git.oblomov.eu Git - git/blob - sequencer.c

   1 #include "cache.h"
   2 #include "lockfile.h"
   3 #include "sequencer.h"
   4 #include "dir.h"
   5 #include "object.h"
   6 #include "commit.h"
   7 #include "tag.h"
   8 #include "run-command.h"
   9 #include "exec_cmd.h"
  10 #include "utf8.h"
  11 #include "cache-tree.h"
  12 #include "diff.h"
  13 #include "revision.h"
  14 #include "rerere.h"
  15 #include "merge-recursive.h"
  16 #include "refs.h"
  17 #include "argv-array.h"
  18 #include "rewrite.h"
  19
  20 #define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION"
  21
  22 const char sign_off_header[] = "Signed-off-by: ";
  23 static const char cherry_picked_prefix[] = "(cherry picked from commit ";
  24 static struct rewritten rewritten;
  25
  26 static GIT_PATH_FUNC(git_path_todo_file, SEQ_TODO_FILE)
  27 static GIT_PATH_FUNC(git_path_opts_file, SEQ_OPTS_FILE)
  28 static GIT_PATH_FUNC(git_path_seq_dir, SEQ_DIR)
  29 static GIT_PATH_FUNC(git_path_head_file, SEQ_HEAD_FILE)
  30
  31 static void finish(struct replay_opts *opts)
  32 {
  33         const char *name;
  34         struct strbuf msg = STRBUF_INIT;
  35
  36         if (opts->action != REPLAY_PICK)
  37                 return;
  38
  39         name = opts->action_name ? opts->action_name : "cherry-pick";
  40
  41         if (!*name)
  42                 return;
  43
  44         strbuf_addf(&msg, "Notes added by 'git %s'", name);
  45         copy_rewrite_notes(&rewritten, name, msg.buf);
  46         run_rewrite_hook(&rewritten, name);
  47         strbuf_release(&msg);
  48 }
  49
  50 static int is_rfc2822_line(const char *buf, int len)
  51 {
  52         int i;
  53
  54         for (i = 0; i < len; i++) {
  55                 int ch = buf[i];
  56                 if (ch == ':')
  57                         return 1;
  58                 if (!isalnum(ch) && ch != '-')
  59                         break;
  60         }
  61
  62         return 0;
  63 }
  64
  65 static int is_cherry_picked_from_line(const char *buf, int len)
  66 {
  67         /*
  68          * We only care that it looks roughly like (cherry picked from ...)
  69          */
  70         return len > strlen(cherry_picked_prefix) + 1 &&
  71                 starts_with(buf, cherry_picked_prefix) && buf[len - 1] == ')';
  72 }
  73
  74 /*
  75  * Returns 0 for non-conforming footer
  76  * Returns 1 for conforming footer
  77  * Returns 2 when sob exists within conforming footer
  78  * Returns 3 when sob exists within conforming footer as last entry
  79  */
  80 static int has_conforming_footer(struct strbuf *sb, struct strbuf *sob,
  81         int ignore_footer)
  82 {
  83         char prev;
  84         int i, k;
  85         int len = sb->len - ignore_footer;
  86         const char *buf = sb->buf;
  87         int found_sob = 0;
  88
  89         /* footer must end with newline */
  90         if (!len || buf[len - 1] != '\n')
  91                 return 0;
  92
  93         prev = '\0';
  94         for (i = len - 1; i > 0; i--) {
  95                 char ch = buf[i];
  96                 if (prev == '\n' && ch == '\n') /* paragraph break */
  97                         break;
  98                 prev = ch;
  99         }
 100
 101         /* require at least one blank line */
 102         if (prev != '\n' || buf[i] != '\n')
 103                 return 0;
 104
 105         /* advance to start of last paragraph */
 106         while (i < len - 1 && buf[i] == '\n')
 107                 i++;
 108
 109         for (; i < len; i = k) {
 110                 int found_rfc2822;
 111
 112                 for (k = i; k < len && buf[k] != '\n'; k++)
 113                         ; /* do nothing */
 114                 k++;
 115
 116                 found_rfc2822 = is_rfc2822_line(buf + i, k - i - 1);
 117                 if (found_rfc2822 && sob &&
 118                     !strncmp(buf + i, sob->buf, sob->len))
 119                         found_sob = k;
 120
 121                 if (!(found_rfc2822 ||
 122                       is_cherry_picked_from_line(buf + i, k - i - 1)))
 123                         return 0;
 124         }
 125         if (found_sob == i)
 126                 return 3;
 127         if (found_sob)
 128                 return 2;
 129         return 1;
 130 }
 131
 132 static void remove_sequencer_state(void)
 133 {
 134         struct strbuf seq_dir = STRBUF_INIT;
 135
 136         strbuf_addf(&seq_dir, "%s", git_path(SEQ_DIR));
 137         remove_dir_recursively(&seq_dir, 0);
 138         strbuf_release(&seq_dir);
 139 }
 140
 141 static const char *action_name(const struct replay_opts *opts)
 142 {
 143         return opts->action == REPLAY_REVERT ? "revert" : "cherry-pick";
 144 }
 145
 146 struct commit_message {
 147         char *parent_label;
 148         const char *label;
 149         const char *subject;
 150         const char *message;
 151 };
 152
 153 static int get_message(struct commit *commit, struct commit_message *out)
 154 {
 155         const char *abbrev, *subject;
 156         int abbrev_len, subject_len;
 157         char *q;
 158
 159         if (!git_commit_encoding)
 160                 git_commit_encoding = "UTF-8";
 161
 162         out->message = logmsg_reencode(commit, NULL, git_commit_encoding);
 163         abbrev = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV);
 164         abbrev_len = strlen(abbrev);
 165
 166         subject_len = find_commit_subject(out->message, &subject);
 167
 168         out->parent_label = xmalloc(strlen("parent of ") + abbrev_len +
 169                               strlen("... ") + subject_len + 1);
 170         q = out->parent_label;
 171         q = mempcpy(q, "parent of ", strlen("parent of "));
 172         out->label = q;
 173         q = mempcpy(q, abbrev, abbrev_len);
 174         q = mempcpy(q, "... ", strlen("... "));
 175         out->subject = q;
 176         q = mempcpy(q, subject, subject_len);
 177         *q = '\0';
 178         return 0;
 179 }
 180
 181 static void free_message(struct commit *commit, struct commit_message *msg)
 182 {
 183         free(msg->parent_label);
 184         unuse_commit_buffer(commit, msg->message);
 185 }
 186
 187 static void print_advice(int show_hint, struct replay_opts *opts)
 188 {
 189         char *msg = getenv("GIT_CHERRY_PICK_HELP");
 190
 191         if (msg) {
 192                 fprintf(stderr, "%s\n", msg);
 193                 /*
 194                  * A conflict has occurred but the porcelain
 195                  * (typically rebase --interactive) wants to take care
 196                  * of the commit itself so remove CHERRY_PICK_HEAD
