Re: droped out precise time calculations in src/interfaces/libpq/fe-connect.c

Denis A Ustimenko wrote:
> On Sun, Oct 13, 2002 at 09:02:55PM -0700, Joe Conway wrote:
> > Denis A Ustimenko wrote:
> > >>Bruce, why have all precise time calculations been droped out in 1.206?
> > >>If there is no
> > >>gettimeofday in win32?
> >
> > gettimeofday was not portable to win32 (at least not that I could find) and
> > hence broke the win32 build of the clients.
> >
>
> GetSystemTimeAsFileTime should help.
>
> http://msdn.microsoft.com/library/default.asp?url=/library/en-us/sysinfo/base/getsystemtimeasfiletime.asp

It's not clear to me how we could get this into something we can deal
with like gettimeofday.

I looked at the Apache APR project, and they have a routine that returns
the microseconds since 1970 for Unix:

/* NB NB NB NB This returns GMT!!!!!!!!!! */
APR_DECLARE(apr_time_t) apr_time_now(void)
{
struct timeval tv;
gettimeofday(&tv, NULL);
return tv.tv_sec * APR_USEC_PER_SEC + tv.tv_usec;
}

and for Win32:

APR_DECLARE(apr_time_t) apr_time_now(void)
{
LONGLONG aprtime = 0;
FILETIME time;
#ifndef _WIN32_WCE
GetSystemTimeAsFileTime(&time);
#else
SYSTEMTIME st;
GetSystemTime(&st);
SystemTimeToFileTime(&st, &time);
#endif
FileTimeToAprTime(&aprtime, &time);
return aprtime;
}

and FileTimeToAprTime() is:

/* Number of micro-seconds between the beginning of the Windows epoch
* (Jan. 1, 1601) and the Unix epoch (Jan. 1, 1970)
*/
#define APR_DELTA_EPOCH_IN_USEC APR_TIME_C(11644473600000000);


__inline void FileTimeToAprTime(apr_time_t *result, FILETIME *input)
{
/* Convert FILETIME one 64 bit number so we can work with it. */
*result = input->dwHighDateTime;
*result = (*result) << 32;
*result |= input->dwLowDateTime;
*result /= 10; /* Convert from 100 nano-sec periods to micro-seconds. */
*result -= APR_DELTA_EPOCH_IN_USEC; /* Convert from Windows epoch to Unix epoch */
return;
}

So, this is what needs to be dealt with to get it working.

--
Bruce Momjian | http://candle.pha.pa.us
pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073