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

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