Files
seta75D 2e8a93c394 Init
2021-10-11 18:20:23 -03:00

110 lines
2.2 KiB
C

#if !defined(lint) && defined(SCCSIDS)
static char sccsid[] = "@(#)rtime.c 1.1 92/07/30 Copyr 1987 Sun Micro";
#endif
/*
* rtime - get time from remote machine
*
* Copyright (C) 1986, Sun Microsystems, Inc.
*
* gets time, obtaining value from host
* on the udp/time socket. Since timeserver returns
* with time of day in seconds since Jan 1, 1900, must
* subtract seconds before Jan 1, 1970 to get
* what unix uses.
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <sys/errno.h>
#include <netinet/in.h>
#include <stdio.h>
#define NYEARS (1970 - 1900)
#define TOFFSET (60*60*24*(365*NYEARS + (NYEARS/4)))
extern errno;
static void do_close();
rtime(addrp, timep, timeout)
struct sockaddr_in *addrp;
struct timeval *timep;
struct timeval *timeout;
{
int s;
fd_set readfds;
int res;
unsigned long thetime;
struct sockaddr_in from;
int fromlen;
int type;
if (timeout == NULL) {
type = SOCK_STREAM;
} else {
type = SOCK_DGRAM;
}
s = socket(AF_INET, type, 0);
if (s < 0) {
return (-1);
}
addrp->sin_family = AF_INET;
addrp->sin_port = htons(IPPORT_TIMESERVER);
if (type == SOCK_DGRAM) {
res = sendto(s, (char *)&thetime, sizeof (thetime), 0,
(struct sockaddr *)addrp, sizeof (*addrp));
if (res < 0) {
do_close(s);
return (-1);
}
do {
FD_ZERO(&readfds);
FD_SET(s, &readfds);
res = select(_rpc_dtablesize(), &readfds, (int *)NULL,
(int *)NULL, timeout);
} while (res < 0 && errno == EINTR);
if (res <= 0) {
if (res == 0) {
errno = ETIMEDOUT;
}
do_close(s);
return (-1);
}
fromlen = sizeof (from);
res = recvfrom(s, (char *)&thetime, sizeof (thetime), 0,
(struct sockaddr *)&from, &fromlen);
do_close(s);
if (res < 0) {
return (-1);
}
} else {
if (connect(s, (struct sockaddr *)addrp, sizeof (*addrp)) < 0) {
do_close(s);
return (-1);
}
res = read(s, (char *)&thetime, sizeof (thetime));
do_close(s);
if (res < 0) {
return (-1);
}
}
if (res != sizeof (thetime)) {
errno = EIO;
return (-1);
}
thetime = ntohl(thetime);
timep->tv_sec = thetime - TOFFSET;
timep->tv_usec = 0;
return (0);
}
static void
do_close(s)
int s;
{
int save;
save = errno;
(void) close(s);
errno = save;
}