7 #include "list-objects.h"
9 #include "sha1-lookup.h"
10 #include "run-command.h"
13 #include "sha1-array.h"
14 #include "argv-array.h"
16 static struct oid_array good_revs
;
17 static struct oid_array skipped_revs
;
19 static struct object_id
*current_bad_oid
;
21 static const char *argv_checkout
[] = {"checkout", "-q", NULL
, "--", NULL
};
22 static const char *argv_show_branch
[] = {"show-branch", NULL
, NULL
};
24 static const char *term_bad
;
25 static const char *term_good
;
27 /* Remember to update object flag allocation in object.h */
28 #define COUNTED (1u<<16)
31 * This is a truly stupid algorithm, but it's only
32 * used for bisection, and we just don't care enough.
34 * We care just barely enough to avoid recursing for
37 static int count_distance(struct commit_list
*entry
)
42 struct commit
*commit
= entry
->item
;
43 struct commit_list
*p
;
45 if (commit
->object
.flags
& (UNINTERESTING
| COUNTED
))
47 if (!(commit
->object
.flags
& TREESAME
))
49 commit
->object
.flags
|= COUNTED
;
55 nr
+= count_distance(p
);
64 static void clear_distance(struct commit_list
*list
)
67 struct commit
*commit
= list
->item
;
68 commit
->object
.flags
&= ~COUNTED
;
73 #define DEBUG_BISECT 0
75 static inline int weight(struct commit_list
*elem
)
77 return *((int*)(elem
->item
->util
));
80 static inline void weight_set(struct commit_list
*elem
, int weight
)
82 *((int*)(elem
->item
->util
)) = weight
;
85 static int count_interesting_parents(struct commit
*commit
)
87 struct commit_list
*p
;
90 for (count
= 0, p
= commit
->parents
; p
; p
= p
->next
) {
91 if (p
->item
->object
.flags
& UNINTERESTING
)
98 static inline int halfway(struct commit_list
*p
, int nr
)
101 * Don't short-cut something we are not going to return!
103 if (p
->item
->object
.flags
& TREESAME
)
108 * 2 and 3 are halfway of 5.
109 * 3 is halfway of 6 but 2 and 4 are not.
111 switch (2 * weight(p
) - nr
) {
112 case -1: case 0: case 1:
120 #define show_list(a,b,c,d) do { ; } while (0)
122 static void show_list(const char *debug
, int counted
, int nr
,
123 struct commit_list
*list
)
125 struct commit_list
*p
;
127 fprintf(stderr
, "%s (%d/%d)\n", debug
, counted
, nr
);
129 for (p
= list
; p
; p
= p
->next
) {
130 struct commit_list
*pp
;
131 struct commit
*commit
= p
->item
;
132 unsigned flags
= commit
->object
.flags
;
133 enum object_type type
;
135 char *buf
= read_sha1_file(commit
->object
.sha1
, &type
, &size
);
136 const char *subject_start
;
139 fprintf(stderr
, "%c%c%c ",
140 (flags
& TREESAME
) ? ' ' : 'T',
141 (flags
& UNINTERESTING
) ? 'U' : ' ',
142 (flags
& COUNTED
) ? 'C' : ' ');
144 fprintf(stderr
, "%3d", weight(p
));
146 fprintf(stderr
, "---");
147 fprintf(stderr
, " %.*s", 8, sha1_to_hex(commit
->object
.sha1
));
148 for (pp
= commit
->parents
; pp
; pp
= pp
->next
)
149 fprintf(stderr
, " %.*s", 8,
150 sha1_to_hex(pp
->item
->object
.sha1
));
152 subject_len
= find_commit_subject(buf
, &subject_start
);
154 fprintf(stderr
, " %.*s", subject_len
, subject_start
);
155 fprintf(stderr
, "\n");
158 #endif /* DEBUG_BISECT */
160 static struct commit_list
*best_bisection(struct commit_list
*list
, int nr
)
162 struct commit_list
*p
, *best
;
163 int best_distance
= -1;
166 for (p
= list
; p
; p
= p
->next
) {
168 unsigned flags
= p
->item
->object
.flags
;
170 if (flags
& TREESAME
)
172 distance
= weight(p
);
173 if (nr
- distance
< distance
)
174 distance
= nr
- distance
;
175 if (distance
> best_distance
) {
177 best_distance
= distance
;
