gecko/parser/html/nsHtml5TreeOpExecutor.cpp
2011-10-17 10:59:28 -04:00

986 lines
29 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set sw=2 ts=2 et tw=79: */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Pierre Phaneuf <pp@ludusdesign.com>
* Henri Sivonen <hsivonen@iki.fi>
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "nsHtml5TreeOpExecutor.h"
#include "nsScriptLoader.h"
#include "nsIMarkupDocumentViewer.h"
#include "nsIContentViewer.h"
#include "nsIDocShellTreeItem.h"
#include "nsIStyleSheetLinkingElement.h"
#include "nsStyleLinkElement.h"
#include "nsIDocShell.h"
#include "nsIScriptGlobalObject.h"
#include "nsIScriptGlobalObjectOwner.h"
#include "nsIScriptSecurityManager.h"
#include "nsIWebShellServices.h"
#include "nsContentUtils.h"
#include "mozAutoDocUpdate.h"
#include "nsNetUtil.h"
#include "nsHtml5Parser.h"
#include "nsHtml5Tokenizer.h"
#include "nsHtml5TreeBuilder.h"
#include "nsHtml5StreamParser.h"
#include "mozilla/css/Loader.h"
#include "mozilla/Util.h" // DebugOnly
using namespace mozilla;
NS_IMPL_CYCLE_COLLECTION_CLASS(nsHtml5TreeOpExecutor)
NS_INTERFACE_TABLE_HEAD_CYCLE_COLLECTION_INHERITED(nsHtml5TreeOpExecutor)
NS_INTERFACE_TABLE_INHERITED1(nsHtml5TreeOpExecutor,
nsIContentSink)
NS_INTERFACE_TABLE_TAIL_INHERITING(nsContentSink)
NS_IMPL_ADDREF_INHERITED(nsHtml5TreeOpExecutor, nsContentSink)
NS_IMPL_RELEASE_INHERITED(nsHtml5TreeOpExecutor, nsContentSink)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(nsHtml5TreeOpExecutor, nsContentSink)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NSCOMARRAY(mOwnedElements)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(nsHtml5TreeOpExecutor, nsContentSink)
NS_IMPL_CYCLE_COLLECTION_UNLINK_NSCOMARRAY(mOwnedElements)
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
class nsHtml5ExecutorReflusher : public nsRunnable
{
private:
nsRefPtr<nsHtml5TreeOpExecutor> mExecutor;
public:
nsHtml5ExecutorReflusher(nsHtml5TreeOpExecutor* aExecutor)
: mExecutor(aExecutor)
{}
NS_IMETHODIMP Run()
{
mExecutor->RunFlushLoop();
return NS_OK;
}
};
nsHtml5TreeOpExecutor::nsHtml5TreeOpExecutor()
{
mPreloadedURLs.Init(23); // Mean # of preloadable resources per page on dmoz
// zeroing operator new for everything else
}
nsHtml5TreeOpExecutor::~nsHtml5TreeOpExecutor()
{
NS_ASSERTION(mOpQueue.IsEmpty(), "Somehow there's stuff in the op queue.");
}
// nsIContentSink
NS_IMETHODIMP
nsHtml5TreeOpExecutor::WillParse()
{
NS_NOTREACHED("No one should call this");
return NS_ERROR_NOT_IMPLEMENTED;
}
// This is called when the tree construction has ended
NS_IMETHODIMP
nsHtml5TreeOpExecutor::DidBuildModel(bool aTerminated)
{
NS_PRECONDITION(mStarted, "Bad life cycle.");
if (!aTerminated) {
// This is needed to avoid unblocking loads too many times on one hand
// and on the other hand to avoid destroying the frame constructor from
// within an update batch. See bug 537683.
