/*
* tclTimer.c --
*
* This file provides timer event management facilities for Tcl,
* including the "after" command.
*
* 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.
*
* RCS: @(#) $Id: tclTimer.c,v 1.6 2002/03/01 06:22:31 hobbs Exp $
*/
#include "tkPort.h"
#include "Lang.h"
#ifndef UCHAR
#define UCHAR(x) ((unsigned char) (x))
#endif
/*
* This flag indicates whether this module has been initialized.
*/
static int initialized = 0;
/*
* For each timer callback that's pending there is one record of the following
* type. The normal handlers (created by Tcl_CreateTimerHandler) are chained
* together in a list sorted by time (earliest event first).
*/
typedef struct TimerHandler {
Tcl_Time time; /* When timer is to fire. */
Tcl_TimerProc *proc; /* Procedure to call. */
ClientData clientData; /* Argument to pass to proc. */
Tcl_TimerToken token; /* Identifies handler so it can be
* deleted. */
struct TimerHandler *nextPtr; /* Next event in queue, or NULL for
* end of queue. */
} TimerHandler;
/*
* The data structure below is used by the "after" command to remember
* the command to be executed later. All of the pending "after" commands
* for an interpreter are linked together in a list.
*/
typedef struct AfterInfo {
struct AfterAssocData *assocPtr;
/* Pointer to the "tclAfter" assocData for
* the interp in which command will be
* executed. */
Tcl_Obj *commandPtr; /* Command to execute. */
int id; /* Integer identifier for command; used to
* cancel it. */
Tcl_TimerToken token; /* Used to cancel the "after" command. NULL
* means that the command is run as an
* idle handler rather than as a timer
* handler. NULL means this is an "after
* idle" handler rather than a
* timer handler. */
struct AfterInfo *nextPtr; /* Next in list of all "after" commands for
* this interpreter. */
} AfterInfo;
/*
* One of the following structures is associated with each interpreter
* for which an "after" command has ever been invoked. A pointer to
* this structure is stored in the AssocData for the "tclAfter" key.
*/
typedef struct AfterAssocData {
Tcl_Interp *interp; /* The interpreter for which this data is
* registered. */
AfterInfo *firstAfterPtr; /* First in list of all "after" commands
* still pending for this interpreter, or
* NULL if none. */
} AfterAssocData;
/*
* There is one of the following structures for each of the
* handlers declared in a call to Tcl_DoWhenIdle. All of the
* currently-active handlers are linked together into a list.
*/
typedef struct IdleHandler {
Tcl_IdleProc (*proc); /* Procedure to call. */
ClientData clientData; /* Value to pass to proc. */
int generation; /* Used to distinguish older handlers from
* recently-created ones. */
struct IdleHandler *nextPtr;/* Next in list of active handlers. */
} IdleHandler;
/*
* The timer and idle queues are per-thread because they are associated
* with the notifier, which is also per-thread.
*
* All static variables used in this file are collected into a single
* instance of the following structure. For multi-threaded implementations,
* there is one instance of this structure for each thread.
*
* Notice that different structures with the same name appear in other
* files. The structure defined below is used in this file only.
*/
typedef struct ThreadSpecificData {
TimerHandler *firstTimerHandlerPtr; /* First event in queue. */
int lastTimerId; /* Timer identifier of most recently
* created timer. */
int timerPending; /* 1 if a timer event is in the queue. */
IdleHandler *idleList; /* First in list of all idle handlers. */
IdleHandler *lastIdlePtr; /* Last in list (or NULL for empty list). */
int idleGeneration; /* Used to fill in the "generation" fields
* of IdleHandler structures. Increments
* each time Tcl_DoOneEvent starts calling
* idle handlers, so that all old handlers
* can be called without calling any of the
* new ones created by old ones. */
int afterId; /* For unique identifiers of after events. */
} ThreadSpecificData;
static Tcl_ThreadDataKey dataKey;
/*
* Prototypes for procedures referenced only in this file:
*/
#ifndef TCL_EVENT_IMPLEMENT
static void AfterCleanupProc _ANSI_ARGS_((ClientData clientData,
Tcl_Interp *interp));
static void AfterProc _ANSI_ARGS_((ClientData clientData));
static void FreeAfterPtr _ANSI_ARGS_((AfterInfo *afterPtr));
static AfterInfo * GetAfterEvent _ANSI_ARGS_((AfterAssocData *assocPtr,
Tcl_Obj *commandPtr));
#else
static ThreadSpecificData *InitTimer _ANSI_ARGS_((void));
static void TimerExitProc _ANSI_ARGS_((ClientData clientData));
static int TimerHandlerEventProc _ANSI_ARGS_((Tcl_Event *evPtr,
int flags));
static void TimerCheckProc _ANSI_ARGS_((ClientData clientData,
int flags));
static void TimerSetupProc _ANSI_ARGS_((ClientData clientData,
int flags));
#endif
#ifdef TCL_EVENT_IMPLEMENT
/*
*----------------------------------------------------------------------
*
* InitTimer --
*
* This function initializes the timer module.
