Index: Makefile =================================================================== --- Makefile (revision 50de918ee03e2d69dce7bc2641ba60d65d2fcbf7) +++ Makefile (revision 97a7effc811599a0a052715fae6d7e97c2fa066c) @@ -101,4 +101,5 @@ GENERIC_SOURCES = \ + generic/src/adt/bitmap.c \ generic/src/adt/btree.c \ generic/src/adt/hash_table.c \ Index: generic/include/adt/bitmap.h =================================================================== --- generic/include/adt/bitmap.h (revision 97a7effc811599a0a052715fae6d7e97c2fa066c) +++ generic/include/adt/bitmap.h (revision 97a7effc811599a0a052715fae6d7e97c2fa066c) @@ -0,0 +1,47 @@ +/* + * 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. + */ + +#ifndef __BITMAP_H__ +#define __BITMAP_H__ + +#include +#include + +#define BITS2BYTES(bits) ((((bits)-1)>>3)+1) + +typedef struct { + __u8 *map; + count_t bits; +} bitmap_t; + +extern void bitmap_initialize(bitmap_t *bitmap, __u8 *map, count_t bits); +extern void bitmap_set_range(bitmap_t *bitmap, index_t start, count_t bits); +extern void bitmap_clear_range(bitmap_t *bitmap, index_t start, count_t bits); +extern void bitmap_copy(bitmap_t *dst, bitmap_t *src, count_t bits); + +#endif Index: generic/src/adt/bitmap.c =================================================================== --- generic/src/adt/bitmap.c (revision 97a7effc811599a0a052715fae6d7e97c2fa066c) +++ generic/src/adt/bitmap.c (revision 97a7effc811599a0a052715fae6d7e97c2fa066c) @@ -0,0 +1,152 @@ +/* + * 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. + */ + +#include +#include +#include +#include +#include + +#define ALL_ONES 0xff +#define ALL_ZEROES 0x00 + +/** Initialize bitmap. + * + * No portion of the bitmap is set or cleared by this function. + * + * @param bitmap Bitmap structure. + * @param map Address of the memory used to hold the map. + * @param bits Number of bits stored in bitmap. + */ +void bitmap_initialize(bitmap_t *bitmap, __u8 *map, count_t bits) +{ + bitmap->map = map; + bitmap->bits = bits; +} + +/** Set range of bits. + * + * @param bitmap Bitmap structure. + * @param start Starting bit. + * @param bits Number of bits to set. + */ +void bitmap_set_range(bitmap_t *bitmap, index_t start, count_t bits) +{ + index_t i; + index_t aligned_start; + count_t lub; /* leading unaligned bits */ + count_t tub; /* trailing unaligned bits */ + + ASSERT(start + bits <= bitmap->bits); + + aligned_start = ALIGN_UP(start, 8); + lub = aligned_start - start; + tub = (bits - lub) % 8; + + if (lub) { + /* + * Make sure to set any leading unaligned bits. + */ + bitmap->map[start / 8] |= ~((1 << (8 - lub)) - 1); + } + for (i = 0; i < (bits - lub) / 8; i++) { + /* + * The middle bits can be set byte by byte. + */ + bitmap->map[aligned_start / 8 + i] = ALL_ONES; + } + if (tub) { + /* + * Make sure to set any trailing unaligned bits. + */ + bitmap->map[aligned_start / 8 + i] |= (1 << tub) - 1; + } + +} + +/** Clear range of bits. + * + * @param bitmap Bitmap structure. + * @param start Starting bit. + * @param bits Number of bits to clear. + */ +void bitmap_clear_range(bitmap_t *bitmap, index_t start, count_t bits) +{ + index_t i; + index_t aligned_start; + count_t lub; /* leading unaligned bits */ + count_t tub; /* trailing unaligned bits */ + + ASSERT(start + bits <= bitmap->bits); + + aligned_start = ALIGN_UP(start, 8); + lub = aligned_start - start; + tub = (bits - lub) % 8; + + if (lub) { + /* + * Make sure to clear any leading unaligned bits. + */ + bitmap->map[start / 8] &= (1 << (8 - lub)) - 1; + } + for (i = 0; i < (bits - lub) / 8; i++) { + /* + * The middle bits can be cleared byte by byte. + */ + bitmap->map[aligned_start / 8 + i] = ALL_ZEROES; + } + if (tub) { + /* + * Make sure to clear any trailing unaligned bits. + */ + bitmap->map[aligned_start / 8 + i] &= ~((1 << tub) - 1); + } + +} + +/** Copy portion of one bitmap into another bitmap. + * + * @param dst Destination bitmap. + * @param src Source bitmap. + * @param bits Number of bits to copy. + */ +void bitmap_copy(bitmap_t *dst, bitmap_t *src, count_t bits) +{ + index_t i; + + ASSERT(bits <= dst->bits); + ASSERT(bits <= src->bits); + + for (i = 0; i < bits / 8; i++) + dst->map[i] = src->map[i]; + + if (bits % 8) { + bitmap_clear_range(dst, i * 8, bits % 8); + dst->map[i] |= src->map[i] & ((1 << (bits % 8)) - 1); + } +}