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