configure.in

AC_INIT(src/Rcart.c)


AC_ARG_WITH(fftw3, [], FFTW3_DIR="$withval")


if test -z "$FFTW3_DIR" ; then
  AC_PATH_PROGS(PKG_CONFIG, pkg-config)
fi


if test -z "$FFTW3_DIR" ; then

 if test -n "$PKG_CONFIG" ; then 
  PKG_CPPFLAGS=`$PKG_CONFIG --cflags fftw3`
  CPPFLAGS=$PKG_CPPFLAGS
  if test $? = 0 ; then
     PKG_LIBS=`$PKG_CONFIG --libs fftw3`
     FOUND_FFTW3="yes"
  fi
 fi
fi


if test -z "$PKG_CPPFLAGS" ; then

  if test -z "$FFTW3_DIR" ; then
    FFTW3_DIR=/usr/local
  fi

  echo "Looking for fftw3 files in $FFTW3_DIR"
  
   # User specified this with --with-fftw3 or setting the environment
   # variable FFTW3_DIR
   # So see if the fftw3.h is there.
  if test -r $FFTW3_DIR/include/fftw3.h ; then
     PKG_CPPFLAGS="-I$FFTW3_DIR/include/"
  elif test -r $FFTW3_DIR/api/fftw3.h ; then
     PKG_CPPFLAGS="-I$FFTW3_DIR/api"
  else
     echo "Cannot find fftw.h"
     exit 10
  fi

  CPPFLAGS="$PKG_CPPFLAGS"
  FOUND_FFTW3="yes"
fi  



dnl Now check we can compile and link.

AC_TRY_COMPILE([#include <fftw3.h>],
                 [
                  fftw_plan plan;
                 ], [echo "Can compile with fftw3.h"], [AC_MSG_ERROR("cannot find fftw3.h header file") ; exit 1])

AC_CHECK_LIB(fftw3, fftw_malloc, , [AC_MSG_ERROR("cannot link to libfftw3"); exit 2])



if test -z "$PKG_LIBS" ; then
  LIBS="-L$FFTW3_DIR/lib -lfftw3"
  if  ! test -d "$FFTW3_DIR/lib" ; then
     LIBS="-L$FFTW3_DIR/.libs -lfftw3"
  fi
else
  LIBS="$PKG_LIBS"
fi


 echo "Trying to link against libfftw3"

  AC_TRY_LINK([#include <fftw3.h>],
              [    fftw_plan plan;
                   fftw_destroy_plan(plan);
              ],
                [PKG_LIBS="$LIBS -lfftw3"; echo "Can link against libfftw3"],
                [echo "Cannot find/link against libfftw3 in $LIBS"; exit 11;]
           )


DEFINES="-DNOPROGRESS"

PKG_CPPFLAGS="$PKG_CPPFLAGS $DEFINES"

if test -z "$PKG_LIBS" ; then
  echo "Cannot find how to link against libfftw3. If it is installed, please contact duncan@wald.ucdavis.edu"
  echo "so that the configuration script for this package can be improved.  If it is not installed, please install it."
  exit 1;
fi

AC_SUBST(PKG_CPPFLAGS)
AC_SUBST(PKG_LIBS)

AC_OUTPUT(src/Makevars)