ls-refs: filter refs using namespace-stripped name
[git/git.git] / commit.c
1 #include "cache.h"
2 #include "tag.h"
3 #include "commit.h"
4 #include "commit-graph.h"
5 #include "repository.h"
6 #include "object-store.h"
7 #include "pkt-line.h"
8 #include "utf8.h"
9 #include "diff.h"
10 #include "revision.h"
11 #include "notes.h"
12 #include "alloc.h"
13 #include "gpg-interface.h"
14 #include "mergesort.h"
15 #include "commit-slab.h"
16 #include "prio-queue.h"
17 #include "sha1-lookup.h"
18 #include "wt-status.h"
19 #include "advice.h"
20 #include "refs.h"
21 #include "commit-reach.h"
22
23 static struct commit_extra_header *read_commit_extra_header_lines(const char *buf, size_t len, const char **);
24
25 int save_commit_buffer = 1;
26
27 const char *commit_type = "commit";
28
29 struct commit *lookup_commit_reference_gently(struct repository *r,
30 const struct object_id *oid, int quiet)
31 {
32 struct object *obj = deref_tag(r,
33 parse_object(r, oid),
34 NULL, 0);
35
36 if (!obj)
37 return NULL;
38 return object_as_type(r, obj, OBJ_COMMIT, quiet);
39 }
40
41 struct commit *lookup_commit_reference(struct repository *r, const struct object_id *oid)
42 {
43 return lookup_commit_reference_gently(r, oid, 0);
44 }
45
46 struct commit *lookup_commit_or_die(const struct object_id *oid, const char *ref_name)
47 {
48 struct commit *c = lookup_commit_reference(the_repository, oid);
49 if (!c)
50 die(_("could not parse %s"), ref_name);
51 if (!oideq(oid, &c->object.oid)) {
52 warning(_("%s %s is not a commit!"),
53 ref_name, oid_to_hex(oid));
54 }
55 return c;
56 }
57
58 struct commit *lookup_commit(struct repository *r, const struct object_id *oid)
59 {
60 struct object *obj = lookup_object(r, oid->hash);
61 if (!obj)
62 return create_object(r, oid->hash,
63 alloc_commit_node(r));
64 return object_as_type(r, obj, OBJ_COMMIT, 0);
65 }
66
67 struct commit *lookup_commit_reference_by_name(const char *name)
68 {
69 struct object_id oid;
70 struct commit *commit;
71
72 if (get_oid_committish(name, &oid))
73 return NULL;
74 commit = lookup_commit_reference(the_repository, &oid);
75 if (parse_commit(commit))
76 return NULL;
77 return commit;
78 }
79
80 static timestamp_t parse_commit_date(const char *buf, const char *tail)
81 {
82 const char *dateptr;
83
84 if (buf + 6 >= tail)
85 return 0;
86 if (memcmp(buf, "author", 6))
87 return 0;
88 while (buf < tail && *buf++ != '\n')
89 /* nada */;
90 if (buf + 9 >= tail)
91 return 0;
92 if (memcmp(buf, "committer", 9))
93 return 0;
94 while (buf < tail && *buf++ != '>')
95 /* nada */;
96 if (buf >= tail)
97 return 0;
98 dateptr = buf;
99 while (buf < tail && *buf++ != '\n')
100 /* nada */;
101 if (buf >= tail)
102 return 0;
103 /* dateptr < buf && buf[-1] == '\n', so parsing will stop at buf-1 */
104 return parse_timestamp(dateptr, NULL, 10);
105 }
106
107 static const unsigned char *commit_graft_sha1_access(size_t index, void *table)
108 {
109 struct commit_graft **commit_graft_table = table;
110 return commit_graft_table[index]->oid.hash;
111 }
112
113 static int commit_graft_pos(struct repository *r, const unsigned char *sha1)
114 {
115 return sha1_pos(sha1, r->parsed_objects->grafts,
116 r->parsed_objects->grafts_nr,
117 commit_graft_sha1_access);
118 }
119
120 int register_commit_graft(struct repository *r, struct commit_graft *graft,
121 int ignore_dups)
122 {
123 int pos = commit_graft_pos(r, graft->oid.hash);
124
125 if (0 <= pos) {
126 if (ignore_dups)
127 free(graft);
128 else {
129 free(r->parsed_objects->grafts[pos]);
130 r->parsed_objects->grafts[pos] = graft;
131 }
132 return 1;
133 }
134 pos = -pos - 1;
135 ALLOC_GROW(r->parsed_objects->grafts,
136 r->parsed_objects->grafts_nr + 1,
137 r->parsed_objects->grafts_alloc);
138 r->parsed_objects->grafts_nr++;
139 if (pos < r->parsed_objects->grafts_nr)
140 memmove(r->parsed_objects->grafts + pos + 1,
141 r->parsed_objects->grafts + pos,
142 (r->parsed_objects->grafts_nr - pos - 1) *
143 sizeof(*r->parsed_objects->grafts));
144 r->parsed_objects->grafts[pos] = graft;
145 return 0;
146 }
147
148 struct commit_graft *read_graft_line(struct strbuf *line)
149 {
150 /* The format is just "Commit Parent1 Parent2 ...\n" */
151 int i, phase;
152 const char *tail = NULL;
153 struct commit_graft *graft = NULL;
154 struct object_id dummy_oid, *oid;
155
156 strbuf_rtrim(line);
157 if (!line->len || line->buf[0] == '#')
158 return NULL;
159 /*
160 * phase 0 verifies line, counts hashes in line and allocates graft
161 * phase 1 fills graft
162 */
163 for (phase = 0; phase < 2; phase++) {
164 oid = graft ? &graft->oid : &dummy_oid;
165 if (parse_oid_hex(line->buf, oid, &tail))
166 goto bad_graft_data;
167 for (i = 0; *tail != '\0'; i++) {
168 oid = graft ? &graft->parent[i] : &dummy_oid;
169 if (!isspace(*tail++) || parse_oid_hex(tail, oid, &tail))
170 goto bad_graft_data;
171 }
172 if (!graft) {
173 graft = xmalloc(st_add(sizeof(*graft),
174 st_mult(sizeof(struct object_id), i)));
175 graft->nr_parent = i;
176 }
177 }
178 return graft;
179
180 bad_graft_data:
181 error("bad graft data: %s", line->buf);
182 assert(!graft);
183 return NULL;
184 }
185
186 static int read_graft_file(struct repository *r, const char *graft_file)
187 {
188 FILE *fp = fopen_or_warn(graft_file, "r");
189 struct strbuf buf = STRBUF_INIT;
190 if (!fp)
191 return -1;
192 if (advice_graft_file_deprecated)
193 advise(_("Support for <GIT_DIR>/info/grafts is deprecated\n"
194 "and will be removed in a future Git version.\n"
195 "\n"
196 "Please use \"git replace --convert-graft-file\"\n"
197 "to convert the grafts into replace refs.\n"
198 "\n"
199 "Turn this message off by running\n"
200 "\"git config advice.graftFileDeprecated false\""));
201 while (!strbuf_getwholeline(&buf, fp, '\n')) {
202 /* The format is just "Commit Parent1 Parent2 ...\n" */
203 struct commit_graft *graft = read_graft_line(&buf);
204 if (!graft)
205 continue;
206 if (register_commit_graft(r, graft, 1))
207 error("duplicate graft data: %s", buf.buf);
208 }
209 fclose(fp);
210 strbuf_release(&buf);
211 return 0;
212 }
213
214 void prepare_commit_graft(struct repository *r)
