Merge branch 'jk/tag-sort'
[git.git] / commit.c
blobdce3d69dfdf5843b6dbae78a5c85a4060ca7604b
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 struct commit *lookup_commit_reference_gently(const unsigned char *sha1,
22 int quiet)
24 struct object *obj = deref_tag(parse_object(sha1), NULL, 0);
26 if (!obj)
27 return NULL;
28 return object_as_type(obj, OBJ_COMMIT, quiet);
31 struct commit *lookup_commit_reference(const unsigned char *sha1)
33 return lookup_commit_reference_gently(sha1, 0);
36 struct commit *lookup_commit_or_die(const unsigned char *sha1, const char *ref_name)
38 struct commit *c = lookup_commit_reference(sha1);
39 if (!c)
40 die(_("could not parse %s"), ref_name);
41 if (hashcmp(sha1, c->object.sha1)) {
42 warning(_("%s %s is not a commit!"),
43 ref_name, sha1_to_hex(sha1));
45 return c;
48 struct commit *lookup_commit(const unsigned char *sha1)
50 struct object *obj = lookup_object(sha1);
51 if (!obj)
52 return create_object(sha1, alloc_commit_node());
53 return object_as_type(obj, OBJ_COMMIT, 0);
56 struct commit *lookup_commit_reference_by_name(const char *name)
58 unsigned char sha1[20];
59 struct commit *commit;
61 if (get_sha1_committish(name, sha1))
62 return NULL;
63 commit = lookup_commit_reference(sha1);
64 if (parse_commit(commit))
65 return NULL;
66 return commit;
69 static unsigned long parse_commit_date(const char *buf, const char *tail)
71 const char *dateptr;
73 if (buf + 6 >= tail)
74 return 0;
75 if (memcmp(buf, "author", 6))
76 return 0;
77 while (buf < tail && *buf++ != '\n')
78 /* nada */;
79 if (buf + 9 >= tail)
80 return 0;
81 if (memcmp(buf, "committer", 9))
82 return 0;
83 while (buf < tail && *buf++ != '>')
84 /* nada */;
85 if (buf >= tail)
86 return 0;
87 dateptr = buf;
88 while (buf < tail && *buf++ != '\n')
89 /* nada */;
90 if (buf >= tail)
91 return 0;
92 /* dateptr < buf && buf[-1] == '\n', so strtoul will stop at buf-1 */
93 return strtoul(dateptr, NULL, 10);
96 static struct commit_graft **commit_graft;
97 static int commit_graft_alloc, commit_graft_nr;
99 static const unsigned char *commit_graft_sha1_access(size_t index, void *table)
101 struct commit_graft **commit_graft_table = table;
102 return commit_graft_table[index]->sha1;
105 static int commit_graft_pos(const unsigned char *sha1)
107 return sha1_pos(sha1, commit_graft, commit_graft_nr,
108 commit_graft_sha1_access);
111 int register_commit_graft(struct commit_graft *graft, int ignore_dups)
113 int pos = commit_graft_pos(graft->sha1);
115 if (0 <= pos) {
116 if (ignore_dups)
117 free(graft);
118 else {
119 free(commit_graft[pos]);
120 commit_graft[pos] = graft;
122 return 1;
124 pos = -pos - 1;
125 ALLOC_GROW(commit_graft, commit_graft_nr + 1, commit_graft_alloc);
126 commit_graft_nr++;
127 if (pos < commit_graft_nr)
128 memmove(commit_graft + pos + 1,
129 commit_graft + pos,
130 (commit_graft_nr - pos - 1) *
131 sizeof(*commit_graft));
132 commit_graft[pos] = graft;
133 return 0;
136 struct commit_graft *read_graft_line(char *buf, int len)
138 /* The format is just "Commit Parent1 Parent2 ...\n" */
139 int i;
140 struct commit_graft *graft = NULL;
142 while (len && isspace(buf[len-1]))
143 buf[--len] = '\0';
144 if (buf[0] == '#' || buf[0] == '\0')
145 return NULL;
146 if ((len + 1) % 41)
147 goto bad_graft_data;
148 i = (len + 1) / 41 - 1;
149 graft = xmalloc(sizeof(*graft) + 20 * i);
150 graft->nr_parent = i;
151 if (get_sha1_hex(buf, graft->sha1))
152 goto bad_graft_data;
153 for (i = 40; i < len; i += 41) {
154 if (buf[i] != ' ')
155 goto bad_graft_data;
156 if (get_sha1_hex(buf + i + 1, graft->parent[i/41]))
157 goto bad_graft_data;
159 return graft;
161 bad_graft_data:
162 error("bad graft data: %s", buf);
163 free(graft);
164 return NULL;
167 static int read_graft_file(const char *graft_file)
169 FILE *fp = fopen(graft_file, "r");
170 struct strbuf buf = STRBUF_INIT;
171 if (!fp)
172 return -1;
173 while (!strbuf_getwholeline(&buf, fp, '\n')) {
174 /* The format is just "Commit Parent1 Parent2 ...\n" */
175 struct commit_graft *graft = read_graft_line(buf.buf, buf.len);
176 if (!graft)
177 continue;
178 if (register_commit_graft(graft, 1))
179 error("duplicate graft data: %s", buf.buf);
181 fclose(fp);
182 strbuf_release(&buf);
183 return 0;
186 static void prepare_commit_graft(void)
188 static int commit_graft_prepared;
189 char *graft_file;
191 if (commit_graft_prepared)
192 return;
193 graft_file = get_graft_file();
194 read_graft_file(graft_file);
195 /* make sure shallows are read */
196 is_repository_shallow();
197 commit_graft_prepared = 1;
200 struct commit_graft *lookup_commit_graft(const unsigned char *sha1)
202 int pos;
203 prepare_commit_graft();
204 pos = commit_graft_pos(sha1);
205 if (pos < 0)
206 return NULL;
207 return commit_graft[pos];
210 int for_each_commit_graft(each_commit_graft_fn fn, void *cb_data)
212 int i, ret;
213 for (i = ret = 0; i < commit_graft_nr && !ret; i++)
214 ret = fn(commit_graft[i], cb_data);
215 return ret;
218 int unregister_shallow(const unsigned char *sha1)
220 int pos = commit_graft_pos(sha1);
221 if (pos < 0)
222 return -1;
223 if (pos + 1 < commit_graft_nr)
224 memmove(commit_graft + pos, commit_graft + pos + 1,
225 sizeof(struct commit_graft *)
