sequencer.c

   1 #include "cache.h"
   2 #include "sequencer.h"
   3 #include "dir.h"
   4 #include "object.h"
   5 #include "commit.h"
   6 #include "tag.h"
   7 #include "run-command.h"
   8 #include "exec_cmd.h"
   9 #include "utf8.h"
  10 #include "cache-tree.h"
  11 #include "diff.h"
  12 #include "revision.h"
  13 #include "rerere.h"
  14 #include "merge-recursive.h"
  15 #include "refs.h"
  16 #include "argv-array.h"
  17
  18 #define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION"
  19
  20 void remove_sequencer_state(void)
  21 {
  22         struct strbuf seq_dir = STRBUF_INIT;
  23
  24         strbuf_addf(&seq_dir, "%s", git_path(SEQ_DIR));
  25         remove_dir_recursively(&seq_dir, 0);
  26         strbuf_release(&seq_dir);
  27 }
  28
  29 static const char *action_name(const struct replay_opts *opts)
  30 {
  31         return opts->action == REPLAY_REVERT ? "revert" : "cherry-pick";
  32 }
  33
  34 static char *get_encoding(const char *message);
  35
  36 struct commit_message {
  37         char *parent_label;
  38         const char *label;
  39         const char *subject;
  40         char *reencoded_message;
  41         const char *message;
  42 };
  43
  44 static int get_message(struct commit *commit, struct commit_message *out)
  45 {
  46         const char *encoding;
  47         const char *abbrev, *subject;
  48         int abbrev_len, subject_len;
  49         char *q;
  50
  51         if (!commit->buffer)
  52                 return -1;
  53         encoding = get_encoding(commit->buffer);
  54         if (!encoding)
  55                 encoding = "UTF-8";
  56         if (!git_commit_encoding)
  57                 git_commit_encoding = "UTF-8";
  58
  59         out->reencoded_message = NULL;
  60         out->message = commit->buffer;
  61         if (strcmp(encoding, git_commit_encoding))
  62                 out->reencoded_message = reencode_string(commit->buffer,
  63                                         git_commit_encoding, encoding);
  64         if (out->reencoded_message)
  65                 out->message = out->reencoded_message;
  66
  67         abbrev = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV);
  68         abbrev_len = strlen(abbrev);
  69
  70         subject_len = find_commit_subject(out->message, &subject);
  71
  72         out->parent_label = xmalloc(strlen("parent of ") + abbrev_len +
  73                               strlen("... ") + subject_len + 1);
  74         q = out->parent_label;
  75         q = mempcpy(q, "parent of ", strlen("parent of "));
  76         out->label = q;
  77         q = mempcpy(q, abbrev, abbrev_len);
  78         q = mempcpy(q, "... ", strlen("... "));
  79         out->subject = q;
  80         q = mempcpy(q, subject, subject_len);
  81         *q = '\0';
  82         return 0;
  83 }
  84
  85 static void free_message(struct commit_message *msg)
  86 {
  87         free(msg->parent_label);
  88         free(msg->reencoded_message);
  89 }
  90
  91 static char *get_encoding(const char *message)
  92 {
  93         const char *p = message, *eol;
  94
  95         while (*p && *p != '\n') {
  96                 for (eol = p + 1; *eol && *eol != '\n'; eol++)
  97                         ; /* do nothing */
  98                 if (!prefixcmp(p, "encoding ")) {
  99                         char *result = xmalloc(eol - 8 - p);
 100                         strlcpy(result, p + 9, eol - 8 - p);
 101                         return result;
 102                 }
 103                 p = eol;
 104                 if (*p == '\n')
 105                         p++;
 106         }
 107         return NULL;
 108 }
 109
 110 static void write_cherry_pick_head(struct commit *commit, const char *pseudoref)
 111 {
 112         const char *filename;
 113         int fd;
 114         struct strbuf buf = STRBUF_INIT;
 115
 116         strbuf_addf(&buf, "%s\n", sha1_to_hex(commit->object.sha1));
 117
 118         filename = git_path("%s", pseudoref);
 119         fd = open(filename, O_WRONLY | O_CREAT, 0666);
 120         if (fd < 0)
 121                 die_errno(_("Could not open '%s' for writing"), filename);
 122         if (write_in_full(fd, buf.buf, buf.len) != buf.len || close(fd))
 123                 die_errno(_("Could not write to '%s'"), filename);
 124         strbuf_release(&buf);
 125 }
 126
 127 static void print_advice(int show_hint, struct replay_opts *opts)
 128 {
 129         char *msg = getenv("GIT_CHERRY_PICK_HELP");
 130
 131         if (msg) {
 132                 fprintf(stderr, "%s\n", msg);
 133                 /*
 134                  * A conflict has occured but the porcelain
 135                  * (typically rebase --interactive) wants to take care
 136                  * of the commit itself so remove CHERRY_PICK_HEAD
 137                  */
 138                 unlink(git_path("CHERRY_PICK_HEAD"));
 139                 return;
 140         }
 141
 142         if (show_hint) {
 143                 if (opts->no_commit)
 144                         advise(_("after resolving the conflicts, mark the corrected paths\n"
 145                                  "with 'git add <paths>' or 'git rm <paths>'"));
 146                 else
 147                         advise(_("after resolving the conflicts, mark the corrected paths\n"
 148                                  "with 'git add <paths>' or 'git rm <paths>'\n"
 149                                  "and commit the result with 'git commit'"));
