builtin / rebase.con commit sequencer: rename reset_for_rollback to reset_merge (918d1e6)
   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
  31static char const * const builtin_rebase_usage[] = {
  32        N_("git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] "
  33                "[<upstream>] [<branch>]"),
  34        N_("git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] "
  35                "--root [<branch>]"),
  36        N_("git rebase --continue | --abort | --skip | --edit-todo"),
  37        NULL
  38};
  39
  40static GIT_PATH_FUNC(path_squash_onto, "rebase-merge/squash-onto")
  41static GIT_PATH_FUNC(path_interactive, "rebase-merge/interactive")
  42static GIT_PATH_FUNC(apply_dir, "rebase-apply")
  43static GIT_PATH_FUNC(merge_dir, "rebase-merge")
  44
  45enum rebase_type {
  46        REBASE_UNSPECIFIED = -1,
  47        REBASE_AM,
  48        REBASE_MERGE,
  49        REBASE_INTERACTIVE,
  50        REBASE_PRESERVE_MERGES
  51};
  52
  53struct rebase_options {
  54        enum rebase_type type;
  55        const char *state_dir;
  56        struct commit *upstream;
  57        const char *upstream_name;
  58        const char *upstream_arg;
  59        char *head_name;
  60        struct object_id orig_head;
  61        struct commit *onto;
  62        const char *onto_name;
  63        const char *revisions;
  64        const char *switch_to;
  65        int root;
  66        struct object_id *squash_onto;
  67        struct commit *restrict_revision;
  68        int dont_finish_rebase;
  69        enum {
  70                REBASE_NO_QUIET = 1<<0,
  71                REBASE_VERBOSE = 1<<1,
  72                REBASE_DIFFSTAT = 1<<2,
  73                REBASE_FORCE = 1<<3,
  74                REBASE_INTERACTIVE_EXPLICIT = 1<<4,
  75        } flags;
  76        struct argv_array git_am_opts;
  77        const char *action;
  78        int signoff;
  79        int allow_rerere_autoupdate;
  80        int keep_empty;
  81        int autosquash;
  82        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
 100static 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        return replay;
 121}
 122
 123enum action {
 124        ACTION_NONE = 0,
 125        ACTION_CONTINUE,
 126        ACTION_SKIP,
 127        ACTION_ABORT,
 128        ACTION_QUIT,
 129        ACTION_EDIT_TODO,
 130        ACTION_SHOW_CURRENT_PATCH,
 131        ACTION_SHORTEN_OIDS,
 132        ACTION_EXPAND_OIDS,
 133        ACTION_CHECK_TODO_LIST,
 134        ACTION_REARRANGE_SQUASH,
 135        ACTION_ADD_EXEC
 136};
 137
 138static const char *action_names[] = { "undefined",
 139                                      "continue",
 140                                      "skip",
 141                                      "abort",
 142                                      "quit",
 143                                      "edit_todo",
 144                                      "show_current_patch" };
 145
 146static int add_exec_commands(struct string_list *commands)
 147{
 148        const char *todo_file = rebase_path_todo();
 149        struct todo_list todo_list = TODO_LIST_INIT;
 150        int res;
 151
 152        if (strbuf_read_file(&todo_list.buf, todo_file, 0) < 0)
 153                return error_errno(_("could not read '%s'."), todo_file);
 154
 155        if (todo_list_parse_insn_buffer(the_repository, todo_list.buf.buf,
 156                                        &todo_list)) {
 157                todo_list_release(&todo_list);
 158                return error(_("unusable todo list: '%s'"), todo_file);
 159        }
 160
 161        todo_list_add_exec_commands(&todo_list, commands);
 162        res = todo_list_write_to_file(the_repository, &todo_list,
 163                                      todo_file, NULL, NULL, -1, 0);
 164        todo_list_release(&todo_list);
 165
 166        if (res)
 167                return error_errno(_("could not write '%s'."), todo_file);
 168        return 0;
 169}
 170
 171static int rearrange_squash_in_todo_file(void)
 172{
 173        const char *todo_file = rebase_path_todo();
 174        struct todo_list todo_list = TODO_LIST_INIT;
 175        int res = 0;
 176
 177        if (strbuf_read_file(&todo_list.buf, todo_file, 0) < 0)
 178                return error_errno(_("could not read '%s'."), todo_file);
 179        if (todo_list_parse_insn_buffer(the_repository, todo_list.buf.buf,
 180                                        &todo_list)) {
 181                todo_list_release(&todo_list);
 182                return error(_("unusable todo list: '%s'"), todo_file);
 183        }
 184
 185        res = todo_list_rearrange_squash(&todo_list);
 186        if (!res)
 187                res = todo_list_write_to_file(the_repository, &todo_list,
 188                                              todo_file, NULL, NULL, -1, 0);
 189
 190        todo_list_release(&todo_list);
 191
 192        if (res)
 193                return error_errno(_("could not write '%s'."), todo_file);
 194        return 0;
 195}
 196
 197static int transform_todo_file(unsigned flags)
 198{
 199        const char *todo_file = rebase_path_todo();
 200        struct todo_list todo_list = TODO_LIST_INIT;
 201        int res;
 202
 203        if (strbuf_read_file(&todo_list.buf, todo_file, 0) < 0)
 204                return error_errno(_("could not read '%s'."), todo_file);
 205
 206        if (todo_list_parse_insn_buffer(the_repository, todo_list.buf.buf,
 207                                        &todo_list)) {
 208                todo_list_release(&todo_list);
 209                return error(_("unusable todo list: '%s'"), todo_file);
 210        }
 211
 212        res = todo_list_write_to_file(the_repository, &todo_list, todo_file,
 213                                      NULL, NULL, -1, flags);
 214        todo_list_release(&todo_list);
 215
 216        if (res)
 217                return error_errno(_("could not write '%s'."), todo_file);
 218        return 0;
 219}
 220
 221static int edit_todo_file(unsigned flags)
 222{
 223        const char *todo_file = rebase_path_todo();
 224        struct todo_list todo_list = TODO_LIST_INIT,
 225                new_todo = TODO_LIST_INIT;
 226        int res = 0;
 227
 228        if (strbuf_read_file(&todo_list.buf, todo_file, 0) < 0)
 229                return error_errno(_("could not read '%s'."), todo_file);
 230
 231        strbuf_stripspace(&todo_list.buf, 1);
 232        res = edit_todo_list(the_repository, &todo_list, &new_todo, NULL, NULL, flags);
 233        if (!res && todo_list_write_to_file(the_repository, &new_todo, todo_file,
 234                                            NULL, NULL, -1, flags & ~(TODO_LIST_SHORTEN_IDS)))
 235                res = error_errno(_("could not write '%s'"), todo_file);
 236
 237        todo_list_release(&todo_list);
 238        todo_list_release(&new_todo);
 239
 240        return res;
 241}
 242
 243static int get_revision_ranges(struct commit *upstream, struct commit *onto,
 244                               const char **head_hash,
 245                               char **revisions, char **shortrevisions)
 246{
 247        struct commit *base_rev = upstream ? upstream : onto;
 248        const char *shorthead;
 249        struct object_id orig_head;
 250
 251        if (get_oid("HEAD", &orig_head))
 252                return error(_("no HEAD?"));
 253
 254        *head_hash = find_unique_abbrev(&orig_head, GIT_MAX_HEXSZ);
 255        *revisions = xstrfmt("%s...%s", oid_to_hex(&base_rev->object.oid),
 256                                                   *head_hash);
 257
 258        shorthead = find_unique_abbrev(&orig_head, DEFAULT_ABBREV);
 259
 260        if (upstream) {
 261                const char *shortrev;
 262
 263                shortrev = find_unique_abbrev(&base_rev->object.oid,
 264                                              DEFAULT_ABBREV);
 265
 266                *shortrevisions = xstrfmt("%s..%s", shortrev, shorthead);
 267        } else
 268                *shortrevisions = xstrdup(shorthead);
 269
 270        return 0;
 271}
 272
 273static int init_basic_state(struct replay_opts *opts, const char *head_name,
 274                            struct commit *onto, const char *orig_head)
 275{
 276        FILE *interactive;
 277
 278        if (!is_directory(merge_dir()) && mkdir_in_gitdir(merge_dir()))
 279                return error_errno(_("could not create temporary %s"), merge_dir());
 280
 281        delete_reflog("REBASE_HEAD");
 282
 283        interactive = fopen(path_interactive(), "w");
 284        if (!interactive)
 285                return error_errno(_("could not mark as interactive"));
 286        fclose(interactive);
 287
 288        return write_basic_state(opts, head_name, onto, orig_head);
 289}
 290
 291static void split_exec_commands(const char *cmd, struct string_list *commands)
 292{
 293        if (cmd && *cmd) {
 294                string_list_split(commands, cmd, '\n', -1);
 295
 296                /* rebase.c adds a new line to cmd after every command,
 297                 * so here the last command is always empty */
 298                string_list_remove_empty_items(commands, 0);
 299        }
 300}
 301
 302static int do_interactive_rebase(struct rebase_options *opts, unsigned flags)
 303{
 304        int ret;
 305        const char *head_hash = NULL;
 306        char *revisions = NULL, *shortrevisions = NULL;
 307        struct argv_array make_script_args = ARGV_ARRAY_INIT;
 308        struct todo_list todo_list = TODO_LIST_INIT;
 309        struct replay_opts replay = get_replay_opts(opts);
 310        struct string_list commands = STRING_LIST_INIT_DUP;
 311
 312        if (prepare_branch_to_be_rebased(the_repository, &replay,
 313                                         opts->switch_to))
 314                return -1;
 315
 316        if (get_revision_ranges(opts->upstream, opts->onto, &head_hash,
 317                                &revisions, &shortrevisions))
 318                return -1;
 319
 320        if (init_basic_state(&replay,
 321                             opts->head_name ? opts->head_name : "detached HEAD",
 322                             opts->onto, head_hash)) {
 323                free(revisions);
 324                free(shortrevisions);
 325
 326                return -1;
 327        }
 328
 329        if (!opts->upstream && opts->squash_onto)
 330                write_file(path_squash_onto(), "%s\n",
 331                           oid_to_hex(opts->squash_onto));
 332
 333        argv_array_pushl(&make_script_args, "", revisions, NULL);
 334        if (opts->restrict_revision)
 335                argv_array_push(&make_script_args,
 336                                oid_to_hex(&opts->restrict_revision->object.oid));
 337
 338        ret = sequencer_make_script(the_repository, &todo_list.buf,
 339                                    make_script_args.argc, make_script_args.argv,
 340                                    flags);
 341
 342        if (ret)
 343                error(_("could not generate todo list"));
 344        else {
 345                discard_cache();
 346                if (todo_list_parse_insn_buffer(the_repository, todo_list.buf.buf,
 347                                                &todo_list))
 348                        BUG("unusable todo list");
 349
