Disk ARchive
2.4.5
|
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 : dar.linux@free.fr 00020 /*********************************************************************/ 00021 // $Id$ 00022 // 00023 /*********************************************************************/ 00024 00025 #ifndef COMPRESSOR_HPP 00026 #define COMPRESSOR_HPP 00027 00028 #pragma interface 00029 00030 #include "generic_file.hpp" 00031 #include "integers.hpp" 00032 #include "wrapperlib.hpp" 00033 00034 enum compression { none = 'n', zip = 'p', gzip = 'z', bzip2 = 'y' }; 00035 00036 extern compression char2compression(char a); 00037 extern char compression2char(compression c); 00038 extern string compression2string(compression c); 00039 00040 class compressor : public generic_file 00041 { 00042 public : 00043 compressor(compression algo, generic_file & compressed_side, U_I compression_level = 9); 00044 // compressed_side is not owned by the object and will remains 00045 // after the objet destruction 00046 compressor(compression algo, generic_file *compressed_side, U_I compression_level = 9); 00047 // compressed_side is owned by the object and will be 00048 // deleted a destructor time 00049 ~compressor(); 00050 00051 void flush_write(); // flush all data to compressed_side, and reset the compressor 00052 // for that additional write can be uncompresssed starting at this point. 00053 void flush_read(); // reset decompression engine to be able to read the next block of compressed data 00054 // if not called, furthur read return EOF 00055 void clean_read(); // discard any byte buffered and not yet returned by read() 00056 void clean_write(); // discard any byte buffered and not yet wrote to compressed_side; 00057 00058 compression get_algo() const { return current_algo; }; 00059 void change_algo(compression new_algo, U_I new_compression_level = 9); 00060 00061 // inherited from generic file 00062 bool skip(const infinint & position) { flush_write(); flush_read(); clean_read(); return compressed->skip(position); }; 00063 bool skip_to_eof() { flush_write(); flush_read(); clean_read(); return compressed->skip_to_eof(); }; 00064 bool skip_relative(S_I x) { flush_write(); flush_read(); clean_read(); return compressed->skip_relative(x); }; 00065 infinint get_position() { return compressed->get_position(); }; 00066 00067 protected : 00068 S_I inherited_read(char *a, size_t size) { return (this->*read_ptr)(a, size); }; 00069 S_I inherited_write(char *a, size_t size) { return (this->*write_ptr)(a, size); }; 00070 00071 private : 00072 struct xfer 00073 { 00074 wrapperlib wrap; 00075 char *buffer; 00076 U_I size; 00077 00078 xfer(U_I sz, wrapperlib_mode mode); 00079 ~xfer(); 00080 }; 00081 00082 xfer *compr, *decompr; 00083 generic_file *compressed; 00084 bool compressed_owner; 00085 compression current_algo; 00086 00087 void init(compression algo, generic_file *compressed_side, U_I compression_level); 00088 void terminate(); 00089 S_I (compressor::*read_ptr) (char *a, size_t size); 00090 S_I none_read(char *a, size_t size); 00091 S_I gzip_read(char *a, size_t size); 00092 // S_I zip_read(char *a, size_t size); 00093 // S_I bzip2_read(char *a, size_t size); // using gzip_read, same code thanks to wrapperlib 00094 00095 S_I (compressor::*write_ptr) (char *a, size_t size); 00096 S_I none_write(char *a, size_t size); 00097 S_I gzip_write(char *a, size_t size); 00098 // S_I zip_write(char *a, size_t size); 00099 // S_I bzip2_write(char *a, size_t size); // using gzip_write, same code thanks to wrapperlib 00100 }; 00101 00102 #endif