process_{tree,blob}: show objects without buffering
[git/git.git] / builtin-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 "tree-walk.h"
8 #include "diff.h"
9 #include "revision.h"
10 #include "list-objects.h"
11 #include "builtin.h"
12 #include "log-tree.h"
13 #include "graph.h"
14
15 /* bits #0-15 in revision.h */
16
17 #define COUNTED (1u<<16)
18
19 static const char rev_list_usage[] =
20 "git rev-list [OPTION] <commit-id>... [ -- paths... ]\n"
21 " limiting output:\n"
22 " --max-count=nr\n"
23 " --max-age=epoch\n"
24 " --min-age=epoch\n"
25 " --sparse\n"
26 " --no-merges\n"
27 " --remove-empty\n"
28 " --all\n"
29 " --branches\n"
30 " --tags\n"
31 " --remotes\n"
32 " --stdin\n"
33 " --quiet\n"
34 " ordering output:\n"
35 " --topo-order\n"
36 " --date-order\n"
37 " --reverse\n"
38 " formatting output:\n"
39 " --parents\n"
40 " --children\n"
41 " --objects | --objects-edge\n"
42 " --unpacked\n"
43 " --header | --pretty\n"
44 " --abbrev=nr | --no-abbrev\n"
45 " --abbrev-commit\n"
46 " --left-right\n"
47 " special purpose:\n"
48 " --bisect\n"
49 " --bisect-vars\n"
50 " --bisect-all"
51 ;
52
53 static struct rev_info revs;
54
55 static int bisect_list;
56 static int show_timestamp;
57 static int hdr_termination;
58 static const char *header_prefix;
59
60 static void finish_commit(struct commit *commit);
61 static void show_commit(struct commit *commit)
62 {
63 graph_show_commit(revs.graph);
64
65 if (show_timestamp)
66 printf("%lu ", commit->date);
67 if (header_prefix)
68 fputs(header_prefix, stdout);
69
70 if (!revs.graph) {
71 if (commit->object.flags & BOUNDARY)
72 putchar('-');
73 else if (commit->object.flags & UNINTERESTING)
74 putchar('^');
75 else if (revs.left_right) {
76 if (commit->object.flags & SYMMETRIC_LEFT)
77 putchar('<');
78 else
79 putchar('>');
80 }
81 }
82 if (revs.abbrev_commit && revs.abbrev)
83 fputs(find_unique_abbrev(commit->object.sha1, revs.abbrev),
84 stdout);
85 else
86 fputs(sha1_to_hex(commit->object.sha1), stdout);
87 if (revs.print_parents) {
88 struct commit_list *parents = commit->parents;
89 while (parents) {
90 printf(" %s", sha1_to_hex(parents->item->object.sha1));
91 parents = parents->next;
92 }
93 }
94 if (revs.children.name) {
95 struct commit_list *children;
96
97 children = lookup_decoration(&revs.children, &commit->object);
98 while (children) {
99 printf(" %s", sha1_to_hex(children->item->object.sha1));
100 children = children->next;
101 }
102 }
103 show_decorations(commit);
104 if (revs.commit_format == CMIT_FMT_ONELINE)
105 putchar(' ');
106 else
107 putchar('\n');
108
109 if (revs.verbose_header && commit->buffer) {
110 struct strbuf buf;
111 strbuf_init(&buf, 0);
112 pretty_print_commit(revs.commit_format, commit,
113 &buf, revs.abbrev, NULL, NULL,
114 revs.date_mode, 0);
115 if (revs.graph) {
116 if (buf.len) {
117 if (revs.commit_format != CMIT_FMT_ONELINE)
118 graph_show_oneline(revs.graph);
119
120 graph_show_commit_msg(revs.graph, &buf);
121
122 /*
123 * Add a newline after the commit message.
124 *
125 * Usually, this newline produces a blank
126 * padding line between entries, in which case
127 * we need to add graph padding on this line.
128 *
129 * However, the commit message may not end in a
130 * newline. In this case the newline simply
131 * ends the last line of the commit message,
132 * and we don't need any graph output. (This
133 * always happens with CMIT_FMT_ONELINE, and it
134 * happens with CMIT_FMT_USERFORMAT when the
135 * format doesn't explicitly end in a newline.)
