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File: [Pegasus] / pegasus / src / Pegasus / Common / Base64.cpp
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Revision: 1.4, Thu Feb 7 20:02:02 2002 UTC (22 years, 4 months ago) by kumpf Branch: MAIN CVS Tags: pre-meta-dispatcher Changes since 1.3: +2 -2 lines HP-RK Remove 'inline' designation from methods. |
//%///////////////////////////////////////////////////////////////////////////// // // Copyright (c) 2000, 2001 BMC Software, Hewlett-Packard Company, IBM, // The Open Group, Tivoli Systems // // Permission is hereby granted, free of charge, to any person obtaining a copy // of this software and associated documentation files (the "Software"), to // deal in the Software without restriction, including without limitation the // rights to use, copy, modify, merge, publish, distribute, sublicense, and/or // sell copies of the Software, and to permit persons to whom the Software is // furnished to do so, subject to the following conditions: // // THE ABOVE COPYRIGHT NOTICE AND THIS PERMISSION NOTICE SHALL BE INCLUDED IN // ALL COPIES OR SUBSTANTIAL PORTIONS OF THE SOFTWARE. THE SOFTWARE IS PROVIDED // "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT // LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR // PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT // HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN // ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. // //============================================================================== // // Author: Karl Schopmeyer (k.schopmeyer@opengroup.org) // // Modified By: // //%///////////////////////////////////////////////////////////////////////////// #include "Base64.h" #include <cassert> #include <strstream> #include <string> #include <Pegasus/Common/String.h> #include <Pegasus/Common/Base64.h> #include <Pegasus/Common/Array.h> PEGASUS_NAMESPACE_BEGIN PEGASUS_USING_STD; //************************************************************* /* Encode static method takes an array of 8-bit values and returns a base-64 stream. ATTN: KS feb 2002 - This is probably a very slow an inefficient implementation and could be improved if it is required for production. Today it is only for test programs. */ Array<Sint8> Base64::encode(const Array<Uint8>& vby) { Array<Sint8> retArray; // If nothing in input string, return empty string if (vby.size() == 0) return retArray; // for every character in the input array taken 3 bytes at a time for (Uint32 i=0; i < vby.size(); i+=3) { // Create from 3 8 bit values to 4 6 bit values Uint8 by1=0,by2=0,by3=0; by1 = vby[i]; if (i+1<vby.size()) { by2 = vby[i+1]; }; if (i+2<vby.size()) { by3 = vby[i+2]; } Uint8 by4=0,by5=0,by6=0,by7=0; by4 = by1>>2; by5 = ((by1&0x3)<<4)|(by2>>4); by6 = ((by2&0xf)<<2)|(by3>>6); by7 = by3&0x3f; retArray.append(_Encode(by4)); retArray.append(_Encode(by5)); if (i+1<vby.size()) retArray.append( _Encode(by6)); else retArray.append('='); if (i+2<vby.size()) retArray.append( _Encode(by7)); else retArray.append('='); if (i % (76/4*3) == 0) { retArray.append( '\r'); retArray.append( '\n'); } }; return retArray; }; /*I checked for the zero length. The algorithm would also work for zero length input stream, but I’m pretty adamant about handling border conditions. They are often the culprits of run-time production failures. The algorithm goes thru each three bytes of data at a time. The first thing I do is to shift the bits around from three 8-bit values to four 6-bit values. Then I encode the 6-bit values and add then one at a time to the output stream. This is actually quite inefficient. The STL character array is being allocated one byte at a time. The algorithm would be much faster, if I pre-allocated that array. I’ll leave that as an optimization practical exercise for the reader. /* The decode static method takes a base-64 stream and converts it to an array of 8-bit values. */ Array<Uint8> Base64::decode(const Array<Sint8> strInput) { //Strip any non-base64 characters from the input PEGASUS_STD(string) str; for (Uint32 j=0;j<strInput.size();j++) { if (_IsBase64(strInput[j])) str += strInput[j]; } Array<Uint8> retArray; // Return if the input is zero length if (str.length() == 0) return retArray; // comment for (int i=0; i < str.length();i+=4) { char c1='A',c2='A',c3='A',c4='A'; c1 = str[i]; if (i+1<str.length()) c2 = str[i+1]; if (i+2<str.length()) c3 = str[i+2]; if (i+3<str.length()) c4 = str[i+3]; Uint8 by1=0,by2=0,by3=0,by4=0; by1 = _Decode(c1); by2 = _Decode(c2); by3 = _Decode(c3); by4 = _Decode(c4); //cout << "base::64decode bytes" << // " 1 " << c1 << " " << by1 << // " 2 " << c2 << " " << by2 << // " 3 " << c3 << " " << by3 << // " 4 " << c4 << " " << by4 << endl; // append first byte by shifting retArray.append( (by1<<2)|(by2>>4) ); // append second byte if not padding if (c3 != '=') retArray.append( ((by2&0xf)<<4)|(by3>>2) ); if (c4 != '=') retArray.append( ((by3&0x3)<<6)|by4 ); } return retArray; }; //********************************************************** /* Encode thanslates one six-bit pattern into a base-64 character. Unsigned char is used to represent a six-bit stream of date. */ inline PEGASUS_COMMON_LINKAGE char Base64::_Encode(Uint8 uc) { if (uc < 26) return 'A'+uc; if (uc < 52) return 'a'+(uc-26); if (uc < 62) return '0'+(uc-52); if (uc == 62) return '+'; return '/'; }; //Helper function returns true is a character is a valid base-64 character and false otherwise. inline Boolean Base64::_IsBase64(char c) { if (c >= 'A' && c <= 'Z') return true; if (c >= 'a' && c <= 'z') return true; if (c >= '0' && c <= '9') return true; if (c == '+') return true; if (c == '/') return true; if (c == '=') return true; return false; }; // Translate one base-64 character into a six bit pattern inline Uint8 Base64::_Decode(char c) { if (c >= 'A' && c <= 'Z') return c - 'A'; if (c >= 'a' && c <= 'z') return c - 'a' + 26; if (c >= '0' && c <= '9') return c - '0' + 52; if (c == '+') return 62; return 63; }; PEGASUS_NAMESPACE_END
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