Merge branch 'esr/maint-doc-fast-import'
[git.git] / commit.c
blobe8eb0aec5509a4fd09698bd15a37d1f4e8341f5e
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"
12 static struct commit_extra_header *read_commit_extra_header_lines(const char *buf, size_t len, const char **);
14 int save_commit_buffer = 1;
16 const char *commit_type = "commit";
18 static struct commit *check_commit(struct object *obj,
19 const unsigned char *sha1,
20 int quiet)
22 if (obj->type != OBJ_COMMIT) {
23 if (!quiet)
24 error("Object %s is a %s, not a commit",
25 sha1_to_hex(sha1), typename(obj->type));
26 return NULL;
28 return (struct commit *) obj;
31 struct commit *lookup_commit_reference_gently(const unsigned char *sha1,
32 int quiet)
34 struct object *obj = deref_tag(parse_object(sha1), NULL, 0);
36 if (!obj)
37 return NULL;
38 return check_commit(obj, sha1, quiet);
41 struct commit *lookup_commit_reference(const unsigned char *sha1)
43 return lookup_commit_reference_gently(sha1, 0);
46 struct commit *lookup_commit_or_die(const unsigned char *sha1, const char *ref_name)
48 struct commit *c = lookup_commit_reference(sha1);
49 if (!c)
50 die(_("could not parse %s"), ref_name);
51 if (hashcmp(sha1, c->object.sha1)) {
52 warning(_("%s %s is not a commit!"),
53 ref_name, sha1_to_hex(sha1));
55 return c;
58 struct commit *lookup_commit(const unsigned char *sha1)
60 struct object *obj = lookup_object(sha1);
61 if (!obj)
62 return create_object(sha1, OBJ_COMMIT, alloc_commit_node());
63 if (!obj->type)
64 obj->type = OBJ_COMMIT;
65 return check_commit(obj, sha1, 0);
68 struct commit *lookup_commit_reference_by_name(const char *name)
70 unsigned char sha1[20];
71 struct commit *commit;
73 if (get_sha1_committish(name, sha1))
74 return NULL;
75 commit = lookup_commit_reference(sha1);
76 if (!commit || parse_commit(commit))
77 return NULL;
78 return commit;
81 static unsigned long parse_commit_date(const char *buf, const char *tail)
83 const char *dateptr;
85 if (buf + 6 >= tail)
86 return 0;
87 if (memcmp(buf, "author", 6))
88 return 0;
89 while (buf < tail && *buf++ != '\n')
90 /* nada */;
91 if (buf + 9 >= tail)
92 return 0;
93 if (memcmp(buf, "committer", 9))
94 return 0;
95 while (buf < tail && *buf++ != '>')
96 /* nada */;
97 if (buf >= tail)
98 return 0;
99 dateptr = buf;
100 while (buf < tail && *buf++ != '\n')
101 /* nada */;
102 if (buf >= tail)
103 return 0;
104 /* dateptr < buf && buf[-1] == '\n', so strtoul will stop at buf-1 */
105 return strtoul(dateptr, NULL, 10);
108 static struct commit_graft **commit_graft;
109 static int commit_graft_alloc, commit_graft_nr;
111 static int commit_graft_pos(const unsigned char *sha1)
113 int lo, hi;
114 lo = 0;
115 hi = commit_graft_nr;
116 while (lo < hi) {
117 int mi = (lo + hi) / 2;
118 struct commit_graft *graft = commit_graft[mi];
119 int cmp = hashcmp(sha1, graft->sha1);
120 if (!cmp)
121 return mi;
122 if (cmp < 0)
123 hi = mi;
124 else
125 lo = mi + 1;
127 return -lo - 1;
130 int register_commit_graft(struct commit_graft *graft, int ignore_dups)
132 int pos = commit_graft_pos(graft->sha1);
134 if (0 <= pos) {
135 if (ignore_dups)
136 free(graft);
137 else {
138 free(commit_graft[pos]);
139 commit_graft[pos] = graft;
141 return 1;
143 pos = -pos - 1;
144 if (commit_graft_alloc <= ++commit_graft_nr) {
145 commit_graft_alloc = alloc_nr(commit_graft_alloc);
146 commit_graft = xrealloc(commit_graft,
147 sizeof(*commit_graft) *
148 commit_graft_alloc);
150 if (pos < commit_graft_nr)
151 memmove(commit_graft + pos + 1,
152 commit_graft + pos,
153 (commit_graft_nr - pos - 1) *
