zstream.cpp

贡献一份commoncpp2,有兴趣的可以研究一下

// Copyright (C) 1999-2005 Open Source Telecom Corporation.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
// 
// This program 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software 
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
// 
// As a special exception, you may use this file as part of a free software
// library without restriction.  Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License.  This exception does not however    
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.    
//
// This exception applies only to the code released under the name GNU
// Common C++.  If you copy code from other releases into a copy of GNU
// Common C++, as the General Public License permits, the exception does
// not apply to the code that you add in this way.  To avoid misleading
// anyone as to the status of such modified files, you must delete
// this exception notice from them.
//
// If you write modifications of your own for GNU Common C++, it is your choice
// whether to permit this exception to apply to your modifications.
// If you do not wish that, delete this exception notice.
//

#ifdef	HAVE_ZLIB_H

#include <cc++/config.h>
#ifdef	CCXX_WITHOUT_EXTRAS
#include <cc++/export.h>
#endif
#include <cc++/thread.h>
#include <cc++/exception.h>
#ifndef	CCXX_WITHOUT_EXTRAS
#include <cc++/export.h>
#endif
#include <cc++/zstream.h>
#include <cerrno>
#include <cstdlib>
#include <cstdarg>
#include <cstdio>

#ifdef	WIN32
#include <io.h>
#endif

#ifdef	CCXX_NAMESPACES
namespace ost {
using namespace std;
#endif

IZStream::IZStream(const char *name, size_t size, bool tf) :
streambuf(),
#ifdef	HAVE_OLD_IOSTREAM
	istream(),
#else
	istream((streambuf *)this),
#endif
	bufsize(0),gbuf(NULL),fp(0)
{
#ifdef	HAVE_OLD_IOSTREAM
	init((streambuf *)this);
#endif

	throwflag = tf;
	fp = ::gzopen(name, "rb");
	if(!fp)
	{
#ifdef	COMMON_STD_EXCEPTION
		if(Thread::getException() == Thread::throwException && throwflag)
			throw IOZException(String(::gzerror(fp, NULL)));
#endif
		clear(ios::failbit | rdstate());
		return;
	}

	allocate(size);
}

IZStream::IZStream(bool tf) :
streambuf(),
#ifdef  HAVE_OLD_IOSTREAM
        istream(),
#else
        istream((streambuf *)this),
#endif
        bufsize(0),gbuf(NULL),fp(0)
{
#ifdef	HAVE_OLD_IOSTREAM
	init((streambuf *)this);
#endif
	throwflag = tf;
}

IZStream::~IZStream()
{
	close();
}

void IZStream::open(const char *name, size_t size)
{
	if(fp)
		close();

	fp = ::gzopen(name, "rb");
	if(!fp)
	{
#ifdef	COMMON_STD_EXCEPTION
		if(Thread::getException() == Thread::throwException && throwflag)
			throw IOZException(String(::gzerror(fp, NULL)));
#endif
		clear(ios::failbit | rdstate());
		return;
	}
	allocate(size);
}

void IZStream::close(void)
{
	if(gbuf)
		delete[] gbuf;
	
	::gzclose(fp);
	fp = 0;

	gbuf = NULL;
	bufsize = 0;
	clear();
}

void IZStream::allocate(size_t size)
{
	if(size < 2)
	{
		bufsize = 1;
		gbuf = 0;
		return;
	}

	gbuf = new char[size];
	if(!gbuf)
		return;
	bufsize = size;
	clear();

#if (defined(__GNUC__) && (__GNUC__ < 3)) && !defined(WIN32) && !defined(STLPORT)
	setb(gbuf, gbuf + size, 0);
#endif
	setg(gbuf, gbuf + size, gbuf + size);
}

int IZStream::doallocate()
{
	if(bufsize)
		return 0;

	allocate(1);
	return 1;
}

bool IZStream::isOpen(void)
{
	if(fp)
		return true;

	return false;
}

int IZStream::uflow()
{
	int ret = underflow();

	if (ret == EOF)
		return EOF; 

	if (bufsize != 1)
		gbump(1); 

	return ret; 
}

int IZStream::underflow()
{
	ssize_t rlen = 1;
	unsigned char ch;

	if(bufsize == 1)
	{
		rlen = ::gzread(fp, &ch, 1);
		if(rlen < 1)
		{
			if(rlen < 0)
				clear(ios::failbit | rdstate());
			return EOF;
		}
		return ch;
	}

