Merge branch 'rs/ref-transaction-1'
[git/git.git] / 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 const char sign_off_header[] = "Signed-off-by: ";
21 static const char cherry_picked_prefix[] = "(cherry picked from commit ";
22
23 static int is_rfc2822_line(const char *buf, int len)
24 {
25 int i;
26
27 for (i = 0; i < len; i++) {
28 int ch = buf[i];
29 if (ch == ':')
30 return 1;
31 if (!isalnum(ch) && ch != '-')
32 break;
33 }
34
35 return 0;
36 }
37
38 static int is_cherry_picked_from_line(const char *buf, int len)
39 {
40 /*
41 * We only care that it looks roughly like (cherry picked from ...)
42 */
43 return len > strlen(cherry_picked_prefix) + 1 &&
44 starts_with(buf, cherry_picked_prefix) && buf[len - 1] == ')';
45 }
46
47 /*
48 * Returns 0 for non-conforming footer
49 * Returns 1 for conforming footer
50 * Returns 2 when sob exists within conforming footer
51 * Returns 3 when sob exists within conforming footer as last entry
52 */
53 static int has_conforming_footer(struct strbuf *sb, struct strbuf *sob,
54 int ignore_footer)
55 {
56 char prev;
57 int i, k;
58 int len = sb->len - ignore_footer;
59 const char *buf = sb->buf;
60 int found_sob = 0;
61
62 /* footer must end with newline */
63 if (!len || buf[len - 1] != '\n')
64 return 0;
65
66 prev = '\0';
67 for (i = len - 1; i > 0; i--) {
68 char ch = buf[i];
69 if (prev == '\n' && ch == '\n') /* paragraph break */
70 break;
71 prev = ch;
72 }
73
74 /* require at least one blank line */
75 if (prev != '\n' || buf[i] != '\n')
76 return 0;
77
78 /* advance to start of last paragraph */
79 while (i < len - 1 && buf[i] == '\n')
80 i++;
81
82 for (; i < len; i = k) {
83 int found_rfc2822;
84
85 for (k = i; k < len && buf[k] != '\n'; k++)
86 ; /* do nothing */
87 k++;
88
89 found_rfc2822 = is_rfc2822_line(buf + i, k - i - 1);
90 if (found_rfc2822 && sob &&
91 !strncmp(buf + i, sob->buf, sob->len))
92 found_sob = k;
93
94 if (!(found_rfc2822 ||
95 is_cherry_picked_from_line(buf + i, k - i - 1)))
96 return 0;
97 }
98 if (found_sob == i)
99 return 3;
100 if (found_sob)
101 return 2;
102 return 1;
103 }
104
105 static void remove_sequencer_state(void)
106 {
107 struct strbuf seq_dir = STRBUF_INIT;
108
109 strbuf_addf(&seq_dir, "%s", git_path(SEQ_DIR));
110 remove_dir_recursively(&seq_dir, 0);
111 strbuf_release(&seq_dir);
112 }
113
114 static const char *action_name(const struct replay_opts *opts)
115 {
116 return opts->action == REPLAY_REVERT ? "revert" : "cherry-pick";
117 }
118
119 struct commit_message {
120 char *parent_label;
121 const char *label;
122 const char *subject;
123 const char *message;
124 };
125
126 static int get_message(struct commit *commit, struct commit_message *out)
127 {
128 const char *abbrev, *subject;
129 int abbrev_len, subject_len;
130 char *q;
131
132 if (!git_commit_encoding)
133 git_commit_encoding = "UTF-8";
134
135 out->message = logmsg_reencode(commit, NULL, git_commit_encoding);
136 abbrev = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV);
137 abbrev_len = strlen(abbrev);
138
139 subject_len = find_commit_subject(out->message, &subject);
140
141 out->parent_label = xmalloc(strlen("parent of ") + abbrev_len +
142 strlen("... ") + subject_len + 1);
143 q = out->parent_label;
144 q = mempcpy(q, "parent of ", strlen("parent of "));
145 out->label = q;
146 q = mempcpy(q, abbrev, abbrev_len);
147 q = mempcpy(q, "... ", strlen("... "));
148 out->subject = q;
149 q = mempcpy(q, subject, subject_len);
150 *q = '\0';
151 return 0;
152 }
153
154 static void free_message(struct commit *commit, struct commit_message *msg)
155 {
156 free(msg->parent_label);
157 unuse_commit_buffer(commit, msg->message);
158 }
159
160 static void write_cherry_pick_head(struct commit *commit, const char *pseudoref)
161 {
162 const char *filename;
163 int fd;
164 struct strbuf buf = STRBUF_INIT;
165
166 strbuf_addf(&buf, "%s\n", sha1_to_hex(commit->object.sha1));
167
168 filename = git_path("%s", pseudoref);
169 fd = open(filename, O_WRONLY | O_CREAT, 0666);
170 if (fd < 0)
171 die_errno(_("Could not open '%s' for writing"), filename);
172 if (write_in_full(fd, buf.buf, buf.len) != buf.len || close(fd))
173 die_errno(_("Could not write to '%s'"), filename);
174 strbuf_release(&buf);
175 }
176
177 static void print_advice(int show_hint, struct replay_opts *opts)
178 {
179 char *msg = getenv("GIT_CHERRY_PICK_HELP");
180
181 if (msg) {
182 fprintf(stderr, "%s\n", msg);
183 /*
184 * A conflict has occurred but the porcelain
185 * (typically rebase --interactive) wants to take care
186 * of the commit itself so remove CHERRY_PICK_HEAD
187 */
188 unlink(git_path("CHERRY_PICK_HEAD"));
189 return;
190 }
191
192 if (show_hint) {
193 if (opts->no_commit)
