FELIX-615 Add remote shell contributed by Dieter Wimberger
git-svn-id: https://svn.apache.org/repos/asf/felix/trunk@687053 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/shell.remote/LICENSE b/shell.remote/LICENSE
new file mode 100644
index 0000000..d645695
--- /dev/null
+++ b/shell.remote/LICENSE
@@ -0,0 +1,202 @@
+
+ Apache License
+ Version 2.0, January 2004
+ http://www.apache.org/licenses/
+
+ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
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+ meet the following conditions:
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+ (c) You must retain, in the Source form of any Derivative Works
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+ reproduction, and distribution of the Work otherwise complies with
+ the conditions stated in this License.
+
+ 5. Submission of Contributions. Unless You explicitly state otherwise,
+ any Contribution intentionally submitted for inclusion in the Work
+ by You to the Licensor shall be under the terms and conditions of
+ this License, without any additional terms or conditions.
+ Notwithstanding the above, nothing herein shall supersede or modify
+ the terms of any separate license agreement you may have executed
+ with Licensor regarding such Contributions.
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+ 6. Trademarks. This License does not grant permission to use the trade
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diff --git a/shell.remote/NOTICE b/shell.remote/NOTICE
new file mode 100644
index 0000000..4774f20
--- /dev/null
+++ b/shell.remote/NOTICE
@@ -0,0 +1,28 @@
+Apache Felix Remote Shell
+Copyright 2006-2008 Dieter Wimberger
+
+
+I. Included Software
+
+Apache Felix Remote Shell has been initially developped by Dieter Wimberger.
+Copyright (c) 2008 Dieter Wimberger
+Licensed under the Apache License 2.0.
+
+This product includes software developed at
+The OSGi Alliance (http://www.osgi.org/).
+Copyright 2006 The OSGi Alliance.
+Licensed under the Apache License 2.0.
+
+
+II. Used Software
+
+This product uses software developed at
+The Apache Software Foundation (http://www.apache.org/).
+
+This product uses software developed at
+The OSGi Alliance (http://www.osgi.org/).
+Copyright 2006 The OSGi Alliance.
+Licensed under the Apache License 2.0.
+
+III. License Summary
+- Apache License 2.0
\ No newline at end of file
diff --git a/shell.remote/pom.xml b/shell.remote/pom.xml
new file mode 100644
index 0000000..85392d4
--- /dev/null
+++ b/shell.remote/pom.xml
@@ -0,0 +1,87 @@
+<!--
+ 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.
+-->
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+ <parent>
+ <groupId>org.apache.felix</groupId>
+ <artifactId>felix</artifactId>
+ <version>1.0.2</version>
+ <relativePath>../pom/pom.xml</relativePath>
+ </parent>
+ <modelVersion>4.0.0</modelVersion>
+ <packaging>bundle</packaging>
+ <name>Apache Felix Remote Shell</name>
+ <description>
+ A simple remote textual user interface for Felix' shell service.
+ </description>
+ <version>0.9.0-SNAPSHOT</version>
+ <artifactId>org.apache.felix.shell.remote</artifactId>
+ <dependencies>
+ <dependency>
+ <groupId>${pom.groupId}</groupId>
+ <artifactId>org.osgi.core</artifactId>
+ <version>1.0.0</version>
+ </dependency>
+ <dependency>
+ <groupId>${pom.groupId}</groupId>
+ <artifactId>org.osgi.compendium</artifactId>
+ <version>1.0.1</version>
+ </dependency>
+ <dependency>
+ <groupId>${pom.groupId}</groupId>
+ <artifactId>org.apache.felix.shell</artifactId>
+ <version>1.0.0</version>
+ </dependency>
+ </dependencies>
+ <build>
+ <plugins>
+ <plugin>
+ <groupId>org.apache.felix</groupId>
+ <artifactId>maven-bundle-plugin</artifactId>
+ <version>1.4.0</version>
+ <extensions>true</extensions>
+ <configuration>
+ <instructions>
+ <Private-Package>
+ org.apache.felix.shell.remote.*
+ </Private-Package>
+ <Bundle-Category>console</Bundle-Category>
+ <Bundle-Activator>
+ org.apache.felix.shell.remote.Activator
+ </Bundle-Activator>
+ <Bundle-SymbolicName>
+ ${pom.artifactId}
+ </Bundle-SymbolicName>
+ <Bundle-Vendor>
+ The Apache Software Foundation
+ </Bundle-Vendor>
+ <Bundle-Copyright>
+ Dieter Wimberger
+ </Bundle-Copyright>
+ <Import-Service>
+ org.apache.felix.shell.ShellService
+ </Import-Service>
+ <Import-Service>
+ org.osgi.service.log.LogService
+ </Import-Service>
+ </instructions>
+ </configuration>
+ </plugin>
+ </plugins>
+ </build>
+</project>
diff --git a/shell.remote/src/main/java/org/apache/felix/shell/remote/Activator.java b/shell.remote/src/main/java/org/apache/felix/shell/remote/Activator.java
new file mode 100644
index 0000000..d418b82
--- /dev/null
+++ b/shell.remote/src/main/java/org/apache/felix/shell/remote/Activator.java
@@ -0,0 +1,73 @@
+/*
+* 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.felix.shell.remote;
+
+
+import org.osgi.framework.BundleActivator;
+import org.osgi.framework.BundleContext;
+
+
+/**
+ * Activator for the telnet console.
