builtin-checkout.con commit git-rebase--interactive: auto amend only edited commit (c14c3c8)
   1#include "cache.h"
   2#include "builtin.h"
   3#include "parse-options.h"
   4#include "refs.h"
   5#include "commit.h"
   6#include "tree.h"
   7#include "tree-walk.h"
   8#include "unpack-trees.h"
   9#include "dir.h"
  10#include "run-command.h"
  11#include "merge-recursive.h"
  12#include "branch.h"
  13#include "diff.h"
  14#include "revision.h"
  15#include "remote.h"
  16
  17static const char * const checkout_usage[] = {
  18        "git checkout [options] <branch>",
  19        "git checkout [options] [<branch>] -- <file>...",
  20        NULL,
  21};
  22
  23static int post_checkout_hook(struct commit *old, struct commit *new,
  24                              int changed)
  25{
  26        struct child_process proc;
  27        const char *name = git_path("hooks/post-checkout");
  28        const char *argv[5];
  29
  30        if (access(name, X_OK) < 0)
  31                return 0;
  32
  33        memset(&proc, 0, sizeof(proc));
  34        argv[0] = name;
  35        argv[1] = xstrdup(sha1_to_hex(old->object.sha1));
  36        argv[2] = xstrdup(sha1_to_hex(new->object.sha1));
  37        argv[3] = changed ? "1" : "0";
  38        argv[4] = NULL;
  39        proc.argv = argv;
  40        proc.no_stdin = 1;
  41        proc.stdout_to_stderr = 1;
  42        return run_command(&proc);
  43}
  44
  45static int update_some(const unsigned char *sha1, const char *base, int baselen,
  46                const char *pathname, unsigned mode, int stage, void *context)
  47{
  48        int len;
  49        struct cache_entry *ce;
  50
  51        if (S_ISGITLINK(mode))
  52                return 0;
  53
  54        if (S_ISDIR(mode))
  55                return READ_TREE_RECURSIVE;
  56
  57        len = baselen + strlen(pathname);
  58        ce = xcalloc(1, cache_entry_size(len));
  59        hashcpy(ce->sha1, sha1);
  60        memcpy(ce->name, base, baselen);
  61        memcpy(ce->name + baselen, pathname, len - baselen);
  62        ce->ce_flags = create_ce_flags(len, 0);
  63        ce->ce_mode = create_ce_mode(mode);
  64        add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
  65        return 0;
  66}
  67
  68static int read_tree_some(struct tree *tree, const char **pathspec)
  69{
  70        read_tree_recursive(tree, "", 0, 0, pathspec, update_some, NULL);
  71
  72        /* update the index with the given tree's info
  73         * for all args, expanding wildcards, and exit
  74         * with any non-zero return code.
  75         */
  76        return 0;
  77}
  78
  79static int checkout_paths(struct tree *source_tree, const char **pathspec)
  80{
  81        int pos;
  82        struct checkout state;
  83        static char *ps_matched;
  84        unsigned char rev[20];
  85        int flag;
  86        struct commit *head;
  87        int errs = 0;
  88
  89        int newfd;
  90        struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
  91
  92        newfd = hold_locked_index(lock_file, 1);
  93        read_cache();
  94
  95        if (source_tree)
  96                read_tree_some(source_tree, pathspec);
  97
  98        for (pos = 0; pathspec[pos]; pos++)
  99                ;
 100        ps_matched = xcalloc(1, pos);
