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authorEric Andersen2000-08-21 23:04:00 +0000
committerEric Andersen2000-08-21 23:04:00 +0000
commit6ab22027d09a4038a89dd3d6d003a66a5490b818 (patch)
tree1d882f65e0dcc9b1efb0bb825ae9bf1a86ffc3e2 /rdate.c
parentfba9c00071eff20f65b8ff6b1e5fa7e5933e038d (diff)
downloadbusybox-6ab22027d09a4038a89dd3d6d003a66a5490b818.zip
busybox-6ab22027d09a4038a89dd3d6d003a66a5490b818.tar.gz
Oops. Forgot to commit rdate.c.
-Erik
Diffstat (limited to 'rdate.c')
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1 files changed, 135 insertions, 0 deletions
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+/* vi: set sw=4 ts=4: */
+/*
+ * The Rdate command will ask a time server for the RFC 868 time
+ * and optionally set the system time.
+ *
+ * by Sterling Huxley <sterling@europa.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+*/
+
+#include "internal.h"
+#define BB_DECLARE_EXTERN
+#include "messages.c"
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <getopt.h>
+
+
+#define RFC_868_BIAS 2208988800UL
+
+int setdate= 0;
+int printdate= 0;
+
+time_t askremotedate(char *host)
+{
+ struct hostent *h;
+ struct sockaddr_in sin;
+ struct servent *tserv;
+ unsigned long int nett, localt;
+ int fd;
+
+ if (!(h = gethostbyname(host))) { /* get the IP addr */
+ errorMsg("%s: %s\n", host, strerror(errno));
+ return(-1);
+ }
+ if ((tserv = getservbyname("time", "tcp")) == NULL) { /* find port # */
+ errorMsg("%s: %s\n", "time", strerror(errno));
+ return(-1);
+ }
+ if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) { /* get net connection */
+ errorMsg("%s: %s\n", "socket", strerror(errno));
+ return(-1);
+ }
+
+ memcpy(&sin.sin_addr, h->h_addr, sizeof(sin.sin_addr));
+ sin.sin_port= tserv->s_port;
+ sin.sin_family = AF_INET;
+
+ if (connect(fd, &sin, sizeof(sin)) < 0) { /* connect to time server */
+ errorMsg("%s: %s\n", host, strerror(errno));
+ close(fd);
+ return(-1);
+ }
+ if (read(fd, &nett, 4) != 4) { /* read time from server */
+ close(fd);
+ errorMsg("%s did not send the complete time\n", host);
+ }
+ close(fd);
+
+ /* convert from network byte order to local byte order.
+ * RFC 868 time is the number of seconds
+ * since 00:00 (midnight) 1 January 1900 GMT
+ * the RFC 868 time 2,208,988,800 corresponds to 00:00 1 Jan 1970 GMT
+ * Subtract the RFC 868 time to get Linux epoch
+ */
+ localt= ntohl(nett) - RFC_868_BIAS;
+
+ return(localt);
+}
+
+int rdate_main(int argc, char **argv)
+{
+ time_t time;
+ int opt;
+
+ /* Interpret command line args */
+ /* do special-case option parsing */
+ if (argv[1] && (strcmp(argv[1], "--help") == 0))
+ usage(rdate_usage);
+
+ /* do normal option parsing */
+ while ((opt = getopt(argc, argv, "Hsp")) > 0) {
+ switch (opt) {
+ default:
+ case 'H':
+ usage(rdate_usage);
+ return(FALSE);
+ break;
+ case 's':
+ setdate++;
+ break;
+ case 'p':
+ printdate++;
+ break;
+ }
+ }
+
+ /* the default action is to set the date */
+ if (printdate==0 && setdate==0) setdate++;
+
+ if (optind == argc) {
+ usage(rdate_usage);
+ return(FALSE);
+ }
+
+ if ((time= askremotedate(argv[optind])) == (time_t)-1) {
+ return(FALSE);
+ }
+ if (setdate) {
+ if (stime(&time) < 0)
+ fatalError("Could not set time of day: %s\n", strerror(errno));
+ }
+ if (printdate) {
+ fprintf(stdout, "%s", ctime(&time));
+ }
+
+ return(TRUE);
+}