document.h

linux下开源浏览器WebKit的源码,市面上的很多商用浏览器都是移植自WebKit

/*
 * Copyright (C) 1999 Lars Knoll ([e-mail])
 *           (C) 1999 Antti Koivisto ([e-mail])
 *           (C) 2001 Dirk Mueller ([e-mail])
 *           (C) 2006 Alexey Proskuryakov ([e-mail])
 * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
 * Copyright (C) 2008 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 *
 */

#ifndef Document_h
#define Document_h

#include "Attr.h"
#include "Color.h"
#include "DocumentMarker.h"
#include "HTMLCollection.h"
#include "HTMLFormElement.h"
#include "ScriptExecutionContext.h"
#include "StringHash.h"
#include "Timer.h"
#include <wtf/HashCountedSet.h>
#include <wtf/ListHashSet.h>

// FIXME: We should move Mac off of the old Frame-based user stylesheet loading
// code and onto the new code in Page. We can't do that until the code in Page
// supports non-file: URLs, however.
#if PLATFORM(MAC) || PLATFORM(QT)
#define FRAME_LOADS_USER_STYLESHEET 1
#else
#define FRAME_LOADS_USER_STYLESHEET 0
#endif

namespace WebCore {

    class AXObjectCache;
    class Attr;
    class Attribute;
    class CDATASection;
    class CachedCSSStyleSheet;
    class CanvasRenderingContext2D;
    class CharacterData;
    class CSSStyleDeclaration;
    class CSSStyleSelector;
    class CSSStyleSheet;
    class Comment;
    class Database;
    class DOMImplementation;
    class DOMSelection;
    class DOMWindow;
    class DatabaseThread;
    class DocLoader;
    class DocumentFragment;
    class DocumentType;
    class EditingText;
    class Element;
    class EntityReference;
    class Event;
    class EventListener;
    class FormControlElementWithState;
    class Frame;
    class FrameView;
    class HitTestRequest;
    class HTMLCanvasElement;
    class HTMLDocument;
    class HTMLElement;
    class HTMLFormElement;
    class HTMLHeadElement;
    class HTMLInputElement;
    class HTMLMapElement;
    class ImageLoader;
    class IntPoint;
    class JSNode;
    class MouseEventWithHitTestResults;
    class NodeFilter;
    class NodeIterator;
    class Page;
    class PlatformMouseEvent;
    class ProcessingInstruction;
    class Range;
    class RegisteredEventListener;
    class RenderArena;
    class RenderView;
    class SecurityOrigin;
    class SegmentedString;
    class Settings;
    class StyleSheet;
    class StyleSheetList;
    class Text;
    class TextResourceDecoder;
    class Tokenizer;
    class TreeWalker;
    class XMLHttpRequest;

#if ENABLE(SVG)
    class SVGDocumentExtensions;
#endif
    
#if ENABLE(XBL)
    class XBLBindingManager;
#endif

#if ENABLE(XPATH)
    class XPathEvaluator;
    class XPathExpression;
    class XPathNSResolver;
    class XPathResult;
#endif

#if ENABLE(DASHBOARD_SUPPORT)
    struct DashboardRegionValue;
#endif

    typedef int ExceptionCode;

class FormElementKey {
public:
    FormElementKey(AtomicStringImpl* = 0, AtomicStringImpl* = 0);
    ~FormElementKey();
    FormElementKey(const FormElementKey&);
    FormElementKey& operator=(const FormElementKey&);

    AtomicStringImpl* name() const { return m_name; }
    AtomicStringImpl* type() const { return m_type; }

    // Hash table deleted values, which are only constructed and never copied or destroyed.
    FormElementKey(WTF::HashTableDeletedValueType) : m_name(hashTableDeletedValue()) { }
    bool isHashTableDeletedValue() const { return m_name == hashTableDeletedValue(); }

private:
    void ref() const;
    void deref() const;

    static AtomicStringImpl* hashTableDeletedValue() { return reinterpret_cast<AtomicStringImpl*>(-1); }

    AtomicStringImpl* m_name;
    AtomicStringImpl* m_type;
};

inline bool operator==(const FormElementKey& a, const FormElementKey& b)
{
    return a.name() == b.name() && a.type() == b.type();
}

struct FormElementKeyHash {
    static unsigned hash(const FormElementKey&);
    static bool equal(const FormElementKey& a, const FormElementKey& b) { return a == b; }
    static const bool safeToCompareToEmptyOrDeleted = true;
};

struct FormElementKeyHashTraits : WTF::GenericHashTraits<FormElementKey> {
    static void constructDeletedValue(FormElementKey& slot) { new (&slot) FormElementKey(WTF::HashTableDeletedValue); }
    static bool isDeletedValue(const FormElementKey& value) { return value.isHashTableDeletedValue(); }
};

class Document : public ContainerNode, public ScriptExecutionContext {
public:
    static PassRefPtr<Document> create(Frame* frame)
    {
        return new Document(frame, false);
    }
    static PassRefPtr<Document> createXHTML(Frame* frame)
    {
        return new Document(frame, true);
    }
    virtual ~Document();

    virtual bool isDocument() const { return true; }

    using ContainerNode::ref;
    using ContainerNode::deref;
    virtual void removedLastRef();

