mozilla-central/parser/html/nsHtml5StreamParser.cpp (file symbol)

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set sw=2 ts=2 et 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/. */
#include "nsHtml5StreamParser.h"
#include <stdlib.h>
#include <string.h>
#include <utility>
#include "ErrorList.h"
#include "GeckoProfiler.h"
#include "js/GCAPI.h"
#include "mozilla/Buffer.h"
#include "mozilla/CheckedInt.h"
#include "mozilla/Encoding.h"
#include "mozilla/EncodingDetector.h"
#include "mozilla/Likely.h"
#include "mozilla/Maybe.h"
#include "mozilla/SchedulerGroup.h"
#include "mozilla/ScopeExit.h"
#include "mozilla/Services.h"
#include "mozilla/StaticPrefs_html5.h"
#include "mozilla/StaticPrefs_network.h"
#include "mozilla/TextUtils.h"
#include "mozilla/glean/GleanMetrics.h"
#include "mozilla/Unused.h"
#include "mozilla/dom/BindingDeclarations.h"
#include "mozilla/dom/BrowsingContext.h"
#include "mozilla/dom/DebuggerUtilsBinding.h"
#include "mozilla/dom/Document.h"
#include "mozilla/Vector.h"
#include "nsContentSink.h"
#include "nsContentUtils.h"
#include "nsCycleCollectionTraversalCallback.h"
#include "nsHtml5AtomTable.h"
#include "nsHtml5Highlighter.h"
#include "nsHtml5Module.h"
#include "nsHtml5OwningUTF16Buffer.h"
#include "nsHtml5Parser.h"
#include "nsHtml5Speculation.h"
#include "nsHtml5StreamParserPtr.h"
#include "nsHtml5Tokenizer.h"
#include "nsHtml5TreeBuilder.h"
#include "nsHtml5TreeOpExecutor.h"
#include "nsIChannel.h"
#include "nsIContentSink.h"
#include "nsID.h"
#include "nsIDTD.h"
#include "nsIDocShell.h"
#include "nsIHttpChannel.h"
#include "nsIInputStream.h"
#include "nsINestedURI.h"
#include "nsIObserverService.h"
#include "nsIRequest.h"
#include "nsIRunnable.h"
#include "nsIScriptError.h"
#include "nsIThread.h"
#include "nsIThreadRetargetableRequest.h"
#include "nsITimer.h"
#include "nsIURI.h"
#include "nsJSEnvironment.h"
#include "nsLiteralString.h"
#include "nsNetUtil.h"
#include "nsString.h"
#include "nsTPromiseFlatString.h"
#include "nsThreadUtils.h"
#include "nsXULAppAPI.h"
extern "C" {
// Defined in intl/encoding_glue/src/lib.rs
const mozilla::Encoding* xmldecl_parse(const uint8_t* buf, size_t buf_len);
};
using namespace mozilla;
using namespace mozilla::dom;
/*
* Note that nsHtml5StreamParser implements cycle collecting AddRef and
* Release. Therefore, nsHtml5StreamParser must never be refcounted from
* the parser thread!
*
* To work around this limitation, runnables posted by the main thread to the
* parser thread hold their reference to the stream parser in an
* nsHtml5StreamParserPtr. Upon creation, nsHtml5StreamParserPtr addrefs the
* object it holds
* just like a regular nsRefPtr. This is OK, since the creation of the
* runnable and the nsHtml5StreamParserPtr happens on the main thread.
*
* When the runnable is done on the parser thread, the destructor of
* nsHtml5StreamParserPtr runs there. It doesn't call Release on the held object
* directly. Instead, it posts another runnable back to the main thread where
* that runnable calls Release on the wrapped object.
*
* When posting runnables in the other direction, the runnables have to be
* created on the main thread when nsHtml5StreamParser is instantiated and
* held for the lifetime of the nsHtml5StreamParser. This works, because the
* same runnabled can be dispatched multiple times and currently runnables
* posted from the parser thread to main thread don't need to wrap any
* runnable-specific data. (In the other direction, the runnables most notably
* wrap the byte data of the stream.)
*/
NS_IMPL_CYCLE_COLLECTING_ADDREF(nsHtml5StreamParser)
NS_IMPL_CYCLE_COLLECTING_RELEASE(nsHtml5StreamParser)
NS_INTERFACE_TABLE_HEAD(nsHtml5StreamParser)
NS_INTERFACE_TABLE(nsHtml5StreamParser, nsISupports)
NS_INTERFACE_TABLE_TO_MAP_SEGUE_CYCLE_COLLECTION(nsHtml5StreamParser)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTION_CLASS(nsHtml5StreamParser)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsHtml5StreamParser)
tmp->DropTimer();
NS_IMPL_CYCLE_COLLECTION_UNLINK(mRequest)
NS_IMPL_CYCLE_COLLECTION_UNLINK(mOwner)
tmp->mExecutorFlusher = nullptr;
tmp->mLoadFlusher = nullptr;
tmp->mExecutor = nullptr;
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsHtml5StreamParser)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mRequest)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mOwner)
// hack: count the strongly owned edge wrapped in the runnable
if (tmp->mExecutorFlusher) {
NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mExecutorFlusher->mExecutor");
cb.NoteXPCOMChild(static_cast<nsIContentSink*>(tmp->mExecutor));
}
// hack: count the strongly owned edge wrapped in the runnable
if (tmp->mLoadFlusher) {
NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mLoadFlusher->mExecutor");
cb.NoteXPCOMChild(static_cast<nsIContentSink*>(tmp->mExecutor));
}
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
class nsHtml5ExecutorFlusher : public Runnable {
private:
RefPtr<nsHtml5TreeOpExecutor> mExecutor;
public:
explicit nsHtml5ExecutorFlusher(nsHtml5TreeOpExecutor* aExecutor)
: Runnable("nsHtml5ExecutorFlusher"), mExecutor(aExecutor) {}
NS_IMETHOD Run() override {
if (!mExecutor->isInList()) {
Document* doc = mExecutor->GetDocument();
if (XRE_IsContentProcess() &&
nsContentUtils::
HighPriorityEventPendingForTopLevelDocumentBeforeContentfulPaint(
doc)) {
// Possible early paint pending, reuse the runnable and try to
// call RunFlushLoop later.
nsCOMPtr<nsIRunnable> flusher = this;
if (NS_SUCCEEDED(doc->Dispatch(flusher.forget()))) {
PROFILER_MARKER_UNTYPED("HighPrio blocking parser flushing(1)", DOM);
return NS_OK;
}
}
mExecutor->RunFlushLoop();
}
return NS_OK;
}
};
class nsHtml5LoadFlusher : public Runnable {
private:
RefPtr<nsHtml5TreeOpExecutor> mExecutor;
public:
explicit nsHtml5LoadFlusher(nsHtml5TreeOpExecutor* aExecutor)
: Runnable("nsHtml5LoadFlusher"), mExecutor(aExecutor) {}
NS_IMETHOD Run() override {
mExecutor->FlushSpeculativeLoads();
return NS_OK;
}
};
nsHtml5StreamParser::nsHtml5StreamParser(nsHtml5TreeOpExecutor* aExecutor,
nsHtml5Parser* aOwner,
eParserMode aMode)
: mBomState(eBomState::BOM_SNIFFING_NOT_STARTED),
mCharsetSource(kCharsetUninitialized),
mEncodingSwitchSource(kCharsetUninitialized),
mEncoding(X_USER_DEFINED_ENCODING), // Obviously bogus value to notice if
// not updated
mNeedsEncodingSwitchTo(nullptr),
mSeenEligibleMetaCharset(false),
mChardetEof(false),
#ifdef DEBUG
mStartedFeedingDetector(false),
mStartedFeedingDevTools(false),
#endif
mReparseForbidden(false),
mForceAutoDetection(false),
mChannelHadCharset(false),
mLookingForMetaCharset(false),
mStartsWithLtQuestion(false),
mLookingForXmlDeclarationForXmlViewSource(false),
mTemplatePushedOrHeadPopped(false),
mGtBuffer(nullptr),
mGtPos(0),
mLastBuffer(nullptr), // Will be filled when starting
mExecutor(aExecutor),
mTreeBuilder(new nsHtml5TreeBuilder(
(aMode == VIEW_SOURCE_HTML || aMode == VIEW_SOURCE_XML)
? nullptr
: mExecutor->GetStage(),
mExecutor->GetStage(), aMode == NORMAL)),
mTokenizer(
new nsHtml5Tokenizer(mTreeBuilder.get(), aMode == VIEW_SOURCE_XML)),
mTokenizerMutex("nsHtml5StreamParser mTokenizerMutex"),
mOwner(aOwner),
mLastWasCR(false),
mStreamState(eHtml5StreamState::STREAM_NOT_STARTED),
mSpeculating(false),
mAtEOF(false),
mSpeculationMutex("nsHtml5StreamParser mSpeculationMutex"),
mSpeculationFailureCount(0),
mNumBytesBuffered(0),
mTerminated(false),
mInterrupted(false),
mEventTarget(nsHtml5Module::GetStreamParserEventTarget()),
mExecutorFlusher(new nsHtml5ExecutorFlusher(aExecutor)),
mLoadFlusher(new nsHtml5LoadFlusher(aExecutor)),
mInitialEncodingWasFromParentFrame(false),
mHasHadErrors(false),
mDetectorHasSeenNonAscii(false),
mDecodingLocalFileWithoutTokenizing(false),
mBufferingBytes(false),
mFlushTimer(NS_NewTimer(mEventTarget)),
mFlushTimerMutex("nsHtml5StreamParser mFlushTimerMutex"),
mFlushTimerArmed(false),
mFlushTimerEverFired(false),
mMode(aMode) {
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
#ifdef DEBUG
mAtomTable.SetPermittedLookupEventTarget(mEventTarget);
#endif
mTokenizer->setInterner(&mAtomTable);
mTokenizer->setEncodingDeclarationHandler(this);
if (aMode == VIEW_SOURCE_HTML || aMode == VIEW_SOURCE_XML) {
nsHtml5Highlighter* highlighter =
new nsHtml5Highlighter(mExecutor->GetStage());
mTokenizer->EnableViewSource(highlighter); // takes ownership
mTreeBuilder->EnableViewSource(highlighter); // doesn't own
}
// There's a zeroing operator new for everything else
}
nsHtml5StreamParser::~nsHtml5StreamParser() {
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
mTokenizer->end();
#ifdef DEBUG
{
mozilla::MutexAutoLock flushTimerLock(mFlushTimerMutex);
MOZ_ASSERT(!mFlushTimer, "Flush timer was not dropped before dtor!");
}
mRequest = nullptr;
mUnicodeDecoder = nullptr;
mFirstBuffer = nullptr;
mExecutor = nullptr;
mTreeBuilder = nullptr;
mTokenizer = nullptr;
mOwner = nullptr;
#endif
}
nsresult nsHtml5StreamParser::GetChannel(nsIChannel** aChannel) {
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
return mRequest ? CallQueryInterface(mRequest, aChannel)
: NS_ERROR_NOT_AVAILABLE;
}
std::tuple<NotNull<const Encoding*>, nsCharsetSource>
nsHtml5StreamParser::GuessEncoding(bool aInitial) {
MOZ_ASSERT(
mCharsetSource != kCharsetFromFinalUserForcedAutoDetection &&
mCharsetSource !=
kCharsetFromFinalAutoDetectionWouldHaveBeenUTF8InitialWasASCII &&
mCharsetSource !=
kCharsetFromFinalAutoDetectionWouldNotHaveBeenUTF8Generic &&
mCharsetSource !=
kCharsetFromFinalAutoDetectionWouldNotHaveBeenUTF8GenericInitialWasASCII &&
mCharsetSource !=
kCharsetFromFinalAutoDetectionWouldNotHaveBeenUTF8Content &&
mCharsetSource !=
kCharsetFromFinalAutoDetectionWouldNotHaveBeenUTF8ContentInitialWasASCII &&
mCharsetSource !=
kCharsetFromFinalAutoDetectionWouldNotHaveBeenUTF8DependedOnTLD &&
mCharsetSource !=
kCharsetFromFinalAutoDetectionWouldNotHaveBeenUTF8DependedOnTLDInitialWasASCII &&
mCharsetSource != kCharsetFromFinalAutoDetectionFile);
auto ifHadBeenForced = mDetector->Guess(EmptyCString(), true);
auto encoding =
mForceAutoDetection
? ifHadBeenForced
: mDetector->Guess(mTLD, mDecodingLocalFileWithoutTokenizing);
nsCharsetSource source =
aInitial
? (mForceAutoDetection
? kCharsetFromInitialUserForcedAutoDetection
: (mDecodingLocalFileWithoutTokenizing
? kCharsetFromFinalAutoDetectionFile
: kCharsetFromInitialAutoDetectionWouldNotHaveBeenUTF8Generic))
: (mForceAutoDetection
? kCharsetFromFinalUserForcedAutoDetection
: (mDecodingLocalFileWithoutTokenizing
? kCharsetFromFinalAutoDetectionFile
: kCharsetFromFinalAutoDetectionWouldNotHaveBeenUTF8Generic));
if (source == kCharsetFromFinalAutoDetectionWouldNotHaveBeenUTF8Generic) {
if (encoding == ISO_2022_JP_ENCODING) {
if (EncodingDetector::TldMayAffectGuess(mTLD)) {
source = kCharsetFromFinalAutoDetectionWouldNotHaveBeenUTF8Content;
}
} else if (!mDetectorHasSeenNonAscii) {
source = kCharsetFromInitialAutoDetectionASCII; // deliberately Initial
} else if (ifHadBeenForced == UTF_8_ENCODING) {
MOZ_ASSERT(mCharsetSource == kCharsetFromInitialAutoDetectionASCII ||
mCharsetSource ==
kCharsetFromInitialAutoDetectionWouldHaveBeenUTF8 ||
mEncoding == ISO_2022_JP_ENCODING);
source = kCharsetFromFinalAutoDetectionWouldHaveBeenUTF8InitialWasASCII;
} else if (encoding != ifHadBeenForced) {
if (mCharsetSource == kCharsetFromInitialAutoDetectionASCII) {
source =
kCharsetFromFinalAutoDetectionWouldNotHaveBeenUTF8DependedOnTLDInitialWasASCII;
} else {
source =
kCharsetFromFinalAutoDetectionWouldNotHaveBeenUTF8DependedOnTLD;
}
} else if (EncodingDetector::TldMayAffectGuess(mTLD)) {
if (mCharsetSource == kCharsetFromInitialAutoDetectionASCII) {
source =
kCharsetFromFinalAutoDetectionWouldNotHaveBeenUTF8ContentInitialWasASCII;
} else {
source = kCharsetFromFinalAutoDetectionWouldNotHaveBeenUTF8Content;
}
} else if (mCharsetSource == kCharsetFromInitialAutoDetectionASCII) {
source =
kCharsetFromFinalAutoDetectionWouldNotHaveBeenUTF8GenericInitialWasASCII;
}
} else if (source ==
kCharsetFromInitialAutoDetectionWouldNotHaveBeenUTF8Generic) {
if (encoding == ISO_2022_JP_ENCODING) {
if (EncodingDetector::TldMayAffectGuess(mTLD)) {
source = kCharsetFromInitialAutoDetectionWouldNotHaveBeenUTF8Content;
}
} else if (!mDetectorHasSeenNonAscii) {
source = kCharsetFromInitialAutoDetectionASCII;
} else if (ifHadBeenForced == UTF_8_ENCODING) {
source = kCharsetFromInitialAutoDetectionWouldHaveBeenUTF8;
} else if (encoding != ifHadBeenForced) {
source =
kCharsetFromInitialAutoDetectionWouldNotHaveBeenUTF8DependedOnTLD;
} else if (EncodingDetector::TldMayAffectGuess(mTLD)) {
source = kCharsetFromInitialAutoDetectionWouldNotHaveBeenUTF8Content;
}
}
return {encoding, source};
}
void nsHtml5StreamParser::FeedDetector(Span<const uint8_t> aBuffer) {
#ifdef DEBUG
mStartedFeedingDetector = true;
#endif
MOZ_ASSERT(!mChardetEof);
mDetectorHasSeenNonAscii = mDetector->Feed(aBuffer, false);
}
void nsHtml5StreamParser::DetectorEof() {
#ifdef DEBUG
mStartedFeedingDetector = true;
#endif
if (mChardetEof) {
return;
}
mChardetEof = true;
mDetectorHasSeenNonAscii = mDetector->Feed(Span<const uint8_t>(), true);
}
void nsHtml5StreamParser::SetViewSourceTitle(nsIURI* aURL) {
MOZ_ASSERT(NS_IsMainThread());
BrowsingContext* browsingContext =
mExecutor->GetDocument()->GetBrowsingContext();
if (browsingContext && browsingContext->WatchedByDevTools()) {
mURIToSendToDevtools = aURL;
nsID uuid;
nsresult rv = nsID::GenerateUUIDInPlace(uuid);
if (!NS_FAILED(rv)) {
char buffer[NSID_LENGTH];
uuid.ToProvidedString(buffer);
mUUIDForDevtools = NS_ConvertASCIItoUTF16(buffer);
}
}
if (aURL) {
nsCOMPtr<nsIURI> temp;
if (aURL->SchemeIs("view-source")) {
nsCOMPtr<nsINestedURI> nested = do_QueryInterface(aURL);
nested->GetInnerURI(getter_AddRefs(temp));
} else {
temp = aURL;
}
if (temp->SchemeIs("data")) {
// Avoid showing potentially huge data: URLs. The three last bytes are
// UTF-8 for an ellipsis.
