lib/reference.c

   1 /*
   2  * Copyright (c) 2018, 2019 Stefan Sperling <stsp@openbsd.org>
   3  *
   4  * Permission to use, copy, modify, and distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 #include "got_compat.h"
  18
  19 #include <sys/types.h>
  20 #include <sys/queue.h>
  21 #include <sys/stat.h>
  22
  23 #include <errno.h>
  24 #include <dirent.h>
  25 #include <limits.h>
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <unistd.h>
  30 #include <zlib.h>
  31 #include <time.h>
  32 #include <libgen.h>
  33
  34 #include "got_error.h"
  35 #include "got_object.h"
  36 #include "got_repository.h"
  37 #include "got_reference.h"
  38 #include "got_opentemp.h"
  39 #include "got_path.h"
  40
  41 #include "got_lib_hash.h"
  42 #include "got_lib_delta.h"
  43 #include "got_lib_inflate.h"
  44 #include "got_lib_object.h"
  45 #include "got_lib_object_idset.h"
  46 #include "got_lib_lockfile.h"
  47
  48 #ifndef nitems
  49 #define nitems(_a) (sizeof(_a) / sizeof((_a)[0]))
  50 #endif
  51
  52 #define GOT_REF_HEADS   "heads"
  53 #define GOT_REF_TAGS    "tags"
  54 #define GOT_REF_REMOTES "remotes"
  55
  56 /*
  57  * We do not resolve tags yet, and don't yet care about sorting refs either,
  58  * so packed-refs files we write contain a minimal header which disables all
  59  * packed-refs "traits" supported by Git.
  60  */
  61 #define GOT_PACKED_REFS_HEADER  "# pack-refs with:"
  62
  63 /* A symbolic reference. */
  64 struct got_symref {
  65         char *name;
  66         char *ref;
  67 };
  68
  69 #define GOT_REF_RECURSE_MAX     20
  70
  71 /* A non-symbolic reference (there is no better designation). */
  72 struct got_ref {
  73         char *name;
  74         struct got_object_id id;
  75 };
  76
  77 /* A reference which points to an arbitrary object. */
  78 struct got_reference {
  79         unsigned int flags;
  80 #define GOT_REF_IS_SYMBOLIC     0x01
  81 #define GOT_REF_IS_PACKED       0x02
  82
  83         union {
  84                 struct got_ref ref;
  85                 struct got_symref symref;
  86         } ref;
  87
  88         struct got_lockfile *lf;
  89         time_t mtime;
  90
  91         /* Cached timestamp for got_ref_cmp_by_commit_timestamp_descending() */
  92         time_t committer_time;
  93 };
  94
  95 static const struct got_error *
  96 alloc_ref(struct got_reference **ref, const char *name,
  97     struct got_object_id *id, int flags, time_t mtime)
  98 {
  99         const struct got_error *err = NULL;
 100
 101         *ref = calloc(1, sizeof(**ref));
 102         if (*ref == NULL)
 103                 return got_error_from_errno("calloc");
 104
 105         memcpy(&(*ref)->ref.ref.id, id, sizeof((*ref)->ref.ref.id));
 106         (*ref)->flags = flags;
 107         (*ref)->ref.ref.name = strdup(name);
 108         (*ref)->mtime = mtime;
 109         if ((*ref)->ref.ref.name == NULL) {
 110                 err = got_error_from_errno("strdup");
 111                 got_ref_close(*ref);
 112                 *ref = NULL;
 113         }
 114         return err;
 115 }
 116
 117 static const struct got_error *
 118 alloc_symref(struct got_reference **ref, const char *name,
 119     const char *target_ref, int flags)
 120 {
 121         const struct got_error *err = NULL;
 122
 123         *ref = calloc(1, sizeof(**ref));
 124         if (*ref == NULL)
 125                 return got_error_from_errno("calloc");
 126
 127         (*ref)->flags = GOT_REF_IS_SYMBOLIC | flags;
 128         (*ref)->ref.symref.name = strdup(name);
 129         if ((*ref)->ref.symref.name == NULL) {
 130                 err = got_error_from_errno("strdup");
 131                 got_ref_close(*ref);
 132                 *ref = NULL;
 133                 return err;
 134         }
 135         (*ref)->ref.symref.ref = strdup(target_ref);
 136         if ((*ref)->ref.symref.ref == NULL) {
 137                 err = got_error_from_errno("strdup");
 138                 got_ref_close(*ref);
 139                 *ref = NULL;
 140         }
 141         return err;
 142 }
 143
 144 static const struct got_error *
 145 parse_symref(struct got_reference **ref, const char *name, const char *line)
 146 {
 147         if (line[0] == '\0')
 148                 return got_error(GOT_ERR_BAD_REF_DATA);
 149
 150         return alloc_symref(ref, name, line, 0);
 151 }
 152
 153 static const struct got_error *
 154 parse_ref_line(struct got_reference **ref, const char *name, const char *line,
 155     time_t mtime, enum got_hash_algorithm algo)
 156 {
 157         struct got_object_id id;
 158
 159         if (strncmp(line, "ref: ", 5) == 0) {
 160                 line += 5;
 161                 return parse_symref(ref, name, line);
 162         }
 163
 164         if (!got_parse_object_id(&id, line, algo))
 165                 return got_error(GOT_ERR_BAD_REF_DATA);
 166
 167         return alloc_ref(ref, name, &id, 0, mtime);
 168 }
 169
 170 static const struct got_error *
 171 parse_ref_file(struct got_reference **ref, const char *name,
 172     const char *absname, const char *abspath, int lock,
 173     enum got_hash_algorithm algo)
 174 {
 175         const struct got_error *err = NULL;
 176         FILE *f;
 177         char *line = NULL;
 178         size_t linesize = 0;
 179         ssize_t linelen;
 180         struct got_lockfile *lf = NULL;
 181         struct stat sb;
 182
 183         if (lock) {
 184                 err = got_lockfile_lock(&lf, abspath, -1);
 185                 if (err) {
 186                         if (err->code == GOT_ERR_ERRNO && errno == ENOENT)
 187                                 err = got_error_not_ref(name);
 188                         return err;
 189                 }
 190         }
 191
 192         f = fopen(abspath, "rbe");
 193         if (f == NULL) {
 194                 if (errno != ENOTDIR && errno != ENOENT)
 195                         err = got_error_from_errno2("fopen", abspath);
 196                 else
 197                         err = got_error_not_ref(name);
 198                 if (lock)
 199                         got_lockfile_unlock(lf, -1);
 200                 return err;
 201         }
 202         if (fstat(fileno(f), &sb) == -1) {
 203                 err = got_error_from_errno2("fstat", abspath);
 204                 goto done;
 205         }
 206
 207         linelen = getline(&line, &linesize, f);
 208         if (linelen == -1) {
 209                 if (feof(f))
 210                         err = NULL; /* ignore empty files (could be locks) */
 211                 else {
 212                         if (errno == EISDIR)
 213                                 err = got_error(GOT_ERR_NOT_REF);
 214                         else if (ferror(f))
 215                                 err = got_ferror(f, GOT_ERR_IO);
 216                         else
 217                                 err = got_error_from_errno2("getline", abspath);
 218                 }
 219                 if (lock)
 220                         got_lockfile_unlock(lf, -1);
 221                 goto done;
 222         }
 223         while (linelen > 0 && line[linelen - 1] == '\n') {
 224                 line[linelen - 1] = '\0';
 225                 linelen--;
 226         }
 227
 228         err = parse_ref_line(ref, absname, line, sb.st_mtime, algo);
 229         if (lock) {
 230                 if (err)
 231                         got_lockfile_unlock(lf, -1);
