2e80930b2cec2e20be00b5d7751af6a6626efdc2
[git/git.git] / rev-list.c
1 #include "cache.h"
2 #include "refs.h"
3 #include "tag.h"
4 #include "commit.h"
5 #include "tree.h"
6 #include "blob.h"
7 #include "epoch.h"
8 #include "diff.h"
9 #include "revision.h"
10
11 /* bits #0 and #1 in revision.h */
12
13 #define COUNTED (1u << 2)
14 #define SHOWN (1u << 3)
15 #define TREECHANGE (1u << 4)
16 #define TMP_MARK (1u << 5) /* for isolated cases; clean after use */
17
18 static const char rev_list_usage[] =
19 "git-rev-list [OPTION] <commit-id>... [ -- paths... ]\n"
20 " limiting output:\n"
21 " --max-count=nr\n"
22 " --max-age=epoch\n"
23 " --min-age=epoch\n"
24 " --sparse\n"
25 " --no-merges\n"
26 " --remove-empty\n"
27 " --all\n"
28 " ordering output:\n"
29 " --merge-order [ --show-breaks ]\n"
30 " --topo-order\n"
31 " --date-order\n"
32 " formatting output:\n"
33 " --parents\n"
34 " --objects | --objects-edge\n"
35 " --unpacked\n"
36 " --header | --pretty\n"
37 " --abbrev=nr | --no-abbrev\n"
38 " special purpose:\n"
39 " --bisect"
40 ;
41
42 struct rev_info revs;
43
44 static int bisect_list = 0;
45 static int verbose_header = 0;
46 static int abbrev = DEFAULT_ABBREV;
47 static int show_parents = 0;
48 static int hdr_termination = 0;
49 static const char *commit_prefix = "";
50 static enum cmit_fmt commit_format = CMIT_FMT_RAW;
51 static int merge_order = 0;
52 static int show_breaks = 0;
53 static int stop_traversal = 0;
54 static int no_merges = 0;
55
56 static void show_commit(struct commit *commit)
57 {
58 commit->object.flags |= SHOWN;
59 if (show_breaks) {
60 commit_prefix = "| ";
61 if (commit->object.flags & DISCONTINUITY) {
62 commit_prefix = "^ ";
63 } else if (commit->object.flags & BOUNDARY) {
64 commit_prefix = "= ";
65 }
66 }
67 printf("%s%s", commit_prefix, sha1_to_hex(commit->object.sha1));
68 if (show_parents) {
69 struct commit_list *parents = commit->parents;
70 while (parents) {
71 struct object *o = &(parents->item->object);
72 parents = parents->next;
73 if (o->flags & TMP_MARK)
74 continue;
75 printf(" %s", sha1_to_hex(o->sha1));
76 o->flags |= TMP_MARK;
77 }
78 /* TMP_MARK is a general purpose flag that can
79 * be used locally, but the user should clean
80 * things up after it is done with them.
81 */
82 for (parents = commit->parents;
83 parents;
84 parents = parents->next)
85 parents->item->object.flags &= ~TMP_MARK;
86 }
87 if (commit_format == CMIT_FMT_ONELINE)
88 putchar(' ');
89 else
90 putchar('\n');
91
92 if (verbose_header) {
93 static char pretty_header[16384];
94 pretty_print_commit(commit_format, commit, ~0, pretty_header, sizeof(pretty_header), abbrev);
95 printf("%s%c", pretty_header, hdr_termination);
96 }
97 fflush(stdout);
98 }
99
100 static int rewrite_one(struct commit **pp)
101 {
102 for (;;) {
103 struct commit *p = *pp;
104 if (p->object.flags & (TREECHANGE | UNINTERESTING))
105 return 0;
106 if (!p->parents)
107 return -1;
108 *pp = p->parents->item;
109 }
110 }
111
112 static void rewrite_parents(struct commit *commit)
113 {
114 struct commit_list **pp = &commit->parents;
115 while (*pp) {
116 struct commit_list *parent = *pp;
117 if (rewrite_one(&parent->item) < 0) {
118 *pp = parent->next;
119 continue;
120 }
121 pp = &parent->next;
122 }
123 }
124
125 static int filter_commit(struct commit * commit)
126 {
127 if (stop_traversal && (commit->object.flags & BOUNDARY))
128 return STOP;
129 if (commit->object.flags & (UNINTERESTING|SHOWN))
130 return CONTINUE;
131 if (revs.min_age != -1 && (commit->date > revs.min_age))
132 return CONTINUE;
133 if (revs.max_age != -1 && (commit->date < revs.max_age)) {
134 stop_traversal=1;
135 return CONTINUE;
136 }
