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 PepperGamepadHost::PepperGamepadHost(GamepadService* gamepad_service,
  29                                      BrowserPpapiHost* host,
  30                                      PP_Instance instance,
  31                                      PP_Resource resource)
  32     : ResourceHost(host->GetPpapiHost(), instance, resource),
  33       browser_ppapi_host_(host),
  34       gamepad_service_(gamepad_service),
  35       is_started_(false),
  36       weak_factory_(this) {}
  37
  38 PepperGamepadHost::~PepperGamepadHost() {
  39   if (is_started_)
  40     gamepad_service_->RemoveConsumer();
  41 }
  42
  43 int32_t PepperGamepadHost::OnResourceMessageReceived(
  44     const IPC::Message& msg,
  45     ppapi::host::HostMessageContext* context) {
  46   IPC_BEGIN_MESSAGE_MAP(PepperGamepadHost, msg)
  47   PPAPI_DISPATCH_HOST_RESOURCE_CALL_0(PpapiHostMsg_Gamepad_RequestMemory,
  48                                       OnRequestMemory)
  49   IPC_END_MESSAGE_MAP()
  50   return PP_ERROR_FAILED;
  51 }
  52
  53 int32_t PepperGamepadHost::OnRequestMemory(
  54     ppapi::host::HostMessageContext* context) {
  55   if (is_started_)
  56     return PP_ERROR_FAILED;
  57
  58   gamepad_service_->AddConsumer();
  59   is_started_ = true;
  60
  61   // Don't send the shared memory back until the user has interacted with the
  62   // gamepad. This is to prevent fingerprinting and matches what the web
  63   // platform does.
  64   gamepad_service_->RegisterForUserGesture(
  65       base::Bind(&PepperGamepadHost::GotUserGesture,
  66                  weak_factory_.GetWeakPtr(),
  67                  context->MakeReplyMessageContext()));
  68   return PP_OK_COMPLETIONPENDING;
  69 }
  70
  71 void PepperGamepadHost::GotUserGesture(
  72     const ppapi::host::ReplyMessageContext& context) {
  73   base::SharedMemoryHandle handle =
  74       gamepad_service_->GetSharedMemoryHandleForProcess(
  75           browser_ppapi_host_->GetPluginProcessHandle());
  76
  77   context.params.AppendHandle(ppapi::proxy::SerializedHandle(
  78       handle, sizeof(ppapi::ContentGamepadHardwareBuffer)));
  79   host()->SendReply(context, PpapiPluginMsg_Gamepad_SendMemory());
  80 }
  81
  82 }  // namespace content