Putting TCL mods for Python under CVS.
diff --git a/Mac/tclmods/license-terms.txt b/Mac/tclmods/license-terms.txt
new file mode 100644
index 0000000..96ad966
--- /dev/null
+++ b/Mac/tclmods/license-terms.txt
@@ -0,0 +1,39 @@
+This software is copyrighted by the Regents of the University of
+California, Sun Microsystems, Inc., and other parties. The following
+terms apply to all files associated with the software unless explicitly
+disclaimed in individual files.
+
+The authors hereby grant permission to use, copy, modify, distribute,
+and license this software and its documentation for any purpose, provided
+that existing copyright notices are retained in all copies and that this
+notice is included verbatim in any distributions. No written agreement,
+license, or royalty fee is required for any of the authorized uses.
+Modifications to this software may be copyrighted by their authors
+and need not follow the licensing terms described here, provided that
+the new terms are clearly indicated on the first page of each file where
+they apply.
+
+IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY
+FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ARISING OUT OF THE USE OF THIS SOFTWARE, ITS DOCUMENTATION, OR ANY
+DERIVATIVES THEREOF, EVEN IF THE AUTHORS HAVE BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.
+
+THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES,
+INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT. THIS SOFTWARE
+IS PROVIDED ON AN "AS IS" BASIS, AND THE AUTHORS AND DISTRIBUTORS HAVE
+NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR
+MODIFICATIONS.
+
+GOVERNMENT USE: If you are acquiring this software on behalf of the
+U.S. government, the Government shall have only "Restricted Rights"
+in the software and related documentation as defined in the Federal
+Acquisition Regulations (FARs) in Clause 52.227.19 (c) (2). If you
+are acquiring the software on behalf of the Department of Defense, the
+software shall be classified as "Commercial Computer Software" and the
+Government shall have only "Restricted Rights" as defined in Clause
+252.227-7013 (c) (1) of DFARs. Notwithstanding the foregoing, the
+authors grant the U.S. Government and others acting in its behalf
+permission to use and distribute the software in accordance with the
+terms specified in this license.
diff --git a/Mac/tclmods/tclMacNotify.c b/Mac/tclmods/tclMacNotify.c
new file mode 100644
index 0000000..140dadb
--- /dev/null
+++ b/Mac/tclmods/tclMacNotify.c
@@ -0,0 +1,425 @@
+/*
+ * tclMacNotify.c --
+ *
+ * This file contains Macintosh-specific procedures for the notifier,
+ * which is the lowest-level part of the Tcl event loop. This file
+ * works together with ../generic/tclNotify.c.
+ *
+ * Copyright (c) 1995-1996 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: @(#) tclMacNotify.c 1.36 97/05/07 19:09:29
+ */
+
+#include "tclInt.h"
+#include "tclPort.h"
+#include "tclMac.h"
+#include "tclMacInt.h"
+#include <signal.h>
+#include <Events.h>
+#include <LowMem.h>
+#include <Processes.h>
+#include <Timer.h>
+
+
+/*
+ * This is necessary to work around a bug in Apple's Universal header files
+ * for the CFM68K libraries.
+ */
+
+#ifdef __CFM68K__
+#undef GetEventQueue
+extern pascal QHdrPtr GetEventQueue(void)
+ THREEWORDINLINE(0x2EBC, 0x0000, 0x014A);
+#pragma import list GetEventQueue
+#define GetEvQHdr() GetEventQueue()
+#endif
+
+/*
+ * The follwing static indicates whether this module has been initialized.
+ */
+
+static int initialized = 0;
+
+/*
+ * The following structure contains the state information for the
+ * notifier module.
