1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
|
/* pcm_hw.c
** Copyright (c) 2019, The Linux Foundation.
**
** 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 <fcntl.h>
#include <stdarg.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <poll.h>
#include <sys/ioctl.h>
#include <linux/ioctl.h>
#include <sound/asound.h>
#include <tinyalsa/asoundlib.h>
#include "pcm_io.h"
struct pcm_hw_data {
/** Card number of the pcm device */
unsigned int card;
/** Device number for the pcm device */
unsigned int device;
/** File descriptor to the pcm device file node */
unsigned int fd;
/** Pointer to the pcm node from snd card definiton */
struct snd_node *node;
};
static void pcm_hw_close(void *data)
{
struct pcm_hw_data *hw_data = data;
if (hw_data->fd > 0)
close(hw_data->fd);
free(hw_data);
}
static int pcm_hw_ioctl(void *data, unsigned int cmd, ...)
{
struct pcm_hw_data *hw_data = data;
va_list ap;
void *arg;
va_start(ap, cmd);
arg = va_arg(ap, void *);
va_end(ap);
return ioctl(hw_data->fd, cmd, arg);
}
static int pcm_hw_open(unsigned int card, unsigned int device,
unsigned int flags, void **data, struct snd_node *node)
{
struct pcm_hw_data *hw_data;
char fn[256];
int fd;
hw_data = calloc(1, sizeof(*hw_data));
if (!hw_data) {
return -ENOMEM;
}
snprintf(fn, sizeof(fn), "/dev/snd/pcmC%uD%u%c", card, device,
flags & PCM_IN ? 'c' : 'p');
if (flags & PCM_NONBLOCK)
fd = open(fn, O_RDWR|O_NONBLOCK);
else
fd = open(fn, O_RDWR);
if (fd < 0) {
free(hw_data);
return fd;
}
hw_data->card = card;
hw_data->device = device;
hw_data->fd = fd;
hw_data->node = node;
*data = hw_data;
return fd;
}
const struct pcm_ops hw_ops = {
.open = pcm_hw_open,
.close = pcm_hw_close,
.ioctl = pcm_hw_ioctl,
};
|