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#pragma once
/* bit vector utility routines */
/* (C) 2009 by Harald Welte <laforge@gnumonks.org>
* (C) 2012 Ivan Klyuchnikov
*
* All Rights Reserved
*
* This program 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 2 of the License, or
* (at your option) any later version.
*
* This program 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 this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
/*! \defgroup bitvec Bit vectors
* @{
*/
/*! \file bitvec.h
* \brief Osmocom bit vector abstraction
*
* These functions assume a MSB (most significant bit) first layout of the
* bits, so that for instance the 5 bit number abcde (a is MSB) can be
* embedded into a byte sequence like in xxxxxxab cdexxxxx. The bit count
* starts with the MSB, so the bits in a byte are numbered (MSB) 01234567 (LSB).
* Note that there are other incompatible encodings, like it is used
* for the EGPRS RLC data block headers (there the bits are numbered from LSB
* to MSB).
*/
#include <stdint.h>
#include <talloc.h>
/*! \brief A single GSM bit
*
* In GSM mac blocks, every bit can be 0 or 1, or L or H. L/H are
* defined relative to the 0x2b padding pattern */
enum bit_value {
ZERO = 0, /*!< \brief A zero (0) bit */
ONE = 1, /*!< \brief A one (1) bit */
L = 2, /*!< \brief A CSN.1 "L" bit */
H = 3, /*!< \brief A CSN.1 "H" bit */
};
/*! \brief structure describing a bit vector */
struct bitvec {
unsigned int cur_bit; /*!< \brief cursor to the next unused bit */
unsigned int data_len; /*!< \brief length of data array in bytes */
uint8_t *data; /*!< \brief pointer to data array */
};
enum bit_value bitvec_get_bit_pos(const struct bitvec *bv, unsigned int bitnr);
enum bit_value bitvec_get_bit_pos_high(const struct bitvec *bv,
unsigned int bitnr);
unsigned int bitvec_get_nth_set_bit(const struct bitvec *bv, unsigned int n);
int bitvec_set_bit_pos(struct bitvec *bv, unsigned int bitnum,
enum bit_value bit);
int bitvec_set_bit(struct bitvec *bv, enum bit_value bit);
int bitvec_get_bit_high(struct bitvec *bv);
int bitvec_set_bits(struct bitvec *bv, enum bit_value *bits, unsigned int count);
int bitvec_set_uint(struct bitvec *bv, uint32_t in, unsigned int count);
int bitvec_get_uint(struct bitvec *bv, unsigned int num_bits);
int bitvec_find_bit_pos(const struct bitvec *bv, unsigned int n, enum bit_value val);
int bitvec_spare_padding(struct bitvec *bv, unsigned int up_to_bit);
int bitvec_get_bytes(struct bitvec *bv, uint8_t *bytes, unsigned int count);
int bitvec_set_bytes(struct bitvec *bv, const uint8_t *bytes, unsigned int count);
struct bitvec *bitvec_alloc(unsigned int size, TALLOC_CTX *bvctx);
void bitvec_free(struct bitvec *bv);
int bitvec_unhex(struct bitvec *bv, const char *src);
unsigned int bitvec_pack(const struct bitvec *bv, uint8_t *buffer);
unsigned int bitvec_unpack(struct bitvec *bv, const uint8_t *buffer);
uint64_t bitvec_read_field(struct bitvec *bv, unsigned int read_index, unsigned int len);
int bitvec_write_field(struct bitvec *bv, unsigned int write_index, uint64_t val, unsigned int len);
/*! @} */
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