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 object_id *squash_onto;
  80         struct commit *restrict_revision;
  81         int dont_finish_rebase;
  82         enum {
  83                 REBASE_NO_QUIET = 1<<0,
  84                 REBASE_VERBOSE = 1<<1,
  85                 REBASE_DIFFSTAT = 1<<2,
  86                 REBASE_FORCE = 1<<3,
  87                 REBASE_INTERACTIVE_EXPLICIT = 1<<4,
  88         } flags;
  89         struct strbuf git_am_opt;
  90         const char *action;
  91         int signoff;
  92         int allow_rerere_autoupdate;
  93         int keep_empty;
  94         int autosquash;
  95         char *gpg_sign_opt;
  96         int autostash;
  97         char *cmd;
  98         int allow_empty_message;
  99         int rebase_merges, rebase_cousins;
 100         char *strategy, *strategy_opts;
 101 };
 102
 103 static int is_interactive(struct rebase_options *opts)
 104 {
 105         return opts->type == REBASE_INTERACTIVE ||
 106                 opts->type == REBASE_PRESERVE_MERGES;
 107 }
 108
 109 static void imply_interactive(struct rebase_options *opts, const char *option)
 110 {
 111         switch (opts->type) {
 112         case REBASE_AM:
 113                 die(_("%s requires an interactive rebase"), option);
 114                 break;
 115         case REBASE_INTERACTIVE:
 116         case REBASE_PRESERVE_MERGES:
 117                 break;
 118         case REBASE_MERGE:
 119                 /* we silently *upgrade* --merge to --interactive if needed */
 120         default:
 121                 opts->type = REBASE_INTERACTIVE; /* implied */
 122                 break;
 123         }
 124 }
 125
 126 /* Returns the filename prefixed by the state_dir */
 127 static const char *state_dir_path(const char *filename, struct rebase_options *opts)
 128 {
 129         static struct strbuf path = STRBUF_INIT;
 130         static size_t prefix_len;
 131
 132         if (!prefix_len) {
 133                 strbuf_addf(&path, "%s/", opts->state_dir);
 134                 prefix_len = path.len;
 135         }
 136
 137         strbuf_setlen(&path, prefix_len);
 138         strbuf_addstr(&path, filename);
 139         return path.buf;
 140 }
 141
 142 /* Read one file, then strip line endings */
 143 static int read_one(const char *path, struct strbuf *buf)
 144 {
 145         if (strbuf_read_file(buf, path, 0) < 0)
 146                 return error_errno(_("could not read '%s'"), path);
 147         strbuf_trim_trailing_newline(buf);
 148         return 0;
 149 }
 150
 151 /* Initialize the rebase options from the state directory. */
 152 static int read_basic_state(struct rebase_options *opts)
 153 {
 154         struct strbuf head_name = STRBUF_INIT;
 155         struct strbuf buf = STRBUF_INIT;
 156         struct object_id oid;
 157
 158         if (read_one(state_dir_path("head-name", opts), &head_name) ||
 159             read_one(state_dir_path("onto", opts), &buf))
 160                 return -1;
 161         opts->head_name = starts_with(head_name.buf, "refs/") ?
 162                 xstrdup(head_name.buf) : NULL;
 163         strbuf_release(&head_name);
 164         if (get_oid(buf.buf, &oid))
 165                 return error(_("could not get 'onto': '%s'"), buf.buf);
 166         opts->onto = lookup_commit_or_die(&oid, buf.buf);
 167
 168         /*
 169          * We always write to orig-head, but interactive rebase used to write to
 170          * head. Fall back to reading from head to cover for the case that the
 171          * user upgraded git with an ongoing interactive rebase.
 172          */
 173         strbuf_reset(&buf);
 174         if (file_exists(state_dir_path("orig-head", opts))) {
 175                 if (read_one(state_dir_path("orig-head", opts), &buf))
 176                         return -1;
 177         } else if (read_one(state_dir_path("head", opts), &buf))
 178                 return -1;
 179         if (get_oid(buf.buf, &opts->orig_head))
 180                 return error(_("invalid orig-head: '%s'"), buf.buf);
 181
 182         strbuf_reset(&buf);
 183         if (read_one(state_dir_path("quiet", opts), &buf))
 184                 return -1;
 185         if (buf.len)
 186                 opts->flags &= ~REBASE_NO_QUIET;
 187         else
 188                 opts->flags |= REBASE_NO_QUIET;
 189
 190         if (file_exists(state_dir_path("verbose", opts)))
 191                 opts->flags |= REBASE_VERBOSE;
 192
 193         if (file_exists(state_dir_path("signoff", opts))) {
 194                 opts->signoff = 1;
 195                 opts->flags |= REBASE_FORCE;
 196         }
 197
 198         if (file_exists(state_dir_path("allow_rerere_autoupdate", opts))) {
 199                 strbuf_reset(&buf);
 200                 if (read_one(state_dir_path("allow_rerere_autoupdate", opts),
 201                             &buf))
 202                         return -1;
 203                 if (!strcmp(buf.buf, "--rerere-autoupdate"))
 204                         opts->allow_rerere_autoupdate = 1;
 205                 else if (!strcmp(buf.buf, "--no-rerere-autoupdate"))
 206                         opts->allow_rerere_autoupdate = 0;
 207                 else
 208                         warning(_("ignoring invalid allow_rerere_autoupdate: "
 209                                   "'%s'"), buf.buf);
 210         } else
 211                 opts->allow_rerere_autoupdate = -1;
 212
 213         if (file_exists(state_dir_path("gpg_sign_opt", opts))) {
 214                 strbuf_reset(&buf);
 215                 if (read_one(state_dir_path("gpg_sign_opt", opts),
 216                             &buf))
 217                         return -1;
 218                 free(opts->gpg_sign_opt);
 219                 opts->gpg_sign_opt = xstrdup(buf.buf);
 220         }
 221
 222         if (file_exists(state_dir_path("strategy", opts))) {
 223                 strbuf_reset(&buf);
 224                 if (read_one(state_dir_path("strategy", opts), &buf))
 225                         return -1;
 226                 free(opts->strategy);
 227                 opts->strategy = xstrdup(buf.buf);
 228         }
 229
 230         if (file_exists(state_dir_path("strategy_opts", opts))) {
 231                 strbuf_reset(&buf);
 232                 if (read_one(state_dir_path("strategy_opts", opts), &buf))
 233                         return -1;
 234                 free(opts->strategy_opts);
 235                 opts->strategy_opts = xstrdup(buf.buf);
 236         }
 237
 238         strbuf_release(&buf);
 239
 240         return 0;
 241 }
 242
 243 static int apply_autostash(struct rebase_options *opts)
 244 {
 245         const char *path = state_dir_path("autostash", opts);
 246         struct strbuf autostash = STRBUF_INIT;
 247         struct child_process stash_apply = CHILD_PROCESS_INIT;
 248
 249         if (!file_exists(path))
 250                 return 0;
 251
 252         if (read_one(state_dir_path("autostash", opts), &autostash))
 253                 return error(_("Could not read '%s'"), path);
 254         argv_array_pushl(&stash_apply.args,
 255                          "stash", "apply", autostash.buf, NULL);
 256         stash_apply.git_cmd = 1;
 257         stash_apply.no_stderr = stash_apply.no_stdout =
 258                 stash_apply.no_stdin = 1;
 259         if (!run_command(&stash_apply))
 260                 printf(_("Applied autostash.\n"));
 261         else {
 262                 struct argv_array args = ARGV_ARRAY_INIT;
 263                 int res = 0;
 264
 265                 argv_array_pushl(&args,
 266                                  "stash", "store", "-m", "autostash", "-q",
 267                                  autostash.buf, NULL);
 268                 if (run_command_v_opt(args.argv, RUN_GIT_CMD))
 269                         res = error(_("Cannot store %s"), autostash.buf);
 270                 argv_array_clear(&args);
 271                 strbuf_release(&autostash);
 272                 if (res)
 273                         return res;
 274
 275                 fprintf(stderr,
 276                         _("Applying autostash resulted in conflicts.\n"
 277                           "Your changes are safe in the stash.\n"
 278                           "You can run \"git stash pop\" or \"git stash drop\" "
 279                           "at any time.\n"));
 280         }
 281
 282         strbuf_release(&autostash);
 283         return 0;
 284 }
 285
 286 static int finish_rebase(struct rebase_options *opts)
 287 {
 288         struct strbuf dir = STRBUF_INIT;
 289         const char *argv_gc_auto[] = { "gc", "--auto", NULL };
 290
 291         delete_ref(NULL, "REBASE_HEAD", NULL, REF_NO_DEREF);
 292         apply_autostash(opts);
 293         close_all_packs(the_repository->objects);
 294         /*
 295          * We ignore errors in 'gc --auto', since the
 296          * user should see them.
