1 /*****************************************************************************
2 * aout.c : QNX audio output
3 *****************************************************************************
4 * Copyright (C) 2000, 2001 the VideoLAN team
6 * Authors: Henri Fallon <henri@videolan.org>
7 * Jon Lech Johansen <jon-vl@nanocrew.net>
8 * Pascal Levesque <pascal.levesque@mindready.com>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
23 *****************************************************************************/
25 /*****************************************************************************
27 *****************************************************************************/
28 #include <errno.h> /* ENOMEM */
34 #include <vlc_common.h>
42 #include <sys/asoundlib.h>
46 snd_pcm_t * p_pcm_handle;
50 uint8_t * p_silent_buffer;
53 #define DEFAULT_FRAME_SIZE 2048
55 /*****************************************************************************
57 *****************************************************************************/
58 int OpenAudio ( vlc_object_t *p_this );
59 void CloseAudio ( vlc_object_t *p_this );
60 static int GetBufInfo ( aout_instance_t * );
61 static void Play ( aout_instance_t * );
62 static int QNXaoutThread ( aout_instance_t * );
64 /*****************************************************************************
65 * Open : creates a handle and opens an alsa device
66 *****************************************************************************
67 * This function opens an alsa device, through the alsa API
68 *****************************************************************************/
69 int OpenAudio( vlc_object_t *p_this )
71 aout_instance_t *p_aout = (aout_instance_t *)p_this;
73 int i_bytes_per_sample;
75 snd_pcm_channel_info_t pi;
76 snd_pcm_channel_params_t pp;
77 aout_instance_t *p_aout = (aout_instance_t *)p_this;
79 /* allocate structure */
80 p_aout->output.p_sys = malloc( sizeof( aout_sys_t ) );
81 if( p_aout->output.p_sys == NULL )
83 msg_Err( p_aout, "out of memory" );
87 /* open audio device */
88 if( ( i_ret = snd_pcm_open_preferred( &p_aout->output.p_sys->p_pcm_handle,
89 &p_aout->output.p_sys->i_card,
90 &p_aout->output.p_sys->i_device,
91 SND_PCM_OPEN_PLAYBACK ) ) < 0 )
93 msg_Err( p_aout, "unable to open audio device (%s)",
94 snd_strerror( i_ret ) );
95 free( p_aout->output.p_sys );
100 if( ( i_ret = snd_pcm_plugin_set_disable( p_aout->output.p_sys->p_pcm_handle,
101 PLUGIN_DISABLE_MMAP ) ) < 0 )
103 msg_Err( p_aout, "unable to disable mmap (%s)", snd_strerror(i_ret) );
104 CloseAudio( p_this );
105 free( p_aout->output.p_sys );
109 p_aout->output.p_sys->p_silent_buffer = malloc( DEFAULT_FRAME_SIZE * 4 );
110 p_aout->output.pf_play = Play;
111 aout_VolumeSoftInit( p_aout );
113 memset( &pi, 0, sizeof(pi) );
114 memset( &pp, 0, sizeof(pp) );
116 pi.channel = SND_PCM_CHANNEL_PLAYBACK;
117 if( ( i_ret = snd_pcm_plugin_info( p_aout->output.p_sys->p_pcm_handle,
120 msg_Err( p_aout, "unable to get plugin info (%s)",
121 snd_strerror( i_ret ) );
122 CloseAudio( p_this );
123 free( p_aout->output.p_sys );
127 pp.mode = SND_PCM_MODE_BLOCK;
128 pp.channel = SND_PCM_CHANNEL_PLAYBACK;
129 pp.start_mode = SND_PCM_START_FULL;
130 pp.stop_mode = SND_PCM_STOP_STOP;
132 pp.buf.block.frags_max = 3;
133 pp.buf.block.frags_min = 1;
135 pp.format.interleave = 1;
136 pp.format.rate = p_aout->output.output.i_rate;
138 i_nb_channels = aout_FormatNbChannels( &p_aout->output.output );
139 if ( i_nb_channels > 2 )
141 /* I don't know if QNX supports more than two channels. */
143 p_aout->output.output.i_channels = AOUT_CHAN_STEREO;
145 pp.format.voices = i_nb_channels;
147 p_aout->output.output.i_format = AOUT_FMT_S16_NE;
148 p_aout->output.i_nb_samples = DEFAULT_FRAME_SIZE;
149 pp.format.format = SND_PCM_SFMT_S16;
150 i_bytes_per_sample = 2;
152 pp.buf.block.frag_size = p_aout->output.i_nb_samples *
153 p_aout->output.output.i_channels *
157 if( ( i_ret = snd_pcm_plugin_params( p_aout->output.p_sys->p_pcm_handle,
160 msg_Err( p_aout, "unable to set parameters (%s)", snd_strerror(i_ret) );
161 CloseAudio( p_this );
162 free( p_aout->output.p_sys );
166 /* prepare channel */
167 if( ( i_ret = snd_pcm_plugin_prepare( p_aout->output.p_sys->p_pcm_handle,
168 SND_PCM_CHANNEL_PLAYBACK ) ) < 0 )
170 msg_Err( p_aout, "unable to prepare channel (%s)",
171 snd_strerror( i_ret ) );
172 CloseAudio( p_this );
173 free( p_aout->output.p_sys );
177 /* Create audio thread and wait for its readiness. */
178 if( vlc_thread_create( p_aout, "aout", QNXaoutThread,
179 VLC_THREAD_PRIORITY_OUTPUT, false ) )
181 msg_Err( p_aout, "cannot create QNX audio thread (%m)" );
182 CloseAudio( p_this );
183 free( p_aout->output.p_sys );
190 /*****************************************************************************
191 * GetBufInfo: buffer status query
192 *****************************************************************************
193 * This function returns the number of used byte in the queue.
