Merge commit '29ccecd87709feda60d191f6aaba324ccad91f55' as 'tcl8.6'

1 files changed, 667 insertions, 0 deletions

diff --git a/tcl8.6/unix/tclXtNotify.c b/tcl8.6/unix/tclXtNotify.c
new file mode 100644
index 0000000..a5d92d6
--- /dev/null
+++ b/tcl8.6/unix/tclXtNotify.c
@@ -0,0 +1,667 @@
+/*
+ * tclXtNotify.c --
+ *
+ *	This file contains the notifier driver implementation for the Xt
+ *	intrinsics.
+ *
+ * Copyright (c) 1997 by Sun Microsystems, Inc.
+ *
+ * See the file "license.terms" for information on usage and redistribution of
+ * this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ */
+
+#ifndef USE_TCL_STUBS
+#   define USE_TCL_STUBS
+#endif
+#include <X11/Intrinsic.h>
+#include "tclInt.h"
+
+/*
+ * This structure is used to keep track of the notifier info for a a
+ * registered file.
+ */
+
+typedef struct FileHandler {
+    int fd;
+    int mask;			/* Mask of desired events: TCL_READABLE,
+				 * etc. */
+    int readyMask;		/* Events that have been seen since the last
+				 * time FileHandlerEventProc was called for
+				 * this file. */
+    XtInputId read;		/* Xt read callback handle. */
+    XtInputId write;		/* Xt write callback handle. */
+    XtInputId except;		/* Xt exception callback handle. */
+    Tcl_FileProc *proc;		/* Procedure to call, in the style of
+				 * Tcl_CreateFileHandler. */
+    ClientData clientData;	/* Argument to pass to proc. */
+    struct FileHandler *nextPtr;/* Next in list of all files we care about. */
+} FileHandler;
+
+/*
+ * The following structure is what is added to the Tcl event queue when file
+ * handlers are ready to fire.
+ */
+
+typedef struct FileHandlerEvent {
+    Tcl_Event header;		/* Information that is standard for all
+				 * events. */
+    int fd;			/* File descriptor that is ready. Used to find
+				 * the FileHandler structure for the file
+				 * (can't point directly to the FileHandler
+				 * structure because it could go away while
+				 * the event is queued). */
+} FileHandlerEvent;
+
+/*
+ * The following static structure contains the state information for the Xt
+ * based implementation of the Tcl notifier.
+ */
+
+static struct NotifierState {
+    XtAppContext appContext;	/* The context used by the Xt notifier. Can be
+				 * set with TclSetAppContext. */
+    int appContextCreated;	/* Was it created by us? */
+    XtIntervalId currentTimeout;/* Handle of current timer. */
+    FileHandler *firstFileHandlerPtr;
+				/* Pointer to head of file handler list. */
+} notifier;
+
+/*
+ * The following static indicates whether this module has been initialized.
+ */
+
+static int initialized = 0;
+
+/*
+ * Static routines defined in this file.
+ */
+
+static int		FileHandlerEventProc(Tcl_Event *evPtr, int flags);
+static void		FileProc(XtPointer clientData, int *source,
+			    XtInputId *id);
+static void		NotifierExitHandler(ClientData clientData);
+static void		TimerProc(XtPointer clientData, XtIntervalId *id);
+static void		CreateFileHandler(int fd, int mask,
+			    Tcl_FileProc *proc, ClientData clientData);
+static void		DeleteFileHandler(int fd);
+static void		SetTimer(const Tcl_Time * timePtr);
+static int		WaitForEvent(const Tcl_Time * timePtr);
+
+/*
+ * Functions defined in this file for use by users of the Xt Notifier:
+ */
+
+MODULE_SCOPE void InitNotifier(void);
+MODULE_SCOPE XtAppContext TclSetAppContext(XtAppContext ctx);
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclSetAppContext --
+ *
+ *	Set the notifier application context.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Sets the application context used by the notifier. Panics if the
+ *	context is already set when called.
+ *
+ *----------------------------------------------------------------------
+ */
+
+XtAppContext
+TclSetAppContext(
+    XtAppContext appContext)
+{
+    if (!initialized) {
+	InitNotifier();
+    }
+
+    /*
+     * If we already have a context we check whether we were asked to set a
+     * new context. If so, we panic because we try to prevent switching
+     * contexts by mistake. Otherwise, we return the one we have.
+     */
+
+    if (notifier.appContext != NULL) {
+	if (appContext != NULL) {
+	    /*
+	     * We already have a context. We do not allow switching contexts
+	     * after initialization, so we panic.
