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//midi for embedded chips,
//Copyright 2010 Alex Norman
//
//This file is part of avr-midi.
//
//avr-midi is free software: you can redistribute it and/or modify
//it under the terms of the GNU General Public License as published by
//the Free Software Foundation, either version 3 of the License, or
//(at your option) any later version.
//
//avr-midi is distributed in the hope that it will be useful,
//but WITHOUT ANY WARRANTY; without even the implied warranty of
//MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
//GNU General Public License for more details.
//
//You should have received a copy of the GNU General Public License
//along with avr-midi. If not, see <http://www.gnu.org/licenses/>.
#ifndef SYSEX_TOOLS_H
#define SYSEX_TOOLS_H
#include <inttypes.h>
/**
* These functions are for converting data to and from a "midi-safe" format,
* which can be use to send data with sysex messages. Sysex messages may only
* contain data where the to bit is not set.
*
* A bit "packed" midi message is one that contains all of the data from its
* original state, but does not have any of the top bits set.
*
* Every 7 bytes of unpacked data is converted into 8 bytes of packed data and
* visa-versa. If you'd like to operate on small segments, make sure that you
* pack in 7 byte increments and unpack in 8 byte increments.
*
*/
/**
* Compute the length of a message after it is packed.
*
* @param unpacked_length The length, in bytes, of the message to pack.
*
* @return The length, in bytes, of the message after packing.
*/
uint16_t sysex_bit_packed_length(uint16_t unpacked_length);
/**
* Compute the length of a message after it is unpacked.
*
* @param packed_length The length, in bytes, of the packed message.
*
* @return The length, in bytes, of the message after it is unpacked.
*/
uint16_t sysex_bit_unpacked_length(uint16_t packed_length);
/**
* Pack data so that it can be transmitted safely in a sysex message.
*
* @param packed The output data buffer, must be at least sysex_bit_packed_length(length) bytes long.
* @param source The input buffer of data to be packed.
* @param length The number of bytes from the input buffer to pack.
*
* @return number of bytes packed.
*/
uint16_t sysex_bit_pack(uint8_t *packed, const uint8_t *source, uint16_t length);
/**
* Unpack packed data.
*
* @param unpacked The output data buffer, must be at least sysex_bit_unpacked_length(length) bytes long.
* @param source The input buffer of data to be unpacked.
* @param length The number of bytes from the input buffer to unpack.
*
* @return number of bytes unpacked.
*/
uint16_t sysex_bit_unpack(uint8_t *unpacked, const uint8_t *source, uint16_t length);
#endif
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