226 * (commit_graft_nr - pos - 1));
227 commit_graft_nr--;
228 return 0;
231 struct commit_buffer {
232 void *buffer;
233 unsigned long size;
235 define_commit_slab(buffer_slab, struct commit_buffer);
236 static struct buffer_slab buffer_slab = COMMIT_SLAB_INIT(1, buffer_slab);
238 void set_commit_buffer(struct commit *commit, void *buffer, unsigned long size)
240 struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
241 v->buffer = buffer;
242 v->size = size;
245 const void *get_cached_commit_buffer(const struct commit *commit, unsigned long *sizep)
247 struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
248 if (sizep)
249 *sizep = v->size;
250 return v->buffer;
253 const void *get_commit_buffer(const struct commit *commit, unsigned long *sizep)
255 const void *ret = get_cached_commit_buffer(commit, sizep);
256 if (!ret) {
257 enum object_type type;
258 unsigned long size;
259 ret = read_sha1_file(commit->object.sha1, &type, &size);
260 if (!ret)
261 die("cannot read commit object %s",
262 sha1_to_hex(commit->object.sha1));
263 if (type != OBJ_COMMIT)
264 die("expected commit for %s, got %s",
265 sha1_to_hex(commit->object.sha1), typename(type));
266 if (sizep)
267 *sizep = size;
269 return ret;
272 void unuse_commit_buffer(const struct commit *commit, const void *buffer)
274 struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
275 if (v->buffer != buffer)
276 free((void *)buffer);
279 void free_commit_buffer(struct commit *commit)
281 struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
282 free(v->buffer);
283 v->buffer = NULL;
284 v->size = 0;
287 const void *detach_commit_buffer(struct commit *commit, unsigned long *sizep)
289 struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
290 void *ret;
292 ret = v->buffer;
293 if (sizep)
294 *sizep = v->size;
296 v->buffer = NULL;
297 v->size = 0;
298 return ret;
301 int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long size)
303 const char *tail = buffer;
304 const char *bufptr = buffer;
305 unsigned char parent[20];
306 struct commit_list **pptr;
307 struct commit_graft *graft;
309 if (item->object.parsed)
310 return 0;
311 item->object.parsed = 1;
312 tail += size;
313 if (tail <= bufptr + 46 || memcmp(bufptr, "tree ", 5) || bufptr[45] != '\n')
314 return error("bogus commit object %s", sha1_to_hex(item->object.sha1));
315 if (get_sha1_hex(bufptr + 5, parent) < 0)
316 return error("bad tree pointer in commit %s",
317 sha1_to_hex(item->object.sha1));
318 item->tree = lookup_tree(parent);
319 bufptr += 46; /* "tree " + "hex sha1" + "\n" */
320 pptr = &item->parents;
322 graft = lookup_commit_graft(item->object.sha1);
323 while (bufptr + 48 < tail && !memcmp(bufptr, "parent ", 7)) {
324 struct commit *new_parent;
326 if (tail <= bufptr + 48 ||
327 get_sha1_hex(bufptr + 7, parent) ||
328 bufptr[47] != '\n')
329 return error("bad parents in commit %s", sha1_to_hex(item->object.sha1));
330 bufptr += 48;
332 * The clone is shallow if nr_parent < 0, and we must
333 * not traverse its real parents even when we unhide them.
335 if (graft && (graft->nr_parent < 0 || grafts_replace_parents))
336 continue;
337 new_parent = lookup_commit(parent);
338 if (new_parent)
339 pptr = &commit_list_insert(new_parent, pptr)->next;
341 if (graft) {
342 int i;
343 struct commit *new_parent;
344 for (i = 0; i < graft->nr_parent; i++) {
345 new_parent = lookup_commit(graft->parent[i]);
346 if (!new_parent)
347 continue;
348 pptr = &commit_list_insert(new_parent, pptr)->next;
351 item->date = parse_commit_date(bufptr, tail);
353 return 0;
356 int parse_commit(struct commit *item)
358 enum object_type type;
359 void *buffer;
360 unsigned long size;
361 int ret;
363 if (!item)
364 return -1;
365 if (item->object.parsed)
366 return 0;
367 buffer = read_sha1_file(item->object.sha1, &type, &size);
368 if (!buffer)
369 return error("Could not read %s",
370 sha1_to_hex(item->object.sha1));
371 if (type != OBJ_COMMIT) {
372 free(buffer);
373 return error("Object %s not a commit",
374 sha1_to_hex(item->object.sha1));
376 ret = parse_commit_buffer(item, buffer, size);
377 if (save_commit_buffer && !ret) {
378 set_commit_buffer(item, buffer, size);
379 return 0;
381 free(buffer);
382 return ret;
385 void parse_commit_or_die(struct commit *item)
387 if (parse_commit(item))
388 die("unable to parse commit %s",
389 item ? sha1_to_hex(item->object.sha1) : "(null)");
392 int find_commit_subject(const char *commit_buffer, const char **subject)
394 const char *eol;
395 const char *p = commit_buffer;
397 while (*p && (*p != '\n' || p[1] != '\n'))
398 p++;
399 if (*p) {
400 p += 2;
401 for (eol = p; *eol && *eol != '\n'; eol++)
402 ; /* do nothing */
403 } else
404 eol = p;
406 *subject = p;
408 return eol - p;
411 struct commit_list *commit_list_insert(struct commit *item, struct commit_list **list_p)
413 struct commit_list *new_list = xmalloc(sizeof(struct commit_list));
414 new_list->item = item;
415 new_list->next = *list_p;
416 *list_p = new_list;
417 return new_list;
420 unsigned commit_list_count(const struct commit_list *l)
422 unsigned c = 0;
423 for (; l; l = l->next )
424 c++;
425 return c;
428 struct commit_list *copy_commit_list(struct commit_list *list)