+	     */
+
+	    Tcl_Panic("TclSetAppContext:  multiple application contexts");
+	}
+    } else {
+	/*
+	 * If we get here we have not yet gotten a context, so either create
+	 * one or use the one supplied by our caller.
+	 */
+
+	if (appContext == NULL) {
+	    /*
+	     * We must create a new context and tell our caller what it is, so
+	     * she can use it too.
+	     */
+
+	    notifier.appContext = XtCreateApplicationContext();
+	    notifier.appContextCreated = 1;
+	} else {
+	    /*
+	     * Otherwise we remember the context that our caller gave us and
+	     * use it.
+	     */
+
+	    notifier.appContextCreated = 0;
+	    notifier.appContext = appContext;
+	}
+    }
+
+    return notifier.appContext;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * InitNotifier --
+ *
+ *	Initializes the notifier state.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Creates a new exit handler.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+InitNotifier(void)
+{
+    Tcl_NotifierProcs np;
+
+    /*
+     * Only reinitialize if we are not in exit handling. The notifier can get
+     * reinitialized after its own exit handler has run, because of exit
+     * handlers for the I/O and timer sub-systems (order dependency).
+     */
+
+    if (TclInExit()) {
+	return;
+    }
+
+    np.createFileHandlerProc = CreateFileHandler;
+    np.deleteFileHandlerProc = DeleteFileHandler;
+    np.setTimerProc = SetTimer;
+    np.waitForEventProc = WaitForEvent;
+    np.initNotifierProc = Tcl_InitNotifier;
+    np.finalizeNotifierProc = Tcl_FinalizeNotifier;
+    np.alertNotifierProc = Tcl_AlertNotifier;
+    np.serviceModeHookProc = Tcl_ServiceModeHook;
+    Tcl_SetNotifier(&np);
+
+    /*
+     * DO NOT create the application context yet; doing so would prevent
+     * external applications from setting it for us to their own ones.
+     */
+
+    initialized = 1;
+    memset(&np, 0, sizeof(np));
+    Tcl_CreateExitHandler(NotifierExitHandler, NULL);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * NotifierExitHandler --
+ *
+ *	This function is called to cleanup the notifier state before Tcl is
+ *	unloaded.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Destroys the notifier window.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+NotifierExitHandler(
+    ClientData clientData)	/* Not used. */
+{
+    if (notifier.currentTimeout != 0) {
+	XtRemoveTimeOut(notifier.currentTimeout);
+    }
+    for (; notifier.firstFileHandlerPtr != NULL; ) {
+	Tcl_DeleteFileHandler(notifier.firstFileHandlerPtr->fd);
+    }
+    if (notifier.appContextCreated) {
+	XtDestroyApplicationContext(notifier.appContext);
+	notifier.appContextCreated = 0;
+	notifier.appContext = NULL;
+    }
+    initialized = 0;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * SetTimer --
+ *
+ *	This procedure sets the current notifier timeout value.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Replaces any previous timer.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+SetTimer(
+    const Tcl_Time *timePtr)		/* Timeout value, may be NULL. */
+{
+    long timeout;
+
+    if (!initialized) {
+	InitNotifier();
+    }
+
+    TclSetAppContext(NULL);
+    if (notifier.currentTimeout != 0) {
+	XtRemoveTimeOut(notifier.currentTimeout);
+    }
+    if (timePtr) {
+	timeout = timePtr->sec * 1000 + timePtr->usec / 1000;
+	notifier.currentTimeout = XtAppAddTimeOut(notifier.appContext,
+		(unsigned long) timeout, TimerProc, NULL);
+    } else {
+	notifier.currentTimeout = 0;
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TimerProc --
+ *
+ *	This procedure is the XtTimerCallbackProc used to handle timeouts.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Processes all queued events.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+TimerProc(
+    XtPointer clientData, /* Not used. */
+    XtIntervalId *id)
+{
+    if (*id != notifier.currentTimeout) {
+	return;
+    }
+    notifier.currentTimeout = 0;
+
+    Tcl_ServiceAll();
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * CreateFileHandler --
+ *
+ *	This procedure registers a file handler with the Xt notifier.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Creates a new file handler structure and registers one or more input
+ *	procedures with Xt.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+CreateFileHandler(
+    int fd,			/* Handle of stream to watch. */
+    int mask,			/* OR'ed combination of TCL_READABLE,
+				 * TCL_WRITABLE, and TCL_EXCEPTION: indicates
+				 * conditions under which proc should be
+				 * called. */
+    Tcl_FileProc *proc,		/* Procedure to call for each selected
+				 * event. */
+    ClientData clientData)	/* Arbitrary data to pass to proc. */
+{
+    FileHandler *filePtr;
+
+    if (!initialized) {
+	InitNotifier();
+    }
+
+    TclSetAppContext(NULL);
+
+    for (filePtr = notifier.firstFileHandlerPtr; filePtr != NULL;
+	    filePtr = filePtr->nextPtr) {
+	if (filePtr->fd == fd) {
+	    break;
+	}
+    }
+    if (filePtr == NULL) {
+	filePtr = ckalloc(sizeof(FileHandler));
+	filePtr->fd = fd;
+	filePtr->read = 0;
+	filePtr->write = 0;
+	filePtr->except = 0;
+	filePtr->readyMask = 0;
+	filePtr->mask = 0;
+	filePtr->nextPtr = notifier.firstFileHandlerPtr;
+	notifier.firstFileHandlerPtr = filePtr;
+    }
+    filePtr->proc = proc;
+    filePtr->clientData = clientData;
+
+    /*
+     * Register the file with the Xt notifier, if it hasn't been done yet.
