worktree.c

   1 #include "cache.h"
   2 #include "repository.h"
   3 #include "refs.h"
   4 #include "strbuf.h"
   5 #include "worktree.h"
   6 #include "dir.h"
   7 #include "wt-status.h"
   8
   9 void free_worktrees(struct worktree **worktrees)
  10 {
  11         int i = 0;
  12
  13         for (i = 0; worktrees[i]; i++) {
  14                 free(worktrees[i]->path);
  15                 free(worktrees[i]->id);
  16                 free(worktrees[i]->head_ref);
  17                 free(worktrees[i]->lock_reason);
  18                 free(worktrees[i]->prune_reason);
  19                 free(worktrees[i]);
  20         }
  21         free (worktrees);
  22 }
  23
  24 /**
  25  * Update head_oid, head_ref and is_detached of the given worktree
  26  */
  27 static void add_head_info(struct worktree *wt)
  28 {
  29         int flags;
  30         const char *target;
  31
  32         target = refs_resolve_ref_unsafe(get_worktree_ref_store(wt),
  33                                          "HEAD",
  34                                          0,
  35                                          &wt->head_oid, &flags);
  36         if (!target)
  37                 return;
  38
  39         if (flags & REF_ISSYMREF)
  40                 wt->head_ref = xstrdup(target);
  41         else
  42                 wt->is_detached = 1;
  43 }
  44
  45 /**
  46  * get the main worktree
  47  */
  48 static struct worktree *get_main_worktree(void)
  49 {
  50         struct worktree *worktree = NULL;
  51         struct strbuf worktree_path = STRBUF_INIT;
  52
  53         strbuf_add_real_path(&worktree_path, get_git_common_dir());
  54         strbuf_strip_suffix(&worktree_path, "/.git");
  55
  56         CALLOC_ARRAY(worktree, 1);
  57         worktree->path = strbuf_detach(&worktree_path, NULL);
  58         /*
  59          * NEEDSWORK: If this function is called from a secondary worktree and
  60          * config.worktree is present, is_bare_repository_cfg will reflect the
  61          * contents of config.worktree, not the contents of the main worktree.
  62          * This means that worktree->is_bare may be set to 0 even if the main
  63          * worktree is configured to be bare.
  64          */
  65         worktree->is_bare = (is_bare_repository_cfg == 1) ||
  66                 is_bare_repository();
  67         add_head_info(worktree);
  68         return worktree;
  69 }
  70
  71 static struct worktree *get_linked_worktree(const char *id)
  72 {
  73         struct worktree *worktree = NULL;
  74         struct strbuf path = STRBUF_INIT;
  75         struct strbuf worktree_path = STRBUF_INIT;
  76
  77         if (!id)
  78                 die("Missing linked worktree name");
  79
  80         strbuf_git_common_path(&path, the_repository, "worktrees/%s/gitdir", id);
  81         if (strbuf_read_file(&worktree_path, path.buf, 0) <= 0)
  82                 /* invalid gitdir file */
  83                 goto done;
  84         strbuf_rtrim(&worktree_path);
  85         strbuf_strip_suffix(&worktree_path, "/.git");
  86
  87         CALLOC_ARRAY(worktree, 1);
  88         worktree->path = strbuf_detach(&worktree_path, NULL);
  89         worktree->id = xstrdup(id);
  90         add_head_info(worktree);
  91
  92 done:
  93         strbuf_release(&path);
  94         strbuf_release(&worktree_path);
  95         return worktree;
  96 }
  97
  98 static void mark_current_worktree(struct worktree **worktrees)
  99 {
 100         char *git_dir = absolute_pathdup(get_git_dir());
 101         int i;
 102
 103         for (i = 0; worktrees[i]; i++) {
 104                 struct worktree *wt = worktrees[i];
 105                 const char *wt_git_dir = get_worktree_git_dir(wt);
 106
 107                 if (!fspathcmp(git_dir, absolute_path(wt_git_dir))) {
 108                         wt->is_current = 1;
 109                         break;
 110                 }
 111         }
 112         free(git_dir);
 113 }
 114
 115 struct worktree **get_worktrees(void)
 116 {
 117         struct worktree **list = NULL;
 118         struct strbuf path = STRBUF_INIT;
 119         DIR *dir;
 120         struct dirent *d;
 121         int counter = 0, alloc = 2;
 122
 123         ALLOC_ARRAY(list, alloc);
 124
 125         list[counter++] = get_main_worktree();
 126
 127         strbuf_addf(&path, "%s/worktrees", get_git_common_dir());
 128         dir = opendir(path.buf);
 129         strbuf_release(&path);
 130         if (dir) {
 131                 while ((d = readdir_skip_dot_and_dotdot(dir)) != NULL) {
 132                         struct worktree *linked = NULL;
 133
 134                         if ((linked = get_linked_worktree(d->d_name))) {