154 sizeof(*commit_graft));
155 commit_graft[pos] = graft;
156 return 0;
159 struct commit_graft *read_graft_line(char *buf, int len)
161 /* The format is just "Commit Parent1 Parent2 ...\n" */
162 int i;
163 struct commit_graft *graft = NULL;
165 while (len && isspace(buf[len-1]))
166 buf[--len] = '\0';
167 if (buf[0] == '#' || buf[0] == '\0')
168 return NULL;
169 if ((len + 1) % 41)
170 goto bad_graft_data;
171 i = (len + 1) / 41 - 1;
172 graft = xmalloc(sizeof(*graft) + 20 * i);
173 graft->nr_parent = i;
174 if (get_sha1_hex(buf, graft->sha1))
175 goto bad_graft_data;
176 for (i = 40; i < len; i += 41) {
177 if (buf[i] != ' ')
178 goto bad_graft_data;
179 if (get_sha1_hex(buf + i + 1, graft->parent[i/41]))
180 goto bad_graft_data;
182 return graft;
184 bad_graft_data:
185 error("bad graft data: %s", buf);
186 free(graft);
187 return NULL;
190 static int read_graft_file(const char *graft_file)
192 FILE *fp = fopen(graft_file, "r");
193 char buf[1024];
194 if (!fp)
195 return -1;
196 while (fgets(buf, sizeof(buf), fp)) {
197 /* The format is just "Commit Parent1 Parent2 ...\n" */
198 int len = strlen(buf);
199 struct commit_graft *graft = read_graft_line(buf, len);
200 if (!graft)
201 continue;
202 if (register_commit_graft(graft, 1))
203 error("duplicate graft data: %s", buf);
205 fclose(fp);
206 return 0;
209 static void prepare_commit_graft(void)
211 static int commit_graft_prepared;
212 char *graft_file;
214 if (commit_graft_prepared)
215 return;
216 graft_file = get_graft_file();
217 read_graft_file(graft_file);
218 /* make sure shallows are read */
219 is_repository_shallow();
220 commit_graft_prepared = 1;
223 struct commit_graft *lookup_commit_graft(const unsigned char *sha1)
225 int pos;
226 prepare_commit_graft();
227 pos = commit_graft_pos(sha1);
228 if (pos < 0)
229 return NULL;
230 return commit_graft[pos];
233 int for_each_commit_graft(each_commit_graft_fn fn, void *cb_data)
235 int i, ret;
236 for (i = ret = 0; i < commit_graft_nr && !ret; i++)
237 ret = fn(commit_graft[i], cb_data);
238 return ret;
241 int unregister_shallow(const unsigned char *sha1)
243 int pos = commit_graft_pos(sha1);
244 if (pos < 0)
245 return -1;
246 if (pos + 1 < commit_graft_nr)
247 memmove(commit_graft + pos, commit_graft + pos + 1,
248 sizeof(struct commit_graft *)
249 * (commit_graft_nr - pos - 1));
250 commit_graft_nr--;
251 return 0;
254 int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long size)
256 const char *tail = buffer;
257 const char *bufptr = buffer;
258 unsigned char parent[20];
259 struct commit_list **pptr;
260 struct commit_graft *graft;
262 if (item->object.parsed)
263 return 0;
264 item->object.parsed = 1;
265 tail += size;
266 if (tail <= bufptr + 46 || memcmp(bufptr, "tree ", 5) || bufptr[45] != '\n')
267 return error("bogus commit object %s", sha1_to_hex(item->object.sha1));
268 if (get_sha1_hex(bufptr + 5, parent) < 0)
269 return error("bad tree pointer in commit %s",
270 sha1_to_hex(item->object.sha1));
271 item->tree = lookup_tree(parent);
272 bufptr += 46; /* "tree " + "hex sha1" + "\n" */
273 pptr = &item->parents;
275 graft = lookup_commit_graft(item->object.sha1);
276 while (bufptr + 48 < tail && !memcmp(bufptr, "parent ", 7)) {
277 struct commit *new_parent;
279 if (tail <= bufptr + 48 ||
280 get_sha1_hex(bufptr + 7, parent) ||
281 bufptr[47] != '\n')
282 return error("bad parents in commit %s", sha1_to_hex(item->object.sha1));
283 bufptr += 48;
285 * The clone is shallow if nr_parent < 0, and we must
286 * not traverse its real parents even when we unhide them.
