configure.ac: Add a --without-contrib option

configure.ac

@@ -73,12 +73,16 @@ AC_C_INLINE
 dnl
 dnl  Check for the contrib directory
 dnl
-topdir="`dirname $0`"
-if test "`echo \"$topdir\" | cut -c 1`" != "/"; then
+AC_ARG_WITH(contrib,
+    [  --without-contrib       do not use the libraries in extras/contrib],[],[])
+  if test "${with_contrib}" != "no"; then 
+
+    topdir="`dirname $0`"
+    if test "`echo \"$topdir\" | cut -c 1`" != "/"; then
        topdir="`pwd`/$topdir"
-fi
+    fi
 
-if test -d ${topdir}/extras/contrib/lib; then
+  if test -d ${topdir}/extras/contrib/lib; then
     export PATH=${topdir}/extras/contrib/bin:$PATH
     CPPFLAGS="${CPPFLAGS} -I${topdir}/extras/contrib/include"
     CPPFLAGS_save="${CPPFLAGS_save} -I${topdir}/extras/contrib/include"
@@ -103,8 +107,8 @@ if test -d ${topdir}/extras/contrib/lib; then
       export LIBRARY_PATH=${topdir}/extras/contrib/lib:$LIBRARY_PATH
       export BELIBRARIES=${topdir}/extras/contrib/lib:$BELIBRARIES
     fi
+  fi
 fi
-
 dnl
 dnl  Set default values
 dnl