2 * Copyright 2000, International Business Machines Corporation and others.
5 * This software has been released under the terms of the IBM Public
6 * License. For details, see the LICENSE file in the top-level source
7 * directory or online at http://www.openafs.org/dl/license10.html
10 /* Elapsed time package */
11 /* See rx_clock.h for calling conventions */
14 #include "../afs/param.h"
16 #include <afs/param.h>
18 #include <afsconfig.h>
24 #include "../rx/rx_clock.h"
25 #include "../h/types.h"
26 #include "../h/time.h"
28 #include "../afs/sysincludes.h"
29 #include "../afs/afsincludes.h"
30 #include "../rx/rx_clock.h"
40 #if !defined(AFS_USE_GETTIMEOFDAY)
41 /*use this package only if gettimeofday is much much costlier than getitime */
45 #if defined(AFS_GFS_ENV)
46 #define STARTVALUE 8000000 /* Ultrix bounds smaller, too small for general use */
48 #define STARTVALUE 100000000 /* Max number of seconds setitimer allows, for some reason */
51 struct clock clock_now; /* The last elapsed time ready by clock_GetTimer */
53 /* This is set to 1 whenever the time is read, and reset to 0 whenever clock_NewTime is called. This is to allow the caller to control the frequency with which the actual time is re-evaluated (an expensive operation) */
54 int clock_haveCurrentTime;
56 int clock_nUpdates; /* The actual number of clock updates */
57 static int clockInitialized = 0;
59 /* Initialize the clock */
60 void clock_Init(void) {
61 struct itimerval itimer, otimer;
63 if (!clockInitialized) {
64 itimer.it_value.tv_sec = STARTVALUE;
65 itimer.it_value.tv_usec = 0;
66 itimer.it_interval.tv_sec = 0;
67 itimer.it_interval.tv_usec = 0;
69 if (setitimer(ITIMER_REAL, &itimer, &otimer) != 0) {
70 fprintf(stderr, "clock: could not set interval timer; \
71 aborted(errno=%d)\n", errno);
82 /* Make clock uninitialized. */
91 /* Compute the current time. The timer gets the current total elapsed time since startup, expressed in seconds and microseconds. This call is almost 200 usec on an APC RT */
92 void clock_UpdateTime()
94 struct itimerval itimer;
95 getitimer(ITIMER_REAL, &itimer);
96 clock_now.sec = STARTVALUE - 1 - itimer.it_value.tv_sec; /* The "-1" makes up for adding 1000000 usec, on the next line */
97 clock_now.usec = 1000000 - itimer.it_value.tv_usec;
98 if (clock_now.usec == 1000000) clock_now.usec = 0, clock_now.sec++;
99 clock_haveCurrentTime = 1;
105 #endif /* AFS_USE_GETTIMEOFDAY */