 150         }
 151 }
 152
 153 static void write_message(struct strbuf *msgbuf, const char *filename)
 154 {
 155         static struct lock_file msg_file;
 156
 157         int msg_fd = hold_lock_file_for_update(&msg_file, filename,
 158                                                LOCK_DIE_ON_ERROR);
 159         if (write_in_full(msg_fd, msgbuf->buf, msgbuf->len) < 0)
 160                 die_errno(_("Could not write to %s"), filename);
 161         strbuf_release(msgbuf);
 162         if (commit_lock_file(&msg_file) < 0)
 163                 die(_("Error wrapping up %s"), filename);
 164 }
 165
 166 static struct tree *empty_tree(void)
 167 {
 168         return lookup_tree(EMPTY_TREE_SHA1_BIN);
 169 }
 170
 171 static int error_dirty_index(struct replay_opts *opts)
 172 {
 173         if (read_cache_unmerged())
 174                 return error_resolve_conflict(action_name(opts));
 175
 176         /* Different translation strings for cherry-pick and revert */
 177         if (opts->action == REPLAY_PICK)
 178                 error(_("Your local changes would be overwritten by cherry-pick."));
 179         else
 180                 error(_("Your local changes would be overwritten by revert."));
 181
 182         if (advice_commit_before_merge)
 183                 advise(_("Commit your changes or stash them to proceed."));
 184         return -1;
 185 }
 186
 187 static int fast_forward_to(const unsigned char *to, const unsigned char *from)
 188 {
 189         struct ref_lock *ref_lock;
 190
 191         read_cache();
 192         if (checkout_fast_forward(from, to))
 193                 exit(1); /* the callee should have complained already */
 194         ref_lock = lock_any_ref_for_update("HEAD", from, 0);
 195         return write_ref_sha1(ref_lock, to, "cherry-pick");
 196 }
 197
 198 static int do_recursive_merge(struct commit *base, struct commit *next,
 199                               const char *base_label, const char *next_label,
 200                               unsigned char *head, struct strbuf *msgbuf,
 201                               struct replay_opts *opts)
 202 {
 203         struct merge_options o;
 204         struct tree *result, *next_tree, *base_tree, *head_tree;
 205         int clean, index_fd;
 206         const char **xopt;
 207         static struct lock_file index_lock;
 208
 209         index_fd = hold_locked_index(&index_lock, 1);
 210
 211         read_cache();
 212
 213         init_merge_options(&o);
 214         o.ancestor = base ? base_label : "(empty tree)";
 215         o.branch1 = "HEAD";
 216         o.branch2 = next ? next_label : "(empty tree)";
 217
 218         head_tree = parse_tree_indirect(head);
 219         next_tree = next ? next->tree : empty_tree();
 220         base_tree = base ? base->tree : empty_tree();
 221
 222         for (xopt = opts->xopts; xopt != opts->xopts + opts->xopts_nr; xopt++)
 223                 parse_merge_opt(&o, *xopt);
 224
 225         clean = merge_trees(&o,
 226                             head_tree,
 227                             next_tree, base_tree, &result);
 228
 229         if (active_cache_changed &&
 230             (write_cache(index_fd, active_cache, active_nr) ||
 231              commit_locked_index(&index_lock)))
 232                 /* TRANSLATORS: %s will be "revert" or "cherry-pick" */
 233                 die(_("%s: Unable to write new index file"), action_name(opts));
 234         rollback_lock_file(&index_lock);
 235
 236         if (!clean) {
 237                 int i;
 238                 strbuf_addstr(msgbuf, "\nConflicts:\n");
 239                 for (i = 0; i < active_nr;) {
 240                         struct cache_entry *ce = active_cache[i++];
 241                         if (ce_stage(ce)) {
 242                                 strbuf_addch(msgbuf, '\t');
 243                                 strbuf_addstr(msgbuf, ce->name);
 244                                 strbuf_addch(msgbuf, '\n');
 245                                 while (i < active_nr && !strcmp(ce->name,
 246                                                 active_cache[i]->name))
 247                                         i++;
 248                         }
 249                 }
 250         }
 251
 252         return !clean;
 253 }
 254
 255 static int is_index_unchanged(void)
 256 {
 257         unsigned char head_sha1[20];
 258         struct commit *head_commit;
 259
 260         if (!resolve_ref_unsafe("HEAD", head_sha1, 1, NULL))
 261                 return error(_("Could not resolve HEAD commit\n"));
 262
 263         head_commit = lookup_commit(head_sha1);
 264         if (!head_commit || parse_commit(head_commit))
 265                 return error(_("could not parse commit %s\n"),
 266                              sha1_to_hex(head_commit->object.sha1));
 267
 268         if (!active_cache_tree)
 269                 active_cache_tree = cache_tree();
 270
 271         if (!cache_tree_fully_valid(active_cache_tree))
 272                 if (cache_tree_update(active_cache_tree, active_cache,
 273                                   active_nr, 0))
 274                         return error(_("Unable to update cache tree\n"));
 275
 276         return !hashcmp(active_cache_tree->sha1, head_commit->tree->object.sha1);
 277 }
 278
 279 /*
 280  * If we are cherry-pick, and if the merge did not result in
 281  * hand-editing, we will hit this commit and inherit the original
 282  * author date and name.