+ */
+
+static struct {
+ int timerActive; /* 1 if timer is running. */
+ Tcl_Time timer; /* Time when next timer event is expected. */
+ int flags; /* OR'ed set of flags defined below. */
+ Point lastMousePosition; /* Last known mouse location. */
+ RgnHandle utilityRgn; /* Region used as the mouse region for
+ * WaitNextEvent and the update region when
+ * checking for events. */
+ Tcl_MacConvertEventPtr eventProcPtr;
+ /* This pointer holds the address of the
+ * function that will handle all incoming
+ * Macintosh events. */
+} notifier;
+
+/*
+ * The following defines are used in the flags field of the notifier struct.
+ */
+
+#define NOTIFY_IDLE (1<<1) /* Tcl_ServiceIdle should be called. */
+#define NOTIFY_TIMER (1<<2) /* Tcl_ServiceTimer should be called. */
+
+/*
+ * Prototypes for procedures that are referenced only in this file:
+ */
+
+static int HandleMacEvents _ANSI_ARGS_((void));
+static void InitNotifier _ANSI_ARGS_((void));
+static void NotifierExitHandler _ANSI_ARGS_((
+ ClientData clientData));
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * InitNotifier --
+ *
+ * Initializes the notifier structure.
+ *
+ * Results:
+ * None.
+ *
+ * Side effects:
+ * Creates a new exit handler.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+InitNotifier(void)
+{
+ initialized = 1;
+ memset(¬ifier, 0, sizeof(notifier));
+ Tcl_CreateExitHandler(NotifierExitHandler, NULL);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * NotifierExitHandler --
+ *
+ * This function is called to cleanup the notifier state before
+ * Tcl is unloaded.
+ *
+ * Results:
+ * None.
+ *
+ * Side effects:
+ * None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+NotifierExitHandler(
+ ClientData clientData) /* Not used. */
+{
+ initialized = 0;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * HandleMacEvents --
+ *
+ * This function checks for events from the Macintosh event queue.
+ *
+ * Results:
+ * Returns 1 if event found, 0 otherwise.
+ *
+ * Side effects:
+ * Pulls events off of the Mac event queue and then calls
+ * convertEventProc.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+HandleMacEvents(void)
+{
+ EventRecord theEvent;
+ int eventFound = 0, needsUpdate = 0;
+ Point currentMouse;
+ WindowRef windowRef;
+ Rect mouseRect;
+
+ /*
+ * Check for mouse moved events. These events aren't placed on the
+ * system event queue unless we call WaitNextEvent.
+ */
+
+ GetGlobalMouse(¤tMouse);
+ if ((notifier.eventProcPtr != NULL) &&
+ !EqualPt(currentMouse, notifier.lastMousePosition)) {
+ notifier.lastMousePosition = currentMouse;
+ theEvent.what = nullEvent;
+ if ((*notifier.eventProcPtr)(&theEvent) == true) {
+ eventFound = 1;
+ }
+ }
+
+ /*
+ * Check for update events. Since update events aren't generated
+ * until we call GetNextEvent, we may need to force a call to
+ * GetNextEvent, even if the queue is empty.
+ */
+
+ for (windowRef = FrontWindow(); windowRef != NULL;
+ windowRef = GetNextWindow(windowRef)) {
+ GetWindowUpdateRgn(windowRef, notifier.utilityRgn);
+ if (!EmptyRgn(notifier.utilityRgn)) {
+ needsUpdate = 1;
+ break;
+ }
+ }
+
+ /*
+ * Process events from the OS event queue.
+ */
+
+ while (needsUpdate || (GetEvQHdr()->qHead != NULL)) {
+ GetGlobalMouse(¤tMouse);
+ SetRect(&mouseRect, currentMouse.h, currentMouse.v,
+ currentMouse.h + 1, currentMouse.v + 1);
+ RectRgn(notifier.utilityRgn, &mouseRect);
+
+ WaitNextEvent(everyEvent, &theEvent, 5, notifier.utilityRgn);
+ needsUpdate = 0;
+ if ((notifier.eventProcPtr != NULL)
+ && ((*notifier.eventProcPtr)(&theEvent) == true)) {
+ eventFound = 1;
+ }
+ }
+
+ return eventFound;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_SetTimer --
+ *
+ * This procedure sets the current notifier timer value. The
+ * notifier will ensure that Tcl_ServiceAll() is called after
+ * the specified interval, even if no events have occurred.
