diff-options.txt: describe --stat-{width,name-width,count}
[git/dscho.git] / commit.c
blobac337c7d7dc1724fa918f9340816d3102edb10bd
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"
10 int save_commit_buffer = 1;
12 const char *commit_type = "commit";
14 static struct commit *check_commit(struct object *obj,
15 const unsigned char *sha1,
16 int quiet)
18 if (obj->type != OBJ_COMMIT) {
19 if (!quiet)
20 error("Object %s is a %s, not a commit",
21 sha1_to_hex(sha1), typename(obj->type));
22 return NULL;
24 return (struct commit *) obj;
27 struct commit *lookup_commit_reference_gently(const unsigned char *sha1,
28 int quiet)
30 struct object *obj = deref_tag(parse_object(sha1), NULL, 0);
32 if (!obj)
33 return NULL;
34 return check_commit(obj, sha1, quiet);
37 struct commit *lookup_commit_reference(const unsigned char *sha1)
39 return lookup_commit_reference_gently(sha1, 0);
42 struct commit *lookup_commit(const unsigned char *sha1)
44 struct object *obj = lookup_object(sha1);
45 if (!obj)
46 return create_object(sha1, OBJ_COMMIT, alloc_commit_node());
47 if (!obj->type)
48 obj->type = OBJ_COMMIT;
49 return check_commit(obj, sha1, 0);
52 struct commit *lookup_commit_reference_by_name(const char *name)
54 unsigned char sha1[20];
55 struct commit *commit;
57 if (get_sha1(name, sha1))
58 return NULL;
59 commit = lookup_commit_reference(sha1);
60 if (!commit || parse_commit(commit))
61 return NULL;
62 return commit;
65 static unsigned long parse_commit_date(const char *buf, const char *tail)
67 const char *dateptr;
69 if (buf + 6 >= tail)
70 return 0;
71 if (memcmp(buf, "author", 6))
72 return 0;
73 while (buf < tail && *buf++ != '\n')
74 /* nada */;
75 if (buf + 9 >= tail)
76 return 0;
77 if (memcmp(buf, "committer", 9))
78 return 0;
79 while (buf < tail && *buf++ != '>')
80 /* nada */;
81 if (buf >= tail)
82 return 0;
83 dateptr = buf;
84 while (buf < tail && *buf++ != '\n')
85 /* nada */;
86 if (buf >= tail)
87 return 0;
88 /* dateptr < buf && buf[-1] == '\n', so strtoul will stop at buf-1 */
89 return strtoul(dateptr, NULL, 10);
92 static struct commit_graft **commit_graft;
93 static int commit_graft_alloc, commit_graft_nr;
95 static int commit_graft_pos(const unsigned char *sha1)
97 int lo, hi;
98 lo = 0;
99 hi = commit_graft_nr;
100 while (lo < hi) {
101 int mi = (lo + hi) / 2;
102 struct commit_graft *graft = commit_graft[mi];
103 int cmp = hashcmp(sha1, graft->sha1);
104 if (!cmp)
105 return mi;
106 if (cmp < 0)
107 hi = mi;
108 else
109 lo = mi + 1;
111 return -lo - 1;
114 int register_commit_graft(struct commit_graft *graft, int ignore_dups)
116 int pos = commit_graft_pos(graft->sha1);
118 if (0 <= pos) {
119 if (ignore_dups)
120 free(graft);
121 else {
122 free(commit_graft[pos]);
123 commit_graft[pos] = graft;
125 return 1;
127 pos = -pos - 1;
128 if (commit_graft_alloc <= ++commit_graft_nr) {
129 commit_graft_alloc = alloc_nr(commit_graft_alloc);
130 commit_graft = xrealloc(commit_graft,
131 sizeof(*commit_graft) *
132 commit_graft_alloc);
134 if (pos < commit_graft_nr)
135 memmove(commit_graft + pos + 1,
136 commit_graft + pos,
137 (commit_graft_nr - pos - 1) *
138 sizeof(*commit_graft));
139 commit_graft[pos] = graft;
140 return 0;
143 struct commit_graft *read_graft_line(char *buf, int len)
145 /* The format is just "Commit Parent1 Parent2 ...\n" */
