Added support for VCD Database

com.minres.scviewer.database/src/com/minres/scviewer/database/AssociationType.java

@@ -1,3 +1,5 @@
 package com.minres.scviewer.database;
 
-public enum AssociationType {BEGIN, RECORD, END}
+public enum AssociationType {
+	BEGIN, RECORD, END
+}

com.minres.scviewer.database/src/com/minres/scviewer/database/DataType.java

@@ -1,16 +1,18 @@
 package com.minres.scviewer.database;
-  public enum DataType {
-	    BOOLEAN,                       // bool
-	    ENUMERATION,                   // enum
-	    INTEGER,                       // char, short, int, long, long long, sc_int, sc_bigint  
-	    UNSIGNED,                      // unsigned { char, short, int, long, long long }, sc_uint, sc_biguint  
-	    FLOATING_POINT_NUMBER,         // float, double 
-	    BIT_VECTOR,                    // sc_bit, sc_bv
-	    LOGIC_VECTOR,                  // sc_logic, sc_lv
-	    FIXED_POINT_INTEGER,           // sc_fixed
-	    UNSIGNED_FIXED_POINT_INTEGER,  // sc_ufixed
-	    RECORD,                        // struct/class
-	    POINTER,                       // T*
-	    ARRAY,                         // T[N]
-	    STRING                         // string, std::string
-	  };
+
+public enum DataType {
+	BOOLEAN, // bool
+	ENUMERATION, // enum
+	INTEGER, // char, short, int, long, long long, sc_int, sc_bigint
+	UNSIGNED, // unsigned { char, short, int, long, long long }, sc_uint,
+				// sc_biguint
+	FLOATING_POINT_NUMBER, // float, double
+	BIT_VECTOR, // sc_bit, sc_bv
+	LOGIC_VECTOR, // sc_logic, sc_lv
+	FIXED_POINT_INTEGER, // sc_fixed
+	UNSIGNED_FIXED_POINT_INTEGER, // sc_ufixed
+	RECORD, // struct/class
+	POINTER, // T*
+	ARRAY, // T[N]
+	STRING // string, std::string
+};

com.minres.scviewer.database/src/com/minres/scviewer/database/EventTime.java

@@ -16,8 +16,11 @@ public class EventTime implements Comparable<EventTime>{
 	
 	public static final double MS = 1000000000.0;
 
+	public static final EventTime ZERO = new EventTime(0L, "fs");
+	
 	private long value; // unit is femto seconds
 	
+	
 	public EventTime(Long value, String unit){
 		setValue(value, unit);
 	}

com.minres.scviewer.database/src/com/minres/scviewer/database/HierNode.java

@@ -0,0 +1,46 @@
+package com.minres.scviewer.database;
+
+import java.beans.PropertyChangeListener;
+import java.util.ArrayList;
+import java.util.List;
+
+public class HierNode implements IHierNode {
+
+	protected String name;
+	
+	protected ArrayList<IHierNode> childs;
+	
+	public HierNode(String name) {
+		this.name=name;
+		childs = new ArrayList<IHierNode>();
+	}
+
+	@Override
+	public void addPropertyChangeListener(PropertyChangeListener l) {
+	}
+
+	@Override
+	public void removePropertyChangeListener(PropertyChangeListener l) {
+	}
+
+	@Override
+	public String getFullName() {
+		return name;
+	}
+
+	@Override
+	public String getName() {
+		return name;
+	}
+
+	@Override
+	public void setName(String name) {
+		this.name=name;
+	}
+
+	@Override
+	public List<IHierNode> getChildNodes() {
+		return childs;
+	}
+
+}

com.minres.scviewer.database/src/com/minres/scviewer/database/IHierNode.java

@@ -13,7 +13,8 @@ package com.minres.scviewer.database;
 import java.beans.PropertyChangeListener;
 import java.util.List;
 
-public interface ITrHierNode {
+public interface IHierNode {
+	
 	/**
 	 * Attach a non-null PropertyChangeListener to this object.
 	 * 
@@ -23,6 +24,7 @@ public interface ITrHierNode {
 	 *             if the parameter is null
 	 */
 	public void addPropertyChangeListener(PropertyChangeListener l);
+
 	/**
 	 * Remove a PropertyChangeListener from this component.
 	 * 
@@ -37,6 +39,6 @@ public interface ITrHierNode {
 	
 	public void setName(String name);
 	
