org.red5.io.matroska.ParserUtils Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the "License") + you may not use this file except in compliance with the
* License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under
* the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing
* permissions and limitations under the License.
*/
package org.red5.io.matroska;
import static org.red5.io.matroska.VINT.MASK_BYTE_1;
import static org.red5.io.matroska.VINT.MASK_BYTE_2;
import static org.red5.io.matroska.VINT.MASK_BYTE_3;
import static org.red5.io.matroska.VINT.MASK_BYTE_4;
import static org.red5.io.matroska.VINT.MASK_BYTE_8;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.util.ArrayList;
import org.red5.io.matroska.dtd.CompoundTag;
import org.red5.io.matroska.dtd.Tag;
import org.red5.io.matroska.dtd.TagFactory;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class ParserUtils {
private static Logger log = LoggerFactory.getLogger(ParserUtils.class);
public static final int BIT_IN_BYTE = 8;
/**
* method used to parse : int, uint and date
*
* @param inputStream
* - stream to get value
* @param size
* - size of the value in bytes
* @return - parsed value as long
* @throws IOException
* - in case of IO error
*/
public static long parseInteger(InputStream inputStream, final int size) throws IOException {
log.debug("parseInteger inputStream: {} size: {}", inputStream, size);
byte[] buffer = new byte[size];
int numberOfReadsBytes = inputStream.read(buffer, 0, size);
log.debug("numberOfReadsBytes: {}", numberOfReadsBytes);
//assert numberOfReadsBytes == size;
long value = buffer[0] & (long) 0xff;
for (int i = 1; i < size; ++i) {
value = (value << BIT_IN_BYTE) | ((long) buffer[i] & (long) 0xff);
}
return value;
}
/**
* method used to parse string
*
* @param inputStream
* - stream to get value
* @param size
* - size of the value in bytes
* @return - parsed value as {@link String}
* @throws IOException
* - in case of IO error
*/
public static String parseString(InputStream inputStream, final int size) throws IOException {
if (0 == size) {
return "";
}
byte[] buffer = new byte[size];
int numberOfReadsBytes = inputStream.read(buffer, 0, size);
assert numberOfReadsBytes == size;
return new String(buffer, "UTF-8");
}
/**
* method used to parse float and double
*
* @param inputStream
* - stream to get value
* @param size
* - size of the value in bytes
* @return - parsed value as double
* @throws IOException
* - in case of IO error
*/
public static double parseFloat(InputStream inputStream, final int size) throws IOException {
byte[] buffer = new byte[size];
int numberOfReadsBytes = inputStream.read(buffer, 0, size);
assert numberOfReadsBytes == size;
ByteBuffer byteBuffer = ByteBuffer.wrap(buffer).order(ByteOrder.BIG_ENDIAN);
if (8 == size) {
return byteBuffer.getDouble();
}
return byteBuffer.getFloat();
}
/**
* method used to parse subelements of {@link CompoundTag}
*
* @param inputStream
* - stream to get value
* @param size
* - size of the value in bytes
* @return - parsed tag
* @throws IOException
* - in case of IO error
* @throws ConverterException
* - in case of any conversion exception
*/
public static ArrayList parseMasterElement(InputStream inputStream, final int size) throws IOException, ConverterException {
byte bufferForSubElements[] = new byte[size];
int readOfBytes = inputStream.read(bufferForSubElements, 0, size);
assert readOfBytes == size;
ArrayList subElements = new ArrayList();
ByteArrayInputStream inputStreamForSubElements = new ByteArrayInputStream(bufferForSubElements);
while (0 != inputStreamForSubElements.available()) {
subElements.add(parseTag(inputStreamForSubElements));
}
return subElements;
}
/**
* method to parse byte array
*
* @param inputStream
* - stream to get value
* @param size
* - size of the value in bytes
* @return - parsed value as array of bytes
* @throws IOException
* - in case of IO error
*/
public static byte[] parseBinary(InputStream inputStream, final int size) throws IOException {
byte value[] = new byte[size];
int i = value.length;
while (i != 0) {
i -= inputStream.read(value, value.length - i, i);
}
return value;
}
/**
* method to parse {@link VINT}
*
* @param inputStream
* - stream to get value
* @return - parsed value
* @throws IOException
* - in case of IO error
*/
public static VINT readVINT(InputStream inputStream) throws IOException {
byte[] vint;
int fb = inputStream.read();
int read = 0;
assert fb > 0;
int len = (fb >> 4);
long mask = MASK_BYTE_4;
if (len >= 0b1000) {
read = 0;
mask = MASK_BYTE_1;
vint = new byte[1];
} else if (len >= 0b0100) {
mask = MASK_BYTE_2;
vint = new byte[2];
read = inputStream.read(vint, 1, 1);
assert read == 1;
} else if (len >= 0b0010) {
mask = MASK_BYTE_3;
vint = new byte[3];
read = inputStream.read(vint, 1, 2);
assert read == 2;
} else if (len >= 0b0001) {
vint = new byte[4];
read = inputStream.read(vint, 1, 3);
assert read == 3;
} else {
mask = MASK_BYTE_8;
vint = new byte[8];
read = inputStream.read(vint, 1, 7);
assert read == 7;
}
vint[0] = (byte) fb;
long binaryV = 0;
for (int i = 0; i < vint.length; ++i) {
binaryV += (0x00FF & vint[i]);
if (i != vint.length - 1) {
binaryV <<= BIT_IN_BYTE;
}
}
return new VINT(binaryV, (byte) (read + 1), mask & binaryV);
}
/**
* parsing tag by matroska specification matroska spec
*
* tag = VINT id, VINT size, data
*
* @param inputStream
* - stream to get value
* @return tag, without parsing tag data, because it delegate to an tag itself
* @throws IOException
* - in case of IO error
* @throws ConverterException
* - in case of any conversion exception
*/
public static Tag parseTag(InputStream inputStream) throws IOException, ConverterException {
VINT id = readVINT(inputStream);
VINT size = readVINT(inputStream);
return TagFactory.createTag(id, size, inputStream);
}
/**
* method to encode long as byte array of given size
*
* @param val
* - value to encode
* @param size
* - size
* @return - byte array
*/
public static byte[] getBytes(long val, long size) {
byte[] res = new byte[(int) size];
long bv = val;
for (int i = (int) size - 1; i >= 0; --i) {
res[i] = (byte) (bv & 0xFF);
bv >>= BIT_IN_BYTE;
}
return res;
}
/**
* method to skip given amount of bytes in stream
*
* @param size
* - size to skip
* @param input
* - input stream to process
* @throws IOException
* - in case of IO error
*/
public static void skip(long size, InputStream input) throws IOException {
while (size > 0) {
size -= input.skip(size);
}
}
}
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