/////////////////////////////////////////////////////////////////////////////
-// Name: thread.cpp
+// Name: src/msw/thread.cpp
// Purpose: wxThread Implementation
// Author: Original from Wolfram Gloger/Guilhem Lavaux
// Modified by: Vadim Zeitlin to make it work :-)
// Created: 04/22/98
// RCS-ID: $Id$
-// Copyright: (c) Wolfram Gloger (1996, 1997); Guilhem Lavaux (1998),
-// Vadim Zeitlin (1999)
+// Copyright: (c) Wolfram Gloger (1996, 1997), Guilhem Lavaux (1998);
+// Vadim Zeitlin (1999-2002)
// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
#if wxUSE_THREADS
#include "wx/msw/private.h"
+#include "wx/msw/missing.h"
#include "wx/module.h"
#include "wx/thread.h"
-#ifdef Yield
-# undef Yield
-#endif
-
// must have this symbol defined to get _beginthread/_endthread declarations
#ifndef _MT
#define _MT
#if defined(__VISUALC__) || \
(defined(__BORLANDC__) && (__BORLANDC__ >= 0x500)) || \
(defined(__GNUG__) && defined(__MSVCRT__)) || \
- defined(__WATCOMC__)
+ defined(__WATCOMC__) || defined(__MWERKS__)
#undef wxUSE_BEGIN_THREAD
#define wxUSE_BEGIN_THREAD
static bool gs_waitingForThread = FALSE;
// ============================================================================
-// Windows implementation of thread classes
+// Windows implementation of thread and related classes
// ============================================================================
// ----------------------------------------------------------------------------
-// wxMutex implementation
+// wxCriticalSection
+// ----------------------------------------------------------------------------
+
+wxCriticalSection::wxCriticalSection()
+{
+ wxCOMPILE_TIME_ASSERT( sizeof(CRITICAL_SECTION) <= sizeof(wxCritSectBuffer),
+ wxCriticalSectionBufferTooSmall );
+
+ ::InitializeCriticalSection((CRITICAL_SECTION *)m_buffer);
+}
+
+wxCriticalSection::~wxCriticalSection()
+{
+ ::DeleteCriticalSection((CRITICAL_SECTION *)m_buffer);
+}
+
+void wxCriticalSection::Enter()
+{
+ ::EnterCriticalSection((CRITICAL_SECTION *)m_buffer);
+}
+
+void wxCriticalSection::Leave()
+{
+ ::LeaveCriticalSection((CRITICAL_SECTION *)m_buffer);
+}
+
+// ----------------------------------------------------------------------------
+// wxMutex
// ----------------------------------------------------------------------------
class wxMutexInternal
{
public:
- wxMutexInternal()
- {
- m_mutex = ::CreateMutex(NULL, FALSE, NULL);
- if ( !m_mutex )
- {
- wxLogSysError(_("Can not create mutex"));
- }
- }
+ wxMutexInternal(wxMutexType mutexType);
+ ~wxMutexInternal();
- ~wxMutexInternal() { if ( m_mutex ) ::CloseHandle(m_mutex); }
+ bool IsOk() const { return m_mutex != NULL; }
+
+ wxMutexError Lock() { return LockTimeout(INFINITE); }
+ wxMutexError TryLock() { return LockTimeout(0); }
+ wxMutexError Unlock();
+
+private:
+ wxMutexError LockTimeout(DWORD milliseconds);
-public:
HANDLE m_mutex;
};
-wxMutex::wxMutex()
+// all mutexes are recursive under Win32 so we don't use mutexType
+wxMutexInternal::wxMutexInternal(wxMutexType WXUNUSED(mutexType))
{
- m_internal = new wxMutexInternal;
+ // create a nameless (hence intra process and always private) mutex
+ m_mutex = ::CreateMutex
+ (
+ NULL, // default secutiry attributes
+ FALSE, // not initially locked
+ NULL // no name
+ );
- m_locked = 0;
+ if ( !m_mutex )
+ {
+ wxLogLastError(_T("CreateMutex()"));
+ }
}
-wxMutex::~wxMutex()
+wxMutexInternal::~wxMutexInternal()
{
- if ( m_locked > 0 )
