summaryrefslogtreecommitdiff
path: root/builtin/bisect.c
blob: 4b2143d4557a8de9007b4885866c1d4ca9668cc8 (plain)
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
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
#include "builtin.h"
#include "cache.h"
#include "environment.h"
#include "gettext.h"
#include "hex.h"
#include "object-name.h"
#include "parse-options.h"
#include "bisect.h"
#include "refs.h"
#include "dir.h"
#include "strvec.h"
#include "run-command.h"
#include "oid-array.h"
#include "prompt.h"
#include "quote.h"
#include "revision.h"
#include "wrapper.h"

static GIT_PATH_FUNC(git_path_bisect_terms, "BISECT_TERMS")
static GIT_PATH_FUNC(git_path_bisect_expected_rev, "BISECT_EXPECTED_REV")
static GIT_PATH_FUNC(git_path_bisect_ancestors_ok, "BISECT_ANCESTORS_OK")
static GIT_PATH_FUNC(git_path_bisect_start, "BISECT_START")
static GIT_PATH_FUNC(git_path_bisect_log, "BISECT_LOG")
static GIT_PATH_FUNC(git_path_bisect_names, "BISECT_NAMES")
static GIT_PATH_FUNC(git_path_bisect_first_parent, "BISECT_FIRST_PARENT")
static GIT_PATH_FUNC(git_path_bisect_run, "BISECT_RUN")

#define BUILTIN_GIT_BISECT_START_USAGE \
	N_("git bisect start [--term-{new,bad}=<term> --term-{old,good}=<term>]" \
	   "    [--no-checkout] [--first-parent] [<bad> [<good>...]] [--]" \
	   "    [<pathspec>...]")
#define BUILTIN_GIT_BISECT_STATE_USAGE \
	N_("git bisect (good|bad) [<rev>...]")
#define BUILTIN_GIT_BISECT_TERMS_USAGE \
	"git bisect terms [--term-good | --term-bad]"
#define BUILTIN_GIT_BISECT_SKIP_USAGE \
	N_("git bisect skip [(<rev>|<range>)...]")
#define BUILTIN_GIT_BISECT_NEXT_USAGE \
	"git bisect next"
#define BUILTIN_GIT_BISECT_RESET_USAGE \
	N_("git bisect reset [<commit>]")
#define BUILTIN_GIT_BISECT_VISUALIZE_USAGE \
	"git bisect visualize"
#define BUILTIN_GIT_BISECT_REPLAY_USAGE \
	N_("git bisect replay <logfile>")
#define BUILTIN_GIT_BISECT_LOG_USAGE \
	"git bisect log"
#define BUILTIN_GIT_BISECT_RUN_USAGE \
	N_("git bisect run <cmd>...")

static const char * const git_bisect_usage[] = {
	BUILTIN_GIT_BISECT_START_USAGE,
	BUILTIN_GIT_BISECT_STATE_USAGE,
	BUILTIN_GIT_BISECT_TERMS_USAGE,
	BUILTIN_GIT_BISECT_SKIP_USAGE,
	BUILTIN_GIT_BISECT_NEXT_USAGE,
	BUILTIN_GIT_BISECT_RESET_USAGE,
	BUILTIN_GIT_BISECT_VISUALIZE_USAGE,
	BUILTIN_GIT_BISECT_REPLAY_USAGE,
	BUILTIN_GIT_BISECT_LOG_USAGE,
	BUILTIN_GIT_BISECT_RUN_USAGE,
	NULL
};

struct add_bisect_ref_data {
	struct rev_info *revs;
	unsigned int object_flags;
};

struct bisect_terms {
	char *term_good;
	char *term_bad;
};

static void free_terms(struct bisect_terms *terms)
{
	FREE_AND_NULL(terms->term_good);
	FREE_AND_NULL(terms->term_bad);
}

static void set_terms(struct bisect_terms *terms, const char *bad,
		      const char *good)
{
	free((void *)terms->term_good);
	terms->term_good = xstrdup(good);
	free((void *)terms->term_bad);
	terms->term_bad = xstrdup(bad);
}

static const char vocab_bad[] = "bad|new";
static const char vocab_good[] = "good|old";

static int bisect_autostart(struct bisect_terms *terms);

/*
 * Check whether the string `term` belongs to the set of strings
 * included in the variable arguments.
 */
LAST_ARG_MUST_BE_NULL
static int one_of(const char *term, ...)
{
	int res = 0;
	va_list matches;
	const char *match;

	va_start(matches, term);
	while (!res && (match = va_arg(matches, const char *)))
		res = !strcmp(term, match);
	va_end(matches);

	return res;
}

/*
 * return code BISECT_INTERNAL_SUCCESS_MERGE_BASE
 * and BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND are codes
 * that indicate special success.
 */

static int is_bisect_success(enum bisect_error res)
{
	return !res ||
		res == BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND ||
		res == BISECT_INTERNAL_SUCCESS_MERGE_BASE;
}

static int write_in_file(const char *path, const char *mode, const char *format, va_list args)
{
	FILE *fp = NULL;
	int res = 0;

	if (strcmp(mode, "w") && strcmp(mode, "a"))
		BUG("write-in-file does not support '%s' mode", mode);
	fp = fopen(path, mode);
	if (!fp)
		return error_errno(_("cannot open file '%s' in mode '%s'"), path, mode);
	res = vfprintf(fp, format, args);

	if (res < 0) {
		int saved_errno = errno;
		fclose(fp);
		errno = saved_errno;
		return error_errno(_("could not write to file '%s'"), path);
	}

	return fclose(fp);
}

__attribute__((format (printf, 2, 3)))
static int write_to_file(const char *path, const char *format, ...)
{
	int res;
	va_list args;

