1 files changed, 480 insertions, 0 deletions

diff --git a/lib/rbcodec/codecs/libgme/sgc_emu.c b/lib/rbcodec/codecs/libgme/sgc_emu.c
new file mode 100644
index 0000000000..267f2c9271
--- /dev/null
+++ b/lib/rbcodec/codecs/libgme/sgc_emu.c
@@ -0,0 +1,480 @@
+// Game_Music_Emu 0.6-pre. http://www.slack.net/~ant/
+
+#include "sgc_emu.h"
+
+/* Copyright (C) 2009 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 aint 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"
+
+int const osc_count = sms_osc_count + fm_apu_osc_count;
+
+const char gme_wrong_file_type [] = "Wrong file type for this emulator";
+
+static void clear_track_vars( struct Sgc_Emu* this )
+{
+        this->current_track    = -1;
+        track_stop( &this->track_filter );
+}
+
+void Sgc_init( struct Sgc_Emu* this )
+{
+        assert( offsetof (struct header_t,copyright [32]) == header_size );
+        
+        this->sample_rate = 0;
+        this->mute_mask_  = 0;
+        this->tempo       = (int)FP_ONE_TEMPO;
+        this->gain        = (int)FP_ONE_GAIN;
+        
+        // defaults
+        this->tfilter = *track_get_setup( &this->track_filter );
+        this->tfilter.max_initial = 2;
+        this->tfilter.lookahead   = 6;
+        this->track_filter.silence_ignored_ = false;
+
+        Sms_apu_init( &this->apu );
+        Fm_apu_create( &this->fm_apu );
+
+        Rom_init( &this->rom, 0x4000 );
+        Z80_init( &this->cpu );
+
+        Sound_set_gain( this, (int)(FP_ONE_GAIN*1.2) );
+        
+        // Unload
+        this->voice_count = 0;
+        this->voice_types = 0;
+        clear_track_vars( this );
+}
+
+// Setup
+
+blargg_err_t Sgc_load_mem( struct Sgc_Emu* this, const void* data, long size )
+{
+        RETURN_ERR( Rom_load( &this->rom, data, size, header_size, &this->header, 0 ) );
+        
+        if ( !valid_tag( &this->header ) )
+                return gme_wrong_file_type;
+        
+        /* if ( header.vers != 1 )
+                warning( "Unknown file version" ); */
+        
+        /* if ( header.system > 2 )
+                warning( "Unknown system" ); */
+        
+        addr_t load_addr = get_le16( this->header.load_addr );
+        /* if ( load_addr < 0x400 )
+                set_warning( "Invalid load address" ); */
+        
+        Rom_set_addr( &this->rom, load_addr );
+        this->play_period = clock_rate( this ) / 60;
+        
+        if ( sega_mapping( this ) && Fm_apu_supported() )
+                RETURN_ERR( Fm_apu_init( &this->fm_apu, clock_rate( this ), clock_rate( this ) / 72 ) );
+        
+        this->m3u.size = 0;
+        this->track_count = this->header.song_count;
+        this->voice_count =  sega_mapping( this ) ? osc_count : sms_osc_count;
+        static int const types [sms_osc_count + fm_apu_osc_count] = {
+                wave_type+1, wave_type+2, wave_type+3, mixed_type+1, mixed_type+2
+        };
+        this->voice_types = types;
+        
+        Sms_apu_volume( &this->apu, this->gain );
+        Fm_apu_volume( &this->fm_apu, this->gain );
+
+        // Setup buffer
+        this->clock_rate_ = clock_rate( this );
+        Buffer_clock_rate( &this->stereo_buf, clock_rate( this ) );
+        RETURN_ERR( Buffer_set_channel_count( &this->stereo_buf, this->voice_count, this->voice_types ) );
+        this->buf_changed_count = Buffer_channels_changed_count( &this->stereo_buf );
+
+        Sound_set_tempo( this, this->tempo );
+        Sound_mute_voices( this, this->mute_mask_ );
+        return 0;
+}
+
+static void Sound_set_voice( struct Sgc_Emu* this, int i, struct Blip_Buffer* c, struct Blip_Buffer* l, struct Blip_Buffer* r )
+{
+        if ( i < sms_osc_count )
+                Sms_apu_set_output( &this->apu, i, c, l, r );
+        else
+                Fm_apu_set_output( &this->fm_apu, c );
+}
+
+static blargg_err_t run_clocks( struct Sgc_Emu* this, blip_time_t* duration, int msec )
+{
+#if defined(ROCKBOX)
+        (void) msec;
+#endif
+
+        cpu_time_t t = *duration;
+        while ( Z80_time( &this->cpu ) < t )
+        {
+                cpu_time_t next = min( t, this->next_play );
+                if ( run_cpu( this, next ) )
+                {
+                        /* warning( "Unsupported CPU instruction" ); */
+                        Z80_set_time( &this->cpu, next );
+                }
+                
