Merge branch 'js/mingw-isatty'
[git] / refs.c
1 /*
2  * The backend-independent part of the reference module.
3  */
4
5 #include "cache.h"
6 #include "lockfile.h"
7 #include "refs.h"
8 #include "refs/refs-internal.h"
9 #include "object.h"
10 #include "tag.h"
11
12 /*
13  * List of all available backends
14  */
15 static struct ref_storage_be *refs_backends = &refs_be_files;
16
17 static struct ref_storage_be *find_ref_storage_backend(const char *name)
18 {
19         struct ref_storage_be *be;
20         for (be = refs_backends; be; be = be->next)
21                 if (!strcmp(be->name, name))
22                         return be;
23         return NULL;
24 }
25
26 int ref_storage_backend_exists(const char *name)
27 {
28         return find_ref_storage_backend(name) != NULL;
29 }
30
31 /*
32  * How to handle various characters in refnames:
33  * 0: An acceptable character for refs
34  * 1: End-of-component
35  * 2: ., look for a preceding . to reject .. in refs
36  * 3: {, look for a preceding @ to reject @{ in refs
37  * 4: A bad character: ASCII control characters, and
38  *    ":", "?", "[", "\", "^", "~", SP, or TAB
39  * 5: *, reject unless REFNAME_REFSPEC_PATTERN is set
40  */
41 static unsigned char refname_disposition[256] = {
42         1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
43         4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
44         4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 2, 1,
45         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4,
46         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
47         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 4, 0,
48         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
49         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 4
50 };
51
52 /*
53  * Try to read one refname component from the front of refname.
54  * Return the length of the component found, or -1 if the component is
55  * not legal.  It is legal if it is something reasonable to have under
56  * ".git/refs/"; We do not like it if:
57  *
58  * - any path component of it begins with ".", or
59  * - it has double dots "..", or
60  * - it has ASCII control characters, or
61  * - it has ":", "?", "[", "\", "^", "~", SP, or TAB anywhere, or
62  * - it has "*" anywhere unless REFNAME_REFSPEC_PATTERN is set, or
63  * - it ends with a "/", or
64  * - it ends with ".lock", or
65  * - it contains a "@{" portion
66  */
67 static int check_refname_component(const char *refname, int *flags)
68 {
69         const char *cp;
70         char last = '\0';
71
72         for (cp = refname; ; cp++) {
73                 int ch = *cp & 255;
74                 unsigned char disp = refname_disposition[ch];
75                 switch (disp) {
76                 case 1:
77                         goto out;
78                 case 2:
79                         if (last == '.')
80                                 return -1; /* Refname contains "..". */
81                         break;
82                 case 3:
83                         if (last == '@')
84                                 return -1; /* Refname contains "@{". */
85                         break;
86                 case 4:
87                         return -1;
88                 case 5:
89                         if (!(*flags & REFNAME_REFSPEC_PATTERN))
90                                 return -1; /* refspec can't be a pattern */
91
92                         /*
93                          * Unset the pattern flag so that we only accept
94                          * a single asterisk for one side of refspec.
95                          */
96                         *flags &= ~ REFNAME_REFSPEC_PATTERN;
97                         break;
98                 }
99                 last = ch;
100         }
101 out:
102         if (cp == refname)
103                 return 0; /* Component has zero length. */
104         if (refname[0] == '.')
105                 return -1; /* Component starts with '.'. */
106         if (cp - refname >= LOCK_SUFFIX_LEN &&
107             !memcmp(cp - LOCK_SUFFIX_LEN, LOCK_SUFFIX, LOCK_SUFFIX_LEN))
108                 return -1; /* Refname ends with ".lock". */
109         return cp - refname;
110 }
111
112 int check_refname_format(const char *refname, int flags)
113 {
114         int component_len, component_count = 0;
115
116         if (!strcmp(refname, "@"))
117                 /* Refname is a single character '@'. */
118                 return -1;
119
120         while (1) {
121                 /* We are at the start of a path component. */
122                 component_len = check_refname_component(refname, &flags);
123                 if (component_len <= 0)
124                         return -1;
125
126                 component_count++;
127                 if (refname[component_len] == '\0')
128                         break;
129                 /* Skip to next component. */
130                 refname += component_len + 1;
131         }
132
133         if (refname[component_len - 1] == '.')
134                 return -1; /* Refname ends with '.'. */
135         if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
136                 return -1; /* Refname has only one component. */
137         return 0;
138 }
139
140 int refname_is_safe(const char *refname)
141 {
142         const char *rest;
143
144         if (skip_prefix(refname, "refs/", &rest)) {
145                 char *buf;
146                 int result;
147                 size_t restlen = strlen(rest);
148
149                 /* rest must not be empty, or start or end with "/" */
150                 if (!restlen || *rest == '/' || rest[restlen - 1] == '/')
151                         return 0;
152
153                 /*
154                  * Does the refname try to escape refs/?
155                  * For example: refs/foo/../bar is safe but refs/foo/../../bar
156                  * is not.
