improve instance variable hiding

git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/base/trunk@29779 72102866-910b-0410-8b05-ffd578937521

ChangeLog

@@ -1,3 +1,15 @@
+2010-02-26 Richard Frith-Macdonald <rfm@gnu.org>
+
+	* Source/NSOperation.m:
+	* Source/GSInternal.h:
+	* Source/NSConnection.m:
+	* Headers/Foundation/NSConnection.h:
+	* Headers/Foundation/NSOperation.h:
+	* Headers/Additions/GNUstepBase/GSVersionMacros.h:
+	Rework hiding of instance variables for big classes (lots of ivars)
+	where we expect the class lifetime to be long enough that it makes
+	sense to hod the ivars in a private subclass.
+
 2010-02-26 Richard Frith-Macdonald <rfm@gnu.org>
 
 	* Source/NSNetServices.m:

Headers/Additions/GNUstepBase/GSVersionMacros.h

@@ -200,7 +200,16 @@
 #ifndef __has_feature
 #define __has_feature(x) 0
 #endif
-#define	GS_EXPOSE(X)	\
-((!__has_feature(objc_nonfragile_abi) && !__has_feature(objc_nonfragile_abi2)) || defined(EXPOSE_##X##_IVARS))
+
+#define	GS_NONFRAGILE	\
+(__has_feature(objc_nonfragile_abi) || __has_feature(objc_nonfragile_abi2))
+
+#define	GS_EXPOSE(X)	(!GS_NONFRAGILE || defined(EXPOSE_##X##_IVARS))
+
+#if	GS_NONFRAGILE
+#  define	GS_INTERNAL(X)	@public GS_##X##_IVARS
+#else
+#  define	GS_INTERNAL(X)	@private id _internal;
+#endif
 
 #endif /* __GNUSTEP_GSVERSIONMACROS_H_INCLUDED_ */

Headers/Foundation/NSConnection.h

@@ -94,10 +94,7 @@ GS_EXPORT NSString* const NSConnectionProxyCount;	/* Objects received */
  */
 @interface NSConnection : NSObject
 {
-#if	GS_EXPOSE(NSConnection)
-@private
-  id	_internal;
-#endif
+GS_INTERNAL(NSConnection)
 }
 
 + (NSArray*) allConnections;

Headers/Foundation/NSOperation.h

@@ -49,10 +49,7 @@ typedef NSInteger NSOperationQueuePriority;
 
 @interface NSOperation : NSObject
 {
-#if	GS_EXPOSE(NSOperation)
-@private
-  id	_internal;
-#endif
+GS_INTERNAL(NSOperation)
 }
 
 /** Adds a dependency to the receiver.<br />

Source/GSInternal.h

@@ -27,49 +27,43 @@
  * their code when the class implementation is changed in new versions of the
  * library.
  *
- * The public class MUST contain an instance variable 'id _internal;' to be
- * used as a pointer to a private class containing the ivars.
+ * The public class MUST contain a use of the GS_INTERNAL() macro with the
+ * class name as it's argument.
+ *
+ * Before including the header file containing the public class declaration,
+ * you must define GS_X_IVARS (where X is the class name) to be the
+ * list of actual instance variable declarations for the class.
  *
  * Before including this file, you must define 'GSInternal' to be the name
  * of your public class with * 'Internal' appended.
  * eg. if your class is called 'MyClass' then use the following define:
  * #define GSInternal MyClassInternal
  *
- * After including this file you can use the GS_BEGIN_INTERNAL() and
- * GS_END_INTERNAL() macros to bracket the declaration of the instance
- * variables.
+ * After including this file you can use the GS_PRIVATE_INTERNAL() macro
+ * to declare the private subclass used to hold real instance variables.
+ * The argument to this macro is the public class name (the GS_X_IVARS
+ * list must also be defined).
  *
  * You use GS_CREATE_INTERNAL() in your intialiser to create the object
  * holding the internal instance variables, and GS_DESTROY_INTERNAL() to
- * get rid of that object (only do this if '_internal' is not nil) in
- * your -dealloc method.
+ * get rid of that object  in your -dealloc method.
  *
  * Instance variables are referenced using the 'internal->ivar' suntax or
  * the GSIV(classname,object,ivar) macro.
  *
- * ARGH FIXME ... the following idea doesn't work ... need to rethink/rwrite.
- *
- * If built with CLANG, with support for non-fragile instance variables,
- * rather than GCC, the compiler/runtime can simply declare instance variables
- * within the implementation file so that they are not part of the public ABI,
- * in which case the macros here mostly reduce to nothing and the generated
- * code can be much more efficient.
  */
-#if	1 || !__has_feature(objc_nonfragile_abi)
+#if	!GS_NON_FRAGILE
 
