/** @file * IPRT - Critical Sections. */ /* * Copyright (C) 2006-2007 Sun Microsystems, Inc. * * This file is part of VirtualBox Open Source Edition (OSE), as * available from http://www.virtualbox.org. This file is free software; * you can redistribute it and/or modify it under the terms of the GNU * General Public License (GPL) as published by the Free Software * Foundation, in version 2 as it comes in the "COPYING" file of the * VirtualBox OSE distribution. VirtualBox OSE is distributed in the * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind. * * The contents of this file may alternatively be used under the terms * of the Common Development and Distribution License Version 1.0 * (CDDL) only, as it comes in the "COPYING.CDDL" file of the * VirtualBox OSE distribution, in which case the provisions of the * CDDL are applicable instead of those of the GPL. * * You may elect to license modified versions of this file under the * terms and conditions of either the GPL or the CDDL or both. * * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa * Clara, CA 95054 USA or visit http://www.sun.com if you need * additional information or have any questions. */ #ifndef ___iprt_critsect_h #define ___iprt_critsect_h #include #include #ifdef IN_RING3 #include #endif RT_C_DECLS_BEGIN /** @defgroup grp_rt_critsect RTCritSect - Critical Sections * @ingroup grp_rt * @{ */ /** * Critical section. */ typedef struct RTCRITSECT { /** Magic used to validate the section state. * RTCRITSECT_MAGIC is the value of an initialized & operational section. */ volatile uint32_t u32Magic; /** Number of lockers. * -1 if the section is free. */ volatile int32_t cLockers; /** The owner thread. */ volatile RTNATIVETHREAD NativeThreadOwner; /** Number of nested enter operations performed. * Greater or equal to 1 if owned, 0 when free. */ volatile int32_t cNestings; /** Section flags - the RTCRITSECT_FLAGS_* \#defines. */ uint32_t fFlags; /** The semaphore to wait for. */ RTSEMEVENT EventSem; /** Data only used in strict mode for detecting and debugging deadlocks. */ struct RTCRITSECTSTRICT { /** Strict: The current owner thread. */ RTTHREAD volatile ThreadOwner; /** Strict: Where the section was entered. */ R3PTRTYPE(const char * volatile) pszEnterFile; /** Strict: Where the section was entered. */ uint32_t volatile u32EnterLine; #if HC_ARCH_BITS == 64 || GC_ARCH_BITS == 64 /** Padding for correct alignment. */ uint32_t u32Padding; #endif /** Strict: Where the section was entered. */ RTUINTPTR volatile uEnterId; } Strict; } RTCRITSECT; /** Pointer to a critical section. */ typedef RTCRITSECT *PRTCRITSECT; /** Pointer to a const critical section. */ typedef const RTCRITSECT *PCRTCRITSECT; /** RTCRITSECT::u32Magic value. */ #define RTCRITSECT_MAGIC 0x778899aa /** If set, nesting(/recursion) is not allowed. */ #define RTCRITSECT_FLAGS_NO_NESTING 1 #ifdef IN_RING3 /** * Initialize a critical section. */ RTDECL(int) RTCritSectInit(PRTCRITSECT pCritSect); /** * Initialize a critical section. * * @returns iprt status code. * @param pCritSect Pointer to the critical section structure. * @param fFlags Flags, any combination of the RTCRITSECT_FLAGS \#defines. */ RTDECL(int) RTCritSectInitEx(PRTCRITSECT pCritSect, uint32_t fFlags); /** * Enter a critical section. * * @returns VINF_SUCCESS on success. * @returns VERR_SEM_NESTED if nested enter on a no nesting section. (Asserted.) * @returns VERR_SEM_DESTROYED if RTCritSectDelete was called while waiting. * @param pCritSect The critical section. */ RTDECL(int) RTCritSectEnter(PRTCRITSECT pCritSect); /** * Enter a critical section. * * @returns VINF_SUCCESS on success. * @returns VERR_SEM_NESTED if nested enter on a no nesting section. (Asserted.) * @returns VERR_SEM_DESTROYED if RTCritSectDelete was called while waiting. * @param pCritSect The critical section. * @param pszFile Where we're entering the section. * @param uLine Where we're entering the section. * @param uId Where we're entering the section. */ RTDECL(int) RTCritSectEnterDebug(PRTCRITSECT pCritSect, const char *pszFile, unsigned uLine, RTUINTPTR uId); /* in debug mode we'll redefine the enter call. */ #ifdef RT_STRICT # define RTCritSectEnter(pCritSect) RTCritSectEnterDebug(pCritSect, __FILE__, __LINE__, 0) #endif /** * Try enter a critical section. * * @returns VINF_SUCCESS on success. * @returns VERR_SEM_BUSY if the critsect was owned. * @returns VERR_SEM_NESTED if nested enter on a no nesting section. (Asserted.) * @returns VERR_SEM_DESTROYED if RTCritSectDelete was called while waiting. * @param pCritSect The critical section. */ RTDECL(int) RTCritSectTryEnter(PRTCRITSECT pCritSect); /** * Try enter a critical