git.oblomov.eu Git - git/blob - 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 "lockfile.h"
  12 #include "tag.h"
  13 #include "object.h"
  14 #include "commit.h"
  15 #include "run-command.h"
  16 #include "refs.h"
  17 #include "diff.h"
  18 #include "diffcore.h"
  19 #include "tree.h"
  20 #include "branch.h"
  21 #include "parse-options.h"
  22 #include "unpack-trees.h"
  23 #include "cache-tree.h"
  24
  25 static const char * const git_reset_usage[] = {
  26         N_("git reset [--mixed | --soft | --hard | --merge | --keep] [-q] [<commit>]"),
  27         N_("git reset [--stage | --work | --keep] [-q] [<commit>]"),
  28         N_("git reset [-q] <tree-ish> [--] <paths>..."),
  29         N_("git reset --patch [<tree-ish>] [--] [<paths>...]"),
  30         NULL
  31 };
  32
  33 enum reset_type { MIXED, SOFT, HARD, MERGE, KEEP, NONE };
  34 static const char *reset_type_names[] = {
  35         N_("mixed"), N_("soft"), N_("hard"), N_("merge"), N_("keep"), NULL
  36 };
  37
  38 static inline int is_merge(void)
  39 {
  40         return !access(git_path_merge_head(), F_OK);
  41 }
  42
  43 static int reset_index(const unsigned char *sha1, int reset_type, int quiet)
  44 {
  45         int nr = 1;
  46         struct tree_desc desc[2];
  47         struct tree *tree;
  48         struct unpack_trees_options opts;
  49
  50         memset(&opts, 0, sizeof(opts));
  51         opts.head_idx = 1;
  52         opts.src_index = &the_index;
  53         opts.dst_index = &the_index;
  54         opts.fn = oneway_merge;
  55         opts.merge = 1;
  56         if (!quiet)
  57                 opts.verbose_update = 1;
  58         switch (reset_type) {
  59         case KEEP:
  60         case MERGE:
  61                 opts.update = 1;
  62                 break;
  63         case HARD:
  64                 opts.update = 1;
  65                 /* fallthrough */
  66         default:
  67                 opts.reset = 1;
  68         }
  69
  70         read_cache_unmerged();
  71
  72         if (reset_type == KEEP) {
  73                 unsigned char head_sha1[20];
  74                 if (get_sha1("HEAD", head_sha1))
  75                         return error(_("You do not have a valid HEAD."));
  76                 if (!fill_tree_descriptor(desc, head_sha1))
  77                         return error(_("Failed to find tree of HEAD."));
  78                 nr++;
  79                 opts.fn = twoway_merge;
  80         }
  81
  82         if (!fill_tree_descriptor(desc + nr - 1, sha1))
  83                 return error(_("Failed to find tree of %s."), sha1_to_hex(sha1));
  84         if (unpack_trees(nr, desc, &opts))
  85                 return -1;
  86
  87         if (reset_type == MIXED || reset_type == HARD) {
  88                 tree = parse_tree_indirect(sha1);
  89                 prime_cache_tree(&the_index, tree);
  90         }
  91
  92         return 0;
  93 }
  94
  95 static void print_new_head_line(struct commit *commit)
  96 {
  97         const char *hex, *body;
  98         const char *msg;
  99
 100         hex = find_unique_abbrev(commit->object.oid.hash, DEFAULT_ABBREV);
 101         printf(_("HEAD is now at %s"), hex);
 102         msg = logmsg_reencode(commit, NULL, get_log_output_encoding());
 103         body = strstr(msg, "\n\n");
 104         if (body) {
 105                 const char *eol;
 106                 size_t len;
 107                 body += 2;
 108                 eol = strchr(body, '\n');
 109                 len = eol ? eol - body : strlen(body);
 110                 printf(" %.*s\n", (int) len, body);
 111         }
 112         else
 113                 printf("\n");
 114         unuse_commit_buffer(commit, msg);
 115 }
 116
 117 static void update_index_from_diff(struct diff_queue_struct *q,
 118                 struct diff_options *opt, void *data)
 119 {
 120         int i;
 121         int intent_to_add = *(int *)data;
 122
 123         for (i = 0; i < q->nr; i++) {
 124                 struct diff_filespec *one = q->queue[i]->one;
