git@vger.kernel.org list mirror (unofficial, one of many)
 help / color / mirror / code / Atom feed
a976f4739c879f20a274780df4b485bc82622cbf blob 28843 bytes (raw)

   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
 
#include "builtin.h"
#include "cache.h"
#include "parse-options.h"
#include "bisect.h"
#include "refs.h"
#include "dir.h"
#include "strvec.h"
#include "run-command.h"
#include "prompt.h"
#include "quote.h"
#include "revision.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_head_name, "head-name")
static GIT_PATH_FUNC(git_path_bisect_names, "BISECT_NAMES")
static GIT_PATH_FUNC(git_path_bisect_first_parent, "BISECT_FIRST_PARENT")

static const char * const git_bisect_helper_usage[] = {
	N_("git bisect--helper --write-terms <bad_term> <good_term>"),
	N_("git bisect--helper --bisect-reset [<commit>]"),
	N_("git bisect--helper --bisect-write [--no-log] <state> <revision> <good_term> <bad_term>"),
	N_("git bisect--helper --bisect-check-and-set-terms <command> <good_term> <bad_term>"),
	N_("git bisect--helper --bisect-next-check <good_term> <bad_term> [<term>]"),
	N_("git bisect--helper --bisect-terms [--term-good | --term-old | --term-bad | --term-new]"),
	N_("git bisect--helper --bisect-start [--term-{old,good}=<term> --term-{new,bad}=<term>]"
					    " [--no-checkout] [--first-parent] [<bad> [<good>...]] [--] [<paths>...]"),
	N_("git bisect--helper --bisect-next"),
	N_("git bisect--helper --bisect-auto-next"),
	N_("git bisect--helper --bisect-autostart"),
	N_("git bisect--helper --bisect-state (bad|new) [<rev>]"),
	N_("git bisect--helper --bisect-state (good|old) [<rev>...]"),
	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);
}

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;
}

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 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 is_expected_rev(const char *expected_hex)
{
	struct strbuf actual_hex = STRBUF_INIT;
	int res = 0;
	if (strbuf_read_file(&actual_hex, git_path_bisect_expected_rev(), 0) >= 40) {
		strbuf_trim(&actual_hex);
		res = !strcmp(actual_hex.buf, expected_hex);
	}
	strbuf_release(&actual_hex);
	return res;
}

static void check_expected_revs(const char **revs, int rev_nr)
{
	int i;

	for (i = 0; i < rev_nr; i++) {
		if (!is_expected_rev(revs[i])) {
			unlink_or_warn(git_path_bisect_ancestors_ok());
			unlink_or_warn(git_path_bisect_expected_rev());
		}
	}
}

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

	if (!ref_exists("BISECT_HEAD")) {
		struct strvec argv = STRVEC_INIT;

		strvec_pushl(&argv, "checkout", branch.buf, "--", NULL);
		if (run_command_v_opt(argv.v, RUN_GIT_CMD)) {
			error(_("could not check out original"
				" HEAD '%s'. Try 'git bisect"
				" reset <commit>'."), branch.buf);
			strbuf_release(&branch);
			strvec_clear(&argv);
			return -1;
		}
		strvec_clear(&argv);
	}

	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);

	format_commit_message(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 (get_oid(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 mark_good(const char *refname, const struct object_id *oid,
		     int flag, void *cb_data)
{
	int *m_good = (int *)cb_data;
	*m_good = 0;
	return 1;
}

