Verify proper API use of acquire/release typed data

runtime/vm/dart_api_impl.cc

 // Copyright (c) 2013, 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.
 
 #include "include/dart_api.h"
 #include "include/dart_mirrors_api.h"
 #include "include/dart_native_api.h"
 
 #include "platform/assert.h"
 #include "vm/class_finalizer.h"
@@ skipping 29 matching lines @@
 #include "vm/version.h"
 
 namespace dart {
 
 DECLARE_FLAG(bool, print_class_table);
 DECLARE_FLAG(bool, verify_handles);
 DEFINE_FLAG(bool, check_function_fingerprints, false,
             "Check function fingerprints");
 DEFINE_FLAG(bool, trace_api, false,
             "Trace invocation of API calls (debug mode only)");
+DEFINE_FLAG(bool, verify_acquired_data, false,
+            "Verify correct API acquire/release of typed data.");
 
 ThreadLocalKey Api::api_native_key_ = OSThread::kUnsetThreadLocalKey;
 Dart_Handle Api::true_handle_ = NULL;
 Dart_Handle Api::false_handle_ = NULL;
 Dart_Handle Api::null_handle_ = NULL;
 Dart_Handle Api::empty_string_handle_ = NULL;
 
 
 const char* CanonicalFunction(const char* func) {
   if (strncmp(func, "dart::", 6) == 0) {
@@ skipping 3367 matching lines @@
     START_NO_CALLBACK_SCOPE(isolate);
     if (TypedData::IsTypedData(obj)) {
       const TypedData& data_obj = TypedData::Cast(obj);
       *data = data_obj.DataAddr(offset_in_bytes);
     } else {
       ASSERT(ExternalTypedData::IsExternalTypedData(obj));
       const ExternalTypedData& data_obj = ExternalTypedData::Cast(obj);
       *data = data_obj.DataAddr(offset_in_bytes);
     }
   }
+  if (FLAG_verify_acquired_data) {
+    // For now, we just verify that acquire/release are properly matched
+    // per object.
+    // TODO(koda): Copy internal data to/from a side buffer which is unmapped
+    // on release to catch use-after-release bugs.
+    const Object& obj = Object::Handle(isolate, Api::UnwrapHandle(object));
+    WeakTable* table = isolate->api_state()->acquired_table();
+    intptr_t current = table->GetValue(obj.raw());
+    if (current != 0) {
+      ASSERT(current == 1);
+      return Api::NewError("Data was already acquired for this object.");
+    }
+    table->SetValue(obj.raw(), 1);
+  }
   return Api::Success();
 }
 
 
 DART_EXPORT Dart_Handle Dart_TypedDataReleaseData(Dart_Handle object) {
   Isolate* isolate = Isolate::Current();
   DARTSCOPE(isolate);
   intptr_t class_id = Api::ClassId(object);
   if (!RawObject::IsExternalTypedDataClassId(class_id) &&
       !RawObject::IsTypedDataViewClassId(class_id) &&
       !RawObject::IsTypedDataClassId(class_id)) {
     RETURN_TYPE_ERROR(isolate, object, 'TypedData');
   }
   if (!RawObject::IsExternalTypedDataClassId(class_id)) {
     isolate->DecrementNoGCScopeDepth();
     END_NO_CALLBACK_SCOPE(isolate);
   }
+  if (FLAG_verify_acquired_data) {
+    const Object& obj = Object::Handle(isolate, Api::UnwrapHandle(object));
+    WeakTable* table = isolate->api_state()->acquired_table();
+    intptr_t current = table->GetValue(obj.raw());
+    if (current != 1) {
+      ASSERT(current == 0);
+      return Api::NewError("Data was not acquired for this object.");
+    }
+    // Delete entry from table.
+    table->SetValue(obj.raw(), 0);
+  }
   return Api::Success();
 }
 
 
 DART_EXPORT Dart_Handle Dart_GetDataFromByteBuffer(Dart_Handle object) {
   Isolate* isolate = Isolate::Current();
   CHECK_ISOLATE(isolate);
   intptr_t class_id = Api::ClassId(object);
   if (class_id != kByteBufferCid) {
     RETURN_TYPE_ERROR(isolate, object, 'ByteBuffer');
@@ skipping 1961 matching lines @@
 
 
 DART_EXPORT void Dart_RegisterRootServiceRequestCallback(
     const char* name,
     Dart_ServiceRequestCallback callback,
     void* user_data) {
   Service::RegisterRootEmbedderCallback(name, callback, user_data);
 }
 
 }  // namespace dart