AC_DEFUN([LX_CHECK_CPLEX],

[

  AC_ARG_WITH([cplex],

AS_HELP_STRING([--with-cplex@<:@=PREFIX@:>@], [search for CPLEX under PREFIX or under the default search paths if PREFIX is not given @<:@default@:>@])

AS_HELP_STRING([--without-cplex], [disable checking for CPLEX]),

              [], [with_cplex=yes])

  AC_ARG_WITH([cplex-includedir],

AS_HELP_STRING([--with-cplex-includedir=DIR], [search for CPLEX headers in DIR]),

              [], [with_cplex_includedir=no])

  AC_ARG_WITH([cplex-libdir],

AS_HELP_STRING([--with-cplex-libdir=DIR], [search for CPLEX libraries in DIR]),

              [], [with_cplex_libdir=no])

  lx_cplex_found=no

  if test x"$with_cplex" != x"no"; then

    AC_MSG_CHECKING([for CPLEX])

    if test x"$with_cplex_includedir" != x"no"; then

      CPLEX_CFLAGS="-I$with_cplex_includedir"

    elif test x"$with_cplex" != x"yes"; then

      CPLEX_CFLAGS="-I$with_cplex/include"

    elif test x"$CPLEX_INCLUDEDIR" != x; then

      CPLEX_CFLAGS="-I$CPLEX_INCLUDEDIR"

    fi

    if test x"$with_cplex_libdir" != x"no"; then

      CPLEX_LDFLAGS="-L$with_cplex_libdir"

    elif test x"$with_cplex" != x"yes"; then

      CPLEX_LDFLAGS="-L$with_cplex/lib"

    elif test x"$CPLEX_LIBDIR" != x; then

      CPLEX_LDFLAGS="-L$CPLEX_LIBDIR"

    fi

    CPLEX_LIBS="-lcplex -lm -lpthread"

    lx_save_cxxflags="$CXXFLAGS"

    lx_save_ldflags="$LDFLAGS"

    lx_save_libs="$LIBS"

    CXXFLAGS="$CPLEX_CFLAGS"

    LDFLAGS="$CPLEX_LDFLAGS"

    LIBS="$CPLEX_LIBS"

    lx_cplex_test_prog='

      extern "C" {

      #include <ilcplex/cplex.h>

      }

      int main(int argc, char** argv)

      {

        CPXENVptr env = NULL;

        return 0;

      }'

    AC_LANG_PUSH(C++)

    AC_LINK_IFELSE([$lx_cplex_test_prog], [lx_cplex_found=yes], [lx_cplex_found=no])

    AC_LANG_POP(C++)

    CXXFLAGS="$lx_save_cxxflags"

    LDFLAGS="$lx_save_ldflags"

    LIBS="$lx_save_libs"

    if test x"$lx_cplex_found" = x"yes"; then

      AC_DEFINE([LEMON_HAVE_CPLEX], [1], [Define to 1 if you have CPLEX.])

      AC_MSG_RESULT([yes])

    else

      CPLEX_CFLAGS=""

      CPLEX_LDFLAGS=""

      CPLEX_LIBS=""

      AC_MSG_RESULT([no])

    fi

  fi

  CPLEX_LIBS="$CPLEX_LDFLAGS $CPLEX_LIBS"

  AC_SUBST(CPLEX_CFLAGS)

  AC_SUBST(CPLEX_LIBS)

  AM_CONDITIONAL([HAVE_CPLEX], [test x"$lx_cplex_found" = x"yes"])

])