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Diffstat (limited to 'generic/tkEvent.c')
| -rw-r--r-- | generic/tkEvent.c | 1038 |
1 files changed, 1038 insertions, 0 deletions
diff --git a/generic/tkEvent.c b/generic/tkEvent.c new file mode 100644 index 0000000..045a478 --- /dev/null +++ b/generic/tkEvent.c @@ -0,0 +1,1038 @@ +/* + * tkEvent.c -- + * + * This file provides basic low-level facilities for managing + * X events in Tk. + * + * Copyright (c) 1990-1994 The Regents of the University of California. + * Copyright (c) 1994-1995 Sun Microsystems, Inc. + * + * See the file "license.terms" for information on usage and redistribution + * of this file, and for a DISCLAIMER OF ALL WARRANTIES. + * + * SCCS: @(#) tkEvent.c 1.20 96/09/20 09:33:38 + */ + +#include "tkPort.h" +#include "tkInt.h" +#include <signal.h> + +/* + * There's a potential problem if a handler is deleted while it's + * current (i.e. its procedure is executing), since Tk_HandleEvent + * will need to read the handler's "nextPtr" field when the procedure + * returns. To handle this problem, structures of the type below + * indicate the next handler to be processed for any (recursively + * nested) dispatches in progress. The nextHandler fields get + * updated if the handlers pointed to are deleted. Tk_HandleEvent + * also needs to know if the entire window gets deleted; the winPtr + * field is set to zero if that particular window gets deleted. + */ + +typedef struct InProgress { + XEvent *eventPtr; /* Event currently being handled. */ + TkWindow *winPtr; /* Window for event. Gets set to None if + * window is deleted while event is being + * handled. */ + TkEventHandler *nextHandler; /* Next handler in search. */ + struct InProgress *nextPtr; /* Next higher nested search. */ +} InProgress; + +static InProgress *pendingPtr = NULL; + /* Topmost search in progress, or + * NULL if none. */ + +/* + * For each call to Tk_CreateGenericHandler, an instance of the following + * structure will be created. All of the active handlers are linked into a + * list. + */ + +typedef struct GenericHandler { + Tk_GenericProc *proc; /* Procedure to dispatch on all X events. */ + ClientData clientData; /* Client data to pass to procedure. */ + int deleteFlag; /* Flag to set when this handler is deleted. */ + struct GenericHandler *nextPtr; + /* Next handler in list of all generic + * handlers, or NULL for end of list. */ +} GenericHandler; + +static GenericHandler *genericList = NULL; + /* First handler in the list, or NULL. */ +static GenericHandler *lastGenericPtr = NULL; + /* Last handler in list. */ + +/* + * There's a potential problem if Tk_HandleEvent is entered recursively. + * A handler cannot be deleted physically until we have returned from + * calling it. Otherwise, we're looking at unallocated memory in advancing to + * its `next' entry. We deal with the problem by using the `delete flag' and + * deleting handlers only when it's known that there's no handler active. + * + * The following variable has a non-zero value when a handler is active. + */ + +static int genericHandlersActive = 0; + +/* + * The following structure is used for queueing X-style events on the + * Tcl event queue. + */ + +typedef struct TkWindowEvent { + Tcl_Event header; /* Standard information for all events. */ + XEvent event; /* The X event. */ +} TkWindowEvent; + +/* + * Array of event masks corresponding to each X event: + */ + +static unsigned long eventMasks[TK_LASTEVENT] = { + 0, + 0, + KeyPressMask, /* KeyPress */ + KeyReleaseMask, /* KeyRelease */ + ButtonPressMask, /* ButtonPress */ + ButtonReleaseMask, /* ButtonRelease */ + PointerMotionMask|PointerMotionHintMask|ButtonMotionMask + |Button1MotionMask|Button2MotionMask|Button3MotionMask + |Button4MotionMask|Button5MotionMask, + /* MotionNotify */ + EnterWindowMask, /* EnterNotify */ + LeaveWindowMask, /* LeaveNotify */ + FocusChangeMask, /* FocusIn */ + FocusChangeMask, /* FocusOut */ + KeymapStateMask, /* KeymapNotify */ + ExposureMask, /* Expose */ + ExposureMask, /* GraphicsExpose */ + ExposureMask, /* NoExpose */ + VisibilityChangeMask, /* VisibilityNotify */ + SubstructureNotifyMask, /* CreateNotify */ + StructureNotifyMask, /* DestroyNotify */ + StructureNotifyMask, /* UnmapNotify */ + StructureNotifyMask, /* MapNotify */ + SubstructureRedirectMask, /* MapRequest */ + StructureNotifyMask, /* ReparentNotify */ + StructureNotifyMask, /* ConfigureNotify */ + SubstructureRedirectMask, /* ConfigureRequest */ + StructureNotifyMask, /* GravityNotify */ + ResizeRedirectMask, /* ResizeRequest */ + StructureNotifyMask, /* CirculateNotify */ + SubstructureRedirectMask, /* CirculateRequest */ + PropertyChangeMask, /* PropertyNotify */ + 0, /* SelectionClear */ + 0, /* SelectionRequest */ + 0, /* SelectionNotify */ + ColormapChangeMask, /* ColormapNotify */ + 0, /* ClientMessage */ + 0, /* Mapping Notify */ + VirtualEventMask, /* VirtualEvents */ + ActivateMask, /* ActivateNotify */ + ActivateMask /* DeactivateNotify */ +}; + +/* + * If someone has called Tk_RestrictEvents, the information below + * keeps track of it. + */ + +static Tk_RestrictProc *restrictProc; + /* Procedure to call. NULL means no + * restrictProc is currently in effect. */ +static ClientData restrictArg; /* Argument to pass to restrictProc. */ + +/* + * Prototypes for procedures that are only referenced locally within + * this file. + */ + +static void DelayedMotionProc _ANSI_ARGS_((ClientData clientData)); +static int WindowEventProc _ANSI_ARGS_((Tcl_Event *evPtr, + int flags)); + +/* + *-------------------------------------------------------------- + * + * Tk_CreateEventHandler -- + * + * Arrange for a given procedure to be invoked whenever + * events from a given class occur in a given window. + * + * Results: + * None. + * + * Side effects: + * From now on, whenever an event of the type given by + * mask occurs for token and is processed by Tk_HandleEvent, + * proc will be called. See the manual entry for details + * of the calling sequence and return value for proc. + * + *-------------------------------------------------------------- + */ + +void +Tk_CreateEventHandler(token, mask, proc, clientData) + Tk_Window token; /* Token for window in which to + * create handler. */ + unsigned long mask; /* Events for which proc should + * be called. */ + Tk_EventProc *proc; /* Procedure to call for each + * selected event */ + ClientData clientData; /* Arbitrary data to pass to proc. */ +{ + register TkEventHandler *handlerPtr; + register TkWindow *winPtr = (TkWindow *) token; + int found; + + /* + * Skim through the list of existing handlers to (a) compute the + * overall event mask for the window (so we can pass this new + * value to the X system) and (b) see if there's already a handler + * declared with the same callback and clientData (if so, just + * change the mask). If no existing handler matches, then create + * a new handler. + */ + + found = 0; + if (winPtr->handlerList == NULL) { + handlerPtr = (TkEventHandler *) ckalloc( + (unsigned) sizeof(TkEventHandler)); + winPtr->handlerList = handlerPtr; + goto initHandler; + } else { + for (handlerPtr = winPtr->handlerList; ; + handlerPtr = handlerPtr->nextPtr) { + if ((handlerPtr->proc == proc) + && (handlerPtr->clientData == clientData)) { + handlerPtr->mask = mask; + found = 1; + } + if (handlerPtr->nextPtr == NULL) { + break; + } + } + } + + /* + * Create a new handler if no matching old handler was found. + */ + + if (!found) { + handlerPtr->nextPtr = (TkEventHandler *) + ckalloc(sizeof(TkEventHandler)); + handlerPtr = handlerPtr->nextPtr; + initHandler: + handlerPtr->mask = mask; + handlerPtr->proc = proc; + handlerPtr->clientData = clientData; + handlerPtr->nextPtr = NULL; + } + + /* + * No need to call XSelectInput: Tk always selects on all events + * for all windows (needed to support bindings on classes and "all"). + */ +} + +/* + *-------------------------------------------------------------- + * + * Tk_DeleteEventHandler -- + * + * Delete a previously-created handler. + * + * Results: + * None. + * + * Side effects: + * If there existed a handler as described by the + * parameters, the handler is deleted so that proc + * will not be invoked again. + * + *-------------------------------------------------------------- + */ + +void +Tk_DeleteEventHandler(token, mask, proc, clientData) + Tk_Window token; /* Same as corresponding arguments passed */ + unsigned long mask; /* previously to Tk_CreateEventHandler. */ + Tk_EventProc *proc; + ClientData clientData; +{ + register TkEventHandler *handlerPtr; + register InProgress *ipPtr; + TkEventHandler *prevPtr; + register TkWindow *winPtr = (TkWindow *) token; + + /* + * Find the event handler to be deleted, or return + * immediately if it doesn't exist. + */ + + for (handlerPtr = winPtr->handlerList, prevPtr = NULL; ; + prevPtr = handlerPtr, handlerPtr = handlerPtr->nextPtr) { + if (handlerPtr == NULL) { + return; + } + if ((handlerPtr->mask == mask) && (handlerPtr->proc == proc) + && (handlerPtr->clientData == clientData)) { + break; + } + } + + /* + * If Tk_HandleEvent is about to process this handler, tell it to + * process the next one instead. + */ + + for (ipPtr = pendingPtr; ipPtr != NULL; ipPtr = ipPtr->nextPtr) { + if (ipPtr->nextHandler == handlerPtr) { + ipPtr->nextHandler = handlerPtr->nextPtr; + } + } + + /* + * Free resources associated with the handler. + */ + + if (prevPtr == NULL) { + winPtr->handlerList = handlerPtr->nextPtr; + } else { + prevPtr->nextPtr = handlerPtr->nextPtr; + } + ckfree((char *) handlerPtr); + + + /* + * No need to call XSelectInput: Tk always selects on all events + * for all windows (needed to support bindings on classes and "all"). + */ +} + +/*-------------------------------------------------------------- + * + * Tk_CreateGenericHandler -- + * + * Register a procedure to be called on each X event, regardless + * of display or window. Generic handlers are useful for capturing + * events that aren't associated with windows, or events for windows + * not managed by Tk. + * + * Results: + * None. + * + * Side Effects: + * From now on, whenever an X event is given to Tk_HandleEvent, + * invoke proc, giving it clientData and the event as arguments. + * + *-------------------------------------------------------------- + */ + +void +Tk_CreateGenericHandler(proc, clientData) + Tk_GenericProc *proc; /* Procedure to call on every event. */ + ClientData clientData; /* One-word value to pass to proc. */ +{ + GenericHandler *handlerPtr; + + handlerPtr = (GenericHandler *) ckalloc (sizeof (GenericHandler)); + + handlerPtr->proc = proc; + handlerPtr->clientData = clientData; + handlerPtr->deleteFlag = 0; + handlerPtr->nextPtr = NULL; + if (genericList == NULL) { + genericList = handlerPtr; + } else { + lastGenericPtr->nextPtr = handlerPtr; + } + lastGenericPtr = handlerPtr; +} + +/* + *-------------------------------------------------------------- + * + * Tk_DeleteGenericHandler -- + * + * Delete a previously-created generic handler. + * + * Results: + * None. + * + * Side Effects: + * If there existed a handler as described by the parameters, + * that handler is logically deleted so that proc will not be + * invoked again. The physical deletion happens in the event + * loop in Tk_HandleEvent. + * + *-------------------------------------------------------------- + */ + +void +Tk_DeleteGenericHandler(proc, clientData) + Tk_GenericProc *proc; + ClientData clientData; +{ + GenericHandler * handler; + + for (handler = genericList; handler; handler = handler->nextPtr) { + if ((handler->proc == proc) && (handler->clientData == clientData)) { + handler->deleteFlag = 1; + } + } +} + +/* + *-------------------------------------------------------------- + * + * Tk_HandleEvent -- + * + * Given an event, invoke all the handlers that have + * been registered for the event. + * + * Results: + * None. + * + * Side effects: + * Depends on the handlers. + * + *-------------------------------------------------------------- + */ + +void +Tk_HandleEvent(eventPtr) + XEvent *eventPtr; /* Event to dispatch. */ +{ + register TkEventHandler *handlerPtr; + register GenericHandler *genericPtr; + register GenericHandler *genPrevPtr; + TkWindow *winPtr; + unsigned long mask; + InProgress ip; + Window handlerWindow; + TkDisplay *dispPtr; + Tcl_Interp *interp = (Tcl_Interp *) NULL; + + /* + * Next, invoke all the generic event handlers (those that are + * invoked for all events). If a generic event handler reports that + * an event is fully processed, go no further. + */ + + for (genPrevPtr = NULL, genericPtr = genericList; genericPtr != NULL; ) { + if (genericPtr->deleteFlag) { + if (!genericHandlersActive) { + GenericHandler *tmpPtr; + + /* + * This handler needs to be deleted and there are no + * calls pending through the handler, so now is a safe + * time to delete it. + */ + + tmpPtr = genericPtr->nextPtr; + if (genPrevPtr == NULL) { + genericList = tmpPtr; + } else { + genPrevPtr->nextPtr = tmpPtr; + } + if (tmpPtr == NULL) { + lastGenericPtr = genPrevPtr; + } + (void) ckfree((char *) genericPtr); + genericPtr = tmpPtr; + continue; + } + } else { + int done; + + genericHandlersActive++; + done = (*genericPtr->proc)(genericPtr->clientData, eventPtr); + genericHandlersActive--; + if (done) { + return; + } + } + genPrevPtr = genericPtr; + genericPtr = genPrevPtr->nextPtr; + } + + /* + * If the event is a MappingNotify event, find its display and + * refresh the keyboard mapping information for the display. + * After that there's nothing else to do with the event, so just + * quit. + */ + + if (eventPtr->type == MappingNotify) { + dispPtr = TkGetDisplay(eventPtr->xmapping.display); + if (dispPtr != NULL) { + XRefreshKeyboardMapping(&eventPtr->xmapping); + dispPtr->bindInfoStale = 1; + } + return; + } + + /* + * Events selected by StructureNotify require special handling. + * They look the same as those selected by SubstructureNotify. + * The only difference is whether the "event" and "window" fields + * are the same. Compare the two fields and convert StructureNotify + * to SubstructureNotify if necessary. + */ + + handlerWindow = eventPtr->xany.window; + mask = eventMasks[eventPtr->xany.type]; + if (mask == StructureNotifyMask) { + if (eventPtr->xmap.event != eventPtr->xmap.window) { + mask = SubstructureNotifyMask; + handlerWindow = eventPtr->xmap.event; + } + } + winPtr = (TkWindow *) Tk_IdToWindow(eventPtr->xany.display, handlerWindow); + if (winPtr == NULL) { + + /* + * There isn't a TkWindow structure for this window. + * However, if the event is a