 125                 int is_missing = !(one->mode && !is_null_sha1(one->sha1));
 126                 struct cache_entry *ce;
 127
 128                 if (is_missing && !intent_to_add) {
 129                         remove_file_from_cache(one->path);
 130                         continue;
 131                 }
 132
 133                 ce = make_cache_entry(one->mode, one->sha1, one->path,
 134                                       0, 0);
 135                 if (!ce)
 136                         die(_("make_cache_entry failed for path '%s'"),
 137                             one->path);
 138                 if (is_missing) {
 139                         ce->ce_flags |= CE_INTENT_TO_ADD;
 140                         set_object_name_for_intent_to_add_entry(ce);
 141                 }
 142                 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
 143         }
 144 }
 145
 146 static int read_from_tree(const struct pathspec *pathspec,
 147                           unsigned char *tree_sha1,
 148                           int intent_to_add)
 149 {
 150         struct diff_options opt;
 151
 152         memset(&opt, 0, sizeof(opt));
 153         copy_pathspec(&opt.pathspec, pathspec);
 154         opt.output_format = DIFF_FORMAT_CALLBACK;
 155         opt.format_callback = update_index_from_diff;
 156         opt.format_callback_data = &intent_to_add;
 157
 158         if (do_diff_cache(tree_sha1, &opt))
 159                 return 1;
 160         diffcore_std(&opt);
 161         diff_flush(&opt);
 162         free_pathspec(&opt.pathspec);
 163
 164         return 0;
 165 }
 166
 167 static void set_reflog_message(struct strbuf *sb, const char *action,
 168                                const char *rev)
 169 {
 170         const char *rla = getenv("GIT_REFLOG_ACTION");
 171
 172         strbuf_reset(sb);
 173         if (rla)
 174                 strbuf_addf(sb, "%s: %s", rla, action);
 175         else if (rev)
 176                 strbuf_addf(sb, "reset: moving to %s", rev);
 177         else
 178                 strbuf_addf(sb, "reset: %s", action);
 179 }
 180
 181 static void die_if_unmerged_cache(int reset_type)
 182 {
 183         if (is_merge() || unmerged_cache())
 184                 die(_("Cannot do a %s reset in the middle of a merge."),
 185                     _(reset_type_names[reset_type]));
 186
 187 }
 188
 189 static void parse_args(struct pathspec *pathspec,
 190                        const char **argv, const char *prefix,
 191                        int patch_mode,
 192                        const char **rev_ret)
 193 {
 194         const char *rev = "HEAD";
 195         unsigned char unused[20];
 196         /*
 197          * Possible arguments are:
 198          *
 199          * git reset [-opts] [<rev>]
 200          * git reset [-opts] <tree> [<paths>...]
 201          * git reset [-opts] <tree> -- [<paths>...]
 202          * git reset [-opts] -- [<paths>...]
 203          * git reset [-opts] <paths>...
 204          *
 205          * At this point, argv points immediately after [-opts].
 206          */
 207
 208         if (argv[0]) {
 209                 if (!strcmp(argv[0], "--")) {
 210                         argv++; /* reset to HEAD, possibly with paths */
 211                 } else if (argv[1] && !strcmp(argv[1], "--")) {
 212                         rev = argv[0];
 213                         argv += 2;
 214                 }
 215                 /*
 216                  * Otherwise, argv[0] could be either <rev> or <paths> and
 217                  * has to be unambiguous. If there is a single argument, it
 218                  * can not be a tree
 219                  */
 220                 else if ((!argv[1] && !get_sha1_committish(argv[0], unused)) ||
 221                          (argv[1] && !get_sha1_treeish(argv[0], unused))) {
 222                         /*
 223                          * Ok, argv[0] looks like a commit/tree; it should not
 224                          * be a filename.