+ *
+ * Results:
+ * None.
+ *
+ * Side effects:
+ * Replaces any previous timer.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+Tcl_SetTimer(
+ Tcl_Time *timePtr) /* New value for interval timer. */
+{
+ if (!timePtr) {
+ notifier.timerActive = 0;
+ } else {
+ /*
+ * Compute when the timer should fire.
+ */
+
+ TclpGetTime(¬ifier.timer);
+ notifier.timer.sec += timePtr->sec;
+ notifier.timer.usec += timePtr->usec;
+ if (notifier.timer.usec >= 1000000) {
+ notifier.timer.usec -= 1000000;
+ notifier.timer.sec += 1;
+ }
+ notifier.timerActive = 1;
+ }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_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 the event queue without blocking.
+ *
+ * Results:
+ * Always returns 0.
+ *
+ * Side effects:
+ * None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+Tcl_WaitForEvent(
+ Tcl_Time *timePtr) /* Maximum block time. */
+{
+ int found;
+ EventRecord macEvent;
+ long sleepTime = 5;
+ long ms;
+ Point currentMouse;
+ void * timerToken;
+ Rect mouseRect;
+
+ /*
+ * Compute the next timeout value.
+ */
+
+ if (!timePtr) {
+ ms = INT_MAX;
+ } else {
+ ms = (timePtr->sec * 1000) + (timePtr->usec / 1000);
+ }
+ timerToken = TclMacStartTimer((long) ms);
+
+ /*
+ * Poll the Mac event sources. This loop repeats until something
+ * happens: a timeout, a socket event, mouse motion, or some other
+ * window event. Note that we don't call WaitNextEvent if another
+ * event is found to avoid context switches. This effectively gives
+ * events coming in via WaitNextEvent a slightly lower priority.
+ */
+
+ found = 0;
+ if (notifier.utilityRgn == NULL) {
+ notifier.utilityRgn = NewRgn();
+ }
+
+ while (!found) {
+ /*
+ * Check for generated and queued events.
+ */
+
+ if (HandleMacEvents()) {
+ found = 1;
+ }
+
+ /*
+ * Check for time out.
+ */
+
+ if (!found && TclMacTimerExpired(timerToken)) {
+ found = 1;
+ }
+
+ /*
+ * Mod by Jack: poll for select() events. Code is in TclSelectNotify.c
+ */
+ {
+ int Tcl_PollSelectEvent(void);
+ if (!found && Tcl_PollSelectEvent())
+ found = 1;
+ }
+
+ /*
+ * Check for window events. We may receive a NULL event for
+ * various reasons. 1) the timer has expired, 2) a mouse moved
+ * event is occuring or 3) the os is giving us time for idle
+ * events. Note that we aren't sharing the processor very
+ * well here. We really ought to do a better job of calling
+ * WaitNextEvent for time slicing purposes.
+ */
+
+ if (!found) {
+ /*
+ * Set up mouse region so we will wake if the mouse is moved.
+ * We do this by defining the smallest possible region around
+ * the current mouse position.
+ */
+
+ GetGlobalMouse(¤tMouse);
+ SetRect(&mouseRect, currentMouse.h, currentMouse.v,
+ currentMouse.h + 1, currentMouse.v + 1);
+ RectRgn(notifier.utilityRgn, &mouseRect);
+
+ WaitNextEvent(everyEvent, &macEvent, sleepTime,
+ notifier.utilityRgn);
+
+ if (notifier.eventProcPtr != NULL) {
+ if ((*notifier.eventProcPtr)(&macEvent) == true) {
+ found = 1;
+ }
+ }
+ }
+ }
+ TclMacRemoveTimer(timerToken);
+ return 0;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_Sleep --
+ *
+ * Delay execution for the specified number of milliseconds. This
+ * is not a very good call to make. It will block the system -
+ * you will not even be able to switch applications.
