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

   1 /*
   2  * The backend-independent part of the reference module.
   3  */
   4
   5 #include "cache.h"
   6 #include "config.h"
   7 #include "hashmap.h"
   8 #include "lockfile.h"
   9 #include "iterator.h"
  10 #include "refs.h"
  11 #include "refs/refs-internal.h"
  12 #include "object-store.h"
  13 #include "object.h"
  14 #include "tag.h"
  15 #include "submodule.h"
  16 #include "worktree.h"
  17 #include "argv-array.h"
  18 #include "repository.h"
  19
  20 /*
  21  * List of all available backends
  22  */
  23 static struct ref_storage_be *refs_backends = &refs_be_files;
  24
  25 static struct ref_storage_be *find_ref_storage_backend(const char *name)
  26 {
  27         struct ref_storage_be *be;
  28         for (be = refs_backends; be; be = be->next)
  29                 if (!strcmp(be->name, name))
  30                         return be;
  31         return NULL;
  32 }
  33
  34 int ref_storage_backend_exists(const char *name)
  35 {
  36         return find_ref_storage_backend(name) != NULL;
  37 }
  38
  39 /*
  40  * How to handle various characters in refnames:
  41  * 0: An acceptable character for refs
  42  * 1: End-of-component
  43  * 2: ., look for a preceding . to reject .. in refs
  44  * 3: {, look for a preceding @ to reject @{ in refs
  45  * 4: A bad character: ASCII control characters, and
  46  *    ":", "?", "[", "\", "^", "~", SP, or TAB
  47  * 5: *, reject unless REFNAME_REFSPEC_PATTERN is set
  48  */
  49 static unsigned char refname_disposition[256] = {
  50         1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
  51         4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
  52         4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 2, 1,
  53         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4,
  54         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  55         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 4, 0,
  56         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  57         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 4
  58 };
  59
  60 /*
  61  * Try to read one refname component from the front of refname.
  62  * Return the length of the component found, or -1 if the component is
  63  * not legal.  It is legal if it is something reasonable to have under
  64  * ".git/refs/"; We do not like it if:
  65  *
  66  * - it begins with ".", or
  67  * - it has double dots "..", or
  68  * - it has ASCII control characters, or
  69  * - it has ":", "?", "[", "\", "^", "~", SP, or TAB anywhere, or
  70  * - it has "*" anywhere unless REFNAME_REFSPEC_PATTERN is set, or
  71  * - it ends with a "/", or
  72  * - it ends with ".lock", or
  73  * - it contains a "@{" portion
  74  *
  75  * When sanitized is not NULL, instead of rejecting the input refname
  76  * as an error, try to come up with a usable replacement for the input
  77  * refname in it.
  78  */
  79 static int check_refname_component(const char *refname, int *flags,
  80                                    struct strbuf *sanitized)
  81 {
  82         const char *cp;
  83         char last = '\0';
  84         size_t component_start = 0; /* garbage - not a reasonable initial value */
  85
  86         if (sanitized)
  87                 component_start = sanitized->len;
  88
  89         for (cp = refname; ; cp++) {
  90                 int ch = *cp & 255;
  91                 unsigned char disp = refname_disposition[ch];
  92
  93                 if (sanitized && disp != 1)
  94                         strbuf_addch(sanitized, ch);
  95
  96                 switch (disp) {
  97                 case 1:
  98                         goto out;
  99                 case 2:
 100                         if (last == '.') { /* Refname contains "..". */
 101                                 if (sanitized)
 102                                         /* collapse ".." to single "." */
 103                                         strbuf_setlen(sanitized, sanitized->len - 1);
 104                                 else
 105                                         return -1;
 106                         }
 107                         break;
 108                 case 3:
 109                         if (last == '@') { /* Refname contains "@{". */
 110                                 if (sanitized)
 111                                         sanitized->buf[sanitized->len-1] = '-';
 112                                 else
 113                                         return -1;
 114                         }
 115                         break;
 116                 case 4:
 117                         /* forbidden char */
 118                         if (sanitized)
 119                                 sanitized->buf[sanitized->len-1] = '-';
 120                         else
 121                                 return -1;
 122                         break;
 123                 case 5:
 124                         if (!(*flags & REFNAME_REFSPEC_PATTERN)) {
 125                                 /* refspec can't be a pattern */
 126                                 if (sanitized)
 127                                         sanitized->buf[sanitized->len-1] = '-';
 128                                 else
 129                                         return -1;
 130                         }
 131
 132                         /*
 133                          * Unset the pattern flag so that we only accept
 134                          * a single asterisk for one side of refspec.
 135                          */
 136                         *flags &= ~ REFNAME_REFSPEC_PATTERN;
 137                         break;
 138                 }
 139                 last = ch;
 140         }
 141 out:
 142         if (cp == refname)
 143                 return 0; /* Component has zero length. */
 144
 145         if (refname[0] == '.') { /* Component starts with '.'. */
 146                 if (sanitized)
 147                         sanitized->buf[component_start] = '-';
 148                 else
 149                         return -1;
 150         }
 151         if (cp - refname >= LOCK_SUFFIX_LEN &&
 152             !memcmp(cp - LOCK_SUFFIX_LEN, LOCK_SUFFIX, LOCK_SUFFIX_LEN)) {
 153                 if (!sanitized)
 154                         return -1;
 155                 /* Refname ends with ".lock". */
 156                 while (strbuf_strip_suffix(sanitized, LOCK_SUFFIX)) {
 157                         /* try again in case we have .lock.lock */
 158                 }
 159         }
 160         return cp - refname;
 161 }
 162
 163 static int check_or_sanitize_refname(const char *refname, int flags,
 164                                      struct strbuf *sanitized)
 165 {
 166         int component_len, component_count = 0;
 167
 168         if (!strcmp(refname, "@")) {
 169                 /* Refname is a single character '@'. */
 170                 if (sanitized)
 171                         strbuf_addch(sanitized, '-');
 172                 else
 173                         return -1;
 174         }
 175
 176         while (1) {
 177                 if (sanitized && sanitized->len)
 178                         strbuf_complete(sanitized, '/');
 179
 180                 /* We are at the start of a path component. */
 181                 component_len = check_refname_component(refname, &flags,
 182                                                         sanitized);
 183                 if (sanitized && component_len == 0)
 184                         ; /* OK, omit empty component */
 185                 else if (component_len <= 0)
 186                         return -1;
 187
 188                 component_count++;
 189                 if (refname[component_len] == '\0')
 190                         break;
 191                 /* Skip to next component. */
 192                 refname += component_len + 1;
 193         }
 194
 195         if (refname[component_len - 1] == '.') {
 196                 /* Refname ends with '.'. */
 197                 if (sanitized)
 198                         ; /* omit ending dot */
 199                 else
 200                         return -1;
 201         }
 202         if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
 203                 return -1; /* Refname has only one component. */
 204         return 0;
 205 }
 206
 207 int check_refname_format(const char *refname, int flags)
 208 {
 209         return check_or_sanitize_refname(refname, flags, NULL);
 210 }
 211
 212 void sanitize_refname_component(const char *refname, struct strbuf *out)
 213 {
 214         if (check_or_sanitize_refname(refname, REFNAME_ALLOW_ONELEVEL, out))
 215                 BUG("sanitizing refname '%s' check returned error", refname);
 216 }
 217
 218 int refname_is_safe(const char *refname)
 219 {
 220         const char *rest;
 221
 222         if (skip_prefix(refname, "refs/", &rest)) {
 223                 char *buf;
 224                 int result;
 225                 size_t restlen = strlen(rest);
 226
 227                 /* rest must not be empty, or start or end with "/" */
 228                 if (!restlen || *rest == '/' || rest[restlen - 1] == '/')
 229                         return 0;
 230
 231                 /*
 232                  * Does the refname try to escape refs/?
 233                  * For example: refs/foo/../bar is safe but refs/foo/../../bar
 234                  * is not.
 235                  */
 236                 buf = xmallocz(restlen);
 237                 result = !normalize_path_copy(buf, rest) && !strcmp(buf, rest);
 238                 free(buf);
 239                 return result;
 240         }
 241
 242         do {
 243                 if (!isupper(*refname) && *refname != '_')
 244                         return 0;
 245                 refname++;
 246         } while (*refname);
 247         return 1;
 248 }
 249
 250 /*
 251  * Return true if refname, which has the specified oid and flags, can
 252  * be resolved to an object in the database. If the referred-to object
 253  * does not exist, emit a warning and return false.
