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Diffstat (limited to 'src/VBox/Runtime/common/misc/term.cpp')
| -rw-r--r-- | src/VBox/Runtime/common/misc/term.cpp | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/misc/term.cpp b/src/VBox/Runtime/common/misc/term.cpp new file mode 100644 index 00000000..31188728 --- /dev/null +++ b/src/VBox/Runtime/common/misc/term.cpp @@ -0,0 +1,242 @@ +/* $Id: term.cpp $ */ +/** @file + * IPRT - Common Termination Code. + */ + +/* + * Copyright (C) 2009-2019 Oracle Corporation + * + * 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. + */ + + +/********************************************************************************************************************************* +* Header Files * +*********************************************************************************************************************************/ +#include <iprt/initterm.h> +#include "internal/iprt.h" + +#include <iprt/asm.h> +#include <iprt/assert.h> +#include <iprt/errcore.h> +#include <iprt/mem.h> +#include <iprt/once.h> +#include <iprt/semaphore.h> +#include <iprt/thread.h> + + +/********************************************************************************************************************************* +* Structures and Typedefs * +*********************************************************************************************************************************/ +/** Pointer to a termination callback record. */ +typedef struct RTTERMCALLBACKREC *PRTTERMCALLBACKREC; +/** + * Termination callback record. + */ +typedef struct RTTERMCALLBACKREC +{ + /** Pointer to the next record. */ + PRTTERMCALLBACKREC pNext; + /** Pointer to the callback. */ + PFNRTTERMCALLBACK pfnCallback; + /** The user argument. */ + void *pvUser; +} RTTERMCALLBACKREC; + + +/********************************************************************************************************************************* +* Global Variables * +*********************************************************************************************************************************/ +/** Execute once construct protecting lazy callback initialization. */ +static RTONCE g_InitTermCallbacksOnce = RTONCE_INITIALIZER; +/** Mutex protecting the callback globals. */ +static RTSEMFASTMUTEX g_hFastMutex = NIL_RTSEMFASTMUTEX; +/** Number of registered callbacks. */ +static uint32_t g_cCallbacks = 0; +/** The callback head. */ +static PRTTERMCALLBACKREC g_pCallbackHead = NULL; + + + +/** + * Initializes the globals. + * + * @returns IPRT status code + * @param pvUser Ignored. + */ +static DECLCALLBACK(int32_t) rtTermInitOnce(void *pvUser) +{ + RTSEMFASTMUTEX hFastMutex; + int rc; + + Assert(!g_cCallbacks); + Assert(!g_pCallbackHead); + Assert(g_hFastMutex == NIL_RTSEMFASTMUTEX); + + rc = RTSemFastMutexCreate(&hFastMutex); + if (RT_SUCCESS(rc)) + g_hFastMutex = hFastMutex; + + NOREF(pvUser); + + return rc; +} + + + +RTDECL(int) RTTermRegisterCallback(PFNRTTERMCALLBACK pfnCallback, void *pvUser) +{ + int rc; + PRTTERMCALLBACKREC pNew; + + /* + * Validation and lazy init. + */ + AssertPtrReturn(pfnCallback, VERR_INVALID_POINTER); + + rc = RTOnce(&g_InitTermCallbacksOnce, rtTermInitOnce, NULL); + if (RT_FAILURE(rc)) + return rc; + + /* + * Allocate and initialize a new callback record. + */ + pNew = (PRTTERMCALLBACKREC)RTMemAlloc(sizeof(*pNew)); + if (!pNew) + return VERR_NO_MEMORY; + pNew->pfnCallback = pfnCallback; + pNew->pvUser = pvUser; + + /* + * Insert into the list. + */ + rc = RTSemFastMutexRequest(g_hFastMutex); + if (RT_SUCCESS(rc)) + { + g_cCallbacks++; + pNew->pNext = g_pCallbackHead; + g_pCallbackHead = pNew; + + RTSemFastMutexRelease(g_hFastMutex); + } + else + RTMemFree(pNew); + + return rc; +} +RT_EXPORT_SYMBOL(RTTermRegisterCallback); + + +RTDECL(int) RTTermDeregisterCallback(PFNRTTERMCALLBACK pfnCallback, void *pvUser) +{ + /* + * g_hFastMutex will be NIL if we're not initialized. + */ + int rc; + RTSEMFASTMUTEX hFastMutex = g_hFastMutex; + if (hFastMutex == NIL_RTSEMFASTMUTEX) + return VERR_NOT_FOUND; + + rc = RTSemFastMutexRequest(hFastMutex); + if (RT_SUCCESS(rc)) + { + + /* + * Search for the specified pfnCallback/pvUser pair. + */ + PRTTERMCALLBACKREC pPrev = NULL; + PRTTERMCALLBACKREC pCur = g_pCallbackHead; + while (pCur) + { + if ( pCur->pfnCallback == pfnCallback + && pCur->pvUser == pvUser) + { + if (pPrev) + pPrev->pNext = pCur->pNext; + else + g_pCallbackHead = pCur->pNext; + g_cCallbacks--; + RTSemFastMutexRelease(hFastMutex); + + pCur->pfnCallback = NULL; + RTMemFree(pCur); + return VINF_SUCCESS; + } + + /* next */ + pPrev = pCur; + pCur = pCur->pNext; + } + + RTSemFastMutexRelease(hFastMutex); + rc = VERR_NOT_FOUND; + } + + return rc; +} +RT_EXPORT_SYMBOL(RTTermDeregisterCallback); + + +RTDECL(void) RTTermRunCallbacks(RTTERMREASON enmReason, int32_t iStatus) +{ + RTSEMFASTMUTEX hFastMutex; + Assert( enmReason == RTTERMREASON_EXIT + || enmReason == RTTERMREASON_ABEND + || enmReason == RTTERMREASON_SIGNAL + || enmReason == RTTERMREASON_UNLOAD); + + /* + * Run the callback list. This is a bit paranoid in order to guard against + * recursive calls to RTTermRunCallbacks. + */ + while (g_hFastMutex != NIL_RTSEMFASTMUTEX) + { + PRTTERMCALLBACKREC pCur; + RTTERMCALLBACKREC CurCopy; + int rc; + + /* Unlink the head of the chain. */ + rc = RTSemFastMutexRequest(g_hFastMutex); + AssertRCReturnVoid(rc); + pCur = g_pCallbackHead; + if (pCur) + { + g_pCallbackHead = pCur->pNext; + g_cCallbacks--; + } + RTSemFastMutexRelease(g_hFastMutex); + if (!pCur) + break; + + /* Copy and free it. */ + CurCopy = *pCur; + RTMemFree(pCur); + + /* Make the call. */ + CurCopy.pfnCallback(enmReason, iStatus, CurCopy.pvUser); + } + + /* + * Free the lock. + */ + ASMAtomicXchgHandle(&g_hFastMutex, NIL_RTSEMFASTMUTEX, &hFastMutex); + RTSemFastMutexDestroy(hFastMutex); + RTOnceReset(&g_InitTermCallbacksOnce); /* for the testcase */ +} +RT_EXPORT_SYMBOL(RTTermRunCallbacks); + |