Merge branch 'ye/doc-http-proto' into maint
[git.git] / commit.c
blob4ff8077dbfbc6cdd6c14728a3d33a78d075c236f
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 struct commit_buffer {
249 void *buffer;
250 unsigned long size;
252 define_commit_slab(buffer_slab, struct commit_buffer);
253 static struct buffer_slab buffer_slab = COMMIT_SLAB_INIT(1, buffer_slab);
255 void set_commit_buffer(struct commit *commit, void *buffer, unsigned long size)
257 struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
258 v->buffer = buffer;
259 v->size = size;
262 const void *get_cached_commit_buffer(const struct commit *commit, unsigned long *sizep)
264 struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
265 if (sizep)
266 *sizep = v->size;
267 return v->buffer;
270 const void *get_commit_buffer(const struct commit *commit, unsigned long *sizep)
272 const void *ret = get_cached_commit_buffer(commit, sizep);
273 if (!ret) {
274 enum object_type type;
275 unsigned long size;
276 ret = read_sha1_file(commit->object.sha1, &type, &size);
277 if (!ret)
278 die("cannot read commit object %s",
279 sha1_to_hex(commit->object.sha1));
280 if (type != OBJ_COMMIT)
281 die("expected commit for %s, got %s",
282 sha1_to_hex(commit->object.sha1), typename(type));
283 if (sizep)
284 *sizep = size;
286 return ret;
289 void unuse_commit_buffer(const struct commit *commit, const void *buffer)
291 struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
292 if (v->buffer != buffer)
293 free((void *)buffer);
296 void free_commit_buffer(struct commit *commit)
298 struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
299 free(v->buffer);
300 v->buffer = NULL;
301 v->size = 0;
304 const void *detach_commit_buffer(struct commit *commit, unsigned long *sizep)
306 struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
307 void *ret;
309 ret = v->buffer;
310 if (sizep)
311 *sizep = v->size;
313 v->buffer = NULL;
314 v->size = 0;
315 return ret;
318 int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long size)
320 const char *tail = buffer;
321 const char *bufptr = buffer;
322 unsigned char parent[20];
323 struct commit_list **pptr;
324 struct commit_graft *graft;
326 if (item->object.parsed)
327 return 0;
328 item->object.parsed = 1;
329 tail += size;
330 if (tail <= bufptr + 46 || memcmp(bufptr, "tree ", 5) || bufptr[45] != '\n')
331 return error("bogus commit object %s", sha1_to_hex(item->object.sha1));
332 if (get_sha1_hex(bufptr + 5, parent) < 0)
333 return error("bad tree pointer in commit %s",
334 sha1_to_hex(item->object.sha1));
335 item->tree = lookup_tree(parent);
336 bufptr += 46; /* "tree " + "hex sha1" + "\n" */
337 pptr = &item->parents;
339 graft = lookup_commit_graft(item->object.sha1);
340 while (bufptr + 48 < tail && !memcmp(bufptr, "parent ", 7)) {
341 struct commit *new_parent;
343 if (tail <= bufptr + 48 ||
344 get_sha1_hex(bufptr + 7, parent) ||
345 bufptr[47] != '\n')
346 return error("bad parents in commit %s", sha1_to_hex(item->object.sha1));
347 bufptr += 48;
349 * The clone is shallow if nr_parent < 0, and we must
350 * not traverse its real parents even when we unhide them.
352 if (graft && (graft->nr_parent < 0 || grafts_replace_parents))
353 continue;
354 new_parent = lookup_commit(parent);
355 if (new_parent)
356 pptr = &commit_list_insert(new_parent, pptr)->next;
358 if (graft) {
359 int i;
360 struct commit *new_parent;
361 for (i = 0; i < graft->nr_parent; i++) {
362 new_parent = lookup_commit(graft->parent[i]);
363 if (!new_parent)
364 continue;
365 pptr = &commit_list_insert(new_parent, pptr)->next;
368 item->date = parse_commit_date(bufptr, tail);
370 return 0;
373 int parse_commit(struct commit *item)
375 enum object_type type;
376 void *buffer;
377 unsigned long size;
378 int ret;
380 if (!item)
381 return -1;
382 if (item->object.parsed)
383 return 0;
384 buffer = read_sha1_file(item->object.sha1, &type, &size);
385 if (!buffer)
386 return error("Could not read %s",
387 sha1_to_hex(item->object.sha1));
388 if (type != OBJ_COMMIT) {
389 free(buffer);
390 return error("Object %s not a commit",
391 sha1_to_hex(item->object.sha1));
393 ret = parse_commit_buffer(item, buffer, size);
394 if (save_commit_buffer && !ret) {
395 set_commit_buffer(item, buffer, size);
396 return 0;
398 free(buffer);
399 return ret;
402 void parse_commit_or_die(struct commit *item)
404 if (parse_commit(item))
405 die("unable to parse commit %s",
406 item ? sha1_to_hex(item->object.sha1) : "(null)");
409 int find_commit_subject(const char *commit_buffer, const char **subject)
411 const char *eol;
412 const char *p = commit_buffer;
414 while (*p && (*p != '\n' || p[1] != '\n'))
415 p++;
416 if (*p) {
417 p += 2;
418 for (eol = p; *eol && *eol != '\n'; eol++)
419 ; /* do nothing */
420 } else
421 eol = p;
423 *subject = p;
425 return eol - p;
428 struct commit_list *commit_list_insert(struct commit *item, struct commit_list **list_p)
430 struct commit_list *new_list = xmalloc(sizeof(struct commit_list));
431 new_list->item = item;
432 new_list->next = *list_p;
433 *list_p = new_list;
434 return new_list;
437 unsigned commit_list_count(const struct commit_list *l)
439 unsigned c = 0;
440 for (; l; l = l->next )
441 c++;
442 return c;
445 struct commit_list *copy_commit_list(struct commit_list *list)
447 struct commit_list *head = NULL;
