1 /************************************************************** 2 * 3 * Licensed to the Apache Software Foundation (ASF) under one 4 * or more contributor license agreements. See the NOTICE file 5 * distributed with this work for additional information 6 * regarding copyright ownership. The ASF licenses this file 7 * to you under the Apache License, Version 2.0 (the 8 * "License"); you may not use this file except in compliance 9 * with the License. You may obtain a copy of the License at 10 * 11 * http://www.apache.org/licenses/LICENSE-2.0 12 * 13 * Unless required by applicable law or agreed to in writing, 14 * software distributed under the License is distributed on an 15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 16 * KIND, either express or implied. See the License for the 17 * specific language governing permissions and limitations 18 * under the License. 19 * 20 *************************************************************/ 21 22 23 24 #ifndef INCLUDED_SAL_INTERNAL_ONCE_H 25 #define INCLUDED_SAL_INTERNAL_ONCE_H 26 27 /** sal_once_type 28 * (platform dependent) 29 */ 30 31 #if defined(SAL_UNX) || defined(SAL_OS2) 32 33 #include <pthread.h> 34 35 typedef pthread_once_t sal_once_type; 36 37 #define SAL_ONCE_INIT PTHREAD_ONCE_INIT 38 #define SAL_ONCE(once, init) pthread_once((once), (init)) 39 40 #elif defined(SAL_W32) 41 42 #define WIN32_LEAN_AND_MEAN 43 #pragma warning(push,1) /* disable warnings within system headers */ 44 #include <windows.h> 45 #pragma warning(pop) 46 47 typedef struct sal_once_st sal_once_type; 48 struct sal_once_st 49 { 50 LONG volatile m_done; 51 LONG volatile m_lock; 52 }; 53 54 #define SAL_ONCE_INIT { 0, 0 } 55 #define SAL_ONCE(once, init) \ 56 { \ 57 sal_once_type * control = (once); \ 58 if (!(control->m_done)) \ 59 { \ 60 while (InterlockedExchange(&(control->m_lock), 1) == 1) Sleep(0); \ 61 if (!(control->m_done)) \ 62 { \ 63 void (*init_routine)(void) = (init); \ 64 (*init_routine)(); \ 65 control->m_done = 1; \ 66 } \ 67 InterlockedExchange(&(control->m_lock), 0); \ 68 } \ 69 } 70 71 #else 72 #error Unknown platform 73 #endif /* SAL_UNX | SAL_W32 */ 74 75 #endif /* INCLUDED_SAL_INTERNAL_ONCE_H */ 76