mViewSourceTitle.AssignLiteral("data:\xE2\x80\xA6");
} else {
nsresult rv = temp->GetSpec(mViewSourceTitle);
if (NS_FAILED(rv)) {
mViewSourceTitle.AssignLiteral("\xE2\x80\xA6");
}
}
}
}
nsresult
nsHtml5StreamParser::SetupDecodingAndWriteSniffingBufferAndCurrentSegment(
Span<const uint8_t> aPrefix, Span<const uint8_t> aFromSegment) {
NS_ASSERTION(IsParserThread(), "Wrong thread!");
mUnicodeDecoder = mEncoding->NewDecoderWithBOMRemoval();
nsresult rv = WriteStreamBytes(aPrefix);
NS_ENSURE_SUCCESS(rv, rv);
return WriteStreamBytes(aFromSegment);
}
void nsHtml5StreamParser::SetupDecodingFromBom(
NotNull<const Encoding*> aEncoding) {
MOZ_ASSERT(IsParserThread(), "Wrong thread!");
mEncoding = aEncoding;
mDecodingLocalFileWithoutTokenizing = false;
mLookingForMetaCharset = false;
mBufferingBytes = false;
mUnicodeDecoder = mEncoding->NewDecoderWithoutBOMHandling();
mCharsetSource = kCharsetFromByteOrderMark;
mForceAutoDetection = false;
mTreeBuilder->SetDocumentCharset(mEncoding, mCharsetSource, false);
mBomState = BOM_SNIFFING_OVER;
if (mMode == VIEW_SOURCE_HTML) {
mTokenizer->StartViewSourceCharacters();
}
}
void nsHtml5StreamParser::SetupDecodingFromUtf16BogoXml(
NotNull<const Encoding*> aEncoding) {
MOZ_ASSERT(IsParserThread(), "Wrong thread!");
mEncoding = aEncoding;
mDecodingLocalFileWithoutTokenizing = false;
mLookingForMetaCharset = false;
mBufferingBytes = false;
mUnicodeDecoder = mEncoding->NewDecoderWithoutBOMHandling();
mCharsetSource = kCharsetFromXmlDeclarationUtf16;
mForceAutoDetection = false;
mTreeBuilder->SetDocumentCharset(mEncoding, mCharsetSource, false);
mBomState = BOM_SNIFFING_OVER;
if (mMode == VIEW_SOURCE_HTML) {
mTokenizer->StartViewSourceCharacters();
}
auto dst = mLastBuffer->TailAsSpan(READ_BUFFER_SIZE);
dst[0] = '<';
dst[1] = '?';
dst[2] = 'x';
mLastBuffer->AdvanceEnd(3);
MOZ_ASSERT(!mStartedFeedingDevTools);
OnNewContent(dst.To(3));
}
size_t nsHtml5StreamParser::LengthOfLtContainingPrefixInSecondBuffer() {
MOZ_ASSERT(mBufferedBytes.Length() <= 2);
if (mBufferedBytes.Length() < 2) {
return 0;
}
Buffer<uint8_t>& second = mBufferedBytes[1];
const uint8_t* elements = second.Elements();
const uint8_t* lt = (const uint8_t*)memchr(elements, '>', second.Length());
if (lt) {
return (lt - elements) + 1;
}
return 0;
}
nsresult nsHtml5StreamParser::SniffStreamBytes(Span<const uint8_t> aFromSegment,
bool aEof) {
MOZ_ASSERT(IsParserThread(), "Wrong thread!");
MOZ_ASSERT_IF(aEof, aFromSegment.IsEmpty());
if (mCharsetSource >=
kCharsetFromFinalAutoDetectionWouldHaveBeenUTF8InitialWasASCII &&
mCharsetSource <= kCharsetFromFinalUserForcedAutoDetection) {
if (mMode == PLAIN_TEXT || mMode == VIEW_SOURCE_PLAIN) {
mTreeBuilder->MaybeComplainAboutCharset("EncDetectorReloadPlain", true,
0);
} else {
mTreeBuilder->MaybeComplainAboutCharset("EncDetectorReload", true, 0);
}
}
// mEncoding and mCharsetSource potentially have come from channel or higher
// by now. If we find a BOM, SetupDecodingFromBom() will overwrite them.
// If we don't find a BOM, the previously set values of mEncoding and
// mCharsetSource are not modified by the BOM sniffing here.
static uint8_t utf8[] = {0xEF, 0xBB};
static uint8_t utf16le[] = {0xFF};
static uint8_t utf16be[] = {0xFE};
static uint8_t utf16leXml[] = {'<', 0x00, '?', 0x00, 'x'};
static uint8_t utf16beXml[] = {0x00, '<', 0x00, '?', 0x00};
// Buffer for replaying past bytes based on state machine state. If
// writing this from scratch, probably wouldn't do it this way, but
// let's keep the changes to a minimum.
const uint8_t* prefix = utf8;
size_t prefixLength = 0;
if (aEof && mBomState == BOM_SNIFFING_NOT_STARTED) {
// Avoid handling aEof in the BOM_SNIFFING_NOT_STARTED state below.
mBomState = BOM_SNIFFING_OVER;
}
for (size_t i = 0;
(i < aFromSegment.Length() && mBomState != BOM_SNIFFING_OVER) || aEof;
i++) {
switch (mBomState) {
case BOM_SNIFFING_NOT_STARTED:
MOZ_ASSERT(i == 0, "Bad BOM sniffing state.");
MOZ_ASSERT(!aEof, "Should have checked for aEof above!");
switch (aFromSegment[0]) {
case 0xEF:
mBomState = SEEN_UTF_8_FIRST_BYTE;
break;
case 0xFF:
mBomState = SEEN_UTF_16_LE_FIRST_BYTE;
break;
case 0xFE:
mBomState = SEEN_UTF_16_BE_FIRST_BYTE;
break;
case 0x00:
if (mCharsetSource < kCharsetFromXmlDeclarationUtf16 &&
mCharsetSource != kCharsetFromChannel) {
mBomState = SEEN_UTF_16_BE_XML_FIRST;
} else {
mBomState = BOM_SNIFFING_OVER;
}
break;
case '<':
if (mCharsetSource < kCharsetFromXmlDeclarationUtf16 &&
mCharsetSource != kCharsetFromChannel) {
mBomState = SEEN_UTF_16_LE_XML_FIRST;
} else {
mBomState = BOM_SNIFFING_OVER;
}
break;
default:
mBomState = BOM_SNIFFING_OVER;
break;
}
break;
case SEEN_UTF_16_LE_FIRST_BYTE:
if (!aEof && aFromSegment[i] == 0xFE) {
SetupDecodingFromBom(UTF_16LE_ENCODING);
return WriteStreamBytes(aFromSegment.From(i + 1));
}
prefix = utf16le;
prefixLength = 1 - i;
mBomState = BOM_SNIFFING_OVER;
break;
case SEEN_UTF_16_BE_FIRST_BYTE:
if (!aEof && aFromSegment[i] == 0xFF) {
SetupDecodingFromBom(UTF_16BE_ENCODING);
return WriteStreamBytes(aFromSegment.From(i + 1));
}
prefix = utf16be;
prefixLength = 1 - i;
mBomState = BOM_SNIFFING_OVER;
break;
case SEEN_UTF_8_FIRST_BYTE:
if (!aEof && aFromSegment[i] == 0xBB) {
mBomState = SEEN_UTF_8_SECOND_BYTE;
} else {
prefixLength = 1 - i;
mBomState = BOM_SNIFFING_OVER;
}
break;
case SEEN_UTF_8_SECOND_BYTE:
if (!aEof && aFromSegment[i] == 0xBF) {
SetupDecodingFromBom(UTF_8_ENCODING);
return WriteStreamBytes(aFromSegment.From(i + 1));
}
prefixLength = 2 - i;
mBomState = BOM_SNIFFING_OVER;
break;
case SEEN_UTF_16_BE_XML_FIRST:
if (!aEof && aFromSegment[i] == '<') {
mBomState = SEEN_UTF_16_BE_XML_SECOND;
} else {
prefix = utf16beXml;
prefixLength = 1 - i;
mBomState = BOM_SNIFFING_OVER;
}
break;
case SEEN_UTF_16_BE_XML_SECOND:
if (!aEof && aFromSegment[i] == 0x00) {
mBomState = SEEN_UTF_16_BE_XML_THIRD;
} else {
prefix = utf16beXml;
prefixLength = 2 - i;
mBomState = BOM_SNIFFING_OVER;
}
break;
case SEEN_UTF_16_BE_XML_THIRD:
if (!aEof && aFromSegment[i] == '?') {
mBomState = SEEN_UTF_16_BE_XML_FOURTH;
} else {
prefix = utf16beXml;
prefixLength = 3 - i;
mBomState = BOM_SNIFFING_OVER;
}
break;
case SEEN_UTF_16_BE_XML_FOURTH:
if (!aEof && aFromSegment[i] == 0x00) {
mBomState = SEEN_UTF_16_BE_XML_FIFTH;
} else {
prefix = utf16beXml;
prefixLength = 4 - i;
mBomState = BOM_SNIFFING_OVER;
}
break;
case SEEN_UTF_16_BE_XML_FIFTH:
if (!aEof && aFromSegment[i] == 'x') {
SetupDecodingFromUtf16BogoXml(UTF_16BE_ENCODING);
return WriteStreamBytes(aFromSegment.From(i + 1));
}
prefix = utf16beXml;
prefixLength = 5 - i;
mBomState = BOM_SNIFFING_OVER;
break;
case SEEN_UTF_16_LE_XML_FIRST:
if (!aEof && aFromSegment[i] == 0x00) {
mBomState = SEEN_UTF_16_LE_XML_SECOND;
} else {
if (!aEof && aFromSegment[i] == '?' &&
!(mMode == PLAIN_TEXT || mMode == VIEW_SOURCE_PLAIN)) {
mStartsWithLtQuestion = true;
}
prefix = utf16leXml;
prefixLength = 1 - i;
mBomState = BOM_SNIFFING_OVER;
}
break;
case SEEN_UTF_16_LE_XML_SECOND:
if (!aEof && aFromSegment[i] == '?') {
mBomState = SEEN_UTF_16_LE_XML_THIRD;
} else {
prefix = utf16leXml;
prefixLength = 2 - i;
mBomState = BOM_SNIFFING_OVER;
}
break;
case SEEN_UTF_16_LE_XML_THIRD:
if (!aEof && aFromSegment[i] == 0x00) {
mBomState = SEEN_UTF_16_LE_XML_FOURTH;
} else {
prefix = utf16leXml;
prefixLength = 3 - i;
mBomState = BOM_SNIFFING_OVER;
}
break;
case SEEN_UTF_16_LE_XML_FOURTH:
if (!aEof && aFromSegment[i] == 'x') {
mBomState = SEEN_UTF_16_LE_XML_FIFTH;
} else {
prefix = utf16leXml;
prefixLength = 4 - i;
mBomState = BOM_SNIFFING_OVER;
}
break;
case SEEN_UTF_16_LE_XML_FIFTH:
if (!aEof && aFromSegment[i] == 0x00) {
SetupDecodingFromUtf16BogoXml(UTF_16LE_ENCODING);
return WriteStreamBytes(aFromSegment.From(i + 1));
}
prefix = utf16leXml;
prefixLength = 5 - i;
mBomState = BOM_SNIFFING_OVER;
break;
default:
mBomState = BOM_SNIFFING_OVER;
break;
}
if (aEof) {
break;
}
}
// if we get here, there either was no BOM or the BOM sniffing isn't complete
// yet
MOZ_ASSERT(mCharsetSource != kCharsetFromByteOrderMark,
"Should not come here if BOM was found.");
MOZ_ASSERT(mCharsetSource != kCharsetFromXmlDeclarationUtf16,
"Should not come here if UTF-16 bogo-XML declaration was found.");
MOZ_ASSERT(mCharsetSource != kCharsetFromOtherComponent,
"kCharsetFromOtherComponent is for XSLT.");
if (mBomState == BOM_SNIFFING_OVER) {
if (mMode == VIEW_SOURCE_XML && mStartsWithLtQuestion &&
mCharsetSource < kCharsetFromChannel) {
// Sniff for XML declaration only.