	va_start(args, format);
	res = write_in_file(path, "w", format, args);
	va_end(args);

	return res;
}

__attribute__((format (printf, 2, 3)))
static int append_to_file(const char *path, const char *format, ...)
{
	int res;
	va_list args;

	va_start(args, format);
	res = write_in_file(path, "a", format, args);
	va_end(args);

	return res;
}

static int print_file_to_stdout(const char *path)
{
	int fd = open(path, O_RDONLY);
	int ret = 0;

	if (fd < 0)
		return error_errno(_("cannot open file '%s' for reading"), path);
	if (copy_fd(fd, 1) < 0)
		ret = error_errno(_("failed to read '%s'"), path);
	close(fd);
	return ret;
}

static int check_term_format(const char *term, const char *orig_term)
{
	int res;
	char *new_term = xstrfmt("refs/bisect/%s", term);

	res = check_refname_format(new_term, 0);
	free(new_term);

	if (res)
		return error(_("'%s' is not a valid term"), term);

	if (one_of(term, "help", "start", "skip", "next", "reset",
			"visualize", "view", "replay", "log", "run", "terms", NULL))
		return error(_("can't use the builtin command '%s' as a term"), term);

	/*
	 * In theory, nothing prevents swapping completely good and bad,
	 * but this situation could be confusing and hasn't been tested
	 * enough. Forbid it for now.
	 */

	if ((strcmp(orig_term, "bad") && one_of(term, "bad", "new", NULL)) ||
		 (strcmp(orig_term, "good") && one_of(term, "good", "old", NULL)))
		return error(_("can't change the meaning of the term '%s'"), term);

	return 0;
}

static int write_terms(const char *bad, const char *good)
{
	int res;

	if (!strcmp(bad, good))
		return error(_("please use two different terms"));

	if (check_term_format(bad, "bad") || check_term_format(good, "good"))
		return -1;

	res = write_to_file(git_path_bisect_terms(), "%s\n%s\n", bad, good);

	return res;
}

static int bisect_reset(const char *commit)
{
	struct strbuf branch = STRBUF_INIT;

	if (!commit) {
		if (strbuf_read_file(&branch, git_path_bisect_start(), 0) < 1) {
			printf(_("We are not bisecting.\n"));
			return 0;
		}
		strbuf_rtrim(&branch);
	} else {
		struct object_id oid;

		if (repo_get_oid_commit(the_repository, commit, &oid))
			return error(_("'%s' is not a valid commit"), commit);
		strbuf_addstr(&branch, commit);
	}

	if (!ref_exists("BISECT_HEAD")) {
		struct child_process cmd = CHILD_PROCESS_INIT;

		cmd.git_cmd = 1;
		strvec_pushl(&cmd.args, "checkout", "--ignore-other-worktrees",
				branch.buf, "--", NULL);
		if (run_command(&cmd)) {
			error(_("could not check out original"
				" HEAD '%s'. Try 'git bisect"
				" reset <commit>'."), branch.buf);
			strbuf_release(&branch);
			return -1;
		}
	}

	strbuf_release(&branch);
	return bisect_clean_state();
}

static void log_commit(FILE *fp, char *fmt, const char *state,
		       struct commit *commit)
{
	struct pretty_print_context pp = {0};
	struct strbuf commit_msg = STRBUF_INIT;
	char *label = xstrfmt(fmt, state);

	repo_format_commit_message(the_repository, commit, "%s", &commit_msg,
				   &pp);

	fprintf(fp, "# %s: [%s] %s\n", label, oid_to_hex(&commit->object.oid),
		commit_msg.buf);

	strbuf_release(&commit_msg);
	free(label);
}

static int bisect_write(const char *state, const char *rev,
			const struct bisect_terms *terms, int nolog)
{
	struct strbuf tag = STRBUF_INIT;
	struct object_id oid;
	struct commit *commit;
	FILE *fp = NULL;
	int res = 0;

	if (!strcmp(state, terms->term_bad)) {
		strbuf_addf(&tag, "refs/bisect/%s", state);
	} else if (one_of(state, terms->term_good, "skip", NULL)) {
		strbuf_addf(&tag, "refs/bisect/%s-%s", state, rev);
	} else {
		res = error(_("Bad bisect_write argument: %s"), state);
		goto finish;
	}

	if (repo_get_oid(the_repository, rev, &oid)) {
		res = error(_("couldn't get the oid of the rev '%s'"), rev);
		goto finish;
	}

	if (update_ref(NULL, tag.buf, &oid, NULL, 0,
		       UPDATE_REFS_MSG_ON_ERR)) {
		res = -1;
		goto finish;
	}

	fp = fopen(git_path_bisect_log(), "a");
	if (!fp) {
		res = error_errno(_("couldn't open the file '%s'"), git_path_bisect_log());
		goto finish;
	}

	commit = lookup_commit_reference(the_repository, &oid);
	log_commit(fp, "%s", state, commit);

	if (!nolog)
		fprintf(fp, "git bisect %s %s\n", state, rev);

finish:
	if (fp)
		fclose(fp);
	strbuf_release(&tag);
	return res;
}

static int check_and_set_terms(struct bisect_terms *terms, const char *cmd)
{
	int has_term_file = !is_empty_or_missing_file(git_path_bisect_terms());

	if (one_of(cmd, "skip", "start", "terms", NULL))
		return 0;

	if (has_term_file && strcmp(cmd, terms->term_bad) &&
	    strcmp(cmd, terms->term_good))
		return error(_("Invalid command: you're currently in a "
				"%s/%s bisect"), terms->term_bad,
				terms->term_good);

