cleanup low-level time handling

2004-08-15 22:41:46 +00:00
parent 3776d4a13f
commit 445d8a6cf2
1 changed files with 1 additions and 51 deletions
@@ -11,60 +11,10 @@ const RageTimer RageZeroTimer(0,0);
 static void GetTime( unsigned &secs, unsigned &us )
 {
-	/*
+	uint64_t usecs = ArchHooks::GetMicrosecondsSinceStart( true );
 	 * Ticks may be less than last for at least two reasons.  The underlying timer may
 	 * be 32-bit and use millisecs internally, or the system clock may have moved backwards.
 	 * If the system clock moves backwards, we can't just clamp the time; if it moved back
 	 * an hour, we'll sit around for an hour until it catches up.
 	 *
 	 * Keep track of an offset: the amount of time to add to the result of GetMicrosecondsSinceStart.
 	 * If we move back by 100ms, the offset will be increased by 100ms.  If we loop, the
 	 * offset will be increased by the duration 2^32 ticks.  This is stored in the same
 	 * notation as RageTimer: one 32-bit int for seconds and another for microseconds, so
 	 * wrapping isn't a problem.
 	 */
 	static uint64_t last = 0;
 	static uint32_t offset_secs = 0, offset_us = 0;
 	const uint64_t usecs = ArchHooks::GetMicrosecondsSinceStart( true );
 	/* The time has wrapped if the last time was very high and the current time is very low. */
 	const uint64_t one_day = uint64_t(24*60*60)*1000000;
 	if( last > (0-one_day) && usecs < one_day )
 	{
 		const uint32_t wraparound_secs = 4294967; /* (2^32 / 1000) */
 		const uint32_t wraparound_us = 296000;    /* (2^32 % 1000) * 1000 */
 		offset_secs += wraparound_secs;
 		offset_us += wraparound_us;
 	}
 	else if( usecs < last )
 	{
 		/* The time has moved backwards.  Increase the offset by the amount we moved. */
 		const uint64_t offset_us_diff = last - usecs;
 		offset_secs += unsigned(offset_us_diff/1000000);
 		offset_us   += unsigned(offset_us_diff%1000000);
 	}
 	if( offset_us >= TIMESTAMP_RESOLUTION )
 	{
 		offset_us -= TIMESTAMP_RESOLUTION;
 		++offset_secs;
 	}
 	last = usecs;
 	secs = unsigned(usecs / 1000000);
 	us =   unsigned(usecs % 1000000);
 	secs += offset_secs;
 	us += offset_us;
 	if( us >= TIMESTAMP_RESOLUTION )
 	{
 		us -= TIMESTAMP_RESOLUTION;
 		++secs;
 	}
 }
 float RageTimer::GetTimeSinceStart()