mingw32 compilation fixes

[wxWidgets.git] / src / os2 / thread.cpp

diff --git a/src/os2/thread.cpp b/src/os2/thread.cpp
index 34ad1a4f14ad02ddcb343efea7d17dbca7ea45db..80eef6b2e2dc60e88844396744aec0a1a6347f8e 100644 (file)
--- a/src/os2/thread.cpp
+++ b/src/os2/thread.cpp
@@ -2,264 +2,780 @@
 // Name:        thread.cpp
 // Purpose:     wxThread Implementation. For Unix ports, see e.g. src/gtk
 // Author:      Original from Wolfram Gloger/Guilhem Lavaux
 // Name:        thread.cpp
 // Purpose:     wxThread Implementation. For Unix ports, see e.g. src/gtk
 // Author:      Original from Wolfram Gloger/Guilhem Lavaux

-// Modified by:
+// Modified by: David Webster

 // Created:     04/22/98
 // RCS-ID:      $Id$
 // Copyright:   (c) Wolfram Gloger (1996, 1997); Guilhem Lavaux (1998)
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
 // Created:     04/22/98
 // RCS-ID:      $Id$
 // Copyright:   (c) Wolfram Gloger (1996, 1997); Guilhem Lavaux (1998)
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 

-#ifdef __GNUG__
-#pragma implementation "thread.h"
-#endif
+// ----------------------------------------------------------------------------
+// headers
+// ----------------------------------------------------------------------------
+
+// For compilers that support precompilation, includes "wx.h".
+#include "wx/wxprec.h"
+
+#if wxUSE_THREADS
+
+#include <stdio.h>

 
 #include "wx/module.h"
 #include "wx/thread.h"
 
 #include "wx/module.h"
 #include "wx/thread.h"

-#include "wx/utils.h"

 
 

-#if wxUSE_THREADS
+#define INCL_DOSSEMAPHORES
+#define INCL_DOSPROCESS
+#define INCL_ERRORS
+#include <os2.h>
+#include <bseerr.h>

 
 

-enum thread_state {
-  STATE_IDLE = 0,
-  STATE_RUNNING,
-  STATE_CANCELED,
-  STATE_EXITED
+// the possible states of the thread ("=>" shows all possible transitions from
+// this state)
+enum wxThreadState
+{
+    STATE_NEW,          // didn't start execution yet (=> RUNNING)
+    STATE_RUNNING,      // thread is running (=> PAUSED, CANCELED)
+    STATE_PAUSED,       // thread is temporarily suspended (=> RUNNING)
+    STATE_CANCELED,     // thread should terminate a.s.a.p. (=> EXITED)
+    STATE_EXITED        // thread is terminating

 };
 
 };
 

-/////////////////////////////////////////////////////////////////////////////
-// Static variables
-/////////////////////////////////////////////////////////////////////////////
+// ----------------------------------------------------------------------------
+// static variables
+// ----------------------------------------------------------------------------

 
 

-wxMutex *wxMainMutex; // controls access to all GUI functions
+// id of the main thread - the one which can call GUI functions without first
+// calling wxMutexGuiEnter()
+static ULONG                        s_ulIdMainThread = 0;
+wxMutex*                            p_wxMainMutex;

 
 

-/////////////////////////////////////////////////////////////////////////////
-// Windows implementation
-/////////////////////////////////////////////////////////////////////////////
+// OS2 substitute for Tls pointer the current parent thread object
+wxThread*                           m_pThread;    // pointer to the wxWindows thread object
+
+// if it's FALSE, some secondary thread is holding the GUI lock
+static bool s_bGuiOwnedByMainThread = TRUE;
+
+// critical section which controls access to all GUI functions: any secondary
+// thread (i.e. except the main one) must enter this crit section before doing
+// any GUI calls
+static wxCriticalSection *s_pCritsectGui = NULL;
+
+// critical section which protects s_nWaitingForGui variable
+static wxCriticalSection *s_pCritsectWaitingForGui = NULL;
+
+// number of threads waiting for GUI in wxMutexGuiEnter()
+static size_t s_nWaitingForGui = 0;

 
 

