git cherry-pick: do not dereference a potential NULL pointer
[git/git.git] / sequencer.c
CommitLineData
26ae337b
RR
1#include "cache.h"
2#include "sequencer.h"
26ae337b 3#include "dir.h"
043a4492
RR
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"
b27cfb0d 16#include "argv-array.h"
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17
18#define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION"
26ae337b 19
d596118d 20void remove_sequencer_state(void)
26ae337b
RR
21{
22 struct strbuf seq_dir = STRBUF_INIT;
26ae337b
RR
23
24 strbuf_addf(&seq_dir, "%s", git_path(SEQ_DIR));
d596118d 25 remove_dir_recursively(&seq_dir, 0);
26ae337b 26 strbuf_release(&seq_dir);
26ae337b 27}
043a4492
RR
28
29static const char *action_name(const struct replay_opts *opts)
30{
31 return opts->action == REPLAY_REVERT ? "revert" : "cherry-pick";
32}
33
34static char *get_encoding(const char *message);
35
36struct commit_message {
37 char *parent_label;
38 const char *label;
39 const char *subject;
40 char *reencoded_message;
41 const char *message;
42};
43
44static 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
85static void free_message(struct commit_message *msg)
86{
87 free(msg->parent_label);
88 free(msg->reencoded_message);
89}
90
91static 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
110static 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
ed727b19 127static void print_advice(int show_hint, struct replay_opts *opts)
043a4492
RR
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
ed727b19
PH
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 }
043a4492
RR
151}
152
153static 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
166static struct tree *empty_tree(void)
167{
168 return lookup_tree((const unsigned char *)EMPTY_TREE_SHA1_BIN);
169}
170
171static 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
187static 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
198static 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\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
b27cfb0d
NH
255static 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);
4b580061
NH
264
265 /*
266 * If head_commit is NULL, check_commit, called from
267 * lookup_commit, would have indicated that head_commit is not
268 * a commit object already. parse_commit() will return failure
269 * without further complaints in such a case. Otherwise, if
270 * the commit is invalid, parse_commit() will complain. So
271 * there is nothing for us to say here. Just return failure.
272 */
273 if (parse_commit(head_commit))
274 return -1;
b27cfb0d
NH
275
276 if (!active_cache_tree)
277 active_cache_tree = cache_tree();
278
279 if (!cache_tree_fully_valid(active_cache_tree))
280 if (cache_tree_update(active_cache_tree, active_cache,
281 active_nr, 0))
282 return error(_("Unable to update cache tree\n"));
283
284 return !hashcmp(active_cache_tree->sha1, head_commit->tree->object.sha1);
285}
286
043a4492
RR
287/*
288 * If we are cherry-pick, and if the merge did not result in
289 * hand-editing, we will hit this commit and inherit the original
290 * author date and name.
291 * If we are revert, or if our cherry-pick results in a hand merge,
292 * we had better say that the current user is responsible for that.
293 */
294static int run_git_commit(const char *defmsg, struct replay_opts *opts)
295{
b27cfb0d
NH
296 struct argv_array array;
297 int rc;
298
299 argv_array_init(&array);
300 argv_array_push(&array, "commit");
301 argv_array_push(&array, "-n");
043a4492 302
043a4492 303 if (opts->signoff)
b27cfb0d 304 argv_array_push(&array, "-s");
043a4492 305 if (!opts->edit) {
b27cfb0d
NH
306 argv_array_push(&array, "-F");
307 argv_array_push(&array, defmsg);
043a4492 308 }
b27cfb0d 309
df478b74 310 if (opts->allow_empty)
b27cfb0d 311 argv_array_push(&array, "--allow-empty");
df478b74 312
b27cfb0d
NH
313 rc = run_command_v_opt(array.argv, RUN_GIT_CMD);
314 argv_array_clear(&array);
315 return rc;
316}
317
318static int is_original_commit_empty(struct commit *commit)
319{
320 const unsigned char *ptree_sha1;
321
322 if (parse_commit(commit))
323 return error(_("Could not parse commit %s\n"),
324 sha1_to_hex(commit->object.sha1));
325 if (commit->parents) {
326 struct commit *parent = commit->parents->item;
327 if (parse_commit(parent))
328 return error(_("Could not parse parent commit %s\n"),
329 sha1_to_hex(parent->object.sha1));
330 ptree_sha1 = parent->tree->object.sha1;
331 } else {
332 ptree_sha1 = EMPTY_TREE_SHA1_BIN; /* commit is root */
333 }
043a4492 334
b27cfb0d 335 return !hashcmp(ptree_sha1, commit->tree->object.sha1);
043a4492
RR
336}
337
338static int do_pick_commit(struct commit *commit, struct replay_opts *opts)
339{
340 unsigned char head[20];
341 struct commit *base, *next, *parent;
342 const char *base_label, *next_label;
343 struct commit_message msg = { NULL, NULL, NULL, NULL, NULL };
344 char *defmsg = NULL;
345 struct strbuf msgbuf = STRBUF_INIT;
346 int res;
b27cfb0d
NH
347 int empty_commit;
348 int index_unchanged;
043a4492
RR
349
350 if (opts->no_commit) {
351 /*
352 * We do not intend to commit immediately. We just want to
353 * merge the differences in, so let's compute the tree
354 * that represents the "current" state for merge-recursive
355 * to work on.
