text: // Copyright (c) 2014-2020, The LibertyChain Project
  // 
  // All rights reserved.
  // 
  // Redistribution and use in source and binary forms, with or without modification, are
  // permitted provided that the following conditions are met:
  // 
  // 1. Redistributions of source code must retain the above copyright notice, this list of
  //    conditions and the following disclaimer.
  // 
  // 2. 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.
  // 
  // 3. Neither the name of the copyright holder 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 HOLDER 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.
  // 
  // Parts of this file are originally copyright (c) 2012-2013 The Cryptonote developers
  
  #pragma once
  
  #include <string>
  #include <atomic>
  #include <boost/optional/optional.hpp>
  #include "wipeable_string.h"
  
  namespace tools
  {
    class password_container
    {
    public:
      static constexpr const size_t max_password_size = 1024;
  
      //! Empty password
      password_container() noexcept;
  
      //! `password` is used as password
      password_container(std::string&& password) noexcept;
      password_container(const epee::wipeable_string& password) noexcept;
  
      //! \return A password from stdin TTY prompt or `std::cin` pipe.
      static boost::optional<password_container> prompt(bool verify, const char *mesage = "Password", bool hide_input = true);
      static std::atomic<bool> is_prompting;
  
      password_container(const password_container&) = delete;
      password_container(password_container&& rhs) = default;
  
      //! Wipes internal password
      ~password_container() noexcept;
  
      password_container& operator=(const password_container&) = delete;
      password_container& operator=(password_container&&) = default;
  
      const epee::wipeable_string &password() const noexcept { return m_password; }
  
    private:
      epee::wipeable_string m_password;
    };
  
    struct login
    {
      login() = default;
  
      /*!
         Extracts username and password from the format `username:password`. A
         blank username or password is allowed. If the `:` character is not
         present, `password_container::prompt` will be called by forwarding the
         `verify` and `message` arguments.
  
         \param userpass Is "consumed", and the memory contents are wiped.
         \param verify is passed to `password_container::prompt` if necessary.
         \param message is passed to `password_container::prompt` if necessary.
  
         \return The username and password, or boost::none if
           `password_container::prompt` fails.
       */
      static boost::optional<login> parse(std::string&& userpass, bool verify, const std::function<boost::optional<password_container>(bool)> &prompt);
  
      login(const login&) = delete;
      login(login&&) = default;
      ~login() = default;
      login& operator=(const login&) = delete;
      login& operator=(login&&) = default;
  
      std::string username;
      password_container password;
    };
  }
  