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