builtin/reset.c

   1 /*
   2  * "git reset" builtin command
   3  *
   4  * Copyright (c) 2007 Carlos Rica
   5  *
   6  * Based on git-reset.sh, which is
   7  *
   8  * Copyright (c) 2005, 2006 Linus Torvalds and Junio C Hamano
   9  */
  10 #define USE_THE_INDEX_COMPATIBILITY_MACROS
  11 #include "builtin.h"
  12 #include "config.h"
  13 #include "lockfile.h"
  14 #include "tag.h"
  15 #include "object.h"
  16 #include "pretty.h"
  17 #include "run-command.h"
  18 #include "refs.h"
  19 #include "diff.h"
  20 #include "diffcore.h"
  21 #include "tree.h"
  22 #include "branch.h"
  23 #include "parse-options.h"
  24 #include "unpack-trees.h"
  25 #include "cache-tree.h"
  26 #include "submodule.h"
  27 #include "submodule-config.h"
  28 #include "dir.h"
  29
  30 #define REFRESH_INDEX_DELAY_WARNING_IN_MS (2 * 1000)
  31
  32 static const char * const git_reset_usage[] = {
  33         N_("git reset [--mixed | --soft | --hard | --merge | --keep] [-q] [<commit>]"),
  34         N_("git reset [-q] [<tree-ish>] [--] <pathspec>..."),
  35         N_("git reset [-q] [--pathspec-from-file [--pathspec-file-nul]] [<tree-ish>]"),
  36         N_("git reset --patch [<tree-ish>] [--] [<pathspec>...]"),
  37         NULL
  38 };
  39
  40 enum reset_type { MIXED, SOFT, HARD, MERGE, KEEP, NONE };
  41 static const char *reset_type_names[] = {
  42         N_("mixed"), N_("soft"), N_("hard"), N_("merge"), N_("keep"), NULL
  43 };
  44
  45 static inline int is_merge(void)
  46 {
  47         return !access(git_path_merge_head(the_repository), F_OK);
  48 }
  49
  50 static int reset_index(const char *ref, const struct object_id *oid, int reset_type, int quiet)
  51 {
  52         int i, nr = 0;
  53         struct tree_desc desc[2];
  54         struct tree *tree;
  55         struct unpack_trees_options opts;
  56         int ret = -1;
  57
  58         memset(&opts, 0, sizeof(opts));
  59         opts.head_idx = 1;
  60         opts.src_index = &the_index;
  61         opts.dst_index = &the_index;
  62         opts.fn = oneway_merge;
  63         opts.merge = 1;
  64         init_checkout_metadata(&opts.meta, ref, oid, NULL);
  65         if (!quiet)
  66                 opts.verbose_update = 1;
  67         switch (reset_type) {
  68         case KEEP:
  69         case MERGE:
  70                 opts.update = 1;
  71                 opts.preserve_ignored = 0; /* FIXME: !overwrite_ignore */
  72                 break;
  73         case HARD:
  74                 opts.update = 1;
  75                 opts.reset = UNPACK_RESET_OVERWRITE_UNTRACKED;
  76                 break;
  77         case MIXED:
  78                 opts.reset = UNPACK_RESET_PROTECT_UNTRACKED;
  79                 /* but opts.update=0, so working tree not updated */
  80                 break;
  81         default:
  82                 BUG("invalid reset_type passed to reset_index");
  83         }
  84
  85         read_cache_unmerged();
  86
  87         if (reset_type == KEEP) {
  88                 struct object_id head_oid;
  89                 if (get_oid("HEAD", &head_oid))
  90                         return error(_("You do not have a valid HEAD."));
  91                 if (!fill_tree_descriptor(the_repository, desc + nr, &head_oid))
  92                         return error(_("Failed to find tree of HEAD."));
  93                 nr++;
  94                 opts.fn = twoway_merge;
  95         }
  96
  97         if (!fill_tree_descriptor(the_repository, desc + nr, oid)) {
  98                 error(_("Failed to find tree of %s."), oid_to_hex(oid));
  99                 goto out;
 100         }
 101         nr++;
 102
 103         if (unpack_trees(nr, desc, &opts))
 104                 goto out;
 105
 106         if (reset_type == MIXED || reset_type == HARD) {
 107                 tree = parse_tree_indirect(oid);
 108                 prime_cache_tree(the_repository, the_repository->index, tree);
 109         }
 110
 111         ret = 0;
 112
 113 out:
