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