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
  11 #include "builtin.h"
  12 #include "advice.h"
  13 #include "config.h"
  14 #include "environment.h"
  15 #include "gettext.h"
  16 #include "hash.h"
  17 #include "hex.h"
  18 #include "lockfile.h"
  19 #include "object.h"
  20 #include "pretty.h"
  21 #include "refs.h"
  22 #include "diff.h"
  23 #include "diffcore.h"
  24 #include "tree.h"
  25 #include "branch.h"
  26 #include "object-name.h"
  27 #include "parse-options.h"
  28 #include "path.h"
  29 #include "unpack-trees.h"
  30 #include "cache-tree.h"
  31 #include "setup.h"
  32 #include "sparse-index.h"
  33 #include "submodule.h"
  34 #include "trace.h"
  35 #include "trace2.h"
  36 #include "dir.h"
  37 #include "add-interactive.h"
  38
  39 #define REFRESH_INDEX_DELAY_WARNING_IN_MS (2 * 1000)
  40
  41 static const char * const git_reset_usage[] = {
  42         N_("git reset [--mixed | --soft | --hard | --merge | --keep] [-q] [<commit>]"),
  43         N_("git reset [-q] [<tree-ish>] [--] <pathspec>..."),
  44         N_("git reset [-q] [--pathspec-from-file [--pathspec-file-nul]] [<tree-ish>]"),
  45         N_("git reset --patch [<tree-ish>] [--] [<pathspec>...]"),
  46         NULL
  47 };
  48
  49 enum reset_type { MIXED, SOFT, HARD, MERGE, KEEP, NONE };
  50 static const char *reset_type_names[] = {
  51         N_("mixed"), N_("soft"), N_("hard"), N_("merge"), N_("keep"), NULL
  52 };
  53
  54 static inline int is_merge(void)
  55 {
  56         return !access(git_path_merge_head(the_repository), F_OK);
  57 }
  58
  59 static int reset_index(const char *ref, const struct object_id *oid, int reset_type, int quiet)
  60 {
  61         int i, nr = 0;
  62         struct tree_desc desc[2];
  63         struct tree *tree;
  64         struct unpack_trees_options opts;
  65         int ret = -1;
  66
  67         memset(&opts, 0, sizeof(opts));
  68         opts.head_idx = 1;
  69         opts.src_index = the_repository->index;
  70         opts.dst_index = the_repository->index;
  71         opts.fn = oneway_merge;
  72         opts.merge = 1;
  73         init_checkout_metadata(&opts.meta, ref, oid, NULL);
  74         if (!quiet)
  75                 opts.verbose_update = 1;
  76         switch (reset_type) {
  77         case KEEP:
  78         case MERGE:
  79                 opts.update = 1;
  80                 opts.preserve_ignored = 0; /* FIXME: !overwrite_ignore */
  81                 break;
  82         case HARD:
  83                 opts.update = 1;
  84                 opts.reset = UNPACK_RESET_OVERWRITE_UNTRACKED;
  85                 opts.skip_cache_tree_update = 1;
  86                 break;
  87         case MIXED:
  88                 opts.reset = UNPACK_RESET_PROTECT_UNTRACKED;
  89                 opts.skip_cache_tree_update = 1;
  90                 /* but opts.update=0, so working tree not updated */
  91                 break;
  92         default:
  93                 BUG("invalid reset_type passed to reset_index");
  94         }
  95
  96         repo_read_index_unmerged(the_repository);
  97
  98         if (reset_type == KEEP) {
  99                 struct object_id head_oid;
 100                 if (repo_get_oid(the_repository, "HEAD", &head_oid))
 101                         return error(_("You do not have a valid HEAD."));
 102                 if (!fill_tree_descriptor(the_repository, desc + nr, &head_oid))
 103                         return error(_("Failed to find tree of HEAD."));
 104                 nr++;
 105                 opts.fn = twoway_merge;
 106         }
 107
 108         if (!fill_tree_descriptor(the_repository, desc + nr, oid)) {
 109                 error(_("Failed to find tree of %s."), oid_to_hex(oid));
 110                 goto out;
 111         }
 112         nr++;
 113
 114         if (unpack_trees(nr, desc, &opts))
 115                 goto out;
 116
 117         if (reset_type == MIXED || reset_type == HARD) {
 118                 tree = parse_tree_indirect(oid);
 119                 if (!tree) {
 120                         error(_("unable to read tree (%s)"), oid_to_hex(oid));
 121                         goto out;
 122                 }
 123                 prime_cache_tree(the_repository, the_repository->index, tree);
 124         }
 125
 126         ret = 0;
 127
 128 out:
 129         for (i = 0; i < nr; i++)
 130                 free((void *)desc[i].buffer);
 131         return ret;
 132 }
 133
 134 static void print_new_head_line(struct commit *commit)
 135 {
 136         struct strbuf buf = STRBUF_INIT;
 137
 138         printf(_("HEAD is now at %s"),
 139                 repo_find_unique_abbrev(the_repository, &commit->object.oid, DEFAULT_ABBREV));
 140
 141         pp_commit_easy(CMIT_FMT_ONELINE, commit, &buf);