185 struct commit
*commit
;
189 static int compare_commit_dist(const void *a_
, const void *b_
)
191 struct commit_dist
*a
, *b
;
193 a
= (struct commit_dist
*)a_
;
194 b
= (struct commit_dist
*)b_
;
195 if (a
->distance
!= b
->distance
)
196 return b
->distance
- a
->distance
; /* desc sort */
197 return oidcmp(&a
->commit
->object
.oid
, &b
->commit
->object
.oid
);
200 static struct commit_list
*best_bisection_sorted(struct commit_list
*list
, int nr
)
202 struct commit_list
*p
;
203 struct commit_dist
*array
= xcalloc(nr
, sizeof(*array
));
204 struct strbuf buf
= STRBUF_INIT
;
207 for (p
= list
, cnt
= 0; p
; p
= p
->next
) {
209 unsigned flags
= p
->item
->object
.flags
;
211 if (flags
& TREESAME
)
213 distance
= weight(p
);
214 if (nr
- distance
< distance
)
215 distance
= nr
- distance
;
216 array
[cnt
].commit
= p
->item
;
217 array
[cnt
].distance
= distance
;
220 QSORT(array
, cnt
, compare_commit_dist
);
221 for (p
= list
, i
= 0; i
< cnt
; i
++) {
222 struct object
*obj
= &(array
[i
].commit
->object
);
225 strbuf_addf(&buf
, "dist=%d", array
[i
].distance
);
226 add_name_decoration(DECORATION_NONE
, buf
.buf
, obj
);
228 p
->item
= array
[i
].commit
;
232 free_commit_list(p
->next
);
234 strbuf_release(&buf
);
240 * zero or positive weight is the number of interesting commits it can
241 * reach, including itself. Especially, weight = 0 means it does not
242 * reach any tree-changing commits (e.g. just above uninteresting one
243 * but traversal is with pathspec).
245 * weight = -1 means it has one parent and its distance is yet to
248 * weight = -2 means it has more than one parent and its distance is
249 * unknown. After running count_distance() first, they will get zero
250 * or positive distance.
252 static struct commit_list
*do_find_bisection(struct commit_list
*list
,
253 int nr
, int *weights
,
257 struct commit_list
*p
;
261 for (n
= 0, p
= list
; p
; p
= p
->next
) {
262 struct commit
*commit
= p
->item
;
263 unsigned flags
= commit
->object
.flags
;
265 p
->item
->util
= &weights
[n
++];
266 switch (count_interesting_parents(commit
)) {
268 if (!(flags
& TREESAME
)) {
271 show_list("bisection 2 count one",
275 * otherwise, it is known not to reach any
276 * tree-changing commit and gets weight 0.
288 show_list("bisection 2 initialize", counted
, nr
, list
);
291 * If you have only one parent in the resulting set
292 * then you can reach one commit more than that parent
293 * can reach. So we do not have to run the expensive
294 * count_distance() for single strand of pearls.
296 * However, if you have more than one parents, you cannot
297 * just add their distance and one for yourself, since
298 * they usually reach the same ancestor and you would
299 * end up counting them twice that way.
301 * So we will first count distance of merges the usual
302 * way, and then fill the blanks using cheaper algorithm.
304 for (p
= list
; p
; p
= p
->next
) {
305 if (p
->item
->object
.flags
& UNINTERESTING
)
309 weight_set(p
, count_distance(p
));
310 clear_distance(list
);
312 /* Does it happen to be at exactly half-way? */
313 if (!find_all
&& halfway(p
, nr
))
318 show_list("bisection 2 count_distance", counted
, nr
, list
);
320 while (counted
< nr
) {
321 for (p
= list
; p
; p
= p
->next
) {
322 struct commit_list
*q
;
323 unsigned flags
= p
->item
->object
.flags
;
327 for (q
= p
->item
->parents
; q
; q
= q
->next
) {
328 if (q
->item
->object
.flags
& UNINTERESTING
)
337 * weight for p is unknown but q is known.
