Track external allocated memory for weak persistent handles.

runtime/include/dart_api.h

 /*
  * Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
  * for details. All rights reserved. Use of this source code is governed by a
  * BSD-style license that can be found in the LICENSE file.
  */
 
 #ifndef INCLUDE_DART_API_H_
 #define INCLUDE_DART_API_H_
 
 /** \mainpage Dart Embedding API Reference
@@ skipping 424 matching lines @@
 /**
  * Allocates a weak persistent handle for an object.
  *
  * This handle has the lifetime of the current isolate unless it is
  * explicitly deallocated by calling Dart_DeleteWeakPersistentHandle.
  *
  * If the object becomes unreachable the callback is invoked with the weak
  * persistent handle and the peer as arguments. This gives the native code the
  * ability to cleanup data associated with the object and to delete the weak
  * persistent handle. It is illegal to call into the VM from the callback,
- * except to delete the weak persistent handle.
+ * except to delete the weak persistent handle. If the handle is deleted before
+ * the object becomes unreachable, the callback is never invoked.
  *
  * Requires there to be a current isolate.
  *
  * \param object An object.
  * \param peer A pointer to a native object or NULL.  This value is
  *   provided to callback when it is invoked.
+ * \param external_allocation_size The number of externally allocated
+ *   bytes for peer. Used to inform the garbage collector.
  * \param callback A function pointer that will be invoked sometime
- *   after the object is garbage collected.
+ *   after the object is garbage collected, unless the handle has been deleted.
  *
  * \return Success if the weak persistent handle was
  *   created. Otherwise, returns an error.
  */
 DART_EXPORT Dart_WeakPersistentHandle Dart_NewWeakPersistentHandle(
     Dart_Handle object,
     void* peer,
+    intptr_t external_allocation_size,
     Dart_WeakPersistentHandleFinalizer callback);
 
 DART_EXPORT void Dart_DeleteWeakPersistentHandle(
     Dart_Isolate isolate,
     Dart_WeakPersistentHandle object);
 
 /**
  * Allocates a prologue weak persistent handle for an object.
  *
  * Prologue weak persistent handles are similar to weak persistent
  * handles but exhibit different behavior during garbage collections
  * that invoke the prologue and epilogue callbacks.  While weak
  * persistent handles always weakly reference their referents,
  * prologue weak persistent handles weakly reference their referents
  * only during a garbage collection that invokes the prologue and
  * epilogue callbacks.  During all other garbage collections, prologue
  * weak persistent handles strongly reference their referents.
  *
  * This handle has the lifetime of the current isolate unless it is
  * explicitly deallocated by calling Dart_DeleteWeakPersistentHandle.
  *
  * Requires there to be a current isolate.
  *
  * \param object An object.
  * \param peer A pointer to a native object or NULL.  This value is
  *   provided to callback when it is invoked.
+ * \param external_allocation_size The number of externally allocated
+ *   bytes for peer. Used to inform the garbage collector.
  * \param callback A function pointer that will be invoked sometime
- *   after the object is garbage collected.
+ *   after the object is garbage collected, unless the handle has been deleted.
  *
  * \return Success if the prologue weak persistent handle was created.
  *   Otherwise, returns an error.
  */
 DART_EXPORT Dart_WeakPersistentHandle Dart_NewPrologueWeakPersistentHandle(
     Dart_Handle object,
     void* peer,
+    intptr_t external_allocation_size,
     Dart_WeakPersistentHandleFinalizer callback);
 
 /**
  * Is this object a prologue weak persistent handle?
  *
  * Requires there to be a current isolate.
  */
 DART_EXPORT bool Dart_IsPrologueWeakPersistentHandle(
     Dart_WeakPersistentHandle object);
 
@@ skipping 350 matching lines @@
  */
 DART_EXPORT Dart_Isolate Dart_CreateIsolate(const char* script_uri,
                                             const char* main,
                                             const uint8_t* snapshot,
                                             void* callback_data,
                                             char** error);
 /* TODO(turnidge): Document behavior when there is already a current
  * isolate. */
 
 /**
- * Shuts down the current isolate. After this call, the current
- * isolate is NULL.
+ * Shuts down the current isolate. After this call, the current isolate
+ * is NULL. Invokes the shutdown callback and any callbacks of remaining
+ * weak persistent handles.
  *
  * Requires there to be a current isolate.
  */
 DART_EXPORT void Dart_ShutdownIsolate();
 /* TODO(turnidge): Document behavior when there is no current isolate. */
 
 /**
  * Returns the current isolate. Will return NULL if there is no
  * current isolate.
  */
@@ skipping 1665 matching lines @@
  * NOTE: If multiple callbacks with the same name are registered, only the
  * last callback registered will be remembered.
  */
 DART_EXPORT void Dart_RegisterRootServiceRequestCallback(
     const char* name,
     Dart_ServiceRequestCallback callback,
     void* user_data);
 
 
 #endif  /* INCLUDE_DART_API_H_ */  /* NOLINT */