	if (!has_term_file) {
		if (one_of(cmd, "bad", "good", NULL)) {
			set_terms(terms, "bad", "good");
			return write_terms(terms->term_bad, terms->term_good);
		}
		if (one_of(cmd, "new", "old", NULL)) {
			set_terms(terms, "new", "old");
			return write_terms(terms->term_bad, terms->term_good);
		}
	}

	return 0;
}

static int inc_nr(const char *refname UNUSED,
		  const struct object_id *oid UNUSED,
		  int flag UNUSED, void *cb_data)
{
	unsigned int *nr = (unsigned int *)cb_data;
	(*nr)++;
	return 0;
}

static const char need_bad_and_good_revision_warning[] =
	N_("You need to give me at least one %s and %s revision.\n"
	   "You can use \"git bisect %s\" and \"git bisect %s\" for that.");

static const char need_bisect_start_warning[] =
	N_("You need to start by \"git bisect start\".\n"
	   "You then need to give me at least one %s and %s revision.\n"
	   "You can use \"git bisect %s\" and \"git bisect %s\" for that.");

static int decide_next(const struct bisect_terms *terms,
		       const char *current_term, int missing_good,
		       int missing_bad)
{
	if (!missing_good && !missing_bad)
		return 0;
	if (!current_term)
		return -1;

	if (missing_good && !missing_bad &&
	    !strcmp(current_term, terms->term_good)) {
		char *yesno;
		/*
		 * have bad (or new) but not good (or old). We could bisect
		 * although this is less optimum.
		 */
		warning(_("bisecting only with a %s commit"), terms->term_bad);
		if (!isatty(0))
			return 0;
		/*
		 * TRANSLATORS: Make sure to include [Y] and [n] in your
		 * translation. The program will only accept English input
		 * at this point.
		 */
		yesno = git_prompt(_("Are you sure [Y/n]? "), PROMPT_ECHO);
		if (starts_with(yesno, "N") || starts_with(yesno, "n"))
			return -1;
		return 0;
	}

	if (!is_empty_or_missing_file(git_path_bisect_start()))
		return error(_(need_bad_and_good_revision_warning),
			     vocab_bad, vocab_good, vocab_bad, vocab_good);
	else
		return error(_(need_bisect_start_warning),
			     vocab_good, vocab_bad, vocab_good, vocab_bad);
}

static void bisect_status(struct bisect_state *state,
			  const struct bisect_terms *terms)
{
	char *bad_ref = xstrfmt("refs/bisect/%s", terms->term_bad);
	char *good_glob = xstrfmt("%s-*", terms->term_good);

	if (ref_exists(bad_ref))
		state->nr_bad = 1;

	for_each_glob_ref_in(inc_nr, good_glob, "refs/bisect/",
			     (void *) &state->nr_good);

	free(good_glob);
	free(bad_ref);
}

__attribute__((format (printf, 1, 2)))
static void bisect_log_printf(const char *fmt, ...)
{
	struct strbuf buf = STRBUF_INIT;
	va_list ap;

	va_start(ap, fmt);
	strbuf_vaddf(&buf, fmt, ap);
	va_end(ap);

	printf("%s", buf.buf);
	append_to_file(git_path_bisect_log(), "# %s", buf.buf);

	strbuf_release(&buf);
}

static void bisect_print_status(const struct bisect_terms *terms)
{
	struct bisect_state state = { 0 };

	bisect_status(&state, terms);

	/* If we had both, we'd already be started, and shouldn't get here. */
	if (state.nr_good && state.nr_bad)
		return;

	if (!state.nr_good && !state.nr_bad)
		bisect_log_printf(_("status: waiting for both good and bad commits\n"));
	else if (state.nr_good)
		bisect_log_printf(Q_("status: waiting for bad commit, %d good commit known\n",
				     "status: waiting for bad commit, %d good commits known\n",
				     state.nr_good), state.nr_good);
	else
		bisect_log_printf(_("status: waiting for good commit(s), bad commit known\n"));
}

static int bisect_next_check(const struct bisect_terms *terms,
			     const char *current_term)
{
	struct bisect_state state = { 0 };
	bisect_status(&state, terms);
	return decide_next(terms, current_term, !state.nr_good, !state.nr_bad);
}

static int get_terms(struct bisect_terms *terms)
{
	struct strbuf str = STRBUF_INIT;
	FILE *fp = NULL;
	int res = 0;

	fp = fopen(git_path_bisect_terms(), "r");
	if (!fp) {
		res = -1;
		goto finish;
	}

	free_terms(terms);
	strbuf_getline_lf(&str, fp);
	terms->term_bad = strbuf_detach(&str, NULL);
	strbuf_getline_lf(&str, fp);
	terms->term_good = strbuf_detach(&str, NULL);

finish:
	if (fp)
		fclose(fp);
	strbuf_release(&str);
	return res;
}

static int bisect_terms(struct bisect_terms *terms, const char *option)
{
	if (get_terms(terms))
		return error(_("no terms defined"));

	if (!option) {
		printf(_("Your current terms are %s for the old state\n"
			 "and %s for the new state.\n"),
		       terms->term_good, terms->term_bad);
		return 0;
	}
	if (one_of(option, "--term-good", "--term-old", NULL))
		printf("%s\n", terms->term_good);
	else if (one_of(option, "--term-bad", "--term-new", NULL))
		printf("%s\n", terms->term_bad);
	else
		return error(_("invalid argument %s for 'git bisect terms'.\n"
			       "Supported options are: "
			       "--term-good|--term-old and "
			       "--term-bad|--term-new."), option);

	return 0;
}

static int bisect_append_log_quoted(const char **argv)
{
	int res = 0;
	FILE *fp = fopen(git_path_bisect_log(), "a");
	struct strbuf orig_args = STRBUF_INIT;

	if (!fp)
		return -1;

	if (fprintf(fp, "git bisect start") < 1) {
		res = -1;
		goto finish;
	}

	sq_quote_argv(&orig_args, argv);
	if (fprintf(fp, "%s\n", orig_args.buf) < 1)
		res = -1;

finish:
	fclose(fp);
	strbuf_release(&orig_args);
	return res;
}

static int add_bisect_ref(const char *refname, const struct object_id *oid,
			  int flags UNUSED, void *cb)
{
	struct add_bisect_ref_data *data = cb;

	add_pending_oid(data->revs, refname, oid, data->object_flags);

	return 0;
}

static int prepare_revs(struct bisect_terms *terms, struct rev_info *revs)
{
	int res = 0;
	struct add_bisect_ref_data cb = { revs };
	char *good = xstrfmt("%s-*", terms->term_good);