MOZ_ASSERT(!mLookingForXmlDeclarationForXmlViewSource);
MOZ_ASSERT(!aEof);
MOZ_ASSERT(!mLookingForMetaCharset);
MOZ_ASSERT(!mDecodingLocalFileWithoutTokenizing);
// Maybe we've already buffered a '>'.
MOZ_ASSERT(!mBufferedBytes.IsEmpty(),
"How did at least <? not get buffered?");
Buffer<uint8_t>& first = mBufferedBytes[0];
const Encoding* encoding =
xmldecl_parse(first.Elements(), first.Length());
if (encoding) {
mEncoding = WrapNotNull(encoding);
mCharsetSource = kCharsetFromXmlDeclaration;
} else if (memchr(first.Elements(), '>', first.Length())) {
// There was a '>', but an encoding still wasn't found.
; // fall through to commit to the UTF-8 default.
} else if (size_t lengthOfPrefix =
LengthOfLtContainingPrefixInSecondBuffer()) {
// This can only happen if the first buffer was a lone '<', because
// we come here upon seeing the second byte '?' if the first two bytes
// were "<?". That is, the only way how we aren't dealing with the first
// buffer is if the first buffer only contained a single '<' and we are
// dealing with the second buffer that starts with '?'.
MOZ_ASSERT(first.Length() == 1);
MOZ_ASSERT(mBufferedBytes[1][0] == '?');
// Our scanner for XML declaration-like syntax wants to see a contiguous
// buffer, so let's linearize the data. (Ideally, the XML declaration
// scanner would be incremental, but this is the rare path anyway.)
Vector<uint8_t> contiguous;
if (!contiguous.append(first.Elements(), first.Length())) {
MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
return NS_ERROR_OUT_OF_MEMORY;
}
if (!contiguous.append(mBufferedBytes[1].Elements(), lengthOfPrefix)) {
MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
return NS_ERROR_OUT_OF_MEMORY;
}
encoding = xmldecl_parse(contiguous.begin(), contiguous.length());
if (encoding) {
mEncoding = WrapNotNull(encoding);
mCharsetSource = kCharsetFromXmlDeclaration;
}
// else no XML decl, commit to the UTF-8 default.
} else {
MOZ_ASSERT(mBufferingBytes);
mLookingForXmlDeclarationForXmlViewSource = true;
return NS_OK;
}
} else if (mMode != VIEW_SOURCE_XML &&
(mForceAutoDetection || mCharsetSource < kCharsetFromChannel)) {
// In order to use the buffering logic for meta with mForceAutoDetection,
// we set mLookingForMetaCharset but still actually potentially ignore the
// meta.
mFirstBufferOfMetaScan = mFirstBuffer;
MOZ_ASSERT(mLookingForMetaCharset);
if (mMode == VIEW_SOURCE_HTML) {
auto r = mTokenizer->FlushViewSource();
if (r.isErr()) {
return r.unwrapErr();
}
}
auto r = mTreeBuilder->Flush();
if (r.isErr()) {
return r.unwrapErr();
}
// Encoding committer flushes the ops on the main thread.
mozilla::MutexAutoLock speculationAutoLock(mSpeculationMutex);
nsHtml5Speculation* speculation = new nsHtml5Speculation(
mFirstBuffer, mFirstBuffer->getStart(), mTokenizer->getLineNumber(),
mTokenizer->getColumnNumber(), mTreeBuilder->newSnapshot());
MOZ_ASSERT(!mFlushTimerArmed, "How did we end up arming the timer?");
if (mMode == VIEW_SOURCE_HTML) {
mTokenizer->SetViewSourceOpSink(speculation);
mTokenizer->StartViewSourceCharacters();
} else {
MOZ_ASSERT(mMode != VIEW_SOURCE_XML);
mTreeBuilder->SetOpSink(speculation);
}
mSpeculations.AppendElement(speculation); // adopts the pointer
mSpeculating = true;
} else {
mLookingForMetaCharset = false;
mBufferingBytes = false;
mDecodingLocalFileWithoutTokenizing = false;
if (mMode == VIEW_SOURCE_HTML) {
mTokenizer->StartViewSourceCharacters();
}
}
mTreeBuilder->SetDocumentCharset(mEncoding, mCharsetSource, false);
return SetupDecodingAndWriteSniffingBufferAndCurrentSegment(
Span(prefix, prefixLength), aFromSegment);
}
return NS_OK;
}
class AddContentRunnable : public Runnable {
public:
AddContentRunnable(const nsAString& aParserID, nsIURI* aURI,
Span<const char16_t> aData, bool aComplete)
: Runnable("AddContent") {
nsAutoCString spec;
aURI->GetSpec(spec);
mData.mUri.Construct(NS_ConvertUTF8toUTF16(spec));
mData.mParserID.Construct(aParserID);
mData.mContents.Construct(aData.Elements(), aData.Length());
mData.mComplete.Construct(aComplete);
}
NS_IMETHOD Run() override {
nsAutoString json;
if (!mData.ToJSON(json)) {
return NS_ERROR_FAILURE;
}
nsCOMPtr<nsIObserverService> obsService = services::GetObserverService();
if (obsService) {
obsService->NotifyObservers(nullptr, "devtools-html-content",
PromiseFlatString(json).get());
}
return NS_OK;
}
HTMLContent mData;
};
inline void nsHtml5StreamParser::OnNewContent(Span<const char16_t> aData) {
#ifdef DEBUG
mStartedFeedingDevTools = true;
#endif
if (mURIToSendToDevtools) {
if (aData.IsEmpty()) {
// Optimize out the runnable.
return;
}
NS_DispatchToMainThread(new AddContentRunnable(mUUIDForDevtools,
mURIToSendToDevtools, aData,
/* aComplete */ false));
}
}
inline void nsHtml5StreamParser::OnContentComplete() {
#ifdef DEBUG
mStartedFeedingDevTools = true;
#endif
if (mURIToSendToDevtools) {
NS_DispatchToMainThread(new AddContentRunnable(
mUUIDForDevtools, mURIToSendToDevtools, Span<const char16_t>(),
/* aComplete */ true));
mURIToSendToDevtools = nullptr;
}
}
nsresult nsHtml5StreamParser::WriteStreamBytes(
Span<const uint8_t> aFromSegment) {
NS_ASSERTION(IsParserThread(), "Wrong thread!");
mTokenizerMutex.AssertCurrentThreadOwns();
// mLastBuffer should always point to a buffer of the size
// READ_BUFFER_SIZE.
if (!mLastBuffer) {
NS_WARNING("mLastBuffer should not be null!");
MarkAsBroken(NS_ERROR_NULL_POINTER);
return NS_ERROR_NULL_POINTER;
}
size_t totalRead = 0;
auto src = aFromSegment;
for (;;) {
auto dst = mLastBuffer->TailAsSpan(READ_BUFFER_SIZE);
auto [result, read, written, hadErrors] =
mUnicodeDecoder->DecodeToUTF16(src, dst, false);
if (!(mLookingForMetaCharset || mDecodingLocalFileWithoutTokenizing)) {
OnNewContent(dst.To(written));
}
if (hadErrors && !mHasHadErrors) {
mHasHadErrors = true;
if (mEncoding == UTF_8_ENCODING) {
mTreeBuilder->TryToEnableEncodingMenu();
}
}
src = src.From(read);
totalRead += read;
mLastBuffer->AdvanceEnd(written);
if (result == kOutputFull) {
RefPtr<nsHtml5OwningUTF16Buffer> newBuf =
nsHtml5OwningUTF16Buffer::FalliblyCreate(READ_BUFFER_SIZE);
if (!newBuf) {
MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
return NS_ERROR_OUT_OF_MEMORY;
}
mLastBuffer = (mLastBuffer->next = std::move(newBuf));
} else {
MOZ_ASSERT(totalRead == aFromSegment.Length(),
"The Unicode decoder consumed the wrong number of bytes.");
(void)totalRead;
if (!mLookingForMetaCharset && mDecodingLocalFileWithoutTokenizing &&
mNumBytesBuffered == LOCAL_FILE_UTF_8_BUFFER_SIZE) {
MOZ_ASSERT(!mStartedFeedingDetector);
for (auto&& buffer : mBufferedBytes) {
FeedDetector(buffer);
}
// If the file is exactly LOCAL_FILE_UTF_8_BUFFER_SIZE bytes long
// we end up not considering the EOF. That's not fatal, since we
// don't consider the EOF if the file is
// LOCAL_FILE_UTF_8_BUFFER_SIZE + 1 bytes long.
auto [encoding, source] = GuessEncoding(true);
mCharsetSource = source;
if (encoding != mEncoding) {
mEncoding = encoding;
nsresult rv = ReDecodeLocalFile();
if (NS_FAILED(rv)) {
return rv;
}
} else {
MOZ_ASSERT(mEncoding == UTF_8_ENCODING);
nsresult rv = CommitLocalFileToEncoding();
if (NS_FAILED(rv)) {
return rv;
}
}
}
return NS_OK;
}
}
}
[[nodiscard]] nsresult nsHtml5StreamParser::ReDecodeLocalFile() {
MOZ_ASSERT(mDecodingLocalFileWithoutTokenizing && !mLookingForMetaCharset);
MOZ_ASSERT(mFirstBufferOfMetaScan);
MOZ_ASSERT(mCharsetSource == kCharsetFromFinalAutoDetectionFile ||
(mForceAutoDetection &&
mCharsetSource == kCharsetFromInitialUserForcedAutoDetection));
DiscardMetaSpeculation();
MOZ_ASSERT(mEncoding != UTF_8_ENCODING);
mDecodingLocalFileWithoutTokenizing = false;
mEncoding->NewDecoderWithBOMRemovalInto(*mUnicodeDecoder);
mHasHadErrors = false;
// Throw away previous decoded data
mLastBuffer = mFirstBuffer;
mLastBuffer->next = nullptr;
mLastBuffer->setStart(0);
mLastBuffer->setEnd(0);
mBufferingBytes = false;
mForceAutoDetection = false; // To stop feeding the detector
mFirstBufferOfMetaScan = nullptr;
mTreeBuilder->SetDocumentCharset(mEncoding, mCharsetSource, true);
// Decode again
for (auto&& buffer : mBufferedBytes) {
DoDataAvailable(buffer);
}
if (mMode == VIEW_SOURCE_HTML) {
auto r = mTokenizer->FlushViewSource();
if (r.isErr()) {
return r.unwrapErr();
}
}
auto r = mTreeBuilder->Flush();
if (r.isErr()) {
return r.unwrapErr();
}
return NS_OK;
}
[[nodiscard]] nsresult nsHtml5StreamParser::CommitLocalFileToEncoding() {
MOZ_ASSERT(mDecodingLocalFileWithoutTokenizing && !mLookingForMetaCharset);
MOZ_ASSERT(mFirstBufferOfMetaScan);
mDecodingLocalFileWithoutTokenizing = false;
MOZ_ASSERT(mCharsetSource == kCharsetFromFinalAutoDetectionFile ||
(mForceAutoDetection &&
mCharsetSource == kCharsetFromInitialUserForcedAutoDetection));
MOZ_ASSERT(mEncoding == UTF_8_ENCODING);
MOZ_ASSERT(!mStartedFeedingDevTools);
if (mURIToSendToDevtools) {
nsHtml5OwningUTF16Buffer* buffer = mFirstBufferOfMetaScan;
while (buffer) {
Span<const char16_t> data(buffer->getBuffer() + buffer->getStart(),
buffer->getLength());
OnNewContent(data);
buffer = buffer->next;
}
}
mFirstBufferOfMetaScan = nullptr;
mBufferingBytes = false;
mForceAutoDetection = false; // To stop feeding the detector
mTreeBuilder->SetDocumentCharset(mEncoding, mCharsetSource, true);
if (mMode == VIEW_SOURCE_HTML) {
auto r = mTokenizer->FlushViewSource();
if (r.isErr()) {
return r.unwrapErr();
}
}
auto r = mTreeBuilder->Flush();
if (r.isErr()) {
return r.unwrapErr();
}
return NS_OK;
}
class MaybeRunCollector : public Runnable {
public:
explicit MaybeRunCollector(nsIDocShell* aDocShell)
: Runnable("MaybeRunCollector"), mDocShell(aDocShell) {}
NS_IMETHOD Run() override {
nsJSContext::MaybeRunNextCollectorSlice(mDocShell,
JS::GCReason::HTML_PARSER);
return NS_OK;
}
nsCOMPtr<nsIDocShell> mDocShell;
};
nsresult nsHtml5StreamParser::OnStartRequest(nsIRequest* aRequest) {
MOZ_RELEASE_ASSERT(STREAM_NOT_STARTED == mStreamState,
"Got OnStartRequest when the stream had already started.");
MOZ_ASSERT(
!mExecutor->HasStarted(),
"Got OnStartRequest at the wrong stage in the executor life cycle.");
MOZ_ASSERT(NS_IsMainThread(), "Wrong thread!");
// To avoid the cost of instantiating the detector when it's not needed,
// let's instantiate only if we make it out of this method with the
// intent to use it.
