xref: /netbsd-src/external/mpl/dhcp/bind/dist/lib/isc/event.c (revision 4afad4b7fa6d4a0d3dedf41d1587a7250710ae54)
1 /*	$NetBSD: event.c,v 1.1 2024/02/18 20:57:49 christos Exp $	*/
2 
3 /*
4  * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
5  *
6  * SPDX-License-Identifier: MPL-2.0
7  *
8  * This Source Code Form is subject to the terms of the Mozilla Public
9  * License, v. 2.0. If a copy of the MPL was not distributed with this
10  * file, you can obtain one at https://mozilla.org/MPL/2.0/.
11  *
12  * See the COPYRIGHT file distributed with this work for additional
13  * information regarding copyright ownership.
14  */
15 
16 /*!
17  * \file
18  */
19 
20 #include <isc/event.h>
21 #include <isc/mem.h>
22 #include <isc/util.h>
23 
24 /***
25  *** Events.
26  ***/
27 
28 static void
destroy(isc_event_t * event)29 destroy(isc_event_t *event) {
30 	isc_mem_t *mctx = event->ev_destroy_arg;
31 
32 	isc_mem_put(mctx, event, event->ev_size);
33 }
34 
35 isc_event_t *
isc_event_allocate(isc_mem_t * mctx,void * sender,isc_eventtype_t type,isc_taskaction_t action,void * arg,size_t size)36 isc_event_allocate(isc_mem_t *mctx, void *sender, isc_eventtype_t type,
37 		   isc_taskaction_t action, void *arg, size_t size) {
38 	isc_event_t *event;
39 
40 	REQUIRE(size >= sizeof(struct isc_event));
41 	REQUIRE(action != NULL);
42 
43 	event = isc_mem_get(mctx, size);
44 
45 	ISC_EVENT_INIT(event, size, 0, NULL, type, action, arg, sender, destroy,
46 		       mctx);
47 
48 	return (event);
49 }
50 
51 isc_event_t *
isc_event_constallocate(isc_mem_t * mctx,void * sender,isc_eventtype_t type,isc_taskaction_t action,const void * arg,size_t size)52 isc_event_constallocate(isc_mem_t *mctx, void *sender, isc_eventtype_t type,
53 			isc_taskaction_t action, const void *arg, size_t size) {
54 	isc_event_t *event;
55 	void *deconst_arg;
56 
57 	REQUIRE(size >= sizeof(struct isc_event));
58 	REQUIRE(action != NULL);
59 
60 	event = isc_mem_get(mctx, size);
61 
62 	/*
63 	 * Removing the const attribute from "arg" is the best of two
64 	 * evils here.  If the event->ev_arg member is made const, then
65 	 * it affects a great many users of the task/event subsystem
66 	 * which are not passing in an "arg" which starts its life as
67 	 * const.  Changing isc_event_allocate() and isc_task_onshutdown()
68 	 * to not have "arg" prototyped as const (which is quite legitimate,
69 	 * because neither of those functions modify arg) can cause
70 	 * compiler whining anytime someone does want to use a const
71 	 * arg that they themselves never modify, such as with
72 	 * gcc -Wwrite-strings and using a string "arg".
73 	 */
74 	DE_CONST(arg, deconst_arg);
75 
76 	ISC_EVENT_INIT(event, size, 0, NULL, type, action, deconst_arg, sender,
77 		       destroy, mctx);
78 
79 	return (event);
80 }
81 
82 void
isc_event_free(isc_event_t ** eventp)83 isc_event_free(isc_event_t **eventp) {
84 	isc_event_t *event;
85 
86 	REQUIRE(eventp != NULL);
87 	event = *eventp;
88 	*eventp = NULL;
89 	REQUIRE(event != NULL);
90 
91 	REQUIRE(!ISC_LINK_LINKED(event, ev_link));
92 	REQUIRE(!ISC_LINK_LINKED(event, ev_ratelink));
93 
94 	if (event->ev_destroy != NULL) {
95 		(event->ev_destroy)(event);
96 	}
97 }
98