provide helpers to access the commit buffer
[git.git] / commit.c
blobb6b0e0d6fbe3628c39e4bc14f8301b89b6b4e834
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"
15 static struct commit_extra_header *read_commit_extra_header_lines(const char *buf, size_t len, const char **);
17 int save_commit_buffer = 1;
19 const char *commit_type = "commit";
21 static struct commit *check_commit(struct object *obj,
22 const unsigned char *sha1,
23 int quiet)
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;
31 return (struct commit *) obj;
34 struct commit *lookup_commit_reference_gently(const unsigned char *sha1,
35 int quiet)
37 struct object *obj = deref_tag(parse_object(sha1), NULL, 0);
39 if (!obj)
40 return NULL;
41 return check_commit(obj, sha1, quiet);
44 struct commit *lookup_commit_reference(const unsigned char *sha1)
46 return lookup_commit_reference_gently(sha1, 0);
49 struct commit *lookup_commit_or_die(const unsigned char *sha1, const char *ref_name)
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));
58 return c;
61 struct commit *lookup_commit(const unsigned char *sha1)
63 struct object *obj = lookup_object(sha1);
64 if (!obj) {
65 struct commit *c = alloc_commit_node();
66 return create_object(sha1, OBJ_COMMIT, c);
68 if (!obj->type)
69 obj->type = OBJ_COMMIT;
70 return check_commit(obj, sha1, 0);
73 struct commit *lookup_commit_reference_by_name(const char *name)
75 unsigned char sha1[20];
76 struct commit *commit;
78 if (get_sha1_committish(name, sha1))
79 return NULL;
80 commit = lookup_commit_reference(sha1);
81 if (parse_commit(commit))
82 return NULL;
83 return commit;
86 static unsigned long parse_commit_date(const char *buf, const char *tail)
88 const char *dateptr;
90 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);
113 static struct commit_graft **commit_graft;
114 static int commit_graft_alloc, commit_graft_nr;
116 static const unsigned char *commit_graft_sha1_access(size_t index, void *table)
118 struct commit_graft **commit_graft_table = table;
119 return commit_graft_table[index]->sha1;
122 static int commit_graft_pos(const unsigned char *sha1)
124 return sha1_pos(sha1, commit_graft, commit_graft_nr,
125 commit_graft_sha1_access);
128 int register_commit_graft(struct commit_graft *graft, int ignore_dups)
130 int pos = commit_graft_pos(graft->sha1);
132 if (0 <= pos) {
133 if (ignore_dups)
134 free(graft);
135 else {
136 free(commit_graft[pos]);
137 commit_graft[pos] = graft;
139 return 1;
141 pos = -pos - 1;
142 ALLOC_GROW(commit_graft, commit_graft_nr + 1, commit_graft_alloc);
143 commit_graft_nr++;
144 if (pos < commit_graft_nr)
145 memmove(commit_graft + pos + 1,
146 commit_graft + pos,
147 (commit_graft_nr - pos - 1) *
148 sizeof(*commit_graft));
149 commit_graft[pos] = graft;
150 return 0;
153 struct commit_graft *read_graft_line(char *buf, int len)
155 /* The format is just "Commit Parent1 Parent2 ...\n" */
156 int i;
157 struct commit_graft *graft = NULL;
159 while (len && isspace(buf[len-1]))
160 buf[--len] = '\0';
161 if (buf[0] == '#' || buf[0] == '\0')
162 return NULL;
163 if ((len + 1) % 41)
164 goto bad_graft_data;
165 i = (len + 1) / 41 - 1;
166 graft = xmalloc(sizeof(*graft) + 20 * i);
167 graft->nr_parent = i;
168 if (get_sha1_hex(buf, graft->sha1))
169 goto bad_graft_data;
170 for (i = 40; i < len; i += 41) {
171 if (buf[i] != ' ')
172 goto bad_graft_data;
173 if (get_sha1_hex(buf + i + 1, graft->parent[i/41]))
174 goto bad_graft_data;
176 return graft;
178 bad_graft_data:
179 error("bad graft data: %s", buf);
180 free(graft);
181 return NULL;
184 static int read_graft_file(const char *graft_file)
186 FILE *fp = fopen(graft_file, "r");
187 struct strbuf buf = STRBUF_INIT;
188 if (!fp)
189 return -1;
190 while (!strbuf_getwholeline(&buf, fp, '\n')) {
191 /* The format is just "Commit Parent1 Parent2 ...\n" */
192 struct commit_graft *graft = read_graft_line(buf.buf, buf.len);
193 if (!graft)
194 continue;
195 if (register_commit_graft(graft, 1))
196 error("duplicate graft data: %s", buf.buf);
198 fclose(fp);
199 strbuf_release(&buf);
200 return 0;
203 static void prepare_commit_graft(void)
205 static int commit_graft_prepared;
206 char *graft_file;
208 if (commit_graft_prepared)
209 return;
210 graft_file = get_graft_file();
211 read_graft_file(graft_file);
212 /* make sure shallows are read */
213 is_repository_shallow();
214 commit_graft_prepared = 1;
217 struct commit_graft *lookup_commit_graft(const unsigned char *sha1)
219 int pos;
220 prepare_commit_graft();
221 pos = commit_graft_pos(sha1);
222 if (pos < 0)
223 return NULL;
224 return commit_graft[pos];
227 int for_each_commit_graft(each_commit_graft_fn fn, void *cb_data)
229 int i, ret;
230 for (i = ret = 0; i < commit_graft_nr && !ret; i++)
231 ret = fn(commit_graft[i], cb_data);
232 return ret;
235 int unregister_shallow(const unsigned char *sha1)
237 int pos = commit_graft_pos(sha1);
238 if (pos < 0)
239 return -1;
240 if (pos + 1 < commit_graft_nr)
241 memmove(commit_graft + pos, commit_graft + pos + 1,
