git.oblomov.eu Git - git/blob - refs.c

   1 /*
   2  * The backend-independent part of the reference module.
   3  */
   4
   5 #include "cache.h"
   6 #include "config.h"
   7 #include "hashmap.h"
   8 #include "lockfile.h"
   9 #include "iterator.h"
  10 #include "refs.h"
  11 #include "refs/refs-internal.h"
  12 #include "object-store.h"
  13 #include "object.h"
  14 #include "tag.h"
  15 #include "submodule.h"
  16 #include "worktree.h"
  17 #include "argv-array.h"
  18 #include "repository.h"
  19
  20 /*
  21  * List of all available backends
  22  */
  23 static struct ref_storage_be *refs_backends = &refs_be_files;
  24
  25 static struct ref_storage_be *find_ref_storage_backend(const char *name)
  26 {
  27         struct ref_storage_be *be;
  28         for (be = refs_backends; be; be = be->next)
  29                 if (!strcmp(be->name, name))
  30                         return be;
  31         return NULL;
  32 }
  33
  34 int ref_storage_backend_exists(const char *name)
  35 {
  36         return find_ref_storage_backend(name) != NULL;
  37 }
  38
  39 /*
  40  * How to handle various characters in refnames:
  41  * 0: An acceptable character for refs
  42  * 1: End-of-component
  43  * 2: ., look for a preceding . to reject .. in refs
  44  * 3: {, look for a preceding @ to reject @{ in refs
  45  * 4: A bad character: ASCII control characters, and
  46  *    ":", "?", "[", "\", "^", "~", SP, or TAB
  47  * 5: *, reject unless REFNAME_REFSPEC_PATTERN is set
  48  */
  49 static unsigned char refname_disposition[256] = {
  50         1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
  51         4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
  52         4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 2, 1,
  53         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4,
  54         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  55         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 4, 0,
  56         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  57         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 4
  58 };
  59
  60 /*
  61  * Try to read one refname component from the front of refname.
  62  * Return the length of the component found, or -1 if the component is
  63  * not legal.  It is legal if it is something reasonable to have under
  64  * ".git/refs/"; We do not like it if:
  65  *
  66  * - any path component of it begins with ".", or
  67  * - it has double dots "..", or
  68  * - it has ASCII control characters, or
  69  * - it has ":", "?", "[", "\", "^", "~", SP, or TAB anywhere, or
  70  * - it has "*" anywhere unless REFNAME_REFSPEC_PATTERN is set, or
  71  * - it ends with a "/", or
  72  * - it ends with ".lock", or
  73  * - it contains a "@{" portion
  74  */
  75 static int check_refname_component(const char *refname, int *flags)
  76 {
  77         const char *cp;
  78         char last = '\0';
  79
  80         for (cp = refname; ; cp++) {
  81                 int ch = *cp & 255;
  82                 unsigned char disp = refname_disposition[ch];
  83                 switch (disp) {
  84                 case 1:
  85                         goto out;
  86                 case 2:
  87                         if (last == '.')
  88                                 return -1; /* Refname contains "..". */
  89                         break;
  90                 case 3:
  91                         if (last == '@')
  92                                 return -1; /* Refname contains "@{". */
  93                         break;
  94                 case 4:
  95                         return -1;
  96                 case 5:
  97                         if (!(*flags & REFNAME_REFSPEC_PATTERN))
  98                                 return -1; /* refspec can't be a pattern */
  99
 100                         /*
 101                          * Unset the pattern flag so that we only accept
 102                          * a single asterisk for one side of refspec.
 103                          */
 104                         *flags &= ~ REFNAME_REFSPEC_PATTERN;
 105                         break;
 106                 }
 107                 last = ch;
 108         }
 109 out:
 110         if (cp == refname)
 111                 return 0; /* Component has zero length. */
 112         if (refname[0] == '.')
 113                 return -1; /* Component starts with '.'. */
 114         if (cp - refname >= LOCK_SUFFIX_LEN &&
 115             !memcmp(cp - LOCK_SUFFIX_LEN, LOCK_SUFFIX, LOCK_SUFFIX_LEN))
 116                 return -1; /* Refname ends with ".lock". */
 117         return cp - refname;
 118 }
 119
 120 int check_refname_format(const char *refname, int flags)
 121 {
 122         int component_len, component_count = 0;
 123
 124         if (!strcmp(refname, "@"))
 125                 /* Refname is a single character '@'. */
 126                 return -1;
 127
 128         while (1) {
 129                 /* We are at the start of a path component. */
 130                 component_len = check_refname_component(refname, &flags);
 131                 if (component_len <= 0)
 132                         return -1;
 133
 134                 component_count++;
 135                 if (refname[component_len] == '\0')
 136                         break;
 137                 /* Skip to next component. */
 138                 refname += component_len + 1;
 139         }
 140
 141         if (refname[component_len - 1] == '.')
 142                 return -1; /* Refname ends with '.'. */
 143         if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
 144                 return -1; /* Refname has only one component. */
 145         return 0;
 146 }
 147
 148 int refname_is_safe(const char *refname)
 149 {
 150         const char *rest;
 151
 152         if (skip_prefix(refname, "refs/", &rest)) {
 153                 char *buf;
 154                 int result;
 155                 size_t restlen = strlen(rest);
 156
 157                 /* rest must not be empty, or start or end with "/" */
 158                 if (!restlen || *rest == '/' || rest[restlen - 1] == '/')
 159                         return 0;
 160
 161                 /*
 162                  * Does the refname try to escape refs/?
 163                  * For example: refs/foo/../bar is safe but refs/foo/../../bar
 164                  * is not.
 165                  */
 166                 buf = xmallocz(restlen);
 167                 result = !normalize_path_copy(buf, rest) && !strcmp(buf, rest);
 168                 free(buf);
 169                 return result;
 170         }
 171
 172         do {
 173                 if (!isupper(*refname) && *refname != '_')
 174                         return 0;
 175                 refname++;
 176         } while (*refname);
 177         return 1;
 178 }
 179
 180 /*
 181  * Return true if refname, which has the specified oid and flags, can
 182  * be resolved to an object in the database. If the referred-to object
 183  * does not exist, emit a warning and return false.
 184  */
 185 int ref_resolves_to_object(const char *refname,
 186                            const struct object_id *oid,
 187                            unsigned int flags)
 188 {
 189         if (flags & REF_ISBROKEN)
 190                 return 0;
 191         if (!has_sha1_file(oid->hash)) {
 192                 error(_("%s does not point to a valid object!"), refname);
 193                 return 0;
 194         }
 195         return 1;
 196 }
 197
 198 char *refs_resolve_refdup(struct ref_store *refs,
 199                           const char *refname, int resolve_flags,
 200                           struct object_id *oid, int *flags)
 201 {
 202         const char *result;
 203
 204         result = refs_resolve_ref_unsafe(refs, refname, resolve_flags,
 205                                          oid, flags);
 206         return xstrdup_or_null(result);
 207 }
 208
 209 char *resolve_refdup(const char *refname, int resolve_flags,
 210                      struct object_id *oid, int *flags)
 211 {
 212         return refs_resolve_refdup(get_main_ref_store(the_repository),
 213                                    refname, resolve_flags,
 214                                    oid, flags);
 215 }
 216
 217 /* The argument to filter_refs */
 218 struct ref_filter {
 219         const char *pattern;
 220         each_ref_fn *fn;
 221         void *cb_data;
 222 };
 223
 224 int refs_read_ref_full(struct ref_store *refs, const char *refname,
 225                        int resolve_flags, struct object_id *oid, int *flags)
 226 {
 227         if (refs_resolve_ref_unsafe(refs, refname, resolve_flags, oid, flags))
 228                 return 0;
 229         return -1;
 230 }
 231
 232 int read_ref_full(const char *refname, int resolve_flags, struct object_id *oid, int *flags)
 233 {
 234         return refs_read_ref_full(get_main_ref_store(the_repository), refname,
 235                                   resolve_flags, oid, flags);
 236 }
 237
 238 int read_ref(const char *refname, struct object_id *oid)
 239 {
 240         return read_ref_full(refname, RESOLVE_REF_READING, oid, NULL);
 241 }
 242
 243 int ref_exists(const char *refname)
 244 {
 245         return !!resolve_ref_unsafe(refname, RESOLVE_REF_READING, NULL, NULL);
 246 }
 247
 248 static int match_ref_pattern(const char *refname,
 249                              const struct string_list_item *item)
 250 {
 251         int matched = 0;
 252         if (item->util == NULL) {
 253                 if (!wildmatch(item->string, refname, 0))
 254                         matched = 1;