*
* Results:
* A pointer to the thread specific data.
*
* Side effects:
* Registers the idle and timer event sources.
*
*----------------------------------------------------------------------
*/
static ThreadSpecificData *
InitTimer()
{
ThreadSpecificData *tsdPtr =
(ThreadSpecificData *) TclThreadDataKeyGet(&dataKey);
if (tsdPtr == NULL) {
tsdPtr = TCL_TSD_INIT(&dataKey);
Tcl_CreateEventSource(TimerSetupProc, TimerCheckProc, NULL);
Tcl_CreateThreadExitHandler(TimerExitProc, NULL);
}
return tsdPtr;
}
void *
TkInitTimer()
{
return InitTimer();
}
/*
*----------------------------------------------------------------------
*
* TimerExitProc --
*
* This function is call at exit or unload time to remove the
* timer and idle event sources.
*
* Results:
* None.
*
* Side effects:
* Removes the timer and idle event sources and remaining events.
*
*----------------------------------------------------------------------
*/
static void
TimerExitProc(clientData)
ClientData clientData; /* Not used. */
{
ThreadSpecificData *tsdPtr =
(ThreadSpecificData *) TclThreadDataKeyGet(&dataKey);
Tcl_DeleteEventSource(TimerSetupProc, TimerCheckProc, NULL);
if (tsdPtr != NULL) {
register TimerHandler *timerHandlerPtr;
timerHandlerPtr = tsdPtr->firstTimerHandlerPtr;
while (timerHandlerPtr != NULL) {
tsdPtr->firstTimerHandlerPtr = timerHandlerPtr->nextPtr;
ckfree((char *) timerHandlerPtr);
timerHandlerPtr = tsdPtr->firstTimerHandlerPtr;
}
}
}
/*
*--------------------------------------------------------------
*
* Tcl_CreateTimerHandler --
*
* Arrange for a given procedure to be invoked at a particular
* time in the future.
*
* Results:
* The return value is a token for the timer event, which
* may be used to delete the event before it fires.
*
* Side effects:
* When milliseconds have elapsed, proc will be invoked
* exactly once.
*
*--------------------------------------------------------------
*/
Tcl_TimerToken
Tcl_CreateTimerHandler(milliseconds, proc, clientData)
int milliseconds; /* How many milliseconds to wait
* before invoking proc. */
Tcl_TimerProc *proc; /* Procedure to invoke. */
ClientData clientData; /* Arbitrary data to pass to proc. */
{
register TimerHandler *timerHandlerPtr, *tPtr2, *prevPtr;
Tcl_Time time;
ThreadSpecificData *tsdPtr;
tsdPtr = InitTimer();
timerHandlerPtr = (TimerHandler *) ckalloc(sizeof(TimerHandler));
/*
* Compute when the event should fire.
*/
Tcl_GetTime(&time);
timerHandlerPtr->time.sec = time.sec + milliseconds/1000;
timerHandlerPtr->time.usec = time.usec + (milliseconds%1000)*1000;
if (timerHandlerPtr->time.usec >= 1000000) {
timerHandlerPtr->time.usec -= 1000000;
timerHandlerPtr->time.sec += 1;
}
/*
* Fill in other fields for the event.
*/
timerHandlerPtr->proc = proc;
timerHandlerPtr->clientData = clientData;
tsdPtr->lastTimerId++;
timerHandlerPtr->token = (Tcl_TimerToken) tsdPtr->lastTimerId;
/*
* Add the event to the queue in the correct position
* (ordered by event firing time).
*/
for (tPtr2 = tsdPtr->firstTimerHandlerPtr, prevPtr = NULL; tPtr2 != NULL;
prevPtr = tPtr2, tPtr2 = tPtr2->nextPtr) {
if ((tPtr2->time.sec > timerHandlerPtr->time.sec)
|| ((tPtr2->time.sec == timerHandlerPtr->time.sec)
&& (tPtr2->time.usec > timerHandlerPtr->time.usec))) {
break;
}
}
timerHandlerPtr->nextPtr = tPtr2;
if (prevPtr == NULL) {
tsdPtr->firstTimerHandlerPtr = timerHandlerPtr;
} else {
prevPtr->nextPtr = timerHandlerPtr;
}
TimerSetupProc(NULL, TCL_ALL_EVENTS);
return timerHandlerPtr->token;
}
/*
*--------------------------------------------------------------
*
* Tcl_DeleteTimerHandler --
*
* Delete a previously-registered timer handler.
