KSG-Framework/Base64.cpp

#include "Base64.h"

using namespace Framework;

static Framework::Text base64_chars =
"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
"abcdefghijklmnopqrstuvwxyz"
"0123456789+/";

Text Framework::base64Encode(const char* data, int length)
{
	Text result;
	int i = 0;
	int j = 0;
	unsigned char char_array_3[3];
	unsigned char char_array_4[4];
	while (length--)
	{
		char_array_3[i++] = *(data++);
		if (i == 3)
		{
			char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
			char_array_4[1] = (unsigned char)(((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4));
			char_array_4[2] = (unsigned char)(((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6));
			char_array_4[3] = char_array_3[2] & 0x3f;
			for (i = 0; (i < 4); i++)
				result.append((char)base64_chars[char_array_4[i]]);
			i = 0;
		}
	}
	if (i)
	{
		for (j = i; j < 3; j++)
			char_array_3[j] = '\0';
		char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
		char_array_4[1] = (unsigned char)(((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4));
		char_array_4[2] = (unsigned char)(((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6));
		char_array_4[3] = char_array_3[2] & 0x3f;
		for (j = 0; (j < i + 1); j++)
			result.append((char)base64_chars[char_array_4[j]]);
		while ((i++ < 3))
			result.append('=');
	}
	return result;
}

bool Framework::base64Decode(Text base64, char** data, int* length)
{
	int i = 0;
	int j = 0;
	int k = 0;
	int l = 0;
	int n = 0;
	unsigned char char_array_4[4];
	unsigned char char_array_3[3];
	*length = 0;
	while (base64[l])
	{
		if (base64[l] == '=')
			break;
		if ((base64[l] - 'A' < 0 || base64[l] - 'A' > 25) && (base64[l] - 'a' < 0 || base64[l] - 'a' > 25) && (base64[l] - '0' < 0 || base64[l] - '0' > 9))
			return false;
		l++;
	}
	*length = (l * 3) / 4;
	*data = new char[*length + 1];
	while (base64[k])
	{
		char_array_4[i++] = base64[k];
		if (i == 4)
		{
			for (i = 0; i < 4; i++)
				char_array_4[i] = (unsigned char)(base64_chars.positionVon(char_array_4[i]));
			char_array_3[0] = (unsigned char)((char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4));
			char_array_3[1] = (unsigned char)(((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2));
			char_array_3[2] = (unsigned char)(((char_array_4[2] & 0x3) << 6) + char_array_4[3]);
			for (i = 0; (i < 3); i++)
				(*data)[n++] = char_array_3[i];
			i = 0;
		}
		k++;
	}
	if (i)
	{
		for (j = i; j < 4; j++)
			char_array_4[j] = 0;
		for (j = 0; j < 4; j++)
			char_array_4[j] = (unsigned char)(base64_chars.positionVon(char_array_4[j]));
		char_array_3[0] = (unsigned char)((char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4));
		char_array_3[1] = (unsigned char)(((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2));
		char_array_3[2] = (unsigned char)(((char_array_4[2] & 0x3) << 6) + char_array_4[3]);
		for (j = 0; (j < i - 1); j++)
			(*data)[n++] = char_array_3[j];
	}
	(*data)[*length] = '\0';
	return true;
}