test/select/test06_cli.c

   1 /*
   2  * Test name: test06_cli.c
   3  *
   4  * Objective: Test a simple TCP client
   5  *
   6  * Description: Implements a simple echo client using the TCP protocol. First
   7  * it waits until it is possible to write (which is always).
   8  */
   9
  10 #include <sys/types.h>
  11 #include <sys/ioctl.h>
  12 #include <sys/select.h>
  13 #include <stdio.h>
  14 #include <string.h>
  15 #include <stdlib.h>
  16 #include <stdarg.h>
  17 #include <fcntl.h>
  18 #include <errno.h>
  19 #include <unistd.h>
  20 #include <net/netlib.h>
  21 #include <net/gen/netdb.h>
  22 #include <net/gen/in.h>
  23 #include <net/gen/tcp.h>
  24 #include <net/gen/tcp_io.h>
  25 #include <net/hton.h>
  26
  27 #define PORT 6060L
  28
  29 int tcp_connect(char *host, long port)
  30 {
  31   /* creates a tcp connection with specified host and port */
  32   char *tcp_device;
  33   struct hostent *hp;
  34   int netfd;
  35   nwio_tcpcl_t tcpcopt;
  36   nwio_tcpconf_t tcpconf;
  37   ipaddr_t dirhost;
  38   int tries;
  39   int result;
  40
  41   /* get host address */
  42   if ((hp = gethostbyname(host)) == (struct hostent*) NULL)
  43   {
  44     fprintf(stderr,"Unknown host\n");
  45     return(-1);
  46   }
  47   memcpy((char *)&dirhost, (char *)hp->h_addr, hp->h_length);
  48
  49   /* Get default TCP device */
  50   if (( tcp_device = getenv("TCP_DEVICE") ) == NULL)
  51     tcp_device = TCP_DEVICE;
  52
  53   /* Establish TCP connection */
  54   if ((netfd = open(tcp_device, O_RDWR)) < 0)
  55   {
  56     fprintf(stderr,"Error opening TCP device\n");
  57     return -1;
  58   }
  59
  60   /* Configure TCP connection */
  61   tcpconf.nwtc_flags=NWTC_LP_SEL | NWTC_SET_RA | NWTC_SET_RP;
  62   tcpconf.nwtc_remaddr = dirhost;
  63   tcpconf.nwtc_remport = (tcpport_t) htons(port);
  64
  65   if ((result = ioctl(netfd, NWIOSTCPCONF, &tcpconf) ) <0)
  66   {
  67     fprintf(stderr, "Error establishing communication\n");
  68     printf("Error:  %d\n",result);
  69     close(netfd);
  70     return -1;
  71   }
  72
  73   /* Get configuration for TCP comm */
  74   if ((result = ioctl(netfd, NWIOGTCPCONF, &tcpconf) ) < 0)
  75   {
  76     fprintf(stderr,"Error getting configuration\n");
  77     printf("Error: %d\n", result);
  78     close(netfd);
  79     return -1;
  80   }
  81
  82   /* Establish connection */
  83   tcpcopt.nwtcl_flags = 0;
  84   tries = 0;
  85   while (tries < 10) {
  86         if ( (result = ioctl(netfd, NWIOTCPCONN, &tcpcopt)) < 0 ) {
  87                 if (errno != EAGAIN)
  88                 {
  89                         fprintf(stderr, "Server is not listening\n");
  90                         close(netfd);
  91                         return(-1);
  92                 }
  93                 fprintf(stderr, "Unable to connect\n");
  94                 sleep(1);
  95                 tries++;
  96         }
  97         else
  98                 break;  /* Connection */
  99  }
 100  /* Check result value */
 101  if (result < 0) {
 102         fprintf(stderr, "Error connecting\n");
 103         fprintf(stderr, "Error: %d\n", result);
 104         printf("Number of tries: %d\n", tries);
 105         printf("Error: %d\n", errno);
 106         close(netfd);
 107         return -1;
 108  }
 109  return netfd;
 110 }
 111
 112 int main(int argc,char *argv[]) {
 113   int fd;
 114   ssize_t data_read;
 115   char send_buf[1024];
 116   char recv_buf[1024];
 117   fd_set fds_write;
 118   int ret;
 119
 120   /* Check parameters */
 121   if (argc !=2) {
 122     fprintf(stderr,"Usage: %s host\n", argv[0]);
 123     exit(-1);
 124   }
 125
 126   if ((fd = tcp_connect(argv[1], PORT) ) < 0)
 127     exit(-1);
 128   printf("Connected to server\n");
 129   /* init fd_set */
 130   FD_ZERO(&fds_write);
 131   FD_SET(fd, &fds_write);
 132   while (1)
 133   {
 134     /* Wait until it is possible to write with select */
 135     ret = select(4, NULL, &fds_write, NULL, NULL);
 136     if (ret < 0) {
 137         fprintf(stderr, "Error on select waiting for write: %d\n", errno);
 138         exit(-1);
 139     }
 140     if (!FD_ISSET(fd, &fds_write)) {
 141         fprintf(stderr, "Error: The net connection is not ready for writing (?)\n");
 142         exit(-1);
 143     }
 144
 145     /* Get a string and send it */
 146     printf("Ready to write...\n");
 147     printf("Send data: ");
 148     gets(send_buf);
 149     write(fd, &send_buf, strlen(send_buf)+1);
 150
 151     /* If data sent is exit then break */
 152     if (!strcmp(send_buf,"exit"))
 153       break;
 154
 155     /* Get server response */
 156     data_read = read(fd, &recv_buf, 1024);
 157     printf("Received: %s\n\n", recv_buf);
 158   }
 159
 160   /* Close TCP communication */
 161   close(fd);
 162 }