-	public List<ITrHierNode> getChildNodes();
+	public List<IHierNode> getChildNodes();
 
 }

com.minres.scviewer.database/src/com/minres/scviewer/database/ISignal.java

@@ -0,0 +1,13 @@
+package com.minres.scviewer.database;
+
+import java.util.NavigableSet;
+
+public interface ISignal<T extends ISignalChange> extends IWaveform{
+
+	public NavigableSet<ISignalChange> getSignalChanges();
+
+	public T getSignalChangeByTime(EventTime time);
+
+	public NavigableSet<ISignalChange> getSignalChangesByTimes(EventTime start, EventTime end);
+
+}

com.minres.scviewer.database/src/com/minres/scviewer/database/ISignalChange.java

@@ -0,0 +1,9 @@
+package com.minres.scviewer.database;
+
+public interface ISignalChange extends Comparable<ISignalChange>{
+
+	public EventTime getTime();
+
+	public ISignalChange duplicate() throws CloneNotSupportedException;
+
+}

com.minres.scviewer.database/src/com/minres/scviewer/database/ISignalChangeMulti.java

@@ -0,0 +1,7 @@
+package com.minres.scviewer.database;
+
+public interface ISignalChangeMulti extends ISignalChange {
+	
+	public String getValue();
+
+}

com.minres.scviewer.database/src/com/minres/scviewer/database/ISignalChangeSingle.java

@@ -0,0 +1,7 @@
+package com.minres.scviewer.database;
+
+public interface ISignalChangeSingle extends ISignalChange{
+
+	public char getValue();
+	
+}

com.minres.scviewer.database/src/com/minres/scviewer/database/ITrRelation.java

@@ -1,10 +0,0 @@
-package com.minres.scviewer.database;
-
-public interface ITrRelation {
-
-	RelationType getRelationType();
-	
-	ITransaction getSource();
-	
-	ITransaction getTarget();
-}

com.minres.scviewer.database/src/com/minres/scviewer/database/ITransactionDbFactory.java

@@ -1,9 +0,0 @@
-package com.minres.scviewer.database;
-
-import java.io.File;
-
-public interface ITransactionDbFactory {
-	
-	ITrDb createDatabase(File file);
-
-}

com.minres.scviewer.database/src/com/minres/scviewer/database/ITx.java

@@ -12,23 +12,22 @@ package com.minres.scviewer.database;
 
 import java.util.Collection;
 import java.util.List;
-import java.util.Set;
 
-public interface ITransaction {
+public interface ITx {
 
 	public Long getId();
 	
-	public ITrStream getStream();
+	public ITxStream getStream();
 	
-	public ITrGenerator getGenerator();
+	public ITxGenerator getGenerator();
 	
 	public EventTime getBeginTime();
 	
 	public EventTime getEndTime();
 	
-	public List<ITrAttribute> getAttributes();
+	public List<ITxAttribute> getAttributes();
 	
-	public Collection<ITrRelation> getIncomingRelations();
+	public Collection<ITxRelation> getIncomingRelations();
 
-	public Collection<ITrRelation> getOutgoingRelations();
+	public Collection<ITxRelation> getOutgoingRelations();
 }

com.minres.scviewer.database/src/com/minres/scviewer/database/ITxAttribute.java

@@ -10,6 +10,6 @@
  *******************************************************************************/
 package com.minres.scviewer.database;
 
-public interface ITrAttribute extends ITrAttrType {
+public interface ITxAttribute extends ITxAttributeType {
 	public Object getValue();
 }

com.minres.scviewer.database/src/com/minres/scviewer/database/ITxAttributeType.java

@@ -10,7 +10,7 @@
  *******************************************************************************/
 package com.minres.scviewer.database;
 
-public interface ITrAttrType {
+public interface ITxAttributeType {
 	public String getName();
 	public DataType getDataType();
 	public AssociationType getType();

com.minres.scviewer.database/src/com/minres/scviewer/database/ITxGenerator.java

@@ -12,9 +12,9 @@ package com.minres.scviewer.database;
 
 import java.util.List;
 
-public interface ITrGenerator {
+public interface ITxGenerator {
 	public Long getId();
-	public ITrStream getStream();
+	public ITxStream getStream();
 	public String getName();
-	public List<ITransaction> getTransactions();
+	public List<ITx> getTransactions();
 }

com.minres.scviewer.database/src/com/minres/scviewer/database/ITxRelation.java

@@ -0,0 +1,10 @@
+package com.minres.scviewer.database;
+
+public interface ITxRelation {
+
+	RelationType getRelationType();
+	
+	ITx getSource();
+	
+	ITx getTarget();
+}

com.minres.scviewer.database/src/com/minres/scviewer/database/ITxStream.java

@@ -12,18 +12,12 @@ package com.minres.scviewer.database;
 
 import java.util.List;
 
