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
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948

/* pngset.c - storage of image information into info struct
 *
 * Copyright (c) 2018 Cosmin Truta
 * Copyright (c) 1998-2018 Glenn Randers-Pehrson
 * Copyright (c) 1996-1997 Andreas Dilger
 * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
 * and license in png.h
 *
 * The functions here are used during reads to store data from the file
 * into the info struct, and during writes to store application data
 * into the info struct for writing into the file.  This abstracts the
 * info struct and allows us to change the structure in the future.
 */

#include "pngpriv.h"

#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)

#ifdef PNG_bKGD_SUPPORTED
void PNGAPI
png_set_bKGD(png_const_structrp png_ptr, png_inforp info_ptr,
    png_const_color_16p background)
{
   png_debug1(1, "in %s storage function", "bKGD");

   if (png_ptr == NULL || info_ptr == NULL || background == NULL)
      return;

   info_ptr->background = *background;
   info_ptr->valid |= PNG_INFO_bKGD;
}
#endif

#ifdef PNG_cHRM_SUPPORTED
void PNGFAPI
png_set_cHRM_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
    png_fixed_point white_x, png_fixed_point white_y, png_fixed_point red_x,
    png_fixed_point red_y, png_fixed_point green_x, png_fixed_point green_y,
    png_fixed_point blue_x, png_fixed_point blue_y)
{
   png_xy xy;

   png_debug1(1, "in %s storage function", "cHRM fixed");

   if (png_ptr == NULL || info_ptr == NULL)
      return;

   xy.redx = red_x;
   xy.redy = red_y;
   xy.greenx = green_x;
   xy.greeny = green_y;
   xy.bluex = blue_x;
   xy.bluey = blue_y;
   xy.whitex = white_x;
   xy.whitey = white_y;

   if (png_colorspace_set_chromaticities(png_ptr, &info_ptr->colorspace, &xy,
       2/* override with app values*/) != 0)
      info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_cHRM;

   png_colorspace_sync_info(png_ptr, info_ptr);
}

void PNGFAPI
png_set_cHRM_XYZ_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
    png_fixed_point int_red_X, png_fixed_point int_red_Y,
    png_fixed_point int_red_Z, png_fixed_point int_green_X,
    png_fixed_point int_green_Y, png_fixed_point int_green_Z,
    png_fixed_point int_blue_X, png_fixed_point int_blue_Y,
    png_fixed_point int_blue_Z)
{
   png_XYZ XYZ;

   png_debug1(1, "in %s storage function", "cHRM XYZ fixed");

   if (png_ptr == NULL || info_ptr == NULL)
      return;

   XYZ.red_X = int_red_X;
   XYZ.red_Y = int_red_Y;
   XYZ.red_Z = int_red_Z;
   XYZ.green_X = int_green_X;
   XYZ.green_Y = int_green_Y;
   XYZ.green_Z = int_green_Z;
   XYZ.blue_X = int_blue_X;
   XYZ.blue_Y = int_blue_Y;
   XYZ.blue_Z = int_blue_Z;

   if (png_colorspace_set_endpoints(png_ptr, &info_ptr->colorspace,
       &XYZ, 2) != 0)
      info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_cHRM;

   png_colorspace_sync_info(png_ptr, info_ptr);
}

#  ifdef PNG_FLOATING_POINT_SUPPORTED
void PNGAPI
png_set_cHRM(png_const_structrp png_ptr, png_inforp info_ptr,
    double white_x, double white_y, double red_x, double red_y,
    double green_x, double green_y, double blue_x, double blue_y)
{
   png_set_cHRM_fixed(png_ptr, info_ptr,
       png_fixed(png_ptr, white_x, "cHRM White X"),
       png_fixed(png_ptr, white_y, "cHRM White Y"),
       png_fixed(png_ptr, red_x, "cHRM Red X"),
       png_fixed(png_ptr, red_y, "cHRM Red Y"),
       png_fixed(png_ptr, green_x, "cHRM Green X"),
       png_fixed(png_ptr, green_y, "cHRM Green Y"),
       png_fixed(png_ptr, blue_x, "cHRM Blue X"),
       png_fixed(png_ptr, blue_y, "cHRM Blue Y"));
}

void PNGAPI
png_set_cHRM_XYZ(png_const_structrp png_ptr, png_inforp info_ptr, double red_X,
    double red_Y, double red_Z, double green_X, double green_Y, double green_Z,
    double blue_X, double blue_Y, double blue_Z)
{
   png_set_cHRM_XYZ_fixed(png_ptr, info_ptr,
       png_fixed(png_ptr, red_X, "cHRM Red X"),
       png_fixed(png_ptr, red_Y, "cHRM Red Y"),
       png_fixed(png_ptr, red_Z, "cHRM Red Z"),
       png_fixed(png_ptr, green_X, "cHRM Green X"),
       png_fixed(png_ptr, green_Y, "cHRM Green Y"),
       png_fixed(png_ptr, green_Z, "cHRM Green Z"),
       png_fixed(png_ptr, blue_X, "cHRM Blue X"),
       png_fixed(png_ptr, blue_Y, "cHRM Blue Y"),
       png_fixed(png_ptr, blue_Z, "cHRM Blue Z"));
}
#  endif /* FLOATING_POINT */

#endif /* cHRM */

#ifdef PNG_eXIf_SUPPORTED
void PNGAPI
png_set_eXIf(png_const_structrp png_ptr, png_inforp info_ptr,
    png_bytep eXIf_buf)
{
  png_warning(png_ptr, "png_set_eXIf does not work; use png_set_eXIf_1");
  PNG_UNUSED(info_ptr)
  PNG_UNUSED(eXIf_buf)
}

void PNGAPI
png_set_eXIf_1(png_const_structrp png_ptr, png_inforp info_ptr,
    png_uint_32 num_exif, png_bytep eXIf_buf)
{
   int i;

   png_debug1(1, "in %s storage function", "eXIf");

   if (png_ptr == NULL || info_ptr == NULL)
      return;

   if (info_ptr->exif)
   {
      png_free(png_ptr, info_ptr->exif);
      info_ptr->exif = NULL;
   }

   info_ptr->num_exif = num_exif;

   info_ptr->exif = png_voidcast(png_bytep, png_malloc_warn(png_ptr,
       info_ptr->num_exif));

   if (info_ptr->exif == NULL)
   {
      png_warning(png_ptr, "Insufficient memory for eXIf chunk data");
      return;
   }

   info_ptr->free_me |= PNG_FREE_EXIF;

   for (i = 0; i < (int) info_ptr->num_exif; i++)
      info_ptr->exif[i] = eXIf_buf[i];

   info_ptr->valid |= PNG_INFO_eXIf;
}
#endif /* eXIf */

#ifdef PNG_gAMA_SUPPORTED
void PNGFAPI
png_set_gAMA_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
    png_fixed_point file_gamma)
{
   png_debug1(1, "in %s storage function", "gAMA");

   if (png_ptr == NULL || info_ptr == NULL)
      return;

   png_colorspace_set_gamma(png_ptr, &info_ptr->colorspace, file_gamma);
   png_colorspace_sync_info(png_ptr, info_ptr);
}

#  ifdef PNG_FLOATING_POINT_SUPPORTED
void PNGAPI
png_set_gAMA(png_const_structrp png_ptr, png_inforp info_ptr, double file_gamma)
{
   png_set_gAMA_fixed(png_ptr, info_ptr, png_fixed(png_ptr, file_gamma,
       "png_set_gAMA"));
}
#  endif
#endif

#ifdef PNG_hIST_SUPPORTED
void PNGAPI
png_set_hIST(png_const_structrp png_ptr, png_inforp info_ptr,
    png_const_uint_16p hist)
{
   int i;

   png_debug1(1, "in %s storage function", "hIST");

   if (png_ptr == NULL || info_ptr == NULL)
      return;

   if (info_ptr->num_palette == 0 || info_ptr->num_palette
       > PNG_MAX_PALETTE_LENGTH)
   {
      png_warning(png_ptr,
          "Invalid palette size, hIST allocation skipped");

      return;
   }

   png_free_data(png_ptr, info_ptr, PNG_FREE_HIST, 0);

