builtin/worktree.c

   1 #include "cache.h"
   2 #include "checkout.h"
   3 #include "config.h"
   4 #include "builtin.h"
   5 #include "dir.h"
   6 #include "parse-options.h"
   7 #include "strvec.h"
   8 #include "branch.h"
   9 #include "refs.h"
  10 #include "run-command.h"
  11 #include "sigchain.h"
  12 #include "submodule.h"
  13 #include "utf8.h"
  14 #include "worktree.h"
  15
  16 static const char * const worktree_usage[] = {
  17         N_("git worktree add [<options>] <path> [<commit-ish>]"),
  18         N_("git worktree list [<options>]"),
  19         N_("git worktree lock [<options>] <path>"),
  20         N_("git worktree move <worktree> <new-path>"),
  21         N_("git worktree prune [<options>]"),
  22         N_("git worktree remove [<options>] <worktree>"),
  23         N_("git worktree unlock <path>"),
  24         NULL
  25 };
  26
  27 struct add_opts {
  28         int force;
  29         int detach;
  30         int quiet;
  31         int checkout;
  32         int keep_locked;
  33 };
  34
  35 static int show_only;
  36 static int verbose;
  37 static int guess_remote;
  38 static timestamp_t expire;
  39
  40 static int git_worktree_config(const char *var, const char *value, void *cb)
  41 {
  42         if (!strcmp(var, "worktree.guessremote")) {
  43                 guess_remote = git_config_bool(var, value);
  44                 return 0;
  45         }
  46
  47         return git_default_config(var, value, cb);
  48 }
  49
  50 static int delete_git_dir(const char *id)
  51 {
  52         struct strbuf sb = STRBUF_INIT;
  53         int ret;
  54
  55         strbuf_addstr(&sb, git_common_path("worktrees/%s", id));
  56         ret = remove_dir_recursively(&sb, 0);
  57         if (ret < 0 && errno == ENOTDIR)
  58                 ret = unlink(sb.buf);
  59         if (ret)
  60                 error_errno(_("failed to delete '%s'"), sb.buf);
  61         strbuf_release(&sb);
  62         return ret;
  63 }
  64
  65 static void delete_worktrees_dir_if_empty(void)
  66 {
  67         rmdir(git_path("worktrees")); /* ignore failed removal */
  68 }
  69
  70 /*
  71  * Return true if worktree entry should be pruned, along with the reason for
  72  * pruning. Otherwise, return false and the worktree's path, or NULL if it
  73  * cannot be determined. Caller is responsible for freeing returned path.
  74  */
  75 static int should_prune_worktree(const char *id, struct strbuf *reason, char **wtpath)
  76 {
  77         struct stat st;
  78         char *path;
  79         int fd;
  80         size_t len;
  81         ssize_t read_result;
  82
  83         *wtpath = NULL;
  84         if (!is_directory(git_path("worktrees/%s", id))) {
  85                 strbuf_addstr(reason, _("not a valid directory"));
  86                 return 1;
  87         }
  88         if (file_exists(git_path("worktrees/%s/locked", id)))
  89                 return 0;
  90         if (stat(git_path("worktrees/%s/gitdir", id), &st)) {
  91                 strbuf_addstr(reason, _("gitdir file does not exist"));
  92                 return 1;
  93         }
  94         fd = open(git_path("worktrees/%s/gitdir", id), O_RDONLY);
  95         if (fd < 0) {
  96                 strbuf_addf(reason, _("unable to read gitdir file (%s)"),
  97                             strerror(errno));
  98                 return 1;
  99         }
 100         len = xsize_t(st.st_size);
 101         path = xmallocz(len);
 102
 103         read_result = read_in_full(fd, path, len);
 104         if (read_result < 0) {
 105                 strbuf_addf(reason, _("unable to read gitdir file (%s)"),
 106                             strerror(errno));
 107                 close(fd);
 108                 free(path);
 109                 return 1;
 110         }
 111         close(fd);
 112
 113         if (read_result != len) {
 114                 strbuf_addf(reason,
 115                             _("short read (expected %"PRIuMAX" bytes, read %"PRIuMAX")"),
 116                             (uintmax_t)len, (uintmax_t)read_result);
 117                 free(path);
 118                 return 1;
 119         }
 120         while (len && (path[len - 1] == '\n' || path[len - 1] == '\r'))
 121                 len--;
 122         if (!len) {
 123                 strbuf_addstr(reason, _("invalid gitdir file"));
 124                 free(path);
 125                 return 1;
 126         }
 127         path[len] = '\0';
 128         if (!file_exists(path)) {
 129                 if (stat(git_path("worktrees/%s/index", id), &st) ||
 130                     st.st_mtime <= expire) {
 131                         strbuf_addstr(reason, _("gitdir file points to non-existent location"));
 132                         free(path);
 133                         return 1;
 134                 } else {
 135                         *wtpath = path;
 136                         return 0;
 137                 }
 138         }
 139         *wtpath = path;
 140         return 0;
 141 }
 142
 143 static void prune_worktree(const char *id, const char *reason)
 144 {
