1258945Sroberto/* 2258945Sroberto * Copyright (C) 2004, 2007 Internet Systems Consortium, Inc. ("ISC") 3258945Sroberto * Copyright (C) 1999-2001 Internet Software Consortium. 4258945Sroberto * 5258945Sroberto * Permission to use, copy, modify, and/or distribute this software for any 6258945Sroberto * purpose with or without fee is hereby granted, provided that the above 7258945Sroberto * copyright notice and this permission notice appear in all copies. 8258945Sroberto * 9258945Sroberto * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH 10258945Sroberto * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 11258945Sroberto * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, 12258945Sroberto * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 13258945Sroberto * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE 14258945Sroberto * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 15258945Sroberto * PERFORMANCE OF THIS SOFTWARE. 16258945Sroberto */ 17258945Sroberto 18258945Sroberto/* $Id: once.c,v 1.12 2007/06/18 23:47:49 tbox Exp $ */ 19258945Sroberto 20258945Sroberto/* Principal Authors: DCL */ 21258945Sroberto 22258945Sroberto#include <config.h> 23258945Sroberto 24258945Sroberto#include <windows.h> 25258945Sroberto 26258945Sroberto#include <isc/once.h> 27258945Sroberto#include <isc/assertions.h> 28258945Sroberto#include <isc/util.h> 29258945Sroberto 30258945Srobertoisc_result_t 31258945Srobertoisc_once_do(isc_once_t *controller, void(*function)(void)) { 32258945Sroberto REQUIRE(controller != NULL && function != NULL); 33258945Sroberto 34258945Sroberto if (controller->status == ISC_ONCE_INIT_NEEDED) { 35258945Sroberto 36258945Sroberto if (InterlockedDecrement(&controller->counter) == 0) { 37258945Sroberto if (controller->status == ISC_ONCE_INIT_NEEDED) { 38258945Sroberto function(); 39258945Sroberto controller->status = ISC_ONCE_INIT_DONE; 40258945Sroberto } 41258945Sroberto } else { 42258945Sroberto while (controller->status == ISC_ONCE_INIT_NEEDED) { 43258945Sroberto /* 44258945Sroberto * Sleep(0) indicates that this thread 45258945Sroberto * should be suspended to allow other 46258945Sroberto * waiting threads to execute. 47258945Sroberto */ 48258945Sroberto Sleep(0); 49258945Sroberto } 50258945Sroberto } 51258945Sroberto } 52258945Sroberto 53258945Sroberto return (ISC_R_SUCCESS); 54258945Sroberto} 55