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 "repository.h"
  18
  19 /*
  20  * List of all available backends
  21  */
  22 static struct ref_storage_be *refs_backends = &refs_be_files;
  23
  24 static struct ref_storage_be *find_ref_storage_backend(const char *name)
  25 {
  26         struct ref_storage_be *be;
  27         for (be = refs_backends; be; be = be->next)
  28                 if (!strcmp(be->name, name))
  29                         return be;
  30         return NULL;
  31 }
  32
  33 int ref_storage_backend_exists(const char *name)
  34 {
  35         return find_ref_storage_backend(name) != NULL;
  36 }
  37
  38 /*
  39  * How to handle various characters in refnames:
  40  * 0: An acceptable character for refs
  41  * 1: End-of-component
  42  * 2: ., look for a preceding . to reject .. in refs
  43  * 3: {, look for a preceding @ to reject @{ in refs
  44  * 4: A bad character: ASCII control characters, and
  45  *    ":", "?", "[", "\", "^", "~", SP, or TAB
  46  * 5: *, reject unless REFNAME_REFSPEC_PATTERN is set
  47  */
  48 static unsigned char refname_disposition[256] = {
  49         1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
  50         4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
  51         4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 2, 1,
  52         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4,
  53         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  54         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 4, 0,
  55         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  56         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 4
  57 };
  58
  59 /*
  60  * Try to read one refname component from the front of refname.
  61  * Return the length of the component found, or -1 if the component is
  62  * not legal.  It is legal if it is something reasonable to have under
  63  * ".git/refs/"; We do not like it if:
  64  *
  65  * - any path component of it begins with ".", or
  66  * - it has double dots "..", or
  67  * - it has ASCII control characters, or
  68  * - it has ":", "?", "[", "\", "^", "~", SP, or TAB anywhere, or
  69  * - it has "*" anywhere unless REFNAME_REFSPEC_PATTERN is set, or
  70  * - it ends with a "/", or
  71  * - it ends with ".lock", or
  72  * - it contains a "@{" portion
  73  */
  74 static int check_refname_component(const char *refname, int *flags)
  75 {
  76         const char *cp;
  77         char last = '\0';
  78
  79         for (cp = refname; ; cp++) {
  80                 int ch = *cp & 255;
  81                 unsigned char disp = refname_disposition[ch];
  82                 switch (disp) {
  83                 case 1:
  84                         goto out;
  85                 case 2:
  86                         if (last == '.')
  87                                 return -1; /* Refname contains "..". */
  88                         break;
  89                 case 3:
  90                         if (last == '@')
  91                                 return -1; /* Refname contains "@{". */
  92                         break;
  93                 case 4:
  94                         return -1;
  95                 case 5:
  96                         if (!(*flags & REFNAME_REFSPEC_PATTERN))
  97                                 return -1; /* refspec can't be a pattern */
  98
  99                         /*
 100                          * Unset the pattern flag so that we only accept
 101                          * a single asterisk for one side of refspec.
 102                          */
 103                         *flags &= ~ REFNAME_REFSPEC_PATTERN;
 104                         break;
 105                 }
 106                 last = ch;
 107         }
 108 out:
 109         if (cp == refname)
 110                 return 0; /* Component has zero length. */
 111         if (refname[0] == '.')
 112                 return -1; /* Component starts with '.'. */
 113         if (cp - refname >= LOCK_SUFFIX_LEN &&
 114             !memcmp(cp - LOCK_SUFFIX_LEN, LOCK_SUFFIX, LOCK_SUFFIX_LEN))
 115                 return -1; /* Refname ends with ".lock". */
 116         return cp - refname;
 117 }
 118
 119 int check_refname_format(const char *refname, int flags)
 120 {
 121         int component_len, component_count = 0;
 122
 123         if (!strcmp(refname, "@"))
 124                 /* Refname is a single character '@'. */
 125                 return -1;
 126
 127         while (1) {
 128                 /* We are at the start of a path component. */
 129                 component_len = check_refname_component(refname, &flags);
 130                 if (component_len <= 0)
 131                         return -1;
 132
 133                 component_count++;
 134                 if (refname[component_len] == '\0')
 135                         break;
 136                 /* Skip to next component. */
 137                 refname += component_len + 1;
 138         }
 139
 140         if (refname[component_len - 1] == '.')
 141                 return -1; /* Refname ends with '.'. */
 142         if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
 143                 return -1; /* Refname has only one component. */
 144         return 0;
 145 }
 146
 147 int refname_is_safe(const char *refname)
 148 {
 149         const char *rest;
 150
 151         if (skip_prefix(refname, "refs/", &rest)) {
 152                 char *buf;
 153                 int result;
 154                 size_t restlen = strlen(rest);
 155
 156                 /* rest must not be empty, or start or end with "/" */
 157                 if (!restlen || *rest == '/' || rest[restlen - 1] == '/')
 158                         return 0;
 159
 160                 /*
 161                  * Does the refname try to escape refs/?
 162                  * For example: refs/foo/../bar is safe but refs/foo/../../bar
 163                  * is not.
 164                  */
 165                 buf = xmallocz(restlen);
 166                 result = !normalize_path_copy(buf, rest) && !strcmp(buf, rest);
 167                 free(buf);
 168                 return result;
 169         }
 170
 171         do {
 172                 if (!isupper(*refname) && *refname != '_')
 173                         return 0;
 174                 refname++;
 175         } while (*refname);
 176         return 1;
 177 }
 178
 179 /*
 180  * Return true if refname, which has the specified oid and flags, can
 181  * be resolved to an object in the database. If the referred-to object
 182  * does not exist, emit a warning and return false.
 183  */
 184 int ref_resolves_to_object(const char *refname,
 185                            const struct object_id *oid,
 186                            unsigned int flags)
 187 {
 188         if (flags & REF_ISBROKEN)
 189                 return 0;
 190         if (!has_sha1_file(oid->hash)) {
 191                 error("%s does not point to a valid object!", refname);
 192                 return 0;
 193         }
 194         return 1;
 195 }
 196
 197 char *refs_resolve_refdup(struct ref_store *refs,
 198                           const char *refname, int resolve_flags,
 199                           struct object_id *oid, int *flags)
 200 {
 201         const char *result;
 202
 203         result = refs_resolve_ref_unsafe(refs, refname, resolve_flags,
 204                                          oid, flags);
 205         return xstrdup_or_null(result);
 206 }
 207
 208 char *resolve_refdup(const char *refname, int resolve_flags,
 209                      struct object_id *oid, int *flags)
 210 {
 211         return refs_resolve_refdup(get_main_ref_store(the_repository),
 212                                    refname, resolve_flags,
 213                                    oid, flags);
 214 }
 215
 216 /* The argument to filter_refs */
 217 struct ref_filter {
 218         const char *pattern;
 219         each_ref_fn *fn;
 220         void *cb_data;
 221 };
 222
 223 int refs_read_ref_full(struct ref_store *refs, const char *refname,
 224                        int resolve_flags, struct object_id *oid, int *flags)
 225 {
 226         if (refs_resolve_ref_unsafe(refs, refname, resolve_flags, oid, flags))
 227                 return 0;
 228         return -1;
 229 }
 230
 231 int read_ref_full(const char *refname, int resolve_flags, struct object_id *oid, int *flags)
 232 {
 233         return refs_read_ref_full(get_main_ref_store(the_repository), refname,
 234                                   resolve_flags, oid, flags);
 235 }
 236
 237 int read_ref(const char *refname, struct object_id *oid)
 238 {
 239         return read_ref_full(refname, RESOLVE_REF_READING, oid, NULL);
 240 }
 241
 242 int ref_exists(const char *refname)
 243 {
 244         return !!resolve_ref_unsafe(refname, RESOLVE_REF_READING, NULL, NULL);
 245 }
 246
 247 static int match_ref_pattern(const char *refname,
 248                              const struct string_list_item *item)