448 struct commit_list **pp = &head;
449 while (list) {
450 struct commit_list *new;
451 new = xmalloc(sizeof(struct commit_list));
452 new->item = list->item;
453 new->next = NULL;
454 *pp = new;
455 pp = &new->next;
456 list = list->next;
458 return head;
461 void free_commit_list(struct commit_list *list)
463 while (list) {
464 struct commit_list *temp = list;
465 list = temp->next;
466 free(temp);
470 struct commit_list * commit_list_insert_by_date(struct commit *item, struct commit_list **list)
472 struct commit_list **pp = list;
473 struct commit_list *p;
474 while ((p = *pp) != NULL) {
475 if (p->item->date < item->date) {
476 break;
478 pp = &p->next;
480 return commit_list_insert(item, pp);
483 static int commit_list_compare_by_date(const void *a, const void *b)
485 unsigned long a_date = ((const struct commit_list *)a)->item->date;
486 unsigned long b_date = ((const struct commit_list *)b)->item->date;
487 if (a_date < b_date)
488 return 1;
489 if (a_date > b_date)
490 return -1;
491 return 0;
494 static void *commit_list_get_next(const void *a)
496 return ((const struct commit_list *)a)->next;
499 static void commit_list_set_next(void *a, void *next)
501 ((struct commit_list *)a)->next = next;
504 void commit_list_sort_by_date(struct commit_list **list)
506 *list = llist_mergesort(*list, commit_list_get_next, commit_list_set_next,
507 commit_list_compare_by_date);
510 struct commit *pop_most_recent_commit(struct commit_list **list,
511 unsigned int mark)
513 struct commit *ret = (*list)->item;
514 struct commit_list *parents = ret->parents;
515 struct commit_list *old = *list;
517 *list = (*list)->next;
518 free(old);
520 while (parents) {
521 struct commit *commit = parents->item;
522 if (!parse_commit(commit) && !(commit->object.flags & mark)) {
523 commit->object.flags |= mark;
524 commit_list_insert_by_date(commit, list);
526 parents = parents->next;
528 return ret;
531 static void clear_commit_marks_1(struct commit_list **plist,
532 struct commit *commit, unsigned int mark)
534 while (commit) {
535 struct commit_list *parents;
537 if (!(mark & commit->object.flags))
538 return;
540 commit->object.flags &= ~mark;
542 parents = commit->parents;
543 if (!parents)
544 return;
546 while ((parents = parents->next))
547 commit_list_insert(parents->item, plist);
549 commit = commit->parents->item;
553 void clear_commit_marks_many(int nr, struct commit **commit, unsigned int mark)
555 struct commit_list *list = NULL;
557 while (nr--) {
558 commit_list_insert(*commit, &list);
559 commit++;
561 while (list)
562 clear_commit_marks_1(&list, pop_commit(&list), mark);
565 void clear_commit_marks(struct commit *commit, unsigned int mark)
567 clear_commit_marks_many(1, &commit, mark);
570 void clear_commit_marks_for_object_array(struct object_array *a, unsigned mark)
572 struct object *object;
573 struct commit *commit;
574 unsigned int i;
576 for (i = 0; i < a->nr; i++) {
577 object = a->objects[i].item;
578 commit = lookup_commit_reference_gently(object->sha1, 1);
579 if (commit)
580 clear_commit_marks(commit, mark);
584 struct commit *pop_commit(struct commit_list **stack)
586 struct commit_list *top = *stack;
587 struct commit *item = top ? top->item : NULL;
589 if (top) {
590 *stack = top->next;
591 free(top);
593 return item;
597 * Topological sort support
600 /* count number of children that have not been emitted */
601 define_commit_slab(indegree_slab, int);
603 /* record author-date for each commit object */
604 define_commit_slab(author_date_slab, unsigned long);
606 static void record_author_date(struct author_date_slab *author_date,
607 struct commit *commit)
609 const char *buf, *line_end, *ident_line;
610 const char *buffer = get_commit_buffer(commit, NULL);
611 struct ident_split ident;
612 char *date_end;
613 unsigned long date;
615 for (buf = buffer; buf; buf = line_end + 1) {
616 line_end = strchrnul(buf, '\n');
617 ident_line = skip_prefix(buf, "author ");
618 if (!ident_line) {
619 if (!line_end[0] || line_end[1] == '\n')
620 return; /* end of header */
621 continue;
623 if (split_ident_line(&ident,
624 ident_line, line_end - ident_line) ||
625 !ident.date_begin || !ident.date_end)
626 goto fail_exit; /* malformed "author" line */
627 break;
630 date = strtoul(ident.date_begin, &date_end, 10);
631 if (date_end != ident.date_end)
632 goto fail_exit; /* malformed date */
633 *(author_date_slab_at(author_date, commit)) = date;
635 fail_exit:
636 unuse_commit_buffer(commit, buffer);
639 static int compare_commits_by_author_date(const void *a_, const void *b_,
640 void *cb_data)
642 const struct commit *a = a_, *b = b_;
643 struct author_date_slab *author_date = cb_data;
644 unsigned long a_date = *(author_date_slab_at(author_date, a));
645 unsigned long b_date = *(author_date_slab_at(author_date, b));
647 /* newer commits with larger date first */
648 if (a_date < b_date)
649 return 1;
650 else if (a_date > b_date)
651 return -1;
652 return 0;
655 int compare_commits_by_commit_date(const void *a_, const void *b_, void *unused)
657 const struct commit *a = a_, *b = b_;
658 /* newer commits with larger date first */
659 if (a->date < b->date)
660 return 1;
661 else if (a->date > b->date)
662 return -1;
663 return 0;
667 * Performs an in-place topological sort on the list supplied.
