external/bsd/bind/dist/lib/isc/event.c

   1 /*      $NetBSD: event.c,v 1.5 2014/12/10 04:37:59 christos Exp $       */
   2
   3 /*
   4  * Copyright (C) 2004, 2005, 2007, 2014  Internet Systems Consortium, Inc. ("ISC")
   5  * Copyright (C) 1998-2001  Internet Software Consortium.
   6  *
   7  * Permission to use, copy, modify, and/or distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  12  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  13  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  14  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  15  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  16  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  17  * PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 /* Id: event.c,v 1.21 2007/06/19 23:47:17 tbox Exp  */
  21
  22 /*!
  23  * \file
  24  * \author Principal Author: Bob Halley
  25  */
  26
  27 #include <config.h>
  28
  29 #include <isc/event.h>
  30 #include <isc/mem.h>
  31 #include <isc/util.h>
  32
  33 /***
  34  *** Events.
  35  ***/
  36
  37 static void
  38 destroy(isc_event_t *event) {
  39         isc_mem_t *mctx = event->ev_destroy_arg;
  40
  41         isc_mem_put(mctx, event, event->ev_size);
  42 }
  43
  44 isc_event_t *
  45 isc_event_allocate(isc_mem_t *mctx, void *sender, isc_eventtype_t type,
  46                    isc_taskaction_t action, void *arg, size_t size)
  47 {
  48         isc_event_t *event;
  49
  50         REQUIRE(size >= sizeof(struct isc_event));
  51         REQUIRE(action != NULL);
  52
  53         event = isc_mem_get(mctx, size);
  54         if (event == NULL)
  55                 return (NULL);
  56
  57         ISC_EVENT_INIT(event, size, 0, NULL, type, action, arg,
  58                        sender, destroy, mctx);
  59
  60         return (event);
  61 }
  62
  63 isc_event_t *
  64 isc_event_constallocate(isc_mem_t *mctx, void *sender, isc_eventtype_t type,
  65                         isc_taskaction_t action, const void *arg, size_t size)
  66 {
  67         isc_event_t *event;
  68         void *deconst_arg;
  69
  70         REQUIRE(size >= sizeof(struct isc_event));
  71         REQUIRE(action != NULL);
  72
  73         event = isc_mem_get(mctx, size);
  74         if (event == NULL)
  75                 return (NULL);
  76
  77         /*
  78          * Removing the const attribute from "arg" is the best of two
  79          * evils here.  If the event->ev_arg member is made const, then
  80          * it affects a great many users of the task/event subsystem
  81          * which are not passing in an "arg" which starts its life as
  82          * const.  Changing isc_event_allocate() and isc_task_onshutdown()
  83          * to not have "arg" prototyped as const (which is quite legitimate,
  84          * because neither of those functions modify arg) can cause
  85          * compiler whining anytime someone does want to use a const
  86          * arg that they themselves never modify, such as with
  87          * gcc -Wwrite-strings and using a string "arg".
  88          */
  89         DE_CONST(arg, deconst_arg);
  90
  91         ISC_EVENT_INIT(event, size, 0, NULL, type, action, deconst_arg,
  92                        sender, destroy, mctx);
  93
  94         return (event);
  95 }
  96
  97 void
  98 isc_event_free(isc_event_t **eventp) {
  99         isc_event_t *event;
 100
 101         REQUIRE(eventp != NULL);
 102         event = *eventp;
 103         REQUIRE(event != NULL);
 104
 105         if (event->ev_destroy != NULL)
 106                 (event->ev_destroy)(event);
 107
 108         *eventp = NULL;
 109 }