bb64/b64ed.cpp
Your Name bb355cf4ac Tidy
2025-05-12 19:48:56 +12:00

42 lines
1.1 KiB
C++

#include "b64ed.hpp"
#include <vector>
// Custom base64 encoding/decoding tables
static const std::string custom_base64_chars =
"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
"abcdefghijklmnopqrstuvwxyz"
"0123456789+_";
std::string base64_encode(const std::string &in) {
std::string out;
int val = 0, valb = -6;
for (unsigned char c : in) {
val = (val << 8) + c;
valb += 8;
while (valb >= 0) {
out.push_back(custom_base64_chars[(val >> valb) & 0x3F]);
valb -= 6;
}
}
if (valb > -6) out.push_back(custom_base64_chars[((val << 8) >> (valb + 8)) & 0x3F]);
while (out.size() % 4) out.push_back('=');
return out;
}
std::string base64_decode(const std::string &in) {
std::vector<int> T(256, -1);
for (int i = 0; i < 64; i++) T[custom_base64_chars[i]] = i;
std::string out;
int val = 0, valb = -8;
for (unsigned char c : in) {
if (T[c] == -1) break;
val = (val << 6) + T[c];
valb += 6;
if (valb >= 0) {
out.push_back(char((val >> valb) & 0xFF));
valb -= 8;
}
}
return out;
}