gitweb: Change atom, rss actions to use parse_commits.
[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
11 static char *path_name(struct name_path *path, const char *name)
12 {
13         struct name_path *p;
14         char *n, *m;
15         int nlen = strlen(name);
16         int len = nlen + 1;
17
18         for (p = path; p; p = p->up) {
19                 if (p->elem_len)
20                         len += p->elem_len + 1;
21         }
22         n = xmalloc(len);
23         m = n + len - (nlen + 1);
24         strcpy(m, name);
25         for (p = path; p; p = p->up) {
26                 if (p->elem_len) {
27                         m -= p->elem_len + 1;
28                         memcpy(m, p->elem, p->elem_len);
29                         m[p->elem_len] = '/';
30                 }
31         }
32         return n;
33 }
34
35 void add_object(struct object *obj,
36                 struct object_array *p,
37                 struct name_path *path,
38                 const char *name)
39 {
40         add_object_array(obj, path_name(path, name), p);
41 }
42
43 static void mark_blob_uninteresting(struct blob *blob)
44 {
45         if (blob->object.flags & UNINTERESTING)
46                 return;
47         blob->object.flags |= UNINTERESTING;
48 }
49
50 void mark_tree_uninteresting(struct tree *tree)
51 {
52         struct tree_desc desc;
53         struct name_entry entry;
54         struct object *obj = &tree->object;
55
56         if (obj->flags & UNINTERESTING)
57                 return;
58         obj->flags |= UNINTERESTING;
59         if (!has_sha1_file(obj->sha1))
60                 return;
61         if (parse_tree(tree) < 0)
62                 die("bad tree %s", sha1_to_hex(obj->sha1));
63
64         desc.buf = tree->buffer;
65         desc.size = tree->size;
66         while (tree_entry(&desc, &entry)) {
67                 if (S_ISDIR(entry.mode))
68                         mark_tree_uninteresting(lookup_tree(entry.sha1));
69                 else
70                         mark_blob_uninteresting(lookup_blob(entry.sha1));
71         }
72
73         /*
74          * We don't care about the tree any more
75          * after it has been marked uninteresting.
76          */
77         free(tree->buffer);
78         tree->buffer = NULL;
79 }
80
81 void mark_parents_uninteresting(struct commit *commit)
82 {
83         struct commit_list *parents = commit->parents;
84
85         while (parents) {
86                 struct commit *commit = parents->item;
87                 if (!(commit->object.flags & UNINTERESTING)) {
88                         commit->object.flags |= UNINTERESTING;
89
90                         /*
91                          * Normally we haven't parsed the parent
92                          * yet, so we won't have a parent of a parent
93                          * here. However, it may turn out that we've
94                          * reached this commit some other way (where it
95                          * wasn't uninteresting), in which case we need
96                          * to mark its parents recursively too..
97                          */
98                         if (commit->parents)
99                                 mark_parents_uninteresting(commit);
100                 }
101
102                 /*
103                  * A missing commit is ok iff its parent is marked
104                  * uninteresting.
105                  *
106                  * We just mark such a thing parsed, so that when
107                  * it is popped next time around, we won't be trying
108                  * to parse it and get an error.
109                  */
110                 if (!has_sha1_file(commit->object.sha1))
111                         commit->object.parsed = 1;
112                 parents = parents->next;
113         }
114 }
115
116 void add_pending_object(struct rev_info *revs, struct object *obj, const char *name)
117 {
118         add_object_array(obj, name, &revs->pending);
119 }
120
121 static struct object *get_reference(struct rev_info *revs, const char *name, const unsigned char *sha1, unsigned int flags)
122 {
123         struct object *object;
124
125         object = parse_object(sha1);
126         if (!object)
127                 die("bad object %s", name);
128         object->flags |= flags;
129         return object;
130 }
131
132 static struct commit *handle_commit(struct rev_info *revs, struct object *object, const char *name)
133 {
134         unsigned long flags = object->flags;
135
136         /*
137          * Tag object? Look what it points to..
138          */
139         while (object->type == OBJ_TAG) {
140                 struct tag *tag = (struct tag *) object;
141                 if (revs->tag_objects && !(flags & UNINTERESTING))
142                         add_pending_object(revs, object, tag->tag);
143                 object = parse_object(tag->tagged->sha1);
144                 if (!object)
145                         die("bad object %s", sha1_to_hex(tag->tagged->sha1));
146         }
147
148         /*
149          * Commit object? Just return it, we'll do all the complex
150          * reachability crud.
151          */
152         if (object->type == OBJ_COMMIT) {
153                 struct commit *commit = (struct commit *)object;
154                 if (parse_commit(commit) < 0)
155                         die("unable to parse commit %s", name);
156                 if (flags & UNINTERESTING) {
157                         commit->object.flags |= UNINTERESTING;
158                         mark_parents_uninteresting(commit);
159                         revs->limited = 1;
160                 }
161                 return commit;
162         }
163
164         /*
165          * Tree object? Either mark it uniniteresting, or add it
166          * to the list of objects to look at later..
