pjs/parser/html/nsHtml5StreamParser.cpp

1167 строки
42 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 "nsHtml5StreamParser.h"
#include "nsICharsetConverterManager.h"
#include "nsICharsetAlias.h"
#include "nsServiceManagerUtils.h"
#include "nsEncoderDecoderUtils.h"
#include "nsContentUtils.h"
#include "nsHtml5Tokenizer.h"
#include "nsIHttpChannel.h"
#include "nsHtml5Parser.h"
#include "nsHtml5TreeBuilder.h"
#include "nsHtml5AtomTable.h"
#include "nsHtml5Module.h"
#include "nsHtml5RefPtr.h"
#include "nsIScriptError.h"
static NS_DEFINE_CID(kCharsetAliasCID, NS_CHARSETALIAS_CID);
PRInt32 nsHtml5StreamParser::sTimerInitialDelay = 120;
PRInt32 nsHtml5StreamParser::sTimerSubsequentDelay = 120;
// static
void
nsHtml5StreamParser::InitializeStatics()
{
nsContentUtils::AddIntPrefVarCache("html5.flushtimer.initialdelay",
&sTimerInitialDelay);
nsContentUtils::AddIntPrefVarCache("html5.flushtimer.subsequentdelay",
&sTimerSubsequentDelay);
}
/*
* 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
* nsHtml5RefPtr. Upon creation, nsHtml5RefPtr addrefs the object it holds
* just like a regular nsRefPtr. This is OK, since the creation of the
* runnable and the nsHtml5RefPtr happens on the main thread.
*
* When the runnable is done on the parser thread, the destructor of
* nsHtml5RefPtr 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_TABLE2(nsHtml5StreamParser,
nsIStreamListener,
nsICharsetDetectionObserver)
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_NSCOMPTR(mObserver)
NS_IMPL_CYCLE_COLLECTION_UNLINK_NSCOMPTR(mRequest)
tmp->mOwner = nsnull;
tmp->mExecutorFlusher = nsnull;
tmp->mLoadFlusher = nsnull;
tmp->mExecutor = nsnull;
NS_IMPL_CYCLE_COLLECTION_UNLINK_NSCOMPTR(mChardet)
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsHtml5StreamParser)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NSCOMPTR(mObserver)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NSCOMPTR(mRequest)
if (tmp->mOwner) {
NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mOwner");
cb.NoteXPCOMChild(static_cast<nsIParser*> (tmp->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));
}
// hack: count self if held by mChardet
if (tmp->mChardet) {
NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb,
"mChardet->mObserver");
cb.NoteXPCOMChild(static_cast<nsIStreamListener*>(tmp));
}
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
class nsHtml5ExecutorFlusher : public nsRunnable
{
private:
nsRefPtr<nsHtml5TreeOpExecutor> mExecutor;
public:
nsHtml5ExecutorFlusher(nsHtml5TreeOpExecutor* aExecutor)
: mExecutor(aExecutor)
{}
NS_IMETHODIMP Run()
{
mExecutor->RunFlushLoop();
return NS_OK;
}
};
class nsHtml5LoadFlusher : public nsRunnable
{
private:
nsRefPtr<nsHtml5TreeOpExecutor> mExecutor;
public:
nsHtml5LoadFlusher(nsHtml5TreeOpExecutor* aExecutor)
: mExecutor(aExecutor)
{}
NS_IMETHODIMP Run()
{
mExecutor->FlushSpeculativeLoads();
return NS_OK;
}
};
nsHtml5StreamParser::nsHtml5StreamParser(nsHtml5TreeOpExecutor* aExecutor,
nsHtml5Parser* aOwner)
: mFirstBuffer(new nsHtml5UTF16Buffer(NS_HTML5_STREAM_PARSER_READ_BUFFER_SIZE))
, mLastBuffer(mFirstBuffer)
, mExecutor(aExecutor)
, mTreeBuilder(new nsHtml5TreeBuilder(mExecutor->GetStage(),
mExecutor->GetStage()))
, mTokenizer(new nsHtml5Tokenizer(mTreeBuilder))
, mTokenizerMutex("nsHtml5StreamParser mTokenizerMutex")
, mOwner(aOwner)
, mSpeculationMutex("nsHtml5StreamParser mSpeculationMutex")
, mTerminatedMutex("nsHtml5StreamParser mTerminatedMutex")
, mThread(nsHtml5Module::GetStreamParserThread())
, mExecutorFlusher(new nsHtml5ExecutorFlusher(aExecutor))
, mLoadFlusher(new nsHtml5LoadFlusher(aExecutor))
, mFlushTimer(do_CreateInstance("@mozilla.org/timer;1"))
{
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
mFlushTimer->SetTarget(mThread);
mAtomTable.Init(); // we aren't checking for OOM anyway...