 255         } else {
 256                 const char *rest;
 257                 if (skip_prefix(refname, item->string, &rest) &&
 258                     (!*rest || *rest == '/'))
 259                         matched = 1;
 260         }
 261         return matched;
 262 }
 263
 264 int ref_filter_match(const char *refname,
 265                      const struct string_list *include_patterns,
 266                      const struct string_list *exclude_patterns)
 267 {
 268         struct string_list_item *item;
 269
 270         if (exclude_patterns && exclude_patterns->nr) {
 271                 for_each_string_list_item(item, exclude_patterns) {
 272                         if (match_ref_pattern(refname, item))
 273                                 return 0;
 274                 }
 275         }
 276
 277         if (include_patterns && include_patterns->nr) {
 278                 int found = 0;
 279                 for_each_string_list_item(item, include_patterns) {
 280                         if (match_ref_pattern(refname, item)) {
 281                                 found = 1;
 282                                 break;
 283                         }
 284                 }
 285
 286                 if (!found)
 287                         return 0;
 288         }
 289         return 1;
 290 }
 291
 292 static int filter_refs(const char *refname, const struct object_id *oid,
 293                            int flags, void *data)
 294 {
 295         struct ref_filter *filter = (struct ref_filter *)data;
 296
 297         if (wildmatch(filter->pattern, refname, 0))
 298                 return 0;
 299         return filter->fn(refname, oid, flags, filter->cb_data);
 300 }
 301
 302 enum peel_status peel_object(const struct object_id *name, struct object_id *oid)
 303 {
 304         struct object *o = lookup_unknown_object(name->hash);
 305
 306         if (o->type == OBJ_NONE) {
 307                 int type = oid_object_info(the_repository, name, NULL);
 308                 if (type < 0 || !object_as_type(the_repository, o, type, 0))
 309                         return PEEL_INVALID;
 310         }
 311
 312         if (o->type != OBJ_TAG)
 313                 return PEEL_NON_TAG;
 314
 315         o = deref_tag_noverify(o);
 316         if (!o)
 317                 return PEEL_INVALID;
 318
 319         oidcpy(oid, &o->oid);
 320         return PEEL_PEELED;
 321 }
 322
 323 struct warn_if_dangling_data {
 324         FILE *fp;
 325         const char *refname;
 326         const struct string_list *refnames;
 327         const char *msg_fmt;
 328 };
 329
 330 static int warn_if_dangling_symref(const char *refname, const struct object_id *oid,
 331                                    int flags, void *cb_data)
 332 {
 333         struct warn_if_dangling_data *d = cb_data;
 334         const char *resolves_to;
 335
 336         if (!(flags & REF_ISSYMREF))
 337                 return 0;
 338
 339         resolves_to = resolve_ref_unsafe(refname, 0, NULL, NULL);
 340         if (!resolves_to
 341             || (d->refname
 342                 ? strcmp(resolves_to, d->refname)
 343                 : !string_list_has_string(d->refnames, resolves_to))) {
 344                 return 0;
 345         }
 346
 347         fprintf(d->fp, d->msg_fmt, refname);
 348         fputc('\n', d->fp);
 349         return 0;
 350 }
 351
 352 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
 353 {
 354         struct warn_if_dangling_data data;
 355
 356         data.fp = fp;
 357         data.refname = refname;
 358         data.refnames = NULL;
 359         data.msg_fmt = msg_fmt;
 360         for_each_rawref(warn_if_dangling_symref, &data);
 361 }
 362
 363 void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames)
 364 {
 365         struct warn_if_dangling_data data;
 366
 367         data.fp = fp;
 368         data.refname = NULL;
 369         data.refnames = refnames;
 370         data.msg_fmt = msg_fmt;
 371         for_each_rawref(warn_if_dangling_symref, &data);
 372 }
 373
 374 int refs_for_each_tag_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
 375 {
 376         return refs_for_each_ref_in(refs, "refs/tags/", fn, cb_data);
 377 }
 378
 379 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
 380 {
 381         return refs_for_each_tag_ref(get_main_ref_store(the_repository), fn, cb_data);
 382 }
 383
 384 int refs_for_each_branch_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
 385 {
 386         return refs_for_each_ref_in(refs, "refs/heads/", fn, cb_data);
 387 }
 388
 389 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
 390 {
 391         return refs_for_each_branch_ref(get_main_ref_store(the_repository), fn, cb_data);
 392 }
 393
 394 int refs_for_each_remote_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
 395 {
 396         return refs_for_each_ref_in(refs, "refs/remotes/", fn, cb_data);
 397 }
 398
 399 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
 400 {
 401         return refs_for_each_remote_ref(get_main_ref_store(the_repository), fn, cb_data);
 402 }
 403
 404 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
 405 {
 406         struct strbuf buf = STRBUF_INIT;
 407         int ret = 0;
 408         struct object_id oid;
 409         int flag;
 410
 411         strbuf_addf(&buf, "%sHEAD", get_git_namespace());
 412         if (!read_ref_full(buf.buf, RESOLVE_REF_READING, &oid, &flag))
 413                 ret = fn(buf.buf, &oid, flag, cb_data);
 414         strbuf_release(&buf);
 415
 416         return ret;
 417 }
 418
 419 void normalize_glob_ref(struct string_list_item *item, const char *prefix,
 420                         const char *pattern)
 421 {
 422         struct strbuf normalized_pattern = STRBUF_INIT;
 423
 424         if (*pattern == '/')
 425                 BUG("pattern must not start with '/'");
 426
 427         if (prefix) {
 428                 strbuf_addstr(&normalized_pattern, prefix);
 429         }
 430         else if (!starts_with(pattern, "refs/"))
 431                 strbuf_addstr(&normalized_pattern, "refs/");
 432         strbuf_addstr(&normalized_pattern, pattern);
 433         strbuf_strip_suffix(&normalized_pattern, "/");
 434
 435         item->string = strbuf_detach(&normalized_pattern, NULL);
 436         item->util = has_glob_specials(pattern) ? NULL : item->string;
 437         strbuf_release(&normalized_pattern);
 438 }
 439
 440 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
 441         const char *prefix, void *cb_data)
 442 {
 443         struct strbuf real_pattern = STRBUF_INIT;
 444         struct ref_filter filter;
 445         int ret;
 446
 447         if (!prefix && !starts_with(pattern, "refs/"))
 448                 strbuf_addstr(&real_pattern, "refs/");
 449         else if (prefix)
 450                 strbuf_addstr(&real_pattern, prefix);
 451         strbuf_addstr(&real_pattern, pattern);
 452
 453         if (!has_glob_specials(pattern)) {
 454                 /* Append implied '/' '*' if not present. */
 455                 strbuf_complete(&real_pattern, '/');
 456                 /* No need to check for '*', there is none. */
 457                 strbuf_addch(&real_pattern, '*');
 458         }
 459
 460         filter.pattern = real_pattern.buf;
 461         filter.fn = fn;
 462         filter.cb_data = cb_data;
 463         ret = for_each_ref(filter_refs, &filter);
 464
 465         strbuf_release(&real_pattern);
 466         return ret;
 467 }
 468
 469 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
 470 {
 471         return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
 472 }
 473
 474 const char *prettify_refname(const char *name)
 475 {
 476         if (skip_prefix(name, "refs/heads/", &name) ||
 477             skip_prefix(name, "refs/tags/", &name) ||
 478             skip_prefix(name, "refs/remotes/", &name))
 479                 ; /* nothing */
 480         return name;
 481 }
 482
 483 static const char *ref_rev_parse_rules[] = {
 484         "%.*s",
 485         "refs/%.*s",
 486         "refs/tags/%.*s",
 487         "refs/heads/%.*s",
 488         "refs/remotes/%.*s",
 489         "refs/remotes/%.*s/HEAD",
 490         NULL
 491 };
 492
 493 #define NUM_REV_PARSE_RULES (ARRAY_SIZE(ref_rev_parse_rules) - 1)
 494
 495 /*
 496  * Is it possible that the caller meant full_name with abbrev_name?
 497  * If so return a non-zero value to signal "yes"; the magnitude of
 498  * the returned value gives the precedence used for disambiguation.
 499  *
 500  * If abbrev_name cannot mean full_name, return 0.
 501  */
 502 int refname_match(const char *abbrev_name, const char *full_name)
 503 {
 504         const char **p;
 505         const int abbrev_name_len = strlen(abbrev_name);
 506         const int num_rules = NUM_REV_PARSE_RULES;
 507
 508         for (p = ref_rev_parse_rules; *p; p++)
 509                 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name)))
 510                         return &ref_rev_parse_rules[num_rules] - p;
 511
 512         return 0;
 513 }
 514
 515 /*
 516  * Given a 'prefix' expand it by the rules in 'ref_rev_parse_rules' and add
 517  * the results to 'prefixes'
 518  */
 519 void expand_ref_prefix(struct argv_array *prefixes, const char *prefix)
 520 {
 521         const char **p;
 522         int len = strlen(prefix);
 523
 524         for (p = ref_rev_parse_rules; *p; p++)
 525                 argv_array_pushf(prefixes, *p, len, prefix);
 526 }
 527
 528 /*
 529  * *string and *len will only be substituted, and *string returned (for
 530  * later free()ing) if the string passed in is a magic short-hand form
 531  * to name a branch.
