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"
12static struct commit_extra_header *read_commit_extra_header_lines(const char *buf, size_t len, const char **);
14int save_commit_buffer = 1;
16const char *commit_type = "commit";
18static int commit_count;
19static struct commit *check_commit(struct object *obj,
21 const unsigned char *sha1,
22 int quiet)
23{
24 if (obj->type != OBJ_COMMIT) {
25 if (!quiet)
26 error("Object %s is a %s, not a commit",
27 sha1_to_hex(sha1), typename(obj->type));
28 return NULL;
29 }
30 return (struct commit *) obj;
31}
32struct commit *lookup_commit_reference_gently(const unsigned char *sha1,
34 int quiet)
35{
36 struct object *obj = deref_tag(parse_object(sha1), NULL, 0);
37 if (!obj)
39 return NULL;
40 return check_commit(obj, sha1, quiet);
41}
42struct commit *lookup_commit_reference(const unsigned char *sha1)
44{
45 return lookup_commit_reference_gently(sha1, 0);
46}
47struct commit *lookup_commit_or_die(const unsigned char *sha1, const char *ref_name)
49{
50 struct commit *c = lookup_commit_reference(sha1);
51 if (!c)
52 die(_("could not parse %s"), ref_name);
53 if (hashcmp(sha1, c->object.sha1)) {
54 warning(_("%s %s is not a commit!"),
55 ref_name, sha1_to_hex(sha1));
56 }
57 return c;
58}
59struct commit *lookup_commit(const unsigned char *sha1)
61{
62 struct object *obj = lookup_object(sha1);
63 if (!obj) {
64 struct commit *c = alloc_commit_node();
65 c->index = commit_count++;
66 return create_object(sha1, OBJ_COMMIT, c);
67 }
68 if (!obj->type)
69 obj->type = OBJ_COMMIT;
70 return check_commit(obj, sha1, 0);
71}
72struct commit *lookup_commit_reference_by_name(const char *name)
74{
75 unsigned char sha1[20];
76 struct commit *commit;
77 if (get_sha1_committish(name, sha1))
79 return NULL;
80 commit = lookup_commit_reference(sha1);
81 if (!commit || parse_commit(commit))
82 return NULL;
83 return commit;
84}
85static unsigned long parse_commit_date(const char *buf, const char *tail)
87{
88 const char *dateptr;
89 if (buf + 6 >= tail)
91 return 0;
92 if (memcmp(buf, "author", 6))
93 return 0;
94 while (buf < tail && *buf++ != '\n')
95 /* nada */;
96 if (buf + 9 >= tail)
97 return 0;
98 if (memcmp(buf, "committer", 9))
99 return 0;
100 while (buf < tail && *buf++ != '>')
101 /* nada */;
102 if (buf >= tail)
103 return 0;
104 dateptr = buf;
105 while (buf < tail && *buf++ != '\n')
106 /* nada */;
107 if (buf >= tail)
108 return 0;
109 /* dateptr < buf && buf[-1] == '\n', so strtoul will stop at buf-1 */
110 return strtoul(dateptr, NULL, 10);
111}
112static struct commit_graft **commit_graft;
114static int commit_graft_alloc, commit_graft_nr;
115static int commit_graft_pos(const unsigned char *sha1)
117{
118 int lo, hi;
119 lo = 0;
120 hi = commit_graft_nr;
121 while (lo < hi) {
122 int mi = (lo + hi) / 2;
123 struct commit_graft *graft = commit_graft[mi];
124 int cmp = hashcmp(sha1, graft->sha1);
125 if (!cmp)
126 return mi;
127 if (cmp < 0)
128 hi = mi;
129 else
130 lo = mi + 1;
131 }
132 return -lo - 1;
133}
134int register_commit_graft(struct commit_graft *graft, int ignore_dups)
136{
137 int pos = commit_graft_pos(graft->sha1);
138 if (0 <= pos) {
140 if (ignore_dups)
141 free(graft);
142 else {
143 free(commit_graft[pos]);
144 commit_graft[pos] = graft;
145 }
146 return 1;
147 }
148 pos = -pos - 1;
149 if (commit_graft_alloc <= ++commit_graft_nr) {
150 commit_graft_alloc = alloc_nr(commit_graft_alloc);
151 commit_graft = xrealloc(commit_graft,
152 sizeof(*commit_graft) *
153 commit_graft_alloc);
154 }
155 if (pos < commit_graft_nr)
156 memmove(commit_graft + pos + 1,
157 commit_graft + pos,
158 (commit_graft_nr - pos - 1) *