167          */
168         if (object->type == OBJ_TREE) {
169                 struct tree *tree = (struct tree *)object;
170                 if (!revs->tree_objects)
171                         return NULL;
172                 if (flags & UNINTERESTING) {
173                         mark_tree_uninteresting(tree);
174                         return NULL;
175                 }
176                 add_pending_object(revs, object, "");
177                 return NULL;
178         }
179
180         /*
181          * Blob object? You know the drill by now..
182          */
183         if (object->type == OBJ_BLOB) {
184                 struct blob *blob = (struct blob *)object;
185                 if (!revs->blob_objects)
186                         return NULL;
187                 if (flags & UNINTERESTING) {
188                         mark_blob_uninteresting(blob);
189                         return NULL;
190                 }
191                 add_pending_object(revs, object, "");
192                 return NULL;
193         }
194         die("%s is unknown object", name);
195 }
196
197 static int everybody_uninteresting(struct commit_list *orig)
198 {
199         struct commit_list *list = orig;
200         while (list) {
201                 struct commit *commit = list->item;
202                 list = list->next;
203                 if (commit->object.flags & UNINTERESTING)
204                         continue;
205                 return 0;
206         }
207         return 1;
208 }
209
210 static int tree_difference = REV_TREE_SAME;
211
212 static void file_add_remove(struct diff_options *options,
213                     int addremove, unsigned mode,
214                     const unsigned char *sha1,
215                     const char *base, const char *path)
216 {
217         int diff = REV_TREE_DIFFERENT;
218
219         /*
220          * Is it an add of a new file? It means that the old tree
221          * didn't have it at all, so we will turn "REV_TREE_SAME" ->
222          * "REV_TREE_NEW", but leave any "REV_TREE_DIFFERENT" alone
223          * (and if it already was "REV_TREE_NEW", we'll keep it
224          * "REV_TREE_NEW" of course).
225          */
226         if (addremove == '+') {
227                 diff = tree_difference;
228                 if (diff != REV_TREE_SAME)
229                         return;
230                 diff = REV_TREE_NEW;
231         }
232         tree_difference = diff;
233 }
234
235 static void file_change(struct diff_options *options,
236                  unsigned old_mode, unsigned new_mode,
237                  const unsigned char *old_sha1,
238                  const unsigned char *new_sha1,
239                  const char *base, const char *path)
240 {
241         tree_difference = REV_TREE_DIFFERENT;
242 }
243
244 int rev_compare_tree(struct rev_info *revs, struct tree *t1, struct tree *t2)
245 {
246         if (!t1)
247                 return REV_TREE_NEW;
248         if (!t2)
249                 return REV_TREE_DIFFERENT;
250         tree_difference = REV_TREE_SAME;
251         if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "",
252                            &revs->pruning) < 0)
253                 return REV_TREE_DIFFERENT;
254         return tree_difference;
255 }
256
257 int rev_same_tree_as_empty(struct rev_info *revs, struct tree *t1)
258 {
259         int retval;
260         void *tree;
261         struct tree_desc empty, real;
262
263         if (!t1)
264                 return 0;
265
266         tree = read_object_with_reference(t1->object.sha1, tree_type, &real.size, NULL);
267         if (!tree)
268                 return 0;
269         real.buf = tree;
270
271         empty.buf = "";
272         empty.size = 0;
273
274         tree_difference = 0;
275         retval = diff_tree(&empty, &real, "", &revs->pruning);
276         free(tree);
277
278         return retval >= 0 && !tree_difference;
279 }
280
281 static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
282 {
283         struct commit_list **pp, *parent;
284         int tree_changed = 0, tree_same = 0;
285
286         if (!commit->tree)
287                 return;
288
289         if (!commit->parents) {
290                 if (!rev_same_tree_as_empty(revs, commit->tree))
291                         commit->object.flags |= TREECHANGE;
292                 return;
293         }
294
295         pp = &commit->parents;
296         while ((parent = *pp) != NULL) {
297                 struct commit *p = parent->item;
298
299                 parse_commit(p);
300                 switch (rev_compare_tree(revs, p->tree, commit->tree)) {
301                 case REV_TREE_SAME:
302                         tree_same = 1;
303                         if (!revs->simplify_history || (p->object.flags & UNINTERESTING)) {
304                                 /* Even if a merge with an uninteresting
305                                  * side branch brought the entire change
306                                  * we are interested in, we do not want
307                                  * to lose the other branches of this
308                                  * merge, so we just keep going.
309                                  */
310                                 pp = &parent->next;
311                                 continue;
312                         }
313                         parent->next = NULL;
314                         commit->parents = parent;
315                         return;
316
317                 case REV_TREE_NEW:
318                         if (revs->remove_empty_trees &&
319                             rev_same_tree_as_empty(revs, p->tree)) {
320                                 /* We are adding all the specified
321                                  * paths from this parent, so the
322                                  * history beyond this parent is not
323                                  * interesting.  Remove its parents
324                                  * (they are grandparents for us).
325                                  * IOW, we pretend this parent is a
326                                  * "root" commit.
