Ziele Untersuchung
mit Columbo Integrität von
Datenbanken Interaktion und
Portierbarkeit Ergonomie der
Schnittstellen

Angebot Produkte Projekt Beratung

Mittel Analytik Modellierung Sprachen Algebra Logik Hardware Denken Kreativität

Zusammenhänge Gesellschaft Wirtschaft Branche Firma


products/sources/formale Sprachen/C/Firefox/dom/base/ (Browser von der Mozilla Stiftung Version 136.0.1^©) Datei vom 10.2.2025 mit Größe 30 kB

Quelle nsContentSink.cpp Sprache: C

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*
* Base class for the XML and HTML content sinks, which construct a
* DOM based on information from the parser.
*/

#include "nsContentSink.h"
#include "mozilla/Components.h"
#include "mozilla/PresShell.h"
#include "mozilla/StaticPrefs_browser.h"
#include "mozilla/StaticPrefs_content.h"
#include "mozilla/StaticPrefs_network.h"
#include "mozilla/dom/Document.h"
#include "mozilla/dom/LinkStyle.h"
#include "mozilla/dom/ReferrerInfo.h"
#include "mozilla/css/Loader.h"
#include "mozilla/dom/MutationObservers.h"
#include "mozilla/dom/SRILogHelper.h"
#include "mozilla/StoragePrincipalHelper.h"
#include "mozilla/net/HttpBaseChannel.h"
#include "mozilla/net/NeckoChannelParams.h"
#include "nsIDocShell.h"
#include "nsILoadContext.h"
#include "nsIPrefetchService.h"
#include "nsIURI.h"
#include "nsNetUtil.h"
#include "nsIMIMEHeaderParam.h"
#include "nsIProtocolHandler.h"
#include "nsIHttpChannel.h"
#include "nsIContent.h"
#include "nsPresContext.h"
#include "nsViewManager.h"
#include "nsAtom.h"
#include "nsGkAtoms.h"
#include "nsGlobalWindowInner.h"
#include "nsNetCID.h"
#include "nsICookieService.h"
#include "nsContentUtils.h"
#include "nsNodeInfoManager.h"
#include "nsIAppShell.h"
#include "nsIWidget.h"
#include "nsWidgetsCID.h"
#include "mozAutoDocUpdate.h"
#include "nsIWebNavigation.h"
#include "nsGenericHTMLElement.h"
#include "nsIObserverService.h"
#include "mozilla/Preferences.h"
#include "mozilla/ProfilerLabels.h"
#include "mozilla/dom/HTMLDNSPrefetch.h"
#include "mozilla/dom/ServiceWorkerDescriptor.h"
#include "mozilla/dom/ScriptLoader.h"
#include "nsParserConstants.h"
#include "nsSandboxFlags.h"
#include "Link.h"
#include "HTMLLinkElement.h"
#include "MediaList.h"
#include "nsString.h"
#include "nsStringFwd.h"
#include <stdint.h>
#include "mozilla/RefPtr.h"
#include "nsCOMPtr.h"
#include "nsLiteralString.h"
#include "nsIContentPolicy.h"
using namespace mozilla;
using namespace mozilla::css;
using namespace mozilla::dom;

LazyLogModule gContentSinkLogModuleInfo("nscontentsink");

NS_IMPL_CYCLE_COLLECTING_ADDREF(nsContentSink)
NS_IMPL_CYCLE_COLLECTING_RELEASE(nsContentSink)

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsContentSink)
  NS_INTERFACE_MAP_ENTRY(nsICSSLoaderObserver)
  NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
  NS_INTERFACE_MAP_ENTRY(nsIDocumentObserver)
  NS_INTERFACE_MAP_ENTRY(nsIMutationObserver)
  NS_INTERFACE_MAP_ENTRY(nsITimerCallback)
  NS_INTERFACE_MAP_ENTRY(nsINamed)
  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIDocumentObserver)
NS_INTERFACE_MAP_END

NS_IMPL_CYCLE_COLLECTION_CLASS(nsContentSink)

NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsContentSink)
  if (tmp->mDocument) {
    tmp->mDocument->RemoveObserver(tmp);
  }
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mDocument)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mParser)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mDocShell)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mCSSLoader)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mNodeInfoManager)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mScriptLoader)
  NS_IMPL_CYCLE_COLLECTION_UNLINK_WEAK_REFERENCE
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsContentSink)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDocument)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mParser)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDocShell)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mCSSLoader)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mNodeInfoManager)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mScriptLoader)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END

nsContentSink::nsContentSink()
    : mBackoffCount(0),
      mLastNotificationTime(0),
      mLayoutStarted(0),
      mDynamicLowerValue(0),
      mParsing(0),
      mDroppedTimer(0),
      mDeferredLayoutStart(0),
      mDeferredFlushTags(0),
      mIsDocumentObserver(0),
      mRunsToCompletion(0),
      mIsBlockingOnload(false),
      mDeflectedCount(0),
      mHasPendingEvent(false),
      mCurrentParseEndTime(0),
      mBeginLoadTime(0),
      mLastSampledUserEventTime(0),
      mInMonolithicContainer(0),
      mInNotification(0),
      mUpdatesInNotification(0),
      mPendingSheetCount(0) {
  NS_ASSERTION(!mLayoutStarted, "What?");
  NS_ASSERTION(!mDynamicLowerValue, "What?");
  NS_ASSERTION(!mParsing, "What?");
  NS_ASSERTION(mLastSampledUserEventTime == 0, "What?");
  NS_ASSERTION(mDeflectedCount == 0, "What?");
  NS_ASSERTION(!mDroppedTimer, "What?");
  NS_ASSERTION(mInMonolithicContainer == 0, "What?");
  NS_ASSERTION(mInNotification == 0, "What?");
  NS_ASSERTION(!mDeferredLayoutStart, "What?");
}

nsContentSink::~nsContentSink() {
  if (mDocument) {
    // Remove ourselves just to be safe, though we really should have
    // been removed in DidBuildModel if everything worked right.
    mDocument->RemoveObserver(this);
  }
}

nsresult nsContentSink::Init(Document* aDoc, nsIURI* aURI,
                             nsISupports* aContainer, nsIChannel* aChannel) {
  MOZ_ASSERT(aDoc, "null ptr");
  MOZ_ASSERT(aURI, "null ptr");

  if (!aDoc || !aURI) {
    return NS_ERROR_NULL_POINTER;
  }

  mDocument = aDoc;

  mDocumentURI = aURI;
  mDocShell = do_QueryInterface(aContainer);
  mScriptLoader = mDocument->ScriptLoader();

  if (!mRunsToCompletion) {
    if (mDocShell) {
      uint32_t loadType = 0;
      mDocShell->GetLoadType(&loadType);
      mDocument->SetChangeScrollPosWhenScrollingToRef(
          (loadType & nsIDocShell::LOAD_CMD_HISTORY) == 0);
    }

    ProcessHTTPHeaders(aChannel);
  }

  mCSSLoader = aDoc->CSSLoader();

  mNodeInfoManager = aDoc->NodeInfoManager();

  mBackoffCount = StaticPrefs::content_notify_backoffcount();

  if (StaticPrefs::content_sink_enable_perf_mode() != 0) {
    mDynamicLowerValue = StaticPrefs::content_sink_enable_perf_mode() == 1;
  }

  return NS_OK;
}

NS_IMETHODIMP
nsContentSink::StyleSheetLoaded(StyleSheet* aSheet, bool aWasDeferred,
                                nsresult aStatus) {
  MOZ_ASSERT(!mRunsToCompletion, "How come a fragment parser observed sheets?");
  if (aWasDeferred) {
    return NS_OK;
  }
  MOZ_ASSERT(mPendingSheetCount > 0, "How'd that happen?");
  --mPendingSheetCount;

  const bool loadedAllSheets = !mPendingSheetCount;
  if (loadedAllSheets && (mDeferredLayoutStart || mDeferredFlushTags)) {
    if (mDeferredFlushTags) {
      FlushTags();
    }
    if (mDeferredLayoutStart) {
      // We might not have really started layout, since this sheet was still
      // loading.  Do it now.  Probably doesn't matter whether we do this
      // before or after we unblock scripts, but before feels saner.  Note
      // that if mDeferredLayoutStart is true, that means any subclass
      // StartLayout() stuff that needs to happen has already happened, so
      // we don't need to worry about it.
      StartLayout(false);
    }

    // Go ahead and try to scroll to our ref if we have one
    ScrollToRef();
  }

  mScriptLoader->RemoveParserBlockingScriptExecutionBlocker();

  if (loadedAllSheets &&
      mDocument->GetReadyStateEnum() >= Document::READYSTATE_INTERACTIVE) {
    mScriptLoader->DeferCheckpointReached();
  }

  return NS_OK;
}

nsresult nsContentSink::ProcessHTTPHeaders(nsIChannel* aChannel) {
  nsCOMPtr<nsIHttpChannel> httpchannel(do_QueryInterface(aChannel));

  if (!httpchannel) {
    return NS_OK;
  }

  bool gotEarlyHints = false;
  if (nsCOMPtr<mozilla::net::HttpBaseChannel> baseChannel =
          do_QueryInterface(aChannel)) {
    nsTArray<mozilla::net::EarlyHintConnectArgs> earlyHints =
        baseChannel->TakeEarlyHints();
    gotEarlyHints = !earlyHints.IsEmpty();
    mDocument->SetEarlyHints(std::move(earlyHints));
  }

