builtin/rebase.c

   1 /*
   2  * "git rebase" builtin command
   3  *
   4  * Copyright (c) 2018 Pratik Karki
   5  */
   6
   7 #define USE_THE_INDEX_VARIABLE
   8 #include "builtin.h"
   9 #include "abspath.h"
  10 #include "environment.h"
  11 #include "gettext.h"
  12 #include "hex.h"
  13 #include "run-command.h"
  14 #include "exec-cmd.h"
  15 #include "strvec.h"
  16 #include "dir.h"
  17 #include "packfile.h"
  18 #include "refs.h"
  19 #include "quote.h"
  20 #include "config.h"
  21 #include "cache-tree.h"
  22 #include "unpack-trees.h"
  23 #include "lockfile.h"
  24 #include "object-file.h"
  25 #include "object-name.h"
  26 #include "parse-options.h"
  27 #include "path.h"
  28 #include "commit.h"
  29 #include "diff.h"
  30 #include "wt-status.h"
  31 #include "revision.h"
  32 #include "commit-reach.h"
  33 #include "rerere.h"
  34 #include "branch.h"
  35 #include "sequencer.h"
  36 #include "rebase-interactive.h"
  37 #include "reset.h"
  38 #include "trace2.h"
  39 #include "hook.h"
  40
  41 static char const * const builtin_rebase_usage[] = {
  42         N_("git rebase [-i] [options] [--exec <cmd>] "
  43                 "[--onto <newbase> | --keep-base] [<upstream> [<branch>]]"),
  44         N_("git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] "
  45                 "--root [<branch>]"),
  46         "git rebase --continue | --abort | --skip | --edit-todo",
  47         NULL
  48 };
  49
  50 static GIT_PATH_FUNC(path_squash_onto, "rebase-merge/squash-onto")
  51 static GIT_PATH_FUNC(path_interactive, "rebase-merge/interactive")
  52 static GIT_PATH_FUNC(apply_dir, "rebase-apply")
  53 static GIT_PATH_FUNC(merge_dir, "rebase-merge")
  54
  55 enum rebase_type {
  56         REBASE_UNSPECIFIED = -1,
  57         REBASE_APPLY,
  58         REBASE_MERGE
  59 };
  60
  61 enum empty_type {
  62         EMPTY_UNSPECIFIED = -1,
  63         EMPTY_DROP,
  64         EMPTY_KEEP,
  65         EMPTY_ASK
  66 };
  67
  68 enum action {
  69         ACTION_NONE = 0,
  70         ACTION_CONTINUE,
  71         ACTION_SKIP,
  72         ACTION_ABORT,
  73         ACTION_QUIT,
  74         ACTION_EDIT_TODO,
  75         ACTION_SHOW_CURRENT_PATCH
  76 };
  77
  78 static const char *action_names[] = {
  79         "undefined",
  80         "continue",
  81         "skip",
  82         "abort",
  83         "quit",
  84         "edit_todo",
  85         "show_current_patch"
  86 };
  87
  88 struct rebase_options {
  89         enum rebase_type type;
  90         enum empty_type empty;
  91         const char *default_backend;
  92         const char *state_dir;
  93         struct commit *upstream;
  94         const char *upstream_name;
  95         const char *upstream_arg;
  96         char *head_name;
  97         struct commit *orig_head;
  98         struct commit *onto;
  99         const char *onto_name;
 100         const char *revisions;
 101         const char *switch_to;
 102         int root, root_with_onto;
 103         struct object_id *squash_onto;
 104         struct commit *restrict_revision;
 105         int dont_finish_rebase;
 106         enum {
 107                 REBASE_NO_QUIET = 1<<0,
 108                 REBASE_VERBOSE = 1<<1,
 109                 REBASE_DIFFSTAT = 1<<2,
 110                 REBASE_FORCE = 1<<3,
 111                 REBASE_INTERACTIVE_EXPLICIT = 1<<4,
 112         } flags;
 113         struct strvec git_am_opts;
 114         enum action action;
 115         char *reflog_action;
 116         int signoff;
 117         int allow_rerere_autoupdate;
 118         int keep_empty;
 119         int autosquash;
 120         char *gpg_sign_opt;
 121         int autostash;
 122         int committer_date_is_author_date;
 123         int ignore_date;
 124         struct string_list exec;
 125         int allow_empty_message;
 126         int rebase_merges, rebase_cousins;
 127         char *strategy;
 128         struct string_list strategy_opts;
 129         struct strbuf git_format_patch_opt;
 130         int reschedule_failed_exec;
 131         int reapply_cherry_picks;
 132         int fork_point;
 133         int update_refs;
 134         int config_autosquash;
 135         int config_rebase_merges;
 136         int config_update_refs;
 137 };
 138
 139 #define REBASE_OPTIONS_INIT {                           \
 140                 .type = REBASE_UNSPECIFIED,             \
 141                 .empty = EMPTY_UNSPECIFIED,             \
 142                 .keep_empty = 1,                        \
 143                 .default_backend = "merge",             \
 144                 .flags = REBASE_NO_QUIET,               \
 145                 .git_am_opts = STRVEC_INIT,             \
 146                 .exec = STRING_LIST_INIT_NODUP,         \
 147                 .git_format_patch_opt = STRBUF_INIT,    \
 148                 .fork_point = -1,                       \
 149                 .reapply_cherry_picks = -1,             \
 150                 .allow_empty_message = 1,               \
 151                 .autosquash = -1,                       \
 152                 .config_autosquash = -1,                \
 153                 .rebase_merges = -1,                    \
 154                 .config_rebase_merges = -1,             \
 155                 .update_refs = -1,                      \
 156                 .config_update_refs = -1,               \
 157                 .strategy_opts = STRING_LIST_INIT_NODUP,\
 158         }
 159
 160 static struct replay_opts get_replay_opts(const struct rebase_options *opts)
 161 {
 162         struct replay_opts replay = REPLAY_OPTS_INIT;
 163
 164         replay.action = REPLAY_INTERACTIVE_REBASE;
 165         replay.strategy = NULL;
 166         sequencer_init_config(&replay);
 167
 168         replay.signoff = opts->signoff;
 169         replay.allow_ff = !(opts->flags & REBASE_FORCE);
 170         if (opts->allow_rerere_autoupdate)
 171                 replay.allow_rerere_auto = opts->allow_rerere_autoupdate;
 172         replay.allow_empty = 1;
 173         replay.allow_empty_message = opts->allow_empty_message;
 174         replay.drop_redundant_commits = (opts->empty == EMPTY_DROP);
 175         replay.keep_redundant_commits = (opts->empty == EMPTY_KEEP);
 176         replay.quiet = !(opts->flags & REBASE_NO_QUIET);
 177         replay.verbose = opts->flags & REBASE_VERBOSE;
 178         replay.reschedule_failed_exec = opts->reschedule_failed_exec;
 179         replay.committer_date_is_author_date =
 180                                         opts->committer_date_is_author_date;
 181         replay.ignore_date = opts->ignore_date;
 182         replay.gpg_sign = xstrdup_or_null(opts->gpg_sign_opt);
 183         replay.reflog_action = xstrdup(opts->reflog_action);
 184         if (opts->strategy)
 185                 replay.strategy = xstrdup_or_null(opts->strategy);
 186         else if (!replay.strategy && replay.default_strategy) {
 187                 replay.strategy = replay.default_strategy;
 188                 replay.default_strategy = NULL;
 189         }
 190
 191         for (size_t i = 0; i < opts->strategy_opts.nr; i++)
 192                 strvec_push(&replay.xopts, opts->strategy_opts.items[i].string);
 193
 194         if (opts->squash_onto) {
 195                 oidcpy(&replay.squash_onto, opts->squash_onto);
 196                 replay.have_squash_onto = 1;
 197         }
 198
 199         return replay;
 200 }
 201
 202 static int edit_todo_file(unsigned flags)
 203 {
 204         const char *todo_file = rebase_path_todo();
 205         struct todo_list todo_list = TODO_LIST_INIT,
 206                 new_todo = TODO_LIST_INIT;
 207         int res = 0;
 208
 209         if (strbuf_read_file(&todo_list.buf, todo_file, 0) < 0)
 210                 return error_errno(_("could not read '%s'."), todo_file);
 211
 212         strbuf_stripspace(&todo_list.buf, comment_line_char);
 213         res = edit_todo_list(the_repository, &todo_list, &new_todo, NULL, NULL, flags);
 214         if (!res && todo_list_write_to_file(the_repository, &new_todo, todo_file,
 215                                             NULL, NULL, -1, flags & ~(TODO_LIST_SHORTEN_IDS)))
 216                 res = error_errno(_("could not write '%s'"), todo_file);
 217
 218         todo_list_release(&todo_list);
 219         todo_list_release(&new_todo);
 220
 221         return res;
 222 }
 223
 224 static int get_revision_ranges(struct commit *upstream, struct commit *onto,
 225                                struct object_id *orig_head, char **revisions,
 226                                char **shortrevisions)
 227 {
 228         struct commit *base_rev = upstream ? upstream : onto;
 229         const char *shorthead;
 230
 231         *revisions = xstrfmt("%s...%s", oid_to_hex(&base_rev->object.oid),
 232                              oid_to_hex(orig_head));
 233
 234         shorthead = repo_find_unique_abbrev(the_repository, orig_head,
 235                                             DEFAULT_ABBREV);
 236
 237         if (upstream) {
 238                 const char *shortrev;
 239
 240                 shortrev = repo_find_unique_abbrev(the_repository,
 241                                                    &base_rev->object.oid,
 242                                                    DEFAULT_ABBREV);
 243
 244                 *shortrevisions = xstrfmt("%s..%s", shortrev, shorthead);
 245         } else
 246                 *shortrevisions = xstrdup(shorthead);
 247
 248         return 0;
 249 }
 250
 251 static int init_basic_state(struct replay_opts *opts, const char *head_name,
 252                             struct commit *onto,
 253                             const struct object_id *orig_head)
 254 {
 255         FILE *interactive;
 256
 257         if (!is_directory(merge_dir()) && mkdir_in_gitdir(merge_dir()))
 258                 return error_errno(_("could not create temporary %s"), merge_dir());
 259
 260         delete_reflog("REBASE_HEAD");
 261
 262         interactive = fopen(path_interactive(), "w");
 263         if (!interactive)
 264                 return error_errno(_("could not mark as interactive"));
 265         fclose(interactive);
 266
 267         return write_basic_state(opts, head_name, onto, orig_head);
 268 }
 269
 270 static int do_interactive_rebase(struct rebase_options *opts, unsigned flags)
 271 {
 272         int ret = -1;
 273         char *revisions = NULL, *shortrevisions = NULL;
 274         struct strvec make_script_args = STRVEC_INIT;
 275         struct todo_list todo_list = TODO_LIST_INIT;
 276         struct replay_opts replay = get_replay_opts(opts);