136 */
137 if (buf.len && buf.buf[buf.len - 1] == '\n')
138 graph_show_padding(revs.graph);
139 putchar('\n');
140 } else {
141 /*
142 * If the message buffer is empty, just show
143 * the rest of the graph output for this
144 * commit.
145 */
146 if (graph_show_remainder(revs.graph))
147 putchar('\n');
148 }
149 } else {
150 if (buf.len)
151 printf("%s%c", buf.buf, hdr_termination);
152 }
153 strbuf_release(&buf);
154 } else {
155 if (graph_show_remainder(revs.graph))
156 putchar('\n');
157 }
158 maybe_flush_or_die(stdout, "stdout");
159 finish_commit(commit);
160 }
161
162 static void finish_commit(struct commit *commit)
163 {
164 if (commit->parents) {
165 free_commit_list(commit->parents);
166 commit->parents = NULL;
167 }
168 free(commit->buffer);
169 commit->buffer = NULL;
170 }
171
172 static void finish_object(struct object *obj, const char *name)
173 {
174 if (obj->type == OBJ_BLOB && !has_sha1_file(obj->sha1))
175 die("missing blob object '%s'", sha1_to_hex(obj->sha1));
176 }
177
178 static void show_object(struct object *obj, const char *name)
179 {
180 /* An object with name "foo\n0000000..." can be used to
181 * confuse downstream "git pack-objects" very badly.
182 */
183 const char *ep = strchr(name, '\n');
184
185 finish_object(obj, name);
186 if (ep) {
187 printf("%s %.*s\n", sha1_to_hex(obj->sha1),
188 (int) (ep - name),
189 name);
190 }
191 else
192 printf("%s %s\n", sha1_to_hex(obj->sha1), name);
193 }
194
195 static void show_edge(struct commit *commit)
196 {
197 printf("-%s\n", sha1_to_hex(commit->object.sha1));
198 }
199
200 /*
201 * This is a truly stupid algorithm, but it's only
202 * used for bisection, and we just don't care enough.
203 *
204 * We care just barely enough to avoid recursing for
205 * non-merge entries.
206 */
207 static int count_distance(struct commit_list *entry)
208 {
209 int nr = 0;
210
211 while (entry) {
212 struct commit *commit = entry->item;
213 struct commit_list *p;
214
215 if (commit->object.flags & (UNINTERESTING | COUNTED))
216 break;
217 if (!(commit->object.flags & TREESAME))
218 nr++;
219 commit->object.flags |= COUNTED;
220 p = commit->parents;
221 entry = p;
222 if (p) {
223 p = p->next;
224 while (p) {
225 nr += count_distance(p);
226 p = p->next;
227 }
228 }
229 }
230
231 return nr;
232 }
233
234 static void clear_distance(struct commit_list *list)
235 {
236 while (list) {
237 struct commit *commit = list->item;
238 commit->object.flags &= ~COUNTED;
239 list = list->next;
240 }
241 }
242
243 #define DEBUG_BISECT 0
244
245 static inline int weight(struct commit_list *elem)
246 {
247 return *((int*)(elem->item->util));
248 }
249
250 static inline void weight_set(struct commit_list *elem, int weight)
251 {
252 *((int*)(elem->item->util)) = weight;
253 }
254
255 static int count_interesting_parents(struct commit *commit)
256 {
257 struct commit_list *p;
258 int count;
259
260 for (count = 0, p = commit->parents; p; p = p->next) {
261 if (p->item->object.flags & UNINTERESTING)
262 continue;
263 count++;
264 }
265 return count;
266 }
267
268 static inline int halfway(struct commit_list *p, int nr)
269 {
270 /*
271 * Don't short-cut something we are not going to return!
272 */
273 if (p->item->object.flags & TREESAME)
274 return 0;
275 if (DEBUG_BISECT)
276 return 0;
277 /*
278 * 2 and 3 are halfway of 5.
279 * 3 is halfway of 6 but 2 and 4 are not.