157                  */
158                 buf = xmallocz(restlen);
159                 result = !normalize_path_copy(buf, rest) && !strcmp(buf, rest);
160                 free(buf);
161                 return result;
162         }
163
164         do {
165                 if (!isupper(*refname) && *refname != '_')
166                         return 0;
167                 refname++;
168         } while (*refname);
169         return 1;
170 }
171
172 char *resolve_refdup(const char *refname, int resolve_flags,
173                      unsigned char *sha1, int *flags)
174 {
175         return xstrdup_or_null(resolve_ref_unsafe(refname, resolve_flags,
176                                                   sha1, flags));
177 }
178
179 /* The argument to filter_refs */
180 struct ref_filter {
181         const char *pattern;
182         each_ref_fn *fn;
183         void *cb_data;
184 };
185
186 int read_ref_full(const char *refname, int resolve_flags, unsigned char *sha1, int *flags)
187 {
188         if (resolve_ref_unsafe(refname, resolve_flags, sha1, flags))
189                 return 0;
190         return -1;
191 }
192
193 int read_ref(const char *refname, unsigned char *sha1)
194 {
195         return read_ref_full(refname, RESOLVE_REF_READING, sha1, NULL);
196 }
197
198 int ref_exists(const char *refname)
199 {
200         unsigned char sha1[20];
201         return !!resolve_ref_unsafe(refname, RESOLVE_REF_READING, sha1, NULL);
202 }
203
204 static int filter_refs(const char *refname, const struct object_id *oid,
205                            int flags, void *data)
206 {
207         struct ref_filter *filter = (struct ref_filter *)data;
208
209         if (wildmatch(filter->pattern, refname, 0, NULL))
210                 return 0;
211         return filter->fn(refname, oid, flags, filter->cb_data);
212 }
213
214 enum peel_status peel_object(const unsigned char *name, unsigned char *sha1)
215 {
216         struct object *o = lookup_unknown_object(name);
217
218         if (o->type == OBJ_NONE) {
219                 int type = sha1_object_info(name, NULL);
220                 if (type < 0 || !object_as_type(o, type, 0))
221                         return PEEL_INVALID;
222         }
223
224         if (o->type != OBJ_TAG)
225                 return PEEL_NON_TAG;
226
227         o = deref_tag_noverify(o);
228         if (!o)
229                 return PEEL_INVALID;
230
231         hashcpy(sha1, o->oid.hash);
232         return PEEL_PEELED;
233 }
234
235 struct warn_if_dangling_data {
236         FILE *fp;
237         const char *refname;
238         const struct string_list *refnames;
239         const char *msg_fmt;
240 };
241
242 static int warn_if_dangling_symref(const char *refname, const struct object_id *oid,
243                                    int flags, void *cb_data)
244 {
245         struct warn_if_dangling_data *d = cb_data;
246         const char *resolves_to;
247         struct object_id junk;
248
249         if (!(flags & REF_ISSYMREF))
250                 return 0;
251
252         resolves_to = resolve_ref_unsafe(refname, 0, junk.hash, NULL);
253         if (!resolves_to
254             || (d->refname
255                 ? strcmp(resolves_to, d->refname)
256                 : !string_list_has_string(d->refnames, resolves_to))) {
257                 return 0;
258         }
259
260         fprintf(d->fp, d->msg_fmt, refname);
261         fputc('\n', d->fp);
262         return 0;
263 }
264
265 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
266 {
267         struct warn_if_dangling_data data;
268
269         data.fp = fp;
270         data.refname = refname;
271         data.refnames = NULL;
272         data.msg_fmt = msg_fmt;
273         for_each_rawref(warn_if_dangling_symref, &data);
274 }
275
276 void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames)
277 {
278         struct warn_if_dangling_data data;
279
280         data.fp = fp;
281         data.refname = NULL;
282         data.refnames = refnames;
283         data.msg_fmt = msg_fmt;
284         for_each_rawref(warn_if_dangling_symref, &data);
285 }
286
287 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
288 {
289         return for_each_ref_in("refs/tags/", fn, cb_data);
290 }
291
292 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
293 {
294         return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
295 }
296
297 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
298 {
299         return for_each_ref_in("refs/heads/", fn, cb_data);
300 }
301
302 int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
303 {
304         return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
305 }
306
307 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
308 {
309         return for_each_ref_in("refs/remotes/", fn, cb_data);
310 }
311
312 int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
313 {
314         return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
315 }
316
317 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
318 {
319         struct strbuf buf = STRBUF_INIT;
320         int ret = 0;
321         struct object_id oid;
322         int flag;
323
324         strbuf_addf(&buf, "%sHEAD", get_git_namespace());
325         if (!read_ref_full(buf.buf, RESOLVE_REF_READING, oid.hash, &flag))
326                 ret = fn(buf.buf, &oid, flag, cb_data);
327         strbuf_release(&buf);
328
329         return ret;
330 }
331
332 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
333         const char *prefix, void *cb_data)
334 {
335         struct strbuf real_pattern = STRBUF_INIT;
336         struct ref_filter filter;
337         int ret;
338
339         if (!prefix && !starts_with(pattern, "refs/"))
340                 strbuf_addstr(&real_pattern, "refs/");
341         else if (prefix)
342                 strbuf_addstr(&real_pattern, prefix);
343         strbuf_addstr(&real_pattern, pattern);
344
345         if (!has_glob_specials(pattern)) {
346                 /* Append implied '/' '*' if not present. */
347                 strbuf_complete(&real_pattern, '/');
348                 /* No need to check for '*', there is none. */
349                 strbuf_addch(&real_pattern, '*');
350         }
351
352         filter.pattern = real_pattern.buf;
353         filter.fn = fn;
354         filter.cb_data = cb_data;
355         ret = for_each_ref(filter_refs, &filter);
356
357         strbuf_release(&real_pattern);
358         return ret;
359 }
360
361 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
362 {
363         return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
364 }
365
366 const char *prettify_refname(const char *name)
367 {
368         return name + (
369                 starts_with(name, "refs/heads/") ? 11 :
370                 starts_with(name, "refs/tags/") ? 10 :
371                 starts_with(name, "refs/remotes/") ? 13 :
372                 0);
373 }
374
375 static const char *ref_rev_parse_rules[] = {
376         "%.*s",
377         "refs/%.*s",
378         "refs/tags/%.*s",
379         "refs/heads/%.*s",
380         "refs/remotes/%.*s",
381         "refs/remotes/%.*s/HEAD",
382         NULL
383 };
384
385 int refname_match(const char *abbrev_name, const char *full_name)
386 {
387         const char **p;
388         const int abbrev_name_len = strlen(abbrev_name);
389
390         for (p = ref_rev_parse_rules; *p; p++) {
391                 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
392                         return 1;
393                 }
394         }
395
396         return 0;
397 }
398
399 /*
400  * *string and *len will only be substituted, and *string returned (for
401  * later free()ing) if the string passed in is a magic short-hand form
402  * to name a branch.