+ if ( m_mutex )
{
- wxLogDebug(_T("Warning: freeing a locked mutex (%d locks)."), m_locked);
+ if ( !::CloseHandle(m_mutex) )
+ {
+ wxLogLastError(_T("CloseHandle(mutex)"));
+ }
}
-
- delete m_internal;
}
-wxMutexError wxMutex::Lock()
+wxMutexError wxMutexInternal::LockTimeout(DWORD milliseconds)
{
- DWORD ret;
-
- ret = WaitForSingleObject(m_internal->m_mutex, INFINITE);
- switch ( ret )
+ DWORD rc = ::WaitForSingleObject(m_mutex, milliseconds);
+ if ( rc == WAIT_ABANDONED )
{
- case WAIT_ABANDONED:
- return wxMUTEX_BUSY;
+ // the previous caller died without releasing the mutex, but now we can
+ // really lock it
+ wxLogDebug(_T("WaitForSingleObject() returned WAIT_ABANDONED"));
+ // use 0 timeout, normally we should always get it
+ rc = ::WaitForSingleObject(m_mutex, 0);
+ }
+
+ switch ( rc )
+ {
case WAIT_OBJECT_0:
// ok
break;
- case WAIT_FAILED:
- wxLogSysError(_("Couldn't acquire a mutex lock"));
- return wxMUTEX_MISC_ERROR;
-
case WAIT_TIMEOUT:
+ return wxMUTEX_BUSY;
+
+ case WAIT_ABANDONED: // checked for above
default:
wxFAIL_MSG(wxT("impossible return value in wxMutex::Lock"));
- }
+ // fall through
- m_locked++;
- return wxMUTEX_NO_ERROR;
-}
-
-wxMutexError wxMutex::TryLock()
-{
- DWORD ret;
-
- ret = WaitForSingleObject(m_internal->m_mutex, 0);
- if (ret == WAIT_TIMEOUT || ret == WAIT_ABANDONED)
- return wxMUTEX_BUSY;
+ case WAIT_FAILED:
+ wxLogLastError(_T("WaitForSingleObject(mutex)"));
+ return wxMUTEX_MISC_ERROR;
+ }
- m_locked++;
return wxMUTEX_NO_ERROR;
}
-wxMutexError wxMutex::Unlock()
+wxMutexError wxMutexInternal::Unlock()
{
- if (m_locked > 0)
- m_locked--;
-
- BOOL ret = ReleaseMutex(m_internal->m_mutex);
- if ( ret == 0 )
+ if ( !::ReleaseMutex(m_mutex) )
{
- wxLogSysError(_("Couldn't release a mutex"));
+ wxLogLastError(_("ReleaseMutex()"));
+
return wxMUTEX_MISC_ERROR;
}
return wxMUTEX_NO_ERROR;
}
-// ==========================================================================
-// wxSemaphore
-// ==========================================================================
-
// --------------------------------------------------------------------------
-// wxSemaphoreInternal
+// wxSemaphore
// --------------------------------------------------------------------------
+// a trivial wrapper around Win32 semaphore
class wxSemaphoreInternal
{
public:
- wxSemaphoreInternal( int initialcount = 0, int maxcount = 0 );
+ wxSemaphoreInternal(int initialcount, int maxcount);
~wxSemaphoreInternal();
- void Wait();
- bool TryWait();
+ bool IsOk() const { return m_semaphore != NULL; }
- bool Wait( unsigned long timeout_millis );
+ wxSemaError Wait() { return WaitTimeout(INFINITE); }
+ wxSemaError TryWait() { return WaitTimeout(0); }
+ wxSemaError WaitTimeout(unsigned long milliseconds);
- void Post();
+ wxSemaError Post();
private:
HANDLE m_semaphore;
};
-wxSemaphoreInternal::wxSemaphoreInternal( int initialcount, int maxcount )
+wxSemaphoreInternal::wxSemaphoreInternal(int initialcount, int maxcount)
{
if ( maxcount == 0 )
{
maxcount = INT_MAX;
}
- m_semaphore = ::CreateSemaphore( NULL, initialcount, maxcount, NULL );
+ m_semaphore = ::CreateSemaphore
+ (
+ NULL, // default security attributes
+ initialcount,
+ maxcount,
+ NULL // no name
+ );
+
if ( !m_semaphore )
{
wxLogLastError(_T("CreateSemaphore()"));
wxSemaphoreInternal::~wxSemaphoreInternal()
{
- CloseHandle( m_semaphore );
-}
-
-void wxSemaphoreInternal::Wait()
-{
