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#include "sofa.h"
#include <string.h>
int iauDtf2d(const char *scale, int iy, int im, int id,
int ihr, int imn, double sec, double *d1, double *d2)
/*
** - - - - - - - - -
** i a u D t f 2 d
** - - - - - - - - -
**
** Encode date and time fields into 2-part Julian Date (or in the case
** of UTC a quasi-JD form that includes special provision for leap
** seconds).
**
** This function is part of the International Astronomical Union's
** SOFA (Standards of Fundamental Astronomy) software collection.
**
** Status: support function.
**
** Given:
** scale char[] time scale ID (Note 1)
** iy,im,id int year, month, day in Gregorian calendar (Note 2)
** ihr,imn int hour, minute
** sec double seconds
**
** Returned:
** d1,d2 double 2-part Julian Date (Notes 3,4)
**
** Returned (function value):
** int status: +3 = both of next two
** +2 = time is after end of day (Note 5)
** +1 = dubious year (Note 6)
** 0 = OK
** -1 = bad year
** -2 = bad month
** -3 = bad day
** -4 = bad hour
** -5 = bad minute
** -6 = bad second (<0)
**
** Notes:
**
** 1) scale identifies the time scale. Only the value "UTC" (in upper
** case) is significant, and enables handling of leap seconds (see
** Note 4).
**
** 2) For calendar conventions and limitations, see iauCal2jd.
**
** 3) The sum of the results, d1+d2, is Julian Date, where normally d1
** is the Julian Day Number and d2 is the fraction of a day. In the
** case of UTC, where the use of JD is problematical, special
** conventions apply: see the next note.
**
** 4) JD cannot unambiguously represent UTC during a leap second unless
** special measures are taken. The SOFA internal convention is that
** the quasi-JD day represents UTC days whether the length is 86399,
** 86400 or 86401 SI seconds. In the 1960-1972 era there were
** smaller jumps (in either direction) each time the linear UTC(TAI)
** expression was changed, and these "mini-leaps" are also included
** in the SOFA convention.
**
** 5) The warning status "time is after end of day" usually means that
** the sec argument is greater than 60.0. However, in a day ending
** in a leap second the limit changes to 61.0 (or 59.0 in the case
** of a negative leap second).
**
** 6) The warning status "dubious year" flags UTCs that predate the
** introduction of the time scale or that are too far in the future
** to be trusted. See iauDat for further details.
**
** 7) Only in the case of continuous and regular time scales (TAI, TT,
** TCG, TCB and TDB) is the result d1+d2 a Julian Date, strictly
** speaking. In the other cases (UT1 and UTC) the result must be
** used with circumspection; in particular the difference between
** two such results cannot be interpreted as a precise time
** interval.
**
** Called:
** iauCal2jd Gregorian calendar to JD
** iauDat delta(AT) = TAI-UTC
** iauJd2cal JD to Gregorian calendar
**
** This revision: 2013 July 26
**
** SOFA release 2020-07-21
**
** Copyright (C) 2020 IAU SOFA Board. See notes at end.
*/
{
int js, iy2, im2, id2;
double dj, w, day, seclim, dat0, dat12, dat24, dleap, time;
/* Today's Julian Day Number. */
js = iauCal2jd(iy, im, id, &dj, &w);
if ( js ) return js;
dj += w;
/* Day length and final minute length in seconds (provisional). */
day = DAYSEC;
seclim = 60.0;
/* Deal with the UTC leap second case. */
if ( ! strcmp(scale,"UTC") ) {
/* TAI-UTC at 0h today. */
js = iauDat(iy, im, id, 0.0, &dat0);
if ( js < 0 ) return js;
/* TAI-UTC at 12h today (to detect drift). */
js = iauDat(iy, im, id, 0.5, &dat12);
if ( js < 0 ) return js;
/* TAI-UTC at 0h tomorrow (to detect jumps). */
js = iauJd2cal ( dj, 1.5, &iy2, &im2, &id2, &w);
if ( js ) return js;
js = iauDat(iy2, im2, id2, 0.0, &dat24);
if ( js < 0 ) return js;
/* Any sudden change in TAI-UTC between today and tomorrow. */
dleap = dat24 - (2.0*dat12 - dat0);
/* If leap second day, correct the day and final minute lengths. */
day += dleap;
if ( ihr == 23 && imn == 59 ) seclim += dleap;
/* End of UTC-specific actions. */
}
/* Validate the time. */
if ( ihr >= 0 && ihr <= 23 ) {
if ( imn >= 0 && imn <= 59 ) {
if ( sec >= 0 ) {
if ( sec >= seclim ) {
js += 2;
}
} else {
js = -6;
}
} else {
js = -5;
}
} else {
js = -4;
}
if ( js < 0 ) return js;
/* The time in days. */
time = ( 60.0 * ( (double) ( 60 * ihr + imn ) ) + sec ) / day;
/* Return the date and time. */
*d1 = dj;
*d2 = time;
/* Status. */
return js;