159 sizeof(*commit_graft));
160 commit_graft[pos] = graft;
161 return 0;
162}
163struct commit_graft *read_graft_line(char *buf, int len)
165{
166 /* The format is just "Commit Parent1 Parent2 ...\n" */
167 int i;
168 struct commit_graft *graft = NULL;
169 while (len && isspace(buf[len-1]))
171 buf[--len] = '\0';
172 if (buf[0] == '#' || buf[0] == '\0')
173 return NULL;
174 if ((len + 1) % 41)
175 goto bad_graft_data;
176 i = (len + 1) / 41 - 1;
177 graft = xmalloc(sizeof(*graft) + 20 * i);
178 graft->nr_parent = i;
179 if (get_sha1_hex(buf, graft->sha1))
180 goto bad_graft_data;
181 for (i = 40; i < len; i += 41) {
182 if (buf[i] != ' ')
183 goto bad_graft_data;
184 if (get_sha1_hex(buf + i + 1, graft->parent[i/41]))
185 goto bad_graft_data;
186 }
187 return graft;
188bad_graft_data:
190 error("bad graft data: %s", buf);
191 free(graft);
192 return NULL;
193}
194static int read_graft_file(const char *graft_file)
196{
197 FILE *fp = fopen(graft_file, "r");
198 char buf[1024];
199 if (!fp)
200 return -1;
201 while (fgets(buf, sizeof(buf), fp)) {
202 /* The format is just "Commit Parent1 Parent2 ...\n" */
203 int len = strlen(buf);
204 struct commit_graft *graft = read_graft_line(buf, len);
205 if (!graft)
206 continue;
207 if (register_commit_graft(graft, 1))
208 error("duplicate graft data: %s", buf);
209 }
210 fclose(fp);
211 return 0;
212}
213static void prepare_commit_graft(void)
215{
216 static int commit_graft_prepared;
217 char *graft_file;
218 if (commit_graft_prepared)
220 return;
221 graft_file = get_graft_file();
222 read_graft_file(graft_file);
223 /* make sure shallows are read */
224 is_repository_shallow();
225 commit_graft_prepared = 1;
226}
227struct commit_graft *lookup_commit_graft(const unsigned char *sha1)
229{
230 int pos;
231 prepare_commit_graft();
232 pos = commit_graft_pos(sha1);
233 if (pos < 0)
234 return NULL;
235 return commit_graft[pos];
236}
237int for_each_commit_graft(each_commit_graft_fn fn, void *cb_data)
239{
240 int i, ret;
241 for (i = ret = 0; i < commit_graft_nr && !ret; i++)
242 ret = fn(commit_graft[i], cb_data);
243 return ret;
244}
245int unregister_shallow(const unsigned char *sha1)
247{
248 int pos = commit_graft_pos(sha1);
249 if (pos < 0)
250 return -1;
251 if (pos + 1 < commit_graft_nr)
252 memmove(commit_graft + pos, commit_graft + pos + 1,
253 sizeof(struct commit_graft *)
254 * (commit_graft_nr - pos - 1));
255 commit_graft_nr--;
256 return 0;
257}
258int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long size)
260{
261 const char *tail = buffer;
262 const char *bufptr = buffer;
263 unsigned char parent[20];
264 struct commit_list **pptr;
265 struct commit_graft *graft;
266 if (item->object.parsed)
268 return 0;
269 item->object.parsed = 1;
270 tail += size;
271 if (tail <= bufptr + 46 || memcmp(bufptr, "tree ", 5) || bufptr[45] != '\n')
272 return error("bogus commit object %s", sha1_to_hex(item->object.sha1));
273 if (get_sha1_hex(bufptr + 5, parent) < 0)
274 return error("bad tree pointer in commit %s",
275 sha1_to_hex(item->object.sha1));
276 item->tree = lookup_tree(parent);
277 bufptr += 46; /* "tree " + "hex sha1" + "\n" */
278 pptr = &item->parents;
279 graft = lookup_commit_graft(item->object.sha1);
281 while (bufptr + 48 < tail && !memcmp(bufptr, "parent ", 7)) {
282 struct commit *new_parent;
283 if (tail <= bufptr + 48 ||
285 get_sha1_hex(bufptr + 7, parent) ||
286 bufptr[47] != '\n')
287 return error("bad parents in commit %s", sha1_to_hex(item->object.sha1));
288 bufptr += 48;
289 /*
290 * The clone is shallow if nr_parent < 0, and we must
291 * not traverse its real parents even when we unhide them.