288 if (graft && (graft->nr_parent < 0 || grafts_replace_parents))
289 continue;
290 new_parent = lookup_commit(parent);
291 if (new_parent)
292 pptr = &commit_list_insert(new_parent, pptr)->next;
294 if (graft) {
295 int i;
296 struct commit *new_parent;
297 for (i = 0; i < graft->nr_parent; i++) {
298 new_parent = lookup_commit(graft->parent[i]);
299 if (!new_parent)
300 continue;
301 pptr = &commit_list_insert(new_parent, pptr)->next;
304 item->date = parse_commit_date(bufptr, tail);
306 return 0;
309 int parse_commit(struct commit *item)
311 enum object_type type;
312 void *buffer;
313 unsigned long size;
314 int ret;
316 if (!item)
317 return -1;
318 if (item->object.parsed)
319 return 0;
320 buffer = read_sha1_file(item->object.sha1, &type, &size);
321 if (!buffer)
322 return error("Could not read %s",
323 sha1_to_hex(item->object.sha1));
324 if (type != OBJ_COMMIT) {
325 free(buffer);
326 return error("Object %s not a commit",
327 sha1_to_hex(item->object.sha1));
329 ret = parse_commit_buffer(item, buffer, size);
330 if (save_commit_buffer && !ret) {
331 item->buffer = buffer;
332 return 0;
334 free(buffer);
335 return ret;
338 int find_commit_subject(const char *commit_buffer, const char **subject)
340 const char *eol;
341 const char *p = commit_buffer;
343 while (*p && (*p != '\n' || p[1] != '\n'))
344 p++;
345 if (*p) {
346 p += 2;
347 for (eol = p; *eol && *eol != '\n'; eol++)
348 ; /* do nothing */
349 } else
350 eol = p;
352 *subject = p;
354 return eol - p;
357 struct commit_list *commit_list_insert(struct commit *item, struct commit_list **list_p)
359 struct commit_list *new_list = xmalloc(sizeof(struct commit_list));
360 new_list->item = item;
361 new_list->next = *list_p;
362 *list_p = new_list;
363 return new_list;
366 unsigned commit_list_count(const struct commit_list *l)
368 unsigned c = 0;
369 for (; l; l = l->next )
370 c++;
371 return c;
374 void free_commit_list(struct commit_list *list)
376 while (list) {
377 struct commit_list *temp = list;
378 list = temp->next;
379 free(temp);
383 struct commit_list * commit_list_insert_by_date(struct commit *item, struct commit_list **list)
385 struct commit_list **pp = list;
386 struct commit_list *p;
387 while ((p = *pp) != NULL) {
388 if (p->item->date < item->date) {
389 break;
391 pp = &p->next;
393 return commit_list_insert(item, pp);
396 static int commit_list_compare_by_date(const void *a, const void *b)
398 unsigned long a_date = ((const struct commit_list *)a)->item->date;
399 unsigned long b_date = ((const struct commit_list *)b)->item->date;
400 if (a_date < b_date)
401 return 1;
402 if (a_date > b_date)
403 return -1;
404 return 0;
407 static void *commit_list_get_next(const void *a)
409 return ((const struct commit_list *)a)->next;
412 static void commit_list_set_next(void *a, void *next)
414 ((struct commit_list *)a)->next = next;
417 void commit_list_sort_by_date(struct commit_list **list)
419 *list = llist_mergesort(*list, commit_list_get_next, commit_list_set_next,
420 commit_list_compare_by_date);
423 struct commit *pop_most_recent_commit(struct commit_list **list,
424 unsigned int mark)
426 struct commit *ret = (*list)->item;
427 struct commit_list *parents = ret->parents;
428 struct commit_list *old = *list;
430 *list = (*list)->next;
431 free(old);
433 while (parents) {
434 struct commit *commit = parents->item;
435 if (!parse_commit(commit) && !(commit->object.flags & mark)) {
436 commit->object.flags |= mark;
437 commit_list_insert_by_date(commit, list);
439 parents = parents->next;
441 return ret;
444 static void clear_commit_marks_1(struct commit_list **plist,
445 struct commit *commit, unsigned int mark)
447 while (commit) {
448 struct commit_list *parents;
450 if (!(mark & commit->object.flags))
451 return;
453 commit->object.flags &= ~mark;
455 parents = commit->parents;
456 if (!parents)
457 return;
459 while ((parents = parents->next))
460 commit_list_insert(parents->item, plist);
462 commit = commit->parents->item;
466 void clear_commit_marks(struct commit *commit, unsigned int mark)
468 struct commit_list *list = NULL;
469 commit_list_insert(commit, &list);
470 while (list)
471 clear_commit_marks_1(&list, pop_commit(&list), mark);
474 void clear_commit_marks_for_object_array(struct object_array *a, unsigned mark)
476 struct object *object;
477 struct commit *commit;
478 unsigned int i;
480 for (i = 0; i < a->nr; i++) {
481 object = a->objects[i].item;
482 commit = lookup_commit_reference_gently(object->sha1, 1);
483 if (commit)
484 clear_commit_marks(commit, mark);
488 struct commit *pop_commit(struct commit_list **stack)
490 struct commit_list *top = *stack;
491 struct commit *item = top ? top->item : NULL;
493 if (top) {
494 *stack = top->next;
495 free(top);
497 return item;
501 * Performs an in-place topological sort on the list supplied.
503 void sort_in_topological_order(struct commit_list ** list, int lifo)
505 struct commit_list *next, *orig = *list;
506 struct commit_list *work, **insert;
507 struct commit_list **pptr;
509 if (!orig)
510 return;
511 *list = NULL;
513 /* Mark them and clear the indegree */
514 for (next = orig; next; next = next->next) {
515 struct commit *commit = next->item;
516 commit->indegree = 1;
519 /* update the indegree */
520 for (next = orig; next; next = next->next) {
521 struct commit_list * parents = next->item->parents;
522 while (parents) {
523 struct commit *parent = parents->item;
525 if (parent->indegree)
526 parent->indegree++;
527 parents = parents->next;
532 * find the tips
534 * tips are nodes not reachable from any other node in the list
536 * the tips serve as a starting set for the work queue.
