base64

#ifndef _BASE64_H_#define _BASE64_H_#include <string>std::string base64_encode(unsigned char const* , unsigned int len);std::string base64_decode(std::string const& s);#endif// base64.cpp#include "stdafx.h"#include "base64.h"static const std::string base64_chars =     "ABCDEFGHIJKLMNOPQRSTUVWXYZ"    "abcdefghijklmnopqrstuvwxyz"    "0123456789+/";static inline bool is_base64(unsigned char c) {    return (isalnum(c) || (c == '+') || (c == '/'));}std::string base64_encode(unsigned char const* bytes_to_encode, unsigned int in_len) {    std::string ret;    int i = 0;    int j = 0;    unsigned char char_array_3[3];    unsigned char char_array_4[4];    while (in_len--) {        char_array_3[i++] = *(bytes_to_encode++);        if (i == 3) {            char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;            char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);            char_array_4[2] = ((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++)                ret += 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] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);        char_array_4[2] = ((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++)            ret += base64_chars[char_array_4[j]];        while((i++ < 3))            ret += '=';    }    return ret;}std::string base64_decode(std::string const& encoded_string) {    size_t in_len = encoded_string.size();    size_t i = 0;    size_t j = 0;    int in_ = 0;    unsigned char char_array_4[4], char_array_3[3];    std::string 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] = static_cast<unsigned char>(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 += char_array_3[i];            i = 0;        }    }    if (i) {        for (j = i; j <4; j++)            char_array_4[j] = 0;        for (j = 0; j <4; j++)            char_array_4[j] = static_cast<unsigned char>(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 += char_array_3[j];    }    return ret;}