1 files changed, 204 insertions, 0 deletions

diff --git a/apps/codecs/libgme/gbs_emu.h b/apps/codecs/libgme/gbs_emu.h
new file mode 100644
index 0000000000..c107264f9f
--- /dev/null
+++ b/apps/codecs/libgme/gbs_emu.h
@@ -0,0 +1,204 @@
+// Nintendo Game Boy GBS music file emulator
+
+// Game_Music_Emu 0.5.2
+#ifndef GBS_EMU_H
+#define GBS_EMU_H
+
+#include "rom_data.h"
+#include "multi_buffer.h"
+#include "gb_apu.h"
+#include "gb_cpu.h"
+#include "m3u_playlist.h"
+
+/* typedef uint8_t byte; */
+typedef short sample_t;
+
+enum { joypad_addr = 0xFF00 };
+enum { ram_addr = 0xA000 };
+enum { hi_page = 0xFF00 - ram_addr };
+enum { io_base = 0xFF00 };
+enum { buf_size = 2048 };
+
+// Selects which sound hardware to use. AGB hardware is cleaner than the
+// others. Doesn't take effect until next start_track().
+enum sound_t {
+        sound_dmg = mode_dmg,   // Game Boy monochrome
+        sound_cgb = mode_cgb,   // Game Boy Color
+        sound_agb = mode_agb,   // Game Boy Advance
+        sound_gbs               // Use DMG/CGB based on GBS (default)
+};
+
+// GBS file header
+enum { header_size = 112 };
+struct header_t
+{
+        char tag [3];
+        byte vers;
+        byte track_count;
+        byte first_track;
+        byte load_addr [2];
+        byte init_addr [2];
+        byte play_addr [2];
+        byte stack_ptr [2];
+        byte timer_modulo;
+        byte timer_mode;
+        char game [32];
+        char author [32];
+        char copyright [32];
+};
+
+struct Gbs_Emu {
+        enum sound_t sound_hardware;
+        
+        int tempo;
+        
+        // timer
+        blip_time_t cpu_time;
+        blip_time_t end_time;
+        blip_time_t play_period;
+        blip_time_t next_play;
+
+        // Sound 
+        long clock_rate_;
+        long sample_rate_;
+        unsigned buf_changed_count;
+        int voice_count_;
+        double gain_;
+        double tempo_;
+        
+        // track-specific
+        byte track_count;
+        volatile bool track_ended;
+        int current_track_;
+        blargg_long out_time;  // number of samples played since start of track
+        blargg_long emu_time;  // number of samples emulator has generated since start of track
+        bool emu_track_ended_; // emulator has reached end of track
+        
+        // fading
+        blargg_long fade_start;
+        int fade_step;
+        
+        // silence detection
+        // Disable automatic end-of-track detection and skipping of silence at beginning
+        bool ignore_silence;
+
+        int max_initial_silence;
+        int mute_mask_;
+        int silence_lookahead; // speed to run emulator when looking ahead for silence
+        long silence_time;     // number of samples where most recent silence began
+        long silence_count;    // number of samples of silence to play before using buf
+        long buf_remain;       // number of samples left in silence buffer
+        
+        // Larger items at the end
+        // Header for currently loaded file
+        struct header_t header;
+        
+        // M3u Playlist
+        struct M3u_Playlist m3u;
+        
+        struct Gb_Apu apu;
+        struct Gb_Cpu cpu;
+        struct Stereo_Buffer stereo_buf;
+        
+        sample_t buf [buf_size];
+        
+        // rom & ram
+        struct Rom_Data rom; 
+        byte ram [0x4000 + 0x2000 + cpu_padding];
+};
+
+
+// Basic functionality
+// Initializes Gbs_Emu structure
+void Gbs_init( struct Gbs_Emu* this );
+
+// Stops (clear) Gbs_Emu structure
+void Gbs_stop( struct Gbs_Emu* this );
+
+// Loads a file from memory
+blargg_err_t Gbs_load( struct Gbs_Emu* this, void* data, long size );
+
+// Set output sample rate. Must be called only once before loading file.
