ENH: split up internals of wmake/scripts/have_XXX functions

- adds some more flexibility

wmake/scripts/have_metis

@@ -20,7 +20,7 @@
 #     config.sh/metis
 #
 # Functions provided
-#     have_metis, no_metis, echo_metis, query_metis
+#     have_metis, no_metis, echo_metis, query_metis, search_metis
 #
 # Variables set on success
 #     HAVE_METIS
@@ -33,7 +33,7 @@
 
 #------------------------------------------------------------------------------
 
-# Reset variables
+# Reset
 no_metis()
 {
     unset HAVE_METIS METIS_ARCH_PATH METIS_INC_DIR METIS_LIB_DIR
@@ -51,43 +51,18 @@ echo_metis()
 }
 
 
-# Query settings
-query_metis()
-{
-    local config="config.sh/metis"
-    local settings
-
-    if settings="$("$WM_PROJECT_DIR"/bin/foamEtcFile -mode=o "$config")"
-    then
-        . "$settings"
-        _process_query metis "$METIS_ARCH_PATH"
-    else
-        echo "(no $config settings)" 1>&2
-        echo "metis=unknown"
-    fi
-}
-
-
+# Search
+# $1 : prefix (*_ARCH_PATH, system, ...)
+#
 # On success, return 0 and export variables
 # -> HAVE_METIS, METIS_ARCH_PATH, METIS_INC_DIR, METIS_LIB_DIR
-have_metis()
+search_metis()
 {
     local warn="==> skip metis"
-    local config="config.sh/metis"
-    local settings
-
-    if settings="$("$WM_PROJECT_DIR"/bin/foamEtcFile "$config")"
-    then
-        . "$settings"
-    else
-        [ -n "$warn" ] && echo "$warn (no $config settings)"
-        return 2
-    fi
-
-    # Expected location, include/library names
-    local prefix="$METIS_ARCH_PATH"
     local incName="metis.h"
     local libName="libmetis"
+
+    local prefix="${1:-system}"
     local header library
 
     # ----------------------------------
@@ -142,6 +117,44 @@ have_metis()
 }
 
 
+# Output as per search_* function
+have_metis()
+{
+    local warn="==> skip metis"
+    local config="config.sh/metis"
+    local file
+
+    if file="$("$WM_PROJECT_DIR"/bin/foamEtcFile "$config")"
+    then
+        . "$file"
+    else
+        [ -n "$warn" ] && echo "$warn (no $config)"
+        return 2
+    fi
+
+    search_metis "$METIS_ARCH_PATH"
+}
+
+
+# Query settings
+query_metis()
+{
+    local config="config.sh/metis"
+    local file
+
+    if file="$("$WM_PROJECT_DIR"/bin/foamEtcFile -mode=o "$config")"
+    then
+        . "$file"
+        _process_query metis "$METIS_ARCH_PATH"
+    else
+        echo "(no $config)" 1>&2
+        echo "metis=unknown"
+    fi
+}
+
+
+#------------------------------------------------------------------------------
+
 # Reset variables
 no_metis