669 void sort_in_topological_order(struct commit_list **list, enum rev_sort_order sort_order)
671 struct commit_list *next, *orig = *list;
672 struct commit_list **pptr;
673 struct indegree_slab indegree;
674 struct prio_queue queue;
675 struct commit *commit;
676 struct author_date_slab author_date;
678 if (!orig)
679 return;
680 *list = NULL;
682 init_indegree_slab(&indegree);
683 memset(&queue, '\0', sizeof(queue));
685 switch (sort_order) {
686 default: /* REV_SORT_IN_GRAPH_ORDER */
687 queue.compare = NULL;
688 break;
689 case REV_SORT_BY_COMMIT_DATE:
690 queue.compare = compare_commits_by_commit_date;
691 break;
692 case REV_SORT_BY_AUTHOR_DATE:
693 init_author_date_slab(&author_date);
694 queue.compare = compare_commits_by_author_date;
695 queue.cb_data = &author_date;
696 break;
699 /* Mark them and clear the indegree */
700 for (next = orig; next; next = next->next) {
701 struct commit *commit = next->item;
702 *(indegree_slab_at(&indegree, commit)) = 1;
703 /* also record the author dates, if needed */
704 if (sort_order == REV_SORT_BY_AUTHOR_DATE)
705 record_author_date(&author_date, commit);
708 /* update the indegree */
709 for (next = orig; next; next = next->next) {
710 struct commit_list *parents = next->item->parents;
711 while (parents) {
712 struct commit *parent = parents->item;
713 int *pi = indegree_slab_at(&indegree, parent);
715 if (*pi)
716 (*pi)++;
717 parents = parents->next;
722 * find the tips
724 * tips are nodes not reachable from any other node in the list
726 * the tips serve as a starting set for the work queue.
728 for (next = orig; next; next = next->next) {
729 struct commit *commit = next->item;
731 if (*(indegree_slab_at(&indegree, commit)) == 1)
732 prio_queue_put(&queue, commit);
736 * This is unfortunate; the initial tips need to be shown
737 * in the order given from the revision traversal machinery.
739 if (sort_order == REV_SORT_IN_GRAPH_ORDER)
740 prio_queue_reverse(&queue);
742 /* We no longer need the commit list */
743 free_commit_list(orig);
745 pptr = list;
746 *list = NULL;
747 while ((commit = prio_queue_get(&queue)) != NULL) {
748 struct commit_list *parents;
750 for (parents = commit->parents; parents ; parents = parents->next) {
751 struct commit *parent = parents->item;
752 int *pi = indegree_slab_at(&indegree, parent);
754 if (!*pi)
755 continue;
758 * parents are only enqueued for emission
759 * when all their children have been emitted thereby
760 * guaranteeing topological order.
762 if (--(*pi) == 1)
763 prio_queue_put(&queue, parent);
766 * all children of commit have already been
767 * emitted. we can emit it now.
