| 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.C | 
| 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 |  |  | #include <iostream> | 
| 30 |  |  | #include <string.h>  // for memcpy | 
| 31 |  |  | #include "io/gzstream.hpp" | 
| 32 |  |  |  | 
| 33 |  |  | namespace oopse { | 
| 34 |  |  |  | 
| 35 |  |  | // ---------------------------------------------------------------------------- | 
| 36 |  |  | // Internal classes to implement gzstream. See header file for user classes. | 
| 37 |  |  | // ---------------------------------------------------------------------------- | 
| 38 |  |  |  | 
| 39 |  |  | // -------------------------------------- | 
| 40 |  |  | // class gzstreambuf: | 
| 41 |  |  | // -------------------------------------- | 
| 42 |  |  |  | 
| 43 |  |  | gzstreambuf* gzstreambuf::open( const char* name, int open_mode) { | 
| 44 |  |  | if ( is_open()) | 
| 45 |  |  | return (gzstreambuf*)0; | 
| 46 |  |  | mode = open_mode; | 
| 47 |  |  | // no append nor read/write mode | 
| 48 |  |  | if ((mode & std::ios::ate) || (mode & std::ios::app) | 
| 49 |  |  | || ((mode & std::ios::in) && (mode & std::ios::out))) | 
| 50 |  |  | return (gzstreambuf*)0; | 
| 51 |  |  | char  fmode[10]; | 
| 52 |  |  | char* fmodeptr = fmode; | 
| 53 |  |  | if ( mode & std::ios::in) | 
| 54 |  |  | *fmodeptr++ = 'r'; | 
| 55 |  |  | else if ( mode & std::ios::out) | 
| 56 |  |  | *fmodeptr++ = 'w'; | 
| 57 |  |  | *fmodeptr++ = 'b'; | 
| 58 |  |  | *fmodeptr = '\0'; | 
| 59 |  |  | file = gzopen( name, fmode); | 
| 60 |  |  | if (file == 0) | 
| 61 |  |  | return (gzstreambuf*)0; | 
| 62 |  |  | opened = 1; | 
| 63 |  |  | return this; | 
| 64 |  |  | } | 
| 65 |  |  |  | 
| 66 |  |  | gzstreambuf * gzstreambuf::close() { | 
| 67 |  |  | if ( is_open()) { | 
| 68 |  |  | sync(); | 
| 69 |  |  | opened = 0; | 
| 70 |  |  | if ( gzclose( file) == Z_OK) | 
| 71 |  |  | return this; | 
| 72 |  |  | } | 
| 73 |  |  | return (gzstreambuf*)0; | 
| 74 |  |  | } | 
| 75 |  |  |  | 
| 76 |  |  | int gzstreambuf::underflow() { // used for input buffer only | 
| 77 |  |  | if ( gptr() && ( gptr() < egptr())) | 
| 78 |  |  | return * reinterpret_cast<unsigned char *>( gptr()); | 
| 79 |  |  |  | 
| 80 |  |  | if ( ! (mode & std::ios::in) || ! opened) | 
| 81 |  |  | return EOF; | 
| 82 |  |  | // Josuttis' implementation of inbuf | 
| 83 |  |  | int n_putback = gptr() - eback(); | 
| 84 |  |  | if ( n_putback > 4) | 
| 85 |  |  | n_putback = 4; | 
| 86 |  |  | memcpy( buffer + (4 - n_putback), gptr() - n_putback, n_putback); | 
| 87 |  |  |  | 
| 88 |  |  | int num = gzread( file, buffer+4, bufferSize-4); | 
| 89 |  |  | if (num <= 0) // ERROR or EOF | 
| 90 |  |  | return EOF; | 
| 91 |  |  |  | 
| 92 |  |  | // reset buffer pointers | 
| 93 |  |  | setg( buffer + (4 - n_putback),   // beginning of putback area | 
| 94 |  |  | buffer + 4,                 // read position | 
| 95 |  |  | buffer + 4 + num);          // end of buffer | 
| 96 |  |  |  | 
| 97 |  |  | // return next character | 
| 98 |  |  | return * reinterpret_cast<unsigned char *>( gptr()); | 
| 99 |  |  | } | 
| 100 |  |  |  | 
| 101 |  |  | int gzstreambuf::flush_buffer() { | 
| 102 |  |  | // Separate the writing of the buffer from overflow() and | 
| 103 |  |  | // sync() operation. | 
| 104 |  |  | int w = pptr() - pbase(); | 
| 105 |  |  | if ( gzwrite( file, pbase(), w) != w) | 
| 106 |  |  | return EOF; | 
| 107 |  |  | pbump( -w); | 
| 108 |  |  | return w; | 
| 109 |  |  | } | 
| 110 |  |  |  | 
| 111 |  |  | int gzstreambuf::overflow( int c) { // used for output buffer only | 
| 112 |  |  | if ( ! ( mode & std::ios::out) || ! opened) | 
| 113 |  |  | return EOF; | 
| 114 |  |  | if (c != EOF) { | 
| 115 |  |  | *pptr() = c; | 
| 116 |  |  | pbump(1); | 
| 117 |  |  | } | 
| 118 |  |  | if ( flush_buffer() == EOF) | 
| 119 |  |  | return EOF; | 
| 120 |  |  | return c; | 
| 121 |  |  | } | 
| 122 |  |  |  | 
| 123 |  |  | int gzstreambuf::sync() { | 
| 124 |  |  | // Changed to use flush_buffer() instead of overflow( EOF) | 
| 125 |  |  | // which caused improper behavior with std::endl and flush(), | 
| 126 |  |  | // bug reported by Vincent Ricard. | 
| 127 |  |  | if ( pptr() && pptr() > pbase()) { | 
| 128 |  |  | if ( flush_buffer() == EOF) | 
| 129 |  |  | return -1; | 
| 130 |  |  | } | 
| 131 |  |  | return 0; | 
| 132 |  |  | } | 
| 133 |  |  |  | 
| 134 |  |  | // -------------------------------------- | 
| 135 |  |  | // class gzstreambase: | 
| 136 |  |  | // -------------------------------------- | 
| 137 |  |  |  | 
| 138 |  |  | gzstreambase::gzstreambase( const char* name, int mode) { | 
| 139 |  |  | init( &buf); | 
| 140 |  |  | open( name, mode); | 
| 141 |  |  | } | 
| 142 |  |  |  | 
| 143 |  |  | gzstreambase::~gzstreambase() { | 
| 144 |  |  | buf.close(); | 
| 145 |  |  | } | 
| 146 |  |  |  | 
| 147 |  |  | void gzstreambase::open( const char* name, int open_mode) { | 
| 148 |  |  | if ( ! buf.open( name, open_mode)) | 
| 149 |  |  | clear( rdstate() | std::ios::badbit); | 
| 150 |  |  | } | 
| 151 |  |  |  | 
| 152 |  |  | void gzstreambase::close() { | 
| 153 |  |  | if ( buf.is_open()) | 
| 154 |  |  | if ( ! buf.close()) | 
| 155 |  |  | clear( rdstate() | std::ios::badbit); | 
| 156 |  |  | } | 
| 157 |  |  |  | 
| 158 |  |  |  | 
| 159 |  |  | } // namespace GZSTREAM_NAMESPACE | 
| 160 |  |  |  |