538 work = NULL;
539 insert = &work;
540 for (next = orig; next; next = next->next) {
541 struct commit *commit = next->item;
543 if (commit->indegree == 1)
544 insert = &commit_list_insert(commit, insert)->next;
547 /* process the list in topological order */
548 if (!lifo)
549 commit_list_sort_by_date(&work);
551 pptr = list;
552 *list = NULL;
553 while (work) {
554 struct commit *commit;
555 struct commit_list *parents, *work_item;
557 work_item = work;
558 work = work_item->next;
559 work_item->next = NULL;
561 commit = work_item->item;
562 for (parents = commit->parents; parents ; parents = parents->next) {
563 struct commit *parent = parents->item;
565 if (!parent->indegree)
566 continue;
569 * parents are only enqueued for emission
570 * when all their children have been emitted thereby
571 * guaranteeing topological order.
573 if (--parent->indegree == 1) {
574 if (!lifo)
575 commit_list_insert_by_date(parent, &work);
576 else
577 commit_list_insert(parent, &work);
581 * work_item is a commit all of whose children
582 * have already been emitted. we can emit it now.
584 commit->indegree = 0;
585 *pptr = work_item;
586 pptr = &work_item->next;
590 /* merge-base stuff */
592 /* bits #0..15 in revision.h */
593 #define PARENT1 (1u<<16)
594 #define PARENT2 (1u<<17)
595 #define STALE (1u<<18)
596 #define RESULT (1u<<19)
598 static const unsigned all_flags = (PARENT1 | PARENT2 | STALE | RESULT);
600 static struct commit *interesting(struct commit_list *list)
602 while (list) {
603 struct commit *commit = list->item;
604 list = list->next;
605 if (commit->object.flags & STALE)
606 continue;
607 return commit;
609 return NULL;
612 /* all input commits in one and twos[] must have been parsed! */
613 static struct commit_list *paint_down_to_common(struct commit *one, int n, struct commit **twos)
615 struct commit_list *list = NULL;
616 struct commit_list *result = NULL;
617 int i;
619 one->object.flags |= PARENT1;
620 commit_list_insert_by_date(one, &list);
621 if (!n)
622 return list;
623 for (i = 0; i < n; i++) {
624 twos[i]->object.flags |= PARENT2;
625 commit_list_insert_by_date(twos[i], &list);
628 while (interesting(list)) {
629 struct commit *commit;
630 struct commit_list *parents;
631 struct commit_list *next;
632 int flags;
634 commit = list->item;
635 next = list->next;
636 free(list);
637 list = next;
639 flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
640 if (flags == (PARENT1 | PARENT2)) {
641 if (!(commit->object.flags & RESULT)) {
642 commit->object.flags |= RESULT;
643 commit_list_insert_by_date(commit, &result);
645 /* Mark parents of a found merge stale */
646 flags |= STALE;
648 parents = commit->parents;
649 while (parents) {
650 struct commit *p = parents->item;
651 parents = parents->next;
652 if ((p->object.flags & flags) == flags)
653 continue;
654 if (parse_commit(p))
655 return NULL;
656 p->object.flags |= flags;
657 commit_list_insert_by_date(p, &list);
661 free_commit_list(list);
662 return result;
665 static struct commit_list *merge_bases_many(struct commit *one, int n, struct commit **twos)
667 struct commit_list *list = NULL;
668 struct commit_list *result = NULL;
669 int i;
671 for (i = 0; i < n; i++) {
672 if (one == twos[i])
674 * We do not mark this even with RESULT so we do not
675 * have to clean it up.
677 return commit_list_insert(one, &result);
680 if (parse_commit(one))
681 return NULL;
682 for (i = 0; i < n; i++) {
683 if (parse_commit(twos[i]))
684 return NULL;
687 list = paint_down_to_common(one, n, twos);
689 while (list) {
690 struct commit_list *next = list->next;
691 if (!(list->item->object.flags & STALE))
692 commit_list_insert_by_date(list->item, &result);
693 free(list);
694 list = next;
696 return result;
699 struct commit_list *get_octopus_merge_bases(struct commit_list *in)
701 struct commit_list *i, *j, *k, *ret = NULL;
702 struct commit_list **pptr = &ret;
704 for (i = in; i; i = i->next) {
705 if (!ret)
706 pptr = &commit_list_insert(i->item, pptr)->next;
707 else {
708 struct commit_list *new = NULL, *end = NULL;
710 for (j = ret; j; j = j->next) {
711 struct commit_list *bases;
712 bases = get_merge_bases(i->item, j->item, 1);
713 if (!new)
714 new = bases;
715 else
716 end->next = bases;
717 for (k = bases; k; k = k->next)
718 end = k;
720 ret = new;
723 return ret;
726 static int remove_redundant(struct commit **array, int cnt)
729 * Some commit in the array may be an ancestor of
730 * another commit. Move such commit to the end of
731 * the array, and return the number of commits that
732 * are independent from each other.
