Tcl Source Code

Check-in [6554392102]
Login
Bounty program for improvements to Tcl and certain Tcl packages.
Tcl 2019 Conference, Houston/TX, US, Nov 4-8
Send your abstracts to [email protected]
or submit via the online form by Sep 9.

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:[timerate] bug fix: missing scale conversion by Mac OSX on platform where high resolution clicks are not microseconds based; [win] use high resolution timer for the wide clicks and microseconds directly, prevent several forwards/backwards conversions; [win, unix, mac-osx] normalize some functions for common usage in different time units (clicks, micro- and nanoseconds)

# Conflicts: # win/tclWinTime.c

Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | mistake | sebres-trunk-timerate
Files: files | file ages | folders
SHA1: 65543921026335b9cfb0aef4ef6da29d3d375a11
User & Date: sebres 2017-02-07 19:35:51
Context
2017-02-07
19:36
resolve warning: enumeration value ‘TMRT_LAST’ not handled in switch (impossible to handle in sw... Closed-Leaf check-in: 4cb3b2644e user: sebres tags: sebres-trunk-timerate
19:35
[timerate] bug fix: missing scale conversion by Mac OSX on platform where high resolution clicks are... check-in: 6554392102 user: sebres tags: mistake, sebres-trunk-timerate
2017-01-09
19:33
[win] load win-registry library also in development environment (uninstalled) check-in: 0c05a83862 user: sebres tags: sebres-trunk-timerate
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to generic/tclClock.c.

1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
....
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
#ifdef TCL_WIDE_CLICKS
	clicks = TclpGetWideClicks();
#else
	clicks = (Tcl_WideInt) TclpGetClicks();
#endif
	break;
    case CLICKS_MICROS:
	Tcl_GetTime(&now);
	clicks = ((Tcl_WideInt) now.sec * 1000000) + now.usec;
	break;
    }

    Tcl_SetObjResult(interp, Tcl_NewWideIntObj(clicks));
    return TCL_OK;
}
 
................................................................................
int
ClockMicrosecondsObjCmd(
    ClientData clientData,	/* Client data is unused */
    Tcl_Interp *interp,		/* Tcl interpreter */
    int objc,			/* Parameter count */
    Tcl_Obj *const *objv)	/* Parameter values */
{
    Tcl_Time now;

    if (objc != 1) {
	Tcl_WrongNumArgs(interp, 1, objv, NULL);
	return TCL_ERROR;
    }
    Tcl_GetTime(&now);
    Tcl_SetObjResult(interp, Tcl_NewWideIntObj(
	    ((Tcl_WideInt) now.sec * 1000000) + now.usec));
    return TCL_OK;
}
 
/*
 *-----------------------------------------------------------------------------
 *
 * ClockParseformatargsObjCmd --






|
<







 







<
<




<
|
<







1756
1757
1758
1759
1760
1761
1762
1763

1764
1765
1766
1767
1768
1769
1770
....
1826
1827
1828
1829
1830
1831
1832


1833
1834
1835
1836

1837

1838
1839
1840
1841
1842
1843
1844
#ifdef TCL_WIDE_CLICKS
	clicks = TclpGetWideClicks();
#else
	clicks = (Tcl_WideInt) TclpGetClicks();
#endif
	break;
    case CLICKS_MICROS:
	clicks = TclpGetMicroseconds();

	break;
    }

    Tcl_SetObjResult(interp, Tcl_NewWideIntObj(clicks));
    return TCL_OK;
}
 
................................................................................
int
ClockMicrosecondsObjCmd(
    ClientData clientData,	/* Client data is unused */
    Tcl_Interp *interp,		/* Tcl interpreter */
    int objc,			/* Parameter count */
    Tcl_Obj *const *objv)	/* Parameter values */
{


    if (objc != 1) {
	Tcl_WrongNumArgs(interp, 1, objv, NULL);
	return TCL_ERROR;
    }

    Tcl_SetObjResult(interp, Tcl_NewWideIntObj(TclpGetMicroseconds()));

    return TCL_OK;
}
 
/*
 *-----------------------------------------------------------------------------
 *
 * ClockParseformatargsObjCmd --

Changes to generic/tclCmdMZ.c.