 350                split_exec_commands(opts->cmd, &commands);
 351                ret = complete_action(the_repository, &replay, flags,
 352                        shortrevisions, opts->onto_name, opts->onto, head_hash,
 353                        &commands, opts->autosquash, &todo_list);
 354        }
 355
 356        string_list_clear(&commands, 0);
 357        free(revisions);
 358        free(shortrevisions);
 359        todo_list_release(&todo_list);
 360        argv_array_clear(&make_script_args);
 361
 362        return ret;
 363}
 364
 365static int run_rebase_interactive(struct rebase_options *opts,
 366                                  enum action command)
 367{
 368        unsigned flags = 0;
 369        int abbreviate_commands = 0, ret = 0;
 370
 371        git_config_get_bool("rebase.abbreviatecommands", &abbreviate_commands);
 372
 373        flags |= opts->keep_empty ? TODO_LIST_KEEP_EMPTY : 0;
 374        flags |= abbreviate_commands ? TODO_LIST_ABBREVIATE_CMDS : 0;
 375        flags |= opts->rebase_merges ? TODO_LIST_REBASE_MERGES : 0;
 376        flags |= opts->rebase_cousins > 0 ? TODO_LIST_REBASE_COUSINS : 0;
 377        flags |= command == ACTION_SHORTEN_OIDS ? TODO_LIST_SHORTEN_IDS : 0;
 378
 379        switch (command) {
 380        case ACTION_NONE: {
 381                if (!opts->onto && !opts->upstream)
 382                        die(_("a base commit must be provided with --upstream or --onto"));
 383
 384                ret = do_interactive_rebase(opts, flags);
 385                break;
 386        }
 387        case ACTION_SKIP: {
 388                struct string_list merge_rr = STRING_LIST_INIT_DUP;
 389
 390                rerere_clear(the_repository, &merge_rr);
 391        }
 392                /* fallthrough */
 393        case ACTION_CONTINUE: {
 394                struct replay_opts replay_opts = get_replay_opts(opts);
 395
 396                ret = sequencer_continue(the_repository, &replay_opts);
 397                break;
 398        }
 399        case ACTION_EDIT_TODO:
 400                ret = edit_todo_file(flags);
 401                break;
 402        case ACTION_SHOW_CURRENT_PATCH: {
 403                struct child_process cmd = CHILD_PROCESS_INIT;
 404
 405                cmd.git_cmd = 1;
 406                argv_array_pushl(&cmd.args, "show", "REBASE_HEAD", "--", NULL);
 407                ret = run_command(&cmd);
 408
 409                break;
 410        }
 411        case ACTION_SHORTEN_OIDS:
 412        case ACTION_EXPAND_OIDS:
 413                ret = transform_todo_file(flags);
 414                break;
 415        case ACTION_CHECK_TODO_LIST:
 416                ret = check_todo_list_from_file(the_repository);
 417                break;
 418        case ACTION_REARRANGE_SQUASH:
 419                ret = rearrange_squash_in_todo_file();
 420                break;
 421        case ACTION_ADD_EXEC: {
 422                struct string_list commands = STRING_LIST_INIT_DUP;
 423
 424                split_exec_commands(opts->cmd, &commands);
 425                ret = add_exec_commands(&commands);
 426                string_list_clear(&commands, 0);
 427                break;
 428        }
 429        default:
 430                BUG("invalid command '%d'", command);
 431        }
 432
 433        return ret;
 434}
 435
 436static const char * const builtin_rebase_interactive_usage[] = {
 437        N_("git rebase--interactive [<options>]"),
 438        NULL
 439};
 440
 441int cmd_rebase__interactive(int argc, const char **argv, const char *prefix)
 442{
 443        struct rebase_options opts = REBASE_OPTIONS_INIT;
 444        struct object_id squash_onto = null_oid;
 445        enum action command = ACTION_NONE;
 446        struct option options[] = {
 447                OPT_NEGBIT(0, "ff", &opts.flags, N_("allow fast-forward"),
 448                           REBASE_FORCE),
 449                OPT_BOOL(0, "keep-empty", &opts.keep_empty, N_("keep empty commits")),
 450                OPT_BOOL(0, "allow-empty-message", &opts.allow_empty_message,
 451                         N_("allow commits with empty messages")),
 452                OPT_BOOL(0, "rebase-merges", &opts.rebase_merges, N_("rebase merge commits")),
 453                OPT_BOOL(0, "rebase-cousins", &opts.rebase_cousins,
 454                         N_("keep original branch points of cousins")),
 455                OPT_BOOL(0, "autosquash", &opts.autosquash,
 456                         N_("move commits that begin with squash!/fixup!")),
 457                OPT_BOOL(0, "signoff", &opts.signoff, N_("sign commits")),
 458                OPT_BIT('v', "verbose", &opts.flags,
 459                        N_("display a diffstat of what changed upstream"),
 460                        REBASE_NO_QUIET | REBASE_VERBOSE | REBASE_DIFFSTAT),
 461                OPT_CMDMODE(0, "continue", &command, N_("continue rebase"),
 462                            ACTION_CONTINUE),
 463                OPT_CMDMODE(0, "skip", &command, N_("skip commit"), ACTION_SKIP),
 464                OPT_CMDMODE(0, "edit-todo", &command, N_("edit the todo list"),
 465                            ACTION_EDIT_TODO),
 466                OPT_CMDMODE(0, "show-current-patch", &command, N_("show the current patch"),
 467                            ACTION_SHOW_CURRENT_PATCH),
 468                OPT_CMDMODE(0, "shorten-ids", &command,
 469                        N_("shorten commit ids in the todo list"), ACTION_SHORTEN_OIDS),
 470                OPT_CMDMODE(0, "expand-ids", &command,
 471                        N_("expand commit ids in the todo list"), ACTION_EXPAND_OIDS),
 472                OPT_CMDMODE(0, "check-todo-list", &command,
 473                        N_("check the todo list"), ACTION_CHECK_TODO_LIST),
 474                OPT_CMDMODE(0, "rearrange-squash", &command,
 475                        N_("rearrange fixup/squash lines"), ACTION_REARRANGE_SQUASH),
 476                OPT_CMDMODE(0, "add-exec-commands", &command,
 477                        N_("insert exec commands in todo list"), ACTION_ADD_EXEC),
 478                { OPTION_CALLBACK, 0, "onto", &opts.onto, N_("onto"), N_("onto"),
 479                  PARSE_OPT_NONEG, parse_opt_commit, 0 },
 480                { OPTION_CALLBACK, 0, "restrict-revision", &opts.restrict_revision,
 481                  N_("restrict-revision"), N_("restrict revision"),
 482                  PARSE_OPT_NONEG, parse_opt_commit, 0 },
 483                { OPTION_CALLBACK, 0, "squash-onto", &squash_onto, N_("squash-onto"),
 484                  N_("squash onto"), PARSE_OPT_NONEG, parse_opt_object_id, 0 },
 485                { OPTION_CALLBACK, 0, "upstream", &opts.upstream, N_("upstream"),
 486                  N_("the upstream commit"), PARSE_OPT_NONEG, parse_opt_commit,
 487                  0 },
 488                OPT_STRING(0, "head-name", &opts.head_name, N_("head-name"), N_("head name")),
 489                { OPTION_STRING, 'S', "gpg-sign", &opts.gpg_sign_opt, N_("key-id"),
 490                        N_("GPG-sign commits"),
 491                        PARSE_OPT_OPTARG, NULL, (intptr_t) "" },
 492                OPT_STRING(0, "strategy", &opts.strategy, N_("strategy"),
 493                           N_("rebase strategy")),
 494                OPT_STRING(0, "strategy-opts", &opts.strategy_opts, N_("strategy-opts"),
 495                           N_("strategy options")),
 496                OPT_STRING(0, "switch-to", &opts.switch_to, N_("switch-to"),
 497                           N_("the branch or commit to checkout")),
 498                OPT_STRING(0, "onto-name", &opts.onto_name, N_("onto-name"), N_("onto name")),
 499                OPT_STRING(0, "cmd", &opts.cmd, N_("cmd"), N_("the command to run")),
 500                OPT_RERERE_AUTOUPDATE(&opts.allow_rerere_autoupdate),
 501                OPT_BOOL(0, "reschedule-failed-exec", &opts.reschedule_failed_exec,
 502                         N_("automatically re-schedule any `exec` that fails")),
 503                OPT_END()
 504        };
 505
 506        opts.rebase_cousins = -1;
 507
 508        if (argc == 1)
 509                usage_with_options(builtin_rebase_interactive_usage, options);
 510
 511        argc = parse_options(argc, argv, prefix, options,
 512                        builtin_rebase_interactive_usage, PARSE_OPT_KEEP_ARGV0);
 513
 514        if (!is_null_oid(&squash_onto))
 515                opts.squash_onto = &squash_onto;
 516
 517        if (opts.rebase_cousins >= 0 && !opts.rebase_merges)
 518                warning(_("--[no-]rebase-cousins has no effect without "
 519                          "--rebase-merges"));
 520
 521        return !!run_rebase_interactive(&opts, command);
 522}
 523
 524static int is_interactive(struct rebase_options *opts)
 525{
 526        return opts->type == REBASE_INTERACTIVE ||
 527                opts->type == REBASE_PRESERVE_MERGES;
 528}
 529
 530static void imply_interactive(struct rebase_options *opts, const char *option)
 531{
 532        switch (opts->type) {
 533        case REBASE_AM:
 534                die(_("%s requires an interactive rebase"), option);
 535                break;
 536        case REBASE_INTERACTIVE:
 537        case REBASE_PRESERVE_MERGES:
 538                break;
 539        case REBASE_MERGE:
 540                /* we now implement --merge via --interactive */
 541        default:
 542                opts->type = REBASE_INTERACTIVE; /* implied */
 543                break;
 544        }
 545}
 546
 547/* Returns the filename prefixed by the state_dir */
 548static const char *state_dir_path(const char *filename, struct rebase_options *opts)
 549{
 550        static struct strbuf path = STRBUF_INIT;
 551        static size_t prefix_len;
 552
 553        if (!prefix_len) {
 554                strbuf_addf(&path, "%s/", opts->state_dir);
 555                prefix_len = path.len;
 556        }
 557
 558        strbuf_setlen(&path, prefix_len);
 559        strbuf_addstr(&path, filename);
 560        return path.buf;
 561}
 562
 563/* Read one file, then strip line endings */
 564static int read_one(const char *path, struct strbuf *buf)
 565{
 566        if (strbuf_read_file(buf, path, 0) < 0)
 567                return error_errno(_("could not read '%s'"), path);
 568        strbuf_trim_trailing_newline(buf);
 569        return 0;
 570}
 571
 572/* Initialize the rebase options from the state directory. */
 573static int read_basic_state(struct rebase_options *opts)
 574{
 575        struct strbuf head_name = STRBUF_INIT;
 576        struct strbuf buf = STRBUF_INIT;
 577        struct object_id oid;
 578
 579        if (read_one(state_dir_path("head-name", opts), &head_name) ||
 580            read_one(state_dir_path("onto", opts), &buf))
 581                return -1;
 582        opts->head_name = starts_with(head_name.buf, "refs/") ?
 583                xstrdup(head_name.buf) : NULL;
 584        strbuf_release(&head_name);
 585        if (get_oid(buf.buf, &oid))
 586                return error(_("could not get 'onto': '%s'"), buf.buf);
 587        opts->onto = lookup_commit_or_die(&oid, buf.buf);
 588
 589        /*
 590         * We always write to orig-head, but interactive rebase used to write to
 591         * head. Fall back to reading from head to cover for the case that the
 592         * user upgraded git with an ongoing interactive rebase.