 297          */
 298         run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
 299         strbuf_addstr(&dir, opts->state_dir);
 300         remove_dir_recursively(&dir, 0);
 301         strbuf_release(&dir);
 302
 303         return 0;
 304 }
 305
 306 static struct commit *peel_committish(const char *name)
 307 {
 308         struct object *obj;
 309         struct object_id oid;
 310
 311         if (get_oid(name, &oid))
 312                 return NULL;
 313         obj = parse_object(the_repository, &oid);
 314         return (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
 315 }
 316
 317 static void add_var(struct strbuf *buf, const char *name, const char *value)
 318 {
 319         if (!value)
 320                 strbuf_addf(buf, "unset %s; ", name);
 321         else {
 322                 strbuf_addf(buf, "%s=", name);
 323                 sq_quote_buf(buf, value);
 324                 strbuf_addstr(buf, "; ");
 325         }
 326 }
 327
 328 static int run_specific_rebase(struct rebase_options *opts)
 329 {
 330         const char *argv[] = { NULL, NULL };
 331         struct strbuf script_snippet = STRBUF_INIT;
 332         int status;
 333         const char *backend, *backend_func;
 334
 335         add_var(&script_snippet, "GIT_DIR", absolute_path(get_git_dir()));
 336         add_var(&script_snippet, "state_dir", opts->state_dir);
 337
 338         add_var(&script_snippet, "upstream_name", opts->upstream_name);
 339         add_var(&script_snippet, "upstream", opts->upstream ?
 340                 oid_to_hex(&opts->upstream->object.oid) : NULL);
 341         add_var(&script_snippet, "head_name",
 342                 opts->head_name ? opts->head_name : "detached HEAD");
 343         add_var(&script_snippet, "orig_head", oid_to_hex(&opts->orig_head));
 344         add_var(&script_snippet, "onto", opts->onto ?
 345                 oid_to_hex(&opts->onto->object.oid) : NULL);
 346         add_var(&script_snippet, "onto_name", opts->onto_name);
 347         add_var(&script_snippet, "revisions", opts->revisions);
 348         add_var(&script_snippet, "restrict_revision", opts->restrict_revision ?
 349                 oid_to_hex(&opts->restrict_revision->object.oid) : NULL);
 350         add_var(&script_snippet, "GIT_QUIET",
 351                 opts->flags & REBASE_NO_QUIET ? "" : "t");
 352         add_var(&script_snippet, "git_am_opt", opts->git_am_opt.buf);
 353         add_var(&script_snippet, "verbose",
 354                 opts->flags & REBASE_VERBOSE ? "t" : "");
 355         add_var(&script_snippet, "diffstat",
 356                 opts->flags & REBASE_DIFFSTAT ? "t" : "");
 357         add_var(&script_snippet, "force_rebase",
 358                 opts->flags & REBASE_FORCE ? "t" : "");
 359         if (opts->switch_to)
 360                 add_var(&script_snippet, "switch_to", opts->switch_to);
 361         add_var(&script_snippet, "action", opts->action ? opts->action : "");
 362         add_var(&script_snippet, "signoff", opts->signoff ? "--signoff" : "");
 363         add_var(&script_snippet, "allow_rerere_autoupdate",
 364                 opts->allow_rerere_autoupdate < 0 ? "" :
 365                 opts->allow_rerere_autoupdate ?