+ *
+ * @author Dieter Wimberger (wimpi)
+ */
+public class Activator implements BundleActivator
+{
+
+ private static ServiceMediator c_Services;
+ private Listener m_Listener;
+
+
+ public void start( BundleContext bundleContext ) throws Exception
+ {
+ //1. Prepare mediator
+ c_Services = new ServiceMediator();
+ c_Services.activate( bundleContext );
+
+ //2. Prepare the listener
+ m_Listener = new Listener();
+ m_Listener.activate();
+ }
+
+
+ public void stop( BundleContext bundleContext ) throws Exception
+ {
+ if ( m_Listener != null )
+ {
+ m_Listener.deactivate();
+ m_Listener = null;
+ }
+ if ( c_Services != null )
+ {
+ c_Services.deactivate();
+ c_Services = null;
+ }
+ }
+
+
+ /**
+ * Returns a reference to the {@link ServiceMediator} instance used in this bundle.
+ *
+ * @return a {@link ServiceMediator} instance.
+ */
+ public static ServiceMediator getServices()
+ {
+ return c_Services;
+ }
+
+}
diff --git a/shell.remote/src/main/java/org/apache/felix/shell/remote/AtomicInteger.java b/shell.remote/src/main/java/org/apache/felix/shell/remote/AtomicInteger.java
new file mode 100644
index 0000000..79a79f5
--- /dev/null
+++ b/shell.remote/src/main/java/org/apache/felix/shell/remote/AtomicInteger.java
@@ -0,0 +1,93 @@
+/*
+* 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.felix.shell.remote;
+
+
+/**
+ * Provides an atomic integer.
+ * <p/>
+ *
+ * @author Dieter Wimberger (wimpi)
+ */
+class AtomicInteger
+{
+
+ private int m_Value;
+
+
+ public AtomicInteger()
+ {
+ m_Value = 0;
+ }//constructor
+
+
+ /**
+ * Constructs a new <tt>AtomicInteger</tt>
+ * with a given initial value.
+ *
+ * @param value the initial value.
+ */
+ public AtomicInteger( int value )
+ {
+ m_Value = value;
+ }//constructor
+
+
+ /**
+ * Increments this <tt>AtomicInteger</tt> by one.
+ *
+ * @return the resulting value.
+ */
+ public synchronized int increment()
+ {
+ return ++m_Value;
+ }//increment
+
+
+ /**
+ * Decrements this <tt>AtomicInteger</tt> by one.
+ *
+ * @return the resulting value.
+ */
+ public synchronized int decrement()
+ {
+ return --m_Value;
+ }//decrement
+
+
+ /**
+ * Sets the value of this <tt>AtomicInteger</tt>.
+ *
+ * @param i the new value.
+ */
+ public synchronized void set( int i )
+ {
+ m_Value = i;
+ }//set
+
+
+ /**
+ * Returns the value of this <tt>AtomicInteger</tt>.
+ *
+ * @return the actual value.
+ */
+ public synchronized int get()
+ {
+ return m_Value;
+ }//get
+
+}//class AtomicInteger
diff --git a/shell.remote/src/main/java/org/apache/felix/shell/remote/Latch.java b/shell.remote/src/main/java/org/apache/felix/shell/remote/Latch.java
new file mode 100644
index 0000000..49f7507
--- /dev/null
+++ b/shell.remote/src/main/java/org/apache/felix/shell/remote/Latch.java
@@ -0,0 +1,120 @@
+/*
+* 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.felix.shell.remote;
+
+
+/**
+ * A latch is a boolean condition that is set at most once, ever.
+ * Once a single release is issued, all acquires will pass.
+ * <p/>
+ * <b>Sample usage.</b> Here are a set of classes that use
+ * a latch as a start signal for a group of worker threads that
+ * are created and started beforehand, and then later enabled.
+ * <pre>
+ * class Worker implements Runnable {
+ * private final Latch startSignal;
+ * Worker(Latch l) { startSignal = l; }
+ * public void run() {
+ * startSignal.acquire();
+ * doWork();
+ * }
+ * void doWork() { ... }
+ * }
+ * <p/>
+ * class Driver { // ...