 135                                 ALLOC_GROW(list, counter + 1, alloc);
 136                                 list[counter++] = linked;
 137                         }
 138                 }
 139                 closedir(dir);
 140         }
 141         ALLOC_GROW(list, counter + 1, alloc);
 142         list[counter] = NULL;
 143
 144         mark_current_worktree(list);
 145         return list;
 146 }
 147
 148 const char *get_worktree_git_dir(const struct worktree *wt)
 149 {
 150         if (!wt)
 151                 return get_git_dir();
 152         else if (!wt->id)
 153                 return get_git_common_dir();
 154         else
 155                 return git_common_path("worktrees/%s", wt->id);
 156 }
 157
 158 static struct worktree *find_worktree_by_suffix(struct worktree **list,
 159                                                 const char *suffix)
 160 {
 161         struct worktree *found = NULL;
 162         int nr_found = 0, suffixlen;
 163
 164         suffixlen = strlen(suffix);
 165         if (!suffixlen)
 166                 return NULL;
 167
 168         for (; *list && nr_found < 2; list++) {
 169                 const char      *path    = (*list)->path;
 170                 int              pathlen = strlen(path);
 171                 int              start   = pathlen - suffixlen;
 172
 173                 /* suffix must start at directory boundary */
 174                 if ((!start || (start > 0 && is_dir_sep(path[start - 1]))) &&
 175                     !fspathcmp(suffix, path + start)) {
 176                         found = *list;
 177                         nr_found++;
 178                 }
 179         }
 180         return nr_found == 1 ? found : NULL;
 181 }
 182
 183 struct worktree *find_worktree(struct worktree **list,
 184                                const char *prefix,
 185                                const char *arg)
 186 {
 187         struct worktree *wt;
 188         char *to_free = NULL;
 189
 190         if ((wt = find_worktree_by_suffix(list, arg)))
 191                 return wt;
 192
 193         if (prefix)
 194                 arg = to_free = prefix_filename(prefix, arg);
 195         wt = find_worktree_by_path(list, arg);
 196         free(to_free);
 197         return wt;
 198 }
 199
 200 struct worktree *find_worktree_by_path(struct worktree **list, const char *p)
 201 {
 202         struct strbuf wt_path = STRBUF_INIT;
 203         char *path = real_pathdup(p, 0);
 204
 205         if (!path)
 206                 return NULL;
 207         for (; *list; list++) {
 208                 if (!strbuf_realpath(&wt_path, (*list)->path, 0))
 209                         continue;
 210
 211                 if (!fspathcmp(path, wt_path.buf))
 212                         break;
 213         }
 214         free(path);
 215         strbuf_release(&wt_path);
 216         return *list;
 217 }
 218
 219 int is_main_worktree(const struct worktree *wt)
 220 {
 221         return !wt->id;
 222 }
 223
 224 const char *worktree_lock_reason(struct worktree *wt)
 225 {
 226         if (is_main_worktree(wt))
 227                 return NULL;
 228
 229         if (!wt->lock_reason_valid) {
 230                 struct strbuf path = STRBUF_INIT;
 231
 232                 strbuf_addstr(&path, worktree_git_path(wt, "locked"));
 233                 if (file_exists(path.buf)) {
 234                         struct strbuf lock_reason = STRBUF_INIT;
 235                         if (strbuf_read_file(&lock_reason, path.buf, 0) < 0)
 236                                 die_errno(_("failed to read '%s'"), path.buf);
 237                         strbuf_trim(&lock_reason);
 238                         wt->lock_reason = strbuf_detach(&lock_reason, NULL);
 239                 } else
 240                         wt->lock_reason = NULL;
 241                 wt->lock_reason_valid = 1;
 242                 strbuf_release(&path);
 243         }
 244
 245         return wt->lock_reason;
 246 }
 247
 248 const char *worktree_prune_reason(struct worktree *wt, timestamp_t expire)
 249 {
 250         struct strbuf reason = STRBUF_INIT;
 251         char *path = NULL;
 252
 253         if (is_main_worktree(wt))
 254                 return NULL;
 255         if (wt->prune_reason_valid)
 256                 return wt->prune_reason;
 257
 258         if (should_prune_worktree(wt->id, &reason, &path, expire))
 259                 wt->prune_reason = strbuf_detach(&reason, NULL);
 260         wt->prune_reason_valid = 1;
 261
 262         strbuf_release(&reason);
 263         free(path);
 264         return wt->prune_reason;
 265 }
 266
 267 /* convenient wrapper to deal with NULL strbuf */
 268 static void strbuf_addf_gently(struct strbuf *buf, const char *fmt, ...)