292 */
293 if (graft && (graft->nr_parent < 0 || grafts_replace_parents))
294 continue;
295 new_parent = lookup_commit(parent);
296 if (new_parent)
297 pptr = &commit_list_insert(new_parent, pptr)->next;
298 }
299 if (graft) {
300 int i;
301 struct commit *new_parent;
302 for (i = 0; i < graft->nr_parent; i++) {
303 new_parent = lookup_commit(graft->parent[i]);
304 if (!new_parent)
305 continue;
306 pptr = &commit_list_insert(new_parent, pptr)->next;
307 }
308 }
309 item->date = parse_commit_date(bufptr, tail);
310 return 0;
312}
313int parse_commit(struct commit *item)
315{
316 enum object_type type;
317 void *buffer;
318 unsigned long size;
319 int ret;
320 if (!item)
322 return -1;
323 if (item->object.parsed)
324 return 0;
325 buffer = read_sha1_file(item->object.sha1, &type, &size);
326 if (!buffer)
327 return error("Could not read %s",
328 sha1_to_hex(item->object.sha1));
329 if (type != OBJ_COMMIT) {
330 free(buffer);
331 return error("Object %s not a commit",
332 sha1_to_hex(item->object.sha1));
333 }
334 ret = parse_commit_buffer(item, buffer, size);
335 if (save_commit_buffer && !ret) {
336 item->buffer = buffer;
337 return 0;
338 }
339 free(buffer);
340 return ret;
341}
342int find_commit_subject(const char *commit_buffer, const char **subject)
344{
345 const char *eol;
346 const char *p = commit_buffer;
347 while (*p && (*p != '\n' || p[1] != '\n'))
349 p++;
350 if (*p) {
351 p += 2;
352 for (eol = p; *eol && *eol != '\n'; eol++)
353 ; /* do nothing */
354 } else
355 eol = p;
356 *subject = p;
358 return eol - p;
360}
361struct commit_list *commit_list_insert(struct commit *item, struct commit_list **list_p)
363{
364 struct commit_list *new_list = xmalloc(sizeof(struct commit_list));
365 new_list->item = item;
366 new_list->next = *list_p;
367 *list_p = new_list;
368 return new_list;
369}
370unsigned commit_list_count(const struct commit_list *l)
372{
373 unsigned c = 0;
374 for (; l; l = l->next )
375 c++;
376 return c;
377}
378void free_commit_list(struct commit_list *list)
380{
381 while (list) {
382 struct commit_list *temp = list;
383 list = temp->next;
384 free(temp);
385 }
386}
387struct commit_list * commit_list_insert_by_date(struct commit *item, struct commit_list **list)
389{
390 struct commit_list **pp = list;
391 struct commit_list *p;
392 while ((p = *pp) != NULL) {
393 if (p->item->date < item->date) {
394 break;
395 }
396 pp = &p->next;
397 }
398 return commit_list_insert(item, pp);
399}
400static int commit_list_compare_by_date(const void *a, const void *b)
402{
403 unsigned long a_date = ((const struct commit_list *)a)->item->date;
404 unsigned long b_date = ((const struct commit_list *)b)->item->date;
405 if (a_date < b_date)
406 return 1;
407 if (a_date > b_date)
408 return -1;
409 return 0;
410}
411static void *commit_list_get_next(const void *a)
413{
414 return ((const struct commit_list *)a)->next;
415}
416static void commit_list_set_next(void *a, void *next)
418{
419 ((struct commit_list *)a)->next = next;
420}
421void commit_list_sort_by_date(struct commit_list **list)
423{
424 *list = llist_mergesort(*list, commit_list_get_next, commit_list_set_next,
425 commit_list_compare_by_date);
426}
427struct commit *pop_most_recent_commit(struct commit_list **list,
429 unsigned int mark)
430{
431 struct commit *ret = (*list)->item;
432 struct commit_list *parents = ret->parents;
433 struct commit_list *old = *list;
434 *list = (*list)->next;
436 free(old);
437 while (parents) {
439 struct commit *commit = parents->item;
440 if (!parse_commit(commit) && !(commit->object.flags & mark)) {
441 commit->object.flags |= mark;
442 commit_list_insert_by_date(commit, list);
443 }
444 parents = parents->next;
445 }
446 return ret;
447}
448static void clear_commit_marks_1(struct commit_list **plist,
450 struct commit *commit, unsigned int mark)
451{
452 while (commit) {
453 struct commit_list *parents;
454 if (!(mark & commit->object.flags))
456 return;
457 commit->object.flags &= ~mark;
459 parents = commit->parents;
461 if (!parents)
462 return;
463 while ((parents = parents->next))
465 commit_list_insert(parents->item, plist);
466 commit = commit->parents->item;
468 }
469}
470void clear_commit_marks(struct commit *commit, unsigned int mark)
472{
473 struct commit_list *list = NULL;
474 commit_list_insert(commit, &list);
475 while (list)
476 clear_commit_marks_1(&list, pop_commit(&list), mark);
477}
478void clear_commit_marks_for_object_array(struct object_array *a, unsigned mark)
480{
481 struct object *object;
482 struct commit *commit;
483 unsigned int i;
484 for (i = 0; i < a->nr; i++) {
486 object = a->objects[i].item;
487 commit = lookup_commit_reference_gently(object->sha1, 1);
488 if (commit)
489 clear_commit_marks(commit, mark);
490 }
491}
492struct commit *pop_commit(struct commit_list **stack)
494{
495 struct commit_list *top = *stack;
496 struct commit *item = top ? top->item : NULL;
497 if (top) {
499 *stack = top->next;
500 free(top);
501 }
502 return item;
503}
504/*
506 * Topological sort support
507 */
508/* count number of children that have not been emitted */
510define_commit_slab(indegree_slab, int);
511/*
513 * Performs an in-place topological sort on the list supplied.
514 */
515void sort_in_topological_order(struct commit_list ** list, enum rev_sort_order sort_order)
516{
517 struct commit_list *next, *orig = *list;
518 struct commit_list *work, **insert;
519 struct commit_list **pptr;
520 struct indegree_slab indegree;
521 if (!orig)
523 return;
524 *list = NULL;
525 init_indegree_slab(&indegree);
527 /* Mark them and clear the indegree */
529 for (next = orig; next; next = next->next) {
530 struct commit *commit = next->item;
531 *(indegree_slab_at(&indegree, commit)) = 1;
532 }
533 /* update the indegree */
535 for (next = orig; next; next = next->next) {
536 struct commit_list * parents = next->item->parents;
537 while (parents) {
538 struct commit *parent = parents->item;
539 int *pi = indegree_slab_at(&indegree, parent);
540 if (*pi)
542 (*pi)++;
543 parents = parents->next;
544 }
545 }
546 /*
548 * find the tips
549 *
550 * tips are nodes not reachable from any other node in the list
551 *
552 * the tips serve as a starting set for the work queue.