#ifdef DEBUG
mAtomTable.SetPermittedLookupThread(mThread);
#endif
mTokenizer->setInterner(&mAtomTable);
mTokenizer->setEncodingDeclarationHandler(this);
// Chardet instantiation adapted from nsDOMFile.
// Chardet is initialized here even if it turns out to be useless
// to make the chardet refcount its observer (nsHtml5StreamParser)
// on the main thread.
const nsAdoptingString& detectorName =
nsContentUtils::GetLocalizedStringPref("intl.charset.detector");
if (!detectorName.IsEmpty()) {
nsCAutoString detectorContractID;
detectorContractID.AssignLiteral(NS_CHARSET_DETECTOR_CONTRACTID_BASE);
AppendUTF16toUTF8(detectorName, detectorContractID);
if (mChardet = do_CreateInstance(detectorContractID.get())) {
(void) mChardet->Init(this);
}
}
// There's a zeroing operator new for everything else
}
nsHtml5StreamParser::~nsHtml5StreamParser()
{
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
mTokenizer->end();
NS_ASSERTION(!mFlushTimer, "Flush timer was not dropped before dtor!");
#ifdef DEBUG
mRequest = nsnull;
mObserver = nsnull;
mUnicodeDecoder = nsnull;
mSniffingBuffer = nsnull;
mMetaScanner = nsnull;
mFirstBuffer = nsnull;
mExecutor = nsnull;
mTreeBuilder = nsnull;
mTokenizer = nsnull;
mOwner = nsnull;
#endif
}
nsresult
nsHtml5StreamParser::GetChannel(nsIChannel** aChannel)
{
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
return mRequest ? CallQueryInterface(mRequest, aChannel) :
NS_ERROR_NOT_AVAILABLE;
}
NS_IMETHODIMP
nsHtml5StreamParser::Notify(const char* aCharset, nsDetectionConfident aConf)
{
NS_ASSERTION(IsParserThread(), "Wrong thread!");
if (aConf == eBestAnswer || aConf == eSureAnswer) {
mCharset.Assign(aCharset);
mCharsetSource = kCharsetFromAutoDetection;
mTreeBuilder->SetDocumentCharset(mCharset, mCharsetSource);
}
return NS_OK;
}
nsresult
nsHtml5StreamParser::SetupDecodingAndWriteSniffingBufferAndCurrentSegment(const PRUint8* aFromSegment, // can be null
PRUint32 aCount,
PRUint32* aWriteCount)
{
NS_ASSERTION(IsParserThread(), "Wrong thread!");
nsresult rv = NS_OK;
nsCOMPtr<nsICharsetConverterManager> convManager = do_GetService(NS_CHARSETCONVERTERMANAGER_CONTRACTID, &rv);
NS_ENSURE_SUCCESS(rv, rv);
rv = convManager->GetUnicodeDecoder(mCharset.get(), getter_AddRefs(mUnicodeDecoder));
if (rv == NS_ERROR_UCONV_NOCONV) {
mCharset.AssignLiteral("windows-1252"); // lower case is the raw form
mCharsetSource = kCharsetFromWeakDocTypeDefault;
rv = convManager->GetUnicodeDecoderRaw(mCharset.get(), getter_AddRefs(mUnicodeDecoder));
mTreeBuilder->SetDocumentCharset(mCharset, mCharsetSource);
}
NS_ENSURE_SUCCESS(rv, rv);
mUnicodeDecoder->SetInputErrorBehavior(nsIUnicodeDecoder::kOnError_Recover);
return WriteSniffingBufferAndCurrentSegment(aFromSegment, aCount, aWriteCount);
}
nsresult
nsHtml5StreamParser::WriteSniffingBufferAndCurrentSegment(const PRUint8* aFromSegment, // can be null
PRUint32 aCount,
PRUint32* aWriteCount)
{
NS_ASSERTION(IsParserThread(), "Wrong thread!");
nsresult rv = NS_OK;
if (mSniffingBuffer) {
