Source

git / revision.c

   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
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
#include "cache.h"
#include "tag.h"
#include "blob.h"
#include "tree.h"
#include "commit.h"
#include "diff.h"
#include "refs.h"
#include "revision.h"
#include "graph.h"
#include "grep.h"
#include "reflog-walk.h"
#include "patch-ids.h"
#include "decorate.h"

volatile show_early_output_fn_t show_early_output;

static char *path_name(struct name_path *path, const char *name)
{
	struct name_path *p;
	char *n, *m;
	int nlen = strlen(name);
	int len = nlen + 1;

	for (p = path; p; p = p->up) {
		if (p->elem_len)
			len += p->elem_len + 1;
	}
	n = xmalloc(len);
	m = n + len - (nlen + 1);
	strcpy(m, name);
	for (p = path; p; p = p->up) {
		if (p->elem_len) {
			m -= p->elem_len + 1;
			memcpy(m, p->elem, p->elem_len);
			m[p->elem_len] = '/';
		}
	}
	return n;
}

void add_object(struct object *obj,
		struct object_array *p,
		struct name_path *path,
		const char *name)
{
	add_object_array(obj, path_name(path, name), p);
}

static void mark_blob_uninteresting(struct blob *blob)
{
	if (!blob)
		return;
	if (blob->object.flags & UNINTERESTING)
		return;
	blob->object.flags |= UNINTERESTING;
}

void mark_tree_uninteresting(struct tree *tree)
{
	struct tree_desc desc;
	struct name_entry entry;
	struct object *obj = &tree->object;

	if (!tree)
		return;
	if (obj->flags & UNINTERESTING)
		return;
	obj->flags |= UNINTERESTING;
	if (!has_sha1_file(obj->sha1))
		return;
	if (parse_tree(tree) < 0)
		die("bad tree %s", sha1_to_hex(obj->sha1));

	init_tree_desc(&desc, tree->buffer, tree->size);
	while (tree_entry(&desc, &entry)) {
		switch (object_type(entry.mode)) {
		case OBJ_TREE:
			mark_tree_uninteresting(lookup_tree(entry.sha1));
			break;
		case OBJ_BLOB:
			mark_blob_uninteresting(lookup_blob(entry.sha1));
			break;
		default:
			/* Subproject commit - not in this repository */
			break;
		}
	}

	/*
	 * We don't care about the tree any more
	 * after it has been marked uninteresting.
	 */
	free(tree->buffer);
	tree->buffer = NULL;
}

void mark_parents_uninteresting(struct commit *commit)
{
	struct commit_list *parents = commit->parents;

	while (parents) {
		struct commit *commit = parents->item;
		if (!(commit->object.flags & UNINTERESTING)) {
			commit->object.flags |= UNINTERESTING;

			/*
			 * Normally we haven't parsed the parent
			 * yet, so we won't have a parent of a parent
			 * here. However, it may turn out that we've
			 * reached this commit some other way (where it
			 * wasn't uninteresting), in which case we need
			 * to mark its parents recursively too..
			 */
			if (commit->parents)
				mark_parents_uninteresting(commit);
		}

		/*
		 * A missing commit is ok iff its parent is marked
		 * uninteresting.
		 *
		 * We just mark such a thing parsed, so that when
		 * it is popped next time around, we won't be trying
		 * to parse it and get an error.
		 */
		if (!has_sha1_file(commit->object.sha1))
			commit->object.parsed = 1;
		parents = parents->next;
	}
}

static void add_pending_object_with_mode(struct rev_info *revs, struct object *obj, const char *name, unsigned mode)
{
	if (revs->no_walk && (obj->flags & UNINTERESTING))
		die("object ranges do not make sense when not walking revisions");
	if (revs->reflog_info && obj->type == OBJ_COMMIT &&
			add_reflog_for_walk(revs->reflog_info,
				(struct commit *)obj, name))
		return;
	add_object_array_with_mode(obj, name, &revs->pending, mode);
}

void add_pending_object(struct rev_info *revs, struct object *obj, const char *name)
{
	add_pending_object_with_mode(revs, obj, name, S_IFINVALID);
}

void add_head_to_pending(struct rev_info *revs)
{
	unsigned char sha1[20];
	struct object *obj;
	if (get_sha1("HEAD", sha1))
		return;
	obj = parse_object(sha1);
	if (!obj)
		return;
	add_pending_object(revs, obj, "HEAD");
}

static struct object *get_reference(struct rev_info *revs, const char *name, const unsigned char *sha1, unsigned int flags)
{
	struct object *object;

	object = parse_object(sha1);
	if (!object)
		die("bad object %s", name);
	object->flags |= flags;
	return object;
}

static struct commit *handle_commit(struct rev_info *revs, struct object *object, const char *name)
{
	unsigned long flags = object->flags;

	/*
	 * Tag object? Look what it points to..
	 */
	while (object->type == OBJ_TAG) {
		struct tag *tag = (struct tag *) object;
		if (revs->tag_objects && !(flags & UNINTERESTING))
			add_pending_object(revs, object, tag->tag);
		if (!tag->tagged)
			die("bad tag");
		object = parse_object(tag->tagged->sha1);
		if (!object)
			die("bad object %s", sha1_to_hex(tag->tagged->sha1));
	}

	/*
	 * Commit object? Just return it, we'll do all the complex
	 * reachability crud.
	 */
	if (object->type == OBJ_COMMIT) {
		struct commit *commit = (struct commit *)object;
		if (parse_commit(commit) < 0)
			die("unable to parse commit %s", name);
		if (flags & UNINTERESTING) {
			commit->object.flags |= UNINTERESTING;
			mark_parents_uninteresting(commit);
			revs->limited = 1;
		}
		return commit;
	}

	/*
	 * Tree object? Either mark it uniniteresting, or add it
	 * to the list of objects to look at later..
	 */
	if (object->type == OBJ_TREE) {
		struct tree *tree = (struct tree *)object;
		if (!revs->tree_objects)
			return NULL;
		if (flags & UNINTERESTING) {
			mark_tree_uninteresting(tree);
			return NULL;
		}
		add_pending_object(revs, object, "");
		return NULL;
	}

	/*
	 * Blob object? You know the drill by now..
	 */
	if (object->type == OBJ_BLOB) {
		struct blob *blob = (struct blob *)object;
		if (!revs->blob_objects)
			return NULL;
		if (flags & UNINTERESTING) {
			mark_blob_uninteresting(blob);
			return NULL;
		}
		add_pending_object(revs, object, "");
		return NULL;
	}
	die("%s is unknown object", name);
}

static int everybody_uninteresting(struct commit_list *orig)
{
	struct commit_list *list = orig;
	while (list) {
		struct commit *commit = list->item;
		list = list->next;
		if (commit->object.flags & UNINTERESTING)
			continue;
		return 0;
	}
	return 1;
}