section. * * @returns VINF_SUCCESS on success. * @returns VERR_SEM_BUSY if the critsect was owned. * @returns VERR_SEM_NESTED if nested enter on a no nesting section. (Asserted.) * @returns VERR_SEM_DESTROYED if RTCritSectDelete was called while waiting. * @param pCritSect The critical section. * @param pszFile Where we're entering the section. * @param uLine Where we're entering the section. * @param uId Where we're entering the section. */ RTDECL(int) RTCritSectTryEnterDebug(PRTCRITSECT pCritSect, const char *pszFile, unsigned uLine, RTUINTPTR uId); /* in debug mode we'll redefine the try-enter call. */ #ifdef RT_STRICT # define RTCritSectTryEnter(pCritSect) RTCritSectTryEnterDebug(pCritSect, __FILE__, __LINE__, 0) #endif /** * Enter multiple critical sections. * * This function will enter ALL the specified critical sections before returning. * * @returns VINF_SUCCESS on success. * @returns VERR_SEM_NESTED if nested enter on a no nesting section. (Asserted.) * @returns VERR_SEM_DESTROYED if RTCritSectDelete was called while waiting. * @param cCritSects Number of critical sections in the array. * @param papCritSects Array of critical section pointers. * * @remark Please note that this function will not necessarily come out favourable in a * fight with other threads which are using the normal RTCritSectEnter() function. * Therefore, avoid having to enter multiple critical sections! */ RTDECL(int) RTCritSectEnterMultiple(unsigned cCritSects, PRTCRITSECT *papCritSects); /** * Enter multiple critical sections. * * This function will enter ALL the specified critical sections before returning. * * @returns VINF_SUCCESS on success. * @returns VERR_SEM_NESTED if nested enter on a no nesting section. (Asserted.) * @returns VERR_SEM_DESTROYED if RTCritSectDelete was called while waiting. * * @param cCritSects Number of critical sections in the array. * @param papCritSects Array of critical section pointers. * @param pszFile Where we're entering the section. * @param uLine Where we're entering the section. * @param uId Where we're entering the section. * * @remark See RTCritSectEnterMultiple(). */ RTDECL(int) RTCritSectEnterMultipleDebug(unsigned cCritSects, PRTCRITSECT *papCritSects, const char *pszFile, unsigned uLine, RTUINTPTR uId); /* in debug mode we'll redefine the enter-multiple call. */ #ifdef RT_STRICT # define RTCritSectEnterMultiple(cCritSects, pCritSect) RTCritSectEnterMultipleDebug((cCritSects), (pCritSect), __FILE__, __LINE__, 0) #endif /** * Leave a critical section. * * @returns VINF_SUCCESS. * @param pCritSect The critical section. */ RTDECL(int) RTCritSectLeave(PRTCRITSECT pCritSect); /** * Leave multiple critical sections. * * @returns VINF_SUCCESS. * @param cCritSects Number of critical sections in the array. * @param papCritSects Array of critical section pointers. */ RTDECL(int) RTCritSectLeaveMultiple(unsigned cCritSects, PRTCRITSECT *papCritSects); /** * Deletes a critical section. * * @returns VINF_SUCCESS. * @param pCritSect The critical section. */ RTDECL(int) RTCritSectDelete(PRTCRITSECT pCritSect); /** * Checks the caller is the owner of the critical section. * * @returns true if owner. * @returns false if not owner. * @param pCritSect The critical section. */ DECLINLINE(bool) RTCritSectIsOwner(PCRTCRITSECT pCritSect) { return pCritSect->NativeThreadOwner == RTThreadNativeSelf(); } #endif /* IN_RING3 */ /** * Checks the section is owned by anyone. * * @returns true if owned. * @returns false if not owned. * @param pCritSect The critical section. */ DECLINLINE(bool) RTCritSectIsOwned(PCRTCRITSECT pCritSect) { return pCritSect->NativeThreadOwner != NIL_RTNATIVETHREAD; } /** * Gets the thread id of the critical section owner. * * @returns Thread id of the owner thread if owned. * @returns NIL_RTNATIVETHREAD is not owned. * @param pCritSect The critical section. */ DECLINLINE(RTNATIVETHREAD) RTCritSectGetOwner(PCRTCRITSECT pCritSect) { return pCritSect->NativeThreadOwner; } /** * Checks if a critical section is initialized or not. * * @returns true if initialized. * @returns false if not initialized. * @param pCritSect The critical section. */ DECLINLINE(bool) RTCritSectIsInitialized(PCRTCRITSECT pCritSect) { return pCritSect->u32Magic == RTCRITSECT_MAGIC; } /** * Gets the recursion depth. * * @returns The recursion depth. * @param pCritSect The Critical section */ DECLINLINE(uint32_t) RTCritSectGetRecursion(PCRTCRITSECT pCritSect) { return pCritSect->cNestings; } /** * Gets the waiter count * * @returns The waiter count * @param pCritSect The Critical section */ DECLINLINE(int32_t) RTCritSectGetWaiters(PCRTCRITSECT pCritSect) { return pCritSect->cLockers; } /** @} */ RT_C_DECLS_END #endif