092                            struct strbuf *err)
1093 {
1094         if (old_oid && is_null_oid(old_oid))
1095                 BUG("delete called with old_oid set to zeros");
1096         return ref_transaction_update(transaction, refname,
1097                                       &null_oid, old_oid,
1098                                       flags, msg, err);
1099 }
1100
1101 int ref_transaction_verify(struct ref_transaction *transaction,
1102                            const char *refname,
1103                            const struct object_id *old_oid,
1104                            unsigned int flags,
1105                            struct strbuf *err)
1106 {
1107         if (!old_oid)
1108                 BUG("verify called with old_oid set to NULL");
1109         return ref_transaction_update(transaction, refname,
1110                                       NULL, old_oid,
1111                                       flags, NULL, err);
1112 }
1113
1114 int refs_update_ref(struct ref_store *refs, const char *msg,
1115                     const char *refname, const struct object_id *new_oid,
1116                     const struct object_id *old_oid, unsigned int flags,
1117                     enum action_on_err onerr)
1118 {
1119         struct ref_transaction *t = NULL;
1120         struct strbuf err = STRBUF_INIT;
1121         int ret = 0;
1122
1123         if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
1124                 assert(refs == get_main_ref_store(the_repository));
1125                 ret = write_pseudoref(refname, new_oid, old_oid, &err);
1126         } else {
1127                 t = ref_store_transaction_begin(refs, &err);
1128                 if (!t ||
1129                     ref_transaction_update(t, refname, new_oid, old_oid,
1130                                            flags, msg, &err) ||
1131                     ref_transaction_commit(t, &err)) {
1132                         ret = 1;
1133                         ref_transaction_free(t);
1134                 }
1135         }
1136         if (ret) {
1137                 const char *str = _("update_ref failed for ref '%s': %s");
1138
1139                 switch (onerr) {
1140                 case UPDATE_REFS_MSG_ON_ERR:
1141                         error(str, refname, err.buf);
1142                         break;
1143                 case UPDATE_REFS_DIE_ON_ERR:
1144                         die(str, refname, err.buf);
1145                         break;
1146                 case UPDATE_REFS_QUIET_ON_ERR:
1147                         break;
1148                 }
1149                 strbuf_release(&err);
1150                 return 1;
1151         }
1152         strbuf_release(&err);
1153         if (t)
1154                 ref_transaction_free(t);
1155         return 0;
1156 }
1157
1158 int update_ref(const char *msg, const char *refname,
1159                const struct object_id *new_oid,
1160                const struct object_id *old_oid,
1161                unsigned int flags, enum action_on_err onerr)
1162 {
1163         return refs_update_ref(get_main_ref_store(the_repository), msg, refname, new_oid,
1164                                old_oid, flags, onerr);
1165 }
1166
1167 char *shorten_unambiguous_ref(const char *refname, int strict)
1168 {
1169         int i;
1170         static char **scanf_fmts;
1171         static int nr_rules;
1172         char *short_name;
1173         struct strbuf resolved_buf = STRBUF_INIT;
1174
1175         if (!nr_rules) {
1176                 /*
1177                  * Pre-generate scanf formats from ref_rev_parse_rules[].
1178                  * Generate a format suitable for scanf from a
1179                  * ref_rev_parse_rules rule by interpolating "%s" at the
1180                  * location of the "%.*s".
1181                  */
1182                 size_t total_len = 0;
1183                 size_t offset = 0;
1184
1185                 /* the rule list is NULL terminated, count them first */
1186                 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
1187                         /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
1188                         total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
1189
1190                 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
1191
1192                 offset = 0;
1193                 for (i = 0; i < nr_rules; i++) {
1194                         assert(offset < total_len);
1195                         scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
1196                         offset += xsnprintf(scanf_fmts[i], total_len - offset,
1197                                             ref_rev_parse_rules[i], 2, "%s") + 1;
1198                 }
1199         }
1200
1201         /* bail out if there are no rules */
1202         if (!nr_rules)
1203                 return xstrdup(refname);
1204
1205         /* buffer for scanf result, at most refname must fit */
1206         short_name = xstrdup(refname);
1207
1208         /* skip first rule, it will always match */
1209         for (i = nr_rules - 1; i > 0 ; --i) {
1210                 int j;
1211                 int rules_to_fail = i;
1212                 int short_name_len;
1213
1214                 if (1 != sscanf(refname, scanf_fmts[i], short_name))
1215                         continue;
1216
1217                 short_name_len = strlen(short_name);
1218
1219                 /*
1220                  * in strict mode, all (except the matched one) rules
1221                  * must fail to resolve to a valid non-ambiguous ref
1222                  */
1223                 if (strict)
1224                         rules_to_fail = nr_rules;
1225
1226                 /*
1227                  * check if the short name resolves to a valid ref,
1228                  * but use only rules prior to the matched one
1229                  */
1230                 for (j = 0; j < rules_to_fail; j++) {
1231                         const char *rule = ref_rev_parse_rules[j];
1232
1233                         /* skip matched rule */
1234                         if (i == j)
1235                                 continue;
1236
1237                         /*
1238                          * the short name is ambiguous, if it resolves
1239                          * (with this previous rule) to a valid ref
1240                          * read_ref() returns 0 on success
1241                          */
1242                         strbuf_reset(&resolved_buf);
