git.oblomov.eu Git - git/blob - builtin/rebase.c

   1 /*
   2  * "git rebase" builtin command
   3  *
   4  * Copyright (c) 2018 Pratik Karki
   5  */
   6
   7 #include "builtin.h"
   8 #include "run-command.h"
   9 #include "exec-cmd.h"
  10 #include "argv-array.h"
  11 #include "dir.h"
  12 #include "packfile.h"
  13 #include "refs.h"
  14 #include "quote.h"
  15 #include "config.h"
  16 #include "cache-tree.h"
  17 #include "unpack-trees.h"
  18 #include "lockfile.h"
  19 #include "parse-options.h"
  20 #include "commit.h"
  21 #include "diff.h"
  22 #include "wt-status.h"
  23 #include "revision.h"
  24 #include "rerere.h"
  25
  26 static char const * const builtin_rebase_usage[] = {
  27         N_("git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] "
  28                 "[<upstream>] [<branch>]"),
  29         N_("git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] "
  30                 "--root [<branch>]"),
  31         N_("git rebase --continue | --abort | --skip | --edit-todo"),
  32         NULL
  33 };
  34
  35 static GIT_PATH_FUNC(apply_dir, "rebase-apply")
  36 static GIT_PATH_FUNC(merge_dir, "rebase-merge")
  37
  38 enum rebase_type {
  39         REBASE_UNSPECIFIED = -1,
  40         REBASE_AM,
  41         REBASE_MERGE,
  42         REBASE_INTERACTIVE,
  43         REBASE_PRESERVE_MERGES
  44 };
  45
  46 static int use_builtin_rebase(void)
  47 {
  48         struct child_process cp = CHILD_PROCESS_INIT;
  49         struct strbuf out = STRBUF_INIT;
  50         int ret;
  51
  52         argv_array_pushl(&cp.args,
  53                          "config", "--bool", "rebase.usebuiltin", NULL);
  54         cp.git_cmd = 1;
  55         if (capture_command(&cp, &out, 6)) {
  56                 strbuf_release(&out);
  57                 return 0;
  58         }
  59
  60         strbuf_trim(&out);
  61         ret = !strcmp("true", out.buf);
  62         strbuf_release(&out);
  63         return ret;
  64 }
  65
  66 struct rebase_options {
  67         enum rebase_type type;
  68         const char *state_dir;
  69         struct commit *upstream;
  70         const char *upstream_name;
  71         const char *upstream_arg;
  72         char *head_name;
  73         struct object_id orig_head;
  74         struct commit *onto;
  75         const char *onto_name;
  76         const char *revisions;
  77         const char *switch_to;
  78         int root;
  79         struct commit *restrict_revision;
  80         int dont_finish_rebase;
  81         enum {
  82                 REBASE_NO_QUIET = 1<<0,
  83                 REBASE_VERBOSE = 1<<1,
  84                 REBASE_DIFFSTAT = 1<<2,
  85                 REBASE_FORCE = 1<<3,
  86                 REBASE_INTERACTIVE_EXPLICIT = 1<<4,
  87         } flags;
  88         struct strbuf git_am_opt;
  89         const char *action;
  90         int signoff;
  91         int allow_rerere_autoupdate;
  92         int keep_empty;
  93         int autosquash;
  94         char *gpg_sign_opt;
  95         int autostash;
  96 };
  97
  98 static int is_interactive(struct rebase_options *opts)
  99 {
 100         return opts->type == REBASE_INTERACTIVE ||
 101                 opts->type == REBASE_PRESERVE_MERGES;
 102 }
 103
 104 static void imply_interactive(struct rebase_options *opts, const char *option)
 105 {
 106         switch (opts->type) {
 107         case REBASE_AM:
 108                 die(_("%s requires an interactive rebase"), option);
 109                 break;
 110         case REBASE_INTERACTIVE:
 111         case REBASE_PRESERVE_MERGES:
 112                 break;
 113         case REBASE_MERGE:
 114                 /* we silently *upgrade* --merge to --interactive if needed */
 115         default:
 116                 opts->type = REBASE_INTERACTIVE; /* implied */
 117                 break;
 118         }
 119 }
 120
 121 /* Returns the filename prefixed by the state_dir */
 122 static const char *state_dir_path(const char *filename, struct rebase_options *opts)
 123 {
 124         static struct strbuf path = STRBUF_INIT;
 125         static size_t prefix_len;
 126
 127         if (!prefix_len) {
 128                 strbuf_addf(&path, "%s/", opts->state_dir);
 129                 prefix_len = path.len;
 130         }
 131
 132         strbuf_setlen(&path, prefix_len);
 133         strbuf_addstr(&path, filename);
 134         return path.buf;
 135 }
 136
 137 /* Read one file, then strip line endings */
 138 static int read_one(const char *path, struct strbuf *buf)
 139 {
 140         if (strbuf_read_file(buf, path, 0) < 0)
 141                 return error_errno(_("could not read '%s'"), path);
 142         strbuf_trim_trailing_newline(buf);
 143         return 0;
 144 }
 145
 146 /* Initialize the rebase options from the state directory. */
 147 static int read_basic_state(struct rebase_options *opts)
 148 {
 149         struct strbuf head_name = STRBUF_INIT;
 150         struct strbuf buf = STRBUF_INIT;
 151         struct object_id oid;
 152
 153         if (read_one(state_dir_path("head-name", opts), &head_name) ||
 154             read_one(state_dir_path("onto", opts), &buf))
 155                 return -1;
 156         opts->head_name = starts_with(head_name.buf, "refs/") ?
 157                 xstrdup(head_name.buf) : NULL;
 158         strbuf_release(&head_name);
 159         if (get_oid(buf.buf, &oid))
 160                 return error(_("could not get 'onto': '%s'"), buf.buf);
 161         opts->onto = lookup_commit_or_die(&oid, buf.buf);
 162
 163         /*
 164          * We always write to orig-head, but interactive rebase used to write to
 165          * head. Fall back to reading from head to cover for the case that the
 166          * user upgraded git with an ongoing interactive rebase.
