4 files changed, 31 insertions, 14 deletions
diff --git a/actionpack/lib/action_controller/integration.rb b/actionpack/lib/action_controller/integration.rb
index 5b08e30d49..163ba84a3e 100644
--- a/actionpack/lib/action_controller/integration.rb
+++ b/actionpack/lib/action_controller/integration.rb
@@ -2,17 +2,6 @@ require 'stringio'
 require 'uri'
 require 'active_support/test_case'
 
-# Monkey patch Rack::Lint to support rewind
-module Rack
-  class Lint
-    class InputWrapper
-      def rewind
-        @input.rewind
-      end
-    end
-  end
-end
-
 module ActionController
   module Integration #:nodoc:
     # An integration Session instance represents a set of requests and responses
diff --git a/actionpack/lib/action_controller/middleware_stack.rb b/actionpack/lib/action_controller/middleware_stack.rb
index 2bccba2ba1..b94bf6ec4a 100644
--- a/actionpack/lib/action_controller/middleware_stack.rb
+++ b/actionpack/lib/action_controller/middleware_stack.rb
@@ -32,6 +32,8 @@ module ActionController
         else
           @klass.to_s.constantize
         end
+      rescue NameError
+        @klass
       end
 
       def active?
diff --git a/actionpack/lib/action_controller/rack_ext.rb b/actionpack/lib/action_controller/rack_ext.rb
new file mode 100644
index 0000000000..3b142307e9
--- /dev/null
+++ b/actionpack/lib/action_controller/rack_ext.rb
@@ -0,0 +1,22 @@
+module Rack
+  module Utils
+    module Multipart
+      class << self
+        def parse_multipart_with_rewind(env)
+          result = parse_multipart_without_rewind(env)
+
+          begin
+            env['rack.input'].rewind if env['rack.input'].respond_to?(:rewind)
+          rescue Errno::ESPIPE
+            # Handles exceptions raised by input streams that cannot be rewound
+            # such as when using plain CGI under Apache
+          end
+
+          result
+        end
+
+        alias_method_chain :parse_multipart, :rewind
+      end
+    end
+  end
+end
diff --git a/actionpack/lib/action_controller/rewindable_input.rb b/actionpack/lib/action_controller/rewindable_input.rb
index 296d8aed22..058453ea68 100644
--- a/actionpack/lib/action_controller/rewindable_input.rb
+++ b/actionpack/lib/action_controller/rewindable_input.rb
@@ -15,15 +15,19 @@ module ActionController
         @io.rewind
       end
 
+      def string
+        @string
+      end
+
       def method_missing(method, *args, &block)
         @io.send(method, *args, &block)
       end
 
       private
         def read_original_io
-          unless @str
-            @str = @io.read
-            @io = StringIO.new(@str)
+          unless @string
+            @string = @io.read
+            @io = StringIO.new(@string)
           end
         end
     end