 249 {
 250         int matched = 0;
 251         if (item->util == NULL) {
 252                 if (!wildmatch(item->string, refname, 0))
 253                         matched = 1;
 254         } else {
 255                 const char *rest;
 256                 if (skip_prefix(refname, item->string, &rest) &&
 257                     (!*rest || *rest == '/'))
 258                         matched = 1;
 259         }
 260         return matched;
 261 }
 262
 263 int ref_filter_match(const char *refname,
 264                      const struct string_list *include_patterns,
 265                      const struct string_list *exclude_patterns)
 266 {
 267         struct string_list_item *item;
 268
 269         if (exclude_patterns && exclude_patterns->nr) {
 270                 for_each_string_list_item(item, exclude_patterns) {
 271                         if (match_ref_pattern(refname, item))
 272                                 return 0;
 273                 }
 274         }
 275
 276         if (include_patterns && include_patterns->nr) {
 277                 int found = 0;
 278                 for_each_string_list_item(item, include_patterns) {
 279                         if (match_ref_pattern(refname, item)) {
 280                                 found = 1;
 281                                 break;
 282                         }
 283                 }
 284
 285                 if (!found)
 286                         return 0;
 287         }
 288         return 1;
 289 }
 290
 291 static int filter_refs(const char *refname, const struct object_id *oid,
 292                            int flags, void *data)
 293 {
 294         struct ref_filter *filter = (struct ref_filter *)data;
 295
 296         if (wildmatch(filter->pattern, refname, 0))
 297                 return 0;
 298         return filter->fn(refname, oid, flags, filter->cb_data);
 299 }
 300
 301 enum peel_status peel_object(const struct object_id *name, struct object_id *oid)
 302 {
 303         struct object *o = lookup_unknown_object(name->hash);
 304
 305         if (o->type == OBJ_NONE) {
 306                 int type = oid_object_info(the_repository, name, NULL);
 307                 if (type < 0 || !object_as_type(o, type, 0))
 308                         return PEEL_INVALID;
 309         }
 310
 311         if (o->type != OBJ_TAG)
 312                 return PEEL_NON_TAG;
 313
 314         o = deref_tag_noverify(o);
 315         if (!o)
 316                 return PEEL_INVALID;
 317
 318         oidcpy(oid, &o->oid);
 319         return PEEL_PEELED;
 320 }
 321
 322 struct warn_if_dangling_data {
 323         FILE *fp;
 324         const char *refname;
 325         const struct string_list *refnames;
 326         const char *msg_fmt;
 327 };
 328
 329 static int warn_if_dangling_symref(const char *refname, const struct object_id *oid,
 330                                    int flags, void *cb_data)
 331 {
 332         struct warn_if_dangling_data *d = cb_data;
 333         const char *resolves_to;
 334
 335         if (!(flags & REF_ISSYMREF))
 336                 return 0;
 337
 338         resolves_to = resolve_ref_unsafe(refname, 0, NULL, NULL);
 339         if (!resolves_to
 340             || (d->refname
 341                 ? strcmp(resolves_to, d->refname)
 342                 : !string_list_has_string(d->refnames, resolves_to))) {
 343                 return 0;
 344         }
 345
 346         fprintf(d->fp, d->msg_fmt, refname);
 347         fputc('\n', d->fp);
 348         return 0;
 349 }
 350
 351 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
 352 {
 353         struct warn_if_dangling_data data;
 354
 355         data.fp = fp;
 356         data.refname = refname;
 357         data.refnames = NULL;
 358         data.msg_fmt = msg_fmt;
 359         for_each_rawref(warn_if_dangling_symref, &data);
 360 }
 361
 362 void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames)
 363 {
 364         struct warn_if_dangling_data data;
 365
 366         data.fp = fp;
 367         data.refname = NULL;
 368         data.refnames = refnames;
 369         data.msg_fmt = msg_fmt;
 370         for_each_rawref(warn_if_dangling_symref, &data);
 371 }
 372
 373 int refs_for_each_tag_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
 374 {
 375         return refs_for_each_ref_in(refs, "refs/tags/", fn, cb_data);
 376 }
 377
 378 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
 379 {
 380         return refs_for_each_tag_ref(get_main_ref_store(the_repository), fn, cb_data);
 381 }
 382
 383 int refs_for_each_branch_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
 384 {
 385         return refs_for_each_ref_in(refs, "refs/heads/", fn, cb_data);
 386 }
 387
 388 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
 389 {
 390         return refs_for_each_branch_ref(get_main_ref_store(the_repository), fn, cb_data);
 391 }
 392
 393 int refs_for_each_remote_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
 394 {
 395         return refs_for_each_ref_in(refs, "refs/remotes/", fn, cb_data);
 396 }
 397
 398 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
 399 {
 400         return refs_for_each_remote_ref(get_main_ref_store(the_repository), fn, cb_data);
 401 }
 402
 403 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
 404 {
 405         struct strbuf buf = STRBUF_INIT;
 406         int ret = 0;
 407         struct object_id oid;
 408         int flag;
 409
 410         strbuf_addf(&buf, "%sHEAD", get_git_namespace());
 411         if (!read_ref_full(buf.buf, RESOLVE_REF_READING, &oid, &flag))
 412                 ret = fn(buf.buf, &oid, flag, cb_data);
 413         strbuf_release(&buf);
 414
 415         return ret;
 416 }
 417
 418 void normalize_glob_ref(struct string_list_item *item, const char *prefix,
 419                         const char *pattern)
 420 {
 421         struct strbuf normalized_pattern = STRBUF_INIT;
 422
 423         if (*pattern == '/')
 424                 BUG("pattern must not start with '/'");
 425
 426         if (prefix) {
 427                 strbuf_addstr(&normalized_pattern, prefix);
 428         }
 429         else if (!starts_with(pattern, "refs/"))
 430                 strbuf_addstr(&normalized_pattern, "refs/");
 431         strbuf_addstr(&normalized_pattern, pattern);
 432         strbuf_strip_suffix(&normalized_pattern, "/");
 433
 434         item->string = strbuf_detach(&normalized_pattern, NULL);
 435         item->util = has_glob_specials(pattern) ? NULL : item->string;
 436         strbuf_release(&normalized_pattern);
 437 }
 438
 439 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
 440         const char *prefix, void *cb_data)
 441 {
 442         struct strbuf real_pattern = STRBUF_INIT;
 443         struct ref_filter filter;
 444         int ret;
 445
 446         if (!prefix && !starts_with(pattern, "refs/"))
 447                 strbuf_addstr(&real_pattern, "refs/");
 448         else if (prefix)
 449                 strbuf_addstr(&real_pattern, prefix);
 450         strbuf_addstr(&real_pattern, pattern);
 451
 452         if (!has_glob_specials(pattern)) {
 453                 /* Append implied '/' '*' if not present. */
 454                 strbuf_complete(&real_pattern, '/');
 455                 /* No need to check for '*', there is none. */
 456                 strbuf_addch(&real_pattern, '*');
 457         }
 458
 459         filter.pattern = real_pattern.buf;
 460         filter.fn = fn;
 461         filter.cb_data = cb_data;
 462         ret = for_each_ref(filter_refs, &filter);
 463
 464         strbuf_release(&real_pattern);
 465         return ret;
 466 }
 467
 468 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
 469 {
 470         return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
 471 }
 472
 473 const char *prettify_refname(const char *name)
 474 {
 475         if (skip_prefix(name, "refs/heads/", &name) ||
 476             skip_prefix(name, "refs/tags/", &name) ||
 477             skip_prefix(name, "refs/remotes/", &name))
 478                 ; /* nothing */
 479         return name;
 480 }
 481
 482 static const char *ref_rev_parse_rules[] = {
 483         "%.*s",
 484         "refs/%.*s",
 485         "refs/tags/%.*s",
 486         "refs/heads/%.*s",
 487         "refs/remotes/%.*s",
 488         "refs/remotes/%.*s/HEAD",
 489         NULL
 490 };
 491
 492 int refname_match(const char *abbrev_name, const char *full_name)
 493 {
 494         const char **p;
 495         const int abbrev_name_len = strlen(abbrev_name);
 496
 497         for (p = ref_rev_parse_rules; *p; p++) {
 498                 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
 499                         return 1;
 500                 }
 501         }
 502
 503         return 0;
 504 }
 505
 506 /*
 507  * *string and *len will only be substituted, and *string returned (for
 508  * later free()ing) if the string passed in is a magic short-hand form
 509  * to name a branch.