 167          */
 168         strbuf_reset(&buf);
 169         if (file_exists(state_dir_path("orig-head", opts))) {
 170                 if (read_one(state_dir_path("orig-head", opts), &buf))
 171                         return -1;
 172         } else if (read_one(state_dir_path("head", opts), &buf))
 173                 return -1;
 174         if (get_oid(buf.buf, &opts->orig_head))
 175                 return error(_("invalid orig-head: '%s'"), buf.buf);
 176
 177         strbuf_reset(&buf);
 178         if (read_one(state_dir_path("quiet", opts), &buf))
 179                 return -1;
 180         if (buf.len)
 181                 opts->flags &= ~REBASE_NO_QUIET;
 182         else
 183                 opts->flags |= REBASE_NO_QUIET;
 184
 185         if (file_exists(state_dir_path("verbose", opts)))
 186                 opts->flags |= REBASE_VERBOSE;
 187
 188         if (file_exists(state_dir_path("signoff", opts))) {
 189                 opts->signoff = 1;
 190                 opts->flags |= REBASE_FORCE;
 191         }
 192
 193         if (file_exists(state_dir_path("allow_rerere_autoupdate", opts))) {
 194                 strbuf_reset(&buf);
 195                 if (read_one(state_dir_path("allow_rerere_autoupdate", opts),
 196                             &buf))
 197                         return -1;
 198                 if (!strcmp(buf.buf, "--rerere-autoupdate"))
 199                         opts->allow_rerere_autoupdate = 1;
 200                 else if (!strcmp(buf.buf, "--no-rerere-autoupdate"))
 201                         opts->allow_rerere_autoupdate = 0;
 202                 else
 203                         warning(_("ignoring invalid allow_rerere_autoupdate: "
 204                                   "'%s'"), buf.buf);
 205         } else
 206                 opts->allow_rerere_autoupdate = -1;
 207
 208         if (file_exists(state_dir_path("gpg_sign_opt", opts))) {
 209                 strbuf_reset(&buf);
 210                 if (read_one(state_dir_path("gpg_sign_opt", opts),
 211                             &buf))
 212                         return -1;
 213                 free(opts->gpg_sign_opt);
 214                 opts->gpg_sign_opt = xstrdup(buf.buf);
 215         }
 216
 217         strbuf_release(&buf);
 218
 219         return 0;
 220 }
 221
 222 static int apply_autostash(struct rebase_options *opts)
 223 {
 224         const char *path = state_dir_path("autostash", opts);
 225         struct strbuf autostash = STRBUF_INIT;
 226         struct child_process stash_apply = CHILD_PROCESS_INIT;
 227
 228         if (!file_exists(path))
 229                 return 0;
 230
 231         if (read_one(state_dir_path("autostash", opts), &autostash))
 232                 return error(_("Could not read '%s'"), path);
 233         argv_array_pushl(&stash_apply.args,
 234                          "stash", "apply", autostash.buf, NULL);
 235         stash_apply.git_cmd = 1;
 236         stash_apply.no_stderr = stash_apply.no_stdout =
 237                 stash_apply.no_stdin = 1;
 238         if (!run_command(&stash_apply))
 239                 printf(_("Applied autostash.\n"));
 240         else {
 241                 struct argv_array args = ARGV_ARRAY_INIT;
 242                 int res = 0;
 243
 244                 argv_array_pushl(&args,
 245                                  "stash", "store", "-m", "autostash", "-q",
 246                                  autostash.buf, NULL);
 247                 if (run_command_v_opt(args.argv, RUN_GIT_CMD))
 248                         res = error(_("Cannot store %s"), autostash.buf);
 249                 argv_array_clear(&args);
 250                 strbuf_release(&autostash);
 251                 if (res)
 252                         return res;
 253
 254                 fprintf(stderr,
 255                         _("Applying autostash resulted in conflicts.\n"
 256                           "Your changes are safe in the stash.\n"
 257                           "You can run \"git stash pop\" or \"git stash drop\" "
 258                           "at any time.\n"));
 259         }
 260
 261         strbuf_release(&autostash);
 262         return 0;
 263 }
 264
 265 static int finish_rebase(struct rebase_options *opts)
 266 {
 267         struct strbuf dir = STRBUF_INIT;
 268         const char *argv_gc_auto[] = { "gc", "--auto", NULL };
 269
 270         delete_ref(NULL, "REBASE_HEAD", NULL, REF_NO_DEREF);
 271         apply_autostash(opts);
 272         close_all_packs(the_repository->objects);
 273         /*
 274          * We ignore errors in 'gc --auto', since the
 275          * user should see them.
 276          */
 277         run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
 278         strbuf_addstr(&dir, opts->state_dir);
 279         remove_dir_recursively(&dir, 0);
 280         strbuf_release(&dir);
 281
 282         return 0;
 283 }
 284
 285 static struct commit *peel_committish(const char *name)
 286 {
 287         struct object *obj;
 288         struct object_id oid;
 289
 290         if (get_oid(name, &oid))
 291                 return NULL;
 292         obj = parse_object(the_repository, &oid);
 293         return (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
 294 }
 295
 296 static void add_var(struct strbuf *buf, const char *name, const char *value)
 297 {
 298         if (!value)
 299                 strbuf_addf(buf, "unset %s; ", name);
 300         else {
 301                 strbuf_addf(buf, "%s=", name);
 302                 sq_quote_buf(buf, value);
 303                 strbuf_addstr(buf, "; ");
 304         }
 305 }
 306
 307 static int run_specific_rebase(struct rebase_options *opts)
 308 {
 309         const char *argv[] = { NULL, NULL };
 310         struct strbuf script_snippet = STRBUF_INIT;
 311         int status;
 312         const char *backend, *backend_func;
 313
 314         add_var(&script_snippet, "GIT_DIR", absolute_path(get_git_dir()));
 315         add_var(&script_snippet, "state_dir", opts->state_dir);
 316
 317         add_var(&script_snippet, "upstream_name", opts->upstream_name);
 318         add_var(&script_snippet, "upstream", opts->upstream ?
 319                 oid_to_hex(&opts->upstream->object.oid) : NULL);
 320         add_var(&script_snippet, "head_name",
 321                 opts->head_name ? opts->head_name : "detached HEAD");
 322         add_var(&script_snippet, "orig_head", oid_to_hex(&opts->orig_head));
 323         add_var(&script_snippet, "onto", opts->onto ?
 324                 oid_to_hex(&opts->onto->object.oid) : NULL);
 325         add_var(&script_snippet, "onto_name", opts->onto_name);
 326         add_var(&script_snippet, "revisions", opts->revisions);
 327         add_var(&script_snippet, "restrict_revision", opts->restrict_revision ?