4211
4212
4213
4214
4215
4216
4217
4218




4219
4220
4221
4222



4223
4224
4225
4226
4227
4228
4229
4230
4231
4232
4233
4234
....
4242
4243
4244
4245
4246
4247
4248
4249


4250
4251
4252
4253
4254
4255
4256
4257
4258
4259
4260
....
4269
4270
4271
4272
4273
4274
4275





4276
4277
4278
4279
4280
4281
4282
	    return TCL_ERROR;
	}
	codePtr = TclCompileObj(interp, objPtr, NULL, 0);
	TclPreserveByteCode(codePtr);
    }

    /* get start and stop time */
#ifndef TCL_WIDE_CLICKS




    Tcl_GetTime(&now);
    start = now.sec; start *= 1000000; start += now.usec;
#else
    start = TclpGetWideClicks();



#endif

    /* start measurement */
    stop = start + maxms * 1000;
    middle = start;
    while (1) {
    	/* eval single iteration */
    	count++;

	if (!direct) {
	    /* precompiled */
	    rootPtr = TOP_CB(interp);
................................................................................
	    goto done;
	}
	
	/* don't check time up to threshold */
	if (--threshold > 0) continue;

	/* check stop time reached, estimate new threshold */
    #ifndef TCL_WIDE_CLICKS


	Tcl_GetTime(&now);
	middle = now.sec; middle *= 1000000; middle += now.usec;
    #else
	middle = TclpGetWideClicks();
    #endif
	if (middle >= stop) {
	    break;
	}
	/* average iteration time in microsecs */
	threshold = (middle - start) / count;
	if (threshold > maxIterTm) {
................................................................................

    {
	Tcl_Obj *objarr[8], **objs = objarr;
	Tcl_WideInt val;
	const char *fmt;

	middle -= start;		     /* execution time in microsecs */






	/* if not calibrate */
	if (!calibrate) {
	    /* minimize influence of measurement overhead */
	    if (overhead > 0) {
		/* estimate the time of overhead (microsecs) */
		Tcl_WideInt curOverhead = overhead * count;






|
>
>
>
>


<
<
>
>
>



<
<







 







|
>
>


<
<







 







>
>
>
>
>







4211
4212
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222
4223
4224


4225
4226
4227
4228
4229
4230


4231
4232
4233
4234
4235
4236
4237
....
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256


4257
4258
4259
4260
4261
4262
4263
....
4272
4273
4274
4275
4276
4277
4278
4279
4280
4281
4282
4283
4284
4285
4286
4287
4288
4289
4290
	    return TCL_ERROR;
	}
	codePtr = TclCompileObj(interp, objPtr, NULL, 0);
	TclPreserveByteCode(codePtr);
    }

    /* get start and stop time */
#ifdef TCL_WIDE_CLICKS
    start = middle = TclpGetWideClicks();
    /* time to stop execution (in wide clicks) */
    stop = start + (maxms * 1000 / TclpWideClickInMicrosec());
#else
    Tcl_GetTime(&now);
    start = now.sec; start *= 1000000; start += now.usec;


    middle = start;
    /* time to stop execution (in microsecs) */
    stop = start + maxms * 1000;
#endif

    /* start measurement */


    while (1) {
    	/* eval single iteration */
    	count++;

	if (!direct) {
	    /* precompiled */
	    rootPtr = TOP_CB(interp);
................................................................................
	    goto done;
	}
	
	/* don't check time up to threshold */
	if (--threshold > 0) continue;

	/* check stop time reached, estimate new threshold */
    #ifdef TCL_WIDE_CLICKS
	middle = TclpGetWideClicks();
    #else
	Tcl_GetTime(&now);
	middle = now.sec; middle *= 1000000; middle += now.usec;


    #endif
	if (middle >= stop) {
	    break;
	}
	/* average iteration time in microsecs */
	threshold = (middle - start) / count;
	if (threshold > maxIterTm) {
................................................................................