PRUint32 writeCount;
rv = WriteStreamBytes(mSniffingBuffer, mSniffingLength, &writeCount);
NS_ENSURE_SUCCESS(rv, rv);
mSniffingBuffer = nsnull;
}
mMetaScanner = nsnull;
if (aFromSegment) {
rv = WriteStreamBytes(aFromSegment, aCount, aWriteCount);
}
return rv;
}
nsresult
nsHtml5StreamParser::SetupDecodingFromBom(const char* aCharsetName, const char* aDecoderCharsetName)
{
NS_ASSERTION(IsParserThread(), "Wrong thread!");
nsresult rv = NS_OK;
nsCOMPtr<nsICharsetConverterManager> convManager = do_GetService(NS_CHARSETCONVERTERMANAGER_CONTRACTID, &rv);
NS_ENSURE_SUCCESS(rv, rv);
rv = convManager->GetUnicodeDecoderRaw(aDecoderCharsetName, getter_AddRefs(mUnicodeDecoder));
NS_ENSURE_SUCCESS(rv, rv);
mUnicodeDecoder->SetInputErrorBehavior(nsIUnicodeDecoder::kOnError_Recover);
mCharset.Assign(aCharsetName);
mCharsetSource = kCharsetFromByteOrderMark;
mTreeBuilder->SetDocumentCharset(mCharset, mCharsetSource);
mSniffingBuffer = nsnull;
mMetaScanner = nsnull;
mBomState = BOM_SNIFFING_OVER;
return rv;
}
nsresult
nsHtml5StreamParser::FinalizeSniffing(const PRUint8* aFromSegment, // can be null
PRUint32 aCount,
PRUint32* aWriteCount,
PRUint32 aCountToSniffingLimit)
{
NS_ASSERTION(IsParserThread(), "Wrong thread!");
// meta scan failed.
if (mCharsetSource >= kCharsetFromHintPrevDoc) {
return SetupDecodingAndWriteSniffingBufferAndCurrentSegment(aFromSegment, aCount, aWriteCount);
}
// maybe try chardet now;
if (mChardet) {
nsresult rv;
PRBool dontFeed = PR_FALSE;
if (mSniffingBuffer) {
rv = mChardet->DoIt((const char*)mSniffingBuffer.get(), mSniffingLength, &dontFeed);
NS_ENSURE_SUCCESS(rv, rv);
}
if (!dontFeed && aFromSegment) {
rv = mChardet->DoIt((const char*)aFromSegment, aCountToSniffingLimit, &dontFeed);
NS_ENSURE_SUCCESS(rv, rv);
}
rv = mChardet->Done();
NS_ENSURE_SUCCESS(rv, rv);
// fall thru; callback may have changed charset
}
if (mCharsetSource == kCharsetUninitialized) {
// Hopefully this case is never needed, but dealing with it anyway
mCharset.AssignLiteral("windows-1252");
mCharsetSource = kCharsetFromWeakDocTypeDefault;
mTreeBuilder->SetDocumentCharset(mCharset, mCharsetSource);
}
return SetupDecodingAndWriteSniffingBufferAndCurrentSegment(aFromSegment, aCount, aWriteCount);
}
nsresult
nsHtml5StreamParser::SniffStreamBytes(const PRUint8* aFromSegment,
PRUint32 aCount,
PRUint32* aWriteCount)
{
NS_ASSERTION(IsParserThread(), "Wrong thread!");
nsresult rv = NS_OK;
PRUint32 writeCount;
for (PRUint32 i = 0; i < aCount && mBomState != BOM_SNIFFING_OVER; i++) {
switch (mBomState) {
case BOM_SNIFFING_NOT_STARTED:
NS_ASSERTION(i == 0, "Bad BOM sniffing state.");
switch (*aFromSegment) {
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;
default:
mBomState = BOM_SNIFFING_OVER;
break;
}
break;
case SEEN_UTF_16_LE_FIRST_BYTE:
if (aFromSegment[i] == 0xFE) {
rv = SetupDecodingFromBom("UTF-16", "UTF-16LE"); // upper case is the raw form
NS_ENSURE_SUCCESS(rv, rv);
PRUint32 count = aCount - (i + 1);
rv = WriteStreamBytes(aFromSegment + (i + 1), count, &writeCount);