 114         for (i = 0; i < nr; i++)
 115                 free((void *)desc[i].buffer);
 116         return ret;
 117 }
 118
 119 static void print_new_head_line(struct commit *commit)
 120 {
 121         struct strbuf buf = STRBUF_INIT;
 122
 123         printf(_("HEAD is now at %s"),
 124                 find_unique_abbrev(&commit->object.oid, DEFAULT_ABBREV));
 125
 126         pp_commit_easy(CMIT_FMT_ONELINE, commit, &buf);
 127         if (buf.len > 0)
 128                 printf(" %s", buf.buf);
 129         putchar('\n');
 130         strbuf_release(&buf);
 131 }
 132
 133 static void update_index_from_diff(struct diff_queue_struct *q,
 134                 struct diff_options *opt, void *data)
 135 {
 136         int i;
 137         int intent_to_add = *(int *)data;
 138
 139         for (i = 0; i < q->nr; i++) {
 140                 int pos;
 141                 struct diff_filespec *one = q->queue[i]->one;
 142                 int is_in_reset_tree = one->mode && !is_null_oid(&one->oid);
 143                 struct cache_entry *ce;
 144
 145                 if (!is_in_reset_tree && !intent_to_add) {
 146                         remove_file_from_cache(one->path);
 147                         continue;
 148                 }
 149
 150                 ce = make_cache_entry(&the_index, one->mode, &one->oid, one->path,
 151                                       0, 0);
 152
 153                 /*
 154                  * If the file 1) corresponds to an existing index entry with
 155                  * skip-worktree set, or 2) does not exist in the index but is
 156                  * outside the sparse checkout definition, add a skip-worktree bit
 157                  * to the new index entry. Note that a sparse index will be expanded
 158                  * if this entry is outside the sparse cone - this is necessary
 159                  * to properly construct the reset sparse directory.
 160                  */
 161                 pos = cache_name_pos(one->path, strlen(one->path));
 162                 if ((pos >= 0 && ce_skip_worktree(active_cache[pos])) ||
 163                     (pos < 0 && !path_in_sparse_checkout(one->path, &the_index)))
 164                         ce->ce_flags |= CE_SKIP_WORKTREE;
 165
 166                 if (!ce)
 167                         die(_("make_cache_entry failed for path '%s'"),
 168                             one->path);
 169                 if (!is_in_reset_tree) {
 170                         ce->ce_flags |= CE_INTENT_TO_ADD;
 171                         set_object_name_for_intent_to_add_entry(ce);
 172                 }
 173                 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
 174         }
 175 }
 176
 177 static int pathspec_needs_expanded_index(const struct pathspec *pathspec)
 178 {
 179         unsigned int i, pos;
 180         int res = 0;
 181         char *skip_worktree_seen = NULL;
 182
 183         /*
 184          * When using a magic pathspec, assume for the sake of simplicity that
 185          * the index needs to be expanded to match all matchable files.
 186          */
 187         if (pathspec->magic)
 188                 return 1;
 189
 190         for (i = 0; i < pathspec->nr; i++) {
 191                 struct pathspec_item item = pathspec->items[i];
 192
 193                 /*
 194                  * If the pathspec item has a wildcard, the index should be expanded
 195                  * if the pathspec has the possibility of matching a subset of entries inside
 196                  * of a sparse directory (but not the entire directory).
 197                  *
 198                  * If the pathspec item is a literal path, the index only needs to be expanded
 199                  * if a) the pathspec isn't in the sparse checkout cone (to make sure we don't
 200                  * expand for in-cone files) and b) it doesn't match any sparse directories
 201                  * (since we can reset whole sparse directories without expanding them).