/*
 * The goal is to get REV_TREE_NEW as the result only if the
 * diff consists of all '+' (and no other changes), and
 * REV_TREE_DIFFERENT otherwise (of course if the trees are
 * the same we want REV_TREE_SAME).  That means that once we
 * get to REV_TREE_DIFFERENT, we do not have to look any further.
 */
static int tree_difference = REV_TREE_SAME;

static void file_add_remove(struct diff_options *options,
		    int addremove, unsigned mode,
		    const unsigned char *sha1,
		    const char *fullpath)
{
	int diff = REV_TREE_DIFFERENT;

	/*
	 * Is it an add of a new file? It means that the old tree
	 * didn't have it at all, so we will turn "REV_TREE_SAME" ->
	 * "REV_TREE_NEW", but leave any "REV_TREE_DIFFERENT" alone
	 * (and if it already was "REV_TREE_NEW", we'll keep it
	 * "REV_TREE_NEW" of course).
	 */
	if (addremove == '+') {
		diff = tree_difference;
		if (diff != REV_TREE_SAME)
			return;
		diff = REV_TREE_NEW;
	}
	tree_difference = diff;
	if (tree_difference == REV_TREE_DIFFERENT)
		DIFF_OPT_SET(options, HAS_CHANGES);
}

static void file_change(struct diff_options *options,
		 unsigned old_mode, unsigned new_mode,
		 const unsigned char *old_sha1,
		 const unsigned char *new_sha1,
		 const char *fullpath)
{
	tree_difference = REV_TREE_DIFFERENT;
	DIFF_OPT_SET(options, HAS_CHANGES);
}

static int rev_compare_tree(struct rev_info *revs, struct tree *t1, struct tree *t2)
{
	if (!t1)
		return REV_TREE_NEW;
	if (!t2)
		return REV_TREE_DIFFERENT;
	tree_difference = REV_TREE_SAME;
	DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
	if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "",
			   &revs->pruning) < 0)
		return REV_TREE_DIFFERENT;
	return tree_difference;
}

static int rev_same_tree_as_empty(struct rev_info *revs, struct tree *t1)
{
	int retval;
	void *tree;
	unsigned long size;
	struct tree_desc empty, real;

	if (!t1)
		return 0;

	tree = read_object_with_reference(t1->object.sha1, tree_type, &size, NULL);
	if (!tree)
		return 0;
	init_tree_desc(&real, tree, size);
	init_tree_desc(&empty, "", 0);

	tree_difference = REV_TREE_SAME;
	DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
	retval = diff_tree(&empty, &real, "", &revs->pruning);
	free(tree);

	return retval >= 0 && (tree_difference == REV_TREE_SAME);
}

static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
{
	struct commit_list **pp, *parent;
	int tree_changed = 0, tree_same = 0;

	/*
	 * If we don't do pruning, everything is interesting
	 */
	if (!revs->prune)
		return;

	if (!commit->tree)
		return;

	if (!commit->parents) {
		if (rev_same_tree_as_empty(revs, commit->tree))
			commit->object.flags |= TREESAME;
		return;
	}

	/*
	 * Normal non-merge commit? If we don't want to make the
	 * history dense, we consider it always to be a change..
	 */
	if (!revs->dense && !commit->parents->next)
		return;

	pp = &commit->parents;
	while ((parent = *pp) != NULL) {
		struct commit *p = parent->item;

		if (parse_commit(p) < 0)
			die("cannot simplify commit %s (because of %s)",
			    sha1_to_hex(commit->object.sha1),
			    sha1_to_hex(p->object.sha1));
		switch (rev_compare_tree(revs, p->tree, commit->tree)) {
		case REV_TREE_SAME:
			tree_same = 1;
			if (!revs->simplify_history || (p->object.flags & UNINTERESTING)) {
				/* Even if a merge with an uninteresting
				 * side branch brought the entire change
				 * we are interested in, we do not want
				 * to lose the other branches of this
				 * merge, so we just keep going.
				 */
				pp = &parent->next;
				continue;
			}
			parent->next = NULL;
			commit->parents = parent;
			commit->object.flags |= TREESAME;
			return;

		case REV_TREE_NEW:
			if (revs->remove_empty_trees &&
			    rev_same_tree_as_empty(revs, p->tree)) {
				/* We are adding all the specified
				 * paths from this parent, so the
				 * history beyond this parent is not
				 * interesting.  Remove its parents
				 * (they are grandparents for us).
				 * IOW, we pretend this parent is a
				 * "root" commit.
				 */
				if (parse_commit(p) < 0)
					die("cannot simplify commit %s (invalid %s)",
					    sha1_to_hex(commit->object.sha1),
					    sha1_to_hex(p->object.sha1));
				p->parents = NULL;
			}
		/* fallthrough */
		case REV_TREE_DIFFERENT:
			tree_changed = 1;
			pp = &parent->next;
			continue;
		}
		die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
	}
	if (tree_changed && !tree_same)
		return;
	commit->object.flags |= TREESAME;
}

static void insert_by_date_cached(struct commit *p, struct commit_list **head,
		    struct commit_list *cached_base, struct commit_list **cache)
{
	struct commit_list *new_entry;

	if (cached_base && p->date < cached_base->item->date)
		new_entry = insert_by_date(p, &cached_base->next);
	else
		new_entry = insert_by_date(p, head);

	if (cache && (!*cache || p->date < (*cache)->item->date))
		*cache = new_entry;
}

static int add_parents_to_list(struct rev_info *revs, struct commit *commit,
		    struct commit_list **list, struct commit_list **cache_ptr)
{
	struct commit_list *parent = commit->parents;
	unsigned left_flag;
	struct commit_list *cached_base = cache_ptr ? *cache_ptr : NULL;

	if (commit->object.flags & ADDED)
		return 0;
	commit->object.flags |= ADDED;

	/*
	 * If the commit is uninteresting, don't try to
	 * prune parents - we want the maximal uninteresting
	 * set.
	 *
	 * Normally we haven't parsed the parent
	 * yet, so we won't have a parent of a parent
	 * here. However, it may turn out that we've
	 * reached this commit some other way (where it
	 * wasn't uninteresting), in which case we need
	 * to mark its parents recursively too..
	 */
	if (commit->object.flags & UNINTERESTING) {
		while (parent) {
			struct commit *p = parent->item;
			parent = parent->next;
			if (parse_commit(p) < 0)
				return -1;
			p->object.flags |= UNINTERESTING;
			if (p->parents)
				mark_parents_uninteresting(p);
			if (p->object.flags & SEEN)
				continue;
			p->object.flags |= SEEN;
			insert_by_date_cached(p, list, cached_base, cache_ptr);
		}
		return 0;
	}

