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                         die("could not read ref '%s'", pseudoref);
 686                 if (oidcmp(&actual_old_oid, old_oid)) {
 687                         strbuf_addf(err, "unexpected sha1 when writing '%s'", pseudoref);
 688                         rollback_lock_file(&lock);
 689                         goto done;
 690                 }
 691         }
 692
 693         if (write_in_full(fd, buf.buf, buf.len) < 0) {
 694                 strbuf_addf(err, "could not write to '%s'", filename);
 695                 rollback_lock_file(&lock);
 696                 goto done;
 697         }
 698
 699         commit_lock_file(&lock);
 700         ret = 0;
 701 done:
 702         strbuf_release(&buf);
 703         return ret;
 704 }
 705
 706 static int delete_pseudoref(const char *pseudoref, const struct object_id *old_oid)
 707 {
 708         const char *filename;
 709
 710         filename = git_path("%s", pseudoref);
 711
 712         if (old_oid && !is_null_oid(old_oid)) {
 713                 struct lock_file lock = LOCK_INIT;
 714                 int fd;
 715                 struct object_id actual_old_oid;
 716
 717                 fd = hold_lock_file_for_update_timeout(
 718                                 &lock, filename, 0,
 719                                 get_files_ref_lock_timeout_ms());
 720                 if (fd < 0) {
 721                         error_errno(_("could not open '%s' for writing"),
 722                                     filename);
 723                         return -1;
 724                 }
 725                 if (read_ref(pseudoref, &actual_old_oid))
 726                         die("could not read ref '%s'", pseudoref);
 727                 if (oidcmp(&actual_old_oid, old_oid)) {
 728                         warning("Unexpected sha1 when deleting %s", pseudoref);
 729                         rollback_lock_file(&lock);
 730                         return -1;
 731                 }
 732
 733                 unlink(filename);
 734                 rollback_lock_file(&lock);
 735         } else {
 736                 unlink(filename);
 737         }
 738
 739         return 0;
 740 }
 741
 742 int refs_delete_ref(struct ref_store *refs, const char *msg,
 743                     const char *refname,
 744                     const struct object_id *old_oid,
 745                     unsigned int flags)
 746 {
 747         struct ref_transaction *transaction;
 748         struct strbuf err = STRBUF_INIT;
 749
 750         if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
 751                 assert(refs == get_main_ref_store(the_repository));
 752                 return delete_pseudoref(refname, old_oid);
 753         }
 754
 755         transaction = ref_store_transaction_begin(refs, &err);
 756         if (!transaction ||
 757             ref_transaction_delete(transaction, refname, old_oid,
 758                                    flags, msg, &err) ||
 759             ref_transaction_commit(transaction, &err)) {
 760                 error("%s", err.buf);
 761                 ref_transaction_free(transaction);
 762                 strbuf_release(&err);
 763                 return 1;
 764         }
 765         ref_transaction_free(transaction);
 766         strbuf_release(&err);
 767         return 0;
 768 }
 769
 770 int delete_ref(const char *msg, const char *refname,
 771                const struct object_id *old_oid, unsigned int flags)
 772 {
 773         return refs_delete_ref(get_main_ref_store(the_repository), msg, refname,
 774                                old_oid, flags);
 775 }
 776
 777 int copy_reflog_msg(char *buf, const char *msg)
 778 {
 779         char *cp = buf;
 780         char c;
 781         int wasspace = 1;
 782
 783         *cp++ = '\t';
 784         while ((c = *msg++)) {
 785                 if (wasspace && isspace(c))
 786                         continue;
 787                 wasspace = isspace(c);
 788                 if (wasspace)
 789                         c = ' ';
 790                 *cp++ = c;
 791         }
 792         while (buf < cp && isspace(cp[-1]))
 793                 cp--;
 794         *cp++ = '\n';
 795         return cp - buf;
 796 }
 797
 798 int should_autocreate_reflog(const char *refname)
 799 {
 800         switch (log_all_ref_updates) {
 801         case LOG_REFS_ALWAYS:
 802                 return 1;
 803         case LOG_REFS_NORMAL:
 804                 return starts_with(refname, "refs/heads/") ||
 805                         starts_with(refname, "refs/remotes/") ||
 806                         starts_with(refname, "refs/notes/") ||
 807                         !strcmp(refname, "HEAD");
 808         default:
 809                 return 0;
 810         }
 811 }
 812
 813 int is_branch(const char *refname)
 814 {
 815         return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
 816 }
 817
 818 struct read_ref_at_cb {
 819         const char *refname;
 820         timestamp_t at_time;
 821         int cnt;
 822         int reccnt;
 823         struct object_id *oid;
 824         int found_it;
 825
 826         struct object_id ooid;
 827         struct object_id noid;
 828         int tz;
 829         timestamp_t date;
 830         char **msg;
 831         timestamp_t *cutoff_time;
 832         int *cutoff_tz;
 833         int *cutoff_cnt;
 834 };
 835
 836 static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
 837                 const char *email, timestamp_t timestamp, int tz,
 838                 const char *message, void *cb_data)
 839 {
 840         struct read_ref_at_cb *cb = cb_data;
 841
 842         cb->reccnt++;
 843         cb->tz = tz;
 844         cb->date = timestamp;
 845
 846         if (timestamp <= cb->at_time || cb->cnt == 0) {
 847                 if (cb->msg)
 848                         *cb->msg = xstrdup(message);
 849                 if (cb->cutoff_time)
 850                         *cb->cutoff_time = timestamp;
 851                 if (cb->cutoff_tz)
 852                         *cb->cutoff_tz = tz;
 853                 if (cb->cutoff_cnt)
 854                         *cb->cutoff_cnt = cb->reccnt - 1;
 855                 /*
 856                  * we have not yet updated cb->[n|o]oid so they still
 857                  * hold the values for the previous record.