 366                 "--rerere-autoupdate" : "--no-rerere-autoupdate");
 367         add_var(&script_snippet, "keep_empty", opts->keep_empty ? "yes" : "");
 368         add_var(&script_snippet, "autosquash", opts->autosquash ? "t" : "");
 369         add_var(&script_snippet, "gpg_sign_opt", opts->gpg_sign_opt);
 370         add_var(&script_snippet, "cmd", opts->cmd);
 371         add_var(&script_snippet, "allow_empty_message",
 372                 opts->allow_empty_message ?  "--allow-empty-message" : "");
 373         add_var(&script_snippet, "rebase_merges",
 374                 opts->rebase_merges ? "t" : "");
 375         add_var(&script_snippet, "rebase_cousins",
 376                 opts->rebase_cousins ? "t" : "");
 377         add_var(&script_snippet, "strategy", opts->strategy);
 378         add_var(&script_snippet, "strategy_opts", opts->strategy_opts);
 379         add_var(&script_snippet, "rebase_root", opts->root ? "t" : "");
 380         add_var(&script_snippet, "squash_onto",
 381                 opts->squash_onto ? oid_to_hex(opts->squash_onto) : "");
 382
 383         switch (opts->type) {
 384         case REBASE_AM:
 385                 backend = "git-rebase--am";
 386                 backend_func = "git_rebase__am";
 387                 break;
 388         case REBASE_INTERACTIVE:
 389                 backend = "git-rebase--interactive";
 390                 backend_func = "git_rebase__interactive";
 391                 break;
 392         case REBASE_MERGE:
 393                 backend = "git-rebase--merge";
 394                 backend_func = "git_rebase__merge";
 395                 break;
 396         case REBASE_PRESERVE_MERGES:
 397                 backend = "git-rebase--preserve-merges";
 398                 backend_func = "git_rebase__preserve_merges";
 399                 break;
 400         default:
 401                 BUG("Unhandled rebase type %d", opts->type);
 402                 break;
 403         }
 404
 405         strbuf_addf(&script_snippet,
 406                     ". git-sh-setup && . git-rebase--common &&"
 407                     " . %s && %s", backend, backend_func);
 408         argv[0] = script_snippet.buf;
 409
 410         status = run_command_v_opt(argv, RUN_USING_SHELL);
 411         if (opts->dont_finish_rebase)
 412                 ; /* do nothing */
 413         else if (status == 0) {
 414                 if (!file_exists(state_dir_path("stopped-sha", opts)))
 415                         finish_rebase(opts);
 416         } else if (status == 2) {
 417                 struct strbuf dir = STRBUF_INIT;
 418
 419                 apply_autostash(opts);
 420                 strbuf_addstr(&dir, opts->state_dir);
 421                 remove_dir_recursively(&dir, 0);
 422                 strbuf_release(&dir);
 423                 die("Nothing to do");
 424         }
 425
 426         strbuf_release(&script_snippet);
 427
 428         return status ? -1 : 0;
 429 }
 430
 431 #define GIT_REFLOG_ACTION_ENVIRONMENT "GIT_REFLOG_ACTION"
 432
 433 static int reset_head(struct object_id *oid, const char *action,
 434                       const char *switch_to_branch, int detach_head,
 435                       const char *reflog_orig_head, const char *reflog_head)
 436 {
 437         struct object_id head_oid;
 438         struct tree_desc desc;
 439         struct lock_file lock = LOCK_INIT;
 440         struct unpack_trees_options unpack_tree_opts;
 441         struct tree *tree;
 442         const char *reflog_action;
 443         struct strbuf msg = STRBUF_INIT;
 444         size_t prefix_len;
 445         struct object_id *orig = NULL, oid_orig,
 446                 *old_orig = NULL, oid_old_orig;
 447         int ret = 0;
 448
 449         if (switch_to_branch && !starts_with(switch_to_branch, "refs/"))
 450                 BUG("Not a fully qualified branch: '%s'", switch_to_branch);
 451
 452         if (hold_locked_index(&lock, LOCK_REPORT_ON_ERROR) < 0)
 453                 return -1;
 454
 455         if (!oid) {
 456                 if (get_oid("HEAD", &head_oid)) {
 457                         rollback_lock_file(&lock);
 458                         return error(_("could not determine HEAD revision"));
 459                 }
 460                 oid = &head_oid;
 461         }
 462
 463         memset(&unpack_tree_opts, 0, sizeof(unpack_tree_opts));
 464         setup_unpack_trees_porcelain(&unpack_tree_opts, action);
 465         unpack_tree_opts.head_idx = 1;
 466         unpack_tree_opts.src_index = the_repository->index;
 467         unpack_tree_opts.dst_index = the_repository->index;
 468         unpack_tree_opts.fn = oneway_merge;
 469         unpack_tree_opts.update = 1;
 470         unpack_tree_opts.merge = 1;
 471         if (!detach_head)
 472                 unpack_tree_opts.reset = 1;
 473
 474         if (read_index_unmerged(the_repository->index) < 0) {
 475                 rollback_lock_file(&lock);
 476                 return error(_("could not read index"));
 477         }
 478
 479         if (!fill_tree_descriptor(&desc, oid)) {
 480                 error(_("failed to find tree of %s"), oid_to_hex(oid));
 481                 rollback_lock_file(&lock);
 482                 free((void *)desc.buffer);
 483                 return -1;
 484         }
 485
 486         if (unpack_trees(1, &desc, &unpack_tree_opts)) {
 487                 rollback_lock_file(&lock);
 488                 free((void *)desc.buffer);
 489                 return -1;
 490         }
 491
 492         tree = parse_tree_indirect(oid);
 493         prime_cache_tree(the_repository->index, tree);
 494
 495         if (write_locked_index(the_repository->index, &lock, COMMIT_LOCK) < 0)
 496                 ret = error(_("could not write index"));
 497         free((void *)desc.buffer);
 498
 499         if (ret)
 500                 return ret;
 501
 502         reflog_action = getenv(GIT_REFLOG_ACTION_ENVIRONMENT);
 503         strbuf_addf(&msg, "%s: ", reflog_action ? reflog_action : "rebase");
 504         prefix_len = msg.len;
 505
 506         if (!get_oid("ORIG_HEAD", &oid_old_orig))
 507                 old_orig = &oid_old_orig;
 508         if (!get_oid("HEAD", &oid_orig)) {
 509                 orig = &oid_orig;
 510                 if (!reflog_orig_head) {
 511                         strbuf_addstr(&msg, "updating ORIG_HEAD");
 512                         reflog_orig_head = msg.buf;
 513                 }
 514                 update_ref(reflog_orig_head, "ORIG_HEAD", orig, old_orig, 0,
 515                            UPDATE_REFS_MSG_ON_ERR);
 516         } else if (old_orig)
 517                 delete_ref(NULL, "ORIG_HEAD", old_orig, 0);
 518         if (!reflog_head) {
 519                 strbuf_setlen(&msg, prefix_len);
 520                 strbuf_addstr(&msg, "updating HEAD");
 521                 reflog_head = msg.buf;
 522         }
 523         if (!switch_to_branch)
 524                 ret = update_ref(reflog_head, "HEAD", oid, orig, REF_NO_DEREF,
 525                                  UPDATE_REFS_MSG_ON_ERR);
 526         else {
 527                 ret = create_symref("HEAD", switch_to_branch, msg.buf);
 528                 if (!ret)
 529                         ret = update_ref(reflog_head, "HEAD", oid, NULL, 0,
 530                                          UPDATE_REFS_MSG_ON_ERR);
 531         }
 532
 533         strbuf_release(&msg);
 534         return ret;
 535 }
 536
 537 static int rebase_config(const char *var, const char *value, void *data)
 538 {
 539         struct rebase_options *opts = data;
 540
 541         if (!strcmp(var, "rebase.stat")) {
 542                 if (git_config_bool(var, value))
 543                         opts->flags |= REBASE_DIFFSTAT;
 544                 else
 545                         opts->flags &= !REBASE_DIFFSTAT;
 546                 return 0;
 547         }
 548
 549         if (!strcmp(var, "rebase.autosquash")) {
 550                 opts->autosquash = git_config_bool(var, value);
 551                 return 0;
 552         }
 553
 554         if (!strcmp(var, "commit.gpgsign")) {
 555                 free(opts->gpg_sign_opt);
 556                 opts->gpg_sign_opt = git_config_bool(var, value) ?
 557                         xstrdup("-S") : NULL;
 558                 return 0;
 559         }
 560
 561         if (!strcmp(var, "rebase.autostash")) {
 562                 opts->autostash = git_config_bool(var, value);
 563                 return 0;
 564         }
 565
 566         return git_default_config(var, value, data);
 567 }
 568
 569 /*
 570  * Determines whether the commits in from..to are linear, i.e. contain
 571  * no merge commits. This function *expects* `from` to be an ancestor of
 572  * `to`.
