need to declare errno

[unix-history] / usr / src / bin / date / date.c

#ifndef lint
static char sccsid[] = "@(#)date.c      4.8 (Berkeley) %G%";
#endif not lint

/*
* Date - print and set date
* Modified by Riccardo Gusella to work with timed 
*/

#include <sys/types.h>
#include <stdio.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#define TSPTYPES
#include <protocols/timed.h>
#include <sys/file.h>
#include <errno.h>
#include <syslog.h>
#include <utmp.h>

#define WTMP "/usr/adm/wtmp"

struct  timeval tv, now;
struct  timezone tz;
char    *ap, *ep, *sp;
int     uflag;

char    *timezone();
static  int     dmsize[12] =
   { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
static char *usage = "usage: date [-u] [yymmddhhmm[.ss]]\n";

struct utmp wtmp[2] = {
       { "|", "", "", 0 },
       { "{", "", "", 0 }
};

char    *ctime();
char    *asctime();
struct  tm *localtime();
struct  tm *gmtime();

char *strcpy();
char *username, *getlogin();

#define WAITACK         10      /* seconds */
#define WAITDATEACK     5       /* seconds */

int sock, length, port;
int ready, found;
char hostname[32];
struct timeval tout;
struct servent *srvp;
struct hostent *hp, *gethostbyname();
struct tsp msg;
struct sockaddr_in sin, dest, from;

main(argc, argv)
       int argc;
       char *argv[];
{
       int wf;
       int timed_ack;
       register char *tzn;
       extern int errno;
       int bytenetorder(), bytehostorder();

       (void) gettimeofday(&tv, &tz);

       if (argc > 1 && strcmp(argv[1], "-u") == 0) {
               argc--;
               argv++;
               uflag++;
       }
       if (argc > 2) {
               printf(usage);
               exit(1);
       }
       if (argc == 1) 
               goto display;

       if (getuid() != 0) {
               printf("You are not superuser: date not set\n");
               exit(1);
       }
       username = getlogin();
       if (username == NULL) {
               printf("Cannot record your name: date not set\n");
               exit(1);
       }
       syslog(LOG_ERR, "date: set by %s", username);

       ap = argv[1];
       wtmp[0].ut_time = tv.tv_sec;
       if (gtime()) {
               printf(usage);
               exit(1);
       }
       /* convert to GMT assuming local time */
       if (uflag == 0) {
               tv.tv_sec += (long)tz.tz_minuteswest*60;
               /* now fix up local daylight time */
               if (localtime((long *)&tv.tv_sec)->tm_isdst)
                       tv.tv_sec -= 60*60;
       }
       (void) open("/etc/timed", O_WRONLY, 01700);
       if (errno != ETXTBSY) {
               if (settimeofday(&tv, (struct timezone *)0) < 0) {
                       perror("settimeofday");
                       exit(1);
               }
               if ((wf = open(WTMP, 1)) >= 0) {
                       (void) time((long *)&wtmp[1].ut_time);
                       (void) lseek(wf, (off_t)0L, 2);
                       (void) write(wf, (char *)wtmp, sizeof(wtmp));
                       (void) close(wf);
               }
               goto display;
       }

/*
* Here we set the date in the machines controlled by timedaemons
* by communicating the new date to the local timedaemon. 
* If the timedaemon is in the master state, it performs the correction on 
* all slaves. If it is in the slave state, it notifies the master 
* that a correction is needed.
*/

       srvp = getservbyname("timed", "udp");
       if (srvp == 0) {
               fprintf(stderr, "udp/timed: unknown service\n");
               exit(1);
       }       
       dest.sin_port = srvp->s_port;
       dest.sin_family = AF_INET;
       sock = socket(AF_INET, SOCK_DGRAM, 0);
       if (sock < 0) {
               perror("opening socket");
               exit(1);
       }

       sin.sin_family = AF_INET;
       for (port = IPPORT_RESERVED - 1; port > IPPORT_RESERVED / 2; port--) {
               sin.sin_port = htons((u_short)port);
               if (bind(sock, (struct sockaddr *)&sin, sizeof (sin)) >= 0)
                       break;
               if (errno != EADDRINUSE && errno != EADDRNOTAVAIL) {
                       perror("bind");
                       (void) close(sock);
                       exit(1);
               }
       }
       if (port == IPPORT_RESERVED / 2) {
               fprintf(stderr, "socket: All ports in use\n");
               (void) close(sock);
               exit(1);
       }

