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() */
40 #include <sys/asoundlib.h>
44 snd_pcm_t * p_pcm_handle;
48 byte_t * p_silent_buffer;
51 #define DEFAULT_FRAME_SIZE 2048
53 /*****************************************************************************
55 *****************************************************************************/
56 int E_(OpenAudio) ( vlc_object_t *p_this );
57 void E_(CloseAudio) ( vlc_object_t *p_this );
58 static int GetBufInfo ( aout_instance_t * );
59 static void Play ( aout_instance_t * );
60 static int QNXaoutThread ( aout_instance_t * );
62 /*****************************************************************************
63 * Open : creates a handle and opens an alsa device
64 *****************************************************************************
65 * This function opens an alsa device, through the alsa API
66 *****************************************************************************/
67 int E_(OpenAudio)( vlc_object_t *p_this )
69 aout_instance_t *p_aout = (aout_instance_t *)p_this;
71 int i_bytes_per_sample;
73 snd_pcm_channel_info_t pi;
74 snd_pcm_channel_params_t pp;
75 aout_instance_t *p_aout = (aout_instance_t *)p_this;
77 /* allocate structure */
78 p_aout->output.p_sys = malloc( sizeof( aout_sys_t ) );
79 if( p_aout->output.p_sys == NULL )
81 msg_Err( p_aout, "out of memory" );
85 /* open audio device */
86 if( ( i_ret = snd_pcm_open_preferred( &p_aout->output.p_sys->p_pcm_handle,
87 &p_aout->output.p_sys->i_card,
88 &p_aout->output.p_sys->i_device,
89 SND_PCM_OPEN_PLAYBACK ) ) < 0 )
91 msg_Err( p_aout, "unable to open audio device (%s)",
92 snd_strerror( i_ret ) );
93 free( p_aout->output.p_sys );
98 if( ( i_ret = snd_pcm_plugin_set_disable( p_aout->output.p_sys->p_pcm_handle,
99 PLUGIN_DISABLE_MMAP ) ) < 0 )
101 msg_Err( p_aout, "unable to disable mmap (%s)", snd_strerror(i_ret) );
102 E_(CloseAudio)( p_this );
103 free( p_aout->output.p_sys );
107 p_aout->output.p_sys->p_silent_buffer = malloc( DEFAULT_FRAME_SIZE * 4 );
108 p_aout->output.pf_play = Play;
109 aout_VolumeSoftInit( p_aout );
111 memset( &pi, 0, sizeof(pi) );
112 memset( &pp, 0, sizeof(pp) );
114 pi.channel = SND_PCM_CHANNEL_PLAYBACK;
115 if( ( i_ret = snd_pcm_plugin_info( p_aout->output.p_sys->p_pcm_handle,
118 msg_Err( p_aout, "unable to get plugin info (%s)",
119 snd_strerror( i_ret ) );
120 E_(CloseAudio)( p_this );
121 free( p_aout->output.p_sys );
125 pp.mode = SND_PCM_MODE_BLOCK;
126 pp.channel = SND_PCM_CHANNEL_PLAYBACK;
127 pp.start_mode = SND_PCM_START_FULL;
128 pp.stop_mode = SND_PCM_STOP_STOP;
130 pp.buf.block.frags_max = 3;
131 pp.buf.block.frags_min = 1;
133 pp.format.interleave = 1;
134 pp.format.rate = p_aout->output.output.i_rate;
136 i_nb_channels = aout_FormatNbChannels( &p_aout->output.output );
137 if ( i_nb_channels > 2 )
139 /* I don't know if QNX supports more than two channels. */
141 p_aout->output.output.i_channels = AOUT_CHAN_STEREO;
143 pp.format.voices = i_nb_channels;
145 p_aout->output.output.i_format = AOUT_FMT_S16_NE;
146 p_aout->output.i_nb_samples = DEFAULT_FRAME_SIZE;
147 pp.format.format = SND_PCM_SFMT_S16;
148 i_bytes_per_sample = 2;
150 pp.buf.block.frag_size = p_aout->output.i_nb_samples *
151 p_aout->output.output.i_channels *
155 if( ( i_ret = snd_pcm_plugin_params( p_aout->output.p_sys->p_pcm_handle,
158 msg_Err( p_aout, "unable to set parameters (%s)", snd_strerror(i_ret) );
159 E_(CloseAudio)( p_this );
160 free( p_aout->output.p_sys );
164 /* prepare channel */
165 if( ( i_ret = snd_pcm_plugin_prepare( p_aout->output.p_sys->p_pcm_handle,
166 SND_PCM_CHANNEL_PLAYBACK ) ) < 0 )
168 msg_Err( p_aout, "unable to prepare channel (%s)",
169 snd_strerror( i_ret ) );
170 E_(CloseAudio)( p_this );
171 free( p_aout->output.p_sys );
175 /* Create audio thread and wait for its readiness. */
176 if( vlc_thread_create( p_aout, "aout", QNXaoutThread,
177 VLC_THREAD_PRIORITY_OUTPUT, VLC_FALSE ) )
179 msg_Err( p_aout, "cannot create QNX audio thread (%s)", strerror(errno) );
180 E_(CloseAudio)( p_this );
181 free( p_aout->output.p_sys );
188 /*****************************************************************************
189 * GetBufInfo: buffer status query
190 *****************************************************************************
191 * This function returns the number of used byte in the queue.