    {
	Tcl_Obj *objarr[8], **objs = objarr;
	Tcl_WideInt val;
	const char *fmt;

	middle -= start;		     /* execution time in microsecs */

    #ifdef TCL_WIDE_CLICKS
	/* convert execution time in wide clicks to microsecs */
	middle *= TclpWideClickInMicrosec();
    #endif

	/* if not calibrate */
	if (!calibrate) {
	    /* minimize influence of measurement overhead */
	    if (overhead > 0) {
		/* estimate the time of overhead (microsecs) */
		Tcl_WideInt curOverhead = overhead * count;

Changes to generic/tclInt.h.

3185
3186
3187
3188
3189
3190
3191









3192







3193
3194
3195
3196
3197
3198
3199
#endif
MODULE_SCOPE void	TclInitThreadStorage(void);
MODULE_SCOPE void	TclFinalizeThreadDataThread(void);
MODULE_SCOPE void	TclFinalizeThreadStorage(void);
#ifdef TCL_WIDE_CLICKS
MODULE_SCOPE Tcl_WideInt TclpGetWideClicks(void);
MODULE_SCOPE double	TclpWideClicksToNanoseconds(Tcl_WideInt clicks);









#endif







MODULE_SCOPE int	TclZlibInit(Tcl_Interp *interp);
MODULE_SCOPE void *	TclpThreadCreateKey(void);
MODULE_SCOPE void	TclpThreadDeleteKey(void *keyPtr);
MODULE_SCOPE void	TclpThreadSetMasterTSD(void *tsdKeyPtr, void *ptr);
MODULE_SCOPE void *	TclpThreadGetMasterTSD(void *tsdKeyPtr);

MODULE_SCOPE void	TclErrorStackResetIf(Tcl_Interp *interp, const char *msg, int length);






>
>
>
>
>
>
>
>
>

>
>
>
>
>
>
>







3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
#endif
MODULE_SCOPE void	TclInitThreadStorage(void);
MODULE_SCOPE void	TclFinalizeThreadDataThread(void);
MODULE_SCOPE void	TclFinalizeThreadStorage(void);
#ifdef TCL_WIDE_CLICKS
MODULE_SCOPE Tcl_WideInt TclpGetWideClicks(void);
MODULE_SCOPE double	TclpWideClicksToNanoseconds(Tcl_WideInt clicks);
MODULE_SCOPE double	TclpWideClickInMicrosec(void);
#else
#   ifdef _WIN32
#	define TCL_WIDE_CLICKS 1
MODULE_SCOPE Tcl_WideInt TclpGetWideClicks(void);
#	define		TclpWideClicksToNanoseconds(clicks) \
				((double)clicks / 1000)
#	define		TclpWideClickInMicrosec() (1)
#   endif
#endif
#ifndef _WIN32
MODULE_SCOPE Tcl_WideInt TclpGetMicroseconds(void);
#else
#    define 		TclpGetMicroseconds() \
				TclpGetWideClicks()
#endif

MODULE_SCOPE int	TclZlibInit(Tcl_Interp *interp);
MODULE_SCOPE void *	TclpThreadCreateKey(void);
MODULE_SCOPE void	TclpThreadDeleteKey(void *keyPtr);
MODULE_SCOPE void	TclpThreadSetMasterTSD(void *tsdKeyPtr, void *ptr);
MODULE_SCOPE void *	TclpThreadGetMasterTSD(void *tsdKeyPtr);

MODULE_SCOPE void	TclErrorStackResetIf(Tcl_Interp *interp, const char *msg, int length);

Changes to unix/tclUnixTime.c.