327                                  */
328                                 parse_commit(p);
329                                 p->parents = NULL;
330                         }
331                 /* fallthrough */
332                 case REV_TREE_DIFFERENT:
333                         tree_changed = 1;
334                         pp = &parent->next;
335                         continue;
336                 }
337                 die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
338         }
339         if (tree_changed && !tree_same)
340                 commit->object.flags |= TREECHANGE;
341 }
342
343 static void add_parents_to_list(struct rev_info *revs, struct commit *commit, struct commit_list **list)
344 {
345         struct commit_list *parent = commit->parents;
346         unsigned left_flag;
347
348         if (commit->object.flags & ADDED)
349                 return;
350         commit->object.flags |= ADDED;
351
352         /*
353          * If the commit is uninteresting, don't try to
354          * prune parents - we want the maximal uninteresting
355          * set.
356          *
357          * Normally we haven't parsed the parent
358          * yet, so we won't have a parent of a parent
359          * here. However, it may turn out that we've
360          * reached this commit some other way (where it
361          * wasn't uninteresting), in which case we need
362          * to mark its parents recursively too..
363          */
364         if (commit->object.flags & UNINTERESTING) {
365                 while (parent) {
366                         struct commit *p = parent->item;
367                         parent = parent->next;
368                         parse_commit(p);
369                         p->object.flags |= UNINTERESTING;
370                         if (p->parents)
371                                 mark_parents_uninteresting(p);
372                         if (p->object.flags & SEEN)
373                                 continue;
374                         p->object.flags |= SEEN;
375                         insert_by_date(p, list);
376                 }
377                 return;
378         }
379
380         /*
381          * Ok, the commit wasn't uninteresting. Try to
382          * simplify the commit history and find the parent
383          * that has no differences in the path set if one exists.
384          */
385         if (revs->prune_fn)
386                 revs->prune_fn(revs, commit);
387
388         if (revs->no_walk)
389                 return;
390
391         left_flag = (commit->object.flags & SYMMETRIC_LEFT);
392         parent = commit->parents;
393         while (parent) {
394                 struct commit *p = parent->item;
395
396                 parent = parent->next;
397
398                 parse_commit(p);
399                 p->object.flags |= left_flag;
400                 if (p->object.flags & SEEN)
401                         continue;
402                 p->object.flags |= SEEN;
403                 insert_by_date(p, list);
404         }
405 }
406
407 static void limit_list(struct rev_info *revs)
408 {
409         struct commit_list *list = revs->commits;
410         struct commit_list *newlist = NULL;
411         struct commit_list **p = &newlist;
412
413         while (list) {
414                 struct commit_list *entry = list;
415                 struct commit *commit = list->item;
416                 struct object *obj = &commit->object;
417
418                 list = list->next;
419                 free(entry);
420
421                 if (revs->max_age != -1 && (commit->date < revs->max_age))
422                         obj->flags |= UNINTERESTING;
423                 add_parents_to_list(revs, commit, &list);
424                 if (obj->flags & UNINTERESTING) {
425                         mark_parents_uninteresting(commit);
426                         if (everybody_uninteresting(list))
427                                 break;
428                         continue;
429                 }
430                 if (revs->min_age != -1 && (commit->date > revs->min_age))
431                         continue;
432                 p = &commit_list_insert(commit, p)->next;
433         }
434         if (revs->boundary) {
435                 /* mark the ones that are on the result list first */
436                 for (list = newlist; list; list = list->next) {
437                         struct commit *commit = list->item;
438                         commit->object.flags |= TMP_MARK;
439                 }
440                 for (list = newlist; list; list = list->next) {
441                         struct commit *commit = list->item;
442                         struct object *obj = &commit->object;
443                         struct commit_list *parent;
444                         if (obj->flags & UNINTERESTING)
445                                 continue;
446                         for (parent = commit->parents;
447                              parent;
448                              parent = parent->next) {
449                                 struct commit *pcommit = parent->item;
450                                 if (!(pcommit->object.flags & UNINTERESTING))
451                                         continue;
452                                 pcommit->object.flags |= BOUNDARY;
453                                 if (pcommit->object.flags & TMP_MARK)
454                                         continue;
455                                 pcommit->object.flags |= TMP_MARK;
456                                 p = &commit_list_insert(pcommit, p)->next;
457                         }
458                 }
459                 for (list = newlist; list; list = list->next) {
460                         struct commit *commit = list->item;
461                         commit->object.flags &= ~TMP_MARK;
462                 }
463         }
464         revs->commits = newlist;
465 }
466
467 static int all_flags;
468 static struct rev_info *all_revs;
469
