android_util.h

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#ifndef MOZC_BASE_ANDROID_UTIL_H_
#define MOZC_BASE_ANDROID_UTIL_H_

#include <jni.h>
#include <map>
#include <set>
#include <string>

#include "testing/friend_test.h"

namespace mozc {

class AndroidUtil {
 public:
  AndroidUtil() = delete;
  AndroidUtil(const AndroidUtil &) = delete;
  AndroidUtil &operator=(const AndroidUtil &) = delete;

  // Frequently used property names.
  static const char kSystemPropertyOsVersion[];
  static const char kSystemPropertyModel[];
  static const char kSystemPropertySdkVersion[];

  // Reads system property from file system.
  // Note that dynamic properties (e.g. ro.build.date)
  // cannot be obtained.
  // If no property is found or something goes wrong,
  // returns |default_value|.
  // Typical usage :
  //   EXPECT_EQ(
  //     AndroidUtil::GetSystemProperty(kAndroidSystemPropertyModel),
  //     "Nexus One");
  // Note : Using ::popen("getprop [property name]", "r") is better solution
  // but currently popen seems to be unstable.
  static std::string GetSystemProperty(const std::string &key,
                                       const std::string &default_value);

 private:
  FRIEND_TEST(AndroidUtilTest, ParseLine_valid);
  FRIEND_TEST(AndroidUtilTest, ParseLine_invalid);

  // Gets the property's value, which is read from file system.
  // If successfully done, the result will be stored in |output| and
  // returns true.
  // If something goes wrong (e.g. file system error, non-existent property
  // name), returns false. |output| is undefined.
  static bool GetPropertyFromFile(const std::string &key, std::string *output);

  // Parses the line.
  // If the returned value is true, the property's key and value string are
  // returned as |lhs| and |rhs| respectively.
  // If false, |line| is malformed.
  // In this case |lhs| and |rhs| are not modified.
  static bool ParseLine(const std::string &line, std::string *lhs,
                        std::string *rhs);

  static std::map<std::string, std::string> property_cache;
  static std::set<std::string> undefined_keys;
};

}  // namespace mozc
#endif  // MOZC_BASE_ANDROID_UTIL_H_