+                if ( this->cpu.r.pc == this->idle_addr )
+                        Z80_set_time( &this->cpu, next );
+                
+                if ( Z80_time( &this->cpu ) >= this->next_play )
+                {
+                        this->next_play += this->play_period;
+                        if ( this->cpu.r.pc == this->idle_addr )
+                                jsr( this, this->header.play_addr );
+                }
+        }
+        
+        this->next_play -= t;
+        check( this->next_play >= 0 );
+        Z80_adjust_time( &this->cpu, -t );
+        
+        Sms_apu_end_frame( &this->apu, t );
+        if ( sega_mapping( this ) && this->fm_accessed )
+        {
+                if ( Fm_apu_supported() )
+                        Fm_apu_end_frame( &this->fm_apu, t );
+                /* else
+                        warning( "FM sound not supported" ); */
+        }
+
+        return 0;
+}
+
+// Emulation
+
+void cpu_out( struct Sgc_Emu* this, cpu_time_t time, addr_t addr, int data )
+{
+        int port = addr & 0xFF;
+        
+        if ( sega_mapping( this ) )
+        {
+                switch ( port )
+                {
+                case 0x06:
+                        Sms_apu_write_ggstereo( &this->apu, time, data );
+                        return;
+                
+                case 0x7E:
+                case 0x7F:
+                        Sms_apu_write_data( &this->apu, time, data ); /* dprintf( "$7E<-%02X\n", data ); */
+                        return;
+                
+                case 0xF0:
+                        this->fm_accessed = true;
+                        if ( Fm_apu_supported() )
+                                Fm_apu_write_addr( &this->fm_apu, data );//, dprintf( "$F0<-%02X\n", data );
+                        return;
+                
+                case 0xF1:
+                        this->fm_accessed = true;
+                        if ( Fm_apu_supported() )
+                                Fm_apu_write_data( &this->fm_apu, time, data );//, dprintf( "$F1<-%02X\n", data );
+                        return;
+                }
+        }
+        else if ( port >= 0xE0 )
+        {
+                Sms_apu_write_data( &this->apu, time, data );
+                return;
+        }
+}
+
+void jsr( struct Sgc_Emu* this, byte addr [2] )
+{
+        *Z80_write( &this->cpu, --this->cpu.r.sp ) = this->idle_addr >> 8;
+        *Z80_write( &this->cpu, --this->cpu.r.sp ) = this->idle_addr & 0xFF;
+        this->cpu.r.pc = get_le16( addr );
+}
+
+static void set_bank( struct Sgc_Emu* this, int bank, void const* data )
+{
+        //dprintf( "map bank %d to %p\n", bank, (byte*) data - rom.at_addr( 0 ) );
+        Z80_map_mem( &this->cpu, bank * this->rom.bank_size, this->rom.bank_size, this->unmapped_write, data );
+}
+
+void cpu_write( struct Sgc_Emu* this, addr_t addr, int data )
+{
+        if ( (addr ^ 0xFFFC) > 3 || !sega_mapping( this ) )
+        {
+                *Z80_write( &this->cpu, addr ) = data;
+                return;
+        }
+        
+        switch ( addr )
+        {
+        case 0xFFFC:
+                Z80_map_mem_rw( &this->cpu, 2 * this->rom.bank_size, this->rom.bank_size, this->ram2 );
+                if ( data & 0x08 )
+                        break;
+                
+                this->bank2 = this->ram2;
+                // FALL THROUGH
+        
+        case 0xFFFF: {
+                bool rom_mapped = (Z80_read( &this->cpu, 2 * this->rom.bank_size ) == this->bank2);
+                this->bank2 = Rom_at_addr( &this->rom, data * this->rom.bank_size );
+                if ( rom_mapped )
+                        set_bank( this, 2, this->bank2 );
+                break;
+        }
+                
+        case 0xFFFD:
+                set_bank( this, 0, Rom_at_addr( &this->rom, data * this->rom.bank_size ) );
+                break;
+        
+        case 0xFFFE:
+                set_bank( this, 1, Rom_at_addr( &this->rom, data * this->rom.bank_size ) );
+                break;
+        }
+}
+
+blargg_err_t Sgc_set_sample_rate( struct Sgc_Emu* this, int rate )
+{
+        require( !this->sample_rate ); // sample rate can't be changed once set
+        Buffer_init( &this->stereo_buf );
+        Buffer_set_sample_rate( &this->stereo_buf, rate, 1000 / 20 );
+
+        // Set buffer bass
