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/* Copyright (C) 2004 MySQL AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/*
TODO: in functions my_micro_time() and my_micro_time_and_time() there
exists some common code that should be merged into a function.
*/
#include "mysys_priv.h"
#include "my_static.h"
#ifdef __NETWARE__
#include <nks/time.h>
#elif defined(__WIN__)
static ulonglong query_performance_frequency, query_performance_offset;
#define OFFSET_TO_EPOC 116444736000000000LL
#elif defined(HAVE_GETHRTIME)
static ulonglong gethrtime_offset;
#endif
/*
get time since epoc in 100 nanosec units
NOTE:
Thus to get the current time we should use the system function
with the highest possible resolution
The value is not subject to resetting or drifting by way of adjtime() or
settimeofday(), and thus it is *NOT* appropriate for getting the current
timestamp. It can be used for calculating time intervals, though.
And it's good enough for UUID.
*/
ulonglong my_getsystime()
{
#ifdef HAVE_CLOCK_GETTIME
struct timespec tp;
clock_gettime(CLOCK_REALTIME, &tp);
return (ulonglong)tp.tv_sec*10000000+(ulonglong)tp.tv_nsec/100;
#elif defined(HAVE_GETHRTIME)
return gethrtime()/100-gethrtime_offset;
#elif defined(__WIN__)
LARGE_INTEGER t_cnt;
if (query_performance_frequency)
{
QueryPerformanceCounter(&t_cnt);
return ((t_cnt.QuadPart / query_performance_frequency * 10000000) +
((t_cnt.QuadPart % query_performance_frequency) * 10000000 /
query_performance_frequency) + query_performance_offset);
}
return 0;
#elif defined(__NETWARE__)
NXTime_t tm;
NXGetTime(NX_SINCE_1970, NX_NSECONDS, &tm);
return (ulonglong)tm/100;
#else
/* TODO: check for other possibilities for hi-res timestamping */
struct timeval tv;
gettimeofday(&tv,NULL);
return (ulonglong)tv.tv_sec*10000000+(ulonglong)tv.tv_usec*10;
#endif
}
/* Return current time in microseconds since epoch */
my_hrtime_t my_hrtime()
{
my_hrtime_t hrtime;
#if defined(__WIN__)
ulonglong newtime;
GetSystemTimeAsFileTime((FILETIME*)&newtime);
newtime -= OFFSET_TO_EPOC;
hrtime.val= newtime/10;
#elif defined(HAVE_GETHRTIME)
struct timeval t;
/*
The following loop is here because gettimeofday may fail on some systems
*/
while (gettimeofday(&t, NULL) != 0)
{}
hrtime.val= t.tv_sec*1000000 + t.tv_usec;
#else
hrtime.val= my_getsystime()/10;
#endif
return hrtime;
}
/*
This function is basically equivalent to
*interval= my_getsystime()/10;
*timestamp= my_time();
but it avoids calling OS time functions twice, if possible.
*/
void my_diff_and_hrtime(my_timediff_t *interval, my_hrtime_t *timestamp)
{
interval->val= my_getsystime() / 10;
#if defined(__WIN__) || defined(HAVE_GETHRTIME)
*timestamp= my_hrtime();
#else
timestamp->val= interval->val;
#endif
}
void my_time_init()
{
#ifdef __WIN__
FILETIME ft;
LARGE_INTEGER li, t_cnt;
DBUG_ASSERT(sizeof(LARGE_INTEGER) == sizeof(query_performance_frequency));
if (QueryPerformanceFrequency((LARGE_INTEGER *)&query_performance_frequency) == 0)
query_performance_frequency= 0;
else
{
GetSystemTimeAsFileTime(&ft);
li.LowPart= ft.dwLowDateTime;
li.HighPart= ft.dwHighDateTime;
query_performance_offset= li.QuadPart-OFFSET_TO_EPOC;
QueryPerformanceCounter(&t_cnt);
query_performance_offset-= (t_cnt.QuadPart /
query_performance_frequency * 10000000 +
t_cnt.QuadPart %
query_performance_frequency * 10000000 /
query_performance_frequency);
}
#elif defined(HAVE_GETHRTIME)
gethrtime_offset= gethrtime();
#endif
}
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