1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
|
#include "cache.h"
#include "commit.h"
#include "diff.h"
#include "revision.h"
#include "refs.h"
#include "list-objects.h"
#include "quote.h"
#include "sha1-lookup.h"
#include "run-command.h"
#include "log-tree.h"
#include "bisect.h"
struct sha1_array {
unsigned char (*sha1)[20];
int sha1_nr;
int sha1_alloc;
int sorted;
};
static struct sha1_array good_revs;
static struct sha1_array skipped_revs;
static const unsigned char *current_bad_sha1;
struct argv_array {
const char **argv;
int argv_nr;
int argv_alloc;
};
static const char *argv_checkout[] = {"checkout", "-q", NULL, "--", NULL};
static const char *argv_show_branch[] = {"show-branch", NULL, NULL};
/* bits #0-15 in revision.h */
#define COUNTED (1u<<16)
/*
* This is a truly stupid algorithm, but it's only
* used for bisection, and we just don't care enough.
*
* We care just barely enough to avoid recursing for
* non-merge entries.
*/
static int count_distance(struct commit_list *entry)
{
int nr = 0;
while (entry) {
struct commit *commit = entry->item;
struct commit_list *p;
if (commit->object.flags & (UNINTERESTING | COUNTED))
break;
if (!(commit->object.flags & TREESAME))
nr++;
commit->object.flags |= COUNTED;
p = commit->parents;
entry = p;
if (p) {
p = p->next;
while (p) {
nr += count_distance(p);
p = p->next;
}
}
}
return nr;
}
static void clear_distance(struct commit_list *list)
{
while (list) {
struct commit *commit = list->item;
commit->object.flags &= ~COUNTED;
list = list->next;
}
}
#define DEBUG_BISECT 0
static inline int weight(struct commit_list *elem)
{
return *((int*)(elem->item->util));
}
static inline void weight_set(struct commit_list *elem, int weight)
{
*((int*)(elem->item->util)) = weight;
}
static int count_interesting_parents(struct commit *commit)
{
struct commit_list *p;
int count;
for (count = 0, p = commit->parents; p; p = p->next) {
if (p->item->object.flags & UNINTERESTING)
continue;
count++;
}
return count;
}
static inline int halfway(struct commit_list *p, int nr)
{
/*
* Don't short-cut something we are not going to return!
*/
if (p->item->object.flags & TREESAME)
return 0;
if (DEBUG_BISECT)
return 0;
/*
* 2 and 3 are halfway of 5.
* 3 is halfway of 6 but 2 and 4 are not.
*/
switch (2 * weight(p) - nr) {
case -1: case 0: case 1:
return 1;
default:
return 0;
}
}
#if !DEBUG_BISECT
#define show_list(a,b,c,d) do { ; } while (0)
#else
static void show_list(const char *debug, int counted, int nr,
struct commit_list *list)
{
struct commit_list *p;
fprintf(stderr, "%s (%d/%d)\n", debug, counted, nr);
for (p = list; p; p = p->next) {
struct commit_list *pp;
struct commit *commit = p->item;
unsigned flags = commit->object.flags;
enum object_type type;
unsigned long size;
char *buf = read_sha1_file(commit->object.sha1, &type, &size);
char *ep, *sp;
fprintf(stderr, "%c%c%c ",
(flags & TREESAME) ? ' ' : 'T',
(flags & UNINTERESTING) ? 'U' : ' ',
(flags & COUNTED) ? 'C' : ' ');
if (commit->util)
fprintf(stderr, "%3d", weight(p));
else
fprintf(stderr, "---");
fprintf(stderr, " %.*s", 8, sha1_to_hex(commit->object.sha1));
for (pp = commit->parents; pp; pp = pp->next)
fprintf(stderr, " %.*s", 8,
sha1_to_hex(pp->item->object.sha1));
sp = strstr(buf, "\n\n");
if (sp) {
sp += 2;
for (ep = sp; *ep && *ep != '\n'; ep++)
;
fprintf(stderr, " %.*s", (int)(ep - sp), sp);
}
fprintf(stderr, "\n");
}
}
#endif /* DEBUG_BISECT */
static struct commit_list *best_bisection(struct commit_list *list, int nr)
{
struct commit_list *p, *best;
int best_distance = -1;
best = list;
for (p = list; p; p = p->next) {
int distance;
unsigned flags = p->item->object.flags;
if (flags & TREESAME)
continue;
distance = weight(p);
if (nr - distance < distance)
