1*22ce4affSfengbojiang /*- 2*22ce4affSfengbojiang * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3*22ce4affSfengbojiang * 4*22ce4affSfengbojiang * Copyright (c) 1999 Michael Smith <[email protected]> 5*22ce4affSfengbojiang * All rights reserved. 6*22ce4affSfengbojiang * 7*22ce4affSfengbojiang * Redistribution and use in source and binary forms, with or without 8*22ce4affSfengbojiang * modification, are permitted provided that the following conditions 9*22ce4affSfengbojiang * are met: 10*22ce4affSfengbojiang * 1. Redistributions of source code must retain the above copyright 11*22ce4affSfengbojiang * notice, this list of conditions and the following disclaimer. 12*22ce4affSfengbojiang * 2. Redistributions in binary form must reproduce the above copyright 13*22ce4affSfengbojiang * notice, this list of conditions and the following disclaimer in the 14*22ce4affSfengbojiang * documentation and/or other materials provided with the distribution. 15*22ce4affSfengbojiang * 16*22ce4affSfengbojiang * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17*22ce4affSfengbojiang * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18*22ce4affSfengbojiang * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19*22ce4affSfengbojiang * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20*22ce4affSfengbojiang * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21*22ce4affSfengbojiang * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22*22ce4affSfengbojiang * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23*22ce4affSfengbojiang * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24*22ce4affSfengbojiang * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25*22ce4affSfengbojiang * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26*22ce4affSfengbojiang * SUCH DAMAGE. 27*22ce4affSfengbojiang * 28*22ce4affSfengbojiang * $FreeBSD$ 29*22ce4affSfengbojiang */ 30*22ce4affSfengbojiang 31*22ce4affSfengbojiang #ifndef _SYS__EVENTHANDLER_H_ 32*22ce4affSfengbojiang #define _SYS__EVENTHANDLER_H_ 33*22ce4affSfengbojiang 34*22ce4affSfengbojiang #include <sys/queue.h> 35*22ce4affSfengbojiang 36*22ce4affSfengbojiang struct eventhandler_entry { 37*22ce4affSfengbojiang TAILQ_ENTRY(eventhandler_entry) ee_link; 38*22ce4affSfengbojiang int ee_priority; 39*22ce4affSfengbojiang #define EHE_DEAD_PRIORITY (-1) 40*22ce4affSfengbojiang void *ee_arg; 41*22ce4affSfengbojiang }; 42*22ce4affSfengbojiang 43*22ce4affSfengbojiang typedef struct eventhandler_entry *eventhandler_tag; 44*22ce4affSfengbojiang 45*22ce4affSfengbojiang /* 46*22ce4affSfengbojiang * You can optionally use the EVENTHANDLER_LIST and EVENTHANDLER_DIRECT macros 47*22ce4affSfengbojiang * to pre-define a symbol for the eventhandler list. This symbol can be used by 48*22ce4affSfengbojiang * EVENTHANDLER_DIRECT_INVOKE, which has the advantage of not needing to do a 49*22ce4affSfengbojiang * locked search of the global list of eventhandler lists. At least 50*22ce4affSfengbojiang * EVENTHANDLER_LIST_DEFINE must be be used for EVENTHANDLER_DIRECT_INVOKE to 51*22ce4affSfengbojiang * work. EVENTHANDLER_LIST_DECLARE is only needed if the call to 52*22ce4affSfengbojiang * EVENTHANDLER_DIRECT_INVOKE is in a different compilation unit from 53*22ce4affSfengbojiang * EVENTHANDLER_LIST_DEFINE. If the events are even relatively high frequency 54*22ce4affSfengbojiang * it is suggested that you directly define a list for them. 55*22ce4affSfengbojiang */ 56*22ce4affSfengbojiang struct eventhandler_list; 57*22ce4affSfengbojiang #define EVENTHANDLER_LIST_DECLARE(name) \ 58*22ce4affSfengbojiang extern struct eventhandler_list *_eventhandler_list_ ## name \ 59*22ce4affSfengbojiang 60*22ce4affSfengbojiang /* 61*22ce4affSfengbojiang * Event handlers need to be declared, but do not need to be defined. The 62*22ce4affSfengbojiang * declaration must be in scope wherever the handler is to be invoked. 63*22ce4affSfengbojiang */ 64*22ce4affSfengbojiang #define EVENTHANDLER_DECLARE(name, type) \ 65*22ce4affSfengbojiang struct eventhandler_entry_ ## name \ 66*22ce4affSfengbojiang { \ 67*22ce4affSfengbojiang struct eventhandler_entry ee; \ 68*22ce4affSfengbojiang type eh_func; \ 69*22ce4affSfengbojiang }; \ 70*22ce4affSfengbojiang struct __hack 71*22ce4affSfengbojiang 72*22ce4affSfengbojiang #endif 73