 573  */
 574 static int is_linear_history(struct commit *from, struct commit *to)
 575 {
 576         while (to && to != from) {
 577                 parse_commit(to);
 578                 if (!to->parents)
 579                         return 1;
 580                 if (to->parents->next)
 581                         return 0;
 582                 to = to->parents->item;
 583         }
 584         return 1;
 585 }
 586
 587 static int can_fast_forward(struct commit *onto, struct object_id *head_oid,
 588                             struct object_id *merge_base)
 589 {
 590         struct commit *head = lookup_commit(the_repository, head_oid);
 591         struct commit_list *merge_bases;
 592         int res;
 593
 594         if (!head)
 595                 return 0;
 596
 597         merge_bases = get_merge_bases(onto, head);
 598         if (merge_bases && !merge_bases->next) {
 599                 oidcpy(merge_base, &merge_bases->item->object.oid);
 600                 res = !oidcmp(merge_base, &onto->object.oid);
 601         } else {
 602                 oidcpy(merge_base, &null_oid);
 603                 res = 0;
 604         }
 605         free_commit_list(merge_bases);
 606         return res && is_linear_history(onto, head);
 607 }
 608
 609 /* -i followed by -m is still -i */
 610 static int parse_opt_merge(const struct option *opt, const char *arg, int unset)
 611 {
 612         struct rebase_options *opts = opt->value;
 613
 614         if (!is_interactive(opts))
 615                 opts->type = REBASE_MERGE;
 616
 617         return 0;
 618 }
 619
 620 /* -i followed by -p is still explicitly interactive, but -p alone is not */
 621 static int parse_opt_interactive(const struct option *opt, const char *arg,
 622                                  int unset)
 623 {
 624         struct rebase_options *opts = opt->value;
 625
 626         opts->type = REBASE_INTERACTIVE;
 627         opts->flags |= REBASE_INTERACTIVE_EXPLICIT;
 628
 629         return 0;
 630 }
 631
 632 static void NORETURN error_on_missing_default_upstream(void)
 633 {
 634         struct branch *current_branch = branch_get(NULL);
 635
 636         printf(_("%s\n"
 637                  "Please specify which branch you want to rebase against.\n"
 638                  "See git-rebase(1) for details.\n"
 639                  "\n"
 640                  "    git rebase '<branch>'\n"
 641                  "\n"),
 642                 current_branch ? _("There is no tracking information for "
 643                         "the current branch.") :
 644                         _("You are not currently on a branch."));
 645
 646         if (current_branch) {
 647                 const char *remote = current_branch->remote_name;
 648
 649                 if (!remote)
 650                         remote = _("<remote>");
 651
 652                 printf(_("If you wish to set tracking information for this "
 653                          "branch you can do so with:\n"
 654                          "\n"
 655                          "    git branch --set-upstream-to=%s/<branch> %s\n"
 656                          "\n"),
 657                        remote, current_branch->name);
 658         }
 659         exit(1);
 660 }
 661
 662 int cmd_rebase(int argc, const char **argv, const char *prefix)
 663 {
 664         struct rebase_options options = {
 665                 .type = REBASE_UNSPECIFIED,
 666                 .flags = REBASE_NO_QUIET,
 667                 .git_am_opt = STRBUF_INIT,
 668                 .allow_rerere_autoupdate  = -1,
 669                 .allow_empty_message = 1,
 670         };
 671         const char *branch_name;
 672         int ret, flags, total_argc, in_progress = 0;
 673         int ok_to_skip_pre_rebase = 0;
 674         struct strbuf msg = STRBUF_INIT;
 675         struct strbuf revisions = STRBUF_INIT;
 676         struct strbuf buf = STRBUF_INIT;
 677         struct object_id merge_base;
 678         enum {
 679                 NO_ACTION,
 680                 ACTION_CONTINUE,
 681                 ACTION_SKIP,
 682                 ACTION_ABORT,
 683                 ACTION_QUIT,
 684                 ACTION_EDIT_TODO,
 685                 ACTION_SHOW_CURRENT_PATCH,
 686         } action = NO_ACTION;
 687         int committer_date_is_author_date = 0;
 688         int ignore_date = 0;
 689         int ignore_whitespace = 0;
 690         const char *gpg_sign = NULL;
 691         int opt_c = -1;
 692         struct string_list whitespace = STRING_LIST_INIT_NODUP;
 693         struct string_list exec = STRING_LIST_INIT_NODUP;
 694         const char *rebase_merges = NULL;
 695         int fork_point = -1;
 696         struct string_list strategy_options = STRING_LIST_INIT_NODUP;
 697         struct object_id squash_onto;
 698         char *squash_onto_name = NULL;
 699         struct option builtin_rebase_options[] = {
 700                 OPT_STRING(0, "onto", &options.onto_name,
 701                            N_("revision"),
 702                            N_("rebase onto given branch instead of upstream")),
 703                 OPT_BOOL(0, "no-verify", &ok_to_skip_pre_rebase,
 704                          N_("allow pre-rebase hook to run")),
 705                 OPT_NEGBIT('q', "quiet", &options.flags,
 706                            N_("be quiet. implies --no-stat"),
 707                            REBASE_NO_QUIET| REBASE_VERBOSE | REBASE_DIFFSTAT),
 708                 OPT_BIT('v', "verbose", &options.flags,
 709                         N_("display a diffstat of what changed upstream"),
 710                         REBASE_NO_QUIET | REBASE_VERBOSE | REBASE_DIFFSTAT),
 711                 {OPTION_NEGBIT, 'n', "no-stat", &options.flags, NULL,
 712                         N_("do not show diffstat of what changed upstream"),
 713                         PARSE_OPT_NOARG, NULL, REBASE_DIFFSTAT },
 714                 OPT_BOOL(0, "ignore-whitespace", &ignore_whitespace,
 715                          N_("passed to 'git apply'")),
 716                 OPT_BOOL(0, "signoff", &options.signoff,
 717                          N_("add a Signed-off-by: line to each commit")),
 718                 OPT_BOOL(0, "committer-date-is-author-date",
 719                          &committer_date_is_author_date,
 720                          N_("passed to 'git am'")),
 721                 OPT_BOOL(0, "ignore-date", &ignore_date,
 722                          N_("passed to 'git am'")),
 723                 OPT_BIT('f', "force-rebase", &options.flags,
 724                         N_("cherry-pick all commits, even if unchanged"),
 725                         REBASE_FORCE),
 726                 OPT_BIT(0, "no-ff", &options.flags,
 727                         N_("cherry-pick all commits, even if unchanged"),
 728                         REBASE_FORCE),
 729                 OPT_CMDMODE(0, "continue", &action, N_("continue"),
 730                             ACTION_CONTINUE),
 731                 OPT_CMDMODE(0, "skip", &action,
 732                             N_("skip current patch and continue"), ACTION_SKIP),
 733                 OPT_CMDMODE(0, "abort", &action,
 734                             N_("abort and check out the original branch"),
 735                             ACTION_ABORT),
 736                 OPT_CMDMODE(0, "quit", &action,
 737                             N_("abort but keep HEAD where it is"), ACTION_QUIT),
 738                 OPT_CMDMODE(0, "edit-todo", &action, N_("edit the todo list "
 739                             "during an interactive rebase"), ACTION_EDIT_TODO),
 740                 OPT_CMDMODE(0, "show-current-patch", &action,
 741                             N_("show the patch file being applied or merged"),
 742                             ACTION_SHOW_CURRENT_PATCH),
 743                 { OPTION_CALLBACK, 'm', "merge", &options, NULL,
 744                         N_("use merging strategies to rebase"),
 745                         PARSE_OPT_NOARG | PARSE_OPT_NONEG,
 746                         parse_opt_merge },
 747                 { OPTION_CALLBACK, 'i', "interactive", &options, NULL,
 748                         N_("let the user edit the list of commits to rebase"),
 749                         PARSE_OPT_NOARG | PARSE_OPT_NONEG,
 750                         parse_opt_interactive },