  // Note that the only header we care about is the "link" header, since we
  // have all the infrastructure for kicking off stylesheet loads.

  nsAutoCString linkHeader;

  nsresult rv = httpchannel->GetResponseHeader("link"_ns, linkHeader);
  bool gotLinkHeader = NS_SUCCEEDED(rv) && !linkHeader.IsEmpty();
  if (gotLinkHeader) {
    mDocument->SetHeaderData(nsGkAtoms::link,
                             NS_ConvertASCIItoUTF16(linkHeader));
  }
  if (gotLinkHeader || gotEarlyHints) {
    NS_ASSERTION(!mProcessLinkHeaderEvent.get(),
                 "Already dispatched an event?");

    mProcessLinkHeaderEvent =
        NewNonOwningRunnableMethod("nsContentSink::DoProcessLinkHeader", this,
                                   &nsContentSink::DoProcessLinkHeader);
    rv = NS_DispatchToCurrentThread(mProcessLinkHeaderEvent.get());
    if (NS_FAILED(rv)) {
      mProcessLinkHeaderEvent.Forget();
    }
  }

  return NS_OK;
}

void nsContentSink::DoProcessLinkHeader() {
  for (const auto& earlyHint : mDocument->GetEarlyHints()) {
    ProcessLinkFromHeader(earlyHint.link(), earlyHint.earlyHintPreloaderId());
  }

  nsAutoString value;

  // Getting the header data and parsing the link header together roughly
  // implement <https://httpwg.org/specs/rfc8288.html#parse-set>.
  mDocument->GetHeaderData(nsGkAtoms::link, value);
  auto linkHeaders = net::ParseLinkHeader(value);

  for (const auto& linkHeader : linkHeaders) {
    ProcessLinkFromHeader(linkHeader, 0);
  }
}

nsresult nsContentSink::ProcessLinkFromHeader(const net::LinkHeader& aHeader,
                                              uint64_t aEarlyHintPreloaderId) {
  uint32_t linkTypes = LinkStyle::ParseLinkTypes(aHeader.mRel);

  // The link relation may apply to a different resource, specified
  // in the anchor parameter. For the link relations supported so far,
  // we simply abort if the link applies to a resource different to the
  // one we've loaded
  if (!nsContentUtils::LinkContextIsURI(aHeader.mAnchor,
                                        mDocument->GetDocumentURI())) {
    return NS_OK;
  }

  if (nsContentUtils::PrefetchPreloadEnabled(mDocShell)) {
    // prefetch href if relation is "next" or "prefetch"
    if ((linkTypes & LinkStyle::eNEXT) || (linkTypes & LinkStyle::ePREFETCH)) {
      PrefetchHref(aHeader.mHref, aHeader.mAs, aHeader.mType, aHeader.mMedia);
    }

    if (!aHeader.mHref.IsEmpty() && (linkTypes & LinkStyle::eDNS_PREFETCH)) {
      PrefetchDNS(aHeader.mHref);
    }

    if (!aHeader.mHref.IsEmpty() && (linkTypes & LinkStyle::ePRECONNECT)) {
      Preconnect(aHeader.mHref, aHeader.mCrossOrigin);
    }

    if (linkTypes & LinkStyle::ePRELOAD) {
      PreloadHref(aHeader.mHref, aHeader.mAs, aHeader.mType, aHeader.mMedia,
                  aHeader.mNonce, aHeader.mIntegrity, aHeader.mSrcset,
                  aHeader.mSizes, aHeader.mCrossOrigin, aHeader.mReferrerPolicy,
                  aEarlyHintPreloaderId, aHeader.mFetchPriority);
    }

    if ((linkTypes & LinkStyle::eMODULE_PRELOAD) &&
        mDocument->ScriptLoader()->GetModuleLoader()) {
      PreloadModule(aHeader.mHref, aHeader.mAs, aHeader.mMedia, aHeader.mNonce,
                    aHeader.mIntegrity, aHeader.mCrossOrigin,
                    aHeader.mReferrerPolicy, aEarlyHintPreloaderId,
                    aHeader.mFetchPriority);
    }
  }