 510  */
 511 static char *substitute_branch_name(const char **string, int *len)
 512 {
 513         struct strbuf buf = STRBUF_INIT;
 514         int ret = interpret_branch_name(*string, *len, &buf, 0);
 515
 516         if (ret == *len) {
 517                 size_t size;
 518                 *string = strbuf_detach(&buf, &size);
 519                 *len = size;
 520                 return (char *)*string;
 521         }
 522
 523         return NULL;
 524 }
 525
 526 int dwim_ref(const char *str, int len, struct object_id *oid, char **ref)
 527 {
 528         char *last_branch = substitute_branch_name(&str, &len);
 529         int   refs_found  = expand_ref(str, len, oid, ref);
 530         free(last_branch);
 531         return refs_found;
 532 }
 533
 534 int expand_ref(const char *str, int len, struct object_id *oid, char **ref)
 535 {
 536         const char **p, *r;
 537         int refs_found = 0;
 538         struct strbuf fullref = STRBUF_INIT;
 539
 540         *ref = NULL;
 541         for (p = ref_rev_parse_rules; *p; p++) {
 542                 struct object_id oid_from_ref;
 543                 struct object_id *this_result;
 544                 int flag;
 545
 546                 this_result = refs_found ? &oid_from_ref : oid;
 547                 strbuf_reset(&fullref);
 548                 strbuf_addf(&fullref, *p, len, str);
 549                 r = resolve_ref_unsafe(fullref.buf, RESOLVE_REF_READING,
 550                                        this_result, &flag);
 551                 if (r) {
 552                         if (!refs_found++)
 553                                 *ref = xstrdup(r);
 554                         if (!warn_ambiguous_refs)
 555                                 break;
 556                 } else if ((flag & REF_ISSYMREF) && strcmp(fullref.buf, "HEAD")) {
 557                         warning("ignoring dangling symref %s.", fullref.buf);
 558                 } else if ((flag & REF_ISBROKEN) && strchr(fullref.buf, '/')) {
 559                         warning("ignoring broken ref %s.", fullref.buf);
 560                 }
 561         }
 562         strbuf_release(&fullref);
 563         return refs_found;
 564 }
 565
 566 int dwim_log(const char *str, int len, struct object_id *oid, char **log)
 567 {
 568         char *last_branch = substitute_branch_name(&str, &len);
 569         const char **p;
 570         int logs_found = 0;
 571         struct strbuf path = STRBUF_INIT;
 572
 573         *log = NULL;
 574         for (p = ref_rev_parse_rules; *p; p++) {
 575                 struct object_id hash;
 576                 const char *ref, *it;
 577
 578                 strbuf_reset(&path);
 579                 strbuf_addf(&path, *p, len, str);
 580                 ref = resolve_ref_unsafe(path.buf, RESOLVE_REF_READING,
 581                                          &hash, NULL);
 582                 if (!ref)
 583                         continue;
 584                 if (reflog_exists(path.buf))
 585                         it = path.buf;
 586                 else if (strcmp(ref, path.buf) && reflog_exists(ref))
 587                         it = ref;
 588                 else
 589                         continue;
 590                 if (!logs_found++) {
 591                         *log = xstrdup(it);
 592                         oidcpy(oid, &hash);
 593                 }
 594                 if (!warn_ambiguous_refs)
 595                         break;
 596         }
 597         strbuf_release(&path);
 598         free(last_branch);
 599         return logs_found;
 600 }
 601
 602 static int is_per_worktree_ref(const char *refname)
 603 {
 604         return !strcmp(refname, "HEAD") ||
 605                 starts_with(refname, "refs/bisect/");
 606 }
 607
 608 static int is_pseudoref_syntax(const char *refname)
 609 {
 610         const char *c;
 611
 612         for (c = refname; *c; c++) {
 613                 if (!isupper(*c) && *c != '-' && *c != '_')
 614                         return 0;
 615         }
 616
 617         return 1;
 618 }
 619
 620 enum ref_type ref_type(const char *refname)
 621 {
 622         if (is_per_worktree_ref(refname))
 623                 return REF_TYPE_PER_WORKTREE;
 624         if (is_pseudoref_syntax(refname))
 625                 return REF_TYPE_PSEUDOREF;
 626        return REF_TYPE_NORMAL;
 627 }
 628
 629 long get_files_ref_lock_timeout_ms(void)
 630 {
 631         static int configured = 0;
 632
 633         /* The default timeout is 100 ms: */
 634         static int timeout_ms = 100;
 635
 636         if (!configured) {
 637                 git_config_get_int("core.filesreflocktimeout", &timeout_ms);
 638                 configured = 1;
 639         }
 640
 641         return timeout_ms;
 642 }
 643
 644 static int write_pseudoref(const char *pseudoref, const struct object_id *oid,
 645                            const struct object_id *old_oid, struct strbuf *err)
 646 {
 647         const char *filename;
 648         int fd;
 649         static struct lock_file lock;
 650         struct strbuf buf = STRBUF_INIT;
 651         int ret = -1;
 652
 653         if (!oid)
 654                 return 0;
 655
 656         strbuf_addf(&buf, "%s\n", oid_to_hex(oid));
 657
 658         filename = git_path("%s", pseudoref);
 659         fd = hold_lock_file_for_update_timeout(&lock, filename,
 660                                                LOCK_DIE_ON_ERROR,
 661                                                get_files_ref_lock_timeout_ms());
 662         if (fd < 0) {
 663                 strbuf_addf(err, "could not open '%s' for writing: %s",
 664                             filename, strerror(errno));
 665                 goto done;
 666         }
 667
 668         if (old_oid) {
 669                 struct object_id actual_old_oid;
 670
 671                 if (read_ref(pseudoref, &actual_old_oid))
 672                         die("could not read ref '%s'", pseudoref);
 673                 if (oidcmp(&actual_old_oid, old_oid)) {
 674                         strbuf_addf(err, "unexpected sha1 when writing '%s'", pseudoref);
 675                         rollback_lock_file(&lock);
 676                         goto done;
 677                 }
 678         }
 679
 680         if (write_in_full(fd, buf.buf, buf.len) < 0) {
 681                 strbuf_addf(err, "could not write to '%s'", filename);
 682                 rollback_lock_file(&lock);
 683                 goto done;
 684         }
 685
 686         commit_lock_file(&lock);
 687         ret = 0;
 688 done:
 689         strbuf_release(&buf);
 690         return ret;
 691 }
 692
 693 static int delete_pseudoref(const char *pseudoref, const struct object_id *old_oid)
 694 {
 695         static struct lock_file lock;
 696         const char *filename;
 697
 698         filename = git_path("%s", pseudoref);
 699
 700         if (old_oid && !is_null_oid(old_oid)) {
 701                 int fd;
 702                 struct object_id actual_old_oid;
 703
 704                 fd = hold_lock_file_for_update_timeout(
 705                                 &lock, filename, LOCK_DIE_ON_ERROR,
 706                                 get_files_ref_lock_timeout_ms());
 707                 if (fd < 0)
 708                         die_errno(_("Could not open '%s' for writing"), filename);
 709                 if (read_ref(pseudoref, &actual_old_oid))
 710                         die("could not read ref '%s'", pseudoref);
 711                 if (oidcmp(&actual_old_oid, old_oid)) {
 712                         warning("Unexpected sha1 when deleting %s", pseudoref);
 713                         rollback_lock_file(&lock);
 714                         return -1;
 715                 }
 716
 717                 unlink(filename);
 718                 rollback_lock_file(&lock);
 719         } else {
 720                 unlink(filename);
 721         }
 722
 723         return 0;
 724 }
 725
 726 int refs_delete_ref(struct ref_store *refs, const char *msg,
 727                     const char *refname,
 728                     const struct object_id *old_oid,
 729                     unsigned int flags)
 730 {
 731         struct ref_transaction *transaction;
 732         struct strbuf err = STRBUF_INIT;
 733
 734         if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
 735                 assert(refs == get_main_ref_store(the_repository));
 736                 return delete_pseudoref(refname, old_oid);
 737         }
 738
 739         transaction = ref_store_transaction_begin(refs, &err);
 740         if (!transaction ||
 741             ref_transaction_delete(transaction, refname, old_oid,
 742                                    flags, msg, &err) ||
 743             ref_transaction_commit(transaction, &err)) {
 744                 error("%s", err.buf);
 745                 ref_transaction_free(transaction);
 746                 strbuf_release(&err);
 747                 return 1;
 748         }
 749         ref_transaction_free(transaction);
 750         strbuf_release(&err);
 751         return 0;
 752 }
 753
 754 int delete_ref(const char *msg, const char *refname,
 755                const struct object_id *old_oid, unsigned int flags)
 756 {
 757         return refs_delete_ref(get_main_ref_store(the_repository), msg, refname,
 758                                old_oid, flags);
 759 }
 760
 761 int copy_reflog_msg(char *buf, const char *msg)
 762 {
 763         char *cp = buf;
 764         char c;
 765         int wasspace = 1;
 766
 767         *cp++ = '\t';
 768         while ((c = *msg++)) {
 769                 if (wasspace && isspace(c))
 770                         continue;
 771                 wasspace = isspace(c);
 772                 if (wasspace)
 773                         c = ' ';
 774                 *cp++ = c;
 775         }
 776         while (buf < cp && isspace(cp[-1]))
 777                 cp--;
 778         *cp++ = '\n';
 779         return cp - buf;
 780 }
 781
 782 int should_autocreate_reflog(const char *refname)
 783 {
 784         switch (log_all_ref_updates) {
 785         case LOG_REFS_ALWAYS:
 786                 return 1;
 787         case LOG_REFS_NORMAL:
 788                 return starts_with(refname, "refs/heads/") ||
 789                         starts_with(refname, "refs/remotes/") ||
 790                         starts_with(refname, "refs/notes/") ||
 791                         !strcmp(refname, "HEAD");
 792         default:
 793                 return 0;
 794         }
 795 }
 796
 797 int is_branch(const char *refname)
 798 {
 799         return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
 800 }
 801
 802 struct read_ref_at_cb {
 803         const char *refname;
 804         timestamp_t at_time;
 805         int cnt;
 806         int reccnt;
 807         struct object_id *oid;
 808         int found_it;
 809
 810         struct object_id ooid;
 811         struct object_id noid;
 812         int tz;
 813         timestamp_t date;
 814         char **msg;
 815         timestamp_t *cutoff_time;
 816         int *cutoff_tz;
 817         int *cutoff_cnt;
 818 };
 819
 820 static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
 821                 const char *email, timestamp_t timestamp, int tz,
 822                 const char *message, void *cb_data)
 823 {
 824         struct read_ref_at_cb *cb = cb_data;
 825
 826         cb->reccnt++;
 827         cb->tz = tz;
 828         cb->date = timestamp;
 829
 830         if (timestamp <= cb->at_time || cb->cnt == 0) {
 831                 if (cb->msg)
 832                         *cb->msg = xstrdup(message);
 833                 if (cb->cutoff_time)
 834                         *cb->cutoff_time = timestamp;
 835                 if (cb->cutoff_tz)
 836                         *cb->cutoff_tz = tz;
 837                 if (cb->cutoff_cnt)
 838                         *cb->cutoff_cnt = cb->reccnt - 1;
 839                 /*
 840                  * we have not yet updated cb->[n|o]oid so they still
 841                  * hold the values for the previous record.