 269 {
 270         va_list params;
 271
 272         if (!buf)
 273                 return;
 274
 275         va_start(params, fmt);
 276         strbuf_vaddf(buf, fmt, params);
 277         va_end(params);
 278 }
 279
 280 int validate_worktree(const struct worktree *wt, struct strbuf *errmsg,
 281                       unsigned flags)
 282 {
 283         struct strbuf wt_path = STRBUF_INIT;
 284         struct strbuf realpath = STRBUF_INIT;
 285         char *path = NULL;
 286         int err, ret = -1;
 287
 288         strbuf_addf(&wt_path, "%s/.git", wt->path);
 289
 290         if (is_main_worktree(wt)) {
 291                 if (is_directory(wt_path.buf)) {
 292                         ret = 0;
 293                         goto done;
 294                 }
 295                 /*
 296                  * Main worktree using .git file to point to the
 297                  * repository would make it impossible to know where
 298                  * the actual worktree is if this function is executed
 299                  * from another worktree. No .git file support for now.
 300                  */
 301                 strbuf_addf_gently(errmsg,
 302                                    _("'%s' at main working tree is not the repository directory"),
 303                                    wt_path.buf);
 304                 goto done;
 305         }
 306
 307         /*
 308          * Make sure "gitdir" file points to a real .git file and that
 309          * file points back here.
 310          */
 311         if (!is_absolute_path(wt->path)) {
 312                 strbuf_addf_gently(errmsg,
 313                                    _("'%s' file does not contain absolute path to the working tree location"),
 314                                    git_common_path("worktrees/%s/gitdir", wt->id));
 315                 goto done;
 316         }
 317
 318         if (flags & WT_VALIDATE_WORKTREE_MISSING_OK &&
 319             !file_exists(wt->path)) {
 320                 ret = 0;
 321                 goto done;
 322         }
 323
 324         if (!file_exists(wt_path.buf)) {
 325                 strbuf_addf_gently(errmsg, _("'%s' does not exist"), wt_path.buf);
 326                 goto done;
 327         }
 328
 329         path = xstrdup_or_null(read_gitfile_gently(wt_path.buf, &err));
 330         if (!path) {
 331                 strbuf_addf_gently(errmsg, _("'%s' is not a .git file, error code %d"),
 332                                    wt_path.buf, err);
 333                 goto done;
 334         }
 335
 336         strbuf_realpath(&realpath, git_common_path("worktrees/%s", wt->id), 1);
 337         ret = fspathcmp(path, realpath.buf);
 338
 339         if (ret)
 340                 strbuf_addf_gently(errmsg, _("'%s' does not point back to '%s'"),
 341                                    wt->path, git_common_path("worktrees/%s", wt->id));
 342 done:
 343         free(path);
 344         strbuf_release(&wt_path);
 345         strbuf_release(&realpath);
 346         return ret;
 347 }
 348
 349 void update_worktree_location(struct worktree *wt, const char *path_)
 350 {
 351         struct strbuf path = STRBUF_INIT;
 352
 353         if (is_main_worktree(wt))
 354                 BUG("can't relocate main worktree");
 355
 356         strbuf_realpath(&path, path_, 1);
 357         if (fspathcmp(wt->path, path.buf)) {
 358                 write_file(git_common_path("worktrees/%s/gitdir", wt->id),
 359                            "%s/.git", path.buf);
 360                 free(wt->path);
 361                 wt->path = strbuf_detach(&path, NULL);
 362         }
 363         strbuf_release(&path);
 364 }
 365
 366 int is_worktree_being_rebased(const struct worktree *wt,
 367                               const char *target)
 368 {
 369         struct wt_status_state state;
 370         int found_rebase;
 371
 372         memset(&state, 0, sizeof(state));
 373         found_rebase = wt_status_check_rebase(wt, &state) &&
 374                        (state.rebase_in_progress ||