 593         */
 594        strbuf_reset(&buf);
 595        if (file_exists(state_dir_path("orig-head", opts))) {
 596                if (read_one(state_dir_path("orig-head", opts), &buf))
 597                        return -1;
 598        } else if (read_one(state_dir_path("head", opts), &buf))
 599                return -1;
 600        if (get_oid(buf.buf, &opts->orig_head))
 601                return error(_("invalid orig-head: '%s'"), buf.buf);
 602
 603        if (file_exists(state_dir_path("quiet", opts)))
 604                opts->flags &= ~REBASE_NO_QUIET;
 605        else
 606                opts->flags |= REBASE_NO_QUIET;
 607
 608        if (file_exists(state_dir_path("verbose", opts)))
 609                opts->flags |= REBASE_VERBOSE;
 610
 611        if (file_exists(state_dir_path("signoff", opts))) {
 612                opts->signoff = 1;
 613                opts->flags |= REBASE_FORCE;
 614        }
 615
 616        if (file_exists(state_dir_path("allow_rerere_autoupdate", opts))) {
 617                strbuf_reset(&buf);
 618                if (read_one(state_dir_path("allow_rerere_autoupdate", opts),
 619                            &buf))
 620                        return -1;
 621                if (!strcmp(buf.buf, "--rerere-autoupdate"))
 622                        opts->allow_rerere_autoupdate = RERERE_AUTOUPDATE;
 623                else if (!strcmp(buf.buf, "--no-rerere-autoupdate"))
 624                        opts->allow_rerere_autoupdate = RERERE_NOAUTOUPDATE;
 625                else
 626                        warning(_("ignoring invalid allow_rerere_autoupdate: "
 627                                  "'%s'"), buf.buf);
 628        }
 629
 630        if (file_exists(state_dir_path("gpg_sign_opt", opts))) {
 631                strbuf_reset(&buf);
 632                if (read_one(state_dir_path("gpg_sign_opt", opts),
 633                            &buf))
 634                        return -1;
 635                free(opts->gpg_sign_opt);
 636                opts->gpg_sign_opt = xstrdup(buf.buf);
 637        }
 638
 639        if (file_exists(state_dir_path("strategy", opts))) {
 640                strbuf_reset(&buf);
 641                if (read_one(state_dir_path("strategy", opts), &buf))
 642                        return -1;
 643                free(opts->strategy);
 644                opts->strategy = xstrdup(buf.buf);
 645        }
 646
 647        if (file_exists(state_dir_path("strategy_opts", opts))) {
 648                strbuf_reset(&buf);
 649                if (read_one(state_dir_path("strategy_opts", opts), &buf))
 650                        return -1;
 651                free(opts->strategy_opts);
 652                opts->strategy_opts = xstrdup(buf.buf);
 653        }
 654
 655        strbuf_release(&buf);
 656
 657        return 0;
 658}
 659
 660static int rebase_write_basic_state(struct rebase_options *opts)
 661{
 662        write_file(state_dir_path("head-name", opts), "%s",
 663                   opts->head_name ? opts->head_name : "detached HEAD");
 664        write_file(state_dir_path("onto", opts), "%s",
 665                   opts->onto ? oid_to_hex(&opts->onto->object.oid) : "");
 666        write_file(state_dir_path("orig-head", opts), "%s",
 667                   oid_to_hex(&opts->orig_head));
 668        write_file(state_dir_path("quiet", opts), "%s",
 669                   opts->flags & REBASE_NO_QUIET ? "" : "t");
 670        if (opts->flags & REBASE_VERBOSE)
 671                write_file(state_dir_path("verbose", opts), "%s", "");
 672        if (opts->strategy)
 673                write_file(state_dir_path("strategy", opts), "%s",
 674                           opts->strategy);
 675        if (opts->strategy_opts)
 676                write_file(state_dir_path("strategy_opts", opts), "%s",
 677                           opts->strategy_opts);
 678        if (opts->allow_rerere_autoupdate > 0)
 679                write_file(state_dir_path("allow_rerere_autoupdate", opts),
 680                           "-%s-rerere-autoupdate",
 681                           opts->allow_rerere_autoupdate == RERERE_AUTOUPDATE ?
 682                                "" : "-no");
 683        if (opts->gpg_sign_opt)
 684                write_file(state_dir_path("gpg_sign_opt", opts), "%s",
 685                           opts->gpg_sign_opt);
 686        if (opts->signoff)
 687                write_file(state_dir_path("strategy", opts), "--signoff");
 688
 689        return 0;
 690}
 691
 692static int apply_autostash(struct rebase_options *opts)
 693{
 694        const char *path = state_dir_path("autostash", opts);
 695        struct strbuf autostash = STRBUF_INIT;
 696        struct child_process stash_apply = CHILD_PROCESS_INIT;
 697
 698        if (!file_exists(path))
 699                return 0;
 700
 701        if (read_one(path, &autostash))
 702                return error(_("Could not read '%s'"), path);
 703        /* Ensure that the hash is not mistaken for a number */
 704        strbuf_addstr(&autostash, "^0");
 705        argv_array_pushl(&stash_apply.args,
 706                         "stash", "apply", autostash.buf, NULL);
 707        stash_apply.git_cmd = 1;
 708        stash_apply.no_stderr = stash_apply.no_stdout =
 709                stash_apply.no_stdin = 1;
 710        if (!run_command(&stash_apply))
 711                printf(_("Applied autostash.\n"));
 712        else {
 713                struct argv_array args = ARGV_ARRAY_INIT;
 714                int res = 0;
 715
 716                argv_array_pushl(&args,
 717                                 "stash", "store", "-m", "autostash", "-q",
 718                                 autostash.buf, NULL);
 719                if (run_command_v_opt(args.argv, RUN_GIT_CMD))
 720                        res = error(_("Cannot store %s"), autostash.buf);
 721                argv_array_clear(&args);
 722                strbuf_release(&autostash);
 723                if (res)
 724                        return res;
 725
 726                fprintf(stderr,
 727                        _("Applying autostash resulted in conflicts.\n"
 728                          "Your changes are safe in the stash.\n"
 729                          "You can run \"git stash pop\" or \"git stash drop\" "
 730                          "at any time.\n"));
 731        }
 732
 733        strbuf_release(&autostash);
 734        return 0;
 735}
 736
 737static int finish_rebase(struct rebase_options *opts)
 738{
 739        struct strbuf dir = STRBUF_INIT;
 740        const char *argv_gc_auto[] = { "gc", "--auto", NULL };
 741
 742        delete_ref(NULL, "REBASE_HEAD", NULL, REF_NO_DEREF);
 743        apply_autostash(opts);
 744        close_all_packs(the_repository->objects);
 745        /*
 746         * We ignore errors in 'gc --auto', since the
 747         * user should see them.
 748         */
 749        run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
 750        strbuf_addstr(&dir, opts->state_dir);
 751        remove_dir_recursively(&dir, 0);
 752        strbuf_release(&dir);
 753
 754        return 0;
 755}
 756
 757static struct commit *peel_committish(const char *name)
 758{
 759        struct object *obj;
 760        struct object_id oid;
 761
 762        if (get_oid(name, &oid))
 763                return NULL;
 764        obj = parse_object(the_repository, &oid);
 765        return (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
 766}
 767
 768static void add_var(struct strbuf *buf, const char *name, const char *value)
 769{
 770        if (!value)
 771                strbuf_addf(buf, "unset %s; ", name);
 772        else {
 773                strbuf_addf(buf, "%s=", name);
 774                sq_quote_buf(buf, value);
 775                strbuf_addstr(buf, "; ");
 776        }
 777}
 778
 779#define GIT_REFLOG_ACTION_ENVIRONMENT "GIT_REFLOG_ACTION"
 780
 781#define RESET_HEAD_DETACH (1<<0)
 782#define RESET_HEAD_HARD (1<<1)
 783#define RESET_HEAD_RUN_POST_CHECKOUT_HOOK (1<<2)
 784#define RESET_HEAD_REFS_ONLY (1<<3)
 785#define RESET_ORIG_HEAD (1<<4)
 786
 787static int reset_head(struct object_id *oid, const char *action,
 788                      const char *switch_to_branch, unsigned flags,
 789                      const char *reflog_orig_head, const char *reflog_head)
 790{
 791        unsigned detach_head = flags & RESET_HEAD_DETACH;
 792        unsigned reset_hard = flags & RESET_HEAD_HARD;
 793        unsigned run_hook = flags & RESET_HEAD_RUN_POST_CHECKOUT_HOOK;
 794        unsigned refs_only = flags & RESET_HEAD_REFS_ONLY;
 795        unsigned update_orig_head = flags & RESET_ORIG_HEAD;
 796        struct object_id head_oid;
 797        struct tree_desc desc[2] = { { NULL }, { NULL } };
 798        struct lock_file lock = LOCK_INIT;
 799        struct unpack_trees_options unpack_tree_opts;
 800        struct tree *tree;
 801        const char *reflog_action;
 802        struct strbuf msg = STRBUF_INIT;
 803        size_t prefix_len;
 804        struct object_id *orig = NULL, oid_orig,
 805                *old_orig = NULL, oid_old_orig;
 806        int ret = 0, nr = 0;
 807
 808        if (switch_to_branch && !starts_with(switch_to_branch, "refs/"))
 809                BUG("Not a fully qualified branch: '%s'", switch_to_branch);
 810
 811        if (!refs_only && hold_locked_index(&lock, LOCK_REPORT_ON_ERROR) < 0) {
 812                ret = -1;
 813                goto leave_reset_head;
 814        }
 815
 816        if ((!oid || !reset_hard) && get_oid("HEAD", &head_oid)) {
 817                ret = error(_("could not determine HEAD revision"));
 818                goto leave_reset_head;
 819        }
 820
 821        if (!oid)
 822                oid = &head_oid;
 823
 824        if (refs_only)
 825                goto reset_head_refs;
 826
 827        memset(&unpack_tree_opts, 0, sizeof(unpack_tree_opts));
 828        setup_unpack_trees_porcelain(&unpack_tree_opts, action);
 829        unpack_tree_opts.head_idx = 1;
 830        unpack_tree_opts.src_index = the_repository->index;
 831        unpack_tree_opts.dst_index = the_repository->index;
 832        unpack_tree_opts.fn = reset_hard ? oneway_merge : twoway_merge;
 833        unpack_tree_opts.update = 1;
 834        unpack_tree_opts.merge = 1;
 835        if (!detach_head)
 836                unpack_tree_opts.reset = 1;
 837
 838        if (repo_read_index_unmerged(the_repository) < 0) {
 839                ret = error(_("could not read index"));
 840                goto leave_reset_head;
 841        }
 842
 843        if (!reset_hard && !fill_tree_descriptor(&desc[nr++], &head_oid)) {
 844                ret = error(_("failed to find tree of %s"),
 845                            oid_to_hex(&head_oid));
 846                goto leave_reset_head;
 847        }
 848
 849        if (!fill_tree_descriptor(&desc[nr++], oid)) {
 850                ret = error(_("failed to find tree of %s"), oid_to_hex(oid));
 851                goto leave_reset_head;
 852        }
 853
 854        if (unpack_trees(nr, desc, &unpack_tree_opts)) {
 855                ret = -1;