 225                          */
 226                         verify_non_filename(prefix, argv[0]);
 227                         rev = *argv++;
 228                 } else {
 229                         /* Otherwise we treat this as a filename */
 230                         verify_filename(prefix, argv[0], 1);
 231                 }
 232         }
 233         *rev_ret = rev;
 234
 235         if (read_cache() < 0)
 236                 die(_("index file corrupt"));
 237
 238         parse_pathspec(pathspec, 0,
 239                        PATHSPEC_PREFER_FULL |
 240                        PATHSPEC_STRIP_SUBMODULE_SLASH_CHEAP |
 241                        (patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0),
 242                        prefix, argv);
 243 }
 244
 245 static int reset_refs(const char *rev, const unsigned char *sha1)
 246 {
 247         int update_ref_status;
 248         struct strbuf msg = STRBUF_INIT;
 249         unsigned char *orig = NULL, sha1_orig[20],
 250                 *old_orig = NULL, sha1_old_orig[20];
 251
 252         if (!get_sha1("ORIG_HEAD", sha1_old_orig))
 253                 old_orig = sha1_old_orig;
 254         if (!get_sha1("HEAD", sha1_orig)) {
 255                 orig = sha1_orig;
 256                 set_reflog_message(&msg, "updating ORIG_HEAD", NULL);
 257                 update_ref(msg.buf, "ORIG_HEAD", orig, old_orig, 0,
 258                            UPDATE_REFS_MSG_ON_ERR);
 259         } else if (old_orig)
 260                 delete_ref("ORIG_HEAD", old_orig, 0);
 261         set_reflog_message(&msg, "updating HEAD", rev);
 262         update_ref_status = update_ref(msg.buf, "HEAD", sha1, orig, 0,
 263                                        UPDATE_REFS_MSG_ON_ERR);
 264         strbuf_release(&msg);
 265         return update_ref_status;
 266 }
 267
 268 int cmd_reset(int argc, const char **argv, const char *prefix)
 269 {
 270         int reset_type = NONE, update_ref_status = 0, quiet = 0;
 271         int stage = -1, working_tree = -1;
 272         int patch_mode = 0, unborn;
 273         const char *rev;
 274         struct object_id oid;
 275         struct pathspec pathspec;
 276         int intent_to_add = 0;
 277         const struct option options[] = {
 278                 OPT__QUIET(&quiet, N_("be quiet, only report errors")),
 279                 OPT_SET_INT(0, "mixed", &reset_type,
 280                                                 N_("reset HEAD and index"), MIXED),
 281                 OPT_SET_INT(0, "soft", &reset_type, N_("reset only HEAD"), SOFT),
 282                 OPT_SET_INT(0, "hard", &reset_type,
 283                                 N_("reset HEAD, index and working tree"), HARD),
 284                 OPT_SET_INT(0, "merge", &reset_type,
 285                                 N_("reset HEAD, index and working tree"), MERGE),
 286                 OPT_SET_INT(0, "keep", &reset_type,
 287                                 N_("reset HEAD but keep local changes"), KEEP),
 288                 OPT_BOOL(0, "stage", &stage, N_("reset index")),
 289                 OPT_BOOL(0, "work", &working_tree, N_("reset working tree")),
 290                 OPT_BOOL('p', "patch", &patch_mode, N_("select hunks interactively")),
 291                 OPT_BOOL('N', "intent-to-add", &intent_to_add,
 292                                 N_("record only the fact that removed paths will be added later")),
 293                 OPT_END()
 294         };
 295
 296         git_config(git_default_config, NULL);
 297
 298         argc = parse_options(argc, argv, prefix, options, git_reset_usage,
 299                                                 PARSE_OPT_KEEP_DASHDASH);
 300         parse_args(&pathspec, argv, prefix, patch_mode, &rev);
 301
 302         unborn = !strcmp(rev, "HEAD") && get_sha1("HEAD", oid.hash);
 303         if (unborn) {
 304                 /* reset on unborn branch: treat as reset to empty tree */
 305                 hashcpy(oid.hash, EMPTY_TREE_SHA1_BIN);
 306         } else if (!pathspec.nr) {
 307                 struct commit *commit;
 308                 if (get_sha1_committish(rev, oid.hash))
 309                         die(_("Failed to resolve '%s' as a valid revision."), rev);
 310                 commit = lookup_commit_reference(oid.hash);
 311                 if (!commit)
 312                         die(_("Could not parse object '%s'."), rev);
 313                 oidcpy(&oid, &commit->object.oid);
 314         } else {
 315                 struct tree *tree;
 316                 if (get_sha1_treeish(rev, oid.hash))
 317                         die(_("Failed to resolve '%s' as a valid tree."), rev);
 318                 tree = parse_tree_indirect(oid.hash);
 319                 if (!tree)
