Reland of 'Move content/browser/power_save_blocker to //device/power_save_blocker'

content/browser/power_save_blocker_x11.cc

Index: content/browser/power_save_blocker_x11.cc
diff --git a/content/browser/power_save_blocker_x11.cc b/content/browser/power_save_blocker_x11.cc
deleted file mode 100644
index a177e392ce1466f2469fe0f76908cd1c09959d7d..0000000000000000000000000000000000000000
--- a/content/browser/power_save_blocker_x11.cc
+++ /dev/null
@@ -1,508 +0,0 @@
-// Copyright (c) 2012 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 <X11/Xlib.h>
-#include <X11/extensions/dpms.h>
-#include <X11/extensions/scrnsaver.h>
-#include <stdint.h>
-
-#include <memory>
-
-#include "content/browser/power_save_blocker_impl.h"
-// Xlib #defines Status, but we can't have that for some of our headers.
-#ifdef Status
-#undef Status
-#endif
-
-#include "base/bind.h"
-#include "base/callback.h"
-#include "base/command_line.h"
-#include "base/environment.h"
-#include "base/files/file_path.h"
-#include "base/location.h"
-#include "base/logging.h"
-#include "base/macros.h"
-#include "base/memory/ref_counted.h"
-#include "base/memory/singleton.h"
-#include "base/nix/xdg_util.h"
-#include "base/synchronization/lock.h"
-#include "dbus/bus.h"
-#include "dbus/message.h"
-#include "dbus/object_path.h"
-#include "dbus/object_proxy.h"
-#include "ui/gfx/x/x11_types.h"
-
-namespace {
-
-enum DBusAPI {
-  NO_API,           // Disable. No supported API available.
-  GNOME_API,        // Use the GNOME API. (Supports more features.)
-  FREEDESKTOP_API,  // Use the FreeDesktop API, for KDE4, KDE5, and XFCE.
-};
-
-// Inhibit flags defined in the org.gnome.SessionManager interface.
-// Can be OR'd together and passed as argument to the Inhibit() method
-// to specify which power management features we want to suspend.
-enum GnomeAPIInhibitFlags {
-  INHIBIT_LOGOUT            = 1,
-  INHIBIT_SWITCH_USER       = 2,
-  INHIBIT_SUSPEND_SESSION   = 4,
-  INHIBIT_MARK_SESSION_IDLE = 8
-};
-
-const char kGnomeAPIServiceName[] = "org.gnome.SessionManager";
-const char kGnomeAPIInterfaceName[] = "org.gnome.SessionManager";
-const char kGnomeAPIObjectPath[] = "/org/gnome/SessionManager";
-
-const char kFreeDesktopAPIPowerServiceName[] =
-    "org.freedesktop.PowerManagement";
-const char kFreeDesktopAPIPowerInterfaceName[] =
-    "org.freedesktop.PowerManagement.Inhibit";
-const char kFreeDesktopAPIPowerObjectPath[] =
-    "/org/freedesktop/PowerManagement/Inhibit";
-
-const char kFreeDesktopAPIScreenServiceName[] = "org.freedesktop.ScreenSaver";
-const char kFreeDesktopAPIScreenInterfaceName[] = "org.freedesktop.ScreenSaver";
-const char kFreeDesktopAPIScreenObjectPath[] = "/org/freedesktop/ScreenSaver";
-
-}  // namespace
-
-namespace content {
-
-class PowerSaveBlockerImpl::Delegate
-    : public base::RefCountedThreadSafe<PowerSaveBlockerImpl::Delegate> {
- public:
-  // Picks an appropriate D-Bus API to use based on the desktop environment.
-  Delegate(PowerSaveBlockerType type,
-           const std::string& description,
-           bool freedesktop_only,
-           scoped_refptr<base::SequencedTaskRunner> ui_task_runner,
-           scoped_refptr<base::SingleThreadTaskRunner> blocking_task_runner);
-
-  // Post a task to initialize the delegate on the UI thread, which will itself
-  // then post a task to apply the power save block on the FILE thread.
-  void Init();
-
-  // Post a task to remove the power save block on the FILE thread, unless it
-  // hasn't yet been applied, in which case we just prevent it from applying.
-  void CleanUp();
-
- private:
-  friend class base::RefCountedThreadSafe<Delegate>;
-  ~Delegate() {}
-
-  // Selects an appropriate D-Bus API to use for this object. Must be called on
-  // the UI thread. Checks enqueue_apply_ once an API has been selected, and
-  // enqueues a call back to ApplyBlock() if it is true. See the comments for
-  // enqueue_apply_ below.