 856                goto leave_reset_head;
 857        }
 858
 859        tree = parse_tree_indirect(oid);
 860        prime_cache_tree(the_repository, the_repository->index, tree);
 861
 862        if (write_locked_index(the_repository->index, &lock, COMMIT_LOCK) < 0) {
 863                ret = error(_("could not write index"));
 864                goto leave_reset_head;
 865        }
 866
 867reset_head_refs:
 868        reflog_action = getenv(GIT_REFLOG_ACTION_ENVIRONMENT);
 869        strbuf_addf(&msg, "%s: ", reflog_action ? reflog_action : "rebase");
 870        prefix_len = msg.len;
 871
 872        if (update_orig_head) {
 873                if (!get_oid("ORIG_HEAD", &oid_old_orig))
 874                        old_orig = &oid_old_orig;
 875                if (!get_oid("HEAD", &oid_orig)) {
 876                        orig = &oid_orig;
 877                        if (!reflog_orig_head) {
 878                                strbuf_addstr(&msg, "updating ORIG_HEAD");
 879                                reflog_orig_head = msg.buf;
 880                        }
 881                        update_ref(reflog_orig_head, "ORIG_HEAD", orig,
 882                                   old_orig, 0, UPDATE_REFS_MSG_ON_ERR);
 883                } else if (old_orig)
 884                        delete_ref(NULL, "ORIG_HEAD", old_orig, 0);
 885        }
 886
 887        if (!reflog_head) {
 888                strbuf_setlen(&msg, prefix_len);
 889                strbuf_addstr(&msg, "updating HEAD");
 890                reflog_head = msg.buf;
 891        }
 892        if (!switch_to_branch)
 893                ret = update_ref(reflog_head, "HEAD", oid, orig,
 894                                 detach_head ? REF_NO_DEREF : 0,
 895                                 UPDATE_REFS_MSG_ON_ERR);
 896        else {
 897                ret = update_ref(reflog_head, switch_to_branch, oid,
 898                                 NULL, 0, UPDATE_REFS_MSG_ON_ERR);
 899                if (!ret)
 900                        ret = create_symref("HEAD", switch_to_branch,
 901                                            reflog_head);
 902        }
 903        if (run_hook)
 904                run_hook_le(NULL, "post-checkout",
 905                            oid_to_hex(orig ? orig : &null_oid),
 906                            oid_to_hex(oid), "1", NULL);
 907
 908leave_reset_head:
 909        strbuf_release(&msg);
 910        rollback_lock_file(&lock);
 911        while (nr)
 912                free((void *)desc[--nr].buffer);
 913        return ret;
 914}
 915
 916static int move_to_original_branch(struct rebase_options *opts)
 917{
 918        struct strbuf orig_head_reflog = STRBUF_INIT, head_reflog = STRBUF_INIT;
 919        int ret;
 920
 921        if (!opts->head_name)
 922                return 0; /* nothing to move back to */
 923
 924        if (!opts->onto)
 925                BUG("move_to_original_branch without onto");
 926
 927        strbuf_addf(&orig_head_reflog, "rebase finished: %s onto %s",
 928                    opts->head_name, oid_to_hex(&opts->onto->object.oid));
 929        strbuf_addf(&head_reflog, "rebase finished: returning to %s",
 930                    opts->head_name);
 931        ret = reset_head(NULL, "", opts->head_name, RESET_HEAD_REFS_ONLY,
 932                         orig_head_reflog.buf, head_reflog.buf);
 933
 934        strbuf_release(&orig_head_reflog);
 935        strbuf_release(&head_reflog);
 936        return ret;
 937}
 938
 939static const char *resolvemsg =
 940N_("Resolve all conflicts manually, mark them as resolved with\n"
 941"\"git add/rm <conflicted_files>\", then run \"git rebase --continue\".\n"
 942"You can instead skip this commit: run \"git rebase --skip\".\n"
 943"To abort and get back to the state before \"git rebase\", run "
 944"\"git rebase --abort\".");
 945
 946static int run_am(struct rebase_options *opts)
 947{
 948        struct child_process am = CHILD_PROCESS_INIT;
 949        struct child_process format_patch = CHILD_PROCESS_INIT;
 950        struct strbuf revisions = STRBUF_INIT;
 951        int status;
 952        char *rebased_patches;
 953
 954        am.git_cmd = 1;
 955        argv_array_push(&am.args, "am");
 956
 957        if (opts->action && !strcmp("continue", opts->action)) {
 958                argv_array_push(&am.args, "--resolved");
 959                argv_array_pushf(&am.args, "--resolvemsg=%s", resolvemsg);
 960                if (opts->gpg_sign_opt)
 961                        argv_array_push(&am.args, opts->gpg_sign_opt);
 962                status = run_command(&am);
 963                if (status)
 964                        return status;
 965
 966                return move_to_original_branch(opts);
 967        }
 968        if (opts->action && !strcmp("skip", opts->action)) {
 969                argv_array_push(&am.args, "--skip");
 970                argv_array_pushf(&am.args, "--resolvemsg=%s", resolvemsg);
 971                status = run_command(&am);
 972                if (status)
 973                        return status;
 974
 975                return move_to_original_branch(opts);
 976        }
 977        if (opts->action && !strcmp("show-current-patch", opts->action)) {
 978                argv_array_push(&am.args, "--show-current-patch");
 979                return run_command(&am);
 980        }
 981
 982        strbuf_addf(&revisions, "%s...%s",
 983                    oid_to_hex(opts->root ?
 984                               /* this is now equivalent to !opts->upstream */
 985                               &opts->onto->object.oid :
 986                               &opts->upstream->object.oid),
 987                    oid_to_hex(&opts->orig_head));
 988
 989        rebased_patches = xstrdup(git_path("rebased-patches"));
 990        format_patch.out = open(rebased_patches,
 991                                O_WRONLY | O_CREAT | O_TRUNC, 0666);
 992        if (format_patch.out < 0) {
 993                status = error_errno(_("could not open '%s' for writing"),
 994                                     rebased_patches);
 995                free(rebased_patches);
 996                argv_array_clear(&am.args);
 997                return status;
 998        }
 999
1000        format_patch.git_cmd = 1;
1001        argv_array_pushl(&format_patch.args, "format-patch", "-k", "--stdout",
1002                         "--full-index", "--cherry-pick", "--right-only",
1003                         "--src-prefix=a/", "--dst-prefix=b/", "--no-renames",
1004                         "--no-cover-letter", "--pretty=mboxrd", "--topo-order", NULL);
1005        if (opts->git_format_patch_opt.len)
1006                argv_array_split(&format_patch.args,
1007                                 opts->git_format_patch_opt.buf);
1008        argv_array_push(&format_patch.args, revisions.buf);
1009        if (opts->restrict_revision)
1010                argv_array_pushf(&format_patch.args, "^%s",
1011                                 oid_to_hex(&opts->restrict_revision->object.oid));
1012
1013        status = run_command(&format_patch);
1014        if (status) {
1015                unlink(rebased_patches);
1016                free(rebased_patches);
1017                argv_array_clear(&am.args);
1018
1019                reset_head(&opts->orig_head, "checkout", opts->head_name, 0,
1020                           "HEAD", NULL);
1021                error(_("\ngit encountered an error while preparing the "
1022                        "patches to replay\n"
1023                        "these revisions:\n"
1024                        "\n    %s\n\n"
1025                        "As a result, git cannot rebase them."),
1026                      opts->revisions);
1027
1028                strbuf_release(&revisions);
1029                return status;
1030        }
1031        strbuf_release(&revisions);
1032
1033        am.in = open(rebased_patches, O_RDONLY);
1034        if (am.in < 0) {
1035                status = error_errno(_("could not open '%s' for reading"),
1036                                     rebased_patches);
1037                free(rebased_patches);
1038                argv_array_clear(&am.args);
1039                return status;
1040        }
1041
1042        argv_array_pushv(&am.args, opts->git_am_opts.argv);
1043        argv_array_push(&am.args, "--rebasing");
1044        argv_array_pushf(&am.args, "--resolvemsg=%s", resolvemsg);
1045        argv_array_push(&am.args, "--patch-format=mboxrd");
1046        if (opts->allow_rerere_autoupdate == RERERE_AUTOUPDATE)
1047                argv_array_push(&am.args, "--rerere-autoupdate");
1048        else if (opts->allow_rerere_autoupdate == RERERE_NOAUTOUPDATE)
1049                argv_array_push(&am.args, "--no-rerere-autoupdate");
1050        if (opts->gpg_sign_opt)
1051                argv_array_push(&am.args, opts->gpg_sign_opt);
1052        status = run_command(&am);
1053        unlink(rebased_patches);
1054        free(rebased_patches);
1055
1056        if (!status) {
1057                return move_to_original_branch(opts);
1058        }
1059
1060        if (is_directory(opts->state_dir))
1061                rebase_write_basic_state(opts);
1062
1063        return status;
1064}
1065
1066static int run_specific_rebase(struct rebase_options *opts, enum action action)
1067{
1068        const char *argv[] = { NULL, NULL };
1069        struct strbuf script_snippet = STRBUF_INIT, buf = STRBUF_INIT;
1070        int status;
1071        const char *backend, *backend_func;
1072
1073        if (opts->type == REBASE_INTERACTIVE) {
1074                /* Run builtin interactive rebase */
1075                setenv("GIT_CHERRY_PICK_HELP", resolvemsg, 1);
1076                if (!(opts->flags & REBASE_INTERACTIVE_EXPLICIT)) {
1077                        setenv("GIT_SEQUENCE_EDITOR", ":", 1);
1078                        opts->autosquash = 0;
1079                }
1080                if (opts->gpg_sign_opt) {
1081                        /* remove the leading "-S" */
1082                        char *tmp = xstrdup(opts->gpg_sign_opt + 2);
1083                        free(opts->gpg_sign_opt);
1084                        opts->gpg_sign_opt = tmp;
1085                }
1086
1087                status = run_rebase_interactive(opts, action);
1088                goto finished_rebase;
1089        }
1090
1091        if (opts->type == REBASE_AM) {
1092                status = run_am(opts);
1093                goto finished_rebase;
1094        }
1095
1096        add_var(&script_snippet, "GIT_DIR", absolute_path(get_git_dir()));
1097        add_var(&script_snippet, "state_dir", opts->state_dir);
1098
1099        add_var(&script_snippet, "upstream_name", opts->upstream_name);
1100        add_var(&script_snippet, "upstream", opts->upstream ?
1101                oid_to_hex(&opts->upstream->object.oid) : NULL);
1102        add_var(&script_snippet, "head_name",
1103                opts->head_name ? opts->head_name : "detached HEAD");
1104        add_var(&script_snippet, "orig_head", oid_to_hex(&opts->orig_head));
1105        add_var(&script_snippet, "onto", opts->onto ?