+ * void main() {
+ * Latch go = new Latch();
+ * for (int i = 0; i < N; ++i) // make threads
+ * new Thread(new Worker(go)).start();
+ * doSomethingElse(); // don't let run yet
+ * go.release(); // let all threads proceed
+ * }
+ * }
+ * </pre>
+ *
+ * @author Doug Lea
+ */
+class Latch
+{
+
+ protected boolean latched_ = false;
+
+
+ /*
+ This could use double-check, but doesn't.
+ If the latch is being used as an indicator of
+ the presence or state of an object, the user would
+ not necessarily get the memory barrier that comes with synch
+ that would be needed to correctly use that object. This
+ would lead to errors that users would be very hard to track down. So, to
+ be conservative, we always use synch.
+ */
+
+ public void acquire() throws InterruptedException
+ {
+ if ( Thread.interrupted() )
+ throw new InterruptedException();
+ synchronized ( this )
+ {
+ while ( !latched_ )
+ wait();
+ }
+ }//acquire
+
+
+ public boolean attempt( long msecs ) throws InterruptedException
+ {
+ if ( Thread.interrupted() )
+ throw new InterruptedException();
+ synchronized ( this )
+ {
+ if ( latched_ )
+ return true;
+ else if ( msecs <= 0 )
+ return false;
+ else
+ {
+ long waitTime = msecs;
+ long start = System.currentTimeMillis();
+ for ( ;; )
+ {
+ wait( waitTime );
+ if ( latched_ )
+ return true;
+ else
+ {
+ waitTime = msecs - ( System.currentTimeMillis() - start );
+ if ( waitTime <= 0 )
+ return false;
+ }
+ }
+ }
+ }
+ }//attempt
+
+
+ /**
+ * Enable all current and future acquires to pass *
+ */
+ public synchronized void release()
+ {
+ latched_ = true;
+ notifyAll();
+ }//release
+
+}//class Latch
+
diff --git a/shell.remote/src/main/java/org/apache/felix/shell/remote/Listener.java b/shell.remote/src/main/java/org/apache/felix/shell/remote/Listener.java
new file mode 100644
index 0000000..65db291
--- /dev/null
+++ b/shell.remote/src/main/java/org/apache/felix/shell/remote/Listener.java
@@ -0,0 +1,161 @@
+/*
+* 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.felix.shell.remote;
+
+
+import java.io.IOException;
+import java.io.PrintStream;
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.net.SocketException;
+
+
+/**
+ * Implements a simple listener that will accept a single connection.
+ * <p/>
+ *
+ * @author Dieter Wimberger (wimpi)
+ */
+class Listener
+{
+
+ private int m_Port;
+ private Thread m_ListenerThread;
+ private boolean m_Stop = false;
+ private ServerSocket m_ServerSocket;
+ private AtomicInteger m_UseCounter;
+ private int m_MaxConnections;
+
+
+ /**
+ * Activates this listener on a listener thread (telnetconsole.Listener).
+ */
+ public void activate()
+ {
+ //configure from system property
+ try
+ {
+ m_Port = Integer.parseInt( System.getProperty( "osgi.shell.telnet.port", "6666" ) );
+ }
+ catch ( NumberFormatException ex )
+ {
+ Activator.getServices().error( "Listener::activate()", ex );
+ }
+ try
+ {
+ m_MaxConnections = Integer.parseInt( System.getProperty( "osgi.shell.telnet.maxconn", "2" ) );
+ }
+ catch ( NumberFormatException ex )
+ {
+ Activator.getServices().error( "Listener::activate()", ex );
+ }
+ m_UseCounter = new AtomicInteger( 0 );
+ m_ListenerThread = new Thread( new Acceptor(), "telnetconsole.Listener" );
+ m_ListenerThread.start();
+ }//activate
+
+
+ /**
+ * Deactivates this listener.
+ * <p/>
+ * The listener's socket will be closed, which should cause an interrupt in the
+ * listener thread and allow for it to return. The calling thread joins the listener
+ * thread until it returns (to ensure a clean stop).
+ */
+ public void deactivate()
+ {
+ try
+ {
+ m_Stop = true;
+ //wait for the listener thread
+ m_ServerSocket.close();
+ m_ListenerThread.join();
+ }
+ catch ( Exception ex )
+ {
+ Activator.getServices().error( "Listener::deactivate()", ex );
+ }
+ }//deactivate
+
+ /**
+ * Class that implements the listener's accept logic as a <tt>Runnable</tt>.
+ */
+ private class Acceptor implements Runnable
+ {
+
+ /**
+ * Listens constantly to a server socket and handles incoming connections.
+ * One connection will be accepted and routed into the shell, all others will
+ * be notified and closed.
+ * <p/>
+ * The mechanism that should allow the thread to unblock from the ServerSocket.accept() call
+ * is currently closing the ServerSocket from another thread. When the stop flag is set,
+ * this should cause the thread to return and stop.