 254  */
 255 int ref_resolves_to_object(const char *refname,
 256                            const struct object_id *oid,
 257                            unsigned int flags)
 258 {
 259         if (flags & REF_ISBROKEN)
 260                 return 0;
 261         if (!has_object_file(oid)) {
 262                 error(_("%s does not point to a valid object!"), refname);
 263                 return 0;
 264         }
 265         return 1;
 266 }
 267
 268 char *refs_resolve_refdup(struct ref_store *refs,
 269                           const char *refname, int resolve_flags,
 270                           struct object_id *oid, int *flags)
 271 {
 272         const char *result;
 273
 274         result = refs_resolve_ref_unsafe(refs, refname, resolve_flags,
 275                                          oid, flags);
 276         return xstrdup_or_null(result);
 277 }
 278
 279 char *resolve_refdup(const char *refname, int resolve_flags,
 280                      struct object_id *oid, int *flags)
 281 {
 282         return refs_resolve_refdup(get_main_ref_store(the_repository),
 283                                    refname, resolve_flags,
 284                                    oid, flags);
 285 }
 286
 287 /* The argument to filter_refs */
 288 struct ref_filter {
 289         const char *pattern;
 290         const char *prefix;
 291         each_ref_fn *fn;
 292         void *cb_data;
 293 };
 294
 295 int refs_read_ref_full(struct ref_store *refs, const char *refname,
 296                        int resolve_flags, struct object_id *oid, int *flags)
 297 {
 298         if (refs_resolve_ref_unsafe(refs, refname, resolve_flags, oid, flags))
 299                 return 0;
 300         return -1;
 301 }
 302
 303 int read_ref_full(const char *refname, int resolve_flags, struct object_id *oid, int *flags)
 304 {
 305         return refs_read_ref_full(get_main_ref_store(the_repository), refname,
 306                                   resolve_flags, oid, flags);
 307 }
 308
 309 int read_ref(const char *refname, struct object_id *oid)
 310 {
 311         return read_ref_full(refname, RESOLVE_REF_READING, oid, NULL);
 312 }
 313
 314 static int refs_ref_exists(struct ref_store *refs, const char *refname)
 315 {
 316         return !!refs_resolve_ref_unsafe(refs, refname, RESOLVE_REF_READING, NULL, NULL);
 317 }
 318
 319 int ref_exists(const char *refname)
 320 {
 321         return refs_ref_exists(get_main_ref_store(the_repository), refname);
 322 }
 323
 324 static int filter_refs(const char *refname, const struct object_id *oid,
 325                            int flags, void *data)
 326 {
 327         struct ref_filter *filter = (struct ref_filter *)data;
 328
 329         if (wildmatch(filter->pattern, refname, 0))
 330                 return 0;
 331         if (filter->prefix)
 332                 skip_prefix(refname, filter->prefix, &refname);
 333         return filter->fn(refname, oid, flags, filter->cb_data);
 334 }
 335
 336 enum peel_status peel_object(const struct object_id *name, struct object_id *oid)
 337 {
 338         struct object *o = lookup_unknown_object(name);
 339
 340         if (o->type == OBJ_NONE) {
 341                 int type = oid_object_info(the_repository, name, NULL);
 342                 if (type < 0 || !object_as_type(the_repository, o, type, 0))
 343                         return PEEL_INVALID;
 344         }
 345
 346         if (o->type != OBJ_TAG)
 347                 return PEEL_NON_TAG;
 348
 349         o = deref_tag_noverify(o);
 350         if (!o)
 351                 return PEEL_INVALID;
 352
 353         oidcpy(oid, &o->oid);
 354         return PEEL_PEELED;
 355 }
 356
 357 struct warn_if_dangling_data {
 358         FILE *fp;
 359         const char *refname;
 360         const struct string_list *refnames;
 361         const char *msg_fmt;
 362 };
 363
 364 static int warn_if_dangling_symref(const char *refname, const struct object_id *oid,
 365                                    int flags, void *cb_data)
 366 {
 367         struct warn_if_dangling_data *d = cb_data;
 368         const char *resolves_to;
 369
 370         if (!(flags & REF_ISSYMREF))
 371                 return 0;
 372
 373         resolves_to = resolve_ref_unsafe(refname, 0, NULL, NULL);
 374         if (!resolves_to
 375             || (d->refname
 376                 ? strcmp(resolves_to, d->refname)
 377                 : !string_list_has_string(d->refnames, resolves_to))) {
 378                 return 0;
 379         }
 380
 381         fprintf(d->fp, d->msg_fmt, refname);
 382         fputc('\n', d->fp);
 383         return 0;
 384 }
 385
 386 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
 387 {
 388         struct warn_if_dangling_data data;
 389
 390         data.fp = fp;
 391         data.refname = refname;
 392         data.refnames = NULL;
 393         data.msg_fmt = msg_fmt;
 394         for_each_rawref(warn_if_dangling_symref, &data);
 395 }
 396
 397 void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames)
 398 {
 399         struct warn_if_dangling_data data;
 400
 401         data.fp = fp;
 402         data.refname = NULL;
 403         data.refnames = refnames;
 404         data.msg_fmt = msg_fmt;
 405         for_each_rawref(warn_if_dangling_symref, &data);
 406 }
 407
 408 int refs_for_each_tag_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
 409 {
 410         return refs_for_each_ref_in(refs, "refs/tags/", fn, cb_data);
 411 }
 412
 413 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
 414 {
 415         return refs_for_each_tag_ref(get_main_ref_store(the_repository), fn, cb_data);
 416 }
 417
 418 int refs_for_each_branch_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
 419 {
 420         return refs_for_each_ref_in(refs, "refs/heads/", fn, cb_data);
 421 }
 422
 423 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
 424 {
 425         return refs_for_each_branch_ref(get_main_ref_store(the_repository), fn, cb_data);
 426 }
 427
 428 int refs_for_each_remote_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
 429 {
 430         return refs_for_each_ref_in(refs, "refs/remotes/", fn, cb_data);
 431 }
 432
 433 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
 434 {
 435         return refs_for_each_remote_ref(get_main_ref_store(the_repository), fn, cb_data);
 436 }
 437
 438 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
 439 {
 440         struct strbuf buf = STRBUF_INIT;
 441         int ret = 0;
 442         struct object_id oid;
 443         int flag;
 444
 445         strbuf_addf(&buf, "%sHEAD", get_git_namespace());
 446         if (!read_ref_full(buf.buf, RESOLVE_REF_READING, &oid, &flag))
 447                 ret = fn(buf.buf, &oid, flag, cb_data);
 448         strbuf_release(&buf);
 449
 450         return ret;
 451 }
 452
 453 void normalize_glob_ref(struct string_list_item *item, const char *prefix,
 454                         const char *pattern)
 455 {
 456         struct strbuf normalized_pattern = STRBUF_INIT;
 457
 458         if (*pattern == '/')
 459                 BUG("pattern must not start with '/'");
 460
 461         if (prefix) {
 462                 strbuf_addstr(&normalized_pattern, prefix);
 463         }
 464         else if (!starts_with(pattern, "refs/"))
 465                 strbuf_addstr(&normalized_pattern, "refs/");
 466         strbuf_addstr(&normalized_pattern, pattern);
 467         strbuf_strip_suffix(&normalized_pattern, "/");
 468
 469         item->string = strbuf_detach(&normalized_pattern, NULL);
 470         item->util = has_glob_specials(pattern) ? NULL : item->string;
 471         strbuf_release(&normalized_pattern);
 472 }
 473
 474 int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
 475         const char *prefix, void *cb_data)
 476 {
 477         struct strbuf real_pattern = STRBUF_INIT;
 478         struct ref_filter filter;
 479         int ret;
 480
 481         if (!prefix && !starts_with(pattern, "refs/"))
 482                 strbuf_addstr(&real_pattern, "refs/");
 483         else if (prefix)
 484                 strbuf_addstr(&real_pattern, prefix);
 485         strbuf_addstr(&real_pattern, pattern);
 486
 487         if (!has_glob_specials(pattern)) {
 488                 /* Append implied '/' '*' if not present. */
 489                 strbuf_complete(&real_pattern, '/');
 490                 /* No need to check for '*', there is none. */
 491                 strbuf_addch(&real_pattern, '*');
 492         }
 493
 494         filter.pattern = real_pattern.buf;
 495         filter.prefix = prefix;
 496         filter.fn = fn;
 497         filter.cb_data = cb_data;
 498         ret = for_each_ref(filter_refs, &filter);
 499
 500         strbuf_release(&real_pattern);
 501         return ret;
 502 }
 503
 504 int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
 505 {
 506         return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
 507 }
 508
 509 const char *prettify_refname(const char *name)
 510 {
 511         if (skip_prefix(name, "refs/heads/", &name) ||
 512             skip_prefix(name, "refs/tags/", &name) ||
 513             skip_prefix(name, "refs/remotes/", &name))
 514                 ; /* nothing */
 515         return name;
 516 }
 517
 518 static const char *ref_rev_parse_rules[] = {
 519         "%.*s",
 520         "refs/%.*s",
 521         "refs/tags/%.*s",
 522         "refs/heads/%.*s",
 523         "refs/remotes/%.*s",
 524         "refs/remotes/%.*s/HEAD",
 525         NULL
 526 };
 527
 528 #define NUM_REV_PARSE_RULES (ARRAY_SIZE(ref_rev_parse_rules) - 1)
 529
 530 /*
 531  * Is it possible that the caller meant full_name with abbrev_name?
