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#include "ui/events/platform/platform_event_source.h"
10
11#include <X11/extensions/Xrandr.h>
12
13namespace ui {
14
15// static
16const int NativeDisplayEventDispatcherX11::kUseCacheAfterStartupMs = 7000;
17
18NativeDisplayEventDispatcherX11::NativeDisplayEventDispatcherX11(
19    NativeDisplayDelegateX11::HelperDelegate* delegate,
20    int xrandr_event_base)
21    : delegate_(delegate),
22      xrandr_event_base_(xrandr_event_base),
23      tick_clock_(new base::DefaultTickClock) {
24  startup_time_ = tick_clock_->NowTicks();
25}
26
27NativeDisplayEventDispatcherX11::~NativeDisplayEventDispatcherX11() {}
28
29bool NativeDisplayEventDispatcherX11::CanDispatchEvent(
30    const PlatformEvent& event) {
31  return (event->type - xrandr_event_base_ == RRScreenChangeNotify) ||
32         (event->type - xrandr_event_base_ == RRNotify);
33}
34
35uint32_t NativeDisplayEventDispatcherX11::DispatchEvent(
36    const PlatformEvent& event) {
37  if (event->type - xrandr_event_base_ == RRScreenChangeNotify) {
38    VLOG(1) << "Received RRScreenChangeNotify event";
39    delegate_->UpdateXRandRConfiguration(event);
40    return ui::POST_DISPATCH_PERFORM_DEFAULT;
41  }
42
43  // Bail out early for everything except RRNotify_OutputChange events
44  // about an output getting connected or disconnected.
45  if (event->type - xrandr_event_base_ != RRNotify)
46    return ui::POST_DISPATCH_PERFORM_DEFAULT;
47  const XRRNotifyEvent* notify_event = reinterpret_cast<XRRNotifyEvent*>(event);
48  if (notify_event->subtype != RRNotify_OutputChange)
49    return ui::POST_DISPATCH_PERFORM_DEFAULT;
50  const XRROutputChangeNotifyEvent* output_change_event =
51      reinterpret_cast<XRROutputChangeNotifyEvent*>(event);
52  const int action = output_change_event->connection;
53  if (action != RR_Connected && action != RR_Disconnected)
54    return ui::POST_DISPATCH_PERFORM_DEFAULT;
55
56  const bool connected = (action == RR_Connected);
57  VLOG(1) << "Received RRNotify_OutputChange event:"
58          << " output=" << output_change_event->output
59          << " crtc=" << output_change_event->crtc
60          << " mode=" << output_change_event->mode
61          << " action=" << (connected ? "connected" : "disconnected");
62
63  bool check_cache = (tick_clock_->NowTicks() - startup_time_)
64                         .InMilliseconds() <= kUseCacheAfterStartupMs;
65
66  if (check_cache) {
67    bool found_changed_output = false;
68    const std::vector<DisplaySnapshot*>& cached_outputs =
69        delegate_->GetCachedDisplays();
70    for (std::vector<DisplaySnapshot*>::const_iterator it =
71             cached_outputs.begin();
72         it != cached_outputs.end();
73         ++it) {
74      const DisplaySnapshotX11* x11_output =
75          static_cast<const DisplaySnapshotX11*>(*it);
76      const DisplayModeX11* x11_mode =
77          static_cast<const DisplayModeX11*>(x11_output->current_mode());
78
79      if (x11_output->output() == output_change_event->output) {
80        if (connected && x11_output->crtc() == output_change_event->crtc &&
81            x11_mode->mode_id() == output_change_event->mode) {
82          VLOG(1) << "Ignoring event describing already-cached state";
83          return POST_DISPATCH_PERFORM_DEFAULT;
84        }
85        found_changed_output = true;
86        break;
87      }
88    }
89
90    if (!connected && !found_changed_output) {
91      VLOG(1) << "Ignoring event describing already-disconnected output";
92      return ui::POST_DISPATCH_PERFORM_DEFAULT;
93    }
94  }
95
96  delegate_->NotifyDisplayObservers();
97
98  return ui::POST_DISPATCH_PERFORM_DEFAULT;
99}
100
101void NativeDisplayEventDispatcherX11::SetTickClockForTest(
102    scoped_ptr<base::TickClock> tick_clock) {
103  tick_clock_ = tick_clock.Pass();
104  startup_time_ = tick_clock_->NowTicks();
105}
106
107}  // namespace ui
108