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-rw-r--r--tcl8.6/unix/tclXtNotify.c667
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diff --git a/tcl8.6/unix/tclXtNotify.c b/tcl8.6/unix/tclXtNotify.c
new file mode 100644
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+++ b/tcl8.6/unix/tclXtNotify.c
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+/*
+ * 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:
+ */