/*
* Portions Copyright 2000-2007 Sun Microsystems, Inc. All Rights
* Reserved. Use is subject to license terms.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
*
* This program 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.
*
* This program 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 at /legal/license.txt).
*
* 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
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
* Clara, CA 95054 or visit www.sun.com if you need additional
* information or have any questions.
*/
/*
*/
package gov.nist.siplite.parser;
import gov.nist.siplite.message.*;
import gov.nist.siplite.header.*;
import gov.nist.core.*;
import java.io.*;
import com.sun.midp.log.Logging;
import com.sun.midp.log.LogChannels;
/**
* This implements a pipelined message parser suitable for use
* with a stream - oriented input such as TCP. The client uses
* this class by instatiating with an input stream from which
* input is read and fed to a message parser.
* It keeps reading from the input stream and process messages in a
* never ending interpreter loop. The message listener interface gets called
* for processing messages or for processing errors. The payload specified
* by the content-length header is read directly from the input stream.
* This can be accessed from the Message using the getContent and
* getContentBytes methods provided by the Message class.
*
* @version JAIN-SIP-1.1
*
* <a href="{@docRoot}/uncopyright.html">This code is in the public domain.</a>
*
* It was noticed that the parser was
* blocking so I threw out some cool pipelining which ran fast but only worked
* when the phase of the full moon matched its mood. Now things are serialized
* and life goes slower but more reliably.
*
* @see SIPMessageListener
*/
public final class PipelinedMsgParser
implements Runnable {
/**
* The message listener that is registered with this parser.
* (The message listener has methods that can process correct
* and erroneous messages.)
*/
protected SIPMessageListener sipMessageListener;
/** Handle to the preprocssor thread. */
private Thread mythread;
/* Current message body contents. */
// private byte[] messageBody;
/* Flag to indicate an error was found. */
// private boolean errorFlag;
/** Raw data input to be processed. */
private InputStream rawInputStream;
/** Default constructor. */
protected PipelinedMsgParser() {
super();
}
/**
* Constructor when we are given a message listener and an input stream
* (could be a TCP connection or a file)
* @param sipMessageListener Message listener which has
* methods that get called
* back from the parser when a parse is complete
* @param in Input stream from which to read the input.
* @param debug Enable/disable tracing or lexical analyser switch.
*/
public PipelinedMsgParser(
SIPMessageListener sipMessageListener,
InputStream in,
boolean debug) {
this();
this.sipMessageListener = sipMessageListener;
rawInputStream = in;
mythread = new Thread(this);
}
/**
* This is the constructor for the pipelined parser.
* @param mhandler a MessageListener implementation that
* provides the message handlers to
* handle correctly and incorrectly parsed messages.
* @param in An input stream to read messages from.
*/
public PipelinedMsgParser
(SIPMessageListener mhandler, InputStream in) {
this(mhandler, in, false);
}
/**
* This is the constructor for the pipelined parser.
* @param in - An input stream to read messages from.
*/
public PipelinedMsgParser(InputStream in) {
this(null, in, false);
}
/**
* Start reading and processing input.
*/
public void processInput() {
mythread.start();
}
/**
* Create a new pipelined parser from an existing one.
* @return A new pipelined parser that reads from the same input
* stream.
*/
protected Object clone() {
PipelinedMsgParser p = new PipelinedMsgParser();
p.rawInputStream = this.rawInputStream;
p.sipMessageListener = this.sipMessageListener;
return p;
}
/**
* Add a class that implements a MessageListener interface whose
* methods get called * on successful parse and error conditons.
* @param mlistener a MessageListener
* implementation that can react to correct and incorrect
* pars.
*/
public void setMessageListener(SIPMessageListener mlistener) {
sipMessageListener = mlistener;
}
/**
* Reads a line of input (I cannot use buffered reader because we
* may need to switch encodings mid-stream!
* @param inputStream source for data to be processed
* @return the line of text retrieved
* @exception IOException if an error occurs reading from input
*/
private String readLine(InputStream inputStream)
throws IOException {
StringBuffer retval = new StringBuffer("");
while (true) {
char ch;
int i = inputStream.read();
if (i == -1) {
throw new IOException("End of stream");
} else {
ch = (char) i;
}
if (ch != '\r') {
retval.append(ch);
}
if (ch == '\n') {
break;
}
}
return retval.toString();
}
/**
* Reads to the next break (CRLFCRLF sequence).
