Allow renderer to create pepper ResourceHosts in the browser

content/renderer/pepper/pepper_browser_connection.cc

+// Copyright (c) 2011 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 "content/renderer/pepper/pepper_browser_connection.h"
+
+#include <limits>
+
+#include "base/logging.h"
+#include "ipc/ipc_message_macros.h"
+#include "ppapi/proxy/ppapi_messages.h"
+#include "ppapi/proxy/resource_message_params.h"
+
+namespace content {
+
+PepperBrowserConnection::PepperBrowserConnection(RenderView* render_view)
+    : RenderViewObserver(render_view),
+      next_sequence_number_(1) {
+}
+
+PepperBrowserConnection::~PepperBrowserConnection() {
+}
+
+bool PepperBrowserConnection::OnMessageReceived(const IPC::Message& msg) {
+  bool handled = true;
+  IPC_BEGIN_MESSAGE_MAP(PepperBrowserConnection, msg)
+    IPC_MESSAGE_HANDLER(PpapiHostMsg_CreateResourceHostFromHostReply,
+                        OnMsgCreateResourceHostFromHostReply)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP()
+
+  return handled;
+}
+
+void PepperBrowserConnection::SendBrowserCreate(
+    int child_process_id,
+    PP_Instance instance,
+    const IPC::Message& nested_msg,
+    PendingResourceIDCallback callback) {
+  int32_t sequence_number = GetNextSequence();
+  pending_create_map_[sequence_number] = callback;
+  ppapi::proxy::ResourceMessageCallParams params(0, sequence_number);
+  Send(new PpapiHostMsg_CreateResourceHostFromHost(
+      child_process_id, params, instance, nested_msg));
+}
+
+void PepperBrowserConnection::OnMsgCreateResourceHostFromHostReply(
+    int32_t sequence_number,
+    int pending_resource_host_id) {
+  // Check that the message is destined for the plugin this object is associated
+  // with.
+  std::map<int32_t, PendingResourceIDCallback>::iterator it =
+      pending_create_map_.find(sequence_number);
+  if (it != pending_create_map_.end()) {
+    it->second.Run(pending_resource_host_id);
+    pending_create_map_.erase(it);
+  } else {
+    NOTREACHED();
+  }
+}
+
+int32_t PepperBrowserConnection::GetNextSequence() {
+  // Return the value with wraparound, making sure we don't make a sequence
+  // number with a 0 ID. Note that signed wraparound is undefined in C++ so we
+  // manually check.
+  int32_t ret = next_sequence_number_;
+  if (next_sequence_number_ == std::numeric_limits<int32_t>::max())
+    next_sequence_number_ = 1;  // Skip 0 which is invalid.
+  else
+    next_sequence_number_++;
+  return ret;
+}
+
+}  // namespace content