office-gobmx/sal/osl/w32/mutex.c

206 lines
6 KiB
C

/*************************************************************************
*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* Copyright 2000, 2010 Oracle and/or its affiliates.
*
* OpenOffice.org - a multi-platform office productivity suite
*
* This file is part of OpenOffice.org.
*
* OpenOffice.org is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License version 3
* only, as published by the Free Software Foundation.
*
* OpenOffice.org is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License version 3 for more details
* (a copy is included in the LICENSE file that accompanied this code).
*
* You should have received a copy of the GNU Lesser General Public License
* version 3 along with OpenOffice.org. If not, see
* <http://www.openoffice.org/license.html>
* for a copy of the LGPLv3 License.
*
************************************************************************/
#include "system.h"
#include <osl/mutex.h>
#include <osl/diagnose.h>
/*
Implementation notes:
The void* hidden by oslMutex points to a WIN32
CRITICAL_SECTION structure.
*/
typedef struct _oslMutexImpl {
CRITICAL_SECTION m_Mutex;
int m_Locks;
DWORD m_Owner;
DWORD m_Requests;
} oslMutexImpl;
static BOOL (WINAPI *lpfTryEnterCriticalSection)(LPCRITICAL_SECTION)
= (BOOL (WINAPI *)(LPCRITICAL_SECTION))0xFFFFFFFF;
static CRITICAL_SECTION MutexLock;
/*****************************************************************************/
/* osl_createMutex */
/*****************************************************************************/
oslMutex SAL_CALL osl_createMutex(void)
{
oslMutexImpl *pMutexImpl;
/* Window 95 does not support "TryEnterCriticalSection" */
if (lpfTryEnterCriticalSection ==
(BOOL (WINAPI *)(LPCRITICAL_SECTION))0xFFFFFFFF)
{
OSVERSIONINFO VersionInformation =
{
sizeof(OSVERSIONINFO),
0,
0,
0,
0,
"",
};
/* ts: Window 98 does not support "TryEnterCriticalSection" but export the symbol !!!
calls to that symbol always returns FALSE */
if (
GetVersionEx(&VersionInformation) &&
(VersionInformation.dwPlatformId == VER_PLATFORM_WIN32_NT)
)
{
lpfTryEnterCriticalSection = (BOOL (WINAPI *)(LPCRITICAL_SECTION))
GetProcAddress(GetModuleHandle("KERNEL32"),
"TryEnterCriticalSection");
}
else
{
lpfTryEnterCriticalSection = (BOOL (WINAPI *)(LPCRITICAL_SECTION))NULL;
}
InitializeCriticalSection(&MutexLock);
}
pMutexImpl= calloc(sizeof(oslMutexImpl), 1);
OSL_ASSERT(pMutexImpl); /* alloc successful? */
InitializeCriticalSection(&pMutexImpl->m_Mutex);
return (oslMutex)pMutexImpl;
}
/*****************************************************************************/
/* osl_destroyMutex */
/*****************************************************************************/
void SAL_CALL osl_destroyMutex(oslMutex Mutex)
{
oslMutexImpl *pMutexImpl = (oslMutexImpl *)Mutex;
if (pMutexImpl)
{
DeleteCriticalSection(&pMutexImpl->m_Mutex);
free(pMutexImpl);
}
}
/*****************************************************************************/
/* osl_acquireMutex */
/*****************************************************************************/
sal_Bool SAL_CALL osl_acquireMutex(oslMutex Mutex)
{
oslMutexImpl *pMutexImpl = (oslMutexImpl *)Mutex;
OSL_ASSERT(Mutex);
if (lpfTryEnterCriticalSection == NULL)
{
EnterCriticalSection(&MutexLock);
pMutexImpl->m_Requests++;
LeaveCriticalSection(&MutexLock);
EnterCriticalSection(&pMutexImpl->m_Mutex);
EnterCriticalSection(&MutexLock);
pMutexImpl->m_Requests--;
if (pMutexImpl->m_Locks++ == 0)
pMutexImpl->m_Owner = GetCurrentThreadId();
LeaveCriticalSection(&MutexLock);
}
else
EnterCriticalSection(&pMutexImpl->m_Mutex);
return sal_True;
}
/*****************************************************************************/
/* osl_tryToAcquireMutex */
/*****************************************************************************/
sal_Bool SAL_CALL osl_tryToAcquireMutex(oslMutex Mutex)
{
sal_Bool ret = sal_False;
oslMutexImpl *pMutexImpl = (oslMutexImpl *)Mutex;
OSL_ASSERT(Mutex);
if (lpfTryEnterCriticalSection != NULL)
return (sal_Bool)(lpfTryEnterCriticalSection(&pMutexImpl->m_Mutex) != FALSE);
else
{
EnterCriticalSection(&MutexLock);
if ( ((pMutexImpl->m_Requests == 0) && (pMutexImpl->m_Locks == 0)) ||
(pMutexImpl->m_Owner == GetCurrentThreadId()) )
ret = osl_acquireMutex(Mutex);
LeaveCriticalSection(&MutexLock);
}
return ret;
}
/*****************************************************************************/
/* osl_releaseMutex */
/*****************************************************************************/
sal_Bool SAL_CALL osl_releaseMutex(oslMutex Mutex)
{
oslMutexImpl *pMutexImpl = (oslMutexImpl *)Mutex;
OSL_ASSERT(Mutex);
if (lpfTryEnterCriticalSection == NULL)
{
EnterCriticalSection(&MutexLock);
if (--(pMutexImpl->m_Locks) == 0)
pMutexImpl->m_Owner = 0;
LeaveCriticalSection(&MutexLock);
}
LeaveCriticalSection(&pMutexImpl->m_Mutex);
return sal_True;
}
/*****************************************************************************/
/* osl_getGlobalMutex */
/*****************************************************************************/
/* initialized in dllentry.c */
oslMutex g_Mutex;
oslMutex * SAL_CALL osl_getGlobalMutex(void)
{
return &g_Mutex;
}