document.cpp

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/)
 * Copyright (C) 2008 David Levin ([e-mail])
 *
 * 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.
 */

#include "config.h"
#include "Document.h"

#include "AnimationController.h"
#include "AXObjectCache.h"
#include "CDATASection.h"
#include "CSSHelper.h"
#include "CSSStyleSelector.h"
#include "CSSStyleSheet.h"
#include "CSSValueKeywords.h"
#include "CString.h"
#include "CachedCSSStyleSheet.h"
#include "Comment.h"
#include "Console.h"
#include "CookieJar.h"
#include "DOMImplementation.h"
#include "DOMWindow.h"
#include "DocLoader.h"
#include "DocumentFragment.h"
#include "DocumentLoader.h"
#include "DocumentType.h"
#include "EditingText.h"
#include "Editor.h"
#include "EntityReference.h"
#include "Event.h"
#include "EventHandler.h"
#include "EventListener.h"
#include "EventNames.h"
#include "ExceptionCode.h"
#include "FocusController.h"
#include "Frame.h"
#include "FrameLoader.h"
#include "FrameTree.h"
#include "FrameView.h"
#include "HTMLAnchorElement.h"
#include "HTMLBodyElement.h"
#include "HTMLCanvasElement.h"
#include "HTMLDocument.h"
#include "HTMLElementFactory.h"
#include "HTMLFrameOwnerElement.h"
#include "HTMLHeadElement.h"
#include "HTMLInputElement.h"
#include "HTMLLinkElement.h"
#include "HTMLMapElement.h"
#include "HTMLNameCollection.h"
#include "HTMLNames.h"
#include "HTMLStyleElement.h"
#include "HTMLTitleElement.h"
#include "HTTPParsers.h"
#include "HistoryItem.h"
#include "HitTestRequest.h"
#include "HitTestResult.h"
#include "ImageLoader.h"
#include "InspectorController.h"
#include "KeyboardEvent.h"
#include "Logging.h"
#include "MessageEvent.h"
#include "MouseEvent.h"
#include "MouseEventWithHitTestResults.h"
#include "MutationEvent.h"
#include "NameNodeList.h"
#include "NodeFilter.h"
#include "NodeIterator.h"
#include "NodeWithIndex.h"
#include "OverflowEvent.h"
#include "Page.h"
#include "PlatformKeyboardEvent.h"
#include "ProcessingInstruction.h"
#include "ProgressEvent.h"
#include "RegisteredEventListener.h"
#include "RenderArena.h"
#include "RenderTextControl.h"
#include "RenderView.h"
#include "RenderWidget.h"
#include "ScriptController.h"
#include "SecurityOrigin.h"
#include "SegmentedString.h"
#include "SelectionController.h"
#include "Settings.h"
#include "StyleSheetList.h"
#include "TextEvent.h"
#include "TextIterator.h"
#include "TextResourceDecoder.h"
#include "TreeWalker.h"
#include "Timer.h"
#include "UIEvent.h"
#include "WebKitAnimationEvent.h"
#include "WebKitTransitionEvent.h"
#include "WheelEvent.h"
#include "XMLHttpRequest.h"
#include "XMLNames.h"
#include "XMLTokenizer.h"
#include "JSDOMBinding.h"
#include "ScriptController.h"
#include <wtf/CurrentTime.h>
#include <wtf/HashFunctions.h>
#include <wtf/MainThread.h>
#include <wtf/StdLibExtras.h>
#include <wtf/PassRefPtr.h>

#if ENABLE(DATABASE)
#include "Database.h"
#include "DatabaseThread.h"
#endif

#if ENABLE(DOM_STORAGE)
#include "StorageEvent.h"
#endif

#if ENABLE(XPATH)
#include "XPathEvaluator.h"
#include "XPathExpression.h"
#include "XPathNSResolver.h"
#include "XPathResult.h"
#endif

#if ENABLE(XSLT)
#include "XSLTProcessor.h"
#endif

#if ENABLE(XBL)
#include "XBLBindingManager.h"
#endif

#if ENABLE(SVG)
#include "SVGDocumentExtensions.h"
#include "SVGElementFactory.h"
#include "SVGZoomEvent.h"
#include "SVGStyleElement.h"
#endif

