Merge branch 'ds/commit-graph-with-grafts' into maint
[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
21 static struct commit_extra_header *read_commit_extra_header_lines(const char *buf, size_t len, const char **);
22
23 int save_commit_buffer = 1;
24
25 const char *commit_type = "commit";
26
27 struct commit *lookup_commit_reference_gently(struct repository *r,
28 const struct object_id *oid, int quiet)
29 {
30 struct object *obj = deref_tag(r,
31 parse_object(r, oid),
32 NULL, 0);
33
34 if (!obj)
35 return NULL;
36 return object_as_type(r, obj, OBJ_COMMIT, quiet);
37 }
38
39 struct commit *lookup_commit_reference(struct repository *r, const struct object_id *oid)
40 {
41 return lookup_commit_reference_gently(r, oid, 0);
42 }
43
44 struct commit *lookup_commit_or_die(const struct object_id *oid, const char *ref_name)
45 {
46 struct commit *c = lookup_commit_reference(the_repository, oid);
47 if (!c)
48 die(_("could not parse %s"), ref_name);
49 if (oidcmp(oid, &c->object.oid)) {
50 warning(_("%s %s is not a commit!"),
51 ref_name, oid_to_hex(oid));
52 }
53 return c;
54 }
55
56 struct commit *lookup_commit(struct repository *r, const struct object_id *oid)
57 {
58 struct object *obj = lookup_object(r, oid->hash);
59 if (!obj)
60 return create_object(r, oid->hash,
61 alloc_commit_node(r));
62 return object_as_type(r, obj, OBJ_COMMIT, 0);
63 }
64
65 struct commit *lookup_commit_reference_by_name(const char *name)
66 {
67 struct object_id oid;
68 struct commit *commit;
69
70 if (get_oid_committish(name, &oid))
71 return NULL;
72 commit = lookup_commit_reference(the_repository, &oid);
73 if (parse_commit(commit))
74 return NULL;
75 return commit;
76 }
77
78 static timestamp_t parse_commit_date(const char *buf, const char *tail)
79 {
80 const char *dateptr;
81
82 if (buf + 6 >= tail)
83 return 0;
84 if (memcmp(buf, "author", 6))
85 return 0;
86 while (buf < tail && *buf++ != '\n')
87 /* nada */;
88 if (buf + 9 >= tail)
89 return 0;
90 if (memcmp(buf, "committer", 9))
91 return 0;
92 while (buf < tail && *buf++ != '>')
93 /* nada */;
94 if (buf >= tail)
95 return 0;
96 dateptr = buf;
97 while (buf < tail && *buf++ != '\n')
98 /* nada */;
99 if (buf >= tail)
100 return 0;
101 /* dateptr < buf && buf[-1] == '\n', so parsing will stop at buf-1 */
102 return parse_timestamp(dateptr, NULL, 10);
103 }
104
105 static const unsigned char *commit_graft_sha1_access(size_t index, void *table)
106 {
107 struct commit_graft **commit_graft_table = table;
108 return commit_graft_table[index]->oid.hash;
109 }
110
111 static int commit_graft_pos(struct repository *r, const unsigned char *sha1)
112 {
113 return sha1_pos(sha1, r->parsed_objects->grafts,
114 r->parsed_objects->grafts_nr,
115 commit_graft_sha1_access);
116 }
117
118 int register_commit_graft(struct repository *r, struct commit_graft *graft,
119 int ignore_dups)
120 {
121 int pos = commit_graft_pos(r, graft->oid.hash);
122
123 if (0 <= pos) {
124 if (ignore_dups)
125 free(graft);
126 else {
127 free(r->parsed_objects->grafts[pos]);
128 r->parsed_objects->grafts[pos] = graft;
129 }
130 return 1;
131 }
132 pos = -pos - 1;
133 ALLOC_GROW(r->parsed_objects->grafts,
134 r->parsed_objects->grafts_nr + 1,
135 r->parsed_objects->grafts_alloc);
136 r->parsed_objects->grafts_nr++;
137 if (pos < r->parsed_objects->grafts_nr)
138 memmove(r->parsed_objects->grafts + pos + 1,
139 r->parsed_objects->grafts + pos,
140 (r->parsed_objects->grafts_nr - pos - 1) *
141 sizeof(*r->parsed_objects->grafts));
142 r->parsed_objects->grafts[pos] = graft;
143 return 0;
144 }
145
146 struct commit_graft *read_graft_line(struct strbuf *line)
147 {
148 /* The format is just "Commit Parent1 Parent2 ...\n" */
149 int i, phase;
150 const char *tail = NULL;
151 struct commit_graft *graft = NULL;
152 struct object_id dummy_oid, *oid;
153
154 strbuf_rtrim(line);
155 if (!line->len || line->buf[0] == '#')
156 return NULL;
157 /*
158 * phase 0 verifies line, counts hashes in line and allocates graft
159 * phase 1 fills graft
160 */
161 for (phase = 0; phase < 2; phase++) {
162 oid = graft ? &graft->oid : &dummy_oid;
163 if (parse_oid_hex(line->buf, oid, &tail))
164 goto bad_graft_data;
165 for (i = 0; *tail != '\0'; i++) {
166 oid = graft ? &graft->parent[i] : &dummy_oid;
167 if (!isspace(*tail++) || parse_oid_hex(tail, oid, &tail))
168 goto bad_graft_data;
169 }
170 if (!graft) {
171 graft = xmalloc(st_add(sizeof(*graft),
172 st_mult(sizeof(struct object_id), i)));
173 graft->nr_parent = i;
174 }
175 }
176 return graft;
177
178 bad_graft_data:
179 error("bad graft data: %s", line->buf);
180 assert(!graft);
181 return NULL;
182 }
183
184 static int read_graft_file(struct repository *r, const char *graft_file)
185 {
186 FILE *fp = fopen_or_warn(graft_file, "r");
187 struct strbuf buf = STRBUF_INIT;
188 if (!fp)
189 return -1;
190 if (advice_graft_file_deprecated)
191 advise(_("Support for <GIT_DIR>/info/grafts is deprecated\n"
192 "and will be removed in a future Git version.\n"
193 "\n"
194 "Please use \"git replace --convert-graft-file\"\n"
195 "to convert the grafts into replace refs.\n"
196 "\n"
197 "Turn this message off by running\n"
198 "\"git config advice.graftFileDeprecated false\""));
199 while (!strbuf_getwholeline(&buf, fp, '\n')) {
200 /* The format is just "Commit Parent1 Parent2 ...\n" */
201 struct commit_graft *graft = read_graft_line(&buf);
202 if (!graft)
203 continue;
204 if (register_commit_graft(r, graft, 1))
205 error("duplicate graft data: %s", buf.buf);
206 }
207 fclose(fp);
208 strbuf_release(&buf);
209 return 0;
210 }
211
212 void prepare_commit_graft(struct repository *r)
213 {
214 char *graft_file;
215
216 if (r->parsed_objects->commit_graft_prepared)
217 return;
218 if (!startup_info->have_repository)
219 return;
220
221 graft_file = get_graft_file(r);
222 read_graft_file(r, graft_file);
223 /* make sure shallows are read */