242 sizeof(struct commit_graft *)
243 * (commit_graft_nr - pos - 1));
244 commit_graft_nr--;
245 return 0;
248 void set_commit_buffer(struct commit *commit, void *buffer)
250 commit->buffer = buffer;
253 const void *get_cached_commit_buffer(const struct commit *commit)
255 return commit->buffer;
258 const void *get_commit_buffer(const struct commit *commit)
260 const void *ret = get_cached_commit_buffer(commit);
261 if (!ret) {
262 enum object_type type;
263 unsigned long size;
264 ret = read_sha1_file(commit->object.sha1, &type, &size);
265 if (!ret)
266 die("cannot read commit object %s",
267 sha1_to_hex(commit->object.sha1));
268 if (type != OBJ_COMMIT)
269 die("expected commit for %s, got %s",
270 sha1_to_hex(commit->object.sha1), typename(type));
272 return ret;
275 void unuse_commit_buffer(const struct commit *commit, const void *buffer)
277 if (commit->buffer != buffer)
278 free((void *)buffer);
281 void free_commit_buffer(struct commit *commit)
283 free(commit->buffer);
284 commit->buffer = NULL;
287 const void *detach_commit_buffer(struct commit *commit)
289 void *ret = commit->buffer;
290 commit->buffer = NULL;
291 return ret;
294 int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long size)
296 const char *tail = buffer;
297 const char *bufptr = buffer;
298 unsigned char parent[20];
299 struct commit_list **pptr;
300 struct commit_graft *graft;
302 if (item->object.parsed)
303 return 0;
304 item->object.parsed = 1;
305 tail += size;
306 if (tail <= bufptr + 46 || memcmp(bufptr, "tree ", 5) || bufptr[45] != '\n')
307 return error("bogus commit object %s", sha1_to_hex(item->object.sha1));
308 if (get_sha1_hex(bufptr + 5, parent) < 0)
309 return error("bad tree pointer in commit %s",
310 sha1_to_hex(item->object.sha1));
311 item->tree = lookup_tree(parent);
312 bufptr += 46; /* "tree " + "hex sha1" + "\n" */
313 pptr = &item->parents;
315 graft = lookup_commit_graft(item->object.sha1);
316 while (bufptr + 48 < tail && !memcmp(bufptr, "parent ", 7)) {
317 struct commit *new_parent;
319 if (tail <= bufptr + 48 ||
320 get_sha1_hex(bufptr + 7, parent) ||
321 bufptr[47] != '\n')
322 return error("bad parents in commit %s", sha1_to_hex(item->object.sha1));
323 bufptr += 48;
325 * The clone is shallow if nr_parent < 0, and we must
326 * not traverse its real parents even when we unhide them.
328 if (graft && (graft->nr_parent < 0 || grafts_replace_parents))
329 continue;
330 new_parent = lookup_commit(parent);
331 if (new_parent)
332 pptr = &commit_list_insert(new_parent, pptr)->next;
334 if (graft) {
335 int i;
336 struct commit *new_parent;
337 for (i = 0; i < graft->nr_parent; i++) {
338 new_parent = lookup_commit(graft->parent[i]);
339 if (!new_parent)
340 continue;
341 pptr = &commit_list_insert(new_parent, pptr)->next;
344 item->date = parse_commit_date(bufptr, tail);
346 return 0;
349 int parse_commit(struct commit *item)
351 enum object_type type;
352 void *buffer;
353 unsigned long size;
354 int ret;
356 if (!item)
357 return -1;
358 if (item->object.parsed)
359 return 0;
360 buffer = read_sha1_file(item->object.sha1, &type, &size);
361 if (!buffer)
362 return error("Could not read %s",
363 sha1_to_hex(item->object.sha1));
364 if (type != OBJ_COMMIT) {
365 free(buffer);
366 return error("Object %s not a commit",
367 sha1_to_hex(item->object.sha1));
369 ret = parse_commit_buffer(item, buffer, size);
370 if (save_commit_buffer && !ret) {
371 set_commit_buffer(item, buffer);
372 return 0;
374 free(buffer);
375 return ret;
378 void parse_commit_or_die(struct commit *item)
380 if (parse_commit(item))
381 die("unable to parse commit %s",
382 item ? sha1_to_hex(item->object.sha1) : "(null)");
385 int find_commit_subject(const char *commit_buffer, const char **subject)
387 const char *eol;
388 const char *p = commit_buffer;
390 while (*p && (*p != '\n' || p[1] != '\n'))
391 p++;
392 if (*p) {
393 p += 2;
394 for (eol = p; *eol && *eol != '\n'; eol++)
395 ; /* do nothing */
396 } else
397 eol = p;
399 *subject = p;
401 return eol - p;
404 struct commit_list *commit_list_insert(struct commit *item, struct commit_list **list_p)
406 struct commit_list *new_list = xmalloc(sizeof(struct commit_list));
407 new_list->item = item;
408 new_list->next = *list_p;
409 *list_p = new_list;
410 return new_list;
413 unsigned commit_list_count(const struct commit_list *l)
415 unsigned c = 0;
416 for (; l; l = l->next )
417 c++;
418 return c;
421 struct commit_list *copy_commit_list(struct commit_list *list)
423 struct commit_list *head = NULL;
424 struct commit_list **pp = &head;
425 while (list) {
426 struct commit_list *new;
427 new = xmalloc(sizeof(struct commit_list));
428 new->item = list->item;
429 new->next = NULL;
430 *pp = new;
431 pp = &new->next;
432 list = list->next;
434 return head;
437 void free_commit_list(struct commit_list *list)
439 while (list) {
440 struct commit_list *temp = list;
441 list = temp->next;
442 free(temp);
446 struct commit_list * commit_list_insert_by_date(struct commit *item, struct commit_list **list)