auto detectorCreator = MakeScopeExit([&] {
if ((mForceAutoDetection || mCharsetSource < kCharsetFromParentFrame) ||
!(mMode == LOAD_AS_DATA || mMode == VIEW_SOURCE_XML)) {
mDetector = mozilla::EncodingDetector::Create();
}
});
mRequest = aRequest;
mStreamState = STREAM_BEING_READ;
// For View Source, the parser should run with scripts "enabled" if a normal
// load would have scripts enabled.
bool scriptingEnabled =
mMode == LOAD_AS_DATA ? false : mExecutor->IsScriptEnabled();
mOwner->StartTokenizer(scriptingEnabled);
MOZ_ASSERT(!mDecodingLocalFileWithoutTokenizing);
bool isSrcdoc = false;
nsCOMPtr<nsIChannel> channel;
nsresult rv = GetChannel(getter_AddRefs(channel));
if (NS_SUCCEEDED(rv)) {
isSrcdoc = NS_IsSrcdocChannel(channel);
if (!isSrcdoc && mCharsetSource <= kCharsetFromFallback) {
nsCOMPtr<nsIURI> originalURI;
rv = channel->GetOriginalURI(getter_AddRefs(originalURI));
if (NS_SUCCEEDED(rv)) {
if (originalURI->SchemeIs("resource")) {
mCharsetSource = kCharsetFromBuiltIn;
mEncoding = UTF_8_ENCODING;
mTreeBuilder->SetDocumentCharset(mEncoding, mCharsetSource, false);
} else {
nsCOMPtr<nsIURI> currentURI;
rv = channel->GetURI(getter_AddRefs(currentURI));
if (NS_SUCCEEDED(rv)) {
nsCOMPtr<nsIURI> innermost = NS_GetInnermostURI(currentURI);
if (innermost->SchemeIs("file")) {
MOZ_ASSERT(mEncoding == UTF_8_ENCODING);
if (!(mMode == LOAD_AS_DATA || mMode == VIEW_SOURCE_XML)) {
mDecodingLocalFileWithoutTokenizing = true;
}
} else {
nsAutoCString host;
innermost->GetAsciiHost(host);
if (!host.IsEmpty()) {
// First let's see if the host is DNS-absolute and ends with a
// dot and get rid of that one.
if (host.Last() == '.') {
host.SetLength(host.Length() - 1);
}
int32_t index = host.RFindChar('.');
if (index != kNotFound) {
// We tolerate an IPv4 component as generic "TLD", so don't
// bother checking.
ToLowerCase(
Substring(host, index + 1, host.Length() - (index + 1)),
mTLD);
}
}
}
}
}
}
}
}
mTreeBuilder->setIsSrcdocDocument(isSrcdoc);
mTreeBuilder->setScriptingEnabled(scriptingEnabled);
mTreeBuilder->SetPreventScriptExecution(
!((mMode == NORMAL) && scriptingEnabled));
mTreeBuilder->setAllowDeclarativeShadowRoots(
mExecutor->GetDocument()->AllowsDeclarativeShadowRoots());
mTokenizer->start();
mExecutor->Start();
mExecutor->StartReadingFromStage();
if (mMode == PLAIN_TEXT) {
mTreeBuilder->StartPlainText();
mTokenizer->StartPlainText();
MOZ_ASSERT(
mTemplatePushedOrHeadPopped); // Needed to force 1024-byte sniffing
// Flush the ops to put them where ContinueAfterScriptsOrEncodingCommitment
// can find them.
auto r = mTreeBuilder->Flush();
if (r.isErr()) {
return mExecutor->MarkAsBroken(r.unwrapErr());
}
} else if (mMode == VIEW_SOURCE_PLAIN) {
nsAutoString viewSourceTitle;
CopyUTF8toUTF16(mViewSourceTitle, viewSourceTitle);
mTreeBuilder->EnsureBufferSpace(viewSourceTitle.Length());
mTreeBuilder->StartPlainTextViewSource(viewSourceTitle);
mTokenizer->StartPlainText();
MOZ_ASSERT(
mTemplatePushedOrHeadPopped); // Needed to force 1024-byte sniffing
// Flush the ops to put them where ContinueAfterScriptsOrEncodingCommitment
// can find them.
auto r = mTreeBuilder->Flush();
if (r.isErr()) {
return mExecutor->MarkAsBroken(r.unwrapErr());
}
} else if (mMode == VIEW_SOURCE_HTML || mMode == VIEW_SOURCE_XML) {
// Generate and flush the View Source document up to and including the
// pre element start.
mTokenizer->StartViewSource(NS_ConvertUTF8toUTF16(mViewSourceTitle));
if (mMode == VIEW_SOURCE_XML) {
mTokenizer->StartViewSourceCharacters();
}
// Flush the ops to put them where ContinueAfterScriptsOrEncodingCommitment
// can find them.
auto r = mTokenizer->FlushViewSource();
if (r.isErr()) {
return mExecutor->MarkAsBroken(r.unwrapErr());
}
}
/*
* If you move the following line, be very careful not to cause
* WillBuildModel to be called before the document has had its
* script global object set.
*/
rv = mExecutor->WillBuildModel();
NS_ENSURE_SUCCESS(rv, rv);
RefPtr<nsHtml5OwningUTF16Buffer> newBuf =
nsHtml5OwningUTF16Buffer::FalliblyCreate(READ_BUFFER_SIZE);
if (!newBuf) {
// marks this stream parser as terminated,
// which prevents entry to code paths that
// would use mFirstBuffer or mLastBuffer.
return mExecutor->MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
}
MOZ_ASSERT(!mFirstBuffer, "How come we have the first buffer set?");
MOZ_ASSERT(!mLastBuffer, "How come we have the last buffer set?");
mFirstBuffer = mLastBuffer = newBuf;
rv = NS_OK;
nsCOMPtr<nsIHttpChannel> httpChannel(do_QueryInterface(mRequest, &rv));
if (NS_SUCCEEDED(rv)) {
nsAutoCString method;
Unused << httpChannel->GetRequestMethod(method);
// XXX does Necko have a way to renavigate POST, etc. without hitting
// the network?
if (!method.EqualsLiteral("GET")) {
// This is the old Gecko behavior but the HTML5 spec disagrees.
// Don't reparse on POST.
mReparseForbidden = true;
}
}
// Attempt to retarget delivery of data (via OnDataAvailable) to the parser
// thread, rather than through the main thread.
nsCOMPtr<nsIThreadRetargetableRequest> threadRetargetableRequest =
do_QueryInterface(mRequest, &rv);
if (threadRetargetableRequest) {
rv = threadRetargetableRequest->RetargetDeliveryTo(mEventTarget);
if (NS_SUCCEEDED(rv)) {
// Parser thread should be now ready to get data from necko and parse it
// and main thread might have a chance to process a collector slice.
// We need to do this asynchronously so that necko may continue processing
// the request.
nsCOMPtr<nsIRunnable> runnable =
new MaybeRunCollector(mExecutor->GetDocument()->GetDocShell());
mozilla::SchedulerGroup::Dispatch(runnable.forget());
}
}
if (NS_FAILED(rv)) {
NS_WARNING("Failed to retarget HTML data delivery to the parser thread.");
}
if (mCharsetSource == kCharsetFromParentFrame) {
// Remember this for error reporting.
mInitialEncodingWasFromParentFrame = true;
MOZ_ASSERT(!mDecodingLocalFileWithoutTokenizing);
}
if (mForceAutoDetection || mCharsetSource < kCharsetFromChannel) {
mBufferingBytes = true;
if (mMode != VIEW_SOURCE_XML) {
// We need to set mLookingForMetaCharset to true here in case the first
// buffer to arrive is larger than 1024. We need the code that splits
// the buffers at 1024 bytes to work even in that case.
mLookingForMetaCharset = true;
}
}
if (mCharsetSource < kCharsetFromUtf8OnlyMime) {
// we aren't ready to commit to an encoding yet
// leave converter uninstantiated for now
return NS_OK;
}
MOZ_ASSERT(!(mMode == VIEW_SOURCE_HTML || mMode == VIEW_SOURCE_XML));
MOZ_ASSERT(mEncoding == UTF_8_ENCODING,
"How come UTF-8-only MIME type didn't set encoding to UTF-8?");
// We are loading JSON/WebVTT/etc. into a browsing context.
// There's no need to remove the BOM manually here, because
// the UTF-8 decoder removes it.
mReparseForbidden = true;
mForceAutoDetection = false;
// Instantiate the converter here to avoid BOM sniffing.
mDecodingLocalFileWithoutTokenizing = false;
mUnicodeDecoder = mEncoding->NewDecoderWithBOMRemoval();
return NS_OK;
}
void nsHtml5StreamParser::DoStopRequest() {
MOZ_ASSERT(IsParserThread(), "Wrong thread!");
MOZ_RELEASE_ASSERT(STREAM_BEING_READ == mStreamState,
"Stream ended without being open.");
mTokenizerMutex.AssertCurrentThreadOwns();
auto guard = MakeScopeExit([&] { OnContentComplete(); });
if (IsTerminated()) {
return;
}
if (MOZ_UNLIKELY(mLookingForXmlDeclarationForXmlViewSource)) {
mLookingForXmlDeclarationForXmlViewSource = false;
mBufferingBytes = false;
mUnicodeDecoder = mEncoding->NewDecoderWithoutBOMHandling();
mTreeBuilder->SetDocumentCharset(mEncoding, mCharsetSource, false);
for (auto&& buffer : mBufferedBytes) {
nsresult rv = WriteStreamBytes(buffer);
if (NS_FAILED(rv)) {
MarkAsBroken(rv);
return;
}
}
} else if (!mUnicodeDecoder) {
nsresult rv;
if (NS_FAILED(rv = SniffStreamBytes(Span<const uint8_t>(), true))) {
MarkAsBroken(rv);
return;
}
}
MOZ_ASSERT(mUnicodeDecoder,
"Should have a decoder after finalizing sniffing.");
// mLastBuffer should always point to a buffer of the size
// READ_BUFFER_SIZE.
if (!mLastBuffer) {
NS_WARNING("mLastBuffer should not be null!");
MarkAsBroken(NS_ERROR_NULL_POINTER);
return;
}
Span<uint8_t> src; // empty span
for (;;) {
auto dst = mLastBuffer->TailAsSpan(READ_BUFFER_SIZE);
uint32_t result;
size_t read;
size_t written;
bool hadErrors;
// Do not use structured binding lest deal with [-Werror=unused-variable]
std::tie(result, read, written, hadErrors) =
mUnicodeDecoder->DecodeToUTF16(src, dst, true);
if (!(mLookingForMetaCharset || mDecodingLocalFileWithoutTokenizing)) {
OnNewContent(dst.To(written));
}
if (hadErrors) {
mHasHadErrors = true;
}
MOZ_ASSERT(read == 0, "How come an empty span was read form?");
mLastBuffer->AdvanceEnd(written);
if (result == kOutputFull) {
RefPtr<nsHtml5OwningUTF16Buffer> newBuf =
nsHtml5OwningUTF16Buffer::FalliblyCreate(READ_BUFFER_SIZE);
if (!newBuf) {
MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
return;
}
mLastBuffer = (mLastBuffer->next = std::move(newBuf));
} else {
if (!mLookingForMetaCharset && mDecodingLocalFileWithoutTokenizing) {
MOZ_ASSERT(mNumBytesBuffered < LOCAL_FILE_UTF_8_BUFFER_SIZE);
MOZ_ASSERT(!mStartedFeedingDetector);
for (auto&& buffer : mBufferedBytes) {
FeedDetector(buffer);
}
MOZ_ASSERT(!mChardetEof);
DetectorEof();
auto [encoding, source] = GuessEncoding(true);
mCharsetSource = source;
if (encoding != mEncoding) {
mEncoding = encoding;
nsresult rv = ReDecodeLocalFile();
if (NS_FAILED(rv)) {
MarkAsBroken(rv);
return;
}
DoStopRequest();
return;
}
MOZ_ASSERT(mEncoding == UTF_8_ENCODING);
nsresult rv = CommitLocalFileToEncoding();
if (NS_FAILED(rv)) {
MarkAsBroken(rv);
return;
}
}
break;
}
}
mStreamState = STREAM_ENDED;
if (IsTerminatedOrInterrupted()) {
return;
}
ParseAvailableData();
}
class nsHtml5RequestStopper : public Runnable {
private:
nsHtml5StreamParserPtr mStreamParser;
public:
explicit nsHtml5RequestStopper(nsHtml5StreamParser* aStreamParser)
: Runnable("nsHtml5RequestStopper"), mStreamParser(aStreamParser) {}
NS_IMETHOD Run() override {
mozilla::MutexAutoLock autoLock(mStreamParser->mTokenizerMutex);
mStreamParser->DoStopRequest();
mStreamParser->PostLoadFlusher();
return NS_OK;
}
};
nsresult nsHtml5StreamParser::OnStopRequest(
nsIRequest* aRequest, nsresult status,
const mozilla::ReentrantMonitorAutoEnter& aProofOfLock) {
MOZ_ASSERT_IF(aRequest, mRequest == aRequest);
if (mOnStopCalled) {
// OnStopRequest already executed (probably OMT).