769 *(indegree_slab_at(&indegree, commit)) = 0;
771 pptr = &commit_list_insert(commit, pptr)->next;
774 clear_indegree_slab(&indegree);
775 clear_prio_queue(&queue);
776 if (sort_order == REV_SORT_BY_AUTHOR_DATE)
777 clear_author_date_slab(&author_date);
780 /* merge-base stuff */
782 /* Remember to update object flag allocation in object.h */
783 #define PARENT1 (1u<<16)
784 #define PARENT2 (1u<<17)
785 #define STALE (1u<<18)
786 #define RESULT (1u<<19)
788 static const unsigned all_flags = (PARENT1 | PARENT2 | STALE | RESULT);
790 static struct commit *interesting(struct commit_list *list)
792 while (list) {
793 struct commit *commit = list->item;
794 list = list->next;
795 if (commit->object.flags & STALE)
796 continue;
797 return commit;
799 return NULL;
802 /* all input commits in one and twos[] must have been parsed! */
803 static struct commit_list *paint_down_to_common(struct commit *one, int n, struct commit **twos)
805 struct commit_list *list = NULL;
806 struct commit_list *result = NULL;
807 int i;
809 one->object.flags |= PARENT1;
810 commit_list_insert_by_date(one, &list);
811 if (!n)
812 return list;
813 for (i = 0; i < n; i++) {
814 twos[i]->object.flags |= PARENT2;
815 commit_list_insert_by_date(twos[i], &list);
818 while (interesting(list)) {
819 struct commit *commit;
820 struct commit_list *parents;
821 struct commit_list *next;
822 int flags;
824 commit = list->item;
825 next = list->next;
826 free(list);
827 list = next;
829 flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
830 if (flags == (PARENT1 | PARENT2)) {
831 if (!(commit->object.flags & RESULT)) {
832 commit->object.flags |= RESULT;
833 commit_list_insert_by_date(commit, &result);
835 /* Mark parents of a found merge stale */
836 flags |= STALE;
838 parents = commit->parents;
839 while (parents) {
840 struct commit *p = parents->item;
841 parents = parents->next;
842 if ((p->object.flags & flags) == flags)
843 continue;
844 if (parse_commit(p))
845 return NULL;
846 p->object.flags |= flags;
847 commit_list_insert_by_date(p, &list);
851 free_commit_list(list);
852 return result;
855 static struct commit_list *merge_bases_many(struct commit *one, int n, struct commit **twos)
857 struct commit_list *list = NULL;
858 struct commit_list *result = NULL;
859 int i;
861 for (i = 0; i < n; i++) {
862 if (one == twos[i])
864 * We do not mark this even with RESULT so we do not
865 * have to clean it up.
867 return commit_list_insert(one, &result);
870 if (parse_commit(one))
871 return NULL;
872 for (i = 0; i < n; i++) {
873 if (parse_commit(twos[i]))
874 return NULL;
877 list = paint_down_to_common(one, n, twos);
879 while (list) {
880 struct commit_list *next = list->next;
881 if (!(list->item->object.flags & STALE))
882 commit_list_insert_by_date(list->item, &result);
883 free(list);
884 list = next;
886 return result;
889 struct commit_list *get_octopus_merge_bases(struct commit_list *in)
891 struct commit_list *i, *j, *k, *ret = NULL;
893 if (!in)
894 return ret;
896 commit_list_insert(in->item, &ret);
898 for (i = in->next; i; i = i->next) {
899 struct commit_list *new = NULL, *end = NULL;
901 for (j = ret; j; j = j->next) {
902 struct commit_list *bases;
903 bases = get_merge_bases(i->item, j->item, 1);
904 if (!new)
905 new = bases;
906 else
907 end->next = bases;
908 for (k = bases; k; k = k->next)
909 end = k;
911 ret = new;
913 return ret;
916 static int remove_redundant(struct commit **array, int cnt)
919 * Some commit in the array may be an ancestor of
920 * another commit. Move such commit to the end of
921 * the array, and return the number of commits that
922 * are independent from each other.
924 struct commit **work;
925 unsigned char *redundant;
926 int *filled_index;
927 int i, j, filled;
929 work = xcalloc(cnt, sizeof(*work));
930 redundant = xcalloc(cnt, 1);
931 filled_index = xmalloc(sizeof(*filled_index) * (cnt - 1));
933 for (i = 0; i < cnt; i++)
934 parse_commit(array[i]);
935 for (i = 0; i < cnt; i++) {
936 struct commit_list *common;
938 if (redundant[i])
939 continue;
940 for (j = filled = 0; j < cnt; j++) {
941 if (i == j || redundant[j])
942 continue;
943 filled_index[filled] = j;
944 work[filled++] = array[j];
946 common = paint_down_to_common(array[i], filled, work);
947 if (array[i]->object.flags & PARENT2)
948 redundant[i] = 1;
949 for (j = 0; j < filled; j++)
950 if (work[j]->object.flags & PARENT1)
951 redundant[filled_index[j]] = 1;
952 clear_commit_marks(array[i], all_flags);
953 for (j = 0; j < filled; j++)
954 clear_commit_marks(work[j], all_flags);
955 free_commit_list(common);
958 /* Now collect the result */
959 memcpy(work, array, sizeof(*array) * cnt);
960 for (i = filled = 0; i < cnt; i++)
961 if (!redundant[i])
962 array[filled++] = work[i];
963 for (j = filled, i = 0; i < cnt; i++)
964 if (redundant[i])
965 array[j++] = work[i];
966 free(work);
967 free(redundant);
968 free(filled_index);
969 return filled;
972 struct commit_list *get_merge_bases_many(struct commit *one,
973 int n,
974 struct commit **twos,
975 int cleanup)
977 struct commit_list *list;
978 struct commit **rslt;
979 struct commit_list *result;
980 int cnt, i;
982 result = merge_bases_many(one, n, twos);
983 for (i = 0; i < n; i++) {
984 if (one == twos[i])
985 return result;
987 if (!result || !result->next) {
988 if (cleanup) {
989 clear_commit_marks(one, all_flags);
990 clear_commit_marks_many(n, twos, all_flags);
992 return result;
995 /* There are more than one */
996 cnt = 0;
997 list = result;
998 while (list) {
999 list = list->next;
1000 cnt++;
1002 rslt = xcalloc(cnt, sizeof(*rslt));
1003 for (list = result, i = 0; list; list = list->next)
1004 rslt[i++] = list->item;
1005 free_commit_list(result);
1007 clear_commit_marks(one, all_flags);
1008 clear_commit_marks_many(n, twos, all_flags);
1010 cnt = remove_redundant(rslt, cnt);
1011 result = NULL;
1012 for (i = 0; i < cnt; i++)
1013 commit_list_insert_by_date(rslt[i], &result);
1014 free(rslt);
1015 return result;
1018 struct commit_list *get_merge_bases(struct commit *one, struct commit *two,
1019 int cleanup)
1021 return get_merge_bases_many(one, 1, &two, cleanup);
1025 * Is "commit" a descendant of one of the elements on the "with_commit" list?
