gecko-dev/parser/html/nsHtml5TreeOpExecutor.cpp

1177 строки
36 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set sw=2 ts=2 et tw=79: */
/* 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 "mozilla/DebugOnly.h"
#include "mozilla/Likely.h"
#include "mozilla/dom/ScriptLoader.h"
#include "mozilla/dom/nsCSPService.h"
#include "GeckoProfiler.h"
#include "mozAutoDocUpdate.h"
#include "mozilla/IdleTaskRunner.h"
#include "mozilla/Preferences.h"
#include "mozilla/StaticPrefs.h"
#include "mozilla/css/Loader.h"
#include "nsContentUtils.h"
#include "nsDocShell.h"
#include "nsError.h"
#include "nsHtml5AutoPauseUpdate.h"
#include "nsHtml5Parser.h"
#include "nsHtml5StreamParser.h"
#include "nsHtml5Tokenizer.h"
#include "nsHtml5TreeBuilder.h"
#include "nsHtml5TreeOpExecutor.h"
#include "nsIContentSecurityPolicy.h"
#include "nsIContentViewer.h"
#include "nsIDocShell.h"
#include "nsIDocShellTreeItem.h"
#include "nsIHTMLDocument.h"
#include "nsINestedURI.h"
#include "nsIScriptContext.h"
#include "nsIScriptError.h"
#include "nsIScriptGlobalObject.h"
#include "nsIViewSourceChannel.h"
#include "nsNetUtil.h"
#include "xpcpublic.h"
using namespace mozilla;
NS_IMPL_ISUPPORTS_CYCLE_COLLECTION_INHERITED(nsHtml5TreeOpExecutor,
nsHtml5DocumentBuilder,
nsIContentSink)
class nsHtml5ExecutorReflusher : public Runnable
{
private:
RefPtr<nsHtml5TreeOpExecutor> mExecutor;
public:
explicit nsHtml5ExecutorReflusher(nsHtml5TreeOpExecutor* aExecutor)
: mozilla::Runnable("nsHtml5ExecutorReflusher")
, mExecutor(aExecutor)
{
}
NS_IMETHOD Run() override
{
mExecutor->RunFlushLoop();
return NS_OK;
}
};
class MOZ_RAII nsHtml5AutoFlush final
{
private:
RefPtr<nsHtml5TreeOpExecutor> mExecutor;
size_t mOpsToRemove;
public:
explicit nsHtml5AutoFlush(nsHtml5TreeOpExecutor* aExecutor)
: mExecutor(aExecutor)
, mOpsToRemove(aExecutor->OpQueueLength())
{
mExecutor->BeginFlush();
mExecutor->BeginDocUpdate();
}
~nsHtml5AutoFlush()
{
if (mExecutor->IsInDocUpdate()) {
mExecutor->EndDocUpdate();
} else {
// We aren't in an update if nsHtml5AutoPauseUpdate
// caused something to terminate the parser.
MOZ_RELEASE_ASSERT(
mExecutor->IsComplete(),
"How do we have mParser but the doc update isn't open?");
}
mExecutor->EndFlush();
mExecutor->RemoveFromStartOfOpQueue(mOpsToRemove);
}
void SetNumberOfOpsToRemove(size_t aOpsToRemove)
{
MOZ_ASSERT(aOpsToRemove < mOpsToRemove,
"Requested partial clearing of op queue but the number to clear "
"wasn't less than the length of the queue.");
mOpsToRemove = aOpsToRemove;
}
};
static mozilla::LinkedList<nsHtml5TreeOpExecutor>* gBackgroundFlushList =
nullptr;
StaticRefPtr<IdleTaskRunner> gBackgroundFlushRunner;
nsHtml5TreeOpExecutor::nsHtml5TreeOpExecutor()
: nsHtml5DocumentBuilder(false)
, mSuppressEOF(false)
, mReadingFromStage(false)
, mStreamParser(nullptr)
, mPreloadedURLs(23) // Mean # of preloadable resources per page on dmoz
, mSpeculationReferrerPolicy(mozilla::net::RP_Unset)
, mStarted(false)
, mRunFlushLoopOnStack(false)
, mCallContinueInterruptedParsingIfEnabled(false)
, mAlreadyComplainedAboutCharset(false)
{
}
nsHtml5TreeOpExecutor::~nsHtml5TreeOpExecutor()
{
if (gBackgroundFlushList && isInList()) {
ClearOpQueue();
removeFrom(*gBackgroundFlushList);
if (gBackgroundFlushList->isEmpty()) {
delete gBackgroundFlushList;
gBackgroundFlushList = nullptr;
if (gBackgroundFlushRunner) {
gBackgroundFlushRunner->Cancel();
gBackgroundFlushRunner = nullptr;
}
}
}
NS_ASSERTION(mOpQueue.IsEmpty(), "Somehow there's stuff in the op queue.");
}
// nsIContentSink
NS_IMETHODIMP
nsHtml5TreeOpExecutor::WillParse()
{
MOZ_ASSERT_UNREACHABLE("No one should call this");
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP
nsHtml5TreeOpExecutor::WillBuildModel(nsDTDMode aDTDMode)
{
mDocument->AddObserver(this);
WillBuildModelImpl();
GetDocument()->BeginLoad();
if (mDocShell && !GetDocument()->GetWindow() && !IsExternalViewSource()) {
// Not loading as data but script global object not ready
return MarkAsBroken(NS_ERROR_DOM_INVALID_STATE_ERR);
}
return NS_OK;
}
// This is called when the tree construction has ended
NS_IMETHODIMP
nsHtml5TreeOpExecutor::DidBuildModel(bool aTerminated)
{
if (mRunsToCompletion) {
return NS_OK;
}
MOZ_RELEASE_ASSERT(!IsInDocUpdate(),
"DidBuildModel from inside a doc update.");
// This comes from nsXMLContentSink and nsHTMLContentSink
// If this parser has been marked as broken, treat the end of parse as
// forced termination.