80
81
82
83
84
85
86


























87
88
89
90
91
92
93
...
212
213
214
215
216
217
218













































219
220
221
222
223
224
225
{
    return time(NULL);
}
 
/*
 *----------------------------------------------------------------------
 *


























 * TclpGetClicks --
 *
 *	This procedure returns a value that represents the highest resolution
 *	clock available on the system. There are no garantees on what the
 *	resolution will be. In Tcl we will call this value a "click". The
 *	start time is also system dependant.
 *
................................................................................
#else
#error Wide high-resolution clicks not implemented on this platform
#endif
    }

    return nsec;
}













































#endif /* TCL_WIDE_CLICKS */
 
/*
 *----------------------------------------------------------------------
 *
 * Tcl_GetTime --
 *






>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>







 







>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>







80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
...
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
{
    return time(NULL);
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclpGetMicroseconds --
 *
 *	This procedure returns the number of microseconds from the epoch.
 *	On most Unix systems the epoch is Midnight Jan 1, 1970 GMT.
 *
 * Results:
 *	Number of microseconds from the epoch.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

Tcl_WideInt
TclpGetMicroseconds(void)
{
    Tcl_Time time;

    tclGetTimeProcPtr(&time, tclTimeClientData);
    return ((Tcl_WideInt)time.sec)*1000000 + time.usec;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclpGetClicks --
 *
 *	This procedure returns a value that represents the highest resolution
 *	clock available on the system. There are no garantees on what the
 *	resolution will be. In Tcl we will call this value a "click". The
 *	start time is also system dependant.
 *
................................................................................
#else
#error Wide high-resolution clicks not implemented on this platform
#endif
    }

    return nsec;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclpWideClickInMicrosec --
 *
 *	This procedure return scale to convert click values from the 
 *	TclpGetWideClicks native resolution to microsecond resolution
 *	and back.
 *
 * Results:
 * 	1 click in microseconds as double.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

double
TclpWideClickInMicrosec(void)
{
    if (tclGetTimeProcPtr != NativeGetTime) {
	return 1.0;
    } else {
#ifdef MAC_OSX_TCL
	static int initialized = 0;
	static double scale = 0.0;

	if (initialized) {
	    return scale;
	} else {
	    mach_timebase_info_data_t tb;

	    mach_timebase_info(&tb);
	    /* value of tb.numer / tb.denom = 1 click in nanoseconds */
	    scale = tb.numer / tb.denom / 1000; /* 1 click in miroseconds */
	    initialized = 1;
	    return scale;
	}
#else
#error Wide high-resolution clicks not implemented on this platform
#endif
    }
}
#endif /* TCL_WIDE_CLICKS */
 
/*
 *----------------------------------------------------------------------
 *
 * Tcl_GetTime --
 *

Changes to win/tclWinTime.c.

119
120
121
122
123
124
125

126
127
128
129
130
131
132
...
150
151
152
153
154
155
156








157
158
159
160

161
162
163
164
165
166
167
...
178
179
180
181
182
183
184








185
186
187
188
189
190
191
192
193

194








































195
196
197
198
199
200
201
202
203
204
...
219
220
221
222
223
224
225









226

227
228
229
230
231
232
233
...
252
253
254
255
256
257
258
259
260
261
262
263
264
265

266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
...
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
...
451
452
453
454
455
456
457
458
459
460
461
462
463
464





































465
466
467


468
469
470

471
472
473
474
475
476
477
static void 		UpdateTimeEachSecond(void);
static void		ResetCounterSamples(Tcl_WideUInt fileTime,
			    Tcl_WideInt perfCounter, Tcl_WideInt perfFreq);
static Tcl_WideInt	AccumulateSample(Tcl_WideInt perfCounter,
			    Tcl_WideUInt fileTime);
static void		NativeScaleTime(Tcl_Time* timebuf,
			    ClientData clientData);

static void		NativeGetTime(Tcl_Time* timebuf,
			    ClientData clientData);

/*
 * TIP #233 (Virtualized Time): Data for the time hooks, if any.
 */

................................................................................
 *
 *----------------------------------------------------------------------
 */

unsigned long
TclpGetSeconds(void)
{








    Tcl_Time t;

    tclGetTimeProcPtr(&t, tclTimeClientData);	/* Tcl_GetTime inlined. */
    return t.sec;