 328                 oid_to_hex(&opts->restrict_revision->object.oid) : NULL);
 329         add_var(&script_snippet, "GIT_QUIET",
 330                 opts->flags & REBASE_NO_QUIET ? "" : "t");
 331         add_var(&script_snippet, "git_am_opt", opts->git_am_opt.buf);
 332         add_var(&script_snippet, "verbose",
 333                 opts->flags & REBASE_VERBOSE ? "t" : "");
 334         add_var(&script_snippet, "diffstat",
 335                 opts->flags & REBASE_DIFFSTAT ? "t" : "");
 336         add_var(&script_snippet, "force_rebase",
 337                 opts->flags & REBASE_FORCE ? "t" : "");
 338         if (opts->switch_to)
 339                 add_var(&script_snippet, "switch_to", opts->switch_to);
 340         add_var(&script_snippet, "action", opts->action ? opts->action : "");
 341         add_var(&script_snippet, "signoff", opts->signoff ? "--signoff" : "");
 342         add_var(&script_snippet, "allow_rerere_autoupdate",
 343                 opts->allow_rerere_autoupdate < 0 ? "" :
 344                 opts->allow_rerere_autoupdate ?
 345                 "--rerere-autoupdate" : "--no-rerere-autoupdate");
 346         add_var(&script_snippet, "keep_empty", opts->keep_empty ? "yes" : "");
 347         add_var(&script_snippet, "autosquash", opts->autosquash ? "t" : "");
 348         add_var(&script_snippet, "gpg_sign_opt", opts->gpg_sign_opt);
 349
 350         switch (opts->type) {
 351         case REBASE_AM:
 352                 backend = "git-rebase--am";
 353                 backend_func = "git_rebase__am";
 354                 break;
 355         case REBASE_INTERACTIVE:
 356                 backend = "git-rebase--interactive";
 357                 backend_func = "git_rebase__interactive";
 358                 break;
 359         case REBASE_MERGE:
 360                 backend = "git-rebase--merge";
 361                 backend_func = "git_rebase__merge";
 362                 break;
 363         case REBASE_PRESERVE_MERGES:
 364                 backend = "git-rebase--preserve-merges";
 365                 backend_func = "git_rebase__preserve_merges";
 366                 break;
 367         default:
 368                 BUG("Unhandled rebase type %d", opts->type);
 369                 break;
 370         }
 371
 372         strbuf_addf(&script_snippet,
 373                     ". git-sh-setup && . git-rebase--common &&"
 374                     " . %s && %s", backend, backend_func);
 375         argv[0] = script_snippet.buf;
 376
 377         status = run_command_v_opt(argv, RUN_USING_SHELL);
 378         if (opts->dont_finish_rebase)
 379                 ; /* do nothing */
 380         else if (status == 0) {
 381                 if (!file_exists(state_dir_path("stopped-sha", opts)))
 382                         finish_rebase(opts);
 383         } else if (status == 2) {
 384                 struct strbuf dir = STRBUF_INIT;
 385
 386                 apply_autostash(opts);
 387                 strbuf_addstr(&dir, opts->state_dir);
 388                 remove_dir_recursively(&dir, 0);
 389                 strbuf_release(&dir);
 390                 die("Nothing to do");
 391         }
 392
 393         strbuf_release(&script_snippet);
 394
 395         return status ? -1 : 0;
 396 }
 397
 398 #define GIT_REFLOG_ACTION_ENVIRONMENT "GIT_REFLOG_ACTION"
 399
 400 static int reset_head(struct object_id *oid, const char *action,
 401                       const char *switch_to_branch, int detach_head)
 402 {
 403         struct object_id head_oid;
 404         struct tree_desc desc;
 405         struct lock_file lock = LOCK_INIT;
 406         struct unpack_trees_options unpack_tree_opts;
 407         struct tree *tree;
 408         const char *reflog_action;
 409         struct strbuf msg = STRBUF_INIT;
 410         size_t prefix_len;
 411         struct object_id *orig = NULL, oid_orig,
 412                 *old_orig = NULL, oid_old_orig;
 413         int ret = 0;
 414
 415         if (switch_to_branch && !starts_with(switch_to_branch, "refs/"))
 416                 BUG("Not a fully qualified branch: '%s'", switch_to_branch);
 417
 418         if (hold_locked_index(&lock, LOCK_REPORT_ON_ERROR) < 0)
 419                 return -1;
 420
 421         if (!oid) {
 422                 if (get_oid("HEAD", &head_oid)) {
 423                         rollback_lock_file(&lock);
 424                         return error(_("could not determine HEAD revision"));
 425                 }
 426                 oid = &head_oid;
 427         }
 428
 429         memset(&unpack_tree_opts, 0, sizeof(unpack_tree_opts));
 430         setup_unpack_trees_porcelain(&unpack_tree_opts, action);
 431         unpack_tree_opts.head_idx = 1;
 432         unpack_tree_opts.src_index = the_repository->index;
 433         unpack_tree_opts.dst_index = the_repository->index;
 434         unpack_tree_opts.fn = oneway_merge;
 435         unpack_tree_opts.update = 1;
 436         unpack_tree_opts.merge = 1;
 437         if (!detach_head)
 438                 unpack_tree_opts.reset = 1;
 439
 440         if (read_index_unmerged(the_repository->index) < 0) {
 441                 rollback_lock_file(&lock);
 442                 return error(_("could not read index"));
 443         }
 444
 445         if (!fill_tree_descriptor(&desc, oid)) {
 446                 error(_("failed to find tree of %s"), oid_to_hex(oid));
 447                 rollback_lock_file(&lock);
 448                 free((void *)desc.buffer);
 449                 return -1;
 450         }
 451
 452         if (unpack_trees(1, &desc, &unpack_tree_opts)) {
 453                 rollback_lock_file(&lock);
 454                 free((void *)desc.buffer);
 455                 return -1;
