[Fuchsia] Add support for remote MessagePorts & promote to shared source_set.

Refactors the FIDL/MessagePort adapter classes and adds support for
adapting InterfaceHandle<MessagePort> to Mojo MessagePipes.

Bug: 953958
Change-Id: I9c208cf21bc0956c8f3856e23dbd4302e981abd0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1612351
Commit-Queue: Kevin Marshall <kmarshall@chromium.org>
Reviewed-by: Wez <wez@chromium.org>
Reviewed-by: Marijn Kruisselbrink <mek@chromium.org>
Reviewed-by: Ken Rockot <rockot@google.com>
Cr-Commit-Position: refs/heads/master@{#660647}

fuchsia/base/BUILD.gn

@@ -40,6 +40,23 @@ source_set("modular") {
   ]
 }
 
+# FIDL/Mojo adapters for MessagePorts.
+source_set("message_port") {
+  sources = [
+    "message_port.cc",
+  ]
+  public = [
+    "message_port.h",
+  ]
+  deps = [
+    ":base",
+    "//base",
+    "//mojo/public/cpp/bindings",
+    "//third_party/blink/public/common",
+    "//third_party/fuchsia-sdk/sdk:web",
+  ]
+}
+
 source_set("test_support") {
   testonly = true
   sources = [

fuchsia/base/DEPS

+include_rules = [
+  "+mojo/public",
+  "+third_party/blink/public/common/messaging",
+  "+third_party/blink/public/mojom/messaging",
+]

fuchsia/base/message_port.h

+// Copyright 2018 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 FUCHSIA_BASE_MESSAGE_PORT_H_
+#define FUCHSIA_BASE_MESSAGE_PORT_H_
+
+#include <fuchsia/web/cpp/fidl.h>
+#include <lib/fidl/cpp/binding.h>
+#include <memory>
+
+#include "base/containers/circular_deque.h"
+#include "base/macros.h"
+#include "base/memory/weak_ptr.h"
+#include "mojo/public/cpp/bindings/connector.h"
+#include "mojo/public/cpp/bindings/message.h"
+#include "mojo/public/cpp/system/message_pipe.h"
+
+namespace cr_fuchsia {
+
+// Creates a connected MessagePort from a FIDL MessagePort request and
+// returns a handle to its peer Mojo pipe.
+mojo::ScopedMessagePipeHandle MessagePortFromFidl(
+    fidl::InterfaceRequest<fuchsia::web::MessagePort> fidl_port);
+
+// Creates a connected MessagePort from a remote FIDL MessagePort handle,
+// returns a handle to its peer Mojo pipe.
+mojo::ScopedMessagePipeHandle MessagePortFromFidl(
+    fidl::InterfaceHandle<fuchsia::web::MessagePort> fidl_port);
+
+// Creates a connected MessagePort from a transferred Mojo MessagePort and
+// returns a handle to its FIDL interface peer.
+fidl::InterfaceHandle<fuchsia::web::MessagePort> MessagePortFromMojo(
+    mojo::ScopedMessagePipeHandle mojo_port);
+
+}  // namespace cr_fuchsia
+
+#endif  // FUCHSIA_BASE_MESSAGE_PORT_H_

fuchsia/engine/BUILD.gn

@@ -72,6 +72,7 @@ component("web_engine_core") {
     "//content/public/common",
     "//content/public/renderer",
     "//fuchsia/base",
+    "//fuchsia/base:message_port",
     "//fuchsia/base:modular",
     "//mojo/public/cpp/bindings",
     "//services/network/public/cpp",
@@ -104,8 +105,6 @@ component("web_engine_core") {
     "browser/discarding_event_filter.h",
     "browser/frame_impl.cc",
     "browser/frame_impl.h",
-    "browser/message_port_impl.cc",
-    "browser/message_port_impl.h",
     "browser/web_engine_browser_context.cc",
     "browser/web_engine_browser_context.h",
     "browser/web_engine_browser_main.cc",

fuchsia/engine/browser/frame_impl.cc

@@ -19,8 +19,8 @@
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/was_activated_option.h"
 #include "fuchsia/base/mem_buffer_util.h"
+#include "fuchsia/base/message_port.h"
 #include "fuchsia/engine/browser/context_impl.h"
-#include "fuchsia/engine/browser/message_port_impl.h"
 #include "mojo/public/cpp/system/platform_handle.h"
 #include "third_party/blink/public/common/associated_interfaces/associated_interface_provider.h"
 #include "third_party/blink/public/common/logging/logging_utils.h"
@@ -393,7 +393,7 @@ void FrameImpl::PostMessage(std::string origin,
     for (fuchsia::web::OutgoingTransferable& outgoing :
          *message.mutable_outgoing_transfer()) {
       mojo::ScopedMessagePipeHandle port =
-          MessagePortImpl::FromFidl(std::move(outgoing.message_port()));
+          cr_fuchsia::MessagePortFromFidl(std::move(outgoing.message_port()));
       if (!port) {
         result.set_err(fuchsia::web::FrameError::INTERNAL_ERROR);
         callback(std::move(result));

