dnl -*- shell-script -*-
dnl
dnl Copyright (c) 2004-2005 The Trustees of Indiana University and Indiana
dnl                         University Research and Technology
dnl                         Corporation.  All rights reserved.
dnl Copyright (c) 2004-2005 The University of Tennessee and The University
dnl                         of Tennessee Research Foundation.  All rights
dnl                         reserved.
dnl Copyright (c) 2004-2005 High Performance Computing Center Stuttgart, 
dnl                         University of Stuttgart.  All rights reserved.
dnl Copyright (c) 2004-2005 The Regents of the University of California.
dnl                         All rights reserved.
dnl $COPYRIGHT$
dnl 
dnl Additional copyrights may follow
dnl 
dnl $HEADER$
dnl


AC_DEFUN([OMPI_F77_FIND_EXT_SYMBOL_CONVENTION], [
    AC_REQUIRE([AC_PROG_NM])
    AC_REQUIRE([AC_PROG_GREP])

    # invalidate cache if result came from a run where F77 was disabled
    if test "$ompi_cv_f77_external_symbol" = "skipped" ; then
        unset ompi_cv_f77_external_symbol
    fi

    AC_CACHE_CHECK([$F77 external symbol convention],
        [ompi_cv_f77_external_symbol],
        [if test "$F77" = "none" -o "$OMPI_WANT_F77_BINDINGS" = "0"; then
             ompi_cv_f77_external_symbol="skipped"
         else
             cat >conftest.f <<EOF
       subroutine FOO_bar(a)
       integer a
       a = 1
       return
       end
EOF
             OMPI_LOG_COMMAND([$F77 $FFLAGS -c conftest.f $LDFLAGS $LIBS],
                 [if $NM conftest.o | $GREP foo_bar__ >/dev/null 2>&1 ; then
                      ompi_cv_f77_external_symbol="double underscore"
                  elif $NM conftest.o | $GREP foo_bar_ >/dev/null 2>&1 ; then
                      ompi_cv_f77_external_symbol="single underscore"
                  elif $NM conftest.o | $GREP FOO_bar >/dev/null 2>&1 ; then
                      ompi_cv_f77_external_symbol="mixed case"
                  elif $NM conftest.o | $GREP foo_bar >/dev/null 2>&1 ; then
                      ompi_cv_f77_external_symbol="no underscore"
                  elif $NM conftest.o | $GREP FOO_BAR >/dev/null 2>&1 ; then
                      ompi_cv_f77_external_symbol="upper case"
                  else
                      $NM conftest.o >conftest.out 2>&1
                      OMPI_LOG_MSG([output from $NM:])
                      OMPI_LOG_FILE([conftest.out])
                      AC_MSG_ERROR([Could not determine Fortran naming convention.])
                  fi],
                 [AC_MSG_ERROR([Fortran compiler did not produce object file])])
         fi])

    ompi_fortran_double_underscore=0
    ompi_fortran_single_underscore=0
    ompi_fortran_caps=0
    ompi_fortran_plain=0

    if test "$ompi_cv_f77_external_symbol" = "double underscore" ; then
        ompi_fortran_double_underscore=1
    elif test "$ompi_cv_f77_external_symbol" = "single underscore" ; then
        ompi_fortran_single_underscore=1
    elif test "$ompi_cv_f77_external_symbol" = "mixed case" ; then
        ompi_fortran_caps=1
    elif test "$ompi_cv_f77_external_symbol" = "no underscore" ; then
        ompi_fortran_plain=1
    elif test "$ompi_cv_f77_external_symbol" = "upper case" ; then
        ompi_fortran_caps=1
    elif test "$ompi_cv_f77_external_symbol" != "skipped" ; then
        AC_MSG_ERROR([unknown naming convention: $ompi_cv_f77_external_symbol])
    fi

    AC_DEFINE_UNQUOTED([OMPI_F77_DOUBLE_UNDERSCORE],
        [$ompi_fortran_double_underscore], 
        [Whether fortran symbols have a trailing double underscore or not])
    AC_DEFINE_UNQUOTED([OMPI_F77_SINGLE_UNDERSCORE], 
        [$ompi_fortran_single_underscore],
        [Whether fortran symbols have a trailing underscore or not])
    AC_DEFINE_UNQUOTED([OMPI_F77_CAPS],
        [$ompi_fortran_caps],
        [Whether fortran symbols are all caps or not])
    AC_DEFINE_UNQUOTED([OMPI_F77_PLAIN], 
        [$ompi_fortran_plain],
        [Whether fortran symbols have no trailing underscore or not])

    rm -f conftest.*
])dnl


AC_DEFUN([OMPI_F77_MAKE_C_FUNCTION], [
    if test "$ompi_cv_f77_external_symbol" = "double underscore" ; then
        # so the general rule is that if there is an _ in the function
        # name, then there are two trailing underscores.  Otherwise,
        # there is only one trailing underscore.  Any idea how to do
        # that with m4_translit?
        if echo $2 | $GREP _ >/dev/null 2>&1 ; then
            $1[=]m4_translit([$2], [A-Z], [a-z])[__]
        else
            $1[=]m4_translit([$2], [A-Z], [a-z])[_]
        fi
    elif test "$ompi_cv_f77_external_symbol" = "single underscore" ; then
        $1[=]m4_translit([$2], [A-Z], [a-z])[_]
    elif test "$ompi_cv_f77_external_symbol" = "mixed case" ; then
        $1[=]$2
    elif test "$ompi_cv_f77_external_symbol" = "no underscore" ; then
        $1[=]m4_translit([$2], [A-Z], [a-z])
    elif test "$ompi_cv_f77_external_symbol" = "upper case" ; then
        $1[=]m4_translit([$2], [a-z], [A-Z])
    else
        AC_MSG_ERROR([unknown naming convention: $ompi_cv_f77_external_symbol])
    fi
])