1243                         strbuf_addf(&resolved_buf, rule,
1244                                     short_name_len, short_name);
1245                         if (ref_exists(resolved_buf.buf))
1246                                 break;
1247                 }
1248
1249                 /*
1250                  * short name is non-ambiguous if all previous rules
1251                  * haven't resolved to a valid ref
1252                  */
1253                 if (j == rules_to_fail) {
1254                         strbuf_release(&resolved_buf);
1255                         return short_name;
1256                 }
1257         }
1258
1259         strbuf_release(&resolved_buf);
1260         free(short_name);
1261         return xstrdup(refname);
1262 }
1263
1264 static struct string_list *hide_refs;
1265
1266 int parse_hide_refs_config(const char *var, const char *value, const char *section)
1267 {
1268         const char *key;
1269         if (!strcmp("transfer.hiderefs", var) ||
1270             (!parse_config_key(var, section, NULL, NULL, &key) &&
1271              !strcmp(key, "hiderefs"))) {
1272                 char *ref;
1273                 int len;
1274
1275                 if (!value)
1276                         return config_error_nonbool(var);
1277                 ref = xstrdup(value);
1278                 len = strlen(ref);
1279                 while (len && ref[len - 1] == '/')
1280                         ref[--len] = '\0';
1281                 if (!hide_refs) {
1282                         hide_refs = xcalloc(1, sizeof(*hide_refs));
1283                         hide_refs->strdup_strings = 1;
1284                 }
1285                 string_list_append(hide_refs, ref);
1286         }
1287         return 0;
1288 }
1289
1290 int ref_is_hidden(const char *refname, const char *refname_full)
1291 {
1292         int i;
1293
1294         if (!hide_refs)
1295                 return 0;
1296         for (i = hide_refs->nr - 1; i >= 0; i--) {
1297                 const char *match = hide_refs->items[i].string;
1298                 const char *subject;
1299                 int neg = 0;
1300                 const char *p;
1301
1302                 if (*match == '!') {
1303                         neg = 1;
1304                         match++;
1305                 }
1306
1307                 if (*match == '^') {
1308                         subject = refname_full;
1309                         match++;
1310                 } else {
1311                         subject = refname;
1312                 }
1313
1314                 /* refname can be NULL when namespaces are used. */
1315                 if (subject &&
1316                     skip_prefix(subject, match, &p) &&
1317                     (!*p || *p == '/'))
1318                         return !neg;
1319         }
1320         return 0;
1321 }
1322
1323 const char *find_descendant_ref(const char *dirname,
1324                                 const struct string_list *extras,
1325                                 const struct string_list *skip)
1326 {
1327         int pos;
1328
1329         if (!extras)
1330                 return NULL;
1331
1332         /*
1333          * Look at the place where dirname would be inserted into
1334          * extras. If there is an entry at that position that starts
1335          * with dirname (remember, dirname includes the trailing
1336          * slash) and is not in skip, then we have a conflict.
1337          */
1338         for (pos = string_list_find_insert_index(extras, dirname, 0);
1339              pos < extras->nr; pos++) {
1340                 const char *extra_refname = extras->items[pos].string;
1341
1342                 if (!starts_with(extra_refname, dirname))
1343                         break;
1344
1345                 if (!skip || !string_list_has_string(skip, extra_refname))
1346                         return extra_refname;
1347         }
1348         return NULL;
1349 }
1350
1351 int refs_rename_ref_available(struct ref_store *refs,
1352                               const char *old_refname,
1353                               const char *new_refname)
1354 {
1355         struct string_list skip = STRING_LIST_INIT_NODUP;
1356         struct strbuf err = STRBUF_INIT;
1357         int ok;
1358
1359         string_list_insert(&skip, old_refname);
1360         ok = !refs_verify_refname_available(refs, new_refname,
1361                                             NULL, &skip, &err);
1362         if (!ok)
1363                 error("%s", err.buf);
1364
1365         string_list_clear(&skip, 0);
1366         strbuf_release(&err);
1367         return ok;
1368 }
1369
1370 int refs_head_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1371 {
1372         struct object_id oid;
1373         int flag;
1374
1375         if (!refs_read_ref_full(refs, "HEAD", RESOLVE_REF_READING,
1376                                 &oid, &flag))
1377                 return fn("HEAD", &oid, flag, cb_data);
1378
1379         return 0;
1380 }
1381
1382 int head_ref(each_ref_fn fn, void *cb_data)
1383 {
1384         return refs_head_ref(get_main_ref_store(the_repository), fn, cb_data);
1385 }
1386
1387 struct ref_iterator *refs_ref_iterator_begin(
1388                 struct ref_store *refs,
1389                 const char *prefix, int trim, int flags)
1390 {
1391         struct ref_iterator *iter;
1392
1393         if (ref_paranoia < 0)
1394                 ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
1395         if (ref_paranoia)
1396                 flags |= DO_FOR_EACH_INCLUDE_BROKEN;
1397
1398         iter = refs->be->iterator_begin(refs, prefix, flags);
1399
1400         /*
1401          * `iterator_begin()` already takes care of prefix, but we
1402          * might need to do some trimming:
1403          */
1404         if (trim)
1405                 iter = prefix_ref_iterator_begin(iter, "", trim);
1406
1407         /* Sanity check for subclasses: */
1408         if (!iter->ordered)
1409                 BUG("reference iterator is not ordered");
1410
1411         return iter;
1412 }
1413
1414 /*
1415  * Call fn for each reference in the specified submodule for which the
1416  * refname begins with prefix. If trim is non-zero, then trim that
1417  * many characters off the beginning of each refname before passing
1418  * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1419  * include broken references in the iteration. If fn ever returns a
1420  * non-zero value, stop the iteration and return that value;
1421  * otherwise, return 0.
