| /**************************************************************************** |
| ** |
| ** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies). |
| ** All rights reserved. |
| ** Contact: Nokia Corporation (qt-info@nokia.com) |
| ** |
| ** This file is part of the QtXmlPatterns module of the Qt Toolkit. |
| ** |
| ** $QT_BEGIN_LICENSE:LGPL$ |
| ** GNU Lesser General Public License Usage |
| ** This file may be used under the terms of the GNU Lesser General Public |
| ** License version 2.1 as published by the Free Software Foundation and |
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| ** file. Please review the following information to ensure the GNU Lesser |
| ** General Public License version 2.1 requirements will be met: |
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| ** |
| ** In addition, as a special exception, Nokia gives you certain additional |
| ** rights. These rights are described in the Nokia Qt LGPL Exception |
| ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. |
| ** |
| ** GNU General Public License Usage |
| ** Alternatively, this file may be used under the terms of the GNU General |
| ** Public License version 3.0 as published by the Free Software Foundation |
| ** and appearing in the file LICENSE.GPL included in the packaging of this |
| ** file. Please review the following information to ensure the GNU General |
| ** Public License version 3.0 requirements will be met: |
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| ** Other Usage |
| ** Alternatively, this file may be used in accordance with the terms and |
| ** conditions contained in a signed written agreement between you and Nokia. |
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| ** $QT_END_LICENSE$ |
| ** |
| ****************************************************************************/ |
| |
| #include "qbuiltintypes_p.h" |
| #include "qcommonsequencetypes_p.h" |
| #include "qcommonvalues_p.h" |
| #include "qebvextractor_p.h" |
| #include "qitem_p.h" |
| #include "qliteral_p.h" |
| #include "qoptimizationpasses_p.h" |
| #include "quntypedatomicconverter_p.h" |
| #include "qvaluecomparison_p.h" |
| |
| #include "qgeneralcomparison_p.h" |
| |
| QT_BEGIN_NAMESPACE |
| |
| using namespace QPatternist; |
| |
| GeneralComparison::GeneralComparison(const Expression::Ptr &op1, |
| const AtomicComparator::Operator op, |
| const Expression::Ptr &op2, |
| const bool isBackwardsCompat) : PairContainer(op1, op2) |
| , m_operator(op) |
| , m_isBackwardsCompat(isBackwardsCompat) |
| { |
| } |
| |
| bool GeneralComparison::generalCompare(const Item &op1, |
| const Item &op2, |
| const DynamicContext::Ptr &context) const |
| { |
| Q_ASSERT(op1); |
| Q_ASSERT(op2); |
| |
| if(comparator()) |
| return compare(op1, op2, comparator(), m_operator); |
| |
| Expression::Ptr a1(new Literal(op1)); |
| Expression::Ptr a2(new Literal(op2)); |
| |
| const AtomicComparator::Ptr comp(fetchGeneralComparator(a1, a2, context)); |
| /* The fetchGeneralComparator call may rewrite a1 and/or a2. */ |
| Q_ASSERT(a1); |
| Q_ASSERT(a2); |
| Q_ASSERT(comp); |
| |
| return compare(a1->evaluateSingleton(context), |
| a2->evaluateSingleton(context), |
| comp, |
| m_operator); |
| } |
| |
| bool GeneralComparison::evaluateEBV(const DynamicContext::Ptr &context) const |
| { |
| const Item::Iterator::Ptr it1(m_operand1->evaluateSequence(context)); |
| Item item1(it1->next()); |
| |
| if(!item1) |
| return false; |
| |
| const Item::Iterator::Ptr it2(m_operand2->evaluateSequence(context)); |
| Item::List cache; |
| Item item2; |
| |
| while(true) |
| { |
| item2 = it2->next(); |
| if(!item2) |
| break; |
| |
| if(generalCompare(item1, item2, context)) |
| return true; |
| |
| cache.append(item2); |
| } |
| |
| while(true) |
| { |
| item1 = it1->next(); |
| |
| if(!item1) |
| return false; |
| |
| const Item::List::const_iterator end(cache.constEnd()); |
| Item::List::const_iterator it(cache.constBegin()); |
| |
| for(; it != end; ++it) |
| if(generalCompare(item1, *it, context)) |
| return true; |
| } |
| |
| Q_ASSERT(false); |
| return false; |
| } |
| |
| Expression::Ptr GeneralComparison::compress(const StaticContext::Ptr &context) |
| { |
| const Expression::Ptr me(PairContainer::compress(context)); |
| |
| if(me != this) |
| return me; |
| |
| if(ValueComparison::isCaseInsensitiveCompare(m_operand1, m_operand2)) |
| useCaseInsensitiveComparator(); |
| |
| return me; |
| } |
| |
| Expression::Ptr GeneralComparison::typeCheck(const StaticContext::Ptr &context, |
| const SequenceType::Ptr &reqType) |
| { |
| |
| const Expression::Ptr me(PairContainer::typeCheck(context, reqType)); |
| |
| const ItemType::Ptr t1(m_operand1->staticType()->itemType()); |
| const ItemType::Ptr t2(m_operand2->staticType()->itemType()); |
| |
| if(*CommonSequenceTypes::Empty == *t1 || |
| *CommonSequenceTypes::Empty == *t2) |
| { |
| return wrapLiteral(CommonValues::BooleanFalse, context, this); |
| } |
| |
| if(*BuiltinTypes::xsAnyAtomicType == *t1 || |