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 int bisect_next_check(const struct bisect_terms *terms,
			     const char *current_term)
{
	int missing_good = 1, missing_bad = 1;
	char *bad_ref = xstrfmt("refs/bisect/%s", terms->term_bad);
	char *good_glob = xstrfmt("%s-*", terms->term_good);

	if (ref_exists(bad_ref))
		missing_bad = 0;

	for_each_glob_ref_in(mark_good, good_glob, "refs/bisect/",
			     (void *) &missing_good);

	free(good_glob);
	free(bad_ref);

	return decide_next(terms, current_term, missing_good, missing_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 == NULL) {
		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, 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();
	init_revisions(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);
		format_commit_message(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);
	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);
	format_commit_message(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;

	bisect_autostart(terms);
	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))
		return BISECT_OK;

	return bisect_next(terms, prefix);
}

static enum bisect_error bisect_start(struct bisect_terms *terms, const char **argv, int argc)
{
	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 {
			char *commit_id = xstrfmt("%s^{commit}", arg);
			if (get_oid(commit_id, &oid) && has_double_dash) {
				error(_("'%s' does not appear to be a valid "
					"revision"), arg);
				free(commit_id);
				return BISECT_FAILED;
			}

			string_list_append(&revs, oid_to_hex(&oid));
			free(commit_id);
		}
	}
	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 (get_oid("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 strvec argv = STRVEC_INIT;

			strvec_pushl(&argv, "checkout", start_head.buf,
				     "--", NULL);
			if (run_command_v_opt(argv.v, RUN_GIT_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 (!get_oid(head, &head_oid) &&
		    !starts_with(head, "refs/heads/")) {
			strbuf_reset(&start_head);
			strbuf_addstr(&start_head, oid_to_hex(&head_oid));
		} else if (!get_oid(head, &head_oid) &&
			   skip_prefix(head, "refs/heads/", &head)) {
			/*
			 * This error message should only be triggered by
			 * cogito usage, and cogito users should understand
			 * it relates to cg-seek.
			 */
			if (!is_empty_or_missing_file(git_path_head_name()))
				return error(_("won't bisect on cg-seek'ed tree"));
			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 (get_oid(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);
	/*
	 * In case of mistaken revs or checkout error,
	 * "bisect_auto_next" above may exit or misbehave.
	 * We have to handle this to be able to clean up using
	 * "bisect_clean_state".
	 */
	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 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(_("Do you want me to do it for you "
			     "[Y/n]? "), PROMPT_ECHO);
	res = tolower(*yesno) == 'n' ?
		-1 : bisect_start(terms, empty_strvec, 0);

	return res;
}

static enum bisect_error bisect_state(struct bisect_terms *terms, const char **argv,
				      int argc)
{
	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"));

	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) {
		enum get_oid_result res_head = get_oid("BISECT_HEAD", &oid);
		if (res_head == MISSING_OBJECT)
			res_head = get_oid("HEAD", &oid);
		if (res_head) {
			error(_("Bad bisect_head rev input"));
			return BISECT_FAILED;
		}
		oid_array_append(&revs, &oid);
	}

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

	for (; argc; argc--, argv++) {
		if (get_oid(*argv, &oid)){
			error(_("Bad rev input: %s"), *argv);
			return BISECT_FAILED;
		}
		oid_array_append(&revs, &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))
			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);
}

