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//
 
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// Copyright (c) 2026 Steve Gerbino
 
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//
 
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
 
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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
 
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//
 
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// Official repository: https://github.com/cppalliance/corosio
 
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//
 
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#ifndef BOOST_COROSIO_UDP_HPP
 
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#define BOOST_COROSIO_UDP_HPP
 
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#include <boost/corosio/detail/config.hpp>
 
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namespace boost::corosio {
 
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class udp_socket;
 
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/** Encapsulate the UDP protocol for socket creation.
 
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    This class identifies the UDP protocol and its address family
 
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    (IPv4 or IPv6). It is used to parameterize `udp_socket::open()`
 
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    calls with a self-documenting type.
 
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    The `family()`, `type()`, and `protocol()` members are
 
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    implemented in the compiled library to avoid exposing
 
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    platform socket headers. For an inline variant that includes
 
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    platform headers, use @ref native_udp.
 
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    @par Example
 
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    @code
 
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    udp_socket sock( ioc );
 
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    sock.open( udp::v4() );
 
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    sock.bind( endpoint( ipv4_address::any(), 9000 ) );
 
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    @endcode
 
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    @see native_udp, udp_socket
 
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*/
 
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class BOOST_COROSIO_DECL udp
 
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{
 
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    bool v6_;
 
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    explicit constexpr udp(bool v6) noexcept : v6_(v6) {}
 
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public:
 
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    /// Construct an IPv4 UDP protocol.
 
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    static constexpr udp v4() noexcept
 
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    {
 
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        return udp(false);
 
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    }
 
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    /// Construct an IPv6 UDP protocol.
 
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    static constexpr udp v6() noexcept
 
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    {
 
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        return udp(true);
 
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    }
 
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    /// Return true if this is IPv6.
 
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    constexpr bool is_v6() const noexcept
 
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    {
 
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        return v6_;
 
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    }
 
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    /// Return the address family (AF_INET or AF_INET6).
 
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    int family() const noexcept;
 
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    /// Return the socket type (SOCK_DGRAM).
 
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    static int type() noexcept;
 
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    /// Return the IP protocol (IPPROTO_UDP).
 
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    static int protocol() noexcept;
 
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    /// The associated socket type.
 
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    using socket = udp_socket;
 
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    /// Test for equality.
 
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    friend constexpr bool operator==(udp a, udp b) noexcept
 
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    {
 
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        return a.v6_ == b.v6_;
 
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    }
 
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    /// Test for inequality.
 
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    friend constexpr bool operator!=(udp a, udp b) noexcept
 
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    {
 
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        return a.v6_ != b.v6_;
 
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    }
 
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};
 
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} // namespace boost::corosio
 
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#endif // BOOST_COROSIO_UDP_HPP