1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/dom/xslt/xpath/txPathExpr.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,253 @@
1.4 +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#include "txExpr.h"
1.10 +#include "txNodeSet.h"
1.11 +#include "txNodeSetContext.h"
1.12 +#include "txSingleNodeContext.h"
1.13 +#include "txXMLUtils.h"
1.14 +#include "txXPathTreeWalker.h"
1.15 +
1.16 + //------------/
1.17 + //- PathExpr -/
1.18 +//------------/
1.19 +
1.20 +/**
1.21 + * Adds the Expr to this PathExpr
1.22 + * @param expr the Expr to add to this PathExpr
1.23 +**/
1.24 +nsresult
1.25 +PathExpr::addExpr(Expr* aExpr, PathOperator aPathOp)
1.26 +{
1.27 + NS_ASSERTION(!mItems.IsEmpty() || aPathOp == RELATIVE_OP,
1.28 + "First step has to be relative in PathExpr");
1.29 + PathExprItem* pxi = mItems.AppendElement();
1.30 + if (!pxi) {
1.31 + return NS_ERROR_OUT_OF_MEMORY;
1.32 + }
1.33 + pxi->expr = aExpr;
1.34 + pxi->pathOp = aPathOp;
1.35 +
1.36 + return NS_OK;
1.37 +}
1.38 +
1.39 + //-----------------------------/
1.40 + //- Virtual methods from Expr -/
1.41 +//-----------------------------/
1.42 +
1.43 +/**
1.44 + * Evaluates this Expr based on the given context node and processor state
1.45 + * @param context the context node for evaluation of this Expr
1.46 + * @param ps the ContextState containing the stack information needed
1.47 + * for evaluation
1.48 + * @return the result of the evaluation
1.49 +**/
1.50 +nsresult
1.51 +PathExpr::evaluate(txIEvalContext* aContext, txAExprResult** aResult)
1.52 +{
1.53 + *aResult = nullptr;
1.54 +
1.55 + // We need to evaluate the first step with the current context since it
1.56 + // can depend on the context size and position. For example:
1.57 + // key('books', concat('book', position()))
1.58 + nsRefPtr<txAExprResult> res;
1.59 + nsresult rv = mItems[0].expr->evaluate(aContext, getter_AddRefs(res));
1.60 + NS_ENSURE_SUCCESS(rv, rv);
1.61 +
1.62 + NS_ENSURE_TRUE(res->getResultType() == txAExprResult::NODESET,
1.63 + NS_ERROR_XSLT_NODESET_EXPECTED);
1.64 +
1.65 + nsRefPtr<txNodeSet> nodes = static_cast<txNodeSet*>
1.66 + (static_cast<txAExprResult*>
1.67 + (res));
1.68 + if (nodes->isEmpty()) {
1.69 + res.swap(*aResult);
1.70 +
1.71 + return NS_OK;
1.72 + }
1.73 + res = nullptr; // To allow recycling
1.74 +
1.75 + // Evaluate remaining steps
1.76 + uint32_t i, len = mItems.Length();
1.77 + for (i = 1; i < len; ++i) {
1.78 + PathExprItem& pxi = mItems[i];
1.79 + nsRefPtr<txNodeSet> tmpNodes;
1.80 + txNodeSetContext eContext(nodes, aContext);
1.81 + while (eContext.hasNext()) {
1.82 + eContext.next();
1.83 +
1.84 + nsRefPtr<txNodeSet> resNodes;
1.85 + if (pxi.pathOp == DESCENDANT_OP) {
1.86 + rv = aContext->recycler()->getNodeSet(getter_AddRefs(resNodes));
1.87 + NS_ENSURE_SUCCESS(rv, rv);
1.88 +
1.89 + rv = evalDescendants(pxi.expr, eContext.getContextNode(),
1.90 + &eContext, resNodes);
1.91 + NS_ENSURE_SUCCESS(rv, rv);
1.92 + }
1.93 + else {
1.94 + nsRefPtr<txAExprResult> res;
1.95 + rv = pxi.expr->evaluate(&eContext, getter_AddRefs(res));
1.96 + NS_ENSURE_SUCCESS(rv, rv);
1.97 +
1.98 + if (res->getResultType() != txAExprResult::NODESET) {
1.99 + //XXX ErrorReport: report nonnodeset error
1.100 + return NS_ERROR_XSLT_NODESET_EXPECTED;
1.101 + }
1.102 + resNodes = static_cast<txNodeSet*>
1.103 + (static_cast<txAExprResult*>
1.104 + (res));
1.105 + }
1.106 +
1.107 + if (tmpNodes) {
1.108 + if (!resNodes->isEmpty()) {
1.109 + nsRefPtr<txNodeSet> oldSet;
1.110 + oldSet.swap(tmpNodes);
1.111 + rv = aContext->recycler()->
1.112 + getNonSharedNodeSet(oldSet, getter_AddRefs(tmpNodes));
1.113 + NS_ENSURE_SUCCESS(rv, rv);
1.114 +
1.115 + oldSet.swap(resNodes);
1.116 + rv = aContext->recycler()->
1.117 + getNonSharedNodeSet(oldSet, getter_AddRefs(resNodes));
1.118 + NS_ENSURE_SUCCESS(rv, rv);
1.119 +
1.120 + tmpNodes->addAndTransfer(resNodes);