 101
 102        for (pos = 0; pos < active_nr; pos++) {
 103                struct cache_entry *ce = active_cache[pos];
 104                pathspec_match(pathspec, ps_matched, ce->name, 0);
 105        }
 106
 107        if (report_path_error(ps_matched, pathspec, 0))
 108                return 1;
 109
 110        /* Now we are committed to check them out */
 111        memset(&state, 0, sizeof(state));
 112        state.force = 1;
 113        state.refresh_cache = 1;
 114        for (pos = 0; pos < active_nr; pos++) {
 115                struct cache_entry *ce = active_cache[pos];
 116                if (pathspec_match(pathspec, NULL, ce->name, 0)) {
 117                        errs |= checkout_entry(ce, &state, NULL);
 118                }
 119        }
 120
 121        if (write_cache(newfd, active_cache, active_nr) ||
 122            commit_locked_index(lock_file))
 123                die("unable to write new index file");
 124
 125        resolve_ref("HEAD", rev, 0, &flag);
 126        head = lookup_commit_reference_gently(rev, 1);
 127
 128        errs |= post_checkout_hook(head, head, 0);
 129        return errs;
 130}
 131
 132static void show_local_changes(struct object *head)
 133{
 134        struct rev_info rev;
 135        /* I think we want full paths, even if we're in a subdirectory. */
 136        init_revisions(&rev, NULL);
 137        rev.abbrev = 0;
 138        rev.diffopt.output_format |= DIFF_FORMAT_NAME_STATUS;
 139        add_pending_object(&rev, head, NULL);
 140        run_diff_index(&rev, 0);
 141}
 142
 143static void describe_detached_head(char *msg, struct commit *commit)
 144{
 145        struct strbuf sb;
 146        strbuf_init(&sb, 0);
 147        parse_commit(commit);
 148        pretty_print_commit(CMIT_FMT_ONELINE, commit, &sb, 0, NULL, NULL, 0, 0);
 149        fprintf(stderr, "%s %s... %s\n", msg,
 150                find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV), sb.buf);
 151        strbuf_release(&sb);
 152}
 153
 154struct checkout_opts {
 155        int quiet;
 156        int merge;
 157        int force;
 158        int writeout_error;
 159
 160        char *new_branch;
 161        int new_branch_log;
 162        enum branch_track track;
 163};
 164
 165static int reset_tree(struct tree *tree, struct checkout_opts *o, int worktree)
 166{
 167        struct unpack_trees_options opts;
 168        struct tree_desc tree_desc;
 169
 170        memset(&opts, 0, sizeof(opts));
 171        opts.head_idx = -1;
 172        opts.update = worktree;
 173        opts.skip_unmerged = !worktree;
 174        opts.reset = 1;
 175        opts.merge = 1;
 176        opts.fn = oneway_merge;
 177        opts.verbose_update = !o->quiet;
 178        opts.src_index = &the_index;
 179        opts.dst_index = &the_index;
 180        parse_tree(tree);
 181        init_tree_desc(&tree_desc, tree->buffer, tree->size);
 182        switch (unpack_trees(1, &tree_desc, &opts)) {
 183        case -2:
 184                o->writeout_error = 1;
 185                /*
 186                 * We return 0 nevertheless, as the index is all right
 187                 * and more importantly we have made best efforts to
 188                 * update paths in the work tree, and we cannot revert
 189                 * them.