430 struct commit_list *head = NULL;
431 struct commit_list **pp = &head;
432 while (list) {
433 pp = commit_list_append(list->item, pp);
434 list = list->next;
436 return head;
439 void free_commit_list(struct commit_list *list)
441 while (list) {
442 struct commit_list *temp = list;
443 list = temp->next;
444 free(temp);
448 struct commit_list * commit_list_insert_by_date(struct commit *item, struct commit_list **list)
450 struct commit_list **pp = list;
451 struct commit_list *p;
452 while ((p = *pp) != NULL) {
453 if (p->item->date < item->date) {
454 break;
456 pp = &p->next;
458 return commit_list_insert(item, pp);
461 static int commit_list_compare_by_date(const void *a, const void *b)
463 unsigned long a_date = ((const struct commit_list *)a)->item->date;
464 unsigned long b_date = ((const struct commit_list *)b)->item->date;
465 if (a_date < b_date)
466 return 1;
467 if (a_date > b_date)
468 return -1;
469 return 0;
472 static void *commit_list_get_next(const void *a)
474 return ((const struct commit_list *)a)->next;
477 static void commit_list_set_next(void *a, void *next)
479 ((struct commit_list *)a)->next = next;
482 void commit_list_sort_by_date(struct commit_list **list)
484 *list = llist_mergesort(*list, commit_list_get_next, commit_list_set_next,
485 commit_list_compare_by_date);
488 struct commit *pop_most_recent_commit(struct commit_list **list,
489 unsigned int mark)
491 struct commit *ret = (*list)->item;
492 struct commit_list *parents = ret->parents;
493 struct commit_list *old = *list;
495 *list = (*list)->next;
496 free(old);
498 while (parents) {
499 struct commit *commit = parents->item;
500 if (!parse_commit(commit) && !(commit->object.flags & mark)) {
501 commit->object.flags |= mark;
502 commit_list_insert_by_date(commit, list);
504 parents = parents->next;
506 return ret;
509 static void clear_commit_marks_1(struct commit_list **plist,
510 struct commit *commit, unsigned int mark)
512 while (commit) {
513 struct commit_list *parents;
515 if (!(mark & commit->object.flags))
516 return;
518 commit->object.flags &= ~mark;
520 parents = commit->parents;
521 if (!parents)
522 return;
524 while ((parents = parents->next))
525 commit_list_insert(parents->item, plist);
527 commit = commit->parents->item;
531 void clear_commit_marks_many(int nr, struct commit **commit, unsigned int mark)
533 struct commit_list *list = NULL;
535 while (nr--) {
536 commit_list_insert(*commit, &list);
537 commit++;
539 while (list)
540 clear_commit_marks_1(&list, pop_commit(&list), mark);
543 void clear_commit_marks(struct commit *commit, unsigned int mark)
545 clear_commit_marks_many(1, &commit, mark);
548 void clear_commit_marks_for_object_array(struct object_array *a, unsigned mark)
550 struct object *object;
551 struct commit *commit;
552 unsigned int i;
554 for (i = 0; i < a->nr; i++) {
555 object = a->objects[i].item;
556 commit = lookup_commit_reference_gently(object->sha1, 1);
557 if (commit)
558 clear_commit_marks(commit, mark);
562 struct commit *pop_commit(struct commit_list **stack)
564 struct commit_list *top = *stack;
565 struct commit *item = top ? top->item : NULL;
567 if (top) {
568 *stack = top->next;
569 free(top);
571 return item;
575 * Topological sort support
578 /* count number of children that have not been emitted */
579 define_commit_slab(indegree_slab, int);
581 /* record author-date for each commit object */
582 define_commit_slab(author_date_slab, unsigned long);
584 static void record_author_date(struct author_date_slab *author_date,
585 struct commit *commit)
587 const char *buf, *line_end, *ident_line;
588 const char *buffer = get_commit_buffer(commit, NULL);
589 struct ident_split ident;
590 char *date_end;
591 unsigned long date;
593 for (buf = buffer; buf; buf = line_end + 1) {
594 line_end = strchrnul(buf, '\n');
595 if (!skip_prefix(buf, "author ", &ident_line)) {
596 if (!line_end[0] || line_end[1] == '\n')
597 return; /* end of header */
598 continue;
600 if (split_ident_line(&ident,
601 ident_line, line_end - ident_line) ||
602 !ident.date_begin || !ident.date_end)
603 goto fail_exit; /* malformed "author" line */
604 break;
607 date = strtoul(ident.date_begin, &date_end, 10);
608 if (date_end != ident.date_end)
609 goto fail_exit; /* malformed date */
610 *(author_date_slab_at(author_date, commit)) = date;
612 fail_exit:
613 unuse_commit_buffer(commit, buffer);
616 static int compare_commits_by_author_date(const void *a_, const void *b_,
617 void *cb_data)
619 const struct commit *a = a_, *b = b_;
620 struct author_date_slab *author_date = cb_data;
621 unsigned long a_date = *(author_date_slab_at(author_date, a));
622 unsigned long b_date = *(author_date_slab_at(author_date, b));
624 /* newer commits with larger date first */
625 if (a_date < b_date)
626 return 1;
627 else if (a_date > b_date)
628 return -1;
629 return 0;
632 int compare_commits_by_commit_date(const void *a_, const void *b_, void *unused)
634 const struct commit *a = a_, *b = b_;
635 /* newer commits with larger date first */
636 if (a->date < b->date)
637 return 1;
638 else if (a->date > b->date)
639 return -1;
640 return 0;
644 * Performs an in-place topological sort on the list supplied.
