content/browser/renderer_host/pepper/pepper_gamepad_host.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/browser/renderer_host/pepper/pepper_gamepad_host.h"
   6
   7 #include "base/bind.h"
   8 #include "content/browser/gamepad/gamepad_service.h"
   9 #include "content/public/browser/browser_ppapi_host.h"
  10 #include "ppapi/c/pp_errors.h"
  11 #include "ppapi/host/dispatch_host_message.h"
  12 #include "ppapi/host/host_message_context.h"
  13 #include "ppapi/host/ppapi_host.h"
  14 #include "ppapi/proxy/ppapi_messages.h"
  15 #include "ppapi/shared_impl/ppb_gamepad_shared.h"
  16
  17 namespace content {
  18
  19 PepperGamepadHost::PepperGamepadHost(BrowserPpapiHost* host,
  20                                      PP_Instance instance,
  21                                      PP_Resource resource)
  22     : ResourceHost(host->GetPpapiHost(), instance, resource),
  23       browser_ppapi_host_(host),
  24       gamepad_service_(GamepadService::GetInstance()),
  25       is_started_(false),
  26       weak_factory_(this) {
  27 }
  28
  29 PepperGamepadHost::PepperGamepadHost(GamepadService* gamepad_service,
  30                                      BrowserPpapiHost* host,
  31                                      PP_Instance instance,
  32                                      PP_Resource resource)
  33     : ResourceHost(host->GetPpapiHost(), instance, resource),
  34       browser_ppapi_host_(host),
  35       gamepad_service_(gamepad_service),
  36       is_started_(false),
  37       weak_factory_(this) {
  38 }
  39
  40 PepperGamepadHost::~PepperGamepadHost() {
  41   if (is_started_)
  42     gamepad_service_->RemoveConsumer();
  43 }
  44
  45 int32_t PepperGamepadHost::OnResourceMessageReceived(
  46     const IPC::Message& msg,
  47     ppapi::host::HostMessageContext* context) {
  48   IPC_BEGIN_MESSAGE_MAP(PepperGamepadHost, msg)
  49     PPAPI_DISPATCH_HOST_RESOURCE_CALL_0(PpapiHostMsg_Gamepad_RequestMemory,
  50                                         OnRequestMemory)
  51   IPC_END_MESSAGE_MAP()
  52   return PP_ERROR_FAILED;
  53 }
  54
  55 int32_t PepperGamepadHost::OnRequestMemory(
  56     ppapi::host::HostMessageContext* context) {
  57   if (is_started_)
  58     return PP_ERROR_FAILED;
  59
  60   gamepad_service_->AddConsumer();
  61   is_started_ = true;
  62
  63   // Don't send the shared memory back until the user has interacted with the
  64   // gamepad. This is to prevent fingerprinting and matches what the web
  65   // platform does.
  66   gamepad_service_->RegisterForUserGesture(
  67       base::Bind(&PepperGamepadHost::GotUserGesture,
  68                  weak_factory_.GetWeakPtr(),
  69                  context->MakeReplyMessageContext()));
  70   return PP_OK_COMPLETIONPENDING;
  71 }
  72
  73 void PepperGamepadHost::GotUserGesture(
  74     const ppapi::host::ReplyMessageContext& context) {
  75   base::SharedMemoryHandle handle =
  76       gamepad_service_->GetSharedMemoryHandleForProcess(
  77           browser_ppapi_host_->GetPluginProcessHandle());
  78
  79   context.params.AppendHandle(ppapi::proxy::SerializedHandle(
  80       handle, sizeof(ppapi::ContentGamepadHardwareBuffer)));
  81   host()->SendReply(context, PpapiPluginMsg_Gamepad_SendMemory());
  82 }
  83
  84 }  // namespace content