Commit 5fc4925f authored by François Cartegnie's avatar François Cartegnie 🤞

demux: mp4: remove/disable dead code

parent 8a0272b8
......@@ -65,7 +65,6 @@ vlc_module_end ()
*****************************************************************************/
static int Demux ( demux_t * );
static int DemuxRef( demux_t *p_demux ){ (void)p_demux; return 0;}
static int DemuxFrg( demux_t * );
static int DemuxAsLeaf( demux_t * );
static int Seek ( demux_t *, mtime_t );
static int Control ( demux_t *, int, va_list );
......@@ -215,6 +214,23 @@ static MP4_Box_t * MP4_GetTrexByTrackID( MP4_Box_t *p_moov, const uint32_t i_id
return p_trex;
}
/**
* Return the track identified by tid
*/
static mp4_track_t *MP4_GetTrackByTrackID( demux_t *p_demux, const uint32_t tid )
{
demux_sys_t *p_sys = p_demux->p_sys;
mp4_track_t *ret = NULL;
for( unsigned i = 0; i < p_sys->i_tracks; i++ )
{
ret = &p_sys->track[i];
if( ret->i_track_ID == tid )
return ret;
}
return NULL;
}
static MP4_Box_t * MP4_GetTrakByTrackID( MP4_Box_t *p_moov, const uint32_t i_id )
{
MP4_Box_t *p_trak = MP4_BoxGet( p_moov, "trak" );
......@@ -261,10 +277,7 @@ static es_out_id_t * MP4_AddTrackES( es_out_t *out, mp4_track_t *p_track )
static inline int64_t MP4_TrackGetDTS( demux_t *p_demux, mp4_track_t *p_track )
{
demux_sys_t *p_sys = p_demux->p_sys;
const mp4_chunk_t *p_chunk;
p_chunk = ( p_track->cchunk ) ? p_track->cchunk /* DemuxFrg */
: &p_track->chunk[p_track->i_chunk];
const mp4_chunk_t *p_chunk = &p_track->chunk[p_track->i_chunk];
unsigned int i_index = 0;
unsigned int i_sample = p_track->i_sample - p_chunk->i_sample_first;
......@@ -312,9 +325,7 @@ static inline bool MP4_TrackGetPTSDelta( demux_t *p_demux, mp4_track_t *p_track,
int64_t *pi_delta )
{
VLC_UNUSED( p_demux );
mp4_chunk_t *ck;
ck = ( p_track->cchunk ) ? p_track->cchunk /* DemuxFrg */
: &p_track->chunk[p_track->i_chunk];
mp4_chunk_t *ck = &p_track->chunk[p_track->i_chunk];
unsigned int i_index = 0;
unsigned int i_sample = p_track->i_sample - ck->i_sample_first;
......@@ -369,16 +380,6 @@ static int AllocateTracks( demux_t *p_demux, unsigned i_tracks )
return VLC_ENOMEM;
p_sys->i_tracks = i_tracks;
if( p_sys->b_fragmented )
{
for( unsigned i = 0; i < i_tracks; i++ )
{
mp4_track_t *p_track = &p_sys->track[i];
p_track->cchunk = calloc( 1, sizeof( mp4_chunk_t ) );
if( unlikely( !p_track->cchunk ) )
return VLC_ENOMEM;
}
}
return VLC_SUCCESS;
}
......@@ -1601,41 +1602,6 @@ static int LeafSeekToPos( demux_t *p_demux, double f )
}
}
static int MP4_frg_Seek( demux_t *p_demux, double f )
{
demux_sys_t *p_sys = p_demux->p_sys;
int64_t i64 = stream_Size( p_demux->s );
if( vlc_stream_Seek( p_demux->s, (int64_t)(i64 * f) ) )
{
return VLC_EGENERIC;
}
else
{
/* update global time */
const uint64_t i_duration = __MAX(p_sys->i_duration, p_sys->i_cumulated_duration);
p_sys->i_time = (uint64_t)(f * (double)i_duration);
p_sys->i_pcr = MP4_GetMoviePTS( p_sys );
for( unsigned i_track = 0; i_track < p_sys->i_tracks; i_track++ )
{
mp4_track_t *tk = &p_sys->track[i_track];
/* We don't want the current chunk to be flushed */
tk->cchunk->i_sample = tk->cchunk->i_sample_count;
/* reset/update some values */
tk->i_sample = tk->i_sample_first = 0;
tk->i_first_dts = p_sys->i_time;
/* We want to discard the current chunk and get the next one at once */
tk->b_has_non_empty_cchunk = false;
}
es_out_Control( p_demux->out, ES_OUT_SET_NEXT_DISPLAY_TIME, p_sys->i_pcr );
return VLC_SUCCESS;
}
}
static bool imageTypeCompatible( const MP4_Box_data_data_t *p_data )
{
return p_data && (
......@@ -1686,8 +1652,6 @@ static int Control( demux_t *p_demux, int i_query, va_list args )
f = (double)va_arg( args, double );