 145         if (show_only || verbose)
 146                 printf_ln(_("Removing %s/%s: %s"), "worktrees", id, reason);
 147         if (!show_only)
 148                 delete_git_dir(id);
 149 }
 150
 151 static int prune_cmp(const void *a, const void *b)
 152 {
 153         const struct string_list_item *x = a;
 154         const struct string_list_item *y = b;
 155         int c;
 156
 157         if ((c = fspathcmp(x->string, y->string)))
 158             return c;
 159         /*
 160          * paths same; prune_dupes() removes all but the first worktree entry
 161          * having the same path, so sort main worktree ('util' is NULL) above
 162          * linked worktrees ('util' not NULL) since main worktree can't be
 163          * removed
 164          */
 165         if (!x->util)
 166                 return -1;
 167         if (!y->util)
 168                 return 1;
 169         /* paths same; sort by .git/worktrees/<id> */
 170         return strcmp(x->util, y->util);
 171 }
 172
 173 static void prune_dups(struct string_list *l)
 174 {
 175         int i;
 176
 177         QSORT(l->items, l->nr, prune_cmp);
 178         for (i = 1; i < l->nr; i++) {
 179                 if (!fspathcmp(l->items[i].string, l->items[i - 1].string))
 180                         prune_worktree(l->items[i].util, "duplicate entry");
 181         }
 182 }
 183
 184 static void prune_worktrees(void)
 185 {
 186         struct strbuf reason = STRBUF_INIT;
 187         struct strbuf main_path = STRBUF_INIT;
 188         struct string_list kept = STRING_LIST_INIT_NODUP;
 189         DIR *dir = opendir(git_path("worktrees"));
 190         struct dirent *d;
 191         if (!dir)
 192                 return;
 193         while ((d = readdir(dir)) != NULL) {
 194                 char *path;
 195                 if (is_dot_or_dotdot(d->d_name))
 196                         continue;
 197                 strbuf_reset(&reason);
 198                 if (should_prune_worktree(d->d_name, &reason, &path))
 199                         prune_worktree(d->d_name, reason.buf);
 200                 else if (path)
 201                         string_list_append(&kept, path)->util = xstrdup(d->d_name);
 202         }
 203         closedir(dir);
 204
 205         strbuf_add_absolute_path(&main_path, get_git_common_dir());
 206         /* massage main worktree absolute path to match 'gitdir' content */
 207         strbuf_strip_suffix(&main_path, "/.");
 208         string_list_append(&kept, strbuf_detach(&main_path, NULL));
 209         prune_dups(&kept);
 210         string_list_clear(&kept, 1);
 211
 212         if (!show_only)
 213                 delete_worktrees_dir_if_empty();
 214         strbuf_release(&reason);
 215 }
 216
 217 static int prune(int ac, const char **av, const char *prefix)
 218 {
 219         struct option options[] = {
 220                 OPT__DRY_RUN(&show_only, N_("do not remove, show only")),
 221                 OPT__VERBOSE(&verbose, N_("report pruned working trees")),
 222                 OPT_EXPIRY_DATE(0, "expire", &expire,
 223                                 N_("expire working trees older than <time>")),
 224                 OPT_END()
 225         };
 226
 227         expire = TIME_MAX;
 228         ac = parse_options(ac, av, prefix, options, worktree_usage, 0);
 229         if (ac)
 230                 usage_with_options(worktree_usage, options);
 231         prune_worktrees();
 232         return 0;
 233 }
 234
 235 static char *junk_work_tree;
 236 static char *junk_git_dir;
 237 static int is_junk;
 238 static pid_t junk_pid;
 239
 240 static void remove_junk(void)
 241 {
 242         struct strbuf sb = STRBUF_INIT;
 243         if (!is_junk || getpid() != junk_pid)
 244                 return;
 245         if (junk_git_dir) {
 246                 strbuf_addstr(&sb, junk_git_dir);
 247                 remove_dir_recursively(&sb, 0);
 248                 strbuf_reset(&sb);
 249         }
 250         if (junk_work_tree) {
 251                 strbuf_addstr(&sb, junk_work_tree);
 252                 remove_dir_recursively(&sb, 0);
 253         }
 254         strbuf_release(&sb);
 255 }
 256
 257 static void remove_junk_on_signal(int signo)
 258 {
 259         remove_junk();
 260         sigchain_pop(signo);
 261         raise(signo);
 262 }
 263
 264 static const char *worktree_basename(const char *path, int *olen)
 265 {
 266         const char *name;
 267         int len;
 268
 269         len = strlen(path);
 270         while (len && is_dir_sep(path[len - 1]))
 271                 len--;
 272
 273         for (name = path + len - 1; name > path; name--)
 274                 if (is_dir_sep(*name)) {
 275                         name++;
 276                         break;
 277                 }
 278
 279         *olen = len;
 280         return name;
 281 }
 282
 283 /* check that path is viable location for worktree */
 284 static void check_candidate_path(const char *path,
 285                                  int force,
 286                                  struct worktree **worktrees,
