ptolemy.domains.ptinyos.kernel

Class PtinyOSDirector

java.lang.Object

ptolemy.kernel.util.NamedObj

ptolemy.kernel.util.Attribute

ptolemy.actor.Director

ptolemy.domains.ptinyos.kernel.PtinyOSDirector

All Implemented Interfaces:

java.lang.Cloneable, Executable, Initializable, Changeable, Debuggable, DebugListener, Derivable, ModelErrorHandler, MoMLExportable, Moveable, Nameable

public class PtinyOSDirector
extends Director

A director for generating, compiling, and simulating nesC code from TinyOS components.

TinyOS is an event-driven operating system designed for sensor network nodes that have very limited resources (e.g., 8K bytes of program memory, 512 bytes of RAM). (More info at http://www.tinyos.net).

nesC is an extension to the C programming language designed to embody the structuring concepts and execution model of TinyOS. (More info at http://nescc.sourceforge.net).

TOSSIM is a C-based simulator for homogeneous TinyOS networks, where all nodes run the same TinyOS program. (More info at http://www.cs.berkeley.edu/~pal/research/tossim.html).

This version of the PtinyOSDirector is for use with TinyOS 1.x only. It is not compatible with TinyOS 2.x.

When embedded in a model containing nesC components (component descriptions converted to MoML from the TinyOS 1.x library using $PTII/ptolemy/domains/ptinyos/util/nc2moml/nc2moml), this director can generate the top-level nesC application file (.nc). This director can also compile the nesC application for use with any TinyOS 1.x-compatible hardware (e.g., mica), or for simulation within Ptolemy II.

When this director is used for code generation only, and not simulation, the user sets the PtinyOSDirector target parameter to a string such as "mica", "mica2", "pc", or another TinyOS 1.x-compatible target. The director will generate a nesC application file (.nc) and a makefile for the application.

When this director is used in simulation mode, the user sets the PtinyOSDirector target parameter to the string "ptII". In addition to the previously mentioned nesC application file (.nc) and a makefile for the application, the director will generate a Java loader file (.java). This loader file implements PtinyOSLoader, which is used as a wrapper for calls to JNI methods in TOSSIM. The director uses the nesC compiler to compile the .nc file into a pre-processed C file. It then uses a C compiler to compile the C file into a shared object (the TOSSIM shared object). The C compiler is usually gcc, though it can use another compiler if $PTCC (defined in $PTII/mk/ptII.mk and used in $TOSROOT/contrib/ptII/ptinyos/tools/make/ptII/ptII.rules) is modified. The director then uses the Java compiler to compile the Java loader file into a .class file. Finally, this director loads the resulting .class using the Java loader, which loads the TOSSIM shared object.

For more information on compilation rules, see: $TOSROOT/contrib/ptII/ptinyos/tools/make/ptII/ptII.rules

TOSSIM contains its own discrete event simulation engine, which consists of a main scheduling loop and a discrete event queue. Events in this queue are ordered by timestamp, which is implemented as a long long (a 64-bit integer on most systems; this is a standard type used in gcc). The timestamp value is a representation of the number of ticks of a 4 MHz clock (the original CPU frequency of the Rene/Mica motes). After initializing its data structures and performing other initialization routines, TOSSIM creates a boot-up event and places the event in its event queue. The version of TOSSIM compiled by this director contains additional calls that are not in the original version of TOSSIM. These calls are JNI calls that cause the TOSSIM scheduler to communicate all events to the PtinyOSDirector, and allow events (and sensor values) generated by Ptolemy II to be passed to the TOSSIM scheduler.

Since TOSSIM operates on a 4MHz clock, users will usually set the timeResolution parameter of this director to the value 0.25E-6, since TOSSIM cannot detect changes in sensor values with time differences less than this time resolution.

When the nesC compiler generates the pre-processed C file for TOSSIM, it automatically generates support for homogeneous networks by instrumenting all component state variables with an array. The array stores the state for each node. Therefore, array index 0 stores the state for node 0, and so on. This director only uses one node per instance of TOSSIM, and hence, only uses array index 0 for all variables. Models containing multiple nodes are created by using a separate PtinyOSDirector (and hence a separate instance of TOSSIM) for each node. In TOSSIM, node 0 is the base station, which is the sink for routing. This director overrides the built-in id number using the nodeID and baseStation parameters, and passes a node ID value to the nesC compiler so that it is hard coded into TOSSIM.