int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
{
	enum {
		WRITE_TERMS = 1,
		CHECK_EXPECTED_REVS,
		BISECT_RESET,
		BISECT_WRITE,
		CHECK_AND_SET_TERMS,
		BISECT_NEXT_CHECK,
		BISECT_TERMS,
		BISECT_START,
		BISECT_NEXT,
		BISECT_AUTO_NEXT,
		BISECT_AUTOSTART,
		BISECT_STATE
	} cmdmode = 0;
	int res = 0, nolog = 0;
	struct option options[] = {
		OPT_CMDMODE(0, "write-terms", &cmdmode,
			 N_("write the terms to .git/BISECT_TERMS"), WRITE_TERMS),
		OPT_CMDMODE(0, "check-expected-revs", &cmdmode,
			 N_("check for expected revs"), CHECK_EXPECTED_REVS),
		OPT_CMDMODE(0, "bisect-reset", &cmdmode,
			 N_("reset the bisection state"), BISECT_RESET),
		OPT_CMDMODE(0, "bisect-write", &cmdmode,
			 N_("write out the bisection state in BISECT_LOG"), BISECT_WRITE),
		OPT_CMDMODE(0, "check-and-set-terms", &cmdmode,
			 N_("check and set terms in a bisection state"), CHECK_AND_SET_TERMS),
		OPT_CMDMODE(0, "bisect-next-check", &cmdmode,
			 N_("check whether bad or good terms exist"), BISECT_NEXT_CHECK),
		OPT_CMDMODE(0, "bisect-terms", &cmdmode,
			 N_("print out the bisect terms"), BISECT_TERMS),
		OPT_CMDMODE(0, "bisect-start", &cmdmode,
			 N_("start the bisect session"), BISECT_START),
		OPT_CMDMODE(0, "bisect-next", &cmdmode,
			 N_("find the next bisection commit"), BISECT_NEXT),
		OPT_CMDMODE(0, "bisect-auto-next", &cmdmode,
			 N_("verify the next bisection state then checkout the next bisection commit"), BISECT_AUTO_NEXT),
		OPT_CMDMODE(0, "bisect-autostart", &cmdmode,
			 N_("start the bisection if it has not yet been started"), BISECT_AUTOSTART),
		OPT_CMDMODE(0, "bisect-state", &cmdmode,
			 N_("mark the state of ref (or refs)"), BISECT_STATE),
		OPT_BOOL(0, "no-log", &nolog,
			 N_("no log for BISECT_WRITE")),
		OPT_END()
	};
	struct bisect_terms terms = { .term_good = NULL, .term_bad = NULL };

	argc = parse_options(argc, argv, prefix, options,
			     git_bisect_helper_usage,
			     PARSE_OPT_KEEP_DASHDASH | PARSE_OPT_KEEP_UNKNOWN);

	if (!cmdmode)
		usage_with_options(git_bisect_helper_usage, options);

	switch (cmdmode) {
	case WRITE_TERMS:
		if (argc != 2)
			return error(_("--write-terms requires two arguments"));
		return write_terms(argv[0], argv[1]);
	case CHECK_EXPECTED_REVS:
		check_expected_revs(argv, argc);
		return 0;
	case BISECT_RESET:
		if (argc > 1)
			return error(_("--bisect-reset requires either no argument or a commit"));
		return !!bisect_reset(argc ? argv[0] : NULL);
	case BISECT_WRITE:
		if (argc != 4 && argc != 5)
			return error(_("--bisect-write requires either 4 or 5 arguments"));
		set_terms(&terms, argv[3], argv[2]);
		res = bisect_write(argv[0], argv[1], &terms, nolog);
		break;
	case CHECK_AND_SET_TERMS:
		if (argc != 3)
			return error(_("--check-and-set-terms requires 3 arguments"));
		set_terms(&terms, argv[2], argv[1]);
		res = check_and_set_terms(&terms, argv[0]);
		break;
	case BISECT_NEXT_CHECK:
		if (argc != 2 && argc != 3)
			return error(_("--bisect-next-check requires 2 or 3 arguments"));
		set_terms(&terms, argv[1], argv[0]);
		res = bisect_next_check(&terms, argc == 3 ? argv[2] : NULL);
		break;
	case BISECT_TERMS:
		if (argc > 1)
			return error(_("--bisect-terms requires 0 or 1 argument"));
		res = bisect_terms(&terms, argc == 1 ? argv[0] : NULL);
		break;
	case BISECT_START:
		set_terms(&terms, "bad", "good");
		res = bisect_start(&terms, argv, argc);
		break;
	case BISECT_NEXT:
		if (argc)
			return error(_("--bisect-next requires 0 arguments"));
		get_terms(&terms);
		res = bisect_next(&terms, prefix);
		break;
	case BISECT_AUTO_NEXT:
		if (argc)
			return error(_("--bisect-auto-next requires 0 arguments"));
		get_terms(&terms);
		res = bisect_auto_next(&terms, prefix);
		break;
	case BISECT_AUTOSTART:
		if (argc)
			return error(_("--bisect-autostart does not accept arguments"));
		set_terms(&terms, "bad", "good");
		res = bisect_autostart(&terms);
		break;
	case BISECT_STATE:
		set_terms(&terms, "bad", "good");
		get_terms(&terms);
		res = bisect_state(&terms, argv, argc);
		break;
	default:
		BUG("unknown subcommand %d", cmdmode);
	}
	free_terms(&terms);

