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 void finish(struct replay_opts *opts)
  27 {
  28         const char *name;
  29         struct strbuf msg = STRBUF_INIT;
  30
  31         if (opts->action != REPLAY_PICK)
  32                 return;
  33
  34         name = opts->action_name ? opts->action_name : "cherry-pick";
  35
  36         if (!*name)
  37                 return;
  38
  39         strbuf_addf(&msg, "Notes added by 'git %s'", name);
  40         copy_rewrite_notes(&rewritten, name, msg.buf);
  41         run_rewrite_hook(&rewritten, name);
  42         strbuf_release(&msg);
  43 }
  44
  45 static int is_rfc2822_line(const char *buf, int len)
  46 {
  47         int i;
  48
  49         for (i = 0; i < len; i++) {
  50                 int ch = buf[i];
  51                 if (ch == ':')
  52                         return 1;
  53                 if (!isalnum(ch) && ch != '-')
  54                         break;
  55         }
  56
  57         return 0;
  58 }
  59
  60 static int is_cherry_picked_from_line(const char *buf, int len)
  61 {
  62         /*
  63          * We only care that it looks roughly like (cherry picked from ...)
  64          */
  65         return len > strlen(cherry_picked_prefix) + 1 &&
  66                 starts_with(buf, cherry_picked_prefix) && buf[len - 1] == ')';
  67 }
  68
  69 /*
  70  * Returns 0 for non-conforming footer
  71  * Returns 1 for conforming footer
  72  * Returns 2 when sob exists within conforming footer
  73  * Returns 3 when sob exists within conforming footer as last entry
  74  */
  75 static int has_conforming_footer(struct strbuf *sb, struct strbuf *sob,
  76         int ignore_footer)
  77 {
  78         char prev;
  79         int i, k;
  80         int len = sb->len - ignore_footer;
  81         const char *buf = sb->buf;
  82         int found_sob = 0;
  83
  84         /* footer must end with newline */
  85         if (!len || buf[len - 1] != '\n')
  86                 return 0;
  87
  88         prev = '\0';
  89         for (i = len - 1; i > 0; i--) {
  90                 char ch = buf[i];
  91                 if (prev == '\n' && ch == '\n') /* paragraph break */
  92                         break;
  93                 prev = ch;
  94         }
  95
  96         /* require at least one blank line */
  97         if (prev != '\n' || buf[i] != '\n')
  98                 return 0;
  99
 100         /* advance to start of last paragraph */
 101         while (i < len - 1 && buf[i] == '\n')
 102                 i++;
 103
 104         for (; i < len; i = k) {
 105                 int found_rfc2822;
 106
 107                 for (k = i; k < len && buf[k] != '\n'; k++)
 108                         ; /* do nothing */
 109                 k++;
 110
 111                 found_rfc2822 = is_rfc2822_line(buf + i, k - i - 1);
 112                 if (found_rfc2822 && sob &&
 113                     !strncmp(buf + i, sob->buf, sob->len))
 114                         found_sob = k;
 115
 116                 if (!(found_rfc2822 ||
 117                       is_cherry_picked_from_line(buf + i, k - i - 1)))
 118                         return 0;
 119         }
 120         if (found_sob == i)
 121                 return 3;
 122         if (found_sob)
 123                 return 2;
 124         return 1;
 125 }
 126
 127 static void remove_sequencer_state(void)
 128 {
 129         struct strbuf seq_dir = STRBUF_INIT;
 130
 131         strbuf_addf(&seq_dir, "%s", git_path(SEQ_DIR));
 132         remove_dir_recursively(&seq_dir, 0);
 133         strbuf_release(&seq_dir);
 134 }
 135
 136 static const char *action_name(const struct replay_opts *opts)
 137 {
 138         return opts->action == REPLAY_REVERT ? "revert" : "cherry-pick";
 139 }
 140
 141 struct commit_message {
 142         char *parent_label;
 143         const char *label;
 144         const char *subject;
 145         const char *message;
 146 };
 147
 148 static int get_message(struct commit *commit, struct commit_message *out)
 149 {
 150         const char *abbrev, *subject;
 151         int abbrev_len, subject_len;
 152         char *q;
 153
 154         if (!git_commit_encoding)
 155                 git_commit_encoding = "UTF-8";
 156
 157         out->message = logmsg_reencode(commit, NULL, git_commit_encoding);
 158         abbrev = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV);
 159         abbrev_len = strlen(abbrev);
 160
 161         subject_len = find_commit_subject(out->message, &subject);
 162
 163         out->parent_label = xmalloc(strlen("parent of ") + abbrev_len +
 164                               strlen("... ") + subject_len + 1);
 165         q = out->parent_label;
 166         q = mempcpy(q, "parent of ", strlen("parent of "));
 167         out->label = q;
 168         q = mempcpy(q, abbrev, abbrev_len);
 169         q = mempcpy(q, "... ", strlen("... "));
 170         out->subject = q;
 171         q = mempcpy(q, subject, subject_len);
 172         *q = '\0';
 173         return 0;
 174 }
 175
 176 static void free_message(struct commit *commit, struct commit_message *msg)
 177 {
 178         free(msg->parent_label);
 179         unuse_commit_buffer(commit, msg->message);
 180 }
 181
 182 static void write_cherry_pick_head(struct commit *commit, const char *pseudoref)
 183 {
 184         const char *filename;
 185         int fd;
 186         struct strbuf buf = STRBUF_INIT;
 187
 188         strbuf_addf(&buf, "%s\n", sha1_to_hex(commit->object.sha1));
 189
 190         filename = git_path("%s", pseudoref);
 191         fd = open(filename, O_WRONLY | O_CREAT, 0666);
 192         if (fd < 0)
 193                 die_errno(_("Could not open '%s' for writing"), filename);
 194         if (write_in_full(fd, buf.buf, buf.len) != buf.len || close(fd))
 195                 die_errno(_("Could not write to '%s'"), filename);
 196         strbuf_release(&buf);
 197 }
 198
 199 static void print_advice(int show_hint, struct replay_opts *opts)
 200 {
 201         char *msg = getenv("GIT_CHERRY_PICK_HELP");
 202
 203         if (msg) {
 204                 fprintf(stderr, "%s\n", msg);
 205                 /*
 206                  * A conflict has occurred but the porcelain
 207                  * (typically rebase --interactive) wants to take care
 208                  * of the commit itself so remove CHERRY_PICK_HEAD
 209                  */
 210                 unlink(git_path("CHERRY_PICK_HEAD"));
 211                 return;
 212         }