338 * add one for p itself if p is to be counted,
339 * otherwise inherit it from q directly.
341 if (!(flags
& TREESAME
)) {
342 weight_set(p
, weight(q
)+1);
344 show_list("bisection 2 count one",
348 weight_set(p
, weight(q
));
350 /* Does it happen to be at exactly half-way? */
351 if (!find_all
&& halfway(p
, nr
))
356 show_list("bisection 2 counted all", counted
, nr
, list
);
359 return best_bisection(list
, nr
);
361 return best_bisection_sorted(list
, nr
);
364 void find_bisection(struct commit_list
**commit_list
, int *reaches
,
365 int *all
, int find_all
)
368 struct commit_list
*list
, *p
, *best
, *next
, *last
;
371 show_list("bisection 2 entry", 0, 0, *commit_list
);
374 * Count the number of total and tree-changing items on the
375 * list, while reversing the list.
377 for (nr
= on_list
= 0, last
= NULL
, p
= *commit_list
;
380 unsigned flags
= p
->item
->object
.flags
;
383 if (flags
& UNINTERESTING
) {
389 if (!(flags
& TREESAME
))
394 show_list("bisection 2 sorted", 0, nr
, list
);
397 weights
= xcalloc(on_list
, sizeof(*weights
));
399 /* Do the real work of finding bisection commit. */
400 best
= do_find_bisection(list
, nr
, weights
, find_all
);
404 *reaches
= weight(best
);
410 static int register_ref(const char *refname
, const struct object_id
*oid
,
411 int flags
, void *cb_data
)
413 struct strbuf good_prefix
= STRBUF_INIT
;
414 strbuf_addstr(&good_prefix
, term_good
);
415 strbuf_addstr(&good_prefix
, "-");
417 if (!strcmp(refname
, term_bad
)) {
418 current_bad_oid
= xmalloc(sizeof(*current_bad_oid
));
419 oidcpy(current_bad_oid
, oid
);
420 } else if (starts_with(refname
, good_prefix
.buf
)) {
421 oid_array_append(&good_revs
, oid
);
422 } else if (starts_with(refname
, "skip-")) {
423 oid_array_append(&skipped_revs
, oid
);
426 strbuf_release(&good_prefix
);
431 static int read_bisect_refs(void)
433 return for_each_ref_in("refs/bisect/", register_ref
, NULL
);
436 static GIT_PATH_FUNC(git_path_bisect_names
, "BISECT_NAMES")
437 static GIT_PATH_FUNC(git_path_bisect_expected_rev
, "BISECT_EXPECTED_REV")
438 static GIT_PATH_FUNC(git_path_bisect_terms
, "BISECT_TERMS")
440 static void read_bisect_paths(struct argv_array
*array
)
442 struct strbuf str
= STRBUF_INIT
;
443 const char *filename
= git_path_bisect_names();
444 FILE *fp
= xfopen(filename
, "r");
446 while (strbuf_getline_lf(&str
, fp
) != EOF
) {
448 if (sq_dequote_to_argv_array(str
.buf
, array
))
449 die(_("Badly quoted content in file '%s': %s"),
453 strbuf_release(&str
);
457 static char *join_sha1_array_hex(struct oid_array
*array
, char delim
)
459 struct strbuf joined_hexs
= STRBUF_INIT
;
462 for (i
= 0; i
< array
->nr
; i
++) {
463 strbuf_addstr(&joined_hexs
, oid_to_hex(array
->oid
+ i
));
464 if (i
+ 1 < array
->nr
)
465 strbuf_addch(&joined_hexs
, delim
);
468 return strbuf_detach(&joined_hexs
, NULL
);
472 * In this function, passing a not NULL skipped_first is very special.
