Mojo: Cancel WaitingCallbacks when their HandleWrappers are closed.

mojo/bindings/js/waiting_callback.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "mojo/bindings/js/waiting_callback.h"
 
 #include "gin/per_context_data.h"
 #include "mojo/public/cpp/environment/environment.h"
 
 namespace mojo {
 namespace js {
 
 namespace {
 
 v8::Handle<v8::String> GetHiddenPropertyName(v8::Isolate* isolate) {
   return gin::StringToSymbol(isolate, "::mojo::js::WaitingCallback");
 }
 
 }  // namespace
 
 gin::WrapperInfo WaitingCallback::kWrapperInfo = { gin::kEmbedderNativeGin };
 
 // static
 gin::Handle<WaitingCallback> WaitingCallback::Create(
     v8::Isolate* isolate,
     v8::Handle<v8::Function> callback,
-    mojo::Handle handle,
+    gin::Handle<gin::HandleWrapper> handle_wrapper,
     MojoHandleSignals signals) {
-  gin::Handle<WaitingCallback> waiting_callback =
-      gin::CreateHandle(isolate, new WaitingCallback(isolate, callback));
+  gin::Handle<WaitingCallback> waiting_callback = gin::CreateHandle(
+      isolate, new WaitingCallback(isolate, callback, handle_wrapper));
   waiting_callback->wait_id_ = Environment::GetDefaultAsyncWaiter()->AsyncWait(
-      handle.value(),
+      handle_wrapper->get().value(),
       signals,
       MOJO_DEADLINE_INDEFINITE,
       &WaitingCallback::CallOnHandleReady,
       waiting_callback.get());
   return waiting_callback;
 }
 
 void WaitingCallback::Cancel() {
   if (!wait_id_)
     return;
 
+  handle_wrapper_->RemoveCloseObserver(this);
+  handle_wrapper_ = NULL;
   Environment::GetDefaultAsyncWaiter()->CancelWait(wait_id_);
   wait_id_ = 0;
 }
 
 WaitingCallback::WaitingCallback(v8::Isolate* isolate,
-                                 v8::Handle<v8::Function> callback)
-      : wait_id_() {
+                                 v8::Handle<v8::Function> callback,
+                                 gin::Handle<gin::HandleWrapper> handle_wrapper)
+    : wait_id_(0), handle_wrapper_(handle_wrapper.get()) {
+  handle_wrapper_->AddCloseObserver(this);
   v8::Handle<v8::Context> context = isolate->GetCurrentContext();
   runner_ = gin::PerContextData::From(context)->runner()->GetWeakPtr();
   GetWrapper(isolate)->SetHiddenValue(GetHiddenPropertyName(isolate), callback);
 }
 
 WaitingCallback::~WaitingCallback() {
   Cancel();
 }
 
 // static
 void WaitingCallback::CallOnHandleReady(void* closure, MojoResult result) {
   static_cast<WaitingCallback*>(closure)->OnHandleReady(result);
 }
 
 void WaitingCallback::OnHandleReady(MojoResult result) {
   wait_id_ = 0;
+  handle_wrapper_->RemoveCloseObserver(this);
+  handle_wrapper_ = NULL;
 
   if (!runner_)
     return;
 
   gin::Runner::Scope scope(runner_.get());
   v8::Isolate* isolate = runner_->GetContextHolder()->isolate();
 
   v8::Handle<v8::Value> hidden_value =
       GetWrapper(isolate)->GetHiddenValue(GetHiddenPropertyName(isolate));
   v8::Handle<v8::Function> callback;
   CHECK(gin::ConvertFromV8(isolate, hidden_value, &callback));
 
   v8::Handle<v8::Value> args[] = { gin::ConvertToV8(isolate, result) };
   runner_->Call(callback, runner_->global(), 1, args);
 }
 
+void WaitingCallback::OnWillCloseHandle() {
+  Environment::GetDefaultAsyncWaiter()->CancelWait(wait_id_);
+  OnHandleReady(MOJO_RESULT_INVALID_ARGUMENT);
+}
+
 }  // namespace js
 }  // namespace mojo