-  void InitOnUIThread();
-
-  // Returns true if ApplyBlock() / RemoveBlock() should be called.
-  bool ShouldBlock() const;
-
-  // Apply or remove the power save block, respectively. These methods should be
-  // called once each, on the same thread, per instance. They block waiting for
-  // the action to complete (with a timeout); the thread must thus allow I/O.
-  void ApplyBlock();
-  void RemoveBlock();
-
-  // Asynchronous callback functions for ApplyBlock and RemoveBlock.
-  // Functions do not receive ownership of |response|.
-  void ApplyBlockFinished(dbus::Response* response);
-  void RemoveBlockFinished(dbus::Response* response);
-
-  // Wrapper for XScreenSaverSuspend. Checks whether the X11 Screen Saver
-  // Extension is available first. If it isn't, this is a no-op.
-  // Must be called on the UI thread.
-  void XSSSuspendSet(bool suspend);
-
-  // If DPMS (the power saving system in X11) is not enabled, then we don't want
-  // to try to disable power saving, since on some desktop environments that may
-  // enable DPMS with very poor default settings (e.g. turning off the display
-  // after only 1 second). Must be called on the UI thread.
-  bool DPMSEnabled();
-
-  // If no other method is available (i.e. not running under a Desktop
-  // Environment) check whether the X11 Screen Saver Extension can be used
-  // to disable the screen saver. Must be called on the UI thread.
-  bool XSSAvailable();
-
-  // Returns an appropriate D-Bus API to use based on the desktop environment.
-  // Must be called on the UI thread, as it may call DPMSEnabled() above.
-  DBusAPI SelectAPI();
-
-  const PowerSaveBlockerType type_;
-  const std::string description_;
-  const bool freedesktop_only_;
-
-  // Initially, we post a message to the UI thread to select an API. When it
-  // finishes, it will post a message to the FILE thread to perform the actual
-  // application of the block, unless enqueue_apply_ is false. We set it to
-  // false when we post that message, or when RemoveBlock() is called before
-  // ApplyBlock() has run. Both api_ and enqueue_apply_ are guarded by lock_.
-  DBusAPI api_;
-  bool enqueue_apply_;
-  base::Lock lock_;
-
-  // Indicates that a D-Bus power save blocking request is in flight.
-  bool block_inflight_;
-  // Used to detect erronous redundant calls to RemoveBlock().
-  bool unblock_inflight_;
-  // Indicates that RemoveBlock() is called before ApplyBlock() has finished.
-  // If it's true, then the RemoveBlock() call will be processed immediately
-  // after ApplyBlock() has finished.
-  bool enqueue_unblock_;
-
-  scoped_refptr<dbus::Bus> bus_;
-
-  // The cookie that identifies our inhibit request,
-  // or 0 if there is no active inhibit request.
-  uint32_t inhibit_cookie_;
-
-  scoped_refptr<base::SequencedTaskRunner> ui_task_runner_;
-  scoped_refptr<base::SingleThreadTaskRunner> blocking_task_runner_;
-
-  DISALLOW_COPY_AND_ASSIGN(Delegate);
-};
-
-PowerSaveBlockerImpl::Delegate::Delegate(
-    PowerSaveBlockerType type,
-    const std::string& description,
-    bool freedesktop_only,
-    scoped_refptr<base::SequencedTaskRunner> ui_task_runner,
-    scoped_refptr<base::SingleThreadTaskRunner> blocking_task_runner)
-    : type_(type),
-      description_(description),
-      freedesktop_only_(freedesktop_only),
-      api_(NO_API),
-      enqueue_apply_(false),
-      inhibit_cookie_(0),
-      ui_task_runner_(ui_task_runner),
-      blocking_task_runner_(blocking_task_runner) {
-  // We're on the client's thread here, so we don't allocate the dbus::Bus
-  // object yet. We'll do it later in ApplyBlock(), on the FILE thread.
