/*
* Copyright 1999,2004 The Apache Software Foundation.
*
* Licensed 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.coyote.tomcat5;
import java.io.IOException;
import java.io.Reader;
import java.security.AccessController;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;
import java.util.HashMap;
import org.apache.coyote.Request;
import org.apache.tomcat.util.buf.B2CConverter;
import org.apache.tomcat.util.buf.ByteChunk;
import org.apache.tomcat.util.buf.CharChunk;
/**
* 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, CharChunk.CharInputChannel,
CharChunk.CharOutputChannel {
// -------------------------------------------------------------- Constants
public static final String DEFAULT_ENCODING =
org.apache.coyote.Constants.DEFAULT_CHARACTER_ENCODING;
public static final int DEFAULT_BUFFER_SIZE = 8*1024;
static final int debug = 0;
// 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;
// ----------------------------------------------------- Instance Variables
/**
* The byte buffer.
*/
private ByteChunk bb;
/**
* The chunk buffer.
*/
private CharChunk cb;
/**
* State of the output buffer.
*/
private int state = 0;
/**
* Number of bytes read.
*/
private int bytesRead = 0;
/**
* Number of chars read.
*/
private int charsRead = 0;
/**
* Flag which indicates if the input buffer is closed.
*/
private boolean closed = false;
/**
* Byte chunk used to input bytes.
*/
private ByteChunk inputChunk = new ByteChunk();
/**
* Encoding to use.
*/
private String enc;
/**
* Encoder is set.
*/
private boolean gotEnc = false;
/**
* List of encoders.
*/
protected HashMap encoders = new HashMap();
/**
* Current byte to char converter.
*/
protected B2CConverter conv;
/**
* Associated Coyote request.
*/
private Request coyoteRequest;
/**
* Buffer position.
*/
private int markPos = -1;
/**
* Buffer size.
*/
private int size = -1;
// ----------------------------------------------------------- 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 = new ByteChunk(size);
bb.setLimit(size);
bb.setByteInputChannel(this);
cb = new CharChunk(size);
cb.setLimit(size);
cb.setOptimizedWrite(false);
cb.setCharInputChannel(this);
cb.setCharOutputChannel(this);
}
// ------------------------------------------------------------- Properties
/**
* Associated Coyote request.
*
* @param coyoteRequest Associated Coyote request
*/
public void setRequest(Request coyoteRequest) {
this.coyoteRequest = coyoteRequest;
}
/**
* Get associated Coyote request.
*
* @return the associated Coyote request
*/
public Request getRequest() {
return this.coyoteRequest;
}
// --------------------------------------------------------- Public Methods
/**
* Recycle the output buffer.
*/
public void recycle() {
if (debug > 0)
log("recycle()");
state = INITIAL_STATE;
bytesRead = 0;
charsRead = 0;
// If usage of mark made the buffer too big, reallocate it
if (cb.getChars().length > size) {
cb = new CharChunk(size);
cb.setLimit(size);
cb.setCharInputChannel(this);
cb.setCharOutputChannel(this);
} else {
cb.recycle();
}
markPos = -1;
bb.recycle();
closed = false;
if (conv != null) {
conv.recycle();
}
gotEnc = false;
enc = null;
}
/**
* Close the input buffer.
*
* @throws IOException An underlying IOException occurred
*/
public void close()
throws IOException {
closed = true;
}
public int available()
throws IOException {
if (state == BYTE_STATE) {
return bb.getLength();
} else if (state == CHAR_STATE) {
return cb.getLength();
} else {
return 0;
}
}
// ------------------------------------------------- Bytes Handling Methods
/**
* Reads new bytes in the byte chunk.