 456         }
 457
 458         tree = parse_tree_indirect(oid);
 459         prime_cache_tree(the_repository->index, tree);
 460
 461         if (write_locked_index(the_repository->index, &lock, COMMIT_LOCK) < 0)
 462                 ret = error(_("could not write index"));
 463         free((void *)desc.buffer);
 464
 465         if (ret)
 466                 return ret;
 467
 468         reflog_action = getenv(GIT_REFLOG_ACTION_ENVIRONMENT);
 469         strbuf_addf(&msg, "%s: ", reflog_action ? reflog_action : "rebase");
 470         prefix_len = msg.len;
 471
 472         if (!get_oid("ORIG_HEAD", &oid_old_orig))
 473                 old_orig = &oid_old_orig;
 474         if (!get_oid("HEAD", &oid_orig)) {
 475                 orig = &oid_orig;
 476                 strbuf_addstr(&msg, "updating ORIG_HEAD");
 477                 update_ref(msg.buf, "ORIG_HEAD", orig, old_orig, 0,
 478                            UPDATE_REFS_MSG_ON_ERR);
 479         } else if (old_orig)
 480                 delete_ref(NULL, "ORIG_HEAD", old_orig, 0);
 481         strbuf_setlen(&msg, prefix_len);
 482         strbuf_addstr(&msg, "updating HEAD");
 483         if (!switch_to_branch)
 484                 ret = update_ref(msg.buf, "HEAD", oid, orig, REF_NO_DEREF,
 485                                  UPDATE_REFS_MSG_ON_ERR);
 486         else {
 487                 ret = create_symref("HEAD", switch_to_branch, msg.buf);
 488                 if (!ret)
 489                         ret = update_ref(msg.buf, "HEAD", oid, NULL, 0,
 490                                          UPDATE_REFS_MSG_ON_ERR);
 491         }
 492
 493         strbuf_release(&msg);
 494         return ret;
 495 }
 496
 497 static int rebase_config(const char *var, const char *value, void *data)
 498 {
 499         struct rebase_options *opts = data;
 500
 501         if (!strcmp(var, "rebase.stat")) {
 502                 if (git_config_bool(var, value))
 503                         opts->flags |= REBASE_DIFFSTAT;
 504                 else
 505                         opts->flags &= !REBASE_DIFFSTAT;
 506                 return 0;
 507         }
 508
 509         if (!strcmp(var, "rebase.autosquash")) {
 510                 opts->autosquash = git_config_bool(var, value);
 511                 return 0;
 512         }
 513
 514         if (!strcmp(var, "commit.gpgsign")) {
 515                 free(opts->gpg_sign_opt);
 516                 opts->gpg_sign_opt = git_config_bool(var, value) ?
 517                         xstrdup("-S") : NULL;
 518                 return 0;
 519         }
 520
 521         if (!strcmp(var, "rebase.autostash")) {
 522                 opts->autostash = git_config_bool(var, value);
 523                 return 0;
 524         }
 525
 526         return git_default_config(var, value, data);
 527 }
 528
 529 /*
 530  * Determines whether the commits in from..to are linear, i.e. contain
 531  * no merge commits. This function *expects* `from` to be an ancestor of
 532  * `to`.
 533  */
 534 static int is_linear_history(struct commit *from, struct commit *to)
 535 {
 536         while (to && to != from) {
 537                 parse_commit(to);
 538                 if (!to->parents)
 539                         return 1;
 540                 if (to->parents->next)
 541                         return 0;
 542                 to = to->parents->item;
 543         }
 544         return 1;
 545 }
 546
 547 static int can_fast_forward(struct commit *onto, struct object_id *head_oid,
 548                             struct object_id *merge_base)
 549 {
 550         struct commit *head = lookup_commit(the_repository, head_oid);
 551         struct commit_list *merge_bases;
 552         int res;
 553
 554         if (!head)
 555                 return 0;
 556
 557         merge_bases = get_merge_bases(onto, head);
 558         if (merge_bases && !merge_bases->next) {
 559                 oidcpy(merge_base, &merge_bases->item->object.oid);
 560                 res = !oidcmp(merge_base, &onto->object.oid);
 561         } else {
 562                 oidcpy(merge_base, &null_oid);
 563                 res = 0;
 564         }
 565         free_commit_list(merge_bases);
 566         return res && is_linear_history(onto, head);
 567 }
 568
 569 /* -i followed by -m is still -i */
 570 static int parse_opt_merge(const struct option *opt, const char *arg, int unset)
 571 {
 572         struct rebase_options *opts = opt->value;
 573
 574         if (!is_interactive(opts))
 575                 opts->type = REBASE_MERGE;
 576
 577         return 0;
 578 }
 579
 580 /* -i followed by -p is still explicitly interactive, but -p alone is not */
 581 static int parse_opt_interactive(const struct option *opt, const char *arg,
 582                                  int unset)
 583 {
 584         struct rebase_options *opts = opt->value;
 585
 586         opts->type = REBASE_INTERACTIVE;
 587         opts->flags |= REBASE_INTERACTIVE_EXPLICIT;
 588
 589         return 0;
 590 }
 591
 592 int cmd_rebase(int argc, const char **argv, const char *prefix)
 593 {
 594         struct rebase_options options = {
 595                 .type = REBASE_UNSPECIFIED,
 596                 .flags = REBASE_NO_QUIET,
 597                 .git_am_opt = STRBUF_INIT,
 598                 .allow_rerere_autoupdate  = -1,
 599         };
 600         const char *branch_name;
 601         int ret, flags, total_argc, in_progress = 0;
 602         int ok_to_skip_pre_rebase = 0;
 603         struct strbuf msg = STRBUF_INIT;
 604         struct strbuf revisions = STRBUF_INIT;
 605         struct strbuf buf = STRBUF_INIT;
 606         struct object_id merge_base;
 607         enum {
 608                 NO_ACTION,