646 void sort_in_topological_order(struct commit_list **list, enum rev_sort_order sort_order)
648 struct commit_list *next, *orig = *list;
649 struct commit_list **pptr;
650 struct indegree_slab indegree;
651 struct prio_queue queue;
652 struct commit *commit;
653 struct author_date_slab author_date;
655 if (!orig)
656 return;
657 *list = NULL;
659 init_indegree_slab(&indegree);
660 memset(&queue, '\0', sizeof(queue));
662 switch (sort_order) {
663 default: /* REV_SORT_IN_GRAPH_ORDER */
664 queue.compare = NULL;
665 break;
666 case REV_SORT_BY_COMMIT_DATE:
667 queue.compare = compare_commits_by_commit_date;
668 break;
669 case REV_SORT_BY_AUTHOR_DATE:
670 init_author_date_slab(&author_date);
671 queue.compare = compare_commits_by_author_date;
672 queue.cb_data = &author_date;
673 break;
676 /* Mark them and clear the indegree */
677 for (next = orig; next; next = next->next) {
678 struct commit *commit = next->item;
679 *(indegree_slab_at(&indegree, commit)) = 1;
680 /* also record the author dates, if needed */
681 if (sort_order == REV_SORT_BY_AUTHOR_DATE)
682 record_author_date(&author_date, commit);
685 /* update the indegree */
686 for (next = orig; next; next = next->next) {
687 struct commit_list *parents = next->item->parents;
688 while (parents) {
689 struct commit *parent = parents->item;
690 int *pi = indegree_slab_at(&indegree, parent);
692 if (*pi)
693 (*pi)++;
694 parents = parents->next;
699 * find the tips
701 * tips are nodes not reachable from any other node in the list
703 * the tips serve as a starting set for the work queue.
705 for (next = orig; next; next = next->next) {
706 struct commit *commit = next->item;
708 if (*(indegree_slab_at(&indegree, commit)) == 1)
709 prio_queue_put(&queue, commit);
713 * This is unfortunate; the initial tips need to be shown
714 * in the order given from the revision traversal machinery.
716 if (sort_order == REV_SORT_IN_GRAPH_ORDER)
717 prio_queue_reverse(&queue);
719 /* We no longer need the commit list */
720 free_commit_list(orig);
722 pptr = list;
723 *list = NULL;
724 while ((commit = prio_queue_get(&queue)) != NULL) {
725 struct commit_list *parents;
727 for (parents = commit->parents; parents ; parents = parents->next) {
728 struct commit *parent = parents->item;
729 int *pi = indegree_slab_at(&indegree, parent);
731 if (!*pi)
732 continue;
735 * parents are only enqueued for emission
736 * when all their children have been emitted thereby
737 * guaranteeing topological order.
739 if (--(*pi) == 1)
740 prio_queue_put(&queue, parent);
743 * all children of commit have already been
744 * emitted. we can emit it now.
746 *(indegree_slab_at(&indegree, commit)) = 0;
748 pptr = &commit_list_insert(commit, pptr)->next;
751 clear_indegree_slab(&indegree);
752 clear_prio_queue(&queue);
753 if (sort_order == REV_SORT_BY_AUTHOR_DATE)
754 clear_author_date_slab(&author_date);
757 /* merge-base stuff */
759 /* Remember to update object flag allocation in object.h */
760 #define PARENT1 (1u<<16)
761 #define PARENT2 (1u<<17)
762 #define STALE (1u<<18)
763 #define RESULT (1u<<19)
765 static const unsigned all_flags = (PARENT1 | PARENT2 | STALE | RESULT);
767 static struct commit *interesting(struct commit_list *list)
769 while (list) {
770 struct commit *commit = list->item;
771 list = list->next;
772 if (commit->object.flags & STALE)
773 continue;
774 return commit;
776 return NULL;
779 /* all input commits in one and twos[] must have been parsed! */
780 static struct commit_list *paint_down_to_common(struct commit *one, int n, struct commit **twos)
782 struct commit_list *list = NULL;
783 struct commit_list *result = NULL;
784 int i;
786 one->object.flags |= PARENT1;
787 commit_list_insert_by_date(one, &list);
788 if (!n)
789 return list;
790 for (i = 0; i < n; i++) {
791 twos[i]->object.flags |= PARENT2;
792 commit_list_insert_by_date(twos[i], &list);
795 while (interesting(list)) {
796 struct commit *commit;
797 struct commit_list *parents;
798 struct commit_list *next;
799 int flags;
801 commit = list->item;
802 next = list->next;
803 free(list);
804 list = next;
806 flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
807 if (flags == (PARENT1 | PARENT2)) {
808 if (!(commit->object.flags & RESULT)) {
809 commit->object.flags |= RESULT;
810 commit_list_insert_by_date(commit, &result);
812 /* Mark parents of a found merge stale */
813 flags |= STALE;
815 parents = commit->parents;
816 while (parents) {
817 struct commit *p = parents->item;
818 parents = parents->next;
819 if ((p->object.flags & flags) == flags)
820 continue;
821 if (parse_commit(p))
822 return NULL;
823 p->object.flags |= flags;
824 commit_list_insert_by_date(p, &list);
828 free_commit_list(list);
829 return result;
832 static struct commit_list *merge_bases_many(struct commit *one, int n, struct commit **twos)
834 struct commit_list *list = NULL;
835 struct commit_list *result = NULL;
836 int i;
838 for (i = 0; i < n; i++) {
839 if (one == twos[i])
841 * We do not mark this even with RESULT so we do not
842 * have to clean it up.
844 return commit_list_insert(one, &result);
847 if (parse_commit(one))
848 return NULL;
849 for (i = 0; i < n; i++) {
850 if (parse_commit(twos[i]))
851 return NULL;
854 list = paint_down_to_common(one, n, twos);
856 while (list) {
857 struct commit_list *next = list->next;
858 if (!(list->item->object.flags & STALE))
859 commit_list_insert_by_date(list->item, &result);
860 free(list);
861 list = next;
863 return result;
866 struct commit_list *get_octopus_merge_bases(struct commit_list *in)
868 struct commit_list *i, *j, *k, *ret = NULL;
870 if (!in)
871 return ret;
873 commit_list_insert(in->item, &ret);
875 for (i = in->next; i; i = i->next) {
876 struct commit_list *new = NULL, *end = NULL;
878 for (j = ret; j; j = j->next) {
879 struct commit_list *bases;
880 bases = get_merge_bases(i->item, j->item, 1);
881 if (!new)
882 new = bases;
883 else
884 end->next = bases;
885 for (k = bases; k; k = k->next)
886 end = k;
888 ret = new;
890 return ret;
893 static int remove_redundant(struct commit **array, int cnt)
896 * Some commit in the array may be an ancestor of
897 * another commit. Move such commit to the end of
898 * the array, and return the number of commits that
899 * are independent from each other.