 202                  */
 203                 if (item.nowildcard_len < item.len) {
 204                         /*
 205                          * Special case: if the pattern is a path inside the cone
 206                          * followed by only wildcards, the pattern cannot match
 207                          * partial sparse directories, so we don't expand the index.
 208                          */
 209                         if (path_in_cone_mode_sparse_checkout(item.original, &the_index) &&
 210                             strspn(item.original + item.nowildcard_len, "*") == item.len - item.nowildcard_len)
 211                                 continue;
 212
 213                         for (pos = 0; pos < active_nr; pos++) {
 214                                 struct cache_entry *ce = active_cache[pos];
 215
 216                                 if (!S_ISSPARSEDIR(ce->ce_mode))
 217                                         continue;
 218
 219                                 /*
 220                                  * If the pre-wildcard length is longer than the sparse
 221                                  * directory name and the sparse directory is the first
 222                                  * component of the pathspec, need to expand the index.
 223                                  */
 224                                 if (item.nowildcard_len > ce_namelen(ce) &&
 225                                     !strncmp(item.original, ce->name, ce_namelen(ce))) {
 226                                         res = 1;
 227                                         break;
 228                                 }
 229
 230                                 /*
 231                                  * If the pre-wildcard length is shorter than the sparse
 232                                  * directory and the pathspec does not match the whole
 233                                  * directory, need to expand the index.
 234                                  */
 235                                 if (!strncmp(item.original, ce->name, item.nowildcard_len) &&
 236                                     wildmatch(item.original, ce->name, 0)) {
 237                                         res = 1;
 238                                         break;
 239                                 }
 240                         }
 241                 } else if (!path_in_cone_mode_sparse_checkout(item.original, &the_index) &&
 242                            !matches_skip_worktree(pathspec, i, &skip_worktree_seen))
 243                         res = 1;
 244
 245                 if (res > 0)
 246                         break;
 247         }
 248
 249         free(skip_worktree_seen);
 250         return res;
 251 }
 252
 253 static int read_from_tree(const struct pathspec *pathspec,
 254                           struct object_id *tree_oid,
 255                           int intent_to_add)
 256 {
 257         struct diff_options opt;
 258
 259         memset(&opt, 0, sizeof(opt));
 260         copy_pathspec(&opt.pathspec, pathspec);
 261         opt.output_format = DIFF_FORMAT_CALLBACK;
 262         opt.format_callback = update_index_from_diff;
 263         opt.format_callback_data = &intent_to_add;
 264         opt.flags.override_submodule_config = 1;
 265         opt.flags.recursive = 1;
 266         opt.repo = the_repository;
 267         opt.change = diff_change;
 268         opt.add_remove = diff_addremove;
 269
 270         if (pathspec->nr && the_index.sparse_index && pathspec_needs_expanded_index(pathspec))
 271                 ensure_full_index(&the_index);
 272
 273         if (do_diff_cache(tree_oid, &opt))
 274                 return 1;
 275         diffcore_std(&opt);
 276         diff_flush(&opt);
 277         clear_pathspec(&opt.pathspec);
 278
 279         return 0;
 280 }
 281
 282 static void set_reflog_message(struct strbuf *sb, const char *action,
 283                                const char *rev)
 284 {
 285         const char *rla = getenv("GIT_REFLOG_ACTION");
 286
 287         strbuf_reset(sb);
 288         if (rla)
 289                 strbuf_addf(sb, "%s: %s", rla, action);
 290         else if (rev)
 291                 strbuf_addf(sb, "reset: moving to %s", rev);
 292         else
 293                 strbuf_addf(sb, "reset: %s", action);
 294 }
 295
 296 static void die_if_unmerged_cache(int reset_type)
 297 {
 298         if (is_merge() || unmerged_cache())
 299                 die(_("Cannot do a %s reset in the middle of a merge."),
 300                     _(reset_type_names[reset_type]));
 301
 302 }
 303
 304 static void parse_args(struct pathspec *pathspec,
 305                        const char **argv, const char *prefix,
 306                        int patch_mode,
 307                        const char **rev_ret)
 308 {
 309         const char *rev = "HEAD";
 310         struct object_id unused;
 311         /*
 312          * Possible arguments are:
 313          *
 314          * git reset [-opts] [<rev>]
 315          * git reset [-opts] <tree> [<paths>...]