+     */
+
+    if (mask & TCL_READABLE) {
+	if (!(filePtr->mask & TCL_READABLE)) {
+	    filePtr->read = XtAppAddInput(notifier.appContext, fd,
+		    INT2PTR(XtInputReadMask), FileProc, filePtr);
+	}
+    } else {
+	if (filePtr->mask & TCL_READABLE) {
+	    XtRemoveInput(filePtr->read);
+	}
+    }
+    if (mask & TCL_WRITABLE) {
+	if (!(filePtr->mask & TCL_WRITABLE)) {
+	    filePtr->write = XtAppAddInput(notifier.appContext, fd,
+		    INT2PTR(XtInputWriteMask), FileProc, filePtr);
+	}
+    } else {
+	if (filePtr->mask & TCL_WRITABLE) {
+	    XtRemoveInput(filePtr->write);
+	}
+    }
+    if (mask & TCL_EXCEPTION) {
+	if (!(filePtr->mask & TCL_EXCEPTION)) {
+	    filePtr->except = XtAppAddInput(notifier.appContext, fd,
+		    INT2PTR(XtInputExceptMask), FileProc, filePtr);
+	}
+    } else {
+	if (filePtr->mask & TCL_EXCEPTION) {
+	    XtRemoveInput(filePtr->except);
+	}
+    }
+    filePtr->mask = mask;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * DeleteFileHandler --
+ *
+ *	Cancel a previously-arranged callback arrangement for a file.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	If a callback was previously registered on file, remove it.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+DeleteFileHandler(
+    int fd)			/* Stream id for which to remove callback
+				 * procedure. */
+{
+    FileHandler *filePtr, *prevPtr;
+
+    if (!initialized) {
+	InitNotifier();
+    }
+
+    TclSetAppContext(NULL);
+
+    /*
+     * Find the entry for the given file (and return if there isn't one).
+     */
+
+    for (prevPtr = NULL, filePtr = notifier.firstFileHandlerPtr; ;
+	    prevPtr = filePtr, filePtr = filePtr->nextPtr) {
+	if (filePtr == NULL) {
+	    return;
+	}
+	if (filePtr->fd == fd) {
+	    break;
+	}
+    }
+
+    /*
+     * Clean up information in the callback record.
+     */
+
+    if (prevPtr == NULL) {
+	notifier.firstFileHandlerPtr = filePtr->nextPtr;
+    } else {
+	prevPtr->nextPtr = filePtr->nextPtr;
+    }
+    if (filePtr->mask & TCL_READABLE) {
+	XtRemoveInput(filePtr->read);
+    }
+    if (filePtr->mask & TCL_WRITABLE) {
+	XtRemoveInput(filePtr->write);
+    }
+    if (filePtr->mask & TCL_EXCEPTION) {
+	XtRemoveInput(filePtr->except);
+    }
+    ckfree(filePtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * FileProc --
+ *
+ *	These procedures are called by Xt when a file becomes readable,
+ *	writable, or has an exception.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Makes an entry on the Tcl event queue if the event is interesting.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+FileProc(
+    XtPointer clientData,
+    int *fd,
+    XtInputId *id)
+{
+    FileHandler *filePtr = (FileHandler *)clientData;
+    FileHandlerEvent *fileEvPtr;
+    int mask = 0;
+
+    /*
+     * Determine which event happened.
