In libobjc/: 2010-10-16 Nicola Pero <nicola.pero@meta-innovation.com>

In libobjc/:
2010-10-16  Nicola Pero  <nicola.pero@meta-innovation.com>

        * objc/runtime.h: Updated comments.
        (class_addMethod): New.
        (class_addIvar): New.
        (class_replaceMethod): New.
        (objc_allocateClassPair): New.
        (objc_registerClassPair): New.
        (objc_disposeClassPair): New.
        * class.c (objc_allocateClassPair): New.
        (objc_registerClassPair): New.
        (objc_disposeClassPair): New.
        (class_getSuperclass): Return Nil if a class is in construction.
        * init.c (__objc_exec_class): Call __objc_init_class.
        (__objc_init_class): New.
        * ivars.c (class_copyIvarList): Return NULL if class is in
        construction.  Do not lock the runtime mutex.
        (class_getInstanceVariable): Return NULL if class is in
        construction.  Do not lock the runtime mutex.
        (class_addIvar): New.
        * sendmsg.c (class_addMethod): New.
        (class_replaceMethod): New.
        * objc-private/module-abi-8.h (__CLS_SETNOTINFO): New.
        (_CLS_IN_CONSTRUCTION): New.
        (CLS_IS_IN_CONSTRUCTION): New.
        (CLS_SET_IN_CONSTRUCTION): New.
        (CLS_SET_NOT_IN_CONSTRUCTION): New.
        * objc-private/runtime.h (__objc_init_class): New.

From-SVN: r165563

1 files changed, 198 insertions, 0 deletions

diff --git a/libobjc/class.c b/libobjc/class.c
index 71483457e25..ade5a71f453 100644
--- a/libobjc/class.c
+++ b/libobjc/class.c
@@ -570,6 +570,199 @@ objc_getClassList (Class *returnValue, int maxNumberOfClassesToReturn)
   return count;
 }
 
