eb24add86688705901ba0b71a7f025289df03c9d
[git/git.git] / commit.c
1 #include "cache.h"
2 #include "tag.h"
3 #include "commit.h"
4 #include "pkt-line.h"
5 #include "utf8.h"
6 #include "diff.h"
7 #include "revision.h"
8 #include "notes.h"
9 #include "gpg-interface.h"
10 #include "mergesort.h"
11 #include "commit-slab.h"
12 #include "prio-queue.h"
13 #include "sha1-lookup.h"
14
15 static struct commit_extra_header *read_commit_extra_header_lines(const char *buf, size_t len, const char **);
16
17 int save_commit_buffer = 1;
18
19 const char *commit_type = "commit";
20
21 static struct commit *check_commit(struct object *obj,
22 const unsigned char *sha1,
23 int quiet)
24 {
25 if (obj->type != OBJ_COMMIT) {
26 if (!quiet)
27 error("Object %s is a %s, not a commit",
28 sha1_to_hex(sha1), typename(obj->type));
29 return NULL;
30 }
31 return (struct commit *) obj;
32 }
33
34 struct commit *lookup_commit_reference_gently(const unsigned char *sha1,
35 int quiet)
36 {
37 struct object *obj = deref_tag(parse_object(sha1), NULL, 0);
38
39 if (!obj)
40 return NULL;
41 return check_commit(obj, sha1, quiet);
42 }
43
44 struct commit *lookup_commit_reference(const unsigned char *sha1)
45 {
46 return lookup_commit_reference_gently(sha1, 0);
47 }
48
49 struct commit *lookup_commit_or_die(const unsigned char *sha1, const char *ref_name)
50 {
51 struct commit *c = lookup_commit_reference(sha1);
52 if (!c)
53 die(_("could not parse %s"), ref_name);
54 if (hashcmp(sha1, c->object.sha1)) {
55 warning(_("%s %s is not a commit!"),
56 ref_name, sha1_to_hex(sha1));
57 }
58 return c;
59 }
60
61 struct commit *lookup_commit(const unsigned char *sha1)
62 {
63 struct object *obj = lookup_object(sha1);
64 if (!obj)
65 return create_object(sha1, alloc_commit_node());
66 if (!obj->type)
67 obj->type = OBJ_COMMIT;
68 return check_commit(obj, sha1, 0);
69 }
70
71 struct commit *lookup_commit_reference_by_name(const char *name)
72 {
73 unsigned char sha1[20];
74 struct commit *commit;
75
76 if (get_sha1_committish(name, sha1))
77 return NULL;
78 commit = lookup_commit_reference(sha1);
79 if (parse_commit(commit))
80 return NULL;
81 return commit;
82 }
83
84 static unsigned long parse_commit_date(const char *buf, const char *tail)
85 {
86 const char *dateptr;
87
88 if (buf + 6 >= tail)
89 return 0;
90 if (memcmp(buf, "author", 6))
91 return 0;
92 while (buf < tail && *buf++ != '\n')
93 /* nada */;
94 if (buf + 9 >= tail)
95 return 0;
96 if (memcmp(buf, "committer", 9))
97 return 0;
98 while (buf < tail && *buf++ != '>')
99 /* nada */;
100 if (buf >= tail)
101 return 0;
102 dateptr = buf;
103 while (buf < tail && *buf++ != '\n')
104 /* nada */;
105 if (buf >= tail)
106 return 0;
107 /* dateptr < buf && buf[-1] == '\n', so strtoul will stop at buf-1 */
108 return strtoul(dateptr, NULL, 10);
109 }
110
111 static struct commit_graft **commit_graft;
112 static int commit_graft_alloc, commit_graft_nr;
113
114 static const unsigned char *commit_graft_sha1_access(size_t index, void *table)
115 {
116 struct commit_graft **commit_graft_table = table;
117 return commit_graft_table[index]->sha1;
118 }
119
120 static int commit_graft_pos(const unsigned char *sha1)
121 {
122 return sha1_pos(sha1, commit_graft, commit_graft_nr,
123 commit_graft_sha1_access);
124 }
125
126 int register_commit_graft(struct commit_graft *graft, int ignore_dups)
127 {
128 int pos = commit_graft_pos(graft->sha1);
129
130 if (0 <= pos) {
131 if (ignore_dups)
132 free(graft);
133 else {
134 free(commit_graft[pos]);
135 commit_graft[pos] = graft;
136 }
137 return 1;
138 }
139 pos = -pos - 1;
140 ALLOC_GROW(commit_graft, commit_graft_nr + 1, commit_graft_alloc);
141 commit_graft_nr++;
142 if (pos < commit_graft_nr)
143 memmove(commit_graft + pos + 1,
144 commit_graft + pos,
145 (commit_graft_nr - pos - 1) *
146 sizeof(*commit_graft));
147 commit_graft[pos] = graft;
148 return 0;
149 }
150
151 struct commit_graft *read_graft_line(char *buf, int len)
152 {
153 /* The format is just "Commit Parent1 Parent2 ...\n" */
154 int i;
155 struct commit_graft *graft = NULL;
156
157 while (len && isspace(buf[len-1]))
158 buf[--len] = '\0';
159 if (buf[0] == '#' || buf[0] == '\0')
160 return NULL;
161 if ((len + 1) % 41)
162 goto bad_graft_data;
163 i = (len + 1) / 41 - 1;
164 graft = xmalloc(sizeof(*graft) + 20 * i);
165 graft->nr_parent = i;
166 if (get_sha1_hex(buf, graft->sha1))
167 goto bad_graft_data;
168 for (i = 40; i < len; i += 41) {
169 if (buf[i] != ' ')
170 goto bad_graft_data;
171 if (get_sha1_hex(buf + i + 1, graft->parent[i/41]))
172 goto bad_graft_data;
173 }
174 return graft;
175
176 bad_graft_data:
177 error("bad graft data: %s", buf);
178 free(graft);
179 return NULL;
180 }
181
182 static int read_graft_file(const char *graft_file)
