dom/xslt/xpath/XPathEvaluator.cpp

   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 #include "mozilla/dom/XPathEvaluator.h"
   7
   8 #include <utility>
   9
  10 #include "XPathResult.h"
  11 #include "mozilla/UniquePtrExtensions.h"
  12 #include "mozilla/dom/BindingUtils.h"
  13 #include "mozilla/dom/Document.h"
  14 #include "mozilla/dom/XPathEvaluatorBinding.h"
  15 #include "mozilla/dom/XPathExpression.h"
  16 #include "mozilla/dom/XPathNSResolverBinding.h"
  17 #include "nsAtom.h"
  18 #include "nsCOMPtr.h"
  19 #include "nsContentUtils.h"
  20 #include "nsDOMString.h"
  21 #include "nsError.h"
  22 #include "nsNameSpaceManager.h"
  23 #include "txExpr.h"
  24 #include "txExprParser.h"
  25 #include "txIXPathContext.h"
  26 #include "txURIUtils.h"
  27
  28 namespace mozilla::dom {
  29
  30 // txIParseContext implementation
  31 class XPathEvaluatorParseContext : public txIParseContext {
  32  public:
  33   XPathEvaluatorParseContext(XPathNSResolver* aResolver, bool aIsCaseSensitive)
  34       : mResolver(aResolver),
  35         mResolverNode(nullptr),
  36         mLastError(NS_OK),
  37         mIsCaseSensitive(aIsCaseSensitive) {}
  38   XPathEvaluatorParseContext(nsINode* aResolver, bool aIsCaseSensitive)
  39       : mResolver(nullptr),
  40         mResolverNode(aResolver),
  41         mLastError(NS_OK),
  42         mIsCaseSensitive(aIsCaseSensitive) {}
  43
  44   nsresult getError() { return mLastError; }
  45
  46   nsresult resolveNamespacePrefix(nsAtom* aPrefix, int32_t& aID) override;
  47   nsresult resolveFunctionCall(nsAtom* aName, int32_t aID,
  48                                FunctionCall** aFunction) override;
  49   bool caseInsensitiveNameTests() override;
  50   void SetErrorOffset(uint32_t aOffset) override;
  51
  52  private:
  53   XPathNSResolver* mResolver;
  54   nsINode* mResolverNode;
  55   nsresult mLastError;
  56   bool mIsCaseSensitive;
  57 };
  58
  59 XPathEvaluator::XPathEvaluator(Document* aDocument) : mDocument(aDocument) {}
  60
  61 XPathEvaluator::~XPathEvaluator() = default;
  62
  63 UniquePtr<XPathExpression> XPathEvaluator::CreateExpression(
  64     const nsAString& aExpression, XPathNSResolver* aResolver,
  65     ErrorResult& aRv) {
  66   nsCOMPtr<Document> doc(mDocument);
  67   XPathEvaluatorParseContext pContext(aResolver,
  68                                       !(doc && doc->IsHTMLDocument()));
  69   return CreateExpression(aExpression, &pContext, doc, aRv);
  70 }
  71
  72 UniquePtr<XPathExpression> XPathEvaluator::CreateExpression(
  73     const nsAString& aExpression, nsINode* aResolver, ErrorResult& aRv) {
  74   nsCOMPtr<Document> doc(mDocument);
  75   XPathEvaluatorParseContext pContext(aResolver,
  76                                       !(doc && doc->IsHTMLDocument()));
  77   return CreateExpression(aExpression, &pContext, doc, aRv);
  78 }
  79
  80 UniquePtr<XPathExpression> XPathEvaluator::CreateExpression(
  81     const nsAString& aExpression, txIParseContext* aContext,
  82     Document* aDocument, ErrorResult& aRv) {
  83   if (!mRecycler) {
  84     mRecycler = new txResultRecycler;
  85   }
  86
  87   UniquePtr<Expr> expression;
  88   aRv = txExprParser::createExpr(PromiseFlatString(aExpression), aContext,