448 struct commit_list **pp = list;
449 struct commit_list *p;
450 while ((p = *pp) != NULL) {
451 if (p->item->date < item->date) {
452 break;
454 pp = &p->next;
456 return commit_list_insert(item, pp);
459 static int commit_list_compare_by_date(const void *a, const void *b)
461 unsigned long a_date = ((const struct commit_list *)a)->item->date;
462 unsigned long b_date = ((const struct commit_list *)b)->item->date;
463 if (a_date < b_date)
464 return 1;
465 if (a_date > b_date)
466 return -1;
467 return 0;
470 static void *commit_list_get_next(const void *a)
472 return ((const struct commit_list *)a)->next;
475 static void commit_list_set_next(void *a, void *next)
477 ((struct commit_list *)a)->next = next;
480 void commit_list_sort_by_date(struct commit_list **list)
482 *list = llist_mergesort(*list, commit_list_get_next, commit_list_set_next,
483 commit_list_compare_by_date);
486 struct commit *pop_most_recent_commit(struct commit_list **list,
487 unsigned int mark)
489 struct commit *ret = (*list)->item;
490 struct commit_list *parents = ret->parents;
491 struct commit_list *old = *list;
493 *list = (*list)->next;
494 free(old);
496 while (parents) {
497 struct commit *commit = parents->item;
498 if (!parse_commit(commit) && !(commit->object.flags & mark)) {
499 commit->object.flags |= mark;
500 commit_list_insert_by_date(commit, list);
502 parents = parents->next;
504 return ret;
507 static void clear_commit_marks_1(struct commit_list **plist,
508 struct commit *commit, unsigned int mark)
510 while (commit) {
511 struct commit_list *parents;
513 if (!(mark & commit->object.flags))
514 return;
516 commit->object.flags &= ~mark;
518 parents = commit->parents;
519 if (!parents)
520 return;
522 while ((parents = parents->next))
523 commit_list_insert(parents->item, plist);
525 commit = commit->parents->item;
529 void clear_commit_marks_many(int nr, struct commit **commit, unsigned int mark)
531 struct commit_list *list = NULL;
533 while (nr--) {
534 commit_list_insert(*commit, &list);
535 commit++;
537 while (list)
538 clear_commit_marks_1(&list, pop_commit(&list), mark);
541 void clear_commit_marks(struct commit *commit, unsigned int mark)
543 clear_commit_marks_many(1, &commit, mark);
546 void clear_commit_marks_for_object_array(struct object_array *a, unsigned mark)
548 struct object *object;
549 struct commit *commit;
550 unsigned int i;
552 for (i = 0; i < a->nr; i++) {
553 object = a->objects[i].item;
554 commit = lookup_commit_reference_gently(object->sha1, 1);
555 if (commit)
556 clear_commit_marks(commit, mark);
560 struct commit *pop_commit(struct commit_list **stack)
562 struct commit_list *top = *stack;
563 struct commit *item = top ? top->item : NULL;
565 if (top) {
566 *stack = top->next;
567 free(top);
569 return item;
573 * Topological sort support
576 /* count number of children that have not been emitted */
577 define_commit_slab(indegree_slab, int);
579 /* record author-date for each commit object */
580 define_commit_slab(author_date_slab, unsigned long);
582 static void record_author_date(struct author_date_slab *author_date,
583 struct commit *commit)
585 const char *buf, *line_end, *ident_line;
586 char *buffer = NULL;
587 struct ident_split ident;
588 char *date_end;
589 unsigned long date;
591 if (!commit->buffer) {
592 unsigned long size;
593 enum object_type type;
594 buffer = read_sha1_file(commit->object.sha1, &type, &size);
595 if (!buffer)
596 return;
599 for (buf = commit->buffer ? commit->buffer : buffer;
600 buf;
601 buf = line_end + 1) {
602 line_end = strchrnul(buf, '\n');
603 ident_line = skip_prefix(buf, "author ");
604 if (!ident_line) {
605 if (!line_end[0] || line_end[1] == '\n')
606 return; /* end of header */
607 continue;
609 if (split_ident_line(&ident,
610 ident_line, line_end - ident_line) ||
611 !ident.date_begin || !ident.date_end)
612 goto fail_exit; /* malformed "author" line */
613 break;
616 date = strtoul(ident.date_begin, &date_end, 10);
617 if (date_end != ident.date_end)
618 goto fail_exit; /* malformed date */
619 *(author_date_slab_at(author_date, commit)) = date;
621 fail_exit:
622 free(buffer);
625 static int compare_commits_by_author_date(const void *a_, const void *b_,
626 void *cb_data)
628 const struct commit *a = a_, *b = b_;
629 struct author_date_slab *author_date = cb_data;
630 unsigned long a_date = *(author_date_slab_at(author_date, a));
631 unsigned long b_date = *(author_date_slab_at(author_date, b));
633 /* newer commits with larger date first */
634 if (a_date < b_date)
635 return 1;
636 else if (a_date > b_date)
637 return -1;
638 return 0;
641 int compare_commits_by_commit_date(const void *a_, const void *b_, void *unused)
643 const struct commit *a = a_, *b = b_;
644 /* newer commits with larger date first */
645 if (a->date < b->date)
646 return 1;
647 else if (a->date > b->date)
648 return -1;
649 return 0;
653 * Performs an in-place topological sort on the list supplied.