	/*
	 * We cannot use terms->term_bad directly in
	 * for_each_glob_ref_in() and we have to append a '*' to it,
	 * otherwise for_each_glob_ref_in() will append '/' and '*'.
	 */
	char *bad = xstrfmt("%s*", terms->term_bad);

	/*
	 * It is important to reset the flags used by revision walks
	 * as the previous call to bisect_next_all() in turn
	 * sets up a revision walk.
	 */
	reset_revision_walk();
	repo_init_revisions(the_repository, revs, NULL);
	setup_revisions(0, NULL, revs, NULL);
	for_each_glob_ref_in(add_bisect_ref, bad, "refs/bisect/", &cb);
	cb.object_flags = UNINTERESTING;
	for_each_glob_ref_in(add_bisect_ref, good, "refs/bisect/", &cb);
	if (prepare_revision_walk(revs))
		res = error(_("revision walk setup failed\n"));

	free(good);
	free(bad);
	return res;
}

static int bisect_skipped_commits(struct bisect_terms *terms)
{
	int res;
	FILE *fp = NULL;
	struct rev_info revs;
	struct commit *commit;
	struct pretty_print_context pp = {0};
	struct strbuf commit_name = STRBUF_INIT;

	res = prepare_revs(terms, &revs);
	if (res)
		return res;

	fp = fopen(git_path_bisect_log(), "a");
	if (!fp)
		return error_errno(_("could not open '%s' for appending"),
				  git_path_bisect_log());

	if (fprintf(fp, "# only skipped commits left to test\n") < 0)
		return error_errno(_("failed to write to '%s'"), git_path_bisect_log());

	while ((commit = get_revision(&revs)) != NULL) {
		strbuf_reset(&commit_name);
		repo_format_commit_message(the_repository, commit, "%s",
					   &commit_name, &pp);
		fprintf(fp, "# possible first %s commit: [%s] %s\n",
			terms->term_bad, oid_to_hex(&commit->object.oid),
			commit_name.buf);
	}

	/*
	 * Reset the flags used by revision walks in case
	 * there is another revision walk after this one.
	 */
	reset_revision_walk();

	strbuf_release(&commit_name);
	release_revisions(&revs);
	fclose(fp);
	return 0;
}

static int bisect_successful(struct bisect_terms *terms)
{
	struct object_id oid;
	struct commit *commit;
	struct pretty_print_context pp = {0};
	struct strbuf commit_name = STRBUF_INIT;
	char *bad_ref = xstrfmt("refs/bisect/%s",terms->term_bad);
	int res;

	read_ref(bad_ref, &oid);
	commit = lookup_commit_reference_by_name(bad_ref);
	repo_format_commit_message(the_repository, commit, "%s", &commit_name,
				   &pp);

	res = append_to_file(git_path_bisect_log(), "# first %s commit: [%s] %s\n",
			    terms->term_bad, oid_to_hex(&commit->object.oid),
			    commit_name.buf);

	strbuf_release(&commit_name);
	free(bad_ref);
	return res;
}

static enum bisect_error bisect_next(struct bisect_terms *terms, const char *prefix)
{
	enum bisect_error res;

	if (bisect_autostart(terms))
		return BISECT_FAILED;

	if (bisect_next_check(terms, terms->term_good))
		return BISECT_FAILED;

	/* Perform all bisection computation */
	res = bisect_next_all(the_repository, prefix);

	if (res == BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND) {
		res = bisect_successful(terms);
		return res ? res : BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND;
	} else if (res == BISECT_ONLY_SKIPPED_LEFT) {
		res = bisect_skipped_commits(terms);
		return res ? res : BISECT_ONLY_SKIPPED_LEFT;
	}
	return res;
}

static enum bisect_error bisect_auto_next(struct bisect_terms *terms, const char *prefix)
{
	if (bisect_next_check(terms, NULL)) {
		bisect_print_status(terms);
		return BISECT_OK;
	}

	return bisect_next(terms, prefix);
}

static enum bisect_error bisect_start(struct bisect_terms *terms, int argc,
				      const char **argv)
{
	int no_checkout = 0;
	int first_parent_only = 0;
	int i, has_double_dash = 0, must_write_terms = 0, bad_seen = 0;
	int flags, pathspec_pos;
	enum bisect_error res = BISECT_OK;
	struct string_list revs = STRING_LIST_INIT_DUP;
	struct string_list states = STRING_LIST_INIT_DUP;
	struct strbuf start_head = STRBUF_INIT;
	struct strbuf bisect_names = STRBUF_INIT;
	struct object_id head_oid;
	struct object_id oid;
	const char *head;

	if (is_bare_repository())
		no_checkout = 1;