 375                         state.rebase_interactive_in_progress) &&
 376                        state.branch &&
 377                        skip_prefix(target, "refs/heads/", &target) &&
 378                        !strcmp(state.branch, target);
 379         wt_status_state_free_buffers(&state);
 380         return found_rebase;
 381 }
 382
 383 int is_worktree_being_bisected(const struct worktree *wt,
 384                                const char *target)
 385 {
 386         struct wt_status_state state;
 387         int found_bisect;
 388
 389         memset(&state, 0, sizeof(state));
 390         found_bisect = wt_status_check_bisect(wt, &state) &&
 391                        state.branch &&
 392                        skip_prefix(target, "refs/heads/", &target) &&
 393                        !strcmp(state.branch, target);
 394         wt_status_state_free_buffers(&state);
 395         return found_bisect;
 396 }
 397
 398 /*
 399  * note: this function should be able to detect shared symref even if
 400  * HEAD is temporarily detached (e.g. in the middle of rebase or
 401  * bisect). New commands that do similar things should update this
 402  * function as well.
 403  */
 404 const struct worktree *find_shared_symref(const char *symref,
 405                                           const char *target)
 406 {
 407         const struct worktree *existing = NULL;
 408         static struct worktree **worktrees;
 409         int i = 0;
 410
 411         if (worktrees)
 412                 free_worktrees(worktrees);
 413         worktrees = get_worktrees();
 414
 415         for (i = 0; worktrees[i]; i++) {
 416                 struct worktree *wt = worktrees[i];
 417                 const char *symref_target;
 418                 struct ref_store *refs;
 419                 int flags;
 420
 421                 if (wt->is_bare)
 422                         continue;
 423
 424                 if (wt->is_detached && !strcmp(symref, "HEAD")) {
 425                         if (is_worktree_being_rebased(wt, target)) {
 426                                 existing = wt;
 427                                 break;
 428                         }
 429                         if (is_worktree_being_bisected(wt, target)) {
 430                                 existing = wt;
 431                                 break;
 432                         }
 433                 }
 434
 435                 refs = get_worktree_ref_store(wt);
 436                 symref_target = refs_resolve_ref_unsafe(refs, symref, 0,
 437                                                         NULL, &flags);
 438                 if ((flags & REF_ISSYMREF) &&
 439                     symref_target && !strcmp(symref_target, target)) {
 440                         existing = wt;
 441                         break;
 442                 }
 443         }
 444
 445         return existing;
 446 }
 447
 448 int submodule_uses_worktrees(const char *path)
 449 {
 450         char *submodule_gitdir;
 451         struct strbuf sb = STRBUF_INIT, err = STRBUF_INIT;
 452         DIR *dir;
 453         struct dirent *d;
 454         int ret = 0;
 455         struct repository_format format = REPOSITORY_FORMAT_INIT;
 456
 457         submodule_gitdir = git_pathdup_submodule(path, "%s", "");
 458         if (!submodule_gitdir)
 459                 return 0;
 460
 461         /* The env would be set for the superproject. */
 462         get_common_dir_noenv(&sb, submodule_gitdir);
 463         free(submodule_gitdir);
 464
 465         strbuf_addstr(&sb, "/config");
 466         read_repository_format(&format, sb.buf);
 467         if (verify_repository_format(&format, &err)) {
 468                 strbuf_release(&err);
 469                 strbuf_release(&sb);
 470                 clear_repository_format(&format);
 471                 return 1;
 472         }
 473         clear_repository_format(&format);
 474         strbuf_release(&err);
 475
 476         /* Replace config by worktrees. */
 477         strbuf_setlen(&sb, sb.len - strlen("config"));