901 struct commit **work;
902 unsigned char *redundant;
903 int *filled_index;
904 int i, j, filled;
906 work = xcalloc(cnt, sizeof(*work));
907 redundant = xcalloc(cnt, 1);
908 filled_index = xmalloc(sizeof(*filled_index) * (cnt - 1));
910 for (i = 0; i < cnt; i++)
911 parse_commit(array[i]);
912 for (i = 0; i < cnt; i++) {
913 struct commit_list *common;
915 if (redundant[i])
916 continue;
917 for (j = filled = 0; j < cnt; j++) {
918 if (i == j || redundant[j])
919 continue;
920 filled_index[filled] = j;
921 work[filled++] = array[j];
923 common = paint_down_to_common(array[i], filled, work);
924 if (array[i]->object.flags & PARENT2)
925 redundant[i] = 1;
926 for (j = 0; j < filled; j++)
927 if (work[j]->object.flags & PARENT1)
928 redundant[filled_index[j]] = 1;
929 clear_commit_marks(array[i], all_flags);
930 for (j = 0; j < filled; j++)
931 clear_commit_marks(work[j], all_flags);
932 free_commit_list(common);
935 /* Now collect the result */
936 memcpy(work, array, sizeof(*array) * cnt);
937 for (i = filled = 0; i < cnt; i++)
938 if (!redundant[i])
939 array[filled++] = work[i];
940 for (j = filled, i = 0; i < cnt; i++)
941 if (redundant[i])
942 array[j++] = work[i];
943 free(work);
944 free(redundant);
945 free(filled_index);
946 return filled;
949 struct commit_list *get_merge_bases_many(struct commit *one,
950 int n,
951 struct commit **twos,
952 int cleanup)
954 struct commit_list *list;
955 struct commit **rslt;
956 struct commit_list *result;
957 int cnt, i;
959 result = merge_bases_many(one, n, twos);
960 for (i = 0; i < n; i++) {
961 if (one == twos[i])
962 return result;
964 if (!result || !result->next) {
965 if (cleanup) {
966 clear_commit_marks(one, all_flags);
967 clear_commit_marks_many(n, twos, all_flags);
969 return result;
972 /* There are more than one */
973 cnt = commit_list_count(result);
974 rslt = xcalloc(cnt, sizeof(*rslt));
975 for (list = result, i = 0; list; list = list->next)
976 rslt[i++] = list->item;
977 free_commit_list(result);
979 clear_commit_marks(one, all_flags);
980 clear_commit_marks_many(n, twos, all_flags);
982 cnt = remove_redundant(rslt, cnt);
983 result = NULL;
984 for (i = 0; i < cnt; i++)
985 commit_list_insert_by_date(rslt[i], &result);
986 free(rslt);
987 return result;
990 struct commit_list *get_merge_bases(struct commit *one, struct commit *two,
991 int cleanup)
993 return get_merge_bases_many(one, 1, &two, cleanup);
997 * Is "commit" a descendant of one of the elements on the "with_commit" list?
999 int is_descendant_of(struct commit *commit, struct commit_list *with_commit)
1001 if (!with_commit)
1002 return 1;
1003 while (with_commit) {
1004 struct commit *other;
1006 other = with_commit->item;
1007 with_commit = with_commit->next;
1008 if (in_merge_bases(other, commit))
1009 return 1;
1011 return 0;
1015 * Is "commit" an ancestor of one of the "references"?
1017 int in_merge_bases_many(struct commit *commit, int nr_reference, struct commit **reference)
1019 struct commit_list *bases;
1020 int ret = 0, i;
1022 if (parse_commit(commit))
1023 return ret;
1024 for (i = 0; i < nr_reference; i++)
1025 if (parse_commit(reference[i]))
1026 return ret;
1028 bases = paint_down_to_common(commit, nr_reference, reference);
1029 if (commit->object.flags & PARENT2)
1030 ret = 1;
1031 clear_commit_marks(commit, all_flags);
1032 clear_commit_marks_many(nr_reference, reference, all_flags);
1033 free_commit_list(bases);
1034 return ret;
1038 * Is "commit" an ancestor of (i.e. reachable from) the "reference"?