356 */
357 if (write_cache_as_tree(head, 0, NULL))
358 die (_("Your index file is unmerged."));
359 } else {
360 if (get_sha1("HEAD", head))
361 return error(_("You do not have a valid HEAD"));
362 if (index_differs_from("HEAD", 0))
363 return error_dirty_index(opts);
364 }
365 discard_cache();
366
367 if (!commit->parents) {
368 parent = NULL;
369 }
370 else if (commit->parents->next) {
371 /* Reverting or cherry-picking a merge commit */
372 int cnt;
373 struct commit_list *p;
374
375 if (!opts->mainline)
376 return error(_("Commit %s is a merge but no -m option was given."),
377 sha1_to_hex(commit->object.sha1));
378
379 for (cnt = 1, p = commit->parents;
380 cnt != opts->mainline && p;
381 cnt++)
382 p = p->next;
383 if (cnt != opts->mainline || !p)
384 return error(_("Commit %s does not have parent %d"),
385 sha1_to_hex(commit->object.sha1), opts->mainline);
386 parent = p->item;
387 } else if (0 < opts->mainline)
388 return error(_("Mainline was specified but commit %s is not a merge."),
389 sha1_to_hex(commit->object.sha1));
390 else
391 parent = commit->parents->item;
392
393 if (opts->allow_ff && parent && !hashcmp(parent->object.sha1, head))
394 return fast_forward_to(commit->object.sha1, head);
395
396 if (parent && parse_commit(parent) < 0)
397 /* TRANSLATORS: The first %s will be "revert" or
398 "cherry-pick", the second %s a SHA1 */
399 return error(_("%s: cannot parse parent commit %s"),
400 action_name(opts), sha1_to_hex(parent->object.sha1));
401
402 if (get_message(commit, &msg) != 0)
403 return error(_("Cannot get commit message for %s"),
404 sha1_to_hex(commit->object.sha1));
405
406 /*
407 * "commit" is an existing commit. We would want to apply
408 * the difference it introduces since its first parent "prev"
409 * on top of the current HEAD if we are cherry-pick. Or the
410 * reverse of it if we are revert.
411 */
412
413 defmsg = git_pathdup("MERGE_MSG");
414
415 if (opts->action == REPLAY_REVERT) {
416 base = commit;
417 base_label = msg.label;
418 next = parent;
419 next_label = msg.parent_label;
420 strbuf_addstr(&msgbuf, "Revert \"");
421 strbuf_addstr(&msgbuf, msg.subject);
422 strbuf_addstr(&msgbuf, "\"\n\nThis reverts commit ");
423 strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));
424
425 if (commit->parents && commit->parents->next) {
426 strbuf_addstr(&msgbuf, ", reversing\nchanges made to ");
427 strbuf_addstr(&msgbuf, sha1_to_hex(parent->object.sha1));
428 }
429 strbuf_addstr(&msgbuf, ".\n");
430 } else {
431 const char *p;
432
433 base = parent;
434 base_label = msg.parent_label;
435 next = commit;
436 next_label = msg.label;
437
438 /*
439 * Append the commit log message to msgbuf; it starts
440 * after the tree, parent, author, committer
441 * information followed by "\n\n".