 751                 OPT_SET_INT('p', "preserve-merges", &options.type,
 752                             N_("try to recreate merges instead of ignoring "
 753                                "them"), REBASE_PRESERVE_MERGES),
 754                 OPT_BOOL(0, "rerere-autoupdate",
 755                          &options.allow_rerere_autoupdate,
 756                          N_("allow rerere to update index  with resolved "
 757                             "conflict")),
 758                 OPT_BOOL('k', "keep-empty", &options.keep_empty,
 759                          N_("preserve empty commits during rebase")),
 760                 OPT_BOOL(0, "autosquash", &options.autosquash,
 761                          N_("move commits that begin with "
 762                             "squash!/fixup! under -i")),
 763                 { OPTION_STRING, 'S', "gpg-sign", &gpg_sign, N_("key-id"),
 764                         N_("GPG-sign commits"),
 765                         PARSE_OPT_OPTARG, NULL, (intptr_t) "" },
 766                 OPT_STRING_LIST(0, "whitespace", &whitespace,
 767                                 N_("whitespace"), N_("passed to 'git apply'")),
 768                 OPT_SET_INT('C', NULL, &opt_c, N_("passed to 'git apply'"),
 769                             REBASE_AM),
 770                 OPT_BOOL(0, "autostash", &options.autostash,
 771                          N_("automatically stash/stash pop before and after")),
 772                 OPT_STRING_LIST('x', "exec", &exec, N_("exec"),
 773                                 N_("add exec lines after each commit of the "
 774                                    "editable list")),
 775                 OPT_BOOL(0, "allow-empty-message",
 776                          &options.allow_empty_message,
 777                          N_("allow rebasing commits with empty messages")),
 778                 {OPTION_STRING, 'r', "rebase-merges", &rebase_merges,
 779                         N_("mode"),
 780                         N_("try to rebase merges instead of skipping them"),
 781                         PARSE_OPT_OPTARG, NULL, (intptr_t)""},
 782                 OPT_BOOL(0, "fork-point", &fork_point,
 783                          N_("use 'merge-base --fork-point' to refine upstream")),
 784                 OPT_STRING('s', "strategy", &options.strategy,
 785                            N_("strategy"), N_("use the given merge strategy")),
 786                 OPT_STRING_LIST('X', "strategy-option", &strategy_options,
 787                                 N_("option"),
 788                                 N_("pass the argument through to the merge "
 789                                    "strategy")),
 790                 OPT_BOOL(0, "root", &options.root,
 791                          N_("rebase all reachable commits up to the root(s)")),
 792                 OPT_END(),
 793         };
 794
 795         /*
 796          * NEEDSWORK: Once the builtin rebase has been tested enough
 797          * and git-legacy-rebase.sh is retired to contrib/, this preamble
 798          * can be removed.
 799          */
 800
 801         if (!use_builtin_rebase()) {
 802                 const char *path = mkpath("%s/git-legacy-rebase",
 803                                           git_exec_path());
 804
 805                 if (sane_execvp(path, (char **)argv) < 0)
 806                         die_errno(_("could not exec %s"), path);
 807                 else
 808                         BUG("sane_execvp() returned???");
 809         }
 810
 811         if (argc == 2 && !strcmp(argv[1], "-h"))
 812                 usage_with_options(builtin_rebase_usage,
 813                                    builtin_rebase_options);
 814
 815         prefix = setup_git_directory();
 816         trace_repo_setup(prefix);
 817         setup_work_tree();
 818
 819         git_config(rebase_config, &options);
 820
 821         strbuf_reset(&buf);
 822         strbuf_addf(&buf, "%s/applying", apply_dir());
 823         if(file_exists(buf.buf))
 824                 die(_("It looks like 'git am' is in progress. Cannot rebase."));
 825
 826         if (is_directory(apply_dir())) {
 827                 options.type = REBASE_AM;
 828                 options.state_dir = apply_dir();
 829         } else if (is_directory(merge_dir())) {
 830                 strbuf_reset(&buf);
 831                 strbuf_addf(&buf, "%s/rewritten", merge_dir());
 832                 if (is_directory(buf.buf)) {
 833                         options.type = REBASE_PRESERVE_MERGES;
 834                         options.flags |= REBASE_INTERACTIVE_EXPLICIT;
 835                 } else {
 836                         strbuf_reset(&buf);
 837                         strbuf_addf(&buf, "%s/interactive", merge_dir());
 838                         if(file_exists(buf.buf)) {
 839                                 options.type = REBASE_INTERACTIVE;
 840                                 options.flags |= REBASE_INTERACTIVE_EXPLICIT;
 841                         } else
 842                                 options.type = REBASE_MERGE;
 843                 }
 844                 options.state_dir = merge_dir();
 845         }
 846
 847         if (options.type != REBASE_UNSPECIFIED)
 848                 in_progress = 1;
 849
 850         total_argc = argc;
 851         argc = parse_options(argc, argv, prefix,
 852                              builtin_rebase_options,
 853                              builtin_rebase_usage, 0);
 854
 855         if (action != NO_ACTION && total_argc != 2) {
 856                 usage_with_options(builtin_rebase_usage,
 857                                    builtin_rebase_options);
 858         }
 859
 860         if (argc > 2)
 861                 usage_with_options(builtin_rebase_usage,
 862                                    builtin_rebase_options);
 863
 864         if (action != NO_ACTION && !in_progress)
 865                 die(_("No rebase in progress?"));
 866
 867         if (action == ACTION_EDIT_TODO && !is_interactive(&options))
 868                 die(_("The --edit-todo action can only be used during "
 869                       "interactive rebase."));
 870
 871         switch (action) {
 872         case ACTION_CONTINUE: {
 873                 struct object_id head;
 874                 struct lock_file lock_file = LOCK_INIT;
 875                 int fd;
 876
 877                 options.action = "continue";
 878
 879                 /* Sanity check */
 880                 if (get_oid("HEAD", &head))
 881                         die(_("Cannot read HEAD"));
 882
 883                 fd = hold_locked_index(&lock_file, 0);
 884                 if (read_index(the_repository->index) < 0)
 885                         die(_("could not read index"));
 886                 refresh_index(the_repository->index, REFRESH_QUIET, NULL, NULL,
 887                               NULL);
 888                 if (0 <= fd)
 889                         update_index_if_able(the_repository->index,
 890                                              &lock_file);
 891                 rollback_lock_file(&lock_file);
 892
 893                 if (has_unstaged_changes(1)) {
 894                         puts(_("You must edit all merge conflicts and then\n"
 895                                "mark them as resolved using git add"));
 896                         exit(1);
 897                 }
 898                 if (read_basic_state(&options))
 899                         exit(1);
 900                 goto run_rebase;
 901         }
 902         case ACTION_SKIP: {
 903                 struct string_list merge_rr = STRING_LIST_INIT_DUP;
 904
 905                 options.action = "skip";
 906
 907                 rerere_clear(&merge_rr);
 908                 string_list_clear(&merge_rr, 1);
 909
 910                 if (reset_head(NULL, "reset", NULL, 0, NULL, NULL) < 0)
 911                         die(_("could not discard worktree changes"));
 912                 if (read_basic_state(&options))
 913                         exit(1);
 914                 goto run_rebase;
 915         }
 916         case ACTION_ABORT: {
 917                 struct string_list merge_rr = STRING_LIST_INIT_DUP;
 918                 options.action = "abort";
 919
 920                 rerere_clear(&merge_rr);
 921                 string_list_clear(&merge_rr, 1);