734 struct commit **work;
735 unsigned char *redundant;
736 int *filled_index;
737 int i, j, filled;
739 work = xcalloc(cnt, sizeof(*work));
740 redundant = xcalloc(cnt, 1);
741 filled_index = xmalloc(sizeof(*filled_index) * (cnt - 1));
743 for (i = 0; i < cnt; i++)
744 parse_commit(array[i]);
745 for (i = 0; i < cnt; i++) {
746 struct commit_list *common;
748 if (redundant[i])
749 continue;
750 for (j = filled = 0; j < cnt; j++) {
751 if (i == j || redundant[j])
752 continue;
753 filled_index[filled] = j;
754 work[filled++] = array[j];
756 common = paint_down_to_common(array[i], filled, work);
757 if (array[i]->object.flags & PARENT2)
758 redundant[i] = 1;
759 for (j = 0; j < filled; j++)
760 if (work[j]->object.flags & PARENT1)
761 redundant[filled_index[j]] = 1;
762 clear_commit_marks(array[i], all_flags);
763 for (j = 0; j < filled; j++)
764 clear_commit_marks(work[j], all_flags);
765 free_commit_list(common);
768 /* Now collect the result */
769 memcpy(work, array, sizeof(*array) * cnt);
770 for (i = filled = 0; i < cnt; i++)
771 if (!redundant[i])
772 array[filled++] = work[i];
773 for (j = filled, i = 0; i < cnt; i++)
774 if (redundant[i])
775 array[j++] = work[i];
776 free(work);
777 free(redundant);
778 free(filled_index);
779 return filled;
782 struct commit_list *get_merge_bases_many(struct commit *one,
783 int n,
784 struct commit **twos,
785 int cleanup)
787 struct commit_list *list;
788 struct commit **rslt;
789 struct commit_list *result;
790 int cnt, i;
792 result = merge_bases_many(one, n, twos);
793 for (i = 0; i < n; i++) {
794 if (one == twos[i])
795 return result;
797 if (!result || !result->next) {
798 if (cleanup) {
799 clear_commit_marks(one, all_flags);
800 for (i = 0; i < n; i++)
801 clear_commit_marks(twos[i], all_flags);
803 return result;
806 /* There are more than one */
807 cnt = 0;
808 list = result;
809 while (list) {
810 list = list->next;
811 cnt++;
813 rslt = xcalloc(cnt, sizeof(*rslt));
814 for (list = result, i = 0; list; list = list->next)
815 rslt[i++] = list->item;
816 free_commit_list(result);
818 clear_commit_marks(one, all_flags);
819 for (i = 0; i < n; i++)
820 clear_commit_marks(twos[i], all_flags);
822 cnt = remove_redundant(rslt, cnt);
823 result = NULL;
824 for (i = 0; i < cnt; i++)
825 commit_list_insert_by_date(rslt[i], &result);
826 free(rslt);
827 return result;
830 struct commit_list *get_merge_bases(struct commit *one, struct commit *two,
831 int cleanup)
833 return get_merge_bases_many(one, 1, &two, cleanup);
837 * Is "commit" a decendant of one of the elements on the "with_commit" list?
839 int is_descendant_of(struct commit *commit, struct commit_list *with_commit)
841 if (!with_commit)
842 return 1;
843 while (with_commit) {
844 struct commit *other;
846 other = with_commit->item;
847 with_commit = with_commit->next;
848 if (in_merge_bases(other, commit))
849 return 1;
851 return 0;
855 * Is "commit" an ancestor of (i.e. reachable from) the "reference"?