146 int i;
147 struct commit_graft *graft = NULL;
149 while (len && isspace(buf[len-1]))
150 buf[--len] = '\0';
151 if (buf[0] == '#' || buf[0] == '\0')
152 return NULL;
153 if ((len + 1) % 41)
154 goto bad_graft_data;
155 i = (len + 1) / 41 - 1;
156 graft = xmalloc(sizeof(*graft) + 20 * i);
157 graft->nr_parent = i;
158 if (get_sha1_hex(buf, graft->sha1))
159 goto bad_graft_data;
160 for (i = 40; i < len; i += 41) {
161 if (buf[i] != ' ')
162 goto bad_graft_data;
163 if (get_sha1_hex(buf + i + 1, graft->parent[i/41]))
164 goto bad_graft_data;
166 return graft;
168 bad_graft_data:
169 error("bad graft data: %s", buf);
170 free(graft);
171 return NULL;
174 static int read_graft_file(const char *graft_file)
176 FILE *fp = fopen(graft_file, "r");
177 char buf[1024];
178 if (!fp)
179 return -1;
180 while (fgets(buf, sizeof(buf), fp)) {
181 /* The format is just "Commit Parent1 Parent2 ...\n" */
182 int len = strlen(buf);
183 struct commit_graft *graft = read_graft_line(buf, len);
184 if (!graft)
185 continue;
186 if (register_commit_graft(graft, 1))
187 error("duplicate graft data: %s", buf);
189 fclose(fp);
190 return 0;
193 static void prepare_commit_graft(void)
195 static int commit_graft_prepared;
196 char *graft_file;
198 if (commit_graft_prepared)
199 return;
200 graft_file = get_graft_file();
201 read_graft_file(graft_file);
202 /* make sure shallows are read */
203 is_repository_shallow();
204 commit_graft_prepared = 1;
207 struct commit_graft *lookup_commit_graft(const unsigned char *sha1)
209 int pos;
210 prepare_commit_graft();
211 pos = commit_graft_pos(sha1);
212 if (pos < 0)
213 return NULL;
214 return commit_graft[pos];
217 int write_shallow_commits(struct strbuf *out, int use_pack_protocol)
219 int i, count = 0;
220 for (i = 0; i < commit_graft_nr; i++)
221 if (commit_graft[i]->nr_parent < 0) {
222 const char *hex =
223 sha1_to_hex(commit_graft[i]->sha1);
224 count++;
225 if (use_pack_protocol)
226 packet_buf_write(out, "shallow %s", hex);
227 else {
228 strbuf_addstr(out, hex);
229 strbuf_addch(out, '\n');
232 return count;
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 int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long size)
250 const char *tail = buffer;
251 const char *bufptr = buffer;
252 unsigned char parent[20];
253 struct commit_list **pptr;
254 struct commit_graft *graft;
256 if (item->object.parsed)
257 return 0;
258 item->object.parsed = 1;
259 tail += size;
260 if (tail <= bufptr + 46 || memcmp(bufptr, "tree ", 5) || bufptr[45] != '\n')
261 return error("bogus commit object %s", sha1_to_hex(item->object.sha1));
262 if (get_sha1_hex(bufptr + 5, parent) < 0)
263 return error("bad tree pointer in commit %s",
264 sha1_to_hex(item->object.sha1));
265 item->tree = lookup_tree(parent);
266 bufptr += 46; /* "tree " + "hex sha1" + "\n" */
267 pptr = &item->parents;
269 graft = lookup_commit_graft(item->object.sha1);
270 while (bufptr + 48 < tail && !memcmp(bufptr, "parent ", 7)) {
271 struct commit *new_parent;
273 if (tail <= bufptr + 48 ||
274 get_sha1_hex(bufptr + 7, parent) ||
275 bufptr[47] != '\n')
276 return error("bad parents in commit %s", sha1_to_hex(item->object.sha1));
277 bufptr += 48;
279 * The clone is shallow if nr_parent < 0, and we must
280 * not traverse its real parents even when we unhide them.