137 if (no_merges && (commit->parents && commit->parents->next))
138 return CONTINUE;
139 if (revs.paths && revs.dense) {
140 if (!(commit->object.flags & TREECHANGE))
141 return CONTINUE;
142 rewrite_parents(commit);
143 }
144 return DO;
145 }
146
147 static int process_commit(struct commit * commit)
148 {
149 int action=filter_commit(commit);
150
151 if (action == STOP) {
152 return STOP;
153 }
154
155 if (action == CONTINUE) {
156 return CONTINUE;
157 }
158
159 if (revs.max_count != -1 && !revs.max_count--)
160 return STOP;
161
162 show_commit(commit);
163
164 return CONTINUE;
165 }
166
167 static struct object_list **process_blob(struct blob *blob,
168 struct object_list **p,
169 struct name_path *path,
170 const char *name)
171 {
172 struct object *obj = &blob->object;
173
174 if (!revs.blob_objects)
175 return p;
176 if (obj->flags & (UNINTERESTING | SEEN))
177 return p;
178 obj->flags |= SEEN;
179 return add_object(obj, p, path, name);
180 }
181
182 static struct object_list **process_tree(struct tree *tree,
183 struct object_list **p,
184 struct name_path *path,
185 const char *name)
186 {
187 struct object *obj = &tree->object;
188 struct tree_entry_list *entry;
189 struct name_path me;
190
191 if (!revs.tree_objects)
192 return p;
193 if (obj->flags & (UNINTERESTING | SEEN))
194 return p;
195 if (parse_tree(tree) < 0)
196 die("bad tree object %s", sha1_to_hex(obj->sha1));
197 obj->flags |= SEEN;
198 p = add_object(obj, p, path, name);
199 me.up = path;
200 me.elem = name;
201 me.elem_len = strlen(name);
202 entry = tree->entries;
203 tree->entries = NULL;
204 while (entry) {
205 struct tree_entry_list *next = entry->next;
206 if (entry->directory)
207 p = process_tree(entry->item.tree, p, &me, entry->name);
208 else
209 p = process_blob(entry->item.blob, p, &me, entry->name);
210 free(entry);
211 entry = next;
212 }
213 return p;
214 }
215
216 static void show_commit_list(struct commit_list *list)
217 {
218 struct object_list *objects = NULL, **p = &objects, *pending;
219 while (list) {
220 struct commit *commit = pop_most_recent_commit(&list, SEEN);
221
222 p = process_tree(commit->tree, p, NULL, "");
223 if (process_commit(commit) == STOP)
224 break;
225 }
226 for (pending = revs.pending_objects; pending; pending = pending->next) {
227 struct object *obj = pending->item;
228 const char *name = pending->name;
229 if (obj->flags & (UNINTERESTING | SEEN))
230 continue;
231 if (obj->type == tag_type) {
232 obj->flags |= SEEN;
233 p = add_object(obj, p, NULL, name);
234 continue;
235 }
236 if (obj->type == tree_type) {
237 p = process_tree((struct tree *)obj, p, NULL, name);
238 continue;
239 }
240 if (obj->type == blob_type) {
241 p = process_blob((struct blob *)obj, p, NULL, name);
242 continue;
243 }
244 die("unknown pending object %s (%s)", sha1_to_hex(obj->sha1), name);
245 }
246 while (objects) {
247 /* An object with name "foo\n0000000..." can be used to
248 * confuse downstream git-pack-objects very badly.
249 */
250 const char *ep = strchr(objects->name, '\n');
251 if (ep) {
252 printf("%s %.*s\n", sha1_to_hex(objects->item->sha1),
253 (int) (ep - objects->name),
254 objects->name);
255 }
256 else
257 printf("%s %s\n", sha1_to_hex(objects->item->sha1), objects->name);
258 objects = objects->next;
259 }
260 }
261
262 static int everybody_uninteresting(struct commit_list *orig)
263 {
264 struct commit_list *list = orig;
265 while (list) {
266 struct commit *commit = list->item;
267 list = list->next;
268 if (commit->object.flags & UNINTERESTING)
269 continue;
270 return 0;
271 }
272 return 1;
273 }
274
275 /*
276 * This is a truly stupid algorithm, but it's only
277 * used for bisection, and we just don't care enough.
