| Line | Branch | Exec | Source |
|---|---|---|---|
| 1 | // | ||
| 2 | // Copyright (c) 2021 Vinnie Falco (vinnie.falco@gmail.com) | ||
| 3 | // Copyright (c) 2024 Christian Mazakas | ||
| 4 | // Copyright (c) 2024 Mohammad Nejati | ||
| 5 | // | ||
| 6 | // Distributed under the Boost Software License, Version 1.0. (See accompanying | ||
| 7 | // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) | ||
| 8 | // | ||
| 9 | // Official repository: https://github.com/cppalliance/http_proto | ||
| 10 | // | ||
| 11 | |||
| 12 | #ifndef BOOST_HTTP_PROTO_SERVICE_ZLIB_SERVICE_HPP | ||
| 13 | #define BOOST_HTTP_PROTO_SERVICE_ZLIB_SERVICE_HPP | ||
| 14 | |||
| 15 | #include <boost/http_proto/context.hpp> | ||
| 16 | #include <boost/http_proto/detail/config.hpp> | ||
| 17 | #include <boost/http_proto/detail/workspace.hpp> | ||
| 18 | #include <boost/http_proto/service/service.hpp> | ||
| 19 | |||
| 20 | namespace boost { | ||
| 21 | namespace http_proto { | ||
| 22 | namespace zlib { | ||
| 23 | |||
| 24 | struct decoder_config | ||
| 25 | { | ||
| 26 | unsigned max_window_bits = 15; | ||
| 27 | unsigned mem_level = 8; | ||
| 28 | }; | ||
| 29 | |||
| 30 | constexpr | ||
| 31 | inline | ||
| 32 | std::size_t | ||
| 33 | 24 | encoding_size_hint(decoder_config cfg = {}) noexcept | |
| 34 | { | ||
| 35 | // from: https://www.zlib.net/zlib_tech.html | ||
| 36 | // | ||
| 37 | // Memory Footprint | ||
| 38 | // | ||
| 39 | // zlib's memory footprint can also be specified fairly | ||
| 40 | // precisely. It is larger for compression than for | ||
| 41 | // decompression, and the exact requirements depend on | ||
| 42 | // how the library was compiled. | ||
| 43 | // | ||
| 44 | // The memory requirements for compression depend on two | ||
| 45 | // parameters, windowBits and memLevel: | ||
| 46 | // deflate memory usage (bytes) = (1 << (windowBits+2)) + (1 << (memLevel+9)) + 6 KB | ||
| 47 | return | ||
| 48 | 24 | (1 << (cfg.max_window_bits + 2)) + | |
| 49 | 24 | (1 << (cfg.mem_level + 9)) + | |
| 50 | 24 | (6 * 1024); | |
| 51 | } | ||
| 52 | |||
| 53 | /** Error codes returned from compression/decompression functions. | ||
| 54 | |||
| 55 | Negative values are errors, positive values are used | ||
| 56 | for special but normal events. | ||
| 57 | */ | ||
| 58 | enum class error | ||
| 59 | { | ||
| 60 | ok = 0, | ||
| 61 | stream_end = 1, | ||
| 62 | need_dict = 2, | ||
| 63 | errno_ = -1, | ||
| 64 | stream_err = -2, | ||
| 65 | data_err = -3, | ||
| 66 | mem_err = -4, | ||
| 67 | buf_err = -5, | ||
| 68 | version_err = -6 | ||
| 69 | }; | ||
| 70 | |||
| 71 | /// Flush methods. | ||
| 72 | enum class flush | ||
| 73 | { | ||
| 74 | none, | ||
| 75 | partial, | ||
| 76 | sync, | ||
| 77 | full, | ||
| 78 | finish, | ||
| 79 | block, | ||
| 80 | trees | ||
| 81 | }; | ||
| 82 | |||
| 83 | /** Input and output buffers. | ||
| 84 | |||
| 85 | The application must update `next_in` and `avail_in` when `avail_in` | ||
| 86 | has dropped to zero. It must update `next_out` and `avail_out` when | ||
| 87 | `avail_out` has dropped to zero. | ||
| 88 | */ | ||
| 89 | struct params | ||
| 90 | { | ||
| 91 | /// Next input byte | ||
| 92 | void const* next_in; | ||
| 93 | |||
| 94 | /// Number of bytes available at `next_in` | ||
| 95 | std::size_t avail_in; | ||
| 96 | |||
| 97 | /// Next output byte | ||