MOZ_ASSERT(NS_IsMainThread(), "Expected to run on main thread");
if (mOnDataFinishedTime) {
mOnStopRequestTime = TimeStamp::Now();
}
} else {
mOnStopCalled = true;
if (MOZ_UNLIKELY(NS_IsMainThread())) {
MOZ_ASSERT(mOnDataFinishedTime.IsNull(), "stale mOnDataFinishedTime");
nsCOMPtr<nsIRunnable> stopper = new nsHtml5RequestStopper(this);
if (NS_FAILED(
mEventTarget->Dispatch(stopper, nsIThread::DISPATCH_NORMAL))) {
NS_WARNING("Dispatching StopRequest event failed.");
}
} else {
if (StaticPrefs::network_send_OnDataFinished_html5parser()) {
MOZ_ASSERT(IsParserThread(), "Wrong thread!");
mOnDataFinishedTime = TimeStamp::Now();
mozilla::MutexAutoLock autoLock(mTokenizerMutex);
DoStopRequest();
PostLoadFlusher();
} else {
// Let the MainThread event handle this, even though it will just
// send it back to this thread, so we can accurately judge the impact
// of this change. This should eventually be removed
mOnStopCalled = false;
// don't record any telemetry for this
return NS_OK;
}
}
}
if (!mOnStopRequestTime.IsNull() && !mOnDataFinishedTime.IsNull()) {
TimeDuration delta = (mOnStopRequestTime - mOnDataFinishedTime);
MOZ_ASSERT((delta.ToMilliseconds() >= 0),
"OnDataFinished after OnStopRequest");
glean::networking::http_content_html5parser_ondatafinished_to_onstop_delay
.AccumulateRawDuration(delta);
}
return NS_OK;
}
void nsHtml5StreamParser::DoDataAvailableBuffer(
mozilla::Buffer<uint8_t>&& aBuffer) {
if (MOZ_UNLIKELY(!mBufferingBytes)) {
DoDataAvailable(aBuffer);
return;
}
if (MOZ_UNLIKELY(mLookingForXmlDeclarationForXmlViewSource)) {
const uint8_t* elements = aBuffer.Elements();
size_t length = aBuffer.Length();
const uint8_t* lt = (const uint8_t*)memchr(elements, '>', length);
if (!lt) {
mBufferedBytes.AppendElement(std::move(aBuffer));
return;
}
// We found an '>'. Now there either is or isn't an XML decl.
length = (lt - elements) + 1;
Vector<uint8_t> contiguous;
for (auto&& buffer : mBufferedBytes) {
if (!contiguous.append(buffer.Elements(), buffer.Length())) {
MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
return;
}
}
if (!contiguous.append(elements, length)) {
MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
return;
}
const Encoding* encoding =
xmldecl_parse(contiguous.begin(), contiguous.length());
if (encoding) {
mEncoding = WrapNotNull(encoding);
mCharsetSource = kCharsetFromXmlDeclaration;
}
mLookingForXmlDeclarationForXmlViewSource = false;
mBufferingBytes = false;
mUnicodeDecoder = mEncoding->NewDecoderWithoutBOMHandling();
mTreeBuilder->SetDocumentCharset(mEncoding, mCharsetSource, false);
for (auto&& buffer : mBufferedBytes) {
DoDataAvailable(buffer);
}
DoDataAvailable(aBuffer);
mBufferedBytes.Clear();
return;
}
CheckedInt<size_t> bufferedPlusLength(aBuffer.Length());
bufferedPlusLength += mNumBytesBuffered;
if (!bufferedPlusLength.isValid()) {
MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
return;
}
// Ensure that WriteStreamBytes() sees buffers ending
// exactly at the two special boundaries.
bool metaBoundaryWithinBuffer =
mLookingForMetaCharset &&
mNumBytesBuffered < UNCONDITIONAL_META_SCAN_BOUNDARY &&
bufferedPlusLength.value() > UNCONDITIONAL_META_SCAN_BOUNDARY;
bool localFileLimitWithinBuffer =
mDecodingLocalFileWithoutTokenizing &&
mNumBytesBuffered < LOCAL_FILE_UTF_8_BUFFER_SIZE &&
bufferedPlusLength.value() > LOCAL_FILE_UTF_8_BUFFER_SIZE;
if (!metaBoundaryWithinBuffer && !localFileLimitWithinBuffer) {
// Truncation OK, because we just checked the range.
mNumBytesBuffered = bufferedPlusLength.value();
mBufferedBytes.AppendElement(std::move(aBuffer));
DoDataAvailable(mBufferedBytes.LastElement());
} else {
MOZ_RELEASE_ASSERT(
!(metaBoundaryWithinBuffer && localFileLimitWithinBuffer),
"How can Necko give us a buffer this large?");
size_t boundary = metaBoundaryWithinBuffer
? UNCONDITIONAL_META_SCAN_BOUNDARY
: LOCAL_FILE_UTF_8_BUFFER_SIZE;
// Truncation OK, because the constant is small enough.
size_t overBoundary = bufferedPlusLength.value() - boundary;
MOZ_RELEASE_ASSERT(overBoundary < aBuffer.Length());
size_t untilBoundary = aBuffer.Length() - overBoundary;
auto span = aBuffer.AsSpan();
auto head = span.To(untilBoundary);
auto tail = span.From(untilBoundary);
MOZ_RELEASE_ASSERT(mNumBytesBuffered + untilBoundary == boundary);
// The following copies may end up being useless, but optimizing
// them away would add complexity.
Maybe<Buffer<uint8_t>> maybeHead = Buffer<uint8_t>::CopyFrom(head);
if (maybeHead.isNothing()) {
MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
return;
}
mNumBytesBuffered = boundary;
mBufferedBytes.AppendElement(std::move(*maybeHead));
DoDataAvailable(mBufferedBytes.LastElement());
// Re-decode may have happened here.
Maybe<Buffer<uint8_t>> maybeTail = Buffer<uint8_t>::CopyFrom(tail);
if (maybeTail.isNothing()) {
MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
return;
}
mNumBytesBuffered += tail.Length();
mBufferedBytes.AppendElement(std::move(*maybeTail));
DoDataAvailable(mBufferedBytes.LastElement());
}
// Do this clean-up here to avoid use-after-free when
// DoDataAvailable is passed a span pointing into an
// element of mBufferedBytes.
if (!mBufferingBytes) {
mBufferedBytes.Clear();
}
}
void nsHtml5StreamParser::DoDataAvailable(Span<const uint8_t> aBuffer) {
MOZ_ASSERT(IsParserThread(), "Wrong thread!");
MOZ_RELEASE_ASSERT(STREAM_BEING_READ == mStreamState,
"DoDataAvailable called when stream not open.");
mTokenizerMutex.AssertCurrentThreadOwns();
if (IsTerminated()) {
return;
}
nsresult rv;
if (HasDecoder()) {
if ((mForceAutoDetection || mCharsetSource < kCharsetFromParentFrame) &&
!mBufferingBytes && !mReparseForbidden &&
!(mMode == LOAD_AS_DATA || mMode == VIEW_SOURCE_XML)) {
MOZ_ASSERT(!mDecodingLocalFileWithoutTokenizing,
"How is mBufferingBytes false if "
"mDecodingLocalFileWithoutTokenizing is true?");
FeedDetector(aBuffer);
}
rv = WriteStreamBytes(aBuffer);
} else {
rv = SniffStreamBytes(aBuffer, false);
}
if (NS_FAILED(rv)) {
MarkAsBroken(rv);
return;
}
if (IsTerminatedOrInterrupted()) {
return;
}
if (!mLookingForMetaCharset && mDecodingLocalFileWithoutTokenizing) {
return;
}
ParseAvailableData();
if (mBomState != BOM_SNIFFING_OVER || mFlushTimerArmed || mSpeculating) {
return;
}
{
mozilla::MutexAutoLock flushTimerLock(mFlushTimerMutex);
mFlushTimer->InitWithNamedFuncCallback(
nsHtml5StreamParser::TimerCallback, static_cast<void*>(this),
mFlushTimerEverFired ? StaticPrefs::html5_flushtimer_initialdelay()
: StaticPrefs::html5_flushtimer_subsequentdelay(),
nsITimer::TYPE_ONE_SHOT, "nsHtml5StreamParser::DoDataAvailable");
}
mFlushTimerArmed = true;
}
class nsHtml5DataAvailable : public Runnable {
private:
nsHtml5StreamParserPtr mStreamParser;
Buffer<uint8_t> mData;
public:
nsHtml5DataAvailable(nsHtml5StreamParser* aStreamParser,
Buffer<uint8_t>&& aData)
: Runnable("nsHtml5DataAvailable"),
mStreamParser(aStreamParser),
mData(std::move(aData)) {}
NS_IMETHOD Run() override {
mozilla::MutexAutoLock autoLock(mStreamParser->mTokenizerMutex);
mStreamParser->DoDataAvailableBuffer(std::move(mData));
mStreamParser->PostLoadFlusher();
return NS_OK;
}
};
nsresult nsHtml5StreamParser::OnDataAvailable(nsIRequest* aRequest,
nsIInputStream* aInStream,
uint64_t aSourceOffset,
uint32_t aLength) {
nsresult rv;
MOZ_ASSERT(mRequest == aRequest, "Got data on wrong stream.");
uint32_t totalRead;
// Main thread to parser thread dispatch requires copying to buffer first.
if (MOZ_UNLIKELY(NS_IsMainThread())) {
if (NS_FAILED(rv = mExecutor->IsBroken())) {
return rv;
}
Maybe<Buffer<uint8_t>> maybe = Buffer<uint8_t>::Alloc(aLength);
if (maybe.isNothing()) {
return mExecutor->MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
}
Buffer<uint8_t> data(std::move(*maybe));
rv = aInStream->Read(reinterpret_cast<char*>(data.Elements()),
data.Length(), &totalRead);
NS_ENSURE_SUCCESS(rv, rv);
MOZ_ASSERT(totalRead == aLength);
nsCOMPtr<nsIRunnable> dataAvailable =
new nsHtml5DataAvailable(this, std::move(data));
if (NS_FAILED(mEventTarget->Dispatch(dataAvailable,
nsIThread::DISPATCH_NORMAL))) {
NS_WARNING("Dispatching DataAvailable event failed.");
}
return rv;
}
MOZ_ASSERT(IsParserThread(), "Wrong thread!");
mozilla::MutexAutoLock autoLock(mTokenizerMutex);
if (NS_FAILED(rv = mTreeBuilder->IsBroken())) {
return rv;
}
// Since we're getting OnDataAvailable directly on the parser thread,
// there is no nsHtml5DataAvailable that would call PostLoadFlusher.
// Hence, we need to call PostLoadFlusher() before this method returns.
// Braces for RAII clarity relative to the mutex despite not being
// strictly necessary.
{
auto speculationFlusher = MakeScopeExit([&] { PostLoadFlusher(); });
if (mBufferingBytes) {
Maybe<Buffer<uint8_t>> maybe = Buffer<uint8_t>::Alloc(aLength);
if (maybe.isNothing()) {
MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
return NS_ERROR_OUT_OF_MEMORY;
}
Buffer<uint8_t> data(std::move(*maybe));
rv = aInStream->Read(reinterpret_cast<char*>(data.Elements()),
data.Length(), &totalRead);
NS_ENSURE_SUCCESS(rv, rv);
MOZ_ASSERT(totalRead == aLength);
DoDataAvailableBuffer(std::move(data));
return rv;
}
// Read directly from response buffer.
rv = aInStream->ReadSegments(CopySegmentsToParser, this, aLength,
&totalRead);
NS_ENSURE_SUCCESS(rv, rv);
MOZ_ASSERT(totalRead == aLength);
return rv;
}
}
// Called under lock by function ptr
/* static */
nsresult nsHtml5StreamParser::CopySegmentsToParser(
nsIInputStream* aInStream, void* aClosure, const char* aFromSegment,
uint32_t aToOffset, uint32_t aCount,
uint32_t* aWriteCount) MOZ_NO_THREAD_SAFETY_ANALYSIS {
nsHtml5StreamParser* parser = static_cast<nsHtml5StreamParser*>(aClosure);
parser->DoDataAvailable(AsBytes(Span(aFromSegment, aCount)));
// Assume DoDataAvailable consumed all available bytes.
*aWriteCount = aCount;
return NS_OK;
}
const Encoding* nsHtml5StreamParser::PreferredForInternalEncodingDecl(
const nsAString& aEncoding) {
const Encoding* newEncoding = Encoding::ForLabel(aEncoding);
if (!newEncoding) {
// the encoding name is bogus
mTreeBuilder->MaybeComplainAboutCharset("EncMetaUnsupported", true,
mTokenizer->getLineNumber());
return nullptr;
}
if (newEncoding == UTF_16BE_ENCODING || newEncoding == UTF_16LE_ENCODING) {
mTreeBuilder->MaybeComplainAboutCharset("EncMetaUtf16", true,
mTokenizer->getLineNumber());
newEncoding = UTF_8_ENCODING;
}
if (newEncoding == X_USER_DEFINED_ENCODING) {
// WebKit/Blink hack for Indian and Armenian legacy sites
mTreeBuilder->MaybeComplainAboutCharset("EncMetaUserDefined", true,
mTokenizer->getLineNumber());
newEncoding = WINDOWS_1252_ENCODING;
}
if (newEncoding == REPLACEMENT_ENCODING) {
// No line number, because the replacement encoding doesn't allow
// showing the lines.
mTreeBuilder->MaybeComplainAboutCharset("EncMetaReplacement", true, 0);
}
return newEncoding;
}
bool nsHtml5StreamParser::internalEncodingDeclaration(nsHtml5String aEncoding) {
MOZ_ASSERT(IsParserThread(), "Wrong thread!");
if ((mCharsetSource >= kCharsetFromMetaTag &&
mCharsetSource != kCharsetFromFinalAutoDetectionFile) ||
mSeenEligibleMetaCharset) {
return false;
}
nsString newEncoding; // Not Auto, because using it to hold nsStringBuffer*
aEncoding.ToString(newEncoding);
auto encoding = PreferredForInternalEncodingDecl(newEncoding);
if (!encoding) {
return false;
}
mSeenEligibleMetaCharset = true;
if (!mLookingForMetaCharset) {
if (mInitialEncodingWasFromParentFrame) {
mTreeBuilder->MaybeComplainAboutCharset("EncMetaTooLateFrame", true,
mTokenizer->getLineNumber());
} else {
mTreeBuilder->MaybeComplainAboutCharset("EncMetaTooLate", true,
mTokenizer->getLineNumber());
}
return false;
}
if (mTemplatePushedOrHeadPopped) {
mTreeBuilder->MaybeComplainAboutCharset("EncMetaAfterHeadInKilobyte", false,
mTokenizer->getLineNumber());
}
if (mForceAutoDetection &&
(encoding->IsAsciiCompatible() || encoding == ISO_2022_JP_ENCODING)) {
return false;
}
mNeedsEncodingSwitchTo = encoding;
mEncodingSwitchSource = kCharsetFromMetaTag;
return true;
}
bool nsHtml5StreamParser::TemplatePushedOrHeadPopped() {
MOZ_ASSERT(
IsParserThread() || mMode == PLAIN_TEXT || mMode == VIEW_SOURCE_PLAIN,
"Wrong thread!");
mTemplatePushedOrHeadPopped = true;
return mNumBytesBuffered >= UNCONDITIONAL_META_SCAN_BOUNDARY;
}
void nsHtml5StreamParser::RememberGt(int32_t aPos) {
if (mLookingForMetaCharset) {
mGtBuffer = mFirstBuffer;
mGtPos = aPos;
}
}
void nsHtml5StreamParser::PostLoadFlusher() {
MOZ_ASSERT(IsParserThread(), "Wrong thread!");
mTokenizerMutex.AssertCurrentThreadOwns();
mTreeBuilder->FlushLoads();
// Dispatch this runnable unconditionally, because the loads
// that need flushing may have been flushed earlier even if the
// flush right above here did nothing. (Is this still true?)
