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 #include "builtin.h"
  11 #include "config.h"
  12 #include "lockfile.h"
  13 #include "tag.h"
  14 #include "object.h"
  15 #include "pretty.h"
  16 #include "run-command.h"
  17 #include "refs.h"
  18 #include "diff.h"
  19 #include "diffcore.h"
  20 #include "tree.h"
  21 #include "branch.h"
  22 #include "parse-options.h"
  23 #include "unpack-trees.h"
  24 #include "cache-tree.h"
  25 #include "submodule.h"
  26 #include "submodule-config.h"
  27
  28 #define REFRESH_INDEX_DELAY_WARNING_IN_MS (2 * 1000)
  29
  30 static const char * const git_reset_usage[] = {
  31         N_("git reset [--mixed | --soft | --hard | --merge | --keep] [-q] [<commit>]"),
  32         N_("git reset [-q] [<tree-ish>] [--] <paths>..."),
  33         N_("git reset --patch [<tree-ish>] [--] [<paths>...]"),
  34         NULL
  35 };
  36
  37 enum reset_type { MIXED, SOFT, HARD, MERGE, KEEP, NONE };
  38 static const char *reset_type_names[] = {
  39         N_("mixed"), N_("soft"), N_("hard"), N_("merge"), N_("keep"), NULL
  40 };
  41
  42 static inline int is_merge(void)
  43 {
  44         return !access(git_path_merge_head(the_repository), F_OK);
  45 }
  46
  47 static int reset_index(const struct object_id *oid, int reset_type, int quiet)
  48 {
  49         int i, nr = 0;
  50         struct tree_desc desc[2];
  51         struct tree *tree;
  52         struct unpack_trees_options opts;
  53         int ret = -1;
  54
  55         memset(&opts, 0, sizeof(opts));
  56         opts.head_idx = 1;
  57         opts.src_index = &the_index;
  58         opts.dst_index = &the_index;
  59         opts.fn = oneway_merge;
  60         opts.merge = 1;
  61         if (!quiet)
  62                 opts.verbose_update = 1;
  63         switch (reset_type) {
  64         case KEEP:
  65         case MERGE:
  66                 opts.update = 1;
  67                 break;
  68         case HARD:
  69                 opts.update = 1;
  70                 /* fallthrough */
  71         default:
  72                 opts.reset = 1;
  73         }
  74
  75         read_cache_unmerged();
  76
  77         if (reset_type == KEEP) {
  78                 struct object_id head_oid;
  79                 if (get_oid("HEAD", &head_oid))
  80                         return error(_("You do not have a valid HEAD."));
  81                 if (!fill_tree_descriptor(desc + nr, &head_oid))
  82                         return error(_("Failed to find tree of HEAD."));
  83                 nr++;
  84                 opts.fn = twoway_merge;
  85         }
  86
  87         if (!fill_tree_descriptor(desc + nr, oid)) {
  88                 error(_("Failed to find tree of %s."), oid_to_hex(oid));
  89                 goto out;
  90         }
  91         nr++;
  92
  93         if (unpack_trees(nr, desc, &opts))
  94                 goto out;
  95
  96         if (reset_type == MIXED || reset_type == HARD) {
  97                 tree = parse_tree_indirect(oid);
  98                 prime_cache_tree(the_repository, the_repository->index, tree);
  99         }
 100
 101         ret = 0;
 102
 103 out:
 104         for (i = 0; i < nr; i++)
 105                 free((void *)desc[i].buffer);
 106         return ret;
 107 }
 108
 109 static void print_new_head_line(struct commit *commit)
 110 {
 111         struct strbuf buf = STRBUF_INIT;
 112
 113         printf(_("HEAD is now at %s"),
 114                 find_unique_abbrev(&commit->object.oid, DEFAULT_ABBREV));
 115
 116         pp_commit_easy(CMIT_FMT_ONELINE, commit, &buf);
 117         if (buf.len > 0)
 118                 printf(" %s", buf.buf);
 119         putchar('\n');
 120         strbuf_release(&buf);
 121 }
 122
 123 static void update_index_from_diff(struct diff_queue_struct *q,
 124                 struct diff_options *opt, void *data)
 125 {
 126         int i;
 127         int intent_to_add = *(int *)data;
 128
 129         for (i = 0; i < q->nr; i++) {
 130                 struct diff_filespec *one = q->queue[i]->one;