1422  */
1423 static int do_for_each_repo_ref(struct repository *r, const char *prefix,
1424                                 each_repo_ref_fn fn, int trim, int flags,
1425                                 void *cb_data)
1426 {
1427         struct ref_iterator *iter;
1428         struct ref_store *refs = get_main_ref_store(r);
1429
1430         if (!refs)
1431                 return 0;
1432
1433         iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1434
1435         return do_for_each_repo_ref_iterator(r, iter, fn, cb_data);
1436 }
1437
1438 struct do_for_each_ref_help {
1439         each_ref_fn *fn;
1440         void *cb_data;
1441 };
1442
1443 static int do_for_each_ref_helper(struct repository *r,
1444                                   const char *refname,
1445                                   const struct object_id *oid,
1446                                   int flags,
1447                                   void *cb_data)
1448 {
1449         struct do_for_each_ref_help *hp = cb_data;
1450
1451         return hp->fn(refname, oid, flags, hp->cb_data);
1452 }
1453
1454 static int do_for_each_ref(struct ref_store *refs, const char *prefix,
1455                            each_ref_fn fn, int trim, int flags, void *cb_data)
1456 {
1457         struct ref_iterator *iter;
1458         struct do_for_each_ref_help hp = { fn, cb_data };
1459
1460         if (!refs)
1461                 return 0;
1462
1463         iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1464
1465         return do_for_each_repo_ref_iterator(the_repository, iter,
1466                                         do_for_each_ref_helper, &hp);
1467 }
1468
1469 int refs_for_each_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1470 {
1471         return do_for_each_ref(refs, "", fn, 0, 0, cb_data);
1472 }
1473
1474 int for_each_ref(each_ref_fn fn, void *cb_data)
1475 {
1476         return refs_for_each_ref(get_main_ref_store(the_repository), fn, cb_data);
1477 }
1478
1479 int refs_for_each_ref_in(struct ref_store *refs, const char *prefix,
1480                          each_ref_fn fn, void *cb_data)
1481 {
1482         return do_for_each_ref(refs, prefix, fn, strlen(prefix), 0, cb_data);
1483 }
1484
1485 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1486 {
1487         return refs_for_each_ref_in(get_main_ref_store(the_repository), prefix, fn, cb_data);
1488 }
1489
1490 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1491 {
1492         unsigned int flag = 0;
1493
1494         if (broken)
1495                 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1496         return do_for_each_ref(get_main_ref_store(the_repository),
1497                                prefix, fn, 0, flag, cb_data);
1498 }
1499
1500 int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix,
1501                              each_ref_fn fn, void *cb_data,
1502                              unsigned int broken)
1503 {
1504         unsigned int flag = 0;
1505
1506         if (broken)
1507                 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1508         return do_for_each_ref(refs, prefix, fn, 0, flag, cb_data);
1509 }
1510
1511 int for_each_replace_ref(struct repository *r, each_repo_ref_fn fn, void *cb_data)
1512 {
1513         return do_for_each_repo_ref(r, git_replace_ref_base, fn,
1514                                     strlen(git_replace_ref_base),
1515                                     DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1516 }
1517
1518 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1519 {
1520         struct strbuf buf = STRBUF_INIT;
1521         int ret;
1522         strbuf_addf(&buf, "%srefs/", get_git_namespace());
1523         ret = do_for_each_ref(get_main_ref_store(the_repository),
1524                               buf.buf, fn, 0, 0, cb_data);
1525         strbuf_release(&buf);
1526         return ret;
1527 }
1528
1529 int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1530 {
1531         return do_for_each_ref(refs, "", fn, 0,
1532                                DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1533 }
1534
1535 int for_each_rawref(each_ref_fn fn, void *cb_data)
1536 {
1537         return refs_for_each_rawref(get_main_ref_store(the_repository), fn, cb_data);
1538 }
1539
1540 int refs_read_raw_ref(struct ref_store *ref_store,
1541                       const char *refname, struct object_id *oid,
1542                       struct strbuf *referent, unsigned int *type)
1543 {
1544         return ref_store->be->read_raw_ref(ref_store, refname, oid, referent, type);
1545 }
1546
1547 /* This function needs to return a meaningful errno on failure */
1548 const char *refs_resolve_ref_unsafe(struct ref_store *refs,
1549                                     const char *refname,
1550                                     int resolve_flags,
1551                                     struct object_id *oid, int *flags)
1552 {
1553         static struct strbuf sb_refname = STRBUF_INIT;
1554         struct object_id unused_oid;
1555         int unused_flags;
1556         int symref_count;
1557
1558         if (!oid)
1559                 oid = &unused_oid;
1560         if (!flags)
1561                 flags = &unused_flags;
1562
1563         *flags = 0;
1564
1565         if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1566                 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1567                     !refname_is_safe(refname)) {
