winamp/Src/Plugins/DSP/sc_serv3/base64.cpp

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2024-09-24 12:54:57 +00:00
#include <vector>
#include "base64.h"
using namespace std;
static const std::string base64_chars =
"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
"abcdefghijklmnopqrstuvwxyz"
"0123456789+/";
static inline bool is_base64(__uint8 c)
{
return (isalnum(c) || (c == '+') || (c == '/'));
}
const std::vector<__uint8> base64::decode(std::string const& encoded_string)
{
size_t in_len = encoded_string.size();
int i = 0, in_ = 0;
__uint8 char_array_4[4], char_array_3[3];
std::vector<__uint8> ret;
while (in_len-- && ( encoded_string[in_] != '=') && is_base64(encoded_string[in_]))
{
char_array_4[i++] = encoded_string[in_]; ++in_;
if (i == 4)
{
for (i = 0; i <4; i++)
{
char_array_4[i] = (__uint8)base64_chars.find(char_array_4[i]);
}
char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];
for (i = 0; (i < 3); i++)
{
ret.push_back(char_array_3[i]);
}
i = 0;
}
}
if (i)
{
int j = 0;
for (j = i; j <4; j++)
{
char_array_4[j] = 0;
}
for (j = 0; j <4; j++)
{
char_array_4[j] = (__uint8)base64_chars.find(char_array_4[j]);
}
char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];
for (j = 0; (j < i - 1); j++)
{
ret.push_back(char_array_3[j]);
}
}
return ret;
}