553 */
554 work = NULL;
555 insert = &work;
556 for (next = orig; next; next = next->next) {
557 struct commit *commit = next->item;
558 if (*(indegree_slab_at(&indegree, commit)) == 1)
560 insert = &commit_list_insert(commit, insert)->next;
561 }
562 /* process the list in topological order */
564 if (sort_order != REV_SORT_IN_GRAPH_ORDER)
565 commit_list_sort_by_date(&work);
566 pptr = list;
568 *list = NULL;
569 while (work) {
570 struct commit *commit;
571 struct commit_list *parents, *work_item;
572 work_item = work;
574 work = work_item->next;
575 work_item->next = NULL;
576 commit = work_item->item;
578 for (parents = commit->parents; parents ; parents = parents->next) {
579 struct commit *parent = parents->item;
580 int *pi = indegree_slab_at(&indegree, parent);
581 if (!*pi)
583 continue;
584 /*
586 * parents are only enqueued for emission
587 * when all their children have been emitted thereby
588 * guaranteeing topological order.
589 */
590 if (--(*pi) == 1) {
591 switch (sort_order) {
592 case REV_SORT_BY_COMMIT_DATE:
593 commit_list_insert_by_date(parent, &work);
594 break;
595 default: /* REV_SORT_IN_GRAPH_ORDER */
596 commit_list_insert(parent, &work);
597 break;
598 }
599 }
600 }
601 /*
602 * work_item is a commit all of whose children
603 * have already been emitted. we can emit it now.
604 */
605 *(indegree_slab_at(&indegree, commit)) = 0;
606 *pptr = work_item;
607 pptr = &work_item->next;
608 }
609 clear_indegree_slab(&indegree);
611}
612/* merge-base stuff */
614/* bits #0..15 in revision.h */
616#define PARENT1 (1u<<16)
617#define PARENT2 (1u<<17)
618#define STALE (1u<<18)
619#define RESULT (1u<<19)
620static const unsigned all_flags = (PARENT1 | PARENT2 | STALE | RESULT);
622static struct commit *interesting(struct commit_list *list)
624{
625 while (list) {
626 struct commit *commit = list->item;
627 list = list->next;
628 if (commit->object.flags & STALE)
629 continue;
630 return commit;
631 }
632 return NULL;
633}
634/* all input commits in one and twos[] must have been parsed! */
636static struct commit_list *paint_down_to_common(struct commit *one, int n, struct commit **twos)
637{
638 struct commit_list *list = NULL;
639 struct commit_list *result = NULL;
640 int i;
641 one->object.flags |= PARENT1;
643 commit_list_insert_by_date(one, &list);
644 if (!n)
645 return list;
646 for (i = 0; i < n; i++) {
647 twos[i]->object.flags |= PARENT2;
648 commit_list_insert_by_date(twos[i], &list);
649 }
650 while (interesting(list)) {
652 struct commit *commit;
653 struct commit_list *parents;
654 struct commit_list *next;
655 int flags;
656 commit = list->item;
658 next = list->next;
659 free(list);
660 list = next;
661 flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
663 if (flags == (PARENT1 | PARENT2)) {
664 if (!(commit->object.flags & RESULT)) {
665 commit->object.flags |= RESULT;
666 commit_list_insert_by_date(commit, &result);
667 }
668 /* Mark parents of a found merge stale */
669 flags |= STALE;
670 }
671 parents = commit->parents;
672 while (parents) {
673 struct commit *p = parents->item;
674 parents = parents->next;
675 if ((p->object.flags & flags) == flags)
676 continue;
677 if (parse_commit(p))
678 return NULL;
679 p->object.flags |= flags;
680 commit_list_insert_by_date(p, &list);
681 }
682 }
683 free_commit_list(list);
685 return result;
686}
687static struct commit_list *merge_bases_many(struct commit *one, int n, struct commit **twos)
689{
690 struct commit_list *list = NULL;
691 struct commit_list *result = NULL;
692 int i;
693 for (i = 0; i < n; i++) {
695 if (one == twos[i])
696 /*
697 * We do not mark this even with RESULT so we do not
698 * have to clean it up.
699 */
700 return commit_list_insert(one, &result);
701 }
702 if (parse_commit(one))
704 return NULL;
705 for (i = 0; i < n; i++) {
706 if (parse_commit(twos[i]))
707 return NULL;
708 }
709 list = paint_down_to_common(one, n, twos);
711 while (list) {
713 struct commit_list *next = list->next;
714 if (!(list->item->object.flags & STALE))
715 commit_list_insert_by_date(list->item, &result);
716 free(list);
717 list = next;
718 }
719 return result;
720}
721struct commit_list *get_octopus_merge_bases(struct commit_list *in)
723{
724 struct commit_list *i, *j, *k, *ret = NULL;
725 struct commit_list **pptr = &ret;
726 for (i = in; i; i = i->next) {
728 if (!ret)
729 pptr = &commit_list_insert(i->item, pptr)->next;
730 else {
731 struct commit_list *new = NULL, *end = NULL;
732 for (j = ret; j; j = j->next) {
734 struct commit_list *bases;
735 bases = get_merge_bases(i->item, j->item, 1);
736 if (!new)
737 new = bases;
738 else
739 end->next = bases;
740 for (k = bases; k; k = k->next)
741 end = k;
742 }
743 ret = new;
744 }
745 }
746 return ret;
747}
748static int remove_redundant(struct commit **array, int cnt)
750{
751 /*
752 * Some commit in the array may be an ancestor of
753 * another commit. Move such commit to the end of
754 * the array, and return the number of commits that
755 * are independent from each other.
