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

   1 /*
   2  * "git rebase" builtin command
   3  *
   4  * Copyright (c) 2018 Pratik Karki
   5  */
   6
   7 #define USE_THE_INDEX_COMPATIBILITY_MACROS
   8 #include "builtin.h"
   9 #include "run-command.h"
  10 #include "exec-cmd.h"
  11 #include "argv-array.h"
  12 #include "dir.h"
  13 #include "packfile.h"
  14 #include "refs.h"
  15 #include "quote.h"
  16 #include "config.h"
  17 #include "cache-tree.h"
  18 #include "unpack-trees.h"
  19 #include "lockfile.h"
  20 #include "parse-options.h"
  21 #include "commit.h"
  22 #include "diff.h"
  23 #include "wt-status.h"
  24 #include "revision.h"
  25 #include "commit-reach.h"
  26 #include "rerere.h"
  27 #include "branch.h"
  28 #include "sequencer.h"
  29 #include "rebase-interactive.h"
  30
  31 static char const * const builtin_rebase_usage[] = {
  32         N_("git rebase [-i] [options] [--exec <cmd>] "
  33                 "[--onto <newbase> | --keep-base] [<upstream> [<branch>]]"),
  34         N_("git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] "
  35                 "--root [<branch>]"),
  36         N_("git rebase --continue | --abort | --skip | --edit-todo"),
  37         NULL
  38 };
  39
  40 static GIT_PATH_FUNC(path_squash_onto, "rebase-merge/squash-onto")
  41 static GIT_PATH_FUNC(path_interactive, "rebase-merge/interactive")
  42 static GIT_PATH_FUNC(apply_dir, "rebase-apply")
  43 static GIT_PATH_FUNC(merge_dir, "rebase-merge")
  44
  45 enum rebase_type {
  46         REBASE_UNSPECIFIED = -1,
  47         REBASE_APPLY,
  48         REBASE_MERGE,
  49         REBASE_PRESERVE_MERGES
  50 };
  51
  52 enum empty_type {
  53         EMPTY_UNSPECIFIED = -1,
  54         EMPTY_DROP,
  55         EMPTY_KEEP,
  56         EMPTY_ASK
  57 };
  58
  59 struct rebase_options {
  60         enum rebase_type type;
  61         enum empty_type empty;
  62         const char *default_backend;
  63         const char *state_dir;
  64         struct commit *upstream;
  65         const char *upstream_name;
  66         const char *upstream_arg;
  67         char *head_name;
  68         struct object_id orig_head;
  69         struct commit *onto;
  70         const char *onto_name;
  71         const char *revisions;
  72         const char *switch_to;
  73         int root, root_with_onto;
  74         struct object_id *squash_onto;
  75         struct commit *restrict_revision;
  76         int dont_finish_rebase;
  77         enum {
  78                 REBASE_NO_QUIET = 1<<0,
  79                 REBASE_VERBOSE = 1<<1,
  80                 REBASE_DIFFSTAT = 1<<2,
  81                 REBASE_FORCE = 1<<3,
  82                 REBASE_INTERACTIVE_EXPLICIT = 1<<4,
  83         } flags;
  84         struct argv_array git_am_opts;
  85         const char *action;
  86         int signoff;
  87         int allow_rerere_autoupdate;
  88         int autosquash;
  89         char *gpg_sign_opt;
  90         int autostash;
  91         int committer_date_is_author_date;
  92         char *cmd;
  93         int allow_empty_message;
  94         int rebase_merges, rebase_cousins;
  95         char *strategy, *strategy_opts;
  96         struct strbuf git_format_patch_opt;
  97         int reschedule_failed_exec;
  98         int use_legacy_rebase;
  99 };
 100
 101 #define REBASE_OPTIONS_INIT {                           \
 102                 .type = REBASE_UNSPECIFIED,             \
 103                 .empty = EMPTY_UNSPECIFIED,             \
 104                 .default_backend = "merge",             \
 105                 .flags = REBASE_NO_QUIET,               \
 106                 .git_am_opts = ARGV_ARRAY_INIT,         \
 107                 .git_format_patch_opt = STRBUF_INIT     \
 108         }
 109
 110 static struct replay_opts get_replay_opts(const struct rebase_options *opts)
 111 {
 112         struct replay_opts replay = REPLAY_OPTS_INIT;
 113
 114         replay.action = REPLAY_INTERACTIVE_REBASE;
 115         sequencer_init_config(&replay);
 116
 117         replay.signoff = opts->signoff;
 118         replay.allow_ff = !(opts->flags & REBASE_FORCE);
 119         if (opts->allow_rerere_autoupdate)
 120                 replay.allow_rerere_auto = opts->allow_rerere_autoupdate;
 121         replay.allow_empty = 1;
 122         replay.allow_empty_message = opts->allow_empty_message;
 123         replay.drop_redundant_commits = (opts->empty == EMPTY_DROP);
 124         replay.keep_redundant_commits = (opts->empty == EMPTY_KEEP);
 125         replay.quiet = !(opts->flags & REBASE_NO_QUIET);
 126         replay.verbose = opts->flags & REBASE_VERBOSE;
 127         replay.reschedule_failed_exec = opts->reschedule_failed_exec;
 128         replay.committer_date_is_author_date =
 129                                         opts->committer_date_is_author_date;
 130         replay.gpg_sign = xstrdup_or_null(opts->gpg_sign_opt);
 131         replay.strategy = opts->strategy;
 132
 133         if (opts->strategy_opts)
 134                 parse_strategy_opts(&replay, opts->strategy_opts);
 135
 136         if (opts->squash_onto) {
 137                 oidcpy(&replay.squash_onto, opts->squash_onto);
 138                 replay.have_squash_onto = 1;
 139         }
 140
 141         return replay;
 142 }
 143
 144 enum action {
 145         ACTION_NONE = 0,
 146         ACTION_CONTINUE,
 147         ACTION_SKIP,
 148         ACTION_ABORT,
 149         ACTION_QUIT,
 150         ACTION_EDIT_TODO,
 151         ACTION_SHOW_CURRENT_PATCH,
 152         ACTION_SHORTEN_OIDS,
 153         ACTION_EXPAND_OIDS,
 154         ACTION_CHECK_TODO_LIST,
 155         ACTION_REARRANGE_SQUASH,
 156         ACTION_ADD_EXEC
 157 };
 158
 159 static const char *action_names[] = { "undefined",
 160                                       "continue",
 161                                       "skip",
 162                                       "abort",
 163                                       "quit",
 164                                       "edit_todo",
 165                                       "show_current_patch" };
 166
 167 static int add_exec_commands(struct string_list *commands)
 168 {
 169         const char *todo_file = rebase_path_todo();
 170         struct todo_list todo_list = TODO_LIST_INIT;
 171         int res;
 172
 173         if (strbuf_read_file(&todo_list.buf, todo_file, 0) < 0)
 174                 return error_errno(_("could not read '%s'."), todo_file);
 175
 176         if (todo_list_parse_insn_buffer(the_repository, todo_list.buf.buf,
 177                                         &todo_list)) {
 178                 todo_list_release(&todo_list);
 179                 return error(_("unusable todo list: '%s'"), todo_file);
 180         }
 181
 182         todo_list_add_exec_commands(&todo_list, commands);
 183         res = todo_list_write_to_file(the_repository, &todo_list,
 184                                       todo_file, NULL, NULL, -1, 0);
 185         todo_list_release(&todo_list);
 186
 187         if (res)
 188                 return error_errno(_("could not write '%s'."), todo_file);
 189         return 0;
 190 }
 191
 192 static int rearrange_squash_in_todo_file(void)
 193 {
 194         const char *todo_file = rebase_path_todo();
 195         struct todo_list todo_list = TODO_LIST_INIT;
 196         int res = 0;
 197
 198         if (strbuf_read_file(&todo_list.buf, todo_file, 0) < 0)
 199                 return error_errno(_("could not read '%s'."), todo_file);
 200         if (todo_list_parse_insn_buffer(the_repository, todo_list.buf.buf,
 201                                         &todo_list)) {
 202                 todo_list_release(&todo_list);
 203                 return error(_("unusable todo list: '%s'"), todo_file);
 204         }
 205
 206         res = todo_list_rearrange_squash(&todo_list);
 207         if (!res)
 208                 res = todo_list_write_to_file(the_repository, &todo_list,
 209                                               todo_file, NULL, NULL, -1, 0);
 210
 211         todo_list_release(&todo_list);
 212
 213         if (res)
 214                 return error_errno(_("could not write '%s'."), todo_file);
 215         return 0;
 216 }
 217
 218 static int transform_todo_file(unsigned flags)
 219 {
 220         const char *todo_file = rebase_path_todo();
 221         struct todo_list todo_list = TODO_LIST_INIT;
 222         int res;
 223
 224         if (strbuf_read_file(&todo_list.buf, todo_file, 0) < 0)
 225                 return error_errno(_("could not read '%s'."), todo_file);
 226
 227         if (todo_list_parse_insn_buffer(the_repository, todo_list.buf.buf,
 228                                         &todo_list)) {
 229                 todo_list_release(&todo_list);
 230                 return error(_("unusable todo list: '%s'"), todo_file);
 231         }
 232
 233         res = todo_list_write_to_file(the_repository, &todo_list, todo_file,
 234                                       NULL, NULL, -1, flags);
 235         todo_list_release(&todo_list);
 236
 237         if (res)
 238                 return error_errno(_("could not write '%s'."), todo_file);
 239         return 0;
 240 }
 241
 242 static int edit_todo_file(unsigned flags)
 243 {
 244         const char *todo_file = rebase_path_todo();
 245         struct todo_list todo_list = TODO_LIST_INIT,
 246                 new_todo = TODO_LIST_INIT;
 247         int res = 0;
 248
 249         if (strbuf_read_file(&todo_list.buf, todo_file, 0) < 0)
 250                 return error_errno(_("could not read '%s'."), todo_file);
 251
 252         strbuf_stripspace(&todo_list.buf, 1);
 253         res = edit_todo_list(the_repository, &todo_list, &new_todo, NULL, NULL, flags);
 254         if (!res && todo_list_write_to_file(the_repository, &new_todo, todo_file,
 255                                             NULL, NULL, -1, flags & ~(TODO_LIST_SHORTEN_IDS)))
 256                 res = error_errno(_("could not write '%s'"), todo_file);
 257
 258         todo_list_release(&todo_list);
 259         todo_list_release(&new_todo);
 260
 261         return res;
 262 }
 263
 264 static int get_revision_ranges(struct commit *upstream, struct commit *onto,
 265                                struct object_id *orig_head, const char **head_hash,
 266                                char **revisions, char **shortrevisions)
 267 {
 268         struct commit *base_rev = upstream ? upstream : onto;
 269         const char *shorthead;
 270
 271         *head_hash = find_unique_abbrev(orig_head, GIT_MAX_HEXSZ);
 272         *revisions = xstrfmt("%s...%s", oid_to_hex(&base_rev->object.oid),
 273                                                    *head_hash);
 274
 275         shorthead = find_unique_abbrev(orig_head, DEFAULT_ABBREV);
 276
 277         if (upstream) {
 278                 const char *shortrev;
 279
 280                 shortrev = find_unique_abbrev(&base_rev->object.oid,
 281                                               DEFAULT_ABBREV);
 282
 283                 *shortrevisions = xstrfmt("%s..%s", shortrev, shorthead);
 284         } else
 285                 *shortrevisions = xstrdup(shorthead);
 286
 287         return 0;
 288 }
 289
 290 static int init_basic_state(struct replay_opts *opts, const char *head_name,
 291                             struct commit *onto, const char *orig_head)
 292 {
 293         FILE *interactive;
 294
 295         if (!is_directory(merge_dir()) && mkdir_in_gitdir(merge_dir()))
 296                 return error_errno(_("could not create temporary %s"), merge_dir());
 297
 298         delete_reflog("REBASE_HEAD");
 299
 300         interactive = fopen(path_interactive(), "w");
 301         if (!interactive)
 302                 return error_errno(_("could not mark as interactive"));
 303         fclose(interactive);
 304
 305         return write_basic_state(opts, head_name, onto, orig_head);
 306 }
 307
 308 static void split_exec_commands(const char *cmd, struct string_list *commands)
 309 {
 310         if (cmd && *cmd) {
 311                 string_list_split(commands, cmd, '\n', -1);
 312
 313                 /* rebase.c adds a new line to cmd after every command,
 314                  * so here the last command is always empty */
 315                 string_list_remove_empty_items(commands, 0);
 316         }
 317 }
 318
 319 static int do_interactive_rebase(struct rebase_options *opts, unsigned flags)
 320 {
 321         int ret;
 322         const char *head_hash = NULL;
 323         char *revisions = NULL, *shortrevisions = NULL;
 324         struct argv_array make_script_args = ARGV_ARRAY_INIT;
 325         struct todo_list todo_list = TODO_LIST_INIT;
 326         struct replay_opts replay = get_replay_opts(opts);
 327         struct string_list commands = STRING_LIST_INIT_DUP;
 328
 329         if (get_revision_ranges(opts->upstream, opts->onto, &opts->orig_head,
 330                                 &head_hash, &revisions, &shortrevisions))