280 */
281 switch (2 * weight(p) - nr) {
282 case -1: case 0: case 1:
283 return 1;
284 default:
285 return 0;
286 }
287 }
288
289 #if !DEBUG_BISECT
290 #define show_list(a,b,c,d) do { ; } while (0)
291 #else
292 static void show_list(const char *debug, int counted, int nr,
293 struct commit_list *list)
294 {
295 struct commit_list *p;
296
297 fprintf(stderr, "%s (%d/%d)\n", debug, counted, nr);
298
299 for (p = list; p; p = p->next) {
300 struct commit_list *pp;
301 struct commit *commit = p->item;
302 unsigned flags = commit->object.flags;
303 enum object_type type;
304 unsigned long size;
305 char *buf = read_sha1_file(commit->object.sha1, &type, &size);
306 char *ep, *sp;
307
308 fprintf(stderr, "%c%c%c ",
309 (flags & TREESAME) ? ' ' : 'T',
310 (flags & UNINTERESTING) ? 'U' : ' ',
311 (flags & COUNTED) ? 'C' : ' ');
312 if (commit->util)
313 fprintf(stderr, "%3d", weight(p));
314 else
315 fprintf(stderr, "---");
316 fprintf(stderr, " %.*s", 8, sha1_to_hex(commit->object.sha1));
317 for (pp = commit->parents; pp; pp = pp->next)
318 fprintf(stderr, " %.*s", 8,
319 sha1_to_hex(pp->item->object.sha1));
320
321 sp = strstr(buf, "\n\n");
322 if (sp) {
323 sp += 2;
324 for (ep = sp; *ep && *ep != '\n'; ep++)
325 ;
326 fprintf(stderr, " %.*s", (int)(ep - sp), sp);
327 }
328 fprintf(stderr, "\n");
329 }
330 }
331 #endif /* DEBUG_BISECT */
332
333 static struct commit_list *best_bisection(struct commit_list *list, int nr)
334 {
335 struct commit_list *p, *best;
336 int best_distance = -1;
337
338 best = list;
339 for (p = list; p; p = p->next) {
340 int distance;
341 unsigned flags = p->item->object.flags;
342
343 if (flags & TREESAME)
344 continue;
345 distance = weight(p);
346 if (nr - distance < distance)
347 distance = nr - distance;
348 if (distance > best_distance) {
349 best = p;
350 best_distance = distance;
351 }
352 }
353
354 return best;
355 }
356
357 struct commit_dist {
358 struct commit *commit;
359 int distance;
360 };
361
362 static int compare_commit_dist(const void *a_, const void *b_)
363 {
364 struct commit_dist *a, *b;
365
366 a = (struct commit_dist *)a_;
367 b = (struct commit_dist *)b_;
368 if (a->distance != b->distance)
369 return b->distance - a->distance; /* desc sort */
370 return hashcmp(a->commit->object.sha1, b->commit->object.sha1);
371 }
372
373 static struct commit_list *best_bisection_sorted(struct commit_list *list, int nr)
374 {
375 struct commit_list *p;
376 struct commit_dist *array = xcalloc(nr, sizeof(*array));
377 int cnt, i;
378
379 for (p = list, cnt = 0; p; p = p->next) {
380 int distance;
381 unsigned flags = p->item->object.flags;
382
383 if (flags & TREESAME)
384 continue;
385 distance = weight(p);
386 if (nr - distance < distance)
387 distance = nr - distance;
388 array[cnt].commit = p->item;
389 array[cnt].distance = distance;
390 cnt++;
391 }
392 qsort(array, cnt, sizeof(*array), compare_commit_dist);
393 for (p = list, i = 0; i < cnt; i++) {
394 struct name_decoration *r = xmalloc(sizeof(*r) + 100);
395 struct object *obj = &(array[i].commit->object);
396
397 sprintf(r->name, "dist=%d", array[i].distance);
398 r->next = add_decoration(&name_decoration, obj, r);
399 p->item = array[i].commit;
400 p = p->next;
401 }
402 if (p)
403 p->next = NULL;
404 free(array);
405 return list;
406 }
407
408 /*
409 * zero or positive weight is the number of interesting commits it can
410 * reach, including itself. Especially, weight = 0 means it does not
411 * reach any tree-changing commits (e.g. just above uninteresting one
412 * but traversal is with pathspec).
413 *
414 * weight = -1 means it has one parent and its distance is yet to
415 * be computed.
416 *
417 * weight = -2 means it has more than one parent and its distance is
418 * unknown. After running count_distance() first, they will get zero
419 * or positive distance.