TOSSIM uses TCP/IP sockets attached to network ports for commands and events in order to communicate with external tools, such as TinyViz, a Java-based visualization tool for TOSSIM. We retain these ports for backwards compatibility with TinyViz and other tools. The port numbers are set in commandPort and eventPort. Because of limitations in the implementation of TOSSIM, a separate instance of TinyViz must be attached to each instance of TOSSIM.

Since:

Ptolemy II 5.1

Version:

$Id$

Author:

Elaine Cheong, Yang Zhao, Edward A. Lee

Pt.AcceptedRating:

Yellow (celaine)

Pt.ProposedRating:

Yellow (celaine)

Nested Class Summary

Nested classes/interfaces inherited from class ptolemy.kernel.util.NamedObj

NamedObj.ContainedObjectsIterator

Field Summary

Fields

Modifier and Type	Field and Description
SharedParameter	baseStation Specifies the name of the base station as a string value.
Parameter	bootTimeRange TOSSIM setting for the number of seconds over which nodes may boot.
PtinyOSNodeParameter	commandPort Port number for the TOSSIM command server socket.
Parameter	confirmOverwrite Flag to ask for confirmation before overwriting.
FileParameter	destinationDirectory Output directory for generated code.
Parameter	eventPort Port number for the TOSSIM event server socket.
PtinyOSNodeParameter	nodeID Node ID of this node.
Parameter	numberOfNodes Number of nodes to simulate per instance of TOSSIM.
StringParameter	pflags Additional flags passed to the nesC compiler.
SharedParameter	simulate Flag for choosing whether to simulate the model in ptII.
StringParameter	target Compilation target for the generated nesC code.
FileParameter	tosDir Path to the tos directory of the TinyOS tree.
FileParameter	tosRoot Path to the root of the TinyOS tree.

Fields inherited from class ptolemy.actor.Director

_actorsFinishedExecution, _aspectForActor, _aspectsPresent, _defaultMicrostep, _executionAspects, _finishRequested, _initializables, _nextScheduleTime, _stopRequested, _tokenSentToCommunicationAspect, _zeroTime, localClock, startTime, stopTime

Fields inherited from class ptolemy.kernel.util.NamedObj

_changeListeners, _changeLock, _changeRequests, _debugging, _debugListeners, _deferChangeRequests, _elementName, _isPersistent, _verbose, _workspace, ATTRIBUTES, CLASSNAME, COMPLETE, CONTENTS, DEEP, FULLNAME, LINKS

Fields inherited from interface ptolemy.actor.Executable

COMPLETED, NOT_READY, STOP_ITERATING

Constructor Summary

Constructors

Constructor and Description
PtinyOSDirector() Construct a director in the default workspace with an empty string as its name.
PtinyOSDirector(CompositeEntity container, java.lang.String name) Construct a director with the specified container and name.
PtinyOSDirector(Workspace workspace) Construct a director in the workspace with an empty name.

Method Summary

Modifier and Type	Method and Description
java.nio.channels.SocketChannel	acceptConnection(java.nio.channels.SelectableChannel serverSocketChannel) Accept a connection on a java.nio.channels.ServerSocketChannel.
void	enqueueEvent(java.lang.String newTime) Enqueue the next TOSSIM event into ptII at the specified time by calling fireAt().
void	fire() If the simulate parameter is true, process one event in the TOSSIM event queue and run tasks in task queue.
char	getCharParameterValue(java.lang.String parameter) Get a DoubleToken from the named parameter and convert it to a char.
void	initialize() If the simulate parameter is true, then load the TOSSIM shared library and call TOSSIM main(), by using Java loader calls.
boolean	postfire() Return true if simulation is requested, so that simulated event handling can proceed.
void	preinitialize() Generate nesC code in a .nc file.
void	receivePacket(java.lang.String packet) If the simulate parameter is true, notify the loader that a packet has been received.
void	selectorClose(java.nio.channels.Selector selector) Close the java.nio.channels.Selector.
java.nio.channels.Selector	selectorCreate(java.net.ServerSocket serverSocket, boolean opAccept, boolean opConnect, boolean opRead, boolean opWrite) Create a java.nio.channels.Selector and register the ServerSocketChannel of the ServerSocket with the Selector.
void	selectorRegister(java.nio.channels.Selector selector, java.nio.channels.SelectableChannel socketChannel, boolean opAccept, boolean opConnect, boolean opRead, boolean opWrite) Register the channel with the java.nio.channels.Selector.
java.nio.channels.SelectableChannel	selectSocket(java.nio.channels.Selector selector, boolean[] notNullIfClosing, boolean opAccept, boolean opConnect, boolean opRead, boolean opWrite) Returns a selected channel, or null if none found.
boolean	sendToPort(java.lang.String portName, java.lang.String expression) Send an expression to a ptII port.
void	serverSocketClose(java.net.ServerSocket serverSocket) Close the java.net.ServerSocket.
java.net.ServerSocket	serverSocketCreate(short port) Create a non-blocking server socket and check for connections on the port specified by port.
void	socketChannelClose(java.nio.channels.SelectableChannel socketChannel) Close the java.nio.channels.SocketChannel.
int	socketChannelRead(java.nio.channels.SocketChannel socketChannel, byte[] readBuffer) Read from a java.nio.channels.SocketChannel into readBuffer.
int	socketChannelWrite(java.nio.channels.SocketChannel socketChannel, byte[] writeBuffer) Write the bytes in writeBuffer to a java.nio.channels.SocketChannel.
void	tosDebug(java.lang.String debugMode, java.lang.String message, java.lang.String nodeID) Print a debug message.
void	wrapup() If the simulate parameter is true, call wrapup() in TOSSIM to shut down threads created in initialize().