 331                 return -1;
 332
 333         if (init_basic_state(&replay,
 334                              opts->head_name ? opts->head_name : "detached HEAD",
 335                              opts->onto, head_hash)) {
 336                 free(revisions);
 337                 free(shortrevisions);
 338
 339                 return -1;
 340         }
 341
 342         if (!opts->upstream && opts->squash_onto)
 343                 write_file(path_squash_onto(), "%s\n",
 344                            oid_to_hex(opts->squash_onto));
 345
 346         argv_array_pushl(&make_script_args, "", revisions, NULL);
 347         if (opts->restrict_revision)
 348                 argv_array_pushf(&make_script_args, "^%s",
 349                                  oid_to_hex(&opts->restrict_revision->object.oid));
 350
 351         ret = sequencer_make_script(the_repository, &todo_list.buf,
 352                                     make_script_args.argc, make_script_args.argv,
 353                                     flags);
 354
 355         if (ret)
 356                 error(_("could not generate todo list"));
 357         else {
 358                 discard_cache();
 359                 if (todo_list_parse_insn_buffer(the_repository, todo_list.buf.buf,
 360                                                 &todo_list))
 361                         BUG("unusable todo list");
 362
 363                 split_exec_commands(opts->cmd, &commands);
 364                 ret = complete_action(the_repository, &replay, flags,
 365                         shortrevisions, opts->onto_name, opts->onto, head_hash,
 366                         &commands, opts->autosquash, &todo_list);
 367         }
 368
 369         string_list_clear(&commands, 0);
 370         free(revisions);
 371         free(shortrevisions);
 372         todo_list_release(&todo_list);
 373         argv_array_clear(&make_script_args);
 374
 375         return ret;
 376 }
 377
 378 static int run_sequencer_rebase(struct rebase_options *opts,
 379                                   enum action command)
 380 {
 381         unsigned flags = 0;
 382         int abbreviate_commands = 0, ret = 0;
 383
 384         git_config_get_bool("rebase.abbreviatecommands", &abbreviate_commands);
 385
 386         flags |= abbreviate_commands ? TODO_LIST_ABBREVIATE_CMDS : 0;
 387         flags |= opts->rebase_merges ? TODO_LIST_REBASE_MERGES : 0;
 388         flags |= opts->rebase_cousins > 0 ? TODO_LIST_REBASE_COUSINS : 0;
 389         flags |= opts->root_with_onto ? TODO_LIST_ROOT_WITH_ONTO : 0;
 390         flags |= command == ACTION_SHORTEN_OIDS ? TODO_LIST_SHORTEN_IDS : 0;
 391
 392         switch (command) {
 393         case ACTION_NONE: {
 394                 if (!opts->onto && !opts->upstream)
 395                         die(_("a base commit must be provided with --upstream or --onto"));
 396
 397                 ret = do_interactive_rebase(opts, flags);
 398                 break;
 399         }
 400         case ACTION_SKIP: {
 401                 struct string_list merge_rr = STRING_LIST_INIT_DUP;
 402
 403                 rerere_clear(the_repository, &merge_rr);
 404         }
 405                 /* fallthrough */
 406         case ACTION_CONTINUE: {
 407                 struct replay_opts replay_opts = get_replay_opts(opts);
 408
 409                 ret = sequencer_continue(the_repository, &replay_opts);
 410                 break;
 411         }
 412         case ACTION_EDIT_TODO:
 413                 ret = edit_todo_file(flags);
 414                 break;
 415         case ACTION_SHOW_CURRENT_PATCH: {
 416                 struct child_process cmd = CHILD_PROCESS_INIT;
 417
 418                 cmd.git_cmd = 1;
 419                 argv_array_pushl(&cmd.args, "show", "REBASE_HEAD", "--", NULL);
 420                 ret = run_command(&cmd);
 421
 422                 break;
 423         }
 424         case ACTION_SHORTEN_OIDS:
 425         case ACTION_EXPAND_OIDS:
 426                 ret = transform_todo_file(flags);
 427                 break;
 428         case ACTION_CHECK_TODO_LIST:
 429                 ret = check_todo_list_from_file(the_repository);
 430                 break;
 431         case ACTION_REARRANGE_SQUASH:
 432                 ret = rearrange_squash_in_todo_file();
 433                 break;
 434         case ACTION_ADD_EXEC: {
 435                 struct string_list commands = STRING_LIST_INIT_DUP;
 436
 437                 split_exec_commands(opts->cmd, &commands);
 438                 ret = add_exec_commands(&commands);
 439                 string_list_clear(&commands, 0);
 440                 break;
 441         }
 442         default:
 443                 BUG("invalid command '%d'", command);
 444         }
 445
 446         return ret;
 447 }
 448
 449 static int parse_opt_keep_empty(const struct option *opt, const char *arg,
 450                                 int unset)
 451 {
 452         struct rebase_options *opts = opt->value;
 453
 454         BUG_ON_OPT_ARG(arg);
 455
 456         /*
 457          * If we ever want to remap --keep-empty to --empty=keep, insert:
 458          *      opts->empty = unset ? EMPTY_UNSPECIFIED : EMPTY_KEEP;
 459          */
 460         opts->type = REBASE_MERGE;
 461         return 0;
 462 }
 463
 464 static const char * const builtin_rebase_interactive_usage[] = {
 465         N_("git rebase--interactive [<options>]"),
 466         NULL
 467 };
 468
 469 int cmd_rebase__interactive(int argc, const char **argv, const char *prefix)
 470 {
 471         struct rebase_options opts = REBASE_OPTIONS_INIT;
 472         struct object_id squash_onto = null_oid;
 473         enum action command = ACTION_NONE;
 474         struct option options[] = {
 475                 OPT_NEGBIT(0, "ff", &opts.flags, N_("allow fast-forward"),
 476                            REBASE_FORCE),
 477                 { OPTION_CALLBACK, 'k', "keep-empty", &options, NULL,
 478                         N_("(DEPRECATED) keep empty commits"),
 479                         PARSE_OPT_NOARG | PARSE_OPT_HIDDEN,
 480                         parse_opt_keep_empty },
 481                 OPT_BOOL_F(0, "allow-empty-message", &opts.allow_empty_message,
 482                            N_("allow commits with empty messages"),
 483                            PARSE_OPT_HIDDEN),
 484                 OPT_BOOL(0, "rebase-merges", &opts.rebase_merges, N_("rebase merge commits")),
 485                 OPT_BOOL(0, "rebase-cousins", &opts.rebase_cousins,
 486                          N_("keep original branch points of cousins")),
 487                 OPT_BOOL(0, "autosquash", &opts.autosquash,
 488                          N_("move commits that begin with squash!/fixup!")),
 489                 OPT_BOOL(0, "signoff", &opts.signoff, N_("sign commits")),
 490                 OPT_BIT('v', "verbose", &opts.flags,
 491                         N_("display a diffstat of what changed upstream"),
 492                         REBASE_NO_QUIET | REBASE_VERBOSE | REBASE_DIFFSTAT),
 493                 OPT_CMDMODE(0, "continue", &command, N_("continue rebase"),
 494                             ACTION_CONTINUE),
 495                 OPT_CMDMODE(0, "skip", &command, N_("skip commit"), ACTION_SKIP),
 496                 OPT_CMDMODE(0, "edit-todo", &command, N_("edit the todo list"),
 497                             ACTION_EDIT_TODO),
 498                 OPT_CMDMODE(0, "show-current-patch", &command, N_("show the current patch"),
 499                             ACTION_SHOW_CURRENT_PATCH),
 500                 OPT_CMDMODE(0, "shorten-ids", &command,
 501                         N_("shorten commit ids in the todo list"), ACTION_SHORTEN_OIDS),
 502                 OPT_CMDMODE(0, "expand-ids", &command,
 503                         N_("expand commit ids in the todo list"), ACTION_EXPAND_OIDS),
 504                 OPT_CMDMODE(0, "check-todo-list", &command,
 505                         N_("check the todo list"), ACTION_CHECK_TODO_LIST),
 506                 OPT_CMDMODE(0, "rearrange-squash", &command,
 507                         N_("rearrange fixup/squash lines"), ACTION_REARRANGE_SQUASH),
 508                 OPT_CMDMODE(0, "add-exec-commands", &command,
 509                         N_("insert exec commands in todo list"), ACTION_ADD_EXEC),
 510                 { OPTION_CALLBACK, 0, "onto", &opts.onto, N_("onto"), N_("onto"),
 511                   PARSE_OPT_NONEG, parse_opt_commit, 0 },
 512                 { OPTION_CALLBACK, 0, "restrict-revision", &opts.restrict_revision,
 513                   N_("restrict-revision"), N_("restrict revision"),
 514                   PARSE_OPT_NONEG, parse_opt_commit, 0 },
 515                 { OPTION_CALLBACK, 0, "squash-onto", &squash_onto, N_("squash-onto"),
 516                   N_("squash onto"), PARSE_OPT_NONEG, parse_opt_object_id, 0 },
 517                 { OPTION_CALLBACK, 0, "upstream", &opts.upstream, N_("upstream"),
 518                   N_("the upstream commit"), PARSE_OPT_NONEG, parse_opt_commit,
 519                   0 },
 520                 OPT_STRING(0, "head-name", &opts.head_name, N_("head-name"), N_("head name")),
 521                 { OPTION_STRING, 'S', "gpg-sign", &opts.gpg_sign_opt, N_("key-id"),
 522                         N_("GPG-sign commits"),
 523                         PARSE_OPT_OPTARG, NULL, (intptr_t) "" },
 524                 OPT_STRING(0, "strategy", &opts.strategy, N_("strategy"),
 525                            N_("rebase strategy")),
 526                 OPT_STRING(0, "strategy-opts", &opts.strategy_opts, N_("strategy-opts"),
 527                            N_("strategy options")),
 528                 OPT_STRING(0, "switch-to", &opts.switch_to, N_("switch-to"),
 529                            N_("the branch or commit to checkout")),
 530                 OPT_STRING(0, "onto-name", &opts.onto_name, N_("onto-name"), N_("onto name")),
 531                 OPT_STRING(0, "cmd", &opts.cmd, N_("cmd"), N_("the command to run")),
 532                 OPT_RERERE_AUTOUPDATE(&opts.allow_rerere_autoupdate),
 533                 OPT_BOOL(0, "reschedule-failed-exec", &opts.reschedule_failed_exec,
 534                          N_("automatically re-schedule any `exec` that fails")),
 535                 OPT_END()
 536         };
 537
 538         opts.rebase_cousins = -1;
 539
 540         if (argc == 1)
 541                 usage_with_options(builtin_rebase_interactive_usage, options);
 542
 543         argc = parse_options(argc, argv, prefix, options,
 544                         builtin_rebase_interactive_usage, PARSE_OPT_KEEP_ARGV0);
 545
 546         if (!is_null_oid(&squash_onto))
 547                 opts.squash_onto = &squash_onto;
 548
 549         if (opts.rebase_cousins >= 0 && !opts.rebase_merges)
 550                 warning(_("--[no-]rebase-cousins has no effect without "
 551                           "--rebase-merges"));
 552
 553         return !!run_sequencer_rebase(&opts, command);
 554 }
 555
 556 static int is_merge(struct rebase_options *opts)
 557 {
 558         return opts->type == REBASE_MERGE ||
 559                 opts->type == REBASE_PRESERVE_MERGES;
 560 }
 561
 562 static void imply_merge(struct rebase_options *opts, const char *option)
 563 {
 564         switch (opts->type) {
 565         case REBASE_APPLY:
 566                 die(_("%s requires an interactive rebase"), option);
 567                 break;
 568         case REBASE_MERGE:
 569         case REBASE_PRESERVE_MERGES:
 570                 break;
 571         default:
 572                 opts->type = REBASE_MERGE; /* implied */
 573                 break;
 574         }
 575 }
 576
 577 /* Returns the filename prefixed by the state_dir */
 578 static const char *state_dir_path(const char *filename, struct rebase_options *opts)
 579 {
 580         static struct strbuf path = STRBUF_INIT;
 581         static size_t prefix_len;
 582
 583         if (!prefix_len) {
 584                 strbuf_addf(&path, "%s/", opts->state_dir);
 585                 prefix_len = path.len;
 586         }
 587
 588         strbuf_setlen(&path, prefix_len);
 589         strbuf_addstr(&path, filename);
 590         return path.buf;
 591 }
 592
 593 /* Read one file, then strip line endings */
 594 static int read_one(const char *path, struct strbuf *buf)
 595 {
 596         if (strbuf_read_file(buf, path, 0) < 0)
 597                 return error_errno(_("could not read '%s'"), path);
 598         strbuf_trim_trailing_newline(buf);
 599         return 0;
 600 }
 601
 602 /* Initialize the rebase options from the state directory. */
 603 static int read_basic_state(struct rebase_options *opts)
 604 {
 605         struct strbuf head_name = STRBUF_INIT;
 606         struct strbuf buf = STRBUF_INIT;
 607         struct object_id oid;
 608
 609         if (read_one(state_dir_path("head-name", opts), &head_name) ||
 610             read_one(state_dir_path("onto", opts), &buf))
 611                 return -1;
 612         opts->head_name = starts_with(head_name.buf, "refs/") ?
