winamp/Src/WAT/wa_bits_operation.cpp

39 lines
1.2 KiB
C++

#include "WAT.h"
unsigned char* wa::bits_operation::GetBits(unsigned char* Source, unsigned int NbrOfBits, unsigned int* BufferSize)
{
// check for wrong parameter
if (Source == nullptr || NbrOfBits == 0 || BufferSize == nullptr)
return nullptr;
// variable
unsigned int bitMask = 0;
unsigned int nbrOfByteToRead = 1 + (NbrOfBits-1) / 8;
unsigned char* bufferToReturn = (unsigned char*)malloc(nbrOfByteToRead);
memset(bufferToReturn, 0, nbrOfByteToRead);
*BufferSize = nbrOfByteToRead;
// copy all bytes
if (nbrOfByteToRead > 1)
{
memcpy(bufferToReturn, Source, nbrOfByteToRead - 1);
}
// copy the specific end bits
bitMask = (1 << NbrOfBits - ((nbrOfByteToRead - 1)*8)) - 1;
bufferToReturn[nbrOfByteToRead - 1] = Source[nbrOfByteToRead - 1] & bitMask;
return bufferToReturn;
}
wa::strings::wa_string wa::bits_operation::PrintInBinary(unsigned char* buffer, unsigned int size)
{
wa::strings::wa_string ToReturn = "";
for (unsigned int NbrOfByte = 0; NbrOfByte < size; ++NbrOfByte)
{
for (int IndexBit = 0; IndexBit < 8; ++IndexBit)
ToReturn.append((buffer[NbrOfByte] & (1 << IndexBit)) ? "1" : "0");
ToReturn.append(" ' ");
}
return ToReturn;
}