 232                 else {
 233                         if (*ref)
 234                                 (*ref)->lf = lf;
 235                         else
 236                                 got_lockfile_unlock(lf, -1);
 237                 }
 238         }
 239 done:
 240         free(line);
 241         if (fclose(f) == EOF && err == NULL) {
 242                 err = got_error_from_errno("fclose");
 243                 if (*ref) {
 244                         if (lock)
 245                                 got_ref_unlock(*ref);
 246                         got_ref_close(*ref);
 247                         *ref = NULL;
 248                 }
 249         }
 250         return err;
 251 }
 252
 253 static int
 254 is_well_known_ref(const char *refname)
 255 {
 256         return (strcmp(refname, GOT_REF_HEAD) == 0 ||
 257             strcmp(refname, GOT_REF_ORIG_HEAD) == 0 ||
 258             strcmp(refname, GOT_REF_MERGE_HEAD) == 0 ||
 259             strcmp(refname, GOT_REF_FETCH_HEAD) == 0);
 260 }
 261
 262 static char *
 263 get_refs_dir_path(struct got_repository *repo, const char *refname)
 264 {
 265         if (is_well_known_ref(refname) || strncmp(refname, "refs/", 5) == 0)
 266                 return strdup(got_repo_get_path_git_dir(repo));
 267
 268         return got_repo_get_path_refs(repo);
 269 }
 270
 271 const struct got_error *
 272 got_ref_alloc(struct got_reference **ref, const char *name,
 273     struct got_object_id *id)
 274 {
 275         if (!got_ref_name_is_valid(name))
 276                 return got_error_path(name, GOT_ERR_BAD_REF_NAME);
 277
 278         return alloc_ref(ref, name, id, 0, 0);
 279 }
 280
 281 const struct got_error *
 282 got_ref_alloc_symref(struct got_reference **ref, const char *name,
 283         struct got_reference *target_ref)
 284 {
 285         if (!got_ref_name_is_valid(name))
 286                 return got_error_path(name, GOT_ERR_BAD_REF_NAME);
 287
 288         return alloc_symref(ref, name, got_ref_get_name(target_ref), 0);
 289 }
 290
 291 static const struct got_error *
 292 parse_packed_ref_line(struct got_reference **ref, const char *abs_refname,
 293     const char *line, time_t mtime, enum got_hash_algorithm algo)
 294 {
 295         struct got_object_id id;
 296         const char *name;
 297
 298         *ref = NULL;
 299
 300         if (line[0] == '#' || line[0] == '^')
 301                 return NULL;
 302
 303         if (!got_parse_object_id(&id, line, algo))
 304                 return got_error(GOT_ERR_BAD_REF_DATA);
 305
 306         if (abs_refname) {
 307                 if (strcmp(line + SHA1_DIGEST_STRING_LENGTH, abs_refname) != 0)
 308                         return NULL;
 309                 name = abs_refname;
 310         } else
 311                 name = line + SHA1_DIGEST_STRING_LENGTH;
 312
 313         return alloc_ref(ref, name, &id, GOT_REF_IS_PACKED, mtime);
 314 }
 315
 316 static const struct got_error *
 317 open_packed_ref(struct got_reference **ref, FILE *f, const char **subdirs,
 318     int nsubdirs, const char *refname, time_t mtime,
 319     enum got_hash_algorithm algo)
 320 {
 321         const struct got_error *err = NULL;
 322         char *abs_refname;
 323         char *line = NULL;
 324         size_t linesize = 0;
 325         ssize_t linelen;
 326         int i, ref_is_absolute = (strncmp(refname, "refs/", 5) == 0);
 327
 328         *ref = NULL;
 329
 330         if (ref_is_absolute)
 331                 abs_refname = (char *)refname;
 332         do {
 333                 linelen = getline(&line, &linesize, f);
 334                 if (linelen == -1) {
 335                         if (feof(f))
 336                                 break;
 337                         err = got_ferror(f, GOT_ERR_BAD_REF_DATA);
 338                         break;
 339                 }
 340                 if (linelen > 0 && line[linelen - 1] == '\n')
 341                         line[linelen - 1] = '\0';
 342                 for (i = 0; i < nsubdirs; i++) {
 343                         if (!ref_is_absolute &&
 344                             asprintf(&abs_refname, "refs/%s/%s", subdirs[i],
 345                             refname) == -1)
 346                                 return got_error_from_errno("asprintf");
 347                         err = parse_packed_ref_line(ref, abs_refname, line,
 348                             mtime, algo);
 349                         if (!ref_is_absolute)
 350                                 free(abs_refname);
 351                         if (err || *ref != NULL)
 352                                 break;
 353                 }
 354                 if (err)
 355                         break;
 356         } while (*ref == NULL);
 357         free(line);
 358
 359         return err;
 360 }
 361
 362 static const struct got_error *
 363 open_ref(struct got_reference **ref, const char *path_refs, const char *subdir,
 364     const char *name, int lock, enum got_hash_algorithm algo)
 365 {
 366         const struct got_error *err = NULL;
 367         char *path = NULL;
 368         char *absname = NULL;
 369         int ref_is_absolute = (strncmp(name, "refs/", 5) == 0);
 370         int ref_is_well_known = (subdir[0] == '\0' && is_well_known_ref(name));
 371
 372         *ref = NULL;
 373
 374         if (!got_ref_name_is_valid(name))
 375                 return got_error_path(name, GOT_ERR_BAD_REF_NAME);
 376
 377         if (ref_is_absolute || ref_is_well_known) {
 378                 if (asprintf(&path, "%s/%s", path_refs, name) == -1)
 379                         return got_error_from_errno("asprintf");
 380                 absname = (char *)name;
 381         } else {
 382                 if (asprintf(&path, "%s/%s%s%s", path_refs, subdir,
 383                     subdir[0] ? "/" : "", name) == -1)
 384                         return got_error_from_errno("asprintf");
 385
 386                 if (asprintf(&absname, "refs/%s%s%s",
 387                     subdir, subdir[0] ? "/" : "", name) == -1) {
 388                         err = got_error_from_errno("asprintf");
 389                         goto done;
 390                 }
 391         }
 392
 393         err = parse_ref_file(ref, name, absname, path, lock, algo);
 394 done:
 395         if (!ref_is_absolute && !ref_is_well_known)
 396                 free(absname);
 397         free(path);
 398         return err;
 399 }
 400
 401 const struct got_error *
 402 got_ref_open(struct got_reference **ref, struct got_repository *repo,
 403     const char *refname, int lock)
 404 {
 405         const struct got_error *err = NULL;
 406         char *packed_refs_path = NULL, *path_refs = NULL;
 407         const char *subdirs[] = {
 408             GOT_REF_HEADS, GOT_REF_TAGS, GOT_REF_REMOTES
 409         };
 410         size_t i;
 411         int well_known = is_well_known_ref(refname);
 412         struct got_lockfile *lf = NULL;
 413
 414         *ref = NULL;
 415
 416         path_refs = get_refs_dir_path(repo, refname);
 417         if (path_refs == NULL) {
 418                 err = got_error_from_errno2("get_refs_dir_path", refname);
 419                 goto done;
 420         }
 421
 422         if (well_known) {
 423                 err = open_ref(ref, path_refs, "", refname, lock,
 424                     got_repo_get_object_format(repo));
 425         } else {
 426                 FILE *f;
 427
 428                 /* Search on-disk refs before packed refs! */