+ */
+ public void run()
+ {
+ try
+ {
+ /*
+ A server socket is opened with a connectivity queue of a size specified
+ in int floodProtection. Concurrent login handling under normal circumstances
+ should be handled properly, but denial of service attacks via massive parallel
+ program logins should be prevented with this.
+ */
+ m_ServerSocket = new ServerSocket( m_Port, 1 );
+ do
+ {
+ try
+ {
+ Socket s = m_ServerSocket.accept();
+ if ( m_UseCounter.get() >= m_MaxConnections )
+ {
+ //reject with message
+ PrintStream out = new PrintStream( s.getOutputStream() );
+ out.print( INUSE_MESSAGE );
+ out.flush();
+ //close
+ out.close();
+ s.close();
+ }
+ else
+ {
+ m_UseCounter.increment();
+ //run on the connection thread
+ Thread connectionThread = new Thread( new Shell( s, m_UseCounter ) );
+ connectionThread.start();
+ }
+ }
+ catch ( SocketException ex )
+ {
+ }
+ }
+ while ( !m_Stop );
+
+ }
+ catch ( IOException e )
+ {
+ Activator.getServices().error( "Listener.Acceptor::activate()", e );
+ }
+ }//run
+
+ }//inner class Acceptor
+
+ private static final String INUSE_MESSAGE = "Connection refused.\r\n"
+ + "All possible connections are currently being used.\r\n";
+
+}//class Listener
diff --git a/shell.remote/src/main/java/org/apache/felix/shell/remote/ReentrantLock.java b/shell.remote/src/main/java/org/apache/felix/shell/remote/ReentrantLock.java
new file mode 100644
index 0000000..874b3fc
--- /dev/null
+++ b/shell.remote/src/main/java/org/apache/felix/shell/remote/ReentrantLock.java
@@ -0,0 +1,181 @@
+/*
+* 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.felix.shell.remote;
+
+
+/**
+ * Implements a reentrant lock.
+ * <p/>
+ * Public domain code.
+ *
+ * @author Doug Lea
+ */
+class ReentrantLock
+{
+
+ protected Thread m_Owner = null;
+ protected long m_Holds = 0;
+
+
+ public void acquire() throws InterruptedException
+ {
+ //log.debug("acquire()::" + Thread.currentThread().toString());
+ if ( Thread.interrupted() )
+ throw new InterruptedException();
+ Thread caller = Thread.currentThread();
+ synchronized ( this )
+ {
+ if ( caller == m_Owner )
+ ++m_Holds;
+ else
+ {
+ try
+ {
+ while ( m_Owner != null )
+ wait();
+ m_Owner = caller;
+ m_Holds = 1;
+ }
+ catch ( InterruptedException ex )
+ {
+ notify();
+ throw ex;
+ }
+ }
+ }
+ }//acquire
+
+
+ public boolean attempt( long msecs ) throws InterruptedException
+ {
+ //log.debug("attempt()::" + Thread.currentThread().toString());
+ if ( Thread.interrupted() )
+ throw new InterruptedException();
+ Thread caller = Thread.currentThread();
+ synchronized ( this )
+ {
+ if ( caller == m_Owner )
+ {
+ ++m_Holds;
+ return true;
+ }
+ else if ( m_Owner == null )
+ {
+ m_Owner = caller;
+ m_Holds = 1;
+ return true;
+ }
+ else if ( msecs <= 0 )
+ return false;
+ else
+ {
+ long waitTime = msecs;
+ long start = System.currentTimeMillis();
+ try
+ {
+ for ( ;; )
+ {
+ wait( waitTime );
+ if ( caller == m_Owner )
+ {
+ ++m_Holds;
+ return true;
+ }
+ else if ( m_Owner == null )
+ {
+ m_Owner = caller;
+ m_Holds = 1;
+ return true;
+ }
+ else
+ {
+ waitTime = msecs - ( System.currentTimeMillis() - start );
+ if ( waitTime <= 0 )
+ return false;
+ }
+ }
+ }
+ catch ( InterruptedException ex )
+ {
+ notify();
+ throw ex;
+ }
+ }
+ }
+ }//attempt
+
+
+ /**
+ * Release the lock.
+ *
+ * @throws Error thrown if not current owner of lock
+ */
+ public synchronized void release()
+ {
+ //log.debug("release()::" + Thread.currentThread().toString());
+ if ( Thread.currentThread() != m_Owner )
+ throw new Error( "Illegal Lock usage" );
+
+ if ( --m_Holds == 0 )
+ {
+ m_Owner = null;
+ notify();
+ }
+ }//release
+
+
+ /**
+ * Release the lock N times. <code>release(n)</code> is
+ * equivalent in effect to:
+ * <pre>
+ * for (int i = 0; i < n; ++i) release();
+ * </pre>
+ * <p/>
+ *
+ * @param n times the lock should be released.
