[Bug 3508771]: Cygwin notifier for handling win32 events

1 files changed, 145 insertions, 2 deletions

diff --git a/unix/tclUnixNotfy.c b/unix/tclUnixNotfy.c
index ebbbb78..c1bc430 100644
--- a/unix/tclUnixNotfy.c
+++ b/unix/tclUnixNotfy.c
@@ -91,9 +91,16 @@ typedef struct ThreadSpecificData {
 				 * from these pointers. You must hold the
 				 * notifierMutex lock before accessing these
 				 * fields. */
+#ifdef __CYGWIN__
+    void *event;     /* Any other thread alerts a notifier
+	 * that an event is ready to be processed
+	 * by sending this event. */
+    void *hwnd;			/* Messaging window. */
+#else /* !__CYGWIN__ */
     Tcl_Condition waitCV;	/* Any other thread alerts a notifier that an
 				 * event is ready to be processed by signaling
 				 * this condition variable. */
+#endif /* __CYGWIN__ */
     int eventReady;		/* True if an event is ready to be processed.
 				 * Used as condition flag together with waitCV
 				 * above. */
@@ -197,6 +204,48 @@ static int		FileHandlerEventProc(Tcl_Event *evPtr, int flags);
  *----------------------------------------------------------------------
  */
 
+#if defined(TCL_THREADS) && defined(__CYGWIN__)
+
+typedef struct {
+    void *hwnd;
+    unsigned int *message;
+    int wParam;
+    int lParam;
+    int time;
+    int x;
+    int y;
+} MSG;
+
+typedef struct {
+  unsigned int style;
+  void *lpfnWndProc;
+  int cbClsExtra;
+  int cbWndExtra;
+  void *hInstance;
+  void *hIcon;
+  void *hCursor;
+  void *hbrBackground;
+  void *lpszMenuName;
+  void *lpszClassName;
+} WNDCLASS;
+
+extern unsigned char __stdcall PeekMessageW(MSG *, void *, int, int, int);
+extern unsigned char __stdcall GetMessageW(MSG *, void *, int, int);
+extern unsigned char __stdcall TranslateMessage(const MSG *);
+extern int __stdcall DispatchMessageW(const MSG *);
+extern void __stdcall PostQuitMessage(int);
+extern void * __stdcall CreateWindowExW(void *, void *, void *, DWORD, int, int, int, int, void *, void *, void *, void *);
+extern unsigned char __stdcall DestroyWindow(void *);
+extern unsigned char __stdcall PostMessageW(void *, unsigned int, void *, void *);
+extern void *__stdcall RegisterClassW(const WNDCLASS *);
+extern DWORD __stdcall DefWindowProcW(void *, int, void *, void *);
+extern void *__stdcall CreateEventW(void *, unsigned char, unsigned char, void *);
+extern void __stdcall CloseHandle(void *);
+extern void __stdcall MsgWaitForMultipleObjects(DWORD, void *, unsigned char, DWORD, DWORD);
+extern unsigned char __stdcall ResetEvent(void *);
+
+#endif
+
 ClientData
 Tcl_InitNotifier(void)
 {
@@ -311,7 +360,11 @@ Tcl_FinalizeNotifier(
 	 * Clean up any synchronization objects in the thread local storage.
 	 */
 
-	Tcl_ConditionFinalize(&tsdPtr->waitCV);
+#ifdef __CYGWIN__
+	CloseHandle(tsdPtr->event);
+#else /* __CYGWIN__ */
+	Tcl_ConditionFinalize(&(tsdPtr->waitCV));
+#endif /* __CYGWIN__ */
 
 	Tcl_MutexUnlock(&notifierMutex);
 #endif /* TCL_THREADS */
@@ -350,7 +403,11 @@ Tcl_AlertNotifier(
 
 	Tcl_MutexLock(&notifierMutex);
 	tsdPtr->eventReady = 1;
+#ifdef __CYGWIN__
+	PostMessageW(tsdPtr->hwnd, 1024, 0, 0);
+#else
 	Tcl_ConditionNotify(&tsdPtr->waitCV);
+#endif
 	Tcl_MutexUnlock(&notifierMutex);
 #endif /* TCL_THREADS */
     }
@@ -656,6 +713,31 @@ FileHandlerEventProc(
     return 1;
 }
 
