alsa-lib/src/control/bag.c

86 lines
2.3 KiB
C

/*
* Control Interface - highlevel API - hcontrol bag operations
* Copyright (c) 2000 by Jaroslav Kysela <perex@suse.cz>
*
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Library General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <assert.h>
#define __USE_GNU
#include <search.h>
#include "control_local.h"
int snd_ctl_hbag_create(void **bag)
{
assert(bag != NULL);
*bag = NULL;
return 0;
}
static void snd_ctl_hbag_free_private(snd_hcontrol_t *hcontrol ATTRIBUTE_UNUSED)
{
/* nothing */
}
int snd_ctl_hbag_destroy(void **bag, void (*hcontrol_free)(snd_hcontrol_t *hcontrol))
{
assert(bag != NULL);
if (hcontrol_free == NULL)
hcontrol_free = snd_ctl_hbag_free_private;
tdestroy(*bag, (__free_fn_t)hcontrol_free);
*bag = NULL;
return 0;
}
int snd_ctl_hbag_add(void **bag, snd_hcontrol_t *hcontrol)
{
void *res;
assert(bag != NULL && hcontrol != NULL);
res = tsearch(hcontrol, bag, (__compar_fn_t)snd_ctl_hsort);
if (res == NULL)
return -ENOMEM;
if ((snd_hcontrol_t *)res == hcontrol)
return -EALREADY;
return 0;
}
int snd_ctl_hbag_del(void **bag, snd_hcontrol_t *hcontrol)
{
assert(bag != NULL && hcontrol != NULL);
if (tdelete(hcontrol, bag, (__compar_fn_t)snd_ctl_hsort) == NULL)
return -ENOENT;
return 0;
}
snd_hcontrol_t *snd_ctl_hbag_find(void **bag, snd_control_id_t *id)
{
void *res;
assert(bag != NULL && id != NULL);
if (*bag == NULL)
return NULL;
res = tfind(id, bag, (__compar_fn_t)snd_ctl_hsort);
return res == NULL ? NULL : *(snd_hcontrol_t **)res;
}