packet_header.h

Go to the documentation of this file.

/*
 * Copyright (c) 2009 Lukas Mejdrech
 * 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.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 LIBC_PACKET_HEADER_H_
#define LIBC_PACKET_HEADER_H_

#include <net/packet.h>

#define PACKET_DATA_LENGTH(header) \
        ((header)->data_end - (header)->data_start)

#define PACKET_MAX_ADDRESS_LENGTH(header) \
        ((header)->dest_addr - (header)->src_addr)

#define PACKET_MIN_SUFFIX(header) \
        ((header)->length - (header)->data_start - (header)->max_content)

#define PACKET_MAGIC_VALUE      0x11227788

struct packet {
        packet_id_t packet_id;

        size_t order;

        size_t metric;
        packet_id_t previous;
        packet_id_t next;

        size_t length;

        size_t addr_len;

        size_t src_addr;

        size_t dest_addr;

        size_t max_prefix;
        size_t max_content;

        size_t data_start;

        size_t data_end;

        int magic_value;
};

static inline int packet_is_valid(const packet_t *packet)
{
        return packet && (packet->magic_value == PACKET_MAGIC_VALUE);
}

#endif

---