parser/html/nsHtml5StringParser.cpp

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this
   3  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   4
   5 #include "nsHtml5StringParser.h"
   6 #include "nsHtml5DependentUTF16Buffer.h"
   7 #include "nsHtml5Tokenizer.h"
   8 #include "nsHtml5TreeBuilder.h"
   9 #include "nsHtml5TreeOpExecutor.h"
  10 #include "nsIContent.h"
  11 #include "mozilla/dom/Document.h"
  12 #include "mozilla/dom/DocumentFragment.h"
  13
  14 using mozilla::dom::Document;
  15
  16 NS_IMPL_ISUPPORTS0(nsHtml5StringParser)
  17
  18 nsHtml5StringParser::nsHtml5StringParser()
  19     : mBuilder(new nsHtml5OplessBuilder()),
  20       mTreeBuilder(new nsHtml5TreeBuilder(mBuilder)),
  21       mTokenizer(new nsHtml5Tokenizer(mTreeBuilder.get(), false)) {
  22   mTokenizer->setInterner(&mAtomTable);
  23   mTokenizer->setKeepBuffer(true);
  24   mTreeBuilder->setKeepBuffer(true);
  25 }
  26
  27 nsHtml5StringParser::~nsHtml5StringParser() { ClearCaches(); }
  28
  29 nsresult nsHtml5StringParser::ParseFragment(
  30     const nsAString& aSourceBuffer, nsIContent* aTargetNode,
  31     nsAtom* aContextLocalName, int32_t aContextNamespace, bool aQuirks,
  32     bool aPreventScriptExecution, bool aAllowDeclarativeShadowRoots) {
  33   NS_ENSURE_TRUE(aSourceBuffer.Length() <= INT32_MAX, NS_ERROR_OUT_OF_MEMORY);
  34
  35   Document* doc = aTargetNode->OwnerDoc();
  36   nsIURI* uri = doc->GetDocumentURI();
  37   NS_ENSURE_TRUE(uri, NS_ERROR_NOT_AVAILABLE);
  38
  39   mTreeBuilder->setFragmentContext(aContextLocalName, aContextNamespace,
  40                                    aTargetNode, aQuirks);
  41
  42 #ifdef DEBUG
  43   if (!aPreventScriptExecution) {
  44     NS_ASSERTION(!aTargetNode->IsInUncomposedDoc(),
  45                  "If script execution isn't prevented, "
  46                  "the target node must not be in doc.");
  47     NS_ASSERTION(
  48         aTargetNode->NodeType() == nsINode::DOCUMENT_FRAGMENT_NODE,
  49         "If script execution isn't prevented, must parse to DOM fragment.");
  50   }
  51 #endif
  52
  53   mTreeBuilder->SetPreventScriptExecution(aPreventScriptExecution);
  54
  55   return Tokenize(aSourceBuffer, doc, true, aAllowDeclarativeShadowRoots);
  56 }
  57
  58 nsresult nsHtml5StringParser::ParseDocument(
  59     const nsAString& aSourceBuffer, Document* aTargetDoc,
  60     bool aScriptingEnabledForNoscriptParsing) {
  61   MOZ_ASSERT(!aTargetDoc->GetFirstChild());
  62
  63   NS_ENSURE_TRUE(aSourceBuffer.Length() <= INT32_MAX, NS_ERROR_OUT_OF_MEMORY);
  64
  65   mTreeBuilder->setFragmentContext(nullptr, kNameSpaceID_None, nullptr, false);
  66
  67   mTreeBuilder->SetPreventScriptExecution(true);
  68
  69   return Tokenize(aSourceBuffer, aTargetDoc,
  70                   aScriptingEnabledForNoscriptParsing,
  71                   aTargetDoc->AllowsDeclarativeShadowRoots());
  72 }
  73
  74 void nsHtml5StringParser::ClearCaches() {
  75   mTokenizer->dropBufferIfLongerThan(0);
  76   mTreeBuilder->dropBufferIfLongerThan(0);
  77   if (mCacheClearer) {
  78     mCacheClearer->Disconnect();
  79     mCacheClearer = nullptr;
  80   }
  81 }
  82
  83 void nsHtml5StringParser::TryCache() {
  84   const int32_t kMaxBuffer = 1024 * 1024;
  85   bool didDrop = mTokenizer->dropBufferIfLongerThan(kMaxBuffer);
  86   didDrop |= mTreeBuilder->dropBufferIfLongerThan(kMaxBuffer);
  87   if (didDrop) {
  88     return;
  89   }
  90
  91   if (!mCacheClearer) {
  92     mCacheClearer = new CacheClearer(this);
  93     nsCOMPtr<nsIRunnable> runnable = mCacheClearer.get();
  94     NS_DispatchToMainThreadQueue(runnable.forget(),
  95                                  mozilla::EventQueuePriority::Idle);
  96   }
  97 }
  98
  99 nsresult nsHtml5StringParser::Tokenize(const nsAString& aSourceBuffer,
 100                                        Document* aDocument,
 101                                        bool aScriptingEnabledForNoscriptParsing,
 102                                        bool aDeclarativeShadowRootsAllowed) {
 103   nsIURI* uri = aDocument->GetDocumentURI();
 104
 105   mBuilder->Init(aDocument, uri, nullptr, nullptr);
 106
 107   mBuilder->SetParser(this);
 108   mBuilder->SetNodeInfoManager(aDocument->NodeInfoManager());
 109
 110   // Mark the parser as *not* broken by passing NS_OK
 111   nsresult rv = mBuilder->MarkAsBroken(NS_OK);
 112
 113   mTreeBuilder->setScriptingEnabled(aScriptingEnabledForNoscriptParsing);
 114   mTreeBuilder->setIsSrcdocDocument(aDocument->IsSrcdocDocument());
 115   mTreeBuilder->setAllowDeclarativeShadowRoots(aDeclarativeShadowRootsAllowed);
 116   mBuilder->Start();
 117   mTokenizer->start();
 118   if (!aSourceBuffer.IsEmpty()) {
 119     bool lastWasCR = false;
 120     nsHtml5DependentUTF16Buffer buffer(aSourceBuffer);
 121     while (buffer.hasMore()) {
 122       buffer.adjust(lastWasCR);
 123       lastWasCR = false;
 124       if (buffer.hasMore()) {
 125         if (!mTokenizer->EnsureBufferSpace(buffer.getLength())) {
 126           rv = mBuilder->MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
 127           break;
 128         }
 129         lastWasCR = mTokenizer->tokenizeBuffer(&buffer);
 130         if (NS_FAILED(rv = mBuilder->IsBroken())) {
 131           break;
 132         }
 133       }
 134     }
 135   }
 136   if (NS_SUCCEEDED(rv)) {
 137     mTokenizer->eof();
 138   }
 139
 140   mTokenizer->end();
 141   mBuilder->Finish();
 142   mAtomTable.Clear();
 143   TryCache();
 144   return rv;
 145 }