Add support for mmap (LMC) adapter

lib/moneta/lmc.rb

@@ -0,0 +1,52 @@
+begin
+  require "localmemcache"
+rescue LoadError
+  puts "You need the localmemcache gem to use the LMC moneta store"
+  exit
+end
+
+module Moneta
+  class Expiration
+    def initialize(hash)
+      @hash = hash
+    end
+
+    def [](key)         @hash["#{key}__!__expiration"]          end
+    def []=(key, value) @hash["#{key}__!__expiration"] = value  end
+
+    def delete(key)
+      key = "#{key}__!__expiration"
+      value = @hash[key]
+      @hash.delete(key)
+      value
+    end
+  end
+
+  class LMC
+    include Defaults
+
+    module Implementation
+      def initialize(options = {})
+        @hash = LocalMemCache.new(:filename => options[:filename])
+        @expiration = Expiration.new(@hash)
+      end    
+
+      def [](key)         @hash[key]          end
+      def []=(key, value) @hash[key] = value  end
+      def clear()         @hash.clear         end
+
+      def key?(key)
+        @hash.keys.include?(key)
+      end
+
+      def delete(key)
+        value = @hash[key]
+        @hash.delete(key)
+        value
+      end      
+    end
+    include Implementation
+    include StringExpires
+
+  end
+end

spec/moneta_lmc_spec.rb

@@ -0,0 +1,24 @@
+require File.dirname(__FILE__) + '/spec_helper'
+
+begin
+  require "moneta/lmc"
+  require "fileutils"
+
+  # Problem: If there are multiple caches around, they start
+  # to block (with a system semaphore), which can be unpleasant
+  # so just use one cache for the entire test run.
+  $lmc_cache = Moneta::LMC.new(:filename => "test")
+
+  describe "Moneta::LMC" do
+    before(:all) do
+      @cache = $lmc_cache
+    end
+
+    after(:each) do
+      @cache.clear
+    end
+
+    it_should_behave_like "a read/write Moneta cache"
+  end
+rescue SystemExit
+end