   /* Changed from info->num_palette to PNG_MAX_PALETTE_LENGTH in
    * version 1.2.1
    */
   info_ptr->hist = png_voidcast(png_uint_16p, png_malloc_warn(png_ptr,
       PNG_MAX_PALETTE_LENGTH * (sizeof (png_uint_16))));

   if (info_ptr->hist == NULL)
   {
      png_warning(png_ptr, "Insufficient memory for hIST chunk data");

      return;
   }

   info_ptr->free_me |= PNG_FREE_HIST;

   for (i = 0; i < info_ptr->num_palette; i++)
      info_ptr->hist[i] = hist[i];

   info_ptr->valid |= PNG_INFO_hIST;
}
#endif

void PNGAPI
png_set_IHDR(png_const_structrp png_ptr, png_inforp info_ptr,
    png_uint_32 width, png_uint_32 height, int bit_depth,
    int color_type, int interlace_type, int compression_type,
    int filter_type)
{
   png_debug1(1, "in %s storage function", "IHDR");

   if (png_ptr == NULL || info_ptr == NULL)
      return;

   info_ptr->width = width;
   info_ptr->height = height;
   info_ptr->bit_depth = (png_byte)bit_depth;
   info_ptr->color_type = (png_byte)color_type;
   info_ptr->compression_type = (png_byte)compression_type;
   info_ptr->filter_type = (png_byte)filter_type;
   info_ptr->interlace_type = (png_byte)interlace_type;

   png_check_IHDR (png_ptr, info_ptr->width, info_ptr->height,
       info_ptr->bit_depth, info_ptr->color_type, info_ptr->interlace_type,
       info_ptr->compression_type, info_ptr->filter_type);

   if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
      info_ptr->channels = 1;

   else if ((info_ptr->color_type & PNG_COLOR_MASK_COLOR) != 0)
      info_ptr->channels = 3;

   else
      info_ptr->channels = 1;

   if ((info_ptr->color_type & PNG_COLOR_MASK_ALPHA) != 0)
      info_ptr->channels++;

   info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);

   info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, width);

#ifdef PNG_APNG_SUPPORTED
   /* for non-animated png. this may be overwritten from an acTL chunk later */
   info_ptr->num_frames = 1;
#endif
}

#ifdef PNG_oFFs_SUPPORTED
void PNGAPI
png_set_oFFs(png_const_structrp png_ptr, png_inforp info_ptr,
    png_int_32 offset_x, png_int_32 offset_y, int unit_type)
{
   png_debug1(1, "in %s storage function", "oFFs");

   if (png_ptr == NULL || info_ptr == NULL)
      return;

   info_ptr->x_offset = offset_x;
   info_ptr->y_offset = offset_y;
   info_ptr->offset_unit_type = (png_byte)unit_type;
   info_ptr->valid |= PNG_INFO_oFFs;
}
#endif

#ifdef PNG_pCAL_SUPPORTED
void PNGAPI
png_set_pCAL(png_const_structrp png_ptr, png_inforp info_ptr,
    png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type,
    int nparams, png_const_charp units, png_charpp params)
{
   size_t length;
   int i;

   png_debug1(1, "in %s storage function", "pCAL");

   if (png_ptr == NULL || info_ptr == NULL || purpose == NULL || units == NULL
       || (nparams > 0 && params == NULL))
      return;

   length = strlen(purpose) + 1;
   png_debug1(3, "allocating purpose for info (%lu bytes)",
       (unsigned long)length);

   /* TODO: validate format of calibration name and unit name */

   /* Check that the type matches the specification. */
   if (type < 0 || type > 3)
   {
      png_chunk_report(png_ptr, "Invalid pCAL equation type",
            PNG_CHUNK_WRITE_ERROR);
      return;
   }

   if (nparams < 0 || nparams > 255)
   {
      png_chunk_report(png_ptr, "Invalid pCAL parameter count",
            PNG_CHUNK_WRITE_ERROR);
      return;
   }

   /* Validate params[nparams] */
   for (i=0; i<nparams; ++i)
   {
      if (params[i] == NULL ||
          !png_check_fp_string(params[i], strlen(params[i])))
      {
         png_chunk_report(png_ptr, "Invalid format for pCAL parameter",
               PNG_CHUNK_WRITE_ERROR);
         return;
      }
   }

   info_ptr->pcal_purpose = png_voidcast(png_charp,
       png_malloc_warn(png_ptr, length));

   if (info_ptr->pcal_purpose == NULL)
   {
      png_chunk_report(png_ptr, "Insufficient memory for pCAL purpose",
            PNG_CHUNK_WRITE_ERROR);
      return;
   }

   memcpy(info_ptr->pcal_purpose, purpose, length);

   png_debug(3, "storing X0, X1, type, and nparams in info");
   info_ptr->pcal_X0 = X0;
   info_ptr->pcal_X1 = X1;
   info_ptr->pcal_type = (png_byte)type;
   info_ptr->pcal_nparams = (png_byte)nparams;

   length = strlen(units) + 1;
   png_debug1(3, "allocating units for info (%lu bytes)",
       (unsigned long)length);

   info_ptr->pcal_units = png_voidcast(png_charp,
       png_malloc_warn(png_ptr, length));

   if (info_ptr->pcal_units == NULL)
   {
      png_warning(png_ptr, "Insufficient memory for pCAL units");

      return;
   }

   memcpy(info_ptr->pcal_units, units, length);

   info_ptr->pcal_params = png_voidcast(png_charpp, png_malloc_warn(png_ptr,
       (size_t)(((unsigned int)nparams + 1) * (sizeof (png_charp)))));

   if (info_ptr->pcal_params == NULL)
   {
      png_warning(png_ptr, "Insufficient memory for pCAL params");

      return;
   }

   memset(info_ptr->pcal_params, 0, ((unsigned int)nparams + 1) *
       (sizeof (png_charp)));

   for (i = 0; i < nparams; i++)
   {
      length = strlen(params[i]) + 1;
      png_debug2(3, "allocating parameter %d for info (%lu bytes)", i,
          (unsigned long)length);

      info_ptr->pcal_params[i] = (png_charp)png_malloc_warn(png_ptr, length);

      if (info_ptr->pcal_params[i] == NULL)
      {
         png_warning(png_ptr, "Insufficient memory for pCAL parameter");

         return;
      }

      memcpy(info_ptr->pcal_params[i], params[i], length);
   }

   info_ptr->valid |= PNG_INFO_pCAL;
   info_ptr->free_me |= PNG_FREE_PCAL;
}
#endif

#ifdef PNG_sCAL_SUPPORTED
void PNGAPI
png_set_sCAL_s(png_const_structrp png_ptr, png_inforp info_ptr,
    int unit, png_const_charp swidth, png_const_charp sheight)
{
   size_t lengthw = 0, lengthh = 0;

   png_debug1(1, "in %s storage function", "sCAL");

   if (png_ptr == NULL || info_ptr == NULL)
      return;

   /* Double check the unit (should never get here with an invalid
    * unit unless this is an API call.)
    */
   if (unit != 1 && unit != 2)
      png_error(png_ptr, "Invalid sCAL unit");

   if (swidth == NULL || (lengthw = strlen(swidth)) == 0 ||
       swidth[0] == 45 /* '-' */ || !png_check_fp_string(swidth, lengthw))
      png_error(png_ptr, "Invalid sCAL width");

   if (sheight == NULL || (lengthh = strlen(sheight)) == 0 ||
       sheight[0] == 45 /* '-' */ || !png_check_fp_string(sheight, lengthh))
      png_error(png_ptr, "Invalid sCAL height");

   info_ptr->scal_unit = (png_byte)unit;