 283  * If we are revert, or if our cherry-pick results in a hand merge,
 284  * we had better say that the current user is responsible for that.
 285  */
 286 static int run_git_commit(const char *defmsg, struct replay_opts *opts)
 287 {
 288         struct argv_array array;
 289         int rc;
 290
 291         argv_array_init(&array);
 292         argv_array_push(&array, "commit");
 293         argv_array_push(&array, "-n");
 294
 295         if (opts->signoff)
 296                 argv_array_push(&array, "-s");
 297         if (!opts->edit) {
 298                 argv_array_push(&array, "-F");
 299                 argv_array_push(&array, defmsg);
 300         }
 301
 302         if (opts->allow_empty)
 303                 argv_array_push(&array, "--allow-empty");
 304
 305         rc = run_command_v_opt(array.argv, RUN_GIT_CMD);
 306         argv_array_clear(&array);
 307         return rc;
 308 }
 309
 310 static int is_original_commit_empty(struct commit *commit)
 311 {
 312         const unsigned char *ptree_sha1;
 313
 314         if (parse_commit(commit))
 315                 return error(_("Could not parse commit %s\n"),
 316                              sha1_to_hex(commit->object.sha1));
 317         if (commit->parents) {
 318                 struct commit *parent = commit->parents->item;
 319                 if (parse_commit(parent))
 320                         return error(_("Could not parse parent commit %s\n"),
 321                                 sha1_to_hex(parent->object.sha1));
 322                 ptree_sha1 = parent->tree->object.sha1;
 323         } else {
 324                 ptree_sha1 = EMPTY_TREE_SHA1_BIN; /* commit is root */
 325         }
 326
 327         return !hashcmp(ptree_sha1, commit->tree->object.sha1);
 328 }
 329
 330 static int do_pick_commit(struct commit *commit, struct replay_opts *opts)
 331 {
 332         unsigned char head[20];
 333         struct commit *base, *next, *parent;
 334         const char *base_label, *next_label;
 335         struct commit_message msg = { NULL, NULL, NULL, NULL, NULL };
 336         char *defmsg = NULL;
 337         struct strbuf msgbuf = STRBUF_INIT;
 338         int res;
 339         int empty_commit;
 340         int index_unchanged;
 341
 342         if (opts->no_commit) {
 343                 /*
 344                  * We do not intend to commit immediately.  We just want to
 345                  * merge the differences in, so let's compute the tree
 346                  * that represents the "current" state for merge-recursive
 347                  * to work on.
 348                  */
 349                 if (write_cache_as_tree(head, 0, NULL))
 350                         die (_("Your index file is unmerged."));
 351         } else {
 352                 if (get_sha1("HEAD", head))
 353                         return error(_("You do not have a valid HEAD"));
 354                 if (index_differs_from("HEAD", 0))
 355                         return error_dirty_index(opts);
 356         }
 357         discard_cache();
 358
 359         if (!commit->parents) {
 360                 parent = NULL;
 361         }
 362         else if (commit->parents->next) {
 363                 /* Reverting or cherry-picking a merge commit */
 364                 int cnt;
 365                 struct commit_list *p;
 366
 367                 if (!opts->mainline)
 368                         return error(_("Commit %s is a merge but no -m option was given."),
 369                                 sha1_to_hex(commit->object.sha1));
 370
 371                 for (cnt = 1, p = commit->parents;
 372                      cnt != opts->mainline && p;
 373                      cnt++)
 374                         p = p->next;
 375                 if (cnt != opts->mainline || !p)
 376                         return error(_("Commit %s does not have parent %d"),
 377                                 sha1_to_hex(commit->object.sha1), opts->mainline);
 378                 parent = p->item;
 379         } else if (0 < opts->mainline)
 380                 return error(_("Mainline was specified but commit %s is not a merge."),
 381                         sha1_to_hex(commit->object.sha1));
 382         else
 383                 parent = commit->parents->item;
 384
 385         if (opts->allow_ff && parent && !hashcmp(parent->object.sha1, head))
 386                 return fast_forward_to(commit->object.sha1, head);
 387
 388         if (parent && parse_commit(parent) < 0)
 389                 /* TRANSLATORS: The first %s will be "revert" or
 390                    "cherry-pick", the second %s a SHA1 */
 391                 return error(_("%s: cannot parse parent commit %s"),
 392                         action_name(opts), sha1_to_hex(parent->object.sha1));
 393
 394         if (get_message(commit, &msg) != 0)
 395                 return error(_("Cannot get commit message for %s"),
 396                         sha1_to_hex(commit->object.sha1));
 397
 398         /*
 399          * "commit" is an existing commit.  We would want to apply
 400          * the difference it introduces since its first parent "prev"
 401          * on top of the current HEAD if we are cherry-pick.  Or the
 402          * reverse of it if we are revert.
