152 lines
6.1 KiB
C
152 lines
6.1 KiB
C
/************************************************************************************//**
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* \file port/windows/critutil.c
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* \brief Critical section utility source file.
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* \ingroup Utility
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* \internal
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*----------------------------------------------------------------------------------------
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* C O P Y R I G H T
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*----------------------------------------------------------------------------------------
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* Copyright (c) 2017 by Feaser http://www.feaser.com All rights reserved
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*
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*----------------------------------------------------------------------------------------
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* L I C E N S E
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*----------------------------------------------------------------------------------------
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* This file is part of OpenBLT. OpenBLT is free software: you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as published by the Free
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* Software Foundation, either version 3 of the License, or (at your option) any later
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* version.
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*
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* OpenBLT is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
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* without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
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* PURPOSE. See the GNU General Public License for more details.
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*
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* You have received a copy of the GNU General Public License along with OpenBLT. It
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* should be located in ".\Doc\license.html". If not, contact Feaser to obtain a copy.
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*
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* \endinternal
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****************************************************************************************/
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/****************************************************************************************
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* Include files
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****************************************************************************************/
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#include <assert.h> /* for assertions */
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#include <stdint.h> /* for standard integer types */
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#include <stdbool.h> /* for boolean type */
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#include <windows.h> /* for windows library */
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#include "util.h" /* Utility module */
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/****************************************************************************************
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* Local data declarations
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****************************************************************************************/
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/** \brief Flag to determine if the critical section object was already initialized. */
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static volatile bool criticalSectionInitialized = false;
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/** \brief Crital section nesting counter. ***/
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static volatile uint32_t criticalSectionNesting;
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/** \brief Critical section object. */
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static volatile CRITICAL_SECTION criticalSection;
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/************************************************************************************//**
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** \brief Initializes the critical section module. Should be called before the
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** Enter/Exit functions are used. It is okay to call this initialization
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** multiple times from different modules.
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**
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****************************************************************************************/
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void UtilCriticalSectionInit(void)
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{
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/* Only initialize if not yet done so previously. */
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if (!criticalSectionInitialized)
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{
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/* Initialize the critical section object. */
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InitializeCriticalSection(&criticalSection);
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/* Reset nesting counter. */
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criticalSectionNesting = 0;
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/* Set initialized flag. */
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criticalSectionInitialized = true;
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}
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} /*** end of UtilCriticalSectionInit ***/
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/************************************************************************************//**
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** \brief Terminates the critical section module. Should be called once critical
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** sections are no longer needed. Typically called from another module's
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** termination function that also initialized it. It is okay to call this
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** termination multiple times from different modules.
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**
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****************************************************************************************/
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void UtilCriticalSectionTerminate(void)
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{
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/* Only terminate if it was initialized. */
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if (criticalSectionInitialized)
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{
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/* Reset the initialized flag. */
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criticalSectionInitialized = false;
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/* Reset nesting counter. */
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criticalSectionNesting = 0;
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/* Delete the critical section object. */
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DeleteCriticalSection(&criticalSection);
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}
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} /*** end of UtilCriticalSectionTerminate ***/
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/************************************************************************************//**
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** \brief Enters a critical section. The functions UtilCriticalSectionEnter and
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** UtilCriticalSectionExit should always be used in a pair.
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**
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****************************************************************************************/
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void UtilCriticalSectionEnter(void)
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{
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/* Check initialization. */
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assert(criticalSectionInitialized);
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/* Only continue if actually initialized. */
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if (criticalSectionInitialized)
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{
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/* Enter the critical section if not already entered. */
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if (criticalSectionNesting == 0)
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{
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EnterCriticalSection(&criticalSection);
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}
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/* Increment nesting counter. */
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criticalSectionNesting++;
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}
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} /*** end of UtilCriticalSectionEnter ***/
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/************************************************************************************//**
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** \brief Leaves a critical section. The functions UtilCriticalSectionEnter and
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** UtilCriticalSectionExit should always be used in a pair.
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**
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****************************************************************************************/
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void UtilCriticalSectionExit(void)
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{
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/* Check initialization. */
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assert(criticalSectionInitialized);
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/* Only continue if actually initialized. */
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if (criticalSectionInitialized)
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{
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/* Sanity check. */
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assert(criticalSectionNesting > 0);
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/* Decrement nesting counter if it is valid. */
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if (criticalSectionNesting > 0)
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{
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criticalSectionNesting--;
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/* Leave the critical section. */
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if (criticalSectionNesting == 0)
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{
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LeaveCriticalSection(&criticalSection);
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}
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}
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}
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} /*** end of UtilCriticalSectionExit ***/
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/*********************************** end of critutil.c *********************************/
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