   ++lengthw;

   png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthw);

   info_ptr->scal_s_width = png_voidcast(png_charp,
       png_malloc_warn(png_ptr, lengthw));

   if (info_ptr->scal_s_width == NULL)
   {
      png_warning(png_ptr, "Memory allocation failed while processing sCAL");

      return;
   }

   memcpy(info_ptr->scal_s_width, swidth, lengthw);

   ++lengthh;

   png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthh);

   info_ptr->scal_s_height = png_voidcast(png_charp,
       png_malloc_warn(png_ptr, lengthh));

   if (info_ptr->scal_s_height == NULL)
   {
      png_free (png_ptr, info_ptr->scal_s_width);
      info_ptr->scal_s_width = NULL;

      png_warning(png_ptr, "Memory allocation failed while processing sCAL");

      return;
   }

   memcpy(info_ptr->scal_s_height, sheight, lengthh);

   info_ptr->valid |= PNG_INFO_sCAL;
   info_ptr->free_me |= PNG_FREE_SCAL;
}

#  ifdef PNG_FLOATING_POINT_SUPPORTED
void PNGAPI
png_set_sCAL(png_const_structrp png_ptr, png_inforp info_ptr, int unit,
    double width, double height)
{
   png_debug1(1, "in %s storage function", "sCAL");

   /* Check the arguments. */
   if (width <= 0)
      png_warning(png_ptr, "Invalid sCAL width ignored");

   else if (height <= 0)
      png_warning(png_ptr, "Invalid sCAL height ignored");

   else
   {
      /* Convert 'width' and 'height' to ASCII. */
      char swidth[PNG_sCAL_MAX_DIGITS+1];
      char sheight[PNG_sCAL_MAX_DIGITS+1];

      png_ascii_from_fp(png_ptr, swidth, (sizeof swidth), width,
          PNG_sCAL_PRECISION);
      png_ascii_from_fp(png_ptr, sheight, (sizeof sheight), height,
          PNG_sCAL_PRECISION);

      png_set_sCAL_s(png_ptr, info_ptr, unit, swidth, sheight);
   }
}
#  endif

#  ifdef PNG_FIXED_POINT_SUPPORTED
void PNGAPI
png_set_sCAL_fixed(png_const_structrp png_ptr, png_inforp info_ptr, int unit,
    png_fixed_point width, png_fixed_point height)
{
   png_debug1(1, "in %s storage function", "sCAL");

   /* Check the arguments. */
   if (width <= 0)
      png_warning(png_ptr, "Invalid sCAL width ignored");

   else if (height <= 0)
      png_warning(png_ptr, "Invalid sCAL height ignored");

   else
   {
      /* Convert 'width' and 'height' to ASCII. */
      char swidth[PNG_sCAL_MAX_DIGITS+1];
      char sheight[PNG_sCAL_MAX_DIGITS+1];

      png_ascii_from_fixed(png_ptr, swidth, (sizeof swidth), width);
      png_ascii_from_fixed(png_ptr, sheight, (sizeof sheight), height);

      png_set_sCAL_s(png_ptr, info_ptr, unit, swidth, sheight);
   }
}
#  endif
#endif

#ifdef PNG_pHYs_SUPPORTED
void PNGAPI
png_set_pHYs(png_const_structrp png_ptr, png_inforp info_ptr,
    png_uint_32 res_x, png_uint_32 res_y, int unit_type)
{
   png_debug1(1, "in %s storage function", "pHYs");

   if (png_ptr == NULL || info_ptr == NULL)
      return;

   info_ptr->x_pixels_per_unit = res_x;
   info_ptr->y_pixels_per_unit = res_y;
   info_ptr->phys_unit_type = (png_byte)unit_type;
   info_ptr->valid |= PNG_INFO_pHYs;
}
#endif

void PNGAPI
png_set_PLTE(png_structrp png_ptr, png_inforp info_ptr,
    png_const_colorp palette, int num_palette)
{

   png_uint_32 max_palette_length;

   png_debug1(1, "in %s storage function", "PLTE");

   if (png_ptr == NULL || info_ptr == NULL)
      return;

   max_palette_length = (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ?
      (1 << info_ptr->bit_depth) : PNG_MAX_PALETTE_LENGTH;

   if (num_palette < 0 || num_palette > (int) max_palette_length)
   {
      if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
         png_error(png_ptr, "Invalid palette length");

      else
      {
         png_warning(png_ptr, "Invalid palette length");

         return;
      }
   }

   if ((num_palette > 0 && palette == NULL) ||
      (num_palette == 0
#        ifdef PNG_MNG_FEATURES_SUPPORTED
            && (png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) == 0
#        endif
      ))
   {
      png_error(png_ptr, "Invalid palette");
   }

   /* It may not actually be necessary to set png_ptr->palette here;
    * we do it for backward compatibility with the way the png_handle_tRNS
    * function used to do the allocation.
    *
    * 1.6.0: the above statement appears to be incorrect; something has to set
    * the palette inside png_struct on read.
    */
   png_free_data(png_ptr, info_ptr, PNG_FREE_PLTE, 0);

   /* Changed in libpng-1.2.1 to allocate PNG_MAX_PALETTE_LENGTH instead
    * of num_palette entries, in case of an invalid PNG file or incorrect
    * call to png_set_PLTE() with too-large sample values.
    */
   png_ptr->palette = png_voidcast(png_colorp, png_calloc(png_ptr,
       PNG_MAX_PALETTE_LENGTH * (sizeof (png_color))));

   if (num_palette > 0)
      memcpy(png_ptr->palette, palette, (unsigned int)num_palette *
          (sizeof (png_color)));
   info_ptr->palette = png_ptr->palette;
   info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette;

   info_ptr->free_me |= PNG_FREE_PLTE;

   info_ptr->valid |= PNG_INFO_PLTE;
}

#ifdef PNG_sBIT_SUPPORTED
void PNGAPI
png_set_sBIT(png_const_structrp png_ptr, png_inforp info_ptr,
    png_const_color_8p sig_bit)
{
   png_debug1(1, "in %s storage function", "sBIT");

   if (png_ptr == NULL || info_ptr == NULL || sig_bit == NULL)
      return;

   info_ptr->sig_bit = *sig_bit;
   info_ptr->valid |= PNG_INFO_sBIT;
}
#endif

#ifdef PNG_sRGB_SUPPORTED
void PNGAPI
png_set_sRGB(png_const_structrp png_ptr, png_inforp info_ptr, int srgb_intent)
{
   png_debug1(1, "in %s storage function", "sRGB");

   if (png_ptr == NULL || info_ptr == NULL)
      return;

   (void)png_colorspace_set_sRGB(png_ptr, &info_ptr->colorspace, srgb_intent);
   png_colorspace_sync_info(png_ptr, info_ptr);
}

void PNGAPI
png_set_sRGB_gAMA_and_cHRM(png_const_structrp png_ptr, png_inforp info_ptr,
    int srgb_intent)
{
   png_debug1(1, "in %s storage function", "sRGB_gAMA_and_cHRM");

   if (png_ptr == NULL || info_ptr == NULL)
      return;

   if (png_colorspace_set_sRGB(png_ptr, &info_ptr->colorspace,
       srgb_intent) != 0)
   {
      /* This causes the gAMA and cHRM to be written too */
      info_ptr->colorspace.flags |=
         PNG_COLORSPACE_FROM_gAMA|PNG_COLORSPACE_FROM_cHRM;
   }

   png_colorspace_sync_info(png_ptr, info_ptr);
}
#endif /* sRGB */


#ifdef PNG_iCCP_SUPPORTED
void PNGAPI
png_set_iCCP(png_const_structrp png_ptr, png_inforp info_ptr,
    png_const_charp name, int compression_type,
    png_const_bytep profile, png_uint_32 proflen)
{
   png_charp new_iccp_name;
   png_bytep new_iccp_profile;
   size_t length;

   png_debug1(1, "in %s storage function", "iCCP");

   if (png_ptr == NULL || info_ptr == NULL || name == NULL || profile == NULL)
      return;

   if (compression_type != PNG_COMPRESSION_TYPE_BASE)
      png_app_error(png_ptr, "Invalid iCCP compression method");