194 advise(_("after resolving the conflicts, mark the corrected paths\n"
195 "with 'git add <paths>' or 'git rm <paths>'"));
196 else
197 advise(_("after resolving the conflicts, mark the corrected paths\n"
198 "with 'git add <paths>' or 'git rm <paths>'\n"
199 "and commit the result with 'git commit'"));
200 }
201 }
202
203 static void write_message(struct strbuf *msgbuf, const char *filename)
204 {
205 static struct lock_file msg_file;
206
207 int msg_fd = hold_lock_file_for_update(&msg_file, filename,
208 LOCK_DIE_ON_ERROR);
209 if (write_in_full(msg_fd, msgbuf->buf, msgbuf->len) < 0)
210 die_errno(_("Could not write to %s"), filename);
211 strbuf_release(msgbuf);
212 if (commit_lock_file(&msg_file) < 0)
213 die(_("Error wrapping up %s"), filename);
214 }
215
216 static struct tree *empty_tree(void)
217 {
218 return lookup_tree(EMPTY_TREE_SHA1_BIN);
219 }
220
221 static int error_dirty_index(struct replay_opts *opts)
222 {
223 if (read_cache_unmerged())
224 return error_resolve_conflict(action_name(opts));
225
226 /* Different translation strings for cherry-pick and revert */
227 if (opts->action == REPLAY_PICK)
228 error(_("Your local changes would be overwritten by cherry-pick."));
229 else
230 error(_("Your local changes would be overwritten by revert."));
231
232 if (advice_commit_before_merge)
233 advise(_("Commit your changes or stash them to proceed."));
234 return -1;
235 }
236
237 static int fast_forward_to(const unsigned char *to, const unsigned char *from,
238 int unborn, struct replay_opts *opts)
239 {
240 struct ref_transaction *transaction;
241 struct strbuf sb = STRBUF_INIT;
242 struct strbuf err = STRBUF_INIT;
243
244 read_cache();
245 if (checkout_fast_forward(from, to, 1))
246 exit(128); /* the callee should have complained already */
247
248 strbuf_addf(&sb, "%s: fast-forward", action_name(opts));
249
250 transaction = ref_transaction_begin(&err);
251 if (!transaction ||
252 ref_transaction_update(transaction, "HEAD",
253 to, unborn ? null_sha1 : from,
254 0, 1, &err) ||
255 ref_transaction_commit(transaction, sb.buf, &err)) {
256 ref_transaction_free(transaction);
257 error("%s", err.buf);
258 strbuf_release(&sb);
259 strbuf_release(&err);
260 return -1;
261 }
262
263 strbuf_release(&sb);
264 strbuf_release(&err);
265 ref_transaction_free(transaction);
266 return 0;
267 }
268
269 static int do_recursive_merge(struct commit *base, struct commit *next,
270 const char *base_label, const char *next_label,
271 unsigned char *head, struct strbuf *msgbuf,
272 struct replay_opts *opts)
273 {
274 struct merge_options o;
275 struct tree *result, *next_tree, *base_tree, *head_tree;
276 int clean;
277 const char **xopt;
278 static struct lock_file index_lock;
279
280 hold_locked_index(&index_lock, 1);
281
282 read_cache();
283
284 init_merge_options(&o);
285 o.ancestor = base ? base_label : "(empty tree)";
286 o.branch1 = "HEAD";
287 o.branch2 = next ? next_label : "(empty tree)";
288
289 head_tree = parse_tree_indirect(head);
290 next_tree = next ? next->tree : empty_tree();
291 base_tree = base ? base->tree : empty_tree();
292
293 for (xopt = opts->xopts; xopt != opts->xopts + opts->xopts_nr; xopt++)
294 parse_merge_opt(&o, *xopt);
295
296 clean = merge_trees(&o,
297 head_tree,
298 next_tree, base_tree, &result);
299
300 if (active_cache_changed &&
301 write_locked_index(&the_index, &index_lock, COMMIT_LOCK))
302 /* TRANSLATORS: %s will be "revert" or "cherry-pick" */
303 die(_("%s: Unable to write new index file"), action_name(opts));
304 rollback_lock_file(&index_lock);
305
306 if (opts->signoff)
307 append_signoff(msgbuf, 0, 0);
308
309 if (!clean) {
310 int i;
311 strbuf_addstr(msgbuf, "\nConflicts:\n");
312 for (i = 0; i < active_nr;) {
313 const struct cache_entry *ce = active_cache[i++];
314 if (ce_stage(ce)) {
315 strbuf_addch(msgbuf, '\t');
316 strbuf_addstr(msgbuf, ce->name);
317 strbuf_addch(msgbuf, '\n');
318 while (i < active_nr && !strcmp(ce->name,
319 active_cache[i]->name))
320 i++;
321 }
322 }
323 }
324
325 return !clean;
326 }
327
328 static int is_index_unchanged(void)
329 {
330 unsigned char head_sha1[20];
331 struct commit *head_commit;
332
333 if (!resolve_ref_unsafe("HEAD", head_sha1, 1, NULL))
334 return error(_("Could not resolve HEAD commit\n"));
335
336 head_commit = lookup_commit(head_sha1);
337
338 /*
339 * If head_commit is NULL, check_commit, called from
340 * lookup_commit, would have indicated that head_commit is not
341 * a commit object already. parse_commit() will return failure
342 * without further complaints in such a case. Otherwise, if
343 * the commit is invalid, parse_commit() will complain. So
344 * there is nothing for us to say here. Just return failure.