 922
 923                 if (read_basic_state(&options))
 924                         exit(1);
 925                 if (reset_head(&options.orig_head, "reset",
 926                                options.head_name, 0, NULL, NULL) < 0)
 927                         die(_("could not move back to %s"),
 928                             oid_to_hex(&options.orig_head));
 929                 ret = finish_rebase(&options);
 930                 goto cleanup;
 931         }
 932         case ACTION_QUIT: {
 933                 strbuf_reset(&buf);
 934                 strbuf_addstr(&buf, options.state_dir);
 935                 ret = !!remove_dir_recursively(&buf, 0);
 936                 if (ret)
 937                         die(_("could not remove '%s'"), options.state_dir);
 938                 goto cleanup;
 939         }
 940         case ACTION_EDIT_TODO:
 941                 options.action = "edit-todo";
 942                 options.dont_finish_rebase = 1;
 943                 goto run_rebase;
 944         case ACTION_SHOW_CURRENT_PATCH:
 945                 options.action = "show-current-patch";
 946                 options.dont_finish_rebase = 1;
 947                 goto run_rebase;
 948         case NO_ACTION:
 949                 break;
 950         default:
 951                 BUG("action: %d", action);
 952         }
 953
 954         /* Make sure no rebase is in progress */
 955         if (in_progress) {
 956                 const char *last_slash = strrchr(options.state_dir, '/');
 957                 const char *state_dir_base =
 958                         last_slash ? last_slash + 1 : options.state_dir;
 959                 const char *cmd_live_rebase =
 960                         "git rebase (--continue | --abort | --skip)";
 961                 strbuf_reset(&buf);
 962                 strbuf_addf(&buf, "rm -fr \"%s\"", options.state_dir);
 963                 die(_("It seems that there is already a %s directory, and\n"
 964                       "I wonder if you are in the middle of another rebase.  "
 965                       "If that is the\n"
 966                       "case, please try\n\t%s\n"
 967                       "If that is not the case, please\n\t%s\n"
 968                       "and run me again.  I am stopping in case you still "
 969                       "have something\n"
 970                       "valuable there.\n"),
 971                     state_dir_base, cmd_live_rebase, buf.buf);
 972         }
 973
 974         if (!(options.flags & REBASE_NO_QUIET))
 975                 strbuf_addstr(&options.git_am_opt, " -q");
 976
 977         if (committer_date_is_author_date) {
 978                 strbuf_addstr(&options.git_am_opt,
 979                               " --committer-date-is-author-date");
 980                 options.flags |= REBASE_FORCE;
 981         }
 982
 983         if (ignore_whitespace)
 984                 strbuf_addstr(&options.git_am_opt, " --ignore-whitespace");
 985
 986         if (ignore_date) {
 987                 strbuf_addstr(&options.git_am_opt, " --ignore-date");
 988                 options.flags |= REBASE_FORCE;
 989         }
 990
 991         if (options.keep_empty)
 992                 imply_interactive(&options, "--keep-empty");
 993
 994         if (gpg_sign) {
 995                 free(options.gpg_sign_opt);
 996                 options.gpg_sign_opt = xstrfmt("-S%s", gpg_sign);
 997         }
 998
 999         if (opt_c >= 0)
1000                 strbuf_addf(&options.git_am_opt, " -C%d", opt_c);
1001
1002         if (whitespace.nr) {
1003                 int i;
1004
1005                 for (i = 0; i < whitespace.nr; i++) {
1006                         const char *item = whitespace.items[i].string;
1007
1008                         strbuf_addf(&options.git_am_opt, " --whitespace=%s",
1009                                     item);
1010
1011                         if ((!strcmp(item, "fix")) || (!strcmp(item, "strip")))
1012                                 options.flags |= REBASE_FORCE;
1013                 }
1014         }
1015
1016         if (exec.nr) {
1017                 int i;
1018
1019                 imply_interactive(&options, "--exec");
1020
1021                 strbuf_reset(&buf);
1022                 for (i = 0; i < exec.nr; i++)
1023                         strbuf_addf(&buf, "exec %s\n", exec.items[i].string);
1024                 options.cmd = xstrdup(buf.buf);
1025         }
1026
1027         if (rebase_merges) {
1028                 if (!*rebase_merges)
1029                         ; /* default mode; do nothing */
1030                 else if (!strcmp("rebase-cousins", rebase_merges))
1031                         options.rebase_cousins = 1;
1032                 else if (strcmp("no-rebase-cousins", rebase_merges))
1033                         die(_("Unknown mode: %s"), rebase_merges);
1034                 options.rebase_merges = 1;
1035                 imply_interactive(&options, "--rebase-merges");
1036         }
1037
1038         if (strategy_options.nr) {
1039                 int i;
1040
1041                 if (!options.strategy)
1042                         options.strategy = "recursive";
1043
1044                 strbuf_reset(&buf);
1045                 for (i = 0; i < strategy_options.nr; i++)
1046                         strbuf_addf(&buf, " --%s",
1047                                     strategy_options.items[i].string);
1048                 options.strategy_opts = xstrdup(buf.buf);
1049         }
1050
1051         if (options.strategy) {
1052                 options.strategy = xstrdup(options.strategy);
1053                 switch (options.type) {
1054                 case REBASE_AM:
1055                         die(_("--strategy requires --merge or --interactive"));
1056                 case REBASE_MERGE:
1057                 case REBASE_INTERACTIVE:
1058                 case REBASE_PRESERVE_MERGES:
1059                         /* compatible */
1060                         break;
1061                 case REBASE_UNSPECIFIED:
1062                         options.type = REBASE_MERGE;
1063                         break;
1064                 default:
1065                         BUG("unhandled rebase type (%d)", options.type);
1066                 }
1067         }
1068
1069         if (options.root && !options.onto_name)
1070                 imply_interactive(&options, "--root without --onto");
1071
1072         switch (options.type) {
1073         case REBASE_MERGE:
1074         case REBASE_INTERACTIVE:
1075         case REBASE_PRESERVE_MERGES:
1076                 options.state_dir = merge_dir();
1077                 break;
1078         case REBASE_AM:
1079                 options.state_dir = apply_dir();
1080                 break;
1081         default:
1082                 /* the default rebase backend is `--am` */
1083                 options.type = REBASE_AM;
1084                 options.state_dir = apply_dir();
1085                 break;
1086         }
1087
1088         if (options.signoff) {
1089                 if (options.type == REBASE_PRESERVE_MERGES)
1090                         die("cannot combine '--signoff' with "
1091                             "'--preserve-merges'");
1092                 strbuf_addstr(&options.git_am_opt, " --signoff");
1093                 options.flags |= REBASE_FORCE;
1094         }
1095
1096         if (!options.root) {
1097                 if (argc < 1) {
1098                         struct branch *branch;
1099
1100                         branch = branch_get(NULL);
1101                         options.upstream_name = branch_get_upstream(branch,
1102                                                                     NULL);
1103                         if (!options.upstream_name)
1104                                 error_on_missing_default_upstream();
1105                         if (fork_point < 0)
1106                                 fork_point = 1;
1107                 } else {
1108                         options.upstream_name = argv[0];
1109                         argc--;
1110                         argv++;
1111                         if (!strcmp(options.upstream_name, "-"))
1112                                 options.upstream_name = "@{-1}";
1113                 }
1114                 options.upstream = peel_committish(options.upstream_name);