       (void) gethostname(hostname,sizeof(hostname));
       hp = gethostbyname(hostname);
       if (hp == NULL) {
               perror("gethostbyname");
               exit(1);
       }
       bcopy(hp->h_addr, &dest.sin_addr.s_addr, hp->h_length);

       msg.tsp_type = TSP_DATE;
       (void) strcpy(msg.tsp_name, hostname);
       (void) gettimeofday(&now, (struct timezone *)0);
       timevalsub(&tv, &now);
       msg.tsp_time = tv;
       bytenetorder(&msg);
       length = sizeof(struct sockaddr_in);
       if (sendto(sock, (char *)&msg, sizeof(struct tsp), 0, 
                                               &dest, length) < 0) {
               perror("sendto");
               exit(1);
       }

       timed_ack = -1;
       tout.tv_sec = WAITACK;
       tout.tv_usec = 0;
loop:
       ready = 1<<sock;
       found = select(20, &ready, (int *)0, (int *)0, &tout);
       if (found) {
               length = sizeof(struct sockaddr_in);
               if (recvfrom(sock, (char *)&msg, sizeof(struct tsp), 0, 
                                                       &from, &length) < 0) {
                       perror("recvfrom");
                       exit(1);
               }
               bytehostorder(&msg);

               switch (msg.tsp_type) {

               case TSP_ACK:
                       timed_ack = TSP_ACK;
                       tout.tv_sec = WAITDATEACK;
                       tout.tv_usec = 0;
                       goto loop;
                       break;
               case TSP_DATEACK:
                       goto display;
                       break;
               default:
                       printf("Wrong ack received: %s\n", 
                                               tsptype[msg.tsp_type]);
                       timed_ack = -1;
                       break;
               }
       }

       if (timed_ack == TSP_ACK) {
               printf("Network date being set\n");
               exit(0);
       } else {
               printf("Communication problems\n");
               exit(1);
       }

display:
       (void) gettimeofday(&tv, (struct timezone *)0);
       if (uflag) {
               ap = asctime(gmtime((long *)&tv.tv_sec));
               tzn = "GMT";
       } else {
               struct tm *tp;
               tp = localtime((long *)&tv.tv_sec);
               ap = asctime(tp);
               tzn = timezone(tz.tz_minuteswest, tp->tm_isdst);
       }
       printf("%.20s", ap);
       if (tzn)
               printf("%s", tzn);
       printf("%s", ap+19);
}

gtime()
{
       register int i, year, month;
       int day, hour, mins, secs;
       struct tm *L;
       char x;

       ep = ap;
       while(*ep) ep++;
       sp = ap;
       while(sp < ep) {
               x = *sp;
               *sp++ = *--ep;
               *ep = x;
       }
       sp = ap;
       (void) gettimeofday(&tv, (struct timezone *)0);
       L = localtime((long *)&tv.tv_sec);
       secs = gp(-1);
       if (*sp != '.') {
               mins = secs;
               secs = 0;
       } else {
               sp++;
               mins = gp(-1);
       }
       hour = gp(-1);
       day = gp(L->tm_mday);
       month = gp(L->tm_mon+1);
       year = gp(L->tm_year);
       if (*sp)
               return (1);
       if (month < 1 || month > 12 ||
           day < 1 || day > 31 ||
           mins < 0 || mins > 59 ||
           secs < 0 || secs > 59)
               return (1);
       if (hour == 24) {
               hour = 0;
               day++;
       }
       if (hour < 0 || hour > 23)
               return (1);
       tv.tv_sec = 0;
       year += 1900;
       for (i = 1970; i < year; i++)
               tv.tv_sec += dysize(i);
       /* Leap year */
       if (dysize(year) == 366 && month >= 3)
               tv.tv_sec++;
       while (--month)
               tv.tv_sec += dmsize[month-1];
       tv.tv_sec += day-1;
       tv.tv_sec = 24*tv.tv_sec + hour;
       tv.tv_sec = 60*tv.tv_sec + mins;
       tv.tv_sec = 60*tv.tv_sec + secs;
       return (0);
}

gp(dfault)
{
       register int c, d;

       if (*sp == 0)
               return (dfault);
       c = (*sp++) - '0';
       d = (*sp ? (*sp++) - '0' : 0);
       if (c < 0 || c > 9 || d < 0 || d > 9)
               return (-1);
       return (c+10*d);
}

timevalsub(t1, t2)
struct timeval *t1, *t2;
{
       t1->tv_sec -= t2->tv_sec;
       t1->tv_usec -= t2->tv_usec;
       if (t1->tv_usec < 0) {
               t1->tv_sec--;
               t1->tv_usec += 1000000;
       }
       if (t1->tv_usec >= 1000000) {
               t1->tv_sec++;
               t1->tv_usec -= 1000000;
       }
}

bytenetorder(ptr)
struct tsp *ptr;
{
       ptr->tsp_seq = htons((u_short)ptr->tsp_seq);
       ptr->tsp_time.tv_sec = htonl((u_long)ptr->tsp_time.tv_sec);
       ptr->tsp_time.tv_usec = htonl((u_long)ptr->tsp_time.tv_usec);
}

bytehostorder(ptr)
struct tsp *ptr;
{
       ptr->tsp_seq = ntohs((u_short)ptr->tsp_seq);
       ptr->tsp_time.tv_sec = ntohl((u_long)ptr->tsp_time.tv_sec);
       ptr->tsp_time.tv_usec = ntohl((u_long)ptr->tsp_time.tv_usec);
}