Contents of /tags/mkinitrd-6_1_4/busybox/util-linux/rdate.c
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Wed Aug 5 16:25:39 2009 UTC (15 years, 1 month ago) by niro
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File size: 1752 byte(s)
Wed Aug 5 16:25:39 2009 UTC (15 years, 1 month ago) by niro
File MIME type: text/plain
File size: 1752 byte(s)
tagged 'mkinitrd-6_1_4'
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * The Rdate command will ask a time server for the RFC 868 time |
4 | * and optionally set the system time. |
5 | * |
6 | * by Sterling Huxley <sterling@europa.com> |
7 | * |
8 | * Licensed under GPL v2 or later, see file License for details. |
9 | */ |
10 | |
11 | #include "libbb.h" |
12 | |
13 | enum { RFC_868_BIAS = 2208988800UL }; |
14 | |
15 | static void socket_timeout(int sig UNUSED_PARAM) |
16 | { |
17 | bb_error_msg_and_die("timeout connecting to time server"); |
18 | } |
19 | |
20 | static time_t askremotedate(const char *host) |
21 | { |
22 | uint32_t nett; |
23 | int fd; |
24 | |
25 | /* Add a timeout for dead or inaccessible servers */ |
26 | alarm(10); |
27 | signal(SIGALRM, socket_timeout); |
28 | |
29 | fd = create_and_connect_stream_or_die(host, bb_lookup_port("time", "tcp", 37)); |
30 | |
31 | if (safe_read(fd, (void *)&nett, 4) != 4) /* read time from server */ |
32 | bb_error_msg_and_die("%s did not send the complete time", host); |
33 | close(fd); |
34 | |
35 | /* convert from network byte order to local byte order. |
36 | * RFC 868 time is the number of seconds |
37 | * since 00:00 (midnight) 1 January 1900 GMT |
38 | * the RFC 868 time 2,208,988,800 corresponds to 00:00 1 Jan 1970 GMT |
39 | * Subtract the RFC 868 time to get Linux epoch |
40 | */ |
41 | |
42 | return ntohl(nett) - RFC_868_BIAS; |
43 | } |
44 | |
45 | int rdate_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
46 | int rdate_main(int argc UNUSED_PARAM, char **argv) |
47 | { |
48 | time_t remote_time; |
49 | unsigned long flags; |
50 | |
51 | opt_complementary = "-1"; |
52 | flags = getopt32(argv, "sp"); |
53 | |
54 | remote_time = askremotedate(argv[optind]); |
55 | |
56 | if ((flags & 2) == 0) { |
57 | time_t current_time; |
58 | |
59 | time(¤t_time); |
60 | if (current_time == remote_time) |
61 | bb_error_msg("current time matches remote time"); |
62 | else |
63 | if (stime(&remote_time) < 0) |
64 | bb_perror_msg_and_die("cannot set time of day"); |
65 | } |
66 | |
67 | if ((flags & 1) == 0) |
68 | printf("%s", ctime(&remote_time)); |
69 | |
70 | return EXIT_SUCCESS; |
71 | } |