658471385cfaa2480ee78b19fe38fc51d9b51ab2
[git/git.git] / revision.c
1 #include "cache.h"
2 #include "tag.h"
3 #include "blob.h"
4 #include "tree.h"
5 #include "commit.h"
6 #include "diff.h"
7 #include "refs.h"
8 #include "revision.h"
9 #include "grep.h"
10 #include "reflog-walk.h"
11 #include "patch-ids.h"
12
13 static char *path_name(struct name_path *path, const char *name)
14 {
15 struct name_path *p;
16 char *n, *m;
17 int nlen = strlen(name);
18 int len = nlen + 1;
19
20 for (p = path; p; p = p->up) {
21 if (p->elem_len)
22 len += p->elem_len + 1;
23 }
24 n = xmalloc(len);
25 m = n + len - (nlen + 1);
26 strcpy(m, name);
27 for (p = path; p; p = p->up) {
28 if (p->elem_len) {
29 m -= p->elem_len + 1;
30 memcpy(m, p->elem, p->elem_len);
31 m[p->elem_len] = '/';
32 }
33 }
34 return n;
35 }
36
37 void add_object(struct object *obj,
38 struct object_array *p,
39 struct name_path *path,
40 const char *name)
41 {
42 add_object_array(obj, path_name(path, name), p);
43 }
44
45 static void mark_blob_uninteresting(struct blob *blob)
46 {
47 if (blob->object.flags & UNINTERESTING)
48 return;
49 blob->object.flags |= UNINTERESTING;
50 }
51
52 void mark_tree_uninteresting(struct tree *tree)
53 {
54 struct tree_desc desc;
55 struct name_entry entry;
56 struct object *obj = &tree->object;
57
58 if (obj->flags & UNINTERESTING)
59 return;
60 obj->flags |= UNINTERESTING;
61 if (!has_sha1_file(obj->sha1))
62 return;
63 if (parse_tree(tree) < 0)
64 die("bad tree %s", sha1_to_hex(obj->sha1));
65
66 init_tree_desc(&desc, tree->buffer, tree->size);
67 while (tree_entry(&desc, &entry)) {
68 if (S_ISDIR(entry.mode))
69 mark_tree_uninteresting(lookup_tree(entry.sha1));
70 else
71 mark_blob_uninteresting(lookup_blob(entry.sha1));
72 }
73
74 /*
75 * We don't care about the tree any more
76 * after it has been marked uninteresting.
77 */
78 free(tree->buffer);
79 tree->buffer = NULL;
80 }
81
82 void mark_parents_uninteresting(struct commit *commit)
83 {
84 struct commit_list *parents = commit->parents;
85
86 while (parents) {
87 struct commit *commit = parents->item;
88 if (!(commit->object.flags & UNINTERESTING)) {
89 commit->object.flags |= UNINTERESTING;
90
91 /*
92 * Normally we haven't parsed the parent
93 * yet, so we won't have a parent of a parent
94 * here. However, it may turn out that we've
95 * reached this commit some other way (where it
96 * wasn't uninteresting), in which case we need
97 * to mark its parents recursively too..
98 */
99 if (commit->parents)
100 mark_parents_uninteresting(commit);
101 }
102
103 /*
104 * A missing commit is ok iff its parent is marked
105 * uninteresting.
106 *
107 * We just mark such a thing parsed, so that when
108 * it is popped next time around, we won't be trying
109 * to parse it and get an error.
110 */
111 if (!has_sha1_file(commit->object.sha1))
112 commit->object.parsed = 1;
113 parents = parents->next;
114 }
115 }
116
117 static void add_pending_object_with_mode(struct rev_info *revs, struct object *obj, const char *name, unsigned mode)
118 {
119 if (revs->no_walk && (obj->flags & UNINTERESTING))
120 die("object ranges do not make sense when not walking revisions");
121 if (revs->reflog_info && obj->type == OBJ_COMMIT &&
122 add_reflog_for_walk(revs->reflog_info,
123 (struct commit *)obj, name))
124 return;
125 add_object_array_with_mode(obj, name, &revs->pending, mode);
126 }
127
128 void add_pending_object(struct rev_info *revs, struct object *obj, const char *name)
129 {
130 add_pending_object_with_mode(revs, obj, name, S_IFINVALID);
131 }
132
133 static struct object *get_reference(struct rev_info *revs, const char *name, const unsigned char *sha1, unsigned int flags)
134 {
135 struct object *object;
136
137 object = parse_object(sha1);
138 if (!object)
139 die("bad object %s", name);
140 object->flags |= flags;
141 return object;
142 }
143
144 static struct commit *handle_commit(struct rev_info *revs, struct object *object, const char *name)
145 {
146 unsigned long flags = object->flags;
147
148 /*
149 * Tag object? Look what it points to..
150 */
151 while (object->type == OBJ_TAG) {
152 struct tag *tag = (struct tag *) object;
153 if (revs->tag_objects && !(flags & UNINTERESTING))
154 add_pending_object(revs, object, tag->tag);
155 object = parse_object(tag->tagged->sha1);
156 if (!object)
157 die("bad object %s", sha1_to_hex(tag->tagged->sha1));
158 }
159
160 /*
161 * Commit object? Just return it, we'll do all the complex
162 * reachability crud.
163 */
164 if (object->type == OBJ_COMMIT) {
165 struct commit *commit = (struct commit *)object;
166 if (parse_commit(commit) < 0)
167 die("unable to parse commit %s", name);
168 if (flags & UNINTERESTING) {
169 commit->object.flags |= UNINTERESTING;
170 mark_parents_uninteresting(commit);
171 revs->limited = 1;
172 }
173 return commit;
174 }
175
176 /*
177 * Tree object? Either mark it uniniteresting, or add it
178 * to the list of objects to look at later..
179 */
180 if (object->type == OBJ_TREE) {
181 struct tree *tree = (struct tree *)object;
182 if (!revs->tree_objects)
183 return NULL;
184 if (flags & UNINTERESTING) {
185 mark_tree_uninteresting(tree);
186 return NULL;
187 }
188 add_pending_object(revs, object, "");
189 return NULL;
190 }
191
192 /*
193 * Blob object? You know the drill by now..