EndDocUpdate();
// If the above caused a call to nsIParser::Terminate(), let that call
// win.
if (!mParser) {
return NS_OK;
}
}
GetParser()->DropStreamParser();
// This comes from nsXMLContentSink and nsHTMLContentSink
DidBuildModelImpl(aTerminated);
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->ScriptLoader()->RemoveObserver(this);
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;
}
mDocument->EndLoad();
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()
{
NS_NOTREACHED("Don't call. For interface compat only.");
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP
nsHtml5TreeOpExecutor::WillResume()
{
NS_NOTREACHED("Don't call. For interface compat only.");
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP
nsHtml5TreeOpExecutor::SetParser(nsIParser* aParser)
{
mParser = aParser;
return NS_OK;
}
void
nsHtml5TreeOpExecutor::FlushPendingNotifications(mozFlushType aType)
{
if (aType >= Flush_InterruptibleLayout) {
// Bug 577508 / 253951
nsContentSink::StartLayout(true);
}
}
void
nsHtml5TreeOpExecutor::SetDocumentCharsetAndSource(nsACString& aCharset, PRInt32 aCharsetSource)
{
if (mDocument) {
mDocument->SetDocumentCharacterSetSource(aCharsetSource);
mDocument->SetDocumentCharacterSet(aCharset);
}
if (mDocShell) {
// the following logic to get muCV is copied from
// nsHTMLDocument::StartDocumentLoad
// We need to call muCV->SetPrevDocCharacterSet here in case
// the charset is detected by parser DetectMetaTag
nsCOMPtr<nsIMarkupDocumentViewer> mucv;
nsCOMPtr<nsIContentViewer> cv;
mDocShell->GetContentViewer(getter_AddRefs(cv));
if (cv) {
mucv = do_QueryInterface(cv);
} else {
// in this block of code, if we get an error result, we return
// it but if we get a null pointer, that's perfectly legal for
// parent and parentContentViewer
nsCOMPtr<nsIDocShellTreeItem> docShellAsItem =
do_QueryInterface(mDocShell);
if (!docShellAsItem) {
return;
}
nsCOMPtr<nsIDocShellTreeItem> parentAsItem;
docShellAsItem->GetSameTypeParent(getter_AddRefs(parentAsItem));
nsCOMPtr<nsIDocShell> parent(do_QueryInterface(parentAsItem));
if (parent) {
nsCOMPtr<nsIContentViewer> parentContentViewer;
nsresult rv =
parent->GetContentViewer(getter_AddRefs(parentContentViewer));
if (NS_SUCCEEDED(rv) && parentContentViewer) {
mucv = do_QueryInterface(parentContentViewer);
}
}
}
if (mucv) {
mucv->SetPrevDocCharacterSet(aCharset);
}
}
}
nsISupports*
nsHtml5TreeOpExecutor::GetTarget()
{
return mDocument;
}
// nsContentSink overrides
void
nsHtml5TreeOpExecutor::UpdateChildCounts()
{
// No-op
}
void
nsHtml5TreeOpExecutor::MarkAsBroken()
{
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
NS_ASSERTION(!mFragmentMode, "Fragment parsers can't be broken!");
mBroken = true;
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) { // can mParser ever be null here?