+Class
+objc_allocateClassPair (Class super_class, const char *class_name, size_t extraBytes)
+{
+  Class new_class;
+  Class new_meta_class;
+
+  if (class_name == NULL)
+    return Nil;
+
+  if (objc_getClass (class_name))
+    return Nil;
+
+  if (super_class)
+    {
+      /* If you want to build a hierarchy of classes, you need to
+	 build and register them one at a time.  The risk is that you
+	 are able to cause confusion by registering a subclass before
+	 the superclass or similar.  */
+      if (CLS_IS_IN_CONSTRUCTION (super_class))
+	return Nil;
+    }
+
+  /* Technically, we should create the metaclass first, then use
+     class_createInstance() to create the class.  That complication
+     would be relevant if we had class variables, but we don't, so we
+     just ignore it and create everything directly and assume all
+     classes have the same size.  */
+  new_class = objc_calloc (1, sizeof (struct objc_class) + extraBytes);
+  new_meta_class = objc_calloc (1, sizeof (struct objc_class) + extraBytes);
+
+  /* We create an unresolved class, similar to one generated by the
+     compiler.  It will be resolved later when we register it.
+
+     Note how the metaclass details are not that important; when the
+     class is resolved, the ones that matter will be fixed up.  */
+  new_class->class_pointer = new_meta_class;
+  new_meta_class->class_pointer = 0;
+
+  if (super_class)
+    {
+      /* Force the name of the superclass in place of the link to the
+	 actual superclass, which will be put there when the class is
+	 resolved.  */
+      const char *super_class_name = class_getName (super_class);
+      new_class->super_class = (void *)super_class_name;
+      new_meta_class->super_class = (void *)super_class_name;
+    }
+  else
+    {
+      new_class->super_class = (void *)0;
+      new_meta_class->super_class = (void *)0;
+    }
+
+  new_class->name = objc_malloc (strlen (class_name) + 1);
+  strcpy ((char*)new_class->name, class_name);
+  new_meta_class->name = new_class->name;
+
+  new_class->version = 0;
+  new_meta_class->version = 0;
+
+  new_class->info = _CLS_CLASS | _CLS_IN_CONSTRUCTION;
+  new_meta_class->info = _CLS_META | _CLS_IN_CONSTRUCTION;
+
+  if (super_class)
+    new_class->instance_size = super_class->instance_size;
+  else
+    new_class->instance_size = 0;
+  new_meta_class->instance_size = sizeof (struct objc_class);
+
+  return new_class;
+}
+
+void
+objc_registerClassPair (Class class_)
+{
+  if (class_ == Nil)
+    return;
+
+  if ((! CLS_ISCLASS (class_)) || (! CLS_IS_IN_CONSTRUCTION (class_)))
+    return;
+
+  if ((! CLS_ISMETA (class_->class_pointer)) || (! CLS_IS_IN_CONSTRUCTION (class_->class_pointer)))
+    return;
+
+  objc_mutex_lock (__objc_runtime_mutex);
+
+  if (objc_getClass (class_->name))
+    {
+      objc_mutex_unlock (__objc_runtime_mutex);
+      return;
+    }
+
+  CLS_SET_NOT_IN_CONSTRUCTION (class_);
+  CLS_SET_NOT_IN_CONSTRUCTION (class_->class_pointer);
+
+  __objc_init_class (class_);
+
+  /* Resolve class links immediately.  No point in waiting.  */
+  __objc_resolve_class_links ();
+
+  objc_mutex_unlock (__objc_runtime_mutex);
+}
+
+void
+objc_disposeClassPair (Class class_)
+{
+  if (class_ == Nil)
+    return;
+
+  if ((! CLS_ISCLASS (class_)) || (! CLS_IS_IN_CONSTRUCTION (class_)))
+    return;
+
+  if ((! CLS_ISMETA (class_->class_pointer)) || (! CLS_IS_IN_CONSTRUCTION (class_->class_pointer)))
+    return;
+
+  /* Undo any class_addIvar().  */
+  if (class_->ivars)
+    {
+      int i;
+      for (i = 0; i < class_->ivars->ivar_count; i++)
+	{
+	  struct objc_ivar *ivar = &(class_->ivars->ivar_list[i]);
+
+	  objc_free ((char *)ivar->ivar_name);
+	  objc_free ((char *)ivar->ivar_type);
+	}
+      
+      objc_free (class_->ivars);
+    }
+
+  /* Undo any class_addMethod().  */
+  if (class_->methods)
+    {
+      struct objc_method_list *list = class_->methods;
+      while (list)
+	{
+	  int i;
+	  struct objc_method_list *next = list->method_next;
+
+	  for (i = 0; i < list->method_count; i++)
+	    {
+	      struct objc_method *method = &(list->method_list[i]);
+
+	      objc_free ((char *)method->method_name);
+	      objc_free ((char *)method->method_types);
+	    }
+
+	  objc_free (list);
+	  list = next;
+	}
+    }
+
+  /* Undo any class_addProtocol().  */
+  if (class_->protocols)
+    {
+      struct objc_protocol_list *list = class_->protocols;
+      while (list)
+	{
+	  struct objc_protocol_list *next = list->next;
+
+	  objc_free (list);
+	  list = next;
+	}
+    }
+  
+  /* Undo any class_addMethod() on the meta-class.  */
+  if (class_->class_pointer->methods)
+    {
+      struct objc_method_list *list = class_->class_pointer->methods;
+      while (list)
+	{
+	  int i;
+	  struct objc_method_list *next = list->method_next;
+
+	  for (i = 0; i < list->method_count; i++)
+	    {
+	      struct objc_method *method = &(list->method_list[i]);
+
+	      objc_free ((char *)method->method_name);
+	      objc_free ((char *)method->method_types);
+	    }
+
+	  objc_free (list);
+	  list = next;
+	}
+    }
+
+  /* Undo objc_allocateClassPair().  */
+  objc_free ((char *)(class_->name));
+  objc_free (class_->class_pointer);
+  objc_free (class_);
+}
+
 /* Traditional GNU Objective-C Runtime API.  */
 /* Get the class object for the class named NAME.  If NAME does not
    identify a known class, the hook _objc_lookup_class is called.  If
@@ -807,6 +1000,11 @@ class_getSuperclass (Class class_)
   if (class_ == Nil)
     return Nil;
 
+  /* Classes that are in construction are not resolved and can not be
+     resolved!  */
+  if (CLS_IS_IN_CONSTRUCTION (class_))
+    return Nil;
+
   /* If the class is not resolved yet, super_class would point to a
      string (the name of the super class) as opposed to the actual
      super class.  In that case, we need to resolve the class links