test/udp/sendwildcard/udp_sendwildcard.c

   1 #include <sys/types.h>
   2 #include <sys/socket.h>
   3
   4 #include <arpa/inet.h>
   5 #include <netinet/in.h>
   6
   7 #include <err.h>
   8 #include <stdio.h>
   9 #include <stdint.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12 #include <unistd.h>
  13
  14 static void
  15 usage(const char *cmd)
  16 {
  17         fprintf(stderr, "%s -4 ip4 -p port [-r]\n", cmd);
  18         exit(1);
  19 }
  20
  21 int
  22 main(int argc, char *argv[])
  23 {
  24         struct sockaddr_in in;
  25         int s, opt, n, reuseport;
  26         uint8_t buf[18];
  27
  28         memset(&in, 0, sizeof(in));
  29         in.sin_family = AF_INET;
  30
  31         reuseport = 0;
  32
  33         while ((opt = getopt(argc, argv, "4:p:r")) != -1) {
  34                 switch (opt) {
  35                 case '4':
  36                         if (inet_pton(AF_INET, optarg, &in.sin_addr) <= 0)
  37                                 usage(argv[0]);
  38                         break;
  39
  40                 case 'p':
  41                         in.sin_port = strtol(optarg, NULL, 10);
  42                         in.sin_port = htons(in.sin_port);
  43                         break;
  44
  45                 case 'r':
  46                         reuseport = 1;
  47                         break;
  48
  49                 default:
  50                         usage(argv[0]);
  51                 }
  52         }
  53
  54         if (in.sin_addr.s_addr == INADDR_ANY || in.sin_port == 0)
  55                 usage(argv[0]);
  56
  57         s = socket(AF_INET, SOCK_DGRAM, 0);
  58         if (s < 0)
  59                 err(2, "socket failed");
  60
  61         if (reuseport) {
  62                 if (setsockopt(s, SOL_SOCKET, SO_REUSEPORT,
  63                     &reuseport, sizeof(reuseport)) < 0)
  64                         err(2, "setsockopt SO_REUSEPORT failed");
  65         }
  66
  67         n = sendto(s, buf, sizeof(buf), 0,
  68             (const struct sockaddr *)&in, sizeof(in));
  69         if (n < 0)
  70                 err(2, "sendto failed");
  71         else if (n != (int)sizeof(buf))
  72                 errx(2, "sent truncated data %d", n);
  73
  74         n = read(s, buf, sizeof(buf));
  75         if (n < 0)
  76                 err(2, "read failed");
  77         printf("read %d, done\n", n);
  78
  79         exit(0);
  80 }