*
* Results:
* None.
*
* Side effects:
* Destroy the timer callback identified by TimerToken,
* so that its associated procedure will not be called.
* If the callback has already fired, or if the given
* token doesn't exist, then nothing happens.
*
*--------------------------------------------------------------
*/
void
Tcl_DeleteTimerHandler(token)
Tcl_TimerToken token; /* Result previously returned by
* Tcl_DeleteTimerHandler. */
{
register TimerHandler *timerHandlerPtr, *prevPtr;
ThreadSpecificData *tsdPtr;
tsdPtr = InitTimer();
for (timerHandlerPtr = tsdPtr->firstTimerHandlerPtr, prevPtr = NULL;
timerHandlerPtr != NULL; prevPtr = timerHandlerPtr,
timerHandlerPtr = timerHandlerPtr->nextPtr) {
if (timerHandlerPtr->token != token) {
continue;
}
if (prevPtr == NULL) {
tsdPtr->firstTimerHandlerPtr = timerHandlerPtr->nextPtr;
} else {
prevPtr->nextPtr = timerHandlerPtr->nextPtr;
}
ckfree((char *) timerHandlerPtr);
return;
}
}
/*
*----------------------------------------------------------------------
*
* TimerSetupProc --
*
* This function is called by Tcl_DoOneEvent to setup the timer
* event source for before blocking. This routine checks both the
* idle and after timer lists.
*
* Results:
* None.
*
* Side effects:
* May update the maximum notifier block time.
*
*----------------------------------------------------------------------
*/
static void
TimerSetupProc(data, flags)
ClientData data; /* Not used. */
int flags; /* Event flags as passed to Tcl_DoOneEvent. */
{
Tcl_Time blockTime;
ThreadSpecificData *tsdPtr = InitTimer();
if (((flags & TCL_IDLE_EVENTS) && tsdPtr->idleList)
|| ((flags & TCL_TIMER_EVENTS) && tsdPtr->timerPending)) {
/*
* There is an idle handler or a pending timer event, so just poll.
*/
blockTime.sec = 0;
blockTime.usec = 0;
} else if ((flags & TCL_TIMER_EVENTS) && tsdPtr->firstTimerHandlerPtr) {
/*
* Compute the timeout for the next timer on the list.
*/
Tcl_GetTime(&blockTime);
blockTime.sec = tsdPtr->firstTimerHandlerPtr->time.sec - blockTime.sec;
blockTime.usec = tsdPtr->firstTimerHandlerPtr->time.usec -
blockTime.usec;
if (blockTime.usec < 0) {
blockTime.sec -= 1;
blockTime.usec += 1000000;
}
if (blockTime.sec < 0) {
blockTime.sec = 0;
blockTime.usec = 0;
}
} else {
return;
}
Tcl_SetMaxBlockTime(&blockTime);
}
/*
*----------------------------------------------------------------------
*
* TimerCheckProc --
*
* This function is called by Tcl_DoOneEvent to check the timer
* event source for events. This routine checks both the
* idle and after timer lists.
*
* Results:
* None.
*
* Side effects:
* May queue an event and update the maximum notifier block time.
*
*----------------------------------------------------------------------
*/
static void
TimerCheckProc(data, flags)
ClientData data; /* Not used. */
int flags; /* Event flags as passed to Tcl_DoOneEvent. */
{
Tcl_Event *timerEvPtr;
Tcl_Time blockTime;
ThreadSpecificData *tsdPtr = InitTimer();
if ((flags & TCL_TIMER_EVENTS) && tsdPtr->firstTimerHandlerPtr) {
/*
* Compute the timeout for the next timer on the list.
*/
Tcl_GetTime(&blockTime);
blockTime.sec = tsdPtr->firstTimerHandlerPtr->time.sec - blockTime.sec;
blockTime.usec = tsdPtr->firstTimerHandlerPtr->time.usec -
blockTime.usec;
if (blockTime.usec < 0) {
blockTime.sec -= 1;
blockTime.usec += 1000000;
}
if (blockTime.sec < 0) {
blockTime.sec = 0;
blockTime.usec = 0;
}
/*
* If the first timer has expired, stick an event on the queue.