 277
 278         if (get_revision_ranges(opts->upstream, opts->onto, &opts->orig_head->object.oid,
 279                                 &revisions, &shortrevisions))
 280                 goto cleanup;
 281
 282         if (init_basic_state(&replay,
 283                              opts->head_name ? opts->head_name : "detached HEAD",
 284                              opts->onto, &opts->orig_head->object.oid))
 285                 goto cleanup;
 286
 287         if (!opts->upstream && opts->squash_onto)
 288                 write_file(path_squash_onto(), "%s\n",
 289                            oid_to_hex(opts->squash_onto));
 290
 291         strvec_pushl(&make_script_args, "", revisions, NULL);
 292         if (opts->restrict_revision)
 293                 strvec_pushf(&make_script_args, "^%s",
 294                              oid_to_hex(&opts->restrict_revision->object.oid));
 295
 296         ret = sequencer_make_script(the_repository, &todo_list.buf,
 297                                     make_script_args.nr, make_script_args.v,
 298                                     flags);
 299
 300         if (ret)
 301                 error(_("could not generate todo list"));
 302         else {
 303                 discard_index(&the_index);
 304                 if (todo_list_parse_insn_buffer(the_repository, todo_list.buf.buf,
 305                                                 &todo_list))
 306                         BUG("unusable todo list");
 307
 308                 ret = complete_action(the_repository, &replay, flags,
 309                         shortrevisions, opts->onto_name, opts->onto,
 310                         &opts->orig_head->object.oid, &opts->exec,
 311                         opts->autosquash, opts->update_refs, &todo_list);
 312         }
 313
 314 cleanup:
 315         replay_opts_release(&replay);
 316         free(revisions);
 317         free(shortrevisions);
 318         todo_list_release(&todo_list);
 319         strvec_clear(&make_script_args);
 320
 321         return ret;
 322 }
 323
 324 static int run_sequencer_rebase(struct rebase_options *opts)
 325 {
 326         unsigned flags = 0;
 327         int abbreviate_commands = 0, ret = 0;
 328
 329         git_config_get_bool("rebase.abbreviatecommands", &abbreviate_commands);
 330
 331         flags |= opts->keep_empty ? TODO_LIST_KEEP_EMPTY : 0;
 332         flags |= abbreviate_commands ? TODO_LIST_ABBREVIATE_CMDS : 0;
 333         flags |= opts->rebase_merges ? TODO_LIST_REBASE_MERGES : 0;
 334         flags |= opts->rebase_cousins > 0 ? TODO_LIST_REBASE_COUSINS : 0;
 335         flags |= opts->root_with_onto ? TODO_LIST_ROOT_WITH_ONTO : 0;
 336         flags |= opts->reapply_cherry_picks ? TODO_LIST_REAPPLY_CHERRY_PICKS : 0;
 337         flags |= opts->flags & REBASE_NO_QUIET ? TODO_LIST_WARN_SKIPPED_CHERRY_PICKS : 0;
 338
 339         switch (opts->action) {
 340         case ACTION_NONE: {
 341                 if (!opts->onto && !opts->upstream)
 342                         die(_("a base commit must be provided with --upstream or --onto"));
 343
 344                 ret = do_interactive_rebase(opts, flags);
 345                 break;
 346         }
 347         case ACTION_SKIP: {
 348                 struct string_list merge_rr = STRING_LIST_INIT_DUP;
 349
 350                 rerere_clear(the_repository, &merge_rr);
 351         }
 352                 /* fallthrough */
 353         case ACTION_CONTINUE: {
 354                 struct replay_opts replay_opts = get_replay_opts(opts);
 355
 356                 ret = sequencer_continue(the_repository, &replay_opts);
 357                 replay_opts_release(&replay_opts);
 358                 break;
 359         }
 360         case ACTION_EDIT_TODO:
 361                 ret = edit_todo_file(flags);
 362                 break;
 363         case ACTION_SHOW_CURRENT_PATCH: {
 364                 struct child_process cmd = CHILD_PROCESS_INIT;
 365
 366                 cmd.git_cmd = 1;
 367                 strvec_pushl(&cmd.args, "show", "REBASE_HEAD", "--", NULL);
 368                 ret = run_command(&cmd);
 369
 370                 break;
 371         }
 372         default:
 373                 BUG("invalid command '%d'", opts->action);
 374         }
 375
 376         return ret;
 377 }
 378
 379 static void imply_merge(struct rebase_options *opts, const char *option);
 380 static int parse_opt_keep_empty(const struct option *opt, const char *arg,
 381                                 int unset)
 382 {
 383         struct rebase_options *opts = opt->value;
 384
 385         BUG_ON_OPT_ARG(arg);
 386
 387         imply_merge(opts, unset ? "--no-keep-empty" : "--keep-empty");
 388         opts->keep_empty = !unset;
 389         opts->type = REBASE_MERGE;
 390         return 0;
 391 }
 392
 393 static int is_merge(struct rebase_options *opts)
 394 {
 395         return opts->type == REBASE_MERGE;
 396 }
 397
 398 static void imply_merge(struct rebase_options *opts, const char *option)
 399 {
 400         switch (opts->type) {
 401         case REBASE_APPLY:
 402                 die(_("%s requires the merge backend"), option);
 403                 break;
 404         case REBASE_MERGE:
 405                 break;
 406         default:
 407                 opts->type = REBASE_MERGE; /* implied */
 408                 break;
 409         }
 410 }
 411
 412 /* Returns the filename prefixed by the state_dir */
 413 static const char *state_dir_path(const char *filename, struct rebase_options *opts)
 414 {
 415         static struct strbuf path = STRBUF_INIT;
 416         static size_t prefix_len;
 417
 418         if (!prefix_len) {
 419                 strbuf_addf(&path, "%s/", opts->state_dir);
 420                 prefix_len = path.len;
 421         }
 422
 423         strbuf_setlen(&path, prefix_len);
 424         strbuf_addstr(&path, filename);
 425         return path.buf;
 426 }
 427
 428 /* Initialize the rebase options from the state directory. */
 429 static int read_basic_state(struct rebase_options *opts)
 430 {
 431         struct strbuf head_name = STRBUF_INIT;
 432         struct strbuf buf = STRBUF_INIT;
 433         struct object_id oid;
 434
 435         if (!read_oneliner(&head_name, state_dir_path("head-name", opts),
 436                            READ_ONELINER_WARN_MISSING) ||
 437             !read_oneliner(&buf, state_dir_path("onto", opts),
 438                            READ_ONELINER_WARN_MISSING))
 439                 return -1;
 440         opts->head_name = starts_with(head_name.buf, "refs/") ?
 441                 xstrdup(head_name.buf) : NULL;
 442         strbuf_release(&head_name);
 443         if (get_oid_hex(buf.buf, &oid) ||
 444             !(opts->onto = lookup_commit_object(the_repository, &oid)))
 445                 return error(_("invalid onto: '%s'"), buf.buf);
 446
 447         /*
 448          * We always write to orig-head, but interactive rebase used to write to
 449          * head. Fall back to reading from head to cover for the case that the
 450          * user upgraded git with an ongoing interactive rebase.
 451          */
 452         strbuf_reset(&buf);
 453         if (file_exists(state_dir_path("orig-head", opts))) {
 454                 if (!read_oneliner(&buf, state_dir_path("orig-head", opts),
 455                                    READ_ONELINER_WARN_MISSING))
 456                         return -1;
 457         } else if (!read_oneliner(&buf, state_dir_path("head", opts),
 458                                   READ_ONELINER_WARN_MISSING))
 459                 return -1;
 460         if (get_oid_hex(buf.buf, &oid) ||
 461             !(opts->orig_head = lookup_commit_object(the_repository, &oid)))
 462                 return error(_("invalid orig-head: '%s'"), buf.buf);
 463
 464         if (file_exists(state_dir_path("quiet", opts)))
 465                 opts->flags &= ~REBASE_NO_QUIET;
 466         else
 467                 opts->flags |= REBASE_NO_QUIET;
 468
 469         if (file_exists(state_dir_path("verbose", opts)))
 470                 opts->flags |= REBASE_VERBOSE;
 471
 472         if (file_exists(state_dir_path("signoff", opts))) {
 473                 opts->signoff = 1;
 474                 opts->flags |= REBASE_FORCE;
 475         }
 476
 477         if (file_exists(state_dir_path("allow_rerere_autoupdate", opts))) {
 478                 strbuf_reset(&buf);
 479                 if (!read_oneliner(&buf, state_dir_path("allow_rerere_autoupdate", opts),
 480                                    READ_ONELINER_WARN_MISSING))
 481                         return -1;
 482                 if (!strcmp(buf.buf, "--rerere-autoupdate"))
 483                         opts->allow_rerere_autoupdate = RERERE_AUTOUPDATE;
 484                 else if (!strcmp(buf.buf, "--no-rerere-autoupdate"))
 485                         opts->allow_rerere_autoupdate = RERERE_NOAUTOUPDATE;
 486                 else
 487                         warning(_("ignoring invalid allow_rerere_autoupdate: "
 488                                   "'%s'"), buf.buf);
 489         }
 490
 491         if (file_exists(state_dir_path("gpg_sign_opt", opts))) {
 492                 strbuf_reset(&buf);
 493                 if (!read_oneliner(&buf, state_dir_path("gpg_sign_opt", opts),
 494                                    READ_ONELINER_WARN_MISSING))
 495                         return -1;
 496                 free(opts->gpg_sign_opt);
 497                 opts->gpg_sign_opt = xstrdup(buf.buf);
 498         }
 499
 500         strbuf_release(&buf);
 501
 502         return 0;
 503 }
 504
 505 static int rebase_write_basic_state(struct rebase_options *opts)
 506 {
 507         write_file(state_dir_path("head-name", opts), "%s",
 508                    opts->head_name ? opts->head_name : "detached HEAD");
 509         write_file(state_dir_path("onto", opts), "%s",
 510                    opts->onto ? oid_to_hex(&opts->onto->object.oid) : "");
 511         write_file(state_dir_path("orig-head", opts), "%s",
 512                    oid_to_hex(&opts->orig_head->object.oid));
 513         if (!(opts->flags & REBASE_NO_QUIET))
 514                 write_file(state_dir_path("quiet", opts), "%s", "");
 515         if (opts->flags & REBASE_VERBOSE)
 516                 write_file(state_dir_path("verbose", opts), "%s", "");
 517         if (opts->allow_rerere_autoupdate > 0)
 518                 write_file(state_dir_path("allow_rerere_autoupdate", opts),
 519                            "-%s-rerere-autoupdate",
 520                            opts->allow_rerere_autoupdate == RERERE_AUTOUPDATE ?