DidBuildModelImpl(aTerminated || NS_FAILED(IsBroken()));
if (!mLayoutStarted) {
// We never saw the body, and layout never got started. Force
// layout *now*, to get an initial reflow.
// NOTE: only force the layout if we are NOT destroying the
// docshell. If we are destroying it, then starting layout will
// likely cause us to crash, or at best waste a lot of time as we
// are just going to tear it down anyway.
bool destroying = true;
if (mDocShell) {
mDocShell->IsBeingDestroyed(&destroying);
}
if (!destroying) {
nsContentSink::StartLayout(false);
}
}
ScrollToRef();
mDocument->RemoveObserver(this);
if (!mParser) {
// DidBuildModelImpl may cause mParser to be nulled out
// Return early to avoid unblocking the onload event too many times.
return NS_OK;
}
// We may not have called BeginLoad() if loading is terminated before
// OnStartRequest call.
if (mStarted) {
mDocument->EndLoad();
}
GetParser()->DropStreamParser();
DropParserAndPerfHint();
#ifdef GATHER_DOCWRITE_STATISTICS
printf("UNSAFE SCRIPTS: %d\n", sUnsafeDocWrites);
printf("TOKENIZER-SAFE SCRIPTS: %d\n", sTokenSafeDocWrites);
printf("TREEBUILDER-SAFE SCRIPTS: %d\n", sTreeSafeDocWrites);
#endif
#ifdef DEBUG_NS_HTML5_TREE_OP_EXECUTOR_FLUSH
printf("MAX NOTIFICATION BATCH LEN: %d\n", sAppendBatchMaxSize);
if (sAppendBatchExaminations != 0) {
printf("AVERAGE SLOTS EXAMINED: %d\n",
sAppendBatchSlotsExamined / sAppendBatchExaminations);
}
#endif
return NS_OK;
}
NS_IMETHODIMP
nsHtml5TreeOpExecutor::WillInterrupt()
{
MOZ_ASSERT_UNREACHABLE("Don't call. For interface compat only.");
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP
nsHtml5TreeOpExecutor::WillResume()
{
MOZ_ASSERT_UNREACHABLE("Don't call. For interface compat only.");
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP
nsHtml5TreeOpExecutor::SetParser(nsParserBase* aParser)
{
mParser = aParser;
return NS_OK;
}
void
nsHtml5TreeOpExecutor::FlushPendingNotifications(FlushType aType)
{
if (aType >= FlushType::EnsurePresShellInitAndFrames) {
// Bug 577508 / 253951
nsContentSink::StartLayout(true);
}
}
nsISupports*
nsHtml5TreeOpExecutor::GetTarget()
{
return mDocument;
}
nsresult
nsHtml5TreeOpExecutor::MarkAsBroken(nsresult aReason)
{
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
mBroken = aReason;
if (mStreamParser) {
mStreamParser->Terminate();
}
// We are under memory pressure, but let's hope the following allocation
// works out so that we get to terminate and clean up the parser from
// a safer point.
if (mParser && mDocument) { // can mParser ever be null here?
nsCOMPtr<nsIRunnable> terminator = NewRunnableMethod(
"nsHtml5Parser::Terminate", GetParser(), &nsHtml5Parser::Terminate);
if (NS_FAILED(
mDocument->Dispatch(TaskCategory::Network, terminator.forget()))) {
NS_WARNING("failed to dispatch executor flush event");
}
}
return aReason;
}
static bool BackgroundFlushCallback(TimeStamp /*aDeadline*/)
{
RefPtr<nsHtml5TreeOpExecutor> ex = gBackgroundFlushList->popFirst();
if (ex) {
ex->RunFlushLoop();
}
if (gBackgroundFlushList && gBackgroundFlushList->isEmpty()) {
delete gBackgroundFlushList;
gBackgroundFlushList = nullptr;
gBackgroundFlushRunner->Cancel();
gBackgroundFlushRunner = nullptr;
return true;
}
return true;
}
void
nsHtml5TreeOpExecutor::ContinueInterruptedParsingAsync()
{
if (!mDocument || !mDocument->IsInBackgroundWindow()) {
nsCOMPtr<nsIRunnable> flusher = new nsHtml5ExecutorReflusher(this);
if (NS_FAILED(
mDocument->Dispatch(TaskCategory::Network, flusher.forget()))) {
NS_WARNING("failed to dispatch executor flush event");
}
} else {
if (!gBackgroundFlushList) {
gBackgroundFlushList = new mozilla::LinkedList<nsHtml5TreeOpExecutor>();
}
if (!isInList()) {
gBackgroundFlushList->insertBack(this);
}
if (gBackgroundFlushRunner) {
return;
}
// Now we set up a repetitive idle scheduler for flushing background list.