420 */
421 static struct commit_list *do_find_bisection(struct commit_list *list,
422 int nr, int *weights,
423 int find_all)
424 {
425 int n, counted;
426 struct commit_list *p;
427
428 counted = 0;
429
430 for (n = 0, p = list; p; p = p->next) {
431 struct commit *commit = p->item;
432 unsigned flags = commit->object.flags;
433
434 p->item->util = &weights[n++];
435 switch (count_interesting_parents(commit)) {
436 case 0:
437 if (!(flags & TREESAME)) {
438 weight_set(p, 1);
439 counted++;
440 show_list("bisection 2 count one",
441 counted, nr, list);
442 }
443 /*
444 * otherwise, it is known not to reach any
445 * tree-changing commit and gets weight 0.
446 */
447 break;
448 case 1:
449 weight_set(p, -1);
450 break;
451 default:
452 weight_set(p, -2);
453 break;
454 }
455 }
456
457 show_list("bisection 2 initialize", counted, nr, list);
458
459 /*
460 * If you have only one parent in the resulting set
461 * then you can reach one commit more than that parent
462 * can reach. So we do not have to run the expensive
463 * count_distance() for single strand of pearls.
464 *
465 * However, if you have more than one parents, you cannot
466 * just add their distance and one for yourself, since
467 * they usually reach the same ancestor and you would
468 * end up counting them twice that way.
469 *
470 * So we will first count distance of merges the usual
471 * way, and then fill the blanks using cheaper algorithm.
472 */
473 for (p = list; p; p = p->next) {
474 if (p->item->object.flags & UNINTERESTING)
475 continue;
476 if (weight(p) != -2)
477 continue;
478 weight_set(p, count_distance(p));
479 clear_distance(list);
480
481 /* Does it happen to be at exactly half-way? */
482 if (!find_all && halfway(p, nr))
483 return p;
484 counted++;
485 }
486
487 show_list("bisection 2 count_distance", counted, nr, list);
488
489 while (counted < nr) {
490 for (p = list; p; p = p->next) {
491 struct commit_list *q;
492 unsigned flags = p->item->object.flags;
493
494 if (0 <= weight(p))
495 continue;
496 for (q = p->item->parents; q; q = q->next) {
497 if (q->item->object.flags & UNINTERESTING)
498 continue;
499 if (0 <= weight(q))
500 break;
501 }
502 if (!q)
503 continue;
504
505 /*
506 * weight for p is unknown but q is known.
507 * add one for p itself if p is to be counted,
508 * otherwise inherit it from q directly.
509 */
510 if (!(flags & TREESAME)) {
511 weight_set(p, weight(q)+1);
512 counted++;
513 show_list("bisection 2 count one",
514 counted, nr, list);
515 }
516 else
517 weight_set(p, weight(q));
518
519 /* Does it happen to be at exactly half-way? */
520 if (!find_all && halfway(p, nr))
521 return p;
522 }
523 }
524
525 show_list("bisection 2 counted all", counted, nr, list);
526
527 if (!find_all)
528 return best_bisection(list, nr);
529 else
530 return best_bisection_sorted(list, nr);
531 }
532
533 static struct commit_list *find_bisection(struct commit_list *list,
534 int *reaches, int *all,
535 int find_all)
536 {
537 int nr, on_list;
538 struct commit_list *p, *best, *next, *last;
539 int *weights;
540
541 show_list("bisection 2 entry", 0, 0, list);
542
543 /*
544 * Count the number of total and tree-changing items on the
545 * list, while reversing the list.