215 {
216 char *graft_file;
217
218 if (r->parsed_objects->commit_graft_prepared)
219 return;
220 if (!startup_info->have_repository)
221 return;
222
223 graft_file = get_graft_file(r);
224 read_graft_file(r, graft_file);
225 /* make sure shallows are read */
226 is_repository_shallow(r);
227 r->parsed_objects->commit_graft_prepared = 1;
228 }
229
230 struct commit_graft *lookup_commit_graft(struct repository *r, const struct object_id *oid)
231 {
232 int pos;
233 prepare_commit_graft(r);
234 pos = commit_graft_pos(r, oid->hash);
235 if (pos < 0)
236 return NULL;
237 return r->parsed_objects->grafts[pos];
238 }
239
240 int for_each_commit_graft(each_commit_graft_fn fn, void *cb_data)
241 {
242 int i, ret;
243 for (i = ret = 0; i < the_repository->parsed_objects->grafts_nr && !ret; i++)
244 ret = fn(the_repository->parsed_objects->grafts[i], cb_data);
245 return ret;
246 }
247
248 int unregister_shallow(const struct object_id *oid)
249 {
250 int pos = commit_graft_pos(the_repository, oid->hash);
251 if (pos < 0)
252 return -1;
253 if (pos + 1 < the_repository->parsed_objects->grafts_nr)
254 MOVE_ARRAY(the_repository->parsed_objects->grafts + pos,
255 the_repository->parsed_objects->grafts + pos + 1,
256 the_repository->parsed_objects->grafts_nr - pos - 1);
257 the_repository->parsed_objects->grafts_nr--;
258 return 0;
259 }
260
261 struct commit_buffer {
262 void *buffer;
263 unsigned long size;
264 };
265 define_commit_slab(buffer_slab, struct commit_buffer);
266
267 struct buffer_slab *allocate_commit_buffer_slab(void)
268 {
269 struct buffer_slab *bs = xmalloc(sizeof(*bs));
270 init_buffer_slab(bs);
271 return bs;
272 }
273
274 void free_commit_buffer_slab(struct buffer_slab *bs)
275 {
276 clear_buffer_slab(bs);
277 free(bs);
278 }
279
280 void set_commit_buffer(struct repository *r, struct commit *commit, void *buffer, unsigned long size)
281 {
282 struct commit_buffer *v = buffer_slab_at(
283 r->parsed_objects->buffer_slab, commit);
284 v->buffer = buffer;
285 v->size = size;
286 }
287
288 const void *get_cached_commit_buffer(struct repository *r, const struct commit *commit, unsigned long *sizep)
289 {
290 struct commit_buffer *v = buffer_slab_peek(
291 r->parsed_objects->buffer_slab, commit);
292 if (!v) {
293 if (sizep)
294 *sizep = 0;
295 return NULL;
296 }
297 if (sizep)
298 *sizep = v->size;
299 return v->buffer;
300 }
301
302 const void *get_commit_buffer(const struct commit *commit, unsigned long *sizep)
303 {
304 const void *ret = get_cached_commit_buffer(the_repository, commit, sizep);
305 if (!ret) {
306 enum object_type type;
307 unsigned long size;
308 ret = read_object_file(&commit->object.oid, &type, &size);
309 if (!ret)
310 die("cannot read commit object %s",
311 oid_to_hex(&commit->object.oid));
312 if (type != OBJ_COMMIT)
313 die("expected commit for %s, got %s",
314 oid_to_hex(&commit->object.oid), type_name(type));
315 if (sizep)
316 *sizep = size;
317 }
318 return ret;
319 }
320
321 void unuse_commit_buffer(const struct commit *commit, const void *buffer)
322 {
323 struct commit_buffer *v = buffer_slab_peek(
324 the_repository->parsed_objects->buffer_slab, commit);
325 if (!(v && v->buffer == buffer))
326 free((void *)buffer);
327 }
328
329 void free_commit_buffer(struct commit *commit)
330 {
331 struct commit_buffer *v = buffer_slab_peek(
332 the_repository->parsed_objects->buffer_slab, commit);
333 if (v) {
334 FREE_AND_NULL(v->buffer);
335 v->size = 0;
336 }
337 }
338
339 struct tree *get_commit_tree(const struct commit *commit)
340 {
341 if (commit->maybe_tree || !commit->object.parsed)
342 return commit->maybe_tree;
343
344 if (commit->graph_pos == COMMIT_NOT_FROM_GRAPH)
345 BUG("commit has NULL tree, but was not loaded from commit-graph");
346
347 return get_commit_tree_in_graph(the_repository, commit);
348 }
349
350 struct object_id *get_commit_tree_oid(const struct commit *commit)
351 {
352 return &get_commit_tree(commit)->object.oid;
353 }
354
355 void release_commit_memory(struct commit *c)
356 {
357 c->maybe_tree = NULL;
358 c->index = 0;
359 free_commit_buffer(c);
360 free_commit_list(c->parents);
361 /* TODO: what about commit->util? */
362
363 c->object.parsed = 0;
364 }
365
366 const void *detach_commit_buffer(struct commit *commit, unsigned long *sizep)
367 {
368 struct commit_buffer *v = buffer_slab_peek(
369 the_repository->parsed_objects->buffer_slab, commit);
370 void *ret;
371
372 if (!v) {
373 if (sizep)
374 *sizep = 0;
375 return NULL;
376 }
377 ret = v->buffer;
378 if (sizep)
379 *sizep = v->size;
380
381 v->buffer = NULL;
382 v->size = 0;
383 return ret;
384 }
385
386 int parse_commit_buffer(struct repository *r, struct commit *item, const void *buffer, unsigned long size, int check_graph)
387 {
388 const char *tail = buffer;
389 const char *bufptr = buffer;
390 struct object_id parent;
391 struct commit_list **pptr;
392 struct commit_graft *graft;
393 const int tree_entry_len = the_hash_algo->hexsz + 5;
394 const int parent_entry_len = the_hash_algo->hexsz + 7;
395
396 if (item->object.parsed)
397 return 0;
398 item->object.parsed = 1;
399 tail += size;
400 if (tail <= bufptr + tree_entry_len + 1 || memcmp(bufptr, "tree ", 5) ||
401 bufptr[tree_entry_len] != '\n')
402 return error("bogus commit object %s", oid_to_hex(&item->object.oid));
403 if (get_oid_hex(bufptr + 5, &parent) < 0)
404 return error("bad tree pointer in commit %s",
405 oid_to_hex(&item->object.oid));
406 item->maybe_tree = lookup_tree(r, &parent);
407 bufptr += tree_entry_len + 1; /* "tree " + "hex sha1" + "\n" */
408 pptr = &item->parents;
409
410 graft = lookup_commit_graft(r, &item->object.oid);
411 while (bufptr + parent_entry_len < tail && !memcmp(bufptr, "parent ", 7)) {
412 struct commit *new_parent;
413
414 if (tail <= bufptr + parent_entry_len + 1 ||
415 get_oid_hex(bufptr + 7, &parent) ||
416 bufptr[parent_entry_len] != '\n')
417 return error("bad parents in commit %s", oid_to_hex(&item->object.oid));
418 bufptr += parent_entry_len + 1;
419 /*
420 * The clone is shallow if nr_parent < 0, and we must
421 * not traverse its real parents even when we unhide them.
