freebsd-skq/usr.sbin/pw/bitmap.c
pfg 7551d83c35 various: general adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

No functional change intended.
2017-11-27 15:37:16 +00:00

134 lines
3.0 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (C) 1996
* David L. Nugent. 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 DAVID L. NUGENT AND CONTRIBUTORS ``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 DAVID L. NUGENT OR CONTRIBUTORS 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 lint
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <stdlib.h>
#include <string.h>
#include "bitmap.h"
struct bitmap
bm_alloc(int size)
{
struct bitmap bm;
int szmap = (size / 8) + !!(size % 8);
bm.size = size;
bm.map = malloc(szmap);
if (bm.map)
memset(bm.map, 0, szmap);
return bm;
}
void
bm_dealloc(struct bitmap * bm)
{
free(bm->map);
}
static void
bm_getmask(int *pos, unsigned char *bmask)
{
*bmask = (unsigned char) (1 << (*pos % 8));
*pos /= 8;
}
void
bm_setbit(struct bitmap * bm, int pos)
{
unsigned char bmask;
bm_getmask(&pos, &bmask);
bm->map[pos] |= bmask;
}
void
bm_clrbit(struct bitmap * bm, int pos)
{
unsigned char bmask;
bm_getmask(&pos, &bmask);
bm->map[pos] &= ~bmask;
}
int
bm_isset(struct bitmap * bm, int pos)
{
unsigned char bmask;
bm_getmask(&pos, &bmask);
return !!(bm->map[pos] & bmask);
}
int
bm_firstunset(struct bitmap * bm)
{
int szmap = (bm->size / 8) + !!(bm->size % 8);
int at = 0;
int pos = 0;
while (pos < szmap) {
unsigned char bmv = bm->map[pos++];
unsigned char bmask = 1;
while (bmask & 0xff) {
if ((bmv & bmask) == 0)
return at;
bmask <<= 1;
++at;
}
}
return at;
}
int
bm_lastset(struct bitmap * bm)
{
int szmap = (bm->size / 8) + !!(bm->size % 8);
int at = 0;
int pos = 0;
int ofs = 0;
while (pos < szmap) {
unsigned char bmv = bm->map[pos++];
unsigned char bmask = 1;
while (bmask & 0xff) {
if ((bmv & bmask) != 0)
ofs = at;
bmask <<= 1;
++at;
}
}
return ofs;
}