cd: switch to CD drive emu code from genplus

same license, much cleaner code

pico/cd/cdd.h

@@ -0,0 +1,98 @@
+/***************************************************************************************
+ *  Genesis Plus
+ *  CD drive processor & CD-DA fader
+ *
+ *  Copyright (C) 2012-2013  Eke-Eke (Genesis Plus GX)
+ *
+ *  Redistribution and use of this code or any derivative works are permitted
+ *  provided that the following conditions are met:
+ *
+ *   - Redistributions may not be sold, nor may they be used in a commercial
+ *     product or activity.
+ *
+ *   - Redistributions that are modified from the original source must include the
+ *     complete source code, including the source code for all components used by a
+ *     binary built from the modified sources. However, as a special exception, the
+ *     source code distributed need not include anything that is normally distributed
+ *     (in either source or binary form) with the major components (compiler, kernel,
+ *     and so on) of the operating system on which the executable runs, unless that
+ *     component itself accompanies the executable.
+ *
+ *   - Redistributions must reproduce the above copyright notice, this list of
+ *     conditions and the following disclaimer in the documentation and/or other
+ *     materials provided with the distribution.
+ *
+ *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ *  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ *  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ *  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ *  POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************************/
+#ifndef _HW_CDD_
+#define _HW_CDD_
+
+#ifdef USE_LIBTREMOR
+#include "tremor/ivorbisfile.h"
+#endif
+
+/* CDD status */
+#define NO_DISC  0x00
+#define CD_PLAY  0x01
+#define CD_SEEK  0x02
+#define CD_SCAN  0x03
+#define CD_READY 0x04
+#define CD_OPEN  0x05 /* similar to 0x0E ? */
+#define CD_STOP  0x09
+#define CD_END   0x0C
+
+/* CD blocks scanning speed */
+#define CD_SCAN_SPEED 30
+
+#define CD_MAX_TRACKS 100
+
+/* CD track */
+typedef struct
+{
+  void *fd;
+#ifdef USE_LIBTREMOR
+  OggVorbis_File vf;
+#endif
+  int offset;
+  int start;
+  int end;
+} track_t; 
+
+/* CD TOC */
+typedef struct
+{
+  int end;
+  int last;
+  track_t tracks[CD_MAX_TRACKS];
+} toc_t; 
+
+/* CDD hardware */
+typedef struct
+{
+  uint32 cycles;
+  uint32 latency;
+  int loaded;
+  int index;
+  int lba;
+  int scanOffset;
+  int volume;
+  uint8 status;
+  uint16 sectorSize;
+  toc_t toc;
+  int16 audio[2];
+} cdd_t; 
+
+extern cdd_t cdd;
+
+#endif