  // is it a stylesheet link?
  if (!(linkTypes & LinkStyle::eSTYLESHEET)) {
    return NS_OK;
  }

  bool isAlternate = linkTypes & LinkStyle::eALTERNATE;
  return ProcessStyleLinkFromHeader(aHeader.mHref, isAlternate, aHeader.mTitle,
                                    aHeader.mIntegrity, aHeader.mType,
                                    aHeader.mMedia, aHeader.mReferrerPolicy,
                                    aHeader.mFetchPriority);
}

nsresult nsContentSink::ProcessStyleLinkFromHeader(
    const nsAString& aHref, bool aAlternate, const nsAString& aTitle,
    const nsAString& aIntegrity, const nsAString& aType,
    const nsAString& aMedia, const nsAString& aReferrerPolicy,
    const nsAString& aFetchPriority) {
  if (aAlternate && aTitle.IsEmpty()) {
    // alternates must have title return without error, for now
    return NS_OK;
  }

  nsAutoString mimeType;
  nsAutoString params;
  nsContentUtils::SplitMimeType(aType, mimeType, params);

  // see bug 18817
  if (!mimeType.IsEmpty() && !mimeType.LowerCaseEqualsLiteral("text/css")) {
    // Unknown stylesheet language
    return NS_OK;
  }

  nsCOMPtr<nsIURI> url;
  nsresult rv = NS_NewURI(getter_AddRefs(url), aHref, nullptr,
                          mDocument->GetDocBaseURI());

  if (NS_FAILED(rv)) {
    // The URI is bad, move along, don't propagate the error (for now)
    return NS_OK;
  }

  // Link header is working like a <link> node, so referrerPolicy attr should
  // have higher priority than referrer policy from document.
  ReferrerPolicy policy =
      ReferrerInfo::ReferrerPolicyAttributeFromString(aReferrerPolicy);
  nsCOMPtr<nsIReferrerInfo> referrerInfo =
      ReferrerInfo::CreateFromDocumentAndPolicyOverride(mDocument, policy);

  const FetchPriority fetchPriority =
      nsGenericHTMLElement::ToFetchPriority(aFetchPriority);

  Loader::SheetInfo info{
      *mDocument,
      nullptr,
      url.forget(),
      nullptr,
      referrerInfo.forget(),
      CORS_NONE,
      aTitle,
      aMedia,
      aIntegrity,
      /* nonce = */ u""_ns,
      aAlternate ? Loader::HasAlternateRel::Yes : Loader::HasAlternateRel::No,
      Loader::IsInline::No,
      Loader::IsExplicitlyEnabled::No,
      fetchPriority,
  };

  auto loadResultOrErr =
      mCSSLoader->LoadStyleLink(info, mRunsToCompletion ? nullptr : this);
  if (loadResultOrErr.isErr()) {
    return loadResultOrErr.unwrapErr();
  }

  if (loadResultOrErr.inspect().ShouldBlock() && !mRunsToCompletion) {
    ++mPendingSheetCount;
    mScriptLoader->AddParserBlockingScriptExecutionBlocker();
  }

  return NS_OK;
}

void nsContentSink::PrefetchHref(const nsAString& aHref, const nsAString& aAs,
                                 const nsAString& aType,
                                 const nsAString& aMedia) {
  nsCOMPtr<nsIPrefetchService> prefetchService(components::Prefetch::Service());
  if (prefetchService) {
    // construct URI using document charset
    auto encoding = mDocument->GetDocumentCharacterSet();
    nsCOMPtr<nsIURI> uri;
    NS_NewURI(getter_AddRefs(uri), aHref, encoding, mDocument->GetDocBaseURI());
    if (uri) {
      auto referrerInfo = MakeRefPtr<ReferrerInfo>(*mDocument);
      referrerInfo = referrerInfo->CloneWithNewOriginalReferrer(mDocumentURI);

      prefetchService->PrefetchURI(uri, referrerInfo, mDocument, true);
    }
  }
}

void nsContentSink::PreloadHref(const nsAString& aHref, const nsAString& aAs,
                                const nsAString& aType, const nsAString& aMedia,
                                const nsAString& aNonce,
                                const nsAString& aIntegrity,
                                const nsAString& aSrcset,
                                const nsAString& aSizes, const nsAString& aCORS,
                                const nsAString& aReferrerPolicy,
                                uint64_t aEarlyHintPreloaderId,
                                const nsAString& aFetchPriority) {
  auto encoding = mDocument->GetDocumentCharacterSet();
  nsCOMPtr<nsIURI> uri;
  NS_NewURI(getter_AddRefs(uri), aHref, encoding, mDocument->GetDocBaseURI());
  if (!uri) {
    // URL parsing failed.
    return;
  }

  nsAttrValue asAttr;
  mozilla::net::ParseAsValue(aAs, asAttr);