gBackgroundFlushRunner = IdleTaskRunner::Create(
&BackgroundFlushCallback,
"nsHtml5TreeOpExecutor::BackgroundFlushCallback",
250, // The hard deadline: 250ms.
nsContentSink::sInteractiveParseTime / 1000, // Required budget.
true, // repeating
[] { return false; }); // MayStopProcessing
}
}
void
nsHtml5TreeOpExecutor::FlushSpeculativeLoads()
{
nsTArray<nsHtml5SpeculativeLoad> speculativeLoadQueue;
mStage.MoveSpeculativeLoadsTo(speculativeLoadQueue);
nsHtml5SpeculativeLoad* start = speculativeLoadQueue.Elements();
nsHtml5SpeculativeLoad* end = start + speculativeLoadQueue.Length();
for (nsHtml5SpeculativeLoad* iter = start; iter < end; ++iter) {
if (MOZ_UNLIKELY(!mParser)) {
// An extension terminated the parser from a HTTP observer.
return;
}
iter->Perform(this);
}
}
class nsHtml5FlushLoopGuard
{
private:
RefPtr<nsHtml5TreeOpExecutor> mExecutor;
#ifdef DEBUG_NS_HTML5_TREE_OP_EXECUTOR_FLUSH
uint32_t mStartTime;
#endif
public:
explicit nsHtml5FlushLoopGuard(nsHtml5TreeOpExecutor* aExecutor)
: mExecutor(aExecutor)
#ifdef DEBUG_NS_HTML5_TREE_OP_EXECUTOR_FLUSH
, mStartTime(PR_IntervalToMilliseconds(PR_IntervalNow()))
#endif
{
mExecutor->mRunFlushLoopOnStack = true;
}
~nsHtml5FlushLoopGuard()
{
#ifdef DEBUG_NS_HTML5_TREE_OP_EXECUTOR_FLUSH
uint32_t timeOffTheEventLoop =
PR_IntervalToMilliseconds(PR_IntervalNow()) - mStartTime;
if (timeOffTheEventLoop >
nsHtml5TreeOpExecutor::sLongestTimeOffTheEventLoop) {
nsHtml5TreeOpExecutor::sLongestTimeOffTheEventLoop = timeOffTheEventLoop;
}
printf("Longest time off the event loop: %d\n",
nsHtml5TreeOpExecutor::sLongestTimeOffTheEventLoop);
#endif
mExecutor->mRunFlushLoopOnStack = false;
}
};
/**
* The purpose of the loop here is to avoid returning to the main event loop
*/
void
nsHtml5TreeOpExecutor::RunFlushLoop()
{
AUTO_PROFILER_LABEL("nsHtml5TreeOpExecutor::RunFlushLoop", OTHER);
if (mRunFlushLoopOnStack) {
// There's already a RunFlushLoop() on the call stack.
return;
}
nsHtml5FlushLoopGuard guard(this); // this is also the self-kungfu!
RefPtr<nsParserBase> parserKungFuDeathGrip(mParser);
// Remember the entry time
(void)nsContentSink::WillParseImpl();
for (;;) {
if (!mParser) {
// Parse has terminated.
ClearOpQueue(); // clear in order to be able to assert in destructor
return;
}
if (NS_FAILED(IsBroken())) {
return;
}
if (!parserKungFuDeathGrip->IsParserEnabled()) {
// The parser is blocked.
return;
}
if (mFlushState != eNotFlushing) {
// XXX Can this happen? In case it can, let's avoid crashing.
return;
}
// If there are scripts executing, then the content sink is jumping the gun
// (probably due to a synchronous XMLHttpRequest) and will re-enable us
// later, see bug 460706.
if (IsScriptExecuting()) {
return;
}
if (mReadingFromStage) {
nsTArray<nsHtml5SpeculativeLoad> speculativeLoadQueue;
MOZ_RELEASE_ASSERT(mFlushState == eNotFlushing,
"mOpQueue modified during flush.");
mStage.MoveOpsAndSpeculativeLoadsTo(mOpQueue, speculativeLoadQueue);
// Make sure speculative loads never start after the corresponding
// normal loads for the same URLs.
nsHtml5SpeculativeLoad* start = speculativeLoadQueue.Elements();
nsHtml5SpeculativeLoad* end = start + speculativeLoadQueue.Length();
for (nsHtml5SpeculativeLoad* iter = start; iter < end; ++iter) {
iter->Perform(this);
if (MOZ_UNLIKELY(!mParser)) {
// An extension terminated the parser from a HTTP observer.
