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//
 
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// Copyright (c) 2026 Michael Vandeberg
 
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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_FILE_BASE_HPP
 
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#define BOOST_COROSIO_FILE_BASE_HPP
 
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#include <boost/corosio/detail/config.hpp>
 
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namespace boost::corosio {
 
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/** Common definitions for file I/O objects.
 
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    Provides open flags and seek origin constants shared
 
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    by @ref stream_file and @ref random_access_file.
 
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*/
 
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struct file_base
 
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{
 
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    /** Bitmask flags for opening a file.
 
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        Flags are combined with bitwise OR to specify the
 
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        desired access mode and creation behavior.
 
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    */
 
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    enum flags : unsigned
 
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    {
 
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        /// Open for reading only.
 
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        read_only = 1,
 
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        /// Open for writing only.
 
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        write_only = 2,
 
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        /// Open for reading and writing.
 
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        read_write = read_only | write_only,
 
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        /// Append to the end of the file on each write.
 
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        append = 4,
 
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        /// Create the file if it does not exist.
 
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        create = 8,
 
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        /// Fail if the file already exists (requires @ref create).
 
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        exclusive = 16,
 
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        /// Truncate the file to zero length on open.
 
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        truncate = 32,
 
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        /// Synchronize data to disk on each write.
 
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        sync_all_on_write = 64
 
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    };
 
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    /** Origin for seek operations. */
 
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    enum seek_basis
 
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    {
 
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        /// Seek relative to the beginning of the file.
 
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        seek_set,
 
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        /// Seek relative to the current position.
 
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        seek_cur,
 
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        /// Seek relative to the end of the file.
 
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        seek_end
 
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    };
 
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    friend constexpr flags operator|(flags a, flags b) noexcept
 
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    {
 
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        return static_cast<flags>(
 
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            static_cast<unsigned>(a) | static_cast<unsigned>(b));
 
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    }
 
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    friend constexpr flags operator&(flags a, flags b) noexcept
 
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    {
 
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        return static_cast<flags>(
 
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            static_cast<unsigned>(a) & static_cast<unsigned>(b));
 
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    }
 
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    friend constexpr flags& operator|=(flags& a, flags b) noexcept
 
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    {
 
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        return a = a | b;
 
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    }
 
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    friend constexpr flags& operator&=(flags& a, flags b) noexcept
 
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    {
 
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        return a = a & b;
 
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    }
 
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};
 
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} // namespace boost::corosio
 
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#endif // BOOST_COROSIO_FILE_BASE_HPP