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Disk ARchive
2.5.2
Full featured and portable backup and archiving tool
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00001 /*********************************************************************/ 00002 // dar - disk archive - a backup/restoration program 00003 // Copyright (C) 2002-2052 Denis Corbin 00004 // 00005 // This program is free software; you can redistribute it and/or 00006 // modify it under the terms of the GNU General Public License 00007 // as published by the Free Software Foundation; either version 2 00008 // of the License, or (at your option) any later version. 00009 // 00010 // This program is distributed in the hope that it will be useful, 00011 // but WITHOUT ANY WARRANTY; without even the implied warranty of 00012 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00013 // GNU General Public License for more details. 00014 // 00015 // You should have received a copy of the GNU General Public License 00016 // along with this program; if not, write to the Free Software 00017 // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 00018 // 00019 // to contact the author : http://dar.linux.free.fr/email.html 00020 /*********************************************************************/ 00021 00025 00026 #ifndef CRC_HPP 00027 #define CRC_HPP 00028 00029 #include "../my_config.h" 00030 00031 #include <string> 00032 #include <list> 00033 #include "integers.hpp" 00034 #include "storage.hpp" 00035 #include "infinint.hpp" 00036 #include "on_pool.hpp" 00037 00038 namespace libdar 00039 { 00040 00043 00044 class crc : public on_pool 00045 { 00046 public: 00047 static const U_I OLD_CRC_SIZE = 2; 00048 00049 virtual ~crc() throw(Ebug) {}; 00050 00051 virtual bool operator == (const crc & ref) const = 0; 00052 bool operator != (const crc & ref) const { return ! (*this == ref); }; 00053 00054 virtual void compute(const infinint & offset, const char *buffer, U_I length) = 0; 00055 virtual void compute(const char *buffer, U_I length) = 0; // for sequential read only 00056 virtual void clear() = 0; 00057 virtual void dump(generic_file & f) const = 0; 00058 virtual std::string crc2str() const = 0; 00059 virtual infinint get_size() const = 0; 00060 virtual crc *clone() const = 0; 00061 }; 00062 00063 extern crc *create_crc_from_file(generic_file & f, memory_pool *pool, bool old = false); 00064 extern crc *create_crc_from_size(infinint width, memory_pool *pool); 00065 00066 class crc_i : public crc 00067 { 00068 public: 00069 crc_i(const infinint & width); 00070 crc_i(const infinint & width, generic_file & f); 00071 crc_i(const crc_i & ref) : size(ref.size), cyclic(ref.size) { copy_data_from(ref); pointer = cyclic.begin(); }; 00072 const crc_i & operator = (const crc_i & ref) { copy_from(ref); return *this; }; 00073 00074 bool operator == (const crc & ref) const; 00075 00076 void compute(const infinint & offset, const char *buffer, U_I length); 00077 void compute(const char *buffer, U_I length); // for sequential read only 00078 void clear(); 00079 void dump(generic_file & f) const; 00080 std::string crc2str() const; 00081 infinint get_size() const { return size; }; 00082 00083 protected: 00084 crc *clone() const { return new (get_pool()) crc_i(*this); }; 00085 00086 private: 00087 00088 infinint size; //< size of the checksum 00089 storage::iterator pointer; //< points to the next byte to modify 00090 storage cyclic; //< the checksum storage 00091 00092 void copy_from(const crc_i & ref); 00093 void copy_data_from(const crc_i & ref); 00094 }; 00095 00096 00097 class crc_n : public crc 00098 { 00099 public: 00100 00101 crc_n(U_I width); 00102 crc_n(U_I width, generic_file & f); 00103 crc_n(const crc_n & ref) { copy_from(ref); }; 00104 const crc_n & operator = (const crc_n & ref); 00105 ~crc_n() { destroy(); }; 00106 00107 bool operator == (const crc & ref) const; 00108 00109 void compute(const infinint & offset, const char *buffer, U_I length); 00110 void compute(const char *buffer, U_I length); // for sequential read only 00111 void clear(); 00112 void dump(generic_file & f) const; 00113 std::string crc2str() const; 00114 infinint get_size() const { return size; }; 00115 00116 protected: 00117 crc *clone() const { return new (get_pool()) crc_n(*this); }; 00118 00119 private: 00120 00121 U_I size; //< size of checksum (non infinint mode) 00122 unsigned char *pointer; //< points to the next byte to modify (non infinint mode) 00123 unsigned char *cyclic; //< the checksum storage (non infinint mode) 00124 00125 void alloc(U_I width); 00126 void copy_from(const crc_n & ref); 00127 void copy_data_from(const crc_n & ref); 00128 void destroy(); 00129 }; 00130 00131 00133 00134 } // end of namespace 00135 00136 00137 #endif