 609                 ACTION_CONTINUE,
 610                 ACTION_SKIP,
 611                 ACTION_ABORT,
 612                 ACTION_QUIT,
 613                 ACTION_EDIT_TODO,
 614                 ACTION_SHOW_CURRENT_PATCH,
 615         } action = NO_ACTION;
 616         int committer_date_is_author_date = 0;
 617         int ignore_date = 0;
 618         int ignore_whitespace = 0;
 619         const char *gpg_sign = NULL;
 620         int opt_c = -1;
 621         struct string_list whitespace = STRING_LIST_INIT_NODUP;
 622         struct option builtin_rebase_options[] = {
 623                 OPT_STRING(0, "onto", &options.onto_name,
 624                            N_("revision"),
 625                            N_("rebase onto given branch instead of upstream")),
 626                 OPT_BOOL(0, "no-verify", &ok_to_skip_pre_rebase,
 627                          N_("allow pre-rebase hook to run")),
 628                 OPT_NEGBIT('q', "quiet", &options.flags,
 629                            N_("be quiet. implies --no-stat"),
 630                            REBASE_NO_QUIET| REBASE_VERBOSE | REBASE_DIFFSTAT),
 631                 OPT_BIT('v', "verbose", &options.flags,
 632                         N_("display a diffstat of what changed upstream"),
 633                         REBASE_NO_QUIET | REBASE_VERBOSE | REBASE_DIFFSTAT),
 634                 {OPTION_NEGBIT, 'n', "no-stat", &options.flags, NULL,
 635                         N_("do not show diffstat of what changed upstream"),
 636                         PARSE_OPT_NOARG, NULL, REBASE_DIFFSTAT },
 637                 OPT_BOOL(0, "ignore-whitespace", &ignore_whitespace,
 638                          N_("passed to 'git apply'")),
 639                 OPT_BOOL(0, "signoff", &options.signoff,
 640                          N_("add a Signed-off-by: line to each commit")),
 641                 OPT_BOOL(0, "committer-date-is-author-date",
 642                          &committer_date_is_author_date,
 643                          N_("passed to 'git am'")),
 644                 OPT_BOOL(0, "ignore-date", &ignore_date,
 645                          N_("passed to 'git am'")),
 646                 OPT_BIT('f', "force-rebase", &options.flags,
 647                         N_("cherry-pick all commits, even if unchanged"),
 648                         REBASE_FORCE),
 649                 OPT_BIT(0, "no-ff", &options.flags,
 650                         N_("cherry-pick all commits, even if unchanged"),
 651                         REBASE_FORCE),
 652                 OPT_CMDMODE(0, "continue", &action, N_("continue"),
 653                             ACTION_CONTINUE),
 654                 OPT_CMDMODE(0, "skip", &action,
 655                             N_("skip current patch and continue"), ACTION_SKIP),
 656                 OPT_CMDMODE(0, "abort", &action,
 657                             N_("abort and check out the original branch"),
 658                             ACTION_ABORT),
 659                 OPT_CMDMODE(0, "quit", &action,
 660                             N_("abort but keep HEAD where it is"), ACTION_QUIT),
 661                 OPT_CMDMODE(0, "edit-todo", &action, N_("edit the todo list "
 662                             "during an interactive rebase"), ACTION_EDIT_TODO),
 663                 OPT_CMDMODE(0, "show-current-patch", &action,
 664                             N_("show the patch file being applied or merged"),
 665                             ACTION_SHOW_CURRENT_PATCH),
 666                 { OPTION_CALLBACK, 'm', "merge", &options, NULL,
 667                         N_("use merging strategies to rebase"),
 668                         PARSE_OPT_NOARG | PARSE_OPT_NONEG,
 669                         parse_opt_merge },
 670                 { OPTION_CALLBACK, 'i', "interactive", &options, NULL,
 671                         N_("let the user edit the list of commits to rebase"),
 672                         PARSE_OPT_NOARG | PARSE_OPT_NONEG,
 673                         parse_opt_interactive },
 674                 OPT_SET_INT('p', "preserve-merges", &options.type,
 675                             N_("try to recreate merges instead of ignoring "
 676                                "them"), REBASE_PRESERVE_MERGES),
 677                 OPT_BOOL(0, "rerere-autoupdate",
 678                          &options.allow_rerere_autoupdate,
 679                          N_("allow rerere to update index  with resolved "
 680                             "conflict")),
 681                 OPT_BOOL('k', "keep-empty", &options.keep_empty,
 682                          N_("preserve empty commits during rebase")),
 683                 OPT_BOOL(0, "autosquash", &options.autosquash,
 684                          N_("move commits that begin with "
 685                             "squash!/fixup! under -i")),
 686                 { OPTION_STRING, 'S', "gpg-sign", &gpg_sign, N_("key-id"),
 687                         N_("GPG-sign commits"),
 688                         PARSE_OPT_OPTARG, NULL, (intptr_t) "" },
 689                 OPT_STRING_LIST(0, "whitespace", &whitespace,
 690                                 N_("whitespace"), N_("passed to 'git apply'")),
 691                 OPT_SET_INT('C', NULL, &opt_c, N_("passed to 'git apply'"),
 692                             REBASE_AM),
 693                 OPT_BOOL(0, "autostash", &options.autostash,
 694                          N_("automatically stash/stash pop before and after")),
 695                 OPT_END(),
 696         };
 697
 698         /*
 699          * NEEDSWORK: Once the builtin rebase has been tested enough
 700          * and git-legacy-rebase.sh is retired to contrib/, this preamble
 701          * can be removed.