 429                 for (i = 0; i < nitems(subdirs); i++) {
 430                         err = open_ref(ref, path_refs, subdirs[i], refname,
 431                             lock, got_repo_get_object_format(repo));
 432                         if ((err && err->code != GOT_ERR_NOT_REF) || *ref)
 433                                 goto done;
 434                 }
 435
 436                 packed_refs_path = got_repo_get_path_packed_refs(repo);
 437                 if (packed_refs_path == NULL) {
 438                         err = got_error_from_errno(
 439                             "got_repo_get_path_packed_refs");
 440                         goto done;
 441                 }
 442
 443                 if (lock) {
 444                         err = got_lockfile_lock(&lf, packed_refs_path, -1);
 445                         if (err)
 446                                 goto done;
 447                 }
 448                 f = fopen(packed_refs_path, "rbe");
 449                 if (f != NULL) {
 450                         struct stat sb;
 451                         if (fstat(fileno(f), &sb) == -1) {
 452                                 err = got_error_from_errno2("fstat",
 453                                     packed_refs_path);
 454                                 goto done;
 455                         }
 456                         err = open_packed_ref(ref, f, subdirs, nitems(subdirs),
 457                             refname, sb.st_mtime,
 458                             got_repo_get_object_format(repo));
 459                         if (!err) {
 460                                 if (fclose(f) == EOF) {
 461                                         err = got_error_from_errno("fclose");
 462                                         got_ref_close(*ref);
 463                                         *ref = NULL;
 464                                 } else if (*ref)
 465                                         (*ref)->lf = lf;
 466                         }
 467                 }
 468         }
 469 done:
 470         if (!err && *ref == NULL)
 471                 err = got_error_not_ref(refname);
 472         if (err && lf)
 473                 got_lockfile_unlock(lf, -1);
 474         free(packed_refs_path);
 475         free(path_refs);
 476         return err;
 477 }
 478
 479 void
 480 got_ref_close(struct got_reference *ref)
 481 {
 482         if (ref->flags & GOT_REF_IS_SYMBOLIC) {
 483                 free(ref->ref.symref.name);
 484                 free(ref->ref.symref.ref);
 485         } else
 486                 free(ref->ref.ref.name);
 487         free(ref);
 488 }
 489
 490 struct got_reference *
 491 got_ref_dup(struct got_reference *ref)
 492 {
 493         struct got_reference *ret;
 494
 495         ret = calloc(1, sizeof(*ret));
 496         if (ret == NULL)
 497                 return NULL;
 498
 499         ret->flags = ref->flags;
 500         if (ref->flags & GOT_REF_IS_SYMBOLIC) {
 501                 ret->ref.symref.name = strdup(ref->ref.symref.name);
 502                 if (ret->ref.symref.name == NULL) {
 503                         free(ret);
 504                         return NULL;
 505                 }
 506                 ret->ref.symref.ref = strdup(ref->ref.symref.ref);
 507                 if (ret->ref.symref.ref == NULL) {
 508                         free(ret->ref.symref.name);
 509                         free(ret);
 510                         return NULL;
 511                 }
 512         } else {
 513                 ret->ref.ref.name = strdup(ref->ref.ref.name);
 514                 if (ret->ref.ref.name == NULL) {
 515                         free(ret);
 516                         return NULL;
 517                 }
 518                 memcpy(&ret->ref.ref.id, &ref->ref.ref.id,
 519                     sizeof(ret->ref.ref.id));
 520         }
 521
 522         return ret;
 523 }
 524
 525 const struct got_error *
 526 got_reflist_entry_dup(struct got_reflist_entry **newp,
 527     struct got_reflist_entry *re)
 528 {
 529         const struct got_error *err = NULL;
 530         struct got_reflist_entry *new;
 531
 532         *newp = NULL;
 533
 534         new = malloc(sizeof(*new));
 535         if (new == NULL)
 536                 return got_error_from_errno("malloc");
 537
 538         new->ref = got_ref_dup(re->ref);
 539         if (new->ref == NULL) {
 540                 err = got_error_from_errno("got_ref_dup");
 541                 free(new);
 542                 return err;
 543         }
 544
 545         *newp = new;
 546         return NULL;
 547 }
 548
 549 const struct got_error *
 550 got_ref_resolve_symbolic(struct got_reference **resolved,
 551     struct got_repository *repo, struct got_reference *ref)
 552 {
 553         struct got_reference *nextref;
 554         const struct got_error *err;
 555
 556         err = got_ref_open(&nextref, repo, ref->ref.symref.ref, 0);
 557         if (err)
 558                 return err;
 559
 560         if (nextref->flags & GOT_REF_IS_SYMBOLIC)
 561                 err = got_ref_resolve_symbolic(resolved, repo, nextref);
 562         else
 563                 *resolved = got_ref_dup(nextref);
 564
 565         got_ref_close(nextref);
 566         return err;
 567 }
 568
 569 static const struct got_error *
 570 ref_resolve(struct got_object_id **id, struct got_repository *repo,
 571     struct got_reference *ref, int recursion)
 572 {
 573         const struct got_error *err;
 574
 575         if (recursion <= 0)
 576                 return got_error_msg(GOT_ERR_RECURSION,
 577                     "reference recursion limit reached");
 578
 579         if (ref->flags & GOT_REF_IS_SYMBOLIC) {
 580                 struct got_reference *resolved = NULL;
 581                 err = got_ref_resolve_symbolic(&resolved, repo, ref);
 582                 if (err == NULL)
 583                         err = ref_resolve(id, repo, resolved, --recursion);
 584                 if (resolved)
 585                         got_ref_close(resolved);
 586                 return err;
 587         }
 588
 589         *id = calloc(1, sizeof(**id));
 590         if (*id == NULL)
 591                 return got_error_from_errno("calloc");
 592         memcpy(*id, &ref->ref.ref.id, sizeof(**id));
 593         return NULL;
 594 }
 595
 596 const struct got_error *
 597 got_ref_resolve(struct got_object_id **id, struct got_repository *repo,
 598     struct got_reference *ref)
 599 {
 600         return ref_resolve(id, repo, ref, GOT_REF_RECURSE_MAX);
 601 }
 602
 603 char *
 604 got_ref_to_str(struct got_reference *ref)
 605 {
 606         char *str;
 607
 608         if (ref->flags & GOT_REF_IS_SYMBOLIC)
 609                 return strdup(ref->ref.symref.ref);
 610
 611         if (got_object_id_str(&str, &ref->ref.ref.id) != NULL)
 612                 return NULL;
 613
 614         return str;
 615 }
 616
 617 const char *
 618 got_ref_get_name(struct got_reference *ref)
 619 {
 620         if (ref->flags & GOT_REF_IS_SYMBOLIC)
 621                 return ref->ref.symref.name;
 622
 623         return ref->ref.ref.name;
 624 }
 625
 626 const char *
 627 got_ref_get_symref_target(struct got_reference *ref)
 628 {
 629         if (ref->flags & GOT_REF_IS_SYMBOLIC)
 630                 return ref->ref.symref.ref;
 631
 632         return NULL;
 633 }
 634
 635 time_t
 636 got_ref_get_mtime(struct got_reference *ref)
 637 {
 638         return ref->mtime;