+ * @throws Error thrown if not current owner of lock
+ * or has fewer than N holds on the lock
+ */
+ public synchronized void release( long n )
+ {
+ if ( Thread.currentThread() != m_Owner || n > m_Holds )
+ throw new Error( "Illegal Lock usage" );
+
+ m_Holds -= n;
+ if ( m_Holds == 0 )
+ {
+ m_Owner = null;
+ notify();
+ }
+ }//release
+
+
+ /**
+ * Return the number of unreleased acquires performed
+ * by the current thread.
+ * Returns zero if current thread does not hold lock.
+ *
+ * @return the number of unreleased acquires performed by the owner thread.
+ */
+ public synchronized long holds()
+ {
+ if ( Thread.currentThread() != m_Owner )
+ return 0;
+ return m_Holds;
+ }//holds
+
+}//class ReentrantLock
diff --git a/shell.remote/src/main/java/org/apache/felix/shell/remote/ServiceMediator.java b/shell.remote/src/main/java/org/apache/felix/shell/remote/ServiceMediator.java
new file mode 100644
index 0000000..fa0d90a
--- /dev/null
+++ b/shell.remote/src/main/java/org/apache/felix/shell/remote/ServiceMediator.java
@@ -0,0 +1,318 @@
+/*
+* 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.felix.shell.remote;
+
+
+import org.apache.felix.shell.ShellService;
+import org.osgi.framework.*;
+import org.osgi.service.log.LogService;
+
+
+/**
+ * Implements a mediator pattern class for services from the OSGi container.
+ * <p/>
+ *
+ * @author Dieter Wimberger (wimpi)
+ */
+class ServiceMediator
+{
+
+ private BundleContext m_BundleContext;
+
+ private ShellService m_FelixShellService;
+ private Latch m_FelixShellServiceLatch;
+
+ private LogService m_LogService;
+ private Latch m_LogServiceLatch;
+
+
+ /**
+ * Returns a reference to the <tt>ShellService</tt> (Felix).
+ *
+ * @param wait time in milliseconds to wait for the reference if it isn't available.
+ * @return the reference to the <tt>ShellService</tt> as obtained from the OSGi service layer.
+ */
+ public ShellService getFelixShellService( long wait )
+ {
+ try
+ {
+ if ( wait < 0 )
+ {
+ m_FelixShellServiceLatch.acquire();
+ }
+ else if ( wait > 0 )
+ {
+ m_FelixShellServiceLatch.attempt( wait );
+ }
+ }
+ catch ( InterruptedException e )
+ {
+ e.printStackTrace( System.err );
+ }
+
+ return m_FelixShellService;
+ }//getFelixShellService
+
+
+ public LogService getLogServiceLatch( long wait )
+ {
+ try
+ {
+ if ( wait < 0 )
+ {
+ m_LogServiceLatch.acquire();
+ }
+ else if ( wait > 0 )
+ {
+ m_LogServiceLatch.attempt( wait );
+ }
+ }
+ catch ( InterruptedException e )
+ {
+ e.printStackTrace( System.err );
+ }
+ return m_LogService;
+ }//getLogService
+
+
+ public void info( String msg )
+ {
+ if ( m_LogService != null )
+ {
+ m_LogService.log( LogService.LOG_INFO, msg );
+ }
+ else
+ {
+ sysout( msg );
+ }
+ }//info
+
+
+ public void error( String msg, Throwable t )
+ {
+ if ( m_LogService != null )
+ {
+ m_LogService.log( LogService.LOG_ERROR, msg, t );
+ }
+ else
+ {
+ syserr( msg, t );
+ }
+ }//error
+
+
+ public void error( String msg )
+ {
+ if ( m_LogService != null )
+ {
+ m_LogService.log( LogService.LOG_ERROR, msg );
+ }
+ else
+ {
+ syserr( msg, null );
+ }
+ }//error
+
+
+ public void debug( String msg )
+ {
+ if ( m_LogService != null )
+ {
+ m_LogService.log( LogService.LOG_DEBUG, msg );
+ }
+ else
+ {
+ sysout( msg );
+ }
+ }//debug
+
+
+ public void warn( String msg )
+ {
+ if ( m_LogService != null )
+ {
+ m_LogService.log( LogService.LOG_WARNING, msg );
+ }
+ else
+ {
+ syserr( msg, null );
+ }
+ }//warn
+
+
+ private void sysout( String msg )
+ {
+ //Assemble String
+ StringBuffer sbuf = new StringBuffer();
+ Bundle b = m_BundleContext.getBundle();
+ sbuf.append( b.getHeaders().get( Constants.BUNDLE_NAME ) );
+ sbuf.append( " [" );
+ sbuf.append( b.getBundleId() );
+ sbuf.append( "] " );
+ sbuf.append( msg );
+ System.out.println( sbuf.toString() );
+ }//sysout
+
+
+ private void syserr( String msg, Throwable t )
+ {
+ //Assemble String
+ StringBuffer sbuf = new StringBuffer();
+ Bundle b = m_BundleContext.getBundle();
+ sbuf.append( b.getHeaders().get( Constants.BUNDLE_NAME ) );
+ sbuf.append( " [" );
+ sbuf.append( b.getBundleId() );
+ sbuf.append( "] " );
+ sbuf.append( msg );
+ System.err.println( sbuf.toString() );
+ if ( t != null )
+ {
+ t.printStackTrace( System.err );
+ }
+ }//logToSystem
+
+
+ /**
+ * Activates this mediator to start tracking the required services using the
+ * OSGi service layer.