546 */
547 for (nr = on_list = 0, last = NULL, p = list;
548 p;
549 p = next) {
550 unsigned flags = p->item->object.flags;
551
552 next = p->next;
553 if (flags & UNINTERESTING)
554 continue;
555 p->next = last;
556 last = p;
557 if (!(flags & TREESAME))
558 nr++;
559 on_list++;
560 }
561 list = last;
562 show_list("bisection 2 sorted", 0, nr, list);
563
564 *all = nr;
565 weights = xcalloc(on_list, sizeof(*weights));
566
567 /* Do the real work of finding bisection commit. */
568 best = do_find_bisection(list, nr, weights, find_all);
569 if (best) {
570 if (!find_all)
571 best->next = NULL;
572 *reaches = weight(best);
573 }
574 free(weights);
575 return best;
576 }
577
578 int cmd_rev_list(int argc, const char **argv, const char *prefix)
579 {
580 struct commit_list *list;
581 int i;
582 int read_from_stdin = 0;
583 int bisect_show_vars = 0;
584 int bisect_find_all = 0;
585 int quiet = 0;
586
587 git_config(git_default_config, NULL);
588 init_revisions(&revs, prefix);
589 revs.abbrev = 0;
590 revs.commit_format = CMIT_FMT_UNSPECIFIED;
591 argc = setup_revisions(argc, argv, &revs, NULL);
592
593 quiet = DIFF_OPT_TST(&revs.diffopt, QUIET);
594 for (i = 1 ; i < argc; i++) {
595 const char *arg = argv[i];
596
597 if (!strcmp(arg, "--header")) {
598 revs.verbose_header = 1;
599 continue;
600 }
601 if (!strcmp(arg, "--timestamp")) {
602 show_timestamp = 1;
603 continue;
604 }
605 if (!strcmp(arg, "--bisect")) {
606 bisect_list = 1;
607 continue;
608 }
609 if (!strcmp(arg, "--bisect-all")) {
610 bisect_list = 1;
611 bisect_find_all = 1;
612 continue;
613 }
614 if (!strcmp(arg, "--bisect-vars")) {
615 bisect_list = 1;
616 bisect_show_vars = 1;
617 continue;
618 }
619 if (!strcmp(arg, "--stdin")) {
620 if (read_from_stdin++)
621 die("--stdin given twice?");
622 read_revisions_from_stdin(&revs);
623 continue;
624 }
625 usage(rev_list_usage);
626
627 }
628 if (revs.commit_format != CMIT_FMT_UNSPECIFIED) {
629 /* The command line has a --pretty */
630 hdr_termination = '\n';
631 if (revs.commit_format == CMIT_FMT_ONELINE)
632 header_prefix = "";
633 else
634 header_prefix = "commit ";
635 }
636 else if (revs.verbose_header)
637 /* Only --header was specified */
638 revs.commit_format = CMIT_FMT_RAW;
639
640 list = revs.commits;
641
642 if ((!list &&
643 (!(revs.tag_objects||revs.tree_objects||revs.blob_objects) &&
644 !revs.pending.nr)) ||
645 revs.diff)
646 usage(rev_list_usage);
647
648 save_commit_buffer = revs.verbose_header ||
649 revs.grep_filter.pattern_list;
650 if (bisect_list)
651 revs.limited = 1;
652
653 if (prepare_revision_walk(&revs))
654 die("revision walk setup failed");
655 if (revs.tree_objects)
656 mark_edges_uninteresting(revs.commits, &revs, show_edge);
657
658 if (bisect_list) {
659 int reaches = reaches, all = all;
660
661 revs.commits = find_bisection(revs.commits, &reaches, &all,
662 bisect_find_all);
663 if (bisect_show_vars) {
664 int cnt;
665 char hex[41];
666 if (!revs.commits)
667 return 1;
668 /*
669 * revs.commits can reach "reaches" commits among
670 * "all" commits. If it is good, then there are
671 * (all-reaches) commits left to be bisected.
672 * On the other hand, if it is bad, then the set
673 * to bisect is "reaches".
674 * A bisect set of size N has (N-1) commits further
675 * to test, as we already know one bad one.
676 */
677 cnt = all - reaches;
678 if (cnt < reaches)
679 cnt = reaches;
680 strcpy(hex, sha1_to_hex(revs.commits->item->object.sha1));
681
682 if (bisect_find_all) {
683 traverse_commit_list(&revs, show_commit, show_object);
684 printf("------\n");
685 }
686
687 printf("bisect_rev=%s\n"
688 "bisect_nr=%d\n"
689 "bisect_good=%d\n"
690 "bisect_bad=%d\n"
691 "bisect_all=%d\n",
692 hex,
693 cnt - 1,
694 all - reaches - 1,
695 reaches - 1,
696 all);
697 return 0;
698 }
699 }
700
701 traverse_commit_list(&revs,
702 quiet ? finish_commit : show_commit,
703 quiet ? finish_object : show_object);
704
705 return 0;
706 }