442 */
443 p = strstr(msg.message, "\n\n");
444 if (p) {
445 p += 2;
446 strbuf_addstr(&msgbuf, p);
447 }
448
449 if (opts->record_origin) {
450 strbuf_addstr(&msgbuf, "(cherry picked from commit ");
451 strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));
452 strbuf_addstr(&msgbuf, ")\n");
453 }
454 }
455
456 if (!opts->strategy || !strcmp(opts->strategy, "recursive") || opts->action == REPLAY_REVERT) {
457 res = do_recursive_merge(base, next, base_label, next_label,
458 head, &msgbuf, opts);
459 write_message(&msgbuf, defmsg);
460 } else {
461 struct commit_list *common = NULL;
462 struct commit_list *remotes = NULL;
463
464 write_message(&msgbuf, defmsg);
465
466 commit_list_insert(base, &common);
467 commit_list_insert(next, &remotes);
468 res = try_merge_command(opts->strategy, opts->xopts_nr, opts->xopts,
469 common, sha1_to_hex(head), remotes);
470 free_commit_list(common);
471 free_commit_list(remotes);
472 }
473
b27cfb0d
NH
474 empty_commit = is_original_commit_empty(commit);
475 if (empty_commit < 0)
476 return empty_commit;
477
043a4492
RR
478 /*
479 * If the merge was clean or if it failed due to conflict, we write
480 * CHERRY_PICK_HEAD for the subsequent invocation of commit to use.
481 * However, if the merge did not even start, then we don't want to
482 * write it at all.
483 */
484 if (opts->action == REPLAY_PICK && !opts->no_commit && (res == 0 || res == 1))
485 write_cherry_pick_head(commit, "CHERRY_PICK_HEAD");
486 if (opts->action == REPLAY_REVERT && ((opts->no_commit && res == 0) || res == 1))
487 write_cherry_pick_head(commit, "REVERT_HEAD");
488
489 if (res) {
490 error(opts->action == REPLAY_REVERT
491 ? _("could not revert %s... %s")
492 : _("could not apply %s... %s"),
493 find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV),
494 msg.subject);
ed727b19 495 print_advice(res == 1, opts);
043a4492
RR
496 rerere(opts->allow_rerere_auto);
497 } else {
b27cfb0d
NH
498 index_unchanged = is_index_unchanged();
499 /*
500 * If index_unchanged is less than 0, that indicates we either
501 * couldn't parse HEAD or the index, so error out here.
502 */
503 if (index_unchanged < 0)
504 return index_unchanged;
505
506 if (!empty_commit && !opts->keep_redundant_commits && index_unchanged)
507 /*
508 * The head tree and the index match
509 * meaning the commit is empty. Since it wasn't created
510 * empty (based on the previous test), we can conclude
511 * the commit has been made redundant. Since we don't
512 * want to keep redundant commits, we can just return
513 * here, skipping this commit
514 */
515 return 0;
516
043a4492
RR
517 if (!opts->no_commit)
518 res = run_git_commit(defmsg, opts);
519 }
520
521 free_message(&msg);
522 free(defmsg);
523
524 return res;
525}
526
527static void prepare_revs(struct replay_opts *opts)
528{
529 if (opts->action != REPLAY_REVERT)
530 opts->revs->reverse ^= 1;
531
532 if (prepare_revision_walk(opts->revs))
533 die(_("revision walk setup failed"));
534
535 if (!opts->revs->commits)
536 die(_("empty commit set passed"));
537}
538
539static void read_and_refresh_cache(struct replay_opts *opts)
540{
541 static struct lock_file index_lock;
542 int index_fd = hold_locked_index(&index_lock, 0);
543 if (read_index_preload(&the_index, NULL) < 0)
544 die(_("git %s: failed to read the index"), action_name(opts));
545 refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED, NULL, NULL, NULL);
546 if (the_index.cache_changed) {
547 if (write_index(&the_index, index_fd) ||
548 commit_locked_index(&index_lock))
549 die(_("git %s: failed to refresh the index"), action_name(opts));
550 }
551 rollback_lock_file(&index_lock);
552}
553
554/*
555 * Append a commit to the end of the commit_list.