 287                                  const char *cmd)
 288 {
 289         struct worktree *wt;
 290         int locked;
 291
 292         if (file_exists(path) && !is_empty_dir(path))
 293                 die(_("'%s' already exists"), path);
 294
 295         wt = find_worktree_by_path(worktrees, path);
 296         if (!wt)
 297                 return;
 298
 299         locked = !!worktree_lock_reason(wt);
 300         if ((!locked && force) || (locked && force > 1)) {
 301                 if (delete_git_dir(wt->id))
 302                     die(_("unusable worktree destination '%s'"), path);
 303                 return;
 304         }
 305
 306         if (locked)
 307                 die(_("'%s' is a missing but locked worktree;\nuse '%s -f -f' to override, or 'unlock' and 'prune' or 'remove' to clear"), cmd, path);
 308         else
 309                 die(_("'%s' is a missing but already registered worktree;\nuse '%s -f' to override, or 'prune' or 'remove' to clear"), cmd, path);
 310 }
 311
 312 static int add_worktree(const char *path, const char *refname,
 313                         const struct add_opts *opts)
 314 {
 315         struct strbuf sb_git = STRBUF_INIT, sb_repo = STRBUF_INIT;
 316         struct strbuf sb = STRBUF_INIT, realpath = STRBUF_INIT;
 317         const char *name;
 318         struct child_process cp = CHILD_PROCESS_INIT;
 319         struct strvec child_env = STRVEC_INIT;
 320         unsigned int counter = 0;
 321         int len, ret;
 322         struct strbuf symref = STRBUF_INIT;
 323         struct commit *commit = NULL;
 324         int is_branch = 0;
 325         struct strbuf sb_name = STRBUF_INIT;
 326         struct worktree **worktrees;
 327
 328         worktrees = get_worktrees();
 329         check_candidate_path(path, opts->force, worktrees, "add");
 330         free_worktrees(worktrees);
 331         worktrees = NULL;
 332
 333         /* is 'refname' a branch or commit? */
 334         if (!opts->detach && !strbuf_check_branch_ref(&symref, refname) &&
 335             ref_exists(symref.buf)) {
 336                 is_branch = 1;
 337                 if (!opts->force)
 338                         die_if_checked_out(symref.buf, 0);
 339         }
 340         commit = lookup_commit_reference_by_name(refname);
 341         if (!commit)
 342                 die(_("invalid reference: %s"), refname);
 343
 344         name = worktree_basename(path, &len);
 345         strbuf_add(&sb, name, path + len - name);
 346         sanitize_refname_component(sb.buf, &sb_name);
 347         if (!sb_name.len)
 348                 BUG("How come '%s' becomes empty after sanitization?", sb.buf);
 349         strbuf_reset(&sb);
 350         name = sb_name.buf;
 351         git_path_buf(&sb_repo, "worktrees/%s", name);
 352         len = sb_repo.len;
 353         if (safe_create_leading_directories_const(sb_repo.buf))
 354                 die_errno(_("could not create leading directories of '%s'"),
 355                           sb_repo.buf);
 356
 357         while (mkdir(sb_repo.buf, 0777)) {
 358                 counter++;
 359                 if ((errno != EEXIST) || !counter /* overflow */)
 360                         die_errno(_("could not create directory of '%s'"),
 361                                   sb_repo.buf);
 362                 strbuf_setlen(&sb_repo, len);
 363                 strbuf_addf(&sb_repo, "%d", counter);
 364         }
 365         name = strrchr(sb_repo.buf, '/') + 1;
 366
 367         junk_pid = getpid();
 368         atexit(remove_junk);
 369         sigchain_push_common(remove_junk_on_signal);
 370
 371         junk_git_dir = xstrdup(sb_repo.buf);
 372         is_junk = 1;
 373
 374         /*
 375          * lock the incomplete repo so prune won't delete it, unlock
 376          * after the preparation is over.
 377          */
 378         strbuf_addf(&sb, "%s/locked", sb_repo.buf);
 379         if (!opts->keep_locked)
 380                 write_file(sb.buf, "initializing");
 381         else
 382                 write_file(sb.buf, "added with --lock");
 383
 384         strbuf_addf(&sb_git, "%s/.git", path);
 385         if (safe_create_leading_directories_const(sb_git.buf))
 386                 die_errno(_("could not create leading directories of '%s'"),
 387                           sb_git.buf);
 388         junk_work_tree = xstrdup(path);
 389
 390         strbuf_reset(&sb);
 391         strbuf_addf(&sb, "%s/gitdir", sb_repo.buf);
 392         strbuf_realpath(&realpath, sb_git.buf, 1);
 393         write_file(sb.buf, "%s", realpath.buf);
 394         strbuf_realpath(&realpath, get_git_common_dir(), 1);
 395         write_file(sb_git.buf, "gitdir: %s/worktrees/%s",
 396                    realpath.buf, name);
 397         /*
 398          * This is to keep resolve_ref() happy. We need a valid HEAD
 399          * or is_git_directory() will reject the directory. Any value which
 400          * looks like an object ID will do since it will be immediately
 401          * replaced by the symbolic-ref or update-ref invocation in the new
 402          * worktree.
