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 <wtf/Forward.h>
28#include <wtf/RefCounted.h>
29
30namespace WebCore {
31
32class Document;
33class DocumentWriter;
34class SegmentedString;
35class ScriptableDocumentParser;
36
37class DocumentParser : public RefCounted<DocumentParser> {
38public:
39    virtual ~DocumentParser();
40
41    virtual ScriptableDocumentParser* asScriptableDocumentParser() { return 0; }
42
43    // http://www.whatwg.org/specs/web-apps/current-work/#insertion-point
44    virtual bool hasInsertionPoint() { return true; }
45
46    // insert is used by document.write.
47    virtual void insert(const SegmentedString&) = 0;
48
49    // appendBytes and flush are used by DocumentWriter (the loader).
50    virtual void appendBytes(DocumentWriter*, const char* bytes, size_t length) = 0;
51    virtual void flush(DocumentWriter*) = 0;
52
53    virtual void pinToMainThread() { }
54
55    // FIXME: append() should be private, but DocumentWriter::replaceDocument uses it for now.
56    // FIXME: This really should take a PassOwnPtr to signify that it expects to take
57    // ownership of the buffer. The parser expects the PassRefPtr to hold the only ref of the StringImpl.
58    virtual void append(PassRefPtr<StringImpl>) = 0;
59
60    virtual void finish() = 0;
61
62    // FIXME: processingData() is only used by DocumentLoader::isLoadingInAPISense
63    // and is very unclear as to what it actually means.  The LegacyHTMLDocumentParser
64    // used to implement it.
65    virtual bool processingData() const { return false; }
66
67    // document() will return 0 after detach() is called.
68    Document* document() const { ASSERT(m_document); return m_document; }
69
70    bool isParsing() const { return m_state == ParsingState; }
71    bool isStopping() const { return m_state == StoppingState; }
72    bool isStopped() const { return m_state >= StoppedState; }
73    bool isDetached() const { return m_state == DetachedState; }
74
75    // FIXME: Is this necessary? Does XMLDocumentParserLibxml2 really need to set this?
76    virtual void startParsing();
77
78    // prepareToStop() is used when the EOF token is encountered and parsing is to be
79    // stopped normally.
80    virtual void prepareToStopParsing();
81
82    // stopParsing() is used when a load is canceled/stopped.
83    // stopParsing() is currently different from detach(), but shouldn't be.
84    // It should NOT be ok to call any methods on DocumentParser after either
85    // detach() or stopParsing() but right now only detach() will ASSERT.
86    virtual void stopParsing();
87
88    // Document is expected to detach the parser before releasing its ref.
89    // After detach, m_document is cleared.  The parser will unwind its
90    // callstacks, but not produce any more nodes.
91    // It is impossible for the parser to touch the rest of WebCore after
92    // detach is called.
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
102protected:
103    explicit DocumentParser(Document*);
104
105private:
106    enum ParserState {
107        ParsingState,
108        StoppingState,
109        StoppedState,
110        DetachedState
111    };
112    ParserState m_state;
113    bool m_documentWasLoadedAsPartOfNavigation;
114
115    // Every DocumentParser needs a pointer back to the document.
116    // m_document will be 0 after the parser is stopped.
117    Document* m_document;
118};
119
120} // namespace WebCore
121
122#endif // DocumentParser_h
123