 858                  */
 859                 if (!is_null_oid(&cb->ooid)) {
 860                         oidcpy(cb->oid, noid);
 861                         if (oidcmp(&cb->ooid, noid))
 862                                 warning("Log for ref %s has gap after %s.",
 863                                         cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
 864                 }
 865                 else if (cb->date == cb->at_time)
 866                         oidcpy(cb->oid, noid);
 867                 else if (oidcmp(noid, cb->oid))
 868                         warning("Log for ref %s unexpectedly ended on %s.",
 869                                 cb->refname, show_date(cb->date, cb->tz,
 870                                                        DATE_MODE(RFC2822)));
 871                 oidcpy(&cb->ooid, ooid);
 872                 oidcpy(&cb->noid, noid);
 873                 cb->found_it = 1;
 874                 return 1;
 875         }
 876         oidcpy(&cb->ooid, ooid);
 877         oidcpy(&cb->noid, noid);
 878         if (cb->cnt > 0)
 879                 cb->cnt--;
 880         return 0;
 881 }
 882
 883 static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
 884                                   const char *email, timestamp_t timestamp,
 885                                   int tz, const char *message, void *cb_data)
 886 {
 887         struct read_ref_at_cb *cb = cb_data;
 888
 889         if (cb->msg)
 890                 *cb->msg = xstrdup(message);
 891         if (cb->cutoff_time)
 892                 *cb->cutoff_time = timestamp;
 893         if (cb->cutoff_tz)
 894                 *cb->cutoff_tz = tz;
 895         if (cb->cutoff_cnt)
 896                 *cb->cutoff_cnt = cb->reccnt;
 897         oidcpy(cb->oid, ooid);
 898         if (is_null_oid(cb->oid))
 899                 oidcpy(cb->oid, noid);
 900         /* We just want the first entry */
 901         return 1;
 902 }
 903
 904 int read_ref_at(const char *refname, unsigned int flags, timestamp_t at_time, int cnt,
 905                 struct object_id *oid, char **msg,
 906                 timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
 907 {
 908         struct read_ref_at_cb cb;
 909
 910         memset(&cb, 0, sizeof(cb));
 911         cb.refname = refname;
 912         cb.at_time = at_time;
 913         cb.cnt = cnt;
 914         cb.msg = msg;
 915         cb.cutoff_time = cutoff_time;
 916         cb.cutoff_tz = cutoff_tz;
 917         cb.cutoff_cnt = cutoff_cnt;
 918         cb.oid = oid;
 919
 920         for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
 921
 922         if (!cb.reccnt) {
 923                 if (flags & GET_OID_QUIETLY)
 924                         exit(128);
 925                 else
 926                         die("Log for %s is empty.", refname);
 927         }
 928         if (cb.found_it)
 929                 return 0;
 930
 931         for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
 932
 933         return 1;
 934 }
 935
 936 struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs,
 937                                                     struct strbuf *err)
 938 {
 939         struct ref_transaction *tr;
 940         assert(err);
 941
 942         tr = xcalloc(1, sizeof(struct ref_transaction));
 943         tr->ref_store = refs;
 944         return tr;
 945 }
 946
 947 struct ref_transaction *ref_transaction_begin(struct strbuf *err)
 948 {
 949         return ref_store_transaction_begin(get_main_ref_store(the_repository), err);
 950 }
 951
 952 void ref_transaction_free(struct ref_transaction *transaction)
 953 {
 954         size_t i;
 955
 956         if (!transaction)
 957                 return;
 958
 959         switch (transaction->state) {
 960         case REF_TRANSACTION_OPEN:
 961         case REF_TRANSACTION_CLOSED:
 962                 /* OK */
 963                 break;
 964         case REF_TRANSACTION_PREPARED:
 965                 BUG("free called on a prepared reference transaction");
 966                 break;
 967         default:
 968                 BUG("unexpected reference transaction state");
 969                 break;
 970         }
 971
 972         for (i = 0; i < transaction->nr; i++) {
 973                 free(transaction->updates[i]->msg);
 974                 free(transaction->updates[i]);
 975         }
 976         free(transaction->updates);
 977         free(transaction);
 978 }
 979
 980 struct ref_update *ref_transaction_add_update(
 981                 struct ref_transaction *transaction,
 982                 const char *refname, unsigned int flags,
 983                 const struct object_id *new_oid,
 984                 const struct object_id *old_oid,
 985                 const char *msg)
 986 {
 987         struct ref_update *update;
 988
 989         if (transaction->state != REF_TRANSACTION_OPEN)
 990                 BUG("update called for transaction that is not open");
 991
 992         FLEX_ALLOC_STR(update, refname, refname);
 993         ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
 994         transaction->updates[transaction->nr++] = update;
 995
 996         update->flags = flags;
 997
 998         if (flags & REF_HAVE_NEW)
 999                 oidcpy(&update->new_oid, new_oid);
1000         if (flags & REF_HAVE_OLD)
1001                 oidcpy(&update->old_oid, old_oid);
1002         update->msg = xstrdup_or_null(msg);
1003         return update;
1004 }
1005
1006 int ref_transaction_update(struct ref_transaction *transaction,
1007                            const char *refname,
1008                            const struct object_id *new_oid,
1009                            const struct object_id *old_oid,
1010                            unsigned int flags, const char *msg,
1011                            struct strbuf *err)
1012 {
1013         assert(err);
1014
1015         if ((new_oid && !is_null_oid(new_oid)) ?