655 void sort_in_topological_order(struct commit_list **list, enum rev_sort_order sort_order)
657 struct commit_list *next, *orig = *list;
658 struct commit_list **pptr;
659 struct indegree_slab indegree;
660 struct prio_queue queue;
661 struct commit *commit;
662 struct author_date_slab author_date;
664 if (!orig)
665 return;
666 *list = NULL;
668 init_indegree_slab(&indegree);
669 memset(&queue, '\0', sizeof(queue));
671 switch (sort_order) {
672 default: /* REV_SORT_IN_GRAPH_ORDER */
673 queue.compare = NULL;
674 break;
675 case REV_SORT_BY_COMMIT_DATE:
676 queue.compare = compare_commits_by_commit_date;
677 break;
678 case REV_SORT_BY_AUTHOR_DATE:
679 init_author_date_slab(&author_date);
680 queue.compare = compare_commits_by_author_date;
681 queue.cb_data = &author_date;
682 break;
685 /* Mark them and clear the indegree */
686 for (next = orig; next; next = next->next) {
687 struct commit *commit = next->item;
688 *(indegree_slab_at(&indegree, commit)) = 1;
689 /* also record the author dates, if needed */
690 if (sort_order == REV_SORT_BY_AUTHOR_DATE)
691 record_author_date(&author_date, commit);
694 /* update the indegree */
695 for (next = orig; next; next = next->next) {
696 struct commit_list *parents = next->item->parents;
697 while (parents) {
698 struct commit *parent = parents->item;
699 int *pi = indegree_slab_at(&indegree, parent);
701 if (*pi)
702 (*pi)++;
703 parents = parents->next;
708 * find the tips
710 * tips are nodes not reachable from any other node in the list
712 * the tips serve as a starting set for the work queue.
714 for (next = orig; next; next = next->next) {
715 struct commit *commit = next->item;
717 if (*(indegree_slab_at(&indegree, commit)) == 1)
718 prio_queue_put(&queue, commit);
722 * This is unfortunate; the initial tips need to be shown
723 * in the order given from the revision traversal machinery.
725 if (sort_order == REV_SORT_IN_GRAPH_ORDER)
726 prio_queue_reverse(&queue);
728 /* We no longer need the commit list */
729 free_commit_list(orig);
731 pptr = list;
732 *list = NULL;
733 while ((commit = prio_queue_get(&queue)) != NULL) {
734 struct commit_list *parents;
736 for (parents = commit->parents; parents ; parents = parents->next) {
737 struct commit *parent = parents->item;
738 int *pi = indegree_slab_at(&indegree, parent);
740 if (!*pi)
741 continue;
744 * parents are only enqueued for emission
745 * when all their children have been emitted thereby
746 * guaranteeing topological order.
748 if (--(*pi) == 1)
749 prio_queue_put(&queue, parent);
752 * all children of commit have already been
753 * emitted. we can emit it now.
755 *(indegree_slab_at(&indegree, commit)) = 0;
757 pptr = &commit_list_insert(commit, pptr)->next;
760 clear_indegree_slab(&indegree);
761 clear_prio_queue(&queue);
762 if (sort_order == REV_SORT_BY_AUTHOR_DATE)
763 clear_author_date_slab(&author_date);
766 /* merge-base stuff */
768 /* Remember to update object flag allocation in object.h */
769 #define PARENT1 (1u<<16)
770 #define PARENT2 (1u<<17)
771 #define STALE (1u<<18)
772 #define RESULT (1u<<19)
774 static const unsigned all_flags = (PARENT1 | PARENT2 | STALE | RESULT);
776 static struct commit *interesting(struct commit_list *list)
778 while (list) {
779 struct commit *commit = list->item;
780 list = list->next;
781 if (commit->object.flags & STALE)
782 continue;
783 return commit;
785 return NULL;
788 /* all input commits in one and twos[] must have been parsed! */
789 static struct commit_list *paint_down_to_common(struct commit *one, int n, struct commit **twos)
791 struct commit_list *list = NULL;
792 struct commit_list *result = NULL;
793 int i;
795 one->object.flags |= PARENT1;
796 commit_list_insert_by_date(one, &list);
797 if (!n)
798 return list;
799 for (i = 0; i < n; i++) {
800 twos[i]->object.flags |= PARENT2;
801 commit_list_insert_by_date(twos[i], &list);
804 while (interesting(list)) {
805 struct commit *commit;
806 struct commit_list *parents;
807 struct commit_list *next;
808 int flags;
810 commit = list->item;
811 next = list->next;
812 free(list);
813 list = next;
815 flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
816 if (flags == (PARENT1 | PARENT2)) {
817 if (!(commit->object.flags & RESULT)) {
818 commit->object.flags |= RESULT;
819 commit_list_insert_by_date(commit, &result);
821 /* Mark parents of a found merge stale */
822 flags |= STALE;
824 parents = commit->parents;
825 while (parents) {
826 struct commit *p = parents->item;
827 parents = parents->next;
828 if ((p->object.flags & flags) == flags)
829 continue;
830 if (parse_commit(p))
831 return NULL;
832 p->object.flags |= flags;
833 commit_list_insert_by_date(p, &list);
837 free_commit_list(list);
838 return result;
841 static struct commit_list *merge_bases_many(struct commit *one, int n, struct commit **twos)
843 struct commit_list *list = NULL;
844 struct commit_list *result = NULL;
845 int i;
847 for (i = 0; i < n; i++) {
848 if (one == twos[i])
850 * We do not mark this even with RESULT so we do not
851 * have to clean it up.
853 return commit_list_insert(one, &result);
856 if (parse_commit(one))
857 return NULL;
858 for (i = 0; i < n; i++) {
859 if (parse_commit(twos[i]))
860 return NULL;
863 list = paint_down_to_common(one, n, twos);
865 while (list) {
866 struct commit_list *next = list->next;
867 if (!(list->item->object.flags & STALE))
868 commit_list_insert_by_date(list->item, &result);
869 free(list);
870 list = next;
872 return result;
875 struct commit_list *get_octopus_merge_bases(struct commit_list *in)
877 struct commit_list *i, *j, *k, *ret = NULL;
879 if (!in)
880 return ret;
882 commit_list_insert(in->item, &ret);
884 for (i = in->next; i; i = i->next) {
885 struct commit_list *new = NULL, *end = NULL;
887 for (j = ret; j; j = j->next) {
888 struct commit_list *bases;
889 bases = get_merge_bases(i->item, j->item, 1);
890 if (!new)
891 new = bases;
892 else
893 end->next = bases;
894 for (k = bases; k; k = k->next)
895 end = k;
897 ret = new;
899 return ret;
902 static int remove_redundant(struct commit **array, int cnt)
905 * Some commit in the array may be an ancestor of
906 * another commit. Move such commit to the end of
907 * the array, and return the number of commits that
908 * are independent from each other.