422 */
423 if (graft && (graft->nr_parent < 0 || grafts_replace_parents))
424 continue;
425 new_parent = lookup_commit(r, &parent);
426 if (new_parent)
427 pptr = &commit_list_insert(new_parent, pptr)->next;
428 }
429 if (graft) {
430 int i;
431 struct commit *new_parent;
432 for (i = 0; i < graft->nr_parent; i++) {
433 new_parent = lookup_commit(r,
434 &graft->parent[i]);
435 if (!new_parent)
436 continue;
437 pptr = &commit_list_insert(new_parent, pptr)->next;
438 }
439 }
440 item->date = parse_commit_date(bufptr, tail);
441
442 if (check_graph)
443 load_commit_graph_info(the_repository, item);
444
445 return 0;
446 }
447
448 int parse_commit_internal(struct commit *item, int quiet_on_missing, int use_commit_graph)
449 {
450 enum object_type type;
451 void *buffer;
452 unsigned long size;
453 int ret;
454
455 if (!item)
456 return -1;
457 if (item->object.parsed)
458 return 0;
459 if (use_commit_graph && parse_commit_in_graph(the_repository, item))
460 return 0;
461 buffer = read_object_file(&item->object.oid, &type, &size);
462 if (!buffer)
463 return quiet_on_missing ? -1 :
464 error("Could not read %s",
465 oid_to_hex(&item->object.oid));
466 if (type != OBJ_COMMIT) {
467 free(buffer);
468 return error("Object %s not a commit",
469 oid_to_hex(&item->object.oid));
470 }
471
472 ret = parse_commit_buffer(the_repository, item, buffer, size, 0);
473 if (save_commit_buffer && !ret) {
474 set_commit_buffer(the_repository, item, buffer, size);
475 return 0;
476 }
477 free(buffer);
478 return ret;
479 }
480
481 int parse_commit_gently(struct commit *item, int quiet_on_missing)
482 {
483 return parse_commit_internal(item, quiet_on_missing, 1);
484 }
485
486 void parse_commit_or_die(struct commit *item)
487 {
488 if (parse_commit(item))
489 die("unable to parse commit %s",
490 item ? oid_to_hex(&item->object.oid) : "(null)");
491 }
492
493 int find_commit_subject(const char *commit_buffer, const char **subject)
494 {
495 const char *eol;
496 const char *p = commit_buffer;
497
498 while (*p && (*p != '\n' || p[1] != '\n'))
499 p++;
500 if (*p) {
501 p = skip_blank_lines(p + 2);
502 eol = strchrnul(p, '\n');
503 } else
504 eol = p;
505
506 *subject = p;
507
508 return eol - p;
509 }
510
511 struct commit_list *commit_list_insert(struct commit *item, struct commit_list **list_p)
512 {
513 struct commit_list *new_list = xmalloc(sizeof(struct commit_list));
514 new_list->item = item;
515 new_list->next = *list_p;
516 *list_p = new_list;
517 return new_list;
518 }
519
520 unsigned commit_list_count(const struct commit_list *l)
521 {
522 unsigned c = 0;
523 for (; l; l = l->next )
524 c++;
525 return c;
526 }
527
528 struct commit_list *copy_commit_list(struct commit_list *list)
529 {
530 struct commit_list *head = NULL;
531 struct commit_list **pp = &head;
532 while (list) {
533 pp = commit_list_append(list->item, pp);
534 list = list->next;
535 }
536 return head;
537 }
538
539 void free_commit_list(struct commit_list *list)
540 {
541 while (list)
542 pop_commit(&list);
543 }
544
545 struct commit_list * commit_list_insert_by_date(struct commit *item, struct commit_list **list)
546 {
547 struct commit_list **pp = list;
548 struct commit_list *p;
549 while ((p = *pp) != NULL) {
550 if (p->item->date < item->date) {
551 break;
552 }
553 pp = &p->next;
554 }
555 return commit_list_insert(item, pp);
556 }
557
558 static int commit_list_compare_by_date(const void *a, const void *b)
559 {
560 timestamp_t a_date = ((const struct commit_list *)a)->item->date;
561 timestamp_t b_date = ((const struct commit_list *)b)->item->date;
562 if (a_date < b_date)
563 return 1;
564 if (a_date > b_date)
565 return -1;
566 return 0;
567 }
568
569 static void *commit_list_get_next(const void *a)
570 {
571 return ((const struct commit_list *)a)->next;
572 }
573
574 static void commit_list_set_next(void *a, void *next)
575 {
576 ((struct commit_list *)a)->next = next;
577 }
578
579 void commit_list_sort_by_date(struct commit_list **list)
580 {
581 *list = llist_mergesort(*list, commit_list_get_next, commit_list_set_next,
582 commit_list_compare_by_date);
583 }
584
585 struct commit *pop_most_recent_commit(struct commit_list **list,
586 unsigned int mark)
587 {
588 struct commit *ret = pop_commit(list);
589 struct commit_list *parents = ret->parents;
590
591 while (parents) {
592 struct commit *commit = parents->item;
593 if (!parse_commit(commit) && !(commit->object.flags & mark)) {
594 commit->object.flags |= mark;
595 commit_list_insert_by_date(commit, list);
596 }
597 parents = parents->next;
598 }
599 return ret;
600 }
601
602 static void clear_commit_marks_1(struct commit_list **plist,
603 struct commit *commit, unsigned int mark)
604 {
605 while (commit) {
606 struct commit_list *parents;
607
608 if (!(mark & commit->object.flags))
609 return;
610
611 commit->object.flags &= ~mark;
612
613 parents = commit->parents;
614 if (!parents)
615 return;
616
617 while ((parents = parents->next))
618 commit_list_insert(parents->item, plist);
619
620 commit = commit->parents->item;
