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