base/sys_info.cc

   1 // Copyright (c) 2012 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 "base/sys_info.h"
   6
   7 #include "base/base_switches.h"
   8 #include "base/command_line.h"
   9 #include "base/lazy_instance.h"
  10 #include "base/strings/string_number_conversions.h"
  11 #include "base/sys_info_internal.h"
  12 #include "base/time/time.h"
  13
  14 namespace base {
  15
  16 #if !defined(OS_ANDROID)
  17
  18 static const int kLowMemoryDeviceThresholdMB = 512;
  19
  20 bool DetectLowEndDevice() {
  21   CommandLine* command_line = CommandLine::ForCurrentProcess();
  22   if (command_line->HasSwitch(switches::kEnableLowEndDeviceMode))
  23     return true;
  24   if (command_line->HasSwitch(switches::kDisableLowEndDeviceMode))
  25     return false;
  26
  27   int ram_size_mb = SysInfo::AmountOfPhysicalMemoryMB();
  28   return (ram_size_mb > 0 && ram_size_mb < kLowMemoryDeviceThresholdMB);
  29 }
  30
  31 static LazyInstance<
  32   internal::LazySysInfoValue<bool, DetectLowEndDevice> >::Leaky
  33   g_lazy_low_end_device = LAZY_INSTANCE_INITIALIZER;
  34
  35 // static
  36 bool SysInfo::IsLowEndDevice() {
  37   return g_lazy_low_end_device.Get().value();
  38 }
  39 #endif
  40
  41 #if !defined(OS_MACOSX) || defined(OS_IOS)
  42 std::string SysInfo::HardwareModelName() {
  43   return std::string();
  44 }
  45 #endif
  46
  47 // static
  48 int64 SysInfo::Uptime() {
  49   // This code relies on an implementation detail of TimeTicks::Now() - that
  50   // its return value happens to coincide with the system uptime value in
  51   // microseconds, on Win/Mac/iOS/Linux/ChromeOS and Android.
  52   int64 uptime_in_microseconds = TimeTicks::Now().ToInternalValue();
  53   return uptime_in_microseconds / 1000;
  54 }
  55
  56 }  // namespace base