 613                 xstrdup(head_name.buf) : NULL;
 614         strbuf_release(&head_name);
 615         if (get_oid(buf.buf, &oid))
 616                 return error(_("could not get 'onto': '%s'"), buf.buf);
 617         opts->onto = lookup_commit_or_die(&oid, buf.buf);
 618
 619         /*
 620          * We always write to orig-head, but interactive rebase used to write to
 621          * head. Fall back to reading from head to cover for the case that the
 622          * user upgraded git with an ongoing interactive rebase.
 623          */
 624         strbuf_reset(&buf);
 625         if (file_exists(state_dir_path("orig-head", opts))) {
 626                 if (read_one(state_dir_path("orig-head", opts), &buf))
 627                         return -1;
 628         } else if (read_one(state_dir_path("head", opts), &buf))
 629                 return -1;
 630         if (get_oid(buf.buf, &opts->orig_head))
 631                 return error(_("invalid orig-head: '%s'"), buf.buf);
 632
 633         if (file_exists(state_dir_path("quiet", opts)))
 634                 opts->flags &= ~REBASE_NO_QUIET;
 635         else
 636                 opts->flags |= REBASE_NO_QUIET;
 637
 638         if (file_exists(state_dir_path("verbose", opts)))
 639                 opts->flags |= REBASE_VERBOSE;
 640
 641         if (file_exists(state_dir_path("signoff", opts))) {
 642                 opts->signoff = 1;
 643                 opts->flags |= REBASE_FORCE;
 644         }
 645
 646         if (file_exists(state_dir_path("allow_rerere_autoupdate", opts))) {
 647                 strbuf_reset(&buf);
 648                 if (read_one(state_dir_path("allow_rerere_autoupdate", opts),
 649                             &buf))
 650                         return -1;
 651                 if (!strcmp(buf.buf, "--rerere-autoupdate"))
 652                         opts->allow_rerere_autoupdate = RERERE_AUTOUPDATE;
 653                 else if (!strcmp(buf.buf, "--no-rerere-autoupdate"))
 654                         opts->allow_rerere_autoupdate = RERERE_NOAUTOUPDATE;
 655                 else
 656                         warning(_("ignoring invalid allow_rerere_autoupdate: "
 657                                   "'%s'"), buf.buf);
 658         }
 659
 660         if (file_exists(state_dir_path("gpg_sign_opt", opts))) {
 661                 strbuf_reset(&buf);
 662                 if (read_one(state_dir_path("gpg_sign_opt", opts),
 663                             &buf))
 664                         return -1;
 665                 free(opts->gpg_sign_opt);
 666                 opts->gpg_sign_opt = xstrdup(buf.buf);
 667         }
 668
 669         if (file_exists(state_dir_path("strategy", opts))) {
 670                 strbuf_reset(&buf);
 671                 if (read_one(state_dir_path("strategy", opts), &buf))
 672                         return -1;
 673                 free(opts->strategy);
 674                 opts->strategy = xstrdup(buf.buf);
 675         }
 676
 677         if (file_exists(state_dir_path("strategy_opts", opts))) {
 678                 strbuf_reset(&buf);
 679                 if (read_one(state_dir_path("strategy_opts", opts), &buf))
 680                         return -1;
 681                 free(opts->strategy_opts);
 682                 opts->strategy_opts = xstrdup(buf.buf);
 683         }
 684
 685         strbuf_release(&buf);
 686
 687         return 0;
 688 }
 689
 690 static int rebase_write_basic_state(struct rebase_options *opts)
 691 {
 692         write_file(state_dir_path("head-name", opts), "%s",
 693                    opts->head_name ? opts->head_name : "detached HEAD");
 694         write_file(state_dir_path("onto", opts), "%s",
 695                    opts->onto ? oid_to_hex(&opts->onto->object.oid) : "");
 696         write_file(state_dir_path("orig-head", opts), "%s",
 697                    oid_to_hex(&opts->orig_head));
 698         if (!(opts->flags & REBASE_NO_QUIET))
 699                 write_file(state_dir_path("quiet", opts), "%s", "");
 700         if (opts->flags & REBASE_VERBOSE)
 701                 write_file(state_dir_path("verbose", opts), "%s", "");
 702         if (opts->strategy)
 703                 write_file(state_dir_path("strategy", opts), "%s",
 704                            opts->strategy);
 705         if (opts->strategy_opts)
 706                 write_file(state_dir_path("strategy_opts", opts), "%s",
 707                            opts->strategy_opts);
 708         if (opts->allow_rerere_autoupdate > 0)
 709                 write_file(state_dir_path("allow_rerere_autoupdate", opts),
 710                            "-%s-rerere-autoupdate",
 711                            opts->allow_rerere_autoupdate == RERERE_AUTOUPDATE ?
 712                                 "" : "-no");
 713         if (opts->gpg_sign_opt)
 714                 write_file(state_dir_path("gpg_sign_opt", opts), "%s",
 715                            opts->gpg_sign_opt);
 716         if (opts->signoff)
 717                 write_file(state_dir_path("signoff", opts), "--signoff");
 718
 719         return 0;
 720 }
 721
 722 static int apply_autostash(struct rebase_options *opts)
 723 {
 724         const char *path = state_dir_path("autostash", opts);
 725         struct strbuf autostash = STRBUF_INIT;
 726         struct child_process stash_apply = CHILD_PROCESS_INIT;
 727
 728         if (!file_exists(path))
 729                 return 0;
 730
 731         if (read_one(path, &autostash))
 732                 return error(_("Could not read '%s'"), path);
 733         /* Ensure that the hash is not mistaken for a number */
 734         strbuf_addstr(&autostash, "^0");
 735         argv_array_pushl(&stash_apply.args,
 736                          "stash", "apply", autostash.buf, NULL);
 737         stash_apply.git_cmd = 1;
 738         stash_apply.no_stderr = stash_apply.no_stdout =
 739                 stash_apply.no_stdin = 1;
 740         if (!run_command(&stash_apply))
 741                 printf(_("Applied autostash.\n"));
 742         else {
 743                 struct argv_array args = ARGV_ARRAY_INIT;
 744                 int res = 0;
 745
 746                 argv_array_pushl(&args,
 747                                  "stash", "store", "-m", "autostash", "-q",
 748                                  autostash.buf, NULL);
 749                 if (run_command_v_opt(args.argv, RUN_GIT_CMD))
 750                         res = error(_("Cannot store %s"), autostash.buf);
 751                 argv_array_clear(&args);
 752                 strbuf_release(&autostash);
 753                 if (res)
 754                         return res;
 755
 756                 fprintf(stderr,
 757                         _("Applying autostash resulted in conflicts.\n"
 758                           "Your changes are safe in the stash.\n"
 759                           "You can run \"git stash pop\" or \"git stash drop\" "
 760                           "at any time.\n"));
 761         }
 762
 763         strbuf_release(&autostash);
 764         return 0;
 765 }
 766
 767 static int finish_rebase(struct rebase_options *opts)
 768 {
 769         struct strbuf dir = STRBUF_INIT;
 770         const char *argv_gc_auto[] = { "gc", "--auto", NULL };
 771         int ret = 0;
 772
 773         delete_ref(NULL, "REBASE_HEAD", NULL, REF_NO_DEREF);
 774         apply_autostash(opts);
 775         close_object_store(the_repository->objects);
 776         /*
 777          * We ignore errors in 'gc --auto', since the
 778          * user should see them.