556 *
557 * next starts by pointing to the variable that holds the head of an
558 * empty commit_list, and is updated to point to the "next" field of
559 * the last item on the list as new commits are appended.
560 *
561 * Usage example:
562 *
563 * struct commit_list *list;
564 * struct commit_list **next = &list;
565 *
566 * next = commit_list_append(c1, next);
567 * next = commit_list_append(c2, next);
568 * assert(commit_list_count(list) == 2);
569 * return list;
570 */
571static struct commit_list **commit_list_append(struct commit *commit,
572 struct commit_list **next)
573{
574 struct commit_list *new = xmalloc(sizeof(struct commit_list));
575 new->item = commit;
576 *next = new;
577 new->next = NULL;
578 return &new->next;
579}
580
581static int format_todo(struct strbuf *buf, struct commit_list *todo_list,
582 struct replay_opts *opts)
583{
584 struct commit_list *cur = NULL;
585 const char *sha1_abbrev = NULL;
586 const char *action_str = opts->action == REPLAY_REVERT ? "revert" : "pick";
587 const char *subject;
588 int subject_len;
589
590 for (cur = todo_list; cur; cur = cur->next) {
591 sha1_abbrev = find_unique_abbrev(cur->item->object.sha1, DEFAULT_ABBREV);
592 subject_len = find_commit_subject(cur->item->buffer, &subject);
593 strbuf_addf(buf, "%s %s %.*s\n", action_str, sha1_abbrev,
594 subject_len, subject);
595 }
596 return 0;
597}
598
599static struct commit *parse_insn_line(char *bol, char *eol, struct replay_opts *opts)
600{
601 unsigned char commit_sha1[20];
602 enum replay_action action;
603 char *end_of_object_name;
604 int saved, status, padding;
605
606 if (!prefixcmp(bol, "pick")) {
607 action = REPLAY_PICK;
608 bol += strlen("pick");
609 } else if (!prefixcmp(bol, "revert")) {
610 action = REPLAY_REVERT;
611 bol += strlen("revert");
612 } else
613 return NULL;
614
615 /* Eat up extra spaces/ tabs before object name */
616 padding = strspn(bol, " \t");
617 if (!padding)
618 return NULL;
619 bol += padding;
620
621 end_of_object_name = bol + strcspn(bol, " \t\n");
622 saved = *end_of_object_name;
623 *end_of_object_name = '\0';
624 status = get_sha1(bol, commit_sha1);
625 *end_of_object_name = saved;
626
627 /*
628 * Verify that the action matches up with the one in
629 * opts; we don't support arbitrary instructions
630 */
631 if (action != opts->action) {
632 const char *action_str;
633 action_str = action == REPLAY_REVERT ? "revert" : "cherry-pick";
634 error(_("Cannot %s during a %s"), action_str, action_name(opts));
635 return NULL;
636 }
637
638 if (status < 0)
639 return NULL;
640
641 return lookup_commit_reference(commit_sha1);
642}
643
644static int parse_insn_buffer(char *buf, struct commit_list **todo_list,
645 struct replay_opts *opts)
646{
647 struct commit_list **next = todo_list;
648 struct commit *commit;
649 char *p = buf;
650 int i;
651
652 for (i = 1; *p; i++) {
653 char *eol = strchrnul(p, '\n');
654 commit = parse_insn_line(p, eol, opts);
655 if (!commit)
656 return error(_("Could not parse line %d."), i);
657 next = commit_list_append(commit, next);
658 p = *eol ? eol + 1 : eol;
659 }
660 if (!*todo_list)
661 return error(_("No commits parsed."));
662 return 0;
663}
664
665static void read_populate_todo(struct commit_list **todo_list,
666 struct replay_opts *opts)
667{
668 const char *todo_file = git_path(SEQ_TODO_FILE);
669 struct strbuf buf = STRBUF_INIT;
670 int fd, res;
671
672 fd = open(todo_file, O_RDONLY);
673 if (fd < 0)
674 die_errno(_("Could not open %s"), todo_file);
675 if (strbuf_read(&buf, fd, 0) < 0) {
676 close(fd);
677 strbuf_release(&buf);
678 die(_("Could not read %s."), todo_file);
679 }
680 close(fd);
681
682 res = parse_insn_buffer(buf.buf, todo_list, opts);
683 strbuf_release(&buf);
684 if (res)
685 die(_("Unusable instruction sheet: %s"), todo_file);
686}
687
688static int populate_opts_cb(const char *key, const char *value, void *data)