distance = nr - distance;
if (distance > best_distance) {
best = p;
best_distance = distance;
}
}
return best;
}
struct commit_dist {
struct commit *commit;
int distance;
};
static int compare_commit_dist(const void *a_, const void *b_)
{
struct commit_dist *a, *b;
a = (struct commit_dist *)a_;
b = (struct commit_dist *)b_;
if (a->distance != b->distance)
return b->distance - a->distance; /* desc sort */
return hashcmp(a->commit->object.sha1, b->commit->object.sha1);
}
static struct commit_list *best_bisection_sorted(struct commit_list *list, int nr)
{
struct commit_list *p;
struct commit_dist *array = xcalloc(nr, sizeof(*array));
int cnt, i;
for (p = list, cnt = 0; p; p = p->next) {
int distance;
unsigned flags = p->item->object.flags;
if (flags & TREESAME)
continue;
distance = weight(p);
if (nr - distance < distance)
distance = nr - distance;
array[cnt].commit = p->item;
array[cnt].distance = distance;
cnt++;
}
qsort(array, cnt, sizeof(*array), compare_commit_dist);
for (p = list, i = 0; i < cnt; i++) {
struct name_decoration *r = xmalloc(sizeof(*r) + 100);
struct object *obj = &(array[i].commit->object);
sprintf(r->name, "dist=%d", array[i].distance);
r->next = add_decoration(&name_decoration, obj, r);
p->item = array[i].commit;
p = p->next;
}
if (p)
p->next = NULL;
free(array);
return list;
}
/*
* zero or positive weight is the number of interesting commits it can
* reach, including itself. Especially, weight = 0 means it does not
* reach any tree-changing commits (e.g. just above uninteresting one
* but traversal is with pathspec).
*
* weight = -1 means it has one parent and its distance is yet to
* be computed.
*
* weight = -2 means it has more than one parent and its distance is
* unknown. After running count_distance() first, they will get zero
* or positive distance.
*/
static struct commit_list *do_find_bisection(struct commit_list *list,
int nr, int *weights,
int find_all)
{
int n, counted;
struct commit_list *p;
counted = 0;
for (n = 0, p = list; p; p = p->next) {
struct commit *commit = p->item;
unsigned flags = commit->object.flags;
p->item->util = &weights[n++];
switch (count_interesting_parents(commit)) {
case 0:
if (!(flags & TREESAME)) {
weight_set(p, 1);
counted++;
show_list("bisection 2 count one",
counted, nr, list);
}
/*
* otherwise, it is known not to reach any
* tree-changing commit and gets weight 0.
*/
break;
case 1:
weight_set(p, -1);
break;
default:
weight_set(p, -2);
break;
}
}
show_list("bisection 2 initialize", counted, nr, list);
/*
* If you have only one parent in the resulting set
* then you can reach one commit more than that parent
* can reach. So we do not have to run the expensive
* count_distance() for single strand of pearls.
*
* However, if you have more than one parents, you cannot
* just add their distance and one for yourself, since
* they usually reach the same ancestor and you would
* end up counting them twice that way.
*
* So we will first count distance of merges the usual
* way, and then fill the blanks using cheaper algorithm.
*/
for (p = list; p; p = p->next) {
if (p->item->object.flags & UNINTERESTING)
continue;
if (weight(p) != -2)
continue;
weight_set(p, count_distance(p));
clear_distance(list);
/* Does it happen to be at exactly half-way? */
if (!find_all && halfway(p, nr))
return p;
counted++;
}
show_list("bisection 2 count_distance", counted, nr, list);
while (counted < nr) {
for (p = list; p; p = p->next) {
struct commit_list *q;
unsigned flags = p->item->object.flags;
if (0 <= weight(p))
continue;
for (q = p->item->parents; q; q = q->next) {
if (q->item->object.flags & UNINTERESTING)
continue;
if (0 <= weight(q))
break;
}
if (!q)
continue;
/*
* weight for p is unknown but q is known.
