chrome/browser/idle_win.cc

   1 // Copyright (c) 2011 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 "chrome/browser/idle.h"
   6
   7 #include <limits.h>
   8 #include <windows.h>
   9
  10 #include "ui/base/win/lock_state.h"
  11
  12 namespace {
  13
  14 DWORD CalculateIdleTimeInternal() {
  15   LASTINPUTINFO last_input_info = {0};
  16   last_input_info.cbSize = sizeof(LASTINPUTINFO);
  17   DWORD current_idle_time = 0;
  18   if (::GetLastInputInfo(&last_input_info)) {
  19     DWORD now = ::GetTickCount();
  20     if (now < last_input_info.dwTime) {
  21       // GetTickCount() wraps around every 49.7 days -- assume it wrapped just
  22       // once.
  23       const DWORD kMaxDWORD = static_cast<DWORD>(-1);
  24       DWORD time_before_wrap = kMaxDWORD - last_input_info.dwTime;
  25       DWORD time_after_wrap = now;
  26       // The sum is always smaller than kMaxDWORD.
  27       current_idle_time = time_before_wrap + time_after_wrap;
  28     } else {
  29       current_idle_time = now - last_input_info.dwTime;
  30     }
  31
  32     // Convert from ms to seconds.
  33     current_idle_time /= 1000;
  34   }
  35
  36   return current_idle_time;
  37 }
  38
  39 bool IsScreensaverRunning() {
  40   DWORD result = 0;
  41   if (::SystemParametersInfo(SPI_GETSCREENSAVERRUNNING, 0, &result, 0))
  42     return result != FALSE;
  43   return false;
  44 }
  45
  46 }  // namespace
  47
  48 void CalculateIdleTime(IdleTimeCallback notify) {
  49   notify.Run(static_cast<int>(CalculateIdleTimeInternal()));
  50 }
  51
  52 bool CheckIdleStateIsLocked() {
  53   return ui::IsWorkstationLocked() || IsScreensaverRunning();
  54 }