1016             check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
1017             !refname_is_safe(refname)) {
1018                 strbuf_addf(err, "refusing to update ref with bad name '%s'",
1019                             refname);
1020                 return -1;
1021         }
1022
1023         if (flags & ~REF_TRANSACTION_UPDATE_ALLOWED_FLAGS)
1024                 BUG("illegal flags 0x%x passed to ref_transaction_update()", flags);
1025
1026         flags |= (new_oid ? REF_HAVE_NEW : 0) | (old_oid ? REF_HAVE_OLD : 0);
1027
1028         ref_transaction_add_update(transaction, refname, flags,
1029                                    new_oid, old_oid, msg);
1030         return 0;
1031 }
1032
1033 int ref_transaction_create(struct ref_transaction *transaction,
1034                            const char *refname,
1035                            const struct object_id *new_oid,
1036                            unsigned int flags, const char *msg,
1037                            struct strbuf *err)
1038 {
1039         if (!new_oid || is_null_oid(new_oid))
1040                 BUG("create called without valid new_oid");
1041         return ref_transaction_update(transaction, refname, new_oid,
1042                                       &null_oid, flags, msg, err);
1043 }
1044
1045 int ref_transaction_delete(struct ref_transaction *transaction,
1046                            const char *refname,
1047                            const struct object_id *old_oid,
1048                            unsigned int flags, const char *msg,
1049                            struct strbuf *err)
1050 {
1051         if (old_oid && is_null_oid(old_oid))
1052                 BUG("delete called with old_oid set to zeros");
1053         return ref_transaction_update(transaction, refname,
1054                                       &null_oid, old_oid,
1055                                       flags, msg, err);
1056 }
1057
1058 int ref_transaction_verify(struct ref_transaction *transaction,
1059                            const char *refname,
1060                            const struct object_id *old_oid,
1061                            unsigned int flags,
1062                            struct strbuf *err)
1063 {
1064         if (!old_oid)
1065                 BUG("verify called with old_oid set to NULL");
1066         return ref_transaction_update(transaction, refname,
1067                                       NULL, old_oid,
1068                                       flags, NULL, err);
1069 }
1070
1071 int refs_update_ref(struct ref_store *refs, const char *msg,
1072                     const char *refname, const struct object_id *new_oid,
1073                     const struct object_id *old_oid, unsigned int flags,
1074                     enum action_on_err onerr)
1075 {
1076         struct ref_transaction *t = NULL;
1077         struct strbuf err = STRBUF_INIT;
1078         int ret = 0;
1079
1080         if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
1081                 assert(refs == get_main_ref_store(the_repository));
1082                 ret = write_pseudoref(refname, new_oid, old_oid, &err);
1083         } else {
1084                 t = ref_store_transaction_begin(refs, &err);
1085                 if (!t ||
1086                     ref_transaction_update(t, refname, new_oid, old_oid,
1087                                            flags, msg, &err) ||
1088                     ref_transaction_commit(t, &err)) {
1089                         ret = 1;
1090                         ref_transaction_free(t);
1091                 }
1092         }
1093         if (ret) {
1094                 const char *str = "update_ref failed for ref '%s': %s";
1095
1096                 switch (onerr) {
1097                 case UPDATE_REFS_MSG_ON_ERR:
1098                         error(str, refname, err.buf);
1099                         break;
1100                 case UPDATE_REFS_DIE_ON_ERR:
1101                         die(str, refname, err.buf);
1102                         break;
1103                 case UPDATE_REFS_QUIET_ON_ERR:
1104                         break;
1105                 }
1106                 strbuf_release(&err);
1107                 return 1;
1108         }
1109         strbuf_release(&err);
1110         if (t)
1111                 ref_transaction_free(t);
1112         return 0;
1113 }
1114
1115 int update_ref(const char *msg, const char *refname,
1116                const struct object_id *new_oid,
1117                const struct object_id *old_oid,
1118                unsigned int flags, enum action_on_err onerr)
1119 {
1120         return refs_update_ref(get_main_ref_store(the_repository), msg, refname, new_oid,
1121                                old_oid, flags, onerr);
1122 }
1123
1124 char *shorten_unambiguous_ref(const char *refname, int strict)
1125 {
1126         int i;
1127         static char **scanf_fmts;
1128         static int nr_rules;
1129         char *short_name;
1130         struct strbuf resolved_buf = STRBUF_INIT;
1131
1132         if (!nr_rules) {
1133                 /*
1134                  * Pre-generate scanf formats from ref_rev_parse_rules[].
1135                  * Generate a format suitable for scanf from a
1136                  * ref_rev_parse_rules rule by interpolating "%s" at the
1137                  * location of the "%.*s".
1138                  */
1139                 size_t total_len = 0;
1140                 size_t offset = 0;
1141
1142                 /* the rule list is NULL terminated, count them first */
1143                 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
1144                         /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
1145                         total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
1146
1147                 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
1148
1149                 offset = 0;
1150                 for (i = 0; i < nr_rules; i++) {
1151                         assert(offset < total_len);
1152                         scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
1153                         offset += snprintf(scanf_fmts[i], total_len - offset,
1154                                            ref_rev_parse_rules[i], 2, "%s") + 1;
1155                 }
1156         }
1157
1158         /* bail out if there are no rules */
1159         if (!nr_rules)
1160                 return xstrdup(refname);
1161
1162         /* buffer for scanf result, at most refname must fit */
1163         short_name = xstrdup(refname);
1164
1165         /* skip first rule, it will always match */
1166         for (i = nr_rules - 1; i > 0 ; --i) {
1167                 int j;
1168                 int rules_to_fail = i;
1169                 int short_name_len;
1170
1171                 if (1 != sscanf(refname, scanf_fmts[i], short_name))
1172                         continue;
1173
1174                 short_name_len = strlen(short_name);
1175
1176                 /*
1177                  * in strict mode, all (except the matched one) rules
1178                  * must fail to resolve to a valid non-ambiguous ref
1179                  */
1180                 if (strict)
1181                         rules_to_fail = nr_rules;
1182
1183                 /*
