[Android] Remove deprecated SysInfo property retrieval

base/sys_info_android.cc

Index: base/sys_info_android.cc
diff --git a/base/sys_info_android.cc b/base/sys_info_android.cc
index c288ae2fe87f7ce3e68edb513bd2c5c45849ef83..fd158e3b4d776c2cd6dd8f0228d8454877faf356 100644
--- a/base/sys_info_android.cc
+++ b/base/sys_info_android.cc
@@ -4,55 +4,13 @@
 
 #include "base/sys_info.h"
 
-#include <dlfcn.h>
-#include <sys/system_properties.h>
-
+#include "base/android/build_info.h"
 #include "base/android/sys_utils.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
-#include "base/strings/string_piece.h"
-#include "base/strings/stringprintf.h"
 #include "base/sys_info_internal.h"
 
-#if (__ANDROID_API__ >= 21 /* 5.0 - Lollipop */)
-
-namespace {
-
-typedef int (SystemPropertyGetFunction)(const char*, char*);
-
-SystemPropertyGetFunction* DynamicallyLoadRealSystemPropertyGet() {
-  // libc.so should already be open, get a handle to it.
-  void* handle = dlopen("libc.so", RTLD_NOLOAD);
-  if (!handle) {
-    LOG(FATAL) << "Cannot dlopen libc.so: " << dlerror();
-  }
-  SystemPropertyGetFunction* real_system_property_get =
-      reinterpret_cast<SystemPropertyGetFunction*>(
-          dlsym(handle, "__system_property_get"));
-  if (!real_system_property_get) {
-    LOG(FATAL) << "Cannot resolve __system_property_get(): " << dlerror();
-  }
-  return real_system_property_get;
-}
-
-static base::LazyInstance<base::internal::LazySysInfoValue<
-    SystemPropertyGetFunction*, DynamicallyLoadRealSystemPropertyGet> >::Leaky
-    g_lazy_real_system_property_get = LAZY_INSTANCE_INITIALIZER;
-
-}  // namespace
-
-// Android 'L' removes __system_property_get from the NDK, however it is still
-// a hidden symbol in libc. Until we remove all calls of __system_property_get
-// from Chrome we work around this by defining a weak stub here, which uses
-// dlsym to but ensures that Chrome uses the real system
-// implementatation when loaded.  http://crbug.com/392191.
-BASE_EXPORT int __system_property_get(const char* name, char* value) {
-  return g_lazy_real_system_property_get.Get().value()(name, value);
-}
-
-#endif
-
 namespace {
 
 // Default version of Android to fall back to when actual version numbers
@@ -87,68 +45,16 @@ void ParseOSVersionNumbers(const char* os_version_str,
   *bugfix_version = kDefaultAndroidBugfixVersion;
 }
 
-// Parses a system property (specified with unit 'k','m' or 'g').
-// Returns a value in bytes.
-// Returns -1 if the string could not be parsed.
-int64 ParseSystemPropertyBytes(const base::StringPiece& str) {
-  const int64 KB = 1024;
-  const int64 MB = 1024 * KB;
-  const int64 GB = 1024 * MB;
-  if (str.size() == 0u)
-    return -1;
-  int64 unit_multiplier = 1;
-  size_t length = str.size();
-  if (str[length - 1] == 'k') {
-    unit_multiplier = KB;
-    length--;
-  } else if (str[length - 1] == 'm') {
-    unit_multiplier = MB;
-    length--;
-  } else if (str[length - 1] == 'g') {
-    unit_multiplier = GB;
-    length--;
-  }
-  int64 result = 0;
-  bool parsed = base::StringToInt64(str.substr(0, length), &result);
-  bool negative = result <= 0;
-  bool overflow = result >= std::numeric_limits<int64>::max() / unit_multiplier;
-  if (!parsed || negative || overflow)
-    return -1;
-  return result * unit_multiplier;
-}
-
 int GetDalvikHeapSizeMB() {
-  char heap_size_str[PROP_VALUE_MAX];
-  __system_property_get("dalvik.vm.heapsize", heap_size_str);
-  // dalvik.vm.heapsize property is writable by a root user.
-  // Clamp it to reasonable range as a sanity check,
-  // a typical android device will never have less than 48MB.
-  const int64 MB = 1024 * 1024;
-  int64 result = ParseSystemPropertyBytes(heap_size_str);
+  // See developer.android.com/reference/android/app/ActivityManager.html for
+  // how "large memory class" relates to the Dalvik heap size.
+  int result = base::android::BuildInfo::GetInstance()->large_memory_class();
   if (result == -1) {
      // We should consider not exposing these values if they are not reliable.
-     LOG(ERROR) << "Can't parse dalvik.vm.heapsize: " << heap_size_str;
+     LOG(ERROR) << "Invalid large memory class: " << result;

[Lei Zhang, 2015/08/05 00:28:24]

nit: outputting |result| isn't helpful. We already know it's -1.