756 */
757 struct commit **work;
758 unsigned char *redundant;
759 int *filled_index;
760 int i, j, filled;
761 work = xcalloc(cnt, sizeof(*work));
763 redundant = xcalloc(cnt, 1);
764 filled_index = xmalloc(sizeof(*filled_index) * (cnt - 1));
765 for (i = 0; i < cnt; i++)
767 parse_commit(array[i]);
768 for (i = 0; i < cnt; i++) {
769 struct commit_list *common;
770 if (redundant[i])
772 continue;
773 for (j = filled = 0; j < cnt; j++) {
774 if (i == j || redundant[j])
775 continue;
776 filled_index[filled] = j;
777 work[filled++] = array[j];
778 }
779 common = paint_down_to_common(array[i], filled, work);
780 if (array[i]->object.flags & PARENT2)
781 redundant[i] = 1;
782 for (j = 0; j < filled; j++)
783 if (work[j]->object.flags & PARENT1)
784 redundant[filled_index[j]] = 1;
785 clear_commit_marks(array[i], all_flags);
786 for (j = 0; j < filled; j++)
787 clear_commit_marks(work[j], all_flags);
788 free_commit_list(common);
789 }
790 /* Now collect the result */
792 memcpy(work, array, sizeof(*array) * cnt);
793 for (i = filled = 0; i < cnt; i++)
794 if (!redundant[i])
795 array[filled++] = work[i];
796 for (j = filled, i = 0; i < cnt; i++)
797 if (redundant[i])
798 array[j++] = work[i];
799 free(work);
800 free(redundant);
801 free(filled_index);
802 return filled;
803}
804struct commit_list *get_merge_bases_many(struct commit *one,
806 int n,
807 struct commit **twos,
808 int cleanup)
809{
810 struct commit_list *list;
811 struct commit **rslt;
812 struct commit_list *result;
813 int cnt, i;
814 result = merge_bases_many(one, n, twos);
816 for (i = 0; i < n; i++) {
817 if (one == twos[i])
818 return result;
819 }
820 if (!result || !result->next) {
821 if (cleanup) {
822 clear_commit_marks(one, all_flags);
823 for (i = 0; i < n; i++)
824 clear_commit_marks(twos[i], all_flags);
825 }
826 return result;
827 }
828 /* There are more than one */
830 cnt = 0;
831 list = result;
832 while (list) {
833 list = list->next;
834 cnt++;
835 }
836 rslt = xcalloc(cnt, sizeof(*rslt));
837 for (list = result, i = 0; list; list = list->next)
838 rslt[i++] = list->item;
839 free_commit_list(result);
840 clear_commit_marks(one, all_flags);
842 for (i = 0; i < n; i++)
843 clear_commit_marks(twos[i], all_flags);
844 cnt = remove_redundant(rslt, cnt);
846 result = NULL;
847 for (i = 0; i < cnt; i++)
848 commit_list_insert_by_date(rslt[i], &result);
849 free(rslt);
850 return result;
851}
852struct commit_list *get_merge_bases(struct commit *one, struct commit *two,
854 int cleanup)
855{
856 return get_merge_bases_many(one, 1, &two, cleanup);
857}
858/*
860 * Is "commit" a descendant of one of the elements on the "with_commit" list?
861 */
862int is_descendant_of(struct commit *commit, struct commit_list *with_commit)
863{
864 if (!with_commit)
865 return 1;
866 while (with_commit) {
867 struct commit *other;
868 other = with_commit->item;
870 with_commit = with_commit->next;
871 if (in_merge_bases(other, commit))
872 return 1;
873 }
874 return 0;
875}
876/*
878 * Is "commit" an ancestor of (i.e. reachable from) the "reference"?
