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