1568                         errno = EINVAL;
1569                         return NULL;
1570                 }
1571
1572                 /*
1573                  * dwim_ref() uses REF_ISBROKEN to distinguish between
1574                  * missing refs and refs that were present but invalid,
1575                  * to complain about the latter to stderr.
1576                  *
1577                  * We don't know whether the ref exists, so don't set
1578                  * REF_ISBROKEN yet.
1579                  */
1580                 *flags |= REF_BAD_NAME;
1581         }
1582
1583         for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1584                 unsigned int read_flags = 0;
1585
1586                 if (refs_read_raw_ref(refs, refname,
1587                                       oid, &sb_refname, &read_flags)) {
1588                         *flags |= read_flags;
1589
1590                         /* In reading mode, refs must eventually resolve */
1591                         if (resolve_flags & RESOLVE_REF_READING)
1592                                 return NULL;
1593
1594                         /*
1595                          * Otherwise a missing ref is OK. But the files backend
1596                          * may show errors besides ENOENT if there are
1597                          * similarly-named refs.
1598                          */
1599                         if (errno != ENOENT &&
1600                             errno != EISDIR &&
1601                             errno != ENOTDIR)
1602                                 return NULL;
1603
1604                         oidclr(oid);
1605                         if (*flags & REF_BAD_NAME)
1606                                 *flags |= REF_ISBROKEN;
1607                         return refname;
1608                 }
1609
1610                 *flags |= read_flags;
1611
1612                 if (!(read_flags & REF_ISSYMREF)) {
1613                         if (*flags & REF_BAD_NAME) {
1614                                 oidclr(oid);
1615                                 *flags |= REF_ISBROKEN;
1616                         }
1617                         return refname;
1618                 }
1619
1620                 refname = sb_refname.buf;
1621                 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1622                         oidclr(oid);
1623                         return refname;
1624                 }
1625                 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1626                         if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1627                             !refname_is_safe(refname)) {
1628                                 errno = EINVAL;
1629                                 return NULL;
1630                         }
1631
1632                         *flags |= REF_ISBROKEN | REF_BAD_NAME;
1633                 }
1634         }
1635
1636         errno = ELOOP;
1637         return NULL;
1638 }
1639
1640 /* backend functions */
1641 int refs_init_db(struct strbuf *err)
1642 {
1643         struct ref_store *refs = get_main_ref_store(the_repository);
1644
1645         return refs->be->init_db(refs, err);
1646 }
1647
1648 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1649                                struct object_id *oid, int *flags)
1650 {
1651         return refs_resolve_ref_unsafe(get_main_ref_store(the_repository), refname,
1652                                        resolve_flags, oid, flags);
1653 }
1654
1655 int resolve_gitlink_ref(const char *submodule, const char *refname,
1656                         struct object_id *oid)
1657 {
1658         struct ref_store *refs;
1659         int flags;
1660
1661         refs = get_submodule_ref_store(submodule);
1662
1663         if (!refs)
1664                 return -1;
1665
1666         if (!refs_resolve_ref_unsafe(refs, refname, 0, oid, &flags) ||
1667             is_null_oid(oid))
1668                 return -1;
1669         return 0;
1670 }
1671
1672 struct ref_store_hash_entry
1673 {
1674         struct hashmap_entry ent; /* must be the first member! */
1675
1676         struct ref_store *refs;
1677
1678         /* NUL-terminated identifier of the ref store: */
1679         char name[FLEX_ARRAY];
1680 };
1681
1682 static int ref_store_hash_cmp(const void *unused_cmp_data,
1683                               const void *entry, const void *entry_or_key,
1684                               const void *keydata)
1685 {
1686         const struct ref_store_hash_entry *e1 = entry, *e2 = entry_or_key;
1687         const char *name = keydata ? keydata : e2->name;
1688
1689         return strcmp(e1->name, name);
1690 }
1691
1692 static struct ref_store_hash_entry *alloc_ref_store_hash_entry(
1693                 const char *name, struct ref_store *refs)
1694 {
1695         struct ref_store_hash_entry *entry;
1696
1697         FLEX_ALLOC_STR(entry, name, name);
1698         hashmap_entry_init(entry, strhash(name));
1699         entry->refs = refs;
1700         return entry;
1701 }
1702
1703 /* A hashmap of ref_stores, stored by submodule name: */
1704 static struct hashmap submodule_ref_stores;
1705
1706 /* A hashmap of ref_stores, stored by worktree id: */
1707 static struct hashmap worktree_ref_stores;
1708
1709 /*
1710  * Look up a ref store by name. If that ref_store hasn't been
1711  * registered yet, return NULL.
