* oss.c : OSS /dev/dsp module for vlc
*****************************************************************************
* Copyright (C) 2000-2002 VideoLAN
- * $Id: oss.c,v 1.9 2002/08/14 00:23:59 massiot Exp $
+ * $Id: oss.c,v 1.20 2002/08/29 23:53:22 massiot Exp $
*
* Authors: Michel Kaempf <maxx@via.ecp.fr>
* Samuel Hocevar <sam@zoy.org>
volatile vlc_bool_t b_initialized;
};
-#define FRAME_SIZE 2048
+#define FRAME_SIZE 1024
+#define FRAME_COUNT 8
#define A52_FRAME_NB 1536
/*****************************************************************************
static void Close ( vlc_object_t * );
static int SetFormat ( aout_instance_t * );
-static void Play ( aout_instance_t *, aout_buffer_t * );
+static void Play ( aout_instance_t * );
static int OSSThread ( aout_instance_t * );
/*****************************************************************************
* Module descriptor
*****************************************************************************/
vlc_module_begin();
- add_category_hint( N_("Audio"), NULL );
+ add_category_hint( N_("OSS"), NULL );
add_file( "dspdev", "/dev/dsp", NULL, N_("OSS dsp device"), NULL );
set_description( _("Linux OSS /dev/dsp module") );
set_capability( "audio output", 100 );
+ add_shortcut( "dsp" );
set_callbacks( Open, Close );
vlc_module_end();
if( p_sys == NULL )
{
msg_Err( p_aout, "out of memory" );
- return 1;
+ return VLC_ENOMEM;
}
/* Initialize some variables */
{
msg_Err( p_aout, "no audio device given (maybe /dev/dsp ?)" );
free( p_sys );
- return -1;
+ return VLC_EGENERIC;
}
/* Open the sound device */
msg_Err( p_aout, "cannot open audio device (%s)", psz_device );
free( psz_device );
free( p_sys );
- return -1;
+ return VLC_EGENERIC;
}
free( psz_device );
/* Create OSS thread and wait for its readiness. */
p_sys->b_initialized = VLC_FALSE;
- if( vlc_thread_create( p_aout, "aout", OSSThread, VLC_FALSE ) )
+ if( vlc_thread_create( p_aout, "aout", OSSThread,
+ VLC_THREAD_PRIORITY_OUTPUT, VLC_FALSE ) )
{
msg_Err( p_aout, "cannot create OSS thread (%s)", strerror(errno) );
+ close( p_sys->i_fd );
free( psz_device );
free( p_sys );
- return -1;
+ return VLC_ETHREAD;
}
p_aout->output.pf_setformat = SetFormat;
p_aout->output.pf_play = Play;
- return 0;
+ return VLC_SUCCESS;
}
/*****************************************************************************
struct aout_sys_t * p_sys = p_aout->output.p_sys;
int i_format;
int i_rate;
+ int i_fragments;
vlc_bool_t b_stereo;
p_sys->b_initialized = VLC_FALSE;
if( ioctl( p_sys->i_fd, SNDCTL_DSP_RESET, NULL ) < 0 )
{
msg_Err( p_aout, "cannot reset OSS audio device" );
- return -1;
+ return VLC_EGENERIC;
+ }
+
+ /* Set the fragment size */
+ i_fragments = FRAME_COUNT << 16 | FRAME_SIZE;
+ if( ioctl( p_sys->i_fd, SNDCTL_DSP_SETFRAGMENT, &i_fragments ) < 0 )
+ {
+ msg_Err( p_aout, "cannot set fragment size (%.8x)", i_fragments );
+ return VLC_EGENERIC;
}
/* Set the output format */
if ( p_aout->output.output.i_format == AOUT_FMT_SPDIF )
{
+ i_format = AOUT_FMT_SPDIF;
p_aout->output.i_nb_samples = A52_FRAME_NB;
- p_aout->output.output.i_bytes_per_sec = p_aout->output.output.i_rate
- * AOUT_SPDIF_SIZE / A52_FRAME_NB;
+ p_aout->output.output.i_bytes_per_frame = AOUT_SPDIF_SIZE;
+ p_aout->output.output.i_frame_length = A52_FRAME_NB;
}
else
{
if( ioctl( p_sys->i_fd, SNDCTL_DSP_SETFMT, &i_format ) < 0
|| i_format != p_aout->output.output.i_format )
{
- msg_Err( p_aout, "cannot set audio output format (%i)",
- i_format );
- return -1;
+ msg_Err( p_aout, "cannot set audio output format (%i)", i_format );
+ return VLC_EGENERIC;
}
if ( p_aout->output.output.i_format != AOUT_FMT_SPDIF )
{
msg_Err( p_aout, "cannot set number of audio channels (%i)",
p_aout->output.output.i_channels );
- return -1;
+ return VLC_EGENERIC;
}
if ( b_stereo + 1 != p_aout->output.output.i_channels )
{
msg_Err( p_aout, "cannot set audio output rate (%i)",
p_aout->output.output.i_rate );
- return -1;
+ return VLC_EGENERIC;
}
if( i_rate != p_aout->output.output.i_rate )
p_sys->b_initialized = VLC_TRUE;
- return 0;
+ return VLC_SUCCESS;
}
/*****************************************************************************
* Play: queue a buffer for playing by OSSThread
*****************************************************************************/
-static void Play( aout_instance_t *p_aout, aout_buffer_t * p_buffer )
+static void Play( aout_instance_t *p_aout )
{
- aout_FifoPush( p_aout, &p_aout->output.fifo, p_buffer );
}
/*****************************************************************************
aout_instance_t *p_aout = (aout_instance_t *)p_this;
struct aout_sys_t * p_sys = p_aout->output.p_sys;
- p_aout->b_die = 1;
+ p_aout->b_die = VLC_TRUE;
vlc_thread_join( p_aout );
+ p_aout->b_die = VLC_FALSE;
+ ioctl( p_sys->i_fd, SNDCTL_DSP_RESET, NULL );
close( p_sys->i_fd );
+
free( p_sys );
}
/*****************************************************************************
- * GetBufInfo: buffer status query
+ * BufferDuration: buffer status query
*****************************************************************************
- * This function fills in the audio_buf_info structure :
- * - returns : number of available fragments (not partially used ones)
- * - int fragstotal : total number of fragments allocated
- * - int fragsize : size of a fragment in bytes
- * - int bytes : available space in bytes (includes partially used fragments)
- * Note! 'bytes' could be more than fragments*fragsize
+ * This function returns the duration in microseconfs of the current buffer.
