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 */
38 #include <sys/asoundlib.h>
42 snd_pcm_t * p_pcm_handle;
46 byte_t * p_silent_buffer;
49 #define DEFAULT_FRAME_SIZE 2048
51 /*****************************************************************************
53 *****************************************************************************/
54 int E_(OpenAudio) ( vlc_object_t *p_this );
55 void E_(CloseAudio) ( vlc_object_t *p_this );
56 static int GetBufInfo ( aout_instance_t * );
57 static void Play ( aout_instance_t * );
58 static int QNXaoutThread ( aout_instance_t * );
60 /*****************************************************************************
61 * Open : creates a handle and opens an alsa device
62 *****************************************************************************
63 * This function opens an alsa device, through the alsa API
64 *****************************************************************************/
65 int E_(OpenAudio)( vlc_object_t *p_this )
67 aout_instance_t *p_aout = (aout_instance_t *)p_this;
69 int i_bytes_per_sample;
71 snd_pcm_channel_info_t pi;
72 snd_pcm_channel_params_t pp;
73 aout_instance_t *p_aout = (aout_instance_t *)p_this;
75 /* allocate structure */
76 p_aout->output.p_sys = malloc( sizeof( aout_sys_t ) );
77 if( p_aout->output.p_sys == NULL )
79 msg_Err( p_aout, "out of memory" );
83 /* open audio device */
84 if( ( i_ret = snd_pcm_open_preferred( &p_aout->output.p_sys->p_pcm_handle,
85 &p_aout->output.p_sys->i_card,
86 &p_aout->output.p_sys->i_device,
87 SND_PCM_OPEN_PLAYBACK ) ) < 0 )
89 msg_Err( p_aout, "unable to open audio device (%s)",
90 snd_strerror( i_ret ) );
91 free( p_aout->output.p_sys );
96 if( ( i_ret = snd_pcm_plugin_set_disable( p_aout->output.p_sys->p_pcm_handle,
97 PLUGIN_DISABLE_MMAP ) ) < 0 )
99 msg_Err( p_aout, "unable to disable mmap (%s)", snd_strerror(i_ret) );
100 E_(CloseAudio)( p_this );
101 free( p_aout->output.p_sys );
105 p_aout->output.p_sys->p_silent_buffer = malloc( DEFAULT_FRAME_SIZE * 4 );
106 p_aout->output.pf_play = Play;
107 aout_VolumeSoftInit( p_aout );
109 memset( &pi, 0, sizeof(pi) );
110 memset( &pp, 0, sizeof(pp) );
112 pi.channel = SND_PCM_CHANNEL_PLAYBACK;
113 if( ( i_ret = snd_pcm_plugin_info( p_aout->output.p_sys->p_pcm_handle,
116 msg_Err( p_aout, "unable to get plugin info (%s)",
117 snd_strerror( i_ret ) );
118 E_(CloseAudio)( p_this );
119 free( p_aout->output.p_sys );
123 pp.mode = SND_PCM_MODE_BLOCK;
124 pp.channel = SND_PCM_CHANNEL_PLAYBACK;
125 pp.start_mode = SND_PCM_START_FULL;
126 pp.stop_mode = SND_PCM_STOP_STOP;
128 pp.buf.block.frags_max = 3;
129 pp.buf.block.frags_min = 1;
131 pp.format.interleave = 1;
132 pp.format.rate = p_aout->output.output.i_rate;
134 i_nb_channels = aout_FormatNbChannels( &p_aout->output.output );
135 if ( i_nb_channels > 2 )
137 /* I don't know if QNX supports more than two channels. */
139 p_aout->output.output.i_channels = AOUT_CHAN_STEREO;
141 pp.format.voices = i_nb_channels;
143 p_aout->output.output.i_format = AOUT_FMT_S16_NE;
144 p_aout->output.i_nb_samples = DEFAULT_FRAME_SIZE;
145 pp.format.format = SND_PCM_SFMT_S16;
146 i_bytes_per_sample = 2;
148 pp.buf.block.frag_size = p_aout->output.i_nb_samples *
149 p_aout->output.output.i_channels *
153 if( ( i_ret = snd_pcm_plugin_params( p_aout->output.p_sys->p_pcm_handle,
156 msg_Err( p_aout, "unable to set parameters (%s)", snd_strerror(i_ret) );
157 E_(CloseAudio)( p_this );
158 free( p_aout->output.p_sys );
162 /* prepare channel */
163 if( ( i_ret = snd_pcm_plugin_prepare( p_aout->output.p_sys->p_pcm_handle,
164 SND_PCM_CHANNEL_PLAYBACK ) ) < 0 )
166 msg_Err( p_aout, "unable to prepare channel (%s)",
167 snd_strerror( i_ret ) );
168 E_(CloseAudio)( p_this );
169 free( p_aout->output.p_sys );
173 /* Create audio thread and wait for its readiness. */
174 if( vlc_thread_create( p_aout, "aout", QNXaoutThread,
175 VLC_THREAD_PRIORITY_OUTPUT, VLC_FALSE ) )
177 msg_Err( p_aout, "cannot create QNX audio thread (%m)" );
178 E_(CloseAudio)( p_this );
179 free( p_aout->output.p_sys );
186 /*****************************************************************************
187 * GetBufInfo: buffer status query
188 *****************************************************************************
189 * This function returns the number of used byte in the queue.