	/*
	 * Ok, the commit wasn't uninteresting. Try to
	 * simplify the commit history and find the parent
	 * that has no differences in the path set if one exists.
	 */
	try_to_simplify_commit(revs, commit);

	if (revs->no_walk)
		return 0;

	left_flag = (commit->object.flags & SYMMETRIC_LEFT);

	for (parent = commit->parents; parent; parent = parent->next) {
		struct commit *p = parent->item;

		if (parse_commit(p) < 0)
			return -1;
		p->object.flags |= left_flag;
		if (!(p->object.flags & SEEN)) {
			p->object.flags |= SEEN;
			insert_by_date_cached(p, list, cached_base, cache_ptr);
		}
		if(revs->first_parent_only)
			break;
	}
	return 0;
}

static void cherry_pick_list(struct commit_list *list, struct rev_info *revs)
{
	struct commit_list *p;
	int left_count = 0, right_count = 0;
	int left_first;
	struct patch_ids ids;

	/* First count the commits on the left and on the right */
	for (p = list; p; p = p->next) {
		struct commit *commit = p->item;
		unsigned flags = commit->object.flags;
		if (flags & BOUNDARY)
			;
		else if (flags & SYMMETRIC_LEFT)
			left_count++;
		else
			right_count++;
	}

	left_first = left_count < right_count;
	init_patch_ids(&ids);
	if (revs->diffopt.nr_paths) {
		ids.diffopts.nr_paths = revs->diffopt.nr_paths;
		ids.diffopts.paths = revs->diffopt.paths;
		ids.diffopts.pathlens = revs->diffopt.pathlens;
	}

	/* Compute patch-ids for one side */
	for (p = list; p; p = p->next) {
		struct commit *commit = p->item;
		unsigned flags = commit->object.flags;

		if (flags & BOUNDARY)
			continue;
		/*
		 * If we have fewer left, left_first is set and we omit
		 * commits on the right branch in this loop.  If we have
		 * fewer right, we skip the left ones.
		 */
		if (left_first != !!(flags & SYMMETRIC_LEFT))
			continue;
		commit->util = add_commit_patch_id(commit, &ids);
	}

	/* Check the other side */
	for (p = list; p; p = p->next) {
		struct commit *commit = p->item;
		struct patch_id *id;
		unsigned flags = commit->object.flags;

		if (flags & BOUNDARY)
			continue;
		/*
		 * If we have fewer left, left_first is set and we omit
		 * commits on the left branch in this loop.
		 */
		if (left_first == !!(flags & SYMMETRIC_LEFT))
			continue;

		/*
		 * Have we seen the same patch id?
		 */
		id = has_commit_patch_id(commit, &ids);
		if (!id)
			continue;
		id->seen = 1;
		commit->object.flags |= SHOWN;
	}

	/* Now check the original side for seen ones */
	for (p = list; p; p = p->next) {
		struct commit *commit = p->item;
		struct patch_id *ent;

		ent = commit->util;
		if (!ent)
			continue;
		if (ent->seen)
			commit->object.flags |= SHOWN;
		commit->util = NULL;
	}

	free_patch_ids(&ids);
}

/* How many extra uninteresting commits we want to see.. */
#define SLOP 5

static int still_interesting(struct commit_list *src, unsigned long date, int slop)
{
	/*
	 * No source list at all? We're definitely done..
	 */
	if (!src)
		return 0;

	/*
	 * Does the destination list contain entries with a date
	 * before the source list? Definitely _not_ done.
	 */
	if (date < src->item->date)
		return SLOP;

	/*
	 * Does the source list still have interesting commits in
	 * it? Definitely not done..
	 */
	if (!everybody_uninteresting(src))
		return SLOP;

	/* Ok, we're closing in.. */
	return slop-1;
}

static int limit_list(struct rev_info *revs)
{
	int slop = SLOP;
	unsigned long date = ~0ul;
	struct commit_list *list = revs->commits;
	struct commit_list *newlist = NULL;
	struct commit_list **p = &newlist;

	while (list) {
		struct commit_list *entry = list;
		struct commit *commit = list->item;
		struct object *obj = &commit->object;
		show_early_output_fn_t show;

		list = list->next;
		free(entry);

		if (revs->max_age != -1 && (commit->date < revs->max_age))
			obj->flags |= UNINTERESTING;
		if (add_parents_to_list(revs, commit, &list, NULL) < 0)
			return -1;
		if (obj->flags & UNINTERESTING) {
			mark_parents_uninteresting(commit);
			if (revs->show_all)
				p = &commit_list_insert(commit, p)->next;
			slop = still_interesting(list, date, slop);
			if (slop)
				continue;
			/* If showing all, add the whole pending list to the end */
			if (revs->show_all)
				*p = list;
			break;
		}
		if (revs->min_age != -1 && (commit->date > revs->min_age))
			continue;
		date = commit->date;
		p = &commit_list_insert(commit, p)->next;

		show = show_early_output;
		if (!show)
			continue;

		show(revs, newlist);
		show_early_output = NULL;
	}
	if (revs->cherry_pick)
		cherry_pick_list(newlist, revs);

	revs->commits = newlist;
	return 0;
}

struct all_refs_cb {
	int all_flags;
	int warned_bad_reflog;
	struct rev_info *all_revs;
	const char *name_for_errormsg;
};

static int handle_one_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
{
	struct all_refs_cb *cb = cb_data;
	struct object *object = get_reference(cb->all_revs, path, sha1,
					      cb->all_flags);
	add_pending_object(cb->all_revs, object, path);
	return 0;
}

static void handle_refs(struct rev_info *revs, unsigned flags,
		int (*for_each)(each_ref_fn, void *))
{
	struct all_refs_cb cb;
	cb.all_revs = revs;
	cb.all_flags = flags;
	for_each(handle_one_ref, &cb);
}

static void handle_one_reflog_commit(unsigned char *sha1, void *cb_data)
{
	struct all_refs_cb *cb = cb_data;
	if (!is_null_sha1(sha1)) {
		struct object *o = parse_object(sha1);
		if (o) {
			o->flags |= cb->all_flags;
			add_pending_object(cb->all_revs, o, "");
		}
		else if (!cb->warned_bad_reflog) {
			warning("reflog of '%s' references pruned commits",
				cb->name_for_errormsg);
			cb->warned_bad_reflog = 1;
		}
	}
}

