///////////////////////////////////////////////////////////////////////////////
//	File:		SocketComm.cpp
//	Version:	1.3
//
//	Author:		Ernest Laurentin
//	E-mail:		elaurentin@netzero.net
//
//	Implementation of the CSocketComm and associated classes.
//
//	This code may be used in compiled form in any way you desire. This
//	file may be redistributed unmodified by any means PROVIDING it is
//	not sold for profit without the authors written consent, and
//	providing that this notice and the authors name and all copyright
//	notices remains intact.
//
//	This file is provided "as is" with no expressed or implied warranty.
//	The author accepts no liability for any damage/loss of business that
//	this c++ class may cause.
//
//	Version history
//
//	1.0	- Initial release.
//	1.1 - Add support for Smart Addressing mode
//  1.2 - Fix various issues with address list (in UDP mode)
//  1.3 - Fix bug when sending message to broadcast address
///////////////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include <stdio.h>
#include <tchar.h>
#include <process.h>
#include <crtdbg.h>
#include "SocketComm.h"

const DWORD DEFAULT_TIMEOUT = 100L;
struct stMessageProxy
{
  SockAddrIn	address;
  BYTE			data[BUFFER_SIZE];
};

///////////////////////////////////////////////////////////////////////////////
// SockAddrIn Struct

///////////////////////////////////////////////////////////////////////////////
// Copy
SockAddrIn& SockAddrIn::Copy(const SockAddrIn& sin)
{
	memcpy(this, &sin, Size());
	return *this;
}

///////////////////////////////////////////////////////////////////////////////
// IsEqual
bool SockAddrIn::IsEqual(const SockAddrIn& sin)
{
	// Is it Equal? - ignore 'sin_zero'
	return (memcmp(this, &sin, Size()-sizeof(sin_zero)) == 0);
}

///////////////////////////////////////////////////////////////////////////////
// IsGreater
bool SockAddrIn::IsGreater(const SockAddrIn& sin)
{
	// Is it Greater? - ignore 'sin_zero'
	return (memcmp(this, &sin, Size()-sizeof(sin_zero)) > 0);
}

///////////////////////////////////////////////////////////////////////////////
// IsLower
bool SockAddrIn::IsLower(const SockAddrIn& sin)
{
	// Is it Lower? - ignore 'sin_zero'
	return (memcmp(this, &sin, Size()-sizeof(sin_zero)) < 0);
}

///////////////////////////////////////////////////////////////////////////////
// CreateFrom
bool SockAddrIn::CreateFrom(LPCTSTR sAddr, LPCTSTR sService, int nFamily /*=AF_INET*/)
{
	Clear();
	sin_addr.s_addr = htonl( CSocketComm::GetIPAddress(sAddr) );
	sin_port = htons( CSocketComm::GetPortNumber( sService ) );
	sin_family = nFamily;
	return !IsNull();
}


///////////////////////////////////////////////////////////////////////////////
// Construct & Destruct
CSocketComm::CSocketComm() :
	m_bServer(false), m_bSmartAddressing(false), m_bBroadcast(false),
	m_hComm(INVALID_HANDLE_VALUE), m_hThread(NULL), m_hMutex(NULL)
{

}

CSocketComm::~CSocketComm()
{
	StopComm();
}

///////////////////////////////////////////////////////////////////////////////
// Members
///////////////////////////////////////////////////////////////////////////////

///////////////////////////////////////////////////////////////////////////////
// IsOpen
bool CSocketComm::IsOpen() const
{
	return ( INVALID_HANDLE_VALUE != m_hComm );
}


///////////////////////////////////////////////////////////////////////////////
// IsStart
bool CSocketComm::IsStart() const
{
	return ( NULL != m_hThread );
}


///////////////////////////////////////////////////////////////////////////////
// IsServer
bool CSocketComm::IsServer() const
{
	return m_bServer;
}


///////////////////////////////////////////////////////////////////////////////
// IsBroadcast
bool CSocketComm::IsBroadcast() const
{
	return m_bBroadcast;
}