403  */
404 static char *substitute_branch_name(const char **string, int *len)
405 {
406         struct strbuf buf = STRBUF_INIT;
407         int ret = interpret_branch_name(*string, *len, &buf);
408
409         if (ret == *len) {
410                 size_t size;
411                 *string = strbuf_detach(&buf, &size);
412                 *len = size;
413                 return (char *)*string;
414         }
415
416         return NULL;
417 }
418
419 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
420 {
421         char *last_branch = substitute_branch_name(&str, &len);
422         int   refs_found  = expand_ref(str, len, sha1, ref);
423         free(last_branch);
424         return refs_found;
425 }
426
427 int expand_ref(const char *str, int len, unsigned char *sha1, char **ref)
428 {
429         const char **p, *r;
430         int refs_found = 0;
431
432         *ref = NULL;
433         for (p = ref_rev_parse_rules; *p; p++) {
434                 char fullref[PATH_MAX];
435                 unsigned char sha1_from_ref[20];
436                 unsigned char *this_result;
437                 int flag;
438
439                 this_result = refs_found ? sha1_from_ref : sha1;
440                 mksnpath(fullref, sizeof(fullref), *p, len, str);
441                 r = resolve_ref_unsafe(fullref, RESOLVE_REF_READING,
442                                        this_result, &flag);
443                 if (r) {
444                         if (!refs_found++)
445                                 *ref = xstrdup(r);
446                         if (!warn_ambiguous_refs)
447                                 break;
448                 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
449                         warning("ignoring dangling symref %s.", fullref);
450                 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
451                         warning("ignoring broken ref %s.", fullref);
452                 }
453         }
454         return refs_found;
455 }
456
457 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
458 {
459         char *last_branch = substitute_branch_name(&str, &len);
460         const char **p;
461         int logs_found = 0;
462
463         *log = NULL;
464         for (p = ref_rev_parse_rules; *p; p++) {
465                 unsigned char hash[20];
466                 char path[PATH_MAX];
467                 const char *ref, *it;
468
469                 mksnpath(path, sizeof(path), *p, len, str);
470                 ref = resolve_ref_unsafe(path, RESOLVE_REF_READING,
471                                          hash, NULL);
472                 if (!ref)
473                         continue;
474                 if (reflog_exists(path))
475                         it = path;
476                 else if (strcmp(ref, path) && reflog_exists(ref))
477                         it = ref;
478                 else
479                         continue;
480                 if (!logs_found++) {
481                         *log = xstrdup(it);
482                         hashcpy(sha1, hash);
483                 }
484                 if (!warn_ambiguous_refs)
485                         break;
486         }
487         free(last_branch);
488         return logs_found;
489 }
490
491 static int is_per_worktree_ref(const char *refname)
492 {
493         return !strcmp(refname, "HEAD") ||
494                 starts_with(refname, "refs/bisect/");
495 }
496
497 static int is_pseudoref_syntax(const char *refname)
498 {
499         const char *c;
500
501         for (c = refname; *c; c++) {
502                 if (!isupper(*c) && *c != '-' && *c != '_')
503                         return 0;
504         }
505
506         return 1;
507 }
508
509 enum ref_type ref_type(const char *refname)
510 {
511         if (is_per_worktree_ref(refname))
512                 return REF_TYPE_PER_WORKTREE;
513         if (is_pseudoref_syntax(refname))
514                 return REF_TYPE_PSEUDOREF;
515        return REF_TYPE_NORMAL;
516 }
517
518 static int write_pseudoref(const char *pseudoref, const unsigned char *sha1,
519                            const unsigned char *old_sha1, struct strbuf *err)
520 {
521         const char *filename;
522         int fd;
523         static struct lock_file lock;
524         struct strbuf buf = STRBUF_INIT;
525         int ret = -1;
526
527         strbuf_addf(&buf, "%s\n", sha1_to_hex(sha1));
528
529         filename = git_path("%s", pseudoref);
530         fd = hold_lock_file_for_update(&lock, filename, LOCK_DIE_ON_ERROR);
531         if (fd < 0) {
532                 strbuf_addf(err, "could not open '%s' for writing: %s",
533                             filename, strerror(errno));
534                 return -1;
535         }
536
537         if (old_sha1) {
538                 unsigned char actual_old_sha1[20];
539
540                 if (read_ref(pseudoref, actual_old_sha1))
541                         die("could not read ref '%s'", pseudoref);
542                 if (hashcmp(actual_old_sha1, old_sha1)) {
543                         strbuf_addf(err, "unexpected sha1 when writing '%s'", pseudoref);
544                         rollback_lock_file(&lock);
545                         goto done;
546                 }
547         }
548
549         if (write_in_full(fd, buf.buf, buf.len) != buf.len) {
550                 strbuf_addf(err, "could not write to '%s'", filename);
551                 rollback_lock_file(&lock);
552                 goto done;
553         }
554
555         commit_lock_file(&lock);
556         ret = 0;
557 done:
558         strbuf_release(&buf);
559         return ret;
560 }
561
562 static int delete_pseudoref(const char *pseudoref, const unsigned char *old_sha1)
563 {
564         static struct lock_file lock;
565         const char *filename;
566
567         filename = git_path("%s", pseudoref);
568
569         if (old_sha1 && !is_null_sha1(old_sha1)) {
570                 int fd;
571                 unsigned char actual_old_sha1[20];
572
573                 fd = hold_lock_file_for_update(&lock, filename,
574                                                LOCK_DIE_ON_ERROR);
575                 if (fd < 0)
576                         die_errno(_("Could not open '%s' for writing"), filename);
577                 if (read_ref(pseudoref, actual_old_sha1))
578                         die("could not read ref '%s'", pseudoref);
579                 if (hashcmp(actual_old_sha1, old_sha1)) {
580                         warning("Unexpected sha1 when deleting %s", pseudoref);
581                         rollback_lock_file(&lock);
582                         return -1;
583                 }
584
585                 unlink(filename);
586                 rollback_lock_file(&lock);
587         } else {
588                 unlink(filename);
589         }
590
591         return 0;
592 }
593
594 int delete_ref(const char *refname, const unsigned char *old_sha1,
595                unsigned int flags)
596 {
597         struct ref_transaction *transaction;
598         struct strbuf err = STRBUF_INIT;
599
600         if (ref_type(refname) == REF_TYPE_PSEUDOREF)
601                 return delete_pseudoref(refname, old_sha1);
602
603         transaction = ref_transaction_begin(&err);
604         if (!transaction ||
605             ref_transaction_delete(transaction, refname, old_sha1,
606                                    flags, NULL, &err) ||
607             ref_transaction_commit(transaction, &err)) {
608                 error("%s", err.buf);
609                 ref_transaction_free(transaction);
610                 strbuf_release(&err);
611                 return 1;
612         }
613         ref_transaction_free(transaction);
614         strbuf_release(&err);
615         return 0;
616 }
617
618 int copy_reflog_msg(char *buf, const char *msg)
