fix for using wxDataObjectComposite with the clipboard

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

diff --git a/src/msw/thread.cpp b/src/msw/thread.cpp
index e701abb39bc42521d5b8e6aee02f939872db76ea..ab8030e5840c1c0e0ed557f4ebf8783b3b465e90 100644 (file)
--- a/src/msw/thread.cpp
+++ b/src/msw/thread.cpp
@@ -45,21 +45,42 @@
     #define _MT
 #endif
 
     #define _MT
 #endif
 

+#if defined(__BORLANDC__)
+    #if !defined(__MT__)
+        // I can't set -tWM in the IDE (anyone?) so have to do this
+        #define __MT__
+    #endif
+
+    #if !defined(__MFC_COMPAT__)
+        // Needed to know about _beginthreadex etc..
+        #define __MFC_COMPAT__
+    #endif
+#endif // BC++
+
+// define wxUSE_BEGIN_THREAD if the compiler has _beginthreadex() function
+// which should be used instead of Win32 ::CreateThread() if possible

 #if defined(__VISUALC__) || \
     (defined(__BORLANDC__) && (__BORLANDC__ >= 0x500)) || \
 #if defined(__VISUALC__) || \
     (defined(__BORLANDC__) && (__BORLANDC__ >= 0x500)) || \

-    (defined(__GNUG__) && defined(__MSVCRT__))
-
-#if defined(__BORLANDC__) && !defined(__MT__)
-// I can't set -tWM in the IDE (anyone?) so have to do this
-#define __MT__
-#endif
+    (defined(__GNUG__) && defined(__MSVCRT__)) || \
+    defined(__WATCOMC__)

 
 

-#if defined(__BORLANDC__) && !defined(__MFC_COMPAT__)
-// Needed to know about _beginthreadex etc..
-#define __MFC_COMPAT__
+    #undef wxUSE_BEGIN_THREAD
+    #define wxUSE_BEGIN_THREAD

 #endif
 
 #endif
 

+#ifdef wxUSE_BEGIN_THREAD
+    // this is where _beginthreadex() is declared

     #include <process.h>
     #include <process.h>

+
+    // the return type of the thread function entry point
+    typedef unsigned THREAD_RETVAL;
+
+    // the calling convention of the thread function entry point
+    #define THREAD_CALLCONV __stdcall
+#else
+    // the settings for CreateThread()
+    typedef DWORD THREAD_RETVAL;
+    #define THREAD_CALLCONV WINAPI

 #endif
 
 // ----------------------------------------------------------------------------
 #endif
 
 // ----------------------------------------------------------------------------


@@ -211,44 +232,83 @@ class wxConditionInternal
 public:
     wxConditionInternal()
     {
 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."));
         }
         {
             wxLogSysError(_("Can not create event object."));
         }

-        waiters = 0;
+
+        // nobody waits for us yet
+        m_nWaiters = 0;

     }
 
     bool Wait(DWORD timeout)
     {
     }
 
     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;
     }
 
 
         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()
     {
     ~wxConditionInternal()
     {

-        if ( event )
+        if ( m_hEvent )

         {
         {

-            if ( !::CloseHandle(event) )
+            if ( !::CloseHandle(m_hEvent) )

             {
                 wxLogLastError(wxT("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()
 };
 
 wxCondition::wxCondition()


@@ -274,26 +334,12 @@ bool wxCondition::Wait(unsigned long sec,
 
 void wxCondition::Signal()
 {
 
 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(wxT("SetEvent"));
-    }
+    m_internal->Signal();

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

 }
 
 // ----------------------------------------------------------------------------
 }
 
 // ----------------------------------------------------------------------------


@@ -302,8 +348,14 @@ void wxCondition::Broadcast()
 
 wxCriticalSection::wxCriticalSection()
 {
 
 wxCriticalSection::wxCriticalSection()
 {

-    wxASSERT_MSG( sizeof(CRITICAL_SECTION) <= sizeof(m_buffer),
+#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") );
                   _T("must increase buffer size in wx/thread.h") );

+#endif

 
     ::InitializeCriticalSection((CRITICAL_SECTION *)m_buffer);
 }
 
     ::InitializeCriticalSection((CRITICAL_SECTION *)m_buffer);
 }


@@ -379,7 +431,7 @@ public:
     DWORD  GetId() const { return m_tid; }
 
     // thread function
     DWORD  GetId() const { return m_tid; }
 
     // thread function

-    static DWORD WinThreadStart(wxThread *thread);
+    static THREAD_RETVAL THREAD_CALLCONV WinThreadStart(void *thread);

 
 private:
     HANDLE        m_hThread;    // handle of the thread
 
 private:
     HANDLE        m_hThread;    // handle of the thread


@@ -388,16 +440,17 @@ private:
     DWORD         m_tid;        // thread id
 };
 