 532  * If so return a non-zero value to signal "yes"; the magnitude of
 533  * the returned value gives the precedence used for disambiguation.
 534  *
 535  * If abbrev_name cannot mean full_name, return 0.
 536  */
 537 int refname_match(const char *abbrev_name, const char *full_name)
 538 {
 539         const char **p;
 540         const int abbrev_name_len = strlen(abbrev_name);
 541         const int num_rules = NUM_REV_PARSE_RULES;
 542
 543         for (p = ref_rev_parse_rules; *p; p++)
 544                 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name)))
 545                         return &ref_rev_parse_rules[num_rules] - p;
 546
 547         return 0;
 548 }
 549
 550 /*
 551  * Given a 'prefix' expand it by the rules in 'ref_rev_parse_rules' and add
 552  * the results to 'prefixes'
 553  */
 554 void expand_ref_prefix(struct argv_array *prefixes, const char *prefix)
 555 {
 556         const char **p;
 557         int len = strlen(prefix);
 558
 559         for (p = ref_rev_parse_rules; *p; p++)
 560                 argv_array_pushf(prefixes, *p, len, prefix);
 561 }
 562
 563 /*
 564  * *string and *len will only be substituted, and *string returned (for
 565  * later free()ing) if the string passed in is a magic short-hand form
 566  * to name a branch.
 567  */
 568 static char *substitute_branch_name(struct repository *r,
 569                                     const char **string, int *len)
 570 {
 571         struct strbuf buf = STRBUF_INIT;
 572         int ret = repo_interpret_branch_name(r, *string, *len, &buf, 0);
 573
 574         if (ret == *len) {
 575                 size_t size;
 576                 *string = strbuf_detach(&buf, &size);
 577                 *len = size;
 578                 return (char *)*string;
 579         }
 580
 581         return NULL;
 582 }
 583
 584 int repo_dwim_ref(struct repository *r, const char *str, int len,
 585                   struct object_id *oid, char **ref)
 586 {
 587         char *last_branch = substitute_branch_name(r, &str, &len);
 588         int   refs_found  = expand_ref(r, str, len, oid, ref);
 589         free(last_branch);
 590         return refs_found;
 591 }
 592
 593 int dwim_ref(const char *str, int len, struct object_id *oid, char **ref)
 594 {
 595         return repo_dwim_ref(the_repository, str, len, oid, ref);
 596 }
 597
 598 int expand_ref(struct repository *repo, const char *str, int len,
 599                struct object_id *oid, char **ref)
 600 {
 601         const char **p, *r;
 602         int refs_found = 0;
 603         struct strbuf fullref = STRBUF_INIT;
 604
 605         *ref = NULL;
 606         for (p = ref_rev_parse_rules; *p; p++) {
 607                 struct object_id oid_from_ref;
 608                 struct object_id *this_result;
 609                 int flag;
 610
 611                 this_result = refs_found ? &oid_from_ref : oid;
 612                 strbuf_reset(&fullref);
 613                 strbuf_addf(&fullref, *p, len, str);
 614                 r = refs_resolve_ref_unsafe(get_main_ref_store(repo),
 615                                             fullref.buf, RESOLVE_REF_READING,
 616                                             this_result, &flag);
 617                 if (r) {
 618                         if (!refs_found++)
 619                                 *ref = xstrdup(r);
 620                         if (!warn_ambiguous_refs)
 621                                 break;
 622                 } else if ((flag & REF_ISSYMREF) && strcmp(fullref.buf, "HEAD")) {
 623                         warning(_("ignoring dangling symref %s"), fullref.buf);
 624                 } else if ((flag & REF_ISBROKEN) && strchr(fullref.buf, '/')) {
 625                         warning(_("ignoring broken ref %s"), fullref.buf);
 626                 }
 627         }
 628         strbuf_release(&fullref);
 629         return refs_found;
 630 }
 631
 632 int repo_dwim_log(struct repository *r, const char *str, int len,
 633                   struct object_id *oid, char **log)
 634 {
 635         struct ref_store *refs = get_main_ref_store(r);
 636         char *last_branch = substitute_branch_name(r, &str, &len);
 637         const char **p;
 638         int logs_found = 0;
 639         struct strbuf path = STRBUF_INIT;
 640
 641         *log = NULL;
 642         for (p = ref_rev_parse_rules; *p; p++) {
 643                 struct object_id hash;
 644                 const char *ref, *it;
 645
 646                 strbuf_reset(&path);
 647                 strbuf_addf(&path, *p, len, str);
 648                 ref = refs_resolve_ref_unsafe(refs, path.buf,
 649                                               RESOLVE_REF_READING,
 650                                               &hash, NULL);
 651                 if (!ref)
 652                         continue;
 653                 if (refs_reflog_exists(refs, path.buf))
 654                         it = path.buf;
 655                 else if (strcmp(ref, path.buf) &&
 656                          refs_reflog_exists(refs, ref))
 657                         it = ref;
 658                 else
 659                         continue;
 660                 if (!logs_found++) {
 661                         *log = xstrdup(it);
 662                         oidcpy(oid, &hash);
 663                 }
 664                 if (!warn_ambiguous_refs)
 665                         break;
 666         }
 667         strbuf_release(&path);
 668         free(last_branch);
 669         return logs_found;
 670 }
 671
 672 int dwim_log(const char *str, int len, struct object_id *oid, char **log)
 673 {
 674         return repo_dwim_log(the_repository, str, len, oid, log);
 675 }
 676
 677 static int is_per_worktree_ref(const char *refname)
 678 {
 679         return !strcmp(refname, "HEAD") ||
 680                 starts_with(refname, "refs/worktree/") ||
 681                 starts_with(refname, "refs/bisect/") ||
 682                 starts_with(refname, "refs/rewritten/");
 683 }
 684
 685 static int is_pseudoref_syntax(const char *refname)
 686 {
 687         const char *c;
 688
 689         for (c = refname; *c; c++) {
 690                 if (!isupper(*c) && *c != '-' && *c != '_')
 691                         return 0;
 692         }
 693
 694         return 1;
 695 }
 696
 697 static int is_main_pseudoref_syntax(const char *refname)
 698 {
 699         return skip_prefix(refname, "main-worktree/", &refname) &&
 700                 *refname &&
 701                 is_pseudoref_syntax(refname);
 702 }
 703
 704 static int is_other_pseudoref_syntax(const char *refname)
 705 {
 706         if (!skip_prefix(refname, "worktrees/", &refname))
 707                 return 0;
 708         refname = strchr(refname, '/');
 709         if (!refname || !refname[1])
 710                 return 0;
 711         return is_pseudoref_syntax(refname + 1);
 712 }
 713
 714 enum ref_type ref_type(const char *refname)
 715 {
 716         if (is_per_worktree_ref(refname))
 717                 return REF_TYPE_PER_WORKTREE;
 718         if (is_pseudoref_syntax(refname))
 719                 return REF_TYPE_PSEUDOREF;
 720         if (is_main_pseudoref_syntax(refname))
 721                 return REF_TYPE_MAIN_PSEUDOREF;
 722         if (is_other_pseudoref_syntax(refname))
 723                 return REF_TYPE_OTHER_PSEUDOREF;
 724         return REF_TYPE_NORMAL;
 725 }
 726
 727 long get_files_ref_lock_timeout_ms(void)
 728 {
 729         static int configured = 0;
 730
 731         /* The default timeout is 100 ms: */
 732         static int timeout_ms = 100;
 733
 734         if (!configured) {
 735                 git_config_get_int("core.filesreflocktimeout", &timeout_ms);
 736                 configured = 1;
 737         }
 738
 739         return timeout_ms;
 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         transaction = ref_store_transaction_begin(refs, &err);
 751         if (!transaction ||
 752             ref_transaction_delete(transaction, refname, old_oid,
 753                                    flags, msg, &err) ||
 754             ref_transaction_commit(transaction, &err)) {
 755                 error("%s", err.buf);
 756                 ref_transaction_free(transaction);
 757                 strbuf_release(&err);
 758                 return 1;
 759         }
 760         ref_transaction_free(transaction);
 761         strbuf_release(&err);
 762         return 0;
 763 }
 764
 765 int delete_ref(const char *msg, const char *refname,
 766                const struct object_id *old_oid, unsigned int flags)
 767 {
 768         return refs_delete_ref(get_main_ref_store(the_repository), msg, refname,
 769                                old_oid, flags);
 770 }
 771
 772 static void copy_reflog_msg(struct strbuf *sb, const char *msg)
 773 {
 774         char c;
 775         int wasspace = 1;
 776
 777         strbuf_addch(sb, '\t');
 778         while ((c = *msg++)) {
 779                 if (wasspace && isspace(c))
 780                         continue;
 781                 wasspace = isspace(c);
 782                 if (wasspace)
 783                         c = ' ';
 784                 strbuf_addch(sb, c);
 785         }
 786         strbuf_rtrim(sb);
 787 }
 788
 789 static char *normalize_reflog_message(const char *msg)
 790 {
 791         struct strbuf sb = STRBUF_INIT;
 792
 793         if (msg && *msg)
