xmltokenizerqt.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) 2000 Peter Kelly ([e-mail])
 * Copyright (C) 2005, 2006, 2008 Apple Inc. All rights reserved.
 * Copyright (C) 2006 Alexey Proskuryakov ([e-mail])
 * Copyright (C) 2007 Samuel Weinig ([e-mail])
 * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
 * Copyright (C) 2008 Holger Hans Peter Freyther
 * 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.
 */

#include "config.h"
#include "XMLTokenizer.h"

#include "CDATASection.h"
#include "CString.h"
#include "CachedScript.h"
#include "Comment.h"
#include "DocLoader.h"
#include "Document.h"
#include "DocumentFragment.h"
#include "DocumentType.h"
#include "Frame.h"
#include "FrameLoader.h"
#include "FrameView.h"
#include "HTMLLinkElement.h"
#include "HTMLStyleElement.h"
#include "HTMLTokenizer.h"
#include "ProcessingInstruction.h"
#include "ResourceError.h"
#include "ResourceHandle.h"
#include "ResourceRequest.h"
#include "ResourceResponse.h"
#include "ScriptController.h"
#include "ScriptElement.h"
#include "ScriptSourceCode.h"
#include "ScriptValue.h"
#include "TextResourceDecoder.h"
#include <QDebug>
#include <wtf/Platform.h>
#include <wtf/StringExtras.h>
#include <wtf/Threading.h>
#include <wtf/Vector.h>

using namespace std;

namespace WebCore {

#if QT_VERSION >= 0x040400
class EntityResolver : public QXmlStreamEntityResolver
{
    virtual QString resolveUndeclaredEntity(const QString &name);
};

QString EntityResolver::resolveUndeclaredEntity(const QString &name)
{
    UChar c = decodeNamedEntity(name.toUtf8().constData());
    return QString(c);
}
#endif

// --------------------------------

XMLTokenizer::XMLTokenizer(Document* _doc, FrameView* _view)
    : m_doc(_doc)
    , m_view(_view)
    , m_wroteText(false)
    , m_currentNode(_doc)
    , m_currentNodeIsReferenced(false)
    , m_sawError(false)
    , m_sawXSLTransform(false)
    , m_sawFirstElement(false)
    , m_isXHTMLDocument(false)
    , m_parserPaused(false)
    , m_requestingScript(false)
    , m_finishCalled(false)
    , m_errorCount(0)
    , m_lastErrorLine(0)
    , m_lastErrorColumn(0)
    , m_pendingScript(0)
    , m_scriptStartLine(0)
    , m_parsingFragment(false)
{
#if QT_VERSION >= 0x040400
    m_stream.setEntityResolver(new EntityResolver);
#endif
}

XMLTokenizer::XMLTokenizer(DocumentFragment* fragment, Element* parentElement)
    : m_doc(fragment->document())
    , m_view(0)
    , m_wroteText(false)
    , m_currentNode(fragment)
    , m_currentNodeIsReferenced(fragment)
    , m_sawError(false)
    , m_sawXSLTransform(false)
    , m_sawFirstElement(false)
    , m_isXHTMLDocument(false)
    , m_parserPaused(false)
    , m_requestingScript(false)
    , m_finishCalled(false)
    , m_errorCount(0)
    , m_lastErrorLine(0)
    , m_lastErrorColumn(0)
    , m_pendingScript(0)
    , m_scriptStartLine(0)
    , m_parsingFragment(true)
{
    if (fragment)
        fragment->ref();
    if (m_doc)
        m_doc->ref();
          
    // Add namespaces based on the parent node
    Vector<Element*> elemStack;
    while (parentElement) {
        elemStack.append(parentElement);
        
        Node* n = parentElement->parentNode();
        if (!n || !n->isElementNode())
            break;
        parentElement = static_cast<Element*>(n);
    }
    
    if (elemStack.isEmpty())
        return;
    