 197                  */
 198                 unlink(git_path_cherry_pick_head());
 199                 return;
 200         }
 201
 202         if (show_hint) {
 203                 if (opts->no_commit)
 204                         advise(_("after resolving the conflicts, mark the corrected paths\n"
 205                                  "with 'git add <paths>' or 'git rm <paths>'"));
 206                 else
 207                         advise(_("after resolving the conflicts, mark the corrected paths\n"
 208                                  "with 'git add <paths>' or 'git rm <paths>'\n"
 209                                  "and commit the result with 'git commit'"));
 210         }
 211 }
 212
 213 static void write_message(struct strbuf *msgbuf, const char *filename)
 214 {
 215         static struct lock_file msg_file;
 216
 217         int msg_fd = hold_lock_file_for_update(&msg_file, filename,
 218                                                LOCK_DIE_ON_ERROR);
 219         if (write_in_full(msg_fd, msgbuf->buf, msgbuf->len) < 0)
 220                 die_errno(_("Could not write to %s"), filename);
 221         strbuf_release(msgbuf);
 222         if (commit_lock_file(&msg_file) < 0)
 223                 die(_("Error wrapping up %s"), filename);
 224 }
 225
 226 static struct tree *empty_tree(void)
 227 {
 228         return lookup_tree(EMPTY_TREE_SHA1_BIN);
 229 }
 230
 231 static int error_dirty_index(struct replay_opts *opts)
 232 {
 233         if (read_cache_unmerged())
 234                 return error_resolve_conflict(action_name(opts));
 235
 236         /* Different translation strings for cherry-pick and revert */
 237         if (opts->action == REPLAY_PICK)
 238                 error(_("Your local changes would be overwritten by cherry-pick."));
 239         else
 240                 error(_("Your local changes would be overwritten by revert."));
 241
 242         if (advice_commit_before_merge)
 243                 advise(_("Commit your changes or stash them to proceed."));
 244         return -1;
 245 }
 246
 247 static int fast_forward_to(const unsigned char *to, const unsigned char *from,
 248                         int unborn, struct replay_opts *opts)
 249 {
 250         struct ref_transaction *transaction;
 251         struct strbuf sb = STRBUF_INIT;
 252         struct strbuf err = STRBUF_INIT;
 253
 254         read_cache();
 255         if (checkout_fast_forward(from, to, 1))
 256                 exit(128); /* the callee should have complained already */
 257
 258         strbuf_addf(&sb, "%s: fast-forward", action_name(opts));
 259
 260         transaction = ref_transaction_begin(&err);
 261         if (!transaction ||
 262             ref_transaction_update(transaction, "HEAD",
 263                                    to, unborn ? null_sha1 : from,
 264                                    0, sb.buf, &err) ||
 265             ref_transaction_commit(transaction, &err)) {
 266                 ref_transaction_free(transaction);
 267                 error("%s", err.buf);
 268                 strbuf_release(&sb);
 269                 strbuf_release(&err);
 270                 return -1;
 271         }
 272
 273         strbuf_release(&sb);
 274         strbuf_release(&err);
 275         ref_transaction_free(transaction);
 276         return 0;
 277 }
 278
 279 void append_conflicts_hint(struct strbuf *msgbuf)
 280 {
 281         int i;
 282
 283         strbuf_addch(msgbuf, '\n');
 284         strbuf_commented_addf(msgbuf, "Conflicts:\n");
 285         for (i = 0; i < active_nr;) {
 286                 const struct cache_entry *ce = active_cache[i++];
 287                 if (ce_stage(ce)) {
 288                         strbuf_commented_addf(msgbuf, "\t%s\n", ce->name);
 289                         while (i < active_nr && !strcmp(ce->name,
 290                                                         active_cache[i]->name))
 291                                 i++;
 292                 }
 293         }
 294 }
 295
 296 static int do_recursive_merge(struct commit *base, struct commit *next,
 297                               const char *base_label, const char *next_label,
 298                               unsigned char *head, struct strbuf *msgbuf,
 299                               struct replay_opts *opts)
 300 {
 301         struct merge_options o;
 302         struct tree *result, *next_tree, *base_tree, *head_tree;
 303         int clean;
 304         const char **xopt;
 305         static struct lock_file index_lock;
 306
 307         hold_locked_index(&index_lock, 1);
 308
 309         read_cache();
 310
 311         init_merge_options(&o);
 312         o.ancestor = base ? base_label : "(empty tree)";
 313         o.branch1 = "HEAD";
 314         o.branch2 = next ? next_label : "(empty tree)";
 315
 316         head_tree = parse_tree_indirect(head);
 317         next_tree = next ? next->tree : empty_tree();
 318         base_tree = base ? base->tree : empty_tree();
 319
 320         for (xopt = opts->xopts; xopt != opts->xopts + opts->xopts_nr; xopt++)
 321                 parse_merge_opt(&o, *xopt);
 322
 323         clean = merge_trees(&o,
 324                             head_tree,
 325                             next_tree, base_tree, &result);
 326
 327         if (active_cache_changed &&
 328             write_locked_index(&the_index, &index_lock, COMMIT_LOCK))
 329                 /* TRANSLATORS: %s will be "revert" or "cherry-pick" */
 330                 die(_("%s: Unable to write new index file"), action_name(opts));
 331         rollback_lock_file(&index_lock);
 332
 333         if (opts->signoff)
 334                 append_signoff(msgbuf, 0, 0);
 335
 336         if (!clean)
 337                 append_conflicts_hint(msgbuf);
 338
 339         return !clean;
 340 }
 341
 342 static int is_index_unchanged(void)
 343 {
 344         unsigned char head_sha1[20];
 345         struct commit *head_commit;
 346
 347         if (!resolve_ref_unsafe("HEAD", RESOLVE_REF_READING, head_sha1, NULL))
 348                 return error(_("Could not resolve HEAD commit\n"));
 349
 350         head_commit = lookup_commit(head_sha1);
 351
 352         /*
 353          * If head_commit is NULL, check_commit, called from
 354          * lookup_commit, would have indicated that head_commit is not
 355          * a commit object already.  parse_commit() will return failure
 356          * without further complaints in such a case.  Otherwise, if
 357          * the commit is invalid, parse_commit() will complain.  So
 358          * there is nothing for us to say here.  Just return failure.
