2 Unix SMB/Netbios implementation.
4 simple bitmap functions
5 Copyright (C) Andrew Tridgell 1992-1998
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 extern int DEBUGLEVEL
;
26 /* these functions provide a simple way to allocate integers from a
27 pool without repitition */
30 /****************************************************************************
31 allocate a bitmap of the specified size
32 ****************************************************************************/
33 struct bitmap
*bitmap_allocate(int n
)
37 bm
= (struct bitmap
*)malloc(sizeof(*bm
));
42 bm
->b
= (uint32
*)malloc(sizeof(bm
->b
[0])*(n
+31)/32);
48 memset(bm
->b
, 0, sizeof(bm
->b
[0])*(n
+31)/32);
53 /****************************************************************************
55 ****************************************************************************/
57 void bitmap_free(struct bitmap
*bm
)
68 /****************************************************************************
70 ****************************************************************************/
71 BOOL
bitmap_set(struct bitmap
*bm
, unsigned i
)
74 DEBUG(0,("Setting invalid bitmap entry %d (of %d)\n",
78 bm
->b
[i
/32] |= (1<<(i
%32));
82 /****************************************************************************
83 clear a bit in a bitmap
84 ****************************************************************************/
85 BOOL
bitmap_clear(struct bitmap
*bm
, unsigned i
)
88 DEBUG(0,("clearing invalid bitmap entry %d (of %d)\n",
92 bm
->b
[i
/32] &= ~(1<<(i
%32));
96 /****************************************************************************
97 query a bit in a bitmap
98 ****************************************************************************/
99 BOOL
bitmap_query(struct bitmap
*bm
, unsigned i
)
101 if (i
>= bm
->n
) return False
;
102 if (bm
->b
[i
/32] & (1<<(i
%32))) {
108 /****************************************************************************
109 find a zero bit in a bitmap starting at the specified offset, with
111 ****************************************************************************/
112 int bitmap_find(struct bitmap
*bm
, unsigned ofs
)
116 if (ofs
> bm
->n
) ofs
= 0;
120 if (~(bm
->b
[i
/32])) {
123 if (!bitmap_query(bm
, j
)) return j
;
125 } while (j
& 31 && j
< bm
->n
);
133 if (~(bm
->b
[i
/32])) {
136 if (!bitmap_query(bm
, j
)) return j
;
138 } while (j
& 31 && j
< bm
->n
);