-public interface  ITrStream extends ITrHierNode {
+public interface  ITxStream extends IWaveform {
 
-	public Long getId();
+	public List<ITxGenerator> getGenerators();
 
-	public String getKind();
+	public List<ITx> getTransactions();
 
-	public ITrDb getDb();
-
-	public List<ITrGenerator> getGenerators();
-
-	public List<ITransaction> getTransactions();
-
-	public ITransaction getTransactionById(long id);
+	public ITx getTransactionById(long id);
 
 }

com.minres.scviewer.database/src/com/minres/scviewer/database/IWaveform.java

@@ -0,0 +1,12 @@
+package com.minres.scviewer.database;
+
+public interface IWaveform extends IHierNode {
+
+	public Long getId();
+
+	public String getKind();
+
+	public IWaveformDb getDb();
+
+
+}

com.minres.scviewer.database/src/com/minres/scviewer/database/IWaveformDb.java

@@ -11,19 +11,18 @@
 package com.minres.scviewer.database;
 
 import java.io.File;
-import java.io.InputStream;
 import java.util.List;
 
 
-public interface ITrDb extends ITrHierNode {
+public interface IWaveformDb extends IHierNode {
 
 	public EventTime getMaxTime();
 	
-	public ITrStream getStreamByName(String name);
+	public IWaveform getStreamByName(String name);
 	
-	public List<ITrStream> getAllStreams();
+	public List<IWaveform> getAllWaves();
 	
-	public void load(File inp) throws InputFormatException;
+	public void load(File inp) throws Exception;
 
 	public void clear();
 

com.minres.scviewer.database/src/com/minres/scviewer/database/IWaveformDbFactory.java

@@ -0,0 +1,9 @@
+package com.minres.scviewer.database;
+
+import java.io.File;
+
+public interface IWaveformDbFactory {
+	
+	IWaveformDb createDatabase(File file);
+
+}

com.minres.scviewer.database/src/com/minres/scviewer/database/SignalChange.java

@@ -0,0 +1,36 @@
+package com.minres.scviewer.database;
+
+public class SignalChange implements ISignalChange {
+	
+	EventTime time;
+	
+	
+	public SignalChange() {
+		time=EventTime.ZERO;
+	}
+
+	public SignalChange(EventTime time) {
+		super();
+		this.time = time;
+	}
+
+	@Override
+	public int compareTo(ISignalChange o) {
+		return time.compareTo(o.getTime());
+	}
+
+	@Override
+	public EventTime getTime() {
+		return time;
+	}
+
+	public void setTime(EventTime time) {
+		this.time = time;
+	}
+
+	@Override
+	public ISignalChange duplicate() throws CloneNotSupportedException {
+		return (ISignalChange) this.clone();
+	}
+
+}

com.minres.scviewer.database/src/com/minres/scviewer/database/vcd/BitVector.java

@@ -0,0 +1,39 @@
+package com.minres.scviewer.database.vcd;
+
+public class BitVector {
+
+	public static final char VALUE_X = 'X';
+	public static final char VALUE_Z = 'Z';
+	public static final char VALUE_1 = '1';
+	public static final char VALUE_0 = '0';
+
+	private final int width;
+	
+	private char[] value;
+	
+	public BitVector(int netWidth) {
+		this.width=netWidth;
+		value = new char[netWidth];
+		for(int i=0; i<netWidth; i++) value[i]='0';
+	}
+
+	public void setValue(int i, char value) {
+		this.value[i]=value;
+	}
+
+	public char[] getValue() {
+		return value;
+	}
+
+	public void setValue(char[] value) {
+		this.value = value;
+	}
+
+	public int getWidth() {
+		return width;
+	}
+
+	public String toString(){
+		return new String(value);
+	}
+}

com.minres.scviewer.database/src/com/minres/scviewer/database/vcd/IVCDDatabaseBuilder.java

