text: /*
   * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
   * 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.
   *
   * 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.
   */
  
  #include <AK/IPv4Address.h>
  #include <AK/Types.h>
  #include <LibCore/CNotifier.h>
  #include <LibCore/CUdpServer.h>
  #include <LibCore/CUdpSocket.h>
  #include <stdio.h>
  #include <sys/socket.h>
  
  namespace Core {
  
  UdpServer::UdpServer(Object* parent)
      : Object(parent)
  {
      m_fd = socket(AF_INET, SOCK_DGRAM | SOCK_NONBLOCK | SOCK_CLOEXEC, 0);
      ASSERT(m_fd >= 0);
  }
  
  UdpServer::~UdpServer()
  {
  }
  
  bool UdpServer::listen(const IPv4Address& address, u16 port)
  {
      if (m_listening)
          return false;
  
      int rc;
      auto socket_address = SocketAddress(address, port);
      auto in = socket_address.to_sockaddr_in();
      rc = ::bind(m_fd, (const sockaddr*)&in, sizeof(in));
      ASSERT(rc == 0);
  
      rc = ::listen(m_fd, 5);
      ASSERT(rc == 0);
      m_listening = true;
  
      m_notifier = Notifier::construct(m_fd, Notifier::Event::Read);
      m_notifier->on_ready_to_read = [this] {
          if (on_ready_to_accept)
              on_ready_to_accept();
      };
      return true;
  }
  
  RefPtr<UdpSocket> UdpServer::accept()
  {
      ASSERT(m_listening);
      sockaddr_in in;
      socklen_t in_size = sizeof(in);
      int accepted_fd = ::accept(m_fd, (sockaddr*)&in, &in_size);
      if (accepted_fd < 0) {
          perror("accept");
          return nullptr;
      }
  
      return UdpSocket::construct(accepted_fd);
  }
  
  Optional<IPv4Address> UdpServer::local_address() const
  {
      if (m_fd == -1)
          return {};
  
      sockaddr_in address;
      socklen_t len = sizeof(address);
      if (getsockname(m_fd, (sockaddr*)&address, &len) != 0)
          return {};
  
      return IPv4Address(address.sin_addr.s_addr);
  }
  
  Optional<u16> UdpServer::local_port() const
  {
      if (m_fd == -1)
          return {};
  
      sockaddr_in address;
      socklen_t len = sizeof(address);
      if (getsockname(m_fd, (sockaddr*)&address, &len) != 0)
          return {};
  
      return ntohs(address.sin_port);
  }
  
  }
  