 532  */
 533 static char *substitute_branch_name(const char **string, int *len)
 534 {
 535         struct strbuf buf = STRBUF_INIT;
 536         int ret = interpret_branch_name(*string, *len, &buf, 0);
 537
 538         if (ret == *len) {
 539                 size_t size;
 540                 *string = strbuf_detach(&buf, &size);
 541                 *len = size;
 542                 return (char *)*string;
 543         }
 544
 545         return NULL;
 546 }
 547
 548 int dwim_ref(const char *str, int len, struct object_id *oid, char **ref)
 549 {
 550         char *last_branch = substitute_branch_name(&str, &len);
 551         int   refs_found  = expand_ref(str, len, oid, ref);
 552         free(last_branch);
 553         return refs_found;
 554 }
 555
 556 int expand_ref(const char *str, int len, struct object_id *oid, char **ref)
 557 {
 558         const char **p, *r;
 559         int refs_found = 0;
 560         struct strbuf fullref = STRBUF_INIT;
 561
 562         *ref = NULL;
 563         for (p = ref_rev_parse_rules; *p; p++) {
 564                 struct object_id oid_from_ref;
 565                 struct object_id *this_result;
 566                 int flag;
 567
 568                 this_result = refs_found ? &oid_from_ref : oid;
 569                 strbuf_reset(&fullref);
 570                 strbuf_addf(&fullref, *p, len, str);
 571                 r = resolve_ref_unsafe(fullref.buf, RESOLVE_REF_READING,
 572                                        this_result, &flag);
 573                 if (r) {
 574                         if (!refs_found++)
 575                                 *ref = xstrdup(r);
 576                         if (!warn_ambiguous_refs)
 577                                 break;
 578                 } else if ((flag & REF_ISSYMREF) && strcmp(fullref.buf, "HEAD")) {
 579                         warning(_("ignoring dangling symref %s"), fullref.buf);
 580                 } else if ((flag & REF_ISBROKEN) && strchr(fullref.buf, '/')) {
 581                         warning(_("ignoring broken ref %s"), fullref.buf);
 582                 }
 583         }
 584         strbuf_release(&fullref);
 585         return refs_found;
 586 }
 587
 588 int dwim_log(const char *str, int len, struct object_id *oid, char **log)
 589 {
 590         char *last_branch = substitute_branch_name(&str, &len);
 591         const char **p;
 592         int logs_found = 0;
 593         struct strbuf path = STRBUF_INIT;
 594
 595         *log = NULL;
 596         for (p = ref_rev_parse_rules; *p; p++) {
 597                 struct object_id hash;
 598                 const char *ref, *it;
 599
 600                 strbuf_reset(&path);
 601                 strbuf_addf(&path, *p, len, str);
 602                 ref = resolve_ref_unsafe(path.buf, RESOLVE_REF_READING,
 603                                          &hash, NULL);
 604                 if (!ref)
 605                         continue;
 606                 if (reflog_exists(path.buf))
 607                         it = path.buf;
 608                 else if (strcmp(ref, path.buf) && reflog_exists(ref))
 609                         it = ref;
 610                 else
 611                         continue;
 612                 if (!logs_found++) {
 613                         *log = xstrdup(it);
 614                         oidcpy(oid, &hash);
 615                 }
 616                 if (!warn_ambiguous_refs)
 617                         break;
 618         }
 619         strbuf_release(&path);
 620         free(last_branch);
 621         return logs_found;
 622 }
 623
 624 static int is_per_worktree_ref(const char *refname)
 625 {
 626         return !strcmp(refname, "HEAD") ||
 627                 starts_with(refname, "refs/bisect/") ||
 628                 starts_with(refname, "refs/rewritten/");
 629 }
 630
 631 static int is_pseudoref_syntax(const char *refname)
 632 {
 633         const char *c;
 634
 635         for (c = refname; *c; c++) {
 636                 if (!isupper(*c) && *c != '-' && *c != '_')
 637                         return 0;
 638         }
 639
 640         return 1;
 641 }
 642
 643 enum ref_type ref_type(const char *refname)
 644 {
 645         if (is_per_worktree_ref(refname))
 646                 return REF_TYPE_PER_WORKTREE;
 647         if (is_pseudoref_syntax(refname))
 648                 return REF_TYPE_PSEUDOREF;
 649        return REF_TYPE_NORMAL;
 650 }
 651
 652 long get_files_ref_lock_timeout_ms(void)
 653 {
 654         static int configured = 0;
 655
 656         /* The default timeout is 100 ms: */
 657         static int timeout_ms = 100;
 658
 659         if (!configured) {
 660                 git_config_get_int("core.filesreflocktimeout", &timeout_ms);
 661                 configured = 1;
 662         }
 663
 664         return timeout_ms;
 665 }
 666
 667 static int write_pseudoref(const char *pseudoref, const struct object_id *oid,
 668                            const struct object_id *old_oid, struct strbuf *err)
 669 {
 670         const char *filename;
 671         int fd;
 672         struct lock_file lock = LOCK_INIT;
 673         struct strbuf buf = STRBUF_INIT;
 674         int ret = -1;
 675
 676         if (!oid)
 677                 return 0;
 678
 679         strbuf_addf(&buf, "%s\n", oid_to_hex(oid));
 680
 681         filename = git_path("%s", pseudoref);
 682         fd = hold_lock_file_for_update_timeout(&lock, filename, 0,
 683                                                get_files_ref_lock_timeout_ms());
 684         if (fd < 0) {
 685                 strbuf_addf(err, _("could not open '%s' for writing: %s"),
 686                             filename, strerror(errno));
 687                 goto done;
 688         }
 689
 690         if (old_oid) {
 691                 struct object_id actual_old_oid;
 692
 693                 if (read_ref(pseudoref, &actual_old_oid)) {
 694                         if (!is_null_oid(old_oid)) {
 695                                 strbuf_addf(err, _("could not read ref '%s'"),
 696                                             pseudoref);
 697                                 rollback_lock_file(&lock);
 698                                 goto done;
 699                         }
 700                 } else if (is_null_oid(old_oid)) {
 701                         strbuf_addf(err, _("ref '%s' already exists"),
 702                                     pseudoref);
 703                         rollback_lock_file(&lock);
 704                         goto done;
 705                 } else if (oidcmp(&actual_old_oid, old_oid)) {
 706                         strbuf_addf(err, _("unexpected object ID when writing '%s'"),
 707                                     pseudoref);
 708                         rollback_lock_file(&lock);
 709                         goto done;
 710                 }
 711         }
 712
 713         if (write_in_full(fd, buf.buf, buf.len) < 0) {
 714                 strbuf_addf(err, _("could not write to '%s'"), filename);
 715                 rollback_lock_file(&lock);
 716                 goto done;
 717         }
 718
 719         commit_lock_file(&lock);
 720         ret = 0;
 721 done:
 722         strbuf_release(&buf);
 723         return ret;
 724 }
 725
 726 static int delete_pseudoref(const char *pseudoref, const struct object_id *old_oid)
 727 {
 728         const char *filename;
 729
 730         filename = git_path("%s", pseudoref);
 731
 732         if (old_oid && !is_null_oid(old_oid)) {
 733                 struct lock_file lock = LOCK_INIT;
 734                 int fd;
 735                 struct object_id actual_old_oid;
 736
 737                 fd = hold_lock_file_for_update_timeout(
 738                                 &lock, filename, 0,
 739                                 get_files_ref_lock_timeout_ms());
 740                 if (fd < 0) {
 741                         error_errno(_("could not open '%s' for writing"),
 742                                     filename);
 743                         return -1;
 744                 }
 745                 if (read_ref(pseudoref, &actual_old_oid))
 746                         die(_("could not read ref '%s'"), pseudoref);
 747                 if (oidcmp(&actual_old_oid, old_oid)) {
 748                         error(_("unexpected object ID when deleting '%s'"),
 749                               pseudoref);
 750                         rollback_lock_file(&lock);
 751                         return -1;
 752                 }
 753
 754                 unlink(filename);
 755                 rollback_lock_file(&lock);
 756         } else {
 757                 unlink(filename);
 758         }
 759
 760         return 0;
 761 }
 762
 763 int refs_delete_ref(struct ref_store *refs, const char *msg,
 764                     const char *refname,
 765                     const struct object_id *old_oid,
 766                     unsigned int flags)
 767 {
 768         struct ref_transaction *transaction;
 769         struct strbuf err = STRBUF_INIT;
 770
 771         if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
 772                 assert(refs == get_main_ref_store(the_repository));
 773                 return delete_pseudoref(refname, old_oid);
 774         }
 775
 776         transaction = ref_store_transaction_begin(refs, &err);
 777         if (!transaction ||
 778             ref_transaction_delete(transaction, refname, old_oid,
 779                                    flags, msg, &err) ||
 780             ref_transaction_commit(transaction, &err)) {
 781                 error("%s", err.buf);
 782                 ref_transaction_free(transaction);
 783                 strbuf_release(&err);
 784                 return 1;
 785         }
 786         ref_transaction_free(transaction);
 787         strbuf_release(&err);
 788         return 0;
 789 }
 790
 791 int delete_ref(const char *msg, const char *refname,
 792                const struct object_id *old_oid, unsigned int flags)
 793 {
 794         return refs_delete_ref(get_main_ref_store(the_repository), msg, refname,
 795                                old_oid, flags);
 796 }
 797
 798 void copy_reflog_msg(struct strbuf *sb, const char *msg)
 799 {
 800         char c;
 801         int wasspace = 1;
 802
 803         strbuf_addch(sb, '\t');
 804         while ((c = *msg++)) {
 805                 if (wasspace && isspace(c))
 806                         continue;
 807                 wasspace = isspace(c);
 808                 if (wasspace)
 809                         c = ' ';
 810                 strbuf_addch(sb, c);
 811         }
 812         strbuf_rtrim(sb);
 813 }
 814
 815 int should_autocreate_reflog(const char *refname)
 816 {
 817         switch (log_all_ref_updates) {
 818         case LOG_REFS_ALWAYS:
 819                 return 1;
 820         case LOG_REFS_NORMAL:
 821                 return starts_with(refname, "refs/heads/") ||
 822                         starts_with(refname, "refs/remotes/") ||
 823                         starts_with(refname, "refs/notes/") ||
 824                         !strcmp(refname, "HEAD");
 825         default:
 826                 return 0;
 827         }
 828 }
 829
 830 int is_branch(const char *refname)
 831 {
 832         return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
 833 }
 834
 835 struct read_ref_at_cb {
 836         const char *refname;
 837         timestamp_t at_time;
 838         int cnt;
 839         int reccnt;
 840         struct object_id *oid;
 841         int found_it;
 842
 843         struct object_id ooid;
 844         struct object_id noid;
 845         int tz;
 846         timestamp_t date;
 847         char **msg;
 848         timestamp_t *cutoff_time;
 849         int *cutoff_tz;
 850         int *cutoff_cnt;
 851 };
 852
 853 static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
 854                 const char *email, timestamp_t timestamp, int tz,
 855                 const char *message, void *cb_data)
 856 {
 857         struct read_ref_at_cb *cb = cb_data;
 858
 859         cb->reccnt++;
 860         cb->tz = tz;
 861         cb->date = timestamp;
 862
 863         if (timestamp <= cb->at_time || cb->cnt == 0) {
 864                 if (cb->msg)
 865                         *cb->msg = xstrdup(message);
 866                 if (cb->cutoff_time)
 867                         *cb->cutoff_time = timestamp;
 868                 if (cb->cutoff_tz)
 869                         *cb->cutoff_tz = tz;
 870                 if (cb->cutoff_cnt)
 871                         *cb->cutoff_cnt = cb->reccnt - 1;
 872                 /*
 873                  * we have not yet updated cb->[n|o]oid so they still
 874                  * hold the values for the previous record.