183 {
184 FILE *fp = fopen(graft_file, "r");
185 struct strbuf buf = STRBUF_INIT;
186 if (!fp)
187 return -1;
188 while (!strbuf_getwholeline(&buf, fp, '\n')) {
189 /* The format is just "Commit Parent1 Parent2 ...\n" */
190 struct commit_graft *graft = read_graft_line(buf.buf, buf.len);
191 if (!graft)
192 continue;
193 if (register_commit_graft(graft, 1))
194 error("duplicate graft data: %s", buf.buf);
195 }
196 fclose(fp);
197 strbuf_release(&buf);
198 return 0;
199 }
200
201 static void prepare_commit_graft(void)
202 {
203 static int commit_graft_prepared;
204 char *graft_file;
205
206 if (commit_graft_prepared)
207 return;
208 graft_file = get_graft_file();
209 read_graft_file(graft_file);
210 /* make sure shallows are read */
211 is_repository_shallow();
212 commit_graft_prepared = 1;
213 }
214
215 struct commit_graft *lookup_commit_graft(const unsigned char *sha1)
216 {
217 int pos;
218 prepare_commit_graft();
219 pos = commit_graft_pos(sha1);
220 if (pos < 0)
221 return NULL;
222 return commit_graft[pos];
223 }
224
225 int for_each_commit_graft(each_commit_graft_fn fn, void *cb_data)
226 {
227 int i, ret;
228 for (i = ret = 0; i < commit_graft_nr && !ret; i++)
229 ret = fn(commit_graft[i], cb_data);
230 return ret;
231 }
232
233 int unregister_shallow(const unsigned char *sha1)
234 {
235 int pos = commit_graft_pos(sha1);
236 if (pos < 0)
237 return -1;
238 if (pos + 1 < commit_graft_nr)
239 memmove(commit_graft + pos, commit_graft + pos + 1,
240 sizeof(struct commit_graft *)
241 * (commit_graft_nr - pos - 1));
242 commit_graft_nr--;
243 return 0;
244 }
245
246 struct commit_buffer {
247 void *buffer;
248 unsigned long size;
249 };
250 define_commit_slab(buffer_slab, struct commit_buffer);
251 static struct buffer_slab buffer_slab = COMMIT_SLAB_INIT(1, buffer_slab);
252
253 void set_commit_buffer(struct commit *commit, void *buffer, unsigned long size)
254 {
255 struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
256 v->buffer = buffer;
257 v->size = size;
258 }
259
260 const void *get_cached_commit_buffer(const struct commit *commit, unsigned long *sizep)
261 {
262 struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
263 if (sizep)
264 *sizep = v->size;
265 return v->buffer;
266 }
267
268 const void *get_commit_buffer(const struct commit *commit, unsigned long *sizep)
269 {
270 const void *ret = get_cached_commit_buffer(commit, sizep);
271 if (!ret) {
272 enum object_type type;
273 unsigned long size;
274 ret = read_sha1_file(commit->object.sha1, &type, &size);
275 if (!ret)
276 die("cannot read commit object %s",
277 sha1_to_hex(commit->object.sha1));
278 if (type != OBJ_COMMIT)
279 die("expected commit for %s, got %s",
280 sha1_to_hex(commit->object.sha1), typename(type));
281 if (sizep)
282 *sizep = size;
283 }
284 return ret;
285 }
286
287 void unuse_commit_buffer(const struct commit *commit, const void *buffer)
288 {
289 struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
290 if (v->buffer != buffer)
291 free((void *)buffer);
292 }
293
294 void free_commit_buffer(struct commit *commit)
295 {
296 struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
297 free(v->buffer);
298 v->buffer = NULL;
299 v->size = 0;
300 }
301
302 const void *detach_commit_buffer(struct commit *commit, unsigned long *sizep)
303 {
304 struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
305 void *ret;
306
307 ret = v->buffer;
308 if (sizep)
309 *sizep = v->size;
310
311 v->buffer = NULL;
312 v->size = 0;
313 return ret;
314 }
315
316 int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long size)
317 {
318 const char *tail = buffer;
319 const char *bufptr = buffer;
320 unsigned char parent[20];
321 struct commit_list **pptr;
322 struct commit_graft *graft;
323
324 if (item->object.parsed)
325 return 0;
326 item->object.parsed = 1;
327 tail += size;
328 if (tail <= bufptr + 46 || memcmp(bufptr, "tree ", 5) || bufptr[45] != '\n')
329 return error("bogus commit object %s", sha1_to_hex(item->object.sha1));
330 if (get_sha1_hex(bufptr + 5, parent) < 0)
331 return error("bad tree pointer in commit %s",
332 sha1_to_hex(item->object.sha1));
333 item->tree = lookup_tree(parent);
334 bufptr += 46; /* "tree " + "hex sha1" + "\n" */
335 pptr = &item->parents;
336
337 graft = lookup_commit_graft(item->object.sha1);
338 while (bufptr + 48 < tail && !memcmp(bufptr, "parent ", 7)) {
339 struct commit *new_parent;
340
341 if (tail <= bufptr + 48 ||
342 get_sha1_hex(bufptr + 7, parent) ||
343 bufptr[47] != '\n')
344 return error("bad parents in commit %s", sha1_to_hex(item->object.sha1));
345 bufptr += 48;
346 /*
347 * The clone is shallow if nr_parent < 0, and we must
348 * not traverse its real parents even when we unhide them.