NS_ENSURE_SUCCESS(rv, rv);
*aWriteCount = writeCount + (i + 1);
return rv;
}
mBomState = BOM_SNIFFING_OVER;
break;
case SEEN_UTF_16_BE_FIRST_BYTE:
if (aFromSegment[i] == 0xFF) {
rv = SetupDecodingFromBom("UTF-16", "UTF-16BE"); // upper case is the raw form
NS_ENSURE_SUCCESS(rv, rv);
PRUint32 count = aCount - (i + 1);
rv = WriteStreamBytes(aFromSegment + (i + 1), count, &writeCount);
NS_ENSURE_SUCCESS(rv, rv);
*aWriteCount = writeCount + (i + 1);
return rv;
}
mBomState = BOM_SNIFFING_OVER;
break;
case SEEN_UTF_8_FIRST_BYTE:
if (aFromSegment[i] == 0xBB) {
mBomState = SEEN_UTF_8_SECOND_BYTE;
} else {
mBomState = BOM_SNIFFING_OVER;
}
break;
case SEEN_UTF_8_SECOND_BYTE:
if (aFromSegment[i] == 0xBF) {
rv = SetupDecodingFromBom("UTF-8", "UTF-8"); // upper case is the raw form
NS_ENSURE_SUCCESS(rv, rv);
PRUint32 count = aCount - (i + 1);
rv = WriteStreamBytes(aFromSegment + (i + 1), count, &writeCount);
NS_ENSURE_SUCCESS(rv, rv);
*aWriteCount = writeCount + (i + 1);
return rv;
}
mBomState = BOM_SNIFFING_OVER;
break;
default:
mBomState = BOM_SNIFFING_OVER;
break;
}
}
// if we get here, there either was no BOM or the BOM sniffing isn't complete yet
if (!mMetaScanner) {
mMetaScanner = new nsHtml5MetaScanner();
}
if (mSniffingLength + aCount >= NS_HTML5_STREAM_PARSER_SNIFFING_BUFFER_SIZE) {
// this is the last buffer
PRUint32 countToSniffingLimit = NS_HTML5_STREAM_PARSER_SNIFFING_BUFFER_SIZE - mSniffingLength;
nsHtml5ByteReadable readable(aFromSegment, aFromSegment + countToSniffingLimit);
mMetaScanner->sniff(&readable, getter_AddRefs(mUnicodeDecoder), mCharset);
if (mUnicodeDecoder) {
mUnicodeDecoder->SetInputErrorBehavior(nsIUnicodeDecoder::kOnError_Recover);
// meta scan successful
mCharsetSource = kCharsetFromMetaPrescan;
mTreeBuilder->SetDocumentCharset(mCharset, mCharsetSource);
mMetaScanner = nsnull;
return WriteSniffingBufferAndCurrentSegment(aFromSegment, aCount, aWriteCount);
}
return FinalizeSniffing(aFromSegment, aCount, aWriteCount, countToSniffingLimit);
}
// not the last buffer
nsHtml5ByteReadable readable(aFromSegment, aFromSegment + aCount);
mMetaScanner->sniff(&readable, getter_AddRefs(mUnicodeDecoder), mCharset);
if (mUnicodeDecoder) {
// meta scan successful
mUnicodeDecoder->SetInputErrorBehavior(nsIUnicodeDecoder::kOnError_Recover);
mCharsetSource = kCharsetFromMetaPrescan;
mTreeBuilder->SetDocumentCharset(mCharset, mCharsetSource);
mMetaScanner = nsnull;
return WriteSniffingBufferAndCurrentSegment(aFromSegment, aCount, aWriteCount);
}
if (!mSniffingBuffer) {
mSniffingBuffer = new PRUint8[NS_HTML5_STREAM_PARSER_SNIFFING_BUFFER_SIZE];
}
memcpy(mSniffingBuffer + mSniffingLength, aFromSegment, aCount);
mSniffingLength += aCount;
*aWriteCount = aCount;
return NS_OK;
}
nsresult
nsHtml5StreamParser::WriteStreamBytes(const PRUint8* aFromSegment,
PRUint32 aCount,
PRUint32* aWriteCount)
{
NS_ASSERTION(IsParserThread(), "Wrong thread!");
// mLastBuffer always points to a buffer of the size NS_HTML5_STREAM_PARSER_READ_BUFFER_SIZE.
