gecko-dev/layout/style/Loader.cpp

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/* -*- 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/. */
/* loading of CSS style sheets using the network APIs */
#include "mozilla/css/Loader.h"
#include "mozilla/ArrayUtils.h"
#include "mozilla/dom/DocGroup.h"
#include "mozilla/dom/SRILogHelper.h"
#include "mozilla/IntegerPrintfMacros.h"
#include "mozilla/AutoRestore.h"
#include "mozilla/LoadInfo.h"
#include "mozilla/Logging.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/SystemGroup.h"
#include "mozilla/ResultExtensions.h"
#include "mozilla/URLPreloader.h"
#include "nsIRunnable.h"
#include "nsITimedChannel.h"
#include "nsSyncLoadService.h"
#include "nsCOMPtr.h"
#include "nsString.h"
#include "nsIContent.h"
#include "nsIContentInlines.h"
#include "mozilla/dom/Document.h"
#include "nsIURI.h"
#include "nsNetUtil.h"
#include "nsContentUtils.h"
#include "nsIScriptSecurityManager.h"
#include "nsContentPolicyUtils.h"
#include "nsIHttpChannel.h"
#include "nsIHttpChannelInternal.h"
#include "nsIClassOfService.h"
#include "nsIScriptError.h"
#include "nsMimeTypes.h"
#include "nsIStyleSheetLinkingElement.h"
#include "nsICSSLoaderObserver.h"
#include "nsThreadUtils.h"
#include "nsGkAtoms.h"
#include "nsIThreadInternal.h"
#include "nsINetworkPredictor.h"
#include "nsStringStream.h"
#include "mozilla/dom/MediaList.h"
#include "mozilla/dom/ShadowRoot.h"
#include "mozilla/dom/URL.h"
#include "mozilla/net/UrlClassifierFeatureFactory.h"
#include "mozilla/AsyncEventDispatcher.h"
#include "mozilla/ServoBindings.h"
#include "mozilla/StyleSheet.h"
#include "mozilla/StyleSheetInlines.h"
#include "mozilla/ConsoleReportCollector.h"
#include "mozilla/ServoUtils.h"
#include "mozilla/css/StreamLoader.h"
#include "ReferrerInfo.h"
#ifdef MOZ_XUL
# include "nsXULPrototypeCache.h"
#endif
#include "nsError.h"
#include "mozilla/dom/SRICheck.h"
#include "mozilla/Encoding.h"
using namespace mozilla::dom;
// 1024 bytes is specified in https://drafts.csswg.org/css-syntax/
#define SNIFFING_BUFFER_SIZE 1024
/**
* OVERALL ARCHITECTURE
*
* The CSS Loader gets requests to load various sorts of style sheets:
* inline style from <style> elements, linked style, @import-ed child
* sheets, non-document sheets. The loader handles the following tasks:
* 1) Creation of the actual style sheet objects: CreateSheet()
* 2) setting of the right media, title, enabled state, etc on the
* sheet: PrepareSheet()
* 3) Insertion of the sheet in the proper cascade order:
* InsertSheetInTree() and InsertChildSheet()
* 4) Load of the sheet: LoadSheet() including security checks
* 5) Parsing of the sheet: ParseSheet()
* 6) Cleanup: SheetComplete()
*
* The detailed documentation for these functions is found with the
* function implementations.
*
* The following helper object is used:
* SheetLoadData -- a small class that is used to store all the
* information needed for the loading of a sheet;
* this class handles listening for the stream
* loader completion and also handles charset
* determination.
*/
static mozilla::LazyLogModule sCssLoaderLog("nsCSSLoader");
static mozilla::LazyLogModule gSriPRLog("SRI");
#define LOG_ERROR(args) MOZ_LOG(sCssLoaderLog, mozilla::LogLevel::Error, args)
#define LOG_WARN(args) MOZ_LOG(sCssLoaderLog, mozilla::LogLevel::Warning, args)
#define LOG_DEBUG(args) MOZ_LOG(sCssLoaderLog, mozilla::LogLevel::Debug, args)
#define LOG(args) LOG_DEBUG(args)
#define LOG_ERROR_ENABLED() \
MOZ_LOG_TEST(sCssLoaderLog, mozilla::LogLevel::Error)
#define LOG_WARN_ENABLED() \
MOZ_LOG_TEST(sCssLoaderLog, mozilla::LogLevel::Warning)
#define LOG_DEBUG_ENABLED() \
MOZ_LOG_TEST(sCssLoaderLog, mozilla::LogLevel::Debug)
#define LOG_ENABLED() LOG_DEBUG_ENABLED()
#define LOG_URI(format, uri) \
PR_BEGIN_MACRO \
NS_ASSERTION(uri, "Logging null uri"); \
if (LOG_ENABLED()) { \
LOG((format, uri->GetSpecOrDefault().get())); \
} \
PR_END_MACRO
// And some convenience strings...
static const char* const gStateStrings[] = {"Unknown", "NeedsParser", "Pending",
"Loading", "Complete"};
namespace mozilla {
class SheetLoadDataHashKey : public nsURIHashKey {
public:
typedef SheetLoadDataHashKey* KeyType;
typedef const SheetLoadDataHashKey* KeyTypePointer;
explicit SheetLoadDataHashKey(const SheetLoadDataHashKey* aKey)
: nsURIHashKey(aKey->mKey),
mPrincipal(aKey->mPrincipal),
mReferrerInfo(aKey->mReferrerInfo),
mCORSMode(aKey->mCORSMode),
mParsingMode(aKey->mParsingMode) {
MOZ_COUNT_CTOR(SheetLoadDataHashKey);
}
SheetLoadDataHashKey(nsIURI* aURI, nsIPrincipal* aPrincipal,
nsIReferrerInfo* aReferrerInfo, CORSMode aCORSMode,
css::SheetParsingMode aParsingMode)
: nsURIHashKey(aURI),
mPrincipal(aPrincipal),
mReferrerInfo(aReferrerInfo),
mCORSMode(aCORSMode),
mParsingMode(aParsingMode) {
MOZ_COUNT_CTOR(SheetLoadDataHashKey);
}
SheetLoadDataHashKey(SheetLoadDataHashKey&& toMove)
: nsURIHashKey(std::move(toMove)),
mPrincipal(std::move(toMove.mPrincipal)),
mReferrerInfo(std::move(toMove.mReferrerInfo)),
mCORSMode(std::move(toMove.mCORSMode)),
mParsingMode(std::move(toMove.mParsingMode)) {
MOZ_COUNT_CTOR(SheetLoadDataHashKey);
}
explicit SheetLoadDataHashKey(css::SheetLoadData&);
MOZ_COUNTED_DTOR(SheetLoadDataHashKey)
SheetLoadDataHashKey* GetKey() const {
return const_cast<SheetLoadDataHashKey*>(this);
}
const SheetLoadDataHashKey* GetKeyPointer() const { return this; }
bool KeyEquals(const SheetLoadDataHashKey* aKey) const {
if (!nsURIHashKey::KeyEquals(aKey->mKey)) {
return false;
}
if (!mPrincipal != !aKey->mPrincipal) {
// One or the other has a principal, but not both... not equal
return false;
}
if (mCORSMode != aKey->mCORSMode) {
// Different CORS modes; we don't match
return false;
}
if (mParsingMode != aKey->mParsingMode) {
return false;
}
bool eq;
if (NS_FAILED(mReferrerInfo->Equals(aKey->mReferrerInfo, &eq)) || !eq) {
return false;
}
return !mPrincipal ||
(NS_SUCCEEDED(mPrincipal->Equals(aKey->mPrincipal, &eq)) && eq);
}
static const SheetLoadDataHashKey* KeyToPointer(SheetLoadDataHashKey* aKey) {
return aKey;
}
static PLDHashNumber HashKey(const SheetLoadDataHashKey* aKey) {
return nsURIHashKey::HashKey(aKey->mKey);
}
nsIURI* GetURI() const { return nsURIHashKey::GetKey(); }
nsIPrincipal* GetPrincipal() const { return mPrincipal; }
css::SheetParsingMode ParsingMode() const { return mParsingMode; }
enum { ALLOW_MEMMOVE = true };
protected:
nsCOMPtr<nsIPrincipal> mPrincipal;
nsCOMPtr<nsIReferrerInfo> mReferrerInfo;
CORSMode mCORSMode;
css::SheetParsingMode mParsingMode;
};
SheetLoadDataHashKey::SheetLoadDataHashKey(css::SheetLoadData& aLoadData)
: nsURIHashKey(aLoadData.mURI),
mPrincipal(aLoadData.mLoaderPrincipal),
mReferrerInfo(aLoadData.ReferrerInfo()),
mCORSMode(aLoadData.mSheet->GetCORSMode()),
mParsingMode(aLoadData.mSheet->ParsingMode()) {
MOZ_COUNT_CTOR(SheetLoadDataHashKey);
}
} // namespace mozilla
namespace mozilla {
namespace css {
/********************************
* SheetLoadData implementation *
********************************/
NS_IMPL_ISUPPORTS(SheetLoadData, nsIRunnable, nsIThreadObserver)
SheetLoadData::SheetLoadData(
Loader* aLoader, const nsAString& aTitle, nsIURI* aURI, StyleSheet* aSheet,
bool aSyncLoad, nsIStyleSheetLinkingElement* aOwningElement,
IsAlternate aIsAlternate, MediaMatched aMediaMatches,
nsICSSLoaderObserver* aObserver, nsIPrincipal* aLoaderPrincipal,
nsIReferrerInfo* aReferrerInfo, nsINode* aRequestingNode)
: mLoader(aLoader),
mTitle(aTitle),
mEncoding(nullptr),
mURI(aURI),
mLineNumber(1),
mSheet(aSheet),
mNext(nullptr),
mPendingChildren(0),
mSyncLoad(aSyncLoad),
mIsNonDocumentSheet(false),
mIsLoading(false),
mIsBeingParsed(false),
mIsCancelled(false),
mMustNotify(false),
mWasAlternate(aIsAlternate == IsAlternate::Yes),
mMediaMatched(aMediaMatches == MediaMatched::Yes),
mUseSystemPrincipal(false),
mSheetAlreadyComplete(false),
mIsCrossOriginNoCORS(false),
mBlockResourceTiming(false),
mLoadFailed(false),
mOwningElement(aOwningElement),
mObserver(aObserver),
mLoaderPrincipal(aLoaderPrincipal),
mReferrerInfo(aReferrerInfo),
mRequestingNode(aRequestingNode),
mPreloadEncoding(nullptr) {
MOZ_ASSERT(mLoader, "Must have a loader!");
}
SheetLoadData::SheetLoadData(Loader* aLoader, nsIURI* aURI, StyleSheet* aSheet,
SheetLoadData* aParentData,
nsICSSLoaderObserver* aObserver,
nsIPrincipal* aLoaderPrincipal,
nsIReferrerInfo* aReferrerInfo,
nsINode* aRequestingNode)
: mLoader(aLoader),
mEncoding(nullptr),
mURI(aURI),
mLineNumber(1),
mSheet(aSheet),
mNext(nullptr),
mParentData(aParentData),
mPendingChildren(0),
mSyncLoad(false),
mIsNonDocumentSheet(false),
mIsLoading(false),
mIsBeingParsed(false),
mIsCancelled(false),
mMustNotify(false),
mWasAlternate(false),
mMediaMatched(true),
mUseSystemPrincipal(false),
mSheetAlreadyComplete(false),
mIsCrossOriginNoCORS(false),
mBlockResourceTiming(false),
mLoadFailed(false),
mOwningElement(nullptr),
mObserver(aObserver),
mLoaderPrincipal(aLoaderPrincipal),
mReferrerInfo(aReferrerInfo),
mRequestingNode(aRequestingNode),
mPreloadEncoding(nullptr) {
MOZ_ASSERT(mLoader, "Must have a loader!");
if (mParentData) {
mSyncLoad = mParentData->mSyncLoad;
mIsNonDocumentSheet = mParentData->mIsNonDocumentSheet;
mUseSystemPrincipal = mParentData->mUseSystemPrincipal;
++(mParentData->mPendingChildren);
}
MOZ_ASSERT(!mUseSystemPrincipal || mSyncLoad,
"Shouldn't use system principal for async loads");
}
SheetLoadData::SheetLoadData(Loader* aLoader, nsIURI* aURI, StyleSheet* aSheet,
bool aSyncLoad, bool aUseSystemPrincipal,
const Encoding* aPreloadEncoding,
nsICSSLoaderObserver* aObserver,
nsIPrincipal* aLoaderPrincipal,
nsIReferrerInfo* aReferrerInfo,
nsINode* aRequestingNode)
: mLoader(aLoader),
mEncoding(nullptr),
mURI(aURI),
mLineNumber(1),
mSheet(aSheet),
mNext(nullptr),
mPendingChildren(0),
mSyncLoad(aSyncLoad),
mIsNonDocumentSheet(true),
mIsLoading(false),
mIsBeingParsed(false),
mIsCancelled(false),
mMustNotify(false),
mWasAlternate(false),
mMediaMatched(true),
mUseSystemPrincipal(aUseSystemPrincipal),
mSheetAlreadyComplete(false),
mIsCrossOriginNoCORS(false),
mBlockResourceTiming(false),
mLoadFailed(false),
mOwningElement(nullptr),
mObserver(aObserver),
mLoaderPrincipal(aLoaderPrincipal),
mReferrerInfo(aReferrerInfo),
mRequestingNode(aRequestingNode),
mPreloadEncoding(aPreloadEncoding) {
MOZ_ASSERT(mLoader, "Must have a loader!");
MOZ_ASSERT(!mUseSystemPrincipal || mSyncLoad,
"Shouldn't use system principal for async loads");
}
SheetLoadData::~SheetLoadData() {
MOZ_DIAGNOSTIC_ASSERT(mSheetCompleteCalled,
"Should always call SheetComplete");
// Do this iteratively to avoid blowing up the stack.
