1 /* 2 * caltontp - convert a date to an NTP time 3 */ 4 #include <config.h> 5 #include <sys/types.h> 6 7 #include "ntp_types.h" 8 #include "ntp_calendar.h" 9 #include "ntp_stdlib.h" 10 #include "ntp_assert.h" 11 #include "ntp_unixtime.h" 12 13 /* 14 * Juergen Perlinger, 2008-11-12 15 * Add support for full calendar calculatios. If the day-of-year is provided 16 * (that is, not zero) it will be used instead of month and day-of-month; 17 * otherwise a full turn through the calendar calculations will be taken. 18 * 19 * I know that Harlan Stenn likes to see assertions in production code, and I 20 * agree there, but it would be a tricky thing here. The algorithm is quite 21 * capable of producing sensible answers even to seemingly weird inputs: the 22 * date <any year here>-03-00, the 0.th March of the year, will be automtically 23 * treated as the last day of February, no matter whether the year is a leap 24 * year or not. So adding constraints is merely for the benefit of the callers, 25 * because the only thing we can check for consistency is our input, produced 26 * by somebody else. 27 * 28 * BTW: A total roundtrip using 'caljulian' would be a quite shaky thing: 29 * Because of the truncation of the NTP time stamp to 32 bits and the epoch 30 * unfolding around the current time done by 'caljulian' the roundtrip does 31 * *not* necessarily reproduce the input, especially if the time spec is more 32 * than 68 years off from the current time... 33 */ 34 35 uint32_t 36 caltontp( 37 const struct calendar *jt 38 ) 39 { 40 int32_t eraday; /* CE Rata Die number */ 41 vint64 ntptime;/* resulting NTP time */ 42 43 REQUIRE(jt != NULL); 44 45 REQUIRE(jt->month <= 13); /* permit month 0..13! */ 46 REQUIRE(jt->monthday <= 32); 47 REQUIRE(jt->yearday <= 366); 48 REQUIRE(jt->hour <= 24); 49 REQUIRE(jt->minute <= MINSPERHR); 50 REQUIRE(jt->second <= SECSPERMIN); 51 52 /* 53 * First convert the date to he corresponding RataDie 54 * number. If yearday is not zero, assume that it contains a 55 * useable value and avoid all calculations involving month 56 * and day-of-month. Do a full evaluation otherwise. 57 */ 58 if (jt->yearday) 59 eraday = ntpcal_year_to_ystart(jt->year) 60 + jt->yearday - 1; 61 else 62 eraday = ntpcal_date_to_rd(jt); 63 64 ntptime = ntpcal_dayjoin(eraday - DAY_NTP_STARTS, 65 ntpcal_etime_to_seconds(jt->hour, jt->minute, 66 jt->second)); 67 return ntptime.d_s.lo; 68 } 69