349 */
350 if (graft && (graft->nr_parent < 0 || grafts_replace_parents))
351 continue;
352 new_parent = lookup_commit(parent);
353 if (new_parent)
354 pptr = &commit_list_insert(new_parent, pptr)->next;
355 }
356 if (graft) {
357 int i;
358 struct commit *new_parent;
359 for (i = 0; i < graft->nr_parent; i++) {
360 new_parent = lookup_commit(graft->parent[i]);
361 if (!new_parent)
362 continue;
363 pptr = &commit_list_insert(new_parent, pptr)->next;
364 }
365 }
366 item->date = parse_commit_date(bufptr, tail);
367
368 return 0;
369 }
370
371 int parse_commit(struct commit *item)
372 {
373 enum object_type type;
374 void *buffer;
375 unsigned long size;
376 int ret;
377
378 if (!item)
379 return -1;
380 if (item->object.parsed)
381 return 0;
382 buffer = read_sha1_file(item->object.sha1, &type, &size);
383 if (!buffer)
384 return error("Could not read %s",
385 sha1_to_hex(item->object.sha1));
386 if (type != OBJ_COMMIT) {
387 free(buffer);
388 return error("Object %s not a commit",
389 sha1_to_hex(item->object.sha1));
390 }
391 ret = parse_commit_buffer(item, buffer, size);
392 if (save_commit_buffer && !ret) {
393 set_commit_buffer(item, buffer, size);
394 return 0;
395 }
396 free(buffer);
397 return ret;
398 }
399
400 void parse_commit_or_die(struct commit *item)
401 {
402 if (parse_commit(item))
403 die("unable to parse commit %s",
404 item ? sha1_to_hex(item->object.sha1) : "(null)");
405 }
406
407 int find_commit_subject(const char *commit_buffer, const char **subject)
408 {
409 const char *eol;
410 const char *p = commit_buffer;
411
412 while (*p && (*p != '\n' || p[1] != '\n'))
413 p++;
414 if (*p) {
415 p += 2;
416 for (eol = p; *eol && *eol != '\n'; eol++)
417 ; /* do nothing */
418 } else
419 eol = p;
420
421 *subject = p;
422
423 return eol - p;
424 }
425
426 struct commit_list *commit_list_insert(struct commit *item, struct commit_list **list_p)
427 {
428 struct commit_list *new_list = xmalloc(sizeof(struct commit_list));
429 new_list->item = item;
430 new_list->next = *list_p;
431 *list_p = new_list;
432 return new_list;
433 }
434
435 unsigned commit_list_count(const struct commit_list *l)
436 {
437 unsigned c = 0;
438 for (; l; l = l->next )
439 c++;
440 return c;
441 }
442
443 struct commit_list *copy_commit_list(struct commit_list *list)
444 {
445 struct commit_list *head = NULL;
446 struct commit_list **pp = &head;
447 while (list) {
448 struct commit_list *new;
449 new = xmalloc(sizeof(struct commit_list));
450 new->item = list->item;
451 new->next = NULL;
452 *pp = new;
453 pp = &new->next;
454 list = list->next;
455 }
456 return head;
457 }
458
459 void free_commit_list(struct commit_list *list)
460 {
461 while (list) {
462 struct commit_list *temp = list;
463 list = temp->next;
464 free(temp);
465 }
466 }
467
468 struct commit_list * commit_list_insert_by_date(struct commit *item, struct commit_list **list)
469 {
470 struct commit_list **pp = list;
471 struct commit_list *p;
472 while ((p = *pp) != NULL) {
473 if (p->item->date < item->date) {
474 break;
475 }
476 pp = &p->next;
477 }
478 return commit_list_insert(item, pp);
479 }
480
481 static int commit_list_compare_by_date(const void *a, const void *b)
482 {
483 unsigned long a_date = ((const struct commit_list *)a)->item->date;
484 unsigned long b_date = ((const struct commit_list *)b)->item->date;
485 if (a_date < b_date)
486 return 1;
487 if (a_date > b_date)
488 return -1;
489 return 0;
490 }
491
492 static void *commit_list_get_next(const void *a)
493 {
494 return ((const struct commit_list *)a)->next;
495 }
496
497 static void commit_list_set_next(void *a, void *next)
498 {
499 ((struct commit_list *)a)->next = next;
500 }
501
502 void commit_list_sort_by_date(struct commit_list **list)
503 {
504 *list = llist_mergesort(*list, commit_list_get_next, commit_list_set_next,
505 commit_list_compare_by_date);
506 }
507
508 struct commit *pop_most_recent_commit(struct commit_list **list,
509 unsigned int mark)
510 {
511 struct commit *ret = (*list)->item;
512 struct commit_list *parents = ret->parents;
513 struct commit_list *old = *list;
514
515 *list = (*list)->next;
516 free(old);
517
518 while (parents) {
519 struct commit *commit = parents->item;
520 if (!parse_commit(commit) && !(commit->object.flags & mark)) {
521 commit->object.flags |= mark;
522 commit_list_insert_by_date(commit, list);
523 }
524 parents = parents->next;
525 }
526 return ret;
527 }
528
529 static void clear_commit_marks_1(struct commit_list **plist,
530 struct commit *commit, unsigned int mark)
531 {
532 while (commit) {
533 struct commit_list *parents;
534
535 if (!(mark & commit->object.flags))
536 return;
537
538 commit->object.flags &= ~mark;
539
540 parents = commit->parents;
541 if (!parents)
542 return;
543
544 while ((parents = parents->next))
545 commit_list_insert(parents->item, plist);
546
547 commit = commit->parents->item;
548 }
549 }
550
551 void clear_commit_marks_many(int nr, struct commit **commit, unsigned int mark)
552 {
553 struct commit_list *list = NULL;
554
555 while (nr--) {
556 commit_list_insert(*commit, &list);
557 commit++;
558 }
559 while (list)
560 clear_commit_marks_1(&list, pop_commit(&list), mark);
561 }
562
563 void clear_commit_marks(struct commit *commit, unsigned int mark)
564 {
565 clear_commit_marks_many(1, &commit, mark);
566 }
567
568 void clear_commit_marks_for_object_array(struct object_array *a, unsigned mark)
569 {
570 struct object *object;
571 struct commit *commit;
572 unsigned int i;
573
574 for (i = 0; i < a->nr; i++) {
575 object = a->objects[i].item;
576 commit = lookup_commit_reference_gently(object->sha1, 1);
577 if (commit)
578 clear_commit_marks(commit, mark);
579 }
580 }
581
582 struct commit *pop_commit(struct commit_list **stack)
583 {
584 struct commit_list *top = *stack;
585 struct commit *item = top ? top->item : NULL;
586
587 if (top) {
588 *stack = top->next;
589 free(top);
590 }
591 return item;
592 }
593
594 /*
595 * Topological sort support
596 */
597
598 /* count number of children that have not been emitted */
599 define_commit_slab(indegree_slab, int);
600
601 /* record author-date for each commit object */
602 define_commit_slab(author_date_slab, unsigned long);
603
604 static void record_author_date(struct author_date_slab *author_date,
605 struct commit *commit)
606 {
607 const char *buf, *line_end, *ident_line;
608 const char *buffer = get_commit_buffer(commit, NULL);
609 struct ident_split ident;
610 char *date_end;
611 unsigned long date;
612
613 for (buf = buffer; buf; buf = line_end + 1) {
614 line_end = strchrnul(buf, '\n');
615 ident_line = skip_prefix(buf, "author ");
616 if (!ident_line) {
617 if (!line_end[0] || line_end[1] == '\n')
618 return; /* end of header */
619 continue;
620 }
621 if (split_ident_line(&ident,
622 ident_line, line_end - ident_line) ||
623 !ident.date_begin || !ident.date_end)
624 goto fail_exit; /* malformed "author" line */
625 break;
626 }
627
628 date = strtoul(ident.date_begin, &date_end, 10);
629 if (date_end != ident.date_end)
630 goto fail_exit; /* malformed date */
631 *(author_date_slab_at(author_date, commit)) = date;
632
633 fail_exit:
634 unuse_commit_buffer(commit, buffer);
635 }
636
637 static int compare_commits_by_author_date(const void *a_, const void *b_,
638 void *cb_data)
639 {
640 const struct commit *a = a_, *b = b_;
641 struct author_date_slab *author_date = cb_data;
642 unsigned long a_date = *(author_date_slab_at(author_date, a));
643 unsigned long b_date = *(author_date_slab_at(author_date, b));
644
645 /* newer commits with larger date first */
646 if (a_date < b_date)
647 return 1;
648 else if (a_date > b_date)
649 return -1;
650 return 0;
651 }
652
653 int compare_commits_by_commit_date(const void *a_, const void *b_, void *unused)
654 {
655 const struct commit *a = a_, *b = b_;
656 /* newer commits with larger date first */
657 if (a->date < b->date)
658 return 1;
659 else if (a->date > b->date)
660 return -1;
661 return 0;
662 }
663
664 /*
665 * Performs an in-place topological sort on the list supplied.