473 * It means that we want to know if the first commit in the list is
474 * skipped because we will want to test a commit away from it if it is
476 * So if the first commit is skipped, we cannot take the shortcut to
477 * just "return list" when we find the first non skipped commit, we
478 * have to return a fully filtered list.
480 * We use (*skipped_first == -1) to mean "it has been found that the
481 * first commit is not skipped". In this case *skipped_first is set back
482 * to 0 just before the function returns.
484 struct commit_list
*filter_skipped(struct commit_list
*list
,
485 struct commit_list
**tried
,
490 struct commit_list
*filtered
= NULL
, **f
= &filtered
;
499 if (!skipped_revs
.nr
)
503 struct commit_list
*next
= list
->next
;
505 if (0 <= oid_array_lookup(&skipped_revs
, &list
->item
->object
.oid
)) {
506 if (skipped_first
&& !*skipped_first
)
508 /* Move current to tried list */
513 if (!skipped_first
|| !*skipped_first
)
515 } else if (skipped_first
&& !*skipped_first
) {
516 /* This means we know it's not skipped */
519 /* Move current to filtered list */
528 if (skipped_first
&& *skipped_first
== -1)
534 #define PRN_MODULO 32768
537 * This is a pseudo random number generator based on "man 3 rand".
538 * It is not used properly because the seed is the argument and it
539 * is increased by one between each call, but that should not matter
540 * for this application.
542 static unsigned get_prn(unsigned count
) {
543 count
= count
* 1103515245 + 12345;
544 return (count
/65536) % PRN_MODULO
;
548 * Custom integer square root from
549 * https://en.wikipedia.org/wiki/Integer_square_root
551 static int sqrti(int val
)
559 float y
= (x
+ (float)val
/ x
) / 2;
560 d
= (y
> x
) ? y
- x
: x
- y
;
567 static struct commit_list
*skip_away(struct commit_list
*list
, int count
)
569 struct commit_list
*cur
, *previous
;
572 prn
= get_prn(count
);
573 index
= (count
* prn
/ PRN_MODULO
) * sqrti(prn
) / sqrti(PRN_MODULO
);
578 for (i
= 0; cur
; cur
= cur
->next
, i
++) {
580 if (oidcmp(&cur
->item
->object
.oid
, current_bad_oid
))
592 static struct commit_list
*managed_skipped(struct commit_list
*list
,
593 struct commit_list
**tried
)
595 int count
, skipped_first
;
599 if (!skipped_revs
.nr
)
602 list
= filter_skipped(list
, tried
, 0, &count
, &skipped_first
);
607 return skip_away(list
, count
);
610 static void bisect_rev_setup(struct rev_info
*revs
, const char *prefix
,
611 const char *bad_format
, const char *good_format
,
614 struct argv_array rev_argv
= ARGV_ARRAY_INIT
;
617 init_revisions(revs
, prefix
);
619 revs
->commit_format
= CMIT_FMT_UNSPECIFIED
;
621 /* rev_argv.argv[0] will be ignored by setup_revisions */
622 argv_array_push(&rev_argv
, "bisect_rev_setup");
623 argv_array_pushf(&rev_argv
, bad_format
, oid_to_hex(current_bad_oid
));
624 for (i
= 0; i
< good_revs
.nr
; i
++)
625 argv_array_pushf(&rev_argv
, good_format
,
626 oid_to_hex(good_revs
.oid
+ i
));
627 argv_array_push(&rev_argv
, "--");
629 read_bisect_paths(&rev_argv
);
631 setup_revisions(rev_argv
.argc
, rev_argv
.argv
, revs
, NULL
);
632 /* XXX leak rev_argv, as "revs" may still be pointing to it */
635 static void bisect_common(struct rev_info
*revs
)
637 if (prepare_revision_walk(revs
))
638 die("revision walk setup failed");
639 if (revs
->tree_objects
)
640 mark_edges_uninteresting(revs
, NULL
);
643 static void exit_if_skipped_commits(struct commit_list