	/*
	 * Check for one bad and then some good revisions
	 */
	for (i = 0; i < argc; i++) {
		if (!strcmp(argv[i], "--")) {
			has_double_dash = 1;
			break;
		}
	}

	for (i = 0; i < argc; i++) {
		const char *arg = argv[i];
		if (!strcmp(argv[i], "--")) {
			break;
		} else if (!strcmp(arg, "--no-checkout")) {
			no_checkout = 1;
		} else if (!strcmp(arg, "--first-parent")) {
			first_parent_only = 1;
		} else if (!strcmp(arg, "--term-good") ||
			 !strcmp(arg, "--term-old")) {
			i++;
			if (argc <= i)
				return error(_("'' is not a valid term"));
			must_write_terms = 1;
			free((void *) terms->term_good);
			terms->term_good = xstrdup(argv[i]);
		} else if (skip_prefix(arg, "--term-good=", &arg) ||
			   skip_prefix(arg, "--term-old=", &arg)) {
			must_write_terms = 1;
			free((void *) terms->term_good);
			terms->term_good = xstrdup(arg);
		} else if (!strcmp(arg, "--term-bad") ||
			 !strcmp(arg, "--term-new")) {
			i++;
			if (argc <= i)
				return error(_("'' is not a valid term"));
			must_write_terms = 1;
			free((void *) terms->term_bad);
			terms->term_bad = xstrdup(argv[i]);
		} else if (skip_prefix(arg, "--term-bad=", &arg) ||
			   skip_prefix(arg, "--term-new=", &arg)) {
			must_write_terms = 1;
			free((void *) terms->term_bad);
			terms->term_bad = xstrdup(arg);
		} else if (starts_with(arg, "--")) {
			return error(_("unrecognized option: '%s'"), arg);
		} else if (!get_oidf(&oid, "%s^{commit}", arg)) {
			string_list_append(&revs, oid_to_hex(&oid));
		} else if (has_double_dash) {
			die(_("'%s' does not appear to be a valid "
			      "revision"), arg);
		} else {
			break;
		}
	}
	pathspec_pos = i;

	/*
	 * The user ran "git bisect start <sha1> <sha1>", hence did not
	 * explicitly specify the terms, but we are already starting to
	 * set references named with the default terms, and won't be able
	 * to change afterwards.
	 */
	if (revs.nr)
		must_write_terms = 1;
	for (i = 0; i < revs.nr; i++) {
		if (bad_seen) {
			string_list_append(&states, terms->term_good);
		} else {
			bad_seen = 1;
			string_list_append(&states, terms->term_bad);
		}
	}

	/*
	 * Verify HEAD
	 */
	head = resolve_ref_unsafe("HEAD", 0, &head_oid, &flags);
	if (!head)
		if (repo_get_oid(the_repository, "HEAD", &head_oid))
			return error(_("bad HEAD - I need a HEAD"));

	/*
	 * Check if we are bisecting
	 */
	if (!is_empty_or_missing_file(git_path_bisect_start())) {
		/* Reset to the rev from where we started */
		strbuf_read_file(&start_head, git_path_bisect_start(), 0);
		strbuf_trim(&start_head);
		if (!no_checkout) {
			struct child_process cmd = CHILD_PROCESS_INIT;

			cmd.git_cmd = 1;
			strvec_pushl(&cmd.args, "checkout", start_head.buf,
				     "--", NULL);
			if (run_command(&cmd)) {
				res = error(_("checking out '%s' failed."
						 " Try 'git bisect start "
						 "<valid-branch>'."),
					       start_head.buf);
				goto finish;
			}
		}
	} else {
		/* Get the rev from where we start. */
		if (!repo_get_oid(the_repository, head, &head_oid) &&
		    !starts_with(head, "refs/heads/")) {
			strbuf_reset(&start_head);
			strbuf_addstr(&start_head, oid_to_hex(&head_oid));
		} else if (!repo_get_oid(the_repository, head, &head_oid) &&
			   skip_prefix(head, "refs/heads/", &head)) {
			strbuf_addstr(&start_head, head);
		} else {
			return error(_("bad HEAD - strange symbolic ref"));
		}
	}

	/*
	 * Get rid of any old bisect state.
	 */
	if (bisect_clean_state())
		return BISECT_FAILED;

	/*
	 * Write new start state
	 */
	write_file(git_path_bisect_start(), "%s\n", start_head.buf);

	if (first_parent_only)
		write_file(git_path_bisect_first_parent(), "\n");

	if (no_checkout) {
		if (repo_get_oid(the_repository, start_head.buf, &oid) < 0) {
			res = error(_("invalid ref: '%s'"), start_head.buf);
			goto finish;
		}
		if (update_ref(NULL, "BISECT_HEAD", &oid, NULL, 0,
			       UPDATE_REFS_MSG_ON_ERR)) {
			res = BISECT_FAILED;
			goto finish;
		}
	}

	if (pathspec_pos < argc - 1)
		sq_quote_argv(&bisect_names, argv + pathspec_pos);
	write_file(git_path_bisect_names(), "%s\n", bisect_names.buf);

	for (i = 0; i < states.nr; i++)
		if (bisect_write(states.items[i].string,
				 revs.items[i].string, terms, 1)) {
			res = BISECT_FAILED;
			goto finish;
		}

	if (must_write_terms && write_terms(terms->term_bad,
					    terms->term_good)) {
		res = BISECT_FAILED;
		goto finish;
	}

	res = bisect_append_log_quoted(argv);
	if (res)
		res = BISECT_FAILED;

finish:
	string_list_clear(&revs, 0);
	string_list_clear(&states, 0);
	strbuf_release(&start_head);
	strbuf_release(&bisect_names);
	if (res)
		return res;

	res = bisect_auto_next(terms, NULL);
	if (!is_bisect_success(res))
		bisect_clean_state();
	return res;
}

static inline int file_is_not_empty(const char *path)
{
	return !is_empty_or_missing_file(path);
}

static int bisect_autostart(struct bisect_terms *terms)
{
	int res;
	const char *yesno;

	if (file_is_not_empty(git_path_bisect_start()))
		return 0;

	fprintf_ln(stderr, _("You need to start by \"git bisect "
			  "start\"\n"));

	if (!isatty(STDIN_FILENO))
		return -1;