 842                  */
 843                 if (!is_null_oid(&cb->ooid)) {
 844                         oidcpy(cb->oid, noid);
 845                         if (oidcmp(&cb->ooid, noid))
 846                                 warning("Log for ref %s has gap after %s.",
 847                                         cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
 848                 }
 849                 else if (cb->date == cb->at_time)
 850                         oidcpy(cb->oid, noid);
 851                 else if (oidcmp(noid, cb->oid))
 852                         warning("Log for ref %s unexpectedly ended on %s.",
 853                                 cb->refname, show_date(cb->date, cb->tz,
 854                                                        DATE_MODE(RFC2822)));
 855                 oidcpy(&cb->ooid, ooid);
 856                 oidcpy(&cb->noid, noid);
 857                 cb->found_it = 1;
 858                 return 1;
 859         }
 860         oidcpy(&cb->ooid, ooid);
 861         oidcpy(&cb->noid, noid);
 862         if (cb->cnt > 0)
 863                 cb->cnt--;
 864         return 0;
 865 }
 866
 867 static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
 868                                   const char *email, timestamp_t timestamp,
 869                                   int tz, const char *message, void *cb_data)
 870 {
 871         struct read_ref_at_cb *cb = cb_data;
 872
 873         if (cb->msg)
 874                 *cb->msg = xstrdup(message);
 875         if (cb->cutoff_time)
 876                 *cb->cutoff_time = timestamp;
 877         if (cb->cutoff_tz)
 878                 *cb->cutoff_tz = tz;
 879         if (cb->cutoff_cnt)
 880                 *cb->cutoff_cnt = cb->reccnt;
 881         oidcpy(cb->oid, ooid);
 882         if (is_null_oid(cb->oid))
 883                 oidcpy(cb->oid, noid);
 884         /* We just want the first entry */
 885         return 1;
 886 }
 887
 888 int read_ref_at(const char *refname, unsigned int flags, timestamp_t at_time, int cnt,
 889                 struct object_id *oid, char **msg,
 890                 timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
 891 {
 892         struct read_ref_at_cb cb;
 893
 894         memset(&cb, 0, sizeof(cb));
 895         cb.refname = refname;
 896         cb.at_time = at_time;
 897         cb.cnt = cnt;
 898         cb.msg = msg;
 899         cb.cutoff_time = cutoff_time;
 900         cb.cutoff_tz = cutoff_tz;
 901         cb.cutoff_cnt = cutoff_cnt;
 902         cb.oid = oid;
 903
 904         for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
 905
 906         if (!cb.reccnt) {
 907                 if (flags & GET_OID_QUIETLY)
 908                         exit(128);
 909                 else
 910                         die("Log for %s is empty.", refname);
 911         }
 912         if (cb.found_it)
 913                 return 0;
 914
 915         for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
 916
 917         return 1;
 918 }
 919
 920 struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs,
 921                                                     struct strbuf *err)
 922 {
 923         struct ref_transaction *tr;
 924         assert(err);
 925
 926         tr = xcalloc(1, sizeof(struct ref_transaction));
 927         tr->ref_store = refs;
 928         return tr;
 929 }
 930
 931 struct ref_transaction *ref_transaction_begin(struct strbuf *err)
 932 {
 933         return ref_store_transaction_begin(get_main_ref_store(the_repository), err);
 934 }
 935
 936 void ref_transaction_free(struct ref_transaction *transaction)
 937 {
 938         size_t i;
 939
 940         if (!transaction)
 941                 return;
 942
 943         switch (transaction->state) {
 944         case REF_TRANSACTION_OPEN:
 945         case REF_TRANSACTION_CLOSED:
 946                 /* OK */
 947                 break;
 948         case REF_TRANSACTION_PREPARED:
 949                 die("BUG: free called on a prepared reference transaction");
 950                 break;
 951         default:
 952                 die("BUG: unexpected reference transaction state");
 953                 break;
 954         }
 955
 956         for (i = 0; i < transaction->nr; i++) {
 957                 free(transaction->updates[i]->msg);
 958                 free(transaction->updates[i]);
 959         }
 960         free(transaction->updates);
 961         free(transaction);
 962 }
 963
 964 struct ref_update *ref_transaction_add_update(
 965                 struct ref_transaction *transaction,
 966                 const char *refname, unsigned int flags,
 967                 const struct object_id *new_oid,
 968                 const struct object_id *old_oid,
 969                 const char *msg)
 970 {
 971         struct ref_update *update;
 972
 973         if (transaction->state != REF_TRANSACTION_OPEN)
 974                 die("BUG: update called for transaction that is not open");
 975
 976         FLEX_ALLOC_STR(update, refname, refname);
 977         ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
 978         transaction->updates[transaction->nr++] = update;
 979
 980         update->flags = flags;
 981
 982         if (flags & REF_HAVE_NEW)
 983                 oidcpy(&update->new_oid, new_oid);
 984         if (flags & REF_HAVE_OLD)
 985                 oidcpy(&update->old_oid, old_oid);
 986         update->msg = xstrdup_or_null(msg);
 987         return update;
 988 }
 989
 990 int ref_transaction_update(struct ref_transaction *transaction,
 991                            const char *refname,
 992                            const struct object_id *new_oid,
 993                            const struct object_id *old_oid,
 994                            unsigned int flags, const char *msg,
 995                            struct strbuf *err)
 996 {
 997         assert(err);
 998
 999         if ((new_oid && !is_null_oid(new_oid)) ?
1000             check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
1001             !refname_is_safe(refname)) {
1002                 strbuf_addf(err, "refusing to update ref with bad name '%s'",
1003                             refname);
1004                 return -1;
1005         }
1006
1007         if (flags & ~REF_TRANSACTION_UPDATE_ALLOWED_FLAGS)
1008                 BUG("illegal flags 0x%x passed to ref_transaction_update()", flags);
1009
1010         flags |= (new_oid ? REF_HAVE_NEW : 0) | (old_oid ? REF_HAVE_OLD : 0);
1011
1012         ref_transaction_add_update(transaction, refname, flags,
1013                                    new_oid, old_oid, msg);
1014         return 0;
1015 }
1016
1017 int ref_transaction_create(struct ref_transaction *transaction,
1018                            const char *refname,
1019                            const struct object_id *new_oid,
1020                            unsigned int flags, const char *msg,
1021                            struct strbuf *err)
1022 {
1023         if (!new_oid || is_null_oid(new_oid))
1024                 die("BUG: create called without valid new_oid");
1025         return ref_transaction_update(transaction, refname, new_oid,
1026                                       &null_oid, flags, msg, err);
1027 }
1028
1029 int ref_transaction_delete(struct ref_transaction *transaction,
1030                            const char *refname,
1031                            const struct object_id *old_oid,
1032                            unsigned int flags, const char *msg,
1033                            struct strbuf *err)
1034 {
1035         if (old_oid && is_null_oid(old_oid))
1036                 die("BUG: delete called with old_oid set to zeros");
1037         return ref_transaction_update(transaction, refname,
1038                                       &null_oid, old_oid,
1039                                       flags, msg, err);
1040 }
1041
1042 int ref_transaction_verify(struct ref_transaction *transaction,
1043                            const char *refname,
1044                            const struct object_id *old_oid,
1045                            unsigned int flags,
1046                            struct strbuf *err)
1047 {
1048         if (!old_oid)
1049                 die("BUG: verify called with old_oid set to NULL");
1050         return ref_transaction_update(transaction, refname,
1051                                       NULL, old_oid,
1052                                       flags, NULL, err);
1053 }
1054
1055 int refs_update_ref(struct ref_store *refs, const char *msg,
1056                     const char *refname, const struct object_id *new_oid,
1057                     const struct object_id *old_oid, unsigned int flags,
1058                     enum action_on_err onerr)
1059 {
1060         struct ref_transaction *t = NULL;
1061         struct strbuf err = STRBUF_INIT;
1062         int ret = 0;
1063
1064         if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
1065                 assert(refs == get_main_ref_store(the_repository));
1066                 ret = write_pseudoref(refname, new_oid, old_oid, &err);
1067         } else {
1068                 t = ref_store_transaction_begin(refs, &err);
1069                 if (!t ||
1070                     ref_transaction_update(t, refname, new_oid, old_oid,
1071                                            flags, msg, &err) ||
1072                     ref_transaction_commit(t, &err)) {
1073                         ret = 1;
1074                         ref_transaction_free(t);
1075                 }
1076         }
1077         if (ret) {
1078                 const char *str = "update_ref failed for ref '%s': %s";
1079
1080                 switch (onerr) {
1081                 case UPDATE_REFS_MSG_ON_ERR:
1082                         error(str, refname, err.buf);
1083                         break;
1084                 case UPDATE_REFS_DIE_ON_ERR:
1085                         die(str, refname, err.buf);
1086                         break;
1087                 case UPDATE_REFS_QUIET_ON_ERR:
1088                         break;
1089                 }
1090                 strbuf_release(&err);
1091                 return 1;
1092         }
1093         strbuf_release(&err);
1094         if (t)
1095                 ref_transaction_free(t);
1096         return 0;
1097 }
1098
1099 int update_ref(const char *msg, const char *refname,
1100                const struct object_id *new_oid,
1101                const struct object_id *old_oid,
1102                unsigned int flags, enum action_on_err onerr)
1103 {
1104         return refs_update_ref(get_main_ref_store(the_repository), msg, refname, new_oid,
1105                                old_oid, flags, onerr);
1106 }
1107
1108 char *shorten_unambiguous_ref(const char *refname, int strict)
1109 {
1110         int i;
1111         static char **scanf_fmts;
1112         static int nr_rules;
1113         char *short_name;
1114         struct strbuf resolved_buf = STRBUF_INIT;
1115
1116         if (!nr_rules) {
1117                 /*
1118                  * Pre-generate scanf formats from ref_rev_parse_rules[].
