third_party/WebKit/Source/core/dom/DocumentParser.h

   1 /*
   2  * Copyright (C) 2000 Peter Kelly (pmk@post.com)
   3  * Copyright (C) 2005, 2006 Apple Computer, Inc.
   4  * Copyright (C) 2007 Samuel Weinig (sam@webkit.org)
   5  * Copyright (C) 2010 Google, Inc.
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Library General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Library General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Library General Public License
  18  * along with this library; see the file COPYING.LIB.  If not, write to
  19  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  20  * Boston, MA 02110-1301, USA.
  21  *
  22  */
  23
  24 #ifndef DocumentParser_h
  25 #define DocumentParser_h
  26
  27 #include "platform/heap/Handle.h"
  28 #include "wtf/Forward.h"
  29 #include "wtf/RefCounted.h"
  30
  31 namespace blink {
  32
  33 class Document;
  34 class DocumentParserClient;
  35 class SegmentedString;
  36 class ScriptableDocumentParser;
  37 class TextResourceDecoder;
  38
  39 class DocumentParser : public RefCountedWillBeGarbageCollectedFinalized<DocumentParser> {
  40 public:
  41     virtual ~DocumentParser();
  42     DECLARE_VIRTUAL_TRACE();
  43
  44     virtual ScriptableDocumentParser* asScriptableDocumentParser() { return 0; }
  45
  46     // http://www.whatwg.org/specs/web-apps/current-work/#insertion-point
  47     virtual bool hasInsertionPoint() { return true; }
  48
  49     // insert is used by document.write.
  50     virtual void insert(const SegmentedString&) = 0;
  51
  52     // The below functions are used by DocumentWriter (the loader).
  53     virtual void appendBytes(const char* bytes, size_t length) = 0;
  54     virtual bool needsDecoder() const { return false; }
  55     virtual void setDecoder(PassOwnPtr<TextResourceDecoder>);
  56     virtual TextResourceDecoder* decoder();
  57     virtual void setHasAppendedData() { }
  58
  59     // FIXME: append() should be private, but DocumentLoader and DOMPatchSupport uses it for now.
  60     virtual void append(const String&) = 0;
  61
  62     virtual void finish() = 0;
  63
  64     // FIXME: processingData() is only used by DocumentLoader::isLoadingInAPISense
  65     // and is very unclear as to what it actually means.  The LegacyHTMLDocumentParser
  66     // used to implement it.
  67     virtual bool processingData() const { return false; }
  68
  69     // document() will return 0 after detach() is called.
  70     Document* document() const { ASSERT(m_document); return m_document; }
  71
  72     bool isParsing() const { return m_state == ParsingState; }
  73     bool isStopping() const { return m_state == StoppingState; }
  74     bool isStopped() const { return m_state >= StoppedState; }
  75     bool isDetached() const { return m_state == DetachedState; }
  76
  77     // prepareToStop() is used when the EOF token is encountered and parsing is to be
  78     // stopped normally.
  79     virtual void prepareToStopParsing();
  80
  81     // stopParsing() is used when a load is canceled/stopped.
  82     // stopParsing() is currently different from detach(), but shouldn't be.
  83     // It should NOT be ok to call any methods on DocumentParser after either
  84     // detach() or stopParsing() but right now only detach() will ASSERT.
  85     virtual void stopParsing();
  86
  87     // Document is expected to detach the parser before releasing its ref.
  88     // After detach, m_document is cleared.  The parser will unwind its
  89     // callstacks, but not produce any more nodes.
  90     // It is impossible for the parser to touch the rest of WebCore after
  91     // detach is called.
  92     // Oilpan: We don't need to call detach when a Document is destructed.
  93     virtual void detach();
  94
  95     void setDocumentWasLoadedAsPartOfNavigation() { m_documentWasLoadedAsPartOfNavigation = true; }
  96     bool documentWasLoadedAsPartOfNavigation() const { return m_documentWasLoadedAsPartOfNavigation; }
  97
  98     // FIXME: The names are not very accurate :(
  99     virtual void suspendScheduledTasks();
 100     virtual void resumeScheduledTasks();
 101
 102     void addClient(DocumentParserClient*);
 103     void removeClient(DocumentParserClient*);
 104
 105 protected:
 106     explicit DocumentParser(Document*);
 107
 108     virtual void flush() = 0;
 109
 110 private:
 111     enum ParserState {
 112         ParsingState,
 113         StoppingState,
 114         StoppedState,
 115         DetachedState
 116     };
 117     ParserState m_state;
 118     bool m_documentWasLoadedAsPartOfNavigation;
 119
 120     // Every DocumentParser needs a pointer back to the document.
 121     // m_document will be 0 after the parser is stopped.
 122     RawPtrWillBeMember<Document> m_document;
 123
 124     WillBeHeapHashSet<RawPtrWillBeWeakMember<DocumentParserClient>> m_clients;
 125 };
 126
 127 } // namespace blink
 128
 129 #endif // DocumentParser_h