if ( p_demux->pf_demux == DemuxAsLeaf )
return LeafSeekToPos( p_demux, f );
else if ( p_demux->pf_demux == DemuxFrg )
return MP4_frg_Seek( p_demux, f );
else if( p_sys->i_timescale > 0 )
{
i64 = (int64_t)( f * MP4_rescale( p_sys->i_duration,
......@@ -2980,7 +2944,7 @@ static int TrackGotoChunkSample( demux_t *p_demux, mp4_track_t *p_track,
return p_track->b_selected ? VLC_SUCCESS : VLC_EGENERIC;
}
#if 0
static void MP4_TrackRestart( demux_t *p_demux, mp4_track_t *p_track,
MP4_Box_t *p_params_box )
{
......@@ -2993,8 +2957,6 @@ static void MP4_TrackRestart( demux_t *p_demux, mp4_track_t *p_track,
/* Save previous fragmented pos */
uint32_t i_sample_pos_backup = p_track->i_sample;
mp4_chunk_t *cchunk_backup = p_track->cchunk;
p_track->cchunk = NULL;
mtime_t time_backup = p_track->i_time;
uint32_t timescale_backup = p_track->i_timescale;
......@@ -3046,11 +3008,10 @@ static void MP4_TrackRestart( demux_t *p_demux, mp4_track_t *p_track,
es_format_Clean( &fmtbackup );
/* Restore fragmented pos */
p_track->cchunk = cchunk_backup;
p_track->i_sample = i_sample_pos_backup;
p_track->i_time = MP4_rescale( time_backup, timescale_backup, p_track->i_timescale );
}
#endif
/****************************************************************************
* MP4_TrackCreate:
****************************************************************************
......@@ -3334,13 +3295,6 @@ static void DestroyChunk( mp4_chunk_t *ck )
free( ck->p_sample_delta_dts );
free( ck->p_sample_count_pts );
free( ck->p_sample_offset_pts );
if( ck->p_sample_data )
{
for( uint32_t i = 0; i < ck->i_sample_count; i++ )
free( ck->p_sample_data[i] );
free( ck->p_sample_data );
}
free( ck->p_sample_size );
}
......@@ -3363,13 +3317,6 @@ static void MP4_TrackDestroy( demux_t *p_demux, mp4_track_t *p_track )
}
free( p_track->chunk );
if( p_track->cchunk )
{
assert( p_demux->p_sys->b_fragmented );
DestroyChunk( p_track->cchunk );
free( p_track->cchunk );
}
if( !p_track->i_sample_size )
free( p_track->p_sample_size );
......@@ -3792,63 +3739,7 @@ static void MP4_TrackSetELST( demux_t *p_demux, mp4_track_t *tk,
/******************************************************************************
* Here are the functions used for fragmented MP4
*****************************************************************************/
/**
* Return the track identified by tid
*/
static mp4_track_t *MP4_frg_GetTrackByID( demux_t *p_demux, const uint32_t tid )
{
demux_sys_t *p_sys = p_demux->p_sys;
mp4_track_t *ret = NULL;
for( unsigned i = 0; i < p_sys->i_tracks; i++ )
{
ret = &p_sys->track[i];
if( ret->i_track_ID == tid )
return ret;
}
msg_Err( p_demux, "MP4_frg_GetTrack: track %"PRIu32" not found!", tid );
return NULL;
}
static void FlushChunk( demux_t *p_demux, mp4_track_t *tk )
{
msg_Dbg( p_demux, "Flushing chunk for track id %u", tk->i_track_ID );
mp4_chunk_t *ck = tk->cchunk;
while( ck->i_sample < ck->i_sample_count )
{
block_t *p_block;
int64_t i_delta;
if( ck->p_sample_size == NULL || ck->p_sample_data == NULL )
return;
uint32_t sample_size = ck->p_sample_size[ck->i_sample];
assert( sample_size > 0 );
p_block = block_Alloc( sample_size );
if( unlikely( !p_block ) )
return;
uint8_t *src = ck->p_sample_data[ck->i_sample];
memcpy( p_block->p_buffer, src, sample_size );
ck->i_sample++;
/* dts */
p_block->i_dts = VLC_TS_0 + MP4_TrackGetDTS( p_demux, tk );
/* pts */
if( MP4_TrackGetPTSDelta( p_demux, tk, &i_delta ) )
p_block->i_pts = p_block->i_dts + i_delta;
else if( tk->fmt.i_cat != VIDEO_ES )
p_block->i_pts = p_block->i_dts;
else
p_block->i_pts = VLC_TS_INVALID;
MP4_Block_Send( p_demux, tk, p_block );
tk->i_sample++;
}
}
#if 0
/**
* Re-init decoder.
