base64 encode decode

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base64.h

#include <string>#ifndef _BASE64_H_#define _BASE64_H_std::string base64_encode(unsigned char const* , unsigned int len);std::string base64_decode(std::string const& s);#endif

base64.cpp

/*    base64.cpp and base64.h   Copyright (C) 2004-2008 Ren Nyffenegger rene.nyffenegger@adp-gmbh.ch */ #include "base64.h" #include <iostream> 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, j = 0;  unsigned char char_array_3[3], 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)  {  int in_len = encoded_string.size();  int i = 0, j = 0, 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] = 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] = 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; }

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