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 */
29 #include <string.h> /* strerror() */
30 #include <stdlib.h> /* calloc(), malloc(), free() */
38 #include <<vlc_aout.h>>
39 #include "aout_internal.h"
41 #include <sys/asoundlib.h>
45 snd_pcm_t * p_pcm_handle;
49 byte_t * p_silent_buffer;
52 #define DEFAULT_FRAME_SIZE 2048
54 /*****************************************************************************
56 *****************************************************************************/
57 int E_(OpenAudio) ( vlc_object_t *p_this );
58 void E_(CloseAudio) ( vlc_object_t *p_this );
59 static int GetBufInfo ( aout_instance_t * );
60 static void Play ( aout_instance_t * );
61 static int QNXaoutThread ( aout_instance_t * );
63 /*****************************************************************************
64 * Open : creates a handle and opens an alsa device
65 *****************************************************************************
66 * This function opens an alsa device, through the alsa API
67 *****************************************************************************/
68 int E_(OpenAudio)( vlc_object_t *p_this )
70 aout_instance_t *p_aout = (aout_instance_t *)p_this;
72 int i_bytes_per_sample;
74 snd_pcm_channel_info_t pi;
75 snd_pcm_channel_params_t pp;
76 aout_instance_t *p_aout = (aout_instance_t *)p_this;
78 /* allocate structure */
79 p_aout->output.p_sys = malloc( sizeof( aout_sys_t ) );
80 if( p_aout->output.p_sys == NULL )
82 msg_Err( p_aout, "out of memory" );
86 /* open audio device */
87 if( ( i_ret = snd_pcm_open_preferred( &p_aout->output.p_sys->p_pcm_handle,
88 &p_aout->output.p_sys->i_card,
89 &p_aout->output.p_sys->i_device,
90 SND_PCM_OPEN_PLAYBACK ) ) < 0 )
92 msg_Err( p_aout, "unable to open audio device (%s)",
93 snd_strerror( i_ret ) );
94 free( p_aout->output.p_sys );
99 if( ( i_ret = snd_pcm_plugin_set_disable( p_aout->output.p_sys->p_pcm_handle,
100 PLUGIN_DISABLE_MMAP ) ) < 0 )
102 msg_Err( p_aout, "unable to disable mmap (%s)", snd_strerror(i_ret) );
103 E_(CloseAudio)( p_this );
104 free( p_aout->output.p_sys );
108 p_aout->output.p_sys->p_silent_buffer = malloc( DEFAULT_FRAME_SIZE * 4 );
109 p_aout->output.pf_play = Play;
110 aout_VolumeSoftInit( p_aout );
112 memset( &pi, 0, sizeof(pi) );
113 memset( &pp, 0, sizeof(pp) );
115 pi.channel = SND_PCM_CHANNEL_PLAYBACK;
116 if( ( i_ret = snd_pcm_plugin_info( p_aout->output.p_sys->p_pcm_handle,
119 msg_Err( p_aout, "unable to get plugin info (%s)",
120 snd_strerror( i_ret ) );
121 E_(CloseAudio)( p_this );
122 free( p_aout->output.p_sys );
126 pp.mode = SND_PCM_MODE_BLOCK;
127 pp.channel = SND_PCM_CHANNEL_PLAYBACK;
128 pp.start_mode = SND_PCM_START_FULL;
129 pp.stop_mode = SND_PCM_STOP_STOP;
131 pp.buf.block.frags_max = 3;
132 pp.buf.block.frags_min = 1;
134 pp.format.interleave = 1;
135 pp.format.rate = p_aout->output.output.i_rate;
137 i_nb_channels = aout_FormatNbChannels( &p_aout->output.output );
138 if ( i_nb_channels > 2 )
140 /* I don't know if QNX supports more than two channels. */
142 p_aout->output.output.i_channels = AOUT_CHAN_STEREO;
144 pp.format.voices = i_nb_channels;
146 p_aout->output.output.i_format = AOUT_FMT_S16_NE;
147 p_aout->output.i_nb_samples = DEFAULT_FRAME_SIZE;
148 pp.format.format = SND_PCM_SFMT_S16;
149 i_bytes_per_sample = 2;
151 pp.buf.block.frag_size = p_aout->output.i_nb_samples *
152 p_aout->output.output.i_channels *
156 if( ( i_ret = snd_pcm_plugin_params( p_aout->output.p_sys->p_pcm_handle,
159 msg_Err( p_aout, "unable to set parameters (%s)", snd_strerror(i_ret) );
160 E_(CloseAudio)( p_this );
161 free( p_aout->output.p_sys );
165 /* prepare channel */
166 if( ( i_ret = snd_pcm_plugin_prepare( p_aout->output.p_sys->p_pcm_handle,
167 SND_PCM_CHANNEL_PLAYBACK ) ) < 0 )
169 msg_Err( p_aout, "unable to prepare channel (%s)",
170 snd_strerror( i_ret ) );
171 E_(CloseAudio)( p_this );
172 free( p_aout->output.p_sys );
176 /* Create audio thread and wait for its readiness. */
177 if( vlc_thread_create( p_aout, "aout", QNXaoutThread,
178 VLC_THREAD_PRIORITY_OUTPUT, VLC_FALSE ) )
180 msg_Err( p_aout, "cannot create QNX audio thread (%s)", strerror(errno) );
181 E_(CloseAudio)( p_this );
182 free( p_aout->output.p_sys );
189 /*****************************************************************************
190 * GetBufInfo: buffer status query
191 *****************************************************************************
192 * This function returns the number of used byte in the queue.
