Provide git_config with a callback-data parameter
[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
14 /* bits #0-15 in revision.h */
15
16 #define COUNTED (1u<<16)
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 " --branches\n"
29 " --tags\n"
30 " --remotes\n"
31 " --stdin\n"
32 " --quiet\n"
33 " ordering output:\n"
34 " --topo-order\n"
35 " --date-order\n"
36 " --reverse\n"
37 " formatting output:\n"
38 " --parents\n"
39 " --objects | --objects-edge\n"
40 " --unpacked\n"
41 " --header | --pretty\n"
42 " --abbrev=nr | --no-abbrev\n"
43 " --abbrev-commit\n"
44 " --left-right\n"
45 " special purpose:\n"
46 " --bisect\n"
47 " --bisect-vars\n"
48 " --bisect-all"
49 ;
50
51 static struct rev_info revs;
52
53 static int bisect_list;
54 static int show_timestamp;
55 static int hdr_termination;
56 static const char *header_prefix;
57
58 static void finish_commit(struct commit *commit);
59 static void show_commit(struct commit *commit)
60 {
61 if (show_timestamp)
62 printf("%lu ", commit->date);
63 if (header_prefix)
64 fputs(header_prefix, stdout);
65 if (commit->object.flags & BOUNDARY)
66 putchar('-');
67 else if (commit->object.flags & UNINTERESTING)
68 putchar('^');
69 else if (revs.left_right) {
70 if (commit->object.flags & SYMMETRIC_LEFT)
71 putchar('<');
72 else
73 putchar('>');
74 }
75 if (revs.abbrev_commit && revs.abbrev)
76 fputs(find_unique_abbrev(commit->object.sha1, revs.abbrev),
77 stdout);
78 else
79 fputs(sha1_to_hex(commit->object.sha1), stdout);
80 if (revs.parents) {
81 struct commit_list *parents = commit->parents;
82 while (parents) {
83 printf(" %s", sha1_to_hex(parents->item->object.sha1));
84 parents = parents->next;
85 }
86 }
87 show_decorations(commit);
88 if (revs.commit_format == CMIT_FMT_ONELINE)
89 putchar(' ');
90 else
91 putchar('\n');
92
93 if (revs.verbose_header && commit->buffer) {
94 struct strbuf buf;
95 strbuf_init(&buf, 0);
96 pretty_print_commit(revs.commit_format, commit,
97 &buf, revs.abbrev, NULL, NULL,
98 revs.date_mode, 0);
99 if (buf.len)
100 printf("%s%c", buf.buf, hdr_termination);
101 strbuf_release(&buf);
102 }
103 maybe_flush_or_die(stdout, "stdout");
104 finish_commit(commit);
105 }
106
107 static void finish_commit(struct commit *commit)
108 {
109 if (commit->parents) {
110 free_commit_list(commit->parents);
111 commit->parents = NULL;
112 }
113 free(commit->buffer);
114 commit->buffer = NULL;
115 }
116
117 static void finish_object(struct object_array_entry *p)
118 {
119 if (p->item->type == OBJ_BLOB && !has_sha1_file(p->item->sha1))
120 die("missing blob object '%s'", sha1_to_hex(p->item->sha1));
121 }
122
123 static void show_object(struct object_array_entry *p)
124 {
125 /* An object with name "foo\n0000000..." can be used to
126 * confuse downstream git-pack-objects very badly.
127 */
128 const char *ep = strchr(p->name, '\n');
129
130 finish_object(p);
131 if (ep) {
132 printf("%s %.*s\n", sha1_to_hex(p->item->sha1),
133 (int) (ep - p->name),
134 p->name);
135 }
136 else
137 printf("%s %s\n", sha1_to_hex(p->item->sha1), p->name);
138 }
139
140 static void show_edge(struct commit *commit)
141 {
142 printf("-%s\n", sha1_to_hex(commit->object.sha1));
143 }
144
145 /*
146 * This is a truly stupid algorithm, but it's only
147 * used for bisection, and we just don't care enough.