*/
if (blockTime.sec == 0 && blockTime.usec == 0 &&
!tsdPtr->timerPending) {
tsdPtr->timerPending = 1;
timerEvPtr = (Tcl_Event *) ckalloc(sizeof(Tcl_Event));
timerEvPtr->proc = TimerHandlerEventProc;
Tcl_QueueEvent(timerEvPtr, TCL_QUEUE_TAIL);
}
}
}
/*
*----------------------------------------------------------------------
*
* TimerHandlerEventProc --
*
* This procedure is called by Tcl_ServiceEvent when a timer event
* reaches the front of the event queue. This procedure handles
* the event by invoking the callbacks for all timers that are
* ready.
*
* 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_TIMER_EVENTS flag bit isn't set.
*
* Side effects:
* Whatever the timer handler callback procedures do.
*
*----------------------------------------------------------------------
*/
static int
TimerHandlerEventProc(evPtr, flags)
Tcl_Event *evPtr; /* Event to service. */
int flags; /* Flags that indicate what events to
* handle, such as TCL_FILE_EVENTS. */
{
TimerHandler *timerHandlerPtr, **nextPtrPtr;
Tcl_Time time;
int currentTimerId;
ThreadSpecificData *tsdPtr = InitTimer();
/*
* Do nothing if timers aren't enabled. This leaves the event on the
* queue, so we will get to it as soon as ServiceEvents() is called
* with timers enabled.
*/
if (!(flags & TCL_TIMER_EVENTS)) {
return 0;
}
/*
* The code below is trickier than it may look, for the following
* reasons:
*
* 1. New handlers can get added to the list while the current
* one is being processed. If new ones get added, we don't
* want to process them during this pass through the list to avoid
* starving other event sources. This is implemented using the
* token number in the handler: new handlers will have a
* newer token than any of the ones currently on the list.
* 2. The handler can call Tcl_DoOneEvent, so we have to remove
* the handler from the list before calling it. Otherwise an
* infinite loop could result.
* 3. Tcl_DeleteTimerHandler can be called to remove an element from
* the list while a handler is executing, so the list could
* change structure during the call.
* 4. Because we only fetch the current time before entering the loop,
* the only way a new timer will even be considered runnable is if
* its expiration time is within the same millisecond as the
* current time. This is fairly likely on Windows, since it has
* a course granularity clock. Since timers are placed
* on the queue in time order with the most recently created
* handler appearing after earlier ones with the same expiration
* time, we don't have to worry about newer generation timers
* appearing before later ones.
*/
tsdPtr->timerPending = 0;
currentTimerId = tsdPtr->lastTimerId;
Tcl_GetTime(&time);
while (1) {
nextPtrPtr = &tsdPtr->firstTimerHandlerPtr;
timerHandlerPtr = tsdPtr->firstTimerHandlerPtr;
if (timerHandlerPtr == NULL) {
break;
}
if ((timerHandlerPtr->time.sec > time.sec)
|| ((timerHandlerPtr->time.sec == time.sec)
&& (timerHandlerPtr->time.usec > time.usec))) {
break;
}
/*
* Bail out if the next timer is of a newer generation.
*/
if ((currentTimerId - (int)timerHandlerPtr->token) < 0) {
break;
}
/*
* Remove the handler from the queue before invoking it,
* to avoid potential reentrancy problems.
*/
(*nextPtrPtr) = timerHandlerPtr->nextPtr;
(*timerHandlerPtr->proc)(timerHandlerPtr->clientData);
ckfree((char *) timerHandlerPtr);
}
TimerSetupProc(NULL, TCL_TIMER_EVENTS);
return 1;
}
/*
*--------------------------------------------------------------
*
* Tcl_DoWhenIdle --
*
* Arrange for proc to be invoked the next time the system is
* idle (i.e., just before the next time that Tcl_DoOneEvent
* would have to wait for something to happen).
*
* Results:
* None.
*
* Side effects:
* Proc will eventually be called, with clientData as argument.
* See the manual entry for details.
*
*--------------------------------------------------------------
*/
void
Tcl_DoWhenIdle(proc, clientData)
Tcl_IdleProc *proc; /* Procedure to invoke. */
ClientData clientData; /* Arbitrary value to pass to proc. */
{
register IdleHandler *idlePtr;
Tcl_Time blockTime;
ThreadSpecificData *tsdPtr = InitTimer();
idlePtr = (IdleHandler *) ckalloc(sizeof(IdleHandler));
idlePtr->proc = proc;
idlePtr->clientData = clientData;
idlePtr->generation = tsdPtr->idleGeneration;
idlePtr->nextPtr = NULL;
if (tsdPtr->lastIdlePtr == NULL) {
tsdPtr->idleList = idlePtr;
} else {
tsdPtr->lastIdlePtr->nextPtr = idlePtr;
}
tsdPtr->lastIdlePtr = idlePtr;
blockTime.sec = 0;
blockTime.usec = 0;
Tcl_SetMaxBlockTime(&blockTime);
}
/*
*----------------------------------------------------------------------
*
* Tcl_CancelIdleCall --
*
* If there are any when-idle calls requested to a given procedure
* with given clientData, cancel all of them.