194 */
195 if (object->type == OBJ_BLOB) {
196 struct blob *blob = (struct blob *)object;
197 if (!revs->blob_objects)
198 return NULL;
199 if (flags & UNINTERESTING) {
200 mark_blob_uninteresting(blob);
201 return NULL;
202 }
203 add_pending_object(revs, object, "");
204 return NULL;
205 }
206 die("%s is unknown object", name);
207 }
208
209 static int everybody_uninteresting(struct commit_list *orig)
210 {
211 struct commit_list *list = orig;
212 while (list) {
213 struct commit *commit = list->item;
214 list = list->next;
215 if (commit->object.flags & UNINTERESTING)
216 continue;
217 return 0;
218 }
219 return 1;
220 }
221
222 /*
223 * The goal is to get REV_TREE_NEW as the result only if the
224 * diff consists of all '+' (and no other changes), and
225 * REV_TREE_DIFFERENT otherwise (of course if the trees are
226 * the same we want REV_TREE_SAME). That means that once we
227 * get to REV_TREE_DIFFERENT, we do not have to look any further.
228 */
229 static int tree_difference = REV_TREE_SAME;
230
231 static void file_add_remove(struct diff_options *options,
232 int addremove, unsigned mode,
233 const unsigned char *sha1,
234 const char *base, const char *path)
235 {
236 int diff = REV_TREE_DIFFERENT;
237
238 /*
239 * Is it an add of a new file? It means that the old tree
240 * didn't have it at all, so we will turn "REV_TREE_SAME" ->
241 * "REV_TREE_NEW", but leave any "REV_TREE_DIFFERENT" alone
242 * (and if it already was "REV_TREE_NEW", we'll keep it
243 * "REV_TREE_NEW" of course).
244 */
245 if (addremove == '+') {
246 diff = tree_difference;
247 if (diff != REV_TREE_SAME)
248 return;
249 diff = REV_TREE_NEW;
250 }
251 tree_difference = diff;
252 if (tree_difference == REV_TREE_DIFFERENT)
253 options->has_changes = 1;
254 }
255
256 static void file_change(struct diff_options *options,
257 unsigned old_mode, unsigned new_mode,
258 const unsigned char *old_sha1,
259 const unsigned char *new_sha1,
260 const char *base, const char *path)
261 {
262 tree_difference = REV_TREE_DIFFERENT;
263 options->has_changes = 1;
264 }
265
266 static int rev_compare_tree(struct rev_info *revs, struct tree *t1, struct tree *t2)
267 {
268 if (!t1)
269 return REV_TREE_NEW;
270 if (!t2)
271 return REV_TREE_DIFFERENT;
272 tree_difference = REV_TREE_SAME;
273 revs->pruning.has_changes = 0;
274 if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "",
275 &revs->pruning) < 0)
276 return REV_TREE_DIFFERENT;
277 return tree_difference;
278 }
279
280 static int rev_same_tree_as_empty(struct rev_info *revs, struct tree *t1)
281 {
282 int retval;
283 void *tree;
284 unsigned long size;
285 struct tree_desc empty, real;
286
287 if (!t1)
288 return 0;
289
290 tree = read_object_with_reference(t1->object.sha1, tree_type, &size, NULL);
291 if (!tree)
292 return 0;
293 init_tree_desc(&real, tree, size);
294 init_tree_desc(&empty, "", 0);
295
296 tree_difference = REV_TREE_SAME;
297 revs->pruning.has_changes = 0;
298 retval = diff_tree(&empty, &real, "", &revs->pruning);
299 free(tree);
300
301 return retval >= 0 && (tree_difference == REV_TREE_SAME);
302 }
303
304 static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
305 {
306 struct commit_list **pp, *parent;
307 int tree_changed = 0, tree_same = 0;
308
309 if (!commit->tree)
310 return;
311
312 if (!commit->parents) {
313 if (!rev_same_tree_as_empty(revs, commit->tree))
314 commit->object.flags |= TREECHANGE;
315 return;
316 }
317
318 pp = &commit->parents;
319 while ((parent = *pp) != NULL) {
320 struct commit *p = parent->item;
321
322 if (parse_commit(p) < 0)
323 die("cannot simplify commit %s (because of %s)",
324 sha1_to_hex(commit->object.sha1),
325 sha1_to_hex(p->object.sha1));
326 switch (rev_compare_tree(revs, p->tree, commit->tree)) {
327 case REV_TREE_SAME:
328 tree_same = 1;
329 if (!revs->simplify_history || (p->object.flags & UNINTERESTING)) {
330 /* Even if a merge with an uninteresting
331 * side branch brought the entire change
332 * we are interested in, we do not want
333 * to lose the other branches of this
334 * merge, so we just keep going.
335 */
336 pp = &parent->next;
337 continue;
338 }
339 parent->next = NULL;
340 commit->parents = parent;
341 return;
342
343 case REV_TREE_NEW:
344 if (revs->remove_empty_trees &&
345 rev_same_tree_as_empty(revs, p->tree)) {
346 /* We are adding all the specified
347 * paths from this parent, so the
348 * history beyond this parent is not
349 * interesting. Remove its parents
350 * (they are grandparents for us).
351 * IOW, we pretend this parent is a
352 * "root" commit.
353 */
354 if (parse_commit(p) < 0)
355 die("cannot simplify commit %s (invalid %s)",
356 sha1_to_hex(commit->object.sha1),
357 sha1_to_hex(p->object.sha1));
358 p->parents = NULL;
359 }
360 /* fallthrough */
361 case REV_TREE_DIFFERENT:
362 tree_changed = 1;
363 pp = &parent->next;
364 continue;
365 }
366 die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
367 }
368 if (tree_changed && !tree_same)
369 commit->object.flags |= TREECHANGE;
370 }
371
372 static int add_parents_to_list(struct rev_info *revs, struct commit *commit, struct commit_list **list)
373 {
374 struct commit_list *parent = commit->parents;
375 unsigned left_flag;
376 int add, rest;
377
378 if (commit->object.flags & ADDED)
379 return 0;
380 commit->object.flags |= ADDED;
381
382 /*
383 * If the commit is uninteresting, don't try to
384 * prune parents - we want the maximal uninteresting
385 * set.
386 *
387 * Normally we haven't parsed the parent
388 * yet, so we won't have a parent of a parent
389 * here. However, it may turn out that we've
390 * reached this commit some other way (where it
391 * wasn't uninteresting), in which case we need
392 * to mark its parents recursively too..