 478         strbuf_addstr(&sb, "worktrees");
 479
 480         /* See if there is any file inside the worktrees directory. */
 481         dir = opendir(sb.buf);
 482         strbuf_release(&sb);
 483
 484         if (!dir)
 485                 return 0;
 486
 487         d = readdir_skip_dot_and_dotdot(dir);
 488         if (d != NULL)
 489                 ret = 1;
 490         closedir(dir);
 491         return ret;
 492 }
 493
 494 int parse_worktree_ref(const char *worktree_ref, const char **name,
 495                        int *name_length, const char **ref)
 496 {
 497         if (skip_prefix(worktree_ref, "main-worktree/", &worktree_ref)) {
 498                 if (!*worktree_ref)
 499                         return -1;
 500                 if (name)
 501                         *name = NULL;
 502                 if (name_length)
 503                         *name_length = 0;
 504                 if (ref)
 505                         *ref = worktree_ref;
 506                 return 0;
 507         }
 508         if (skip_prefix(worktree_ref, "worktrees/", &worktree_ref)) {
 509                 const char *slash = strchr(worktree_ref, '/');
 510
 511                 if (!slash || slash == worktree_ref || !slash[1])
 512                         return -1;
 513                 if (name)
 514                         *name = worktree_ref;
 515                 if (name_length)
 516                         *name_length = slash - worktree_ref;
 517                 if (ref)
 518                         *ref = slash + 1;
 519                 return 0;
 520         }
 521         return -1;
 522 }
 523
 524 void strbuf_worktree_ref(const struct worktree *wt,
 525                          struct strbuf *sb,
 526                          const char *refname)
 527 {
 528         switch (ref_type(refname)) {
 529         case REF_TYPE_PSEUDOREF:
 530         case REF_TYPE_PER_WORKTREE:
 531                 if (wt && !wt->is_current) {
 532                         if (is_main_worktree(wt))
 533                                 strbuf_addstr(sb, "main-worktree/");
 534                         else
 535                                 strbuf_addf(sb, "worktrees/%s/", wt->id);
 536                 }
 537                 break;
 538
 539         case REF_TYPE_MAIN_PSEUDOREF:
 540         case REF_TYPE_OTHER_PSEUDOREF:
 541                 break;
 542
 543         case REF_TYPE_NORMAL:
 544                 /*
 545                  * For shared refs, don't prefix worktrees/ or
 546                  * main-worktree/. It's not necessary and
 547                  * files-backend.c can't handle it anyway.
 548                  */
 549                 break;
 550         }
 551         strbuf_addstr(sb, refname);
 552 }
 553
 554 int other_head_refs(each_ref_fn fn, void *cb_data)
 555 {
 556         struct worktree **worktrees, **p;
 557         struct strbuf refname = STRBUF_INIT;
 558         int ret = 0;
 559
 560         worktrees = get_worktrees();
 561         for (p = worktrees; *p; p++) {
 562                 struct worktree *wt = *p;
 563                 struct object_id oid;
 564                 int flag;
 565
 566                 if (wt->is_current)
 567                         continue;
 568
 569                 strbuf_reset(&refname);
 570                 strbuf_worktree_ref(wt, &refname, "HEAD");
 571                 if (!refs_read_ref_full(get_main_ref_store(the_repository),
 572                                         refname.buf,
 573                                         RESOLVE_REF_READING,
 574                                         &oid, &flag))
 575                         ret = fn(refname.buf, &oid, flag, cb_data);
 576                 if (ret)
 577                         break;
 578         }
 579         free_worktrees(worktrees);
 580         strbuf_release(&refname);
 581         return ret;
 582 }
 583
 584 /*
 585  * Repair worktree's /path/to/worktree/.git file if missing, corrupt, or not
 586  * pointing at <repo>/worktrees/<id>.