* \Note If we call that function too soon,
......@@ -3870,243 +3761,7 @@ static int ReInitDecoder( demux_t *p_demux, const MP4_Box_t *p_root,
return VLC_SUCCESS;
}
/**
* This function fills a mp4_chunk_t structure from a MP4_Box_t (p_chunk).
* The 'i_tk_id' argument returns the ID of the track the chunk belongs to.
* \note p_chunk usually contains a 'moof' and a 'mdat', and might contain a 'sidx'.
* \return VLC_SUCCESS, VLC_EGENERIC or VLC_ENOMEM.
*/
static int MP4_frg_GetChunk( demux_t *p_demux, MP4_Box_t *p_chunk, unsigned *i_tk_id )
{
MP4_Box_t *p_traf = MP4_BoxGet( p_chunk, "moof/traf" );
if( p_traf == NULL)
{
msg_Warn( p_demux, "no traf box found!" );
return VLC_EGENERIC;
}
MP4_Box_t *p_tfhd = MP4_BoxGet( p_traf, "tfhd" );
if( p_tfhd == NULL)
{
msg_Warn( p_demux, "no tfhd box found!" );
return VLC_EGENERIC;
}
uint32_t i_track_ID = BOXDATA(p_tfhd)->i_track_ID;
*i_tk_id = i_track_ID;
assert( i_track_ID > 0 );
msg_Dbg( p_demux, "GetChunk: track ID is %"PRIu32"", i_track_ID );
mp4_track_t *p_track = MP4_frg_GetTrackByID( p_demux, i_track_ID );
if( !p_track )
return VLC_EGENERIC;
mp4_chunk_t *ret = p_track->cchunk;
if( BOXDATA(p_tfhd)->b_empty )
msg_Warn( p_demux, "No samples in this chunk!" );
/* Usually we read 100 ms of each track. However, suppose we have two tracks,
* Ta and Tv (audio and video). Suppose also that Ta is the first track to be
* read, i.e. we read 100 ms of Ta, then 100 ms of Tv, then 100 ms of Ta,
* and so on. Finally, suppose that we get the chunks the other way around,
* i.e. first a chunk of Tv, then a chunk of Ta, then a chunk of Tv, and so on.
* In that case, it is very likely that at some point, Ta->cchunk or Tv->cchunk
* is not emptied when MP4_frg_GetChunks is called. It is therefore necessary to
* flush it, i.e. send to the decoder the samples not yet sent.
* Note that all the samples to be flushed should worth less than 100 ms,
* (though I did not do the formal proof) and thus this flushing mechanism
* should not cause A/V sync issues, or delays or whatever.