+ *
+ * Results:
+ * None.
+ *
+ * Side effects:
+ * Time passes.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+Tcl_Sleep(
+ int ms) /* Number of milliseconds to sleep. */
+{
+ EventRecord dummy;
+ void *timerToken;
+
+ if (ms <= 0) {
+ return;
+ }
+
+ timerToken = TclMacStartTimer((long) ms);
+ while (1) {
+ WaitNextEvent(0, &dummy, (ms / 16.66) + 1, NULL);
+
+ if (TclMacTimerExpired(timerToken)) {
+ break;
+ }
+ }
+ TclMacRemoveTimer(timerToken);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_MacSetEventProc --
+ *
+ * This function sets the event handling procedure for the
+ * application. This function will be passed all incoming Mac
+ * events. This function usually controls the console or some
+ * other entity like Tk.
+ *
+ * Results:
+ * None.
+ *
+ * Side effects:
+ * Changes the event handling function.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+Tcl_MacSetEventProc(
+ Tcl_MacConvertEventPtr procPtr)
+{
+ notifier.eventProcPtr = procPtr;
+}
diff --git a/Mac/tclmods/tclSelectNotify.c b/Mac/tclmods/tclSelectNotify.c
new file mode 100644
index 0000000..ea35fc6
--- /dev/null
+++ b/Mac/tclmods/tclSelectNotify.c
@@ -0,0 +1,503 @@
+/*
+ * tclSelectNotify.c --
+ *
+ * Partial even handling, select only. This file is adapted from TclUnixNotify.c, and
+ * meant as an add-in for Mac (and possibly Windows) environments where select *is* available.
+ * TclMacNotify.c works together with this file.
+ *
+ * Copyright (c) 1995-1997 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: @(#) tclUnixNotfy.c 1.42 97/07/02 20:55:44
+ */
+
+#if defined(__CFM68K__) && !defined(__USING_STATIC_LIBS__)
+ #pragma import on
+#endif
+
+#include <unistd.h>
+
+#if defined(__CFM68K__) && !defined(__USING_STATIC_LIBS__)
+ #pragma import reset
+#endif
+
+#include "tclInt.h"
+#include "tclPort.h"
+#include <signal.h>
+
+#ifndef MASK_SIZE
+#define MASK_SIZE howmany(FD_SETSIZE, NFDBITS)
+#endif
+#ifndef SELECT_MASK
+#define SELECT_MASK fd_set
+#endif
+
+/* Prototype (too lazy to create new .h) */
+int Tcl_PollSelectEvent(void);
+
+/*
+ * 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; /* Mask of events that have been seen since the
+ * last time file handlers were invoked for
+ * this file. */
+ 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
+ * select based implementation of the Tcl notifier.
+ */
+
+static struct {
+ FileHandler *firstFileHandlerPtr;
+ /* Pointer to head of file handler list. */
+ fd_mask checkMasks[3*MASK_SIZE];
+ /* This array is used to build up the masks
+ * to be used in the next call to select.
+ * Bits are set in response to calls to
+ * Tcl_CreateFileHandler. */
+ fd_mask readyMasks[3*MASK_SIZE];
+ /* This array reflects the readable/writable
+ * conditions that were found to exist by the
+ * last call to select. */
+ int numFdBits; /* Number of valid bits in checkMasks
+ * (one more than highest fd for which
+ * Tcl_WatchFile has been called). */
+} notifier;
+
+/*
+ * The following static indicates whether this module has been initialized.
+ */
+
+static int initialized = 0;
+
+/*
+ * Static routines defined in this file.