 794                 copy_reflog_msg(&sb, msg);
 795         return strbuf_detach(&sb, NULL);
 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 (!oideq(&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 (!oideq(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(struct ref_store *refs, const char *refname,
 905                 unsigned int flags, timestamp_t at_time, int cnt,
 906                 struct object_id *oid, char **msg,
 907                 timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
 908 {
 909         struct read_ref_at_cb cb;
 910
 911         memset(&cb, 0, sizeof(cb));
 912         cb.refname = refname;
 913         cb.at_time = at_time;
 914         cb.cnt = cnt;
 915         cb.msg = msg;
 916         cb.cutoff_time = cutoff_time;
 917         cb.cutoff_tz = cutoff_tz;
 918         cb.cutoff_cnt = cutoff_cnt;
 919         cb.oid = oid;
 920
 921         refs_for_each_reflog_ent_reverse(refs, refname, read_ref_at_ent, &cb);
 922
 923         if (!cb.reccnt) {
 924                 if (flags & GET_OID_QUIETLY)
 925                         exit(128);
 926                 else
 927                         die(_("log for %s is empty"), refname);
 928         }
 929         if (cb.found_it)
 930                 return 0;
 931
 932         refs_for_each_reflog_ent(refs, refname, read_ref_at_ent_oldest, &cb);
 933
 934         return 1;
 935 }
 936
 937 struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs,
 938                                                     struct strbuf *err)
 939 {
 940         struct ref_transaction *tr;
 941         assert(err);
 942
 943         tr = xcalloc(1, sizeof(struct ref_transaction));
 944         tr->ref_store = refs;
 945         return tr;
 946 }
 947
 948 struct ref_transaction *ref_transaction_begin(struct strbuf *err)
 949 {
 950         return ref_store_transaction_begin(get_main_ref_store(the_repository), err);
 951 }
 952
 953 void ref_transaction_free(struct ref_transaction *transaction)
 954 {
 955         size_t i;
 956
 957         if (!transaction)
 958                 return;
 959
 960         switch (transaction->state) {
 961         case REF_TRANSACTION_OPEN:
 962         case REF_TRANSACTION_CLOSED:
 963                 /* OK */
 964                 break;
 965         case REF_TRANSACTION_PREPARED:
 966                 BUG("free called on a prepared reference transaction");
 967                 break;
 968         default:
 969                 BUG("unexpected reference transaction state");
 970                 break;
 971         }
 972
 973         for (i = 0; i < transaction->nr; i++) {
 974                 free(transaction->updates[i]->msg);
 975                 free(transaction->updates[i]);
 976         }
 977         free(transaction->updates);
 978         free(transaction);
 979 }
 980
 981 struct ref_update *ref_transaction_add_update(
 982                 struct ref_transaction *transaction,
 983                 const char *refname, unsigned int flags,
 984                 const struct object_id *new_oid,
 985                 const struct object_id *old_oid,
 986                 const char *msg)
 987 {
 988         struct ref_update *update;
 989
 990         if (transaction->state != REF_TRANSACTION_OPEN)
 991                 BUG("update called for transaction that is not open");
 992
 993         FLEX_ALLOC_STR(update, refname, refname);
 994         ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
 995         transaction->updates[transaction->nr++] = update;
 996
 997         update->flags = flags;
 998
 999         if (flags & REF_HAVE_NEW)
1000                 oidcpy(&update->new_oid, new_oid);
1001         if (flags & REF_HAVE_OLD)
1002                 oidcpy(&update->old_oid, old_oid);
1003         update->msg = normalize_reflog_message(msg);
1004         return update;
1005 }
1006
1007 int ref_transaction_update(struct ref_transaction *transaction,
1008                            const char *refname,
1009                            const struct object_id *new_oid,
1010                            const struct object_id *old_oid,
1011                            unsigned int flags, const char *msg,
1012                            struct strbuf *err)
1013 {
1014         assert(err);
1015
1016         if ((new_oid && !is_null_oid(new_oid)) ?
1017             check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
1018             !refname_is_safe(refname)) {
1019                 strbuf_addf(err, _("refusing to update ref with bad name '%s'"),
1020                             refname);
1021                 return -1;
1022         }
1023
1024         if (flags & ~REF_TRANSACTION_UPDATE_ALLOWED_FLAGS)
1025                 BUG("illegal flags 0x%x passed to ref_transaction_update()", flags);
1026
1027         flags |= (new_oid ? REF_HAVE_NEW : 0) | (old_oid ? REF_HAVE_OLD : 0);
1028
1029         ref_transaction_add_update(transaction, refname, flags,
1030                                    new_oid, old_oid, msg);
1031         return 0;
1032 }
1033
1034 int ref_transaction_create(struct ref_transaction *transaction,
1035                            const char *refname,
1036                            const struct object_id *new_oid,
1037                            unsigned int flags, const char *msg,
1038                            struct strbuf *err)
1039 {
1040         if (!new_oid || is_null_oid(new_oid))
1041                 BUG("create called without valid new_oid");
1042         return ref_transaction_update(transaction, refname, new_oid,
1043                                       &null_oid, flags, msg, err);
1044 }
1045
1046 int ref_transaction_delete(struct ref_transaction *transaction,
1047                            const char *refname,
1048                            const struct object_id *old_oid,
1049                            unsigned int flags, const char *msg,
1050                            struct strbuf *err)
1051 {
1052         if (old_oid && is_null_oid(old_oid))
1053                 BUG("delete called with old_oid set to zeros");
1054         return ref_transaction_update(transaction, refname,
1055                                       &null_oid, old_oid,
1056                                       flags, msg, err);
1057 }
1058
1059 int ref_transaction_verify(struct ref_transaction *transaction,
1060                            const char *refname,
1061                            const struct object_id *old_oid,
1062                            unsigned int flags,
1063                            struct strbuf *err)
1064 {
1065         if (!old_oid)
1066                 BUG("verify called with old_oid set to NULL");
1067         return ref_transaction_update(transaction, refname,
1068                                       NULL, old_oid,
1069                                       flags, NULL, err);
1070 }
1071
1072 int refs_update_ref(struct ref_store *refs, const char *msg,
1073                     const char *refname, const struct object_id *new_oid,
1074                     const struct object_id *old_oid, unsigned int flags,
1075                     enum action_on_err onerr)
1076 {
1077         struct ref_transaction *t = NULL;
1078         struct strbuf err = STRBUF_INIT;
1079         int ret = 0;
1080
1081         t = ref_store_transaction_begin(refs, &err);
1082         if (!t ||
1083             ref_transaction_update(t, refname, new_oid, old_oid, flags, msg,
1084                                    &err) ||
1085             ref_transaction_commit(t, &err)) {
1086                 ret = 1;
1087                 ref_transaction_free(t);
1088         }
1089         if (ret) {
1090                 const char *str = _("update_ref failed for ref '%s': %s");
1091
1092                 switch (onerr) {
1093                 case UPDATE_REFS_MSG_ON_ERR:
1094                         error(str, refname, err.buf);
1095                         break;
1096                 case UPDATE_REFS_DIE_ON_ERR:
1097                         die(str, refname, err.buf);
1098                         break;
1099                 case UPDATE_REFS_QUIET_ON_ERR:
1100                         break;
1101                 }
1102                 strbuf_release(&err);
1103                 return 1;
1104         }
1105         strbuf_release(&err);
1106         if (t)
1107                 ref_transaction_free(t);
1108         return 0;
1109 }
1110
1111 int update_ref(const char *msg, const char *refname,
1112                const struct object_id *new_oid,
1113                const struct object_id *old_oid,
1114                unsigned int flags, enum action_on_err onerr)
1115 {
1116         return refs_update_ref(get_main_ref_store(the_repository), msg, refname, new_oid,
1117                                old_oid, flags, onerr);
1118 }
1119
1120 char *refs_shorten_unambiguous_ref(struct ref_store *refs,
1121                                    const char *refname, int strict)
1122 {
1123         int i;
1124         static char **scanf_fmts;
1125         static int nr_rules;
1126         char *short_name;
1127         struct strbuf resolved_buf = STRBUF_INIT;
1128
1129         if (!nr_rules) {
1130                 /*
1131                  * Pre-generate scanf formats from ref_rev_parse_rules[].
1132                  * Generate a format suitable for scanf from a
1133                  * ref_rev_parse_rules rule by interpolating "%s" at the
1134                  * location of the "%.*s".
