Laurent Sansonetti
lsans****@apple*****
Thu Sep 28 01:59:08 JST 2006
Hi all,
Some news regarding the recent work in the 'apple-unstable' branch!
- Informal protocols are now handled in the XML files. At build time
we describe them (via the gen_bridge_metadata script) and at runtime
we build a hash table that maps selector to the method type (encoding)
equivalent. DummyProtocolHandler has been removed.
- The XML files can contain 'exceptions'. Exceptions are written in a
separate XML file and the gen_bridge_metadata script will merge them
to the final XML file. These exceptions describe pointer-like
arguments, and also methods that should be ignored by the bridge (that
we can't handle properly). The exceptions files are not yet committed
to the SVN repository. Some examples here [1].
- libffi closures are now used in OverrideMixin as IMP method
handlers, and in the closure code we directly call the embedded Ruby
object. This is great because 1) we don't use NSInvocation anymore and
2) it now works with floating point arguments (this fixes bug #1535223
in SF.net). So faster and more reliable.
- A bug was found in the memory retention code. Some classes
(NSDictionary for example) always return the same object in [- alloc],
and they return the real new ObjC object in the [-init] method. Ruby
was keeping a Ruby'fied version of the singleton ObjC object and
releasing it after garbage collection, which was crashing the next
call to [NSDictionary alloc]. RubyCocoa was fixed to not mark objects
from [-alloc] and [-allocWithZone:] to be released upon garbage
collection. It appears that this problem is only on recent Mac OS X
builds (10.5), so I didn't port the fix to the stable branch (yet).
Laurent
[1]:
Calling an ignored method:
irb(main):001:0> x = OSX::NSData.alloc.init
=> #<OSX::NSConcreteData:0x2307a class='NSConcreteData' id=0x3de8c0>
irb(main):002:0> OSX::NSData.dataWithBytesNoCopy_length(nil)
RuntimeError: Method 'dataWithBytesNoCopy:length:' is not supported
(suggested alternative: 'Call dataWithBytes:length:.')
from /Volumes/Data/src/svn-rubycocoa-apple/framework/build/
Default/RubyCocoa.framework/Versions/A/Resources/ruby/osx/objc/
oc_wrapper.rb:17:in `ocm_send'
from /Volumes/Data/src/svn-rubycocoa-apple/framework/build/
Default/RubyCocoa.framework/Versions/A/Resources/ruby/osx/objc/
oc_wrapper.rb:17:in `method_missing'
from (irb):2
Calling a method with an 'in' C-like array delimited by another
argument. Note the warning that is raised by the first instruction,
the 'length' argument is no longer needed, as we can determine it from
the 'bytes' argument, thanks to the metadata. We also get the data
after that (using the same way as before, but with an 'out' argument).
irb(main):003:0> x = OSX::NSData.alloc.initWithBytes_length('foobar', 6)
/Volumes/Data/src/svn-rubycocoa-apple/framework/build/Default/
RubyCocoa.framework/Versions/A/Resources/ruby/osx/objc/oc_wrapper.rb:
17: warning: NSConcreteData#initWithBytes:length: argument #1 is no
longer necessary (will be ignored)
=> #<OSX::NSConcreteData:0x2fafa class='NSConcreteData' id=0x329b40>
irb(main):004:0> x = OSX::NSData.alloc.initWithBytes_length('foobar')
=> #<OSX::NSConcreteData:0x1cc52 class='NSConcreteData' id=0x3e7510>
irb(main):005:0> data = ' ' * 6
=> " "
irb(main):006:0> x.getBytes_length(data)
=> nil
irb(main):007:0> p data
"foobar"
Calling a method with a C-like array of 'id' variables. We can
determine from the ObjC runtime if a parameter is a pointer of 'id'.
From the metadata we can know determine if it's a C-array, so instead
of passing some kind of raw data, we can support a better way, as a
real Ruby array of objects.
irb(main):010:0> ary = OSX::NSArray.arrayWithObjects_count(['a',
OSX::NSObject.alloc.init, OSX::NSNumber.numberWithFloat(3.141592)])
=> #<OSX::NSCFArray:0x22454 class='NSCFArray' id=0x3702b0>
irb(main):011:0> ary.objectAtIndex(0)
=> #<OSX::NSCFString:0x1fa10 class='NSCFString' id=0x3701e0>
irb(main):012:0> ary.objectAtIndex(0).to_s
=> "a"
irb(main):013:0> ary.objectAtIndex(1)
=> #<OSX::NSObject:0x23714 class='NSObject' id=0x378720>
irb(main):014:0> ary.objectAtIndex(2)
=> #<OSX::NSCFNumber:0x22a12 class='NSCFNumber' id=0x3eb130>
irb(main):015:0> ary.objectAtIndex(2).floatValue
=> 3.14159202575684
Finally, we also support methods with several C-like array but
determined by the same 'length' argument. Passing 2 arrays of
different length will raise an exception though.
irb(main):020:0> keys = ['k1', 'k2']
=> ["k1", "k2"]
irb(main):021:0> dict =
OSX::NSDictionary.dictionaryWithObjects_forKeys_count(['o1','o2'], keys)
=> #<OSX::NSCFDictionary:0x231c4 class='NSCFDictionary' id=0x3d2570>
irb(main):022:0> dict.count
=> 2
irb(main):023:0> dict.objectForKey(keys.first).to_s
=> "o1"
irb(main):024:0> dict.objectForKey(keys.last).to_s
=> "o2"