///////////////////////////////////////////////////////////////////////////////
// IsSmartAddressing
bool CSocketComm::IsSmartAddressing() const
{
	return m_bSmartAddressing;
}


///////////////////////////////////////////////////////////////////////////////
// GetSocket
SOCKET CSocketComm::GetSocket() const
{
	return (SOCKET) m_hComm;
}


///////////////////////////////////////////////////////////////////////////////
// LockList
void CSocketComm::LockList()
{
	if (NULL != m_hMutex)
		WaitForSingleObject(m_hMutex, INFINITE);
}


///////////////////////////////////////////////////////////////////////////////
// UnlockList
void CSocketComm::UnlockList()
{
	if (NULL != m_hMutex)
		ReleaseMutex(m_hMutex);
}


///////////////////////////////////////////////////////////////////////////////
// AddToList
void CSocketComm::AddToList(const SockAddrIn& saddr_in)
{
	LockList();
	m_AddrList.insert( m_AddrList.end(), saddr_in );
	UnlockList();
}

///////////////////////////////////////////////////////////////////////////////
// RemoveFromList
void CSocketComm::RemoveFromList(const SockAddrIn& saddr_in)
{
	LockList();
	m_AddrList.remove( saddr_in );
	UnlockList();
}

///////////////////////////////////////////////////////////////////////////////
// SetServerState
void CSocketComm::SetServerState(bool bServer)
{
	if (!IsStart())
		m_bServer = bServer;
}


///////////////////////////////////////////////////////////////////////////////
// SetSmartAddressing : Address is included with message
void CSocketComm::SetSmartAddressing(bool bSmartAddressing)
{
	if (!IsStart())
		m_bSmartAddressing = bSmartAddressing;
}

///////////////////////////////////////////////////////////////////////////////
// OnDataReceived
///////////////////////////////////////////////////////////////////////////////
// DESCRIPTION:
//				This function is PURE Virtual, you MUST overwrite it.  This is
//				called every time new data is available.
// PARAMETERS:
///////////////////////////////////////////////////////////////////////////////
void CSocketComm::OnDataReceived(const LPBYTE lpBuffer, DWORD dwCount)
{
}


///////////////////////////////////////////////////////////////////////////////
// OnEvent
///////////////////////////////////////////////////////////////////////////////
// DESCRIPTION:
//				This function reports events & errors
// PARAMETERS:
//		UINT uEvent: can be one of the event value EVT_(events)
///////////////////////////////////////////////////////////////////////////////
void CSocketComm::OnEvent(UINT uEvent)
{
}

///////////////////////////////////////////////////////////////////////////////
// GetPortNumber
///////////////////////////////////////////////////////////////////////////////
// DESCRIPTION:
//				Returns a port number based on service name or port number string
// PARAMETERS:
//	LPCTSTR strServiceName: Service name or port string
///////////////////////////////////////////////////////////////////////////////
USHORT CSocketComm::GetPortNumber( LPCTSTR strServiceName )
{
	LPSERVENT	lpservent;
	USHORT		nPortNumber = 0;

	if ( _istdigit( strServiceName[0] ) ) {
		nPortNumber = (USHORT) _ttoi( strServiceName );
	}
	else {
#ifdef _UNICODE
		char pstrService[HOSTNAME_SIZE];
		WideCharToMultiByte(CP_ACP, 0, pstrService, -1, strServiceName, sizeof(pstrService), NULL, NULL );
#else
		LPCTSTR pstrDevice = strServiceName;
#endif
		// Convert network byte order to host byte order
		if ( (lpservent = getservbyname( pstrDevice, NULL )) != NULL )
			nPortNumber = ntohs( lpservent->s_port );
	}

	return nPortNumber;
}


///////////////////////////////////////////////////////////////////////////////
// GetIPAddress
///////////////////////////////////////////////////////////////////////////////
// DESCRIPTION:
//		Returns an IP address.
//			- It tries to convert the string directly
//			- If that fails, it tries to resolve it as a hostname
// PARAMETERS:
//	LPCTSTR strHostName: host name to get IP address
///////////////////////////////////////////////////////////////////////////////
ULONG CSocketComm::GetIPAddress( LPCTSTR strHostName )
{
	LPHOSTENT	lphostent;
	ULONG		uAddr = INADDR_NONE;
	TCHAR       strLocal[HOSTNAME_SIZE] = { 0 };