 521                                 "" : "-no");
 522         if (opts->gpg_sign_opt)
 523                 write_file(state_dir_path("gpg_sign_opt", opts), "%s",
 524                            opts->gpg_sign_opt);
 525         if (opts->signoff)
 526                 write_file(state_dir_path("signoff", opts), "--signoff");
 527
 528         return 0;
 529 }
 530
 531 static int finish_rebase(struct rebase_options *opts)
 532 {
 533         struct strbuf dir = STRBUF_INIT;
 534         int ret = 0;
 535
 536         delete_ref(NULL, "REBASE_HEAD", NULL, REF_NO_DEREF);
 537         unlink(git_path_auto_merge(the_repository));
 538         apply_autostash(state_dir_path("autostash", opts));
 539         /*
 540          * We ignore errors in 'git maintenance run --auto', since the
 541          * user should see them.
 542          */
 543         run_auto_maintenance(!(opts->flags & (REBASE_NO_QUIET|REBASE_VERBOSE)));
 544         if (opts->type == REBASE_MERGE) {
 545                 struct replay_opts replay = REPLAY_OPTS_INIT;
 546
 547                 replay.action = REPLAY_INTERACTIVE_REBASE;
 548                 ret = sequencer_remove_state(&replay);
 549                 replay_opts_release(&replay);
 550         } else {
 551                 strbuf_addstr(&dir, opts->state_dir);
 552                 if (remove_dir_recursively(&dir, 0))
 553                         ret = error(_("could not remove '%s'"),
 554                                     opts->state_dir);
 555                 strbuf_release(&dir);
 556         }
 557
 558         return ret;
 559 }
 560
 561 static int move_to_original_branch(struct rebase_options *opts)
 562 {
 563         struct strbuf branch_reflog = STRBUF_INIT, head_reflog = STRBUF_INIT;
 564         struct reset_head_opts ropts = { 0 };
 565         int ret;
 566
 567         if (!opts->head_name)
 568                 return 0; /* nothing to move back to */
 569
 570         if (!opts->onto)
 571                 BUG("move_to_original_branch without onto");
 572
 573         strbuf_addf(&branch_reflog, "%s (finish): %s onto %s",
 574                     opts->reflog_action,
 575                     opts->head_name, oid_to_hex(&opts->onto->object.oid));
 576         strbuf_addf(&head_reflog, "%s (finish): returning to %s",
 577                     opts->reflog_action, opts->head_name);
 578         ropts.branch = opts->head_name;
 579         ropts.flags = RESET_HEAD_REFS_ONLY;
 580         ropts.branch_msg = branch_reflog.buf;
 581         ropts.head_msg = head_reflog.buf;
 582         ret = reset_head(the_repository, &ropts);
 583
 584         strbuf_release(&branch_reflog);
 585         strbuf_release(&head_reflog);
 586         return ret;
 587 }
 588
 589 static const char *resolvemsg =
 590 N_("Resolve all conflicts manually, mark them as resolved with\n"
 591 "\"git add/rm <conflicted_files>\", then run \"git rebase --continue\".\n"
 592 "You can instead skip this commit: run \"git rebase --skip\".\n"
 593 "To abort and get back to the state before \"git rebase\", run "
 594 "\"git rebase --abort\".");
 595
 596 static int run_am(struct rebase_options *opts)
 597 {
 598         struct child_process am = CHILD_PROCESS_INIT;
 599         struct child_process format_patch = CHILD_PROCESS_INIT;
 600         struct strbuf revisions = STRBUF_INIT;
 601         int status;
 602         char *rebased_patches;
 603
 604         am.git_cmd = 1;
 605         strvec_push(&am.args, "am");
 606         strvec_pushf(&am.env, GIT_REFLOG_ACTION_ENVIRONMENT "=%s (pick)",
 607                      opts->reflog_action);
 608         if (opts->action == ACTION_CONTINUE) {
 609                 strvec_push(&am.args, "--resolved");
 610                 strvec_pushf(&am.args, "--resolvemsg=%s", resolvemsg);
 611                 if (opts->gpg_sign_opt)
 612                         strvec_push(&am.args, opts->gpg_sign_opt);
 613                 status = run_command(&am);
 614                 if (status)
 615                         return status;
 616
 617                 return move_to_original_branch(opts);
 618         }
 619         if (opts->action == ACTION_SKIP) {
 620                 strvec_push(&am.args, "--skip");
 621                 strvec_pushf(&am.args, "--resolvemsg=%s", resolvemsg);
 622                 status = run_command(&am);
 623                 if (status)
 624                         return status;
 625
 626                 return move_to_original_branch(opts);
 627         }
 628         if (opts->action == ACTION_SHOW_CURRENT_PATCH) {
 629                 strvec_push(&am.args, "--show-current-patch");
 630                 return run_command(&am);
 631         }
 632
 633         strbuf_addf(&revisions, "%s...%s",
 634                     oid_to_hex(opts->root ?
 635                                /* this is now equivalent to !opts->upstream */
 636                                &opts->onto->object.oid :
 637                                &opts->upstream->object.oid),
 638                     oid_to_hex(&opts->orig_head->object.oid));
 639
 640         rebased_patches = xstrdup(git_path("rebased-patches"));
 641         format_patch.out = open(rebased_patches,
 642                                 O_WRONLY | O_CREAT | O_TRUNC, 0666);
 643         if (format_patch.out < 0) {
 644                 status = error_errno(_("could not open '%s' for writing"),
 645                                      rebased_patches);
 646                 free(rebased_patches);
 647                 strvec_clear(&am.args);
 648                 return status;
 649         }
 650
 651         format_patch.git_cmd = 1;
 652         strvec_pushl(&format_patch.args, "format-patch", "-k", "--stdout",
 653                      "--full-index", "--cherry-pick", "--right-only",
 654                      "--default-prefix", "--no-renames",
 655                      "--no-cover-letter", "--pretty=mboxrd", "--topo-order",
 656                      "--no-base", NULL);
 657         if (opts->git_format_patch_opt.len)
 658                 strvec_split(&format_patch.args,
 659                              opts->git_format_patch_opt.buf);
 660         strvec_push(&format_patch.args, revisions.buf);
 661         if (opts->restrict_revision)
 662                 strvec_pushf(&format_patch.args, "^%s",
 663                              oid_to_hex(&opts->restrict_revision->object.oid));
 664
 665         status = run_command(&format_patch);
 666         if (status) {
 667                 struct reset_head_opts ropts = { 0 };
 668                 unlink(rebased_patches);
 669                 free(rebased_patches);
 670                 strvec_clear(&am.args);
 671
 672                 ropts.oid = &opts->orig_head->object.oid;
 673                 ropts.branch = opts->head_name;
 674                 ropts.default_reflog_action = opts->reflog_action;
 675                 reset_head(the_repository, &ropts);
 676                 error(_("\ngit encountered an error while preparing the "
 677                         "patches to replay\n"
 678                         "these revisions:\n"
 679                         "\n    %s\n\n"
 680                         "As a result, git cannot rebase them."),
 681                       opts->revisions);
 682
 683                 strbuf_release(&revisions);
 684                 return status;
 685         }
 686         strbuf_release(&revisions);
 687
 688         am.in = open(rebased_patches, O_RDONLY);
 689         if (am.in < 0) {
 690                 status = error_errno(_("could not open '%s' for reading"),
 691                                      rebased_patches);
 692                 free(rebased_patches);
 693                 strvec_clear(&am.args);
 694                 return status;
 695         }
 696
 697         strvec_pushv(&am.args, opts->git_am_opts.v);
 698         strvec_push(&am.args, "--rebasing");
 699         strvec_pushf(&am.args, "--resolvemsg=%s", resolvemsg);
 700         strvec_push(&am.args, "--patch-format=mboxrd");
 701         if (opts->allow_rerere_autoupdate == RERERE_AUTOUPDATE)
 702                 strvec_push(&am.args, "--rerere-autoupdate");
 703         else if (opts->allow_rerere_autoupdate == RERERE_NOAUTOUPDATE)
 704                 strvec_push(&am.args, "--no-rerere-autoupdate");
 705         if (opts->gpg_sign_opt)
 706                 strvec_push(&am.args, opts->gpg_sign_opt);
 707         status = run_command(&am);
 708         unlink(rebased_patches);
 709         free(rebased_patches);
 710
 711         if (!status) {
 712                 return move_to_original_branch(opts);
 713         }
 714
 715         if (is_directory(opts->state_dir))
 716                 rebase_write_basic_state(opts);
 717
 718         return status;
 719 }
 720
 721 static int run_specific_rebase(struct rebase_options *opts)
 722 {
 723         int status;
 724
 725         if (opts->type == REBASE_MERGE) {
 726                 /* Run sequencer-based rebase */
 727                 setenv("GIT_CHERRY_PICK_HELP", resolvemsg, 1);
 728                 if (!(opts->flags & REBASE_INTERACTIVE_EXPLICIT)) {
 729                         setenv("GIT_SEQUENCE_EDITOR", ":", 1);
 730                         opts->autosquash = 0;
 731                 }
 732                 if (opts->gpg_sign_opt) {
 733                         /* remove the leading "-S" */
 734                         char *tmp = xstrdup(opts->gpg_sign_opt + 2);
 735                         free(opts->gpg_sign_opt);
 736                         opts->gpg_sign_opt = tmp;
 737                 }
 738
 739                 status = run_sequencer_rebase(opts);
 740         } else if (opts->type == REBASE_APPLY)
 741                 status = run_am(opts);
 742         else
 743                 BUG("Unhandled rebase type %d", opts->type);
 744
 745         if (opts->dont_finish_rebase)
 746                 ; /* do nothing */
 747         else if (opts->type == REBASE_MERGE)
 748                 ; /* merge backend cleans up after itself */
 749         else if (status == 0) {
 750                 if (!file_exists(state_dir_path("stopped-sha", opts)))
 751                         finish_rebase(opts);
 752         } else if (status == 2) {
 753                 struct strbuf dir = STRBUF_INIT;
 754
 755                 apply_autostash(state_dir_path("autostash", opts));
 756                 strbuf_addstr(&dir, opts->state_dir);
 757                 remove_dir_recursively(&dir, 0);
 758                 strbuf_release(&dir);
 759                 die("Nothing to do");
 760         }
 761
 762         return status ? -1 : 0;
 763 }
 764
 765 static void parse_rebase_merges_value(struct rebase_options *options, const char *value)
 766 {