 359          */
 360         if (parse_commit(head_commit))
 361                 return -1;
 362
 363         if (!active_cache_tree)
 364                 active_cache_tree = cache_tree();
 365
 366         if (!cache_tree_fully_valid(active_cache_tree))
 367                 if (cache_tree_update(&the_index, 0))
 368                         return error(_("Unable to update cache tree\n"));
 369
 370         return !hashcmp(active_cache_tree->sha1, head_commit->tree->object.sha1);
 371 }
 372
 373 /*
 374  * If we are cherry-pick, and if the merge did not result in
 375  * hand-editing, we will hit this commit and inherit the original
 376  * author date and name.
 377  * If we are revert, or if our cherry-pick results in a hand merge,
 378  * we had better say that the current user is responsible for that.
 379  */
 380 static int run_git_commit(const char *defmsg, struct replay_opts *opts,
 381                           int allow_empty)
 382 {
 383         struct argv_array array;
 384         int rc;
 385         const char *value;
 386
 387         argv_array_init(&array);
 388         argv_array_push(&array, "commit");
 389         argv_array_push(&array, "-n");
 390         if (opts->quiet)
 391                 argv_array_push(&array, "-q");
 392
 393         if (opts->gpg_sign)
 394                 argv_array_pushf(&array, "-S%s", opts->gpg_sign);
 395         if (opts->signoff)
 396                 argv_array_push(&array, "-s");
 397         if (!opts->edit) {
 398                 argv_array_push(&array, "-F");
 399                 argv_array_push(&array, defmsg);
 400                 if (!opts->signoff &&
 401                     !opts->record_origin &&
 402                     git_config_get_value("commit.cleanup", &value))
 403                         argv_array_push(&array, "--cleanup=verbatim");
 404         }
 405
 406         if (allow_empty)
 407                 argv_array_push(&array, "--allow-empty");
 408
 409         if (opts->allow_empty_message)
 410                 argv_array_push(&array, "--allow-empty-message");
 411
 412         rc = run_command_v_opt(array.argv, RUN_GIT_CMD);
 413         argv_array_clear(&array);
 414         return rc;
 415 }
 416
 417 static int is_original_commit_empty(struct commit *commit)
 418 {
 419         const unsigned char *ptree_sha1;
 420
 421         if (parse_commit(commit))
 422                 return error(_("Could not parse commit %s\n"),
 423                              sha1_to_hex(commit->object.sha1));
 424         if (commit->parents) {
 425                 struct commit *parent = commit->parents->item;
 426                 if (parse_commit(parent))
 427                         return error(_("Could not parse parent commit %s\n"),
 428                                 sha1_to_hex(parent->object.sha1));
 429                 ptree_sha1 = parent->tree->object.sha1;
 430         } else {
 431                 ptree_sha1 = EMPTY_TREE_SHA1_BIN; /* commit is root */
 432         }
 433
 434         return !hashcmp(ptree_sha1, commit->tree->object.sha1);
 435 }
 436
 437 /*
 438  * Do we run "git commit" with "--allow-empty"?
 439  */
 440 static int allow_empty(struct replay_opts *opts, struct commit *commit)
 441 {
 442         int index_unchanged, empty_commit;
 443
 444         /*
 445          * Three cases:
 446          *
 447          * (1) we do not allow empty at all and error out.
 448          *
 449          * (2) we allow ones that were initially empty, but
 450          * forbid the ones that become empty;
 451          *
 452          * (3) we allow both.
 453          */
 454         if (!opts->allow_empty)
 455                 return 0; /* let "git commit" barf as necessary */
 456
 457         index_unchanged = is_index_unchanged();
 458         if (index_unchanged < 0)
 459                 return index_unchanged;
 460         if (!index_unchanged)
 461                 return 0; /* we do not have to say --allow-empty */
 462
 463         if (opts->keep_redundant_commits)
 464                 return 1;
 465
 466         empty_commit = is_original_commit_empty(commit);
 467         if (empty_commit < 0)
 468                 return empty_commit;
 469         if (!empty_commit)
 470                 return 0;
 471         else
 472                 return 1;
 473 }
 474
 475 static int do_pick_commit(struct commit *commit, struct replay_opts *opts)
 476 {
 477         unsigned char head[20];
 478         struct commit *base, *next, *parent;
 479         const char *base_label, *next_label;
 480         struct commit_message msg = { NULL, NULL, NULL, NULL };
 481         struct strbuf msgbuf = STRBUF_INIT;
 482         int res, unborn = 0, allow;
 483
 484         if (opts->no_commit) {
 485                 /*
 486                  * We do not intend to commit immediately.  We just want to
 487                  * merge the differences in, so let's compute the tree
 488                  * that represents the "current" state for merge-recursive
 489                  * to work on.
