SnBase64.cpp

00001 #if 0 
00002 /*
00003 #include "SnBase64.h"
00004 
00005 #include "SnBase64data.h"
00006 
00007 /**
00008  * \file modp_b64.c
00009  * <PRE>
00010  * MODP_B64 - High performance base64 encoder/decoder
00011  * http://code.google.com/p/stringencoders/
00012  *
00013  * Copyright &copy; 2005, 2006, 2007  Nick Galbreath -- nickg [at] modp [dot] com
00014  * All rights reserved.
00015  *
00016  * Redistribution and use in source and binary forms, with or without
00017  * modification, are permitted provided that the following conditions are
00018  * met:
00019  *
00020  *   Redistributions of source code must retain the above copyright
00021  *   notice, this list of conditions and the following disclaimer.
00022  *
00023  *   Redistributions in binary form must reproduce the above copyright
00024  *   notice, this list of conditions and the following disclaimer in the
00025  *   documentation and/or other materials provided with the distribution.
00026  *
00027  *   Neither the name of the modp.com nor the names of its
00028  *   contributors may be used to endorse or promote products derived from
00029  *   this software without specific prior written permission.
00030  *
00031  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
00032  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
00033  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
00034  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
00035  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
00036  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
00037  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
00038  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
00039  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
00040  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
00041  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
00042  *
00043  * This is the standard "new" BSD license:
00044  * http://www.opensource.org/licenses/bsd-license.php
00045  * </PRE>
00046  */
00047 
00048 #define BADCHAR 0x01FFFFFF
00049 
00050 /**
00051  * you can control if we use padding by commenting out this
00052  * next line.  However, I highly recommend you use padding and not
00053  * using it should only be for compatability with a 3rd party.
00054  * Also, 'no padding' is not tested!
00055  */
00056 #define DOPAD 1
00057 
00058 /*
00059  * if we aren't doing padding
00060  * set the pad character to NULL
00061  */
00062 #ifndef DOPAD
00063 #undef CHARPAD
00064 #define CHARPAD '\0'
00065 #endif
00066 
00067 int B64::modp_b64_encode(const char* str, const int len, char* dest)
00068 {
00069     int i;
00070     const uint8_t* s = (const uint8_t*) str;
00071     uint8_t* p = (uint8_t*) dest;
00072 
00073     /* unsigned here is important! */
00074     /* uint8_t is fastest on G4, amd */
00075     /* uint32_t is fastest on Intel */
00076     uint32_t t1, t2, t3;
00077     
00078     for (i = 0; i < len - 2; i += 3) {
00079         t1 = s[i]; t2 = s[i+1]; t3 = s[i+2];
00080         *p++ = e0[t1];
00081         *p++ = e1[((t1 & 0x03) << 4) | ((t2 >> 4) & 0x0F)];
00082         *p++ = e1[((t2 & 0x0F) << 2) | ((t3 >> 6) & 0x03)];
00083         *p++ = e2[t3];
00084     }
00085 
00086     switch (len - i) {
00087     case 0:
00088         break;
00089     case 1:
00090         t1 = s[i];
00091         *p++ = e0[t1];
00092         *p++ = e1[(t1 & 0x03) << 4];
00093         *p++ = CHARPAD;
00094         *p++ = CHARPAD;
00095         break;
00096     default: /* case 2 */
00097         t1 = s[i]; t2 = s[i+1];
00098         *p++ = e0[t1];
00099         *p++ = e1[((t1 & 0x03) << 4) | ((t2 >> 4) & 0x0F)];
00100         *p++ = e2[(t2 & 0x0F) << 2];
00101         *p++ = CHARPAD;
00102     }
00103 
00104     *p = '\0';
00105     return (int)(p - (uint8_t*)dest);
00106 }
00107 
00108 int B64::modp_b64_decode(const char* src, int len, char* dest)
00109 {
00110     int i;
00111     if (len == 0) return 0;
00112 
00113 #ifdef DOPAD
00114     /*
00115      * if padding is used, then the message must be at least
00116      * 4 chars and be a multiple of 4
00117      */
00118     if (len < 4 || (len % 4 != 0)) return -1; /* error */
00119     /* there can be at most 2 pad chars at the end */
00120     if (src[len-1] == CHARPAD) {
00121         len--;
00122         if (src[len -1] == CHARPAD) {
00123             len--;
00124         }
00125     }
00126 #endif
00127 
00128     int leftover = len % 4;
00129     int chunks = (leftover == 0) ? len / 4 - 1 : len /4;
00130 
00131     uint8_t* p = (uint8_t*) dest;
00132     uint32_t x = 0;
00133     uint32_t* destInt = (uint32_t*) p;
00134     uint32_t* srcInt = (uint32_t*) src;
00135     uint32_t y = *srcInt++;
00136     for (i = 0; i < chunks; ++i) {
00137         x = d0[y & 0xff] |
00138             d1[(y >> 8) & 0xff] |
00139             d2[(y >> 16) & 0xff] |
00140             d3[(y >> 24) & 0xff];
00141 
00142         if (x >= BADCHAR) return -1;
00143         *destInt = x ;
00144         p += 3;
00145         destInt = (uint32_t*)p;
00146         y = *srcInt++;}
00147 
00148 
00149     switch (leftover) {
00150     case 0:
00151         x = d0[y & 0xff] |
00152             d1[(y >> 8) & 0xff] |
00153             d2[(y >> 16) & 0xff] |
00154             d3[(y >> 24) & 0xff];
00155 
00156         if (x >= BADCHAR) return -1;
00157         *p++ =  ((uint8_t*)(&x))[0];
00158         *p++ =  ((uint8_t*)(&x))[1];
00159         *p =    ((uint8_t*)(&x))[2];
00160         return (chunks+1)*3;
00161         //break;
00162 #ifndef DOPAD
00163     case 1:  /* with padding this is an impossible case */
00164         x = d0[y & 0xff];
00165         *p = *((uint8_t*)(&x)); // i.e. first char/byte in int
00166         break;
00167 #endif
00168     case 2: // * case 2, 1  output byte */
00169         x = d0[y & 0xff] | d1[y >> 8 & 0xff];
00170         *p = *((uint8_t*)(&x)); // i.e. first char
00171         break;
00172     default: /* case 3, 2 output bytes */
00173         x = d0[y & 0xff] |
00174             d1[y >> 8 & 0xff ] |
00175             d2[y >> 16 & 0xff];  /* 0x3c */
00176         *p++ =  ((uint8_t*)(&x))[0];
00177         *p =  ((uint8_t*)(&x))[1];
00178         break;
00179     }
00180 
00181     if (x >= BADCHAR) return -1;
00182 
00183     return 3*chunks + (6*leftover)/8;
00184 }
00185 */
00186 #endif