 702          */
 703
 704         if (!use_builtin_rebase()) {
 705                 const char *path = mkpath("%s/git-legacy-rebase",
 706                                           git_exec_path());
 707
 708                 if (sane_execvp(path, (char **)argv) < 0)
 709                         die_errno(_("could not exec %s"), path);
 710                 else
 711                         BUG("sane_execvp() returned???");
 712         }
 713
 714         if (argc == 2 && !strcmp(argv[1], "-h"))
 715                 usage_with_options(builtin_rebase_usage,
 716                                    builtin_rebase_options);
 717
 718         prefix = setup_git_directory();
 719         trace_repo_setup(prefix);
 720         setup_work_tree();
 721
 722         git_config(rebase_config, &options);
 723
 724         strbuf_reset(&buf);
 725         strbuf_addf(&buf, "%s/applying", apply_dir());
 726         if(file_exists(buf.buf))
 727                 die(_("It looks like 'git am' is in progress. Cannot rebase."));
 728
 729         if (is_directory(apply_dir())) {
 730                 options.type = REBASE_AM;
 731                 options.state_dir = apply_dir();
 732         } else if (is_directory(merge_dir())) {
 733                 strbuf_reset(&buf);
 734                 strbuf_addf(&buf, "%s/rewritten", merge_dir());
 735                 if (is_directory(buf.buf)) {
 736                         options.type = REBASE_PRESERVE_MERGES;
 737                         options.flags |= REBASE_INTERACTIVE_EXPLICIT;
 738                 } else {
 739                         strbuf_reset(&buf);
 740                         strbuf_addf(&buf, "%s/interactive", merge_dir());
 741                         if(file_exists(buf.buf)) {
 742                                 options.type = REBASE_INTERACTIVE;
 743                                 options.flags |= REBASE_INTERACTIVE_EXPLICIT;
 744                         } else
 745                                 options.type = REBASE_MERGE;
 746                 }
 747                 options.state_dir = merge_dir();
 748         }
 749
 750         if (options.type != REBASE_UNSPECIFIED)
 751                 in_progress = 1;
 752
 753         total_argc = argc;
 754         argc = parse_options(argc, argv, prefix,
 755                              builtin_rebase_options,
 756                              builtin_rebase_usage, 0);
 757
 758         if (action != NO_ACTION && total_argc != 2) {
 759                 usage_with_options(builtin_rebase_usage,
 760                                    builtin_rebase_options);
 761         }
 762
 763         if (argc > 2)
 764                 usage_with_options(builtin_rebase_usage,
 765                                    builtin_rebase_options);
 766
 767         if (action != NO_ACTION && !in_progress)
 768                 die(_("No rebase in progress?"));
 769
 770         if (action == ACTION_EDIT_TODO && !is_interactive(&options))
 771                 die(_("The --edit-todo action can only be used during "
 772                       "interactive rebase."));
 773
 774         switch (action) {
 775         case ACTION_CONTINUE: {
 776                 struct object_id head;
 777                 struct lock_file lock_file = LOCK_INIT;
 778                 int fd;
 779
 780                 options.action = "continue";
 781
 782                 /* Sanity check */
 783                 if (get_oid("HEAD", &head))
 784                         die(_("Cannot read HEAD"));
 785
 786                 fd = hold_locked_index(&lock_file, 0);
 787                 if (read_index(the_repository->index) < 0)
 788                         die(_("could not read index"));
 789                 refresh_index(the_repository->index, REFRESH_QUIET, NULL, NULL,
 790                               NULL);
 791                 if (0 <= fd)
 792                         update_index_if_able(the_repository->index,
 793                                              &lock_file);
 794                 rollback_lock_file(&lock_file);
 795
 796                 if (has_unstaged_changes(1)) {
 797                         puts(_("You must edit all merge conflicts and then\n"
 798                                "mark them as resolved using git add"));
 799                         exit(1);
 800                 }
 801                 if (read_basic_state(&options))
 802                         exit(1);
 803                 goto run_rebase;
 804         }
 805         case ACTION_SKIP: {
 806                 struct string_list merge_rr = STRING_LIST_INIT_DUP;
 807
 808                 options.action = "skip";
 809
 810                 rerere_clear(&merge_rr);
 811                 string_list_clear(&merge_rr, 1);
 812
 813                 if (reset_head(NULL, "reset", NULL, 0) < 0)
 814                         die(_("could not discard worktree changes"));
 815                 if (read_basic_state(&options))
 816                         exit(1);
 817                 goto run_rebase;
 818         }
 819         case ACTION_ABORT: {
 820                 struct string_list merge_rr = STRING_LIST_INIT_DUP;
 821                 options.action = "abort";
 822
 823                 rerere_clear(&merge_rr);
 824                 string_list_clear(&merge_rr, 1);
 825
 826                 if (read_basic_state(&options))
 827                         exit(1);
 828                 if (reset_head(&options.orig_head, "reset",
 829                                options.head_name, 0) < 0)
 830                         die(_("could not move back to %s"),
 831                             oid_to_hex(&options.orig_head));
 832                 ret = finish_rebase(&options);
 833                 goto cleanup;
 834         }
 835         case ACTION_QUIT: {
 836                 strbuf_reset(&buf);
 837                 strbuf_addstr(&buf, options.state_dir);
 838                 ret = !!remove_dir_recursively(&buf, 0);
 839                 if (ret)
 840                         die(_("could not remove '%s'"), options.state_dir);
 841                 goto cleanup;
 842         }
 843         case ACTION_EDIT_TODO:
 844                 options.action = "edit-todo";
 845                 options.dont_finish_rebase = 1;
 846                 goto run_rebase;
 847         case ACTION_SHOW_CURRENT_PATCH:
 848                 options.action = "show-current-patch";
 849                 options.dont_finish_rebase = 1;
 850                 goto run_rebase;
 851         case NO_ACTION:
 852                 break;
 853         default:
 854                 BUG("action: %d", action);
 855         }
 856
 857         /* Make sure no rebase is in progress */
 858         if (in_progress) {
 859                 const char *last_slash = strrchr(options.state_dir, '/');
 860                 const char *state_dir_base =
 861                         last_slash ? last_slash + 1 : options.state_dir;
 862                 const char *cmd_live_rebase =
 863                         "git rebase (--continue | --abort | --skip)";
 864                 strbuf_reset(&buf);
 865                 strbuf_addf(&buf, "rm -fr \"%s\"", options.state_dir);
 866                 die(_("It seems that there is already a %s directory, and\n"
 867                       "I wonder if you are in the middle of another rebase.  "
 868                       "If that is the\n"
 869                       "case, please try\n\t%s\n"
 870                       "If that is not the case, please\n\t%s\n"
 871                       "and run me again.  I am stopping in case you still "
 872                       "have something\n"
 873                       "valuable there.\n"),
 874                     state_dir_base, cmd_live_rebase, buf.buf);
 875         }
 876
 877         if (!(options.flags & REBASE_NO_QUIET))
 878                 strbuf_addstr(&options.git_am_opt, " -q");
 879
 880         if (committer_date_is_author_date) {
 881                 strbuf_addstr(&options.git_am_opt,
 882                               " --committer-date-is-author-date");
 883                 options.flags |= REBASE_FORCE;
 884         }
 885
 886         if (ignore_whitespace)
 887                 strbuf_addstr(&options.git_am_opt, " --ignore-whitespace");
 888
 889         if (ignore_date) {
 890                 strbuf_addstr(&options.git_am_opt, " --ignore-date");
 891                 options.flags |= REBASE_FORCE;
 892         }
 893
 894         if (options.keep_empty)
 895                 imply_interactive(&options, "--keep-empty");
 896
 897         if (gpg_sign) {
 898                 free(options.gpg_sign_opt);
 899                 options.gpg_sign_opt = xstrfmt("-S%s", gpg_sign);
 900         }
 901
 902         if (opt_c >= 0)
 903                 strbuf_addf(&options.git_am_opt, " -C%d", opt_c);
 904
 905         if (whitespace.nr) {
 906                 int i;
 907
 908                 for (i = 0; i < whitespace.nr; i++) {
 909                         const char *item = whitespace.items[i].string;
