411 lines
11 KiB
C++
411 lines
11 KiB
C++
|
///+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// File: Sem.Hxx
|
||
|
|
//
|
||
|
|
// Contents: Semaphore classes
|
||
|
|
//
|
||
|
|
// Classes: CMutexSem - Mutex semaphore class
|
||
|
|
// CShareSem - Multiple Reader, Single Writer class
|
||
|
|
// CEventSem - Event semaphore
|
||
|
|
//
|
||
|
|
// History: 21-Jun-91 AlexT Created.
|
||
|
|
//
|
||
|
|
// Notes: No 32-bit implementation exists yet for these classes, it
|
||
|
|
// will be provided when we have a 32-bit development
|
||
|
|
// environment. In the meantime, the 16-bit implementations
|
||
|
|
// provided here can be used to ensure your code not blocking
|
||
|
|
// while you hold a semaphore.
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
#ifndef __SEM32_HXX__
|
||
|
|
#define __SEM32_HXX__
|
||
|
|
|
||
|
|
#include <windows.h>
|
||
|
|
#include <except.hxx>
|
||
|
|
|
||
|
|
// This is temporary. To be moved to the appropriate error file
|
||
|
|
|
||
|
|
enum SEMRESULT
|
||
|
|
{
|
||
|
|
SEMSUCCESS = 0,
|
||
|
|
SEMTIMEOUT,
|
||
|
|
SEMNOBLOCK,
|
||
|
|
SEMERROR
|
||
|
|
};
|
||
|
|
|
||
|
|
enum SEMSTATE
|
||
|
|
{
|
||
|
|
SEMSHARED,
|
||
|
|
SEMSHAREDOWNED
|
||
|
|
};
|
||
|
|
|
||
|
|
// infinite timeout when requesting a semaphore
|
||
|
|
|
||
|
|
#if !defined INFINITE
|
||
|
|
#define INFINITE 0xFFFFFFFF
|
||
|
|
#endif
|
||
|
|
|
||
|
|
//+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Class: CMutexSem (mxs)
|
||
|
|
//
|
||
|
|
// Purpose: Mutex Semaphore services
|
||
|
|
//
|
||
|
|
// Interface: Init - initializer (two-step)
|
||
|
|
// Request - acquire semaphore
|
||
|
|
// Release - release semaphore
|
||
|
|
//
|
||
|
|
// History: 14-Jun-91 AlexT Created.
|
||
|
|
// 30-oct-91 SethuR 32 bit implementation
|
||
|
|
//
|
||
|
|
// Notes: This class wraps a mutex semaphore. Mutex semaphores protect
|
||
|
|
// access to resources by only allowing one client through at a
|
||
|
|
// time. The client Requests the semaphore before accessing the
|
||
|
|
// resource and Releases the semaphore when it is done. The
|
||
|
|
// same client can Request the semaphore multiple times (a nest
|
||
|
|
// count is maintained).
|
||
|
|
// The mutex semaphore is a wrapper around a critical section
|
||
|
|
// which does not support a timeout mechanism. Therefore the
|
||
|
|
// usage of any value other than INFINITE is discouraged. It
|
||
|
|
// is provided merely for compatibility.
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
class CMutexSem
|
||
|
|
{
|
||
|
|
public:
|
||
|
|
CMutexSem();
|
||
|
|
inline BOOL Init();
|
||
|
|
~CMutexSem();
|
||
|
|
|
||
|
|
SEMRESULT Request(DWORD dwMilliseconds = INFINITE);
|
||
|
|
void Release();
|
||
|
|
|
||
|
|
private:
|
||
|
|
CRITICAL_SECTION _cs;
|
||
|
|
};
|
||
|
|
|
||
|
|
//+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Class: CLock (lck)
|
||
|
|
//
|
||
|
|
// Purpose: Lock using a Mutex Semaphore
|
||
|
|
//
|
||
|
|
// History: 02-Oct-91 BartoszM Created.
|
||
|
|
//
|
||
|
|
// Notes: Simple lock object to be created on the stack.
|
||
|
|
// The constructor acquires the semaphor, the destructor
|
||
|
|
// (called when lock is going out of scope) releases it.
