1 /*
2 * Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 #include "webrtc/modules/desktop_capture/mac/desktop_configuration_monitor.h"
12
13 #include "webrtc/modules/desktop_capture/mac/desktop_configuration.h"
14 #include "webrtc/system_wrappers/include/event_wrapper.h"
15 #include "webrtc/system_wrappers/include/logging.h"
16
17 namespace webrtc {
18
19 // The amount of time allowed for displays to reconfigure.
20 static const int64_t kDisplayConfigurationEventTimeoutMs = 10 * 1000;
21
DesktopConfigurationMonitor()22 DesktopConfigurationMonitor::DesktopConfigurationMonitor()
23 : ref_count_(0),
24 display_configuration_capture_event_(EventWrapper::Create()) {
25 CGError err = CGDisplayRegisterReconfigurationCallback(
26 DesktopConfigurationMonitor::DisplaysReconfiguredCallback, this);
27 if (err != kCGErrorSuccess) {
28 LOG(LS_ERROR) << "CGDisplayRegisterReconfigurationCallback " << err;
29 abort();
30 }
31 display_configuration_capture_event_->Set();
32
33 desktop_configuration_ = MacDesktopConfiguration::GetCurrent(
34 MacDesktopConfiguration::TopLeftOrigin);
35 }
36
~DesktopConfigurationMonitor()37 DesktopConfigurationMonitor::~DesktopConfigurationMonitor() {
38 CGError err = CGDisplayRemoveReconfigurationCallback(
39 DesktopConfigurationMonitor::DisplaysReconfiguredCallback, this);
40 if (err != kCGErrorSuccess)
41 LOG(LS_ERROR) << "CGDisplayRemoveReconfigurationCallback " << err;
42 }
43
Lock()44 void DesktopConfigurationMonitor::Lock() {
45 if (!display_configuration_capture_event_->Wait(
46 kDisplayConfigurationEventTimeoutMs)) {
47 LOG_F(LS_ERROR) << "Event wait timed out.";
48 abort();
49 }
50 }
51
Unlock()52 void DesktopConfigurationMonitor::Unlock() {
53 display_configuration_capture_event_->Set();
54 }
55
56 // static
DisplaysReconfiguredCallback(CGDirectDisplayID display,CGDisplayChangeSummaryFlags flags,void * user_parameter)57 void DesktopConfigurationMonitor::DisplaysReconfiguredCallback(
58 CGDirectDisplayID display,
59 CGDisplayChangeSummaryFlags flags,
60 void *user_parameter) {
61 DesktopConfigurationMonitor* monitor =
62 reinterpret_cast<DesktopConfigurationMonitor*>(user_parameter);
63 monitor->DisplaysReconfigured(display, flags);
64 }
65
DisplaysReconfigured(CGDirectDisplayID display,CGDisplayChangeSummaryFlags flags)66 void DesktopConfigurationMonitor::DisplaysReconfigured(
67 CGDirectDisplayID display,
68 CGDisplayChangeSummaryFlags flags) {
69 if (flags & kCGDisplayBeginConfigurationFlag) {
70 if (reconfiguring_displays_.empty()) {
71 // If this is the first display to start reconfiguring then wait on
72 // |display_configuration_capture_event_| to block the capture thread
73 // from accessing display memory until the reconfiguration completes.
74 if (!display_configuration_capture_event_->Wait(
75 kDisplayConfigurationEventTimeoutMs)) {
76 LOG_F(LS_ERROR) << "Event wait timed out.";
77 abort();
78 }
79 }
80 reconfiguring_displays_.insert(display);
81 } else {
82 reconfiguring_displays_.erase(display);
83 if (reconfiguring_displays_.empty()) {
84 desktop_configuration_ = MacDesktopConfiguration::GetCurrent(
85 MacDesktopConfiguration::TopLeftOrigin);
86 display_configuration_capture_event_->Set();
87 }
88 }
89 }
90
91 } // namespace webrtc
92