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 namespace {
  11
  12 DWORD CalculateIdleTimeInternal() {
  13   LASTINPUTINFO last_input_info = {0};
  14   last_input_info.cbSize = sizeof(LASTINPUTINFO);
  15   DWORD current_idle_time = 0;
  16   if (::GetLastInputInfo(&last_input_info)) {
  17     DWORD now = ::GetTickCount();
  18     if (now < last_input_info.dwTime) {
  19       // GetTickCount() wraps around every 49.7 days -- assume it wrapped just
  20       // once.
  21       const DWORD kMaxDWORD = static_cast<DWORD>(-1);
  22       DWORD time_before_wrap = kMaxDWORD - last_input_info.dwTime;
  23       DWORD time_after_wrap = now;
  24       // The sum is always smaller than kMaxDWORD.
  25       current_idle_time = time_before_wrap + time_after_wrap;
  26     } else {
  27       current_idle_time = now - last_input_info.dwTime;
  28     }
  29
  30     // Convert from ms to seconds.
  31     current_idle_time /= 1000;
  32   }
  33
  34   return current_idle_time;
  35 }
  36
  37 bool IsScreensaverRunning() {
  38   DWORD result = 0;
  39   if (::SystemParametersInfo(SPI_GETSCREENSAVERRUNNING, 0, &result, 0))
  40     return result != FALSE;
  41   return false;
  42 }
  43
  44 bool IsWorkstationLocked() {
  45   bool is_locked = true;
  46   HDESK input_desk = ::OpenInputDesktop(0, 0, GENERIC_READ);
  47   if (input_desk)  {
  48     wchar_t name[256] = {0};
  49     DWORD needed = 0;
  50     if (::GetUserObjectInformation(input_desk,
  51       UOI_NAME,
  52       name,
  53       sizeof(name),
  54       &needed)) {
  55         is_locked = lstrcmpi(name, L"default") != 0;
  56     }
  57     ::CloseDesktop(input_desk);
  58   }
  59   return is_locked;
  60 }
  61
  62 }  // namespace
  63
  64 void CalculateIdleTime(IdleTimeCallback notify) {
  65   notify.Run(static_cast<int>(CalculateIdleTimeInternal()));
  66 }
  67
  68 bool CheckIdleStateIsLocked() {
  69   return IsWorkstationLocked() || IsScreensaverRunning();
  70 }