Lazy load chrome.* APIs

chrome/renderer/extensions/object_backed_native_handler.cc

+// Copyright (c) 2012 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 "chrome/renderer/extensions/object_backed_native_handler.h"
+
+#include "base/logging.h"
+#include "base/memory/linked_ptr.h"
+#include "chrome/renderer/extensions/module_system.h"
+#include "v8/include/v8.h"
+
+namespace extensions {
+
+// Data to pass to ObjectBackedNativeHandler::Router.
+struct ObjectBackedNativeHandler::RouterData {
+  RouterData(ObjectBackedNativeHandler* self, HandlerFunction function)
+    : self(self), function(function) {}
+
+  ~RouterData() {}
+
+  // The owner of the routed data.
+  ObjectBackedNativeHandler* const self;
+
+  // The function to route calls to.
+  HandlerFunction function;
+};
+
+ObjectBackedNativeHandler::ObjectBackedNativeHandler(
+    v8::Handle<v8::Context> context)
+    : v8_context_(context),
+      object_template_(v8::ObjectTemplate::New()) {
+}
+
+ObjectBackedNativeHandler::~ObjectBackedNativeHandler() {
+  Invalidate();
+}
+
+v8::Handle<v8::Object> ObjectBackedNativeHandler::NewInstance() {
+  return object_template_->NewInstance();
+}
+
+// static
+v8::Handle<v8::Value> ObjectBackedNativeHandler::Router(
+    const v8::Arguments& args) {
+  RouterData* router_data = static_cast<RouterData*>(
+      args.Data().As<v8::External>()->Value());
+  // Router can be called during context destruction. Stop.
+  if (!router_data->self->is_valid())
+    return v8::Handle<v8::Value>();
+  return router_data->function.Run(args);
+}
+
+void ObjectBackedNativeHandler::RouteFunction(
+    const std::string& name,
+    const HandlerFunction& handler_function) {
+  linked_ptr<RouterData> data(new RouterData(this, handler_function));
+  // TODO(koz): Investigate using v8's MakeWeak() function instead of holding
+  // on to these pointers here.
+  router_data_.push_back(data);
+  v8::Handle<v8::FunctionTemplate> function_template =
+      v8::FunctionTemplate::New(Router, v8::External::New(data.get()));
+  object_template_->Set(name.c_str(), function_template);
+}
+
+void ObjectBackedNativeHandler::RouteStaticFunction(
+    const std::string& name,
+    const HandlerFunc handler_func) {
+  v8::Handle<v8::FunctionTemplate> function_template =
+      v8::FunctionTemplate::New(handler_func, v8::External::New(this));
+  object_template_->Set(name.c_str(), function_template);
+}
+
+void ObjectBackedNativeHandler::Invalidate() {
+  if (!is_valid())
+    return;
+  object_template_.reset();
+  v8_context_.reset();
+  NativeHandler::Invalidate();
+}
+
+}   // extensions