*
* Results:
* None.
*
* Side effects:
* If the proc/clientData combination were on the when-idle list,
* they are removed so that they will never be called.
*
*----------------------------------------------------------------------
*/
void
Tcl_CancelIdleCall(proc, clientData)
Tcl_IdleProc *proc; /* Procedure that was previously registered. */
ClientData clientData; /* Arbitrary value to pass to proc. */
{
register IdleHandler *idlePtr, *prevPtr;
IdleHandler *nextPtr;
ThreadSpecificData *tsdPtr = InitTimer();
for (prevPtr = NULL, idlePtr = tsdPtr->idleList; idlePtr != NULL;
prevPtr = idlePtr, idlePtr = idlePtr->nextPtr) {
while ((idlePtr->proc == proc)
&& (idlePtr->clientData == clientData)) {
nextPtr = idlePtr->nextPtr;
ckfree((char *) idlePtr);
idlePtr = nextPtr;
if (prevPtr == NULL) {
tsdPtr->idleList = idlePtr;
} else {
prevPtr->nextPtr = idlePtr;
}
if (idlePtr == NULL) {
tsdPtr->lastIdlePtr = prevPtr;
return;
}
}
}
}
/*
*----------------------------------------------------------------------
*
* TclServiceIdle --
*
* This procedure is invoked by the notifier when it becomes
* idle. It will invoke all idle handlers that are present at
* the time the call is invoked, but not those added during idle
* processing.
*
* Results:
* The return value is 1 if TclServiceIdle found something to
* do, otherwise return value is 0.
*
* Side effects:
* Invokes all pending idle handlers.
*
*----------------------------------------------------------------------
*/
int
TclServiceIdle()
{
IdleHandler *idlePtr;
int oldGeneration;
Tcl_Time blockTime;
ThreadSpecificData *tsdPtr = InitTimer();
if (tsdPtr->idleList == NULL) {
return 0;
}
oldGeneration = tsdPtr->idleGeneration;
tsdPtr->idleGeneration++;
/*
* The code below is trickier than it may look, for the following
* reasons:
*
* 1. New handlers can get added to the list while the current
* one is being processed. If new ones get added, we don't
* want to process them during this pass through the list (want
* to check for other work to do first). This is implemented
* using the generation number in the handler: new handlers
* will have a different generation than any of the ones currently
* on the list.
* 2. The handler can call Tcl_DoOneEvent, so we have to remove
* the handler from the list before calling it. Otherwise an
* infinite loop could result.
* 3. Tcl_CancelIdleCall can be called to remove an element from
* the list while a handler is executing, so the list could
* change structure during the call.
*/
for (idlePtr = tsdPtr->idleList;
((idlePtr != NULL)
&& ((oldGeneration - idlePtr->generation) >= 0));
idlePtr = tsdPtr->idleList) {
tsdPtr->idleList = idlePtr->nextPtr;
if (tsdPtr->idleList == NULL) {
tsdPtr->lastIdlePtr = NULL;
}
(*idlePtr->proc)(idlePtr->clientData);
ckfree((char *) idlePtr);
}
if (tsdPtr->idleList) {
blockTime.sec = 0;
blockTime.usec = 0;
Tcl_SetMaxBlockTime(&blockTime);
}
return 1;
}
#endif
#ifndef TCL_EVENT_IMPLEMENT
/*
*----------------------------------------------------------------------
*
* Tcl_AfterObjCmd --
*
* This procedure is invoked to process the "after" Tcl command.
* See the user documentation for details on what it does.
*
* Results:
* A standard Tcl result.
*
* Side effects:
* See the user documentation.