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
class CLock INHERIT_UNWIND_IF_CAIRO
|
||
|
|
{
|
||
|
|
EXPORTDEF DECLARE_UNWIND
|
||
|
|
|
||
|
|
public:
|
||
|
|
CLock ( CMutexSem& mxs );
|
||
|
|
~CLock ();
|
||
|
|
private:
|
||
|
|
CMutexSem& _mxs;
|
||
|
|
};
|
||
|
|
|
||
|
|
//+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Class: CEventSem (evs)
|
||
|
|
//
|
||
|
|
// Purpose: Event Semaphore services
|
||
|
|
//
|
||
|
|
// Interface: Wait - wait for semaphore to be signalled
|
||
|
|
// Set - set signalled state
|
||
|
|
// Reset - clear signalled state
|
||
|
|
// Pulse - set and clear semaphore
|
||
|
|
//
|
||
|
|
// History: 21-Jun-91 AlexT Created.
|
||
|
|
// 27-Feb-92 BartoszM Use exceptions for errors
|
||
|
|
//
|
||
|
|
// Notes: Used for communication between consumers and producers.
|
||
|
|
// Consumer threads block by calling Wait. A producer
|
||
|
|
// calls Set waking up all the consumers who go ahead
|
||
|
|
// and consume until there's nothing left. They call
|
||
|
|
// Reset, release whatever lock protected the resources,
|
||
|
|
// and call Wait. There has to be a separate lock
|
||
|
|
// to protect the shared resources.
|
||
|
|
// Remember: call Reset under lock.
|
||
|
|
// don't call Wait under lock.
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
class CEventSem
|
||
|
|
{
|
||
|
|
public:
|
||
|
|
inline CEventSem( BOOL fInitState=FALSE, const LPSECURITY_ATTRIBUTES lpsa=NULL );
|
||
|
|
inline CEventSem( HANDLE hEvent );
|
||
|
|
inline ~CEventSem();
|
||
|
|
|
||
|
|
inline ULONG Wait(DWORD dwMilliseconds = INFINITE,
|
||
|
|
BOOL fAlertable = FALSE );
|
||
|
|
inline void Set();
|
||
|
|
inline void Reset();
|
||
|
|
inline void Pulse();
|
||
|
|
inline const HANDLE GetHandle() const { return _hEvent; }
|
||
|
|
|
||
|
|
private:
|
||
|
|
HANDLE _hEvent;
|
||
|
|
};
|
||
|
|
|
||
|
|
//+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Member: CMutexSem::CMutexSem, public
|
||
|
|
//
|
||
|
|
// Synopsis: Mutex semaphore constructor
|
||
|
|
//
|
||
|
|
// Effects: Initializes the semaphores data
|
||
|
|
//
|
||
|
|
// History: 14-Jun-91 AlexT Created.
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
inline CMutexSem::CMutexSem()
|
||
|
|
{
|
||
|
|
Init();
|
||
|
|
}
|
||
|
|
|
||
|
|
inline CMutexSem::Init()
|
||
|
|
{
|
||
|
|
InitializeCriticalSection(&_cs);
|
||
|
|
return TRUE;
|
||
|
|
};
|
||
|
|
|
||
|
|
//+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Member: CMutexSem::~CMutexSem, public
|
||
|
|
//
|
||
|
|
// Synopsis: Mutex semaphore destructor
|
||
|
|
//
|
||
|
|
// Effects: Releases semaphore data
|
||
|
|
//
|
||
|
|
// History: 14-Jun-91 AlexT Created.
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
inline CMutexSem::~CMutexSem()
|
||
|
|
{
|
||
|
|
DeleteCriticalSection(&_cs);
|
||
|
|
}
|
||
|
|
|
||
|
|
//+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Member: CMutexSem::Request, public
|
||
|
|
//
|
||
|
|
// Synopsis: Acquire semaphore
|
||
|
|
//
|
||
|
|
// Effects: Asserts correct owner
|
||
|
|
//
|
||
|
|
// Arguments: [dwMilliseconds] -- Timeout value
|
||
|
|
//
|
||
|
|
// History: 14-Jun-91 AlexT Created.
|
||
|
|
//
|
||
|
|
// Notes: Uses GetCurrentTask to establish the semaphore owner, but
|
||
|
|
// written to work even if GetCurrentTask fails.
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
inline SEMRESULT CMutexSem::Request(DWORD dwMilliseconds)
|
||
|
|
{
|
||
|
|
dwMilliseconds;
|
||
|
|
|
||
|
|
EnterCriticalSection(&_cs);
|
||
|
|
return(SEMSUCCESS);
|
||
|
|
}
|
||
|
|
|
||
|
|
//+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Member: CMutexSem::Release, public
|
||
|
|
//
|
||
|
|
// Synopsis: Release semaphore
|
||
|
|
//
|
||
|
|
// Effects: Asserts correct owner
|
||
|
|
//
|
||
|
|
// History: 14-Jun-91 AlexT Created.
|
||
|
|
//
|
||
|
|
// Notes: Uses GetCurrentTask to establish the semaphore owner, but
|
||
|
|
// written to work even if GetCurrentTask fails.
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
inline void CMutexSem::Release()
|
||
|
|
{
|
||
|
|
LeaveCriticalSection(&_cs);
|
||
|
|
}
|
||
|
|
|
||
|
|
//+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Member: CLock::CLock
|
||
|
|
//
|
||
|
|
// Synopsis: Acquire semaphore
|
||
|
|
//
|
||
|
|
// History: 02-Oct-91 BartoszM Created.