1135                  */
1136                 size_t total_len = 0;
1137                 size_t offset = 0;
1138
1139                 /* the rule list is NULL terminated, count them first */
1140                 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
1141                         /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
1142                         total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
1143
1144                 scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len));
1145
1146                 offset = 0;
1147                 for (i = 0; i < nr_rules; i++) {
1148                         assert(offset < total_len);
1149                         scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
1150                         offset += xsnprintf(scanf_fmts[i], total_len - offset,
1151                                             ref_rev_parse_rules[i], 2, "%s") + 1;
1152                 }
1153         }
1154
1155         /* bail out if there are no rules */
1156         if (!nr_rules)
1157                 return xstrdup(refname);
1158
1159         /* buffer for scanf result, at most refname must fit */
1160         short_name = xstrdup(refname);
1161
1162         /* skip first rule, it will always match */
1163         for (i = nr_rules - 1; i > 0 ; --i) {
1164                 int j;
1165                 int rules_to_fail = i;
1166                 int short_name_len;
1167
1168                 if (1 != sscanf(refname, scanf_fmts[i], short_name))
1169                         continue;
1170
1171                 short_name_len = strlen(short_name);
1172
1173                 /*
1174                  * in strict mode, all (except the matched one) rules
1175                  * must fail to resolve to a valid non-ambiguous ref
1176                  */
1177                 if (strict)
1178                         rules_to_fail = nr_rules;
1179
1180                 /*
1181                  * check if the short name resolves to a valid ref,
1182                  * but use only rules prior to the matched one
1183                  */
1184                 for (j = 0; j < rules_to_fail; j++) {
1185                         const char *rule = ref_rev_parse_rules[j];
1186
1187                         /* skip matched rule */
1188                         if (i == j)
1189                                 continue;
1190
1191                         /*
1192                          * the short name is ambiguous, if it resolves
1193                          * (with this previous rule) to a valid ref
1194                          * read_ref() returns 0 on success
1195                          */
1196                         strbuf_reset(&resolved_buf);
1197                         strbuf_addf(&resolved_buf, rule,
1198                                     short_name_len, short_name);
1199                         if (refs_ref_exists(refs, resolved_buf.buf))
1200                                 break;
1201                 }
1202
1203                 /*
1204                  * short name is non-ambiguous if all previous rules
1205                  * haven't resolved to a valid ref
1206                  */
1207                 if (j == rules_to_fail) {
1208                         strbuf_release(&resolved_buf);
1209                         return short_name;
1210                 }
1211         }
1212
1213         strbuf_release(&resolved_buf);
1214         free(short_name);
1215         return xstrdup(refname);
1216 }
1217
1218 char *shorten_unambiguous_ref(const char *refname, int strict)
1219 {
1220         return refs_shorten_unambiguous_ref(get_main_ref_store(the_repository),
1221                                             refname, strict);
1222 }
1223
1224 static struct string_list *hide_refs;
1225
1226 int parse_hide_refs_config(const char *var, const char *value, const char *section)
1227 {
1228         const char *key;
1229         if (!strcmp("transfer.hiderefs", var) ||
1230             (!parse_config_key(var, section, NULL, NULL, &key) &&
1231              !strcmp(key, "hiderefs"))) {
1232                 char *ref;
1233                 int len;
1234
1235                 if (!value)
1236                         return config_error_nonbool(var);
1237                 ref = xstrdup(value);
1238                 len = strlen(ref);
1239                 while (len && ref[len - 1] == '/')
1240                         ref[--len] = '\0';
1241                 if (!hide_refs) {
1242                         hide_refs = xcalloc(1, sizeof(*hide_refs));
1243                         hide_refs->strdup_strings = 1;
1244                 }
1245                 string_list_append(hide_refs, ref);
1246         }
1247         return 0;
1248 }
1249
1250 int ref_is_hidden(const char *refname, const char *refname_full)
1251 {
1252         int i;
1253
1254         if (!hide_refs)
1255                 return 0;
1256         for (i = hide_refs->nr - 1; i >= 0; i--) {
1257                 const char *match = hide_refs->items[i].string;
1258                 const char *subject;
1259                 int neg = 0;
1260                 const char *p;
1261
1262                 if (*match == '!') {
1263                         neg = 1;
1264                         match++;
1265                 }
1266
1267                 if (*match == '^') {
1268                         subject = refname_full;
1269                         match++;
1270                 } else {
1271                         subject = refname;
1272                 }
1273
1274                 /* refname can be NULL when namespaces are used. */
1275                 if (subject &&
1276                     skip_prefix(subject, match, &p) &&
1277                     (!*p || *p == '/'))
1278                         return !neg;
1279         }
1280         return 0;
1281 }
1282
1283 const char *find_descendant_ref(const char *dirname,
1284                                 const struct string_list *extras,
1285                                 const struct string_list *skip)
1286 {
1287         int pos;
1288
1289         if (!extras)
1290                 return NULL;
1291
1292         /*
1293          * Look at the place where dirname would be inserted into
1294          * extras. If there is an entry at that position that starts
1295          * with dirname (remember, dirname includes the trailing
1296          * slash) and is not in skip, then we have a conflict.
1297          */
1298         for (pos = string_list_find_insert_index(extras, dirname, 0);
1299              pos < extras->nr; pos++) {
1300                 const char *extra_refname = extras->items[pos].string;
1301
1302                 if (!starts_with(extra_refname, dirname))
1303                         break;
1304
1305                 if (!skip || !string_list_has_string(skip, extra_refname))
1306                         return extra_refname;
1307         }
1308         return NULL;
1309 }
1310
1311 int refs_rename_ref_available(struct ref_store *refs,
1312                               const char *old_refname,
1313                               const char *new_refname)
1314 {
1315         struct string_list skip = STRING_LIST_INIT_NODUP;
1316         struct strbuf err = STRBUF_INIT;
1317         int ok;
1318
1319         string_list_insert(&skip, old_refname);
1320         ok = !refs_verify_refname_available(refs, new_refname,
1321                                             NULL, &skip, &err);
1322         if (!ok)
1323                 error("%s", err.buf);
1324
1325         string_list_clear(&skip, 0);
1326         strbuf_release(&err);
1327         return ok;
1328 }
1329
1330 int refs_head_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1331 {
1332         struct object_id oid;
1333         int flag;
1334
1335         if (!refs_read_ref_full(refs, "HEAD", RESOLVE_REF_READING,
1336                                 &oid, &flag))
1337                 return fn("HEAD", &oid, flag, cb_data);
1338
1339         return 0;
1340 }
1341
1342 int head_ref(each_ref_fn fn, void *cb_data)
1343 {
1344         return refs_head_ref(get_main_ref_store(the_repository), fn, cb_data);
1345 }
1346
1347 struct ref_iterator *refs_ref_iterator_begin(
1348                 struct ref_store *refs,
1349                 const char *prefix, int trim, int flags)
1350 {
1351         struct ref_iterator *iter;
1352
1353         if (ref_paranoia < 0)
1354                 ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
1355         if (ref_paranoia)
1356                 flags |= DO_FOR_EACH_INCLUDE_BROKEN;
1357
1358         iter = refs->be->iterator_begin(refs, prefix, flags);
1359
1360         /*
1361          * `iterator_begin()` already takes care of prefix, but we
1362          * might need to do some trimming:
1363          */
1364         if (trim)
1365                 iter = prefix_ref_iterator_begin(iter, "", trim);
1366
1367         /* Sanity check for subclasses: */
1368         if (!iter->ordered)
1369                 BUG("reference iterator is not ordered");
1370
1371         return iter;
1372 }
1373
1374 /*
1375  * Call fn for each reference in the specified submodule for which the
1376  * refname begins with prefix. If trim is non-zero, then trim that
1377  * many characters off the beginning of each refname before passing
1378  * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
1379  * include broken references in the iteration. If fn ever returns a
1380  * non-zero value, stop the iteration and return that value;
1381  * otherwise, return 0.