    // Nodes belonging to this document hold "self-only" references -
    // these are enough to keep the document from being destroyed, but
    // not enough to keep it from removing its children. This allows a
    // node that outlives its document to still have a valid document
    // pointer without introducing reference cycles

    void selfOnlyRef()
    {
        ASSERT(!m_deletionHasBegun);
        ++m_selfOnlyRefCount;
    }
    void selfOnlyDeref()
    {
        ASSERT(!m_deletionHasBegun);
        --m_selfOnlyRefCount;
        if (!m_selfOnlyRefCount && !refCount()) {
#ifndef NDEBUG
            m_deletionHasBegun = true;
#endif
            delete this;
        }
    }

    // DOM methods & attributes for Document

    DocumentType* doctype() const { return m_docType.get(); }

    DOMImplementation* implementation() const;
    virtual void childrenChanged(bool changedByParser = false, Node* beforeChange = 0, Node* afterChange = 0, int childCountDelta = 0);
    
    Element* documentElement() const
    {
        if (!m_documentElement)
            cacheDocumentElement();
        return m_documentElement.get();
    }
    
    virtual PassRefPtr<Element> createElement(const AtomicString& tagName, ExceptionCode&);
    PassRefPtr<DocumentFragment> createDocumentFragment ();
    PassRefPtr<Text> createTextNode(const String& data);
    PassRefPtr<Comment> createComment(const String& data);
    PassRefPtr<CDATASection> createCDATASection(const String& data, ExceptionCode&);
    PassRefPtr<ProcessingInstruction> createProcessingInstruction(const String& target, const String& data, ExceptionCode&);
    PassRefPtr<Attr> createAttribute(const String& name, ExceptionCode& ec) { return createAttributeNS(String(), name, ec, true); }
    PassRefPtr<Attr> createAttributeNS(const String& namespaceURI, const String& qualifiedName, ExceptionCode&, bool shouldIgnoreNamespaceChecks = false);
    PassRefPtr<EntityReference> createEntityReference(const String& name, ExceptionCode&);
    PassRefPtr<Node> importNode(Node* importedNode, bool deep, ExceptionCode&);
    virtual PassRefPtr<Element> createElementNS(const String& namespaceURI, const String& qualifiedName, ExceptionCode&);
    PassRefPtr<Element> createElement(const QualifiedName&, bool createdByParser);
    Element* getElementById(const AtomicString&) const;
    bool hasElementWithId(AtomicStringImpl* id) const;
    bool containsMultipleElementsWithId(const AtomicString& elementId) { return m_duplicateIds.contains(elementId.impl()); }

    Element* elementFromPoint(int x, int y) const;
    String readyState() const;

    String defaultCharset() const;
    
    // Synonyms backing similar DOM attributes. Use Document::encoding() to avoid virtual dispatch.
    String inputEncoding() const { return Document::encoding(); }
    String charset() const { return Document::encoding(); }
    String characterSet() const { return Document::encoding(); }

    void setCharset(const String&);

    String contentLanguage() const { return m_contentLanguage; }
    void setContentLanguage(const String& lang) { m_contentLanguage = lang; }

    String xmlEncoding() const { return m_xmlEncoding; }
    String xmlVersion() const { return m_xmlVersion; }
    bool xmlStandalone() const { return m_xmlStandalone; }

    void setXMLEncoding(const String& encoding) { m_xmlEncoding = encoding; } // read-only property, only to be set from XMLTokenizer
    void setXMLVersion(const String&, ExceptionCode&);
    void setXMLStandalone(bool, ExceptionCode&);

    String documentURI() const { return m_documentURI; }
    void setDocumentURI(const String&);

    virtual KURL baseURI() const;

    PassRefPtr<Node> adoptNode(PassRefPtr<Node> source, ExceptionCode&);