	// if no name specified, get local
	if ( NULL == strHostName )
	{
		GetLocalName(strLocal, sizeof(strLocal));
		strHostName = strLocal;
	}

#ifdef _UNICODE
	char strHost[HOSTNAME_SIZE] = { 0 };
	WideCharToMultiByte(CP_ACP, 0, strHostName, -1, strHost, sizeof(strHost), NULL, NULL );
#else
	LPCTSTR strHost = strHostName;
#endif

	// Check for an Internet Protocol dotted address string
	uAddr = inet_addr( strHost );

	if ( (INADDR_NONE == uAddr) && (strcmp( strHost, "255.255.255.255" )) )
	{
		// It's not an address, then try to resolve it as a hostname
		if ( lphostent = gethostbyname( strHost ) )
			uAddr = *((ULONG *) lphostent->h_addr_list[0]);
	}
	
	return ntohl( uAddr );
}


///////////////////////////////////////////////////////////////////////////////
// GetLocalName
///////////////////////////////////////////////////////////////////////////////
// DESCRIPTION:
//				Get local computer name.  Something like: "mycomputer.myserver.net"
// PARAMETERS:
//	LPTSTR strName: name of the computer is returned here
//	UINT nSize: size max of buffer "strName"
///////////////////////////////////////////////////////////////////////////////
bool CSocketComm::GetLocalName(LPTSTR strName, UINT nSize)
{
	if (strName != NULL && nSize > 0)
	{
		char strHost[HOSTNAME_SIZE] = { 0 };

		// get host name, if fail, SetLastError is set
		if (SOCKET_ERROR != gethostname(strHost, sizeof(strHost)))
		{
			struct hostent* hp;
			hp = gethostbyname(strHost);
			if (hp != NULL)	{
				strcpy(strHost, hp->h_name);
			}

			// check if user provide enough buffer
			if (strlen(strHost) > nSize)
			{
				SetLastError(ERROR_INSUFFICIENT_BUFFER);
				return false;
			}

			// Unicode conversion
#ifdef _UNICODE
			return (0 != MultiByteToWideChar(CP_ACP, 0, strHost, -1, strName, nSize, NULL, NULL ));
#else
			_tcscpy(strName, strHost);
			return true;
#endif
		}
	}
	else
		SetLastError(ERROR_INVALID_PARAMETER);
	return false;
}


///////////////////////////////////////////////////////////////////////////////
// GetLocalAddress
///////////////////////////////////////////////////////////////////////////////
// DESCRIPTION:
//				Get TCP address of local computer in dot format ex: "127.0.0.0"
// PARAMETERS:
//	LPTSTR strAddress: pointer to hold address string, must be long enough
//	UINT nSize: maximum size of this buffer
///////////////////////////////////////////////////////////////////////////////
bool CSocketComm::GetLocalAddress(LPTSTR strAddress, UINT nSize)
{
	// Get computer local address
	if (strAddress != NULL && nSize > 0)
	{
		char strHost[HOSTNAME_SIZE] = { 0 };

		// get host name, if fail, SetLastError is called
		if (SOCKET_ERROR != gethostname(strHost, sizeof(strHost)))
		{
			struct hostent* hp;
			hp = gethostbyname(strHost);
			if (hp != NULL && hp->h_addr_list[0] != NULL)
			{
				// Address is four bytes (32-bit)
				if ( hp->h_length < 4)
					return false;

				// Convert address to . format
				strHost[0] = 0;

				// Create Address string
				sprintf(strHost, "%u.%u.%u.%u",
					(UINT)(((PBYTE) hp->h_addr_list[0])[0]),
					(UINT)(((PBYTE) hp->h_addr_list[0])[1]),
					(UINT)(((PBYTE) hp->h_addr_list[0])[2]),
					(UINT)(((PBYTE) hp->h_addr_list[0])[3]));