 767         if (!strcmp("no-rebase-cousins", value))
 768                 options->rebase_cousins = 0;
 769         else if (!strcmp("rebase-cousins", value))
 770                 options->rebase_cousins = 1;
 771         else
 772                 die(_("Unknown rebase-merges mode: %s"), value);
 773 }
 774
 775 static int rebase_config(const char *var, const char *value,
 776                          const struct config_context *ctx, void *data)
 777 {
 778         struct rebase_options *opts = data;
 779
 780         if (!strcmp(var, "rebase.stat")) {
 781                 if (git_config_bool(var, value))
 782                         opts->flags |= REBASE_DIFFSTAT;
 783                 else
 784                         opts->flags &= ~REBASE_DIFFSTAT;
 785                 return 0;
 786         }
 787
 788         if (!strcmp(var, "rebase.autosquash")) {
 789                 opts->config_autosquash = git_config_bool(var, value);
 790                 return 0;
 791         }
 792
 793         if (!strcmp(var, "commit.gpgsign")) {
 794                 free(opts->gpg_sign_opt);
 795                 opts->gpg_sign_opt = git_config_bool(var, value) ?
 796                         xstrdup("-S") : NULL;
 797                 return 0;
 798         }
 799
 800         if (!strcmp(var, "rebase.autostash")) {
 801                 opts->autostash = git_config_bool(var, value);
 802                 return 0;
 803         }
 804
 805         if (!strcmp(var, "rebase.rebasemerges")) {
 806                 opts->config_rebase_merges = git_parse_maybe_bool(value);
 807                 if (opts->config_rebase_merges < 0) {
 808                         opts->config_rebase_merges = 1;
 809                         parse_rebase_merges_value(opts, value);
 810                 } else {
 811                         opts->rebase_cousins = 0;
 812                 }
 813                 return 0;
 814         }
 815
 816         if (!strcmp(var, "rebase.updaterefs")) {
 817                 opts->config_update_refs = git_config_bool(var, value);
 818                 return 0;
 819         }
 820
 821         if (!strcmp(var, "rebase.reschedulefailedexec")) {
 822                 opts->reschedule_failed_exec = git_config_bool(var, value);
 823                 return 0;
 824         }
 825
 826         if (!strcmp(var, "rebase.forkpoint")) {
 827                 opts->fork_point = git_config_bool(var, value) ? -1 : 0;
 828                 return 0;
 829         }
 830
 831         if (!strcmp(var, "rebase.backend")) {
 832                 return git_config_string(&opts->default_backend, var, value);
 833         }
 834
 835         return git_default_config(var, value, ctx, data);
 836 }
 837
 838 static int checkout_up_to_date(struct rebase_options *options)
 839 {
 840         struct strbuf buf = STRBUF_INIT;
 841         struct reset_head_opts ropts = { 0 };
 842         int ret = 0;
 843
 844         strbuf_addf(&buf, "%s: checkout %s",
 845                     options->reflog_action, options->switch_to);
 846         ropts.oid = &options->orig_head->object.oid;
 847         ropts.branch = options->head_name;
 848         ropts.flags = RESET_HEAD_RUN_POST_CHECKOUT_HOOK;
 849         if (!ropts.branch)
 850                 ropts.flags |=  RESET_HEAD_DETACH;
 851         ropts.head_msg = buf.buf;
 852         if (reset_head(the_repository, &ropts) < 0)
 853                 ret = error(_("could not switch to %s"), options->switch_to);
 854         strbuf_release(&buf);
 855
 856         return ret;
 857 }
 858
 859 /*
 860  * Determines whether the commits in from..to are linear, i.e. contain
 861  * no merge commits. This function *expects* `from` to be an ancestor of
 862  * `to`.
 863  */
 864 static int is_linear_history(struct commit *from, struct commit *to)
 865 {
 866         while (to && to != from) {
 867                 repo_parse_commit(the_repository, to);
 868                 if (!to->parents)
 869                         return 1;
 870                 if (to->parents->next)
 871                         return 0;
 872                 to = to->parents->item;
 873         }
 874         return 1;
 875 }
 876
 877 static int can_fast_forward(struct commit *onto, struct commit *upstream,
 878                             struct commit *restrict_revision,
 879                             struct commit *head, struct object_id *branch_base)
 880 {
 881         struct commit_list *merge_bases = NULL;
 882         int res = 0;
 883
 884         if (is_null_oid(branch_base))
 885                 goto done; /* fill_branch_base() found multiple merge bases */
 886
 887         if (!oideq(branch_base, &onto->object.oid))
 888                 goto done;
 889
 890         if (restrict_revision && !oideq(&restrict_revision->object.oid, branch_base))
 891                 goto done;
 892
 893         if (!upstream)
 894                 goto done;
 895
 896         merge_bases = repo_get_merge_bases(the_repository, upstream, head);
 897         if (!merge_bases || merge_bases->next)
 898                 goto done;
 899
 900         if (!oideq(&onto->object.oid, &merge_bases->item->object.oid))
 901                 goto done;
 902
 903         res = 1;
 904
 905 done:
 906         free_commit_list(merge_bases);
 907         return res && is_linear_history(onto, head);
 908 }
 909
 910 static void fill_branch_base(struct rebase_options *options,
 911                             struct object_id *branch_base)
 912 {
 913         struct commit_list *merge_bases = NULL;
 914
 915         merge_bases = repo_get_merge_bases(the_repository, options->onto,
 916                                            options->orig_head);
 917         if (!merge_bases || merge_bases->next)
 918                 oidcpy(branch_base, null_oid());
 919         else
 920                 oidcpy(branch_base, &merge_bases->item->object.oid);
 921
 922         free_commit_list(merge_bases);
 923 }
 924
 925 static int parse_opt_am(const struct option *opt, const char *arg, int unset)
 926 {
 927         struct rebase_options *opts = opt->value;
 928
 929         BUG_ON_OPT_NEG(unset);
 930         BUG_ON_OPT_ARG(arg);
 931
 932         if (opts->type != REBASE_UNSPECIFIED && opts->type != REBASE_APPLY)
 933             die(_("apply options and merge options cannot be used together"));
 934
 935         opts->type = REBASE_APPLY;
 936
 937         return 0;
 938 }
 939
 940 /* -i followed by -m is still -i */
 941 static int parse_opt_merge(const struct option *opt, const char *arg, int unset)
 942 {
 943         struct rebase_options *opts = opt->value;
 944
 945         BUG_ON_OPT_NEG(unset);
 946         BUG_ON_OPT_ARG(arg);
 947
 948         if (opts->type != REBASE_UNSPECIFIED && opts->type != REBASE_MERGE)
 949             die(_("apply options and merge options cannot be used together"));
 950
 951         opts->type = REBASE_MERGE;
 952
 953         return 0;
 954 }
 955
 956 /* -i followed by -r is still explicitly interactive, but -r alone is not */
 957 static int parse_opt_interactive(const struct option *opt, const char *arg,
 958                                  int unset)
 959 {
 960         struct rebase_options *opts = opt->value;
 961
 962         BUG_ON_OPT_NEG(unset);
 963         BUG_ON_OPT_ARG(arg);
 964
 965         if (opts->type != REBASE_UNSPECIFIED && opts->type != REBASE_MERGE)
 966             die(_("apply options and merge options cannot be used together"));
 967
 968         opts->type = REBASE_MERGE;
 969         opts->flags |= REBASE_INTERACTIVE_EXPLICIT;
 970
 971         return 0;
 972 }
 973
 974 static enum empty_type parse_empty_value(const char *value)
 975 {
 976         if (!strcasecmp(value, "drop"))
 977                 return EMPTY_DROP;
 978         else if (!strcasecmp(value, "keep"))
 979                 return EMPTY_KEEP;
 980         else if (!strcasecmp(value, "ask"))
 981                 return EMPTY_ASK;
 982
 983         die(_("unrecognized empty type '%s'; valid values are \"drop\", \"keep\", and \"ask\"."), value);
 984 }
 985
 986 static int parse_opt_empty(const struct option *opt, const char *arg, int unset)
 987 {
 988         struct rebase_options *options = opt->value;
 989         enum empty_type value = parse_empty_value(arg);
 990
 991         BUG_ON_OPT_NEG(unset);
 992
 993         options->empty = value;
 994         return 0;
 995 }
 996
 997 static int parse_opt_rebase_merges(const struct option *opt, const char *arg, int unset)
 998 {
 999         struct rebase_options *options = opt->value;
1000
1001         options->rebase_merges = !unset;
1002         options->rebase_cousins = 0;
1003
1004         if (arg) {
1005                 if (!*arg) {
1006                         warning(_("--rebase-merges with an empty string "
1007                                   "argument is deprecated and will stop "
1008                                   "working in a future version of Git. Use "
1009                                   "--rebase-merges without an argument "
1010                                   "instead, which does the same thing."));
1011                         return 0;
1012                 }
1013                 parse_rebase_merges_value(options, arg);
1014         }
1015
1016         return 0;
1017 }
1018
1019 static void NORETURN error_on_missing_default_upstream(void)
1020 {
1021         struct branch *current_branch = branch_get(NULL);
1022
1023         printf(_("%s\n"
1024                  "Please specify which branch you want to rebase against.\n"
1025                  "See git-rebase(1) for details.\n"
1026                  "\n"
1027                  "    git rebase '<branch>'\n"
1028                  "\n"),
1029                 current_branch ? _("There is no tracking information for "
1030                         "the current branch.") :
1031                         _("You are not currently on a branch."));
1032
1033         if (current_branch) {
1034                 const char *remote = current_branch->remote_name;
1035
1036                 if (!remote)
1037                         remote = _("<remote>");
1038
1039                 printf(_("If you wish to set tracking information for this "
1040                          "branch you can do so with:\n"
1041                          "\n"
1042                          "    git branch --set-upstream-to=%s/<branch> %s\n"
1043                          "\n"),
1044                        remote, current_branch->name);
1045         }
1046         exit(1);
1047 }
1048
1049 static int check_exec_cmd(const char *cmd)
1050 {
1051         if (strchr(cmd, '\n'))
1052                 return error(_("exec commands cannot contain newlines"));
1053
