1 // ============================================================================
2 // gzstream, C++ iostream classes wrapping the zlib compression library.
3 // Copyright (C) 2001 Deepak Bandyopadhyay, Lutz Kettner
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.
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.
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 // ============================================================================
21 // Revision : $Revision: 1.4 $
22 // Revision_date : $Date: 2005/04/26 10:30:24 $
23 // Author(s) : Deepak Bandyopadhyay, Lutz Kettner
25 // Standard streambuf implementation following Nicolai Josuttis, "The
26 // Standard C++ Library".
27 // ============================================================================
34 # include <string.h> // for memcpy
37 #ifdef GZSTREAM_NAMESPACE
38 namespace GZSTREAM_NAMESPACE {
41 // ----------------------------------------------------------------------------
42 // Internal classes to implement gzstream. See header file for user classes.
43 // ----------------------------------------------------------------------------
45 // --------------------------------------
47 // --------------------------------------
49 gzstreambuf* gzstreambuf::open( const char* name, int open_mode) {
51 return (gzstreambuf*)0;
53 // no append nor read/write mode
54 if ((mode & std::ios::ate) || (mode & std::ios::app)
55 || ((mode & std::ios::in) && (mode & std::ios::out)))
56 return (gzstreambuf*)0;
58 char* fmodeptr = fmode;
59 if ( mode & std::ios::in)
61 else if ( mode & std::ios::out)
65 file = gzopen( name, fmode);
67 return (gzstreambuf*)0;
72 gzstreambuf * gzstreambuf::close() {
76 if ( gzclose( file) == Z_OK)
79 return (gzstreambuf*)0;
82 int gzstreambuf::underflow() { // used for input buffer only
83 if ( gptr() && ( gptr() < egptr()))
84 return * reinterpret_cast<unsigned char *>( gptr());
86 if ( ! (mode & std::ios::in) || ! opened)
88 // Josuttis' implementation of inbuf
89 int n_putback = gptr() - eback();
92 memcpy( buffer + (4 - n_putback), gptr() - n_putback, n_putback);
94 int num = gzread( file, buffer+4, bufferSize-4);
95 if (num <= 0) // ERROR or EOF
98 // reset buffer pointers
99 setg( buffer + (4 - n_putback), // beginning of putback area
100 buffer + 4, // read position
101 buffer + 4 + num); // end of buffer
103 // return next character
104 return * reinterpret_cast<unsigned char *>( gptr());
107 int gzstreambuf::flush_buffer() {
108 // Separate the writing of the buffer from overflow() and
110 int w = pptr() - pbase();
111 if ( gzwrite( file, pbase(), w) != w)
117 int gzstreambuf::overflow( int c) { // used for output buffer only
118 if ( ! ( mode & std::ios::out) || ! opened)
124 if ( flush_buffer() == EOF)
129 int gzstreambuf::sync() {
130 // Changed to use flush_buffer() instead of overflow( EOF)
131 // which caused improper behavior with std::endl and flush(),
132 // bug reported by Vincent Ricard.
133 if ( pptr() && pptr() > pbase()) {
134 if ( flush_buffer() == EOF)
140 // --------------------------------------
141 // class gzstreambase:
142 // --------------------------------------
144 gzstreambase::gzstreambase( const char* name, int mode) {
149 gzstreambase::~gzstreambase() {
153 void gzstreambase::open( const char* name, int open_mode) {
154 if ( ! buf.open( name, open_mode))
155 clear( rdstate() | std::ios::badbit);
158 void gzstreambase::close() {
161 clear( rdstate() | std::ios::badbit);
164 #ifdef GZSTREAM_NAMESPACE
165 } // namespace GZSTREAM_NAMESPACE
168 // ============================================================================