282 if (graft && (graft->nr_parent < 0 || grafts_replace_parents))
283 continue;
284 new_parent = lookup_commit(parent);
285 if (new_parent)
286 pptr = &commit_list_insert(new_parent, pptr)->next;
288 if (graft) {
289 int i;
290 struct commit *new_parent;
291 for (i = 0; i < graft->nr_parent; i++) {
292 new_parent = lookup_commit(graft->parent[i]);
293 if (!new_parent)
294 continue;
295 pptr = &commit_list_insert(new_parent, pptr)->next;
298 item->date = parse_commit_date(bufptr, tail);
300 return 0;
303 int parse_commit(struct commit *item)
305 enum object_type type;
306 void *buffer;
307 unsigned long size;
308 int ret;
310 if (!item)
311 return -1;
312 if (item->object.parsed)
313 return 0;
314 buffer = read_sha1_file(item->object.sha1, &type, &size);
315 if (!buffer)
316 return error("Could not read %s",
317 sha1_to_hex(item->object.sha1));
318 if (type != OBJ_COMMIT) {
319 free(buffer);
320 return error("Object %s not a commit",
321 sha1_to_hex(item->object.sha1));
323 ret = parse_commit_buffer(item, buffer, size);
324 if (save_commit_buffer && !ret) {
325 item->buffer = buffer;
326 return 0;
328 free(buffer);
329 return ret;
332 int find_commit_subject(const char *commit_buffer, const char **subject)
334 const char *eol;
335 const char *p = commit_buffer;
337 while (*p && (*p != '\n' || p[1] != '\n'))
338 p++;
339 if (*p) {
340 p += 2;
341 for (eol = p; *eol && *eol != '\n'; eol++)
342 ; /* do nothing */
343 } else
344 eol = p;
346 *subject = p;
348 return eol - p;
351 struct commit_list *commit_list_insert(struct commit *item, struct commit_list **list_p)
353 struct commit_list *new_list = xmalloc(sizeof(struct commit_list));
354 new_list->item = item;
355 new_list->next = *list_p;
356 *list_p = new_list;
357 return new_list;
360 unsigned commit_list_count(const struct commit_list *l)
362 unsigned c = 0;
363 for (; l; l = l->next )
364 c++;
365 return c;
368 void free_commit_list(struct commit_list *list)
370 while (list) {
371 struct commit_list *temp = list;
372 list = temp->next;
373 free(temp);
377 struct commit_list * commit_list_insert_by_date(struct commit *item, struct commit_list **list)
379 struct commit_list **pp = list;
380 struct commit_list *p;
381 while ((p = *pp) != NULL) {
382 if (p->item->date < item->date) {
383 break;
385 pp = &p->next;
387 return commit_list_insert(item, pp);
391 void commit_list_sort_by_date(struct commit_list **list)
393 struct commit_list *ret = NULL;
394 while (*list) {
395 commit_list_insert_by_date((*list)->item, &ret);
396 *list = (*list)->next;
398 *list = ret;
401 struct commit *pop_most_recent_commit(struct commit_list **list,
402 unsigned int mark)
404 struct commit *ret = (*list)->item;
405 struct commit_list *parents = ret->parents;
406 struct commit_list *old = *list;
408 *list = (*list)->next;
409 free(old);
411 while (parents) {
412 struct commit *commit = parents->item;
413 if (!parse_commit(commit) && !(commit->object.flags & mark)) {
414 commit->object.flags |= mark;
415 commit_list_insert_by_date(commit, list);
417 parents = parents->next;
419 return ret;
422 void clear_commit_marks(struct commit *commit, unsigned int mark)
424 while (commit) {
425 struct commit_list *parents;
427 if (!(mark & commit->object.flags))
428 return;
430 commit->object.flags &= ~mark;
432 parents = commit->parents;
433 if (!parents)
434 return;
436 while ((parents = parents->next))
437 clear_commit_marks(parents->item, mark);
439 commit = commit->parents->item;
443 struct commit *pop_commit(struct commit_list **stack)
445 struct commit_list *top = *stack;
446 struct commit *item = top ? top->item : NULL;
448 if (top) {
449 *stack = top->next;
450 free(top);
452 return item;
456 * Performs an in-place topological sort on the list supplied.