224 is_repository_shallow(r);
225 r->parsed_objects->commit_graft_prepared = 1;
226 }
227
228 struct commit_graft *lookup_commit_graft(struct repository *r, const struct object_id *oid)
229 {
230 int pos;
231 prepare_commit_graft(r);
232 pos = commit_graft_pos(r, oid->hash);
233 if (pos < 0)
234 return NULL;
235 return r->parsed_objects->grafts[pos];
236 }
237
238 int for_each_commit_graft(each_commit_graft_fn fn, void *cb_data)
239 {
240 int i, ret;
241 for (i = ret = 0; i < the_repository->parsed_objects->grafts_nr && !ret; i++)
242 ret = fn(the_repository->parsed_objects->grafts[i], cb_data);
243 return ret;
244 }
245
246 int unregister_shallow(const struct object_id *oid)
247 {
248 int pos = commit_graft_pos(the_repository, oid->hash);
249 if (pos < 0)
250 return -1;
251 if (pos + 1 < the_repository->parsed_objects->grafts_nr)
252 MOVE_ARRAY(the_repository->parsed_objects->grafts + pos,
253 the_repository->parsed_objects->grafts + pos + 1,
254 the_repository->parsed_objects->grafts_nr - pos - 1);
255 the_repository->parsed_objects->grafts_nr--;
256 return 0;
257 }
258
259 struct commit_buffer {
260 void *buffer;
261 unsigned long size;
262 };
263 define_commit_slab(buffer_slab, struct commit_buffer);
264
265 struct buffer_slab *allocate_commit_buffer_slab(void)
266 {
267 struct buffer_slab *bs = xmalloc(sizeof(*bs));
268 init_buffer_slab(bs);
269 return bs;
270 }
271
272 void free_commit_buffer_slab(struct buffer_slab *bs)
273 {
274 clear_buffer_slab(bs);
275 free(bs);
276 }
277
278 void set_commit_buffer(struct repository *r, struct commit *commit, void *buffer, unsigned long size)
279 {
280 struct commit_buffer *v = buffer_slab_at(
281 r->parsed_objects->buffer_slab, commit);
282 v->buffer = buffer;
283 v->size = size;
284 }
285
286 const void *get_cached_commit_buffer(struct repository *r, const struct commit *commit, unsigned long *sizep)
287 {
288 struct commit_buffer *v = buffer_slab_peek(
289 r->parsed_objects->buffer_slab, commit);
290 if (!v) {
291 if (sizep)
292 *sizep = 0;
293 return NULL;
294 }
295 if (sizep)
296 *sizep = v->size;
297 return v->buffer;
298 }
299
300 const void *get_commit_buffer(const struct commit *commit, unsigned long *sizep)
301 {
302 const void *ret = get_cached_commit_buffer(the_repository, commit, sizep);
303 if (!ret) {
304 enum object_type type;
305 unsigned long size;
306 ret = read_object_file(&commit->object.oid, &type, &size);
307 if (!ret)
308 die("cannot read commit object %s",
309 oid_to_hex(&commit->object.oid));
310 if (type != OBJ_COMMIT)
311 die("expected commit for %s, got %s",
312 oid_to_hex(&commit->object.oid), type_name(type));
313 if (sizep)
314 *sizep = size;
315 }
316 return ret;
317 }
318
319 void unuse_commit_buffer(const struct commit *commit, const void *buffer)
320 {
321 struct commit_buffer *v = buffer_slab_peek(
322 the_repository->parsed_objects->buffer_slab, commit);
323 if (!(v && v->buffer == buffer))
324 free((void *)buffer);
325 }
326
327 void free_commit_buffer(struct commit *commit)
328 {
329 struct commit_buffer *v = buffer_slab_peek(
330 the_repository->parsed_objects->buffer_slab, commit);
331 if (v) {
332 FREE_AND_NULL(v->buffer);
333 v->size = 0;
334 }
335 }
336
337 struct tree *get_commit_tree(const struct commit *commit)
338 {
339 if (commit->maybe_tree || !commit->object.parsed)
340 return commit->maybe_tree;
341
342 if (commit->graph_pos == COMMIT_NOT_FROM_GRAPH)
343 BUG("commit has NULL tree, but was not loaded from commit-graph");
344
345 return get_commit_tree_in_graph(the_repository, commit);
346 }
347
348 struct object_id *get_commit_tree_oid(const struct commit *commit)
349 {
350 return &get_commit_tree(commit)->object.oid;
351 }
352
353 void release_commit_memory(struct commit *c)
354 {
355 c->maybe_tree = NULL;
356 c->index = 0;
357 free_commit_buffer(c);
358 free_commit_list(c->parents);
359 /* TODO: what about commit->util? */
360
361 c->object.parsed = 0;
362 }
363
364 const void *detach_commit_buffer(struct commit *commit, unsigned long *sizep)
365 {
366 struct commit_buffer *v = buffer_slab_peek(
367 the_repository->parsed_objects->buffer_slab, commit);
368 void *ret;
369
370 if (!v) {
371 if (sizep)
372 *sizep = 0;
373 return NULL;
374 }
375 ret = v->buffer;
376 if (sizep)
377 *sizep = v->size;
378
379 v->buffer = NULL;
380 v->size = 0;
381 return ret;
382 }
383
384 int parse_commit_buffer(struct repository *r, struct commit *item, const void *buffer, unsigned long size, int check_graph)
385 {
386 const char *tail = buffer;
387 const char *bufptr = buffer;
388 struct object_id parent;
389 struct commit_list **pptr;
390 struct commit_graft *graft;
391 const int tree_entry_len = the_hash_algo->hexsz + 5;
392 const int parent_entry_len = the_hash_algo->hexsz + 7;
393
394 if (item->object.parsed)
395 return 0;
396 item->object.parsed = 1;
397 tail += size;
398 if (tail <= bufptr + tree_entry_len + 1 || memcmp(bufptr, "tree ", 5) ||
399 bufptr[tree_entry_len] != '\n')
400 return error("bogus commit object %s", oid_to_hex(&item->object.oid));
401 if (get_oid_hex(bufptr + 5, &parent) < 0)
402 return error("bad tree pointer in commit %s",
403 oid_to_hex(&item->object.oid));
404 item->maybe_tree = lookup_tree(r, &parent);
405 bufptr += tree_entry_len + 1; /* "tree " + "hex sha1" + "\n" */
406 pptr = &item->parents;
407
408 graft = lookup_commit_graft(r, &item->object.oid);
409 while (bufptr + parent_entry_len < tail && !memcmp(bufptr, "parent ", 7)) {
410 struct commit *new_parent;
411
412 if (tail <= bufptr + parent_entry_len + 1 ||
413 get_oid_hex(bufptr + 7, &parent) ||
414 bufptr[parent_entry_len] != '\n')
415 return error("bad parents in commit %s", oid_to_hex(&item->object.oid));
416 bufptr += parent_entry_len + 1;
417 /*
418 * The clone is shallow if nr_parent < 0, and we must
419 * not traverse its real parents even when we unhide them.
