| public static CRC32 ( byte stream, int offset, int length, uint crc, uint &crcTable ) : uint | ||
| stream | byte | |
| offset | int | |
| length | int | |
| crc | uint | |
| crcTable | uint | |
| return | uint | |
public static uint CRC32(byte[] stream, int offset, int length, uint crc, ref uint[] crcTable)
{
uint c;
if (crcTable == null)
{
crcTable = new uint[256];
for (uint n = 0; n <= 255; n++)
{
c = n;
for (var k = 0; k <= 7; k++)
{
if ((c & 1) == 1)
c = 0xEDB88320 ^ ((c >> 1) & 0x7FFFFFFF);
else
c = ((c >> 1) & 0x7FFFFFFF);
}
crcTable[n] = c;
}
}
c = crc ^ 0xffffffff;
var endOffset = offset + length;
for (var i = offset; i < endOffset; i++)
{
c = crcTable[(c ^ stream[i]) & 255] ^ ((c >> 8) & 0xFFFFFF);
}
return c ^ 0xffffffff;
}