666 */
667 void sort_in_topological_order(struct commit_list **list, enum rev_sort_order sort_order)
668 {
669 struct commit_list *next, *orig = *list;
670 struct commit_list **pptr;
671 struct indegree_slab indegree;
672 struct prio_queue queue;
673 struct commit *commit;
674 struct author_date_slab author_date;
675
676 if (!orig)
677 return;
678 *list = NULL;
679
680 init_indegree_slab(&indegree);
681 memset(&queue, '\0', sizeof(queue));
682
683 switch (sort_order) {
684 default: /* REV_SORT_IN_GRAPH_ORDER */
685 queue.compare = NULL;
686 break;
687 case REV_SORT_BY_COMMIT_DATE:
688 queue.compare = compare_commits_by_commit_date;
689 break;
690 case REV_SORT_BY_AUTHOR_DATE:
691 init_author_date_slab(&author_date);
692 queue.compare = compare_commits_by_author_date;
693 queue.cb_data = &author_date;
694 break;
695 }
696
697 /* Mark them and clear the indegree */
698 for (next = orig; next; next = next->next) {
699 struct commit *commit = next->item;
700 *(indegree_slab_at(&indegree, commit)) = 1;
701 /* also record the author dates, if needed */
702 if (sort_order == REV_SORT_BY_AUTHOR_DATE)
703 record_author_date(&author_date, commit);
704 }
705
706 /* update the indegree */
707 for (next = orig; next; next = next->next) {
708 struct commit_list *parents = next->item->parents;
709 while (parents) {
710 struct commit *parent = parents->item;
711 int *pi = indegree_slab_at(&indegree, parent);
712
713 if (*pi)
714 (*pi)++;
715 parents = parents->next;
716 }
717 }
718
719 /*
720 * find the tips
721 *
722 * tips are nodes not reachable from any other node in the list
723 *
724 * the tips serve as a starting set for the work queue.
725 */
726 for (next = orig; next; next = next->next) {
727 struct commit *commit = next->item;
728
729 if (*(indegree_slab_at(&indegree, commit)) == 1)
730 prio_queue_put(&queue, commit);
731 }
732
733 /*
734 * This is unfortunate; the initial tips need to be shown
735 * in the order given from the revision traversal machinery.
736 */
737 if (sort_order == REV_SORT_IN_GRAPH_ORDER)
738 prio_queue_reverse(&queue);
739
740 /* We no longer need the commit list */
741 free_commit_list(orig);
742
743 pptr = list;
744 *list = NULL;
745 while ((commit = prio_queue_get(&queue)) != NULL) {
746 struct commit_list *parents;
747
748 for (parents = commit->parents; parents ; parents = parents->next) {
749 struct commit *parent = parents->item;
750 int *pi = indegree_slab_at(&indegree, parent);
751
752 if (!*pi)
753 continue;
754
755 /*
756 * parents are only enqueued for emission
757 * when all their children have been emitted thereby
758 * guaranteeing topological order.
759 */
760 if (--(*pi) == 1)
761 prio_queue_put(&queue, parent);
762 }
763 /*
764 * all children of commit have already been
765 * emitted. we can emit it now.
766 */
767 *(indegree_slab_at(&indegree, commit)) = 0;
768
769 pptr = &commit_list_insert(commit, pptr)->next;
770 }
771
772 clear_indegree_slab(&indegree);
773 clear_prio_queue(&queue);
774 if (sort_order == REV_SORT_BY_AUTHOR_DATE)
775 clear_author_date_slab(&author_date);
776 }
777
778 /* merge-base stuff */
779
780 /* Remember to update object flag allocation in object.h */
781 #define PARENT1 (1u<<16)
782 #define PARENT2 (1u<<17)
783 #define STALE (1u<<18)
784 #define RESULT (1u<<19)
785
786 static const unsigned all_flags = (PARENT1 | PARENT2 | STALE | RESULT);
787
788 static struct commit *interesting(struct commit_list *list)
789 {
790 while (list) {
791 struct commit *commit = list->item;
792 list = list->next;
793 if (commit->object.flags & STALE)
794 continue;
795 return commit;
796 }
797 return NULL;
798 }
799
800 /* all input commits in one and twos[] must have been parsed! */
801 static struct commit_list *paint_down_to_common(struct commit *one, int n, struct commit **twos)
802 {
803 struct commit_list *list = NULL;
804 struct commit_list *result = NULL;
805 int i;
806
807 one->object.flags |= PARENT1;
808 commit_list_insert_by_date(one, &list);
809 if (!n)
810 return list;
811 for (i = 0; i < n; i++) {
812 twos[i]->object.flags |= PARENT2;
813 commit_list_insert_by_date(twos[i], &list);
814 }
815
816 while (interesting(list)) {
817 struct commit *commit;
818 struct commit_list *parents;
819 struct commit_list *next;
820 int flags;
821
822 commit = list->item;
823 next = list->next;
824 free(list);
825 list = next;
826
827 flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
828 if (flags == (PARENT1 | PARENT2)) {
829 if (!(commit->object.flags & RESULT)) {
830 commit->object.flags |= RESULT;
831 commit_list_insert_by_date(commit, &result);
832 }
833 /* Mark parents of a found merge stale */
834 flags |= STALE;
835 }
836 parents = commit->parents;
837 while (parents) {
838 struct commit *p = parents->item;
839 parents = parents->next;
840 if ((p->object.flags & flags) == flags)
841 continue;
842 if (parse_commit(p))
843 return NULL;
844 p->object.flags |= flags;
845 commit_list_insert_by_date(p, &list);
846 }
847 }
848
849 free_commit_list(list);
850 return result;
851 }
852
853 static struct commit_list *merge_bases_many(struct commit *one, int n, struct commit **twos)
854 {
855 struct commit_list *list = NULL;
856 struct commit_list *result = NULL;
857 int i;
858
859 for (i = 0; i < n; i++) {
860 if (one == twos[i])
861 /*
862 * We do not mark this even with RESULT so we do not
863 * have to clean it up.