420 */
421 if (graft && (graft->nr_parent < 0 || grafts_replace_parents))
422 continue;
423 new_parent = lookup_commit(r, &parent);
424 if (new_parent)
425 pptr = &commit_list_insert(new_parent, pptr)->next;
426 }
427 if (graft) {
428 int i;
429 struct commit *new_parent;
430 for (i = 0; i < graft->nr_parent; i++) {
431 new_parent = lookup_commit(r,
432 &graft->parent[i]);
433 if (!new_parent)
434 continue;
435 pptr = &commit_list_insert(new_parent, pptr)->next;
436 }
437 }
438 item->date = parse_commit_date(bufptr, tail);
439
440 if (check_graph)
441 load_commit_graph_info(the_repository, item);
442
443 return 0;
444 }
445
446 int parse_commit_internal(struct commit *item, int quiet_on_missing, int use_commit_graph)
447 {
448 enum object_type type;
449 void *buffer;
450 unsigned long size;
451 int ret;
452
453 if (!item)
454 return -1;
455 if (item->object.parsed)
456 return 0;
457 if (use_commit_graph && parse_commit_in_graph(the_repository, item))
458 return 0;
459 buffer = read_object_file(&item->object.oid, &type, &size);
460 if (!buffer)
461 return quiet_on_missing ? -1 :
462 error("Could not read %s",
463 oid_to_hex(&item->object.oid));
464 if (type != OBJ_COMMIT) {
465 free(buffer);
466 return error("Object %s not a commit",
467 oid_to_hex(&item->object.oid));
468 }
469
470 ret = parse_commit_buffer(the_repository, item, buffer, size, 0);
471 if (save_commit_buffer && !ret) {
472 set_commit_buffer(the_repository, item, buffer, size);
473 return 0;
474 }
475 free(buffer);
476 return ret;
477 }
478
479 int parse_commit_gently(struct commit *item, int quiet_on_missing)
480 {
481 return parse_commit_internal(item, quiet_on_missing, 1);
482 }
483
484 void parse_commit_or_die(struct commit *item)
485 {
486 if (parse_commit(item))
487 die("unable to parse commit %s",
488 item ? oid_to_hex(&item->object.oid) : "(null)");
489 }
490
491 int find_commit_subject(const char *commit_buffer, const char **subject)
492 {
493 const char *eol;
494 const char *p = commit_buffer;
495
496 while (*p && (*p != '\n' || p[1] != '\n'))
497 p++;
498 if (*p) {
499 p = skip_blank_lines(p + 2);
500 eol = strchrnul(p, '\n');
501 } else
502 eol = p;
503
504 *subject = p;
505
506 return eol - p;
507 }
508
509 struct commit_list *commit_list_insert(struct commit *item, struct commit_list **list_p)
510 {
511 struct commit_list *new_list = xmalloc(sizeof(struct commit_list));
512 new_list->item = item;
513 new_list->next = *list_p;
514 *list_p = new_list;
515 return new_list;
516 }
517
518 unsigned commit_list_count(const struct commit_list *l)
519 {
520 unsigned c = 0;
521 for (; l; l = l->next )
522 c++;
523 return c;
524 }
525
526 struct commit_list *copy_commit_list(struct commit_list *list)
527 {
528 struct commit_list *head = NULL;
529 struct commit_list **pp = &head;
530 while (list) {
531 pp = commit_list_append(list->item, pp);
532 list = list->next;
533 }
534 return head;
535 }
536
537 void free_commit_list(struct commit_list *list)
538 {
539 while (list)
540 pop_commit(&list);
541 }
542
543 struct commit_list * commit_list_insert_by_date(struct commit *item, struct commit_list **list)
544 {
545 struct commit_list **pp = list;
546 struct commit_list *p;
547 while ((p = *pp) != NULL) {
548 if (p->item->date < item->date) {
549 break;
550 }
551 pp = &p->next;
552 }
553 return commit_list_insert(item, pp);
554 }
555
556 static int commit_list_compare_by_date(const void *a, const void *b)
557 {
558 timestamp_t a_date = ((const struct commit_list *)a)->item->date;
559 timestamp_t b_date = ((const struct commit_list *)b)->item->date;
560 if (a_date < b_date)
561 return 1;
562 if (a_date > b_date)
563 return -1;
564 return 0;
565 }
566
567 static void *commit_list_get_next(const void *a)
568 {
569 return ((const struct commit_list *)a)->next;
570 }
571
572 static void commit_list_set_next(void *a, void *next)
573 {
574 ((struct commit_list *)a)->next = next;
575 }
576
577 void commit_list_sort_by_date(struct commit_list **list)
578 {
579 *list = llist_mergesort(*list, commit_list_get_next, commit_list_set_next,
580 commit_list_compare_by_date);
581 }
582
583 struct commit *pop_most_recent_commit(struct commit_list **list,
584 unsigned int mark)
585 {
586 struct commit *ret = pop_commit(list);
587 struct commit_list *parents = ret->parents;
588
589 while (parents) {
590 struct commit *commit = parents->item;
591 if (!parse_commit(commit) && !(commit->object.flags & mark)) {
592 commit->object.flags |= mark;
593 commit_list_insert_by_date(commit, list);
594 }
595 parents = parents->next;
596 }
597 return ret;
598 }
599
600 static void clear_commit_marks_1(struct commit_list **plist,
601 struct commit *commit, unsigned int mark)
602 {
603 while (commit) {
604 struct commit_list *parents;
605
606 if (!(mark & commit->object.flags))
607 return;
608
609 commit->object.flags &= ~mark;
610
611 parents = commit->parents;
612 if (!parents)
613 return;
614
615 while ((parents = parents->next))
616 commit_list_insert(parents->item, plist);
617
618 commit = commit->parents->item;
619 }
620 }
621
622 void clear_commit_marks_many(int nr, struct commit **commit, unsigned int mark)
623 {
624 struct commit_list *list = NULL;
625
626 while (nr--) {
627 clear_commit_marks_1(&list, *commit, mark);
628 commit++;
629 }
630 while (list)
631 clear_commit_marks_1(&list, pop_commit(&list), mark);
632 }
633
634 void clear_commit_marks(struct commit *commit, unsigned int mark)
635 {
636 clear_commit_marks_many(1, &commit, mark);
637 }
638
639 struct commit *pop_commit(struct commit_list **stack)
640 {
641 struct commit_list *top = *stack;
642 struct commit *item = top ? top->item : NULL;
643
644 if (top) {
645 *stack = top->next;
646 free(top);
647 }
648 return item;
649 }
650
651 /*
652 * Topological sort support
653 */
654
655 /* count number of children that have not been emitted */
656 define_commit_slab(indegree_slab, int);
657
658 /* record author-date for each commit object */
659 define_commit_slab(author_date_slab, timestamp_t);
660
661 static void record_author_date(struct author_date_slab *author_date,
662 struct commit *commit)
663 {
664 const char *buffer = get_commit_buffer(commit, NULL);
665 struct ident_split ident;
666 const char *ident_line;
667 size_t ident_len;
668 char *date_end;
669 timestamp_t date;
670
671 ident_line = find_commit_header(buffer, "author", &ident_len);
672 if (!ident_line)
673 goto fail_exit; /* no author line */
674 if (split_ident_line(&ident, ident_line, ident_len) ||
675 !ident.date_begin || !ident.date_end)
676 goto fail_exit; /* malformed "author" line */
677
678 date = parse_timestamp(ident.date_begin, &date_end, 10);
679 if (date_end != ident.date_end)
680 goto fail_exit; /* malformed date */
681 *(author_date_slab_at(author_date, commit)) = date;
682
683 fail_exit:
684 unuse_commit_buffer(commit, buffer);
685 }
686
687 static int compare_commits_by_author_date(const void *a_, const void *b_,
688 void *cb_data)
689 {
690 const struct commit *a = a_, *b = b_;
691 struct author_date_slab *author_date = cb_data;
692 timestamp_t a_date = *(author_date_slab_at(author_date, a));
693 timestamp_t b_date = *(author_date_slab_at(author_date, b));
694
695 /* newer commits with larger date first */
696 if (a_date < b_date)
697 return 1;
698 else if (a_date > b_date)
699 return -1;
700 return 0;
701 }
702
703 int compare_commits_by_gen_then_commit_date(const void *a_, const void *b_, void *unused)
704 {
705 const struct commit *a = a_, *b = b_;
706
707 /* newer commits first */
708 if (a->generation < b->generation)
709 return 1;
710 else if (a->generation > b->generation)
711 return -1;
712
713 /* use date as a heuristic when generations are equal */
714 if (a->date < b->date)
715 return 1;
716 else if (a->date > b->date)
717 return -1;
718 return 0;
719 }
720
721 int compare_commits_by_commit_date(const void *a_, const void *b_, void *unused)
722 {
723 const struct commit *a = a_, *b = b_;
724 /* newer commits with larger date first */
725 if (a->date < b->date)
726 return 1;
727 else if (a->date > b->date)
728 return -1;
729 return 0;
730 }
731
732 /*
733 * Performs an in-place topological sort on the list supplied.