 403          */
 404
 405         defmsg = git_pathdup("MERGE_MSG");
 406
 407         if (opts->action == REPLAY_REVERT) {
 408                 base = commit;
 409                 base_label = msg.label;
 410                 next = parent;
 411                 next_label = msg.parent_label;
 412                 strbuf_addstr(&msgbuf, "Revert \"");
 413                 strbuf_addstr(&msgbuf, msg.subject);
 414                 strbuf_addstr(&msgbuf, "\"\n\nThis reverts commit ");
 415                 strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));
 416
 417                 if (commit->parents && commit->parents->next) {
 418                         strbuf_addstr(&msgbuf, ", reversing\nchanges made to ");
 419                         strbuf_addstr(&msgbuf, sha1_to_hex(parent->object.sha1));
 420                 }
 421                 strbuf_addstr(&msgbuf, ".\n");
 422         } else {
 423                 const char *p;
 424
 425                 base = parent;
 426                 base_label = msg.parent_label;
 427                 next = commit;
 428                 next_label = msg.label;
 429
 430                 /*
 431                  * Append the commit log message to msgbuf; it starts
 432                  * after the tree, parent, author, committer
 433                  * information followed by "\n\n".
 434                  */
 435                 p = strstr(msg.message, "\n\n");
 436                 if (p) {
 437                         p += 2;
 438                         strbuf_addstr(&msgbuf, p);
 439                 }
 440
 441                 if (opts->record_origin) {
 442                         strbuf_addstr(&msgbuf, "(cherry picked from commit ");
 443                         strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));
 444                         strbuf_addstr(&msgbuf, ")\n");
 445                 }
 446         }
 447
 448         if (!opts->strategy || !strcmp(opts->strategy, "recursive") || opts->action == REPLAY_REVERT) {
 449                 res = do_recursive_merge(base, next, base_label, next_label,
 450                                          head, &msgbuf, opts);
 451                 write_message(&msgbuf, defmsg);
 452         } else {
 453                 struct commit_list *common = NULL;
 454                 struct commit_list *remotes = NULL;
 455
 456                 write_message(&msgbuf, defmsg);
 457
 458                 commit_list_insert(base, &common);
 459                 commit_list_insert(next, &remotes);
 460                 res = try_merge_command(opts->strategy, opts->xopts_nr, opts->xopts,
 461                                         common, sha1_to_hex(head), remotes);
 462                 free_commit_list(common);
 463                 free_commit_list(remotes);
 464         }
 465
 466         empty_commit = is_original_commit_empty(commit);
 467         if (empty_commit < 0)
 468                 return empty_commit;
 469
 470         /*
 471          * If the merge was clean or if it failed due to conflict, we write
 472          * CHERRY_PICK_HEAD for the subsequent invocation of commit to use.
 473          * However, if the merge did not even start, then we don't want to
 474          * write it at all.
 475          */
 476         if (opts->action == REPLAY_PICK && !opts->no_commit && (res == 0 || res == 1))
 477                 write_cherry_pick_head(commit, "CHERRY_PICK_HEAD");
 478         if (opts->action == REPLAY_REVERT && ((opts->no_commit && res == 0) || res == 1))
 479                 write_cherry_pick_head(commit, "REVERT_HEAD");
 480
 481         if (res) {
 482                 error(opts->action == REPLAY_REVERT
 483                       ? _("could not revert %s... %s")
 484                       : _("could not apply %s... %s"),
 485                       find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV),
 486                       msg.subject);
 487                 print_advice(res == 1, opts);
 488                 rerere(opts->allow_rerere_auto);
 489         } else {
 490                 index_unchanged = is_index_unchanged();
 491                 /*
 492                  * If index_unchanged is less than 0, that indicates we either
 493                  * couldn't parse HEAD or the index, so error out here.