-}
-
-void PowerSaveBlockerImpl::Delegate::Init() {
-  base::AutoLock lock(lock_);
-  DCHECK(!enqueue_apply_);
-  enqueue_apply_ = true;
-  block_inflight_ = false;
-  unblock_inflight_ = false;
-  enqueue_unblock_ = false;
-  ui_task_runner_->PostTask(FROM_HERE,
-                            base::Bind(&Delegate::InitOnUIThread, this));
-}
-
-void PowerSaveBlockerImpl::Delegate::CleanUp() {
-  base::AutoLock lock(lock_);
-  if (enqueue_apply_) {
-    // If a call to ApplyBlock() has not yet been enqueued because we are still
-    // initializing on the UI thread, then just cancel it. We don't need to
-    // remove the block because we haven't even applied it yet.
-    enqueue_apply_ = false;
-  } else {
-    if (ShouldBlock()) {
-      blocking_task_runner_->PostTask(FROM_HERE,
-                                      base::Bind(&Delegate::RemoveBlock, this));
-    }
-
-    ui_task_runner_->PostTask(
-        FROM_HERE, base::Bind(&Delegate::XSSSuspendSet, this, false));
-  }
-}
-
-void PowerSaveBlockerImpl::Delegate::InitOnUIThread() {
-  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
-  base::AutoLock lock(lock_);
-  api_ = SelectAPI();
-
-  if (enqueue_apply_) {
-    if (ShouldBlock()) {
-      // The thread we use here becomes the origin and D-Bus thread for the
-      // D-Bus library, so we need to use the same thread above for
-      // RemoveBlock(). It must be a thread that allows I/O operations, so we
-      // use the FILE thread.
-      blocking_task_runner_->PostTask(FROM_HERE,
-                                      base::Bind(&Delegate::ApplyBlock, this));
-    }
-    XSSSuspendSet(true);
-  }
-  enqueue_apply_ = false;
-}
-
-bool PowerSaveBlockerImpl::Delegate::ShouldBlock() const {
-  return freedesktop_only_ ? api_ == FREEDESKTOP_API : api_ != NO_API;
-}
-
-void PowerSaveBlockerImpl::Delegate::ApplyBlock() {
-  DCHECK(blocking_task_runner_->RunsTasksOnCurrentThread());
-  DCHECK(!bus_);  // ApplyBlock() should only be called once.
-  DCHECK(!block_inflight_);
-
-  dbus::Bus::Options options;
-  options.bus_type = dbus::Bus::SESSION;
-  options.connection_type = dbus::Bus::PRIVATE;
-  bus_ = new dbus::Bus(options);
-
-  scoped_refptr<dbus::ObjectProxy> object_proxy;
-  std::unique_ptr<dbus::MethodCall> method_call;
-  std::unique_ptr<dbus::MessageWriter> message_writer;
-
-  switch (api_) {
-    case NO_API:
-      NOTREACHED();  // We should never call this method with this value.
-      return;
-    case GNOME_API:
-      object_proxy = bus_->GetObjectProxy(
-          kGnomeAPIServiceName,
-          dbus::ObjectPath(kGnomeAPIObjectPath));
-      method_call.reset(
-          new dbus::MethodCall(kGnomeAPIInterfaceName, "Inhibit"));
-      message_writer.reset(new dbus::MessageWriter(method_call.get()));
-      // The arguments of the method are:
-      //     app_id:        The application identifier
-      //     toplevel_xid:  The toplevel X window identifier
-      //     reason:        The reason for the inhibit
-      //     flags:         Flags that spefify what should be inhibited
-      message_writer->AppendString(
-          base::CommandLine::ForCurrentProcess()->GetProgram().value());
-      message_writer->AppendUint32(0);  // should be toplevel_xid
-      message_writer->AppendString(description_);
-      {
-        uint32_t flags = 0;
-        switch (type_) {
-          case kPowerSaveBlockPreventDisplaySleep:
-            flags |= INHIBIT_MARK_SESSION_IDLE;
-            flags |= INHIBIT_SUSPEND_SESSION;
-            break;
-          case kPowerSaveBlockPreventAppSuspension:
-            flags |= INHIBIT_SUSPEND_SESSION;
-            break;
-        }
-        message_writer->AppendUint32(flags);
-      }
-      break;
-    case FREEDESKTOP_API:
-      switch (type_) {
-        case kPowerSaveBlockPreventDisplaySleep:
-          object_proxy = bus_->GetObjectProxy(
-              kFreeDesktopAPIScreenServiceName,
-              dbus::ObjectPath(kFreeDesktopAPIScreenObjectPath));
-          method_call.reset(new dbus::MethodCall(
-              kFreeDesktopAPIScreenInterfaceName, "Inhibit"));
-          break;
-        case kPowerSaveBlockPreventAppSuspension:
-          object_proxy = bus_->GetObjectProxy(
-              kFreeDesktopAPIPowerServiceName,