- if ( ::WaitForSingleObject( m_semaphore, INFINITE ) != WAIT_OBJECT_0 )
+ if ( m_semaphore )
{
- wxLogLastError(_T("WaitForSingleObject"));
+ if ( !::CloseHandle(m_semaphore) )
+ {
+ wxLogLastError(_T("CloseHandle(semaphore)"));
+ }
}
}
-bool wxSemaphoreInternal::TryWait()
-{
- return Wait(0);
-}
-
-bool wxSemaphoreInternal::Wait( unsigned long timeout_millis )
+wxSemaError wxSemaphoreInternal::WaitTimeout(unsigned long milliseconds)
{
- DWORD result = ::WaitForSingleObject( m_semaphore, timeout_millis );
+ DWORD rc = ::WaitForSingleObject( m_semaphore, milliseconds );
- switch ( result )
+ switch ( rc )
{
case WAIT_OBJECT_0:
- return TRUE;
+ return wxSEMA_NO_ERROR;
case WAIT_TIMEOUT:
- break;
+ return wxSEMA_BUSY;
default:
- wxLogLastError(_T("WaitForSingleObject()"));
+ wxLogLastError(_T("WaitForSingleObject(semaphore)"));
}
- return FALSE;
+ return wxSEMA_MISC_ERROR;
}
-void wxSemaphoreInternal::Post()
+wxSemaError wxSemaphoreInternal::Post()
{
- if ( !::ReleaseSemaphore( m_semaphore, 1, NULL ) )
+ if ( !::ReleaseSemaphore(m_semaphore, 1, NULL /* ptr to previous count */) )
{
wxLogLastError(_T("ReleaseSemaphore"));
- }
-}
-
-// --------------------------------------------------------------------------
-// wxSemaphore
-// --------------------------------------------------------------------------
-
-wxSemaphore::wxSemaphore( int initialcount, int maxcount )
-{
- m_internal = new wxSemaphoreInternal( initialcount, maxcount );
-}
-
-wxSemaphore::~wxSemaphore()
-{
- delete m_internal;
-}
-
-void wxSemaphore::Wait()
-{
- m_internal->Wait();
-}
-
-bool wxSemaphore::TryWait()
-{
- return m_internal->TryWait();
-}
-bool wxSemaphore::Wait( unsigned long timeout_millis )
-{
- return m_internal->Wait( timeout_millis );
-}
+ return wxSEMA_MISC_ERROR;
+ }
-void wxSemaphore::Post()
-{
- m_internal->Post();
+ return wxSEMA_NO_ERROR;
}
-
-// ==========================================================================
-// wxCondition
-// ==========================================================================
-
// --------------------------------------------------------------------------
-// wxConditionInternal
+// wxCondition
// --------------------------------------------------------------------------
+// Win32 doesn't have explicit support for the POSIX condition variables and
+// the Win32 events have quite different semantics, so we reimplement the
+// conditions from scratch using the mutexes and semaphores
class wxConditionInternal
{
public:
- wxConditionInternal( wxMutex *mutex );
- ~wxConditionInternal();
-
- void Wait();
+ wxConditionInternal(wxMutex& mutex);
- bool Wait( unsigned long timeout_millis );
+ bool IsOk() const { return m_mutex.IsOk() && m_semaphore.IsOk(); }
- void Signal();
+ wxCondError Wait();
+ wxCondError WaitTimeout(unsigned long milliseconds);
- void Broadcast();
+ wxCondError Signal();
+ wxCondError Broadcast();
private:
- int m_numWaiters;
- wxMutex m_mutexNumWaiters;
+ // the number of threads currently waiting for this condition
+ LONG m_numWaiters;
- wxMutex *m_mutex;
+ // the critical section protecting m_numWaiters
+ wxCriticalSection m_csWaiters;
+ wxMutex& m_mutex;
wxSemaphore m_semaphore;
};
-wxConditionInternal::wxConditionInternal( wxMutex *mutex )
+wxConditionInternal::wxConditionInternal(wxMutex& mutex)
+ : m_mutex(mutex)
{
- m_mutex = mutex;
-
+ // another thread can't access it until we return from ctor, so no need to
+ // protect access to m_numWaiters here