470 static int handle_one_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
471 {
472         struct object *object = get_reference(all_revs, path, sha1, all_flags);
473         add_pending_object(all_revs, object, "");
474         return 0;
475 }
476
477 static void handle_all(struct rev_info *revs, unsigned flags)
478 {
479         all_revs = revs;
480         all_flags = flags;
481         for_each_ref(handle_one_ref, NULL);
482 }
483
484 static int add_parents_only(struct rev_info *revs, const char *arg, int flags)
485 {
486         unsigned char sha1[20];
487         struct object *it;
488         struct commit *commit;
489         struct commit_list *parents;
490
491         if (*arg == '^') {
492                 flags ^= UNINTERESTING;
493                 arg++;
494         }
495         if (get_sha1(arg, sha1))
496                 return 0;
497         while (1) {
498                 it = get_reference(revs, arg, sha1, 0);
499                 if (it->type != OBJ_TAG)
500                         break;
501                 hashcpy(sha1, ((struct tag*)it)->tagged->sha1);
502         }
503         if (it->type != OBJ_COMMIT)
504                 return 0;
505         commit = (struct commit *)it;
506         for (parents = commit->parents; parents; parents = parents->next) {
507                 it = &parents->item->object;
508                 it->flags |= flags;
509                 add_pending_object(revs, it, arg);
510         }
511         return 1;
512 }
513
514 void init_revisions(struct rev_info *revs, const char *prefix)
515 {
516         memset(revs, 0, sizeof(*revs));
517
518         revs->abbrev = DEFAULT_ABBREV;
519         revs->ignore_merges = 1;
520         revs->simplify_history = 1;
521         revs->pruning.recursive = 1;
522         revs->pruning.add_remove = file_add_remove;
523         revs->pruning.change = file_change;
524         revs->lifo = 1;
525         revs->dense = 1;
526         revs->prefix = prefix;
527         revs->max_age = -1;
528         revs->min_age = -1;
529         revs->skip_count = -1;
530         revs->max_count = -1;
531
532         revs->prune_fn = NULL;
533         revs->prune_data = NULL;
534
535         revs->topo_setter = topo_sort_default_setter;
536         revs->topo_getter = topo_sort_default_getter;
537
538         revs->commit_format = CMIT_FMT_DEFAULT;
539
540         diff_setup(&revs->diffopt);
541 }
542
543 static void add_pending_commit_list(struct rev_info *revs,
544                                     struct commit_list *commit_list,
545                                     unsigned int flags)
546 {
547         while (commit_list) {
548                 struct object *object = &commit_list->item->object;
549                 object->flags |= flags;
550                 add_pending_object(revs, object, sha1_to_hex(object->sha1));
551                 commit_list = commit_list->next;
552         }
553 }
554
555 static void prepare_show_merge(struct rev_info *revs)
556 {
557         struct commit_list *bases;
558         struct commit *head, *other;
559         unsigned char sha1[20];
560         const char **prune = NULL;
561         int i, prune_num = 1; /* counting terminating NULL */
562
563         if (get_sha1("HEAD", sha1) || !(head = lookup_commit(sha1)))
564                 die("--merge without HEAD?");
565         if (get_sha1("MERGE_HEAD", sha1) || !(other = lookup_commit(sha1)))
566                 die("--merge without MERGE_HEAD?");
567         add_pending_object(revs, &head->object, "HEAD");
568         add_pending_object(revs, &other->object, "MERGE_HEAD");
569         bases = get_merge_bases(head, other, 1);
570         while (bases) {
571                 struct commit *it = bases->item;
572                 struct commit_list *n = bases->next;
573                 free(bases);
574                 bases = n;
575                 it->object.flags |= UNINTERESTING;
576                 add_pending_object(revs, &it->object, "(merge-base)");
577         }
578
579         if (!active_nr)
580                 read_cache();
581         for (i = 0; i < active_nr; i++) {
582                 struct cache_entry *ce = active_cache[i];
583                 if (!ce_stage(ce))
584                         continue;
585                 if (ce_path_match(ce, revs->prune_data)) {
586                         prune_num++;
587                         prune = xrealloc(prune, sizeof(*prune) * prune_num);
588                         prune[prune_num-2] = ce->name;
589                         prune[prune_num-1] = NULL;
590                 }
591                 while ((i+1 < active_nr) &&
592                        ce_same_name(ce, active_cache[i+1]))
593                         i++;
594         }
595         revs->prune_data = prune;
596 }
597
598 int handle_revision_arg(const char *arg, struct rev_info *revs,
599                         int flags,
600                         int cant_be_filename)
601 {
602         char *dotdot;
603         struct object *object;
604         unsigned char sha1[20];
605         int local_flags;
606
607         dotdot = strstr(arg, "..");
608         if (dotdot) {
609                 unsigned char from_sha1[20];
610                 const char *next = dotdot + 2;
611                 const char *this = arg;
612                 int symmetric = *next == '.';
613                 unsigned int flags_exclude = flags ^ UNINTERESTING;
614
615                 *dotdot = 0;
616                 next += symmetric;
617
618                 if (!*next)
619                         next = "HEAD";
620                 if (dotdot == arg)
621                         this = "HEAD";
622                 if (!get_sha1(this, from_sha1) &&
623                     !get_sha1(next, sha1)) {
624                         struct commit *a, *b;
625                         struct commit_list *exclude;
626
627                         a = lookup_commit_reference(from_sha1);
628                         b = lookup_commit_reference(sha1);
629                         if (!a || !b) {
630                                 die(symmetric ?