| 98 | void* next_out; | ||
| 99 | |||
| 100 | /// Number of bytes remaining free at `next_out` | ||
| 101 | std::size_t avail_out; | ||
| 102 | }; | ||
| 103 | |||
| 104 | /// Abstract interface for deflator/inflator streams. | ||
| 105 | struct stream | ||
| 106 | { | ||
| 107 | /** Call the underling compression/decompression algorithm. | ||
| 108 | |||
| 109 | @param p The input and output buffers. | ||
| 110 | |||
| 111 | @param f The flush method. | ||
| 112 | |||
| 113 | @return The result of operation that contains a value | ||
| 114 | of @ref error. | ||
| 115 | */ | ||
| 116 | virtual system::error_code | ||
| 117 | write(params& p, flush f) noexcept = 0; | ||
| 118 | }; | ||
| 119 | |||
| 120 | /** Provides in-memory compression and decompression functions | ||
| 121 | using zlib underneath. | ||
| 122 | */ | ||
| 123 | struct BOOST_HTTP_PROTO_DECL | ||
| 124 | service | ||
| 125 | : http_proto::service | ||
| 126 | { | ||
| 127 | virtual | ||
| 128 | std::size_t | ||
| 129 | space_needed() const noexcept = 0; | ||
| 130 | |||
| 131 | /** Create a deflator stream by calling zlib `deflateInit2()`. | ||
| 132 | |||
| 133 | @param ws A reference to the workspace used for constructing the | ||
| 134 | deflator stream object and for storage used by zlib. | ||
| 135 | |||
| 136 | @param level The compression level. | ||
| 137 | |||
| 138 | @param window_bits The window size. | ||
| 139 | |||
| 140 | @param mem_level Specifies how much memory should be allocated | ||
| 141 | for the internal compression state. | ||
| 142 | |||
| 143 | @return A reference to the created deflator stream. | ||
| 144 | |||
| 145 | @throws std::length_error If there is insufficient free space in | ||
| 146 | @ref `http_proto::detail::workspace`. | ||
| 147 | */ | ||
| 148 | virtual stream& | ||
| 149 | make_deflator( | ||
| 150 | http_proto::detail::workspace& ws, | ||
| 151 | int level, | ||
| 152 | int window_bits, | ||
| 153 | int mem_level) const = 0; | ||
| 154 | |||
| 155 | /** Create an inflator stream by calling zlib `inflateInit2()`. | ||
| 156 | |||
| 157 | @param ws A reference to the workspace used for constructing the | ||
| 158 | inflator stream object and for storage used by zlib. | ||
| 159 | |||
| 160 | @param window_bits The window size. | ||
| 161 | |||
| 162 | @return A reference to the created inflator stream. | ||
| 163 | |||
| 164 | @throws std::length_error If there is insufficient free space in | ||
| 165 | @ref `http_proto::detail::workspace`. | ||
| 166 | */ | ||
| 167 | virtual stream& | ||
| 168 | make_inflator( | ||
| 169 | http_proto::detail::workspace& ws, | ||
| 170 | int window_bits) const = 0; | ||
| 171 | }; | ||
| 172 | |||
| 173 | /** Installs a zlib service on the provided context. | ||
| 174 | |||
| 175 | @param ctx A reference to the @ref context where the service | ||
| 176 | will be installed. | ||
| 177 | |||
| 178 | @throw std::invalid_argument If the zlib service already | ||
| 179 | exist on the context. | ||
| 180 | */ | ||
| 181 | BOOST_HTTP_PROTO_ZLIB_DECL | ||
| 182 | void | ||
| 183 | install_service(context& ctx); | ||
| 184 | |||
| 185 | } // zlib | ||
| 186 | } // http_proto | ||
| 187 | } // boost | ||
| 188 | |||
| 189 | #include <boost/http_proto/service/impl/zlib_service.hpp> | ||
| 190 | |||
| 191 | #endif | ||
| 192 |