gcc/testsuite/gcc.dg/analyzer/fd-glibc-byte-stream-connection-server.c

   1 /* Example from glibc manual (16.9.7).  */
   2 /* { dg-require-effective-target sockets } */
   3 /* { dg-additional-options "-Wno-analyzer-too-complex" } */
   4 /* { dg-skip-if "" { hppa*-*-hpux* powerpc*-*-aix* } } */
   5
   6 #include <stdio.h>
   7 #include <errno.h>
   8 #include <stdlib.h>
   9 #include <unistd.h>
  10 #include <sys/types.h>
  11 #include <sys/socket.h>
  12 #include <netinet/in.h>
  13 #include <arpa/inet.h>
  14 #include <netdb.h>
  15
  16 #define PORT    5555
  17 #define MAXMSG  512
  18
  19 int
  20 make_socket (uint16_t port)
  21 {
  22   int sock;
  23   struct sockaddr_in name;
  24
  25   /* Create the socket. */
  26   sock = socket (PF_INET, SOCK_STREAM, 0);
  27   if (sock < 0)
  28     {
  29       perror ("socket");
  30       exit (EXIT_FAILURE);
  31     }
  32
  33   /* Give the socket a name. */
  34   name.sin_family = AF_INET;
  35   name.sin_port = htons (port);
  36   name.sin_addr.s_addr = htonl (INADDR_ANY);
  37   if (bind (sock, (struct sockaddr *) &name, sizeof (name)) < 0)
  38     {
  39       perror ("bind");
  40       exit (EXIT_FAILURE);
  41     }
  42
  43   return sock;
  44 }
  45
  46 int
  47 read_from_client (int filedes)
  48 {
  49   char buffer[MAXMSG];
  50   int nbytes;
  51
  52   nbytes = read (filedes, buffer, MAXMSG);
  53   if (nbytes < 0)
  54     {
  55       /* Read error. */
  56       perror ("read");
  57       exit (EXIT_FAILURE);
  58     }
  59   else if (nbytes == 0)
  60     /* End-of-file. */
  61     return -1;
  62   else
  63     {
  64       /* Data read. */
  65       fprintf (stderr, "Server: got message: `%s'\n", buffer);
  66       return 0;
  67     }
  68 }
  69
  70 int
  71 main (void)
  72 {
  73   int sock;
  74   fd_set active_fd_set, read_fd_set;
  75   int i;
  76   struct sockaddr_in clientname;
  77   socklen_t size;
  78
  79   /* Create the socket and set it up to accept connections. */
  80   sock = make_socket (PORT);
  81   if (listen (sock, 1) < 0)
  82     {
  83       perror ("listen");
  84       exit (EXIT_FAILURE);
  85     }
  86
  87   /* Initialize the set of active sockets. */
  88   FD_ZERO (&active_fd_set);
  89   FD_SET (sock, &active_fd_set);
  90
  91   while (1)
  92     {
  93       /* Block until input arrives on one or more active sockets. */
  94       read_fd_set = active_fd_set;
  95       if (select (FD_SETSIZE, &read_fd_set, NULL, NULL, NULL) < 0)
  96         {
  97           perror ("select");
  98           exit (EXIT_FAILURE);
  99         }
 100
 101       /* Service all the sockets with input pending. */
 102       for (i = 0; i < FD_SETSIZE; ++i)
 103         if (FD_ISSET (i, &read_fd_set))
 104           {
 105             if (i == sock)
 106               {
 107                 /* Connection request on original socket. */
 108                 int new;
 109                 size = sizeof (clientname);
 110                 new = accept (sock,
 111                               (struct sockaddr *) &clientname,
 112                               &size);
 113                 if (new < 0)
 114                   {
 115                     perror ("accept");
 116                     exit (EXIT_FAILURE);
 117                   }
 118                 fprintf (stderr,
 119                          "Server: connect from host %s, port %hd.\n",
 120                          inet_ntoa (clientname.sin_addr),
 121                          ntohs (clientname.sin_port));
 122                 FD_SET (new, &active_fd_set);
 123               }
 124             else
 125               {
 126                 /* Data arriving on an already-connected socket. */
 127                 if (read_from_client (i) < 0)
 128                   {
 129                     close (i);
 130                     FD_CLR (i, &active_fd_set);
 131                   }
 132               }
 133           }
 134     }
 135 }