1184                  * check if the short name resolves to a valid ref,
1185                  * but use only rules prior to the matched one
1186                  */
1187                 for (j = 0; j < rules_to_fail; j++) {
1188                         const char *rule = ref_rev_parse_rules[j];
1189
1190                         /* skip matched rule */
1191                         if (i == j)
1192                                 continue;
1193
1194                         /*
1195                          * the short name is ambiguous, if it resolves
1196                          * (with this previous rule) to a valid ref
1197                          * read_ref() returns 0 on success
1198                          */
1199                         strbuf_reset(&resolved_buf);
1200                         strbuf_addf(&resolved_buf, rule,
1201                                     short_name_len, short_name);
1202                         if (ref_exists(resolved_buf.buf))
1203                                 break;
1204                 }
1205
1206                 /*
1207                  * short name is non-ambiguous if all previous rules
1208                  * haven't resolved to a valid ref
1209                  */
1210                 if (j == rules_to_fail) {
1211                         strbuf_release(&resolved_buf);
1212                         return short_name;
1213                 }
1214         }
1215
1216         strbuf_release(&resolved_buf);
1217         free(short_name);
1218         return xstrdup(refname);
1219 }
1220
1221 static struct string_list *hide_refs;
1222
1223 int parse_hide_refs_config(const char *var, const char *value, const char *section)
1224 {
1225         const char *key;
1226         if (!strcmp("transfer.hiderefs", var) ||
1227             (!parse_config_key(var, section, NULL, NULL, &key) &&
1228              !strcmp(key, "hiderefs"))) {
1229                 char *ref;
1230                 int len;
1231
1232                 if (!value)
1233                         return config_error_nonbool(var);
1234                 ref = xstrdup(value);
1235                 len = strlen(ref);
1236                 while (len && ref[len - 1] == '/')
1237                         ref[--len] = '\0';
1238                 if (!hide_refs) {
1239                         hide_refs = xcalloc(1, sizeof(*hide_refs));
1240                         hide_refs->strdup_strings = 1;
1241                 }
1242                 string_list_append(hide_refs, ref);
1243         }
1244         return 0;
1245 }
1246
1247 int ref_is_hidden(const char *refname, const char *refname_full)
1248 {
1249         int i;
1250
1251         if (!hide_refs)
1252                 return 0;
1253         for (i = hide_refs->nr - 1; i >= 0; i--) {
1254                 const char *match = hide_refs->items[i].string;
1255                 const char *subject;
1256                 int neg = 0;
1257                 const char *p;
1258
1259                 if (*match == '!') {
1260                         neg = 1;
1261                         match++;
1262                 }
1263
1264                 if (*match == '^') {
1265                         subject = refname_full;
1266                         match++;
1267                 } else {
1268                         subject = refname;
1269                 }
1270
1271                 /* refname can be NULL when namespaces are used. */
1272                 if (subject &&
1273                     skip_prefix(subject, match, &p) &&
1274                     (!*p || *p == '/'))
1275                         return !neg;
1276         }
1277         return 0;
1278 }
1279
1280 const char *find_descendant_ref(const char *dirname,
1281                                 const struct string_list *extras,
1282                                 const struct string_list *skip)
1283 {
1284         int pos;
1285
1286         if (!extras)
1287                 return NULL;
1288
1289         /*
1290          * Look at the place where dirname would be inserted into
1291          * extras. If there is an entry at that position that starts
1292          * with dirname (remember, dirname includes the trailing
1293          * slash) and is not in skip, then we have a conflict.
1294          */
1295         for (pos = string_list_find_insert_index(extras, dirname, 0);
1296              pos < extras->nr; pos++) {
1297                 const char *extra_refname = extras->items[pos].string;
1298
1299                 if (!starts_with(extra_refname, dirname))
1300                         break;
1301
1302                 if (!skip || !string_list_has_string(skip, extra_refname))
1303                         return extra_refname;
1304         }
1305         return NULL;
1306 }
1307
1308 int refs_rename_ref_available(struct ref_store *refs,
1309                               const char *old_refname,
1310                               const char *new_refname)
1311 {
1312         struct string_list skip = STRING_LIST_INIT_NODUP;
1313         struct strbuf err = STRBUF_INIT;
1314         int ok;
1315
1316         string_list_insert(&skip, old_refname);
1317         ok = !refs_verify_refname_available(refs, new_refname,
1318                                             NULL, &skip, &err);
1319         if (!ok)
1320                 error("%s", err.buf);
1321
1322         string_list_clear(&skip, 0);
1323         strbuf_release(&err);
1324         return ok;
1325 }
1326
1327 int refs_head_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1328 {
1329         struct object_id oid;
1330         int flag;
1331
1332         if (!refs_read_ref_full(refs, "HEAD", RESOLVE_REF_READING,
1333                                 &oid, &flag))
1334                 return fn("HEAD", &oid, flag, cb_data);
1335
1336         return 0;
1337 }
1338
1339 int head_ref(each_ref_fn fn, void *cb_data)
1340 {
1341         return refs_head_ref(get_main_ref_store(the_repository), fn, cb_data);
1342 }
1343
1344 struct ref_iterator *refs_ref_iterator_begin(
1345                 struct ref_store *refs,
1346                 const char *prefix, int trim, int flags)
1347 {
1348         struct ref_iterator *iter;
1349
1350         if (ref_paranoia < 0)
1351                 ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
1352         if (ref_paranoia)
1353                 flags |= DO_FOR_EACH_INCLUDE_BROKEN;
1354
1355         iter = refs->be->iterator_begin(refs, prefix, flags);
1356
1357         /*
1358          * `iterator_begin()` already takes care of prefix, but we
1359          * might need to do some trimming:
1360          */
1361         if (trim)
1362                 iter = prefix_ref_iterator_begin(iter, "", trim);
1363
1364         /* Sanity check for subclasses: */
1365         if (!iter->ordered)
1366                 BUG("reference iterator is not ordered");
1367
1368         return iter;
1369 }
1370
1371 /*
1372  * Call fn for each reference in the specified submodule for which the
1373  * refname begins with prefix. If trim is non-zero, then trim that
1374  * many characters off the beginning of each refname before passing
1375  * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1376  * include broken references in the iteration. If fn ever returns a
1377  * non-zero value, stop the iteration and return that value;
1378  * otherwise, return 0.
