lib/ip/socket.c

   1 #include <errno.h>
   2 #include <fcntl.h>
   3 #include <signal.h>
   4 #include <stdio.h>
   5 #include <unistd.h>
   6 #include <sys/socket.h>
   7
   8 #include <net/netlib.h>
   9 #include <netinet/in.h>
  10
  11 #define DEBUG 0
  12
  13 static int _tcp_socket(int protocol);
  14 static int _udp_socket(int protocol);
  15
  16 int socket(int domain, int type, int protocol)
  17 {
  18 #if DEBUG
  19         fprintf(stderr, "socket: domain %d, type %d, protocol %d\n",
  20                 domain, type, protocol);
  21 #endif
  22         if (domain != AF_INET)
  23         {
  24 #if DEBUG
  25                 fprintf(stderr, "socket: bad domain %d\n", domain);
  26 #endif
  27                 errno= EAFNOSUPPORT;
  28                 return -1;
  29         }
  30         if (type == SOCK_STREAM)
  31                 return _tcp_socket(protocol);
  32
  33         if (type == SOCK_DGRAM)
  34                 return _udp_socket(protocol);
  35
  36 #if DEBUG
  37         fprintf(stderr, "socket: nothing for domain %d, type %d, protocol %d\n",
  38                 domain, type, protocol);
  39 #endif
  40         errno= EPROTOTYPE;
  41         return -1;
  42 }
  43
  44 static int _tcp_socket(int protocol)
  45 {
  46         int fd;
  47         if (protocol != 0 && protocol != IPPROTO_TCP)
  48         {
  49 #if DEBUG
  50                 fprintf(stderr, "socket(tcp): bad protocol %d\n", protocol);
  51 #endif
  52                 errno= EPROTONOSUPPORT;
  53                 return -1;
  54         }
  55         fd= open(TCP_DEVICE, O_RDWR);
  56         return fd;
  57 }
  58
  59 static int _udp_socket(int protocol)
  60 {
  61         int r, fd, t_errno;
  62         struct sockaddr_in sin;
  63
  64         if (protocol != 0 && protocol != IPPROTO_UDP)
  65         {
  66 #if DEBUG
  67                 fprintf(stderr, "socket(udp): bad protocol %d\n", protocol);
  68 #endif
  69                 errno= EPROTONOSUPPORT;
  70                 return -1;
  71         }
  72         fd= open(UDP_DEVICE, O_RDWR);
  73         if (fd == -1)
  74                 return fd;
  75
  76         /* Bind is implict for UDP sockets? */
  77         sin.sin_family= AF_INET;
  78         sin.sin_addr.s_addr= INADDR_ANY;
  79         sin.sin_port= 0;
  80         r= bind(fd, (struct sockaddr *)&sin, sizeof(sin));
  81         if (r != 0)
  82         {
  83                 t_errno= errno;
  84                 close(fd);
  85                 errno= t_errno;
  86                 return -1;
  87         }
  88         return fd;
  89 }
  90