 142         if (buf.len > 0)
 143                 printf(" %s", buf.buf);
 144         putchar('\n');
 145         strbuf_release(&buf);
 146 }
 147
 148 static void update_index_from_diff(struct diff_queue_struct *q,
 149                                    struct diff_options *opt UNUSED,
 150                                    void *data)
 151 {
 152         int i;
 153         int intent_to_add = *(int *)data;
 154
 155         for (i = 0; i < q->nr; i++) {
 156                 int pos;
 157                 struct diff_filespec *one = q->queue[i]->one;
 158                 int is_in_reset_tree = one->mode && !is_null_oid(&one->oid);
 159                 struct cache_entry *ce;
 160
 161                 if (!is_in_reset_tree && !intent_to_add) {
 162                         remove_file_from_index(the_repository->index, one->path);
 163                         continue;
 164                 }
 165
 166                 ce = make_cache_entry(the_repository->index, one->mode, &one->oid, one->path,
 167                                       0, 0);
 168
 169                 /*
 170                  * If the file 1) corresponds to an existing index entry with
 171                  * skip-worktree set, or 2) does not exist in the index but is
 172                  * outside the sparse checkout definition, add a skip-worktree bit
 173                  * to the new index entry. Note that a sparse index will be expanded
 174                  * if this entry is outside the sparse cone - this is necessary
 175                  * to properly construct the reset sparse directory.
 176                  */
 177                 pos = index_name_pos(the_repository->index, one->path, strlen(one->path));
 178                 if ((pos >= 0 && ce_skip_worktree(the_repository->index->cache[pos])) ||
 179                     (pos < 0 && !path_in_sparse_checkout(one->path, the_repository->index)))
 180                         ce->ce_flags |= CE_SKIP_WORKTREE;
 181
 182                 if (!ce)
 183                         die(_("make_cache_entry failed for path '%s'"),
 184                             one->path);
 185                 if (!is_in_reset_tree) {
 186                         ce->ce_flags |= CE_INTENT_TO_ADD;
 187                         set_object_name_for_intent_to_add_entry(ce);
 188                 }
 189                 add_index_entry(the_repository->index, ce,
 190                                 ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
 191         }
 192 }
 193
 194 static int read_from_tree(const struct pathspec *pathspec,
 195                           struct object_id *tree_oid,
 196                           int intent_to_add)
 197 {
 198         struct diff_options opt;
 199
 200         memset(&opt, 0, sizeof(opt));
 201         copy_pathspec(&opt.pathspec, pathspec);
 202         opt.output_format = DIFF_FORMAT_CALLBACK;
 203         opt.format_callback = update_index_from_diff;
 204         opt.format_callback_data = &intent_to_add;
 205         opt.flags.override_submodule_config = 1;
 206         opt.flags.recursive = 1;
 207         opt.repo = the_repository;
 208         opt.change = diff_change;
 209         opt.add_remove = diff_addremove;
 210
 211         if (pathspec->nr && pathspec_needs_expanded_index(the_repository->index, pathspec))
 212                 ensure_full_index(the_repository->index);
 213
 214         if (do_diff_cache(tree_oid, &opt))
 215                 return 1;
 216         diffcore_std(&opt);
 217         diff_flush(&opt);
 218
 219         return 0;
 220 }
 221
 222 static void set_reflog_message(struct strbuf *sb, const char *action,
 223                                const char *rev)
 224 {
 225         const char *rla = getenv("GIT_REFLOG_ACTION");
 226
 227         strbuf_reset(sb);
 228         if (rla)
 229                 strbuf_addf(sb, "%s: %s", rla, action);
 230         else if (rev)
 231                 strbuf_addf(sb, "reset: moving to %s", rev);
 232         else
 233                 strbuf_addf(sb, "reset: %s", action);
 234 }
 235
 236 static void die_if_unmerged_cache(int reset_type)
 237 {
 238         if (is_merge() || unmerged_index(the_repository->index))
 239                 die(_("Cannot do a %s reset in the middle of a merge."),
 240                     _(reset_type_names[reset_type]));
 241
 242 }
 243
 244 static void parse_args(struct pathspec *pathspec,
 245                        const char **argv, const char *prefix,
 246                        int patch_mode,
 247                        const char **rev_ret)
 248 {
 249         const char *rev = "HEAD";
 250         struct object_id unused;
 251         /*
 252          * Possible arguments are:
 253          *
 254          * git reset [-opts] [<rev>]
 255          * git reset [-opts] <tree> [<paths>...]