734 */
735 void sort_in_topological_order(struct commit_list **list, enum rev_sort_order sort_order)
736 {
737 struct commit_list *next, *orig = *list;
738 struct commit_list **pptr;
739 struct indegree_slab indegree;
740 struct prio_queue queue;
741 struct commit *commit;
742 struct author_date_slab author_date;
743
744 if (!orig)
745 return;
746 *list = NULL;
747
748 init_indegree_slab(&indegree);
749 memset(&queue, '\0', sizeof(queue));
750
751 switch (sort_order) {
752 default: /* REV_SORT_IN_GRAPH_ORDER */
753 queue.compare = NULL;
754 break;
755 case REV_SORT_BY_COMMIT_DATE:
756 queue.compare = compare_commits_by_commit_date;
757 break;
758 case REV_SORT_BY_AUTHOR_DATE:
759 init_author_date_slab(&author_date);
760 queue.compare = compare_commits_by_author_date;
761 queue.cb_data = &author_date;
762 break;
763 }
764
765 /* Mark them and clear the indegree */
766 for (next = orig; next; next = next->next) {
767 struct commit *commit = next->item;
768 *(indegree_slab_at(&indegree, commit)) = 1;
769 /* also record the author dates, if needed */
770 if (sort_order == REV_SORT_BY_AUTHOR_DATE)
771 record_author_date(&author_date, commit);
772 }
773
774 /* update the indegree */
775 for (next = orig; next; next = next->next) {
776 struct commit_list *parents = next->item->parents;
777 while (parents) {
778 struct commit *parent = parents->item;
779 int *pi = indegree_slab_at(&indegree, parent);
780
781 if (*pi)
782 (*pi)++;
783 parents = parents->next;
784 }
785 }
786
787 /*
788 * find the tips
789 *
790 * tips are nodes not reachable from any other node in the list
791 *
792 * the tips serve as a starting set for the work queue.
793 */
794 for (next = orig; next; next = next->next) {
795 struct commit *commit = next->item;
796
797 if (*(indegree_slab_at(&indegree, commit)) == 1)
798 prio_queue_put(&queue, commit);
799 }
800
801 /*
802 * This is unfortunate; the initial tips need to be shown
803 * in the order given from the revision traversal machinery.
804 */
805 if (sort_order == REV_SORT_IN_GRAPH_ORDER)
806 prio_queue_reverse(&queue);
807
808 /* We no longer need the commit list */
809 free_commit_list(orig);
810
811 pptr = list;
812 *list = NULL;
813 while ((commit = prio_queue_get(&queue)) != NULL) {
814 struct commit_list *parents;
815
816 for (parents = commit->parents; parents ; parents = parents->next) {
817 struct commit *parent = parents->item;
818 int *pi = indegree_slab_at(&indegree, parent);
819
820 if (!*pi)
821 continue;
822
823 /*
824 * parents are only enqueued for emission
825 * when all their children have been emitted thereby
826 * guaranteeing topological order.
827 */
828 if (--(*pi) == 1)
829 prio_queue_put(&queue, parent);
830 }
831 /*
832 * all children of commit have already been
833 * emitted. we can emit it now.
834 */
835 *(indegree_slab_at(&indegree, commit)) = 0;
836
837 pptr = &commit_list_insert(commit, pptr)->next;
838 }
839
840 clear_indegree_slab(&indegree);
841 clear_prio_queue(&queue);
842 if (sort_order == REV_SORT_BY_AUTHOR_DATE)
843 clear_author_date_slab(&author_date);
844 }
845
846 /* merge-base stuff */
847
848 /* Remember to update object flag allocation in object.h */
849 #define PARENT1 (1u<<16)
850 #define PARENT2 (1u<<17)
851 #define STALE (1u<<18)
852 #define RESULT (1u<<19)
853
854 static const unsigned all_flags = (PARENT1 | PARENT2 | STALE | RESULT);
855
856 static int queue_has_nonstale(struct prio_queue *queue)
857 {
858 int i;
859 for (i = 0; i < queue->nr; i++) {
860 struct commit *commit = queue->array[i].data;
861 if (!(commit->object.flags & STALE))
862 return 1;
863 }
864 return 0;
865 }
866
867 /* all input commits in one and twos[] must have been parsed! */
868 static struct commit_list *paint_down_to_common(struct commit *one, int n,
869 struct commit **twos,
870 int min_generation)
871 {
872 struct prio_queue queue = { compare_commits_by_gen_then_commit_date };
873 struct commit_list *result = NULL;
874 int i;
875 uint32_t last_gen = GENERATION_NUMBER_INFINITY;
876
877 if (!min_generation)
878 queue.compare = compare_commits_by_commit_date;
879
880 one->object.flags |= PARENT1;
881 if (!n) {
882 commit_list_append(one, &result);
883 return result;
884 }
885 prio_queue_put(&queue, one);
886
887 for (i = 0; i < n; i++) {
888 twos[i]->object.flags |= PARENT2;
889 prio_queue_put(&queue, twos[i]);
890 }
891
892 while (queue_has_nonstale(&queue)) {
893 struct commit *commit = prio_queue_get(&queue);
894 struct commit_list *parents;
895 int flags;
896
897 if (min_generation && commit->generation > last_gen)
898 BUG("bad generation skip %8x > %8x at %s",
899 commit->generation, last_gen,
900 oid_to_hex(&commit->object.oid));
901 last_gen = commit->generation;
902
903 if (commit->generation < min_generation)
904 break;
905
906 flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
907 if (flags == (PARENT1 | PARENT2)) {
908 if (!(commit->object.flags & RESULT)) {
909 commit->object.flags |= RESULT;
910 commit_list_insert_by_date(commit, &result);
911 }
912 /* Mark parents of a found merge stale */
913 flags |= STALE;
914 }
915 parents = commit->parents;
916 while (parents) {
917 struct commit *p = parents->item;
918 parents = parents->next;
919 if ((p->object.flags & flags) == flags)
920 continue;
921 if (parse_commit(p))
922 return NULL;
923 p->object.flags |= flags;
924 prio_queue_put(&queue, p);
925 }
926 }
927
928 clear_prio_queue(&queue);
929 return result;
930 }
931
932 static struct commit_list *merge_bases_many(struct commit *one, int n, struct commit **twos)
933 {
934 struct commit_list *list = NULL;
935 struct commit_list *result = NULL;
936 int i;
937
938 for (i = 0; i < n; i++) {
939 if (one == twos[i])
940 /*
941 * We do not mark this even with RESULT so we do not
942 * have to clean it up.
