/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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 General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package com.sun.media.sound;
import java.io.DataInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.IOException;
import java.io.EOFException;
import java.io.BufferedInputStream;
import java.net.URL;
import javax.sound.midi.MidiFileFormat;
import javax.sound.midi.InvalidMidiDataException;
import javax.sound.midi.MetaMessage;
import javax.sound.midi.MidiEvent;
import javax.sound.midi.MidiMessage;
import javax.sound.midi.Sequence;
import javax.sound.midi.SysexMessage;
import javax.sound.midi.Track;
import javax.sound.midi.spi.MidiFileReader;
/**
* MIDI file reader.
*
* @author Kara Kytle
* @author Jan Borgersen
* @author Florian Bomers
*/
public final class StandardMidiFileReader extends MidiFileReader {
private static final int MThd_MAGIC = 0x4d546864; // 'MThd'
private static final int bisBufferSize = 1024; // buffer size in buffered input streams
public MidiFileFormat getMidiFileFormat(InputStream stream) throws InvalidMidiDataException, IOException {
return getMidiFileFormatFromStream(stream, MidiFileFormat.UNKNOWN_LENGTH, null);
}
// $$fb 2002-04-17: part of fix for 4635286: MidiSystem.getMidiFileFormat() returns format having invalid length
private MidiFileFormat getMidiFileFormatFromStream(InputStream stream, int fileLength, SMFParser smfParser) throws InvalidMidiDataException, IOException {
int maxReadLength = 16;
int duration = MidiFileFormat.UNKNOWN_LENGTH;
DataInputStream dis;
if (stream instanceof DataInputStream) {
dis = (DataInputStream) stream;
} else {
dis = new DataInputStream(stream);
}
if (smfParser == null) {
dis.mark(maxReadLength);
} else {
smfParser.stream = dis;
}
int type;
int numtracks;
float divisionType;
int resolution;
try {
int magic = dis.readInt();
if( !(magic == MThd_MAGIC) ) {
// not MIDI
throw new InvalidMidiDataException("not a valid MIDI file");
}
// read header length
int bytesRemaining = dis.readInt() - 6;
type = dis.readShort();
numtracks = dis.readShort();
int timing = dis.readShort();
// decipher the timing code
if (timing > 0) {
// tempo based timing. value is ticks per beat.
divisionType = Sequence.PPQ;
resolution = timing;
} else {
// SMPTE based timing. first decipher the frame code.
int frameCode = -1 * (timing >> 8);
switch(frameCode) {
case 24:
divisionType = Sequence.SMPTE_24;
break;
case 25:
divisionType = Sequence.SMPTE_25;
break;
case 29:
divisionType = Sequence.SMPTE_30DROP;
break;
case 30:
divisionType = Sequence.SMPTE_30;
break;
default:
throw new InvalidMidiDataException("Unknown frame code: " + frameCode);
}
// now determine the timing resolution in ticks per frame.
resolution = timing & 0xFF;
}
if (smfParser != null) {
// remainder of this chunk
dis.skip(bytesRemaining);
smfParser.tracks = numtracks;
}
} finally {
// if only reading the file format, reset the stream
if (smfParser == null) {
dis.reset();
}
}
MidiFileFormat format = new MidiFileFormat(type, divisionType, resolution, fileLength, duration);
return format;
}
public MidiFileFormat getMidiFileFormat(URL url) throws InvalidMidiDataException, IOException {
InputStream urlStream = url.openStream(); // throws IOException
BufferedInputStream bis = new BufferedInputStream( urlStream, bisBufferSize );
MidiFileFormat fileFormat = null;
try {
fileFormat = getMidiFileFormat( bis ); // throws InvalidMidiDataException
} finally {
bis.close();
}
return fileFormat;
}
public MidiFileFormat getMidiFileFormat(File file) throws InvalidMidiDataException, IOException {
FileInputStream fis = new FileInputStream(file); // throws IOException
BufferedInputStream bis = new BufferedInputStream(fis, bisBufferSize);
// $$fb 2002-04-17: part of fix for 4635286: MidiSystem.getMidiFileFormat() returns format having invalid length
long length = file.length();
if (length > Integer.MAX_VALUE) {
length = MidiFileFormat.UNKNOWN_LENGTH;
}
MidiFileFormat fileFormat = null;
try {
fileFormat = getMidiFileFormatFromStream(bis, (int) length, null);
} finally {
bis.close();
}
return fileFormat;
}
public Sequence getSequence(InputStream stream) throws InvalidMidiDataException, IOException {
SMFParser smfParser = new SMFParser();
MidiFileFormat format = getMidiFileFormatFromStream(stream,
MidiFileFormat.UNKNOWN_LENGTH,
smfParser);
// must be MIDI Type 0 or Type 1
if ((format.getType() != 0) && (format.getType() != 1)) {
throw new InvalidMidiDataException("Invalid or unsupported file type: " + format.getType());
}
// construct the sequence object
Sequence sequence = new Sequence(format.getDivisionType(), format.getResolution());
// for each track, go to the beginning and read the track events
for (int i = 0; i < smfParser.tracks; i++) {
if (smfParser.nextTrack()) {
smfParser.readTrack(sequence.createTrack());
} else {
break;
}
}
return sequence;
}
