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//
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//
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// Copyright (c) 2023 Vinnie Falco (vinnie.falco@gmail.com)
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// Copyright (c) 2023 Vinnie Falco (vinnie.falco@gmail.com)
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//
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//
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
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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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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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//
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//
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// Official repository: https://github.com/cppalliance/capy
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// Official repository: https://github.com/cppalliance/capy
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//
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//
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#include <boost/capy/buffers/circular_dynamic_buffer.hpp>
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#include <boost/capy/buffers/circular_dynamic_buffer.hpp>
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#include <boost/capy/detail/except.hpp>
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#include <boost/capy/detail/except.hpp>
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namespace boost {
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namespace boost {
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namespace capy {
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namespace capy {
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auto
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auto
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circular_dynamic_buffer::
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circular_dynamic_buffer::
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data() const noexcept ->
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data() const noexcept ->
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    const_buffers_type
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    const_buffers_type
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{
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{
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    if(in_pos_ + in_len_ <= cap_)
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    if(in_pos_ + in_len_ <= cap_)
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        return {{
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        return {{
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            const_buffer{ base_ + in_pos_, in_len_ },
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            const_buffer{ base_ + in_pos_, in_len_ },
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            const_buffer{ base_, 0} }};
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            const_buffer{ base_, 0} }};
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    return {{
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    return {{
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        const_buffer{ base_ + in_pos_, cap_ - in_pos_},
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        const_buffer{ base_ + in_pos_, cap_ - in_pos_},
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        const_buffer{ base_, in_len_- (cap_ - in_pos_)} }};
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        const_buffer{ base_, in_len_- (cap_ - in_pos_)} }};
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}
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}
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auto
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auto
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circular_dynamic_buffer::
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circular_dynamic_buffer::
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prepare(std::size_t n) ->
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prepare(std::size_t n) ->
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    mutable_buffers_type
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    mutable_buffers_type
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{
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{
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    // Buffer is too small for n
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    // Buffer is too small for n
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    if(n > cap_ - in_len_)
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    if(n > cap_ - in_len_)
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        detail::throw_length_error();
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        detail::throw_length_error();
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    out_size_ = n;
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    out_size_ = n;
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    auto const pos = (
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    auto const pos = (
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        in_pos_ + in_len_) % cap_;
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        in_pos_ + in_len_) % cap_;
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    if(pos + n <= cap_)
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    if(pos + n <= cap_)
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        return {{
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        return {{
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            mutable_buffer{ base_ + pos, n },
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            mutable_buffer{ base_ + pos, n },
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            mutable_buffer{ base_, 0 } }};
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            mutable_buffer{ base_, 0 } }};
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    return {{
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    return {{
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        mutable_buffer{ base_ + pos, cap_ - pos },
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        mutable_buffer{ base_ + pos, cap_ - pos },
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        mutable_buffer{ base_, n - (cap_ - pos) } }};
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        mutable_buffer{ base_, n - (cap_ - pos) } }};
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}
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}
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void
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void
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circular_dynamic_buffer::
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circular_dynamic_buffer::
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commit(
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commit(
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    std::size_t n) noexcept
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    std::size_t n) noexcept
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{
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{
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    if(n < out_size_)
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    if(n < out_size_)
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        in_len_ += n;
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        in_len_ += n;
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    else
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    else
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        in_len_ += out_size_;
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        in_len_ += out_size_;
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    out_size_ = 0;
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    out_size_ = 0;
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}
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}
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void
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void
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circular_dynamic_buffer::
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circular_dynamic_buffer::
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consume(
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consume(
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    std::size_t n) noexcept
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    std::size_t n) noexcept
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{
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{
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    if(n < in_len_)
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    if(n < in_len_)
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    {
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    {
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        in_pos_ = (in_pos_ + n) % cap_;
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        in_pos_ = (in_pos_ + n) % cap_;
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        in_len_ -= n;
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        in_len_ -= n;
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    }
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    }
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    else
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    else
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    {
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    {
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        // preserve in_pos_ if there is
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        // preserve in_pos_ if there is
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        // a prepared buffer
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        // a prepared buffer
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        if(out_size_ != 0)
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        if(out_size_ != 0)
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        {
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        {
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            in_pos_ = (in_pos_ + in_len_) % cap_;
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            in_pos_ = (in_pos_ + in_len_) % cap_;
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            in_len_ = 0;
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            in_len_ = 0;
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        }
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        }
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        else
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        else
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        {
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        {
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            // make prepare return a
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            // make prepare return a
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            // bigger single buffer
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            // bigger single buffer
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            in_pos_ = 0;
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            in_pos_ = 0;
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            in_len_ = 0;
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            in_len_ = 0;
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        }
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        }
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    }
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    }
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}
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}
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} // capy
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} // capy
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} // boost
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} // boost