-class wxMutexInternal {
+// are we waiting for a thread termination?
+static bool s_bWaitingForThread = FALSE;
+
+// ============================================================================
+// OS/2 implementation of thread classes
+// ============================================================================
+
+// ----------------------------------------------------------------------------
+// wxMutex implementation
+// ----------------------------------------------------------------------------
+class wxMutexInternal
+{

 public:
 public:

-  // TODO: internal mutex handle
+    HMTX                            m_vMutex;

 };
 
 wxMutex::wxMutex()
 {
 };
 
 wxMutex::wxMutex()
 {

+    APIRET                          ulrc;
+

     p_internal = new wxMutexInternal;
     p_internal = new wxMutexInternal;

-    // TODO: create internal mutext handle
+    ulrc = ::DosCreateMutexSem(NULL, &p_internal->m_vMutex, 0L, FALSE);
+    if (ulrc != 0)
+    {
+        wxLogSysError(_("Can not create mutex."));
+    }

     m_locked = 0;
 }
 
 wxMutex::~wxMutex()
 {
     if (m_locked > 0)
     m_locked = 0;
 }
 
 wxMutex::~wxMutex()
 {
     if (m_locked > 0)

-        wxDebugMsg("wxMutex warning: freeing a locked mutex (%d locks)\n", m_locked);
-    // TODO: free internal mutext handle
+        wxLogDebug(wxT("Warning: freeing a locked mutex (%d locks)."), m_locked);
+    ::DosCloseMutexSem(p_internal->m_vMutex);
+    p_internal->m_vMutex = NULL;

 }
 
 wxMutexError wxMutex::Lock()
 {
 }
 
 wxMutexError wxMutex::Lock()
 {

-    // TODO
+    APIRET                          ulrc;
+
+    ulrc = ::DosRequestMutexSem(p_internal->m_vMutex, SEM_INDEFINITE_WAIT);
+
+    switch (ulrc)
+    {
+        case ERROR_TOO_MANY_SEM_REQUESTS:
+            return wxMUTEX_BUSY;
+
+        case NO_ERROR:
+            // ok
+            break;
+
+        case ERROR_INVALID_HANDLE:
+        case ERROR_INTERRUPT:
+        case ERROR_SEM_OWNER_DIED:
+            wxLogSysError(_("Couldn't acquire a mutex lock"));
+            return wxMUTEX_MISC_ERROR;
+
+        case ERROR_TIMEOUT:
+        default:
+            wxFAIL_MSG(wxT("impossible return value in wxMutex::Lock"));
+    }

     m_locked++;
     return wxMUTEX_NO_ERROR;
 }
 
 wxMutexError wxMutex::TryLock()
 {
     m_locked++;
     return wxMUTEX_NO_ERROR;
 }
 
 wxMutexError wxMutex::TryLock()
 {

-    // TODO
+    ULONG                           ulrc;
+
+    ulrc = ::DosRequestMutexSem(p_internal->m_vMutex, SEM_IMMEDIATE_RETURN /*0L*/);
+    if (ulrc == ERROR_TIMEOUT || ulrc == ERROR_TOO_MANY_SEM_REQUESTS)
+        return wxMUTEX_BUSY;
+

     m_locked++;
     return wxMUTEX_NO_ERROR;
 }
 
 wxMutexError wxMutex::Unlock()
 {
     m_locked++;
     return wxMUTEX_NO_ERROR;
 }
 
 wxMutexError wxMutex::Unlock()
 {

+    APIRET                          ulrc;
+

     if (m_locked > 0)
         m_locked--;
 
     if (m_locked > 0)
         m_locked--;
 

-    // TODO
+    ulrc = ::DosReleaseMutexSem(p_internal->m_vMutex);
+    if (ulrc != 0)
+    {
+        wxLogSysError(_("Couldn't release a mutex"));
+        return wxMUTEX_MISC_ERROR;
+    }

     return wxMUTEX_NO_ERROR;
 }
 
     return wxMUTEX_NO_ERROR;
 }
 

-class wxConditionInternal {
+// ----------------------------------------------------------------------------
+// wxCondition implementation
+// ----------------------------------------------------------------------------
+
+class wxConditionInternal
+{

 public:
 public:

-  // TODO: internal handle
-  int waiters;
+    HEV                             m_vEvent;
+    int                             m_nWaiters;

 };
 
 wxCondition::wxCondition()
 {
 };
 
 wxCondition::wxCondition()
 {

+    APIRET                          ulrc;
+    ULONG                           ulCount;
+

     p_internal = new wxConditionInternal;
     p_internal = new wxConditionInternal;

-    // TODO: create internal handle
-    p_internal->waiters = 0;
+    ulrc = ::DosCreateEventSem(NULL, &p_internal->m_vEvent, 0L, FALSE);
+    if (ulrc != 0)
+    {
+        wxLogSysError(_("Can not create event object."));
+    }
+    p_internal->m_nWaiters = 0;
+    // ?? just for good measure?
+    ::DosResetEventSem(p_internal->m_vEvent, &ulCount);

 }
 
 wxCondition::~wxCondition()
 {
 }
 
 wxCondition::~wxCondition()
 {

-    // TODO: destroy internal handle
+    ::DosCloseEventSem(p_internal->m_vEvent);
+    delete p_internal;
+    p_internal = NULL;

 }
 
 }
 

-void wxCondition::Wait(wxMutex& mutex)
+void wxCondition::Wait(
+  wxMutex&                          rMutex
+)

 {
 {

-    mutex.Unlock();
-    p_internal->waiters++;
-    // TODO wait here
-    p_internal->waiters--;
-    mutex.Lock();
+    rMutex.Unlock();
+    p_internal->m_nWaiters++;
+    ::DosWaitEventSem(p_internal->m_vEvent, SEM_INDEFINITE_WAIT);
+    p_internal->m_nWaiters--;
+    rMutex.Lock();

 }
 
 }
 

-bool wxCondition::Wait(wxMutex& mutex, unsigned long sec,
-                       unsigned long nsec)
+bool wxCondition::Wait(
+  wxMutex&                          rMutex
+, unsigned long                     ulSec
+, unsigned long                     ulMillisec)

 {
 {

-    mutex.Unlock();
-    p_internal->waiters++;
+    APIRET                          ulrc;

 
 

-    // TODO wait here
-    p_internal->waiters--;
-    mutex.Lock();
+    rMutex.Unlock();
+    p_internal->m_nWaiters++;
+    ulrc = ::DosWaitEventSem(p_internal->m_vEvent, ULONG((ulSec * 1000L) + ulMillisec));
+    p_internal->m_nWaiters--;
+    rMutex.Lock();

 
 

-    return FALSE;
+    return (ulrc != ERROR_TIMEOUT);

 }
 
 void wxCondition::Signal()
 {
 }
 
 void wxCondition::Signal()
 {

-    // TODO
+    ::DosPostEventSem(p_internal->m_vEvent);

 }
 
 void wxCondition::Broadcast()
 {
 }
 
 void wxCondition::Broadcast()
 {

-    // TODO
+    int                             i;
+
+    for (i = 0; i < p_internal->m_nWaiters; i++)
+    {
+        if (::DosPostEventSem(p_internal->m_vEvent) != 0)
+        {
+            wxLogSysError(_("Couldn't change the state of event object."));
+        }
+    }

 }
 
 }
 

-class wxThreadInternal {
+// ----------------------------------------------------------------------------
+// wxCriticalSection implementation
+// ----------------------------------------------------------------------------
+
+class wxCriticalSectionInternal
+{

 public:
 public:

-    // TODO
+    // init the critical section object
+    wxCriticalSectionInternal()
+        { }
+
+    // free the associated ressources
+    ~wxCriticalSectionInternal()
+        { }
+
+private:

 };
 
 };
 