190 * It also deals with errors : indeed if the device comes to run out
191 * of data to play, it switches to the "underrun" status. It has to
192 * be flushed and re-prepared
193 *****************************************************************************/
194 static int GetBufInfo( aout_instance_t *p_aout )
197 snd_pcm_channel_status_t status;
199 /* get current pcm status */
200 memset( &status, 0, sizeof(status) );
201 if( ( i_ret = snd_pcm_plugin_status( p_aout->output.p_sys->p_pcm_handle,
204 msg_Err( p_aout, "unable to get device status (%s)",
205 snd_strerror( i_ret ) );
209 /* check for underrun */
210 switch( status.status )
212 case SND_PCM_STATUS_READY:
213 case SND_PCM_STATUS_UNDERRUN:
214 if( ( i_ret = snd_pcm_plugin_prepare( p_aout->output.p_sys->p_pcm_handle,
215 SND_PCM_CHANNEL_PLAYBACK ) ) < 0 )
217 msg_Err( p_aout, "unable to prepare channel (%s)",
218 snd_strerror( i_ret ) );
223 return( status.count );
226 /*****************************************************************************
227 * Play : plays a sample
228 *****************************************************************************
229 * Plays a sample using the snd_pcm_write function from the alsa API
230 *****************************************************************************/
231 static void Play( aout_instance_t *p_aout )
235 /*****************************************************************************
236 * CloseAudio: close the audio device
237 *****************************************************************************/
238 void E_(CloseAudio) ( vlc_object_t *p_this )
240 aout_instance_t *p_aout = (aout_instance_t *)p_this;
243 vlc_object_kill( p_aout );
244 vlc_thread_join( p_aout );
246 if( ( i_ret = snd_pcm_close( p_aout->output.p_sys->p_pcm_handle ) ) < 0 )
248 msg_Err( p_aout, "unable to close audio device (%s)",
249 snd_strerror( i_ret ) );
252 free( p_aout->output.p_sys->p_silent_buffer );
253 free( p_aout->output.p_sys );
257 /*****************************************************************************
258 * QNXaoutThread: asynchronous thread used to DMA the data to the device
259 *****************************************************************************/
260 static int QNXaoutThread( aout_instance_t * p_aout )
262 struct aout_sys_t * p_sys = p_aout->output.p_sys;
264 while ( !p_aout->b_die )
266 aout_buffer_t * p_buffer;
270 if ( p_aout->output.output.i_format != VLC_FOURCC('s','p','d','i') )
272 mtime_t next_date = 0;
274 /* Get the presentation date of the next write() operation. It
275 * is equal to the current date + duration of buffered samples.
276 * Order is important here, since GetBufInfo is believed to take
277 * more time than mdate(). */
278 next_date = (mtime_t)GetBufInfo( p_aout ) * 1000000
279 / p_aout->output.output.i_bytes_per_frame
280 / p_aout->output.output.i_rate
281 * p_aout->output.output.i_frame_length;
282 next_date += mdate();
284 p_buffer = aout_OutputNextBuffer( p_aout, next_date, VLC_FALSE );
288 p_buffer = aout_OutputNextBuffer( p_aout, 0, VLC_TRUE );
291 if ( p_buffer != NULL )
293 p_bytes = p_buffer->p_buffer;
294 i_size = p_buffer->i_nb_bytes;
298 i_size = DEFAULT_FRAME_SIZE / p_aout->output.output.i_frame_length
299 * p_aout->output.output.i_bytes_per_frame;
300 p_bytes = p_aout->output.p_sys->p_silent_buffer;
301 memset( p_bytes, 0, i_size );
304 i_tmp = snd_pcm_plugin_write( p_aout->output.p_sys->p_pcm_handle,
310 msg_Err( p_aout, "write failed (%m)" );
313 if ( p_buffer != NULL )
315 aout_BufferFree( p_buffer );