 494                  */
 495                 if (index_unchanged < 0)
 496                         return index_unchanged;
 497
 498                 if (!empty_commit && !opts->keep_redundant_commits && index_unchanged)
 499                         /*
 500                          * The head tree and the index match
 501                          * meaning the commit is empty.  Since it wasn't created
 502                          * empty (based on the previous test), we can conclude
 503                          * the commit has been made redundant.  Since we don't
 504                          * want to keep redundant commits, we can just return
 505                          * here, skipping this commit
 506                          */
 507                         return 0;
 508
 509                 if (!opts->no_commit)
 510                         res = run_git_commit(defmsg, opts);
 511         }
 512
 513         free_message(&msg);
 514         free(defmsg);
 515
 516         return res;
 517 }
 518
 519 static void prepare_revs(struct replay_opts *opts)
 520 {
 521         if (opts->action != REPLAY_REVERT)
 522                 opts->revs->reverse ^= 1;
 523
 524         if (prepare_revision_walk(opts->revs))
 525                 die(_("revision walk setup failed"));
 526
 527         if (!opts->revs->commits)
 528                 die(_("empty commit set passed"));
 529 }
 530
 531 static void read_and_refresh_cache(struct replay_opts *opts)
 532 {
 533         static struct lock_file index_lock;
 534         int index_fd = hold_locked_index(&index_lock, 0);
 535         if (read_index_preload(&the_index, NULL) < 0)
 536                 die(_("git %s: failed to read the index"), action_name(opts));
 537         refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED, NULL, NULL, NULL);
 538         if (the_index.cache_changed) {
 539                 if (write_index(&the_index, index_fd) ||
 540                     commit_locked_index(&index_lock))
 541                         die(_("git %s: failed to refresh the index"), action_name(opts));
 542         }
 543         rollback_lock_file(&index_lock);
 544 }
 545
 546 static int format_todo(struct strbuf *buf, struct commit_list *todo_list,
 547                 struct replay_opts *opts)
 548 {
 549         struct commit_list *cur = NULL;
 550         const char *sha1_abbrev = NULL;
 551         const char *action_str = opts->action == REPLAY_REVERT ? "revert" : "pick";
 552         const char *subject;
 553         int subject_len;
 554
 555         for (cur = todo_list; cur; cur = cur->next) {
 556                 sha1_abbrev = find_unique_abbrev(cur->item->object.sha1, DEFAULT_ABBREV);
 557                 subject_len = find_commit_subject(cur->item->buffer, &subject);
 558                 strbuf_addf(buf, "%s %s %.*s\n", action_str, sha1_abbrev,
 559                         subject_len, subject);
 560         }
 561         return 0;
 562 }
 563
 564 static struct commit *parse_insn_line(char *bol, char *eol, struct replay_opts *opts)
 565 {
 566         unsigned char commit_sha1[20];
 567         enum replay_action action;
 568         char *end_of_object_name;
 569         int saved, status, padding;
 570
 571         if (!prefixcmp(bol, "pick")) {
 572                 action = REPLAY_PICK;
 573                 bol += strlen("pick");
 574         } else if (!prefixcmp(bol, "revert")) {
 575                 action = REPLAY_REVERT;
 576                 bol += strlen("revert");
 577         } else
 578                 return NULL;
 579
 580         /* Eat up extra spaces/ tabs before object name */
 581         padding = strspn(bol, " \t");
 582         if (!padding)
 583                 return NULL;
 584         bol += padding;
 585
 586         end_of_object_name = bol + strcspn(bol, " \t\n");
 587         saved = *end_of_object_name;
 588         *end_of_object_name = '\0';
 589         status = get_sha1(bol, commit_sha1);
 590         *end_of_object_name = saved;
 591
 592         /*
 593          * Verify that the action matches up with the one in
 594          * opts; we don't support arbitrary instructions
 595          */
 596         if (action != opts->action) {
 597                 const char *action_str;
 598                 action_str = action == REPLAY_REVERT ? "revert" : "cherry-pick";
 599                 error(_("Cannot %s during a %s"), action_str, action_name(opts));
 600                 return NULL;
 601         }
 602
 603         if (status < 0)
 604                 return NULL;
 605
 606         return lookup_commit_reference(commit_sha1);
 607 }
 608
 609 static int parse_insn_buffer(char *buf, struct commit_list **todo_list,
 610                         struct replay_opts *opts)
 611 {
 612         struct commit_list **next = todo_list;
 613         struct commit *commit;
 614         char *p = buf;
 615         int i;
 616
 617         for (i = 1; *p; i++) {
 618                 char *eol = strchrnul(p, '\n');
 619                 commit = parse_insn_line(p, eol, opts);
 620                 if (!commit)
 621                         return error(_("Could not parse line %d."), i);
 622                 next = commit_list_append(commit, next);
 623                 p = *eol ? eol + 1 : eol;
 624         }
 625         if (!*todo_list)
 626                 return error(_("No commits parsed."));
 627         return 0;
 628 }
 629
 630 static void read_populate_todo(struct commit_list **todo_list,
 631                         struct replay_opts *opts)
 632 {
 633         const char *todo_file = git_path(SEQ_TODO_FILE);