910 struct commit **work;
911 unsigned char *redundant;
912 int *filled_index;
913 int i, j, filled;
915 work = xcalloc(cnt, sizeof(*work));
916 redundant = xcalloc(cnt, 1);
917 filled_index = xmalloc(sizeof(*filled_index) * (cnt - 1));
919 for (i = 0; i < cnt; i++)
920 parse_commit(array[i]);
921 for (i = 0; i < cnt; i++) {
922 struct commit_list *common;
924 if (redundant[i])
925 continue;
926 for (j = filled = 0; j < cnt; j++) {
927 if (i == j || redundant[j])
928 continue;
929 filled_index[filled] = j;
930 work[filled++] = array[j];
932 common = paint_down_to_common(array[i], filled, work);
933 if (array[i]->object.flags & PARENT2)
934 redundant[i] = 1;
935 for (j = 0; j < filled; j++)
936 if (work[j]->object.flags & PARENT1)
937 redundant[filled_index[j]] = 1;
938 clear_commit_marks(array[i], all_flags);
939 for (j = 0; j < filled; j++)
940 clear_commit_marks(work[j], all_flags);
941 free_commit_list(common);
944 /* Now collect the result */
945 memcpy(work, array, sizeof(*array) * cnt);
946 for (i = filled = 0; i < cnt; i++)
947 if (!redundant[i])
948 array[filled++] = work[i];
949 for (j = filled, i = 0; i < cnt; i++)
950 if (redundant[i])
951 array[j++] = work[i];
952 free(work);
953 free(redundant);
954 free(filled_index);
955 return filled;
958 struct commit_list *get_merge_bases_many(struct commit *one,
959 int n,
960 struct commit **twos,
961 int cleanup)
963 struct commit_list *list;
964 struct commit **rslt;
965 struct commit_list *result;
966 int cnt, i;
968 result = merge_bases_many(one, n, twos);
969 for (i = 0; i < n; i++) {
970 if (one == twos[i])
971 return result;
973 if (!result || !result->next) {
974 if (cleanup) {
975 clear_commit_marks(one, all_flags);
976 clear_commit_marks_many(n, twos, all_flags);
978 return result;
981 /* There are more than one */
982 cnt = 0;
983 list = result;
984 while (list) {
985 list = list->next;
986 cnt++;
988 rslt = xcalloc(cnt, sizeof(*rslt));
989 for (list = result, i = 0; list; list = list->next)
990 rslt[i++] = list->item;
991 free_commit_list(result);
993 clear_commit_marks(one, all_flags);
994 clear_commit_marks_many(n, twos, all_flags);
996 cnt = remove_redundant(rslt, cnt);
997 result = NULL;
998 for (i = 0; i < cnt; i++)
999 commit_list_insert_by_date(rslt[i], &result);
1000 free(rslt);
1001 return result;
1004 struct commit_list *get_merge_bases(struct commit *one, struct commit *two,
1005 int cleanup)
1007 return get_merge_bases_many(one, 1, &two, cleanup);
1011 * Is "commit" a descendant of one of the elements on the "with_commit" list?
1013 int is_descendant_of(struct commit *commit, struct commit_list *with_commit)
1015 if (!with_commit)
1016 return 1;
1017 while (with_commit) {
1018 struct commit *other;
1020 other = with_commit->item;
1021 with_commit = with_commit->next;
1022 if (in_merge_bases(other, commit))
1023 return 1;
1025 return 0;
1029 * Is "commit" an ancestor of one of the "references"?
1031 int in_merge_bases_many(struct commit *commit, int nr_reference, struct commit **reference)
1033 struct commit_list *bases;
1034 int ret = 0, i;
1036 if (parse_commit(commit))
1037 return ret;
1038 for (i = 0; i < nr_reference; i++)
1039 if (parse_commit(reference[i]))
1040 return ret;
1042 bases = paint_down_to_common(commit, nr_reference, reference);
1043 if (commit->object.flags & PARENT2)
1044 ret = 1;
1045 clear_commit_marks(commit, all_flags);
1046 clear_commit_marks_many(nr_reference, reference, all_flags);
1047 free_commit_list(bases);
1048 return ret;
1052 * Is "commit" an ancestor of (i.e. reachable from) the "reference"?
