db/os/os_sleep.c

	os_sleep.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1997, 1998
 *  Sleepycat Software.  All rights reserved.
 */

#include "config.h"

#ifndef lint
static const char sccsid[] = "@(#)os_sleep.c    10.12 (Sleepycat) 10/12/98";
#endif /* not lint */

#ifndef NO_SYSTEM_INCLUDES
#include <sys/types.h>
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif

#include <errno.h>
#ifndef HAVE_SYS_TIME_H
#include <time.h>
#endif
#include <unistd.h>
#endif

#include "db_int.h"
#include "os_jump.h"

/*
 * __os_sleep --
 *  Yield the processor for a period of time.
 *
 * PUBLIC: int __os_sleep __P((u_long, u_long));
 */
int
__os_sleep(secs, usecs)
    u_long secs, usecs;     /* Seconds and microseconds. */
{
    struct timeval t;

    /* Don't require that the values be normalized. */
    for (; usecs >= 1000000; ++secs, usecs -= 1000000)
        ;

    if (__db_jump.j_sleep != NULL)
        return (__db_jump.j_sleep(secs, usecs));

    /*
     * It's important that we yield the processor here so that other
     * processes or threads are permitted to run.
     */
    t.tv_sec = secs;
    t.tv_usec = usecs;
    return (select(0, NULL, NULL, NULL, &t) == -1 ? errno : 0);
}