	/*
	 * TRANSLATORS: Make sure to include [Y] and [n] in your
	 * translation. The program will only accept English input
	 * at this point.
	 */
	yesno = git_prompt(_("Do you want me to do it for you "
			     "[Y/n]? "), PROMPT_ECHO);
	res = tolower(*yesno) == 'n' ?
		-1 : bisect_start(terms, 0, empty_strvec);

	return res;
}

static enum bisect_error bisect_state(struct bisect_terms *terms, int argc,
				      const char **argv)
{
	const char *state;
	int i, verify_expected = 1;
	struct object_id oid, expected;
	struct strbuf buf = STRBUF_INIT;
	struct oid_array revs = OID_ARRAY_INIT;

	if (!argc)
		return error(_("Please call `--bisect-state` with at least one argument"));

	if (bisect_autostart(terms))
		return BISECT_FAILED;

	state = argv[0];
	if (check_and_set_terms(terms, state) ||
	    !one_of(state, terms->term_good, terms->term_bad, "skip", NULL))
		return BISECT_FAILED;

	argv++;
	argc--;
	if (argc > 1 && !strcmp(state, terms->term_bad))
		return error(_("'git bisect %s' can take only one argument."), terms->term_bad);

	if (argc == 0) {
		const char *head = "BISECT_HEAD";
		enum get_oid_result res_head = repo_get_oid(the_repository,
							    head, &oid);

		if (res_head == MISSING_OBJECT) {
			head = "HEAD";
			res_head = repo_get_oid(the_repository, head, &oid);
		}

		if (res_head)
			error(_("Bad rev input: %s"), head);
		oid_array_append(&revs, &oid);
	}

	/*
	 * All input revs must be checked before executing bisect_write()
	 * to discard junk revs.
	 */

	for (; argc; argc--, argv++) {
		struct commit *commit;

		if (repo_get_oid(the_repository, *argv, &oid)){
			error(_("Bad rev input: %s"), *argv);
			oid_array_clear(&revs);
			return BISECT_FAILED;
		}

		commit = lookup_commit_reference(the_repository, &oid);
		if (!commit)
			die(_("Bad rev input (not a commit): %s"), *argv);

		oid_array_append(&revs, &commit->object.oid);
	}

	if (strbuf_read_file(&buf, git_path_bisect_expected_rev(), 0) < the_hash_algo->hexsz ||
	    get_oid_hex(buf.buf, &expected) < 0)
		verify_expected = 0; /* Ignore invalid file contents */
	strbuf_release(&buf);

	for (i = 0; i < revs.nr; i++) {
		if (bisect_write(state, oid_to_hex(&revs.oid[i]), terms, 0)) {
			oid_array_clear(&revs);
			return BISECT_FAILED;
		}
		if (verify_expected && !oideq(&revs.oid[i], &expected)) {
			unlink_or_warn(git_path_bisect_ancestors_ok());
			unlink_or_warn(git_path_bisect_expected_rev());
			verify_expected = 0;
		}
	}

	oid_array_clear(&revs);
	return bisect_auto_next(terms, NULL);
}

static enum bisect_error bisect_log(void)
{
	int fd, status;
	const char* filename = git_path_bisect_log();

	if (is_empty_or_missing_file(filename))
		return error(_("We are not bisecting."));

	fd = open(filename, O_RDONLY);
	if (fd < 0)
		return BISECT_FAILED;

	status = copy_fd(fd, STDOUT_FILENO);
	close(fd);
	return status ? BISECT_FAILED : BISECT_OK;
}

static int process_replay_line(struct bisect_terms *terms, struct strbuf *line)
{
	const char *p = line->buf + strspn(line->buf, " \t");
	char *word_end, *rev;

	if ((!skip_prefix(p, "git bisect", &p) &&
	!skip_prefix(p, "git-bisect", &p)) || !isspace(*p))
		return 0;
	p += strspn(p, " \t");

	word_end = (char *)p + strcspn(p, " \t");
	rev = word_end + strspn(word_end, " \t");
	*word_end = '\0'; /* NUL-terminate the word */

	get_terms(terms);
	if (check_and_set_terms(terms, p))
		return -1;

	if (!strcmp(p, "start")) {
		struct strvec argv = STRVEC_INIT;
		int res;
		sq_dequote_to_strvec(rev, &argv);
		res = bisect_start(terms, argv.nr, argv.v);
		strvec_clear(&argv);
		return res;
	}

	if (one_of(p, terms->term_good,
	   terms->term_bad, "skip", NULL))
		return bisect_write(p, rev, terms, 0);

	if (!strcmp(p, "terms")) {
		struct strvec argv = STRVEC_INIT;
		int res;
		sq_dequote_to_strvec(rev, &argv);
		res = bisect_terms(terms, argv.nr == 1 ? argv.v[0] : NULL);
		strvec_clear(&argv);
		return res;
	}
	error(_("'%s'?? what are you talking about?"), p);

	return -1;
}

static enum bisect_error bisect_replay(struct bisect_terms *terms, const char *filename)
{
	FILE *fp = NULL;
	enum bisect_error res = BISECT_OK;
	struct strbuf line = STRBUF_INIT;

	if (is_empty_or_missing_file(filename))
		return error(_("cannot read file '%s' for replaying"), filename);

	if (bisect_reset(NULL))
		return BISECT_FAILED;

	fp = fopen(filename, "r");
	if (!fp)
		return BISECT_FAILED;