*
* @param buf Byte buffer to be written to the response
* @param off Offset
* @param cnt Length
*
* @throws IOException An underlying IOException occurred
*/
public int realReadBytes(byte cbuf[], int off, int len)
throws IOException {
if (debug > 2)
log("realRead() " + coyoteRequest);
if (closed)
return -1;
if (coyoteRequest == null)
return -1;
state = BYTE_STATE;
int result = coyoteRequest.doRead(bb);
return result;
}
public int readByte()
throws IOException {
return bb.substract();
}
public int read(byte[] b, int off, int len)
throws IOException {
return bb.substract(b, off, len);
}
// ------------------------------------------------- Chars Handling Methods
/**
* Since the converter will use append, it is possible to get chars to
* be removed from the buffer for "writing". Since the chars have already
* been read before, they are ignored. If a mark was set, then the
* mark is lost.
*/
public void realWriteChars(char c[], int off, int len)
throws IOException {
markPos = -1;
}
public void setEncoding(String s) {
enc = s;
}
public int realReadChars(char cbuf[], int off, int len)
throws IOException {
if (debug > 0)
log("realRead() " + cb.getOffset() + " " + len);
if (!gotEnc)
setConverter();
if (debug > 0)
log("encoder: " + conv + " " + gotEnc);
if (bb.getLength() <= 0) {
int nRead = realReadBytes(bb.getBytes(), 0, bb.getBytes().length);
if (nRead < 0) {
return -1;
}
}
if (markPos == -1) {
cb.setOffset(0);
cb.setEnd(0);
}
conv.convert(bb, cb);
bb.setOffset(bb.getEnd());
state = CHAR_STATE;
return cb.getLength();
}
public int read()
throws IOException {
return cb.substract();
}
public int read(char[] cbuf)
throws IOException {
return read(cbuf, 0, cbuf.length);
}
public int read(char[] cbuf, int off, int len)
throws IOException {
return cb.substract(cbuf, off, len);
}
public long skip(long n)
throws IOException {
if (n < 0) {
throw new IllegalArgumentException();
}
long nRead = 0;
while (nRead < n) {
if (cb.getLength() >= n) {
cb.setOffset(cb.getStart() + (int) n);
nRead = n;
} else {
nRead += cb.getLength();
cb.setOffset(cb.getEnd());
int toRead = 0;
if (cb.getChars().length < (n - nRead)) {
toRead = cb.getChars().length;
} else {
toRead = (int) (n - nRead);
}
int nb = realReadChars(cb.getChars(), 0, toRead);
if (nb < 0)
break;
}
}
return nRead;
}
public boolean ready()
throws IOException {
return (cb.getLength() > 0);
}
public boolean markSupported() {
return true;
}
public void mark(int readAheadLimit)
throws IOException {
if (cb.getLength() <= 0) {
cb.setOffset(0);
cb.setEnd(0);
}
cb.setLimit(cb.getStart() + readAheadLimit);
markPos = cb.getStart();
}
public void reset()
throws IOException {
if (state == CHAR_STATE) {
if (markPos < 0) {
cb.recycle();
markPos = -1;
throw new IOException();
} else {
cb.setOffset(markPos);
}
} else {
bb.recycle();
}
}
public void checkConverter()
throws IOException {
if (!gotEnc)
setConverter();
}
protected void setConverter()
throws IOException {
if (coyoteRequest != null)
enc = coyoteRequest.getCharacterEncoding();
if (debug > 0)
log("Got encoding: " + enc);
gotEnc = true;
if (enc == null)
enc = DEFAULT_ENCODING;
conv = (B2CConverter) encoders.get(enc);
if (conv == null) {
if (System.getSecurityManager() != null){
try{
conv = (B2CConverter)AccessController.doPrivileged(
new PrivilegedExceptionAction(){
public Object run() throws IOException{
return new B2CConverter(enc);
}
}
);
}catch(PrivilegedActionException ex){
Exception e = ex.getException();
if (e instanceof IOException)
throw (IOException)e;
if (debug > 0)
log("setConverter: " + ex.getMessage());
}
} else {
conv = new B2CConverter(enc);
}
encoders.put(enc, conv);
}
}
protected void log( String s ) {
System.out.println("InputBuffer: " + s);
}
}