943 */
944 return commit_list_insert(one, &result);
945 }
946
947 if (parse_commit(one))
948 return NULL;
949 for (i = 0; i < n; i++) {
950 if (parse_commit(twos[i]))
951 return NULL;
952 }
953
954 list = paint_down_to_common(one, n, twos, 0);
955
956 while (list) {
957 struct commit *commit = pop_commit(&list);
958 if (!(commit->object.flags & STALE))
959 commit_list_insert_by_date(commit, &result);
960 }
961 return result;
962 }
963
964 struct commit_list *get_octopus_merge_bases(struct commit_list *in)
965 {
966 struct commit_list *i, *j, *k, *ret = NULL;
967
968 if (!in)
969 return ret;
970
971 commit_list_insert(in->item, &ret);
972
973 for (i = in->next; i; i = i->next) {
974 struct commit_list *new_commits = NULL, *end = NULL;
975
976 for (j = ret; j; j = j->next) {
977 struct commit_list *bases;
978 bases = get_merge_bases(i->item, j->item);
979 if (!new_commits)
980 new_commits = bases;
981 else
982 end->next = bases;
983 for (k = bases; k; k = k->next)
984 end = k;
985 }
986 ret = new_commits;
987 }
988 return ret;
989 }
990
991 static int remove_redundant(struct commit **array, int cnt)
992 {
993 /*
994 * Some commit in the array may be an ancestor of
995 * another commit. Move such commit to the end of
996 * the array, and return the number of commits that
997 * are independent from each other.
998 */
999 struct commit **work;
1000 unsigned char *redundant;
1001 int *filled_index;
1002 int i, j, filled;
1003
1004 work = xcalloc(cnt, sizeof(*work));
1005 redundant = xcalloc(cnt, 1);
1006 ALLOC_ARRAY(filled_index, cnt - 1);
1007
1008 for (i = 0; i < cnt; i++)
1009 parse_commit(array[i]);
1010 for (i = 0; i < cnt; i++) {
1011 struct commit_list *common;
1012 uint32_t min_generation = array[i]->generation;
1013
1014 if (redundant[i])
1015 continue;
1016 for (j = filled = 0; j < cnt; j++) {
1017 if (i == j || redundant[j])
1018 continue;
1019 filled_index[filled] = j;
1020 work[filled++] = array[j];
1021
1022 if (array[j]->generation < min_generation)
1023 min_generation = array[j]->generation;
1024 }
1025 common = paint_down_to_common(array[i], filled, work,
1026 min_generation);
1027 if (array[i]->object.flags & PARENT2)
1028 redundant[i] = 1;
1029 for (j = 0; j < filled; j++)
1030 if (work[j]->object.flags & PARENT1)
1031 redundant[filled_index[j]] = 1;
1032 clear_commit_marks(array[i], all_flags);
1033 clear_commit_marks_many(filled, work, all_flags);
1034 free_commit_list(common);
1035 }
1036
1037 /* Now collect the result */
1038 COPY_ARRAY(work, array, cnt);
1039 for (i = filled = 0; i < cnt; i++)
1040 if (!redundant[i])
1041 array[filled++] = work[i];
1042 for (j = filled, i = 0; i < cnt; i++)
1043 if (redundant[i])
1044 array[j++] = work[i];
1045 free(work);
1046 free(redundant);
1047 free(filled_index);
1048 return filled;
1049 }
1050
1051 static struct commit_list *get_merge_bases_many_0(struct commit *one,
1052 int n,
1053 struct commit **twos,
1054 int cleanup)
1055 {
1056 struct commit_list *list;
1057 struct commit **rslt;
1058 struct commit_list *result;
1059 int cnt, i;
1060
1061 result = merge_bases_many(one, n, twos);
1062 for (i = 0; i < n; i++) {
1063 if (one == twos[i])
1064 return result;
1065 }
1066 if (!result || !result->next) {
1067 if (cleanup) {
1068 clear_commit_marks(one, all_flags);
1069 clear_commit_marks_many(n, twos, all_flags);
1070 }
1071 return result;
1072 }
1073
1074 /* There are more than one */
1075 cnt = commit_list_count(result);
1076 rslt = xcalloc(cnt, sizeof(*rslt));
1077 for (list = result, i = 0; list; list = list->next)
1078 rslt[i++] = list->item;
1079 free_commit_list(result);
1080
1081 clear_commit_marks(one, all_flags);
1082 clear_commit_marks_many(n, twos, all_flags);
1083
1084 cnt = remove_redundant(rslt, cnt);
1085 result = NULL;
1086 for (i = 0; i < cnt; i++)
1087 commit_list_insert_by_date(rslt[i], &result);
1088 free(rslt);
1089 return result;
1090 }
1091
1092 struct commit_list *get_merge_bases_many(struct commit *one,
1093 int n,
1094 struct commit **twos)
1095 {
1096 return get_merge_bases_many_0(one, n, twos, 1);
1097 }
1098
1099 struct commit_list *get_merge_bases_many_dirty(struct commit *one,
1100 int n,
1101 struct commit **twos)
1102 {
1103 return get_merge_bases_many_0(one, n, twos, 0);
1104 }
1105
1106 struct commit_list *get_merge_bases(struct commit *one, struct commit *two)
1107 {
1108 return get_merge_bases_many_0(one, 1, &two, 1);
1109 }
1110
1111 /*
1112 * Is "commit" a descendant of one of the elements on the "with_commit" list?
1113 */
1114 int is_descendant_of(struct commit *commit, struct commit_list *with_commit)
1115 {
1116 if (!with_commit)
1117 return 1;
1118 while (with_commit) {
1119 struct commit *other;
1120
1121 other = with_commit->item;
1122 with_commit = with_commit->next;
1123 if (in_merge_bases(other, commit))
1124 return 1;
1125 }
1126 return 0;
1127 }
1128
1129 /*
1130 * Is "commit" an ancestor of one of the "references"?
1131 */
1132 int in_merge_bases_many(struct commit *commit, int nr_reference, struct commit **reference)
1133 {
1134 struct commit_list *bases;
1135 int ret = 0, i;
1136 uint32_t min_generation = GENERATION_NUMBER_INFINITY;
1137
1138 if (parse_commit(commit))
1139 return ret;
1140 for (i = 0; i < nr_reference; i++) {
1141 if (parse_commit(reference[i]))
1142 return ret;
1143 if (reference[i]->generation < min_generation)
1144 min_generation = reference[i]->generation;
1145 }
1146
1147 if (commit->generation > min_generation)
1148 return ret;
1149
1150 bases = paint_down_to_common(commit, nr_reference, reference, commit->generation);
1151 if (commit->object.flags & PARENT2)
1152 ret = 1;
1153 clear_commit_marks(commit, all_flags);
1154 clear_commit_marks_many(nr_reference, reference, all_flags);
1155 free_commit_list(bases);
1156 return ret;
1157 }
1158
1159 /*
1160 * Is "commit" an ancestor of (i.e. reachable from) the "reference"?
