158 lines
5 KiB
C
158 lines
5 KiB
C
/***
|
|
*ftime.c - return system time
|
|
*
|
|
* Copyright (c) 1985-2001, Microsoft Corporation. All rights reserved.
|
|
*
|
|
*Purpose:
|
|
* Returns the system date/time in a structure form.
|
|
*
|
|
*Revision History:
|
|
* 03-??-84 RLB initial version
|
|
* 05-17-86 SKS ported to OS/2
|
|
* 03-09-87 SKS correct Daylight Savings Time flag
|
|
* 11-18-87 SKS Change tzset() to __tzset()
|
|
* 12-11-87 JCR Added "_LOAD_DS" to declaration
|
|
* 10-03-88 JCR 386: Change DOS calls to SYS calls
|
|
* 10-04-88 JCR 386: Removed 'far' keyword
|
|
* 10-10-88 GJF Made API names match DOSCALLS.H
|
|
* 04-12-89 JCR New syscall interface
|
|
* 05-25-89 JCR 386 OS/2 calls use '_syscall' calling convention
|
|
* 03-20-90 GJF Replaced _LOAD_DS with _CALLTYPE1, added #include
|
|
* <cruntime.h>, removed some leftover 16-bit support
|
|
* and fixed the copyright. Also, cleaned up the
|
|
* formatting a bit.
|
|
* 07-25-90 SBM Removed '32' from API names
|
|
* 08-13-90 SBM Compiles cleanly with -W3
|
|
* 08-20-90 SBM Removed old incorrect, redundant tp->dstflag assignment
|
|
* 10-04-90 GJF New-style function declarator.
|
|
* 12-04-90 SRW Changed to include <oscalls.h> instead of <doscalls.h>
|
|
* 12-06-90 SRW Added _CRUISER_ and _WIN32 conditionals.
|
|
* 01-21-91 GJF ANSI naming.
|
|
* 01-23-92 GJF Change in time zone field name for Win32, to support
|
|
* crtdll.dll [_WIN32_].
|
|
* 03-30-93 GJF Revised to use mktime(). Also purged Cruiser support.
|
|
* 04-06-93 SKS Replace _CRTAPI* with __cdecl
|
|
* 04-07-93 SKS Add _CRTIMP keyword for CRT DLL model
|
|
* Restore correct spelling of "timezone" struct member.
|
|
* 07-15-93 GJF Call __tzset() instead of _tzset().
|
|
* 02-10-95 GJF Appended Mac version of source file (somewhat cleaned
|
|
* up), with appropriate #ifdef-s.
|
|
* 01-15-98 GJF Complete rewrite of _ftime to eliminate incorrect dst
|
|
* status during the fall-back hour.
|
|
* 05-17-99 PML Remove all Macintosh support.
|
|
* 10-27-99 GB Remove #inlcude <dostypes.h>
|
|
*
|
|
*******************************************************************************/
|
|
|
|
#ifndef _POSIX_
|
|
|
|
#include <cruntime.h>
|
|
#include <sys/types.h>
|
|
#include <sys/timeb.h>
|
|
#include <time.h>
|
|
#include <msdos.h>
|
|
#include <dos.h>
|
|
#include <stdlib.h>
|
|
#include <windows.h>
|
|
#include <internal.h>
|
|
|
|
/*
|
|
* Number of 100 nanosecond units from 1/1/1601 to 1/1/1970
|
|
*/
|
|
#define EPOCH_BIAS 116444736000000000i64
|
|
|
|
/*
|
|
* Union to facilitate converting from FILETIME to unsigned __int64
|
|
*/
|
|
typedef union {
|
|
unsigned __int64 ft_scalar;
|
|
FILETIME ft_struct;
|
|
} FT;
|
|
|
|
/*
|
|
* Cache for the minutes count for with DST status was last assessed
|
|
*/
|
|
static time_t elapsed_minutes_cache = 0;
|
|
|
|
/*
|
|
* Three values of dstflag_cache
|
|
*/
|
|
#define DAYLIGHT_TIME 1
|
|
#define STANDARD_TIME 0
|
|
#define UNKNOWN_TIME -1
|
|
|
|
/*
|
|
* Cache for the last determined DST status
|
|
*/
|
|
static int dstflag_cache = UNKNOWN_TIME;
|
|
|
|
/***
|
|
*void _ftime(timeptr) - return DOS time in a structure
|
|
*
|
|
*Purpose:
|
|
* returns the current DOS time in a struct timeb structure
|
|
*
|
|
*Entry:
|
|
* struct timeb *timeptr - structure to fill in with time
|
|
*
|
|
*Exit:
|
|
* no return value -- fills in structure
|
|
*
|
|
*Exceptions:
|
|
*
|
|
*******************************************************************************/
|
|
|
|
_CRTIMP void __cdecl _ftime (
|
|
struct _timeb *tp
|
|
)
|
|
{
|
|
FT nt_time;
|
|
time_t t;
|
|
TIME_ZONE_INFORMATION tzinfo;
|
|
DWORD tzstate;
|
|
|
|
__tzset();
|
|
|
|
tp->timezone = (short)(_timezone / 60);
|
|
|
|
GetSystemTimeAsFileTime( &(nt_time.ft_struct) );
|
|
|
|
/*
|
|
* Obtain the current DST status. Note the status is cached and only
|
|
* updated once per minute, if necessary.
|
|
*/
|
|
if ( (t = (time_t)(nt_time.ft_scalar / 600000000i64))
|
|
!= elapsed_minutes_cache )
|
|
{
|
|
if ( (tzstate = GetTimeZoneInformation( &tzinfo )) != 0xFFFFFFFF )
|
|
{
|
|
/*
|
|
* Must be very careful in determining whether or not DST is
|
|
* really in effect.
|
|
*/
|
|
if ( (tzstate == TIME_ZONE_ID_DAYLIGHT) &&
|
|
(tzinfo.DaylightDate.wMonth != 0) &&
|
|
(tzinfo.DaylightBias != 0) )
|
|
dstflag_cache = DAYLIGHT_TIME;
|
|
else
|
|
/*
|
|
* When in doubt, assume standard time
|
|
*/
|
|
dstflag_cache = STANDARD_TIME;
|
|
}
|
|
else
|
|
dstflag_cache = UNKNOWN_TIME;
|
|
|
|
elapsed_minutes_cache = t;
|
|
}
|
|
|
|
tp->dstflag = (short)dstflag_cache;
|
|
|
|
tp->millitm = (unsigned short)((nt_time.ft_scalar / 10000i64) %
|
|
1000i64);
|
|
|
|
tp->time = (time_t)((nt_time.ft_scalar - EPOCH_BIAS) / 10000000i64);
|
|
}
|
|
|
|
#endif /* _POSIX_ */
|