/*
** servereph.c
**	Written by Wei YIN, 20 August 2009.
**    before running change the parameter in gethostbyname() 
**
** 	Compile with "gcc -o servereph servereph.c"
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <ctype.h>
#include <netdb.h>
#include <sys/socket.h>

#define MAXSOCKADDR 128
void capitalise(char* str) {
    while(*str) {
	*str = (char)toupper((int)*str);
	str++;
    }
}

int main() {
    int fdServer;
    struct sockaddr_in serverAddr;

    struct sockaddr_in serverAddr2;
    
    socklen_t len = MAXSOCKADDR;//must be initialized
    
    struct hostent* hostp;
    struct in_addr* ipAddress;
    hostp = gethostbyname("moss");// use name of your host
    ipAddress = (struct in_addr*)hostp->h_addr_list[0];

    fdServer = socket(AF_INET, SOCK_STREAM, 0);


    serverAddr.sin_family = AF_INET;
    serverAddr.sin_port = htons(0); // system will allocate port number 
    serverAddr.sin_addr.s_addr = ipAddress->s_addr; //  IP address not htonl(INADDR_ANY)



    /* Bind socket to a given address */
    if(bind(fdServer, (struct sockaddr*)&serverAddr, sizeof(struct sockaddr_in))!=0){
	printf("bind error\n");
	return 1;
}

//get the ip addr and port number allocated by the system
    if(getsockname(fdServer,(struct sockaddr*)&serverAddr2,&len)== 0)
    {	
	printf("the port number is %d\n",htons(serverAddr2.sin_port));
	printf("ip address is %s\n",inet_ntoa(serverAddr2.sin_addr));
    }
else
	printf("getsocketname return error\n");
   
    /* Start listening on the socket */
    listen(fdServer, SOMAXCONN);	

    /* Accept connections, one after the other */
    while(1) {
	int fd;
	struct sockaddr_in fromAddr;
	int fromAddrSize;
	struct hostent* hp;
	FILE* connStreamIn;
	FILE* connStreamOut;
	char buffer[1024];


	fromAddrSize = sizeof(struct sockaddr_in);


	fd = accept(fdServer, (struct sockaddr*)&fromAddr, &fromAddrSize);


	
	/* Find out where the connection came from */
	hp=gethostbyaddr((char*)&fromAddr.sin_addr.s_addr,
		sizeof(fromAddr.sin_addr.s_addr), AF_INET);
	printf("Connection accepted from %s port %d\n",
		hp->h_name, ntohs(fromAddr.sin_port));

	connStreamIn = fdopen(fd, "r");
	connStreamOut = fdopen(fd, "w");


	while(fgets(buffer, 1024, connStreamIn)) {
	    if(strcmp(buffer,"Bye\n") == 0) {
		break;
	    }
	    capitalise(buffer);
	    fprintf(connStreamOut, "%s", buffer);
	    fflush(connStreamOut);
	}
	printf("Finishing up ...\n");
	fflush(stdout);
	fclose(connStreamIn);
	fclose(connStreamOut);
    }
}