public uint DecodeUnsigned(byte[] image, uint offset, ref uint pValue)
{
if (offset >= image.Length)
{
throw new System.BadImageFormatException("NativeArray offset out of bounds");
}
int off = (int)offset;
uint val = R2RReader.ReadByte(image, ref off);
if ((val & 1) == 0)
{
pValue = (val >> 1);
offset += 1;
}
else if ((val & 2) == 0)
{
if (offset + 1 >= image.Length)
{
throw new System.BadImageFormatException("NativeArray offset out of bounds");
}
pValue = (val >> 2) |
((uint)R2RReader.ReadByte(image, ref off) << 6);
offset += 2;
}
else if ((val & 4) == 0)
{
if (offset + 2 >= image.Length)
{
throw new System.BadImageFormatException("NativeArray offset out of bounds");
}
pValue = (val >> 3) |
((uint)R2RReader.ReadByte(image, ref off) << 5) |
((uint)R2RReader.ReadByte(image, ref off) << 13);
offset += 3;
}
else if ((val & 8) == 0)
{
if (offset + 3 >= image.Length)
{
throw new System.BadImageFormatException("NativeArray offset out of bounds");
}
pValue = (val >> 4) |
((uint)R2RReader.ReadByte(image, ref off) << 4) |
((uint)R2RReader.ReadByte(image, ref off) << 12) |
((uint)R2RReader.ReadByte(image, ref off) << 20);
offset += 4;
}
else if ((val & 16) == 0)
{
pValue = R2RReader.ReadUInt32(image, ref off);
offset += 5;
}
else
{
throw new System.BadImageFormatException("NativeArray");
}
return(offset);
}
public bool TryGetAt(byte[] image, uint index, ref uint pOffset)
{
if (index >= _nElements)
{
return(false);
}
uint offset = 0;
if (_entryIndexSize == 0)
{
int i = (int)(_baseOffset + (index / _blockSize));
offset = R2RReader.ReadByte(image, ref i);
}
else if (_entryIndexSize == 1)
{
int i = (int)(_baseOffset + 2 * (index / _blockSize));
offset = R2RReader.ReadUInt16(image, ref i);
}
else
{
int i = (int)(_baseOffset + 4 * (index / _blockSize));
offset = R2RReader.ReadUInt32(image, ref i);
}
offset += _baseOffset;
for (uint bit = _blockSize >> 1; bit > 0; bit >>= 1)
{
uint val = 0;
uint offset2 = DecodeUnsigned(image, offset, ref val);
if ((index & bit) != 0)
{
if ((val & 2) != 0)
{
offset = offset + (val >> 2);
continue;
}
}
else
{
if ((val & 1) != 0)
{
offset = offset2;
continue;
}
}
// Not found
if ((val & 3) == 0)
{
// Matching special leaf node?
if ((val >> 2) == (index & (_blockSize - 1)))
{
offset = offset2;
break;
}
}
return(false);
}
pOffset = offset;
return(true);
}
