IPC::ChannelMojo: Introduce IPC::MojoBootstrap for Windows

ipc/mojo/ipc_mojo_bootstrap.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 "ipc/mojo/ipc_mojo_bootstrap.h"
+
+#include "base/logging.h"
+#include "base/process/process_handle.h"
+#include "ipc/ipc_message_utils.h"
+#include "ipc/ipc_platform_file.h"
+#include "mojo/embedder/platform_channel_pair.h"
+
+namespace IPC {
+
+namespace {
+
+// MojoBootstrap for the server process. You should create the instance
+// using MojoBootstrap::Create()

[viettrungluu, 2014/09/15 22:37:28]

nit: Needs a period at the end.

[Hajime Morrita, 2014/09/15 23:51:33]

Done.

+class IPC_MOJO_EXPORT MojoServerBootstrap : public MojoBootstrap {
+ public:
+  MojoServerBootstrap();
+
+  virtual void OnClientLaunched(base::ProcessHandle process) OVERRIDE;
+
+ private:
+  void SendClientPipe();
+  void SendClientPipeIfReady();
+
+  // Listener implementations
+  virtual bool OnMessageReceived(const Message& message) OVERRIDE;
+  virtual void OnChannelConnected(int32 peer_pid) OVERRIDE;
+
+  mojo::embedder::ScopedPlatformHandle server_pipe_;
+  base::ProcessHandle client_process_;
+  bool connected_;
+
+  DISALLOW_COPY_AND_ASSIGN(MojoServerBootstrap);
+};
+
+// MojoBootstrap for client processes. You should create the instance
+// using MojoBootstrap::Create()

[viettrungluu, 2014/09/15 22:37:27]

"

[Hajime Morrita, 2014/09/15 23:51:33]

Done.

+class IPC_MOJO_EXPORT MojoClientBootstrap : public MojoBootstrap {
+ public:
+  MojoClientBootstrap();
+
+  virtual void OnClientLaunched(base::ProcessHandle process) OVERRIDE;
+
+ private:
+  // Listener implementations
+  virtual bool OnMessageReceived(const Message& message) OVERRIDE;
+  virtual void OnChannelConnected(int32 peer_pid) OVERRIDE;
+
+  DISALLOW_COPY_AND_ASSIGN(MojoClientBootstrap);
+};
+
+} // namespace
+
+// MojoBootstrap
+
+// static
+scoped_ptr<MojoBootstrap> MojoBootstrap::Create(ChannelHandle handle,
+                                                Channel::Mode mode,
+                                                Delegate* delegate) {
+  CHECK(mode == Channel::MODE_CLIENT || mode == Channel::MODE_SERVER);
+  scoped_ptr<MojoBootstrap> self =
+      mode == Channel::MODE_CLIENT
+          ? scoped_ptr<MojoBootstrap>(new MojoClientBootstrap())
+          : scoped_ptr<MojoBootstrap>(new MojoServerBootstrap());
+  scoped_ptr<Channel> bootstrap_channel =
+      Channel::Create(handle, mode, self.get());
+  self->Init(bootstrap_channel.Pass(), delegate);
+  return self.Pass();
+}
+
+MojoBootstrap::MojoBootstrap() : delegate_(NULL), state_(STATE_INITIALIZED) {
+}
+
+MojoBootstrap::~MojoBootstrap() {
+}
+
+void MojoBootstrap::Init(scoped_ptr<Channel> channel, Delegate* delegate) {
+  channel_ = channel.Pass();
+  delegate_ = delegate;
+}
+
+bool MojoBootstrap::Connect() {
+  return channel_->Connect();
+}
+
+void MojoBootstrap::OnBadMessageReceived(const Message& message) {
+  delegate_->OnBootstrapError();
+}
+
+void MojoBootstrap::OnChannelError() {
+  if (state_ == STATE_READY)
+    return;
+  DLOG(WARNING) << "Detected error on Mojo bootstrap channel.";
+  delegate()->OnBootstrapError();
+}
+
+bool MojoBootstrap::Send(Message* message) {
+  return channel_->Send(message);
+}
+
+#if defined(OS_POSIX) && !defined(OS_NACL)
+int MojoBootstrap::GetClientFileDescriptor() const {
+  return channel_->GetClientFileDescriptor();
+}
+
+int MojoBootstrap::TakeClientFileDescriptor() {
+  return channel_->TakeClientFileDescriptor();
+}
+#endif  // defined(OS_POSIX) && !defined(OS_NACL)
+
+// MojoServerBootstrap
+
+MojoServerBootstrap::MojoServerBootstrap()

[viettrungluu, 2014/09/15 22:37:28]

Apparently, it's legal to define stuff that's declared in an anonymous namespace
without putting the definition (explicitly) in the anonymous namespace. (It
makes sense now that I think about it.)