 213
 214         if (show_hint) {
 215                 if (opts->no_commit)
 216                         advise(_("after resolving the conflicts, mark the corrected paths\n"
 217                                  "with 'git add <paths>' or 'git rm <paths>'"));
 218                 else
 219                         advise(_("after resolving the conflicts, mark the corrected paths\n"
 220                                  "with 'git add <paths>' or 'git rm <paths>'\n"
 221                                  "and commit the result with 'git commit'"));
 222         }
 223 }
 224
 225 static void write_message(struct strbuf *msgbuf, const char *filename)
 226 {
 227         static struct lock_file msg_file;
 228
 229         int msg_fd = hold_lock_file_for_update(&msg_file, filename,
 230                                                LOCK_DIE_ON_ERROR);
 231         if (write_in_full(msg_fd, msgbuf->buf, msgbuf->len) < 0)
 232                 die_errno(_("Could not write to %s"), filename);
 233         strbuf_release(msgbuf);
 234         if (commit_lock_file(&msg_file) < 0)
 235                 die(_("Error wrapping up %s"), filename);
 236 }
 237
 238 static struct tree *empty_tree(void)
 239 {
 240         return lookup_tree(EMPTY_TREE_SHA1_BIN);
 241 }
 242
 243 static int error_dirty_index(struct replay_opts *opts)
 244 {
 245         if (read_cache_unmerged())
 246                 return error_resolve_conflict(action_name(opts));
 247
 248         /* Different translation strings for cherry-pick and revert */
 249         if (opts->action == REPLAY_PICK)
 250                 error(_("Your local changes would be overwritten by cherry-pick."));
 251         else
 252                 error(_("Your local changes would be overwritten by revert."));
 253
 254         if (advice_commit_before_merge)
 255                 advise(_("Commit your changes or stash them to proceed."));
 256         return -1;
 257 }
 258
 259 static int fast_forward_to(const unsigned char *to, const unsigned char *from,
 260                         int unborn, struct replay_opts *opts)
 261 {
 262         struct ref_transaction *transaction;
 263         struct strbuf sb = STRBUF_INIT;
 264         struct strbuf err = STRBUF_INIT;
 265
 266         read_cache();
 267         if (checkout_fast_forward(from, to, 1))
 268                 exit(128); /* the callee should have complained already */
 269
 270         strbuf_addf(&sb, "%s: fast-forward", action_name(opts));
 271
 272         transaction = ref_transaction_begin(&err);
 273         if (!transaction ||
 274             ref_transaction_update(transaction, "HEAD",
 275                                    to, unborn ? null_sha1 : from,
 276                                    0, 1, sb.buf, &err) ||
 277             ref_transaction_commit(transaction, &err)) {
 278                 ref_transaction_free(transaction);
 279                 error("%s", err.buf);
 280                 strbuf_release(&sb);
 281                 strbuf_release(&err);
 282                 return -1;
 283         }
 284
 285         strbuf_release(&sb);
 286         strbuf_release(&err);
 287         ref_transaction_free(transaction);
 288         return 0;
 289 }
 290
 291 void append_conflicts_hint(struct strbuf *msgbuf)
 292 {
 293         int i;
 294
 295         strbuf_addch(msgbuf, '\n');
 296         strbuf_commented_addf(msgbuf, "Conflicts:\n");
 297         for (i = 0; i < active_nr;) {
 298                 const struct cache_entry *ce = active_cache[i++];
 299                 if (ce_stage(ce)) {
 300                         strbuf_commented_addf(msgbuf, "\t%s\n", ce->name);
 301                         while (i < active_nr && !strcmp(ce->name,
 302                                                         active_cache[i]->name))
 303                                 i++;
 304                 }
 305         }
 306 }
 307
 308 static int do_recursive_merge(struct commit *base, struct commit *next,
 309                               const char *base_label, const char *next_label,
 310                               unsigned char *head, struct strbuf *msgbuf,
 311                               struct replay_opts *opts)
 312 {
 313         struct merge_options o;
 314         struct tree *result, *next_tree, *base_tree, *head_tree;
 315         int clean;
 316         const char **xopt;
 317         static struct lock_file index_lock;
 318
 319         hold_locked_index(&index_lock, 1);
 320
 321         read_cache();
 322
 323         init_merge_options(&o);
 324         o.ancestor = base ? base_label : "(empty tree)";
 325         o.branch1 = "HEAD";
 326         o.branch2 = next ? next_label : "(empty tree)";
 327
 328         head_tree = parse_tree_indirect(head);
 329         next_tree = next ? next->tree : empty_tree();
 330         base_tree = base ? base->tree : empty_tree();
 331
 332         for (xopt = opts->xopts; xopt != opts->xopts + opts->xopts_nr; xopt++)
 333                 parse_merge_opt(&o, *xopt);
 334
 335         clean = merge_trees(&o,
 336                             head_tree,
 337                             next_tree, base_tree, &result);
 338
 339         if (active_cache_changed &&
 340             write_locked_index(&the_index, &index_lock, COMMIT_LOCK))
 341                 /* TRANSLATORS: %s will be "revert" or "cherry-pick" */
 342                 die(_("%s: Unable to write new index file"), action_name(opts));
 343         rollback_lock_file(&index_lock);
 344
 345         if (opts->signoff)
 346                 append_signoff(msgbuf, 0, 0);
 347
 348         if (!clean)
 349                 append_conflicts_hint(msgbuf);
 350
 351         return !clean;
 352 }
 353
 354 static int is_index_unchanged(void)
 355 {
 356         unsigned char head_sha1[20];
 357         struct commit *head_commit;
 358
 359         if (!resolve_ref_unsafe("HEAD", RESOLVE_REF_READING, head_sha1, NULL))
 360                 return error(_("Could not resolve HEAD commit\n"));
 361
 362         head_commit = lookup_commit(head_sha1);
 363
 364         /*
 365          * If head_commit is NULL, check_commit, called from
 366          * lookup_commit, would have indicated that head_commit is not
 367          * a commit object already.  parse_commit() will return failure
 368          * without further complaints in such a case.  Otherwise, if
 369          * the commit is invalid, parse_commit() will complain.  So
 370          * there is nothing for us to say here.  Just return failure.