*tried
,
644 const struct object_id
*bad
)
649 printf("There are only 'skip'ped commits left to test.\n"
650 "The first %s commit could be any of:\n", term_bad
);
652 for ( ; tried
; tried
= tried
->next
)
653 printf("%s\n", oid_to_hex(&tried
->item
->object
.oid
));
656 printf("%s\n", oid_to_hex(bad
));
657 printf(_("We cannot bisect more!\n"));
661 static int is_expected_rev(const struct object_id
*oid
)
663 const char *filename
= git_path_bisect_expected_rev();
665 struct strbuf str
= STRBUF_INIT
;
669 if (stat(filename
, &st
) || !S_ISREG(st
.st_mode
))
672 fp
= fopen_or_warn(filename
, "r");
676 if (strbuf_getline_lf(&str
, fp
) != EOF
)
677 res
= !strcmp(str
.buf
, oid_to_hex(oid
));
679 strbuf_release(&str
);
685 static int bisect_checkout(const struct object_id
*bisect_rev
, int no_checkout
)
687 char bisect_rev_hex
[GIT_MAX_HEXSZ
+ 1];
689 memcpy(bisect_rev_hex
, oid_to_hex(bisect_rev
), GIT_SHA1_HEXSZ
+ 1);
690 update_ref(NULL
, "BISECT_EXPECTED_REV", bisect_rev
->hash
, NULL
, 0, UPDATE_REFS_DIE_ON_ERR
);
692 argv_checkout
[2] = bisect_rev_hex
;
694 update_ref(NULL
, "BISECT_HEAD", bisect_rev
->hash
, NULL
, 0, UPDATE_REFS_DIE_ON_ERR
);
697 res
= run_command_v_opt(argv_checkout
, RUN_GIT_CMD
);
702 argv_show_branch
[1] = bisect_rev_hex
;
703 return run_command_v_opt(argv_show_branch
, RUN_GIT_CMD
);
706 static struct commit
*get_commit_reference(const struct object_id
*oid
)
708 struct commit
*r
= lookup_commit_reference(oid
);
710 die(_("Not a valid commit name %s"), oid_to_hex(oid
));
714 static struct commit
**get_bad_and_good_commits(int *rev_nr
)
719 ALLOC_ARRAY(rev
, 1 + good_revs
.nr
);
720 rev
[n
++] = get_commit_reference(current_bad_oid
);
721 for (i
= 0; i
< good_revs
.nr
; i
++)
722 rev
[n
++] = get_commit_reference(good_revs
.oid
+ i
);
728 static void handle_bad_merge_base(void)
730 if (is_expected_rev(current_bad_oid
)) {
731 char *bad_hex
= oid_to_hex(current_bad_oid
);
732 char *good_hex
= join_sha1_array_hex(&good_revs
, ' ');
733 if (!strcmp(term_bad
, "bad") && !strcmp(term_good
, "good")) {
734 fprintf(stderr
, _("The merge base %s is bad.\n"
735 "This means the bug has been fixed "
736 "between %s and [%s].\n"),
737 bad_hex
, bad_hex
, good_hex
);
738 } else if (!strcmp(term_bad
, "new") && !strcmp(term_good
, "old")) {
739 fprintf(stderr
, _("The merge base %s is new.\n"
740 "The property has changed "
741 "between %s and [%s].\n"),
742 bad_hex
, bad_hex
, good_hex
);
744 fprintf(stderr
, _("The merge base %s is %s.\n"
745 "This means the first '%s' commit is "
746 "between %s and [%s].\n"),
747 bad_hex
, term_bad
, term_good
, bad_hex
, good_hex
);
752 fprintf(stderr
, _("Some %s revs are not ancestors of the %s rev.\n"
753 "git bisect cannot work properly in this case.\n"
754 "Maybe you mistook %s and %s revs?\n"),
755 term_good
, term_bad
, term_good
, term_bad
);
759 static void handle_skipped_merge_base(const struct object_id
*mb
)
761 char *mb_hex
= oid_to_hex(mb
);
762 char *bad_hex
= oid_to_hex(current_bad_oid
);
763 char *good_hex
= join_sha1_array_hex(&good_revs
, ' ');
765 warning(_("the merge base between %s and [%s] "
767 "So we cannot be sure the first %s commit is "
768 "between %s and %s.\n"
769 "We continue anyway."),
770 bad_hex
, good_hex
, term_bad
, mb_hex
, bad_hex
);
775 * "check_merge_bases" checks that merge bases are not "bad" (or "new").