-              dbus::ObjectPath(kFreeDesktopAPIPowerObjectPath));
-          method_call.reset(new dbus::MethodCall(
-              kFreeDesktopAPIPowerInterfaceName, "Inhibit"));
-          break;
-      }
-      message_writer.reset(new dbus::MessageWriter(method_call.get()));
-      // The arguments of the method are:
-      //     app_id:        The application identifier
-      //     reason:        The reason for the inhibit
-      message_writer->AppendString(
-          base::CommandLine::ForCurrentProcess()->GetProgram().value());
-      message_writer->AppendString(description_);
-      break;
-  }
-
-  block_inflight_ = true;
-  object_proxy->CallMethod(
-      method_call.get(), dbus::ObjectProxy::TIMEOUT_USE_DEFAULT,
-      base::Bind(&PowerSaveBlockerImpl::Delegate::ApplyBlockFinished, this));
-}
-
-void PowerSaveBlockerImpl::Delegate::ApplyBlockFinished(
-    dbus::Response* response) {
-  DCHECK(blocking_task_runner_->RunsTasksOnCurrentThread());
-  DCHECK(bus_);
-  DCHECK(block_inflight_);
-  block_inflight_ = false;
-
-  if (response) {
-    // The method returns an inhibit_cookie, used to uniquely identify
-    // this request. It should be used as an argument to Uninhibit()
-    // in order to remove the request.
-    dbus::MessageReader message_reader(response);
-    if (!message_reader.PopUint32(&inhibit_cookie_))
-      LOG(ERROR) << "Invalid Inhibit() response: " << response->ToString();
-  } else {
-    LOG(ERROR) << "No response to Inhibit() request!";
-  }
-
-  if (enqueue_unblock_) {
-    enqueue_unblock_ = false;
-    // RemoveBlock() was called while the Inhibit operation was in flight,
-    // so go ahead and remove the block now.
-    blocking_task_runner_->PostTask(FROM_HERE,
-                                    base::Bind(&Delegate::RemoveBlock, this));
-  }
-}
-
-void PowerSaveBlockerImpl::Delegate::RemoveBlock() {
-  DCHECK(blocking_task_runner_->RunsTasksOnCurrentThread());
-  DCHECK(bus_);  // RemoveBlock() should only be called once.
-  DCHECK(!unblock_inflight_);
-
-  if (block_inflight_) {
-    DCHECK(!enqueue_unblock_);
-    // Can't call RemoveBlock until ApplyBlock's async operation has
-    // finished. Enqueue it for execution once ApplyBlock is done.
-    enqueue_unblock_ = true;
-    return;
-  }
-
-  scoped_refptr<dbus::ObjectProxy> object_proxy;
-  std::unique_ptr<dbus::MethodCall> method_call;
-
-  switch (api_) {
-    case NO_API:
-      NOTREACHED();  // We should never call this method with this value.
-      return;
-    case GNOME_API:
-      object_proxy = bus_->GetObjectProxy(
-          kGnomeAPIServiceName,
-          dbus::ObjectPath(kGnomeAPIObjectPath));
-      method_call.reset(
-          new dbus::MethodCall(kGnomeAPIInterfaceName, "Uninhibit"));
-      break;
-    case FREEDESKTOP_API:
-      switch (type_) {
-        case kPowerSaveBlockPreventDisplaySleep:
-          object_proxy = bus_->GetObjectProxy(
-              kFreeDesktopAPIScreenServiceName,
-              dbus::ObjectPath(kFreeDesktopAPIScreenObjectPath));
-          method_call.reset(new dbus::MethodCall(
-              kFreeDesktopAPIScreenInterfaceName, "UnInhibit"));
-          break;
-        case kPowerSaveBlockPreventAppSuspension:
-          object_proxy = bus_->GetObjectProxy(
-              kFreeDesktopAPIPowerServiceName,
-              dbus::ObjectPath(kFreeDesktopAPIPowerObjectPath));
-          method_call.reset(new dbus::MethodCall(
-              kFreeDesktopAPIPowerInterfaceName, "UnInhibit"));
-          break;
-      }
-      break;
-  }
-
-  dbus::MessageWriter message_writer(method_call.get());
-  message_writer.AppendUint32(inhibit_cookie_);
-  unblock_inflight_ = true;
-  object_proxy->CallMethod(
-      method_call.get(), dbus::ObjectProxy::TIMEOUT_USE_DEFAULT,
-      base::Bind(&PowerSaveBlockerImpl::Delegate::RemoveBlockFinished, this));
-}
-
-void PowerSaveBlockerImpl::Delegate::RemoveBlockFinished(
-    dbus::Response* response) {
-  DCHECK(blocking_task_runner_->RunsTasksOnCurrentThread());
-  DCHECK(bus_);
-  unblock_inflight_ = false;
-
-  if (!response)
-    LOG(ERROR) << "No response to Uninhibit() request!";
-  // We don't care about checking the result. We assume it works; we can't
-  // really do anything about it anyway if it fails.