 256          * git reset [-opts] <tree> -- [<paths>...]
 257          * git reset [-opts] -- [<paths>...]
 258          * git reset [-opts] <paths>...
 259          *
 260          * At this point, argv points immediately after [-opts].
 261          */
 262
 263         if (argv[0]) {
 264                 if (!strcmp(argv[0], "--")) {
 265                         argv++; /* reset to HEAD, possibly with paths */
 266                 } else if (argv[1] && !strcmp(argv[1], "--")) {
 267                         rev = argv[0];
 268                         argv += 2;
 269                 }
 270                 /*
 271                  * Otherwise, argv[0] could be either <rev> or <paths> and
 272                  * has to be unambiguous. If there is a single argument, it
 273                  * can not be a tree
 274                  */
 275                 else if ((!argv[1] && !repo_get_oid_committish(the_repository, argv[0], &unused)) ||
 276                          (argv[1] && !repo_get_oid_treeish(the_repository, argv[0], &unused))) {
 277                         /*
 278                          * Ok, argv[0] looks like a commit/tree; it should not
 279                          * be a filename.
 280                          */
 281                         verify_non_filename(prefix, argv[0]);
 282                         rev = *argv++;
 283                 } else {
 284                         /* Otherwise we treat this as a filename */
 285                         verify_filename(prefix, argv[0], 1);
 286                 }
 287         }
 288
 289         /* treat '@' as a shortcut for 'HEAD' */
 290         *rev_ret = !strcmp("@", rev) ? "HEAD" : rev;
 291
 292         parse_pathspec(pathspec, 0,
 293                        PATHSPEC_PREFER_FULL |
 294                        (patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0),
 295                        prefix, argv);
 296 }
 297
 298 static int reset_refs(const char *rev, const struct object_id *oid)
 299 {
 300         int update_ref_status;
 301         struct strbuf msg = STRBUF_INIT;
 302         struct object_id *orig = NULL, oid_orig,
 303                 *old_orig = NULL, oid_old_orig;
 304
 305         if (!repo_get_oid(the_repository, "ORIG_HEAD", &oid_old_orig))
 306                 old_orig = &oid_old_orig;
 307         if (!repo_get_oid(the_repository, "HEAD", &oid_orig)) {
 308                 orig = &oid_orig;
 309                 set_reflog_message(&msg, "updating ORIG_HEAD", NULL);
 310                 update_ref(msg.buf, "ORIG_HEAD", orig, old_orig, 0,
 311                            UPDATE_REFS_MSG_ON_ERR);
 312         } else if (old_orig)
 313                 delete_ref(NULL, "ORIG_HEAD", old_orig, 0);
 314         set_reflog_message(&msg, "updating HEAD", rev);
 315         update_ref_status = update_ref(msg.buf, "HEAD", oid, orig, 0,
 316                                        UPDATE_REFS_MSG_ON_ERR);
 317         strbuf_release(&msg);
 318         return update_ref_status;
 319 }
 320
 321 static int git_reset_config(const char *var, const char *value,
 322                             const struct config_context *ctx, void *cb)
 323 {
 324         if (!strcmp(var, "submodule.recurse"))
 325                 return git_default_submodule_config(var, value, cb);
 326
 327         return git_default_config(var, value, ctx, cb);
 328 }
 329
 330 int cmd_reset(int argc, const char **argv, const char *prefix)
 331 {
 332         int reset_type = NONE, update_ref_status = 0, quiet = 0;
 333         int no_refresh = 0;
 334         int patch_mode = 0, pathspec_file_nul = 0, unborn;
 335         const char *rev;
 336         char *pathspec_from_file = NULL;
 337         struct object_id oid;
 338         struct pathspec pathspec;
 339         int intent_to_add = 0;
 340         const struct option options[] = {
 341                 OPT__QUIET(&quiet, N_("be quiet, only report errors")),
 342                 OPT_BOOL(0, "no-refresh", &no_refresh,
 343                                 N_("skip refreshing the index after reset")),
 344                 OPT_SET_INT_F(0, "mixed", &reset_type,
 345                               N_("reset HEAD and index"),
 346                               MIXED, PARSE_OPT_NONEG),
 347                 OPT_SET_INT_F(0, "soft", &reset_type,
 348                               N_("reset only HEAD"),
 349                               SOFT, PARSE_OPT_NONEG),
 350                 OPT_SET_INT_F(0, "hard", &reset_type,
 351                               N_("reset HEAD, index and working tree"),
 352                               HARD, PARSE_OPT_NONEG),