 316          * git reset [-opts] <tree> -- [<paths>...]
 317          * git reset [-opts] -- [<paths>...]
 318          * git reset [-opts] <paths>...
 319          *
 320          * At this point, argv points immediately after [-opts].
 321          */
 322
 323         if (argv[0]) {
 324                 if (!strcmp(argv[0], "--")) {
 325                         argv++; /* reset to HEAD, possibly with paths */
 326                 } else if (argv[1] && !strcmp(argv[1], "--")) {
 327                         rev = argv[0];
 328                         argv += 2;
 329                 }
 330                 /*
 331                  * Otherwise, argv[0] could be either <rev> or <paths> and
 332                  * has to be unambiguous. If there is a single argument, it
 333                  * can not be a tree
 334                  */
 335                 else if ((!argv[1] && !get_oid_committish(argv[0], &unused)) ||
 336                          (argv[1] && !get_oid_treeish(argv[0], &unused))) {
 337                         /*
 338                          * Ok, argv[0] looks like a commit/tree; it should not
 339                          * be a filename.
 340                          */
 341                         verify_non_filename(prefix, argv[0]);
 342                         rev = *argv++;
 343                 } else {
 344                         /* Otherwise we treat this as a filename */
 345                         verify_filename(prefix, argv[0], 1);
 346                 }
 347         }
 348         *rev_ret = rev;
 349
 350         parse_pathspec(pathspec, 0,
 351                        PATHSPEC_PREFER_FULL |
 352                        (patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0),
 353                        prefix, argv);
 354 }
 355
 356 static int reset_refs(const char *rev, const struct object_id *oid)
 357 {
 358         int update_ref_status;
 359         struct strbuf msg = STRBUF_INIT;
 360         struct object_id *orig = NULL, oid_orig,
 361                 *old_orig = NULL, oid_old_orig;
 362
 363         if (!get_oid("ORIG_HEAD", &oid_old_orig))
 364                 old_orig = &oid_old_orig;
 365         if (!get_oid("HEAD", &oid_orig)) {
 366                 orig = &oid_orig;
 367                 set_reflog_message(&msg, "updating ORIG_HEAD", NULL);
 368                 update_ref(msg.buf, "ORIG_HEAD", orig, old_orig, 0,
 369                            UPDATE_REFS_MSG_ON_ERR);
 370         } else if (old_orig)
 371                 delete_ref(NULL, "ORIG_HEAD", old_orig, 0);
 372         set_reflog_message(&msg, "updating HEAD", rev);
 373         update_ref_status = update_ref(msg.buf, "HEAD", oid, orig, 0,
 374                                        UPDATE_REFS_MSG_ON_ERR);
 375         strbuf_release(&msg);
 376         return update_ref_status;
 377 }
 378
 379 static int git_reset_config(const char *var, const char *value, void *cb)
 380 {
 381         if (!strcmp(var, "submodule.recurse"))
 382                 return git_default_submodule_config(var, value, cb);
 383
 384         return git_default_config(var, value, cb);
 385 }
 386
 387 int cmd_reset(int argc, const char **argv, const char *prefix)
 388 {
 389         int reset_type = NONE, update_ref_status = 0, quiet = 0;
 390         int patch_mode = 0, pathspec_file_nul = 0, unborn;
 391         const char *rev, *pathspec_from_file = NULL;
 392         struct object_id oid;
 393         struct pathspec pathspec;
 394         int intent_to_add = 0;
 395         const struct option options[] = {
 396                 OPT__QUIET(&quiet, N_("be quiet, only report errors")),
 397                 OPT_SET_INT(0, "mixed", &reset_type,
 398                                                 N_("reset HEAD and index"), MIXED),
 399                 OPT_SET_INT(0, "soft", &reset_type, N_("reset only HEAD"), SOFT),
 400                 OPT_SET_INT(0, "hard", &reset_type,
 401                                 N_("reset HEAD, index and working tree"), HARD),
 402                 OPT_SET_INT(0, "merge", &reset_type,
 403                                 N_("reset HEAD, index and working tree"), MERGE),
 404                 OPT_SET_INT(0, "keep", &reset_type,