*/
if( ret->i_sample < ret->i_sample_count )
FlushChunk( p_demux, p_track );
if( ret->i_sample_count )
{
DestroyChunk( ret );
memset( ret, 0, sizeof(*ret) );
}
MP4_Box_t *p_trun = MP4_BoxGet( p_traf, "trun");
if( p_trun == NULL)
{
msg_Warn( p_demux, "no trun box found!" );
return VLC_EGENERIC;
}
MP4_Box_data_trun_t *p_trun_data = p_trun->data.p_trun;
ret->i_sample_count = p_trun_data->i_sample_count;
assert( ret->i_sample_count > 0 );
ret->i_sample_description_index = 1; /* seems to be always 1, is it? */
ret->i_sample_first = p_track->i_sample_first;
p_track->i_sample_first += ret->i_sample_count;
ret->i_first_dts = p_track->i_first_dts;
uint32_t default_duration = 0;
uint32_t default_size = 0;
MP4_GetDefaultSizeAndDuration( p_demux, BOXDATA(p_tfhd),
&default_size, &default_duration );
ret->p_sample_count_dts = calloc( ret->i_sample_count, sizeof( uint32_t ) );
ret->p_sample_delta_dts = calloc( ret->i_sample_count, sizeof( uint32_t ) );
if( !ret->p_sample_count_dts || !ret->p_sample_delta_dts )
{
free( ret->p_sample_count_dts );
free( ret->p_sample_delta_dts );
return VLC_ENOMEM;
}
ret->i_entries_dts = ret->i_sample_count;
ret->p_sample_count_pts = calloc( ret->i_sample_count, sizeof( uint32_t ) );
if( !ret->p_sample_count_pts )
return VLC_ENOMEM;
ret->i_entries_pts = ret->i_sample_count;
if( p_trun_data->i_flags & MP4_TRUN_SAMPLE_TIME_OFFSET )
{
ret->p_sample_offset_pts = calloc( ret->i_sample_count, sizeof( int32_t ) );
if( !ret->p_sample_offset_pts )
return VLC_ENOMEM;
}
ret->p_sample_size = calloc( ret->i_sample_count, sizeof( uint32_t ) );
if( !ret->p_sample_size )
return VLC_ENOMEM;
ret->p_sample_data = calloc( ret->i_sample_count, sizeof( uint8_t * ) );
if( !ret->p_sample_data )
return VLC_ENOMEM;
uint32_t dur = 0, i_mdatlen = 0, len;
uint32_t chunk_size = 0;
/* Skip header of mdat */
uint8_t mdat[8];
int i_read = vlc_stream_Read( p_demux->s, &mdat, 8 );
i_mdatlen = GetDWBE( mdat );
if ( i_read < 8 || i_mdatlen < 8 ||
VLC_FOURCC( mdat[4], mdat[5], mdat[6], mdat[7] ) != ATOM_mdat )
return VLC_EGENERIC;
for( uint32_t i = 0; i < ret->i_sample_count; i++)
{
if( p_trun_data->i_flags & MP4_TRUN_SAMPLE_DURATION )
dur = p_trun_data->p_samples[i].i_duration;
else
dur = default_duration;
ret->p_sample_delta_dts[i] = dur;
ret->i_duration += dur;
ret->p_sample_count_dts[i] = ret->p_sample_count_pts[i] = 1;
if( ret->p_sample_offset_pts )
{
if ( p_trun_data->i_version == 1 )
ret->p_sample_offset_pts[i] = (int32_t) p_trun_data->p_samples[i].i_composition_time_offset;
else if( p_trun_data->p_samples[i].i_composition_time_offset < 0xFF000000 )
ret->p_sample_offset_pts[i] = p_trun_data->p_samples[i].i_composition_time_offset;
else /* version 0 with negative */
ret->p_sample_offset_pts[i] = (int32_t) p_trun_data->p_samples[i].i_composition_time_offset;
}
if( p_trun_data->i_flags & MP4_TRUN_SAMPLE_SIZE )
len = ret->p_sample_size[i] = p_trun_data->p_samples[i].i_size;
else
len = ret->p_sample_size[i] = default_size;
if ( chunk_size + len > ( i_mdatlen - 8 ) )
return VLC_EGENERIC;
ret->p_sample_data[i] = malloc( len );
if( ret->p_sample_data[i] == NULL )
return VLC_ENOMEM;
uint32_t i_read = stream_ReadU32( p_demux->s, ret->p_sample_data[i], len );
if( i_read < len )
return VLC_EGENERIC;
chunk_size += len;
}
p_track->i_first_dts = ret->i_duration + ret->i_first_dts;
if( p_track->b_codec_need_restart )
{
ReInitDecoder( p_demux, p_demux->p_sys->p_root, p_track );
p_track->b_codec_need_restart = false;
}
/* Skip if we didn't reach the end of mdat box */
if ( chunk_size < (i_mdatlen - 8) )
stream_ReadU32( p_demux->s, NULL, i_mdatlen - chunk_size - 8 );
p_track->b_has_non_empty_cchunk = true;
return VLC_SUCCESS;
}
/**
* Get the next chunk of the track identified by i_tk_id.