 587  */
 588 static void repair_gitfile(struct worktree *wt,
 589                            worktree_repair_fn fn, void *cb_data)
 590 {
 591         struct strbuf dotgit = STRBUF_INIT;
 592         struct strbuf repo = STRBUF_INIT;
 593         char *backlink;
 594         const char *repair = NULL;
 595         int err;
 596
 597         /* missing worktree can't be repaired */
 598         if (!file_exists(wt->path))
 599                 return;
 600
 601         if (!is_directory(wt->path)) {
 602                 fn(1, wt->path, _("not a directory"), cb_data);
 603                 return;
 604         }
 605
 606         strbuf_realpath(&repo, git_common_path("worktrees/%s", wt->id), 1);
 607         strbuf_addf(&dotgit, "%s/.git", wt->path);
 608         backlink = xstrdup_or_null(read_gitfile_gently(dotgit.buf, &err));
 609
 610         if (err == READ_GITFILE_ERR_NOT_A_FILE)
 611                 fn(1, wt->path, _(".git is not a file"), cb_data);
 612         else if (err)
 613                 repair = _(".git file broken");
 614         else if (fspathcmp(backlink, repo.buf))
 615                 repair = _(".git file incorrect");
 616
 617         if (repair) {
 618                 fn(0, wt->path, repair, cb_data);
 619                 write_file(dotgit.buf, "gitdir: %s", repo.buf);
 620         }
 621
 622         free(backlink);
 623         strbuf_release(&repo);
 624         strbuf_release(&dotgit);
 625 }
 626
 627 static void repair_noop(int iserr, const char *path, const char *msg,
 628                         void *cb_data)
 629 {
 630         /* nothing */
 631 }
 632
 633 void repair_worktrees(worktree_repair_fn fn, void *cb_data)
 634 {
 635         struct worktree **worktrees = get_worktrees();
 636         struct worktree **wt = worktrees + 1; /* +1 skips main worktree */
 637
 638         if (!fn)
 639                 fn = repair_noop;
 640         for (; *wt; wt++)
 641                 repair_gitfile(*wt, fn, cb_data);
 642         free_worktrees(worktrees);
 643 }
 644
 645 static int is_main_worktree_path(const char *path)
 646 {
 647         struct strbuf target = STRBUF_INIT;
 648         struct strbuf maindir = STRBUF_INIT;
 649         int cmp;
 650
 651         strbuf_add_real_path(&target, path);
 652         strbuf_strip_suffix(&target, "/.git");
 653         strbuf_add_real_path(&maindir, get_git_common_dir());
 654         strbuf_strip_suffix(&maindir, "/.git");
 655         cmp = fspathcmp(maindir.buf, target.buf);
 656
 657         strbuf_release(&maindir);
 658         strbuf_release(&target);
 659         return !cmp;
 660 }
 661
 662 /*
 663  * If both the main worktree and linked worktree have been moved, then the
 664  * gitfile /path/to/worktree/.git won't point into the repository, thus we
 665  * won't know which <repo>/worktrees/<id>/gitdir to repair. However, we may
 666  * be able to infer the gitdir by manually reading /path/to/worktree/.git,
 667  * extracting the <id>, and checking if <repo>/worktrees/<id> exists.
 668  */
 669 static char *infer_backlink(const char *gitfile)
 670 {
 671         struct strbuf actual = STRBUF_INIT;
 672         struct strbuf inferred = STRBUF_INIT;
 673         const char *id;
 674
 675         if (strbuf_read_file(&actual, gitfile, 0) < 0)
 676                 goto error;
 677         if (!starts_with(actual.buf, "gitdir:"))
 678                 goto error;
 679         if (!(id = find_last_dir_sep(actual.buf)))
 680                 goto error;
 681         strbuf_trim(&actual);
 682         id++; /* advance past '/' to point at <id> */
 683         if (!*id)
 684                 goto error;
 685         strbuf_git_common_path(&inferred, the_repository, "worktrees/%s", id);
 686         if (!is_directory(inferred.buf))
 687                 goto error;
 688
 689         strbuf_release(&actual);
 690         return strbuf_detach(&inferred, NULL);
 691
 692 error:
 693         strbuf_release(&actual);
 694         strbuf_release(&inferred);
 695         return NULL;
 696 }
 697
 698 /*
 699  * Repair <repo>/worktrees/<id>/gitdir if missing, corrupt, or not pointing at
 700  * the worktree's path.