 131                 int is_missing = !(one->mode && !is_null_oid(&one->oid));
 132                 struct cache_entry *ce;
 133
 134                 if (is_missing && !intent_to_add) {
 135                         remove_file_from_cache(one->path);
 136                         continue;
 137                 }
 138
 139                 ce = make_cache_entry(&the_index, one->mode, &one->oid, one->path,
 140                                       0, 0);
 141                 if (!ce)
 142                         die(_("make_cache_entry failed for path '%s'"),
 143                             one->path);
 144                 if (is_missing) {
 145                         ce->ce_flags |= CE_INTENT_TO_ADD;
 146                         set_object_name_for_intent_to_add_entry(ce);
 147                 }
 148                 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
 149         }
 150 }
 151
 152 static int read_from_tree(const struct pathspec *pathspec,
 153                           struct object_id *tree_oid,
 154                           int intent_to_add)
 155 {
 156         struct diff_options opt;
 157
 158         memset(&opt, 0, sizeof(opt));
 159         copy_pathspec(&opt.pathspec, pathspec);
 160         opt.output_format = DIFF_FORMAT_CALLBACK;
 161         opt.format_callback = update_index_from_diff;
 162         opt.format_callback_data = &intent_to_add;
 163         opt.flags.override_submodule_config = 1;
 164         opt.repo = the_repository;
 165
 166         if (do_diff_cache(tree_oid, &opt))
 167                 return 1;
 168         diffcore_std(&opt);
 169         diff_flush(&opt);
 170         clear_pathspec(&opt.pathspec);
 171
 172         return 0;
 173 }
 174
 175 static void set_reflog_message(struct strbuf *sb, const char *action,
 176                                const char *rev)
 177 {
 178         const char *rla = getenv("GIT_REFLOG_ACTION");
 179
 180         strbuf_reset(sb);
 181         if (rla)
 182                 strbuf_addf(sb, "%s: %s", rla, action);
 183         else if (rev)
 184                 strbuf_addf(sb, "reset: moving to %s", rev);
 185         else
 186                 strbuf_addf(sb, "reset: %s", action);
 187 }
 188
 189 static void die_if_unmerged_cache(int reset_type)
 190 {
 191         if (is_merge() || unmerged_cache())
 192                 die(_("Cannot do a %s reset in the middle of a merge."),
 193                     _(reset_type_names[reset_type]));
 194
 195 }
 196
 197 static void parse_args(struct pathspec *pathspec,
 198                        const char **argv, const char *prefix,
 199                        int patch_mode,
 200                        const char **rev_ret)
 201 {
 202         const char *rev = "HEAD";
 203         struct object_id unused;
 204         /*
 205          * Possible arguments are:
 206          *
 207          * git reset [-opts] [<rev>]
 208          * git reset [-opts] <tree> [<paths>...]
 209          * git reset [-opts] <tree> -- [<paths>...]
 210          * git reset [-opts] -- [<paths>...]
 211          * git reset [-opts] <paths>...
 212          *
 213          * At this point, argv points immediately after [-opts].
 214          */
 215
 216         if (argv[0]) {
 217                 if (!strcmp(argv[0], "--")) {
 218                         argv++; /* reset to HEAD, possibly with paths */
 219                 } else if (argv[1] && !strcmp(argv[1], "--")) {
 220                         rev = argv[0];
 221                         argv += 2;
 222                 }
 223                 /*
 224                  * Otherwise, argv[0] could be either <rev> or <paths> and
 225                  * has to be unambiguous. If there is a single argument, it
 226                  * can not be a tree
 227                  */
 228                 else if ((!argv[1] && !get_oid_committish(argv[0], &unused)) ||
 229                          (argv[1] && !get_oid_treeish(argv[0], &unused))) {
 230                         /*
 231                          * Ok, argv[0] looks like a commit/tree; it should not
 232                          * be a filename.
