Pepper API implementation for output protection.

chromeos/display/output_configurator.cc

 // 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 "chromeos/display/output_configurator.h"
 
 #include <X11/Xlib.h>
 #include <X11/extensions/Xrandr.h>
 #include <X11/extensions/XInput2.h>
 
@@ skipping 216 matching lines @@
       new_state, power_state_, outputs);
 
   // Force the DPMS on chrome startup as the driver doesn't always detect
   // that all displays are on when signing out.
   delegate_->ForceDPMSOn();
   delegate_->UngrabServer();
   delegate_->SendProjectingStateToPowerManager(IsProjecting(outputs));
   NotifyObservers(success, new_state);
 }
 
+bool OutputConfigurator::QueryOutputProtectionStatus(
+    chrome::PepperOutputProtectionHost* client,
+    uint32_t* link_mask,
+    uint32_t* protection_mask) {
+  if (!configure_display_)
+    return false;
+
+  delegate_->GrabServer();
+  bool result = delegate_->QueryOutputProtectionStatus(client, link_mask,
+                                                       protection_mask);
+  delegate_->UngrabServer();

[dmichael (off chromium), 2013/09/09 20:37:15]

I don't know anything about that delegate or what GrabServer/UngrabServer does,
but it would be nice if that delegate defined a scoped sentinel to make sure
UngrabServer is called when exiting scope. To prevent mistakes if functions can
return early.

I.e. something you could use like this:
{
  ScopedServerGrabber grab_server(delegate_);
  // Do something with delegate_
} // UngrabServer gets called automatically.

[kcwu, 2013/09/10 12:50:21]

Agree. However there are 4 existing GrabServer() in this file works this way. Do
you suggest me refactor them or just follow them?

[dmichael (off chromium), 2013/09/11 18:22:45]

Following them is fine. But it's worth considering a follow-up CL.

[kcwu, 2013/09/12 18:22:08]

Thanks

+  return result;
+}
+
+bool OutputConfigurator::EnableOutputProtection(
+    chrome::PepperOutputProtectionHost* client,
+    uint32_t desired_method_mask) {
+  if (!configure_display_)
+    return false;
+
+  delegate_->GrabServer();
+  bool result = delegate_->EnableOutputProtection(client, desired_method_mask);
+  delegate_->UngrabServer();
+  return result;
+}
+
 void OutputConfigurator::Stop() {
   configure_display_ = false;
 }
 
 bool OutputConfigurator::SetDisplayPower(DisplayPowerState power_state,
                                          int flags) {
   if (!configure_display_)
     return false;
 
   VLOG(1) << "SetDisplayPower: power_state="
@@ skipping 452 matching lines @@
   float width_ratio = static_cast<float>(mirror_mode_info->width) /
       static_cast<float>(native_mode_info->width);
   float height_ratio = static_cast<float>(mirror_mode_info->height) /
       static_cast<float>(native_mode_info->height);
 
   area_ratio = width_ratio * height_ratio;
   return area_ratio;
 }
 
 }  // namespace chromeos