 371          */
 372         if (parse_commit(head_commit))
 373                 return -1;
 374
 375         if (!active_cache_tree)
 376                 active_cache_tree = cache_tree();
 377
 378         if (!cache_tree_fully_valid(active_cache_tree))
 379                 if (cache_tree_update(&the_index, 0))
 380                         return error(_("Unable to update cache tree\n"));
 381
 382         return !hashcmp(active_cache_tree->sha1, head_commit->tree->object.sha1);
 383 }
 384
 385 /*
 386  * If we are cherry-pick, and if the merge did not result in
 387  * hand-editing, we will hit this commit and inherit the original
 388  * author date and name.
 389  * If we are revert, or if our cherry-pick results in a hand merge,
 390  * we had better say that the current user is responsible for that.
 391  */
 392 static int run_git_commit(const char *defmsg, struct replay_opts *opts,
 393                           int allow_empty)
 394 {
 395         struct argv_array array;
 396         int rc;
 397
 398         argv_array_init(&array);
 399         argv_array_push(&array, "commit");
 400         argv_array_push(&array, "-n");
 401         if (opts->quiet)
 402                 argv_array_push(&array, "-q");
 403
 404         if (opts->gpg_sign)
 405                 argv_array_pushf(&array, "-S%s", opts->gpg_sign);
 406         if (opts->signoff)
 407                 argv_array_push(&array, "-s");
 408         if (!opts->edit) {
 409                 argv_array_push(&array, "-F");
 410                 argv_array_push(&array, defmsg);
 411         }
 412
 413         if (allow_empty)
 414                 argv_array_push(&array, "--allow-empty");
 415
 416         if (opts->allow_empty_message)
 417                 argv_array_push(&array, "--allow-empty-message");
 418
 419         rc = run_command_v_opt(array.argv, RUN_GIT_CMD);
 420         argv_array_clear(&array);
 421         return rc;
 422 }
 423
 424 static int is_original_commit_empty(struct commit *commit)
 425 {
 426         const unsigned char *ptree_sha1;
 427
 428         if (parse_commit(commit))
 429                 return error(_("Could not parse commit %s\n"),
 430                              sha1_to_hex(commit->object.sha1));
 431         if (commit->parents) {
 432                 struct commit *parent = commit->parents->item;
 433                 if (parse_commit(parent))
 434                         return error(_("Could not parse parent commit %s\n"),
 435                                 sha1_to_hex(parent->object.sha1));
 436                 ptree_sha1 = parent->tree->object.sha1;
 437         } else {
 438                 ptree_sha1 = EMPTY_TREE_SHA1_BIN; /* commit is root */
 439         }
 440
 441         return !hashcmp(ptree_sha1, commit->tree->object.sha1);
 442 }
 443
 444 /*
 445  * Do we run "git commit" with "--allow-empty"?
 446  */
 447 static int allow_empty(struct replay_opts *opts, struct commit *commit)
 448 {
 449         int index_unchanged, empty_commit;
 450
 451         /*
 452          * Three cases:
 453          *
 454          * (1) we do not allow empty at all and error out.
 455          *
 456          * (2) we allow ones that were initially empty, but
 457          * forbid the ones that become empty;
 458          *
 459          * (3) we allow both.
 460          */
 461         if (!opts->allow_empty)
 462                 return 0; /* let "git commit" barf as necessary */
 463
 464         index_unchanged = is_index_unchanged();
 465         if (index_unchanged < 0)
 466                 return index_unchanged;
 467         if (!index_unchanged)
 468                 return 0; /* we do not have to say --allow-empty */
 469
 470         if (opts->keep_redundant_commits)
 471                 return 1;
 472
 473         empty_commit = is_original_commit_empty(commit);
 474         if (empty_commit < 0)
 475                 return empty_commit;
 476         if (!empty_commit)
 477                 return 0;
 478         else
 479                 return 1;
 480 }
 481
 482 static int do_pick_commit(struct commit *commit, struct replay_opts *opts)
 483 {
 484         unsigned char head[20];
 485         struct commit *base, *next, *parent;
 486         const char *base_label, *next_label;
 487         struct commit_message msg = { NULL, NULL, NULL, NULL };
 488         char *defmsg = NULL;
 489         struct strbuf msgbuf = STRBUF_INIT;
 490         int res, unborn = 0, allow;
 491
 492         if (opts->no_commit) {
 493                 /*
 494                  * We do not intend to commit immediately.  We just want to
 495                  * merge the differences in, so let's compute the tree
 496                  * that represents the "current" state for merge-recursive
 497                  * to work on.
