c/src/transport/axis/Channel.cpp

/* -*- C++ -*- */

/*
 * The Apache Software License, Version 1.1
 *
 *
 * Copyright (c) 2002 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. 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.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Axis" and "Apache Software Foundation" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache",
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 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
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 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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 * 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.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

/*
 *
 *
 * @author Lilantha Darshana (lilantha@virtusa.com)
 *
 */

#include <axis/client/transport/axis/Platform.hpp>
#include <axis/client/transport/axis/Channel.hpp>
#include <iostream>
#include <axis/client/transport/axis/Transport.hpp>

using namespace std;
/**
 * Create a Channel & initialize
 * 
 */

Channel::Channel() : m_Sock(INVALID_SOCKET)
{

}

Channel::~Channel()
{
	CloseChannel();
}


/**
 * This channel open INET channel for the time being using primitive sockets
 * Do we need any other type of channel; like shared memory, pipes etc. ????
 * 
 * @param	p_RemoteNode	End point address as hostname/IP
 * @param	p_RemoteEnd		Port #
 *
 * @return  true if successfuly open a soket to the endpoint. o/w exception is thrown
 */

bool Channel::Open(std::string& p_RemoteNode, unsigned short p_RemoteEnd) throw (ChannelException)
{
	m_RemoteNode = p_RemoteNode;
	m_RemoteEnd  = p_RemoteEnd;

	if(!Init())
		throw ChannelException("Cannot initialize a channel to the remote end");

	sockaddr_in clAddr, svAddr;			  

	if ((m_Sock = socket(PF_INET, SOCK_STREAM, 0)) != INVALID_SOCKET)
	{
		clAddr.sin_family = AF_INET;     // AF_INET (address family Internet).
		clAddr.sin_port   = 0; 			 // No Specify Port required
		clAddr.sin_addr.s_addr = INADDR_ANY;

		if (bind(m_Sock, (struct sockaddr*) &clAddr, sizeof(clAddr)) == SOCKET_ERROR)
		{
			Error("Error - Binding");
			CloseChannel();
			throw ChannelException("Cannot open a channel to the remote end, shutting down the channel");
		}

		// Although the above fragment makes use of the bind() API, it would be
		// just as effective to skip over this call as there are no specific
		// local port ID requirements for this client. The only advantage that
		// bind() offers is the accessibility of the port which the system chose
		// via the .sin_port member of the cli_addr structure which will be set
		// upon success of the bind() call.

		svAddr.sin_family = AF_INET;
		svAddr.sin_port   = htons(m_RemoteEnd);

		struct hostent*  pHostEntry = NULL;

		// probably this is the host-name of the server we are connecting to
		if((pHostEntry = gethostbyname(m_RemoteNode.c_str())))
		{
			svAddr.sin_addr.s_addr = ((struct in_addr *)pHostEntry->h_addr)->s_addr;
		}
		else
		{
			// no this is the IP address
			svAddr.sin_addr.s_addr = inet_addr(m_RemoteNode.c_str());	
		}

		// connect to the remote server.
		if (connect(m_Sock,(struct sockaddr*)&svAddr, sizeof(svAddr)) == SOCKET_ERROR)
		{
			Error("Sockets error Couldn't connect socket.");
			CloseChannel();
			throw ChannelException("Cannot open a channel to the remote end, shutting down the channel");
		}
	}
	else
	{
		Error("Sockets error Couldn't create socket.");
		CloseChannel();
		throw ChannelException("Cannot open a channel");
	}
	return true;
}

/**
 * OS specific initialization should do here
 *
 * @return  true if successfuly initilaize OS specific stuffs. false o/w
 */

bool Channel::Init()
{
#ifdef WIN32

	WSADATA wsaData;			// contains vendor-specific information, such as the
								// maximum number of sockets available and the maximum
								// datagram size.

	if(WSAStartup(WS_VERSION_REQD, &wsaData))  //Filled by Windows Sockets DLLs
	{
		m_LastErr = "WinSock DLL not responding.";
		Error((char *)m_LastErr.c_str());
		return false;
	}
	else
	{ 
		// Query to see whether the available version matches what we need
		if (( LOBYTE (wsaData.wVersion) < WS_VERSION_MAJOR()) ||
			 (LOBYTE (wsaData.wVersion) == WS_VERSION_MAJOR() &&
			  HIBYTE (wsaData.wVersion) < WS_VERSION_MINOR()))
		{
			char buf[100];
			sprintf(buf,"Windows Sockets version %d.%d not supported by winsock2.dll",
						LOBYTE (wsaData.wVersion), HIBYTE (wsaData.wVersion));
			Error(buf);
			CloseChannel();
			return false;
		}
	}
#else
    //cout << "no need for linux" << endl;
	// other OS specific Intitialization goes here
#endif
	return true;
}

/**
 * Write/send a message to the remote server; sending blocks the app.
 * we may need to do this asynchronizely; preferably either non-blocking
 * send or pthread.
 *
 * @param	Message to be written to the open channel
 */
const Channel& Channel::operator << (const char* msg)
{
	if(INVALID_SOCKET == m_Sock) 
	{
		Error("Writing cannot be done without having a open socket to remote end.");
		throw ChannelException("Output streaming error on undefined channel; please open the channel first");
	}

	int size = strlen(msg), nByteSent;
    
	if((nByteSent = send(m_Sock, msg, size, MSG_DONTROUTE )) == SOCKET_ERROR)
	{
		Error("Output streaming error while writing data.");
		CloseChannel();
		throw ChannelException("Output streaming error on Channel while writing data");
	}

	return *this;
}

/**
 * Read/receive a message from the remote server; reading may be done in chunks.
 *
 * @param	string to hold the read Message 
 */

const Channel& Channel::operator >> (std::string& msg)
{
	msg = "";
	if(INVALID_SOCKET == m_Sock) 
	{
		Error("Reading cannot be done without having a open socket.");
		throw ChannelException("Input streaming error on undefined channel; please open the channel first");
	}

	int nByteRecv = 0;
	const int BUF_SIZE = 4096;
	char buf[BUF_SIZE];
	
	do	// Manage multiple chuncks of the message
	{
		if ((nByteRecv = recv(m_Sock, (char *) &buf, BUF_SIZE - 1, 0)) == SOCKET_ERROR)
		{
			Error("Channel error while getting data.");
			CloseChannel();
			throw ChannelException("Input streaming error on Channel while getting data");
		}

		if(nByteRecv)
		{
			buf[nByteRecv + 1] = '\0';	// got a part of the message, so add it to form 
			msg += buf;					// the whole message

			//Validate according to the transport; check whether we are in a position to return.
			if (!m_pTransportHandler->GetStatus(msg)) 
				break;
		}
		else
			break; // we have the whole message or an error has occured
	 }
	 while (true);

	 return *this;
}

/**
 *	Close, and clean-up any OS specific stuff
 *
 */

void Channel::CloseChannel()
{
#ifdef WIN32
	if(INVALID_SOCKET != m_Sock)
		closesocket(m_Sock);
	
	// Check for any possible error conditions from WSACleanup() and report
	// them before exiting, as this information might indicate a network
	// layer problem in the system.

	WSACleanup();
#else
	if(INVALID_SOCKET != m_Sock)
		close(m_Sock);

#endif
}

/**
 * Log any errors that cause on channel usage/initilaization
 *
 */

void Channel::Error(const char * err)
{
#ifdef _DEBUG
	std::cerr << err << std::endl;
#endif
}