 490                  */
 491                 if (write_cache_as_tree(head, 0, NULL))
 492                         die (_("Your index file is unmerged."));
 493         } else {
 494                 unborn = get_sha1("HEAD", head);
 495                 if (unborn)
 496                         hashcpy(head, EMPTY_TREE_SHA1_BIN);
 497                 if (index_differs_from(unborn ? EMPTY_TREE_SHA1_HEX : "HEAD", 0))
 498                         return error_dirty_index(opts);
 499         }
 500         discard_cache();
 501
 502         if (!commit->parents) {
 503                 parent = NULL;
 504         }
 505         else if (commit->parents->next) {
 506                 /* Reverting or cherry-picking a merge commit */
 507                 int cnt;
 508                 struct commit_list *p;
 509
 510                 if (!opts->mainline)
 511                         return error(_("Commit %s is a merge but no -m option was given."),
 512                                 sha1_to_hex(commit->object.sha1));
 513
 514                 for (cnt = 1, p = commit->parents;
 515                      cnt != opts->mainline && p;
 516                      cnt++)
 517                         p = p->next;
 518                 if (cnt != opts->mainline || !p)
 519                         return error(_("Commit %s does not have parent %d"),
 520                                 sha1_to_hex(commit->object.sha1), opts->mainline);
 521                 parent = p->item;
 522         } else if (0 < opts->mainline)
 523                 return error(_("Mainline was specified but commit %s is not a merge."),
 524                         sha1_to_hex(commit->object.sha1));
 525         else
 526                 parent = commit->parents->item;
 527
 528         if (opts->allow_ff &&
 529             ((parent && !hashcmp(parent->object.sha1, head)) ||
 530              (!parent && unborn)))
 531                 return fast_forward_to(commit->object.sha1, head, unborn, opts);
 532
 533         if (parent && parse_commit(parent) < 0)
 534                 /* TRANSLATORS: The first %s will be "revert" or
 535                    "cherry-pick", the second %s a SHA1 */
 536                 return error(_("%s: cannot parse parent commit %s"),
 537                         action_name(opts), sha1_to_hex(parent->object.sha1));
 538
 539         if (get_message(commit, &msg) != 0)
 540                 return error(_("Cannot get commit message for %s"),
 541                         sha1_to_hex(commit->object.sha1));
 542
 543         /*
 544          * "commit" is an existing commit.  We would want to apply
 545          * the difference it introduces since its first parent "prev"
 546          * on top of the current HEAD if we are cherry-pick.  Or the
 547          * reverse of it if we are revert.
 548          */
 549
 550         if (opts->action == REPLAY_REVERT) {
 551                 base = commit;
 552                 base_label = msg.label;
 553                 next = parent;
 554                 next_label = msg.parent_label;
 555                 strbuf_addstr(&msgbuf, "Revert \"");
 556                 strbuf_addstr(&msgbuf, msg.subject);
 557                 strbuf_addstr(&msgbuf, "\"\n\nThis reverts commit ");
 558                 strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));
 559
 560                 if (commit->parents && commit->parents->next) {
 561                         strbuf_addstr(&msgbuf, ", reversing\nchanges made to ");
 562                         strbuf_addstr(&msgbuf, sha1_to_hex(parent->object.sha1));
 563                 }
 564                 strbuf_addstr(&msgbuf, ".\n");
 565         } else {
 566                 const char *p;
 567
 568                 base = parent;
 569                 base_label = msg.parent_label;
 570                 next = commit;
 571                 next_label = msg.label;
 572
 573                 /*
 574                  * Append the commit log message to msgbuf; it starts
 575                  * after the tree, parent, author, committer
 576                  * information followed by "\n\n".
 577                  */
 578                 p = strstr(msg.message, "\n\n");
 579                 if (p) {
 580                         p += 2;
 581                         strbuf_addstr(&msgbuf, p);
 582                 }
 583
 584                 if (opts->record_origin) {
 585                         if (!has_conforming_footer(&msgbuf, NULL, 0))
 586                                 strbuf_addch(&msgbuf, '\n');
 587                         strbuf_addstr(&msgbuf, cherry_picked_prefix);
 588                         strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));
 589                         strbuf_addstr(&msgbuf, ")\n");
 590                 }
 591         }
 592
 593         if (!opts->strategy || !strcmp(opts->strategy, "recursive") || opts->action == REPLAY_REVERT) {
 594                 res = do_recursive_merge(base, next, base_label, next_label,
 595                                          head, &msgbuf, opts);
 596                 write_message(&msgbuf, git_path_merge_msg());
 597         } else {
 598                 struct commit_list *common = NULL;
 599                 struct commit_list *remotes = NULL;
 600
 601                 write_message(&msgbuf, git_path_merge_msg());
 602
 603                 commit_list_insert(base, &common);
 604                 commit_list_insert(next, &remotes);
 605                 res = try_merge_command(opts->strategy, opts->xopts_nr, opts->xopts,
 606                                         common, sha1_to_hex(head), remotes);
 607                 free_commit_list(common);
 608                 free_commit_list(remotes);
 609         }
 610
 611         /*
 612          * If the merge was clean or if it failed due to conflict, we write
 613          * CHERRY_PICK_HEAD for the subsequent invocation of commit to use.
 614          * However, if the merge did not even start, then we don't want to
 615          * write it at all.