1054 int in_merge_bases(struct commit *commit, struct commit *reference)
1056 return in_merge_bases_many(commit, 1, &reference);
1059 struct commit_list *reduce_heads(struct commit_list *heads)
1061 struct commit_list *p;
1062 struct commit_list *result = NULL, **tail = &result;
1063 struct commit **array;
1064 int num_head, i;
1066 if (!heads)
1067 return NULL;
1069 /* Uniquify */
1070 for (p = heads; p; p = p->next)
1071 p->item->object.flags &= ~STALE;
1072 for (p = heads, num_head = 0; p; p = p->next) {
1073 if (p->item->object.flags & STALE)
1074 continue;
1075 p->item->object.flags |= STALE;
1076 num_head++;
1078 array = xcalloc(sizeof(*array), num_head);
1079 for (p = heads, i = 0; p; p = p->next) {
1080 if (p->item->object.flags & STALE) {
1081 array[i++] = p->item;
1082 p->item->object.flags &= ~STALE;
1085 num_head = remove_redundant(array, num_head);
1086 for (i = 0; i < num_head; i++)
1087 tail = &commit_list_insert(array[i], tail)->next;
1088 return result;
1091 static const char gpg_sig_header[] = "gpgsig";
1092 static const int gpg_sig_header_len = sizeof(gpg_sig_header) - 1;
1094 static int do_sign_commit(struct strbuf *buf, const char *keyid)
1096 struct strbuf sig = STRBUF_INIT;
1097 int inspos, copypos;
1099 /* find the end of the header */
1100 inspos = strstr(buf->buf, "\n\n") - buf->buf + 1;
1102 if (!keyid || !*keyid)
1103 keyid = get_signing_key();
1104 if (sign_buffer(buf, &sig, keyid)) {
1105 strbuf_release(&sig);
1106 return -1;
1109 for (copypos = 0; sig.buf[copypos]; ) {
1110 const char *bol = sig.buf + copypos;
1111 const char *eol = strchrnul(bol, '\n');
1112 int len = (eol - bol) + !!*eol;
1114 if (!copypos) {
1115 strbuf_insert(buf, inspos, gpg_sig_header, gpg_sig_header_len);
1116 inspos += gpg_sig_header_len;
1118 strbuf_insert(buf, inspos++, " ", 1);
1119 strbuf_insert(buf, inspos, bol, len);
1120 inspos += len;
1121 copypos += len;
1123 strbuf_release(&sig);
1124 return 0;
1127 int parse_signed_commit(const unsigned char *sha1,
1128 struct strbuf *payload, struct strbuf *signature)
1130 unsigned long size;
1131 enum object_type type;
1132 char *buffer = read_sha1_file(sha1, &type, &size);
1133 int in_signature, saw_signature = -1;
1134 char *line, *tail;
1136 if (!buffer || type != OBJ_COMMIT)
1137 goto cleanup;
1139 line = buffer;
1140 tail = buffer + size;
1141 in_signature = 0;
1142 saw_signature = 0;
1143 while (line < tail) {
1144 const char *sig = NULL;
1145 char *next = memchr(line, '\n', tail - line);
1147 next = next ? next + 1 : tail;
1148 if (in_signature && line[0] == ' ')
1149 sig = line + 1;
1150 else if (starts_with(line, gpg_sig_header) &&
1151 line[gpg_sig_header_len] == ' ')
1152 sig = line + gpg_sig_header_len + 1;
1153 if (sig) {
1154 strbuf_add(signature, sig, next - sig);
1155 saw_signature = 1;
1156 in_signature = 1;
1157 } else {
1158 if (*line == '\n')
1159 /* dump the whole remainder of the buffer */
1160 next = tail;
1161 strbuf_add(payload, line, next - line);
1162 in_signature = 0;
1164 line = next;
1166 cleanup:
1167 free(buffer);
1168 return saw_signature;
1171 static void handle_signed_tag(struct commit *parent, struct commit_extra_header ***tail)
1173 struct merge_remote_desc *desc;
1174 struct commit_extra_header *mergetag;
1175 char *buf;
1176 unsigned long size, len;
1177 enum object_type type;
1179 desc = merge_remote_util(parent);
1180 if (!desc || !desc->obj)
1181 return;
1182 buf = read_sha1_file(desc->obj->sha1, &type, &size);
1183 if (!buf || type != OBJ_TAG)
1184 goto free_return;
1185 len = parse_signature(buf, size);
1186 if (size == len)
1187 goto free_return;
1189 * We could verify this signature and either omit the tag when
1190 * it does not validate, but the integrator may not have the
1191 * public key of the signer of the tag he is merging, while a
1192 * later auditor may have it while auditing, so let's not run
1193 * verify-signed-buffer here for now...
1195 * if (verify_signed_buffer(buf, len, buf + len, size - len, ...))
1196 * warn("warning: signed tag unverified.");
1198 mergetag = xcalloc(1, sizeof(*mergetag));
1199 mergetag->key = xstrdup("mergetag");
1200 mergetag->value = buf;
1201 mergetag->len = size;
1203 **tail = mergetag;
1204 *tail = &mergetag->next;
1205 return;
1207 free_return:
1208 free(buf);
1211 static struct {
1212 char result;
1213 const char *check;
1214 } sigcheck_gpg_status[] = {
1215 { 'G', "\n[GNUPG:] GOODSIG " },
1216 { 'B', "\n[GNUPG:] BADSIG " },
1217 { 'U', "\n[GNUPG:] TRUST_NEVER" },
1218 { 'U', "\n[GNUPG:] TRUST_UNDEFINED" },
1221 static void parse_gpg_output(struct signature_check *sigc)
1223 const char *buf = sigc->gpg_status;
1224 int i;
1226 /* Iterate over all search strings */
1227 for (i = 0; i < ARRAY_SIZE(sigcheck_gpg_status); i++) {
1228 const char *found, *next;
1230 found = skip_prefix(buf, sigcheck_gpg_status[i].check + 1);
1231 if (!found) {
1232 found = strstr(buf, sigcheck_gpg_status[i].check);
1233 if (!found)
1234 continue;
1235 found += strlen(sigcheck_gpg_status[i].check);
1237 sigc->result = sigcheck_gpg_status[i].result;
1238 /* The trust messages are not followed by key/signer information */
1239 if (sigc->result != 'U') {
1240 sigc->key = xmemdupz(found, 16);
1241 found += 17;
1242 next = strchrnul(found, '\n');
1243 sigc->signer = xmemdupz(found, next - found);
