OpenModem/bertos/struct/bitarray.h

270 lines
6.5 KiB
C

/**
* \file
* <!--
* This file is part of BeRTOS.
*
* Bertos 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 St, Fifth Floor, Boston, MA 02110-1301 USA
*
* As a special exception, you may use this file as part of a free software
* library without restriction. Specifically, if other files instantiate
* templates or use macros or inline functions from this file, or you compile
* this file and link it with other files to produce an executable, this
* file does not by itself cause the resulting executable to be covered by
* the GNU General Public License. This exception does not however
* invalidate any other reasons why the executable file might be covered by
* the GNU General Public License.
*
* Copyright 2010 Develer S.r.l. (http://www.develer.com/)
* -->
*
* \brief Bitarray module
*
* \author Daniele Basile <asterix@develer.com>
*
* $WIZ$ module_name = "bitarray"
*/
#ifndef STRUCT_BITARRAY_H
#define STRUCT_BITARRAY_H
#include <cfg/compiler.h>
#include <cfg/macros.h>
#include <cfg/debug.h>
#include <cpu/types.h>
typedef struct BitArray
{
size_t size; /// Size in bytes of the bitarray
size_t bitarray_len; /// Number of bits used
uint8_t *array; /// Pointer to memory occupied by the bitarray
} BitArray;
/**
* Convenience macro to create a memory area for the BitArray.
* \param name Name of the variable.
* \param size Number of bits requested. It will be rounded to the nearest
* byte
*/
#define BITARRAY_ALLOC(name, size) uint8_t name[DIV_ROUNDUP((size), 8)]
/**
* Set one bit into the bit array.
* \param bitx BitArray context
* \param idx The bit to set
*/
INLINE void bitarray_set(BitArray *bitx, int idx)
{
ASSERT((size_t)idx <= bitx->bitarray_len);
int page = idx / 8;
uint8_t bit = idx % 8;
bitx->array[page] |= BV(bit);
}
/**
* Clear one bit in the bit array.
* \param bitx BitArray context
* \param idx The bit to clear
*/
INLINE void bitarray_clear(BitArray *bitx, int idx)
{
ASSERT((size_t)idx <= bitx->bitarray_len);
int page = idx / 8;
uint8_t bit = idx % 8;
bitx->array[page] &= ~BV(bit);
}
/**
* Set a range of bits.
*
* The range starts from \a idx (inclusive) and spans \a offset bits.
*
* \param bitx BitArray context
* \param idx Starting bit
* \param offset Number of bit to set
*/
INLINE void bitarray_setRange(BitArray *bitx, int idx, int offset)
{
ASSERT((size_t)idx <= bitx->bitarray_len);
for (int i = idx; i < offset + idx; i++)
bitarray_set(bitx, i);
}
/**
* Clear a range of bits.
*
* The range starts from \a idx (inclusive) and spans \a offset bits.
*
* \param bitx BitArray context
* \param idx Starting bit
* \param offset Number of bits to clear
*/
INLINE void bitarray_clearRange(BitArray *bitx, int idx, int offset)
{
ASSERT((size_t)idx <= bitx->bitarray_len);
for (int i = idx; i < offset + idx; i++)
bitarray_clear(bitx, i);
}
/**
* Test a bit.
*
* \param bitx BitArray context
* \param idx Bit to test
* \return True if bit is set, false otherwise.
*/
INLINE bool bitarray_test(BitArray *bitx, int idx)
{
ASSERT((size_t)idx <= bitx->bitarray_len);
int page = idx / 8;
uint8_t bit = idx % 8;
return (bitx->array[page] & BV(bit));
}
/**
* Check if the bitarray is full
*
* Only \a bitarray_len bits are tested.
*
* \param bitx BitArray to test
* \return True if \a bitx is full, false otherwise
*/
INLINE bool bitarray_isFull(BitArray *bitx)
{
// test full bytes except the last one
for (size_t page = 0; page <= bitx->size - 2; page++)
{
if (!(bitx->array[page] == 0xff))
return 0;
}
// test the last byte using the correct bitmask
uint8_t mask = BV(bitx->bitarray_len >> 3) - 1;
if (!(bitx->array[bitx->size - 1] & mask))
return 0;
return 1;
}
/*
* Ugly!.. reformat it.
*/
/**
* Test if a range of bit is full.
*
* \param bitx BitArray context
* \param idx Starting bit
* \param offset Number of bits to test
* \return True if range is full, false otherwise
*/
INLINE bool bitarray_isRangeFull(BitArray *bitx, int idx, int offset)
{
ASSERT((size_t)(idx + offset) <= bitx->bitarray_len);
for (int i = idx; i <= idx + offset; i++)
if (!bitarray_test(bitx, i))
return 0;
return 1;
}
/*
* Ugly!.. reformat it.
*/
/**
* Test if a range of bit is empty.
*
* \param bitx BitArray context
* \param idx Starting bit
* \param offset Number of bits to test
* \return True if range is empty, false otherwise
*/
INLINE bool bitarray_isRangeEmpty(BitArray *bitx, int idx, int offset)
{
ASSERT((size_t)(idx + offset) <= bitx->bitarray_len);
for (int i = idx; i <= idx + offset; i++)
if (bitarray_test(bitx, i))
return 0;
return 1;
}
/**
* Print on debug serial a BitArray.
* \note This module does not use the logging module, so you
* can't decide the logging level.
* \param bitx BitArray to be printed.
*/
INLINE void bitarray_dump(BitArray *bitx)
{
kprintf("bitarray size[%zu]bits on [%zu]bytes\n", bitx->bitarray_len, bitx->size);
int i = 0;
int j = 0;
int count = bitx->bitarray_len;
while (count--)
{
kprintf("%d", bitarray_test(bitx, i++));
if (j == 7)
{
kprintf("..%02x [%d]\n", bitx->array[(i / 8) - 1], i);
j = 0;
continue;
}
j++;
}
if (j != 0)
kprintf("..%02x [%d]\n", bitx->array[i / 8], i);
}
/**
* Init a BitArray.
*
* The BitArray uses an external array for storage. You can use the macro
* BITARRAY_ALLOC to declare an appropriate memory size. Example usage:
* \code
* BITARRAY_ALLOC(bits_mem, 17);
* BitArray bits;
* bitarray_init(&bits, 17, bits_mem, sizeof(bits_mem))
* \endcode
*
* \param bitx BitArray context
* \param bitarray_len Number of bits in the BitArray
* \param array Memory area for the BitArray
* \param size Size (in bytes) of the memory area \a array
*/
INLINE void bitarray_init(BitArray *bitx, size_t bitarray_len, uint8_t *array, size_t size)
{
bitx->size = size;
bitx->array = array;
bitx->bitarray_len = bitarray_len;
}
int bitarray_testSetup(void);
int bitarray_testRun(void);
int bitarray_testTearDown(void);
#endif /* STRUCT_BITARRAY_H */