PropertyNotify event then call + * the selection manager (it deals beneath-the-table with + * certain properties). + */ + + if (eventPtr->type == PropertyNotify) { + TkSelPropProc(eventPtr); + } + return; + } + + /* + * Once a window has started getting deleted, don't process any more + * events for it except for the DestroyNotify event. This check is + * needed because a DestroyNotify handler could re-invoke the event + * loop, causing other pending events to be handled for the window + * (the window doesn't get totally expunged from our tables until + * after the DestroyNotify event has been completely handled). + */ + + if ((winPtr->flags & TK_ALREADY_DEAD) + && (eventPtr->type != DestroyNotify)) { + return; + } + + if (winPtr->mainPtr != NULL) { + + /* + * Protect interpreter for this window from possible deletion + * while we are dealing with the event for this window. Thus, + * widget writers do not have to worry about protecting the + * interpreter in their own code. + */ + + interp = winPtr->mainPtr->interp; + Tcl_Preserve((ClientData) interp); + + /* + * Call focus-related code to look at FocusIn, FocusOut, Enter, + * and Leave events; depending on its return value, ignore the + * event. + */ + + if ((mask & (FocusChangeMask|EnterWindowMask|LeaveWindowMask)) + && !TkFocusFilterEvent(winPtr, eventPtr)) { + Tcl_Release((ClientData) interp); + return; + } + + /* + * Redirect KeyPress and KeyRelease events to the focus window, + * or ignore them entirely if there is no focus window. + */ + + if (mask & (KeyPressMask|KeyReleaseMask)) { + winPtr->dispPtr->lastEventTime = eventPtr->xkey.time; + winPtr = TkFocusKeyEvent(winPtr, eventPtr); + if (winPtr == NULL) { + Tcl_Release((ClientData) interp); + return; + } + } + + /* + * Call a grab-related procedure to do special processing on + * pointer events. + */ + + if (mask & (ButtonPressMask|ButtonReleaseMask|PointerMotionMask + |EnterWindowMask|LeaveWindowMask)) { + if (mask & (ButtonPressMask|ButtonReleaseMask)) { + winPtr->dispPtr->lastEventTime = eventPtr->xbutton.time; + } else if (mask & PointerMotionMask) { + winPtr->dispPtr->lastEventTime = eventPtr->xmotion.time; + } else { + winPtr->dispPtr->lastEventTime = eventPtr->xcrossing.time; + } + if (TkPointerEvent(eventPtr, winPtr) == 0) { + goto done; + } + } + } + +#ifdef TK_USE_INPUT_METHODS + /* + * Pass the event to the input method(s), if there are any, and + * discard the event if the input method(s) insist. Create the + * input context for the window if it hasn't already been done + * (XFilterEvent needs this context). + */ + + if (!(winPtr->flags & TK_CHECKED_IC)) { + if (winPtr->dispPtr->inputMethod != NULL) { + winPtr->inputContext = XCreateIC( + winPtr->dispPtr->inputMethod, XNInputStyle, + XIMPreeditNothing|XIMStatusNothing, + XNClientWindow, winPtr->window, + XNFocusWindow, winPtr->window, NULL); + } + winPtr->flags |= TK_CHECKED_IC; + } + if (XFilterEvent(eventPtr, None)) { + goto done; + } +#endif /* TK_USE_INPUT_METHODS */ + + /* + * For events where it hasn't already been done, update the current + * time in the display. + */ + + if (eventPtr->type == PropertyNotify) { + winPtr->dispPtr->lastEventTime = eventPtr->xproperty.time; + } + + /* + * There's a potential interaction here with Tk_DeleteEventHandler. + * Read the documentation for pendingPtr. + */ + + ip.eventPtr = eventPtr; + ip.winPtr = winPtr; + ip.nextHandler = NULL; + ip.nextPtr = pendingPtr; + pendingPtr = &ip; + if (mask == 0) { + if ((eventPtr->type == SelectionClear) + || (eventPtr->type == SelectionRequest) + || (eventPtr->type == SelectionNotify)) { + TkSelEventProc((Tk_Window) winPtr, eventPtr); + } else