 875                  */
 876                 if (!is_null_oid(&cb->ooid)) {
 877                         oidcpy(cb->oid, noid);
 878                         if (oidcmp(&cb->ooid, noid))
 879                                 warning(_("log for ref %s has gap after %s"),
 880                                         cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
 881                 }
 882                 else if (cb->date == cb->at_time)
 883                         oidcpy(cb->oid, noid);
 884                 else if (oidcmp(noid, cb->oid))
 885                         warning(_("log for ref %s unexpectedly ended on %s"),
 886                                 cb->refname, show_date(cb->date, cb->tz,
 887                                                        DATE_MODE(RFC2822)));
 888                 oidcpy(&cb->ooid, ooid);
 889                 oidcpy(&cb->noid, noid);
 890                 cb->found_it = 1;
 891                 return 1;
 892         }
 893         oidcpy(&cb->ooid, ooid);
 894         oidcpy(&cb->noid, noid);
 895         if (cb->cnt > 0)
 896                 cb->cnt--;
 897         return 0;
 898 }
 899
 900 static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
 901                                   const char *email, timestamp_t timestamp,
 902                                   int tz, const char *message, void *cb_data)
 903 {
 904         struct read_ref_at_cb *cb = cb_data;
 905
 906         if (cb->msg)
 907                 *cb->msg = xstrdup(message);
 908         if (cb->cutoff_time)
 909                 *cb->cutoff_time = timestamp;
 910         if (cb->cutoff_tz)
 911                 *cb->cutoff_tz = tz;
 912         if (cb->cutoff_cnt)
 913                 *cb->cutoff_cnt = cb->reccnt;
 914         oidcpy(cb->oid, ooid);
 915         if (is_null_oid(cb->oid))
 916                 oidcpy(cb->oid, noid);
 917         /* We just want the first entry */
 918         return 1;
 919 }
 920
 921 int read_ref_at(const char *refname, unsigned int flags, timestamp_t at_time, int cnt,
 922                 struct object_id *oid, char **msg,
 923                 timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
 924 {
 925         struct read_ref_at_cb cb;
 926
 927         memset(&cb, 0, sizeof(cb));
 928         cb.refname = refname;
 929         cb.at_time = at_time;
 930         cb.cnt = cnt;
 931         cb.msg = msg;
 932         cb.cutoff_time = cutoff_time;
 933         cb.cutoff_tz = cutoff_tz;
 934         cb.cutoff_cnt = cutoff_cnt;
 935         cb.oid = oid;
 936
 937         for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
 938
 939         if (!cb.reccnt) {
 940                 if (flags & GET_OID_QUIETLY)
 941                         exit(128);
 942                 else
 943                         die(_("log for %s is empty"), refname);
 944         }
 945         if (cb.found_it)
 946                 return 0;
 947
 948         for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
 949
 950         return 1;
 951 }
 952
 953 struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs,
 954                                                     struct strbuf *err)
 955 {
 956         struct ref_transaction *tr;
 957         assert(err);
 958
 959         tr = xcalloc(1, sizeof(struct ref_transaction));
 960         tr->ref_store = refs;
 961         return tr;
 962 }
 963
 964 struct ref_transaction *ref_transaction_begin(struct strbuf *err)
 965 {
 966         return ref_store_transaction_begin(get_main_ref_store(the_repository), err);
 967 }
 968
 969 void ref_transaction_free(struct ref_transaction *transaction)
 970 {
 971         size_t i;
 972
 973         if (!transaction)
 974                 return;
 975
 976         switch (transaction->state) {
 977         case REF_TRANSACTION_OPEN:
 978         case REF_TRANSACTION_CLOSED:
 979                 /* OK */
 980                 break;
 981         case REF_TRANSACTION_PREPARED:
 982                 BUG("free called on a prepared reference transaction");
 983                 break;
 984         default:
 985                 BUG("unexpected reference transaction state");
 986                 break;
 987         }
 988
 989         for (i = 0; i < transaction->nr; i++) {
 990                 free(transaction->updates[i]->msg);
 991                 free(transaction->updates[i]);
 992         }
 993         free(transaction->updates);
 994         free(transaction);
 995 }
 996
 997 struct ref_update *ref_transaction_add_update(
 998                 struct ref_transaction *transaction,
 999                 const char *refname, unsigned int flags,
1000                 const struct object_id *new_oid,
1001                 const struct object_id *old_oid,
1002                 const char *msg)
1003 {
1004         struct ref_update *update;
1005
1006         if (transaction->state != REF_TRANSACTION_OPEN)
1007                 BUG("update called for transaction that is not open");
1008
1009         FLEX_ALLOC_STR(update, refname, refname);
1010         ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
1011         transaction->updates[transaction->nr++] = update;
1012
1013         update->flags = flags;
1014
1015         if (flags & REF_HAVE_NEW)
1016                 oidcpy(&update->new_oid, new_oid);
1017         if (flags & REF_HAVE_OLD)
1018                 oidcpy(&update->old_oid, old_oid);
1019         update->msg = xstrdup_or_null(msg);
1020         return update;
1021 }
1022
1023 int ref_transaction_update(struct ref_transaction *transaction,
1024                            const char *refname,
1025                            const struct object_id *new_oid,
1026                            const struct object_id *old_oid,
1027                            unsigned int flags, const char *msg,
1028                            struct strbuf *err)
1029 {
1030         assert(err);
1031
1032         if ((new_oid && !is_null_oid(new_oid)) ?