 779          */
 780         run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
 781         if (opts->type == REBASE_MERGE) {
 782                 struct replay_opts replay = REPLAY_OPTS_INIT;
 783
 784                 replay.action = REPLAY_INTERACTIVE_REBASE;
 785                 ret = sequencer_remove_state(&replay);
 786         } else {
 787                 strbuf_addstr(&dir, opts->state_dir);
 788                 if (remove_dir_recursively(&dir, 0))
 789                         ret = error(_("could not remove '%s'"),
 790                                     opts->state_dir);
 791                 strbuf_release(&dir);
 792         }
 793
 794         return ret;
 795 }
 796
 797 static struct commit *peel_committish(const char *name)
 798 {
 799         struct object *obj;
 800         struct object_id oid;
 801
 802         if (get_oid(name, &oid))
 803                 return NULL;
 804         obj = parse_object(the_repository, &oid);
 805         return (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
 806 }
 807
 808 static void add_var(struct strbuf *buf, const char *name, const char *value)
 809 {
 810         if (!value)
 811                 strbuf_addf(buf, "unset %s; ", name);
 812         else {
 813                 strbuf_addf(buf, "%s=", name);
 814                 sq_quote_buf(buf, value);
 815                 strbuf_addstr(buf, "; ");
 816         }
 817 }
 818
 819 #define GIT_REFLOG_ACTION_ENVIRONMENT "GIT_REFLOG_ACTION"
 820
 821 #define RESET_HEAD_DETACH (1<<0)
 822 #define RESET_HEAD_HARD (1<<1)
 823 #define RESET_HEAD_RUN_POST_CHECKOUT_HOOK (1<<2)
 824 #define RESET_HEAD_REFS_ONLY (1<<3)
 825 #define RESET_ORIG_HEAD (1<<4)
 826
 827 static int reset_head(struct object_id *oid, const char *action,
 828                       const char *switch_to_branch, unsigned flags,
 829                       const char *reflog_orig_head, const char *reflog_head)
 830 {
 831         unsigned detach_head = flags & RESET_HEAD_DETACH;
 832         unsigned reset_hard = flags & RESET_HEAD_HARD;
 833         unsigned run_hook = flags & RESET_HEAD_RUN_POST_CHECKOUT_HOOK;
 834         unsigned refs_only = flags & RESET_HEAD_REFS_ONLY;
 835         unsigned update_orig_head = flags & RESET_ORIG_HEAD;
 836         struct object_id head_oid;
 837         struct tree_desc desc[2] = { { NULL }, { NULL } };
 838         struct lock_file lock = LOCK_INIT;
 839         struct unpack_trees_options unpack_tree_opts;
 840         struct tree *tree;
 841         const char *reflog_action;
 842         struct strbuf msg = STRBUF_INIT;
 843         size_t prefix_len;
 844         struct object_id *orig = NULL, oid_orig,
 845                 *old_orig = NULL, oid_old_orig;
 846         int ret = 0, nr = 0;
 847
 848         if (switch_to_branch && !starts_with(switch_to_branch, "refs/"))
 849                 BUG("Not a fully qualified branch: '%s'", switch_to_branch);
 850
 851         if (!refs_only && hold_locked_index(&lock, LOCK_REPORT_ON_ERROR) < 0) {
 852                 ret = -1;
 853                 goto leave_reset_head;
 854         }
 855
 856         if ((!oid || !reset_hard) && get_oid("HEAD", &head_oid)) {
 857                 ret = error(_("could not determine HEAD revision"));
 858                 goto leave_reset_head;
 859         }
 860
 861         if (!oid)
 862                 oid = &head_oid;
 863
 864         if (refs_only)
 865                 goto reset_head_refs;
 866
 867         memset(&unpack_tree_opts, 0, sizeof(unpack_tree_opts));
 868         setup_unpack_trees_porcelain(&unpack_tree_opts, action);
 869         unpack_tree_opts.head_idx = 1;
 870         unpack_tree_opts.src_index = the_repository->index;
 871         unpack_tree_opts.dst_index = the_repository->index;
 872         unpack_tree_opts.fn = reset_hard ? oneway_merge : twoway_merge;
 873         unpack_tree_opts.update = 1;
 874         unpack_tree_opts.merge = 1;
 875         init_checkout_metadata(&unpack_tree_opts.meta, switch_to_branch, oid, NULL);
 876         if (!detach_head)
 877                 unpack_tree_opts.reset = 1;
 878
 879         if (repo_read_index_unmerged(the_repository) < 0) {
 880                 ret = error(_("could not read index"));
 881                 goto leave_reset_head;
 882         }
 883
 884         if (!reset_hard && !fill_tree_descriptor(the_repository, &desc[nr++], &head_oid)) {
 885                 ret = error(_("failed to find tree of %s"),
 886                             oid_to_hex(&head_oid));
 887                 goto leave_reset_head;
 888         }
 889
 890         if (!fill_tree_descriptor(the_repository, &desc[nr++], oid)) {
 891                 ret = error(_("failed to find tree of %s"), oid_to_hex(oid));
 892                 goto leave_reset_head;
 893         }
 894
 895         if (unpack_trees(nr, desc, &unpack_tree_opts)) {
 896                 ret = -1;
 897                 goto leave_reset_head;
 898         }
 899
 900         tree = parse_tree_indirect(oid);
 901         prime_cache_tree(the_repository, the_repository->index, tree);
 902
 903         if (write_locked_index(the_repository->index, &lock, COMMIT_LOCK) < 0) {
 904                 ret = error(_("could not write index"));
 905                 goto leave_reset_head;
 906         }
 907
 908 reset_head_refs:
 909         reflog_action = getenv(GIT_REFLOG_ACTION_ENVIRONMENT);
 910         strbuf_addf(&msg, "%s: ", reflog_action ? reflog_action : "rebase");
 911         prefix_len = msg.len;
 912
 913         if (update_orig_head) {
 914                 if (!get_oid("ORIG_HEAD", &oid_old_orig))
 915                         old_orig = &oid_old_orig;
 916                 if (!get_oid("HEAD", &oid_orig)) {
 917                         orig = &oid_orig;
 918                         if (!reflog_orig_head) {
 919                                 strbuf_addstr(&msg, "updating ORIG_HEAD");
 920                                 reflog_orig_head = msg.buf;
 921                         }
 922                         update_ref(reflog_orig_head, "ORIG_HEAD", orig,
 923                                    old_orig, 0, UPDATE_REFS_MSG_ON_ERR);
 924                 } else if (old_orig)
 925                         delete_ref(NULL, "ORIG_HEAD", old_orig, 0);
 926         }
 927
 928         if (!reflog_head) {
 929                 strbuf_setlen(&msg, prefix_len);
 930                 strbuf_addstr(&msg, "updating HEAD");
 931                 reflog_head = msg.buf;
 932         }
 933         if (!switch_to_branch)
 934                 ret = update_ref(reflog_head, "HEAD", oid, orig,
 935                                  detach_head ? REF_NO_DEREF : 0,
 936                                  UPDATE_REFS_MSG_ON_ERR);
 937         else {
 938                 ret = update_ref(reflog_head, switch_to_branch, oid,
 939                                  NULL, 0, UPDATE_REFS_MSG_ON_ERR);
 940                 if (!ret)
 941                         ret = create_symref("HEAD", switch_to_branch,
 942                                             reflog_head);
 943         }
 944         if (run_hook)
 945                 run_hook_le(NULL, "post-checkout",
 946                             oid_to_hex(orig ? orig : &null_oid),
 947                             oid_to_hex(oid), "1", NULL);
 948
 949 leave_reset_head:
 950         strbuf_release(&msg);
 951         rollback_lock_file(&lock);
 952         while (nr)
 953                 free((void *)desc[--nr].buffer);
 954         return ret;
 955 }
 956
 957 static int move_to_original_branch(struct rebase_options *opts)
 958 {
 959         struct strbuf orig_head_reflog = STRBUF_INIT, head_reflog = STRBUF_INIT;
 960         int ret;
 961
 962         if (!opts->head_name)
 963                 return 0; /* nothing to move back to */
 964
 965         if (!opts->onto)
 966                 BUG("move_to_original_branch without onto");
 967
 968         strbuf_addf(&orig_head_reflog, "rebase finished: %s onto %s",
 969                     opts->head_name, oid_to_hex(&opts->onto->object.oid));
 970         strbuf_addf(&head_reflog, "rebase finished: returning to %s",
 971                     opts->head_name);
 972         ret = reset_head(NULL, "", opts->head_name, RESET_HEAD_REFS_ONLY,
 973                          orig_head_reflog.buf, head_reflog.buf);
 974
 975         strbuf_release(&orig_head_reflog);
 976         strbuf_release(&head_reflog);
 977         return ret;
 978 }
 979
 980 static const char *resolvemsg =
 981 N_("Resolve all conflicts manually, mark them as resolved with\n"
 982 "\"git add/rm <conflicted_files>\", then run \"git rebase --continue\".\n"
 983 "You can instead skip this commit: run \"git rebase --skip\".\n"
 984 "To abort and get back to the state before \"git rebase\", run "
 985 "\"git rebase --abort\".");
 986
 987 static int run_am(struct rebase_options *opts)
 988 {
 989         struct child_process am = CHILD_PROCESS_INIT;
 990         struct child_process format_patch = CHILD_PROCESS_INIT;
 991         struct strbuf revisions = STRBUF_INIT;
 992         int status;
 993         char *rebased_patches;
 994
 995         am.git_cmd = 1;
 996         argv_array_push(&am.args, "am");
 997
 998         if (opts->action && !strcmp("continue", opts->action)) {
 999                 argv_array_push(&am.args, "--resolved");
1000                 argv_array_pushf(&am.args, "--resolvemsg=%s", resolvemsg);
1001                 if (opts->gpg_sign_opt)
1002                         argv_array_push(&am.args, opts->gpg_sign_opt);
1003                 status = run_command(&am);
1004                 if (status)
1005                         return status;
1006
1007                 return move_to_original_branch(opts);
1008         }
1009         if (opts->action && !strcmp("skip", opts->action)) {
1010                 argv_array_push(&am.args, "--skip");
1011                 argv_array_pushf(&am.args, "--resolvemsg=%s", resolvemsg);
1012                 status = run_command(&am);
1013                 if (status)
1014                         return status;
1015
1016                 return move_to_original_branch(opts);
1017         }
1018         if (opts->action && !strcmp("show-current-patch", opts->action)) {
1019                 argv_array_push(&am.args, "--show-current-patch");
1020                 return run_command(&am);
1021         }
1022
1023         strbuf_addf(&revisions, "%s...%s",
1024                     oid_to_hex(opts->root ?
1025                                /* this is now equivalent to !opts->upstream */
1026                                &opts->onto->object.oid :
1027                                &opts->upstream->object.oid),
1028                     oid_to_hex(&opts->orig_head));
1029
1030         rebased_patches = xstrdup(git_path("rebased-patches"));
1031         format_patch.out = open(rebased_patches,
1032                                 O_WRONLY | O_CREAT | O_TRUNC, 0666);
1033         if (format_patch.out < 0) {
1034                 status = error_errno(_("could not open '%s' for writing"),
1035                                      rebased_patches);
1036                 free(rebased_patches);
1037                 argv_array_clear(&am.args);
1038                 return status;
1039         }
1040
1041         format_patch.git_cmd = 1;
1042         argv_array_pushl(&format_patch.args, "format-patch", "-k", "--stdout",
1043                          "--full-index", "--cherry-pick", "--right-only",
1044                          "--src-prefix=a/", "--dst-prefix=b/", "--no-renames",
1045                          "--no-cover-letter", "--pretty=mboxrd", "--topo-order",
1046                          "--no-base", NULL);
1047         if (opts->git_format_patch_opt.len)
1048                 argv_array_split(&format_patch.args,
1049                                  opts->git_format_patch_opt.buf);
1050         argv_array_push(&format_patch.args, revisions.buf);
1051         if (opts->restrict_revision)
1052                 argv_array_pushf(&format_patch.args, "^%s",
1053                                  oid_to_hex(&opts->restrict_revision->object.oid));
1054
1055         status = run_command(&format_patch);
1056         if (status) {
1057                 unlink(rebased_patches);
1058                 free(rebased_patches);
1059                 argv_array_clear(&am.args);
1060
1061                 reset_head(&opts->orig_head, "checkout", opts->head_name, 0,
1062                            "HEAD", NULL);
1063                 error(_("\ngit encountered an error while preparing the "
1064                         "patches to replay\n"
1065                         "these revisions:\n"
1066                         "\n    %s\n\n"
1067                         "As a result, git cannot rebase them."),
1068                       opts->revisions);
1069
1070                 strbuf_release(&revisions);
1071                 return status;
1072         }
1073         strbuf_release(&revisions);
1074
1075         am.in = open(rebased_patches, O_RDONLY);
1076         if (am.in < 0) {
1077                 status = error_errno(_("could not open '%s' for reading"),
1078                                      rebased_patches);
1079                 free(rebased_patches);
1080                 argv_array_clear(&am.args);
1081                 return status;
1082         }
1083
1084         argv_array_pushv(&am.args, opts->git_am_opts.argv);
1085         argv_array_push(&am.args, "--rebasing");
1086         argv_array_pushf(&am.args, "--resolvemsg=%s", resolvemsg);
1087         argv_array_push(&am.args, "--patch-format=mboxrd");
1088         if (opts->allow_rerere_autoupdate == RERERE_AUTOUPDATE)
1089                 argv_array_push(&am.args, "--rerere-autoupdate");
1090         else if (opts->allow_rerere_autoupdate == RERERE_NOAUTOUPDATE)
1091                 argv_array_push(&am.args, "--no-rerere-autoupdate");
1092         if (opts->gpg_sign_opt)
1093                 argv_array_push(&am.args, opts->gpg_sign_opt);
1094         status = run_command(&am);
1095         unlink(rebased_patches);
1096         free(rebased_patches);
1097
1098         if (!status) {
1099                 return move_to_original_branch(opts);
1100         }
1101
1102         if (is_directory(opts->state_dir))
1103                 rebase_write_basic_state(opts);
1104
1105         return status;
1106 }
1107
1108 static int run_specific_rebase(struct rebase_options *opts, enum action action)
1109 {
1110         const char *argv[] = { NULL, NULL };
1111         struct strbuf script_snippet = STRBUF_INIT, buf = STRBUF_INIT;
1112         int status;
1113         const char *backend, *backend_func;
1114
1115         if (opts->type == REBASE_MERGE) {
1116                 /* Run sequencer-based rebase */
1117                 setenv("GIT_CHERRY_PICK_HELP", resolvemsg, 1);
1118                 if (!(opts->flags & REBASE_INTERACTIVE_EXPLICIT)) {
1119                         setenv("GIT_SEQUENCE_EDITOR", ":", 1);
1120                         opts->autosquash = 0;
1121                 }
1122                 if (opts->gpg_sign_opt) {
1123                         /* remove the leading "-S" */
1124                         char *tmp = xstrdup(opts->gpg_sign_opt + 2);
1125                         free(opts->gpg_sign_opt);
1126                         opts->gpg_sign_opt = tmp;
1127                 }
1128
1129                 status = run_sequencer_rebase(opts, action);
1130                 goto finished_rebase;
1131         }
1132
1133         if (opts->type == REBASE_APPLY) {
1134                 status = run_am(opts);
1135                 goto finished_rebase;
1136         }
1137
1138         add_var(&script_snippet, "GIT_DIR", absolute_path(get_git_dir()));
1139         add_var(&script_snippet, "state_dir", opts->state_dir);
1140
1141         add_var(&script_snippet, "upstream_name", opts->upstream_name);
1142         add_var(&script_snippet, "upstream", opts->upstream ?
1143                 oid_to_hex(&opts->upstream->object.oid) : NULL);
1144         add_var(&script_snippet, "head_name",
1145                 opts->head_name ? opts->head_name : "detached HEAD");
1146         add_var(&script_snippet, "orig_head", oid_to_hex(&opts->orig_head));
1147         add_var(&script_snippet, "onto", opts->onto ?