+        Buffer_bass_freq( &this->stereo_buf, 80 );
+
+        this->sample_rate = rate;
+        RETURN_ERR( track_init( &this->track_filter, this ) );
+        this->tfilter.max_silence = 6 * stereo * this->sample_rate;
+        return 0;
+}
+
+void Sound_mute_voice( struct Sgc_Emu* this, int index, bool mute )
+{
+        require( (unsigned) index < (unsigned) this->voice_count );
+        int bit = 1 << index;
+        int mask = this->mute_mask_ | bit;
+        if ( !mute )
+                mask ^= bit;
+        Sound_mute_voices( this, mask );
+}
+
+void Sound_mute_voices( struct Sgc_Emu* this, int mask )
+{
+        require( this->sample_rate ); // sample rate must be set first
+        this->mute_mask_ = mask;
+        
+        int i;
+        for ( i = this->voice_count; i--; )
+        {
+                if ( mask & (1 << i) )
+                {
+                        Sound_set_voice( this, i, 0, 0, 0 );
+                }
+                else
+                {
+                        struct channel_t ch = Buffer_channel( &this->stereo_buf, i );
+                        assert( (ch.center && ch.left && ch.right) ||
+                                        (!ch.center && !ch.left && !ch.right) ); // all or nothing
+                        Sound_set_voice( this, i, ch.center, ch.left, ch.right );
+                }
+        }
+}
+
+void Sound_set_tempo( struct Sgc_Emu* this, int t )
+{
+        require( this->sample_rate ); // sample rate must be set first
+        int const min = (int)(FP_ONE_TEMPO*0.02);
+        int const max = (int)(FP_ONE_TEMPO*4.00);
+        if ( t < min ) t = min;
+        if ( t > max ) t = max;
+        this->tempo = t;
+
+        this->play_period = (int) ((clock_rate( this ) * FP_ONE_TEMPO) / (this->header.rate ? 50 : 60) / t);
+}
+
+blargg_err_t Sgc_start_track( struct Sgc_Emu* this, int track )
+{
+        clear_track_vars( this );
+        
+        // Remap track if playlist available
+        if ( this->m3u.size > 0 ) {
+                struct entry_t* e = &this->m3u.entries[track];
+                track = e->track;
+        }
+        
+        this->current_track = track;
+        
+        if ( sega_mapping( this ) )
+        {
+                Sms_apu_reset( &this->apu, 0, 0 );
+                Fm_apu_reset( &this->fm_apu );
+                this->fm_accessed = false;
+        }
+        else
+        {
+                Sms_apu_reset( &this->apu, 0x0003, 15 );
+        }
+        
+        memset( this->ram , 0, sizeof this->ram );
+        memset( this->ram2, 0, sizeof this->ram2 );
+        memset( this->vectors, 0xFF, sizeof this->vectors );
+        Z80_reset( &this->cpu, this->unmapped_write, this->rom.unmapped );
+        
+        if ( sega_mapping( this ) )
+        {
+                this->vectors_addr = 0x10000 - page_size;
+                this->idle_addr = this->vectors_addr;
+                int i;
+                for ( i = 1; i < 8; ++i )
+                {
+                        this->vectors [i*8 + 0] = 0xC3; // JP addr
+                        this->vectors [i*8 + 1] = this->header.rst_addrs [i - 1] & 0xff;
+                        this->vectors [i*8 + 2] = this->header.rst_addrs [i - 1] >> 8;
+                }
+                
+                Z80_map_mem_rw( &this->cpu, 0xC000, 0x2000, this->ram );
+                Z80_map_mem( &this->cpu, this->vectors_addr, page_size, this->unmapped_write, this->vectors );
+                
+                this->bank2 = NULL;
+                for ( i = 0; i < 4; ++i )
+                        cpu_write( this, 0xFFFC + i, this->header.mapping [i] );
+        }
+        else
+        {
+                if ( !this->coleco_bios )
+                        return "Coleco BIOS not set"; /* BLARGG_ERR( BLARGG_ERR_CALLER, "Coleco BIOS not set" ); */
+                
+                this->vectors_addr = 0;
+                Z80_map_mem( &this->cpu, 0, 0x2000, this->unmapped_write, this->coleco_bios );
+                int i;
+                for ( i = 0; i < 8; ++i )
+                        Z80_map_mem_rw( &this->cpu, 0x6000 + i*0x400, 0x400, this->ram );
+                
+                this->idle_addr = 0x2000;
+                Z80_map_mem( &this->cpu, 0x2000, page_size, this->unmapped_write, this->vectors );
+                
+                for ( i = 0; i < 0x8000 / this->rom.bank_size; ++i )