* add one for p itself if p is to be counted,
* otherwise inherit it from q directly.
*/
if (!(flags & TREESAME)) {
weight_set(p, weight(q)+1);
counted++;
show_list("bisection 2 count one",
counted, nr, list);
}
else
weight_set(p, weight(q));
/* Does it happen to be at exactly half-way? */
if (!find_all && halfway(p, nr))
return p;
}
}
show_list("bisection 2 counted all", counted, nr, list);
if (!find_all)
return best_bisection(list, nr);
else
return best_bisection_sorted(list, nr);
}
struct commit_list *find_bisection(struct commit_list *list,
int *reaches, int *all,
int find_all)
{
int nr, on_list;
struct commit_list *p, *best, *next, *last;
int *weights;
show_list("bisection 2 entry", 0, 0, list);
/*
* Count the number of total and tree-changing items on the
* list, while reversing the list.
*/
for (nr = on_list = 0, last = NULL, p = list;
p;
p = next) {
unsigned flags = p->item->object.flags;
next = p->next;
if (flags & UNINTERESTING)
continue;
p->next = last;
last = p;
if (!(flags & TREESAME))
nr++;
on_list++;
}
list = last;
show_list("bisection 2 sorted", 0, nr, list);
*all = nr;
weights = xcalloc(on_list, sizeof(*weights));
/* Do the real work of finding bisection commit. */
best = do_find_bisection(list, nr, weights, find_all);
if (best) {
if (!find_all)
best->next = NULL;
*reaches = weight(best);
}
free(weights);
return best;
}
static void argv_array_push(struct argv_array *array, const char *string)
{
ALLOC_GROW(array->argv, array->argv_nr + 1, array->argv_alloc);
array->argv[array->argv_nr++] = string;
}
static void argv_array_push_sha1(struct argv_array *array,
const unsigned char *sha1,
const char *format)
{
struct strbuf buf = STRBUF_INIT;
strbuf_addf(&buf, format, sha1_to_hex(sha1));
argv_array_push(array, strbuf_detach(&buf, NULL));
}
static void sha1_array_push(struct sha1_array *array,
const unsigned char *sha1)
{
ALLOC_GROW(array->sha1, array->sha1_nr + 1, array->sha1_alloc);
hashcpy(array->sha1[array->sha1_nr++], sha1);
}
static int register_ref(const char *refname, const unsigned char *sha1,
int flags, void *cb_data)
{
if (!strcmp(refname, "bad")) {
current_bad_sha1 = sha1;
} else if (!prefixcmp(refname, "good-")) {
sha1_array_push(&good_revs, sha1);
} else if (!prefixcmp(refname, "skip-")) {
sha1_array_push(&skipped_revs, sha1);
}
return 0;
}
static int read_bisect_refs(void)
{
return for_each_ref_in("refs/bisect/", register_ref, NULL);
}
void read_bisect_paths(struct argv_array *array)
{
struct strbuf str = STRBUF_INIT;
const char *filename = git_path("BISECT_NAMES");
FILE *fp = fopen(filename, "r");
if (!fp)
die("Could not open file '%s': %s", filename, strerror(errno));
while (strbuf_getline(&str, fp, '\n') != EOF) {
char *quoted;
int res;
strbuf_trim(&str);
quoted = strbuf_detach(&str, NULL);
res = sq_dequote_to_argv(quoted, &array->argv,
&array->argv_nr, &array->argv_alloc);
if (res)
die("Badly quoted content in file '%s': %s",
filename, quoted);
}
strbuf_release(&str);
fclose(fp);
}
static int array_cmp(const void *a, const void *b)
{
return hashcmp(a, b);
}
static void sort_sha1_array(struct sha1_array *array)
{
qsort(array->sha1, array->sha1_nr, sizeof(*array->sha1), array_cmp);
array->sorted = 1;
}
static const unsigned char *sha1_access(size_t index, void *table)
{
unsigned char (*array)[20] = table;
return array[index];
}
static int lookup_sha1_array(struct sha1_array *array,
