/[dtapublic]/projs/trunk/shared_source/tcl_base/tclwinnotify.c
ViewVC logotype

Annotation of /projs/trunk/shared_source/tcl_base/tclwinnotify.c

Parent Directory Parent Directory | Revision Log Revision Log


Revision 25 - (hide annotations) (download)
Sat Oct 8 06:43:03 2016 UTC (7 years, 9 months ago) by dashley
Original Path: sf_code/esrgpcpj/shared/tcl_base/tclwinnotify.c
File MIME type: text/plain
File size: 13794 byte(s)
Initial commit.
1 dashley 25 /* $Header: /cvsroot/esrg/sfesrg/esrgpcpj/shared/tcl_base/tclwinnotify.c,v 1.1.1.1 2001/06/13 04:49:27 dtashley Exp $ */
2    
3     /*
4     * tclWinNotify.c --
5     *
6     * This file contains Windows-specific procedures for the notifier,
7     * which is the lowest-level part of the Tcl event loop. This file
8     * works together with ../generic/tclNotify.c.
9     *
10     * Copyright (c) 1995-1997 Sun Microsystems, Inc.
11     *
12     * See the file "license.terms" for information on usage and redistribution
13     * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
14     *
15     * RCS: @(#) $Id: tclwinnotify.c,v 1.1.1.1 2001/06/13 04:49:27 dtashley Exp $
16     */
17    
18     #include "tclWinInt.h"
19     #include <winsock.h>
20    
21     /*
22     * The follwing static indicates whether this module has been initialized.
23     */
24    
25     static int initialized = 0;
26    
27     #define INTERVAL_TIMER 1 /* Handle of interval timer. */
28    
29     #define WM_WAKEUP WM_USER /* Message that is send by
30     * Tcl_AlertNotifier. */
31     /*
32     * The following static structure contains the state information for the
33     * Windows implementation of the Tcl notifier. One of these structures
34     * is created for each thread that is using the notifier.
35     */
36    
37     typedef struct ThreadSpecificData {
38     CRITICAL_SECTION crit; /* Monitor for this notifier. */
39     DWORD thread; /* Identifier for thread associated with this
40     * notifier. */
41     HANDLE event; /* Event object used to wake up the notifier
42     * thread. */
43     int pending; /* Alert message pending, this field is
44     * locked by the notifierMutex. */
45     HWND hwnd; /* Messaging window. */
46     int timeout; /* Current timeout value. */
47     int timerActive; /* 1 if interval timer is running. */
48     } ThreadSpecificData;
49    
50     static Tcl_ThreadDataKey dataKey;
51    
52     extern TclStubs tclStubs;
53     /*
54     * The following static indicates the number of threads that have
55     * initialized notifiers. It controls the lifetime of the TclNotifier
56     * window class.
57     *
58     * You must hold the notifierMutex lock before accessing this variable.
59     */
60    
61     static int notifierCount = 0;
62     TCL_DECLARE_MUTEX(notifierMutex)
63    
64     /*
65     * Static routines defined in this file.
66     */
67    
68     static LRESULT CALLBACK NotifierProc(HWND hwnd, UINT message,
69     WPARAM wParam, LPARAM lParam);
70    
71    
72     /*
73     *----------------------------------------------------------------------
74     *
75     * Tcl_InitNotifier --
76     *
77     * Initializes the platform specific notifier state.
78     *
79     * Results:
80     * Returns a handle to the notifier state for this thread..
81     *
82     * Side effects:
83     * None.
84     *
85     *----------------------------------------------------------------------
86     */
87    
88     ClientData
89     Tcl_InitNotifier()
90     {
91     ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
92     WNDCLASS class;
93    
94     /*
95     * Register Notifier window class if this is the first thread to
96     * use this module.