static int handle_one_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
		const char *email, unsigned long timestamp, int tz,
		const char *message, void *cb_data)
{
	handle_one_reflog_commit(osha1, cb_data);
	handle_one_reflog_commit(nsha1, cb_data);
	return 0;
}

static int handle_one_reflog(const char *path, const unsigned char *sha1, int flag, void *cb_data)
{
	struct all_refs_cb *cb = cb_data;
	cb->warned_bad_reflog = 0;
	cb->name_for_errormsg = path;
	for_each_reflog_ent(path, handle_one_reflog_ent, cb_data);
	return 0;
}

static void handle_reflog(struct rev_info *revs, unsigned flags)
{
	struct all_refs_cb cb;
	cb.all_revs = revs;
	cb.all_flags = flags;
	for_each_reflog(handle_one_reflog, &cb);
}

static int add_parents_only(struct rev_info *revs, const char *arg, int flags)
{
	unsigned char sha1[20];
	struct object *it;
	struct commit *commit;
	struct commit_list *parents;

	if (*arg == '^') {
		flags ^= UNINTERESTING;
		arg++;
	}
	if (get_sha1(arg, sha1))
		return 0;
	while (1) {
		it = get_reference(revs, arg, sha1, 0);
		if (it->type != OBJ_TAG)
			break;
		if (!((struct tag*)it)->tagged)
			return 0;
		hashcpy(sha1, ((struct tag*)it)->tagged->sha1);
	}
	if (it->type != OBJ_COMMIT)
		return 0;
	commit = (struct commit *)it;
	for (parents = commit->parents; parents; parents = parents->next) {
		it = &parents->item->object;
		it->flags |= flags;
		add_pending_object(revs, it, arg);
	}
	return 1;
}

void init_revisions(struct rev_info *revs, const char *prefix)
{
	memset(revs, 0, sizeof(*revs));

	revs->abbrev = DEFAULT_ABBREV;
	revs->ignore_merges = 1;
	revs->simplify_history = 1;
	DIFF_OPT_SET(&revs->pruning, RECURSIVE);
	DIFF_OPT_SET(&revs->pruning, QUIET);
	revs->pruning.add_remove = file_add_remove;
	revs->pruning.change = file_change;
	revs->lifo = 1;
	revs->dense = 1;
	revs->prefix = prefix;
	revs->max_age = -1;
	revs->min_age = -1;
	revs->skip_count = -1;
	revs->max_count = -1;

	revs->commit_format = CMIT_FMT_DEFAULT;

	revs->grep_filter.status_only = 1;
	revs->grep_filter.pattern_tail = &(revs->grep_filter.pattern_list);
	revs->grep_filter.regflags = REG_NEWLINE;

	diff_setup(&revs->diffopt);
	if (prefix && !revs->diffopt.prefix) {
		revs->diffopt.prefix = prefix;
		revs->diffopt.prefix_length = strlen(prefix);
	}
}

static void add_pending_commit_list(struct rev_info *revs,
                                    struct commit_list *commit_list,
                                    unsigned int flags)
{
	while (commit_list) {
		struct object *object = &commit_list->item->object;
		object->flags |= flags;
		add_pending_object(revs, object, sha1_to_hex(object->sha1));
		commit_list = commit_list->next;
	}
}

static void prepare_show_merge(struct rev_info *revs)
{
	struct commit_list *bases;
	struct commit *head, *other;
	unsigned char sha1[20];
	const char **prune = NULL;
	int i, prune_num = 1; /* counting terminating NULL */

	if (get_sha1("HEAD", sha1) || !(head = lookup_commit(sha1)))
		die("--merge without HEAD?");
	if (get_sha1("MERGE_HEAD", sha1) || !(other = lookup_commit(sha1)))
		die("--merge without MERGE_HEAD?");
	add_pending_object(revs, &head->object, "HEAD");
	add_pending_object(revs, &other->object, "MERGE_HEAD");
	bases = get_merge_bases(head, other, 1);
	add_pending_commit_list(revs, bases, UNINTERESTING);
	free_commit_list(bases);
	head->object.flags |= SYMMETRIC_LEFT;

	if (!active_nr)
		read_cache();
	for (i = 0; i < active_nr; i++) {
		struct cache_entry *ce = active_cache[i];
		if (!ce_stage(ce))
			continue;
		if (ce_path_match(ce, revs->prune_data)) {
			prune_num++;
			prune = xrealloc(prune, sizeof(*prune) * prune_num);
			prune[prune_num-2] = ce->name;
			prune[prune_num-1] = NULL;
		}
		while ((i+1 < active_nr) &&
		       ce_same_name(ce, active_cache[i+1]))
			i++;
	}
	revs->prune_data = prune;
	revs->limited = 1;
}

int handle_revision_arg(const char *arg, struct rev_info *revs,
			int flags,
			int cant_be_filename)
{
	unsigned mode;
	char *dotdot;
	struct object *object;
	unsigned char sha1[20];
	int local_flags;

	dotdot = strstr(arg, "..");
	if (dotdot) {
		unsigned char from_sha1[20];
		const char *next = dotdot + 2;
		const char *this = arg;
		int symmetric = *next == '.';
		unsigned int flags_exclude = flags ^ UNINTERESTING;

		*dotdot = 0;
		next += symmetric;

		if (!*next)
			next = "HEAD";
		if (dotdot == arg)
			this = "HEAD";
		if (!get_sha1(this, from_sha1) &&
		    !get_sha1(next, sha1)) {
			struct commit *a, *b;
			struct commit_list *exclude;

			a = lookup_commit_reference(from_sha1);
			b = lookup_commit_reference(sha1);
			if (!a || !b) {
				die(symmetric ?
				    "Invalid symmetric difference expression %s...%s" :
				    "Invalid revision range %s..%s",
				    arg, next);
			}

			if (!cant_be_filename) {
				*dotdot = '.';
				verify_non_filename(revs->prefix, arg);
			}

			if (symmetric) {
				exclude = get_merge_bases(a, b, 1);
				add_pending_commit_list(revs, exclude,
							flags_exclude);
				free_commit_list(exclude);
				a->object.flags |= flags | SYMMETRIC_LEFT;
			} else
				a->object.flags |= flags_exclude;
			b->object.flags |= flags;
			add_pending_object(revs, &a->object, this);
			add_pending_object(revs, &b->object, next);
			return 0;
		}
		*dotdot = '.';
	}
	dotdot = strstr(arg, "^@");
	if (dotdot && !dotdot[2]) {
		*dotdot = 0;
		if (add_parents_only(revs, arg, flags))
			return 0;
		*dotdot = '^';
	}
	dotdot = strstr(arg, "^!");
	if (dotdot && !dotdot[2]) {
		*dotdot = 0;
		if (!add_parents_only(revs, arg, flags ^ UNINTERESTING))
			*dotdot = '^';
	}