1054         /* Does the command consist purely of whitespace? */
1055         if (!cmd[strspn(cmd, " \t\r\f\v")])
1056                 return error(_("empty exec command"));
1057
1058         return 0;
1059 }
1060
1061 int cmd_rebase(int argc, const char **argv, const char *prefix)
1062 {
1063         struct rebase_options options = REBASE_OPTIONS_INIT;
1064         const char *branch_name;
1065         int ret, flags, total_argc, in_progress = 0;
1066         int keep_base = 0;
1067         int ok_to_skip_pre_rebase = 0;
1068         struct strbuf msg = STRBUF_INIT;
1069         struct strbuf revisions = STRBUF_INIT;
1070         struct strbuf buf = STRBUF_INIT;
1071         struct object_id branch_base;
1072         int ignore_whitespace = 0;
1073         const char *gpg_sign = NULL;
1074         struct object_id squash_onto;
1075         char *squash_onto_name = NULL;
1076         char *keep_base_onto_name = NULL;
1077         int reschedule_failed_exec = -1;
1078         int allow_preemptive_ff = 1;
1079         int preserve_merges_selected = 0;
1080         struct reset_head_opts ropts = { 0 };
1081         struct option builtin_rebase_options[] = {
1082                 OPT_STRING(0, "onto", &options.onto_name,
1083                            N_("revision"),
1084                            N_("rebase onto given branch instead of upstream")),
1085                 OPT_BOOL(0, "keep-base", &keep_base,
1086                          N_("use the merge-base of upstream and branch as the current base")),
1087                 OPT_BOOL(0, "no-verify", &ok_to_skip_pre_rebase,
1088                          N_("allow pre-rebase hook to run")),
1089                 OPT_NEGBIT('q', "quiet", &options.flags,
1090                            N_("be quiet. implies --no-stat"),
1091                            REBASE_NO_QUIET | REBASE_VERBOSE | REBASE_DIFFSTAT),
1092                 OPT_BIT('v', "verbose", &options.flags,
1093                         N_("display a diffstat of what changed upstream"),
1094                         REBASE_NO_QUIET | REBASE_VERBOSE | REBASE_DIFFSTAT),
1095                 {OPTION_NEGBIT, 'n', "no-stat", &options.flags, NULL,
1096                         N_("do not show diffstat of what changed upstream"),
1097                         PARSE_OPT_NOARG, NULL, REBASE_DIFFSTAT },
1098                 OPT_BOOL(0, "signoff", &options.signoff,
1099                          N_("add a Signed-off-by trailer to each commit")),
1100                 OPT_BOOL(0, "committer-date-is-author-date",
1101                          &options.committer_date_is_author_date,
1102                          N_("make committer date match author date")),
1103                 OPT_BOOL(0, "reset-author-date", &options.ignore_date,
1104                          N_("ignore author date and use current date")),
1105                 OPT_HIDDEN_BOOL(0, "ignore-date", &options.ignore_date,
1106                                 N_("synonym of --reset-author-date")),
1107                 OPT_PASSTHRU_ARGV('C', NULL, &options.git_am_opts, N_("n"),
1108                                   N_("passed to 'git apply'"), 0),
1109                 OPT_BOOL(0, "ignore-whitespace", &ignore_whitespace,
1110                          N_("ignore changes in whitespace")),
1111                 OPT_PASSTHRU_ARGV(0, "whitespace", &options.git_am_opts,
1112                                   N_("action"), N_("passed to 'git apply'"), 0),
1113                 OPT_BIT('f', "force-rebase", &options.flags,
1114                         N_("cherry-pick all commits, even if unchanged"),
1115                         REBASE_FORCE),
1116                 OPT_BIT(0, "no-ff", &options.flags,
1117                         N_("cherry-pick all commits, even if unchanged"),
1118                         REBASE_FORCE),
1119                 OPT_CMDMODE(0, "continue", &options.action, N_("continue"),
1120                             ACTION_CONTINUE),
1121                 OPT_CMDMODE(0, "skip", &options.action,
1122                             N_("skip current patch and continue"), ACTION_SKIP),
1123                 OPT_CMDMODE(0, "abort", &options.action,
1124                             N_("abort and check out the original branch"),
1125                             ACTION_ABORT),
1126                 OPT_CMDMODE(0, "quit", &options.action,
1127                             N_("abort but keep HEAD where it is"), ACTION_QUIT),
1128                 OPT_CMDMODE(0, "edit-todo", &options.action, N_("edit the todo list "
1129                             "during an interactive rebase"), ACTION_EDIT_TODO),
1130                 OPT_CMDMODE(0, "show-current-patch", &options.action,
1131                             N_("show the patch file being applied or merged"),
1132                             ACTION_SHOW_CURRENT_PATCH),
1133                 OPT_CALLBACK_F(0, "apply", &options, NULL,
1134                         N_("use apply strategies to rebase"),
1135                         PARSE_OPT_NOARG | PARSE_OPT_NONEG,
1136                         parse_opt_am),
1137                 OPT_CALLBACK_F('m', "merge", &options, NULL,
1138                         N_("use merging strategies to rebase"),
1139                         PARSE_OPT_NOARG | PARSE_OPT_NONEG,
1140                         parse_opt_merge),
1141                 OPT_CALLBACK_F('i', "interactive", &options, NULL,
1142                         N_("let the user edit the list of commits to rebase"),
1143                         PARSE_OPT_NOARG | PARSE_OPT_NONEG,
1144                         parse_opt_interactive),
1145                 OPT_SET_INT_F('p', "preserve-merges", &preserve_merges_selected,
1146                               N_("(REMOVED) was: try to recreate merges "
1147                                  "instead of ignoring them"),
1148                               1, PARSE_OPT_HIDDEN),
1149                 OPT_RERERE_AUTOUPDATE(&options.allow_rerere_autoupdate),
1150                 OPT_CALLBACK_F(0, "empty", &options, "{drop,keep,ask}",
1151                                N_("how to handle commits that become empty"),
1152                                PARSE_OPT_NONEG, parse_opt_empty),
1153                 OPT_CALLBACK_F('k', "keep-empty", &options, NULL,
1154                         N_("keep commits which start empty"),
1155                         PARSE_OPT_NOARG | PARSE_OPT_HIDDEN,
1156                         parse_opt_keep_empty),
1157                 OPT_BOOL(0, "autosquash", &options.autosquash,
1158                          N_("move commits that begin with "
1159                             "squash!/fixup! under -i")),
1160                 OPT_BOOL(0, "update-refs", &options.update_refs,
1161                          N_("update branches that point to commits "
1162                             "that are being rebased")),
1163                 { OPTION_STRING, 'S', "gpg-sign", &gpg_sign, N_("key-id"),
1164                         N_("GPG-sign commits"),
1165                         PARSE_OPT_OPTARG, NULL, (intptr_t) "" },
1166                 OPT_AUTOSTASH(&options.autostash),
1167                 OPT_STRING_LIST('x', "exec", &options.exec, N_("exec"),
1168                                 N_("add exec lines after each commit of the "
1169                                    "editable list")),
1170                 OPT_BOOL_F(0, "allow-empty-message",
1171                            &options.allow_empty_message,
1172                            N_("allow rebasing commits with empty messages"),
1173                            PARSE_OPT_HIDDEN),
1174                 OPT_CALLBACK_F('r', "rebase-merges", &options, N_("mode"),
1175                         N_("try to rebase merges instead of skipping them"),
1176                         PARSE_OPT_OPTARG, parse_opt_rebase_merges),
1177                 OPT_BOOL(0, "fork-point", &options.fork_point,
1178                          N_("use 'merge-base --fork-point' to refine upstream")),
1179                 OPT_STRING('s', "strategy", &options.strategy,
1180                            N_("strategy"), N_("use the given merge strategy")),
1181                 OPT_STRING_LIST('X', "strategy-option", &options.strategy_opts,
1182                                 N_("option"),
1183                                 N_("pass the argument through to the merge "
1184                                    "strategy")),
1185                 OPT_BOOL(0, "root", &options.root,
1186                          N_("rebase all reachable commits up to the root(s)")),
1187                 OPT_BOOL(0, "reschedule-failed-exec",
1188                          &reschedule_failed_exec,
1189                          N_("automatically re-schedule any `exec` that fails")),
1190                 OPT_BOOL(0, "reapply-cherry-picks", &options.reapply_cherry_picks,
1191                          N_("apply all changes, even those already present upstream")),
1192                 OPT_END(),
1193         };
1194         int i;
1195
1196         if (argc == 2 && !strcmp(argv[1], "-h"))
1197                 usage_with_options(builtin_rebase_usage,
1198                                    builtin_rebase_options);
1199
1200         prepare_repo_settings(the_repository);
1201         the_repository->settings.command_requires_full_index = 0;
1202
1203         git_config(rebase_config, &options);
1204         /* options.gpg_sign_opt will be either "-S" or NULL */
1205         gpg_sign = options.gpg_sign_opt ? "" : NULL;
1206         FREE_AND_NULL(options.gpg_sign_opt);
1207
1208         strbuf_reset(&buf);
1209         strbuf_addf(&buf, "%s/applying", apply_dir());
1210         if(file_exists(buf.buf))
1211                 die(_("It looks like 'git am' is in progress. Cannot rebase."));
1212
1213         if (is_directory(apply_dir())) {
1214                 options.type = REBASE_APPLY;
1215                 options.state_dir = apply_dir();
1216         } else if (is_directory(merge_dir())) {
1217                 strbuf_reset(&buf);
1218                 strbuf_addf(&buf, "%s/rewritten", merge_dir());
1219                 if (!(options.action == ACTION_ABORT) && is_directory(buf.buf)) {
1220                         die(_("`rebase --preserve-merges` (-p) is no longer supported.\n"
1221                         "Use `git rebase --abort` to terminate current rebase.\n"
1222                         "Or downgrade to v2.33, or earlier, to complete the rebase."));
1223                 } else {
1224                         strbuf_reset(&buf);
1225                         strbuf_addf(&buf, "%s/interactive", merge_dir());
1226                         options.type = REBASE_MERGE;
1227                         if (file_exists(buf.buf))
1228                                 options.flags |= REBASE_INTERACTIVE_EXPLICIT;
