Disk ARchive
2.4.5
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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 // $Id$ 00022 // 00023 /*********************************************************************/ 00024 00031 00032 #ifndef TRONC_HPP 00033 #define TRONC_HPP 00034 00035 #include "../my_config.h" 00036 #include "infinint.hpp" 00037 #include "generic_file.hpp" 00038 00039 namespace libdar 00040 { 00043 00045 00046 class tronc : public generic_file 00047 { 00048 public : 00050 00055 tronc(generic_file *f, const infinint &offset, const infinint &size, bool own_f = false); 00056 tronc(generic_file *f, const infinint &offset, const infinint &size, gf_mode mode, bool own_f = false); 00057 00060 tronc(generic_file *f, const infinint &offset, bool own_f = false); 00061 tronc(generic_file *f, const infinint &offset, gf_mode mode, bool own_f = false); 00062 00064 ~tronc() 00065 { 00066 if(own_ref) 00067 delete ref; 00068 }; 00069 00071 bool skip(const infinint & pos); 00073 bool skip_to_eof(); 00075 bool skip_relative(S_I x); 00077 infinint get_position() { return current; }; 00078 00079 #ifdef LIBDAR_SPECIAL_ALLOC 00080 USE_SPECIAL_ALLOC(tronc); 00081 #endif 00082 protected : 00084 U_I inherited_read(char *a, U_I size); 00086 void inherited_write(const char *a, U_I size); 00087 void inherited_sync_write() { ref->sync_write(); } 00088 void inherited_terminate() {if(own_ref) ref->terminate(); }; 00089 00090 private : 00091 infinint start; //< offset in the global generic file to start at 00092 infinint sz; //< length of the portion to consider 00093 generic_file *ref; //< global generic file of which to take a piece 00094 infinint current; //< inside position of the next read or write 00095 bool own_ref; //< whether we own ref (and must destroy it when no more needed) 00096 bool limited; //< whether the sz argument is to be considered 00097 00098 void set_back_current_position(); 00099 }; 00100 00102 00103 } // end of namespace 00104 00105 #endif