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