   /* Set the colorspace first because this validates the profile; do not
    * override previously set app cHRM or gAMA here (because likely as not the
    * application knows better than libpng what the correct values are.)  Pass
    * the info_ptr color_type field to png_colorspace_set_ICC because in the
    * write case it has not yet been stored in png_ptr.
    */
   {
      int result = png_colorspace_set_ICC(png_ptr, &info_ptr->colorspace, name,
          proflen, profile, info_ptr->color_type);

      png_colorspace_sync_info(png_ptr, info_ptr);

      /* Don't do any of the copying if the profile was bad, or inconsistent. */
      if (result == 0)
         return;

      /* But do write the gAMA and cHRM chunks from the profile. */
      info_ptr->colorspace.flags |=
         PNG_COLORSPACE_FROM_gAMA|PNG_COLORSPACE_FROM_cHRM;
   }

   length = strlen(name)+1;
   new_iccp_name = png_voidcast(png_charp, png_malloc_warn(png_ptr, length));

   if (new_iccp_name == NULL)
   {
      png_benign_error(png_ptr, "Insufficient memory to process iCCP chunk");

      return;
   }

   memcpy(new_iccp_name, name, length);
   new_iccp_profile = png_voidcast(png_bytep,
       png_malloc_warn(png_ptr, proflen));

   if (new_iccp_profile == NULL)
   {
      png_free(png_ptr, new_iccp_name);
      png_benign_error(png_ptr,
          "Insufficient memory to process iCCP profile");

      return;
   }

   memcpy(new_iccp_profile, profile, proflen);

   png_free_data(png_ptr, info_ptr, PNG_FREE_ICCP, 0);

   info_ptr->iccp_proflen = proflen;
   info_ptr->iccp_name = new_iccp_name;
   info_ptr->iccp_profile = new_iccp_profile;
   info_ptr->free_me |= PNG_FREE_ICCP;
   info_ptr->valid |= PNG_INFO_iCCP;
}
#endif

#ifdef PNG_TEXT_SUPPORTED
void PNGAPI
png_set_text(png_const_structrp png_ptr, png_inforp info_ptr,
    png_const_textp text_ptr, int num_text)
{
   int ret;
   ret = png_set_text_2(png_ptr, info_ptr, text_ptr, num_text);

   if (ret != 0)
      png_error(png_ptr, "Insufficient memory to store text");
}

int /* PRIVATE */
png_set_text_2(png_const_structrp png_ptr, png_inforp info_ptr,
    png_const_textp text_ptr, int num_text)
{
   int i;

   png_debug1(1, "in %lx storage function", png_ptr == NULL ? 0xabadca11U :
      (unsigned long)png_ptr->chunk_name);

   if (png_ptr == NULL || info_ptr == NULL || num_text <= 0 || text_ptr == NULL)
      return(0);

   /* Make sure we have enough space in the "text" array in info_struct
    * to hold all of the incoming text_ptr objects.  This compare can't overflow
    * because max_text >= num_text (anyway, subtract of two positive integers
    * can't overflow in any case.)
    */
   if (num_text > info_ptr->max_text - info_ptr->num_text)
   {
      int old_num_text = info_ptr->num_text;
      int max_text;
      png_textp new_text = NULL;

      /* Calculate an appropriate max_text, checking for overflow. */
      max_text = old_num_text;
      if (num_text <= INT_MAX - max_text)
      {
         max_text += num_text;

         /* Round up to a multiple of 8 */
         if (max_text < INT_MAX-8)
            max_text = (max_text + 8) & ~0x7;

         else
            max_text = INT_MAX;

         /* Now allocate a new array and copy the old members in; this does all
          * the overflow checks.
          */
         new_text = png_voidcast(png_textp,png_realloc_array(png_ptr,
             info_ptr->text, old_num_text, max_text-old_num_text,
             sizeof *new_text));
      }

      if (new_text == NULL)
      {
         png_chunk_report(png_ptr, "too many text chunks",
             PNG_CHUNK_WRITE_ERROR);

         return 1;
      }

      png_free(png_ptr, info_ptr->text);

      info_ptr->text = new_text;
      info_ptr->free_me |= PNG_FREE_TEXT;
      info_ptr->max_text = max_text;
      /* num_text is adjusted below as the entries are copied in */

      png_debug1(3, "allocated %d entries for info_ptr->text", max_text);
   }

   for (i = 0; i < num_text; i++)
   {
      size_t text_length, key_len;
      size_t lang_len, lang_key_len;
      png_textp textp = &(info_ptr->text[info_ptr->num_text]);

      if (text_ptr[i].key == NULL)
          continue;

      if (text_ptr[i].compression < PNG_TEXT_COMPRESSION_NONE ||
          text_ptr[i].compression >= PNG_TEXT_COMPRESSION_LAST)
      {
         png_chunk_report(png_ptr, "text compression mode is out of range",
             PNG_CHUNK_WRITE_ERROR);
         continue;
      }

      key_len = strlen(text_ptr[i].key);

      if (text_ptr[i].compression <= 0)
      {
         lang_len = 0;
         lang_key_len = 0;
      }

      else
#  ifdef PNG_iTXt_SUPPORTED
      {
         /* Set iTXt data */

         if (text_ptr[i].lang != NULL)
            lang_len = strlen(text_ptr[i].lang);

         else
            lang_len = 0;

         if (text_ptr[i].lang_key != NULL)
            lang_key_len = strlen(text_ptr[i].lang_key);

         else
            lang_key_len = 0;
      }
#  else /* iTXt */
      {
         png_chunk_report(png_ptr, "iTXt chunk not supported",
             PNG_CHUNK_WRITE_ERROR);
         continue;
      }
#  endif

      if (text_ptr[i].text == NULL || text_ptr[i].text[0] == '\0')
      {
         text_length = 0;
#  ifdef PNG_iTXt_SUPPORTED
         if (text_ptr[i].compression > 0)
            textp->compression = PNG_ITXT_COMPRESSION_NONE;

         else
#  endif
            textp->compression = PNG_TEXT_COMPRESSION_NONE;
      }

      else
      {
         text_length = strlen(text_ptr[i].text);
         textp->compression = text_ptr[i].compression;
      }

      textp->key = png_voidcast(png_charp,png_malloc_base(png_ptr,
          key_len + text_length + lang_len + lang_key_len + 4));

      if (textp->key == NULL)
      {
         png_chunk_report(png_ptr, "text chunk: out of memory",
             PNG_CHUNK_WRITE_ERROR);

         return 1;
      }

      png_debug2(2, "Allocated %lu bytes at %p in png_set_text",
          (unsigned long)(png_uint_32)
          (key_len + lang_len + lang_key_len + text_length + 4),
          textp->key);

      memcpy(textp->key, text_ptr[i].key, key_len);
      *(textp->key + key_len) = '\0';

      if (text_ptr[i].compression > 0)
      {
         textp->lang = textp->key + key_len + 1;
         memcpy(textp->lang, text_ptr[i].lang, lang_len);
         *(textp->lang + lang_len) = '\0';
         textp->lang_key = textp->lang + lang_len + 1;
         memcpy(textp->lang_key, text_ptr[i].lang_key, lang_key_len);
         *(textp->lang_key + lang_key_len) = '\0';
         textp->text = textp->lang_key + lang_key_len + 1;
      }

      else
      {
         textp->lang=NULL;
         textp->lang_key=NULL;
         textp->text = textp->key + key_len + 1;
      }

      if (text_length != 0)
         memcpy(textp->text, text_ptr[i].text, text_length);

      *(textp->text + text_length) = '\0';