Methods inherited from class ptolemy.actor.Director

_actorFinished, _consultTimeRegulators, _description, _isEmbedded, _isTopLevel, _schedule, _transferInputs, _transferOutputs, addInitializable, attributeChanged, clone, createSchedule, defaultDependency, delayDependency, elapsedTimeSinceStart, finish, fireAt, fireAt, fireAt, fireAtCurrentTime, fireContainerAt, fireContainerAt, getCausalityInterface, getCurrentTime, getDeadline, getEnvironmentTime, getExecutionAspect, getGlobalTime, getModelNextIterationTime, getModelStartTime, getModelStopTime, getModelTime, getNextIterationTime, getStartTime, getStopTime, getTimeResolution, implementsStrictActorSemantics, initialize, invalidateResolvedTypes, invalidateSchedule, isEmbedded, isFireFunctional, isStopRequested, isStrict, iterate, mutexLockObject, newReceiver, notifyTokenSentToCommunicationAspect, prefire, preinitialize, removeInitializable, requestInitialization, resume, resumeActor, scheduleContainedActors, setContainer, setCurrentTime, setEmbedded, setModelTime, setTimeResolution, stop, stopFire, suggestedModalModelDirectors, supportMultirateFiring, suspend, terminate, transferInputs, transferOutputs, transferOutputs

Methods inherited from class ptolemy.kernel.util.Attribute

_checkContainer, _getContainedObject, _propagateExistence, getContainer, moveDown, moveToFirst, moveToIndex, moveToLast, moveUp, setName, updateContent

Methods inherited from class ptolemy.kernel.util.NamedObj

_addAttribute, _adjustOverride, _attachText, _cloneFixAttributeFields, _containedDecorators, _copyChangeRequestList, _debug, _debug, _debug, _debug, _debug, _executeChangeRequests, _exportMoMLContents, _getIndentPrefix, _isMoMLSuppressed, _markContentsDerived, _notifyHierarchyListenersAfterChange, _notifyHierarchyListenersBeforeChange, _propagateValue, _removeAttribute, _splitName, _stripNumericSuffix, _validateSettables, addChangeListener, addDebugListener, addHierarchyListener, attributeDeleted, attributeList, attributeList, attributeTypeChanged, clone, containedObjectsIterator, decorators, deepContains, depthInHierarchy, description, description, event, executeChangeRequests, exportMoML, exportMoML, exportMoML, exportMoML, exportMoML, exportMoMLPlain, getAttribute, getAttribute, getAttributes, getChangeListeners, getClassName, getDecoratorAttribute, getDecoratorAttributes, getDerivedLevel, getDerivedList, getDisplayName, getElementName, getFullName, getModelErrorHandler, getName, getName, getPrototypeList, getSource, handleModelError, isDeferringChangeRequests, isOverridden, isPersistent, lazyContainedObjectsIterator, message, notifyOfNameChange, propagateExistence, propagateValue, propagateValues, removeAttribute, removeChangeListener, removeDebugListener, removeHierarchyListener, requestChange, setClassName, setDeferringChangeRequests, setDerivedLevel, setDisplayName, setModelErrorHandler, setPersistent, setSource, sortContainedObjects, toplevel, toString, uniqueName, validateSettables, workspace

