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 ****************************************************************************/
56 BOOL bitmap_set(struct bitmap *bm, unsigned i)
59 DEBUG(0,("Setting invalid bitmap entry %d (of %d)\n",
63 bm->b[i/32] |= (1<<(i%32));
67 /****************************************************************************
68 clear a bit in a bitmap
69 ****************************************************************************/
70 BOOL bitmap_clear(struct bitmap *bm, unsigned i)
73 DEBUG(0,("clearing invalid bitmap entry %d (of %d)\n",
77 bm->b[i/32] &= ~(1<<(i%32));
81 /****************************************************************************
82 query a bit in a bitmap
83 ****************************************************************************/
84 BOOL bitmap_query(struct bitmap *bm, unsigned i)
86 if (i >= bm->n) return False;
87 if (bm->b[i/32] & (1<<(i%32))) {
93 /****************************************************************************
94 find a zero bit in a bitmap starting at the specified offset, with
96 ****************************************************************************/
97 int bitmap_find(struct bitmap *bm, unsigned ofs)
101 if (ofs > bm->n) ofs = 0;
105 if (~(bm->b[i/32])) {
108 if (!bitmap_query(bm, j)) return j;
110 } while (j & 31 && j < bm->n);
118 if (~(bm->b[i/32])) {
121 if (!bitmap_query(bm, j)) return j;
123 } while (j & 31 && j < bm->n);