857 int in_merge_bases(struct commit *commit, struct commit *reference)
859 struct commit_list *bases;
860 int ret = 0;
862 if (parse_commit(commit) || parse_commit(reference))
863 return ret;
865 bases = paint_down_to_common(commit, 1, &reference);
866 if (commit->object.flags & PARENT2)
867 ret = 1;
868 clear_commit_marks(commit, all_flags);
869 clear_commit_marks(reference, all_flags);
870 free_commit_list(bases);
871 return ret;
874 struct commit_list *reduce_heads(struct commit_list *heads)
876 struct commit_list *p;
877 struct commit_list *result = NULL, **tail = &result;
878 struct commit **array;
879 int num_head, i;
881 if (!heads)
882 return NULL;
884 /* Uniquify */
885 for (p = heads; p; p = p->next)
886 p->item->object.flags &= ~STALE;
887 for (p = heads, num_head = 0; p; p = p->next) {
888 if (p->item->object.flags & STALE)
889 continue;
890 p->item->object.flags |= STALE;
891 num_head++;
893 array = xcalloc(sizeof(*array), num_head);
894 for (p = heads, i = 0; p; p = p->next) {
895 if (p->item->object.flags & STALE) {
896 array[i++] = p->item;
897 p->item->object.flags &= ~STALE;
900 num_head = remove_redundant(array, num_head);
901 for (i = 0; i < num_head; i++)
902 tail = &commit_list_insert(array[i], tail)->next;
903 return result;
906 static const char gpg_sig_header[] = "gpgsig";
907 static const int gpg_sig_header_len = sizeof(gpg_sig_header) - 1;
909 static int do_sign_commit(struct strbuf *buf, const char *keyid)
911 struct strbuf sig = STRBUF_INIT;
912 int inspos, copypos;
914 /* find the end of the header */
915 inspos = strstr(buf->buf, "\n\n") - buf->buf + 1;
917 if (!keyid || !*keyid)
918 keyid = get_signing_key();
919 if (sign_buffer(buf, &sig, keyid)) {
920 strbuf_release(&sig);
921 return -1;
924 for (copypos = 0; sig.buf[copypos]; ) {
925 const char *bol = sig.buf + copypos;
926 const char *eol = strchrnul(bol, '\n');
927 int len = (eol - bol) + !!*eol;
929 if (!copypos) {
930 strbuf_insert(buf, inspos, gpg_sig_header, gpg_sig_header_len);
931 inspos += gpg_sig_header_len;
933 strbuf_insert(buf, inspos++, " ", 1);
934 strbuf_insert(buf, inspos, bol, len);
935 inspos += len;
936 copypos += len;
938 strbuf_release(&sig);
939 return 0;
942 int parse_signed_commit(const unsigned char *sha1,
943 struct strbuf *payload, struct strbuf *signature)
945 unsigned long size;
946 enum object_type type;
947 char *buffer = read_sha1_file(sha1, &type, &size);
948 int in_signature, saw_signature = -1;
949 char *line, *tail;
951 if (!buffer || type != OBJ_COMMIT)
952 goto cleanup;
954 line = buffer;
955 tail = buffer + size;
956 in_signature = 0;
957 saw_signature = 0;
958 while (line < tail) {
959 const char *sig = NULL;
960 char *next = memchr(line, '\n', tail - line);
962 next = next ? next + 1 : tail;
963 if (in_signature && line[0] == ' ')
964 sig = line + 1;
965 else if (!prefixcmp(line, gpg_sig_header) &&
966 line[gpg_sig_header_len] == ' ')
967 sig = line + gpg_sig_header_len + 1;
968 if (sig) {
969 strbuf_add(signature, sig, next - sig);
970 saw_signature = 1;
971 in_signature = 1;
972 } else {
973 if (*line == '\n')
974 /* dump the whole remainder of the buffer */
975 next = tail;
976 strbuf_add(payload, line, next - line);
977 in_signature = 0;
979 line = next;
981 cleanup:
982 free(buffer);
983 return saw_signature;
986 static void handle_signed_tag(struct commit *parent, struct commit_extra_header ***tail)
988 struct merge_remote_desc *desc;
989 struct commit_extra_header *mergetag;
990 char *buf;
991 unsigned long size, len;
992 enum object_type type;
994 desc = merge_remote_util(parent);
995 if (!desc || !desc->obj)
996 return;
997 buf = read_sha1_file(desc->obj->sha1, &type, &size);
998 if (!buf || type != OBJ_TAG)
999 goto free_return;
1000 len = parse_signature(buf, size);
1001 if (size == len)
1002 goto free_return;
1004 * We could verify this signature and either omit the tag when
1005 * it does not validate, but the integrator may not have the
1006 * public key of the signer of the tag he is merging, while a
1007 * later auditor may have it while auditing, so let's not run
1008 * verify-signed-buffer here for now...
1010 * if (verify_signed_buffer(buf, len, buf + len, size - len, ...))
