Updated ErrorBuffer.

* Removed the JRuby workaround since it has been fixed.
  http://jira.codehaus.org/browse/JRUBY-4519

lib/ffi/pcap/error_buffer.rb

@@ -1,32 +1,20 @@
 module FFI
   module PCap
-    class ErrorBuffer < FFI::MemoryPointer
+    class ErrorBuffer < FFI::Buffer
 
       # Size of the error buffers
       SIZE = 256
 
-      #
-      # Creates a new {ErrorBuffer} object. Because of wierdness in JRuby
-      # when trying to subclass `FFI::Buffer`, always use this instead of
-      # {#initialize}.
-      #
-      # @see http://github.com/ffi/ffi/issues#issue/27
-      #
-      def self.create()
-        new(SIZE)
-      end
-
       #
       # Creates a new {ErrorBuffer} object.
       #
-      # @param [Object] nil
-      #   The argument is nil and is only present for compatability with
-      #   JRuby.
-      #
-      # @see http://github.com/ffi/ffi/issues#issue/27
+      # @param [FFI::Pointer] ptr
+      #   Optional pointer to an existing {ErrorBuffer}.
       #
-      def initialize(arg=nil)
-        super(SIZE)
+      def initialize(ptr=nil)
+        if ptr then super(ptr)
+        else        super(SIZE)
+        end
       end
 
       #
@@ -36,18 +24,6 @@ def to_s
         get_string(0)
       end
 
-      #
-      # Older JRuby/ffi versions of MemoryPointer and Buffer don't have a
-      # size method. We override it here to ensure we can use it.
-      #
-      def size
-        begin
-          super()
-        rescue NoMethodError
-          SIZE
-        end
-      end
-
     end
   end
 end

spec/error_buffer_spec.rb

@@ -1,16 +1,14 @@
 require 'spec_helper'
 
 describe ErrorBuffer do
-  subject { ErrorBuffer.create }
-
   it "should have a default size of 256" do
     subject.size.should == 256
   end
 
   it "should return an error message with to_s" do
     subject.to_s.should be_empty
 
-    FFI::PCap.pcap_open_offline("/this/file/wont/exist",subject)
+    PCap.pcap_open_offline("/this/file/wont/exist",subject)
 
     subject.to_s.should_not be_empty
   end