 616          */
 617         if (opts->action == REPLAY_PICK && !opts->no_commit && (res == 0 || res == 1))
 618                 update_ref(NULL, "CHERRY_PICK_HEAD", commit->object.sha1, NULL,
 619                            REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 620         if (opts->action == REPLAY_REVERT && ((opts->no_commit && res == 0) || res == 1))
 621                 update_ref(NULL, "REVERT_HEAD", commit->object.sha1, NULL,
 622                            REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 623
 624         if (res) {
 625                 error(opts->action == REPLAY_REVERT
 626                       ? _("could not revert %s... %s")
 627                       : _("could not apply %s... %s"),
 628                       find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV),
 629                       msg.subject);
 630                 print_advice(res == 1, opts);
 631                 rerere(opts->allow_rerere_auto);
 632                 goto leave;
 633         }
 634
 635         if (opts->skip_empty && is_index_unchanged() == 1) {
 636                 if (!opts->quiet)
 637                         warning(_("skipping %s... %s"),
 638                                 find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV),
 639                                 msg.subject);
 640                 goto leave;
 641         }
 642         allow = allow_empty(opts, commit);
 643         if (allow < 0) {
 644                 res = allow;
 645                 goto leave;
 646         }
 647         if (!opts->no_commit)
 648                 res = run_git_commit(git_path_merge_msg(), opts, allow);
 649
 650         if (!res && opts->action == REPLAY_PICK) {
 651                 unsigned char to[20];
 652
 653                 if (read_ref("HEAD", to))
 654                         goto leave;
 655
 656                 add_rewritten(&rewritten, commit->object.sha1, to);
 657         }
 658 leave:
 659         free_message(commit, &msg);
 660
 661         return res;
 662 }
 663
 664 static void prepare_revs(struct replay_opts *opts)
 665 {
 666         /*
 667          * picking (but not reverting) ranges (but not individual revisions)
 668          * should be done in reverse
 669          */
 670         if (opts->action == REPLAY_PICK && !opts->revs->no_walk)
 671                 opts->revs->reverse ^= 1;
 672
 673         if (prepare_revision_walk(opts->revs))
 674                 die(_("revision walk setup failed"));
 675
 676         if (!opts->revs->commits && !opts->quiet)
 677                 error(_("empty commit set passed"));
 678 }
 679
 680 static void read_and_refresh_cache(struct replay_opts *opts)
 681 {
 682         static struct lock_file index_lock;
 683         int index_fd = hold_locked_index(&index_lock, 0);
 684         if (read_index_preload(&the_index, NULL) < 0)
 685                 die(_("git %s: failed to read the index"), action_name(opts));
 686         refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED, NULL, NULL, NULL);
 687         if (the_index.cache_changed && index_fd >= 0) {
 688                 if (write_locked_index(&the_index, &index_lock, COMMIT_LOCK))
 689                         die(_("git %s: failed to refresh the index"), action_name(opts));
 690         }
 691         rollback_lock_file(&index_lock);
 692 }
 693
 694 static int format_todo(struct strbuf *buf, struct commit_list *todo_list,
 695                 struct replay_opts *opts)
 696 {
 697         struct commit_list *cur = NULL;
 698         const char *sha1_abbrev = NULL;
 699         const char *action_str = opts->action == REPLAY_REVERT ? "revert" : "pick";
 700         const char *subject;
 701         int subject_len;
 702
 703         for (cur = todo_list; cur; cur = cur->next) {
 704                 const char *commit_buffer = get_commit_buffer(cur->item, NULL);
 705                 sha1_abbrev = find_unique_abbrev(cur->item->object.sha1, DEFAULT_ABBREV);
 706                 subject_len = find_commit_subject(commit_buffer, &subject);
 707                 strbuf_addf(buf, "%s %s %.*s\n", action_str, sha1_abbrev,
 708                         subject_len, subject);
 709                 unuse_commit_buffer(cur->item, commit_buffer);
 710         }
 711         return 0;
 712 }
 713
 714 static struct commit *parse_insn_line(char *bol, char *eol, struct replay_opts *opts)
 715 {
 716         unsigned char commit_sha1[20];
 717         enum replay_action action;
 718         char *end_of_object_name;
 719         int saved, status, padding;
 720
 721         if (starts_with(bol, "pick")) {
 722                 action = REPLAY_PICK;
 723                 bol += strlen("pick");
 724         } else if (starts_with(bol, "revert")) {
 725                 action = REPLAY_REVERT;
 726                 bol += strlen("revert");
 727         } else
 728                 return NULL;
 729
 730         /* Eat up extra spaces/ tabs before object name */
 731         padding = strspn(bol, " \t");
 732         if (!padding)
 733                 return NULL;
 734         bol += padding;
 735
 736         end_of_object_name = bol + strcspn(bol, " \t\n");
 737         saved = *end_of_object_name;
 738         *end_of_object_name = '\0';
 739         status = get_sha1(bol, commit_sha1);
 740         *end_of_object_name = saved;
 741
 742         /*
 743          * Verify that the action matches up with the one in
 744          * opts; we don't support arbitrary instructions
 745          */
 746         if (action != opts->action) {
 747                 const char *action_str;
 748                 action_str = action == REPLAY_REVERT ? "revert" : "cherry-pick";
 749                 error(_("Cannot %s during a %s"), action_str, action_name(opts));
 750                 return NULL;
 751         }
 752
 753         if (status < 0)
 754                 return NULL;
 755
 756         return lookup_commit_reference(commit_sha1);
 757 }
 758
 759 static int parse_insn_buffer(char *buf, struct commit_list **todo_list,
 760                         struct replay_opts *opts)
 761 {
 762         struct commit_list **next = todo_list;
 763         struct commit *commit;
 764         char *p = buf;
 765         int i;
 766
 767         for (i = 1; *p; i++) {
 768                 char *eol = strchrnul(p, '\n');
 769                 commit = parse_insn_line(p, eol, opts);
 770                 if (!commit)
 771                         return error(_("Could not parse line %d."), i);
 772                 next = commit_list_append(commit, next);
 773                 p = *eol ? eol + 1 : eol;