#  ifdef PNG_iTXt_SUPPORTED
      if (textp->compression > 0)
      {
         textp->text_length = 0;
         textp->itxt_length = text_length;
      }

      else
#  endif
      {
         textp->text_length = text_length;
         textp->itxt_length = 0;
      }

      info_ptr->num_text++;
      png_debug1(3, "transferred text chunk %d", info_ptr->num_text);
   }

   return(0);
}
#endif

#ifdef PNG_tIME_SUPPORTED
void PNGAPI
png_set_tIME(png_const_structrp png_ptr, png_inforp info_ptr,
    png_const_timep mod_time)
{
   png_debug1(1, "in %s storage function", "tIME");

   if (png_ptr == NULL || info_ptr == NULL || mod_time == NULL ||
       (png_ptr->mode & PNG_WROTE_tIME) != 0)
      return;

   if (mod_time->month == 0   || mod_time->month > 12  ||
       mod_time->day   == 0   || mod_time->day   > 31  ||
       mod_time->hour  > 23   || mod_time->minute > 59 ||
       mod_time->second > 60)
   {
      png_warning(png_ptr, "Ignoring invalid time value");

      return;
   }

   info_ptr->mod_time = *mod_time;
   info_ptr->valid |= PNG_INFO_tIME;
}
#endif

#ifdef PNG_tRNS_SUPPORTED
void PNGAPI
png_set_tRNS(png_structrp png_ptr, png_inforp info_ptr,
    png_const_bytep trans_alpha, int num_trans, png_const_color_16p trans_color)
{
   png_debug1(1, "in %s storage function", "tRNS");

   if (png_ptr == NULL || info_ptr == NULL)

      return;

   if (trans_alpha != NULL)
   {
       /* It may not actually be necessary to set png_ptr->trans_alpha here;
        * we do it for backward compatibility with the way the png_handle_tRNS
        * function used to do the allocation.
        *
        * 1.6.0: The above statement is incorrect; png_handle_tRNS effectively
        * relies on png_set_tRNS storing the information in png_struct
        * (otherwise it won't be there for the code in pngrtran.c).
        */

       png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);

       if (num_trans > 0 && num_trans <= PNG_MAX_PALETTE_LENGTH)
       {
         /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */
          info_ptr->trans_alpha = png_voidcast(png_bytep,
              png_malloc(png_ptr, PNG_MAX_PALETTE_LENGTH));
          memcpy(info_ptr->trans_alpha, trans_alpha, (size_t)num_trans);
       }
       png_ptr->trans_alpha = info_ptr->trans_alpha;
   }

   if (trans_color != NULL)
   {
#ifdef PNG_WARNINGS_SUPPORTED
      if (info_ptr->bit_depth < 16)
      {
         int sample_max = (1 << info_ptr->bit_depth) - 1;

         if ((info_ptr->color_type == PNG_COLOR_TYPE_GRAY &&
             trans_color->gray > sample_max) ||
             (info_ptr->color_type == PNG_COLOR_TYPE_RGB &&
             (trans_color->red > sample_max ||
             trans_color->green > sample_max ||
             trans_color->blue > sample_max)))
            png_warning(png_ptr,
                "tRNS chunk has out-of-range samples for bit_depth");
      }
#endif

      info_ptr->trans_color = *trans_color;

      if (num_trans == 0)
         num_trans = 1;
   }

   info_ptr->num_trans = (png_uint_16)num_trans;

   if (num_trans != 0)
   {
      info_ptr->valid |= PNG_INFO_tRNS;
      info_ptr->free_me |= PNG_FREE_TRNS;
   }
}
#endif

#ifdef PNG_sPLT_SUPPORTED
void PNGAPI
png_set_sPLT(png_const_structrp png_ptr,
    png_inforp info_ptr, png_const_sPLT_tp entries, int nentries)
/*
 *  entries        - array of png_sPLT_t structures
 *                   to be added to the list of palettes
 *                   in the info structure.
 *
 *  nentries       - number of palette structures to be
 *                   added.
 */
{
   png_sPLT_tp np;

   if (png_ptr == NULL || info_ptr == NULL || nentries <= 0 || entries == NULL)
      return;

   /* Use the internal realloc function, which checks for all the possible
    * overflows.  Notice that the parameters are (int) and (size_t)
    */
   np = png_voidcast(png_sPLT_tp,png_realloc_array(png_ptr,
       info_ptr->splt_palettes, info_ptr->splt_palettes_num, nentries,
       sizeof *np));

   if (np == NULL)
   {
      /* Out of memory or too many chunks */
      png_chunk_report(png_ptr, "too many sPLT chunks", PNG_CHUNK_WRITE_ERROR);

      return;
   }

   png_free(png_ptr, info_ptr->splt_palettes);
   info_ptr->splt_palettes = np;
   info_ptr->free_me |= PNG_FREE_SPLT;

   np += info_ptr->splt_palettes_num;

   do
   {
      size_t length;

      /* Skip invalid input entries */
      if (entries->name == NULL || entries->entries == NULL)
      {
         /* png_handle_sPLT doesn't do this, so this is an app error */
         png_app_error(png_ptr, "png_set_sPLT: invalid sPLT");
         /* Just skip the invalid entry */
         continue;
      }

      np->depth = entries->depth;

      /* In the event of out-of-memory just return - there's no point keeping
       * on trying to add sPLT chunks.
       */
      length = strlen(entries->name) + 1;
      np->name = png_voidcast(png_charp, png_malloc_base(png_ptr, length));

      if (np->name == NULL)
         break;

      memcpy(np->name, entries->name, length);

      /* IMPORTANT: we have memory now that won't get freed if something else
       * goes wrong; this code must free it.  png_malloc_array produces no
       * warnings; use a png_chunk_report (below) if there is an error.
       */
      np->entries = png_voidcast(png_sPLT_entryp, png_malloc_array(png_ptr,
          entries->nentries, sizeof (png_sPLT_entry)));

      if (np->entries == NULL)
      {
         png_free(png_ptr, np->name);
         np->name = NULL;
         break;
      }

      np->nentries = entries->nentries;
      /* This multiply can't overflow because png_malloc_array has already
       * checked it when doing the allocation.
       */
      memcpy(np->entries, entries->entries,
          (unsigned int)entries->nentries * sizeof (png_sPLT_entry));

      /* Note that 'continue' skips the advance of the out pointer and out
       * count, so an invalid entry is not added.
       */
      info_ptr->valid |= PNG_INFO_sPLT;
      ++(info_ptr->splt_palettes_num);
      ++np;
      ++entries;
   }
   while (--nentries);

   if (nentries > 0)
      png_chunk_report(png_ptr, "sPLT out of memory", PNG_CHUNK_WRITE_ERROR);
}
#endif /* sPLT */

#ifdef PNG_APNG_SUPPORTED
png_uint_32 PNGAPI
png_set_acTL(png_structp png_ptr, png_infop info_ptr,
    png_uint_32 num_frames, png_uint_32 num_plays)
{
    png_debug1(1, "in %s storage function", "acTL");

    if (png_ptr == NULL || info_ptr == NULL)
    {
        png_warning(png_ptr,
                    "Call to png_set_acTL() with NULL png_ptr "
                    "or info_ptr ignored");
        return (0);
    }
    if (num_frames == 0)
    {
        png_warning(png_ptr,
                    "Ignoring attempt to set acTL with num_frames zero");
        return (0);
    }
    if (num_frames > PNG_UINT_31_MAX)
    {
        png_warning(png_ptr,
                    "Ignoring attempt to set acTL with num_frames > 2^31-1");
        return (0);
    }
    if (num_plays > PNG_UINT_31_MAX)
    {
        png_warning(png_ptr,
                    "Ignoring attempt to set acTL with num_plays "
                    "> 2^31-1");
        return (0);
    }

    info_ptr->num_frames = num_frames;
    info_ptr->num_plays = num_plays;

    info_ptr->valid |= PNG_INFO_acTL;

    return (1);
}

/* delay_num and delay_den can hold any 16-bit values including zero */
png_uint_32 PNGAPI
png_set_next_frame_fcTL(png_structp png_ptr, png_infop info_ptr,
    png_uint_32 width, png_uint_32 height,
    png_uint_32 x_offset, png_uint_32 y_offset,
    png_uint_16 delay_num, png_uint_16 delay_den,
    png_byte dispose_op, png_byte blend_op)
{
    png_debug1(1, "in %s storage function", "fcTL");