nsCOMPtr<nsIRunnable> terminator =
NS_NewRunnableMethod(GetParser(), &nsHtml5Parser::Terminate);
if (NS_FAILED(NS_DispatchToMainThread(terminator))) {
NS_WARNING("failed to dispatch executor flush event");
}
}
}
nsresult
nsHtml5TreeOpExecutor::FlushTags()
{
return NS_OK;
}
void
nsHtml5TreeOpExecutor::PostEvaluateScript(nsIScriptElement *aElement)
{
nsCOMPtr<nsIHTMLDocument> htmlDocument = do_QueryInterface(mDocument);
NS_ASSERTION(htmlDocument, "Document didn't QI into HTML document.");
htmlDocument->ScriptExecuted(aElement);
}
void
nsHtml5TreeOpExecutor::ContinueInterruptedParsingAsync()
{
nsCOMPtr<nsIRunnable> flusher = new nsHtml5ExecutorReflusher(this);
if (NS_FAILED(NS_DispatchToMainThread(flusher))) {
NS_WARNING("failed to dispatch executor flush event");
}
}
void
nsHtml5TreeOpExecutor::UpdateStyleSheet(nsIContent* aElement)
{
// Break out of the doc update created by Flush() to zap a runnable
// waiting to call UpdateStyleSheet without the right observer
EndDocUpdate();
if (NS_UNLIKELY(!mParser)) {
// EndDocUpdate ran stuff that called nsIParser::Terminate()
return;
}
nsCOMPtr<nsIStyleSheetLinkingElement> ssle(do_QueryInterface(aElement));
NS_ASSERTION(ssle, "Node didn't QI to style.");
ssle->SetEnableUpdates(true);
bool willNotify;
bool isAlternate;
nsresult rv = ssle->UpdateStyleSheet(mFragmentMode ? nsnull : this,
&willNotify,
&isAlternate);
if (NS_SUCCEEDED(rv) && willNotify && !isAlternate && !mFragmentMode) {
++mPendingSheetCount;
mScriptLoader->AddExecuteBlocker();
}
if (aElement->IsHTML(nsGkAtoms::link)) {
// look for <link rel="next" href="url">
nsAutoString relVal;
aElement->GetAttr(kNameSpaceID_None, nsGkAtoms::rel, relVal);
if (!relVal.IsEmpty()) {
// XXX seems overkill to generate this string array
nsAutoTArray<nsString, 4> linkTypes;
nsStyleLinkElement::ParseLinkTypes(relVal, linkTypes);
bool hasPrefetch = linkTypes.Contains(NS_LITERAL_STRING("prefetch"));
if (hasPrefetch || linkTypes.Contains(NS_LITERAL_STRING("next"))) {
nsAutoString hrefVal;
aElement->GetAttr(kNameSpaceID_None, nsGkAtoms::href, hrefVal);
if (!hrefVal.IsEmpty()) {
PrefetchHref(hrefVal, aElement, hasPrefetch);
}
}
if (linkTypes.Contains(NS_LITERAL_STRING("dns-prefetch"))) {
nsAutoString hrefVal;
aElement->GetAttr(kNameSpaceID_None, nsGkAtoms::href, hrefVal);
if (!hrefVal.IsEmpty()) {
PrefetchDNS(hrefVal);
}
}
}
}
// Re-open update
BeginDocUpdate();
}
void
nsHtml5TreeOpExecutor::FlushSpeculativeLoads()
{
nsTArray<nsHtml5SpeculativeLoad> speculativeLoadQueue;
mStage.MoveSpeculativeLoadsTo(speculativeLoadQueue);
const nsHtml5SpeculativeLoad* start = speculativeLoadQueue.Elements();
const nsHtml5SpeculativeLoad* end = start + speculativeLoadQueue.Length();
for (nsHtml5SpeculativeLoad* iter = const_cast<nsHtml5SpeculativeLoad*>(start);
iter < end;
++iter) {
if (NS_UNLIKELY(!mParser)) {
// An extension terminated the parser from a HTTP observer.
return;
}
iter->Perform(this);
}
}
class nsHtml5FlushLoopGuard
{
private:
nsRefPtr<nsHtml5TreeOpExecutor> mExecutor;
#ifdef DEBUG_NS_HTML5_TREE_OP_EXECUTOR_FLUSH
PRUint32 mStartTime;
#endif
public:
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
PRUint32 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()
{
if (mRunFlushLoopOnStack) {
// There's already a RunFlushLoop() on the call stack.
return;
}
nsHtml5FlushLoopGuard guard(this); // this is also the self-kungfu!
nsCOMPtr<nsIParser> parserKungFuDeathGrip(mParser);
// Remember the entry time
(void) nsContentSink::WillParseImpl();
for (;;) {
if (!mParser) {
// Parse has terminated.
