1 files changed, 91 insertions, 0 deletions
diff --git a/chromium/third_party/webrtc/modules/desktop_capture/mac/desktop_configuration_monitor.cc b/chromium/third_party/webrtc/modules/desktop_capture/mac/desktop_configuration_monitor.cc
new file mode 100644
index 00000000000..f0d5c34be65
--- /dev/null
+++ b/chromium/third_party/webrtc/modules/desktop_capture/mac/desktop_configuration_monitor.cc
@@ -0,0 +1,91 @@
+/*
+ *  Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/modules/desktop_capture/mac/desktop_configuration_monitor.h"
+
+#include "webrtc/modules/desktop_capture/mac/desktop_configuration.h"
+#include "webrtc/system_wrappers/interface/event_wrapper.h"
+#include "webrtc/system_wrappers/interface/logging.h"
+
+namespace webrtc {
+
+// The amount of time allowed for displays to reconfigure.
+static const int64_t kDisplayConfigurationEventTimeoutMs = 10 * 1000;
+
+DesktopConfigurationMonitor::DesktopConfigurationMonitor()
+    : ref_count_(0),
+      display_configuration_capture_event_(EventWrapper::Create()) {
+  CGError err = CGDisplayRegisterReconfigurationCallback(
+      DesktopConfigurationMonitor::DisplaysReconfiguredCallback, this);
+  if (err != kCGErrorSuccess) {
+    LOG(LS_ERROR) << "CGDisplayRegisterReconfigurationCallback " << err;
+    abort();
+  }
+  display_configuration_capture_event_->Set();
+
+  desktop_configuration_ = MacDesktopConfiguration::GetCurrent(
+      MacDesktopConfiguration::TopLeftOrigin);
+}
+
+DesktopConfigurationMonitor::~DesktopConfigurationMonitor() {
+  CGError err = CGDisplayRemoveReconfigurationCallback(
+      DesktopConfigurationMonitor::DisplaysReconfiguredCallback, this);
+  if (err != kCGErrorSuccess)
+    LOG(LS_ERROR) << "CGDisplayRemoveReconfigurationCallback " << err;
+}
+
+void DesktopConfigurationMonitor::Lock() {
+  if (!display_configuration_capture_event_->Wait(
+              kDisplayConfigurationEventTimeoutMs)) {
+    LOG_F(LS_ERROR) << "Event wait timed out.";
+    abort();
+  }
+}
+
+void DesktopConfigurationMonitor::Unlock() {
+  display_configuration_capture_event_->Set();
+}
+
+// static
+void DesktopConfigurationMonitor::DisplaysReconfiguredCallback(
+    CGDirectDisplayID display,
+    CGDisplayChangeSummaryFlags flags,
+    void *user_parameter) {
+  DesktopConfigurationMonitor* monitor =
+      reinterpret_cast<DesktopConfigurationMonitor*>(user_parameter);
+  monitor->DisplaysReconfigured(display, flags);
+}
+
+void DesktopConfigurationMonitor::DisplaysReconfigured(
+    CGDirectDisplayID display,
+    CGDisplayChangeSummaryFlags flags) {
+  if (flags & kCGDisplayBeginConfigurationFlag) {
+    if (reconfiguring_displays_.empty()) {
+      // If this is the first display to start reconfiguring then wait on
+      // |display_configuration_capture_event_| to block the capture thread
+      // from accessing display memory until the reconfiguration completes.
+      if (!display_configuration_capture_event_->Wait(
+              kDisplayConfigurationEventTimeoutMs)) {
+        LOG_F(LS_ERROR) << "Event wait timed out.";
+        abort();
+      }
+    }
+    reconfiguring_displays_.insert(display);
+  } else {
+    reconfiguring_displays_.erase(display);
+    if (reconfiguring_displays_.empty()) {
+      desktop_configuration_ = MacDesktopConfiguration::GetCurrent(
+          MacDesktopConfiguration::TopLeftOrigin);
+      display_configuration_capture_event_->Set();
+    }
+  }
+}
+
+}  // namespace webrtc