1379  */
1380 static int do_for_each_ref(struct ref_store *refs, const char *prefix,
1381                            each_ref_fn fn, int trim, int flags, void *cb_data)
1382 {
1383         struct ref_iterator *iter;
1384
1385         if (!refs)
1386                 return 0;
1387
1388         iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1389
1390         return do_for_each_ref_iterator(iter, fn, cb_data);
1391 }
1392
1393 int refs_for_each_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1394 {
1395         return do_for_each_ref(refs, "", fn, 0, 0, cb_data);
1396 }
1397
1398 int for_each_ref(each_ref_fn fn, void *cb_data)
1399 {
1400         return refs_for_each_ref(get_main_ref_store(the_repository), fn, cb_data);
1401 }
1402
1403 int refs_for_each_ref_in(struct ref_store *refs, const char *prefix,
1404                          each_ref_fn fn, void *cb_data)
1405 {
1406         return do_for_each_ref(refs, prefix, fn, strlen(prefix), 0, cb_data);
1407 }
1408
1409 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1410 {
1411         return refs_for_each_ref_in(get_main_ref_store(the_repository), prefix, fn, cb_data);
1412 }
1413
1414 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1415 {
1416         unsigned int flag = 0;
1417
1418         if (broken)
1419                 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1420         return do_for_each_ref(get_main_ref_store(the_repository),
1421                                prefix, fn, 0, flag, cb_data);
1422 }
1423
1424 int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix,
1425                              each_ref_fn fn, void *cb_data,
1426                              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(refs, prefix, fn, 0, flag, cb_data);
1433 }
1434
1435 int for_each_replace_ref(struct repository *r, each_ref_fn fn, void *cb_data)
1436 {
1437         return do_for_each_ref(get_main_ref_store(r),
1438                                git_replace_ref_base, fn,
1439                                strlen(git_replace_ref_base),
1440                                DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1441 }
1442
1443 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1444 {
1445         struct strbuf buf = STRBUF_INIT;
1446         int ret;
1447         strbuf_addf(&buf, "%srefs/", get_git_namespace());
1448         ret = do_for_each_ref(get_main_ref_store(the_repository),
1449                               buf.buf, fn, 0, 0, cb_data);
1450         strbuf_release(&buf);
1451         return ret;
1452 }
1453
1454 int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1455 {
1456         return do_for_each_ref(refs, "", fn, 0,
1457                                DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1458 }
1459
1460 int for_each_rawref(each_ref_fn fn, void *cb_data)
1461 {
1462         return refs_for_each_rawref(get_main_ref_store(the_repository), fn, cb_data);
1463 }
1464
1465 int refs_read_raw_ref(struct ref_store *ref_store,
1466                       const char *refname, struct object_id *oid,
1467                       struct strbuf *referent, unsigned int *type)
1468 {
1469         return ref_store->be->read_raw_ref(ref_store, refname, oid, referent, type);
1470 }
1471
1472 /* This function needs to return a meaningful errno on failure */
1473 const char *refs_resolve_ref_unsafe(struct ref_store *refs,
1474                                     const char *refname,
1475                                     int resolve_flags,
1476                                     struct object_id *oid, int *flags)
1477 {
1478         static struct strbuf sb_refname = STRBUF_INIT;
1479         struct object_id unused_oid;
1480         int unused_flags;
1481         int symref_count;
1482
1483         if (!oid)
1484                 oid = &unused_oid;
1485         if (!flags)
1486                 flags = &unused_flags;
1487
1488         *flags = 0;
1489
1490         if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1491                 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1492                     !refname_is_safe(refname)) {
1493                         errno = EINVAL;
1494                         return NULL;
1495                 }
1496
1497                 /*
1498                  * dwim_ref() uses REF_ISBROKEN to distinguish between
1499                  * missing refs and refs that were present but invalid,
1500                  * to complain about the latter to stderr.
1501                  *
1502                  * We don't know whether the ref exists, so don't set
1503                  * REF_ISBROKEN yet.
1504                  */
1505                 *flags |= REF_BAD_NAME;
1506         }
1507
1508         for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1509                 unsigned int read_flags = 0;
1510
1511                 if (refs_read_raw_ref(refs, refname,
1512                                       oid, &sb_refname, &read_flags)) {
1513                         *flags |= read_flags;
1514
1515                         /* In reading mode, refs must eventually resolve */
1516                         if (resolve_flags & RESOLVE_REF_READING)
1517                                 return NULL;
1518
1519                         /*
1520                          * Otherwise a missing ref is OK. But the files backend
1521                          * may show errors besides ENOENT if there are
1522                          * similarly-named refs.
1523                          */
1524                         if (errno != ENOENT &&
1525                             errno != EISDIR &&
1526                             errno != ENOTDIR)
1527                                 return NULL;
1528
1529                         oidclr(oid);
1530                         if (*flags & REF_BAD_NAME)
1531                                 *flags |= REF_ISBROKEN;
1532                         return refname;
1533                 }
1534
1535                 *flags |= read_flags;
1536
1537                 if (!(read_flags & REF_ISSYMREF)) {
1538                         if (*flags & REF_BAD_NAME) {
1539                                 oidclr(oid);
1540                                 *flags |= REF_ISBROKEN;
1541                         }
1542                         return refname;
1543                 }
1544
1545                 refname = sb_refname.buf;
1546                 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1547                         oidclr(oid);
1548                         return refname;
1549                 }
1550                 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1551                         if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1552                             !refname_is_safe(refname)) {
1553                                 errno = EINVAL;
1554                                 return NULL;
1555                         }
1556
1557                         *flags |= REF_ISBROKEN | REF_BAD_NAME;
1558                 }
1559         }
1560
1561         errno = ELOOP;
1562         return NULL;
1563 }
1564
1565 /* backend functions */
1566 int refs_init_db(struct strbuf *err)
1567 {
1568         struct ref_store *refs = get_main_ref_store(the_repository);
1569
1570         return refs->be->init_db(refs, err);
1571 }
1572
1573 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1574                                struct object_id *oid, int *flags)
1575 {
1576         return refs_resolve_ref_unsafe(get_main_ref_store(the_repository), refname,
1577                                        resolve_flags, oid, flags);
1578 }
1579
1580 int resolve_gitlink_ref(const char *submodule, const char *refname,
1581                         struct object_id *oid)
1582 {
1583         struct ref_store *refs;
1584         int flags;
1585
1586         refs = get_submodule_ref_store(submodule);
1587
1588         if (!refs)
1589                 return -1;
1590
1591         if (!refs_resolve_ref_unsafe(refs, refname, 0, oid, &flags) ||
1592             is_null_oid(oid))
1593                 return -1;
1594         return 0;
1595 }
1596
1597 struct ref_store_hash_entry
1598 {
1599         struct hashmap_entry ent; /* must be the first member! */
1600
1601         struct ref_store *refs;
1602
1603         /* NUL-terminated identifier of the ref store: */
1604         char name[FLEX_ARRAY];
1605 };
1606
1607 static int ref_store_hash_cmp(const void *unused_cmp_data,
1608                               const void *entry, const void *entry_or_key,
1609                               const void *keydata)
1610 {
1611         const struct ref_store_hash_entry *e1 = entry, *e2 = entry_or_key;
1612         const char *name = keydata ? keydata : e2->name;
1613
1614         return strcmp(e1->name, name);
1615 }
1616
1617 static struct ref_store_hash_entry *alloc_ref_store_hash_entry(
1618                 const char *name, struct ref_store *refs)
1619 {
1620         struct ref_store_hash_entry *entry;
1621
1622         FLEX_ALLOC_STR(entry, name, name);
1623         hashmap_entry_init(entry, strhash(name));
1624         entry->refs = refs;
1625         return entry;
1626 }
1627
1628 /* A hashmap of ref_stores, stored by submodule name: */
1629 static struct hashmap submodule_ref_stores;
1630
1631 /* A hashmap of ref_stores, stored by worktree id: */
1632 static struct hashmap worktree_ref_stores;
1633
1634 /*
1635  * Look up a ref store by name. If that ref_store hasn't been
1636  * registered yet, return NULL.