 774         }
 775         if (!*todo_list)
 776                 return error(_("No commits parsed."));
 777         return 0;
 778 }
 779
 780 static void read_populate_todo(struct commit_list **todo_list,
 781                         struct replay_opts *opts)
 782 {
 783         struct strbuf buf = STRBUF_INIT;
 784         int fd, res;
 785
 786         fd = open(git_path_todo_file(), O_RDONLY);
 787         if (fd < 0)
 788                 die_errno(_("Could not open %s"), git_path_todo_file());
 789         if (strbuf_read(&buf, fd, 0) < 0) {
 790                 close(fd);
 791                 strbuf_release(&buf);
 792                 die(_("Could not read %s."), git_path_todo_file());
 793         }
 794         close(fd);
 795
 796         res = parse_insn_buffer(buf.buf, todo_list, opts);
 797         strbuf_release(&buf);
 798         if (res)
 799                 die(_("Unusable instruction sheet: %s"), git_path_todo_file());
 800 }
 801
 802 static int populate_opts_cb(const char *key, const char *value, void *data)
 803 {
 804         struct replay_opts *opts = data;
 805         int error_flag = 1;
 806
 807         if (!value)
 808                 error_flag = 0;
 809         else if (!strcmp(key, "options.no-commit"))
 810                 opts->no_commit = git_config_bool_or_int(key, value, &error_flag);
 811         else if (!strcmp(key, "options.edit"))
 812                 opts->edit = git_config_bool_or_int(key, value, &error_flag);
 813         else if (!strcmp(key, "options.signoff"))
 814                 opts->signoff = git_config_bool_or_int(key, value, &error_flag);
 815         else if (!strcmp(key, "options.record-origin"))
 816                 opts->record_origin = git_config_bool_or_int(key, value, &error_flag);
 817         else if (!strcmp(key, "options.allow-ff"))
 818                 opts->allow_ff = git_config_bool_or_int(key, value, &error_flag);
 819         else if (!strcmp(key, "options.mainline"))
 820                 opts->mainline = git_config_int(key, value);
 821         else if (!strcmp(key, "options.strategy"))
 822                 git_config_string(&opts->strategy, key, value);
 823         else if (!strcmp(key, "options.gpg-sign"))
 824                 git_config_string(&opts->gpg_sign, key, value);
 825         else if (!strcmp(key, "options.strategy-option")) {
 826                 ALLOC_GROW(opts->xopts, opts->xopts_nr + 1, opts->xopts_alloc);
 827                 opts->xopts[opts->xopts_nr++] = xstrdup(value);
 828         } else if (!strcmp(key, "options.allow-rerere-auto"))
 829                 opts->allow_rerere_auto = git_config_int(key, value);
 830         else if (!strcmp(key, "options.action-name"))
 831                 git_config_string(&opts->action_name, key, value);
 832         else
 833                 return error(_("Invalid key: %s"), key);
 834
 835         if (!error_flag)
 836                 return error(_("Invalid value for %s: %s"), key, value);
 837
 838         return 0;
 839 }
 840
 841 static void read_populate_opts(struct replay_opts **opts_ptr)
 842 {
 843         if (!file_exists(git_path_opts_file()))
 844                 return;
 845         if (git_config_from_file(populate_opts_cb, git_path_opts_file(), *opts_ptr) < 0)
 846                 die(_("Malformed options sheet: %s"), git_path_opts_file());
 847 }
 848
 849 static void walk_revs_populate_todo(struct commit_list **todo_list,
 850                                 struct replay_opts *opts)
 851 {
 852         struct commit *commit;
 853         struct commit_list **next;
 854
 855         prepare_revs(opts);
 856
 857         next = todo_list;
 858         while ((commit = get_revision(opts->revs)))
 859                 next = commit_list_append(commit, next);
 860 }
 861
 862 static int create_seq_dir(void)
 863 {
 864         if (file_exists(git_path_seq_dir())) {
 865                 error(_("a cherry-pick or revert is already in progress"));
 866                 advise(_("try \"git cherry-pick (--continue | --quit | --abort)\""));
 867                 return -1;
 868         }
 869         else if (mkdir(git_path_seq_dir(), 0777) < 0)
 870                 die_errno(_("Could not create sequencer directory %s"),
 871                           git_path_seq_dir());
 872         return 0;
 873 }
 874
 875 static void save_head(const char *head)
 876 {
 877         static struct lock_file head_lock;
 878         struct strbuf buf = STRBUF_INIT;
 879         int fd;
 880
 881         fd = hold_lock_file_for_update(&head_lock, git_path_head_file(), LOCK_DIE_ON_ERROR);
 882         strbuf_addf(&buf, "%s\n", head);
 883         if (write_in_full(fd, buf.buf, buf.len) < 0)
 884                 die_errno(_("Could not write to %s"), git_path_head_file());
 885         if (commit_lock_file(&head_lock) < 0)
 886                 die(_("Error wrapping up %s."), git_path_head_file());
 887 }
 888
 889 static int reset_for_rollback(const unsigned char *sha1)
 890 {
 891         const char *argv[4];    /* reset --merge <arg> + NULL */
 892         argv[0] = "reset";
 893         argv[1] = "--merge";
 894         argv[2] = sha1_to_hex(sha1);
 895         argv[3] = NULL;
 896         return run_command_v_opt(argv, RUN_GIT_CMD);
 897 }
 898
 899 static int rollback_single_pick(void)
 900 {
 901         unsigned char head_sha1[20];
 902
 903         if (!file_exists(git_path_cherry_pick_head()) &&
 904             !file_exists(git_path_revert_head()))
 905                 return error(_("no cherry-pick or revert in progress"));
 906         if (read_ref_full("HEAD", 0, head_sha1, NULL))
 907                 return error(_("cannot resolve HEAD"));
 908         if (is_null_sha1(head_sha1))
 909                 return error(_("cannot abort from a branch yet to be born"));
 910         return reset_for_rollback(head_sha1);
 911 }
 912
 913 static int sequencer_rollback(struct replay_opts *opts)
 914 {
 915         FILE *f;
 916         unsigned char sha1[20];
 917         struct strbuf buf = STRBUF_INIT;
 918         struct string_list merge_rr = STRING_LIST_INIT_DUP;
 919
 920         if (setup_rerere(&merge_rr, 0) >= 0) {
 921                 rerere_clear(&merge_rr);
 922                 string_list_clear(&merge_rr, 1);
 923         }
 924
 925         f = fopen(git_path_head_file(), "r");
 926         if (!f && errno == ENOENT) {
 927                 /*
 928                  * There is no multiple-cherry-pick in progress.
 929                  * If CHERRY_PICK_HEAD or REVERT_HEAD indicates
 930                  * a single-cherry-pick in progress, abort that.