*
*----------------------------------------------------------------------
*/
#if ((defined(__STDC__) || defined(SABER)) && !defined(NO_PROTOTYPE)) || defined(__cplusplus) || defined(USE_PROTOTYPE)
# define ICONST const
#else
# define ICONST
#endif
/* ARGSUSED */
int
Tcl_AfterObjCmd(clientData, interp, objc, objv)
ClientData clientData; /* Points to the "tclAfter" assocData for
* this interpreter, or NULL if the assocData
* hasn't been created yet.*/
Tcl_Interp *interp; /* Current interpreter. */
int objc; /* Number of arguments. */
Tcl_Obj *ICONST objv[]; /* Argument objects. */
{
int ms;
AfterInfo *afterPtr;
AfterAssocData *assocPtr = (AfterAssocData *) clientData;
Tcl_CmdInfo cmdInfo;
int length;
char *argString;
int index;
char buf[16 + TCL_INTEGER_SPACE];
static CONST char *afterSubCmds[] = {
"cancel", "idle", "info", (char *) NULL
};
enum afterSubCmds {AFTER_CANCEL, AFTER_IDLE, AFTER_INFO};
ThreadSpecificData *tsdPtr = TkInitTimer();
if (objc < 2) {
Tcl_WrongNumArgs(interp, 1, (Tcl_Obj **)objv, "option ?arg arg ...?");
return TCL_ERROR;
}
/*
* Create the "after" information associated for this interpreter,
* if it doesn't already exist. Associate it with the command too,
* so that it will be passed in as the ClientData argument in the
* future.
*/
if (assocPtr == NULL) {
assocPtr = (AfterAssocData *) ckalloc(sizeof(AfterAssocData));
assocPtr->interp = interp;
assocPtr->firstAfterPtr = NULL;
Tcl_SetAssocData(interp, "tclAfter", AfterCleanupProc,
(ClientData) assocPtr);
cmdInfo.proc = NULL;
cmdInfo.clientData = (ClientData) NULL;
cmdInfo.objProc = (Tcl_ObjCmdProc *) Tcl_AfterObjCmd;
cmdInfo.objClientData = (ClientData) assocPtr;
cmdInfo.deleteProc = NULL;
cmdInfo.deleteData = (ClientData) assocPtr;
Tcl_SetCommandInfo(interp, Tcl_GetStringFromObj(objv[0], &length),
&cmdInfo);
}
/*
* First lets see if the command was passed a number as the first argument.
*/
if (TclObjGetType(objv[1]) == &tclIntType) {
ms = (int) TclObjInternal(objv[1])->longValue;
goto processInteger;
}
argString = Tcl_GetStringFromObj(objv[1], &length);
if (isdigit(UCHAR(argString[0]))) { /* INTL: digit */
if (Tcl_GetIntFromObj(interp, objv[1], &ms) != TCL_OK) {
return TCL_ERROR;
}
processInteger:
if (ms < 0) {
ms = 0;
}
if (objc == 2) {
Tcl_Sleep(ms);
return TCL_OK;
}
afterPtr = (AfterInfo *) ckalloc((unsigned) (sizeof(AfterInfo)));
afterPtr->assocPtr = assocPtr;
if (objc == 3) {
afterPtr->commandPtr = LangMakeCallback(objv[2]);
} else {
Tcl_Obj *objPtr = Tcl_ConcatObj(objc-2, (Tcl_Obj **)objv+2);
afterPtr->commandPtr = LangMakeCallback(objPtr);
Tcl_DecrRefCount(objPtr);
}
/*
* The variable below is used to generate unique identifiers for
* after commands. This id can wrap around, which can potentially
* cause problems. However, there are not likely to be problems
* in practice, because after commands can only be requested to
* about a month in the future, and wrap-around is unlikely to
* occur in less than about 1-10 years. Thus it's unlikely that
* any old ids will still be around when wrap-around occurs.
*/
afterPtr->id = tsdPtr->afterId;
tsdPtr->afterId += 1;
afterPtr->token = Tcl_CreateTimerHandler(ms, AfterProc,
(ClientData) afterPtr);
afterPtr->nextPtr = assocPtr->firstAfterPtr;
assocPtr->firstAfterPtr = afterPtr;
sprintf(buf, "after#%d", afterPtr->id);
Tcl_AppendResult(interp, buf, (char *) NULL);
return TCL_OK;
}
/*
* If it's not a number it must be a subcommand.