1033             check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
1034             !refname_is_safe(refname)) {
1035                 strbuf_addf(err, _("refusing to update ref with bad name '%s'"),
1036                             refname);
1037                 return -1;
1038         }
1039
1040         if (flags & ~REF_TRANSACTION_UPDATE_ALLOWED_FLAGS)
1041                 BUG("illegal flags 0x%x passed to ref_transaction_update()", flags);
1042
1043         flags |= (new_oid ? REF_HAVE_NEW : 0) | (old_oid ? REF_HAVE_OLD : 0);
1044
1045         ref_transaction_add_update(transaction, refname, flags,
1046                                    new_oid, old_oid, msg);
1047         return 0;
1048 }
1049
1050 int ref_transaction_create(struct ref_transaction *transaction,
1051                            const char *refname,
1052                            const struct object_id *new_oid,
1053                            unsigned int flags, const char *msg,
1054                            struct strbuf *err)
1055 {
1056         if (!new_oid || is_null_oid(new_oid))
1057                 BUG("create called without valid new_oid");
1058         return ref_transaction_update(transaction, refname, new_oid,
1059                                       &null_oid, flags, msg, err);
1060 }
1061
1062 int ref_transaction_delete(struct ref_transaction *transaction,
1063                            const char *refname,
1064                            const struct object_id *old_oid,
1065                            unsigned int flags, const char *msg,
1066                            struct strbuf *err)
1067 {
1068         if (old_oid && is_null_oid(old_oid))
1069                 BUG("delete called with old_oid set to zeros");
1070         return ref_transaction_update(transaction, refname,
1071                                       &null_oid, old_oid,
1072                                       flags, msg, err);
1073 }
1074
1075 int ref_transaction_verify(struct ref_transaction *transaction,
1076                            const char *refname,
1077                            const struct object_id *old_oid,
1078                            unsigned int flags,
1079                            struct strbuf *err)
1080 {
1081         if (!old_oid)
1082                 BUG("verify called with old_oid set to NULL");
1083         return ref_transaction_update(transaction, refname,
1084                                       NULL, old_oid,
1085                                       flags, NULL, err);
1086 }
1087
1088 int refs_update_ref(struct ref_store *refs, const char *msg,
1089                     const char *refname, const struct object_id *new_oid,
1090                     const struct object_id *old_oid, unsigned int flags,
1091                     enum action_on_err onerr)
1092 {
1093         struct ref_transaction *t = NULL;
1094         struct strbuf err = STRBUF_INIT;
1095         int ret = 0;
1096
1097         if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
1098                 assert(refs == get_main_ref_store(the_repository));
1099                 ret = write_pseudoref(refname, new_oid, old_oid, &err);
1100         } else {
1101                 t = ref_store_transaction_begin(refs, &err);
1102                 if (!t ||
1103                     ref_transaction_update(t, refname, new_oid, old_oid,
1104                                            flags, msg, &err) ||
1105                     ref_transaction_commit(t, &err)) {
1106                         ret = 1;
1107                         ref_transaction_free(t);
1108                 }
1109         }
1110         if (ret) {
1111                 const char *str = _("update_ref failed for ref '%s': %s");
1112
1113                 switch (onerr) {
1114                 case UPDATE_REFS_MSG_ON_ERR:
1115                         error(str, refname, err.buf);
1116                         break;
1117                 case UPDATE_REFS_DIE_ON_ERR:
1118                         die(str, refname, err.buf);
1119                         break;
1120                 case UPDATE_REFS_QUIET_ON_ERR:
1121                         break;
1122                 }
1123                 strbuf_release(&err);
1124                 return 1;
1125         }
1126         strbuf_release(&err);
1127         if (t)
1128                 ref_transaction_free(t);
1129         return 0;
1130 }
1131
1132 int update_ref(const char *msg, const char *refname,
1133                const struct object_id *new_oid,
1134                const struct object_id *old_oid,
1135                unsigned int flags, enum action_on_err onerr)
1136 {
1137         return refs_update_ref(get_main_ref_store(the_repository), msg, refname, new_oid,
1138                                old_oid, flags, onerr);
1139 }
1140
1141 char *shorten_unambiguous_ref(const char *refname, int strict)
1142 {
1143         int i;
1144         static char **scanf_fmts;
1145         static int nr_rules;
1146         char *short_name;
1147         struct strbuf resolved_buf = STRBUF_INIT;
1148
1149         if (!nr_rules) {
1150                 /*
1151                  * Pre-generate scanf formats from ref_rev_parse_rules[].
1152                  * Generate a format suitable for scanf from a
1153                  * ref_rev_parse_rules rule by interpolating "%s" at the
1154                  * location of the "%.*s".
1155                  */
1156                 size_t total_len = 0;
1157                 size_t offset = 0;
1158
1159                 /* the rule list is NULL terminated, count them first */
1160                 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
1161                         /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
1162                         total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
1163
1164                 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
1165
1166                 offset = 0;
1167                 for (i = 0; i < nr_rules; i++) {
1168                         assert(offset < total_len);
1169                         scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
1170                         offset += xsnprintf(scanf_fmts[i], total_len - offset,
1171                                             ref_rev_parse_rules[i], 2, "%s") + 1;
1172                 }
1173         }
1174
1175         /* bail out if there are no rules */
1176         if (!nr_rules)
1177                 return xstrdup(refname);
1178
1179         /* buffer for scanf result, at most refname must fit */
1180         short_name = xstrdup(refname);
1181
1182         /* skip first rule, it will always match */
1183         for (i = nr_rules - 1; i > 0 ; --i) {
1184                 int j;
1185                 int rules_to_fail = i;
1186                 int short_name_len;
1187
1188                 if (1 != sscanf(refname, scanf_fmts[i], short_name))
1189                         continue;
1190
1191                 short_name_len = strlen(short_name);
1192
1193                 /*
1194                  * in strict mode, all (except the matched one) rules
1195                  * must fail to resolve to a valid non-ambiguous ref
1196                  */
1197                 if (strict)
1198                         rules_to_fail = nr_rules;
1199
1200                 /*
1201                  * check if the short name resolves to a valid ref,
1202                  * but use only rules prior to the matched one
1203                  */
1204                 for (j = 0; j < rules_to_fail; j++) {
1205                         const char *rule = ref_rev_parse_rules[j];
1206
1207                         /* skip matched rule */
1208                         if (i == j)
1209                                 continue;
1210
1211                         /*
1212                          * the short name is ambiguous, if it resolves
1213                          * (with this previous rule) to a valid ref
1214                          * read_ref() returns 0 on success
1215                          */
1216                         strbuf_reset(&resolved_buf);
1217                         strbuf_addf(&resolved_buf, rule,
1218                                     short_name_len, short_name);
1219                         if (ref_exists(resolved_buf.buf))
1220                                 break;
1221                 }
1222
1223                 /*
1224                  * short name is non-ambiguous if all previous rules
1225                  * haven't resolved to a valid ref
1226                  */
1227                 if (j == rules_to_fail) {
1228                         strbuf_release(&resolved_buf);
1229                         return short_name;
1230                 }
1231         }
1232
1233         strbuf_release(&resolved_buf);
1234         free(short_name);
1235         return xstrdup(refname);
1236 }
1237
1238 static struct string_list *hide_refs;
1239
1240 int parse_hide_refs_config(const char *var, const char *value, const char *section)
1241 {
1242         const char *key;
1243         if (!strcmp("transfer.hiderefs", var) ||
1244             (!parse_config_key(var, section, NULL, NULL, &key) &&
1245              !strcmp(key, "hiderefs"))) {
1246                 char *ref;
1247                 int len;
1248
1249                 if (!value)
1250                         return config_error_nonbool(var);
1251                 ref = xstrdup(value);
1252                 len = strlen(ref);
1253                 while (len && ref[len - 1] == '/')
1254                         ref[--len] = '\0';
1255                 if (!hide_refs) {
1256                         hide_refs = xcalloc(1, sizeof(*hide_refs));
1257                         hide_refs->strdup_strings = 1;
1258                 }
1259                 string_list_append(hide_refs, ref);
1260         }
1261         return 0;
1262 }
1263
1264 int ref_is_hidden(const char *refname, const char *refname_full)
1265 {
1266         int i;
1267
1268         if (!hide_refs)
1269                 return 0;
1270         for (i = hide_refs->nr - 1; i >= 0; i--) {
1271                 const char *match = hide_refs->items[i].string;
1272                 const char *subject;
1273                 int neg = 0;
1274                 const char *p;
1275
1276                 if (*match == '!') {
1277                         neg = 1;
1278                         match++;
1279                 }
1280
1281                 if (*match == '^') {
1282                         subject = refname_full;
1283                         match++;
1284                 } else {
1285                         subject = refname;
1286                 }
1287
1288                 /* refname can be NULL when namespaces are used. */
1289                 if (subject &&
1290                     skip_prefix(subject, match, &p) &&
1291                     (!*p || *p == '/'))
1292                         return !neg;
1293         }
1294         return 0;
1295 }
1296
1297 const char *find_descendant_ref(const char *dirname,
1298                                 const struct string_list *extras,
1299                                 const struct string_list *skip)
1300 {
1301         int pos;
1302
1303         if (!extras)
1304                 return NULL;
1305
1306         /*
1307          * Look at the place where dirname would be inserted into
1308          * extras. If there is an entry at that position that starts
1309          * with dirname (remember, dirname includes the trailing
1310          * slash) and is not in skip, then we have a conflict.
1311          */
1312         for (pos = string_list_find_insert_index(extras, dirname, 0);
1313              pos < extras->nr; pos++) {
1314                 const char *extra_refname = extras->items[pos].string;
1315
1316                 if (!starts_with(extra_refname, dirname))
1317                         break;
1318
1319                 if (!skip || !string_list_has_string(skip, extra_refname))
1320                         return extra_refname;
1321         }
1322         return NULL;
1323 }
1324
1325 int refs_rename_ref_available(struct ref_store *refs,
1326                               const char *old_refname,
1327                               const char *new_refname)
1328 {
1329         struct string_list skip = STRING_LIST_INIT_NODUP;
1330         struct strbuf err = STRBUF_INIT;
1331         int ok;
1332
1333         string_list_insert(&skip, old_refname);
1334         ok = !refs_verify_refname_available(refs, new_refname,
1335                                             NULL, &skip, &err);
1336         if (!ok)
1337                 error("%s", err.buf);
1338
1339         string_list_clear(&skip, 0);
1340         strbuf_release(&err);
1341         return ok;
1342 }
1343
1344 int refs_head_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1345 {
1346         struct object_id oid;
1347         int flag;
1348
1349         if (!refs_read_ref_full(refs, "HEAD", RESOLVE_REF_READING,
1350                                 &oid, &flag))
1351                 return fn("HEAD", &oid, flag, cb_data);
1352
1353         return 0;
1354 }
1355
1356 int head_ref(each_ref_fn fn, void *cb_data)
1357 {
1358         return refs_head_ref(get_main_ref_store(the_repository), fn, cb_data);
1359 }
1360
1361 struct ref_iterator *refs_ref_iterator_begin(
1362                 struct ref_store *refs,
1363                 const char *prefix, int trim, int flags)
1364 {
1365         struct ref_iterator *iter;
1366
1367         if (ref_paranoia < 0)
1368                 ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
1369         if (ref_paranoia)
1370                 flags |= DO_FOR_EACH_INCLUDE_BROKEN;
1371
1372         iter = refs->be->iterator_begin(refs, prefix, flags);
1373
1374         /*
1375          * `iterator_begin()` already takes care of prefix, but we
1376          * might need to do some trimming:
1377          */
1378         if (trim)
1379                 iter = prefix_ref_iterator_begin(iter, "", trim);
1380
1381         /* Sanity check for subclasses: */
1382         if (!iter->ordered)
1383                 BUG("reference iterator is not ordered");
1384
1385         return iter;
1386 }
1387
1388 /*
1389  * Call fn for each reference in the specified submodule for which the
1390  * refname begins with prefix. If trim is non-zero, then trim that
1391  * many characters off the beginning of each refname before passing
1392  * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1393  * include broken references in the iteration. If fn ever returns a
1394  * non-zero value, stop the iteration and return that value;
1395  * otherwise, return 0.