RefPtr<SheetLoadData> next = std::move(mNext);
while (next) {
next = std::move(next->mNext);
}
}
NS_IMETHODIMP
SheetLoadData::Run() {
mLoader->HandleLoadEvent(*this);
return NS_OK;
}
NS_IMETHODIMP
SheetLoadData::OnDispatchedEvent() { return NS_OK; }
NS_IMETHODIMP
SheetLoadData::OnProcessNextEvent(nsIThreadInternal* aThread, bool aMayWait) {
// XXXkhuey this is insane!
// We want to fire our load even before or after event processing,
// whichever comes first.
FireLoadEvent(aThread);
return NS_OK;
}
NS_IMETHODIMP
SheetLoadData::AfterProcessNextEvent(nsIThreadInternal* aThread,
bool aEventWasProcessed) {
// XXXkhuey this too!
// We want to fire our load even before or after event processing,
// whichever comes first.
FireLoadEvent(aThread);
return NS_OK;
}
void SheetLoadData::FireLoadEvent(nsIThreadInternal* aThread) {
// First remove ourselves as a thread observer. But we need to keep
// ourselves alive while doing that!
RefPtr<SheetLoadData> kungFuDeathGrip(this);
aThread->RemoveObserver(this);
// Now fire the event
nsCOMPtr<nsINode> node = do_QueryInterface(mOwningElement);
NS_ASSERTION(node, "How did that happen???");
nsContentUtils::DispatchTrustedEvent(
node->OwnerDoc(), node,
mLoadFailed ? NS_LITERAL_STRING("error") : NS_LITERAL_STRING("load"),
CanBubble::eNo, Cancelable::eNo);
// And unblock onload
mLoader->UnblockOnload(true);
}
void SheetLoadData::ScheduleLoadEventIfNeeded() {
if (!mOwningElement) {
return;
}
nsCOMPtr<nsIThread> thread = do_GetCurrentThread();
nsCOMPtr<nsIThreadInternal> internalThread = do_QueryInterface(thread);
if (NS_SUCCEEDED(internalThread->AddObserver(this))) {
// Make sure to block onload here
mLoader->BlockOnload();
}
}
/*********************
* Style sheet reuse *
*********************/
bool LoaderReusableStyleSheets::FindReusableStyleSheet(
nsIURI* aURL, RefPtr<StyleSheet>& aResult) {
MOZ_ASSERT(aURL);
for (size_t i = mReusableSheets.Length(); i > 0; --i) {
size_t index = i - 1;
bool sameURI;
MOZ_ASSERT(mReusableSheets[index]->GetOriginalURI());
nsresult rv =
aURL->Equals(mReusableSheets[index]->GetOriginalURI(), &sameURI);
if (!NS_FAILED(rv) && sameURI) {
aResult = mReusableSheets[index];
mReusableSheets.RemoveElementAt(index);
return true;
}
}
return false;
}
// A struct keeping alive various records of sheets that are loading, deferred,
// or already loaded (the later one for caching purposes).
struct Loader::Sheets {
nsRefPtrHashtable<SheetLoadDataHashKey, StyleSheet> mCompleteSheets;
nsRefPtrHashtable<SheetLoadDataHashKey, SheetLoadData> mPendingDatas;
// The SheetLoadData pointers in mLoadingDatas below are weak references.
nsDataHashtable<SheetLoadDataHashKey, SheetLoadData*> mLoadingDatas;
nsRefPtrHashtable<nsStringHashKey, StyleSheet> mInlineSheets;
RefPtr<StyleSheet> LookupInline(const nsAString&);
// A cache hit or miss. It is a miss if the `StyleSheet` is null.
using CacheResult = Tuple<RefPtr<StyleSheet>, SheetState>;
CacheResult Lookup(SheetLoadDataHashKey&, bool aSyncLoad);
size_t SizeOfIncludingThis(MallocSizeOf) const;
};
RefPtr<StyleSheet> Loader::Sheets::LookupInline(const nsAString& aBuffer) {
auto result = mInlineSheets.Lookup(aBuffer);
if (!result) {
return nullptr;
}
if (result.Data()->HasModifiedRules()) {
// Remove it now that we know that we're never going to use this stylesheet
// again.
result.Remove();
return nullptr;
}
return result.Data()->Clone(nullptr, nullptr, nullptr, nullptr);
}
static void AssertComplete(const StyleSheet& aSheet) {
// This sheet came from the XUL cache or our per-document hashtable; it
// better be a complete sheet.
MOZ_ASSERT(aSheet.IsComplete(),
"Sheet thinks it's not complete while we think it is");
}
static void AssertIncompleteSheetMatches(const SheetLoadData& aData,
const SheetLoadDataHashKey& aKey) {
#ifdef DEBUG
bool debugEqual;
MOZ_ASSERT((!aKey.GetPrincipal() && !aData.mLoaderPrincipal) ||
(aKey.GetPrincipal() && aData.mLoaderPrincipal &&
NS_SUCCEEDED(aKey.GetPrincipal()->Equals(
aData.mLoaderPrincipal, &debugEqual)) &&
debugEqual),
"Principals should be the same");
#endif
MOZ_ASSERT(!aData.mSheet->HasForcedUniqueInner(),
"CSSOM shouldn't allow access to incomplete sheets");
}
auto Loader::Sheets::Lookup(SheetLoadDataHashKey& aKey, bool aSyncLoad)
-> CacheResult {
auto CloneSheet = [](StyleSheet& aSheet) -> RefPtr<StyleSheet> {
return aSheet.Clone(nullptr, nullptr, nullptr, nullptr);
};
nsIURI* uri = aKey.GetURI();
// Try to find first in the XUL prototype cache.
#ifdef MOZ_XUL
if (IsChromeURI(uri)) {
nsXULPrototypeCache* cache = nsXULPrototypeCache::GetInstance();
if (cache && cache->IsEnabled()) {
if (StyleSheet* sheet = cache->GetStyleSheet(uri)) {
LOG((" From XUL cache: %p", sheet));
AssertComplete(*sheet);
// We need to check the parsing mode manually because the XUL cache only
// keys off the URI. See below for the unique inner check.
if (!sheet->HasModifiedRules() &&
sheet->ParsingMode() == aKey.ParsingMode()) {
return MakeTuple(CloneSheet(*sheet), SheetState::Complete);
}
LOG(
(" Not cloning due to forced unique inner or mismatched "
"parsing mode"));
}
}
}
#endif
// Now complete sheets.
if (auto lookup = mCompleteSheets.Lookup(&aKey)) {
LOG((" From completed: %p", lookup.Data().get()));
AssertComplete(*lookup.Data());
MOZ_ASSERT(lookup.Data()->ParsingMode() == aKey.ParsingMode());
// Make sure the stylesheet hasn't been modified, as otherwise it may not
// contain the rules we care about.
if (!lookup.Data()->HasModifiedRules()) {
RefPtr<StyleSheet>& cachedSheet = lookup.Data();
RefPtr<StyleSheet> clone = CloneSheet(*cachedSheet);
MOZ_ASSERT(!clone->HasForcedUniqueInner());
MOZ_ASSERT(!clone->HasModifiedRules());
const bool oldSheetIsWorthKeeping = ([&cachedSheet] {
// If our current stylesheet in the cache has been touched by CSSOM, we
// need to do a full copy of it. The new clone still hasn't been
// touched, so we have better odds of doing a less-expensive clone in
// the future.
if (cachedSheet->HasForcedUniqueInner()) {
return false;
}
// The sheet we're cloning isn't actually referenced by anyone. Replace
// it in the cache, so that if our CSSOM is later modified we don't end
// up with two copies of our inner hanging around.
if (!cachedSheet->GetOwnerNode() && !cachedSheet->GetParentSheet()) {
return false;
}
return true;
}());
if (!oldSheetIsWorthKeeping) {
cachedSheet = clone;
}
return MakeTuple(std::move(clone), SheetState::Complete);
}
LOG((" Not cloning due to modified rules"));
// Remove it now that we know that we're never going to use this stylesheet
// again.
lookup.Remove();
}
if (aSyncLoad) {
return {};
}
if (SheetLoadData* data = mLoadingDatas.Get(&aKey)) {
LOG((" From loading: %p", data->mSheet.get()));
AssertIncompleteSheetMatches(*data, aKey);
return MakeTuple(CloneSheet(*data->mSheet), SheetState::Loading);
}
if (SheetLoadData* data = mPendingDatas.GetWeak(&aKey)) {
LOG((" From pending: %p", data->mSheet.get()));
AssertIncompleteSheetMatches(*data, aKey);
return MakeTuple(CloneSheet(*data->mSheet), SheetState::Pending);
}
return {};
}
size_t Loader::Sheets::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const {
size_t n = aMallocSizeOf(this);
n += mCompleteSheets.ShallowSizeOfExcludingThis(aMallocSizeOf);
for (auto iter = mCompleteSheets.ConstIter(); !iter.Done(); iter.Next()) {
// If the sheet has a parent, then its parent will report it so we don't
// have to worry about it here. Likewise, if aSheet has an owning node, then
// the document that node is in will report it.
const StyleSheet* sheet = iter.UserData();
if (!sheet->GetOwnerNode() && !sheet->GetParentSheet()) {
n += sheet->SizeOfIncludingThis(aMallocSizeOf);
}
}
n += mInlineSheets.ShallowSizeOfExcludingThis(aMallocSizeOf);
for (auto iter = mInlineSheets.ConstIter(); !iter.Done(); iter.Next()) {
n += iter.Key().SizeOfExcludingThisIfUnshared(aMallocSizeOf);
// If the sheet has a parent, then its parent will report it so we don't
// have to worry about it here.
const StyleSheet* sheet = iter.UserData();
MOZ_ASSERT(!sheet->GetParentSheet(),
"How did an @import rule end up here?");
if (!sheet->GetOwnerNode()) {
n += sheet->SizeOfIncludingThis(aMallocSizeOf);
}
}
// Measurement of the following members may be added later if DMD finds it is
// worthwhile:
// - mLoadingDatas: transient, and should be small
// - mPendingDatas: transient, and should be small
return n;
}
/*************************
* Loader Implementation *
*************************/
Loader::Loader()
: mDocument(nullptr),
mDatasToNotifyOn(0),
mCompatMode(eCompatibility_FullStandards),
mEnabled(true),
mReporter(new ConsoleReportCollector()) {}
Loader::Loader(DocGroup* aDocGroup) : Loader() { mDocGroup = aDocGroup; }
Loader::Loader(Document* aDocument) : Loader() {
MOZ_ASSERT(aDocument, "We should get a valid document from the caller!");
mDocument = aDocument;
mCompatMode = aDocument->GetCompatibilityMode();
}
Loader::~Loader() {
NS_ASSERTION(!mSheets || mSheets->mLoadingDatas.Count() == 0,
"How did we get destroyed when there are loading data?");
NS_ASSERTION(!mSheets || mSheets->mPendingDatas.Count() == 0,
"How did we get destroyed when there are pending data?");
// Note: no real need to revoke our stylesheet loaded events -- they
// hold strong references to us, so if we're going away that means
// they're all done.