+// ----------------------------------------------------------------------------
+// wxCriticalSection implementation
+// ----------------------------------------------------------------------------
+
+wxCriticalSection::wxCriticalSection()
+{
+    m_critsect = new wxCriticalSectionInternal;
+}
+
+wxCriticalSection::~wxCriticalSection()
+{
+    delete m_critsect;
+}
+
+void wxCriticalSection::Enter()
+{
+    ::DosEnterCritSec();
+}
+
+void wxCriticalSection::Leave()
+{
+    ::DosExitCritSec();
+}
+
+// ----------------------------------------------------------------------------
+// wxThread implementation
+// ----------------------------------------------------------------------------
+
+// wxThreadInternal class
+// ----------------------
+
+class wxThreadInternal
+{
+public:
+    inline wxThreadInternal()
+    {
+        m_hThread = 0;
+        m_eState = STATE_NEW;
+        m_nPriority = 0;
+    }
+
+    // create a new (suspended) thread (for the given thread object)
+    bool Create(wxThread* pThread);
+
+    // suspend/resume/terminate
+    bool Suspend();
+    bool Resume();
+    inline void Cancel() { m_eState = STATE_CANCELED; }
+
+    // thread state
+    inline void SetState(wxThreadState eState) { m_eState = eState; }
+    inline wxThreadState GetState() const { return m_eState; }
+
+    // thread priority
+    inline void SetPriority(unsigned int nPriority) { m_nPriority = nPriority; }
+    inline unsigned int GetPriority() const { return m_nPriority; }
+
+    // thread handle and id
+    inline TID GetHandle() const { return m_hThread; }
+    TID  GetId() const { return m_hThread; }
+
+    // thread function
+    static DWORD OS2ThreadStart(wxThread *thread);
+
+private:
+    // Threads in OS/2 have only an ID, so m_hThread is both it's handle and ID
+    // PM also has no real Tls mechanism to index pointers by so we'll just
+    // keep track of the wxWindows parent object here.
+    TID                             m_hThread;    // handle and ID of the thread
+    wxThreadState                   m_eState;     // state, see wxThreadState enum
+    unsigned int                    m_nPriority;  // thread priority in "wx" units
+};
+
+ULONG wxThreadInternal::OS2ThreadStart(
+  wxThread*                         pThread
+)
+{
+    m_pThread = pThread;
+
+    DWORD                           dwRet = (DWORD)pThread->Entry();
+
+    pThread->p_internal->SetState(STATE_EXITED);
+    pThread->OnExit();
+
+    delete pThread;
+    m_pThread = NULL;
+    return dwRet;
+}
+
+bool wxThreadInternal::Create(
+  wxThread*                         pThread
+)
+{
+    APIRET                          ulrc;
+
+    ulrc = ::DosCreateThread( &m_hThread
+                             ,(PFNTHREAD)wxThreadInternal::OS2ThreadStart
+                             ,(ULONG)pThread
+                             ,CREATE_SUSPENDED | STACK_SPARSE
+                             ,8192L
+                            );
+    if(ulrc != 0)
+    {
+        wxLogSysError(_("Can't create thread"));
+
+        return FALSE;
+    }
+
+    // translate wxWindows priority to the PM one
+    ULONG                           ulOS2_Priority;
+
+    if (m_nPriority <= 20)
+        ulOS2_Priority = PRTYC_NOCHANGE;
+    else if (m_nPriority <= 40)
+        ulOS2_Priority = PRTYC_IDLETIME;
+    else if (m_nPriority <= 60)
+        ulOS2_Priority = PRTYC_REGULAR;
+    else if (m_nPriority <= 80)
+        ulOS2_Priority = PRTYC_TIMECRITICAL;
+    else if (m_nPriority <= 100)
+        ulOS2_Priority = PRTYC_FOREGROUNDSERVER;
+    else
+    {
+        wxFAIL_MSG(wxT("invalid value of thread priority parameter"));
+        ulOS2_Priority = PRTYC_REGULAR;
+    }
+    ulrc = ::DosSetPriority( PRTYS_THREAD
+                            ,ulOS2_Priority
+                            ,0
+                            ,(ULONG)m_hThread
+                           );
+    if (ulrc != 0)
+    {
+        wxLogSysError(_("Can't set thread priority"));
+    }
+    return TRUE;
+}
+
+bool wxThreadInternal::Suspend()
+{
+    ULONG                           ulrc = ::DosSuspendThread(m_hThread);
+
+    if (ulrc != 0)
+    {
+        wxLogSysError(_("Can not suspend thread %lu"), m_hThread);
+        return FALSE;
+    }
+    m_eState = STATE_PAUSED;
+    return TRUE;
+}
+
+bool wxThreadInternal::Resume()
+{
+    ULONG                           ulrc = ::DosResumeThread(m_hThread);
+
+    if (ulrc != 0)
+    {
+        wxLogSysError(_("Can not suspend thread %lu"), m_hThread);
+        return FALSE;
+    }
+    m_eState = STATE_PAUSED;
+    return TRUE;
+}
+
+// static functions
+// ----------------
+
+wxThread *wxThread::This()
+{
+    wxThread*                       pThread = m_pThread;
+    return pThread;
+}
+
+bool wxThread::IsMain()
+{
+    PTIB                            ptib;
+    PPIB                            ppib;
+
+    ::DosGetInfoBlocks(&ptib, &ppib);
+
+    if (ptib->tib_ptib2->tib2_ultid == s_ulIdMainThread)
+        return TRUE;
+    return FALSE;
+}
+
+#ifdef Yield
+    #undef Yield
+#endif
+
+void wxThread::Yield()
+{
+    ::DosSleep(0);
+}
+
+void wxThread::Sleep(
+  unsigned long                     ulMilliseconds
+)
+{
+    ::DosSleep(ulMilliseconds);
+}
+
+// create/start thread
+// -------------------
+