 190                 */
 191        case 0:
 192                return 0;
 193        default:
 194                return 128;
 195        }
 196}
 197
 198struct branch_info {
 199        const char *name; /* The short name used */
 200        const char *path; /* The full name of a real branch */
 201        struct commit *commit; /* The named commit */
 202};
 203
 204static void setup_branch_path(struct branch_info *branch)
 205{
 206        struct strbuf buf;
 207        strbuf_init(&buf, 0);
 208        strbuf_addstr(&buf, "refs/heads/");
 209        strbuf_addstr(&buf, branch->name);
 210        branch->path = strbuf_detach(&buf, NULL);
 211}
 212
 213static int merge_working_tree(struct checkout_opts *opts,
 214                              struct branch_info *old, struct branch_info *new)
 215{
 216        int ret;
 217        struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
 218        int newfd = hold_locked_index(lock_file, 1);
 219        read_cache();
 220
 221        if (opts->force) {
 222                ret = reset_tree(new->commit->tree, opts, 1);
 223                if (ret)
 224                        return ret;
 225        } else {
 226                struct tree_desc trees[2];
 227                struct tree *tree;
 228                struct unpack_trees_options topts;
 229
 230                memset(&topts, 0, sizeof(topts));
 231                topts.head_idx = -1;
 232                topts.src_index = &the_index;
 233                topts.dst_index = &the_index;
 234
 235                topts.msgs.not_uptodate_file = "You have local changes to '%s'; cannot switch branches.";
 236
 237                refresh_cache(REFRESH_QUIET);
 238
 239                if (unmerged_cache()) {
 240                        error("you need to resolve your current index first");
 241                        return 1;
 242                }
 243
 244                /* 2-way merge to the new branch */
 245                topts.update = 1;
 246                topts.merge = 1;
 247                topts.gently = opts->merge;
 248                topts.verbose_update = !opts->quiet;
 249                topts.fn = twoway_merge;
 250                topts.dir = xcalloc(1, sizeof(*topts.dir));
 251                topts.dir->show_ignored = 1;
 252                topts.dir->exclude_per_dir = ".gitignore";
 253                tree = parse_tree_indirect(old->commit->object.sha1);
 254                init_tree_desc(&trees[0], tree->buffer, tree->size);
 255                tree = parse_tree_indirect(new->commit->object.sha1);
 256                init_tree_desc(&trees[1], tree->buffer, tree->size);
 257
 258                ret = unpack_trees(2, trees, &topts);
 259                if (ret == -1) {
 260                        /*
 261                         * Unpack couldn't do a trivial merge; either
 262                         * give up or do a real merge, depending on
 263                         * whether the merge flag was used.
 264                         */
 265                        struct tree *result;
 266                        struct tree *work;
 267                        if (!opts->merge)
 268                                return 1;
 269                        parse_commit(old->commit);
 270
 271                        /* Do more real merge */
 272
 273                        /*
 274                         * We update the index fully, then write the
 275                         * tree from the index, then merge the new
 276                         * branch with the current tree, with the old
 277                         * branch as the base. Then we reset the index
 278                         * (but not the working tree) to the new
 279                         * branch, leaving the working tree as the
 280                         * merged version, but skipping unmerged
 281                         * entries in the index.
 282                         */
 283
 284                        add_files_to_cache(NULL, NULL, 0);
 285                        work = write_tree_from_memory();
 286
 287                        ret = reset_tree(new->commit->tree, opts, 1);
 288                        if (ret)
 289                                return ret;
 290                        merge_trees(new->commit->tree, work, old->commit->tree,
 291                                    new->name, "local", &result);
 292                        ret = reset_tree(new->commit->tree, opts, 0);
 293                        if (ret)
 294                                return ret;
 295                }
 296        }
 297
 298        if (write_cache(newfd, active_cache, active_nr) ||
 299            commit_locked_index(lock_file))
 300                die("unable to write new index file");
 301
 302        if (!opts->force)
 303                show_local_changes(&new->commit->object);
 304
 305        return 0;
 306}
 307
 308static void report_tracking(struct branch_info *new)
 309{
 310        struct strbuf sb = STRBUF_INIT;
 311        struct branch *branch = branch_get(new->name);
 312
 313        if (!format_tracking_info(branch, &sb))
 314                return;
 315        fputs(sb.buf, stdout);
 316        strbuf_release(&sb);
 317}
 318
 319static void update_refs_for_switch(struct checkout_opts *opts,
 320                                   struct branch_info *old,
 321                                   struct branch_info *new)
 322{
 323        struct strbuf msg;
 324        const char *old_desc;
 325        if (opts->new_branch) {