345 */
346 if (parse_commit(head_commit))
347 return -1;
348
349 if (!active_cache_tree)
350 active_cache_tree = cache_tree();
351
352 if (!cache_tree_fully_valid(active_cache_tree))
353 if (cache_tree_update(&the_index, 0))
354 return error(_("Unable to update cache tree\n"));
355
356 return !hashcmp(active_cache_tree->sha1, head_commit->tree->object.sha1);
357 }
358
359 /*
360 * If we are cherry-pick, and if the merge did not result in
361 * hand-editing, we will hit this commit and inherit the original
362 * author date and name.
363 * If we are revert, or if our cherry-pick results in a hand merge,
364 * we had better say that the current user is responsible for that.
365 */
366 static int run_git_commit(const char *defmsg, struct replay_opts *opts,
367 int allow_empty)
368 {
369 struct argv_array array;
370 int rc;
371
372 argv_array_init(&array);
373 argv_array_push(&array, "commit");
374 argv_array_push(&array, "-n");
375
376 if (opts->gpg_sign)
377 argv_array_pushf(&array, "-S%s", opts->gpg_sign);
378 if (opts->signoff)
379 argv_array_push(&array, "-s");
380 if (!opts->edit) {
381 argv_array_push(&array, "-F");
382 argv_array_push(&array, defmsg);
383 }
384
385 if (allow_empty)
386 argv_array_push(&array, "--allow-empty");
387
388 if (opts->allow_empty_message)
389 argv_array_push(&array, "--allow-empty-message");
390
391 rc = run_command_v_opt(array.argv, RUN_GIT_CMD);
392 argv_array_clear(&array);
393 return rc;
394 }
395
396 static int is_original_commit_empty(struct commit *commit)
397 {
398 const unsigned char *ptree_sha1;
399
400 if (parse_commit(commit))
401 return error(_("Could not parse commit %s\n"),
402 sha1_to_hex(commit->object.sha1));
403 if (commit->parents) {
404 struct commit *parent = commit->parents->item;
405 if (parse_commit(parent))
406 return error(_("Could not parse parent commit %s\n"),
407 sha1_to_hex(parent->object.sha1));
408 ptree_sha1 = parent->tree->object.sha1;
409 } else {
410 ptree_sha1 = EMPTY_TREE_SHA1_BIN; /* commit is root */
411 }
412
413 return !hashcmp(ptree_sha1, commit->tree->object.sha1);
414 }
415
416 /*
417 * Do we run "git commit" with "--allow-empty"?
418 */
419 static int allow_empty(struct replay_opts *opts, struct commit *commit)
420 {
421 int index_unchanged, empty_commit;
422
423 /*
424 * Three cases:
425 *
426 * (1) we do not allow empty at all and error out.
427 *
428 * (2) we allow ones that were initially empty, but
429 * forbid the ones that become empty;
430 *
431 * (3) we allow both.
432 */
433 if (!opts->allow_empty)
434 return 0; /* let "git commit" barf as necessary */
435
436 index_unchanged = is_index_unchanged();
437 if (index_unchanged < 0)
438 return index_unchanged;
439 if (!index_unchanged)
440 return 0; /* we do not have to say --allow-empty */
441
442 if (opts->keep_redundant_commits)
443 return 1;
444
445 empty_commit = is_original_commit_empty(commit);
446 if (empty_commit < 0)
447 return empty_commit;
448 if (!empty_commit)
449 return 0;
450 else
451 return 1;
452 }
453
454 static int do_pick_commit(struct commit *commit, struct replay_opts *opts)
455 {
456 unsigned char head[20];
457 struct commit *base, *next, *parent;
458 const char *base_label, *next_label;
459 struct commit_message msg = { NULL, NULL, NULL, NULL };
460 char *defmsg = NULL;
461 struct strbuf msgbuf = STRBUF_INIT;
462 int res, unborn = 0, allow;
463
464 if (opts->no_commit) {
465 /*
466 * We do not intend to commit immediately. We just want to
467 * merge the differences in, so let's compute the tree
468 * that represents the "current" state for merge-recursive
469 * to work on.