1119                  * Generate a format suitable for scanf from a
1120                  * ref_rev_parse_rules rule by interpolating "%s" at the
1121                  * location of the "%.*s".
1122                  */
1123                 size_t total_len = 0;
1124                 size_t offset = 0;
1125
1126                 /* the rule list is NULL terminated, count them first */
1127                 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
1128                         /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
1129                         total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
1130
1131                 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
1132
1133                 offset = 0;
1134                 for (i = 0; i < nr_rules; i++) {
1135                         assert(offset < total_len);
1136                         scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
1137                         offset += snprintf(scanf_fmts[i], total_len - offset,
1138                                            ref_rev_parse_rules[i], 2, "%s") + 1;
1139                 }
1140         }
1141
1142         /* bail out if there are no rules */
1143         if (!nr_rules)
1144                 return xstrdup(refname);
1145
1146         /* buffer for scanf result, at most refname must fit */
1147         short_name = xstrdup(refname);
1148
1149         /* skip first rule, it will always match */
1150         for (i = nr_rules - 1; i > 0 ; --i) {
1151                 int j;
1152                 int rules_to_fail = i;
1153                 int short_name_len;
1154
1155                 if (1 != sscanf(refname, scanf_fmts[i], short_name))
1156                         continue;
1157
1158                 short_name_len = strlen(short_name);
1159
1160                 /*
1161                  * in strict mode, all (except the matched one) rules
1162                  * must fail to resolve to a valid non-ambiguous ref
1163                  */
1164                 if (strict)
1165                         rules_to_fail = nr_rules;
1166
1167                 /*
1168                  * check if the short name resolves to a valid ref,
1169                  * but use only rules prior to the matched one
1170                  */
1171                 for (j = 0; j < rules_to_fail; j++) {
1172                         const char *rule = ref_rev_parse_rules[j];
1173
1174                         /* skip matched rule */
1175                         if (i == j)
1176                                 continue;
1177
1178                         /*
1179                          * the short name is ambiguous, if it resolves
1180                          * (with this previous rule) to a valid ref
1181                          * read_ref() returns 0 on success
1182                          */
1183                         strbuf_reset(&resolved_buf);
1184                         strbuf_addf(&resolved_buf, rule,
1185                                     short_name_len, short_name);
1186                         if (ref_exists(resolved_buf.buf))
1187                                 break;
1188                 }
1189
1190                 /*
1191                  * short name is non-ambiguous if all previous rules
1192                  * haven't resolved to a valid ref
1193                  */
1194                 if (j == rules_to_fail) {
1195                         strbuf_release(&resolved_buf);
1196                         return short_name;
1197                 }
1198         }
1199
1200         strbuf_release(&resolved_buf);
1201         free(short_name);
1202         return xstrdup(refname);
1203 }
1204
1205 static struct string_list *hide_refs;
1206
1207 int parse_hide_refs_config(const char *var, const char *value, const char *section)
1208 {
1209         const char *key;
1210         if (!strcmp("transfer.hiderefs", var) ||
1211             (!parse_config_key(var, section, NULL, NULL, &key) &&
1212              !strcmp(key, "hiderefs"))) {
1213                 char *ref;
1214                 int len;
1215
1216                 if (!value)
1217                         return config_error_nonbool(var);
1218                 ref = xstrdup(value);
1219                 len = strlen(ref);
1220                 while (len && ref[len - 1] == '/')
1221                         ref[--len] = '\0';
1222                 if (!hide_refs) {
1223                         hide_refs = xcalloc(1, sizeof(*hide_refs));
1224                         hide_refs->strdup_strings = 1;
1225                 }
1226                 string_list_append(hide_refs, ref);
1227         }
1228         return 0;
1229 }
1230
1231 int ref_is_hidden(const char *refname, const char *refname_full)
1232 {
1233         int i;
1234
1235         if (!hide_refs)
1236                 return 0;
1237         for (i = hide_refs->nr - 1; i >= 0; i--) {
1238                 const char *match = hide_refs->items[i].string;
1239                 const char *subject;
1240                 int neg = 0;
1241                 const char *p;
1242
1243                 if (*match == '!') {
1244                         neg = 1;
1245                         match++;
1246                 }
1247
1248                 if (*match == '^') {
1249                         subject = refname_full;
1250                         match++;
1251                 } else {
1252                         subject = refname;
1253                 }
1254
1255                 /* refname can be NULL when namespaces are used. */
1256                 if (subject &&
1257                     skip_prefix(subject, match, &p) &&
1258                     (!*p || *p == '/'))
1259                         return !neg;
1260         }
1261         return 0;
1262 }
1263
1264 const char *find_descendant_ref(const char *dirname,
1265                                 const struct string_list *extras,
1266                                 const struct string_list *skip)
1267 {
1268         int pos;
1269
1270         if (!extras)
1271                 return NULL;
1272
1273         /*
1274          * Look at the place where dirname would be inserted into
1275          * extras. If there is an entry at that position that starts
1276          * with dirname (remember, dirname includes the trailing
1277          * slash) and is not in skip, then we have a conflict.
1278          */
1279         for (pos = string_list_find_insert_index(extras, dirname, 0);
1280              pos < extras->nr; pos++) {
1281                 const char *extra_refname = extras->items[pos].string;
1282
1283                 if (!starts_with(extra_refname, dirname))
1284                         break;
1285
1286                 if (!skip || !string_list_has_string(skip, extra_refname))
1287                         return extra_refname;
1288         }
1289         return NULL;
1290 }
1291
1292 int refs_rename_ref_available(struct ref_store *refs,
1293                               const char *old_refname,
1294                               const char *new_refname)
1295 {
1296         struct string_list skip = STRING_LIST_INIT_NODUP;
1297         struct strbuf err = STRBUF_INIT;
1298         int ok;
1299
1300         string_list_insert(&skip, old_refname);
1301         ok = !refs_verify_refname_available(refs, new_refname,
1302                                             NULL, &skip, &err);
1303         if (!ok)
1304                 error("%s", err.buf);
1305
1306         string_list_clear(&skip, 0);
1307         strbuf_release(&err);
1308         return ok;
1309 }
1310
1311 int refs_head_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1312 {
1313         struct object_id oid;
1314         int flag;
1315
1316         if (!refs_read_ref_full(refs, "HEAD", RESOLVE_REF_READING,
1317                                 &oid, &flag))
1318                 return fn("HEAD", &oid, flag, cb_data);
1319
1320         return 0;
1321 }
1322
1323 int head_ref(each_ref_fn fn, void *cb_data)
1324 {
1325         return refs_head_ref(get_main_ref_store(the_repository), fn, cb_data);
1326 }
1327
1328 struct ref_iterator *refs_ref_iterator_begin(
1329                 struct ref_store *refs,
1330                 const char *prefix, int trim, int flags)
1331 {
1332         struct ref_iterator *iter;
1333
1334         if (ref_paranoia < 0)
1335                 ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
1336         if (ref_paranoia)
1337                 flags |= DO_FOR_EACH_INCLUDE_BROKEN;
1338
1339         iter = refs->be->iterator_begin(refs, prefix, flags);
1340
1341         /*
1342          * `iterator_begin()` already takes care of prefix, but we
1343          * might need to do some trimming:
1344          */
1345         if (trim)
1346                 iter = prefix_ref_iterator_begin(iter, "", trim);
1347
1348         /* Sanity check for subclasses: */
1349         if (!iter->ordered)
1350                 BUG("reference iterator is not ordered");
1351
1352         return iter;
1353 }
1354
1355 /*
1356  * Call fn for each reference in the specified submodule for which the
1357  * refname begins with prefix. If trim is non-zero, then trim that
1358  * many characters off the beginning of each refname before passing
1359  * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1360  * include broken references in the iteration. If fn ever returns a
1361  * non-zero value, stop the iteration and return that value;
1362  * otherwise, return 0.