689{
690 struct replay_opts *opts = data;
691 int error_flag = 1;
692
693 if (!value)
694 error_flag = 0;
695 else if (!strcmp(key, "options.no-commit"))
696 opts->no_commit = git_config_bool_or_int(key, value, &error_flag);
697 else if (!strcmp(key, "options.edit"))
698 opts->edit = git_config_bool_or_int(key, value, &error_flag);
699 else if (!strcmp(key, "options.signoff"))
700 opts->signoff = git_config_bool_or_int(key, value, &error_flag);
701 else if (!strcmp(key, "options.record-origin"))
702 opts->record_origin = git_config_bool_or_int(key, value, &error_flag);
703 else if (!strcmp(key, "options.allow-ff"))
704 opts->allow_ff = git_config_bool_or_int(key, value, &error_flag);
705 else if (!strcmp(key, "options.mainline"))
706 opts->mainline = git_config_int(key, value);
707 else if (!strcmp(key, "options.strategy"))
708 git_config_string(&opts->strategy, key, value);
709 else if (!strcmp(key, "options.strategy-option")) {
710 ALLOC_GROW(opts->xopts, opts->xopts_nr + 1, opts->xopts_alloc);
711 opts->xopts[opts->xopts_nr++] = xstrdup(value);
712 } else
713 return error(_("Invalid key: %s"), key);
714
715 if (!error_flag)
716 return error(_("Invalid value for %s: %s"), key, value);
717
718 return 0;
719}
720
721static void read_populate_opts(struct replay_opts **opts_ptr)
722{
723 const char *opts_file = git_path(SEQ_OPTS_FILE);
724
725 if (!file_exists(opts_file))
726 return;
727 if (git_config_from_file(populate_opts_cb, opts_file, *opts_ptr) < 0)
728 die(_("Malformed options sheet: %s"), opts_file);
729}
730
731static void walk_revs_populate_todo(struct commit_list **todo_list,
732 struct replay_opts *opts)
733{
734 struct commit *commit;
735 struct commit_list **next;
736
737 prepare_revs(opts);
738
739 next = todo_list;
740 while ((commit = get_revision(opts->revs)))
741 next = commit_list_append(commit, next);
742}
743
744static int create_seq_dir(void)
745{
746 const char *seq_dir = git_path(SEQ_DIR);
747
748 if (file_exists(seq_dir)) {
749 error(_("a cherry-pick or revert is already in progress"));
750 advise(_("try \"git cherry-pick (--continue | --quit | --abort)\""));
751 return -1;
752 }
753 else if (mkdir(seq_dir, 0777) < 0)
754 die_errno(_("Could not create sequencer directory %s"), seq_dir);
755 return 0;
756}
757
758static void save_head(const char *head)
759{
760 const char *head_file = git_path(SEQ_HEAD_FILE);
761 static struct lock_file head_lock;
762 struct strbuf buf = STRBUF_INIT;
763 int fd;
764
765 fd = hold_lock_file_for_update(&head_lock, head_file, LOCK_DIE_ON_ERROR);
766 strbuf_addf(&buf, "%s\n", head);
767 if (write_in_full(fd, buf.buf, buf.len) < 0)
768 die_errno(_("Could not write to %s"), head_file);
769 if (commit_lock_file(&head_lock) < 0)
770 die(_("Error wrapping up %s."), head_file);
771}
772
773static int reset_for_rollback(const unsigned char *sha1)
774{
775 const char *argv[4]; /* reset --merge <arg> + NULL */
776 argv[0] = "reset";
777 argv[1] = "--merge";
778 argv[2] = sha1_to_hex(sha1);
779 argv[3] = NULL;
780 return run_command_v_opt(argv, RUN_GIT_CMD);
781}
782
783static int rollback_single_pick(void)
784{
785 unsigned char head_sha1[20];
786
787 if (!file_exists(git_path("CHERRY_PICK_HEAD")) &&
788 !file_exists(git_path("REVERT_HEAD")))
789 return error(_("no cherry-pick or revert in progress"));
790 if (read_ref_full("HEAD", head_sha1, 0, NULL))
791 return error(_("cannot resolve HEAD"));
792 if (is_null_sha1(head_sha1))
793 return error(_("cannot abort from a branch yet to be born"));
794 return reset_for_rollback(head_sha1);
795}
796
797static int sequencer_rollback(struct replay_opts *opts)
798{
799 const char *filename;
800 FILE *f;
801 unsigned char sha1[20];
802 struct strbuf buf = STRBUF_INIT;
803
804 filename = git_path(SEQ_HEAD_FILE);
805 f = fopen(filename, "r");
806 if (!f && errno == ENOENT) {
807 /*
808 * There is no multiple-cherry-pick in progress.
