// Game_Music_Emu 0.5.2. http://www.slack.net/~ant/ #include "Spc_Emu.h" #include "blargg_endian.h" #include <stdlib.h> #include <string.h> /* Copyright (C) 2004-2006 Shay Green. This module is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This module is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this module; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "blargg_source.h" Spc_Emu::Spc_Emu() { set_type( gme_spc_type ); static const char* const names [Snes_Spc::voice_count] = { "DSP 1", "DSP 2", "DSP 3", "DSP 4", "DSP 5", "DSP 6", "DSP 7", "DSP 8" }; set_voice_names( names ); set_gain( 1.4 ); } Spc_Emu::~Spc_Emu() { } // Track info long const trailer_offset = 0x10200; byte const* Spc_Emu::trailer() const { return &file_data [min( file_size, trailer_offset )]; } long Spc_Emu::trailer_size() const { return max( 0L, file_size - trailer_offset ); } static void get_spc_xid6( byte const* begin, long size, track_info_t* out ) { // header byte const* end = begin + size; if ( size < 8 || memcmp( begin, "xid6", 4 ) ) { check( false ); return; } long info_size = get_le32( begin + 4 ); byte const* in = begin + 8; if ( end - in > info_size ) { dprintf( "Extra data after SPC xid6 info\n" ); end = in + info_size; } int year = 0; char copyright [256 + 5]; int copyright_len = 0; int const year_len = 5; while ( end - in >= 4 ) { // header int id = in [0]; int data = in [3] * 0x100 + in [2]; int type = in [1]; int len = type ? data : 0; in += 4; if ( len > end - in ) { check( false ); break; // block goes past end of data } // handle specific block types char* field = 0; switch ( id ) { case 0x01: field = out->song; break; case 0x02: field = out->game; break; case 0x03: field = out->author; break; case 0x04: field = out->dumper; break; case 0x07: field = out->comment; break; case 0x14: year = data; break; //case 0x30: // intro length // Many SPCs have intro length set wrong for looped tracks, making it useless /* case 0x30: check( len == 4 ); if ( len >= 4 ) { out->intro_length = get_le32( in ) / 64; if ( out->length > 0 ) { long loop = out->length - out->intro_length; if ( loop >= 2000 ) out->loop_length = loop; } } break; */ case 0x13: copyright_len = min( len, (int) sizeof copyright - year_len ); memcpy( ©right [year_len], in, copyright_len ); break; default: if ( id < 0x01 || (id > 0x07 && id < 0x10) || (id > 0x14 && id < 0x30) || id > 0x36 ) dprintf( "Unknown SPC xid6 block: %X\n", (int) id ); break; } if ( field ) { check( type == 1 ); Gme_File::copy_field_( field, (char const*) in, len ); } // skip to next block in += len; // blocks are supposed to be 4-byte aligned with zero-padding... byte const* unaligned = in; while ( (in - begin) & 3 && in < end ) { if ( *in++ != 0 ) { // ...but some files have no padding in = unaligned; dprintf( "SPC info tag wasn't properly padded to align\n" ); break; } } } char* p = ©right [year_len]; if ( year ) { *--p = ' '; for ( int n = 4; n--; ) { *--p = char (year % 10 + '0'); year /= 10; } copyright_len += year_len; } if ( copyright_len ) Gme_File::copy_field_( out->copyright, p, copyright_len ); check( in == end ); } static void get_spc_info( Spc_Emu::header_t const& h, byte const* xid6, long xid6_size, track_info_t* out ) { // decode length (can be in text or binary format, sometimes ambiguous ugh) long len_secs = 0; for ( int i = 0; i < 3; i++ ) { unsigned n = h.len_secs [i] - '0'; if ( n > 9 ) { // ignore single-digit text lengths // (except if author field is present and begins at offset 1, ugh) if ( i == 1 && (h.author [0] || !h.author [1]) ) len_secs = 0; break; } len_secs *= 10; len_secs += n; } if ( !len_secs || len_secs > 0x1FFF ) len_secs = get_le16( h.len_secs ); if ( len_secs < 0x1FFF ) out->length = len_secs * 1000; int offset = (h.author [0] < ' ' || unsigned (h.author [0] - '0') <= 9); Gme_File::copy_field_( out->author, &h.author [offset], sizeof h.author - offset ); GME_COPY_FIELD( h, out, song ); GME_COPY_FIELD( h, out, game ); GME_COPY_FIELD( h, out, dumper ); GME_COPY_FIELD( h, out, comment ); if ( xid6_size ) get_spc_xid6( xid6, xid6_size, out ); } blargg_err_t Spc_Emu::track_info_( track_info_t* out, int ) const { get_spc_info( header(), trailer(), trailer_size(), out ); return 0; } static blargg_err_t check_spc_header( void const* header ) { if ( memcmp( header, "SNES-SPC700 Sound File Data", 27 ) ) return gme_wrong_file_type; return 0; } struct Spc_File : Gme_Info_ { Spc_Emu::header_t header; blargg_vector<byte> xid6; Spc_File() { set_type( gme_spc_type ); } blargg_err_t load_( Data_Reader& in ) { long file_size = in.remain(); if ( file_size < Snes_Spc::spc_min_file_size ) return gme_wrong_file_type; RETURN_ERR( in.read( &header, Spc_Emu::header_size ) ); RETURN_ERR( check_spc_header( header.tag ) ); long const xid6_offset = 0x10200; long xid6_size = file_size - xid6_offset; if ( xid6_size > 0 ) { RETURN_ERR( xid6.resize( xid6_size ) ); RETURN_ERR( in.skip( xid6_offset - Spc_Emu::header_size ) ); RETURN_ERR( in.read( xid6.begin(), (long)xid6.size() ) ); } return 0; } blargg_err_t track_info_( track_info_t* out, int ) const { get_spc_info( header, xid6.begin(), (long)xid6.size(), out ); return 0; } }; static Music_Emu* new_spc_emu () { return BLARGG_NEW Spc_Emu ; } static Music_Emu* new_spc_file() { return BLARGG_NEW Spc_File; } static gme_type_t_ const gme_spc_type_ = { "Super Nintendo", 1, &new_spc_emu, &new_spc_file, "SPC", 0 }; gme_type_t const gme_spc_type = &gme_spc_type_; // Setup blargg_err_t Spc_Emu::set_sample_rate_( long sample_rate ) { RETURN_ERR( apu.init() ); apu.set_gain( (int) (gain() * Snes_Spc::gain_unit) ); if ( sample_rate != native_sample_rate ) { RETURN_ERR( resampler.buffer_size( native_sample_rate / 20 * 2 ) ); resampler.time_ratio( (double) native_sample_rate / sample_rate, 0.9965 ); } return 0; } void Spc_Emu::mute_voices_( int m ) { Music_Emu::mute_voices_( m ); apu.mute_voices( m ); } blargg_err_t Spc_Emu::load_mem_( byte const* in, long size ) { assert( offsetof (header_t,unused2 [46]) == header_size ); file_data = in; file_size = size; set_voice_count( Snes_Spc::voice_count ); if ( size < Snes_Spc::spc_min_file_size ) return gme_wrong_file_type; return check_spc_header( in ); } // Emulation void Spc_Emu::set_tempo_( double t ) { apu.set_tempo( (int) (t * Snes_Spc::tempo_unit) ); } blargg_err_t Spc_Emu::start_track_( int track ) { RETURN_ERR( Music_Emu::start_track_( track ) ); resampler.clear(); RETURN_ERR( apu.load_spc( file_data, file_size ) ); apu.clear_echo(); return 0; } blargg_err_t Spc_Emu::skip_( long count ) { if ( sample_rate() != native_sample_rate ) { count = long (count * resampler.ratio()) & ~1; count -= resampler.skip_input( count ); } // TODO: shouldn't skip be adjusted for the 64 samples read afterwards? if ( count > 0 ) RETURN_ERR( apu.skip( count ) ); // eliminate pop due to resampler const int resampler_latency = 64; sample_t buf [resampler_latency]; return play_( resampler_latency, buf ); } blargg_err_t Spc_Emu::play_( long count, sample_t* out ) { if ( sample_rate() == native_sample_rate ) return apu.play( count, out ); long remain = count; while ( remain > 0 ) { remain -= resampler.read( &out [count - remain], remain ); if ( remain > 0 ) { long n = resampler.max_write(); RETURN_ERR( apu.play( n, resampler.buffer() ) ); resampler.write( n ); } } check( remain == 0 ); return 0; }