1 /*
2 * From lib/bitmap.c
3 * Helper functions for bitmap.h.
4 *
5 * This source code is licensed under the GNU General Public License,
6 * Version 2. See the file COPYING for more details.
7 */
8 #include <linux/bitmap.h>
9
10 int __bitmap_weight(const unsigned long *bitmap, int bits)
11 {
12 int k, w = 0, lim = bits/BITS_PER_LONG;
13
14 for (k = 0; k < lim; k++)
15 w += hweight_long(bitmap[k]);
16
17 if (bits % BITS_PER_LONG)
18 w += hweight_long(bitmap[k] & BITMAP_LAST_WORD_MASK(bits));
19
20 return w;
21 }
22
23 void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
24 const unsigned long *bitmap2, int bits)
25 {
26 int k;
27 int nr = BITS_TO_LONGS(bits);
28
29 for (k = 0; k < nr; k++)
30 dst[k] = bitmap1[k] | bitmap2[k];
31 }
32
33 size_t bitmap_scnprintf(unsigned long *bitmap, int nbits,
34 char *buf, size_t size)
35 {
36 /* current bit is 'cur', most recently seen range is [rbot, rtop] */
37 int cur, rbot, rtop;
38 bool first = true;
39 size_t ret = 0;
40
41 rbot = cur = find_first_bit(bitmap, nbits);
42 while (cur < nbits) {
43 rtop = cur;
44 cur = find_next_bit(bitmap, nbits, cur + 1);
45 if (cur < nbits && cur <= rtop + 1)
46 continue;
47
48 if (!first)
49 ret += scnprintf(buf + ret, size - ret, ",");
50
51 first = false;
52
53 ret += scnprintf(buf + ret, size - ret, "%d", rbot);
54 if (rbot < rtop)
55 ret += scnprintf(buf + ret, size - ret, "-%d", rtop);
56
57 rbot = cur;
58 }
59 return ret;
60 }
61
62 int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
63 const unsigned long *bitmap2, unsigned int bits)
64 {
65 unsigned int k;
66 unsigned int lim = bits/BITS_PER_LONG;
67 unsigned long result = 0;
68
69 for (k = 0; k < lim; k++)
70 result |= (dst[k] = bitmap1[k] & bitmap2[k]);
71 if (bits % BITS_PER_LONG)
72 result |= (dst[k] = bitmap1[k] & bitmap2[k] &
73 BITMAP_LAST_WORD_MASK(bits));
74 return result != 0;
75 }
76
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.