mOpQueue.Clear(); // clear in order to be able to assert in destructor
return;
}
if (IsBroken()) {
return;
}
if (!mParser->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;
mStage.MoveOpsAndSpeculativeLoadsTo(mOpQueue, speculativeLoadQueue);
// Make sure speculative loads never start after the corresponding
// normal loads for the same URLs.
const nsHtml5SpeculativeLoad* start = speculativeLoadQueue.Elements();
const nsHtml5SpeculativeLoad* end = start + speculativeLoadQueue.Length();
for (nsHtml5SpeculativeLoad* iter = (nsHtml5SpeculativeLoad*)start;
iter < end;
++iter) {
iter->Perform(this);
if (NS_UNLIKELY(!mParser)) {
// An extension terminated the parser from a HTTP observer.
mOpQueue.Clear(); // 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 (NS_UNLIKELY(!mParser)) {
// An extension terminated the parser from a HTTP observer.
mOpQueue.Clear(); // 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();
nsRefPtr<nsHtml5StreamParser> streamKungFuDeathGrip =
GetParser()->GetStreamParser();
// Now parse content left in the document.write() buffer queue if any.
// This may generate tree ops on its own or dequeue a speculation.
GetParser()->ParseUntilBlocked();
}
if (mOpQueue.IsEmpty()) {
// Avoid bothering the rest of the engine with a doc update if there's
// nothing to do.
return;
}
mFlushState = eInFlush;
nsIContent* scriptElement = nsnull;
BeginDocUpdate();
PRUint32 numberOfOpsToFlush = mOpQueue.Length();
mElementsSeenInThisAppendBatch.SetCapacity(numberOfOpsToFlush * 2);
const nsHtml5TreeOperation* first = mOpQueue.Elements();
const nsHtml5TreeOperation* last = first + numberOfOpsToFlush - 1;
for (nsHtml5TreeOperation* iter = const_cast<nsHtml5TreeOperation*>(first);;) {
if (NS_UNLIKELY(!mParser)) {
// The previous tree op caused a call to nsIParser::Terminate().
break;
}
NS_ASSERTION(mFlushState == eInDocUpdate,
"Tried to perform tree op outside update batch.");
iter->Perform(this, &scriptElement);
// Be sure not to check the deadline if the last op was just performed.
if (NS_UNLIKELY(iter == last)) {
break;
} else if (NS_UNLIKELY(nsContentSink::DidProcessATokenImpl() ==
NS_ERROR_HTMLPARSER_INTERRUPTED)) {
mOpQueue.RemoveElementsAt(0, (iter - first) + 1);
EndDocUpdate();
mFlushState = eNotFlushing;
#ifdef DEBUG_NS_HTML5_TREE_OP_EXECUTOR_FLUSH
printf("REFLUSH SCHEDULED (executing ops): %d\n",
++sTimesFlushLoopInterrupted);
#endif
nsHtml5TreeOpExecutor::ContinueInterruptedParsingAsync();
return;
}
++iter;
}
mOpQueue.Clear();
EndDocUpdate();
mFlushState = eNotFlushing;
if (NS_UNLIKELY(!mParser)) {
// The parse ended already.
return;
}
if (scriptElement) {
// must be tail call when mFlushState is eNotFlushing
RunScript(scriptElement);
// The script execution machinery makes sure this doesn't get deflected.