148 *
149 * We care just barely enough to avoid recursing for
150 * non-merge entries.
151 */
152 static int count_distance(struct commit_list *entry)
153 {
154 int nr = 0;
155
156 while (entry) {
157 struct commit *commit = entry->item;
158 struct commit_list *p;
159
160 if (commit->object.flags & (UNINTERESTING | COUNTED))
161 break;
162 if (!(commit->object.flags & TREESAME))
163 nr++;
164 commit->object.flags |= COUNTED;
165 p = commit->parents;
166 entry = p;
167 if (p) {
168 p = p->next;
169 while (p) {
170 nr += count_distance(p);
171 p = p->next;
172 }
173 }
174 }
175
176 return nr;
177 }
178
179 static void clear_distance(struct commit_list *list)
180 {
181 while (list) {
182 struct commit *commit = list->item;
183 commit->object.flags &= ~COUNTED;
184 list = list->next;
185 }
186 }
187
188 #define DEBUG_BISECT 0
189
190 static inline int weight(struct commit_list *elem)
191 {
192 return *((int*)(elem->item->util));
193 }
194
195 static inline void weight_set(struct commit_list *elem, int weight)
196 {
197 *((int*)(elem->item->util)) = weight;
198 }
199
200 static int count_interesting_parents(struct commit *commit)
201 {
202 struct commit_list *p;
203 int count;
204
205 for (count = 0, p = commit->parents; p; p = p->next) {
206 if (p->item->object.flags & UNINTERESTING)
207 continue;
208 count++;
209 }
210 return count;
211 }
212
213 static inline int halfway(struct commit_list *p, int nr)
214 {
215 /*
216 * Don't short-cut something we are not going to return!
217 */
218 if (p->item->object.flags & TREESAME)
219 return 0;
220 if (DEBUG_BISECT)
221 return 0;
222 /*
223 * 2 and 3 are halfway of 5.
224 * 3 is halfway of 6 but 2 and 4 are not.
225 */
226 switch (2 * weight(p) - nr) {
227 case -1: case 0: case 1:
228 return 1;
229 default:
230 return 0;
231 }
232 }
233
234 #if !DEBUG_BISECT
235 #define show_list(a,b,c,d) do { ; } while (0)
236 #else
237 static void show_list(const char *debug, int counted, int nr,
238 struct commit_list *list)
239 {
240 struct commit_list *p;
241
242 fprintf(stderr, "%s (%d/%d)\n", debug, counted, nr);
243
244 for (p = list; p; p = p->next) {
245 struct commit_list *pp;
246 struct commit *commit = p->item;
247 unsigned flags = commit->object.flags;
248 enum object_type type;
249 unsigned long size;
250 char *buf = read_sha1_file(commit->object.sha1, &type, &size);
251 char *ep, *sp;
252
253 fprintf(stderr, "%c%c%c ",
254 (flags & TREESAME) ? ' ' : 'T',
255 (flags & UNINTERESTING) ? 'U' : ' ',
256 (flags & COUNTED) ? 'C' : ' ');
257 if (commit->util)
258 fprintf(stderr, "%3d", weight(p));
259 else
260 fprintf(stderr, "---");
261 fprintf(stderr, " %.*s", 8, sha1_to_hex(commit->object.sha1));
262 for (pp = commit->parents; pp; pp = pp->next)
263 fprintf(stderr, " %.*s", 8,
264 sha1_to_hex(pp->item->object.sha1));
265
266 sp = strstr(buf, "\n\n");
267 if (sp) {
268 sp += 2;
269 for (ep = sp; *ep && *ep != '\n'; ep++)
270 ;
271 fprintf(stderr, " %.*s", (int)(ep - sp), sp);
272 }
273 fprintf(stderr, "\n");
274 }
275 }
276 #endif /* DEBUG_BISECT */
277
278 static struct commit_list *best_bisection(struct commit_list *list, int nr)
279 {
280 struct commit_list *p, *best;
281 int best_distance = -1;
282
283 best = list;
284 for (p = list; p; p = p->next) {
285 int distance;
286 unsigned flags = p->item->object.flags;
