/**
* .
* Copyright © 1999 Erich P G.
*
*/
package creator.compiler;
import java.util.Vector;
import java.util.Stack;
import com.sun.xml.tree.XmlDocument;
import com.sun.xml.tree.XmlDocumentBuilder;
import com.sun.xml.tree.ElementNode;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import org.w3c.dom.Node;
import org.w3c.dom.CharacterData;
import autohit.Sim;
import autohit.vm.*;
/**
* This is the a Sim compiler. It will compile xml documents that conform
* to the "%AUTOHIT_ROOT%/lib/sim.dtd" dtd into a Sim object.
*
* WARNING!!! For the compiler to work, the FIRST element of the java
* CLASSPATH must be the root for the autohit installation. The compiler
* needs to find the "sim.dtd" file in the "%AUTOHIT_ROOT%/lib" directory.
*
* The private methos translate Token() matches the textual tokens, as defined in the
* dtd to numerics that are used by the rest of the compiler. Any new tokens
* need to be added to that method.
*
* I can think of several more elegant approaches to making this compiler, but until the
* XML parsers settle a bit, I'm not going to bother...
*
* IMPORTANT NOTE!!!! The XML parser WITH DTD ensure instructions are
* coded in the proper order. ALL of the code below assumes this!!!
* If instructions come out of order or in disallowed places
* (like a seek outside of a get), I GUARANTEE you'll get a runaway
* compiler...,
*
* We will look for imbedded variables only in certain locations.
*
* @see autohit.Sim
*
* @author Erich P. Gatejen
* @version 1.0
* Version History
* EPG - Initial - 14Jan99
* EPG - Dumb-bug fix - 8Mar99
*
*/
public class SimCompiler extends XmlCompiler {
// --- FINAL FIELDS ------------------------------------------------------
private final static String dtdName = "sim.dtd";
private final static int tokNULL = 0;
private final static int tokNAME = 1;
private final static int tokNOTE = 2;
private final static int tokVERSION = 3;
private final static int tokSET = 4;
private final static int tokFOR = 5;
private final static int tokWHILE = 6;
private final static int tokIF = 7;
private final static int tokWAIT = 8;
private final static int tokGET = 9;
private final static int tokHEADER = 10;
private final static int tokNV = 11;
private final static int tokBLOCK = 12;
private final static int tokADD = 13;
private final static int tokVERIFY = 14;
private final static int tokSEEK = 15;
private final static int tokEXEC = 16;
// --- FIELDS ------------------------------------------------------------
/**
* The work-in-progress Sim object.
*/
protected Sim workingSim;
// --- PUBLIC METHODS ----------------------------------------------------
/**
* Constructor. This is the only and default constructor.
*
* @throws Exception any exception invalidates the compiler.
*/
public SimCompiler() throws Exception {
super(dtdName);
}
/**
* Compile the xml tree into a Sim object. This method implements
* the abstract method in XmlCompiler. It will be automatically
* called after the source document is parsed into an xml tree.
*
* @param xd A parsed XML document.
* @return a reference to the target object.
*
* @see autohit.Sim
* @see creator.compiler.SimCompiler
*/
public Object build(XmlDocument xd) {
// Any exception or verification check aborts the compile
try {
// Ok, build our working Sim object
workingSim = new Sim();
workingSim.init();
// Get the root element and normalize
ElementNode root = (ElementNode) xd.getDocumentElement();
root.normalize();
// Peal out the and sub-trees
NodeList rootChildren = root.getChildNodes();
ElementNode itemTree = (ElementNode) rootChildren.item(0);
ElementNode codeTree = (ElementNode) rootChildren.item(1);
// Deal with the tree
for (int idx = 0; idx < itemTree.getLength(); idx++) {
processItem((ElementNode)itemTree.item(idx));
}
// Deal with the tree
// Basicall, I'm gonna go wtih recursion. I don't think it should
// get very deep.
try {
processCode(codeTree);
// Put a NOP on the end of the executable
workingSim.exec.add(new VMINop());
workingSim.exec.trimToSize();
} catch (Exception e) {
// an otherwise uncaught exception. A runaway compiler...
err.error("Runaway compilation errors. Stopping compile...");
return null;
}
} catch (Exception e) {
err.error("Compiler internal error. Stopping compile...");
return null; // leave the objectCode as null;
}
return workingSim;
}
// == ===============================================================================
// == = PRIVATE METHODS =
// == ===============================================================================
/**
* Processes info section tags.
*/
private void processItem(ElementNode en) {
switch( translateToken(en.getNodeName()) ) {
case tokNAME:
// Pull the child text element and place it the Sim.name;
String nameText = getText(en.getFirstChild());
if (nameText == null) {
err.error("Empty tag.");
} else {
workingSim.name = nameText;
}
break;
// For now, we are ignoring UIDs
case tokNOTE:
// Notes will append. Pull the child text element and paste it to the
// Sim.note.