+blargg_err_t Gbs_set_sample_rate( struct Gbs_Emu* this, long sample_rate );
+
+// Start a track, where 0 is the first track. Also clears warning string.
+blargg_err_t Gbs_start_track( struct Gbs_Emu* this, int );
+
+// Generate 'count' samples info 'buf'. Output is in stereo. Any emulation
+// errors set warning string, and major errors also end track.
+blargg_err_t Gbs_play( struct Gbs_Emu* this, long count, sample_t* buf ) ICODE_ATTR;
+
+// Track status/control
+// Number of milliseconds (1000 msec = 1 second) played since beginning of track
+long Track_tell( struct Gbs_Emu* this );
+
+// Seek to new time in track. Seeking backwards or far forward can take a while.
+blargg_err_t Track_seek( struct Gbs_Emu* this, long msec );
+
+// Skip n samples
+blargg_err_t Track_skip( struct Gbs_Emu* this, long n );
+
+// Set start time and length of track fade out. Once fade ends track_ended() returns
+// true. Fade time can be changed while track is playing.
+void Track_set_fade( struct Gbs_Emu* this, long start_msec, long length_msec );
+
+// Get track length in milliseconds
+static inline long Track_get_length( struct Gbs_Emu* this, int n )
+{
+        long length = 120 * 1000;  /* 2 minutes */ 
+        if ( (this->m3u.size > 0) && (n < this->m3u.size) ) {
+                struct entry_t* entry = &this->m3u.entries [n];
+                length = entry->length;
+        } 
+        
+        return length;
+}
+
+
+// Sound customization
+// Adjust song tempo, where 1.0 = normal, 0.5 = half speed, 2.0 = double speed.
+// Track length as returned by track_info() assumes a tempo of 1.0.
+void Sound_set_tempo( struct Gbs_Emu* this, double );
+
+// Mute/unmute voice i, where voice 0 is first voice
+void Sound_mute_voice( struct Gbs_Emu* this, int index, bool mute );
+
+// Set muting state of all voices at once using a bit mask, where -1 mutes them all,
+// 0 unmutes them all, 0x01 mutes just the first voice, etc.
+void Sound_mute_voices( struct Gbs_Emu* this, int mask );
+
+// Change overall output amplitude, where 1.0 results in minimal clamping.
+// Must be called before set_sample_rate().
+static inline void Sound_set_gain( struct Gbs_Emu* this, double g )
+{
+        assert( !this->sample_rate_ ); // you must set gain before setting sample rate
+        this->gain_ = g;
+}
+
+
+// Emulation (You shouldn't touch these)
+
+blargg_err_t Run_clocks( struct Gbs_Emu* this, blip_time_t duration ) ICODE_ATTR;
+void Set_bank( struct Gbs_Emu* this, int ) ICODE_ATTR;
+void Update_timer( struct Gbs_Emu* this ) ICODE_ATTR;
+
+// Runs CPU until time becomes >= 0
+void Run_cpu( struct Gbs_Emu* this ) ICODE_ATTR;
+
+// Reads/writes memory and I/O
+int  Read_mem( struct Gbs_Emu* this, addr_t addr ) ICODE_ATTR;
+void Write_mem( struct Gbs_Emu* this, addr_t addr, int data ) ICODE_ATTR;
+
+// Current time
+static inline blip_time_t Time( struct Gbs_Emu* this ) 
+{
+        return Cpu_time( &this->cpu ) + this->end_time; 
+}
+
+void Jsr_then_stop( struct Gbs_Emu* this, byte const [] ) ICODE_ATTR;
+void Write_io_inline( struct Gbs_Emu* this, int offset, int data, int base ) ICODE_ATTR;
+void Write_io_( struct Gbs_Emu* this, int offset, int data ) ICODE_ATTR;
+int  Read_io(  struct Gbs_Emu* this, int offset ) ICODE_ATTR;
+void Write_io( struct Gbs_Emu* this, int offset, int data ) ICODE_ATTR;
+
+#endif