470 */
471 if (write_cache_as_tree(head, 0, NULL))
472 die (_("Your index file is unmerged."));
473 } else {
474 unborn = get_sha1("HEAD", head);
475 if (unborn)
476 hashcpy(head, EMPTY_TREE_SHA1_BIN);
477 if (index_differs_from(unborn ? EMPTY_TREE_SHA1_HEX : "HEAD", 0))
478 return error_dirty_index(opts);
479 }
480 discard_cache();
481
482 if (!commit->parents) {
483 parent = NULL;
484 }
485 else if (commit->parents->next) {
486 /* Reverting or cherry-picking a merge commit */
487 int cnt;
488 struct commit_list *p;
489
490 if (!opts->mainline)
491 return error(_("Commit %s is a merge but no -m option was given."),
492 sha1_to_hex(commit->object.sha1));
493
494 for (cnt = 1, p = commit->parents;
495 cnt != opts->mainline && p;
496 cnt++)
497 p = p->next;
498 if (cnt != opts->mainline || !p)
499 return error(_("Commit %s does not have parent %d"),
500 sha1_to_hex(commit->object.sha1), opts->mainline);
501 parent = p->item;
502 } else if (0 < opts->mainline)
503 return error(_("Mainline was specified but commit %s is not a merge."),
504 sha1_to_hex(commit->object.sha1));
505 else
506 parent = commit->parents->item;
507
508 if (opts->allow_ff &&
509 ((parent && !hashcmp(parent->object.sha1, head)) ||
510 (!parent && unborn)))
511 return fast_forward_to(commit->object.sha1, head, unborn, opts);
512
513 if (parent && parse_commit(parent) < 0)
514 /* TRANSLATORS: The first %s will be "revert" or
515 "cherry-pick", the second %s a SHA1 */
516 return error(_("%s: cannot parse parent commit %s"),
517 action_name(opts), sha1_to_hex(parent->object.sha1));
518
519 if (get_message(commit, &msg) != 0)
520 return error(_("Cannot get commit message for %s"),
521 sha1_to_hex(commit->object.sha1));
522
523 /*
524 * "commit" is an existing commit. We would want to apply
525 * the difference it introduces since its first parent "prev"
526 * on top of the current HEAD if we are cherry-pick. Or the
527 * reverse of it if we are revert.
528 */
529
530 defmsg = git_pathdup("MERGE_MSG");
531
532 if (opts->action == REPLAY_REVERT) {
533 base = commit;
534 base_label = msg.label;
535 next = parent;
536 next_label = msg.parent_label;
537 strbuf_addstr(&msgbuf, "Revert \"");
538 strbuf_addstr(&msgbuf, msg.subject);
539 strbuf_addstr(&msgbuf, "\"\n\nThis reverts commit ");
540 strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));
541
542 if (commit->parents && commit->parents->next) {
543 strbuf_addstr(&msgbuf, ", reversing\nchanges made to ");
544 strbuf_addstr(&msgbuf, sha1_to_hex(parent->object.sha1));
545 }
546 strbuf_addstr(&msgbuf, ".\n");
547 } else {
548 const char *p;
549
550 base = parent;
551 base_label = msg.parent_label;
552 next = commit;
553 next_label = msg.label;
554
555 /*
556 * Append the commit log message to msgbuf; it starts
557 * after the tree, parent, author, committer
558 * information followed by "\n\n".
559 */
560 p = strstr(msg.message, "\n\n");
561 if (p) {
562 p += 2;
563 strbuf_addstr(&msgbuf, p);
564 }
565
566 if (opts->record_origin) {
567 if (!has_conforming_footer(&msgbuf, NULL, 0))
568 strbuf_addch(&msgbuf, '\n');
569 strbuf_addstr(&msgbuf, cherry_picked_prefix);
570 strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));
571 strbuf_addstr(&msgbuf, ")\n");
572 }
573 }
574
575 if (!opts->strategy || !strcmp(opts->strategy, "recursive") || opts->action == REPLAY_REVERT) {
576 res = do_recursive_merge(base, next, base_label, next_label,
577 head, &msgbuf, opts);
578 write_message(&msgbuf, defmsg);
579 } else {
580 struct commit_list *common = NULL;
581 struct commit_list *remotes = NULL;
582
583 write_message(&msgbuf, defmsg);
584
585 commit_list_insert(base, &common);
586 commit_list_insert(next, &remotes);
587 res = try_merge_command(opts->strategy, opts->xopts_nr, opts->xopts,
588 common, sha1_to_hex(head), remotes);
589 free_commit_list(common);
590 free_commit_list(remotes);
591 }
592
593 /*
594 * If the merge was clean or if it failed due to conflict, we write
595 * CHERRY_PICK_HEAD for the subsequent invocation of commit to use.
596 * However, if the merge did not even start, then we don't want to
597 * write it at all.
