/*
* 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.apache.catalina.connector;
import java.io.IOException;
import java.io.Reader;
import java.nio.Buffer;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.charset.Charset;
import java.security.AccessController;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import javax.servlet.ReadListener;
import org.apache.catalina.security.SecurityUtil;
import org.apache.coyote.ActionCode;
import org.apache.coyote.ContainerThreadMarker;
import org.apache.coyote.Request;
import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
import org.apache.tomcat.util.buf.B2CConverter;
import org.apache.tomcat.util.buf.ByteChunk;
import org.apache.tomcat.util.collections.SynchronizedStack;
import org.apache.tomcat.util.net.ApplicationBufferHandler;
import org.apache.tomcat.util.res.StringManager;
/**
* The buffer used by Tomcat request. This is a derivative of the Tomcat 3.3
* OutputBuffer, adapted to handle input instead of output. This allows
* complete recycling of the facade objects (the ServletInputStream and the
* BufferedReader).
*
* @author Remy Maucherat
*/
public class InputBuffer extends Reader
implements ByteChunk.ByteInputChannel, ApplicationBufferHandler {
/**
* The string manager for this package.
*/
protected static final StringManager sm = StringManager.getManager(InputBuffer.class);
private static final Log log = LogFactory.getLog(InputBuffer.class);
public static final int DEFAULT_BUFFER_SIZE = 8 * 1024;
// The buffer can be used for byte[] and char[] reading
// ( this is needed to support ServletInputStream and BufferedReader )
public final int INITIAL_STATE = 0;
public final int CHAR_STATE = 1;
public final int BYTE_STATE = 2;
/**
* Encoder cache.
*/
private static final Map<Charset, SynchronizedStack<B2CConverter>> encoders = new ConcurrentHashMap<>();
// ----------------------------------------------------- Instance Variables
/**
* The byte buffer.
*/
private ByteBuffer bb;
/**
* The char buffer.
*/
private CharBuffer cb;
/**
* State of the output buffer.
*/
private int state = 0;
/**
* Flag which indicates if the input buffer is closed.
*/
private boolean closed = false;
/**
* Current byte to char converter.
*/
protected B2CConverter conv;
/**
* Associated Coyote request.
*/
private Request coyoteRequest;
/**
* Buffer position.
*/
private int markPos = -1;
/**
* Char buffer limit.
*/
private int readLimit;
/**
* Buffer size.
*/
private final int size;
// ----------------------------------------------------------- Constructors
/**
* Default constructor. Allocate the buffer with the default buffer size.
*/
public InputBuffer() {
this(DEFAULT_BUFFER_SIZE);
}
/**
* Alternate constructor which allows specifying the initial buffer size.
*
* @param size Buffer size to use
*/
public InputBuffer(int size) {
this.size = size;
bb = ByteBuffer.allocate(size);
clear(bb);
cb = CharBuffer.allocate(size);
clear(cb);
readLimit = size;
}
// ------------------------------------------------------------- Properties
/**
* Associated Coyote request.
*
* @param coyoteRequest Associated Coyote request
*/
public void setRequest(Request coyoteRequest) {
this.coyoteRequest = coyoteRequest;
}
// --------------------------------------------------------- Public Methods
/**
* Recycle the output buffer.
*/
public void recycle() {
state = INITIAL_STATE;
// If usage of mark made the buffer too big, reallocate it
if (cb.capacity() > size) {
cb = CharBuffer.allocate(size);
clear(cb);
} else {
clear(cb);
}
readLimit = size;
markPos = -1;
clear(bb);
closed = false;
if (conv != null) {
conv.recycle();
encoders.get(conv.getCharset()).push(conv);
conv = null;
}
}
/**
* Close the input buffer.
*
* @throws IOException An underlying IOException occurred
*/
@Override
public void close() throws IOException {
closed = true;
}
public int available() {
int available = 0;
if (state == BYTE_STATE) {
available = bb.remaining();
} else if (state == CHAR_STATE) {
available = cb.remaining();
}
if (available == 0) {
coyoteRequest.action(ActionCode.AVAILABLE,
Boolean.valueOf(coyoteRequest.getReadListener() != null));
available = (coyoteRequest.getAvailable() > 0) ? 1 : 0;
}
return available;
}
public void setReadListener(ReadListener listener) {
coyoteRequest.setReadListener(listener);
// The container is responsible for the first call to
// listener.onDataAvailable(). If isReady() returns true, the container
// needs to call listener.onDataAvailable() from a new thread. If
// isReady() returns false, the socket will be registered for read and
// the container will call listener.onDataAvailable() once data arrives.