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

baseStation

public SharedParameter baseStation

Specifies the name of the base station as a string value. The value defaults to the string "\"MicaBoard\"".

bootTimeRange

public Parameter bootTimeRange

TOSSIM setting for the number of seconds over which nodes may boot. The node(s) boots at a random time within this time frame (time starts at 0 seconds). The value defaults to 10 and is of type IntToken.

commandPort

public PtinyOSNodeParameter commandPort

Port number for the TOSSIM command server socket. The value defaults to 10584.

confirmOverwrite

public Parameter confirmOverwrite

Flag to ask for confirmation before overwriting. If false, then overwrite the specified file without asking, if the file exists. If true, then ask for confirmation before overwriting, if the file exists. The value defaults to false, and is of type BooleanToken.

destinationDirectory

public FileParameter destinationDirectory

Output directory for generated code. The value defaults to the current working directory (the ptII expression $CWD).

eventPort

public Parameter eventPort

Port number for the TOSSIM event server socket. This is a public value so that the port number can be set by hand, if necessary. The value defaults to (commandPort + 1).

nodeID

public PtinyOSNodeParameter nodeID

Node ID of this node. This is a substitute for TOS_LOCAL_ADDRESS, which in TOSSIM is normally set to the node array index. However, we assume only one node per TOSSIM. To avoid all nodes being set to the same ID, we use this parameter. In practice, the range is limited by numberOfNodes, and should be such that enough network ports are available for each instance of commandPort and eventPort, though this is not enforced. The value defaults to 1. Normally, the value of this parameter does not need to be changed, since the use of the PtinyOSNodeParameter type for this parameter will cause the value of the node ID to be automatically incremented for each new node in the model. Users should only change this parameter to force a node to have a particular node ID value.

numberOfNodes

public Parameter numberOfNodes

Number of nodes to simulate per instance of TOSSIM. The value defaults to 1, is of type IntToken, and is set to be NOT_EDITABLE.

pflags

public StringParameter pflags

Additional flags passed to the nesC compiler. This can be used, for example, to include additional compilation directories. The value defaults to "-I%T/lib/Counters". "-I" is the normal gcc include directory option. "%T" is a nesC compiler flag that is equivalent to the value of $TOSDIR.

simulate

public SharedParameter simulate

Flag for choosing whether to simulate the model in ptII. The value defaults to true, and is of type BooleanToken. If false, this director only generates files and does not attempt to simulate the model.

target

public StringParameter target

Compilation target for the generated nesC code. Target can be any TinyOS-compatible target, such as mica, mica2, pc, or ptII. The value defaults to "ptII". If target is blank, but simulate is true, then the model will assume that the ptII target has already been compiled and will attempt to simulate.

tosDir

public FileParameter tosDir

Path to the tos directory of the TinyOS tree. TinyOS can be obtained from http://www.tinyos.net. The value defaults to $PTII/vendors/ptinyos/tinyos-1.x/tos

tosRoot

public FileParameter tosRoot

Path to the root of the TinyOS tree. TinyOS can be obtained from http://www.tinyos.net. The value defaults to $PTII/vendors/ptinyos/tinyos-1.x

Constructor Detail

PtinyOSDirector

public PtinyOSDirector()
                throws IllegalActionException,
                       NameDuplicationException

Construct a director in the default workspace with an empty string as its name. The director is added to the list of objects in the workspace. Increment the version number of the workspace.

Throws:

NameDuplicationException - If construction of Time objects fails.

IllegalActionException - If construction of Time objects fails.

PtinyOSDirector

public PtinyOSDirector(Workspace workspace)
                throws IllegalActionException,
                       NameDuplicationException

Construct a director in the workspace with an empty name. The director is added to the list of objects in the workspace. Increment the version number of the workspace.

Parameters:

workspace - The workspace of this object.

Throws:

NameDuplicationException - If construction of Time objects fails.

IllegalActionException - If construction of Time objects fails.

PtinyOSDirector

public PtinyOSDirector(CompositeEntity container,
                       java.lang.String name)
                throws IllegalActionException,
                       NameDuplicationException

Construct a director with the specified container and name.