631                                     "Invalid symmetric difference expression %s...%s" :
632                                     "Invalid revision range %s..%s",
633                                     arg, next);
634                         }
635
636                         if (!cant_be_filename) {
637                                 *dotdot = '.';
638                                 verify_non_filename(revs->prefix, arg);
639                         }
640
641                         if (symmetric) {
642                                 exclude = get_merge_bases(a, b, 1);
643                                 add_pending_commit_list(revs, exclude,
644                                                         flags_exclude);
645                                 free_commit_list(exclude);
646                                 a->object.flags |= flags | SYMMETRIC_LEFT;
647                         } else
648                                 a->object.flags |= flags_exclude;
649                         b->object.flags |= flags;
650                         add_pending_object(revs, &a->object, this);
651                         add_pending_object(revs, &b->object, next);
652                         return 0;
653                 }
654                 *dotdot = '.';
655         }
656         dotdot = strstr(arg, "^@");
657         if (dotdot && !dotdot[2]) {
658                 *dotdot = 0;
659                 if (add_parents_only(revs, arg, flags))
660                         return 0;
661                 *dotdot = '^';
662         }
663         dotdot = strstr(arg, "^!");
664         if (dotdot && !dotdot[2]) {
665                 *dotdot = 0;
666                 if (!add_parents_only(revs, arg, flags ^ UNINTERESTING))
667                         *dotdot = '^';
668         }
669
670         local_flags = 0;
671         if (*arg == '^') {
672                 local_flags = UNINTERESTING;
673                 arg++;
674         }
675         if (get_sha1(arg, sha1))
676                 return -1;
677         if (!cant_be_filename)
678                 verify_non_filename(revs->prefix, arg);
679         object = get_reference(revs, arg, sha1, flags ^ local_flags);
680         add_pending_object(revs, object, arg);
681         return 0;
682 }
683
684 static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
685 {
686         if (!revs->grep_filter) {
687                 struct grep_opt *opt = xcalloc(1, sizeof(*opt));
688                 opt->status_only = 1;
689                 opt->pattern_tail = &(opt->pattern_list);
690                 opt->regflags = REG_NEWLINE;
691                 revs->grep_filter = opt;
692         }
693         append_grep_pattern(revs->grep_filter, ptn,
694                             "command line", 0, what);
695 }
696
697 static void add_header_grep(struct rev_info *revs, const char *field, const char *pattern)
698 {
699         char *pat;
700         const char *prefix;
701         int patlen, fldlen;
702
703         fldlen = strlen(field);
704         patlen = strlen(pattern);
705         pat = xmalloc(patlen + fldlen + 10);
706         prefix = ".*";
707         if (*pattern == '^') {
708                 prefix = "";
709                 pattern++;
710         }
711         sprintf(pat, "^%s %s%s", field, prefix, pattern);
712         add_grep(revs, pat, GREP_PATTERN_HEAD);
713 }
714
715 static void add_message_grep(struct rev_info *revs, const char *pattern)
716 {
717         add_grep(revs, pattern, GREP_PATTERN_BODY);
718 }
719
720 static void add_ignore_packed(struct rev_info *revs, const char *name)
721 {
722         int num = ++revs->num_ignore_packed;
723
724         revs->ignore_packed = xrealloc(revs->ignore_packed,
725                                        sizeof(const char **) * (num + 1));
726         revs->ignore_packed[num-1] = name;
727         revs->ignore_packed[num] = NULL;
728 }
729
730 /*
731  * Parse revision information, filling in the "rev_info" structure,
732  * and removing the used arguments from the argument list.
733  *
734  * Returns the number of arguments left that weren't recognized
735  * (which are also moved to the head of the argument list)
736  */
737 int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def)
738 {
739         int i, flags, seen_dashdash, show_merge;
740         const char **unrecognized = argv + 1;
741         int left = 1;
742         int all_match = 0;
743
744         /* First, search for "--" */
745         seen_dashdash = 0;
746         for (i = 1; i < argc; i++) {
747                 const char *arg = argv[i];
748                 if (strcmp(arg, "--"))
749                         continue;
750                 argv[i] = NULL;
751                 argc = i;
752                 revs->prune_data = get_pathspec(revs->prefix, argv + i + 1);
753                 seen_dashdash = 1;
754                 break;
755         }
756
757         flags = show_merge = 0;
758         for (i = 1; i < argc; i++) {
759                 const char *arg = argv[i];
760                 if (*arg == '-') {
761                         int opts;
762                         if (!strncmp(arg, "--max-count=", 12)) {
763                                 revs->max_count = atoi(arg + 12);
764                                 continue;
765                         }
766                         if (!strncmp(arg, "--skip=", 7)) {
767                                 revs->skip_count = atoi(arg + 7);
768                                 continue;
769                         }
770                         /* accept -<digit>, like traditional "head" */
771                         if ((*arg == '-') && isdigit(arg[1])) {
772                                 revs->max_count = atoi(arg + 1);
773                                 continue;
774                         }
775                         if (!strcmp(arg, "-n")) {
776                                 if (argc <= i + 1)
777                                         die("-n requires an argument");
778                                 revs->max_count = atoi(argv[++i]);
779                                 continue;
780                         }
781                         if (!strncmp(arg,"-n",2)) {
782                                 revs->max_count = atoi(arg + 2);
783                                 continue;
784                         }
785                         if (!strncmp(arg, "--max-age=", 10)) {
786                                 revs->max_age = atoi(arg + 10);
787                                 continue;
788                         }
789                         if (!strncmp(arg, "--since=", 8)) {
790                                 revs->max_age = approxidate(arg + 8);
791                                 continue;
792                         }