1027 int is_descendant_of(struct commit *commit, struct commit_list *with_commit)
1029 if (!with_commit)
1030 return 1;
1031 while (with_commit) {
1032 struct commit *other;
1034 other = with_commit->item;
1035 with_commit = with_commit->next;
1036 if (in_merge_bases(other, commit))
1037 return 1;
1039 return 0;
1043 * Is "commit" an ancestor of one of the "references"?
1045 int in_merge_bases_many(struct commit *commit, int nr_reference, struct commit **reference)
1047 struct commit_list *bases;
1048 int ret = 0, i;
1050 if (parse_commit(commit))
1051 return ret;
1052 for (i = 0; i < nr_reference; i++)
1053 if (parse_commit(reference[i]))
1054 return ret;
1056 bases = paint_down_to_common(commit, nr_reference, reference);
1057 if (commit->object.flags & PARENT2)
1058 ret = 1;
1059 clear_commit_marks(commit, all_flags);
1060 clear_commit_marks_many(nr_reference, reference, all_flags);
1061 free_commit_list(bases);
1062 return ret;
1066 * Is "commit" an ancestor of (i.e. reachable from) the "reference"?
1068 int in_merge_bases(struct commit *commit, struct commit *reference)
1070 return in_merge_bases_many(commit, 1, &reference);
1073 struct commit_list *reduce_heads(struct commit_list *heads)
1075 struct commit_list *p;
1076 struct commit_list *result = NULL, **tail = &result;
1077 struct commit **array;
1078 int num_head, i;
1080 if (!heads)
1081 return NULL;
1083 /* Uniquify */
1084 for (p = heads; p; p = p->next)
1085 p->item->object.flags &= ~STALE;
1086 for (p = heads, num_head = 0; p; p = p->next) {
1087 if (p->item->object.flags & STALE)
1088 continue;
1089 p->item->object.flags |= STALE;
1090 num_head++;
1092 array = xcalloc(num_head, sizeof(*array));
1093 for (p = heads, i = 0; p; p = p->next) {
1094 if (p->item->object.flags & STALE) {
1095 array[i++] = p->item;
1096 p->item->object.flags &= ~STALE;
1099 num_head = remove_redundant(array, num_head);
1100 for (i = 0; i < num_head; i++)
1101 tail = &commit_list_insert(array[i], tail)->next;
1102 return result;
1105 static const char gpg_sig_header[] = "gpgsig";
1106 static const int gpg_sig_header_len = sizeof(gpg_sig_header) - 1;
1108 static int do_sign_commit(struct strbuf *buf, const char *keyid)
1110 struct strbuf sig = STRBUF_INIT;
1111 int inspos, copypos;
1113 /* find the end of the header */
1114 inspos = strstr(buf->buf, "\n\n") - buf->buf + 1;
1116 if (!keyid || !*keyid)
1117 keyid = get_signing_key();
1118 if (sign_buffer(buf, &sig, keyid)) {
1119 strbuf_release(&sig);
1120 return -1;
1123 for (copypos = 0; sig.buf[copypos]; ) {
1124 const char *bol = sig.buf + copypos;
1125 const char *eol = strchrnul(bol, '\n');
1126 int len = (eol - bol) + !!*eol;
1128 if (!copypos) {
1129 strbuf_insert(buf, inspos, gpg_sig_header, gpg_sig_header_len);
1130 inspos += gpg_sig_header_len;
1132 strbuf_insert(buf, inspos++, " ", 1);
1133 strbuf_insert(buf, inspos, bol, len);
1134 inspos += len;
1135 copypos += len;
1137 strbuf_release(&sig);
1138 return 0;
1141 int parse_signed_commit(const struct commit *commit,
1142 struct strbuf *payload, struct strbuf *signature)
1145 unsigned long size;
1146 const char *buffer = get_commit_buffer(commit, &size);
1147 int in_signature, saw_signature = -1;
1148 const char *line, *tail;
1150 line = buffer;
1151 tail = buffer + size;
1152 in_signature = 0;
1153 saw_signature = 0;
1154 while (line < tail) {
1155 const char *sig = NULL;
1156 const char *next = memchr(line, '\n', tail - line);
1158 next = next ? next + 1 : tail;
1159 if (in_signature && line[0] == ' ')
1160 sig = line + 1;
1161 else if (starts_with(line, gpg_sig_header) &&
1162 line[gpg_sig_header_len] == ' ')
1163 sig = line + gpg_sig_header_len + 1;
1164 if (sig) {
1165 strbuf_add(signature, sig, next - sig);
1166 saw_signature = 1;
1167 in_signature = 1;
1168 } else {
1169 if (*line == '\n')
1170 /* dump the whole remainder of the buffer */
1171 next = tail;
1172 strbuf_add(payload, line, next - line);
1173 in_signature = 0;
1175 line = next;
1177 unuse_commit_buffer(commit, buffer);
1178 return saw_signature;
1181 static void handle_signed_tag(struct commit *parent, struct commit_extra_header ***tail)
1183 struct merge_remote_desc *desc;
1184 struct commit_extra_header *mergetag;
1185 char *buf;
1186 unsigned long size, len;
1187 enum object_type type;
1189 desc = merge_remote_util(parent);
1190 if (!desc || !desc->obj)
1191 return;
1192 buf = read_sha1_file(desc->obj->sha1, &type, &size);
1193 if (!buf || type != OBJ_TAG)
1194 goto free_return;
1195 len = parse_signature(buf, size);
1196 if (size == len)
1197 goto free_return;
1199 * We could verify this signature and either omit the tag when
1200 * it does not validate, but the integrator may not have the
1201 * public key of the signer of the tag he is merging, while a
1202 * later auditor may have it while auditing, so let's not run
1203 * verify-signed-buffer here for now...