m_numWaiters = 0;
}
-wxConditionInternal::~wxConditionInternal()
-{
-}
-
-void wxConditionInternal::Wait()
+wxCondError wxConditionInternal::Wait()
{
// increment the number of waiters
- m_mutexNumWaiters.Lock();
- m_numWaiters++;
- m_mutexNumWaiters.Unlock();
+ ::InterlockedIncrement(&m_numWaiters);
- m_mutex->Unlock();
+ m_mutex.Unlock();
// a potential race condition can occur here
//
// can 'remember' signals the race condition will not occur
// wait ( if necessary ) and decrement semaphore
- m_semaphore.Wait();
+ wxSemaError err = m_semaphore.Wait();
+ m_mutex.Lock();
- m_mutex->Lock();
+ return err == wxSEMA_NO_ERROR ? wxCOND_NO_ERROR : wxCOND_MISC_ERROR;
}
-bool wxConditionInternal::Wait( unsigned long timeout_millis )
+wxCondError wxConditionInternal::WaitTimeout(unsigned long milliseconds)
{
- m_mutexNumWaiters.Lock();
- m_numWaiters++;
- m_mutexNumWaiters.Unlock();
+ ::InterlockedIncrement(&m_numWaiters);
- m_mutex->Unlock();
+ m_mutex.Unlock();
// a race condition can occur at this point in the code
//
// please see the comments in Wait(), for details
- bool success = TRUE;
+ wxSemaError err = m_semaphore.WaitTimeout(milliseconds);
- bool result = m_semaphore.Wait( timeout_millis );
-
- if ( !result )
+ if ( err == wxSEMA_BUSY )
{
// another potential race condition exists here it is caused when a
// 'waiting' thread timesout, and returns from WaitForSingleObject, but
// 'nwaiters_mutex'. this call does not block because of the zero
// timeout, but will allow the waiting thread to catch the missed
// signals.
- m_mutexNumWaiters.Lock();
- result = m_semaphore.Wait( 0 );
+ wxCriticalSectionLocker lock(m_csWaiters);
+
+ err = m_semaphore.WaitTimeout(0);
- if ( !result )
+ if ( err != wxSEMA_NO_ERROR )
{
m_numWaiters--;
- success = FALSE;
}
-
- m_mutexNumWaiters.Unlock();
}
- m_mutex->Lock();
+ m_mutex.Lock();
- return success;
+ return err == wxSEMA_NO_ERROR ? wxCOND_NO_ERROR : wxCOND_MISC_ERROR;
}
-void wxConditionInternal::Signal()
+wxCondError wxConditionInternal::Signal()
{
- m_mutexNumWaiters.Lock();
+ wxCriticalSectionLocker lock(m_csWaiters);
if ( m_numWaiters > 0 )
{
// increment the semaphore by 1
- m_semaphore.Post();
+ if ( m_semaphore.Post() != wxSEMA_NO_ERROR )
+ return wxCOND_MISC_ERROR;
m_numWaiters--;
}
- m_mutexNumWaiters.Unlock();
+ return wxCOND_NO_ERROR;
}
-void wxConditionInternal::Broadcast()
+wxCondError wxConditionInternal::Broadcast()
{
- m_mutexNumWaiters.Lock();
+ wxCriticalSectionLocker lock(m_csWaiters);
while ( m_numWaiters > 0 )
{
- m_semaphore.Post();
+ if ( m_semaphore.Post() != wxSEMA_NO_ERROR )
+ return wxCOND_MISC_ERROR;
+
m_numWaiters--;
}
- m_mutexNumWaiters.Unlock();
-}
-
-// ----------------------------------------------------------------------------
-// wxCondition implementation
-// ----------------------------------------------------------------------------
-
-wxCondition::wxCondition( wxMutex *mutex )
-{
- if ( !mutex )
- {
- wxFAIL_MSG( _T("NULL mutex in wxCondition ctor") );
-
- m_internal = NULL;
- }
- else
- {
- m_internal = new wxConditionInternal( mutex );
- }
-}
-
-wxCondition::~wxCondition()
-{
- delete m_internal;
-}
-
-void wxCondition::Wait()
-{
- if ( m_internal )
- m_internal->Wait();
-}
-
-bool wxCondition::Wait( unsigned long timeout_millis )
-{
- return m_internal ? m_internal->Wait(timeout_millis) : FALSE;
-}
-
-void wxCondition::Signal()
-{
- if ( m_internal )
- m_internal->Signal();