 405                                 N_("reset HEAD but keep local changes"), KEEP),
 406                 OPT_CALLBACK_F(0, "recurse-submodules", NULL,
 407                             "reset", "control recursive updating of submodules",
 408                             PARSE_OPT_OPTARG, option_parse_recurse_submodules_worktree_updater),
 409                 OPT_BOOL('p', "patch", &patch_mode, N_("select hunks interactively")),
 410                 OPT_BOOL('N', "intent-to-add", &intent_to_add,
 411                                 N_("record only the fact that removed paths will be added later")),
 412                 OPT_PATHSPEC_FROM_FILE(&pathspec_from_file),
 413                 OPT_PATHSPEC_FILE_NUL(&pathspec_file_nul),
 414                 OPT_END()
 415         };
 416
 417         git_config(git_reset_config, NULL);
 418         git_config_get_bool("reset.quiet", &quiet);
 419
 420         argc = parse_options(argc, argv, prefix, options, git_reset_usage,
 421                                                 PARSE_OPT_KEEP_DASHDASH);
 422         parse_args(&pathspec, argv, prefix, patch_mode, &rev);
 423
 424         if (pathspec_from_file) {
 425                 if (patch_mode)
 426                         die(_("options '%s' and '%s' cannot be used together"), "--pathspec-from-file", "--patch");
 427
 428                 if (pathspec.nr)
 429                         die(_("'%s' and pathspec arguments cannot be used together"), "--pathspec-from-file");
 430
 431                 parse_pathspec_file(&pathspec, 0,
 432                                     PATHSPEC_PREFER_FULL,
 433                                     prefix, pathspec_from_file, pathspec_file_nul);
 434         } else if (pathspec_file_nul) {
 435                 die(_("the option '%s' requires '%s'"), "--pathspec-file-nul", "--pathspec-from-file");
 436         }
 437
 438         unborn = !strcmp(rev, "HEAD") && get_oid("HEAD", &oid);
 439         if (unborn) {
 440                 /* reset on unborn branch: treat as reset to empty tree */
 441                 oidcpy(&oid, the_hash_algo->empty_tree);
 442         } else if (!pathspec.nr && !patch_mode) {
 443                 struct commit *commit;
 444                 if (get_oid_committish(rev, &oid))
 445                         die(_("Failed to resolve '%s' as a valid revision."), rev);
 446                 commit = lookup_commit_reference(the_repository, &oid);
 447                 if (!commit)
 448                         die(_("Could not parse object '%s'."), rev);
 449                 oidcpy(&oid, &commit->object.oid);
 450         } else {
 451                 struct tree *tree;
 452                 if (get_oid_treeish(rev, &oid))
 453                         die(_("Failed to resolve '%s' as a valid tree."), rev);
 454                 tree = parse_tree_indirect(&oid);
 455                 if (!tree)
 456                         die(_("Could not parse object '%s'."), rev);
 457                 oidcpy(&oid, &tree->object.oid);
 458         }
 459
 460         if (patch_mode) {
 461                 if (reset_type != NONE)
 462                         die(_("options '%s' and '%s' cannot be used together"), "--patch", "--{hard,mixed,soft}");
 463                 trace2_cmd_mode("patch-interactive");
 464                 return run_add_interactive(rev, "--patch=reset", &pathspec);
 465         }
 466
 467         /* git reset tree [--] paths... can be used to
 468          * load chosen paths from the tree into the index without
 469          * affecting the working tree nor HEAD. */
 470         if (pathspec.nr) {
 471                 if (reset_type == MIXED)
 472                         warning(_("--mixed with paths is deprecated; use 'git reset -- <paths>' instead."));
 473                 else if (reset_type != NONE)
 474                         die(_("Cannot do %s reset with paths."),
 475                                         _(reset_type_names[reset_type]));
 476         }
 477         if (reset_type == NONE)
 478                 reset_type = MIXED; /* by default */
 479
 480         if (pathspec.nr)
 481                 trace2_cmd_mode("path");
 482         else
 483                 trace2_cmd_mode(reset_type_names[reset_type]);