 634         struct strbuf buf = STRBUF_INIT;
 635         int fd, res;
 636
 637         fd = open(todo_file, O_RDONLY);
 638         if (fd < 0)
 639                 die_errno(_("Could not open %s"), todo_file);
 640         if (strbuf_read(&buf, fd, 0) < 0) {
 641                 close(fd);
 642                 strbuf_release(&buf);
 643                 die(_("Could not read %s."), todo_file);
 644         }
 645         close(fd);
 646
 647         res = parse_insn_buffer(buf.buf, todo_list, opts);
 648         strbuf_release(&buf);
 649         if (res)
 650                 die(_("Unusable instruction sheet: %s"), todo_file);
 651 }
 652
 653 static int populate_opts_cb(const char *key, const char *value, void *data)
 654 {
 655         struct replay_opts *opts = data;
 656         int error_flag = 1;
 657
 658         if (!value)
 659                 error_flag = 0;
 660         else if (!strcmp(key, "options.no-commit"))
 661                 opts->no_commit = git_config_bool_or_int(key, value, &error_flag);
 662         else if (!strcmp(key, "options.edit"))
 663                 opts->edit = git_config_bool_or_int(key, value, &error_flag);
 664         else if (!strcmp(key, "options.signoff"))
 665                 opts->signoff = git_config_bool_or_int(key, value, &error_flag);
 666         else if (!strcmp(key, "options.record-origin"))
 667                 opts->record_origin = git_config_bool_or_int(key, value, &error_flag);
 668         else if (!strcmp(key, "options.allow-ff"))
 669                 opts->allow_ff = git_config_bool_or_int(key, value, &error_flag);
 670         else if (!strcmp(key, "options.mainline"))
 671                 opts->mainline = git_config_int(key, value);
 672         else if (!strcmp(key, "options.strategy"))
 673                 git_config_string(&opts->strategy, key, value);
 674         else if (!strcmp(key, "options.strategy-option")) {
 675                 ALLOC_GROW(opts->xopts, opts->xopts_nr + 1, opts->xopts_alloc);
 676                 opts->xopts[opts->xopts_nr++] = xstrdup(value);
 677         } else
 678                 return error(_("Invalid key: %s"), key);
 679
 680         if (!error_flag)
 681                 return error(_("Invalid value for %s: %s"), key, value);
 682
 683         return 0;
 684 }
 685
 686 static void read_populate_opts(struct replay_opts **opts_ptr)
 687 {
 688         const char *opts_file = git_path(SEQ_OPTS_FILE);
 689
 690         if (!file_exists(opts_file))
 691                 return;
 692         if (git_config_from_file(populate_opts_cb, opts_file, *opts_ptr) < 0)
 693                 die(_("Malformed options sheet: %s"), opts_file);
 694 }
 695
 696 static void walk_revs_populate_todo(struct commit_list **todo_list,
 697                                 struct replay_opts *opts)
 698 {
 699         struct commit *commit;
 700         struct commit_list **next;
 701
 702         prepare_revs(opts);
 703
 704         next = todo_list;
 705         while ((commit = get_revision(opts->revs)))
 706                 next = commit_list_append(commit, next);
 707 }
 708
 709 static int create_seq_dir(void)
 710 {
 711         const char *seq_dir = git_path(SEQ_DIR);
 712
 713         if (file_exists(seq_dir)) {
 714                 error(_("a cherry-pick or revert is already in progress"));
 715                 advise(_("try \"git cherry-pick (--continue | --quit | --abort)\""));
 716                 return -1;
 717         }
 718         else if (mkdir(seq_dir, 0777) < 0)
 719                 die_errno(_("Could not create sequencer directory %s"), seq_dir);
 720         return 0;
 721 }
 722
 723 static void save_head(const char *head)
 724 {
 725         const char *head_file = git_path(SEQ_HEAD_FILE);
 726         static struct lock_file head_lock;
 727         struct strbuf buf = STRBUF_INIT;
 728         int fd;
 729
 730         fd = hold_lock_file_for_update(&head_lock, head_file, LOCK_DIE_ON_ERROR);
 731         strbuf_addf(&buf, "%s\n", head);
 732         if (write_in_full(fd, buf.buf, buf.len) < 0)
 733                 die_errno(_("Could not write to %s"), head_file);
 734         if (commit_lock_file(&head_lock) < 0)
 735                 die(_("Error wrapping up %s."), head_file);
 736 }
 737
 738 static int reset_for_rollback(const unsigned char *sha1)
 739 {
 740         const char *argv[4];    /* reset --merge <arg> + NULL */
 741         argv[0] = "reset";
 742         argv[1] = "--merge";
 743         argv[2] = sha1_to_hex(sha1);
 744         argv[3] = NULL;
 745         return run_command_v_opt(argv, RUN_GIT_CMD);
 746 }
 747
 748 static int rollback_single_pick(void)
 749 {
 750         unsigned char head_sha1[20];
 751
 752         if (!file_exists(git_path("CHERRY_PICK_HEAD")) &&
 753             !file_exists(git_path("REVERT_HEAD")))
 754                 return error(_("no cherry-pick or revert in progress"));
 755         if (read_ref_full("HEAD", head_sha1, 0, NULL))
 756                 return error(_("cannot resolve HEAD"));
 757         if (is_null_sha1(head_sha1))
 758                 return error(_("cannot abort from a branch yet to be born"));
 759         return reset_for_rollback(head_sha1);
 760 }
 761
 762 static int sequencer_rollback(struct replay_opts *opts)
 763 {
 764         const char *filename;
 765         FILE *f;
 766         unsigned char sha1[20];
 767         struct strbuf buf = STRBUF_INIT;
 768
 769         filename = git_path(SEQ_HEAD_FILE);
 770         f = fopen(filename, "r");
 771         if (!f && errno == ENOENT) {
 772                 /*
 773                  * There is no multiple-cherry-pick in progress.