598 */
599 if (opts->action == REPLAY_PICK && !opts->no_commit && (res == 0 || res == 1))
600 write_cherry_pick_head(commit, "CHERRY_PICK_HEAD");
601 if (opts->action == REPLAY_REVERT && ((opts->no_commit && res == 0) || res == 1))
602 write_cherry_pick_head(commit, "REVERT_HEAD");
603
604 if (res) {
605 error(opts->action == REPLAY_REVERT
606 ? _("could not revert %s... %s")
607 : _("could not apply %s... %s"),
608 find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV),
609 msg.subject);
610 print_advice(res == 1, opts);
611 rerere(opts->allow_rerere_auto);
612 goto leave;
613 }
614
615 allow = allow_empty(opts, commit);
616 if (allow < 0) {
617 res = allow;
618 goto leave;
619 }
620 if (!opts->no_commit)
621 res = run_git_commit(defmsg, opts, allow);
622
623 leave:
624 free_message(commit, &msg);
625 free(defmsg);
626
627 return res;
628 }
629
630 static void prepare_revs(struct replay_opts *opts)
631 {
632 /*
633 * picking (but not reverting) ranges (but not individual revisions)
634 * should be done in reverse
635 */
636 if (opts->action == REPLAY_PICK && !opts->revs->no_walk)
637 opts->revs->reverse ^= 1;
638
639 if (prepare_revision_walk(opts->revs))
640 die(_("revision walk setup failed"));
641
642 if (!opts->revs->commits)
643 die(_("empty commit set passed"));
644 }
645
646 static void read_and_refresh_cache(struct replay_opts *opts)
647 {
648 static struct lock_file index_lock;
649 int index_fd = hold_locked_index(&index_lock, 0);
650 if (read_index_preload(&the_index, NULL) < 0)
651 die(_("git %s: failed to read the index"), action_name(opts));
652 refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED, NULL, NULL, NULL);
653 if (the_index.cache_changed && index_fd >= 0) {
654 if (write_locked_index(&the_index, &index_lock, COMMIT_LOCK))
655 die(_("git %s: failed to refresh the index"), action_name(opts));
656 }
657 rollback_lock_file(&index_lock);
658 }
659
660 static int format_todo(struct strbuf *buf, struct commit_list *todo_list,
661 struct replay_opts *opts)
662 {
663 struct commit_list *cur = NULL;
664 const char *sha1_abbrev = NULL;
665 const char *action_str = opts->action == REPLAY_REVERT ? "revert" : "pick";
666 const char *subject;
667 int subject_len;
668
669 for (cur = todo_list; cur; cur = cur->next) {
670 const char *commit_buffer = get_commit_buffer(cur->item, NULL);
671 sha1_abbrev = find_unique_abbrev(cur->item->object.sha1, DEFAULT_ABBREV);
672 subject_len = find_commit_subject(commit_buffer, &subject);
673 strbuf_addf(buf, "%s %s %.*s\n", action_str, sha1_abbrev,
674 subject_len, subject);
675 unuse_commit_buffer(cur->item, commit_buffer);
676 }
677 return 0;
678 }
679
680 static struct commit *parse_insn_line(char *bol, char *eol, struct replay_opts *opts)
681 {
682 unsigned char commit_sha1[20];
683 enum replay_action action;
684 char *end_of_object_name;
685 int saved, status, padding;
686
687 if (starts_with(bol, "pick")) {
688 action = REPLAY_PICK;
689 bol += strlen("pick");
690 } else if (starts_with(bol, "revert")) {
691 action = REPLAY_REVERT;
692 bol += strlen("revert");
693 } else
694 return NULL;
695
696 /* Eat up extra spaces/ tabs before object name */
697 padding = strspn(bol, " \t");
698 if (!padding)
699 return NULL;
700 bol += padding;
701
702 end_of_object_name = bol + strcspn(bol, " \t\n");
703 saved = *end_of_object_name;
704 *end_of_object_name = '\0';
705 status = get_sha1(bol, commit_sha1);
706 *end_of_object_name = saved;
707
708 /*
709 * Verify that the action matches up with the one in
710 * opts; we don't support arbitrary instructions
711 */
712 if (action != opts->action) {
713 const char *action_str;
714 action_str = action == REPLAY_REVERT ? "revert" : "cherry-pick";
715 error(_("Cannot %s during a %s"), action_str, action_name(opts));
716 return NULL;
717 }
718
719 if (status < 0)
720 return NULL;
721
722 return lookup_commit_reference(commit_sha1);
723 }
724
725 static int parse_insn_buffer(char *buf, struct commit_list **todo_list,
726 struct replay_opts *opts)
727 {
728 struct commit_list **next = todo_list;
729 struct commit *commit;
730 char *p = buf;
731 int i;
732
733 for (i = 1; *p; i++) {
734 char *eol = strchrnul(p, '\n');
735 commit = parse_insn_line(p, eol, opts);
736 if (!commit)
737 return error(_("Could not parse line %d."), i);
738 next = commit_list_append(commit, next);
739 p = *eol ? eol + 1 : eol;
740 }
741 if (!*todo_list)
742 return error(_("No commits parsed."));
743 return 0;
744 }
745
746 static void read_populate_todo(struct commit_list **todo_list,
747 struct replay_opts *opts)
748 {
749 const char *todo_file = git_path(SEQ_TODO_FILE);
750 struct strbuf buf = STRBUF_INIT;
751 int fd, res;
752
753 fd = open(todo_file, O_RDONLY);
754 if (fd < 0)
755 die_errno(_("Could not open %s"), todo_file);