 639 }
 640
 641 const struct got_error *
 642 got_ref_cmp_by_name(void *arg, int *cmp, struct got_reference *re1,
 643     struct got_reference* re2)
 644 {
 645         const char *name1 = got_ref_get_name(re1);
 646         const char *name2 = got_ref_get_name(re2);
 647
 648         *cmp = got_path_cmp(name1, name2, strlen(name1), strlen(name2));
 649         return NULL;
 650 }
 651
 652 const struct got_error *
 653 got_ref_cmp_tags(void *arg, int *cmp, struct got_reference *ref1,
 654     struct got_reference *ref2)
 655 {
 656         const struct got_error *err = NULL;
 657         struct got_repository *repo = arg;
 658         struct got_object_id *id1, *id2 = NULL;
 659         struct got_tag_object *tag1 = NULL, *tag2 = NULL;
 660         struct got_commit_object *commit1 = NULL, *commit2 = NULL;
 661         time_t time1, time2;
 662
 663         *cmp = 0;
 664
 665         err = got_ref_resolve(&id1, repo, ref1);
 666         if (err)
 667                 return err;
 668         err = got_object_open_as_tag(&tag1, repo, id1);
 669         if (err) {
 670                 if (err->code != GOT_ERR_OBJ_TYPE)
 671                         goto done;
 672                 /* "lightweight" tag */
 673                 err = got_object_open_as_commit(&commit1, repo, id1);
 674                 if (err)
 675                         goto done;
 676                 time1 = got_object_commit_get_committer_time(commit1);
 677         } else
 678                 time1 = got_object_tag_get_tagger_time(tag1);
 679
 680         err = got_ref_resolve(&id2, repo, ref2);
 681         if (err)
 682                 goto done;
 683         err = got_object_open_as_tag(&tag2, repo, id2);
 684         if (err) {
 685                 if (err->code != GOT_ERR_OBJ_TYPE)
 686                         goto done;
 687                 /* "lightweight" tag */
 688                 err = got_object_open_as_commit(&commit2, repo, id2);
 689                 if (err)
 690                         goto done;
 691                 time2 = got_object_commit_get_committer_time(commit2);
 692         } else
 693                 time2 = got_object_tag_get_tagger_time(tag2);
 694
 695         /* Put latest tags first. */
 696         if (time1 < time2)
 697                 *cmp = 1;
 698         else if (time1 > time2)
 699                 *cmp = -1;
 700         else
 701                 err = got_ref_cmp_by_name(NULL, cmp, ref2, ref1);
 702 done:
 703         free(id1);
 704         free(id2);
 705         if (tag1)
 706                 got_object_tag_close(tag1);
 707         if (tag2)
 708                 got_object_tag_close(tag2);
 709         if (commit1)
 710                 got_object_commit_close(commit1);
 711         if (commit2)
 712                 got_object_commit_close(commit2);
 713         return err;
 714 }
 715
 716 static const struct got_error *
 717 get_committer_time(struct got_reference *ref, struct got_repository *repo)
 718 {
 719         const struct got_error *err = NULL;
 720         int obj_type;
 721         struct got_commit_object *commit = NULL;
 722         struct got_tag_object *tag = NULL;
 723         struct got_object_id *id = NULL;
 724
 725         err = got_ref_resolve(&id, repo, ref);
 726         if (err)
 727                 return err;
 728
 729         err = got_object_get_type(&obj_type, repo, id);
 730         if (err)
 731                 goto done;
 732
 733         switch (obj_type) {
 734         case GOT_OBJ_TYPE_COMMIT:
 735                 err = got_object_open_as_commit(&commit, repo, id);
 736                 if (err)
 737                         goto done;
 738                 ref->committer_time =
 739                     got_object_commit_get_committer_time(commit);
 740                 break;
 741         case GOT_OBJ_TYPE_TAG:
 742                 err = got_object_open_as_tag(&tag, repo, id);
 743                 if (err)
 744                         goto done;
 745                 ref->committer_time = got_object_tag_get_tagger_time(tag);
 746                 break;
 747         default:
 748                 /* best effort for other object types */
 749                 ref->committer_time = got_ref_get_mtime(ref);
 750                 break;
 751         }
 752 done:
 753         free(id);
 754         if (commit)
 755                 got_object_commit_close(commit);
 756         if (tag)
 757                 got_object_tag_close(tag);
 758         return err;
 759 }
 760
 761 const struct got_error *
 762 got_ref_cmp_by_commit_timestamp_descending(void *arg, int *cmp,
 763     struct got_reference *ref1, struct got_reference *ref2)
 764 {
 765         const struct got_error *err = NULL;
 766         struct got_repository *repo = arg;
 767
 768         *cmp = 0;
 769
 770         if (ref1->committer_time == 0) {
 771                 err = get_committer_time(ref1, repo);
 772                 if (err)
 773                         return err;
 774         }
 775         if (ref2->committer_time == 0) {
 776                 err = get_committer_time(ref2, repo);
 777                 if (err)
 778                         return err;
 779         }
 780
 781         if (ref1->committer_time < ref2->committer_time)
 782                 *cmp = 1;
 783         else if (ref2->committer_time < ref1->committer_time)
 784                 *cmp = -1;
 785         else
 786                 return got_ref_cmp_by_name(arg, cmp, ref1, ref2);
 787
 788         return err;
 789 }
 790
 791 const struct got_error *
 792 got_reflist_insert(struct got_reflist_entry **newp,
 793     struct got_reflist_head *refs, struct got_reference *ref,
 794     got_ref_cmp_cb cmp_cb, void *cmp_arg)
 795 {
 796         const struct got_error *err;
 797         struct got_reflist_entry *new, *re;
 798         int cmp;
 799
 800         *newp = NULL;
 801
 802         if (cmp_cb != got_ref_cmp_by_name && (ref->flags & GOT_REF_IS_PACKED)) {
 803                 /*
 804                  * If we are not sorting elements by name then we must still
 805                  * detect collisions between a packed ref and an on-disk ref
 806                  * using the same name. On-disk refs take precedence and are
 807                  * already present on the list before packed refs get added.
 808                  */
 809                 TAILQ_FOREACH(re, refs, entry) {
 810                         err = got_ref_cmp_by_name(NULL, &cmp, re->ref, ref);
 811                         if (err)
 812                                 return err;
 813                         if (cmp == 0)
 814                                 return NULL;
 815                 }
 816         }
 817
 818         new = malloc(sizeof(*new));
 819         if (new == NULL)
 820                 return got_error_from_errno("malloc");
 821         new->ref = ref;
 822         *newp = new;
 823
 824         /*
 825          * We must de-duplicate entries on insert because packed-refs may
 826          * contain redundant entries. On-disk refs take precedence.
 827          * This code assumes that on-disk revs are read before packed-refs.
 828          * We're iterating the list anyway, so insert elements sorted by name.
 829          *
 830          * Many callers will provide paths in a somewhat sorted order.
 831          * Iterating backwards from the tail of the list should be more
 832          * efficient than traversing through the entire list each time
 833          * an element is inserted.