ClearOpQueue(); // clear in order to be able to assert in destructor
return;
}
}
} else {
FlushSpeculativeLoads(); // Make sure speculative loads never start after
// the corresponding normal loads for the same
// URLs.
if (MOZ_UNLIKELY(!mParser)) {
// An extension terminated the parser from a HTTP observer.
ClearOpQueue(); // clear in order to be able to assert in destructor
return;
}
// Not sure if this grip is still needed, but previously, the code
// gripped before calling ParseUntilBlocked();
RefPtr<nsHtml5StreamParser> streamKungFuDeathGrip =
GetParser()->GetStreamParser();
mozilla::Unused << streamKungFuDeathGrip; // Not used within function
// Now parse content left in the document.write() buffer queue if any.
// This may generate tree ops on its own or dequeue a speculation.
nsresult rv = GetParser()->ParseUntilBlocked();
if (NS_FAILED(rv)) {
MarkAsBroken(rv);
return;
}
}
if (mOpQueue.IsEmpty()) {
// Avoid bothering the rest of the engine with a doc update if there's
// nothing to do.
return;
}
nsIContent* scriptElement = nullptr;
bool interrupted = false;
bool streamEnded = false;
{
// autoFlush clears mOpQueue in its destructor unless
// SetNumberOfOpsToRemove is called first, in which case only
// some ops from the start of the queue are cleared.
nsHtml5AutoFlush autoFlush(this);
nsHtml5TreeOperation* first = mOpQueue.Elements();
nsHtml5TreeOperation* last = first + mOpQueue.Length() - 1;
for (nsHtml5TreeOperation* iter = first;; ++iter) {
if (MOZ_UNLIKELY(!mParser)) {
// The previous tree op caused a call to nsIParser::Terminate().
return;
}
MOZ_ASSERT(IsInDocUpdate(),
"Tried to perform tree op outside update batch.");
nsresult rv =
iter->Perform(this, &scriptElement, &interrupted, &streamEnded);
if (NS_FAILED(rv)) {
MarkAsBroken(rv);
break;
}
// Be sure not to check the deadline if the last op was just performed.
if (MOZ_UNLIKELY(iter == last)) {
break;
} else if (MOZ_UNLIKELY(interrupted) ||
MOZ_UNLIKELY(nsContentSink::DidProcessATokenImpl() ==
NS_ERROR_HTMLPARSER_INTERRUPTED)) {
autoFlush.SetNumberOfOpsToRemove((iter - first) + 1);
nsHtml5TreeOpExecutor::ContinueInterruptedParsingAsync();
return;
}
}
if (MOZ_UNLIKELY(!mParser)) {
// The parse ended during an update pause.
return;
}
if (streamEnded) {
GetParser()->PermanentlyUndefineInsertionPoint();
}
} // end autoFlush
if (MOZ_UNLIKELY(!mParser)) {
// Ending the doc update caused a call to nsIParser::Terminate().
return;
}
if (streamEnded) {
DidBuildModel(false);
#ifdef DEBUG
if (scriptElement) {
nsCOMPtr<nsIScriptElement> sele = do_QueryInterface(scriptElement);
if (!sele) {
MOZ_ASSERT(nsNameSpaceManager::GetInstance()->mSVGDisabled,
"Node didn't QI to script, but SVG wasn't disabled.");
}
MOZ_ASSERT(sele->IsMalformed(), "Script wasn't marked as malformed.");
}
#endif
} else if (scriptElement) {
// must be tail call when mFlushState is eNotFlushing
RunScript(scriptElement);
// Always check the clock in nsContentSink right after a script
StopDeflecting();
if (nsContentSink::DidProcessATokenImpl() ==
NS_ERROR_HTMLPARSER_INTERRUPTED) {
#ifdef DEBUG_NS_HTML5_TREE_OP_EXECUTOR_FLUSH
printf("REFLUSH SCHEDULED (after script): %d\n",
++sTimesFlushLoopInterrupted);
#endif
nsHtml5TreeOpExecutor::ContinueInterruptedParsingAsync();
return;
}
}
}
}
nsresult
nsHtml5TreeOpExecutor::FlushDocumentWrite()
{
nsresult rv = IsBroken();
NS_ENSURE_SUCCESS(rv, rv);
FlushSpeculativeLoads(); // Make sure speculative loads never start after the
// corresponding normal loads for the same URLs.
if (MOZ_UNLIKELY(!mParser)) {
// The parse has ended.