	if(!gptr())
		return EOF;

	if(gptr() < egptr())
		return (unsigned char)*gptr();

	rlen = (ssize_t)((gbuf + bufsize) - eback());
	rlen = ::gzread(fp, eback(), rlen);
	if(rlen < 1)
	{
		clear(ios::failbit | rdstate());
		return EOF;
	}

	setg(eback(), eback(), eback() + rlen);
	return (unsigned char) *gptr();
}



OZStream::OZStream(const char *name, int level, size_t size, bool tf) :
streambuf(),
#ifdef	HAVE_OLD_IOSTREAM
	ostream(),
#else
	ostream((streambuf *)this),
#endif
	bufsize(0),pbuf(NULL),fp(0)
{
	char mode[4];

#ifdef	HAVE_OLD_IOSTREAM
	init((streambuf *)this);
#endif
	
	strcpy(mode, "wb\0");
	if(level != Z_DEFAULT_COMPRESSION)
		mode[2] = '0' + level;
		
	throwflag = tf;
	fp = ::gzopen(name, mode);
	if(!fp)
	{
#ifdef	COMMON_STD_EXCEPTION
		if(Thread::getException() == Thread::throwException && throwflag)
			throw IOZException(String(::gzerror(fp, NULL)));
#endif
		clear(ios::failbit | rdstate());
		return;
	}

	allocate(size);
}

OZStream::OZStream(bool tf) :
streambuf(),
#ifdef  HAVE_OLD_IOSTREAM
        ostream(),
#else
        ostream((streambuf *)this),
#endif
        bufsize(0),pbuf(NULL),fp(0)
{
#ifdef	HAVE_OLD_IOSTREAM
	init((streambuf *)this);
#endif
	throwflag = tf;
}

OZStream::~OZStream()
{
	close();
}

void OZStream::open(const char *name, int level, size_t size)
{
	char mode[4];
	
	if(fp)
		close();
		
	strcpy(mode, "wb\0");
	if(level != Z_DEFAULT_COMPRESSION)
		mode[2] = '0' + level;

	fp = ::gzopen(name, mode);
	if(!fp)
	{
#ifdef	COMMON_STD_EXCEPTION
		if(Thread::getException() == Thread::throwException && throwflag)
			throw IOZException(String(::gzerror(fp, NULL)));
#endif
		clear(ios::failbit | rdstate());
		return;
	}
	allocate(size);
}

void OZStream::close(void)
{
	if(pbuf)
		delete[] pbuf;
	
	::gzclose(fp);
	fp = 0;

	pbuf = NULL;
	bufsize = 0;
	clear();
}

void OZStream::allocate(size_t size)
{
	if(size < 2)
	{
		bufsize = 1;
		pbuf = 0;
		return;
	}

	pbuf = new char[size];
	if(!pbuf)
		return;
	bufsize = size;
	clear();

	setp(pbuf, pbuf + size);
}

int OZStream::doallocate()
{
	if(bufsize)
		return 0;

	allocate(1);
	return 1;
}

bool OZStream::isOpen(void)
{
	if(fp)
		return true;

	return false;
}

int OZStream::overflow(int c)
{
	unsigned char ch;
	ssize_t rlen, req;

	if(bufsize == 1)
	{
		if(c == EOF)
			return 0;

		ch = (unsigned char)(c);
		rlen = ::gzwrite(fp, &ch, 1);
		if(rlen < 1)
		{
			if(rlen < 0)
				clear(ios::failbit | rdstate());
			return EOF;
		}
		else
			return c;
	}

	if(!pbase())
		return EOF;

	req = (ssize_t)(pptr() - pbase());
	if(req)
	{
		rlen = ::gzwrite(fp, pbase(), req);
		if(rlen < 1)
		{
			if(rlen < 0)
				clear(ios::failbit | rdstate());
			return EOF;
		}
		req -= rlen;
	}

	// if write "partial", rebuffer remainder

	if(req)
		memmove(pbuf, pbuf + rlen, req);
	setp(pbuf, pbuf + bufsize);
	pbump(req);

	if(c != EOF)
	{
		*pptr() = (unsigned char)c;
		pbump(1);
	}
	return c;
}


#ifdef  CCXX_NAMESPACES
}
#endif

#endif