 233                          */
 234                         verify_non_filename(prefix, argv[0]);
 235                         rev = *argv++;
 236                 } else {
 237                         /* Otherwise we treat this as a filename */
 238                         verify_filename(prefix, argv[0], 1);
 239                 }
 240         }
 241         *rev_ret = rev;
 242
 243         if (read_cache() < 0)
 244                 die(_("index file corrupt"));
 245
 246         parse_pathspec(pathspec, 0,
 247                        PATHSPEC_PREFER_FULL |
 248                        (patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0),
 249                        prefix, argv);
 250 }
 251
 252 static int reset_refs(const char *rev, const struct object_id *oid)
 253 {
 254         int update_ref_status;
 255         struct strbuf msg = STRBUF_INIT;
 256         struct object_id *orig = NULL, oid_orig,
 257                 *old_orig = NULL, oid_old_orig;
 258
 259         if (!get_oid("ORIG_HEAD", &oid_old_orig))
 260                 old_orig = &oid_old_orig;
 261         if (!get_oid("HEAD", &oid_orig)) {
 262                 orig = &oid_orig;
 263                 set_reflog_message(&msg, "updating ORIG_HEAD", NULL);
 264                 update_ref(msg.buf, "ORIG_HEAD", orig, old_orig, 0,
 265                            UPDATE_REFS_MSG_ON_ERR);
 266         } else if (old_orig)
 267                 delete_ref(NULL, "ORIG_HEAD", old_orig, 0);
 268         set_reflog_message(&msg, "updating HEAD", rev);
 269         update_ref_status = update_ref(msg.buf, "HEAD", oid, orig, 0,
 270                                        UPDATE_REFS_MSG_ON_ERR);
 271         strbuf_release(&msg);
 272         return update_ref_status;
 273 }
 274
 275 static int git_reset_config(const char *var, const char *value, void *cb)
 276 {
 277         if (!strcmp(var, "submodule.recurse"))
 278                 return git_default_submodule_config(var, value, cb);
 279
 280         return git_default_config(var, value, cb);
 281 }
 282
 283 int cmd_reset(int argc, const char **argv, const char *prefix)
 284 {
 285         int reset_type = NONE, update_ref_status = 0, quiet = 0;
 286         int patch_mode = 0, unborn;
 287         const char *rev;
 288         struct object_id oid;
 289         struct pathspec pathspec;
 290         int intent_to_add = 0;
 291         const struct option options[] = {
 292                 OPT__QUIET(&quiet, N_("be quiet, only report errors")),
 293                 OPT_SET_INT(0, "mixed", &reset_type,
 294                                                 N_("reset HEAD and index"), MIXED),
 295                 OPT_SET_INT(0, "soft", &reset_type, N_("reset only HEAD"), SOFT),
 296                 OPT_SET_INT(0, "hard", &reset_type,
 297                                 N_("reset HEAD, index and working tree"), HARD),
 298                 OPT_SET_INT(0, "merge", &reset_type,
 299                                 N_("reset HEAD, index and working tree"), MERGE),
 300                 OPT_SET_INT(0, "keep", &reset_type,
 301                                 N_("reset HEAD but keep local changes"), KEEP),
 302                 { OPTION_CALLBACK, 0, "recurse-submodules", NULL,
 303                             "reset", "control recursive updating of submodules",
 304                             PARSE_OPT_OPTARG, option_parse_recurse_submodules_worktree_updater },
 305                 OPT_BOOL('p', "patch", &patch_mode, N_("select hunks interactively")),
 306                 OPT_BOOL('N', "intent-to-add", &intent_to_add,
 307                                 N_("record only the fact that removed paths will be added later")),
 308                 OPT_END()
 309         };
 310
 311         git_config(git_reset_config, NULL);
 312         git_config_get_bool("reset.quiet", &quiet);
 313
 314         argc = parse_options(argc, argv, prefix, options, git_reset_usage,
 315                                                 PARSE_OPT_KEEP_DASHDASH);
 316         parse_args(&pathspec, argv, prefix, patch_mode, &rev);
 317
 318         unborn = !strcmp(rev, "HEAD") && get_oid("HEAD", &oid);
 319         if (unborn) {
 320                 /* reset on unborn branch: treat as reset to empty tree */
 321                 oidcpy(&oid, the_hash_algo->empty_tree);
 322         } else if (!pathspec.nr) {
 323                 struct commit *commit;
 324                 if (get_oid_committish(rev, &oid))
 325                         die(_("Failed to resolve '%s' as a valid revision."), rev);
 326                 commit = lookup_commit_reference(the_repository, &oid);
 327                 if (!commit)
 328                         die(_("Could not parse object '%s'."), rev);
 329                 oidcpy(&oid, &commit->object.oid);
 330         } else {