1248 void check_commit_signature(const struct commit* commit, struct signature_check *sigc)
1250 struct strbuf payload = STRBUF_INIT;
1251 struct strbuf signature = STRBUF_INIT;
1252 struct strbuf gpg_output = STRBUF_INIT;
1253 struct strbuf gpg_status = STRBUF_INIT;
1254 int status;
1256 sigc->result = 'N';
1258 if (parse_signed_commit(commit->object.sha1,
1259 &payload, &signature) <= 0)
1260 goto out;
1261 status = verify_signed_buffer(payload.buf, payload.len,
1262 signature.buf, signature.len,
1263 &gpg_output, &gpg_status);
1264 if (status && !gpg_output.len)
1265 goto out;
1266 sigc->gpg_output = strbuf_detach(&gpg_output, NULL);
1267 sigc->gpg_status = strbuf_detach(&gpg_status, NULL);
1268 parse_gpg_output(sigc);
1270 out:
1271 strbuf_release(&gpg_status);
1272 strbuf_release(&gpg_output);
1273 strbuf_release(&payload);
1274 strbuf_release(&signature);
1279 void append_merge_tag_headers(struct commit_list *parents,
1280 struct commit_extra_header ***tail)
1282 while (parents) {
1283 struct commit *parent = parents->item;
1284 handle_signed_tag(parent, tail);
1285 parents = parents->next;
1289 static void add_extra_header(struct strbuf *buffer,
1290 struct commit_extra_header *extra)
1292 strbuf_addstr(buffer, extra->key);
1293 if (extra->len)
1294 strbuf_add_lines(buffer, " ", extra->value, extra->len);
1295 else
1296 strbuf_addch(buffer, '\n');
1299 struct commit_extra_header *read_commit_extra_headers(struct commit *commit,
1300 const char **exclude)
1302 struct commit_extra_header *extra = NULL;
1303 unsigned long size;
1304 enum object_type type;
1305 char *buffer = read_sha1_file(commit->object.sha1, &type, &size);
1306 if (buffer && type == OBJ_COMMIT)
1307 extra = read_commit_extra_header_lines(buffer, size, exclude);
1308 free(buffer);
1309 return extra;
1312 static inline int standard_header_field(const char *field, size_t len)
1314 return ((len == 4 && !memcmp(field, "tree ", 5)) ||
1315 (len == 6 && !memcmp(field, "parent ", 7)) ||
1316 (len == 6 && !memcmp(field, "author ", 7)) ||
1317 (len == 9 && !memcmp(field, "committer ", 10)) ||
1318 (len == 8 && !memcmp(field, "encoding ", 9)));
1321 static int excluded_header_field(const char *field, size_t len, const char **exclude)
1323 if (!exclude)
1324 return 0;
1326 while (*exclude) {
1327 size_t xlen = strlen(*exclude);
1328 if (len == xlen &&
1329 !memcmp(field, *exclude, xlen) && field[xlen] == ' ')
1330 return 1;
1331 exclude++;
1333 return 0;
1336 static struct commit_extra_header *read_commit_extra_header_lines(
1337 const char *buffer, size_t size,
1338 const char **exclude)
1340 struct commit_extra_header *extra = NULL, **tail = &extra, *it = NULL;
1341 const char *line, *next, *eof, *eob;
1342 struct strbuf buf = STRBUF_INIT;
1344 for (line = buffer, eob = line + size;
1345 line < eob && *line != '\n';
1346 line = next) {
1347 next = memchr(line, '\n', eob - line);
1348 next = next ? next + 1 : eob;
1349 if (*line == ' ') {
1350 /* continuation */
1351 if (it)
1352 strbuf_add(&buf, line + 1, next - (line + 1));
1353 continue;
1355 if (it)
1356 it->value = strbuf_detach(&buf, &it->len);
1357 strbuf_reset(&buf);
1358 it = NULL;
1360 eof = strchr(line, ' ');
1361 if (next <= eof)
1362 eof = next;
1364 if (standard_header_field(line, eof - line) ||
1365 excluded_header_field(line, eof - line, exclude))
1366 continue;
1368 it = xcalloc(1, sizeof(*it));
1369 it->key = xmemdupz(line, eof-line);
1370 *tail = it;
1371 tail = &it->next;
1372 if (eof + 1 < next)
1373 strbuf_add(&buf, eof + 1, next - (eof + 1));
1375 if (it)
1376 it->value = strbuf_detach(&buf, &it->len);
1377 return extra;
1380 void free_commit_extra_headers(struct commit_extra_header *extra)
1382 while (extra) {
1383 struct commit_extra_header *next = extra->next;
1384 free(extra->key);
1385 free(extra->value);
1386 free(extra);
1387 extra = next;
1391 int commit_tree(const char *msg, size_t msg_len,
1392 const unsigned char *tree,
1393 struct commit_list *parents, unsigned char *ret,
1394 const char *author, const char *sign_commit)
1396 struct commit_extra_header *extra = NULL, **tail = &extra;
1397 int result;
1399 append_merge_tag_headers(parents, &tail);
1400 result = commit_tree_extended(msg, msg_len, tree, parents, ret,
1401 author, sign_commit, extra);
1402 free_commit_extra_headers(extra);
1403 return result;
1406 static int find_invalid_utf8(const char *buf, int len)
1408 int offset = 0;
1409 static const unsigned int max_codepoint[] = {
1410 0x7f, 0x7ff, 0xffff, 0x10ffff
1413 while (len) {
1414 unsigned char c = *buf++;
1415 int bytes, bad_offset;
1416 unsigned int codepoint;
1417 unsigned int min_val, max_val;
1419 len--;
1420 offset++;
1422 /* Simple US-ASCII? No worries. */
1423 if (c < 0x80)
1424 continue;
1426 bad_offset = offset-1;
1429 * Count how many more high bits set: that's how
1430 * many more bytes this sequence should have.
1432 bytes = 0;
1433 while (c & 0x40) {
1434 c <<= 1;
1435 bytes++;
1439 * Must be between 1 and 3 more bytes. Longer sequences result in
1440 * codepoints beyond U+10FFFF, which are guaranteed never to exist.
1442 if (bytes < 1 || 3 < bytes)
1443 return bad_offset;
1445 /* Do we *have* that many bytes? */
1446 if (len < bytes)
1447 return bad_offset;
1450 * Place the encoded bits at the bottom of the value and compute the
1451 * valid range.