if ((eventPtr->type == ClientMessage) + && (eventPtr->xclient.message_type == + Tk_InternAtom((Tk_Window) winPtr, "WM_PROTOCOLS"))) { + TkWmProtocolEventProc(winPtr, eventPtr); + } + } else { + for (handlerPtr = winPtr->handlerList; handlerPtr != NULL; ) { + if ((handlerPtr->mask & mask) != 0) { + ip.nextHandler = handlerPtr->nextPtr; + (*(handlerPtr->proc))(handlerPtr->clientData, eventPtr); + handlerPtr = ip.nextHandler; + } else { + handlerPtr = handlerPtr->nextPtr; + } + } + + /* + * Pass the event to the "bind" command mechanism. But, don't + * do this for SubstructureNotify events. The "bind" command + * doesn't support them anyway, and it's easier to filter out + * these events here than in the lower-level procedures. + */ + + if ((ip.winPtr != None) && (mask != SubstructureNotifyMask)) { + TkBindEventProc(winPtr, eventPtr); + } + } + pendingPtr = ip.nextPtr; +done: + + /* + * Release the interpreter for this window so that it can be potentially + * deleted if requested. + */ + + if (interp != (Tcl_Interp *) NULL) { + Tcl_Release((ClientData) interp); + } +} + +/* + *-------------------------------------------------------------- + * + * TkEventDeadWindow -- + * + * This procedure is invoked when it is determined that + * a window is dead. It cleans up event-related information + * about the window. + * + * Results: + * None. + * + * Side effects: + * Various things get cleaned up and recycled. + * + *-------------------------------------------------------------- + */ + +void +TkEventDeadWindow(winPtr) + TkWindow *winPtr; /* Information about the window + * that is being deleted. */ +{ + register TkEventHandler *handlerPtr; + register InProgress *ipPtr; + + /* + * While deleting all the handlers, be careful to check for + * Tk_HandleEvent being about to process one of the deleted + * handlers. If it is, tell it to quit (all of the handlers + * are being deleted). + */ + + while (winPtr->handlerList != NULL) { + handlerPtr = winPtr->handlerList; + winPtr->handlerList = handlerPtr->nextPtr; + for (ipPtr = pendingPtr; ipPtr != NULL; ipPtr = ipPtr->nextPtr) { + if (ipPtr->nextHandler == handlerPtr) { + ipPtr->nextHandler = NULL; + } + if (ipPtr->winPtr == winPtr) { + ipPtr->winPtr = None; + } + } + ckfree((char *) handlerPtr); + } +} + +/* + *---------------------------------------------------------------------- + * + * TkCurrentTime -- + * + * Try to deduce the current time. "Current time" means the time + * of the event that led to the current code being executed, which + * means the time in the most recently-nested invocation of + * Tk_HandleEvent. + * + * Results: + * The return value is the time from the current event, or + * CurrentTime if there is no current event or if the current + * event contains no time. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +Time +TkCurrentTime(dispPtr) + TkDisplay *dispPtr; /* Display for which the time is desired. */ +{ + register XEvent *eventPtr; + + if (pendingPtr == NULL) { + return dispPtr->lastEventTime; + } + eventPtr = pendingPtr->eventPtr; + switch (eventPtr->type) { + case ButtonPress: + case ButtonRelease: + return eventPtr->xbutton.time; + case KeyPress: + case KeyRelease: + return eventPtr->xkey.time; + case MotionNotify: + return eventPtr->xmotion.time; + case EnterNotify: + case LeaveNotify: + return eventPtr->xcrossing.time; + case PropertyNotify: + return eventPtr->xproperty.time; + } + return dispPtr->lastEventTime; +} + +/* + *---------------------------------------------------------------------- + * + * Tk_RestrictEvents -- + * + * This procedure is used to globally restrict the set of events + * that will be