287
288 if (flags & TREESAME)
289 continue;
290 distance = weight(p);
291 if (nr - distance < distance)
292 distance = nr - distance;
293 if (distance > best_distance) {
294 best = p;
295 best_distance = distance;
296 }
297 }
298
299 return best;
300 }
301
302 struct commit_dist {
303 struct commit *commit;
304 int distance;
305 };
306
307 static int compare_commit_dist(const void *a_, const void *b_)
308 {
309 struct commit_dist *a, *b;
310
311 a = (struct commit_dist *)a_;
312 b = (struct commit_dist *)b_;
313 if (a->distance != b->distance)
314 return b->distance - a->distance; /* desc sort */
315 return hashcmp(a->commit->object.sha1, b->commit->object.sha1);
316 }
317
318 static struct commit_list *best_bisection_sorted(struct commit_list *list, int nr)
319 {
320 struct commit_list *p;
321 struct commit_dist *array = xcalloc(nr, sizeof(*array));
322 int cnt, i;
323
324 for (p = list, cnt = 0; p; p = p->next) {
325 int distance;
326 unsigned flags = p->item->object.flags;
327
328 if (flags & TREESAME)
329 continue;
330 distance = weight(p);
331 if (nr - distance < distance)
332 distance = nr - distance;
333 array[cnt].commit = p->item;
334 array[cnt].distance = distance;
335 cnt++;
336 }
337 qsort(array, cnt, sizeof(*array), compare_commit_dist);
338 for (p = list, i = 0; i < cnt; i++) {
339 struct name_decoration *r = xmalloc(sizeof(*r) + 100);
340 struct object *obj = &(array[i].commit->object);
341
342 sprintf(r->name, "dist=%d", array[i].distance);
343 r->next = add_decoration(&name_decoration, obj, r);
344 p->item = array[i].commit;
345 p = p->next;
346 }
347 if (p)
348 p->next = NULL;
349 free(array);
350 return list;
351 }
352
353 /*
354 * zero or positive weight is the number of interesting commits it can
355 * reach, including itself. Especially, weight = 0 means it does not
356 * reach any tree-changing commits (e.g. just above uninteresting one
357 * but traversal is with pathspec).
358 *
359 * weight = -1 means it has one parent and its distance is yet to
360 * be computed.
361 *
362 * weight = -2 means it has more than one parent and its distance is
363 * unknown. After running count_distance() first, they will get zero
364 * or positive distance.
365 */
366 static struct commit_list *do_find_bisection(struct commit_list *list,
367 int nr, int *weights,
368 int find_all)
369 {
370 int n, counted;
371 struct commit_list *p;
372
373 counted = 0;
374
375 for (n = 0, p = list; p; p = p->next) {
376 struct commit *commit = p->item;
377 unsigned flags = commit->object.flags;
378
379 p->item->util = &weights[n++];
380 switch (count_interesting_parents(commit)) {
381 case 0:
382 if (!(flags & TREESAME)) {
383 weight_set(p, 1);
384 counted++;
385 show_list("bisection 2 count one",
386 counted, nr, list);
387 }
388 /*
389 * otherwise, it is known not to reach any
390 * tree-changing commit and gets weight 0.
391 */
392 break;
393 case 1:
394 weight_set(p, -1);
395 break;
396 default:
397 weight_set(p, -2);
398 break;
399 }
400 }
401
402 show_list("bisection 2 initialize", counted, nr, list);
403
404 /*
405 * If you have only one parent in the resulting set
406 * then you can reach one commit more than that parent
407 * can reach. So we do not have to run the expensive
408 * count_distance() for single strand of pearls.
