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Diffstat (limited to 'i/pc104/initrd/conf/busybox/util-linux/rdate.c')
-rw-r--r--i/pc104/initrd/conf/busybox/util-linux/rdate.c71
1 files changed, 71 insertions, 0 deletions
diff --git a/i/pc104/initrd/conf/busybox/util-linux/rdate.c b/i/pc104/initrd/conf/busybox/util-linux/rdate.c
new file mode 100644
index 0000000..33cf64e
--- /dev/null
+++ b/i/pc104/initrd/conf/busybox/util-linux/rdate.c
@@ -0,0 +1,71 @@
+/* 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>
+ *
+ * Licensed under GPL v2 or later, see file License for details.
+*/
+
+#include "busybox.h"
+
+enum { RFC_868_BIAS = 2208988800UL };
+
+static void socket_timeout(int sig)
+{
+ bb_error_msg_and_die("timeout connecting to time server");
+}
+
+static time_t askremotedate(const char *host)
+{
+ uint32_t nett;
+ int fd;
+
+ /* Add a timeout for dead or inaccessible servers */
+ alarm(10);
+ signal(SIGALRM, socket_timeout);
+
+ fd = create_and_connect_stream_or_die(host, bb_lookup_port("time", "tcp", 37));
+
+ if (safe_read(fd, (void *)&nett, 4) != 4) /* read time from server */
+ bb_error_msg_and_die("%s did not send the complete time", 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
+ */
+
+ return ntohl(nett) - RFC_868_BIAS;
+}
+
+int rdate_main(int argc, char **argv);
+int rdate_main(int argc, char **argv)
+{
+ time_t remote_time;
+ unsigned long flags;
+
+ opt_complementary = "-1";
+ flags = getopt32(argc, argv, "sp");
+
+ remote_time = askremotedate(argv[optind]);
+
+ if ((flags & 2) == 0) {
+ time_t current_time;
+
+ time(&current_time);
+ if (current_time == remote_time)
+ bb_error_msg("current time matches remote time");
+ else
+ if (stime(&remote_time) < 0)
+ bb_perror_msg_and_die("cannot set time of day");
+ }
+
+ if ((flags & 1) == 0)
+ printf("%s", ctime(&remote_time));
+
+ return EXIT_SUCCESS;
+}