-/* Code for when we don't have non-fragine instance variables
+/* Code for when we don't have non-fragile instance variables
  */
 
 /* Start declaration of internal ivars.
  */
-#define	GS_BEGIN_INTERNAL(name) \
+#define	GS_PRIVATE_INTERNAL(name) \
 @interface	name ## Internal : NSObject \
 { \
-  @public
-
-/* Finish declaration of internal ivars.
- */
-#define	GS_END_INTERNAL(name) \
+@public \
+GS_##name##_IVARS \
 } \
 @end \
 @implementation	name ## Internal \
@@ -80,29 +74,23 @@
 #define	GS_CREATE_INTERNAL(name) \
 _internal = [name ## Internal new];
 
-/* Create holder for internal ivars.
+/* Destroy holder for internal ivars.
  */
 #define	GS_DESTROY_INTERNAL(name) \
-DESTROY(_internal);
+if (_internal != 0) DESTROY(_internal);
 
 #undef	internal
 #define	internal	((GSInternal*)_internal)
 #undef	GSIVar
 #define	GSIVar(X,Y)	(((GSInternal*)(X->_internal))->Y)
 
-#else	/* !__has_feature(objc_nonfragile_abi) */
+#else	/* GS_NON_FRAGILE */
 
 /* We have support for non-fragile ivars
  */
 
-#define	GS_BEGIN_INTERNAL(name) @interface name () {
+#define	GS_PRIVATE_INTERNAL(name) 
 
-/* Finish declaration of internal ivars.
- */
-#define	GS_END_INTERNAL(name) } @end
-
-/* Create holder for internal ivars (nothing to do).
- */
 #define	GS_CREATE_INTERNAL(name)
 
 #define	GS_DESTROY_INTERNAL(name)
@@ -114,6 +102,6 @@ DESTROY(_internal);
 #undef	GSIVar
 #define	GSIVar(X,Y)	((X)->Y)
 
-#endif	/* !__has_feature(objc_nonfragile_abi) */
+#endif	/* GS_NON_FRAGILE */
 
 

Source/NSConnection.m

@@ -31,7 +31,41 @@
 
 #import "common.h"
 
-#define	EXPOSE_NSConnection_IVARS	1
+#define	GS_NSConnection_IVARS \
+  BOOL			_isValid; \
+  BOOL			_independentQueueing; \
+  BOOL			_authenticateIn; \
+  BOOL			_authenticateOut; \
+  BOOL			_multipleThreads; \
+  BOOL			_shuttingDown; \
+  BOOL			_useKeepalive; \
+  BOOL			_keepaliveWait; \
+  NSPort		*_receivePort; \
+  NSPort		*_sendPort; \
+  unsigned		_requestDepth; \
+  unsigned		_messageCount; \
+  unsigned		_reqOutCount; \
+  unsigned		_reqInCount; \
+  unsigned		_repOutCount; \
+  unsigned		_repInCount; \
+  GSIMapTable		_localObjects; \
+  GSIMapTable		_localTargets; \
+  GSIMapTable		_remoteProxies; \
+  GSIMapTable		_replyMap; \
+  NSTimeInterval	_replyTimeout; \
+  NSTimeInterval	_requestTimeout; \
+  NSMutableArray	*_requestModes; \
+  NSMutableArray	*_runLoops; \
+  NSMutableArray	*_requestQueue; \
+  id			_delegate; \
+  NSRecursiveLock	*_refGate; \
+  NSMutableArray	*_cachedDecoders; \
+  NSMutableArray	*_cachedEncoders; \
+  NSString		*_remoteName; \
+  NSString		*_registeredName; \
+  NSPortNameServer	*_nameServer; \
+  int			_lastKeepalive;
+
 #define	EXPOSE_NSDistantObject_IVARS	1
 
 #ifdef HAVE_ALLOCA_H
@@ -236,42 +270,7 @@ stringFromMsgType(int type)
 