1229                 }
1230                 options.state_dir = merge_dir();
1231         }
1232
1233         if (options.type != REBASE_UNSPECIFIED)
1234                 in_progress = 1;
1235
1236         total_argc = argc;
1237         argc = parse_options(argc, argv, prefix,
1238                              builtin_rebase_options,
1239                              builtin_rebase_usage, 0);
1240
1241         if (preserve_merges_selected)
1242                 die(_("--preserve-merges was replaced by --rebase-merges\n"
1243                         "Note: Your `pull.rebase` configuration may also be set to 'preserve',\n"
1244                         "which is no longer supported; use 'merges' instead"));
1245
1246         if (options.action != ACTION_NONE && total_argc != 2) {
1247                 usage_with_options(builtin_rebase_usage,
1248                                    builtin_rebase_options);
1249         }
1250
1251         if (argc > 2)
1252                 usage_with_options(builtin_rebase_usage,
1253                                    builtin_rebase_options);
1254
1255         if (keep_base) {
1256                 if (options.onto_name)
1257                         die(_("options '%s' and '%s' cannot be used together"), "--keep-base", "--onto");
1258                 if (options.root)
1259                         die(_("options '%s' and '%s' cannot be used together"), "--keep-base", "--root");
1260                 /*
1261                  * --keep-base defaults to --no-fork-point to keep the
1262                  * base the same.
1263                  */
1264                 if (options.fork_point < 0)
1265                         options.fork_point = 0;
1266         }
1267         if (options.root && options.fork_point > 0)
1268                 die(_("options '%s' and '%s' cannot be used together"), "--root", "--fork-point");
1269
1270         if (options.action != ACTION_NONE && !in_progress)
1271                 die(_("No rebase in progress?"));
1272
1273         if (options.action == ACTION_EDIT_TODO && !is_merge(&options))
1274                 die(_("The --edit-todo action can only be used during "
1275                       "interactive rebase."));
1276
1277         if (trace2_is_enabled()) {
1278                 if (is_merge(&options))
1279                         trace2_cmd_mode("interactive");
1280                 else if (options.exec.nr)
1281                         trace2_cmd_mode("interactive-exec");
1282                 else
1283                         trace2_cmd_mode(action_names[options.action]);
1284         }
1285
1286         options.reflog_action = getenv(GIT_REFLOG_ACTION_ENVIRONMENT);
1287         options.reflog_action =
1288                 xstrdup(options.reflog_action ? options.reflog_action : "rebase");
1289
1290         switch (options.action) {
1291         case ACTION_CONTINUE: {
1292                 struct object_id head;
1293                 struct lock_file lock_file = LOCK_INIT;
1294                 int fd;
1295
1296                 /* Sanity check */
1297                 if (repo_get_oid(the_repository, "HEAD", &head))
1298                         die(_("Cannot read HEAD"));
1299
1300                 fd = repo_hold_locked_index(the_repository, &lock_file, 0);
1301                 if (repo_read_index(the_repository) < 0)
1302                         die(_("could not read index"));
1303                 refresh_index(the_repository->index, REFRESH_QUIET, NULL, NULL,
1304                               NULL);
1305                 if (0 <= fd)
1306                         repo_update_index_if_able(the_repository, &lock_file);
1307                 rollback_lock_file(&lock_file);
1308
1309                 if (has_unstaged_changes(the_repository, 1)) {
1310                         puts(_("You must edit all merge conflicts and then\n"
1311                                "mark them as resolved using git add"));
1312                         exit(1);
1313                 }
1314                 if (read_basic_state(&options))
1315                         exit(1);
1316                 goto run_rebase;
1317         }
1318         case ACTION_SKIP: {
1319                 struct string_list merge_rr = STRING_LIST_INIT_DUP;
1320
1321                 rerere_clear(the_repository, &merge_rr);
1322                 string_list_clear(&merge_rr, 1);
1323                 ropts.flags = RESET_HEAD_HARD;
1324                 if (reset_head(the_repository, &ropts) < 0)
1325                         die(_("could not discard worktree changes"));
1326                 remove_branch_state(the_repository, 0);
1327                 if (read_basic_state(&options))
1328                         exit(1);
1329                 goto run_rebase;
1330         }
1331         case ACTION_ABORT: {
1332                 struct string_list merge_rr = STRING_LIST_INIT_DUP;
1333                 struct strbuf head_msg = STRBUF_INIT;
1334
1335                 rerere_clear(the_repository, &merge_rr);
1336                 string_list_clear(&merge_rr, 1);
1337
1338                 if (read_basic_state(&options))
1339                         exit(1);
1340
1341                 strbuf_addf(&head_msg, "%s (abort): returning to %s",
1342                             options.reflog_action,
1343                             options.head_name ? options.head_name
1344                                               : oid_to_hex(&options.orig_head->object.oid));
1345                 ropts.oid = &options.orig_head->object.oid;
1346                 ropts.head_msg = head_msg.buf;
1347                 ropts.branch = options.head_name;
1348                 ropts.flags = RESET_HEAD_HARD;
1349                 if (reset_head(the_repository, &ropts) < 0)
1350                         die(_("could not move back to %s"),
1351                             oid_to_hex(&options.orig_head->object.oid));
1352                 strbuf_release(&head_msg);
1353                 remove_branch_state(the_repository, 0);
1354                 ret = finish_rebase(&options);
1355                 goto cleanup;
1356         }
1357         case ACTION_QUIT: {
1358                 save_autostash(state_dir_path("autostash", &options));
1359                 if (options.type == REBASE_MERGE) {
1360                         struct replay_opts replay = REPLAY_OPTS_INIT;
1361
1362                         replay.action = REPLAY_INTERACTIVE_REBASE;
1363                         ret = sequencer_remove_state(&replay);
1364                         replay_opts_release(&replay);
1365                 } else {
1366                         strbuf_reset(&buf);
1367                         strbuf_addstr(&buf, options.state_dir);
1368                         ret = remove_dir_recursively(&buf, 0);
1369                         if (ret)
1370                                 error(_("could not remove '%s'"),
1371                                        options.state_dir);
1372                 }
1373                 goto cleanup;
1374         }
1375         case ACTION_EDIT_TODO:
1376                 options.dont_finish_rebase = 1;
1377                 goto run_rebase;
1378         case ACTION_SHOW_CURRENT_PATCH:
1379                 options.dont_finish_rebase = 1;
1380                 goto run_rebase;
1381         case ACTION_NONE:
1382                 break;
1383         default:
1384                 BUG("action: %d", options.action);
1385         }
1386
1387         /* Make sure no rebase is in progress */
1388         if (in_progress) {
1389                 const char *last_slash = strrchr(options.state_dir, '/');
1390                 const char *state_dir_base =
1391                         last_slash ? last_slash + 1 : options.state_dir;
1392                 const char *cmd_live_rebase =
1393                         "git rebase (--continue | --abort | --skip)";
1394                 strbuf_reset(&buf);
1395                 strbuf_addf(&buf, "rm -fr \"%s\"", options.state_dir);
1396                 die(_("It seems that there is already a %s directory, and\n"
1397                       "I wonder if you are in the middle of another rebase.  "
1398                       "If that is the\n"
1399                       "case, please try\n\t%s\n"
1400                       "If that is not the case, please\n\t%s\n"
1401                       "and run me again.  I am stopping in case you still "
1402                       "have something\n"
1403                       "valuable there.\n"),
1404                     state_dir_base, cmd_live_rebase, buf.buf);
1405         }
1406
1407         if ((options.flags & REBASE_INTERACTIVE_EXPLICIT) ||
1408             (options.action != ACTION_NONE) ||
1409             (options.exec.nr > 0) ||
1410             (options.autosquash == -1 && options.config_autosquash == 1) ||
1411             options.autosquash == 1) {
1412                 allow_preemptive_ff = 0;
1413         }
1414         if (options.committer_date_is_author_date || options.ignore_date)
1415                 options.flags |= REBASE_FORCE;
1416
1417         for (i = 0; i < options.git_am_opts.nr; i++) {
1418                 const char *option = options.git_am_opts.v[i], *p;
1419                 if (!strcmp(option, "--whitespace=fix") ||
1420                     !strcmp(option, "--whitespace=strip"))
1421                         allow_preemptive_ff = 0;
1422                 else if (skip_prefix(option, "-C", &p)) {
1423                         while (*p)
1424                                 if (!isdigit(*(p++)))
1425                                         die(_("switch `C' expects a "
1426                                               "numerical value"));
1427                 } else if (skip_prefix(option, "--whitespace=", &p)) {
1428                         if (*p && strcmp(p, "warn") && strcmp(p, "nowarn") &&
1429                             strcmp(p, "error") && strcmp(p, "error-all"))
1430                                 die("Invalid whitespace option: '%s'", p);
1431                 }
1432         }
1433
1434         for (i = 0; i < options.exec.nr; i++)
1435                 if (check_exec_cmd(options.exec.items[i].string))
1436                         exit(1);
1437
1438         if (!(options.flags & REBASE_NO_QUIET))
1439                 strvec_push(&options.git_am_opts, "-q");
1440
1441         if (options.empty != EMPTY_UNSPECIFIED)
1442                 imply_merge(&options, "--empty");
1443
1444         if (options.reapply_cherry_picks < 0)
1445                 /*
1446                  * We default to --no-reapply-cherry-picks unless
1447                  * --keep-base is given; when --keep-base is given, we want
1448                  * to default to --reapply-cherry-picks.