458 void sort_in_topological_order(struct commit_list ** list, int lifo)
460 struct commit_list *next, *orig = *list;
461 struct commit_list *work, **insert;
462 struct commit_list **pptr;
464 if (!orig)
465 return;
466 *list = NULL;
468 /* Mark them and clear the indegree */
469 for (next = orig; next; next = next->next) {
470 struct commit *commit = next->item;
471 commit->indegree = 1;
474 /* update the indegree */
475 for (next = orig; next; next = next->next) {
476 struct commit_list * parents = next->item->parents;
477 while (parents) {
478 struct commit *parent = parents->item;
480 if (parent->indegree)
481 parent->indegree++;
482 parents = parents->next;
487 * find the tips
489 * tips are nodes not reachable from any other node in the list
491 * the tips serve as a starting set for the work queue.
493 work = NULL;
494 insert = &work;
495 for (next = orig; next; next = next->next) {
496 struct commit *commit = next->item;
498 if (commit->indegree == 1)
499 insert = &commit_list_insert(commit, insert)->next;
502 /* process the list in topological order */
503 if (!lifo)
504 commit_list_sort_by_date(&work);
506 pptr = list;
507 *list = NULL;
508 while (work) {
509 struct commit *commit;
510 struct commit_list *parents, *work_item;
512 work_item = work;
513 work = work_item->next;
514 work_item->next = NULL;
516 commit = work_item->item;
517 for (parents = commit->parents; parents ; parents = parents->next) {
518 struct commit *parent=parents->item;
520 if (!parent->indegree)
521 continue;
524 * parents are only enqueued for emission
525 * when all their children have been emitted thereby
526 * guaranteeing topological order.
528 if (--parent->indegree == 1) {
529 if (!lifo)
530 commit_list_insert_by_date(parent, &work);
531 else
532 commit_list_insert(parent, &work);
536 * work_item is a commit all of whose children
537 * have already been emitted. we can emit it now.
539 commit->indegree = 0;
540 *pptr = work_item;
541 pptr = &work_item->next;
545 /* merge-base stuff */
547 /* bits #0..15 in revision.h */
548 #define PARENT1 (1u<<16)
549 #define PARENT2 (1u<<17)
550 #define STALE (1u<<18)
551 #define RESULT (1u<<19)
553 static const unsigned all_flags = (PARENT1 | PARENT2 | STALE | RESULT);
555 static struct commit *interesting(struct commit_list *list)
557 while (list) {
558 struct commit *commit = list->item;
559 list = list->next;
560 if (commit->object.flags & STALE)
561 continue;
562 return commit;
564 return NULL;
567 static struct commit_list *merge_bases_many(struct commit *one, int n, struct commit **twos)
569 struct commit_list *list = NULL;
570 struct commit_list *result = NULL;
571 int i;
573 for (i = 0; i < n; i++) {
574 if (one == twos[i])
576 * We do not mark this even with RESULT so we do not
577 * have to clean it up.
