xref: /f-stack/freebsd/netinet/accf_data.c (revision 22ce4aff)
1a9643ea8Slogwang /*-
2*22ce4affSfengbojiang  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3*22ce4affSfengbojiang  *
4a9643ea8Slogwang  * Copyright (c) 2000 Alfred Perlstein <[email protected]>
5a9643ea8Slogwang  * All rights reserved.
6a9643ea8Slogwang  *
7a9643ea8Slogwang  * Redistribution and use in source and binary forms, with or without
8a9643ea8Slogwang  * modification, are permitted provided that the following conditions
9a9643ea8Slogwang  * are met:
10a9643ea8Slogwang  * 1. Redistributions of source code must retain the above copyright
11a9643ea8Slogwang  *    notice, this list of conditions and the following disclaimer.
12a9643ea8Slogwang  * 2. Redistributions in binary form must reproduce the above copyright
13a9643ea8Slogwang  *    notice, this list of conditions and the following disclaimer in the
14a9643ea8Slogwang  *    documentation and/or other materials provided with the distribution.
15a9643ea8Slogwang  *
16a9643ea8Slogwang  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17a9643ea8Slogwang  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18a9643ea8Slogwang  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19a9643ea8Slogwang  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20a9643ea8Slogwang  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21a9643ea8Slogwang  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22a9643ea8Slogwang  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23a9643ea8Slogwang  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24a9643ea8Slogwang  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25a9643ea8Slogwang  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26a9643ea8Slogwang  * SUCH DAMAGE.
27a9643ea8Slogwang  */
28a9643ea8Slogwang 
29a9643ea8Slogwang #include <sys/cdefs.h>
30a9643ea8Slogwang __FBSDID("$FreeBSD$");
31a9643ea8Slogwang 
32a9643ea8Slogwang #define ACCEPT_FILTER_MOD
33a9643ea8Slogwang 
34a9643ea8Slogwang #include <sys/param.h>
35a9643ea8Slogwang #include <sys/kernel.h>
36a9643ea8Slogwang #include <sys/module.h>
37a9643ea8Slogwang #include <sys/sysctl.h>
38a9643ea8Slogwang #include <sys/signalvar.h>
39a9643ea8Slogwang #include <sys/socketvar.h>
40a9643ea8Slogwang 
41a9643ea8Slogwang /* accept filter that holds a socket until data arrives */
42a9643ea8Slogwang 
43a9643ea8Slogwang static int	sohasdata(struct socket *so, void *arg, int waitflag);
44a9643ea8Slogwang 
45*22ce4affSfengbojiang ACCEPT_FILTER_DEFINE(accf_data, "dataready", sohasdata, NULL, NULL, 1);
46a9643ea8Slogwang 
47a9643ea8Slogwang static int
sohasdata(struct socket * so,void * arg,int waitflag)48a9643ea8Slogwang sohasdata(struct socket *so, void *arg, int waitflag)
49a9643ea8Slogwang {
50a9643ea8Slogwang 
51a9643ea8Slogwang 	if (!soreadable(so))
52a9643ea8Slogwang 		return (SU_OK);
53a9643ea8Slogwang 
54a9643ea8Slogwang 	return (SU_ISCONNECTED);
55a9643ea8Slogwang }
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