1040 int in_merge_bases(struct commit *commit, struct commit *reference)
1042 return in_merge_bases_many(commit, 1, &reference);
1045 struct commit_list *reduce_heads(struct commit_list *heads)
1047 struct commit_list *p;
1048 struct commit_list *result = NULL, **tail = &result;
1049 struct commit **array;
1050 int num_head, i;
1052 if (!heads)
1053 return NULL;
1055 /* Uniquify */
1056 for (p = heads; p; p = p->next)
1057 p->item->object.flags &= ~STALE;
1058 for (p = heads, num_head = 0; p; p = p->next) {
1059 if (p->item->object.flags & STALE)
1060 continue;
1061 p->item->object.flags |= STALE;
1062 num_head++;
1064 array = xcalloc(num_head, sizeof(*array));
1065 for (p = heads, i = 0; p; p = p->next) {
1066 if (p->item->object.flags & STALE) {
1067 array[i++] = p->item;
1068 p->item->object.flags &= ~STALE;
1071 num_head = remove_redundant(array, num_head);
1072 for (i = 0; i < num_head; i++)
1073 tail = &commit_list_insert(array[i], tail)->next;
1074 return result;
1077 static const char gpg_sig_header[] = "gpgsig";
1078 static const int gpg_sig_header_len = sizeof(gpg_sig_header) - 1;
1080 static int do_sign_commit(struct strbuf *buf, const char *keyid)
1082 struct strbuf sig = STRBUF_INIT;
1083 int inspos, copypos;
1085 /* find the end of the header */
1086 inspos = strstr(buf->buf, "\n\n") - buf->buf + 1;
1088 if (!keyid || !*keyid)
1089 keyid = get_signing_key();
1090 if (sign_buffer(buf, &sig, keyid)) {
1091 strbuf_release(&sig);
1092 return -1;
1095 for (copypos = 0; sig.buf[copypos]; ) {
1096 const char *bol = sig.buf + copypos;
1097 const char *eol = strchrnul(bol, '\n');
1098 int len = (eol - bol) + !!*eol;
1100 if (!copypos) {
1101 strbuf_insert(buf, inspos, gpg_sig_header, gpg_sig_header_len);
1102 inspos += gpg_sig_header_len;
1104 strbuf_insert(buf, inspos++, " ", 1);
1105 strbuf_insert(buf, inspos, bol, len);
1106 inspos += len;
1107 copypos += len;
1109 strbuf_release(&sig);
1110 return 0;
1113 int parse_signed_commit(const struct commit *commit,
1114 struct strbuf *payload, struct strbuf *signature)
1117 unsigned long size;
1118 const char *buffer = get_commit_buffer(commit, &size);
1119 int in_signature, saw_signature = -1;
1120 const char *line, *tail;
1122 line = buffer;
1123 tail = buffer + size;
1124 in_signature = 0;
1125 saw_signature = 0;
1126 while (line < tail) {
1127 const char *sig = NULL;
1128 const char *next = memchr(line, '\n', tail - line);
1130 next = next ? next + 1 : tail;
1131 if (in_signature && line[0] == ' ')
1132 sig = line + 1;
1133 else if (starts_with(line, gpg_sig_header) &&
1134 line[gpg_sig_header_len] == ' ')
1135 sig = line + gpg_sig_header_len + 1;
1136 if (sig) {
1137 strbuf_add(signature, sig, next - sig);
1138 saw_signature = 1;
1139 in_signature = 1;
1140 } else {
1141 if (*line == '\n')
1142 /* dump the whole remainder of the buffer */
1143 next = tail;
1144 strbuf_add(payload, line, next - line);
1145 in_signature = 0;
1147 line = next;
1149 unuse_commit_buffer(commit, buffer);
1150 return saw_signature;
1153 static void handle_signed_tag(struct commit *parent, struct commit_extra_header ***tail)
1155 struct merge_remote_desc *desc;
1156 struct commit_extra_header *mergetag;
1157 char *buf;
1158 unsigned long size, len;
1159 enum object_type type;
1161 desc = merge_remote_util(parent);
1162 if (!desc || !desc->obj)
1163 return;
1164 buf = read_sha1_file(desc->obj->sha1, &type, &size);
1165 if (!buf || type != OBJ_TAG)
1166 goto free_return;
1167 len = parse_signature(buf, size);
1168 if (size == len)
1169 goto free_return;
1171 * We could verify this signature and either omit the tag when
1172 * it does not validate, but the integrator may not have the
1173 * public key of the signer of the tag he is merging, while a
1174 * later auditor may have it while auditing, so let's not run
1175 * verify-signed-buffer here for now...
1177 * if (verify_signed_buffer(buf, len, buf + len, size - len, ...))
1178 * warn("warning: signed tag unverified.");
1180 mergetag = xcalloc(1, sizeof(*mergetag));
1181 mergetag->key = xstrdup("mergetag");
1182 mergetag->value = buf;
1183 mergetag->len = size;
1185 **tail = mergetag;
1186 *tail = &mergetag->next;
1187 return;
1189 free_return:
1190 free(buf);
1193 static struct {
1194 char result;
1195 const char *check;
1196 } sigcheck_gpg_status[] = {
1197 { 'G', "\n[GNUPG:] GOODSIG " },
1198 { 'B', "\n[GNUPG:] BADSIG " },
1199 { 'U', "\n[GNUPG:] TRUST_NEVER" },
1200 { 'U', "\n[GNUPG:] TRUST_UNDEFINED" },
1203 static void parse_gpg_output(struct signature_check *sigc)
1205 const char *buf = sigc->gpg_status;
1206 int i;
1208 /* Iterate over all search strings */
1209 for (i = 0; i < ARRAY_SIZE(sigcheck_gpg_status); i++) {
1210 const char *found, *next;
1212 if (!skip_prefix(buf, sigcheck_gpg_status[i].check + 1, &found)) {
1213 found = strstr(buf, sigcheck_gpg_status[i].check);
1214 if (!found)
1215 continue;
1216 found += strlen(sigcheck_gpg_status[i].check);
1218 sigc->result = sigcheck_gpg_status[i].result;
1219 /* The trust messages are not followed by key/signer information */
1220 if (sigc->result != 'U') {
1221 sigc->key = xmemdupz(found, 16);
1222 found += 17;
1223 next = strchrnul(found, '\n');
1224 sigc->signer = xmemdupz(found, next - found);
1229 void check_commit_signature(const struct commit* commit, struct signature_check *sigc)
1231 struct strbuf payload = STRBUF_INIT;
1232 struct strbuf signature = STRBUF_INIT;
1233 struct strbuf gpg_output = STRBUF_INIT;
