memcheck/tests/sendmsg.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include <sys/types.h>
   5 #include <sys/socket.h>
   6 #include <netinet/in.h>
   7 #include <netinet/ip.h>
   8
   9 #define PORT 12345
  10
  11 int
  12 main (int argc, char **argv)
  13 {
  14   int fd;
  15   struct sockaddr_in sa;
  16   struct msghdr msg;
  17   struct iovec iov[2];
  18
  19   fd = socket (AF_INET, SOCK_DGRAM, 0);
  20   if (fd == -1)
  21     {
  22       perror ("socket()");
  23       exit (EXIT_FAILURE);
  24     }
  25
  26   sa.sin_family = AF_INET;
  27   sa.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
  28   sa.sin_port = htons (PORT);
  29   if (connect (fd, (struct sockaddr *) &sa, sizeof (sa)) == -1)
  30     {
  31       perror ("connect ()");
  32       exit (EXIT_FAILURE);
  33     }
  34
  35   // Create msg_hdr. Oops, we forget to set msg_name...
  36   msg.msg_namelen = 0;
  37   iov[0].iov_base = "one";
  38   iov[0].iov_len = 3;
  39   iov[1].iov_base = "two";
  40   iov[1].iov_len = 3;
  41   msg.msg_iov = &iov[0];
  42   msg.msg_iovlen = 2;
  43   msg.msg_control = NULL;
  44   msg.msg_controllen = 0;
  45
  46   size_t s = sendmsg (fd, &msg, 0);
  47
  48   // Note how we now do set msg_name, but don't set msg_flags.
  49   // The msg_flags field is ignored by sendmsg.
  50   msg.msg_name = NULL;
  51
  52   fd = socket (AF_INET, SOCK_DGRAM, 0);
  53   if (fd == -1)
  54     {
  55       perror ("socket()");
  56       exit (EXIT_FAILURE);
  57     }
  58
  59   if (connect (fd, (struct sockaddr *) &sa, sizeof (sa)) == -1)
  60     {
  61       perror ("connect ()");
  62       exit (EXIT_FAILURE);
  63     }
  64
  65   s = sendmsg (fd, &msg, 0);
  66   if (s == -1)
  67     {
  68       perror ("sendmsg ()");
  69       exit (EXIT_FAILURE);
  70     }
  71   else
  72     fprintf (stderr, "sendmsg: %d\n", (int) s);
  73
  74   return 0;
  75 }