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+// ============================================================================
+// gzstream, C++ iostream classes wrapping the zlib compression library.
+// Copyright (C) 2001 Deepak Bandyopadhyay, Lutz Kettner
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; either
+// version 2.1 of the License, or (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+// ============================================================================
+//
+// File : gzstream.h
+// Revision : $Revision: 1.5 $
+// Revision_date : $Date: 2002/04/26 23:30:15 $
+// Author(s) : Deepak Bandyopadhyay, Lutz Kettner
+//
+// Standard streambuf implementation following Nicolai Josuttis, "The
+// Standard C++ Library".
+// ============================================================================
+
+#ifndef GZSTREAM_H
+#define GZSTREAM_H 1
+
+// standard C++ with new header file names and std:: namespace
+#include <iostream>
+#include <fstream>
+#include <zlib.h>
+
+#ifdef GZSTREAM_NAMESPACE
+namespace GZSTREAM_NAMESPACE {
+#endif
+
+// ----------------------------------------------------------------------------
+// Internal classes to implement gzstream. See below for user classes.
+// ----------------------------------------------------------------------------
+
+class gzstreambuf : public std::streambuf {
+private:
+ static const int bufferSize = 47+(1024*256); // size of data buff
+ // totals 512 bytes under g++ for igzstream at the end.
+
+ gzFile file; // file handle for compressed file
+ char buffer[bufferSize]; // data buffer
+ char opened; // open/close state of stream
+ int mode; // I/O mode
+
+ int flush_buffer();
+ void handle_gzerror(); // throws exception
+public:
+#if defined(_WIN32) && !defined(CYGWIN) && !defined(EOF)
+ enum {
+ EOF = -1
+ };
+#endif
+ gzstreambuf() : opened(0) {
+ setp( buffer, buffer + (bufferSize-1));
+ setg( buffer + 4, // beginning of putback area
+ buffer + 4, // read position
+ buffer + 4); // end position
+ // ASSERT: both input & output capabilities will not be used together
+ }
+ int is_open() { return opened; }
+ gzstreambuf* open( const char* name, int open_mode);
+ gzstreambuf* close();
+ ~gzstreambuf() { close(); }
+
+ virtual int overflow( int c = EOF);
+ virtual int underflow();
+ virtual int sync();
+};
+
+class gzstreambase : virtual public std::ios {
+protected:
+ gzstreambuf buf;
+public:
+ gzstreambase() { init(&buf); }
+ gzstreambase( const char* name, int open_mode);
+ ~gzstreambase();
+ void open( const char* name, int open_mode);
+ void close();
+ gzstreambuf* rdbuf() { return &buf; }
+};
+
+// ----------------------------------------------------------------------------
+// User classes. Use igzstream and ogzstream analogously to ifstream and
+// ofstream respectively. They read and write files based on the gz*
+// function interface of the zlib. Files are compatible with gzip compression.
+// ----------------------------------------------------------------------------
+
+class igzstream : public gzstreambase, public std::istream {
+public:
+ igzstream() : std::istream( &buf) {}
+ igzstream( const char* name, int open_mode = std::ios::in)
+ : gzstreambase( name, std::ios::in | open_mode), std::istream( &buf) {}
+ gzstreambuf* rdbuf() { return gzstreambase::rdbuf(); }
+ void open( const char* name, int open_mode = std::ios::in) {
+ gzstreambase::open( name, open_mode);
+ }
+};
+
+class ogzstream : public gzstreambase, public std::ostream {
+public:
+ ogzstream() : std::ostream( &buf) {}
+ ogzstream( const char* name, int mode = std::ios::out)
+ : gzstreambase( name, mode), std::ostream( &buf) {}
+ gzstreambuf* rdbuf() { return gzstreambase::rdbuf(); }
+ void open( const char* name, int open_mode = std::ios::out) {
+ gzstreambase::open( name, open_mode);
+ }
+};
+
+#ifdef GZSTREAM_NAMESPACE
+} // namespace GZSTREAM_NAMESPACE
+#endif
+
+#endif // GZSTREAM_H
+// ============================================================================
+// EOF //
+