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_chars.hat(base64[l])) 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) && n < *length; 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) && n < *length; j++)
            (*data)[n++] = char_array_3[j];
    }
    (*data)[*length] = '\0';
    return true;
}