1449                  */
1450                 options.reapply_cherry_picks = keep_base;
1451         else if (!keep_base)
1452                 /*
1453                  * The apply backend always searches for and drops cherry
1454                  * picks.  This is often not wanted with --keep-base, so
1455                  * --keep-base allows --reapply-cherry-picks to be
1456                  * simulated by altering the upstream such that
1457                  * cherry-picks cannot be detected and thus all commits are
1458                  * reapplied.  Thus, --[no-]reapply-cherry-picks is
1459                  * supported when --keep-base is specified, but not when
1460                  * --keep-base is left out.
1461                  */
1462                 imply_merge(&options, options.reapply_cherry_picks ?
1463                                           "--reapply-cherry-picks" :
1464                                           "--no-reapply-cherry-picks");
1465
1466         if (gpg_sign)
1467                 options.gpg_sign_opt = xstrfmt("-S%s", gpg_sign);
1468
1469         if (options.exec.nr)
1470                 imply_merge(&options, "--exec");
1471
1472         if (options.type == REBASE_APPLY) {
1473                 if (ignore_whitespace)
1474                         strvec_push(&options.git_am_opts,
1475                                     "--ignore-whitespace");
1476                 if (options.committer_date_is_author_date)
1477                         strvec_push(&options.git_am_opts,
1478                                     "--committer-date-is-author-date");
1479                 if (options.ignore_date)
1480                         strvec_push(&options.git_am_opts, "--ignore-date");
1481         } else {
1482                 /* REBASE_MERGE */
1483                 if (ignore_whitespace) {
1484                         string_list_append(&options.strategy_opts,
1485                                            "ignore-space-change");
1486                 }
1487         }
1488
1489         if (options.strategy_opts.nr && !options.strategy)
1490                 options.strategy = "ort";
1491
1492         if (options.strategy) {
1493                 options.strategy = xstrdup(options.strategy);
1494                 switch (options.type) {
1495                 case REBASE_APPLY:
1496                         die(_("--strategy requires --merge or --interactive"));
1497                 case REBASE_MERGE:
1498                         /* compatible */
1499                         break;
1500                 case REBASE_UNSPECIFIED:
1501                         options.type = REBASE_MERGE;
1502                         break;
1503                 default:
1504                         BUG("unhandled rebase type (%d)", options.type);
1505                 }
1506         }
1507
1508         if (options.type == REBASE_MERGE)
1509                 imply_merge(&options, "--merge");
1510
1511         if (options.root && !options.onto_name)
1512                 imply_merge(&options, "--root without --onto");
1513
1514         if (isatty(2) && options.flags & REBASE_NO_QUIET)
1515                 strbuf_addstr(&options.git_format_patch_opt, " --progress");
1516
1517         if (options.git_am_opts.nr || options.type == REBASE_APPLY) {
1518                 /* all am options except -q are compatible only with --apply */
1519                 for (i = options.git_am_opts.nr - 1; i >= 0; i--)
1520                         if (strcmp(options.git_am_opts.v[i], "-q"))
1521                                 break;
1522
1523                 if (i >= 0 || options.type == REBASE_APPLY) {
1524                         if (is_merge(&options))
1525                                 die(_("apply options and merge options "
1526                                           "cannot be used together"));
1527                         else if (options.autosquash == -1 && options.config_autosquash == 1)
1528                                 die(_("apply options are incompatible with rebase.autoSquash.  Consider adding --no-autosquash"));
1529                         else if (options.rebase_merges == -1 && options.config_rebase_merges == 1)
1530                                 die(_("apply options are incompatible with rebase.rebaseMerges.  Consider adding --no-rebase-merges"));
1531                         else if (options.update_refs == -1 && options.config_update_refs == 1)
1532                                 die(_("apply options are incompatible with rebase.updateRefs.  Consider adding --no-update-refs"));
1533                         else
1534                                 options.type = REBASE_APPLY;
1535                 }
1536         }
1537
1538         if (options.update_refs == 1)
1539                 imply_merge(&options, "--update-refs");
1540         options.update_refs = (options.update_refs >= 0) ? options.update_refs :
1541                              ((options.config_update_refs >= 0) ? options.config_update_refs : 0);
1542
1543         if (options.rebase_merges == 1)
1544                 imply_merge(&options, "--rebase-merges");
1545         options.rebase_merges = (options.rebase_merges >= 0) ? options.rebase_merges :
1546                                 ((options.config_rebase_merges >= 0) ? options.config_rebase_merges : 0);
1547
1548         if (options.autosquash == 1)
1549                 imply_merge(&options, "--autosquash");
1550         options.autosquash = (options.autosquash >= 0) ? options.autosquash :
1551                              ((options.config_autosquash >= 0) ? options.config_autosquash : 0);
1552
1553         if (options.type == REBASE_UNSPECIFIED) {
1554                 if (!strcmp(options.default_backend, "merge"))
1555                         imply_merge(&options, "--merge");
1556                 else if (!strcmp(options.default_backend, "apply"))
1557                         options.type = REBASE_APPLY;
1558                 else
1559                         die(_("Unknown rebase backend: %s"),
1560                             options.default_backend);
1561         }
1562
1563         if (options.type == REBASE_MERGE &&
1564             !options.strategy &&
1565             getenv("GIT_TEST_MERGE_ALGORITHM"))
1566                 options.strategy = xstrdup(getenv("GIT_TEST_MERGE_ALGORITHM"));
1567
1568         switch (options.type) {
1569         case REBASE_MERGE:
1570                 options.state_dir = merge_dir();
1571                 break;
1572         case REBASE_APPLY:
1573                 options.state_dir = apply_dir();
1574                 break;
1575         default:
1576                 BUG("options.type was just set above; should be unreachable.");
1577         }
1578
1579         if (options.empty == EMPTY_UNSPECIFIED) {
1580                 if (options.flags & REBASE_INTERACTIVE_EXPLICIT)
1581                         options.empty = EMPTY_ASK;
1582                 else if (options.exec.nr > 0)
1583                         options.empty = EMPTY_KEEP;
1584                 else
1585                         options.empty = EMPTY_DROP;
1586         }
1587         if (reschedule_failed_exec > 0 && !is_merge(&options))
1588                 die(_("--reschedule-failed-exec requires "
1589                       "--exec or --interactive"));
1590         if (reschedule_failed_exec >= 0)
1591                 options.reschedule_failed_exec = reschedule_failed_exec;
1592
1593         if (options.signoff) {
1594                 strvec_push(&options.git_am_opts, "--signoff");
1595                 options.flags |= REBASE_FORCE;
1596         }
1597
1598         if (!options.root) {
1599                 if (argc < 1) {
1600                         struct branch *branch;
1601
1602                         branch = branch_get(NULL);
1603                         options.upstream_name = branch_get_upstream(branch,
1604                                                                     NULL);
1605                         if (!options.upstream_name)
1606                                 error_on_missing_default_upstream();
1607                         if (options.fork_point < 0)
1608                                 options.fork_point = 1;
1609                 } else {
1610                         options.upstream_name = argv[0];
1611                         argc--;
1612                         argv++;
1613                         if (!strcmp(options.upstream_name, "-"))
1614                                 options.upstream_name = "@{-1}";
1615                 }
1616                 options.upstream =
1617                         lookup_commit_reference_by_name(options.upstream_name);
1618                 if (!options.upstream)
1619                         die(_("invalid upstream '%s'"), options.upstream_name);
1620                 options.upstream_arg = options.upstream_name;
1621         } else {
1622                 if (!options.onto_name) {
1623                         if (commit_tree("", 0, the_hash_algo->empty_tree, NULL,
1624                                         &squash_onto, NULL, NULL) < 0)
1625                                 die(_("Could not create new root commit"));
1626                         options.squash_onto = &squash_onto;
1627                         options.onto_name = squash_onto_name =
1628                                 xstrdup(oid_to_hex(&squash_onto));
1629                 } else
1630                         options.root_with_onto = 1;
1631
1632                 options.upstream_name = NULL;
1633                 options.upstream = NULL;
1634                 if (argc > 1)
1635                         usage_with_options(builtin_rebase_usage,
1636                                            builtin_rebase_options);
1637                 options.upstream_arg = "--root";
1638         }
1639
1640         /*
1641          * If the branch to rebase is given, that is the branch we will rebase
1642          * branch_name -- branch/commit being rebased, or
1643          *                HEAD (already detached)
1644          * orig_head -- commit object name of tip of the branch before rebasing
1645          * head_name -- refs/heads/<that-branch> or NULL (detached HEAD)
1646          */
1647         if (argc == 1) {
1648                 /* Is it "rebase other branchname" or "rebase other commit"? */
1649                 struct object_id branch_oid;
1650                 branch_name = argv[0];
1651                 options.switch_to = argv[0];
1652
1653                 /* Is it a local branch? */
1654                 strbuf_reset(&buf);
1655                 strbuf_addf(&buf, "refs/heads/%s", branch_name);
1656                 if (!read_ref(buf.buf, &branch_oid)) {
1657                         die_if_checked_out(buf.buf, 1);
1658                         options.head_name = xstrdup(buf.buf);