// Must call isFinished() first as a call to isReady() if the request
// has been finished will register the socket for read interest and that
// is not required.
if (!coyoteRequest.isFinished() && isReady()) {
coyoteRequest.action(ActionCode.DISPATCH_READ, null);
if (!ContainerThreadMarker.isContainerThread()) {
// Not on a container thread so need to execute the dispatch
coyoteRequest.action(ActionCode.DISPATCH_EXECUTE, null);
}
}
}
public boolean isFinished() {
int available = 0;
if (state == BYTE_STATE) {
available = bb.remaining();
} else if (state == CHAR_STATE) {
available = cb.remaining();
}
if (available > 0) {
return false;
} else {
return coyoteRequest.isFinished();
}
}
public boolean isReady() {
if (coyoteRequest.getReadListener() == null) {
if (log.isDebugEnabled()) {
log.debug(sm.getString("inputBuffer.requiresNonBlocking"));
}
return false;
}
if (isFinished()) {
// If this is a non-container thread, need to trigger a read
// which will eventually lead to a call to onAllDataRead() via a
// container thread.
if (!ContainerThreadMarker.isContainerThread()) {
coyoteRequest.action(ActionCode.DISPATCH_READ, null);
coyoteRequest.action(ActionCode.DISPATCH_EXECUTE, null);
}
return false;
}
boolean result = available() > 0;
if (!result) {
coyoteRequest.action(ActionCode.NB_READ_INTEREST, null);
}
return result;
}
boolean isBlocking() {
return coyoteRequest.getReadListener() == null;
}
// ------------------------------------------------- Bytes Handling Methods
/**
* Reads new bytes in the byte chunk.
*
* @throws IOException An underlying IOException occurred
*/
@Override
public int realReadBytes() throws IOException {
if (closed) {
return -1;
}
if (coyoteRequest == null) {
return -1;
}
if (state == INITIAL_STATE) {
state = BYTE_STATE;
}
int result = coyoteRequest.doRead(this);
return result;
}
public int readByte() throws IOException {
if (closed) {
throw new IOException(sm.getString("inputBuffer.streamClosed"));
}
if (checkByteBufferEof()) {
return -1;
}
return bb.get() & 0xFF;
}
public int read(byte[] b, int off, int len) throws IOException {
if (closed) {
throw new IOException(sm.getString("inputBuffer.streamClosed"));
}
if (checkByteBufferEof()) {
return -1;
}
int n = Math.min(len, bb.remaining());
bb.get(b, off, n);
return n;
}
/**
* Transfers bytes from the buffer to the specified ByteBuffer. After the
* operation the position of the ByteBuffer will be returned to the one
* before the operation, the limit will be the position incremented by
* the number of the transfered bytes.
*
* @param to the ByteBuffer into which bytes are to be written.
* @return an integer specifying the actual number of bytes read, or -1 if
* the end of the stream is reached
* @throws IOException if an input or output exception has occurred
*/
public int read(ByteBuffer to) throws IOException {
if (closed) {
throw new IOException(sm.getString("inputBuffer.streamClosed"));
}
if (checkByteBufferEof()) {
return -1;
}
int n = Math.min(to.remaining(), bb.remaining());
int orgLimit = bb.limit();
bb.limit(bb.position() + n);
to.put(bb);
bb.limit(orgLimit);
to.limit(to.position()).position(to.position() - n);
return n;
}
// ------------------------------------------------- Chars Handling Methods
public int realReadChars() throws IOException {
checkConverter();
boolean eof = false;
if (bb.remaining() <= 0) {
int nRead = realReadBytes();
if (nRead < 0) {
eof = true;
}
}
if (markPos == -1) {
clear(cb);
} else {
// Make sure there's enough space in the worst case
makeSpace(bb.remaining());
if ((cb.capacity() - cb.limit()) == 0 && bb.remaining() != 0) {
// We went over the limit
clear(cb);
markPos = -1;
}
}
state = CHAR_STATE;
conv.convert(bb, cb, this, eof);
if (cb.remaining() == 0 && eof) {
return -1;
} else {
return cb.remaining();
}
}
@Override
public int read() throws IOException {
if (closed) {
throw new IOException(sm.getString("inputBuffer.streamClosed"));
}
if (checkCharBufferEof()) {
return -1;
}
return cb.get();
}
@Override
public int read(char[] cbuf) throws IOException {
if (closed) {