fuchsia/engine/browser/message_port_impl.cc

-// Copyright 2018 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 "fuchsia/engine/browser/message_port_impl.h"
-
-#include <stdint.h>
-
-#include <lib/fit/function.h>
-#include <memory>
-#include <string>
-#include <utility>
-#include <vector>
-
-#include "base/bind.h"
-#include "base/fuchsia/fuchsia_logging.h"
-#include "base/macros.h"
-#include "fuchsia/base/mem_buffer_util.h"
-#include "mojo/public/cpp/system/message_pipe.h"
-#include "third_party/blink/public/common/messaging/message_port_channel.h"
-#include "third_party/blink/public/common/messaging/string_message_codec.h"
-#include "third_party/blink/public/common/messaging/transferable_message_struct_traits.h"
-#include "third_party/blink/public/mojom/messaging/transferable_message.mojom.h"
-
-namespace {
-
-// Converts a message posted to a JS MessagePort to a WebMessage.
-// Returns an unset Optional<> if the message could not be converted.
-base::Optional<fuchsia::web::WebMessage> FromMojoMessage(
-    mojo::Message message) {
-  fuchsia::web::WebMessage converted;
-
-  blink::TransferableMessage transferable_message;
-  if (!blink::mojom::TransferableMessage::DeserializeFromMessage(
-          std::move(message), &transferable_message))
-    return {};
-
-  if (!transferable_message.ports.empty()) {
-    std::vector<fuchsia::web::IncomingTransferable> transferables;
-    for (const blink::MessagePortChannel& port : transferable_message.ports) {
-      fuchsia::web::IncomingTransferable incoming;
-      incoming.set_message_port(
-          MessagePortImpl::FromMojo(port.ReleaseHandle()));
-      transferables.emplace_back(std::move(incoming));
-    }
-    converted.set_incoming_transfer(std::move(transferables));
-  }
-
-  base::string16 data_utf16;
-  if (!blink::DecodeStringMessage(transferable_message.encoded_message,
-                                  &data_utf16)) {
-    return {};
-  }
-
-  std::string data_utf8;
-  if (!base::UTF16ToUTF8(data_utf16.data(), data_utf16.size(), &data_utf8))
-    return {};
-  base::STLClearObject(&data_utf16);
-
-  fuchsia::mem::Buffer data = cr_fuchsia::MemBufferFromString(data_utf8);
-  if (!data.vmo) {
-    return {};
-  }
-
-  converted.set_data(std::move(data));
-  return converted;
-}
-
-}  // namespace
-
-MessagePortImpl::MessagePortImpl(mojo::ScopedMessagePipeHandle mojo_port)
-    : binding_(this) {
-  connector_ = std::make_unique<mojo::Connector>(
-      std::move(mojo_port), mojo::Connector::SINGLE_THREADED_SEND,
-      base::ThreadTaskRunnerHandle::Get());
-  connector_->set_incoming_receiver(this);
-  connector_->set_connection_error_handler(
-      base::BindOnce(&MessagePortImpl::OnDisconnected, base::Unretained(this)));
-  binding_.set_error_handler([this](zx_status_t status) {
-    ZX_LOG_IF(ERROR, status != ZX_ERR_PEER_CLOSED, status)
-        << " MessagePort disconnected.";
-    OnDisconnected();
-  });
-}
-
-MessagePortImpl::~MessagePortImpl() = default;
-
-void MessagePortImpl::OnDisconnected() {
-  // |connector_| and |binding_| are implicitly unbound.
-  delete this;
-}
-
-void MessagePortImpl::PostMessage(fuchsia::web::WebMessage message,
-                                  PostMessageCallback callback) {
-  fuchsia::web::MessagePort_PostMessage_Result result;
-  if (!message.has_data()) {
-    result.set_err(fuchsia::web::FrameError::NO_DATA_IN_MESSAGE);
-    callback(std::move(result));
-    return;
-  }
-
-  base::string16 data_utf16;
-  if (!cr_fuchsia::ReadUTF8FromVMOAsUTF16(message.data(), &data_utf16)) {
-    result.set_err(fuchsia::web::FrameError::BUFFER_NOT_UTF8);
-    callback(std::move(result));
-    return;
-  }
-
-  blink::TransferableMessage transfer_message;
-  if (message.has_outgoing_transfer()) {
-    for (fuchsia::web::OutgoingTransferable& outgoing :
-         *message.mutable_outgoing_transfer()) {
-      transfer_message.ports.emplace_back(
-          MessagePortImpl::FromFidl(std::move(outgoing.message_port())));
-    }
-  }
-
-  transfer_message.owned_encoded_message =
-      blink::EncodeStringMessage(data_utf16);
-  transfer_message.encoded_message = transfer_message.owned_encoded_message;
-  mojo::Message mojo_message =
-      blink::mojom::TransferableMessage::SerializeAsMessage(&transfer_message);
-
-  CHECK(connector_->Accept(&mojo_message));
-  result.set_response(fuchsia::web::MessagePort_PostMessage_Response());
-  callback(std::move(result));
-}
-
-void MessagePortImpl::ReceiveMessage(
-    fuchsia::web::MessagePort::ReceiveMessageCallback callback) {
-  pending_client_read_cb_ = std::move(callback);
-  MaybeDeliverToClient();
-}
-
-void MessagePortImpl::MaybeDeliverToClient() {
-  // Do nothing if the client hasn't requested a read, or if there's nothing
-  // to read.
-  if (!pending_client_read_cb_ || message_queue_.empty()) {
-    return;
-  }
-
-  auto pending_client_read_cb = std::exchange(pending_client_read_cb_, nullptr);
-  pending_client_read_cb(std::move(message_queue_.front()));
-  message_queue_.pop_front();
-}
-
-bool MessagePortImpl::Accept(mojo::Message* message) {
-  base::Optional<fuchsia::web::WebMessage> message_converted =
-      FromMojoMessage(std::move(*message));
-  if (!message_converted) {
-    DLOG(ERROR) << "Couldn't decode MessageChannel from Mojo pipe.";
-    return false;
-  }
-  message_queue_.emplace_back(std::move(message_converted.value()));
-  MaybeDeliverToClient();
-  return true;
-}
-
-// static
-mojo::ScopedMessagePipeHandle MessagePortImpl::FromFidl(
-    fidl::InterfaceRequest<fuchsia::web::MessagePort> port) {
-  mojo::ScopedMessagePipeHandle client_port;
-  mojo::ScopedMessagePipeHandle content_port;
-  mojo::CreateMessagePipe(0, &content_port, &client_port);
-
-  MessagePortImpl* port_impl = new MessagePortImpl(std::move(client_port));
-  port_impl->binding_.Bind(std::move(port));
-
-  return content_port;
-}
-
-// static
-fidl::InterfaceHandle<fuchsia::web::MessagePort> MessagePortImpl::FromMojo(
-    mojo::ScopedMessagePipeHandle port) {
-  MessagePortImpl* created_port = new MessagePortImpl(std::move(port));
-  return created_port->binding_.NewBinding();
-}