619 {
620         char *cp = buf;
621         char c;
622         int wasspace = 1;
623
624         *cp++ = '\t';
625         while ((c = *msg++)) {
626                 if (wasspace && isspace(c))
627                         continue;
628                 wasspace = isspace(c);
629                 if (wasspace)
630                         c = ' ';
631                 *cp++ = c;
632         }
633         while (buf < cp && isspace(cp[-1]))
634                 cp--;
635         *cp++ = '\n';
636         return cp - buf;
637 }
638
639 int should_autocreate_reflog(const char *refname)
640 {
641         switch (log_all_ref_updates) {
642         case LOG_REFS_ALWAYS:
643                 return 1;
644         case LOG_REFS_NORMAL:
645                 return starts_with(refname, "refs/heads/") ||
646                         starts_with(refname, "refs/remotes/") ||
647                         starts_with(refname, "refs/notes/") ||
648                         !strcmp(refname, "HEAD");
649         default:
650                 return 0;
651         }
652 }
653
654 int is_branch(const char *refname)
655 {
656         return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
657 }
658
659 struct read_ref_at_cb {
660         const char *refname;
661         unsigned long at_time;
662         int cnt;
663         int reccnt;
664         unsigned char *sha1;
665         int found_it;
666
667         unsigned char osha1[20];
668         unsigned char nsha1[20];
669         int tz;
670         unsigned long date;
671         char **msg;
672         unsigned long *cutoff_time;
673         int *cutoff_tz;
674         int *cutoff_cnt;
675 };
676
677 static int read_ref_at_ent(unsigned char *osha1, unsigned char *nsha1,
678                 const char *email, unsigned long timestamp, int tz,
679                 const char *message, void *cb_data)
680 {
681         struct read_ref_at_cb *cb = cb_data;
682
683         cb->reccnt++;
684         cb->tz = tz;
685         cb->date = timestamp;
686
687         if (timestamp <= cb->at_time || cb->cnt == 0) {
688                 if (cb->msg)
689                         *cb->msg = xstrdup(message);
690                 if (cb->cutoff_time)
691                         *cb->cutoff_time = timestamp;
692                 if (cb->cutoff_tz)
693                         *cb->cutoff_tz = tz;
694                 if (cb->cutoff_cnt)
695                         *cb->cutoff_cnt = cb->reccnt - 1;
696                 /*
697                  * we have not yet updated cb->[n|o]sha1 so they still
698                  * hold the values for the previous record.
699                  */
700                 if (!is_null_sha1(cb->osha1)) {
701                         hashcpy(cb->sha1, nsha1);
702                         if (hashcmp(cb->osha1, nsha1))
703                                 warning("Log for ref %s has gap after %s.",
704                                         cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
705                 }
706                 else if (cb->date == cb->at_time)
707                         hashcpy(cb->sha1, nsha1);
708                 else if (hashcmp(nsha1, cb->sha1))
709                         warning("Log for ref %s unexpectedly ended on %s.",
710                                 cb->refname, show_date(cb->date, cb->tz,
711                                                        DATE_MODE(RFC2822)));
712                 hashcpy(cb->osha1, osha1);
713                 hashcpy(cb->nsha1, nsha1);
714                 cb->found_it = 1;
715                 return 1;
716         }
717         hashcpy(cb->osha1, osha1);
718         hashcpy(cb->nsha1, nsha1);
719         if (cb->cnt > 0)
720                 cb->cnt--;
721         return 0;
722 }
723
724 static int read_ref_at_ent_oldest(unsigned char *osha1, unsigned char *nsha1,
725                                   const char *email, unsigned long timestamp,
726                                   int tz, const char *message, void *cb_data)
727 {
728         struct read_ref_at_cb *cb = cb_data;
729
730         if (cb->msg)
731                 *cb->msg = xstrdup(message);
732         if (cb->cutoff_time)
733                 *cb->cutoff_time = timestamp;
734         if (cb->cutoff_tz)
735                 *cb->cutoff_tz = tz;
736         if (cb->cutoff_cnt)
737                 *cb->cutoff_cnt = cb->reccnt;
738         hashcpy(cb->sha1, osha1);
739         if (is_null_sha1(cb->sha1))
740                 hashcpy(cb->sha1, nsha1);
741         /* We just want the first entry */
742         return 1;
743 }
744
745 int read_ref_at(const char *refname, unsigned int flags, unsigned long at_time, int cnt,
746                 unsigned char *sha1, char **msg,
747                 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
748 {
749         struct read_ref_at_cb cb;
750
751         memset(&cb, 0, sizeof(cb));
752         cb.refname = refname;
753         cb.at_time = at_time;
754         cb.cnt = cnt;
755         cb.msg = msg;
756         cb.cutoff_time = cutoff_time;
757         cb.cutoff_tz = cutoff_tz;
758         cb.cutoff_cnt = cutoff_cnt;
759         cb.sha1 = sha1;
760
761         for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
762
763         if (!cb.reccnt) {
764                 if (flags & GET_SHA1_QUIETLY)
765                         exit(128);
766                 else
767                         die("Log for %s is empty.", refname);
768         }
769         if (cb.found_it)
770                 return 0;
771
772         for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
773
774         return 1;
775 }
776
777 struct ref_transaction *ref_transaction_begin(struct strbuf *err)
778 {
779         assert(err);
780
781         return xcalloc(1, sizeof(struct ref_transaction));
782 }
783
784 void ref_transaction_free(struct ref_transaction *transaction)
785 {
786         int i;
787
788         if (!transaction)
789                 return;
790
791         for (i = 0; i < transaction->nr; i++) {
792                 free(transaction->updates[i]->msg);
793                 free(transaction->updates[i]);
794         }
795         free(transaction->updates);
796         free(transaction);
797 }
798
799 struct ref_update *ref_transaction_add_update(
800                 struct ref_transaction *transaction,
801                 const char *refname, unsigned int flags,
802                 const unsigned char *new_sha1,
803                 const unsigned char *old_sha1,
804                 const char *msg)
805 {
806         struct ref_update *update;
807
808         if (transaction->state != REF_TRANSACTION_OPEN)
809                 die("BUG: update called for transaction that is not open");
810
811         if ((flags & REF_ISPRUNING) && !(flags & REF_NODEREF))
812                 die("BUG: REF_ISPRUNING set without REF_NODEREF");
813
814         FLEX_ALLOC_STR(update, refname, refname);
815         ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
816         transaction->updates[transaction->nr++] = update;
817
818         update->flags = flags;
819
820         if (flags & REF_HAVE_NEW)
821                 hashcpy(update->new_sha1, new_sha1);
822         if (flags & REF_HAVE_OLD)
823                 hashcpy(update->old_sha1, old_sha1);
824         update->msg = xstrdup_or_null(msg);
825         return update;
826 }
827
828 int ref_transaction_update(struct ref_transaction *transaction,
829                            const char *refname,
830                            const unsigned char *new_sha1,
831                            const unsigned char *old_sha1,
832                            unsigned int flags, const char *msg,
833                            struct strbuf *err)
834 {
835         assert(err);
836
837         if ((new_sha1 && !is_null_sha1(new_sha1)) ?