1712  */
1713 static struct ref_store *lookup_ref_store_map(struct hashmap *map,
1714                                               const char *name)
1715 {
1716         struct ref_store_hash_entry *entry;
1717
1718         if (!map->tablesize)
1719                 /* It's initialized on demand in register_ref_store(). */
1720                 return NULL;
1721
1722         entry = hashmap_get_from_hash(map, strhash(name), name);
1723         return entry ? entry->refs : NULL;
1724 }
1725
1726 /*
1727  * Create, record, and return a ref_store instance for the specified
1728  * gitdir.
1729  */
1730 static struct ref_store *ref_store_init(const char *gitdir,
1731                                         unsigned int flags)
1732 {
1733         const char *be_name = "files";
1734         struct ref_storage_be *be = find_ref_storage_backend(be_name);
1735         struct ref_store *refs;
1736
1737         if (!be)
1738                 BUG("reference backend %s is unknown", be_name);
1739
1740         refs = be->init(gitdir, flags);
1741         return refs;
1742 }
1743
1744 struct ref_store *get_main_ref_store(struct repository *r)
1745 {
1746         if (r->refs)
1747                 return r->refs;
1748
1749         if (!r->gitdir)
1750                 BUG("attempting to get main_ref_store outside of repository");
1751
1752         r->refs = ref_store_init(r->gitdir, REF_STORE_ALL_CAPS);
1753         return r->refs;
1754 }
1755
1756 /*
1757  * Associate a ref store with a name. It is a fatal error to call this
1758  * function twice for the same name.
1759  */
1760 static void register_ref_store_map(struct hashmap *map,
1761                                    const char *type,
1762                                    struct ref_store *refs,
1763                                    const char *name)
1764 {
1765         if (!map->tablesize)
1766                 hashmap_init(map, ref_store_hash_cmp, NULL, 0);
1767
1768         if (hashmap_put(map, alloc_ref_store_hash_entry(name, refs)))
1769                 BUG("%s ref_store '%s' initialized twice", type, name);
1770 }
1771
1772 struct ref_store *get_submodule_ref_store(const char *submodule)
1773 {
1774         struct strbuf submodule_sb = STRBUF_INIT;
1775         struct ref_store *refs;
1776         char *to_free = NULL;
1777         size_t len;
1778
1779         if (!submodule)
1780                 return NULL;
1781
1782         len = strlen(submodule);
1783         while (len && is_dir_sep(submodule[len - 1]))
1784                 len--;
1785         if (!len)
1786                 return NULL;
1787
1788         if (submodule[len])
1789                 /* We need to strip off one or more trailing slashes */
1790                 submodule = to_free = xmemdupz(submodule, len);
1791
1792         refs = lookup_ref_store_map(&submodule_ref_stores, submodule);
1793         if (refs)
1794                 goto done;
1795
1796         strbuf_addstr(&submodule_sb, submodule);
1797         if (!is_nonbare_repository_dir(&submodule_sb))
1798                 goto done;
1799
1800         if (submodule_to_gitdir(&submodule_sb, submodule))
1801                 goto done;
1802
1803         /* assume that add_submodule_odb() has been called */
1804         refs = ref_store_init(submodule_sb.buf,
1805                               REF_STORE_READ | REF_STORE_ODB);
1806         register_ref_store_map(&submodule_ref_stores, "submodule",
1807                                refs, submodule);
1808
1809 done:
1810         strbuf_release(&submodule_sb);
1811         free(to_free);
1812
1813         return refs;
1814 }
1815
1816 struct ref_store *get_worktree_ref_store(const struct worktree *wt)
1817 {
1818         struct ref_store *refs;
1819         const char *id;
1820
1821         if (wt->is_current)
1822                 return get_main_ref_store(the_repository);
1823
1824         id = wt->id ? wt->id : "/";
1825         refs = lookup_ref_store_map(&worktree_ref_stores, id);
1826         if (refs)
1827                 return refs;
1828
1829         if (wt->id)
1830                 refs = ref_store_init(git_common_path("worktrees/%s", wt->id),
1831                                       REF_STORE_ALL_CAPS);
1832         else
1833                 refs = ref_store_init(get_git_common_dir(),
1834                                       REF_STORE_ALL_CAPS);
1835
1836         if (refs)
1837                 register_ref_store_map(&worktree_ref_stores, "worktree",
1838                                        refs, id);
1839         return refs;
1840 }
1841
1842 void base_ref_store_init(struct ref_store *refs,
1843                          const struct ref_storage_be *be)
1844 {
1845         refs->be = be;
1846 }
1847
1848 /* backend functions */
1849 int refs_pack_refs(struct ref_store *refs, unsigned int flags)
1850 {
1851         return refs->be->pack_refs(refs, flags);
1852 }
1853
1854 int refs_peel_ref(struct ref_store *refs, const char *refname,
1855                   struct object_id *oid)
1856 {
