rubycocoa-talk

[Rubycocoa-talk] writing ruby extensions with rubycocoa

[Tim B. <tim...@gm...>]

One of my favorite things about rubycocoa is how easily I can use it
to call C code from Ruby.  It's perhaps an obvious advantage, but an
underappreciated one as well.

To illustrate it, I've written a small article that shows how to wrap
Dave Thomas' jukebox example with rubycocoa.  It is online here:

http://www.rubycocoa.com/ruby-extensions-with-rubycocoa

Please take a look sometime and send me any thoughts or suggestions.

thanks!

Tim

Re: [Rubycocoa-talk] writing ruby extensions with rubycocoa

[Jonathan P. <jp...@dc...>]

On 2 Feb 2006, at 23:53, Tim Burks wrote:

> To illustrate it, I've written a small article that shows how to wrap
> Dave Thomas' jukebox example with rubycocoa.  It is online here:
>
> http://www.rubycocoa.com/ruby-extensions-with-rubycocoa
>
> Please take a look sometime and send me any thoughts or suggestions.

This looks cool.

> Memory deallocation is handled the Cocoa way rather than the Ruby =20
> way. So even though we=92ve gotten rid of all references to our =20
> jukebox object, it=92s not deleted until the Objective-C runtime =20
> cleans up. In our example, that happens when we exit irb.
Isn't it just that ruby's garbage collector hasn't run yet, and so =20
the Ruby reference to the ObjC object is still around? Try putting =20
GC.start before exiting and see if that forces the deallocation.


I've just been playing with RubyInline for simple C interfacing. I =20
wanted to register a global hotkey, which requires accessing Carbon =20
event APIs. Here's a nippet of the code:

class Controller < NSObject
   def self.shared_instance
     @instance ||=3D Controller.alloc.init
   end

   inline do |builder|
     builder.src_ext =3D "m"
     builder.prefix %q{
     #undef T_DATA
     } # required because Ruby and Quicktime both define T_DATA
     builder.include "<Carbon/Carbon.h>"
     builder.prefix %q{
         EventHotKeyRef gMyHotKeyRef;
         EventHotKeyID gMyHotKeyID;
         static OSStatus MyHotKeyHandler(EventHandlerCallRef =20
nextHandler,EventRef theEvent,void *userData)
         {
           rb_eval_string("Controller.shared_instance.hotkey_pressed");
           return noErr;
         }
     }
     builder.c_singleton %q{
       void register_key(int keycode) {
         EventTypeSpec eventType;
         eventType.eventClass=3DkEventClassKeyboard;
         eventType.eventKind=3DkEventHotKeyPressed;
         InstallApplicationEventHandler(&MyHotKeyHandler,=20
1,&eventType,NULL,NULL);
         gMyHotKeyID.signature=3D'WBCM'; // choose something here
         gMyHotKeyID.id=3D1;
         RegisterEventHotKey(keycode, cmdKey, gMyHotKeyID, =20
GetApplicationEventTarget(), 0, &gMyHotKeyRef);

       }
     }
   end

   def hotkey_pressed
     ...
   end
end

# During initialisation...
Controller.register_key

--- inline.rb	1970-01-01 01:00:00.000000000 +0100
+++ ../inline.rb	2006-02-03 09:14:59.000000000 +0000
@@ -260,6 +260,7 @@
      public
+    attr_accessor :src_ext
      def initialize(mod)
        raise ArgumentError, "Class/Module arg is required" unless =20
Module =3D=3D=3D mod
        # new (but not on some 1.8s) -> inline -> real_caller|eval
@@ -276,6 +277,7 @@
        @sig =3D {}
        @flags =3D []
        @libs =3D []
+      @src_ext =3D "c"
      end
      ##
@@ -310,7 +312,7 @@
        unless so_exists and File.mtime(rb_file) < File.mtime(so_name)
=09
-	src_name =3D "#{Inline.directory}/#{module_name}.c"
+	src_name =3D "#{Inline.directory}/#{module_name}.#{src_ext}"
	old_src_name =3D "#{src_name}.old"
	should_compare =3D File.write_with_backup(src_name) do |io|
	  io.puts