838             check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
839             !refname_is_safe(refname)) {
840                 strbuf_addf(err, "refusing to update ref with bad name '%s'",
841                             refname);
842                 return -1;
843         }
844
845         flags |= (new_sha1 ? REF_HAVE_NEW : 0) | (old_sha1 ? REF_HAVE_OLD : 0);
846
847         ref_transaction_add_update(transaction, refname, flags,
848                                    new_sha1, old_sha1, msg);
849         return 0;
850 }
851
852 int ref_transaction_create(struct ref_transaction *transaction,
853                            const char *refname,
854                            const unsigned char *new_sha1,
855                            unsigned int flags, const char *msg,
856                            struct strbuf *err)
857 {
858         if (!new_sha1 || is_null_sha1(new_sha1))
859                 die("BUG: create called without valid new_sha1");
860         return ref_transaction_update(transaction, refname, new_sha1,
861                                       null_sha1, flags, msg, err);
862 }
863
864 int ref_transaction_delete(struct ref_transaction *transaction,
865                            const char *refname,
866                            const unsigned char *old_sha1,
867                            unsigned int flags, const char *msg,
868                            struct strbuf *err)
869 {
870         if (old_sha1 && is_null_sha1(old_sha1))
871                 die("BUG: delete called with old_sha1 set to zeros");
872         return ref_transaction_update(transaction, refname,
873                                       null_sha1, old_sha1,
874                                       flags, msg, err);
875 }
876
877 int ref_transaction_verify(struct ref_transaction *transaction,
878                            const char *refname,
879                            const unsigned char *old_sha1,
880                            unsigned int flags,
881                            struct strbuf *err)
882 {
883         if (!old_sha1)
884                 die("BUG: verify called with old_sha1 set to NULL");
885         return ref_transaction_update(transaction, refname,
886                                       NULL, old_sha1,
887                                       flags, NULL, err);
888 }
889
890 int update_ref_oid(const char *msg, const char *refname,
891                const struct object_id *new_oid, const struct object_id *old_oid,
892                unsigned int flags, enum action_on_err onerr)
893 {
894         return update_ref(msg, refname, new_oid ? new_oid->hash : NULL,
895                 old_oid ? old_oid->hash : NULL, flags, onerr);
896 }
897
898 int update_ref(const char *msg, const char *refname,
899                const unsigned char *new_sha1, const unsigned char *old_sha1,
900                unsigned int flags, enum action_on_err onerr)
901 {
902         struct ref_transaction *t = NULL;
903         struct strbuf err = STRBUF_INIT;
904         int ret = 0;
905
906         if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
907                 ret = write_pseudoref(refname, new_sha1, old_sha1, &err);
908         } else {
909                 t = ref_transaction_begin(&err);
910                 if (!t ||
911                     ref_transaction_update(t, refname, new_sha1, old_sha1,
912                                            flags, msg, &err) ||
913                     ref_transaction_commit(t, &err)) {
914                         ret = 1;
915                         ref_transaction_free(t);
916                 }
917         }
918         if (ret) {
919                 const char *str = "update_ref failed for ref '%s': %s";
920
921                 switch (onerr) {
922                 case UPDATE_REFS_MSG_ON_ERR:
923                         error(str, refname, err.buf);
924                         break;
925                 case UPDATE_REFS_DIE_ON_ERR:
926                         die(str, refname, err.buf);
927                         break;
928                 case UPDATE_REFS_QUIET_ON_ERR:
929                         break;
930                 }
931                 strbuf_release(&err);
932                 return 1;
933         }
934         strbuf_release(&err);
935         if (t)
936                 ref_transaction_free(t);
937         return 0;
938 }
939
940 char *shorten_unambiguous_ref(const char *refname, int strict)
941 {
942         int i;
943         static char **scanf_fmts;
944         static int nr_rules;
945         char *short_name;
946
947         if (!nr_rules) {
948                 /*
949                  * Pre-generate scanf formats from ref_rev_parse_rules[].
950                  * Generate a format suitable for scanf from a
951                  * ref_rev_parse_rules rule by interpolating "%s" at the
952                  * location of the "%.*s".