756 if (strbuf_read(&buf, fd, 0) < 0) {
757 close(fd);
758 strbuf_release(&buf);
759 die(_("Could not read %s."), todo_file);
760 }
761 close(fd);
762
763 res = parse_insn_buffer(buf.buf, todo_list, opts);
764 strbuf_release(&buf);
765 if (res)
766 die(_("Unusable instruction sheet: %s"), todo_file);
767 }
768
769 static int populate_opts_cb(const char *key, const char *value, void *data)
770 {
771 struct replay_opts *opts = data;
772 int error_flag = 1;
773
774 if (!value)
775 error_flag = 0;
776 else if (!strcmp(key, "options.no-commit"))
777 opts->no_commit = git_config_bool_or_int(key, value, &error_flag);
778 else if (!strcmp(key, "options.edit"))
779 opts->edit = git_config_bool_or_int(key, value, &error_flag);
780 else if (!strcmp(key, "options.signoff"))
781 opts->signoff = git_config_bool_or_int(key, value, &error_flag);
782 else if (!strcmp(key, "options.record-origin"))
783 opts->record_origin = git_config_bool_or_int(key, value, &error_flag);
784 else if (!strcmp(key, "options.allow-ff"))
785 opts->allow_ff = git_config_bool_or_int(key, value, &error_flag);
786 else if (!strcmp(key, "options.mainline"))
787 opts->mainline = git_config_int(key, value);
788 else if (!strcmp(key, "options.strategy"))
789 git_config_string(&opts->strategy, key, value);
790 else if (!strcmp(key, "options.gpg-sign"))
791 git_config_string(&opts->gpg_sign, key, value);
792 else if (!strcmp(key, "options.strategy-option")) {
793 ALLOC_GROW(opts->xopts, opts->xopts_nr + 1, opts->xopts_alloc);
794 opts->xopts[opts->xopts_nr++] = xstrdup(value);
795 } else
796 return error(_("Invalid key: %s"), key);
797
798 if (!error_flag)
799 return error(_("Invalid value for %s: %s"), key, value);
800
801 return 0;
802 }
803
804 static void read_populate_opts(struct replay_opts **opts_ptr)
805 {
806 const char *opts_file = git_path(SEQ_OPTS_FILE);
807
808 if (!file_exists(opts_file))
809 return;
810 if (git_config_from_file(populate_opts_cb, opts_file, *opts_ptr) < 0)
811 die(_("Malformed options sheet: %s"), opts_file);
812 }
813
814 static void walk_revs_populate_todo(struct commit_list **todo_list,
815 struct replay_opts *opts)
816 {
817 struct commit *commit;
818 struct commit_list **next;
819
820 prepare_revs(opts);
821
822 next = todo_list;
823 while ((commit = get_revision(opts->revs)))
824 next = commit_list_append(commit, next);
825 }
826
827 static int create_seq_dir(void)
828 {
829 const char *seq_dir = git_path(SEQ_DIR);
830
831 if (file_exists(seq_dir)) {
832 error(_("a cherry-pick or revert is already in progress"));
833 advise(_("try \"git cherry-pick (--continue | --quit | --abort)\""));
834 return -1;
835 }
836 else if (mkdir(seq_dir, 0777) < 0)
837 die_errno(_("Could not create sequencer directory %s"), seq_dir);
838 return 0;
839 }
840
841 static void save_head(const char *head)
842 {
843 const char *head_file = git_path(SEQ_HEAD_FILE);
844 static struct lock_file head_lock;
845 struct strbuf buf = STRBUF_INIT;
846 int fd;
847
848 fd = hold_lock_file_for_update(&head_lock, head_file, LOCK_DIE_ON_ERROR);
849 strbuf_addf(&buf, "%s\n", head);
850 if (write_in_full(fd, buf.buf, buf.len) < 0)
851 die_errno(_("Could not write to %s"), head_file);
852 if (commit_lock_file(&head_lock) < 0)
853 die(_("Error wrapping up %s."), head_file);
854 }
855
856 static int reset_for_rollback(const unsigned char *sha1)
857 {
858 const char *argv[4]; /* reset --merge <arg> + NULL */
859 argv[0] = "reset";
860 argv[1] = "--merge";
861 argv[2] = sha1_to_hex(sha1);
862 argv[3] = NULL;
863 return run_command_v_opt(argv, RUN_GIT_CMD);
864 }
865
866 static int rollback_single_pick(void)
867 {
868 unsigned char head_sha1[20];
869
870 if (!file_exists(git_path("CHERRY_PICK_HEAD")) &&
871 !file_exists(git_path("REVERT_HEAD")))
872 return error(_("no cherry-pick or revert in progress"));
873 if (read_ref_full("HEAD", head_sha1, 0, NULL))
874 return error(_("cannot resolve HEAD"));
875 if (is_null_sha1(head_sha1))
876 return error(_("cannot abort from a branch yet to be born"));
877 return reset_for_rollback(head_sha1);
878 }
879
880 static int sequencer_rollback(struct replay_opts *opts)
881 {
882 const char *filename;
883 FILE *f;
884 unsigned char sha1[20];
885 struct strbuf buf = STRBUF_INIT;
886
887 filename = git_path(SEQ_HEAD_FILE);
888 f = fopen(filename, "r");
889 if (!f && errno == ENOENT) {
890 /*
891 * There is no multiple-cherry-pick in progress.
892 * If CHERRY_PICK_HEAD or REVERT_HEAD indicates
893 * a single-cherry-pick in progress, abort that.
894 */
895 return rollback_single_pick();
896 }
897 if (!f)
898 return error(_("cannot open %s: %s"), filename,
899 strerror(errno));
900 if (strbuf_getline(&buf, f, '\n')) {
901 error(_("cannot read %s: %s"), filename, ferror(f) ?