const unsigned char *sha1)
{
if (!array->sorted)
sort_sha1_array(array);
return sha1_pos(sha1, array->sha1, array->sha1_nr, sha1_access);
}
static char *join_sha1_array_hex(struct sha1_array *array, char delim)
{
struct strbuf joined_hexs = STRBUF_INIT;
int i;
for (i = 0; i < array->sha1_nr; i++) {
strbuf_addstr(&joined_hexs, sha1_to_hex(array->sha1[i]));
if (i + 1 < array->sha1_nr)
strbuf_addch(&joined_hexs, delim);
}
return strbuf_detach(&joined_hexs, NULL);
}
struct commit_list *filter_skipped(struct commit_list *list,
struct commit_list **tried,
int show_all)
{
struct commit_list *filtered = NULL, **f = &filtered;
*tried = NULL;
if (!skipped_revs.sha1_nr)
return list;
while (list) {
struct commit_list *next = list->next;
list->next = NULL;
if (0 <= lookup_sha1_array(&skipped_revs,
list->item->object.sha1)) {
/* Move current to tried list */
*tried = list;
tried = &list->next;
} else {
if (!show_all)
return list;
/* Move current to filtered list */
*f = list;
f = &list->next;
}
list = next;
}
return filtered;
}
static void bisect_rev_setup(struct rev_info *revs, const char *prefix,
const char *bad_format, const char *good_format,
int read_paths)
{
struct argv_array rev_argv = { NULL, 0, 0 };
int i;
init_revisions(revs, prefix);
revs->abbrev = 0;
revs->commit_format = CMIT_FMT_UNSPECIFIED;
/* rev_argv.argv[0] will be ignored by setup_revisions */
argv_array_push(&rev_argv, xstrdup("bisect_rev_setup"));
argv_array_push_sha1(&rev_argv, current_bad_sha1, bad_format);
for (i = 0; i < good_revs.sha1_nr; i++)
argv_array_push_sha1(&rev_argv, good_revs.sha1[i],
good_format);
argv_array_push(&rev_argv, xstrdup("--"));
if (read_paths)
read_bisect_paths(&rev_argv);
argv_array_push(&rev_argv, NULL);
setup_revisions(rev_argv.argv_nr, rev_argv.argv, revs, NULL);
}
static void bisect_common(struct rev_info *revs)
{
if (prepare_revision_walk(revs))
die("revision walk setup failed");
if (revs->tree_objects)
mark_edges_uninteresting(revs->commits, revs, NULL);
}
static void exit_if_skipped_commits(struct commit_list *tried,
const unsigned char *bad)
{
if (!tried)
return;
printf("There are only 'skip'ped commits left to test.\n"
"The first bad commit could be any of:\n");
print_commit_list(tried, "%s\n", "%s\n");
if (bad)
printf("%s\n", sha1_to_hex(bad));
printf("We cannot bisect more!\n");
exit(2);
}
static int is_expected_rev(const unsigned char *sha1)
{
const char *filename = git_path("BISECT_EXPECTED_REV");
struct stat st;
struct strbuf str = STRBUF_INIT;
FILE *fp;
int res = 0;
if (stat(filename, &st) || !S_ISREG(st.st_mode))
return 0;
fp = fopen(filename, "r");
if (!fp)
return 0;
if (strbuf_getline(&str, fp, '\n') != EOF)
res = !strcmp(str.buf, sha1_to_hex(sha1));
strbuf_release(&str);
fclose(fp);
return res;
}
static void mark_expected_rev(char *bisect_rev_hex)
{
int len = strlen(bisect_rev_hex);
const char *filename = git_path("BISECT_EXPECTED_REV");
int fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY, 0600);
if (fd < 0)
die("could not create file '%s': %s",
filename, strerror(errno));
bisect_rev_hex[len] = '\n';
write_or_die(fd, bisect_rev_hex, len + 1);
bisect_rev_hex[len] = '\0';
if (close(fd) < 0)
die("closing file %s: %s", filename, strerror(errno));
}
static int bisect_checkout(char *bisect_rev_hex)
{
int res;
mark_expected_rev(bisect_rev_hex);
argv_checkout[2] = bisect_rev_hex;
res = run_command_v_opt(argv_checkout, RUN_GIT_CMD);