    if (png_ptr == NULL || info_ptr == NULL)
    {
        png_warning(png_ptr,
                    "Call to png_set_fcTL() with NULL png_ptr or info_ptr "
                    "ignored");
        return (0);
    }

    png_ensure_fcTL_is_valid(png_ptr, width, height, x_offset, y_offset,
                             delay_num, delay_den, dispose_op, blend_op);

    if (blend_op == PNG_BLEND_OP_OVER)
    {
        if (!(png_ptr->color_type & PNG_COLOR_MASK_ALPHA) &&
            !(png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)))
        {
          png_warning(png_ptr, "PNG_BLEND_OP_OVER is meaningless "
                               "and wasteful for opaque images, ignored");
          blend_op = PNG_BLEND_OP_SOURCE;
        }
    }

    info_ptr->next_frame_width = width;
    info_ptr->next_frame_height = height;
    info_ptr->next_frame_x_offset = x_offset;
    info_ptr->next_frame_y_offset = y_offset;
    info_ptr->next_frame_delay_num = delay_num;
    info_ptr->next_frame_delay_den = delay_den;
    info_ptr->next_frame_dispose_op = dispose_op;
    info_ptr->next_frame_blend_op = blend_op;

    info_ptr->valid |= PNG_INFO_fcTL;

    return (1);
}

void /* PRIVATE */
png_ensure_fcTL_is_valid(png_structp png_ptr,
    png_uint_32 width, png_uint_32 height,
    png_uint_32 x_offset, png_uint_32 y_offset,
    png_uint_16 delay_num, png_uint_16 delay_den,
    png_byte dispose_op, png_byte blend_op)
{
    if (width == 0 || width > PNG_UINT_31_MAX)
        png_error(png_ptr, "invalid width in fcTL (> 2^31-1)");
    if (height == 0 || height > PNG_UINT_31_MAX)
        png_error(png_ptr, "invalid height in fcTL (> 2^31-1)");
    if (x_offset > PNG_UINT_31_MAX)
        png_error(png_ptr, "invalid x_offset in fcTL (> 2^31-1)");
    if (y_offset > PNG_UINT_31_MAX)
        png_error(png_ptr, "invalid y_offset in fcTL (> 2^31-1)");
    if (width + x_offset > png_ptr->first_frame_width ||
        height + y_offset > png_ptr->first_frame_height)
        png_error(png_ptr, "dimensions of a frame are greater than"
                           "the ones in IHDR");

    if (dispose_op != PNG_DISPOSE_OP_NONE &&
        dispose_op != PNG_DISPOSE_OP_BACKGROUND &&
        dispose_op != PNG_DISPOSE_OP_PREVIOUS)
        png_error(png_ptr, "invalid dispose_op in fcTL");

    if (blend_op != PNG_BLEND_OP_SOURCE &&
        blend_op != PNG_BLEND_OP_OVER)
        png_error(png_ptr, "invalid blend_op in fcTL");

    PNG_UNUSED(delay_num)
    PNG_UNUSED(delay_den)
}

png_uint_32 PNGAPI
png_set_first_frame_is_hidden(png_structp png_ptr, png_infop info_ptr,
                              png_byte is_hidden)
{
    png_debug(1, "in png_first_frame_is_hidden()");

    if (png_ptr == NULL)
        return 0;

    if (is_hidden)
        png_ptr->apng_flags |= PNG_FIRST_FRAME_HIDDEN;
    else
        png_ptr->apng_flags &= ~PNG_FIRST_FRAME_HIDDEN;

    PNG_UNUSED(info_ptr)

    return 1;
}
#endif /* PNG_APNG_SUPPORTED */

#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
static png_byte
check_location(png_const_structrp png_ptr, int location)
{
   location &= (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT);

   /* New in 1.6.0; copy the location and check it.  This is an API
    * change; previously the app had to use the
    * png_set_unknown_chunk_location API below for each chunk.
    */
   if (location == 0 && (png_ptr->mode & PNG_IS_READ_STRUCT) == 0)
   {
      /* Write struct, so unknown chunks come from the app */
      png_app_warning(png_ptr,
          "png_set_unknown_chunks now expects a valid location");
      /* Use the old behavior */
      location = (png_byte)(png_ptr->mode &
          (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT));
   }

   /* This need not be an internal error - if the app calls
    * png_set_unknown_chunks on a read pointer it must get the location right.
    */
   if (location == 0)
      png_error(png_ptr, "invalid location in png_set_unknown_chunks");

   /* Now reduce the location to the top-most set bit by removing each least
    * significant bit in turn.
    */
   while (location != (location & -location))
      location &= ~(location & -location);

   /* The cast is safe because 'location' is a bit mask and only the low four
    * bits are significant.
    */
   return (png_byte)location;
}

void PNGAPI
png_set_unknown_chunks(png_const_structrp png_ptr,
    png_inforp info_ptr, png_const_unknown_chunkp unknowns, int num_unknowns)
{
   png_unknown_chunkp np;

   if (png_ptr == NULL || info_ptr == NULL || num_unknowns <= 0 ||
       unknowns == NULL)
      return;

   /* Check for the failure cases where support has been disabled at compile
    * time.  This code is hardly ever compiled - it's here because
    * STORE_UNKNOWN_CHUNKS is set by both read and write code (compiling in this
    * code) but may be meaningless if the read or write handling of unknown
    * chunks is not compiled in.
    */
#  if !defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) && \
      defined(PNG_READ_SUPPORTED)
      if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
      {
         png_app_error(png_ptr, "no unknown chunk support on read");

         return;
      }
#  endif
#  if !defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED) && \
      defined(PNG_WRITE_SUPPORTED)
      if ((png_ptr->mode & PNG_IS_READ_STRUCT) == 0)
      {
         png_app_error(png_ptr, "no unknown chunk support on write");

         return;
      }
#  endif

   /* Prior to 1.6.0 this code used png_malloc_warn; however, this meant that
    * unknown critical chunks could be lost with just a warning resulting in
    * undefined behavior.  Now png_chunk_report is used to provide behavior
    * appropriate to read or write.
    */
   np = png_voidcast(png_unknown_chunkp, png_realloc_array(png_ptr,
       info_ptr->unknown_chunks, info_ptr->unknown_chunks_num, num_unknowns,
       sizeof *np));

   if (np == NULL)
   {
      png_chunk_report(png_ptr, "too many unknown chunks",
          PNG_CHUNK_WRITE_ERROR);

      return;
   }

   png_free(png_ptr, info_ptr->unknown_chunks);
   info_ptr->unknown_chunks = np; /* safe because it is initialized */
   info_ptr->free_me |= PNG_FREE_UNKN;

   np += info_ptr->unknown_chunks_num;

   /* Increment unknown_chunks_num each time round the loop to protect the
    * just-allocated chunk data.
    */
   for (; num_unknowns > 0; --num_unknowns, ++unknowns)
   {
      memcpy(np->name, unknowns->name, (sizeof np->name));
      np->name[(sizeof np->name)-1] = '\0';
      np->location = check_location(png_ptr, unknowns->location);

      if (unknowns->size == 0)
      {
         np->data = NULL;
         np->size = 0;
      }

      else
      {
         np->data = png_voidcast(png_bytep,
             png_malloc_base(png_ptr, unknowns->size));

         if (np->data == NULL)
         {
            png_chunk_report(png_ptr, "unknown chunk: out of memory",
                PNG_CHUNK_WRITE_ERROR);
            /* But just skip storing the unknown chunk */
            continue;
         }

         memcpy(np->data, unknowns->data, unknowns->size);
         np->size = unknowns->size;
      }

