- File.expand_path("/....") on windows platform returns "C:/...." which

is expected but not in our monkeypatching to work around other bugs.

  This should resolve logstash's known windows 'file input' problems and
  whatnot. I've tested this on a Windows Server 2012 EC2 instance
  provided by the Alex Corley at Zenoss <3

  Test config showed file inputs working. I was able to watch
  "C:\test.log" and edit the file with notepad, adding lines, and
  logstash would see new events show up when I saved.

lib/logstash/JRUBY-6970.rb

@@ -31,6 +31,7 @@ class File
     alias_method :expand_path_JRUBY_6970, :expand_path
 
     def expand_path(path, dir=nil)
+      #p :expand_path => [path, dir]
       if path =~ /(jar:)?file:\/.*\.jar!/
         #p :expand_path_path => [path, dir]
         jar, resource = path.split("!", 2)
@@ -39,7 +40,17 @@ class File
           # Nothing after the "!", nothing special to handle.
           return expand_path_JRUBY_6970(path, dir)
         else
-          return "#{jar}!#{expand_path_JRUBY_6970(resource, dir)}"
+          resource = expand_path_JRUBY_6970(resource, dir)
+          # TODO(sissel): use LogStash::Util::UNAME
+          if RbConfig::CONFIG["host_os"] == "mswin32"
+            # 'expand_path' on "/" will return "C:/" on windows.
+            # So like.. we don't want that because technically this
+            # is the root of the jar, not of a disk.
+            puts :expand_path => [path, "#{jar}!#{resource.gsub(/^[A-Z]:/, "")}"]
+            return "#{jar}!#{resource.gsub(/^[A-Z]:/, "")}"
+          else
+            return "#{jar}!#{resource}"
+          end
         end
       elsif dir =~ /(jar:)?file:\/.*\.jar!/
         jar, dir = dir.split("!", 2)