dom/xslt/xpath/txExprParser.h

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 /**
   7  * ExprParser
   8  * This class is used to parse XSL Expressions
   9  * @see ExprLexer
  10  **/
  11
  12 #ifndef MITREXSL_EXPRPARSER_H
  13 #define MITREXSL_EXPRPARSER_H
  14
  15 #include "txCore.h"
  16 #include "mozilla/UniquePtr.h"
  17 #include "nsString.h"
  18
  19 class Expr;
  20 class txExprLexer;
  21 class FunctionCall;
  22 class LocationStep;
  23 class nsAtom;
  24 class PredicateList;
  25 class Token;
  26 class txIParseContext;
  27 class txNodeTest;
  28
  29 class txExprParser {
  30  public:
  31   static nsresult createExpr(const nsAString& aExpression,
  32                              txIParseContext* aContext, Expr** aExpr) {
  33     return createExprInternal(aExpression, 0, aContext, aExpr);
  34   }
  35
  36   /**
  37    * Creates an Attribute Value Template using the given value
  38    */
  39   static nsresult createAVT(const nsAString& aAttrValue,
  40                             txIParseContext* aContext, Expr** aResult);
  41
  42  protected:
  43   static nsresult createExprInternal(const nsAString& aExpression,
  44                                      uint32_t aSubStringPos,
  45                                      txIParseContext* aContext, Expr** aExpr);
  46   /**
  47    * Using nsAutoPtr& to optimize passing the ownership to the
  48    * created binary expression objects.
  49    */
  50   static nsresult createBinaryExpr(mozilla::UniquePtr<Expr>& left,
  51                                    mozilla::UniquePtr<Expr>& right, Token* op,
  52                                    Expr** aResult);
  53   static nsresult createExpr(txExprLexer& lexer, txIParseContext* aContext,
  54                              Expr** aResult);
  55   static nsresult createFilterOrStep(txExprLexer& lexer,
  56                                      txIParseContext* aContext, Expr** aResult);
  57   static nsresult createFunctionCall(txExprLexer& lexer,
  58                                      txIParseContext* aContext, Expr** aResult);
  59   static nsresult createLocationStep(txExprLexer& lexer,
  60                                      txIParseContext* aContext, Expr** aResult);
  61   static nsresult createNodeTypeTest(txExprLexer& lexer, txNodeTest** aResult);
  62   static nsresult createPathExpr(txExprLexer& lexer, txIParseContext* aContext,
  63                                  Expr** aResult);
  64   static nsresult createUnionExpr(txExprLexer& lexer, txIParseContext* aContext,
  65                                   Expr** aResult);
  66
  67   static bool isLocationStepToken(Token* aToken);
  68
  69   static short precedence(Token* aToken);
  70
  71   /**
  72    * Resolve a QName, given the mContext parse context.
  73    * Returns prefix and localName as well as namespace ID
  74    */
  75   static nsresult resolveQName(const nsAString& aQName, nsAtom** aPrefix,
  76                                txIParseContext* aContext, nsAtom** aLocalName,
  77                                int32_t& aNamespace, bool aIsNameTest = false);
  78
  79   /**
  80    * Using the given lexer, parses the tokens if they represent a
  81    * predicate list
  82    * If an error occurs a non-zero String pointer will be returned
  83    * containing the error message.
  84    * @param predicateList, the PredicateList to add predicate expressions to
  85    * @param lexer the ExprLexer to use for parsing tokens
  86    * @return 0 if successful, or a String pointer to the error message
  87    */
  88   static nsresult parsePredicates(PredicateList* aPredicateList,
  89                                   txExprLexer& lexer,
  90                                   txIParseContext* aContext);
  91   static nsresult parseParameters(FunctionCall* aFnCall, txExprLexer& lexer,
  92                                   txIParseContext* aContext);
  93 };
  94
  95 #endif