Switch to ERFA

Routines are now written to use ERFA natively but can be switched
to SOFA using a C define. The configure script will check for
both ERFA and SOFA.

Makefile.am

@@ -7,11 +7,11 @@ lib_LTLIBRARIES = libpal.la
 libpal_la_SOURCES = $(PUBLIC_C_FILES) palOne2One.c $(PRIVATE_C_FILES)
 
 # If we are using a non-standard location
-libpal_la_CPPFLAGS = $(SOFA_CPPFLAGS)
-libpal_la_LDFLAGS = $(SOFA_LDFLAGS)
+libpal_la_CPPFLAGS = $(ERFA_CPPFLAGS)
+libpal_la_LDFLAGS = $(ERFA_LDFLAGS)
 
-# Force a link against SOFA and, optionally, starutil
-libpal_la_LIBADD = $(SOFA_LIBADD) $(STARUTIL_LIBADD)
+# Force a link against ERFA and, optionally, starutil
+libpal_la_LIBADD = $(ERFA_LIBADD) $(STARUTIL_LIBADD)
 
 # Misc files
 dist_starnews_DATA = pal.news

README.md

@@ -3,7 +3,8 @@ PAL - Positional Astronomy Library
 
 The PAL library is a partial re-implementation of Pat Wallace's popular SLALIB
 library written in C using a Gnu GPL license and layered on top of the IAU's
-SOFA library where appropriate. PAL attempts to stick to the SLA C API where
+SOFA library (or the BSD-licensed ERFA) where appropriate.
+PAL attempts to stick to the SLA C API where
 possible although `palObs()` has a more C-like API than the equivalent
 `slaObs()` function. In most cases it is enough to simply change the function
 prefix of a routine in order to link against PAL rather than SLALIB. Routines
@@ -24,14 +25,18 @@ A simple `configure` script is provided:
     make install
 
 The tests can be run using `make check`. Use `--prefix` to specify an install location.
-Given the history of the source code as a Starlink libary the default will be `/star`.
+Given the history of the source code as a Starlink library the default will be `/star`.
 
 Requirements
 ------------
 
-Requires that the SOFA C library is installed. The `configure` script will abort if SOFA
-can not be found. SOFA can be obtained either from <http://www.iausofa.org> or from
-an unofficial github repository (with a configure script) at <https://github.com/Starlink/sofa/downloads>.
+Requires that either the SOFA C library or the ERFA library variant
+(which has a more permissive license than SOFA) be installed.  The
+`configure` script will abort if neither SOFA nor ERFA can be
+found. SOFA can be obtained either from <http://www.iausofa.org> or
+from an unofficial github repository (with a configure script) at
+<https://github.com/Starlink/sofa/downloads>.  ERFA can be downloaded
+from <https://github.com/liberfa/erfa>.
 
 Missing Functions
 -----------------

component.xml

@@ -3,7 +3,7 @@
 <!-- component.xml.  Generated from component.xml.in by configure. -->
 
 <component id="pal" support="S">
-  <version>0.4.0</version>
+  <version>0.5.0</version>
   <path>libext/pal</path>
   <description>Positional Astronomy Library</description>
   <abstract><p>

configure.ac

@@ -2,7 +2,7 @@ dnl    Process this file with autoconf to produce a configure script
 AC_REVISION($Revision: 27534 $)
 
 dnl    Initialisation: package name and version number
-AC_INIT([pal],[0.4.0],[[email protected]])
+AC_INIT([pal],[0.5.0],[[email protected]])
 