194 * It also deals with errors : indeed if the device comes to run out
195 * of data to play, it switches to the "underrun" status. It has to
196 * be flushed and re-prepared
197 *****************************************************************************/
198 static int GetBufInfo( aout_instance_t *p_aout )
201 snd_pcm_channel_status_t status;
203 /* get current pcm status */
204 memset( &status, 0, sizeof(status) );
205 if( ( i_ret = snd_pcm_plugin_status( p_aout->output.p_sys->p_pcm_handle,
208 msg_Err( p_aout, "unable to get device status (%s)",
209 snd_strerror( i_ret ) );
213 /* check for underrun */
214 switch( status.status )
216 case SND_PCM_STATUS_READY:
217 case SND_PCM_STATUS_UNDERRUN:
218 if( ( i_ret = snd_pcm_plugin_prepare( p_aout->output.p_sys->p_pcm_handle,
219 SND_PCM_CHANNEL_PLAYBACK ) ) < 0 )
221 msg_Err( p_aout, "unable to prepare channel (%s)",
222 snd_strerror( i_ret ) );
227 return( status.count );
230 /*****************************************************************************
231 * Play : plays a sample
232 *****************************************************************************
233 * Plays a sample using the snd_pcm_write function from the alsa API
234 *****************************************************************************/
235 static void Play( aout_instance_t *p_aout )
239 /*****************************************************************************
240 * CloseAudio: close the audio device
241 *****************************************************************************/
242 void CloseAudio ( vlc_object_t *p_this )
244 aout_instance_t *p_aout = (aout_instance_t *)p_this;
247 vlc_object_kill( p_aout );
248 vlc_thread_join( p_aout );
250 if( ( i_ret = snd_pcm_close( p_aout->output.p_sys->p_pcm_handle ) ) < 0 )
252 msg_Err( p_aout, "unable to close audio device (%s)",
253 snd_strerror( i_ret ) );
256 free( p_aout->output.p_sys->p_silent_buffer );
257 free( p_aout->output.p_sys );
261 /*****************************************************************************
262 * QNXaoutThread: asynchronous thread used to DMA the data to the device
263 *****************************************************************************/
264 static int QNXaoutThread( aout_instance_t * p_aout )
266 struct aout_sys_t * p_sys = p_aout->output.p_sys;
268 while ( vlc_object_alive (p_aout) )
270 aout_buffer_t * p_buffer;
274 if ( p_aout->output.output.i_format != VLC_FOURCC('s','p','d','i') )
276 mtime_t next_date = 0;
278 /* Get the presentation date of the next write() operation. It
279 * is equal to the current date + duration of buffered samples.
280 * Order is important here, since GetBufInfo is believed to take
281 * more time than mdate(). */
282 next_date = (mtime_t)GetBufInfo( p_aout ) * 1000000
283 / p_aout->output.output.i_bytes_per_frame
284 / p_aout->output.output.i_rate
285 * p_aout->output.output.i_frame_length;
286 next_date += mdate();
288 p_buffer = aout_OutputNextBuffer( p_aout, next_date, false );
292 p_buffer = aout_OutputNextBuffer( p_aout, 0, true );
295 if ( p_buffer != NULL )
297 p_bytes = p_buffer->p_buffer;
298 i_size = p_buffer->i_nb_bytes;
302 i_size = DEFAULT_FRAME_SIZE / p_aout->output.output.i_frame_length
303 * p_aout->output.output.i_bytes_per_frame;
304 p_bytes = p_aout->output.p_sys->p_silent_buffer;
305 memset( p_bytes, 0, i_size );
308 i_tmp = snd_pcm_plugin_write( p_aout->output.p_sys->p_pcm_handle,
314 msg_Err( p_aout, "write failed (%m)" );
317 if ( p_buffer != NULL )
319 aout_BufferFree( p_buffer );