}
void Loader::DropDocumentReference(void) {
mDocument = nullptr;
// Flush out pending datas just so we don't leak by accident. These
// loads should short-circuit through the mDocument check in
// LoadSheet and just end up in SheetComplete immediately
if (mSheets) {
StartDeferredLoads();
}
}
void Loader::DocumentStyleSheetSetChanged() {
MOZ_ASSERT(mDocument);
// start any pending alternates that aren't alternates anymore
if (!mSheets) {
return;
}
LoadDataArray arr(mSheets->mPendingDatas.Count());
for (auto iter = mSheets->mPendingDatas.Iter(); !iter.Done(); iter.Next()) {
RefPtr<SheetLoadData>& data = iter.Data();
MOZ_ASSERT(data, "Must have a data");
// Note that we don't want to affect what the selected style set is, so
// use true for aHasAlternateRel.
auto isAlternate = data->mLoader->IsAlternateSheet(data->mTitle, true);
if (isAlternate == IsAlternate::No) {
arr.AppendElement(std::move(data));
iter.Remove();
}
}
mDatasToNotifyOn += arr.Length();
for (RefPtr<SheetLoadData>& data : arr) {
--mDatasToNotifyOn;
LoadSheet(*data, SheetState::NeedsParser, IsPreload::No);
}
}
static const char kCharsetSym[] = "@charset \"";
static bool GetCharsetFromData(const char* aStyleSheetData,
uint32_t aDataLength, nsACString& aCharset) {
aCharset.Truncate();
if (aDataLength <= sizeof(kCharsetSym) - 1) return false;
if (strncmp(aStyleSheetData, kCharsetSym, sizeof(kCharsetSym) - 1)) {
return false;
}
for (uint32_t i = sizeof(kCharsetSym) - 1; i < aDataLength; ++i) {
char c = aStyleSheetData[i];
if (c == '"') {
++i;
if (i < aDataLength && aStyleSheetData[i] == ';') {
return true;
}
// fail
break;
}
aCharset.Append(c);
}
// Did not see end quote or semicolon
aCharset.Truncate();
return false;
}
NotNull<const Encoding*> SheetLoadData::DetermineNonBOMEncoding(
nsACString const& aSegment, nsIChannel* aChannel) {
const Encoding* encoding;
nsAutoCString label;
// Check HTTP
if (aChannel && NS_SUCCEEDED(aChannel->GetContentCharset(label))) {
encoding = Encoding::ForLabel(label);
if (encoding) {
return WrapNotNull(encoding);
}
}
// Check @charset
auto sniffingLength = aSegment.Length();
if (sniffingLength > SNIFFING_BUFFER_SIZE) {
sniffingLength = SNIFFING_BUFFER_SIZE;
}
if (GetCharsetFromData(aSegment.BeginReading(), sniffingLength, label)) {
encoding = Encoding::ForLabel(label);
if (encoding == UTF_16BE_ENCODING || encoding == UTF_16LE_ENCODING) {
return UTF_8_ENCODING;
}
if (encoding) {
return WrapNotNull(encoding);
}
}
// Now try the charset on the <link> or processing instruction
// that loaded us
if (mOwningElement) {
nsAutoString label16;
mOwningElement->GetCharset(label16);
encoding = Encoding::ForLabel(label16);
if (encoding) {
return WrapNotNull(encoding);
}
}
// In the preload case, the value of the charset attribute on <link> comes
// in via mPreloadEncoding instead.
if (mPreloadEncoding) {
return WrapNotNull(mPreloadEncoding);
}
// Try charset from the parent stylesheet.
if (mParentData) {
encoding = mParentData->mEncoding;
if (encoding) {
return WrapNotNull(encoding);
}
}
if (mLoader->mDocument) {
// Use the document charset.
return mLoader->mDocument->GetDocumentCharacterSet();
}
return UTF_8_ENCODING;
}
static nsresult VerifySheetIntegrity(const SRIMetadata& aMetadata,
nsIChannel* aChannel,
const nsACString& aFirst,
const nsACString& aSecond,
const nsACString& aSourceFileURI,
nsIConsoleReportCollector* aReporter) {
NS_ENSURE_ARG_POINTER(aReporter);
if (MOZ_LOG_TEST(SRILogHelper::GetSriLog(), LogLevel::Debug)) {
nsAutoCString requestURL;
nsCOMPtr<nsIURI> originalURI;
if (aChannel &&
NS_SUCCEEDED(aChannel->GetOriginalURI(getter_AddRefs(originalURI))) &&
originalURI) {
originalURI->GetAsciiSpec(requestURL);
}
MOZ_LOG(SRILogHelper::GetSriLog(), LogLevel::Debug,
("VerifySheetIntegrity (unichar stream)"));
}
SRICheckDataVerifier verifier(aMetadata, aSourceFileURI, aReporter);
nsresult rv =
verifier.Update(aFirst.Length(), (const uint8_t*)aFirst.BeginReading());
NS_ENSURE_SUCCESS(rv, rv);
rv =
verifier.Update(aSecond.Length(), (const uint8_t*)aSecond.BeginReading());
NS_ENSURE_SUCCESS(rv, rv);
return verifier.Verify(aMetadata, aChannel, aSourceFileURI, aReporter);
}
/*
* Stream completion code shared by Stylo and the old style system.
*
* Here we need to check that the load did not give us an http error
* page and check the mimetype on the channel to make sure we're not
* loading non-text/css data in standards mode.
*/
nsresult SheetLoadData::VerifySheetReadyToParse(nsresult aStatus,
const nsACString& aBytes1,
const nsACString& aBytes2,
nsIChannel* aChannel) {
LOG(("SheetLoadData::VerifySheetReadyToParse"));
NS_ASSERTION(!mLoader->mSyncCallback, "Synchronous callback from necko");
if (mIsCancelled) {
// Just return. Don't call SheetComplete -- it's already been
// called and calling it again will lead to an extra NS_RELEASE on
// this data and a likely crash.
return NS_OK;
}
if (!mLoader->mDocument && !mIsNonDocumentSheet) {
// Sorry, we don't care about this load anymore
LOG_WARN((" No document and not non-document sheet; dropping load"));
mLoader->SheetComplete(*this, NS_BINDING_ABORTED);
return NS_OK;
}
if (NS_FAILED(aStatus)) {
LOG_WARN(
(" Load failed: status 0x%" PRIx32, static_cast<uint32_t>(aStatus)));
// Handle sheet not loading error because source was a tracking URL (or
// fingerprinting, cryptomining, etc).
// We make a note of this sheet node by including it in a dedicated
// array of blocked tracking nodes under its parent document.
//
// Multiple sheet load instances might be tied to this request,
// we annotate each one linked to a valid owning element (node).
if (net::UrlClassifierFeatureFactory::IsClassifierBlockingErrorCode(
aStatus)) {
if (Document* doc = mLoader->GetDocument()) {
for (SheetLoadData* data = this; data; data = data->mNext) {
// mOwningElement may be null but AddBlockTrackingNode can cope
nsCOMPtr<nsIContent> content =
do_QueryInterface(data->mOwningElement);
doc->AddBlockedNodeByClassifier(content);
}
}
}
mLoader->SheetComplete(*this, aStatus);
return NS_OK;
}
if (!aChannel) {
mLoader->SheetComplete(*this, NS_OK);
return NS_OK;
}
nsCOMPtr<nsIURI> originalURI;
aChannel->GetOriginalURI(getter_AddRefs(originalURI));
// If the channel's original URI is "chrome:", we want that, since
// the observer code in nsXULPrototypeCache depends on chrome stylesheets
// having a chrome URI. (Whether or not chrome stylesheets come through
// this codepath seems nondeterministic.)
// Otherwise we want the potentially-HTTP-redirected URI.
nsCOMPtr<nsIURI> channelURI;
NS_GetFinalChannelURI(aChannel, getter_AddRefs(channelURI));
if (!channelURI || !originalURI) {
NS_ERROR("Someone just violated the nsIRequest contract");
LOG_WARN((" Channel without a URI. Bad!"));
mLoader->SheetComplete(*this, NS_ERROR_UNEXPECTED);
return NS_OK;
}
nsCOMPtr<nsIPrincipal> principal;
nsIScriptSecurityManager* secMan = nsContentUtils::GetSecurityManager();
nsresult result = NS_ERROR_NOT_AVAILABLE;
if (secMan) { // Could be null if we already shut down
if (mUseSystemPrincipal) {
result = secMan->GetSystemPrincipal(getter_AddRefs(principal));
} else {
result = secMan->GetChannelResultPrincipal(aChannel,
getter_AddRefs(principal));
}
}
if (NS_FAILED(result)) {
LOG_WARN((" Couldn't get principal"));
mLoader->SheetComplete(*this, result);
return NS_OK;
}
mSheet->SetPrincipal(principal);
if (mLoaderPrincipal && mSheet->GetCORSMode() == CORS_NONE) {
bool subsumed;
result = mLoaderPrincipal->Subsumes(principal, &subsumed);
if (NS_FAILED(result) || !subsumed) {
mIsCrossOriginNoCORS = true;
}
}
// If it's an HTTP channel, we want to make sure this is not an
// error document we got.
nsCOMPtr<nsIHttpChannel> httpChannel(do_QueryInterface(aChannel));
if (httpChannel) {
bool requestSucceeded;
result = httpChannel->GetRequestSucceeded(&requestSucceeded);
if (NS_SUCCEEDED(result) && !requestSucceeded) {
LOG((" Load returned an error page"));
mLoader->SheetComplete(*this, NS_ERROR_NOT_AVAILABLE);
return NS_OK;
}
nsAutoCString sourceMapURL;
if (nsContentUtils::GetSourceMapURL(httpChannel, sourceMapURL)) {
mSheet->SetSourceMapURL(NS_ConvertUTF8toUTF16(sourceMapURL));
}
}
nsAutoCString contentType;
aChannel->GetContentType(contentType);
// In standards mode, a style sheet must have one of these MIME
// types to be processed at all. In quirks mode, we accept any
// MIME type, but only if the style sheet is same-origin with the
// requesting document or parent sheet. See bug 524223.
bool validType = contentType.EqualsLiteral("text/css") ||
contentType.EqualsLiteral(UNKNOWN_CONTENT_TYPE) ||
contentType.IsEmpty();
if (!validType) {
const char* errorMessage;
uint32_t errorFlag;
bool sameOrigin = true;
if (mLoaderPrincipal) {
bool subsumed;
result = mLoaderPrincipal->Subsumes(principal, &subsumed);
if (NS_FAILED(result) || !subsumed) {
sameOrigin = false;
}
}
if (sameOrigin && mLoader->mCompatMode == eCompatibility_NavQuirks) {
errorMessage = "MimeNotCssWarn";
errorFlag = nsIScriptError::warningFlag;
} else {
errorMessage = "MimeNotCss";
errorFlag = nsIScriptError::errorFlag;
}
AutoTArray<nsString, 2> strings;
CopyUTF8toUTF16(channelURI->GetSpecOrDefault(), *strings.AppendElement());
CopyASCIItoUTF16(contentType, *strings.AppendElement());
nsCOMPtr<nsIURI> referrer = ReferrerInfo()->GetOriginalReferrer();
nsContentUtils::ReportToConsole(
errorFlag, NS_LITERAL_CSTRING("CSS Loader"), mLoader->mDocument,
nsContentUtils::eCSS_PROPERTIES, errorMessage, strings, referrer);
if (errorFlag == nsIScriptError::errorFlag) {
LOG_WARN(
(" Ignoring sheet with improper MIME type %s", contentType.get()));
mLoader->SheetComplete(*this, NS_ERROR_NOT_AVAILABLE);
return NS_OK;
}
}
SRIMetadata sriMetadata;
mSheet->GetIntegrity(sriMetadata);
if (!sriMetadata.IsEmpty()) {
nsAutoCString sourceUri;
if (mLoader->mDocument && mLoader->mDocument->GetDocumentURI()) {
mLoader->mDocument->GetDocumentURI()->GetAsciiSpec(sourceUri);
}
nsresult rv = VerifySheetIntegrity(sriMetadata, aChannel, aBytes1, aBytes2,
sourceUri, mLoader->mReporter);
nsCOMPtr<nsILoadGroup> loadGroup;
aChannel->GetLoadGroup(getter_AddRefs(loadGroup));
if (loadGroup) {
mLoader->mReporter->FlushConsoleReports(loadGroup);
} else {
mLoader->mReporter->FlushConsoleReports(mLoader->mDocument);
}
if (NS_FAILED(rv)) {
LOG((" Load was blocked by SRI"));
MOZ_LOG(gSriPRLog, LogLevel::Debug,
("css::Loader::OnStreamComplete, bad metadata"));
mLoader->SheetComplete(*this, NS_ERROR_SRI_CORRUPT);
return NS_OK;
}
}
// Enough to set the URIs on mSheet, since any sibling datas we have share
// the same mInner as mSheet and will thus get the same URI.