 931                  */
 932                 return rollback_single_pick();
 933         }
 934         if (!f)
 935                 return error(_("cannot open %s: %s"), git_path_head_file(),
 936                                                 strerror(errno));
 937         if (strbuf_getline(&buf, f, '\n')) {
 938                 error(_("cannot read %s: %s"), git_path_head_file(),
 939                       ferror(f) ?  strerror(errno) : _("unexpected end of file"));
 940                 fclose(f);
 941                 goto fail;
 942         }
 943         fclose(f);
 944         if (get_sha1_hex(buf.buf, sha1) || buf.buf[40] != '\0') {
 945                 error(_("stored pre-cherry-pick HEAD file '%s' is corrupt"),
 946                         git_path_head_file());
 947                 goto fail;
 948         }
 949         if (reset_for_rollback(sha1))
 950                 goto fail;
 951         remove_sequencer_state();
 952         strbuf_release(&buf);
 953         return 0;
 954 fail:
 955         strbuf_release(&buf);
 956         return -1;
 957 }
 958
 959 static void save_todo(struct commit_list *todo_list, struct replay_opts *opts)
 960 {
 961         static struct lock_file todo_lock;
 962         struct strbuf buf = STRBUF_INIT;
 963         int fd;
 964
 965         fd = hold_lock_file_for_update(&todo_lock, git_path_todo_file(), LOCK_DIE_ON_ERROR);
 966         if (format_todo(&buf, todo_list, opts) < 0)
 967                 die(_("Could not format %s."), git_path_todo_file());
 968         if (write_in_full(fd, buf.buf, buf.len) < 0) {
 969                 strbuf_release(&buf);
 970                 die_errno(_("Could not write to %s"), git_path_todo_file());
 971         }
 972         if (commit_lock_file(&todo_lock) < 0) {
 973                 strbuf_release(&buf);
 974                 die(_("Error wrapping up %s."), git_path_todo_file());
 975         }
 976         strbuf_release(&buf);
 977 }
 978
 979 static void save_opts(struct replay_opts *opts)
 980 {
 981         const char *opts_file = git_path_opts_file();
 982
 983         if (opts->no_commit)
 984                 git_config_set_in_file(opts_file, "options.no-commit", "true");
 985         if (opts->edit)
 986                 git_config_set_in_file(opts_file, "options.edit", "true");
 987         if (opts->signoff)
 988                 git_config_set_in_file(opts_file, "options.signoff", "true");
 989         if (opts->record_origin)
 990                 git_config_set_in_file(opts_file, "options.record-origin", "true");
 991         if (opts->allow_ff)
 992                 git_config_set_in_file(opts_file, "options.allow-ff", "true");
 993         if (opts->mainline) {
 994                 struct strbuf buf = STRBUF_INIT;
 995                 strbuf_addf(&buf, "%d", opts->mainline);
 996                 git_config_set_in_file(opts_file, "options.mainline", buf.buf);
 997                 strbuf_release(&buf);
 998         }
 999         if (opts->strategy)
1000                 git_config_set_in_file(opts_file, "options.strategy", opts->strategy);
1001         if (opts->gpg_sign)
1002                 git_config_set_in_file(opts_file, "options.gpg-sign", opts->gpg_sign);
1003         if (opts->xopts) {
1004                 int i;
1005                 for (i = 0; i < opts->xopts_nr; i++)
1006                         git_config_set_multivar_in_file(opts_file,
1007                                                         "options.strategy-option",
1008                                                         opts->xopts[i], "^$", 0);
1009         }
1010         if (opts->allow_rerere_auto) {
1011                 struct strbuf buf = STRBUF_INIT;
1012                 strbuf_addf(&buf, "%d", opts->allow_rerere_auto);
1013                 git_config_set_in_file(opts_file, "options.allow-rerere-auto", buf.buf);
1014                 strbuf_release(&buf);
1015         }
1016         if (opts->action_name)
1017                 git_config_set_in_file(opts_file, "options.action-name", opts->action_name);
1018 }
1019
1020 static int pick_commits(struct commit_list *todo_list, struct replay_opts *opts)
1021 {
1022         struct commit_list *cur;
1023         int res;
1024
1025         setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
1026         if (opts->allow_ff)
1027                 assert(!(opts->signoff || opts->no_commit ||
1028                                 opts->record_origin || opts->edit));
1029         read_and_refresh_cache(opts);
1030
1031         for (cur = todo_list; cur; cur = cur->next) {
1032                 save_todo(cur, opts);
1033                 res = do_pick_commit(cur->item, opts);
1034                 if (res) {
1035                         if (opts->action == REPLAY_PICK)
1036                                 store_rewritten(&rewritten, git_path(SEQ_REWR_FILE));
1037                         return res;
1038                 }
1039         }
1040
1041         finish(opts);
1042
1043         /*
1044          * Sequence of picks finished successfully; cleanup by
1045          * removing the .git/sequencer directory
1046          */
1047         remove_sequencer_state();
1048         return 0;
1049 }
1050
1051 static int continue_single_pick(void)
1052 {
1053         const char *argv[] = { "commit", NULL };
1054
1055         if (!file_exists(git_path_cherry_pick_head()) &&
1056             !file_exists(git_path_revert_head()))
1057                 return error(_("no cherry-pick or revert in progress"));
1058         return run_command_v_opt(argv, RUN_GIT_CMD);
1059 }
1060
1061 static int sequencer_continue(struct replay_opts *opts, int skip)
1062 {
1063         struct commit_list *todo_list = NULL;
1064
1065         if (!file_exists(git_path_todo_file()))
1066                 return continue_single_pick();
1067         read_populate_opts(&opts);
1068         read_populate_todo(&todo_list, opts);
1069         if (opts->action == REPLAY_PICK)
1070                 load_rewritten(&rewritten, git_path(SEQ_REWR_FILE));
1071
1072         /* Verify that the conflict has been resolved */
1073         if (file_exists(git_path_cherry_pick_head()) ||
1074             file_exists(git_path_revert_head())) {
1075                 int ret = continue_single_pick();
1076                 if (ret)
1077                         return ret;
1078         }
1079         if (index_differs_from("HEAD", 0))
1080                 return error_dirty_index(opts);
1081         if (opts->action == REPLAY_PICK && !skip) {
1082                 unsigned char to[20];
1083                 if (!read_ref("HEAD", to))
1084                         add_rewritten(&rewritten, todo_list->item->object.sha1, to);
1085         }
1086         todo_list = todo_list->next;
1087         return pick_commits(todo_list, opts);
1088 }
1089
1090 static int sequencer_skip(struct replay_opts *opts)
1091 {
1092         const char *argv[3]; /* reset --hard + NULL */
1093         struct string_list merge_rr = STRING_LIST_INIT_DUP;
1094         int ret;
1095
1096         if (setup_rerere(&merge_rr, 0) >= 0) {
1097                 rerere_clear(&merge_rr);
1098                 string_list_clear(&merge_rr, 1);
1099         }
1100
1101         argv[0] = "reset";
