/Users/kmartin/Documents/files/code/cpp/OScpp/COIN-OS/OS/src/OSUtils/OSBase64.cpp

Go to the documentation of this file.

#include "OSBase64.h"
#include <sstream>  


static const std::string base64_chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
             "abcdefghijklmnopqrstuvwxyz"
             "0123456789+/";

std::string Base64::encodeb64(char* bytes, int string_size){
        unsigned char out_byte1, out_byte2, out_byte3, out_byte4;
        unsigned char in_byte1, in_byte2, in_byte3;
        std::ostringstream outStr;
        int remainder = string_size%3;
        // get a number divisible by 3
        int test = string_size - remainder;
        while(test > 0){
                in_byte1 = *(bytes++);
                in_byte2 = *(bytes++);
                in_byte3 = *(bytes++);
                out_byte1 = (in_byte1 >> 2);
                out_byte2 = (in_byte1 & 0x03) << 4 | (in_byte2 >> 4);
                out_byte3 = (in_byte2 & 0x0f) << 2 | (in_byte3 >> 6);
                out_byte4 = in_byte3 & 0x3f;
                outStr << base64_chars[out_byte1];
                outStr <<  base64_chars[out_byte2];  
                outStr << base64_chars[out_byte3];
                outStr << base64_chars[out_byte4]  ;
                test = test - 3;
        } 
        // now take care of padding
        if(remainder > 0){
                in_byte1 = *(bytes++);
                in_byte3 = '\0';
                out_byte1 = (in_byte1 >> 2);
                outStr << base64_chars[out_byte1];
                if(remainder == 1){
                        in_byte2 = '\0';
                        out_byte2 = (in_byte1 & 0x03) << 4 | (in_byte2 >> 4);
                        outStr <<  base64_chars[out_byte2];  
                        outStr << '=';
                }
                else{
                        in_byte2 = *(bytes++);
                        out_byte2 = (in_byte1 & 0x03) << 4 | (in_byte2 >> 4);
                        out_byte3 = (in_byte2 & 0x0f) << 2 | (in_byte3 >> 6);
                        outStr <<  base64_chars[out_byte2];  
                        outStr << base64_chars[out_byte3];
                }
                outStr << '=';
        }
        return outStr.str();

}//encodeb64

std::string Base64::decodeb64(char* b64bytes){
        unsigned char out_byte1, out_byte2, out_byte3;
        unsigned char in_byte1, in_byte2, in_byte3, in_byte4;
        std::ostringstream outStr;
        // first take of the non-padded bytes
        while(*b64bytes != '=' && *b64bytes != '\0'){
                in_byte1 = base64_chars.find(*(b64bytes++));
                in_byte2 = base64_chars.find(*(b64bytes++));
                in_byte3 = base64_chars.find(*(b64bytes++));
                in_byte4 = base64_chars.find(*(b64bytes++));
                out_byte1 = (in_byte1 << 2)  | ((in_byte2 & 0x30)  >> 4)  ;
                out_byte2 = ((in_byte2 & 0x0f) << 4)  | ((in_byte3 & 0x3c)  >> 2)  ;
                out_byte3 = ((in_byte3  & 0x03) << 6)  |  in_byte4  ;
                outStr << out_byte1;
                outStr << out_byte2;  
                outStr << out_byte3;
        } 
        // now take into account the padding
        if(*b64bytes == '='){
                in_byte1 = base64_chars.find(*(b64bytes++));
                in_byte2 = base64_chars.find(*(b64bytes++));
                in_byte4 = '\0';
                out_byte1 = (in_byte1 << 2)  | ((in_byte2 & 0x30)  >> 4)  ;
                outStr << out_byte1;
                *b64bytes++;
                if(*b64bytes == '\0'){ //if null we had only one = in the padding
                        in_byte3 = base64_chars.find(*(b64bytes++));
                        out_byte2 = ((in_byte2 & 0x0f) << 4)  | ((in_byte3 & 0x3c)  >> 2)  ;
                        out_byte3 = ((in_byte3  & 0x03) << 6)  |  in_byte4  ;
                        outStr << out_byte2;  
                }
                else{ // we have == in the padding
                        in_byte3 = '\0';
                        out_byte2 = ((in_byte2 & 0x0f) << 4)  | ((in_byte3 & 0x3c)  >> 2)  ;
                        out_byte3 = ((in_byte3  & 0x03) << 6)  |  in_byte4  ;
                        //outStr << out_byte2;  
                        //outStr << out_byte3;
                }
        }
        return outStr.str();
} // decodeb64

---