1161 */
1162 int in_merge_bases(struct commit *commit, struct commit *reference)
1163 {
1164 return in_merge_bases_many(commit, 1, &reference);
1165 }
1166
1167 struct commit_list *reduce_heads(struct commit_list *heads)
1168 {
1169 struct commit_list *p;
1170 struct commit_list *result = NULL, **tail = &result;
1171 struct commit **array;
1172 int num_head, i;
1173
1174 if (!heads)
1175 return NULL;
1176
1177 /* Uniquify */
1178 for (p = heads; p; p = p->next)
1179 p->item->object.flags &= ~STALE;
1180 for (p = heads, num_head = 0; p; p = p->next) {
1181 if (p->item->object.flags & STALE)
1182 continue;
1183 p->item->object.flags |= STALE;
1184 num_head++;
1185 }
1186 array = xcalloc(num_head, sizeof(*array));
1187 for (p = heads, i = 0; p; p = p->next) {
1188 if (p->item->object.flags & STALE) {
1189 array[i++] = p->item;
1190 p->item->object.flags &= ~STALE;
1191 }
1192 }
1193 num_head = remove_redundant(array, num_head);
1194 for (i = 0; i < num_head; i++)
1195 tail = &commit_list_insert(array[i], tail)->next;
1196 free(array);
1197 return result;
1198 }
1199
1200 void reduce_heads_replace(struct commit_list **heads)
1201 {
1202 struct commit_list *result = reduce_heads(*heads);
1203 free_commit_list(*heads);
1204 *heads = result;
1205 }
1206
1207 static const char gpg_sig_header[] = "gpgsig";
1208 static const int gpg_sig_header_len = sizeof(gpg_sig_header) - 1;
1209
1210 static int do_sign_commit(struct strbuf *buf, const char *keyid)
1211 {
1212 struct strbuf sig = STRBUF_INIT;
1213 int inspos, copypos;
1214 const char *eoh;
1215
1216 /* find the end of the header */
1217 eoh = strstr(buf->buf, "\n\n");
1218 if (!eoh)
1219 inspos = buf->len;
1220 else
1221 inspos = eoh - buf->buf + 1;
1222
1223 if (!keyid || !*keyid)
1224 keyid = get_signing_key();
1225 if (sign_buffer(buf, &sig, keyid)) {
1226 strbuf_release(&sig);
1227 return -1;
1228 }
1229
1230 for (copypos = 0; sig.buf[copypos]; ) {
1231 const char *bol = sig.buf + copypos;
1232 const char *eol = strchrnul(bol, '\n');
1233 int len = (eol - bol) + !!*eol;
1234
1235 if (!copypos) {
1236 strbuf_insert(buf, inspos, gpg_sig_header, gpg_sig_header_len);
1237 inspos += gpg_sig_header_len;
1238 }
1239 strbuf_insert(buf, inspos++, " ", 1);
1240 strbuf_insert(buf, inspos, bol, len);
1241 inspos += len;
1242 copypos += len;
1243 }
1244 strbuf_release(&sig);
1245 return 0;
1246 }
1247
1248 int parse_signed_commit(const struct commit *commit,
1249 struct strbuf *payload, struct strbuf *signature)
1250 {
1251
1252 unsigned long size;
1253 const char *buffer = get_commit_buffer(commit, &size);
1254 int in_signature, saw_signature = -1;
1255 const char *line, *tail;
1256
1257 line = buffer;
1258 tail = buffer + size;
1259 in_signature = 0;
1260 saw_signature = 0;
1261 while (line < tail) {
1262 const char *sig = NULL;
1263 const char *next = memchr(line, '\n', tail - line);
1264
1265 next = next ? next + 1 : tail;
1266 if (in_signature && line[0] == ' ')
1267 sig = line + 1;
1268 else if (starts_with(line, gpg_sig_header) &&
1269 line[gpg_sig_header_len] == ' ')
1270 sig = line + gpg_sig_header_len + 1;
1271 if (sig) {
1272 strbuf_add(signature, sig, next - sig);
1273 saw_signature = 1;
1274 in_signature = 1;
1275 } else {
1276 if (*line == '\n')
1277 /* dump the whole remainder of the buffer */
1278 next = tail;
1279 strbuf_add(payload, line, next - line);
1280 in_signature = 0;
1281 }
1282 line = next;
1283 }
1284 unuse_commit_buffer(commit, buffer);
1285 return saw_signature;
1286 }
1287
1288 int remove_signature(struct strbuf *buf)
1289 {
1290 const char *line = buf->buf;
1291 const char *tail = buf->buf + buf->len;
1292 int in_signature = 0;
1293 const char *sig_start = NULL;
1294 const char *sig_end = NULL;
1295
1296 while (line < tail) {
1297 const char *next = memchr(line, '\n', tail - line);
1298 next = next ? next + 1 : tail;
1299
1300 if (in_signature && line[0] == ' ')
1301 sig_end = next;
1302 else if (starts_with(line, gpg_sig_header) &&
1303 line[gpg_sig_header_len] == ' ') {
1304 sig_start = line;
1305 sig_end = next;
1306 in_signature = 1;
1307 } else {
1308 if (*line == '\n')
1309 /* dump the whole remainder of the buffer */
1310 next = tail;
1311 in_signature = 0;
1312 }
1313 line = next;
1314 }
1315
1316 if (sig_start)
1317 strbuf_remove(buf, sig_start - buf->buf, sig_end - sig_start);
1318
1319 return sig_start != NULL;
1320 }
1321
1322 static void handle_signed_tag(struct commit *parent, struct commit_extra_header ***tail)
1323 {
1324 struct merge_remote_desc *desc;
1325 struct commit_extra_header *mergetag;
1326 char *buf;
1327 unsigned long size, len;
1328 enum object_type type;
1329
1330 desc = merge_remote_util(parent);
1331 if (!desc || !desc->obj)
1332 return;
1333 buf = read_object_file(&desc->obj->oid, &type, &size);
1334 if (!buf || type != OBJ_TAG)
1335 goto free_return;
1336 len = parse_signature(buf, size);
1337 if (size == len)
1338 goto free_return;
1339 /*
1340 * We could verify this signature and either omit the tag when
1341 * it does not validate, but the integrator may not have the
1342 * public key of the signer of the tag he is merging, while a
1343 * later auditor may have it while auditing, so let's not run
1344 * verify-signed-buffer here for now...
1345 *
1346 * if (verify_signed_buffer(buf, len, buf + len, size - len, ...))