777 * - If one is "bad" (or "new"), it means the user assumed something wrong
778 * and we must exit with a non 0 error code.
779 * - If one is "good" (or "old"), that's good, we have nothing to do.
780 * - If one is "skipped", we can't know but we should warn.
781 * - If we don't know, we should check it out and ask the user to test.
783 static void check_merge_bases(int no_checkout
)
785 struct commit_list
*result
;
787 struct commit
**rev
= get_bad_and_good_commits(&rev_nr
);
789 result
= get_merge_bases_many(rev
[0], rev_nr
- 1, rev
+ 1);
791 for (; result
; result
= result
->next
) {
792 const struct object_id
*mb
= &result
->item
->object
.oid
;
793 if (!oidcmp(mb
, current_bad_oid
)) {
794 handle_bad_merge_base();
795 } else if (0 <= oid_array_lookup(&good_revs
, mb
)) {
797 } else if (0 <= oid_array_lookup(&skipped_revs
, mb
)) {
798 handle_skipped_merge_base(mb
);
800 printf(_("Bisecting: a merge base must be tested\n"));
801 exit(bisect_checkout(mb
, no_checkout
));
806 free_commit_list(result
);
809 static int check_ancestors(const char *prefix
)
811 struct rev_info revs
;
812 struct object_array pending_copy
;
815 bisect_rev_setup(&revs
, prefix
, "^%s", "%s", 0);
817 /* Save pending objects, so they can be cleaned up later. */
818 pending_copy
= revs
.pending
;
819 revs
.leak_pending
= 1;
822 * bisect_common calls prepare_revision_walk right away, which
823 * (together with .leak_pending = 1) makes us the sole owner of
824 * the list of pending objects.
826 bisect_common(&revs
);
827 res
= (revs
.commits
!= NULL
);
829 /* Clean up objects used, as they will be reused. */
830 clear_commit_marks_for_object_array(&pending_copy
, ALL_REV_FLAGS
);
832 object_array_clear(&pending_copy
);
838 * "check_good_are_ancestors_of_bad" checks that all "good" revs are
839 * ancestor of the "bad" rev.
841 * If that's not the case, we need to check the merge bases.
842 * If a merge base must be tested by the user, its source code will be
843 * checked out to be tested by the user and we will exit.
845 static void check_good_are_ancestors_of_bad(const char *prefix
, int no_checkout
)
847 char *filename
= git_pathdup("BISECT_ANCESTORS_OK");
851 if (!current_bad_oid
)
852 die(_("a %s revision is needed"), term_bad
);
854 /* Check if file BISECT_ANCESTORS_OK exists. */
855 if (!stat(filename
, &st
) && S_ISREG(st
.st_mode
))
858 /* Bisecting with no good rev is ok. */
859 if (good_revs
.nr
== 0)
862 /* Check if all good revs are ancestor of the bad rev. */
863 if (check_ancestors(prefix
))
864 check_merge_bases(no_checkout
);
866 /* Create file BISECT_ANCESTORS_OK. */
867 fd
= open(filename
, O_CREAT
| O_TRUNC
| O_WRONLY
, 0600);
869 warning_errno(_("could not create file '%s'"),
878 * This does "git diff-tree --pretty COMMIT" without one fork+exec.
880 static void show_diff_tree(const char *prefix
, struct commit
*commit
)
885 init_revisions(&opt
, prefix
);
886 git_config(git_diff_basic_config
, NULL
); /* no "diff" UI options */
890 /* This is what "--pretty" does */
891 opt
.verbose_header
= 1;
892 opt
.use_terminator
= 0;
893 opt
.commit_format
= CMIT_FMT_DEFAULT
;
896 if (!opt
.diffopt
.output_format
)
897 opt
.diffopt
.output_format
= DIFF_FORMAT_RAW
;
899 setup_revisions(0, NULL
, &opt
, NULL
);
900 log_tree_commit(&opt
, commit
);
904 * The terms used for this bisect session are stored in BISECT_TERMS.