+     */
+
+    if (*id == filePtr->read) {
+	mask = TCL_READABLE;
+    } else if (*id == filePtr->write) {
+	mask = TCL_WRITABLE;
+    } else if (*id == filePtr->except) {
+	mask = TCL_EXCEPTION;
+    }
+
+    /*
+     * Ignore unwanted or duplicate events.
+     */
+
+    if (!(filePtr->mask & mask) || (filePtr->readyMask & mask)) {
+	return;
+    }
+
+    /*
+     * This is an interesting event, so put it onto the event queue.
+     */
+
+    filePtr->readyMask |= mask;
+    fileEvPtr = ckalloc(sizeof(FileHandlerEvent));
+    fileEvPtr->header.proc = FileHandlerEventProc;
+    fileEvPtr->fd = filePtr->fd;
+    Tcl_QueueEvent((Tcl_Event *) fileEvPtr, TCL_QUEUE_TAIL);
+
+    /*
+     * Process events on the Tcl event queue before returning to Xt.
+     */
+
+    Tcl_ServiceAll();
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * FileHandlerEventProc --
+ *
+ *	This procedure is called by Tcl_ServiceEvent when a file event reaches
+ *	the front of the event queue. This procedure is responsible for
+ *	actually handling the event by invoking the callback for the file
+ *	handler.
+ *
+ * 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 only time the event isn't handled is if the
+ *	TCL_FILE_EVENTS flag bit isn't set.
+ *
+ * Side effects:
+ *	Whatever the file handler's callback procedure does.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+FileHandlerEventProc(
+    Tcl_Event *evPtr,		/* Event to service. */
+    int flags)			/* Flags that indicate what events to handle,
+				 * such as TCL_FILE_EVENTS. */
+{
+    FileHandler *filePtr;
+    FileHandlerEvent *fileEvPtr = (FileHandlerEvent *) evPtr;
+    int mask;
+
+    if (!(flags & TCL_FILE_EVENTS)) {
+	return 0;
+    }
+
+    /*
+     * Search through the file handlers to find the one whose handle matches
+     * the event. We do this rather than keeping a pointer to the file handler
+     * directly in the event, so that the handler can be deleted while the
+     * event is queued without leaving a dangling pointer.
+     */
+
+    for (filePtr = notifier.firstFileHandlerPtr; filePtr != NULL;
+	    filePtr = filePtr->nextPtr) {
+	if (filePtr->fd != fileEvPtr->fd) {
+	    continue;
+	}
+
+	/*
+	 * The code is tricky for two reasons:
+	 * 1. The file handler's desired events could have changed since the
+	 *    time when the event was queued, so AND the ready mask with the
+	 *    desired mask.
+	 * 2. The file could have been closed and re-opened since the time
+	 *    when the event was queued. This is why the ready mask is stored
+	 *    in the file handler rather than the queued event: it will be
+	 *    zeroed when a new file handler is created for the newly opened
+	 *    file.
+	 */
+
+	mask = filePtr->readyMask & filePtr->mask;
+	filePtr->readyMask = 0;
+	if (mask != 0) {
+	    filePtr->proc(filePtr->clientData, mask);
+	}
+	break;
+    }
+    return 1;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * WaitForEvent --
+ *
+ *	This function is called by Tcl_DoOneEvent to wait for new events on
+ *	the message queue. If the block time is 0, then Tcl_WaitForEvent just
+ *	polls without blocking.
+ *
+ * Results:
+ *	Returns 1 if an event was found, else 0. This ensures that
+ *	Tcl_DoOneEvent will return 1, even if the event is handled by non-Tcl
+ *	code.
+ *
+ * Side effects:
+ *	Queues file events that are detected by the select.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+WaitForEvent(
+    const Tcl_Time *timePtr)		/* Maximum block time, or NULL. */
+{
+    int timeout;
+
+    if (!initialized) {
+	InitNotifier();
+    }
+
+    TclSetAppContext(NULL);
+
+    if (timePtr) {
+	timeout = timePtr->sec * 1000 + timePtr->usec / 1000;
+	if (timeout == 0) {
+	    if (XtAppPending(notifier.appContext)) {
+		goto process;
+	    } else {
+		return 0;
+	    }
+	} else {
+	    Tcl_SetTimer(timePtr);
+	}
+    }
+
+  process:
+    XtAppProcessEvent(notifier.appContext, XtIMAll);
+    return 1;
+}
+
+/*
+ * Local Variables:
+ * mode: c
+ * c-basic-offset: 4
+ * fill-column: 78
+ * End:
+ */