126 lines
2.8 KiB
C
126 lines
2.8 KiB
C
/**
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* @section LICENSE
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation; either version 2 of the
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* License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details at
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* http://www.gnu.org/copyleft/gpl.html
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*
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* @section DESCRIPTION
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*
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* Simple program that creates an IPv4 TCP socket and tries to connect
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* to a remote host before sending a string to this host. The string,
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* IPv4 addr and port number of the remote host are passed as command
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* line parameters as follow:
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* ./pg_name IPv4_addr port_number string
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*/
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#include <sys/socket.h>
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#include <sys/types.h>
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#include <netinet/in.h>
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#include <sys/stat.h>
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#include <fcntl.h>
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#include <stdlib.h>
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#include <stdio.h>
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#include <string.h>
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#include <unistd.h>
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#include <arpa/inet.h>
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int setup_connection (char *str_serveraddr, char *str_port)
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{
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int sockfd;
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struct sockaddr_in server;
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socklen_t addrlen;
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// socket factory
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if ((sockfd = socket (AF_INET, SOCK_STREAM, IPPROTO_TCP)) == -1) {
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perror ("socket");
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exit (EXIT_FAILURE);
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}
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// init remote addr structure and other params
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server.sin_family = AF_INET;
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server.sin_port = htons (atoi (str_port));
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addrlen = sizeof (struct sockaddr_in);
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// get addr from command line and convert it
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if (inet_pton (AF_INET, str_serveraddr, &server.sin_addr) != 1) {
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perror ("inet_pton");
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close (sockfd);
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exit (EXIT_FAILURE);
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}
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printf ("Trying to connect to the remote host\n");
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if (connect (sockfd, (struct sockaddr *)&server, addrlen) == -1) {
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perror ("connect");
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exit (EXIT_FAILURE);
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}
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return sockfd;
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}
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int send_msg(int sockfd, char *message)
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{
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int ret;
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// send string
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if ((ret = send (sockfd, message, strlen (message), 0)) == -1) {
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perror ("send");
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close (sockfd);
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exit (EXIT_FAILURE);
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}
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return ret;
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}
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int recv_msg(int sockfd)
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{
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char buf[1024] = { 0 };
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int ret;
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// send string
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if ((ret = recv (sockfd, buf, sizeof(buf), 0)) == -1) {
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perror ("recv");
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close (sockfd);
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exit (EXIT_FAILURE);
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}
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printf ("message received: %s\n", buf);
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return ret;
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}
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int main (int argc, char **argv)
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{
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int sockfd;
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// check the number of args on command line
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if (argc != 4) {
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printf ("USAGE: %s @server port_num string\n", argv[0]);
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exit (-1);
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}
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sockfd = setup_connection(argv[1], argv[2]);
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printf ("Connection OK\n");
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send_msg (sockfd, argv[3]);
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send_msg (sockfd, argv[3]);
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send_msg (sockfd, argv[3]);
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send_msg (sockfd, argv[3]);
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send_msg (sockfd, argv[3]);
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recv_msg (sockfd);
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printf ("Disconnection\n");
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// close the socket
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close (sockfd);
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return 0;
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}
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