ClearOpQueue(); // clear in order to be able to assert in destructor
return rv;
}
if (mFlushState != eNotFlushing) {
// XXX Can this happen? In case it can, let's avoid crashing.
return rv;
}
// avoid crashing near EOF
RefPtr<nsHtml5TreeOpExecutor> kungFuDeathGrip(this);
RefPtr<nsParserBase> parserKungFuDeathGrip(mParser);
mozilla::Unused
<< parserKungFuDeathGrip; // Intentionally not used within function
MOZ_RELEASE_ASSERT(!mReadingFromStage,
"Got doc write flush when reading from stage");
#ifdef DEBUG
mStage.AssertEmpty();
#endif
nsIContent* scriptElement = nullptr;
bool interrupted = false;
bool streamEnded = false;
{
// autoFlush clears mOpQueue in its destructor.
nsHtml5AutoFlush autoFlush(this);
nsHtml5TreeOperation* start = mOpQueue.Elements();
nsHtml5TreeOperation* end = start + mOpQueue.Length();
for (nsHtml5TreeOperation* iter = start; iter < end; ++iter) {
if (MOZ_UNLIKELY(!mParser)) {
// The previous tree op caused a call to nsIParser::Terminate().
return rv;
}
NS_ASSERTION(IsInDocUpdate(),
"Tried to perform tree op outside update batch.");
rv = iter->Perform(this, &scriptElement, &interrupted, &streamEnded);
if (NS_FAILED(rv)) {
MarkAsBroken(rv);
break;
}
}
if (MOZ_UNLIKELY(!mParser)) {
// The parse ended during an update pause.
return rv;
}
if (streamEnded) {
// This should be redundant but let's do it just in case.
GetParser()->PermanentlyUndefineInsertionPoint();
}
} // autoFlush
if (MOZ_UNLIKELY(!mParser)) {
// Ending the doc update caused a call to nsIParser::Terminate().
return rv;
}
if (streamEnded) {
DidBuildModel(false);
#ifdef DEBUG
if (scriptElement) {
nsCOMPtr<nsIScriptElement> sele = do_QueryInterface(scriptElement);
if (!sele) {
MOZ_ASSERT(nsNameSpaceManager::GetInstance()->mSVGDisabled,
"Node didn't QI to script, but SVG wasn't disabled.");
}
MOZ_ASSERT(sele->IsMalformed(), "Script wasn't marked as malformed.");
}
#endif
} else if (scriptElement) {
// must be tail call when mFlushState is eNotFlushing
RunScript(scriptElement);
}
return rv;
}
// copied from HTML content sink
bool
nsHtml5TreeOpExecutor::IsScriptEnabled()
{
// Note that if we have no document or no docshell or no global or whatnot we
// want to claim script _is_ enabled, so we don't parse the contents of
// <noscript> tags!
if (!mDocument || !mDocShell) {
return true;
}
return mDocument->IsScriptEnabled();
}
void
nsHtml5TreeOpExecutor::StartLayout(bool* aInterrupted)
{
if (mLayoutStarted || !mDocument) {
return;
}
nsHtml5AutoPauseUpdate autoPause(this);
if (MOZ_UNLIKELY(!mParser)) {
// got terminate
return;
}
nsContentSink::StartLayout(false);
if (mParser) {
*aInterrupted = !GetParser()->IsParserEnabled();
}
}
void
nsHtml5TreeOpExecutor::PauseDocUpdate(bool* aInterrupted)
{
// Pausing the document update allows JS to run, and potentially block
// further parsing.
nsHtml5AutoPauseUpdate autoPause(this);
if (MOZ_LIKELY(mParser)) {
*aInterrupted = !GetParser()->IsParserEnabled();
}
}
/**
* The reason why this code is here and not in the tree builder even in the
* main-thread case is to allow the control to return from the tokenizer
* before scripts run. This way, the tokenizer is not invoked re-entrantly
* although the parser is.
*
* The reason why this is called as a tail call when mFlushState is set to
* eNotFlushing is to allow re-entry to Flush() but only after the current
* Flush() has cleared the op queue and is otherwise done cleaning up after
* itself.
*/
void
nsHtml5TreeOpExecutor::RunScript(nsIContent* aScriptElement)
{
if (mRunsToCompletion) {
// We are in createContextualFragment() or in the upcoming document.parse().
// Do nothing. Let's not even mark scripts malformed here, because that
// could cause serialization weirdness later.
return;
}
MOZ_ASSERT(mParser, "Trying to run script with a terminated parser.");
MOZ_ASSERT(aScriptElement, "No script to run");
nsCOMPtr<nsIScriptElement> sele = do_QueryInterface(aScriptElement);
if (!sele) {
MOZ_ASSERT(nsNameSpaceManager::GetInstance()->mSVGDisabled,
"Node didn't QI to script, but SVG wasn't disabled.");
return;
}
if (sele->GetScriptDeferred() || sele->GetScriptAsync()) {
DebugOnly<bool> block = sele->AttemptToExecute();
NS_ASSERTION(!block, "Defer or async script tried to block.");
return;
}
MOZ_RELEASE_ASSERT(mFlushState == eNotFlushing,
"Tried to run script while flushing.");
mReadingFromStage = false;
sele->SetCreatorParser(GetParser());
// Copied from nsXMLContentSink
// Now tell the script that it's ready to go. This may execute the script
// or return true, or neither if the script doesn't need executing.
bool block = sele->AttemptToExecute();
// If the act of insertion evaluated the script, we're fine.
