base/sys_info_android.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 <sys/system_properties.h>
   8
   9 #include "base/logging.h"
  10 #include "base/strings/string_number_conversions.h"
  11 #include "base/strings/string_piece.h"
  12 #include "base/strings/stringprintf.h"
  13
  14 namespace {
  15
  16 // Default version of Android to fall back to when actual version numbers
  17 // cannot be acquired. This is an obviously invalid version number. Code
  18 // doing version comparison should treat it as so and fail all comparisons.
  19 const int kDefaultAndroidMajorVersion = 0;
  20 const int kDefaultAndroidMinorVersion = 0;
  21 const int kDefaultAndroidBugfixVersion = 0;
  22
  23 // Parse out the OS version numbers from the system properties.
  24 void ParseOSVersionNumbers(const char* os_version_str,
  25                            int32 *major_version,
  26                            int32 *minor_version,
  27                            int32 *bugfix_version) {
  28   if (os_version_str[0]) {
  29     // Try to parse out the version numbers from the string.
  30     int num_read = sscanf(os_version_str, "%d.%d.%d", major_version,
  31                           minor_version, bugfix_version);
  32
  33     if (num_read > 0) {
  34       // If we don't have a full set of version numbers, make the extras 0.
  35       if (num_read < 2) *minor_version = 0;
  36       if (num_read < 3) *bugfix_version = 0;
  37       return;
  38     }
  39   }
  40
  41   // For some reason, we couldn't parse the version number string.
  42   *major_version = kDefaultAndroidMajorVersion;
  43   *minor_version = kDefaultAndroidMinorVersion;
  44   *bugfix_version = kDefaultAndroidBugfixVersion;
  45 }
  46
  47 // Parses a system property (specified with unit 'k','m' or 'g').
  48 // Returns a value in bytes.
  49 // Returns -1 if the string could not be parsed.
  50 int64 ParseSystemPropertyBytes(const base::StringPiece& str) {
  51   const int64 KB = 1024;
  52   const int64 MB = 1024 * KB;
  53   const int64 GB = 1024 * MB;
  54   if (str.size() == 0u)
  55     return -1;
  56   int64 unit_multiplier = 1;
  57   size_t length = str.size();
  58   if (str[length - 1] == 'k') {
  59     unit_multiplier = KB;
  60     length--;
  61   } else if (str[length - 1] == 'm') {
  62     unit_multiplier = MB;
  63     length--;
  64   } else if (str[length - 1] == 'g') {
  65     unit_multiplier = GB;
  66     length--;
  67   }
  68   int64 result = 0;
  69   bool parsed = base::StringToInt64(str.substr(0, length), &result);
  70   bool negative = result <= 0;
  71   bool overflow = result >= std::numeric_limits<int64>::max() / unit_multiplier;
  72   if (!parsed || negative || overflow)
  73     return -1;
  74   return result * unit_multiplier;
  75 }
  76
  77 int GetDalvikHeapSizeMB() {
  78   char heap_size_str[PROP_VALUE_MAX];
  79   __system_property_get("dalvik.vm.heapsize", heap_size_str);
  80   // dalvik.vm.heapsize property is writable by a root user.
  81   // Clamp it to reasonable range as a sanity check,
  82   // a typical android device will never have less than 48MB.
  83   const int64 MB = 1024 * 1024;
  84   int64 result = ParseSystemPropertyBytes(heap_size_str);
  85   if (result == -1) {
  86      // We should consider not exposing these values if they are not reliable.
  87      LOG(ERROR) << "Can't parse dalvik.vm.heapsize: " << heap_size_str;
  88      result = base::SysInfo::AmountOfPhysicalMemoryMB() / 3;
  89   }
  90   result = std::min<int64>(std::max<int64>(32 * MB, result), 1024 * MB) / MB;
  91   return static_cast<int>(result);
  92 }
  93
  94 int GetDalvikHeapGrowthLimitMB() {
  95   char heap_size_str[PROP_VALUE_MAX];
  96   __system_property_get("dalvik.vm.heapgrowthlimit", heap_size_str);
  97   // dalvik.vm.heapgrowthlimit property is writable by a root user.
  98   // Clamp it to reasonable range as a sanity check,
  99   // a typical android device will never have less than 24MB.
 100   const int64 MB = 1024 * 1024;
 101   int64 result = ParseSystemPropertyBytes(heap_size_str);
 102   if (result == -1) {
 103      // We should consider not exposing these values if they are not reliable.
 104      LOG(ERROR) << "Can't parse dalvik.vm.heapgrowthlimit: " << heap_size_str;
 105      result = base::SysInfo::AmountOfPhysicalMemoryMB() / 6;
 106   }
 107   result = std::min<int64>(std::max<int64>(16 * MB, result), 512 * MB) / MB;
 108   return static_cast<int>(result);
 109 }
 110
 111 }  // anonymous namespace
 112
 113 namespace base {
 114
 115 std::string SysInfo::OperatingSystemName() {
 116   return "Android";
 117 }
 118
 119 std::string SysInfo::GetAndroidBuildCodename() {
 120   char os_version_codename_str[PROP_VALUE_MAX];
 121   __system_property_get("ro.build.version.codename", os_version_codename_str);
 122   return std::string(os_version_codename_str);
 123 }
 124
 125 std::string SysInfo::GetAndroidBuildID() {
 126   char os_build_id_str[PROP_VALUE_MAX];
 127   __system_property_get("ro.build.id", os_build_id_str);
 128   return std::string(os_build_id_str);
 129 }
 130
 131 std::string SysInfo::GetDeviceName() {
 132   char device_model_str[PROP_VALUE_MAX];
 133   __system_property_get("ro.product.model", device_model_str);
 134   return std::string(device_model_str);
 135 }
 136
 137 std::string SysInfo::OperatingSystemVersion() {
 138   int32 major, minor, bugfix;
 139   OperatingSystemVersionNumbers(&major, &minor, &bugfix);
 140   return StringPrintf("%d.%d.%d", major, minor, bugfix);
 141 }
 142
 143 void SysInfo::OperatingSystemVersionNumbers(int32* major_version,
 144                                             int32* minor_version,
 145                                             int32* bugfix_version) {
 146   // Read the version number string out from the properties.
 147   char os_version_str[PROP_VALUE_MAX];
 148   __system_property_get("ro.build.version.release", os_version_str);
 149
 150   // Parse out the numbers.
 151   ParseOSVersionNumbers(os_version_str, major_version, minor_version,
 152                         bugfix_version);
 153 }
 154
 155 int SysInfo::DalvikHeapSizeMB() {
 156   static int heap_size = GetDalvikHeapSizeMB();
 157   return heap_size;
 158 }
 159
 160 int SysInfo::DalvikHeapGrowthLimitMB() {
 161   static int heap_growth_limit = GetDalvikHeapGrowthLimitMB();
 162   return heap_growth_limit;
 163 }
 164
 165
 166 }  // namespace base