tun-device: Remove the superfluous use of select() before read()
[strongswan.git] / src / libstrongswan / networking / tun_device.c
index ff2c4a3..035b846 100644 (file)
@@ -347,31 +347,20 @@ METHOD(tun_device_t, read_packet, bool,
        private_tun_device_t *this, chunk_t *packet)
 {
        ssize_t len;
-       fd_set set;
        bool old;
 
-       FD_ZERO(&set);
-       FD_SET(this->tunfd, &set);
+       *packet = chunk_alloc(get_mtu(this));
 
+       thread_cleanup_push(free, packet->ptr);
        old = thread_cancelability(TRUE);
-       len = select(this->tunfd + 1, &set, NULL, NULL, NULL);
-       thread_cancelability(old);
-
-       if (len < 0)
-       {
-               DBG1(DBG_LIB, "select on TUN device %s failed: %s", this->if_name,
-                        strerror(errno));
-               return FALSE;
-       }
-       /* FIXME: this is quite expensive for lots of small packets, copy from
-        * local buffer instead? */
-       *packet = chunk_alloc(get_mtu(this));
        len = read(this->tunfd, packet->ptr, packet->len);
+       thread_cancelability(old);
+       thread_cleanup_pop(FALSE);
        if (len < 0)
        {
                DBG1(DBG_LIB, "reading from TUN device %s failed: %s", this->if_name,
                         strerror(errno));
-               chunk_free(packet);
+               free(packet->ptr);
                return FALSE;
        }
        packet->len = len;