libs-base/Source/GSBlocks.m

#import <Foundation/NSObject.h>

/* Declare the block copy functions ourself so that we don't depend on a
 * specific header location.
 */
void *_Block_copy(void *);
void _Block_release(void *);

@interface GSBlock : NSObject
@end

@implementation GSBlock
+ (void) load
{
  unsigned int	methodCount;
  Method	*m = NULL;
  Method	*methods = class_copyMethodList(self, &methodCount);
  id		blockClass = objc_lookUpClass("_NSBlock");
  Protocol	*nscopying = NULL;

  /* If we don't have an _NSBlock class, we don't have blocks support in the
   * runtime, so give up.
   */
  if (nil == blockClass)
    {
      return;
    }

  /* Copy all of the methods in this class onto the block-runtime-provided
   * _NSBlock
   */
  for (m = methods; NULL != *m; m++)
    {
      class_addMethod(blockClass, method_getName(*m),
	method_getImplementation(*m), method_getTypeEncoding(*m));
    }
  nscopying = objc_getProtocol("NSCopying");
  class_addProtocol(blockClass, nscopying);
}

- (id) copyWithZone: (NSZone*)aZone
{
  return _Block_copy(self);
}

- (id) copy
{
  return _Block_copy(self);
}

- (id) retain
{
  return _Block_copy(self);
}

- (void) release
{
  _Block_release(self);
}
@end