1 /*****************************************************************************
2 * esd.c : EsounD module
3 *****************************************************************************
4 * Copyright (C) 2000, 2001 VideoLAN
5 * $Id: esd.c,v 1.16 2003/01/28 03:46:22 sam Exp $
7 * Authors: Samuel Hocevar <sam@zoy.org>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
22 *****************************************************************************/
24 /*****************************************************************************
26 *****************************************************************************/
27 #include <errno.h> /* ENOMEM */
28 #include <fcntl.h> /* open(), O_WRONLY */
29 #include <string.h> /* strerror() */
30 #include <unistd.h> /* write(), close() */
31 #include <stdlib.h> /* calloc(), malloc(), free() */
35 #include "aout_internal.h"
39 /*****************************************************************************
40 * aout_sys_t: esd audio output method descriptor
41 *****************************************************************************
42 * This structure is part of the audio output thread descriptor.
43 * It describes some esd specific variables.
44 *****************************************************************************/
47 esd_format_t esd_format;
53 /*****************************************************************************
55 *****************************************************************************/
56 static int Open ( vlc_object_t * );
57 static void Close ( vlc_object_t * );
58 static void Play ( aout_instance_t * );
59 static int ESDThread ( aout_instance_t * );
60 static void ESDLoop ( aout_instance_t * );
62 /*****************************************************************************
64 *****************************************************************************/
66 set_description( _("EsounD audio module") );
67 set_capability( "audio output", 50 );
68 set_callbacks( Open, Close );
69 add_shortcut( "esound" );
72 /*****************************************************************************
73 * Open: open an esd socket
74 *****************************************************************************/
75 static int Open( vlc_object_t *p_this )
77 aout_instance_t *p_aout = (aout_instance_t *)p_this;
78 struct aout_sys_t * p_sys;
81 /* Allocate structure */
82 p_sys = malloc( sizeof( aout_sys_t ) );
85 msg_Err( p_aout, "out of memory" );
89 p_aout->output.p_sys = p_sys;
91 p_aout->output.pf_play = Play;
92 aout_VolumeSoftInit( p_aout );
94 /* Initialize some variables */
95 p_sys->esd_format = ESD_BITS16 | ESD_STREAM | ESD_PLAY;
96 p_sys->esd_format &= ~ESD_MASK_CHAN;
98 p_aout->output.output.i_format = AOUT_FMT_S16_NE;
99 i_nb_channels = aout_FormatNbChannels( &p_aout->output.output );
100 if ( i_nb_channels > 2 )
102 /* EsounD doesn't support more than two channels. */
104 p_aout->output.output.i_physical_channels =
105 AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT;
108 switch( i_nb_channels )
111 p_sys->esd_format |= ESD_MONO;
114 p_sys->esd_format |= ESD_STEREO;
118 /* open a socket for playing a stream
119 * and try to open /dev/dsp if there's no EsounD */
120 p_sys->i_fd = esd_play_stream_fallback( p_sys->esd_format,
121 p_aout->output.output.i_rate, NULL, "vlc" );
122 if( p_sys->i_fd < 0 )
124 msg_Err( p_aout, "cannot open esound socket (format 0x%08x at %d Hz)",
125 p_sys->esd_format, p_aout->output.output.i_rate );
130 p_aout->output.i_nb_samples = ESD_BUF_SIZE * 2;
132 /* ESD latency is calculated for 44100 Hz. We don't have any way to get the
133 * number of buffered samples, so I assume ESD_BUF_SIZE/2 */
135 (mtime_t)( esd_get_latency( esd_open_sound(NULL) ) + ESD_BUF_SIZE/2
136 * p_aout->output.output.i_bytes_per_frame
137 * p_aout->output.output.i_rate
140 / p_aout->output.output.i_bytes_per_frame
141 / p_aout->output.output.i_rate;
143 /* Create ESD thread and wait for its readiness. */
144 if( vlc_thread_create( p_aout, "aout", ESDThread,
145 VLC_THREAD_PRIORITY_OUTPUT, VLC_FALSE ) )
147 msg_Err( p_aout, "cannot create ESD thread (%s)", strerror(errno) );
148 close( p_sys->i_fd );
156 /*****************************************************************************
157 * Play: nothing to do
158 *****************************************************************************/
159 static void Play( aout_instance_t *p_aout )
163 /*****************************************************************************
164 * Close: close the Esound socket
165 *****************************************************************************/
166 static void Close( vlc_object_t *p_this )
168 aout_instance_t *p_aout = (aout_instance_t *)p_this;
169 struct aout_sys_t * p_sys = p_aout->output.p_sys;
172 vlc_thread_join( p_aout );
174 close( p_sys->i_fd );
178 /*****************************************************************************
179 * ESDThread: asynchronous thread used to DMA the data to the device
180 *****************************************************************************/
181 static int ESDThread( aout_instance_t * p_aout )
183 while ( !p_aout->b_die )
191 /*****************************************************************************
192 * ESDLoop: ESDThread's inner loop
193 *****************************************************************************
194 * This is a separate function because it makes use of alloca() which makes
195 * use of the caller's stack frame, which means we need to return after each
197 *****************************************************************************/
198 static void ESDLoop( aout_instance_t * p_aout )
200 struct aout_sys_t * p_sys = p_aout->output.p_sys;
201 aout_buffer_t * p_buffer;
203 byte_t * p_bytes = NULL;
205 /* Get the presentation date of the next write() operation. It
206 * is equal to the current date + buffered samples + esd latency */
207 p_buffer = aout_OutputNextBuffer( p_aout, mdate() + p_sys->latency,
210 if ( p_buffer != NULL )
212 p_bytes = p_buffer->p_buffer;
213 i_size = p_buffer->i_nb_bytes;
217 i_size = ESD_BUF_SIZE * 2
218 / p_aout->output.output.i_frame_length
219 * p_aout->output.output.i_bytes_per_frame;
220 p_bytes = alloca( i_size );
221 memset( p_bytes, 0, i_size );
224 i_tmp = write( p_sys->i_fd, p_bytes, i_size );
228 msg_Err( p_aout, "write failed (%s)", strerror(errno) );
231 if ( p_buffer != NULL )
233 aout_BufferFree( p_buffer );
238 /*****************************************************************************
239 * Play: play a sound samples buffer
240 *****************************************************************************
241 * This function writes a buffer of i_length bytes in the socket
242 *****************************************************************************/
243 static void Play( aout_thread_t *p_aout, byte_t *buffer, int i_size )
247 int m1 = p_aout->output.p_sys->esd_format & ESD_STEREO ? 1 : 2;
248 int m2 = p_aout->output.p_sys->esd_format & ESD_BITS16 ? 64 : 128;
250 i_amount = (m1 * 44100 * (ESD_BUF_SIZE + m1 * m2)) / p_aout->i_rate;
252 write( p_aout->output.p_sys->i_fd, buffer, i_size );