1 /* 2 * Copyright (C) Internet Systems Consortium, Inc. ("ISC") 3 * 4 * SPDX-License-Identifier: MPL-2.0 5 * 6 * This Source Code Form is subject to the terms of the Mozilla Public 7 * License, v. 2.0. If a copy of the MPL was not distributed with this 8 * file, you can obtain one at https://mozilla.org/MPL/2.0/. 9 * 10 * See the COPYRIGHT file distributed with this work for additional 11 * information regarding copyright ownership. 12 */ 13 14 #include <windows.h> 15 16 #include <isc/assertions.h> 17 #include <isc/once.h> 18 #include <isc/util.h> 19 20 isc_result_t isc_once_do(isc_once_t * controller,void (* function)(void))21isc_once_do(isc_once_t *controller, void (*function)(void)) { 22 REQUIRE(controller != NULL && function != NULL); 23 24 if (controller->status == ISC_ONCE_INIT_NEEDED) { 25 if (InterlockedDecrement(&controller->counter) == 0) { 26 if (controller->status == ISC_ONCE_INIT_NEEDED) { 27 function(); 28 controller->status = ISC_ONCE_INIT_DONE; 29 } 30 } else { 31 while (controller->status == ISC_ONCE_INIT_NEEDED) { 32 /* 33 * Sleep(0) indicates that this thread 34 * should be suspended to allow other 35 * waiting threads to execute. 36 */ 37 Sleep(0); 38 } 39 } 40 } 41 42 return (ISC_R_SUCCESS); 43 } 44