#if QT_VERSION < 0x040400
    for (Element* element = elemStack.last(); !elemStack.isEmpty(); elemStack.removeLast()) {
        if (NamedAttrMap* attrs = element->attributes()) {
            for (unsigned i = 0; i < attrs->length(); i++) {
                Attribute* attr = attrs->attributeItem(i);
                if (attr->localName() == "xmlns")
                    m_defaultNamespaceURI = attr->value();
                else if (attr->prefix() == "xmlns")
                    m_prefixToNamespaceMap.set(attr->localName(), attr->value());
            }
        }
    }
#else
    QXmlStreamNamespaceDeclarations namespaces;
    for (Element* element = elemStack.last(); !elemStack.isEmpty(); elemStack.removeLast()) {
        if (NamedAttrMap* attrs = element->attributes()) {
            for (unsigned i = 0; i < attrs->length(); i++) {
                Attribute* attr = attrs->attributeItem(i);
                if (attr->localName() == "xmlns")
                    m_defaultNamespaceURI = attr->value();
                else if (attr->prefix() == "xmlns")
                    namespaces.append(QXmlStreamNamespaceDeclaration(attr->localName(), attr->value()));
            }
        }
    }
    m_stream.addExtraNamespaceDeclarations(namespaces);
    m_stream.setEntityResolver(new EntityResolver);
#endif

    // If the parent element is not in document tree, there may be no xmlns attribute; just default to the parent's namespace.
    if (m_defaultNamespaceURI.isNull() && !parentElement->inDocument())
        m_defaultNamespaceURI = parentElement->namespaceURI();
}

XMLTokenizer::~XMLTokenizer()
{
    setCurrentNode(0);
    if (m_parsingFragment && m_doc)
        m_doc->deref();
    if (m_pendingScript)
        m_pendingScript->removeClient(this);
#if QT_VERSION >= 0x040400
    delete m_stream.entityResolver();
#endif
}

void XMLTokenizer::doWrite(const String& parseString)
{
    m_wroteText = true;

    if (m_doc->decoder() && m_doc->decoder()->sawError()) {
        // If the decoder saw an error, report it as fatal (stops parsing)
        handleError(fatal, "Encoding error", lineNumber(), columnNumber());
        return;
    }

    QString data(parseString);
    if (!data.isEmpty()) {
#if QT_VERSION < 0x040400
        if (!m_sawFirstElement) {
            int idx = data.indexOf(QLatin1String("<?xml"));
            if (idx != -1) {
                int start = idx + 5;
                int end = data.indexOf(QLatin1String("?>"), start);
                QString content = data.mid(start, end-start);
                bool ok = true;
                HashMap<String, String> attrs = parseAttributes(content, ok);
                String version = attrs.get("version");
                String encoding = attrs.get("encoding");
                ExceptionCode ec = 0;
                if (!m_parsingFragment) {
                    if (!version.isEmpty())
                        m_doc->setXMLVersion(version, ec);
                    if (!encoding.isEmpty())
                        m_doc->setXMLEncoding(encoding);
                }
            }
        }
#endif
        m_stream.addData(data);
        parse();
    }

    return;
}

void XMLTokenizer::initializeParserContext(const char* chunk)
{
    m_parserStopped = false;
    m_sawError = false;
    m_sawXSLTransform = false;
    m_sawFirstElement = false;
}

void XMLTokenizer::doEnd()
{
#if ENABLE(XSLT)
    #warning Look at XMLTokenizerLibXml.cpp
#endif

    if (m_stream.error() == QXmlStreamReader::PrematureEndOfDocumentError || (m_wroteText && !m_sawFirstElement)) {
        handleError(fatal, qPrintable(m_stream.errorString()), lineNumber(),
                    columnNumber());
    }
}

#if ENABLE(XSLT)
void* xmlDocPtrForString(DocLoader* docLoader, const String& source, const String& url)
{
    if (source.isEmpty())
        return 0;