621 }
622 }
623
624 void clear_commit_marks_many(int nr, struct commit **commit, unsigned int mark)
625 {
626 struct commit_list *list = NULL;
627
628 while (nr--) {
629 clear_commit_marks_1(&list, *commit, mark);
630 commit++;
631 }
632 while (list)
633 clear_commit_marks_1(&list, pop_commit(&list), mark);
634 }
635
636 void clear_commit_marks(struct commit *commit, unsigned int mark)
637 {
638 clear_commit_marks_many(1, &commit, mark);
639 }
640
641 struct commit *pop_commit(struct commit_list **stack)
642 {
643 struct commit_list *top = *stack;
644 struct commit *item = top ? top->item : NULL;
645
646 if (top) {
647 *stack = top->next;
648 free(top);
649 }
650 return item;
651 }
652
653 /*
654 * Topological sort support
655 */
656
657 /* count number of children that have not been emitted */
658 define_commit_slab(indegree_slab, int);
659
660 define_commit_slab(author_date_slab, timestamp_t);
661
662 void record_author_date(struct author_date_slab *author_date,
663 struct commit *commit)
664 {
665 const char *buffer = get_commit_buffer(commit, NULL);
666 struct ident_split ident;
667 const char *ident_line;
668 size_t ident_len;
669 char *date_end;
670 timestamp_t date;
671
672 ident_line = find_commit_header(buffer, "author", &ident_len);
673 if (!ident_line)
674 goto fail_exit; /* no author line */
675 if (split_ident_line(&ident, ident_line, ident_len) ||
676 !ident.date_begin || !ident.date_end)
677 goto fail_exit; /* malformed "author" line */
678
679 date = parse_timestamp(ident.date_begin, &date_end, 10);
680 if (date_end != ident.date_end)
681 goto fail_exit; /* malformed date */
682 *(author_date_slab_at(author_date, commit)) = date;
683
684 fail_exit:
685 unuse_commit_buffer(commit, buffer);
686 }
687
688 int compare_commits_by_author_date(const void *a_, const void *b_,
689 void *cb_data)
690 {
691 const struct commit *a = a_, *b = b_;
692 struct author_date_slab *author_date = cb_data;
693 timestamp_t a_date = *(author_date_slab_at(author_date, a));
694 timestamp_t b_date = *(author_date_slab_at(author_date, b));
695
696 /* newer commits with larger date first */
697 if (a_date < b_date)
698 return 1;
699 else if (a_date > b_date)
700 return -1;
701 return 0;
702 }
703
704 int compare_commits_by_gen_then_commit_date(const void *a_, const void *b_, void *unused)
705 {
706 const struct commit *a = a_, *b = b_;
707
708 /* newer commits first */
709 if (a->generation < b->generation)
710 return 1;
711 else if (a->generation > b->generation)
712 return -1;
713
714 /* use date as a heuristic when generations are equal */
715 if (a->date < b->date)
716 return 1;
717 else if (a->date > b->date)
718 return -1;
719 return 0;
720 }
721
722 int compare_commits_by_commit_date(const void *a_, const void *b_, void *unused)
723 {
724 const struct commit *a = a_, *b = b_;
725 /* newer commits with larger date first */
726 if (a->date < b->date)
727 return 1;
728 else if (a->date > b->date)
729 return -1;
730 return 0;
731 }
732
733 /*
734 * Performs an in-place topological sort on the list supplied.
735 */
736 void sort_in_topological_order(struct commit_list **list, enum rev_sort_order sort_order)
737 {
738 struct commit_list *next, *orig = *list;
739 struct commit_list **pptr;
740 struct indegree_slab indegree;
741 struct prio_queue queue;
742 struct commit *commit;
743 struct author_date_slab author_date;
744
745 if (!orig)
746 return;
747 *list = NULL;
748
749 init_indegree_slab(&indegree);
750 memset(&queue, '\0', sizeof(queue));
751
752 switch (sort_order) {
753 default: /* REV_SORT_IN_GRAPH_ORDER */
754 queue.compare = NULL;
755 break;
756 case REV_SORT_BY_COMMIT_DATE:
757 queue.compare = compare_commits_by_commit_date;
758 break;
759 case REV_SORT_BY_AUTHOR_DATE:
760 init_author_date_slab(&author_date);
761 queue.compare = compare_commits_by_author_date;
762 queue.cb_data = &author_date;
763 break;
764 }
765
766 /* Mark them and clear the indegree */
767 for (next = orig; next; next = next->next) {
768 struct commit *commit = next->item;
769 *(indegree_slab_at(&indegree, commit)) = 1;
770 /* also record the author dates, if needed */
771 if (sort_order == REV_SORT_BY_AUTHOR_DATE)
772 record_author_date(&author_date, commit);
773 }
774
775 /* update the indegree */
776 for (next = orig; next; next = next->next) {
777 struct commit_list *parents = next->item->parents;
778 while (parents) {
779 struct commit *parent = parents->item;
780 int *pi = indegree_slab_at(&indegree, parent);
781
782 if (*pi)
783 (*pi)++;
784 parents = parents->next;
785 }
786 }
787
788 /*
789 * find the tips
790 *
791 * tips are nodes not reachable from any other node in the list
792 *
793 * the tips serve as a starting set for the work queue.
794 */
795 for (next = orig; next; next = next->next) {
796 struct commit *commit = next->item;
797
798 if (*(indegree_slab_at(&indegree, commit)) == 1)
799 prio_queue_put(&queue, commit);
800 }
801
802 /*
803 * This is unfortunate; the initial tips need to be shown
804 * in the order given from the revision traversal machinery.