String noteText = getText(en.getFirstChild());
if (noteText == null) {
err.error("Empty tag.");
} else {
workingSim.note = new String(workingSim.note + noteText);
}
break;
case tokVERSION:
// For now, ignore VERSION
break;
case tokNULL:
default:
err.error("Software Detected Fault: creator.compiler.SimCompiler.processItem(). The textual token [" + en.getNodeName() + "] should have NOT reached this code. Check the XML DTD associated with the SimCompiler.");
}
}
/**
* Every raw element will enter here. Bascially, it dispatches it to it's specific
* handler. It will do so for every child in the passed node.
*/
private void processCode(ElementNode en) throws Exception {
ElementNode child;
//DEBUG
//System.out.println("ENTER --- " + en.getNodeName());
for (int idx = 0; idx < en.getLength(); idx++) {
child = (ElementNode)en.item(idx);
//DEBUG
//System.out.println(" --- CHILD " + child.getNodeName());
switch( translateToken(child.getNodeName()) ) {
case tokSET:
handleSet(child);
break;
case tokWAIT:
handleWait(child);
break;
case tokGET:
handleGet(child);
break;
case tokHEADER:
handleHeader(child);
break;
case tokNV:
handleNV(child);
break;
case tokFOR:
handleFor(child);
break;
case tokWHILE:
handleWhile(child);
break;
case tokIF:
handleIf(child);
break;
case tokBLOCK:
handleBlock(child);
break;
case tokADD:
handleAdd(child);
break;
case tokVERIFY:
handleVerify(child);
break;
case tokSEEK:
handleSeek(child);
break;
case tokEXEC:
handleExec(child);
break;
case tokNULL:
default:
err.error("Software Detected Fault: creator.compiler.SimCompiler.processItem(). The textual token [" + en.getNodeName() + "] should have NOT reached this code. Check the XML DTD associated with the SimCompiler.");
throw (new Exception("Software Detected Fault in creator.compiler.SimCompiler.processItem()."));
} // end switch
} // end for
//DEBUG
//System.out.println("EXIT --- " + en.getNodeName());
}
// == ===============================================================================
// == = TOKEN HANDLERS =
// == ===============================================================================
/**
* Emit a set instruction. Simple enough.
*/
private void handleSet(ElementNode en) {
String name = en.getAttribute("name");
String value = en.getAttribute("value");
if (!isValid(name)) {
errBadAttribute(en.toString(), "name", "set");
} else if (!isValid(value)) {
errBadAttribute(en.toString(), "value", "set");
} else {
VMISet emitable = new VMISet();
emitable.name = name;
emitable.value = value;
emitable.orIV(seekIV(name)||seekIV(value));
workingSim.exec.add(emitable);
}
}
/**
* Emit an add instruction.
*/
private void handleAdd(ElementNode en) {
String name = en.getAttribute("name");
String value = en.getAttribute("value");
if (!isValid(name)) {
errBadAttribute(en.toString(), "name", "add");
} else if (!isValid(value)) {
errBadAttribute(en.toString(), "value", "add");
} else {
VMIAdd emitable = new VMIAdd();
emitable.name = name;
emitable.value = value;
emitable.orIV(seekIV(name)||seekIV(value));
workingSim.exec.add(emitable);
}
}
/**
* Emit a wait instruction. Simple enough.
*/
private void handleWait(ElementNode en) {
String time = en.getAttribute("time");
if (isValid(time)) {
VMIWait emitable = new VMIWait();
emitable.time = time;
emitable.orIV(seekIV(time));
workingSim.exec.add(emitable);
} else {
errBadAttribute(en.toString(), "time", "wait");
}
}
/**
* Emit a get instruction.
*/
private void handleGet(ElementNode en) {
String qs = en.getAttribute("qs");
if (isValid(qs)) {
// Prepare the instruction
VMIGet emitable = new VMIGet();
emitable.qs = qs;
emitable.orIV(seekIV(qs));
// Put out a SCOPE
workingSim.exec.add(new VMIScope());
// Process inner block and add the get
try {
processCode(en);
workingSim.exec.add(emitable);
} catch (Exception e) {
// Stop an error unravelling here....
}
// Add the RSCOPE
workingSim.exec.add(new VMIRScope());
} else {
errBadAttribute(en.toString(), "qs", "get");
}
}
/**
* Emit a Header instruction.
