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