409 *
410 * However, if you have more than one parents, you cannot
411 * just add their distance and one for yourself, since
412 * they usually reach the same ancestor and you would
413 * end up counting them twice that way.
414 *
415 * So we will first count distance of merges the usual
416 * way, and then fill the blanks using cheaper algorithm.
417 */
418 for (p = list; p; p = p->next) {
419 if (p->item->object.flags & UNINTERESTING)
420 continue;
421 if (weight(p) != -2)
422 continue;
423 weight_set(p, count_distance(p));
424 clear_distance(list);
425
426 /* Does it happen to be at exactly half-way? */
427 if (!find_all && halfway(p, nr))
428 return p;
429 counted++;
430 }
431
432 show_list("bisection 2 count_distance", counted, nr, list);
433
434 while (counted < nr) {
435 for (p = list; p; p = p->next) {
436 struct commit_list *q;
437 unsigned flags = p->item->object.flags;
438
439 if (0 <= weight(p))
440 continue;
441 for (q = p->item->parents; q; q = q->next) {
442 if (q->item->object.flags & UNINTERESTING)
443 continue;
444 if (0 <= weight(q))
445 break;
446 }
447 if (!q)
448 continue;
449
450 /*
451 * weight for p is unknown but q is known.
452 * add one for p itself if p is to be counted,
453 * otherwise inherit it from q directly.
454 */
455 if (!(flags & TREESAME)) {
456 weight_set(p, weight(q)+1);
457 counted++;
458 show_list("bisection 2 count one",
459 counted, nr, list);
460 }
461 else
462 weight_set(p, weight(q));
463
464 /* Does it happen to be at exactly half-way? */
465 if (!find_all && halfway(p, nr))
466 return p;
467 }
468 }
469
470 show_list("bisection 2 counted all", counted, nr, list);
471
472 if (!find_all)
473 return best_bisection(list, nr);
474 else
475 return best_bisection_sorted(list, nr);
476 }
477
478 static struct commit_list *find_bisection(struct commit_list *list,
479 int *reaches, int *all,
480 int find_all)
481 {
482 int nr, on_list;
483 struct commit_list *p, *best, *next, *last;
484 int *weights;
485
486 show_list("bisection 2 entry", 0, 0, list);
487
488 /*
489 * Count the number of total and tree-changing items on the
490 * list, while reversing the list.
491 */
492 for (nr = on_list = 0, last = NULL, p = list;
493 p;
494 p = next) {
495 unsigned flags = p->item->object.flags;
496
497 next = p->next;
498 if (flags & UNINTERESTING)
499 continue;
500 p->next = last;
501 last = p;
502 if (!(flags & TREESAME))
503 nr++;
504 on_list++;
505 }
506 list = last;
507 show_list("bisection 2 sorted", 0, nr, list);
508
509 *all = nr;
510 weights = xcalloc(on_list, sizeof(*weights));
511
512 /* Do the real work of finding bisection commit. */
513 best = do_find_bisection(list, nr, weights, find_all);
514 if (best) {
515 if (!find_all)
516 best->next = NULL;
517 *reaches = weight(best);
518 }
519 free(weights);
520 return best;
521 }
522
523 static void read_revisions_from_stdin(struct rev_info *revs)
524 {
525 char line[1000];
526
527 while (fgets(line, sizeof(line), stdin) != NULL) {
528 int len = strlen(line);
529 if (len && line[len - 1] == '\n')
530 line[--len] = 0;
531 if (!len)
532 break;
533 if (line[0] == '-')
534 die("options not supported in --stdin mode");
535 if (handle_revision_arg(line, revs, 0, 1))
536 die("bad revision '%s'", line);
537 }
538 }
539
