public:
wxConditionInternal()
{
- event = ::CreateEvent(
- NULL, // default secutiry
- FALSE, // not manual reset
- FALSE, // nonsignaled initially
- NULL // nameless event
- );
- if ( !event )
+ m_hEvent = ::CreateEvent(
+ NULL, // default secutiry
+ FALSE, // not manual reset
+ FALSE, // nonsignaled initially
+ NULL // nameless event
+ );
+ if ( !m_hEvent )
{
wxLogSysError(_("Can not create event object."));
}
- waiters = 0;
+
+ // nobody waits for us yet
+ m_nWaiters = 0;
}
bool Wait(DWORD timeout)
{
- waiters++;
+ // as m_nWaiters variable is accessed from multiple waiting threads
+ // (and possibly from the broadcasting thread), we need to change its
+ // value atomically
+ ::InterlockedIncrement(&m_nWaiters);
- // FIXME this should be MsgWaitForMultipleObjects() as well probably
- DWORD rc = ::WaitForSingleObject(event, timeout);
+ // FIXME this should be MsgWaitForMultipleObjects() as we want to keep
+ // processing Windows messages while waiting (or don't we?)
+ DWORD rc = ::WaitForSingleObject(m_hEvent, timeout);
- waiters--;
+ ::InterlockedDecrement(&m_nWaiters);
return rc != WAIT_TIMEOUT;
}
+ void Signal()
+ {
+ // set the event to signaled: if a thread is already waiting on it, it
+ // will be woken up, otherwise the event will remain in the signaled
+ // state until someone waits on it. In any case, the system will return
+ // it to a non signalled state afterwards. If multiple threads are
+ // waiting, only one will be woken up.
+ if ( !::SetEvent(m_hEvent) )
+ {
+ wxLogLastError(wxT("SetEvent"));
+ }
+ }
+
+ void Broadcast()
+ {
+ // we need to save the original value as m_nWaiters is goign to be
+ // decreased by the signalled thread resulting in the loop being
+ // executed less times than needed
+ LONG nWaiters = m_nWaiters;
+
+ // this works because all these threads are already waiting and so each
+ // SetEvent() inside Signal() is really a PulseEvent() because the
+ // event state is immediately returned to non-signaled
+ for ( LONG n = 0; n < nWaiters; n++ )
+ {
+ Signal();
+ }
+ }
+
~wxConditionInternal()
{
- if ( event )
+ if ( m_hEvent )
{
- if ( !::CloseHandle(event) )
+ if ( !::CloseHandle(m_hEvent) )
{
- wxLogLastError("CloseHandle(event)");
+ wxLogLastError(wxT("CloseHandle(event)"));
}
}
}
- HANDLE event;
- int waiters;
+private:
+ // the Win32 synchronization object corresponding to this event
+ HANDLE m_hEvent;
+
+ // number of threads waiting for this condition
+ LONG m_nWaiters;
};
wxCondition::wxCondition()
void wxCondition::Signal()
{
- // set the event to signaled: if a thread is already waiting on it, it will
- // be woken up, otherwise the event will remain in the signaled state until
- // someone waits on it. In any case, the system will return it to a non
- // signalled state afterwards. If multiple threads are waiting, only one
- // will be woken up.
- if ( !::SetEvent(m_internal->event) )
- {
- wxLogLastError("SetEvent");
- }
+ m_internal->Signal();
}
void wxCondition::Broadcast()
{
- // this works because all these threads are already waiting and so each
- // SetEvent() inside Signal() is really a PulseEvent() because the event
- // state is immediately returned to non-signaled
- for ( int i = 0; i < m_internal->waiters; i++ )
- {
- Signal();
- }
+ m_internal->Broadcast();
}
// ----------------------------------------------------------------------------
{
if ( !::CloseHandle(m_hThread) )
{
- wxLogLastError("CloseHandle(thread)");
+ wxLogLastError(wxT("CloseHandle(thread)"));
}
m_hThread = 0;
DWORD wxThreadInternal::WinThreadStart(wxThread *thread)
{
- // first of all, check whether we hadn't been cancelled already
+ DWORD rc;
+ bool wasCancelled;
+
+ // first of all, check whether we hadn't been cancelled already and don't
+ // start the user code at all then
if ( thread->m_internal->GetState() == STATE_EXITED )
{
- return (DWORD)-1;
+ rc = (DWORD)-1;
+ wasCancelled = TRUE;
}
-
- // store the thread object in the TLS
- if ( !::TlsSetValue(gs_tlsThisThread, thread) )
+ else // do run thread
{
- wxLogSysError(_("Can not start thread: error writing TLS."));
+ // store the thread object in the TLS
+ if ( !::TlsSetValue(gs_tlsThisThread, thread) )
+ {
+ wxLogSysError(_("Can not start thread: error writing TLS."));
- return (DWORD)-1;
- }
+ return (DWORD)-1;
+ }
- DWORD rc = (DWORD)thread->Entry();
+ rc = (DWORD)thread->Entry();
- // enter m_critsect before changing the thread state
- thread->m_critsect.Enter();
- bool wasCancelled = thread->m_internal->GetState() == STATE_CANCELED;
- thread->m_internal->SetState(STATE_EXITED);
- thread->m_critsect.Leave();
+ // enter m_critsect before changing the thread state
+ thread->m_critsect.Enter();
+ wasCancelled = thread->m_internal->GetState() == STATE_CANCELED;
+ thread->m_internal->SetState(STATE_EXITED);
+ thread->m_critsect.Leave();
+ }
thread->OnExit();
- // if the thread was cancelled (from Delete()), then it the handle is still
+ // if the thread was cancelled (from Delete()), then its handle is still
// needed there
if ( thread->IsDetached() && !wasCancelled )
{
return FALSE;
}
- m_state = STATE_RUNNING;
+ // don't change the state from STATE_EXITED because it's special and means
+ // we are going to terminate without running any user code - if we did it,
+ // the codei n Delete() wouldn't work
+ if ( m_state != STATE_EXITED )
+ {
+ m_state = STATE_RUNNING;
+ }
return TRUE;
}
if ( hModKernel )
{
pfnSetProcessAffinityMask = (SETPROCESSAFFINITYMASK)
- ::GetProcAddress(hModKernel,
-#if defined(__BORLANDC__) && (__BORLANDC__ <= 0x520)
- "SetProcessAffinityMask");
-#else
- _T("SetProcessAffinityMask"));
-#endif
+ ::GetProcAddress(hModKernel, "SetProcessAffinityMask");
}
// we've discovered a MT version of Win9x!
