windows-xp/Source/XPSP1/NT/base/fs/sis/groveler/mutex.cpp

/*++

Copyright (c) 1998  Microsoft Corporation

Module Name:

    mutex.cpp

Abstract:

	SIS Groveler named mutex class

Authors:

	John Douceur, 1998

Environment:

	User Mode


Revision History:


--*/

#include "all.hxx"

NamedMutex::NamedMutex(
	const _TCHAR *name,
	SECURITY_ATTRIBUTES *security_attributes)
{
	ASSERT(this != 0);
	mutex_handle = CreateMutex(security_attributes, FALSE, name);
	if (mutex_handle == 0)
	{
		DWORD err = GetLastError();
		PRINT_DEBUG_MSG((_T("GROVELER: CreateMutex() failed with error %d\n"), err));
	}
}

NamedMutex::~NamedMutex()
{
	ASSERT(this != 0);
	if (mutex_handle != 0)
	{
		int ok = CloseHandle(mutex_handle);
		if (!ok)
		{
			DWORD err = GetLastError();
			PRINT_DEBUG_MSG((_T("GROVELER: CloseHandle() failed with error %d\n"), err));
		}
		mutex_handle = 0;
	}
}

bool
NamedMutex::release()
{
	ASSERT(this != 0);
	if (mutex_handle == 0)
	{
		return false;
	}
	BOOL ok = ReleaseMutex(mutex_handle);
	if (!ok)
	{
		DWORD err = GetLastError();
		PRINT_DEBUG_MSG((_T("GROVELER: ReleaseMutex() failed with error %d\n"), err));
	}
	return (ok != 0);
}

bool
NamedMutex::acquire(
	unsigned int timeout)
{
	ASSERT(this != 0);
	if (mutex_handle == 0)
	{
		return false;
	}
	ASSERT(signed(timeout) >= 0);
	DWORD result = WaitForSingleObject(mutex_handle, timeout);
	if (result != WAIT_TIMEOUT && result != WAIT_OBJECT_0)
	{
		PRINT_DEBUG_MSG((_T("GROVELER: WaitForSingleObject() returned error %d\n"),
			result));
	}
	return (result == WAIT_OBJECT_0);
}