1347 * warn("warning: signed tag unverified.");
1348 */
1349 mergetag = xcalloc(1, sizeof(*mergetag));
1350 mergetag->key = xstrdup("mergetag");
1351 mergetag->value = buf;
1352 mergetag->len = size;
1353
1354 **tail = mergetag;
1355 *tail = &mergetag->next;
1356 return;
1357
1358 free_return:
1359 free(buf);
1360 }
1361
1362 int check_commit_signature(const struct commit *commit, struct signature_check *sigc)
1363 {
1364 struct strbuf payload = STRBUF_INIT;
1365 struct strbuf signature = STRBUF_INIT;
1366 int ret = 1;
1367
1368 sigc->result = 'N';
1369
1370 if (parse_signed_commit(commit, &payload, &signature) <= 0)
1371 goto out;
1372 ret = check_signature(payload.buf, payload.len, signature.buf,
1373 signature.len, sigc);
1374
1375 out:
1376 strbuf_release(&payload);
1377 strbuf_release(&signature);
1378
1379 return ret;
1380 }
1381
1382
1383
1384 void append_merge_tag_headers(struct commit_list *parents,
1385 struct commit_extra_header ***tail)
1386 {
1387 while (parents) {
1388 struct commit *parent = parents->item;
1389 handle_signed_tag(parent, tail);
1390 parents = parents->next;
1391 }
1392 }
1393
1394 static void add_extra_header(struct strbuf *buffer,
1395 struct commit_extra_header *extra)
1396 {
1397 strbuf_addstr(buffer, extra->key);
1398 if (extra->len)
1399 strbuf_add_lines(buffer, " ", extra->value, extra->len);
1400 else
1401 strbuf_addch(buffer, '\n');
1402 }
1403
1404 struct commit_extra_header *read_commit_extra_headers(struct commit *commit,
1405 const char **exclude)
1406 {
1407 struct commit_extra_header *extra = NULL;
1408 unsigned long size;
1409 const char *buffer = get_commit_buffer(commit, &size);
1410 extra = read_commit_extra_header_lines(buffer, size, exclude);
1411 unuse_commit_buffer(commit, buffer);
1412 return extra;
1413 }
1414
1415 int for_each_mergetag(each_mergetag_fn fn, struct commit *commit, void *data)
1416 {
1417 struct commit_extra_header *extra, *to_free;
1418 int res = 0;
1419
1420 to_free = read_commit_extra_headers(commit, NULL);
1421 for (extra = to_free; !res && extra; extra = extra->next) {
1422 if (strcmp(extra->key, "mergetag"))
1423 continue; /* not a merge tag */
1424 res = fn(commit, extra, data);
1425 }
1426 free_commit_extra_headers(to_free);
1427 return res;
1428 }
1429
1430 static inline int standard_header_field(const char *field, size_t len)
1431 {
1432 return ((len == 4 && !memcmp(field, "tree", 4)) ||
1433 (len == 6 && !memcmp(field, "parent", 6)) ||
1434 (len == 6 && !memcmp(field, "author", 6)) ||
1435 (len == 9 && !memcmp(field, "committer", 9)) ||
1436 (len == 8 && !memcmp(field, "encoding", 8)));
1437 }
1438
1439 static int excluded_header_field(const char *field, size_t len, const char **exclude)
1440 {
1441 if (!exclude)
1442 return 0;
1443
1444 while (*exclude) {
1445 size_t xlen = strlen(*exclude);
1446 if (len == xlen && !memcmp(field, *exclude, xlen))
1447 return 1;
1448 exclude++;
1449 }
1450 return 0;
1451 }
1452
1453 static struct commit_extra_header *read_commit_extra_header_lines(
1454 const char *buffer, size_t size,
1455 const char **exclude)
1456 {
1457 struct commit_extra_header *extra = NULL, **tail = &extra, *it = NULL;
1458 const char *line, *next, *eof, *eob;
1459 struct strbuf buf = STRBUF_INIT;
1460
1461 for (line = buffer, eob = line + size;
1462 line < eob && *line != '\n';
1463 line = next) {
1464 next = memchr(line, '\n', eob - line);
1465 next = next ? next + 1 : eob;
1466 if (*line == ' ') {
1467 /* continuation */
1468 if (it)
1469 strbuf_add(&buf, line + 1, next - (line + 1));
1470 continue;
1471 }
1472 if (it)
1473 it->value = strbuf_detach(&buf, &it->len);
1474 strbuf_reset(&buf);
1475 it = NULL;
1476
1477 eof = memchr(line, ' ', next - line);
1478 if (!eof)
1479 eof = next;
1480 else if (standard_header_field(line, eof - line) ||
1481 excluded_header_field(line, eof - line, exclude))
1482 continue;
1483
1484 it = xcalloc(1, sizeof(*it));
1485 it->key = xmemdupz(line, eof-line);
1486 *tail = it;
1487 tail = &it->next;
1488 if (eof + 1 < next)
1489 strbuf_add(&buf, eof + 1, next - (eof + 1));
1490 }
1491 if (it)
1492 it->value = strbuf_detach(&buf, &it->len);
1493 return extra;
1494 }
1495
1496 void free_commit_extra_headers(struct commit_extra_header *extra)
1497 {
1498 while (extra) {
1499 struct commit_extra_header *next = extra->next;
1500 free(extra->key);
1501 free(extra->value);
1502 free(extra);
1503 extra = next;
1504 }
1505 }
1506
1507 int commit_tree(const char *msg, size_t msg_len, const struct object_id *tree,
1508 struct commit_list *parents, struct object_id *ret,
1509 const char *author, const char *sign_commit)
1510 {
1511 struct commit_extra_header *extra = NULL, **tail = &extra;
1512 int result;
1513
1514 append_merge_tag_headers(parents, &tail);
1515 result = commit_tree_extended(msg, msg_len, tree, parents, ret,
1516 author, sign_commit, extra);
1517 free_commit_extra_headers(extra);
1518 return result;
1519 }
1520
1521 static int find_invalid_utf8(const char *buf, int len)
1522 {
1523 int offset = 0;
1524 static const unsigned int max_codepoint[] = {
1525 0x7f, 0x7ff, 0xffff, 0x10ffff
1526 };
1527
1528 while (len) {
1529 unsigned char c = *buf++;
1530 int bytes, bad_offset;
1531 unsigned int codepoint;
1532 unsigned int min_val, max_val;
1533
1534 len--;
1535 offset++;
1536
1537 /* Simple US-ASCII? No worries. */
1538 if (c < 0x80)
1539 continue;
1540
1541 bad_offset = offset-1;
1542
1543 /*
1544 * Count how many more high bits set: that's how
1545 * many more bytes this sequence should have.
1546 */
1547 bytes = 0;
1548 while (c & 0x40) {
1549 c <<= 1;
1550 bytes++;
1551 }
1552
1553 /*
1554 * Must be between 1 and 3 more bytes. Longer sequences result in
1555 * codepoints beyond U+10FFFF, which are guaranteed never to exist.
1556 */
1557 if (bytes < 1 || 3 < bytes)
1558 return bad_offset;
1559
1560 /* Do we *have* that many bytes? */
1561 if (len < bytes)
1562 return bad_offset;
1563
1564 /*
1565 * Place the encoded bits at the bottom of the value and compute the
1566 * valid range.
1567 */
1568 codepoint = (c & 0x7f) >> bytes;
1569 min_val = max_codepoint[bytes-1] + 1;
1570 max_val = max_codepoint[bytes];
1571
1572 offset += bytes;
1573 len -= bytes;
1574
1575 /* And verify that they are good continuation bytes */
1576 do {
1577 codepoint <<= 6;
1578 codepoint |= *buf & 0x3f;
1579 if ((*buf++ & 0xc0) != 0x80)
1580 return bad_offset;
1581 } while (--bytes);
1582
1583 /* Reject codepoints that are out of range for the sequence length. */
1584 if (codepoint < min_val || codepoint > max_val)
1585 return bad_offset;
1586 /* Surrogates are only for UTF-16 and cannot be encoded in UTF-8. */
1587 if ((codepoint & 0x1ff800) == 0xd800)
1588 return bad_offset;
1589 /* U+xxFFFE and U+xxFFFF are guaranteed non-characters. */
1590 if ((codepoint & 0xfffe) == 0xfffe)
1591 return bad_offset;
1592 /* So are anything in the range U+FDD0..U+FDEF. */
1593 if (codepoint >= 0xfdd0 && codepoint <= 0xfdef)
1594 return bad_offset;
1595 }
1596 return -1;
1597 }
1598
1599 /*
1600 * This verifies that the buffer is in proper utf8 format.
1601 *
1602 * If it isn't, it assumes any non-utf8 characters are Latin1,
1603 * and does the conversion.