-}
-
-void wxCondition::Broadcast()
-{
- if ( m_internal )
- m_internal->Broadcast();
-}
-
-// ----------------------------------------------------------------------------
-// wxCriticalSection implementation
-// ----------------------------------------------------------------------------
-
-wxCriticalSection::wxCriticalSection()
-{
-#ifdef __WXDEBUG__
- // Done this way to stop warnings during compilation about statement
- // always being FALSE
- int csSize = sizeof(CRITICAL_SECTION);
- int bSize = sizeof(m_buffer);
- wxASSERT_MSG( csSize <= bSize,
- _T("must increase buffer size in wx/thread.h") );
-#endif
-
- ::InitializeCriticalSection((CRITICAL_SECTION *)m_buffer);
-}
-
-wxCriticalSection::~wxCriticalSection()
-{
- ::DeleteCriticalSection((CRITICAL_SECTION *)m_buffer);
-}
-
-void wxCriticalSection::Enter()
-{
- ::EnterCriticalSection((CRITICAL_SECTION *)m_buffer);
-}
-
-void wxCriticalSection::Leave()
-{
- ::LeaveCriticalSection((CRITICAL_SECTION *)m_buffer);
+ return wxCOND_NO_ERROR;
}
// ----------------------------------------------------------------------------
{
// set flag for wxIsWaitingForThread()
gs_waitingForThread = TRUE;
-
-#if wxUSE_GUI
- wxBeginBusyCursor();
-#endif // wxUSE_GUI
}
// ask the thread to terminate
// we can't just wait for the thread to terminate because it might be
// calling some GUI functions and so it will never terminate before we
// process the Windows messages that result from these functions
- DWORD result;
+ DWORD result = 0; // suppress warnings from broken compilers
do
{
+ if ( IsMain() )
+ {
+ // give the thread we're waiting for chance to do the GUI call
+ // it might be in
+ if ( (gs_nWaitingForGui > 0) && wxGuiOwnedByMainThread() )
+ {
+ wxMutexGuiLeave();
+ }
+ }
+
result = ::MsgWaitForMultipleObjects
(
1, // number of objects to wait for
&hThread, // the objects
FALSE, // don't wait for all objects
INFINITE, // no timeout
- QS_ALLEVENTS // return as soon as there are any events
+ QS_ALLINPUT | // return as soon as there are any events
+ QS_ALLPOSTMESSAGE
);
switch ( result )
return wxTHREAD_KILLED;
}
-
- if ( IsMain() )
- {
- // give the thread we're waiting for chance to exit
- // from the GUI call it might have been in
- if ( (gs_nWaitingForGui > 0) && wxGuiOwnedByMainThread() )
- {
- wxMutexGuiLeave();
- }
- }
-
break;
default:
if ( IsMain() )
{
gs_waitingForThread = FALSE;
-
-#if wxUSE_GUI
- wxEndBusyCursor();
-#endif // wxUSE_GUI
}
}
- if ( !::GetExitCodeThread(hThread, (LPDWORD)&rc) )
+ // although the thread might be already in the EXITED state it might not
+ // have terminated yet and so we are not sure that it has actually
+ // terminated if the "if" above hadn't been taken
+ do
{
- wxLogLastError(wxT("GetExitCodeThread"));
+ if ( !::GetExitCodeThread(hThread, (LPDWORD)&rc) )
+ {
+ wxLogLastError(wxT("GetExitCodeThread"));
- rc = (ExitCode)-1;
- }
+ rc = (ExitCode)-1;
+ }
+ } while ( (DWORD)rc == STILL_ACTIVE );
if ( IsDetached() )
{
delete this;
}
- wxASSERT_MSG( (DWORD)rc != STILL_ACTIVE,
- wxT("thread must be already terminated.") );
-
if ( pRc )
*pRc = rc;
return gs_waitingForThread;
}
+// ----------------------------------------------------------------------------
+// include common implementation code
+// ----------------------------------------------------------------------------
+
+#include "wx/thrimpl.cpp"
+
#endif // wxUSE_THREADS
-// vi:sts=4:sw=4:et
projects / wxWidgets.git / blobdiff