Function get_current_time

Engine/source/core/util/uuid.cpp:240–270

get-current_time -- get time as 60 bit 100ns ticks since whenever. Compensate for the fact that real clock resolution is less than 100ns. */

/* get-current_time -- get time as 60 bit 100ns ticks since whenever.
   Compensate for the fact that real clock resolution is less than 100ns. */
static void get_current_time(uuid_time_t * timestamp)
{
    uuid_time_t         time_now;
    static uuid_time_t  time_last;
    static unsigned16   uuids_this_tick;
    static int          inited = 0;
    
    if (!inited) {
        get_system_time(&time_now);
        uuids_this_tick = UUIDS_PER_TICK;
        inited = 1;
    };
	
    while (1) {
	get_system_time(&time_now);
        
	/* if clock reading changed since last UUID generated... */
	if (time_last != time_now) {
	    /* reset count of uuids gen'd with this clock reading */
	    uuids_this_tick = 0;
	    break;
	};
	if (uuids_this_tick < UUIDS_PER_TICK) {
	    uuids_this_tick++;
	    break;
	};        /* going too fast for our clock; spin */
    };    /* add the count of uuids to low order bits of the clock reading */

    *timestamp = time_now + uuids_this_tick;
    time_last = time_now;
}

/* true_random -- generate a crypto-quality random number.
   This sample doesn't do that. */