	while ((strbuf_getline(&line, fp) != EOF) && !res)
		res = process_replay_line(terms, &line);

	strbuf_release(&line);
	fclose(fp);

	if (res)
		return BISECT_FAILED;

	return bisect_auto_next(terms, NULL);
}

static enum bisect_error bisect_skip(struct bisect_terms *terms, int argc,
				     const char **argv)
{
	int i;
	enum bisect_error res;
	struct strvec argv_state = STRVEC_INIT;

	strvec_push(&argv_state, "skip");

	for (i = 0; i < argc; i++) {
		const char *dotdot = strstr(argv[i], "..");

		if (dotdot) {
			struct rev_info revs;
			struct commit *commit;

			repo_init_revisions(the_repository, &revs, NULL);
			setup_revisions(2, argv + i - 1, &revs, NULL);

			if (prepare_revision_walk(&revs))
				die(_("revision walk setup failed\n"));
			while ((commit = get_revision(&revs)) != NULL)
				strvec_push(&argv_state,
						oid_to_hex(&commit->object.oid));

			reset_revision_walk();
			release_revisions(&revs);
		} else {
			strvec_push(&argv_state, argv[i]);
		}
	}
	res = bisect_state(terms, argv_state.nr, argv_state.v);

	strvec_clear(&argv_state);
	return res;
}

static int bisect_visualize(struct bisect_terms *terms, int argc,
			    const char **argv)
{
	struct child_process cmd = CHILD_PROCESS_INIT;
	struct strbuf sb = STRBUF_INIT;

	if (bisect_next_check(terms, NULL) != 0)
		return BISECT_FAILED;

	cmd.no_stdin = 1;
	if (!argc) {
		if ((getenv("DISPLAY") || getenv("SESSIONNAME") || getenv("MSYSTEM") ||
		     getenv("SECURITYSESSIONID")) && exists_in_PATH("gitk")) {
			strvec_push(&cmd.args, "gitk");
		} else {
			strvec_push(&cmd.args, "log");
			cmd.git_cmd = 1;
		}
	} else {
		if (argv[0][0] == '-') {
			strvec_push(&cmd.args, "log");
			cmd.git_cmd = 1;
		} else if (strcmp(argv[0], "tig") && !starts_with(argv[0], "git"))
			cmd.git_cmd = 1;

		strvec_pushv(&cmd.args, argv);
	}

	strvec_pushl(&cmd.args, "--bisect", "--", NULL);

	strbuf_read_file(&sb, git_path_bisect_names(), 0);
	sq_dequote_to_strvec(sb.buf, &cmd.args);
	strbuf_release(&sb);

	return run_command(&cmd);
}

static int get_first_good(const char *refname UNUSED,
			  const struct object_id *oid,
			  int flag UNUSED, void *cb_data)
{
	oidcpy(cb_data, oid);
	return 1;
}

static int do_bisect_run(const char *command)
{
	struct child_process cmd = CHILD_PROCESS_INIT;

	printf(_("running %s\n"), command);
	cmd.use_shell = 1;
	strvec_push(&cmd.args, command);
	return run_command(&cmd);
}

static int verify_good(const struct bisect_terms *terms, const char *command)
{
	int rc;
	enum bisect_error res;
	struct object_id good_rev;
	struct object_id current_rev;
	char *good_glob = xstrfmt("%s-*", terms->term_good);
	int no_checkout = ref_exists("BISECT_HEAD");

	for_each_glob_ref_in(get_first_good, good_glob, "refs/bisect/",
			     &good_rev);
	free(good_glob);

	if (read_ref(no_checkout ? "BISECT_HEAD" : "HEAD", &current_rev))
		return -1;

	res = bisect_checkout(&good_rev, no_checkout);
	if (res != BISECT_OK)
		return -1;

	rc = do_bisect_run(command);

	res = bisect_checkout(&current_rev, no_checkout);
	if (res != BISECT_OK)
		return -1;

	return rc;
}

static int bisect_run(struct bisect_terms *terms, int argc, const char **argv)
{
	int res = BISECT_OK;
	struct strbuf command = STRBUF_INIT;
	const char *new_state;
	int temporary_stdout_fd, saved_stdout;
	int is_first_run = 1;

	if (bisect_next_check(terms, NULL))
		return BISECT_FAILED;

	if (!argc) {
		error(_("bisect run failed: no command provided."));
		return BISECT_FAILED;
	}

	sq_quote_argv(&command, argv);
	strbuf_ltrim(&command);
	while (1) {
		res = do_bisect_run(command.buf);

		/*
		 * Exit code 126 and 127 can either come from the shell
		 * if it was unable to execute or even find the script,
		 * or from the script itself.  Check with a known-good
		 * revision to avoid trashing the bisect run due to a
		 * missing or non-executable script.
		 */
		if (is_first_run && (res == 126 || res == 127)) {
			int rc = verify_good(terms, command.buf);
			is_first_run = 0;
			if (rc < 0 || 128 <= rc) {
				error(_("unable to verify %s on good"
					" revision"), command.buf);
				res = BISECT_FAILED;
				break;
			}
			if (rc == res) {
				error(_("bogus exit code %d for good revision"),
				      rc);
				res = BISECT_FAILED;
				break;
			}
		}

		if (res < 0 || 128 <= res) {
			error(_("bisect run failed: exit code %d from"
				" %s is < 0 or >= 128"), res, command.buf);
			break;
		}

		if (res == 125)
			new_state = "skip";
		else if (!res)
			new_state = terms->term_good;
		else
			new_state = terms->term_bad;

		temporary_stdout_fd = open(git_path_bisect_run(), O_CREAT | O_WRONLY | O_TRUNC, 0666);