fuchsia/engine/browser/message_port_impl.h

-// Copyright 2018 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 FUCHSIA_ENGINE_BROWSER_MESSAGE_PORT_IMPL_H_
-#define FUCHSIA_ENGINE_BROWSER_MESSAGE_PORT_IMPL_H_
-
-#include <fuchsia/web/cpp/fidl.h>
-#include <lib/fidl/cpp/binding.h>
-#include <memory>
-
-#include "base/containers/circular_deque.h"
-#include "base/macros.h"
-#include "base/memory/weak_ptr.h"
-#include "mojo/public/cpp/bindings/connector.h"
-#include "mojo/public/cpp/bindings/message.h"
-#include "mojo/public/cpp/system/message_pipe.h"
-
-// Defines the implementation of a MessagePort which routes messages from
-// FIDL clients to web content, or vice versa. Every MessagePortImpl has a FIDL
-// port and a Mojo port.
-//
-// MessagePortImpl instances are self-managed; they destroy themselves when
-// the connection is terminated from either the Mojo or FIDL side.
-class MessagePortImpl : public fuchsia::web::MessagePort,
-                        public mojo::MessageReceiver {
- public:
-  // Creates a connected MessagePort from a FIDL MessagePort request and
-  // returns a handle to its peer Mojo pipe.
-  static mojo::ScopedMessagePipeHandle FromFidl(
-      fidl::InterfaceRequest<fuchsia::web::MessagePort> port);
-
-  // Creates a connected MessagePort from a transferred Mojo MessagePort and
-  // returns a handle to its FIDL interface peer.
-  static fidl::InterfaceHandle<fuchsia::web::MessagePort> FromMojo(
-      mojo::ScopedMessagePipeHandle port);
-
- private:
-  explicit MessagePortImpl(mojo::ScopedMessagePipeHandle mojo_port);
-
-  // Non-public to ensure that only this object may destroy itself.
-  ~MessagePortImpl() override;
-
-  // fuchsia::web::MessagePort implementation.
-  void PostMessage(fuchsia::web::WebMessage message,
-                   PostMessageCallback callback) override;
-  void ReceiveMessage(ReceiveMessageCallback callback) override;
-
-  // Called when the connection to Blink or FIDL is terminated.
-  void OnDisconnected();
-
-  // Sends the next message enqueued in |message_queue_| to the client,
-  // if the client has requested a message.
-  void MaybeDeliverToClient();
-
-  // mojo::MessageReceiver implementation.
-  bool Accept(mojo::Message* message) override;
-
-  fidl::Binding<fuchsia::web::MessagePort> binding_;
-  base::circular_deque<fuchsia::web::WebMessage> message_queue_;
-  ReceiveMessageCallback pending_client_read_cb_;
-  std::unique_ptr<mojo::Connector> connector_;
-
-  DISALLOW_COPY_AND_ASSIGN(MessagePortImpl);
-};
-
-#endif  // FUCHSIA_ENGINE_BROWSER_MESSAGE_PORT_IMPL_H_