wxASSERT_MSG( pfnSetProcessAffinityMask,
- _T("this system has several CPUs but no "
- "SetProcessAffinityMask function?") );
+ _T("this system has several CPUs but no SetProcessAffinityMask function?") );
}
if ( !pfnSetProcessAffinityMask )
// Delete() is always safe to call, so consider all possible states
- // has the thread started to run?
- bool shouldResume = FALSE;
+ // we might need to resume the thread, but we might also not need to cancel
+ // it if it doesn't run yet
+ bool shouldResume = FALSE,
+ shouldCancel = TRUE,
+ isRunning = FALSE;
+ // check if the thread already started to run
{
wxCriticalSectionLocker lock(m_critsect);
if ( m_internal->GetState() == STATE_NEW )
{
- // WinThreadStart() will see it and terminate immediately
+ // WinThreadStart() will see it and terminate immediately, no need
+ // to cancel the thread - but we still need to resume it to let it
+ // run
m_internal->SetState(STATE_EXITED);
- shouldResume = TRUE;
+ Resume(); // it knows about STATE_EXITED special case
+
+ shouldCancel = FALSE;
+ isRunning = TRUE;
+
+ // shouldResume is correctly set to FALSE here
+ }
+ else
+ {
+ shouldResume = IsPaused();
}
}
- // is the thread paused?
- if ( shouldResume || IsPaused() )
+ // resume the thread if it is paused
+ if ( shouldResume )
Resume();
HANDLE hThread = m_internal->GetHandle();
// does is still run?
- if ( IsRunning() )
+ if ( isRunning || IsRunning() )
{
if ( IsMain() )
{
}
// ask the thread to terminate
+ if ( shouldCancel )
{
wxCriticalSectionLocker lock(m_critsect);
if ( !::GetExitCodeThread(hThread, (LPDWORD)&rc) )
{
- wxLogLastError("GetExitCodeThread");
+ wxLogLastError(wxT("GetExitCodeThread"));
rc = (ExitCode)-1;
}
{
// if the thread exits normally, this is done in WinThreadStart, but in
// this case it would have been too early because
- // MsgWaitForMultipleObject() would fail if the therad handle was
+ // MsgWaitForMultipleObject() would fail if the thread handle was
// closed while we were waiting on it, so we must do it here
delete this;
}
// in normal circumstances it will only happen if all other
// TLS_MINIMUM_AVAILABLE (>= 64) indices are already taken - in other
// words, this should never happen
- wxLogSysError(_("Thread module initialization failed: "
- "impossible to allocate index in thread "
- "local storage"));
+ wxLogSysError(_("Thread module initialization failed: impossible to allocate index in thread local storage"));
return FALSE;
}
::TlsFree(gs_tlsThisThread);
gs_tlsThisThread = 0xFFFFFFFF;
- wxLogSysError(_("Thread module initialization failed: "
- "can not store value in thread local storage"));
+ wxLogSysError(_("Thread module initialization failed: can not store value in thread local storage"));
return FALSE;
}
{
if ( !::TlsFree(gs_tlsThisThread) )
{
- wxLogLastError("TlsFree failed.");
+ wxLogLastError(wxT("TlsFree failed."));
}
if ( gs_critsectGui )
}
else
{
- // decrement the number of waiters now
+ // decrement the number of threads waiting for GUI access now
wxASSERT_MSG( gs_nWaitingForGui > 0,
wxT("calling wxMutexGuiLeave() without entering it first?") );
if ( !::PostThreadMessage(gs_idMainThread, WM_NULL, 0, 0) )
{
// should never happen
- wxLogLastError("PostThreadMessage(WM_NULL)");
+ wxLogLastError(wxT("PostThreadMessage(WM_NULL)"));
}
}
projects / wxWidgets.git / blobdiff