	/*
	 * Handle early success
	 * From check_merge_bases > check_good_are_ancestors_of_bad > bisect_next_all
	 */
	if ((res == BISECT_INTERNAL_SUCCESS_MERGE_BASE) || (res == BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND))
		res = BISECT_OK;

	return -res;
}
debug log:

solving a976f4739c ...
found a976f4739c in https://public-inbox.org/git/20200831105043.97665-11-mirucam@gmail.com/
found 0796e51672 in https://public-inbox.org/git/20200831105043.97665-10-mirucam@gmail.com/
found b8b8a7473c in https://public-inbox.org/git/20200831105043.97665-9-mirucam@gmail.com/
found b40369e8aa in https://public-inbox.org/git/20200831105043.97665-8-mirucam@gmail.com/
found e29e86142a in https://public-inbox.org/git/20200831105043.97665-7-mirucam@gmail.com/
found f71e8e54d2 in https://public-inbox.org/git/20200831105043.97665-5-mirucam@gmail.com/ ||
	https://public-inbox.org/git/20200828124617.60618-5-mirucam@gmail.com/
found bae09ce65d in git.git.git
preparing index
index prepared:
100644 bae09ce65dc94fb9125e385c1a12be1d3faa9b01	builtin/bisect--helper.c

applying [1/7] https://public-inbox.org/git/20200831105043.97665-5-mirucam@gmail.com/
diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
index bae09ce65d..f71e8e54d2 100644

Checking patch builtin/bisect--helper.c...
Applied patch builtin/bisect--helper.c cleanly.

skipping https://public-inbox.org/git/20200828124617.60618-5-mirucam@gmail.com/ for f71e8e54d2
index at:
100644 f71e8e54d2817a9f762fd85bc1226c31f7113d49	builtin/bisect--helper.c

applying [2/7] https://public-inbox.org/git/20200831105043.97665-7-mirucam@gmail.com/
diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
index f71e8e54d2..e29e86142a 100644


applying [3/7] https://public-inbox.org/git/20200831105043.97665-8-mirucam@gmail.com/
diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
index e29e86142a..b40369e8aa 100644


applying [4/7] https://public-inbox.org/git/20200831105043.97665-9-mirucam@gmail.com/
diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
index b40369e8aa..b8b8a7473c 100644


applying [5/7] https://public-inbox.org/git/20200831105043.97665-10-mirucam@gmail.com/
diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
index b8b8a7473c..0796e51672 100644


applying [6/7] https://public-inbox.org/git/20200831105043.97665-11-mirucam@gmail.com/
diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
index 0796e51672..a976f4739c 100644

Checking patch builtin/bisect--helper.c...
Applied patch builtin/bisect--helper.c cleanly.
Checking patch builtin/bisect--helper.c...
Applied patch builtin/bisect--helper.c cleanly.
Checking patch builtin/bisect--helper.c...
Applied patch builtin/bisect--helper.c cleanly.
Checking patch builtin/bisect--helper.c...
Applied patch builtin/bisect--helper.c cleanly.
Checking patch builtin/bisect--helper.c...
Applied patch builtin/bisect--helper.c cleanly.

index at:
100644 a976f4739c879f20a274780df4b485bc82622cbf	builtin/bisect--helper.c

Code repositories for project(s) associated with this inbox:

	https://80x24.org/mirrors/git.git

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).