// Else, block the parser till the script has loaded.
if (block) {
if (mParser) {
GetParser()->BlockParser();
}
} else {
// mParser may have been nulled out by now, but the flusher deals
// If this event isn't needed, it doesn't do anything. It is sometimes
// necessary for the parse to continue after complex situations.
nsHtml5TreeOpExecutor::ContinueInterruptedParsingAsync();
}
}
void
nsHtml5TreeOpExecutor::Start()
{
MOZ_ASSERT(!mStarted, "Tried to start when already started.");
mStarted = true;
}
void
nsHtml5TreeOpExecutor::NeedsCharsetSwitchTo(NotNull<const Encoding*> aEncoding,
int32_t aSource,
uint32_t aLineNumber)
{
nsHtml5AutoPauseUpdate autoPause(this);
if (MOZ_UNLIKELY(!mParser)) {
// got terminate
return;
}
if (!mDocShell) {
return;
}
nsDocShell* docShell = static_cast<nsDocShell*>(mDocShell.get());
if (NS_SUCCEEDED(docShell->CharsetChangeStopDocumentLoad())) {
nsAutoCString charset;
aEncoding->Name(charset);
docShell->CharsetChangeReloadDocument(charset.get(), aSource);
}
// if the charset switch was accepted, mDocShell has called Terminate() on the
// parser by now
if (!mParser) {
// success
if (aSource == kCharsetFromMetaTag) {
MaybeComplainAboutCharset("EncLateMetaReload", false, aLineNumber);
}
return;
}
if (aSource == kCharsetFromMetaTag) {
MaybeComplainAboutCharset("EncLateMetaTooLate", true, aLineNumber);
}
GetParser()->ContinueAfterFailedCharsetSwitch();
}
void
nsHtml5TreeOpExecutor::MaybeComplainAboutCharset(const char* aMsgId,
bool aError,
uint32_t aLineNumber)
{
if (mAlreadyComplainedAboutCharset) {
return;
}
// The EncNoDeclaration case for advertising iframes is so common that it
// would result is way too many errors. The iframe case doesn't matter
// when the ad is an image or a Flash animation anyway. When the ad is
// textual, a misrendered ad probably isn't a huge loss for users.
// Let's suppress the message in this case.
// This means that errors about other different-origin iframes in mashups
// are lost as well, but generally, the site author isn't in control of
// the embedded different-origin pages anyway and can't fix problems even
// if alerted about them.
if (!strcmp(aMsgId, "EncNoDeclaration") && mDocShell) {
nsCOMPtr<nsIDocShellTreeItem> parent;
mDocShell->GetSameTypeParent(getter_AddRefs(parent));
if (parent) {
return;
}
}
mAlreadyComplainedAboutCharset = true;
nsContentUtils::ReportToConsole(aError ? nsIScriptError::errorFlag
: nsIScriptError::warningFlag,
NS_LITERAL_CSTRING("HTML parser"),
mDocument,
nsContentUtils::eHTMLPARSER_PROPERTIES,
aMsgId,
nullptr,
0,
nullptr,
EmptyString(),
aLineNumber);
}
void
nsHtml5TreeOpExecutor::ComplainAboutBogusProtocolCharset(nsIDocument* aDoc)
{
NS_ASSERTION(!mAlreadyComplainedAboutCharset,
"How come we already managed to complain?");
mAlreadyComplainedAboutCharset = true;
nsContentUtils::ReportToConsole(nsIScriptError::errorFlag,
NS_LITERAL_CSTRING("HTML parser"),
aDoc,
nsContentUtils::eHTMLPARSER_PROPERTIES,
"EncProtocolUnsupported");
}
nsHtml5Parser*
nsHtml5TreeOpExecutor::GetParser()
{
MOZ_ASSERT(!mRunsToCompletion);
return static_cast<nsHtml5Parser*>(mParser.get());
}
void
nsHtml5TreeOpExecutor::MoveOpsFrom(nsTArray<nsHtml5TreeOperation>& aOpQueue)
{
MOZ_RELEASE_ASSERT(mFlushState == eNotFlushing,
"Ops added to mOpQueue during tree op execution.");
mOpQueue.AppendElements(std::move(aOpQueue));
}
void
nsHtml5TreeOpExecutor::ClearOpQueue()
{
MOZ_RELEASE_ASSERT(mFlushState == eNotFlushing,
"mOpQueue cleared during tree op execution.");
mOpQueue.Clear();
}
void
nsHtml5TreeOpExecutor::RemoveFromStartOfOpQueue(size_t aNumberOfOpsToRemove)
{
MOZ_RELEASE_ASSERT(mFlushState == eNotFlushing,
"Ops removed from mOpQueue during tree op execution.");
mOpQueue.RemoveElementsAt(0, aNumberOfOpsToRemove);
}
void
nsHtml5TreeOpExecutor::InitializeDocWriteParserState(
nsAHtml5TreeBuilderState* aState,
int32_t aLine)
{
GetParser()->InitializeDocWriteParserState(aState, aLine);
}
nsIURI*
nsHtml5TreeOpExecutor::GetViewSourceBaseURI()
{
if (!mViewSourceBaseURI) {
// We query the channel for the baseURI because in certain situations it
// cannot otherwise be determined. If this process fails, fall back to the
// standard method.
