base64.cpp

00001 
00002 /*
00003 Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
00004  
00005 Permission is hereby granted, free of charge, to any person obtaining a copy
00006 of this software and associated documentation files (the "Software"), to deal
00007 in the Software without restriction, including without limitation the rights
00008 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00009 copies of the Software, and to permit persons to whom the Software is
00010 furnished to do so, subject to the following conditions:
00011  
00012 The above copyright notice and this permission notice shall be included in
00013 all copies or substantial portions of the Software.
00014  
00015 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00016 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00017 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00018 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00019 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00020 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
00021 THE SOFTWARE.
00022 */
00023 
00024 #include "base64.h"
00025 //Originaly from Rolf's iputil.c
00026 
00027 #ifdef __cplusplus
00028 extern "C" {
00029 #endif
00030 
00031 #include <string.h>
00032 
00033 unsigned int base64enc_len(const char *str) {
00034   return (((strlen(str)-1)/3)+1)<<2;
00035 }
00036 
00037 void base64enc(const char *input, unsigned int length, char *output) {
00038   static const char base64[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
00039   unsigned int c, c1, c2, c3;
00040   for(unsigned int i = 0, j = 0; i<length; i+=3,j+=4) {
00041     c1 = ((((unsigned char)*((unsigned char *)&input[i]))));
00042     c2 = (length>i+1)?((((unsigned char)*((unsigned char *)&input[i+1])))):0;
00043     c3 = (length>i+2)?((((unsigned char)*((unsigned char *)&input[i+2])))):0;
00044 
00045     c = ((c1 & 0xFC) >> 2);
00046     output[j+0] = base64[c];
00047     c = ((c1 & 0x03) << 4) | ((c2 & 0xF0) >> 4);
00048     output[j+1] = base64[c];
00049     c = ((c2 & 0x0F) << 2) | ((c3 & 0xC0) >> 6);
00050     output[j+2] = (length>i+1)?base64[c]:'=';
00051     c = (c3 & 0x3F);
00052     output[j+3] = (length>i+2)?base64[c]:'=';
00053   }
00054   output[(((length-1)/3)+1)<<2] = '\0';
00055 }
00056 
00057 #ifdef __cplusplus
00058 }
00059 #endif
00060