* @param inputStream source for data to be processed
* @return the text up to the break character sequence
* @exception IOException if an error occurs reading from input
*/
private String readToBreak(InputStream inputStream)
throws IOException {
StringBuffer retval = new StringBuffer("");
boolean flag = false;
while (true) {
char ch;
int i = inputStream.read();
if (i == -1)
break;
else
ch = (char) i;
if (ch != '\r')
retval.append(ch);
if (ch == '\n') {
if (flag)
break;
else
flag = true;
}
}
return retval.toString();
}
/**
* This is input reading thread for the pipelined parser.
* You feed it input through the input stream (see the constructor)
* and it calls back an event listener interface for message
* processing or error.
* It cleans up the input - dealing with things like line continuation
*
*/
public void run() {
InputStream inputStream = this.rawInputStream;
// I cannot use buffered reader here because we may need to switch
// encodings to read the message body.
try {
while (true) {
StringBuffer inputBuffer = new StringBuffer();
if (Logging.REPORT_LEVEL <= Logging.INFORMATION) {
Logging.report(Logging.INFORMATION, LogChannels.LC_JSR180,
"Starting parse!");
}
String line1;
String line2 = null;
// ignore blank lines.
while (true) {
line1 = readLine(inputStream);
if (line1.equals("\n")) {
if (Logging.REPORT_LEVEL <= Logging.INFORMATION) {
Logging.report(Logging.INFORMATION,
LogChannels.LC_JSR180,
"Discarding " + line1);
}
continue;
} else {
break;
}
}
if (Logging.REPORT_LEVEL <= Logging.INFORMATION) {
Logging.report(Logging.INFORMATION, LogChannels.LC_JSR180,
"line1 = " + line1);
}
inputBuffer.append(line1);
while (true) {
line2 = readLine(inputStream);
inputBuffer.append(line2);
if (line2.trim().equals("")) break;
}
inputBuffer.append(line2);
StringMsgParser smp =
new StringMsgParser(sipMessageListener);
smp.readBody = false;
Message sipMessage = null;
try {
sipMessage =
smp.parseSIPMessage(inputBuffer.toString());
if (sipMessage == null) continue;
} catch (ParseException ex) {
// Just ignore the parse exception.
continue;
}
if (Logging.REPORT_LEVEL <= Logging.INFORMATION) {
Logging.report(Logging.INFORMATION, LogChannels.LC_JSR180,
"Completed parsing message");
}
ContentLengthHeader cl =
sipMessage.getContentLengthHeader();
int contentLength = 0;
if (cl != null) {
contentLength = cl.getContentLength();
} else {
contentLength = 0;
}
if (contentLength == 0) {
if (Logging.REPORT_LEVEL <= Logging.INFORMATION) {
Logging.report(Logging.INFORMATION,
LogChannels.LC_JSR180,
"content length " + contentLength);
}
sipMessage.removeContent();
} else { // deal with the message body.
contentLength = cl.getContentLength();
if (Logging.REPORT_LEVEL <= Logging.INFORMATION) {
Logging.report(Logging.INFORMATION,
LogChannels.LC_JSR180,
"content length " + contentLength);
}
byte[] message_body = new byte[contentLength];
int nread = 0;
while (nread < contentLength) {
int readlength =
inputStream.read
(message_body, nread,
contentLength -
nread);
if (readlength > 0) {
nread += readlength;
if (Logging.REPORT_LEVEL <=
Logging.INFORMATION) {
Logging.report(Logging.INFORMATION,
LogChannels.LC_JSR180,
"read " + nread);
}
} else {
break;
}
}
sipMessage.setMessageContent(message_body);
}
if (sipMessageListener != null) {
sipMessageListener.processMessage(sipMessage);
}
}
} catch (IOException ex) {
if (sipMessageListener != null) {
sipMessageListener.handleIOException();
}
} finally {
}
}
}
|