 331                 struct tree *tree;
 332                 if (get_oid_treeish(rev, &oid))
 333                         die(_("Failed to resolve '%s' as a valid tree."), rev);
 334                 tree = parse_tree_indirect(&oid);
 335                 if (!tree)
 336                         die(_("Could not parse object '%s'."), rev);
 337                 oidcpy(&oid, &tree->object.oid);
 338         }
 339
 340         if (patch_mode) {
 341                 if (reset_type != NONE)
 342                         die(_("--patch is incompatible with --{hard,mixed,soft}"));
 343                 return run_add_interactive(rev, "--patch=reset", &pathspec);
 344         }
 345
 346         /* git reset tree [--] paths... can be used to
 347          * load chosen paths from the tree into the index without
 348          * affecting the working tree nor HEAD. */
 349         if (pathspec.nr) {
 350                 if (reset_type == MIXED)
 351                         warning(_("--mixed with paths is deprecated; use 'git reset -- <paths>' instead."));
 352                 else if (reset_type != NONE)
 353                         die(_("Cannot do %s reset with paths."),
 354                                         _(reset_type_names[reset_type]));
 355         }
 356         if (reset_type == NONE)
 357                 reset_type = MIXED; /* by default */
 358
 359         if (reset_type != SOFT && (reset_type != MIXED || get_git_work_tree()))
 360                 setup_work_tree();
 361
 362         if (reset_type == MIXED && is_bare_repository())
 363                 die(_("%s reset is not allowed in a bare repository"),
 364                     _(reset_type_names[reset_type]));
 365
 366         if (intent_to_add && reset_type != MIXED)
 367                 die(_("-N can only be used with --mixed"));
 368
 369         /* Soft reset does not touch the index file nor the working tree
 370          * at all, but requires them in a good order.  Other resets reset
 371          * the index file to the tree object we are switching to. */
 372         if (reset_type == SOFT || reset_type == KEEP)
 373                 die_if_unmerged_cache(reset_type);
 374
 375         if (reset_type != SOFT) {
 376                 struct lock_file lock = LOCK_INIT;
 377                 hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
 378                 if (reset_type == MIXED) {
 379                         int flags = quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN;
 380                         if (read_from_tree(&pathspec, &oid, intent_to_add))
 381                                 return 1;
 382                         if (!quiet && get_git_work_tree()) {
 383                                 uint64_t t_begin, t_delta_in_ms;
 384
 385                                 t_begin = getnanotime();
 386                                 refresh_index(&the_index, flags, NULL, NULL,
 387                                               _("Unstaged changes after reset:"));
 388                                 t_delta_in_ms = (getnanotime() - t_begin) / 1000000;
 389                                 if (advice_reset_quiet_warning && t_delta_in_ms > REFRESH_INDEX_DELAY_WARNING_IN_MS) {
 390                                         printf(_("\nIt took %.2f seconds to enumerate unstaged changes after reset.  You can\n"
 391                                                 "use '--quiet' to avoid this.  Set the config setting reset.quiet to true\n"
 392                                                 "to make this the default.\n"), t_delta_in_ms / 1000.0);
 393                                 }
 394                         }
 395                 } else {
 396                         int err = reset_index(&oid, reset_type, quiet);
 397                         if (reset_type == KEEP && !err)
 398                                 err = reset_index(&oid, MIXED, quiet);
 399                         if (err)
 400                                 die(_("Could not reset index file to revision '%s'."), rev);
 401                 }
 402
 403                 if (write_locked_index(&the_index, &lock, COMMIT_LOCK))
 404                         die(_("Could not write new index file."));
 405         }
 406
 407         if (!pathspec.nr && !unborn) {
 408                 /* Any resets without paths update HEAD to the head being
 409                  * switched to, saving the previous head in ORIG_HEAD before. */
 410                 update_ref_status = reset_refs(rev, &oid);
 411
 412                 if (reset_type == HARD && !update_ref_status && !quiet)
 413                         print_new_head_line(lookup_commit_reference(the_repository, &oid));
 414         }
 415         if (!pathspec.nr)
 416                 remove_branch_state(the_repository);
 417
 418         return update_ref_status;
 419 }