 wxThreadError wxThread::Create()
 {
 wxThreadError wxThread::Create()
 {

-    // TODO
+    if ( !p_internal->Create(this) )
+        return wxTHREAD_NO_RESOURCE;
+

     return wxTHREAD_NO_ERROR;
 }
 
     return wxTHREAD_NO_ERROR;
 }
 

-wxThreadError wxThread::Destroy()
+wxThreadError wxThread::Run()

 {
 {

-    // TODO
-    return wxTHREAD_NO_ERROR;
+    wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
+
+    if ( p_internal->GetState() != STATE_NEW )
+    {
+        // actually, it may be almost any state at all, not only STATE_RUNNING
+        return wxTHREAD_RUNNING;
+    }
+    return Resume();

 }
 
 }
 

+// suspend/resume thread
+// ---------------------
+

 wxThreadError wxThread::Pause()
 {
 wxThreadError wxThread::Pause()
 {

-    // TODO
-    return wxTHREAD_NO_ERROR;
+    wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
+
+    return p_internal->Suspend() ? wxTHREAD_NO_ERROR : wxTHREAD_MISC_ERROR;

 }
 
 wxThreadError wxThread::Resume()
 {
 }
 
 wxThreadError wxThread::Resume()
 {

-    // TODO
-    return wxTHREAD_NO_ERROR;
-}
+    wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);

 
 

-void wxThread::Exit(void *status)
-{
-    // TODO
+    return p_internal->Resume() ? wxTHREAD_NO_ERROR : wxTHREAD_MISC_ERROR;

 }
 
 }
 

-void wxThread::SetPriority(int prio)
+// stopping thread
+// ---------------
+
+wxThread::ExitCode wxThread::Delete()