nsCOMPtr<nsIViewSourceChannel> vsc =
do_QueryInterface(mDocument->GetChannel());
if (vsc) {
nsresult rv = vsc->GetBaseURI(getter_AddRefs(mViewSourceBaseURI));
if (NS_SUCCEEDED(rv) && mViewSourceBaseURI) {
return mViewSourceBaseURI;
}
}
nsCOMPtr<nsIURI> orig = mDocument->GetOriginalURI();
bool isViewSource;
orig->SchemeIs("view-source", &isViewSource);
if (isViewSource) {
nsCOMPtr<nsINestedURI> nested = do_QueryInterface(orig);
NS_ASSERTION(nested, "URI with scheme view-source didn't QI to nested!");
nested->GetInnerURI(getter_AddRefs(mViewSourceBaseURI));
} else {
// Fail gracefully if the base URL isn't a view-source: URL.
// Not sure if this can ever happen.
mViewSourceBaseURI = orig;
}
}
return mViewSourceBaseURI;
}
bool
nsHtml5TreeOpExecutor::IsExternalViewSource()
{
if (!StaticPrefs::view_source_editor_external()) {
return false;
}
bool isViewSource = false;
if (mDocumentURI) {
mDocumentURI->SchemeIs("view-source", &isViewSource);
}
return isViewSource;
}
// Speculative loading
nsIURI*
nsHtml5TreeOpExecutor::BaseURIForPreload()
{
// The URL of the document without <base>
nsIURI* documentURI = mDocument->GetDocumentURI();
// The URL of the document with non-speculative <base>
nsIURI* documentBaseURI = mDocument->GetDocBaseURI();
// If the two above are different, use documentBaseURI. If they are the same,
// the document object isn't aware of a <base>, so attempt to use the
// mSpeculationBaseURI or, failing, that, documentURI.
return (documentURI == documentBaseURI)
? (mSpeculationBaseURI ? mSpeculationBaseURI.get() : documentURI)
: documentBaseURI;
}
already_AddRefed<nsIURI>
nsHtml5TreeOpExecutor::ConvertIfNotPreloadedYet(const nsAString& aURL)
{
if (aURL.IsEmpty()) {
return nullptr;
}
nsIURI* base = BaseURIForPreload();
auto encoding = mDocument->GetDocumentCharacterSet();
nsCOMPtr<nsIURI> uri;
nsresult rv = NS_NewURI(getter_AddRefs(uri), aURL, encoding, base);
if (NS_FAILED(rv)) {
NS_WARNING("Failed to create a URI");
return nullptr;
}
if (ShouldPreloadURI(uri)) {
return uri.forget();
}
return nullptr;
}
bool
nsHtml5TreeOpExecutor::ShouldPreloadURI(nsIURI* aURI)
{
nsAutoCString spec;
nsresult rv = aURI->GetSpec(spec);
NS_ENSURE_SUCCESS(rv, false);
return mPreloadedURLs.EnsureInserted(spec);
}
void
nsHtml5TreeOpExecutor::PreloadScript(const nsAString& aURL,
const nsAString& aCharset,
const nsAString& aType,
const nsAString& aCrossOrigin,
const nsAString& aIntegrity,
bool aScriptFromHead,
bool aAsync,
bool aDefer,
bool aNoModule)
{
nsCOMPtr<nsIURI> uri = ConvertIfNotPreloadedYet(aURL);
if (!uri) {
return;
}
mDocument->ScriptLoader()->PreloadURI(uri,
aCharset,
aType,
aCrossOrigin,
aIntegrity,
aScriptFromHead,
aAsync,
aDefer,
aNoModule,
mSpeculationReferrerPolicy);
}
void
nsHtml5TreeOpExecutor::PreloadStyle(const nsAString& aURL,
const nsAString& aCharset,
const nsAString& aCrossOrigin,
const nsAString& aReferrerPolicy,
const nsAString& aIntegrity)
{
nsCOMPtr<nsIURI> uri = ConvertIfNotPreloadedYet(aURL);
if (!uri) {
return;
}
mozilla::net::ReferrerPolicy referrerPolicy = mSpeculationReferrerPolicy;
mozilla::net::ReferrerPolicy styleReferrerPolicy =
mozilla::net::AttributeReferrerPolicyFromString(aReferrerPolicy);
if (styleReferrerPolicy != mozilla::net::RP_Unset) {
referrerPolicy = styleReferrerPolicy;
}
mDocument->PreloadStyle(uri,
Encoding::ForLabel(aCharset),
aCrossOrigin,
referrerPolicy,
aIntegrity);
}
void
nsHtml5TreeOpExecutor::PreloadImage(const nsAString& aURL,
const nsAString& aCrossOrigin,
const nsAString& aSrcset,
const nsAString& aSizes,
const nsAString& aImageReferrerPolicy)
{
nsCOMPtr<nsIURI> baseURI = BaseURIForPreload();
bool isImgSet = false;
nsCOMPtr<nsIURI> uri =
