Revert 111189 - Add gamepad hardware data fetcher, and higher level thread container

content/browser/gamepad/gamepad_provider.cc

Index: content/browser/gamepad/gamepad_provider.cc
===================================================================
--- content/browser/gamepad/gamepad_provider.cc	(revision 111220)
+++ content/browser/gamepad/gamepad_provider.cc	(working copy)
@@ -1,145 +0,0 @@
-// 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 <cmath>
-#include <set>
-#include <vector>
-
-#include "base/bind.h"
-#include "base/logging.h"
-#include "base/message_loop.h"
-#include "base/task.h"
-#include "base/threading/thread.h"
-#include "base/threading/thread_restrictions.h"
-#include "content/public/browser/browser_thread.h"
-#include "content/browser/gamepad/gamepad_provider.h"
-#include "content/browser/gamepad/data_fetcher.h"
-#include "content/common/gamepad_messages.h"
-
-#if defined(OS_WIN)
-#include "content/browser/gamepad/data_fetcher_win.h"
-#endif
-
-namespace gamepad {
-
-Provider* Provider::instance_ = NULL;
-
-using namespace content;
-
-// Define the default data fetcher that Provider will use if none is supplied.
-// (PlatformDataFetcher).
-#if defined(OS_WIN)
-
-typedef DataFetcherWindows PlatformDataFetcher;
-
-#else
-
-class EmptyDataFetcher : public DataFetcher {
- public:
-  void GetGamepadData(WebKit::WebGamepads* pads, bool) {
-    pads->length = 0;
-  }
-};
-typedef EmptyDataFetcher PlatformDataFetcher;
-
-#endif
-
-Provider::Provider(DataFetcher* fetcher)
-    : creator_loop_(MessageLoop::current()->message_loop_proxy()),
-      provided_fetcher_(fetcher),
-      devices_changed_(true),
-      ALLOW_THIS_IN_INITIALIZER_LIST(weak_factory_(this)) {
-  size_t data_size = sizeof(GamepadHardwareBuffer);
-  base::SystemMonitor* monitor = base::SystemMonitor::Get();
-  if (monitor)
-    monitor->AddDevicesChangedObserver(this);
-  gamepad_shared_memory_.CreateAndMapAnonymous(data_size);
-  GamepadHardwareBuffer* hwbuf = SharedMemoryAsHardwareBuffer();
-  memset(hwbuf, 0, sizeof(GamepadHardwareBuffer));
-}
-
-Provider::~Provider() {
-  base::SystemMonitor* monitor = base::SystemMonitor::Get();
-  if (monitor)
-    monitor->RemoveDevicesChangedObserver(this);
-  Stop();
-}
-
-base::SharedMemoryHandle Provider::GetRendererSharedMemoryHandle(
-    base::ProcessHandle process) {
-  base::SharedMemoryHandle renderer_handle;
-  gamepad_shared_memory_.ShareToProcess(process, &renderer_handle);
-  return renderer_handle;
-}
-
-void Provider::OnDevicesChanged() {
-  devices_changed_ = true;
-}
-
-void Provider::Start() {
-  DCHECK(MessageLoop::current()->message_loop_proxy() == creator_loop_);
-
-  if (polling_thread_.get())
-    return;
-
-  polling_thread_.reset(new base::Thread("Gamepad polling thread"));
-  if (!polling_thread_->Start()) {
-    LOG(ERROR) << "Failed to start gamepad polling thread";
-    polling_thread_.reset();
-    return;
-  }
-
-  MessageLoop* polling_loop = polling_thread_->message_loop();
-  polling_loop->PostTask(
-      FROM_HERE,
-      base::Bind(&Provider::DoInitializePollingThread, this));
-}
-
-void Provider::Stop() {
-  DCHECK(MessageLoop::current()->message_loop_proxy() == creator_loop_);
-
-  polling_thread_.reset();
-  data_fetcher_.reset();
-}
-
-void Provider::DoInitializePollingThread() {
-  DCHECK(MessageLoop::current() == polling_thread_->message_loop());
-
-  if (!provided_fetcher_.get())
-    provided_fetcher_.reset(new PlatformDataFetcher);
-
-  // Pass ownership of fetcher to provider_.
-  data_fetcher_.swap(provided_fetcher_);
-
-  // Start polling.
-  ScheduleDoPoll();
-}
-
-void Provider::DoPoll() {
-  DCHECK(MessageLoop::current() == polling_thread_->message_loop());
-  GamepadHardwareBuffer* hwbuf = SharedMemoryAsHardwareBuffer();
-  base::subtle::Barrier_AtomicIncrement(&hwbuf->start_marker, 1);
-  data_fetcher_->GetGamepadData(&hwbuf->buffer, devices_changed_);
-  base::subtle::Barrier_AtomicIncrement(&hwbuf->end_marker, 1);
-  devices_changed_ = false;
-  // Schedule our next interval of polling.
-  ScheduleDoPoll();
-}
-
-void Provider::ScheduleDoPoll() {
-  DCHECK(MessageLoop::current() == polling_thread_->message_loop());
-
-  MessageLoop::current()->PostDelayedTask(
-      FROM_HERE,
-      base::Bind(&Provider::DoPoll, weak_factory_.GetWeakPtr()),
-      kDesiredSamplingIntervalMs);
-}
-
-GamepadHardwareBuffer* Provider::SharedMemoryAsHardwareBuffer() {
-  void* mem = gamepad_shared_memory_.memory();
-  DCHECK(mem);
-  return static_cast<GamepadHardwareBuffer*>(mem);
-}
-
-}  // namespace gamepad