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