 498                  */
 499                 if (write_cache_as_tree(head, 0, NULL))
 500                         die (_("Your index file is unmerged."));
 501         } else {
 502                 unborn = get_sha1("HEAD", head);
 503                 if (unborn)
 504                         hashcpy(head, EMPTY_TREE_SHA1_BIN);
 505                 if (index_differs_from(unborn ? EMPTY_TREE_SHA1_HEX : "HEAD", 0))
 506                         return error_dirty_index(opts);
 507         }
 508         discard_cache();
 509
 510         if (!commit->parents) {
 511                 parent = NULL;
 512         }
 513         else if (commit->parents->next) {
 514                 /* Reverting or cherry-picking a merge commit */
 515                 int cnt;
 516                 struct commit_list *p;
 517
 518                 if (!opts->mainline)
 519                         return error(_("Commit %s is a merge but no -m option was given."),
 520                                 sha1_to_hex(commit->object.sha1));
 521
 522                 for (cnt = 1, p = commit->parents;
 523                      cnt != opts->mainline && p;
 524                      cnt++)
 525                         p = p->next;
 526                 if (cnt != opts->mainline || !p)
 527                         return error(_("Commit %s does not have parent %d"),
 528                                 sha1_to_hex(commit->object.sha1), opts->mainline);
 529                 parent = p->item;
 530         } else if (0 < opts->mainline)
 531                 return error(_("Mainline was specified but commit %s is not a merge."),
 532                         sha1_to_hex(commit->object.sha1));
 533         else
 534                 parent = commit->parents->item;
 535
 536         if (opts->allow_ff &&
 537             ((parent && !hashcmp(parent->object.sha1, head)) ||
 538              (!parent && unborn)))
 539                 return fast_forward_to(commit->object.sha1, head, unborn, opts);
 540
 541         if (parent && parse_commit(parent) < 0)
 542                 /* TRANSLATORS: The first %s will be "revert" or
 543                    "cherry-pick", the second %s a SHA1 */
 544                 return error(_("%s: cannot parse parent commit %s"),
 545                         action_name(opts), sha1_to_hex(parent->object.sha1));
 546
 547         if (get_message(commit, &msg) != 0)
 548                 return error(_("Cannot get commit message for %s"),
 549                         sha1_to_hex(commit->object.sha1));
 550
 551         /*
 552          * "commit" is an existing commit.  We would want to apply
 553          * the difference it introduces since its first parent "prev"
 554          * on top of the current HEAD if we are cherry-pick.  Or the
 555          * reverse of it if we are revert.
 556          */
 557
 558         defmsg = git_pathdup("MERGE_MSG");
 559
 560         if (opts->action == REPLAY_REVERT) {
 561                 base = commit;
 562                 base_label = msg.label;
 563                 next = parent;
 564                 next_label = msg.parent_label;
 565                 strbuf_addstr(&msgbuf, "Revert \"");
 566                 strbuf_addstr(&msgbuf, msg.subject);
 567                 strbuf_addstr(&msgbuf, "\"\n\nThis reverts commit ");
 568                 strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));
 569
 570                 if (commit->parents && commit->parents->next) {
 571                         strbuf_addstr(&msgbuf, ", reversing\nchanges made to ");
 572                         strbuf_addstr(&msgbuf, sha1_to_hex(parent->object.sha1));
 573                 }
 574                 strbuf_addstr(&msgbuf, ".\n");
 575         } else {
 576                 const char *p;
 577
 578                 base = parent;
 579                 base_label = msg.parent_label;
 580                 next = commit;
 581                 next_label = msg.label;
 582
 583                 /*
 584                  * Append the commit log message to msgbuf; it starts
 585                  * after the tree, parent, author, committer
 586                  * information followed by "\n\n".
 587                  */
 588                 p = strstr(msg.message, "\n\n");
 589                 if (p) {
 590                         p += 2;
 591                         strbuf_addstr(&msgbuf, p);
 592                 }
 593
 594                 if (opts->record_origin) {
 595                         if (!has_conforming_footer(&msgbuf, NULL, 0))
 596                                 strbuf_addch(&msgbuf, '\n');
 597                         strbuf_addstr(&msgbuf, cherry_picked_prefix);
 598                         strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));
 599                         strbuf_addstr(&msgbuf, ")\n");
 600                 }
 601         }
 602
 603         if (!opts->strategy || !strcmp(opts->strategy, "recursive") || opts->action == REPLAY_REVERT) {
 604                 res = do_recursive_merge(base, next, base_label, next_label,
 605                                          head, &msgbuf, opts);
 606                 write_message(&msgbuf, defmsg);
 607         } else {
 608                 struct commit_list *common = NULL;
 609                 struct commit_list *remotes = NULL;
 610
 611                 write_message(&msgbuf, defmsg);
 612
 613                 commit_list_insert(base, &common);
 614                 commit_list_insert(next, &remotes);
 615                 res = try_merge_command(opts->strategy, opts->xopts_nr, opts->xopts,
 616                                         common, sha1_to_hex(head), remotes);
 617                 free_commit_list(common);
 618                 free_commit_list(remotes);
 619         }
 620
 621         /*
 622          * If the merge was clean or if it failed due to conflict, we write
 623          * CHERRY_PICK_HEAD for the subsequent invocation of commit to use.
 624          * However, if the merge did not even start, then we don't want to
 625          * write it at all.
 626          */
 627         if (opts->action == REPLAY_PICK && !opts->no_commit && (res == 0 || res == 1))
 628                 write_cherry_pick_head(commit, "CHERRY_PICK_HEAD");
 629         if (opts->action == REPLAY_REVERT && ((opts->no_commit && res == 0) || res == 1))
 630                 write_cherry_pick_head(commit, "REVERT_HEAD");
 631
 632         if (res) {
 633                 error(opts->action == REPLAY_REVERT
 634                       ? _("could not revert %s... %s")
