2 * This file is part of DisOrder.
3 * Copyright (C) 2009 Richard Kettlewell
5 * This program is free software: you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation, either version 3 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 /** @file lib/uaudio-oss.c
19 * @brief Support for OSS backend */
22 #if HAVE_SYS_SOUNDCARD_H || EMPEG_HOST
24 #if HAVE_SYS_SOUNDCARD_H
25 # include <sys/soundcard.h>
27 #include <sys/ioctl.h>
35 #include "configuration.h"
38 # if BYTE_ORDER == BIG_ENDIAN
39 # define AFMT_U16_NE AFMT_U16_BE
41 # define AFMT_U16_NE AFMT_U16_LE
45 /* documentation does not match implementation! */
46 #ifndef SOUND_MIXER_READ
47 # define SOUND_MIXER_READ(x) MIXER_READ(x)
49 #ifndef SOUND_MIXER_WRITE
50 # define SOUND_MIXER_WRITE(x) MIXER_WRITE(x)
53 static int oss_fd = -1;
54 static int oss_mixer_fd = -1;
55 static int oss_mixer_channel;
57 static const char *const oss_options[] = {
64 /** @brief Actually play sound via OSS */
65 static size_t oss_play(void *buffer, size_t samples) {
66 const size_t bytes = samples * uaudio_sample_size;
67 int rc = write(oss_fd, buffer, bytes);
69 fatal(errno, "error writing to sound device");
70 return rc / uaudio_sample_size;
73 /** @brief Open the OSS sound device */
74 static void oss_open(void) {
75 const char *device = uaudio_get("device", NULL);
78 if(!device || !*device || !strcmp(device, "default"))
81 if(!device || !*device || !strcmp(device, "default")) {
82 if(access("/dev/dsp", W_OK) == 0)
85 device = "/dev/audio";
88 if((oss_fd = open(device, O_WRONLY, 0)) < 0)
89 fatal(errno, "error opening %s", device);
91 int stereo = (uaudio_channels == 2), format;
92 if(ioctl(oss_fd, SNDCTL_DSP_STEREO, &stereo) < 0)
93 fatal(errno, "error calling ioctl SNDCTL_DSP_STEREO %d", stereo);
95 format = uaudio_signed ? AFMT_S16_NE : AFMT_U16_NE;
97 format = uaudio_signed ? AFMT_S8 : AFMT_U8;
98 if(ioctl(oss_fd, SNDCTL_DSP_SETFMT, &format) < 0)
99 fatal(errno, "error calling ioctl SNDCTL_DSP_SETFMT %#x", format);
100 int rate = uaudio_rate;
101 if(ioctl(oss_fd, SNDCTL_DSP_SPEED, &rate) < 0)
102 fatal(errno, "error calling ioctl SNDCTL_DSP_SPEED %d", rate);
103 if(rate != uaudio_rate)
104 error(0, "asked for %dHz, got %dHz", uaudio_rate, rate);
108 static void oss_activate(void) {
110 uaudio_thread_activate();
113 static void oss_deactivate(void) {
114 uaudio_thread_deactivate();
119 static void oss_start(uaudio_callback *callback,
121 if(uaudio_channels != 1 && uaudio_channels != 2)
122 fatal(0, "asked for %d channels but only support 1 or 2",
124 if(uaudio_bits != 8 && uaudio_bits != 16)
125 fatal(0, "asked for %d bits/channel but only support 8 or 16",
128 /* Very specific buffer size requirements here apparently */
129 uaudio_thread_start(callback, userdata, oss_play,
130 4608 / uaudio_sample_size,
131 4608 / uaudio_sample_size);
133 /* We could SNDCTL_DSP_GETBLKSIZE but only when the device is already open,
134 * which is kind of inconvenient. We go with 1-4Kbyte for now. */
135 uaudio_thread_start(callback, userdata, oss_play,
136 32 / uaudio_sample_size,
137 4096 / uaudio_sample_size);
141 static void oss_stop(void) {
142 uaudio_thread_stop();
145 /** @brief Channel names */
146 static const char *oss_channels[] = SOUND_DEVICE_NAMES;
148 static int oss_mixer_find_channel(const char *channel) {
149 if(!channel[strspn(channel, "0123456789")])
150 return atoi(channel);
152 for(unsigned n = 0; n < sizeof oss_channels / sizeof *oss_channels; ++n)
153 if(!strcmp(oss_channels[n], channel))
159 static void oss_open_mixer(void) {
160 const char *mixer = uaudio_get("mixer-device", "/dev/mixer");
161 /* TODO infer mixer-device from device */
162 if((oss_mixer_fd = open(mixer, O_RDWR, 0)) < 0)
163 fatal(errno, "error opening %s", mixer);
164 const char *channel = uaudio_get("mixer-channel", "pcm");
165 oss_mixer_channel = oss_mixer_find_channel(channel);
166 if(oss_mixer_channel < 0)
167 fatal(0, "no such channel as '%s'", channel);
170 static void oss_close_mixer(void) {
175 static void oss_get_volume(int *left, int *right) {
179 if(ioctl(oss_mixer_fd, SOUND_MIXER_READ(oss_mixer_channel), &r) < 0)
180 error(errno, "error getting volume");
183 *right = (r >> 8) & 0xff;
187 static void oss_set_volume(int *left, int *right) {
188 int r = (*left & 0xff) + (*right & 0xff) * 256;
189 if(ioctl(oss_mixer_fd, SOUND_MIXER_WRITE(oss_mixer_channel), &r) == -1)
190 error(errno, "error setting volume");
191 else if(ioctl(oss_mixer_fd, SOUND_MIXER_READ(oss_mixer_channel), &r) < 0)
192 error(errno, "error getting volume");
195 *right = (r >> 8) & 0xff;
199 static void oss_configure(void) {
200 uaudio_set("device", config->device);
201 uaudio_set("mixer-device", config->mixer);
202 uaudio_set("mixer-channel", config->channel);
205 const struct uaudio uaudio_oss = {
207 .options = oss_options,
210 .activate = oss_activate,
211 .deactivate = oss_deactivate,
212 .open_mixer = oss_open_mixer,
213 .close_mixer = oss_close_mixer,
214 .get_volume = oss_get_volume,
215 .set_volume = oss_set_volume,
216 .configure = oss_configure,