qpack.h

/*******************************************************************************
 * Copyright (c) 2014, Jan Koester jan.koester@gmx.net
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 * Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 * Neither the name of the <organization> nor the
 *      names of its contributors may be used to endorse or promote products
 *      derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *******************************************************************************/
 
#pragma once
 
#include <cstddef>
#include <cstdint>
#include <string>
#include <vector>
 
namespace libhttppp::qpack {
 
struct HeaderField {
    std::string name;
    std::string value;
    bool incremental_index = false;
};
 
class Encoder {
public:
    static std::vector<uint8_t> encodeResponseHeaders(uint16_t status_code,
                                                      const std::string &content_type,
                                                      size_t content_length,
                                                      const std::vector<HeaderField> &extra = {});
 
private:
    static void encodeInt(std::vector<uint8_t> &out, uint8_t prefix_byte,
                          uint8_t prefix_bits, uint64_t value);
    static void encodeString(std::vector<uint8_t> &out, const std::string &s);
    static void encodeIndexedStatic(std::vector<uint8_t> &out, uint64_t index);
    static void encodeLiteralStaticNameRef(std::vector<uint8_t> &out,
                                           uint64_t name_index,
                                           const std::string &value);
    static void encodeLiteralName(std::vector<uint8_t> &out,
                                  const std::string &name,
                                  const std::string &value);
};
 
class Decoder {
public:
    static std::vector<HeaderField> decode(const uint8_t *data, size_t len);
private:
    struct StaticEntry { const char *name; const char *value; };
    static const StaticEntry STATIC_TABLE[];
    static const size_t STATIC_TABLE_SIZE;
};
 
} // namespace libhttppp::qpack