 635                       : _("could not apply %s... %s"),
 636                       find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV),
 637                       msg.subject);
 638                 print_advice(res == 1, opts);
 639                 rerere(opts->allow_rerere_auto);
 640                 goto leave;
 641         }
 642
 643         if (opts->skip_empty && is_index_unchanged() == 1) {
 644                 if (!opts->quiet)
 645                         warning(_("skipping %s... %s"),
 646                                 find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV),
 647                                 msg.subject);
 648                 goto leave;
 649         }
 650         allow = allow_empty(opts, commit);
 651         if (allow < 0) {
 652                 res = allow;
 653                 goto leave;
 654         }
 655         if (!opts->no_commit)
 656                 res = run_git_commit(defmsg, opts, allow);
 657
 658         if (!res && opts->action == REPLAY_PICK) {
 659                 unsigned char to[20];
 660
 661                 if (read_ref("HEAD", to))
 662                         goto leave;
 663
 664                 add_rewritten(&rewritten, commit->object.sha1, to);
 665         }
 666 leave:
 667         free_message(commit, &msg);
 668         free(defmsg);
 669
 670         return res;
 671 }
 672
 673 static void prepare_revs(struct replay_opts *opts)
 674 {
 675         /*
 676          * picking (but not reverting) ranges (but not individual revisions)
 677          * should be done in reverse
 678          */
 679         if (opts->action == REPLAY_PICK && !opts->revs->no_walk)
 680                 opts->revs->reverse ^= 1;
 681
 682         if (prepare_revision_walk(opts->revs))
 683                 die(_("revision walk setup failed"));
 684
 685         if (!opts->revs->commits && !opts->quiet)
 686                 error(_("empty commit set passed"));
 687 }
 688
 689 static void read_and_refresh_cache(struct replay_opts *opts)
 690 {
 691         static struct lock_file index_lock;
 692         int index_fd = hold_locked_index(&index_lock, 0);
 693         if (read_index_preload(&the_index, NULL) < 0)
 694                 die(_("git %s: failed to read the index"), action_name(opts));
 695         refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED, NULL, NULL, NULL);
 696         if (the_index.cache_changed && index_fd >= 0) {
 697                 if (write_locked_index(&the_index, &index_lock, COMMIT_LOCK))
 698                         die(_("git %s: failed to refresh the index"), action_name(opts));
 699         }
 700         rollback_lock_file(&index_lock);
 701 }
 702
 703 static int format_todo(struct strbuf *buf, struct commit_list *todo_list,
 704                 struct replay_opts *opts)
 705 {
 706         struct commit_list *cur = NULL;
 707         const char *sha1_abbrev = NULL;
 708         const char *action_str = opts->action == REPLAY_REVERT ? "revert" : "pick";
 709         const char *subject;
 710         int subject_len;
 711
 712         for (cur = todo_list; cur; cur = cur->next) {
 713                 const char *commit_buffer = get_commit_buffer(cur->item, NULL);
 714                 sha1_abbrev = find_unique_abbrev(cur->item->object.sha1, DEFAULT_ABBREV);
 715                 subject_len = find_commit_subject(commit_buffer, &subject);
 716                 strbuf_addf(buf, "%s %s %.*s\n", action_str, sha1_abbrev,
 717                         subject_len, subject);
 718                 unuse_commit_buffer(cur->item, commit_buffer);
 719         }
 720         return 0;
 721 }
 722
 723 static struct commit *parse_insn_line(char *bol, char *eol, struct replay_opts *opts)
 724 {
 725         unsigned char commit_sha1[20];
 726         enum replay_action action;
 727         char *end_of_object_name;
 728         int saved, status, padding;
 729
 730         if (starts_with(bol, "pick")) {
 731                 action = REPLAY_PICK;
 732                 bol += strlen("pick");
 733         } else if (starts_with(bol, "revert")) {
 734                 action = REPLAY_REVERT;
 735                 bol += strlen("revert");
 736         } else
 737                 return NULL;
 738
 739         /* Eat up extra spaces/ tabs before object name */
 740         padding = strspn(bol, " \t");
 741         if (!padding)
 742                 return NULL;
 743         bol += padding;
 744
 745         end_of_object_name = bol + strcspn(bol, " \t\n");
 746         saved = *end_of_object_name;
 747         *end_of_object_name = '\0';
 748         status = get_sha1(bol, commit_sha1);
 749         *end_of_object_name = saved;
 750
 751         /*
 752          * Verify that the action matches up with the one in
 753          * opts; we don't support arbitrary instructions
 754          */
 755         if (action != opts->action) {
 756                 const char *action_str;
 757                 action_str = action == REPLAY_REVERT ? "revert" : "cherry-pick";
 758                 error(_("Cannot %s during a %s"), action_str, action_name(opts));
 759                 return NULL;
 760         }
 761
 762         if (status < 0)
 763                 return NULL;
 764
 765         return lookup_commit_reference(commit_sha1);
 766 }
 767
 768 static int parse_insn_buffer(char *buf, struct commit_list **todo_list,
 769                         struct replay_opts *opts)
 770 {
 771         struct commit_list **next = todo_list;
 772         struct commit *commit;
 773         char *p = buf;
 774         int i;
 775
 776         for (i = 1; *p; i++) {
 777                 char *eol = strchrnul(p, '\n');
 778                 commit = parse_insn_line(p, eol, opts);
 779                 if (!commit)
 780                         return error(_("Could not parse line %d."), i);
 781                 next = commit_list_append(commit, next);
 782                 p = *eol ? eol + 1 : eol;
 783         }
 784         if (!*todo_list)
 785                 return error(_("No commits parsed."));
 786         return 0;
 787 }
 788
 789 static void read_populate_todo(struct commit_list **todo_list,
 790                         struct replay_opts *opts)
 791 {
 792         const char *todo_file = git_path(SEQ_TODO_FILE);
 793         struct strbuf buf = STRBUF_INIT;
 794         int fd, res;
 795
 796         fd = open(todo_file, O_RDONLY);
 797         if (fd < 0)
 798                 die_errno(_("Could not open %s"), todo_file);
 799         if (strbuf_read(&buf, fd, 0) < 0) {
