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Diffstat (limited to '')
| -rw-r--r-- | dom/xslt/xpath/txExprParser.cpp | 879 |
1 files changed, 879 insertions, 0 deletions
diff --git a/dom/xslt/xpath/txExprParser.cpp b/dom/xslt/xpath/txExprParser.cpp new file mode 100644 index 0000000000..d59b761d37 --- /dev/null +++ b/dom/xslt/xpath/txExprParser.cpp @@ -0,0 +1,879 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/** + * ExprParser + * This class is used to parse XSL Expressions + * @see ExprLexer + **/ + +#include "txExprParser.h" + +#include <utility> + +#include "mozilla/UniquePtrExtensions.h" +#include "nsError.h" +#include "nsGkAtoms.h" +#include "txExpr.h" +#include "txExprLexer.h" +#include "txIXPathContext.h" +#include "txStack.h" +#include "txStringUtils.h" +#include "txXPathNode.h" +#include "txXPathOptimizer.h" + +using mozilla::MakeUnique; +using mozilla::UniquePtr; +using mozilla::Unused; +using mozilla::WrapUnique; + +/** + * Creates an Attribute Value Template using the given value + * This should move to XSLProcessor class + */ +nsresult txExprParser::createAVT(const nsAString& aAttrValue, + txIParseContext* aContext, Expr** aResult) { + *aResult = nullptr; + nsresult rv = NS_OK; + UniquePtr<Expr> expr; + FunctionCall* concat = nullptr; + + nsAutoString literalString; + bool inExpr = false; + nsAString::const_char_iterator iter, start, end, avtStart; + aAttrValue.BeginReading(iter); + aAttrValue.EndReading(end); + avtStart = iter; + + while (iter != end) { + // Every iteration through this loop parses either a literal section + // or an expression + start = iter; + UniquePtr<Expr> newExpr; + if (!inExpr) { + // Parse literal section + literalString.Truncate(); + while (iter != end) { + char16_t q = *iter; + if (q == '{' || q == '}') { + // Store what we've found so far and set a new |start| to + // skip the (first) brace + literalString.Append(Substring(start, iter)); + start = ++iter; + // Unless another brace follows we've found the start of + // an expression (in case of '{') or an unbalanced brace + // (in case of '}') + if (iter == end || *iter != q) { + if (q == '}') { + aContext->SetErrorOffset(iter - avtStart); + return NS_ERROR_XPATH_UNBALANCED_CURLY_BRACE; + } + + inExpr = true; + break; + } + // We found a second brace, let that be part of the next + // literal section being parsed and continue looping + } + ++iter; + } + + if (start == iter && literalString.IsEmpty()) { + // Restart the loop since we didn't create an expression + continue; + } + newExpr = + MakeUnique<txLiteralExpr>(literalString + Substring(start, iter)); + } else { + // Parse expressions, iter is already past the initial '{' when + // we get here. + while (iter != end) { + if (*iter == '}') { + rv = createExprInternal(Substring(start, iter), start - avtStart, + aContext, getter_Transfers(newExpr)); + NS_ENSURE_SUCCESS(rv, rv); + + inExpr = false; + ++iter; // skip closing '}' + break; + } else if (*iter == '\'' || *iter == '"') { + char16_t q = *iter; + while (++iter != end && *iter != q) { + } /* do nothing */ + if (iter == end) { + break; + } + } + ++iter; + } + + if (inExpr) { + aContext->SetErrorOffset(start - avtStart); + return NS_ERROR_XPATH_UNBALANCED_CURLY_BRACE; + } + } + + // Add expression, create a concat() call if necessary + if (!expr) { + expr = std::move(newExpr); + } else { + if (!concat) { + concat = new txCoreFunctionCall(txCoreFunctionCall::CONCAT); + rv = concat->addParam(expr.release()); + expr = WrapUnique(concat); + NS_ENSURE_SUCCESS(rv, rv); + } + + rv = concat->addParam(newExpr.release()); + NS_ENSURE_SUCCESS(rv, rv); + } + } + + if (inExpr) { + aContext->SetErrorOffset(iter - avtStart); + return NS_ERROR_XPATH_UNBALANCED_CURLY_BRACE; + } + + if (!expr) { + expr = MakeUnique<txLiteralExpr>(u""_ns); + } + + *aResult = expr.release(); + + return NS_OK; +} + +nsresult txExprParser::createExprInternal(const nsAString& aExpression, + uint32_t aSubStringPos, + txIParseContext* aContext, + Expr** aExpr) { + NS_ENSURE_ARG_POINTER(aExpr); + *aExpr = nullptr; + txExprLexer lexer; + nsresult rv = lexer.parse(aExpression); + if (NS_FAILED(rv)) { + nsAString::const_char_iterator start; + aExpression.BeginReading(start); + aContext->SetErrorOffset(lexer.mPosition - start + aSubStringPos); + return rv; + } + UniquePtr<Expr> expr; + rv = createExpr(lexer, aContext, getter_Transfers(expr)); + if (NS_SUCCEEDED(rv) && lexer.peek()->mType != Token::END) { + rv = NS_ERROR_XPATH_BINARY_EXPECTED; + } + if (NS_FAILED(rv)) { + nsAString::const_char_iterator start; + aExpression.BeginReading(start); + aContext->SetErrorOffset(lexer.peek()->mStart - start + aSubStringPos); + + return rv; + } + + txXPathOptimizer optimizer; + Expr* newExpr = nullptr; + rv = optimizer.optimize(expr.get(), &newExpr); + NS_ENSURE_SUCCESS(rv, rv); + + *aExpr = newExpr ? newExpr : expr.release(); + + return NS_OK; +} + +/** + * Private Methods + */ + +/** + * Creates a binary Expr for the given operator + */ +nsresult txExprParser::createBinaryExpr(UniquePtr<Expr>& left, + UniquePtr<Expr>& right, Token* op, + Expr** aResult) { + NS_ASSERTION(op, "internal error"); + *aResult = nullptr; + + Expr* expr = nullptr; + switch (op->mType) { + //-- math ops + case Token::ADDITION_OP: + expr = new txNumberExpr(left.get(), right.get(), txNumberExpr::ADD); + break; + case Token::SUBTRACTION_OP: + expr = new txNumberExpr(left.get(), right.get(), txNumberExpr::SUBTRACT); + break; + case Token::DIVIDE_OP: + expr = new txNumberExpr(left.get(), right.get(), txNumberExpr::DIVIDE); + break; + case Token::MODULUS_OP: + expr = new txNumberExpr(left.get(), right.get(), txNumberExpr::MODULUS); + break; + case Token::MULTIPLY_OP: + expr = new txNumberExpr(left.get(), right.get(), txNumberExpr::MULTIPLY); + break; + + //-- case boolean ops + case Token::AND_OP: + expr = new BooleanExpr(left.get(), right.get(), BooleanExpr::AND); + break; + case Token::OR_OP: + expr = new BooleanExpr(left.get(), right.get(), BooleanExpr::OR); + break; + + //-- equality ops + case Token::EQUAL_OP: + expr = new RelationalExpr(left.get(), right.get(), RelationalExpr::EQUAL); + break; + case Token::NOT_EQUAL_OP: + expr = new RelationalExpr(left.get(), right.get(), + RelationalExpr::NOT_EQUAL); + break; + + //-- relational ops + case Token::LESS_THAN_OP: + expr = new RelationalExpr(left.get(), right.get(), + RelationalExpr::LESS_THAN); + break; + case Token::GREATER_THAN_OP: + expr = new RelationalExpr(left.get(), right.get(), + RelationalExpr::GREATER_THAN); + break; + case Token::LESS_OR_EQUAL_OP: + expr = new RelationalExpr(left.get(), right.get(), + RelationalExpr::LESS_OR_EQUAL); + break; + case Token::GREATER_OR_EQUAL_OP: + expr = new RelationalExpr(left.get(), right.get(), + RelationalExpr::GREATER_OR_EQUAL); + break; + + default: + MOZ_ASSERT_UNREACHABLE("operator tokens should be already checked"); + return NS_ERROR_UNEXPECTED; + } + NS_ENSURE_TRUE(expr, NS_ERROR_OUT_OF_MEMORY); + + Unused << left.release(); + Unused << right.release(); + + *aResult = expr; + return NS_OK; +} + +nsresult txExprParser::createExpr(txExprLexer& lexer, txIParseContext* aContext, + Expr** aResult) { + *aResult = nullptr; + + nsresult rv = NS_OK; + bool done = false; + + UniquePtr<Expr> expr; + + txStack exprs; + txStack ops; + + while (!done) { + uint16_t negations = 0; + while (lexer.peek()->mType == Token::SUBTRACTION_OP) { + negations++; + lexer.nextToken(); + } + + rv = createUnionExpr(lexer, aContext, getter_Transfers(expr)); + if (NS_FAILED(rv)) { + break; + } + + if (negations > 0) { + if (negations % 2 == 0) { + FunctionCall* fcExpr = + new txCoreFunctionCall(txCoreFunctionCall::NUMBER); + + rv = fcExpr->addParam(expr.get()); + if (NS_FAILED(rv)) return rv; + Unused << expr.release(); + expr = WrapUnique(fcExpr); + } else { + expr = MakeUnique<UnaryExpr>(expr.release()); + } + } + + short tokPrecedence = precedence(lexer.peek()); + if (tokPrecedence != 0) { + Token* tok = lexer.nextToken(); + while (!exprs.isEmpty() && + tokPrecedence <= precedence(static_cast<Token*>(ops.peek()))) { + // can't use expr as argument due to order of evaluation + UniquePtr<Expr> left(static_cast<Expr*>(exprs.pop())); + UniquePtr<Expr> right(std::move(expr)); + rv = createBinaryExpr(left, right, static_cast<Token*>(ops.pop()), + getter_Transfers(expr)); + if (NS_FAILED(rv)) { + done = true; + break; + } + } + exprs.push(expr.release()); + ops.push(tok); + } else { + done = true; + } + } + + while (NS_SUCCEEDED(rv) && !exprs.isEmpty()) { + UniquePtr<Expr> left(static_cast<Expr*>(exprs.pop())); + UniquePtr<Expr> right(std::move(expr)); + rv = createBinaryExpr(left, right, static_cast<Token*>(ops.pop()), + getter_Transfers(expr)); + } + // clean up on error + while (!exprs.isEmpty()) { + delete static_cast<Expr*>(exprs.pop()); + } + NS_ENSURE_SUCCESS(rv, rv); + + *aResult = expr.release(); + return NS_OK; +} + +nsresult txExprParser::createFilterOrStep(txExprLexer& lexer, + txIParseContext* aContext, + Expr** aResult) { + *aResult = nullptr; + + nsresult rv = NS_OK; + Token* tok = lexer.peek(); + + UniquePtr<Expr> expr; + switch (tok->mType) { + case Token::FUNCTION_NAME_AND_PAREN: + rv = createFunctionCall(lexer, aContext, getter_Transfers(expr)); + NS_ENSURE_SUCCESS(rv, rv); + break; + case Token::VAR_REFERENCE: + lexer.nextToken(); + { + RefPtr<nsAtom> prefix, lName; + int32_t nspace; + nsresult rv = resolveQName(tok->Value(), getter_AddRefs(prefix), + aContext, getter_AddRefs(lName), nspace); + NS_ENSURE_SUCCESS(rv, rv); + expr = MakeUnique<VariableRefExpr>(prefix, lName, nspace); + } + break; + case Token::L_PAREN: + lexer.nextToken(); + rv = createExpr(lexer, aContext, getter_Transfers(expr)); + NS_ENSURE_SUCCESS(rv, rv); + + if (lexer.peek()->mType != Token::R_PAREN) { + return NS_ERROR_XPATH_PAREN_EXPECTED; + } + lexer.nextToken(); + break; + case Token::LITERAL: + lexer.nextToken(); + expr = MakeUnique<txLiteralExpr>(tok->Value()); + break; + case Token::NUMBER: { + lexer.nextToken(); + expr = MakeUnique<txLiteralExpr>(txDouble::toDouble(tok->Value())); + break; + } + default: + return createLocationStep(lexer, aContext, aResult); + } + + if (lexer.peek()->mType == Token::L_BRACKET) { + UniquePtr<FilterExpr> filterExpr(new FilterExpr(expr.get())); + + Unused << expr.release(); + + //-- handle predicates + rv = parsePredicates(filterExpr.get(), lexer, aContext); + NS_ENSURE_SUCCESS(rv, rv); + expr = std::move(filterExpr); + } + + *aResult = expr.release(); + return NS_OK; +} + +nsresult txExprParser::createFunctionCall(txExprLexer& lexer, + txIParseContext* aContext, + Expr** aResult) { + *aResult = nullptr; + + UniquePtr<FunctionCall> fnCall; + + Token* tok = lexer.nextToken(); + NS_ASSERTION(tok->mType == Token::FUNCTION_NAME_AND_PAREN, + "FunctionCall expected"); + + //-- compare function names + RefPtr<nsAtom> prefix, lName; + int32_t namespaceID; + nsresult rv = resolveQName(tok->Value(), getter_AddRefs(prefix), aContext, + getter_AddRefs(lName), namespaceID); + NS_ENSURE_SUCCESS(rv, rv); + + txCoreFunctionCall::eType type; + if (namespaceID == kNameSpaceID_None && + txCoreFunctionCall::getTypeFromAtom(lName, type)) { + // It is a known built-in function. + fnCall = MakeUnique<txCoreFunctionCall>(type); + } + + // check extension functions and xslt + if (!fnCall) { + rv = aContext->resolveFunctionCall(lName, namespaceID, + getter_Transfers(fnCall)); + + if (rv == NS_ERROR_NOT_IMPLEMENTED) { + // this should just happen for unparsed-entity-uri() + NS_ASSERTION(!fnCall, "Now is it implemented or not?"); + rv = parseParameters(0, lexer, aContext); + NS_ENSURE_SUCCESS(rv, rv); + + *aResult = new txLiteralExpr(tok->Value() + u" not implemented."_ns); + + return NS_OK; + } + + NS_ENSURE_SUCCESS(rv, rv); + } + + //-- handle parametes + rv = parseParameters(fnCall.get(), lexer, aContext); + NS_ENSURE_SUCCESS(rv, rv); + + *aResult = fnCall.release(); + return NS_OK; +} + +nsresult txExprParser::createLocationStep(txExprLexer& lexer, + txIParseContext* aContext, + Expr** aExpr) { + *aExpr = nullptr; + + //-- child axis is default + LocationStep::LocationStepType axisIdentifier = LocationStep::CHILD_AXIS; + UniquePtr<txNodeTest> nodeTest; + + //-- get Axis Identifier or AbbreviatedStep, if present + Token* tok = lexer.peek(); + switch (tok->mType) { + case Token::AXIS_IDENTIFIER: { + //-- eat token + lexer.nextToken(); + RefPtr<nsAtom> axis = NS_Atomize(tok->Value()); + if (axis == nsGkAtoms::ancestor) { + axisIdentifier = LocationStep::ANCESTOR_AXIS; + } else if (axis == nsGkAtoms::ancestorOrSelf) { + axisIdentifier = LocationStep::ANCESTOR_OR_SELF_AXIS; + } else if (axis == nsGkAtoms::attribute) { + axisIdentifier = LocationStep::ATTRIBUTE_AXIS; + } else if (axis == nsGkAtoms::child) { + axisIdentifier = LocationStep::CHILD_AXIS; + } else if (axis == nsGkAtoms::descendant) { + axisIdentifier = LocationStep::DESCENDANT_AXIS; + } else if (axis == nsGkAtoms::descendantOrSelf) { + axisIdentifier = LocationStep::DESCENDANT_OR_SELF_AXIS; + } else if (axis == nsGkAtoms::following) { + axisIdentifier = LocationStep::FOLLOWING_AXIS; + } else if (axis == nsGkAtoms::followingSibling) { + axisIdentifier = LocationStep::FOLLOWING_SIBLING_AXIS; + } else if (axis == nsGkAtoms::_namespace) { + axisIdentifier = LocationStep::NAMESPACE_AXIS; + } else if (axis == nsGkAtoms::parent) { + axisIdentifier = LocationStep::PARENT_AXIS; + } else if (axis == nsGkAtoms::preceding) { + axisIdentifier = LocationStep::PRECEDING_AXIS; + } else if (axis == nsGkAtoms::precedingSibling) { + axisIdentifier = LocationStep::PRECEDING_SIBLING_AXIS; + } else if (axis == nsGkAtoms::self) { + axisIdentifier = LocationStep::SELF_AXIS; + } else { + return NS_ERROR_XPATH_INVALID_AXIS; + } + break; + } + case Token::AT_SIGN: + //-- eat token + lexer.nextToken(); + axisIdentifier = LocationStep::ATTRIBUTE_AXIS; + break; + case Token::PARENT_NODE: + //-- eat token + lexer.nextToken(); + axisIdentifier = LocationStep::PARENT_AXIS; + nodeTest = MakeUnique<txNodeTypeTest>(txNodeTypeTest::NODE_TYPE); + break; + case Token::SELF_NODE: + //-- eat token + lexer.nextToken(); + axisIdentifier = LocationStep::SELF_AXIS; + nodeTest = MakeUnique<txNodeTypeTest>(txNodeTypeTest::NODE_TYPE); + break; + default: + break; + } + + //-- get NodeTest unless an AbbreviatedStep was found + nsresult rv = NS_OK; + if (!nodeTest) { + tok = lexer.peek(); + + if (tok->mType == Token::CNAME) { + lexer.nextToken(); + // resolve QName + RefPtr<nsAtom> prefix, lName; + int32_t nspace; + rv = resolveQName(tok->Value(), getter_AddRefs(prefix), aContext, + getter_AddRefs(lName), nspace, true); + NS_ENSURE_SUCCESS(rv, rv); + + nodeTest = MakeUnique<txNameTest>( + prefix, lName, nspace, + axisIdentifier == LocationStep::ATTRIBUTE_AXIS + ? static_cast<uint16_t>(txXPathNodeType::ATTRIBUTE_NODE) + : static_cast<uint16_t>(txXPathNodeType::ELEMENT_NODE)); + } else { + rv = createNodeTypeTest(lexer, getter_Transfers(nodeTest)); + NS_ENSURE_SUCCESS(rv, rv); + } + } + + UniquePtr<LocationStep> lstep( + new LocationStep(nodeTest.get(), axisIdentifier)); + + Unused << nodeTest.release(); + + //-- handle predicates + rv = parsePredicates(lstep.get(), lexer, aContext); + NS_ENSURE_SUCCESS(rv, rv); + + *aExpr = lstep.release(); + return NS_OK; +} + +/** + * This method only handles comment(), text(), processing-instructing() + * and node() + */ +nsresult txExprParser::createNodeTypeTest(txExprLexer& lexer, + txNodeTest** aTest) { + *aTest = 0; + UniquePtr<txNodeTypeTest> nodeTest; + + Token* nodeTok = lexer.peek(); + + switch (nodeTok->mType) { + case Token::COMMENT_AND_PAREN: + lexer.nextToken(); + nodeTest = MakeUnique<txNodeTypeTest>(txNodeTypeTest::COMMENT_TYPE); + break; + case Token::NODE_AND_PAREN: + lexer.nextToken(); + nodeTest = MakeUnique<txNodeTypeTest>(txNodeTypeTest::NODE_TYPE); + break; + case Token::PROC_INST_AND_PAREN: + lexer.nextToken(); + nodeTest = MakeUnique<txNodeTypeTest>(txNodeTypeTest::PI_TYPE); + break; + case Token::TEXT_AND_PAREN: + lexer.nextToken(); + nodeTest = MakeUnique<txNodeTypeTest>(txNodeTypeTest::TEXT_TYPE); + break; + default: + return NS_ERROR_XPATH_NO_NODE_TYPE_TEST; + } + + NS_ENSURE_TRUE(nodeTest, NS_ERROR_OUT_OF_MEMORY); + + if (nodeTok->mType == Token::PROC_INST_AND_PAREN && + lexer.peek()->mType == Token::LITERAL) { + Token* tok = lexer.nextToken(); + nodeTest->setNodeName(tok->Value()); + } + if (lexer.peek()->mType != Token::R_PAREN) { + return NS_ERROR_XPATH_PAREN_EXPECTED; + } + lexer.nextToken(); + + *aTest = nodeTest.release(); + return NS_OK; +} + +/** + * Creates a PathExpr using the given txExprLexer + * @param lexer the txExprLexer for retrieving Tokens + */ +nsresult txExprParser::createPathExpr(txExprLexer& lexer, + txIParseContext* aContext, + Expr** aResult) { + *aResult = nullptr; + + UniquePtr<Expr> expr; + + Token* tok = lexer.peek(); + + // is this a root expression? + if (tok->mType == Token::PARENT_OP) { + if (!isLocationStepToken(lexer.peekAhead())) { + lexer.nextToken(); + *aResult = new RootExpr(); + return NS_OK; + } + } + + // parse first step (possibly a FilterExpr) + nsresult rv = NS_OK; + if (tok->mType != Token::PARENT_OP && tok->mType != Token::ANCESTOR_OP) { + rv = createFilterOrStep(lexer, aContext, getter_Transfers(expr)); + NS_ENSURE_SUCCESS(rv, rv); + + // is this a singlestep path expression? + tok = lexer.peek(); + if (tok->mType != Token::PARENT_OP && tok->mType != Token::ANCESTOR_OP) { + *aResult = expr.release(); + return NS_OK; + } + } else { + expr = MakeUnique<RootExpr>(); + +#ifdef TX_TO_STRING + static_cast<RootExpr*>(expr.get())->setSerialize(false); +#endif + } + + // We have a PathExpr containing several steps + UniquePtr<PathExpr> pathExpr(new PathExpr()); + + rv = pathExpr->addExpr(expr.get(), PathExpr::RELATIVE_OP); + NS_ENSURE_SUCCESS(rv, rv); + + Unused << expr.release(); + + // this is ugly + while (1) { + PathExpr::PathOperator pathOp; + switch (lexer.peek()->mType) { + case Token::ANCESTOR_OP: + pathOp = PathExpr::DESCENDANT_OP; + break; + case Token::PARENT_OP: + pathOp = PathExpr::RELATIVE_OP; + break; + default: + *aResult = pathExpr.release(); + return NS_OK; + } + lexer.nextToken(); + + rv = createLocationStep(lexer, aContext, getter_Transfers(expr)); + NS_ENSURE_SUCCESS(rv, rv); + + rv = pathExpr->addExpr(expr.get(), pathOp); + NS_ENSURE_SUCCESS(rv, rv); + + Unused << expr.release(); + } + MOZ_ASSERT_UNREACHABLE("internal xpath parser error"); + return NS_ERROR_UNEXPECTED; +} + +/** + * Creates a PathExpr using the given txExprLexer + * @param lexer the txExprLexer for retrieving Tokens + */ +nsresult txExprParser::createUnionExpr(txExprLexer& lexer, + txIParseContext* aContext, + Expr** aResult) { + *aResult = nullptr; + + UniquePtr<Expr> expr; + nsresult rv = createPathExpr(lexer, aContext, getter_Transfers(expr)); + NS_ENSURE_SUCCESS(rv, rv); + + if (lexer.peek()->mType != Token::UNION_OP) { + *aResult = expr.release(); + return NS_OK; + } + + UniquePtr<UnionExpr> unionExpr(new UnionExpr()); + + rv = unionExpr->addExpr(expr.get()); + NS_ENSURE_SUCCESS(rv, rv); + + Unused << expr.release(); + + while (lexer.peek()->mType == Token::UNION_OP) { + lexer.nextToken(); //-- eat token + + rv = createPathExpr(lexer, aContext, getter_Transfers(expr)); + NS_ENSURE_SUCCESS(rv, rv); + + rv = unionExpr->addExpr(expr.release()); + NS_ENSURE_SUCCESS(rv, rv); + } + + *aResult = unionExpr.release(); + return NS_OK; +} + +bool txExprParser::isLocationStepToken(Token* aToken) { + // We could put these in consecutive order in ExprLexer.h for speed + return aToken->mType == Token::AXIS_IDENTIFIER || + aToken->mType == Token::AT_SIGN || + aToken->mType == Token::PARENT_NODE || + aToken->mType == Token::SELF_NODE || aToken->mType == Token::CNAME || + aToken->mType == Token::COMMENT_AND_PAREN || + aToken->mType == Token::NODE_AND_PAREN || + aToken->mType == Token::PROC_INST_AND_PAREN || + aToken->mType == Token::TEXT_AND_PAREN; +} + +/** + * Using the given lexer, parses the tokens if they represent a predicate list + * If an error occurs a non-zero String pointer will be returned containing the + * error message. + * @param predicateList, the PredicateList to add predicate expressions to + * @param lexer the txExprLexer to use for parsing tokens + * @return 0 if successful, or a String pointer to the