[mojo] Ports EDK

mojo/edk/system/ports_message.cc

+// 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/ports_message.h"
+
+#include "mojo/edk/system/node_channel.h"
+
+namespace mojo {
+namespace edk {
+
+// static
+scoped_ptr<PortsMessage> PortsMessage::NewUserMessage(size_t num_payload_bytes,
+                                                      size_t num_ports,
+                                                      size_t num_handles) {
+  return make_scoped_ptr(
+      new PortsMessage(num_payload_bytes, num_ports, num_handles));
+}
+
+PortsMessage::~PortsMessage() {}
+
+PortsMessage::PortsMessage(size_t num_payload_bytes,
+                           size_t num_ports,
+                           size_t num_handles)
+    : ports::Message(num_payload_bytes, num_ports) {
+  size_t size = num_header_bytes_ + num_ports_bytes_ + num_payload_bytes;
+  void* ptr;
+  channel_message_ = NodeChannel::CreatePortsMessage(size, &ptr, num_handles);
+  InitializeUserMessageHeader(ptr);
+}
+
+PortsMessage::PortsMessage(size_t num_header_bytes,
+                           size_t num_payload_bytes,
+                           size_t num_ports_bytes,
+                           Channel::MessagePtr channel_message)
+    : ports::Message(num_header_bytes,
+                     num_payload_bytes,
+                     num_ports_bytes) {
+  if (channel_message) {
+    channel_message_ = std::move(channel_message);
+    void* data;
+    size_t num_data_bytes;
+    NodeChannel::GetPortsMessageData(channel_message_.get(), &data,
+                                     &num_data_bytes);
+    start_ = static_cast<char*>(data);
+  } else {
+    // TODO: Clean this up. In practice this branch of the constructor should
+    // only be reached from Node-internal calls to AllocMessage, which never
+    // carry ports or non-header bytes.
+    CHECK_EQ(num_payload_bytes, 0u);
+    CHECK_EQ(num_ports_bytes, 0u);
+    void* ptr;
+    channel_message_ =
+        NodeChannel::CreatePortsMessage(num_header_bytes, &ptr, 0);
+    start_ = static_cast<char*>(ptr);
+  }
+}
+
+}  // namespace edk
+}  // namespace mojo