minix3/lib/libc/sys/adjtime.c

39 lines
974 B
C

#include <sys/cdefs.h>
#include <lib.h>
#include "namespace.h"
#include <string.h>
#include <sys/time.h>
#include <time.h>
#ifdef __weak_alias
__weak_alias(adjtime, __adjtime50);
#endif
int adjtime(const struct timeval *delta, struct timeval *olddelta)
{
message m;
memset(&m, 0, sizeof(m));
m.m_lc_pm_time.clk_id = CLOCK_REALTIME;
m.m_lc_pm_time.now = 0; /* use adjtime() method to slowly adjust the clock. */
m.m_lc_pm_time.sec = delta->tv_sec;
m.m_lc_pm_time.nsec = delta->tv_usec * 1000; /* convert usec to nsec */
if (_syscall(PM_PROC_NR, PM_CLOCK_SETTIME, &m) < 0)
return -1;
if (olddelta != NULL) {
/* the kernel returns immediately and the adjustment happens in the
* background. Also, any currently running adjustment is stopped by
* another call to adjtime(2), so the only values possible on Minix
* for olddelta are those of delta.
*/
olddelta->tv_sec = delta->tv_sec;
olddelta->tv_usec = delta->tv_usec;
}
return 0;
}