+                {
+                        int addr = 0x8000 + i*this->rom.bank_size;
+                        Z80_map_mem( &this->cpu, addr, this->rom.bank_size, this->unmapped_write, Rom_at_addr( &this->rom, addr ) );
+                }
+        }
+        
+        this->cpu.r.sp  = get_le16( this->header.stack_ptr );
+        this->cpu.r.b.a = track;
+        this->next_play = this->play_period;
+
+        jsr( this, this->header.init_addr );
+
+        Buffer_clear( &this->stereo_buf );
+
+        // convert filter times to samples
+        struct setup_t s = this->tfilter;
+        s.max_initial *= this->sample_rate * stereo;
+        #ifdef GME_DISABLE_SILENCE_LOOKAHEAD
+                s.lookahead = 1;
+        #endif
+        track_setup( &this->track_filter, &s );
+        
+        return track_start( &this->track_filter );
+}
+
+// Tell/Seek
+
+static int msec_to_samples( int msec, int sample_rate )
+{
+        int sec = msec / 1000;
+        msec -= sec * 1000;
+        return (sec * sample_rate + msec * sample_rate / 1000) * stereo;
+}
+
+int Track_tell( struct Sgc_Emu* this )
+{
+        int rate = this->sample_rate * stereo;
+        int sec = track_sample_count( &this->track_filter ) / rate;
+        return sec * 1000 + (track_sample_count( &this->track_filter ) - sec * rate) * 1000 / rate;
+}
+
+blargg_err_t Track_seek( struct Sgc_Emu* this, int msec )
+{
+        int time = msec_to_samples( msec, this->sample_rate );
+        if ( time < track_sample_count( &this->track_filter ) )
+        RETURN_ERR( Sgc_start_track( this, this->current_track ) );
+        return Track_skip( this, time - track_sample_count( &this->track_filter ) );
+}
+
+blargg_err_t Track_skip( struct Sgc_Emu* this, int count )
+{
+        require( this->current_track >= 0 ); // start_track() must have been called already
+        return track_skip( &this->track_filter, count );
+}
+
+blargg_err_t skip_( void* emu, int count )
+{
+        struct Sgc_Emu* this = (struct Sgc_Emu*) emu;
+        
+        // for long skip, mute sound
+        const int threshold = 32768;
+        if ( count > threshold )
+        {
+                int saved_mute = this->mute_mask_;
+                Sound_mute_voices( this, ~0 );
+
+                int n = count - threshold/2;
+                n &= ~(2048-1); // round to multiple of 2048
+                count -= n;
+                RETURN_ERR( skippy_( &this->track_filter, n ) );
+
+                Sound_mute_voices( this, saved_mute );
+        }
+
+        return skippy_( &this->track_filter, count );
+}
+
+void Track_set_fade( struct Sgc_Emu* this, int start_msec, int length_msec )
+{
+        track_set_fade( &this->track_filter, msec_to_samples( start_msec, this->sample_rate ),
+                length_msec * this->sample_rate / (1000 / stereo) );
+}
+
+blargg_err_t Sgc_play( struct Sgc_Emu* this, int out_count, sample_t* out )
+{
+        require( this->current_track >= 0 );
+        require( out_count % stereo == 0 );
+        return track_play( &this->track_filter, out_count, out );
+}
+
+blargg_err_t play_( void* emu, int count, sample_t out [] )
+{
+        struct Sgc_Emu* this = (struct Sgc_Emu*) emu;
+        
+        int remain = count;
+        while ( remain )
+        {
+                Buffer_disable_immediate_removal( &this->stereo_buf );
+                remain -= Buffer_read_samples( &this->stereo_buf, &out [count - remain], remain );
+                if ( remain )
+                {
+                        if ( this->buf_changed_count != Buffer_channels_changed_count( &this->stereo_buf ) )
+                        {
+                                this->buf_changed_count = Buffer_channels_changed_count( &this->stereo_buf );
+                                
+                                // Remute voices
+                                Sound_mute_voices( this, this->mute_mask_ );
+                        }
+                        int msec = Buffer_length( &this->stereo_buf );
+                        blip_time_t clocks_emulated = msec * this->clock_rate_ / 1000 - 100;
+                        RETURN_ERR( run_clocks( this, &clocks_emulated, msec ) );
+                        assert( clocks_emulated );
+                        Buffer_end_frame( &this->stereo_buf, clocks_emulated );
+                }
+        }
+        return 0;
+}