}
 
/*
 *----------------------------------------------------------------------
 *
 * TclpGetClicks --
 *
................................................................................
 *
 *----------------------------------------------------------------------
 */

unsigned long
TclpGetClicks(void)
{








    /*
     * Use the Tcl_GetTime abstraction to get the time in microseconds, as
     * nearly as we can, and return it.
     */

    Tcl_Time now;		/* Current Tcl time */
    unsigned long retval;	/* Value to return */

    tclGetTimeProcPtr(&now, tclTimeClientData);	/* Tcl_GetTime inlined */










































    retval = (now.sec * 1000000) + now.usec;
    return retval;

}
 
/*
 *----------------------------------------------------------------------
 *
 * Tcl_GetTime --
 *
................................................................................
 *----------------------------------------------------------------------
 */

void
Tcl_GetTime(
    Tcl_Time *timePtr)		/* Location to store time information. */
{









    tclGetTimeProcPtr(timePtr, tclTimeClientData);

}
 
/*
 *----------------------------------------------------------------------
 *
 * NativeScaleTime --
 *
................................................................................
     * Native scale is 1:1. Nothing is done.
     */
}
 
/*
 *----------------------------------------------------------------------
 *
 * NativeGetTime --
 *
 *	TIP #233: Gets the current system time in seconds and microseconds
 *	since the beginning of the epoch: 00:00 UCT, January 1, 1970.
 *
 * Results:
 *	Returns the current time in timePtr.

 *
 * Side effects:
 *	On the first call, initializes a set of static variables to keep track
 *	of the base value of the performance counter, the corresponding wall
 *	clock (obtained through ftime) and the frequency of the performance
 *	counter. Also spins a thread whose function is to wake up periodically
 *	and monitor these values, adjusting them as necessary to correct for
 *	drift in the performance counter's oscillator.
 *
 *----------------------------------------------------------------------
 */

static void
NativeGetTime(
    Tcl_Time *timePtr,
    ClientData clientData)
{
    struct _timeb t;

    /*
     * Initialize static storage on the first trip through.
     *
     * Note: Outer check for 'initialized' is a performance win since it
     * avoids an extra mutex lock in the common case.
     */

................................................................................

	/*
	 * If calibration cycle occurred after we get curCounter
	 */
	if (curCounter.QuadPart <= perfCounterLastCall.QuadPart) {
	    usecSincePosixEpoch =
		(fileTimeLastCall.QuadPart - posixEpoch.QuadPart) / 10;
	    timePtr->sec = (long) (usecSincePosixEpoch / 1000000);
	    timePtr->usec = (unsigned long) (usecSincePosixEpoch % 1000000);
	    return;
	}

	/*
	 * If it appears to be more than 1.1 seconds since the last trip
	 * through the calibration loop, the performance counter may have
	 * jumped forward. (See MSDN Knowledge Base article Q274323 for a
	 * description of the hardware problem that makes this test
................................................................................
		11 * curCounterFreq.QuadPart / 10
	) {
	    curFileTime = fileTimeLastCall.QuadPart +
		 ((curCounter.QuadPart - perfCounterLastCall.QuadPart)
		    * 10000000 / curCounterFreq.QuadPart);

	    usecSincePosixEpoch = (curFileTime - posixEpoch.QuadPart) / 10;
	    timePtr->sec = (long) (usecSincePosixEpoch / 1000000);
	    timePtr->usec = (unsigned long) (usecSincePosixEpoch % 1000000);
	    return;
	}
    }

    /*





































     * High resolution timer is not available. Just use ftime.
     */



    _ftime(&t);
    timePtr->sec = (long)t.time;
    timePtr->usec = t.millitm * 1000;

}
 
/*
 *----------------------------------------------------------------------
 *
 * StopCalibration --
 *






>







 







>
>
>
>
>
>
>
>
|

|
|
>







 







>
>
>
>
>
>
>
>
|
|
|
|

|
<

|
>
|
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
|
<
|







 