 800                 close(fd);
 801                 strbuf_release(&buf);
 802                 die(_("Could not read %s."), todo_file);
 803         }
 804         close(fd);
 805
 806         res = parse_insn_buffer(buf.buf, todo_list, opts);
 807         strbuf_release(&buf);
 808         if (res)
 809                 die(_("Unusable instruction sheet: %s"), todo_file);
 810 }
 811
 812 static int populate_opts_cb(const char *key, const char *value, void *data)
 813 {
 814         struct replay_opts *opts = data;
 815         int error_flag = 1;
 816
 817         if (!value)
 818                 error_flag = 0;
 819         else if (!strcmp(key, "options.no-commit"))
 820                 opts->no_commit = git_config_bool_or_int(key, value, &error_flag);
 821         else if (!strcmp(key, "options.edit"))
 822                 opts->edit = git_config_bool_or_int(key, value, &error_flag);
 823         else if (!strcmp(key, "options.signoff"))
 824                 opts->signoff = git_config_bool_or_int(key, value, &error_flag);
 825         else if (!strcmp(key, "options.record-origin"))
 826                 opts->record_origin = git_config_bool_or_int(key, value, &error_flag);
 827         else if (!strcmp(key, "options.allow-ff"))
 828                 opts->allow_ff = git_config_bool_or_int(key, value, &error_flag);
 829         else if (!strcmp(key, "options.mainline"))
 830                 opts->mainline = git_config_int(key, value);
 831         else if (!strcmp(key, "options.strategy"))
 832                 git_config_string(&opts->strategy, key, value);
 833         else if (!strcmp(key, "options.gpg-sign"))
 834                 git_config_string(&opts->gpg_sign, key, value);
 835         else if (!strcmp(key, "options.strategy-option")) {
 836                 ALLOC_GROW(opts->xopts, opts->xopts_nr + 1, opts->xopts_alloc);
 837                 opts->xopts[opts->xopts_nr++] = xstrdup(value);
 838         } else if (!strcmp(key, "options.allow-rerere-auto"))
 839                 opts->allow_rerere_auto = git_config_int(key, value);
 840         else if (!strcmp(key, "options.action-name"))
 841                 git_config_string(&opts->action_name, key, value);
 842         else
 843                 return error(_("Invalid key: %s"), key);
 844
 845         if (!error_flag)
 846                 return error(_("Invalid value for %s: %s"), key, value);
 847
 848         return 0;
 849 }
 850
 851 static void read_populate_opts(struct replay_opts **opts_ptr)
 852 {
 853         const char *opts_file = git_path(SEQ_OPTS_FILE);
 854
 855         if (!file_exists(opts_file))
 856                 return;
 857         if (git_config_from_file(populate_opts_cb, opts_file, *opts_ptr) < 0)
 858                 die(_("Malformed options sheet: %s"), opts_file);
 859 }
 860
 861 static void walk_revs_populate_todo(struct commit_list **todo_list,
 862                                 struct replay_opts *opts)
 863 {
 864         struct commit *commit;
 865         struct commit_list **next;
 866
 867         prepare_revs(opts);
 868
 869         next = todo_list;
 870         while ((commit = get_revision(opts->revs)))
 871                 next = commit_list_append(commit, next);
 872 }
 873
 874 static int create_seq_dir(void)
 875 {
 876         const char *seq_dir = git_path(SEQ_DIR);
 877
 878         if (file_exists(seq_dir)) {
 879                 error(_("a cherry-pick or revert is already in progress"));
 880                 advise(_("try \"git cherry-pick (--continue | --quit | --abort)\""));
 881                 return -1;
 882         }
 883         else if (mkdir(seq_dir, 0777) < 0)
 884                 die_errno(_("Could not create sequencer directory %s"), seq_dir);
 885         return 0;
 886 }
 887
 888 static void save_head(const char *head)
 889 {
 890         const char *head_file = git_path(SEQ_HEAD_FILE);
 891         static struct lock_file head_lock;
 892         struct strbuf buf = STRBUF_INIT;
 893         int fd;
 894
 895         fd = hold_lock_file_for_update(&head_lock, head_file, LOCK_DIE_ON_ERROR);
 896         strbuf_addf(&buf, "%s\n", head);
 897         if (write_in_full(fd, buf.buf, buf.len) < 0)
 898                 die_errno(_("Could not write to %s"), head_file);
 899         if (commit_lock_file(&head_lock) < 0)
 900                 die(_("Error wrapping up %s."), head_file);
 901 }
 902
 903 static int reset_for_rollback(const unsigned char *sha1)
 904 {
 905         const char *argv[4];    /* reset --merge <arg> + NULL */
 906         argv[0] = "reset";
 907         argv[1] = "--merge";
 908         argv[2] = sha1_to_hex(sha1);
 909         argv[3] = NULL;
 910         return run_command_v_opt(argv, RUN_GIT_CMD);
 911 }
 912
 913 static int rollback_single_pick(void)
 914 {
 915         unsigned char head_sha1[20];
 916
 917         if (!file_exists(git_path("CHERRY_PICK_HEAD")) &&
 918             !file_exists(git_path("REVERT_HEAD")))
 919                 return error(_("no cherry-pick or revert in progress"));
 920         if (read_ref_full("HEAD", 0, head_sha1, NULL))
 921                 return error(_("cannot resolve HEAD"));
 922         if (is_null_sha1(head_sha1))
 923                 return error(_("cannot abort from a branch yet to be born"));
 924         return reset_for_rollback(head_sha1);
 925 }
 926
 927 static int sequencer_rollback(struct replay_opts *opts)
 928 {
 929         const char *filename;
 930         FILE *f;
 931         unsigned char sha1[20];
 932         struct strbuf buf = STRBUF_INIT;
 933         struct string_list merge_rr = STRING_LIST_INIT_DUP;
 934
 935         if (setup_rerere(&merge_rr, 0) >= 0) {
 936                 rerere_clear(&merge_rr);
 937                 string_list_clear(&merge_rr, 1);
 938         }
 939
 940         filename = git_path(SEQ_HEAD_FILE);
 941         f = fopen(filename, "r");
 942         if (!f && errno == ENOENT) {
 943                 /*
 944                  * There is no multiple-cherry-pick in progress.
 945                  * If CHERRY_PICK_HEAD or REVERT_HEAD indicates
 946                  * a single-cherry-pick in progress, abort that.
 947                  */
 948                 return rollback_single_pick();
 949         }
 950         if (!f)
 951                 return error(_("cannot open %s: %s"), filename,
 952                                                 strerror(errno));
 953         if (strbuf_getline(&buf, f, '\n')) {
 954                 error(_("cannot read %s: %s"), filename, ferror(f) ?