But it's a bit weird, so you should probably put the definitions inside the
"namespace { ... }". (Maybe just move the MojoServerBootstrap methods up to
immediately follow the class declaration, and ditto for MojoClientBootstrap.)

[Hajime Morrita, 2014/09/15 23:51:33]

Ouch. This is indeed weird. Surprised that the compiler didn't complain :-(
Fixed.

+    : client_process_(base::kNullProcessHandle), connected_(false) {
+}
+
+void MojoServerBootstrap::SendClientPipe() {
+  DCHECK_EQ(state(), STATE_INITIALIZED);
+  DCHECK_NE(client_process_, base::kNullProcessHandle);
+  DCHECK(connected_);
+
+  mojo::embedder::PlatformChannelPair channel_pair;
+  server_pipe_ = channel_pair.PassServerHandle();
+  PlatformFileForTransit client_pipe = GetFileHandleForProcess(
+      channel_pair.PassClientHandle().release().ToPlaformFile(),
+      client_process_,
+      true);
+  CHECK(client_pipe != IPC::InvalidPlatformFileForTransit());
+  scoped_ptr<Message> message(new Message());
+  ParamTraits<PlatformFileForTransit>::Write(message.get(), client_pipe);
+  Send(message.release());
+
+  set_state(STATE_WAITING_ACK);
+}
+
+void MojoServerBootstrap::SendClientPipeIfReady() {
+  // Is the client launched?
+  if (client_process_ == base::kNullProcessHandle)
+    return;
+  // Has the bootstrap channel been made?
+  if (!connected_)
+    return;
+
+  SendClientPipe();
+}
+
+void MojoServerBootstrap::OnClientLaunched(base::ProcessHandle process) {
+  DCHECK_EQ(state(), STATE_INITIALIZED);
+  DCHECK_NE(process, base::kNullProcessHandle);
+  client_process_ = process;
+  SendClientPipeIfReady();
+}
+
+void MojoServerBootstrap::OnChannelConnected(int32 peer_pid) {
+  DCHECK(state() == STATE_INITIALIZED);
+  connected_ = true;
+  SendClientPipeIfReady();
+}
+
+bool MojoServerBootstrap::OnMessageReceived(const Message&) {
+  DCHECK(state() == STATE_WAITING_ACK);
+  set_state(STATE_READY);
+
+  delegate()->OnPipeAvailable(
+      mojo::embedder::ScopedPlatformHandle(server_pipe_.release()));
+
+  return true;
+}
+
+// MojoClientBootstrap
+
+MojoClientBootstrap::MojoClientBootstrap() {
+}
+
+bool MojoClientBootstrap::OnMessageReceived(const Message& message) {
+  PlatformFileForTransit pipe;
+  PickleIterator iter(message);
+  if (!ParamTraits<PlatformFileForTransit>::Read(&message, &iter, &pipe)) {
+    DLOG(WARNING) << "Failed to read a file handle from bootstrap channel.";
+    message.set_dispatch_error();
+    return false;
+  }
+
+  // Sends ACK back.
+  Send(new Message());
+  set_state(STATE_READY);
+  delegate()->OnPipeAvailable(
+      mojo::embedder::ScopedPlatformHandle(mojo::embedder::PlatformHandle(
+          PlatformFileForTransitToPlatformFile(pipe))));
+
+  return true;
+}
+
+void MojoClientBootstrap::OnClientLaunched(base::ProcessHandle process) {
+  // This notification should happen only on server processes.
+  NOTREACHED();
+}
+
+void MojoClientBootstrap::OnChannelConnected(int32 peer_pid) {
+}
+
+}  // namespace IPC