953                  */
954                 size_t total_len = 0;
955                 size_t offset = 0;
956
957                 /* the rule list is NULL terminated, count them first */
958                 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
959                         /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
960                         total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
961
962                 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
963
964                 offset = 0;
965                 for (i = 0; i < nr_rules; i++) {
966                         assert(offset < total_len);
967                         scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
968                         offset += snprintf(scanf_fmts[i], total_len - offset,
969                                            ref_rev_parse_rules[i], 2, "%s") + 1;
970                 }
971         }
972
973         /* bail out if there are no rules */
974         if (!nr_rules)
975                 return xstrdup(refname);
976
977         /* buffer for scanf result, at most refname must fit */
978         short_name = xstrdup(refname);
979
980         /* skip first rule, it will always match */
981         for (i = nr_rules - 1; i > 0 ; --i) {
982                 int j;
983                 int rules_to_fail = i;
984                 int short_name_len;
985
986                 if (1 != sscanf(refname, scanf_fmts[i], short_name))
987                         continue;
988
989                 short_name_len = strlen(short_name);
990
991                 /*
992                  * in strict mode, all (except the matched one) rules
993                  * must fail to resolve to a valid non-ambiguous ref
994                  */
995                 if (strict)
996                         rules_to_fail = nr_rules;
997
998                 /*
999                  * check if the short name resolves to a valid ref,
1000                  * but use only rules prior to the matched one
1001                  */
1002                 for (j = 0; j < rules_to_fail; j++) {
1003                         const char *rule = ref_rev_parse_rules[j];
1004                         char refname[PATH_MAX];
1005
1006                         /* skip matched rule */
1007                         if (i == j)
1008                                 continue;
1009
1010                         /*
1011                          * the short name is ambiguous, if it resolves
1012                          * (with this previous rule) to a valid ref
1013                          * read_ref() returns 0 on success
1014                          */
1015                         mksnpath(refname, sizeof(refname),
1016                                  rule, short_name_len, short_name);
1017                         if (ref_exists(refname))
1018                                 break;
1019                 }
1020
1021                 /*
1022                  * short name is non-ambiguous if all previous rules
1023                  * haven't resolved to a valid ref
1024                  */
1025                 if (j == rules_to_fail)
1026                         return short_name;
1027         }
1028
1029         free(short_name);
1030         return xstrdup(refname);
1031 }
1032
1033 static struct string_list *hide_refs;
1034
1035 int parse_hide_refs_config(const char *var, const char *value, const char *section)
1036 {
1037         if (!strcmp("transfer.hiderefs", var) ||
1038             /* NEEDSWORK: use parse_config_key() once both are merged */
1039             (starts_with(var, section) && var[strlen(section)] == '.' &&
1040              !strcmp(var + strlen(section), ".hiderefs"))) {
1041                 char *ref;
1042                 int len;
1043
1044                 if (!value)
1045                         return config_error_nonbool(var);
1046                 ref = xstrdup(value);
1047                 len = strlen(ref);
1048                 while (len && ref[len - 1] == '/')
1049                         ref[--len] = '\0';
1050                 if (!hide_refs) {
1051                         hide_refs = xcalloc(1, sizeof(*hide_refs));
1052                         hide_refs->strdup_strings = 1;
1053                 }
1054                 string_list_append(hide_refs, ref);
1055         }
1056         return 0;
1057 }
1058
1059 int ref_is_hidden(const char *refname, const char *refname_full)
1060 {
1061         int i;
1062
1063         if (!hide_refs)
1064                 return 0;
1065         for (i = hide_refs->nr - 1; i >= 0; i--) {
1066                 const char *match = hide_refs->items[i].string;
1067                 const char *subject;
1068                 int neg = 0;
1069                 int len;
1070
1071                 if (*match == '!') {
1072                         neg = 1;
1073                         match++;
1074                 }
1075
1076                 if (*match == '^') {
1077                         subject = refname_full;
1078                         match++;
1079                 } else {
1080                         subject = refname;
1081                 }
1082
1083                 /* refname can be NULL when namespaces are used. */
1084                 if (!subject || !starts_with(subject, match))
1085                         continue;
1086                 len = strlen(match);
1087                 if (!subject[len] || subject[len] == '/')
1088                         return !neg;
1089         }
1090         return 0;
1091 }
1092
1093 const char *find_descendant_ref(const char *dirname,
1094                                 const struct string_list *extras,
1095                                 const struct string_list *skip)
1096 {
1097         int pos;
1098
1099         if (!extras)
1100                 return NULL;
1101
1102         /*
1103          * Look at the place where dirname would be inserted into
1104          * extras. If there is an entry at that position that starts
1105          * with dirname (remember, dirname includes the trailing
1106          * slash) and is not in skip, then we have a conflict.
1107          */
1108         for (pos = string_list_find_insert_index(extras, dirname, 0);
1109              pos < extras->nr; pos++) {
1110                 const char *extra_refname = extras->items[pos].string;
1111
1112                 if (!starts_with(extra_refname, dirname))
1113                         break;
1114
1115                 if (!skip || !string_list_has_string(skip, extra_refname))
1116                         return extra_refname;
1117         }
1118         return NULL;
1119 }
1120
1121 int rename_ref_available(const char *old_refname, const char *new_refname)
1122 {
1123         struct string_list skip = STRING_LIST_INIT_NODUP;
1124         struct strbuf err = STRBUF_INIT;
1125         int ok;
1126
1127         string_list_insert(&skip, old_refname);
1128         ok = !verify_refname_available(new_refname, NULL, &skip, &err);
1129         if (!ok)
1130                 error("%s", err.buf);
1131
1132         string_list_clear(&skip, 0);
1133         strbuf_release(&err);
1134         return ok;
1135 }
1136
1137 int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1138 {
1139         struct object_id oid;
1140         int flag;
1141
1142         if (submodule) {
1143                 if (resolve_gitlink_ref(submodule, "HEAD", oid.hash) == 0)
1144                         return fn("HEAD", &oid, 0, cb_data);
1145
1146                 return 0;
1147         }
1148
1149         if (!read_ref_full("HEAD", RESOLVE_REF_READING, oid.hash, &flag))
1150                 return fn("HEAD", &oid, flag, cb_data);
1151
1152         return 0;
1153 }
1154
1155 int head_ref(each_ref_fn fn, void *cb_data)
1156 {
1157         return head_ref_submodule(NULL, fn, cb_data);
1158 }
1159
1160 /*
1161  * Call fn for each reference in the specified submodule for which the
1162  * refname begins with prefix. If trim is non-zero, then trim that
1163  * many characters off the beginning of each refname before passing
1164  * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1165  * include broken references in the iteration. If fn ever returns a
1166  * non-zero value, stop the iteration and return that value;
1167  * otherwise, return 0.