278 *
279 * We care just barely enough to avoid recursing for
280 * non-merge entries.
281 */
282 static int count_distance(struct commit_list *entry)
283 {
284 int nr = 0;
285
286 while (entry) {
287 struct commit *commit = entry->item;
288 struct commit_list *p;
289
290 if (commit->object.flags & (UNINTERESTING | COUNTED))
291 break;
292 if (!revs.paths || (commit->object.flags & TREECHANGE))
293 nr++;
294 commit->object.flags |= COUNTED;
295 p = commit->parents;
296 entry = p;
297 if (p) {
298 p = p->next;
299 while (p) {
300 nr += count_distance(p);
301 p = p->next;
302 }
303 }
304 }
305
306 return nr;
307 }
308
309 static void clear_distance(struct commit_list *list)
310 {
311 while (list) {
312 struct commit *commit = list->item;
313 commit->object.flags &= ~COUNTED;
314 list = list->next;
315 }
316 }
317
318 static struct commit_list *find_bisection(struct commit_list *list)
319 {
320 int nr, closest;
321 struct commit_list *p, *best;
322
323 nr = 0;
324 p = list;
325 while (p) {
326 if (!revs.paths || (p->item->object.flags & TREECHANGE))
327 nr++;
328 p = p->next;
329 }
330 closest = 0;
331 best = list;
332
333 for (p = list; p; p = p->next) {
334 int distance;
335
336 if (revs.paths && !(p->item->object.flags & TREECHANGE))
337 continue;
338
339 distance = count_distance(p);
340 clear_distance(list);
341 if (nr - distance < distance)
342 distance = nr - distance;
343 if (distance > closest) {
344 best = p;
345 closest = distance;
346 }
347 }
348 if (best)
349 best->next = NULL;
350 return best;
351 }
352
353 static void mark_edge_parents_uninteresting(struct commit *commit)
354 {
355 struct commit_list *parents;
356
357 for (parents = commit->parents; parents; parents = parents->next) {
358 struct commit *parent = parents->item;
359 if (!(parent->object.flags & UNINTERESTING))
360 continue;
361 mark_tree_uninteresting(parent->tree);
362 if (revs.edge_hint && !(parent->object.flags & SHOWN)) {
363 parent->object.flags |= SHOWN;
364 printf("-%s\n", sha1_to_hex(parent->object.sha1));
365 }
366 }
367 }
368
369 static void mark_edges_uninteresting(struct commit_list *list)
370 {
371 for ( ; list; list = list->next) {
372 struct commit *commit = list->item;
373
374 if (commit->object.flags & UNINTERESTING) {
375 mark_tree_uninteresting(commit->tree);
376 continue;
377 }
378 mark_edge_parents_uninteresting(commit);
379 }
380 }
381
382 #define TREE_SAME 0
383 #define TREE_NEW 1
384 #define TREE_DIFFERENT 2
385 static int tree_difference = TREE_SAME;
386
387 static void file_add_remove(struct diff_options *options,
388 int addremove, unsigned mode,
389 const unsigned char *sha1,
390 const char *base, const char *path)
391 {
392 int diff = TREE_DIFFERENT;
393
394 /*
395 * Is it an add of a new file? It means that
396 * the old tree didn't have it at all, so we
397 * will turn "TREE_SAME" -> "TREE_NEW", but
398 * leave any "TREE_DIFFERENT" alone (and if
399 * it already was "TREE_NEW", we'll keep it
400 * "TREE_NEW" of course).