1115                 if (!options.upstream)
1116                         die(_("invalid upstream '%s'"), options.upstream_name);
1117                 options.upstream_arg = options.upstream_name;
1118         } else {
1119                 if (!options.onto_name) {
1120                         if (commit_tree("", 0, the_hash_algo->empty_tree, NULL,
1121                                         &squash_onto, NULL, NULL) < 0)
1122                                 die(_("Could not create new root commit"));
1123                         options.squash_onto = &squash_onto;
1124                         options.onto_name = squash_onto_name =
1125                                 xstrdup(oid_to_hex(&squash_onto));
1126                 }
1127                 options.upstream_name = NULL;
1128                 options.upstream = NULL;
1129                 if (argc > 1)
1130                         usage_with_options(builtin_rebase_usage,
1131                                            builtin_rebase_options);
1132                 options.upstream_arg = "--root";
1133         }
1134
1135         /* Make sure the branch to rebase onto is valid. */
1136         if (!options.onto_name)
1137                 options.onto_name = options.upstream_name;
1138         if (strstr(options.onto_name, "...")) {
1139                 if (get_oid_mb(options.onto_name, &merge_base) < 0)
1140                         die(_("'%s': need exactly one merge base"),
1141                             options.onto_name);
1142                 options.onto = lookup_commit_or_die(&merge_base,
1143                                                     options.onto_name);
1144         } else {
1145                 options.onto = peel_committish(options.onto_name);
1146                 if (!options.onto)
1147                         die(_("Does not point to a valid commit '%s'"),
1148                                 options.onto_name);
1149         }
1150
1151         /*
1152          * If the branch to rebase is given, that is the branch we will rebase
1153          * branch_name -- branch/commit being rebased, or
1154          *                HEAD (already detached)
1155          * orig_head -- commit object name of tip of the branch before rebasing
1156          * head_name -- refs/heads/<that-branch> or NULL (detached HEAD)
1157          */
1158         if (argc == 1) {
1159                 /* Is it "rebase other branchname" or "rebase other commit"? */
1160                 branch_name = argv[0];
1161                 options.switch_to = argv[0];
1162
1163                 /* Is it a local branch? */
1164                 strbuf_reset(&buf);
1165                 strbuf_addf(&buf, "refs/heads/%s", branch_name);
1166                 if (!read_ref(buf.buf, &options.orig_head))
1167                         options.head_name = xstrdup(buf.buf);
1168                 /* If not is it a valid ref (branch or commit)? */
1169                 else if (!get_oid(branch_name, &options.orig_head))
1170                         options.head_name = NULL;
1171                 else
1172                         die(_("fatal: no such branch/commit '%s'"),
1173                             branch_name);
1174         } else if (argc == 0) {
1175                 /* Do not need to switch branches, we are already on it. */
1176                 options.head_name =
1177                         xstrdup_or_null(resolve_ref_unsafe("HEAD", 0, NULL,
1178                                          &flags));
1179                 if (!options.head_name)
1180                         die(_("No such ref: %s"), "HEAD");
1181                 if (flags & REF_ISSYMREF) {
1182                         if (!skip_prefix(options.head_name,
1183                                          "refs/heads/", &branch_name))
1184                                 branch_name = options.head_name;
1185
1186                 } else {
1187                         free(options.head_name);
1188                         options.head_name = NULL;
1189                         branch_name = "HEAD";
1190                 }
1191                 if (get_oid("HEAD", &options.orig_head))
1192                         die(_("Could not resolve HEAD to a revision"));
1193         } else
1194                 BUG("unexpected number of arguments left to parse");
1195
1196         if (fork_point > 0) {
1197                 struct commit *head =
1198                         lookup_commit_reference(the_repository,
1199                                                 &options.orig_head);
1200                 options.restrict_revision =
1201                         get_fork_point(options.upstream_name, head);
1202         }
1203
1204         if (read_index(the_repository->index) < 0)
1205                 die(_("could not read index"));
1206
1207         if (options.autostash) {
1208                 struct lock_file lock_file = LOCK_INIT;
1209                 int fd;
1210
1211                 fd = hold_locked_index(&lock_file, 0);
1212                 refresh_cache(REFRESH_QUIET);
1213                 if (0 <= fd)
1214                         update_index_if_able(&the_index, &lock_file);
1215                 rollback_lock_file(&lock_file);
1216
1217                 if (has_unstaged_changes(0) || has_uncommitted_changes(0)) {
1218                         const char *autostash =
1219                                 state_dir_path("autostash", &options);
1220                         struct child_process stash = CHILD_PROCESS_INIT;
1221                         struct object_id oid;
1222                         struct commit *head =
1223                                 lookup_commit_reference(the_repository,
1224                                                         &options.orig_head);
1225
1226                         argv_array_pushl(&stash.args,
1227                                          "stash", "create", "autostash", NULL);
1228                         stash.git_cmd = 1;
1229                         stash.no_stdin = 1;
1230                         strbuf_reset(&buf);
1231                         if (capture_command(&stash, &buf, GIT_MAX_HEXSZ))
1232                                 die(_("Cannot autostash"));
1233                         strbuf_trim_trailing_newline(&buf);
1234                         if (get_oid(buf.buf, &oid))
1235                                 die(_("Unexpected stash response: '%s'"),
1236                                     buf.buf);
1237                         strbuf_reset(&buf);
1238                         strbuf_add_unique_abbrev(&buf, &oid, DEFAULT_ABBREV);
1239
1240                         if (safe_create_leading_directories_const(autostash))
1241                                 die(_("Could not create directory for '%s'"),
1242                                     options.state_dir);
1243                         write_file(autostash, "%s", buf.buf);
1244                         printf(_("Created autostash: %s\n"), buf.buf);
1245                         if (reset_head(&head->object.oid, "reset --hard",
1246                                        NULL, 0, NULL, NULL) < 0)
1247                                 die(_("could not reset --hard"));
1248                         printf(_("HEAD is now at %s"),
1249                                find_unique_abbrev(&head->object.oid,
1250                                                   DEFAULT_ABBREV));
1251                         strbuf_reset(&buf);
1252                         pp_commit_easy(CMIT_FMT_ONELINE, head, &buf);
1253                         if (buf.len > 0)
1254                                 printf(" %s", buf.buf);
1255                         putchar('\n');
1256
1257                         if (discard_index(the_repository->index) < 0 ||
1258                                 read_index(the_repository->index) < 0)
1259                                 die(_("could not read index"));
1260                 }
1261         }
1262
1263         if (require_clean_work_tree("rebase",
1264                                     _("Please commit or stash them."), 1, 1)) {
1265                 ret = 1;
1266                 goto cleanup;
1267         }
1268
1269         /*
1270          * Now we are rebasing commits upstream..orig_head (or with --root,
1271          * everything leading up to orig_head) on top of onto.