	local_flags = 0;
	if (*arg == '^') {
		local_flags = UNINTERESTING;
		arg++;
	}
	if (get_sha1_with_mode(arg, sha1, &mode))
		return -1;
	if (!cant_be_filename)
		verify_non_filename(revs->prefix, arg);
	object = get_reference(revs, arg, sha1, flags ^ local_flags);
	add_pending_object_with_mode(revs, object, arg, mode);
	return 0;
}

void read_revisions_from_stdin(struct rev_info *revs)
{
	char line[1000];

	while (fgets(line, sizeof(line), stdin) != NULL) {
		int len = strlen(line);
		if (len && line[len - 1] == '\n')
			line[--len] = '\0';
		if (!len)
			break;
		if (line[0] == '-')
			die("options not supported in --stdin mode");
		if (handle_revision_arg(line, revs, 0, 1))
			die("bad revision '%s'", line);
	}
}

static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
{
	append_grep_pattern(&revs->grep_filter, ptn, "command line", 0, what);
}

static void add_header_grep(struct rev_info *revs, enum grep_header_field field, const char *pattern)
{
	append_header_grep_pattern(&revs->grep_filter, field, pattern);
}

static void add_message_grep(struct rev_info *revs, const char *pattern)
{
	add_grep(revs, pattern, GREP_PATTERN_BODY);
}

static void add_ignore_packed(struct rev_info *revs, const char *name)
{
	int num = ++revs->num_ignore_packed;

	revs->ignore_packed = xrealloc(revs->ignore_packed,
				       sizeof(const char *) * (num + 1));
	revs->ignore_packed[num-1] = name;
	revs->ignore_packed[num] = NULL;
}

static int handle_revision_opt(struct rev_info *revs, int argc, const char **argv,
			       int *unkc, const char **unkv)
{
	const char *arg = argv[0];

	/* pseudo revision arguments */
	if (!strcmp(arg, "--all") || !strcmp(arg, "--branches") ||
	    !strcmp(arg, "--tags") || !strcmp(arg, "--remotes") ||
	    !strcmp(arg, "--reflog") || !strcmp(arg, "--not") ||
	    !strcmp(arg, "--no-walk") || !strcmp(arg, "--do-walk"))
	{
		unkv[(*unkc)++] = arg;
		return 1;
	}

	if (!prefixcmp(arg, "--max-count=")) {
		revs->max_count = atoi(arg + 12);
	} else if (!prefixcmp(arg, "--skip=")) {
		revs->skip_count = atoi(arg + 7);
	} else if ((*arg == '-') && isdigit(arg[1])) {
	/* accept -<digit>, like traditional "head" */
		revs->max_count = atoi(arg + 1);
	} else if (!strcmp(arg, "-n")) {
		if (argc <= 1)
			return error("-n requires an argument");
		revs->max_count = atoi(argv[1]);
		return 2;
	} else if (!prefixcmp(arg, "-n")) {
		revs->max_count = atoi(arg + 2);
	} else if (!prefixcmp(arg, "--max-age=")) {
		revs->max_age = atoi(arg + 10);
	} else if (!prefixcmp(arg, "--since=")) {
		revs->max_age = approxidate(arg + 8);
	} else if (!prefixcmp(arg, "--after=")) {
		revs->max_age = approxidate(arg + 8);
	} else if (!prefixcmp(arg, "--min-age=")) {
		revs->min_age = atoi(arg + 10);
	} else if (!prefixcmp(arg, "--before=")) {
		revs->min_age = approxidate(arg + 9);
	} else if (!prefixcmp(arg, "--until=")) {
		revs->min_age = approxidate(arg + 8);
	} else if (!strcmp(arg, "--first-parent")) {
		revs->first_parent_only = 1;
	} else if (!strcmp(arg, "-g") || !strcmp(arg, "--walk-reflogs")) {
		init_reflog_walk(&revs->reflog_info);
	} else if (!strcmp(arg, "--default")) {
		if (argc <= 1)
			return error("bad --default argument");
		revs->def = argv[1];
		return 2;
	} else if (!strcmp(arg, "--merge")) {
		revs->show_merge = 1;
	} else if (!strcmp(arg, "--topo-order")) {
		revs->lifo = 1;
		revs->topo_order = 1;
	} else if (!strcmp(arg, "--date-order")) {
		revs->lifo = 0;
		revs->topo_order = 1;
	} else if (!prefixcmp(arg, "--early-output")) {
		int count = 100;
		switch (arg[14]) {
		case '=':
			count = atoi(arg+15);
			/* Fallthrough */
		case 0:
			revs->topo_order = 1;
		       revs->early_output = count;
		}
	} else if (!strcmp(arg, "--parents")) {
		revs->rewrite_parents = 1;
		revs->print_parents = 1;
	} else if (!strcmp(arg, "--dense")) {
		revs->dense = 1;
	} else if (!strcmp(arg, "--sparse")) {
		revs->dense = 0;
	} else if (!strcmp(arg, "--show-all")) {
		revs->show_all = 1;
	} else if (!strcmp(arg, "--remove-empty")) {
		revs->remove_empty_trees = 1;
	} else if (!strcmp(arg, "--no-merges")) {
		revs->no_merges = 1;
	} else if (!strcmp(arg, "--boundary")) {
		revs->boundary = 1;
	} else if (!strcmp(arg, "--left-right")) {
		revs->left_right = 1;
	} else if (!strcmp(arg, "--cherry-pick")) {
		revs->cherry_pick = 1;
		revs->limited = 1;
	} else if (!strcmp(arg, "--objects")) {
		revs->tag_objects = 1;
		revs->tree_objects = 1;
		revs->blob_objects = 1;
	} else if (!strcmp(arg, "--objects-edge")) {
		revs->tag_objects = 1;
		revs->tree_objects = 1;
		revs->blob_objects = 1;
		revs->edge_hint = 1;
	} else if (!strcmp(arg, "--unpacked")) {
		revs->unpacked = 1;
		free(revs->ignore_packed);
		revs->ignore_packed = NULL;
		revs->num_ignore_packed = 0;
	} else if (!prefixcmp(arg, "--unpacked=")) {
		revs->unpacked = 1;
		add_ignore_packed(revs, arg+11);
	} else if (!strcmp(arg, "-r")) {
		revs->diff = 1;
		DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
	} else if (!strcmp(arg, "-t")) {
		revs->diff = 1;
		DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
		DIFF_OPT_SET(&revs->diffopt, TREE_IN_RECURSIVE);
	} else if (!strcmp(arg, "-m")) {
		revs->ignore_merges = 0;
	} else if (!strcmp(arg, "-c")) {
		revs->diff = 1;
		revs->dense_combined_merges = 0;
		revs->combine_merges = 1;
	} else if (!strcmp(arg, "--cc")) {
		revs->diff = 1;
		revs->dense_combined_merges = 1;
		revs->combine_merges = 1;
	} else if (!strcmp(arg, "-v")) {
		revs->verbose_header = 1;
	} else if (!strcmp(arg, "--pretty")) {
		revs->verbose_header = 1;
		get_commit_format(arg+8, revs);
	} else if (!prefixcmp(arg, "--pretty=")) {
		revs->verbose_header = 1;
		get_commit_format(arg+9, revs);
	} else if (!strcmp(arg, "--graph")) {
		revs->topo_order = 1;
		revs->rewrite_parents = 1;
		revs->graph = graph_init(revs);
	} else if (!strcmp(arg, "--root")) {
		revs->show_root_diff = 1;
	} else if (!strcmp(arg, "--no-commit-id")) {
		revs->no_commit_id = 1;
	} else if (!strcmp(arg, "--always")) {
		revs->always_show_header = 1;
	} else if (!strcmp(arg, "--no-abbrev")) {
		revs->abbrev = 0;
	} else if (!strcmp(arg, "--abbrev")) {
		revs->abbrev = DEFAULT_ABBREV;
	} else if (!prefixcmp(arg, "--abbrev=")) {
		revs->abbrev = strtoul(arg + 9, NULL, 10);
		if (revs->abbrev < MINIMUM_ABBREV)
			revs->abbrev = MINIMUM_ABBREV;
		else if (revs->abbrev > 40)
			revs->abbrev = 40;
	} else if (!strcmp(arg, "--abbrev-commit")) {
		revs->abbrev_commit = 1;
	} else if (!strcmp(arg, "--full-diff")) {
		revs->diff = 1;
		revs->full_diff = 1;
	} else if (!strcmp(arg, "--full-history")) {
		revs->simplify_history = 0;
	} else if (!strcmp(arg, "--relative-date")) {
		revs->date_mode = DATE_RELATIVE;
	} else if (!strncmp(arg, "--date=", 7)) {
		revs->date_mode = parse_date_format(arg + 7);
	} else if (!strcmp(arg, "--log-size")) {
		revs->show_log_size = 1;
	}
	/*
	 * Grepping the commit log
	 */
	else if (!prefixcmp(arg, "--author=")) {
		add_header_grep(revs, GREP_HEADER_AUTHOR, arg+9);
	} else if (!prefixcmp(arg, "--committer=")) {
		add_header_grep(revs, GREP_HEADER_COMMITTER, arg+12);
	} else if (!prefixcmp(arg, "--grep=")) {
		add_message_grep(revs, arg+7);
	} else if (!strcmp(arg, "--extended-regexp") || !strcmp(arg, "-E")) {
		revs->grep_filter.regflags |= REG_EXTENDED;
	} else if (!strcmp(arg, "--regexp-ignore-case") || !strcmp(arg, "-i")) {
		revs->grep_filter.regflags |= REG_ICASE;
	} else if (!strcmp(arg, "--fixed-strings") || !strcmp(arg, "-F")) {
		revs->grep_filter.fixed = 1;
	} else if (!strcmp(arg, "--all-match")) {
		revs->grep_filter.all_match = 1;
	} else if (!prefixcmp(arg, "--encoding=")) {
		arg += 11;
		if (strcmp(arg, "none"))
			git_log_output_encoding = xstrdup(arg);
		else
			git_log_output_encoding = "";
	} else if (!strcmp(arg, "--reverse")) {
		revs->reverse ^= 1;
	} else if (!strcmp(arg, "--children")) {
		revs->children.name = "children";
		revs->limited = 1;
	} else {
		int opts = diff_opt_parse(&revs->diffopt, argv, argc);
		if (!opts)
			unkv[(*unkc)++] = arg;
		return opts;
	}

