Source/core/html/track/vtt/VTTTokenizer.h

/*
 * Copyright (C) 2011 Google Inc.  All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 *
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 * in the documentation and/or other materials provided with the
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#ifndef VTTTokenizer_h
#define VTTTokenizer_h

#include "core/html/parser/InputStreamPreprocessor.h"
#include "core/html/track/vtt/VTTToken.h"
#include "wtf/PassOwnPtr.h"

namespace WebCore {

class VTTTokenizerState {
public:
    enum State {
        DataState,
        EscapeState,
        TagState,
        StartTagState,
        StartTagClassState,
        StartTagAnnotationState,
        EndTagState,
        TimestampTagState,
    };
};

class VTTTokenizer {
    WTF_MAKE_NONCOPYABLE(VTTTokenizer);
public:
    explicit VTTTokenizer(const String& input);

    typedef VTTTokenizerState State;

    void reset();

    bool nextToken(VTTToken&);

    inline bool haveBufferedCharacterToken() { return false; }

    inline bool advanceAndEmitToken(SegmentedString& source, const VTTToken& token)
    {
        source.advanceAndUpdateLineNumber();
        return emitToken(token);
    }

    inline bool emitToken(const VTTToken& token)
    {
        *m_token = token;
        return true;
    }

    bool shouldSkipNullCharacters() const { return true; }

private:
    // m_token is owned by the caller. If nextToken is not on the stack,
    // this member might be pointing to unallocated memory.
    VTTToken* m_token;

    // This member does not really need to be an instance member - it's only used in nextToken.
    // The reason it's stored here is because of the use of the ADVANCE_TO state helpers.
    VTTTokenizerState::State m_state;

    SegmentedString m_input;

    // ://www.whatwg.org/specs/web-apps/current-work/#preprocessing-the-input-stream
    InputStreamPreprocessor<VTTTokenizer> m_inputStreamPreprocessor;
};

}

#endif