      /* These increments are skipped on out-of-memory for the data - the
       * unknown chunk entry gets overwritten if the png_chunk_report returns.
       * This is correct in the read case (the chunk is just dropped.)
       */
      ++np;
      ++(info_ptr->unknown_chunks_num);
   }
}

void PNGAPI
png_set_unknown_chunk_location(png_const_structrp png_ptr, png_inforp info_ptr,
    int chunk, int location)
{
   /* This API is pretty pointless in 1.6.0 because the location can be set
    * before the call to png_set_unknown_chunks.
    *
    * TODO: add a png_app_warning in 1.7
    */
   if (png_ptr != NULL && info_ptr != NULL && chunk >= 0 &&
      chunk < info_ptr->unknown_chunks_num)
   {
      if ((location & (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT)) == 0)
      {
         png_app_error(png_ptr, "invalid unknown chunk location");
         /* Fake out the pre 1.6.0 behavior: */
         if (((unsigned int)location & PNG_HAVE_IDAT) != 0) /* undocumented! */
            location = PNG_AFTER_IDAT;

         else
            location = PNG_HAVE_IHDR; /* also undocumented */
      }

      info_ptr->unknown_chunks[chunk].location =
         check_location(png_ptr, location);
   }
}
#endif /* STORE_UNKNOWN_CHUNKS */

#ifdef PNG_MNG_FEATURES_SUPPORTED
png_uint_32 PNGAPI
png_permit_mng_features (png_structrp png_ptr, png_uint_32 mng_features)
{
   png_debug(1, "in png_permit_mng_features");

   if (png_ptr == NULL)
      return 0;

   png_ptr->mng_features_permitted = mng_features & PNG_ALL_MNG_FEATURES;

   return png_ptr->mng_features_permitted;
}
#endif

#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
static unsigned int
add_one_chunk(png_bytep list, unsigned int count, png_const_bytep add, int keep)
{
   unsigned int i;

   /* Utility function: update the 'keep' state of a chunk if it is already in
    * the list, otherwise add it to the list.
    */
   for (i=0; i<count; ++i, list += 5)
   {
      if (memcmp(list, add, 4) == 0)
      {
         list[4] = (png_byte)keep;

         return count;
      }
   }

   if (keep != PNG_HANDLE_CHUNK_AS_DEFAULT)
   {
      ++count;
      memcpy(list, add, 4);
      list[4] = (png_byte)keep;
   }

   return count;
}

void PNGAPI
png_set_keep_unknown_chunks(png_structrp png_ptr, int keep,
    png_const_bytep chunk_list, int num_chunks_in)
{
   png_bytep new_list;
   unsigned int num_chunks, old_num_chunks;

   if (png_ptr == NULL)
      return;

   if (keep < 0 || keep >= PNG_HANDLE_CHUNK_LAST)
   {
      png_app_error(png_ptr, "png_set_keep_unknown_chunks: invalid keep");

      return;
   }

   if (num_chunks_in <= 0)
   {
      png_ptr->unknown_default = keep;

      /* '0' means just set the flags, so stop here */
      if (num_chunks_in == 0)
        return;
   }

   if (num_chunks_in < 0)
   {
      /* Ignore all unknown chunks and all chunks recognized by
       * libpng except for IHDR, PLTE, tRNS, IDAT, and IEND
       */
      static const png_byte chunks_to_ignore[] = {
         98,  75,  71,  68, '\0',  /* bKGD */
         99,  72,  82,  77, '\0',  /* cHRM */
        101,  88,  73, 102, '\0',  /* eXIf */
        103,  65,  77,  65, '\0',  /* gAMA */
        104,  73,  83,  84, '\0',  /* hIST */
        105,  67,  67,  80, '\0',  /* iCCP */
        105,  84,  88, 116, '\0',  /* iTXt */
        111,  70,  70, 115, '\0',  /* oFFs */
        112,  67,  65,  76, '\0',  /* pCAL */
        112,  72,  89, 115, '\0',  /* pHYs */
        115,  66,  73,  84, '\0',  /* sBIT */
        115,  67,  65,  76, '\0',  /* sCAL */
        115,  80,  76,  84, '\0',  /* sPLT */
        115,  84,  69,  82, '\0',  /* sTER */
        115,  82,  71,  66, '\0',  /* sRGB */
        116,  69,  88, 116, '\0',  /* tEXt */
        116,  73,  77,  69, '\0',  /* tIME */
        122,  84,  88, 116, '\0'   /* zTXt */
      };

      chunk_list = chunks_to_ignore;
      num_chunks = (unsigned int)/*SAFE*/(sizeof chunks_to_ignore)/5U;
   }

   else /* num_chunks_in > 0 */
   {
      if (chunk_list == NULL)
      {
         /* Prior to 1.6.0 this was silently ignored, now it is an app_error
          * which can be switched off.
          */
         png_app_error(png_ptr, "png_set_keep_unknown_chunks: no chunk list");

         return;
      }

      num_chunks = (unsigned int)num_chunks_in;
   }

   old_num_chunks = png_ptr->num_chunk_list;
   if (png_ptr->chunk_list == NULL)
      old_num_chunks = 0;

   /* Since num_chunks is always restricted to UINT_MAX/5 this can't overflow.
    */
   if (num_chunks + old_num_chunks > UINT_MAX/5)
   {
      png_app_error(png_ptr, "png_set_keep_unknown_chunks: too many chunks");

      return;
   }

   /* If these chunks are being reset to the default then no more memory is
    * required because add_one_chunk above doesn't extend the list if the 'keep'
    * parameter is the default.
    */
   if (keep != 0)
   {
      new_list = png_voidcast(png_bytep, png_malloc(png_ptr,
          5 * (num_chunks + old_num_chunks)));

      if (old_num_chunks > 0)
         memcpy(new_list, png_ptr->chunk_list, 5*old_num_chunks);
   }

   else if (old_num_chunks > 0)
      new_list = png_ptr->chunk_list;

   else
      new_list = NULL;

   /* Add the new chunks together with each one's handling code.  If the chunk
    * already exists the code is updated, otherwise the chunk is added to the
    * end.  (In libpng 1.6.0 order no longer matters because this code enforces
    * the earlier convention that the last setting is the one that is used.)
    */
   if (new_list != NULL)
   {
      png_const_bytep inlist;
      png_bytep outlist;
      unsigned int i;

      for (i=0; i<num_chunks; ++i)
      {
         old_num_chunks = add_one_chunk(new_list, old_num_chunks,
             chunk_list+5*i, keep);
      }

      /* Now remove any spurious 'default' entries. */
      num_chunks = 0;
      for (i=0, inlist=outlist=new_list; i<old_num_chunks; ++i, inlist += 5)
      {
         if (inlist[4])
         {
            if (outlist != inlist)
               memcpy(outlist, inlist, 5);
            outlist += 5;
            ++num_chunks;
         }
      }

      /* This means the application has removed all the specialized handling. */
      if (num_chunks == 0)
      {
         if (png_ptr->chunk_list != new_list)
            png_free(png_ptr, new_list);

         new_list = NULL;
      }
   }

   else
      num_chunks = 0;

   png_ptr->num_chunk_list = num_chunks;

   if (png_ptr->chunk_list != new_list)
   {
      if (png_ptr->chunk_list != NULL)
         png_free(png_ptr, png_ptr->chunk_list);

      png_ptr->chunk_list = new_list;
   }
}
#endif

#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
void PNGAPI
png_set_read_user_chunk_fn(png_structrp png_ptr, png_voidp user_chunk_ptr,
    png_user_chunk_ptr read_user_chunk_fn)
{
   png_debug(1, "in png_set_read_user_chunk_fn");

   if (png_ptr == NULL)
      return;

   png_ptr->read_user_chunk_fn = read_user_chunk_fn;
   png_ptr->user_chunk_ptr = user_chunk_ptr;
}
#endif