1857         int flag;
1858         struct object_id base;
1859
1860         if (current_ref_iter && current_ref_iter->refname == refname) {
1861                 struct object_id peeled;
1862
1863                 if (ref_iterator_peel(current_ref_iter, &peeled))
1864                         return -1;
1865                 oidcpy(oid, &peeled);
1866                 return 0;
1867         }
1868
1869         if (refs_read_ref_full(refs, refname,
1870                                RESOLVE_REF_READING, &base, &flag))
1871                 return -1;
1872
1873         return peel_object(&base, oid);
1874 }
1875
1876 int peel_ref(const char *refname, struct object_id *oid)
1877 {
1878         return refs_peel_ref(get_main_ref_store(the_repository), refname, oid);
1879 }
1880
1881 int refs_create_symref(struct ref_store *refs,
1882                        const char *ref_target,
1883                        const char *refs_heads_master,
1884                        const char *logmsg)
1885 {
1886         return refs->be->create_symref(refs, ref_target,
1887                                        refs_heads_master,
1888                                        logmsg);
1889 }
1890
1891 int create_symref(const char *ref_target, const char *refs_heads_master,
1892                   const char *logmsg)
1893 {
1894         return refs_create_symref(get_main_ref_store(the_repository), ref_target,
1895                                   refs_heads_master, logmsg);
1896 }
1897
1898 int ref_update_reject_duplicates(struct string_list *refnames,
1899                                  struct strbuf *err)
1900 {
1901         size_t i, n = refnames->nr;
1902
1903         assert(err);
1904
1905         for (i = 1; i < n; i++) {
1906                 int cmp = strcmp(refnames->items[i - 1].string,
1907                                  refnames->items[i].string);
1908
1909                 if (!cmp) {
1910                         strbuf_addf(err,
1911                                     _("multiple updates for ref '%s' not allowed"),
1912                                     refnames->items[i].string);
1913                         return 1;
1914                 } else if (cmp > 0) {
1915                         BUG("ref_update_reject_duplicates() received unsorted list");
1916                 }
1917         }
1918         return 0;
1919 }
1920
1921 int ref_transaction_prepare(struct ref_transaction *transaction,
1922                             struct strbuf *err)
1923 {
1924         struct ref_store *refs = transaction->ref_store;
1925
1926         switch (transaction->state) {
1927         case REF_TRANSACTION_OPEN:
1928                 /* Good. */
1929                 break;
1930         case REF_TRANSACTION_PREPARED:
1931                 BUG("prepare called twice on reference transaction");
1932                 break;
1933         case REF_TRANSACTION_CLOSED:
1934                 BUG("prepare called on a closed reference transaction");
1935                 break;
1936         default:
1937                 BUG("unexpected reference transaction state");
1938                 break;
1939         }
1940
1941         if (getenv(GIT_QUARANTINE_ENVIRONMENT)) {
1942                 strbuf_addstr(err,
1943                               _("ref updates forbidden inside quarantine environment"));
1944                 return -1;
1945         }
1946
1947         return refs->be->transaction_prepare(refs, transaction, err);
1948 }
1949
1950 int ref_transaction_abort(struct ref_transaction *transaction,
1951                           struct strbuf *err)
1952 {
1953         struct ref_store *refs = transaction->ref_store;
1954         int ret = 0;
1955
1956         switch (transaction->state) {
1957         case REF_TRANSACTION_OPEN:
1958                 /* No need to abort explicitly. */
1959                 break;
1960         case REF_TRANSACTION_PREPARED:
1961                 ret = refs->be->transaction_abort(refs, transaction, err);
1962                 break;
1963         case REF_TRANSACTION_CLOSED:
1964                 BUG("abort called on a closed reference transaction");
1965                 break;
1966         default:
1967                 BUG("unexpected reference transaction state");
1968                 break;
1969         }
1970
1971         ref_transaction_free(transaction);
1972         return ret;
1973 }
1974
1975 int ref_transaction_commit(struct ref_transaction *transaction,
1976                            struct strbuf *err)
1977 {
1978         struct ref_store *refs = transaction->ref_store;
1979         int ret;
1980
1981         switch (transaction->state) {
1982         case REF_TRANSACTION_OPEN:
1983                 /* Need to prepare first. */
1984                 ret = ref_transaction_prepare(transaction, err);
1985                 if (ret)
1986                         return ret;
1987                 break;
1988         case REF_TRANSACTION_PREPARED:
1989                 /* Fall through to finish. */
1990                 break;