error message + */ +nsresult txExprParser::parsePredicates(PredicateList* aPredicateList, + txExprLexer& lexer, + txIParseContext* aContext) { + UniquePtr<Expr> expr; + nsresult rv = NS_OK; + while (lexer.peek()->mType == Token::L_BRACKET) { + //-- eat Token + lexer.nextToken(); + + rv = createExpr(lexer, aContext, getter_Transfers(expr)); + NS_ENSURE_SUCCESS(rv, rv); + + rv = aPredicateList->add(expr.get()); + NS_ENSURE_SUCCESS(rv, rv); + + Unused << expr.release(); + + if (lexer.peek()->mType != Token::R_BRACKET) { + return NS_ERROR_XPATH_BRACKET_EXPECTED; + } + lexer.nextToken(); + } + return NS_OK; +} + +/** + * Using the given lexer, parses the tokens if they represent a parameter list + * If an error occurs a non-zero String pointer will be returned containing the + * error message. + * @param list, the List to add parameter expressions to + * @param lexer the txExprLexer to use for parsing tokens + * @return NS_OK if successful, or another rv otherwise + */ +nsresult txExprParser::parseParameters(FunctionCall* aFnCall, + txExprLexer& lexer, + txIParseContext* aContext) { + if (lexer.peek()->mType == Token::R_PAREN) { + lexer.nextToken(); + return NS_OK; + } + + UniquePtr<Expr> expr; + nsresult rv = NS_OK; + while (1) { + rv = createExpr(lexer, aContext, getter_Transfers(expr)); + NS_ENSURE_SUCCESS(rv, rv); + + if (aFnCall) { + rv = aFnCall->addParam(expr.release()); + NS_ENSURE_SUCCESS(rv, rv); + } + + switch (lexer.peek()->mType) { + case Token::R_PAREN: + lexer.nextToken(); + return NS_OK; + case Token::COMMA: //-- param separator + lexer.nextToken(); + break; + default: + return NS_ERROR_XPATH_PAREN_EXPECTED; + } + } + + MOZ_ASSERT_UNREACHABLE("internal xpath parser error"); + return NS_ERROR_UNEXPECTED; +} + +short txExprParser::precedence(Token* aToken) { + switch (aToken->mType) { + case Token::OR_OP: + return 1; + case Token::AND_OP: + return 2; + //-- equality + case Token::EQUAL_OP: + case Token::NOT_EQUAL_OP: + return 3; + //-- relational + case Token::LESS_THAN_OP: + case Token::GREATER_THAN_OP: + case Token::LESS_OR_EQUAL_OP: + case Token::GREATER_OR_EQUAL_OP: + return 4; + //-- additive operators + case Token::ADDITION_OP: + case Token::SUBTRACTION_OP: + return 5; + //-- multiplicative + case Token::DIVIDE_OP: + case Token::MULTIPLY_OP: + case Token::MODULUS_OP: + return 6; + default: + break; + } + return 0; +} + +nsresult txExprParser::resolveQName(const nsAString& aQName, nsAtom** aPrefix, + txIParseContext* aContext, + nsAtom** aLocalName, int32_t& aNamespace, + bool aIsNameTest) { + aNamespace = kNameSpaceID_None; + int32_t idx = aQName.FindChar(':'); + if (idx > 0) { + *aPrefix = NS_Atomize(StringHead(aQName, (uint32_t)idx)).take(); + if (!*aPrefix) { + return NS_ERROR_OUT_OF_MEMORY; + } + *aLocalName = NS_Atomize(Substring(aQName, (uint32_t)idx + 1, + aQName.Length() - (idx + 1))) + .take(); + if (!*aLocalName) { + NS_RELEASE(*aPrefix); + return NS_ERROR_OUT_OF_MEMORY; + } + return aContext->resolveNamespacePrefix(*aPrefix, aNamespace); + } + // the lexer dealt with idx == 0 + *aPrefix = 0; + if (aIsNameTest && aContext->caseInsensitiveNameTests()) { + nsAutoString lcname; + nsContentUtils::ASCIIToLower(aQName, lcname); + *aLocalName = NS_Atomize(lcname).take(); + } else { + *aLocalName = NS_Atomize(aQName).take(); + } + if (!*aLocalName) { + return NS_ERROR_OUT_OF_MEMORY; + } + return NS_OK; +} |