579 return commit_list_insert(one, &result);
582 if (parse_commit(one))
583 return NULL;
584 for (i = 0; i < n; i++) {
585 if (parse_commit(twos[i]))
586 return NULL;
589 one->object.flags |= PARENT1;
590 commit_list_insert_by_date(one, &list);
591 for (i = 0; i < n; i++) {
592 twos[i]->object.flags |= PARENT2;
593 commit_list_insert_by_date(twos[i], &list);
596 while (interesting(list)) {
597 struct commit *commit;
598 struct commit_list *parents;
599 struct commit_list *next;
600 int flags;
602 commit = list->item;
603 next = list->next;
604 free(list);
605 list = next;
607 flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
608 if (flags == (PARENT1 | PARENT2)) {
609 if (!(commit->object.flags & RESULT)) {
610 commit->object.flags |= RESULT;
611 commit_list_insert_by_date(commit, &result);
613 /* Mark parents of a found merge stale */
614 flags |= STALE;
616 parents = commit->parents;
617 while (parents) {
618 struct commit *p = parents->item;
619 parents = parents->next;
620 if ((p->object.flags & flags) == flags)
621 continue;
622 if (parse_commit(p))
623 return NULL;
624 p->object.flags |= flags;
625 commit_list_insert_by_date(p, &list);
629 /* Clean up the result to remove stale ones */
630 free_commit_list(list);
631 list = result; result = NULL;
632 while (list) {
633 struct commit_list *next = list->next;
634 if (!(list->item->object.flags & STALE))
635 commit_list_insert_by_date(list->item, &result);
636 free(list);
637 list = next;
639 return result;
642 struct commit_list *get_octopus_merge_bases(struct commit_list *in)
644 struct commit_list *i, *j, *k, *ret = NULL;
645 struct commit_list **pptr = &ret;
647 for (i = in; i; i = i->next) {
648 if (!ret)
649 pptr = &commit_list_insert(i->item, pptr)->next;
650 else {
651 struct commit_list *new = NULL, *end = NULL;
653 for (j = ret; j; j = j->next) {
654 struct commit_list *bases;
655 bases = get_merge_bases(i->item, j->item, 1);
656 if (!new)
657 new = bases;
658 else
659 end->next = bases;
660 for (k = bases; k; k = k->next)
661 end = k;
663 ret = new;
666 return ret;
669 struct commit_list *get_merge_bases_many(struct commit *one,
670 int n,
671 struct commit **twos,
672 int cleanup)
674 struct commit_list *list;
675 struct commit **rslt;
676 struct commit_list *result;
677 int cnt, i, j;
679 result = merge_bases_many(one, n, twos);
680 for (i = 0; i < n; i++) {
681 if (one == twos[i])
682 return result;
684 if (!result || !result->next) {
685 if (cleanup) {
686 clear_commit_marks(one, all_flags);
687 for (i = 0; i < n; i++)
688 clear_commit_marks(twos[i], all_flags);
690 return result;
693 /* There are more than one */
694 cnt = 0;
695 list = result;
696 while (list) {
697 list = list->next;
698 cnt++;
700 rslt = xcalloc(cnt, sizeof(*rslt));
701 for (list = result, i = 0; list; list = list->next)
702 rslt[i++] = list->item;
703 free_commit_list(result);
705 clear_commit_marks(one, all_flags);
706 for (i = 0; i < n; i++)
707 clear_commit_marks(twos[i], all_flags);
708 for (i = 0; i < cnt - 1; i++) {
709 for (j = i+1; j < cnt; j++) {
710 if (!rslt[i] || !rslt[j])
711 continue;
712 result = merge_bases_many(rslt[i], 1, &rslt[j]);
713 clear_commit_marks(rslt[i], all_flags);
714 clear_commit_marks(rslt[j], all_flags);
715 for (list = result; list; list = list->next) {
716 if (rslt[i] == list->item)
717 rslt[i] = NULL;
718 if (rslt[j] == list->item)
719 rslt[j] = NULL;
724 /* Surviving ones in rslt[] are the independent results */
725 result = NULL;
726 for (i = 0; i < cnt; i++) {
727 if (rslt[i])
728 commit_list_insert_by_date(rslt[i], &result);
730 free(rslt);
731 return result;
734 struct commit_list *get_merge_bases(struct commit *one, struct commit *two,
735 int cleanup)
737 return get_merge_bases_many(one, 1, &two, cleanup);
740 int is_descendant_of(struct commit *commit, struct commit_list *with_commit)
