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