>
>
>
>
>
>
>
>
>
|
>







 







|

|
|


|
>












|
|
<
<

<
<







 







|
<
<







 







|
<
<




>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
|
|

>
>
|
|
|
>







119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
...
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
...
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208

209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253

254
255
256
257
258
259
260
261
...
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
...
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347


348


349
350
351
352
353
354
355
...
492
493
494
495
496
497
498
499


500
501
502
503
504
505
506
...
513
514
515
516
517
518
519
520


521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
static void 		UpdateTimeEachSecond(void);
static void		ResetCounterSamples(Tcl_WideUInt fileTime,
			    Tcl_WideInt perfCounter, Tcl_WideInt perfFreq);
static Tcl_WideInt	AccumulateSample(Tcl_WideInt perfCounter,
			    Tcl_WideUInt fileTime);
static void		NativeScaleTime(Tcl_Time* timebuf,
			    ClientData clientData);
static Tcl_WideInt	NativeGetMicroseconds(void);
static void		NativeGetTime(Tcl_Time* timebuf,
			    ClientData clientData);

/*
 * TIP #233 (Virtualized Time): Data for the time hooks, if any.
 */

................................................................................
 *
 *----------------------------------------------------------------------
 */

unsigned long
TclpGetSeconds(void)
{
    Tcl_WideInt usecSincePosixEpoch;

    /* Try to use high resolution timer */
    if ( tclGetTimeProcPtr == NativeGetTime
      && (usecSincePosixEpoch = NativeGetMicroseconds())
    ) {
	return usecSincePosixEpoch / 1000000;
    } else {
	Tcl_Time t;

	tclGetTimeProcPtr(&t, tclTimeClientData);	/* Tcl_GetTime inlined. */
	return t.sec;
    }
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclpGetClicks --
 *
................................................................................
 *
 *----------------------------------------------------------------------
 */

unsigned long
TclpGetClicks(void)
{
    Tcl_WideInt usecSincePosixEpoch;

    /* Try to use high resolution timer */
    if ( tclGetTimeProcPtr == NativeGetTime
      && (usecSincePosixEpoch = NativeGetMicroseconds())
    ) {
	return (unsigned long)usecSincePosixEpoch;
    } else {
	/*
	* Use the Tcl_GetTime abstraction to get the time in microseconds, as
	* nearly as we can, and return it.
	*/

	Tcl_Time now;		/* Current Tcl time */


	tclGetTimeProcPtr(&now, tclTimeClientData);	/* Tcl_GetTime inlined */
	return (unsigned long)(now.sec * 1000000) + now.usec;
    }
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclpGetWideClicks --
 *
 *	This procedure returns a WideInt value that represents the highest
 *	resolution clock in microseconds available on the system.
 *
 * Results:
 *	Number of microseconds (from the epoch).
 *
 * Side effects:
 *	This should be used for time-delta resp. for measurement purposes
 *	only, because on some platforms can return microseconds from some
 *	start time (not from the epoch).
 *
 *----------------------------------------------------------------------
 */

Tcl_WideInt
TclpGetWideClicks(void)
{
    Tcl_WideInt usecSincePosixEpoch;

    /* Try to use high resolution timer */
    if ( tclGetTimeProcPtr == NativeGetTime
      && (usecSincePosixEpoch = NativeGetMicroseconds())
    ) {
	return usecSincePosixEpoch;
    } else {
	/*
	* Use the Tcl_GetTime abstraction to get the time in microseconds, as
	* nearly as we can, and return it.
	*/

	Tcl_Time now;

	tclGetTimeProcPtr(&now, tclTimeClientData);	/* Tcl_GetTime inlined */
	return (((Tcl_WideInt)now.sec) * 1000000) + now.usec;

    }
}
 
/*
 *----------------------------------------------------------------------
 *
 * Tcl_GetTime --
 *
................................................................................
 *----------------------------------------------------------------------
 */

void
Tcl_GetTime(
    Tcl_Time *timePtr)		/* Location to store time information. */
{
    Tcl_WideInt usecSincePosixEpoch;