#if ENABLE(WML)
#include "WMLDocument.h"
#include "WMLElement.h"
#include "WMLElementFactory.h"
#include "WMLNames.h"
#endif

using namespace std;
using namespace WTF;
using namespace Unicode;

namespace WebCore {

using namespace HTMLNames;

// #define INSTRUMENT_LAYOUT_SCHEDULING 1

// This amount of time must have elapsed before we will even consider scheduling a layout without a delay.
// FIXME: For faster machines this value can really be lowered to 200.  250 is adequate, but a little high
// for dual G5s. :)
static const int cLayoutScheduleThreshold = 250;

// Use 1 to represent the document's default form.
static HTMLFormElement* const defaultForm = reinterpret_cast<HTMLFormElement*>(1);

// DOM Level 2 says (letters added):
//
// a) Name start characters must have one of the categories Ll, Lu, Lo, Lt, Nl.
// b) Name characters other than Name-start characters must have one of the categories Mc, Me, Mn, Lm, or Nd.
// c) Characters in the compatibility area (i.e. with character code greater than #xF900 and less than #xFFFE) are not allowed in XML names.
// d) Characters which have a font or compatibility decomposition (i.e. those with a "compatibility formatting tag" in field 5 of the database -- marked by field 5 beginning with a "<") are not allowed.
// e) The following characters are treated as name-start characters rather than name characters, because the property file classifies them as Alphabetic: [#x02BB-#x02C1], #x0559, #x06E5, #x06E6.
// f) Characters #x20DD-#x20E0 are excluded (in accordance with Unicode, section 5.14).
// g) Character #x00B7 is classified as an extender, because the property list so identifies it.
// h) Character #x0387 is added as a name character, because #x00B7 is its canonical equivalent.
// i) Characters ':' and '_' are allowed as name-start characters.
// j) Characters '-' and '.' are allowed as name characters.
//
// It also contains complete tables. If we decide it's better, we could include those instead of the following code.

static inline bool isValidNameStart(UChar32 c)
{
    // rule (e) above
    if ((c >= 0x02BB && c <= 0x02C1) || c == 0x559 || c == 0x6E5 || c == 0x6E6)
        return true;

    // rule (i) above
    if (c == ':' || c == '_')
        return true;

    // rules (a) and (f) above
    const uint32_t nameStartMask = Letter_Lowercase | Letter_Uppercase | Letter_Other | Letter_Titlecase | Number_Letter;
    if (!(Unicode::category(c) & nameStartMask))
        return false;

    // rule (c) above
    if (c >= 0xF900 && c < 0xFFFE)
        return false;

    // rule (d) above
    DecompositionType decompType = decompositionType(c);
    if (decompType == DecompositionFont || decompType == DecompositionCompat)
        return false;

    return true;
}

static inline bool isValidNamePart(UChar32 c)
{
    // rules (a), (e), and (i) above
    if (isValidNameStart(c))
        return true;

    // rules (g) and (h) above
    if (c == 0x00B7 || c == 0x0387)
        return true;

    // rule (j) above
    if (c == '-' || c == '.')
        return true;

    // rules (b) and (f) above
    const uint32_t otherNamePartMask = Mark_NonSpacing | Mark_Enclosing | Mark_SpacingCombining | Letter_Modifier | Number_DecimalDigit;
    if (!(Unicode::category(c) & otherNamePartMask))
        return false;

    // rule (c) above
    if (c >= 0xF900 && c < 0xFFFE)
        return false;

    // rule (d) above
    DecompositionType decompType = decompositionType(c);
    if (decompType == DecompositionFont || decompType == DecompositionCompat)
        return false;

    return true;
}

static Widget* widgetForNode(Node* focusedNode)
{
    if (!focusedNode)
        return 0;
    RenderObject* renderer = focusedNode->renderer();
    if (!renderer || !renderer->isWidget())
        return 0;
    return static_cast<RenderWidget*>(renderer)->widget();
}

static bool acceptsEditingFocus(Node *node)
{
    ASSERT(node);
    ASSERT(node->isContentEditable());

    Node *root = node->rootEditableElement();
    Frame* frame = node->document()->frame();
    if (!frame || !root)
        return false;

    return frame->editor()->shouldBeginEditing(rangeOfContents(root).get());
}

static HashSet<Document*>* changedDocuments = 0;