 dnl    Require autoconf-2.50 at least
 AC_PREREQ([2.69])
@@ -43,8 +43,8 @@ dnl    If we do not have Starlink we can do the test anyhow just in case
 if test -n "$STARLINK"
 then
   AC_SUBST( STARUTIL_LIBADD, "${libdir}/libstarutil.la" )
-  AC_SUBST( SOFA_LIBADD, "${libdir}/libsofa_c.la" )
-  AC_SUBST( SOFA_LDFLAGS, "" )
+  AC_SUBST( ERFA_LIBADD, "${libdir}/liberfa.la" )
+  AC_SUBST( ERFA_LDFLAGS, "" )
   AC_DEFINE( [HAVE_STAR_UTIL_H], [1], [Define to 1 if you have the <star/util.h> header file])
 else
   dnl AC_CHECK_HEADERS does not search $includedir
@@ -65,14 +65,19 @@ else
                [AC_SUBST(STARUTIL_LIBADD, "-lstarutil")],
                [AC_SUBST(STARUTIL_LIBADD, "")])
 
-  AC_CHECK_LIB([sofa_c],[iauCal2jd],
-               [AC_SUBST(SOFA_LIBADD, "-lsofa_c")],
-               [AC_MSG_ERROR(Missing SOFA library. Can not continue)])
+  AC_CHECK_LIB([erfa],[eraCal2jd],
+               [AC_SUBST(ERFA_LIBADD, "-lerfa")],
+               [
+                AC_CHECK_LIB([sofa_c],[iauCal2jd],
+                             [AC_SUBST(ERFA_LIBADD, "-lsofa_c")
+                              AC_DEFINE([HAVE_SOFA_H],[1],"Build with SOFA library")],
+                             [AC_MSG_ERROR(Neither ERFA nor SOFA library located. Can not continue)])
+               ])
   LDFLAGS="$save_LDFLAGS"
 
   dnl  Ensure that we use the $prefix values
-  AC_SUBST( SOFA_LDFLAGS, "-L${libdir}" )
-  AC_SUBST( SOFA_CPPFLAGS, "-I${includedir}" )
+  AC_SUBST( ERFA_LDFLAGS, "-L${libdir}" )
+  AC_SUBST( ERFA_CPPFLAGS, "-I${includedir}" )
 
   dnl  Disable document building regardless of --without-stardocs
   _star_build_docs=:

pal.news

@@ -4,6 +4,12 @@ The Starlink Positional Astronomy Library (PAL) is a C implementation of the
 SLALIB API. It is distributed under the GPL and uses the SOFA library wherever
 possible.
 
+V0.5.0
+
+Now works with ERFA <https://github.com/liberfa/erfa>.
+The configure script has been modified to first check
+for ERFA and then check for SOFA.
+
 V0.4.0
 