	return 1;
}

void parse_revision_opt(struct rev_info *revs, struct parse_opt_ctx_t *ctx,
			const struct option *options,
			const char * const usagestr[])
{
	int n = handle_revision_opt(revs, ctx->argc, ctx->argv,
				    &ctx->cpidx, ctx->out);
	if (n <= 0) {
		error("unknown option `%s'", ctx->argv[0]);
		usage_with_options(usagestr, options);
	}
	ctx->argv += n;
	ctx->argc -= n;
}

/*
 * Parse revision information, filling in the "rev_info" structure,
 * and removing the used arguments from the argument list.
 *
 * Returns the number of arguments left that weren't recognized
 * (which are also moved to the head of the argument list)
 */
int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def)
{
	int i, flags, left, seen_dashdash;

	/* First, search for "--" */
	seen_dashdash = 0;
	for (i = 1; i < argc; i++) {
		const char *arg = argv[i];
		if (strcmp(arg, "--"))
			continue;
		argv[i] = NULL;
		argc = i;
		if (argv[i + 1])
			revs->prune_data = get_pathspec(revs->prefix, argv + i + 1);
		seen_dashdash = 1;
		break;
	}

	/* Second, deal with arguments and options */
	flags = 0;
	for (left = i = 1; i < argc; i++) {
		const char *arg = argv[i];
		if (*arg == '-') {
			int opts;

			if (!strcmp(arg, "--all")) {
				handle_refs(revs, flags, for_each_ref);
				continue;
			}
			if (!strcmp(arg, "--branches")) {
				handle_refs(revs, flags, for_each_branch_ref);
				continue;
			}
			if (!strcmp(arg, "--tags")) {
				handle_refs(revs, flags, for_each_tag_ref);
				continue;
			}
			if (!strcmp(arg, "--remotes")) {
				handle_refs(revs, flags, for_each_remote_ref);
				continue;
			}
			if (!strcmp(arg, "--reflog")) {
				handle_reflog(revs, flags);
				continue;
			}
			if (!strcmp(arg, "--not")) {
				flags ^= UNINTERESTING;
				continue;
			}
			if (!strcmp(arg, "--no-walk")) {
				revs->no_walk = 1;
				continue;
			}
			if (!strcmp(arg, "--do-walk")) {
				revs->no_walk = 0;
				continue;
			}

			opts = handle_revision_opt(revs, argc - i, argv + i, &left, argv);
			if (opts > 0) {
				i += opts - 1;
				continue;
			}
			if (opts < 0)
				exit(128);
			continue;
		}

		if (handle_revision_arg(arg, revs, flags, seen_dashdash)) {
			int j;
			if (seen_dashdash || *arg == '^')
				die("bad revision '%s'", arg);