1106                oid_to_hex(&opts->onto->object.oid) : NULL);
1107        add_var(&script_snippet, "onto_name", opts->onto_name);
1108        add_var(&script_snippet, "revisions", opts->revisions);
1109        add_var(&script_snippet, "restrict_revision", opts->restrict_revision ?
1110                oid_to_hex(&opts->restrict_revision->object.oid) : NULL);
1111        add_var(&script_snippet, "GIT_QUIET",
1112                opts->flags & REBASE_NO_QUIET ? "" : "t");
1113        sq_quote_argv_pretty(&buf, opts->git_am_opts.argv);
1114        add_var(&script_snippet, "git_am_opt", buf.buf);
1115        strbuf_release(&buf);
1116        add_var(&script_snippet, "verbose",
1117                opts->flags & REBASE_VERBOSE ? "t" : "");
1118        add_var(&script_snippet, "diffstat",
1119                opts->flags & REBASE_DIFFSTAT ? "t" : "");
1120        add_var(&script_snippet, "force_rebase",
1121                opts->flags & REBASE_FORCE ? "t" : "");
1122        if (opts->switch_to)
1123                add_var(&script_snippet, "switch_to", opts->switch_to);
1124        add_var(&script_snippet, "action", opts->action ? opts->action : "");
1125        add_var(&script_snippet, "signoff", opts->signoff ? "--signoff" : "");
1126        add_var(&script_snippet, "allow_rerere_autoupdate",
1127                opts->allow_rerere_autoupdate ?
1128                        opts->allow_rerere_autoupdate == RERERE_AUTOUPDATE ?
1129                        "--rerere-autoupdate" : "--no-rerere-autoupdate" : "");
1130        add_var(&script_snippet, "keep_empty", opts->keep_empty ? "yes" : "");
1131        add_var(&script_snippet, "autosquash", opts->autosquash ? "t" : "");
1132        add_var(&script_snippet, "gpg_sign_opt", opts->gpg_sign_opt);
1133        add_var(&script_snippet, "cmd", opts->cmd);
1134        add_var(&script_snippet, "allow_empty_message",
1135                opts->allow_empty_message ?  "--allow-empty-message" : "");
1136        add_var(&script_snippet, "rebase_merges",
1137                opts->rebase_merges ? "t" : "");
1138        add_var(&script_snippet, "rebase_cousins",
1139                opts->rebase_cousins ? "t" : "");
1140        add_var(&script_snippet, "strategy", opts->strategy);
1141        add_var(&script_snippet, "strategy_opts", opts->strategy_opts);
1142        add_var(&script_snippet, "rebase_root", opts->root ? "t" : "");
1143        add_var(&script_snippet, "squash_onto",
1144                opts->squash_onto ? oid_to_hex(opts->squash_onto) : "");
1145        add_var(&script_snippet, "git_format_patch_opt",
1146                opts->git_format_patch_opt.buf);
1147
1148        if (is_interactive(opts) &&
1149            !(opts->flags & REBASE_INTERACTIVE_EXPLICIT)) {
1150                strbuf_addstr(&script_snippet,
1151                              "GIT_SEQUENCE_EDITOR=:; export GIT_SEQUENCE_EDITOR; ");
1152                opts->autosquash = 0;
1153        }
1154
1155        switch (opts->type) {
1156        case REBASE_PRESERVE_MERGES:
1157                backend = "git-rebase--preserve-merges";
1158                backend_func = "git_rebase__preserve_merges";
1159                break;
1160        default:
1161                BUG("Unhandled rebase type %d", opts->type);
1162                break;
1163        }
1164
1165        strbuf_addf(&script_snippet,
1166                    ". git-sh-setup && . %s && %s", backend, backend_func);
1167        argv[0] = script_snippet.buf;
1168
1169        status = run_command_v_opt(argv, RUN_USING_SHELL);
1170finished_rebase:
1171        if (opts->dont_finish_rebase)
1172                ; /* do nothing */
1173        else if (opts->type == REBASE_INTERACTIVE)
1174                ; /* interactive rebase cleans up after itself */
1175        else if (status == 0) {
1176                if (!file_exists(state_dir_path("stopped-sha", opts)))
1177                        finish_rebase(opts);
1178        } else if (status == 2) {
1179                struct strbuf dir = STRBUF_INIT;
1180
1181                apply_autostash(opts);
1182                strbuf_addstr(&dir, opts->state_dir);
1183                remove_dir_recursively(&dir, 0);
1184                strbuf_release(&dir);
1185                die("Nothing to do");
1186        }
1187
1188        strbuf_release(&script_snippet);
1189
1190        return status ? -1 : 0;
1191}
1192
1193static int rebase_config(const char *var, const char *value, void *data)
1194{
1195        struct rebase_options *opts = data;
1196
1197        if (!strcmp(var, "rebase.stat")) {
1198                if (git_config_bool(var, value))
1199                        opts->flags |= REBASE_DIFFSTAT;
1200                else
1201                        opts->flags &= ~REBASE_DIFFSTAT;
1202                return 0;
1203        }
1204
1205        if (!strcmp(var, "rebase.autosquash")) {
1206                opts->autosquash = git_config_bool(var, value);
1207                return 0;
1208        }
1209
1210        if (!strcmp(var, "commit.gpgsign")) {
1211                free(opts->gpg_sign_opt);
1212                opts->gpg_sign_opt = git_config_bool(var, value) ?
1213                        xstrdup("-S") : NULL;
1214                return 0;
1215        }
1216
1217        if (!strcmp(var, "rebase.autostash")) {
1218                opts->autostash = git_config_bool(var, value);
1219                return 0;
1220        }
1221
1222        if (!strcmp(var, "rebase.reschedulefailedexec")) {
1223                opts->reschedule_failed_exec = git_config_bool(var, value);
1224                return 0;
1225        }
1226
1227        if (!strcmp(var, "rebase.usebuiltin")) {
1228                opts->use_legacy_rebase = !git_config_bool(var, value);
1229                return 0;
1230        }
1231
1232        return git_default_config(var, value, data);
1233}
1234
1235/*
1236 * Determines whether the commits in from..to are linear, i.e. contain
1237 * no merge commits. This function *expects* `from` to be an ancestor of
1238 * `to`.
1239 */
1240static int is_linear_history(struct commit *from, struct commit *to)
1241{
1242        while (to && to != from) {
1243                parse_commit(to);
1244                if (!to->parents)
1245                        return 1;
1246                if (to->parents->next)
1247                        return 0;
1248                to = to->parents->item;
1249        }
1250        return 1;
1251}
1252
1253static int can_fast_forward(struct commit *onto, struct object_id *head_oid,
1254                            struct object_id *merge_base)
1255{
1256        struct commit *head = lookup_commit(the_repository, head_oid);
1257        struct commit_list *merge_bases;
1258        int res;
1259
1260        if (!head)
1261                return 0;
1262
1263        merge_bases = get_merge_bases(onto, head);
1264        if (merge_bases && !merge_bases->next) {
1265                oidcpy(merge_base, &merge_bases->item->object.oid);
1266                res = oideq(merge_base, &onto->object.oid);
1267        } else {
1268                oidcpy(merge_base, &null_oid);
1269                res = 0;
1270        }
1271        free_commit_list(merge_bases);
1272        return res && is_linear_history(onto, head);
1273}
1274
1275/* -i followed by -m is still -i */
1276static int parse_opt_merge(const struct option *opt, const char *arg, int unset)
1277{
1278        struct rebase_options *opts = opt->value;
1279
1280        BUG_ON_OPT_NEG(unset);
1281        BUG_ON_OPT_ARG(arg);
1282
1283        if (!is_interactive(opts))
1284                opts->type = REBASE_MERGE;
1285
1286        return 0;
1287}
1288
1289/* -i followed by -p is still explicitly interactive, but -p alone is not */
1290static int parse_opt_interactive(const struct option *opt, const char *arg,
1291                                 int unset)
1292{
1293        struct rebase_options *opts = opt->value;
1294
1295        BUG_ON_OPT_NEG(unset);
1296        BUG_ON_OPT_ARG(arg);
1297
1298        opts->type = REBASE_INTERACTIVE;
1299        opts->flags |= REBASE_INTERACTIVE_EXPLICIT;
1300
1301        return 0;
1302}
1303
1304static void NORETURN error_on_missing_default_upstream(void)
1305{
1306        struct branch *current_branch = branch_get(NULL);
1307
1308        printf(_("%s\n"
1309                 "Please specify which branch you want to rebase against.\n"
1310                 "See git-rebase(1) for details.\n"
1311                 "\n"
1312                 "    git rebase '<branch>'\n"
1313                 "\n"),
1314                current_branch ? _("There is no tracking information for "
1315                        "the current branch.") :
1316                        _("You are not currently on a branch."));
1317
1318        if (current_branch) {
1319                const char *remote = current_branch->remote_name;
1320
1321                if (!remote)
1322                        remote = _("<remote>");
1323
1324                printf(_("If you wish to set tracking information for this "
1325                         "branch you can do so with:\n"
1326                         "\n"
1327                         "    git branch --set-upstream-to=%s/<branch> %s\n"
1328                         "\n"),
1329                       remote, current_branch->name);
1330        }
1331        exit(1);
1332}
1333
1334static void set_reflog_action(struct rebase_options *options)
1335{
1336        const char *env;
1337        struct strbuf buf = STRBUF_INIT;
1338
1339        if (!is_interactive(options))
1340                return;
1341
1342        env = getenv(GIT_REFLOG_ACTION_ENVIRONMENT);
1343        if (env && strcmp("rebase", env))
1344                return; /* only override it if it is "rebase" */
1345
1346        strbuf_addf(&buf, "rebase -i (%s)", options->action);
1347        setenv(GIT_REFLOG_ACTION_ENVIRONMENT, buf.buf, 1);
1348        strbuf_release(&buf);
1349}
1350
1351static int check_exec_cmd(const char *cmd)
1352{
1353        if (strchr(cmd, '\n'))
1354                return error(_("exec commands cannot contain newlines"));
1355
1356        /* Does the command consist purely of whitespace? */
1357        if (!cmd[strspn(cmd, " \t\r\f\v")])
1358                return error(_("empty exec command"));
1359
1360        return 0;
1361}
1362
1363
1364int cmd_rebase(int argc, const char **argv, const char *prefix)
1365{
1366        struct rebase_options options = REBASE_OPTIONS_INIT;
1367        const char *branch_name;
1368        int ret, flags, total_argc, in_progress = 0;
1369        int ok_to_skip_pre_rebase = 0;
1370        struct strbuf msg = STRBUF_INIT;
1371        struct strbuf revisions = STRBUF_INIT;
1372        struct strbuf buf = STRBUF_INIT;
1373        struct object_id merge_base;
1374        enum action action = ACTION_NONE;
1375        const char *gpg_sign = NULL;
1376        struct string_list exec = STRING_LIST_INIT_NODUP;
1377        const char *rebase_merges = NULL;
1378        int fork_point = -1;
1379        struct string_list strategy_options = STRING_LIST_INIT_NODUP;
1380        struct object_id squash_onto;
1381        char *squash_onto_name = NULL;
1382        struct option builtin_rebase_options[] = {
1383                OPT_STRING(0, "onto", &options.onto_name,
1384                           N_("revision"),
1385                           N_("rebase onto given branch instead of upstream")),
1386                OPT_BOOL(0, "no-verify", &ok_to_skip_pre_rebase,
1387                         N_("allow pre-rebase hook to run")),
1388                OPT_NEGBIT('q', "quiet", &options.flags,
1389                           N_("be quiet. implies --no-stat"),
1390                           REBASE_NO_QUIET| REBASE_VERBOSE | REBASE_DIFFSTAT),
1391                OPT_BIT('v', "verbose", &options.flags,
1392                        N_("display a diffstat of what changed upstream"),
1393                        REBASE_NO_QUIET | REBASE_VERBOSE | REBASE_DIFFSTAT),
1394                {OPTION_NEGBIT, 'n', "no-stat", &options.flags, NULL,
1395                        N_("do not show diffstat of what changed upstream"),
1396                        PARSE_OPT_NOARG, NULL, REBASE_DIFFSTAT },
1397                OPT_BOOL(0, "signoff", &options.signoff,
1398                         N_("add a Signed-off-by: line to each commit")),
1399                OPT_PASSTHRU_ARGV(0, "ignore-whitespace", &options.git_am_opts,
1400                                  NULL, N_("passed to 'git am'"),
