Networking Code for Linux

//
// com_object.h
//
#ifndef _COM_OBJECT_H_
#define _COM_OBJECT_H_

#include 

// that is one big message
#define	MESSAGE_SIZE		4096	

#define	RECV_MSG_TYPE		1
#define SEND_MSG_TYPE		2

class Com_Object {

public:
	Com_Object();
	~Com_Object();

	void Load_Address(const char *ip, const int port);

	void Init(void);

	void Connect(void);
	void Disconnect(void);
	void SendMsg(const char *msg); 
	void RecvMsg(void);
	void Recv(void);	// recv character at a time
	void GetMsg(char *res_msg)
	{ strcpy(res_msg, m_aMsg); }

private:

	char ComGetChar(void);	// get chars one at a time
	
	char	m_aHostName[256];
	bool	m_bConnectFlag;
	int	m_iPortNo;
	int	m_iSocketDesc;		// socket descriptor
	char 	m_aMsg[MESSAGE_SIZE];	// send and receive messages

	int	m_iMsgType;	// last message type recv/send
	int	m_iMsgSize;
};



#endif

//
// com_object.cpp
//
#include 

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 

#include "com_object.h"

#include "game.h"

//
// Com
//
Com_Object::Com_Object()
{
	Init();
} // end of the function 

Com_Object::~Com_Object()
{
} // end of teh functino 

//
// Init
// 
void Com_Object::Init(void)
{
	m_bConnectFlag = false;

	m_iPortNo	= -1;
	
} // end of the functio 

//
// Load IP
//
void Com_Object::Load_Address(const char *ip, const int port)
{

	strcpy(m_aHostName, ip);

	m_iPortNo = port;

} // end of the function 

//
// Disconnect
// - this can be tricky, but I think the 
// best time to call this function would be
// before you delete the object
// 
void Com_Object::Disconnect(void)
{
	close(m_iSocketDesc);

	m_bConnectFlag = false;
} // end of the function 

//
// Send Msg
//
void Com_Object::SendMsg(const char *msg)
{
	strcpy(m_aMsg, msg);

	m_iMsgType = SEND_MSG_TYPE;

	m_iMsgSize = strlen(m_aMsg);

	if (send(m_iSocketDesc, m_aMsg, strlen(m_aMsg) + 1, 0) < 0)
	{
		Game_Error("send() failed:\n");
	} // end of the if 

} // end of the function 

//
// RcvMsg
//
void Com_Object::RecvMsg(void)
{
	recv(m_iSocketDesc, m_aMsg, sizeof(m_aMsg), 0);

	// get the string length
	m_iMsgSize = strlen(m_aMsg);

} // end of the function 

//
// ComGetChar
//  - wait for new line
char Com_Object::ComGetChar(void)
{
	char tiny[10];
	recv(m_iSocketDesc, tiny, 1, 0);
	tiny[1] = '\0';

	return tiny[0];
} // end of tehfunction 

//
// Recv only a char at a time
//
void Com_Object::Recv(void)
{
	char c;
	int index= 0;

	while(1)
	{
		c = ComGetChar();
		m_aMsg[index] = c;

		if (index >= MESSAGE_SIZE)
		{
			m_aMsg[MESSAGE_SIZE-1] = '\0';
			break;
		} // end of the if 

		// break on a new line, we may get a carriage
		// return though
		if (c == '\n')
		{
			m_aMsg[index] = c;
			index++;	// for null terminator
			m_aMsg[index] = '\0';
			break;
		} // end of the if 

		index++;

	} // end of the while 

	m_iMsgSize = index;	// I hope this close
	
	m_iMsgType = RECV_MSG_TYPE;

	// Note: newline should be included


} // end of the function 

//
// Connect
//
void Com_Object::Connect(void)
{

	struct sockaddr_in	serv_addr;
	struct hostent		*hp;


	if (m_bConnectFlag)
		return;		// already connected
	
	if ((hp = gethostbyname(m_aHostName)) == NULL)
	{
		Game_Error("gethostbyname() failed:\n");
	} // end of the if 
	
	m_iSocketDesc = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);

	if (m_iSocketDesc < 0)
		Game_Error("socket() failed: exiting\n");

	// load the server address structure
	memset(&serv_addr, 0, sizeof(serv_addr));

	memcpy(&serv_addr.sin_addr, hp->h_addr, hp->h_length);
	serv_addr.sin_family	= hp->h_addrtype;	// IP family
	serv_addr.sin_port		= htons(m_iPortNo);

	// get connection
	if (connect(m_iSocketDesc, (struct sockaddr *)&serv_addr, 
			sizeof(serv_addr)) < 0)
	{
		Game_Error("connect():\n");
	} // end of if 
	
	
} // end of the function