793                         if (!strncmp(arg, "--after=", 8)) {
794                                 revs->max_age = approxidate(arg + 8);
795                                 continue;
796                         }
797                         if (!strncmp(arg, "--min-age=", 10)) {
798                                 revs->min_age = atoi(arg + 10);
799                                 continue;
800                         }
801                         if (!strncmp(arg, "--before=", 9)) {
802                                 revs->min_age = approxidate(arg + 9);
803                                 continue;
804                         }
805                         if (!strncmp(arg, "--until=", 8)) {
806                                 revs->min_age = approxidate(arg + 8);
807                                 continue;
808                         }
809                         if (!strcmp(arg, "--all")) {
810                                 handle_all(revs, flags);
811                                 continue;
812                         }
813                         if (!strcmp(arg, "--not")) {
814                                 flags ^= UNINTERESTING;
815                                 continue;
816                         }
817                         if (!strcmp(arg, "--default")) {
818                                 if (++i >= argc)
819                                         die("bad --default argument");
820                                 def = argv[i];
821                                 continue;
822                         }
823                         if (!strcmp(arg, "--merge")) {
824                                 show_merge = 1;
825                                 continue;
826                         }
827                         if (!strcmp(arg, "--topo-order")) {
828                                 revs->topo_order = 1;
829                                 continue;
830                         }
831                         if (!strcmp(arg, "--date-order")) {
832                                 revs->lifo = 0;
833                                 revs->topo_order = 1;
834                                 continue;
835                         }
836                         if (!strcmp(arg, "--parents")) {
837                                 revs->parents = 1;
838                                 continue;
839                         }
840                         if (!strcmp(arg, "--dense")) {
841                                 revs->dense = 1;
842                                 continue;
843                         }
844                         if (!strcmp(arg, "--sparse")) {
845                                 revs->dense = 0;
846                                 continue;
847                         }
848                         if (!strcmp(arg, "--remove-empty")) {
849                                 revs->remove_empty_trees = 1;
850                                 continue;
851                         }
852                         if (!strcmp(arg, "--no-merges")) {
853                                 revs->no_merges = 1;
854                                 continue;
855                         }
856                         if (!strcmp(arg, "--boundary")) {
857                                 revs->boundary = 1;
858                                 continue;
859                         }
860                         if (!strcmp(arg, "--left-right")) {
861                                 revs->left_right = 1;
862                                 continue;
863                         }
864                         if (!strcmp(arg, "--objects")) {
865                                 revs->tag_objects = 1;
866                                 revs->tree_objects = 1;
867                                 revs->blob_objects = 1;
868                                 continue;
869                         }
870                         if (!strcmp(arg, "--objects-edge")) {
871                                 revs->tag_objects = 1;
872                                 revs->tree_objects = 1;
873                                 revs->blob_objects = 1;
874                                 revs->edge_hint = 1;
875                                 continue;
876                         }
877                         if (!strcmp(arg, "--unpacked")) {
878                                 revs->unpacked = 1;
879                                 free(revs->ignore_packed);
880                                 revs->ignore_packed = NULL;
881                                 revs->num_ignore_packed = 0;
882                                 continue;
883                         }
884                         if (!strncmp(arg, "--unpacked=", 11)) {
885                                 revs->unpacked = 1;
886                                 add_ignore_packed(revs, arg+11);
887                                 continue;
888                         }
889                         if (!strcmp(arg, "-r")) {
890                                 revs->diff = 1;
891                                 revs->diffopt.recursive = 1;
892                                 continue;
893                         }
894                         if (!strcmp(arg, "-t")) {
895                                 revs->diff = 1;
896                                 revs->diffopt.recursive = 1;
897                                 revs->diffopt.tree_in_recursive = 1;
898                                 continue;
899                         }
900                         if (!strcmp(arg, "-m")) {
901                                 revs->ignore_merges = 0;
902                                 continue;
903                         }
904                         if (!strcmp(arg, "-c")) {
905                                 revs->diff = 1;
906                                 revs->dense_combined_merges = 0;
907                                 revs->combine_merges = 1;
908                                 continue;
909                         }
910                         if (!strcmp(arg, "--cc")) {
911                                 revs->diff = 1;
912                                 revs->dense_combined_merges = 1;
913                                 revs->combine_merges = 1;
914                                 continue;
915                         }
916                         if (!strcmp(arg, "-v")) {
917                                 revs->verbose_header = 1;
918                                 continue;
919                         }
920                         if (!strncmp(arg, "--pretty", 8)) {
921                                 revs->verbose_header = 1;
922                                 revs->commit_format = get_commit_format(arg+8);
923                                 continue;