  nsAutoString mimeType;
  nsAutoString notUsed;
  nsContentUtils::SplitMimeType(aType, mimeType, notUsed);

  auto policyType = mozilla::net::AsValueToContentPolicy(asAttr);
  if (policyType == nsIContentPolicy::TYPE_INVALID ||
      !mozilla::net::CheckPreloadAttrs(asAttr, mimeType, aMedia, mDocument)) {
    // Ignore preload wrong or empty attributes.
    mozilla::net::WarnIgnoredPreload(*mDocument, *uri);
    return;
  }

  mDocument->Preloads().PreloadLinkHeader(
      uri, aHref, policyType, aAs, aType, aNonce, aIntegrity, aSrcset, aSizes,
      aCORS, aReferrerPolicy, aEarlyHintPreloaderId, aFetchPriority);
}

void nsContentSink::PreloadModule(
    const nsAString& aHref, const nsAString& aAs, const nsAString& aMedia,
    const nsAString& aNonce, const nsAString& aIntegrity,
    const nsAString& aCORS, const nsAString& aReferrerPolicy,
    uint64_t aEarlyHintPreloaderId, const nsAString& aFetchPriority) {
  ModuleLoader* moduleLoader = mDocument->ScriptLoader()->GetModuleLoader();

  if (!StaticPrefs::network_modulepreload()) {
    // Keep behavior from https://phabricator.services.mozilla.com/D149371,
    // prior to main implementation of modulepreload
    moduleLoader->DisallowImportMaps();
    return;
  }

  RefPtr<mozilla::dom::MediaList> mediaList =
      mozilla::dom::MediaList::Create(NS_ConvertUTF16toUTF8(aMedia));
  if (!mediaList->Matches(*mDocument)) {
    return;
  }

  if (aHref.IsEmpty()) {
    return;
  }

  if (!net::IsScriptLikeOrInvalid(aAs)) {
    return;
  }

  auto encoding = mDocument->GetDocumentCharacterSet();
  nsCOMPtr<nsIURI> uri;
  NS_NewURI(getter_AddRefs(uri), aHref, encoding, mDocument->GetDocBaseURI());
  if (!uri) {
    return;
  }

  moduleLoader->DisallowImportMaps();

  mDocument->Preloads().PreloadLinkHeader(
      uri, aHref, nsIContentPolicy::TYPE_SCRIPT, u"script"_ns, u"module"_ns,
      aNonce, aIntegrity, u""_ns, u""_ns, aCORS, aReferrerPolicy,
      aEarlyHintPreloaderId, aFetchPriority);
}

void nsContentSink::PrefetchDNS(const nsAString& aHref) {
  nsAutoString hostname;
  bool isHttps = false;

  if (StringBeginsWith(aHref, u"//"_ns)) {
    hostname = Substring(aHref, 2);
  } else {
    nsCOMPtr<nsIURI> uri;
    NS_NewURI(getter_AddRefs(uri), aHref);
    if (!uri) {
      return;
    }
    nsresult rv;
    bool isLocalResource = false;
    rv = NS_URIChainHasFlags(uri, nsIProtocolHandler::URI_IS_LOCAL_RESOURCE,
                             &isLocalResource);
    if (NS_SUCCEEDED(rv) && !isLocalResource) {
      nsAutoCString host;
      uri->GetHost(host);
      CopyUTF8toUTF16(host, hostname);
    }
    isHttps = uri->SchemeIs("https");
  }

  if (!hostname.IsEmpty() && HTMLDNSPrefetch::IsAllowed(mDocument)) {
    OriginAttributes oa;
    StoragePrincipalHelper::GetOriginAttributesForNetworkState(mDocument, oa);

    HTMLDNSPrefetch::Prefetch(hostname, isHttps, oa,
                              mDocument->GetChannel()->GetTRRMode(),
                              HTMLDNSPrefetch::Priority::Low);
  }
}

void nsContentSink::Preconnect(const nsAString& aHref,
                               const nsAString& aCrossOrigin) {
  // construct URI using document charset
  auto encoding = mDocument->GetDocumentCharacterSet();
  nsCOMPtr<nsIURI> uri;
  NS_NewURI(getter_AddRefs(uri), aHref, encoding, mDocument->GetDocBaseURI());

  if (uri && mDocument) {
    mDocument->MaybePreconnect(uri,
                               dom::Element::StringToCORSMode(aCrossOrigin));
  }
}

void nsContentSink::ScrollToRef() {
  RefPtr<Document> document = mDocument;
  document->ScrollToRef();
}

void nsContentSink::StartLayout(bool aIgnorePendingSheets) {
  if (mLayoutStarted) {
    // Nothing to do here
    return;
  }

  mDeferredLayoutStart = true;

  if (!aIgnorePendingSheets &&
      (WaitForPendingSheets() || mDocument->HasPendingInitialTranslation())) {
    // Bail out; we'll start layout when the sheets and l10n load
    return;
  }