1234 struct strbuf gpg_status = STRBUF_INIT;
1235 int status;
1237 sigc->result = 'N';
1239 if (parse_signed_commit(commit, &payload, &signature) <= 0)
1240 goto out;
1241 status = verify_signed_buffer(payload.buf, payload.len,
1242 signature.buf, signature.len,
1243 &gpg_output, &gpg_status);
1244 if (status && !gpg_output.len)
1245 goto out;
1246 sigc->payload = strbuf_detach(&payload, NULL);
1247 sigc->gpg_output = strbuf_detach(&gpg_output, NULL);
1248 sigc->gpg_status = strbuf_detach(&gpg_status, NULL);
1249 parse_gpg_output(sigc);
1251 out:
1252 strbuf_release(&gpg_status);
1253 strbuf_release(&gpg_output);
1254 strbuf_release(&payload);
1255 strbuf_release(&signature);
1260 void append_merge_tag_headers(struct commit_list *parents,
1261 struct commit_extra_header ***tail)
1263 while (parents) {
1264 struct commit *parent = parents->item;
1265 handle_signed_tag(parent, tail);
1266 parents = parents->next;
1270 static void add_extra_header(struct strbuf *buffer,
1271 struct commit_extra_header *extra)
1273 strbuf_addstr(buffer, extra->key);
1274 if (extra->len)
1275 strbuf_add_lines(buffer, " ", extra->value, extra->len);
1276 else
1277 strbuf_addch(buffer, '\n');
1280 struct commit_extra_header *read_commit_extra_headers(struct commit *commit,
1281 const char **exclude)
1283 struct commit_extra_header *extra = NULL;
1284 unsigned long size;
1285 const char *buffer = get_commit_buffer(commit, &size);
1286 extra = read_commit_extra_header_lines(buffer, size, exclude);
1287 unuse_commit_buffer(commit, buffer);
1288 return extra;
1291 void for_each_mergetag(each_mergetag_fn fn, struct commit *commit, void *data)
1293 struct commit_extra_header *extra, *to_free;
1295 to_free = read_commit_extra_headers(commit, NULL);
1296 for (extra = to_free; extra; extra = extra->next) {
1297 if (strcmp(extra->key, "mergetag"))
1298 continue; /* not a merge tag */
1299 fn(commit, extra, data);
1301 free_commit_extra_headers(to_free);
1304 static inline int standard_header_field(const char *field, size_t len)
1306 return ((len == 4 && !memcmp(field, "tree ", 5)) ||
1307 (len == 6 && !memcmp(field, "parent ", 7)) ||
1308 (len == 6 && !memcmp(field, "author ", 7)) ||
1309 (len == 9 && !memcmp(field, "committer ", 10)) ||
1310 (len == 8 && !memcmp(field, "encoding ", 9)));
1313 static int excluded_header_field(const char *field, size_t len, const char **exclude)
1315 if (!exclude)
1316 return 0;
1318 while (*exclude) {
1319 size_t xlen = strlen(*exclude);
1320 if (len == xlen &&
1321 !memcmp(field, *exclude, xlen) && field[xlen] == ' ')
1322 return 1;
1323 exclude++;
1325 return 0;
1328 static struct commit_extra_header *read_commit_extra_header_lines(
1329 const char *buffer, size_t size,
1330 const char **exclude)
1332 struct commit_extra_header *extra = NULL, **tail = &extra, *it = NULL;
1333 const char *line, *next, *eof, *eob;
1334 struct strbuf buf = STRBUF_INIT;
1336 for (line = buffer, eob = line + size;
1337 line < eob && *line != '\n';
1338 line = next) {
1339 next = memchr(line, '\n', eob - line);
1340 next = next ? next + 1 : eob;
1341 if (*line == ' ') {
1342 /* continuation */
1343 if (it)
1344 strbuf_add(&buf, line + 1, next - (line + 1));
1345 continue;
1347 if (it)
1348 it->value = strbuf_detach(&buf, &it->len);
1349 strbuf_reset(&buf);
1350 it = NULL;
1352 eof = strchr(line, ' ');
1353 if (next <= eof)
1354 eof = next;
1356 if (standard_header_field(line, eof - line) ||
1357 excluded_header_field(line, eof - line, exclude))
1358 continue;
1360 it = xcalloc(1, sizeof(*it));
1361 it->key = xmemdupz(line, eof-line);
1362 *tail = it;
1363 tail = &it->next;
1364 if (eof + 1 < next)
1365 strbuf_add(&buf, eof + 1, next - (eof + 1));
1367 if (it)
1368 it->value = strbuf_detach(&buf, &it->len);
1369 return extra;
1372 void free_commit_extra_headers(struct commit_extra_header *extra)
1374 while (extra) {
1375 struct commit_extra_header *next = extra->next;
1376 free(extra->key);
1377 free(extra->value);
1378 free(extra);
1379 extra = next;
1383 int commit_tree(const char *msg, size_t msg_len,
1384 const unsigned char *tree,
1385 struct commit_list *parents, unsigned char *ret,
1386 const char *author, const char *sign_commit)
1388 struct commit_extra_header *extra = NULL, **tail = &extra;
1389 int result;
1391 append_merge_tag_headers(parents, &tail);
1392 result = commit_tree_extended(msg, msg_len, tree, parents, ret,
1393 author, sign_commit, extra);
1394 free_commit_extra_headers(extra);
1395 return result;
1398 static int find_invalid_utf8(const char *buf, int len)
1400 int offset = 0;
1401 static const unsigned int max_codepoint[] = {
1402 0x7f, 0x7ff, 0xffff, 0x10ffff
1405 while (len) {
1406 unsigned char c = *buf++;
1407 int bytes, bad_offset;
1408 unsigned int codepoint;
1409 unsigned int min_val, max_val;
1411 len--;
1412 offset++;
1414 /* Simple US-ASCII? No worries. */
1415 if (c < 0x80)
1416 continue;
1418 bad_offset = offset-1;
1421 * Count how many more high bits set: that's how
1422 * many more bytes this sequence should have.
1424 bytes = 0;
1425 while (c & 0x40) {
1426 c <<= 1;
1427 bytes++;
1431 * Must be between 1 and 3 more bytes. Longer sequences result in
1432 * codepoints beyond U+10FFFF, which are guaranteed never to exist.
1434 if (bytes < 1 || 3 < bytes)
1435 return bad_offset;
1437 /* Do we *have* that many bytes? */
1438 if (len < bytes)
1439 return bad_offset;
1442 * Place the encoded bits at the bottom of the value and compute the
1443 * valid range.
