arc-bridge: Add IPC message definitions

chromeos/arc/libarcbridge/arc_bridge.cc

+// Copyright 2015 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 "arc_bridge.h"
+
+#include <stdint.h>
+
+#include <base/bind_helpers.h>
+#include <base/files/file_util.h>
+#include <ipc/ipc_channel.h>
+
+#include "arc_host_messages.h"
+#include "arc_instance_messages.h"
+
+namespace arc {
+
+BridgeEndpoint::BridgeEndpoint() : io_thread_("ARC bridge listener") {
+  io_thread_.StartWithOptions(
+      base::Thread::Options(base::MessageLoop::TYPE_IO, 0));
+}
+
+BridgeEndpoint::~BridgeEndpoint() {}
+
+bool BridgeEndpoint::Connect(const IPC::ChannelHandle& handle,
+                             IPC::Channel::Mode mode) {
+  channel_ = IPC::ChannelProxy::Create(handle, mode, this,
+                                       io_thread_.task_runner().get());
+  if (!channel_)
+    return false;
+
+  return true;
+}
+
+BridgeInstanceEndpoint::BridgeInstanceEndpoint() : BridgeEndpoint() {}
+
+BridgeInstanceEndpoint::~BridgeInstanceEndpoint() {}
+
+bool BridgeInstanceEndpoint::SocketConnect(const char* socket_path) {
+  return BridgeEndpoint::Connect(IPC::ChannelHandle(socket_path),
+                                 IPC::Channel::MODE_NAMED_CLIENT);
+}
+
+bool BridgeInstanceEndpoint::InstanceReady() {
+  return channel_->Send(new ArcHostMsg_InstanceReady());
+}
+
+bool BridgeInstanceEndpoint::OnMessageReceived(const IPC::Message& message) {

[satorux1, 2015/10/23 05:16:43]

should this function run on the io_thread_? Then you can add an assertion here.

    DCHECK(io_thread_.task_runner()->RunsTasksOnCurrentThread());

would probably work.

[Luis Héctor Chávez, 2015/10/23 17:09:24]

No, this is supposed to be processed in the original MessageLoop/Thread. None of
the other implementations of IPC have that assertion FWIW.

[satorux1, 2015/10/26 01:58:52]

I see. In that case, how about adding ThreadChecker instance as a member
variable and use it here (and elsewhere), to ensure that this function is called
in the original thread? 

[satorux1, 2015/10/27 07:10:16]

maybe missed this comment?

[lhc(google), 2015/10/27 08:00:23]

Forgot to reply, but I did add the DCHECKs that the methods were being called in
their original thread.

[satorux1, 2015/10/28 04:57:26]

oops. I didn't noticed about the DCHECKs. thank you for adding them.

+  bool handled = true;
+
+  IPC_BEGIN_MESSAGE_MAP(BridgeInstanceEndpoint, message)
+    IPC_MESSAGE_HANDLER(ArcInstanceMsg_Ping, OnPing)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP()
+
+  if (!handled)
+    LOG(ERROR) << "Invalid message with type = " << message.type();
+  return handled;
+}
+
+void BridgeInstanceEndpoint::OnPing() {
+  channel_->Send(new ArcHostMsg_Pong());
+}
+
+BridgeHostEndpoint::BridgeHostEndpoint() : BridgeEndpoint() {}
+
+BridgeHostEndpoint::~BridgeHostEndpoint() {}
+
+bool BridgeHostEndpoint::SocketConnect(const char* socket_path) {
+  base::FilePath path(socket_path);

[satorux1, 2015/10/23 05:16:43]

Please use base::FilePath::FromUTF8Unsafe() for converting a string into a path
here. FilePath can be 16-bit characters on Windows, which does not matter here,
but I think it's still good to follow Chrome's common practice.

[Luis Héctor Chávez, 2015/10/23 17:09:24]

Done.

+  if (!base::CreateDirectory(path.DirName()))
+    return false;
+
+  if (!BridgeEndpoint::Connect(IPC::ChannelHandle(path.value()),
+                               IPC::Channel::MODE_OPEN_NAMED_SERVER))
+    return false;
+  // TODO(lhchavez): Tighten the security around the socket by tying it to the
+  // user the instance will run as.
+  if (chmod(socket_path, 0777) != 0)

[satorux1, 2015/10/23 05:16:43]

HANDLE_EINTR?

[Luis Héctor Chávez, 2015/10/23 17:09:24]

Done.

+    return false;
+  return true;
+}
+
+bool BridgeHostEndpoint::Ping() {
+  return channel_->Send(new ArcInstanceMsg_Ping());
+}
+
+bool BridgeHostEndpoint::OnMessageReceived(const IPC::Message& message) {
+  bool handled = true;
+
+  IPC_BEGIN_MESSAGE_MAP(BridgeHostEndpoint, message)
+    IPC_MESSAGE_HANDLER(ArcHostMsg_Pong, OnPong)
+    IPC_MESSAGE_HANDLER(ArcHostMsg_InstanceReady, OnInstanceReady)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP()
+
+  if (!handled)
+    LOG(ERROR) << "Invalid message with type = " << message.type();
+  return handled;
+}
+
+}  // namespace arc