You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

150 lines
3.9 KiB

/* snd_utils.c
**
** Copyright (c) 2019, The Linux Foundation. All rights reserved.
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * 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.
** * Neither the name of The Linux Foundation nor the names of its
** contributors may be used to endorse or promote products derived
** from this software without specific prior written permission.
**
** THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
** WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER 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.
**/
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include "snd_utils.h"
#define SND_DLSYM(h, p, s, err) \
do { \
err = 0; \
p = dlsym(h, s); \
if (!p) \
err = -ENODEV; \
} while(0)
int snd_utils_get_int(struct snd_node *node, const char *prop, int *val)
{
if (!node || !node->card_node || !node->dev_node)
return SND_NODE_TYPE_HW;
return node->get_int(node->dev_node, prop, val);
}
int snd_utils_get_str(struct snd_node *node, const char *prop, char **val)
{
if (!node || !node->card_node || !node->dev_node)
return SND_NODE_TYPE_HW;
return node->get_str(node->dev_node, prop, val);
}
void snd_utils_put_dev_node(struct snd_node *node)
{
if (!node)
return;
if (node->card_node)
node->put_card(node->card_node);
if (node->dl_hdl)
dlclose(node->dl_hdl);
free(node);
}
enum snd_node_type snd_utils_get_node_type(struct snd_node *node)
{
int val = SND_NODE_TYPE_HW;
if (!node || !node->card_node || !node->dev_node)
return SND_NODE_TYPE_HW;
node->get_int(node->dev_node, "type", &val);
return val;
};
static int snd_utils_resolve_symbols(struct snd_node *node)
{
void *dl = node->dl_hdl;
int err;
SND_DLSYM(dl, node->get_card, "snd_card_def_get_card", err);
if (err)
goto done;
SND_DLSYM(dl, node->put_card, "snd_card_def_put_card", err);
if (err)
goto done;
SND_DLSYM(dl, node->get_node, "snd_card_def_get_node", err);
if (err)
goto done;
SND_DLSYM(dl, node->get_int, "snd_card_def_get_int", err);
if (err)
goto done;
SND_DLSYM(dl, node->get_str, "snd_card_def_get_str", err);
done:
return err;
}
struct snd_node *snd_utils_get_dev_node(unsigned int card,
unsigned int device, int dev_type)
{
struct snd_node *node;
int rc = 0;
node = calloc(1, sizeof(*node));
if (!node)
return NULL;
node->dl_hdl = dlopen("libsndcardparser.so", RTLD_NOW);
if (!node->dl_hdl) {
goto err_dl_open;
}
rc = snd_utils_resolve_symbols(node);
if (rc < 0)
goto err_resolve_symbols;
node->card_node = node->get_card(card);
if (!node->card_node)
goto err_resolve_symbols;
node->dev_node = node->get_node(node->card_node,
device, dev_type);
if (!node->dev_node)
goto err_get_node;
return node;
err_get_node:
node->put_card(node->card_node);
err_resolve_symbols:
dlclose(node->dl_hdl);
err_dl_open:
free(node);
return NULL;
}