nsCOMPtr<nsIRunnable> runnable(mLoadFlusher);
if (NS_FAILED(
DispatchToMain(CreateRenderBlockingRunnable(runnable.forget())))) {
NS_WARNING("failed to dispatch load flush event");
}
if ((mMode == VIEW_SOURCE_HTML || mMode == VIEW_SOURCE_XML) &&
mTokenizer->ShouldFlushViewSource()) {
auto r = mTreeBuilder->Flush(); // delete useless ops
MOZ_ASSERT(r.isOk(), "Should have null sink with View Source");
r = mTokenizer->FlushViewSource();
if (r.isErr()) {
MarkAsBroken(r.unwrapErr());
return;
}
if (r.unwrap()) {
nsCOMPtr<nsIRunnable> runnable(mExecutorFlusher);
if (NS_FAILED(DispatchToMain(runnable.forget()))) {
NS_WARNING("failed to dispatch executor flush event");
}
}
}
}
void nsHtml5StreamParser::FlushTreeOpsAndDisarmTimer() {
MOZ_ASSERT(IsParserThread(), "Wrong thread!");
if (mFlushTimerArmed) {
// avoid calling Cancel if the flush timer isn't armed to avoid acquiring
// a mutex
{
mozilla::MutexAutoLock flushTimerLock(mFlushTimerMutex);
mFlushTimer->Cancel();
}
mFlushTimerArmed = false;
}
if (mMode == VIEW_SOURCE_HTML || mMode == VIEW_SOURCE_XML) {
auto r = mTokenizer->FlushViewSource();
if (r.isErr()) {
MarkAsBroken(r.unwrapErr());
}
}
auto r = mTreeBuilder->Flush();
if (r.isErr()) {
MarkAsBroken(r.unwrapErr());
}
nsCOMPtr<nsIRunnable> runnable(mExecutorFlusher);
if (NS_FAILED(DispatchToMain(runnable.forget()))) {
NS_WARNING("failed to dispatch executor flush event");
}
}
void nsHtml5StreamParser::SwitchDecoderIfAsciiSoFar(
NotNull<const Encoding*> aEncoding) {
if (mEncoding == aEncoding) {
MOZ_ASSERT(!mStartedFeedingDevTools);
// Report all already-decoded buffers to the dev tools if needed.
if (mURIToSendToDevtools) {
nsHtml5OwningUTF16Buffer* buffer = mFirstBufferOfMetaScan;
while (buffer) {
auto s = Span(buffer->getBuffer(), buffer->getEnd());
OnNewContent(s);
buffer = buffer->next;
}
}
return;
}
if (!mEncoding->IsAsciiCompatible() || !aEncoding->IsAsciiCompatible()) {
return;
}
size_t numAscii = 0;
MOZ_ASSERT(mFirstBufferOfMetaScan,
"Why did we come here without starting meta scan?");
nsHtml5OwningUTF16Buffer* buffer = mFirstBufferOfMetaScan;
while (buffer != mFirstBuffer) {
MOZ_ASSERT(buffer, "mFirstBuffer should have acted as sentinel!");
MOZ_ASSERT(buffer->getStart() == buffer->getEnd(),
"Why wasn't an early buffer fully consumed?");
auto s = Span(buffer->getBuffer(), buffer->getStart());
if (!IsAscii(s)) {
return;
}
numAscii += s.Length();
buffer = buffer->next;
}
auto s = Span(mFirstBuffer->getBuffer(), mFirstBuffer->getStart());
if (!IsAscii(s)) {
return;
}
numAscii += s.Length();
MOZ_ASSERT(!mStartedFeedingDevTools);
// Report the ASCII prefix to dev tools if needed
if (mURIToSendToDevtools) {
buffer = mFirstBufferOfMetaScan;
while (buffer != mFirstBuffer) {
MOZ_ASSERT(buffer, "mFirstBuffer should have acted as sentinel!");
MOZ_ASSERT(buffer->getStart() == buffer->getEnd(),
"Why wasn't an early buffer fully consumed?");
auto s = Span(buffer->getBuffer(), buffer->getStart());
OnNewContent(s);
buffer = buffer->next;
}
auto s = Span(mFirstBuffer->getBuffer(), mFirstBuffer->getStart());
OnNewContent(s);
}
// Success! Now let's get rid of the already-decoded but not tokenized data:
mFirstBuffer->setEnd(mFirstBuffer->getStart());
mLastBuffer = mFirstBuffer;
mFirstBuffer->next = nullptr;
// Note: We could have scanned further for ASCII, which could avoid some
// buffer deallocation and reallocation. However, chances are that if we got
// until meta without non-ASCII before, there's going to be a title with
// non-ASCII soon after anyway, so let's avoid the complexity of finding out.
MOZ_ASSERT(mUnicodeDecoder, "How come we scanned meta without a decoder?");
mEncoding = aEncoding;
mEncoding->NewDecoderWithoutBOMHandlingInto(*mUnicodeDecoder);
mHasHadErrors = false;
MOZ_ASSERT(!mDecodingLocalFileWithoutTokenizing,
"Must have set mDecodingLocalFileWithoutTokenizing to false to "
"report data to dev tools below");
MOZ_ASSERT(!mLookingForMetaCharset,
"Must have set mLookingForMetaCharset to false to report data to "
"dev tools below");
// Now skip over as many bytes and redecode the tail of the
// buffered bytes.
size_t skipped = 0;
for (auto&& buffer : mBufferedBytes) {
size_t nextSkipped = skipped + buffer.Length();
if (nextSkipped <= numAscii) {
skipped = nextSkipped;
continue;
}
if (skipped >= numAscii) {
WriteStreamBytes(buffer);
skipped = nextSkipped;
continue;
}
size_t tailLength = nextSkipped - numAscii;
WriteStreamBytes(Span<uint8_t>(buffer).From(buffer.Length() - tailLength));
skipped = nextSkipped;
}
}
size_t nsHtml5StreamParser::CountGts() {
if (!mGtBuffer) {
return 0;
}
size_t gts = 0;
nsHtml5OwningUTF16Buffer* buffer = mFirstBufferOfMetaScan;
for (;;) {
MOZ_ASSERT(buffer, "How did we walk past mGtBuffer?");
char16_t* buf = buffer->getBuffer();
if (buffer == mGtBuffer) {
for (int32_t i = 0; i <= mGtPos; ++i) {
if (buf[i] == u'>') {
++gts;
}
}
break;
}
for (int32_t i = 0; i < buffer->getEnd(); ++i) {
if (buf[i] == u'>') {
++gts;
}
}
buffer = buffer->next;
}
return gts;
}
void nsHtml5StreamParser::DiscardMetaSpeculation() {
mozilla::MutexAutoLock speculationAutoLock(mSpeculationMutex);
// Rewind the stream
MOZ_ASSERT(!mAtEOF, "How did we end up setting this?");
mTokenizer->resetToDataState();
mTokenizer->setLineNumber(1);
mLastWasCR = false;
if (mMode == PLAIN_TEXT || mMode == VIEW_SOURCE_PLAIN) {
// resetToDataState() above logically rewinds to the state before
// the plain text start, so we need to start plain text again to
// put the tokenizer into the plain text state.
mTokenizer->StartPlainText();
}
mFirstBuffer = mLastBuffer;
mFirstBuffer->setStart(0);
mFirstBuffer->setEnd(0);
mFirstBuffer->next = nullptr;
mTreeBuilder->flushCharacters(); // empty the pending buffer
mTreeBuilder->ClearOps(); // now get rid of the failed ops
if (mMode == VIEW_SOURCE_HTML) {
mTokenizer->RewindViewSource();
}
{
// We know that this resets the tree builder back to the start state.
// This must happen _after_ the flushCharacters() call above!
const auto& speculation = mSpeculations.ElementAt(0);
mTreeBuilder->loadState(speculation->GetSnapshot());
}
// Experimentation suggests that we don't need to do anything special
// for ignoring the leading LF in View Source here.
mSpeculations.Clear(); // potentially a huge number of destructors
// run here synchronously...
// Now set up a new speculation for the main thread to find.
// Note that we stay in the speculating state, because the main thread
// knows how to come out of that state and this thread does not.
nsHtml5Speculation* speculation = new nsHtml5Speculation(
mFirstBuffer, mFirstBuffer->getStart(), mTokenizer->getLineNumber(),
mTokenizer->getColumnNumber(), mTreeBuilder->newSnapshot());
MOZ_ASSERT(!mFlushTimerArmed, "How did we end up arming the timer?");
if (mMode == VIEW_SOURCE_HTML) {
mTokenizer->SetViewSourceOpSink(speculation);
mTokenizer->StartViewSourceCharacters();
} else {
MOZ_ASSERT(mMode != VIEW_SOURCE_XML);
mTreeBuilder->SetOpSink(speculation);
}
mSpeculations.AppendElement(speculation); // adopts the pointer
MOZ_ASSERT(mSpeculating, "How did we end speculating?");
}
/*
* The general idea is to match WebKit and Blink exactly for meta
* scan except:
*
* 1. WebKit and Blink look for meta as if scripting was disabled
* for `noscript` purposes. This implementation matches the
* `noscript` treatment of the observable DOM building (in order
* to be able to use the same tree builder run).
* 2. WebKit and Blink look for meta as if the foreign content
* feedback from the tree builder to the tokenizer didn't exist.
* This implementation considers the foreign content rules in
* order to be able to use the same tree builder run for meta
* and the observable DOM building. Note that since <svg> and
* <math> imply the end of head, this only matters for meta after
* head but starting within the 1024-byte zone.
*
* Template is treated specially, because that WebKit/Blink behavior
* is easy to emulate unlike the above two exceptions. In general,
* the meta scan token handler in WebKit and Blink behaves as if there
* was a scripting-disabled tree builder predating the introduction
* of foreign content and template.
*
* Meta is honored if it _starts_ within the first 1024 kilobytes or,
* if by the 1024-byte boundary head hasn't ended and a template
* element hasn't started, a meta occurs before the first of the head
* ending or a template element starting.
*
* If a meta isn't honored according to the above definition, and
* we aren't dealing with plain text, the buffered bytes, which by
* now have to contain `>` character unless we encountered EOF, are
* scanned for syntax resembling an XML declaration.
*
* If neither a meta nor syntax resembling an XML declaration has
* been honored and we aren't inheriting the encoding from a
* same-origin parent or parsing for XHR, chardetng is used.
* chardetng runs first for the part of the document that was searched
* for meta and then at EOF. The part searched for meta is defined as
* follows in order to avoid network buffer boundary-dependent
* behavior:
*
* 1. At least the first 1024 bytes. (This is what happens for plain
* text.)
* 2. If the 1024-byte boundary is within a tag, comment, doctype,
* or CDATA section, at least up to the end of that token or CDATA
* section. (Exception: If the 1024-byte boundary is in an RCDATA
* end tag that hasn't yet been decided to be an end tag, the
* token is not considered.)
* 3. If at the 1024-byte boundary, head hasn't ended and there hasn't
* been a template tag, up to the end of the first template tag
* or token ending the head, whichever comes first.
* 4. Except if head is ended by a text token, only to the end of the
* most recent tag, comment, or doctype token. (Because text is
* coalesced, so it would be harder to correlate the text to the
* bytes.)
*
* An encoding-related reload is still possible if chardetng's guess
* at EOF differs from its initial guess.
*/
bool nsHtml5StreamParser::ProcessLookingForMetaCharset(bool aEof) {
MOZ_ASSERT(mBomState == BOM_SNIFFING_OVER);
MOZ_ASSERT(mMode != VIEW_SOURCE_XML);
bool rewound = false;
MOZ_ASSERT(mForceAutoDetection ||
mCharsetSource < kCharsetFromInitialAutoDetectionASCII ||
mCharsetSource == kCharsetFromParentFrame,
"Why are we looking for meta charset if we've seen it?");
// NOTE! We may come here multiple times with
// mNumBytesBuffered == UNCONDITIONAL_META_SCAN_BOUNDARY
// if the tokenizer suspends multiple times after decoding has reached
// mNumBytesBuffered == UNCONDITIONAL_META_SCAN_BOUNDARY. That's why
// we need to also check whether the we are at the end of the last
// decoded buffer.
// Note that DoDataAvailableBuffer() ensures that the code here has
// the opportunity to run at the exact UNCONDITIONAL_META_SCAN_BOUNDARY
// even if there isn't a network buffer boundary there.
bool atKilobyte = false;
if ((mNumBytesBuffered == UNCONDITIONAL_META_SCAN_BOUNDARY &&
mFirstBuffer == mLastBuffer && !mFirstBuffer->hasMore())) {
atKilobyte = true;
mTokenizer->AtKilobyteBoundary();
}
if (!mNeedsEncodingSwitchTo &&
(aEof || (mTemplatePushedOrHeadPopped &&
!mTokenizer->IsInTokenStartedAtKilobyteBoundary() &&
(atKilobyte ||
mNumBytesBuffered > UNCONDITIONAL_META_SCAN_BOUNDARY)))) {
// meta charset was not found
mLookingForMetaCharset = false;
if (mStartsWithLtQuestion && mCharsetSource < kCharsetFromXmlDeclaration) {
// Look for bogo XML declaration.
// Search the first buffer in the hope that '>' is within it.
MOZ_ASSERT(!mBufferedBytes.IsEmpty(),
"How did at least <? not get buffered?");
Buffer<uint8_t>& first = mBufferedBytes[0];
const Encoding* encoding =
xmldecl_parse(first.Elements(), first.Length());
if (!encoding) {
// Our bogo XML declaration scanner wants to see a contiguous buffer, so
// let's linearize the data. (Ideally, the XML declaration scanner would
// be incremental, but this is the rare path anyway.)
