rlm@0: /* Loads "test.spc", skips 5 seconds, saves exact emulator state to "state.bin",
rlm@0: hen records 5 seconds to "first.wav". When run again, loads this state back into
rlm@0: emulator and records 5 seconds to "second.wav". These two wave files should
rlm@0: be identical.
rlm@0: 
rlm@0: Usage: save_state [test.spc]
rlm@0: */
rlm@0: 
rlm@0: #include "snes_spc/spc.h"
rlm@0: 
rlm@0: #include "wave_writer.h"
rlm@0: #include "demo_util.h" /* error(), load_file() */
rlm@0: 
rlm@0: static SNES_SPC* snes_spc;
rlm@0: 
rlm@0: void record_wav( const char* path, int secs )
rlm@0: {
rlm@0: 	/* Start writing wave file */
rlm@0: 	wave_open( spc_sample_rate, path );
rlm@0: 	wave_enable_stereo();
rlm@0: 	while ( wave_sample_count() < secs * spc_sample_rate * 2 )
rlm@0: 	{
rlm@0: 		/* Play into buffer */
rlm@0: 		#define BUF_SIZE 2048
rlm@0: 		short buf [BUF_SIZE];
rlm@0: 		error( spc_play( snes_spc, BUF_SIZE, buf ) );
rlm@0: 		
rlm@0: 		wave_write( buf, BUF_SIZE );
rlm@0: 	}
rlm@0: 	wave_close();
rlm@0: }
rlm@0: 
rlm@0: void state_save( unsigned char** out, void* in, size_t size )
rlm@0: {
rlm@0: 	memcpy( *out, in, size );
rlm@0: 	*out += size;
rlm@0: }
rlm@0: 
rlm@0: void make_save_state( const char* path )
rlm@0: {
rlm@0: 	/* Load SPC */
rlm@0: 	long spc_size;
rlm@0: 	void* spc = load_file( path, &spc_size );
rlm@0: 	error( spc_load_spc( snes_spc, spc, spc_size ) );
rlm@0: 	free( spc );
rlm@0: 	spc_clear_echo( snes_spc );
rlm@0: 	
rlm@0: 	/* Skip several seconds */
rlm@0: 	error( spc_play( snes_spc, 5 * spc_sample_rate * 2, 0 ) );
rlm@0: 	
rlm@0: 	/* Save state to file */
rlm@0: 	{
rlm@0: 		static unsigned char state [spc_state_size]; /* buffer large enough for data */
rlm@0: 		unsigned char* out = state;
rlm@0: 		spc_copy_state( snes_spc, &out, state_save );
rlm@0: 		write_file( "state.bin", state, out - state );
rlm@0: 	}
rlm@0: 	
rlm@0: 	record_wav( "first.wav", 5 );
rlm@0: }
rlm@0: 
rlm@0: void state_load( unsigned char** in, void* out, size_t size )
rlm@0: {
rlm@0: 	memcpy( out, *in, size );
rlm@0: 	*in += size;
rlm@0: }
rlm@0: 
rlm@0: void use_save_state()
rlm@0: {
rlm@0: 	/* Load state into memory */
rlm@0: 	long state_size;
rlm@0: 	unsigned char* state = load_file( "state.bin", &state_size );
rlm@0: 	
rlm@0: 	/* Load into emulator */
rlm@0: 	unsigned char* in = state;
rlm@0: 	spc_copy_state( snes_spc, &in, state_load );
rlm@0: 	assert( in  - state <= state_size ); /* be sure it didn't read past end */
rlm@0: 	
rlm@0: 	record_wav( "second.wav", 5 );
rlm@0: }
rlm@0: 
rlm@0: int file_exists( const char* path )
rlm@0: {
rlm@0: 	FILE* file = fopen( path, "rb" );
rlm@0: 	if ( !file )
rlm@0: 		return 0;
rlm@0: 	
rlm@0: 	fclose( file );
rlm@0: 	return 1;
rlm@0: }
rlm@0: 
rlm@0: int main( int argc, char** argv )
rlm@0: {
rlm@0: 	snes_spc = spc_new();
rlm@0: 	if ( !snes_spc ) error( "Out of memory" );
rlm@0: 	
rlm@0: 	/* Make new state if it doesn't exist, otherwise load it and
rlm@0: 	record to wave file */
rlm@0: 	if ( !file_exists( "state.bin" ) )
rlm@0: 		make_save_state( (argc > 1) ? argv [1] : "test.spc" );
rlm@0: 	else
rlm@0: 		use_save_state();
rlm@0: 	
rlm@0: 	spc_delete( snes_spc );
rlm@0: 	
rlm@0: 	return 0;
rlm@0: }