+ *
+ * @param bc the bundle's context.
+ * @return true if activated successfully, false otherwise.
+ */
+ public boolean activate( BundleContext bc )
+ {
+ //get the context
+ m_BundleContext = bc;
+
+ m_FelixShellServiceLatch = createWaitLatch();
+ m_LogServiceLatch = createWaitLatch();
+
+ //prepareDefinitions listener
+ ServiceListener serviceListener = new ServiceListenerImpl();
+
+ //prepareDefinitions the filter
+ String filter = "(|(objectclass=" + ShellService.class.getName() + ")" + "(objectclass="
+ + LogService.class.getName() + "))";
+
+ try
+ {
+ //add the listener to the bundle context.
+ bc.addServiceListener( serviceListener, filter );
+
+ //ensure that already registered Service instances are registered with
+ //the manager
+ ServiceReference[] srl = bc.getServiceReferences( null, filter );
+ for ( int i = 0; srl != null && i < srl.length; i++ )
+ {
+ serviceListener.serviceChanged( new ServiceEvent( ServiceEvent.REGISTERED, srl[i] ) );
+ }
+ }
+ catch ( InvalidSyntaxException ex )
+ {
+ ex.printStackTrace( System.err );
+ return false;
+ }
+ return true;
+ }//activate
+
+
+ /**
+ * Deactivates this mediator, nulling out all references.
+ * If called when the bundle is stopped, the framework should actually take
+ * care of unregistering the <tt>ServiceListener</tt>.
+ */
+ public void deactivate()
+ {
+ m_FelixShellService = null;
+ m_FelixShellServiceLatch = null;
+ m_BundleContext = null;
+ }//deactivate
+
+
+ /**
+ * Creates a simple wait latch to be used for the mechanism that allows entities
+ * in the bundles to wait for references.
+ *
+ * @return a new Latch instance.
+ */
+ private Latch createWaitLatch()
+ {
+ return new Latch();
+ }//createWaitLatch
+
+ /**
+ * The <tt>ServiceListener</tt> implementation.
+ */
+ private class ServiceListenerImpl implements ServiceListener
+ {
+
+ public void serviceChanged( ServiceEvent ev )
+ {
+ ServiceReference sr = ev.getServiceReference();
+ Object o = null;
+ switch ( ev.getType() )
+ {
+ case ServiceEvent.REGISTERED:
+ o = m_BundleContext.getService( sr );
+ if ( o == null )
+ {
+ return;
+ }
+ else if ( o instanceof ShellService )
+ {
+ m_FelixShellService = ( ShellService ) o;
+ m_FelixShellServiceLatch.release();
+ }
+ else if ( o instanceof LogService )
+ {
+ m_LogService = ( LogService ) o;
+ m_LogServiceLatch.release();
+ }
+ else
+ {
+ m_BundleContext.ungetService( sr );
+ }
+ break;
+ case ServiceEvent.UNREGISTERING:
+ o = m_BundleContext.getService( sr );
+ if ( o == null )
+ {
+ return;
+ }
+ else if ( o instanceof ShellService )
+ {
+ m_FelixShellService = null;
+ m_FelixShellServiceLatch = createWaitLatch();
+ }
+ else if ( o instanceof LogService )
+ {
+ m_LogService = null;
+ m_LogServiceLatch = createWaitLatch();
+ }
+ else
+ {
+ m_BundleContext.ungetService( sr );
+ }
+ break;
+ }
+ }
+ }//inner class ServiceListenerImpl
+
+ public static long WAIT_UNLIMITED = -1;
+ public static long NO_WAIT = 0;
+
+}//class ServiceMediator
diff --git a/shell.remote/src/main/java/org/apache/felix/shell/remote/Shell.java b/shell.remote/src/main/java/org/apache/felix/shell/remote/Shell.java
new file mode 100644
index 0000000..f7b487e
--- /dev/null
+++ b/shell.remote/src/main/java/org/apache/felix/shell/remote/Shell.java
@@ -0,0 +1,131 @@
+/*
+* 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.felix.shell.remote;
+
+
+import org.apache.felix.shell.ShellService;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.PrintStream;
+import java.net.Socket;
+
+
+/**
+ * Implements the shell.