1011 * warn("warning: signed tag unverified.");
1013 mergetag = xcalloc(1, sizeof(*mergetag));
1014 mergetag->key = xstrdup("mergetag");
1015 mergetag->value = buf;
1016 mergetag->len = size;
1018 **tail = mergetag;
1019 *tail = &mergetag->next;
1020 return;
1022 free_return:
1023 free(buf);
1026 void append_merge_tag_headers(struct commit_list *parents,
1027 struct commit_extra_header ***tail)
1029 while (parents) {
1030 struct commit *parent = parents->item;
1031 handle_signed_tag(parent, tail);
1032 parents = parents->next;
1036 static void add_extra_header(struct strbuf *buffer,
1037 struct commit_extra_header *extra)
1039 strbuf_addstr(buffer, extra->key);
1040 if (extra->len)
1041 strbuf_add_lines(buffer, " ", extra->value, extra->len);
1042 else
1043 strbuf_addch(buffer, '\n');
1046 struct commit_extra_header *read_commit_extra_headers(struct commit *commit,
1047 const char **exclude)
1049 struct commit_extra_header *extra = NULL;
1050 unsigned long size;
1051 enum object_type type;
1052 char *buffer = read_sha1_file(commit->object.sha1, &type, &size);
1053 if (buffer && type == OBJ_COMMIT)
1054 extra = read_commit_extra_header_lines(buffer, size, exclude);
1055 free(buffer);
1056 return extra;
1059 static inline int standard_header_field(const char *field, size_t len)
1061 return ((len == 4 && !memcmp(field, "tree ", 5)) ||
1062 (len == 6 && !memcmp(field, "parent ", 7)) ||
1063 (len == 6 && !memcmp(field, "author ", 7)) ||
1064 (len == 9 && !memcmp(field, "committer ", 10)) ||
1065 (len == 8 && !memcmp(field, "encoding ", 9)));
1068 static int excluded_header_field(const char *field, size_t len, const char **exclude)
1070 if (!exclude)
1071 return 0;
1073 while (*exclude) {
1074 size_t xlen = strlen(*exclude);
1075 if (len == xlen &&
1076 !memcmp(field, *exclude, xlen) && field[xlen] == ' ')
1077 return 1;
1078 exclude++;
1080 return 0;
1083 static struct commit_extra_header *read_commit_extra_header_lines(
1084 const char *buffer, size_t size,
1085 const char **exclude)
1087 struct commit_extra_header *extra = NULL, **tail = &extra, *it = NULL;
1088 const char *line, *next, *eof, *eob;
1089 struct strbuf buf = STRBUF_INIT;
1091 for (line = buffer, eob = line + size;
1092 line < eob && *line != '\n';
1093 line = next) {
1094 next = memchr(line, '\n', eob - line);
1095 next = next ? next + 1 : eob;
1096 if (*line == ' ') {
1097 /* continuation */
1098 if (it)
1099 strbuf_add(&buf, line + 1, next - (line + 1));
1100 continue;
1102 if (it)
1103 it->value = strbuf_detach(&buf, &it->len);
1104 strbuf_reset(&buf);
1105 it = NULL;
1107 eof = strchr(line, ' ');
1108 if (next <= eof)
1109 eof = next;
1111 if (standard_header_field(line, eof - line) ||
1112 excluded_header_field(line, eof - line, exclude))
1113 continue;
1115 it = xcalloc(1, sizeof(*it));
1116 it->key = xmemdupz(line, eof-line);
1117 *tail = it;
1118 tail = &it->next;
1119 if (eof + 1 < next)
1120 strbuf_add(&buf, eof + 1, next - (eof + 1));
1122 if (it)
1123 it->value = strbuf_detach(&buf, &it->len);
1124 return extra;
1127 void free_commit_extra_headers(struct commit_extra_header *extra)
1129 while (extra) {
1130 struct commit_extra_header *next = extra->next;
1131 free(extra->key);
1132 free(extra->value);
1133 free(extra);
1134 extra = next;
1138 int commit_tree(const struct strbuf *msg, unsigned char *tree,
1139 struct commit_list *parents, unsigned char *ret,
1140 const char *author, const char *sign_commit)
1142 struct commit_extra_header *extra = NULL, **tail = &extra;
1143 int result;
1145 append_merge_tag_headers(parents, &tail);
1146 result = commit_tree_extended(msg, tree, parents, ret,
1147 author, sign_commit, extra);
1148 free_commit_extra_headers(extra);
1149 return result;
1152 static int find_invalid_utf8(const char *buf, int len)
1154 int offset = 0;
1156 while (len) {
1157 unsigned char c = *buf++;
1158 int bytes, bad_offset;
1160 len--;
1161 offset++;
1163 /* Simple US-ASCII? No worries. */
1164 if (c < 0x80)
1165 continue;
1167 bad_offset = offset-1;
1170 * Count how many more high bits set: that's how
1171 * many more bytes this sequence should have.
1173 bytes = 0;
1174 while (c & 0x40) {
1175 c <<= 1;
1176 bytes++;
1179 /* Must be between 1 and 5 more bytes */
1180 if (bytes < 1 || bytes > 5)
1181 return bad_offset;
1183 /* Do we *have* that many bytes? */
1184 if (len < bytes)
1185 return bad_offset;
1187 offset += bytes;
1188 len -= bytes;
1190 /* And verify that they are good continuation bytes */
1191 do {
1192 if ((*buf++ & 0xc0) != 0x80)
1193 return bad_offset;
1194 } while (--bytes);
1196 /* We could/should check the value and length here too */
1198 return -1;
1202 * This verifies that the buffer is in proper utf8 format.
1204 * If it isn't, it assumes any non-utf8 characters are Latin1,
1205 * and does the conversion.
1207 * Fixme: we should probably also disallow overlong forms and
1208 * invalid characters. But we don't do that currently.