mSheet->SetURIs(channelURI, originalURI, channelURI);
ReferrerPolicy policy =
nsContentUtils::GetReferrerPolicyFromChannel(aChannel);
nsCOMPtr<nsIReferrerInfo> referrerInfo =
ReferrerInfo::CreateForExternalCSSResources(mSheet, policy);
mSheet->SetReferrerInfo(referrerInfo);
return NS_OK_PARSE_SHEET;
}
Loader::IsAlternate Loader::IsAlternateSheet(const nsAString& aTitle,
bool aHasAlternateRel) {
// A sheet is alternate if it has a nonempty title that doesn't match the
// currently selected style set. But if there _is_ no currently selected
// style set, the sheet wasn't marked as an alternate explicitly, and aTitle
// is nonempty, we should select the style set corresponding to aTitle, since
// that's a preferred sheet.
if (aTitle.IsEmpty()) {
return IsAlternate::No;
}
if (mDocument) {
const nsString& currentSheetSet = mDocument->GetCurrentStyleSheetSet();
if (!aHasAlternateRel && currentSheetSet.IsEmpty()) {
// There's no preferred set yet, and we now have a sheet with a title.
// Make that be the preferred set.
// FIXME(emilio): This is kinda wild, can we do it somewhere else?
mDocument->SetPreferredStyleSheetSet(aTitle);
// We're definitely not an alternate. Also, beware that at this point
// currentSheetSet may dangle.
return IsAlternate::No;
}
if (aTitle.Equals(currentSheetSet)) {
return IsAlternate::No;
}
}
return IsAlternate::Yes;
}
nsresult Loader::CheckContentPolicy(nsIPrincipal* aLoadingPrincipal,
nsIPrincipal* aTriggeringPrincipal,
nsIURI* aTargetURI,
nsINode* aRequestingNode,
const nsAString& aNonce,
IsPreload aIsPreload) {
// When performing a system load (e.g. aUseSystemPrincipal = true)
// then aLoadingPrincipal == null; don't consult content policies.
if (!aLoadingPrincipal) {
return NS_OK;
}
nsContentPolicyType contentPolicyType =
aIsPreload == IsPreload::No
? nsIContentPolicy::TYPE_INTERNAL_STYLESHEET
: nsIContentPolicy::TYPE_INTERNAL_STYLESHEET_PRELOAD;
nsCOMPtr<nsILoadInfo> secCheckLoadInfo = new net::LoadInfo(
aLoadingPrincipal, aTriggeringPrincipal, aRequestingNode,
nsILoadInfo::SEC_ONLY_FOR_EXPLICIT_CONTENTSEC_CHECK, contentPolicyType);
// snapshot the nonce at load start time for performing CSP checks
if (contentPolicyType == nsIContentPolicy::TYPE_INTERNAL_STYLESHEET) {
secCheckLoadInfo->SetCspNonce(aNonce);
MOZ_ASSERT_IF(aIsPreload != IsPreload::No, aNonce.IsEmpty());
}
int16_t shouldLoad = nsIContentPolicy::ACCEPT;
nsresult rv = NS_CheckContentLoadPolicy(
aTargetURI, secCheckLoadInfo, NS_LITERAL_CSTRING("text/css"), &shouldLoad,
nsContentUtils::GetContentPolicy());
if (NS_FAILED(rv) || NS_CP_REJECTED(shouldLoad)) {
return NS_ERROR_CONTENT_BLOCKED;
}
return NS_OK;
}
/**
* CreateSheet() creates a StyleSheet object for the given URI.
*
* We check for an existing style sheet object for that uri in various caches
* and clone it if we find it. Cloned sheets will have the title/media/enabled
* state of the sheet they are clones off; make sure to call PrepareSheet() on
* the result of CreateSheet().
*/
Tuple<RefPtr<StyleSheet>, Loader::SheetState> Loader::CreateSheet(
nsIURI* aURI, nsIContent* aLinkingContent, nsIPrincipal* aLoaderPrincipal,
css::SheetParsingMode aParsingMode, CORSMode aCORSMode,
nsIReferrerInfo* aLoadingReferrerInfo, const nsAString& aIntegrity,
bool aSyncLoad) {
MOZ_ASSERT(aURI, "This path is not taken for inline stylesheets");
LOG(("css::Loader::CreateSheet(%s)", aURI->GetSpecOrDefault().get()));
if (!mSheets) {
mSheets = MakeUnique<Sheets>();
}
SheetLoadDataHashKey key(aURI, aLoaderPrincipal, aLoadingReferrerInfo,
aCORSMode, aParsingMode);
auto cacheResult = mSheets->Lookup(key, aSyncLoad);
if (Get<0>(cacheResult)) {
LOG((" Hit cache with state: %s",
gStateStrings[size_t(Get<1>(cacheResult))]));
return cacheResult;
}
nsIURI* sheetURI = aURI;
nsIURI* baseURI = aURI;
nsIURI* originalURI = aURI;
SRIMetadata sriMetadata;
if (!aIntegrity.IsEmpty()) {
MOZ_LOG(gSriPRLog, LogLevel::Debug,
("css::Loader::CreateSheet, integrity=%s",
NS_ConvertUTF16toUTF8(aIntegrity).get()));
nsAutoCString sourceUri;
if (mDocument && mDocument->GetDocumentURI()) {
mDocument->GetDocumentURI()->GetAsciiSpec(sourceUri);
}
SRICheck::IntegrityMetadata(aIntegrity, sourceUri, mReporter, &sriMetadata);
}
auto sheet = MakeRefPtr<StyleSheet>(aParsingMode, aCORSMode, sriMetadata);
sheet->SetURIs(sheetURI, originalURI, baseURI);
nsCOMPtr<nsIReferrerInfo> referrerInfo =
ReferrerInfo::CreateForExternalCSSResources(sheet);
sheet->SetReferrerInfo(referrerInfo);
LOG((" Needs parser"));
return MakeTuple(std::move(sheet), SheetState::NeedsParser);
}
static Loader::MediaMatched MediaListMatches(const MediaList* aMediaList,
const Document* aDocument) {
if (!aMediaList || !aDocument) {
return Loader::MediaMatched::Yes;
}
if (aMediaList->Matches(*aDocument)) {
return Loader::MediaMatched::Yes;
}
return Loader::MediaMatched::No;
}
/**
* PrepareSheet() handles setting the media and title on the sheet, as
* well as setting the enabled state based on the title and whether
* the sheet had "alternate" in its rel.
*/
Loader::MediaMatched Loader::PrepareSheet(
StyleSheet& aSheet, const nsAString& aTitle, const nsAString& aMediaString,
MediaList* aMediaList, IsAlternate aIsAlternate,
IsExplicitlyEnabled aIsExplicitlyEnabled) {
RefPtr<MediaList> mediaList(aMediaList);
if (!aMediaString.IsEmpty()) {
NS_ASSERTION(!aMediaList,
"must not provide both aMediaString and aMediaList");
mediaList = MediaList::Create(aMediaString);
}
aSheet.SetMedia(do_AddRef(mediaList));
aSheet.SetTitle(aTitle);
aSheet.SetEnabled(aIsAlternate == IsAlternate::No ||
aIsExplicitlyEnabled == IsExplicitlyEnabled::Yes);
return MediaListMatches(mediaList, mDocument);
}
/**
* InsertSheetInTree handles ordering of sheets in the document or shadow root.
*
* Here we have two types of sheets -- those with linking elements and
* those without. The latter are loaded by Link: headers, and are only added to
* the document.
*
* The following constraints are observed:
* 1) Any sheet with a linking element comes after all sheets without
* linking elements
* 2) Sheets without linking elements are inserted in the order in
* which the inserting requests come in, since all of these are
* inserted during header data processing in the content sink
* 3) Sheets with linking elements are ordered based on document order
* as determined by CompareDocumentPosition.
*/
void Loader::InsertSheetInTree(StyleSheet& aSheet,
nsIContent* aLinkingContent) {
LOG(("css::Loader::InsertSheetInTree"));
MOZ_ASSERT(mDocument, "Must have a document to insert into");
MOZ_ASSERT(!aLinkingContent || aLinkingContent->IsInUncomposedDoc() ||
aLinkingContent->IsInShadowTree(),
"Why would we insert it anywhere?");
nsCOMPtr<nsIStyleSheetLinkingElement> linkingElement =
do_QueryInterface(aLinkingContent);
if (linkingElement) {
linkingElement->SetStyleSheet(&aSheet);
}
ShadowRoot* shadow =
aLinkingContent ? aLinkingContent->GetContainingShadow() : nullptr;
auto& target = shadow ? static_cast<DocumentOrShadowRoot&>(*shadow)
: static_cast<DocumentOrShadowRoot&>(*mDocument);
// XXX Need to cancel pending sheet loads for this element, if any
int32_t sheetCount = target.SheetCount();
/*
* Start the walk at the _end_ of the list, since in the typical
* case we'll just want to append anyway. We want to break out of
* the loop when insertionPoint points to just before the index we
* want to insert at. In other words, when we leave the loop
* insertionPoint is the index of the stylesheet that immediately
* precedes the one we're inserting.
*/
int32_t insertionPoint = sheetCount - 1;
for (; insertionPoint >= 0; --insertionPoint) {
nsINode* sheetOwner = target.SheetAt(insertionPoint)->GetOwnerNode();
if (sheetOwner && !aLinkingContent) {
// Keep moving; all sheets with a sheetOwner come after all
// sheets without a linkingNode
continue;
}
if (!sheetOwner) {
// Aha! The current sheet has no sheet owner, so we want to insert after
// it no matter whether we have a linking content or not.
break;
}
MOZ_ASSERT(aLinkingContent != sheetOwner,
"Why do we still have our old sheet?");
// Have to compare
if (nsContentUtils::PositionIsBefore(sheetOwner, aLinkingContent)) {
// The current sheet comes before us, and it better be the first
// such, because now we break
break;
}
}
++insertionPoint;
if (shadow) {
shadow->InsertSheetAt(insertionPoint, aSheet);
} else {
mDocument->InsertSheetAt(insertionPoint, aSheet);
}
LOG((" Inserting into target (doc: %d) at position %d",
target.AsNode().IsDocument(), insertionPoint));
}
/**
* InsertChildSheet handles ordering of @import-ed sheet in their
* parent sheets. Here we want to just insert based on order of the
* @import rules that imported the sheets. In theory we can't just
* append to the end because the CSSOM can insert @import rules. In
* practice, we get the call to load the child sheet before the CSSOM
* has finished inserting the @import rule, so we have no idea where
* to put it anyway. So just append for now. (In the future if we
* want to insert the sheet at the correct position, we'll need to
* restore CSSStyleSheet::InsertStyleSheetAt, which was removed in
* bug 1220506.)