1148                 oid_to_hex(&opts->onto->object.oid) : NULL);
1149         add_var(&script_snippet, "onto_name", opts->onto_name);
1150         add_var(&script_snippet, "revisions", opts->revisions);
1151         add_var(&script_snippet, "restrict_revision", opts->restrict_revision ?
1152                 oid_to_hex(&opts->restrict_revision->object.oid) : NULL);
1153         sq_quote_argv_pretty(&buf, opts->git_am_opts.argv);
1154         add_var(&script_snippet, "git_am_opt", buf.buf);
1155         strbuf_release(&buf);
1156         add_var(&script_snippet, "verbose",
1157                 opts->flags & REBASE_VERBOSE ? "t" : "");
1158         add_var(&script_snippet, "diffstat",
1159                 opts->flags & REBASE_DIFFSTAT ? "t" : "");
1160         add_var(&script_snippet, "force_rebase",
1161                 opts->flags & REBASE_FORCE ? "t" : "");
1162         if (opts->switch_to)
1163                 add_var(&script_snippet, "switch_to", opts->switch_to);
1164         add_var(&script_snippet, "action", opts->action ? opts->action : "");
1165         add_var(&script_snippet, "signoff", opts->signoff ? "--signoff" : "");
1166         add_var(&script_snippet, "allow_rerere_autoupdate",
1167                 opts->allow_rerere_autoupdate ?
1168                         opts->allow_rerere_autoupdate == RERERE_AUTOUPDATE ?
1169                         "--rerere-autoupdate" : "--no-rerere-autoupdate" : "");
1170         add_var(&script_snippet, "autosquash", opts->autosquash ? "t" : "");
1171         add_var(&script_snippet, "gpg_sign_opt", opts->gpg_sign_opt);
1172         add_var(&script_snippet, "cmd", opts->cmd);
1173         add_var(&script_snippet, "allow_empty_message",
1174                 opts->allow_empty_message ?  "--allow-empty-message" : "");
1175         add_var(&script_snippet, "rebase_merges",
1176                 opts->rebase_merges ? "t" : "");
1177         add_var(&script_snippet, "rebase_cousins",
1178                 opts->rebase_cousins ? "t" : "");
1179         add_var(&script_snippet, "strategy", opts->strategy);
1180         add_var(&script_snippet, "strategy_opts", opts->strategy_opts);
1181         add_var(&script_snippet, "rebase_root", opts->root ? "t" : "");
1182         add_var(&script_snippet, "squash_onto",
1183                 opts->squash_onto ? oid_to_hex(opts->squash_onto) : "");
1184         add_var(&script_snippet, "git_format_patch_opt",
1185                 opts->git_format_patch_opt.buf);
1186
1187         if (is_merge(opts) &&
1188             !(opts->flags & REBASE_INTERACTIVE_EXPLICIT)) {
1189                 strbuf_addstr(&script_snippet,
1190                               "GIT_SEQUENCE_EDITOR=:; export GIT_SEQUENCE_EDITOR; ");
1191                 opts->autosquash = 0;
1192         }
1193
1194         switch (opts->type) {
1195         case REBASE_PRESERVE_MERGES:
1196                 backend = "git-rebase--preserve-merges";
1197                 backend_func = "git_rebase__preserve_merges";
1198                 break;
1199         default:
1200                 BUG("Unhandled rebase type %d", opts->type);
1201                 break;
1202         }
1203
1204         strbuf_addf(&script_snippet,
1205                     ". git-sh-setup && . %s && %s", backend, backend_func);
1206         argv[0] = script_snippet.buf;
1207
1208         status = run_command_v_opt(argv, RUN_USING_SHELL);
1209 finished_rebase:
1210         if (opts->dont_finish_rebase)
1211                 ; /* do nothing */
1212         else if (opts->type == REBASE_MERGE)
1213                 ; /* merge backend cleans up after itself */
1214         else if (status == 0) {
1215                 if (!file_exists(state_dir_path("stopped-sha", opts)))
1216                         finish_rebase(opts);
1217         } else if (status == 2) {
1218                 struct strbuf dir = STRBUF_INIT;
1219
1220                 apply_autostash(opts);
1221                 strbuf_addstr(&dir, opts->state_dir);
1222                 remove_dir_recursively(&dir, 0);
1223                 strbuf_release(&dir);
1224                 die("Nothing to do");
1225         }
1226
1227         strbuf_release(&script_snippet);
1228
1229         return status ? -1 : 0;
1230 }
1231
1232 static int rebase_config(const char *var, const char *value, void *data)
1233 {
1234         struct rebase_options *opts = data;
1235
1236         if (!strcmp(var, "rebase.stat")) {
1237                 if (git_config_bool(var, value))
1238                         opts->flags |= REBASE_DIFFSTAT;
1239                 else
1240                         opts->flags &= ~REBASE_DIFFSTAT;
1241                 return 0;
1242         }
1243
1244         if (!strcmp(var, "rebase.autosquash")) {
1245                 opts->autosquash = git_config_bool(var, value);
1246                 return 0;
1247         }
1248
1249         if (!strcmp(var, "commit.gpgsign")) {
1250                 free(opts->gpg_sign_opt);
1251                 opts->gpg_sign_opt = git_config_bool(var, value) ?
1252                         xstrdup("-S") : NULL;
1253                 return 0;
1254         }
1255
1256         if (!strcmp(var, "rebase.autostash")) {
1257                 opts->autostash = git_config_bool(var, value);
1258                 return 0;
1259         }
1260
1261         if (!strcmp(var, "rebase.reschedulefailedexec")) {
1262                 opts->reschedule_failed_exec = git_config_bool(var, value);
1263                 return 0;
1264         }
1265
1266         if (!strcmp(var, "rebase.usebuiltin")) {
1267                 opts->use_legacy_rebase = !git_config_bool(var, value);
1268                 return 0;
1269         }
1270
1271         if (!strcmp(var, "rebase.backend")) {
1272                 return git_config_string(&opts->default_backend, var, value);
1273         }
1274
1275         return git_default_config(var, value, data);
1276 }
1277
1278 /*
1279  * Determines whether the commits in from..to are linear, i.e. contain
1280  * no merge commits. This function *expects* `from` to be an ancestor of
1281  * `to`.
1282  */
1283 static int is_linear_history(struct commit *from, struct commit *to)
1284 {
1285         while (to && to != from) {
1286                 parse_commit(to);
1287                 if (!to->parents)
1288                         return 1;
1289                 if (to->parents->next)
1290                         return 0;
1291                 to = to->parents->item;
1292         }
1293         return 1;
1294 }
1295
1296 static int can_fast_forward(struct commit *onto, struct commit *upstream,
1297                             struct commit *restrict_revision,
1298                             struct object_id *head_oid, struct object_id *merge_base)
1299 {
1300         struct commit *head = lookup_commit(the_repository, head_oid);
1301         struct commit_list *merge_bases = NULL;
1302         int res = 0;
1303
1304         if (!head)
1305                 goto done;
1306
1307         merge_bases = get_merge_bases(onto, head);
1308         if (!merge_bases || merge_bases->next) {
1309                 oidcpy(merge_base, &null_oid);
1310                 goto done;
1311         }
1312
1313         oidcpy(merge_base, &merge_bases->item->object.oid);
1314         if (!oideq(merge_base, &onto->object.oid))
1315                 goto done;
1316
1317         if (restrict_revision && !oideq(&restrict_revision->object.oid, merge_base))
1318                 goto done;
1319
1320         if (!upstream)
1321                 goto done;
1322
1323         free_commit_list(merge_bases);
1324         merge_bases = get_merge_bases(upstream, head);
1325         if (!merge_bases || merge_bases->next)
1326                 goto done;
1327
1328         if (!oideq(&onto->object.oid, &merge_bases->item->object.oid))
1329                 goto done;
1330
1331         res = 1;
1332
1333 done:
1334         free_commit_list(merge_bases);
1335         return res && is_linear_history(onto, head);
1336 }
1337
1338 static int parse_opt_am(const struct option *opt, const char *arg, int unset)
1339 {
1340         struct rebase_options *opts = opt->value;
1341
1342         BUG_ON_OPT_NEG(unset);
1343         BUG_ON_OPT_ARG(arg);
1344
1345         opts->type = REBASE_APPLY;
1346
1347         return 0;
1348 }
1349
1350 /* -i followed by -m is still -i */
1351 static int parse_opt_merge(const struct option *opt, const char *arg, int unset)
1352 {
1353         struct rebase_options *opts = opt->value;
1354
1355         BUG_ON_OPT_NEG(unset);
1356         BUG_ON_OPT_ARG(arg);
1357
1358         if (!is_merge(opts))
1359                 opts->type = REBASE_MERGE;
1360
1361         return 0;
1362 }
1363
1364 /* -i followed by -p is still explicitly interactive, but -p alone is not */
1365 static int parse_opt_interactive(const struct option *opt, const char *arg,
1366                                  int unset)
1367 {
1368         struct rebase_options *opts = opt->value;
1369
1370         BUG_ON_OPT_NEG(unset);
1371         BUG_ON_OPT_ARG(arg);
1372
1373         opts->type = REBASE_MERGE;
1374         opts->flags |= REBASE_INTERACTIVE_EXPLICIT;
1375
1376         return 0;
1377 }
1378
1379 static enum empty_type parse_empty_value(const char *value)
1380 {
1381         if (!strcasecmp(value, "drop"))
1382                 return EMPTY_DROP;
1383         else if (!strcasecmp(value, "keep"))
1384                 return EMPTY_KEEP;
1385         else if (!strcasecmp(value, "ask"))
1386                 return EMPTY_ASK;
1387
1388         die(_("unrecognized empty type '%s'; valid values are \"drop\", \"keep\", and \"ask\"."), value);
1389 }
1390
1391 static int parse_opt_empty(const struct option *opt, const char *arg, int unset)
1392 {
1393         struct rebase_options *options = opt->value;
1394         enum empty_type value = parse_empty_value(arg);
1395
1396         BUG_ON_OPT_NEG(unset);
1397
1398         options->empty = value;
1399         return 0;
1400 }
1401
1402 static void NORETURN error_on_missing_default_upstream(void)
1403 {
1404         struct branch *current_branch = branch_get(NULL);
1405
1406         printf(_("%s\n"
1407                  "Please specify which branch you want to rebase against.\n"
1408                  "See git-rebase(1) for details.\n"
1409                  "\n"
1410                  "    git rebase '<branch>'\n"
1411                  "\n"),
1412                 current_branch ? _("There is no tracking information for "
1413                         "the current branch.") :
1414                         _("You are not currently on a branch."));
1415
1416         if (current_branch) {
1417                 const char *remote = current_branch->remote_name;
1418
1419                 if (!remote)
1420                         remote = _("<remote>");
1421
1422                 printf(_("If you wish to set tracking information for this "
1423                          "branch you can do so with:\n"
1424                          "\n"
1425                          "    git branch --set-upstream-to=%s/<branch> %s\n"
1426                          "\n"),
1427                        remote, current_branch->name);
1428         }
1429         exit(1);
1430 }
1431
1432 static void set_reflog_action(struct rebase_options *options)
1433 {
1434         const char *env;
1435         struct strbuf buf = STRBUF_INIT;
1436
1437         if (!is_merge(options))
1438                 return;
1439
1440         env = getenv(GIT_REFLOG_ACTION_ENVIRONMENT);
1441         if (env && strcmp("rebase", env))
1442                 return; /* only override it if it is "rebase" */
1443
1444         strbuf_addf(&buf, "rebase (%s)", options->action);
1445         setenv(GIT_REFLOG_ACTION_ENVIRONMENT, buf.buf, 1);
1446         strbuf_release(&buf);
1447 }
1448
1449 static int check_exec_cmd(const char *cmd)
1450 {
1451         if (strchr(cmd, '\n'))
1452                 return error(_("exec commands cannot contain newlines"));
1453
1454         /* Does the command consist purely of whitespace? */
1455         if (!cmd[strspn(cmd, " \t\r\f\v")])
1456                 return error(_("empty exec command"));
1457
1458         return 0;
1459 }
1460
1461
1462 int cmd_rebase(int argc, const char **argv, const char *prefix)
1463 {
1464         struct rebase_options options = REBASE_OPTIONS_INIT;
1465         const char *branch_name;
1466         int ret, flags, total_argc, in_progress = 0;
1467         int keep_base = 0;
1468         int ok_to_skip_pre_rebase = 0;
1469         struct strbuf msg = STRBUF_INIT;
1470         struct strbuf revisions = STRBUF_INIT;
1471         struct strbuf buf = STRBUF_INIT;
1472         struct object_id merge_base;
1473         int ignore_whitespace = 0;
1474         enum action action = ACTION_NONE;
1475         const char *gpg_sign = NULL;
1476         struct string_list exec = STRING_LIST_INIT_NODUP;
1477         const char *rebase_merges = NULL;
1478         int fork_point = -1;
1479         struct string_list strategy_options = STRING_LIST_INIT_NODUP;
1480         struct object_id squash_onto;
1481         char *squash_onto_name = NULL;
1482         int reschedule_failed_exec = -1;
1483         int allow_preemptive_ff = 1;
1484         struct option builtin_rebase_options[] = {
1485                 OPT_STRING(0, "onto", &options.onto_name,
1486                            N_("revision"),
1487                            N_("rebase onto given branch instead of upstream")),
1488                 OPT_BOOL(0, "keep-base", &keep_base,
1489                          N_("use the merge-base of upstream and branch as the current base")),
1490                 OPT_BOOL(0, "no-verify", &ok_to_skip_pre_rebase,
1491                          N_("allow pre-rebase hook to run")),
1492                 OPT_NEGBIT('q', "quiet", &options.flags,