    /* Try to use high resolution timer */
    if ( tclGetTimeProcPtr == NativeGetTime
      && (usecSincePosixEpoch = NativeGetMicroseconds())
    ) {
	timePtr->sec = (long) (usecSincePosixEpoch / 1000000);
	timePtr->usec = (unsigned long) (usecSincePosixEpoch % 1000000);
    } else {
    	tclGetTimeProcPtr(timePtr, tclTimeClientData);
    }
}
 
/*
 *----------------------------------------------------------------------
 *
 * NativeScaleTime --
 *
................................................................................
     * Native scale is 1:1. Nothing is done.
     */
}
 
/*
 *----------------------------------------------------------------------
 *
 * NativeGetMicroseconds --
 *
 *	Gets the current system time in microseconds since the beginning
 *	of the epoch: 00:00 UCT, January 1, 1970.
 *
 * Results:
 *	Returns the wide integer with number of microseconds from the epoch, or
 *	0 if high resolution timer is not available.
 *
 * Side effects:
 *	On the first call, initializes a set of static variables to keep track
 *	of the base value of the performance counter, the corresponding wall
 *	clock (obtained through ftime) and the frequency of the performance
 *	counter. Also spins a thread whose function is to wake up periodically
 *	and monitor these values, adjusting them as necessary to correct for
 *	drift in the performance counter's oscillator.
 *
 *----------------------------------------------------------------------
 */

static Tcl_WideInt
NativeGetMicroseconds(void)


{


    /*
     * Initialize static storage on the first trip through.
     *
     * Note: Outer check for 'initialized' is a performance win since it
     * avoids an extra mutex lock in the common case.
     */

................................................................................

	/*
	 * If calibration cycle occurred after we get curCounter
	 */
	if (curCounter.QuadPart <= perfCounterLastCall.QuadPart) {
	    usecSincePosixEpoch =
		(fileTimeLastCall.QuadPart - posixEpoch.QuadPart) / 10;
	    return usecSincePosixEpoch;


	}

	/*
	 * If it appears to be more than 1.1 seconds since the last trip
	 * through the calibration loop, the performance counter may have
	 * jumped forward. (See MSDN Knowledge Base article Q274323 for a
	 * description of the hardware problem that makes this test
................................................................................
		11 * curCounterFreq.QuadPart / 10
	) {
	    curFileTime = fileTimeLastCall.QuadPart +
		 ((curCounter.QuadPart - perfCounterLastCall.QuadPart)
		    * 10000000 / curCounterFreq.QuadPart);

	    usecSincePosixEpoch = (curFileTime - posixEpoch.QuadPart) / 10;
	    return usecSincePosixEpoch;


	}
    }

    /*
     * High resolution timer is not available.
     */
    return 0;
}
 
/*
 *----------------------------------------------------------------------
 *
 * NativeGetTime --
 *
 *	TIP #233: Gets the current system time in seconds and microseconds
 *	since the beginning of the epoch: 00:00 UCT, January 1, 1970.
 *
 * Results:
 *	Returns the current time in timePtr.
 *
 * Side effects:
 *	See NativeGetMicroseconds for more information.
 *
 *----------------------------------------------------------------------
 */

static void
NativeGetTime(
    Tcl_Time *timePtr,
    ClientData clientData)
{
    Tcl_WideInt usecSincePosixEpoch;

    /*
     * Try to use high resolution timer.
     */
    if ( (usecSincePosixEpoch = NativeGetMicroseconds()) ) {
	timePtr->sec = (long) (usecSincePosixEpoch / 1000000);
	timePtr->usec = (unsigned long) (usecSincePosixEpoch % 1000000);
    } else {
	/*
	* High resolution timer is not available. Just use ftime.
	*/

	struct _timeb t;

	_ftime(&t);
	timePtr->sec = (long)t.time;
	timePtr->usec = t.millitm * 1000;
    }
}
 
/*
 *----------------------------------------------------------------------
 *
 * StopCalibration --
 *