*/
void Loader::InsertChildSheet(StyleSheet& aSheet, StyleSheet& aParentSheet) {
LOG(("css::Loader::InsertChildSheet"));
// child sheets should always start out enabled, even if they got
// cloned off of top-level sheets which were disabled
aSheet.SetEnabled(true);
aParentSheet.AppendStyleSheet(aSheet);
LOG((" Inserting into parent sheet"));
}
/**
* LoadSheet handles the actual load of a sheet. If the load is
* supposed to be synchronous it just opens a channel synchronously
* using the given uri, wraps the resulting stream in a converter
* stream and calls ParseSheet. Otherwise it tries to look for an
* existing load for this URI and piggyback on it. Failing all that,
* a new load is kicked off asynchronously.
*/
nsresult Loader::LoadSheet(SheetLoadData& aLoadData, SheetState aSheetState,
IsPreload aIsPreload) {
LOG(("css::Loader::LoadSheet"));
MOZ_ASSERT(aLoadData.mURI, "Need a URI to load");
MOZ_ASSERT(aLoadData.mSheet, "Need a sheet to load into");
MOZ_ASSERT(aSheetState != SheetState::Complete, "Why bother?");
MOZ_ASSERT(!aLoadData.mUseSystemPrincipal || aLoadData.mSyncLoad,
"Shouldn't use system principal for async loads");
NS_ASSERTION(mSheets, "mLoadingDatas should be initialized by now.");
LOG_URI(" Load from: '%s'", aLoadData.mURI);
nsresult rv = NS_OK;
if (!mDocument && !aLoadData.mIsNonDocumentSheet) {
// No point starting the load; just release all the data and such.
LOG_WARN((" No document and not non-document sheet; pre-dropping load"));
SheetComplete(aLoadData, NS_BINDING_ABORTED);
return NS_BINDING_ABORTED;
}
SRIMetadata sriMetadata;
aLoadData.mSheet->GetIntegrity(sriMetadata);
if (aLoadData.mSyncLoad) {
LOG((" Synchronous load"));
MOZ_ASSERT(!aLoadData.mObserver, "Observer for a sync load?");
MOZ_ASSERT(aSheetState == SheetState::NeedsParser,
"Sync loads can't reuse existing async loads");
// Create a StreamLoader instance to which we will feed
// the data from the sync load. Do this before creating the
// channel to make error recovery simpler.
auto streamLoader = MakeRefPtr<StreamLoader>(aLoadData);
if (mDocument) {
net::PredictorLearn(aLoadData.mURI, mDocument->GetDocumentURI(),
nsINetworkPredictor::LEARN_LOAD_SUBRESOURCE,
mDocument);
}
nsSecurityFlags securityFlags =
nsILoadInfo::SEC_ALLOW_CROSS_ORIGIN_DATA_INHERITS |
nsILoadInfo::SEC_ALLOW_CHROME;
nsContentPolicyType contentPolicyType =
aIsPreload == IsPreload::No
? nsIContentPolicy::TYPE_INTERNAL_STYLESHEET
: nsIContentPolicy::TYPE_INTERNAL_STYLESHEET_PRELOAD;
// Just load it
nsCOMPtr<nsIChannel> channel;
// Note that we are calling NS_NewChannelWithTriggeringPrincipal() with both
// a node and a principal.
// This is because of a case where the node is the document being styled and
// the principal is the stylesheet (perhaps from a different origin) that is
// applying the styles.
if (aLoadData.mRequestingNode && aLoadData.mLoaderPrincipal) {
rv = NS_NewChannelWithTriggeringPrincipal(
getter_AddRefs(channel), aLoadData.mURI, aLoadData.mRequestingNode,
aLoadData.mLoaderPrincipal, securityFlags, contentPolicyType);
} else {
// either we are loading something inside a document, in which case
// we should always have a requestingNode, or we are loading something
// outside a document, in which case the loadingPrincipal and the
// triggeringPrincipal should always be the systemPrincipal.
auto result = URLPreloader::ReadURI(aLoadData.mURI);
if (result.isOk()) {
nsCOMPtr<nsIInputStream> stream;
MOZ_TRY(
NS_NewCStringInputStream(getter_AddRefs(stream), result.unwrap()));
rv = NS_NewInputStreamChannel(getter_AddRefs(channel), aLoadData.mURI,
stream.forget(),
nsContentUtils::GetSystemPrincipal(),
securityFlags, contentPolicyType);
} else {
rv = NS_NewChannel(getter_AddRefs(channel), aLoadData.mURI,
nsContentUtils::GetSystemPrincipal(), securityFlags,
contentPolicyType);
}
}
if (NS_FAILED(rv)) {
LOG_ERROR((" Failed to create channel"));
streamLoader->ChannelOpenFailed();
SheetComplete(aLoadData, rv);
return rv;
}
// snapshot the nonce at load start time for performing CSP checks
if (contentPolicyType == nsIContentPolicy::TYPE_INTERNAL_STYLESHEET) {
nsCOMPtr<Element> element = do_QueryInterface(aLoadData.mRequestingNode);
if (element && element->IsHTMLElement()) {
nsAutoString cspNonce;
// TODO(bug 1607009) move to SheetLoadData
element->GetAttr(nsGkAtoms::nonce, cspNonce);
nsCOMPtr<nsILoadInfo> loadInfo = channel->LoadInfo();
loadInfo->SetCspNonce(cspNonce);
}
}
nsCOMPtr<nsIInputStream> stream;
rv = channel->Open(getter_AddRefs(stream));
if (NS_FAILED(rv)) {
LOG_ERROR((" Failed to open URI synchronously"));
streamLoader->ChannelOpenFailed();
SheetComplete(aLoadData, rv);
return rv;
}
// Force UA sheets to be UTF-8.
// XXX this is only necessary because the default in
// SheetLoadData::OnDetermineCharset is wrong (bug 521039).
channel->SetContentCharset(NS_LITERAL_CSTRING("UTF-8"));
// Manually feed the streamloader the contents of the stream.
// This will call back into OnStreamComplete
// and thence to ParseSheet. Regardless of whether this fails,
// SheetComplete has been called.
return nsSyncLoadService::PushSyncStreamToListener(stream.forget(),
streamLoader, channel);
}
SheetLoadData* existingData = nullptr;
SheetLoadDataHashKey key(aLoadData);
if (aSheetState == SheetState::Loading) {
existingData = mSheets->mLoadingDatas.Get(&key);
NS_ASSERTION(existingData, "CreateSheet lied about the state");
} else if (aSheetState == SheetState::Pending) {
existingData = mSheets->mPendingDatas.GetWeak(&key);
NS_ASSERTION(existingData, "CreateSheet lied about the state");
}
if (existingData) {
LOG((" Glomming on to existing load"));
SheetLoadData* data = existingData;
while (data->mNext) {
data = data->mNext;
}
data->mNext = &aLoadData;
if (aSheetState == SheetState::Pending && !aLoadData.ShouldDefer()) {
// Kick the load off; someone cares about it right away
RefPtr<SheetLoadData> removedData;
mSheets->mPendingDatas.Remove(&key, getter_AddRefs(removedData));
MOZ_ASSERT(removedData == existingData, "Bad loading table");
LOG((" Forcing load of pending data"));
return LoadSheet(*removedData, SheetState::NeedsParser, aIsPreload);
}
// All done here; once the load completes we'll be marked complete
// automatically
return NS_OK;
}
nsCOMPtr<nsILoadGroup> loadGroup;
nsCOMPtr<nsICookieSettings> cookieSettings;
if (mDocument) {
loadGroup = mDocument->GetDocumentLoadGroup();
// load for a document with no loadgrup indicates that something is
// completely bogus, let's bail out early.
if (!loadGroup) {
LOG_ERROR((" Failed to query loadGroup from document"));
SheetComplete(aLoadData, NS_ERROR_UNEXPECTED);
return NS_ERROR_UNEXPECTED;
}
cookieSettings = mDocument->CookieSettings();
}
#ifdef DEBUG
AutoRestore<bool> syncCallbackGuard(mSyncCallback);
mSyncCallback = true;
#endif
CORSMode ourCORSMode = aLoadData.mSheet->GetCORSMode();
nsSecurityFlags securityFlags =
ourCORSMode == CORS_NONE
? nsILoadInfo::SEC_ALLOW_CROSS_ORIGIN_DATA_INHERITS
: nsILoadInfo::SEC_REQUIRE_CORS_DATA_INHERITS;
if (ourCORSMode == CORS_ANONYMOUS) {
securityFlags |= nsILoadInfo::SEC_COOKIES_SAME_ORIGIN;
} else if (ourCORSMode == CORS_USE_CREDENTIALS) {
securityFlags |= nsILoadInfo::SEC_COOKIES_INCLUDE;
}
securityFlags |= nsILoadInfo::SEC_ALLOW_CHROME;
nsContentPolicyType contentPolicyType =
aIsPreload == IsPreload::No
? nsIContentPolicy::TYPE_INTERNAL_STYLESHEET
: nsIContentPolicy::TYPE_INTERNAL_STYLESHEET_PRELOAD;
nsCOMPtr<nsIChannel> channel;
// Note we are calling NS_NewChannelWithTriggeringPrincipal here with a node
// and a principal. This is because of a case where the node is the document
// being styled and the principal is the stylesheet (perhaps from a different
// origin) that is applying the styles.
if (aLoadData.mRequestingNode && aLoadData.mLoaderPrincipal) {
rv = NS_NewChannelWithTriggeringPrincipal(
getter_AddRefs(channel), aLoadData.mURI, aLoadData.mRequestingNode,
aLoadData.mLoaderPrincipal, securityFlags, contentPolicyType,
/* PerformanceStorage */ nullptr, loadGroup);
} else {
// either we are loading something inside a document, in which case
// we should always have a requestingNode, or we are loading something
// outside a document, in which case the loadingPrincipal and the
// triggeringPrincipal should always be the systemPrincipal.
rv = NS_NewChannel(getter_AddRefs(channel), aLoadData.mURI,
nsContentUtils::GetSystemPrincipal(), securityFlags,
contentPolicyType, cookieSettings,
/* aPerformanceStorage */ nullptr, loadGroup);
}
if (NS_FAILED(rv)) {
LOG_ERROR((" Failed to create channel"));
SheetComplete(aLoadData, rv);
return rv;
}
// snapshot the nonce at load start time for performing CSP checks
if (contentPolicyType == nsIContentPolicy::TYPE_INTERNAL_STYLESHEET) {
nsCOMPtr<Element> element = do_QueryInterface(aLoadData.mRequestingNode);
if (element && element->IsHTMLElement()) {
nsAutoString cspNonce;
// TODO(bug 1607009) move to SheetLoadData
element->GetAttr(nsGkAtoms::nonce, cspNonce);
nsCOMPtr<nsILoadInfo> loadInfo = channel->LoadInfo();
loadInfo->SetCspNonce(cspNonce);
}
}
if (!aLoadData.ShouldDefer()) {
if (nsCOMPtr<nsIClassOfService> cos = do_QueryInterface(channel)) {
cos->AddClassFlags(nsIClassOfService::Leader);
}
if (aIsPreload == IsPreload::FromLink) {
if (nsCOMPtr<nsISupportsPriority> sp = do_QueryInterface(channel)) {
sp->AdjustPriority(nsISupportsPriority::PRIORITY_HIGHEST);
}
}
}
if (nsCOMPtr<nsIHttpChannel> httpChannel = do_QueryInterface(channel)) {
if (nsCOMPtr<nsIReferrerInfo> referrerInfo = aLoadData.ReferrerInfo()) {
rv = httpChannel->SetReferrerInfo(referrerInfo);
Unused << NS_WARN_IF(NS_FAILED(rv));
}
nsCOMPtr<nsIHttpChannelInternal> internalChannel =
do_QueryInterface(httpChannel);
if (internalChannel) {
rv = internalChannel->SetIntegrityMetadata(
sriMetadata.GetIntegrityString());
NS_ENSURE_SUCCESS(rv, rv);
}
// Set the initiator type
if (nsCOMPtr<nsITimedChannel> timedChannel =
do_QueryInterface(httpChannel)) {
if (aLoadData.mParentData) {
timedChannel->SetInitiatorType(NS_LITERAL_STRING("css"));
// This is a child sheet load.
//
// The resource timing of the sub-resources that a document loads
// should normally be reported to the document. One exception is any
// sub-resources of any cross-origin resources that are loaded. We
// don't mind reporting timing data for a direct child cross-origin
// resource since the resource that linked to it (and hence potentially
// anything in that parent origin) is aware that the cross-origin
// resources is to be loaded. However, we do not want to report
// timings for any sub-resources that a cross-origin resource may load
// since that obviously leaks information about what the cross-origin
// resource loads, which is bad.