540 int cmd_rev_list(int argc, const char **argv, const char *prefix)
541 {
542 struct commit_list *list;
543 int i;
544 int read_from_stdin = 0;
545 int bisect_show_vars = 0;
546 int bisect_find_all = 0;
547 int quiet = 0;
548
549 git_config(git_default_config, NULL);
550 init_revisions(&revs, prefix);
551 revs.abbrev = 0;
552 revs.commit_format = CMIT_FMT_UNSPECIFIED;
553 argc = setup_revisions(argc, argv, &revs, NULL);
554
555 for (i = 1 ; i < argc; i++) {
556 const char *arg = argv[i];
557
558 if (!strcmp(arg, "--header")) {
559 revs.verbose_header = 1;
560 continue;
561 }
562 if (!strcmp(arg, "--timestamp")) {
563 show_timestamp = 1;
564 continue;
565 }
566 if (!strcmp(arg, "--bisect")) {
567 bisect_list = 1;
568 continue;
569 }
570 if (!strcmp(arg, "--bisect-all")) {
571 bisect_list = 1;
572 bisect_find_all = 1;
573 continue;
574 }
575 if (!strcmp(arg, "--bisect-vars")) {
576 bisect_list = 1;
577 bisect_show_vars = 1;
578 continue;
579 }
580 if (!strcmp(arg, "--stdin")) {
581 if (read_from_stdin++)
582 die("--stdin given twice?");
583 read_revisions_from_stdin(&revs);
584 continue;
585 }
586 if (!strcmp(arg, "--quiet")) {
587 quiet = 1;
588 continue;
589 }
590 usage(rev_list_usage);
591
592 }
593 if (revs.commit_format != CMIT_FMT_UNSPECIFIED) {
594 /* The command line has a --pretty */
595 hdr_termination = '\n';
596 if (revs.commit_format == CMIT_FMT_ONELINE)
597 header_prefix = "";
598 else
599 header_prefix = "commit ";
600 }
601 else if (revs.verbose_header)
602 /* Only --header was specified */
603 revs.commit_format = CMIT_FMT_RAW;
604
605 list = revs.commits;
606
607 if ((!list &&
608 (!(revs.tag_objects||revs.tree_objects||revs.blob_objects) &&
609 !revs.pending.nr)) ||
610 revs.diff)
611 usage(rev_list_usage);
612
613 save_commit_buffer = revs.verbose_header || revs.grep_filter;
614 if (bisect_list)
615 revs.limited = 1;
616
617 if (prepare_revision_walk(&revs))
618 die("revision walk setup failed");
619 if (revs.tree_objects)
620 mark_edges_uninteresting(revs.commits, &revs, show_edge);
621
622 if (bisect_list) {
623 int reaches = reaches, all = all;
624
625 revs.commits = find_bisection(revs.commits, &reaches, &all,
626 bisect_find_all);
627 if (bisect_show_vars) {
628 int cnt;
629 char hex[41];
630 if (!revs.commits)
631 return 1;
632 /*
633 * revs.commits can reach "reaches" commits among
634 * "all" commits. If it is good, then there are
635 * (all-reaches) commits left to be bisected.
636 * On the other hand, if it is bad, then the set
637 * to bisect is "reaches".
638 * A bisect set of size N has (N-1) commits further
639 * to test, as we already know one bad one.
640 */
641 cnt = all - reaches;
642 if (cnt < reaches)
643 cnt = reaches;
644 strcpy(hex, sha1_to_hex(revs.commits->item->object.sha1));
645
646 if (bisect_find_all) {
647 traverse_commit_list(&revs, show_commit, show_object);
648 printf("------\n");
649 }
650
651 printf("bisect_rev=%s\n"
652 "bisect_nr=%d\n"
653 "bisect_good=%d\n"
654 "bisect_bad=%d\n"
655 "bisect_all=%d\n",
656 hex,
657 cnt - 1,
658 all - reaches - 1,
659 reaches - 1,
660 all);
661 return 0;
662 }
663 }
664
665 traverse_commit_list(&revs,
666 quiet ? finish_commit : show_commit,
667 quiet ? finish_object : show_object);
668
669 return 0;
670 }