193 * It also deals with errors : indeed if the device comes to run out
194 * of data to play, it switches to the "underrun" status. It has to
195 * be flushed and re-prepared
196 *****************************************************************************/
197 static int GetBufInfo( aout_instance_t *p_aout )
200 snd_pcm_channel_status_t status;
202 /* get current pcm status */
203 memset( &status, 0, sizeof(status) );
204 if( ( i_ret = snd_pcm_plugin_status( p_aout->output.p_sys->p_pcm_handle,
207 msg_Err( p_aout, "unable to get device status (%s)",
208 snd_strerror( i_ret ) );
212 /* check for underrun */
213 switch( status.status )
215 case SND_PCM_STATUS_READY:
216 case SND_PCM_STATUS_UNDERRUN:
217 if( ( i_ret = snd_pcm_plugin_prepare( p_aout->output.p_sys->p_pcm_handle,
218 SND_PCM_CHANNEL_PLAYBACK ) ) < 0 )
220 msg_Err( p_aout, "unable to prepare channel (%s)",
221 snd_strerror( i_ret ) );
226 return( status.count );
229 /*****************************************************************************
230 * Play : plays a sample
231 *****************************************************************************
232 * Plays a sample using the snd_pcm_write function from the alsa API
233 *****************************************************************************/
234 static void Play( aout_instance_t *p_aout )
238 /*****************************************************************************
239 * CloseAudio: close the audio device
240 *****************************************************************************/
241 void E_(CloseAudio) ( vlc_object_t *p_this )
243 aout_instance_t *p_aout = (aout_instance_t *)p_this;
247 vlc_thread_join( p_aout );
249 if( ( i_ret = snd_pcm_close( p_aout->output.p_sys->p_pcm_handle ) ) < 0 )
251 msg_Err( p_aout, "unable to close audio device (%s)",
252 snd_strerror( i_ret ) );
255 free( p_aout->output.p_sys->p_silent_buffer );
256 free( p_aout->output.p_sys );
260 /*****************************************************************************
261 * QNXaoutThread: asynchronous thread used to DMA the data to the device
262 *****************************************************************************/
263 static int QNXaoutThread( aout_instance_t * p_aout )
265 struct aout_sys_t * p_sys = p_aout->output.p_sys;
267 while ( !p_aout->b_die )
269 aout_buffer_t * p_buffer;
273 if ( p_aout->output.output.i_format != VLC_FOURCC('s','p','d','i') )
275 mtime_t next_date = 0;
277 /* Get the presentation date of the next write() operation. It
278 * is equal to the current date + duration of buffered samples.
279 * Order is important here, since GetBufInfo is believed to take
280 * more time than mdate(). */
281 next_date = (mtime_t)GetBufInfo( p_aout ) * 1000000
282 / p_aout->output.output.i_bytes_per_frame
283 / p_aout->output.output.i_rate
284 * p_aout->output.output.i_frame_length;
285 next_date += mdate();
287 p_buffer = aout_OutputNextBuffer( p_aout, next_date, VLC_FALSE );
291 p_buffer = aout_OutputNextBuffer( p_aout, 0, VLC_TRUE );
294 if ( p_buffer != NULL )
296 p_bytes = p_buffer->p_buffer;
297 i_size = p_buffer->i_nb_bytes;
301 i_size = DEFAULT_FRAME_SIZE / p_aout->output.output.i_frame_length
302 * p_aout->output.output.i_bytes_per_frame;
303 p_bytes = p_aout->output.p_sys->p_silent_buffer;
304 memset( p_bytes, 0, i_size );
307 i_tmp = snd_pcm_plugin_write( p_aout->output.p_sys->p_pcm_handle,
313 msg_Err( p_aout, "write failed (%s)", strerror(errno) );
316 if ( p_buffer != NULL )
318 aout_BufferFree( p_buffer );