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;
}
}
}
}
void
nsHtml5TreeOpExecutor::FlushDocumentWrite()
{
FlushSpeculativeLoads(); // Make sure speculative loads never start after the
// corresponding normal loads for the same URLs.
if (NS_UNLIKELY(!mParser)) {
// The parse has ended.
mOpQueue.Clear(); // clear in order to be able to assert in destructor
return;
}
if (mFlushState != eNotFlushing) {
// XXX Can this happen? In case it can, let's avoid crashing.
return;
}
mFlushState = eInFlush;
// avoid crashing near EOF
nsRefPtr<nsHtml5TreeOpExecutor> kungFuDeathGrip(this);
nsCOMPtr<nsIParser> parserKungFuDeathGrip(mParser);
NS_ASSERTION(!mReadingFromStage,
"Got doc write flush when reading from stage");
#ifdef DEBUG
mStage.AssertEmpty();
#endif
nsIContent* scriptElement = nsnull;
BeginDocUpdate();
PRUint32 numberOfOpsToFlush = mOpQueue.Length();
mElementsSeenInThisAppendBatch.SetCapacity(numberOfOpsToFlush * 2);
const nsHtml5TreeOperation* start = mOpQueue.Elements();
const nsHtml5TreeOperation* end = start + numberOfOpsToFlush;
for (nsHtml5TreeOperation* iter = const_cast<nsHtml5TreeOperation*>(start);
iter < end;
++iter) {
if (NS_UNLIKELY(!mParser)) {
// The previous tree op caused a call to nsIParser::Terminate().
break;
}
NS_ASSERTION(mFlushState == eInDocUpdate,
"Tried to perform tree op outside update batch.");
iter->Perform(this, &scriptElement);
}
mOpQueue.Clear();
EndDocUpdate();
mFlushState = eNotFlushing;
if (NS_UNLIKELY(!mParser)) {
// Ending the doc update caused a call to nsIParser::Terminate().
return;
}
if (scriptElement) {
// must be tail call when mFlushState is eNotFlushing
RunScript(scriptElement);
}
}
// copied from HTML content sink
bool
nsHtml5TreeOpExecutor::IsScriptEnabled()
{
if (!mDocument || !mDocShell)
return true;
nsCOMPtr<nsIScriptGlobalObject> globalObject = mDocument->GetScriptGlobalObject();
// Getting context is tricky if the document hasn't had its
// GlobalObject set yet
if (!globalObject) {
nsCOMPtr<nsIScriptGlobalObjectOwner> owner = do_GetInterface(mDocShell);
NS_ENSURE_TRUE(owner, true);
globalObject = owner->GetScriptGlobalObject();
NS_ENSURE_TRUE(globalObject, true);
}
nsIScriptContext *scriptContext = globalObject->GetContext();
NS_ENSURE_TRUE(scriptContext, true);
JSContext* cx = scriptContext->GetNativeContext();
NS_ENSURE_TRUE(cx, true);
bool enabled = true;
nsContentUtils::GetSecurityManager()->
CanExecuteScripts(cx, mDocument->NodePrincipal(), &enabled);
return enabled;
}
void
nsHtml5TreeOpExecutor::SetDocumentMode(nsHtml5DocumentMode m)
{
nsCompatibility mode = eCompatibility_NavQuirks;
switch (m) {
case STANDARDS_MODE:
mode = eCompatibility_FullStandards;
break;
case ALMOST_STANDARDS_MODE:
mode = eCompatibility_AlmostStandards;
break;
case QUIRKS_MODE:
mode = eCompatibility_NavQuirks;
break;
}
nsCOMPtr<nsIHTMLDocument> htmlDocument = do_QueryInterface(mDocument);
NS_ASSERTION(htmlDocument, "Document didn't QI into HTML document.");
htmlDocument->SetCompatibilityMode(mode);
}
void
nsHtml5TreeOpExecutor::StartLayout() {
if (mLayoutStarted || !mDocument) {
return;
}
EndDocUpdate();
if (NS_UNLIKELY(!mParser)) {
// got terminate
return;
}
nsContentSink::StartLayout(false);
BeginDocUpdate();
}
/**
* 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)
{
NS_ASSERTION(aScriptElement, "No script to run");
nsCOMPtr<nsIScriptElement> sele = do_QueryInterface(aScriptElement);
if (!mParser) {
NS_ASSERTION(sele->IsMalformed(), "Script wasn't marked as malformed.");
// We got here not because of an end tag but because the tree builder
// popped an incomplete script element on EOF. Returning here to avoid
// calling back into mParser anymore.