    PassRefPtr<HTMLCollection> images();
    PassRefPtr<HTMLCollection> embeds();
    PassRefPtr<HTMLCollection> plugins(); // an alias for embeds() required for the JS DOM bindings.
    PassRefPtr<HTMLCollection> applets();
    PassRefPtr<HTMLCollection> links();
    PassRefPtr<HTMLCollection> forms();
    PassRefPtr<HTMLCollection> anchors();
    PassRefPtr<HTMLCollection> all();
    PassRefPtr<HTMLCollection> objects();
    PassRefPtr<HTMLCollection> scripts();
    PassRefPtr<HTMLCollection> windowNamedItems(const String& name);
    PassRefPtr<HTMLCollection> documentNamedItems(const String& name);

    // Find first anchor with the given name.
    // First searches for an element with the given ID, but if that fails, then looks
    // for an anchor with the given name. ID matching is always case sensitive, but
    // Anchor name matching is case sensitive in strict mode and not case sensitive in
    // quirks mode for historical compatibility reasons.
    Element* findAnchor(const String& name);

    HTMLCollection::CollectionInfo* collectionInfo(HTMLCollection::Type type)
    {
        ASSERT(type >= HTMLCollection::FirstUnnamedDocumentCachedType);
        unsigned index = type - HTMLCollection::FirstUnnamedDocumentCachedType;
        ASSERT(index < HTMLCollection::NumUnnamedDocumentCachedTypes);
        return &m_collectionInfo[index]; 
    }

    HTMLCollection::CollectionInfo* nameCollectionInfo(HTMLCollection::Type, const AtomicString& name);

    // DOM methods overridden from  parent classes

    virtual String nodeName() const;
    virtual NodeType nodeType() const;

    // Other methods (not part of DOM)
    virtual bool isHTMLDocument() const { return false; }
    virtual bool isImageDocument() const { return false; }
#if ENABLE(SVG)
    virtual bool isSVGDocument() const { return false; }
#endif
    virtual bool isPluginDocument() const { return false; }
    virtual bool isMediaDocument() const { return false; }
#if ENABLE(WML)
    virtual bool isWMLDocument() const { return false; }
#endif
    virtual bool isFrameSet() const { return false; }
    
    CSSStyleSelector* styleSelector() const { return m_styleSelector; }

    Element* getElementByAccessKey(const String& key) const;
    
    /**
     * Updates the pending sheet count and then calls updateStyleSelector.
     */
    void removePendingSheet();

    /**
     * This method returns true if all top-level stylesheets have loaded (including
     * any @imports that they may be loading).
     */
    bool haveStylesheetsLoaded() const
    {
        return m_pendingStylesheets <= 0 || m_ignorePendingStylesheets;
    }

    /**
     * Increments the number of pending sheets.  The <link> elements
     * invoke this to add themselves to the loading list.
     */
    void addPendingSheet() { m_pendingStylesheets++; }

    void addStyleSheetCandidateNode(Node*, bool createdByParser);
    void removeStyleSheetCandidateNode(Node*);

    bool gotoAnchorNeededAfterStylesheetsLoad() { return m_gotoAnchorNeededAfterStylesheetsLoad; }
    void setGotoAnchorNeededAfterStylesheetsLoad(bool b) { m_gotoAnchorNeededAfterStylesheetsLoad = b; }

    /**
     * Called when one or more stylesheets in the document may have been added, removed or changed.
     *
     * Creates a new style selector and assign it to this document. This is done by iterating through all nodes in
     * document (or those before <BODY> in a HTML document), searching for stylesheets. Stylesheets can be contained in
     * <LINK>, <STYLE> or <BODY> elements, as well as processing instructions (XML documents only). A list is
     * constructed from these which is used to create the a new style selector which collates all of the stylesheets
     * found and is used to calculate the derived styles for all rendering objects.
     */
    void updateStyleSelector();

    void recalcStyleSelector();

    bool usesDescendantRules() const { return m_usesDescendantRules; }
    void setUsesDescendantRules(bool b) { m_usesDescendantRules = b; }
    bool usesSiblingRules() const { return m_usesSiblingRules; }
    void setUsesSiblingRules(bool b) { m_usesSiblingRules = b; }
    bool usesFirstLineRules() const { return m_usesFirstLineRules; }
    void setUsesFirstLineRules(bool b) { m_usesFirstLineRules = b; }
    bool usesFirstLetterRules() const { return m_usesFirstLetterRules; }
    void setUsesFirstLetterRules(bool b) { m_usesFirstLetterRules = b; }
    bool usesBeforeAfterRules() const { return m_usesBeforeAfterRules; }
    void setUsesBeforeAfterRules(bool b) { m_usesBeforeAfterRules = b; }

    // Machinery for saving and restoring state when you leave and then go back to a page.
    void registerFormElementWithState(FormControlElementWithState* e) { m_formElementsWithState.add(e); }
    void unregisterFormElementWithState(FormControlElementWithState* e) { m_formElementsWithState.remove(e); }