		if (temporary_stdout_fd < 0) {
			res = error_errno(_("cannot open file '%s' for writing"), git_path_bisect_run());
			break;
		}

		fflush(stdout);
		saved_stdout = dup(1);
		dup2(temporary_stdout_fd, 1);

		res = bisect_state(terms, 1, &new_state);

		fflush(stdout);
		dup2(saved_stdout, 1);
		close(saved_stdout);
		close(temporary_stdout_fd);

		print_file_to_stdout(git_path_bisect_run());

		if (res == BISECT_ONLY_SKIPPED_LEFT)
			error(_("bisect run cannot continue any more"));
		else if (res == BISECT_INTERNAL_SUCCESS_MERGE_BASE) {
			puts(_("bisect run success"));
			res = BISECT_OK;
		} else if (res == BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND) {
			puts(_("bisect found first bad commit"));
			res = BISECT_OK;
		} else if (res) {
			error(_("bisect run failed: 'git bisect %s'"
				" exited with error code %d"), new_state, res);
		} else {
			continue;
		}
		break;
	}

	strbuf_release(&command);
	return res;
}

static int cmd_bisect__reset(int argc, const char **argv, const char *prefix UNUSED)
{
	if (argc > 1)
		return error(_("'%s' requires either no argument or a commit"),
			     "git bisect reset");
	return bisect_reset(argc ? argv[0] : NULL);
}

static int cmd_bisect__terms(int argc, const char **argv, const char *prefix UNUSED)
{
	int res;
	struct bisect_terms terms = { 0 };

	if (argc > 1)
		return error(_("'%s' requires 0 or 1 argument"),
			     "git bisect terms");
	res = bisect_terms(&terms, argc == 1 ? argv[0] : NULL);
	free_terms(&terms);
	return res;
}

static int cmd_bisect__start(int argc, const char **argv, const char *prefix UNUSED)
{
	int res;
	struct bisect_terms terms = { 0 };

	set_terms(&terms, "bad", "good");
	res = bisect_start(&terms, argc, argv);
	free_terms(&terms);
	return res;
}

static int cmd_bisect__next(int argc, const char **argv UNUSED, const char *prefix)
{
	int res;
	struct bisect_terms terms = { 0 };

	if (argc)
		return error(_("'%s' requires 0 arguments"),
			     "git bisect next");
	get_terms(&terms);
	res = bisect_next(&terms, prefix);
	free_terms(&terms);
	return res;
}

static int cmd_bisect__log(int argc UNUSED, const char **argv UNUSED, const char *prefix UNUSED)
{
	return bisect_log();
}

static int cmd_bisect__replay(int argc, const char **argv, const char *prefix UNUSED)
{
	int res;
	struct bisect_terms terms = { 0 };

	if (argc != 1)
		return error(_("no logfile given"));
	set_terms(&terms, "bad", "good");
	res = bisect_replay(&terms, argv[0]);
	free_terms(&terms);
	return res;
}

static int cmd_bisect__skip(int argc, const char **argv, const char *prefix UNUSED)
{
	int res;
	struct bisect_terms terms = { 0 };

	set_terms(&terms, "bad", "good");
	get_terms(&terms);
	res = bisect_skip(&terms, argc, argv);
	free_terms(&terms);
	return res;
}

static int cmd_bisect__visualize(int argc, const char **argv, const char *prefix UNUSED)
{
	int res;
	struct bisect_terms terms = { 0 };

	get_terms(&terms);
	res = bisect_visualize(&terms, argc, argv);
	free_terms(&terms);
	return res;
}

static int cmd_bisect__run(int argc, const char **argv, const char *prefix UNUSED)
{
	int res;
	struct bisect_terms terms = { 0 };

	if (!argc)
		return error(_("'%s' failed: no command provided."), "git bisect run");
	get_terms(&terms);
	res = bisect_run(&terms, argc, argv);
	free_terms(&terms);
	return res;
}

int cmd_bisect(int argc, const char **argv, const char *prefix)
{
	int res = 0;
	parse_opt_subcommand_fn *fn = NULL;
	struct option options[] = {
		OPT_SUBCOMMAND("reset", &fn, cmd_bisect__reset),
		OPT_SUBCOMMAND("terms", &fn, cmd_bisect__terms),
		OPT_SUBCOMMAND("start", &fn, cmd_bisect__start),
		OPT_SUBCOMMAND("next", &fn, cmd_bisect__next),
		OPT_SUBCOMMAND("log", &fn, cmd_bisect__log),
		OPT_SUBCOMMAND("replay", &fn, cmd_bisect__replay),
		OPT_SUBCOMMAND("skip", &fn, cmd_bisect__skip),
		OPT_SUBCOMMAND("visualize", &fn, cmd_bisect__visualize),
		OPT_SUBCOMMAND("view", &fn, cmd_bisect__visualize),
		OPT_SUBCOMMAND("run", &fn, cmd_bisect__run),
		OPT_END()
	};
	argc = parse_options(argc, argv, prefix, options, git_bisect_usage,
			     PARSE_OPT_SUBCOMMAND_OPTIONAL);

	if (!fn) {
		struct bisect_terms terms = { 0 };

		if (!argc)
			usage_msg_opt(_("need a command"), git_bisect_usage, options);

		set_terms(&terms, "bad", "good");
		get_terms(&terms);
		if (check_and_set_terms(&terms, argv[0]))
			usage_msg_optf(_("unknown command: '%s'"), git_bisect_usage,
				       options, argv[0]);
		res = bisect_state(&terms, argc, argv);
		free_terms(&terms);
	} else {
		argc--;
		argv++;
		res = fn(argc, argv, prefix);
	}

	return is_bisect_success(res) ? 0 : -res;
}