1 /*****************************************************************************
2 * sdl.c : SDL audio output plugin for vlc
3 *****************************************************************************
4 * Copyright (C) 2000-2002 VideoLAN
5 * $Id: sdl.c,v 1.2 2002/08/14 00:43:52 massiot Exp $
7 * Authors: Michel Kaempf <maxx@via.ecp.fr>
8 * Samuel Hocevar <sam@zoy.org>
9 * Pierre Baillet <oct@zoy.org>
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
24 *****************************************************************************/
26 /*****************************************************************************
28 *****************************************************************************/
29 #include <errno.h> /* ENOMEM */
30 #include <fcntl.h> /* open(), O_WRONLY */
31 #include <string.h> /* strerror() */
32 #include <unistd.h> /* write(), close() */
33 #include <stdlib.h> /* calloc(), malloc(), free() */
37 #include "aout_internal.h"
39 #include SDL_INCLUDE_FILE
41 #define FRAME_SIZE 2048*2
43 /*****************************************************************************
45 *****************************************************************************/
46 static int Open ( vlc_object_t * );
47 static void Close ( vlc_object_t * );
49 static int SetFormat ( aout_instance_t * );
50 static void Play ( aout_instance_t *, aout_buffer_t * );
52 static void SDLCallback ( void *, Uint8 *, int );
54 /*****************************************************************************
56 *****************************************************************************/
58 set_description( _("Simple DirectMedia Layer audio module") );
59 set_capability( "audio output", 40 );
60 set_callbacks( Open, Close );
63 /*****************************************************************************
64 * Open: open the audio device
65 *****************************************************************************/
66 static int Open ( vlc_object_t *p_this )
68 aout_instance_t *p_aout = (aout_instance_t *)p_this;
70 Uint32 i_flags = SDL_INIT_AUDIO;
72 if( SDL_WasInit( i_flags ) )
77 p_aout->output.pf_setformat = SetFormat;
78 p_aout->output.pf_play = Play;
81 /* Win32 SDL implementation doesn't support SDL_INIT_EVENTTHREAD yet*/
82 i_flags |= SDL_INIT_EVENTTHREAD;
85 /* In debug mode you may want vlc to dump a core instead of staying
87 i_flags |= SDL_INIT_NOPARACHUTE;
90 /* Initialize library */
91 if( SDL_Init( i_flags ) < 0 )
93 msg_Err( p_aout, "cannot initialize SDL (%s)", SDL_GetError() );
100 /*****************************************************************************
101 * SetFormat: reset the audio device and sets its format
102 *****************************************************************************/
103 static int SetFormat( aout_instance_t *p_aout )
105 /* TODO: finish and clean this */
106 SDL_AudioSpec desired;
108 desired.freq = p_aout->output.output.i_rate;
109 desired.format = AUDIO_S16SYS;
110 desired.channels = p_aout->output.output.i_channels;
111 desired.callback = SDLCallback;
112 desired.userdata = p_aout;
113 desired.samples = FRAME_SIZE;
115 /* Open the sound device - FIXME : get the "natural" parameters */
116 if( SDL_OpenAudio( &desired, NULL ) < 0 )
121 p_aout->output.output.i_format = AOUT_FMT_S16_NE;
122 p_aout->output.i_nb_samples = FRAME_SIZE;
129 /*****************************************************************************
130 * Play: play a sound samples buffer
131 *****************************************************************************/
132 static void Play( aout_instance_t * p_aout, aout_buffer_t * p_buffer )
134 SDL_LockAudio(); /* Stop callbacking */
136 aout_FifoPush( p_aout, &p_aout->output.fifo, p_buffer );
138 SDL_UnlockAudio(); /* go on callbacking */
141 /*****************************************************************************
142 * Close: close the audio device
143 *****************************************************************************/
144 static void Close ( vlc_object_t *p_this )
148 SDL_QuitSubSystem( SDL_INIT_AUDIO );
151 /*****************************************************************************
152 * SDLCallback: what to do once SDL has played sound samples
153 *****************************************************************************/
154 static void SDLCallback( void * _p_aout, byte_t * p_stream, int i_len )
156 aout_instance_t * p_aout = (aout_instance_t *)_p_aout;
157 /* FIXME : take into account SDL latency instead of mdate() */
158 aout_buffer_t * p_buffer = aout_OutputNextBuffer( p_aout, mdate(), 0 );
160 if ( i_len != FRAME_SIZE * sizeof(s16)
161 * p_aout->output.output.i_channels )
163 msg_Err( p_aout, "SDL doesn't know its buffer size (%d)", i_len );
166 if ( p_buffer != NULL )
168 p_aout->p_vlc->pf_memcpy( p_stream, p_buffer->p_buffer, i_len );
169 aout_BufferFree( p_buffer );
173 p_aout->p_vlc->pf_memset( p_stream, 0, i_len );