192 * It also deals with errors : indeed if the device comes to run out
193 * of data to play, it switches to the "underrun" status. It has to
194 * be flushed and re-prepared
195 *****************************************************************************/
196 static int GetBufInfo( aout_instance_t *p_aout )
199 snd_pcm_channel_status_t status;
201 /* get current pcm status */
202 memset( &status, 0, sizeof(status) );
203 if( ( i_ret = snd_pcm_plugin_status( p_aout->output.p_sys->p_pcm_handle,
206 msg_Err( p_aout, "unable to get device status (%s)",
207 snd_strerror( i_ret ) );
211 /* check for underrun */
212 switch( status.status )
214 case SND_PCM_STATUS_READY:
215 case SND_PCM_STATUS_UNDERRUN:
216 if( ( i_ret = snd_pcm_plugin_prepare( p_aout->output.p_sys->p_pcm_handle,
217 SND_PCM_CHANNEL_PLAYBACK ) ) < 0 )
219 msg_Err( p_aout, "unable to prepare channel (%s)",
220 snd_strerror( i_ret ) );
225 return( status.count );
228 /*****************************************************************************
229 * Play : plays a sample
230 *****************************************************************************
231 * Plays a sample using the snd_pcm_write function from the alsa API
232 *****************************************************************************/
233 static void Play( aout_instance_t *p_aout )
237 /*****************************************************************************
238 * CloseAudio: close the audio device
239 *****************************************************************************/
240 void E_(CloseAudio) ( vlc_object_t *p_this )
242 aout_instance_t *p_aout = (aout_instance_t *)p_this;
245 vlc_object_kill( p_aout );
246 vlc_thread_join( p_aout );
248 if( ( i_ret = snd_pcm_close( p_aout->output.p_sys->p_pcm_handle ) ) < 0 )
250 msg_Err( p_aout, "unable to close audio device (%s)",
251 snd_strerror( i_ret ) );
254 free( p_aout->output.p_sys->p_silent_buffer );
255 free( p_aout->output.p_sys );
259 /*****************************************************************************
260 * QNXaoutThread: asynchronous thread used to DMA the data to the device
261 *****************************************************************************/
262 static int QNXaoutThread( aout_instance_t * p_aout )
264 struct aout_sys_t * p_sys = p_aout->output.p_sys;
266 while ( !p_aout->b_die )
268 aout_buffer_t * p_buffer;
272 if ( p_aout->output.output.i_format != VLC_FOURCC('s','p','d','i') )
274 mtime_t next_date = 0;
276 /* Get the presentation date of the next write() operation. It
277 * is equal to the current date + duration of buffered samples.
278 * Order is important here, since GetBufInfo is believed to take
279 * more time than mdate(). */
280 next_date = (mtime_t)GetBufInfo( p_aout ) * 1000000
281 / p_aout->output.output.i_bytes_per_frame
282 / p_aout->output.output.i_rate
283 * p_aout->output.output.i_frame_length;
284 next_date += mdate();
286 p_buffer = aout_OutputNextBuffer( p_aout, next_date, VLC_FALSE );
290 p_buffer = aout_OutputNextBuffer( p_aout, 0, VLC_TRUE );
293 if ( p_buffer != NULL )
295 p_bytes = p_buffer->p_buffer;
296 i_size = p_buffer->i_nb_bytes;
300 i_size = DEFAULT_FRAME_SIZE / p_aout->output.output.i_frame_length
301 * p_aout->output.output.i_bytes_per_frame;
302 p_bytes = p_aout->output.p_sys->p_silent_buffer;
303 memset( p_bytes, 0, i_size );
306 i_tmp = snd_pcm_plugin_write( p_aout->output.p_sys->p_pcm_handle,
312 msg_Err( p_aout, "write failed (%s)", strerror(errno) );
315 if ( p_buffer != NULL )
317 aout_BufferFree( p_buffer );