1604 */
1605 static int verify_utf8(struct strbuf *buf)
1606 {
1607 int ok = 1;
1608 long pos = 0;
1609
1610 for (;;) {
1611 int bad;
1612 unsigned char c;
1613 unsigned char replace[2];
1614
1615 bad = find_invalid_utf8(buf->buf + pos, buf->len - pos);
1616 if (bad < 0)
1617 return ok;
1618 pos += bad;
1619 ok = 0;
1620 c = buf->buf[pos];
1621 strbuf_remove(buf, pos, 1);
1622
1623 /* We know 'c' must be in the range 128-255 */
1624 replace[0] = 0xc0 + (c >> 6);
1625 replace[1] = 0x80 + (c & 0x3f);
1626 strbuf_insert(buf, pos, replace, 2);
1627 pos += 2;
1628 }
1629 }
1630
1631 static const char commit_utf8_warn[] =
1632 N_("Warning: commit message did not conform to UTF-8.\n"
1633 "You may want to amend it after fixing the message, or set the config\n"
1634 "variable i18n.commitencoding to the encoding your project uses.\n");
1635
1636 int commit_tree_extended(const char *msg, size_t msg_len,
1637 const struct object_id *tree,
1638 struct commit_list *parents, struct object_id *ret,
1639 const char *author, const char *sign_commit,
1640 struct commit_extra_header *extra)
1641 {
1642 int result;
1643 int encoding_is_utf8;
1644 struct strbuf buffer;
1645
1646 assert_oid_type(tree, OBJ_TREE);
1647
1648 if (memchr(msg, '\0', msg_len))
1649 return error("a NUL byte in commit log message not allowed.");
1650
1651 /* Not having i18n.commitencoding is the same as having utf-8 */
1652 encoding_is_utf8 = is_encoding_utf8(git_commit_encoding);
1653
1654 strbuf_init(&buffer, 8192); /* should avoid reallocs for the headers */
1655 strbuf_addf(&buffer, "tree %s\n", oid_to_hex(tree));
1656
1657 /*
1658 * NOTE! This ordering means that the same exact tree merged with a
1659 * different order of parents will be a _different_ changeset even
1660 * if everything else stays the same.
1661 */
1662 while (parents) {
1663 struct commit *parent = pop_commit(&parents);
1664 strbuf_addf(&buffer, "parent %s\n",
1665 oid_to_hex(&parent->object.oid));
1666 }
1667
1668 /* Person/date information */
1669 if (!author)
1670 author = git_author_info(IDENT_STRICT);
1671 strbuf_addf(&buffer, "author %s\n", author);
1672 strbuf_addf(&buffer, "committer %s\n", git_committer_info(IDENT_STRICT));
1673 if (!encoding_is_utf8)
1674 strbuf_addf(&buffer, "encoding %s\n", git_commit_encoding);
1675
1676 while (extra) {
1677 add_extra_header(&buffer, extra);
1678 extra = extra->next;
1679 }
1680 strbuf_addch(&buffer, '\n');
1681
1682 /* And add the comment */
1683 strbuf_add(&buffer, msg, msg_len);
1684
1685 /* And check the encoding */
1686 if (encoding_is_utf8 && !verify_utf8(&buffer))
1687 fprintf(stderr, _(commit_utf8_warn));
1688
1689 if (sign_commit && do_sign_commit(&buffer, sign_commit)) {
1690 result = -1;
1691 goto out;
1692 }
1693
1694 result = write_object_file(buffer.buf, buffer.len, commit_type, ret);
1695 out:
1696 strbuf_release(&buffer);
1697 return result;
1698 }
1699
1700 define_commit_slab(merge_desc_slab, struct merge_remote_desc *);
1701 static struct merge_desc_slab merge_desc_slab = COMMIT_SLAB_INIT(1, merge_desc_slab);
1702
1703 struct merge_remote_desc *merge_remote_util(struct commit *commit)
1704 {
1705 return *merge_desc_slab_at(&merge_desc_slab, commit);
1706 }
1707
1708 void set_merge_remote_desc(struct commit *commit,
1709 const char *name, struct object *obj)
1710 {
1711 struct merge_remote_desc *desc;
1712 FLEX_ALLOC_STR(desc, name, name);
1713 desc->obj = obj;
1714 *merge_desc_slab_at(&merge_desc_slab, commit) = desc;
1715 }
1716
1717 struct commit *get_merge_parent(const char *name)
1718 {
1719 struct object *obj;
1720 struct commit *commit;
1721 struct object_id oid;
1722 if (get_oid(name, &oid))
1723 return NULL;
1724 obj = parse_object(the_repository, &oid);
1725 commit = (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
1726 if (commit && !merge_remote_util(commit))
1727 set_merge_remote_desc(commit, name, obj);
1728 return commit;
1729 }
1730
1731 /*
1732 * Append a commit to the end of the commit_list.
1733 *
1734 * next starts by pointing to the variable that holds the head of an
1735 * empty commit_list, and is updated to point to the "next" field of
1736 * the last item on the list as new commits are appended.
1737 *
1738 * Usage example:
1739 *
1740 * struct commit_list *list;
1741 * struct commit_list **next = &list;
1742 *
1743 * next = commit_list_append(c1, next);
1744 * next = commit_list_append(c2, next);
1745 * assert(commit_list_count(list) == 2);
1746 * return list;
1747 */
1748 struct commit_list **commit_list_append(struct commit *commit,
1749 struct commit_list **next)
1750 {
1751 struct commit_list *new_commit = xmalloc(sizeof(struct commit_list));
1752 new_commit->item = commit;
1753 *next = new_commit;
1754 new_commit->next = NULL;
1755 return &new_commit->next;
1756 }
1757
1758 const char *find_commit_header(const char *msg, const char *key, size_t *out_len)
1759 {
1760 int key_len = strlen(key);
1761 const char *line = msg;
1762
1763 while (line) {
1764 const char *eol = strchrnul(line, '\n');
1765
1766 if (line == eol)
1767 return NULL;
1768
1769 if (eol - line > key_len &&
1770 !strncmp(line, key, key_len) &&
1771 line[key_len] == ' ') {
1772 *out_len = eol - line - key_len - 1;
1773 return line + key_len + 1;
1774 }
1775 line = *eol ? eol + 1 : NULL;
1776 }
1777 return NULL;
1778 }
1779
1780 /*
1781 * Inspect the given string and determine the true "end" of the log message, in
1782 * order to find where to put a new Signed-off-by: line. Ignored are
1783 * trailing comment lines and blank lines. To support "git commit -s
1784 * --amend" on an existing commit, we also ignore "Conflicts:". To
1785 * support "git commit -v", we truncate at cut lines.
1786 *
1787 * Returns the number of bytes from the tail to ignore, to be fed as
1788 * the second parameter to append_signoff().
1789 */
1790 size_t ignore_non_trailer(const char *buf, size_t len)
1791 {
1792 size_t boc = 0;
1793 size_t bol = 0;
1794 int in_old_conflicts_block = 0;
1795 size_t cutoff = wt_status_locate_end(buf, len);
1796
1797 while (bol < cutoff) {
1798 const char *next_line = memchr(buf + bol, '\n', len - bol);
1799
1800 if (!next_line)
1801 next_line = buf + len;
1802 else
1803 next_line++;
1804
1805 if (buf[bol] == comment_line_char || buf[bol] == '\n') {
1806 /* is this the first of the run of comments? */
1807 if (!boc)
1808 boc = bol;
1809 /* otherwise, it is just continuing */
1810 } else if (starts_with(buf + bol, "Conflicts:\n")) {
1811 in_old_conflicts_block = 1;
1812 if (!boc)
1813 boc = bol;
1814 } else if (in_old_conflicts_block && buf[bol] == '\t') {
1815 ; /* a pathname in the conflicts block */
1816 } else if (boc) {
1817 /* the previous was not trailing comment */
1818 boc = 0;
1819 in_old_conflicts_block = 0;
1820 }
1821 bol = next_line - buf;
1822 }
1823 return boc ? len - boc : len - cutoff;
1824 }