  AUTO_PROFILER_LABEL_DYNAMIC_NSCSTRING_RELEVANT_FOR_JS(
      "Layout", LAYOUT, mDocumentURI->GetSpecOrDefault());

  mDeferredLayoutStart = false;

  if (aIgnorePendingSheets) {
    nsContentUtils::ReportToConsole(
        nsIScriptError::warningFlag, "Layout"_ns, mDocument,
        nsContentUtils::eLAYOUT_PROPERTIES, "ForcedLayoutStart");
  }

  // Notify on all our content.  If none of our presshells have started layout
  // yet it'll be a no-op except for updating our data structures, a la
  // UpdateChildCounts() (because we don't want to double-notify on whatever we
  // have right now).  If some of them _have_ started layout, we want to make
  // sure to flush tags instead of just calling UpdateChildCounts() after we
  // loop over the shells.
  FlushTags();

  mLayoutStarted = true;
  mLastNotificationTime = PR_Now();

  mDocument->SetMayStartLayout(true);
  RefPtr<PresShell> presShell = mDocument->GetPresShell();
  // Make sure we don't call Initialize() for a shell that has
  // already called it. This can happen when the layout frame for
  // an iframe is constructed *between* the Embed() call for the
  // docshell in the iframe, and the content sink's call to OpenBody().
  // (Bug 153815)
  if (presShell && !presShell->DidInitialize()) {
    nsresult rv = presShell->Initialize();
    if (NS_FAILED(rv)) {
      return;
    }
  }

  // If the document we are loading has a reference or it is a
  // frameset document, disable the scroll bars on the views.

  mDocument->SetScrollToRef(mDocument->GetDocumentURI());
}

void nsContentSink::NotifyAppend(nsIContent* aContainer, uint32_t aStartIndex) {
  mInNotification++;

  {
    // Scope so we call EndUpdate before we decrease mInNotification
    //
    // Note that aContainer->OwnerDoc() may not be mDocument.
    MOZ_AUTO_DOC_UPDATE(aContainer->OwnerDoc(), true);
    MutationObservers::NotifyContentAppended(
        aContainer, aContainer->GetChildAt_Deprecated(aStartIndex));
    mLastNotificationTime = PR_Now();
  }

  mInNotification--;
}

NS_IMETHODIMP
nsContentSink::Notify(nsITimer* timer) {
  if (mParsing) {
    // We shouldn't interfere with our normal DidProcessAToken logic
    mDroppedTimer = true;
    return NS_OK;
  }

  if (WaitForPendingSheets()) {
    mDeferredFlushTags = true;
  } else {
    FlushTags();

    // Now try and scroll to the reference
    // XXX Should we scroll unconditionally for history loads??
    ScrollToRef();
  }

  mNotificationTimer = nullptr;
  return NS_OK;
}

bool nsContentSink::IsTimeToNotify() {
  if (!StaticPrefs::content_notify_ontimer() || !mLayoutStarted ||
      !mBackoffCount || mInMonolithicContainer) {
    return false;
  }

  if (WaitForPendingSheets()) {
    mDeferredFlushTags = true;
    return false;
  }

  PRTime now = PR_Now();

  int64_t interval = GetNotificationInterval();
  int64_t diff = now - mLastNotificationTime;

  if (diff > interval) {
    mBackoffCount--;
    return true;
  }

  return false;
}

nsresult nsContentSink::WillInterruptImpl() {
  nsresult result = NS_OK;

  SINK_TRACE(static_cast<LogModule*>(gContentSinkLogModuleInfo),
             SINK_TRACE_CALLS, ("nsContentSink::WillInterrupt: this=%p", this));
#ifndef SINK_NO_INCREMENTAL
  if (WaitForPendingSheets()) {
    mDeferredFlushTags = true;
  } else if (StaticPrefs::content_notify_ontimer() && mLayoutStarted) {
    if (mBackoffCount && !mInMonolithicContainer) {
      int64_t now = PR_Now();
      int64_t interval = GetNotificationInterval();
      int64_t diff = now - mLastNotificationTime;