864 */
865 return commit_list_insert(one, &result);
866 }
867
868 if (parse_commit(one))
869 return NULL;
870 for (i = 0; i < n; i++) {
871 if (parse_commit(twos[i]))
872 return NULL;
873 }
874
875 list = paint_down_to_common(one, n, twos);
876
877 while (list) {
878 struct commit_list *next = list->next;
879 if (!(list->item->object.flags & STALE))
880 commit_list_insert_by_date(list->item, &result);
881 free(list);
882 list = next;
883 }
884 return result;
885 }
886
887 struct commit_list *get_octopus_merge_bases(struct commit_list *in)
888 {
889 struct commit_list *i, *j, *k, *ret = NULL;
890
891 if (!in)
892 return ret;
893
894 commit_list_insert(in->item, &ret);
895
896 for (i = in->next; i; i = i->next) {
897 struct commit_list *new = NULL, *end = NULL;
898
899 for (j = ret; j; j = j->next) {
900 struct commit_list *bases;
901 bases = get_merge_bases(i->item, j->item, 1);
902 if (!new)
903 new = bases;
904 else
905 end->next = bases;
906 for (k = bases; k; k = k->next)
907 end = k;
908 }
909 ret = new;
910 }
911 return ret;
912 }
913
914 static int remove_redundant(struct commit **array, int cnt)
915 {
916 /*
917 * Some commit in the array may be an ancestor of
918 * another commit. Move such commit to the end of
919 * the array, and return the number of commits that
920 * are independent from each other.
921 */
922 struct commit **work;
923 unsigned char *redundant;
924 int *filled_index;
925 int i, j, filled;
926
927 work = xcalloc(cnt, sizeof(*work));
928 redundant = xcalloc(cnt, 1);
929 filled_index = xmalloc(sizeof(*filled_index) * (cnt - 1));
930
931 for (i = 0; i < cnt; i++)
932 parse_commit(array[i]);
933 for (i = 0; i < cnt; i++) {
934 struct commit_list *common;
935
936 if (redundant[i])
937 continue;
938 for (j = filled = 0; j < cnt; j++) {
939 if (i == j || redundant[j])
940 continue;
941 filled_index[filled] = j;
942 work[filled++] = array[j];
943 }
944 common = paint_down_to_common(array[i], filled, work);
945 if (array[i]->object.flags & PARENT2)
946 redundant[i] = 1;
947 for (j = 0; j < filled; j++)
948 if (work[j]->object.flags & PARENT1)
949 redundant[filled_index[j]] = 1;
950 clear_commit_marks(array[i], all_flags);
951 for (j = 0; j < filled; j++)
952 clear_commit_marks(work[j], all_flags);
953 free_commit_list(common);
954 }
955
956 /* Now collect the result */
957 memcpy(work, array, sizeof(*array) * cnt);
958 for (i = filled = 0; i < cnt; i++)
959 if (!redundant[i])
960 array[filled++] = work[i];
961 for (j = filled, i = 0; i < cnt; i++)
962 if (redundant[i])
963 array[j++] = work[i];
964 free(work);
965 free(redundant);
966 free(filled_index);
967 return filled;
968 }
969
970 struct commit_list *get_merge_bases_many(struct commit *one,
971 int n,
972 struct commit **twos,
973 int cleanup)
974 {
975 struct commit_list *list;
976 struct commit **rslt;
977 struct commit_list *result;
978 int cnt, i;
979
980 result = merge_bases_many(one, n, twos);
981 for (i = 0; i < n; i++) {
982 if (one == twos[i])
983 return result;
984 }
985 if (!result || !result->next) {
986 if (cleanup) {
987 clear_commit_marks(one, all_flags);
988 clear_commit_marks_many(n, twos, all_flags);
989 }
990 return result;
991 }
992
993 /* There are more than one */
994 cnt = 0;
995 list = result;
996 while (list) {
997 list = list->next;
998 cnt++;
999 }
1000 rslt = xcalloc(cnt, sizeof(*rslt));
1001 for (list = result, i = 0; list; list = list->next)
1002 rslt[i++] = list->item;
1003 free_commit_list(result);
1004
1005 clear_commit_marks(one, all_flags);
1006 clear_commit_marks_many(n, twos, all_flags);
1007
1008 cnt = remove_redundant(rslt, cnt);
1009 result = NULL;
1010 for (i = 0; i < cnt; i++)
1011 commit_list_insert_by_date(rslt[i], &result);
1012 free(rslt);
1013 return result;
1014 }
1015
1016 struct commit_list *get_merge_bases(struct commit *one, struct commit *two,
1017 int cleanup)
1018 {
1019 return get_merge_bases_many(one, 1, &two, cleanup);
1020 }
1021
1022 /*
1023 * Is "commit" a descendant of one of the elements on the "with_commit" list?
1024 */
1025 int is_descendant_of(struct commit *commit, struct commit_list *with_commit)
1026 {
1027 if (!with_commit)
1028 return 1;
1029 while (with_commit) {
1030 struct commit *other;
1031
1032 other = with_commit->item;
1033 with_commit = with_commit->next;
1034 if (in_merge_bases(other, commit))
1035 return 1;
1036 }
1037 return 0;
1038 }
1039
1040 /*
1041 * Is "commit" an ancestor of one of the "references"?
1042 */
1043 int in_merge_bases_many(struct commit *commit, int nr_reference, struct commit **reference)
1044 {
1045 struct commit_list *bases;
1046 int ret = 0, i;
1047
1048 if (parse_commit(commit))
1049 return ret;
1050 for (i = 0; i < nr_reference; i++)
1051 if (parse_commit(reference[i]))
1052 return ret;
1053
1054 bases = paint_down_to_common(commit, nr_reference, reference);
1055 if (commit->object.flags & PARENT2)
1056 ret = 1;
1057 clear_commit_marks(commit, all_flags);
1058 clear_commit_marks_many(nr_reference, reference, all_flags);
1059 free_commit_list(bases);
1060 return ret;
1061 }
1062
1063 /*
1064 * Is "commit" an ancestor of (i.e. reachable from) the "reference"?