 {
 {

-    // TODO
+    ExitCode                        rc = 0;
+    ULONG                           ulrc;
+
+    // Delete() is always safe to call, so consider all possible states
+    if (IsPaused())
+        Resume();
+
+    if (IsRunning())
+    {
+        if (IsMain())
+        {
+            // set flag for wxIsWaitingForThread()
+            s_bWaitingForThread = TRUE;
+            wxBeginBusyCursor();
+        }
+
+        TID                         hThread;
+
+        {
+            wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
+
+            p_internal->Cancel();
+            hThread = p_internal->GetHandle();
+        }
+
+        // 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
+
+        do
+        {
+            ulrc = ::DosWaitThread( &hThread
+                                   ,DCWW_NOWAIT
+                                  );
+            switch (ulrc)
+            {
+                case ERROR_INTERRUPT:
+                case ERROR_INVALID_THREADID:
+                    // error
+                    wxLogSysError(_("Can not wait for thread termination"));
+                    Kill();
+                    return (ExitCode)-1;
+
+                case 0:
+                    // thread we're waiting for terminated
+                    break;
+
+                case ERROR_THREAD_NOT_TERMINATED:
+                    // new message arrived, process it
+                    if (!wxTheApp->DoMessage())
+                    {
+                        // WM_QUIT received: kill the thread
+                        Kill();
+                        return (ExitCode)-1;
+                    }
+                    if (IsMain())
+                    {
+                        // give the thread we're waiting for chance to exit
+                        // from the GUI call it might have been in
+                        if ((s_nWaitingForGui > 0) && wxGuiOwnedByMainThread())
+                        {
+                            wxMutexGuiLeave();
+                        }
+                    }
+                    break;
+
+                default:
+                    wxFAIL_MSG(wxT("unexpected result of DosWatiThread"));
+            }
+        } while (ulrc != 0);
+
+        if (IsMain())
+        {
+            s_bWaitingForThread = FALSE;
+            wxEndBusyCursor();
+        }
+
+        ::DosExit(EXIT_THREAD, ulrc);
+    }
+    rc = (ExitCode)ulrc;
+    return rc;

 }
 
 }
 

-int wxThread::GetPriority() const
+wxThreadError wxThread::Kill()

 {
 {

-    // TODO
-    return 0;
+    if (!IsRunning())
+        return wxTHREAD_NOT_RUNNING;
+
+    ::DosKillThread(p_internal->GetHandle());
+    delete this;
+    return wxTHREAD_NO_ERROR;

 }
 
 }
 

-void wxThread::DeferDestroy(bool on)
+void wxThread::Exit(
+  void*                             pStatus
+)

 {
 {

-    // TODO
+    delete this;
+    ::DosExit(EXIT_THREAD, ULONG(pStatus));
+    wxFAIL_MSG(wxT("Couldn't return from DosExit()!"));

 }
 
 }
 

-void wxThread::TestDestroy()
+void wxThread::SetPriority(
+  unsigned int                      nPrio
+)

 {
 {

-    // TODO
+    wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
+
+    p_internal->SetPriority(nPrio);

 }
 
 }
 

-void *wxThread::Join()
+unsigned int wxThread::GetPriority() const

 {
 {

-    // TODO
-    return (void*) NULL;
+    wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
+
+    return p_internal->GetPriority();

 }
 
 unsigned long wxThread::GetID() const
 {
 }
 
 unsigned long wxThread::GetID() const
 {

-    // TODO
-    return 0;
+    wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
+
+    return (unsigned long)p_internal->GetId();

 }
 
 }
 

-/*
-wxThread *wxThread::GetThreadFromID(unsigned long id)
+bool wxThread::IsRunning() const

 {
 {

-    // TODO
-    return NULL;
+    wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
+
+    return p_internal->GetState() == STATE_RUNNING;

 }
 }

-*/

 
 bool wxThread::IsAlive() const
 {
 
 bool wxThread::IsAlive() const
 {

-    // TODO
-    return FALSE;
+    wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
+
+    return (p_internal->GetState() == STATE_RUNNING) ||
+           (p_internal->GetState() == STATE_PAUSED);

 }
 
 }
 

-bool wxThread::IsRunning() const
+bool wxThread::IsPaused() const

 {
 {

-    // TODO
-    return FALSE;
+    wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
+
+    return (p_internal->GetState() == STATE_PAUSED);

 }
 
 }
 

-bool wxThread::IsMain()
+bool wxThread::TestDestroy()

 {
 {

-    // TODO
-    return FALSE;
+    wxCriticalSectionLocker         lock((wxCriticalSection &)m_critsect);
+
+    return p_internal->GetState() == STATE_CANCELED;

 }
 
 wxThread::wxThread()
 {
     p_internal = new wxThreadInternal();
 }
 
 wxThread::wxThread()
 {
     p_internal = new wxThreadInternal();