return;
}
if (mFragmentMode) {
if (mPreventScriptExecution) {
sele->PreventExecution();
}
return;
}
if (sele->GetScriptDeferred() || sele->GetScriptAsync()) {
#ifdef DEBUG
nsresult rv =
#endif
aScriptElement->DoneAddingChildren(true); // scripts ignore the argument
NS_ASSERTION(rv != NS_ERROR_HTMLPARSER_BLOCK,
"Defer or async script tried to block.");
return;
}
NS_ASSERTION(mFlushState == eNotFlushing, "Tried to run script when flushing.");
mReadingFromStage = false;
sele->SetCreatorParser(mParser);
// Notify our document that we're loading this script.
nsCOMPtr<nsIHTMLDocument> htmlDocument = do_QueryInterface(mDocument);
NS_ASSERTION(htmlDocument, "Document didn't QI into HTML document.");
htmlDocument->ScriptLoading(sele);
// Copied from nsXMLContentSink
// Now tell the script that it's ready to go. This may execute the script
// or return NS_ERROR_HTMLPARSER_BLOCK. Or neither if the script doesn't
// need executing.
nsresult rv = aScriptElement->DoneAddingChildren(true);
// If the act of insertion evaluated the script, we're fine.
// Else, block the parser till the script has loaded.
if (rv == NS_ERROR_HTMLPARSER_BLOCK) {
mScriptElements.AppendObject(sele);
if (mParser) {
mParser->BlockParser();
}
} else {
// This may have already happened if the script executed, but in case
// it didn't then remove the element so that it doesn't get stuck forever.
htmlDocument->ScriptExecuted(sele);
// 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();
}
}
nsresult
nsHtml5TreeOpExecutor::Init(nsIDocument* aDoc,
nsIURI* aURI,
nsISupports* aContainer,
nsIChannel* aChannel)
{
return nsContentSink::Init(aDoc, aURI, aContainer, aChannel);
}
void
nsHtml5TreeOpExecutor::Start()
{
NS_PRECONDITION(!mStarted, "Tried to start when already started.");
mStarted = true;
}
void
nsHtml5TreeOpExecutor::NeedsCharsetSwitchTo(const char* aEncoding,
PRInt32 aSource)
{
EndDocUpdate();
if (NS_UNLIKELY(!mParser)) {
// got terminate
return;
}
nsCOMPtr<nsIWebShellServices> wss = do_QueryInterface(mDocShell);
if (!wss) {
return;
}
// ask the webshellservice to load the URL
if (NS_SUCCEEDED(wss->StopDocumentLoad())) {
wss->ReloadDocument(aEncoding, aSource);
}
// if the charset switch was accepted, wss has called Terminate() on the
// parser by now
if (!mParser) {
// success
return;
}
GetParser()->ContinueAfterFailedCharsetSwitch();
BeginDocUpdate();
}
nsHtml5Parser*
nsHtml5TreeOpExecutor::GetParser()
{
return static_cast<nsHtml5Parser*>(mParser.get());
}
nsHtml5Tokenizer*
nsHtml5TreeOpExecutor::GetTokenizer()
{
return GetParser()->GetTokenizer();
}
void
nsHtml5TreeOpExecutor::Reset()
{
DropHeldElements();
mReadingFromStage = false;
mOpQueue.Clear();
mStarted = false;
mFlushState = eNotFlushing;
mRunFlushLoopOnStack = false;
NS_ASSERTION(!mBroken, "Fragment parser got broken.");
}
void
nsHtml5TreeOpExecutor::DropHeldElements()
{
mScriptLoader = nsnull;
mDocument = nsnull;
mNodeInfoManager = nsnull;
mCSSLoader = nsnull;
mDocumentURI = nsnull;
mDocShell = nsnull;
mOwnedElements.Clear();
}
void
nsHtml5TreeOpExecutor::MoveOpsFrom(nsTArray<nsHtml5TreeOperation>& aOpQueue)
{
NS_PRECONDITION(mFlushState == eNotFlushing, "mOpQueue modified during tree op execution.");
if (mOpQueue.IsEmpty()) {
mOpQueue.SwapElements(aOpQueue);
return;
}
mOpQueue.MoveElementsFrom(aOpQueue);
}
void
nsHtml5TreeOpExecutor::InitializeDocWriteParserState(nsAHtml5TreeBuilderState* aState, PRInt32 aLine)
{
GetParser()->InitializeDocWriteParserState(aState, aLine);
}
// Speculative loading
already_AddRefed<nsIURI>
nsHtml5TreeOpExecutor::ConvertIfNotPreloadedYet(const nsAString& aURL)
{
if (aURL.IsEmpty()) {
return nsnull;
}
// 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.