      // If it's already time for us to have a notification
      if (diff > interval || mDroppedTimer) {
        mBackoffCount--;
        SINK_TRACE(static_cast<LogModule*>(gContentSinkLogModuleInfo),
                   SINK_TRACE_REFLOW,
                   ("nsContentSink::WillInterrupt: flushing tags since we've "
                    "run out time; backoff count: %d",
                    mBackoffCount));
        result = FlushTags();
        if (mDroppedTimer) {
          ScrollToRef();
          mDroppedTimer = false;
        }
      } else if (!mNotificationTimer) {
        interval -= diff;
        int32_t delay = interval;

        // Convert to milliseconds
        delay /= PR_USEC_PER_MSEC;

        NS_NewTimerWithCallback(getter_AddRefs(mNotificationTimer), this, delay,
                                nsITimer::TYPE_ONE_SHOT);
        if (mNotificationTimer) {
          SINK_TRACE(static_cast<LogModule*>(gContentSinkLogModuleInfo),
                     SINK_TRACE_REFLOW,
                     ("nsContentSink::WillInterrupt: setting up timer with "
                      "delay %d",
                      delay));
        }
      }
    }
  } else {
    SINK_TRACE(static_cast<LogModule*>(gContentSinkLogModuleInfo),
               SINK_TRACE_REFLOW,
               ("nsContentSink::WillInterrupt: flushing tags "
                "unconditionally"));
    result = FlushTags();
  }
#endif

  mParsing = false;

  return result;
}

void nsContentSink::WillResumeImpl() {
  SINK_TRACE(static_cast<LogModule*>(gContentSinkLogModuleInfo),
             SINK_TRACE_CALLS, ("nsContentSink::WillResume: this=%p", this));

  mParsing = true;
}

nsresult nsContentSink::DidProcessATokenImpl() {
  if (mRunsToCompletion || !mParser) {
    return NS_OK;
  }

  // Get the current user event time
  PresShell* presShell = mDocument->GetPresShell();
  if (!presShell) {
    // If there's no pres shell in the document, return early since
    // we're not laying anything out here.
    return NS_OK;
  }

  // Increase before comparing to gEventProbeRate
  ++mDeflectedCount;

  // Check if there's a pending event
  if (StaticPrefs::content_sink_pending_event_mode() != 0 &&
      !mHasPendingEvent &&
      (mDeflectedCount % StaticPrefs::content_sink_event_probe_rate()) == 0) {
    nsViewManager* vm = presShell->GetViewManager();
    NS_ENSURE_TRUE(vm, NS_ERROR_FAILURE);
    nsCOMPtr<nsIWidget> widget = vm->GetRootWidget();
    mHasPendingEvent = widget && widget->HasPendingInputEvent();
  }

  if (mHasPendingEvent && StaticPrefs::content_sink_pending_event_mode() == 2) {
    return NS_ERROR_HTMLPARSER_INTERRUPTED;
  }

  // Have we processed enough tokens to check time?
  if (!mHasPendingEvent &&
      mDeflectedCount <
          uint32_t(mDynamicLowerValue
                       ? StaticPrefs::content_sink_interactive_deflect_count()
                       : StaticPrefs::content_sink_perf_deflect_count())) {
    return NS_OK;
  }

  mDeflectedCount = 0;

  // Check if it's time to return to the main event loop
  if (PR_IntervalToMicroseconds(PR_IntervalNow()) > mCurrentParseEndTime) {
    return NS_ERROR_HTMLPARSER_INTERRUPTED;
  }

  return NS_OK;
}

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

void nsContentSink::BeginUpdate(Document* aDocument) {
  // Remember nested updates from updates that we started.
  if (mInNotification > 0 && mUpdatesInNotification < 2) {
    ++mUpdatesInNotification;
  }

  // If we're in a script and we didn't do the notification,
  // something else in the script processing caused the
  // notification to occur. Since this could result in frame
  // creation, make sure we've flushed everything before we
  // continue.

  if (!mInNotification++) {
    FlushTags();
  }
}

void nsContentSink::EndUpdate(Document* aDocument) {
  // If we're in a script and we didn't do the notification,
  // something else in the script processing caused the
  // notification to occur. Update our notion of how much
  // has been flushed to include any new content if ending
  // this update leaves us not inside a notification.
  if (!--mInNotification) {
    UpdateChildCounts();
  }
}

void nsContentSink::DidBuildModelImpl(bool aTerminated) {
  MOZ_ASSERT(aTerminated || (mParser && mParser->IsParserClosed()) ||
                 mDocument->GetReadyStateEnum() == Document::READYSTATE_LOADING,
             "Bad readyState");
  mDocument->SetReadyStateInternal(Document::READYSTATE_INTERACTIVE);

  if (mScriptLoader) {
    mScriptLoader->ParsingComplete(aTerminated);
    if (!mPendingSheetCount) {
      mScriptLoader->DeferCheckpointReached();
    }
  }

  if (!mDocument->HaveFiredDOMTitleChange()) {
    mDocument->NotifyPossibleTitleChange(false);
  }