*****************************************************************************/
-static int GetBufInfo( aout_instance_t * p_aout )
+static mtime_t BufferDuration( aout_instance_t * p_aout )
{
struct aout_sys_t * p_sys = p_aout->output.p_sys;
audio_buf_info audio_buf;
+ int i_bytes;
+ /* Fill the audio_buf_info structure:
+ * - fragstotal: total number of fragments allocated
+ * - fragsize: size of a fragment in bytes
+ * - bytes: available space in bytes (includes partially used fragments)
+ * Note! 'bytes' could be more than fragments*fragsize */
ioctl( p_sys->i_fd, SNDCTL_DSP_GETOSPACE, &audio_buf );
- /* returns the allocated space in bytes */
- return ( (audio_buf.fragstotal * audio_buf.fragsize) - audio_buf.bytes );
+ /* calculate number of available fragments (not partially used ones) */
+ i_bytes = (audio_buf.fragstotal * audio_buf.fragsize) - audio_buf.bytes;
+
+ /* Return the fragment duration */
+ return (mtime_t)i_bytes * 1000000
+ / p_aout->output.output.i_bytes_per_frame
+ / p_aout->output.output.i_rate
+ * p_aout->output.output.i_frame_length;
}
/*****************************************************************************
static int OSSThread( aout_instance_t * p_aout )
{
struct aout_sys_t * p_sys = p_aout->output.p_sys;
+ mtime_t next_date = 0;
while ( !p_aout->b_die )
{
aout_buffer_t * p_buffer;
- mtime_t next_date = 0;
int i_tmp, i_size;
byte_t * p_bytes;
if ( p_aout->output.output.i_format != AOUT_FMT_SPDIF )
{
- /* Get the presentation date of the next write() operation. It
- * is equal to the current date + duration of buffered samples.
- * Order is important here, since GetBufInfo is believed to take
- * more time than mdate(). */
- next_date = (mtime_t)GetBufInfo( p_aout ) * 1000000
- / aout_FormatToByterate( &p_aout->output.output );
- next_date += mdate();
+ mtime_t buffered = BufferDuration( p_aout );
+
+ /* Wait a bit - we don't want our buffer to be full */
+ while( buffered > AOUT_PTS_TOLERANCE * 2 )
+ {
+ msleep( buffered / 2 - 10000 );
+ buffered = BufferDuration( p_aout );
+ }
+
+ if( !next_date )
+ {
+ /* This is the _real_ presentation date */
+ next_date = mdate() + buffered;
+ }
+ else
+ {
+ /* Give a hint to the audio output about our drift, but
+ * not too much because we want to make it happy with our
+ * nicely calculated dates. */
+ next_date = ( (next_date * 7) + (mdate() + buffered) ) / 8;
+ }
+
+ /* Next buffer will be played at mdate()+buffered */
+ p_buffer = aout_OutputNextBuffer( p_aout, next_date, VLC_FALSE );
+ }
+ else
+ {
+ p_buffer = aout_OutputNextBuffer( p_aout, 0, VLC_TRUE );
}
-
- p_buffer = aout_OutputNextBuffer( p_aout, next_date );
if ( p_buffer != NULL )
{
p_bytes = p_buffer->p_buffer;
i_size = p_buffer->i_nb_bytes;
+ /* This is theoretical ... we'll see next iteration whether
+ * we're drifting */
+ next_date += p_buffer->end_date - p_buffer->start_date;
}
else
{
- i_size = aout_FormatToByterate( &p_aout->output.output )
- * FRAME_SIZE
- / p_aout->output.output.i_rate;
- p_bytes = alloca( i_size );
+ i_size = FRAME_SIZE / p_aout->output.output.i_frame_length
+ * p_aout->output.output.i_bytes_per_frame;
+ p_bytes = malloc( i_size );
memset( p_bytes, 0, i_size );
+ next_date = 0;
}
i_tmp = write( p_sys->i_fd, p_bytes, i_size );
{
aout_BufferFree( p_buffer );
}
+ else
+ {
+ free( p_bytes );
+ }
}
- return 0;
+ return VLC_SUCCESS;
}
projects / vlc / blobdiff