401 */
402 if (addremove == '+') {
403 diff = tree_difference;
404 if (diff != TREE_SAME)
405 return;
406 diff = TREE_NEW;
407 }
408 tree_difference = diff;
409 }
410
411 static void file_change(struct diff_options *options,
412 unsigned old_mode, unsigned new_mode,
413 const unsigned char *old_sha1,
414 const unsigned char *new_sha1,
415 const char *base, const char *path)
416 {
417 tree_difference = TREE_DIFFERENT;
418 }
419
420 static struct diff_options diff_opt = {
421 .recursive = 1,
422 .add_remove = file_add_remove,
423 .change = file_change,
424 };
425
426 static int compare_tree(struct tree *t1, struct tree *t2)
427 {
428 if (!t1)
429 return TREE_NEW;
430 if (!t2)
431 return TREE_DIFFERENT;
432 tree_difference = TREE_SAME;
433 if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "", &diff_opt) < 0)
434 return TREE_DIFFERENT;
435 return tree_difference;
436 }
437
438 static int same_tree_as_empty(struct tree *t1)
439 {
440 int retval;
441 void *tree;
442 struct tree_desc empty, real;
443
444 if (!t1)
445 return 0;
446
447 tree = read_object_with_reference(t1->object.sha1, "tree", &real.size, NULL);
448 if (!tree)
449 return 0;
450 real.buf = tree;
451
452 empty.buf = "";
453 empty.size = 0;
454
455 tree_difference = 0;
456 retval = diff_tree(&empty, &real, "", &diff_opt);
457 free(tree);
458
459 return retval >= 0 && !tree_difference;
460 }
461
462 static void try_to_simplify_commit(struct commit *commit)
463 {
464 struct commit_list **pp, *parent;
465
466 if (!commit->tree)
467 return;
468
469 if (!commit->parents) {
470 if (!same_tree_as_empty(commit->tree))
471 commit->object.flags |= TREECHANGE;
472 return;
473 }
474
475 pp = &commit->parents;
476 while ((parent = *pp) != NULL) {
477 struct commit *p = parent->item;
478
479 if (p->object.flags & UNINTERESTING) {
480 pp = &parent->next;
481 continue;
482 }
483
484 parse_commit(p);
485 switch (compare_tree(p->tree, commit->tree)) {
486 case TREE_SAME:
487 parent->next = NULL;
488 commit->parents = parent;
489 return;
490
491 case TREE_NEW:
492 if (revs.remove_empty_trees && same_tree_as_empty(p->tree)) {
493 *pp = parent->next;
494 continue;
495 }
496 /* fallthrough */
497 case TREE_DIFFERENT:
498 pp = &parent->next;
499 continue;
500 }
501 die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
502 }
503 commit->object.flags |= TREECHANGE;
504 }
505
506 static void add_parents_to_list(struct commit *commit, struct commit_list **list)
507 {
508 struct commit_list *parent = commit->parents;
509
510 /*
511 * If the commit is uninteresting, don't try to
512 * prune parents - we want the maximal uninteresting
513 * set.
514 *
515 * Normally we haven't parsed the parent
516 * yet, so we won't have a parent of a parent
517 * here. However, it may turn out that we've
518 * reached this commit some other way (where it
519 * wasn't uninteresting), in which case we need
520 * to mark its parents recursively too..
521 */
522 if (commit->object.flags & UNINTERESTING) {
523 while (parent) {
524 struct commit *p = parent->item;
525 parent = parent->next;
526 parse_commit(p);
527 p->object.flags |= UNINTERESTING;
528 if (p->parents)
529 mark_parents_uninteresting(p);
530 if (p->object.flags & SEEN)
531 continue;
532 p->object.flags |= SEEN;
533 insert_by_date(p, list);
534 }
535 return;
536 }
537
538 /*
539 * Ok, the commit wasn't uninteresting. Try to
540 * simplify the commit history and find the parent
541 * that has no differences in the path set if one exists.