 701  */
 702 void repair_worktree_at_path(const char *path,
 703                              worktree_repair_fn fn, void *cb_data)
 704 {
 705         struct strbuf dotgit = STRBUF_INIT;
 706         struct strbuf realdotgit = STRBUF_INIT;
 707         struct strbuf gitdir = STRBUF_INIT;
 708         struct strbuf olddotgit = STRBUF_INIT;
 709         char *backlink = NULL;
 710         const char *repair = NULL;
 711         int err;
 712
 713         if (!fn)
 714                 fn = repair_noop;
 715
 716         if (is_main_worktree_path(path))
 717                 goto done;
 718
 719         strbuf_addf(&dotgit, "%s/.git", path);
 720         if (!strbuf_realpath(&realdotgit, dotgit.buf, 0)) {
 721                 fn(1, path, _("not a valid path"), cb_data);
 722                 goto done;
 723         }
 724
 725         backlink = xstrdup_or_null(read_gitfile_gently(realdotgit.buf, &err));
 726         if (err == READ_GITFILE_ERR_NOT_A_FILE) {
 727                 fn(1, realdotgit.buf, _("unable to locate repository; .git is not a file"), cb_data);
 728                 goto done;
 729         } else if (err == READ_GITFILE_ERR_NOT_A_REPO) {
 730                 if (!(backlink = infer_backlink(realdotgit.buf))) {
 731                         fn(1, realdotgit.buf, _("unable to locate repository; .git file does not reference a repository"), cb_data);
 732                         goto done;
 733                 }
 734         } else if (err) {
 735                 fn(1, realdotgit.buf, _("unable to locate repository; .git file broken"), cb_data);
 736                 goto done;
 737         }
 738
 739         strbuf_addf(&gitdir, "%s/gitdir", backlink);
 740         if (strbuf_read_file(&olddotgit, gitdir.buf, 0) < 0)
 741                 repair = _("gitdir unreadable");
 742         else {
 743                 strbuf_rtrim(&olddotgit);
 744                 if (fspathcmp(olddotgit.buf, realdotgit.buf))
 745                         repair = _("gitdir incorrect");
 746         }
 747
 748         if (repair) {
 749                 fn(0, gitdir.buf, repair, cb_data);
 750                 write_file(gitdir.buf, "%s", realdotgit.buf);
 751         }
 752 done:
 753         free(backlink);
 754         strbuf_release(&olddotgit);
 755         strbuf_release(&gitdir);
 756         strbuf_release(&realdotgit);
 757         strbuf_release(&dotgit);
 758 }
 759
 760 int should_prune_worktree(const char *id, struct strbuf *reason, char **wtpath, timestamp_t expire)
 761 {
 762         struct stat st;
 763         char *path;
 764         int fd;
 765         size_t len;
 766         ssize_t read_result;
 767
 768         *wtpath = NULL;
 769         if (!is_directory(git_path("worktrees/%s", id))) {
 770                 strbuf_addstr(reason, _("not a valid directory"));
 771                 return 1;
 772         }
 773         if (file_exists(git_path("worktrees/%s/locked", id)))
 774                 return 0;
 775         if (stat(git_path("worktrees/%s/gitdir", id), &st)) {
 776                 strbuf_addstr(reason, _("gitdir file does not exist"));
 777                 return 1;
 778         }
 779         fd = open(git_path("worktrees/%s/gitdir", id), O_RDONLY);
 780         if (fd < 0) {
 781                 strbuf_addf(reason, _("unable to read gitdir file (%s)"),
 782                             strerror(errno));
 783                 return 1;
 784         }
 785         len = xsize_t(st.st_size);
 786         path = xmallocz(len);
 787
 788         read_result = read_in_full(fd, path, len);
 789         if (read_result < 0) {
 790                 strbuf_addf(reason, _("unable to read gitdir file (%s)"),
 791                             strerror(errno));
 792                 close(fd);
 793                 free(path);
 794                 return 1;
 795         }
 796         close(fd);
 797
 798         if (read_result != len) {
 799                 strbuf_addf(reason,
 800                             _("short read (expected %"PRIuMAX" bytes, read %"PRIuMAX")"),
 801                             (uintmax_t)len, (uintmax_t)read_result);
 802                 free(path);
 803                 return 1;
 804         }
 805         while (len && (path[len - 1] == '\n' || path[len - 1] == '\r'))
 806                 len--;
 807         if (!len) {
 808                 strbuf_addstr(reason, _("invalid gitdir file"));
 809                 free(path);
 810                 return 1;
 811         }
 812         path[len] = '\0';
 813         if (!file_exists(path)) {
 814                 if (stat(git_path("worktrees/%s/index", id), &st) ||
 815                     st.st_mtime <= expire) {
 816                         strbuf_addstr(reason, _("gitdir file points to non-existent location"));
 817                         free(path);
 818                         return 1;
 819                 } else {
 820                         *wtpath = path;
 821                         return 0;
 822                 }
 823         }
 824         *wtpath = path;
 825         return 0;
 826 }