 484
 485         if (reset_type != SOFT && (reset_type != MIXED || get_git_work_tree()))
 486                 setup_work_tree();
 487
 488         if (reset_type == MIXED && is_bare_repository())
 489                 die(_("%s reset is not allowed in a bare repository"),
 490                     _(reset_type_names[reset_type]));
 491
 492         if (intent_to_add && reset_type != MIXED)
 493                 die(_("the option '%s' requires '%s'"), "-N", "--mixed");
 494
 495         prepare_repo_settings(the_repository);
 496         the_repository->settings.command_requires_full_index = 0;
 497
 498         if (read_cache() < 0)
 499                 die(_("index file corrupt"));
 500
 501         /* Soft reset does not touch the index file nor the working tree
 502          * at all, but requires them in a good order.  Other resets reset
 503          * the index file to the tree object we are switching to. */
 504         if (reset_type == SOFT || reset_type == KEEP)
 505                 die_if_unmerged_cache(reset_type);
 506
 507         if (reset_type != SOFT) {
 508                 struct lock_file lock = LOCK_INIT;
 509                 hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
 510                 if (reset_type == MIXED) {
 511                         int flags = quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN;
 512                         if (read_from_tree(&pathspec, &oid, intent_to_add))
 513                                 return 1;
 514                         the_index.updated_skipworktree = 1;
 515                         if (!quiet && get_git_work_tree()) {
 516                                 uint64_t t_begin, t_delta_in_ms;
 517
 518                                 t_begin = getnanotime();
 519                                 refresh_index(&the_index, flags, NULL, NULL,
 520                                               _("Unstaged changes after reset:"));
 521                                 t_delta_in_ms = (getnanotime() - t_begin) / 1000000;
 522                                 if (advice_enabled(ADVICE_RESET_QUIET_WARNING) && t_delta_in_ms > REFRESH_INDEX_DELAY_WARNING_IN_MS) {
 523                                         printf(_("\nIt took %.2f seconds to enumerate unstaged changes after reset.  You can\n"
 524                                                 "use '--quiet' to avoid this.  Set the config setting reset.quiet to true\n"
 525                                                 "to make this the default.\n"), t_delta_in_ms / 1000.0);
 526                                 }
 527                         }
 528                 } else {
 529                         struct object_id dummy;
 530                         char *ref = NULL;
 531                         int err;
 532
 533                         dwim_ref(rev, strlen(rev), &dummy, &ref, 0);
 534                         if (ref && !starts_with(ref, "refs/"))
 535                                 FREE_AND_NULL(ref);
 536
 537                         err = reset_index(ref, &oid, reset_type, quiet);
 538                         if (reset_type == KEEP && !err)
 539                                 err = reset_index(ref, &oid, MIXED, quiet);
 540                         if (err)
 541                                 die(_("Could not reset index file to revision '%s'."), rev);
 542                         free(ref);
 543                 }
 544
 545                 if (write_locked_index(&the_index, &lock, COMMIT_LOCK))
 546                         die(_("Could not write new index file."));
 547         }
 548
 549         if (!pathspec.nr && !unborn) {
 550                 /* Any resets without paths update HEAD to the head being
 551                  * switched to, saving the previous head in ORIG_HEAD before. */
 552                 update_ref_status = reset_refs(rev, &oid);
 553
 554                 if (reset_type == HARD && !update_ref_status && !quiet)
 555                         print_new_head_line(lookup_commit_reference(the_repository, &oid));
 556         }
 557         if (!pathspec.nr)
 558                 remove_branch_state(the_repository, 0);
 559
 560         return update_ref_status;
 561 }