902 strerror(errno) : _("unexpected end of file"));
903 fclose(f);
904 goto fail;
905 }
906 fclose(f);
907 if (get_sha1_hex(buf.buf, sha1) || buf.buf[40] != '\0') {
908 error(_("stored pre-cherry-pick HEAD file '%s' is corrupt"),
909 filename);
910 goto fail;
911 }
912 if (reset_for_rollback(sha1))
913 goto fail;
914 remove_sequencer_state();
915 strbuf_release(&buf);
916 return 0;
917 fail:
918 strbuf_release(&buf);
919 return -1;
920 }
921
922 static void save_todo(struct commit_list *todo_list, struct replay_opts *opts)
923 {
924 const char *todo_file = git_path(SEQ_TODO_FILE);
925 static struct lock_file todo_lock;
926 struct strbuf buf = STRBUF_INIT;
927 int fd;
928
929 fd = hold_lock_file_for_update(&todo_lock, todo_file, LOCK_DIE_ON_ERROR);
930 if (format_todo(&buf, todo_list, opts) < 0)
931 die(_("Could not format %s."), todo_file);
932 if (write_in_full(fd, buf.buf, buf.len) < 0) {
933 strbuf_release(&buf);
934 die_errno(_("Could not write to %s"), todo_file);
935 }
936 if (commit_lock_file(&todo_lock) < 0) {
937 strbuf_release(&buf);
938 die(_("Error wrapping up %s."), todo_file);
939 }
940 strbuf_release(&buf);
941 }
942
943 static void save_opts(struct replay_opts *opts)
944 {
945 const char *opts_file = git_path(SEQ_OPTS_FILE);
946
947 if (opts->no_commit)
948 git_config_set_in_file(opts_file, "options.no-commit", "true");
949 if (opts->edit)
950 git_config_set_in_file(opts_file, "options.edit", "true");
951 if (opts->signoff)
952 git_config_set_in_file(opts_file, "options.signoff", "true");
953 if (opts->record_origin)
954 git_config_set_in_file(opts_file, "options.record-origin", "true");
955 if (opts->allow_ff)
956 git_config_set_in_file(opts_file, "options.allow-ff", "true");
957 if (opts->mainline) {
958 struct strbuf buf = STRBUF_INIT;
959 strbuf_addf(&buf, "%d", opts->mainline);
960 git_config_set_in_file(opts_file, "options.mainline", buf.buf);
961 strbuf_release(&buf);
962 }
963 if (opts->strategy)
964 git_config_set_in_file(opts_file, "options.strategy", opts->strategy);
965 if (opts->gpg_sign)
966 git_config_set_in_file(opts_file, "options.gpg-sign", opts->gpg_sign);
967 if (opts->xopts) {
968 int i;
969 for (i = 0; i < opts->xopts_nr; i++)
970 git_config_set_multivar_in_file(opts_file,
971 "options.strategy-option",
972 opts->xopts[i], "^$", 0);
973 }
974 }
975
976 static int pick_commits(struct commit_list *todo_list, struct replay_opts *opts)
977 {
978 struct commit_list *cur;
979 int res;
980
981 setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
982 if (opts->allow_ff)
983 assert(!(opts->signoff || opts->no_commit ||
984 opts->record_origin || opts->edit));
985 read_and_refresh_cache(opts);
986
987 for (cur = todo_list; cur; cur = cur->next) {
988 save_todo(cur, opts);
989 res = do_pick_commit(cur->item, opts);
990 if (res)
991 return res;
992 }
993
994 /*
995 * Sequence of picks finished successfully; cleanup by
996 * removing the .git/sequencer directory
997 */
998 remove_sequencer_state();
999 return 0;
1000 }
1001
1002 static int continue_single_pick(void)
1003 {
1004 const char *argv[] = { "commit", NULL };
1005
1006 if (!file_exists(git_path("CHERRY_PICK_HEAD")) &&
1007 !file_exists(git_path("REVERT_HEAD")))
1008 return error(_("no cherry-pick or revert in progress"));
1009 return run_command_v_opt(argv, RUN_GIT_CMD);
1010 }
1011
1012 static int sequencer_continue(struct replay_opts *opts)
1013 {
1014 struct commit_list *todo_list = NULL;
1015
1016 if (!file_exists(git_path(SEQ_TODO_FILE)))
1017 return continue_single_pick();
1018 read_populate_opts(&opts);
1019 read_populate_todo(&todo_list, opts);
1020
1021 /* Verify that the conflict has been resolved */
1022 if (file_exists(git_path("CHERRY_PICK_HEAD")) ||
1023 file_exists(git_path("REVERT_HEAD"))) {
1024 int ret = continue_single_pick();
1025 if (ret)
1026 return ret;
1027 }
1028 if (index_differs_from("HEAD", 0))
1029 return error_dirty_index(opts);
1030 todo_list = todo_list->next;
1031 return pick_commits(todo_list, opts);
1032 }
1033
1034 static int single_pick(struct commit *cmit, struct replay_opts *opts)
1035 {
1036 setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
1037 return do_pick_commit(cmit, opts);
1038 }
1039
1040 int sequencer_pick_revisions(struct replay_opts *opts)
1041 {
1042 struct commit_list *todo_list = NULL;
1043 unsigned char sha1[20];
1044 int i;
1045
1046 if (opts->subcommand == REPLAY_NONE)
1047 assert(opts->revs);
1048
1049 read_and_refresh_cache(opts);
1050
1051 /*
1052 * Decide what to do depending on the arguments; a fresh
1053 * cherry-pick should be handled differently from an existing
1054 * one that is being continued
1055 */
1056 if (opts->subcommand == REPLAY_REMOVE_STATE) {
1057 remove_sequencer_state();
1058 return 0;
1059 }
1060 if (opts->subcommand == REPLAY_ROLLBACK)
1061 return sequencer_rollback(opts);
1062 if (opts->subcommand == REPLAY_CONTINUE)
1063 return sequencer_continue(opts);
1064
1065 for (i = 0; i < opts->revs->pending.nr; i++) {
1066 unsigned char sha1[20];
1067 const char *name = opts->revs->pending.objects[i].name;
1068
1069 /* This happens when using --stdin. */
1070 if (!strlen(name))
1071 continue;
1072
1073 if (!get_sha1(name, sha1)) {
1074 if (!lookup_commit_reference_gently(sha1, 1)) {
1075 enum object_type type = sha1_object_info(sha1, NULL);
1076 die(_("%s: can't cherry-pick a %s"), name, typename(type));
1077 }
1078 } else
1079 die(_("%s: bad revision"), name);
1080 }
1081
1082 /*
1083 * If we were called as "git cherry-pick <commit>", just
1084 * cherry-pick/revert it, set CHERRY_PICK_HEAD /
1085 * REVERT_HEAD, and don't touch the sequencer state.