 910
 911                         strbuf_addf(&options.git_am_opt, " --whitespace=%s",
 912                                     item);
 913
 914                         if ((!strcmp(item, "fix")) || (!strcmp(item, "strip")))
 915                                 options.flags |= REBASE_FORCE;
 916                 }
 917         }
 918
 919         switch (options.type) {
 920         case REBASE_MERGE:
 921         case REBASE_INTERACTIVE:
 922         case REBASE_PRESERVE_MERGES:
 923                 options.state_dir = merge_dir();
 924                 break;
 925         case REBASE_AM:
 926                 options.state_dir = apply_dir();
 927                 break;
 928         default:
 929                 /* the default rebase backend is `--am` */
 930                 options.type = REBASE_AM;
 931                 options.state_dir = apply_dir();
 932                 break;
 933         }
 934
 935         if (options.signoff) {
 936                 if (options.type == REBASE_PRESERVE_MERGES)
 937                         die("cannot combine '--signoff' with "
 938                             "'--preserve-merges'");
 939                 strbuf_addstr(&options.git_am_opt, " --signoff");
 940                 options.flags |= REBASE_FORCE;
 941         }
 942
 943         if (!options.root) {
 944                 if (argc < 1)
 945                         die("TODO: handle @{upstream}");
 946                 else {
 947                         options.upstream_name = argv[0];
 948                         argc--;
 949                         argv++;
 950                         if (!strcmp(options.upstream_name, "-"))
 951                                 options.upstream_name = "@{-1}";
 952                 }
 953                 options.upstream = peel_committish(options.upstream_name);
 954                 if (!options.upstream)
 955                         die(_("invalid upstream '%s'"), options.upstream_name);
 956                 options.upstream_arg = options.upstream_name;
 957         } else
 958                 die("TODO: upstream for --root");
 959
 960         /* Make sure the branch to rebase onto is valid. */
 961         if (!options.onto_name)
 962                 options.onto_name = options.upstream_name;
 963         if (strstr(options.onto_name, "...")) {
 964                 if (get_oid_mb(options.onto_name, &merge_base) < 0)
 965                         die(_("'%s': need exactly one merge base"),
 966                             options.onto_name);
 967                 options.onto = lookup_commit_or_die(&merge_base,
 968                                                     options.onto_name);
 969         } else {
 970                 options.onto = peel_committish(options.onto_name);
 971                 if (!options.onto)
 972                         die(_("Does not point to a valid commit '%s'"),
 973                                 options.onto_name);
 974         }
 975
 976         /*
 977          * If the branch to rebase is given, that is the branch we will rebase
 978          * branch_name -- branch/commit being rebased, or
 979          *                HEAD (already detached)
 980          * orig_head -- commit object name of tip of the branch before rebasing
 981          * head_name -- refs/heads/<that-branch> or NULL (detached HEAD)
 982          */
 983         if (argc == 1) {
 984                 /* Is it "rebase other branchname" or "rebase other commit"? */
 985                 branch_name = argv[0];
 986                 options.switch_to = argv[0];
 987
 988                 /* Is it a local branch? */
 989                 strbuf_reset(&buf);
 990                 strbuf_addf(&buf, "refs/heads/%s", branch_name);
 991                 if (!read_ref(buf.buf, &options.orig_head))
 992                         options.head_name = xstrdup(buf.buf);
 993                 /* If not is it a valid ref (branch or commit)? */
 994                 else if (!get_oid(branch_name, &options.orig_head))
 995                         options.head_name = NULL;
 996                 else
 997                         die(_("fatal: no such branch/commit '%s'"),
 998                             branch_name);
 999         } else if (argc == 0) {
1000                 /* Do not need to switch branches, we are already on it. */
1001                 options.head_name =
1002                         xstrdup_or_null(resolve_ref_unsafe("HEAD", 0, NULL,
1003                                          &flags));
1004                 if (!options.head_name)
1005                         die(_("No such ref: %s"), "HEAD");
1006                 if (flags & REF_ISSYMREF) {
1007                         if (!skip_prefix(options.head_name,
1008                                          "refs/heads/", &branch_name))
1009                                 branch_name = options.head_name;
1010
1011                 } else {
1012                         free(options.head_name);
1013                         options.head_name = NULL;
1014                         branch_name = "HEAD";
1015                 }
1016                 if (get_oid("HEAD", &options.orig_head))
1017                         die(_("Could not resolve HEAD to a revision"));
1018         } else
1019                 BUG("unexpected number of arguments left to parse");
1020
1021         if (read_index(the_repository->index) < 0)
1022                 die(_("could not read index"));
1023
1024         if (options.autostash) {
1025                 struct lock_file lock_file = LOCK_INIT;
1026                 int fd;
1027
1028                 fd = hold_locked_index(&lock_file, 0);
1029                 refresh_cache(REFRESH_QUIET);
1030                 if (0 <= fd)
1031                         update_index_if_able(&the_index, &lock_file);
1032                 rollback_lock_file(&lock_file);
1033
1034                 if (has_unstaged_changes(0) || has_uncommitted_changes(0)) {
1035                         const char *autostash =
1036                                 state_dir_path("autostash", &options);
1037                         struct child_process stash = CHILD_PROCESS_INIT;
1038                         struct object_id oid;
1039                         struct commit *head =
1040                                 lookup_commit_reference(the_repository,
1041                                                         &options.orig_head);
1042
1043                         argv_array_pushl(&stash.args,
1044                                          "stash", "create", "autostash", NULL);
1045                         stash.git_cmd = 1;
1046                         stash.no_stdin = 1;
1047                         strbuf_reset(&buf);
1048                         if (capture_command(&stash, &buf, GIT_MAX_HEXSZ))
1049                                 die(_("Cannot autostash"));
1050                         strbuf_trim_trailing_newline(&buf);
1051                         if (get_oid(buf.buf, &oid))
1052                                 die(_("Unexpected stash response: '%s'"),
1053                                     buf.buf);
1054                         strbuf_reset(&buf);
1055                         strbuf_add_unique_abbrev(&buf, &oid, DEFAULT_ABBREV);
1056
1057                         if (safe_create_leading_directories_const(autostash))
1058                                 die(_("Could not create directory for '%s'"),
1059                                     options.state_dir);
1060                         write_file(autostash, "%s", buf.buf);
1061                         printf(_("Created autostash: %s\n"), buf.buf);
1062                         if (reset_head(&head->object.oid, "reset --hard",
1063                                        NULL, 0) < 0)
1064                                 die(_("could not reset --hard"));
1065                         printf(_("HEAD is now at %s"),
1066                                find_unique_abbrev(&head->object.oid,
1067                                                   DEFAULT_ABBREV));
1068                         strbuf_reset(&buf);
1069                         pp_commit_easy(CMIT_FMT_ONELINE, head, &buf);
1070                         if (buf.len > 0)
1071                                 printf(" %s", buf.buf);
1072                         putchar('\n');
1073
1074                         if (discard_index(the_repository->index) < 0 ||
1075                                 read_index(the_repository->index) < 0)
1076                                 die(_("could not read index"));
1077                 }
1078         }
1079
1080         if (require_clean_work_tree("rebase",
1081                                     _("Please commit or stash them."), 1, 1)) {
1082                 ret = 1;
1083                 goto cleanup;
1084         }
1085
1086         /*
1087          * Now we are rebasing commits upstream..orig_head (or with --root,
1088          * everything leading up to orig_head) on top of onto.