* \Note We don't want to seek all the time, so if the first chunk given by the
* input method doesn't belong to the right track, we don't throw it away,
* and so, in general, this function fetch more than one chunk.
* Not to mention that a new init fragment might be put everywhere
* between two chunks by the input method.
*/
static int MP4_frg_GetChunks( demux_t *p_demux, const unsigned i_tk_id )
{
demux_sys_t *p_sys = p_demux->p_sys;
mp4_track_t *p_track;
for( unsigned i = 0; i < p_sys->i_tracks; i++ )
{
MP4_Box_t *p_chunk = MP4_BoxGetNextChunk( p_demux->s );
if( !p_chunk )
return VLC_EGENERIC;
if( !p_chunk->p_first )
goto MP4_frg_GetChunks_Error;
uint32_t i_type = p_chunk->p_first->i_type;
uint32_t tid = 0;
if( i_type == ATOM_ftyp )
{
MP4_BoxFree( p_sys->p_root );
p_sys->p_root = p_chunk;
MP4_Box_t *p_tkhd = MP4_BoxGet( p_chunk, "/moov/trak[0]/tkhd" );
if( !p_tkhd )
{
msg_Warn( p_demux, "No tkhd found!" );
goto MP4_frg_GetChunks_Error;
}
tid = p_tkhd->data.p_tkhd->i_track_ID;
p_track = MP4_frg_GetTrackByID( p_demux, tid );
if( !p_track )
goto MP4_frg_GetChunks_Error;
p_track->b_codec_need_restart = true;
return MP4_frg_GetChunks( p_demux, i_tk_id );
}
if( MP4_frg_GetChunk( p_demux, p_chunk, &tid ) != VLC_SUCCESS )
goto MP4_frg_GetChunks_Error;
MP4_BoxFree( p_chunk );
if( tid == i_tk_id )
break;
else
continue;
MP4_frg_GetChunks_Error:
MP4_BoxFree( p_chunk );
return VLC_EGENERIC;
}
return VLC_SUCCESS;
}
#endif
static int MP4_frg_TrackSelect( demux_t *p_demux, mp4_track_t *p_track )
{
......@@ -4126,130 +3781,6 @@ static int MP4_frg_TrackSelect( demux_t *p_demux, mp4_track_t *p_track )
return VLC_SUCCESS;
}
/**
* DemuxFrg: read packet and send them to decoders
* \return VLC_DEMUXER_SUCCESS on success, VLC_DEMUXER_EOF on error.
* TODO check for newly selected track
*/
int DemuxFrg( demux_t *p_demux )
{
demux_sys_t *p_sys = p_demux->p_sys;
unsigned i_track;
unsigned i_track_selected;
/* check for newly selected/unselected track */
for( i_track = 0, i_track_selected = 0; i_track < p_sys->i_tracks; i_track++ )
{
mp4_track_t *tk = &p_sys->track[i_track];
bool b;
if( !tk->b_ok || tk->b_chapters_source )
continue;
es_out_Control( p_demux->out, ES_OUT_GET_ES_STATE, tk->p_es, &b );
if( tk->b_selected != b )
msg_Dbg( p_demux, "track %u %s!", tk->i_track_ID, b ? "enabled" : "disabled" );
if( tk->b_selected && !b )
{
MP4_TrackUnselect( p_demux, tk );
}
else if( !tk->b_selected && b)
{
MP4_frg_TrackSelect( p_demux, tk );
}
if( tk->b_selected )
i_track_selected++;
}
if( i_track_selected <= 0 )
{
p_sys->i_time += __MAX( p_sys->i_timescale / 10 , 1 );
if( p_sys->i_timescale > 0 )
{
const uint64_t i_duration = __MAX(p_sys->i_duration, p_sys->i_cumulated_duration);
int64_t i_length = MP4_rescale( i_duration,
p_sys->i_timescale, CLOCK_FREQ );
if( MP4_GetMoviePTS( p_sys ) >= i_length )
return VLC_DEMUXER_EOF;
return VLC_DEMUXER_SUCCESS;
}
msg_Warn( p_demux, "no track selected, exiting..." );
return VLC_DEMUXER_EOF;