-
-    // TODO

 }
 
 wxThread::~wxThread()
 {
 }
 
 wxThread::~wxThread()
 {

-    Destroy();
-    Join();

     delete p_internal;
 }
 
     delete p_internal;
 }
 

-// The default callback just joins the thread and throws away the result.
-void wxThread::OnExit()
-{
-    Join();
-}
+// ----------------------------------------------------------------------------
+// Automatic initialization for thread module
+// ----------------------------------------------------------------------------

 
 

-// Automatic initialization
-class wxThreadModule : public wxModule {
-  DECLARE_DYNAMIC_CLASS(wxThreadModule)
+class wxThreadModule : public wxModule
+{

 public:
 public:

-  virtual bool OnInit() {
-    /* TODO p_mainid = GetCurrentThread(); */
-    wxMainMutex = new wxMutex();
-    wxMainMutex->Lock();
-    return TRUE;
-  }
+    virtual bool OnInit();
+    virtual void OnExit();

 
 

-  // Global cleanup
-  virtual void OnExit() {
-    wxMainMutex->Unlock();
-    delete wxMainMutex;
-  }
+private:
+    DECLARE_DYNAMIC_CLASS(wxThreadModule)

 };
 
 IMPLEMENT_DYNAMIC_CLASS(wxThreadModule, wxModule)
 
 };
 
 IMPLEMENT_DYNAMIC_CLASS(wxThreadModule, wxModule)
 

+bool wxThreadModule::OnInit()
+{
+    s_pCritsectWaitingForGui = new wxCriticalSection();
+
+    s_pCritsectGui = new wxCriticalSection();
+    s_pCritsectGui->Enter();
+
+    PTIB                            ptib;
+    PPIB                            ppib;
+
+    ::DosGetInfoBlocks(&ptib, &ppib);
+
+    s_ulIdMainThread = ptib->tib_ptib2->tib2_ultid;
+    return TRUE;
+}
+
+void wxThreadModule::OnExit()
+{
+    if (s_pCritsectGui)
+    {
+        s_pCritsectGui->Leave();
+        delete s_pCritsectGui;
+        s_pCritsectGui = NULL;
+    }
+
+    wxDELETE(s_pCritsectWaitingForGui);
+}
+
+// ----------------------------------------------------------------------------
+// Helper functions
+// ----------------------------------------------------------------------------
+
+// Does nothing under OS/2 [for now]
+void WXDLLEXPORT wxWakeUpMainThread()
+{
+}
+
+void WXDLLEXPORT wxMutexGuiLeave()
+{
+    wxCriticalSectionLocker enter(*s_pCritsectWaitingForGui);
+
+    if ( wxThread::IsMain() )
+    {
+        s_bGuiOwnedByMainThread = FALSE;
+    }
+    else
+    {
+        // decrement the number of waiters now
+        wxASSERT_MSG( s_nWaitingForGui > 0,
+                      wxT("calling wxMutexGuiLeave() without entering it first?") );
+
+        s_nWaitingForGui--;
+
+        wxWakeUpMainThread();
+    }
+
+    s_pCritsectGui->Leave();
+}
+
+void WXDLLEXPORT wxMutexGuiLeaveOrEnter()
+{
+    wxASSERT_MSG( wxThread::IsMain(),
+                  wxT("only main thread may call wxMutexGuiLeaveOrEnter()!") );
+
+    wxCriticalSectionLocker enter(*s_pCritsectWaitingForGui);
+
+    if ( s_nWaitingForGui == 0 )
+    {
+        // no threads are waiting for GUI - so we may acquire the lock without
+        // any danger (but only if we don't already have it)
+        if (!wxGuiOwnedByMainThread())
+        {
+            s_pCritsectGui->Enter();
+
+            s_bGuiOwnedByMainThread = TRUE;
+        }
+        //else: already have it, nothing to do
+    }
+    else
+    {
+        // some threads are waiting, release the GUI lock if we have it
+        if (wxGuiOwnedByMainThread())
+        {
+            wxMutexGuiLeave();
+        }
+        //else: some other worker thread is doing GUI
+    }
+}
+
+bool WXDLLEXPORT wxGuiOwnedByMainThread()
+{
+    return s_bGuiOwnedByMainThread;
+}
+

 #endif
   // wxUSE_THREADS
 #endif
   // wxUSE_THREADS