1102         argv[1] = "--hard";
1103         argv[2] = NULL;
1104         ret = run_command_v_opt(argv, RUN_GIT_CMD);
1105         if (ret)
1106                 return ret;
1107
1108         discard_cache();
1109         read_cache();
1110
1111         return sequencer_continue(opts, 1);
1112 }
1113
1114 static int single_pick(struct commit *cmit, struct replay_opts *opts)
1115 {
1116         int ret;
1117         setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
1118         ret = do_pick_commit(cmit, opts);
1119         if (ret)
1120                 return ret;
1121         finish(opts);
1122         return 0;
1123 }
1124
1125 int sequencer_pick_revisions(struct replay_opts *opts)
1126 {
1127         struct commit_list *todo_list = NULL;
1128         unsigned char sha1[20];
1129         int i;
1130
1131         if (opts->subcommand == REPLAY_NONE)
1132                 assert(opts->revs);
1133
1134         read_and_refresh_cache(opts);
1135
1136         /*
1137          * Decide what to do depending on the arguments; a fresh
1138          * cherry-pick should be handled differently from an existing
1139          * one that is being continued
1140          */
1141         if (opts->subcommand == REPLAY_REMOVE_STATE) {
1142                 remove_sequencer_state();
1143                 return 0;
1144         }
1145         if (opts->subcommand == REPLAY_ROLLBACK)
1146                 return sequencer_rollback(opts);
1147         if (opts->subcommand == REPLAY_CONTINUE)
1148                 return sequencer_continue(opts, 0);
1149         if (opts->subcommand == REPLAY_SKIP)
1150                 return sequencer_skip(opts);
1151
1152         for (i = 0; i < opts->revs->pending.nr; i++) {
1153                 unsigned char sha1[20];
1154                 const char *name = opts->revs->pending.objects[i].name;
1155
1156                 /* This happens when using --stdin. */
1157                 if (!strlen(name))
1158                         continue;
1159
1160                 if (!get_sha1(name, sha1)) {
1161                         if (!lookup_commit_reference_gently(sha1, 1)) {
1162                                 enum object_type type = sha1_object_info(sha1, NULL);
1163                                 die(_("%s: can't cherry-pick a %s"), name, typename(type));
1164                         }
1165                 } else
1166                         die(_("%s: bad revision"), name);
1167         }
1168
1169         /*
1170          * If we were called as "git cherry-pick <commit>", just
1171          * cherry-pick/revert it, set CHERRY_PICK_HEAD /
1172          * REVERT_HEAD, and don't touch the sequencer state.
1173          * This means it is possible to cherry-pick in the middle
1174          * of a cherry-pick sequence.
1175          */
1176         if (opts->revs->cmdline.nr == 1 &&
1177             opts->revs->cmdline.rev->whence == REV_CMD_REV &&
1178             opts->revs->no_walk &&
1179             !opts->revs->cmdline.rev->flags) {
1180                 struct commit *cmit;
1181                 if (prepare_revision_walk(opts->revs))
1182                         die(_("revision walk setup failed"));
1183                 cmit = get_revision(opts->revs);
1184                 if (!cmit || get_revision(opts->revs))
1185                         die("BUG: expected exactly one commit from walk");
1186                 return single_pick(cmit, opts);
1187         }
1188
1189         /*
1190          * Start a new cherry-pick/ revert sequence; but
1191          * first, make sure that an existing one isn't in
1192          * progress
1193          */
1194
1195         walk_revs_populate_todo(&todo_list, opts);
1196         if (create_seq_dir() < 0)
1197                 return -1;
1198         if (get_sha1("HEAD", sha1)) {
1199                 if (opts->action == REPLAY_REVERT)
1200                         return error(_("Can't revert as initial commit"));
1201                 return error(_("Can't cherry-pick into empty head"));
1202         }
1203         save_head(sha1_to_hex(sha1));
1204         save_opts(opts);
1205         return pick_commits(todo_list, opts);
1206 }
1207
1208 void append_signoff(struct strbuf *msgbuf, int ignore_footer, unsigned flag)
1209 {
1210         unsigned no_dup_sob = flag & APPEND_SIGNOFF_DEDUP;
1211         struct strbuf sob = STRBUF_INIT;
1212         int has_footer;
1213
1214         strbuf_addstr(&sob, sign_off_header);
1215         strbuf_addstr(&sob, fmt_name(getenv("GIT_COMMITTER_NAME"),
1216                                 getenv("GIT_COMMITTER_EMAIL")));
1217         strbuf_addch(&sob, '\n');
1218
1219         /*
1220          * If the whole message buffer is equal to the sob, pretend that we
1221          * found a conforming footer with a matching sob
1222          */
1223         if (msgbuf->len - ignore_footer == sob.len &&
1224             !strncmp(msgbuf->buf, sob.buf, sob.len))
1225                 has_footer = 3;
1226         else
1227                 has_footer = has_conforming_footer(msgbuf, &sob, ignore_footer);
1228
1229         if (!has_footer) {
1230                 const char *append_newlines = NULL;
1231                 size_t len = msgbuf->len - ignore_footer;
1232
1233                 if (!len) {
1234                         /*
1235                          * The buffer is completely empty.  Leave foom for
1236                          * the title and body to be filled in by the user.
1237                          */
1238                         append_newlines = "\n\n";
1239                 } else if (msgbuf->buf[len - 1] != '\n') {
1240                         /*
1241                          * Incomplete line.  Complete the line and add a
1242                          * blank one so that there is an empty line between
1243                          * the message body and the sob.
1244                          */
1245                         append_newlines = "\n\n";
1246                 } else if (len == 1) {
1247                         /*
1248                          * Buffer contains a single newline.  Add another
1249                          * so that we leave room for the title and body.
1250                          */
1251                         append_newlines = "\n";
1252                 } else if (msgbuf->buf[len - 2] != '\n') {
1253                         /*
1254                          * Buffer ends with a single newline.  Add another
1255                          * so that there is an empty line between the message
1256                          * body and the sob.
1257                          */
1258                         append_newlines = "\n";
1259                 } /* else, the buffer already ends with two newlines. */
1260
1261                 if (append_newlines)
1262                         strbuf_splice(msgbuf, msgbuf->len - ignore_footer, 0,
1263                                 append_newlines, strlen(append_newlines));
1264         }
1265
1266         if (has_footer != 3 && (!no_dup_sob || has_footer != 2))
1267                 strbuf_splice(msgbuf, msgbuf->len - ignore_footer, 0,
1268                                 sob.buf, sob.len);
1269
1270         strbuf_release(&sob);
1271 }