1205 * if (verify_signed_buffer(buf, len, buf + len, size - len, ...))
1206 * warn("warning: signed tag unverified.");
1208 mergetag = xcalloc(1, sizeof(*mergetag));
1209 mergetag->key = xstrdup("mergetag");
1210 mergetag->value = buf;
1211 mergetag->len = size;
1213 **tail = mergetag;
1214 *tail = &mergetag->next;
1215 return;
1217 free_return:
1218 free(buf);
1221 static struct {
1222 char result;
1223 const char *check;
1224 } sigcheck_gpg_status[] = {
1225 { 'G', "\n[GNUPG:] GOODSIG " },
1226 { 'B', "\n[GNUPG:] BADSIG " },
1227 { 'U', "\n[GNUPG:] TRUST_NEVER" },
1228 { 'U', "\n[GNUPG:] TRUST_UNDEFINED" },
1231 static void parse_gpg_output(struct signature_check *sigc)
1233 const char *buf = sigc->gpg_status;
1234 int i;
1236 /* Iterate over all search strings */
1237 for (i = 0; i < ARRAY_SIZE(sigcheck_gpg_status); i++) {
1238 const char *found, *next;
1240 found = skip_prefix(buf, sigcheck_gpg_status[i].check + 1);
1241 if (!found) {
1242 found = strstr(buf, sigcheck_gpg_status[i].check);
1243 if (!found)
1244 continue;
1245 found += strlen(sigcheck_gpg_status[i].check);
1247 sigc->result = sigcheck_gpg_status[i].result;
1248 /* The trust messages are not followed by key/signer information */
1249 if (sigc->result != 'U') {
1250 sigc->key = xmemdupz(found, 16);
1251 found += 17;
1252 next = strchrnul(found, '\n');
1253 sigc->signer = xmemdupz(found, next - found);
1258 void check_commit_signature(const struct commit* commit, struct signature_check *sigc)
1260 struct strbuf payload = STRBUF_INIT;
1261 struct strbuf signature = STRBUF_INIT;
1262 struct strbuf gpg_output = STRBUF_INIT;
1263 struct strbuf gpg_status = STRBUF_INIT;
1264 int status;
1266 sigc->result = 'N';
1268 if (parse_signed_commit(commit, &payload, &signature) <= 0)
1269 goto out;
1270 status = verify_signed_buffer(payload.buf, payload.len,
1271 signature.buf, signature.len,
1272 &gpg_output, &gpg_status);
1273 if (status && !gpg_output.len)
1274 goto out;
1275 sigc->gpg_output = strbuf_detach(&gpg_output, NULL);
1276 sigc->gpg_status = strbuf_detach(&gpg_status, NULL);
1277 parse_gpg_output(sigc);
1279 out:
1280 strbuf_release(&gpg_status);
1281 strbuf_release(&gpg_output);
1282 strbuf_release(&payload);
1283 strbuf_release(&signature);
1288 void append_merge_tag_headers(struct commit_list *parents,
1289 struct commit_extra_header ***tail)
1291 while (parents) {
1292 struct commit *parent = parents->item;
1293 handle_signed_tag(parent, tail);
1294 parents = parents->next;
1298 static void add_extra_header(struct strbuf *buffer,
1299 struct commit_extra_header *extra)
1301 strbuf_addstr(buffer, extra->key);
1302 if (extra->len)
1303 strbuf_add_lines(buffer, " ", extra->value, extra->len);
1304 else
1305 strbuf_addch(buffer, '\n');
1308 struct commit_extra_header *read_commit_extra_headers(struct commit *commit,
1309 const char **exclude)
1311 struct commit_extra_header *extra = NULL;
1312 unsigned long size;
1313 const char *buffer = get_commit_buffer(commit, &size);
1314 extra = read_commit_extra_header_lines(buffer, size, exclude);
1315 unuse_commit_buffer(commit, buffer);
1316 return extra;
1319 static inline int standard_header_field(const char *field, size_t len)
1321 return ((len == 4 && !memcmp(field, "tree ", 5)) ||
1322 (len == 6 && !memcmp(field, "parent ", 7)) ||
1323 (len == 6 && !memcmp(field, "author ", 7)) ||
1324 (len == 9 && !memcmp(field, "committer ", 10)) ||
1325 (len == 8 && !memcmp(field, "encoding ", 9)));
1328 static int excluded_header_field(const char *field, size_t len, const char **exclude)
1330 if (!exclude)
1331 return 0;
1333 while (*exclude) {
1334 size_t xlen = strlen(*exclude);
1335 if (len == xlen &&
1336 !memcmp(field, *exclude, xlen) && field[xlen] == ' ')
1337 return 1;
1338 exclude++;
1340 return 0;
1343 static struct commit_extra_header *read_commit_extra_header_lines(