393 */
394 if (commit->object.flags & UNINTERESTING) {
395 while (parent) {
396 struct commit *p = parent->item;
397 parent = parent->next;
398 if (parse_commit(p) < 0)
399 return -1;
400 p->object.flags |= UNINTERESTING;
401 if (p->parents)
402 mark_parents_uninteresting(p);
403 if (p->object.flags & SEEN)
404 continue;
405 p->object.flags |= SEEN;
406 insert_by_date(p, list);
407 }
408 return 0;
409 }
410
411 /*
412 * Ok, the commit wasn't uninteresting. Try to
413 * simplify the commit history and find the parent
414 * that has no differences in the path set if one exists.
415 */
416 if (revs->prune_fn)
417 revs->prune_fn(revs, commit);
418
419 if (revs->no_walk)
420 return 0;
421
422 left_flag = (commit->object.flags & SYMMETRIC_LEFT);
423
424 rest = !revs->first_parent_only;
425 for (parent = commit->parents, add = 1; parent; add = rest) {
426 struct commit *p = parent->item;
427
428 parent = parent->next;
429 if (parse_commit(p) < 0)
430 return -1;
431 p->object.flags |= left_flag;
432 if (p->object.flags & SEEN)
433 continue;
434 p->object.flags |= SEEN;
435 if (add)
436 insert_by_date(p, list);
437 }
438 return 0;
439 }
440
441 static void cherry_pick_list(struct commit_list *list, struct rev_info *revs)
442 {
443 struct commit_list *p;
444 int left_count = 0, right_count = 0;
445 int left_first;
446 struct patch_ids ids;
447
448 /* First count the commits on the left and on the right */
449 for (p = list; p; p = p->next) {
450 struct commit *commit = p->item;
451 unsigned flags = commit->object.flags;
452 if (flags & BOUNDARY)
453 ;
454 else if (flags & SYMMETRIC_LEFT)
455 left_count++;
456 else
457 right_count++;
458 }
459
460 left_first = left_count < right_count;
461 init_patch_ids(&ids);
462 if (revs->diffopt.nr_paths) {
463 ids.diffopts.nr_paths = revs->diffopt.nr_paths;
464 ids.diffopts.paths = revs->diffopt.paths;
465 ids.diffopts.pathlens = revs->diffopt.pathlens;
466 }
467
468 /* Compute patch-ids for one side */
469 for (p = list; p; p = p->next) {
470 struct commit *commit = p->item;
471 unsigned flags = commit->object.flags;
472
473 if (flags & BOUNDARY)
474 continue;
475 /*
476 * If we have fewer left, left_first is set and we omit
477 * commits on the right branch in this loop. If we have
478 * fewer right, we skip the left ones.
479 */
480 if (left_first != !!(flags & SYMMETRIC_LEFT))
481 continue;
482 commit->util = add_commit_patch_id(commit, &ids);
483 }
484
485 /* Check the other side */
486 for (p = list; p; p = p->next) {
487 struct commit *commit = p->item;
488 struct patch_id *id;
489 unsigned flags = commit->object.flags;
490
491 if (flags & BOUNDARY)
492 continue;
493 /*
494 * If we have fewer left, left_first is set and we omit
495 * commits on the left branch in this loop.
496 */
497 if (left_first == !!(flags & SYMMETRIC_LEFT))
498 continue;
499
500 /*
501 * Have we seen the same patch id?
502 */
503 id = has_commit_patch_id(commit, &ids);
504 if (!id)
505 continue;
506 id->seen = 1;
507 commit->object.flags |= SHOWN;
508 }
509
510 /* Now check the original side for seen ones */
511 for (p = list; p; p = p->next) {
512 struct commit *commit = p->item;
513 struct patch_id *ent;
514
515 ent = commit->util;
516 if (!ent)
517 continue;
518 if (ent->seen)
519 commit->object.flags |= SHOWN;
520 commit->util = NULL;
521 }
522
523 free_patch_ids(&ids);
524 }
525
526 static int limit_list(struct rev_info *revs)
527 {
528 struct commit_list *list = revs->commits;
529 struct commit_list *newlist = NULL;
530 struct commit_list **p = &newlist;
531
532 while (list) {
533 struct commit_list *entry = list;
534 struct commit *commit = list->item;
535 struct object *obj = &commit->object;
536
537 list = list->next;
538 free(entry);
539
540 if (revs->max_age != -1 && (commit->date < revs->max_age))
541 obj->flags |= UNINTERESTING;
542 if (add_parents_to_list(revs, commit, &list) < 0)
543 return -1;
544 if (obj->flags & UNINTERESTING) {
545 mark_parents_uninteresting(commit);
546 if (everybody_uninteresting(list))
547 break;
548 continue;
549 }
550 if (revs->min_age != -1 && (commit->date > revs->min_age))
551 continue;
552 p = &commit_list_insert(commit, p)->next;
553 }
554 if (revs->cherry_pick)
555 cherry_pick_list(newlist, revs);
556
557 revs->commits = newlist;
558 return 0;
559 }
560
561 struct all_refs_cb {
562 int all_flags;
563 int warned_bad_reflog;
564 struct rev_info *all_revs;
565 const char *name_for_errormsg;
566 };
567
568 static int handle_one_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
569 {
570 struct all_refs_cb *cb = cb_data;
571 struct object *object = get_reference(cb->all_revs, path, sha1,
572 cb->all_flags);
573 add_pending_object(cb->all_revs, object, path);
574 return 0;
575 }
576
577 static void handle_all(struct rev_info *revs, unsigned flags)
578 {
579 struct all_refs_cb cb;
580 cb.all_revs = revs;
581 cb.all_flags = flags;
582 for_each_ref(handle_one_ref, &cb);
583 }
584
585 static void handle_one_reflog_commit(unsigned char *sha1, void *cb_data)
586 {
587 struct all_refs_cb *cb = cb_data;
588 if (!is_null_sha1(sha1)) {
589 struct object *o = parse_object(sha1);
590 if (o) {