879 */
880int in_merge_bases(struct commit *commit, struct commit *reference)
881{
882 struct commit_list *bases;
883 int ret = 0;
884 if (parse_commit(commit) || parse_commit(reference))
886 return ret;
887 bases = paint_down_to_common(commit, 1, &reference);
889 if (commit->object.flags & PARENT2)
890 ret = 1;
891 clear_commit_marks(commit, all_flags);
892 clear_commit_marks(reference, all_flags);
893 free_commit_list(bases);
894 return ret;
895}
896struct commit_list *reduce_heads(struct commit_list *heads)
898{
899 struct commit_list *p;
900 struct commit_list *result = NULL, **tail = &result;
901 struct commit **array;
902 int num_head, i;
903 if (!heads)
905 return NULL;
906 /* Uniquify */
908 for (p = heads; p; p = p->next)
909 p->item->object.flags &= ~STALE;
910 for (p = heads, num_head = 0; p; p = p->next) {
911 if (p->item->object.flags & STALE)
912 continue;
913 p->item->object.flags |= STALE;
914 num_head++;
915 }
916 array = xcalloc(sizeof(*array), num_head);
917 for (p = heads, i = 0; p; p = p->next) {
918 if (p->item->object.flags & STALE) {
919 array[i++] = p->item;
920 p->item->object.flags &= ~STALE;
921 }
922 }
923 num_head = remove_redundant(array, num_head);
924 for (i = 0; i < num_head; i++)
925 tail = &commit_list_insert(array[i], tail)->next;
926 return result;
927}
928static const char gpg_sig_header[] = "gpgsig";
930static const int gpg_sig_header_len = sizeof(gpg_sig_header) - 1;
931static int do_sign_commit(struct strbuf *buf, const char *keyid)
933{
934 struct strbuf sig = STRBUF_INIT;
935 int inspos, copypos;
936 /* find the end of the header */
938 inspos = strstr(buf->buf, "\n\n") - buf->buf + 1;
939 if (!keyid || !*keyid)
941 keyid = get_signing_key();
942 if (sign_buffer(buf, &sig, keyid)) {
943 strbuf_release(&sig);
944 return -1;
945 }
946 for (copypos = 0; sig.buf[copypos]; ) {
948 const char *bol = sig.buf + copypos;
949 const char *eol = strchrnul(bol, '\n');
950 int len = (eol - bol) + !!*eol;
951 if (!copypos) {
953 strbuf_insert(buf, inspos, gpg_sig_header, gpg_sig_header_len);
954 inspos += gpg_sig_header_len;
955 }
956 strbuf_insert(buf, inspos++, " ", 1);
957 strbuf_insert(buf, inspos, bol, len);
958 inspos += len;
959 copypos += len;
960 }
961 strbuf_release(&sig);
962 return 0;
963}
964int parse_signed_commit(const unsigned char *sha1,
966 struct strbuf *payload, struct strbuf *signature)
967{
968 unsigned long size;
969 enum object_type type;
970 char *buffer = read_sha1_file(sha1, &type, &size);
971 int in_signature, saw_signature = -1;
972 char *line, *tail;
973 if (!buffer || type != OBJ_COMMIT)
975 goto cleanup;
976 line = buffer;
978 tail = buffer + size;
979 in_signature = 0;
980 saw_signature = 0;
981 while (line < tail) {
982 const char *sig = NULL;
983 char *next = memchr(line, '\n', tail - line);
984 next = next ? next + 1 : tail;
986 if (in_signature && line[0] == ' ')
987 sig = line + 1;
988 else if (!prefixcmp(line, gpg_sig_header) &&
989 line[gpg_sig_header_len] == ' ')
990 sig = line + gpg_sig_header_len + 1;
991 if (sig) {
992 strbuf_add(signature, sig, next - sig);
993 saw_signature = 1;
994 in_signature = 1;
995 } else {
996 if (*line == '\n')
997 /* dump the whole remainder of the buffer */
998 next = tail;
999 strbuf_add(payload, line, next - line);
1000 in_signature = 0;
1001 }
1002 line = next;
1003 }
1004 cleanup:
1005 free(buffer);
1006 return saw_signature;
1007}
1008static void handle_signed_tag(struct commit *parent, struct commit_extra_header ***tail)
1010{
1011 struct merge_remote_desc *desc;
1012 struct commit_extra_header *mergetag;
1013 char *buf;
1014 unsigned long size, len;
1015 enum object_type type;
1016 desc = merge_remote_util(parent);
1018 if (!desc || !desc->obj)
1019 return;
1020 buf = read_sha1_file(desc->obj->sha1, &type, &size);
1021 if (!buf || type != OBJ_TAG)
1022 goto free_return;
1023 len = parse_signature(buf, size);
1024 if (size == len)
1025 goto free_return;
1026 /*
1027 * We could verify this signature and either omit the tag when
1028 * it does not validate, but the integrator may not have the
1029 * public key of the signer of the tag he is merging, while a
1030 * later auditor may have it while auditing, so let's not run
1031 * verify-signed-buffer here for now...
1032 *
1033 * if (verify_signed_buffer(buf, len, buf + len, size - len, ...))