1363  */
1364 static int do_for_each_ref(struct ref_store *refs, const char *prefix,
1365                            each_ref_fn fn, int trim, int flags, void *cb_data)
1366 {
1367         struct ref_iterator *iter;
1368
1369         if (!refs)
1370                 return 0;
1371
1372         iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1373
1374         return do_for_each_ref_iterator(iter, fn, cb_data);
1375 }
1376
1377 int refs_for_each_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1378 {
1379         return do_for_each_ref(refs, "", fn, 0, 0, cb_data);
1380 }
1381
1382 int for_each_ref(each_ref_fn fn, void *cb_data)
1383 {
1384         return refs_for_each_ref(get_main_ref_store(the_repository), fn, cb_data);
1385 }
1386
1387 int refs_for_each_ref_in(struct ref_store *refs, const char *prefix,
1388                          each_ref_fn fn, void *cb_data)
1389 {
1390         return do_for_each_ref(refs, prefix, fn, strlen(prefix), 0, cb_data);
1391 }
1392
1393 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1394 {
1395         return refs_for_each_ref_in(get_main_ref_store(the_repository), prefix, fn, cb_data);
1396 }
1397
1398 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1399 {
1400         unsigned int flag = 0;
1401
1402         if (broken)
1403                 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1404         return do_for_each_ref(get_main_ref_store(the_repository),
1405                                prefix, fn, 0, flag, cb_data);
1406 }
1407
1408 int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix,
1409                              each_ref_fn fn, void *cb_data,
1410                              unsigned int broken)
1411 {
1412         unsigned int flag = 0;
1413
1414         if (broken)
1415                 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1416         return do_for_each_ref(refs, prefix, fn, 0, flag, cb_data);
1417 }
1418
1419 int for_each_replace_ref(struct repository *r, each_ref_fn fn, void *cb_data)
1420 {
1421         return do_for_each_ref(get_main_ref_store(r),
1422                                git_replace_ref_base, fn,
1423                                strlen(git_replace_ref_base),
1424                                DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1425 }
1426
1427 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1428 {
1429         struct strbuf buf = STRBUF_INIT;
1430         int ret;
1431         strbuf_addf(&buf, "%srefs/", get_git_namespace());
1432         ret = do_for_each_ref(get_main_ref_store(the_repository),
1433                               buf.buf, fn, 0, 0, cb_data);
1434         strbuf_release(&buf);
1435         return ret;
1436 }
1437
1438 int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1439 {
1440         return do_for_each_ref(refs, "", fn, 0,
1441                                DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1442 }
1443
1444 int for_each_rawref(each_ref_fn fn, void *cb_data)
1445 {
1446         return refs_for_each_rawref(get_main_ref_store(the_repository), fn, cb_data);
1447 }
1448
1449 int refs_read_raw_ref(struct ref_store *ref_store,
1450                       const char *refname, struct object_id *oid,
1451                       struct strbuf *referent, unsigned int *type)
1452 {
1453         return ref_store->be->read_raw_ref(ref_store, refname, oid, referent, type);
1454 }
1455
1456 /* This function needs to return a meaningful errno on failure */
1457 const char *refs_resolve_ref_unsafe(struct ref_store *refs,
1458                                     const char *refname,
1459                                     int resolve_flags,
1460                                     struct object_id *oid, int *flags)
1461 {
1462         static struct strbuf sb_refname = STRBUF_INIT;
1463         struct object_id unused_oid;
1464         int unused_flags;
1465         int symref_count;
1466
1467         if (!oid)
1468                 oid = &unused_oid;
1469         if (!flags)
1470                 flags = &unused_flags;
1471
1472         *flags = 0;
1473
1474         if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1475                 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1476                     !refname_is_safe(refname)) {
1477                         errno = EINVAL;
1478                         return NULL;
1479                 }
1480
1481                 /*
1482                  * dwim_ref() uses REF_ISBROKEN to distinguish between
1483                  * missing refs and refs that were present but invalid,
1484                  * to complain about the latter to stderr.
1485                  *
1486                  * We don't know whether the ref exists, so don't set
1487                  * REF_ISBROKEN yet.
1488                  */
1489                 *flags |= REF_BAD_NAME;
1490         }
1491
1492         for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1493                 unsigned int read_flags = 0;
1494
1495                 if (refs_read_raw_ref(refs, refname,
1496                                       oid, &sb_refname, &read_flags)) {
1497                         *flags |= read_flags;
1498
1499                         /* In reading mode, refs must eventually resolve */
1500                         if (resolve_flags & RESOLVE_REF_READING)
1501                                 return NULL;
1502
1503                         /*
1504                          * Otherwise a missing ref is OK. But the files backend
1505                          * may show errors besides ENOENT if there are
1506                          * similarly-named refs.
1507                          */
1508                         if (errno != ENOENT &&
1509                             errno != EISDIR &&
1510                             errno != ENOTDIR)
1511                                 return NULL;
1512
1513                         oidclr(oid);
1514                         if (*flags & REF_BAD_NAME)
1515                                 *flags |= REF_ISBROKEN;
1516                         return refname;
1517                 }
1518
1519                 *flags |= read_flags;
1520
1521                 if (!(read_flags & REF_ISSYMREF)) {
1522                         if (*flags & REF_BAD_NAME) {
1523                                 oidclr(oid);
1524                                 *flags |= REF_ISBROKEN;
1525                         }
1526                         return refname;
1527                 }
1528
1529                 refname = sb_refname.buf;
1530                 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1531                         oidclr(oid);
1532                         return refname;
1533                 }
1534                 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1535                         if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1536                             !refname_is_safe(refname)) {
1537                                 errno = EINVAL;
1538                                 return NULL;
1539                         }
1540
1541                         *flags |= REF_ISBROKEN | REF_BAD_NAME;
1542                 }
1543         }
1544
1545         errno = ELOOP;
1546         return NULL;
1547 }
1548
1549 /* backend functions */
1550 int refs_init_db(struct strbuf *err)
1551 {
1552         struct ref_store *refs = get_main_ref_store(the_repository);
1553
1554         return refs->be->init_db(refs, err);
1555 }
1556
1557 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1558                                struct object_id *oid, int *flags)
1559 {
1560         return refs_resolve_ref_unsafe(get_main_ref_store(the_repository), refname,
1561                                        resolve_flags, oid, flags);
1562 }
1563
1564 int resolve_gitlink_ref(const char *submodule, const char *refname,
1565                         struct object_id *oid)
1566 {
1567         struct ref_store *refs;
1568         int flags;
1569
1570         refs = get_submodule_ref_store(submodule);
1571
1572         if (!refs)
1573                 return -1;
1574
1575         if (!refs_resolve_ref_unsafe(refs, refname, 0, oid, &flags) ||
1576             is_null_oid(oid))
1577                 return -1;
1578         return 0;
1579 }
1580
1581 struct ref_store_hash_entry
1582 {
1583         struct hashmap_entry ent; /* must be the first member! */
1584
1585         struct ref_store *refs;
1586
1587         /* NUL-terminated identifier of the ref store: */
1588         char name[FLEX_ARRAY];
1589 };
1590
1591 static int ref_store_hash_cmp(const void *unused_cmp_data,
1592                               const void *entry, const void *entry_or_key,
1593                               const void *keydata)
1594 {
1595         const struct ref_store_hash_entry *e1 = entry, *e2 = entry_or_key;
1596         const char *name = keydata ? keydata : e2->name;
1597
1598         return strcmp(e1->name, name);
1599 }
1600
1601 static struct ref_store_hash_entry *alloc_ref_store_hash_entry(
1602                 const char *name, struct ref_store *refs)
1603 {
1604         struct ref_store_hash_entry *entry;
1605
1606         FLEX_ALLOC_STR(entry, name, name);
1607         hashmap_entry_init(entry, strhash(name));
1608         entry->refs = refs;
1609         return entry;
1610 }
1611
1612 /* A hashmap of ref_stores, stored by submodule name: */
1613 static struct hashmap submodule_ref_stores;
1614
1615 /* A hashmap of ref_stores, stored by worktree id: */
1616 static struct hashmap worktree_ref_stores;
1617
1618 /*
1619  * Look up a ref store by name. If that ref_store hasn't been
1620  * registered yet, return NULL.