1089          */
1090
1091         /*
1092          * Check if we are already based on onto with linear history,
1093          * but this should be done only when upstream and onto are the same
1094          * and if this is not an interactive rebase.
1095          */
1096         if (can_fast_forward(options.onto, &options.orig_head, &merge_base) &&
1097             !is_interactive(&options) && !options.restrict_revision &&
1098             !oidcmp(&options.upstream->object.oid, &options.onto->object.oid)) {
1099                 int flag;
1100
1101                 if (!(options.flags & REBASE_FORCE)) {
1102                         /* Lazily switch to the target branch if needed... */
1103                         if (options.switch_to) {
1104                                 struct object_id oid;
1105
1106                                 if (get_oid(options.switch_to, &oid) < 0) {
1107                                         ret = !!error(_("could not parse '%s'"),
1108                                                       options.switch_to);
1109                                         goto cleanup;
1110                                 }
1111
1112                                 strbuf_reset(&buf);
1113                                 strbuf_addf(&buf, "rebase: checkout %s",
1114                                             options.switch_to);
1115                                 if (reset_head(&oid, "checkout",
1116                                                options.head_name, 0) < 0) {
1117                                         ret = !!error(_("could not switch to "
1118                                                         "%s"),
1119                                                       options.switch_to);
1120                                         goto cleanup;
1121                                 }
1122                         }
1123
1124                         if (!(options.flags & REBASE_NO_QUIET))
1125                                 ; /* be quiet */
1126                         else if (!strcmp(branch_name, "HEAD") &&
1127                                  resolve_ref_unsafe("HEAD", 0, NULL, &flag))
1128                                 puts(_("HEAD is up to date."));
1129                         else
1130                                 printf(_("Current branch %s is up to date.\n"),
1131                                        branch_name);
1132                         ret = !!finish_rebase(&options);
1133                         goto cleanup;
1134                 } else if (!(options.flags & REBASE_NO_QUIET))
1135                         ; /* be quiet */
1136                 else if (!strcmp(branch_name, "HEAD") &&
1137                          resolve_ref_unsafe("HEAD", 0, NULL, &flag))
1138                         puts(_("HEAD is up to date, rebase forced."));
1139                 else
1140                         printf(_("Current branch %s is up to date, rebase "
1141                                  "forced.\n"), branch_name);
1142         }
1143
1144         /* If a hook exists, give it a chance to interrupt*/
1145         if (!ok_to_skip_pre_rebase &&
1146             run_hook_le(NULL, "pre-rebase", options.upstream_arg,
1147                         argc ? argv[0] : NULL, NULL))
1148                 die(_("The pre-rebase hook refused to rebase."));
1149
1150         if (options.flags & REBASE_DIFFSTAT) {
1151                 struct diff_options opts;
1152
1153                 if (options.flags & REBASE_VERBOSE)
1154                         printf(_("Changes from %s to %s:\n"),
1155                                 oid_to_hex(&merge_base),
1156                                 oid_to_hex(&options.onto->object.oid));
1157
1158                 /* We want color (if set), but no pager */
1159                 diff_setup(&opts);
1160                 opts.stat_width = -1; /* use full terminal width */
1161                 opts.stat_graph_width = -1; /* respect statGraphWidth config */
1162                 opts.output_format |=
1163                         DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
1164                 opts.detect_rename = DIFF_DETECT_RENAME;
1165                 diff_setup_done(&opts);
1166                 diff_tree_oid(&merge_base, &options.onto->object.oid,
1167                               "", &opts);
1168                 diffcore_std(&opts);
1169                 diff_flush(&opts);
1170         }
1171
1172         if (is_interactive(&options))
1173                 goto run_rebase;
1174
1175         /* Detach HEAD and reset the tree */
1176         if (options.flags & REBASE_NO_QUIET)
1177                 printf(_("First, rewinding head to replay your work on top of "
1178                          "it...\n"));
1179
1180         strbuf_addf(&msg, "rebase: checkout %s", options.onto_name);
1181         if (reset_head(&options.onto->object.oid, "checkout", NULL, 1))
1182                 die(_("Could not detach HEAD"));
1183         strbuf_release(&msg);
1184
1185         strbuf_addf(&revisions, "%s..%s",
1186                     options.root ? oid_to_hex(&options.onto->object.oid) :
1187                     (options.restrict_revision ?
1188                      oid_to_hex(&options.restrict_revision->object.oid) :
1189                      oid_to_hex(&options.upstream->object.oid)),
1190                     oid_to_hex(&options.orig_head));
1191
1192         options.revisions = revisions.buf;
1193
1194 run_rebase:
1195         ret = !!run_specific_rebase(&options);
1196
1197 cleanup:
1198         strbuf_release(&revisions);
1199         free(options.head_name);
1200         free(options.gpg_sign_opt);
1201         return ret;
1202 }