Vector<uint8_t> contiguous;
if (!contiguous.append(first.Elements(), first.Length())) {
MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
return false;
}
for (size_t i = 1; i < mBufferedBytes.Length(); ++i) {
Buffer<uint8_t>& buffer = mBufferedBytes[i];
const uint8_t* elements = buffer.Elements();
size_t length = buffer.Length();
const uint8_t* lt = (const uint8_t*)memchr(elements, '>', length);
bool stop = false;
if (lt) {
length = (lt - elements) + 1;
stop = true;
}
if (!contiguous.append(elements, length)) {
MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
return false;
}
if (stop) {
// Avoid linearizing all buffered bytes unnecessarily.
break;
}
}
encoding = xmldecl_parse(contiguous.begin(), contiguous.length());
}
if (encoding) {
if (!(mForceAutoDetection && (encoding->IsAsciiCompatible() ||
encoding == ISO_2022_JP_ENCODING))) {
mForceAutoDetection = false;
mNeedsEncodingSwitchTo = encoding;
mEncodingSwitchSource = kCharsetFromXmlDeclaration;
}
}
}
// Check again in case we found an encoding in the bogo XML declaration.
if (!mNeedsEncodingSwitchTo &&
(mForceAutoDetection ||
mCharsetSource < kCharsetFromInitialAutoDetectionASCII) &&
!(mMode == LOAD_AS_DATA || mMode == VIEW_SOURCE_XML) &&
!(mDecodingLocalFileWithoutTokenizing && !aEof &&
mNumBytesBuffered <= LOCAL_FILE_UTF_8_BUFFER_SIZE)) {
MOZ_ASSERT(!mStartedFeedingDetector);
if (mNumBytesBuffered == UNCONDITIONAL_META_SCAN_BOUNDARY || aEof) {
// We know that all the buffered bytes have been tokenized, so feed
// them all to chardetng.
for (auto&& buffer : mBufferedBytes) {
FeedDetector(buffer);
}
if (aEof) {
MOZ_ASSERT(!mChardetEof);
DetectorEof();
}
auto [encoding, source] = GuessEncoding(true);
mNeedsEncodingSwitchTo = encoding;
mEncodingSwitchSource = source;
} else if (mNumBytesBuffered > UNCONDITIONAL_META_SCAN_BOUNDARY) {
size_t gtsLeftToFind = CountGts();
size_t bytesSeen = 0;
// We sync the bytes to the UTF-16 code units seen to avoid depending
// on network buffer boundaries. We do the syncing by counting '>'
// bytes / code units. However, we always scan at least 1024 bytes.
// The 1024-byte boundary is guaranteed to be between buffers.
// The guarantee is implemented in DoDataAvailableBuffer().
for (auto&& buffer : mBufferedBytes) {
if (!mNeedsEncodingSwitchTo) {
if (gtsLeftToFind) {
auto span = buffer.AsSpan();
bool feed = true;
for (size_t i = 0; i < span.Length(); ++i) {
if (span[i] == uint8_t('>')) {
--gtsLeftToFind;
if (!gtsLeftToFind) {
if (bytesSeen < UNCONDITIONAL_META_SCAN_BOUNDARY) {
break;
}
++i; // Skip the gt
FeedDetector(span.To(i));
auto [encoding, source] = GuessEncoding(true);
mNeedsEncodingSwitchTo = encoding;
mEncodingSwitchSource = source;
FeedDetector(span.From(i));
bytesSeen += buffer.Length();
// No need to update bytesSeen anymore, but let's do it for
// debugging.
// We should do `continue outer;` but C++ can't.
feed = false;
break;
}
}
}
if (feed) {
FeedDetector(buffer);
bytesSeen += buffer.Length();
}
continue;
}
if (bytesSeen == UNCONDITIONAL_META_SCAN_BOUNDARY) {
auto [encoding, source] = GuessEncoding(true);
mNeedsEncodingSwitchTo = encoding;
mEncodingSwitchSource = source;
}
}
FeedDetector(buffer);
bytesSeen += buffer.Length();
}
}
MOZ_ASSERT(mNeedsEncodingSwitchTo,
"How come we didn't call GuessEncoding()?");
}
}
if (mNeedsEncodingSwitchTo) {
mDecodingLocalFileWithoutTokenizing = false;
mLookingForMetaCharset = false;
auto needsEncodingSwitchTo = WrapNotNull(mNeedsEncodingSwitchTo);
mNeedsEncodingSwitchTo = nullptr;
SwitchDecoderIfAsciiSoFar(needsEncodingSwitchTo);
// The above line may have changed mEncoding so that mEncoding equals
// needsEncodingSwitchTo.
mCharsetSource = mEncodingSwitchSource;
if (mMode == VIEW_SOURCE_HTML) {
auto r = mTokenizer->FlushViewSource();
if (r.isErr()) {
MarkAsBroken(r.unwrapErr());
return false;
}
}
auto r = mTreeBuilder->Flush();
if (r.isErr()) {
MarkAsBroken(r.unwrapErr());
return false;
}
if (mEncoding != needsEncodingSwitchTo) {
// Speculation failed
rewound = true;
if (mEncoding == ISO_2022_JP_ENCODING ||
needsEncodingSwitchTo == ISO_2022_JP_ENCODING) {
// Chances are no Web author will fix anything due to this message, so
// this is here to help understanding issues when debugging sites made
// by someone else.
mTreeBuilder->MaybeComplainAboutCharset("EncSpeculationFail2022", false,
mTokenizer->getLineNumber());
} else {
if (mCharsetSource == kCharsetFromMetaTag) {
mTreeBuilder->MaybeComplainAboutCharset(
"EncSpeculationFailMeta", false, mTokenizer->getLineNumber());
} else if (mCharsetSource == kCharsetFromXmlDeclaration) {
// This intentionally refers to the line number of how far ahead
// the document was parsed even though the bogo XML decl is always
// on line 1.
mTreeBuilder->MaybeComplainAboutCharset(
"EncSpeculationFailXml", false, mTokenizer->getLineNumber());
}
}
DiscardMetaSpeculation();
// Redecode the stream.
mEncoding = needsEncodingSwitchTo;
mUnicodeDecoder = mEncoding->NewDecoderWithBOMRemoval();
mHasHadErrors = false;
MOZ_ASSERT(!mDecodingLocalFileWithoutTokenizing,
"Must have set mDecodingLocalFileWithoutTokenizing to false "
"to report data to dev tools below");
MOZ_ASSERT(!mLookingForMetaCharset,
"Must have set mLookingForMetaCharset to false to report data "
"to dev tools below");
for (auto&& buffer : mBufferedBytes) {
nsresult rv = WriteStreamBytes(buffer);
if (NS_FAILED(rv)) {
MarkAsBroken(rv);
return false;
}
}
}
} else if (!mLookingForMetaCharset && !mDecodingLocalFileWithoutTokenizing) {
MOZ_ASSERT(!mStartedFeedingDevTools);
// Report all already-decoded buffers to the dev tools if needed.
if (mURIToSendToDevtools) {
nsHtml5OwningUTF16Buffer* buffer = mFirstBufferOfMetaScan;
while (buffer) {
auto s = Span(buffer->getBuffer(), buffer->getEnd());
OnNewContent(s);
buffer = buffer->next;
}
}
}
if (!mLookingForMetaCharset) {
mGtBuffer = nullptr;
mGtPos = 0;
if (!mDecodingLocalFileWithoutTokenizing) {
mFirstBufferOfMetaScan = nullptr;
mBufferingBytes = false;
mBufferedBytes.Clear();
mTreeBuilder->SetDocumentCharset(mEncoding, mCharsetSource, true);
if (mMode == VIEW_SOURCE_HTML) {
auto r = mTokenizer->FlushViewSource();
if (r.isErr()) {
MarkAsBroken(r.unwrapErr());
return false;
}
}
auto r = mTreeBuilder->Flush();
if (r.isErr()) {
MarkAsBroken(r.unwrapErr());
return false;
}
}
}
return rewound;
}
void nsHtml5StreamParser::ParseAvailableData() {
MOZ_ASSERT(IsParserThread(), "Wrong thread!");
mTokenizerMutex.AssertCurrentThreadOwns();
MOZ_ASSERT(!(mDecodingLocalFileWithoutTokenizing && !mLookingForMetaCharset));
if (IsTerminatedOrInterrupted()) {
return;
}
if (mSpeculating && !IsSpeculationEnabled()) {
return;
}
bool requestedReload = false;
for (;;) {
if (!mFirstBuffer->hasMore()) {
if (mFirstBuffer == mLastBuffer) {
switch (mStreamState) {
case STREAM_BEING_READ:
// never release the last buffer.
if (!mSpeculating) {
// reuse buffer space if not speculating
mFirstBuffer->setStart(0);
mFirstBuffer->setEnd(0);
}
return; // no more data for now but expecting more
case STREAM_ENDED:
if (mAtEOF) {
return;
}
if (mLookingForMetaCharset) {
// When called with aEof=true, ProcessLookingForMetaCharset()
// is guaranteed to set mLookingForMetaCharset to false so
// that we can't come here twice.
if (ProcessLookingForMetaCharset(true)) {
if (IsTerminatedOrInterrupted()) {
return;
}
continue;
}
} else if ((mForceAutoDetection ||
mCharsetSource < kCharsetFromParentFrame) &&
!(mMode == LOAD_AS_DATA || mMode == VIEW_SOURCE_XML) &&
!mReparseForbidden) {
// An earlier DetectorEof() call is possible in which case
// the one here is a no-op.
DetectorEof();
auto [encoding, source] = GuessEncoding(false);
if (encoding != mEncoding) {
// Request a reload from the docshell.
MOZ_ASSERT(
(source >=
kCharsetFromFinalAutoDetectionWouldHaveBeenUTF8InitialWasASCII &&
source <=
kCharsetFromFinalAutoDetectionWouldNotHaveBeenUTF8DependedOnTLDInitialWasASCII) ||
source == kCharsetFromFinalUserForcedAutoDetection);
mTreeBuilder->NeedsCharsetSwitchTo(encoding, source, 0);
requestedReload = true;
} else if (mCharsetSource ==
kCharsetFromInitialAutoDetectionASCII &&
mDetectorHasSeenNonAscii) {
mCharsetSource = source;
mTreeBuilder->UpdateCharsetSource(mCharsetSource);
}
}
mAtEOF = true;
if (!mForceAutoDetection && !requestedReload) {
if (mCharsetSource == kCharsetFromParentFrame) {
mTreeBuilder->MaybeComplainAboutCharset("EncNoDeclarationFrame",
false, 0);
} else if (mCharsetSource == kCharsetFromXmlDeclaration) {
// We know the bogo XML decl is always on the first line.
mTreeBuilder->MaybeComplainAboutCharset("EncXmlDecl", false, 1);
} else if (
mCharsetSource >=
kCharsetFromInitialAutoDetectionWouldHaveBeenUTF8 &&
mCharsetSource <=
kCharsetFromInitialAutoDetectionWouldNotHaveBeenUTF8DependedOnTLD) {
if (mMode == PLAIN_TEXT || mMode == VIEW_SOURCE_PLAIN) {
mTreeBuilder->MaybeComplainAboutCharset("EncNoDeclPlain",
true, 0);
} else {
mTreeBuilder->MaybeComplainAboutCharset("EncNoDecl", true, 0);
}
}
if (mHasHadErrors && mEncoding != REPLACEMENT_ENCODING) {
if (mEncoding == UTF_8_ENCODING) {
mTreeBuilder->TryToEnableEncodingMenu();
}
if (mCharsetSource == kCharsetFromParentFrame) {
if (mMode == PLAIN_TEXT || mMode == VIEW_SOURCE_PLAIN) {
mTreeBuilder->MaybeComplainAboutCharset(
"EncErrorFramePlain", true, 0);
} else {
mTreeBuilder->MaybeComplainAboutCharset("EncErrorFrame",
true, 0);
}
} else if (
mCharsetSource >= kCharsetFromXmlDeclaration &&
!(mCharsetSource >=
kCharsetFromFinalAutoDetectionWouldHaveBeenUTF8InitialWasASCII &&
mCharsetSource <=
kCharsetFromFinalUserForcedAutoDetection)) {
mTreeBuilder->MaybeComplainAboutCharset("EncError", true, 0);
}
}
}
if (NS_SUCCEEDED(mTreeBuilder->IsBroken())) {
mTokenizer->eof();
nsresult rv;
if (NS_FAILED((rv = mTreeBuilder->IsBroken()))) {
MarkAsBroken(rv);
} else {
mTreeBuilder->StreamEnded();
if (mMode == VIEW_SOURCE_HTML || mMode == VIEW_SOURCE_XML) {
if (!mTokenizer->EndViewSource()) {
MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
}
}
}
}
FlushTreeOpsAndDisarmTimer();
return; // no more data and not expecting more
default:
MOZ_ASSERT_UNREACHABLE("It should be impossible to reach this.");
return;
}
}
mFirstBuffer = mFirstBuffer->next;
continue;
}
// now we have a non-empty buffer
mFirstBuffer->adjust(mLastWasCR);
mLastWasCR = false;
if (mFirstBuffer->hasMore()) {
if (!mTokenizer->EnsureBufferSpace(mFirstBuffer->getLength())) {
MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
return;
}
mLastWasCR = mTokenizer->tokenizeBuffer(mFirstBuffer);
nsresult rv;
if (NS_FAILED((rv = mTreeBuilder->IsBroken()))) {
MarkAsBroken(rv);
return;
}
if (mTreeBuilder->HasScriptThatMayDocumentWriteOrBlock()) {
// `HasScriptThatMayDocumentWriteOrBlock()` cannot return true if the
// tree builder is preventing script execution.