+ */
+
+static void InitNotifier _ANSI_ARGS_((void));
+static void NotifierExitHandler _ANSI_ARGS_((
+ ClientData clientData));
+static int FileHandlerEventProc _ANSI_ARGS_((Tcl_Event *evPtr,
+ int flags));
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * InitNotifier --
+ *
+ * Initializes the notifier state.
+ *
+ * Results:
+ * None.
+ *
+ * Side effects:
+ * Creates a new exit handler.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+InitNotifier()
+{
+ initialized = 1;
+ memset(¬ifier, 0, sizeof(notifier));
+ 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 clientData; /* Not used. */
+{
+ initialized = 0;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_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.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+Tcl_CreateFileHandler(fd, mask, proc, clientData)
+ 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;
+ int index, bit;
+
+ if (!initialized) {
+ InitNotifier();
+ }
+
+ for (filePtr = notifier.firstFileHandlerPtr; filePtr != NULL;
+ filePtr = filePtr->nextPtr) {
+ if (filePtr->fd == fd) {
+ break;
+ }
+ }
+ if (filePtr == NULL) {
+ filePtr = (FileHandler*) ckalloc(sizeof(FileHandler)); /* MLK */
+ filePtr->fd = fd;
+ filePtr->readyMask = 0;
+ filePtr->nextPtr = notifier.firstFileHandlerPtr;
+ notifier.firstFileHandlerPtr = filePtr;
+ }
+ filePtr->proc = proc;
+ filePtr->clientData = clientData;
+ filePtr->mask = mask;
+
+ /*
+ * Update the check masks for this file.
+ */
+
+ index = fd/(NBBY*sizeof(fd_mask));
+ bit = 1 << (fd%(NBBY*sizeof(fd_mask)));
+ if (mask & TCL_READABLE) {
+ notifier.checkMasks[index] |= bit;
+ } else {
+ notifier.checkMasks[index] &= ~bit;
+ }
+ if (mask & TCL_WRITABLE) {
+ (notifier.checkMasks+MASK_SIZE)[index] |= bit;
+ } else {
+ (notifier.checkMasks+MASK_SIZE)[index] &= ~bit;
+ }
+ if (mask & TCL_EXCEPTION) {
+ (notifier.checkMasks+2*(MASK_SIZE))[index] |= bit;
+ } else {
+ (notifier.checkMasks+2*(MASK_SIZE))[index] &= ~bit;
+ }
+ if (notifier.numFdBits <= fd) {
+ notifier.numFdBits = fd+1;
+ }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_DeleteFileHandler --
+ *
+ * Cancel a previously-arranged callback arrangement for
+ * a file.
+ *
+ * Results:
+ * None.
+ *
+ * Side effects:
+ * If a callback was previously registered on file, remove it.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+Tcl_DeleteFileHandler(fd)
+ int fd; /* Stream id for which to remove callback procedure. */
+{
+ FileHandler *filePtr, *prevPtr;
+ int index, bit, mask, i;
+
+ if (!initialized) {
+ InitNotifier();
+ }
+
+ /*
+ * 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;
+ }
+ }
+
+ /*
+ * Update the check masks for this file.
+ */
+
+ index = fd/(NBBY*sizeof(fd_mask));
+ bit = 1 << (fd%(NBBY*sizeof(fd_mask)));
+
+ if (filePtr->mask & TCL_READABLE) {
+ notifier.checkMasks[index] &= ~bit;
+ }
+ if (filePtr->mask & TCL_WRITABLE) {
+ (notifier.checkMasks+MASK_SIZE)[index] &= ~bit;
+ }
+ if (filePtr->mask & TCL_EXCEPTION) {
+ (notifier.checkMasks+2*(MASK_SIZE))[index] &= ~bit;
+ }
+
+ /*
+ * Find current max fd.