1065 */
1066 int in_merge_bases(struct commit *commit, struct commit *reference)
1067 {
1068 return in_merge_bases_many(commit, 1, &reference);
1069 }
1070
1071 struct commit_list *reduce_heads(struct commit_list *heads)
1072 {
1073 struct commit_list *p;
1074 struct commit_list *result = NULL, **tail = &result;
1075 struct commit **array;
1076 int num_head, i;
1077
1078 if (!heads)
1079 return NULL;
1080
1081 /* Uniquify */
1082 for (p = heads; p; p = p->next)
1083 p->item->object.flags &= ~STALE;
1084 for (p = heads, num_head = 0; p; p = p->next) {
1085 if (p->item->object.flags & STALE)
1086 continue;
1087 p->item->object.flags |= STALE;
1088 num_head++;
1089 }
1090 array = xcalloc(num_head, sizeof(*array));
1091 for (p = heads, i = 0; p; p = p->next) {
1092 if (p->item->object.flags & STALE) {
1093 array[i++] = p->item;
1094 p->item->object.flags &= ~STALE;
1095 }
1096 }
1097 num_head = remove_redundant(array, num_head);
1098 for (i = 0; i < num_head; i++)
1099 tail = &commit_list_insert(array[i], tail)->next;
1100 return result;
1101 }
1102
1103 static const char gpg_sig_header[] = "gpgsig";
1104 static const int gpg_sig_header_len = sizeof(gpg_sig_header) - 1;
1105
1106 static int do_sign_commit(struct strbuf *buf, const char *keyid)
1107 {
1108 struct strbuf sig = STRBUF_INIT;
1109 int inspos, copypos;
1110
1111 /* find the end of the header */
1112 inspos = strstr(buf->buf, "\n\n") - buf->buf + 1;
1113
1114 if (!keyid || !*keyid)
1115 keyid = get_signing_key();
1116 if (sign_buffer(buf, &sig, keyid)) {
1117 strbuf_release(&sig);
1118 return -1;
1119 }
1120
1121 for (copypos = 0; sig.buf[copypos]; ) {
1122 const char *bol = sig.buf + copypos;
1123 const char *eol = strchrnul(bol, '\n');
1124 int len = (eol - bol) + !!*eol;
1125
1126 if (!copypos) {
1127 strbuf_insert(buf, inspos, gpg_sig_header, gpg_sig_header_len);
1128 inspos += gpg_sig_header_len;
1129 }
1130 strbuf_insert(buf, inspos++, " ", 1);
1131 strbuf_insert(buf, inspos, bol, len);
1132 inspos += len;
1133 copypos += len;
1134 }
1135 strbuf_release(&sig);
1136 return 0;
1137 }
1138
1139 int parse_signed_commit(const struct commit *commit,
1140 struct strbuf *payload, struct strbuf *signature)
1141 {
1142
1143 unsigned long size;
1144 const char *buffer = get_commit_buffer(commit, &size);
1145 int in_signature, saw_signature = -1;
1146 const char *line, *tail;
1147
1148 line = buffer;
1149 tail = buffer + size;
1150 in_signature = 0;
1151 saw_signature = 0;
1152 while (line < tail) {
1153 const char *sig = NULL;
1154 const char *next = memchr(line, '\n', tail - line);
1155
1156 next = next ? next + 1 : tail;
1157 if (in_signature && line[0] == ' ')
1158 sig = line + 1;
1159 else if (starts_with(line, gpg_sig_header) &&
1160 line[gpg_sig_header_len] == ' ')
1161 sig = line + gpg_sig_header_len + 1;
1162 if (sig) {
1163 strbuf_add(signature, sig, next - sig);
1164 saw_signature = 1;
1165 in_signature = 1;
1166 } else {
1167 if (*line == '\n')
1168 /* dump the whole remainder of the buffer */
1169 next = tail;
1170 strbuf_add(payload, line, next - line);
1171 in_signature = 0;
1172 }
1173 line = next;
1174 }
1175 unuse_commit_buffer(commit, buffer);
1176 return saw_signature;
1177 }
1178
1179 static void handle_signed_tag(struct commit *parent, struct commit_extra_header ***tail)
1180 {
1181 struct merge_remote_desc *desc;
1182 struct commit_extra_header *mergetag;
1183 char *buf;
1184 unsigned long size, len;
1185 enum object_type type;
1186
1187 desc = merge_remote_util(parent);
1188 if (!desc || !desc->obj)
1189 return;
1190 buf = read_sha1_file(desc->obj->sha1, &type, &size);
1191 if (!buf || type != OBJ_TAG)
1192 goto free_return;
1193 len = parse_signature(buf, size);
1194 if (size == len)
1195 goto free_return;
1196 /*
1197 * We could verify this signature and either omit the tag when
1198 * it does not validate, but the integrator may not have the
1199 * public key of the signer of the tag he is merging, while a
1200 * later auditor may have it while auditing, so let's not run
1201 * verify-signed-buffer here for now...
1202 *
1203 * if (verify_signed_buffer(buf, len, buf + len, size - len, ...))
1204 * warn("warning: signed tag unverified.");
1205 */
1206 mergetag = xcalloc(1, sizeof(*mergetag));
1207 mergetag->key = xstrdup("mergetag");
1208 mergetag->value = buf;
1209 mergetag->len = size;
1210
1211 **tail = mergetag;
1212 *tail = &mergetag->next;
1213 return;
1214
1215 free_return:
1216 free(buf);
1217 }
1218
1219 static struct {
1220 char result;
1221 const char *check;
1222 } sigcheck_gpg_status[] = {
1223 { 'G', "\n[GNUPG:] GOODSIG " },
1224 { 'B', "\n[GNUPG:] BADSIG " },
1225 { 'U', "\n[GNUPG:] TRUST_NEVER" },
1226 { 'U', "\n[GNUPG:] TRUST_UNDEFINED" },
1227 };
1228
1229 static void parse_gpg_output(struct signature_check *sigc)
1230 {
1231 const char *buf = sigc->gpg_status;
1232 int i;
1233
1234 /* Iterate over all search strings */
1235 for (i = 0; i < ARRAY_SIZE(sigcheck_gpg_status); i++) {
1236 const char *found, *next;
1237
1238 found = skip_prefix(buf, sigcheck_gpg_status[i].check + 1);
1239 if (!found) {
1240 found = strstr(buf, sigcheck_gpg_status[i].check);
1241 if (!found)
1242 continue;
1243 found += strlen(sigcheck_gpg_status[i].check);
1244 }
1245 sigc->result = sigcheck_gpg_status[i].result;
1246 /* The trust messages are not followed by key/signer information */
1247 if (sigc->result != 'U') {
1248 sigc->key = xmemdupz(found, 16);
1249 found += 17;
1250 next = strchrnul(found, '\n');
1251 sigc->signer = xmemdupz(found, next - found);
1252 }
1253 }
1254 }
1255
