gcc/testsuite/c-c++-common/analyzer/fd-manpage-getaddrinfo-server.c

   1 /* Example from getaddrinfo.3 manpage, which has this license:
   2
   3 Copyright (c) 2007, 2008 Michael Kerrisk <mtk.manpages@gmail.com>
   4 and Copyright (c) 2006 Ulrich Drepper <drepper@redhat.com>
   5 A few pieces of an earlier version remain:
   6 Copyright 2000, Sam Varshavchik <mrsam@courier-mta.com>
   7
   8 Permission is granted to make and distribute verbatim copies of this
   9 manual provided the copyright notice and this permission notice are
  10 preserved on all copies.
  11
  12 Permission is granted to copy and distribute modified versions of this
  13 manual under the conditions for verbatim copying, provided that the
  14 entire resulting derived work is distributed under the terms of a
  15 permission notice identical to this one.
  16
  17 Since the Linux kernel and libraries are constantly changing, this
  18 manual page may be incorrect or out-of-date.  The author(s) assume no
  19 responsibility for errors or omissions, or for damages resulting from
  20 the use of the information contained herein.  The author(s) may not
  21 have taken the same level of care in the production of this manual,
  22 which is licensed free of charge, as they might when working
  23 professionally.
  24
  25 Formatted or processed versions of this manual, if unaccompanied by
  26 the source, must acknowledge the copyright and authors of this work.
  27 */
  28
  29 /* { dg-require-effective-target sockets } */
  30
  31 /* Needed on some targets until we have exception-handling working (PR 111475).  */
  32 /* { dg-additional-options "-fno-exceptions" } */
  33
  34 /* { dg-skip-if "" { hppa*-*-hpux* powerpc*-*-aix* } } */
  35
  36 #include <sys/types.h>
  37 #include <stdio.h>
  38 #include <stdlib.h>
  39 #include <unistd.h>
  40 #include <string.h>
  41 #include <sys/socket.h>
  42 #include <netdb.h>
  43
  44 #define BUF_SIZE 500
  45
  46 int
  47 main(int argc, char *argv[])
  48 {
  49   struct addrinfo hints;
  50   struct addrinfo *result, *rp;
  51   int sfd, s;
  52   struct sockaddr_storage peer_addr;
  53   socklen_t peer_addr_len;
  54   ssize_t nread;
  55   char buf[BUF_SIZE];
  56
  57   if (argc != 2) {
  58     fprintf(stderr, "Usage: %s port\n", argv[0]);
  59     exit(EXIT_FAILURE);
  60   }
  61
  62   memset(&hints, 0, sizeof(hints));
  63   hints.ai_family = AF_UNSPEC;    /* Allow IPv4 or IPv6 */
  64   hints.ai_socktype = SOCK_DGRAM; /* Datagram socket */
  65   hints.ai_flags = AI_PASSIVE;    /* For wildcard IP address */
  66   hints.ai_protocol = 0;          /* Any protocol */
  67   hints.ai_canonname = NULL;
  68   hints.ai_addr = NULL;
  69   hints.ai_next = NULL;
  70
  71   s = getaddrinfo(NULL, argv[1], &hints, &result);
  72   if (s != 0) {
  73     fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(s));
  74     exit(EXIT_FAILURE);
  75   }
  76
  77   /* getaddrinfo() returns a list of address structures.
  78      Try each address until we successfully bind(2).
  79      If socket(2) (or bind(2)) fails, we (close the socket
  80      and) try the next address. */
  81
  82   for (rp = result; rp != NULL; rp = rp->ai_next) {
  83     sfd = socket(rp->ai_family, rp->ai_socktype,
  84                  rp->ai_protocol);
  85     if (sfd == -1)
  86       continue;
  87
  88     if (bind(sfd, rp->ai_addr, rp->ai_addrlen) == 0)
  89       break;                  /* Success */
  90
  91     close(sfd);
  92   }
  93
  94   freeaddrinfo(result);           /* No longer needed */
  95
  96   if (rp == NULL) {               /* No address succeeded */
  97     fprintf(stderr, "Could not bind\n");
  98     exit(EXIT_FAILURE);
  99   }
 100
 101   /* Read datagrams and echo them back to sender. */
 102
 103   for (;;) {
 104     peer_addr_len = sizeof(peer_addr);
 105     nread = recvfrom(sfd, buf, BUF_SIZE, 0,
 106                      (struct sockaddr *) &peer_addr, &peer_addr_len);
 107     if (nread == -1)
 108       continue;               /* Ignore failed request */
 109
 110     char host[NI_MAXHOST], service[NI_MAXSERV];
 111
 112     s = getnameinfo((struct sockaddr *) &peer_addr,
 113                     peer_addr_len, host, NI_MAXHOST,
 114                     service, NI_MAXSERV, NI_NUMERICSERV);
 115     if (s == 0)
 116       printf("Received %zd bytes from %s:%s\n",
 117              nread, host, service);
 118     else
 119       fprintf(stderr, "getnameinfo: %s\n", gai_strerror(s));
 120
 121     if (sendto(sfd, buf, nread, 0,
 122                (struct sockaddr *) &peer_addr,
 123                peer_addr_len) != nread)
 124       fprintf(stderr, "Error sending response\n");
 125   }
 126 }