- /*
- * 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 javax.xml.transform.TransformerException;
- import org.apache.xalan.res.XSLMessages;
- import org.apache.xalan.templates.Constants;
- import org.apache.xalan.templates.ElemTemplate;
- import org.apache.xalan.templates.ElemTemplateElement;
- import org.apache.xml.utils.ObjectStack;
-
- /**
- * 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;
-
- TransformerImpl m_transformer;
-
- /**
- * 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;
- }
-
- /**
- * Constructor StackGuard
- *
- *
- * @param xslTemplate Current template node
- * @param sourceXML Source Node
- */
- public StackGuard(TransformerImpl transformerImpl)
- {
- m_transformer = transformerImpl;
- }
-
- /**
- * Overide equal method for StackGuard objects
- *
- *
- * @param obj StackGuard object to compare
- *
- * @return True if the given object matches this StackGuard object
- */
- public int countLikeTemplates(ElemTemplate templ, int pos)
- {
- ObjectStack elems = m_transformer.getCurrentTemplateElements();
- int count = 1;
- for (int i = pos-1; i >= 0; i--)
- {
- if((ElemTemplateElement)elems.elementAt(i) == templ)
- count++;
- }
-
- return count;
- }
-
-
- /**
- * Get the next named or match template down from and including
- * the given position.
- * @param pos the current index position in the stack.
- * @return null if no matched or named template found, otherwise
- * the next named or matched template at or below the position.
- */
- private ElemTemplate getNextMatchOrNamedTemplate(int pos)
- {
- ObjectStack elems = m_transformer.getCurrentTemplateElements();
- for (int i = pos; i >= 0; i--)
- {
- ElemTemplateElement elem = (ElemTemplateElement) elems.elementAt(i);
- if(null != elem)
- {
- if(elem.getXSLToken() == Constants.ELEMNAME_TEMPLATE)
- {
- return (ElemTemplate)elem;
- }
- }
- }
- return null;
- }
-
- /**
- * Check if we are in an infinite loop
- *
- *
- * @param guard Current StackGuard object (matching current template)
- *
- * @throws TransformerException
- */
- public void checkForInfinateLoop() throws TransformerException
- {
- int nTemplates = m_transformer.getCurrentTemplateElementsCount();
- if(nTemplates < m_recursionLimit)
- return;
-
- if(m_recursionLimit <= 0)
- return; // Safety check.
-
- // loop from the top index down to the recursion limit (I don't think
- // there's any need to go below that).
- for (int i = (nTemplates - 1); i >= m_recursionLimit; i--)
- {
- ElemTemplate template = getNextMatchOrNamedTemplate(i);
-
- if(null == template)
- break;
-
- int loopCount = countLikeTemplates(template, i);
-
- if (loopCount >= m_recursionLimit)
- {
- // throw new TransformerException("Template nesting too deep. nesting = "+loopCount+
- // ", template "+((null == template.getName()) ? "name = " : "match = ")+
- // ((null != template.getName()) ? template.getName().toString()
- // : template.getMatch().getPatternString()));
-
- String idIs = XSLMessages.createMessage(((null != template.getName()) ? "nameIs" : "matchPatternIs"), null);
- Object[] msgArgs = new Object[]{ new Integer(loopCount), idIs,
- ((null != template.getName()) ? template.getName().toString()
- : template.getMatch().getPatternString()) };
- String msg = XSLMessages.createMessage("recursionTooDeep", msgArgs);
-
- throw new TransformerException(msg);
- }
- }
- }
-
- }