/*----------------------------------------------------------------------
**
** Copyright (C) 2020
** Standards Of Fundamental Astronomy Board
** of the International Astronomical Union.
**
** =====================
** SOFA Software License
** =====================
**
** NOTICE TO USER:
**
** BY USING THIS SOFTWARE YOU ACCEPT THE FOLLOWING SIX TERMS AND
** CONDITIONS WHICH APPLY TO ITS USE.
**
** 1. The Software is owned by the IAU SOFA Board ("SOFA").
**
** 2. Permission is granted to anyone to use the SOFA software for any
** purpose, including commercial applications, free of charge and
** without payment of royalties, subject to the conditions and
** restrictions listed below.
**
** 3. You (the user) may copy and distribute SOFA source code to others,
** and use and adapt its code and algorithms in your own software,
** on a world-wide, royalty-free basis. That portion of your
** distribution that does not consist of intact and unchanged copies
** of SOFA source code files is a "derived work" that must comply
** with the following requirements:
**
** a) Your work shall be marked or carry a statement that it
** (i) uses routines and computations derived by you from
** software provided by SOFA under license to you; and
** (ii) does not itself constitute software provided by and/or
** endorsed by SOFA.
**
** b) The source code of your derived work must contain descriptions
** of how the derived work is based upon, contains and/or differs
** from the original SOFA software.
**
** c) The names of all routines in your derived work shall not
** include the prefix "iau" or "sofa" or trivial modifications
** thereof such as changes of case.
**
** d) The origin of the SOFA components of your derived work must
** not be misrepresented; you must not claim that you wrote the
** original software, nor file a patent application for SOFA
** software or algorithms embedded in the SOFA software.
**
** e) These requirements must be reproduced intact in any source
** distribution and shall apply to anyone to whom you have
** granted a further right to modify the source code of your
** derived work.
**
** Note that, as originally distributed, the SOFA software is
** intended to be a definitive implementation of the IAU standards,
** and consequently third-party modifications are discouraged. All
** variations, no matter how minor, must be explicitly marked as
** such, as explained above.
**
** 4. You shall not cause the SOFA software to be brought into
** disrepute, either by misuse, or use for inappropriate tasks, or
** by inappropriate modification.
**
** 5. The SOFA software is provided "as is" and SOFA makes no warranty
** as to its use or performance. SOFA does not and cannot warrant
** the performance or results which the user may obtain by using the
** SOFA software. SOFA makes no warranties, express or implied, as
** to non-infringement of third party rights, merchantability, or
** fitness for any particular purpose. In no event will SOFA be
** liable to the user for any consequential, incidental, or special
** damages, including any lost profits or lost savings, even if a
** SOFA representative has been advised of such damages, or for any
** claim by any third party.
**
** 6. The provision of any version of the SOFA software under the terms
** and conditions specified herein does not imply that future
** versions will also be made available under the same terms and
** conditions.
*
** In any published work or commercial product which uses the SOFA
** software directly, acknowledgement (see www.iausofa.org) is
** appreciated.
**
** Correspondence concerning SOFA software should be addressed as
** follows:
**
** By email: sofa@ukho.gov.uk
** By post: IAU SOFA Center
** HM Nautical Almanac Office
** UK Hydrographic Office
** Admiralty Way, Taunton
** Somerset, TA1 2DN
** United Kingdom
**
**--------------------------------------------------------------------*/
}