| 1 | tim | 615 | // ============================================================================ | 
| 2 |  |  | // gzstream, C++ iostream classes wrapping the zlib compression library. | 
| 3 |  |  | // Copyright (C) 2001  Deepak Bandyopadhyay, Lutz Kettner | 
| 4 |  |  | // | 
| 5 |  |  | // This library is free software; you can redistribute it and/or | 
| 6 |  |  | // modify it under the terms of the GNU Lesser General Public | 
| 7 |  |  | // License as published by the Free Software Foundation; either | 
| 8 |  |  | // version 2.1 of the License, or (at your option) any later version. | 
| 9 |  |  | // | 
| 10 |  |  | // This library is distributed in the hope that it will be useful, | 
| 11 |  |  | // but WITHOUT ANY WARRANTY; without even the implied warranty of | 
| 12 |  |  | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU | 
| 13 |  |  | // Lesser General Public License for more details. | 
| 14 |  |  | // | 
| 15 |  |  | // You should have received a copy of the GNU Lesser General Public | 
| 16 |  |  | // License along with this library; if not, write to the Free Software | 
| 17 |  |  | // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA | 
| 18 |  |  | // ============================================================================ | 
| 19 |  |  | // | 
| 20 |  |  | // File          : gzstream.h | 
| 21 |  |  | // Revision      : $Revision: 1.1 $ | 
| 22 |  |  | // Revision_date : $Date: 2005-09-20 21:22:38 $ | 
| 23 |  |  | // Author(s)     : Deepak Bandyopadhyay, Lutz Kettner | 
| 24 |  |  | // | 
| 25 |  |  | // Standard streambuf implementation following Nicolai Josuttis, "The | 
| 26 |  |  | // Standard C++ Library". | 
| 27 |  |  | // ============================================================================ | 
| 28 |  |  |  | 
| 29 |  |  | #ifndef IO_GZSTREAM_HPP | 
| 30 |  |  | #define IO_GZSTREAM_HPP | 
| 31 |  |  |  | 
| 32 |  |  | // standard C++ with new header file names and std:: namespace | 
| 33 |  |  | #include <iostream> | 
| 34 |  |  | #include <fstream> | 
| 35 |  |  | #include <zlib.h> | 
| 36 |  |  |  | 
| 37 |  |  | namespace oopse { | 
| 38 |  |  |  | 
| 39 |  |  |  | 
| 40 |  |  | // ---------------------------------------------------------------------------- | 
| 41 |  |  | // Internal classes to implement gzstream. See below for user classes. | 
| 42 |  |  | // ---------------------------------------------------------------------------- | 
| 43 |  |  |  | 
| 44 |  |  | class gzstreambuf : public std::streambuf { | 
| 45 |  |  | private: | 
| 46 |  |  | static const int bufferSize = 47+256;    // size of data buff | 
| 47 |  |  | // totals 512 bytes under g++ for igzstream at the end. | 
| 48 |  |  |  | 
| 49 |  |  | gzFile           file;               // file handle for compressed file | 
| 50 |  |  | char             buffer[bufferSize]; // data buffer | 
| 51 |  |  | char             opened;             // open/close state of stream | 
| 52 |  |  | int              mode;               // I/O mode | 
| 53 |  |  |  | 
| 54 |  |  | int flush_buffer(); | 
| 55 |  |  | public: | 
| 56 |  |  | gzstreambuf() : opened(0) { | 
| 57 |  |  | setp( buffer, buffer + (bufferSize-1)); | 
| 58 |  |  | setg( buffer + 4,     // beginning of putback area | 
| 59 |  |  | buffer + 4,     // read position | 
| 60 |  |  | buffer + 4);    // end position | 
| 61 |  |  | // ASSERT: both input & output capabilities will not be used together | 
| 62 |  |  | } | 
| 63 |  |  | int is_open() { return opened; } | 
| 64 |  |  | gzstreambuf* open( const char* name, int open_mode); | 
| 65 |  |  | gzstreambuf* close(); | 
| 66 |  |  | ~gzstreambuf() { close(); } | 
| 67 |  |  |  | 
| 68 |  |  | virtual int     overflow( int c = EOF); | 
| 69 |  |  | virtual int     underflow(); | 
| 70 |  |  | virtual int     sync(); | 
| 71 |  |  | }; | 
| 72 |  |  |  | 
| 73 |  |  | class gzstreambase : virtual public std::ios { | 
| 74 |  |  | protected: | 
| 75 |  |  | gzstreambuf buf; | 
| 76 |  |  | public: | 
| 77 |  |  | gzstreambase() { init(&buf); } | 
| 78 |  |  | gzstreambase( const char* name, int open_mode); | 
| 79 |  |  | ~gzstreambase(); | 
| 80 |  |  | void open( const char* name, int open_mode); | 
| 81 |  |  | void close(); | 
| 82 |  |  | gzstreambuf* rdbuf() { return &buf; } | 
| 83 |  |  | }; | 
| 84 |  |  |  | 
| 85 |  |  | // ---------------------------------------------------------------------------- | 
| 86 |  |  | // User classes. Use igzstream and ogzstream analogously to ifstream and | 
| 87 |  |  | // ofstream respectively. They read and write files based on the gz* | 
| 88 |  |  | // function interface of the zlib. Files are compatible with gzip compression. | 
| 89 |  |  | // ---------------------------------------------------------------------------- | 
| 90 |  |  |  | 
| 91 |  |  | class igzstream : public gzstreambase, public std::istream { | 
| 92 |  |  | public: | 
| 93 |  |  | igzstream() : std::istream( &buf) {} | 
| 94 |  |  | igzstream( const char* name, int open_mode = std::ios::in) | 
| 95 |  |  | : gzstreambase( name, open_mode), std::istream( &buf) {} | 
| 96 |  |  | gzstreambuf* rdbuf() { return gzstreambase::rdbuf(); } | 
| 97 |  |  | void open( const char* name, int open_mode = std::ios::in) { | 
| 98 |  |  | gzstreambase::open( name, open_mode); | 
| 99 |  |  | } | 
| 100 |  |  | }; | 
| 101 |  |  |  | 
| 102 |  |  | class ogzstream : public gzstreambase, public std::ostream { | 
| 103 |  |  | public: | 
| 104 |  |  | ogzstream() : std::ostream( &buf) {} | 
| 105 |  |  | ogzstream( const char* name, int mode = std::ios::out) | 
| 106 |  |  | : gzstreambase( name, mode), std::ostream( &buf) {} | 
| 107 |  |  | gzstreambuf* rdbuf() { return gzstreambase::rdbuf(); } | 
| 108 |  |  | void open( const char* name, int open_mode = std::ios::out) { | 
| 109 |  |  | gzstreambase::open( name, open_mode); | 
| 110 |  |  | } | 
| 111 |  |  | }; | 
| 112 |  |  |  | 
| 113 |  |  | } | 
| 114 |  |  | #endif | 
| 115 |  |  |  |