host_settings.h

// Copyright 2021 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef REMOTING_BASE_HOST_SETTINGS_H_
#define REMOTING_BASE_HOST_SETTINGS_H_

#include <string>

namespace remoting {

using HostSettingKey = char[];

// A class to read host settings, which are simple key-value pairs unrelated to
// the host's identity, like UID of an audio device to capture audio from, or
// whether a feature should be enabled.
class HostSettings {
 public:
  // Initializes host settings. Must be called on a thread that allows blocking
  // before calling GetValue().
  static void Initialize();

  static HostSettings* GetInstance();

  // Gets the value associated with |key|. Returns |default_value| if the value
  // is not found.
  virtual std::string GetString(
      const HostSettingKey key,
      const std::string& default_value = std::string()) const = 0;

  // Sets a string value for |key| and writes it into the settings file.
  //
  // NOTE that the current implementation requires the whole instance to be used
  // on the same sequence once SetString() is called.
  virtual void SetString(const HostSettingKey key,
                         const std::string& value) = 0;

  HostSettings(const HostSettings&) = delete;
  HostSettings& operator=(const HostSettings&) = delete;

 protected:
  HostSettings();
  virtual ~HostSettings();

  virtual void InitializeInstance() = 0;
};

}  // namespace remoting

#endif  // REMOTING_BASE_HOST_SETTINGS_H_