Parameters:

container - The container.

name - The name of the director.

Throws:

IllegalActionException - If the director is not of an acceptable attribute for the container.

NameDuplicationException - If the name coincides with an attribute already in the container.

Method Detail

enqueueEvent

public void enqueueEvent(java.lang.String newTime)

Enqueue the next TOSSIM event into ptII at the specified time by calling fireAt().

This is a JNI method that gets called by TOSSIM through the Java loader.

Parameters:

newTime - A string representation of the time of the next event. In TOSSIM, unit of time is a tick of a 4MHz clock, and time is stored in a long long in C (a 64-bit integer on most systems).

fire

public void fire()
          throws IllegalActionException

If the simulate parameter is true, process one event in the TOSSIM event queue and run tasks in task queue. This method gets the model time from the director and calls PtinyOSLoader.processEvent(long) with the time as the argument, which invokes TOSSIM.

Specified by:

fire in interface Executable

Overrides:

fire in class Director

Throws:

IllegalActionException - If the fire() method of the super class throws it, or getting a token from the simulateparameter throws it.

getCharParameterValue

public char getCharParameterValue(java.lang.String parameter)

Get a DoubleToken from the named parameter and convert it to a char.

This is a JNI method that gets called by TOSSIM through the Java loader to get a sensor value.

Parameters:

parameter - The parameter.

Returns:

The parameter value, or 0 if the port is not connected or not found or a token cannot be obtained successfully.

initialize

public void initialize()
                throws IllegalActionException

If the simulate parameter is true, then load the TOSSIM shared library and call TOSSIM main(), by using Java loader calls.

The sequence of calls is as follows (assuming simulate is true):

• PtinyOSDirector.initialize()
  • Loads Java PtinyOSLoader class into memory using ClassLoader.loadClass()
  • Creates instance of PtinyOSLoader class (_loader), using Class.newInstance()
  • Calls Java _loader.load()
• Java _loader.load() loads the TOSSIM shared object into memory, using Java System.load()
• PtinyOSDirector.initialize(), continued
  • Calls Java _loader.main()
• Java _loader.main() calls JNI main_unique_name() native method.
• JNI main_unique_name() calls TOSSIM main(), which starts up TOSSIM.

Specified by:

initialize in interface Initializable

Overrides:

initialize in class Director

Throws:

IllegalActionException - If there is a problem initializing the director, such as a problem loading the JNI loader.

postfire

public boolean postfire()
                 throws IllegalActionException

Return true if simulation is requested, so that simulated event handling can proceed.

Specified by:

postfire in interface Executable

Overrides:

postfire in class Director

Returns:

The value of result of the call to postfire() of the super class && the value of the simulate parameter

Throws:

IllegalActionException - If thrown while reading the simulate parameter.

preinitialize

public void preinitialize()
                   throws IllegalActionException

Generate nesC code in a .nc file. If this director is the top most PtinyOSDirector, and the target parameter is non-empty then a .java loader file and a makefile are created. This methods then compiles the .nc and .java files by calling make. The .java file implements the PtinyOSLoader interface.

The sequence of calls is as follows:

• Generates nesC code (.nc), makefile, and Java PtinyOSLoader (.java).
• Runs make, using Runtime.exec()
• Compiles nesC (.nc) code to a TOSSIM shared object (.so or .dll), and the Java PtinyOSLoader (.java) to a Java PtinyOSLoader class (.class).

Specified by:

preinitialize in interface Initializable

Overrides:

preinitialize in class Director

Throws:

IllegalActionException - If the container is not an instance of CompositeActor, the destination directory does not exist and cannot be created, or the nesC file cannot be written.

receivePacket

public void receivePacket(java.lang.String packet)
                   throws IllegalActionException

If the simulate parameter is true, notify the loader that a packet has been received. The PtinyOSCompositeActor.fire() method calls this method with the string value of the input packet.

The sequence of calls is as follows:

• PtinyOSDirector.receivePacket() called (e.g., by the fire() method of the container, which should be a PtinyOSCompositeActor, in response to a packet arriving at the packetIn port).
  • Calls Java _loader.receivePacket() with the packet as a Java String argument.
• _loader.receivePacket() calls JNI receivePacket_unique_name() native method with the packet as a Java String argument.
• JNI receivePacket_unique_name() receives the packet as a JNI jstring argument and converts it into a C const char array. It then calls TOSSIM ptII_receive_packet(), which copies the C const char array into a TOS_Msg data structure. TOSSIM ptII_receive_packet() then calls TOSSIM ptII_insert_packet_event(), which creates a TOSSIM packet event.