MOZ_ASSERT(mMode == NORMAL);
mozilla::MutexAutoLock speculationAutoLock(mSpeculationMutex);
nsHtml5Speculation* speculation = new nsHtml5Speculation(
mFirstBuffer, mFirstBuffer->getStart(), mTokenizer->getLineNumber(),
mTokenizer->getColumnNumber(), mTreeBuilder->newSnapshot());
mTreeBuilder->AddSnapshotToScript(speculation->GetSnapshot(),
speculation->GetStartLineNumber());
if (mLookingForMetaCharset) {
if (mMode == VIEW_SOURCE_HTML) {
auto r = mTokenizer->FlushViewSource();
if (r.isErr()) {
MarkAsBroken(r.unwrapErr());
return;
}
}
auto r = mTreeBuilder->Flush();
if (r.isErr()) {
MarkAsBroken(r.unwrapErr());
return;
}
} else {
FlushTreeOpsAndDisarmTimer();
}
mTreeBuilder->SetOpSink(speculation);
mSpeculations.AppendElement(speculation); // adopts the pointer
mSpeculating = true;
}
if (IsTerminatedOrInterrupted()) {
return;
}
}
if (mLookingForMetaCharset) {
Unused << ProcessLookingForMetaCharset(false);
}
}
}
class nsHtml5StreamParserContinuation : public Runnable {
private:
nsHtml5StreamParserPtr mStreamParser;
public:
explicit nsHtml5StreamParserContinuation(nsHtml5StreamParser* aStreamParser)
: Runnable("nsHtml5StreamParserContinuation"),
mStreamParser(aStreamParser) {}
NS_IMETHOD Run() override {
mozilla::MutexAutoLock autoLock(mStreamParser->mTokenizerMutex);
mStreamParser->Uninterrupt();
mStreamParser->ParseAvailableData();
return NS_OK;
}
};
void nsHtml5StreamParser::ContinueAfterScriptsOrEncodingCommitment(
nsHtml5Tokenizer* aTokenizer, nsHtml5TreeBuilder* aTreeBuilder,
bool aLastWasCR) {
// nullptr for aTokenizer means encoding commitment as opposed to the "after
// scripts" case.
MOZ_ASSERT(NS_IsMainThread(), "Wrong thread!");
MOZ_ASSERT(mMode != VIEW_SOURCE_XML,
"ContinueAfterScriptsOrEncodingCommitment called in XML view "
"source mode!");
MOZ_ASSERT(!(aTokenizer && mMode == VIEW_SOURCE_HTML),
"ContinueAfterScriptsOrEncodingCommitment called with non-null "
"tokenizer in HTML view "
"source mode.");
if (NS_FAILED(mExecutor->IsBroken())) {
return;
}
MOZ_ASSERT(!(aTokenizer && mMode != NORMAL),
"We should only be executing scripts in the normal mode.");
if (!aTokenizer && (mMode == PLAIN_TEXT || mMode == VIEW_SOURCE_PLAIN ||
mMode == VIEW_SOURCE_HTML)) {
// Take the ops that were generated from OnStartRequest for the synthetic
// head section of the document for plain text and HTML View Source.
// XML View Source never needs this kind of encoding commitment.
// We need to take the ops here so that they end up in the queue before
// the ops that we take from a speculation later in this method.
if (!mExecutor->TakeOpsFromStage()) {
mExecutor->MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
return;
}
} else {
#ifdef DEBUG
mExecutor->AssertStageEmpty();
#endif
}
bool speculationFailed = false;
{
mozilla::MutexAutoLock speculationAutoLock(mSpeculationMutex);
if (mSpeculations.IsEmpty()) {
MOZ_ASSERT_UNREACHABLE(
"ContinueAfterScriptsOrEncodingCommitment called without "
"speculations.");
return;
}
const auto& speculation = mSpeculations.ElementAt(0);
if (aTokenizer &&
(aLastWasCR || !aTokenizer->isInDataState() ||
!aTreeBuilder->snapshotMatches(speculation->GetSnapshot()))) {
speculationFailed = true;
// We've got a failed speculation :-(
MaybeDisableFutureSpeculation();
Interrupt(); // Make the parser thread release the tokenizer mutex sooner
// Note that the interrupted state continues across possible intervening
// Necko events until the nsHtml5StreamParserContinuation posted at the
// end of this method runs. Therefore, this thread is guaranteed to
// acquire mTokenizerMutex soon even if an intervening Necko event grabbed
// it between now and the acquisition below.
// now fall out of the speculationAutoLock into the tokenizerAutoLock
// block
} else {
// We've got a successful speculation!
if (mSpeculations.Length() > 1) {
// the first speculation isn't the current speculation, so there's
// no need to bother the parser thread.
if (!speculation->FlushToSink(mExecutor)) {
mExecutor->MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
return;
}
MOZ_ASSERT(!mExecutor->IsScriptExecuting(),
"ParseUntilBlocked() was supposed to ensure we don't come "
"here when scripts are executing.");
MOZ_ASSERT(!aTokenizer || mExecutor->IsInFlushLoop(),
"How are we here if "
"RunFlushLoop() didn't call ParseUntilBlocked() or we're "
"not committing to an encoding?");
mSpeculations.RemoveElementAt(0);
return;
}
// else
Interrupt(); // Make the parser thread release the tokenizer mutex sooner
// Note that the interrupted state continues across possible intervening
// Necko events until the nsHtml5StreamParserContinuation posted at the
// end of this method runs. Therefore, this thread is guaranteed to
// acquire mTokenizerMutex soon even if an intervening Necko event grabbed
// it between now and the acquisition below.
// now fall through
// the first speculation is the current speculation. Need to
// release the the speculation mutex and acquire the tokenizer
// mutex. (Just acquiring the other mutex here would deadlock)
}
}
{
mozilla::MutexAutoLock tokenizerAutoLock(mTokenizerMutex);
#ifdef DEBUG
{
mAtomTable.SetPermittedLookupEventTarget(
GetMainThreadSerialEventTarget());
}
#endif
// In principle, the speculation mutex should be acquired here,
// but there's no point, because the parser thread only acquires it
// when it has also acquired the tokenizer mutex and we are already
// holding the tokenizer mutex.
if (speculationFailed) {
MOZ_ASSERT(mMode == NORMAL);
// Rewind the stream
mAtEOF = false;
const auto& speculation = mSpeculations.ElementAt(0);
mFirstBuffer = speculation->GetBuffer();
mFirstBuffer->setStart(speculation->GetStart());
mTokenizer->setLineNumber(speculation->GetStartLineNumber());
mTokenizer->setColumnNumberAndResetNextLine(
speculation->GetStartColumnNumber());
nsContentUtils::ReportToConsole(
nsIScriptError::warningFlag, "DOM Events"_ns,
mExecutor->GetDocument(), nsContentUtils::eDOM_PROPERTIES,
"SpeculationFailed2", nsTArray<nsString>(), nullptr, u""_ns,
speculation->GetStartLineNumber(),
speculation->GetStartColumnNumber());
nsHtml5OwningUTF16Buffer* buffer = mFirstBuffer->next;
while (buffer) {
buffer->setStart(0);
buffer = buffer->next;
}
mSpeculations.Clear(); // potentially a huge number of destructors
// run here synchronously on the main thread...
mTreeBuilder->flushCharacters(); // empty the pending buffer
mTreeBuilder->ClearOps(); // now get rid of the failed ops
mTreeBuilder->SetOpSink(mExecutor->GetStage());
mExecutor->StartReadingFromStage();
mSpeculating = false;
// Copy state over
mLastWasCR = aLastWasCR;
mTokenizer->loadState(aTokenizer);
mTreeBuilder->loadState(aTreeBuilder);
} else {
// We've got a successful speculation and at least a moment ago it was
// the current speculation
if (!mSpeculations.ElementAt(0)->FlushToSink(mExecutor)) {
mExecutor->MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
return;
}
MOZ_ASSERT(!mExecutor->IsScriptExecuting(),
"ParseUntilBlocked() was supposed to ensure we don't come "
"here when scripts are executing.");
MOZ_ASSERT(!aTokenizer || mExecutor->IsInFlushLoop(),
"How are we here if "
"RunFlushLoop() didn't call ParseUntilBlocked() or we're not "
"committing to an encoding?");
mSpeculations.RemoveElementAt(0);
if (mSpeculations.IsEmpty()) {
if (mMode == VIEW_SOURCE_HTML) {
// If we looked for meta charset in the HTML View Source case.
mTokenizer->SetViewSourceOpSink(mExecutor->GetStage());
} else {
// yes, it was still the only speculation. Now stop speculating
// However, before telling the executor to read from stage, flush
// any pending ops straight to the executor, because otherwise
// they remain unflushed until we get more data from the network.
mTreeBuilder->SetOpSink(mExecutor);
auto r = mTreeBuilder->Flush(true);
if (r.isErr()) {
mExecutor->MarkAsBroken(r.unwrapErr());
return;
}
mTreeBuilder->SetOpSink(mExecutor->GetStage());
}
mExecutor->StartReadingFromStage();
mSpeculating = false;
}
}
nsCOMPtr<nsIRunnable> event = new nsHtml5StreamParserContinuation(this);
if (NS_FAILED(mEventTarget->Dispatch(event, nsIThread::DISPATCH_NORMAL))) {
NS_WARNING("Failed to dispatch nsHtml5StreamParserContinuation");
}
// A stream event might run before this event runs, but that's harmless.
#ifdef DEBUG
mAtomTable.SetPermittedLookupEventTarget(mEventTarget);
#endif
}
}
void nsHtml5StreamParser::ContinueAfterFailedCharsetSwitch() {
MOZ_ASSERT(NS_IsMainThread(), "Wrong thread!");
nsCOMPtr<nsIRunnable> event = new nsHtml5StreamParserContinuation(this);
if (NS_FAILED(mEventTarget->Dispatch(event, nsIThread::DISPATCH_NORMAL))) {
NS_WARNING("Failed to dispatch nsHtml5StreamParserContinuation");
}
}
class nsHtml5TimerKungFu : public Runnable {
private:
nsHtml5StreamParserPtr mStreamParser;
public:
explicit nsHtml5TimerKungFu(nsHtml5StreamParser* aStreamParser)
: Runnable("nsHtml5TimerKungFu"), mStreamParser(aStreamParser) {}
NS_IMETHOD Run() override {
mozilla::MutexAutoLock flushTimerLock(mStreamParser->mFlushTimerMutex);
if (mStreamParser->mFlushTimer) {
mStreamParser->mFlushTimer->Cancel();
mStreamParser->mFlushTimer = nullptr;
}
return NS_OK;
}
};
void nsHtml5StreamParser::DropTimer() {
MOZ_ASSERT(NS_IsMainThread(), "Wrong thread!");
/*
* Simply nulling out the timer wouldn't work, because if the timer is
* armed, it needs to be canceled first. Simply canceling it first wouldn't
* work, because nsTimerImpl::Cancel is not safe for calling from outside
* the thread where nsTimerImpl::Fire would run. It's not safe to
* dispatch a runnable to cancel the timer from the destructor of this
* class, because the timer has a weak (void*) pointer back to this instance
* of the stream parser and having the timer fire before the runnable
* cancels it would make the timer access a deleted object.
*
* This DropTimer method addresses these issues. This method must be called
* on the main thread before the destructor of this class is reached.
* The nsHtml5TimerKungFu object has an nsHtml5StreamParserPtr that addrefs
* this
* stream parser object to keep it alive until the runnable is done.
* The runnable cancels the timer on the parser thread, drops the timer
* and lets nsHtml5StreamParserPtr send a runnable back to the main thread to
* release the stream parser.
*/
mozilla::MutexAutoLock flushTimerLock(mFlushTimerMutex);
if (mFlushTimer) {
nsCOMPtr<nsIRunnable> event = new nsHtml5TimerKungFu(this);
if (NS_FAILED(mEventTarget->Dispatch(event, nsIThread::DISPATCH_NORMAL))) {
NS_WARNING("Failed to dispatch TimerKungFu event");
}
}
}
// Using a static, because the method name Notify is taken by the chardet
// callback.
void nsHtml5StreamParser::TimerCallback(nsITimer* aTimer, void* aClosure) {
(static_cast<nsHtml5StreamParser*>(aClosure))->TimerFlush();
}
void nsHtml5StreamParser::TimerFlush() {
MOZ_ASSERT(IsParserThread(), "Wrong thread!");
mozilla::MutexAutoLock autoLock(mTokenizerMutex);
MOZ_ASSERT(!mSpeculating, "Flush timer fired while speculating.");
// The timer fired if we got here. No need to cancel it. Mark it as
// not armed, though.
mFlushTimerArmed = false;
mFlushTimerEverFired = true;
if (IsTerminatedOrInterrupted()) {
return;
}
if (mMode == VIEW_SOURCE_HTML || mMode == VIEW_SOURCE_XML) {
auto r = mTreeBuilder->Flush(); // delete useless ops
if (r.isErr()) {
MarkAsBroken(r.unwrapErr());
return;
}
r = mTokenizer->FlushViewSource();
if (r.isErr()) {
MarkAsBroken(r.unwrapErr());
return;
}
if (r.unwrap()) {
nsCOMPtr<nsIRunnable> runnable(mExecutorFlusher);
if (NS_FAILED(DispatchToMain(runnable.forget()))) {
NS_WARNING("failed to dispatch executor flush event");
}
}
} else {
// we aren't speculating and we don't know when new data is
// going to arrive. Send data to the main thread.
auto r = mTreeBuilder->Flush(true);
if (r.isErr()) {
MarkAsBroken(r.unwrapErr());
return;
}
if (r.unwrap()) {
nsCOMPtr<nsIRunnable> runnable(mExecutorFlusher);
if (NS_FAILED(DispatchToMain(runnable.forget()))) {
NS_WARNING("failed to dispatch executor flush event");
}
}
}
}
void nsHtml5StreamParser::MarkAsBroken(nsresult aRv) {
MOZ_ASSERT(IsParserThread(), "Wrong thread!");
mTokenizerMutex.AssertCurrentThreadOwns();
Terminate();
mTreeBuilder->MarkAsBroken(aRv);
auto r = mTreeBuilder->Flush(false);
if (r.isOk()) {
MOZ_ASSERT(r.unwrap(), "Should have had the markAsBroken op!");
} else {
MOZ_CRASH("OOM prevents propagation of OOM state");
}
nsCOMPtr<nsIRunnable> runnable(mExecutorFlusher);
if (NS_FAILED(DispatchToMain(runnable.forget()))) {
NS_WARNING("failed to dispatch executor flush event");
}
}
nsresult nsHtml5StreamParser::DispatchToMain(
already_AddRefed<nsIRunnable>&& aRunnable) {
return SchedulerGroup::Dispatch(std::move(aRunnable));
}