/** request that the IO thread perform a seek and rebuffer. This is
called for each Disk_Stream whenever the RT thread determines that
the transport has jumped to a new position. This is called *before*
process. */
void
Playback_DS::seek ( nframes_t frame )
{
THREAD_ASSERT( RT );
/* FIXME: non-RT-safe IO */
DMESSAGE( "requesting seek to frame %lu", (unsigned long)frame );
if ( seek_pending() )
printf( "seek error, attempt to seek while seek is pending\n" );
_pending_seek = frame;
flush();
}
/** request that the IO thread perform a seek and rebuffer. This is
called for each Disk_Stream whenever the RT thread determines that
the transport has jumped to a new position. This is called *before*
process. */
void
Playback_DS::seek ( nframes_t frame )
{
THREAD_ASSERT( RT );
/* FIXME: non-RT-safe IO */
DMESSAGE( "requesting seek to frame %lu", (unsigned long)frame );
if ( seek_pending() )
printf( "seek error, attempt to seek while seek is pending\n" );
_seek_frame = frame;
_pending_seek = true;
/* wake the IO thread */
block_processed();
}
void
Playback_DS::disk_thread ( void )
{
_thread.name( "Playback" );
DMESSAGE( "playback thread running" );
/* buffer to hold the interleaved data returned by the track reader */
sample_t *buf = new sample_t[ _nframes * channels() * _disk_io_blocks ];
#ifndef AVOID_UNNECESSARY_COPYING
sample_t *cbuf = new sample_t[ _nframes * _disk_io_blocks ];
#endif
int blocks_ready = 0;
const nframes_t nframes = _nframes * _disk_io_blocks;
while ( wait_for_block() )
{
// lock(); // for seeking
if ( seek_pending() )
{
/* FIXME: non-RT-safe IO */
DMESSAGE( "performing seek to frame %lu", (unsigned long)_pending_seek );
_frame = _pending_seek;
_pending_seek = -1;
blocks_ready = 0;
}
if ( ++blocks_ready < _disk_io_blocks )
{
/* wait for more space */
continue;
}
/* reset */
blocks_ready = 0;
read_block( buf, nframes );
// unlock(); // for seeking
/* deinterleave the buffer and stuff it into the per-channel ringbuffers */
const size_t block_size = nframes * sizeof( sample_t );
for ( int i = channels(); i--; )
{
#ifdef AVOID_UNNECESSARY_COPYING
/* deinterleave direcectly into the ringbuffer to avoid
* unnecessary copying */
jack_ringbuffer_data_t rbd[2];
memset( rbd, 0, sizeof( rbd ) );
jack_ringbuffer_get_write_vector( _rb[ i ], rbd );
if ( rbd[ 0 ].len >= block_size )
{
/* it'll all fit in one go */
buffer_deinterleave_one_channel( (sample_t*)rbd[ 0 ].buf, buf, i, channels(), nframes );
}
else if ( rbd[ 0 ].len + rbd[ 1 ].len >= block_size )
{
/* there's enough space in the ringbuffer, but it's not contiguous */
assert( ! ( rbd[ 0 ].len % sizeof( sample_t ) ) );
// assert( ! ( rbd[ 1 ].len % sizeof( sample_t ) ) );
const nframes_t f = rbd[ 0 ].len / sizeof( sample_t );
/* do the first half */
buffer_deinterleave_one_channel( (sample_t*)rbd[ 0 ].buf, buf, i, channels(), f );
assert( rbd[ 1 ].len >= ( nframes - f ) * sizeof( sample_t ) );
/* do the second half */
buffer_deinterleave_one_channel( (sample_t*)rbd[ 1 ].buf, buf + f, i, channels(), nframes - f );
}
else
++_xruns;
jack_ringbuffer_write_advance( _rb[ i ], block_size );
#else
buffer_deinterleave_one_channel( cbuf, buf, i, channels(), nframes );
if ( jack_ringbuffer_write( _rb[ i ], (char*)cbuf, block_size ) < block_size )
++_xruns;
#endif
}
}
DMESSAGE( "playback thread terminating" );
delete[] buf;
#ifndef AVOID_UNNECESSARY_COPYING
delete[] cbuf;
#endif
_terminate = false;
}