742 if (!with_commit)
743 return 1;
744 while (with_commit) {
745 struct commit *other;
747 other = with_commit->item;
748 with_commit = with_commit->next;
749 if (in_merge_bases(other, &commit, 1))
750 return 1;
752 return 0;
755 int in_merge_bases(struct commit *commit, struct commit **reference, int num)
757 struct commit_list *bases, *b;
758 int ret = 0;
760 if (num == 1)
761 bases = get_merge_bases(commit, *reference, 1);
762 else
763 die("not yet");
764 for (b = bases; b; b = b->next) {
765 if (!hashcmp(commit->object.sha1, b->item->object.sha1)) {
766 ret = 1;
767 break;
771 free_commit_list(bases);
772 return ret;
775 struct commit_list *reduce_heads(struct commit_list *heads)
777 struct commit_list *p;
778 struct commit_list *result = NULL, **tail = &result;
779 struct commit **other;
780 size_t num_head, num_other;
782 if (!heads)
783 return NULL;
785 /* Avoid unnecessary reallocations */
786 for (p = heads, num_head = 0; p; p = p->next)
787 num_head++;
788 other = xcalloc(sizeof(*other), num_head);
790 /* For each commit, see if it can be reached by others */
791 for (p = heads; p; p = p->next) {
792 struct commit_list *q, *base;
794 /* Do we already have this in the result? */
795 for (q = result; q; q = q->next)
796 if (p->item == q->item)
797 break;
798 if (q)
799 continue;
801 num_other = 0;
802 for (q = heads; q; q = q->next) {
803 if (p->item == q->item)
804 continue;
805 other[num_other++] = q->item;
807 if (num_other)
808 base = get_merge_bases_many(p->item, num_other, other, 1);
809 else
810 base = NULL;
812 * If p->item does not have anything common with other
813 * commits, there won't be any merge base. If it is
814 * reachable from some of the others, p->item will be
815 * the merge base. If its history is connected with
816 * others, but p->item is not reachable by others, we
817 * will get something other than p->item back.
819 if (!base || (base->item != p->item))
820 tail = &(commit_list_insert(p->item, tail)->next);
821 free_commit_list(base);
823 free(other);
824 return result;
827 static const char commit_utf8_warn[] =
828 "Warning: commit message does not conform to UTF-8.\n"
829 "You may want to amend it after fixing the message, or set the config\n"
830 "variable i18n.commitencoding to the encoding your project uses.\n";
832 int commit_tree(const char *msg, unsigned char *tree,
833 struct commit_list *parents, unsigned char *ret,
834 const char *author)
836 int result;
837 int encoding_is_utf8;
838 struct strbuf buffer;
840 assert_sha1_type(tree, OBJ_TREE);
842 /* Not having i18n.commitencoding is the same as having utf-8 */
843 encoding_is_utf8 = is_encoding_utf8(git_commit_encoding);
845 strbuf_init(&buffer, 8192); /* should avoid reallocs for the headers */
846 strbuf_addf(&buffer, "tree %s\n", sha1_to_hex(tree));
849 * NOTE! This ordering means that the same exact tree merged with a
850 * different order of parents will be a _different_ changeset even
851 * if everything else stays the same.
853 while (parents) {
854 struct commit_list *next = parents->next;
855 strbuf_addf(&buffer, "parent %s\n",
856 sha1_to_hex(parents->item->object.sha1));
857 free(parents);
858 parents = next;
861 /* Person/date information */
862 if (!author)
863 author = git_author_info(IDENT_ERROR_ON_NO_NAME);
864 strbuf_addf(&buffer, "author %s\n", author);
865 strbuf_addf(&buffer, "committer %s\n", git_committer_info(IDENT_ERROR_ON_NO_NAME));
866 if (!encoding_is_utf8)
867 strbuf_addf(&buffer, "encoding %s\n", git_commit_encoding);
868 strbuf_addch(&buffer, '\n');
870 /* And add the comment */
871 strbuf_addstr(&buffer, msg);
873 /* And check the encoding */
874 if (encoding_is_utf8 && !is_utf8(buffer.buf))
875 fprintf(stderr, commit_utf8_warn);
877 result = write_sha1_file(buffer.buf, buffer.len, commit_type, ret);
878 strbuf_release(&buffer);
879 return result;