text: // Copyright 2010-2016, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  #ifndef MOZC_BASE_PASSWORD_MANAGER_H_
  #define MOZC_BASE_PASSWORD_MANAGER_H_
  
  #include <string>
  
  #include "base/port.h"
  
  namespace mozc {
  
  extern bool kUseMockPasswordManager;
  class PasswordManagerInterface;
  
  // PasswordManager is a class for managing
  // a password(passphrase) used for user-data encryption.
  // It doesn't save user password, but save a session
  // password automatically generated by mozc.
  // PasswordManager uses an OS-provided mechanism
  // to safely save password/passphrase into local disk.
  //
  // Currently, Linux password manager just stores password in plain text.
  // you might want to write your own password manager.
  // See password_manager.cc file for the details.
  
  class PasswordManager {
   public:
    // Initialize password.
    // If password is not found, make a random password internally.
    // return false if initialization failed.
    // Do nothing and return true if password is found.
    static bool InitPassword();
  
    // get current password
    // Call InitPassword() if need be
    static bool GetPassword(string *password);
  
    // remove current password
    static bool RemovePassword();
  
    // set internal interface for unittesting
    static void SetPasswordManagerHandler(
        PasswordManagerInterface *handler);
  
   private:
    DISALLOW_IMPLICIT_CONSTRUCTORS(PasswordManager);
  };
  
  // Implements PasswordManager implementation.
  class PasswordManagerInterface {
   public:
    virtual bool SetPassword(const string &password) const = 0;
    virtual bool GetPassword(string *password) const = 0;
    virtual bool RemovePassword() const = 0;
  
    PasswordManagerInterface() {}
    virtual ~PasswordManagerInterface() {}
  };
  }  // namespace mozc
  
  #endif  // MOZC_BASE_PASSWORD_MANAGER_H_
  