*/
private void handleHeader(ElementNode en) {
String name = en.getAttribute("name");
String value = en.getAttribute("value");
if (!isValid(name)) {
errBadAttribute(en.toString(), "name", "header");
} else if (!isValid(value)) {
errBadAttribute(en.toString(), "value", "header");
} else {
VMIHeader emitable = new VMIHeader();
emitable.name = name;
emitable.value = value;
emitable.orIV(seekIV(name)||seekIV(value));
workingSim.exec.add(emitable);
}
}
/**
* Emit a NV instruction.
*/
private void handleNV(ElementNode en) {
String name = en.getAttribute("name");
String valueText = getText(en.getFirstChild());
if (!isValid(name)) {
errBadAttribute(en.toString(), "name", "nv");
} else if (!isValid(valueText)) {
valueText = "\n";
} else {
VMINV emitable = new VMINV();
emitable.name = name;
emitable.value = valueText;
emitable.orIV(seekIV(name)||seekIV(valueText));
workingSim.exec.add(emitable);
}
}
/**
* handle a block. easy enough. just scope it!.
*/
private void handleBlock(ElementNode en) {
// Put out a SCOPE
workingSim.exec.add(new VMIScope());
// Process inner block and add the get
try {
processCode(en);
} catch (Exception e) {
// Stop an error unravelling here....
}
// Add the RSCOPE
workingSim.exec.add(new VMIRScope());
}
/**
* Emit a Verify instruction.
*/
private void handleVerify(ElementNode en) {
String size = en.getAttribute("size");
String crc = en.getAttribute("crc");
VMIVerify emitable = new VMIVerify();
if (isValid(size)) {
try {
emitable.size = Integer.parseInt(size);
} catch (Exception e) {
errBadAttribute(en.toString(), "size", "verify");
return;
}
}
// Add a CRC instruction, if the attribute is specified.
if (isValid(crc)) {
try {
int val = Integer.parseInt(crc);
VMICrc eCRC = new VMICrc();
eCRC.expected = val;
workingSim.exec.add(eCRC);
} catch (Exception e) {
errBadAttribute(en.toString(), "crc", "verify");
return;
}
}
workingSim.exec.add(emitable);
// Handle any SEEK or EXEC children
try {
processCode(en);
} catch (Exception e) {
// Stop an error unravelling here....
}
}
/**
* Handle a seek.
*/
private void handleSeek(ElementNode en) {
String seekText = en.getAttribute("string");
if (!isValid(seekText)) {
errBadAttribute(en.toString(), "string", "seek");
} else {
VMISeek emitable = new VMISeek();
emitable.expected = seekText;
emitable.orIV(seekIV(seekText));
workingSim.exec.add(emitable);
}
}
/**
* Handle an Exec.
*/
private void handleExec(ElementNode en) {
// we don't care if the content is mangled or empty.
String content = getText(en.getFirstChild());
String invoke = en.getAttribute("invoke");
if (!isValid(invoke)) {
errBadAttribute(en.toString(), "invoke", "exec");
} else {
VMIExec emitable = new VMIExec();
emitable.invocation = invoke;
emitable.content = content;
emitable.orIV(seekIV(content)||seekIV(invoke));
workingSim.exec.add(emitable);
}
}
/**
* Handle an IF.
*
* Bounce out any exceptions, cause a screwed IF will spoil a
* parent scope.
*/
private void handleIf(ElementNode en) throws Exception {
String expression = en.getAttribute("e");
String value = en.getAttribute("value");
if (!isValid(expression)) {
errBadAttribute(en.toString(), "e", "if");
} else if (!isValid(value)) {
errBadAttribute(en.toString(), "value", "if");
} else {
VMIIf emitable = new VMIIf();
emitable.e = expression;
emitable.value = value;
emitable.orIV(seekIV(expression)||seekIV(value));
workingSim.exec.add(emitable);
// ^^^^ We'll fixup the target in a bit...
// Put out a SCOPE
workingSim.exec.add(new VMIScope());
// Process inner block and add the get
try {
processCode(en);
} catch (Exception e) {
// Stop inner scope unravellings here...
}
// Add the RSCOPE
workingSim.exec.add(new VMIRScope());
// Fixup the target
emitable.target = workingSim.exec.size(); // Points to where the NEXT intruction
// should be put...
