1 /*
2 * Linux audio play and grab interface
3 * Copyright (c) 2000, 2001 Fabrice Bellard
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg 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 * FFmpeg 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 FFmpeg; 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_UNISTD_H
27 #include <unistd.h>
28 #endif
29 #include <fcntl.h>
30 #include <sys/ioctl.h>
31 #include <sys/soundcard.h>
32
33 #include "libavutil/log.h"
34
35 #include "avdevice.h"
36
37 #include "oss.h"
38
ff_oss_audio_open(AVFormatContext * s1,int is_output,const char * audio_device)39 int ff_oss_audio_open(AVFormatContext *s1, int is_output,
40 const char *audio_device)
41 {
42 OSSAudioData *s = s1->priv_data;
43 int audio_fd;
44 int tmp, err;
45 char *flip = getenv("AUDIO_FLIP_LEFT");
46
47 if (is_output)
48 audio_fd = avpriv_open(audio_device, O_WRONLY);
49 else
50 audio_fd = avpriv_open(audio_device, O_RDONLY);
51 if (audio_fd < 0) {
52 av_log(s1, AV_LOG_ERROR, "%s: %s\n", audio_device, av_err2str(AVERROR(errno)));
53 return AVERROR(EIO);
54 }
55
56 if (flip && *flip == '1') {
57 s->flip_left = 1;
58 }
59
60 /* non blocking mode */
61 if (!is_output) {
62 if (fcntl(audio_fd, F_SETFL, O_NONBLOCK) < 0) {
63 av_log(s1, AV_LOG_WARNING, "%s: Could not enable non block mode (%s)\n", audio_device, av_err2str(AVERROR(errno)));
64 }
65 }
66
67 s->frame_size = OSS_AUDIO_BLOCK_SIZE;
68
69 #define CHECK_IOCTL_ERROR(event) \
70 if (err < 0) { \
71 av_log(s1, AV_LOG_ERROR, #event ": %s\n", av_err2str(AVERROR(errno)));\
72 goto fail; \
73 }
74
75 /* select format : favour native format
76 * We don't CHECK_IOCTL_ERROR here because even if failed OSS still may be
77 * usable. If OSS is not usable the SNDCTL_DSP_SETFMTS later is going to
78 * fail anyway. */
79 err = ioctl(audio_fd, SNDCTL_DSP_GETFMTS, &tmp);
80 if (err < 0) {
81 av_log(s1, AV_LOG_WARNING, "SNDCTL_DSP_GETFMTS: %s\n", av_err2str(AVERROR(errno)));
82 }
83
84 #if HAVE_BIGENDIAN
85 if (tmp & AFMT_S16_BE) {
86 tmp = AFMT_S16_BE;
87 } else if (tmp & AFMT_S16_LE) {
88 tmp = AFMT_S16_LE;
89 } else {
90 tmp = 0;
91 }
92 #else
93 if (tmp & AFMT_S16_LE) {
94 tmp = AFMT_S16_LE;
95 } else if (tmp & AFMT_S16_BE) {
96 tmp = AFMT_S16_BE;
97 } else {
98 tmp = 0;
99 }
100 #endif
101
102 switch(tmp) {
103 case AFMT_S16_LE:
104 s->codec_id = AV_CODEC_ID_PCM_S16LE;
105 s->sample_size = 2;
106 break;
107 case AFMT_S16_BE:
108 s->codec_id = AV_CODEC_ID_PCM_S16BE;
109 s->sample_size = 2;
110 break;
111 default:
112 av_log(s1, AV_LOG_ERROR, "Soundcard does not support 16 bit sample format\n");
113 close(audio_fd);
114 return AVERROR(EIO);
115 }
116 err=ioctl(audio_fd, SNDCTL_DSP_SETFMT, &tmp);
117 CHECK_IOCTL_ERROR(SNDCTL_DSP_SETFMT)
118
119 tmp = (s->channels == 2);
120 err = ioctl(audio_fd, SNDCTL_DSP_STEREO, &tmp);
121 CHECK_IOCTL_ERROR(SNDCTL_DSP_STEREO)
122
123 tmp = s->sample_rate;
124 err = ioctl(audio_fd, SNDCTL_DSP_SPEED, &tmp);
125 CHECK_IOCTL_ERROR(SNDCTL_DSP_SPEED)
126 s->sample_rate = tmp; /* store real sample rate */
127 s->fd = audio_fd;
128
129 return 0;
130 fail:
131 close(audio_fd);
132 return AVERROR(EIO);
133 #undef CHECK_IOCTL_ERROR
134 }
135
ff_oss_audio_close(OSSAudioData * s)136 int ff_oss_audio_close(OSSAudioData *s)
137 {
138 close(s->fd);
139 return 0;
140 }
141