 320                         die(_("Could not parse object '%s'."), rev);
 321                 oidcpy(&oid, &tree->object.oid);
 322         }
 323
 324         if (stage >= 0 || working_tree >= 0) {
 325                 int keep = 0;
 326
 327                 if (reset_type == KEEP) {
 328                         if (working_tree == 1)
 329                                 die(_("--keep is incompatible with --work"));
 330                         keep = 1;
 331                 } else if (reset_type != NONE) {
 332                         die(_("--{stage,work} are incompatible with --{hard,mixed,soft,merge}"));
 333                 }
 334
 335                 if (working_tree == 1) {
 336                         if (stage == 0)
 337                                 die(_("--no-stage doesn't make sense with --work"));
 338                         reset_type = HARD;
 339                 } else {
 340                         if (stage == 1)
 341                                 reset_type = keep ? KEEP : NONE;
 342                         else
 343                                 reset_type = SOFT;
 344                 }
 345         }
 346
 347         if (patch_mode) {
 348                 if (reset_type != NONE)
 349                         die(_("--patch is incompatible with --{hard,mixed,soft}"));
 350                 return run_add_interactive(rev, "--patch=reset", &pathspec);
 351         }
 352
 353         /* git reset tree [--] paths... can be used to
 354          * load chosen paths from the tree into the index without
 355          * affecting the working tree nor HEAD. */
 356         if (pathspec.nr) {
 357                 if (reset_type == MIXED)
 358                         warning(_("--mixed with paths is deprecated; use 'git reset -- <paths>' instead."));
 359                 else if (reset_type != NONE)
 360                         die(_("Cannot do %s reset with paths."),
 361                                         _(reset_type_names[reset_type]));
 362         }
 363         if (reset_type == NONE)
 364                 reset_type = MIXED; /* by default */
 365
 366         if (reset_type != SOFT && (reset_type != MIXED || get_git_work_tree()))
 367                 setup_work_tree();
 368
 369         if (reset_type == MIXED && is_bare_repository())
 370                 die(_("%s reset is not allowed in a bare repository"),
 371                     _(reset_type_names[reset_type]));
 372
 373         if (intent_to_add && reset_type != MIXED)
 374                 die(_("-N can only be used with --mixed"));
 375
 376         /* Soft reset does not touch the index file nor the working tree
 377          * at all, but requires them in a good order.  Other resets reset
 378          * the index file to the tree object we are switching to. */
 379         if (reset_type == SOFT || reset_type == KEEP)
 380                 die_if_unmerged_cache(reset_type);
 381
 382         if (reset_type != SOFT) {
 383                 struct lock_file *lock = xcalloc(1, sizeof(*lock));
 384                 hold_locked_index(lock, 1);
 385                 if (reset_type == MIXED) {
 386                         int flags = quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN;
 387                         if (read_from_tree(&pathspec, oid.hash, intent_to_add))
 388                                 return 1;
 389                         if (get_git_work_tree())
 390                                 refresh_index(&the_index, flags, NULL, NULL,
 391                                               _("Unstaged changes after reset:"));
 392                 } else {
 393                         int err = reset_index(oid.hash, reset_type, quiet);
 394                         if (reset_type == KEEP && !err)
 395                                 err = reset_index(oid.hash, MIXED, quiet);
 396                         if (err)
 397                                 die(_("Could not reset index file to revision '%s'."), rev);
 398                 }
 399
 400                 if (write_locked_index(&the_index, lock, COMMIT_LOCK))
 401                         die(_("Could not write new index file."));
 402         }
 403
 404         if (!pathspec.nr && !unborn) {
 405                 /* Any resets without paths update HEAD to the head being
 406                  * switched to, saving the previous head in ORIG_HEAD before. */
 407                 update_ref_status = reset_refs(rev, oid.hash);
 408
 409                 if (reset_type == HARD && !update_ref_status && !quiet)
 410                         print_new_head_line(lookup_commit_reference(oid.hash));
 411         }
 412         if (!pathspec.nr)
 413                 remove_branch_state();
 414
 415         return update_ref_status;
 416 }