+ */
+
+ if (fd+1 == notifier.numFdBits) {
+ for (notifier.numFdBits = 0; index >= 0; index--) {
+ mask = notifier.checkMasks[index]
+ | (notifier.checkMasks+MASK_SIZE)[index]
+ | (notifier.checkMasks+2*(MASK_SIZE))[index];
+ if (mask) {
+ for (i = (NBBY*sizeof(fd_mask)); i > 0; i--) {
+ if (mask & (1 << (i-1))) {
+ break;
+ }
+ }
+ notifier.numFdBits = index * (NBBY*sizeof(fd_mask)) + i;
+ break;
+ }
+ }
+ }
+
+ /*
+ * Clean up information in the callback record.
+ */
+
+ if (prevPtr == NULL) {
+ notifier.firstFileHandlerPtr = filePtr->nextPtr;
+ } else {
+ prevPtr->nextPtr = filePtr->nextPtr;
+ }
+ ckfree((char *) filePtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * 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(evPtr, flags)
+ 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;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_PollSelectEvent --
+ *
+ * This function is called by Tcl_WaitForEvent 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 any event handled, 0 otherwise.
+ *
+ * Side effects:
+ * Queues file events that are detected by the select.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+Tcl_PollSelectEvent(void)
+{
+ FileHandler *filePtr;
+ FileHandlerEvent *fileEvPtr;
+ struct timeval timeout, *timeoutPtr;
+ int bit, index, mask, numFound;
+
+ if (!initialized) {
+ InitNotifier();
+ }
+
+ /*
+ * Set up the timeout structure.
+ */
+
+ timeout.tv_sec = 0;
+ timeout.tv_usec = 0;
+ timeoutPtr = &timeout;
+
+ memcpy((VOID *) notifier.readyMasks, (VOID *) notifier.checkMasks,
+ 3*MASK_SIZE*sizeof(fd_mask));
+ numFound = select(notifier.numFdBits,
+ (SELECT_MASK *) ¬ifier.readyMasks[0],
+ (SELECT_MASK *) ¬ifier.readyMasks[MASK_SIZE],
+ (SELECT_MASK *) ¬ifier.readyMasks[2*MASK_SIZE], timeoutPtr);
+
+ /*
+ * Some systems don't clear the masks after an error, so
+ * we have to do it here.
+ */
+
+ if (numFound == -1) {
+ memset((VOID *) notifier.readyMasks, 0, 3*MASK_SIZE*sizeof(fd_mask));
+ }
+
+ /*
+ * Return if nothing to do.
+ */
+ if ( numFound == 0 )
+ return 0;
+
+ /*
+ * Queue all detected file events before returning.
+ */
+
+ for (filePtr = notifier.firstFileHandlerPtr;
+ (filePtr != NULL) && (numFound > 0);
+ filePtr = filePtr->nextPtr) {
+ index = filePtr->fd / (NBBY*sizeof(fd_mask));
+ bit = 1 << (filePtr->fd % (NBBY*sizeof(fd_mask)));
+ mask = 0;
+
+ if (notifier.readyMasks[index] & bit) {
+ mask |= TCL_READABLE;
+ }
+ if ((notifier.readyMasks+MASK_SIZE)[index] & bit) {
+ mask |= TCL_WRITABLE;
+ }
+ if ((notifier.readyMasks+2*(MASK_SIZE))[index] & bit) {
+ mask |= TCL_EXCEPTION;
+ }
+
+ if (!mask) {
+ continue;
+ } else {
+ numFound--;
+ }
+
+ /*
+ * Don't bother to queue an event if the mask was previously
+ * non-zero since an event must still be on the queue.
+ */
+
+ if (filePtr->readyMask == 0) {
+ fileEvPtr = (FileHandlerEvent *) ckalloc(
+ sizeof(FileHandlerEvent));
+ fileEvPtr->header.proc = FileHandlerEventProc;
+ fileEvPtr->fd = filePtr->fd;
+ Tcl_QueueEvent((Tcl_Event *) fileEvPtr, TCL_QUEUE_TAIL);
+ }
+ filePtr->readyMask = mask;
+ }
+ return 1;
+}