diff options
-rw-r--r-- | Makefile.am | 3 | ||||
-rw-r--r-- | bitmap.c | 116 | ||||
-rw-r--r-- | bitmap.h | 185 | ||||
-rw-r--r-- | bitmap_i.h | 68 |
4 files changed, 372 insertions, 0 deletions
diff --git a/Makefile.am b/Makefile.am index 7018878..b5d255d 100644 --- a/Makefile.am +++ b/Makefile.am @@ -18,6 +18,9 @@ librbraun_la_SOURCES = \ avltree.c \ avltree.h \ avltree_i.h \ + bitmap.c \ + bitmap.h \ + bitmap_i.h \ cpu.h \ error.c \ error.h \ diff --git a/bitmap.c b/bitmap.c new file mode 100644 index 0000000..7ac1662 --- /dev/null +++ b/bitmap.c @@ -0,0 +1,116 @@ +/* + * Copyright (c) 2013-2015 Richard Braun. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. 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. + * + * 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 <limits.h> +#include <stddef.h> +#include <string.h> + +#include "bitmap.h" +#include "bitmap_i.h" + +int +bitmap_cmp(const unsigned long *a, const unsigned long *b, int nr_bits) +{ + unsigned long last_a, last_b, mask; + int n, rv; + + n = BITMAP_LONGS(nr_bits) - 1; + + if (n != 0) { + rv = memcmp(a, b, n * sizeof(unsigned long)); + + if (rv != 0) + return rv; + + nr_bits -= n * LONG_BIT; + } + + last_a = a[n]; + last_b = b[n]; + + if (nr_bits != LONG_BIT) { + mask = (1UL << nr_bits) - 1; + last_a &= mask; + last_b &= mask; + } + + if (last_a == last_b) + return 0; + else if (last_a < last_b) + return -1; + else + return 1; +} + +static inline unsigned long +bitmap_find_next_compute_complement(unsigned long word, int nr_bits) +{ + if (nr_bits < LONG_BIT) + word |= (((unsigned long)-1) << nr_bits); + + return ~word; +} + +int +bitmap_find_next_bit(const unsigned long *bm, int nr_bits, int bit, + int complement) +{ + const unsigned long *start, *end; + unsigned long word; + + start = bm; + end = bm + BITMAP_LONGS(nr_bits); + + if (bit >= LONG_BIT) { + bitmap_lookup(bm, bit); + nr_bits -= ((bm - start) * LONG_BIT); + } + + word = *bm; + + if (complement) + word = bitmap_find_next_compute_complement(word, nr_bits); + + if (bit < LONG_BIT) + word &= ~(bitmap_mask(bit) - 1); + + for (;;) { + bit = __builtin_ffsl(word); + + if (bit != 0) + return ((bm - start) * LONG_BIT) + bit - 1; + + bm++; + + if (bm >= end) + return -1; + + nr_bits -= LONG_BIT; + word = *bm; + + if (complement) + word = bitmap_find_next_compute_complement(word, nr_bits); + } +} diff --git a/bitmap.h b/bitmap.h new file mode 100644 index 0000000..9e6efad --- /dev/null +++ b/bitmap.h @@ -0,0 +1,185 @@ +/* + * Copyright (c) 2013-2015 Richard Braun. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. 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. + * + * 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. + * + * + * Arbitrary-length bit arrays. + * + * Most functions do not check whether the given parameters are valid. This + * is the responsibility of the caller. + */ + +#ifndef _BITMAP_H +#define _BITMAP_H + +#include <limits.h> +#include <string.h> + +#include "bitmap_i.h" +#include "x86/atomic.h" + +#define BITMAP_DECLARE(name, nr_bits) unsigned long name[BITMAP_LONGS(nr_bits)] + +int bitmap_cmp(const unsigned long *a, const unsigned long *b, int nr_bits); + +static inline void +bitmap_zero(unsigned long *bm, int nr_bits) +{ + int n; + + n = BITMAP_LONGS(nr_bits); + memset(bm, 0, n * sizeof(unsigned long)); +} + +static inline void +bitmap_fill(unsigned long *bm, int nr_bits) +{ + int n; + + n = BITMAP_LONGS(nr_bits); + memset(bm, 0xff, n * sizeof(unsigned long)); +} + +static inline void +bitmap_copy(unsigned long *dest, const unsigned long *src, int nr_bits) +{ + int n; + + n = BITMAP_LONGS(nr_bits); + memcpy(dest, src, n * sizeof(unsigned