591 o->flags |= cb->all_flags;
592 add_pending_object(cb->all_revs, o, "");
593 }
594 else if (!cb->warned_bad_reflog) {
595 warning("reflog of '%s' references pruned commits",
596 cb->name_for_errormsg);
597 cb->warned_bad_reflog = 1;
598 }
599 }
600 }
601
602 static int handle_one_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
603 const char *email, unsigned long timestamp, int tz,
604 const char *message, void *cb_data)
605 {
606 handle_one_reflog_commit(osha1, cb_data);
607 handle_one_reflog_commit(nsha1, cb_data);
608 return 0;
609 }
610
611 static int handle_one_reflog(const char *path, const unsigned char *sha1, int flag, void *cb_data)
612 {
613 struct all_refs_cb *cb = cb_data;
614 cb->warned_bad_reflog = 0;
615 cb->name_for_errormsg = path;
616 for_each_reflog_ent(path, handle_one_reflog_ent, cb_data);
617 return 0;
618 }
619
620 static void handle_reflog(struct rev_info *revs, unsigned flags)
621 {
622 struct all_refs_cb cb;
623 cb.all_revs = revs;
624 cb.all_flags = flags;
625 for_each_reflog(handle_one_reflog, &cb);
626 }
627
628 static int add_parents_only(struct rev_info *revs, const char *arg, int flags)
629 {
630 unsigned char sha1[20];
631 struct object *it;
632 struct commit *commit;
633 struct commit_list *parents;
634
635 if (*arg == '^') {
636 flags ^= UNINTERESTING;
637 arg++;
638 }
639 if (get_sha1(arg, sha1))
640 return 0;
641 while (1) {
642 it = get_reference(revs, arg, sha1, 0);
643 if (it->type != OBJ_TAG)
644 break;
645 hashcpy(sha1, ((struct tag*)it)->tagged->sha1);
646 }
647 if (it->type != OBJ_COMMIT)
648 return 0;
649 commit = (struct commit *)it;
650 for (parents = commit->parents; parents; parents = parents->next) {
651 it = &parents->item->object;
652 it->flags |= flags;
653 add_pending_object(revs, it, arg);
654 }
655 return 1;
656 }
657
658 void init_revisions(struct rev_info *revs, const char *prefix)
659 {
660 memset(revs, 0, sizeof(*revs));
661
662 revs->abbrev = DEFAULT_ABBREV;
663 revs->ignore_merges = 1;
664 revs->simplify_history = 1;
665 revs->pruning.recursive = 1;
666 revs->pruning.quiet = 1;
667 revs->pruning.add_remove = file_add_remove;
668 revs->pruning.change = file_change;
669 revs->lifo = 1;
670 revs->dense = 1;
671 revs->prefix = prefix;
672 revs->max_age = -1;
673 revs->min_age = -1;
674 revs->skip_count = -1;
675 revs->max_count = -1;
676
677 revs->prune_fn = NULL;
678 revs->prune_data = NULL;
679
680 revs->topo_setter = topo_sort_default_setter;
681 revs->topo_getter = topo_sort_default_getter;
682
683 revs->commit_format = CMIT_FMT_DEFAULT;
684
685 diff_setup(&revs->diffopt);
686 }
687
688 static void add_pending_commit_list(struct rev_info *revs,
689 struct commit_list *commit_list,
690 unsigned int flags)
691 {
692 while (commit_list) {
693 struct object *object = &commit_list->item->object;
694 object->flags |= flags;
695 add_pending_object(revs, object, sha1_to_hex(object->sha1));
696 commit_list = commit_list->next;
697 }
698 }
699
700 static void prepare_show_merge(struct rev_info *revs)
701 {
702 struct commit_list *bases;
703 struct commit *head, *other;
704 unsigned char sha1[20];
705 const char **prune = NULL;
706 int i, prune_num = 1; /* counting terminating NULL */
707
708 if (get_sha1("HEAD", sha1) || !(head = lookup_commit(sha1)))
709 die("--merge without HEAD?");
710 if (get_sha1("MERGE_HEAD", sha1) || !(other = lookup_commit(sha1)))
711 die("--merge without MERGE_HEAD?");
712 add_pending_object(revs, &head->object, "HEAD");
713 add_pending_object(revs, &other->object, "MERGE_HEAD");
714 bases = get_merge_bases(head, other, 1);
715 while (bases) {
716 struct commit *it = bases->item;
717 struct commit_list *n = bases->next;
718 free(bases);
719 bases = n;
720 it->object.flags |= UNINTERESTING;
721 add_pending_object(revs, &it->object, "(merge-base)");
722 }
723
724 if (!active_nr)
725 read_cache();
726 for (i = 0; i < active_nr; i++) {
727 struct cache_entry *ce = active_cache[i];
728 if (!ce_stage(ce))
729 continue;
730 if (ce_path_match(ce, revs->prune_data)) {
731 prune_num++;
732 prune = xrealloc(prune, sizeof(*prune) * prune_num);
733 prune[prune_num-2] = ce->name;
734 prune[prune_num-1] = NULL;
735 }
736 while ((i+1 < active_nr) &&
737 ce_same_name(ce, active_cache[i+1]))
738 i++;
739 }
740 revs->prune_data = prune;
741 }
742
743 int handle_revision_arg(const char *arg, struct rev_info *revs,
744 int flags,
745 int cant_be_filename)
746 {
747 unsigned mode;
748 char *dotdot;
749 struct object *object;
750 unsigned char sha1[20];
751 int local_flags;
752
753 dotdot = strstr(arg, "..");
754 if (dotdot) {
755 unsigned char from_sha1[20];
756 const char *next = dotdot + 2;
757 const char *this = arg;
758 int symmetric = *next == '.';
759 unsigned int flags_exclude = flags ^ UNINTERESTING;
760
761 *dotdot = 0;
762 next += symmetric;
763
764 if (!*next)
765 next = "HEAD";
766 if (dotdot == arg)
767 this = "HEAD";
768 if (!get_sha1(this, from_sha1) &&
769 !get_sha1(next, sha1)) {
770 struct commit *a, *b;
771 struct commit_list *exclude;
772
773 a = lookup_commit_reference(from_sha1);
774 b = lookup_commit_reference(sha1);
775 if (!a || !b) {
776 die(symmetric ?
