ad52d78188b499431956d47c21ad6a113dd5b722
[libav.git] / libavdevice / oss_audio.c
1 /*
2 * Linux audio play and grab interface
3 * Copyright (c) 2000, 2001 Fabrice Bellard
4 *
5 * This file is part of Libav.
6 *
7 * Libav is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * Libav 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 GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #include "config.h"
23
24 #include <string.h>
25
26 #if HAVE_SOUNDCARD_H
27 #include <soundcard.h>
28 #else
29 #include <sys/soundcard.h>
30 #endif
31
32 #include <unistd.h>
33 #include <fcntl.h>
34 #include <sys/ioctl.h>
35
36 #include "libavutil/log.h"
37
38 #include "libavcodec/avcodec.h"
39
40 #include "libavformat/avformat.h"
41
42 #include "oss_audio.h"
43
44 int ff_oss_audio_open(AVFormatContext *s1, int is_output,
45 const char *audio_device)
46 {
47 OSSAudioData *s = s1->priv_data;
48 int audio_fd;
49 int tmp, err;
50 char *flip = getenv("AUDIO_FLIP_LEFT");
51
52 if (is_output)
53 audio_fd = avpriv_open(audio_device, O_WRONLY);
54 else
55 audio_fd = avpriv_open(audio_device, O_RDONLY);
56 if (audio_fd < 0) {
57 av_log(s1, AV_LOG_ERROR, "%s: %s\n", audio_device, strerror(errno));
58 return AVERROR(EIO);
59 }
60
61 if (flip && *flip == '1') {
62 s->flip_left = 1;
63 }
64
65 /* non blocking mode */
66 if (!is_output)
67 fcntl(audio_fd, F_SETFL, O_NONBLOCK);
68
69 s->frame_size = OSS_AUDIO_BLOCK_SIZE;
70
71 /* select format : favour native format */
72 err = ioctl(audio_fd, SNDCTL_DSP_GETFMTS, &tmp);
73
74 #if HAVE_BIGENDIAN
75 if (tmp & AFMT_S16_BE) {
76 tmp = AFMT_S16_BE;
77 } else if (tmp & AFMT_S16_LE) {
78 tmp = AFMT_S16_LE;
79 } else {
80 tmp = 0;
81 }
82 #else
83 if (tmp & AFMT_S16_LE) {
84 tmp = AFMT_S16_LE;
85 } else if (tmp & AFMT_S16_BE) {
86 tmp = AFMT_S16_BE;
87 } else {
88 tmp = 0;
89 }
90 #endif
91
92 switch(tmp) {
93 case AFMT_S16_LE:
94 s->codec_id = AV_CODEC_ID_PCM_S16LE;
95 break;
96 case AFMT_S16_BE:
97 s->codec_id = AV_CODEC_ID_PCM_S16BE;
98 break;
99 default:
100 av_log(s1, AV_LOG_ERROR, "Soundcard does not support 16 bit sample format\n");
101 close(audio_fd);
102 return AVERROR(EIO);
103 }
104 err=ioctl(audio_fd, SNDCTL_DSP_SETFMT, &tmp);
105 if (err < 0) {
106 av_log(s1, AV_LOG_ERROR, "SNDCTL_DSP_SETFMT: %s\n", strerror(errno));
107 goto fail;
108 }
109
110 tmp = (s->channels == 2);
111 err = ioctl(audio_fd, SNDCTL_DSP_STEREO, &tmp);
112 if (err < 0) {
113 av_log(s1, AV_LOG_ERROR, "SNDCTL_DSP_STEREO: %s\n", strerror(errno));
114 goto fail;
115 }
116
117 tmp = s->sample_rate;
118 err = ioctl(audio_fd, SNDCTL_DSP_SPEED, &tmp);
119 if (err < 0) {
120 av_log(s1, AV_LOG_ERROR, "SNDCTL_DSP_SPEED: %s\n", strerror(errno));
121 goto fail;
122 }
123 s->sample_rate = tmp; /* store real sample rate */
124 s->fd = audio_fd;
125
126 return 0;
127 fail:
128 close(audio_fd);
129 return AVERROR(EIO);
130 }
131
132 int ff_oss_audio_close(OSSAudioData *s)
133 {
134 close(s->fd);
135 return 0;
136 }