public Sequence getSequence(URL url) throws InvalidMidiDataException, IOException {
InputStream is = url.openStream(); // throws IOException
is = new BufferedInputStream(is, bisBufferSize);
Sequence seq = null;
try {
seq = getSequence(is);
} finally {
is.close();
}
return seq;
}
public Sequence getSequence(File file) throws InvalidMidiDataException, IOException {
InputStream is = new FileInputStream(file); // throws IOException
is = new BufferedInputStream(is, bisBufferSize);
Sequence seq = null;
try {
seq = getSequence(is);
} finally {
is.close();
}
return seq;
}
}
//=============================================================================================================
/**
* State variables during parsing of a MIDI file
*/
final class SMFParser {
private static final int MTrk_MAGIC = 0x4d54726b; // 'MTrk'
// set to true to not allow corrupt MIDI files tombe loaded
private static final boolean STRICT_PARSER = false;
private static final boolean DEBUG = false;
int tracks; // number of tracks
DataInputStream stream; // the stream to read from
private int trackLength = 0; // remaining length in track
private byte[] trackData = null;
private int pos = 0;
SMFParser() {
}
private int readUnsigned() throws IOException {
return trackData[pos++] & 0xFF;
}
private void read(byte[] data) throws IOException {
System.arraycopy(trackData, pos, data, 0, data.length);
pos += data.length;
}
private long readVarInt() throws IOException {
long value = 0; // the variable-lengh int value
int currentByte = 0;
do {
currentByte = trackData[pos++] & 0xFF;
value = (value << 7) + (currentByte & 0x7F);
} while ((currentByte & 0x80) != 0);
return value;
}
private int readIntFromStream() throws IOException {
try {
return stream.readInt();
} catch (EOFException eof) {
throw new EOFException("invalid MIDI file");
}
}
boolean nextTrack() throws IOException, InvalidMidiDataException {
int magic;
trackLength = 0;
do {
// $$fb 2003-08-20: fix for 4910986: MIDI file parser breaks up on http connection
if (stream.skipBytes(trackLength) != trackLength) {
if (!STRICT_PARSER) {
return false;
}
throw new EOFException("invalid MIDI file");
}
magic = readIntFromStream();
trackLength = readIntFromStream();
} while (magic != MTrk_MAGIC);
if (!STRICT_PARSER) {
if (trackLength < 0) {
return false;
}
}
// now read track in a byte array
trackData = new byte[trackLength];
try {
// $$fb 2003-08-20: fix for 4910986: MIDI file parser breaks up on http connection
stream.readFully(trackData);
} catch (EOFException eof) {
if (!STRICT_PARSER) {
return false;
}
throw new EOFException("invalid MIDI file");
}
pos = 0;
return true;
}
private boolean trackFinished() {
return pos >= trackLength;
}
void readTrack(Track track) throws IOException, InvalidMidiDataException {
try {
// reset current tick to 0
long tick = 0;
// reset current status byte to 0 (invalid value).
// this should cause us to throw an InvalidMidiDataException if we don't
// get a valid status byte from the beginning of the track.
int status = 0;
boolean endOfTrackFound = false;
while (!trackFinished() && !endOfTrackFound) {
MidiMessage message;
int data1 = -1; // initialize to invalid value
int data2 = 0;
// each event has a tick delay and then the event data.
// first read the delay (a variable-length int) and update our tick value
tick += readVarInt();
// check for new status
int byteValue = readUnsigned();
if (byteValue >= 0x80) {
status = byteValue;
} else {
data1 = byteValue;
}
switch (status & 0xF0) {
case 0x80:
case 0x90:
case 0xA0:
case 0xB0:
case 0xE0:
// two data bytes
if (data1 == -1) {
data1 = readUnsigned();
}
data2 = readUnsigned();
message = new FastShortMessage(status | (data1 << 8) | (data2 << 16));
break;
case 0xC0:
case 0xD0:
// one data byte
if (data1 == -1) {
data1 = readUnsigned();
}
message = new FastShortMessage(status | (data1 << 8));
break;
case 0xF0:
// sys-ex or meta
switch(status) {
case 0xF0:
case 0xF7:
// sys ex
int sysexLength = (int) readVarInt();
byte[] sysexData = new byte[sysexLength];
read(sysexData);
SysexMessage sysexMessage = new SysexMessage();
sysexMessage.setMessage(status, sysexData, sysexLength);
message = sysexMessage;
break;
case 0xFF:
// meta
int metaType = readUnsigned();
int metaLength = (int) readVarInt();
byte[] metaData = new byte[metaLength];
read(metaData);
MetaMessage metaMessage = new MetaMessage();
metaMessage.setMessage(metaType, metaData, metaLength);
message = metaMessage;
if (metaType == 0x2F) {
// end of track means it!
endOfTrackFound = true;
}
break;
default:
throw new InvalidMidiDataException("Invalid status byte: " + status);
} // switch sys-ex or meta
break;
default:
throw new InvalidMidiDataException("Invalid status byte: " + status);
} // switch
track.add(new MidiEvent(message, tick));
} // while
} catch (ArrayIndexOutOfBoundsException e) {
if (DEBUG) e.printStackTrace();
// fix for 4834374
throw new EOFException("invalid MIDI file");
}
}
}