1396  */
1397 static int do_for_each_repo_ref(struct repository *r, const char *prefix,
1398                                 each_repo_ref_fn fn, int trim, int flags,
1399                                 void *cb_data)
1400 {
1401         struct ref_iterator *iter;
1402         struct ref_store *refs = get_main_ref_store(r);
1403
1404         if (!refs)
1405                 return 0;
1406
1407         iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1408
1409         return do_for_each_repo_ref_iterator(r, iter, fn, cb_data);
1410 }
1411
1412 struct do_for_each_ref_help {
1413         each_ref_fn *fn;
1414         void *cb_data;
1415 };
1416
1417 static int do_for_each_ref_helper(struct repository *r,
1418                                   const char *refname,
1419                                   const struct object_id *oid,
1420                                   int flags,
1421                                   void *cb_data)
1422 {
1423         struct do_for_each_ref_help *hp = cb_data;
1424
1425         return hp->fn(refname, oid, flags, hp->cb_data);
1426 }
1427
1428 static int do_for_each_ref(struct ref_store *refs, const char *prefix,
1429                            each_ref_fn fn, int trim, int flags, void *cb_data)
1430 {
1431         struct ref_iterator *iter;
1432         struct do_for_each_ref_help hp = { fn, cb_data };
1433
1434         if (!refs)
1435                 return 0;
1436
1437         iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1438
1439         return do_for_each_repo_ref_iterator(the_repository, iter,
1440                                         do_for_each_ref_helper, &hp);
1441 }
1442
1443 int refs_for_each_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1444 {
1445         return do_for_each_ref(refs, "", fn, 0, 0, cb_data);
1446 }
1447
1448 int for_each_ref(each_ref_fn fn, void *cb_data)
1449 {
1450         return refs_for_each_ref(get_main_ref_store(the_repository), fn, cb_data);
1451 }
1452
1453 int refs_for_each_ref_in(struct ref_store *refs, const char *prefix,
1454                          each_ref_fn fn, void *cb_data)
1455 {
1456         return do_for_each_ref(refs, prefix, fn, strlen(prefix), 0, cb_data);
1457 }
1458
1459 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1460 {
1461         return refs_for_each_ref_in(get_main_ref_store(the_repository), prefix, fn, cb_data);
1462 }
1463
1464 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1465 {
1466         unsigned int flag = 0;
1467
1468         if (broken)
1469                 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1470         return do_for_each_ref(get_main_ref_store(the_repository),
1471                                prefix, fn, 0, flag, cb_data);
1472 }
1473
1474 int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix,
1475                              each_ref_fn fn, void *cb_data,
1476                              unsigned int broken)
1477 {
1478         unsigned int flag = 0;
1479
1480         if (broken)
1481                 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1482         return do_for_each_ref(refs, prefix, fn, 0, flag, cb_data);
1483 }
1484
1485 int for_each_replace_ref(struct repository *r, each_repo_ref_fn fn, void *cb_data)
1486 {
1487         return do_for_each_repo_ref(r, git_replace_ref_base, fn,
1488                                     strlen(git_replace_ref_base),
1489                                     DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1490 }
1491
1492 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1493 {
1494         struct strbuf buf = STRBUF_INIT;
1495         int ret;
1496         strbuf_addf(&buf, "%srefs/", get_git_namespace());
1497         ret = do_for_each_ref(get_main_ref_store(the_repository),
1498                               buf.buf, fn, 0, 0, cb_data);
1499         strbuf_release(&buf);
1500         return ret;
1501 }
1502
1503 int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1504 {
1505         return do_for_each_ref(refs, "", fn, 0,
1506                                DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1507 }
1508
1509 int for_each_rawref(each_ref_fn fn, void *cb_data)
1510 {
1511         return refs_for_each_rawref(get_main_ref_store(the_repository), fn, cb_data);
1512 }
1513
1514 int refs_read_raw_ref(struct ref_store *ref_store,
1515                       const char *refname, struct object_id *oid,
1516                       struct strbuf *referent, unsigned int *type)
1517 {
1518         return ref_store->be->read_raw_ref(ref_store, refname, oid, referent, type);
1519 }
1520
1521 /* This function needs to return a meaningful errno on failure */
1522 const char *refs_resolve_ref_unsafe(struct ref_store *refs,
1523                                     const char *refname,
1524                                     int resolve_flags,
1525                                     struct object_id *oid, int *flags)
1526 {
1527         static struct strbuf sb_refname = STRBUF_INIT;
1528         struct object_id unused_oid;
1529         int unused_flags;
1530         int symref_count;
1531
1532         if (!oid)
1533                 oid = &unused_oid;
1534         if (!flags)
1535                 flags = &unused_flags;
1536
1537         *flags = 0;
1538
1539         if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1540                 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1541                     !refname_is_safe(refname)) {
1542                         errno = EINVAL;
1543                         return NULL;
1544                 }
1545
1546                 /*
1547                  * dwim_ref() uses REF_ISBROKEN to distinguish between
1548                  * missing refs and refs that were present but invalid,
1549                  * to complain about the latter to stderr.
1550                  *
1551                  * We don't know whether the ref exists, so don't set
1552                  * REF_ISBROKEN yet.
1553                  */
1554                 *flags |= REF_BAD_NAME;
1555         }
1556
1557         for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1558                 unsigned int read_flags = 0;
1559
1560                 if (refs_read_raw_ref(refs, refname,
1561                                       oid, &sb_refname, &read_flags)) {
1562                         *flags |= read_flags;
1563
1564                         /* In reading mode, refs must eventually resolve */
1565                         if (resolve_flags & RESOLVE_REF_READING)
1566                                 return NULL;
1567
1568                         /*
1569                          * Otherwise a missing ref is OK. But the files backend
1570                          * may show errors besides ENOENT if there are
1571                          * similarly-named refs.
1572                          */
1573                         if (errno != ENOENT &&
1574                             errno != EISDIR &&
1575                             errno != ENOTDIR)
1576                                 return NULL;
1577
1578                         oidclr(oid);
1579                         if (*flags & REF_BAD_NAME)
1580                                 *flags |= REF_ISBROKEN;
1581                         return refname;
1582                 }
1583
1584                 *flags |= read_flags;
1585
1586                 if (!(read_flags & REF_ISSYMREF)) {
1587                         if (*flags & REF_BAD_NAME) {
1588                                 oidclr(oid);
1589                                 *flags |= REF_ISBROKEN;
1590                         }
1591                         return refname;
1592                 }
1593
1594                 refname = sb_refname.buf;
1595                 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1596                         oidclr(oid);
1597                         return refname;
1598                 }
1599                 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1600                         if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1601                             !refname_is_safe(refname)) {
1602                                 errno = EINVAL;
1603                                 return NULL;
1604                         }
1605
1606                         *flags |= REF_ISBROKEN | REF_BAD_NAME;
1607                 }
1608         }
1609
1610         errno = ELOOP;
1611         return NULL;
1612 }
1613
1614 /* backend functions */
1615 int refs_init_db(struct strbuf *err)
1616 {
1617         struct ref_store *refs = get_main_ref_store(the_repository);
1618
1619         return refs->be->init_db(refs, err);
1620 }
1621
1622 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1623                                struct object_id *oid, int *flags)
1624 {
1625         return refs_resolve_ref_unsafe(get_main_ref_store(the_repository), refname,
1626                                        resolve_flags, oid, flags);
1627 }
1628
1629 int resolve_gitlink_ref(const char *submodule, const char *refname,
1630                         struct object_id *oid)
1631 {
1632         struct ref_store *refs;
1633         int flags;
1634
1635         refs = get_submodule_ref_store(submodule);
1636
1637         if (!refs)
1638                 return -1;
1639
1640         if (!refs_resolve_ref_unsafe(refs, refname, 0, oid, &flags) ||
1641             is_null_oid(oid))
1642                 return -1;
1643         return 0;
1644 }
1645
1646 struct ref_store_hash_entry
1647 {
1648         struct hashmap_entry ent; /* must be the first member! */
1649
1650         struct ref_store *refs;
1651
1652         /* NUL-terminated identifier of the ref store: */
1653         char name[FLEX_ARRAY];
1654 };
1655
1656 static int ref_store_hash_cmp(const void *unused_cmp_data,
1657                               const void *entry, const void *entry_or_key,
1658                               const void *keydata)
1659 {
1660         const struct ref_store_hash_entry *e1 = entry, *e2 = entry_or_key;
1661         const char *name = keydata ? keydata : e2->name;
1662
1663         return strcmp(e1->name, name);
1664 }
1665
1666 static struct ref_store_hash_entry *alloc_ref_store_hash_entry(
1667                 const char *name, struct ref_store *refs)
1668 {
1669         struct ref_store_hash_entry *entry;
1670
1671         FLEX_ALLOC_STR(entry, name, name);
1672         hashmap_entry_init(entry, strhash(name));
1673         entry->refs = refs;
1674         return entry;
1675 }
1676
1677 /* A hashmap of ref_stores, stored by submodule name: */
1678 static struct hashmap submodule_ref_stores;
1679
1680 /* A hashmap of ref_stores, stored by worktree id: */
1681 static struct hashmap worktree_ref_stores;
1682
1683 /*
1684  * Look up a ref store by name. If that ref_store hasn't been
1685  * registered yet, return NULL.