777 "Invalid symmetric difference expression %s...%s" :
778 "Invalid revision range %s..%s",
779 arg, next);
780 }
781
782 if (!cant_be_filename) {
783 *dotdot = '.';
784 verify_non_filename(revs->prefix, arg);
785 }
786
787 if (symmetric) {
788 exclude = get_merge_bases(a, b, 1);
789 add_pending_commit_list(revs, exclude,
790 flags_exclude);
791 free_commit_list(exclude);
792 a->object.flags |= flags | SYMMETRIC_LEFT;
793 } else
794 a->object.flags |= flags_exclude;
795 b->object.flags |= flags;
796 add_pending_object(revs, &a->object, this);
797 add_pending_object(revs, &b->object, next);
798 return 0;
799 }
800 *dotdot = '.';
801 }
802 dotdot = strstr(arg, "^@");
803 if (dotdot && !dotdot[2]) {
804 *dotdot = 0;
805 if (add_parents_only(revs, arg, flags))
806 return 0;
807 *dotdot = '^';
808 }
809 dotdot = strstr(arg, "^!");
810 if (dotdot && !dotdot[2]) {
811 *dotdot = 0;
812 if (!add_parents_only(revs, arg, flags ^ UNINTERESTING))
813 *dotdot = '^';
814 }
815
816 local_flags = 0;
817 if (*arg == '^') {
818 local_flags = UNINTERESTING;
819 arg++;
820 }
821 if (get_sha1_with_mode(arg, sha1, &mode))
822 return -1;
823 if (!cant_be_filename)
824 verify_non_filename(revs->prefix, arg);
825 object = get_reference(revs, arg, sha1, flags ^ local_flags);
826 add_pending_object_with_mode(revs, object, arg, mode);
827 return 0;
828 }
829
830 static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
831 {
832 if (!revs->grep_filter) {
833 struct grep_opt *opt = xcalloc(1, sizeof(*opt));
834 opt->status_only = 1;
835 opt->pattern_tail = &(opt->pattern_list);
836 opt->regflags = REG_NEWLINE;
837 revs->grep_filter = opt;
838 }
839 append_grep_pattern(revs->grep_filter, ptn,
840 "command line", 0, what);
841 }
842
843 static void add_header_grep(struct rev_info *revs, const char *field, const char *pattern)
844 {
845 char *pat;
846 const char *prefix;
847 int patlen, fldlen;
848
849 fldlen = strlen(field);
850 patlen = strlen(pattern);
851 pat = xmalloc(patlen + fldlen + 10);
852 prefix = ".*";
853 if (*pattern == '^') {
854 prefix = "";
855 pattern++;
856 }
857 sprintf(pat, "^%s %s%s", field, prefix, pattern);
858 add_grep(revs, pat, GREP_PATTERN_HEAD);
859 }
860
861 static void add_message_grep(struct rev_info *revs, const char *pattern)
862 {
863 add_grep(revs, pattern, GREP_PATTERN_BODY);
864 }
865
866 static void add_ignore_packed(struct rev_info *revs, const char *name)
867 {
868 int num = ++revs->num_ignore_packed;
869
870 revs->ignore_packed = xrealloc(revs->ignore_packed,
871 sizeof(const char **) * (num + 1));
872 revs->ignore_packed[num-1] = name;
873 revs->ignore_packed[num] = NULL;
874 }
875
876 /*
877 * Parse revision information, filling in the "rev_info" structure,
878 * and removing the used arguments from the argument list.
879 *
880 * Returns the number of arguments left that weren't recognized
881 * (which are also moved to the head of the argument list)
882 */
883 int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def)
884 {
885 int i, flags, seen_dashdash, show_merge;
886 const char **unrecognized = argv + 1;
887 int left = 1;
888 int all_match = 0;
889 int regflags = 0;
890
891 /* First, search for "--" */
892 seen_dashdash = 0;
893 for (i = 1; i < argc; i++) {
894 const char *arg = argv[i];
895 if (strcmp(arg, "--"))
896 continue;
897 argv[i] = NULL;
898 argc = i;
899 if (argv[i + 1])
900 revs->prune_data = get_pathspec(revs->prefix, argv + i + 1);
901 seen_dashdash = 1;
902 break;
903 }
904
905 flags = show_merge = 0;
906 for (i = 1; i < argc; i++) {
907 const char *arg = argv[i];
908 if (*arg == '-') {
909 int opts;
910 if (!prefixcmp(arg, "--max-count=")) {
911 revs->max_count = atoi(arg + 12);
912 continue;
913 }
914 if (!prefixcmp(arg, "--skip=")) {
915 revs->skip_count = atoi(arg + 7);
916 continue;
917 }
918 /* accept -<digit>, like traditional "head" */
919 if ((*arg == '-') && isdigit(arg[1])) {
920 revs->max_count = atoi(arg + 1);
921 continue;
922 }
923 if (!strcmp(arg, "-n")) {
924 if (argc <= i + 1)
925 die("-n requires an argument");
926 revs->max_count = atoi(argv[++i]);
927 continue;
928 }
929 if (!prefixcmp(arg, "-n")) {
930 revs->max_count = atoi(arg + 2);
931 continue;
932 }
933 if (!prefixcmp(arg, "--max-age=")) {
934 revs->max_age = atoi(arg + 10);
935 continue;
936 }
937 if (!prefixcmp(arg, "--since=")) {
938 revs->max_age = approxidate(arg + 8);
939 continue;
940 }
941 if (!prefixcmp(arg, "--after=")) {
942 revs->max_age = approxidate(arg + 8);
943 continue;
944 }
945 if (!prefixcmp(arg, "--min-age=")) {
946 revs->min_age = atoi(arg + 10);
947 continue;
948 }
949 if (!prefixcmp(arg, "--before=")) {
950 revs->min_age = approxidate(arg + 9);
951 continue;
952 }
953 if (!prefixcmp(arg, "--until=")) {
954 revs->min_age = approxidate(arg + 8);
955 continue;
956 }
957 if (!strcmp(arg, "--all")) {
958 handle_all(revs, flags);
959 continue;
960 }
961 if (!strcmp(arg, "--first-parent")) {
962 revs->first_parent_only = 1;
963 continue;
964 }
965 if (!strcmp(arg, "--reflog")) {
966 handle_reflog(revs, flags);
967 continue;
968 }
969 if (!strcmp(arg, "-g") ||
970 !strcmp(arg, "--walk-reflogs")) {
971 init_reflog_walk(&revs->reflog_info);
972 continue;
973 }
974 if (!strcmp(arg, "--not")) {
975 flags ^= UNINTERESTING;
976 continue;
977 }
978 if (!strcmp(arg, "--default")) {
979 if (++i >= argc)
980 die("bad --default argument");
981 def = argv[i];
982 continue;
983 }
984 if (!strcmp(arg, "--merge")) {
985 show_merge = 1;
986 continue;
987 }
988 if (!strcmp(arg, "--topo-order")) {
989 revs->topo_order = 1;
990 continue;
991 }
992 if (!strcmp(arg, "--date-order")) {
993 revs->lifo = 0;
994 revs->topo_order = 1;
995 continue;
996 }
997 if (!strcmp(arg, "--parents")) {