 326                create_branch(old->name, opts->new_branch, new->name, 0,
 327                              opts->new_branch_log, opts->track);
 328                new->name = opts->new_branch;
 329                setup_branch_path(new);
 330        }
 331
 332        strbuf_init(&msg, 0);
 333        old_desc = old->name;
 334        if (!old_desc)
 335                old_desc = sha1_to_hex(old->commit->object.sha1);
 336        strbuf_addf(&msg, "checkout: moving from %s to %s",
 337                    old_desc, new->name);
 338
 339        if (new->path) {
 340                create_symref("HEAD", new->path, msg.buf);
 341                if (!opts->quiet) {
 342                        if (old->path && !strcmp(new->path, old->path))
 343                                fprintf(stderr, "Already on \"%s\"\n",
 344                                        new->name);
 345                        else
 346                                fprintf(stderr, "Switched to%s branch \"%s\"\n",
 347                                        opts->new_branch ? " a new" : "",
 348                                        new->name);
 349                }
 350        } else if (strcmp(new->name, "HEAD")) {
 351                update_ref(msg.buf, "HEAD", new->commit->object.sha1, NULL,
 352                           REF_NODEREF, DIE_ON_ERR);
 353                if (!opts->quiet) {
 354                        if (old->path)
 355                                fprintf(stderr, "Note: moving to \"%s\" which isn't a local branch\nIf you want to create a new branch from this checkout, you may do so\n(now or later) by using -b with the checkout command again. Example:\n  git checkout -b <new_branch_name>\n", new->name);
 356                        describe_detached_head("HEAD is now at", new->commit);
 357                }
 358        }
 359        remove_branch_state();
 360        strbuf_release(&msg);
 361        if (!opts->quiet && (new->path || !strcmp(new->name, "HEAD")))
 362                report_tracking(new);
 363}
 364
 365static int switch_branches(struct checkout_opts *opts, struct branch_info *new)
 366{
 367        int ret = 0;
 368        struct branch_info old;
 369        unsigned char rev[20];
 370        int flag;
 371        memset(&old, 0, sizeof(old));
 372        old.path = resolve_ref("HEAD", rev, 0, &flag);
 373        old.commit = lookup_commit_reference_gently(rev, 1);
 374        if (!(flag & REF_ISSYMREF))
 375                old.path = NULL;
 376
 377        if (old.path && !prefixcmp(old.path, "refs/heads/"))
 378                old.name = old.path + strlen("refs/heads/");
 379
 380        if (!new->name) {
 381                new->name = "HEAD";
 382                new->commit = old.commit;
 383                if (!new->commit)
 384                        die("You are on a branch yet to be born");
 385                parse_commit(new->commit);
 386        }
 387
 388        /*
 389         * If we were on a detached HEAD, but we are now moving to
 390         * a new commit, we want to mention the old commit once more
 391         * to remind the user that it might be lost.
 392         */
 393        if (!opts->quiet && !old.path && new->commit != old.commit)
 394                describe_detached_head("Previous HEAD position was", old.commit);
 395
 396        if (!old.commit) {
 397                if (!opts->quiet) {
 398                        fprintf(stderr, "warning: You appear to be on a branch yet to be born.\n");
 399                        fprintf(stderr, "warning: Forcing checkout of %s.\n", new->name);
 400                }
 401                opts->force = 1;
 402        }
 403
 404        ret = merge_working_tree(opts, &old, new);
 405        if (ret)
 406                return ret;
 407
 408        update_refs_for_switch(opts, &old, new);
 409
 410        ret = post_checkout_hook(old.commit, new->commit, 1);
 411        return ret || opts->writeout_error;
 412}
 413
 414int cmd_checkout(int argc, const char **argv, const char *prefix)
 415{
 416        struct checkout_opts opts;
 417        unsigned char rev[20];
 418        const char *arg;
 419        struct branch_info new;
 420        struct tree *source_tree = NULL;
 421        struct option options[] = {
 422                OPT__QUIET(&opts.quiet),
 423                OPT_STRING('b', NULL, &opts.new_branch, "new branch", "branch"),
 424                OPT_BOOLEAN('l', NULL, &opts.new_branch_log, "log for new branch"),
 425                OPT_SET_INT('t', "track",  &opts.track, "track",
 426                        BRANCH_TRACK_EXPLICIT),
 427                OPT_BOOLEAN('f', NULL, &opts.force, "force"),
 428                OPT_BOOLEAN('m', NULL, &opts.merge, "merge"),
 429                OPT_END(),
 430        };
 431        int has_dash_dash;
 432
 433        memset(&opts, 0, sizeof(opts));
 434        memset(&new, 0, sizeof(new));
 435
 436        git_config(git_default_config, NULL);
 437
 438        opts.track = git_branch_track;
 439
 440        argc = parse_options(argc, argv, options, checkout_usage,
 441                             PARSE_OPT_KEEP_DASHDASH);
 442
 443        if (!opts.new_branch && (opts.track != git_branch_track))
 444                die("git checkout: --track and --no-track require -b");
 445
 446        if (opts.force && opts.merge)
 447                die("git checkout: -f and -m are incompatible");
 448
 449        /*
 450         * case 1: git checkout <ref> -- [<paths>]
 451         *
 452         *   <ref> must be a valid tree, everything after the '--' must be
 453         *   a path.
