builtin/rebase.c

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