//
// In addition to checking whether we're an immediate child resource of
// a cross-origin resource (by checking if mIsCrossOriginNoCORS is set
// to true on our parent), we also check our parent to see whether it
// itself is a sub-resource of a cross-origin resource by checking
// mBlockResourceTiming. If that is set then we too are such a
// sub-resource and so we set the flag on ourself too to propagate it
// on down.
//
if (aLoadData.mParentData->mIsCrossOriginNoCORS ||
aLoadData.mParentData->mBlockResourceTiming) {
// Set a flag so any other stylesheet triggered by this one will
// not be reported
aLoadData.mBlockResourceTiming = true;
// Mark the channel so PerformanceMainThread::AddEntry will not
// report the resource.
timedChannel->SetReportResourceTiming(false);
}
} else {
timedChannel->SetInitiatorType(NS_LITERAL_STRING("link"));
}
}
}
// Now tell the channel we expect text/css data back.... We do
// this before opening it, so it's only treated as a hint.
channel->SetContentType(NS_LITERAL_CSTRING("text/css"));
// We don't have to hold on to the stream loader. The ownership
// model is: Necko owns the stream loader, which owns the load data,
// which owns us
auto streamLoader = MakeRefPtr<StreamLoader>(aLoadData);
if (mDocument) {
net::PredictorLearn(aLoadData.mURI, mDocument->GetDocumentURI(),
nsINetworkPredictor::LEARN_LOAD_SUBRESOURCE, mDocument);
}
rv = channel->AsyncOpen(streamLoader);
if (NS_FAILED(rv)) {
LOG_ERROR((" Failed to create stream loader"));
streamLoader->ChannelOpenFailed();
SheetComplete(aLoadData, rv);
return rv;
}
mSheets->mLoadingDatas.Put(&key, &aLoadData);
aLoadData.mIsLoading = true;
return NS_OK;
}
/**
* ParseSheet handles parsing the data stream.
*/
Loader::Completed Loader::ParseSheet(const nsACString& aBytes,
SheetLoadData& aLoadData,
AllowAsyncParse aAllowAsync) {
LOG(("css::Loader::ParseSheet"));
AUTO_PROFILER_LABEL("css::Loader::ParseSheet", LAYOUT_CSSParsing);
aLoadData.mIsBeingParsed = true;
StyleSheet* sheet = aLoadData.mSheet;
MOZ_ASSERT(sheet);
// Some cases, like inline style and UA stylesheets, need to be parsed
// synchronously. The former may trigger child loads, the latter must not.
if (aLoadData.mSyncLoad || aAllowAsync == AllowAsyncParse::No) {
sheet->ParseSheetSync(this, aBytes, &aLoadData, aLoadData.mLineNumber);
aLoadData.mIsBeingParsed = false;
bool noPendingChildren = aLoadData.mPendingChildren == 0;
MOZ_ASSERT_IF(aLoadData.mSyncLoad, noPendingChildren);
if (noPendingChildren) {
SheetComplete(aLoadData, NS_OK);
return Completed::Yes;
}
return Completed::No;
}
// This parse does not need to be synchronous. \o/
//
// Note that we need to block onload because there may be no network requests
// pending.
BlockOnload();
nsCOMPtr<nsISerialEventTarget> target = DispatchTarget();
sheet->ParseSheet(*this, aBytes, aLoadData)
->Then(
target, __func__,
[loadData = RefPtr<SheetLoadData>(&aLoadData)](bool aDummy) {
MOZ_ASSERT(NS_IsMainThread());
loadData->mLoader->UnblockOnload(/* aFireSync = */ false);
loadData->SheetFinishedParsingAsync();
},
[] { MOZ_CRASH("rejected parse promise"); });
return Completed::No;
}
/**
* SheetComplete is the do-it-all cleanup function. It removes the
* load data from the "loading" hashtable, adds the sheet to the
* "completed" hashtable, massages the XUL cache, handles siblings of
* the load data (other loads for the same URI), handles unblocking
* blocked parent loads as needed, and most importantly calls
* NS_RELEASE on the load data to destroy the whole mess.
*/
void Loader::SheetComplete(SheetLoadData& aLoadData, nsresult aStatus) {
LOG(("css::Loader::SheetComplete, status: 0x%" PRIx32,
static_cast<uint32_t>(aStatus)));
// If aStatus is a failure we need to mark this data failed. We also need to
// mark any ancestors of a failing data as failed and any sibling of a
// failing data as failed. Note that SheetComplete is never called on a
// SheetLoadData that is the mNext of some other SheetLoadData.
if (NS_FAILED(aStatus)) {
MarkLoadTreeFailed(aLoadData);
}
if (mDocument) {
mDocument->MaybeWarnAboutZoom();
}
// 8 is probably big enough for all our common cases. It's not likely that
// imports will nest more than 8 deep, and multiple sheets with the same URI
// are rare.
AutoTArray<RefPtr<SheetLoadData>, 8> datasToNotify;
DoSheetComplete(aLoadData, datasToNotify);
// Now it's safe to go ahead and notify observers
uint32_t count = datasToNotify.Length();
mDatasToNotifyOn += count;
for (RefPtr<SheetLoadData>& data : datasToNotify) {
--mDatasToNotifyOn;
MOZ_ASSERT(data, "How did this data get here?");
if (data->mObserver) {
LOG((" Notifying observer %p for data %p. deferred: %d",
data->mObserver.get(), data.get(), data->ShouldDefer()));
data->mObserver->StyleSheetLoaded(data->mSheet, data->ShouldDefer(),
aStatus);
}
nsTObserverArray<nsCOMPtr<nsICSSLoaderObserver>>::ForwardIterator iter(
mObservers);
nsCOMPtr<nsICSSLoaderObserver> obs;
while (iter.HasMore()) {
obs = iter.GetNext();
LOG((" Notifying global observer %p for data %p. deferred: %d",
obs.get(), data.get(), data->ShouldDefer()));
obs->StyleSheetLoaded(data->mSheet, data->ShouldDefer(), aStatus);
}
}
if (mSheets && mSheets->mLoadingDatas.Count() == 0 &&
mSheets->mPendingDatas.Count() > 0) {
LOG((" No more loading sheets; starting deferred loads"));
StartDeferredLoads();
}
}
void Loader::DoSheetComplete(SheetLoadData& aLoadData,
LoadDataArray& aDatasToNotify) {
LOG(("css::Loader::DoSheetComplete"));
MOZ_ASSERT(aLoadData.mSheet, "Must have a sheet");
NS_ASSERTION(mSheets || !aLoadData.mURI || aLoadData.mSheet->IsConstructed(),
"mLoadingDatas should be initialized by now.");
// Twiddle the hashtables
if (aLoadData.mURI) {
LOG_URI(" Finished loading: '%s'", aLoadData.mURI);
// Remove the data from the list of loading datas
if (aLoadData.mIsLoading) {
SheetLoadDataHashKey key(aLoadData);
Maybe<SheetLoadData*> loadingData =
mSheets->mLoadingDatas.GetAndRemove(&key);
MOZ_DIAGNOSTIC_ASSERT(loadingData && loadingData.value() == &aLoadData);
Unused << loadingData;
aLoadData.mIsLoading = false;
}
}
// Go through and deal with the whole linked list.
SheetLoadData* data = &aLoadData;
do {
MOZ_DIAGNOSTIC_ASSERT(!data->mSheetCompleteCalled);
#ifdef MOZ_DIAGNOSTIC_ASSERT_ENABLED
data->mSheetCompleteCalled = true;
#endif
if (!data->mSheetAlreadyComplete) {
// If mSheetAlreadyComplete, then the sheet could well be modified between
// when we posted the async call to SheetComplete and now, since the sheet
// was page-accessible during that whole time.
// HasForcedUniqueInner() is okay if the sheet is constructed, because
// constructed sheets are always unique and they may be set to complete
// multiple times if their rules are replaced via Replace()
MOZ_ASSERT(data->mSheet->IsConstructed() ||
!data->mSheet->HasForcedUniqueInner(),
"should not get a forced unique inner during parsing");
data->mSheet->SetComplete();
data->ScheduleLoadEventIfNeeded();
}
if (data->mMustNotify && (data->mObserver || !mObservers.IsEmpty())) {
// Don't notify here so we don't trigger script. Remember the
// info we need to notify, then do it later when it's safe.
aDatasToNotify.AppendElement(data);
// On append failure, just press on. We'll fail to notify the observer,
// but not much we can do about that....
}
NS_ASSERTION(!data->mParentData || data->mParentData->mPendingChildren != 0,
"Broken pending child count on our parent");
// If we have a parent, our parent is no longer being parsed, and
// we are the last pending child, then our load completion
// completes the parent too. Note that the parent _can_ still be
// being parsed (eg if the child (us) failed to open the channel
// or some such).
if (data->mParentData && --(data->mParentData->mPendingChildren) == 0 &&
!data->mParentData->mIsBeingParsed) {
DoSheetComplete(*data->mParentData, aDatasToNotify);
}
data = data->mNext;
} while (data);
// Now that it's marked complete, put the sheet in our cache.
// If we ever start doing this for failed loads, we'll need to
// adjust the PostLoadEvent code that thinks anything already
// complete must have loaded succesfully.
// We don't want to use mSheets for constructable stylesheets.
if (!aLoadData.mLoadFailed && aLoadData.mURI &&
!aLoadData.mSheet->IsConstructed()) {
// Pick our sheet to cache carefully. Ideally, we want to cache
// one of the sheets that will be kept alive by a document or
// parent sheet anyway, so that if someone then accesses it via
// CSSOM we won't have extra clones of the inner lying around.
data = &aLoadData;
StyleSheet* sheet = aLoadData.mSheet;
do {
if (data->mSheet->GetParentSheet() || data->mSheet->GetOwnerNode()) {
sheet = data->mSheet;
break;
}
data = data->mNext;
} while (data);
#ifdef MOZ_XUL
if (IsChromeURI(aLoadData.mURI)) {
nsXULPrototypeCache* cache = nsXULPrototypeCache::GetInstance();
if (cache && cache->IsEnabled()) {
if (!cache->GetStyleSheet(aLoadData.mURI)) {
LOG((" Putting sheet in XUL prototype cache"));
NS_ASSERTION(sheet->IsComplete(),
"Should only be caching complete sheets");
cache->PutStyleSheet(sheet);
}
}
} else {
#endif
SheetLoadDataHashKey key(aLoadData);
NS_ASSERTION(sheet->IsComplete(),
"Should only be caching complete sheets");
mSheets->mCompleteSheets.Put(&key, RefPtr{sheet});
#ifdef MOZ_XUL
}
#endif
}
}
void Loader::MarkLoadTreeFailed(SheetLoadData& aLoadData) {
if (aLoadData.mURI) {
LOG_URI(" Load failed: '%s'", aLoadData.mURI);
}
SheetLoadData* data = &aLoadData;
do {
data->mLoadFailed = true;
data->mSheet->MaybeRejectReplacePromise();
if (data->mParentData) {
MarkLoadTreeFailed(*data->mParentData);
}
data = data->mNext;
} while (data);
}
Result<Loader::LoadSheetResult, nsresult> Loader::LoadInlineStyle(
const SheetInfo& aInfo, const nsAString& aBuffer, uint32_t aLineNumber,
nsICSSLoaderObserver* aObserver) {
LOG(("css::Loader::LoadInlineStyle"));
if (!mEnabled) {
LOG_WARN((" Not enabled"));
return Err(NS_ERROR_NOT_AVAILABLE);
}
if (!mDocument) {
return Err(NS_ERROR_NOT_INITIALIZED);
}
nsCOMPtr<nsIStyleSheetLinkingElement> owningElement(
do_QueryInterface(aInfo.mContent));
NS_ASSERTION(owningElement, "Element is not a style linking element!");
// Since we're not planning to load a URI, no need to hand a principal to the
// load data or to CreateSheet().