@@ -0,0 +1,48 @@
+package com.minres.scviewer.database.vcd;
+
+// TODO: Auto-generated Javadoc
+/**
+ * The Interface ITraceBuilder.
+ */
+public interface IVCDDatabaseBuilder {
+
+	/**
+	 * Enter module.
+	 *
+	 * @param tokenString the token string
+	 */
+	public void enterModule(String tokenString);
+
+	/**
+	 * Exit module.
+	 */
+	public void exitModule();
+
+	/**
+	 * New net.
+	 *
+	 * @param netName the net name
+	 * @param i the index of the net, -1 if a new one, otherwise the id if the referenced
+	 * @param width the width
+	 * @return the integer
+	 */
+	public Integer newNet(String netName, int i, int width) ;
+
+	/**
+	 * Gets the net width.
+	 *
+	 * @param intValue the int value
+	 * @return the net width
+	 */
+	public int getNetWidth(int intValue);
+
+	/**
+	 * Append transition.
+	 *
+	 * @param intValue the int value
+	 * @param fCurrentTime the f current time
+	 * @param decodedValues the decoded values
+	 */
+	public void appendTransition(int intValue, long fCurrentTime, BitVector decodedValues);
+
+}

com.minres.scviewer.database/src/com/minres/scviewer/database/vcd/VCDDb.java

@@ -0,0 +1,211 @@
+package com.minres.scviewer.database.vcd;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Stack;
+import java.util.Vector;
+
+import com.minres.scviewer.database.EventTime;
+import com.minres.scviewer.database.HierNode;
+import com.minres.scviewer.database.ISignal;
+import com.minres.scviewer.database.ISignalChange;
+import com.minres.scviewer.database.ISignalChangeMulti;
+import com.minres.scviewer.database.ISignalChangeSingle;
+import com.minres.scviewer.database.IWaveformDb;
+import com.minres.scviewer.database.IHierNode;
+import com.minres.scviewer.database.ITxStream;
+import com.minres.scviewer.database.IWaveform;
+import com.minres.scviewer.database.InputFormatException;
+import com.minres.scviewer.database.SignalChange;
+
+// TODO: Auto-generated Javadoc
+/**
+ * The Class VCDDb.
+ */
+public class VCDDb extends HierNode implements IWaveformDb, IVCDDatabaseBuilder {
+
+	
+	private static final String TIME_RES = "ps";
+
+	/** The module stack. */
+	private Stack<String> moduleStack;
+	
+	/** The signals. */
+	private List<IWaveform> signals;
+	
+	private HashMap<String, IWaveform> waveformLookup;
+	
+	private long maxTime;
+	
+	/**
+	 * Instantiates a new VCD db.
+	 *
+	 * @param netName the net name
+	 */
+	public VCDDb() {
+		super("VCDDb");
+		signals = new Vector<IWaveform>();
+		waveformLookup = new HashMap<String, IWaveform>();
+	}
+
+	/* (non-Javadoc)
+	 * @see com.minres.scviewer.database.ITrDb#getStreamByName(java.lang.String)
+	 */
+	@Override
+	public ITxStream getStreamByName(String name) {
+		return null;
+	}
+
+	/* (non-Javadoc)
+	 * @see com.minres.scviewer.database.ITrDb#load(java.io.File)
+	 */
+	@SuppressWarnings("unchecked")
+	@Override
+	public void load(File inp) throws Exception {
+		moduleStack= new Stack<String>(); 
+		boolean res = new VCDFileParser(false).load(new FileInputStream(inp), this);
+		moduleStack=null;
+		if(!res) throw new InputFormatException();
+		EventTime lastTime=new EventTime(maxTime, TIME_RES);
+		for(IWaveform signal:signals){
+			ISignalChange change = ((ISignal<ISignalChange>)signal).getSignalChanges().last();
+			if(lastTime.compareTo(change.getTime())>0){
+				ISignalChange lastChange = change.duplicate();
+				((SignalChange)lastChange).setTime(lastTime);
+				((ISignal<ISignalChange>)signal).getSignalChanges().add(lastChange);
+			}
+		}
+		buildHierarchyNodes();
+	}
+
+	/* (non-Javadoc)
+	 * @see com.minres.scviewer.database.ITrDb#clear()
+	 */
+	@Override
+	public void clear() {
+		signals.clear();
+	}
+
+	/* (non-Javadoc)
+	 * @see com.minres.scviewer.database.ITrDb#getMaxTime()