1034 * warn("warning: signed tag unverified.");
1035 */
1036 mergetag = xcalloc(1, sizeof(*mergetag));
1037 mergetag->key = xstrdup("mergetag");
1038 mergetag->value = buf;
1039 mergetag->len = size;
1040 **tail = mergetag;
1042 *tail = &mergetag->next;
1043 return;
1044free_return:
1046 free(buf);
1047}
1048void append_merge_tag_headers(struct commit_list *parents,
1050 struct commit_extra_header ***tail)
1051{
1052 while (parents) {
1053 struct commit *parent = parents->item;
1054 handle_signed_tag(parent, tail);
1055 parents = parents->next;
1056 }
1057}
1058static void add_extra_header(struct strbuf *buffer,
1060 struct commit_extra_header *extra)
1061{
1062 strbuf_addstr(buffer, extra->key);
1063 if (extra->len)
1064 strbuf_add_lines(buffer, " ", extra->value, extra->len);
1065 else
1066 strbuf_addch(buffer, '\n');
1067}
1068struct commit_extra_header *read_commit_extra_headers(struct commit *commit,
1070 const char **exclude)
1071{
1072 struct commit_extra_header *extra = NULL;
1073 unsigned long size;
1074 enum object_type type;
1075 char *buffer = read_sha1_file(commit->object.sha1, &type, &size);
1076 if (buffer && type == OBJ_COMMIT)
1077 extra = read_commit_extra_header_lines(buffer, size, exclude);
1078 free(buffer);
1079 return extra;
1080}
1081static inline int standard_header_field(const char *field, size_t len)
1083{
1084 return ((len == 4 && !memcmp(field, "tree ", 5)) ||
1085 (len == 6 && !memcmp(field, "parent ", 7)) ||
1086 (len == 6 && !memcmp(field, "author ", 7)) ||
1087 (len == 9 && !memcmp(field, "committer ", 10)) ||
1088 (len == 8 && !memcmp(field, "encoding ", 9)));
1089}
1090static int excluded_header_field(const char *field, size_t len, const char **exclude)
1092{
1093 if (!exclude)
1094 return 0;
1095 while (*exclude) {
1097 size_t xlen = strlen(*exclude);
1098 if (len == xlen &&
1099 !memcmp(field, *exclude, xlen) && field[xlen] == ' ')
1100 return 1;
1101 exclude++;
1102 }
1103 return 0;
1104}
1105static struct commit_extra_header *read_commit_extra_header_lines(
1107 const char *buffer, size_t size,
1108 const char **exclude)
1109{
1110 struct commit_extra_header *extra = NULL, **tail = &extra, *it = NULL;
1111 const char *line, *next, *eof, *eob;
1112 struct strbuf buf = STRBUF_INIT;
1113 for (line = buffer, eob = line + size;
1115 line < eob && *line != '\n';
1116 line = next) {
1117 next = memchr(line, '\n', eob - line);
1118 next = next ? next + 1 : eob;
1119 if (*line == ' ') {
1120 /* continuation */
1121 if (it)
1122 strbuf_add(&buf, line + 1, next - (line + 1));
1123 continue;
1124 }
1125 if (it)
1126 it->value = strbuf_detach(&buf, &it->len);
1127 strbuf_reset(&buf);
1128 it = NULL;
1129 eof = strchr(line, ' ');
1131 if (next <= eof)
1132 eof = next;
1133 if (standard_header_field(line, eof - line) ||
1135 excluded_header_field(line, eof - line, exclude))
1136 continue;
1137 it = xcalloc(1, sizeof(*it));
1139 it->key = xmemdupz(line, eof-line);
1140 *tail = it;
1141 tail = &it->next;
1142 if (eof + 1 < next)
1143 strbuf_add(&buf, eof + 1, next - (eof + 1));
1144 }
1145 if (it)
1146 it->value = strbuf_detach(&buf, &it->len);
1147 return extra;
1148}
1149void free_commit_extra_headers(struct commit_extra_header *extra)
1151{
1152 while (extra) {
1153 struct commit_extra_header *next = extra->next;
1154 free(extra->key);
1155 free(extra->value);
1156 free(extra);
1157 extra = next;
1158 }
1159}
1160int commit_tree(const struct strbuf *msg, unsigned char *tree,
1162 struct commit_list *parents, unsigned char *ret,
1163 const char *author, const char *sign_commit)
1164{
1165 struct commit_extra_header *extra = NULL, **tail = &extra;
1166 int result;
1167 append_merge_tag_headers(parents, &tail);
1169 result = commit_tree_extended(msg, tree, parents, ret,
1170 author, sign_commit, extra);
1171 free_commit_extra_headers(extra);
1172 return result;
1173}
1174static int find_invalid_utf8(const char *buf, int len)
1176{
1177 int offset = 0;
1178 while (len) {
1180 unsigned char c = *buf++;
1181 int bytes, bad_offset;
1182 len--;
1184 offset++;
1185 /* Simple US-ASCII? No worries. */
1187 if (c < 0x80)
1188 continue;
1189 bad_offset = offset-1;
1191 /*
1193 * Count how many more high bits set: that's how
1194 * many more bytes this sequence should have.
1195 */
1196 bytes = 0;
1197 while (c & 0x40) {
1198 c <<= 1;
1199 bytes++;
1200 }
1201 /* Must be between 1 and 5 more bytes */
1203 if (bytes < 1 || bytes > 5)
1204 return bad_offset;
1205 /* Do we *have* that many bytes? */
1207 if (len < bytes)
1208 return bad_offset;
1209 offset += bytes;
1211 len -= bytes;
1212 /* And verify that they are good continuation bytes */
1214 do {
1215 if ((*buf++ & 0xc0) != 0x80)
1216 return bad_offset;
1217 } while (--bytes);
1218 /* We could/should check the value and length here too */
1220 }
1221 return -1;
1222}
1223/*
1225 * This verifies that the buffer is in proper utf8 format.
1226 *
1227 * If it isn't, it assumes any non-utf8 characters are Latin1,
1228 * and does the conversion.
1229 *
1230 * Fixme: we should probably also disallow overlong forms and
1231 * invalid characters. But we don't do that currently.
