src/ui/display/chromeos/x11/native_display_event_dispatcher_x11.cc

   1 // Copyright 2014 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 "base/time/default_tick_clock.h"
   6 #include "ui/display/chromeos/x11/native_display_event_dispatcher_x11.h"
   7 #include "ui/display/chromeos/x11/display_mode_x11.h"
   8 #include "ui/display/chromeos/x11/display_snapshot_x11.h"
   9
  10 #include <X11/extensions/Xrandr.h>
  11
  12 namespace ui {
  13
  14 // static
  15 const int NativeDisplayEventDispatcherX11::kUseCacheAfterStartupMs = 7000;
  16
  17 NativeDisplayEventDispatcherX11::NativeDisplayEventDispatcherX11(
  18     NativeDisplayDelegateX11::HelperDelegate* delegate,
  19     int xrandr_event_base)
  20     : delegate_(delegate),
  21       xrandr_event_base_(xrandr_event_base),
  22       tick_clock_(new base::DefaultTickClock) {
  23   startup_time_ = tick_clock_->NowTicks();
  24 }
  25
  26 NativeDisplayEventDispatcherX11::~NativeDisplayEventDispatcherX11() {}
  27
  28 uint32_t NativeDisplayEventDispatcherX11::Dispatch(
  29     const base::NativeEvent& event) {
  30   if (event->type - xrandr_event_base_ == RRScreenChangeNotify) {
  31     VLOG(1) << "Received RRScreenChangeNotify event";
  32     delegate_->UpdateXRandRConfiguration(event);
  33     return POST_DISPATCH_PERFORM_DEFAULT;
  34   }
  35
  36   // Bail out early for everything except RRNotify_OutputChange events
  37   // about an output getting connected or disconnected.
  38   if (event->type - xrandr_event_base_ != RRNotify)
  39     return POST_DISPATCH_PERFORM_DEFAULT;
  40   const XRRNotifyEvent* notify_event = reinterpret_cast<XRRNotifyEvent*>(event);
  41   if (notify_event->subtype != RRNotify_OutputChange)
  42     return POST_DISPATCH_PERFORM_DEFAULT;
  43   const XRROutputChangeNotifyEvent* output_change_event =
  44       reinterpret_cast<XRROutputChangeNotifyEvent*>(event);
  45   const int action = output_change_event->connection;
  46   if (action != RR_Connected && action != RR_Disconnected)
  47     return POST_DISPATCH_PERFORM_DEFAULT;
  48
  49   const bool connected = (action == RR_Connected);
  50   VLOG(1) << "Received RRNotify_OutputChange event:"
  51           << " output=" << output_change_event->output
  52           << " crtc=" << output_change_event->crtc
  53           << " mode=" << output_change_event->mode
  54           << " action=" << (connected ? "connected" : "disconnected");
  55
  56   bool check_cache = (tick_clock_->NowTicks() - startup_time_)
  57                          .InMilliseconds() <= kUseCacheAfterStartupMs;
  58
  59   if (check_cache) {
  60     bool found_changed_output = false;
  61     const std::vector<DisplaySnapshot*>& cached_outputs =
  62         delegate_->GetCachedOutputs();
  63     for (std::vector<DisplaySnapshot*>::const_iterator it =
  64              cached_outputs.begin();
  65          it != cached_outputs.end();
  66          ++it) {
  67       const DisplaySnapshotX11* x11_output =
  68           static_cast<const DisplaySnapshotX11*>(*it);
  69       const DisplayModeX11* x11_mode =
  70           static_cast<const DisplayModeX11*>(x11_output->current_mode());
  71
  72       if (x11_output->output() == output_change_event->output) {
  73         if (connected && x11_output->crtc() == output_change_event->crtc &&
  74             x11_mode->mode_id() == output_change_event->mode) {
  75           VLOG(1) << "Ignoring event describing already-cached state";
  76           return POST_DISPATCH_PERFORM_DEFAULT;
  77         }
  78         found_changed_output = true;
  79         break;
  80       }
  81     }
  82
  83     if (!connected && !found_changed_output) {
  84       VLOG(1) << "Ignoring event describing already-disconnected output";
  85       return POST_DISPATCH_PERFORM_DEFAULT;
  86     }
  87   }
  88
  89   delegate_->NotifyDisplayObservers();
  90
  91   return POST_DISPATCH_PERFORM_DEFAULT;
  92 }
  93
  94 void NativeDisplayEventDispatcherX11::SetTickClockForTest(
  95     scoped_ptr<base::TickClock> tick_clock) {
  96   tick_clock_ = tick_clock.Pass();
  97   startup_time_ = tick_clock_->NowTicks();
  98 }
  99
 100 }  // namespace ui