1256 void check_commit_signature(const struct commit* commit, struct signature_check *sigc)
1257 {
1258 struct strbuf payload = STRBUF_INIT;
1259 struct strbuf signature = STRBUF_INIT;
1260 struct strbuf gpg_output = STRBUF_INIT;
1261 struct strbuf gpg_status = STRBUF_INIT;
1262 int status;
1263
1264 sigc->result = 'N';
1265
1266 if (parse_signed_commit(commit, &payload, &signature) <= 0)
1267 goto out;
1268 status = verify_signed_buffer(payload.buf, payload.len,
1269 signature.buf, signature.len,
1270 &gpg_output, &gpg_status);
1271 if (status && !gpg_output.len)
1272 goto out;
1273 sigc->gpg_output = strbuf_detach(&gpg_output, NULL);
1274 sigc->gpg_status = strbuf_detach(&gpg_status, NULL);
1275 parse_gpg_output(sigc);
1276
1277 out:
1278 strbuf_release(&gpg_status);
1279 strbuf_release(&gpg_output);
1280 strbuf_release(&payload);
1281 strbuf_release(&signature);
1282 }
1283
1284
1285
1286 void append_merge_tag_headers(struct commit_list *parents,
1287 struct commit_extra_header ***tail)
1288 {
1289 while (parents) {
1290 struct commit *parent = parents->item;
1291 handle_signed_tag(parent, tail);
1292 parents = parents->next;
1293 }
1294 }
1295
1296 static void add_extra_header(struct strbuf *buffer,
1297 struct commit_extra_header *extra)
1298 {
1299 strbuf_addstr(buffer, extra->key);
1300 if (extra->len)
1301 strbuf_add_lines(buffer, " ", extra->value, extra->len);
1302 else
1303 strbuf_addch(buffer, '\n');
1304 }
1305
1306 struct commit_extra_header *read_commit_extra_headers(struct commit *commit,
1307 const char **exclude)
1308 {
1309 struct commit_extra_header *extra = NULL;
1310 unsigned long size;
1311 const char *buffer = get_commit_buffer(commit, &size);
1312 extra = read_commit_extra_header_lines(buffer, size, exclude);
1313 unuse_commit_buffer(commit, buffer);
1314 return extra;
1315 }
1316
1317 static inline int standard_header_field(const char *field, size_t len)
1318 {
1319 return ((len == 4 && !memcmp(field, "tree ", 5)) ||
1320 (len == 6 && !memcmp(field, "parent ", 7)) ||
1321 (len == 6 && !memcmp(field, "author ", 7)) ||
1322 (len == 9 && !memcmp(field, "committer ", 10)) ||
1323 (len == 8 && !memcmp(field, "encoding ", 9)));
1324 }
1325
1326 static int excluded_header_field(const char *field, size_t len, const char **exclude)
1327 {
1328 if (!exclude)
1329 return 0;
1330
1331 while (*exclude) {
1332 size_t xlen = strlen(*exclude);
1333 if (len == xlen &&
1334 !memcmp(field, *exclude, xlen) && field[xlen] == ' ')
1335 return 1;
1336 exclude++;
1337 }
1338 return 0;
1339 }
1340
1341 static struct commit_extra_header *read_commit_extra_header_lines(
1342 const char *buffer, size_t size,
1343 const char **exclude)
1344 {
1345 struct commit_extra_header *extra = NULL, **tail = &extra, *it = NULL;
1346 const char *line, *next, *eof, *eob;
1347 struct strbuf buf = STRBUF_INIT;
1348
1349 for (line = buffer, eob = line + size;
1350 line < eob && *line != '\n';
1351 line = next) {
1352 next = memchr(line, '\n', eob - line);
1353 next = next ? next + 1 : eob;
1354 if (*line == ' ') {
1355 /* continuation */
1356 if (it)
1357 strbuf_add(&buf, line + 1, next - (line + 1));
1358 continue;
1359 }
1360 if (it)
1361 it->value = strbuf_detach(&buf, &it->len);
1362 strbuf_reset(&buf);
1363 it = NULL;
1364
1365 eof = strchr(line, ' ');
1366 if (next <= eof)
1367 eof = next;
1368
1369 if (standard_header_field(line, eof - line) ||
1370 excluded_header_field(line, eof - line, exclude))
1371 continue;
1372
1373 it = xcalloc(1, sizeof(*it));
1374 it->key = xmemdupz(line, eof-line);
1375 *tail = it;
1376 tail = &it->next;
1377 if (eof + 1 < next)
1378 strbuf_add(&buf, eof + 1, next - (eof + 1));
1379 }
1380 if (it)
1381 it->value = strbuf_detach(&buf, &it->len);
1382 return extra;
1383 }
1384
1385 void free_commit_extra_headers(struct commit_extra_header *extra)
1386 {
1387 while (extra) {
1388 struct commit_extra_header *next = extra->next;
1389 free(extra->key);
1390 free(extra->value);
1391 free(extra);
1392 extra = next;
1393 }
1394 }
1395
1396 int commit_tree(const char *msg, size_t msg_len,
1397 const unsigned char *tree,
1398 struct commit_list *parents, unsigned char *ret,
1399 const char *author, const char *sign_commit)
1400 {
1401 struct commit_extra_header *extra = NULL, **tail = &extra;
1402 int result;
1403
1404 append_merge_tag_headers(parents, &tail);
1405 result = commit_tree_extended(msg, msg_len, tree, parents, ret,
1406 author, sign_commit, extra);
1407 free_commit_extra_headers(extra);
1408 return result;
1409 }
1410
1411 static int find_invalid_utf8(const char *buf, int len)
1412 {
1413 int offset = 0;
1414 static const unsigned int max_codepoint[] = {
1415 0x7f, 0x7ff, 0xffff, 0x10ffff
1416 };
1417
1418 while (len) {
1419 unsigned char c = *buf++;
1420 int bytes, bad_offset;
1421 unsigned int codepoint;
1422 unsigned int min_val, max_val;
1423
1424 len--;
1425 offset++;
1426
1427 /* Simple US-ASCII? No worries. */
1428 if (c < 0x80)
1429 continue;
1430
1431 bad_offset = offset-1;
1432
1433 /*
1434 * Count how many more high bits set: that's how
1435 * many more bytes this sequence should have.
1436 */
1437 bytes = 0;
1438 while (c & 0x40) {
1439 c <<= 1;
1440 bytes++;
1441 }
1442
1443 /*
1444 * Must be between 1 and 3 more bytes. Longer sequences result in
1445 * codepoints beyond U+10FFFF, which are guaranteed never to exist.
1446 */
1447 if (bytes < 1 || 3 < bytes)
1448 return bad_offset;
1449
1450 /* Do we *have* that many bytes? */
1451 if (len < bytes)
1452 return bad_offset;
1453
1454 /*
1455 * Place the encoded bits at the bottom of the value and compute the
1456 * valid range.
