Added MIDI synthesizer plugin

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@6287 a1c6a512-1295-4272-9138-f99709370657

apps/plugins/midi/midiutil.c

@@ -0,0 +1,262 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ *
+ * Copyright (C) 2005 Stepan Moskovchenko
+ *
+ * All files in this archive are subject to the GNU General Public License.
+ * See the file COPYING in the source tree root for full license agreement.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+
+
+#define BYTE unsigned char
+
+//Data chunk ID types, returned by readID()
+#define ID_UNKNOWN 	-1
+#define ID_MTHD		1
+#define ID_MTRK 	2
+#define ID_EOF  	3
+
+//MIDI Commands
+#define MIDI_NOTE_OFF	128
+#define MIDI_NOTE_ON	144
+#define MIDI_AFTERTOUCH	160
+#define MIDI_CONTROL	176
+#define MIDI_PRGM	192
+#define MIDI_PITCHW	224
+
+
+//MIDI Controllers
+#define CTRL_VOLUME	7
+#define CTRL_BALANCE	8
+#define CTRL_PANNING	10
+#define CHANNEL 	1
+
+
+#define STATE_ATTACK  		1
+#define STATE_DECAY  		2
+#define STATE_SUSTAIN 		3
+#define STATE_RELEASE 		4
+#define STATE_RAMPDOWN		5
+
+#define STATE_LOOPING           7
+#define STATE_NONLOOPING	8
+
+#define LOOP_ENABLED	4
+#define LOOP_PINGPONG   8
+#define LOOP_REVERSE    16
+
+#define LOOPDIR_FORWARD 0
+#define LOOPDIR_REVERSE 1
+
+
+extern struct plugin_api * rb;
+
+
+unsigned char chVol[16];	//Channel volume
+unsigned char chPanLeft[16];	//Channel panning
+unsigned char chPanRight[16];
+unsigned char chPat[16];        //Channel patch
+unsigned char chPW[16];        //Channel pitch wheel, MSB
+
+struct GPatch * gusload(char *);
+struct GPatch * patchSet[128];
+struct GPatch * drumSet[128];
+struct SynthObject voices[MAX_VOICES];
+
+
+
+struct SynthObject
+{
+	int tmp;
+	struct GWaveform * wf;
+	unsigned int delta;
+	unsigned int decay;
+	unsigned int cp;
+	unsigned char state, pstate, loopState, loopDir;
+	unsigned char note, vol, ch, isUsed;
+	int curRate, curOffset, targetOffset;
+	int curPoint;
+};
+
+
+struct Event
+{
+	unsigned int delta;
+	unsigned char status, d1, d2;
+	unsigned int len;
+	unsigned char * evData;
+};
+
+struct Track
+{
+	unsigned int size;
+	unsigned int numEvents;
+	unsigned int delta;	//For sequencing
+	unsigned int pos;	//For sequencing
+	void * dataBlock;
+};
+
+
+struct MIDIfile
+{
+	int  Length;
+
+	//int Format; //We don't really care what type it is
+	unsigned short numTracks;
+	unsigned short div;	//Time division, X ticks per millisecond
+	struct Track * tracks[48];
+	unsigned char patches[128];
+	int numPatches;
+};
+
+void *my_malloc(int size);
+
+void *alloc(int size)
+{
+	static char *offset = NULL;
+	static int totalSize = 0;
+	char *ret;
+
+	if (offset == NULL)
+	{
+		offset = rb->plugin_get_audio_buffer(&totalSize);
+	}
+
+	if (size + 4 > totalSize)
+	{
+		return NULL;
+	}
+
+	ret = offset + 4;
+	*((unsigned int *)offset) = size;
+
+	offset += size + 4;
+	totalSize -= size + 4;
+	return ret;
+}
+
+void *ralloc(char *offset, int len)
+{
+	int size;
+	char *ret;
+
+	if (offset == NULL)
+	{
+		return alloc(len);
+	}
+
+	size = *((unsigned int *)offset - 4);
+
+	if (size >= 0x02000000)
+	{
+		return NULL;
+	}
+
+	ret = alloc(len);
+
+	if (len < size)
+	{
+		rb->memcpy(ret, offset, len);
+	}
+	else
+	{
+		rb->memcpy(ret, offset, size);
+		rb->memset(ret, 0, len - size);
+	}
+
+	return ret;
+}
+
+
+void * allocate(int size)
+{
+	return alloc(size);
+}
+
+void sendEvent(struct Event * ev);
+int tick(struct MIDIfile * mf);
+inline void setPoint(struct SynthObject * so, int pt);
+struct Event * getEvent(struct Track * tr, int evNum);
+
+unsigned char readChar(int file)
+{
+	char buf[2];
+	rb->read(file, &buf, 1);
+	return buf[0];
+}
+
+unsigned char * readData(int file, int len)
+{
+	unsigned char * dat = allocate(len);
+	rb->read(file, dat, len);
+	return dat;
+}
+
+int eof(int fd)
+{
+	int curPos = rb->lseek(fd, 0, SEEK_CUR);
+
+	int size = rb->lseek(fd, 0, SEEK_END);
+
+	rb->lseek(fd, curPos, SEEK_SET);
+	return size+1 == rb->lseek(fd, 0, SEEK_CUR);
+}
+
+void printf(char *fmt, ...) {}
+
+//#define my_malloc(a) malloc(a)
+
+
+void *audio_bufferbase;
+void *audio_bufferpointer;
+unsigned int audio_buffer_free;
+
+
+
+
+void *my_malloc(int size)
+{
+
+    void *alloc;
+
+    if (!audio_bufferbase)
+    {
+        audio_bufferbase = audio_bufferpointer
+            = rb->plugin_get_audio_buffer(&audio_buffer_free);
+#if MEM <= 8 && !defined(SIMULATOR)
+
+        if ((unsigned)(ovl_start_addr - (unsigned char *)audio_bufferbase)
+            < audio_buffer_free)
+            audio_buffer_free = ovl_start_addr - (unsigned char *)audio_bufferbase;
+#endif
+    }
+    if (size + 4 > audio_buffer_free)
+        return 0;
+    alloc = audio_bufferpointer;
+    audio_bufferpointer += size + 4;
+    audio_buffer_free -= size + 4;
+    return alloc;
+}
+
+void setmallocpos(void *pointer)
+{
+    audio_bufferpointer = pointer;
+    audio_buffer_free = audio_bufferpointer - audio_bufferbase;
+}
+
+void exit(int code)
+{
+}
+
+void free(void * ptr)
+{
+}