-  inhibit_cookie_ = 0;
-
-  bus_->ShutdownAndBlock();
-  bus_ = nullptr;
-}
-
-void PowerSaveBlockerImpl::Delegate::XSSSuspendSet(bool suspend) {
-  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
-
-  if (!XSSAvailable())
-    return;
-
-  XDisplay* display = gfx::GetXDisplay();
-  XScreenSaverSuspend(display, suspend);
-}
-
-bool PowerSaveBlockerImpl::Delegate::DPMSEnabled() {
-  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
-  XDisplay* display = gfx::GetXDisplay();
-  BOOL enabled = false;
-  int dummy;
-  if (DPMSQueryExtension(display, &dummy, &dummy) && DPMSCapable(display)) {
-    CARD16 state;
-    DPMSInfo(display, &state, &enabled);
-  }
-  return enabled;
-}
-
-bool PowerSaveBlockerImpl::Delegate::XSSAvailable() {
-  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
-  XDisplay* display = gfx::GetXDisplay();
-  int dummy;
-  int major;
-  int minor;
-
-  if (!XScreenSaverQueryExtension(display, &dummy, &dummy))
-    return false;
-
-  if (!XScreenSaverQueryVersion(display, &major, &minor))
-    return false;
-
-  return major > 1 || (major == 1 && minor >= 1);
-}
-
-DBusAPI PowerSaveBlockerImpl::Delegate::SelectAPI() {
-  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
-  std::unique_ptr<base::Environment> env(base::Environment::Create());
-  switch (base::nix::GetDesktopEnvironment(env.get())) {
-    case base::nix::DESKTOP_ENVIRONMENT_GNOME:
-    case base::nix::DESKTOP_ENVIRONMENT_UNITY:
-      if (DPMSEnabled())
-        return GNOME_API;
-      break;
-    case base::nix::DESKTOP_ENVIRONMENT_XFCE:
-    case base::nix::DESKTOP_ENVIRONMENT_KDE4:
-    case base::nix::DESKTOP_ENVIRONMENT_KDE5:
-      if (DPMSEnabled())
-        return FREEDESKTOP_API;
-      break;
-    case base::nix::DESKTOP_ENVIRONMENT_KDE3:
-    case base::nix::DESKTOP_ENVIRONMENT_OTHER:
-      // Not supported.
-      break;
-  }
-  return NO_API;
-}
-
-PowerSaveBlockerImpl::PowerSaveBlockerImpl(
-    PowerSaveBlockerType type,
-    Reason reason,
-    const std::string& description,
-    scoped_refptr<base::SequencedTaskRunner> ui_task_runner,
-    scoped_refptr<base::SingleThreadTaskRunner> blocking_task_runner)
-    : delegate_(new Delegate(type,
-                             description,
-                             false /* freedesktop_only */,
-                             ui_task_runner,
-                             blocking_task_runner)),
-      ui_task_runner_(ui_task_runner),
-      blocking_task_runner_(blocking_task_runner) {
-  delegate_->Init();
-
-  if (type == kPowerSaveBlockPreventDisplaySleep) {
-    freedesktop_suspend_delegate_ = new Delegate(
-        kPowerSaveBlockPreventAppSuspension, description,
-        true /* freedesktop_only */, ui_task_runner, blocking_task_runner);
-    freedesktop_suspend_delegate_->Init();
-  }
-}
-
-PowerSaveBlockerImpl::~PowerSaveBlockerImpl() {
-  delegate_->CleanUp();
-  if (freedesktop_suspend_delegate_)
-    freedesktop_suspend_delegate_->CleanUp();
-}
-
-}  // namespace content