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