gettimeofday.c File Reference

#include "c.h"
#include <sys/time.h>

Include dependency graph for gettimeofday.c:

Go to the source code of this file.

Macros
#define	FILETIME_UNITS_PER_SEC   10000000L
#define	FILETIME_UNITS_PER_USEC   10

Typedefs
typedef VOID(WINAPI *	PgGetSystemTimeFn) (LPFILETIME)

Functions
static void WINAPI	init_gettimeofday (LPFILETIME lpSystemTimeAsFileTime)
int	gettimeofday (struct timeval *tp, struct timezone *tzp)

Variables
static const unsigned __int64	epoch = UINT64CONST(116444736000000000)
static PgGetSystemTimeFn	pg_get_system_time = &init_gettimeofday

Macro Definition Documentation

FILETIME_UNITS_PER_SEC

#define FILETIME_UNITS_PER_SEC   10000000L

Definition at line 40 of file gettimeofday.c.

Referenced by gettimeofday().

FILETIME_UNITS_PER_USEC

#define FILETIME_UNITS_PER_USEC   10

Definition at line 41 of file gettimeofday.c.

Referenced by gettimeofday().

Typedef Documentation

PgGetSystemTimeFn

typedef VOID(WINAPI * PgGetSystemTimeFn) (LPFILETIME)

Definition at line 48 of file gettimeofday.c.

Function Documentation

gettimeofday()

int gettimeofday	(	struct timeval *	tp,
		struct timezone *	tzp
	)

Definition at line 104 of file gettimeofday.c.

References epoch, FILETIME_UNITS_PER_SEC, and FILETIME_UNITS_PER_USEC.

Referenced by BootStrapXLOG(), feGetCurrentTimestamp(), GetCurrentTimestamp(), GuessControlValues(), IsCheckpointOnSchedule(), log_line_prefix(), PerformRadiusTransaction(), pg_rusage_init(), pqTraceFormatTimestamp(), ResetUsage(), setup_formatted_log_time(), ShowUsage(), timeofday(), and try_complete_step().

{
    FILETIME    file_time;
    ULARGE_INTEGER ularge;

    (*pg_get_system_time) (&file_time);
    ularge.LowPart = file_time.dwLowDateTime;
    ularge.HighPart = file_time.dwHighDateTime;

    tp->tv_sec = (long) ((ularge.QuadPart - epoch) / FILETIME_UNITS_PER_SEC);
    tp->tv_usec = (long) (((ularge.QuadPart - epoch) % FILETIME_UNITS_PER_SEC)
                          / FILETIME_UNITS_PER_USEC);

    return 0;
}

init_gettimeofday()

static void WINAPI init_gettimeofday ( LPFILETIME  lpSystemTimeAsFileTime )

static

Definition at line 62 of file gettimeofday.c.

References pg_get_system_time.

{
    /*
     * Because it's guaranteed that kernel32.dll will be linked into our
     * address space already, we don't need to LoadLibrary it and worry about
     * closing it afterwards, so we're not using Pg's dlopen/dlsym() wrapper.
     *
     * We'll just look up the address of GetSystemTimePreciseAsFileTime if
     * present.
     *
     * While we could look up the Windows version and skip this on Windows
     * versions below Windows 8 / Windows Server 2012 there isn't much point,
     * and determining the windows version is its self somewhat Windows
     * version and development SDK specific...
     */
    pg_get_system_time = (PgGetSystemTimeFn) GetProcAddress(GetModuleHandle(TEXT("kernel32.dll")),
                                                            "GetSystemTimePreciseAsFileTime");
    if (pg_get_system_time == NULL)
    {
        /*
         * The expected error from GetLastError() is ERROR_PROC_NOT_FOUND, if
         * the function isn't present. No other error should occur.
         *
         * We can't report an error here because this might be running in
         * frontend code; and even if we're in the backend, it's too early to
         * elog(...) if we get some unexpected error.  Also, it's not a
         * serious problem, so just silently fall back to
         * GetSystemTimeAsFileTime irrespective of why the failure occurred.
         */
        pg_get_system_time = &GetSystemTimeAsFileTime;
    }

    (*pg_get_system_time) (lpSystemTimeAsFileTime);
}

Variable Documentation

epoch

const unsigned __int64 epoch = UINT64CONST(116444736000000000)

static

Definition at line 34 of file gettimeofday.c.

Referenced by AdvanceNextFullTransactionIdPastXid(), FullTransactionIdFromXidAndCtx(), GetEpochTime(), gettimeofday(), timestamp_part_common(), timestamptz_part_common(), widen_snapshot_xid(), and XLogRecGetFullXid().

pg_get_system_time

PgGetSystemTimeFn pg_get_system_time = &init_gettimeofday

static

Definition at line 54 of file gettimeofday.c.

Referenced by init_gettimeofday().