+	 */
+	@Override
+	public EventTime getMaxTime() {
+		return new EventTime(maxTime, TIME_RES);
+	}
+
+	/* (non-Javadoc)
+	 * @see com.minres.scviewer.database.ITrDb#getAllWaves()
+	 */
+	@Override
+	public List<IWaveform> getAllWaves() {
+		return signals;
+	}
+
+	/* (non-Javadoc)
+	 * @see com.minres.scviewer.database.vcd.ITraceBuilder#enterModule(java.lang.String)
+	 */
+	@Override
+	public void enterModule(String tokenString) {
+		if(moduleStack.isEmpty())
+			moduleStack.push(tokenString);
+		else
+			moduleStack.push(moduleStack.peek()+"."+tokenString);
+
+	}
+
+	/* (non-Javadoc)
+	 * @see com.minres.scviewer.database.vcd.ITraceBuilder#exitModule()
+	 */
+	@Override
+	public void exitModule() {
+		if(!moduleStack.isEmpty()) moduleStack.pop();
+	}
+
+	/* (non-Javadoc)
+	 * @see com.minres.scviewer.database.vcd.ITraceBuilder#newNet(java.lang.String, int, int)
+	 */
+	@Override
+	public Integer newNet(String netName, int i, int width) {
+		int id = signals.size();
+		VCDSignal<? extends ISignalChange> signal;
+		if(width==1){
+			signal = i<0 ? new VCDSignal<ISignalChangeSingle>(id, netName) :
+				new VCDSignal<ISignalChangeSingle>(signals.get(i), id, netName);
+		} else {
+			signal = i<0 ? new VCDSignal<ISignalChangeMulti>(id, netName, width) :
+				new VCDSignal<ISignalChangeMulti>(signals.get(i), id, netName);
+		};
+		signals.add(signal);
+		return id;
+	}
+
+	/* (non-Javadoc)
+	 * @see com.minres.scviewer.database.vcd.ITraceBuilder#getNetWidth(int)
+	 */
+	@Override
+	public int getNetWidth(int intValue) {
+		VCDSignal<? extends ISignalChange> signal = (VCDSignal<? extends ISignalChange>) signals.get(intValue);
+		return signal.getWidth();
+	}
+
+	/* (non-Javadoc)
+	 * @see com.minres.scviewer.database.vcd.ITraceBuilder#appendTransition(int, long, com.minres.scviewer.database.vcd.BitVector)
+	 */
+	@SuppressWarnings("unchecked")
+	@Override
+	public void appendTransition(int intValue, long fCurrentTime, BitVector decodedValues) {
+		VCDSignal<? extends ISignalChange> signal = (VCDSignal<? extends ISignalChange>) signals.get(intValue);
+		EventTime time = new EventTime(fCurrentTime, TIME_RES);
+		if(signal.getWidth()==1){
+			VCDSignalChangeSingle change = new VCDSignalChangeSingle(time, decodedValues.getValue()[0]);
+			((VCDSignal<ISignalChangeSingle>)signal).addSignalChange(change);
+		} else {
+			VCDSignalChangeMulti change = new VCDSignalChangeMulti(time, new String(decodedValues.getValue()));
+			((VCDSignal<VCDSignalChangeMulti>)signal).addSignalChange(change);			
+		}
+		maxTime= Math.max(maxTime, fCurrentTime);
+	}
+
+	private void buildHierarchyNodes() throws InputFormatException{
+		for(IWaveform stream:getAllWaves()){
+			waveformLookup.put(stream.getFullName(), stream);
+			String[] hier = stream.getFullName().split("\\.");
+			IHierNode node = this;
+			for(String name:hier){
+				IHierNode n1 = null;
+				 for (IHierNode n : node.getChildNodes()) {
+				        if (n.getName().equals(name)) {
+				            n1=n;
+				            break;
+				        }
+				    }
+				if(name == hier[hier.length-1]){ //leaf
+					if(n1!=null) {
+						if(n1 instanceof HierNode){
+							node.getChildNodes().remove(n1);
+							stream.getChildNodes().addAll(n1.getChildNodes());
+						} else {
+							throw new InputFormatException();
+						}
+					}
+					stream.setName(name);
+					node.getChildNodes().add(stream);
+					node=stream;
+				} else { // intermediate
+					if(n1 != null) {
+						node=n1;
+					} else {
+						HierNode newNode = new HierNode(name);
+						node.getChildNodes().add(newNode);
+						node=newNode;
+					}
+				}
+			}
+		}
+	}
+
+
+}

com.minres.scviewer.database/src/com/minres/scviewer/database/vcd/VCDDbFactory.java