}
}
/**
* Handle an For
*/
private void handleFor(ElementNode en) {
int target;
VMISet initSet = null;
String count = en.getAttribute("count");
String init = en.getAttribute("init");
if (!isValid(count)) {
errBadAttribute(en.toString(), "count", "for");
} else {
// Prep the FOR
VMIFor emitable = new VMIFor();
emitable.count = count;
emitable.orIV(seekIV(count));
// Prep the INIT
if (init != null) {
initSet = new VMISet();
initSet.value = init;
initSet.name = count;
initSet.orIV(seekIV(init)||seekIV(count));
}
// Put out a SCOPE
workingSim.exec.add(new VMIScope());
// Process inner block and add the get
try {
if (init != null) {
workingSim.exec.add(initSet);
}
// Prepare a jump back and Emit the FOR
VMIJump emitjump = new VMIJump();
emitjump.target = workingSim.exec.size();
workingSim.exec.add(emitable);
// Work the inner scope
processCode(en);
// Emit the jump and points the FOR right past it.
workingSim.exec.add(emitjump);
emitable.target = workingSim.exec.size();
} catch (Exception e) {
// Stop inner scope unravellings here...
}
// Add the RSCOPE
workingSim.exec.add(new VMIRScope());
}
}
/**
* Handle an WHILE.
*
* Bounce out any exceptions, cause a screwed IF will spoil a
* parent scope.
*/
private void handleWhile(ElementNode en) throws Exception {
String expression = en.getAttribute("e");
String value = en.getAttribute("value");
if (!isValid(expression)) {
errBadAttribute(en.toString(), "e", "while");
} else if (!isValid(value)) {
errBadAttribute(en.toString(), "value", "while");
} else {
// Prep the while
VMIWhile emitable = new VMIWhile();
emitable.e = expression;
emitable.value = value;
emitable.orIV(seekIV(expression)||seekIV(value));
// Emit a SCOPE
workingSim.exec.add(new VMIScope());
// Emit a NOP and point the while at it
emitable.target = workingSim.exec.size();
workingSim.exec.add(new VMINop());
// Process inner block
try {
processCode(en);
} catch (Exception e) {
// Stop inner scope unravellings here...
}
// Emit the WHILE and RSCOPE
workingSim.exec.add(emitable);
workingSim.exec.add(new VMIRScope());
}
}
// == ===============================================================================
// == = HELPERS =
// == ===============================================================================
/**
* See if a string contains an imbedded variable.
*
* It uses VMInstruction.IVToken as the delimiter.
*
* @param s the string to check.
* @return true if yes, otherwise false
*/
private boolean seekIV(String s) {
int sl = s.length() - 1;
for (int idx = 0; idx < sl; idx++) {
if ((s.charAt(idx) == VMInstruction.IVToken)&&
(s.charAt(idx+1) != VMInstruction.IVToken))
return true;
}
return false;
}
/**
* Valid string.
*
* Checks if the reference is not null and the srring contains characters.
*
* @param s the string to check.
* @return true if valid, otherwise false
*/
private boolean isValid(String s) {
if ((s == null)||(s.length() < 1)) return false;
else return true;
}
/**
* Translate a textual token into a numeric token.
*
* @param text token text.
* @return token numeric.
*/
private int translateToken(String text) {
// I'm going to let the parser try and optimize this...
//DEBUG
//System.out.println("XLATE token: [" + text + "]");
try {
switch(text.charAt(0)) {
case 'n': switch(text.charAt(1)) {
case 'a': return tokNAME;
case 'o': return tokNOTE;
case 'v': return tokNV;
default: return tokNULL;
}
case 'v': switch(text.charAt(3)) {
case 'i': return tokVERIFY;
case 's': return tokVERSION;
default: return tokNULL;
}
case 'w': switch(text.charAt(1)) {
case 'h': return tokWHILE;
case 'a': return tokWAIT;
default: return tokNULL;
}
case 'i': return tokIF;
case 's': switch(text.charAt(2)) {
case 't': return tokSET;
case 'e': return tokSEEK;
default: return tokNULL;
}
case 'f': return tokFOR;
case 'g': return tokGET;
case 'h': return tokHEADER;
case 'b': return tokBLOCK;
case 'a': return tokADD;
case 'e': return tokEXEC;
default: return tokNULL;
}
} catch (Exception e) { }
return tokNULL;
}
/**
* Get the text out of an XML node.
*
* @param cdn XML node.
* @return the text.
*/
private String getText(Node cdn) {
try {
if ((cdn.getNodeType() == Node.TEXT_NODE)||(cdn.getNodeType() != Node. CDATA_SECTION_NODE)) {
CharacterData cdnc = (CharacterData)cdn;
return cdnc.getData();
}
} catch (Exception e) { } // ignore. re are returning empty anyway
return null;
}
/**
* Get the text out of an XML node.
*
* @param where where it was bad.
* @param which which attribute was bad.
* @param tag which tag.
* @return the text.
*/
private void errBadAttribute(String where, String which, String tag) {
err.error("Invalid '" + which + "' attribute for <" + tag + ">. @" + where);
}
// --- INTERNAL CLASSES ---------------------------------------------------
// --- DEBUG METHODS ------------------------------------------------------
}