			/* If we didn't have a "--":
			 * (1) all filenames must exist;
			 * (2) all rev-args must not be interpretable
			 *     as a valid filename.
			 * but the latter we have checked in the main loop.
			 */
			for (j = i; j < argc; j++)
				verify_filename(revs->prefix, argv[j]);

			revs->prune_data = get_pathspec(revs->prefix,
							argv + i);
			break;
		}
	}

	if (revs->def == NULL)
		revs->def = def;
	if (revs->show_merge)
		prepare_show_merge(revs);
	if (revs->def && !revs->pending.nr) {
		unsigned char sha1[20];
		struct object *object;
		unsigned mode;
		if (get_sha1_with_mode(revs->def, sha1, &mode))
			die("bad default revision '%s'", revs->def);
		object = get_reference(revs, revs->def, sha1, 0);
		add_pending_object_with_mode(revs, object, revs->def, mode);
	}

	/* Did the user ask for any diff output? Run the diff! */
	if (revs->diffopt.output_format & ~DIFF_FORMAT_NO_OUTPUT)
		revs->diff = 1;

	/* Pickaxe, diff-filter and rename following need diffs */
	if (revs->diffopt.pickaxe ||
	    revs->diffopt.filter ||
	    DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
		revs->diff = 1;

	if (revs->topo_order)
		revs->limited = 1;

	if (revs->prune_data) {
		diff_tree_setup_paths(revs->prune_data, &revs->pruning);
		/* Can't prune commits with rename following: the paths change.. */
		if (!DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
			revs->prune = 1;
		if (!revs->full_diff)
			diff_tree_setup_paths(revs->prune_data, &revs->diffopt);
	}
	if (revs->combine_merges) {
		revs->ignore_merges = 0;
		if (revs->dense_combined_merges && !revs->diffopt.output_format)
			revs->diffopt.output_format = DIFF_FORMAT_PATCH;
	}
	revs->diffopt.abbrev = revs->abbrev;
	if (diff_setup_done(&revs->diffopt) < 0)
		die("diff_setup_done failed");

	compile_grep_patterns(&revs->grep_filter);

	if (revs->reverse && revs->reflog_info)
		die("cannot combine --reverse with --walk-reflogs");
	if (revs->rewrite_parents && revs->children.name)
		die("cannot combine --parents and --children");

	/*
	 * Limitations on the graph functionality
	 */
	if (revs->reverse && revs->graph)
		die("cannot combine --reverse with --graph");

	if (revs->reflog_info && revs->graph)
		die("cannot combine --walk-reflogs with --graph");

	return left;
}

static void add_child(struct rev_info *revs, struct commit *parent, struct commit *child)
{
	struct commit_list *l = xcalloc(1, sizeof(*l));

	l->item = child;
	l->next = add_decoration(&revs->children, &parent->object, l);
}

static void set_children(struct rev_info *revs)
{
	struct commit_list *l;
	for (l = revs->commits; l; l = l->next) {
		struct commit *commit = l->item;
		struct commit_list *p;

		for (p = commit->parents; p; p = p->next)
			add_child(revs, p->item, commit);
	}
}

int prepare_revision_walk(struct rev_info *revs)
{
	int nr = revs->pending.nr;
	struct object_array_entry *e, *list;

	e = list = revs->pending.objects;
	revs->pending.nr = 0;
	revs->pending.alloc = 0;
	revs->pending.objects = NULL;
	while (--nr >= 0) {
		struct commit *commit = handle_commit(revs, e->item, e->name);
		if (commit) {
			if (!(commit->object.flags & SEEN)) {
				commit->object.flags |= SEEN;
				insert_by_date(commit, &revs->commits);
			}
		}
		e++;
	}
	free(list);

	if (revs->no_walk)
		return 0;
	if (revs->limited)
		if (limit_list(revs) < 0)
			return -1;
	if (revs->topo_order)
		sort_in_topological_order(&revs->commits, revs->lifo);
	if (revs->children.name)
		set_children(revs);
	return 0;
}

enum rewrite_result {
	rewrite_one_ok,
	rewrite_one_noparents,
	rewrite_one_error,
};

static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp)
{
	struct commit_list *cache = NULL;

	for (;;) {
		struct commit *p = *pp;
		if (!revs->limited)
			if (add_parents_to_list(revs, p, &revs->commits, &cache) < 0)
				return rewrite_one_error;
		if (p->parents && p->parents->next)
			return rewrite_one_ok;
		if (p->object.flags & UNINTERESTING)
			return rewrite_one_ok;
		if (!(p->object.flags & TREESAME))
			return rewrite_one_ok;
		if (!p->parents)
			return rewrite_one_noparents;
		*pp = p->parents->item;
	}
}

static void remove_duplicate_parents(struct commit *commit)
{
	struct commit_list **pp, *p;

	/* Examine existing parents while marking ones we have seen... */
	pp = &commit->parents;
	while ((p = *pp) != NULL) {
		struct commit *parent = p->item;
		if (parent->object.flags & TMP_MARK) {
			*pp = p->next;
			continue;
		}
		parent->object.flags |= TMP_MARK;
		pp = &p->next;
	}
	/* ... and clear the temporary mark */
	for (p = commit->parents; p; p = p->next)
		p->item->object.flags &= ~TMP_MARK;
}

static int rewrite_parents(struct rev_info *revs, struct commit *commit)
{
	struct commit_list **pp = &commit->parents;
	while (*pp) {
		struct commit_list *parent = *pp;
		switch (rewrite_one(revs, &parent->item)) {
		case rewrite_one_ok:
			break;
		case rewrite_one_noparents:
			*pp = parent->next;
			continue;
		case rewrite_one_error:
			return -1;
		}
		pp = &parent->next;
	}
	remove_duplicate_parents(commit);
	return 0;
}

static int commit_match(struct commit *commit, struct rev_info *opt)
{
	if (!opt->grep_filter.pattern_list)
		return 1;
	return grep_buffer(&opt->grep_filter,
			   NULL, /* we say nothing, not even filename */
			   commit->buffer, strlen(commit->buffer));
}

static inline int want_ancestry(struct rev_info *revs)
{
	return (revs->rewrite_parents || revs->children.name);
}

enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
{
	if (commit->object.flags & SHOWN)
		return commit_ignore;
	if (revs->unpacked && has_sha1_pack(commit->object.sha1, revs->ignore_packed))
		return commit_ignore;
	if (revs->show_all)
		return commit_show;
	if (commit->object.flags & UNINTERESTING)
		return commit_ignore;
	if (revs->min_age != -1 && (commit->date > revs->min_age))
		return commit_ignore;
	if (revs->no_merges && commit->parents && commit->parents->next)
		return commit_ignore;
	if (!commit_match(commit, revs))
		return commit_ignore;
	if (revs->prune && revs->dense) {
		/* Commit without changes? */
		if (commit->object.flags & TREESAME) {
			/* drop merges unless we want parenthood */
			if (!want_ancestry(revs))
				return commit_ignore;
			/* non-merge - always ignore it */
			if (!commit->parents || !commit->parents->next)
				return commit_ignore;
		}
		if (want_ancestry(revs) && rewrite_parents(revs, commit) < 0)
			return commit_error;
	}
	return commit_show;
}

static struct commit *get_revision_1(struct rev_info *revs)
{
	if (!revs->commits)
		return NULL;

	do {
		struct commit_list *entry = revs->commits;
		struct commit *commit = entry->item;

		revs->commits = entry->next;
		free(entry);

		if (revs->reflog_info)
			fake_reflog_parent(revs->reflog_info, commit);