1686  */
1687 static struct ref_store *lookup_ref_store_map(struct hashmap *map,
1688                                               const char *name)
1689 {
1690         struct ref_store_hash_entry *entry;
1691
1692         if (!map->tablesize)
1693                 /* It's initialized on demand in register_ref_store(). */
1694                 return NULL;
1695
1696         entry = hashmap_get_from_hash(map, strhash(name), name);
1697         return entry ? entry->refs : NULL;
1698 }
1699
1700 /*
1701  * Create, record, and return a ref_store instance for the specified
1702  * gitdir.
1703  */
1704 static struct ref_store *ref_store_init(const char *gitdir,
1705                                         unsigned int flags)
1706 {
1707         const char *be_name = "files";
1708         struct ref_storage_be *be = find_ref_storage_backend(be_name);
1709         struct ref_store *refs;
1710
1711         if (!be)
1712                 BUG("reference backend %s is unknown", be_name);
1713
1714         refs = be->init(gitdir, flags);
1715         return refs;
1716 }
1717
1718 struct ref_store *get_main_ref_store(struct repository *r)
1719 {
1720         if (r->refs)
1721                 return r->refs;
1722
1723         if (!r->gitdir)
1724                 BUG("attempting to get main_ref_store outside of repository");
1725
1726         r->refs = ref_store_init(r->gitdir, REF_STORE_ALL_CAPS);
1727         return r->refs;
1728 }
1729
1730 /*
1731  * Associate a ref store with a name. It is a fatal error to call this
1732  * function twice for the same name.
1733  */
1734 static void register_ref_store_map(struct hashmap *map,
1735                                    const char *type,
1736                                    struct ref_store *refs,
1737                                    const char *name)
1738 {
1739         if (!map->tablesize)
1740                 hashmap_init(map, ref_store_hash_cmp, NULL, 0);
1741
1742         if (hashmap_put(map, alloc_ref_store_hash_entry(name, refs)))
1743                 BUG("%s ref_store '%s' initialized twice", type, name);
1744 }
1745
1746 struct ref_store *get_submodule_ref_store(const char *submodule)
1747 {
1748         struct strbuf submodule_sb = STRBUF_INIT;
1749         struct ref_store *refs;
1750         char *to_free = NULL;
1751         size_t len;
1752
1753         if (!submodule)
1754                 return NULL;
1755
1756         len = strlen(submodule);
1757         while (len && is_dir_sep(submodule[len - 1]))
1758                 len--;
1759         if (!len)
1760                 return NULL;
1761
1762         if (submodule[len])
1763                 /* We need to strip off one or more trailing slashes */
1764                 submodule = to_free = xmemdupz(submodule, len);
1765
1766         refs = lookup_ref_store_map(&submodule_ref_stores, submodule);
1767         if (refs)
1768                 goto done;
1769
1770         strbuf_addstr(&submodule_sb, submodule);
1771         if (!is_nonbare_repository_dir(&submodule_sb))
1772                 goto done;
1773
1774         if (submodule_to_gitdir(&submodule_sb, submodule))
1775                 goto done;
1776
1777         /* assume that add_submodule_odb() has been called */
1778         refs = ref_store_init(submodule_sb.buf,
1779                               REF_STORE_READ | REF_STORE_ODB);
1780         register_ref_store_map(&submodule_ref_stores, "submodule",
1781                                refs, submodule);
1782
1783 done:
1784         strbuf_release(&submodule_sb);
1785         free(to_free);
1786
1787         return refs;
1788 }
1789
1790 struct ref_store *get_worktree_ref_store(const struct worktree *wt)
1791 {
1792         struct ref_store *refs;
1793         const char *id;
1794
1795         if (wt->is_current)
1796                 return get_main_ref_store(the_repository);
1797
1798         id = wt->id ? wt->id : "/";
1799         refs = lookup_ref_store_map(&worktree_ref_stores, id);
1800         if (refs)
1801                 return refs;
1802
1803         if (wt->id)
1804                 refs = ref_store_init(git_common_path("worktrees/%s", wt->id),
1805                                       REF_STORE_ALL_CAPS);
1806         else
1807                 refs = ref_store_init(get_git_common_dir(),
1808                                       REF_STORE_ALL_CAPS);
1809
1810         if (refs)
1811                 register_ref_store_map(&worktree_ref_stores, "worktree",
1812                                        refs, id);
1813         return refs;
1814 }
1815
1816 void base_ref_store_init(struct ref_store *refs,
1817                          const struct ref_storage_be *be)
1818 {
1819         refs->be = be;
1820 }
1821
1822 /* backend functions */
1823 int refs_pack_refs(struct ref_store *refs, unsigned int flags)
1824 {
1825         return refs->be->pack_refs(refs, flags);
1826 }
1827
1828 int refs_peel_ref(struct ref_store *refs, const char *refname,
1829                   struct object_id *oid)
1830 {
1831         int flag;
1832         struct object_id base;
1833
1834         if (current_ref_iter && current_ref_iter->refname == refname) {
1835                 struct object_id peeled;
1836
1837                 if (ref_iterator_peel(current_ref_iter, &peeled))
1838                         return -1;
1839                 oidcpy(oid, &peeled);
1840                 return 0;
1841         }
1842
1843         if (refs_read_ref_full(refs, refname,
1844                                RESOLVE_REF_READING, &base, &flag))
1845                 return -1;
1846
1847         return peel_object(&base, oid);
1848 }
1849
1850 int peel_ref(const char *refname, struct object_id *oid)
1851 {
1852         return refs_peel_ref(get_main_ref_store(the_repository), refname, oid);
1853 }
1854
1855 int refs_create_symref(struct ref_store *refs,
1856                        const char *ref_target,
1857                        const char *refs_heads_master,
1858                        const char *logmsg)
1859 {
1860         return refs->be->create_symref(refs, ref_target,
1861                                        refs_heads_master,
1862                                        logmsg);
1863 }
1864
1865 int create_symref(const char *ref_target, const char *refs_heads_master,
1866                   const char *logmsg)
1867 {
1868         return refs_create_symref(get_main_ref_store(the_repository), ref_target,
1869                                   refs_heads_master, logmsg);
1870 }
1871
1872 int ref_update_reject_duplicates(struct string_list *refnames,
1873                                  struct strbuf *err)
1874 {
1875         size_t i, n = refnames->nr;
1876
1877         assert(err);
1878
1879         for (i = 1; i < n; i++) {
1880                 int cmp = strcmp(refnames->items[i - 1].string,
1881                                  refnames->items[i].string);
1882
1883                 if (!cmp) {
1884                         strbuf_addf(err,
1885                                     _("multiple updates for ref '%s' not allowed"),
1886                                     refnames->items[i].string);
1887                         return 1;
1888                 } else if (cmp > 0) {
1889                         BUG("ref_update_reject_duplicates() received unsorted list");
1890                 }
1891         }
1892         return 0;
1893 }
1894
1895 int ref_transaction_prepare(struct ref_transaction *transaction,
1896                             struct strbuf *err)
1897 {
1898         struct ref_store *refs = transaction->ref_store;
1899
1900         switch (transaction->state) {
1901         case REF_TRANSACTION_OPEN:
1902                 /* Good. */
1903                 break;
1904         case REF_TRANSACTION_PREPARED:
1905                 BUG("prepare called twice on reference transaction");
1906                 break;
1907         case REF_TRANSACTION_CLOSED:
1908                 BUG("prepare called on a closed reference transaction");
1909                 break;
1910         default:
1911                 BUG("unexpected reference transaction state");
1912                 break;
1913         }
1914
1915         if (getenv(GIT_QUARANTINE_ENVIRONMENT)) {
1916                 strbuf_addstr(err,
1917                               _("ref updates forbidden inside quarantine environment"));
1918                 return -1;
1919         }
1920
1921         return refs->be->transaction_prepare(refs, transaction, err);
1922 }
1923
1924 int ref_transaction_abort(struct ref_transaction *transaction,
1925                           struct strbuf *err)
1926 {
1927         struct ref_store *refs = transaction->ref_store;
1928         int ret = 0;
1929
1930         switch (transaction->state) {
1931         case REF_TRANSACTION_OPEN:
1932                 /* No need to abort explicitly. */
1933                 break;
1934         case REF_TRANSACTION_PREPARED:
1935                 ret = refs->be->transaction_abort(refs, transaction, err);
1936                 break;
1937         case REF_TRANSACTION_CLOSED:
1938                 BUG("abort called on a closed reference transaction");
1939                 break;
1940         default:
1941                 BUG("unexpected reference transaction state");
1942                 break;
1943         }
1944
1945         ref_transaction_free(transaction);
1946         return ret;
1947 }
1948
1949 int ref_transaction_commit(struct ref_transaction *transaction,
1950                            struct strbuf *err)
1951 {
1952         struct ref_store *refs = transaction->ref_store;
1953         int ret;
1954
1955         switch (transaction->state) {
1956         case REF_TRANSACTION_OPEN:
1957                 /* Need to prepare first. */
1958                 ret = ref_transaction_prepare(transaction, err);
1959                 if (ret)
1960                         return ret;
1961                 break;
1962         case REF_TRANSACTION_PREPARED:
1963                 /* Fall through to finish. */
1964                 break;
1965         case REF_TRANSACTION_CLOSED:
1966                 BUG("commit called on a closed reference transaction");
1967                 break;
1968         default:
1969                 BUG("unexpected reference transaction state");
1970                 break;
1971         }
1972
1973         return refs->be->transaction_finish(refs, transaction, err);
1974 }
1975
1976 int refs_verify_refname_available(struct ref_store *refs,
1977                                   const char *refname,
1978                                   const struct string_list *extras,
1979                                   const struct string_list *skip,
1980                                   struct strbuf *err)
1981 {
1982         const char *slash;
1983         const char *extra_refname;
1984         struct strbuf dirname = STRBUF_INIT;
1985         struct strbuf referent = STRBUF_INIT;
1986         struct object_id oid;
1987         unsigned int type;
1988         struct ref_iterator *iter;
1989         int ok;
1990         int ret = -1;
1991
1992         /*
1993          * For the sake of comments in this function, suppose that
1994          * refname is "refs/foo/bar".
