static libspectrum_error
generalised_data_init( libspectrum_tape_generalised_data_block *block,
libspectrum_tape_generalised_data_block_state *state )
{
state->run = 0;
state->symbols_through_run = 0;
state->edges_through_symbol = 0;
state->current_symbol = 0;
state->symbols_through_stream = 0;
state->current_byte = 0;
state->bits_through_byte = 0;
state->bytes_through_stream = 0;
if( block->pilot_table.symbols_in_block ) {
state->state = LIBSPECTRUM_TAPE_STATE_PILOT;
} else if( block->data_table.symbols_in_block ) {
state->state = LIBSPECTRUM_TAPE_STATE_DATA1;
state->current_byte = block->data[ 0 ];
state->current_symbol = get_generalised_data_symbol( block, state );
} else {
state->state = LIBSPECTRUM_TAPE_STATE_PAUSE;
}
return LIBSPECTRUM_ERROR_NONE;
}
static libspectrum_error
generalised_data_edge( libspectrum_tape_generalised_data_block *block,
libspectrum_tape_generalised_data_block_state *state,
libspectrum_dword *tstates, int *end_of_block,
int *flags )
{
libspectrum_tape_generalised_data_symbol_table *table;
libspectrum_tape_generalised_data_symbol *symbol;
size_t current_symbol;
switch( state->state ) {
case LIBSPECTRUM_TAPE_STATE_PILOT:
table = &( block->pilot_table );
current_symbol = block->pilot_symbols[ state->run ];
symbol = &( table->symbols[ current_symbol ] );
set_tstates_and_flags( symbol, state->edges_through_symbol, tstates,
flags );
state->edges_through_symbol++;
if( state->edges_through_symbol == table->max_pulses ||
symbol->lengths[ state->edges_through_symbol ] == 0 ) {
state->edges_through_symbol = 0;
if( ++state->symbols_through_run == block->pilot_repeats[ state->run ] ) {
state->symbols_through_run = 0;
if( ++state->run == table->symbols_in_block ) {
state->state = LIBSPECTRUM_TAPE_STATE_DATA1;
state->bits_through_byte = 0;
state->bytes_through_stream = 0;
state->symbols_through_stream = 0;
state->current_byte = block->data[ 0 ];
state->current_symbol = get_generalised_data_symbol( block, state );
}
}
}
break;
case LIBSPECTRUM_TAPE_STATE_DATA1:
table = &( block->data_table );
symbol = &( table->symbols[ state->current_symbol ] );
set_tstates_and_flags( symbol, state->edges_through_symbol, tstates,
flags );
state->edges_through_symbol++;
if( state->edges_through_symbol == table->max_pulses ||
symbol->lengths[ state->edges_through_symbol ] == 0 ) {
if( ++state->symbols_through_stream == table->symbols_in_block ) {
state->state = LIBSPECTRUM_TAPE_STATE_PAUSE;
} else {
state->edges_through_symbol = 0;
state->current_symbol = get_generalised_data_symbol( block, state );
}
}
break;
case LIBSPECTRUM_TAPE_STATE_PAUSE:
/* The pause at the end of the block */
*tstates = ( block->pause * 69888 )/20; /* FIXME: should vary with tstates
per frame */
*end_of_block = 1;
break;
default:
libspectrum_print_error( LIBSPECTRUM_ERROR_LOGIC, "%s: unknown state %d",
__func__, state->state );
return LIBSPECTRUM_ERROR_LOGIC;
}
return LIBSPECTRUM_ERROR_NONE;
}
