Support exposing Mojo services between render frames, render threads, and their respective hosts.

content/common/mojo/service_registry_impl.h

+// 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.
+
+#ifndef CONTENT_COMMON_MOJO_SERVICE_REGISTRY_IMPL_H_
+#define CONTENT_COMMON_MOJO_SERVICE_REGISTRY_IMPL_H_
+
+#include <map>
+#include <queue>
+#include <string>
+#include <utility>
+
+#include "base/callback.h"
+#include "content/public/common/service_registry.h"
+#include "mojo/public/cpp/bindings/interface_impl.h"
+#include "mojo/public/cpp/system/core.h"
+#include "mojo/public/interfaces/interface_provider/interface_provider.mojom.h"
+
+namespace content {
+
+class ServiceRegistryImpl
+    : public ServiceRegistry,
+      public mojo::InterfaceImpl<mojo::IInterfaceProvider> {
+ public:
+  ServiceRegistryImpl();
+  explicit ServiceRegistryImpl(mojo::ScopedMessagePipeHandle handle);
+  virtual ~ServiceRegistryImpl();
+
+  // Binds to a remote ServiceProvider. This will expose added services to the
+  // remote ServiceProvider with the corresponding handle and enable
+  // GetInterface to provide access to services exposed by the remote
+  // ServiceProvider.
+  void Bind(mojo::ScopedMessagePipeHandle handle);

[darin (slow to review), 2014/06/18 00:09:28]

nit: You might call this method BindRemoteServiceProvider for clarity.

[Sam McNally, 2014/06/18 01:31:40]

Done.

+
+  // ServiceRegistry overrides.
+  virtual void AddService(
+      const std::string& service_name,
+      const base::Callback<void(mojo::ScopedMessagePipeHandle)> service_factory)
+      OVERRIDE;
+  virtual void RemoveService(const std::string& service_name) OVERRIDE;
+  virtual void GetInterface(const base::StringPiece& service_name,
+                            mojo::ScopedMessagePipeHandle handle) OVERRIDE;
+
+ private:
+  // mojo::InterfaceImpl<mojo::IInterfaceProvider> overrides.
+  virtual void GetInterface(
+      const mojo::String& name,
+      mojo::ScopedMessagePipeHandle client_handle) OVERRIDE;
+  virtual void OnConnectionError() OVERRIDE;
+
+  std::map<std::string, base::Callback<void(mojo::ScopedMessagePipeHandle)> >
+      service_factories_;
+  std::queue<std::pair<std::string, mojo::MessagePipeHandle> >
+      pending_connects_;
+  bool bound_;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_COMMON_MOJO_SERVICE_REGISTRY_IMPL_H_