998 revs->parents = 1;
999 continue;
1000 }
1001 if (!strcmp(arg, "--dense")) {
1002 revs->dense = 1;
1003 continue;
1004 }
1005 if (!strcmp(arg, "--sparse")) {
1006 revs->dense = 0;
1007 continue;
1008 }
1009 if (!strcmp(arg, "--remove-empty")) {
1010 revs->remove_empty_trees = 1;
1011 continue;
1012 }
1013 if (!strcmp(arg, "--no-merges")) {
1014 revs->no_merges = 1;
1015 continue;
1016 }
1017 if (!strcmp(arg, "--boundary")) {
1018 revs->boundary = 1;
1019 continue;
1020 }
1021 if (!strcmp(arg, "--left-right")) {
1022 revs->left_right = 1;
1023 continue;
1024 }
1025 if (!strcmp(arg, "--cherry-pick")) {
1026 revs->cherry_pick = 1;
1027 revs->limited = 1;
1028 continue;
1029 }
1030 if (!strcmp(arg, "--objects")) {
1031 revs->tag_objects = 1;
1032 revs->tree_objects = 1;
1033 revs->blob_objects = 1;
1034 continue;
1035 }
1036 if (!strcmp(arg, "--objects-edge")) {
1037 revs->tag_objects = 1;
1038 revs->tree_objects = 1;
1039 revs->blob_objects = 1;
1040 revs->edge_hint = 1;
1041 continue;
1042 }
1043 if (!strcmp(arg, "--unpacked")) {
1044 revs->unpacked = 1;
1045 free(revs->ignore_packed);
1046 revs->ignore_packed = NULL;
1047 revs->num_ignore_packed = 0;
1048 continue;
1049 }
1050 if (!prefixcmp(arg, "--unpacked=")) {
1051 revs->unpacked = 1;
1052 add_ignore_packed(revs, arg+11);
1053 continue;
1054 }
1055 if (!strcmp(arg, "-r")) {
1056 revs->diff = 1;
1057 revs->diffopt.recursive = 1;
1058 continue;
1059 }
1060 if (!strcmp(arg, "-t")) {
1061 revs->diff = 1;
1062 revs->diffopt.recursive = 1;
1063 revs->diffopt.tree_in_recursive = 1;
1064 continue;
1065 }
1066 if (!strcmp(arg, "-m")) {
1067 revs->ignore_merges = 0;
1068 continue;
1069 }
1070 if (!strcmp(arg, "-c")) {
1071 revs->diff = 1;
1072 revs->dense_combined_merges = 0;
1073 revs->combine_merges = 1;
1074 continue;
1075 }
1076 if (!strcmp(arg, "--cc")) {
1077 revs->diff = 1;
1078 revs->dense_combined_merges = 1;
1079 revs->combine_merges = 1;
1080 continue;
1081 }
1082 if (!strcmp(arg, "-v")) {
1083 revs->verbose_header = 1;
1084 continue;
1085 }
1086 if (!prefixcmp(arg, "--pretty")) {
1087 revs->verbose_header = 1;
1088 revs->commit_format = get_commit_format(arg+8);
1089 continue;
1090 }
1091 if (!strcmp(arg, "--root")) {
1092 revs->show_root_diff = 1;
1093 continue;
1094 }
1095 if (!strcmp(arg, "--no-commit-id")) {
1096 revs->no_commit_id = 1;
1097 continue;
1098 }
1099 if (!strcmp(arg, "--always")) {
1100 revs->always_show_header = 1;
1101 continue;
1102 }
1103 if (!strcmp(arg, "--no-abbrev")) {
1104 revs->abbrev = 0;
1105 continue;
1106 }
1107 if (!strcmp(arg, "--abbrev")) {
1108 revs->abbrev = DEFAULT_ABBREV;
1109 continue;
1110 }
1111 if (!prefixcmp(arg, "--abbrev=")) {
1112 revs->abbrev = strtoul(arg + 9, NULL, 10);
1113 if (revs->abbrev < MINIMUM_ABBREV)
1114 revs->abbrev = MINIMUM_ABBREV;
1115 else if (revs->abbrev > 40)
1116 revs->abbrev = 40;
1117 continue;
1118 }
1119 if (!strcmp(arg, "--abbrev-commit")) {
1120 revs->abbrev_commit = 1;
1121 continue;
1122 }
1123 if (!strcmp(arg, "--full-diff")) {
1124 revs->diff = 1;
1125 revs->full_diff = 1;
1126 continue;
1127 }
1128 if (!strcmp(arg, "--full-history")) {
1129 revs->simplify_history = 0;
1130 continue;
1131 }
1132 if (!strcmp(arg, "--relative-date")) {
1133 revs->date_mode = DATE_RELATIVE;
1134 continue;
1135 }
1136 if (!strncmp(arg, "--date=", 7)) {
1137 if (!strcmp(arg + 7, "relative"))
1138 revs->date_mode = DATE_RELATIVE;
1139 else if (!strcmp(arg + 7, "iso8601") ||
1140 !strcmp(arg + 7, "iso"))
1141 revs->date_mode = DATE_ISO8601;
1142 else if (!strcmp(arg + 7, "rfc2822") ||
1143 !strcmp(arg + 7, "rfc"))
1144 revs->date_mode = DATE_RFC2822;
1145 else if (!strcmp(arg + 7, "short"))
1146 revs->date_mode = DATE_SHORT;
1147 else if (!strcmp(arg + 7, "local"))
1148 revs->date_mode = DATE_LOCAL;
1149 else if (!strcmp(arg + 7, "default"))
1150 revs->date_mode = DATE_NORMAL;
1151 else
1152 die("unknown date format %s", arg);
1153 continue;
1154 }
1155 if (!strcmp(arg, "--log-size")) {
1156 revs->show_log_size = 1;
1157 continue;
1158 }
1159
1160 /*
1161 * Grepping the commit log
1162 */
1163 if (!prefixcmp(arg, "--author=")) {
1164 add_header_grep(revs, "author", arg+9);
1165 continue;
1166 }
1167 if (!prefixcmp(arg, "--committer=")) {
1168 add_header_grep(revs, "committer", arg+12);
1169 continue;
1170 }
1171 if (!prefixcmp(arg, "--grep=")) {
1172 add_message_grep(revs, arg+7);
1173 continue;
1174 }
1175 if (!strcmp(arg, "--extended-regexp") ||
1176 !strcmp(arg, "-E")) {
1177 regflags |= REG_EXTENDED;
1178 continue;
1179 }
1180 if (!strcmp(arg, "--regexp-ignore-case") ||
1181 !strcmp(arg, "-i")) {
1182 regflags |= REG_ICASE;
1183 continue;
1184 }
1185 if (!strcmp(arg, "--all-match")) {
1186 all_match = 1;
1187 continue;
1188 }
1189 if (!prefixcmp(arg, "--encoding=")) {
1190 arg += 11;
1191 if (strcmp(arg, "none"))
1192 git_log_output_encoding = xstrdup(arg);
1193 else
1194 git_log_output_encoding = "";
1195 continue;
1196 }
1197 if (!strcmp(arg, "--reverse")) {
1198 revs->reverse ^= 1;
1199 continue;
1200 }
1201 if (!strcmp(arg, "--no-walk")) {
1202 revs->no_walk = 1;
1203 continue;
1204 }
1205 if (!strcmp(arg, "--do-walk")) {
1206 revs->no_walk = 0;
1207 continue;
1208 }
1209
1210 opts = diff_opt_parse(&revs->diffopt, argv+i, argc-i);
1211 if (opts > 0) {
1212 i += opts - 1;
1213 continue;
1214 }
1215 *unrecognized++ = arg;
1216 left++;
1217 continue;
1218 }
1219
1220 if (handle_revision_arg(arg, revs, flags, seen_dashdash)) {
1221 int j;
1222 if (seen_dashdash || *arg == '^')
1223 die("bad revision '%s'", arg);
1224
1225 /* If we didn't have a "--":
1226 * (1) all filenames must exist;
1227 * (2) all rev-args must not be interpretable
1228 * as a valid filename.