1991         case REF_TRANSACTION_CLOSED:
1992                 BUG("commit called on a closed reference transaction");
1993                 break;
1994         default:
1995                 BUG("unexpected reference transaction state");
1996                 break;
1997         }
1998
1999         return refs->be->transaction_finish(refs, transaction, err);
2000 }
2001
2002 int refs_verify_refname_available(struct ref_store *refs,
2003                                   const char *refname,
2004                                   const struct string_list *extras,
2005                                   const struct string_list *skip,
2006                                   struct strbuf *err)
2007 {
2008         const char *slash;
2009         const char *extra_refname;
2010         struct strbuf dirname = STRBUF_INIT;
2011         struct strbuf referent = STRBUF_INIT;
2012         struct object_id oid;
2013         unsigned int type;
2014         struct ref_iterator *iter;
2015         int ok;
2016         int ret = -1;
2017
2018         /*
2019          * For the sake of comments in this function, suppose that
2020          * refname is "refs/foo/bar".
2021          */
2022
2023         assert(err);
2024
2025         strbuf_grow(&dirname, strlen(refname) + 1);
2026         for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
2027                 /* Expand dirname to the new prefix, not including the trailing slash: */
2028                 strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
2029
2030                 /*
2031                  * We are still at a leading dir of the refname (e.g.,
2032                  * "refs/foo"; if there is a reference with that name,
2033                  * it is a conflict, *unless* it is in skip.
2034                  */
2035                 if (skip && string_list_has_string(skip, dirname.buf))
2036                         continue;
2037
2038                 if (!refs_read_raw_ref(refs, dirname.buf, &oid, &referent, &type)) {
2039                         strbuf_addf(err, _("'%s' exists; cannot create '%s'"),
2040                                     dirname.buf, refname);
2041                         goto cleanup;
2042                 }
2043
2044                 if (extras && string_list_has_string(extras, dirname.buf)) {
2045                         strbuf_addf(err, _("cannot process '%s' and '%s' at the same time"),
2046                                     refname, dirname.buf);
2047                         goto cleanup;
2048                 }
2049         }
2050
2051         /*
2052          * We are at the leaf of our refname (e.g., "refs/foo/bar").
2053          * There is no point in searching for a reference with that
2054          * name, because a refname isn't considered to conflict with
2055          * itself. But we still need to check for references whose
2056          * names are in the "refs/foo/bar/" namespace, because they
2057          * *do* conflict.
2058          */
2059         strbuf_addstr(&dirname, refname + dirname.len);
2060         strbuf_addch(&dirname, '/');
2061
2062         iter = refs_ref_iterator_begin(refs, dirname.buf, 0,
2063                                        DO_FOR_EACH_INCLUDE_BROKEN);
2064         while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
2065                 if (skip &&
2066                     string_list_has_string(skip, iter->refname))
2067                         continue;
2068
2069                 strbuf_addf(err, _("'%s' exists; cannot create '%s'"),
2070                             iter->refname, refname);
2071                 ref_iterator_abort(iter);
2072                 goto cleanup;
2073         }
2074
2075         if (ok != ITER_DONE)
2076                 BUG("error while iterating over references");
2077
2078         extra_refname = find_descendant_ref(dirname.buf, extras, skip);
2079         if (extra_refname)
2080                 strbuf_addf(err, _("cannot process '%s' and '%s' at the same time"),
2081                             refname, extra_refname);
2082         else
2083                 ret = 0;
2084
2085 cleanup:
2086         strbuf_release(&referent);
2087         strbuf_release(&dirname);
2088         return ret;
2089 }
2090
2091 int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2092 {
2093         struct ref_iterator *iter;
2094         struct do_for_each_ref_help hp = { fn, cb_data };
2095
2096         iter = refs->be->reflog_iterator_begin(refs);
2097
2098         return do_for_each_repo_ref_iterator(the_repository, iter,
2099                                              do_for_each_ref_helper, &hp);
2100 }
2101
2102 int for_each_reflog(each_ref_fn fn, void *cb_data)
2103 {
2104         return refs_for_each_reflog(get_main_ref_store(the_repository), fn, cb_data);
2105 }
2106
2107 int refs_for_each_reflog_ent_reverse(struct ref_store *refs,
2108                                      const char *refname,
2109                                      each_reflog_ent_fn fn,