  89                                  getter_Transfers(expression));
  90   if (aRv.Failed()) {
  91     if (!aRv.ErrorCodeIs(NS_ERROR_DOM_NAMESPACE_ERR)) {
  92       aRv.SuppressException();
  93       aRv.ThrowSyntaxError("The expression is not a legal expression");
  94     }
  95
  96     return nullptr;
  97   }
  98
  99   return MakeUnique<XPathExpression>(std::move(expression), mRecycler,
 100                                      aDocument);
 101 }
 102
 103 bool XPathEvaluator::WrapObject(JSContext* aCx,
 104                                 JS::Handle<JSObject*> aGivenProto,
 105                                 JS::MutableHandle<JSObject*> aReflector) {
 106   return dom::XPathEvaluator_Binding::Wrap(aCx, this, aGivenProto, aReflector);
 107 }
 108
 109 /* static */
 110 UniquePtr<XPathEvaluator> XPathEvaluator::Constructor(
 111     const GlobalObject& aGlobal) {
 112   return MakeUnique<XPathEvaluator>(nullptr);
 113 }
 114
 115 already_AddRefed<XPathResult> XPathEvaluator::Evaluate(
 116     JSContext* aCx, const nsAString& aExpression, nsINode& aContextNode,
 117     XPathNSResolver* aResolver, uint16_t aType, JS::Handle<JSObject*> aResult,
 118     ErrorResult& rv) {
 119   UniquePtr<XPathExpression> expression(
 120       CreateExpression(aExpression, aResolver, rv));
 121   if (rv.Failed()) {
 122     return nullptr;
 123   }
 124   return expression->Evaluate(aCx, aContextNode, aType, aResult, rv);
 125 }
 126
 127 /*
 128  * Implementation of txIParseContext private to XPathEvaluator, based on a
 129  * XPathNSResolver
 130  */
 131
 132 nsresult XPathEvaluatorParseContext::resolveNamespacePrefix(nsAtom* aPrefix,
 133                                                             int32_t& aID) {
 134   aID = kNameSpaceID_Unknown;
 135
 136   if (!mResolver && !mResolverNode) {
 137     return NS_ERROR_DOM_NAMESPACE_ERR;
 138   }
 139
 140   nsAutoString prefix;
 141   if (aPrefix) {
 142     aPrefix->ToString(prefix);
 143   }
 144
 145   nsAutoString ns;
 146   if (mResolver) {
 147     ErrorResult rv;
 148     mResolver->LookupNamespaceURI(prefix, ns, rv);
 149     if (rv.Failed()) {
 150       return rv.StealNSResult();
 151     }
 152   } else {
 153     if (aPrefix == nsGkAtoms::xml) {
 154       ns.AssignLiteral("http://www.w3.org/XML/1998/namespace");
 155     } else {
 156       mResolverNode->LookupNamespaceURI(prefix, ns);
 157     }
 158   }
 159
 160   if (DOMStringIsNull(ns)) {
 161     return NS_ERROR_DOM_NAMESPACE_ERR;
 162   }
 163
 164   if (ns.IsEmpty()) {
 165     aID = kNameSpaceID_None;
 166
 167     return NS_OK;
 168   }
 169
 170   // get the namespaceID for the URI
 171   return nsNameSpaceManager::GetInstance()->RegisterNameSpace(ns, aID);
 172 }
 173
 174 nsresult XPathEvaluatorParseContext::resolveFunctionCall(nsAtom* aName,
 175                                                          int32_t aID,
 176                                                          FunctionCall** aFn) {
 177   return NS_ERROR_XPATH_UNKNOWN_FUNCTION;
 178 }
 179
 180 bool XPathEvaluatorParseContext::caseInsensitiveNameTests() {
 181   return !mIsCaseSensitive;
 182 }
 183
 184 void XPathEvaluatorParseContext::SetErrorOffset(uint32_t aOffset) {}
 185
 186 }  // namespace mozilla::dom