| *BuiltinTypes::xsAnyAtomicType == *t2) |
| return me; |
| |
| prepareComparison(fetchGeneralComparator(m_operand1, m_operand2, context)); |
| |
| if(!m_operand1->staticType()->cardinality().allowsMany() && |
| !m_operand2->staticType()->cardinality().allowsMany()) |
| { |
| /* Rewrite to a ValueComparison whose operands uses typing rules |
| * as for an general comparison(that's what's done above). */ |
| return rewrite(Expression::Ptr(new ValueComparison(m_operand1, |
| m_operator, |
| m_operand2))->typeCheck(context, reqType), |
| context); |
| } |
| else |
| return me; |
| } |
| |
| void GeneralComparison::updateType(ItemType::Ptr &type, |
| const Expression::Ptr &source) |
| { |
| type = source->staticType()->itemType(); |
| } |
| |
| AtomicComparator::Ptr GeneralComparison::fetchGeneralComparator(Expression::Ptr &op1, |
| Expression::Ptr &op2, |
| const ReportContext::Ptr &context) const |
| { |
| ItemType::Ptr t1(op1->staticType()->itemType()); |
| ItemType::Ptr t2(op2->staticType()->itemType()); |
| |
| /* a. "If one of the atomic values is an instance of xs:untypedAtomic and |
| * the other is an instance of a numeric type, then the xs:untypedAtomic |
| * value is cast to the type xs:double." */ |
| if(BuiltinTypes::numeric->xdtTypeMatches(t1) && |
| BuiltinTypes::xsUntypedAtomic->xdtTypeMatches(t2)) |
| { |
| op2 = Expression::Ptr(new UntypedAtomicConverter(op2, BuiltinTypes::xsDouble)); |
| |
| /* The types might have changed, reload. */ |
| updateType(t2, op2); |
| } |
| else if(BuiltinTypes::numeric->xdtTypeMatches(t2) && |
| BuiltinTypes::xsUntypedAtomic->xdtTypeMatches(t1)) |
| { |
| op1 = Expression::Ptr(new UntypedAtomicConverter(op1, BuiltinTypes::xsDouble)); |
| |
| /* The types might have changed, reload. */ |
| updateType(t1, op1); |
| } |
| /* "If XPath 1.0 compatibility mode is true, a general comparison is |
| * evaluated by applying the following rules, in order: |
| * 1. If either operand is a single atomic value that is an instance of |
| * xs:boolean, then the other operand is converted to xs:boolean by taking |
| * its effective boolean value." |
| * |
| * Notably, it's not conversion to boolean, it is EBV extraction. |
| */ |
| else if(m_isBackwardsCompat && BuiltinTypes::xsBoolean->xdtTypeMatches(t1)) |
| { |
| op2 = Expression::Ptr(new EBVExtractor(op2)); |
| updateType(t2, op2); |
| } |
| else if(m_isBackwardsCompat && BuiltinTypes::xsBoolean->xdtTypeMatches(t2)) |
| { |
| op1 = Expression::Ptr(new EBVExtractor(op1)); |
| updateType(t1, op1); |
| } |
| /* b. "If one of the atomic values is an instance of xs:untypedAtomic and |
| * the other is an instance of xs:untypedAtomic or xs:string, then the |
| * xs:untypedAtomic value (or values) is (are) cast to the type xs:string." |
| * |
| * c. "If one of the atomic values is an instance of xs:untypedAtomic and the |
| * other is not an instance of xs:string, xs:untypedAtomic, or any numeric |
| * type, then the xs:untypedAtomic value is cast to the dynamic type of the |
| * other value." */ |
| else if(BuiltinTypes::xsUntypedAtomic->xdtTypeMatches(t1) && |
| !BuiltinTypes::xsString->xdtTypeMatches(t2) && |
| !BuiltinTypes::xsUntypedAtomic->xdtTypeMatches(t2) && |
| !BuiltinTypes::xsAnyURI->xdtTypeMatches(t2)) |
| { |
| op1 = Expression::Ptr(new UntypedAtomicConverter(op1, t2)); |
| updateType(t1, op1); |
| } |
| else if(BuiltinTypes::xsUntypedAtomic->xdtTypeMatches(t2) && |
| !BuiltinTypes::xsString->xdtTypeMatches(t1) && |
| !BuiltinTypes::xsUntypedAtomic->xdtTypeMatches(t1) && |
| !BuiltinTypes::xsAnyURI->xdtTypeMatches(t1)) |
| { |
| op2 = Expression::Ptr(new UntypedAtomicConverter(op2, t1)); |
| updateType(t2, op2); |
| } |
| |
| /* d. "After performing the conversions described above, the atomic |
| * values are compared using one of the value comparison operators |
| * eq, ne, lt, le, gt, or ge, depending on whether the general comparison |
| * operator was =, !=, <, <=, >, or >=. The values have the required |
| * magnitude relationship if and only if the result of this value comparison |
| * is true." */ |
| |
| return fetchComparator(t1, t2, context); |
| } |
| |
| OptimizationPass::List GeneralComparison::optimizationPasses() const |
| { |
| Q_ASSERT(!OptimizationPasses::comparisonPasses.isEmpty()); |
| return OptimizationPasses::comparisonPasses; |
| } |
| |
| SequenceType::List GeneralComparison::expectedOperandTypes() const |
| { |
| SequenceType::List result; |
| result.append(CommonSequenceTypes::ZeroOrMoreAtomicTypes); |
| result.append(CommonSequenceTypes::ZeroOrMoreAtomicTypes); |
| return result; |
| } |
| |
| SequenceType::Ptr GeneralComparison::staticType() const |
| { |
| return CommonSequenceTypes::ExactlyOneBoolean; |
| } |
| |
| ExpressionVisitorResult::Ptr GeneralComparison::accept(const ExpressionVisitor::Ptr &visitor) const |
| { |
| return visitor->visit(this); |
| } |
| |
| Expression::ID GeneralComparison::id() const |
| { |
| return IDGeneralComparison; |
| } |
| |
| QT_END_NAMESPACE |