/* Socket Client: Compilation: gcc client.c -o client
                   to run: client [local_port] [remote_host] [remote_port]

**** PS: The clients must be running before executing the server *****

*/

#include <arpa/inet.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <netdb.h>

#define SIZE 1000 // vector size

//############################################################################################

int main(int argc, char* argv[])
{
    int
         S0, S1,
         loc_port,  // local port
         rem_port, // remote port
         *vector,
         dsr; // descriptor of remote socket

    char    *host;

    struct sockaddr_in              loc_addr; // internet address
    struct sockaddr_in              rem_addr; // internet address
    struct hostent                 *phost; // pointer to host entry structure


	if(argc < 3){
	  printf("Erro uso correto:\n");
	  printf("     %s <localport_number> <hostname> <port_number>\n\n", argv[0]);
	  exit(1);
	}



    //clean structure
    memset((char *)&rem_addr,0,sizeof(rem_addr));


    vector = ( int * ) malloc (sizeof ( int ) * SIZE);
	
    // Local Socket
    //fill out the socket's address information
    loc_port = atoi(argv[1]);
    loc_addr.sin_family = AF_INET;
    loc_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    loc_addr.sin_port = htons(loc_port);

    // Remote machine host
    host = argv[2];
    phost = gethostbyname(host);

    // Remote Socket
    //fill out the socket's address information
    rem_port = atoi(argv[3]);
    rem_addr.sin_family = AF_INET;
    rem_addr.sin_port = htons(rem_port);
    dsr = socket (AF_INET, SOCK_STREAM, 0);
	
    memcpy(&rem_addr.sin_addr, phost->h_addr, phost->h_length);

    // get the host name
    gethostname(host, 50);

    // create the socket	
    S0 = socket(AF_INET, SOCK_STREAM, 0);

    if (S0 < 0)
    { perror("Creating local stream socket"); exit(1); }

    //bind the socket into its address 	
    if (bind(S0, (struct sockaddr*) &loc_addr, sizeof(loc_addr)) < 0)
    { perror("Binding stream socket"); exit(1); }

    // Listen for conetions
    listen(S0, 1);

    // accept a connection
    S1 = accept(S0, (struct sockaddr*) 0, (int*) 0);

    if (dsr < 0)
    { perror("Creating remote stream socket"); exit(1); }

    //make the connection
    if (connect(dsr, (struct sockaddr*) &rem_addr, sizeof(rem_addr)) < 0)
    { perror("Conecting stream socket"); exit(1); }

//--------------------------------------------------------------------------------------------
// receive and send messages
    recv(S1, vector, SIZE, 0);
    printf ("Message passing on node [%s]\n", host);
    send(dsr, vector, SIZE , 0);
//--------------------------------------------------------------------------------------------

//close the connection
    close(dsr);
    close(S0);
    close(S1);

}

//############################################################################################