1493                            N_("be quiet. implies --no-stat"),
1494                            REBASE_NO_QUIET | REBASE_VERBOSE | REBASE_DIFFSTAT),
1495                 OPT_BIT('v', "verbose", &options.flags,
1496                         N_("display a diffstat of what changed upstream"),
1497                         REBASE_NO_QUIET | REBASE_VERBOSE | REBASE_DIFFSTAT),
1498                 {OPTION_NEGBIT, 'n', "no-stat", &options.flags, NULL,
1499                         N_("do not show diffstat of what changed upstream"),
1500                         PARSE_OPT_NOARG, NULL, REBASE_DIFFSTAT },
1501                 OPT_BOOL(0, "signoff", &options.signoff,
1502                          N_("add a Signed-off-by: line to each commit")),
1503                 OPT_BOOL(0, "committer-date-is-author-date",
1504                          &options.committer_date_is_author_date,
1505                          N_("make committer date match author date")),
1506                 OPT_PASSTHRU_ARGV(0, "ignore-date", &options.git_am_opts, NULL,
1507                                   N_("passed to 'git am'"), PARSE_OPT_NOARG),
1508                 OPT_PASSTHRU_ARGV('C', NULL, &options.git_am_opts, N_("n"),
1509                                   N_("passed to 'git apply'"), 0),
1510                 OPT_BOOL(0, "ignore-whitespace", &ignore_whitespace,
1511                          N_("ignore changes in whitespace")),
1512                 OPT_PASSTHRU_ARGV(0, "whitespace", &options.git_am_opts,
1513                                   N_("action"), N_("passed to 'git apply'"), 0),
1514                 OPT_BIT('f', "force-rebase", &options.flags,
1515                         N_("cherry-pick all commits, even if unchanged"),
1516                         REBASE_FORCE),
1517                 OPT_BIT(0, "no-ff", &options.flags,
1518                         N_("cherry-pick all commits, even if unchanged"),
1519                         REBASE_FORCE),
1520                 OPT_CMDMODE(0, "continue", &action, N_("continue"),
1521                             ACTION_CONTINUE),
1522                 OPT_CMDMODE(0, "skip", &action,
1523                             N_("skip current patch and continue"), ACTION_SKIP),
1524                 OPT_CMDMODE(0, "abort", &action,
1525                             N_("abort and check out the original branch"),
1526                             ACTION_ABORT),
1527                 OPT_CMDMODE(0, "quit", &action,
1528                             N_("abort but keep HEAD where it is"), ACTION_QUIT),
1529                 OPT_CMDMODE(0, "edit-todo", &action, N_("edit the todo list "
1530                             "during an interactive rebase"), ACTION_EDIT_TODO),
1531                 OPT_CMDMODE(0, "show-current-patch", &action,
1532                             N_("show the patch file being applied or merged"),
1533                             ACTION_SHOW_CURRENT_PATCH),
1534                 { OPTION_CALLBACK, 0, "apply", &options, NULL,
1535                         N_("use apply strategies to rebase"),
1536                         PARSE_OPT_NOARG | PARSE_OPT_NONEG,
1537                         parse_opt_am },
1538                 { OPTION_CALLBACK, 'm', "merge", &options, NULL,
1539                         N_("use merging strategies to rebase"),
1540                         PARSE_OPT_NOARG | PARSE_OPT_NONEG,
1541                         parse_opt_merge },
1542                 { OPTION_CALLBACK, 'i', "interactive", &options, NULL,
1543                         N_("let the user edit the list of commits to rebase"),
1544                         PARSE_OPT_NOARG | PARSE_OPT_NONEG,
1545                         parse_opt_interactive },
1546                 OPT_SET_INT_F('p', "preserve-merges", &options.type,
1547                               N_("(DEPRECATED) try to recreate merges instead of "
1548                                  "ignoring them"),
1549                               REBASE_PRESERVE_MERGES, PARSE_OPT_HIDDEN),
1550                 OPT_RERERE_AUTOUPDATE(&options.allow_rerere_autoupdate),
1551                 OPT_CALLBACK_F(0, "empty", &options, "{drop,keep,ask}",
1552                                N_("how to handle commits that become empty"),
1553                                PARSE_OPT_NONEG, parse_opt_empty),
1554                 { OPTION_CALLBACK, 'k', "keep-empty", &options, NULL,
1555                         N_("(DEPRECATED) keep empty commits"),
1556                         PARSE_OPT_NOARG | PARSE_OPT_HIDDEN,
1557                         parse_opt_keep_empty },
1558                 OPT_BOOL(0, "autosquash", &options.autosquash,
1559                          N_("move commits that begin with "
1560                             "squash!/fixup! under -i")),
1561                 { OPTION_STRING, 'S', "gpg-sign", &gpg_sign, N_("key-id"),
1562                         N_("GPG-sign commits"),
1563                         PARSE_OPT_OPTARG, NULL, (intptr_t) "" },
1564                 OPT_BOOL(0, "autostash", &options.autostash,
1565                          N_("automatically stash/stash pop before and after")),
1566                 OPT_STRING_LIST('x', "exec", &exec, N_("exec"),
1567                                 N_("add exec lines after each commit of the "
1568                                    "editable list")),
1569                 OPT_BOOL_F(0, "allow-empty-message",
1570                            &options.allow_empty_message,
1571                            N_("allow rebasing commits with empty messages"),
1572                            PARSE_OPT_HIDDEN),
1573                 {OPTION_STRING, 'r', "rebase-merges", &rebase_merges,
1574                         N_("mode"),
1575                         N_("try to rebase merges instead of skipping them"),
1576                         PARSE_OPT_OPTARG, NULL, (intptr_t)""},
1577                 OPT_BOOL(0, "fork-point", &fork_point,
1578                          N_("use 'merge-base --fork-point' to refine upstream")),
1579                 OPT_STRING('s', "strategy", &options.strategy,
1580                            N_("strategy"), N_("use the given merge strategy")),
1581                 OPT_STRING_LIST('X', "strategy-option", &strategy_options,
1582                                 N_("option"),
1583                                 N_("pass the argument through to the merge "
1584                                    "strategy")),
1585                 OPT_BOOL(0, "root", &options.root,
1586                          N_("rebase all reachable commits up to the root(s)")),
1587                 OPT_BOOL(0, "reschedule-failed-exec",
1588                          &reschedule_failed_exec,
1589                          N_("automatically re-schedule any `exec` that fails")),
1590                 OPT_END(),
1591         };
1592         int i;
1593
1594         if (argc == 2 && !strcmp(argv[1], "-h"))
1595                 usage_with_options(builtin_rebase_usage,
1596                                    builtin_rebase_options);
1597
1598         options.allow_empty_message = 1;
1599         git_config(rebase_config, &options);
1600
1601         if (options.use_legacy_rebase ||
1602             !git_env_bool("GIT_TEST_REBASE_USE_BUILTIN", -1))
1603                 warning(_("the rebase.useBuiltin support has been removed!\n"
1604                           "See its entry in 'git help config' for details."));
1605
1606         strbuf_reset(&buf);
1607         strbuf_addf(&buf, "%s/applying", apply_dir());
1608         if(file_exists(buf.buf))
1609                 die(_("It looks like 'git am' is in progress. Cannot rebase."));
1610
1611         if (is_directory(apply_dir())) {
1612                 options.type = REBASE_APPLY;
1613                 options.state_dir = apply_dir();
1614         } else if (is_directory(merge_dir())) {
1615                 strbuf_reset(&buf);
1616                 strbuf_addf(&buf, "%s/rewritten", merge_dir());
1617                 if (is_directory(buf.buf)) {
1618                         options.type = REBASE_PRESERVE_MERGES;
1619                         options.flags |= REBASE_INTERACTIVE_EXPLICIT;
1620                 } else {
1621                         strbuf_reset(&buf);
1622                         strbuf_addf(&buf, "%s/interactive", merge_dir());
1623                         if(file_exists(buf.buf)) {
1624                                 options.type = REBASE_MERGE;
1625                                 options.flags |= REBASE_INTERACTIVE_EXPLICIT;
1626                         } else
1627                                 options.type = REBASE_MERGE;
1628                 }
1629                 options.state_dir = merge_dir();
1630         }
1631
1632         if (options.type != REBASE_UNSPECIFIED)
1633                 in_progress = 1;
1634
1635         total_argc = argc;
1636         argc = parse_options(argc, argv, prefix,
1637                              builtin_rebase_options,
1638                              builtin_rebase_usage, 0);
1639
1640         if (action != ACTION_NONE && total_argc != 2) {
1641                 usage_with_options(builtin_rebase_usage,
1642                                    builtin_rebase_options);
1643         }
1644
1645         if (argc > 2)
1646                 usage_with_options(builtin_rebase_usage,
1647                                    builtin_rebase_options);
1648
1649         if (options.type == REBASE_PRESERVE_MERGES)
1650                 warning(_("git rebase --preserve-merges is deprecated. "
1651                           "Use --rebase-merges instead."));
1652
1653         if (keep_base) {
1654                 if (options.onto_name)
1655                         die(_("cannot combine '--keep-base' with '--onto'"));
1656                 if (options.root)
1657                         die(_("cannot combine '--keep-base' with '--root'"));
1658         }
1659
1660         if (action != ACTION_NONE && !in_progress)
1661                 die(_("No rebase in progress?"));
1662         setenv(GIT_REFLOG_ACTION_ENVIRONMENT, "rebase", 0);
1663
1664         if (action == ACTION_EDIT_TODO && !is_merge(&options))
1665                 die(_("The --edit-todo action can only be used during "
1666                       "interactive rebase."));
1667
1668         if (trace2_is_enabled()) {
1669                 if (is_merge(&options))
1670                         trace2_cmd_mode("interactive");
1671                 else if (exec.nr)
1672                         trace2_cmd_mode("interactive-exec");
1673                 else
1674                         trace2_cmd_mode(action_names[action]);
1675         }
1676
1677         switch (action) {
1678         case ACTION_CONTINUE: {
1679                 struct object_id head;
1680                 struct lock_file lock_file = LOCK_INIT;
1681                 int fd;
1682
1683                 options.action = "continue";
1684                 set_reflog_action(&options);
1685
1686                 /* Sanity check */
1687                 if (get_oid("HEAD", &head))
1688                         die(_("Cannot read HEAD"));
1689
1690                 fd = hold_locked_index(&lock_file, 0);
1691                 if (repo_read_index(the_repository) < 0)
1692                         die(_("could not read index"));
1693                 refresh_index(the_repository->index, REFRESH_QUIET, NULL, NULL,
1694                               NULL);
1695                 if (0 <= fd)
1696                         repo_update_index_if_able(the_repository, &lock_file);
1697                 rollback_lock_file(&lock_file);
1698
1699                 if (has_unstaged_changes(the_repository, 1)) {
1700                         puts(_("You must edit all merge conflicts and then\n"
1701                                "mark them as resolved using git add"));
1702                         exit(1);
1703                 }
1704                 if (read_basic_state(&options))
1705                         exit(1);
1706                 goto run_rebase;
1707         }
1708         case ACTION_SKIP: {
1709                 struct string_list merge_rr = STRING_LIST_INIT_DUP;
1710
1711                 options.action = "skip";
1712                 set_reflog_action(&options);
1713
1714                 rerere_clear(the_repository, &merge_rr);
1715                 string_list_clear(&merge_rr, 1);
1716
1717                 if (reset_head(NULL, "reset", NULL, RESET_HEAD_HARD,
1718                                NULL, NULL) < 0)
1719                         die(_("could not discard worktree changes"));
1720                 remove_branch_state(the_repository, 0);
1721                 if (read_basic_state(&options))
1722                         exit(1);
1723                 goto run_rebase;
1724         }
1725         case ACTION_ABORT: {
1726                 struct string_list merge_rr = STRING_LIST_INIT_DUP;
1727                 options.action = "abort";
1728                 set_reflog_action(&options);
1729
1730                 rerere_clear(the_repository, &merge_rr);
1731                 string_list_clear(&merge_rr, 1);
1732
1733                 if (read_basic_state(&options))
1734                         exit(1);
1735                 if (reset_head(&options.orig_head, "reset",
1736                                options.head_name, RESET_HEAD_HARD,
1737                                NULL, NULL) < 0)
1738                         die(_("could not move back to %s"),
1739                             oid_to_hex(&options.orig_head));
1740                 remove_branch_state(the_repository, 0);
1741                 ret = !!finish_rebase(&options);
1742                 goto cleanup;
1743         }
1744         case ACTION_QUIT: {
1745                 if (options.type == REBASE_MERGE) {
1746                         struct replay_opts replay = REPLAY_OPTS_INIT;
