2 * Copyright (c) 1999 Michael Smith <msmith@freebsd.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
29 #include <sys/queue.h>
31 #ifndef SYS_EVENTHANDLER_H
32 #define SYS_EVENTHANDLER_H
34 struct eventhandler_entry
36 TAILQ_ENTRY(eventhandler_entry) ee_link;
41 struct eventhandler_list
43 TAILQ_ENTRY(eventhandler_list) el_link;
46 #define EHE_INITTED (1<<0)
47 TAILQ_HEAD(,eventhandler_entry) el_entries;
50 typedef struct eventhandler_entry *eventhandler_tag;
53 * Fast handler lists require the eventhandler list be present
54 * at link time. They don't allow addition of entries to
55 * unknown eventhandler lists, ie. each list must have an
58 * Fast handler lists must be defined once by the owner
59 * of the eventhandler list, and the declaration must be in
60 * scope at any point the list is manipulated.
62 #define EVENTHANDLER_FAST_DECLARE(name, type) \
63 extern struct eventhandler_list Xeventhandler_list_ ## name ; \
64 struct eventhandler_entry_ ## name \
66 struct eventhandler_entry ee; \
70 #define EVENTHANDLER_FAST_DEFINE(name, type) \
71 struct eventhandler_list Xeventhandler_list_ ## name = { #name };
73 #define EVENTHANDLER_FAST_INVOKE(name, args...) \
75 struct eventhandler_list *_el = &Xeventhandler_list_ ## name ; \
76 struct eventhandler_entry *_ep = TAILQ_FIRST(&(_el->el_entries)); \
78 while (_ep != NULL) { \
79 ((struct eventhandler_entry_ ## name *)_ep)->eh_func(_ep->ee_arg , ## args); \
80 _ep = TAILQ_NEXT(_ep, ee_link); \
84 #define EVENTHANDLER_FAST_REGISTER(name, func, arg, priority) \
85 eventhandler_register(Xeventhandler_list_ ## name, #name, func, arg, priority)
87 #define EVENTHANDLER_FAST_DEREGISTER(name, tag) \
88 eventhandler_deregister(Xeventhandler_list ## name, tag)
92 * Slow handlerss are entirely dynamic; lists are created
93 * when entries are added to them, and thus have no concept of "owner",
95 * Slow handlerss need to be declared, but do not need to be defined. The
96 * declaration must be in scope wherever the handler is to be invoked.
98 #define EVENTHANDLER_DECLARE(name, type) \
99 struct eventhandler_entry_ ## name \
101 struct eventhandler_entry ee; \
105 #define EVENTHANDLER_INVOKE(name, args...) \
107 struct eventhandler_list *_el; \
108 struct eventhandler_entry *_ep; \
110 if ((_el = eventhandler_find_list(#name)) != NULL) { \
111 for (_ep = TAILQ_FIRST(&(_el->el_entries)); \
113 _ep = TAILQ_NEXT(_ep, ee_link)) { \
114 ((struct eventhandler_entry_ ## name *)_ep)->eh_func(_ep->ee_arg , ## args); \
119 #define EVENTHANDLER_REGISTER(name, func, arg, priority) \
120 eventhandler_register(NULL, #name, func, arg, priority)
122 #define EVENTHANDLER_DEREGISTER(name, tag) \
124 struct eventhandler_list *_el; \
126 if ((_el = eventhandler_find_list(#name)) != NULL) \
127 eventhandler_deregister(_el, tag); \
131 extern eventhandler_tag eventhandler_register(struct eventhandler_list *list,
136 extern void eventhandler_deregister(struct eventhandler_list *list,
137 eventhandler_tag tag);
138 extern struct eventhandler_list *eventhandler_find_list(char *name);
141 * Standard system event queues.
144 /* Shutdown events */
145 typedef void (*shutdown_fn) __P((void *, int));
147 #define SHUTDOWN_PRI_FIRST 0
148 #define SHUTDOWN_PRI_DEFAULT 10000
149 #define SHUTDOWN_PRI_LAST 20000
151 EVENTHANDLER_DECLARE(shutdown_pre_sync, shutdown_fn); /* before fs sync */
152 EVENTHANDLER_DECLARE(shutdown_post_sync, shutdown_fn); /* after fs sync */
153 EVENTHANDLER_DECLARE(shutdown_final, shutdown_fn);
155 #endif /* SYS_EVENTHANDLER_H */