 774                  * If CHERRY_PICK_HEAD or REVERT_HEAD indicates
 775                  * a single-cherry-pick in progress, abort that.
 776                  */
 777                 return rollback_single_pick();
 778         }
 779         if (!f)
 780                 return error(_("cannot open %s: %s"), filename,
 781                                                 strerror(errno));
 782         if (strbuf_getline(&buf, f, '\n')) {
 783                 error(_("cannot read %s: %s"), filename, ferror(f) ?
 784                         strerror(errno) : _("unexpected end of file"));
 785                 fclose(f);
 786                 goto fail;
 787         }
 788         fclose(f);
 789         if (get_sha1_hex(buf.buf, sha1) || buf.buf[40] != '\0') {
 790                 error(_("stored pre-cherry-pick HEAD file '%s' is corrupt"),
 791                         filename);
 792                 goto fail;
 793         }
 794         if (reset_for_rollback(sha1))
 795                 goto fail;
 796         remove_sequencer_state();
 797         strbuf_release(&buf);
 798         return 0;
 799 fail:
 800         strbuf_release(&buf);
 801         return -1;
 802 }
 803
 804 static void save_todo(struct commit_list *todo_list, struct replay_opts *opts)
 805 {
 806         const char *todo_file = git_path(SEQ_TODO_FILE);
 807         static struct lock_file todo_lock;
 808         struct strbuf buf = STRBUF_INIT;
 809         int fd;
 810
 811         fd = hold_lock_file_for_update(&todo_lock, todo_file, LOCK_DIE_ON_ERROR);
 812         if (format_todo(&buf, todo_list, opts) < 0)
 813                 die(_("Could not format %s."), todo_file);
 814         if (write_in_full(fd, buf.buf, buf.len) < 0) {
 815                 strbuf_release(&buf);
 816                 die_errno(_("Could not write to %s"), todo_file);
 817         }
 818         if (commit_lock_file(&todo_lock) < 0) {
 819                 strbuf_release(&buf);
 820                 die(_("Error wrapping up %s."), todo_file);
 821         }
 822         strbuf_release(&buf);
 823 }
 824
 825 static void save_opts(struct replay_opts *opts)
 826 {
 827         const char *opts_file = git_path(SEQ_OPTS_FILE);
 828
 829         if (opts->no_commit)
 830                 git_config_set_in_file(opts_file, "options.no-commit", "true");
 831         if (opts->edit)
 832                 git_config_set_in_file(opts_file, "options.edit", "true");
 833         if (opts->signoff)
 834                 git_config_set_in_file(opts_file, "options.signoff", "true");
 835         if (opts->record_origin)
 836                 git_config_set_in_file(opts_file, "options.record-origin", "true");
 837         if (opts->allow_ff)
 838                 git_config_set_in_file(opts_file, "options.allow-ff", "true");
 839         if (opts->mainline) {
 840                 struct strbuf buf = STRBUF_INIT;
 841                 strbuf_addf(&buf, "%d", opts->mainline);
 842                 git_config_set_in_file(opts_file, "options.mainline", buf.buf);
 843                 strbuf_release(&buf);
 844         }
 845         if (opts->strategy)
 846                 git_config_set_in_file(opts_file, "options.strategy", opts->strategy);
 847         if (opts->xopts) {
 848                 int i;
 849                 for (i = 0; i < opts->xopts_nr; i++)
 850                         git_config_set_multivar_in_file(opts_file,
 851                                                         "options.strategy-option",
 852                                                         opts->xopts[i], "^$", 0);
 853         }
 854 }
 855
 856 static int pick_commits(struct commit_list *todo_list, struct replay_opts *opts)
 857 {
 858         struct commit_list *cur;
 859         int res;
 860
 861         setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
 862         if (opts->allow_ff)
 863                 assert(!(opts->signoff || opts->no_commit ||
 864                                 opts->record_origin || opts->edit));
 865         read_and_refresh_cache(opts);
 866
 867         for (cur = todo_list; cur; cur = cur->next) {
 868                 save_todo(cur, opts);
 869                 res = do_pick_commit(cur->item, opts);
 870                 if (res)
 871                         return res;