+ * <p/>
+ *
+ * @author Dieter Wimberger (wimpi)
+ */
+class Shell implements Runnable
+{
+
+ private Socket m_Socket;
+ private AtomicInteger m_UseCounter;
+
+
+ public Shell( Socket s, AtomicInteger counter )
+ {
+ m_Socket = s;
+ m_UseCounter = counter;
+ }//constructor
+
+
+ /**
+ * Runs the shell.
+ */
+ public void run()
+ {
+ try
+ {
+ PrintStream out = new TerminalPrintStream( m_Socket.getOutputStream() );
+ BufferedReader in = new BufferedReader( new TerminalReader( m_Socket.getInputStream(), out ) );
+ ReentrantLock lock = new ReentrantLock();
+
+ // Print welcome banner.
+ out.println();
+ out.println( "Felix Shell Console:" );
+ out.println( "=====================" );
+ out.println( "" );
+
+ do
+ {
+ out.print( "-> " );
+ String line = "";
+ try
+ {
+ line = in.readLine();
+ //make sure to capture end of stream
+ if ( line == null )
+ {
+ exit();
+ return;
+ }
+ }
+ catch ( Exception ex )
+ {
+ exit();
+ return;
+ }
+
+ line = line.trim();
+ if ( line.equalsIgnoreCase( "exit" ) || line.equalsIgnoreCase( "disconnect" ) )
+ {
+ in.close();
+ out.close();
+ exit();
+ return;
+ }
+
+ ShellService shs = Activator.getServices().getFelixShellService( ServiceMediator.NO_WAIT );
+ try
+ {
+ lock.acquire();
+ shs.executeCommand( line, out, out );
+ }
+ catch ( Exception ex )
+ {
+ Activator.getServices().error( "Shell::run()", ex );
+ }
+ finally
+ {
+ lock.release();
+ }
+ }
+ while ( true );
+ }
+ catch ( IOException ex )
+ {
+ Activator.getServices().error( "Shell::run()", ex );
+ }
+ }//run
+
+
+ private void exit()
+ {
+ try
+ {
+ m_Socket.close();
+ }
+ catch ( IOException ex )
+ {
+ Activator.getServices().error( "Shell::exit()", ex );
+ }
+ m_UseCounter.decrement();
+ }//exit
+
+}//class Shell
diff --git a/shell.remote/src/main/java/org/apache/felix/shell/remote/TerminalPrintStream.java b/shell.remote/src/main/java/org/apache/felix/shell/remote/TerminalPrintStream.java
new file mode 100644
index 0000000..30868e1
--- /dev/null
+++ b/shell.remote/src/main/java/org/apache/felix/shell/remote/TerminalPrintStream.java
@@ -0,0 +1,78 @@
+/*
+* 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.felix.shell.remote;
+
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.io.PrintStream;
+
+
+/**
+ * Class implementing a <tt>TerminalPrintStream</tt>.
+ * <p/>
+ *
+ * @author Dieter Wimberger (wimpi)
+ */
+class TerminalPrintStream extends PrintStream
+{
+
+ /**
+ * Constructs a new instance wrapping the given <tt>OutputStream</tt>.
+ *
+ * @param tout the <tt>OutputStream</tt> to be wrapped.
+ */
+ public TerminalPrintStream( OutputStream tout )
+ {
+ super( tout );
+ }//constructor
+
+
+ public void print( String str )
+ {
+ try
+ {
+ byte[] bytes = str.getBytes();
+ out.write( bytes, 0, bytes.length );
+ flush();
+ }
+ catch ( IOException ex )
+ {
+ Activator.getServices().error( "TerminalPrintStream::print()", ex );
+ }
+ }//print
+
+
+ public void println( String str )
+ {
+ print( str + "\r\n" );
+ }//println
+
+
+ public void flush()
+ {
+ try
+ {
+ out.flush();
+ }
+ catch ( IOException ex )
+ {
+ Activator.getServices().error( "TerminalPrintStream::println()", ex );
+ }
+ }//flush
+
+}//class TerminalPrintStream
diff --git a/shell.remote/src/main/java/org/apache/felix/shell/remote/TerminalReader.java b/shell.remote/src/main/java/org/apache/felix/shell/remote/TerminalReader.java
new file mode 100644
index 0000000..afc81ca
--- /dev/null
+++ b/shell.remote/src/main/java/org/apache/felix/shell/remote/TerminalReader.java
@@ -0,0 +1,238 @@
+/*
+* 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.felix.shell.remote;
+
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.PrintStream;
+import java.io.Reader;
+
+
+/**
+ * Class implementing a terminal reader adapter
+ * originally designed for the BeanShell Interpreter.
+ * <p/>
+ * Provides simple line editing (Backspace, Strg-U and a history).
+ *
+ * @author Dieter Wimberger (wimpi)
+ */
+class TerminalReader extends Reader
+{
+
+ protected InputStream m_In;
+ protected PrintStream m_Out;
+ protected boolean m_Echo = false;
+ protected boolean m_EOF = false;
+
+
+ public TerminalReader( InputStream in, PrintStream out )
+ {
+ m_In = in;
+ m_Out = out;
+ }//TerminalReader
+
+
+ /**
+ * Tests if this <tt>TerminalReader</tt> will echo
+ * the character input to the terminal.