 353                 OPT_SET_INT_F(0, "merge", &reset_type,
 354                               N_("reset HEAD, index and working tree"),
 355                               MERGE, PARSE_OPT_NONEG),
 356                 OPT_SET_INT_F(0, "keep", &reset_type,
 357                               N_("reset HEAD but keep local changes"),
 358                               KEEP, PARSE_OPT_NONEG),
 359                 OPT_CALLBACK_F(0, "recurse-submodules", NULL,
 360                                "reset", "control recursive updating of submodules",
 361                                PARSE_OPT_OPTARG,
 362                                option_parse_recurse_submodules_worktree_updater),
 363                 OPT_BOOL('p', "patch", &patch_mode, N_("select hunks interactively")),
 364                 OPT_BOOL('N', "intent-to-add", &intent_to_add,
 365                                 N_("record only the fact that removed paths will be added later")),
 366                 OPT_PATHSPEC_FROM_FILE(&pathspec_from_file),
 367                 OPT_PATHSPEC_FILE_NUL(&pathspec_file_nul),
 368                 OPT_END()
 369         };
 370
 371         git_config(git_reset_config, NULL);
 372
 373         argc = parse_options(argc, argv, prefix, options, git_reset_usage,
 374                                                 PARSE_OPT_KEEP_DASHDASH);
 375         parse_args(&pathspec, argv, prefix, patch_mode, &rev);
 376
 377         if (pathspec_from_file) {
 378                 if (patch_mode)
 379                         die(_("options '%s' and '%s' cannot be used together"), "--pathspec-from-file", "--patch");
 380
 381                 if (pathspec.nr)
 382                         die(_("'%s' and pathspec arguments cannot be used together"), "--pathspec-from-file");
 383
 384                 parse_pathspec_file(&pathspec, 0,
 385                                     PATHSPEC_PREFER_FULL,
 386                                     prefix, pathspec_from_file, pathspec_file_nul);
 387         } else if (pathspec_file_nul) {
 388                 die(_("the option '%s' requires '%s'"), "--pathspec-file-nul", "--pathspec-from-file");
 389         }
 390
 391         unborn = !strcmp(rev, "HEAD") && repo_get_oid(the_repository, "HEAD",
 392                                                       &oid);
 393         if (unborn) {
 394                 /* reset on unborn branch: treat as reset to empty tree */
 395                 oidcpy(&oid, the_hash_algo->empty_tree);
 396         } else if (!pathspec.nr && !patch_mode) {
 397                 struct commit *commit;
 398                 if (repo_get_oid_committish(the_repository, rev, &oid))
 399                         die(_("Failed to resolve '%s' as a valid revision."), rev);
 400                 commit = lookup_commit_reference(the_repository, &oid);
 401                 if (!commit)
 402                         die(_("Could not parse object '%s'."), rev);
 403                 oidcpy(&oid, &commit->object.oid);
 404         } else {
 405                 struct tree *tree;
 406                 if (repo_get_oid_treeish(the_repository, rev, &oid))
 407                         die(_("Failed to resolve '%s' as a valid tree."), rev);
 408                 tree = parse_tree_indirect(&oid);
 409                 if (!tree)
 410                         die(_("Could not parse object '%s'."), rev);
 411                 oidcpy(&oid, &tree->object.oid);
 412         }
 413
 414         if (patch_mode) {
 415                 if (reset_type != NONE)
 416                         die(_("options '%s' and '%s' cannot be used together"), "--patch", "--{hard,mixed,soft}");
 417                 trace2_cmd_mode("patch-interactive");
 418                 update_ref_status = !!run_add_p(the_repository, ADD_P_RESET, rev,
 419                                    &pathspec);
 420                 goto cleanup;
 421         }
 422
 423         /* git reset tree [--] paths... can be used to
 424          * load chosen paths from the tree into the index without
 425          * affecting the working tree nor HEAD. */
 426         if (pathspec.nr) {
 427                 if (reset_type == MIXED)
 428                         warning(_("--mixed with paths is deprecated; use 'git reset -- <paths>' instead."));
 429                 else if (reset_type != NONE)
 430                         die(_("Cannot do %s reset with paths."),
 431                                         _(reset_type_names[reset_type]));
 432         }
 433         if (reset_type == NONE)
 434                 reset_type = MIXED; /* by default */
 435
 436         if (pathspec.nr)
