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