 403          */
 404         strbuf_reset(&sb);
 405         strbuf_addf(&sb, "%s/HEAD", sb_repo.buf);
 406         write_file(sb.buf, "%s", oid_to_hex(&null_oid));
 407         strbuf_reset(&sb);
 408         strbuf_addf(&sb, "%s/commondir", sb_repo.buf);
 409         write_file(sb.buf, "../..");
 410
 411         strvec_pushf(&child_env, "%s=%s", GIT_DIR_ENVIRONMENT, sb_git.buf);
 412         strvec_pushf(&child_env, "%s=%s", GIT_WORK_TREE_ENVIRONMENT, path);
 413         cp.git_cmd = 1;
 414
 415         if (!is_branch)
 416                 strvec_pushl(&cp.args, "update-ref", "HEAD",
 417                              oid_to_hex(&commit->object.oid), NULL);
 418         else {
 419                 strvec_pushl(&cp.args, "symbolic-ref", "HEAD",
 420                              symref.buf, NULL);
 421                 if (opts->quiet)
 422                         strvec_push(&cp.args, "--quiet");
 423         }
 424
 425         cp.env = child_env.v;
 426         ret = run_command(&cp);
 427         if (ret)
 428                 goto done;
 429
 430         if (opts->checkout) {
 431                 cp.argv = NULL;
 432                 strvec_clear(&cp.args);
 433                 strvec_pushl(&cp.args, "reset", "--hard", "--no-recurse-submodules", NULL);
 434                 if (opts->quiet)
 435                         strvec_push(&cp.args, "--quiet");
 436                 cp.env = child_env.v;
 437                 ret = run_command(&cp);
 438                 if (ret)
 439                         goto done;
 440         }
 441
 442         is_junk = 0;
 443         FREE_AND_NULL(junk_work_tree);
 444         FREE_AND_NULL(junk_git_dir);
 445
 446 done:
 447         if (ret || !opts->keep_locked) {
 448                 strbuf_reset(&sb);
 449                 strbuf_addf(&sb, "%s/locked", sb_repo.buf);
 450                 unlink_or_warn(sb.buf);
 451         }
 452
 453         /*
 454          * Hook failure does not warrant worktree deletion, so run hook after
 455          * is_junk is cleared, but do return appropriate code when hook fails.
 456          */
 457         if (!ret && opts->checkout) {
 458                 const char *hook = find_hook("post-checkout");
 459                 if (hook) {
 460                         const char *env[] = { "GIT_DIR", "GIT_WORK_TREE", NULL };
 461                         cp.git_cmd = 0;
 462                         cp.no_stdin = 1;
 463                         cp.stdout_to_stderr = 1;
 464                         cp.dir = path;
 465                         cp.env = env;
 466                         cp.argv = NULL;
 467                         cp.trace2_hook_name = "post-checkout";
 468                         strvec_pushl(&cp.args, absolute_path(hook),
 469                                      oid_to_hex(&null_oid),
 470                                      oid_to_hex(&commit->object.oid),
 471                                      "1", NULL);
 472                         ret = run_command(&cp);
 473                 }
 474         }
 475
 476         strvec_clear(&child_env);
 477         strbuf_release(&sb);
 478         strbuf_release(&symref);
 479         strbuf_release(&sb_repo);
 480         strbuf_release(&sb_git);
 481         strbuf_release(&sb_name);
 482         strbuf_release(&realpath);
 483         return ret;
 484 }
 485
 486 static void print_preparing_worktree_line(int detach,
 487                                           const char *branch,
 488                                           const char *new_branch,
 489                                           int force_new_branch)
 490 {
 491         if (force_new_branch) {
 492                 struct commit *commit = lookup_commit_reference_by_name(new_branch);
 493                 if (!commit)
 494                         printf_ln(_("Preparing worktree (new branch '%s')"), new_branch);
 495                 else
 496                         printf_ln(_("Preparing worktree (resetting branch '%s'; was at %s)"),
 497                                   new_branch,
 498                                   find_unique_abbrev(&commit->object.oid, DEFAULT_ABBREV));
 499         } else if (new_branch) {
 500                 printf_ln(_("Preparing worktree (new branch '%s')"), new_branch);
 501         } else {
 502                 struct strbuf s = STRBUF_INIT;
 503                 if (!detach && !strbuf_check_branch_ref(&s, branch) &&
 504                     ref_exists(s.buf))
 505                         printf_ln(_("Preparing worktree (checking out '%s')"),
 506                                   branch);
 507                 else {
 508                         struct commit *commit = lookup_commit_reference_by_name(branch);
 509                         if (!commit)
 510                                 die(_("invalid reference: %s"), branch);
 511                         printf_ln(_("Preparing worktree (detached HEAD %s)"),
 512                                   find_unique_abbrev(&commit->object.oid, DEFAULT_ABBREV));
 513                 }
 514                 strbuf_release(&s);
 515         }
 516 }
 517
 518 static const char *dwim_branch(const char *path, const char **new_branch)
 519 {
 520         int n;
 521         const char *s = worktree_basename(path, &n);
 522         const char *branchname = xstrndup(s, n);
 523         struct strbuf ref = STRBUF_INIT;
 524
 525         UNLEAK(branchname);
 526         if (!strbuf_check_branch_ref(&ref, branchname) &&
 527             ref_exists(ref.buf)) {
 528                 strbuf_release(&ref);
 529                 return branchname;
 530         }
 531
 532         *new_branch = branchname;
 533         if (guess_remote) {
 534                 struct object_id oid;
 535                 const char *remote =
 536                         unique_tracking_name(*new_branch, &oid, NULL);