1637  */
1638 static struct ref_store *lookup_ref_store_map(struct hashmap *map,
1639                                               const char *name)
1640 {
1641         struct ref_store_hash_entry *entry;
1642
1643         if (!map->tablesize)
1644                 /* It's initialized on demand in register_ref_store(). */
1645                 return NULL;
1646
1647         entry = hashmap_get_from_hash(map, strhash(name), name);
1648         return entry ? entry->refs : NULL;
1649 }
1650
1651 /*
1652  * Create, record, and return a ref_store instance for the specified
1653  * gitdir.
1654  */
1655 static struct ref_store *ref_store_init(const char *gitdir,
1656                                         unsigned int flags)
1657 {
1658         const char *be_name = "files";
1659         struct ref_storage_be *be = find_ref_storage_backend(be_name);
1660         struct ref_store *refs;
1661
1662         if (!be)
1663                 BUG("reference backend %s is unknown", be_name);
1664
1665         refs = be->init(gitdir, flags);
1666         return refs;
1667 }
1668
1669 struct ref_store *get_main_ref_store(struct repository *r)
1670 {
1671         if (r->refs)
1672                 return r->refs;
1673
1674         if (!r->gitdir)
1675                 BUG("attempting to get main_ref_store outside of repository");
1676
1677         r->refs = ref_store_init(r->gitdir, REF_STORE_ALL_CAPS);
1678         return r->refs;
1679 }
1680
1681 /*
1682  * Associate a ref store with a name. It is a fatal error to call this
1683  * function twice for the same name.
1684  */
1685 static void register_ref_store_map(struct hashmap *map,
1686                                    const char *type,
1687                                    struct ref_store *refs,
1688                                    const char *name)
1689 {
1690         if (!map->tablesize)
1691                 hashmap_init(map, ref_store_hash_cmp, NULL, 0);
1692
1693         if (hashmap_put(map, alloc_ref_store_hash_entry(name, refs)))
1694                 BUG("%s ref_store '%s' initialized twice", type, name);
1695 }
1696
1697 struct ref_store *get_submodule_ref_store(const char *submodule)
1698 {
1699         struct strbuf submodule_sb = STRBUF_INIT;
1700         struct ref_store *refs;
1701         char *to_free = NULL;
1702         size_t len;
1703
1704         if (!submodule)
1705                 return NULL;
1706
1707         len = strlen(submodule);
1708         while (len && is_dir_sep(submodule[len - 1]))
1709                 len--;
1710         if (!len)
1711                 return NULL;
1712
1713         if (submodule[len])
1714                 /* We need to strip off one or more trailing slashes */
1715                 submodule = to_free = xmemdupz(submodule, len);
1716
1717         refs = lookup_ref_store_map(&submodule_ref_stores, submodule);
1718         if (refs)
1719                 goto done;
1720
1721         strbuf_addstr(&submodule_sb, submodule);
1722         if (!is_nonbare_repository_dir(&submodule_sb))
1723                 goto done;
1724
1725         if (submodule_to_gitdir(&submodule_sb, submodule))
1726                 goto done;
1727
1728         /* assume that add_submodule_odb() has been called */
1729         refs = ref_store_init(submodule_sb.buf,
1730                               REF_STORE_READ | REF_STORE_ODB);
1731         register_ref_store_map(&submodule_ref_stores, "submodule",
1732                                refs, submodule);
1733
1734 done:
1735         strbuf_release(&submodule_sb);
1736         free(to_free);
1737
1738         return refs;
1739 }
1740
1741 struct ref_store *get_worktree_ref_store(const struct worktree *wt)
1742 {
1743         struct ref_store *refs;
1744         const char *id;
1745
1746         if (wt->is_current)
1747                 return get_main_ref_store(the_repository);
1748
1749         id = wt->id ? wt->id : "/";
1750         refs = lookup_ref_store_map(&worktree_ref_stores, id);
1751         if (refs)
1752                 return refs;
1753
1754         if (wt->id)
1755                 refs = ref_store_init(git_common_path("worktrees/%s", wt->id),
1756                                       REF_STORE_ALL_CAPS);
1757         else
1758                 refs = ref_store_init(get_git_common_dir(),
1759                                       REF_STORE_ALL_CAPS);
1760
1761         if (refs)
1762                 register_ref_store_map(&worktree_ref_stores, "worktree",
1763                                        refs, id);
1764         return refs;
1765 }
1766
1767 void base_ref_store_init(struct ref_store *refs,
1768                          const struct ref_storage_be *be)
1769 {
1770         refs->be = be;
1771 }
1772
1773 /* backend functions */
1774 int refs_pack_refs(struct ref_store *refs, unsigned int flags)
1775 {
1776         return refs->be->pack_refs(refs, flags);
1777 }
1778
1779 int refs_peel_ref(struct ref_store *refs, const char *refname,
1780                   struct object_id *oid)
1781 {
1782         int flag;
1783         struct object_id base;
1784
1785         if (current_ref_iter && current_ref_iter->refname == refname) {
1786                 struct object_id peeled;
1787
1788                 if (ref_iterator_peel(current_ref_iter, &peeled))
1789                         return -1;
1790                 oidcpy(oid, &peeled);
1791                 return 0;
1792         }
1793
1794         if (refs_read_ref_full(refs, refname,
1795                                RESOLVE_REF_READING, &base, &flag))
1796                 return -1;
1797
1798         return peel_object(&base, oid);
1799 }
1800
1801 int peel_ref(const char *refname, struct object_id *oid)
1802 {
1803         return refs_peel_ref(get_main_ref_store(the_repository), refname, oid);
1804 }
1805
1806 int refs_create_symref(struct ref_store *refs,
1807                        const char *ref_target,
1808                        const char *refs_heads_master,
1809                        const char *logmsg)
1810 {
1811         return refs->be->create_symref(refs, ref_target,
1812                                        refs_heads_master,
1813                                        logmsg);
1814 }
1815
1816 int create_symref(const char *ref_target, const char *refs_heads_master,
1817                   const char *logmsg)