1747
1748                         replay.action = REPLAY_INTERACTIVE_REBASE;
1749                         ret = !!sequencer_remove_state(&replay);
1750                 } else {
1751                         strbuf_reset(&buf);
1752                         strbuf_addstr(&buf, options.state_dir);
1753                         ret = !!remove_dir_recursively(&buf, 0);
1754                         if (ret)
1755                                 error(_("could not remove '%s'"),
1756                                        options.state_dir);
1757                 }
1758                 goto cleanup;
1759         }
1760         case ACTION_EDIT_TODO:
1761                 options.action = "edit-todo";
1762                 options.dont_finish_rebase = 1;
1763                 goto run_rebase;
1764         case ACTION_SHOW_CURRENT_PATCH:
1765                 options.action = "show-current-patch";
1766                 options.dont_finish_rebase = 1;
1767                 goto run_rebase;
1768         case ACTION_NONE:
1769                 break;
1770         default:
1771                 BUG("action: %d", action);
1772         }
1773
1774         /* Make sure no rebase is in progress */
1775         if (in_progress) {
1776                 const char *last_slash = strrchr(options.state_dir, '/');
1777                 const char *state_dir_base =
1778                         last_slash ? last_slash + 1 : options.state_dir;
1779                 const char *cmd_live_rebase =
1780                         "git rebase (--continue | --abort | --skip)";
1781                 strbuf_reset(&buf);
1782                 strbuf_addf(&buf, "rm -fr \"%s\"", options.state_dir);
1783                 die(_("It seems that there is already a %s directory, and\n"
1784                       "I wonder if you are in the middle of another rebase.  "
1785                       "If that is the\n"
1786                       "case, please try\n\t%s\n"
1787                       "If that is not the case, please\n\t%s\n"
1788                       "and run me again.  I am stopping in case you still "
1789                       "have something\n"
1790                       "valuable there.\n"),
1791                     state_dir_base, cmd_live_rebase, buf.buf);
1792         }
1793
1794         if ((options.flags & REBASE_INTERACTIVE_EXPLICIT) ||
1795             (action != ACTION_NONE) ||
1796             (exec.nr > 0) ||
1797             options.autosquash) {
1798                 allow_preemptive_ff = 0;
1799         }
1800         if (options.committer_date_is_author_date)
1801                 options.flags |= REBASE_FORCE;
1802
1803         for (i = 0; i < options.git_am_opts.argc; i++) {
1804                 const char *option = options.git_am_opts.argv[i], *p;
1805                 if (!strcmp(option, "--ignore-date") ||
1806                     !strcmp(option, "--whitespace=fix") ||
1807                     !strcmp(option, "--whitespace=strip"))
1808                         allow_preemptive_ff = 0;
1809                 else if (skip_prefix(option, "-C", &p)) {
1810                         while (*p)
1811                                 if (!isdigit(*(p++)))
1812                                         die(_("switch `C' expects a "
1813                                               "numerical value"));
1814                 } else if (skip_prefix(option, "--whitespace=", &p)) {
1815                         if (*p && strcmp(p, "warn") && strcmp(p, "nowarn") &&
1816                             strcmp(p, "error") && strcmp(p, "error-all"))
1817                                 die("Invalid whitespace option: '%s'", p);
1818                 }
1819         }
1820
1821         for (i = 0; i < exec.nr; i++)
1822                 if (check_exec_cmd(exec.items[i].string))
1823                         exit(1);
1824
1825         if (!(options.flags & REBASE_NO_QUIET))
1826                 argv_array_push(&options.git_am_opts, "-q");
1827
1828         if (options.empty != EMPTY_UNSPECIFIED)
1829                 imply_merge(&options, "--empty");
1830
1831         if (gpg_sign) {
1832                 free(options.gpg_sign_opt);
1833                 options.gpg_sign_opt = xstrfmt("-S%s", gpg_sign);
1834         }
1835
1836         if (exec.nr) {
1837                 int i;
1838
1839                 imply_merge(&options, "--exec");
1840
1841                 strbuf_reset(&buf);
1842                 for (i = 0; i < exec.nr; i++)
1843                         strbuf_addf(&buf, "exec %s\n", exec.items[i].string);
1844                 options.cmd = xstrdup(buf.buf);
1845         }
1846
1847         if (rebase_merges) {
1848                 if (!*rebase_merges)
1849                         ; /* default mode; do nothing */
1850                 else if (!strcmp("rebase-cousins", rebase_merges))
1851                         options.rebase_cousins = 1;
1852                 else if (strcmp("no-rebase-cousins", rebase_merges))
1853                         die(_("Unknown mode: %s"), rebase_merges);
1854                 options.rebase_merges = 1;
1855                 imply_merge(&options, "--rebase-merges");
1856         }
1857
1858         if (options.type == REBASE_APPLY) {
1859                 if (ignore_whitespace)
1860                         argv_array_push(&options.git_am_opts,
1861                                         "--ignore-whitespace");
1862                 if (options.committer_date_is_author_date)
1863                         argv_array_push(&options.git_am_opts,
1864                                         "--committer-date-is-author-date");
1865         } else {
1866                 /* REBASE_MERGE and PRESERVE_MERGES */
1867                 if (ignore_whitespace) {
1868                         string_list_append(&strategy_options,
1869                                            "ignore-space-change");
1870                 }
1871         }
1872
1873         if (strategy_options.nr) {
1874                 int i;
1875
1876                 if (!options.strategy)
1877                         options.strategy = "recursive";
1878
1879                 strbuf_reset(&buf);
1880                 for (i = 0; i < strategy_options.nr; i++)
1881                         strbuf_addf(&buf, " --%s",
1882                                     strategy_options.items[i].string);
1883                 options.strategy_opts = xstrdup(buf.buf);
1884         }
1885
1886         if (options.strategy) {
1887                 options.strategy = xstrdup(options.strategy);
1888                 switch (options.type) {
1889                 case REBASE_APPLY:
1890                         die(_("--strategy requires --merge or --interactive"));
1891                 case REBASE_MERGE:
1892                 case REBASE_PRESERVE_MERGES:
1893                         /* compatible */
1894                         break;
1895                 case REBASE_UNSPECIFIED:
1896                         options.type = REBASE_MERGE;
1897                         break;
1898                 default:
1899                         BUG("unhandled rebase type (%d)", options.type);
1900                 }
1901         }
1902
1903         if (options.type == REBASE_MERGE)
1904                 imply_merge(&options, "--merge");
1905
1906         if (options.root && !options.onto_name)
1907                 imply_merge(&options, "--root without --onto");
1908
1909         if (isatty(2) && options.flags & REBASE_NO_QUIET)
1910                 strbuf_addstr(&options.git_format_patch_opt, " --progress");
1911
1912         if (options.git_am_opts.argc || options.type == REBASE_APPLY) {
1913                 /* all am options except -q are compatible only with --apply */
1914                 for (i = options.git_am_opts.argc - 1; i >= 0; i--)
1915                         if (strcmp(options.git_am_opts.argv[i], "-q"))
1916                                 break;
1917
1918                 if (i >= 0) {
1919                         if (is_merge(&options))
1920                                 die(_("cannot combine apply options with "
1921                                       "merge options"));
1922                         else
1923                                 options.type = REBASE_APPLY;
1924                 }
1925         }
1926
1927         if (options.type == REBASE_UNSPECIFIED) {
1928                 if (!strcmp(options.default_backend, "merge"))
1929                         imply_merge(&options, "--merge");
1930                 else if (!strcmp(options.default_backend, "apply"))
1931                         options.type = REBASE_APPLY;
1932                 else
1933                         die(_("Unknown rebase backend: %s"),
1934                             options.default_backend);
1935         }
1936
1937         switch (options.type) {
1938         case REBASE_MERGE:
1939         case REBASE_PRESERVE_MERGES:
1940                 options.state_dir = merge_dir();
1941                 break;
1942         case REBASE_APPLY:
1943                 options.state_dir = apply_dir();
1944                 break;
1945         default:
1946                 BUG("options.type was just set above; should be unreachable.");
1947         }
1948
1949         if (options.empty == EMPTY_UNSPECIFIED) {
1950                 if (options.flags & REBASE_INTERACTIVE_EXPLICIT)
1951                         options.empty = EMPTY_ASK;
1952                 else if (exec.nr > 0)
1953                         options.empty = EMPTY_KEEP;
1954                 else
1955                         options.empty = EMPTY_DROP;
1956         }
1957         if (reschedule_failed_exec > 0 && !is_merge(&options))
1958                 die(_("--reschedule-failed-exec requires "
1959                       "--exec or --interactive"));
1960         if (reschedule_failed_exec >= 0)
1961                 options.reschedule_failed_exec = reschedule_failed_exec;
1962
1963         if (options.signoff) {
1964                 if (options.type == REBASE_PRESERVE_MERGES)
1965                         die("cannot combine '--signoff' with "
1966                             "'--preserve-merges'");
1967                 argv_array_push(&options.git_am_opts, "--signoff");
1968                 options.flags |= REBASE_FORCE;
1969         }
1970
1971         if (options.type == REBASE_PRESERVE_MERGES) {
1972                 /*
1973                  * Note: incompatibility with --signoff handled in signoff block above
1974                  * Note: incompatibility with --interactive is just a strong warning;
1975                  *       git-rebase.txt caveats with "unless you know what you are doing"
1976                  */
1977                 if (options.rebase_merges)
1978                         die(_("cannot combine '--preserve-merges' with "
1979                               "'--rebase-merges'"));
1980
1981                 if (options.reschedule_failed_exec)
1982                         die(_("error: cannot combine '--preserve-merges' with "
1983                               "'--reschedule-failed-exec'"));
1984         }
1985
1986         if (!options.root) {
1987                 if (argc < 1) {
1988                         struct branch *branch;
1989
1990                         branch = branch_get(NULL);
1991                         options.upstream_name = branch_get_upstream(branch,
1992                                                                     NULL);
1993                         if (!options.upstream_name)
1994                                 error_on_missing_default_upstream();
1995                         if (fork_point < 0)
1996                                 fork_point = 1;
1997                 } else {
1998                         options.upstream_name = argv[0];
1999                         argc--;
2000                         argv++;
2001                         if (!strcmp(options.upstream_name, "-"))
2002                                 options.upstream_name = "@{-1}";
2003                 }
2004                 options.upstream = peel_committish(options.upstream_name);
2005                 if (!options.upstream)
2006                         die(_("invalid upstream '%s'"), options.upstream_name);
2007                 options.upstream_arg = options.upstream_name;
2008         } else {
2009                 if (!options.onto_name) {
2010                         if (commit_tree("", 0, the_hash_algo->empty_tree, NULL,
2011                                         &squash_onto, NULL, NULL) < 0)
2012                                 die(_("Could not create new root commit"));
2013                         options.squash_onto = &squash_onto;
2014                         options.onto_name = squash_onto_name =
2015                                 xstrdup(oid_to_hex(&squash_onto));
2016                 } else
2017                         options.root_with_onto = 1;
2018
2019                 options.upstream_name = NULL;
2020                 options.upstream = NULL;
2021                 if (argc > 1)
2022                         usage_with_options(builtin_rebase_usage,
2023                                            builtin_rebase_options);
2024                 options.upstream_arg = "--root";
2025         }
2026
2027         /* Make sure the branch to rebase onto is valid. */
2028         if (keep_base) {
2029                 strbuf_reset(&buf);
2030                 strbuf_addstr(&buf, options.upstream_name);
2031                 strbuf_addstr(&buf, "...");
2032                 options.onto_name = xstrdup(buf.buf);
2033         } else if (!options.onto_name)
2034                 options.onto_name = options.upstream_name;
2035         if (strstr(options.onto_name, "...")) {
2036                 if (get_oid_mb(options.onto_name, &merge_base) < 0) {
2037                         if (keep_base)