Document::Document(Frame* frame, bool isXHTML)
    : ContainerNode(0)
    , m_domtree_version(0)
    , m_styleSheets(StyleSheetList::create(this))
    , m_frameElementsShouldIgnoreScrolling(false)
    , m_title("")
    , m_titleSetExplicitly(false)
    , m_imageLoadEventTimer(this, &Document::imageLoadEventTimerFired)
    , m_updateFocusAppearanceTimer(this, &Document::updateFocusAppearanceTimerFired)
#if ENABLE(XSLT)
    , m_transformSource(0)
#endif
    , m_xmlVersion("1.0")
    , m_xmlStandalone(false)
#if ENABLE(XBL)
    , m_bindingManager(new XBLBindingManager(this))
#endif
    , m_savedRenderer(0)
    , m_secureForms(0)
    , m_designMode(inherit)
    , m_selfOnlyRefCount(0)
#if ENABLE(SVG)
    , m_svgExtensions(0)
#endif
#if ENABLE(DASHBOARD_SUPPORT)
    , m_hasDashboardRegions(false)
    , m_dashboardRegionsDirty(false)
#endif
    , m_accessKeyMapValid(false)
    , m_createRenderers(true)
    , m_inPageCache(false)
    , m_useSecureKeyboardEntryWhenActive(false)
    , m_isXHTML(isXHTML)
    , m_numNodeListCaches(0)
#if ENABLE(DATABASE)
    , m_hasOpenDatabases(false)
#endif
    , m_usingGeolocation(false)
{
    m_document.resetSkippingRef(this);

    m_printing = false;
    
    m_ignoreAutofocus = false;

    m_frame = frame;
    m_renderArena = 0;

    m_axObjectCache = 0;
    
    m_docLoader = new DocLoader(this);

    visuallyOrdered = false;
    m_bParsing = false;
    m_docChanged = false;
    m_tokenizer = 0;
    m_wellFormed = false;

    setParseMode(Strict);

    m_textColor = Color::black;
    m_listenerTypes = 0;
    m_inDocument = true;
    m_inStyleRecalc = false;
    m_closeAfterStyleRecalc = false;
    m_usesDescendantRules = false;
    m_usesSiblingRules = false;
    m_usesFirstLineRules = false;
    m_usesFirstLetterRules = false;
    m_usesBeforeAfterRules = false;
    m_gotoAnchorNeededAfterStylesheetsLoad = false;
 
    m_styleSelector = 0;
    m_didCalculateStyleSelector = false;
    m_pendingStylesheets = 0;
    m_ignorePendingStylesheets = false;
    m_hasNodesWithPlaceholderStyle = false;
    m_pendingSheetLayout = NoLayoutWithPendingSheets;

    m_cssTarget = 0;

    resetLinkColor();
    resetVisitedLinkColor();
    resetActiveLinkColor();

    m_processingLoadEvent = false;
    m_startTime = currentTime();
    m_overMinimumLayoutThreshold = false;
    
    initSecurityContext();
    initDNSPrefetch();

    static int docID = 0;
    m_docID = docID++;
}

void Document::removedLastRef()
{
    ASSERT(!m_deletionHasBegun);
    if (m_selfOnlyRefCount) {
        // If removing a child removes the last self-only ref, we don't
        // want the document to be destructed until after
        // removeAllChildren returns, so we guard ourselves with an
        // extra self-only ref.

        DocPtr<Document> guard(this);

        // We must make sure not to be retaining any of our children through
        // these extra pointers or we will create a reference cycle.
        m_docType = 0;
        m_focusedNode = 0;
        m_hoverNode = 0;
        m_activeNode = 0;
        m_titleElement = 0;
        m_documentElement = 0;

        removeAllChildren();

        deleteAllValues(m_markers);
        m_markers.clear();

        delete m_tokenizer;
        m_tokenizer = 0;

        m_cssCanvasElements.clear();

#ifndef NDEBUG
        m_inRemovedLastRefFunction = false;
#endif
    } else {
#ifndef NDEBUG
        m_deletionHasBegun = true;
#endif
        delete this;
    }
}

Document::~Document()
{
    ASSERT(!renderer());