 955                         strerror(errno) : _("unexpected end of file"));
 956                 fclose(f);
 957                 goto fail;
 958         }
 959         fclose(f);
 960         if (get_sha1_hex(buf.buf, sha1) || buf.buf[40] != '\0') {
 961                 error(_("stored pre-cherry-pick HEAD file '%s' is corrupt"),
 962                         filename);
 963                 goto fail;
 964         }
 965         if (reset_for_rollback(sha1))
 966                 goto fail;
 967         remove_sequencer_state();
 968         strbuf_release(&buf);
 969         return 0;
 970 fail:
 971         strbuf_release(&buf);
 972         return -1;
 973 }
 974
 975 static void save_todo(struct commit_list *todo_list, struct replay_opts *opts)
 976 {
 977         const char *todo_file = git_path(SEQ_TODO_FILE);
 978         static struct lock_file todo_lock;
 979         struct strbuf buf = STRBUF_INIT;
 980         int fd;
 981
 982         fd = hold_lock_file_for_update(&todo_lock, todo_file, LOCK_DIE_ON_ERROR);
 983         if (format_todo(&buf, todo_list, opts) < 0)
 984                 die(_("Could not format %s."), todo_file);
 985         if (write_in_full(fd, buf.buf, buf.len) < 0) {
 986                 strbuf_release(&buf);
 987                 die_errno(_("Could not write to %s"), todo_file);
 988         }
 989         if (commit_lock_file(&todo_lock) < 0) {
 990                 strbuf_release(&buf);
 991                 die(_("Error wrapping up %s."), todo_file);
 992         }
 993         strbuf_release(&buf);
 994 }
 995
 996 static void save_opts(struct replay_opts *opts)
 997 {
 998         const char *opts_file = git_path(SEQ_OPTS_FILE);
 999
1000         if (opts->no_commit)
1001                 git_config_set_in_file(opts_file, "options.no-commit", "true");
1002         if (opts->edit)
1003                 git_config_set_in_file(opts_file, "options.edit", "true");
1004         if (opts->signoff)
1005                 git_config_set_in_file(opts_file, "options.signoff", "true");
1006         if (opts->record_origin)
1007                 git_config_set_in_file(opts_file, "options.record-origin", "true");
1008         if (opts->allow_ff)
1009                 git_config_set_in_file(opts_file, "options.allow-ff", "true");
1010         if (opts->mainline) {
1011                 struct strbuf buf = STRBUF_INIT;
1012                 strbuf_addf(&buf, "%d", opts->mainline);
1013                 git_config_set_in_file(opts_file, "options.mainline", buf.buf);
1014                 strbuf_release(&buf);
1015         }
1016         if (opts->strategy)
1017                 git_config_set_in_file(opts_file, "options.strategy", opts->strategy);
1018         if (opts->gpg_sign)
1019                 git_config_set_in_file(opts_file, "options.gpg-sign", opts->gpg_sign);
1020         if (opts->xopts) {
1021                 int i;
1022                 for (i = 0; i < opts->xopts_nr; i++)
1023                         git_config_set_multivar_in_file(opts_file,
1024                                                         "options.strategy-option",
1025                                                         opts->xopts[i], "^$", 0);
1026         }
1027         if (opts->allow_rerere_auto) {
1028                 struct strbuf buf = STRBUF_INIT;
1029                 strbuf_addf(&buf, "%d", opts->allow_rerere_auto);
1030                 git_config_set_in_file(opts_file, "options.allow-rerere-auto", buf.buf);
1031                 strbuf_release(&buf);
1032         }
1033         if (opts->action_name)
1034                 git_config_set_in_file(opts_file, "options.action-name", opts->action_name);
1035 }
1036
1037 static int pick_commits(struct commit_list *todo_list, struct replay_opts *opts)
1038 {
1039         struct commit_list *cur;
1040         int res;
1041
1042         setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
1043         if (opts->allow_ff)
1044                 assert(!(opts->signoff || opts->no_commit ||
1045                                 opts->record_origin || opts->edit));
1046         read_and_refresh_cache(opts);
1047
1048         for (cur = todo_list; cur; cur = cur->next) {
1049                 save_todo(cur, opts);
1050                 res = do_pick_commit(cur->item, opts);
1051                 if (res) {
1052                         if (opts->action == REPLAY_PICK)
1053                                 store_rewritten(&rewritten, git_path(SEQ_REWR_FILE));
1054                         return res;
1055                 }
1056         }
1057
1058         finish(opts);
1059
1060         /*
1061          * Sequence of picks finished successfully; cleanup by
1062          * removing the .git/sequencer directory
1063          */
1064         remove_sequencer_state();
1065         return 0;
1066 }
1067
1068 static int continue_single_pick(void)
1069 {
1070         const char *argv[] = { "commit", NULL };
1071
1072         if (!file_exists(git_path("CHERRY_PICK_HEAD")) &&
1073             !file_exists(git_path("REVERT_HEAD")))
1074                 return error(_("no cherry-pick or revert in progress"));
1075         return run_command_v_opt(argv, RUN_GIT_CMD);
1076 }
1077
1078 static int sequencer_continue(struct replay_opts *opts, int skip)
1079 {
1080         struct commit_list *todo_list = NULL;
1081
1082         if (!file_exists(git_path(SEQ_TODO_FILE)))
1083                 return continue_single_pick();
1084         read_populate_opts(&opts);
1085         read_populate_todo(&todo_list, opts);
1086         if (opts->action == REPLAY_PICK)
1087                 load_rewritten(&rewritten, git_path(SEQ_REWR_FILE));
1088
1089         /* Verify that the conflict has been resolved */
1090         if (file_exists(git_path("CHERRY_PICK_HEAD")) ||
1091             file_exists(git_path("REVERT_HEAD"))) {
1092                 int ret = continue_single_pick();
1093                 if (ret)
1094                         return ret;
1095         }
1096         if (index_differs_from("HEAD", 0))
1097                 return error_dirty_index(opts);
1098         if (opts->action == REPLAY_PICK && !skip) {
1099                 unsigned char to[20];
1100                 if (!read_ref("HEAD", to))
1101                         add_rewritten(&rewritten, todo_list->item->object.sha1, to);
1102         }
1103         todo_list = todo_list->next;
1104         return pick_commits(todo_list, opts);
1105 }
1106
1107 static int sequencer_skip(struct replay_opts *opts)
1108 {
1109         const char *argv[3]; /* reset --hard + NULL */
1110         struct string_list merge_rr = STRING_LIST_INIT_DUP;
1111         int ret;
1112
1113         if (setup_rerere(&merge_rr, 0) >= 0) {
1114                 rerere_clear(&merge_rr);
1115                 string_list_clear(&merge_rr, 1);
1116         }
1117
1118         argv[0] = "reset";
1119         argv[1] = "--hard";
1120         argv[2] = NULL;
1121         ret = run_command_v_opt(argv, RUN_GIT_CMD);
1122         if (ret)
1123                 return ret;
1124