throw new IOException(sm.getString("inputBuffer.streamClosed"));
}
return read(cbuf, 0, cbuf.length);
}
@Override
public int read(char[] cbuf, int off, int len) throws IOException {
if (closed) {
throw new IOException(sm.getString("inputBuffer.streamClosed"));
}
if (checkCharBufferEof()) {
return -1;
}
int n = Math.min(len, cb.remaining());
cb.get(cbuf, off, n);
return n;
}
@Override
public long skip(long n) throws IOException {
if (closed) {
throw new IOException(sm.getString("inputBuffer.streamClosed"));
}
if (n < 0) {
throw new IllegalArgumentException();
}
long nRead = 0;
while (nRead < n) {
if (cb.remaining() >= n) {
cb.position(cb.position() + (int) n);
nRead = n;
} else {
nRead += cb.remaining();
cb.position(cb.limit());
int nb = realReadChars();
if (nb < 0) {
break;
}
}
}
return nRead;
}
@Override
public boolean ready() throws IOException {
if (closed) {
throw new IOException(sm.getString("inputBuffer.streamClosed"));
}
if (state == INITIAL_STATE) {
state = CHAR_STATE;
}
return (available() > 0);
}
@Override
public boolean markSupported() {
return true;
}
@Override
public void mark(int readAheadLimit) throws IOException {
if (closed) {
throw new IOException(sm.getString("inputBuffer.streamClosed"));
}
if (cb.remaining() <= 0) {
clear(cb);
} else {
if ((cb.capacity() > (2 * size)) && (cb.remaining()) < (cb.position())) {
cb.compact();
cb.flip();
}
}
readLimit = cb.position() + readAheadLimit + size;
markPos = cb.position();
}
@Override
public void reset() throws IOException {
if (closed) {
throw new IOException(sm.getString("inputBuffer.streamClosed"));
}
if (state == CHAR_STATE) {
if (markPos < 0) {
clear(cb);
markPos = -1;
throw new IOException();
} else {
cb.position(markPos);
}
} else {
clear(bb);
}
}
public void checkConverter() throws IOException {
if (conv != null) {
return;
}
Charset charset = null;
if (coyoteRequest != null) {
charset = coyoteRequest.getCharset();
}
if (charset == null) {
charset = org.apache.coyote.Constants.DEFAULT_BODY_CHARSET;
}
SynchronizedStack<B2CConverter> stack = encoders.get(charset);
if (stack == null) {
stack = new SynchronizedStack<>();
encoders.putIfAbsent(charset, stack);
stack = encoders.get(charset);
}
conv = stack.pop();
if (conv == null) {
conv = createConverter(charset);
}
}
private static B2CConverter createConverter(Charset charset) throws IOException {
if (SecurityUtil.isPackageProtectionEnabled()) {
try {
return AccessController.doPrivileged(new PrivilegedCreateConverter(charset));
} catch (PrivilegedActionException ex) {
Exception e = ex.getException();
if (e instanceof IOException) {
throw (IOException) e;
} else {
throw new IOException(e);
}
}
} else {
return new B2CConverter(charset);
}
}
@Override
public void setByteBuffer(ByteBuffer buffer) {
bb = buffer;
}
@Override
public ByteBuffer getByteBuffer() {
return bb;
}
@Override
public void expand(int size) {
// no-op
}
private boolean checkByteBufferEof() throws IOException {
if (bb.remaining() == 0) {
int n = realReadBytes();
if (n < 0) {
return true;
}
}
return false;
}
private boolean checkCharBufferEof() throws IOException {
if (cb.remaining() == 0) {
int n = realReadChars();
if (n < 0) {
return true;
}
}
return false;
}
private void clear(Buffer buffer) {
buffer.rewind().limit(0);
}
private void makeSpace(int count) {
int desiredSize = cb.limit() + count;
if(desiredSize > readLimit) {
desiredSize = readLimit;
}
if(desiredSize <= cb.capacity()) {
return;
}
int newSize = 2 * cb.capacity();
if(desiredSize >= newSize) {
newSize= 2 * cb.capacity() + count;
}
if (newSize > readLimit) {
newSize = readLimit;
}
CharBuffer tmp = CharBuffer.allocate(newSize);
int oldPosition = cb.position();
cb.position(0);
tmp.put(cb);
tmp.flip();
tmp.position(oldPosition);
cb = tmp;
tmp = null;
}
private static class PrivilegedCreateConverter
implements PrivilegedExceptionAction<B2CConverter> {
private final Charset charset;
public PrivilegedCreateConverter(Charset charset) {
this.charset = charset;
}
@Override
public B2CConverter run() throws IOException {
return new B2CConverter(charset);
}
}
}