924                         }
925                         if (!strcmp(arg, "--root")) {
926                                 revs->show_root_diff = 1;
927                                 continue;
928                         }
929                         if (!strcmp(arg, "--no-commit-id")) {
930                                 revs->no_commit_id = 1;
931                                 continue;
932                         }
933                         if (!strcmp(arg, "--always")) {
934                                 revs->always_show_header = 1;
935                                 continue;
936                         }
937                         if (!strcmp(arg, "--no-abbrev")) {
938                                 revs->abbrev = 0;
939                                 continue;
940                         }
941                         if (!strcmp(arg, "--abbrev")) {
942                                 revs->abbrev = DEFAULT_ABBREV;
943                                 continue;
944                         }
945                         if (!strncmp(arg, "--abbrev=", 9)) {
946                                 revs->abbrev = strtoul(arg + 9, NULL, 10);
947                                 if (revs->abbrev < MINIMUM_ABBREV)
948                                         revs->abbrev = MINIMUM_ABBREV;
949                                 else if (revs->abbrev > 40)
950                                         revs->abbrev = 40;
951                                 continue;
952                         }
953                         if (!strcmp(arg, "--abbrev-commit")) {
954                                 revs->abbrev_commit = 1;
955                                 continue;
956                         }
957                         if (!strcmp(arg, "--full-diff")) {
958                                 revs->diff = 1;
959                                 revs->full_diff = 1;
960                                 continue;
961                         }
962                         if (!strcmp(arg, "--full-history")) {
963                                 revs->simplify_history = 0;
964                                 continue;
965                         }
966                         if (!strcmp(arg, "--relative-date")) {
967                                 revs->relative_date = 1;
968                                 continue;
969                         }
970
971                         /*
972                          * Grepping the commit log
973                          */
974                         if (!strncmp(arg, "--author=", 9)) {
975                                 add_header_grep(revs, "author", arg+9);
976                                 continue;
977                         }
978                         if (!strncmp(arg, "--committer=", 12)) {
979                                 add_header_grep(revs, "committer", arg+12);
980                                 continue;
981                         }
982                         if (!strncmp(arg, "--grep=", 7)) {
983                                 add_message_grep(revs, arg+7);
984                                 continue;
985                         }
986                         if (!strcmp(arg, "--all-match")) {
987                                 all_match = 1;
988                                 continue;
989                         }
990
991                         opts = diff_opt_parse(&revs->diffopt, argv+i, argc-i);
992                         if (opts > 0) {
993                                 revs->diff = 1;
994                                 i += opts - 1;
995                                 continue;
996                         }
997                         *unrecognized++ = arg;
998                         left++;
999                         continue;
1000                 }
1001
1002                 if (handle_revision_arg(arg, revs, flags, seen_dashdash)) {
1003                         int j;
1004                         if (seen_dashdash || *arg == '^')
1005                                 die("bad revision '%s'", arg);
1006
1007                         /* If we didn't have a "--":
1008                          * (1) all filenames must exist;
1009                          * (2) all rev-args must not be interpretable
1010                          *     as a valid filename.
1011                          * but the latter we have checked in the main loop.
1012                          */
1013                         for (j = i; j < argc; j++)
1014                                 verify_filename(revs->prefix, argv[j]);
1015
1016                         revs->prune_data = get_pathspec(revs->prefix,
1017                                                         argv + i);
1018                         break;
1019                 }
1020         }
1021
1022         if (show_merge)
1023                 prepare_show_merge(revs);
1024         if (def && !revs->pending.nr) {
1025                 unsigned char sha1[20];
1026                 struct object *object;
1027                 if (get_sha1(def, sha1))
1028                         die("bad default revision '%s'", def);
1029                 object = get_reference(revs, def, sha1, 0);
1030                 add_pending_object(revs, object, def);
1031         }
1032
1033         if (revs->topo_order)
1034                 revs->limited = 1;
1035
1036         if (revs->prune_data) {
1037                 diff_tree_setup_paths(revs->prune_data, &revs->pruning);
1038                 revs->prune_fn = try_to_simplify_commit;
1039                 if (!revs->full_diff)
1040                         diff_tree_setup_paths(revs->prune_data, &revs->diffopt);
1041         }
1042         if (revs->combine_merges) {
1043                 revs->ignore_merges = 0;
1044                 if (revs->dense_combined_merges && !revs->diffopt.output_format)
1045                         revs->diffopt.output_format = DIFF_FORMAT_PATCH;
1046         }
1047         revs->diffopt.abbrev = revs->abbrev;
1048         if (diff_setup_done(&revs->diffopt) < 0)
1049                 die("diff_setup_done failed");
1050
1051         if (revs->grep_filter) {
1052                 revs->grep_filter->all_match = all_match;
1053                 compile_grep_patterns(revs->grep_filter);
1054         }
1055
1056         return left;
1057 }
1058
1059 void prepare_revision_walk(struct rev_info *revs)
1060 {
1061         int nr = revs->pending.nr;
1062         struct object_array_entry *list = revs->pending.objects;
1063
1064         revs->pending.nr = 0;
1065         revs->pending.alloc = 0;
1066         revs->pending.objects = NULL;
1067         while (--nr >= 0) {
1068                 struct commit *commit = handle_commit(revs, list->item, list->name);
1069                 if (commit) {