97     */
98    
99     Tcl_MutexLock(&notifierMutex);
100     if (notifierCount == 0) {
101     class.style = 0;
102     class.cbClsExtra = 0;
103     class.cbWndExtra = 0;
104     class.hInstance = TclWinGetTclInstance();
105     class.hbrBackground = NULL;
106     class.lpszMenuName = NULL;
107     class.lpszClassName = "TclNotifier";
108     class.lpfnWndProc = NotifierProc;
109     class.hIcon = NULL;
110     class.hCursor = NULL;
111    
112     if (!RegisterClassA(&class)) {
113     panic("Unable to register TclNotifier window class");
114     }
115     }
116     notifierCount++;
117     Tcl_MutexUnlock(&notifierMutex);
118    
119     tsdPtr->pending = 0;
120     tsdPtr->timerActive = 0;
121    
122     InitializeCriticalSection(&tsdPtr->crit);
123    
124     tsdPtr->hwnd = NULL;
125     tsdPtr->thread = GetCurrentThreadId();
126     tsdPtr->event = CreateEvent(NULL, TRUE /* manual */,
127     FALSE /* !signaled */, NULL);
128    
129     return (ClientData) tsdPtr;
130     }
131    
132     /*
133     *----------------------------------------------------------------------
134     *
135     * Tcl_FinalizeNotifier --
136     *
137     * This function is called to cleanup the notifier state before
138     * a thread is terminated.
139     *
140     * Results:
141     * None.
142     *
143     * Side effects:
144     * May dispose of the notifier window and class.
145     *
146     *----------------------------------------------------------------------
147     */
148    
149     void
150     Tcl_FinalizeNotifier(clientData)
151     ClientData clientData; /* Pointer to notifier data. */
152     {
153     ThreadSpecificData *tsdPtr = (ThreadSpecificData *) clientData;
154    
155     DeleteCriticalSection(&tsdPtr->crit);
156     CloseHandle(tsdPtr->event);
157    
158     /*
159     * Clean up the timer and messaging window for this thread.
160     */
161    
162     if (tsdPtr->hwnd) {
163     KillTimer(tsdPtr->hwnd, INTERVAL_TIMER);
164     DestroyWindow(tsdPtr->hwnd);
165     }
166    
167     /*
168     * If this is the last thread to use the notifier, unregister
169     * the notifier window class.
170     */
171    
172     Tcl_MutexLock(&notifierMutex);
173     notifierCount--;
174     if (notifierCount == 0) {
175     UnregisterClassA("TclNotifier", TclWinGetTclInstance());
176     }
177     Tcl_MutexUnlock(&notifierMutex);
178     }
179    
180     /*
181     *----------------------------------------------------------------------
182     *
183     * Tcl_AlertNotifier --
184     *
185     * Wake up the specified notifier from any thread. This routine
186     * is called by the platform independent notifier code whenever
187     * the Tcl_ThreadAlert routine is called. This routine is
188     * guaranteed not to be called on a given notifier after
189     * Tcl_FinalizeNotifier is called for that notifier. This routine
190     * is typically called from a thread other than the notifier's
191     * thread.
192     *
193     * Results:
194     * None.
195     *
196     * Side effects:
197     * Sends a message to the messaging window for the notifier
198     * if there isn't already one pending.
199     *
200     *----------------------------------------------------------------------
201     */
202    
203     void
204     Tcl_AlertNotifier(clientData)
205     ClientData clientData; /* Pointer to thread data. */
206     {
207     ThreadSpecificData *tsdPtr = (ThreadSpecificData *) clientData;
208    
209     /*
210     * Note that we do not need to lock around access to the hwnd
211     * because the race condition has no effect since any race condition
212     * implies that the notifier thread is already awake.
213     */
214    
215     if (tsdPtr->hwnd) {
216     /*
217     * We do need to lock around access to the pending flag.
218     */
219    
220     EnterCriticalSection(&tsdPtr->crit);
221     if (!tsdPtr->pending) {
222     PostMessage(tsdPtr->hwnd, WM_WAKEUP, 0, 0);
223     }
224     tsdPtr->pending = 1;
225     LeaveCriticalSection(&tsdPtr->crit);
226     } else {
227     SetEvent(tsdPtr->event);
228     }
229     }
230    
231     /*
232     *----------------------------------------------------------------------
233     *
234     * Tcl_SetTimer --
235     *
236     * This procedure sets the current notifier timer value. The
237     * notifier will ensure that Tcl_ServiceAll() is called after
238     * the specified interval, even if no events have occurred.
239     *
240     * Results:
241     * None.