805 */
806 if (sort_order == REV_SORT_IN_GRAPH_ORDER)
807 prio_queue_reverse(&queue);
808
809 /* We no longer need the commit list */
810 free_commit_list(orig);
811
812 pptr = list;
813 *list = NULL;
814 while ((commit = prio_queue_get(&queue)) != NULL) {
815 struct commit_list *parents;
816
817 for (parents = commit->parents; parents ; parents = parents->next) {
818 struct commit *parent = parents->item;
819 int *pi = indegree_slab_at(&indegree, parent);
820
821 if (!*pi)
822 continue;
823
824 /*
825 * parents are only enqueued for emission
826 * when all their children have been emitted thereby
827 * guaranteeing topological order.
828 */
829 if (--(*pi) == 1)
830 prio_queue_put(&queue, parent);
831 }
832 /*
833 * all children of commit have already been
834 * emitted. we can emit it now.
835 */
836 *(indegree_slab_at(&indegree, commit)) = 0;
837
838 pptr = &commit_list_insert(commit, pptr)->next;
839 }
840
841 clear_indegree_slab(&indegree);
842 clear_prio_queue(&queue);
843 if (sort_order == REV_SORT_BY_AUTHOR_DATE)
844 clear_author_date_slab(&author_date);
845 }
846
847 struct rev_collect {
848 struct commit **commit;
849 int nr;
850 int alloc;
851 unsigned int initial : 1;
852 };
853
854 static void add_one_commit(struct object_id *oid, struct rev_collect *revs)
855 {
856 struct commit *commit;
857
858 if (is_null_oid(oid))
859 return;
860
861 commit = lookup_commit(the_repository, oid);
862 if (!commit ||
863 (commit->object.flags & TMP_MARK) ||
864 parse_commit(commit))
865 return;
866
867 ALLOC_GROW(revs->commit, revs->nr + 1, revs->alloc);
868 revs->commit[revs->nr++] = commit;
869 commit->object.flags |= TMP_MARK;
870 }
871
872 static int collect_one_reflog_ent(struct object_id *ooid, struct object_id *noid,
873 const char *ident, timestamp_t timestamp,
874 int tz, const char *message, void *cbdata)
875 {
876 struct rev_collect *revs = cbdata;
877
878 if (revs->initial) {
879 revs->initial = 0;
880 add_one_commit(ooid, revs);
881 }
882 add_one_commit(noid, revs);
883 return 0;
884 }
885
886 struct commit *get_fork_point(const char *refname, struct commit *commit)
887 {
888 struct object_id oid;
889 struct rev_collect revs;
890 struct commit_list *bases;
891 int i;
892 struct commit *ret = NULL;
893
894 memset(&revs, 0, sizeof(revs));
895 revs.initial = 1;
896 for_each_reflog_ent(refname, collect_one_reflog_ent, &revs);
897
898 if (!revs.nr && !get_oid(refname, &oid))
899 add_one_commit(&oid, &revs);
900
901 for (i = 0; i < revs.nr; i++)
902 revs.commit[i]->object.flags &= ~TMP_MARK;
903
904 bases = get_merge_bases_many(commit, revs.nr, revs.commit);
905
906 /*
907 * There should be one and only one merge base, when we found
908 * a common ancestor among reflog entries.
909 */
910 if (!bases || bases->next)
911 goto cleanup_return;
912
913 /* And the found one must be one of the reflog entries */
914 for (i = 0; i < revs.nr; i++)
915 if (&bases->item->object == &revs.commit[i]->object)
916 break; /* found */
917 if (revs.nr <= i)
918 goto cleanup_return;
919
920 ret = bases->item;
921
922 cleanup_return:
923 free_commit_list(bases);
924 return ret;
925 }
926
927 static const char gpg_sig_header[] = "gpgsig";
928 static const int gpg_sig_header_len = sizeof(gpg_sig_header) - 1;
929
930 static int do_sign_commit(struct strbuf *buf, const char *keyid)
931 {
932 struct strbuf sig = STRBUF_INIT;
933 int inspos, copypos;
934 const char *eoh;
935
936 /* find the end of the header */
937 eoh = strstr(buf->buf, "\n\n");
938 if (!eoh)
939 inspos = buf->len;
940 else
941 inspos = eoh - buf->buf + 1;
942
943 if (!keyid || !*keyid)
944 keyid = get_signing_key();
945 if (sign_buffer(buf, &sig, keyid)) {
946 strbuf_release(&sig);
947 return -1;
948 }
949
950 for (copypos = 0; sig.buf[copypos]; ) {
951 const char *bol = sig.buf + copypos;
952 const char *eol = strchrnul(bol, '\n');
953 int len = (eol - bol) + !!*eol;
954
955 if (!copypos) {
956 strbuf_insert(buf, inspos, gpg_sig_header, gpg_sig_header_len);
957 inspos += gpg_sig_header_len;
958 }
959 strbuf_insert(buf, inspos++, " ", 1);
960 strbuf_insert(buf, inspos, bol, len);
961 inspos += len;
962 copypos += len;
963 }
964 strbuf_release(&sig);
965 return 0;
966 }
967
968 int parse_signed_commit(const struct commit *commit,
969 struct strbuf *payload, struct strbuf *signature)
970 {
971
972 unsigned long size;
973 const char *buffer = get_commit_buffer(commit, &size);
974 int in_signature, saw_signature = -1;
975 const char *line, *tail;
976
977 line = buffer;
978 tail = buffer + size;
979 in_signature = 0;
980 saw_signature = 0;
981 while (line < tail) {
982 const char *sig = NULL;
983 const char *next = memchr(line, '\n', tail - line);
984
985 next = next ? next + 1 : tail;
986 if (in_signature && line[0] == ' ')
987 sig = line + 1;
988 else if (starts_with(line, gpg_sig_header) &&
989 line[gpg_sig_header_len] == ' ')
990 sig = line + gpg_sig_header_len + 1;
991 if (sig) {
992 strbuf_add(signature, sig, next - sig);
993 saw_signature = 1;
994 in_signature = 1;
995 } else {
996 if (*line == '\n')
997 /* dump the whole remainder of the buffer */
998 next = tail;
999 strbuf_add(payload, line, next - line);
1000 in_signature = 0;
1001 }
1002 line = next;
1003 }
1004 unuse_commit_buffer(commit, buffer);
1005 return saw_signature;
1006 }
1007
1008 int remove_signature(struct strbuf *buf)
1009 {
1010 const char *line = buf->buf;
1011 const char *tail = buf->buf + buf->len;
1012 int in_signature = 0;
1013 const char *sig_start = NULL;
1014 const char *sig_end = NULL;
1015
1016 while (line < tail) {
1017 const char *next = memchr(line, '\n', tail - line);
1018 next = next ? next + 1 : tail;
1019
1020 if (in_signature && line[0] == ' ')
1021 sig_end = next;
1022 else if (starts_with(line, gpg_sig_header) &&
1023 line[gpg_sig_header_len] == ' ') {
1024 sig_start = line;
1025 sig_end = next;
1026 in_signature = 1;
1027 } else {
1028 if (*line == '\n')
1029 /* dump the whole remainder of the buffer */
1030 next = tail;
1031 in_signature = 0;
1032 }
1033 line = next;
1034 }
1035
1036 if (sig_start)
1037 strbuf_remove(buf, sig_start - buf->buf, sig_end - sig_start);
1038
1039 return sig_start != NULL;
1040 }
1041
1042 static void handle_signed_tag(struct commit *parent, struct commit_extra_header ***tail)
1043 {
1044 struct merge_remote_desc *desc;
1045 struct commit_extra_header *mergetag;
1046 char *buf;
1047 unsigned long size, len;
1048 enum object_type type;
1049
1050 desc = merge_remote_util(parent);
1051 if (!desc || !desc->obj)
1052 return;
1053 buf = read_object_file(&desc->obj->oid, &type, &size);
1054 if (!buf || type != OBJ_TAG)
1055 goto free_return;
1056 len = parse_signature(buf, size);
1057 if (size == len)
1058 goto free_return;
1059 /*
1060 * We could verify this signature and either omit the tag when
1061 * it does not validate, but the integrator may not have the
1062 * public key of the signer of the tag he is merging, while a
1063 * later auditor may have it while auditing, so let's not run
1064 * verify-signed-buffer here for now...
