dom/xslt/xpath/txIXPathContext.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 #ifndef __TX_I_XPATH_CONTEXT
   7 #define __TX_I_XPATH_CONTEXT
   8
   9 #include "nscore.h"
  10 #include "nsISupportsImpl.h"
  11 #include "nsStringFwd.h"
  12
  13 class FunctionCall;
  14 class nsAtom;
  15 class txAExprResult;
  16 class txResultRecycler;
  17 class txXPathNode;
  18
  19 /*
  20  * txIParseContext
  21  *
  22  * This interface describes the context needed to create
  23  * XPath Expressions and XSLT Patters.
  24  * (not completely though. key() requires the ProcessorState, which is
  25  * not part of this interface.)
  26  */
  27
  28 class txIParseContext {
  29  public:
  30   virtual ~txIParseContext() = default;
  31
  32   /*
  33    * Return a namespaceID for a given prefix.
  34    */
  35   virtual nsresult resolveNamespacePrefix(nsAtom* aPrefix, int32_t& aID) = 0;
  36
  37   /*
  38    * Create a FunctionCall, needed for extension function calls and
  39    * XSLT. XPath function calls are resolved by the Parser.
  40    */
  41   virtual nsresult resolveFunctionCall(nsAtom* aName, int32_t aID,
  42                                        FunctionCall** aFunction) = 0;
  43
  44   /**
  45    * Should nametests parsed in this context be case-sensitive
  46    */
  47   virtual bool caseInsensitiveNameTests() = 0;
  48
  49   /*
  50    * Callback to be used by the Parser if errors are detected.
  51    */
  52   virtual void SetErrorOffset(uint32_t aOffset) = 0;
  53
  54   enum Allowed { KEY_FUNCTION = 1 << 0 };
  55   virtual bool allowed(Allowed aAllowed) { return true; }
  56 };
  57
  58 /*
  59  * txIMatchContext
  60  *
  61  * Interface used for matching XSLT Patters.
  62  * This is the part of txIEvalContext (see below), that is independent
  63  * of the context node when evaluating a XPath expression, too.
  64  * When evaluating a XPath expression, |txIMatchContext|s are used
  65  * to transport the information from Step to Step.
  66  */
  67 class txIMatchContext {
  68  public:
  69   virtual ~txIMatchContext() = default;
  70
  71   /*
  72    * Return the ExprResult associated with the variable with the
  73    * given namespace and local name.
  74    */
  75   virtual nsresult getVariable(int32_t aNamespace, nsAtom* aLName,
  76                                txAExprResult*& aResult) = 0;
  77
  78   /*
  79    * Is whitespace stripping allowed for the given node?
  80    * See http://www.w3.org/TR/xslt#strip
  81    */
  82   virtual nsresult isStripSpaceAllowed(const txXPathNode& aNode,
  83                                        bool& aAllowed) = 0;
  84
  85   /**
  86    * Returns a pointer to the private context
  87    */
  88   virtual void* getPrivateContext() = 0;
  89
  90   virtual txResultRecycler* recycler() = 0;
  91
  92   /*
  93    * Callback to be used by the expression/pattern if errors are detected.
  94    */
  95   virtual void receiveError(const nsAString& aMsg, nsresult aRes) = 0;
  96 };
  97
  98 #define TX_DECL_MATCH_CONTEXT                                            \
  99   nsresult getVariable(int32_t aNamespace, nsAtom* aLName,               \
 100                        txAExprResult*& aResult) override;                \
 101   nsresult isStripSpaceAllowed(const txXPathNode& aNode, bool& aAllowed) \
 102       override;                                                          \
 103   void* getPrivateContext() override;                                    \
 104   txResultRecycler* recycler() override;                                 \
 105   void receiveError(const nsAString& aMsg, nsresult aRes) override
 106
 107 class txIEvalContext : public txIMatchContext {
 108  public:
 109   /*
 110    * Get the context node.
 111    */
 112   virtual const txXPathNode& getContextNode() = 0;
 113
 114   /*
 115    * Get the size of the context node set.
 116    */
 117   virtual uint32_t size() = 0;
 118
 119   /*
 120    * Get the position of the context node in the context node set,
 121    * starting with 1.
 122    */
 123   virtual uint32_t position() = 0;
 124 };
 125
 126 #define TX_DECL_EVAL_CONTEXT                    \
 127   TX_DECL_MATCH_CONTEXT;                        \
 128   const txXPathNode& getContextNode() override; \
 129   uint32_t size() override;                     \
 130   uint32_t position() override
 131
 132 #endif  // __TX_I_XPATH_CONTEXT