242     *
243     * Side effects:
244     * Replaces any previous timer.
245     *
246     *----------------------------------------------------------------------
247     */
248    
249     void
250     Tcl_SetTimer(
251     Tcl_Time *timePtr) /* Maximum block time, or NULL. */
252     {
253     ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
254     UINT timeout;
255    
256     /*
257     * Allow the notifier to be hooked. This may not make sense
258     * on Windows, but mirrors the UNIX hook.
259     */
260    
261     if (tclStubs.tcl_SetTimer != Tcl_SetTimer) {
262     tclStubs.tcl_SetTimer(timePtr);
263     return;
264     }
265    
266     /*
267     * We only need to set up an interval timer if we're being called
268     * from an external event loop. If we don't have a window handle
269     * then we just return immediately and let Tcl_WaitForEvent handle
270     * timeouts.
271     */
272    
273     if (!tsdPtr->hwnd) {
274     return;
275     }
276    
277     if (!timePtr) {
278     timeout = 0;
279     } else {
280     /*
281     * Make sure we pass a non-zero value into the timeout argument.
282     * Windows seems to get confused by zero length timers.
283     */
284    
285     timeout = timePtr->sec * 1000 + timePtr->usec / 1000;
286     if (timeout == 0) {
287     timeout = 1;
288     }
289     }
290     tsdPtr->timeout = timeout;
291     if (timeout != 0) {
292     tsdPtr->timerActive = 1;
293     SetTimer(tsdPtr->hwnd, INTERVAL_TIMER,
294     (unsigned long) tsdPtr->timeout, NULL);
295     } else {
296     tsdPtr->timerActive = 0;
297     KillTimer(tsdPtr->hwnd, INTERVAL_TIMER);
298     }
299     }
300    
301     /*
302     *----------------------------------------------------------------------
303     *
304     * Tcl_ServiceModeHook --
305     *
306     * This function is invoked whenever the service mode changes.
307     *
308     * Results:
309     * None.
310     *
311     * Side effects:
312     * If this is the first time the notifier is set into
313     * TCL_SERVICE_ALL, then the communication window is created.
314     *
315     *----------------------------------------------------------------------
316     */
317    
318     void
319     Tcl_ServiceModeHook(mode)
320     int mode; /* Either TCL_SERVICE_ALL, or
321     * TCL_SERVICE_NONE. */
322     {
323     ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
324    
325     /*
326     * If this is the first time that the notifier has been used from a
327     * modal loop, then create a communication window. Note that after
328     * this point, the application needs to service events in a timely
329     * fashion or Windows will hang waiting for the window to respond
330     * to synchronous system messages. At some point, we may want to
331     * consider destroying the window if we leave the modal loop, but
332     * for now we'll leave it around.
333     */
334    
335     if (mode == TCL_SERVICE_ALL && !tsdPtr->hwnd) {
336     tsdPtr->hwnd = CreateWindowA("TclNotifier", "TclNotifier", WS_TILED,
337     0, 0, 0, 0, NULL, NULL, TclWinGetTclInstance(), NULL);
338     /*
339     * Send an initial message to the window to ensure that we wake up the
340     * notifier once we get into the modal loop. This will force the
341     * notifier to recompute the timeout value and schedule a timer
342     * if one is needed.
343     */
344    
345     Tcl_AlertNotifier((ClientData)tsdPtr);
346     }
347     }
348    
349     /*
350     *----------------------------------------------------------------------
351     *
352     * NotifierProc --
353     *
354     * This procedure is invoked by Windows to process events on
355     * the notifier window. Messages will be sent to this window
356     * in response to external timer events or calls to
357     * TclpAlertTsdPtr->
358     *
359     * Results:
360     * A standard windows result.
361     *
362     * Side effects:
363     * Services any pending events.
364     *
365     *----------------------------------------------------------------------
366     */
367    
368     static LRESULT CALLBACK
369     NotifierProc(
370     HWND hwnd,
371     UINT message,
372     WPARAM wParam,
373     LPARAM lParam)
374     {
375     ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
376    
377     if (message == WM_WAKEUP) {
378     EnterCriticalSection(&tsdPtr->crit);
379     tsdPtr->pending = 0;
380     LeaveCriticalSection(&tsdPtr->crit);
381     } else if (message != WM_TIMER) {
382     return DefWindowProc(hwnd, message, wParam, lParam);
383     }
384    
385     /*
386     * Process all of the runnable events.