1995          */
1996
1997         assert(err);
1998
1999         strbuf_grow(&dirname, strlen(refname) + 1);
2000         for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
2001                 /* Expand dirname to the new prefix, not including the trailing slash: */
2002                 strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
2003
2004                 /*
2005                  * We are still at a leading dir of the refname (e.g.,
2006                  * "refs/foo"; if there is a reference with that name,
2007                  * it is a conflict, *unless* it is in skip.
2008                  */
2009                 if (skip && string_list_has_string(skip, dirname.buf))
2010                         continue;
2011
2012                 if (!refs_read_raw_ref(refs, dirname.buf, &oid, &referent, &type)) {
2013                         strbuf_addf(err, _("'%s' exists; cannot create '%s'"),
2014                                     dirname.buf, refname);
2015                         goto cleanup;
2016                 }
2017
2018                 if (extras && string_list_has_string(extras, dirname.buf)) {
2019                         strbuf_addf(err, _("cannot process '%s' and '%s' at the same time"),
2020                                     refname, dirname.buf);
2021                         goto cleanup;
2022                 }
2023         }
2024
2025         /*
2026          * We are at the leaf of our refname (e.g., "refs/foo/bar").
2027          * There is no point in searching for a reference with that
2028          * name, because a refname isn't considered to conflict with
2029          * itself. But we still need to check for references whose
2030          * names are in the "refs/foo/bar/" namespace, because they
2031          * *do* conflict.
2032          */
2033         strbuf_addstr(&dirname, refname + dirname.len);
2034         strbuf_addch(&dirname, '/');
2035
2036         iter = refs_ref_iterator_begin(refs, dirname.buf, 0,
2037                                        DO_FOR_EACH_INCLUDE_BROKEN);
2038         while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
2039                 if (skip &&
2040                     string_list_has_string(skip, iter->refname))
2041                         continue;
2042
2043                 strbuf_addf(err, _("'%s' exists; cannot create '%s'"),
2044                             iter->refname, refname);
2045                 ref_iterator_abort(iter);
2046                 goto cleanup;
2047         }
2048
2049         if (ok != ITER_DONE)
2050                 BUG("error while iterating over references");
2051
2052         extra_refname = find_descendant_ref(dirname.buf, extras, skip);
2053         if (extra_refname)
2054                 strbuf_addf(err, _("cannot process '%s' and '%s' at the same time"),
2055                             refname, extra_refname);
2056         else
2057                 ret = 0;
2058
2059 cleanup:
2060         strbuf_release(&referent);
2061         strbuf_release(&dirname);
2062         return ret;
2063 }
2064
2065 int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2066 {
2067         struct ref_iterator *iter;
2068         struct do_for_each_ref_help hp = { fn, cb_data };
2069
2070         iter = refs->be->reflog_iterator_begin(refs);
2071
2072         return do_for_each_repo_ref_iterator(the_repository, iter,
2073                                              do_for_each_ref_helper, &hp);
2074 }
2075
2076 int for_each_reflog(each_ref_fn fn, void *cb_data)
2077 {
2078         return refs_for_each_reflog(get_main_ref_store(the_repository), fn, cb_data);
2079 }
2080
2081 int refs_for_each_reflog_ent_reverse(struct ref_store *refs,
2082                                      const char *refname,
2083                                      each_reflog_ent_fn fn,
2084                                      void *cb_data)
2085 {
2086         return refs->be->for_each_reflog_ent_reverse(refs, refname,
2087                                                      fn, cb_data);
2088 }
2089
2090 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
2091                                 void *cb_data)
2092 {
2093         return refs_for_each_reflog_ent_reverse(get_main_ref_store(the_repository),
2094                                                 refname, fn, cb_data);
2095 }
2096
2097 int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname,
2098                              each_reflog_ent_fn fn, void *cb_data)
2099 {
2100         return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
2101 }
2102
2103 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
2104                         void *cb_data)
2105 {
2106         return refs_for_each_reflog_ent(get_main_ref_store(the_repository), refname,
2107                                         fn, cb_data);
2108 }
2109
2110 int refs_reflog_exists(struct ref_store *refs, const char *refname)
2111 {
2112         return refs->be->reflog_exists(refs, refname);
2113 }
2114
2115 int reflog_exists(const char *refname)
2116 {
2117         return refs_reflog_exists(get_main_ref_store(the_repository), refname);
2118 }
2119
2120 int refs_create_reflog(struct ref_store *refs, const char *refname,
2121                        int force_create, struct strbuf *err)
2122 {
2123         return refs->be->create_reflog(refs, refname, force_create, err);
2124 }
2125
2126 int safe_create_reflog(const char *refname, int force_create,
2127                        struct strbuf *err)
2128 {
2129         return refs_create_reflog(get_main_ref_store(the_repository), refname,
2130                                   force_create, err);
2131 }
2132
2133 int refs_delete_reflog(struct ref_store *refs, const char *refname)
2134 {
2135         return refs->be->delete_reflog(refs, refname);
2136 }
2137
2138 int delete_reflog(const char *refname)
2139 {
2140         return refs_delete_reflog(get_main_ref_store(the_repository), refname);
2141 }
2142
2143 int refs_reflog_expire(struct ref_store *refs,
2144                        const char *refname, const struct object_id *oid,
2145                        unsigned int flags,
2146                        reflog_expiry_prepare_fn prepare_fn,
2147                        reflog_expiry_should_prune_fn should_prune_fn,
2148                        reflog_expiry_cleanup_fn cleanup_fn,
2149                        void *policy_cb_data)
2150 {
2151         return refs->be->reflog_expire(refs, refname, oid, flags,
2152                                        prepare_fn, should_prune_fn,
2153                                        cleanup_fn, policy_cb_data);
2154 }
2155
2156 int reflog_expire(const char *refname, const struct object_id *oid,
2157                   unsigned int flags,
2158                   reflog_expiry_prepare_fn prepare_fn,
2159                   reflog_expiry_should_prune_fn should_prune_fn,
2160                   reflog_expiry_cleanup_fn cleanup_fn,
2161                   void *policy_cb_data)
2162 {
2163         return refs_reflog_expire(get_main_ref_store(the_repository),
2164                                   refname, oid, flags,
2165                                   prepare_fn, should_prune_fn,
2166                                   cleanup_fn, policy_cb_data);
2167 }
2168
2169 int initial_ref_transaction_commit(struct ref_transaction *transaction,
2170                                    struct strbuf *err)
2171 {
2172         struct ref_store *refs = transaction->ref_store;
2173
2174         return refs->be->initial_transaction_commit(refs, transaction, err);
2175 }
2176
2177 int refs_delete_refs(struct ref_store *refs, const char *msg,
2178                      struct string_list *refnames, unsigned int flags)
2179 {
2180         return refs->be->delete_refs(refs, msg, refnames, flags);
2181 }
2182
2183 int delete_refs(const char *msg, struct string_list *refnames,
2184                 unsigned int flags)
2185 {
2186         return refs_delete_refs(get_main_ref_store(the_repository), msg, refnames, flags);
2187 }
2188
2189 int refs_rename_ref(struct ref_store *refs, const char *oldref,
2190                     const char *newref, const char *logmsg)
2191 {
2192         return refs->be->rename_ref(refs, oldref, newref, logmsg);
2193 }
2194
2195 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
2196 {
2197         return refs_rename_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2198 }
2199
2200 int refs_copy_existing_ref(struct ref_store *refs, const char *oldref,
2201                     const char *newref, const char *logmsg)
2202 {
2203         return refs->be->copy_ref(refs, oldref, newref, logmsg);
2204 }
2205
2206 int copy_existing_ref(const char *oldref, const char *newref, const char *logmsg)
2207 {
2208         return refs_copy_existing_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2209 }