1382  */
1383 static int do_for_each_repo_ref(struct repository *r, const char *prefix,
1384                                 each_repo_ref_fn fn, int trim, int flags,
1385                                 void *cb_data)
1386 {
1387         struct ref_iterator *iter;
1388         struct ref_store *refs = get_main_ref_store(r);
1389
1390         if (!refs)
1391                 return 0;
1392
1393         iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1394
1395         return do_for_each_repo_ref_iterator(r, iter, fn, cb_data);
1396 }
1397
1398 struct do_for_each_ref_help {
1399         each_ref_fn *fn;
1400         void *cb_data;
1401 };
1402
1403 static int do_for_each_ref_helper(struct repository *r,
1404                                   const char *refname,
1405                                   const struct object_id *oid,
1406                                   int flags,
1407                                   void *cb_data)
1408 {
1409         struct do_for_each_ref_help *hp = cb_data;
1410
1411         return hp->fn(refname, oid, flags, hp->cb_data);
1412 }
1413
1414 static int do_for_each_ref(struct ref_store *refs, const char *prefix,
1415                            each_ref_fn fn, int trim, int flags, void *cb_data)
1416 {
1417         struct ref_iterator *iter;
1418         struct do_for_each_ref_help hp = { fn, cb_data };
1419
1420         if (!refs)
1421                 return 0;
1422
1423         iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
1424
1425         return do_for_each_repo_ref_iterator(the_repository, iter,
1426                                         do_for_each_ref_helper, &hp);
1427 }
1428
1429 int refs_for_each_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1430 {
1431         return do_for_each_ref(refs, "", fn, 0, 0, cb_data);
1432 }
1433
1434 int for_each_ref(each_ref_fn fn, void *cb_data)
1435 {
1436         return refs_for_each_ref(get_main_ref_store(the_repository), fn, cb_data);
1437 }
1438
1439 int refs_for_each_ref_in(struct ref_store *refs, const char *prefix,
1440                          each_ref_fn fn, void *cb_data)
1441 {
1442         return do_for_each_ref(refs, prefix, fn, strlen(prefix), 0, cb_data);
1443 }
1444
1445 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
1446 {
1447         return refs_for_each_ref_in(get_main_ref_store(the_repository), prefix, fn, cb_data);
1448 }
1449
1450 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
1451 {
1452         unsigned int flag = 0;
1453
1454         if (broken)
1455                 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1456         return do_for_each_ref(get_main_ref_store(the_repository),
1457                                prefix, fn, 0, flag, cb_data);
1458 }
1459
1460 int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix,
1461                              each_ref_fn fn, void *cb_data,
1462                              unsigned int broken)
1463 {
1464         unsigned int flag = 0;
1465
1466         if (broken)
1467                 flag = DO_FOR_EACH_INCLUDE_BROKEN;
1468         return do_for_each_ref(refs, prefix, fn, 0, flag, cb_data);
1469 }
1470
1471 int for_each_replace_ref(struct repository *r, each_repo_ref_fn fn, void *cb_data)
1472 {
1473         return do_for_each_repo_ref(r, git_replace_ref_base, fn,
1474                                     strlen(git_replace_ref_base),
1475                                     DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1476 }
1477
1478 int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
1479 {
1480         struct strbuf buf = STRBUF_INIT;
1481         int ret;
1482         strbuf_addf(&buf, "%srefs/", get_git_namespace());
1483         ret = do_for_each_ref(get_main_ref_store(the_repository),
1484                               buf.buf, fn, 0, 0, cb_data);
1485         strbuf_release(&buf);
1486         return ret;
1487 }
1488
1489 int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
1490 {
1491         return do_for_each_ref(refs, "", fn, 0,
1492                                DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
1493 }
1494
1495 int for_each_rawref(each_ref_fn fn, void *cb_data)
1496 {
1497         return refs_for_each_rawref(get_main_ref_store(the_repository), fn, cb_data);
1498 }
1499
1500 int refs_read_raw_ref(struct ref_store *ref_store,
1501                       const char *refname, struct object_id *oid,
1502                       struct strbuf *referent, unsigned int *type)
1503 {
1504         return ref_store->be->read_raw_ref(ref_store, refname, oid, referent, type);
1505 }
1506
1507 /* This function needs to return a meaningful errno on failure */
1508 const char *refs_resolve_ref_unsafe(struct ref_store *refs,
1509                                     const char *refname,
1510                                     int resolve_flags,
1511                                     struct object_id *oid, int *flags)
1512 {
1513         static struct strbuf sb_refname = STRBUF_INIT;
1514         struct object_id unused_oid;
1515         int unused_flags;
1516         int symref_count;
1517
1518         if (!oid)
1519                 oid = &unused_oid;
1520         if (!flags)
1521                 flags = &unused_flags;
1522
1523         *flags = 0;
1524
1525         if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1526                 if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1527                     !refname_is_safe(refname)) {
1528                         errno = EINVAL;
1529                         return NULL;
1530                 }
1531
1532                 /*
1533                  * dwim_ref() uses REF_ISBROKEN to distinguish between
1534                  * missing refs and refs that were present but invalid,
1535                  * to complain about the latter to stderr.
1536                  *
1537                  * We don't know whether the ref exists, so don't set
1538                  * REF_ISBROKEN yet.
1539                  */
1540                 *flags |= REF_BAD_NAME;
1541         }
1542
1543         for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
1544                 unsigned int read_flags = 0;
1545
1546                 if (refs_read_raw_ref(refs, refname,
1547                                       oid, &sb_refname, &read_flags)) {
1548                         *flags |= read_flags;
1549
1550                         /* In reading mode, refs must eventually resolve */
1551                         if (resolve_flags & RESOLVE_REF_READING)
1552                                 return NULL;
1553
1554                         /*
1555                          * Otherwise a missing ref is OK. But the files backend
1556                          * may show errors besides ENOENT if there are
1557                          * similarly-named refs.
1558                          */
1559                         if (errno != ENOENT &&
1560                             errno != EISDIR &&
1561                             errno != ENOTDIR)
1562                                 return NULL;
1563
1564                         oidclr(oid);
1565                         if (*flags & REF_BAD_NAME)
1566                                 *flags |= REF_ISBROKEN;
1567                         return refname;
1568                 }
1569
1570                 *flags |= read_flags;
1571
1572                 if (!(read_flags & REF_ISSYMREF)) {
1573                         if (*flags & REF_BAD_NAME) {
1574                                 oidclr(oid);
1575                                 *flags |= REF_ISBROKEN;
1576                         }
1577                         return refname;
1578                 }
1579
1580                 refname = sb_refname.buf;
1581                 if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
1582                         oidclr(oid);
1583                         return refname;
1584                 }
1585                 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
1586                         if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
1587                             !refname_is_safe(refname)) {
1588                                 errno = EINVAL;
1589                                 return NULL;
1590                         }
1591
1592                         *flags |= REF_ISBROKEN | REF_BAD_NAME;
1593                 }
1594         }
1595
1596         errno = ELOOP;
1597         return NULL;
1598 }
1599
1600 /* backend functions */
1601 int refs_init_db(struct strbuf *err)
1602 {
1603         struct ref_store *refs = get_main_ref_store(the_repository);
1604
1605         return refs->be->init_db(refs, err);
1606 }
1607
1608 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
1609                                struct object_id *oid, int *flags)
1610 {
1611         return refs_resolve_ref_unsafe(get_main_ref_store(the_repository), refname,
1612                                        resolve_flags, oid, flags);
1613 }
1614
1615 int resolve_gitlink_ref(const char *submodule, const char *refname,
1616                         struct object_id *oid)
1617 {
1618         struct ref_store *refs;
1619         int flags;
1620
1621         refs = get_submodule_ref_store(submodule);
1622
1623         if (!refs)
1624                 return -1;
1625
1626         if (!refs_resolve_ref_unsafe(refs, refname, 0, oid, &flags) ||
1627             is_null_oid(oid))
1628                 return -1;
1629         return 0;
1630 }
1631
1632 struct ref_store_hash_entry
1633 {
1634         struct hashmap_entry ent;
1635
1636         struct ref_store *refs;
1637
1638         /* NUL-terminated identifier of the ref store: */
1639         char name[FLEX_ARRAY];
1640 };
1641
1642 static int ref_store_hash_cmp(const void *unused_cmp_data,
1643                               const struct hashmap_entry *eptr,
1644                               const struct hashmap_entry *entry_or_key,
1645                               const void *keydata)
1646 {
1647         const struct ref_store_hash_entry *e1, *e2;
1648         const char *name;
1649
1650         e1 = container_of(eptr, const struct ref_store_hash_entry, ent);
1651         e2 = container_of(entry_or_key, const struct ref_store_hash_entry, ent);
1652         name = keydata ? keydata : e2->name;
1653
1654         return strcmp(e1->name, name);
1655 }
1656
1657 static struct ref_store_hash_entry *alloc_ref_store_hash_entry(
1658                 const char *name, struct ref_store *refs)
1659 {
1660         struct ref_store_hash_entry *entry;
1661
1662         FLEX_ALLOC_STR(entry, name, name);
1663         hashmap_entry_init(&entry->ent, strhash(name));
1664         entry->refs = refs;
1665         return entry;
1666 }
1667
1668 /* A hashmap of ref_stores, stored by submodule name: */
1669 static struct hashmap submodule_ref_stores;
1670
1671 /* A hashmap of ref_stores, stored by worktree id: */
1672 static struct hashmap worktree_ref_stores;
1673
1674 /*
1675  * Look up a ref store by name. If that ref_store hasn't been
1676  * registered yet, return NULL.
1677  */
1678 static struct ref_store *lookup_ref_store_map(struct hashmap *map,
1679                                               const char *name)
1680 {
1681         struct ref_store_hash_entry *entry;
1682         unsigned int hash;
1683
1684         if (!map->tablesize)
1685                 /* It's initialized on demand in register_ref_store(). */
1686                 return NULL;
1687
1688         hash = strhash(name);
1689         entry = hashmap_get_entry_from_hash(map, hash, name,
1690                                         struct ref_store_hash_entry, ent);
1691         return entry ? entry->refs : NULL;
1692 }
1693
1694 /*
1695  * Create, record, and return a ref_store instance for the specified
1696  * gitdir.
