Adds sync brokering to Windows EDK

mojo/edk/system/broker_host_posix.cc

Index: mojo/edk/system/broker_host_posix.cc
diff --git a/mojo/edk/system/broker_host_posix.cc b/mojo/edk/system/broker_host_posix.cc
deleted file mode 100644
index ed8e213c1c0d04a8a3102301861e541473a27276..0000000000000000000000000000000000000000
--- a/mojo/edk/system/broker_host_posix.cc
+++ /dev/null
@@ -1,129 +0,0 @@
-// Copyright 2016 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 "mojo/edk/system/broker_host.h"
-
-#include <fcntl.h>
-#include <unistd.h>
-
-#include <utility>
-
-#include "base/logging.h"
-#include "base/memory/ref_counted.h"
-#include "base/message_loop/message_loop.h"
-#include "base/threading/thread_task_runner_handle.h"
-#include "mojo/edk/embedder/embedder_internal.h"
-#include "mojo/edk/embedder/platform_channel_utils_posix.h"
-#include "mojo/edk/embedder/platform_handle_vector.h"
-#include "mojo/edk/embedder/platform_shared_buffer.h"
-#include "mojo/edk/system/broker_messages.h"
-
-namespace mojo {
-namespace edk {
-
-namespace {
-// To prevent abuse, limit the maximum size of shared memory buffers.
-// TODO(amistry): Re-consider this limit, or do something smarter.
-const size_t kMaxSharedBufferSize = 16 * 1024 * 1024;
-}
-
-BrokerHost::BrokerHost(ScopedPlatformHandle platform_handle) {
-  CHECK(platform_handle.is_valid());
-
-  base::MessageLoop::current()->AddDestructionObserver(this);
-
-  channel_ = Channel::Create(this, std::move(platform_handle),
-                             base::ThreadTaskRunnerHandle::Get());
-  channel_->Start();
-}
-
-BrokerHost::~BrokerHost() {
-  // We're always destroyed on the creation thread, which is the IO thread.
-  base::MessageLoop::current()->RemoveDestructionObserver(this);
-
-  if (channel_)
-    channel_->ShutDown();
-}
-
-void BrokerHost::SendChannel(ScopedPlatformHandle handle) {
-  CHECK(handle.is_valid());
-  CHECK(channel_);
-
-  Channel::MessagePtr message =
-      CreateBrokerMessage(BrokerMessageType::INIT, 1, nullptr);
-  ScopedPlatformHandleVectorPtr handles;
-  handles.reset(new PlatformHandleVector(1));
-  handles->at(0) = handle.release();
-  message->SetHandles(std::move(handles));
-
-  channel_->Write(std::move(message));
-}
-
-void BrokerHost::OnBufferRequest(size_t num_bytes) {
-  scoped_refptr<PlatformSharedBuffer> buffer;
-  scoped_refptr<PlatformSharedBuffer> read_only_buffer;
-  if (num_bytes <= kMaxSharedBufferSize) {
-    buffer = PlatformSharedBuffer::Create(num_bytes);
-    if (buffer)
-      read_only_buffer = buffer->CreateReadOnlyDuplicate();
-    if (!read_only_buffer)
-      buffer = nullptr;
-  } else {
-    LOG(ERROR) << "Shared buffer request too large: " << num_bytes;
-  }
-
-  Channel::MessagePtr message = CreateBrokerMessage(
-      BrokerMessageType::BUFFER_RESPONSE, buffer ? 2 : 0, nullptr);
-  if (buffer) {
-    ScopedPlatformHandleVectorPtr handles;
-    handles.reset(new PlatformHandleVector(2));
-    handles->at(0) = buffer->PassPlatformHandle().release();
-    handles->at(1) = read_only_buffer->PassPlatformHandle().release();
-    message->SetHandles(std::move(handles));
-  }
-
-  channel_->Write(std::move(message));
-}
-
-void BrokerHost::OnChannelMessage(const void* payload,
-                                  size_t payload_size,
-                                  ScopedPlatformHandleVectorPtr handles) {
-  if (payload_size < sizeof(BrokerMessageHeader))
-    return;
-
-  const BrokerMessageHeader* header =
-      static_cast<const BrokerMessageHeader*>(payload);
-  switch (header->type) {
-    case BrokerMessageType::BUFFER_REQUEST:
-      if (payload_size ==
-            sizeof(BrokerMessageHeader) + sizeof(BufferRequestData)) {
-        const BufferRequestData* request =
-            reinterpret_cast<const BufferRequestData*>(header + 1);
-        OnBufferRequest(request->size);
-        return;
-      }
-      break;
-
-    default:
-      break;
-  }
-
-  LOG(ERROR) << "Unexpected broker message type: " << header->type;
-}
-
-void BrokerHost::OnChannelError() {
-  if (channel_) {
-    channel_->ShutDown();
-    channel_ = nullptr;
-  }
-
-  delete this;
-}
-
-void BrokerHost::WillDestroyCurrentMessageLoop() {
-  delete this;
-}
-
-}  // namespace edk
-}  // namespace mojo