1344 const char *buffer, size_t size,
1345 const char **exclude)
1347 struct commit_extra_header *extra = NULL, **tail = &extra, *it = NULL;
1348 const char *line, *next, *eof, *eob;
1349 struct strbuf buf = STRBUF_INIT;
1351 for (line = buffer, eob = line + size;
1352 line < eob && *line != '\n';
1353 line = next) {
1354 next = memchr(line, '\n', eob - line);
1355 next = next ? next + 1 : eob;
1356 if (*line == ' ') {
1357 /* continuation */
1358 if (it)
1359 strbuf_add(&buf, line + 1, next - (line + 1));
1360 continue;
1362 if (it)
1363 it->value = strbuf_detach(&buf, &it->len);
1364 strbuf_reset(&buf);
1365 it = NULL;
1367 eof = strchr(line, ' ');
1368 if (next <= eof)
1369 eof = next;
1371 if (standard_header_field(line, eof - line) ||
1372 excluded_header_field(line, eof - line, exclude))
1373 continue;
1375 it = xcalloc(1, sizeof(*it));
1376 it->key = xmemdupz(line, eof-line);
1377 *tail = it;
1378 tail = &it->next;
1379 if (eof + 1 < next)
1380 strbuf_add(&buf, eof + 1, next - (eof + 1));
1382 if (it)
1383 it->value = strbuf_detach(&buf, &it->len);
1384 return extra;
1387 void free_commit_extra_headers(struct commit_extra_header *extra)
1389 while (extra) {
1390 struct commit_extra_header *next = extra->next;
1391 free(extra->key);
1392 free(extra->value);
1393 free(extra);
1394 extra = next;
1398 int commit_tree(const char *msg, size_t msg_len,
1399 const unsigned char *tree,
1400 struct commit_list *parents, unsigned char *ret,
1401 const char *author, const char *sign_commit)
1403 struct commit_extra_header *extra = NULL, **tail = &extra;
1404 int result;
1406 append_merge_tag_headers(parents, &tail);
1407 result = commit_tree_extended(msg, msg_len, tree, parents, ret,
1408 author, sign_commit, extra);
1409 free_commit_extra_headers(extra);
1410 return result;
1413 static int find_invalid_utf8(const char *buf, int len)
1415 int offset = 0;
1416 static const unsigned int max_codepoint[] = {
1417 0x7f, 0x7ff, 0xffff, 0x10ffff
1420 while (len) {
1421 unsigned char c = *buf++;
1422 int bytes, bad_offset;
1423 unsigned int codepoint;
1424 unsigned int min_val, max_val;
1426 len--;
1427 offset++;
1429 /* Simple US-ASCII? No worries. */
1430 if (c < 0x80)
1431 continue;
1433 bad_offset = offset-1;
1436 * Count how many more high bits set: that's how
1437 * many more bytes this sequence should have.
1439 bytes = 0;
1440 while (c & 0x40) {
1441 c <<= 1;
1442 bytes++;
1446 * Must be between 1 and 3 more bytes. Longer sequences result in
1447 * codepoints beyond U+10FFFF, which are guaranteed never to exist.
1449 if (bytes < 1 || 3 < bytes)
1450 return bad_offset;
1452 /* Do we *have* that many bytes? */
1453 if (len < bytes)
1454 return bad_offset;
1457 * Place the encoded bits at the bottom of the value and compute the
1458 * valid range.
1460 codepoint = (c & 0x7f) >> bytes;
1461 min_val = max_codepoint[bytes-1] + 1;
1462 max_val = max_codepoint[bytes];
1464 offset += bytes;
1465 len -= bytes;
1467 /* And verify that they are good continuation bytes */
1468 do {
1469 codepoint <<= 6;
1470 codepoint |= *buf & 0x3f;
1471 if ((*buf++ & 0xc0) != 0x80)
1472 return bad_offset;
1473 } while (--bytes);
1475 /* Reject codepoints that are out of range for the sequence length. */
1476 if (codepoint < min_val || codepoint > max_val)
1477 return bad_offset;
1478 /* Surrogates are only for UTF-16 and cannot be encoded in UTF-8. */
1479 if ((codepoint & 0x1ff800) == 0xd800)
1480 return bad_offset;
1481 /* U+xxFFFE and U+xxFFFF are guaranteed non-characters. */
1482 if ((codepoint & 0xfffe) == 0xfffe)
1483 return bad_offset;
1484 /* So are anything in the range U+FDD0..U+FDEF. */
1485 if (codepoint >= 0xfdd0 && codepoint <= 0xfdef)
1486 return bad_offset;
1488 return -1;
1492 * This verifies that the buffer is in proper utf8 format.