}
/* first wait for the good time to read a packet */
es_out_Control( p_demux->out, ES_OUT_SET_PCR, VLC_TS_0 + p_sys->i_pcr );
p_sys->i_pcr = MP4_GetMoviePTS( p_sys );
/* we will read 100ms for each stream so ...*/
p_sys->i_time += __MAX( p_sys->i_timescale / 10, 1 );
for( i_track = 0; i_track < p_sys->i_tracks; i_track++ )
{
mp4_track_t *tk = &p_sys->track[i_track];
if( !tk->b_ok || tk->b_chapters_source || !tk->b_selected )
{
msg_Warn( p_demux, "Skipping track id %u", tk->i_track_ID );
continue;
}
if( !tk->b_has_non_empty_cchunk )
{
if( MP4_frg_GetChunks( p_demux, tk->i_track_ID ) != VLC_SUCCESS )
{
msg_Info( p_demux, "MP4_frg_GetChunks returned error. End of stream?" );
return VLC_DEMUXER_EOF;
}
}
while( MP4_TrackGetDTS( p_demux, tk ) < MP4_GetMoviePTS( p_sys ) )
{
block_t *p_block;
int64_t i_delta;
mp4_chunk_t *ck = tk->cchunk;
if( ck->i_sample >= ck->i_sample_count )
{
msg_Err( p_demux, "sample %"PRIu32" of %"PRIu32"",
ck->i_sample, ck->i_sample_count );
return VLC_DEMUXER_EOF;
}
uint32_t sample_size = ck->p_sample_size[ck->i_sample];
p_block = block_Alloc( sample_size );
uint8_t *src = ck->p_sample_data[ck->i_sample];
memcpy( p_block->p_buffer, src, sample_size );
ck->i_sample++;
if( ck->i_sample == ck->i_sample_count )
tk->b_has_non_empty_cchunk = false;
/* dts */
p_block->i_dts = VLC_TS_0 + MP4_TrackGetDTS( p_demux, tk );
/* pts */
if( MP4_TrackGetPTSDelta( p_demux, tk, &i_delta ) )
p_block->i_pts = p_block->i_dts + i_delta;
else if( tk->fmt.i_cat != VIDEO_ES )
p_block->i_pts = p_block->i_dts;
else
p_block->i_pts = VLC_TS_INVALID;
MP4_Block_Send( p_demux, tk, p_block );
tk->i_sample++;
if( !tk->b_has_non_empty_cchunk )
break;
}
}
return VLC_DEMUXER_SUCCESS;
}
static mtime_t SumFragmentsDurations( demux_t *p_demux )
{
demux_sys_t *p_sys = p_demux->p_sys;
......@@ -5045,7 +4576,7 @@ static int LeafIndexGetMoofPosByTime( demux_t *p_demux, const mtime_t i_target_t
{
int64_t i_pos = -1;
const MP4_Box_data_tfra_t *p_data = BOXDATA(p_tfra);
mp4_track_t *p_track = MP4_frg_GetTrackByID( p_demux, p_data->i_track_ID );
mp4_track_t *p_track = MP4_GetTrackByTrackID( p_demux, p_data->i_track_ID );
if ( p_track && (p_track->fmt.i_cat == AUDIO_ES || p_track->fmt.i_cat == VIDEO_ES) )
{
uint64_t i_track_target_time = MP4_rescale( i_target_time, CLOCK_FREQ, p_track->i_timescale );
......
......@@ -55,7 +55,6 @@ typedef struct
uint32_t *p_sample_count_pts;
int32_t *p_sample_offset_pts; /* pts-dts */
uint8_t **p_sample_data; /* set when b_fragmented is true */
uint32_t *p_sample_size;
/* TODO if needed add pts
but quickly *add* support for edts and seeking */
......@@ -110,7 +109,6 @@ typedef struct
uint32_t i_sample_count;
mp4_chunk_t *chunk; /* always defined for each chunk */
mp4_chunk_t *cchunk; /* current chunk if b_fragmented is true */
/* sample size, p_sample_size defined only if i_sample_size == 0
else i_sample_size is size for all sample */
......@@ -128,8 +126,9 @@ typedef struct