1272          */
1273
1274         /*
1275          * Check if we are already based on onto with linear history,
1276          * but this should be done only when upstream and onto are the same
1277          * and if this is not an interactive rebase.
1278          */
1279         if (can_fast_forward(options.onto, &options.orig_head, &merge_base) &&
1280             !is_interactive(&options) && !options.restrict_revision &&
1281             options.upstream &&
1282             !oidcmp(&options.upstream->object.oid, &options.onto->object.oid)) {
1283                 int flag;
1284
1285                 if (!(options.flags & REBASE_FORCE)) {
1286                         /* Lazily switch to the target branch if needed... */
1287                         if (options.switch_to) {
1288                                 struct object_id oid;
1289
1290                                 if (get_oid(options.switch_to, &oid) < 0) {
1291                                         ret = !!error(_("could not parse '%s'"),
1292                                                       options.switch_to);
1293                                         goto cleanup;
1294                                 }
1295
1296                                 strbuf_reset(&buf);
1297                                 strbuf_addf(&buf, "rebase: checkout %s",
1298                                             options.switch_to);
1299                                 if (reset_head(&oid, "checkout",
1300                                                options.head_name, 0,
1301                                                NULL, NULL) < 0) {
1302                                         ret = !!error(_("could not switch to "
1303                                                         "%s"),
1304                                                       options.switch_to);
1305                                         goto cleanup;
1306                                 }
1307                         }
1308
1309                         if (!(options.flags & REBASE_NO_QUIET))
1310                                 ; /* be quiet */
1311                         else if (!strcmp(branch_name, "HEAD") &&
1312                                  resolve_ref_unsafe("HEAD", 0, NULL, &flag))
1313                                 puts(_("HEAD is up to date."));
1314                         else
1315                                 printf(_("Current branch %s is up to date.\n"),
1316                                        branch_name);
1317                         ret = !!finish_rebase(&options);
1318                         goto cleanup;
1319                 } else if (!(options.flags & REBASE_NO_QUIET))
1320                         ; /* be quiet */
1321                 else if (!strcmp(branch_name, "HEAD") &&
1322                          resolve_ref_unsafe("HEAD", 0, NULL, &flag))
1323                         puts(_("HEAD is up to date, rebase forced."));
1324                 else
1325                         printf(_("Current branch %s is up to date, rebase "
1326                                  "forced.\n"), branch_name);
1327         }
1328
1329         /* If a hook exists, give it a chance to interrupt*/
1330         if (!ok_to_skip_pre_rebase &&
1331             run_hook_le(NULL, "pre-rebase", options.upstream_arg,
1332                         argc ? argv[0] : NULL, NULL))
1333                 die(_("The pre-rebase hook refused to rebase."));
1334
1335         if (options.flags & REBASE_DIFFSTAT) {
1336                 struct diff_options opts;
1337
1338                 if (options.flags & REBASE_VERBOSE)
1339                         printf(_("Changes from %s to %s:\n"),
1340                                 oid_to_hex(&merge_base),
1341                                 oid_to_hex(&options.onto->object.oid));
1342
1343                 /* We want color (if set), but no pager */
1344                 diff_setup(&opts);
1345                 opts.stat_width = -1; /* use full terminal width */
1346                 opts.stat_graph_width = -1; /* respect statGraphWidth config */
1347                 opts.output_format |=
1348                         DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
1349                 opts.detect_rename = DIFF_DETECT_RENAME;
1350                 diff_setup_done(&opts);
1351                 diff_tree_oid(&merge_base, &options.onto->object.oid,
1352                               "", &opts);
1353                 diffcore_std(&opts);
1354                 diff_flush(&opts);
1355         }
1356
1357         if (is_interactive(&options))
1358                 goto run_rebase;
1359
1360         /* Detach HEAD and reset the tree */
1361         if (options.flags & REBASE_NO_QUIET)
1362                 printf(_("First, rewinding head to replay your work on top of "
1363                          "it...\n"));
1364
1365         strbuf_addf(&msg, "rebase: checkout %s", options.onto_name);
1366         if (reset_head(&options.onto->object.oid, "checkout", NULL, 1,
1367             NULL, msg.buf))
1368                 die(_("Could not detach HEAD"));
1369         strbuf_release(&msg);
1370
1371         strbuf_addf(&revisions, "%s..%s",
1372                     options.root ? oid_to_hex(&options.onto->object.oid) :
1373                     (options.restrict_revision ?
1374                      oid_to_hex(&options.restrict_revision->object.oid) :
1375                      oid_to_hex(&options.upstream->object.oid)),
1376                     oid_to_hex(&options.orig_head));
1377
1378         options.revisions = revisions.buf;
1379
1380 run_rebase:
1381         ret = !!run_specific_rebase(&options);
1382
1383 cleanup:
1384         strbuf_release(&revisions);
1385         free(options.head_name);
1386         free(options.gpg_sign_opt);
1387         free(options.cmd);
1388         free(squash_onto_name);
1389         return ret;
1390 }