 537                 return remote;
 538         }
 539         return NULL;
 540 }
 541
 542 static int add(int ac, const char **av, const char *prefix)
 543 {
 544         struct add_opts opts;
 545         const char *new_branch_force = NULL;
 546         char *path;
 547         const char *branch;
 548         const char *new_branch = NULL;
 549         const char *opt_track = NULL;
 550         struct option options[] = {
 551                 OPT__FORCE(&opts.force,
 552                            N_("checkout <branch> even if already checked out in other worktree"),
 553                            PARSE_OPT_NOCOMPLETE),
 554                 OPT_STRING('b', NULL, &new_branch, N_("branch"),
 555                            N_("create a new branch")),
 556                 OPT_STRING('B', NULL, &new_branch_force, N_("branch"),
 557                            N_("create or reset a branch")),
 558                 OPT_BOOL(0, "detach", &opts.detach, N_("detach HEAD at named commit")),
 559                 OPT_BOOL(0, "checkout", &opts.checkout, N_("populate the new working tree")),
 560                 OPT_BOOL(0, "lock", &opts.keep_locked, N_("keep the new working tree locked")),
 561                 OPT__QUIET(&opts.quiet, N_("suppress progress reporting")),
 562                 OPT_PASSTHRU(0, "track", &opt_track, NULL,
 563                              N_("set up tracking mode (see git-branch(1))"),
 564                              PARSE_OPT_NOARG | PARSE_OPT_OPTARG),
 565                 OPT_BOOL(0, "guess-remote", &guess_remote,
 566                          N_("try to match the new branch name with a remote-tracking branch")),
 567                 OPT_END()
 568         };
 569
 570         memset(&opts, 0, sizeof(opts));
 571         opts.checkout = 1;
 572         ac = parse_options(ac, av, prefix, options, worktree_usage, 0);
 573         if (!!opts.detach + !!new_branch + !!new_branch_force > 1)
 574                 die(_("-b, -B, and --detach are mutually exclusive"));
 575         if (ac < 1 || ac > 2)
 576                 usage_with_options(worktree_usage, options);
 577
 578         path = prefix_filename(prefix, av[0]);
 579         branch = ac < 2 ? "HEAD" : av[1];
 580
 581         if (!strcmp(branch, "-"))
 582                 branch = "@{-1}";
 583
 584         if (new_branch_force) {
 585                 struct strbuf symref = STRBUF_INIT;
 586
 587                 new_branch = new_branch_force;
 588
 589                 if (!opts.force &&
 590                     !strbuf_check_branch_ref(&symref, new_branch) &&
 591                     ref_exists(symref.buf))
 592                         die_if_checked_out(symref.buf, 0);
 593                 strbuf_release(&symref);
 594         }
 595
 596         if (ac < 2 && !new_branch && !opts.detach) {
 597                 const char *s = dwim_branch(path, &new_branch);
 598                 if (s)
 599                         branch = s;
 600         }
 601
 602         if (ac == 2 && !new_branch && !opts.detach) {
 603                 struct object_id oid;
 604                 struct commit *commit;
 605                 const char *remote;
 606
 607                 commit = lookup_commit_reference_by_name(branch);
 608                 if (!commit) {
 609                         remote = unique_tracking_name(branch, &oid, NULL);
 610                         if (remote) {
 611                                 new_branch = branch;
 612                                 branch = remote;
 613                         }
 614                 }
 615         }
 616         if (!opts.quiet)
 617                 print_preparing_worktree_line(opts.detach, branch, new_branch, !!new_branch_force);
 618
 619         if (new_branch) {
 620                 struct child_process cp = CHILD_PROCESS_INIT;
 621                 cp.git_cmd = 1;
 622                 strvec_push(&cp.args, "branch");
 623                 if (new_branch_force)
 624                         strvec_push(&cp.args, "--force");
 625                 if (opts.quiet)
 626                         strvec_push(&cp.args, "--quiet");
 627                 strvec_push(&cp.args, new_branch);
 628                 strvec_push(&cp.args, branch);
 629                 if (opt_track)
 630                         strvec_push(&cp.args, opt_track);
 631                 if (run_command(&cp))
 632                         return -1;
 633                 branch = new_branch;
 634         } else if (opt_track) {
 635                 die(_("--[no-]track can only be used if a new branch is created"));
 636         }
 637
 638         UNLEAK(path);
 639         UNLEAK(opts);
 640         return add_worktree(path, branch, &opts);
 641 }
 642
 643 static void show_worktree_porcelain(struct worktree *wt)
 644 {
 645         printf("worktree %s\n", wt->path);
 646         if (wt->is_bare)
 647                 printf("bare\n");
 648         else {
 649                 printf("HEAD %s\n", oid_to_hex(&wt->head_oid));
 650                 if (wt->is_detached)
 651                         printf("detached\n");
 652                 else if (wt->head_ref)
 653                         printf("branch %s\n", wt->head_ref);
 654         }
 655         printf("\n");
 656 }
 657
 658 static void show_worktree(struct worktree *wt, int path_maxlen, int abbrev_len)
 659 {
 660         struct strbuf sb = STRBUF_INIT;
 661         int cur_path_len = strlen(wt->path);
 662         int path_adj = cur_path_len - utf8_strwidth(wt->path);
 663
 664         strbuf_addf(&sb, "%-*s ", 1 + path_maxlen + path_adj, wt->path);
 665         if (wt->is_bare)
 666                 strbuf_addstr(&sb, "(bare)");
 667         else {
 668                 strbuf_addf(&sb, "%-*s ", abbrev_len,