809 * If CHERRY_PICK_HEAD or REVERT_HEAD indicates
810 * a single-cherry-pick in progress, abort that.
811 */
812 return rollback_single_pick();
813 }
814 if (!f)
815 return error(_("cannot open %s: %s"), filename,
816 strerror(errno));
817 if (strbuf_getline(&buf, f, '\n')) {
818 error(_("cannot read %s: %s"), filename, ferror(f) ?
819 strerror(errno) : _("unexpected end of file"));
820 fclose(f);
821 goto fail;
822 }
823 fclose(f);
824 if (get_sha1_hex(buf.buf, sha1) || buf.buf[40] != '\0') {
825 error(_("stored pre-cherry-pick HEAD file '%s' is corrupt"),
826 filename);
827 goto fail;
828 }
829 if (reset_for_rollback(sha1))
830 goto fail;
831 remove_sequencer_state();
832 strbuf_release(&buf);
833 return 0;
834fail:
835 strbuf_release(&buf);
836 return -1;
837}
838
839static void save_todo(struct commit_list *todo_list, struct replay_opts *opts)
840{
841 const char *todo_file = git_path(SEQ_TODO_FILE);
842 static struct lock_file todo_lock;
843 struct strbuf buf = STRBUF_INIT;
844 int fd;
845
846 fd = hold_lock_file_for_update(&todo_lock, todo_file, LOCK_DIE_ON_ERROR);
847 if (format_todo(&buf, todo_list, opts) < 0)
848 die(_("Could not format %s."), todo_file);
849 if (write_in_full(fd, buf.buf, buf.len) < 0) {
850 strbuf_release(&buf);
851 die_errno(_("Could not write to %s"), todo_file);
852 }
853 if (commit_lock_file(&todo_lock) < 0) {
854 strbuf_release(&buf);
855 die(_("Error wrapping up %s."), todo_file);
856 }
857 strbuf_release(&buf);
858}
859
860static void save_opts(struct replay_opts *opts)
861{
862 const char *opts_file = git_path(SEQ_OPTS_FILE);
863
864 if (opts->no_commit)
865 git_config_set_in_file(opts_file, "options.no-commit", "true");
866 if (opts->edit)
867 git_config_set_in_file(opts_file, "options.edit", "true");
868 if (opts->signoff)
869 git_config_set_in_file(opts_file, "options.signoff", "true");
870 if (opts->record_origin)
871 git_config_set_in_file(opts_file, "options.record-origin", "true");
872 if (opts->allow_ff)
873 git_config_set_in_file(opts_file, "options.allow-ff", "true");
874 if (opts->mainline) {
875 struct strbuf buf = STRBUF_INIT;
876 strbuf_addf(&buf, "%d", opts->mainline);
877 git_config_set_in_file(opts_file, "options.mainline", buf.buf);
878 strbuf_release(&buf);
879 }
880 if (opts->strategy)
881 git_config_set_in_file(opts_file, "options.strategy", opts->strategy);
882 if (opts->xopts) {
883 int i;
884 for (i = 0; i < opts->xopts_nr; i++)
885 git_config_set_multivar_in_file(opts_file,
886 "options.strategy-option",
887 opts->xopts[i], "^$", 0);
888 }
889}
890
891static int pick_commits(struct commit_list *todo_list, struct replay_opts *opts)
892{
893 struct commit_list *cur;
894 int res;
895
896 setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
897 if (opts->allow_ff)
898 assert(!(opts->signoff || opts->no_commit ||
899 opts->record_origin || opts->edit));
900 read_and_refresh_cache(opts);
901
902 for (cur = todo_list; cur; cur = cur->next) {
903 save_todo(cur, opts);
904 res = do_pick_commit(cur->item, opts);
905 if (res)
906 return res;
907 }
908
909 /*
910 * Sequence of picks finished successfully; cleanup by
911 * removing the .git/sequencer directory