  // Cancel a timer if we had one out there
  if (mNotificationTimer) {
    SINK_TRACE(static_cast<LogModule*>(gContentSinkLogModuleInfo),
               SINK_TRACE_REFLOW,
               ("nsContentSink::DidBuildModel: canceling notification "
                "timeout"));
    mNotificationTimer->Cancel();
    mNotificationTimer = nullptr;
  }
}

void nsContentSink::DropParserAndPerfHint(void) {
  if (!mParser) {
    // Make sure we don't unblock unload too many times
    return;
  }

  // Ref. Bug 49115
  // Do this hack to make sure that the parser
  // doesn't get destroyed, accidently, before
  // the circularity, between sink & parser, is
  // actually broken.
  // Drop our reference to the parser to get rid of a circular
  // reference.
  RefPtr<nsParserBase> kungFuDeathGrip = std::move(mParser);
  mozilla::Unused << kungFuDeathGrip;

  // Call UnblockOnload only if mRunsToComletion is false and if
  // we have already started loading because it's possible that this function
  // is called (i.e. the parser is terminated) before we start loading due to
  // destroying the window inside unload event callbacks for the previous
  // document.
  if (!mRunsToCompletion && mIsBlockingOnload) {
    mDocument->UnblockOnload(true);
    mIsBlockingOnload = false;
  }
}

bool nsContentSink::IsScriptExecutingImpl() {
  return !!mScriptLoader->GetCurrentScript();
}

nsresult nsContentSink::WillParseImpl(void) {
  if (mRunsToCompletion || !mDocument) {
    return NS_OK;
  }

  PresShell* presShell = mDocument->GetPresShell();
  if (!presShell) {
    return NS_OK;
  }

  uint32_t currentTime = PR_IntervalToMicroseconds(PR_IntervalNow());

  if (StaticPrefs::content_sink_enable_perf_mode() == 0) {
    nsViewManager* vm = presShell->GetViewManager();
    NS_ENSURE_TRUE(vm, NS_ERROR_FAILURE);
    uint32_t lastEventTime;
    vm->GetLastUserEventTime(lastEventTime);

    bool newDynLower = mDocument->IsInBackgroundWindow() ||
                       ((currentTime - mBeginLoadTime) >
                            StaticPrefs::content_sink_initial_perf_time() &&
                        (currentTime - lastEventTime) <
                            StaticPrefs::content_sink_interactive_time());

    if (mDynamicLowerValue != newDynLower) {
      mDynamicLowerValue = newDynLower;
    }
  }

  mDeflectedCount = 0;
  mHasPendingEvent = false;

  mCurrentParseEndTime =
      currentTime + (mDynamicLowerValue
                         ? StaticPrefs::content_sink_interactive_parse_time()
                         : StaticPrefs::content_sink_perf_parse_time());

  return NS_OK;
}

void nsContentSink::WillBuildModelImpl() {
  if (!mRunsToCompletion) {
    mDocument->BlockOnload();
    mIsBlockingOnload = true;

    mBeginLoadTime = PR_IntervalToMicroseconds(PR_IntervalNow());
  }

  mDocument->ResetScrolledToRefAlready();

  if (mProcessLinkHeaderEvent.get()) {
    mProcessLinkHeaderEvent.Revoke();

    DoProcessLinkHeader();
  }
}

/* static */
void nsContentSink::NotifyDocElementCreated(Document* aDoc) {
  MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());

  nsCOMPtr<nsIObserverService> observerService =
      mozilla::services::GetObserverService();
  MOZ_ASSERT(observerService);

  auto* win = nsGlobalWindowInner::Cast(aDoc->GetInnerWindow());
  bool fireInitialInsertion = !win || !win->DidFireDocElemInserted();
  if (win) {
    win->SetDidFireDocElemInserted();
  }
  if (fireInitialInsertion) {
    observerService->NotifyObservers(ToSupports(aDoc),
                                     "initial-document-element-inserted", u"");
  }
  observerService->NotifyObservers(ToSupports(aDoc),
                                   "document-element-inserted", u"");

  nsContentUtils::DispatchChromeEvent(aDoc, aDoc, u"DOMDocElementInserted"_ns,
                                      CanBubble::eYes, Cancelable::eNo);
}

NS_IMETHODIMP
nsContentSink::GetName(nsACString& aName) {
  aName.AssignLiteral("nsContentSink_timer");
  return NS_OK;
}

quality99%

¤ Dauer der Verarbeitung: 0.6 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.