 New routines ported from SLA: palRefv, palAtmdsp

pal1sofa.h

@@ -0,0 +1,140 @@
+/*
+*+
+*  Name:
+*     pal1sofa.h
+
+*  Purpose:
+*     Mappings of ERFA names to SOFA names
+
+*  Language:
+*     Starlink ANSI C
+
+*  Type of Module:
+*     Include file
+
+*  Invocation:
+*     #include "pal1.h"
+
+*  Description:
+*     PAL will work with both SOFA and ERFA libraries and the
+*     difference is generally a change in prefix. This include
+*     file maps the ERFA form of functions to the SOFA form
+*     and includes the relevant sofa.h vs erfa.h file.
+
+*  Authors:
+*     TIMJ: Tim Jenness (JAC, Hawaii)
+*     {enter_new_authors_here}
+
+*  Notes:
+*     - PAL uses the ERFA form by default.
+
+*  History:
+*     2014-07-29 (TIMJ):
+*        Initial version
+*     {enter_further_changes_here}
+
+*  Copyright:
+*     Copyright (C) 2014 Tim Jenness
+*     All Rights Reserved.
+
+*  Licence:
+*     This program is free software; you can redistribute it and/or
+*     modify it under the terms of the GNU General Public License as
+*     published by the Free Software Foundation; either version 3 of
+*     the License, or (at your option) any later version.
+*
+*     This program is distributed in the hope that it will be
+*     useful, but WITHOUT ANY WARRANTY; without even the implied
+*     warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+*     PURPOSE. See the GNU General Public License for more details.
+*
+*     You should have received a copy of the GNU General Public License
+*     along with this program; if not, write to the Free Software
+*     Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+*     MA 02110-1301, USA.
+
+*  Bugs:
+*     {note_any_bugs_here}
+*-
+*/
+
+#ifndef PAL1SOFAHDEF
+#define PAL1SOFAHDEF
+
+#include <config.h>
+
+# if HAVE_SOFA_H
+
+#  include "sofa.h"
+#  include "sofam.h"
+
+   /* Must replace ERFA with SOFA */
+
+#  define eraA2af iauA2af
+#  define eraA2tf iauA2tf
+#  define eraAf2a iauAf2a
+#  define eraAnp iauAnp
+#  define eraAnpm iauAnpm
+#  define eraC2s iauC2s
+#  define eraCal2jd iauCal2jd
+#  define eraD2tf iauD2tf
+#  define eraDat iauDat
+#  define eraEe06a iauEe06a
+#  define eraEpb iauEpb
+#  define eraEpb2jd iauEpb2jd
+#  define eraEpj iauEpj
+#  define eraEpj2jd iauEpj2jd
+#  define eraEpv00 iauEpv00
+#  define eraFk5hz iauFk5hz
+#  define eraGd2gc iauGd2gc
+#  define eraGmst06 iauGmst06
+#  define eraHfk5z iauHfk5z
+#  define eraIr iauIr
+#  define eraJd2cal iauJd2cal
+#  define eraNut06a iauNut06a
+#  define eraObl06 iauObl06
+#  define eraP06e iauP06e
+#  define eraPap iauPap
+#  define eraPas iauPas
+#  define eraPdp iauPdp
+#  define eraPlan94 iauPlan94
+#  define eraPmat06 iauPmat06
+#  define eraPn iauPn
+#  define eraPnm06a iauPnm06a
+#  define eraPxp iauPxp
+#  define eraRefco iauRefco
+#  define eraRm2v iauRm2v
+#  define eraRv2m iauRv2m
+#  define eraRx iauRx
+#  define eraRxp iauRxp
+#  define eraRxpv iauRxpv
+#  define eraRxr iauRxr
+#  define eraRy iauRy
+#  define eraRz iauRz
+#  define eraS2c iauS2c
+#  define eraSepp iauSepp
+#  define eraSeps iauSeps
+#  define eraStarpm iauStarpm
+#  define eraTf2a iauTf2a
+#  define eraTf2d iauTf2d
+#  define eraTr iauTr
+#  define eraTrxp iauTrxp
+
+/* These are from sofam.h */
+
+#  define ERFA_WGS84 WGS84
+
+#  define ERFA_DJ00 DJ00
+#  define ERFA_DJY DJY
+#  define ERFA_DAU DAU
+
+# else
+
+#  include "erfa.h"
+#  include "erfam.h"
+
+/* No further action required */
+
+# endif
+
+#endif

palAddet.c

@@ -83,7 +83,7 @@
 */
 
 #include "pal.h"
-#include "sofa.h"
+#include "pal1sofa.h"
 
 void palAddet ( double rm, double dm, double eq, double *rc, double *dc ) {
   double a[3];   /* The E-terms */
@@ -96,17 +96,17 @@ void palAddet ( double rm, double dm, double eq, double *rc, double *dc ) {
   palEtrms( eq, a );
 
   /* Spherical to Cartesian */
-  iauS2c( rm, dm, v );
+  eraS2c( rm, dm, v );
 
   /* Include the E-terms */
   for (i=0; i<3; i++) {
     v[i] += a[i];
   }
 
   /* Cartesian to spherical */
-  iauC2s( v, rc, dc );
+  eraC2s( v, rc, dc );
 
   /* Bring RA into conventional range */
-  *rc = iauAnp( *rc );
+  *rc = eraAnp( *rc );
 