@@ -0,0 +1,37 @@
+package com.minres.scviewer.database.vcd;
+
+import java.io.File;
+import java.io.FileInputStream;
+
+import com.minres.scviewer.database.IWaveformDb;
+import com.minres.scviewer.database.IWaveformDbFactory;
+
+public class VCDDbFactory implements IWaveformDbFactory {
+
+	private byte[] x = "$date".getBytes();
+
+	public VCDDbFactory(){
+		
+	}
+	
+	@Override
+	public IWaveformDb createDatabase(File file) {
+		try {
+			FileInputStream fis = new FileInputStream(file);
+			byte[] buffer = new byte[x.length];
+			int read = fis.read(buffer, 0, x.length);
+			fis.close();
+			if (read == x.length)
+				for (int i = 0; i < x.length; i++)
+					if (buffer[i] != x[i])
+						return null;
+			VCDDb db = new VCDDb();
+			db.load(file);
+			return db;
+		} catch (Exception e) {
+			e.printStackTrace();
+		}
+		return null;
+	}
+
+}

com.minres.scviewer.database/src/com/minres/scviewer/database/vcd/VCDFileParser.java

@@ -0,0 +1,212 @@
+package com.minres.scviewer.database.vcd;
+
+import java.io.*;
+import java.util.*;
+
+class VCDFileParser {
+	private StreamTokenizer tokenizer;
+	private IVCDDatabaseBuilder traceBuilder;
+	private HashMap<String, Integer> nameToNetMap = new HashMap<String, Integer>();
+	private long picoSecondsPerIncrement;
+	private boolean stripNetWidth;
+	long currentTime;
+
+	public VCDFileParser(boolean stripNetWidth) {
+		this.stripNetWidth=stripNetWidth;
+	}
+
+	public boolean load(InputStream is, IVCDDatabaseBuilder builder) {
+		tokenizer = new StreamTokenizer(new BufferedReader(new InputStreamReader(is)));
+		tokenizer.resetSyntax();
+		tokenizer.wordChars(33, 126);
+		tokenizer.whitespaceChars('\r', '\r');
+		tokenizer.whitespaceChars('\n', '\n');
+		tokenizer.whitespaceChars(' ', ' ');
+		tokenizer.whitespaceChars('\t', '\t');
+		try {
+			traceBuilder = builder;
+			currentTime=0;
+			while (parseDefinition());
+			while (parseTransition());
+			return true;
+		} catch (Exception exc) {
+			exc.printStackTrace();
+			return false;
+		}
+	}
+
+	private void parseScope() throws Exception {
+		nextToken(); // Scope type (ignore)
+		nextToken();
+		traceBuilder.enterModule(tokenizer.sval);
+		match("$end");
+	}
+
+	private void parseUpscope() throws Exception {
+		match("$end");
+		traceBuilder.exitModule();
+	}
+
+	private void parseVar() throws Exception {
+		nextToken(); // type
+		nextToken(); // size
+		int width = Integer.parseInt(tokenizer.sval);
+
+		nextToken();
+		String id = tokenizer.sval;
+		nextToken();
+		String netName = tokenizer.sval;
+		while (nextToken() && !tokenizer.sval.equals("$end")) {
+			netName+=tokenizer.sval;
+		}
+
+		Integer net = nameToNetMap.get(id);
+		if (net == null) {
+			// We've never seen this net before
+			if(stripNetWidth){
+				int openBracket = netName.indexOf('[');
+				if (openBracket != -1) netName = netName.substring(0, openBracket);
+			}
+			nameToNetMap.put(id, traceBuilder.newNet(netName, -1, width));
+		} else {
+			// Shares data with existing net. Add as clone.
+			traceBuilder.newNet(netName, net, width);
+		}
+	}
+
+	private void parseTimescale() throws Exception {
+		nextToken();
+		String s = tokenizer.sval;
+		nextToken();
+		while(!tokenizer.sval.equals("$end")){
+			s+=" "+tokenizer.sval;
+			nextToken();
+		}
+		switch (s.charAt(s.length() - 2)){
+		case 'p': // Nano-seconds
+			picoSecondsPerIncrement = 1;
+			s = s.substring(0, s.length() - 2).trim();
+			break;
+		case 'n': // Nano-seconds
+			picoSecondsPerIncrement = 1000;
+			s = s.substring(0, s.length() - 2).trim();
+			break;
+		case 'u': // Microseconds
