source: mainline/kernel/generic/include/adt/bitmap.h@ 063a74b9

/*
 * Copyright (c) 2006 Jakub Jermar
 * 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.
 */

/** @addtogroup genericadt
 * @{
 */
/** @file
 */

#ifndef KERN_BITMAP_H_
#define KERN_BITMAP_H_

#include <typedefs.h>

#define BITS2BYTES(bits)        (bits ? ((((bits)-1)>>3)+1) : 0)

typedef struct {
        uint8_t *map;
        size_t bits;
} bitmap_t;

extern void bitmap_initialize(bitmap_t *bitmap, uint8_t *map, size_t bits);
extern void bitmap_set_range(bitmap_t *bitmap, size_t start, size_t bits);
extern void bitmap_clear_range(bitmap_t *bitmap, size_t start, size_t bits);
extern void bitmap_copy(bitmap_t *dst, bitmap_t *src, size_t bits);

static inline int bitmap_get(bitmap_t *bitmap, size_t bit)
{
        if(bit >= bitmap->bits)
                return 0;
        
        return !! ((bitmap->map)[bit/8] & (1 << (bit & 7)));
}


#endif

/** @}
 */