// Check IsAlternateSheet now, since it can mutate our document.
auto isAlternate = IsAlternateSheet(aInfo.mTitle, aInfo.mHasAlternateRel);
LOG((" Sheet is alternate: %d", static_cast<int>(isAlternate)));
// Use the document's base URL so that @import in the inline sheet picks up
// the right base.
nsIURI* baseURI = aInfo.mContent->GetBaseURI();
nsIURI* sheetURI = aInfo.mContent->OwnerDoc()->GetDocumentURI();
nsIURI* originalURI = nullptr;
MOZ_ASSERT(aInfo.mIntegrity.IsEmpty());
// We only cache sheets if in shadow trees, since regular document sheets are
// likely to be unique.
const bool isWorthCaching = aInfo.mContent->IsInShadowTree();
RefPtr<StyleSheet> sheet;
if (isWorthCaching) {
if (!mSheets) {
mSheets = MakeUnique<Sheets>();
}
sheet = mSheets->LookupInline(aBuffer);
}
const bool sheetFromCache = !!sheet;
if (!sheet) {
sheet = MakeRefPtr<StyleSheet>(eAuthorSheetFeatures, aInfo.mCORSMode,
SRIMetadata{});
sheet->SetURIs(sheetURI, originalURI, baseURI);
nsCOMPtr<nsIReferrerInfo> referrerInfo =
ReferrerInfo::CreateForInternalCSSResources(aInfo.mContent->OwnerDoc());
sheet->SetReferrerInfo(referrerInfo);
nsIPrincipal* principal = aInfo.mContent->NodePrincipal();
if (aInfo.mTriggeringPrincipal) {
// The triggering principal may be an expanded principal, which is safe to
// use for URL security checks, but not as the loader principal for a
// stylesheet. So treat this as principal inheritance, and downgrade if
// necessary.
principal =
BasePrincipal::Cast(aInfo.mTriggeringPrincipal)->PrincipalToInherit();
}
// We never actually load this, so just set its principal directly
sheet->SetPrincipal(principal);
}
auto matched = PrepareSheet(*sheet, aInfo.mTitle, aInfo.mMedia, nullptr,
isAlternate, aInfo.mIsExplicitlyEnabled);
InsertSheetInTree(*sheet, aInfo.mContent);
Completed completed;
if (sheetFromCache) {
MOZ_ASSERT(sheet->IsComplete());
completed = Completed::Yes;
} else {
auto data = MakeRefPtr<SheetLoadData>(
this, aInfo.mTitle, nullptr, sheet, false, owningElement, isAlternate,
matched, aObserver, nullptr, aInfo.mReferrerInfo, aInfo.mContent);
data->mLineNumber = aLineNumber;
// Parse completion releases the load data.
//
// Note that we need to parse synchronously, since the web expects that the
// effects of inline stylesheets are visible immediately (aside from
// @imports).
NS_ConvertUTF16toUTF8 utf8(aBuffer);
completed = ParseSheet(utf8, *data, AllowAsyncParse::No);
if (completed == Completed::Yes) {
// TODO(emilio): Try to cache sheets with @import rules, maybe?
if (isWorthCaching) {
mSheets->mInlineSheets.Put(aBuffer, std::move(sheet));
}
} else {
data->mMustNotify = true;
}
}
return LoadSheetResult{completed, isAlternate, matched};
}
Result<Loader::LoadSheetResult, nsresult> Loader::LoadStyleLink(
const SheetInfo& aInfo, nsICSSLoaderObserver* aObserver) {
MOZ_ASSERT(aInfo.mURI, "Must have URL to load");
LOG(("css::Loader::LoadStyleLink"));
LOG_URI(" Link uri: '%s'", aInfo.mURI);
LOG((" Link title: '%s'", NS_ConvertUTF16toUTF8(aInfo.mTitle).get()));
LOG((" Link media: '%s'", NS_ConvertUTF16toUTF8(aInfo.mMedia).get()));
LOG((" Link alternate rel: %d", aInfo.mHasAlternateRel));
if (!mEnabled) {
LOG_WARN((" Not enabled"));
return Err(NS_ERROR_NOT_AVAILABLE);
}
if (!mDocument) {
return Err(NS_ERROR_NOT_INITIALIZED);
}
nsIPrincipal* loadingPrincipal = aInfo.mContent
? aInfo.mContent->NodePrincipal()
: mDocument->NodePrincipal();
nsIPrincipal* principal = aInfo.mTriggeringPrincipal
? aInfo.mTriggeringPrincipal.get()
: loadingPrincipal;
nsINode* context = aInfo.mContent;
if (!context) {
context = mDocument;
}
bool syncLoad = aInfo.mContent && aInfo.mContent->IsInUAWidget() &&
IsChromeURI(aInfo.mURI);
LOG((" Link sync load: '%s'", syncLoad ? "true" : "false"));
MOZ_ASSERT_IF(syncLoad, !aObserver);
nsresult rv = CheckContentPolicy(loadingPrincipal, principal, aInfo.mURI,
context, aInfo.mNonce, IsPreload::No);
if (NS_WARN_IF(NS_FAILED(rv))) {
// Don't fire the error event if our document is loaded as data. We're
// supposed to not even try to do loads in that case... Unfortunately, we
// implement that via nsDataDocumentContentPolicy, which doesn't have a good
// way to communicate back to us that _it_ is the thing that blocked the
// load.
if (aInfo.mContent && !mDocument->IsLoadedAsData()) {
// Fire an async error event on it.
RefPtr<AsyncEventDispatcher> loadBlockingAsyncDispatcher =
new LoadBlockingAsyncEventDispatcher(
aInfo.mContent, NS_LITERAL_STRING("error"), CanBubble::eNo,
ChromeOnlyDispatch::eNo);
loadBlockingAsyncDispatcher->PostDOMEvent();
}
return Err(rv);
}
// Check IsAlternateSheet now, since it can mutate our document and make
// pending sheets go to the non-pending state.
auto isAlternate = IsAlternateSheet(aInfo.mTitle, aInfo.mHasAlternateRel);
SheetState state;
RefPtr<StyleSheet> sheet;
Tie(sheet, state) =
CreateSheet(aInfo, principal, eAuthorSheetFeatures, syncLoad);
LOG((" Sheet is alternate: %d", static_cast<int>(isAlternate)));
auto matched = PrepareSheet(*sheet, aInfo.mTitle, aInfo.mMedia, nullptr,
isAlternate, aInfo.mIsExplicitlyEnabled);
InsertSheetInTree(*sheet, aInfo.mContent);
nsCOMPtr<nsIStyleSheetLinkingElement> owningElement(
do_QueryInterface(aInfo.mContent));
if (state == SheetState::Complete) {
LOG((" Sheet already complete: 0x%p", sheet.get()));
if (aObserver || !mObservers.IsEmpty() || owningElement) {
rv = PostLoadEvent(aInfo.mURI, sheet, aObserver, isAlternate, matched,
aInfo.mReferrerInfo, owningElement);
if (NS_FAILED(rv)) {
return Err(rv);
}
}
// The load hasn't been completed yet, will be done in PostLoadEvent.
return LoadSheetResult{Completed::No, isAlternate, matched};
}
// Now we need to actually load it.
auto data = MakeRefPtr<SheetLoadData>(
this, aInfo.mTitle, aInfo.mURI, sheet, syncLoad, owningElement,
isAlternate, matched, aObserver, principal, aInfo.mReferrerInfo, context);
auto result = LoadSheetResult{Completed::No, isAlternate, matched};
MOZ_ASSERT(result.ShouldBlock() == !data->ShouldDefer(),
"These should better match!");
// If we have to parse and it's a non-blocking non-inline sheet, defer it.
if (!syncLoad && state == SheetState::NeedsParser &&
mSheets->mLoadingDatas.Count() != 0 && !result.ShouldBlock()) {
LOG((" Deferring sheet load"));
SheetLoadDataHashKey key(*data);
mSheets->mPendingDatas.Put(&key, RefPtr{data});
data->mMustNotify = true;
return result;
}
// Load completion will free the data
rv = LoadSheet(*data, state, IsPreload::No);
if (NS_FAILED(rv)) {
return Err(rv);
}
if (!syncLoad) {
data->mMustNotify = true;
}
return result;
}
static bool HaveAncestorDataWithURI(SheetLoadData& aData, nsIURI* aURI) {
if (!aData.mURI) {
// Inline style; this won't have any ancestors
MOZ_ASSERT(!aData.mParentData, "How does inline style have a parent?");
return false;
}
bool equal;
if (NS_FAILED(aData.mURI->Equals(aURI, &equal)) || equal) {
return true;
}
// Datas down the mNext chain have the same URI as aData, so we
// don't have to compare to them. But they might have different
// parents, and we have to check all of those.
SheetLoadData* data = &aData;
do {
if (data->mParentData &&
HaveAncestorDataWithURI(*data->mParentData, aURI)) {
return true;
}
data = data->mNext;
} while (data);
return false;
}
nsresult Loader::LoadChildSheet(StyleSheet& aParentSheet,
SheetLoadData* aParentData, nsIURI* aURL,
dom::MediaList* aMedia,
LoaderReusableStyleSheets* aReusableSheets) {
LOG(("css::Loader::LoadChildSheet"));
MOZ_ASSERT(aURL, "Must have a URI to load");
if (!mEnabled) {
LOG_WARN((" Not enabled"));
return NS_ERROR_NOT_AVAILABLE;
}
LOG_URI(" Child uri: '%s'", aURL);
nsCOMPtr<nsINode> owningNode;
// Check for an associated document or shadow root: if none, don't bother
// walking up the parent sheets.
if (aParentSheet.GetAssociatedDocumentOrShadowRoot()) {
StyleSheet* topSheet = &aParentSheet;
while (StyleSheet* parent = topSheet->GetParentSheet()) {
topSheet = parent;
}
owningNode = topSheet->GetOwnerNode();
}
nsINode* context = nullptr;
nsIPrincipal* loadingPrincipal = nullptr;
if (owningNode) {
context = owningNode;
loadingPrincipal = owningNode->NodePrincipal();
} else if (mDocument) {
context = mDocument;
loadingPrincipal = mDocument->NodePrincipal();
}
nsIPrincipal* principal = aParentSheet.Principal();
nsresult rv = CheckContentPolicy(loadingPrincipal, principal, aURL, context,
EmptyString(), IsPreload::No);
if (NS_WARN_IF(NS_FAILED(rv))) {
if (aParentData) {
MarkLoadTreeFailed(*aParentData);
}
return rv;
}
nsCOMPtr<nsICSSLoaderObserver> observer;
if (aParentData) {
LOG((" Have a parent load"));
// Check for cycles
if (HaveAncestorDataWithURI(*aParentData, aURL)) {
// Houston, we have a loop, blow off this child and pretend this never
// happened
LOG_ERROR((" @import cycle detected, dropping load"));
return NS_OK;
}
NS_ASSERTION(aParentData->mSheet == &aParentSheet,
"Unexpected call to LoadChildSheet");
} else {
LOG((" No parent load; must be CSSOM"));
// No parent load data, so the sheet will need to be notified when
// we finish, if it can be, if we do the load asynchronously.
observer = &aParentSheet;
}
// Now that we know it's safe to load this (passes security check and not a
// loop) do so.