1232 */
1233static int verify_utf8(struct strbuf *buf)
1234{
1235 int ok = 1;
1236 long pos = 0;
1237 for (;;) {
1239 int bad;
1240 unsigned char c;
1241 unsigned char replace[2];
1242 bad = find_invalid_utf8(buf->buf + pos, buf->len - pos);
1244 if (bad < 0)
1245 return ok;
1246 pos += bad;
1247 ok = 0;
1248 c = buf->buf[pos];
1249 strbuf_remove(buf, pos, 1);
1250 /* We know 'c' must be in the range 128-255 */
1252 replace[0] = 0xc0 + (c >> 6);
1253 replace[1] = 0x80 + (c & 0x3f);
1254 strbuf_insert(buf, pos, replace, 2);
1255 pos += 2;
1256 }
1257}
1258static const char commit_utf8_warn[] =
1260"Warning: commit message did not conform to UTF-8.\n"
1261"You may want to amend it after fixing the message, or set the config\n"
1262"variable i18n.commitencoding to the encoding your project uses.\n";
1263int commit_tree_extended(const struct strbuf *msg, unsigned char *tree,
1265 struct commit_list *parents, unsigned char *ret,
1266 const char *author, const char *sign_commit,
1267 struct commit_extra_header *extra)
1268{
1269 int result;
1270 int encoding_is_utf8;
1271 struct strbuf buffer;
1272 assert_sha1_type(tree, OBJ_TREE);
1274 if (memchr(msg->buf, '\0', msg->len))
1276 return error("a NUL byte in commit log message not allowed.");
1277 /* Not having i18n.commitencoding is the same as having utf-8 */
1279 encoding_is_utf8 = is_encoding_utf8(git_commit_encoding);
1280 strbuf_init(&buffer, 8192); /* should avoid reallocs for the headers */
1282 strbuf_addf(&buffer, "tree %s\n", sha1_to_hex(tree));
1283 /*
1285 * NOTE! This ordering means that the same exact tree merged with a
1286 * different order of parents will be a _different_ changeset even
1287 * if everything else stays the same.
1288 */
1289 while (parents) {
1290 struct commit_list *next = parents->next;
1291 struct commit *parent = parents->item;
1292 strbuf_addf(&buffer, "parent %s\n",
1294 sha1_to_hex(parent->object.sha1));
1295 free(parents);
1296 parents = next;
1297 }
1298 /* Person/date information */
1300 if (!author)
1301 author = git_author_info(IDENT_STRICT);
1302 strbuf_addf(&buffer, "author %s\n", author);
1303 strbuf_addf(&buffer, "committer %s\n", git_committer_info(IDENT_STRICT));
1304 if (!encoding_is_utf8)
1305 strbuf_addf(&buffer, "encoding %s\n", git_commit_encoding);
1306 while (extra) {
1308 add_extra_header(&buffer, extra);
1309 extra = extra->next;
1310 }
1311 strbuf_addch(&buffer, '\n');
1312 /* And add the comment */
1314 strbuf_addbuf(&buffer, msg);
1315 /* And check the encoding */
1317 if (encoding_is_utf8 && !verify_utf8(&buffer))
1318 fprintf(stderr, commit_utf8_warn);
1319 if (sign_commit && do_sign_commit(&buffer, sign_commit))
1321 return -1;
1322 result = write_sha1_file(buffer.buf, buffer.len, commit_type, ret);
1324 strbuf_release(&buffer);
1325 return result;
1326}
1327struct commit *get_merge_parent(const char *name)
1329{
1330 struct object *obj;
1331 struct commit *commit;
1332 unsigned char sha1[20];
1333 if (get_sha1(name, sha1))
1334 return NULL;
1335 obj = parse_object(sha1);
1336 commit = (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
1337 if (commit && !commit->util) {
1338 struct merge_remote_desc *desc;
1339 desc = xmalloc(sizeof(*desc));
1340 desc->obj = obj;
1341 desc->name = strdup(name);
1342 commit->util = desc;
1343 }
1344 return commit;
1345}
1346/*
1348 * Append a commit to the end of the commit_list.
1349 *
1350 * next starts by pointing to the variable that holds the head of an
1351 * empty commit_list, and is updated to point to the "next" field of
1352 * the last item on the list as new commits are appended.
1353 *
1354 * Usage example:
1355 *
1356 * struct commit_list *list;
1357 * struct commit_list **next = &list;
1358 *
1359 * next = commit_list_append(c1, next);
1360 * next = commit_list_append(c2, next);
1361 * assert(commit_list_count(list) == 2);
1362 * return list;
1363 */
1364struct commit_list **commit_list_append(struct commit *commit,
1365 struct commit_list **next)
1366{
1367 struct commit_list *new = xmalloc(sizeof(struct commit_list));
1368 new->item = commit;
1369 *next = new;
1370 new->next = NULL;
1371 return &new->next;
1372}
1373void print_commit_list(struct commit_list *list,
1375 const char *format_cur,
1376 const char *format_last)
1377{
1378 for ( ; list; list = list->next) {
1379 const char *format = list->next ? format_cur : format_last;
1380 printf(format, sha1_to_hex(list->item->object.sha1));
1381 }
1382}