This is a wrapper for a native method, where the PtinyOSDirector calls this method (Java) to activate routines in TOSSIM (C).

Parameters:

packet - The string value of the packet to send to TOSSIM.

Throws:

IllegalActionException - If there is a problem reading the simulate parameter.

sendToPort

public boolean sendToPort(java.lang.String portName,
                          java.lang.String expression)

Send an expression to a ptII port. This is used, for example, to send LED or packet data from TOSSIM to the rest of the Ptolemy II model.

This is a JNI method that gets called by TOSSIM through the Java loader to send a value to a ptII port.

The sequence of calls is as follows:

• TOSSIM generates an LED or packet value and calls TOSSIM ptII_updateLeds() or TOSSIM ptII_send_packet(), both of which call JNI _loader.sendToPort() with the port name and value as string arguments.
• _loader.sendToPort() calls Java PtinyOSDirector.sendToPort().
• PtinyOSDirector.sendToPort() performs type conversion from a Java string to the appropriate Token type (depending on the type of the requested port), and sends the token to the requested port using the Java Ptolemy II Port.send() method.

Parameters:

portName - The name of the port.

expression - The expression to send to the ptII port.

Returns:

true if the expression was successfully sent, false if the port is not connected or not found.

tosDebug

public void tosDebug(java.lang.String debugMode,
                     java.lang.String message,
                     java.lang.String nodeID)

Print a debug message.

This is a JNI method that gets called by TOSSIM through the Java loader to print a debug message.

Parameters:

debugMode - A long long in C (currently unused).

message - A char * in C.

nodeID - A short in C.

wrapup

public void wrapup()
            throws IllegalActionException

If the simulate parameter is true, call wrapup() in TOSSIM to shut down threads created in initialize().

The sequence of calls is as follows:

• PtinyOSDirector.wrapup()
  • Calls Java _loader.wrapup()
• _loader.wrapup() calls JNI wrapup_unique_name() native method.
• JNI wrapup_unique_name() calls TOSSIM shutdownSockets(), which:
  • Closes sockets.
  • Joins threads by calling TOSSIM ptII_joinThreads(), which calls JNI _loader.joinThreads().
• _loader.joinThreads() calls Java Thread.join() on all threads created during initialization. Returns Java int value of 0 upon success.
• JNI _loader.joinThreads() returns jint value of 0 upon success, which is converted into a C int and returned by ptII_joinThreads(). If successful, TOSSIM execution stops.

This is a wrapper for a native method, where the PtinyOSDirector calls this method (Java) to activate routines in TOSSIM (C).

Specified by:

wrapup in interface Initializable

Overrides:

wrapup in class Director

Throws:

IllegalActionException - If the wrapup() method of one of the associated actors throws it.

acceptConnection

public java.nio.channels.SocketChannel acceptConnection(java.nio.channels.SelectableChannel serverSocketChannel)

Accept a connection on a java.nio.channels.ServerSocketChannel. If serverSocketChannel is blocking, this method blocks.

This is a JNI method that gets called by TOSSIM through the Java loader.

Parameters:

serverSocketChannel - The ServerSocketChannel on which connections are accepted.

Returns:

The SocketChannel for the connection that was accepted, null if error.

selectorClose

public void selectorClose(java.nio.channels.Selector selector)

Close the java.nio.channels.Selector.

This is a JNI method that gets called by TOSSIM through the Java loader.

Parameters:

selector - The Selector that should be closed.

selectorCreate

public java.nio.channels.Selector selectorCreate(java.net.ServerSocket serverSocket,
                                                 boolean opAccept,
                                                 boolean opConnect,
                                                 boolean opRead,
                                                 boolean opWrite)

Create a java.nio.channels.Selector and register the ServerSocketChannel of the ServerSocket with the Selector.

This is a JNI method that gets called by TOSSIM through the Java loader.

Parameters:

serverSocket - The ServerSocket whose channel should be registered with the Selector created.

opAccept - True if this SelectionKey option should be enabled when registering the ServerSocketChannel to the Selector.

opConnect - True if this SelectionKey option should be enabled when registering the ServerSocketChannel to the Selector.

opRead - True if this SelectionKey option should be enabled when registering the ServerSocketChannel to the Selector.

opWrite - True if this SelectionKey option should be enabled when registering the ServerSocketChannel to the Selector.

