Factor out list/filter code

lib/netlink/route/handler.rb

@@ -0,0 +1,46 @@
+module Netlink
+  module Route
+    # This class allows objects to be created representing the
+    # conditions given to the 'list' method
+    class BaseFilter #:nodoc:
+      def self.filter name, &blk
+        define_method "#{name}=" do |matchval|
+          @conds << [blk, matchval]
+        end
+      end
+      
+      def initialize(h)
+        @conds = []
+        h.each { |k,v| send "#{k}=", v }
+      end
+      
+      def match(obj)
+        !@conds.find { |blk,matchval| !blk[obj,matchval] }
+      end
+    end
+
+    # Code which is common to all the NETLINK_ROUTE handlers
+    class Handler
+      def initialize(rtsocket = Netlink::Route::Socket.new)
+        @rtsocket = rtsocket
+        clear_cache
+      end
+      
+      def index(v)
+        @rtsocket.index(v)
+      end
+      
+      def ifname(v)
+        @rtsocket.ifname(v)
+      end
+
+      # Generic listing and filtering
+      def do_list(data, filter, &blk)
+        return data.each(&blk) unless filter
+        return to_enum(:list, filter) unless block_given?
+        fm = self.class::Filter.new(filter)
+        data.each { |o| yield o if fm.match(o) }
+      end
+    end
+  end
+end