1065 *
1066 * if (verify_signed_buffer(buf, len, buf + len, size - len, ...))
1067 * warn("warning: signed tag unverified.");
1068 */
1069 mergetag = xcalloc(1, sizeof(*mergetag));
1070 mergetag->key = xstrdup("mergetag");
1071 mergetag->value = buf;
1072 mergetag->len = size;
1073
1074 **tail = mergetag;
1075 *tail = &mergetag->next;
1076 return;
1077
1078 free_return:
1079 free(buf);
1080 }
1081
1082 int check_commit_signature(const struct commit *commit, struct signature_check *sigc)
1083 {
1084 struct strbuf payload = STRBUF_INIT;
1085 struct strbuf signature = STRBUF_INIT;
1086 int ret = 1;
1087
1088 sigc->result = 'N';
1089
1090 if (parse_signed_commit(commit, &payload, &signature) <= 0)
1091 goto out;
1092 ret = check_signature(payload.buf, payload.len, signature.buf,
1093 signature.len, sigc);
1094
1095 out:
1096 strbuf_release(&payload);
1097 strbuf_release(&signature);
1098
1099 return ret;
1100 }
1101
1102 void verify_merge_signature(struct commit *commit, int verbosity)
1103 {
1104 char hex[GIT_MAX_HEXSZ + 1];
1105 struct signature_check signature_check;
1106 memset(&signature_check, 0, sizeof(signature_check));
1107
1108 check_commit_signature(commit, &signature_check);
1109
1110 find_unique_abbrev_r(hex, &commit->object.oid, DEFAULT_ABBREV);
1111 switch (signature_check.result) {
1112 case 'G':
1113 break;
1114 case 'U':
1115 die(_("Commit %s has an untrusted GPG signature, "
1116 "allegedly by %s."), hex, signature_check.signer);
1117 case 'B':
1118 die(_("Commit %s has a bad GPG signature "
1119 "allegedly by %s."), hex, signature_check.signer);
1120 default: /* 'N' */
1121 die(_("Commit %s does not have a GPG signature."), hex);
1122 }
1123 if (verbosity >= 0 && signature_check.result == 'G')
1124 printf(_("Commit %s has a good GPG signature by %s\n"),
1125 hex, signature_check.signer);
1126
1127 signature_check_clear(&signature_check);
1128 }
1129
1130 void append_merge_tag_headers(struct commit_list *parents,
1131 struct commit_extra_header ***tail)
1132 {
1133 while (parents) {
1134 struct commit *parent = parents->item;
1135 handle_signed_tag(parent, tail);
1136 parents = parents->next;
1137 }
1138 }
1139
1140 static void add_extra_header(struct strbuf *buffer,
1141 struct commit_extra_header *extra)
1142 {
1143 strbuf_addstr(buffer, extra->key);
1144 if (extra->len)
1145 strbuf_add_lines(buffer, " ", extra->value, extra->len);
1146 else
1147 strbuf_addch(buffer, '\n');
1148 }
1149
1150 struct commit_extra_header *read_commit_extra_headers(struct commit *commit,
1151 const char **exclude)
1152 {
1153 struct commit_extra_header *extra = NULL;
1154 unsigned long size;
1155 const char *buffer = get_commit_buffer(commit, &size);
1156 extra = read_commit_extra_header_lines(buffer, size, exclude);
1157 unuse_commit_buffer(commit, buffer);
1158 return extra;
1159 }
1160
1161 int for_each_mergetag(each_mergetag_fn fn, struct commit *commit, void *data)
1162 {
1163 struct commit_extra_header *extra, *to_free;
1164 int res = 0;
1165
1166 to_free = read_commit_extra_headers(commit, NULL);
1167 for (extra = to_free; !res && extra; extra = extra->next) {
1168 if (strcmp(extra->key, "mergetag"))
1169 continue; /* not a merge tag */
1170 res = fn(commit, extra, data);
1171 }
1172 free_commit_extra_headers(to_free);
1173 return res;
1174 }
1175
1176 static inline int standard_header_field(const char *field, size_t len)
1177 {
1178 return ((len == 4 && !memcmp(field, "tree", 4)) ||
1179 (len == 6 && !memcmp(field, "parent", 6)) ||
1180 (len == 6 && !memcmp(field, "author", 6)) ||
1181 (len == 9 && !memcmp(field, "committer", 9)) ||
1182 (len == 8 && !memcmp(field, "encoding", 8)));
1183 }
1184
1185 static int excluded_header_field(const char *field, size_t len, const char **exclude)
1186 {
1187 if (!exclude)
1188 return 0;
1189
1190 while (*exclude) {
1191 size_t xlen = strlen(*exclude);
1192 if (len == xlen && !memcmp(field, *exclude, xlen))
1193 return 1;
1194 exclude++;
1195 }
1196 return 0;
1197 }
1198
1199 static struct commit_extra_header *read_commit_extra_header_lines(
1200 const char *buffer, size_t size,
1201 const char **exclude)
1202 {
1203 struct commit_extra_header *extra = NULL, **tail = &extra, *it = NULL;
1204 const char *line, *next, *eof, *eob;
1205 struct strbuf buf = STRBUF_INIT;
1206
1207 for (line = buffer, eob = line + size;
1208 line < eob && *line != '\n';
1209 line = next) {
1210 next = memchr(line, '\n', eob - line);
1211 next = next ? next + 1 : eob;
1212 if (*line == ' ') {
1213 /* continuation */
1214 if (it)
1215 strbuf_add(&buf, line + 1, next - (line + 1));
1216 continue;
1217 }
1218 if (it)
1219 it->value = strbuf_detach(&buf, &it->len);
1220 strbuf_reset(&buf);
1221 it = NULL;
1222
1223 eof = memchr(line, ' ', next - line);
1224 if (!eof)
1225 eof = next;
1226 else if (standard_header_field(line, eof - line) ||
1227 excluded_header_field(line, eof - line, exclude))
1228 continue;
1229
1230 it = xcalloc(1, sizeof(*it));
1231 it->key = xmemdupz(line, eof-line);
1232 *tail = it;