912 */
913 remove_sequencer_state();
914 return 0;
915}
916
917static int continue_single_pick(void)
918{
919 const char *argv[] = { "commit", NULL };
920
921 if (!file_exists(git_path("CHERRY_PICK_HEAD")) &&
922 !file_exists(git_path("REVERT_HEAD")))
923 return error(_("no cherry-pick or revert in progress"));
924 return run_command_v_opt(argv, RUN_GIT_CMD);
925}
926
927static int sequencer_continue(struct replay_opts *opts)
928{
929 struct commit_list *todo_list = NULL;
930
931 if (!file_exists(git_path(SEQ_TODO_FILE)))
932 return continue_single_pick();
933 read_populate_opts(&opts);
934 read_populate_todo(&todo_list, opts);
935
936 /* Verify that the conflict has been resolved */
937 if (file_exists(git_path("CHERRY_PICK_HEAD")) ||
938 file_exists(git_path("REVERT_HEAD"))) {
939 int ret = continue_single_pick();
940 if (ret)
941 return ret;
942 }
943 if (index_differs_from("HEAD", 0))
944 return error_dirty_index(opts);
945 todo_list = todo_list->next;
946 return pick_commits(todo_list, opts);
947}
948
949static int single_pick(struct commit *cmit, struct replay_opts *opts)
950{
951 setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
952 return do_pick_commit(cmit, opts);
953}
954
955int sequencer_pick_revisions(struct replay_opts *opts)
956{
957 struct commit_list *todo_list = NULL;
958 unsigned char sha1[20];
959
960 if (opts->subcommand == REPLAY_NONE)
961 assert(opts->revs);
962
963 read_and_refresh_cache(opts);
964
965 /*
966 * Decide what to do depending on the arguments; a fresh
967 * cherry-pick should be handled differently from an existing
968 * one that is being continued
969 */
970 if (opts->subcommand == REPLAY_REMOVE_STATE) {
971 remove_sequencer_state();
972 return 0;
973 }
974 if (opts->subcommand == REPLAY_ROLLBACK)
975 return sequencer_rollback(opts);
976 if (opts->subcommand == REPLAY_CONTINUE)
977 return sequencer_continue(opts);
978
979 /*
980 * If we were called as "git cherry-pick <commit>", just
981 * cherry-pick/revert it, set CHERRY_PICK_HEAD /
982 * REVERT_HEAD, and don't touch the sequencer state.
983 * This means it is possible to cherry-pick in the middle
984 * of a cherry-pick sequence.
985 */
986 if (opts->revs->cmdline.nr == 1 &&
987 opts->revs->cmdline.rev->whence == REV_CMD_REV &&
988 opts->revs->no_walk &&
989 !opts->revs->cmdline.rev->flags) {
990 struct commit *cmit;
991 if (prepare_revision_walk(opts->revs))
992 die(_("revision walk setup failed"));
993 cmit = get_revision(opts->revs);
994 if (!cmit || get_revision(opts->revs))
995 die("BUG: expected exactly one commit from walk");
996 return single_pick(cmit, opts);
997 }
998
999 /*
1000 * Start a new cherry-pick/ revert sequence; but
1001 * first, make sure that an existing one isn't in
1002 * progress
1003 */
1004
1005 walk_revs_populate_todo(&todo_list, opts);
1006 if (create_seq_dir() < 0)
1007 return -1;
1008 if (get_sha1("HEAD", sha1)) {
1009 if (opts->action == REPLAY_REVERT)
1010 return error(_("Can't revert as initial commit"));
1011 return error(_("Can't cherry-pick into empty head"));
1012 }
1013 save_head(sha1_to_hex(sha1));
1014 save_opts(opts);
1015 return pick_commits(todo_list, opts);
1016}