summaryrefslogtreecommitdiffstats
path: root/unix/tclUnixTime.c
blob: 27b6a58c019320f91968deeeb301e3bcab29291a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
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
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
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
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
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
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
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
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
/*
 * tclUnixTime.c --
 *
 *	Contains Unix specific versions of Tcl functions that obtain time
 *	values from the operating system.
 *
 * Copyright (c) 1995 Sun Microsystems, Inc.
 *
 * See the file "license.terms" for information on usage and redistribution of
 * this file, and for a DISCLAIMER OF ALL WARRANTIES.
 */

#include "tclInt.h"
#include <locale.h>
#if defined(TCL_WIDE_CLICKS) && defined(MAC_OSX_TCL)
#include <mach/mach_time.h>
#endif

/*
 * Static functions declared in this file.
 */

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.
 */

Tcl_GetTimeProc *tclGetTimeProcPtr = NativeGetTime;
Tcl_ScaleTimeProc *tclScaleTimeProcPtr = NativeScaleTime;
ClientData tclTimeClientData = NULL;

/*
 *----------------------------------------------------------------------
 *
 * TclpGetSeconds --
 *
 *	This procedure returns the number of seconds from the epoch. On most
 *	Unix systems the epoch is Midnight Jan 1, 1970 GMT.
 *
 * Results:
 *	Number of seconds from the epoch.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

unsigned long
TclpGetSeconds(void)
{
    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.
 *
 * Results:
 *	Number of clicks from some start time.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

unsigned long
TclpGetClicks(void)
{
    unsigned long now;

#ifdef NO_GETTOD
    if (tclGetTimeProcPtr != NativeGetTime) {
	Tcl_Time time;

	tclGetTimeProcPtr(&time, tclTimeClientData);
	now = time.sec*1000000 + time.usec;
    } else {
	/*
	 * A semi-NativeGetTime, specialized to clicks.
	 */
	struct tms dummy;

	now = (unsigned long) times(&dummy);
    }
#else
    Tcl_Time time;

    tclGetTimeProcPtr(&time, tclTimeClientData);
    now = time.sec*1000000 + time.usec;
#endif

    return now;
}
#ifdef TCL_WIDE_CLICKS

/*
 *----------------------------------------------------------------------
 *
 * TclpGetWideClicks --
 *
 *	This procedure returns a WideInt 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.
 *
 * Results:
 *	Number of WideInt clicks from some start time.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

Tcl_WideInt
TclpGetWideClicks(void)
{
    Tcl_WideInt now;

    if (tclGetTimeProcPtr != NativeGetTime) {
	Tcl_Time time;

	tclGetTimeProcPtr(&time, tclTimeClientData);
	now = (Tcl_WideInt) (time.sec*1000000 + time.usec);
    } else {
#ifdef MAC_OSX_TCL
	now = (Tcl_WideInt) (mach_absolute_time() & INT64_MAX);
#else
#error Wide high-resolution clicks not implemented on this platform
#endif
    }

    return now;
}

/*
 *----------------------------------------------------------------------
 *
 * TclpWideClicksToNanoseconds --
 *
 *	This procedure converts click values from the TclpGetWideClicks native
 *	resolution to nanosecond resolution.
 *
 * Results:
 *	Number of nanoseconds from some start time.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

double
TclpWideClicksToNanoseconds(
    Tcl_WideInt clicks)
{
    double nsec;

    if (tclGetTimeProcPtr != NativeGetTime) {
	nsec = clicks * 1000;
    } else {
#ifdef MAC_OSX_TCL
	static mach_timebase_info_data_t tb;
	static uint64_t maxClicksForUInt64;
	
	if (!tb.denom) {
	    mach_timebase_info(&tb);
	    maxClicksForUInt64 = UINT64_MAX / tb.numer;
	}
	if ((uint64_t) clicks < maxClicksForUInt64) {
	    nsec = ((uint64_t) clicks) * tb.numer / tb.denom;
	} else {
	    nsec = ((long double) (uint64_t) clicks) * tb.numer / tb.denom;
	}
#else
#error Wide high-resolution clicks not implemented on this platform
#endif
    }

    return nsec;
}
#endif /* TCL_WIDE_CLICKS */

/*
 *----------------------------------------------------------------------
 *
 * Tcl_GetTime --
 *
 *	Gets the current system time in seconds and microseconds since the
 *	beginning of the epoch: 00:00 UCT, January 1, 1970.
 *
 *	This function is hooked, allowing users to specify their own virtual
 *	system time.
 *
 * Results:
 *	Returns the current time in timePtr.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

void
Tcl_GetTime(
    Tcl_Time *timePtr)		/* Location to store time information. */
{
    tclGetTimeProcPtr(timePtr, tclTimeClientData);
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_SetTimeProc --
 *
 *	TIP #233 (Virtualized Time): Registers two handlers for the
 *	virtualization of Tcl's access to time information.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Remembers the handlers, alters core behaviour.
 *
 *----------------------------------------------------------------------
 */

void
Tcl_SetTimeProc(
    Tcl_GetTimeProc *getProc,
    Tcl_ScaleTimeProc *scaleProc,
    ClientData clientData)
{
    tclGetTimeProcPtr = getProc;
    tclScaleTimeProcPtr = scaleProc;
    tclTimeClientData = clientData;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_QueryTimeProc --
 *
 *	TIP #233 (Virtualized Time): Query which time handlers are registered.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

void
Tcl_QueryTimeProc(
    Tcl_GetTimeProc **getProc,
    Tcl_ScaleTimeProc **scaleProc,
    ClientData *clientData)
{
    if (getProc) {
	*getProc = tclGetTimeProcPtr;
    }
    if (scaleProc) {
	*scaleProc = tclScaleTimeProcPtr;
    }
    if (clientData) {
	*clientData = tclTimeClientData;
    }
}

/*
 *----------------------------------------------------------------------
 *
 * NativeScaleTime --
 *
 *	TIP #233: Scale from virtual time to the real-time. For native scaling
 *	the relationship is 1:1 and nothing has to be done.
 *
 * Results:
 *	Scales the time in timePtr.
 *
 * Side effects:
 *	See above.
 *
 *----------------------------------------------------------------------
 */

static void
NativeScaleTime(
    Tcl_Time *timePtr,
    ClientData clientData)
{
    /* 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:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static void
NativeGetTime(
    Tcl_Time *timePtr,
    ClientData clientData)
{
    struct timeval tv;

    (void) gettimeofday(&tv, NULL);
    timePtr->sec = tv.tv_sec;
    timePtr->usec = tv.tv_usec;
}

/*
 * Local Variables:
 * mode: c
 * c-basic-offset: 4
 * fill-column: 78
 * End:
 */