*/
if (Tcl_GetIndexFromObj(NULL, objv[1], afterSubCmds, "argument",
0, &index) != TCL_OK) {
Tcl_AppendResult(interp, "bad argument \"", argString,
"\": must be cancel, idle, info, or a number",
(char *) NULL);
return TCL_ERROR;
}
switch ((enum afterSubCmds) index) {
case AFTER_CANCEL: {
Tcl_Obj *commandPtr;
char *command, *tempCommand;
int tempLength;
if (objc < 3) {
Tcl_WrongNumArgs(interp, 2, (Tcl_Obj **)objv, "id|command");
return TCL_ERROR;
}
if (objc == 3) {
commandPtr = objv[2];
afterPtr = GetAfterEvent(assocPtr, commandPtr);
if (afterPtr != NULL) {
goto got_after;
}
} else {
commandPtr = Tcl_ConcatObj(objc-2, (Tcl_Obj **)objv+2);;
}
command = Tcl_GetStringFromObj(commandPtr, &length);
for (afterPtr = assocPtr->firstAfterPtr; afterPtr != NULL;
afterPtr = afterPtr->nextPtr) {
tempCommand = Tcl_GetStringFromObj(afterPtr->commandPtr,
&tempLength);
if ((length == tempLength)
&& (memcmp((void*) command, (void*) tempCommand,
(unsigned) length) == 0)) {
break;
}
}
if (afterPtr == NULL) {
afterPtr = GetAfterEvent(assocPtr, commandPtr);
}
if (objc != 3) {
Tcl_DecrRefCount(commandPtr);
}
got_after:
if (afterPtr != NULL) {
if (afterPtr->token != NULL) {
Tcl_DeleteTimerHandler(afterPtr->token);
} else {
Tcl_CancelIdleCall(AfterProc, (ClientData) afterPtr);
}
FreeAfterPtr(afterPtr);
}
break;
}
case AFTER_IDLE:
if (objc < 3) {
Tcl_WrongNumArgs(interp, 2, (Tcl_Obj **)objv, "script script ...");
return TCL_ERROR;
}
afterPtr = (AfterInfo *) ckalloc((unsigned) (sizeof(AfterInfo)));
afterPtr->assocPtr = assocPtr;
if (objc == 3) {
afterPtr->commandPtr = LangMakeCallback(objv[2]);
} else {
Tcl_Obj *objPtr = Tcl_ConcatObj(objc-2, (Tcl_Obj **)objv+2);
afterPtr->commandPtr = LangMakeCallback(objPtr);
Tcl_DecrRefCount(objPtr);
}
#ifndef _LANG
/* commandPtr already has refcnt==1 */
Tcl_IncrRefCount(afterPtr->commandPtr);
#endif
afterPtr->id = tsdPtr->afterId;
tsdPtr->afterId += 1;
afterPtr->token = NULL;
afterPtr->nextPtr = assocPtr->firstAfterPtr;
assocPtr->firstAfterPtr = afterPtr;
Tcl_DoWhenIdle(AfterProc, (ClientData) afterPtr);
sprintf(buf, "after#%d", afterPtr->id);
Tcl_AppendResult(interp, buf, (char *) NULL);
break;
case AFTER_INFO: {
Tcl_Obj *resultListPtr;
if (objc == 2) {
for (afterPtr = assocPtr->firstAfterPtr; afterPtr != NULL;
afterPtr = afterPtr->nextPtr) {
if (assocPtr->interp == interp) {
sprintf(buf, "after#%d", afterPtr->id);
Tcl_AppendElement(interp, buf);
}
}
return TCL_OK;
}
if (objc != 3) {
Tcl_WrongNumArgs(interp, 2, (Tcl_Obj **)objv, "?id?");
return TCL_ERROR;
}
afterPtr = GetAfterEvent(assocPtr, objv[2]);
if (afterPtr == NULL) {
Tcl_AppendResult(interp, "event \"", Tcl_GetString(objv[2]),
"\" doesn't exist", (char *) NULL);
return TCL_ERROR;
}
resultListPtr = Tcl_GetObjResult(interp);
Tcl_ListObjAppendElement(interp, resultListPtr, LangCallbackObj(afterPtr->commandPtr));
Tcl_ListObjAppendElement(interp, resultListPtr, Tcl_NewStringObj(
(afterPtr->token == NULL) ? "idle" : "timer", -1));
Tcl_SetObjResult(interp, resultListPtr);
break;
}
default: {
panic("Tcl_AfterObjCmd: bad subcommand index to afterSubCmds");
}
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* GetAfterEvent --
*
* This procedure parses an "after" id such as "after#4" and
* returns a pointer to the AfterInfo structure.