long)); +} + +static inline void +bitmap_set(unsigned long *bm, int bit) +{ + if (bit >= LONG_BIT) + bitmap_lookup(bm, bit); + + *bm |= bitmap_mask(bit); +} + +static inline void +bitmap_set_atomic(unsigned long *bm, int bit) +{ + if (bit >= LONG_BIT) + bitmap_lookup(bm, bit); + + atomic_or_ulong(bm, bitmap_mask(bit)); +} + +static inline void +bitmap_clear(unsigned long *bm, int bit) +{ + if (bit >= LONG_BIT) + bitmap_lookup(bm, bit); + + *bm &= ~bitmap_mask(bit); +} + +static inline void +bitmap_clear_atomic(unsigned long *bm, int bit) +{ + if (bit >= LONG_BIT) + bitmap_lookup(bm, bit); + + atomic_and_ulong(bm, ~bitmap_mask(bit)); +} + +static inline int +bitmap_test(const unsigned long *bm, int bit) +{ + if (bit >= LONG_BIT) + bitmap_lookup(bm, bit); + + return ((*bm & bitmap_mask(bit)) != 0); +} + +static inline void +bitmap_and(unsigned long *a, const unsigned long *b, int nr_bits) +{ + int i, n; + + n = BITMAP_LONGS(nr_bits); + + for (i = 0; i < n; i++) + a[i] &= b[i]; +} + +static inline void +bitmap_or(unsigned long *a, const unsigned long *b, int nr_bits) +{ + int i, n; + + n = BITMAP_LONGS(nr_bits); + + for (i = 0; i < n; i++) + a[i] |= b[i]; +} + +static inline void +bitmap_xor(unsigned long *a, const unsigned long *b, int nr_bits) +{ + int i, n; + + n = BITMAP_LONGS(nr_bits); + + for (i = 0; i < n; i++) + a[i] ^= b[i]; +} + +static inline int +bitmap_find_next(const unsigned long *bm, int nr_bits, int bit) +{ + return bitmap_find_next_bit(bm, nr_bits, bit, 0); +} + +static inline int +bitmap_find_first(const unsigned long *bm, int nr_bits) +{ + return bitmap_find_next(bm, nr_bits, 0); +} + +static inline int +bitmap_find_next_zero(const unsigned long *bm, int nr_bits, int bit) +{ + return bitmap_find_next_bit(bm, nr_bits, bit, 1); +} + +static inline int +bitmap_find_first_zero(const unsigned long *bm, int nr_bits) +{ + return bitmap_find_next_zero(bm, nr_bits, 0); +} + +#define bitmap_for_each(bm, nr_bits, bit) \ +for ((bit) = 0; \ + ((bit) < nr_bits) \ + && (((bit) = bitmap_find_next(bm, nr_bits, bit)) != -1); \ + (bit)++) + +#define bitmap_for_each_zero(bm, nr_bits, bit) \ +for ((bit) = 0; \ + ((bit) < nr_bits) \ + && (((bit) = bitmap_find_next_zero(bm, nr_bits, bit)) != -1); \ + (bit)++) + +#endif /* _BITMAP_H */ diff --git a/bitmap_i.h b/bitmap_i.h new file mode 100644 index 0000000..45208f3 --- /dev/null +++ b/bitmap_i.h @@ -0,0 +1,68 @@ +/* + * Copyright (c) 2013-2015 Richard Braun. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. 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. + * + * 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_I_H +#define _BITMAP_I_H + +#include <limits.h> + +#include "macros.h" + +#ifndef LONG_BIT +#define LONG_BIT ((int)(CHAR_BIT * sizeof(long))) +#endif /* LONG_BIT */ + +#define BITMAP_LONGS(nr_bits) DIV_CEIL(nr_bits, LONG_BIT) + +/* + * Adjust the bitmap pointer and the bit index so that the latter refers + * to a bit inside the word pointed by the former. + * + * Implemented as a macro for const-correctness. + */ +#define bitmap_lookup(bm, bit) \ +MACRO_BEGIN \ + int i; \ + \ + i = BITMAP_LONGS((bit) + 1) - 1; \ + (bm) += i; \ + (bit) -= i * LONG_BIT; \ +MACRO_END + +static inline unsigned long +bitmap_mask(int bit) +{ + return (1UL << bit); +} + +/* + * Return the index of the next set bit in the bitmap, starting (and + * including) the given bit index, or -1 if the bitmap is empty. If + * complement is true, bits are toggled before searching so that the + * result is the index of the next zero bit. + */ +int bitmap_find_next_bit(const unsigned long *bm, int nr_bits, int bit, + int complement); + +#endif /* _BITMAP_I_H */ |