RefPtr<StyleSheet> sheet;
SheetState state;
if (aReusableSheets && aReusableSheets->FindReusableStyleSheet(aURL, sheet)) {
state = SheetState::Complete;
} else {
// For now, use CORS_NONE for child sheets
Tie(sheet, state) =
CreateSheet(aURL, nullptr, principal, aParentSheet.ParsingMode(),
CORS_NONE, aParentSheet.GetReferrerInfo(),
EmptyString(), // integrity is only checked on main sheet
aParentData ? aParentData->mSyncLoad : false);
PrepareSheet(*sheet, EmptyString(), EmptyString(), aMedia, IsAlternate::No,
IsExplicitlyEnabled::No);
}
MOZ_ASSERT(sheet);
InsertChildSheet(*sheet, aParentSheet);
if (state == SheetState::Complete) {
LOG((" Sheet already complete"));
// We're completely done. No need to notify, even, since the
// @import rule addition/modification will trigger the right style
// changes automatically.
return NS_OK;
}
auto data = MakeRefPtr<SheetLoadData>(
this, aURL, sheet, aParentData, observer, principal,
aParentSheet.GetReferrerInfo(), context);
bool syncLoad = data->mSyncLoad;
// Load completion will release the data
rv = LoadSheet(*data, state, IsPreload::No);
NS_ENSURE_SUCCESS(rv, rv);
if (!syncLoad) {
data->mMustNotify = true;
}
return rv;
}
Result<RefPtr<StyleSheet>, nsresult> Loader::LoadSheetSync(
nsIURI* aURL, SheetParsingMode aParsingMode,
UseSystemPrincipal aUseSystemPrincipal) {
LOG(("css::Loader::LoadSheetSync"));
nsCOMPtr<nsIReferrerInfo> referrerInfo = new ReferrerInfo(nullptr);
return InternalLoadNonDocumentSheet(
aURL, IsPreload::No, aParsingMode, aUseSystemPrincipal, nullptr, nullptr,
referrerInfo, nullptr, CORS_NONE, EmptyString());
}
Result<RefPtr<StyleSheet>, nsresult> Loader::LoadSheet(
nsIURI* aURI, SheetParsingMode aParsingMode,
UseSystemPrincipal aUseSystemPrincipal, nsICSSLoaderObserver* aObserver) {
nsCOMPtr<nsIReferrerInfo> referrerInfo = new ReferrerInfo(nullptr);
return InternalLoadNonDocumentSheet(
aURI, IsPreload::No, aParsingMode, aUseSystemPrincipal, nullptr, nullptr,
referrerInfo, aObserver, CORS_NONE, EmptyString());
}
Result<RefPtr<StyleSheet>, nsresult> Loader::LoadSheet(
nsIURI* aURL, IsPreload aIsPreload, nsIPrincipal* aOriginPrincipal,
const Encoding* aPreloadEncoding, nsIReferrerInfo* aReferrerInfo,
nsICSSLoaderObserver* aObserver, CORSMode aCORSMode,
const nsAString& aIntegrity) {
LOG(("css::Loader::LoadSheet(aURL, aObserver) api call"));
return InternalLoadNonDocumentSheet(aURL, aIsPreload, eAuthorSheetFeatures,
UseSystemPrincipal::No, aOriginPrincipal,
aPreloadEncoding, aReferrerInfo,
aObserver, aCORSMode, aIntegrity);
}
Result<RefPtr<StyleSheet>, nsresult> Loader::InternalLoadNonDocumentSheet(
nsIURI* aURL, IsPreload aIsPreload, SheetParsingMode aParsingMode,
UseSystemPrincipal aUseSystemPrincipal, nsIPrincipal* aOriginPrincipal,
const Encoding* aPreloadEncoding, nsIReferrerInfo* aReferrerInfo,
nsICSSLoaderObserver* aObserver, CORSMode aCORSMode,
const nsAString& aIntegrity) {
MOZ_ASSERT(aURL, "Must have a URI to load");
MOZ_ASSERT(aUseSystemPrincipal == UseSystemPrincipal::No || !aObserver,
"Shouldn't load system-principal sheets async");
MOZ_ASSERT(aReferrerInfo, "Must have referrerInfo");
LOG_URI(" Non-document sheet uri: '%s'", aURL);
if (!mEnabled) {
LOG_WARN((" Not enabled"));
return Err(NS_ERROR_NOT_AVAILABLE);
}
nsCOMPtr<nsIPrincipal> loadingPrincipal =
(aOriginPrincipal && mDocument ? mDocument->NodePrincipal() : nullptr);
nsresult rv = CheckContentPolicy(loadingPrincipal, aOriginPrincipal, aURL,
mDocument, EmptyString(), aIsPreload);
if (NS_FAILED(rv)) {
return Err(rv);
}
bool syncLoad = !aObserver;
SheetState state;
RefPtr<StyleSheet> sheet;
Tie(sheet, state) =
CreateSheet(aURL, nullptr, aOriginPrincipal, aParsingMode, aCORSMode,
aReferrerInfo, aIntegrity, syncLoad);
PrepareSheet(*sheet, EmptyString(), EmptyString(), nullptr, IsAlternate::No,
IsExplicitlyEnabled::No);
if (state == SheetState::Complete) {
LOG((" Sheet already complete"));
if (aObserver || !mObservers.IsEmpty()) {
rv = PostLoadEvent(aURL, sheet, aObserver, IsAlternate::No,
MediaMatched::Yes, aReferrerInfo, nullptr);
if (NS_FAILED(rv)) {
return Err(rv);
}
}
return sheet;
}
auto data = MakeRefPtr<SheetLoadData>(
this, aURL, sheet, syncLoad,
aUseSystemPrincipal == UseSystemPrincipal::Yes, aPreloadEncoding,
aObserver, aOriginPrincipal, aReferrerInfo, mDocument);
rv = LoadSheet(*data, state, aIsPreload);
if (NS_FAILED(rv)) {
return Err(rv);
}
if (aObserver) {
data->mMustNotify = true;
}
return sheet;
}
nsresult Loader::PostLoadEvent(nsIURI* aURI, StyleSheet* aSheet,
nsICSSLoaderObserver* aObserver,
IsAlternate aWasAlternate,
MediaMatched aMediaMatched,
nsIReferrerInfo* aReferrerInfo,
nsIStyleSheetLinkingElement* aElement) {
LOG(("css::Loader::PostLoadEvent"));
MOZ_ASSERT(aSheet, "Must have sheet");
MOZ_ASSERT(aObserver || !mObservers.IsEmpty() || aElement,
"Must have observer or element");
RefPtr<SheetLoadData> evt = new SheetLoadData(
this,
EmptyString(), // title doesn't matter here
aURI, aSheet, false, aElement, aWasAlternate, aMediaMatched, aObserver,
nullptr, aReferrerInfo, mDocument);
mPostedEvents.AppendElement(evt);
nsresult rv;
RefPtr<SheetLoadData> runnable(evt);
if (mDocument) {
rv = mDocument->Dispatch(TaskCategory::Other, runnable.forget());
} else if (mDocGroup) {
rv = mDocGroup->Dispatch(TaskCategory::Other, runnable.forget());
} else {
rv = SystemGroup::Dispatch(TaskCategory::Other, runnable.forget());
}
if (NS_FAILED(rv)) {
NS_WARNING("failed to dispatch stylesheet load event");
mPostedEvents.RemoveElement(evt);
} else {
// We'll unblock onload when we handle the event.
BlockOnload();
// We want to notify the observer for this data.
evt->mMustNotify = true;
evt->mSheetAlreadyComplete = true;
// If we get to this code, aSheet loaded correctly at some point, so
// we can just schedule a load event and don't need to touch the
// data's mLoadFailed. Note that we do this here and not from
// inside our SheetComplete so that we don't end up running the load
// event async.
MOZ_ASSERT(!evt->mLoadFailed, "Why are we marked as failed?");
evt->ScheduleLoadEventIfNeeded();
}
return rv;
}
void Loader::HandleLoadEvent(SheetLoadData& aEvent) {
// XXXbz can't assert this yet.... May not have an observer because
// we're unblocking the parser
// NS_ASSERTION(aEvent->mObserver, "Must have observer");
NS_ASSERTION(aEvent.mSheet, "Must have sheet");
// Very important: this needs to come before the SheetComplete call
// below, so that HasPendingLoads() will test true as needed under
// notifications we send from that SheetComplete call.
mPostedEvents.RemoveElement(&aEvent);
if (!aEvent.mIsCancelled) {
SheetComplete(aEvent, NS_OK);
}
UnblockOnload(true);
}
void Loader::Stop() {
uint32_t pendingCount = mSheets ? mSheets->mPendingDatas.Count() : 0;
uint32_t loadingCount = mSheets ? mSheets->mLoadingDatas.Count() : 0;
LoadDataArray arr(pendingCount + loadingCount + mPostedEvents.Length());
if (pendingCount) {
for (auto iter = mSheets->mPendingDatas.Iter(); !iter.Done(); iter.Next()) {
RefPtr<SheetLoadData>& data = iter.Data();
data->mIsLoading = false; // we will handle the removal right here
data->mIsCancelled = true;
arr.AppendElement(std::move(data));
}
mSheets->mPendingDatas.Clear();
}
if (loadingCount) {
for (auto iter = mSheets->mLoadingDatas.Iter(); !iter.Done(); iter.Next()) {
SheetLoadData* data = iter.Data();
data->mIsLoading = false; // we will handle the removal right here
data->mIsCancelled = true;
arr.AppendElement(data);
}
mSheets->mLoadingDatas.Clear();
}
for (RefPtr<SheetLoadData>& data : mPostedEvents) {
data->mIsCancelled = true;
// Move since we're about to get rid of the array below.
arr.AppendElement(std::move(data));
}
mPostedEvents.Clear();
mDatasToNotifyOn += arr.Length();
for (RefPtr<SheetLoadData>& data : arr) {
--mDatasToNotifyOn;
SheetComplete(*data, NS_BINDING_ABORTED);
}
}
bool Loader::HasPendingLoads() {
return (mSheets && mSheets->mLoadingDatas.Count() != 0) ||
(mSheets && mSheets->mPendingDatas.Count() != 0) ||
mPostedEvents.Length() != 0 || mDatasToNotifyOn != 0;
}
void Loader::AddObserver(nsICSSLoaderObserver* aObserver) {
MOZ_ASSERT(aObserver, "Must have observer");
mObservers.AppendElementUnlessExists(aObserver);
}
void Loader::RemoveObserver(nsICSSLoaderObserver* aObserver) {
mObservers.RemoveElement(aObserver);
}
void Loader::StartDeferredLoads() {
MOZ_ASSERT(mSheets, "Don't call me!");
LoadDataArray arr(mSheets->mPendingDatas.Count());
for (auto iter = mSheets->mPendingDatas.Iter(); !iter.Done(); iter.Next()) {
arr.AppendElement(iter.Data());
iter.Remove();
}
mDatasToNotifyOn += arr.Length();
for (RefPtr<SheetLoadData>& data : arr) {
--mDatasToNotifyOn;
LoadSheet(*data, SheetState::NeedsParser, IsPreload::No);
}
}
NS_IMPL_CYCLE_COLLECTION_CLASS(Loader)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(Loader)
if (tmp->mSheets) {
for (auto iter = tmp->mSheets->mCompleteSheets.Iter(); !iter.Done();
iter.Next()) {
NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "OOL sheet cache in Loader");
cb.NoteXPCOMChild(iter.UserData());
}
for (auto iter = tmp->mSheets->mInlineSheets.Iter(); !iter.Done();
iter.Next()) {
NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "Inline sheet cache in Loader");
cb.NoteXPCOMChild(iter.UserData());
}
}
nsTObserverArray<nsCOMPtr<nsICSSLoaderObserver>>::ForwardIterator it(
tmp->mObservers);
while (it.HasMore()) {
ImplCycleCollectionTraverse(cb, it.GetNext(),
"mozilla::css::Loader.mObservers");
}
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(Loader)
if (tmp->mSheets) {
tmp->mSheets->mCompleteSheets.Clear();
tmp->mSheets->mInlineSheets.Clear();
}
tmp->mObservers.Clear();
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(Loader, AddRef)
NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(Loader, Release)
size_t Loader::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const {
size_t n = aMallocSizeOf(this);
if (mSheets) {
n += mSheets->SizeOfIncludingThis(aMallocSizeOf);
}
n += mObservers.ShallowSizeOfExcludingThis(aMallocSizeOf);
// Measurement of the following members may be added later if DMD finds it is
// worthwhile:
// - mPostedEvents: transient, and should be small
//
// The following members aren't measured:
// - mDocument, because it's a weak backpointer
return n;
}
void Loader::BlockOnload() {
if (mDocument) {
mDocument->BlockOnload();
}
}
void Loader::UnblockOnload(bool aFireSync) {
if (mDocument) {
mDocument->UnblockOnload(aFireSync);
}
}
already_AddRefed<nsISerialEventTarget> Loader::DispatchTarget() {
nsCOMPtr<nsISerialEventTarget> target;
if (mDocument) {
// If you change this, you may want to change StyleSheet::Replace
target = mDocument->EventTargetFor(TaskCategory::Other);
} else if (mDocGroup) {
target = mDocGroup->EventTargetFor(TaskCategory::Other);
} else {
target = SystemGroup::EventTargetFor(TaskCategory::Other);
}
return target.forget();
}
} // namespace css
} // namespace mozilla