nsIURI* base = (documentURI == documentBaseURI) ?
(mSpeculationBaseURI ?
mSpeculationBaseURI.get() : documentURI)
: documentBaseURI;
const nsCString& charset = mDocument->GetDocumentCharacterSet();
nsCOMPtr<nsIURI> uri;
nsresult rv = NS_NewURI(getter_AddRefs(uri), aURL, charset.get(), base);
if (NS_FAILED(rv)) {
NS_WARNING("Failed to create a URI");
return nsnull;
}
nsCAutoString spec;
uri->GetSpec(spec);
if (mPreloadedURLs.Contains(spec)) {
return nsnull;
}
mPreloadedURLs.Put(spec);
return uri.forget();
}
void
nsHtml5TreeOpExecutor::PreloadScript(const nsAString& aURL,
const nsAString& aCharset,
const nsAString& aType)
{
nsCOMPtr<nsIURI> uri = ConvertIfNotPreloadedYet(aURL);
if (!uri) {
return;
}
mDocument->ScriptLoader()->PreloadURI(uri, aCharset, aType);
}
void
nsHtml5TreeOpExecutor::PreloadStyle(const nsAString& aURL,
const nsAString& aCharset)
{
nsCOMPtr<nsIURI> uri = ConvertIfNotPreloadedYet(aURL);
if (!uri) {
return;
}
mDocument->PreloadStyle(uri, aCharset);
}
void
nsHtml5TreeOpExecutor::PreloadImage(const nsAString& aURL,
const nsAString& aCrossOrigin)
{
nsCOMPtr<nsIURI> uri = ConvertIfNotPreloadedYet(aURL);
if (!uri) {
return;
}
mDocument->MaybePreLoadImage(uri, aCrossOrigin);
}
void
nsHtml5TreeOpExecutor::SetSpeculationBase(const nsAString& aURL)
{
if (mSpeculationBaseURI) {
// the first one wins
return;
}
const nsCString& charset = mDocument->GetDocumentCharacterSet();
DebugOnly<nsresult> rv = NS_NewURI(getter_AddRefs(mSpeculationBaseURI), aURL,
charset.get(), mDocument->GetDocumentURI());
NS_WARN_IF_FALSE(NS_SUCCEEDED(rv), "Failed to create a URI");
}
#ifdef DEBUG_NS_HTML5_TREE_OP_EXECUTOR_FLUSH
PRUint32 nsHtml5TreeOpExecutor::sAppendBatchMaxSize = 0;
PRUint32 nsHtml5TreeOpExecutor::sAppendBatchSlotsExamined = 0;
PRUint32 nsHtml5TreeOpExecutor::sAppendBatchExaminations = 0;
PRUint32 nsHtml5TreeOpExecutor::sLongestTimeOffTheEventLoop = 0;
PRUint32 nsHtml5TreeOpExecutor::sTimesFlushLoopInterrupted = 0;
#endif