905 * We read them and store them to adapt the messages accordingly.
906 * Default is bad/good.
908 void read_bisect_terms(const char **read_bad
, const char **read_good
)
910 struct strbuf str
= STRBUF_INIT
;
911 const char *filename
= git_path_bisect_terms();
912 FILE *fp
= fopen(filename
, "r");
915 if (errno
== ENOENT
) {
920 die_errno(_("could not read file '%s'"), filename
);
923 strbuf_getline_lf(&str
, fp
);
924 *read_bad
= strbuf_detach(&str
, NULL
);
925 strbuf_getline_lf(&str
, fp
);
926 *read_good
= strbuf_detach(&str
, NULL
);
928 strbuf_release(&str
);
933 * We use the convention that exiting with an exit code 10 means that
934 * the bisection process finished successfully.
935 * In this case the calling shell script should exit 0.
937 * If no_checkout is non-zero, the bisection process does not
938 * checkout the trial commit but instead simply updates BISECT_HEAD.
940 int bisect_next_all(const char *prefix
, int no_checkout
)
942 struct rev_info revs
;
943 struct commit_list
*tried
;
944 int reaches
= 0, all
= 0, nr
, steps
;
945 struct object_id
*bisect_rev
;
948 read_bisect_terms(&term_bad
, &term_good
);
949 if (read_bisect_refs())
950 die(_("reading bisect refs failed"));
952 check_good_are_ancestors_of_bad(prefix
, no_checkout
);
954 bisect_rev_setup(&revs
, prefix
, "%s", "^%s", 1);
957 bisect_common(&revs
);
959 find_bisection(&revs
.commits
, &reaches
, &all
, !!skipped_revs
.nr
);
960 revs
.commits
= managed_skipped(revs
.commits
, &tried
);
964 * We should exit here only if the "bad"
965 * commit is also a "skip" commit.
967 exit_if_skipped_commits(tried
, NULL
);
969 printf(_("%s was both %s and %s\n"),
970 oid_to_hex(current_bad_oid
),
977 fprintf(stderr
, _("No testable commit found.\n"
978 "Maybe you started with bad path parameters?\n"));
982 bisect_rev
= &revs
.commits
->item
->object
.oid
;
984 if (!oidcmp(bisect_rev
, current_bad_oid
)) {
985 exit_if_skipped_commits(tried
, current_bad_oid
);
986 printf("%s is the first %s commit\n", oid_to_hex(bisect_rev
),
988 show_diff_tree(prefix
, revs
.commits
->item
);
989 /* This means the bisection process succeeded. */
993 nr
= all
- reaches
- 1;
994 steps
= estimate_bisect_steps(all
);
996 steps_msg
= xstrfmt(Q_("(roughly %d step)", "(roughly %d steps)",
999 * TRANSLATORS: the last %s will be replaced with "(roughly %d
1000 * steps)" translation.
1002 printf(Q_("Bisecting: %d revision left to test after this %s\n",
1003 "Bisecting: %d revisions left to test after this %s\n",
1004 nr
), nr
, steps_msg
);
1007 return bisect_checkout(bisect_rev
, no_checkout
);
1010 static inline int log2i(int n
)
1014 for (; n
> 1; n
>>= 1)
1020 static inline int exp2i(int n
)
1026 * Estimate the number of bisect steps left (after the current step)
1028 * For any x between 0 included and 2^n excluded, the probability for
1029 * n - 1 steps left looks like:
1031 * P(2^n + x) == (2^n - x) / (2^n + x)
1033 * and P(2^n + x) < 0.5 means 2^n < 3x
1035 int estimate_bisect_steps(int all
)
1046 return (e
< 3 * x
) ? n
: n
- 1;