542 */
543 if (revs.paths)
544 try_to_simplify_commit(commit);
545
546 parent = commit->parents;
547 while (parent) {
548 struct commit *p = parent->item;
549
550 parent = parent->next;
551
552 parse_commit(p);
553 if (p->object.flags & SEEN)
554 continue;
555 p->object.flags |= SEEN;
556 insert_by_date(p, list);
557 }
558 }
559
560 static struct commit_list *limit_list(struct commit_list *list)
561 {
562 struct commit_list *newlist = NULL;
563 struct commit_list **p = &newlist;
564 while (list) {
565 struct commit_list *entry = list;
566 struct commit *commit = list->item;
567 struct object *obj = &commit->object;
568
569 list = list->next;
570 free(entry);
571
572 if (revs.max_age != -1 && (commit->date < revs.max_age))
573 obj->flags |= UNINTERESTING;
574 if (revs.unpacked && has_sha1_pack(obj->sha1))
575 obj->flags |= UNINTERESTING;
576 add_parents_to_list(commit, &list);
577 if (obj->flags & UNINTERESTING) {
578 mark_parents_uninteresting(commit);
579 if (everybody_uninteresting(list))
580 break;
581 continue;
582 }
583 if (revs.min_age != -1 && (commit->date > revs.min_age))
584 continue;
585 p = &commit_list_insert(commit, p)->next;
586 }
587 if (revs.tree_objects)
588 mark_edges_uninteresting(newlist);
589 if (bisect_list)
590 newlist = find_bisection(newlist);
591 return newlist;
592 }
593
594 int main(int argc, const char **argv)
595 {
596 struct commit_list *list;
597 int i;
598
599 argc = setup_revisions(argc, argv, &revs);
600
601 for (i = 1 ; i < argc; i++) {
602 const char *arg = argv[i];
603
604 /* accept -<digit>, like traditilnal "head" */
605 if ((*arg == '-') && isdigit(arg[1])) {
606 revs.max_count = atoi(arg + 1);
607 continue;
608 }
609 if (!strcmp(arg, "-n")) {
610 if (++i >= argc)
611 die("-n requires an argument");
612 revs.max_count = atoi(argv[i]);
613 continue;
614 }
615 if (!strncmp(arg,"-n",2)) {
616 revs.max_count = atoi(arg + 2);
617 continue;
618 }
619 if (!strcmp(arg, "--header")) {
620 verbose_header = 1;
621 continue;
622 }
623 if (!strcmp(arg, "--no-abbrev")) {
624 abbrev = 0;
625 continue;
626 }
627 if (!strncmp(arg, "--abbrev=", 9)) {
628 abbrev = strtoul(arg + 9, NULL, 10);
629 if (abbrev && abbrev < MINIMUM_ABBREV)
630 abbrev = MINIMUM_ABBREV;
631 else if (40 < abbrev)
632 abbrev = 40;
633 continue;
634 }
635 if (!strncmp(arg, "--pretty", 8)) {
636 commit_format = get_commit_format(arg+8);
637 verbose_header = 1;
638 hdr_termination = '\n';
639 if (commit_format == CMIT_FMT_ONELINE)
640 commit_prefix = "";
641 else
642 commit_prefix = "commit ";
643 continue;
644 }
645 if (!strncmp(arg, "--no-merges", 11)) {
646 no_merges = 1;
647 continue;
648 }
649 if (!strcmp(arg, "--parents")) {
650 show_parents = 1;
651 continue;
652 }
653 if (!strcmp(arg, "--bisect")) {
654 bisect_list = 1;
655 continue;
656 }
657 if (!strcmp(arg, "--merge-order")) {
658 merge_order = 1;
659 continue;
660 }
661 if (!strcmp(arg, "--show-breaks")) {
662 show_breaks = 1;
663 continue;
664 }
665 usage(rev_list_usage);
666
667 }
668
669 list = revs.commits;
670
671 if (!list &&
672 (!(revs.tag_objects||revs.tree_objects||revs.blob_objects) && !revs.pending_objects))
673 usage(rev_list_usage);
674
675 if (revs.paths)
676 diff_tree_setup_paths(revs.paths);
677
678 save_commit_buffer = verbose_header;
679 track_object_refs = 0;
680
681 if (!merge_order) {
682 sort_by_date(&list);
683 if (list && !revs.limited && revs.max_count == 1 &&
684 !revs.tag_objects && !revs.tree_objects && !revs.blob_objects) {
685 show_commit(list->item);
686 return 0;
687 }
688 if (revs.limited)
689 list = limit_list(list);
690 if (revs.topo_order)
691 sort_in_topological_order(&list, revs.lifo);
692 show_commit_list(list);
693 } else {
694 #ifndef NO_OPENSSL
695 if (sort_list_in_merge_order(list, &process_commit)) {
696 die("merge order sort failed\n");
697 }
698 #else
699 die("merge order sort unsupported, OpenSSL not linked");
700 #endif
701 }
702
703 return 0;
704 }