				// check if user provide enough buffer
				if (strlen(strHost) > nSize)
				{
					SetLastError(ERROR_INSUFFICIENT_BUFFER);
					return false;
				}

			// Unicode conversion
#ifdef _UNICODE
				return (0 != MultiByteToWideChar(CP_ACP, 0, strHost, -1, strAddress,
					nSize, NULL, NULL ));
#else
				_tcscpy(strAddress, strHost);
				return true;
#endif
			}
		}
	}
	else
		SetLastError(ERROR_INVALID_PARAMETER);
	return false;
}


///////////////////////////////////////////////////////////////////////////////
// WaitForConnection
///////////////////////////////////////////////////////////////////////////////
// DESCRIPTION:
//				Wait for a network connection.  Only for connection type of socket
//				This function may fail, in this case it returns "INVALID_SOCKET"
// PARAMETERS:
//	SOCKET sock: a socket capable of receiving new connection (TCP: SOCK_STREAM)
///////////////////////////////////////////////////////////////////////////////
SOCKET CSocketComm::WaitForConnection(SOCKET sock)
{
	// Accept an incoming connection - blocking
	// no information about remote address is returned
	return accept(sock, 0, 0);
}


///////////////////////////////////////////////////////////////////////////////
// ShutdownConnection
///////////////////////////////////////////////////////////////////////////////
// DESCRIPTION:
//				Shutdown a connection and close socket.  This will force all
//				transmission/reception to fail.
// PARAMETERS:
//	SOCKET sock: Socket to close
///////////////////////////////////////////////////////////////////////////////
bool CSocketComm::ShutdownConnection(SOCKET sock)
{
	shutdown(sock, SD_BOTH);
	return ( 0 == closesocket( sock ));
}


///////////////////////////////////////////////////////////////////////////////
// GetSockName
///////////////////////////////////////////////////////////////////////////////
// DESCRIPTION:
//				retrieves the local name for a socket
// PARAMETERS:
//	SockAddrIn& saddr_in: object to store address
///////////////////////////////////////////////////////////////////////////////
bool CSocketComm::GetSockName(SockAddrIn& saddr_in)
{
	if (IsOpen())
	{
		int namelen = saddr_in.Size();
		return (SOCKET_ERROR != getsockname(GetSocket(), (LPSOCKADDR)saddr_in, &namelen));
	}

	return false;
}


///////////////////////////////////////////////////////////////////////////////
// GetPeerName
///////////////////////////////////////////////////////////////////////////////
// DESCRIPTION:
//				retrieves the name of the peer to which a socket is connected
// PARAMETERS:
//	SockAddrIn& saddr_in: object to store address
///////////////////////////////////////////////////////////////////////////////
bool CSocketComm::GetPeerName(SockAddrIn& saddr_in)
{
	if (IsOpen())
	{
		int namelen = saddr_in.Size();
		return (SOCKET_ERROR != getpeername(GetSocket(), (LPSOCKADDR)saddr_in, &namelen));	
	}

	return false;
}


///////////////////////////////////////////////////////////////////////////////
// CreateSocket
///////////////////////////////////////////////////////////////////////////////
// DESCRIPTION:
//				This function creates a new socket for connection (SOCK_STREAM)
//				or an connectionless socket (SOCK_DGRAM).  A connectionless
//				socket should not call "accept()" since it cannot receive new
//				connection.  This is used as SERVER socket
// PARAMETERS:
//	LPCTSTR strServiceName: Service name or port number
//	int nFamily: address family to use (set to AF_INET)
//	int nType: type of socket to create (SOCK_STREAM, SOCK_DGRAM)
//	UINT uOptions: other options to use
///////////////////////////////////////////////////////////////////////////////
bool CSocketComm::CreateSocket(LPCTSTR strServiceName, int nFamily, int nType, UINT uOptions /* = 0 */)
{
	// Socket is already opened
	if ( IsOpen() )
		return false;

	// Create a Socket that is bound to a specific service provide
	// nFamily: (AF_INET)