 834          */
 835         re = TAILQ_LAST(refs, got_reflist_head);
 836         while (re) {
 837                 err = (*cmp_cb)(cmp_arg, &cmp, re->ref, new->ref);
 838                 if (err)
 839                         return err;
 840                 if (cmp == 0) {
 841                         /* duplicate */
 842                         free(new);
 843                         *newp = NULL;
 844                         return NULL;
 845                 } else if (cmp < 0) {
 846                         TAILQ_INSERT_AFTER(refs, re, new, entry);
 847                         return NULL;
 848                 }
 849                 re = TAILQ_PREV(re, got_reflist_head, entry);
 850         }
 851
 852         TAILQ_INSERT_HEAD(refs, new, entry);
 853         return NULL;
 854 }
 855
 856 const struct got_error *
 857 got_reflist_sort(struct got_reflist_head *refs,
 858     got_ref_cmp_cb cmp_cb, void *cmp_arg)
 859 {
 860         const struct got_error *err = NULL;
 861         struct got_reflist_entry *re, *tmp, *new;
 862         struct got_reflist_head sorted;
 863
 864         TAILQ_INIT(&sorted);
 865
 866         TAILQ_FOREACH_SAFE(re, refs, entry, tmp) {
 867                 struct got_reference *ref = re->ref;
 868                 TAILQ_REMOVE(refs, re, entry);
 869                 free(re);
 870                 err = got_reflist_insert(&new, &sorted, ref, cmp_cb, cmp_arg);
 871                 if (err || new == NULL /* duplicate */)
 872                         got_ref_close(ref);
 873                 if (err)
 874                         return err;
 875         }
 876
 877         TAILQ_CONCAT(refs, &sorted, entry);
 878         return NULL;
 879 }
 880
 881 static const struct got_error *
 882 gather_on_disk_refs(struct got_reflist_head *refs, const char *path_refs,
 883     const char *subdir, struct got_repository *repo,
 884     got_ref_cmp_cb cmp_cb, void *cmp_arg)
 885 {
 886         const struct got_error *err = NULL;
 887         DIR *d = NULL;
 888         char *path_subdir;
 889
 890         while (subdir[0] == '/')
 891                 subdir++;
 892
 893         if (asprintf(&path_subdir, "%s/%s", path_refs, subdir) == -1)
 894                 return got_error_from_errno("asprintf");
 895
 896         d = opendir(path_subdir);
 897         if (d == NULL)
 898                 goto done;
 899
 900         for (;;) {
 901                 struct dirent *dent;
 902                 struct got_reference *ref;
 903                 char *child;
 904                 int type;
 905
 906                 dent = readdir(d);
 907                 if (dent == NULL)
 908                         break;
 909
 910                 if (strcmp(dent->d_name, ".") == 0 ||
 911                     strcmp(dent->d_name, "..") == 0)
 912                         continue;
 913
 914                 err = got_path_dirent_type(&type, path_subdir, dent);
 915                 if (err)
 916                         break;
 917
 918                 switch (type) {
 919                 case DT_REG:
 920                         err = open_ref(&ref, path_refs, subdir, dent->d_name,
 921                             0, got_repo_get_object_format(repo));
 922                         if (err)
 923                                 goto done;
 924                         if (ref) {
 925                                 struct got_reflist_entry *new;
 926                                 err = got_reflist_insert(&new, refs, ref,
 927                                     cmp_cb, cmp_arg);
 928                                 if (err || new == NULL /* duplicate */)
 929                                         got_ref_close(ref);
 930                                 if (err)
 931                                         goto done;
 932                         }
 933                         break;
 934                 case DT_DIR:
 935                         if (asprintf(&child, "%s%s%s", subdir,
 936                             subdir[0] == '\0' ? "" : "/", dent->d_name) == -1) {
 937                                 err = got_error_from_errno("asprintf");
 938                                 break;
 939                         }
 940                         err = gather_on_disk_refs(refs, path_refs, child, repo,
 941                             cmp_cb, cmp_arg);
 942                         free(child);
 943                         break;
 944                 default:
 945                         break;
 946                 }
 947         }
 948 done:
 949         if (d)
 950                 closedir(d);
 951         free(path_subdir);
 952         return err;
 953 }
 954
 955 const struct got_error *
 956 got_ref_list(struct got_reflist_head *refs, struct got_repository *repo,
 957     const char *ref_namespace, got_ref_cmp_cb cmp_cb, void *cmp_arg)
 958 {
 959         const struct got_error *err;
 960         char *packed_refs_path = NULL, *path_refs = NULL;
 961         char *abs_namespace = NULL, *buf = NULL;
 962         const char *ondisk_ref_namespace = NULL;
 963         char *line = NULL;
 964         FILE *f = NULL;
 965         struct got_reference *ref;
 966         struct got_reflist_entry *new;
 967
 968         if (ref_namespace == NULL || ref_namespace[0] == '\0') {
 969                 path_refs = get_refs_dir_path(repo, GOT_REF_HEAD);
 970                 if (path_refs == NULL) {
 971                         err = got_error_from_errno("get_refs_dir_path");
 972                         goto done;
 973                 }
 974                 err = open_ref(&ref, path_refs, "", GOT_REF_HEAD, 0,
 975                     got_repo_get_object_format(repo));
 976                 if (err)
 977                         goto done;
 978                 err = got_reflist_insert(&new, refs, ref, cmp_cb, cmp_arg);
 979                 if (err || new == NULL /* duplicate */)
 980                         got_ref_close(ref);
 981                 if (err && err->code != GOT_ERR_NOT_REF)
 982                         goto done;
 983         } else {
 984                 /* Try listing a single reference. */
 985                 const char *refname = ref_namespace;
 986                 path_refs = get_refs_dir_path(repo, refname);
 987                 if (path_refs == NULL) {
 988                         err = got_error_from_errno("get_refs_dir_path");
 989                         goto done;
 990                 }
 991                 err = open_ref(&ref, path_refs, "", refname, 0,
 992                     got_repo_get_object_format(repo));
 993                 if (err) {
 994                         if (err->code != GOT_ERR_NOT_REF)
 995                                 goto done;
 996                         /* Try to look up references in a given namespace. */
 997                 } else {
 998                         err = got_reflist_insert(&new, refs, ref,
 999                             cmp_cb, cmp_arg);
1000                         if (err || new == NULL /* duplicate */)
1001                                 got_ref_close(ref);
1002                         return err;
1003                 }
1004         }
1005
1006         if (ref_namespace) {
1007                 size_t len;
1008                 /* Canonicalize the path to eliminate double-slashes if any. */
1009                 if (asprintf(&abs_namespace, "/%s", ref_namespace) == -1) {
1010                         err = got_error_from_errno("asprintf");
1011                         goto done;
1012                 }
1013                 len = strlen(abs_namespace) + 1;
1014                 buf = malloc(len);
1015                 if (buf == NULL) {
1016                         err = got_error_from_errno("malloc");
1017                         goto done;
1018                 }
1019                 err = got_canonpath(abs_namespace, buf, len);
1020                 if (err)
1021                         goto done;
1022                 ondisk_ref_namespace = buf;
1023                 while (ondisk_ref_namespace[0] == '/')
1024                         ondisk_ref_namespace++;
1025                 if (strncmp(ondisk_ref_namespace, "refs/", 5) == 0)
1026                         ondisk_ref_namespace += 5;
1027                 else if (strcmp(ondisk_ref_namespace, "refs") == 0)
1028                         ondisk_ref_namespace = "";
1029         }
1030
1031         /* Gather on-disk refs before parsing packed-refs. */
1032         free(path_refs);
1033         path_refs = get_refs_dir_path(repo, "");
1034         if (path_refs == NULL) {
1035                 err = got_error_from_errno("get_refs_dir_path");
1036                 goto done;
1037         }
1038         err = gather_on_disk_refs(refs, path_refs,
1039             ondisk_ref_namespace ? ondisk_ref_namespace : "", repo,
1040             cmp_cb, cmp_arg);
1041         if (err)
1042                 goto done;
1043
1044         /*
1045          * The packed-refs file may contain redundant entries, in which
1046          * case on-disk refs take precedence.
