dot1q.h

/*
 * Copyright (c) 2017, Matias Fontanini
 * 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.
 * 
 * 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 THE COPYRIGHT
 * OWNER OR CONTRIBUTORS 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.
 *
 */
 
#ifndef TINS_DOT1Q_H
#define TINS_DOT1Q_H
 
#include <tins/pdu.h>
#include <tins/macros.h>
#include <tins/endianness.h>
#include <tins/small_uint.h>
 
namespace Tins {

class TINS_API Dot1Q : public PDU {
public:
    static const PDU::PDUType pdu_flag = PDU::DOT1Q;
    
    static metadata extract_metadata(const uint8_t *buffer, uint32_t total_sz);

    Dot1Q(small_uint<12> tag_id = 0, bool append_pad = true);

    Dot1Q(const uint8_t* buffer, uint32_t total_sz);
 
    // Getters

    uint32_t header_size() const;

    uint32_t trailer_size() const;

    small_uint<3> priority() const {
        return header_.priority;
    }

    small_uint<1> cfi() const {
        return header_.cfi;
    }

    small_uint<12> id() const {
        #if TINS_IS_LITTLE_ENDIAN
            return header_.idL | (header_.idH << 8);
        #else
            return header_.id;
        #endif
    }

    uint16_t payload_type() const {
        return Endian::be_to_host(header_.type);
    }

    PDUType pdu_type() const {
        return pdu_flag;
    }
    
    Dot1Q* clone() const {
        return new Dot1Q(*this);
    }

    bool append_padding() const {
        return append_padding_;
    }
 
    // Setters

    void priority(small_uint<3> new_priority);

    void cfi(small_uint<1> new_cfi);

    void id(small_uint<12> new_id);

    void payload_type(uint16_t new_type);
    
    void append_padding(bool value);
    
    bool matches_response(const uint8_t* ptr, uint32_t total_sz) const;
private:
    void write_serialization(uint8_t* buffer, uint32_t total_sz);
 
    TINS_BEGIN_PACK
    struct dot1q_header {
        #if TINS_IS_BIG_ENDIAN
            uint16_t priority:3,
                    cfi:1,
                    id:12;
            uint16_t type;
        #else
            uint16_t idH:4,
                    cfi:1,
                    priority:3,
                    idL:8;
            uint16_t type;
        #endif
    } TINS_END_PACK;
    
    static uint16_t get_id(const dot1q_header* hdr);
    
    dot1q_header header_;
    bool append_padding_;
};
}
 
#endif // TINS_DOT1Q_H