1621  */
1622 static struct ref_store *lookup_ref_store_map(struct hashmap *map,
1623                                               const char *name)
1624 {
1625         struct ref_store_hash_entry *entry;
1626
1627         if (!map->tablesize)
1628                 /* It's initialized on demand in register_ref_store(). */
1629                 return NULL;
1630
1631         entry = hashmap_get_from_hash(map, strhash(name), name);
1632         return entry ? entry->refs : NULL;
1633 }
1634
1635 /*
1636  * Create, record, and return a ref_store instance for the specified
1637  * gitdir.
1638  */
1639 static struct ref_store *ref_store_init(const char *gitdir,
1640                                         unsigned int flags)
1641 {
1642         const char *be_name = "files";
1643         struct ref_storage_be *be = find_ref_storage_backend(be_name);
1644         struct ref_store *refs;
1645
1646         if (!be)
1647                 die("BUG: reference backend %s is unknown", be_name);
1648
1649         refs = be->init(gitdir, flags);
1650         return refs;
1651 }
1652
1653 struct ref_store *get_main_ref_store(struct repository *r)
1654 {
1655         if (r->refs)
1656                 return r->refs;
1657
1658         r->refs = ref_store_init(r->gitdir, REF_STORE_ALL_CAPS);
1659         return r->refs;
1660 }
1661
1662 /*
1663  * Associate a ref store with a name. It is a fatal error to call this
1664  * function twice for the same name.
1665  */
1666 static void register_ref_store_map(struct hashmap *map,
1667                                    const char *type,
1668                                    struct ref_store *refs,
1669                                    const char *name)
1670 {
1671         if (!map->tablesize)
1672                 hashmap_init(map, ref_store_hash_cmp, NULL, 0);
1673
1674         if (hashmap_put(map, alloc_ref_store_hash_entry(name, refs)))
1675                 die("BUG: %s ref_store '%s' initialized twice", type, name);
1676 }
1677
1678 struct ref_store *get_submodule_ref_store(const char *submodule)
1679 {
1680         struct strbuf submodule_sb = STRBUF_INIT;
1681         struct ref_store *refs;
1682         char *to_free = NULL;
1683         size_t len;
1684
1685         if (!submodule)
1686                 return NULL;
1687
1688         len = strlen(submodule);
1689         while (len && is_dir_sep(submodule[len - 1]))
1690                 len--;
1691         if (!len)
1692                 return NULL;
1693
1694         if (submodule[len])
1695                 /* We need to strip off one or more trailing slashes */
1696                 submodule = to_free = xmemdupz(submodule, len);
1697
1698         refs = lookup_ref_store_map(&submodule_ref_stores, submodule);
1699         if (refs)
1700                 goto done;
1701
1702         strbuf_addstr(&submodule_sb, submodule);
1703         if (!is_nonbare_repository_dir(&submodule_sb))
1704                 goto done;
1705
1706         if (submodule_to_gitdir(&submodule_sb, submodule))
1707                 goto done;
1708
1709         /* assume that add_submodule_odb() has been called */
1710         refs = ref_store_init(submodule_sb.buf,
1711                               REF_STORE_READ | REF_STORE_ODB);
1712         register_ref_store_map(&submodule_ref_stores, "submodule",
1713                                refs, submodule);
1714
1715 done:
1716         strbuf_release(&submodule_sb);
1717         free(to_free);
1718
1719         return refs;
1720 }
1721
1722 struct ref_store *get_worktree_ref_store(const struct worktree *wt)
1723 {
1724         struct ref_store *refs;
1725         const char *id;
1726
1727         if (wt->is_current)
1728                 return get_main_ref_store(the_repository);
1729
1730         id = wt->id ? wt->id : "/";
1731         refs = lookup_ref_store_map(&worktree_ref_stores, id);
1732         if (refs)
1733                 return refs;
1734
1735         if (wt->id)
1736                 refs = ref_store_init(git_common_path("worktrees/%s", wt->id),
1737                                       REF_STORE_ALL_CAPS);
1738         else
1739                 refs = ref_store_init(get_git_common_dir(),
1740                                       REF_STORE_ALL_CAPS);
1741
1742         if (refs)
1743                 register_ref_store_map(&worktree_ref_stores, "worktree",
1744                                        refs, id);
1745         return refs;
1746 }
1747
1748 void base_ref_store_init(struct ref_store *refs,
1749                          const struct ref_storage_be *be)
1750 {
1751         refs->be = be;
1752 }
1753
1754 /* backend functions */
1755 int refs_pack_refs(struct ref_store *refs, unsigned int flags)
1756 {
1757         return refs->be->pack_refs(refs, flags);
1758 }
1759
1760 int refs_peel_ref(struct ref_store *refs, const char *refname,
1761                   struct object_id *oid)
1762 {
1763         int flag;
1764         struct object_id base;
1765
1766         if (current_ref_iter && current_ref_iter->refname == refname) {
1767                 struct object_id peeled;
1768
1769                 if (ref_iterator_peel(current_ref_iter, &peeled))
1770                         return -1;
1771                 oidcpy(oid, &peeled);
1772                 return 0;
1773         }
1774
1775         if (refs_read_ref_full(refs, refname,
1776                                RESOLVE_REF_READING, &base, &flag))
1777                 return -1;
1778
1779         return peel_object(&base, oid);
1780 }
1781
1782 int peel_ref(const char *refname, struct object_id *oid)
1783 {
1784         return refs_peel_ref(get_main_ref_store(the_repository), refname, oid);
1785 }
1786
1787 int refs_create_symref(struct ref_store *refs,
1788                        const char *ref_target,
1789                        const char *refs_heads_master,
1790                        const char *logmsg)
1791 {
1792         return refs->be->create_symref(refs, ref_target,
1793                                        refs_heads_master,
1794                                        logmsg);
1795 }
1796
1797 int create_symref(const char *ref_target, const char *refs_heads_master,
1798                   const char *logmsg)
1799 {
1800         return refs_create_symref(get_main_ref_store(the_repository), ref_target,
1801                                   refs_heads_master, logmsg);
1802 }
1803
1804 int ref_update_reject_duplicates(struct string_list *refnames,
1805                                  struct strbuf *err)
1806 {
1807         size_t i, n = refnames->nr;
1808
1809         assert(err);
1810
1811         for (i = 1; i < n; i++) {
1812                 int cmp = strcmp(refnames->items[i - 1].string,
1813                                  refnames->items[i].string);
1814
1815                 if (!cmp) {
1816                         strbuf_addf(err,
1817                                     "multiple updates for ref '%s' not allowed.",
1818                                     refnames->items[i].string);
1819                         return 1;
1820                 } else if (cmp > 0) {
1821                         die("BUG: ref_update_reject_duplicates() received unsorted list");
1822                 }
1823         }
1824         return 0;
1825 }
1826
1827 int ref_transaction_prepare(struct ref_transaction *transaction,
1828                             struct strbuf *err)
1829 {
1830         struct ref_store *refs = transaction->ref_store;
1831
1832         switch (transaction->state) {
1833         case REF_TRANSACTION_OPEN:
1834                 /* Good. */
1835                 break;
1836         case REF_TRANSACTION_PREPARED:
1837                 die("BUG: prepare called twice on reference transaction");
1838                 break;
1839         case REF_TRANSACTION_CLOSED:
1840                 die("BUG: prepare called on a closed reference transaction");
1841                 break;
1842         default:
1843                 die("BUG: unexpected reference transaction state");
1844                 break;
1845         }
1846
1847         if (getenv(GIT_QUARANTINE_ENVIRONMENT)) {
1848                 strbuf_addstr(err,
1849                               _("ref updates forbidden inside quarantine environment"));
1850                 return -1;
1851         }
1852
1853         return refs->be->transaction_prepare(refs, transaction, err);
1854 }
1855
1856 int ref_transaction_abort(struct ref_transaction *transaction,
1857                           struct strbuf *err)
1858 {
1859         struct ref_store *refs = transaction->ref_store;
1860         int ret = 0;
1861
1862         switch (transaction->state) {
1863         case REF_TRANSACTION_OPEN:
1864                 /* No need to abort explicitly. */
1865                 break;
1866         case REF_TRANSACTION_PREPARED:
1867                 ret = refs->be->transaction_abort(refs, transaction, err);
1868                 break;
1869         case REF_TRANSACTION_CLOSED:
1870                 die("BUG: abort called on a closed reference transaction");
1871                 break;
1872         default:
1873                 die("BUG: unexpected reference transaction state");
1874                 break;
1875         }
1876
1877         ref_transaction_free(transaction);
1878         return ret;
1879 }
1880
1881 int ref_transaction_commit(struct ref_transaction *transaction,
1882                            struct strbuf *err)
1883 {
1884         struct ref_store *refs = transaction->ref_store;
1885         int ret;
1886
1887         switch (transaction->state) {
1888         case REF_TRANSACTION_OPEN:
1889                 /* Need to prepare first. */
1890                 ret = ref_transaction_prepare(transaction, err);
1891                 if (ret)
1892                         return ret;
1893                 break;
1894         case REF_TRANSACTION_PREPARED:
1895                 /* Fall through to finish. */
1896                 break;
1897         case REF_TRANSACTION_CLOSED:
1898                 die("BUG: commit called on a closed reference transaction");
1899                 break;
1900         default:
1901                 die("BUG: unexpected reference transaction state");
1902                 break;
1903         }
1904
1905         return refs->be->transaction_finish(refs, transaction, err);
1906 }
1907
1908 int refs_verify_refname_available(struct ref_store *refs,
1909                                   const char *refname,
1910                                   const struct string_list *extras,
1911                                   const struct string_list *skip,
1912                                   struct strbuf *err)
1913 {
1914         const char *slash;
1915         const char *extra_refname;
1916         struct strbuf dirname = STRBUF_INIT;
1917         struct strbuf referent = STRBUF_INIT;
1918         struct object_id oid;
1919         unsigned int type;
1920         struct ref_iterator *iter;
1921         int ok;
1922         int ret = -1;
1923
1924         /*
1925          * For the sake of comments in this function, suppose that
1926          * refname is "refs/foo/bar".