     DWORD         m_tid;        // thread id
 };
 

-DWORD wxThreadInternal::WinThreadStart(wxThread *thread)
+THREAD_RETVAL THREAD_CALLCONV wxThreadInternal::WinThreadStart(void *param)

 {
 {

-    DWORD rc;
+    THREAD_RETVAL rc;

     bool wasCancelled;
 
     // first of all, check whether we hadn't been cancelled already and don't
     // start the user code at all then
     bool wasCancelled;
 
     // first of all, check whether we hadn't been cancelled already and don't
     // start the user code at all then

+    wxThread *thread = (wxThread *)param;

     if ( thread->m_internal->GetState() == STATE_EXITED )
     {
     if ( thread->m_internal->GetState() == STATE_EXITED )
     {

-        rc = (DWORD)-1;
+        rc = (THREAD_RETVAL)-1;

         wasCancelled = TRUE;
     }
     else // do run thread
         wasCancelled = TRUE;
     }
     else // do run thread


@@ -410,7 +463,7 @@ DWORD wxThreadInternal::WinThreadStart(wxThread *thread)
             return (DWORD)-1;
         }
 
             return (DWORD)-1;
         }
 

-        rc = (DWORD)thread->Entry();
+        rc = (THREAD_RETVAL)thread->Entry();

 
         // enter m_critsect before changing the thread state
         thread->m_critsect.Enter();
 
         // enter m_critsect before changing the thread state
         thread->m_critsect.Enter();


@@ -466,23 +519,26 @@ bool wxThreadInternal::Create(wxThread *thread)
     // for compilers which have it, we should use C RTL function for thread
     // creation instead of Win32 API one because otherwise we will have memory
     // leaks if the thread uses C RTL (and most threads do)
     // for compilers which have it, we should use C RTL function for thread
     // creation instead of Win32 API one because otherwise we will have memory
     // leaks if the thread uses C RTL (and most threads do)

-#if defined(__VISUALC__) || \
-    (defined(__BORLANDC__) && (__BORLANDC__ >= 0x500)) || \
-    (defined(__GNUG__) && defined(__MSVCRT__))
-    typedef unsigned (__stdcall *RtlThreadStart)(void *);
-
-    m_hThread = (HANDLE)_beginthreadex(NULL, 0,
-                                       (RtlThreadStart)
-                                       wxThreadInternal::WinThreadStart,
-                                       thread, CREATE_SUSPENDED,
-                                       (unsigned int *)&m_tid);
+#ifdef wxUSE_BEGIN_THREAD
+    m_hThread = (HANDLE)_beginthreadex
+                        (
+                            NULL,   // default security
+#ifdef __WATCOMC__
+                            10240,  // stack size can't be NULL in Watcom
+#else
+                            0,      // default stack size
+#endif
+                            wxThreadInternal::WinThreadStart, // entry point
+                            thread,
+                            CREATE_SUSPENDED,
+                            (unsigned int *)&m_tid
+                        );

 #else // compiler doesn't have _beginthreadex
     m_hThread = ::CreateThread
                   (
                     NULL,                               // default security
                     0,                                  // default stack size
 #else // compiler doesn't have _beginthreadex
     m_hThread = ::CreateThread
                   (
                     NULL,                               // default security
                     0,                                  // default stack size

-                    (LPTHREAD_START_ROUTINE)            // thread entry point
-                    wxThreadInternal::WinThreadStart,   //
+                    wxThreadInternal::WinThreadStart,   // thread entry point

                     (LPVOID)thread,                     // parameter
                     CREATE_SUSPENDED,                   // flags
                     &m_tid                              // [out] thread id
                     (LPVOID)thread,                     // parameter
                     CREATE_SUSPENDED,                   // flags
                     &m_tid                              // [out] thread id


@@ -954,9 +1010,7 @@ void wxThread::Exit(ExitCode status)
         delete this;
     }
 
         delete this;
     }
 

-#if defined(__VISUALC__) || \
-    (defined(__BORLANDC__) && (__BORLANDC__ >= 0x500)) || \
-    (defined(__GNUG__) && defined(__MSVCRT__))
+#ifdef wxUSE_BEGIN_THREAD

     _endthreadex((unsigned)status);
 #else // !VC++
     ::ExitThread((DWORD)status);
     _endthreadex((unsigned)status);
 #else // !VC++
     ::ExitThread((DWORD)status);


@@ -1126,7 +1180,7 @@ void WXDLLEXPORT wxMutexGuiLeave()
     }
     else
     {
     }
     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?") );
 
         wxASSERT_MSG( gs_nWaitingForGui > 0,
                       wxT("calling wxMutexGuiLeave() without entering it first?") );