 669                                 find_unique_abbrev(&wt->head_oid, DEFAULT_ABBREV));
 670                 if (wt->is_detached)
 671                         strbuf_addstr(&sb, "(detached HEAD)");
 672                 else if (wt->head_ref) {
 673                         char *ref = shorten_unambiguous_ref(wt->head_ref, 0);
 674                         strbuf_addf(&sb, "[%s]", ref);
 675                         free(ref);
 676                 } else
 677                         strbuf_addstr(&sb, "(error)");
 678         }
 679         printf("%s\n", sb.buf);
 680
 681         strbuf_release(&sb);
 682 }
 683
 684 static void measure_widths(struct worktree **wt, int *abbrev, int *maxlen)
 685 {
 686         int i;
 687
 688         for (i = 0; wt[i]; i++) {
 689                 int sha1_len;
 690                 int path_len = strlen(wt[i]->path);
 691
 692                 if (path_len > *maxlen)
 693                         *maxlen = path_len;
 694                 sha1_len = strlen(find_unique_abbrev(&wt[i]->head_oid, *abbrev));
 695                 if (sha1_len > *abbrev)
 696                         *abbrev = sha1_len;
 697         }
 698 }
 699
 700 static int pathcmp(const void *a_, const void *b_)
 701 {
 702         const struct worktree *const *a = a_;
 703         const struct worktree *const *b = b_;
 704         return fspathcmp((*a)->path, (*b)->path);
 705 }
 706
 707 static void pathsort(struct worktree **wt)
 708 {
 709         int n = 0;
 710         struct worktree **p = wt;
 711
 712         while (*p++)
 713                 n++;
 714         QSORT(wt, n, pathcmp);
 715 }
 716
 717 static int list(int ac, const char **av, const char *prefix)
 718 {
 719         int porcelain = 0;
 720
 721         struct option options[] = {
 722                 OPT_BOOL(0, "porcelain", &porcelain, N_("machine-readable output")),
 723                 OPT_END()
 724         };
 725
 726         ac = parse_options(ac, av, prefix, options, worktree_usage, 0);
 727         if (ac)
 728                 usage_with_options(worktree_usage, options);
 729         else {
 730                 struct worktree **worktrees = get_worktrees();
 731                 int path_maxlen = 0, abbrev = DEFAULT_ABBREV, i;
 732
 733                 /* sort worktrees by path but keep main worktree at top */
 734                 pathsort(worktrees + 1);
 735
 736                 if (!porcelain)
 737                         measure_widths(worktrees, &abbrev, &path_maxlen);
 738
 739                 for (i = 0; worktrees[i]; i++) {
 740                         if (porcelain)
 741                                 show_worktree_porcelain(worktrees[i]);
 742                         else
 743                                 show_worktree(worktrees[i], path_maxlen, abbrev);
 744                 }
 745                 free_worktrees(worktrees);
 746         }
 747         return 0;
 748 }
 749
 750 static int lock_worktree(int ac, const char **av, const char *prefix)
 751 {
 752         const char *reason = "", *old_reason;
 753         struct option options[] = {
 754                 OPT_STRING(0, "reason", &reason, N_("string"),
 755                            N_("reason for locking")),
 756                 OPT_END()
 757         };
 758         struct worktree **worktrees, *wt;
 759
 760         ac = parse_options(ac, av, prefix, options, worktree_usage, 0);
 761         if (ac != 1)
 762                 usage_with_options(worktree_usage, options);
 763
 764         worktrees = get_worktrees();
 765         wt = find_worktree(worktrees, prefix, av[0]);
 766         if (!wt)
 767                 die(_("'%s' is not a working tree"), av[0]);
 768         if (is_main_worktree(wt))
 769                 die(_("The main working tree cannot be locked or unlocked"));
 770
 771         old_reason = worktree_lock_reason(wt);
 772         if (old_reason) {
 773                 if (*old_reason)
 774                         die(_("'%s' is already locked, reason: %s"),
 775                             av[0], old_reason);
 776                 die(_("'%s' is already locked"), av[0]);
 777         }
 778
 779         write_file(git_common_path("worktrees/%s/locked", wt->id),
 780                    "%s", reason);
 781         free_worktrees(worktrees);
 782         return 0;
 783 }
 784
 785 static int unlock_worktree(int ac, const char **av, const char *prefix)
 786 {
 787         struct option options[] = {
 788                 OPT_END()
 789         };
 790         struct worktree **worktrees, *wt;
 791         int ret;
 792
 793         ac = parse_options(ac, av, prefix, options, worktree_usage, 0);
 794         if (ac != 1)
 795                 usage_with_options(worktree_usage, options);
 796
 797         worktrees = get_worktrees();
 798         wt = find_worktree(worktrees, prefix, av[0]);
 799         if (!wt)
 800                 die(_("'%s' is not a working tree"), av[0]);
 801         if (is_main_worktree(wt))
 802                 die(_("The main working tree cannot be locked or unlocked"));
 803         if (!worktree_lock_reason(wt))
 804                 die(_("'%s' is not locked"), av[0]);
 805         ret = unlink_or_warn(git_common_path("worktrees/%s/locked", wt->id));
 806         free_worktrees(worktrees);
 807         return ret;
 808 }
 809
 810 static void validate_no_submodules(const struct worktree *wt)
 811 {
 812         struct index_state istate = { NULL };
 813         struct strbuf path = STRBUF_INIT;
 814         int i, found_submodules = 0;
 815
 816         if (is_directory(worktree_git_path(wt, "modules"))) {
 817                 /*
 818                  * There could be false positives, e.g. the "modules"
 819                  * directory exists but is empty. But it's a rare case and
 820                  * this simpler check is probably good enough for now.