1818 {
1819         return refs_create_symref(get_main_ref_store(the_repository), ref_target,
1820                                   refs_heads_master, logmsg);
1821 }
1822
1823 int ref_update_reject_duplicates(struct string_list *refnames,
1824                                  struct strbuf *err)
1825 {
1826         size_t i, n = refnames->nr;
1827
1828         assert(err);
1829
1830         for (i = 1; i < n; i++) {
1831                 int cmp = strcmp(refnames->items[i - 1].string,
1832                                  refnames->items[i].string);
1833
1834                 if (!cmp) {
1835                         strbuf_addf(err,
1836                                     "multiple updates for ref '%s' not allowed.",
1837                                     refnames->items[i].string);
1838                         return 1;
1839                 } else if (cmp > 0) {
1840                         BUG("ref_update_reject_duplicates() received unsorted list");
1841                 }
1842         }
1843         return 0;
1844 }
1845
1846 int ref_transaction_prepare(struct ref_transaction *transaction,
1847                             struct strbuf *err)
1848 {
1849         struct ref_store *refs = transaction->ref_store;
1850
1851         switch (transaction->state) {
1852         case REF_TRANSACTION_OPEN:
1853                 /* Good. */
1854                 break;
1855         case REF_TRANSACTION_PREPARED:
1856                 BUG("prepare called twice on reference transaction");
1857                 break;
1858         case REF_TRANSACTION_CLOSED:
1859                 BUG("prepare called on a closed reference transaction");
1860                 break;
1861         default:
1862                 BUG("unexpected reference transaction state");
1863                 break;
1864         }
1865
1866         if (getenv(GIT_QUARANTINE_ENVIRONMENT)) {
1867                 strbuf_addstr(err,
1868                               _("ref updates forbidden inside quarantine environment"));
1869                 return -1;
1870         }
1871
1872         return refs->be->transaction_prepare(refs, transaction, err);
1873 }
1874
1875 int ref_transaction_abort(struct ref_transaction *transaction,
1876                           struct strbuf *err)
1877 {
1878         struct ref_store *refs = transaction->ref_store;
1879         int ret = 0;
1880
1881         switch (transaction->state) {
1882         case REF_TRANSACTION_OPEN:
1883                 /* No need to abort explicitly. */
1884                 break;
1885         case REF_TRANSACTION_PREPARED:
1886                 ret = refs->be->transaction_abort(refs, transaction, err);
1887                 break;
1888         case REF_TRANSACTION_CLOSED:
1889                 BUG("abort called on a closed reference transaction");
1890                 break;
1891         default:
1892                 BUG("unexpected reference transaction state");
1893                 break;
1894         }
1895
1896         ref_transaction_free(transaction);
1897         return ret;
1898 }
1899
1900 int ref_transaction_commit(struct ref_transaction *transaction,
1901                            struct strbuf *err)
1902 {
1903         struct ref_store *refs = transaction->ref_store;
1904         int ret;
1905
1906         switch (transaction->state) {
1907         case REF_TRANSACTION_OPEN:
1908                 /* Need to prepare first. */
1909                 ret = ref_transaction_prepare(transaction, err);
1910                 if (ret)
1911                         return ret;
1912                 break;
1913         case REF_TRANSACTION_PREPARED:
1914                 /* Fall through to finish. */
1915                 break;
1916         case REF_TRANSACTION_CLOSED:
1917                 BUG("commit called on a closed reference transaction");
1918                 break;
1919         default:
1920                 BUG("unexpected reference transaction state");
1921                 break;
1922         }
1923
1924         return refs->be->transaction_finish(refs, transaction, err);
1925 }
1926
1927 int refs_verify_refname_available(struct ref_store *refs,
1928                                   const char *refname,
1929                                   const struct string_list *extras,
1930                                   const struct string_list *skip,
1931                                   struct strbuf *err)
1932 {
1933         const char *slash;
1934         const char *extra_refname;
1935         struct strbuf dirname = STRBUF_INIT;
1936         struct strbuf referent = STRBUF_INIT;
1937         struct object_id oid;
1938         unsigned int type;
1939         struct ref_iterator *iter;
1940         int ok;
1941         int ret = -1;
1942
1943         /*
1944          * For the sake of comments in this function, suppose that
1945          * refname is "refs/foo/bar".
1946          */
1947
1948         assert(err);
1949
1950         strbuf_grow(&dirname, strlen(refname) + 1);
1951         for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
1952                 /* Expand dirname to the new prefix, not including the trailing slash: */
1953                 strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
1954
1955                 /*
1956                  * We are still at a leading dir of the refname (e.g.,
1957                  * "refs/foo"; if there is a reference with that name,
1958                  * it is a conflict, *unless* it is in skip.
1959                  */
1960                 if (skip && string_list_has_string(skip, dirname.buf))
1961                         continue;
1962
1963                 if (!refs_read_raw_ref(refs, dirname.buf, &oid, &referent, &type)) {
1964                         strbuf_addf(err, "'%s' exists; cannot create '%s'",
1965                                     dirname.buf, refname);
1966                         goto cleanup;
1967                 }
1968
1969                 if (extras && string_list_has_string(extras, dirname.buf)) {
1970                         strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
1971                                     refname, dirname.buf);
1972                         goto cleanup;
1973                 }
1974         }
1975
1976         /*
1977          * We are at the leaf of our refname (e.g., "refs/foo/bar").