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
inline CLock::CLock ( CMutexSem& mxs )
|
||
|
|
: _mxs ( mxs )
|
||
|
|
{
|
||
|
|
_mxs.Request ( INFINITE );
|
||
|
|
END_CONSTRUCTION (CLock);
|
||
|
|
}
|
||
|
|
|
||
|
|
//+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Member: CLock::~CLock
|
||
|
|
//
|
||
|
|
// Synopsis: Release semaphore
|
||
|
|
//
|
||
|
|
// History: 02-Oct-91 BartoszM Created.
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
inline CLock::~CLock ()
|
||
|
|
{
|
||
|
|
_mxs.Release();
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
//+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Member: CEventSem::CEventSem
|
||
|
|
//
|
||
|
|
// Synopsis: Creates an event
|
||
|
|
//
|
||
|
|
// Arguments: [bInitState] -- TRUE: signaled state, FALSE non-signaled
|
||
|
|
// [lpsa] -- security attributes
|
||
|
|
//
|
||
|
|
// History: 27-Feb-92 BartoszM Created
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
inline CEventSem::CEventSem ( BOOL bInitState, const LPSECURITY_ATTRIBUTES lpsa )
|
||
|
|
{
|
||
|
|
_hEvent = CreateEvent ( lpsa, TRUE, bInitState, 0 );
|
||
|
|
if ( _hEvent == 0 )
|
||
|
|
{
|
||
|
|
THROW ( CSystemException ( GetLastError() ));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
//+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Member: CEventSem::CEventSem
|
||
|
|
//
|
||
|
|
// Synopsis: Opens an event
|
||
|
|
//
|
||
|
|
// Arguments: [hEvent] -- handle of event to open
|
||
|
|
// [bInitState] -- TRUE: signaled state, FALSE non-signaled
|
||
|
|
//
|
||
|
|
// History: 02-Jul-94 DwightKr Created
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
inline CEventSem::CEventSem ( HANDLE hEvent ) : _hEvent( hEvent )
|
||
|
|
{
|
||
|
|
}
|
||
|
|
|
||
|
|
//+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Member: CEventSem::~CEventSem
|
||
|
|
//
|
||
|
|
// Synopsis: Releases event
|
||
|
|
//
|
||
|
|
// History: 27-Feb-92 BartoszM Created
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
inline CEventSem::~CEventSem ()
|
||
|
|
{
|
||
|
|
if ( !CloseHandle ( _hEvent ) )
|
||
|
|
{
|
||
|
|
THROW ( CSystemException ( GetLastError() ));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
//+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Member: CEventSem::Set
|
||
|
|
//
|
||
|
|
// Synopsis: Set the state to signaled. Wake up waiting threads.
|
||
|
|
// For manual events the state remains set
|
||
|
|
// until Reset is called
|
||
|
|
//
|
||
|
|
// History: 27-Feb-92 BartoszM Created
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
inline void CEventSem::Set()
|
||
|
|
{
|
||
|
|
if ( !SetEvent ( _hEvent ) )
|
||
|
|
{
|
||
|
|
THROW ( CSystemException ( GetLastError() ));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
//+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Member: CEventSem::Reset
|
||
|
|
//
|
||
|
|
// Synopsis: Reset the state to non-signaled. Threads will block.
|
||
|
|
//
|
||
|
|
// History: 27-Feb-92 BartoszM Created
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
inline void CEventSem::Reset()
|
||
|
|
{
|
||
|
|
if ( !ResetEvent ( _hEvent ) )
|
||
|
|
{
|
||
|
|
THROW ( CSystemException ( GetLastError() ));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
//+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Member: CEventSem::Wait
|
||
|
|
//
|
||
|
|
// Synopsis: Block until event set
|
||
|
|
//
|
||
|
|
// History: 27-Feb-92 BartoszM Created
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
inline ULONG CEventSem::Wait( DWORD msec, BOOL fAlertable )
|
||
|
|
{
|
||
|
|
DWORD res = WaitForSingleObjectEx ( _hEvent, msec, fAlertable );
|
||
|
|
|
||
|
|
if ( res == (DWORD)0xffffffff )
|
||
|
|
{
|
||
|
|
THROW ( CSystemException ( GetLastError() ));
|
||
|
|
}
|
||
|
|
return(res);
|
||
|
|
}
|
||
|
|
|
||
|
|
//+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Member: CEventSem::Pulse
|
||
|
|
//
|
||
|
|
// Synopsis: Set the state to signaled. Wake up waiting threads.
|
||
|
|
//
|
||
|
|
// History: 27-Feb-92 BartoszM Created
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
inline void CEventSem::Pulse()
|
||
|
|
{
|
||
|
|
if ( !PulseEvent ( _hEvent ) )
|
||
|
|
{
|
||
|
|
THROW ( CSystemException ( GetLastError() ));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif /* __SEM32_HXX__ */
|