| /* |
| * The Apache Software License, Version 1.1 |
| * |
| * |
| * Copyright (c) 1999 The Apache Software Foundation. All rights |
| * reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * 3. The end-user documentation included with the redistribution, |
| * if any, must include the following acknowledgment: |
| * "This product includes software developed by the |
| * Apache Software Foundation (http://www.apache.org/)." |
| * Alternately, this acknowledgment may appear in the software itself, |
| * if and wherever such third-party acknowledgments normally appear. |
| * |
| * 4. The names "Xalan" and "Apache Software Foundation" must |
| * not be used to endorse or promote products derived from this |
| * software without prior written permission. For written |
| * permission, please contact apache@apache.org. |
| * |
| * 5. Products derived from this software may not be called "Apache", |
| * nor may "Apache" appear in their name, without prior written |
| * permission of the Apache Software Foundation. |
| * |
| * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED |
| * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR |
| * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF |
| * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * ==================================================================== |
| * |
| * This software consists of voluntary contributions made by many |
| * individuals on behalf of the Apache Software Foundation and was |
| * originally based on software copyright (c) 1999, Lotus |
| * Development Corporation., http://www.lotus.com. For more |
| * information on the Apache Software Foundation, please see |
| * <http://www.apache.org/>. |
| */ |
| package org.apache.xalan.transformer; |
| |
| //import org.w3c.dom.Node; |
| //import org.w3c.dom.Text; |
| //import org.w3c.dom.Element; |
| import org.apache.xml.dtm.DTM; |
| |
| import java.io.PrintWriter; |
| import java.io.StringWriter; |
| |
| import javax.xml.transform.TransformerException; |
| |
| import org.apache.xalan.templates.ElemTemplateElement; |
| |
| /** |
| * Class to guard against recursion getting too deep. |
| */ |
| public class StackGuard |
| { |
| |
| /** |
| * Used for infinite loop check. If the value is -1, do not |
| * check for infinite loops. Anyone who wants to enable that |
| * check should change the value of this variable to be the |
| * level of recursion that they want to check. Be careful setting |
| * this variable, if the number is too low, it may report an |
| * infinite loop situation, when there is none. |
| * Post version 1.0.0, we'll make this a runtime feature. |
| */ |
| public static int m_recursionLimit = -1; |
| |
| /** |
| * Get the recursion limit. |
| * Used for infinite loop check. If the value is -1, do not |
| * check for infinite loops. Anyone who wants to enable that |
| * check should change the value of this variable to be the |
| * level of recursion that they want to check. Be careful setting |
| * this variable, if the number is too low, it may report an |
| * infinite loop situation, when there is none. |
| * Post version 1.0.0, we'll make this a runtime feature. |
| * |
| * @return The recursion limit. |
| */ |
| public int getRecursionLimit() |
| { |
| return m_recursionLimit; |
| } |
| |
| /** |
| * Set the recursion limit. |
| * Used for infinite loop check. If the value is -1, do not |
| * check for infinite loops. Anyone who wants to enable that |
| * check should change the value of this variable to be the |
| * level of recursion that they want to check. Be careful setting |
| * this variable, if the number is too low, it may report an |
| * infinite loop situation, when there is none. |
| * Post version 1.0.0, we'll make this a runtime feature. |
| * |
| * @param limit The recursion limit. |
| */ |
| public void setRecursionLimit(int limit) |
| { |
| m_recursionLimit = limit; |
| } |
| |
| /** Stylesheet Template node */ |
| ElemTemplateElement m_xslRule; |
| |
| /** Source node */ |
| int m_sourceXML; |
| |
| /** Stack where ElemTempalteElements will be pushed */ |
| java.util.Stack stack = new java.util.Stack(); |
| |
| /** |
| * Constructor StackGuard |
| * |
| */ |
| public StackGuard(){} |
| |
| /** |
| * Constructor StackGuard |
| * |
| * |
| * @param xslTemplate Current template node |
| * @param sourceXML Source Node |
| */ |
| public StackGuard(ElemTemplateElement xslTemplate, int sourceXML) |
| { |
| m_xslRule = xslTemplate; |
| m_sourceXML = sourceXML; |
| } |
| |
| /** |
| * Overide equal method for StackGuard objects |
| * |
| * |
| * @param obj StackGuard object to compare |
| * |
| * @return True if the given object matches this StackGuard object |
| */ |
| public boolean equals(Object obj) |
| { |
| |
| if (((StackGuard) obj).m_xslRule.equals(m_xslRule) |
| && ((StackGuard) obj).m_sourceXML == m_sourceXML) |
| { |
| return true; |
| } |
| |
| return false; |
| } |
| |
| /** |
| * Output diagnostics if in an infinite loop |
| * |
| * |
| * @param pw Non-null PrintWriter instance to use |
| */ |
| public void print(PrintWriter pw) |
| { |
| |
| // for the moment, these diagnostics are really bad... |
| // %DTBD% We need an execution context. |
| // if (m_sourceXML instanceof Text) |
| // { |
| // Text tx = (Text) m_sourceXML; |
| // |
| // pw.println(tx.getData()); |
| // } |
| // else if (m_sourceXML instanceof Element) |
| // { |
| // Element elem = (Element) m_sourceXML; |
| // |
| // pw.println(elem.getNodeName()); |
| // } |
| } |
| |
| /** |
| * Check if we are in an infinite loop |
| * |
| * |
| * @param guard Current StackGuard object (matching current template) |
| * |
| * @throws TransformerException |
| */ |
| public void checkForInfinateLoop(StackGuard guard) throws TransformerException |
| { |
| |
| int nRules = stack.size(); |
| int loopCount = 0; |
| |
| for (int i = (nRules - 1); i >= 0; i--) |
| { |
| if (stack.elementAt(i).equals(guard)) |
| { |
| loopCount++; |
| } |
| |
| if (loopCount >= m_recursionLimit) |
| { |
| |
| // Print out really bad diagnostics. |
| StringWriter sw = new StringWriter(); |
| PrintWriter pw = new PrintWriter(sw); |
| |
| pw.println("Infinite loop diagnosed! Stack trace:"); |
| |
| int k; |
| |
| for (k = 0; k < nRules; k++) |
| { |
| pw.println("Source Elem #" + k + " "); |
| |
| StackGuard guardOnStack = (StackGuard) stack.elementAt(i); |
| |
| guardOnStack.print(pw); |
| } |
| |
| pw.println("Source Elem #" + k + " "); |
| guard.print(pw); |
| pw.println("End of infinite loop diagnosis."); |
| |
| throw new TransformerException(sw.getBuffer().toString()); |
| } |
| } |
| } |
| |
| /** |
| * Push in a StackGuard object mathing given template |
| * |
| * |
| * @param xslTemplate Current template being processed |
| * @param sourceXML Current Source Node |
| * |
| * @throws TransformerException |
| */ |
| public void push(ElemTemplateElement xslTemplate, int sourceXML) |
| throws TransformerException |
| { |
| |
| StackGuard guard = new StackGuard(xslTemplate, sourceXML); |
| |
| checkForInfinateLoop(guard); |
| stack.push(guard); |
| } |
| |
| /** |
| * Pop out Stack of StackGuard objects |
| * |
| */ |
| public void pop() |
| { |
| stack.pop(); |
| } |
| } |