1 /*- 2 * Copyright (c) 2000 Alfred Perlstein <alfred@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #define ACCEPT_FILTER_MOD 31 32 #include <sys/param.h> 33 #include <sys/kernel.h> 34 #include <sys/module.h> 35 #include <sys/sysctl.h> 36 #include <sys/signalvar.h> 37 #include <sys/socketvar.h> 38 39 /* accept filter that holds a socket until data arrives */ 40 41 static int sohasdata(struct socket *so, void *arg, int waitflag); 42 43 static struct accept_filter accf_data_filter = { 44 "dataready", 45 sohasdata, 46 NULL, 47 NULL 48 }; 49 50 static moduledata_t accf_data_mod = { 51 "accf_data", 52 accept_filt_generic_mod_event, 53 &accf_data_filter 54 }; 55 56 DECLARE_MODULE(accf_data, accf_data_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE); 57 58 static int 59 sohasdata(struct socket *so, void *arg, int waitflag) 60 { 61 62 if (!soreadable(so)) 63 return (SU_OK); 64 65 return (SU_ISCONNECTED); 66 } 67