 821                  */
 822                 found_submodules = 1;
 823         } else if (read_index_from(&istate, worktree_git_path(wt, "index"),
 824                                    get_worktree_git_dir(wt)) > 0) {
 825                 for (i = 0; i < istate.cache_nr; i++) {
 826                         struct cache_entry *ce = istate.cache[i];
 827                         int err;
 828
 829                         if (!S_ISGITLINK(ce->ce_mode))
 830                                 continue;
 831
 832                         strbuf_reset(&path);
 833                         strbuf_addf(&path, "%s/%s", wt->path, ce->name);
 834                         if (!is_submodule_populated_gently(path.buf, &err))
 835                                 continue;
 836
 837                         found_submodules = 1;
 838                         break;
 839                 }
 840         }
 841         discard_index(&istate);
 842         strbuf_release(&path);
 843
 844         if (found_submodules)
 845                 die(_("working trees containing submodules cannot be moved or removed"));
 846 }
 847
 848 static int move_worktree(int ac, const char **av, const char *prefix)
 849 {
 850         int force = 0;
 851         struct option options[] = {
 852                 OPT__FORCE(&force,
 853                          N_("force move even if worktree is dirty or locked"),
 854                          PARSE_OPT_NOCOMPLETE),
 855                 OPT_END()
 856         };
 857         struct worktree **worktrees, *wt;
 858         struct strbuf dst = STRBUF_INIT;
 859         struct strbuf errmsg = STRBUF_INIT;
 860         const char *reason = NULL;
 861         char *path;
 862
 863         ac = parse_options(ac, av, prefix, options, worktree_usage, 0);
 864         if (ac != 2)
 865                 usage_with_options(worktree_usage, options);
 866
 867         path = prefix_filename(prefix, av[1]);
 868         strbuf_addstr(&dst, path);
 869         free(path);
 870
 871         worktrees = get_worktrees();
 872         wt = find_worktree(worktrees, prefix, av[0]);
 873         if (!wt)
 874                 die(_("'%s' is not a working tree"), av[0]);
 875         if (is_main_worktree(wt))
 876                 die(_("'%s' is a main working tree"), av[0]);
 877         if (is_directory(dst.buf)) {
 878                 const char *sep = find_last_dir_sep(wt->path);
 879
 880                 if (!sep)
 881                         die(_("could not figure out destination name from '%s'"),
 882                             wt->path);
 883                 strbuf_trim_trailing_dir_sep(&dst);
 884                 strbuf_addstr(&dst, sep);
 885         }
 886         check_candidate_path(dst.buf, force, worktrees, "move");
 887
 888         validate_no_submodules(wt);
 889
 890         if (force < 2)
 891                 reason = worktree_lock_reason(wt);
 892         if (reason) {
 893                 if (*reason)
 894                         die(_("cannot move a locked working tree, lock reason: %s\nuse 'move -f -f' to override or unlock first"),
 895                             reason);
 896                 die(_("cannot move a locked working tree;\nuse 'move -f -f' to override or unlock first"));
 897         }
 898         if (validate_worktree(wt, &errmsg, 0))
 899                 die(_("validation failed, cannot move working tree: %s"),
 900                     errmsg.buf);
 901         strbuf_release(&errmsg);
 902
 903         if (rename(wt->path, dst.buf) == -1)
 904                 die_errno(_("failed to move '%s' to '%s'"), wt->path, dst.buf);
 905
 906         update_worktree_location(wt, dst.buf);
 907
 908         strbuf_release(&dst);
 909         free_worktrees(worktrees);
 910         return 0;
 911 }
 912
 913 /*
 914  * Note, "git status --porcelain" is used to determine if it's safe to
 915  * delete a whole worktree. "git status" does not ignore user
 916  * configuration, so if a normal "git status" shows "clean" for the
 917  * user, then it's ok to remove it.
 918  *
 919  * This assumption may be a bad one. We may want to ignore
 920  * (potentially bad) user settings and only delete a worktree when
 921  * it's absolutely safe to do so from _our_ point of view because we
 922  * know better.
 923  */
 924 static void check_clean_worktree(struct worktree *wt,
 925                                  const char *original_path)
 926 {
 927         struct strvec child_env = STRVEC_INIT;
 928         struct child_process cp;
 929         char buf[1];
 930         int ret;
 931
 932         /*
 933          * Until we sort this out, all submodules are "dirty" and
 934          * will abort this function.