+ *
+ * @return true if echo, false otherwise.
+ */
+ public boolean isEcho()
+ {
+ return m_Echo;
+ }//isEcho
+
+
+ /**
+ * Sets if this <tt>TerminalReader</tt> will echo
+ * the character input to the terminal.
+ * <p/>
+ * This only makes sense in character input mode,
+ * in line mode the terminal will handle editing,
+ * and this is recommended for using a more complex shell.
+ * If you implement your own character based editor, you
+ * might as well change this.<br/>
+ * (Default is false).
+ *
+ * @param echo true if echo, false otherwise.
+ */
+ public void setEcho( boolean echo )
+ {
+ m_Echo = echo;
+ }//setEcho
+
+
+ public int read( char[] chars, int off, int len ) throws IOException
+ {
+ if ( m_EOF )
+ {
+ return -1;
+ }
+ for ( int i = off; i < off + len; i++ )
+ {
+ int ch = m_In.read();
+ //shortcut for EOT and simple EOF
+ if ( ch == EOT || ( i == off && ch == -1 ) )
+ {
+ return -1;
+ }
+ chars[i] = ( char ) ch;
+ if ( ch == -1 || ch == 10 || ch == 13 )
+ {
+ m_EOF = ch == -1; //store EOF
+ int read = i - off + 1;
+ if ( m_Echo )
+ {
+ m_Out.write( CRLF );
+ }
+ return read;
+ }
+ //naive backspace handling
+ if ( ch == BS || ch == DEL )
+ {
+ if ( i > off )
+ {
+ i = i - 2;
+ moveLeft( 1 );
+ eraseToEndOfLine();
+ }
+ else
+ {
+ i--;
+ bell();
+ }
+ }
+ else if ( ch == CTRL_U )
+ {
+ moveLeft( i - off );
+ eraseToEndOfLine();
+ i = off - 1;
+ }
+ else
+ {
+ if ( m_Echo )
+ {
+ m_Out.write( chars[i] );
+ }
+ }
+ }
+ return len;
+ }//read
+
+
+ /**
+ * Writes the NVT BEL character to the output.
+ */
+ private void bell()
+ {
+ m_Out.write( BEL );
+ m_Out.flush();
+ }//bell
+
+
+ /**
+ * Writes the standard vt100/ansi cursor moving code to the output.
+ *
+ * @param i the number of times the cursor should be moved left.
+ * @throws IOException if I/O fails.
+ */
+ private void moveLeft( int i ) throws IOException
+ {
+ CURSOR_LEFT[2] = Byte.decode( Integer.toString( i ) ).byteValue();
+ m_Out.write( CURSOR_LEFT );
+ m_Out.flush();
+ }//moveLeft
+
+
+ /**
+ * Writes the standard vt100/ansi sequence for erasing to the end of the current line.
+ *
+ * @throws IOException if I/O fails.
+ */
+ private void eraseToEndOfLine() throws IOException
+ {
+ m_Out.write( ERASE_TEOL );
+ m_Out.flush();
+ }//eraseToEndOfLine
+
+
+ /**
+ * Closes this reader.
+ * Note: will close the input, but not the output.
+ *
+ * @throws IOException
+ */
+ public void close() throws IOException
+ {
+ m_In.close();
+ }//close
+
+ /**
+ * <b>Bell</b><br>
+ * The ANSI defined byte code for the NVT bell.
+ */
+ public static final byte BEL = 7;
+
+ /**
+ * <b>BackSpace</b><br>
+ * The ANSI defined byte code of backspace.
+ */
+ public static final byte BS = 8;
+
+ /**
+ * <b>Delete</b><br>
+ * The ANSI defined byte code of delete.
+ */
+ public static final byte DEL = 127;
+
+ /**
+ * CTRL-u
+ */
+ public static final byte CTRL_U = 21;
+
+ /**
+ * Escape character.
+ */
+ private static byte ESC = 27;
+
+ /**
+ * vt100/ansi standard sequence for moving the cursor left.
+ */
+ private static byte[] CURSOR_LEFT =
+ { ESC, '[', '1', 'D' };
+
+ /**
+ * vt100/ansi standard sequence for erasing everything from the actual cursor to
+ * the end of the current line.
+ */
+ private static byte[] ERASE_TEOL =
+ { ESC, '[', 'K' };
+
+ /**
+ * Standard NVT line break, which HAS TO BE CR and LF.
+ */
+ private static byte[] CRLF =
+ { '\r', '\n' };
+
+ /**
+ * Standard ASCII end of transmission.
+ */
+ private static byte EOT = 4;
+
+}//class TerminalReader