1445 codepoint = (c & 0x7f) >> bytes;
1446 min_val = max_codepoint[bytes-1] + 1;
1447 max_val = max_codepoint[bytes];
1449 offset += bytes;
1450 len -= bytes;
1452 /* And verify that they are good continuation bytes */
1453 do {
1454 codepoint <<= 6;
1455 codepoint |= *buf & 0x3f;
1456 if ((*buf++ & 0xc0) != 0x80)
1457 return bad_offset;
1458 } while (--bytes);
1460 /* Reject codepoints that are out of range for the sequence length. */
1461 if (codepoint < min_val || codepoint > max_val)
1462 return bad_offset;
1463 /* Surrogates are only for UTF-16 and cannot be encoded in UTF-8. */
1464 if ((codepoint & 0x1ff800) == 0xd800)
1465 return bad_offset;
1466 /* U+xxFFFE and U+xxFFFF are guaranteed non-characters. */
1467 if ((codepoint & 0xfffe) == 0xfffe)
1468 return bad_offset;
1469 /* So are anything in the range U+FDD0..U+FDEF. */
1470 if (codepoint >= 0xfdd0 && codepoint <= 0xfdef)
1471 return bad_offset;
1473 return -1;
1477 * This verifies that the buffer is in proper utf8 format.
1479 * If it isn't, it assumes any non-utf8 characters are Latin1,
1480 * and does the conversion.
1482 static int verify_utf8(struct strbuf *buf)
1484 int ok = 1;
1485 long pos = 0;
1487 for (;;) {
1488 int bad;
1489 unsigned char c;
1490 unsigned char replace[2];
1492 bad = find_invalid_utf8(buf->buf + pos, buf->len - pos);
1493 if (bad < 0)
1494 return ok;
1495 pos += bad;
1496 ok = 0;
1497 c = buf->buf[pos];
1498 strbuf_remove(buf, pos, 1);
1500 /* We know 'c' must be in the range 128-255 */
1501 replace[0] = 0xc0 + (c >> 6);
1502 replace[1] = 0x80 + (c & 0x3f);
1503 strbuf_insert(buf, pos, replace, 2);
1504 pos += 2;
1508 static const char commit_utf8_warn[] =
1509 "Warning: commit message did not conform to UTF-8.\n"
1510 "You may want to amend it after fixing the message, or set the config\n"
1511 "variable i18n.commitencoding to the encoding your project uses.\n";
1513 int commit_tree_extended(const char *msg, size_t msg_len,
1514 const unsigned char *tree,
1515 struct commit_list *parents, unsigned char *ret,
1516 const char *author, const char *sign_commit,
1517 struct commit_extra_header *extra)
1519 int result;
1520 int encoding_is_utf8;
1521 struct strbuf buffer;
1523 assert_sha1_type(tree, OBJ_TREE);
1525 if (memchr(msg, '\0', msg_len))
1526 return error("a NUL byte in commit log message not allowed.");
1528 /* Not having i18n.commitencoding is the same as having utf-8 */
1529 encoding_is_utf8 = is_encoding_utf8(git_commit_encoding);
1531 strbuf_init(&buffer, 8192); /* should avoid reallocs for the headers */
1532 strbuf_addf(&buffer, "tree %s\n", sha1_to_hex(tree));
1535 * NOTE! This ordering means that the same exact tree merged with a
1536 * different order of parents will be a _different_ changeset even
1537 * if everything else stays the same.
1539 while (parents) {
1540 struct commit_list *next = parents->next;
1541 struct commit *parent = parents->item;
1543 strbuf_addf(&buffer, "parent %s\n",
1544 sha1_to_hex(parent->object.sha1));
1545 free(parents);
1546 parents = next;
1549 /* Person/date information */
1550 if (!author)
1551 author = git_author_info(IDENT_STRICT);
1552 strbuf_addf(&buffer, "author %s\n", author);
1553 strbuf_addf(&buffer, "committer %s\n", git_committer_info(IDENT_STRICT));
1554 if (!encoding_is_utf8)
1555 strbuf_addf(&buffer, "encoding %s\n", git_commit_encoding);
1557 while (extra) {
1558 add_extra_header(&buffer, extra);
1559 extra = extra->next;
1561 strbuf_addch(&buffer, '\n');
1563 /* And add the comment */
1564 strbuf_add(&buffer, msg, msg_len);
1566 /* And check the encoding */
1567 if (encoding_is_utf8 && !verify_utf8(&buffer))
1568 fprintf(stderr, commit_utf8_warn);
1570 if (sign_commit && do_sign_commit(&buffer, sign_commit))
1571 return -1;
1573 result = write_sha1_file(buffer.buf, buffer.len, commit_type, ret);
1574 strbuf_release(&buffer);
1575 return result;
1578 struct commit *get_merge_parent(const char *name)
1580 struct object *obj;
1581 struct commit *commit;
1582 unsigned char sha1[20];
1583 if (get_sha1(name, sha1))
1584 return NULL;
1585 obj = parse_object(sha1);
1586 commit = (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
1587 if (commit && !commit->util) {
1588 struct merge_remote_desc *desc;
1589 desc = xmalloc(sizeof(*desc));
1590 desc->obj = obj;
1591 desc->name = strdup(name);
1592 commit->util = desc;
1594 return commit;
1598 * Append a commit to the end of the commit_list.
1600 * next starts by pointing to the variable that holds the head of an
1601 * empty commit_list, and is updated to point to the "next" field of
1602 * the last item on the list as new commits are appended.
1604 * Usage example:
1606 * struct commit_list *list;
1607 * struct commit_list **next = &list;
1609 * next = commit_list_append(c1, next);
1610 * next = commit_list_append(c2, next);
1611 * assert(commit_list_count(list) == 2);
1612 * return list;
1614 struct commit_list **commit_list_append(struct commit *commit,
1615 struct commit_list **next)
1617 struct commit_list *new = xmalloc(sizeof(struct commit_list));
1618 new->item = commit;
1619 *next = new;
1620 new->next = NULL;
1621 return &new->next;
1624 void print_commit_list(struct commit_list *list,
1625 const char *format_cur,
1626 const char *format_last)
1628 for ( ; list; list = list->next) {
1629 const char *format = list->next ? format_cur : format_last;
1630 printf(format, sha1_to_hex(list->item->object.sha1));