2 * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
3 * The Regents of the University of California. All rights reserved.
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6 * modification, are permitted provided that: (1) source code distributions
7 * retain the above copyright notice and this paragraph in its entirety, (2)
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10 * provided with the distribution, and (3) all advertising materials mentioning
11 * features or use of this software display the following acknowledgement:
12 * ``This product includes software developed by the University of California,
13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
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15 * or promote products derived from this software without specific prior
17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
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31 #define JAN_1970 INT64_T_CONSTANT(2208988800) /* 1970 - 1900 in seconds */
34 p_ntp_time(netdissect_options *ndo,
35 const struct l_fixedpt *lfp)
42 i = GET_BE_U_4(lfp->int_part);
43 uf = GET_BE_U_4(lfp->fraction);
45 if (ff < 0.0) /* some compilers are buggy */
47 ff = ff / FMAXINT; /* shift radix point by 32 bits */
48 f = (uint32_t)(ff * 1000000000.0); /* treat fraction as parts per billion */
49 ND_PRINT("%u.%09u", i, f);
53 * print the UTC time in human-readable format.
56 int64_t seconds_64bit = (int64_t)i - JAN_1970;
61 seconds = (time_t)seconds_64bit;
62 if (seconds != seconds_64bit) {
64 * It doesn't fit into a time_t, so we can't hand it
67 ND_PRINT(" (unrepresentable)");
69 tm = gmtime(&seconds);
72 * gmtime() can't handle it.
73 * (Yes, that might happen with some version of
74 * Microsoft's C library.)
76 ND_PRINT(" (unrepresentable)");
78 /* use ISO 8601 (RFC3339) format */
79 strftime(time_buf, sizeof (time_buf), "%Y-%m-%dT%H:%M:%SZ", tm);
80 ND_PRINT(" (%s)", time_buf);