1047          */
1048         packed_refs_path = got_repo_get_path_packed_refs(repo);
1049         if (packed_refs_path == NULL) {
1050                 err = got_error_from_errno("got_repo_get_path_packed_refs");
1051                 goto done;
1052         }
1053
1054         f = fopen(packed_refs_path, "re");
1055         if (f) {
1056                 size_t linesize = 0;
1057                 ssize_t linelen;
1058                 struct stat sb;
1059
1060                 if (fstat(fileno(f), &sb) == -1) {
1061                         err = got_error_from_errno2("fstat", packed_refs_path);
1062                         goto done;
1063                 }
1064                 for (;;) {
1065                         linelen = getline(&line, &linesize, f);
1066                         if (linelen == -1) {
1067                                 if (feof(f))
1068                                         break;
1069                                 err = got_ferror(f, GOT_ERR_BAD_REF_DATA);
1070                                 goto done;
1071                         }
1072                         if (linelen > 0 && line[linelen - 1] == '\n')
1073                                 line[linelen - 1] = '\0';
1074                         err = parse_packed_ref_line(&ref, NULL, line,
1075                             sb.st_mtime, got_repo_get_object_format(repo));
1076                         if (err)
1077                                 goto done;
1078                         if (ref) {
1079                                 if (ref_namespace) {
1080                                         const char *name;
1081                                         name = got_ref_get_name(ref);
1082                                         if (!got_path_is_child(name,
1083                                             ref_namespace,
1084                                             strlen(ref_namespace))) {
1085                                                 got_ref_close(ref);
1086                                                 continue;
1087                                         }
1088                                 }
1089                                 err = got_reflist_insert(&new, refs, ref,
1090                                     cmp_cb, cmp_arg);
1091                                 if (err || new == NULL /* duplicate */)
1092                                         got_ref_close(ref);
1093                                 if (err)
1094                                         goto done;
1095                         }
1096                 }
1097         }
1098 done:
1099         free(packed_refs_path);
1100         free(abs_namespace);
1101         free(buf);
1102         free(line);
1103         free(path_refs);
1104         if (f && fclose(f) == EOF && err == NULL)
1105                 err = got_error_from_errno("fclose");
1106         return err;
1107 }
1108
1109 void
1110 got_ref_list_free(struct got_reflist_head *refs)
1111 {
1112         struct got_reflist_entry *re;
1113
1114         while ((re = TAILQ_FIRST(refs))) {
1115                 TAILQ_REMOVE(refs, re, entry);
1116                 got_ref_close(re->ref);
1117                 free(re);
1118         }
1119 }
1120
1121 int
1122 got_ref_is_symbolic(struct got_reference *ref)
1123 {
1124         return (ref->flags & GOT_REF_IS_SYMBOLIC);
1125 }
1126
1127 const struct got_error *
1128 got_ref_change_ref(struct got_reference *ref, struct got_object_id *id)
1129 {
1130         if (ref->flags & GOT_REF_IS_SYMBOLIC)
1131                 return got_error(GOT_ERR_BAD_REF_TYPE);
1132
1133         memcpy(&ref->ref.ref.id, id, sizeof(ref->ref.ref.id));
1134         return NULL;
1135 }
1136
1137 const struct got_error *
1138 got_ref_change_symref(struct got_reference *ref, const char *refname)
1139 {
1140         char *new_name;
1141
1142         if ((ref->flags & GOT_REF_IS_SYMBOLIC) == 0)
1143                 return got_error(GOT_ERR_BAD_REF_TYPE);
1144
1145         new_name = strdup(refname);
1146         if (new_name == NULL)
1147                 return got_error_from_errno("strdup");
1148
1149         free(ref->ref.symref.ref);
1150         ref->ref.symref.ref = new_name;
1151         return NULL;
1152 }
1153
1154 const struct got_error *
1155 got_ref_change_symref_to_ref(struct got_reference *symref,
1156     struct got_object_id *id)
1157 {
1158         if ((symref->flags & GOT_REF_IS_SYMBOLIC) == 0)
1159                 return got_error(GOT_ERR_BAD_REF_TYPE);
1160
1161         symref->ref.ref.name = symref->ref.symref.name;
1162         memcpy(&symref->ref.ref.id, id, sizeof(symref->ref.ref.id));
1163         symref->flags &= ~GOT_REF_IS_SYMBOLIC;
1164         return NULL;
1165 }
1166
1167 const struct got_error *
1168 got_ref_write(struct got_reference *ref, struct got_repository *repo)
1169 {
1170         const struct got_error *err = NULL, *unlock_err = NULL;
1171         const char *name = got_ref_get_name(ref);
1172         char *path_refs = NULL, *path = NULL, *tmppath = NULL;
1173         struct got_lockfile *lf = NULL;
1174         FILE *f = NULL;
1175         size_t n;
1176         struct stat sb;
1177
1178         path_refs = get_refs_dir_path(repo, name);
1179         if (path_refs == NULL) {
1180                 err = got_error_from_errno2("get_refs_dir_path", name);
1181                 goto done;
1182         }
1183
1184         if (asprintf(&path, "%s/%s", path_refs, name) == -1) {
1185                 err = got_error_from_errno("asprintf");
1186                 goto done;
1187         }
1188
1189         err = got_opentemp_named(&tmppath, &f, path, "");
1190         if (err) {
1191                 char *parent;
1192                 if (!(err->code == GOT_ERR_ERRNO && errno == ENOENT))
1193                         goto done;
1194                 err = got_path_dirname(&parent, path);
1195                 if (err)
1196                         goto done;
1197                 err = got_path_mkdir(parent);
1198                 free(parent);
1199                 if (err)
1200                         goto done;
1201                 err = got_opentemp_named(&tmppath, &f, path, "");
1202                 if (err)
1203                         goto done;
1204         }
1205
1206         if (ref->flags & GOT_REF_IS_SYMBOLIC) {
1207                 n = fprintf(f, "ref: %s\n", ref->ref.symref.ref);
1208                 if (n != strlen(ref->ref.symref.ref) + 6) {
1209                         err = got_ferror(f, GOT_ERR_IO);
1210                         goto done;
1211                 }
1212         } else {
1213                 char *hex;
1214                 size_t len;
1215
1216                 err = got_object_id_str(&hex, &ref->ref.ref.id);
1217                 if (err)
1218                         goto done;
1219                 len = strlen(hex);
1220                 n = fprintf(f, "%s\n", hex);
1221                 free(hex);
1222                 if (n != len + 1) {
1223                         err = got_ferror(f, GOT_ERR_IO);
1224                         goto done;
1225                 }
1226         }
1227
1228         if (ref->lf == NULL) {
1229                 err = got_lockfile_lock(&lf, path, -1);
1230                 if (err)
1231                         goto done;
1232         }
1233
1234         /* XXX: check if old content matches our expectations? */
1235
1236         if (stat(path, &sb) != 0) {
1237                 if (errno != ENOENT) {
1238                         err = got_error_from_errno2("stat", path);
1239                         goto done;
1240                 }