1401                                  PARSE_OPT_NOARG),
1402                OPT_PASSTHRU_ARGV(0, "committer-date-is-author-date",
1403                                  &options.git_am_opts, NULL,
1404                                  N_("passed to 'git am'"), PARSE_OPT_NOARG),
1405                OPT_PASSTHRU_ARGV(0, "ignore-date", &options.git_am_opts, NULL,
1406                                  N_("passed to 'git am'"), PARSE_OPT_NOARG),
1407                OPT_PASSTHRU_ARGV('C', NULL, &options.git_am_opts, N_("n"),
1408                                  N_("passed to 'git apply'"), 0),
1409                OPT_PASSTHRU_ARGV(0, "whitespace", &options.git_am_opts,
1410                                  N_("action"), N_("passed to 'git apply'"), 0),
1411                OPT_BIT('f', "force-rebase", &options.flags,
1412                        N_("cherry-pick all commits, even if unchanged"),
1413                        REBASE_FORCE),
1414                OPT_BIT(0, "no-ff", &options.flags,
1415                        N_("cherry-pick all commits, even if unchanged"),
1416                        REBASE_FORCE),
1417                OPT_CMDMODE(0, "continue", &action, N_("continue"),
1418                            ACTION_CONTINUE),
1419                OPT_CMDMODE(0, "skip", &action,
1420                            N_("skip current patch and continue"), ACTION_SKIP),
1421                OPT_CMDMODE(0, "abort", &action,
1422                            N_("abort and check out the original branch"),
1423                            ACTION_ABORT),
1424                OPT_CMDMODE(0, "quit", &action,
1425                            N_("abort but keep HEAD where it is"), ACTION_QUIT),
1426                OPT_CMDMODE(0, "edit-todo", &action, N_("edit the todo list "
1427                            "during an interactive rebase"), ACTION_EDIT_TODO),
1428                OPT_CMDMODE(0, "show-current-patch", &action,
1429                            N_("show the patch file being applied or merged"),
1430                            ACTION_SHOW_CURRENT_PATCH),
1431                { OPTION_CALLBACK, 'm', "merge", &options, NULL,
1432                        N_("use merging strategies to rebase"),
1433                        PARSE_OPT_NOARG | PARSE_OPT_NONEG,
1434                        parse_opt_merge },
1435                { OPTION_CALLBACK, 'i', "interactive", &options, NULL,
1436                        N_("let the user edit the list of commits to rebase"),
1437                        PARSE_OPT_NOARG | PARSE_OPT_NONEG,
1438                        parse_opt_interactive },
1439                OPT_SET_INT('p', "preserve-merges", &options.type,
1440                            N_("(DEPRECATED) try to recreate merges instead of "
1441                               "ignoring them"), REBASE_PRESERVE_MERGES),
1442                OPT_RERERE_AUTOUPDATE(&options.allow_rerere_autoupdate),
1443                OPT_BOOL('k', "keep-empty", &options.keep_empty,
1444                         N_("preserve empty commits during rebase")),
1445                OPT_BOOL(0, "autosquash", &options.autosquash,
1446                         N_("move commits that begin with "
1447                            "squash!/fixup! under -i")),
1448                { OPTION_STRING, 'S', "gpg-sign", &gpg_sign, N_("key-id"),
1449                        N_("GPG-sign commits"),
1450                        PARSE_OPT_OPTARG, NULL, (intptr_t) "" },
1451                OPT_BOOL(0, "autostash", &options.autostash,
1452                         N_("automatically stash/stash pop before and after")),
1453                OPT_STRING_LIST('x', "exec", &exec, N_("exec"),
1454                                N_("add exec lines after each commit of the "
1455                                   "editable list")),
1456                OPT_BOOL(0, "allow-empty-message",
1457                         &options.allow_empty_message,
1458                         N_("allow rebasing commits with empty messages")),
1459                {OPTION_STRING, 'r', "rebase-merges", &rebase_merges,
1460                        N_("mode"),
1461                        N_("try to rebase merges instead of skipping them"),
1462                        PARSE_OPT_OPTARG, NULL, (intptr_t)""},
1463                OPT_BOOL(0, "fork-point", &fork_point,
1464                         N_("use 'merge-base --fork-point' to refine upstream")),
1465                OPT_STRING('s', "strategy", &options.strategy,
1466                           N_("strategy"), N_("use the given merge strategy")),
1467                OPT_STRING_LIST('X', "strategy-option", &strategy_options,
1468                                N_("option"),
1469                                N_("pass the argument through to the merge "
1470                                   "strategy")),
1471                OPT_BOOL(0, "root", &options.root,
1472                         N_("rebase all reachable commits up to the root(s)")),
1473                OPT_BOOL(0, "reschedule-failed-exec",
1474                         &options.reschedule_failed_exec,
1475                         N_("automatically re-schedule any `exec` that fails")),
1476                OPT_END(),
1477        };
1478        int i;
1479
1480        if (argc == 2 && !strcmp(argv[1], "-h"))
1481                usage_with_options(builtin_rebase_usage,
1482                                   builtin_rebase_options);
1483
1484        prefix = setup_git_directory();
1485        trace_repo_setup(prefix);
1486        setup_work_tree();
1487
1488        options.allow_empty_message = 1;
1489        git_config(rebase_config, &options);
1490
1491        if (options.use_legacy_rebase ||
1492            !git_env_bool("GIT_TEST_REBASE_USE_BUILTIN", -1))
1493                warning(_("the rebase.useBuiltin support has been removed!\n"
1494                          "See its entry in 'git help config' for details."));
1495
1496        strbuf_reset(&buf);
1497        strbuf_addf(&buf, "%s/applying", apply_dir());
1498        if(file_exists(buf.buf))
1499                die(_("It looks like 'git am' is in progress. Cannot rebase."));
1500
1501        if (is_directory(apply_dir())) {
1502                options.type = REBASE_AM;
1503                options.state_dir = apply_dir();
1504        } else if (is_directory(merge_dir())) {
1505                strbuf_reset(&buf);
1506                strbuf_addf(&buf, "%s/rewritten", merge_dir());
1507                if (is_directory(buf.buf)) {
1508                        options.type = REBASE_PRESERVE_MERGES;
1509                        options.flags |= REBASE_INTERACTIVE_EXPLICIT;
1510                } else {
1511                        strbuf_reset(&buf);
1512                        strbuf_addf(&buf, "%s/interactive", merge_dir());
1513                        if(file_exists(buf.buf)) {
1514                                options.type = REBASE_INTERACTIVE;
1515                                options.flags |= REBASE_INTERACTIVE_EXPLICIT;
1516                        } else
1517                                options.type = REBASE_MERGE;
1518                }
1519                options.state_dir = merge_dir();
1520        }
1521
1522        if (options.type != REBASE_UNSPECIFIED)
1523                in_progress = 1;
1524
1525        total_argc = argc;
1526        argc = parse_options(argc, argv, prefix,
1527                             builtin_rebase_options,
1528                             builtin_rebase_usage, 0);
1529
1530        if (action != ACTION_NONE && total_argc != 2) {
1531                usage_with_options(builtin_rebase_usage,
1532                                   builtin_rebase_options);
1533        }
1534
1535        if (argc > 2)
1536                usage_with_options(builtin_rebase_usage,
1537                                   builtin_rebase_options);
1538
1539        if (options.type == REBASE_PRESERVE_MERGES)
1540                warning(_("git rebase --preserve-merges is deprecated. "
1541                          "Use --rebase-merges instead."));
1542
1543        if (action != ACTION_NONE && !in_progress)
1544                die(_("No rebase in progress?"));
1545        setenv(GIT_REFLOG_ACTION_ENVIRONMENT, "rebase", 0);
1546
1547        if (action == ACTION_EDIT_TODO && !is_interactive(&options))
1548                die(_("The --edit-todo action can only be used during "
1549                      "interactive rebase."));
1550
1551        if (trace2_is_enabled()) {
1552                if (is_interactive(&options))
1553                        trace2_cmd_mode("interactive");
1554                else if (exec.nr)
1555                        trace2_cmd_mode("interactive-exec");
1556                else
1557                        trace2_cmd_mode(action_names[action]);
1558        }
1559
1560        switch (action) {
1561        case ACTION_CONTINUE: {
1562                struct object_id head;
1563                struct lock_file lock_file = LOCK_INIT;
1564                int fd;
1565
1566                options.action = "continue";
1567                set_reflog_action(&options);
1568
1569                /* Sanity check */
1570                if (get_oid("HEAD", &head))
1571                        die(_("Cannot read HEAD"));
1572
1573                fd = hold_locked_index(&lock_file, 0);
1574                if (repo_read_index(the_repository) < 0)
1575                        die(_("could not read index"));
1576                refresh_index(the_repository->index, REFRESH_QUIET, NULL, NULL,
1577                              NULL);
1578                if (0 <= fd)
1579                        repo_update_index_if_able(the_repository, &lock_file);
1580                rollback_lock_file(&lock_file);
1581
1582                if (has_unstaged_changes(the_repository, 1)) {
1583                        puts(_("You must edit all merge conflicts and then\n"
1584                               "mark them as resolved using git add"));
1585                        exit(1);
1586                }
1587                if (read_basic_state(&options))
1588                        exit(1);
1589                goto run_rebase;
1590        }
1591        case ACTION_SKIP: {
1592                struct string_list merge_rr = STRING_LIST_INIT_DUP;
1593
1594                options.action = "skip";
1595                set_reflog_action(&options);
1596
1597                rerere_clear(the_repository, &merge_rr);
1598                string_list_clear(&merge_rr, 1);
1599
1600                if (reset_head(NULL, "reset", NULL, RESET_HEAD_HARD,
1601                               NULL, NULL) < 0)
1602                        die(_("could not discard worktree changes"));
1603                remove_branch_state(the_repository);
1604                if (read_basic_state(&options))
1605                        exit(1);
1606                goto run_rebase;
1607        }
1608        case ACTION_ABORT: {
1609                struct string_list merge_rr = STRING_LIST_INIT_DUP;
1610                options.action = "abort";
1611                set_reflog_action(&options);
1612
1613                rerere_clear(the_repository, &merge_rr);
1614                string_list_clear(&merge_rr, 1);
1615
1616                if (read_basic_state(&options))
1617                        exit(1);
1618                if (reset_head(&options.orig_head, "reset",
1619                               options.head_name, RESET_HEAD_HARD,
1620                               NULL, NULL) < 0)
1621                        die(_("could not move back to %s"),
1622                            oid_to_hex(&options.orig_head));
1623                remove_branch_state(the_repository);
1624                ret = finish_rebase(&options);
1625                goto cleanup;
1626        }
1627        case ACTION_QUIT: {
1628                strbuf_reset(&buf);
1629                strbuf_addstr(&buf, options.state_dir);
1630                ret = !!remove_dir_recursively(&buf, 0);
1631                if (ret)
1632                        die(_("could not remove '%s'"), options.state_dir);
1633                goto cleanup;
1634        }
1635        case ACTION_EDIT_TODO:
1636                options.action = "edit-todo";
1637                options.dont_finish_rebase = 1;
1638                goto run_rebase;
1639        case ACTION_SHOW_CURRENT_PATCH:
1640                options.action = "show-current-patch";
1641                options.dont_finish_rebase = 1;
