server.cpp

#define  _CRT_SECURE_NO_WARNINGS
#include <winsock.h>
#include <iostream>
#include <windows.h>
#include <time.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <stdio.h>
#include <process.h>
#include "Thread.h"
#include "server.h"
#include <string>
#include <ctime> 
#include <chrono>
TcpServer::TcpServer()
{
	WSADATA wsadata;
	if (WSAStartup(0x0202, &wsadata) != 0)
	{
		
		TcpThread::err_sys("Starting WSAStartup() error\n");
	}
	//Display name of local host
	if (gethostname(servername, HOSTNAME_LENGTH) != 0) //get the hostname
		TcpThread::err_sys("Get the host name error,exit");

	printf("Server: %s waiting to be contacted for time/size request...\n", servername);


	//Create the server socket
	if ((serverSock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0)
		TcpThread::err_sys("Create socket error,exit");

	//Fill-in Server Port and Address info.
	ServerPort = REQUEST_PORT;
	memset(&ServerAddr, 0, sizeof(ServerAddr));      /* Zero out structure */
	ServerAddr.sin_family = AF_INET;                 /* Internet address family */
	ServerAddr.sin_addr.s_addr = htonl(INADDR_ANY);  /* Any incoming interface */
	ServerAddr.sin_port = htons(ServerPort);         /* Local port */

	//Bind the server socket
	if (bind(serverSock, (struct sockaddr *) &ServerAddr, sizeof(ServerAddr)) < 0)
		TcpThread::err_sys("Bind socket error,exit");

	//Successfull bind, now listen for Server requests.
	if (listen(serverSock, MAXPENDING) < 0)
		TcpThread::err_sys("Listen socket error,exit");
}

TcpServer::~TcpServer()
{
	WSACleanup();
}


void TcpServer::start()
{
	for (;;) /* Run forever */
	{
		/* Set the size of the result-value parameter */
		clientLen = sizeof(ClientAddr);

		/* Wait for a Server to connect */
		if ((clientSock = accept(serverSock, (struct sockaddr *) &ClientAddr,
			&clientLen)) < 0)
			TcpThread::err_sys("Accept Failed ,exit");

		/* Create a Thread for this new connection and run*/
		TcpThread * pt = new TcpThread(clientSock);
		pt->start();
	}
}

//////////////////////////////TcpThread Class //////////////////////////////////////////
void TcpThread::err_sys(const char * fmt, ...)
{
	perror(NULL);
	va_list args;
	va_start(args, fmt);
	fprintf(stderr, "error: ");
	vfprintf(stderr, fmt, args);
	fprintf(stderr, "\n");
	va_end(args);
	exit(1);
}
unsigned long TcpThread::ResolveName(char name[])
{
	struct hostent *host;            /* Structure containing host information */

	if ((host = gethostbyname(name)) == NULL)
		err_sys("gethostbyname() failed");

	/* Return the binary, network byte ordered address */
	return *((unsigned long *)host->h_addr_list[0]);
}

/*
msg_recv returns the length of bytes in the msg_ptr->buffer,which have been recevied successfully.
*/
int TcpThread::msg_recv(int sock, Msg * msg_ptr)
{
	int rbytes, n;

	for (rbytes = 0;rbytes < MSGHDRSIZE;rbytes += n)
		if ((n = recv(sock, (char *)msg_ptr + rbytes, MSGHDRSIZE - rbytes, 0)) <= 0)
			err_sys("Recv MSGHDR Error");

	for (rbytes = 0;rbytes < msg_ptr->length;rbytes += n)
		if ((n = recv(sock, (char *)msg_ptr->buffer + rbytes, msg_ptr->length - rbytes, 0)) <= 0)
			err_sys("Recevier Buffer Error");

	return msg_ptr->length;
}

/* msg_send returns the length of bytes in msg_ptr->buffer,which have been sent out successfully
*/
int TcpThread::msg_send(int sock, Msg * msg_ptr)
{
	int n;
	if ((n = send(sock, (char *)msg_ptr, MSGHDRSIZE + msg_ptr->length, 0)) != (MSGHDRSIZE + msg_ptr->length))
		err_sys("Send MSGHDRSIZE+length Error");
	return (n - MSGHDRSIZE);

}

void TcpThread::run() //cs: Server socket
{
	Resp * respp;//a pointer to response
	Req * reqp; //a pointer to the Request Packet
	Msg smsg, rmsg; //send_message receive_message
	struct _stat stat_buf;
	int result;

	if (msg_recv(cs, &rmsg) != rmsg.length)
		err_sys("Receive Req error,exit");

	//cast it to the request packet structure		
	reqp = (Req *)rmsg.buffer;
	printf("Receive a request from client:%s\n", reqp->hostname);
	printf("HTTP version: HTTP/%f\n", reqp->http_version);
	printf("Method: %s\n", reqp->http_method == 1 ? "GET" : "POST");
	printf("Webpage name: %s\n", reqp->webPageName);
	printf("Timestamp: %s\n", reqp->timeStamp);

	//construct the response and send it out
	smsg.type = RESP;
	smsg.length = sizeof(Resp);

	respp = (Resp *)smsg.buffer;
	if ((result = _stat(reqp->webPageName, &stat_buf)) != 0) {
		// set response status number
		respp->status_code = 501;
		//  save time stamp
		memset(respp->timeStamp, 0, sizeof(respp->timeStamp));
		auto end = std::chrono::system_clock::now();
		std::time_t end_time = std::chrono::system_clock::to_time_t(end);
		sprintf(respp->timeStamp, "%s", std::ctime(&end_time));

	}
	else {
		// set response status number
		respp->status_code = 200;
		//  save time stamp
		memset(respp->timeStamp, 0, sizeof(respp->timeStamp));
		auto end = std::chrono::system_clock::now();
		std::time_t end_time = std::chrono::system_clock::to_time_t(end);
		sprintf(respp->timeStamp, "%s", std::ctime(&end_time));
	}
		
	

	if (msg_send(cs, &smsg) != smsg.length)
		err_sys("send Respose failed,exit");
	printf("Response for %s has been sent out \n\n\n", reqp->hostname);

	closesocket(cs);
	puts(" You will have to enter control-C to kill the program.");
}



////////////////////////////////////////////////////////////////////////////////////////

int main(void)
{

	TcpServer ts;
	ts.start();

	return 0;
}