Added the BLAS Library Check.

Default is, that no BLAS Library is used. With the --enable-blas
option BLAS Library searching is enabled. The default Path is /usr/lib.

With the --with-blas-lib=PATH an optional PATH can be specified.

[[Imported from SVN: r165]]

m4/Makefile.am

@@ -2,6 +2,7 @@
 
 aclocaldir = $(datadir)/aclocal
 aclocal_DATA = albert.m4 \
+               blas.m4 \
                dimension.m4 \
                dune.m4 \
                grape.m4 \

m4/albert.m4

@@ -19,9 +19,7 @@ AC_DEFUN([DUNE_PATH_ALBERT],[
     AC_HELP_STRING([--with-albert=PATH],[directory with Albert inside]))
 
 # also ask for elindex
-  AC_ARG_WITH(albert_elindex,
-            AC_HELP_STRING([--with-albert-elindex=INDEX],
-	      [Albert element index (default is 1)]),,with_albert_elindex=1)
+  AC_ARG_WITH(albert_elindex,AC_HELP_STRING([--with-albert-elindex=INDEX],[Albert element index (default is 1)]),,with_albert_elindex=1)
   AC_SUBST(ALBERT_ELINDEX, $with_albert_elindex)
 
 # store old values

m4/blas.m4

+# $Id$
+# searches for blas header and libs
+
+AC_DEFUN([DUNE_PATH_BLAS],[
+  AC_REQUIRE([AC_PROG_CC])
+  AC_REQUIRE([DUNE_DIMENSION])
+
+  AC_ARG_ENABLE(blas,
+   AC_HELP_STRING([--enable-blas], [enable use of BLAS Library (default is disabled)]),
+    [case "$enableval" in
+      yes)
+        AC_SUBST(HAVE_BLAS, "1")
+        m4_bpatsubst([blas],-,_)_ENABLE=yes
+        ;;
+      no)
+        AC_SUBST(HAVE_BLAS, "0")
+        m4_bpatsubst([blas],-,_)_ENABLE=yes
+      ;;
+    *)
+     ;;
+   esac])
+
+  AC_ARG_WITH(blas,
+    AC_HELP_STRING([--with-blas-lib=PATH],[directory with BLAS Library inside (default=/usr/lib)]) )
+
+# also ask for elindex
+
+# store old values
+ac_save_LDFLAGS="$LDFLAGS"
+ac_save_LIBS="$LIBS"
+LIBS=""
+
+# is --with-blas=bla used?
+if test x$with_blas_lib != x ; then
+    if test -d $with_blas; then
+      # expand tilde / other stuff
+      BLASROOT=`cd $with_blas_lib && pwd`
+    else
+      AC_MSG_ERROR([directory $with_blas does not exist])
+    fi      
+else
+  # use some default value...
+  BLASROOT="/usr/lib"
+fi
+
+BLAS_LIB_PATH="$BLASROOT"
+
+# set variables so that tests can use them
+LDFLAGS="$LDFLAGS -L$BLAS_LIB_PATH"
+
+# no header check for blas, because no headers found
+
+if test x$HAVE_BLAS = x1 ; then
+  AC_LANG_PUSH(Fortran 77)
+  AC_CHECK_LIB(blas, [dnrm2],
+               [BLAS_LIBS="-lblas"
+                BLAS_LDFLAGS="-L$BLAS_LIB_PATH"
+                AC_DEFINE(HAVE_LIBBLAS, 1, [Define to 1 if you have libblas])],
+               [AC_MSG_ERROR([Required BLAS library was not found])])
+  AC_LANG_POP(Fortran 77)
+fi
+
+# survived all tests?
+if test x$HAVE_BLAS = x1 ; then
+  echo "*****  BLAS Library found in $BLAS_LIB_PATH"
+  AC_SUBST(BLAS_LIBS, $BLAS_LIBS)
+  AC_SUBST(BLAS_LDFLAGS, $BLAS_LDFLAGS)
+  AC_SUBST(BLAS_CPPFLAGS, $BLAS_CPPFLAGS)
+  AC_DEFINE(HAVE_BLAS, 1, [Define to 1 if blas-library is found])
+
+  # add to global list
+  DUNE_PKG_LDFLAGS="$DUNE_PKG_LDFLAGS $BLAS_LDFLAGS"
+  DUNE_PKG_LIBS="$DUNE_PKG_LIBS $BLAS_LIBS"
+else
+  echo "*****  no BLAS Library is uesd. Enable with the --enable-blas option." 
+  AC_SUBST(BLAS_LIBS, "")
+  AC_SUBST(BLAS_LDFLAGS, "")
+fi
+  
+# also tell automake
+AM_CONDITIONAL(BLAS, test x$HAVE_BLAS = x1)
+
+# reset old values
+LIBS="$ac_save_LIBS"
+LDFLAGS="$ac_save_LDFLAGS"
+
+])