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