2110                                      void *cb_data)
2111 {
2112         return refs->be->for_each_reflog_ent_reverse(refs, refname,
2113                                                      fn, cb_data);
2114 }
2115
2116 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
2117                                 void *cb_data)
2118 {
2119         return refs_for_each_reflog_ent_reverse(get_main_ref_store(the_repository),
2120                                                 refname, fn, cb_data);
2121 }
2122
2123 int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname,
2124                              each_reflog_ent_fn fn, void *cb_data)
2125 {
2126         return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
2127 }
2128
2129 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
2130                         void *cb_data)
2131 {
2132         return refs_for_each_reflog_ent(get_main_ref_store(the_repository), refname,
2133                                         fn, cb_data);
2134 }
2135
2136 int refs_reflog_exists(struct ref_store *refs, const char *refname)
2137 {
2138         return refs->be->reflog_exists(refs, refname);
2139 }
2140
2141 int reflog_exists(const char *refname)
2142 {
2143         return refs_reflog_exists(get_main_ref_store(the_repository), refname);
2144 }
2145
2146 int refs_create_reflog(struct ref_store *refs, const char *refname,
2147                        int force_create, struct strbuf *err)
2148 {
2149         return refs->be->create_reflog(refs, refname, force_create, err);
2150 }
2151
2152 int safe_create_reflog(const char *refname, int force_create,
2153                        struct strbuf *err)
2154 {
2155         return refs_create_reflog(get_main_ref_store(the_repository), refname,
2156                                   force_create, err);
2157 }
2158
2159 int refs_delete_reflog(struct ref_store *refs, const char *refname)
2160 {
2161         return refs->be->delete_reflog(refs, refname);
2162 }
2163
2164 int delete_reflog(const char *refname)
2165 {
2166         return refs_delete_reflog(get_main_ref_store(the_repository), refname);
2167 }
2168
2169 int refs_reflog_expire(struct ref_store *refs,
2170                        const char *refname, const struct object_id *oid,
2171                        unsigned int flags,
2172                        reflog_expiry_prepare_fn prepare_fn,
2173                        reflog_expiry_should_prune_fn should_prune_fn,
2174                        reflog_expiry_cleanup_fn cleanup_fn,
2175                        void *policy_cb_data)
2176 {
2177         return refs->be->reflog_expire(refs, refname, oid, flags,
2178                                        prepare_fn, should_prune_fn,
2179                                        cleanup_fn, policy_cb_data);
2180 }
2181
2182 int reflog_expire(const char *refname, const struct object_id *oid,
2183                   unsigned int flags,
2184                   reflog_expiry_prepare_fn prepare_fn,
2185                   reflog_expiry_should_prune_fn should_prune_fn,
2186                   reflog_expiry_cleanup_fn cleanup_fn,
2187                   void *policy_cb_data)
2188 {
2189         return refs_reflog_expire(get_main_ref_store(the_repository),
2190                                   refname, oid, flags,
2191                                   prepare_fn, should_prune_fn,
2192                                   cleanup_fn, policy_cb_data);
2193 }
2194
2195 int initial_ref_transaction_commit(struct ref_transaction *transaction,
2196                                    struct strbuf *err)
2197 {
2198         struct ref_store *refs = transaction->ref_store;
2199
2200         return refs->be->initial_transaction_commit(refs, transaction, err);
2201 }
2202
2203 int refs_delete_refs(struct ref_store *refs, const char *msg,
2204                      struct string_list *refnames, unsigned int flags)
2205 {
2206         return refs->be->delete_refs(refs, msg, refnames, flags);
2207 }
2208
2209 int delete_refs(const char *msg, struct string_list *refnames,
2210                 unsigned int flags)
2211 {
2212         return refs_delete_refs(get_main_ref_store(the_repository), msg, refnames, flags);
2213 }
2214
2215 int refs_rename_ref(struct ref_store *refs, const char *oldref,
2216                     const char *newref, const char *logmsg)
2217 {
2218         return refs->be->rename_ref(refs, oldref, newref, logmsg);
2219 }
2220
2221 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
2222 {
2223         return refs_rename_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2224 }
2225
2226 int refs_copy_existing_ref(struct ref_store *refs, const char *oldref,
2227                     const char *newref, const char *logmsg)
2228 {
2229         return refs->be->copy_ref(refs, oldref, newref, logmsg);
2230 }
2231
2232 int copy_existing_ref(const char *oldref, const char *newref, const char *logmsg)
2233 {
2234         return refs_copy_existing_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2235 }