1927          */
1928
1929         assert(err);
1930
1931         strbuf_grow(&dirname, strlen(refname) + 1);
1932         for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
1933                 /* Expand dirname to the new prefix, not including the trailing slash: */
1934                 strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
1935
1936                 /*
1937                  * We are still at a leading dir of the refname (e.g.,
1938                  * "refs/foo"; if there is a reference with that name,
1939                  * it is a conflict, *unless* it is in skip.
1940                  */
1941                 if (skip && string_list_has_string(skip, dirname.buf))
1942                         continue;
1943
1944                 if (!refs_read_raw_ref(refs, dirname.buf, &oid, &referent, &type)) {
1945                         strbuf_addf(err, "'%s' exists; cannot create '%s'",
1946                                     dirname.buf, refname);
1947                         goto cleanup;
1948                 }
1949
1950                 if (extras && string_list_has_string(extras, dirname.buf)) {
1951                         strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1952                                     refname, dirname.buf);
1953                         goto cleanup;
1954                 }
1955         }
1956
1957         /*
1958          * We are at the leaf of our refname (e.g., "refs/foo/bar").
1959          * There is no point in searching for a reference with that
1960          * name, because a refname isn't considered to conflict with
1961          * itself. But we still need to check for references whose
1962          * names are in the "refs/foo/bar/" namespace, because they
1963          * *do* conflict.
1964          */
1965         strbuf_addstr(&dirname, refname + dirname.len);
1966         strbuf_addch(&dirname, '/');
1967
1968         iter = refs_ref_iterator_begin(refs, dirname.buf, 0,
1969                                        DO_FOR_EACH_INCLUDE_BROKEN);
1970         while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
1971                 if (skip &&
1972                     string_list_has_string(skip, iter->refname))
1973                         continue;
1974
1975                 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1976                             iter->refname, refname);
1977                 ref_iterator_abort(iter);
1978                 goto cleanup;
1979         }
1980
1981         if (ok != ITER_DONE)
1982                 die("BUG: error while iterating over references");
1983
1984         extra_refname = find_descendant_ref(dirname.buf, extras, skip);
1985         if (extra_refname)
1986                 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1987                             refname, extra_refname);
1988         else
1989                 ret = 0;
1990
1991 cleanup:
1992         strbuf_release(&referent);
1993         strbuf_release(&dirname);
1994         return ret;
1995 }
1996
1997 int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1998 {
1999         struct ref_iterator *iter;
2000
2001         iter = refs->be->reflog_iterator_begin(refs);
2002
2003         return do_for_each_ref_iterator(iter, fn, cb_data);
2004 }
2005
2006 int for_each_reflog(each_ref_fn fn, void *cb_data)
2007 {
2008         return refs_for_each_reflog(get_main_ref_store(the_repository), fn, cb_data);
2009 }
2010
2011 int refs_for_each_reflog_ent_reverse(struct ref_store *refs,
2012                                      const char *refname,
2013                                      each_reflog_ent_fn fn,
2014                                      void *cb_data)
2015 {
2016         return refs->be->for_each_reflog_ent_reverse(refs, refname,
2017                                                      fn, cb_data);
2018 }
2019
2020 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
2021                                 void *cb_data)
2022 {
2023         return refs_for_each_reflog_ent_reverse(get_main_ref_store(the_repository),
2024                                                 refname, fn, cb_data);
2025 }
2026
2027 int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname,
2028                              each_reflog_ent_fn fn, void *cb_data)
2029 {
2030         return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
2031 }
2032
2033 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
2034                         void *cb_data)
2035 {
2036         return refs_for_each_reflog_ent(get_main_ref_store(the_repository), refname,
2037                                         fn, cb_data);
2038 }
2039
2040 int refs_reflog_exists(struct ref_store *refs, const char *refname)
2041 {
2042         return refs->be->reflog_exists(refs, refname);
2043 }
2044
2045 int reflog_exists(const char *refname)
2046 {
2047         return refs_reflog_exists(get_main_ref_store(the_repository), refname);
2048 }
2049
2050 int refs_create_reflog(struct ref_store *refs, const char *refname,
2051                        int force_create, struct strbuf *err)
2052 {
2053         return refs->be->create_reflog(refs, refname, force_create, err);
2054 }
2055
2056 int safe_create_reflog(const char *refname, int force_create,
2057                        struct strbuf *err)
2058 {
2059         return refs_create_reflog(get_main_ref_store(the_repository), refname,
2060                                   force_create, err);
2061 }
2062
2063 int refs_delete_reflog(struct ref_store *refs, const char *refname)
2064 {
2065         return refs->be->delete_reflog(refs, refname);
2066 }
2067
2068 int delete_reflog(const char *refname)
2069 {
2070         return refs_delete_reflog(get_main_ref_store(the_repository), refname);
2071 }
2072
2073 int refs_reflog_expire(struct ref_store *refs,
2074                        const char *refname, const struct object_id *oid,
2075                        unsigned int flags,
2076                        reflog_expiry_prepare_fn prepare_fn,
2077                        reflog_expiry_should_prune_fn should_prune_fn,
2078                        reflog_expiry_cleanup_fn cleanup_fn,
2079                        void *policy_cb_data)
2080 {
2081         return refs->be->reflog_expire(refs, refname, oid, flags,
2082                                        prepare_fn, should_prune_fn,
2083                                        cleanup_fn, policy_cb_data);
2084 }
2085
2086 int reflog_expire(const char *refname, const struct object_id *oid,
2087                   unsigned int flags,
2088                   reflog_expiry_prepare_fn prepare_fn,
2089                   reflog_expiry_should_prune_fn should_prune_fn,
2090                   reflog_expiry_cleanup_fn cleanup_fn,
2091                   void *policy_cb_data)
2092 {
2093         return refs_reflog_expire(get_main_ref_store(the_repository),
2094                                   refname, oid, flags,
2095                                   prepare_fn, should_prune_fn,
2096                                   cleanup_fn, policy_cb_data);
2097 }
2098
2099 int initial_ref_transaction_commit(struct ref_transaction *transaction,
2100                                    struct strbuf *err)
2101 {
2102         struct ref_store *refs = transaction->ref_store;
2103
2104         return refs->be->initial_transaction_commit(refs, transaction, err);
2105 }
2106
2107 int refs_delete_refs(struct ref_store *refs, const char *msg,
2108                      struct string_list *refnames, unsigned int flags)
2109 {
2110         return refs->be->delete_refs(refs, msg, refnames, flags);
2111 }
2112
2113 int delete_refs(const char *msg, struct string_list *refnames,
2114                 unsigned int flags)
2115 {
2116         return refs_delete_refs(get_main_ref_store(the_repository), msg, refnames, flags);
2117 }
2118
2119 int refs_rename_ref(struct ref_store *refs, const char *oldref,
2120                     const char *newref, const char *logmsg)
2121 {
2122         return refs->be->rename_ref(refs, oldref, newref, logmsg);
2123 }
2124
2125 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
2126 {
2127         return refs_rename_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2128 }
2129
2130 int refs_copy_existing_ref(struct ref_store *refs, const char *oldref,
2131                     const char *newref, const char *logmsg)
2132 {
2133         return refs->be->copy_ref(refs, oldref, newref, logmsg);
2134 }
2135
2136 int copy_existing_ref(const char *oldref, const char *newref, const char *logmsg)
2137 {
2138         return refs_copy_existing_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2139 }