/******************************************************************************
 * QUANTA - A toolkit for High Performance Data Sharing
 * Copyright (C) 2003 Electronic Visualization Laboratory,  
 * University of Illinois at Chicago
 *
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above
 *    copyright notice, this list of conditions and the following disclaimer
 *    in the documentation and/or other materials provided with the distribution.
 *  * Neither the name of the University of Illinois at Chicago nor
 *    the names of its contributors may be used to endorse or promote
 *    products derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Direct questions, comments etc about Quanta to cavern@evl.uic.edu
 *****************************************************************************/

/*
 * File name: QUANTAnet_iovec.hxx
 *
 * Description: This class is a container class for the iovec structure 
 *
 * Usasge: 1) readv(), writev() Methods in QUANTAnet_tcp_c class
 *         2) recvmsg(), sendmsg() Methods in QUANRTAnet_udp_c class
 *
 * Comments: QUANTAnet_iovec_c is a dynamic array of Iovec structures
 *			 Each Iovec strucure contains two values
 *           1) base pointer 2) its length
 *           You can add diffrenet type of objects to the QUANTAnet_iovec_c
 *  
 * How to use -> See: /QUANTA/demos/network/tcp/ioservertcp.cxx
 *											    ioclienttcp.cxx
 *
 * Change Log:
 */


#ifndef _QUANTANET_IOVEC
#define _QUANTANET_IOVEC

#ifndef __HAVE_STDIO_H
#include <stdio.h>
#define __HAVE_STDIO_H
#endif
#include <stdlib.h>


#include "QUANTAglobals.hxx"

#ifdef WIN32
#ifndef __HAVE_WINSOCK2_H
#include <winsock2.h>
#define __HAVE_WINSOCK2_H
#endif /* __HAVE_WINSOCK2_H */
#else
#include <sys/uio.h>
#endif

class QUANTAnet_iovec_c
{
	private:
		
		//keeps the number of elements in the iovec array
		int num_of_elements;

		//keeps the number of elements dynamically allocated
		int nalloc;
		
		//base pointer of the iovec dynamic array
#ifdef WIN32
		WSABUF* bufList;
#else
		struct iovec* bufList;
#endif
							
	public:		

		//constructor
		//By default bufList is allocated 512 entries because 
		//512*sizeof(iovec) = 4K(Page Size) to avoid page fault
		QUANTAnet_iovec_c(int size = 512);
		
		//destructor
		~QUANTAnet_iovec_c();
		
		/**
		@desc add the pointer and its length to the iovec array
		@param buff void*
    	@param length int
	    @return true or false
	    **/
		bool add(void* buff, int length);
			
		/**
		@desc remove the specific iovec entry			
    	@param index int
	    @return true or false
	    **/
		bool removeAt(int index);				
				
		/**
		@desc clear all entry in iovec array
	    @return void
	    **/
		void removeAll();
				
		/**
		@desc returns size of the iovec array    	
	    @return size int
	    **/
		int size();

		/**
		@desc used in readv(), writev() methods (internal use only)    	
	    @return base pointer of the dynamic array of iovec structures    			
	    **/
		
#ifdef WIN32
		WSABUF* getBuffer() {return bufList;}
#else
		const iovec* getBuffer() {return bufList;}
#endif

};

#endif