1233 tail = &it->next;
1234 if (eof + 1 < next)
1235 strbuf_add(&buf, eof + 1, next - (eof + 1));
1236 }
1237 if (it)
1238 it->value = strbuf_detach(&buf, &it->len);
1239 return extra;
1240 }
1241
1242 void free_commit_extra_headers(struct commit_extra_header *extra)
1243 {
1244 while (extra) {
1245 struct commit_extra_header *next = extra->next;
1246 free(extra->key);
1247 free(extra->value);
1248 free(extra);
1249 extra = next;
1250 }
1251 }
1252
1253 int commit_tree(const char *msg, size_t msg_len, const struct object_id *tree,
1254 struct commit_list *parents, struct object_id *ret,
1255 const char *author, const char *sign_commit)
1256 {
1257 struct commit_extra_header *extra = NULL, **tail = &extra;
1258 int result;
1259
1260 append_merge_tag_headers(parents, &tail);
1261 result = commit_tree_extended(msg, msg_len, tree, parents, ret,
1262 author, sign_commit, extra);
1263 free_commit_extra_headers(extra);
1264 return result;
1265 }
1266
1267 static int find_invalid_utf8(const char *buf, int len)
1268 {
1269 int offset = 0;
1270 static const unsigned int max_codepoint[] = {
1271 0x7f, 0x7ff, 0xffff, 0x10ffff
1272 };
1273
1274 while (len) {
1275 unsigned char c = *buf++;
1276 int bytes, bad_offset;
1277 unsigned int codepoint;
1278 unsigned int min_val, max_val;
1279
1280 len--;
1281 offset++;
1282
1283 /* Simple US-ASCII? No worries. */
1284 if (c < 0x80)
1285 continue;
1286
1287 bad_offset = offset-1;
1288
1289 /*
1290 * Count how many more high bits set: that's how
1291 * many more bytes this sequence should have.
1292 */
1293 bytes = 0;
1294 while (c & 0x40) {
1295 c <<= 1;
1296 bytes++;
1297 }
1298
1299 /*
1300 * Must be between 1 and 3 more bytes. Longer sequences result in
1301 * codepoints beyond U+10FFFF, which are guaranteed never to exist.
1302 */
1303 if (bytes < 1 || 3 < bytes)
1304 return bad_offset;
1305
1306 /* Do we *have* that many bytes? */
1307 if (len < bytes)
1308 return bad_offset;
1309
1310 /*
1311 * Place the encoded bits at the bottom of the value and compute the
1312 * valid range.
1313 */
1314 codepoint = (c & 0x7f) >> bytes;
1315 min_val = max_codepoint[bytes-1] + 1;
1316 max_val = max_codepoint[bytes];
1317
1318 offset += bytes;
1319 len -= bytes;
1320
1321 /* And verify that they are good continuation bytes */
1322 do {
1323 codepoint <<= 6;
1324 codepoint |= *buf & 0x3f;
1325 if ((*buf++ & 0xc0) != 0x80)
1326 return bad_offset;
1327 } while (--bytes);
1328
1329 /* Reject codepoints that are out of range for the sequence length. */
1330 if (codepoint < min_val || codepoint > max_val)
1331 return bad_offset;
1332 /* Surrogates are only for UTF-16 and cannot be encoded in UTF-8. */
1333 if ((codepoint & 0x1ff800) == 0xd800)
1334 return bad_offset;
1335 /* U+xxFFFE and U+xxFFFF are guaranteed non-characters. */
1336 if ((codepoint & 0xfffe) == 0xfffe)
1337 return bad_offset;
1338 /* So are anything in the range U+FDD0..U+FDEF. */
1339 if (codepoint >= 0xfdd0 && codepoint <= 0xfdef)
1340 return bad_offset;
1341 }
1342 return -1;
1343 }
1344
1345 /*
1346 * This verifies that the buffer is in proper utf8 format.
1347 *
1348 * If it isn't, it assumes any non-utf8 characters are Latin1,
1349 * and does the conversion.
1350 */
1351 static int verify_utf8(struct strbuf *buf)
1352 {
1353 int ok = 1;
1354 long pos = 0;
1355
1356 for (;;) {
1357 int bad;
1358 unsigned char c;
1359 unsigned char replace[2];
1360
1361 bad = find_invalid_utf8(buf->buf + pos, buf->len - pos);
1362 if (bad < 0)
1363 return ok;
1364 pos += bad;
1365 ok = 0;
1366 c = buf->buf[pos];
1367 strbuf_remove(buf, pos, 1);
1368
1369 /* We know 'c' must be in the range 128-255 */
1370 replace[0] = 0xc0 + (c >> 6);
1371 replace[1] = 0x80 + (c & 0x3f);
1372 strbuf_insert(buf, pos, replace, 2);
1373 pos += 2;
1374 }
1375 }
1376
1377 static const char commit_utf8_warn[] =
1378 N_("Warning: commit message did not conform to UTF-8.\n"
1379 "You may want to amend it after fixing the message, or set the config\n"
1380 "variable i18n.commitencoding to the encoding your project uses.\n");
1381
1382 int commit_tree_extended(const char *msg, size_t msg_len,
1383 const struct object_id *tree,
1384 struct commit_list *parents, struct object_id *ret,
1385 const char *author, const char *sign_commit,
1386 struct commit_extra_header *extra)
1387 {
1388 int result;
1389 int encoding_is_utf8;
1390 struct strbuf buffer;
1391
1392 assert_oid_type(tree, OBJ_TREE);
1393
1394 if (memchr(msg, '\0', msg_len))
1395 return error("a NUL byte in commit log message not allowed.");
1396
1397 /* Not having i18n.commitencoding is the same as having utf-8 */
1398 encoding_is_utf8 = is_encoding_utf8(git_commit_encoding);
1399
1400 strbuf_init(&buffer, 8192); /* should avoid reallocs for the headers */
1401 strbuf_addf(&buffer, "tree %s\n", oid_to_hex(tree));
1402
1403 /*
1404 * NOTE! This ordering means that the same exact tree merged with a
1405 * different order of parents will be a _different_ changeset even
1406 * if everything else stays the same.
