linux/linux-5.4.31/tools/lib/bitmap.c

74 lines
1.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* From lib/bitmap.c
* Helper functions for bitmap.h.
*/
#include <linux/bitmap.h>
int __bitmap_weight(const unsigned long *bitmap, int bits)
{
int k, w = 0, lim = bits/BITS_PER_LONG;
for (k = 0; k < lim; k++)
w += hweight_long(bitmap[k]);
if (bits % BITS_PER_LONG)
w += hweight_long(bitmap[k] & BITMAP_LAST_WORD_MASK(bits));
return w;
}
void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
const unsigned long *bitmap2, int bits)
{
int k;
int nr = BITS_TO_LONGS(bits);
for (k = 0; k < nr; k++)
dst[k] = bitmap1[k] | bitmap2[k];
}
size_t bitmap_scnprintf(unsigned long *bitmap, int nbits,
char *buf, size_t size)
{
/* current bit is 'cur', most recently seen range is [rbot, rtop] */
int cur, rbot, rtop;
bool first = true;
size_t ret = 0;
rbot = cur = find_first_bit(bitmap, nbits);
while (cur < nbits) {
rtop = cur;
cur = find_next_bit(bitmap, nbits, cur + 1);
if (cur < nbits && cur <= rtop + 1)
continue;
if (!first)
ret += scnprintf(buf + ret, size - ret, ",");
first = false;
ret += scnprintf(buf + ret, size - ret, "%d", rbot);
if (rbot < rtop)
ret += scnprintf(buf + ret, size - ret, "-%d", rtop);
rbot = cur;
}
return ret;
}
int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
const unsigned long *bitmap2, unsigned int bits)
{
unsigned int k;
unsigned int lim = bits/BITS_PER_LONG;
unsigned long result = 0;
for (k = 0; k < lim; k++)
result |= (dst[k] = bitmap1[k] & bitmap2[k]);
if (bits % BITS_PER_LONG)
result |= (dst[k] = bitmap1[k] & bitmap2[k] &
BITMAP_LAST_WORD_MASK(bits));
return result != 0;
}