if (res)
exit(res);
argv_show_branch[1] = bisect_rev_hex;
return run_command_v_opt(argv_show_branch, RUN_GIT_CMD);
}
static struct commit *get_commit_reference(const unsigned char *sha1)
{
struct commit *r = lookup_commit_reference(sha1);
if (!r)
die("Not a valid commit name %s", sha1_to_hex(sha1));
return r;
}
static struct commit **get_bad_and_good_commits(int *rev_nr)
{
int len = 1 + good_revs.sha1_nr;
struct commit **rev = xmalloc(len * sizeof(*rev));
int i, n = 0;
rev[n++] = get_commit_reference(current_bad_sha1);
for (i = 0; i < good_revs.sha1_nr; i++)
rev[n++] = get_commit_reference(good_revs.sha1[i]);
*rev_nr = n;
return rev;
}
static void handle_bad_merge_base(void)
{
if (is_expected_rev(current_bad_sha1)) {
char *bad_hex = sha1_to_hex(current_bad_sha1);
char *good_hex = join_sha1_array_hex(&good_revs, ' ');
fprintf(stderr, "The merge base %s is bad.\n"
"This means the bug has been fixed "
"between %s and [%s].\n",
bad_hex, bad_hex, good_hex);
exit(3);
}
fprintf(stderr, "Some good revs are not ancestor of the bad rev.\n"
"git bisect cannot work properly in this case.\n"
"Maybe you mistake good and bad revs?\n");
exit(1);
}
void handle_skipped_merge_base(const unsigned char *mb)
{
char *mb_hex = sha1_to_hex(mb);
char *bad_hex = sha1_to_hex(current_bad_sha1);
char *good_hex = join_sha1_array_hex(&good_revs, ' ');
fprintf(stderr, "Warning: the merge base between %s and [%s] "
"must be skipped.\n"
"So we cannot be sure the first bad commit is "
"between %s and %s.\n"
"We continue anyway.\n",
bad_hex, good_hex, mb_hex, bad_hex);
free(good_hex);
}
/*
* "check_merge_bases" checks that merge bases are not "bad".
*
* - If one is "bad", it means the user assumed something wrong
* and we must exit with a non 0 error code.
* - If one is "good", that's good, we have nothing to do.
* - If one is "skipped", we can't know but we should warn.
* - If we don't know, we should check it out and ask the user to test.
*/
static void check_merge_bases(void)
{
struct commit_list *result;
int rev_nr;
struct commit **rev = get_bad_and_good_commits(&rev_nr);
result = get_merge_bases_many(rev[0], rev_nr - 1, rev + 1, 0);
for (; result; result = result->next) {
const unsigned char *mb = result->item->object.sha1;
if (!hashcmp(mb, current_bad_sha1)) {
handle_bad_merge_base();
} else if (0 <= lookup_sha1_array(&good_revs, mb)) {
continue;
} else if (0 <= lookup_sha1_array(&skipped_revs, mb)) {
handle_skipped_merge_base(mb);
} else {
printf("Bisecting: a merge base must be tested\n");
exit(bisect_checkout(sha1_to_hex(mb)));
}
}
free(rev);
free_commit_list(result);
}
static int check_ancestors(const char *prefix)
{
struct rev_info revs;
struct object_array pending_copy;
int i, res;
bisect_rev_setup(&revs, prefix, "^%s", "%s", 0);
/* Save pending objects, so they can be cleaned up later. */
memset(&pending_copy, 0, sizeof(pending_copy));
for (i = 0; i < revs.pending.nr; i++)
add_object_array(revs.pending.objects[i].item,
revs.pending.objects[i].name,
&pending_copy);
bisect_common(&revs);
res = (revs.commits != NULL);
/* Clean up objects used, as they will be reused. */
for (i = 0; i < pending_copy.nr; i++) {
struct object *o = pending_copy.objects[i].item;
clear_commit_marks((struct commit *)o, ALL_REV_FLAGS);
}
return res;
}
/*
* "check_good_are_ancestors_of_bad" checks that all "good" revs are
* ancestor of the "bad" rev.