1168  */
1169 static int do_for_each_ref(const char *submodule, const char *prefix,
1170                            each_ref_fn fn, int trim, int flags, void *cb_data)
1171 {
1172         struct ref_store *refs = get_ref_store(submodule);
1173         struct ref_iterator *iter;
1174
1175         if (!refs)
1176                 return 0;
1177
1178         iter = refs->be->iterator_begin(refs, prefix, flags);
1179         iter = prefix_ref_iterator_begin(iter, prefix, trim);
1180
1181         return do_for_each_ref_iterator(iter, fn, cb_data);
1182 }
1183
1184 int for_each_ref(each_ref_fn fn, void *cb_data)
1185 {
1186         return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
1187 }
1188
1189 int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
1190 {
1191         return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
1192 }
1193
1194 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1195 {
1196         return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
1197 }
1198
1199 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1200 {
1201         unsigned int flag = 0;
1202
1203         if (broken)
1204                 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1205         return do_for_each_ref(NULL, prefix, fn, 0, flag, cb_data);
1206 }
1207
1208 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
1209                 each_ref_fn fn, void *cb_data)
1210 {
1211         return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
1212 }
1213
1214 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
1215 {
1216         return do_for_each_ref(NULL, git_replace_ref_base, fn,
1217                                strlen(git_replace_ref_base), 0, cb_data);
1218 }
1219
1220 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1221 {
1222         struct strbuf buf = STRBUF_INIT;
1223         int ret;
1224         strbuf_addf(&buf, "%srefs/", get_git_namespace());
1225         ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
1226         strbuf_release(&buf);
1227         return ret;
1228 }
1229
1230 int for_each_rawref(each_ref_fn fn, void *cb_data)
1231 {
1232         return do_for_each_ref(NULL, "", fn, 0,
1233                                DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1234 }
1235
1236 /* This function needs to return a meaningful errno on failure */
1237 static const char *resolve_ref_recursively(struct ref_store *refs,
1238                                            const char *refname,
1239                                            int resolve_flags,
1240                                            unsigned char *sha1, int *flags)
1241 {
1242         static struct strbuf sb_refname = STRBUF_INIT;
1243         int unused_flags;
1244         int symref_count;
1245
1246         if (!flags)
1247                 flags = &unused_flags;
1248
1249         *flags = 0;
1250
1251         if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1252                 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1253                     !refname_is_safe(refname)) {
1254                         errno = EINVAL;
1255                         return NULL;
1256                 }
1257
1258                 /*
1259                  * dwim_ref() uses REF_ISBROKEN to distinguish between
1260                  * missing refs and refs that were present but invalid,
1261                  * to complain about the latter to stderr.
1262                  *
1263                  * We don't know whether the ref exists, so don't set
1264                  * REF_ISBROKEN yet.
1265                  */
1266                 *flags |= REF_BAD_NAME;
1267         }
1268
1269         for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1270                 unsigned int read_flags = 0;
1271
1272                 if (refs->be->read_raw_ref(refs, refname,
1273                                            sha1, &sb_refname, &read_flags)) {
1274                         *flags |= read_flags;
1275                         if (errno != ENOENT || (resolve_flags & RESOLVE_REF_READING))
1276                                 return NULL;
1277                         hashclr(sha1);
1278                         if (*flags & REF_BAD_NAME)
1279                                 *flags |= REF_ISBROKEN;
1280                         return refname;
1281                 }
1282
1283                 *flags |= read_flags;
1284
1285                 if (!(read_flags & REF_ISSYMREF)) {
1286                         if (*flags & REF_BAD_NAME) {
1287                                 hashclr(sha1);
1288                                 *flags |= REF_ISBROKEN;
1289                         }
1290                         return refname;
1291                 }
1292
1293                 refname = sb_refname.buf;
1294                 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1295                         hashclr(sha1);
1296                         return refname;
1297                 }
1298                 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1299                         if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1300                             !refname_is_safe(refname)) {
1301                                 errno = EINVAL;
1302                                 return NULL;
1303                         }
1304
1305                         *flags |= REF_ISBROKEN | REF_BAD_NAME;
1306                 }
1307         }
1308
1309         errno = ELOOP;
1310         return NULL;
1311 }
1312
1313 /* backend functions */
1314 int refs_init_db(struct strbuf *err)
1315 {
1316         struct ref_store *refs = get_ref_store(NULL);
1317
1318         return refs->be->init_db(refs, err);
1319 }
1320
1321 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1322                                unsigned char *sha1, int *flags)
1323 {
1324         return resolve_ref_recursively(get_ref_store(NULL), refname,
1325                                        resolve_flags, sha1, flags);
1326 }
1327
1328 int resolve_gitlink_ref(const char *submodule, const char *refname,
1329                         unsigned char *sha1)
1330 {
1331         size_t len = strlen(submodule);
1332         struct ref_store *refs;
1333         int flags;
1334
1335         while (len && submodule[len - 1] == '/')
1336                 len--;
1337
1338         if (!len)
1339                 return -1;
1340
1341         if (submodule[len]) {
1342                 /* We need to strip off one or more trailing slashes */
1343                 char *stripped = xmemdupz(submodule, len);
1344
1345                 refs = get_ref_store(stripped);
1346                 free(stripped);
1347         } else {
1348                 refs = get_ref_store(submodule);
1349         }
1350
1351         if (!refs)
1352                 return -1;
1353
1354         if (!resolve_ref_recursively(refs, refname, 0, sha1, &flags) ||
1355             is_null_sha1(sha1))
1356                 return -1;
1357         return 0;
1358 }
1359
1360 /* A pointer to the ref_store for the main repository: */
1361 static struct ref_store *main_ref_store;
1362
1363 /* A linked list of ref_stores for submodules: */
1364 static struct ref_store *submodule_ref_stores;