dispatched. The restriction is done by filtering + * all incoming X events through a procedure that determines + * whether they are to be processed immediately, deferred, or + * discarded. + * + * Results: + * The return value is the previous restriction procedure in effect, + * if there was one, or NULL if there wasn't. + * + * Side effects: + * From now on, proc will be called to determine whether to process, + * defer or discard each incoming X event. + * + *---------------------------------------------------------------------- + */ + +Tk_RestrictProc * +Tk_RestrictEvents(proc, arg, prevArgPtr) + Tk_RestrictProc *proc; /* Procedure to call for each incoming + * event. */ + ClientData arg; /* Arbitrary argument to pass to proc. */ + ClientData *prevArgPtr; /* Place to store information about previous + * argument. */ +{ + Tk_RestrictProc *prev; + + prev = restrictProc; + *prevArgPtr = restrictArg; + restrictProc = proc; + restrictArg = arg; + return prev; +} + +/* + *---------------------------------------------------------------------- + * + * Tk_QueueWindowEvent -- + * + * Given an X-style window event, this procedure adds it to the + * Tcl event queue at the given position. This procedure also + * performs mouse motion event collapsing if possible. + * + * Results: + * None. + * + * Side effects: + * Adds stuff to the event queue, which will eventually be + * processed. + * + *---------------------------------------------------------------------- + */ + +void +Tk_QueueWindowEvent(eventPtr, position) + XEvent *eventPtr; /* Event to add to queue. This + * procedures copies it before adding + * it to the queue. */ + Tcl_QueuePosition position; /* Where to put it on the queue: + * TCL_QUEUE_TAIL, TCL_QUEUE_HEAD, + * or TCL_QUEUE_MARK. */ +{ + TkWindowEvent *wevPtr; + TkDisplay *dispPtr; + + /* + * Find our display structure for the event's display. + */ + + for (dispPtr = tkDisplayList; ; dispPtr = dispPtr->nextPtr) { + if (dispPtr == NULL) { + return; + } + if (dispPtr->display == eventPtr->xany.display) { + break; + } + } + + if ((dispPtr->delayedMotionPtr != NULL) && (position == TCL_QUEUE_TAIL)) { + if ((eventPtr->type == MotionNotify) && (eventPtr->xmotion.window + == dispPtr->delayedMotionPtr->event.xmotion.window)) { + /* + * The new event is a motion event in the same window as the + * saved motion event. Just replace the saved event with the + * new one. + */ + + dispPtr->delayedMotionPtr->event = *eventPtr; + return; + } else if ((eventPtr->type != GraphicsExpose) + && (eventPtr->type != NoExpose) + && (eventPtr->type != Expose)) { + /* + * The new event may conflict with the saved motion event. Queue + * the saved motion event now so that it will be processed before + * the new event. + */ + + Tcl_QueueEvent(&dispPtr->delayedMotionPtr->header, position); + dispPtr->delayedMotionPtr = NULL; + Tcl_CancelIdleCall(DelayedMotionProc, (ClientData) dispPtr); + } + } + + wevPtr = (TkWindowEvent *) ckalloc(sizeof(TkWindowEvent)); + wevPtr->header.proc = WindowEventProc; + wevPtr->event = *eventPtr; + if ((eventPtr->type == MotionNotify) && (position == TCL_QUEUE_TAIL)) { + /* + * The new event is a motion event so don't queue it immediately; + * save it around in case another motion event arrives that it can + * be collapsed with. + */ + + if (dispPtr->delayedMotionPtr != NULL) { + panic("Tk_QueueWindowEvent found unexpected delayed motion event"); + } + dispPtr->delayedMotionPtr = wevPtr; + Tcl_DoWhenIdle(DelayedMotionProc, (ClientData) dispPtr); + } else { + Tcl_QueueEvent(&wevPtr->header, position); + } +} + +/* + *--------------------------------------------------------------------------- + * + * TkQueueEventForAllChildren -- + * + * Given an XEvent, recursively queue the event for this window and + * all non-toplevel children of the given window. + * + * Results: + * None. + * + * Side effects: + * Events queued. + * + *--------------------------------------------------------------------------- + */ + +void +TkQueueEventForAllChildren(winPtr, eventPtr) + TkWindow *winPtr; /* Window to which event is sent. */ + XEvent *eventPtr; /* The event to be sent. */ +{ + TkWindow *childPtr; + + eventPtr->xany.window = winPtr->window; + Tk_QueueWindowEvent(eventPtr, TCL_QUEUE_TAIL); + + childPtr = winPtr->childList; + while (childPtr != NULL) { + if (!Tk_IsTopLevel(childPtr)) { + TkQueueEventForAllChildren(childPtr, eventPtr); + } + childPtr = childPtr->nextPtr; + } +} + +/* + *---------------------------------------------------------------------- + * + * WindowEventProc -- + * + * This procedure is called by Tcl_DoOneEvent when a window event + * reaches the front of the event queue. This procedure is responsible + * for actually handling the event. + * + * Results: + * Returns 1 if the event was handled, meaning it should be removed + * from the queue. Returns 0 if the event was not handled, meaning + * it should stay on the queue. The event isn't handled if the + * TCL_WINDOW_EVENTS bit isn't set in flags, if a restrict proc + * prevents the event from being handled. + * + * Side effects: + * Whatever the event handlers for the event do. + * + *---------------------------------------------------------------------- + */ + +static int +WindowEventProc(evPtr, flags) + Tcl_Event *evPtr; /* Event to service. */ + int flags; /* Flags that indicate what events to + * handle, such as TCL_WINDOW_EVENTS. */ +{ + TkWindowEvent *wevPtr = (TkWindowEvent *) evPtr; + Tk_RestrictAction result; + + if (!(flags & TCL_WINDOW_EVENTS)) { + return 0; + } + if (restrictProc != NULL) { + result = (*restrictProc)(restrictArg, &wevPtr->event); + if (result != TK_PROCESS_EVENT) { + if (result == TK_DEFER_EVENT) { + return 0; + } else { + /* + * TK_DELETE_EVENT: return and say we processed the event, + * even though we didn't do anything at all. + */ + return 1; + } + } + } + Tk_HandleEvent(&wevPtr->event); + return 1; +} + +/* + *---------------------------------------------------------------------- + * + * DelayedMotionProc -- + * + * This procedure is invoked as an idle handler when a mouse motion + * event has been delayed. It queues the delayed event so that it + * will finally be serviced. + * + * Results: + * None. + * + * Side effects: + * The delayed mouse motion event gets added to the Tcl event + * queue for servicing. + * + *---------------------------------------------------------------------- + */ + +static void +DelayedMotionProc(clientData) + ClientData clientData; /* Pointer to display containing a delayed + * motion event to be serviced. */ +{ + TkDisplay *dispPtr = (TkDisplay *) clientData; + + if (dispPtr->delayedMotionPtr == NULL) { + panic("DelayedMotionProc found no delayed mouse motion event"); + } + Tcl_QueueEvent(&dispPtr->delayedMotionPtr->header, TCL_QUEUE_TAIL); + dispPtr->delayedMotionPtr = NULL; +} + +/* + *-------------------------------------------------------------- + * + * Tk_MainLoop -- + * + * Call Tcl_DoOneEvent over and over again in an infinite + * loop as long as there exist any main windows. + * + * Results: + * None. + * + * Side effects: + * Arbitrary; depends on handlers for events. + * + *-------------------------------------------------------------- + */ + +void +Tk_MainLoop() +{ + while (Tk_GetNumMainWindows() > 0) { + Tcl_DoOneEvent(0); + } +} |