mDocument->ResolvePreloadImage(baseURI, aURL, aSrcset, aSizes, &isImgSet);
if (uri && ShouldPreloadURI(uri)) {
// use document wide referrer policy
mozilla::net::ReferrerPolicy referrerPolicy = mSpeculationReferrerPolicy;
mozilla::net::ReferrerPolicy imageReferrerPolicy =
mozilla::net::AttributeReferrerPolicyFromString(aImageReferrerPolicy);
if (imageReferrerPolicy != mozilla::net::RP_Unset) {
referrerPolicy = imageReferrerPolicy;
}
mDocument->MaybePreLoadImage(uri, aCrossOrigin, referrerPolicy, isImgSet);
}
}
// These calls inform the document of picture state and seen sources, such that
// it can use them to inform ResolvePreLoadImage as necessary
void
nsHtml5TreeOpExecutor::PreloadPictureSource(const nsAString& aSrcset,
const nsAString& aSizes,
const nsAString& aType,
const nsAString& aMedia)
{
mDocument->PreloadPictureImageSource(aSrcset, aSizes, aType, aMedia);
}
void
nsHtml5TreeOpExecutor::PreloadOpenPicture()
{
mDocument->PreloadPictureOpened();
}
void
nsHtml5TreeOpExecutor::PreloadEndPicture()
{
mDocument->PreloadPictureClosed();
}
void
nsHtml5TreeOpExecutor::AddBase(const nsAString& aURL)
{
auto encoding = mDocument->GetDocumentCharacterSet();
nsresult rv = NS_NewURI(
getter_AddRefs(mViewSourceBaseURI), aURL, encoding, GetViewSourceBaseURI());
if (NS_FAILED(rv)) {
mViewSourceBaseURI = nullptr;
}
}
void
nsHtml5TreeOpExecutor::SetSpeculationBase(const nsAString& aURL)
{
if (mSpeculationBaseURI) {
// the first one wins
return;
}
auto encoding = mDocument->GetDocumentCharacterSet();
DebugOnly<nsresult> rv = NS_NewURI(getter_AddRefs(mSpeculationBaseURI),
aURL,
encoding,
mDocument->GetDocumentURI());
NS_WARNING_ASSERTION(NS_SUCCEEDED(rv), "Failed to create a URI");
}
void
nsHtml5TreeOpExecutor::SetSpeculationReferrerPolicy(
const nsAString& aReferrerPolicy)
{
// Specs says:
// - Let value be the result of stripping leading and trailing whitespace from
// the value of element's content attribute.
// - If value is not the empty string, then:
if (aReferrerPolicy.IsEmpty()) {
return;
}
ReferrerPolicy policy =
mozilla::net::ReferrerPolicyFromString(aReferrerPolicy);
// Specs says:
// - If policy is not the empty string, then set element's node document's
// referrer policy to policy
if (policy != mozilla::net::RP_Unset) {
SetSpeculationReferrerPolicy(policy);
}
}
void
nsHtml5TreeOpExecutor::AddSpeculationCSP(const nsAString& aCSP)
{
if (!StaticPrefs::security_csp_enable()) {
return;
}
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
nsIPrincipal* principal = mDocument->NodePrincipal();
nsCOMPtr<nsIContentSecurityPolicy> preloadCsp;
nsresult rv = principal->EnsurePreloadCSP(mDocument, getter_AddRefs(preloadCsp));
NS_ENSURE_SUCCESS_VOID(rv);
// please note that meta CSPs and CSPs delivered through a header need
// to be joined together.
rv =
preloadCsp->AppendPolicy(aCSP,
false, // csp via meta tag can not be report only
true); // delivered through the meta tag
NS_ENSURE_SUCCESS_VOID(rv);
mDocument->ApplySettingsFromCSP(true);
}
void
nsHtml5TreeOpExecutor::SetSpeculationReferrerPolicy(
ReferrerPolicy aReferrerPolicy)
{
// Record "speculated" referrer policy locally and thread through the
// speculation phase. The actual referrer policy will be set by
// HTMLMetaElement::BindToTree().
mSpeculationReferrerPolicy = aReferrerPolicy;
}
#ifdef DEBUG_NS_HTML5_TREE_OP_EXECUTOR_FLUSH
uint32_t nsHtml5TreeOpExecutor::sAppendBatchMaxSize = 0;
uint32_t nsHtml5TreeOpExecutor::sAppendBatchSlotsExamined = 0;
uint32_t nsHtml5TreeOpExecutor::sAppendBatchExaminations = 0;
uint32_t nsHtml5TreeOpExecutor::sLongestTimeOffTheEventLoop = 0;
uint32_t nsHtml5TreeOpExecutor::sTimesFlushLoopInterrupted = 0;
#endif