2038                                 die(_("'%s': need exactly one merge base with branch"),
2039                                     options.upstream_name);
2040                         else
2041                                 die(_("'%s': need exactly one merge base"),
2042                                     options.onto_name);
2043                 }
2044                 options.onto = lookup_commit_or_die(&merge_base,
2045                                                     options.onto_name);
2046         } else {
2047                 options.onto = peel_committish(options.onto_name);
2048                 if (!options.onto)
2049                         die(_("Does not point to a valid commit '%s'"),
2050                                 options.onto_name);
2051         }
2052
2053         /*
2054          * If the branch to rebase is given, that is the branch we will rebase
2055          * branch_name -- branch/commit being rebased, or
2056          *                HEAD (already detached)
2057          * orig_head -- commit object name of tip of the branch before rebasing
2058          * head_name -- refs/heads/<that-branch> or NULL (detached HEAD)
2059          */
2060         if (argc == 1) {
2061                 /* Is it "rebase other branchname" or "rebase other commit"? */
2062                 branch_name = argv[0];
2063                 options.switch_to = argv[0];
2064
2065                 /* Is it a local branch? */
2066                 strbuf_reset(&buf);
2067                 strbuf_addf(&buf, "refs/heads/%s", branch_name);
2068                 if (!read_ref(buf.buf, &options.orig_head)) {
2069                         die_if_checked_out(buf.buf, 1);
2070                         options.head_name = xstrdup(buf.buf);
2071                 /* If not is it a valid ref (branch or commit)? */
2072                 } else if (!get_oid(branch_name, &options.orig_head))
2073                         options.head_name = NULL;
2074                 else
2075                         die(_("fatal: no such branch/commit '%s'"),
2076                             branch_name);
2077         } else if (argc == 0) {
2078                 /* Do not need to switch branches, we are already on it. */
2079                 options.head_name =
2080                         xstrdup_or_null(resolve_ref_unsafe("HEAD", 0, NULL,
2081                                          &flags));
2082                 if (!options.head_name)
2083                         die(_("No such ref: %s"), "HEAD");
2084                 if (flags & REF_ISSYMREF) {
2085                         if (!skip_prefix(options.head_name,
2086                                          "refs/heads/", &branch_name))
2087                                 branch_name = options.head_name;
2088
2089                 } else {
2090                         FREE_AND_NULL(options.head_name);
2091                         branch_name = "HEAD";
2092                 }
2093                 if (get_oid("HEAD", &options.orig_head))
2094                         die(_("Could not resolve HEAD to a revision"));
2095         } else
2096                 BUG("unexpected number of arguments left to parse");
2097
2098         if (fork_point > 0) {
2099                 struct commit *head =
2100                         lookup_commit_reference(the_repository,
2101                                                 &options.orig_head);
2102                 options.restrict_revision =
2103                         get_fork_point(options.upstream_name, head);
2104         }
2105
2106         if (repo_read_index(the_repository) < 0)
2107                 die(_("could not read index"));
2108
2109         if (options.autostash) {
2110                 struct lock_file lock_file = LOCK_INIT;
2111                 int fd;
2112
2113                 fd = hold_locked_index(&lock_file, 0);
2114                 refresh_cache(REFRESH_QUIET);
2115                 if (0 <= fd)
2116                         repo_update_index_if_able(the_repository, &lock_file);
2117                 rollback_lock_file(&lock_file);
2118
2119                 if (has_unstaged_changes(the_repository, 1) ||
2120                     has_uncommitted_changes(the_repository, 1)) {
2121                         const char *autostash =
2122                                 state_dir_path("autostash", &options);
2123                         struct child_process stash = CHILD_PROCESS_INIT;
2124                         struct object_id oid;
2125
2126                         argv_array_pushl(&stash.args,
2127                                          "stash", "create", "autostash", NULL);
2128                         stash.git_cmd = 1;
2129                         stash.no_stdin = 1;
2130                         strbuf_reset(&buf);
2131                         if (capture_command(&stash, &buf, GIT_MAX_HEXSZ))
2132                                 die(_("Cannot autostash"));
2133                         strbuf_trim_trailing_newline(&buf);
2134                         if (get_oid(buf.buf, &oid))
2135                                 die(_("Unexpected stash response: '%s'"),
2136                                     buf.buf);
2137                         strbuf_reset(&buf);
2138                         strbuf_add_unique_abbrev(&buf, &oid, DEFAULT_ABBREV);
2139
2140                         if (safe_create_leading_directories_const(autostash))
2141                                 die(_("Could not create directory for '%s'"),
2142                                     options.state_dir);
2143                         write_file(autostash, "%s", oid_to_hex(&oid));
2144                         printf(_("Created autostash: %s\n"), buf.buf);
2145                         if (reset_head(NULL, "reset --hard",
2146                                        NULL, RESET_HEAD_HARD, NULL, NULL) < 0)
2147                                 die(_("could not reset --hard"));
2148
2149                         if (discard_index(the_repository->index) < 0 ||
2150                                 repo_read_index(the_repository) < 0)
2151                                 die(_("could not read index"));
2152                 }
2153         }
2154
2155         if (require_clean_work_tree(the_repository, "rebase",
2156                                     _("Please commit or stash them."), 1, 1)) {
2157                 ret = 1;
2158                 goto cleanup;
2159         }
2160
2161         /*
2162          * Now we are rebasing commits upstream..orig_head (or with --root,
2163          * everything leading up to orig_head) on top of onto.
2164          */
2165
2166         /*
2167          * Check if we are already based on onto with linear history,
2168          * in which case we could fast-forward without replacing the commits
2169          * with new commits recreated by replaying their changes.
2170          *
2171          * Note that can_fast_forward() initializes merge_base, so we have to
2172          * call it before checking allow_preemptive_ff.
2173          */
2174         if (can_fast_forward(options.onto, options.upstream, options.restrict_revision,
2175                     &options.orig_head, &merge_base) &&
2176             allow_preemptive_ff) {
2177                 int flag;
2178
2179                 if (!(options.flags & REBASE_FORCE)) {
2180                         /* Lazily switch to the target branch if needed... */
2181                         if (options.switch_to) {
2182                                 strbuf_reset(&buf);
2183                                 strbuf_addf(&buf, "%s: checkout %s",
2184                                             getenv(GIT_REFLOG_ACTION_ENVIRONMENT),
2185                                             options.switch_to);
2186                                 if (reset_head(&options.orig_head, "checkout",
2187                                                options.head_name,
2188                                                RESET_HEAD_RUN_POST_CHECKOUT_HOOK,
2189                                                NULL, buf.buf) < 0) {
2190                                         ret = !!error(_("could not switch to "
2191                                                         "%s"),
2192                                                       options.switch_to);
2193                                         goto cleanup;
2194                                 }
2195                         }
2196
2197                         if (!(options.flags & REBASE_NO_QUIET))
2198                                 ; /* be quiet */
2199                         else if (!strcmp(branch_name, "HEAD") &&
2200                                  resolve_ref_unsafe("HEAD", 0, NULL, &flag))
2201                                 puts(_("HEAD is up to date."));
2202                         else
2203                                 printf(_("Current branch %s is up to date.\n"),
2204                                        branch_name);
2205                         ret = !!finish_rebase(&options);
2206                         goto cleanup;
2207                 } else if (!(options.flags & REBASE_NO_QUIET))
2208                         ; /* be quiet */
2209                 else if (!strcmp(branch_name, "HEAD") &&
2210                          resolve_ref_unsafe("HEAD", 0, NULL, &flag))
2211                         puts(_("HEAD is up to date, rebase forced."));
2212                 else
2213                         printf(_("Current branch %s is up to date, rebase "
2214                                  "forced.\n"), branch_name);
2215         }
2216
2217         /* If a hook exists, give it a chance to interrupt*/
2218         if (!ok_to_skip_pre_rebase &&
2219             run_hook_le(NULL, "pre-rebase", options.upstream_arg,
2220                         argc ? argv[0] : NULL, NULL))
2221                 die(_("The pre-rebase hook refused to rebase."));
2222
2223         if (options.flags & REBASE_DIFFSTAT) {
2224                 struct diff_options opts;
2225
2226                 if (options.flags & REBASE_VERBOSE) {
2227                         if (is_null_oid(&merge_base))
2228                                 printf(_("Changes to %s:\n"),
2229                                        oid_to_hex(&options.onto->object.oid));
2230                         else
2231                                 printf(_("Changes from %s to %s:\n"),
2232                                        oid_to_hex(&merge_base),
2233                                        oid_to_hex(&options.onto->object.oid));
2234                 }
2235
2236                 /* We want color (if set), but no pager */
2237                 diff_setup(&opts);
2238                 opts.stat_width = -1; /* use full terminal width */
2239                 opts.stat_graph_width = -1; /* respect statGraphWidth config */
2240                 opts.output_format |=
2241                         DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
2242                 opts.detect_rename = DIFF_DETECT_RENAME;
2243                 diff_setup_done(&opts);
2244                 diff_tree_oid(is_null_oid(&merge_base) ?
2245                               the_hash_algo->empty_tree : &merge_base,
2246                               &options.onto->object.oid, "", &opts);
2247                 diffcore_std(&opts);
2248                 diff_flush(&opts);
2249         }
2250
2251         if (is_merge(&options))
2252                 goto run_rebase;
2253
2254         /* Detach HEAD and reset the tree */
2255         if (options.flags & REBASE_NO_QUIET)
2256                 printf(_("First, rewinding head to replay your work on top of "
2257                          "it...\n"));
2258
2259         strbuf_addf(&msg, "%s: checkout %s",
2260                     getenv(GIT_REFLOG_ACTION_ENVIRONMENT), options.onto_name);
2261         if (reset_head(&options.onto->object.oid, "checkout", NULL,
2262                        RESET_HEAD_DETACH | RESET_ORIG_HEAD |
2263                        RESET_HEAD_RUN_POST_CHECKOUT_HOOK,
2264                        NULL, msg.buf))
2265                 die(_("Could not detach HEAD"));
2266         strbuf_release(&msg);
2267
2268         /*
2269          * If the onto is a proper descendant of the tip of the branch, then
2270          * we just fast-forwarded.
2271          */
2272         strbuf_reset(&msg);
2273         if (oideq(&merge_base, &options.orig_head)) {
2274                 printf(_("Fast-forwarded %s to %s.\n"),
2275                         branch_name, options.onto_name);
2276                 strbuf_addf(&msg, "rebase finished: %s onto %s",
2277                         options.head_name ? options.head_name : "detached HEAD",
2278                         oid_to_hex(&options.onto->object.oid));
2279                 reset_head(NULL, "Fast-forwarded", options.head_name,
2280                            RESET_HEAD_REFS_ONLY, "HEAD", msg.buf);
2281                 strbuf_release(&msg);
2282                 ret = !!finish_rebase(&options);
2283                 goto cleanup;
2284         }
2285
2286         strbuf_addf(&revisions, "%s..%s",
2287                     options.root ? oid_to_hex(&options.onto->object.oid) :
2288                     (options.restrict_revision ?
2289                      oid_to_hex(&options.restrict_revision->object.oid) :
2290                      oid_to_hex(&options.upstream->object.oid)),
2291                     oid_to_hex(&options.orig_head));
2292
2293         options.revisions = revisions.buf;
2294
2295 run_rebase:
2296         ret = !!run_specific_rebase(&options, action);
2297
2298 cleanup:
2299         strbuf_release(&buf);
2300         strbuf_release(&revisions);
2301         free(options.head_name);
2302         free(options.gpg_sign_opt);
2303         free(options.cmd);
2304         free(squash_onto_name);
2305         return ret;
2306 }