osd-contiki/core/net/mac/framer.h
Niclas Finne 68730566a3 Added method to framer that returns the header length if the framer
would create a header with the current packet information.

This allows sicslowpan to calculate the max payload size without
consuming a sequence number or clearing/restoring the packet buffer.
2014-04-11 17:03:23 +02:00

55 lines
2 KiB
C

/*
* Copyright (c) 2009, Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. Neither the name of the Institute 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 INSTITUTE 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 INSTITUTE 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.
*
*/
/**
* \file
* A MAC framer is responsible for constructing and parsing
* the header in MAC frames. At least the sender and receiver
* are required to be encoded in the MAC frame headers.
* \author
* Niclas Finne <nfi@sics.se>
* Joakim Eriksson <joakime@sics.se>
*/
#ifndef FRAMER_H_
#define FRAMER_H_
#define FRAMER_FAILED -1
struct framer {
int (* length)(void);
int (* create)(void);
int (* parse)(void);
};
#endif /* FRAMER_H_ */