1229 * but the latter we have checked in the main loop.
1230 */
1231 for (j = i; j < argc; j++)
1232 verify_filename(revs->prefix, argv[j]);
1233
1234 revs->prune_data = get_pathspec(revs->prefix,
1235 argv + i);
1236 break;
1237 }
1238 }
1239
1240 if (revs->grep_filter)
1241 revs->grep_filter->regflags |= regflags;
1242
1243 if (show_merge)
1244 prepare_show_merge(revs);
1245 if (def && !revs->pending.nr) {
1246 unsigned char sha1[20];
1247 struct object *object;
1248 unsigned mode;
1249 if (get_sha1_with_mode(def, sha1, &mode))
1250 die("bad default revision '%s'", def);
1251 object = get_reference(revs, def, sha1, 0);
1252 add_pending_object_with_mode(revs, object, def, mode);
1253 }
1254
1255 /* Did the user ask for any diff output? Run the diff! */
1256 if (revs->diffopt.output_format & ~DIFF_FORMAT_NO_OUTPUT)
1257 revs->diff = 1;
1258
1259 /* Pickaxe needs diffs */
1260 if (revs->diffopt.pickaxe)
1261 revs->diff = 1;
1262
1263 if (revs->topo_order)
1264 revs->limited = 1;
1265
1266 if (revs->prune_data) {
1267 diff_tree_setup_paths(revs->prune_data, &revs->pruning);
1268 /* Can't prune commits with rename following: the paths change.. */
1269 if (!revs->diffopt.follow_renames)
1270 revs->prune_fn = try_to_simplify_commit;
1271 if (!revs->full_diff)
1272 diff_tree_setup_paths(revs->prune_data, &revs->diffopt);
1273 }
1274 if (revs->combine_merges) {
1275 revs->ignore_merges = 0;
1276 if (revs->dense_combined_merges && !revs->diffopt.output_format)
1277 revs->diffopt.output_format = DIFF_FORMAT_PATCH;
1278 }
1279 revs->diffopt.abbrev = revs->abbrev;
1280 if (diff_setup_done(&revs->diffopt) < 0)
1281 die("diff_setup_done failed");
1282
1283 if (revs->grep_filter) {
1284 revs->grep_filter->all_match = all_match;
1285 compile_grep_patterns(revs->grep_filter);
1286 }
1287
1288 if (revs->reverse && revs->reflog_info)
1289 die("cannot combine --reverse with --walk-reflogs");
1290
1291 return left;
1292 }
1293
1294 int prepare_revision_walk(struct rev_info *revs)
1295 {
1296 int nr = revs->pending.nr;
1297 struct object_array_entry *e, *list;
1298
1299 e = list = revs->pending.objects;
1300 revs->pending.nr = 0;
1301 revs->pending.alloc = 0;
1302 revs->pending.objects = NULL;
1303 while (--nr >= 0) {
1304 struct commit *commit = handle_commit(revs, e->item, e->name);
1305 if (commit) {
1306 if (!(commit->object.flags & SEEN)) {
1307 commit->object.flags |= SEEN;
1308 insert_by_date(commit, &revs->commits);
1309 }
1310 }
1311 e++;
1312 }
1313 free(list);
1314
1315 if (revs->no_walk)
1316 return 0;
1317 if (revs->limited)
1318 if (limit_list(revs) < 0)
1319 return -1;
1320 if (revs->topo_order)
1321 sort_in_topological_order_fn(&revs->commits, revs->lifo,
1322 revs->topo_setter,
1323 revs->topo_getter);
1324 return 0;
1325 }
1326
1327 enum rewrite_result {
1328 rewrite_one_ok,
1329 rewrite_one_noparents,
1330 rewrite_one_error,
1331 };
1332
1333 static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp)
1334 {
1335 for (;;) {
1336 struct commit *p = *pp;
1337 if (!revs->limited)
1338 if (add_parents_to_list(revs, p, &revs->commits) < 0)
1339 return rewrite_one_error;
1340 if (p->parents && p->parents->next)
1341 return rewrite_one_ok;
1342 if (p->object.flags & (TREECHANGE | UNINTERESTING))
1343 return rewrite_one_ok;
1344 if (!p->parents)
1345 return rewrite_one_noparents;
1346 *pp = p->parents->item;
1347 }
1348 }
1349
1350 static void remove_duplicate_parents(struct commit *commit)
1351 {
1352 struct commit_list **pp, *p;
1353
1354 /* Examine existing parents while marking ones we have seen... */
1355 pp = &commit->parents;
1356 while ((p = *pp) != NULL) {
1357 struct commit *parent = p->item;
1358 if (parent->object.flags & TMP_MARK) {
1359 *pp = p->next;
1360 continue;
1361 }
1362 parent->object.flags |= TMP_MARK;
1363 pp = &p->next;
1364 }
1365 /* ... and clear the temporary mark */
1366 for (p = commit->parents; p; p = p->next)
1367 p->item->object.flags &= ~TMP_MARK;
1368 }
1369
1370 static int rewrite_parents(struct rev_info *revs, struct commit *commit)
1371 {
1372 struct commit_list **pp = &commit->parents;
1373 while (*pp) {
1374 struct commit_list *parent = *pp;
1375 switch (rewrite_one(revs, &parent->item)) {
1376 case rewrite_one_ok:
1377 break;
1378 case rewrite_one_noparents:
1379 *pp = parent->next;
1380 continue;
1381 case rewrite_one_error:
1382 return -1;
1383 }
1384 pp = &parent->next;
1385 }
1386 remove_duplicate_parents(commit);
1387 return 0;
1388 }
1389
1390 static int commit_match(struct commit *commit, struct rev_info *opt)
1391 {
1392 if (!opt->grep_filter)
1393 return 1;
1394 return grep_buffer(opt->grep_filter,
1395 NULL, /* we say nothing, not even filename */
1396 commit->buffer, strlen(commit->buffer));
1397 }
1398
1399 static struct commit *get_revision_1(struct rev_info *revs)
1400 {
1401 if (!revs->commits)
1402 return NULL;
1403
1404 do {
1405 struct commit_list *entry = revs->commits;
1406 struct commit *commit = entry->item;
1407
1408 revs->commits = entry->next;
1409 free(entry);
1410
1411 if (revs->reflog_info)
1412 fake_reflog_parent(revs->reflog_info, commit);
1413
1414 /*
1415 * If we haven't done the list limiting, we need to look at
1416 * the parents here. We also need to do the date-based limiting
1417 * that we'd otherwise have done in limit_list().