 872         }
 873
 874         /*
 875          * Sequence of picks finished successfully; cleanup by
 876          * removing the .git/sequencer directory
 877          */
 878         remove_sequencer_state();
 879         return 0;
 880 }
 881
 882 static int continue_single_pick(void)
 883 {
 884         const char *argv[] = { "commit", NULL };
 885
 886         if (!file_exists(git_path("CHERRY_PICK_HEAD")) &&
 887             !file_exists(git_path("REVERT_HEAD")))
 888                 return error(_("no cherry-pick or revert in progress"));
 889         return run_command_v_opt(argv, RUN_GIT_CMD);
 890 }
 891
 892 static int sequencer_continue(struct replay_opts *opts)
 893 {
 894         struct commit_list *todo_list = NULL;
 895
 896         if (!file_exists(git_path(SEQ_TODO_FILE)))
 897                 return continue_single_pick();
 898         read_populate_opts(&opts);
 899         read_populate_todo(&todo_list, opts);
 900
 901         /* Verify that the conflict has been resolved */
 902         if (file_exists(git_path("CHERRY_PICK_HEAD")) ||
 903             file_exists(git_path("REVERT_HEAD"))) {
 904                 int ret = continue_single_pick();
 905                 if (ret)
 906                         return ret;
 907         }
 908         if (index_differs_from("HEAD", 0))
 909                 return error_dirty_index(opts);
 910         todo_list = todo_list->next;
 911         return pick_commits(todo_list, opts);
 912 }
 913
 914 static int single_pick(struct commit *cmit, struct replay_opts *opts)
 915 {
 916         setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
 917         return do_pick_commit(cmit, opts);
 918 }
 919
 920 int sequencer_pick_revisions(struct replay_opts *opts)
 921 {
 922         struct commit_list *todo_list = NULL;
 923         unsigned char sha1[20];
 924
 925         if (opts->subcommand == REPLAY_NONE)
 926                 assert(opts->revs);
 927
 928         read_and_refresh_cache(opts);
 929
 930         /*
 931          * Decide what to do depending on the arguments; a fresh
 932          * cherry-pick should be handled differently from an existing
 933          * one that is being continued
 934          */
 935         if (opts->subcommand == REPLAY_REMOVE_STATE) {
 936                 remove_sequencer_state();
 937                 return 0;
 938         }
 939         if (opts->subcommand == REPLAY_ROLLBACK)
 940                 return sequencer_rollback(opts);
 941         if (opts->subcommand == REPLAY_CONTINUE)
 942                 return sequencer_continue(opts);
 943
 944         /*
 945          * If we were called as "git cherry-pick <commit>", just
 946          * cherry-pick/revert it, set CHERRY_PICK_HEAD /
 947          * REVERT_HEAD, and don't touch the sequencer state.
 948          * This means it is possible to cherry-pick in the middle
 949          * of a cherry-pick sequence.
 950          */
 951         if (opts->revs->cmdline.nr == 1 &&
 952             opts->revs->cmdline.rev->whence == REV_CMD_REV &&
 953             opts->revs->no_walk &&
 954             !opts->revs->cmdline.rev->flags) {
 955                 struct commit *cmit;
 956                 if (prepare_revision_walk(opts->revs))
 957                         die(_("revision walk setup failed"));
 958                 cmit = get_revision(opts->revs);
 959                 if (!cmit || get_revision(opts->revs))
 960                         die("BUG: expected exactly one commit from walk");
 961                 return single_pick(cmit, opts);
 962         }
 963
 964         /*
 965          * Start a new cherry-pick/ revert sequence; but
 966          * first, make sure that an existing one isn't in
 967          * progress
 968          */
 969
 970         walk_revs_populate_todo(&todo_list, opts);
 971         if (create_seq_dir() < 0)
 972                 return -1;
 973         if (get_sha1("HEAD", sha1)) {
 974                 if (opts->action == REPLAY_REVERT)
 975                         return error(_("Can't revert as initial commit"));
 976                 return error(_("Can't cherry-pick into empty head"));
 977         }
 978         save_head(sha1_to_hex(sha1));
 979         save_opts(opts);
 980         return pick_commits(todo_list, opts);
 981 }