387     */
388    
389     Tcl_ServiceAll();
390     return 0;
391     }
392    
393     /*
394     *----------------------------------------------------------------------
395     *
396     * Tcl_WaitForEvent --
397     *
398     * This function is called by Tcl_DoOneEvent to wait for new
399     * events on the message queue. If the block time is 0, then
400     * Tcl_WaitForEvent just polls the event queue without blocking.
401     *
402     * Results:
403     * Returns -1 if a WM_QUIT message is detected, returns 1 if
404     * a message was dispatched, otherwise returns 0.
405     *
406     * Side effects:
407     * Dispatches a message to a window procedure, which could do
408     * anything.
409     *
410     *----------------------------------------------------------------------
411     */
412    
413     int
414     Tcl_WaitForEvent(
415     Tcl_Time *timePtr) /* Maximum block time, or NULL. */
416     {
417     ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
418     MSG msg;
419     DWORD timeout, result;
420     int status;
421    
422     /*
423     * Allow the notifier to be hooked. This may not make
424     * sense on windows, but mirrors the UNIX hook.
425     */
426    
427     if (tclStubs.tcl_WaitForEvent != Tcl_WaitForEvent) {
428     return tclStubs.tcl_WaitForEvent(timePtr);
429     }
430    
431     /*
432     * Compute the timeout in milliseconds.
433     */
434    
435     if (timePtr) {
436     timeout = timePtr->sec * 1000 + timePtr->usec / 1000;
437     } else {
438     timeout = INFINITE;
439     }
440    
441     /*
442     * Check to see if there are any messages in the queue before waiting
443     * because MsgWaitForMultipleObjects will not wake up if there are events
444     * currently sitting in the queue.
445     */
446    
447     if (!PeekMessage(&msg, NULL, 0, 0, PM_NOREMOVE)) {
448     /*
449     * Wait for something to happen (a signal from another thread, a
450     * message, or timeout).
451     */
452    
453     result = MsgWaitForMultipleObjects(1, &tsdPtr->event, FALSE, timeout,
454     QS_ALLINPUT);
455     }
456    
457     /*
458     * Check to see if there are any messages to process.
459     */
460    
461     if (PeekMessage(&msg, NULL, 0, 0, PM_NOREMOVE)) {
462     /*
463     * Retrieve and dispatch the first message.
464     */
465    
466     result = GetMessage(&msg, NULL, 0, 0);
467     if (result == 0) {
468     /*
469     * We received a request to exit this thread (WM_QUIT), so
470     * propagate the quit message and start unwinding.
471     */
472    
473     PostQuitMessage(msg.wParam);
474     status = -1;
475     } else if (result == -1) {
476     /*
477     * We got an error from the system. I have no idea why this would
478     * happen, so we'll just unwind.
479     */
480    
481     status = -1;
482     } else {
483     TranslateMessage(&msg);
484     DispatchMessage(&msg);
485     status = 1;
486     }
487     } else {
488     status = 0;
489     }
490    
491     ResetEvent(tsdPtr->event);
492     return status;
493     }
494    
495     /*
496     *----------------------------------------------------------------------
497     *
498     * Tcl_Sleep --
499     *
500     * Delay execution for the specified number of milliseconds.
501     *
502     * Results:
503     * None.
504     *
505     * Side effects:
506     * Time passes.
507     *
508     *----------------------------------------------------------------------
509     */
510    
511     void
512     Tcl_Sleep(ms)
513     int ms; /* Number of milliseconds to sleep. */
514     {
515     Sleep(ms);
516     }
517    
518    
519     /* $History: tclwinnotify.c $
520     *
521     * ***************** Version 1 *****************
522     * User: Dtashley Date: 1/02/01 Time: 12:28a
523     * Created in $/IjuScripter, IjuConsole/Source/Tcl Base
524     * Initial check-in.
525     */
526    
527     /* End of TCLWINNOTIFY.C */

dashley@gmail.com
ViewVC Help
Powered by ViewVC 1.1.25