+#if defined(TCL_THREADS) && defined(__CYGWIN__)
+
+static DWORD __stdcall
+NotifierProc(
+    void *hwnd,
+    unsigned int message,
+    void *wParam,
+    void *lParam)
+{
+    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
+
+    if (message != 1024) {
+	return DefWindowProcW(hwnd, message, wParam, lParam);
+    }
+
+    /*
+     * Process all of the runnable events.
+     */
+
+	tsdPtr->eventReady = 1;
+    Tcl_ServiceAll();
+    return 0;
+}
+#endif /* __CYGWIN__ */
+
 /*
  *----------------------------------------------------------------------
  *
@@ -686,6 +768,9 @@ Tcl_WaitForEvent(
 	Tcl_Time vTime;
 #ifdef TCL_THREADS
 	int waitForFiles;
+# ifdef __CYGWIN__
+    MSG msg;
+# endif
 #else
 	/*
 	 * Impl. notes: timeout & timeoutPtr are used if, and only if threads
@@ -741,6 +826,30 @@ Tcl_WaitForEvent(
 	 * notifier thread, and wait for a response or a timeout.
 	 */
 
+#ifdef __CYGWIN__
+	if (!tsdPtr->hwnd) {
+		WNDCLASS class;
+
+	    class.style = 0;
+	    class.cbClsExtra = 0;
+	    class.cbWndExtra = 0;
+	    class.hInstance = TclWinGetTclInstance();
+	    class.hbrBackground = NULL;
+	    class.lpszMenuName = NULL;
+	    class.lpszClassName = L"TclNotifier";
+	    class.lpfnWndProc = NotifierProc;
+	    class.hIcon = NULL;
+	    class.hCursor = NULL;
+
+	    RegisterClassW(&class);
+	    tsdPtr->hwnd = CreateWindowExW(NULL, class.lpszClassName, class.lpszClassName,
+		    0, 0, 0, 0, 0, NULL, NULL, TclWinGetTclInstance(), NULL);
+	    tsdPtr->event = CreateEventW(NULL, 1 /* manual */,
+		    0 /* !signaled */, NULL);
+    }
+
+#endif
+
 	Tcl_MutexLock(&notifierMutex);
 
 	if (timePtr != NULL && timePtr->sec == 0 && (timePtr->usec == 0
@@ -797,10 +906,40 @@ Tcl_WaitForEvent(
 	FD_ZERO(&tsdPtr->readyMasks.exception);
 
 	if (!tsdPtr->eventReady) {
+#ifdef __CYGWIN__
+	    if (!PeekMessageW(&msg, NULL, 0, 0, 0)) {
+		DWORD timeout;
+		if (timePtr) {
+		    timeout = timePtr->sec * 1000 + timePtr->usec / 1000;
+		} else {
+		    timeout = 0xFFFFFFFF;
+		}
+		Tcl_MutexUnlock(&notifierMutex);
+		MsgWaitForMultipleObjects(1, &tsdPtr->event, 0, timeout, 1279);
+		Tcl_MutexLock(&notifierMutex);
+	    }
+#else
 	    Tcl_ConditionWait(&tsdPtr->waitCV, &notifierMutex, timePtr);
+#endif
 	}
 	tsdPtr->eventReady = 0;
 
+#ifdef __CYGWIN__
+	while (PeekMessageW(&msg, NULL, 0, 0, 0)) {
+	    /*
+	     * Retrieve and dispatch the message.
+	     */
+	    DWORD result = GetMessageW(&msg, NULL, 0, 0);
+	    if (result == 0) {
+		PostQuitMessage(msg.wParam);
+		/* What to do here? */
+	    } else if (result != (DWORD)-1) {
+		TranslateMessage(&msg);
+		DispatchMessageW(&msg);
+	    }
+	}
+	ResetEvent(tsdPtr->event);
+#endif
 	if (waitForFiles && tsdPtr->onList) {
 	    /*
 	     * Remove the ThreadSpecificData structure of this thread from the
@@ -1071,7 +1210,11 @@ NotifierThreadProc(
 		    tsdPtr->onList = 0;
 		    tsdPtr->pollState = 0;
 		}
-		Tcl_ConditionNotify(&tsdPtr->waitCV);
+#ifdef __CYGWIN__
+	    PostMessageW(tsdPtr->hwnd, 1024, 0, 0);
+#else /* __CYGWIN__ */
+	    Tcl_ConditionNotify(&tsdPtr->waitCV);
+#endif /* __CYGWIN__ */
 	    }
 	}
 	Tcl_MutexUnlock(&notifierMutex);