Assert both display and system keep-alive on each capture.

media/video/capture/screen/screen_capturer_win.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 "media/video/capture/screen/screen_capturer.h"
 
 #include <windows.h>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 114 matching lines @@
 
   // Rectangle describing the bounds of the desktop device context.
   SkIRect desktop_dc_rect_;
 
   // Class to calculate the difference between two screen bitmaps.
   scoped_ptr<Differ> differ_;
 
   base::ScopedNativeLibrary dwmapi_library_;
   DwmEnableCompositionFunc composition_func_;
 
+  // Used to suppress duplicate logging of SetThreadExecutionState errors.
+  bool set_thread_execution_state_failed_;
+
   DISALLOW_COPY_AND_ASSIGN(ScreenCapturerWin);
 };
 
 // 3780 pixels per meter is equivalent to 96 DPI, typical on desktop monitors.
 static const int kPixelsPerMeter = 3780;
 
 ScreenCaptureFrameWin::ScreenCaptureFrameWin(
     HDC desktop_dc,
     const SkISize& size,
     ScreenCapturer::Delegate* delegate)
@@ skipping 51 matching lines @@
   set_pixels(reinterpret_cast<uint8*>(data));
   set_dimensions(SkISize::Make(bmi.bmiHeader.biWidth,
                                std::abs(bmi.bmiHeader.biHeight)));
   set_bytes_per_row(
       bmi.bmiHeader.biSizeImage / std::abs(bmi.bmiHeader.biHeight));
 }
 
 ScreenCapturerWin::ScreenCapturerWin()
     : delegate_(NULL),
       desktop_dc_rect_(SkIRect::MakeEmpty()),
-      composition_func_(NULL) {
+      composition_func_(NULL),
+      set_thread_execution_state_failed_(false) {
 }
 
 ScreenCapturerWin::~ScreenCapturerWin() {
 }
 
 void ScreenCapturerWin::InvalidateRegion(const SkRegion& invalid_region) {
   helper_.InvalidateRegion(invalid_region);
 }
 
 void ScreenCapturerWin::CaptureFrame() {
   base::Time capture_start_time = base::Time::Now();
 
-  // Force the system to power-up display hardware, if it has been suspended.
-  SetThreadExecutionState(ES_DISPLAY_REQUIRED);
+  // Request that the system not power-down the system, or the display hardware.
+  if (!SetThreadExecutionState(ES_DISPLAY_REQUIRED | ES_SYSTEM_REQUIRED)) {
+    if (!set_thread_execution_state_failed_) {
+      set_thread_execution_state_failed_ = true;
+      LOG_GETLASTERROR(WARNING)
+          << "Failed to make system & display power assertion";
+    }
+  }
 
   // Make sure the GDI capture resources are up-to-date.
   PrepareCaptureResources();
 
   // Copy screen bits to the current buffer.
   CaptureImage();
 
   const ScreenCaptureFrame* current_buffer = queue_.current_frame();
   const ScreenCaptureFrame* last_buffer = queue_.previous_frame();
   if (last_buffer) {
@@ skipping 346 matching lines @@
 void ScreenCapturer::Delegate::ReleaseSharedBuffer(
     scoped_refptr<SharedBuffer> buffer) {
 }
 
 // static
 scoped_ptr<ScreenCapturer> ScreenCapturer::Create() {
   return scoped_ptr<ScreenCapturer>(new ScreenCapturerWin());
 }
 
 }  // namespace media