gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) sd);

do
{
ret = gnutls_handshake (session);
}
while (ret < 0 && gnutls_error_is_fatal (ret) == 0);

if (ret < 0)
{
close (sd);
gnutls_deinit (session);
fprintf (stderr, "*** Handshake has failed (%s)\n\n",
gnutls_strerror (ret));
continue;
}
printf ("- Handshake was completed\n");

/* see the Getting peer's information example */
/* print_info(session); */

for (;;)
{
memset (buffer, 0, MAX_BUF + 1);
ret = gnutls_record_recv (session, buffer, MAX_BUF);

if (ret == 0)
{
printf ("\n- Peer has closed the GnuTLS connection\n");
break;
}
else if (ret < 0)
{
fprintf (stderr, "\n*** Received corrupted "
"data(%d). Closing the connection.\n\n", ret);
break;
}
else if (ret > 0)
{
/* echo data back to the client
*/
printf("Server receives a packet with content:%s\n", buffer);
gnutls_record_send (session, buffer, strlen (buffer));
}
}
printf ("\n");
/* do not wait for the peer to close the connection.
*/
gnutls_bye (session, GNUTLS_SHUT_WR);

close (sd);
gnutls_deinit (session);

}
close (listen_sd);

gnutls_certificate_free_credentials (x509_cred);
gnutls_priority_deinit (priority_cache);

gnutls_global_deinit ();

return 0;

}

相关阅读：