1070                         if (!(commit->object.flags & SEEN)) {
1071                                 commit->object.flags |= SEEN;
1072                                 insert_by_date(commit, &revs->commits);
1073                         }
1074                 }
1075                 list++;
1076         }
1077
1078         if (revs->no_walk)
1079                 return;
1080         if (revs->limited)
1081                 limit_list(revs);
1082         if (revs->topo_order)
1083                 sort_in_topological_order_fn(&revs->commits, revs->lifo,
1084                                              revs->topo_setter,
1085                                              revs->topo_getter);
1086 }
1087
1088 static int rewrite_one(struct rev_info *revs, struct commit **pp)
1089 {
1090         for (;;) {
1091                 struct commit *p = *pp;
1092                 if (!revs->limited)
1093                         add_parents_to_list(revs, p, &revs->commits);
1094                 if (p->parents && p->parents->next)
1095                         return 0;
1096                 if (p->object.flags & (TREECHANGE | UNINTERESTING))
1097                         return 0;
1098                 if (!p->parents)
1099                         return -1;
1100                 *pp = p->parents->item;
1101         }
1102 }
1103
1104 static void rewrite_parents(struct rev_info *revs, struct commit *commit)
1105 {
1106         struct commit_list **pp = &commit->parents;
1107         while (*pp) {
1108                 struct commit_list *parent = *pp;
1109                 if (rewrite_one(revs, &parent->item) < 0) {
1110                         *pp = parent->next;
1111                         continue;
1112                 }
1113                 pp = &parent->next;
1114         }
1115 }
1116
1117 static void mark_boundary_to_show(struct commit *commit)
1118 {
1119         struct commit_list *p = commit->parents;
1120         while (p) {
1121                 commit = p->item;
1122                 p = p->next;
1123                 if (commit->object.flags & BOUNDARY)
1124                         commit->object.flags |= BOUNDARY_SHOW;
1125         }
1126 }
1127
1128 static int commit_match(struct commit *commit, struct rev_info *opt)
1129 {
1130         if (!opt->grep_filter)
1131                 return 1;
1132         return grep_buffer(opt->grep_filter,
1133                            NULL, /* we say nothing, not even filename */
1134                            commit->buffer, strlen(commit->buffer));
1135 }
1136
1137 static struct commit *get_revision_1(struct rev_info *revs)
1138 {
1139         if (!revs->commits)
1140                 return NULL;
1141
1142         do {
1143                 struct commit_list *entry = revs->commits;
1144                 struct commit *commit = entry->item;
1145
1146                 revs->commits = entry->next;
1147                 free(entry);
1148
1149                 /*
1150                  * If we haven't done the list limiting, we need to look at
1151                  * the parents here. We also need to do the date-based limiting
1152                  * that we'd otherwise have done in limit_list().
1153                  */
1154                 if (!revs->limited) {
1155                         if (revs->max_age != -1 &&
1156                             (commit->date < revs->max_age))
1157                                 continue;
1158                         add_parents_to_list(revs, commit, &revs->commits);
1159                 }
1160                 if (commit->object.flags & SHOWN)
1161                         continue;
1162
1163                 if (revs->unpacked && has_sha1_pack(commit->object.sha1,
1164                                                     revs->ignore_packed))
1165                     continue;
1166
1167                 /* We want to show boundary commits only when their
1168                  * children are shown.  When path-limiter is in effect,
1169                  * rewrite_parents() drops some commits from getting shown,
1170                  * and there is no point showing boundary parents that
1171                  * are not shown.  After rewrite_parents() rewrites the
1172                  * parents of a commit that is shown, we mark the boundary
1173                  * parents with BOUNDARY_SHOW.
1174                  */
1175                 if (commit->object.flags & BOUNDARY_SHOW) {
1176                         commit->object.flags |= SHOWN;
1177                         return commit;
1178                 }
1179                 if (commit->object.flags & UNINTERESTING)
1180                         continue;
1181                 if (revs->min_age != -1 && (commit->date > revs->min_age))
1182                         continue;
1183                 if (revs->no_merges &&
1184                     commit->parents && commit->parents->next)
1185                         continue;
1186                 if (!commit_match(commit, revs))
1187                         continue;
1188                 if (revs->prune_fn && revs->dense) {
1189                         /* Commit without changes? */
1190                         if (!(commit->object.flags & TREECHANGE)) {
1191                                 /* drop merges unless we want parenthood */
1192                                 if (!revs->parents)
1193                                         continue;
1194                                 /* non-merge - always ignore it */
1195                                 if (!commit->parents || !commit->parents->next)
1196                                         continue;
1197                         }
1198                         if (revs->parents)
1199                                 rewrite_parents(revs, commit);
1200                 }
1201                 if (revs->boundary)
1202                         mark_boundary_to_show(commit);
1203                 commit->object.flags |= SHOWN;
1204                 return commit;
1205         } while (revs->commits);
1206         return NULL;
1207 }
1208
1209 struct commit *get_revision(struct rev_info *revs)
1210 {
1211         struct commit *c = NULL;
1212
1213         if (0 < revs->skip_count) {
1214                 while ((c = get_revision_1(revs)) != NULL) {
1215                         if (revs->skip_count-- <= 0)
1216                                 break;
1217                 }
1218         }
1219
1220         /* Check the max_count ... */
1221         switch (revs->max_count) {
1222         case -1:
1223                 break;
1224         case 0:
1225                 return NULL;
1226         default:
1227                 revs->max_count--;
1228         }
1229         if (c)
1230                 return c;
1231         return get_revision_1(revs);
1232 }