1453 codepoint = (c & 0x7f) >> bytes;
1454 min_val = max_codepoint[bytes-1] + 1;
1455 max_val = max_codepoint[bytes];
1457 offset += bytes;
1458 len -= bytes;
1460 /* And verify that they are good continuation bytes */
1461 do {
1462 codepoint <<= 6;
1463 codepoint |= *buf & 0x3f;
1464 if ((*buf++ & 0xc0) != 0x80)
1465 return bad_offset;
1466 } while (--bytes);
1468 /* Reject codepoints that are out of range for the sequence length. */
1469 if (codepoint < min_val || codepoint > max_val)
1470 return bad_offset;
1471 /* Surrogates are only for UTF-16 and cannot be encoded in UTF-8. */
1472 if ((codepoint & 0x1ff800) == 0xd800)
1473 return bad_offset;
1474 /* U+xxFFFE and U+xxFFFF are guaranteed non-characters. */
1475 if ((codepoint & 0xfffe) == 0xfffe)
1476 return bad_offset;
1477 /* So are anything in the range U+FDD0..U+FDEF. */
1478 if (codepoint >= 0xfdd0 && codepoint <= 0xfdef)
1479 return bad_offset;
1481 return -1;
1485 * This verifies that the buffer is in proper utf8 format.
1487 * If it isn't, it assumes any non-utf8 characters are Latin1,
1488 * and does the conversion.
1490 static int verify_utf8(struct strbuf *buf)
1492 int ok = 1;
1493 long pos = 0;
1495 for (;;) {
1496 int bad;
1497 unsigned char c;
1498 unsigned char replace[2];
1500 bad = find_invalid_utf8(buf->buf + pos, buf->len - pos);
1501 if (bad < 0)
1502 return ok;
1503 pos += bad;
1504 ok = 0;
1505 c = buf->buf[pos];
1506 strbuf_remove(buf, pos, 1);
1508 /* We know 'c' must be in the range 128-255 */
1509 replace[0] = 0xc0 + (c >> 6);
1510 replace[1] = 0x80 + (c & 0x3f);
1511 strbuf_insert(buf, pos, replace, 2);
1512 pos += 2;
1516 static const char commit_utf8_warn[] =
1517 "Warning: commit message did not conform to UTF-8.\n"
1518 "You may want to amend it after fixing the message, or set the config\n"
1519 "variable i18n.commitencoding to the encoding your project uses.\n";
1521 int commit_tree_extended(const char *msg, size_t msg_len,
1522 const unsigned char *tree,
1523 struct commit_list *parents, unsigned char *ret,
1524 const char *author, const char *sign_commit,
1525 struct commit_extra_header *extra)
1527 int result;
1528 int encoding_is_utf8;
1529 struct strbuf buffer;
1531 assert_sha1_type(tree, OBJ_TREE);
1533 if (memchr(msg, '\0', msg_len))
1534 return error("a NUL byte in commit log message not allowed.");
1536 /* Not having i18n.commitencoding is the same as having utf-8 */
1537 encoding_is_utf8 = is_encoding_utf8(git_commit_encoding);
1539 strbuf_init(&buffer, 8192); /* should avoid reallocs for the headers */
1540 strbuf_addf(&buffer, "tree %s\n", sha1_to_hex(tree));
1543 * NOTE! This ordering means that the same exact tree merged with a
1544 * different order of parents will be a _different_ changeset even
1545 * if everything else stays the same.
1547 while (parents) {
1548 struct commit_list *next = parents->next;
1549 struct commit *parent = parents->item;
1551 strbuf_addf(&buffer, "parent %s\n",
1552 sha1_to_hex(parent->object.sha1));
1553 free(parents);
1554 parents = next;
1557 /* Person/date information */
1558 if (!author)
1559 author = git_author_info(IDENT_STRICT);
1560 strbuf_addf(&buffer, "author %s\n", author);
1561 strbuf_addf(&buffer, "committer %s\n", git_committer_info(IDENT_STRICT));
1562 if (!encoding_is_utf8)
1563 strbuf_addf(&buffer, "encoding %s\n", git_commit_encoding);
1565 while (extra) {
1566 add_extra_header(&buffer, extra);
1567 extra = extra->next;
1569 strbuf_addch(&buffer, '\n');
1571 /* And add the comment */
1572 strbuf_add(&buffer, msg, msg_len);
1574 /* And check the encoding */
1575 if (encoding_is_utf8 && !verify_utf8(&buffer))
1576 fprintf(stderr, commit_utf8_warn);
1578 if (sign_commit && do_sign_commit(&buffer, sign_commit))
1579 return -1;
1581 result = write_sha1_file(buffer.buf, buffer.len, commit_type, ret);
1582 strbuf_release(&buffer);
1583 return result;
1586 struct commit *get_merge_parent(const char *name)
1588 struct object *obj;
1589 struct commit *commit;
1590 unsigned char sha1[20];
1591 if (get_sha1(name, sha1))
1592 return NULL;
1593 obj = parse_object(sha1);
1594 commit = (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
1595 if (commit && !commit->util) {
1596 struct merge_remote_desc *desc;
1597 desc = xmalloc(sizeof(*desc));
1598 desc->obj = obj;
1599 desc->name = strdup(name);
1600 commit->util = desc;
1602 return commit;
1606 * Append a commit to the end of the commit_list.
1608 * next starts by pointing to the variable that holds the head of an
1609 * empty commit_list, and is updated to point to the "next" field of
1610 * the last item on the list as new commits are appended.
1612 * Usage example:
1614 * struct commit_list *list;
1615 * struct commit_list **next = &list;
1617 * next = commit_list_append(c1, next);
1618 * next = commit_list_append(c2, next);
1619 * assert(commit_list_count(list) == 2);
1620 * return list;
1622 struct commit_list **commit_list_append(struct commit *commit,
1623 struct commit_list **next)
1625 struct commit_list *new = xmalloc(sizeof(struct commit_list));
1626 new->item = commit;
1627 *next = new;
1628 new->next = NULL;
1629 return &new->next;
1632 void print_commit_list(struct commit_list *list,
1633 const char *format_cur,
1634 const char *format_last)
1636 for ( ; list; list = list->next) {
1637 const char *format = list->next ? format_cur : format_last;
1638 printf(format, sha1_to_hex(list->item->object.sha1));