RetroZilla/extensions/transformiix/source/xpath/LocationStep.cpp
2015-10-20 23:03:22 -04:00

329 lines
10 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is TransforMiiX XSLT processor code.
*
* The Initial Developer of the Original Code is
* The MITRE Corporation.
* Portions created by the Initial Developer are Copyright (C) 1999
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Keith Visco <kvisco@ziplink.net> (Original Author)
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/*
Implementation of an XPath LocationStep
*/
#include "Expr.h"
#include "txIXPathContext.h"
#include "txNodeSet.h"
//-----------------------------/
//- Virtual methods from Expr -/
//-----------------------------/
/**
* Evaluates this Expr based on the given context node and processor state
* @param context the context node for evaluation of this Expr
* @param ps the ProcessorState containing the stack information needed
* for evaluation
* @return the result of the evaluation
* @see Expr
**/
nsresult
LocationStep::evaluate(txIEvalContext* aContext, txAExprResult** aResult)
{
NS_ASSERTION(aContext, "internal error");
*aResult = nsnull;
nsRefPtr<txNodeSet> nodes;
nsresult rv = aContext->recycler()->getNodeSet(getter_AddRefs(nodes));
NS_ENSURE_SUCCESS(rv, rv);
txXPathTreeWalker walker(aContext->getContextNode());
switch (mAxisIdentifier) {
case ANCESTOR_AXIS:
{
if (!walker.moveToParent()) {
break;
}
// do not break here
}
case ANCESTOR_OR_SELF_AXIS:
{
nodes->setReverse();
do {
if (mNodeTest->matches(walker.getCurrentPosition(), aContext)) {
nodes->append(walker.getCurrentPosition());
}
} while (walker.moveToParent());
break;
}
case ATTRIBUTE_AXIS:
{
if (!walker.moveToFirstAttribute()) {
break;
}
do {
if (mNodeTest->matches(walker.getCurrentPosition(), aContext)) {
nodes->append(walker.getCurrentPosition());
}
} while (walker.moveToNextAttribute());
break;
}
case DESCENDANT_OR_SELF_AXIS:
{
if (mNodeTest->matches(walker.getCurrentPosition(), aContext)) {
nodes->append(walker.getCurrentPosition());
}
// do not break here
}
case DESCENDANT_AXIS:
{
fromDescendants(walker.getCurrentPosition(), aContext, nodes);
break;
}
case FOLLOWING_AXIS:
{
if (txXPathNodeUtils::isAttribute(walker.getCurrentPosition())) {
walker.moveToParent();
fromDescendants(walker.getCurrentPosition(), aContext, nodes);
}
PRBool cont = PR_TRUE;
while (!walker.moveToNextSibling()) {
if (!walker.moveToParent()) {
cont = PR_FALSE;
break;
}
}
while (cont) {
if (mNodeTest->matches(walker.getCurrentPosition(), aContext)) {
nodes->append(walker.getCurrentPosition());
}
fromDescendants(walker.getCurrentPosition(), aContext, nodes);
while (!walker.moveToNextSibling()) {
if (!walker.moveToParent()) {
cont = PR_FALSE;
break;
}
}
}
break;
}
case FOLLOWING_SIBLING_AXIS:
{
while (walker.moveToNextSibling()) {
if (mNodeTest->matches(walker.getCurrentPosition(), aContext)) {
nodes->append(walker.getCurrentPosition());
}
}
break;
}
case NAMESPACE_AXIS: //-- not yet implemented
#if 0
// XXX DEBUG OUTPUT
cout << "namespace axis not yet implemented"<<endl;
#endif
break;
case PARENT_AXIS :
{
if (walker.moveToParent() &&