1210 static int verify_utf8(struct strbuf *buf)
1212 int ok = 1;
1213 long pos = 0;
1215 for (;;) {
1216 int bad;
1217 unsigned char c;
1218 unsigned char replace[2];
1220 bad = find_invalid_utf8(buf->buf + pos, buf->len - pos);
1221 if (bad < 0)
1222 return ok;
1223 pos += bad;
1224 ok = 0;
1225 c = buf->buf[pos];
1226 strbuf_remove(buf, pos, 1);
1228 /* We know 'c' must be in the range 128-255 */
1229 replace[0] = 0xc0 + (c >> 6);
1230 replace[1] = 0x80 + (c & 0x3f);
1231 strbuf_insert(buf, pos, replace, 2);
1232 pos += 2;
1236 static const char commit_utf8_warn[] =
1237 "Warning: commit message did not conform to UTF-8.\n"
1238 "You may want to amend it after fixing the message, or set the config\n"
1239 "variable i18n.commitencoding to the encoding your project uses.\n";
1241 int commit_tree_extended(const struct strbuf *msg, unsigned char *tree,
1242 struct commit_list *parents, unsigned char *ret,
1243 const char *author, const char *sign_commit,
1244 struct commit_extra_header *extra)
1246 int result;
1247 int encoding_is_utf8;
1248 struct strbuf buffer;
1250 assert_sha1_type(tree, OBJ_TREE);
1252 if (memchr(msg->buf, '\0', msg->len))
1253 return error("a NUL byte in commit log message not allowed.");
1255 /* Not having i18n.commitencoding is the same as having utf-8 */
1256 encoding_is_utf8 = is_encoding_utf8(git_commit_encoding);
1258 strbuf_init(&buffer, 8192); /* should avoid reallocs for the headers */
1259 strbuf_addf(&buffer, "tree %s\n", sha1_to_hex(tree));
1262 * NOTE! This ordering means that the same exact tree merged with a
1263 * different order of parents will be a _different_ changeset even
1264 * if everything else stays the same.
1266 while (parents) {
1267 struct commit_list *next = parents->next;
1268 struct commit *parent = parents->item;
1270 strbuf_addf(&buffer, "parent %s\n",
1271 sha1_to_hex(parent->object.sha1));
1272 free(parents);
1273 parents = next;
1276 /* Person/date information */
1277 if (!author)
1278 author = git_author_info(IDENT_STRICT);
1279 strbuf_addf(&buffer, "author %s\n", author);
1280 strbuf_addf(&buffer, "committer %s\n", git_committer_info(IDENT_STRICT));
1281 if (!encoding_is_utf8)
1282 strbuf_addf(&buffer, "encoding %s\n", git_commit_encoding);
1284 while (extra) {
1285 add_extra_header(&buffer, extra);
1286 extra = extra->next;
1288 strbuf_addch(&buffer, '\n');
1290 /* And add the comment */
1291 strbuf_addbuf(&buffer, msg);
1293 /* And check the encoding */
1294 if (encoding_is_utf8 && !verify_utf8(&buffer))
1295 fprintf(stderr, commit_utf8_warn);
1297 if (sign_commit && do_sign_commit(&buffer, sign_commit))
1298 return -1;
1300 result = write_sha1_file(buffer.buf, buffer.len, commit_type, ret);
1301 strbuf_release(&buffer);
1302 return result;
1305 struct commit *get_merge_parent(const char *name)
1307 struct object *obj;
1308 struct commit *commit;
1309 unsigned char sha1[20];
1310 if (get_sha1(name, sha1))
1311 return NULL;
1312 obj = parse_object(sha1);
1313 commit = (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
1314 if (commit && !commit->util) {
1315 struct merge_remote_desc *desc;
1316 desc = xmalloc(sizeof(*desc));
1317 desc->obj = obj;
1318 desc->name = strdup(name);
1319 commit->util = desc;
1321 return commit;
1325 * Append a commit to the end of the commit_list.
1327 * next starts by pointing to the variable that holds the head of an
1328 * empty commit_list, and is updated to point to the "next" field of
1329 * the last item on the list as new commits are appended.
1331 * Usage example:
1333 * struct commit_list *list;
1334 * struct commit_list **next = &list;
1336 * next = commit_list_append(c1, next);
1337 * next = commit_list_append(c2, next);
1338 * assert(commit_list_count(list) == 2);
1339 * return list;
1341 struct commit_list **commit_list_append(struct commit *commit,
1342 struct commit_list **next)
1344 struct commit_list *new = xmalloc(sizeof(struct commit_list));
1345 new->item = commit;
1346 *next = new;
1347 new->next = NULL;
1348 return &new->next;
1351 void print_commit_list(struct commit_list *list,
1352 const char *format_cur,
1353 const char *format_last)
1355 for ( ; list; list = list->next) {
1356 const char *format = list->next ? format_cur : format_last;
1357 printf(format, sha1_to_hex(list->item->object.sha1));