[jdduke (slow), 2015/08/05 15:32:09]

Done.

      result = base::SysInfo::AmountOfPhysicalMemoryMB() / 3;
   }
-  result = std::min<int64>(std::max<int64>(32 * MB, result), 1024 * MB) / MB;
-  return static_cast<int>(result);
-}
-
-int GetDalvikHeapGrowthLimitMB() {
-  char heap_size_str[PROP_VALUE_MAX];
-  __system_property_get("dalvik.vm.heapgrowthlimit", heap_size_str);
-  // dalvik.vm.heapgrowthlimit property is writable by a root user.
-  // Clamp it to reasonable range as a sanity check,
-  // a typical android device will never have less than 24MB.
-  const int64 MB = 1024 * 1024;
-  int64 result = ParseSystemPropertyBytes(heap_size_str);
-  if (result == -1) {
-     // We should consider not exposing these values if they are not reliable.
-     LOG(ERROR) << "Can't parse dalvik.vm.heapgrowthlimit: " << heap_size_str;
-     result = base::SysInfo::AmountOfPhysicalMemoryMB() / 6;
-  }
-  result = std::min<int64>(std::max<int64>(16 * MB, result), 512 * MB) / MB;
-  return static_cast<int>(result);
+  return std::min(std::max(32, result), 1024);
 }
 
 }  // anonymous namespace
@@ -156,9 +62,7 @@ int GetDalvikHeapGrowthLimitMB() {
 namespace base {
 
 std::string SysInfo::HardwareModelName() {
-  char device_model_str[PROP_VALUE_MAX];
-  __system_property_get("ro.product.model", device_model_str);
-  return std::string(device_model_str);
+  return android::BuildInfo::GetInstance()->model();
 }
 
 std::string SysInfo::OperatingSystemName() {
@@ -166,17 +70,14 @@ std::string SysInfo::OperatingSystemName() {
 }
 
 std::string SysInfo::OperatingSystemVersion() {
-  int32 major, minor, bugfix;
-  OperatingSystemVersionNumbers(&major, &minor, &bugfix);
-  return StringPrintf("%d.%d.%d", major, minor, bugfix);
+  return android::BuildInfo::GetInstance()->build_version_release();
 }
 
 void SysInfo::OperatingSystemVersionNumbers(int32* major_version,
                                             int32* minor_version,
                                             int32* bugfix_version) {
-  // Read the version number string out from the properties.
-  char os_version_str[PROP_VALUE_MAX];
-  __system_property_get("ro.build.version.release", os_version_str);
+  const char* os_version_str =
+      android::BuildInfo::GetInstance()->build_version_release();
 
   // Parse out the numbers.
   ParseOSVersionNumbers(os_version_str, major_version, minor_version,
@@ -184,15 +85,11 @@ void SysInfo::OperatingSystemVersionNumbers(int32* major_version,
 }
 
 std::string SysInfo::GetAndroidBuildCodename() {
-  char os_version_codename_str[PROP_VALUE_MAX];
-  __system_property_get("ro.build.version.codename", os_version_codename_str);
-  return std::string(os_version_codename_str);
+  return android::BuildInfo::GetInstance()->build_version_codename();
 }
 
 std::string SysInfo::GetAndroidBuildID() {
-  char os_build_id_str[PROP_VALUE_MAX];
-  __system_property_get("ro.build.id", os_build_id_str);
-  return std::string(os_build_id_str);
+  return android::BuildInfo::GetInstance()->build_id();
 }
 
 int SysInfo::DalvikHeapSizeMB() {
@@ -200,11 +97,6 @@ int SysInfo::DalvikHeapSizeMB() {
   return heap_size;
 }
 
-int SysInfo::DalvikHeapGrowthLimitMB() {
-  static int heap_growth_limit = GetDalvikHeapGrowthLimitMB();
-  return heap_growth_limit;
-}
-
 static base::LazyInstance<
     base::internal::LazySysInfoValue<bool,
         android::SysUtils::IsLowEndDeviceFromJni> >::Leaky