 #define	GSInternal	NSConnectionInternal
 #include	"GSInternal.h"
-GS_BEGIN_INTERNAL(NSConnection)
-  BOOL			_isValid;
-  BOOL			_independentQueueing;
-  BOOL			_authenticateIn;
-  BOOL			_authenticateOut;
-  BOOL			_multipleThreads;
-  BOOL			_shuttingDown;
-  BOOL			_useKeepalive;
-  BOOL			_keepaliveWait;
-  NSPort		*_receivePort;
-  NSPort		*_sendPort;
-  unsigned		_requestDepth;
-  unsigned		_messageCount;
-  unsigned		_reqOutCount;
-  unsigned		_reqInCount;
-  unsigned		_repOutCount;
-  unsigned		_repInCount;
-  GSIMapTable		_localObjects;
-  GSIMapTable		_localTargets;
-  GSIMapTable		_remoteProxies;
-  GSIMapTable		_replyMap;
-  NSTimeInterval	_replyTimeout;
-  NSTimeInterval	_requestTimeout;
-  NSMutableArray	*_requestModes;
-  NSMutableArray	*_runLoops;
-  NSMutableArray	*_requestQueue;
-  id			_delegate;
-  NSRecursiveLock	*_refGate;
-  NSMutableArray	*_cachedDecoders;
-  NSMutableArray	*_cachedEncoders;
-  NSString		*_remoteName;
-  NSString		*_registeredName;
-  NSPortNameServer	*_nameServer;
-  int			_lastKeepalive;
-GS_END_INTERNAL(NSConnection)
-
+GS_PRIVATE_INTERNAL(NSConnection)
 
 #define	IisValid		(internal->_isValid)
 #define	IindependentQueueing	(internal->_independentQueueing)

Source/NSOperation.m

@@ -27,8 +27,30 @@
    */ 
 
 #import "common.h"
-#define	EXPOSE_NSOperation_IVARS	1
-#define	EXPOSE_NSOperationQueue_IVARS	1
+
+#define	GS_NSOperation_IVARS \
+  NSRecursiveLock *lock; \
+  NSConditionLock *cond; \
+  NSOperationQueuePriority priority; \
+  double threadPriority; \
+  BOOL cancelled; \
+  BOOL concurrent; \
+  BOOL executing; \
+  BOOL finished; \
+  BOOL ready; \
+  NSMutableArray *dependencies;
+
+#define	GS_NSOperationQueue_IVARS \
+  NSRecursiveLock	*lock; \
+  NSConditionLock	*cond; \
+  NSMutableArray	*operations; \
+  NSMutableArray	*waiting; \
+  NSString		*name; \
+  BOOL			suspended; \
+  NSInteger		threads; \
+  NSInteger		idle; \
+  NSInteger		count;
+
 #import "Foundation/NSOperation.h"
 #import "Foundation/NSArray.h"
 #import "Foundation/NSAutoreleasePool.h"
@@ -42,18 +64,7 @@
 
 #define	GSInternal	NSOperationInternal
 #include	"GSInternal.h"
-GS_BEGIN_INTERNAL(NSOperation)
-  NSRecursiveLock *lock;
-  NSConditionLock *cond;
-  NSOperationQueuePriority priority;
-  double threadPriority;
-  BOOL cancelled;
-  BOOL concurrent;
-  BOOL executing;
-  BOOL finished;
-  BOOL ready;
-  NSMutableArray *dependencies;
-GS_END_INTERNAL(NSOperation)
+GS_PRIVATE_INTERNAL(NSOperation)
 
 static NSArray	*empty = nil;
 
@@ -459,17 +470,7 @@ static NSArray	*empty = nil;
 #undef	GSInternal
 #define	GSInternal	NSOperationQueueInternal
 #include	"GSInternal.h"
-GS_BEGIN_INTERNAL(NSOperationQueue)
-  NSRecursiveLock	*lock;
-  NSConditionLock	*cond;
-  NSMutableArray	*operations;
-  NSMutableArray	*waiting;
-  NSString		*name;
-  BOOL			suspended;
-  NSInteger		threads;	// number of threads allocated
-  NSInteger		idle;		// threads waiting for an op to do
-  NSInteger		count;		// max executing operations
-GS_END_INTERNAL(NSOperationQueue)
+GS_PRIVATE_INTERNAL(NSOperationQueue)
 
 
 @interface	NSOperationQueue (Private)