1494 * If it isn't, it assumes any non-utf8 characters are Latin1,
1495 * and does the conversion.
1497 static int verify_utf8(struct strbuf *buf)
1499 int ok = 1;
1500 long pos = 0;
1502 for (;;) {
1503 int bad;
1504 unsigned char c;
1505 unsigned char replace[2];
1507 bad = find_invalid_utf8(buf->buf + pos, buf->len - pos);
1508 if (bad < 0)
1509 return ok;
1510 pos += bad;
1511 ok = 0;
1512 c = buf->buf[pos];
1513 strbuf_remove(buf, pos, 1);
1515 /* We know 'c' must be in the range 128-255 */
1516 replace[0] = 0xc0 + (c >> 6);
1517 replace[1] = 0x80 + (c & 0x3f);
1518 strbuf_insert(buf, pos, replace, 2);
1519 pos += 2;
1523 static const char commit_utf8_warn[] =
1524 "Warning: commit message did not conform to UTF-8.\n"
1525 "You may want to amend it after fixing the message, or set the config\n"
1526 "variable i18n.commitencoding to the encoding your project uses.\n";
1528 int commit_tree_extended(const char *msg, size_t msg_len,
1529 const unsigned char *tree,
1530 struct commit_list *parents, unsigned char *ret,
1531 const char *author, const char *sign_commit,
1532 struct commit_extra_header *extra)
1534 int result;
1535 int encoding_is_utf8;
1536 struct strbuf buffer;
1538 assert_sha1_type(tree, OBJ_TREE);
1540 if (memchr(msg, '\0', msg_len))
1541 return error("a NUL byte in commit log message not allowed.");
1543 /* Not having i18n.commitencoding is the same as having utf-8 */
1544 encoding_is_utf8 = is_encoding_utf8(git_commit_encoding);
1546 strbuf_init(&buffer, 8192); /* should avoid reallocs for the headers */
1547 strbuf_addf(&buffer, "tree %s\n", sha1_to_hex(tree));
1550 * NOTE! This ordering means that the same exact tree merged with a
1551 * different order of parents will be a _different_ changeset even
1552 * if everything else stays the same.
1554 while (parents) {
1555 struct commit_list *next = parents->next;
1556 struct commit *parent = parents->item;
1558 strbuf_addf(&buffer, "parent %s\n",
1559 sha1_to_hex(parent->object.sha1));
1560 free(parents);
1561 parents = next;
1564 /* Person/date information */
1565 if (!author)
1566 author = git_author_info(IDENT_STRICT);
1567 strbuf_addf(&buffer, "author %s\n", author);
1568 strbuf_addf(&buffer, "committer %s\n", git_committer_info(IDENT_STRICT));
1569 if (!encoding_is_utf8)
1570 strbuf_addf(&buffer, "encoding %s\n", git_commit_encoding);
1572 while (extra) {
1573 add_extra_header(&buffer, extra);
1574 extra = extra->next;
1576 strbuf_addch(&buffer, '\n');
1578 /* And add the comment */
1579 strbuf_add(&buffer, msg, msg_len);
1581 /* And check the encoding */
1582 if (encoding_is_utf8 && !verify_utf8(&buffer))
1583 fprintf(stderr, commit_utf8_warn);
1585 if (sign_commit && do_sign_commit(&buffer, sign_commit))
1586 return -1;
1588 result = write_sha1_file(buffer.buf, buffer.len, commit_type, ret);
1589 strbuf_release(&buffer);
1590 return result;
1593 struct commit *get_merge_parent(const char *name)
1595 struct object *obj;
1596 struct commit *commit;
1597 unsigned char sha1[20];
1598 if (get_sha1(name, sha1))
1599 return NULL;
1600 obj = parse_object(sha1);
1601 commit = (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
1602 if (commit && !commit->util) {
1603 struct merge_remote_desc *desc;
1604 desc = xmalloc(sizeof(*desc));
1605 desc->obj = obj;
1606 desc->name = strdup(name);
1607 commit->util = desc;
1609 return commit;
1613 * Append a commit to the end of the commit_list.
1615 * next starts by pointing to the variable that holds the head of an
1616 * empty commit_list, and is updated to point to the "next" field of
1617 * the last item on the list as new commits are appended.
1619 * Usage example:
1621 * struct commit_list *list;
1622 * struct commit_list **next = &list;
1624 * next = commit_list_append(c1, next);
1625 * next = commit_list_append(c2, next);
1626 * assert(commit_list_count(list) == 2);
1627 * return list;
1629 struct commit_list **commit_list_append(struct commit *commit,
1630 struct commit_list **next)
1632 struct commit_list *new = xmalloc(sizeof(struct commit_list));
1633 new->item = commit;
1634 *next = new;
1635 new->next = NULL;
1636 return &new->next;
1639 void print_commit_list(struct commit_list *list,
1640 const char *format_cur,
1641 const char *format_last)
1643 for ( ; list; list = list->next) {
1644 const char *format = list->next ? format_cur : format_last;
1645 printf(format, sha1_to_hex(list->item->object.sha1));