 437                 trace2_cmd_mode("path");
 438         else
 439                 trace2_cmd_mode(reset_type_names[reset_type]);
 440
 441         if (reset_type != SOFT && (reset_type != MIXED || get_git_work_tree()))
 442                 setup_work_tree();
 443
 444         if (reset_type == MIXED && is_bare_repository())
 445                 die(_("%s reset is not allowed in a bare repository"),
 446                     _(reset_type_names[reset_type]));
 447
 448         if (intent_to_add && reset_type != MIXED)
 449                 die(_("the option '%s' requires '%s'"), "-N", "--mixed");
 450
 451         prepare_repo_settings(the_repository);
 452         the_repository->settings.command_requires_full_index = 0;
 453
 454         if (repo_read_index(the_repository) < 0)
 455                 die(_("index file corrupt"));
 456
 457         /* Soft reset does not touch the index file nor the working tree
 458          * at all, but requires them in a good order.  Other resets reset
 459          * the index file to the tree object we are switching to. */
 460         if (reset_type == SOFT || reset_type == KEEP)
 461                 die_if_unmerged_cache(reset_type);
 462
 463         if (reset_type != SOFT) {
 464                 struct lock_file lock = LOCK_INIT;
 465                 repo_hold_locked_index(the_repository, &lock,
 466                                        LOCK_DIE_ON_ERROR);
 467                 if (reset_type == MIXED) {
 468                         int flags = quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN;
 469                         if (read_from_tree(&pathspec, &oid, intent_to_add)) {
 470                                 update_ref_status = 1;
 471                                 goto cleanup;
 472                         }
 473                         the_repository->index->updated_skipworktree = 1;
 474                         if (!no_refresh && get_git_work_tree()) {
 475                                 uint64_t t_begin, t_delta_in_ms;
 476
 477                                 t_begin = getnanotime();
 478                                 refresh_index(the_repository->index, flags, NULL, NULL,
 479                                               _("Unstaged changes after reset:"));
 480                                 t_delta_in_ms = (getnanotime() - t_begin) / 1000000;
 481                                 if (!quiet && advice_enabled(ADVICE_RESET_NO_REFRESH_WARNING) && t_delta_in_ms > REFRESH_INDEX_DELAY_WARNING_IN_MS) {
 482                                         advise(_("It took %.2f seconds to refresh the index after reset.  You can use\n"
 483                                                  "'--no-refresh' to avoid this."), t_delta_in_ms / 1000.0);
 484                                 }
 485                         }
 486                 } else {
 487                         struct object_id dummy;
 488                         char *ref = NULL;
 489                         int err;
 490
 491                         repo_dwim_ref(the_repository, rev, strlen(rev),
 492                                       &dummy, &ref, 0);
 493                         if (ref && !starts_with(ref, "refs/"))
 494                                 FREE_AND_NULL(ref);
 495
 496                         err = reset_index(ref, &oid, reset_type, quiet);
 497                         if (reset_type == KEEP && !err)
 498                                 err = reset_index(ref, &oid, MIXED, quiet);
 499                         if (err)
 500                                 die(_("Could not reset index file to revision '%s'."), rev);
 501                         free(ref);
 502                 }
 503
 504                 if (write_locked_index(the_repository->index, &lock, COMMIT_LOCK))
 505                         die(_("Could not write new index file."));
 506         }
 507
 508         if (!pathspec.nr && !unborn) {
 509                 /* Any resets without paths update HEAD to the head being
 510                  * switched to, saving the previous head in ORIG_HEAD before. */
 511                 update_ref_status = reset_refs(rev, &oid);
 512
 513                 if (reset_type == HARD && !update_ref_status && !quiet)
 514                         print_new_head_line(lookup_commit_reference(the_repository, &oid));
 515         }
 516         if (!pathspec.nr)
 517                 remove_branch_state(the_repository, 0);
 518
 519         discard_index(the_repository->index);
 520
 521 cleanup:
 522         clear_pathspec(&pathspec);
 523         free(pathspec_from_file);
 524         return update_ref_status;
 525 }