		/*
		 * If we haven't done the list limiting, we need to look at
		 * the parents here. We also need to do the date-based limiting
		 * that we'd otherwise have done in limit_list().
		 */
		if (!revs->limited) {
			if (revs->max_age != -1 &&
			    (commit->date < revs->max_age))
				continue;
			if (add_parents_to_list(revs, commit, &revs->commits, NULL) < 0)
				die("Failed to traverse parents of commit %s",
				    sha1_to_hex(commit->object.sha1));
		}

		switch (simplify_commit(revs, commit)) {
		case commit_ignore:
			continue;
		case commit_error:
			die("Failed to simplify parents of commit %s",
			    sha1_to_hex(commit->object.sha1));
		default:
			return commit;
		}
	} while (revs->commits);
	return NULL;
}

static void gc_boundary(struct object_array *array)
{
	unsigned nr = array->nr;
	unsigned alloc = array->alloc;
	struct object_array_entry *objects = array->objects;

	if (alloc <= nr) {
		unsigned i, j;
		for (i = j = 0; i < nr; i++) {
			if (objects[i].item->flags & SHOWN)
				continue;
			if (i != j)
				objects[j] = objects[i];
			j++;
		}
		for (i = j; i < nr; i++)
			objects[i].item = NULL;
		array->nr = j;
	}
}

static void create_boundary_commit_list(struct rev_info *revs)
{
	unsigned i;
	struct commit *c;
	struct object_array *array = &revs->boundary_commits;
	struct object_array_entry *objects = array->objects;

	/*
	 * If revs->commits is non-NULL at this point, an error occurred in
	 * get_revision_1().  Ignore the error and continue printing the
	 * boundary commits anyway.  (This is what the code has always
	 * done.)
	 */
	if (revs->commits) {
		free_commit_list(revs->commits);
		revs->commits = NULL;
	}

	/*
	 * Put all of the actual boundary commits from revs->boundary_commits
	 * into revs->commits
	 */
	for (i = 0; i < array->nr; i++) {
		c = (struct commit *)(objects[i].item);
		if (!c)
			continue;
		if (!(c->object.flags & CHILD_SHOWN))
			continue;
		if (c->object.flags & (SHOWN | BOUNDARY))
			continue;
		c->object.flags |= BOUNDARY;
		commit_list_insert(c, &revs->commits);
	}

	/*
	 * If revs->topo_order is set, sort the boundary commits
	 * in topological order
	 */
	sort_in_topological_order(&revs->commits, revs->lifo);
}

static struct commit *get_revision_internal(struct rev_info *revs)
{
	struct commit *c = NULL;
	struct commit_list *l;

	if (revs->boundary == 2) {
		/*
		 * All of the normal commits have already been returned,
		 * and we are now returning boundary commits.
		 * create_boundary_commit_list() has populated
		 * revs->commits with the remaining commits to return.
		 */
		c = pop_commit(&revs->commits);
		if (c)
			c->object.flags |= SHOWN;
		return c;
	}

	if (revs->reverse) {
		int limit = -1;

		if (0 <= revs->max_count) {
			limit = revs->max_count;
			if (0 < revs->skip_count)
				limit += revs->skip_count;
		}
		l = NULL;
		while ((c = get_revision_1(revs))) {
			commit_list_insert(c, &l);
			if ((0 < limit) && !--limit)
				break;
		}
		revs->commits = l;
		revs->reverse = 0;
		revs->max_count = -1;
		c = NULL;
	}

	/*
	 * Now pick up what they want to give us
	 */
	c = get_revision_1(revs);
	if (c) {
		while (0 < revs->skip_count) {
			revs->skip_count--;
			c = get_revision_1(revs);
			if (!c)
				break;
		}
	}

	/*
	 * Check the max_count.
	 */
	switch (revs->max_count) {
	case -1:
		break;
	case 0:
		c = NULL;
		break;
	default:
		revs->max_count--;
	}

	if (c)
		c->object.flags |= SHOWN;

	if (!revs->boundary) {
		return c;
	}

	if (!c) {
		/*
		 * get_revision_1() runs out the commits, and
		 * we are done computing the boundaries.
		 * switch to boundary commits output mode.
		 */
		revs->boundary = 2;

		/*
		 * Update revs->commits to contain the list of
		 * boundary commits.
		 */
		create_boundary_commit_list(revs);

		return get_revision_internal(revs);
	}

	/*
	 * boundary commits are the commits that are parents of the
	 * ones we got from get_revision_1() but they themselves are
	 * not returned from get_revision_1().  Before returning
	 * 'c', we need to mark its parents that they could be boundaries.
	 */

	for (l = c->parents; l; l = l->next) {
		struct object *p;
		p = &(l->item->object);
		if (p->flags & (CHILD_SHOWN | SHOWN))
			continue;
		p->flags |= CHILD_SHOWN;
		gc_boundary(&revs->boundary_commits);
		add_object_array(p, NULL, &revs->boundary_commits);
	}

	return c;
}

struct commit *get_revision(struct rev_info *revs)
{
	struct commit *c = get_revision_internal(revs);
	if (c && revs->graph)
		graph_update(revs->graph, c);
	return c;
}
Tip: Filter by directory path e.g. /media app.js to search for public/media/app.js.
Tip: Use camelCasing e.g. ProjME to search for ProjectModifiedEvent.java.
Tip: Filter by extension type e.g. /repo .js to search for all .js files in the /repo directory.
Tip: Separate your search with spaces e.g. /ssh pom.xml to search for src/ssh/pom.xml.
Tip: Use ↑ and ↓ arrow keys to navigate and return to view the file.
Tip: You can also navigate files with Ctrl+j (next) and Ctrl+k (previous) and view the file with Ctrl+o.
Tip: You can also navigate files with Alt+j (next) and Alt+k (previous) and view the file with Alt+o.