3 * Copyright (C) 2001-2003 Simone Piccardi
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or (at
8 * your option) any later version.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 /****************************************************************
22 * Simple TCP client for echo service (port 7)
24 * Author: Simone Piccardi
27 * Usage: echo -h give all info's
29 ****************************************************************/
31 * Include needed headers
33 #include <sys/types.h> /* primitive system data types */
34 #include <unistd.h> /* unix standard library */
35 #include <arpa/inet.h> /* IP addresses conversion utilities */
36 #include <sys/socket.h> /* socket constants, types and functions */
37 #include <stdio.h> /* standard I/O library */
38 #include <errno.h> /* error definitions and routines */
39 #include <string.h> /* C strings library */
40 #include <stdlib.h> /* C standard library */
41 #include <netinet/tcp.h> /* TCP constants and types */
43 /* still not defined in some include, because too new ... */
44 #ifndef TCP_CONGESTION
45 #define TCP_CONGESTION 13
53 void ClientEcho(FILE * filein, int socket);
54 void SigTERM_hand(int sig);
57 int main(int argc, char *argv[])
60 * Variables definition
69 * Input section: decode parameters passed in the calling
72 opterr = 0; /* don't want writing to stderr */
73 while ( (i = getopt(argc, argv, "hrv")) != -1) {
79 printf("Wrong -h option use\n");
89 case '?': /* unrecognized options */
90 printf("Unrecognized options -%c\n",optopt);
92 default: /* should not reached */
96 /* ***********************************************************
98 * Options processing completed
100 * Main code beginning
102 * ***********************************************************/
103 /* call sockconn to get a connected socket */
104 if ( (sock = sockconn(argv[optind], "echo", 6, SOCK_STREAM)) < 0) {
105 if (errno) perror("Socket creation error");
108 /* print some info about the socket, used to test some TCP_* options */
110 len = sizeof(buffer);
111 if (getsockopt(sock, SOL_TCP, TCP_CONGESTION, buffer, &len) < 0) {
112 perror("Cannot read congestion algorithm");
115 printf("Congestion algorithm %s\n", buffer);
118 /* check if resetting on close is required */
120 printf("Setting reset on close \n");
123 if (setsockopt(sock, SOL_SOCKET, SO_LINGER, &ling, sizeof(ling))) {
124 perror("Cannot set linger");
128 /* do read/write operations */
129 ClientEcho(stdin, sock);
134 * routine to print usage info and exit
137 printf("Take daytime from a remote host \n");
139 printf(" daytime [-h] [-v] [host in dotted decimal form] \n");
140 // printf(" -v set verbosity on\n");
141 printf(" -r require reset on closing\n");
142 printf(" -h print this help\n");
146 void ClientEcho(FILE * filein, int socket)
148 char sendbuff[MAXLINE+1], recvbuff[MAXLINE+1];
153 /* initialize file descriptor set */
155 maxfd = max(fileno(filein), socket) + 1;
157 FD_SET(socket, &fset); /* set for the socket */
159 FD_SET(fileno(filein), &fset); /* set for the standard input */
161 select(maxfd, &fset, NULL, NULL, NULL); /* wait for read ready */
162 if (FD_ISSET(fileno(filein), &fset)) { /* if ready on stdin */
163 if (fgets(sendbuff, MAXLINE, filein) == NULL) { /* if no input */
164 eof = 1; /* EOF on input */
165 shutdown(socket, SHUT_WR); /* close write half */
166 FD_CLR(fileno(filein), &fset); /* no more interest on stdin */
167 } else { /* else we have to write to socket */
168 nwrite = FullWrite(socket, sendbuff, strlen(sendbuff));
169 if (nwrite < 0) { /* on error stop */
170 printf("Errore in scrittura: %s", strerror(errno));
175 if (FD_ISSET(socket, &fset)) { /* if ready on socket */
176 nread = read(socket, recvbuff, strlen(sendbuff)); /* do read */
177 if (nread < 0) { /* error condition, stop client */
178 printf("Errore in lettura: %s\n", strerror(errno));
181 if (nread == 0) { /* server closed connection, stop */
185 printf("EOF prematuro sul socket\n");
189 recvbuff[nread] = 0; /* else read is ok, write on stdout */
190 if (fputs(recvbuff, stdout) == EOF) {
191 perror("Errore in scrittura su terminale");