1.121 + }
1.122 + }
1.123 + else {
1.124 + tmpNodes = resNodes;
1.125 + }
1.126 + }
1.127 + nodes = tmpNodes;
1.128 + if (nodes->isEmpty()) {
1.129 + break;
1.130 + }
1.131 + }
1.132 +
1.133 + *aResult = nodes;
1.134 + NS_ADDREF(*aResult);
1.135 +
1.136 + return NS_OK;
1.137 +} //-- evaluate
1.138 +
1.139 +/**
1.140 + * Selects from the descendants of the context node
1.141 + * all nodes that match the Expr
1.142 +**/
1.143 +nsresult
1.144 +PathExpr::evalDescendants(Expr* aStep, const txXPathNode& aNode,
1.145 + txIMatchContext* aContext, txNodeSet* resNodes)
1.146 +{
1.147 + txSingleNodeContext eContext(aNode, aContext);
1.148 + nsRefPtr<txAExprResult> res;
1.149 + nsresult rv = aStep->evaluate(&eContext, getter_AddRefs(res));
1.150 + NS_ENSURE_SUCCESS(rv, rv);
1.151 +
1.152 + if (res->getResultType() != txAExprResult::NODESET) {
1.153 + //XXX ErrorReport: report nonnodeset error
1.154 + return NS_ERROR_XSLT_NODESET_EXPECTED;
1.155 + }
1.156 +
1.157 + txNodeSet* oldSet = static_cast<txNodeSet*>
1.158 + (static_cast<txAExprResult*>(res));
1.159 + nsRefPtr<txNodeSet> newSet;
1.160 + rv = aContext->recycler()->getNonSharedNodeSet(oldSet,
1.161 + getter_AddRefs(newSet));
1.162 + NS_ENSURE_SUCCESS(rv, rv);
1.163 +
1.164 + resNodes->addAndTransfer(newSet);
1.165 +
1.166 + bool filterWS = aContext->isStripSpaceAllowed(aNode);
1.167 +
1.168 + txXPathTreeWalker walker(aNode);
1.169 + if (!walker.moveToFirstChild()) {
1.170 + return NS_OK;
1.171 + }
1.172 +
1.173 + do {
1.174 + const txXPathNode& node = walker.getCurrentPosition();
1.175 + if (!(filterWS && txXPathNodeUtils::isText(node) &&
1.176 + txXPathNodeUtils::isWhitespace(node))) {
1.177 + rv = evalDescendants(aStep, node, aContext, resNodes);
1.178 + NS_ENSURE_SUCCESS(rv, rv);
1.179 + }
1.180 + } while (walker.moveToNextSibling());
1.181 +
1.182 + return NS_OK;
1.183 +} //-- evalDescendants
1.184 +
1.185 +Expr::ExprType
1.186 +PathExpr::getType()
1.187 +{
1.188 + return PATH_EXPR;
1.189 +}
1.190 +
1.191 +TX_IMPL_EXPR_STUBS_BASE(PathExpr, NODESET_RESULT)
1.192 +
1.193 +Expr*
1.194 +PathExpr::getSubExprAt(uint32_t aPos)
1.195 +{
1.196 + return aPos < mItems.Length() ? mItems[aPos].expr.get() : nullptr;
1.197 +}
1.198 +void
1.199 +PathExpr::setSubExprAt(uint32_t aPos, Expr* aExpr)
1.200 +{
1.201 + NS_ASSERTION(aPos < mItems.Length(), "setting bad subexpression index");
1.202 + mItems[aPos].expr.forget();
1.203 + mItems[aPos].expr = aExpr;
1.204 +}
1.205 +
1.206 +
1.207 +bool
1.208 +PathExpr::isSensitiveTo(ContextSensitivity aContext)
1.209 +{
1.210 + if (mItems[0].expr->isSensitiveTo(aContext)) {
1.211 + return true;
1.212 + }
1.213 +
1.214 + // We're creating a new node/nodeset so we can ignore those bits.
1.215 + Expr::ContextSensitivity context =
1.216 + aContext & ~(Expr::NODE_CONTEXT | Expr::NODESET_CONTEXT);
1.217 + if (context == NO_CONTEXT) {
1.218 + return false;
1.219 + }
1.220 +
1.221 + uint32_t i, len = mItems.Length();
1.222 + for (i = 0; i < len; ++i) {
1.223 + NS_ASSERTION(!mItems[i].expr->isSensitiveTo(Expr::NODESET_CONTEXT),
1.224 + "Step cannot depend on nodeset-context");
1.225 + if (mItems[i].expr->isSensitiveTo(context)) {
1.226 + return true;
1.227 + }
1.228 + }
1.229 +
1.230 + return false;
1.231 +}
1.232 +
1.233 +#ifdef TX_TO_STRING
1.234 +void
1.235 +PathExpr::toString(nsAString& dest)
1.236 +{
1.237 + if (!mItems.IsEmpty()) {
1.238 + NS_ASSERTION(mItems[0].pathOp == RELATIVE_OP,
1.239 + "First step should be relative");
1.240 + mItems[0].expr->toString(dest);
1.241 + }
1.242 +
1.243 + uint32_t i, len = mItems.Length();
1.244 + for (i = 1; i < len; ++i) {
1.245 + switch (mItems[i].pathOp) {
1.246 + case DESCENDANT_OP:
1.247 + dest.AppendLiteral("//");
1.248 + break;
1.249 + case RELATIVE_OP:
1.250 + dest.Append(char16_t('/'));
1.251 + break;
1.252 + }
1.253 + mItems[i].expr->toString(dest);
1.254 + }
1.255 +}
1.256 +#endif