1365
1366 void base_ref_store_init(struct ref_store *refs,
1367                          const struct ref_storage_be *be,
1368                          const char *submodule)
1369 {
1370         refs->be = be;
1371         if (!submodule) {
1372                 if (main_ref_store)
1373                         die("BUG: main_ref_store initialized twice");
1374
1375                 refs->submodule = "";
1376                 refs->next = NULL;
1377                 main_ref_store = refs;
1378         } else {
1379                 if (lookup_ref_store(submodule))
1380                         die("BUG: ref_store for submodule '%s' initialized twice",
1381                             submodule);
1382
1383                 refs->submodule = xstrdup(submodule);
1384                 refs->next = submodule_ref_stores;
1385                 submodule_ref_stores = refs;
1386         }
1387 }
1388
1389 struct ref_store *ref_store_init(const char *submodule)
1390 {
1391         const char *be_name = "files";
1392         struct ref_storage_be *be = find_ref_storage_backend(be_name);
1393
1394         if (!be)
1395                 die("BUG: reference backend %s is unknown", be_name);
1396
1397         if (!submodule || !*submodule)
1398                 return be->init(NULL);
1399         else
1400                 return be->init(submodule);
1401 }
1402
1403 struct ref_store *lookup_ref_store(const char *submodule)
1404 {
1405         struct ref_store *refs;
1406
1407         if (!submodule || !*submodule)
1408                 return main_ref_store;
1409
1410         for (refs = submodule_ref_stores; refs; refs = refs->next) {
1411                 if (!strcmp(submodule, refs->submodule))
1412                         return refs;
1413         }
1414
1415         return NULL;
1416 }
1417
1418 struct ref_store *get_ref_store(const char *submodule)
1419 {
1420         struct ref_store *refs;
1421
1422         if (!submodule || !*submodule) {
1423                 refs = lookup_ref_store(NULL);
1424
1425                 if (!refs)
1426                         refs = ref_store_init(NULL);
1427         } else {
1428                 refs = lookup_ref_store(submodule);
1429
1430                 if (!refs) {
1431                         struct strbuf submodule_sb = STRBUF_INIT;
1432
1433                         strbuf_addstr(&submodule_sb, submodule);
1434                         if (is_nonbare_repository_dir(&submodule_sb))
1435                                 refs = ref_store_init(submodule);
1436                         strbuf_release(&submodule_sb);
1437                 }
1438         }
1439
1440         return refs;
1441 }
1442
1443 void assert_main_repository(struct ref_store *refs, const char *caller)
1444 {
1445         if (*refs->submodule)
1446                 die("BUG: %s called for a submodule", caller);
1447 }
1448
1449 /* backend functions */
1450 int pack_refs(unsigned int flags)
1451 {
1452         struct ref_store *refs = get_ref_store(NULL);
1453
1454         return refs->be->pack_refs(refs, flags);
1455 }
1456
1457 int peel_ref(const char *refname, unsigned char *sha1)
1458 {
1459         struct ref_store *refs = get_ref_store(NULL);
1460
1461         return refs->be->peel_ref(refs, refname, sha1);
1462 }
1463
1464 int create_symref(const char *ref_target, const char *refs_heads_master,
1465                   const char *logmsg)
1466 {
1467         struct ref_store *refs = get_ref_store(NULL);
1468
1469         return refs->be->create_symref(refs, ref_target, refs_heads_master,
1470                                        logmsg);
1471 }
1472
1473 int ref_transaction_commit(struct ref_transaction *transaction,
1474                            struct strbuf *err)
1475 {
1476         struct ref_store *refs = get_ref_store(NULL);
1477
1478         return refs->be->transaction_commit(refs, transaction, err);
1479 }
1480
1481 int verify_refname_available(const char *refname,
1482                              const struct string_list *extra,
1483                              const struct string_list *skip,
1484                              struct strbuf *err)
1485 {
1486         struct ref_store *refs = get_ref_store(NULL);
1487
1488         return refs->be->verify_refname_available(refs, refname, extra, skip, err);
1489 }
1490
1491 int for_each_reflog(each_ref_fn fn, void *cb_data)
1492 {
1493         struct ref_store *refs = get_ref_store(NULL);
1494         struct ref_iterator *iter;
1495
1496         iter = refs->be->reflog_iterator_begin(refs);
1497
1498         return do_for_each_ref_iterator(iter, fn, cb_data);
1499 }
1500
1501 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
1502                                 void *cb_data)
1503 {
1504         struct ref_store *refs = get_ref_store(NULL);
1505
1506         return refs->be->for_each_reflog_ent_reverse(refs, refname,
1507                                                      fn, cb_data);
1508 }
1509
1510 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
1511                         void *cb_data)
1512 {
1513         struct ref_store *refs = get_ref_store(NULL);
1514
1515         return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
1516 }
1517
1518 int reflog_exists(const char *refname)
1519 {
1520         struct ref_store *refs = get_ref_store(NULL);
1521
1522         return refs->be->reflog_exists(refs, refname);
1523 }
1524
1525 int safe_create_reflog(const char *refname, int force_create,
1526                        struct strbuf *err)
1527 {
1528         struct ref_store *refs = get_ref_store(NULL);
1529
1530         return refs->be->create_reflog(refs, refname, force_create, err);
1531 }
1532
1533 int delete_reflog(const char *refname)
1534 {
1535         struct ref_store *refs = get_ref_store(NULL);
1536
1537         return refs->be->delete_reflog(refs, refname);
1538 }
1539
1540 int reflog_expire(const char *refname, const unsigned char *sha1,
1541                   unsigned int flags,
1542                   reflog_expiry_prepare_fn prepare_fn,
1543                   reflog_expiry_should_prune_fn should_prune_fn,
1544                   reflog_expiry_cleanup_fn cleanup_fn,
1545                   void *policy_cb_data)
1546 {
1547         struct ref_store *refs = get_ref_store(NULL);
1548
1549         return refs->be->reflog_expire(refs, refname, sha1, flags,
1550                                        prepare_fn, should_prune_fn,
1551                                        cleanup_fn, policy_cb_data);
1552 }
1553
1554 int initial_ref_transaction_commit(struct ref_transaction *transaction,
1555                                    struct strbuf *err)
1556 {
1557         struct ref_store *refs = get_ref_store(NULL);
1558
1559         return refs->be->initial_transaction_commit(refs, transaction, err);
1560 }
1561
1562 int delete_refs(struct string_list *refnames, unsigned int flags)
1563 {
1564         struct ref_store *refs = get_ref_store(NULL);
1565
1566         return refs->be->delete_refs(refs, refnames, flags);
1567 }
1568
1569 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1570 {
1571         struct ref_store *refs = get_ref_store(NULL);
1572
1573         return refs->be->rename_ref(refs, oldref, newref, logmsg);
1574 }