1978          * There is no point in searching for a reference with that
1979          * name, because a refname isn't considered to conflict with
1980          * itself. But we still need to check for references whose
1981          * names are in the "refs/foo/bar/" namespace, because they
1982          * *do* conflict.
1983          */
1984         strbuf_addstr(&dirname, refname + dirname.len);
1985         strbuf_addch(&dirname, '/');
1986
1987         iter = refs_ref_iterator_begin(refs, dirname.buf, 0,
1988                                        DO_FOR_EACH_INCLUDE_BROKEN);
1989         while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
1990                 if (skip &&
1991                     string_list_has_string(skip, iter->refname))
1992                         continue;
1993
1994                 strbuf_addf(err, "'%s' exists; cannot create '%s'",
1995                             iter->refname, refname);
1996                 ref_iterator_abort(iter);
1997                 goto cleanup;
1998         }
1999
2000         if (ok != ITER_DONE)
2001                 BUG("error while iterating over references");
2002
2003         extra_refname = find_descendant_ref(dirname.buf, extras, skip);
2004         if (extra_refname)
2005                 strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
2006                             refname, extra_refname);
2007         else
2008                 ret = 0;
2009
2010 cleanup:
2011         strbuf_release(&referent);
2012         strbuf_release(&dirname);
2013         return ret;
2014 }
2015
2016 int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2017 {
2018         struct ref_iterator *iter;
2019
2020         iter = refs->be->reflog_iterator_begin(refs);
2021
2022         return do_for_each_ref_iterator(iter, fn, cb_data);
2023 }
2024
2025 int for_each_reflog(each_ref_fn fn, void *cb_data)
2026 {
2027         return refs_for_each_reflog(get_main_ref_store(the_repository), fn, cb_data);
2028 }
2029
2030 int refs_for_each_reflog_ent_reverse(struct ref_store *refs,
2031                                      const char *refname,
2032                                      each_reflog_ent_fn fn,
2033                                      void *cb_data)
2034 {
2035         return refs->be->for_each_reflog_ent_reverse(refs, refname,
2036                                                      fn, cb_data);
2037 }
2038
2039 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
2040                                 void *cb_data)
2041 {
2042         return refs_for_each_reflog_ent_reverse(get_main_ref_store(the_repository),
2043                                                 refname, fn, cb_data);
2044 }
2045
2046 int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname,
2047                              each_reflog_ent_fn fn, void *cb_data)
2048 {
2049         return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
2050 }
2051
2052 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
2053                         void *cb_data)
2054 {
2055         return refs_for_each_reflog_ent(get_main_ref_store(the_repository), refname,
2056                                         fn, cb_data);
2057 }
2058
2059 int refs_reflog_exists(struct ref_store *refs, const char *refname)
2060 {
2061         return refs->be->reflog_exists(refs, refname);
2062 }
2063
2064 int reflog_exists(const char *refname)
2065 {
2066         return refs_reflog_exists(get_main_ref_store(the_repository), refname);
2067 }
2068
2069 int refs_create_reflog(struct ref_store *refs, const char *refname,
2070                        int force_create, struct strbuf *err)
2071 {
2072         return refs->be->create_reflog(refs, refname, force_create, err);
2073 }
2074
2075 int safe_create_reflog(const char *refname, int force_create,
2076                        struct strbuf *err)
2077 {
2078         return refs_create_reflog(get_main_ref_store(the_repository), refname,
2079                                   force_create, err);
2080 }
2081
2082 int refs_delete_reflog(struct ref_store *refs, const char *refname)
2083 {
2084         return refs->be->delete_reflog(refs, refname);
2085 }
2086
2087 int delete_reflog(const char *refname)
2088 {
2089         return refs_delete_reflog(get_main_ref_store(the_repository), refname);
2090 }
2091
2092 int refs_reflog_expire(struct ref_store *refs,
2093                        const char *refname, const struct object_id *oid,
2094                        unsigned int flags,
2095                        reflog_expiry_prepare_fn prepare_fn,
2096                        reflog_expiry_should_prune_fn should_prune_fn,
2097                        reflog_expiry_cleanup_fn cleanup_fn,
2098                        void *policy_cb_data)
2099 {
2100         return refs->be->reflog_expire(refs, refname, oid, flags,
2101                                        prepare_fn, should_prune_fn,
2102                                        cleanup_fn, policy_cb_data);
2103 }
2104
2105 int reflog_expire(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_reflog_expire(get_main_ref_store(the_repository),
2113                                   refname, oid, flags,
2114                                   prepare_fn, should_prune_fn,
2115                                   cleanup_fn, policy_cb_data);
2116 }
2117
2118 int initial_ref_transaction_commit(struct ref_transaction *transaction,
2119                                    struct strbuf *err)
2120 {
2121         struct ref_store *refs = transaction->ref_store;
2122
2123         return refs->be->initial_transaction_commit(refs, transaction, err);
2124 }
2125
2126 int refs_delete_refs(struct ref_store *refs, const char *msg,
2127                      struct string_list *refnames, unsigned int flags)
2128 {
2129         return refs->be->delete_refs(refs, msg, refnames, flags);
2130 }
2131
2132 int delete_refs(const char *msg, struct string_list *refnames,
2133                 unsigned int flags)
2134 {
2135         return refs_delete_refs(get_main_ref_store(the_repository), msg, refnames, flags);
2136 }
2137
2138 int refs_rename_ref(struct ref_store *refs, const char *oldref,
2139                     const char *newref, const char *logmsg)
2140 {
2141         return refs->be->rename_ref(refs, oldref, newref, logmsg);
2142 }
2143
2144 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
2145 {
2146         return refs_rename_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2147 }
2148
2149 int refs_copy_existing_ref(struct ref_store *refs, const char *oldref,
2150                     const char *newref, const char *logmsg)
2151 {
2152         return refs->be->copy_ref(refs, oldref, newref, logmsg);
2153 }
2154
2155 int copy_existing_ref(const char *oldref, const char *newref, const char *logmsg)
2156 {
2157         return refs_copy_existing_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2158 }