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/***
*clock.c - Contains the clock runtime
*
* Copyright (c) 1987-1991, Microsoft Corporation. All rights reserved.
*
*Purpose:
* The clock runtime returns the processor time used by
* the current process.
*
*Revision History:
* 01-17-87 JCR Module created
* 06-01-87 SKS "itime" must be declared static
* 07-20-87 JCR Changes "inittime" to "_inittime"
* 12-11-87 JCR Added "_LOAD_DS" to declaration
* 03-20-90 GJF Made calling type _CALLTYPE1, added #include
* <cruntime.h> and fixed the copyright. Also, cleaned
* up the formatting a bit.
* 10-04-90 GJF New-style function declarators.
* 01-22-91 GJF ANSI naming.
* 07-25-91 GJF Added _pinittime definition for new initialization
* scheme [_WIN32_].
* 03-13-92 SKS Changed itime from static local to external as
* a part of return to initializer table scheme.
* Changed _inittime to __inittime.
* 05-19-92 DJM POSIX support.
*
*******************************************************************************/
#include <cruntime.h>
#include <stdio.h>
#include <time.h>
#ifdef _POSIX_
#include <posix/sys/times.h>
#else
#include <sys\timeb.h>
#include <sys\types.h>
#endif /* _POSIX_ */
#ifndef _POSIX_
void __cdecl __inittime(void);
#ifdef _MSC_VER
#pragma data_seg(".CRT$XIC")
static void (__cdecl *pinit)(void) = __inittime;
#pragma data_seg()
#endif /* _MSC_VER */
struct _timeb __itimeb = { 0, 0, 0, 0 };
/***
*clock_t clock() - Return the processor time used by this process.
*
*Purpose:
* This routine calculates how much time the calling process
* has used. At startup time, startup calls __inittime which stores
* the initial time. The clock routine calculates the difference
* between the current time and the initial time.
*
* Clock must reference _cinitime so that _cinitim.asm gets linked in.
* That routine, in turn, puts __inittime in the startup initialization
* routine table.
*
*Entry:
* No parameters.
* itime is a static structure of type timeb.
*
*Exit:
* If successful, clock returns the number of CLK_TCKs (milliseconds)
* that have elapsed. If unsuccessful, clock returns -1.
*
*Exceptions:
* None.
*
*******************************************************************************/
clock_t _CALLTYPE1 clock (
void
)
{
struct _timeb now;
clock_t elapsed;
#ifdef _CRUISER_
extern int _citime;
/* Reference _citime so __inittime gets executed at startup time.*/
_citime=0;
#endif /* _CRUISER_ */
/* Calculate the difference between the initial time and now. */
_ftime(&now);
elapsed = (now.time - __itimeb.time) * CLOCKS_PER_SEC;
elapsed += (int)now.millitm - (int)__itimeb.millitm;
return(elapsed);
}
/***
*void __inittime() - Initialize the time location
*
*Purpose:
* This routine stores the time of the process startup.
* It is only linked in if the user issues a clock runtime call.
*
*Entry:
* No arguments.
*
*Exit:
* No return value.
*
*Exceptions:
* None.
*
*******************************************************************************/
void _CALLTYPE1 __inittime (
void
)
{
_ftime(&__itimeb);
}
#else /* _POSIX_ */
/***
*clock_t clock() - Return the processor time used by this process.
*
*Purpose:
* This routine calculates how much time the calling process
* has used. It uses the POSIX system call times().
*
*
*Entry:
* No parameters.
*
*Exit:
* If successful, clock returns the number of CLK_TCKs (milliseconds)
* that have elapsed. If unsuccessful, clock returns -1.
*
*Exceptions:
* None.
*
*******************************************************************************/
clock_t _CALLTYPE1 clock (
void
)
{
struct tms now;
clock_t elapsed;
elapsed= times(&now);
if (elapsed == (clock_t) -1)
return((clock_t) -1);
else
return(now.tms_utime+now.tms_stime);
}
#endif /* _POSIX_ */
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