+			picoSecondsPerIncrement = 1000000;
+			s = s.substring(0, s.length() - 2).trim();
+			break;
+		case 'm': // Microseconds
+			picoSecondsPerIncrement = 1000000000;
+			s = s.substring(0, s.length() - 2).trim();
+			break;
+		default: // Seconds
+			picoSecondsPerIncrement = 1000000000000L;
+			s = s.substring(0, s.length() - 1);
+			break;
+		}
+		picoSecondsPerIncrement *= Long.parseLong(s);
+	}
+
+	private boolean parseDefinition() throws Exception {
+		nextToken();
+		if (tokenizer.sval.equals("$scope"))
+			parseScope();
+		else if (tokenizer.sval.equals("$var"))
+			parseVar();
+		else if (tokenizer.sval.equals("$upscope"))
+			parseUpscope();
+		else if (tokenizer.sval.equals("$timescale"))
+			parseTimescale();
+		else if (tokenizer.sval.equals("$enddefinitions")) {
+			match("$end");
+			return false;
+		} else {
+			// Ignore this defintion
+			do {
+				if (!nextToken()) return false;
+			} while (!tokenizer.sval.equals("$end"));
+		}
+
+		return true;
+	}
+
+	private boolean parseTransition() throws Exception {
+		if (!nextToken()) return false;
+		if (tokenizer.sval.charAt(0) == '#') {	// If the line begins with a #, this is a timestamp.
+			currentTime = Long.parseLong(tokenizer.sval.substring(1)) * picoSecondsPerIncrement;
+		} else {
+			if(tokenizer.sval.equals("$comment")){
+				do {
+					if (!nextToken()) return false;
+				} while (!tokenizer.sval.equals("$end"));
+				return true;
+			}
+			if (tokenizer.sval.equals("$dumpvars") || tokenizer.sval.equals("$end")) return true;
+			String value, id;
+			if (tokenizer.sval.charAt(0) == 'b') {
+				// Multiple value net. Value appears first, followed by space,
+				// then identifier
+				value = tokenizer.sval.substring(1);
+				nextToken();
+				id = tokenizer.sval;
+			} else {
+				// Single value net. identifier first, then value, no space.
+				value = tokenizer.sval.substring(0, 1);
+				id = tokenizer.sval.substring(1);
+			}
+
+			Integer net = nameToNetMap.get(id);
+			if (net == null) {
+				System.out.println("unknown net " + id + " value " + value);
+				return true;
+			}
+
+			int netWidth = traceBuilder.getNetWidth(net);
+			BitVector decodedValues = new BitVector(netWidth);
+			if (value.equals("z") && netWidth > 1) {
+				for (int i = 0; i < netWidth; i++)
+					decodedValues.setValue(i, BitVector.VALUE_Z);
+			} else if (value.equals("x") && netWidth > 1) {
+				for (int i = 0; i < netWidth; i++)
+					decodedValues.setValue(i, BitVector.VALUE_X);
+			} else {
+				int stringIndex = 0;
+				for (int convertedIndex = netWidth - value.length(); convertedIndex < netWidth; convertedIndex++) {
+					switch (value.charAt(stringIndex++)) {
+					case 'z':
+						decodedValues.setValue(convertedIndex, BitVector.VALUE_Z);
+						break;
+
+					case '1':
+						decodedValues.setValue(convertedIndex, BitVector.VALUE_1);
+						break;
+
+					case '0':
+						decodedValues.setValue(convertedIndex, BitVector.VALUE_0);
+						break;
+
+					case 'x':
+						decodedValues.setValue(convertedIndex, BitVector.VALUE_X);
+						break;
+
+					default:
+						decodedValues.setValue(convertedIndex, BitVector.VALUE_X);
+					}
+				}
+			}
+			traceBuilder.appendTransition(net, currentTime, decodedValues);
+		}
+		return true;
+	}
+
+	private void match(String value) throws Exception {
+		nextToken();
+		if (!tokenizer.sval.equals(value)) 
+			throw new Exception("Line "+tokenizer.lineno()+": parse error, expected "+value+" got "+tokenizer.sval);
+	}
+
+	private boolean nextToken() throws IOException {
+		return tokenizer.nextToken() != StreamTokenizer.TT_EOF;
+	}
+
+};

