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/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ANDROID_BASE_PROPERTIES_H
#define ANDROID_BASE_PROPERTIES_H
#include <sys/cdefs.h>
#if !defined(__BIONIC__)
#error Only bionic supports system properties.
#endif
#include <limits>
#include <string>
namespace android {
namespace base {
// Returns the current value of the system property `key`,
// or `default_value` if the property is empty or doesn't exist.
std::string GetProperty(const std::string& key, const std::string& default_value);
// Returns true if the system property `key` has the value "1", "y", "yes", "on", or "true",
// false for "0", "n", "no", "off", or "false", or `default_value` otherwise.
bool GetBoolProperty(const std::string& key, bool default_value);
// Returns the signed integer corresponding to the system property `key`.
// If the property is empty, doesn't exist, doesn't have an integer value, or is outside
// the optional bounds, returns `default_value`.
template <typename T> T GetIntProperty(const std::string& key,
T default_value,
T min = std::numeric_limits<T>::min(),
T max = std::numeric_limits<T>::max());
// Returns the unsigned integer corresponding to the system property `key`.
// If the property is empty, doesn't exist, doesn't have an integer value, or is outside
// the optional bound, returns `default_value`.
template <typename T> T GetUintProperty(const std::string& key,
T default_value,
T max = std::numeric_limits<T>::max());
// Sets the system property `key` to `value`.
// Note that system property setting is inherently asynchronous so a return value of `true`
// isn't particularly meaningful, and immediately reading back the value won't necessarily
// tell you whether or not your call succeeded. A `false` return value definitely means failure.
bool SetProperty(const std::string& key, const std::string& value);
} // namespace base
} // namespace android
#endif // ANDROID_BASE_MEMORY_H
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