 935          */
 936         validate_no_submodules(wt);
 937
 938         strvec_pushf(&child_env, "%s=%s/.git",
 939                      GIT_DIR_ENVIRONMENT, wt->path);
 940         strvec_pushf(&child_env, "%s=%s",
 941                      GIT_WORK_TREE_ENVIRONMENT, wt->path);
 942         memset(&cp, 0, sizeof(cp));
 943         strvec_pushl(&cp.args, "status",
 944                      "--porcelain", "--ignore-submodules=none",
 945                      NULL);
 946         cp.env = child_env.v;
 947         cp.git_cmd = 1;
 948         cp.dir = wt->path;
 949         cp.out = -1;
 950         ret = start_command(&cp);
 951         if (ret)
 952                 die_errno(_("failed to run 'git status' on '%s'"),
 953                           original_path);
 954         ret = xread(cp.out, buf, sizeof(buf));
 955         if (ret)
 956                 die(_("'%s' contains modified or untracked files, use --force to delete it"),
 957                     original_path);
 958         close(cp.out);
 959         ret = finish_command(&cp);
 960         if (ret)
 961                 die_errno(_("failed to run 'git status' on '%s', code %d"),
 962                           original_path, ret);
 963 }
 964
 965 static int delete_git_work_tree(struct worktree *wt)
 966 {
 967         struct strbuf sb = STRBUF_INIT;
 968         int ret = 0;
 969
 970         strbuf_addstr(&sb, wt->path);
 971         if (remove_dir_recursively(&sb, 0)) {
 972                 error_errno(_("failed to delete '%s'"), sb.buf);
 973                 ret = -1;
 974         }
 975         strbuf_release(&sb);
 976         return ret;
 977 }
 978
 979 static int remove_worktree(int ac, const char **av, const char *prefix)
 980 {
 981         int force = 0;
 982         struct option options[] = {
 983                 OPT__FORCE(&force,
 984                          N_("force removal even if worktree is dirty or locked"),
 985                          PARSE_OPT_NOCOMPLETE),
 986                 OPT_END()
 987         };
 988         struct worktree **worktrees, *wt;
 989         struct strbuf errmsg = STRBUF_INIT;
 990         const char *reason = NULL;
 991         int ret = 0;
 992
 993         ac = parse_options(ac, av, prefix, options, worktree_usage, 0);
 994         if (ac != 1)
 995                 usage_with_options(worktree_usage, options);
 996
 997         worktrees = get_worktrees();
 998         wt = find_worktree(worktrees, prefix, av[0]);
 999         if (!wt)
1000                 die(_("'%s' is not a working tree"), av[0]);
1001         if (is_main_worktree(wt))
1002                 die(_("'%s' is a main working tree"), av[0]);
1003         if (force < 2)
1004                 reason = worktree_lock_reason(wt);
1005         if (reason) {
1006                 if (*reason)
1007                         die(_("cannot remove a locked working tree, lock reason: %s\nuse 'remove -f -f' to override or unlock first"),
1008                             reason);
1009                 die(_("cannot remove a locked working tree;\nuse 'remove -f -f' to override or unlock first"));
1010         }
1011         if (validate_worktree(wt, &errmsg, WT_VALIDATE_WORKTREE_MISSING_OK))
1012                 die(_("validation failed, cannot remove working tree: %s"),
1013                     errmsg.buf);
1014         strbuf_release(&errmsg);
1015
1016         if (file_exists(wt->path)) {
1017                 if (!force)
1018                         check_clean_worktree(wt, av[0]);
1019
1020                 ret |= delete_git_work_tree(wt);
1021         }
1022         /*
1023          * continue on even if ret is non-zero, there's no going back
1024          * from here.
1025          */
1026         ret |= delete_git_dir(wt->id);
1027         delete_worktrees_dir_if_empty();
1028
1029         free_worktrees(worktrees);
1030         return ret;
1031 }
1032
1033 int cmd_worktree(int ac, const char **av, const char *prefix)
1034 {
1035         struct option options[] = {
1036                 OPT_END()
1037         };
1038
1039         git_config(git_worktree_config, NULL);
1040
1041         if (ac < 2)
1042                 usage_with_options(worktree_usage, options);
1043         if (!prefix)
1044                 prefix = "";
1045         if (!strcmp(av[1], "add"))
1046                 return add(ac - 1, av + 1, prefix);
1047         if (!strcmp(av[1], "prune"))
1048                 return prune(ac - 1, av + 1, prefix);
1049         if (!strcmp(av[1], "list"))
1050                 return list(ac - 1, av + 1, prefix);
1051         if (!strcmp(av[1], "lock"))
1052                 return lock_worktree(ac - 1, av + 1, prefix);
1053         if (!strcmp(av[1], "unlock"))
1054                 return unlock_worktree(ac - 1, av + 1, prefix);
1055         if (!strcmp(av[1], "move"))
1056                 return move_worktree(ac - 1, av + 1, prefix);
1057         if (!strcmp(av[1], "remove"))
1058                 return remove_worktree(ac - 1, av + 1, prefix);
1059         usage_with_options(worktree_usage, options);
1060 }