1659                         options.orig_head =
1660                                 lookup_commit_object(the_repository,
1661                                                      &branch_oid);
1662                 /* If not is it a valid ref (branch or commit)? */
1663                 } else {
1664                         options.orig_head =
1665                                 lookup_commit_reference_by_name(branch_name);
1666                         options.head_name = NULL;
1667                 }
1668                 if (!options.orig_head)
1669                         die(_("no such branch/commit '%s'"), branch_name);
1670         } else if (argc == 0) {
1671                 /* Do not need to switch branches, we are already on it. */
1672                 options.head_name =
1673                         xstrdup_or_null(resolve_ref_unsafe("HEAD", 0, NULL,
1674                                          &flags));
1675                 if (!options.head_name)
1676                         die(_("No such ref: %s"), "HEAD");
1677                 if (flags & REF_ISSYMREF) {
1678                         if (!skip_prefix(options.head_name,
1679                                          "refs/heads/", &branch_name))
1680                                 branch_name = options.head_name;
1681
1682                 } else {
1683                         FREE_AND_NULL(options.head_name);
1684                         branch_name = "HEAD";
1685                 }
1686                 options.orig_head = lookup_commit_reference_by_name("HEAD");
1687                 if (!options.orig_head)
1688                         die(_("Could not resolve HEAD to a commit"));
1689         } else
1690                 BUG("unexpected number of arguments left to parse");
1691
1692         /* Make sure the branch to rebase onto is valid. */
1693         if (keep_base) {
1694                 strbuf_reset(&buf);
1695                 strbuf_addstr(&buf, options.upstream_name);
1696                 strbuf_addstr(&buf, "...");
1697                 strbuf_addstr(&buf, branch_name);
1698                 options.onto_name = keep_base_onto_name = xstrdup(buf.buf);
1699         } else if (!options.onto_name)
1700                 options.onto_name = options.upstream_name;
1701         if (strstr(options.onto_name, "...")) {
1702                 if (repo_get_oid_mb(the_repository, options.onto_name, &branch_base) < 0) {
1703                         if (keep_base)
1704                                 die(_("'%s': need exactly one merge base with branch"),
1705                                     options.upstream_name);
1706                         else
1707                                 die(_("'%s': need exactly one merge base"),
1708                                     options.onto_name);
1709                 }
1710                 options.onto = lookup_commit_or_die(&branch_base,
1711                                                     options.onto_name);
1712         } else {
1713                 options.onto =
1714                         lookup_commit_reference_by_name(options.onto_name);
1715                 if (!options.onto)
1716                         die(_("Does not point to a valid commit '%s'"),
1717                                 options.onto_name);
1718                 fill_branch_base(&options, &branch_base);
1719         }
1720
1721         if (keep_base && options.reapply_cherry_picks)
1722                 options.upstream = options.onto;
1723
1724         if (options.fork_point > 0)
1725                 options.restrict_revision =
1726                         get_fork_point(options.upstream_name, options.orig_head);
1727
1728         if (repo_read_index(the_repository) < 0)
1729                 die(_("could not read index"));
1730
1731         if (options.autostash)
1732                 create_autostash(the_repository,
1733                                  state_dir_path("autostash", &options));
1734
1735
1736         if (require_clean_work_tree(the_repository, "rebase",
1737                                     _("Please commit or stash them."), 1, 1)) {
1738                 ret = -1;
1739                 goto cleanup;
1740         }
1741
1742         /*
1743          * Now we are rebasing commits upstream..orig_head (or with --root,
1744          * everything leading up to orig_head) on top of onto.
1745          */
1746
1747         /*
1748          * Check if we are already based on onto with linear history,
1749          * in which case we could fast-forward without replacing the commits
1750          * with new commits recreated by replaying their changes.
1751          */
1752         if (allow_preemptive_ff &&
1753             can_fast_forward(options.onto, options.upstream, options.restrict_revision,
1754                              options.orig_head, &branch_base)) {
1755                 int flag;
1756
1757                 if (!(options.flags & REBASE_FORCE)) {
1758                         /* Lazily switch to the target branch if needed... */
1759                         if (options.switch_to) {
1760                                 ret = checkout_up_to_date(&options);
1761                                 if (ret)
1762                                         goto cleanup;
1763                         }
1764
1765                         if (!(options.flags & REBASE_NO_QUIET))
1766                                 ; /* be quiet */
1767                         else if (!strcmp(branch_name, "HEAD") &&
1768                                  resolve_ref_unsafe("HEAD", 0, NULL, &flag))
1769                                 puts(_("HEAD is up to date."));
1770                         else
1771                                 printf(_("Current branch %s is up to date.\n"),
1772                                        branch_name);
1773                         ret = finish_rebase(&options);
1774                         goto cleanup;
1775                 } else if (!(options.flags & REBASE_NO_QUIET))
1776                         ; /* be quiet */
1777                 else if (!strcmp(branch_name, "HEAD") &&
1778                          resolve_ref_unsafe("HEAD", 0, NULL, &flag))
1779                         puts(_("HEAD is up to date, rebase forced."));
1780                 else
1781                         printf(_("Current branch %s is up to date, rebase "
1782                                  "forced.\n"), branch_name);
1783         }
1784
1785         /* If a hook exists, give it a chance to interrupt*/
1786         if (!ok_to_skip_pre_rebase &&
1787             run_hooks_l("pre-rebase", options.upstream_arg,
1788                         argc ? argv[0] : NULL, NULL))
1789                 die(_("The pre-rebase hook refused to rebase."));
1790
1791         if (options.flags & REBASE_DIFFSTAT) {
1792                 struct diff_options opts;
1793
1794                 if (options.flags & REBASE_VERBOSE) {
1795                         if (is_null_oid(&branch_base))
1796                                 printf(_("Changes to %s:\n"),
1797                                        oid_to_hex(&options.onto->object.oid));
1798                         else
1799                                 printf(_("Changes from %s to %s:\n"),
1800                                        oid_to_hex(&branch_base),
1801                                        oid_to_hex(&options.onto->object.oid));
1802                 }
1803
1804                 /* We want color (if set), but no pager */
1805                 repo_diff_setup(the_repository, &opts);
1806                 opts.stat_width = -1; /* use full terminal width */
1807                 opts.stat_graph_width = -1; /* respect statGraphWidth config */
1808                 opts.output_format |=
1809                         DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
1810                 opts.detect_rename = DIFF_DETECT_RENAME;
1811                 diff_setup_done(&opts);
1812                 diff_tree_oid(is_null_oid(&branch_base) ?
1813                               the_hash_algo->empty_tree : &branch_base,
1814                               &options.onto->object.oid, "", &opts);
1815                 diffcore_std(&opts);
1816                 diff_flush(&opts);
1817         }
1818
1819         if (is_merge(&options))
1820                 goto run_rebase;
1821
1822         /* Detach HEAD and reset the tree */
1823         if (options.flags & REBASE_NO_QUIET)
1824                 printf(_("First, rewinding head to replay your work on top of "
1825                          "it...\n"));
1826
1827         strbuf_addf(&msg, "%s (start): checkout %s",
1828                     options.reflog_action, options.onto_name);
1829         ropts.oid = &options.onto->object.oid;
1830         ropts.orig_head = &options.orig_head->object.oid,
1831         ropts.flags = RESET_HEAD_DETACH | RESET_ORIG_HEAD |
1832                         RESET_HEAD_RUN_POST_CHECKOUT_HOOK;
1833         ropts.head_msg = msg.buf;
1834         ropts.default_reflog_action = options.reflog_action;
1835         if (reset_head(the_repository, &ropts))
1836                 die(_("Could not detach HEAD"));
1837         strbuf_release(&msg);
1838
1839         /*
1840          * If the onto is a proper descendant of the tip of the branch, then
1841          * we just fast-forwarded.
1842          */
1843         if (oideq(&branch_base, &options.orig_head->object.oid)) {
1844                 printf(_("Fast-forwarded %s to %s.\n"),
1845                         branch_name, options.onto_name);
1846                 move_to_original_branch(&options);
1847                 ret = finish_rebase(&options);
1848                 goto cleanup;
1849         }
1850
1851         strbuf_addf(&revisions, "%s..%s",
1852                     options.root ? oid_to_hex(&options.onto->object.oid) :
1853                     (options.restrict_revision ?
1854                      oid_to_hex(&options.restrict_revision->object.oid) :
1855                      oid_to_hex(&options.upstream->object.oid)),
1856                     oid_to_hex(&options.orig_head->object.oid));
1857
1858         options.revisions = revisions.buf;
1859
1860 run_rebase:
1861         ret = run_specific_rebase(&options);
1862
1863 cleanup:
1864         strbuf_release(&buf);
1865         strbuf_release(&revisions);
1866         free(options.reflog_action);
1867         free(options.head_name);
1868         strvec_clear(&options.git_am_opts);
1869         free(options.gpg_sign_opt);
1870         string_list_clear(&options.exec, 0);
1871         free(options.strategy);
1872         string_list_clear(&options.strategy_opts, 0);
1873         strbuf_release(&options.git_format_patch_opt);
1874         free(squash_onto_name);
1875         free(keep_base_onto_name);
1876         return !!ret;
1877 }