#ifdef PNG_INFO_IMAGE_SUPPORTED
void PNGAPI
png_set_rows(png_const_structrp png_ptr, png_inforp info_ptr,
    png_bytepp row_pointers)
{
   png_debug1(1, "in %s storage function", "rows");

   if (png_ptr == NULL || info_ptr == NULL)
      return;

   if (info_ptr->row_pointers != NULL &&
       (info_ptr->row_pointers != row_pointers))
      png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);

   info_ptr->row_pointers = row_pointers;

   if (row_pointers != NULL)
      info_ptr->valid |= PNG_INFO_IDAT;
}
#endif

void PNGAPI
png_set_compression_buffer_size(png_structrp png_ptr, size_t size)
{
   if (png_ptr == NULL)
      return;

   if (size == 0 || size > PNG_UINT_31_MAX)
      png_error(png_ptr, "invalid compression buffer size");

#  ifdef PNG_SEQUENTIAL_READ_SUPPORTED
   if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
   {
      png_ptr->IDAT_read_size = (png_uint_32)size; /* checked above */
      return;
   }
#  endif

#  ifdef PNG_WRITE_SUPPORTED
   if ((png_ptr->mode & PNG_IS_READ_STRUCT) == 0)
   {
      if (png_ptr->zowner != 0)
      {
         png_warning(png_ptr,
             "Compression buffer size cannot be changed because it is in use");

         return;
      }

#ifndef __COVERITY__
      /* Some compilers complain that this is always false.  However, it
       * can be true when integer overflow happens.
       */
      if (size > ZLIB_IO_MAX)
      {
         png_warning(png_ptr,
             "Compression buffer size limited to system maximum");
         size = ZLIB_IO_MAX; /* must fit */
      }
#endif

      if (size < 6)
      {
         /* Deflate will potentially go into an infinite loop on a SYNC_FLUSH
          * if this is permitted.
          */
         png_warning(png_ptr,
             "Compression buffer size cannot be reduced below 6");

         return;
      }

      if (png_ptr->zbuffer_size != size)
      {
         png_free_buffer_list(png_ptr, &png_ptr->zbuffer_list);
         png_ptr->zbuffer_size = (uInt)size;
      }
   }
#  endif
}

void PNGAPI
png_set_invalid(png_const_structrp png_ptr, png_inforp info_ptr, int mask)
{
   if (png_ptr != NULL && info_ptr != NULL)
      info_ptr->valid &= (unsigned int)(~mask);
}


#ifdef PNG_SET_USER_LIMITS_SUPPORTED
/* This function was added to libpng 1.2.6 */
void PNGAPI
png_set_user_limits (png_structrp png_ptr, png_uint_32 user_width_max,
    png_uint_32 user_height_max)
{
   /* Images with dimensions larger than these limits will be
    * rejected by png_set_IHDR().  To accept any PNG datastream
    * regardless of dimensions, set both limits to 0x7fffffff.
    */
   if (png_ptr == NULL)
      return;

   png_ptr->user_width_max = user_width_max;
   png_ptr->user_height_max = user_height_max;
}

/* This function was added to libpng 1.4.0 */
void PNGAPI
png_set_chunk_cache_max (png_structrp png_ptr, png_uint_32 user_chunk_cache_max)
{
   if (png_ptr != NULL)
      png_ptr->user_chunk_cache_max = user_chunk_cache_max;
}

/* This function was added to libpng 1.4.1 */
void PNGAPI
png_set_chunk_malloc_max (png_structrp png_ptr,
    png_alloc_size_t user_chunk_malloc_max)
{
   if (png_ptr != NULL)
      png_ptr->user_chunk_malloc_max = user_chunk_malloc_max;
}
#endif /* ?SET_USER_LIMITS */


#ifdef PNG_BENIGN_ERRORS_SUPPORTED
void PNGAPI
png_set_benign_errors(png_structrp png_ptr, int allowed)
{
   png_debug(1, "in png_set_benign_errors");

   /* If allowed is 1, png_benign_error() is treated as a warning.
    *
    * If allowed is 0, png_benign_error() is treated as an error (which
    * is the default behavior if png_set_benign_errors() is not called).
    */

   if (allowed != 0)
      png_ptr->flags |= PNG_FLAG_BENIGN_ERRORS_WARN |
         PNG_FLAG_APP_WARNINGS_WARN | PNG_FLAG_APP_ERRORS_WARN;

   else
      png_ptr->flags &= ~(PNG_FLAG_BENIGN_ERRORS_WARN |
         PNG_FLAG_APP_WARNINGS_WARN | PNG_FLAG_APP_ERRORS_WARN);
}
#endif /* BENIGN_ERRORS */

#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
   /* Whether to report invalid palette index; added at libng-1.5.10.
    * It is possible for an indexed (color-type==3) PNG file to contain
    * pixels with invalid (out-of-range) indexes if the PLTE chunk has
    * fewer entries than the image's bit-depth would allow. We recover
    * from this gracefully by filling any incomplete palette with zeros
    * (opaque black).  By default, when this occurs libpng will issue
    * a benign error.  This API can be used to override that behavior.
    */
void PNGAPI
png_set_check_for_invalid_index(png_structrp png_ptr, int allowed)
{
   png_debug(1, "in png_set_check_for_invalid_index");

   if (allowed > 0)
      png_ptr->num_palette_max = 0;

   else
      png_ptr->num_palette_max = -1;
}
#endif

#if defined(PNG_TEXT_SUPPORTED) || defined(PNG_pCAL_SUPPORTED) || \
    defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED)
/* Check that the tEXt or zTXt keyword is valid per PNG 1.0 specification,
 * and if invalid, correct the keyword rather than discarding the entire
 * chunk.  The PNG 1.0 specification requires keywords 1-79 characters in
 * length, forbids leading or trailing whitespace, multiple internal spaces,
 * and the non-break space (0x80) from ISO 8859-1.  Returns keyword length.
 *
 * The 'new_key' buffer must be 80 characters in size (for the keyword plus a
 * trailing '\0').  If this routine returns 0 then there was no keyword, or a
 * valid one could not be generated, and the caller must png_error.
 */
png_uint_32 /* PRIVATE */
png_check_keyword(png_structrp png_ptr, png_const_charp key, png_bytep new_key)
{
#ifdef PNG_WARNINGS_SUPPORTED
   png_const_charp orig_key = key;
#endif
   png_uint_32 key_len = 0;
   int bad_character = 0;
   int space = 1;

   png_debug(1, "in png_check_keyword");

   if (key == NULL)
   {
      *new_key = 0;
      return 0;
   }

   while (*key && key_len < 79)
   {
      png_byte ch = (png_byte)*key++;

      if ((ch > 32 && ch <= 126) || (ch >= 161 /*&& ch <= 255*/))
      {
         *new_key++ = ch; ++key_len; space = 0;
      }

      else if (space == 0)
      {
         /* A space or an invalid character when one wasn't seen immediately
          * before; output just a space.
          */
         *new_key++ = 32; ++key_len; space = 1;

         /* If the character was not a space then it is invalid. */
         if (ch != 32)
            bad_character = ch;
      }

      else if (bad_character == 0)
         bad_character = ch; /* just skip it, record the first error */
   }

   if (key_len > 0 && space != 0) /* trailing space */
   {
      --key_len; --new_key;
      if (bad_character == 0)
         bad_character = 32;
   }

   /* Terminate the keyword */
   *new_key = 0;

   if (key_len == 0)
      return 0;

#ifdef PNG_WARNINGS_SUPPORTED
   /* Try to only output one warning per keyword: */
   if (*key != 0) /* keyword too long */
      png_warning(png_ptr, "keyword truncated");

   else if (bad_character != 0)
   {
      PNG_WARNING_PARAMETERS(p)

      png_warning_parameter(p, 1, orig_key);
      png_warning_parameter_signed(p, 2, PNG_NUMBER_FORMAT_02x, bad_character);

      png_formatted_warning(png_ptr, p, "keyword \"@1\": bad character '0x@2'");
   }
#else /* !WARNINGS */
   PNG_UNUSED(png_ptr)
#endif /* !WARNINGS */

   return key_len;
}
#endif /* TEXT || pCAL || iCCP || sPLT */
#endif /* READ || WRITE */