1241                 sb.st_mode = GOT_DEFAULT_FILE_MODE;
1242         }
1243
1244         if (fchmod(fileno(f), sb.st_mode) != 0) {
1245                 err = got_error_from_errno2("fchmod", tmppath);
1246                 goto done;
1247         }
1248
1249         if (rename(tmppath, path) != 0) {
1250                 err = got_error_from_errno3("rename", tmppath, path);
1251                 goto done;
1252         }
1253         free(tmppath);
1254         tmppath = NULL;
1255
1256         if (stat(path, &sb) == -1) {
1257                 err = got_error_from_errno2("stat", path);
1258                 goto done;
1259         }
1260         ref->mtime = sb.st_mtime;
1261 done:
1262         if (ref->lf == NULL && lf)
1263                 unlock_err = got_lockfile_unlock(lf, -1);
1264         if (f) {
1265                 if (fclose(f) == EOF && err == NULL)
1266                         err = got_error_from_errno("fclose");
1267         }
1268         free(path_refs);
1269         free(path);
1270         if (tmppath) {
1271                 if (unlink(tmppath) == -1 && err == NULL)
1272                         err = got_error_from_errno2("unlink", tmppath);
1273                 free(tmppath);
1274         }
1275         return err ? err : unlock_err;
1276 }
1277
1278 static const struct got_error *
1279 delete_packed_ref(struct got_reference *delref, struct got_repository *repo)
1280 {
1281         const struct got_error *err = NULL, *unlock_err = NULL;
1282         struct got_lockfile *lf = NULL;
1283         FILE *f = NULL, *tmpf = NULL;
1284         char *line = NULL, *packed_refs_path, *tmppath = NULL;
1285         size_t linesize = 0;
1286         struct got_reflist_head refs;
1287         int found_delref = 0;
1288
1289         /* The packed-refs file does not cotain symbolic references. */
1290         if (delref->flags & GOT_REF_IS_SYMBOLIC)
1291                 return got_error(GOT_ERR_BAD_REF_DATA);
1292
1293         TAILQ_INIT(&refs);
1294
1295         packed_refs_path = got_repo_get_path_packed_refs(repo);
1296         if (packed_refs_path == NULL)
1297                 return got_error_from_errno("got_repo_get_path_packed_refs");
1298
1299         err = got_opentemp_named(&tmppath, &tmpf, packed_refs_path, "");
1300         if (err)
1301                 goto done;
1302
1303         if (delref->lf == NULL) {
1304                 err = got_lockfile_lock(&lf, packed_refs_path, -1);
1305                 if (err)
1306                         goto done;
1307         }
1308
1309         f = fopen(packed_refs_path, "re");
1310         if (f == NULL) {
1311                 err = got_error_from_errno2("fopen", packed_refs_path);
1312                 goto done;
1313         }
1314         for (;;) {
1315                 ssize_t linelen;
1316                 struct got_reference *ref;
1317                 struct got_reflist_entry *new;
1318
1319                 linelen = getline(&line, &linesize, f);
1320                 if (linelen == -1) {
1321                         if (feof(f))
1322                                 break;
1323                         err = got_ferror(f, GOT_ERR_BAD_REF_DATA);
1324                         goto done;
1325                 }
1326                 if (linelen > 0 && line[linelen - 1] == '\n')
1327                         line[linelen - 1] = '\0';
1328                 err = parse_packed_ref_line(&ref, NULL, line, 0,
1329                     got_repo_get_object_format(repo));
1330                 if (err)
1331                         goto done;
1332                 if (ref == NULL)
1333                         continue;
1334
1335                 if (strcmp(ref->ref.ref.name, delref->ref.ref.name) == 0 &&
1336                     got_object_id_cmp(&ref->ref.ref.id,
1337                     &delref->ref.ref.id) == 0) {
1338                         found_delref = 1;
1339                         got_ref_close(ref);
1340                         continue;
1341                 }
1342
1343                 err = got_reflist_insert(&new, &refs, ref,
1344                     got_ref_cmp_by_name, NULL);
1345                 if (err || new == NULL /* duplicate */)
1346                         got_ref_close(ref);
1347                 if (err)
1348                         goto done;
1349         }
1350
1351         if (found_delref) {
1352                 struct got_reflist_entry *re;
1353                 size_t n;
1354                 struct stat sb;
1355
1356                 n = fprintf(tmpf, "%s\n", GOT_PACKED_REFS_HEADER);
1357                 if (n != sizeof(GOT_PACKED_REFS_HEADER)) {
1358                         err = got_ferror(f, GOT_ERR_IO);
1359                         goto done;
1360                 }
1361
1362                 TAILQ_FOREACH(re, &refs, entry) {
1363                         char *hex;
1364                         size_t len;
1365
1366                         err = got_object_id_str(&hex, &re->ref->ref.ref.id);
1367                         if (err)
1368                                 goto done;
1369                         len = strlen(hex);
1370                         n = fprintf(tmpf, "%s ", hex);
1371                         free(hex);
1372                         if (n != len + 1) {
1373                                 err = got_ferror(f, GOT_ERR_IO);
1374                                 goto done;
1375                         }
1376
1377                         n = fprintf(tmpf, "%s\n", re->ref->ref.ref.name);
1378                         if (n != strlen(re->ref->ref.ref.name) + 1) {
1379                                 err = got_ferror(f, GOT_ERR_IO);
1380                                 goto done;
1381                         }
1382                 }
1383
1384                 if (fflush(tmpf) != 0) {
1385                         err = got_error_from_errno("fflush");
1386                         goto done;
1387                 }
1388
1389                 if (fstat(fileno(f), &sb) != 0) {
1390                         if (errno != ENOENT) {
1391                                 err = got_error_from_errno2("fstat",
1392                                     packed_refs_path);
1393                                 goto done;
1394                         }
1395                         sb.st_mode = GOT_DEFAULT_FILE_MODE;
1396                 }
1397
1398                 if (fchmod(fileno(tmpf), sb.st_mode) != 0) {
1399                         err = got_error_from_errno2("fchmod", tmppath);
1400                         goto done;
1401                 }
1402
1403                 if (rename(tmppath, packed_refs_path) != 0) {
1404                         err = got_error_from_errno3("rename", tmppath,
1405                             packed_refs_path);
1406                         goto done;
1407                 }
1408                 free(tmppath);
1409                 tmppath = NULL;
1410         }
1411 done:
1412         if (delref->lf == NULL && lf)
1413                 unlock_err = got_lockfile_unlock(lf, -1);
1414         if (f) {
1415                 if (fclose(f) == EOF && err == NULL)
1416                         err = got_error_from_errno("fclose");
1417         }
1418         if (tmppath && unlink(tmppath) == -1 && err == NULL)
1419                 err = got_error_from_errno2("unlink", tmppath);
1420         if (tmpf && fclose(tmpf) == EOF && err == NULL)
1421                 err = got_error_from_errno("fclose");
1422         free(tmppath);
1423         free(packed_refs_path);
1424         free(line);
1425         got_ref_list_free(&refs);
1426         return err ? err : unlock_err;
1427 }
1428