 }

palAmpqk.c

@@ -80,7 +80,7 @@
 */
 
 #include "pal.h"
-#include "sofa.h"
+#include "pal1sofa.h"
 
 void palAmpqk ( double ra, double da, double amprms[21], double *rm,
                 double *dm ){
@@ -99,30 +99,30 @@ void palAmpqk ( double ra, double da, double amprms[21], double *rm,
    }
 
 /* Apparent RA,Dec to Cartesian */
-   iauS2c( ra, da, p3 );
+   eraS2c( ra, da, p3 );
 
 /* Precession and nutation */
-   iauTrxp( (double(*)[3]) &amprms[12], p3, p2 );
+   eraTrxp( (double(*)[3]) &amprms[12], p3, p2 );
 
 /* Aberration */
    ab1p1 = ab1 + 1.0;
    for( i = 0; i < 3; i++ ) {
       p1[i] = p2[i];
    }
    for( j = 0; j < 2; j++ ) {
-      p1dv = iauPdp( p1, abv );
+      p1dv = eraPdp( p1, abv );
       p1dvp1 = 1.0 + p1dv;
       w = 1.0 + p1dv / ab1p1;
       for( i = 0; i < 3; i++ ) {
          p1[i] = ( p1dvp1 * p2[i] - w * abv[i] ) / ab1;
       }
-      iauPn( p1, &w, p3 );
+      eraPn( p1, &w, p3 );
       for( i = 0; i < 3; i++ ) {
          p1[i] = p3[i];
       }
    }
 
 /* Mean RA,Dec */
-   iauC2s( p1, rm, dm );
-   *rm = iauAnp( *rm );
+   eraC2s( p1, rm, dm );
+   *rm = eraAnp( *rm );
 }

palCaldj.c

@@ -25,7 +25,7 @@
 *     djm = double * (Returned)
 *        Modified Julian Date (JD-2400000.5) for 0 hrs
 *     j = status (Returned)
-*       0 = OK. See iauCal2jd for other values.
+*       0 = OK. See eraCal2jd for other values.
 
 *  Description:
 *     Modified Julian Date to Gregorian Calendar with special
@@ -43,8 +43,8 @@
 *     {enter_further_changes_here}
 
 *  Notes:
-*     - Uses iauCal2jd
-*     - Unlike iauCal2jd this routine treats the years 0-100 as
+*     - Uses eraCal2jd
+*     - Unlike eraCal2jd this routine treats the years 0-100 as
 *       referring to the end of the 20th Century and beginning of
 *       the 21st Century. If this behaviour is not acceptable
 *       use the SOFA routine directly or palCldj.
@@ -82,7 +82,7 @@
 
 #include "pal.h"
 #include "palmac.h"
-#include "sofa.h"
+#include "pal1sofa.h"
 
 void palCaldj ( int iy, int im, int id, double *djm, int *j ) {
   int adj = 0;   /* Year adjustment */
@@ -95,5 +95,5 @@ void palCaldj ( int iy, int im, int id, double *djm, int *j ) {
   }
   iy += adj;
 
-  *j = iauCal2jd( iy, im, id, &djm0, djm );
+  *j = eraCal2jd( iy, im, id, &djm0, djm );
 }

palDafin.c

@@ -125,7 +125,7 @@
 
 #include "pal.h"
 #include "palmac.h"
-#include "sofam.h"
+#include "pal1sofa.h"
 
 #include <math.h>
 
@@ -171,10 +171,10 @@ void palDafin ( const char *string, int *ipos, double *a, int *j ) {
         jf = -3;
 
       /* Tests for range and integrality */
-      } else if (jm == 0 && dint(deg) != deg) { /* Degrees */
+      } else if (jm == 0 && DINT(deg) != deg) { /* Degrees */
         jf = -1;
 
-      } else if ( (js == 0 && dint(arcmin) != arcmin) || arcmin >= 60.0 ) { /* Arcmin */
+      } else if ( (js == 0 && DINT(arcmin) != arcmin) || arcmin >= 60.0 ) { /* Arcmin */
         jf = -2;
 
       } else if (arcsec >= 60.0) { /* Arcsec */