Line data    Source code

       1              : //
       2              : // Copyright (c) 2023 Vinnie Falco (vinnie.falco@gmail.com)
       3              : //
       4              : // Distributed under the Boost Software License, Version 1.0. (See accompanying
       5              : // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
       6              : //
       7              : // Official repository: https://github.com/cppalliance/buffers
       8              : //
       9              : 
      10              : #ifndef BOOST_HTTP_PROTO_DETAIL_FILTER_HPP
      11              : #define BOOST_HTTP_PROTO_DETAIL_FILTER_HPP
      12              : 
      13              : #include <boost/http_proto/detail/config.hpp>
      14              : #include <boost/buffers/const_buffer.hpp>
      15              : #include <boost/buffers/const_buffer_span.hpp>
      16              : #include <boost/buffers/mutable_buffer_span.hpp>
      17              : #include <boost/buffers/type_traits.hpp>
      18              : #include <boost/system/error_code.hpp>
      19              : #include <cstddef>
      20              : 
      21              : namespace boost {
      22              : namespace http_proto {
      23              : namespace detail {
      24              : 
      25              : /** A filter for buffers
      26              : */
      27              : class BOOST_HTTP_PROTO_DECL
      28              :     filter
      29              : {
      30              :     template<
      31              :         class T,
      32              :         std::size_t N>
      33              :     class unrolled;
      34              : 
      35              : public:
      36              :     /** The results of processing the filter.
      37              :     */
      38              :     struct results
      39              :     {
      40              :         /** The number of bytes produced in the output.
      41              : 
      42              :             This may be less than the total number
      43              :             of bytes available for writing in the
      44              :             destination buffers.
      45              :         */
      46              :         std::size_t out_bytes = 0;
      47              : 
      48              :         /** The number of bytes consumed from the input.
      49              : 
      50              :             This may be less than the total number
      51              :             of bytes available for reading in the
      52              :             source buffers.
      53              :         */
      54              :         std::size_t in_bytes = 0;
      55              : 
      56              :         /** The error, if any occurred.
      57              :         */
      58              :         system::error_code ec;
      59              : 
      60              :         /** True if there will be no more output.
      61              :         */
      62              :         bool finished = false;
      63              :     };
      64              : 
      65              :     /** Called to process the filter.
      66              : 
      67              :         @par Preconditions
      68              :         @ref init was called once before any
      69              :             calls to `process`.
      70              :     */
      71              :     template<
      72              :         class MutableBufferSequence,
      73              :         class ConstBufferSequence>
      74              :     results
      75        23756 :     process(
      76              :         MutableBufferSequence const& out,
      77              :         ConstBufferSequence const& in,
      78              :         bool more)
      79              :     {
      80              :         static_assert(
      81              :             buffers::is_mutable_buffer_sequence<
      82              :                 MutableBufferSequence>::value,
      83              :             "Type requirements not met");
      84              : 
      85              :         static_assert(
      86              :             buffers::is_const_buffer_sequence<
      87              :                 ConstBufferSequence>::value,
      88              :             "Type requirements not met");
      89              : 
      90        23756 :         return process_impl(out, in, more);
      91              :     }
      92              : 
      93              : #ifdef BOOST_BUFFERS_DOCS
      94              : protected:
      95              : #else
      96              : private:
      97              : #endif
      98              :     /** Derived class override.
      99              : 
     100              :         @par Preconditions
     101              :         @ref init was called once before any
     102              :             calls to `process`
     103              :     */
     104              :     virtual
     105              :     results
     106              :     on_process(
     107              :         buffers::mutable_buffer out,
     108              :         buffers::const_buffer in,
     109              :         bool more) = 0;
     110              : 
     111              :     /** Called to process the filter.
     112              : 
     113              :         @par Preconditions
     114              :         @ref init was called once before any
     115              :             calls to `process`.
     116              :     */
     117              :     virtual
     118              :     results
     119              :     on_process(
     120              :         buffers::mutable_buffer_span out,
     121              :         buffers::const_buffer_span in,
     122              :         bool more);
     123              : 
     124              : private:
     125              :     results
     126        23756 :     process_impl(
     127              :         buffers::mutable_buffer const& out,
     128              :         buffers::const_buffer const& in,
     129              :         bool more)
     130              :     {
     131        23756 :         return on_process(out, in, more);
     132              :     }
     133              : 
     134              :     results
     135              :     process_impl(
     136              :         buffers::mutable_buffer_span const& out,
     137              :         buffers::const_buffer_span const& in,
     138              :         bool more)
     139              :     {
     140              :         return on_process(out, in, more);
     141              :     }
     142              : 
     143              :     template<
     144              :         class MutableBuffers,
     145              :         class ConstBuffers>
     146              :     results
     147              :     process_impl(
     148              :         MutableBuffers const& out,
     149              :         ConstBuffers const& in,
     150              :         bool more);
     151              : };
     152              : 
     153              : } // detail
     154              : } // http_proto
     155              : } // boost
     156              : 
     157              : #include "impl/filter.hpp"
     158              : 
     159              : #endif