    // Parse in a single chunk into an xmlDocPtr
    // FIXME: Hook up error handlers so that a failure to parse the main document results in
    // good error messages.
    const UChar BOM = 0xFEFF;
    const unsigned char BOMHighByte = *reinterpret_cast<const unsigned char*>(&BOM);

    xmlGenericErrorFunc oldErrorFunc = xmlGenericError;
    void* oldErrorContext = xmlGenericErrorContext;
    
    setLoaderForLibXMLCallbacks(docLoader);        
    xmlSetGenericErrorFunc(0, errorFunc);
    
    xmlDocPtr sourceDoc = xmlReadMemory(reinterpret_cast<const char*>(source.characters()),
                                        source.length() * sizeof(UChar),
                                        url.latin1().data(),
                                        BOMHighByte == 0xFF ? "UTF-16LE" : "UTF-16BE", 
                                        XSLT_PARSE_OPTIONS);
    
    setLoaderForLibXMLCallbacks(0);
    xmlSetGenericErrorFunc(oldErrorContext, oldErrorFunc);
    
    return sourceDoc;
}
#endif

int XMLTokenizer::lineNumber() const
{
    return m_stream.lineNumber();
}

int XMLTokenizer::columnNumber() const
{
    return m_stream.columnNumber();
}

void XMLTokenizer::stopParsing()
{
    Tokenizer::stopParsing();
}

void XMLTokenizer::resumeParsing()
{
    ASSERT(m_parserPaused);
    
    m_parserPaused = false;

    // First, execute any pending callbacks
    parse();
    if (m_parserPaused)
        return;

    // Then, write any pending data
    SegmentedString rest = m_pendingSrc;
    m_pendingSrc.clear();
    write(rest, false);

    // Finally, if finish() has been called and write() didn't result
    // in any further callbacks being queued, call end()
    if (m_finishCalled && !m_parserPaused && !m_pendingScript)
        end();
}

bool parseXMLDocumentFragment(const String& chunk, DocumentFragment* fragment, Element* parent)
{
    if (!chunk.length())
        return true;

    XMLTokenizer tokenizer(fragment, parent);
    
    tokenizer.write(String("<qxmlstreamdummyelement>"), false);
    tokenizer.write(chunk, false);
    tokenizer.write(String("</qxmlstreamdummyelement>"), false);
    tokenizer.finish();
    return !tokenizer.hasError();
}

// --------------------------------

struct AttributeParseState {
    HashMap<String, String> attributes;
    bool gotAttributes;
};

static void attributesStartElementNsHandler(AttributeParseState* state, const QXmlStreamAttributes& attrs)
{
    if (attrs.count() <= 0)
        return;

    state->gotAttributes = true;

    for(int i = 0; i < attrs.count(); i++) {
        const QXmlStreamAttribute& attr = attrs[i];
        String attrLocalName = attr.name();
        String attrValue     = attr.value();
        String attrURI       = attr.namespaceUri();
        String attrQName     = attr.qualifiedName();
        state->attributes.set(attrQName, attrValue);
    }
}

HashMap<String, String> parseAttributes(const String& string, bool& attrsOK)
{
    AttributeParseState state;
    state.gotAttributes = false;

    QXmlStreamReader stream;
    QString dummy = QString(QLatin1String("<?xml version=\"1.0\"?><attrs %1 />")).arg(string);
    stream.addData(dummy);
    while (!stream.atEnd()) {
        stream.readNext();
        if (stream.isStartElement()) {
            attributesStartElementNsHandler(&state, stream.attributes());
        }
    }
    attrsOK = state.gotAttributes;
    return state.attributes;
}

static inline String prefixFromQName(const QString& qName)
{
    const int offset = qName.indexOf(QLatin1Char(':'));
    if (offset <= 0)
        return String();
    else
        return qName.left(offset);
}

static inline void handleElementNamespaces(Element* newElement, const QXmlStreamNamespaceDeclarations &ns,
                                           ExceptionCode& ec)
{
    for (int i = 0; i < ns.count(); ++i) {
        const QXmlStreamNamespaceDeclaration &decl = ns[i];
        String namespaceURI = decl.namespaceUri();
        String namespaceQName = decl.prefix().isEmpty() ? String("xmlns") : String("xmlns:") + decl.prefix();
        newElement->setAttributeNS("http://www.w3.org/2000/xmlns/", namespaceQName, namespaceURI, ec);