1125         discard_cache();
1126         read_cache();
1127
1128         return sequencer_continue(opts, 1);
1129 }
1130
1131 static int single_pick(struct commit *cmit, struct replay_opts *opts)
1132 {
1133         int ret;
1134         setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
1135         ret = do_pick_commit(cmit, opts);
1136         if (ret)
1137                 return ret;
1138         finish(opts);
1139         return 0;
1140 }
1141
1142 int sequencer_pick_revisions(struct replay_opts *opts)
1143 {
1144         struct commit_list *todo_list = NULL;
1145         unsigned char sha1[20];
1146         int i;
1147
1148         if (opts->subcommand == REPLAY_NONE)
1149                 assert(opts->revs);
1150
1151         read_and_refresh_cache(opts);
1152
1153         /*
1154          * Decide what to do depending on the arguments; a fresh
1155          * cherry-pick should be handled differently from an existing
1156          * one that is being continued
1157          */
1158         if (opts->subcommand == REPLAY_REMOVE_STATE) {
1159                 remove_sequencer_state();
1160                 return 0;
1161         }
1162         if (opts->subcommand == REPLAY_ROLLBACK)
1163                 return sequencer_rollback(opts);
1164         if (opts->subcommand == REPLAY_CONTINUE)
1165                 return sequencer_continue(opts, 0);
1166         if (opts->subcommand == REPLAY_SKIP)
1167                 return sequencer_skip(opts);
1168
1169         for (i = 0; i < opts->revs->pending.nr; i++) {
1170                 unsigned char sha1[20];
1171                 const char *name = opts->revs->pending.objects[i].name;
1172
1173                 /* This happens when using --stdin. */
1174                 if (!strlen(name))
1175                         continue;
1176
1177                 if (!get_sha1(name, sha1)) {
1178                         if (!lookup_commit_reference_gently(sha1, 1)) {
1179                                 enum object_type type = sha1_object_info(sha1, NULL);
1180                                 die(_("%s: can't cherry-pick a %s"), name, typename(type));
1181                         }
1182                 } else
1183                         die(_("%s: bad revision"), name);
1184         }
1185
1186         /*
1187          * If we were called as "git cherry-pick <commit>", just
1188          * cherry-pick/revert it, set CHERRY_PICK_HEAD /
1189          * REVERT_HEAD, and don't touch the sequencer state.
1190          * This means it is possible to cherry-pick in the middle
1191          * of a cherry-pick sequence.
1192          */
1193         if (opts->revs->cmdline.nr == 1 &&
1194             opts->revs->cmdline.rev->whence == REV_CMD_REV &&
1195             opts->revs->no_walk &&
1196             !opts->revs->cmdline.rev->flags) {
1197                 struct commit *cmit;
1198                 if (prepare_revision_walk(opts->revs))
1199                         die(_("revision walk setup failed"));
1200                 cmit = get_revision(opts->revs);
1201                 if (!cmit || get_revision(opts->revs))
1202                         die("BUG: expected exactly one commit from walk");
1203                 return single_pick(cmit, opts);
1204         }
1205
1206         /*
1207          * Start a new cherry-pick/ revert sequence; but
1208          * first, make sure that an existing one isn't in
1209          * progress
1210          */
1211
1212         walk_revs_populate_todo(&todo_list, opts);
1213         if (create_seq_dir() < 0)
1214                 return -1;
1215         if (get_sha1("HEAD", sha1)) {
1216                 if (opts->action == REPLAY_REVERT)
1217                         return error(_("Can't revert as initial commit"));
1218                 return error(_("Can't cherry-pick into empty head"));
1219         }
1220         save_head(sha1_to_hex(sha1));
1221         save_opts(opts);
1222         return pick_commits(todo_list, opts);
1223 }
1224
1225 void append_signoff(struct strbuf *msgbuf, int ignore_footer, unsigned flag)
1226 {
1227         unsigned no_dup_sob = flag & APPEND_SIGNOFF_DEDUP;
1228         struct strbuf sob = STRBUF_INIT;
1229         int has_footer;
1230
1231         strbuf_addstr(&sob, sign_off_header);
1232         strbuf_addstr(&sob, fmt_name(getenv("GIT_COMMITTER_NAME"),
1233                                 getenv("GIT_COMMITTER_EMAIL")));
1234         strbuf_addch(&sob, '\n');
1235
1236         /*
1237          * If the whole message buffer is equal to the sob, pretend that we
1238          * found a conforming footer with a matching sob
1239          */
1240         if (msgbuf->len - ignore_footer == sob.len &&
1241             !strncmp(msgbuf->buf, sob.buf, sob.len))
1242                 has_footer = 3;
1243         else
1244                 has_footer = has_conforming_footer(msgbuf, &sob, ignore_footer);
1245
1246         if (!has_footer) {
1247                 const char *append_newlines = NULL;
1248                 size_t len = msgbuf->len - ignore_footer;
1249
1250                 if (!len) {
1251                         /*
1252                          * The buffer is completely empty.  Leave foom for
1253                          * the title and body to be filled in by the user.
1254                          */
1255                         append_newlines = "\n\n";
1256                 } else if (msgbuf->buf[len - 1] != '\n') {
1257                         /*
1258                          * Incomplete line.  Complete the line and add a
1259                          * blank one so that there is an empty line between
1260                          * the message body and the sob.
1261                          */
1262                         append_newlines = "\n\n";
1263                 } else if (len == 1) {
1264                         /*
1265                          * Buffer contains a single newline.  Add another
1266                          * so that we leave room for the title and body.
1267                          */
1268                         append_newlines = "\n";
1269                 } else if (msgbuf->buf[len - 2] != '\n') {
1270                         /*
1271                          * Buffer ends with a single newline.  Add another
1272                          * so that there is an empty line between the message
1273                          * body and the sob.
1274                          */
1275                         append_newlines = "\n";
1276                 } /* else, the buffer already ends with two newlines. */
1277
1278                 if (append_newlines)
1279                         strbuf_splice(msgbuf, msgbuf->len - ignore_footer, 0,
1280                                 append_newlines, strlen(append_newlines));
1281         }
1282
1283         if (has_footer != 3 && (!no_dup_sob || has_footer != 2))
1284                 strbuf_splice(msgbuf, msgbuf->len - ignore_footer, 0,
1285                                 sob.buf, sob.len);
1286
1287         strbuf_release(&sob);
1288 }