*
* If that's not the case, we need to check the merge bases.
* If a merge base must be tested by the user, its source code will be
* checked out to be tested by the user and we will exit.
*/
static void check_good_are_ancestors_of_bad(const char *prefix)
{
const char *filename = git_path("BISECT_ANCESTORS_OK");
struct stat st;
int fd;
if (!current_bad_sha1)
die("a bad revision is needed");
/* Check if file BISECT_ANCESTORS_OK exists. */
if (!stat(filename, &st) && S_ISREG(st.st_mode))
return;
/* Bisecting with no good rev is ok. */
if (good_revs.sha1_nr == 0)
return;
/* Check if all good revs are ancestor of the bad rev. */
if (check_ancestors(prefix))
check_merge_bases();
/* Create file BISECT_ANCESTORS_OK. */
fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY, 0600);
if (fd < 0)
warning("could not create file '%s': %s",
filename, strerror(errno));
else
close(fd);
}
/*
* This does "git diff-tree --pretty COMMIT" without one fork+exec.
*/
static void show_diff_tree(const char *prefix, struct commit *commit)
{
struct rev_info opt;
/* diff-tree init */
init_revisions(&opt, prefix);
git_config(git_diff_basic_config, NULL); /* no "diff" UI options */
opt.abbrev = 0;
opt.diff = 1;
/* This is what "--pretty" does */
opt.verbose_header = 1;
opt.use_terminator = 0;
opt.commit_format = CMIT_FMT_DEFAULT;
/* diff-tree init */
if (!opt.diffopt.output_format)
opt.diffopt.output_format = DIFF_FORMAT_RAW;
log_tree_commit(&opt, commit);
}
/*
* We use the convention that exiting with an exit code 10 means that
* the bisection process finished successfully.
* In this case the calling shell script should exit 0.
*/
int bisect_next_all(const char *prefix)
{
struct rev_info revs;
struct commit_list *tried;
int reaches = 0, all = 0, nr;
const unsigned char *bisect_rev;
char bisect_rev_hex[41];
if (read_bisect_refs())
die("reading bisect refs failed");
check_good_are_ancestors_of_bad(prefix);
bisect_rev_setup(&revs, prefix, "%s", "^%s", 1);
revs.limited = 1;
bisect_common(&revs);
revs.commits = find_bisection(revs.commits, &reaches, &all,
!!skipped_revs.sha1_nr);
revs.commits = filter_skipped(revs.commits, &tried, 0);
if (!revs.commits) {
/*
* We should exit here only if the "bad"
* commit is also a "skip" commit.
*/
exit_if_skipped_commits(tried, NULL);
printf("%s was both good and bad\n",
sha1_to_hex(current_bad_sha1));
exit(1);
}
bisect_rev = revs.commits->item->object.sha1;
memcpy(bisect_rev_hex, sha1_to_hex(bisect_rev), 41);
if (!hashcmp(bisect_rev, current_bad_sha1)) {
exit_if_skipped_commits(tried, current_bad_sha1);
printf("%s is first bad commit\n", bisect_rev_hex);
show_diff_tree(prefix, revs.commits->item);
/* This means the bisection process succeeded. */
exit(10);
}
nr = all - reaches - 1;
printf("Bisecting: %d revisions left to test after this "
"(roughly %d steps)\n", nr, estimate_bisect_steps(all));
return bisect_checkout(bisect_rev_hex);
}
|