com.minres.scviewer.database/src/com/minres/scviewer/database/vcd/VCDSignal.java

@@ -0,0 +1,108 @@
+package com.minres.scviewer.database.vcd;
+
+import java.util.Collections;
+import java.util.NavigableSet;
+import java.util.TreeSet;
+
+import com.minres.scviewer.database.EventTime;
+import com.minres.scviewer.database.HierNode;
+import com.minres.scviewer.database.ISignal;
+import com.minres.scviewer.database.ISignalChange;
+import com.minres.scviewer.database.IWaveformDb;
+import com.minres.scviewer.database.IWaveform;
+import com.minres.scviewer.database.SignalChange;
+
+public class VCDSignal<T extends ISignalChange> extends HierNode implements ISignal<T> {
+
+	private long id;
+
+	private String fullName;
+
+	private final String kind = "signal";
+	
+	private final int width;
+	
+	private VCDDb db;
+
+	TreeSet<ISignalChange> values;
+	
+	public VCDSignal(String name) {
+		this(0, name, 1);
+	}
+
+	public VCDSignal(int id, String name) {
+		this(id,name,1);
+	}
+
+	public VCDSignal(int id, String name, int width) {
+		super(name);
+		fullName=name;
+		this.id=id;
+		this.width=width;
+		this.values=new TreeSet<ISignalChange>();
+	}
+
+	@SuppressWarnings("unchecked")
+	public VCDSignal(IWaveform other, int id, String name) {
+		super(name);
+		fullName=name;
+		this.id=id;
+		assert(other instanceof VCDSignal<?>);
+		this.width=((VCDSignal<? extends ISignalChange>)other).width;
+		this.values=((VCDSignal<T>)other).values;
+	}
+
+	@Override
+	public String getFullName() {
+		return fullName;
+	}
+
+	public void setId(int id) {
+		this.id=id;
+	}
+
+	@Override
+	public Long getId() {
+		return id;
+	}
+
+	@Override
+	public String getKind() {
+		return kind;
+	}
+
+	public int getWidth() {
+		return width;
+	}
+
+	@Override
+	public IWaveformDb getDb() {
+		return db;
+	}
+
+	public void addSignalChange(T change){
+		values.add(change);
+	}
+	
+	@Override
+	public NavigableSet<ISignalChange> getSignalChanges() {
+		return values;
+	}
+
+	@Override
+	public T getSignalChangeByTime(EventTime time) {
+		return (T) values.floor(new SignalChange(time));
+	}
+
+	@Override
+	public NavigableSet<ISignalChange> getSignalChangesByTimes(EventTime start, EventTime end) {
+		ISignalChange low = values.floor(new SignalChange(start));
+		ISignalChange high = values.ceiling(new SignalChange(end));
+		if(high!=null)
+			return values.subSet(low, true, high, true);
+		else
+			return values.subSet(low, true, values.last(), true);
+	}
+
+
+}

com.minres.scviewer.database/src/com/minres/scviewer/database/vcd/VCDSignalChangeMulti.java

@@ -0,0 +1,28 @@
+package com.minres.scviewer.database.vcd;
+
+import com.minres.scviewer.database.EventTime;
+import com.minres.scviewer.database.ISignalChangeMulti;
+import com.minres.scviewer.database.SignalChange;
+
+public class VCDSignalChangeMulti extends SignalChange implements ISignalChangeMulti, Cloneable  {
+
+	private String value;
+	
+	public VCDSignalChangeMulti(EventTime time) {
+		super(time);
+	}
+
+	public VCDSignalChangeMulti(EventTime time, String value) {
+		super(time);
+		this.value=value;
+	}
+
+	public String getValue() {
+		return value;
+	}
+	
+	public void setValue(String value) {
+		this.value = value;
+	}
+
+}

com.minres.scviewer.database/src/com/minres/scviewer/database/vcd/VCDSignalChangeSingle.java

@@ -0,0 +1,24 @@
+package com.minres.scviewer.database.vcd;
+
+import com.minres.scviewer.database.EventTime;
+import com.minres.scviewer.database.ISignalChangeSingle;
+import com.minres.scviewer.database.SignalChange;
+
+public class VCDSignalChangeSingle extends SignalChange implements ISignalChangeSingle, Cloneable {
+
+	private char value;
+
+	public VCDSignalChangeSingle(EventTime time, char value) {
+		super(time);
+		this.value=value;
+	}
+
+	public char getValue() {
+		return value;
+	}
+
+	public void setValue(char value) {
+		this.value = value;
+	}
+	
+}