1697  */
1698 static struct ref_store *ref_store_init(const char *gitdir,
1699                                         unsigned int flags)
1700 {
1701         const char *be_name = "files";
1702         struct ref_storage_be *be = find_ref_storage_backend(be_name);
1703         struct ref_store *refs;
1704
1705         if (!be)
1706                 BUG("reference backend %s is unknown", be_name);
1707
1708         refs = be->init(gitdir, flags);
1709         return refs;
1710 }
1711
1712 struct ref_store *get_main_ref_store(struct repository *r)
1713 {
1714         if (r->refs_private)
1715                 return r->refs_private;
1716
1717         if (!r->gitdir)
1718                 BUG("attempting to get main_ref_store outside of repository");
1719
1720         r->refs_private = ref_store_init(r->gitdir, REF_STORE_ALL_CAPS);
1721         return r->refs_private;
1722 }
1723
1724 /*
1725  * Associate a ref store with a name. It is a fatal error to call this
1726  * function twice for the same name.
1727  */
1728 static void register_ref_store_map(struct hashmap *map,
1729                                    const char *type,
1730                                    struct ref_store *refs,
1731                                    const char *name)
1732 {
1733         struct ref_store_hash_entry *entry;
1734
1735         if (!map->tablesize)
1736                 hashmap_init(map, ref_store_hash_cmp, NULL, 0);
1737
1738         entry = alloc_ref_store_hash_entry(name, refs);
1739         if (hashmap_put(map, &entry->ent))
1740                 BUG("%s ref_store '%s' initialized twice", type, name);
1741 }
1742
1743 struct ref_store *get_submodule_ref_store(const char *submodule)
1744 {
1745         struct strbuf submodule_sb = STRBUF_INIT;
1746         struct ref_store *refs;
1747         char *to_free = NULL;
1748         size_t len;
1749
1750         if (!submodule)
1751                 return NULL;
1752
1753         len = strlen(submodule);
1754         while (len && is_dir_sep(submodule[len - 1]))
1755                 len--;
1756         if (!len)
1757                 return NULL;
1758
1759         if (submodule[len])
1760                 /* We need to strip off one or more trailing slashes */
1761                 submodule = to_free = xmemdupz(submodule, len);
1762
1763         refs = lookup_ref_store_map(&submodule_ref_stores, submodule);
1764         if (refs)
1765                 goto done;
1766
1767         strbuf_addstr(&submodule_sb, submodule);
1768         if (!is_nonbare_repository_dir(&submodule_sb))
1769                 goto done;
1770
1771         if (submodule_to_gitdir(&submodule_sb, submodule))
1772                 goto done;
1773
1774         /* assume that add_submodule_odb() has been called */
1775         refs = ref_store_init(submodule_sb.buf,
1776                               REF_STORE_READ | REF_STORE_ODB);
1777         register_ref_store_map(&submodule_ref_stores, "submodule",
1778                                refs, submodule);
1779
1780 done:
1781         strbuf_release(&submodule_sb);
1782         free(to_free);
1783
1784         return refs;
1785 }
1786
1787 struct ref_store *get_worktree_ref_store(const struct worktree *wt)
1788 {
1789         struct ref_store *refs;
1790         const char *id;
1791
1792         if (wt->is_current)
1793                 return get_main_ref_store(the_repository);
1794
1795         id = wt->id ? wt->id : "/";
1796         refs = lookup_ref_store_map(&worktree_ref_stores, id);
1797         if (refs)
1798                 return refs;
1799
1800         if (wt->id)
1801                 refs = ref_store_init(git_common_path("worktrees/%s", wt->id),
1802                                       REF_STORE_ALL_CAPS);
1803         else
1804                 refs = ref_store_init(get_git_common_dir(),
1805                                       REF_STORE_ALL_CAPS);
1806
1807         if (refs)
1808                 register_ref_store_map(&worktree_ref_stores, "worktree",
1809                                        refs, id);
1810         return refs;
1811 }
1812
1813 void base_ref_store_init(struct ref_store *refs,
1814                          const struct ref_storage_be *be)
1815 {
1816         refs->be = be;
1817 }
1818
1819 /* backend functions */
1820 int refs_pack_refs(struct ref_store *refs, unsigned int flags)
1821 {
1822         return refs->be->pack_refs(refs, flags);
1823 }
1824
1825 int refs_peel_ref(struct ref_store *refs, const char *refname,
1826                   struct object_id *oid)
1827 {
1828         int flag;
1829         struct object_id base;
1830
1831         if (current_ref_iter && current_ref_iter->refname == refname) {
1832                 struct object_id peeled;
1833
1834                 if (ref_iterator_peel(current_ref_iter, &peeled))
1835                         return -1;
1836                 oidcpy(oid, &peeled);
1837                 return 0;
1838         }
1839
1840         if (refs_read_ref_full(refs, refname,
1841                                RESOLVE_REF_READING, &base, &flag))
1842                 return -1;
1843
1844         return peel_object(&base, oid);
1845 }
1846
1847 int peel_ref(const char *refname, struct object_id *oid)
1848 {
1849         return refs_peel_ref(get_main_ref_store(the_repository), refname, oid);
1850 }
1851
1852 int refs_create_symref(struct ref_store *refs,
1853                        const char *ref_target,
1854                        const char *refs_heads_master,
1855                        const char *logmsg)
1856 {
1857         char *msg;
1858         int retval;
1859
1860         msg = normalize_reflog_message(logmsg);
1861         retval = refs->be->create_symref(refs, ref_target, refs_heads_master,
1862                                          msg);
1863         free(msg);
1864         return retval;
1865 }
1866
1867 int create_symref(const char *ref_target, const char *refs_heads_master,
1868                   const char *logmsg)
1869 {
1870         return refs_create_symref(get_main_ref_store(the_repository), ref_target,
1871                                   refs_heads_master, logmsg);
1872 }
1873
1874 int ref_update_reject_duplicates(struct string_list *refnames,
1875                                  struct strbuf *err)
1876 {
1877         size_t i, n = refnames->nr;
1878
1879         assert(err);
1880
1881         for (i = 1; i < n; i++) {
1882                 int cmp = strcmp(refnames->items[i - 1].string,
1883                                  refnames->items[i].string);
1884
1885                 if (!cmp) {
1886                         strbuf_addf(err,
1887                                     _("multiple updates for ref '%s' not allowed"),
1888                                     refnames->items[i].string);
1889                         return 1;
1890                 } else if (cmp > 0) {
1891                         BUG("ref_update_reject_duplicates() received unsorted list");
1892                 }
1893         }
1894         return 0;
1895 }
1896
1897 int ref_transaction_prepare(struct ref_transaction *transaction,
1898                             struct strbuf *err)
1899 {
1900         struct ref_store *refs = transaction->ref_store;
1901
1902         switch (transaction->state) {
1903         case REF_TRANSACTION_OPEN:
1904                 /* Good. */
1905                 break;
1906         case REF_TRANSACTION_PREPARED:
1907                 BUG("prepare called twice on reference transaction");
1908                 break;
1909         case REF_TRANSACTION_CLOSED:
1910                 BUG("prepare called on a closed reference transaction");
1911                 break;
1912         default:
1913                 BUG("unexpected reference transaction state");
1914                 break;
1915         }
1916
1917         if (getenv(GIT_QUARANTINE_ENVIRONMENT)) {
1918                 strbuf_addstr(err,
1919                               _("ref updates forbidden inside quarantine environment"));
1920                 return -1;
1921         }
1922
1923         return refs->be->transaction_prepare(refs, transaction, err);
1924 }
1925
1926 int ref_transaction_abort(struct ref_transaction *transaction,
1927                           struct strbuf *err)
1928 {
1929         struct ref_store *refs = transaction->ref_store;
1930         int ret = 0;
1931
1932         switch (transaction->state) {
1933         case REF_TRANSACTION_OPEN:
1934                 /* No need to abort explicitly. */
1935                 break;
1936         case REF_TRANSACTION_PREPARED:
1937                 ret = refs->be->transaction_abort(refs, transaction, err);
1938                 break;
1939         case REF_TRANSACTION_CLOSED:
1940                 BUG("abort called on a closed reference transaction");
1941                 break;
1942         default:
1943                 BUG("unexpected reference transaction state");
1944                 break;
1945         }
1946
1947         ref_transaction_free(transaction);
1948         return ret;
1949 }
1950
1951 int ref_transaction_commit(struct ref_transaction *transaction,
1952                            struct strbuf *err)
1953 {
1954         struct ref_store *refs = transaction->ref_store;
1955         int ret;
1956
1957         switch (transaction->state) {
1958         case REF_TRANSACTION_OPEN:
1959                 /* Need to prepare first. */
1960                 ret = ref_transaction_prepare(transaction, err);
1961                 if (ret)
1962                         return ret;
1963                 break;
1964         case REF_TRANSACTION_PREPARED:
1965                 /* Fall through to finish. */
1966                 break;
1967         case REF_TRANSACTION_CLOSED:
1968                 BUG("commit called on a closed reference transaction");
1969                 break;
1970         default:
1971                 BUG("unexpected reference transaction state");
1972                 break;
1973         }
1974
1975         return refs->be->transaction_finish(refs, transaction, err);
1976 }
1977
1978 int refs_verify_refname_available(struct ref_store *refs,
1979                                   const char *refname,
1980                                   const struct string_list *extras,
1981                                   const struct string_list *skip,
1982                                   struct strbuf *err)
1983 {
1984         const char *slash;
1985         const char *extra_refname;
1986         struct strbuf dirname = STRBUF_INIT;
1987         struct strbuf referent = STRBUF_INIT;
1988         struct object_id oid;
1989         unsigned int type;
1990         struct ref_iterator *iter;
1991         int ok;
1992         int ret = -1;
1993
1994         /*
1995          * For the sake of comments in this function, suppose that
1996          * refname is "refs/foo/bar".