mNodeTest->matches(walker.getCurrentPosition(), aContext)) {
nodes->append(walker.getCurrentPosition());
}
break;
}
case PRECEDING_AXIS:
{
nodes->setReverse();
PRBool cont = PR_TRUE;
while (!walker.moveToPreviousSibling()) {
if (!walker.moveToParent()) {
cont = PR_FALSE;
break;
}
}
while (cont) {
fromDescendantsRev(walker.getCurrentPosition(), aContext, nodes);
if (mNodeTest->matches(walker.getCurrentPosition(), aContext)) {
nodes->append(walker.getCurrentPosition());
}
while (!walker.moveToPreviousSibling()) {
if (!walker.moveToParent()) {
cont = PR_FALSE;
break;
}
}
}
break;
}
case PRECEDING_SIBLING_AXIS:
{
nodes->setReverse();
while (walker.moveToPreviousSibling()) {
if (mNodeTest->matches(walker.getCurrentPosition(), aContext)) {
nodes->append(walker.getCurrentPosition());
}
}
break;
}
case SELF_AXIS:
{
if (mNodeTest->matches(walker.getCurrentPosition(), aContext)) {
nodes->append(walker.getCurrentPosition());
}
break;
}
default: // Children Axis
{
if (!walker.moveToFirstChild()) {
break;
}
do {
if (mNodeTest->matches(walker.getCurrentPosition(), aContext)) {
nodes->append(walker.getCurrentPosition());
}
} while (walker.moveToNextSibling());
break;
}
}
// Apply predicates
if (!isEmpty()) {
rv = evaluatePredicates(nodes, aContext);
NS_ENSURE_SUCCESS(rv, rv);
}
nodes->unsetReverse();
NS_ADDREF(*aResult = nodes);
return NS_OK;
}
void LocationStep::fromDescendants(const txXPathNode& aNode,
txIMatchContext* aCs,
txNodeSet* aNodes)
{
txXPathTreeWalker walker(aNode);
if (!walker.moveToFirstChild()) {
return;
}
do {
const txXPathNode& child = walker.getCurrentPosition();
if (mNodeTest->matches(child, aCs)) {
aNodes->append(child);
}
fromDescendants(child, aCs, aNodes);
} while (walker.moveToNextSibling());
}
void LocationStep::fromDescendantsRev(const txXPathNode& aNode,
txIMatchContext* aCs,
txNodeSet* aNodes)
{
txXPathTreeWalker walker(aNode);
if (!walker.moveToLastChild()) {
return;
}
do {
const txXPathNode& child = walker.getCurrentPosition();
fromDescendantsRev(child, aCs, aNodes);
if (mNodeTest->matches(child, aCs)) {
aNodes->append(child);
}
} while (walker.moveToPreviousSibling());
}
#ifdef TX_TO_STRING
void
LocationStep::toString(nsAString& str)
{
switch (mAxisIdentifier) {
case ANCESTOR_AXIS :
str.AppendLiteral("ancestor::");
break;
case ANCESTOR_OR_SELF_AXIS :
str.AppendLiteral("ancestor-or-self::");
break;
case ATTRIBUTE_AXIS:
str.Append(PRUnichar('@'));
break;
case DESCENDANT_AXIS:
str.AppendLiteral("descendant::");
break;
case DESCENDANT_OR_SELF_AXIS:
str.AppendLiteral("descendant-or-self::");
break;
case FOLLOWING_AXIS :
str.AppendLiteral("following::");
break;
case FOLLOWING_SIBLING_AXIS:
str.AppendLiteral("following-sibling::");
break;
case NAMESPACE_AXIS:
str.AppendLiteral("namespace::");
break;
case PARENT_AXIS :
str.AppendLiteral("parent::");
break;
case PRECEDING_AXIS :
str.AppendLiteral("preceding::");
break;
case PRECEDING_SIBLING_AXIS :
str.AppendLiteral("preceding-sibling::");
break;
case SELF_AXIS :
str.AppendLiteral("self::");
break;
default:
break;
}
NS_ASSERTION(mNodeTest, "mNodeTest is null, that's verboten");
mNodeTest->toString(str);
PredicateList::toString(str);
}
#endif