 454         *
 455         * case 2: git checkout -- [<paths>]
 456         *
 457         *   everything after the '--' must be paths.
 458         *
 459         * case 3: git checkout <something> [<paths>]
 460         *
 461         *   With no paths, if <something> is a commit, that is to
 462         *   switch to the branch or detach HEAD at it.
 463         *
 464         *   Otherwise <something> shall not be ambiguous.
 465         *   - If it's *only* a reference, treat it like case (1).
 466         *   - If it's only a path, treat it like case (2).
 467         *   - else: fail.
 468         *
 469         */
 470        if (argc) {
 471                if (!strcmp(argv[0], "--")) {       /* case (2) */
 472                        argv++;
 473                        argc--;
 474                        goto no_reference;
 475                }
 476
 477                arg = argv[0];
 478                has_dash_dash = (argc > 1) && !strcmp(argv[1], "--");
 479
 480                if (get_sha1(arg, rev)) {
 481                        if (has_dash_dash)          /* case (1) */
 482                                die("invalid reference: %s", arg);
 483                        goto no_reference;          /* case (3 -> 2) */
 484                }
 485
 486                /* we can't end up being in (2) anymore, eat the argument */
 487                argv++;
 488                argc--;
 489
 490                if ((new.commit = lookup_commit_reference_gently(rev, 1))) {
 491                        new.name = arg;
 492                        setup_branch_path(&new);
 493                        if (resolve_ref(new.path, rev, 1, NULL))
 494                                new.commit = lookup_commit_reference(rev);
 495                        else
 496                                new.path = NULL;
 497                        parse_commit(new.commit);
 498                        source_tree = new.commit->tree;
 499                } else
 500                        source_tree = parse_tree_indirect(rev);
 501
 502                if (!source_tree)                   /* case (1): want a tree */
 503                        die("reference is not a tree: %s", arg);
 504                if (!has_dash_dash) {/* case (3 -> 1) */
 505                        /*
 506                         * Do not complain the most common case
 507                         *      git checkout branch
 508                         * even if there happen to be a file called 'branch';
 509                         * it would be extremely annoying.
 510                         */
 511                        if (argc)
 512                                verify_non_filename(NULL, arg);
 513                }
 514                else {
 515                        argv++;
 516                        argc--;
 517                }
 518        }
 519
 520no_reference:
 521        if (argc) {
 522                const char **pathspec = get_pathspec(prefix, argv);
 523
 524                if (!pathspec)
 525                        die("invalid path specification");
 526
 527                /* Checkout paths */
 528                if (opts.new_branch || opts.force || opts.merge) {
 529                        if (argc == 1) {
 530                                die("git checkout: updating paths is incompatible with switching branches/forcing\nDid you intend to checkout '%s' which can not be resolved as commit?", argv[0]);
 531                        } else {
 532                                die("git checkout: updating paths is incompatible with switching branches/forcing");
 533                        }
 534                }
 535
 536                return checkout_paths(source_tree, pathspec);
 537        }
 538
 539        if (new.name && !new.commit) {
 540                die("Cannot switch branch to a non-commit.");
 541        }
 542
 543        return switch_branches(&opts, &new);
 544}