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