1407 */
1408 while (parents) {
1409 struct commit *parent = pop_commit(&parents);
1410 strbuf_addf(&buffer, "parent %s\n",
1411 oid_to_hex(&parent->object.oid));
1412 }
1413
1414 /* Person/date information */
1415 if (!author)
1416 author = git_author_info(IDENT_STRICT);
1417 strbuf_addf(&buffer, "author %s\n", author);
1418 strbuf_addf(&buffer, "committer %s\n", git_committer_info(IDENT_STRICT));
1419 if (!encoding_is_utf8)
1420 strbuf_addf(&buffer, "encoding %s\n", git_commit_encoding);
1421
1422 while (extra) {
1423 add_extra_header(&buffer, extra);
1424 extra = extra->next;
1425 }
1426 strbuf_addch(&buffer, '\n');
1427
1428 /* And add the comment */
1429 strbuf_add(&buffer, msg, msg_len);
1430
1431 /* And check the encoding */
1432 if (encoding_is_utf8 && !verify_utf8(&buffer))
1433 fprintf(stderr, _(commit_utf8_warn));
1434
1435 if (sign_commit && do_sign_commit(&buffer, sign_commit)) {
1436 result = -1;
1437 goto out;
1438 }
1439
1440 result = write_object_file(buffer.buf, buffer.len, commit_type, ret);
1441 out:
1442 strbuf_release(&buffer);
1443 return result;
1444 }
1445
1446 define_commit_slab(merge_desc_slab, struct merge_remote_desc *);
1447 static struct merge_desc_slab merge_desc_slab = COMMIT_SLAB_INIT(1, merge_desc_slab);
1448
1449 struct merge_remote_desc *merge_remote_util(struct commit *commit)
1450 {
1451 return *merge_desc_slab_at(&merge_desc_slab, commit);
1452 }
1453
1454 void set_merge_remote_desc(struct commit *commit,
1455 const char *name, struct object *obj)
1456 {
1457 struct merge_remote_desc *desc;
1458 FLEX_ALLOC_STR(desc, name, name);
1459 desc->obj = obj;
1460 *merge_desc_slab_at(&merge_desc_slab, commit) = desc;
1461 }
1462
1463 struct commit *get_merge_parent(const char *name)
1464 {
1465 struct object *obj;
1466 struct commit *commit;
1467 struct object_id oid;
1468 if (get_oid(name, &oid))
1469 return NULL;
1470 obj = parse_object(the_repository, &oid);
1471 commit = (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
1472 if (commit && !merge_remote_util(commit))
1473 set_merge_remote_desc(commit, name, obj);
1474 return commit;
1475 }
1476
1477 /*
1478 * Append a commit to the end of the commit_list.
1479 *
1480 * next starts by pointing to the variable that holds the head of an
1481 * empty commit_list, and is updated to point to the "next" field of
1482 * the last item on the list as new commits are appended.
1483 *
1484 * Usage example:
1485 *
1486 * struct commit_list *list;
1487 * struct commit_list **next = &list;
1488 *
1489 * next = commit_list_append(c1, next);
1490 * next = commit_list_append(c2, next);
1491 * assert(commit_list_count(list) == 2);
1492 * return list;
1493 */
1494 struct commit_list **commit_list_append(struct commit *commit,
1495 struct commit_list **next)
1496 {
1497 struct commit_list *new_commit = xmalloc(sizeof(struct commit_list));
1498 new_commit->item = commit;
1499 *next = new_commit;
1500 new_commit->next = NULL;
1501 return &new_commit->next;
1502 }
1503
1504 const char *find_commit_header(const char *msg, const char *key, size_t *out_len)
1505 {
1506 int key_len = strlen(key);
1507 const char *line = msg;
1508
1509 while (line) {
1510 const char *eol = strchrnul(line, '\n');
1511
1512 if (line == eol)
1513 return NULL;
1514
1515 if (eol - line > key_len &&
1516 !strncmp(line, key, key_len) &&
1517 line[key_len] == ' ') {
1518 *out_len = eol - line - key_len - 1;
1519 return line + key_len + 1;
1520 }
1521 line = *eol ? eol + 1 : NULL;
1522 }
1523 return NULL;
1524 }
1525
1526 /*
1527 * Inspect the given string and determine the true "end" of the log message, in
1528 * order to find where to put a new Signed-off-by: line. Ignored are
1529 * trailing comment lines and blank lines. To support "git commit -s
1530 * --amend" on an existing commit, we also ignore "Conflicts:". To
1531 * support "git commit -v", we truncate at cut lines.
1532 *
1533 * Returns the number of bytes from the tail to ignore, to be fed as
1534 * the second parameter to append_signoff().
1535 */
1536 size_t ignore_non_trailer(const char *buf, size_t len)
1537 {
1538 size_t boc = 0;
1539 size_t bol = 0;
1540 int in_old_conflicts_block = 0;
1541 size_t cutoff = wt_status_locate_end(buf, len);
1542
1543 while (bol < cutoff) {
1544 const char *next_line = memchr(buf + bol, '\n', len - bol);
1545
1546 if (!next_line)
1547 next_line = buf + len;
1548 else
1549 next_line++;
1550
1551 if (buf[bol] == comment_line_char || buf[bol] == '\n') {
1552 /* is this the first of the run of comments? */
1553 if (!boc)
1554 boc = bol;
1555 /* otherwise, it is just continuing */
1556 } else if (starts_with(buf + bol, "Conflicts:\n")) {
1557 in_old_conflicts_block = 1;
1558 if (!boc)
1559 boc = bol;
1560 } else if (in_old_conflicts_block && buf[bol] == '\t') {
1561 ; /* a pathname in the conflicts block */
1562 } else if (boc) {
1563 /* the previous was not trailing comment */
1564 boc = 0;
1565 in_old_conflicts_block = 0;
1566 }
1567 bol = next_line - buf;
1568 }
1569 return boc ? len - boc : len - cutoff;
1570 }