1642                goto run_rebase;
1643        case ACTION_NONE:
1644                break;
1645        default:
1646                BUG("action: %d", action);
1647        }
1648
1649        /* Make sure no rebase is in progress */
1650        if (in_progress) {
1651                const char *last_slash = strrchr(options.state_dir, '/');
1652                const char *state_dir_base =
1653                        last_slash ? last_slash + 1 : options.state_dir;
1654                const char *cmd_live_rebase =
1655                        "git rebase (--continue | --abort | --skip)";
1656                strbuf_reset(&buf);
1657                strbuf_addf(&buf, "rm -fr \"%s\"", options.state_dir);
1658                die(_("It seems that there is already a %s directory, and\n"
1659                      "I wonder if you are in the middle of another rebase.  "
1660                      "If that is the\n"
1661                      "case, please try\n\t%s\n"
1662                      "If that is not the case, please\n\t%s\n"
1663                      "and run me again.  I am stopping in case you still "
1664                      "have something\n"
1665                      "valuable there.\n"),
1666                    state_dir_base, cmd_live_rebase, buf.buf);
1667        }
1668
1669        for (i = 0; i < options.git_am_opts.argc; i++) {
1670                const char *option = options.git_am_opts.argv[i], *p;
1671                if (!strcmp(option, "--committer-date-is-author-date") ||
1672                    !strcmp(option, "--ignore-date") ||
1673                    !strcmp(option, "--whitespace=fix") ||
1674                    !strcmp(option, "--whitespace=strip"))
1675                        options.flags |= REBASE_FORCE;
1676                else if (skip_prefix(option, "-C", &p)) {
1677                        while (*p)
1678                                if (!isdigit(*(p++)))
1679                                        die(_("switch `C' expects a "
1680                                              "numerical value"));
1681                } else if (skip_prefix(option, "--whitespace=", &p)) {
1682                        if (*p && strcmp(p, "warn") && strcmp(p, "nowarn") &&
1683                            strcmp(p, "error") && strcmp(p, "error-all"))
1684                                die("Invalid whitespace option: '%s'", p);
1685                }
1686        }
1687
1688        for (i = 0; i < exec.nr; i++)
1689                if (check_exec_cmd(exec.items[i].string))
1690                        exit(1);
1691
1692        if (!(options.flags & REBASE_NO_QUIET))
1693                argv_array_push(&options.git_am_opts, "-q");
1694
1695        if (options.keep_empty)
1696                imply_interactive(&options, "--keep-empty");
1697
1698        if (gpg_sign) {
1699                free(options.gpg_sign_opt);
1700                options.gpg_sign_opt = xstrfmt("-S%s", gpg_sign);
1701        }
1702
1703        if (exec.nr) {
1704                int i;
1705
1706                imply_interactive(&options, "--exec");
1707
1708                strbuf_reset(&buf);
1709                for (i = 0; i < exec.nr; i++)
1710                        strbuf_addf(&buf, "exec %s\n", exec.items[i].string);
1711                options.cmd = xstrdup(buf.buf);
1712        }
1713
1714        if (rebase_merges) {
1715                if (!*rebase_merges)
1716                        ; /* default mode; do nothing */
1717                else if (!strcmp("rebase-cousins", rebase_merges))
1718                        options.rebase_cousins = 1;
1719                else if (strcmp("no-rebase-cousins", rebase_merges))
1720                        die(_("Unknown mode: %s"), rebase_merges);
1721                options.rebase_merges = 1;
1722                imply_interactive(&options, "--rebase-merges");
1723        }
1724
1725        if (strategy_options.nr) {
1726                int i;
1727
1728                if (!options.strategy)
1729                        options.strategy = "recursive";
1730
1731                strbuf_reset(&buf);
1732                for (i = 0; i < strategy_options.nr; i++)
1733                        strbuf_addf(&buf, " --%s",
1734                                    strategy_options.items[i].string);
1735                options.strategy_opts = xstrdup(buf.buf);
1736        }
1737
1738        if (options.strategy) {
1739                options.strategy = xstrdup(options.strategy);
1740                switch (options.type) {
1741                case REBASE_AM:
1742                        die(_("--strategy requires --merge or --interactive"));
1743                case REBASE_MERGE:
1744                case REBASE_INTERACTIVE:
1745                case REBASE_PRESERVE_MERGES:
1746                        /* compatible */
1747                        break;
1748                case REBASE_UNSPECIFIED:
1749                        options.type = REBASE_MERGE;
1750                        break;
1751                default:
1752                        BUG("unhandled rebase type (%d)", options.type);
1753                }
1754        }
1755
1756        if (options.type == REBASE_MERGE)
1757                imply_interactive(&options, "--merge");
1758
1759        if (options.root && !options.onto_name)
1760                imply_interactive(&options, "--root without --onto");
1761
1762        if (isatty(2) && options.flags & REBASE_NO_QUIET)
1763                strbuf_addstr(&options.git_format_patch_opt, " --progress");
1764
1765        switch (options.type) {
1766        case REBASE_MERGE:
1767        case REBASE_INTERACTIVE:
1768        case REBASE_PRESERVE_MERGES:
1769                options.state_dir = merge_dir();
1770                break;
1771        case REBASE_AM:
1772                options.state_dir = apply_dir();
1773                break;
1774        default:
1775                /* the default rebase backend is `--am` */
1776                options.type = REBASE_AM;
1777                options.state_dir = apply_dir();
1778                break;
1779        }
1780
1781        if (options.reschedule_failed_exec && !is_interactive(&options))
1782                die(_("%s requires an interactive rebase"), "--reschedule-failed-exec");
1783
1784        if (options.git_am_opts.argc) {
1785                /* all am options except -q are compatible only with --am */
1786                for (i = options.git_am_opts.argc - 1; i >= 0; i--)
1787                        if (strcmp(options.git_am_opts.argv[i], "-q"))
1788                                break;
1789
1790                if (is_interactive(&options) && i >= 0)
1791                        die(_("cannot combine am options with either "
1792                              "interactive or merge options"));
1793        }
1794
1795        if (options.signoff) {
1796                if (options.type == REBASE_PRESERVE_MERGES)
1797                        die("cannot combine '--signoff' with "
1798                            "'--preserve-merges'");
1799                argv_array_push(&options.git_am_opts, "--signoff");
1800                options.flags |= REBASE_FORCE;
1801        }
1802
1803        if (options.type == REBASE_PRESERVE_MERGES) {
1804                /*
1805                 * Note: incompatibility with --signoff handled in signoff block above
1806                 * Note: incompatibility with --interactive is just a strong warning;
1807                 *       git-rebase.txt caveats with "unless you know what you are doing"
1808                 */
1809                if (options.rebase_merges)
1810                        die(_("cannot combine '--preserve-merges' with "
1811                              "'--rebase-merges'"));
1812
1813                if (options.reschedule_failed_exec)
1814                        die(_("error: cannot combine '--preserve-merges' with "
1815                              "'--reschedule-failed-exec'"));
1816        }
1817
1818        if (options.rebase_merges) {
1819                if (strategy_options.nr)
1820                        die(_("cannot combine '--rebase-merges' with "
1821                              "'--strategy-option'"));
1822                if (options.strategy)
1823                        die(_("cannot combine '--rebase-merges' with "
1824                              "'--strategy'"));
1825        }
1826
1827        if (!options.root) {
1828                if (argc < 1) {
1829                        struct branch *branch;
1830
1831                        branch = branch_get(NULL);
1832                        options.upstream_name = branch_get_upstream(branch,
1833                                                                    NULL);
1834                        if (!options.upstream_name)
1835                                error_on_missing_default_upstream();
1836                        if (fork_point < 0)
1837                                fork_point = 1;
1838                } else {
1839                        options.upstream_name = argv[0];
1840                        argc--;
1841                        argv++;
1842                        if (!strcmp(options.upstream_name, "-"))
1843                                options.upstream_name = "@{-1}";
1844                }
1845                options.upstream = peel_committish(options.upstream_name);
1846                if (!options.upstream)
1847                        die(_("invalid upstream '%s'"), options.upstream_name);
1848                options.upstream_arg = options.upstream_name;
1849        } else {
1850                if (!options.onto_name) {
1851                        if (commit_tree("", 0, the_hash_algo->empty_tree, NULL,
1852                                        &squash_onto, NULL, NULL) < 0)
1853                                die(_("Could not create new root commit"));
1854                        options.squash_onto = &squash_onto;
1855                        options.onto_name = squash_onto_name =
1856                                xstrdup(oid_to_hex(&squash_onto));
1857                }
1858                options.upstream_name = NULL;
1859                options.upstream = NULL;
1860                if (argc > 1)
1861                        usage_with_options(builtin_rebase_usage,
1862                                           builtin_rebase_options);
1863                options.upstream_arg = "--root";
1864        }
1865
1866        /* Make sure the branch to rebase onto is valid. */
1867        if (!options.onto_name)
1868                options.onto_name = options.upstream_name;
1869        if (strstr(options.onto_name, "...")) {
1870                if (get_oid_mb(options.onto_name, &merge_base) < 0)
1871                        die(_("'%s': need exactly one merge base"),
1872                            options.onto_name);
1873                options.onto = lookup_commit_or_die(&merge_base,
1874                                                    options.onto_name);
1875        } else {
1876                options.onto = peel_committish(options.onto_name);
1877                if (!options.onto)
1878                        die(_("Does not point to a valid commit '%s'"),
1879                                options.onto_name);
1880        }
1881
1882        /*
1883         * If the branch to rebase is given, that is the branch we will rebase
1884         * branch_name -- branch/commit being rebased, or
1885         *                HEAD (already detached)
1886         * orig_head -- commit object name of tip of the branch before rebasing
1887         * head_name -- refs/heads/<that-branch> or NULL (detached HEAD)
1888         */
1889        if (argc == 1) {
1890                /* Is it "rebase other branchname" or "rebase other commit"? */
1891                branch_name = argv[0];
1892                options.switch_to = argv[0];
1893
1894                /* Is it a local branch? */
1895                strbuf_reset(&buf);
1896                strbuf_addf(&buf, "refs/heads/%s", branch_name);
1897                if (!read_ref(buf.buf, &options.orig_head))
1898                        options.head_name = xstrdup(buf.buf);
1899                /* If not is it a valid ref (branch or commit)? */
1900                else if (!get_oid(branch_name, &options.orig_head))
1901                        options.head_name = NULL;
1902                else
1903                        die(_("fatal: no such branch/commit '%s'"),
1904                            branch_name);
1905        } else if (argc == 0) {