*
* Results:
* The return value is either a pointer to an AfterInfo structure,
* if one is found that corresponds to "cmdString" and is for interp,
* or NULL if no corresponding after event can be found.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static AfterInfo *
GetAfterEvent(assocPtr, commandPtr)
AfterAssocData *assocPtr; /* Points to "after"-related information for
* this interpreter. */
Tcl_Obj *commandPtr;
{
char *cmdString; /* Textual identifier for after event, such
* as "after#6". */
AfterInfo *afterPtr;
int id;
char *end;
cmdString = Tcl_GetString(commandPtr);
if (strncmp(cmdString, "after#", 6) != 0) {
return NULL;
}
cmdString += 6;
id = strtoul(cmdString, &end, 10);
if ((end == cmdString) || (*end != 0)) {
return NULL;
}
for (afterPtr = assocPtr->firstAfterPtr; afterPtr != NULL;
afterPtr = afterPtr->nextPtr) {
if (afterPtr->id == id) {
return afterPtr;
}
}
return NULL;
}
/*
*----------------------------------------------------------------------
*
* AfterProc --
*
* Timer callback to execute commands registered with the
* "after" command.
*
* Results:
* None.
*
* Side effects:
* Executes whatever command was specified. If the command
* returns an error, then the command "bgerror" is invoked
* to process the error; if bgerror fails then information
* about the error is output on stderr.
*
*----------------------------------------------------------------------
*/
static void
AfterProc(clientData)
ClientData clientData; /* Describes command to execute. */
{
AfterInfo *afterPtr = (AfterInfo *) clientData;
AfterAssocData *assocPtr = afterPtr->assocPtr;
AfterInfo *prevPtr;
int result;
Tcl_Interp *interp;
char *script;
int numBytes;
/*
* First remove the callback from our list of callbacks; otherwise
* someone could delete the callback while it's being executed, which
* could cause a core dump.
*/
if (assocPtr->firstAfterPtr == afterPtr) {
assocPtr->firstAfterPtr = afterPtr->nextPtr;
} else {
for (prevPtr = assocPtr->firstAfterPtr; prevPtr->nextPtr != afterPtr;
prevPtr = prevPtr->nextPtr) {
/* Empty loop body. */
}
prevPtr->nextPtr = afterPtr->nextPtr;
}
/*
* Execute the callback.
*/
interp = assocPtr->interp;
Tcl_Preserve((ClientData) interp);
result = LangDoCallback(interp, afterPtr->commandPtr, 0, 0);
if (result != TCL_OK) {
Tcl_AddErrorInfo(interp, "\n (\"after\" script)");
Tcl_BackgroundError(interp);
}
Tcl_Release((ClientData) interp);
/*
* Free the memory for the callback.
*/
Tcl_DecrRefCount(afterPtr->commandPtr);
ckfree((char *) afterPtr);
}
/*
*----------------------------------------------------------------------
*
* FreeAfterPtr --
*
* This procedure removes an "after" command from the list of
* those that are pending and frees its resources. This procedure
* does *not* cancel the timer handler; if that's needed, the
* caller must do it.
*
* Results:
* None.
*
* Side effects:
* The memory associated with afterPtr is released.
*
*----------------------------------------------------------------------
*/
static void
FreeAfterPtr(afterPtr)
AfterInfo *afterPtr; /* Command to be deleted. */
{
AfterInfo *prevPtr;
AfterAssocData *assocPtr = afterPtr->assocPtr;
if (assocPtr->firstAfterPtr == afterPtr) {
assocPtr->firstAfterPtr = afterPtr->nextPtr;
} else {
for (prevPtr = assocPtr->firstAfterPtr; prevPtr->nextPtr != afterPtr;
prevPtr = prevPtr->nextPtr) {
/* Empty loop body. */
}
prevPtr->nextPtr = afterPtr->nextPtr;
}
Tcl_DecrRefCount(afterPtr->commandPtr);
ckfree((char *) afterPtr);
}
/*
*----------------------------------------------------------------------
*
* AfterCleanupProc --
*
* This procedure is invoked whenever an interpreter is deleted
* to cleanup the AssocData for "tclAfter".
*
* Results:
* None.
*
* Side effects:
* After commands are removed.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
static void
AfterCleanupProc(clientData, interp)
ClientData clientData; /* Points to AfterAssocData for the
* interpreter. */
Tcl_Interp *interp; /* Interpreter that is being deleted. */
{
AfterAssocData *assocPtr = (AfterAssocData *) clientData;
AfterInfo *afterPtr;
while (assocPtr->firstAfterPtr != NULL) {
afterPtr = assocPtr->firstAfterPtr;
assocPtr->firstAfterPtr = afterPtr->nextPtr;
if (afterPtr->token != NULL) {
Tcl_DeleteTimerHandler(afterPtr->token);
} else {
Tcl_CancelIdleCall(AfterProc, (ClientData) afterPtr);
}
Tcl_DecrRefCount(afterPtr->commandPtr);
ckfree((char *) afterPtr);
}
ckfree((char *) assocPtr);
}
#endif