1418 */
1419 if (!revs->limited) {
1420 if (revs->max_age != -1 &&
1421 (commit->date < revs->max_age))
1422 continue;
1423 if (add_parents_to_list(revs, commit, &revs->commits) < 0)
1424 return NULL;
1425 }
1426 if (commit->object.flags & SHOWN)
1427 continue;
1428
1429 if (revs->unpacked && has_sha1_pack(commit->object.sha1,
1430 revs->ignore_packed))
1431 continue;
1432
1433 if (commit->object.flags & UNINTERESTING)
1434 continue;
1435 if (revs->min_age != -1 && (commit->date > revs->min_age))
1436 continue;
1437 if (revs->no_merges &&
1438 commit->parents && commit->parents->next)
1439 continue;
1440 if (!commit_match(commit, revs))
1441 continue;
1442 if (revs->prune_fn && revs->dense) {
1443 /* Commit without changes? */
1444 if (!(commit->object.flags & TREECHANGE)) {
1445 /* drop merges unless we want parenthood */
1446 if (!revs->parents)
1447 continue;
1448 /* non-merge - always ignore it */
1449 if (!commit->parents || !commit->parents->next)
1450 continue;
1451 }
1452 if (revs->parents && rewrite_parents(revs, commit) < 0)
1453 return NULL;
1454 }
1455 return commit;
1456 } while (revs->commits);
1457 return NULL;
1458 }
1459
1460 static void gc_boundary(struct object_array *array)
1461 {
1462 unsigned nr = array->nr;
1463 unsigned alloc = array->alloc;
1464 struct object_array_entry *objects = array->objects;
1465
1466 if (alloc <= nr) {
1467 unsigned i, j;
1468 for (i = j = 0; i < nr; i++) {
1469 if (objects[i].item->flags & SHOWN)
1470 continue;
1471 if (i != j)
1472 objects[j] = objects[i];
1473 j++;
1474 }
1475 for (i = j; i < nr; i++)
1476 objects[i].item = NULL;
1477 array->nr = j;
1478 }
1479 }
1480
1481 struct commit *get_revision(struct rev_info *revs)
1482 {
1483 struct commit *c = NULL;
1484 struct commit_list *l;
1485
1486 if (revs->boundary == 2) {
1487 unsigned i;
1488 struct object_array *array = &revs->boundary_commits;
1489 struct object_array_entry *objects = array->objects;
1490 for (i = 0; i < array->nr; i++) {
1491 c = (struct commit *)(objects[i].item);
1492 if (!c)
1493 continue;
1494 if (!(c->object.flags & CHILD_SHOWN))
1495 continue;
1496 if (!(c->object.flags & SHOWN))
1497 break;
1498 }
1499 if (array->nr <= i)
1500 return NULL;
1501
1502 c->object.flags |= SHOWN | BOUNDARY;
1503 return c;
1504 }
1505
1506 if (revs->reverse) {
1507 int limit = -1;
1508
1509 if (0 <= revs->max_count) {
1510 limit = revs->max_count;
1511 if (0 < revs->skip_count)
1512 limit += revs->skip_count;
1513 }
1514 l = NULL;
1515 while ((c = get_revision_1(revs))) {
1516 commit_list_insert(c, &l);
1517 if ((0 < limit) && !--limit)
1518 break;
1519 }
1520 revs->commits = l;
1521 revs->reverse = 0;
1522 revs->max_count = -1;
1523 c = NULL;
1524 }
1525
1526 /*
1527 * Now pick up what they want to give us
1528 */
1529 c = get_revision_1(revs);
1530 if (c) {
1531 while (0 < revs->skip_count) {
1532 revs->skip_count--;
1533 c = get_revision_1(revs);
1534 if (!c)
1535 break;
1536 }
1537 }
1538
1539 /*
1540 * Check the max_count.
1541 */
1542 switch (revs->max_count) {
1543 case -1:
1544 break;
1545 case 0:
1546 c = NULL;
1547 break;
1548 default:
1549 revs->max_count--;
1550 }
1551
1552 if (c)
1553 c->object.flags |= SHOWN;
1554
1555 if (!revs->boundary) {
1556 return c;
1557 }
1558
1559 if (!c) {
1560 /*
1561 * get_revision_1() runs out the commits, and
1562 * we are done computing the boundaries.
1563 * switch to boundary commits output mode.
1564 */
1565 revs->boundary = 2;
1566 return get_revision(revs);
1567 }
1568
1569 /*
1570 * boundary commits are the commits that are parents of the
1571 * ones we got from get_revision_1() but they themselves are
1572 * not returned from get_revision_1(). Before returning
1573 * 'c', we need to mark its parents that they could be boundaries.
1574 */
1575
1576 for (l = c->parents; l; l = l->next) {
1577 struct object *p;
1578 p = &(l->item->object);
1579 if (p->flags & (CHILD_SHOWN | SHOWN))
1580 continue;
1581 p->flags |= CHILD_SHOWN;
1582 gc_boundary(&revs->boundary_commits);
1583 add_object_array(p, NULL, &revs->boundary_commits);
1584 }
1585
1586 return c;
1587 }