1906                /* Do not need to switch branches, we are already on it. */
1907                options.head_name =
1908                        xstrdup_or_null(resolve_ref_unsafe("HEAD", 0, NULL,
1909                                         &flags));
1910                if (!options.head_name)
1911                        die(_("No such ref: %s"), "HEAD");
1912                if (flags & REF_ISSYMREF) {
1913                        if (!skip_prefix(options.head_name,
1914                                         "refs/heads/", &branch_name))
1915                                branch_name = options.head_name;
1916
1917                } else {
1918                        FREE_AND_NULL(options.head_name);
1919                        branch_name = "HEAD";
1920                }
1921                if (get_oid("HEAD", &options.orig_head))
1922                        die(_("Could not resolve HEAD to a revision"));
1923        } else
1924                BUG("unexpected number of arguments left to parse");
1925
1926        if (fork_point > 0) {
1927                struct commit *head =
1928                        lookup_commit_reference(the_repository,
1929                                                &options.orig_head);
1930                options.restrict_revision =
1931                        get_fork_point(options.upstream_name, head);
1932        }
1933
1934        if (repo_read_index(the_repository) < 0)
1935                die(_("could not read index"));
1936
1937        if (options.autostash) {
1938                struct lock_file lock_file = LOCK_INIT;
1939                int fd;
1940
1941                fd = hold_locked_index(&lock_file, 0);
1942                refresh_cache(REFRESH_QUIET);
1943                if (0 <= fd)
1944                        repo_update_index_if_able(the_repository, &lock_file);
1945                rollback_lock_file(&lock_file);
1946
1947                if (has_unstaged_changes(the_repository, 1) ||
1948                    has_uncommitted_changes(the_repository, 1)) {
1949                        const char *autostash =
1950                                state_dir_path("autostash", &options);
1951                        struct child_process stash = CHILD_PROCESS_INIT;
1952                        struct object_id oid;
1953                        struct commit *head =
1954                                lookup_commit_reference(the_repository,
1955                                                        &options.orig_head);
1956
1957                        argv_array_pushl(&stash.args,
1958                                         "stash", "create", "autostash", NULL);
1959                        stash.git_cmd = 1;
1960                        stash.no_stdin = 1;
1961                        strbuf_reset(&buf);
1962                        if (capture_command(&stash, &buf, GIT_MAX_HEXSZ))
1963                                die(_("Cannot autostash"));
1964                        strbuf_trim_trailing_newline(&buf);
1965                        if (get_oid(buf.buf, &oid))
1966                                die(_("Unexpected stash response: '%s'"),
1967                                    buf.buf);
1968                        strbuf_reset(&buf);
1969                        strbuf_add_unique_abbrev(&buf, &oid, DEFAULT_ABBREV);
1970
1971                        if (safe_create_leading_directories_const(autostash))
1972                                die(_("Could not create directory for '%s'"),
1973                                    options.state_dir);
1974                        write_file(autostash, "%s", oid_to_hex(&oid));
1975                        printf(_("Created autostash: %s\n"), buf.buf);
1976                        if (reset_head(&head->object.oid, "reset --hard",
1977                                       NULL, RESET_HEAD_HARD, NULL, NULL) < 0)
1978                                die(_("could not reset --hard"));
1979                        printf(_("HEAD is now at %s"),
1980                               find_unique_abbrev(&head->object.oid,
1981                                                  DEFAULT_ABBREV));
1982                        strbuf_reset(&buf);
1983                        pp_commit_easy(CMIT_FMT_ONELINE, head, &buf);
1984                        if (buf.len > 0)
1985                                printf(" %s", buf.buf);
1986                        putchar('\n');
1987
1988                        if (discard_index(the_repository->index) < 0 ||
1989                                repo_read_index(the_repository) < 0)
1990                                die(_("could not read index"));
1991                }
1992        }
1993
1994        if (require_clean_work_tree(the_repository, "rebase",
1995                                    _("Please commit or stash them."), 1, 1)) {
1996                ret = 1;
1997                goto cleanup;
1998        }
1999
2000        /*
2001         * Now we are rebasing commits upstream..orig_head (or with --root,
2002         * everything leading up to orig_head) on top of onto.
2003         */
2004
2005        /*
2006         * Check if we are already based on onto with linear history,
2007         * but this should be done only when upstream and onto are the same
2008         * and if this is not an interactive rebase.
2009         */
2010        if (can_fast_forward(options.onto, &options.orig_head, &merge_base) &&
2011            !is_interactive(&options) && !options.restrict_revision &&
2012            options.upstream &&
2013            !oidcmp(&options.upstream->object.oid, &options.onto->object.oid)) {
2014                int flag;
2015
2016                if (!(options.flags & REBASE_FORCE)) {
2017                        /* Lazily switch to the target branch if needed... */
2018                        if (options.switch_to) {
2019                                struct object_id oid;
2020
2021                                if (get_oid(options.switch_to, &oid) < 0) {
2022                                        ret = !!error(_("could not parse '%s'"),
2023                                                      options.switch_to);
2024                                        goto cleanup;
2025                                }
2026
2027                                strbuf_reset(&buf);
2028                                strbuf_addf(&buf, "%s: checkout %s",
2029                                            getenv(GIT_REFLOG_ACTION_ENVIRONMENT),
2030                                            options.switch_to);
2031                                if (reset_head(&oid, "checkout",
2032                                               options.head_name,
2033                                               RESET_HEAD_RUN_POST_CHECKOUT_HOOK,
2034                                               NULL, buf.buf) < 0) {
2035                                        ret = !!error(_("could not switch to "
2036                                                        "%s"),
2037                                                      options.switch_to);
2038                                        goto cleanup;
2039                                }
2040                        }
2041
2042                        if (!(options.flags & REBASE_NO_QUIET))
2043                                ; /* be quiet */
2044                        else if (!strcmp(branch_name, "HEAD") &&
2045                                 resolve_ref_unsafe("HEAD", 0, NULL, &flag))
2046                                puts(_("HEAD is up to date."));
2047                        else
2048                                printf(_("Current branch %s is up to date.\n"),
2049                                       branch_name);
2050                        ret = !!finish_rebase(&options);
2051                        goto cleanup;
2052                } else if (!(options.flags & REBASE_NO_QUIET))
2053                        ; /* be quiet */
2054                else if (!strcmp(branch_name, "HEAD") &&
2055                         resolve_ref_unsafe("HEAD", 0, NULL, &flag))
2056                        puts(_("HEAD is up to date, rebase forced."));
2057                else
2058                        printf(_("Current branch %s is up to date, rebase "
2059                                 "forced.\n"), branch_name);
2060        }
2061
2062        /* If a hook exists, give it a chance to interrupt*/
2063        if (!ok_to_skip_pre_rebase &&
2064            run_hook_le(NULL, "pre-rebase", options.upstream_arg,
2065                        argc ? argv[0] : NULL, NULL))
2066                die(_("The pre-rebase hook refused to rebase."));
2067
2068        if (options.flags & REBASE_DIFFSTAT) {
2069                struct diff_options opts;
2070
2071                if (options.flags & REBASE_VERBOSE) {
2072                        if (is_null_oid(&merge_base))
2073                                printf(_("Changes to %s:\n"),
2074                                       oid_to_hex(&options.onto->object.oid));
2075                        else
2076                                printf(_("Changes from %s to %s:\n"),
2077                                       oid_to_hex(&merge_base),
2078                                       oid_to_hex(&options.onto->object.oid));
2079                }
2080
2081                /* We want color (if set), but no pager */
2082                diff_setup(&opts);
2083                opts.stat_width = -1; /* use full terminal width */
2084                opts.stat_graph_width = -1; /* respect statGraphWidth config */
2085                opts.output_format |=
2086                        DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
2087                opts.detect_rename = DIFF_DETECT_RENAME;
2088                diff_setup_done(&opts);
2089                diff_tree_oid(is_null_oid(&merge_base) ?
2090                              the_hash_algo->empty_tree : &merge_base,
2091                              &options.onto->object.oid, "", &opts);
2092                diffcore_std(&opts);
2093                diff_flush(&opts);
2094        }
2095
2096        if (is_interactive(&options))
2097                goto run_rebase;
2098
2099        /* Detach HEAD and reset the tree */
2100        if (options.flags & REBASE_NO_QUIET)
2101                printf(_("First, rewinding head to replay your work on top of "
2102                         "it...\n"));
2103
2104        strbuf_addf(&msg, "%s: checkout %s",
2105                    getenv(GIT_REFLOG_ACTION_ENVIRONMENT), options.onto_name);
2106        if (reset_head(&options.onto->object.oid, "checkout", NULL,
2107                       RESET_HEAD_DETACH | RESET_ORIG_HEAD | 
2108                       RESET_HEAD_RUN_POST_CHECKOUT_HOOK,
2109                       NULL, msg.buf))
2110                die(_("Could not detach HEAD"));
2111        strbuf_release(&msg);
2112
2113        /*
2114         * If the onto is a proper descendant of the tip of the branch, then
2115         * we just fast-forwarded.
2116         */
2117        strbuf_reset(&msg);
2118        if (oideq(&merge_base, &options.orig_head)) {
2119                printf(_("Fast-forwarded %s to %s.\n"),
2120                        branch_name, options.onto_name);
2121                strbuf_addf(&msg, "rebase finished: %s onto %s",
2122                        options.head_name ? options.head_name : "detached HEAD",
2123                        oid_to_hex(&options.onto->object.oid));
2124                reset_head(NULL, "Fast-forwarded", options.head_name,
2125                           RESET_HEAD_REFS_ONLY, "HEAD", msg.buf);
2126                strbuf_release(&msg);
2127                ret = !!finish_rebase(&options);
2128                goto cleanup;
2129        }
2130
2131        strbuf_addf(&revisions, "%s..%s",
2132                    options.root ? oid_to_hex(&options.onto->object.oid) :
2133                    (options.restrict_revision ?
2134                     oid_to_hex(&options.restrict_revision->object.oid) :
2135                     oid_to_hex(&options.upstream->object.oid)),
2136                    oid_to_hex(&options.orig_head));
2137
2138        options.revisions = revisions.buf;
2139
2140run_rebase:
2141        ret = !!run_specific_rebase(&options, action);
2142
2143cleanup:
2144        strbuf_release(&revisions);
2145        free(options.head_name);
2146        free(options.gpg_sign_opt);
2147        free(options.cmd);
2148        free(squash_onto_name);
2149        return ret;
2150}