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

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