1457 */
1458 codepoint = (c & 0x7f) >> bytes;
1459 min_val = max_codepoint[bytes-1] + 1;
1460 max_val = max_codepoint[bytes];
1461
1462 offset += bytes;
1463 len -= bytes;
1464
1465 /* And verify that they are good continuation bytes */
1466 do {
1467 codepoint <<= 6;
1468 codepoint |= *buf & 0x3f;
1469 if ((*buf++ & 0xc0) != 0x80)
1470 return bad_offset;
1471 } while (--bytes);
1472
1473 /* Reject codepoints that are out of range for the sequence length. */
1474 if (codepoint < min_val || codepoint > max_val)
1475 return bad_offset;
1476 /* Surrogates are only for UTF-16 and cannot be encoded in UTF-8. */
1477 if ((codepoint & 0x1ff800) == 0xd800)
1478 return bad_offset;
1479 /* U+xxFFFE and U+xxFFFF are guaranteed non-characters. */
1480 if ((codepoint & 0xfffe) == 0xfffe)
1481 return bad_offset;
1482 /* So are anything in the range U+FDD0..U+FDEF. */
1483 if (codepoint >= 0xfdd0 && codepoint <= 0xfdef)
1484 return bad_offset;
1485 }
1486 return -1;
1487 }
1488
1489 /*
1490 * This verifies that the buffer is in proper utf8 format.
1491 *
1492 * If it isn't, it assumes any non-utf8 characters are Latin1,
1493 * and does the conversion.
1494 */
1495 static int verify_utf8(struct strbuf *buf)
1496 {
1497 int ok = 1;
1498 long pos = 0;
1499
1500 for (;;) {
1501 int bad;
1502 unsigned char c;
1503 unsigned char replace[2];
1504
1505 bad = find_invalid_utf8(buf->buf + pos, buf->len - pos);
1506 if (bad < 0)
1507 return ok;
1508 pos += bad;
1509 ok = 0;
1510 c = buf->buf[pos];
1511 strbuf_remove(buf, pos, 1);
1512
1513 /* We know 'c' must be in the range 128-255 */
1514 replace[0] = 0xc0 + (c >> 6);
1515 replace[1] = 0x80 + (c & 0x3f);
1516 strbuf_insert(buf, pos, replace, 2);
1517 pos += 2;
1518 }
1519 }
1520
1521 static const char commit_utf8_warn[] =
1522 "Warning: commit message did not conform to UTF-8.\n"
1523 "You may want to amend it after fixing the message, or set the config\n"
1524 "variable i18n.commitencoding to the encoding your project uses.\n";
1525
1526 int commit_tree_extended(const char *msg, size_t msg_len,
1527 const unsigned char *tree,
1528 struct commit_list *parents, unsigned char *ret,
1529 const char *author, const char *sign_commit,
1530 struct commit_extra_header *extra)
1531 {
1532 int result;
1533 int encoding_is_utf8;
1534 struct strbuf buffer;
1535
1536 assert_sha1_type(tree, OBJ_TREE);
1537
1538 if (memchr(msg, '\0', msg_len))
1539 return error("a NUL byte in commit log message not allowed.");
1540
1541 /* Not having i18n.commitencoding is the same as having utf-8 */
1542 encoding_is_utf8 = is_encoding_utf8(git_commit_encoding);
1543
1544 strbuf_init(&buffer, 8192); /* should avoid reallocs for the headers */
1545 strbuf_addf(&buffer, "tree %s\n", sha1_to_hex(tree));
1546
1547 /*
1548 * NOTE! This ordering means that the same exact tree merged with a
1549 * different order of parents will be a _different_ changeset even
1550 * if everything else stays the same.
1551 */
1552 while (parents) {
1553 struct commit_list *next = parents->next;
1554 struct commit *parent = parents->item;
1555
1556 strbuf_addf(&buffer, "parent %s\n",
1557 sha1_to_hex(parent->object.sha1));
1558 free(parents);
1559 parents = next;
1560 }
1561
1562 /* Person/date information */
1563 if (!author)
1564 author = git_author_info(IDENT_STRICT);
1565 strbuf_addf(&buffer, "author %s\n", author);
1566 strbuf_addf(&buffer, "committer %s\n", git_committer_info(IDENT_STRICT));
1567 if (!encoding_is_utf8)
1568 strbuf_addf(&buffer, "encoding %s\n", git_commit_encoding);
1569
1570 while (extra) {
1571 add_extra_header(&buffer, extra);
1572 extra = extra->next;
1573 }
1574 strbuf_addch(&buffer, '\n');
1575
1576 /* And add the comment */
1577 strbuf_add(&buffer, msg, msg_len);
1578
1579 /* And check the encoding */
1580 if (encoding_is_utf8 && !verify_utf8(&buffer))
1581 fprintf(stderr, commit_utf8_warn);
1582
1583 if (sign_commit && do_sign_commit(&buffer, sign_commit))
1584 return -1;
1585
1586 result = write_sha1_file(buffer.buf, buffer.len, commit_type, ret);
1587 strbuf_release(&buffer);
1588 return result;
1589 }
1590
1591 struct commit *get_merge_parent(const char *name)
1592 {
1593 struct object *obj;
1594 struct commit *commit;
1595 unsigned char sha1[20];
1596 if (get_sha1(name, sha1))
1597 return NULL;
1598 obj = parse_object(sha1);
1599 commit = (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
1600 if (commit && !commit->util) {
1601 struct merge_remote_desc *desc;
1602 desc = xmalloc(sizeof(*desc));
1603 desc->obj = obj;
1604 desc->name = strdup(name);
1605 commit->util = desc;
1606 }
1607 return commit;
1608 }
1609
1610 /*
1611 * Append a commit to the end of the commit_list.
1612 *
1613 * next starts by pointing to the variable that holds the head of an
1614 * empty commit_list, and is updated to point to the "next" field of
1615 * the last item on the list as new commits are appended.
1616 *
1617 * Usage example:
1618 *
1619 * struct commit_list *list;
1620 * struct commit_list **next = &list;
1621 *
1622 * next = commit_list_append(c1, next);
1623 * next = commit_list_append(c2, next);
1624 * assert(commit_list_count(list) == 2);
1625 * return list;
1626 */
1627 struct commit_list **commit_list_append(struct commit *commit,
1628 struct commit_list **next)
1629 {
1630 struct commit_list *new = xmalloc(sizeof(struct commit_list));
1631 new->item = commit;
1632 *next = new;
1633 new->next = NULL;
1634 return &new->next;
1635 }
1636
1637 void print_commit_list(struct commit_list *list,
1638 const char *format_cur,
1639 const char *format_last)
1640 {
1641 for ( ; list; list = list->next) {
1642 const char *format = list->next ? format_cur : format_last;
1643 printf(format, sha1_to_hex(list->item->object.sha1));
1644 }
1645 }