1997          */
1998
1999         assert(err);
2000
2001         strbuf_grow(&dirname, strlen(refname) + 1);
2002         for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
2003                 /* Expand dirname to the new prefix, not including the trailing slash: */
2004                 strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
2005
2006                 /*
2007                  * We are still at a leading dir of the refname (e.g.,
2008                  * "refs/foo"; if there is a reference with that name,
2009                  * it is a conflict, *unless* it is in skip.
2010                  */
2011                 if (skip && string_list_has_string(skip, dirname.buf))
2012                         continue;
2013
2014                 if (!refs_read_raw_ref(refs, dirname.buf, &oid, &referent, &type)) {
2015                         strbuf_addf(err, _("'%s' exists; cannot create '%s'"),
2016                                     dirname.buf, refname);
2017                         goto cleanup;
2018                 }
2019
2020                 if (extras && string_list_has_string(extras, dirname.buf)) {
2021                         strbuf_addf(err, _("cannot process '%s' and '%s' at the same time"),
2022                                     refname, dirname.buf);
2023                         goto cleanup;
2024                 }
2025         }
2026
2027         /*
2028          * We are at the leaf of our refname (e.g., "refs/foo/bar").
2029          * There is no point in searching for a reference with that
2030          * name, because a refname isn't considered to conflict with
2031          * itself. But we still need to check for references whose
2032          * names are in the "refs/foo/bar/" namespace, because they
2033          * *do* conflict.
2034          */
2035         strbuf_addstr(&dirname, refname + dirname.len);
2036         strbuf_addch(&dirname, '/');
2037
2038         iter = refs_ref_iterator_begin(refs, dirname.buf, 0,
2039                                        DO_FOR_EACH_INCLUDE_BROKEN);
2040         while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
2041                 if (skip &&
2042                     string_list_has_string(skip, iter->refname))
2043                         continue;
2044
2045                 strbuf_addf(err, _("'%s' exists; cannot create '%s'"),
2046                             iter->refname, refname);
2047                 ref_iterator_abort(iter);
2048                 goto cleanup;
2049         }
2050
2051         if (ok != ITER_DONE)
2052                 BUG("error while iterating over references");
2053
2054         extra_refname = find_descendant_ref(dirname.buf, extras, skip);
2055         if (extra_refname)
2056                 strbuf_addf(err, _("cannot process '%s' and '%s' at the same time"),
2057                             refname, extra_refname);
2058         else
2059                 ret = 0;
2060
2061 cleanup:
2062         strbuf_release(&referent);
2063         strbuf_release(&dirname);
2064         return ret;
2065 }
2066
2067 int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)
2068 {
2069         struct ref_iterator *iter;
2070         struct do_for_each_ref_help hp = { fn, cb_data };
2071
2072         iter = refs->be->reflog_iterator_begin(refs);
2073
2074         return do_for_each_repo_ref_iterator(the_repository, iter,
2075                                              do_for_each_ref_helper, &hp);
2076 }
2077
2078 int for_each_reflog(each_ref_fn fn, void *cb_data)
2079 {
2080         return refs_for_each_reflog(get_main_ref_store(the_repository), fn, cb_data);
2081 }
2082
2083 int refs_for_each_reflog_ent_reverse(struct ref_store *refs,
2084                                      const char *refname,
2085                                      each_reflog_ent_fn fn,
2086                                      void *cb_data)
2087 {
2088         return refs->be->for_each_reflog_ent_reverse(refs, refname,
2089                                                      fn, cb_data);
2090 }
2091
2092 int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
2093                                 void *cb_data)
2094 {
2095         return refs_for_each_reflog_ent_reverse(get_main_ref_store(the_repository),
2096                                                 refname, fn, cb_data);
2097 }
2098
2099 int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname,
2100                              each_reflog_ent_fn fn, void *cb_data)
2101 {
2102         return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
2103 }
2104
2105 int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
2106                         void *cb_data)
2107 {
2108         return refs_for_each_reflog_ent(get_main_ref_store(the_repository), refname,
2109                                         fn, cb_data);
2110 }
2111
2112 int refs_reflog_exists(struct ref_store *refs, const char *refname)
2113 {
2114         return refs->be->reflog_exists(refs, refname);
2115 }
2116
2117 int reflog_exists(const char *refname)
2118 {
2119         return refs_reflog_exists(get_main_ref_store(the_repository), refname);
2120 }
2121
2122 int refs_create_reflog(struct ref_store *refs, const char *refname,
2123                        int force_create, struct strbuf *err)
2124 {
2125         return refs->be->create_reflog(refs, refname, force_create, err);
2126 }
2127
2128 int safe_create_reflog(const char *refname, int force_create,
2129                        struct strbuf *err)
2130 {
2131         return refs_create_reflog(get_main_ref_store(the_repository), refname,
2132                                   force_create, err);
2133 }
2134
2135 int refs_delete_reflog(struct ref_store *refs, const char *refname)
2136 {
2137         return refs->be->delete_reflog(refs, refname);
2138 }
2139
2140 int delete_reflog(const char *refname)
2141 {
2142         return refs_delete_reflog(get_main_ref_store(the_repository), refname);
2143 }
2144
2145 int refs_reflog_expire(struct ref_store *refs,
2146                        const char *refname, const struct object_id *oid,
2147                        unsigned int flags,
2148                        reflog_expiry_prepare_fn prepare_fn,
2149                        reflog_expiry_should_prune_fn should_prune_fn,
2150                        reflog_expiry_cleanup_fn cleanup_fn,
2151                        void *policy_cb_data)
2152 {
2153         return refs->be->reflog_expire(refs, refname, oid, flags,
2154                                        prepare_fn, should_prune_fn,
2155                                        cleanup_fn, policy_cb_data);
2156 }
2157
2158 int reflog_expire(const char *refname, const struct object_id *oid,
2159                   unsigned int flags,
2160                   reflog_expiry_prepare_fn prepare_fn,
2161                   reflog_expiry_should_prune_fn should_prune_fn,
2162                   reflog_expiry_cleanup_fn cleanup_fn,
2163                   void *policy_cb_data)
2164 {
2165         return refs_reflog_expire(get_main_ref_store(the_repository),
2166                                   refname, oid, flags,
2167                                   prepare_fn, should_prune_fn,
2168                                   cleanup_fn, policy_cb_data);
2169 }
2170
2171 int initial_ref_transaction_commit(struct ref_transaction *transaction,
2172                                    struct strbuf *err)
2173 {
2174         struct ref_store *refs = transaction->ref_store;
2175
2176         return refs->be->initial_transaction_commit(refs, transaction, err);
2177 }
2178
2179 int refs_delete_refs(struct ref_store *refs, const char *logmsg,
2180                      struct string_list *refnames, unsigned int flags)
2181 {
2182         char *msg;
2183         int retval;
2184
2185         msg = normalize_reflog_message(logmsg);
2186         retval = refs->be->delete_refs(refs, msg, refnames, flags);
2187         free(msg);
2188         return retval;
2189 }
2190
2191 int delete_refs(const char *msg, struct string_list *refnames,
2192                 unsigned int flags)
2193 {
2194         return refs_delete_refs(get_main_ref_store(the_repository), msg, refnames, flags);
2195 }
2196
2197 int refs_rename_ref(struct ref_store *refs, const char *oldref,
2198                     const char *newref, const char *logmsg)
2199 {
2200         char *msg;
2201         int retval;
2202
2203         msg = normalize_reflog_message(logmsg);
2204         retval = refs->be->rename_ref(refs, oldref, newref, msg);
2205         free(msg);
2206         return retval;
2207 }
2208
2209 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
2210 {
2211         return refs_rename_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2212 }
2213
2214 int refs_copy_existing_ref(struct ref_store *refs, const char *oldref,
2215                     const char *newref, const char *logmsg)
2216 {
2217         char *msg;
2218         int retval;
2219
2220         msg = normalize_reflog_message(logmsg);
2221         retval = refs->be->copy_ref(refs, oldref, newref, msg);
2222         free(msg);
2223         return retval;
2224 }
2225
2226 int copy_existing_ref(const char *oldref, const char *newref, const char *logmsg)
2227 {
2228         return refs_copy_existing_ref(get_main_ref_store(the_repository), oldref, newref, logmsg);
2229 }