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