1086 * This means it is possible to cherry-pick in the middle
1087 * of a cherry-pick sequence.
1088 */
1089 if (opts->revs->cmdline.nr == 1 &&
1090 opts->revs->cmdline.rev->whence == REV_CMD_REV &&
1091 opts->revs->no_walk &&
1092 !opts->revs->cmdline.rev->flags) {
1093 struct commit *cmit;
1094 if (prepare_revision_walk(opts->revs))
1095 die(_("revision walk setup failed"));
1096 cmit = get_revision(opts->revs);
1097 if (!cmit || get_revision(opts->revs))
1098 die("BUG: expected exactly one commit from walk");
1099 return single_pick(cmit, opts);
1100 }
1101
1102 /*
1103 * Start a new cherry-pick/ revert sequence; but
1104 * first, make sure that an existing one isn't in
1105 * progress
1106 */
1107
1108 walk_revs_populate_todo(&todo_list, opts);
1109 if (create_seq_dir() < 0)
1110 return -1;
1111 if (get_sha1("HEAD", sha1)) {
1112 if (opts->action == REPLAY_REVERT)
1113 return error(_("Can't revert as initial commit"));
1114 return error(_("Can't cherry-pick into empty head"));
1115 }
1116 save_head(sha1_to_hex(sha1));
1117 save_opts(opts);
1118 return pick_commits(todo_list, opts);
1119 }
1120
1121 void append_signoff(struct strbuf *msgbuf, int ignore_footer, unsigned flag)
1122 {
1123 unsigned no_dup_sob = flag & APPEND_SIGNOFF_DEDUP;
1124 struct strbuf sob = STRBUF_INIT;
1125 int has_footer;
1126
1127 strbuf_addstr(&sob, sign_off_header);
1128 strbuf_addstr(&sob, fmt_name(getenv("GIT_COMMITTER_NAME"),
1129 getenv("GIT_COMMITTER_EMAIL")));
1130 strbuf_addch(&sob, '\n');
1131
1132 /*
1133 * If the whole message buffer is equal to the sob, pretend that we
1134 * found a conforming footer with a matching sob
1135 */
1136 if (msgbuf->len - ignore_footer == sob.len &&
1137 !strncmp(msgbuf->buf, sob.buf, sob.len))
1138 has_footer = 3;
1139 else
1140 has_footer = has_conforming_footer(msgbuf, &sob, ignore_footer);
1141
1142 if (!has_footer) {
1143 const char *append_newlines = NULL;
1144 size_t len = msgbuf->len - ignore_footer;
1145
1146 if (!len) {
1147 /*
1148 * The buffer is completely empty. Leave foom for
1149 * the title and body to be filled in by the user.
1150 */
1151 append_newlines = "\n\n";
1152 } else if (msgbuf->buf[len - 1] != '\n') {
1153 /*
1154 * Incomplete line. Complete the line and add a
1155 * blank one so that there is an empty line between
1156 * the message body and the sob.
1157 */
1158 append_newlines = "\n\n";
1159 } else if (len == 1) {
1160 /*
1161 * Buffer contains a single newline. Add another
1162 * so that we leave room for the title and body.
1163 */
1164 append_newlines = "\n";
1165 } else if (msgbuf->buf[len - 2] != '\n') {
1166 /*
1167 * Buffer ends with a single newline. Add another
1168 * so that there is an empty line between the message
1169 * body and the sob.
1170 */
1171 append_newlines = "\n";
1172 } /* else, the buffer already ends with two newlines. */
1173
1174 if (append_newlines)
1175 strbuf_splice(msgbuf, msgbuf->len - ignore_footer, 0,
1176 append_newlines, strlen(append_newlines));
1177 }
1178
1179 if (has_footer != 3 && (!no_dup_sob || has_footer != 2))
1180 strbuf_splice(msgbuf, msgbuf->len - ignore_footer, 0,
1181 sob.buf, sob.len);
1182
1183 strbuf_release(&sob);
1184 }