C / C++ / MFC

ULONG util_ConvertHexStringToBin(char *pszHexString, void *pBinaryBuffer, unsigned int uiBufferSize)
{	//Parses the contents of the null terminated text string representing a hexidecimal value, and converts
	//each pair of hex digits as a byte.  The function will convert no more than uiBufferSize bytes worth
	//of hex digits and will also terminate when all hex digit pairs have been parsed.
	//Returns the size of the resulting binary block
	unsigned int	uiHexPairs;
	unsigned int	uiByteIndex;
	char			*pszParse = NULL;
	BYTE			ucTempByte;

	
	uiHexPairs = strlen(pszHexString)/2; //String length divided by 2
	pszParse = pszHexString;

	uiByteIndex = 0;

	//Loop while still HEX pairs to parse and still bytes to fill in Buffer
	while (uiByteIndex < uiBufferSize && uiByteIndex < uiHexPairs)
	{
	    sscanf_s(pszParse, "%2x", &ucTempByte);
	   ((BYTE *)pBinaryBuffer)[uiByteIndex] = ucTempByte;
		pszParse += 2; //Advance string parse pointer 
		uiByteIndex++; //Advance byte index within buffer
	}
		
	return uiByteIndex;
}

int CreateArray(void** data, unsigned int* size)
{
//allocates some array and assigns it to data
}

int main()
{
unsigned char* data = 0;
unsigned int size;
int res = CreateArray(&data, &size);
}