Returns:

The Selector created, or null if error.

selectorRegister

public void selectorRegister(java.nio.channels.Selector selector,
                             java.nio.channels.SelectableChannel socketChannel,
                             boolean opAccept,
                             boolean opConnect,
                             boolean opRead,
                             boolean opWrite)

Register the channel with the java.nio.channels.Selector.

This is a JNI method that gets called by TOSSIM through the Java loader.

Parameters:

selector - The selector to which the channel should be registered.

socketChannel - The SocketChannel that should be registered.

opAccept - True if this SelectionKey option should be enabled when registering the SocketChannel to the Selector.

opConnect - True if this SelectionKey option should be enabled when registering the SocketChannel to the Selector.

opRead - True if this SelectionKey option should be enabled when registering the SocketChannel to the Selector.

opWrite - True if this SelectionKey option should be enabled when registering the SocketChannel to the Selector.

selectSocket

public java.nio.channels.SelectableChannel selectSocket(java.nio.channels.Selector selector,
                                                        boolean[] notNullIfClosing,
                                                        boolean opAccept,
                                                        boolean opConnect,
                                                        boolean opRead,
                                                        boolean opWrite)

Returns a selected channel, or null if none found. In selectorClose(Selector), Selector.close() is called, but because of a bug in J2SE described in http://forum.java.sun.com/thread.jspa?threadID=293213&messageID=2671029, the call to Selector.close() in selectorClose(Selector) may never return because a thread is blocked in the call to Selector.select() in this method. So, selectorClose(Selector) also calls Selector.wakeup(), but we have to make sure that this method (and the call to Selector.select()) is not called again, before the Selector is closed, especially since the call to this method will usually be in a loop. We use notNullIfClosing as a flag to indicate that this method should not be called again. We assume that notNullIfClosing is a boolean array of at least size 1. notNullIfClosing[0] is set to true if this method should not be called again, otherwise it is not modified.

This is a JNI method that gets called by TOSSIM through the Java loader.

Parameters:

selector - The channel selector.

notNullIfClosing - notNullIfClosing[0] set to TRUE if returning NULL, otherwise left as is.

opAccept - True if this SelectionKey option should be enabled when returning a non-null SelectableChannel.

opConnect - True if this SelectionKey option should be enabled when returning a non-null SelectableChannel.

opRead - True if this SelectionKey option should be enabled when returning a non-null SelectableChannel.

opWrite - True if this SelectionKey option should be enabled when returning a non-null SelectableChannel.

Returns:

The selected channel, or null if none.

serverSocketClose

public void serverSocketClose(java.net.ServerSocket serverSocket)

Close the java.net.ServerSocket.

This is a JNI method that gets called by TOSSIM through the Java loader.

Parameters:

serverSocket - The ServerSocket to be closed.

serverSocketCreate

public java.net.ServerSocket serverSocketCreate(short port)

Create a non-blocking server socket and check for connections on the port specified by port.

This is a JNI method that gets called by TOSSIM through the Java loader.

Parameters:

port - The port number on which to create a server socket.

Returns:

The ServerSocket created, or null if error.

socketChannelClose

public void socketChannelClose(java.nio.channels.SelectableChannel socketChannel)

Close the java.nio.channels.SocketChannel.

This is a JNI method that gets called by TOSSIM through the Java loader.

Parameters:

socketChannel - The SocketChannel to close.

socketChannelRead

public int socketChannelRead(java.nio.channels.SocketChannel socketChannel,
                             byte[] readBuffer)

Read from a java.nio.channels.SocketChannel into readBuffer.

This is a JNI method that gets called by TOSSIM through the Java loader.

Parameters:

socketChannel - SocketChannel from which to read.

readBuffer - The bytes read.

Returns:

Number of bytes read. Returns 0 if end of stream reached, -1 if error.

socketChannelWrite

public int socketChannelWrite(java.nio.channels.SocketChannel socketChannel,
                              byte[] writeBuffer)

Write the bytes in writeBuffer to a java.nio.channels.SocketChannel.

This is a JNI method that gets called by TOSSIM through the Java loader.

Parameters:

socketChannel - The SocketChannel on which to write.

writeBuffer - The bytes to write.

Returns:

Number of bytes written. -1 if error.