1429 static const struct got_error *
1430 delete_loose_ref(struct got_reference *ref, struct got_repository *repo)
1431 {
1432         const struct got_error *err = NULL, *unlock_err = NULL;
1433         const char *name = got_ref_get_name(ref);
1434         char *path_refs = NULL, *path = NULL;
1435         struct got_lockfile *lf = NULL;
1436
1437         path_refs = get_refs_dir_path(repo, name);
1438         if (path_refs == NULL) {
1439                 err = got_error_from_errno2("get_refs_dir_path", name);
1440                 goto done;
1441         }
1442
1443         if (asprintf(&path, "%s/%s", path_refs, name) == -1) {
1444                 err = got_error_from_errno("asprintf");
1445                 goto done;
1446         }
1447
1448         if (ref->lf == NULL) {
1449                 err = got_lockfile_lock(&lf, path, -1);
1450                 if (err)
1451                         goto done;
1452         }
1453
1454         /* XXX: check if old content matches our expectations? */
1455
1456         if (unlink(path) == -1)
1457                 err = got_error_from_errno2("unlink", path);
1458 done:
1459         if (ref->lf == NULL && lf)
1460                 unlock_err = got_lockfile_unlock(lf, -1);
1461
1462         free(path_refs);
1463         free(path);
1464         return err ? err : unlock_err;
1465 }
1466
1467 const struct got_error *
1468 got_ref_delete(struct got_reference *ref, struct got_repository *repo)
1469 {
1470         const struct got_error *err = NULL;
1471         struct got_reference *ref2;
1472
1473         if (ref->flags & GOT_REF_IS_PACKED) {
1474                 err = delete_packed_ref(ref, repo);
1475                 if (err)
1476                         return err;
1477
1478                 err = got_ref_open(&ref2, repo, got_ref_get_name(ref), 0);
1479                 if (err) {
1480                         if (err->code == GOT_ERR_NOT_REF)
1481                                 return NULL;
1482                         return err;
1483                 }
1484
1485                 err = delete_loose_ref(ref2, repo);
1486                 got_ref_close(ref2);
1487                 return err;
1488         } else {
1489                 err = delete_loose_ref(ref, repo);
1490                 if (err)
1491                         return err;
1492
1493                 err = got_ref_open(&ref2, repo, got_ref_get_name(ref), 0);
1494                 if (err) {
1495                         if (err->code == GOT_ERR_NOT_REF)
1496                                 return NULL;
1497                         return err;
1498                 }
1499
1500                 err = delete_packed_ref(ref2, repo);
1501                 got_ref_close(ref2);
1502                 return err;
1503         }
1504 }
1505
1506 const struct got_error *
1507 got_ref_unlock(struct got_reference *ref)
1508 {
1509         const struct got_error *err;
1510         err = got_lockfile_unlock(ref->lf, -1);
1511         ref->lf = NULL;
1512         return err;
1513 }
1514
1515 struct got_reflist_object_id_map {
1516         struct got_object_idset *idset;
1517 };
1518
1519 struct got_reflist_object_id_map_entry {
1520         struct got_reflist_head refs;
1521 };
1522
1523 static const struct got_error *
1524 add_object_id_map_entry(struct got_object_idset *idset,
1525     struct got_object_id *id, struct got_reflist_entry *re)
1526 {
1527         const struct got_error *err = NULL;
1528         struct got_reflist_object_id_map_entry *ent;
1529         struct got_reflist_entry *new;
1530
1531         ent = got_object_idset_get(idset, id);
1532         if (ent == NULL) {
1533                 ent = malloc(sizeof(*ent));
1534                 if (ent == NULL)
1535                         return got_error_from_errno("malloc");
1536
1537                 TAILQ_INIT(&ent->refs);
1538                 err = got_object_idset_add(idset, id, ent);
1539                 if (err) {
1540                         free(ent);
1541                         return err;
1542                 }
1543         }
1544
1545         err = got_reflist_entry_dup(&new, re);
1546         if (err)
1547                 return err;
1548
1549         TAILQ_INSERT_TAIL(&ent->refs, new, entry);
1550         return NULL;
1551 }
1552
1553 const struct got_error *
1554 got_reflist_object_id_map_create(struct got_reflist_object_id_map **map,
1555     struct got_reflist_head *refs, struct got_repository *repo)
1556 {
1557         const struct got_error *err = NULL;
1558         struct got_object_idset *idset;
1559         struct got_object_id *id = NULL;
1560         struct got_reflist_entry *re;
1561
1562         idset = got_object_idset_alloc();
1563         if (idset == NULL)
1564                 return got_error_from_errno("got_object_idset_alloc");
1565
1566         *map = malloc(sizeof(**map));
1567         if (*map == NULL) {
1568                 got_object_idset_free(idset);
1569                 return got_error_from_errno("malloc");
1570         }
1571         (*map)->idset = idset;
1572
1573         TAILQ_FOREACH(re, refs, entry) {
1574                 struct got_tag_object *tag = NULL;
1575
1576                 err = got_ref_resolve(&id, repo, re->ref);
1577                 if (err)
1578                         goto done;
1579
1580                 err = add_object_id_map_entry(idset, id, re);
1581                 if (err)
1582                         goto done;
1583
1584                 if (strstr(got_ref_get_name(re->ref), "/tags/") == NULL) {
1585                         free(id);
1586                         id = NULL;
1587                         continue;
1588                 }
1589
1590                 err = got_object_open_as_tag(&tag, repo, id);
1591                 if (err) {
1592                         if (err->code != GOT_ERR_OBJ_TYPE)
1593                                 goto done;
1594                         /* Ref points at something other than a tag. */
1595                         err = NULL;
1596                         tag = NULL;
1597                         free(id);
1598                         id = NULL;
1599                         continue;
1600                 }
1601
1602                 err = add_object_id_map_entry(idset,
1603                     got_object_tag_get_object_id(tag), re);
1604                 got_object_tag_close(tag);
1605                 if (err)
1606                         goto done;
1607
1608                 free(id);
1609                 id = NULL;
1610         }
1611 done:
1612         free(id);
1613         if (err) {
1614                 got_reflist_object_id_map_free(*map);
1615                 *map = NULL;
1616         }
1617         return err;
1618 }
1619
1620 struct got_reflist_head *
1621 got_reflist_object_id_map_lookup(struct got_reflist_object_id_map *map,
1622     struct got_object_id *id)
1623 {
1624         struct got_reflist_object_id_map_entry *ent;
1625         ent = got_object_idset_get(map->idset, id);
1626         if (ent)
1627                 return &ent->refs;
1628         return NULL;
1629 }
1630
1631 static const struct got_error *
1632 free_id_map_entry(struct got_object_id *id, void *data, void *arg)
1633 {
1634         struct got_reflist_object_id_map_entry *ent = data;
1635
1636         got_ref_list_free(&ent->refs);
1637         free(ent);
1638         return NULL;
1639 }
1640
1641 void
1642 got_reflist_object_id_map_free(struct got_reflist_object_id_map *map)
1643 {
1644         got_object_idset_for_each(map->idset, free_id_map_entry, NULL);
1645         got_object_idset_free(map->idset);
1646         free(map);
1647 }