if (mLastBuffer->getEnd() == NS_HTML5_STREAM_PARSER_READ_BUFFER_SIZE) {
mLastBuffer = (mLastBuffer->next = new nsHtml5UTF16Buffer(NS_HTML5_STREAM_PARSER_READ_BUFFER_SIZE));
}
PRInt32 totalByteCount = 0;
for (;;) {
PRInt32 end = mLastBuffer->getEnd();
PRInt32 byteCount = aCount - totalByteCount;
PRInt32 utf16Count = NS_HTML5_STREAM_PARSER_READ_BUFFER_SIZE - end;
NS_ASSERTION(utf16Count, "Trying to convert into a buffer with no free space!");
nsresult convResult = mUnicodeDecoder->Convert((const char*)aFromSegment, &byteCount, mLastBuffer->getBuffer() + end, &utf16Count);
end += utf16Count;
mLastBuffer->setEnd(end);
totalByteCount += byteCount;
aFromSegment += byteCount;
NS_ASSERTION(end <= NS_HTML5_STREAM_PARSER_READ_BUFFER_SIZE,
"The Unicode decoder wrote too much data.");
NS_ASSERTION(byteCount >= -1, "The decoder consumed fewer than -1 bytes.");
NS_ASSERTION(byteCount > 0 || NS_FAILED(convResult),
"The decoder consumed too few bytes but did not signal an error.");
if (NS_FAILED(convResult)) {
// Using the more generic NS_FAILED test above in case there are still
// decoders around that don't use NS_ERROR_ILLEGAL_INPUT properly.
NS_ASSERTION(convResult == NS_ERROR_ILLEGAL_INPUT,
"The decoder signaled an error other than NS_ERROR_ILLEGAL_INPUT.");
// There's an illegal byte in the input. It's now the responsibility
// of this calling code to output a U+FFFD REPLACEMENT CHARACTER and
// reset the decoder.
if (totalByteCount < (PRInt32)aCount) {
// advance over the bad byte
++totalByteCount;
++aFromSegment;
} else {
NS_NOTREACHED("The decoder signaled an error but consumed all input.");
// Recovering from this situation in case there are still broken
// decoders, since nsScanner had recovery code, too.
totalByteCount = (PRInt32)aCount;
}
// Emit the REPLACEMENT CHARACTER
mLastBuffer->getBuffer()[end] = 0xFFFD;
++end;
mLastBuffer->setEnd(end);
if (end == NS_HTML5_STREAM_PARSER_READ_BUFFER_SIZE) {
mLastBuffer = mLastBuffer->next = new nsHtml5UTF16Buffer(NS_HTML5_STREAM_PARSER_READ_BUFFER_SIZE);
}
mUnicodeDecoder->Reset();
if (totalByteCount == (PRInt32)aCount) {
*aWriteCount = (PRUint32)totalByteCount;
return NS_OK;
}
} else if (convResult == NS_PARTIAL_MORE_OUTPUT) {
mLastBuffer = mLastBuffer->next = new nsHtml5UTF16Buffer(NS_HTML5_STREAM_PARSER_READ_BUFFER_SIZE);
NS_ASSERTION(totalByteCount < (PRInt32)aCount,
"The Unicode decoder consumed too many bytes.");
} else {
NS_ASSERTION(totalByteCount == (PRInt32)aCount,
"The Unicode decoder consumed the wrong number of bytes.");
*aWriteCount = (PRUint32)totalByteCount;
return NS_OK;
}
}
}
// nsIRequestObserver methods:
nsresult
nsHtml5StreamParser::OnStartRequest(nsIRequest* aRequest, nsISupports* aContext)
{
NS_PRECONDITION(STREAM_NOT_STARTED == mStreamState,
"Got OnStartRequest when the stream had already started.");
NS_PRECONDITION(!mExecutor->HasStarted(),
"Got OnStartRequest at the wrong stage in the executor life cycle.");
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
if (mObserver) {
mObserver->OnStartRequest(aRequest, aContext);
}
mRequest = aRequest;
mStreamState = STREAM_BEING_READ;
PRBool scriptingEnabled = mExecutor->IsScriptEnabled();
mOwner->StartTokenizer(scriptingEnabled);
mTreeBuilder->setScriptingEnabled(scriptingEnabled);
mTokenizer->start();
mExecutor->Start();
mExecutor->StartReadingFromStage();
/*
* 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.
*/
mExecutor->WillBuildModel(eDTDMode_unknown);
nsresult rv = NS_OK;
mReparseForbidden = PR_FALSE;
nsCOMPtr<nsIHttpChannel> httpChannel(do_QueryInterface(mRequest, &rv));
if (NS_SUCCEEDED(rv)) {
nsCAutoString method;
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 = PR_TRUE;
}
}
if (mCharsetSource < kCharsetFromChannel) {
// we aren't ready to commit to an encoding yet
// leave converter uninstantiated for now
return NS_OK;
}
nsCOMPtr<nsICharsetConverterManager> convManager = do_GetService(NS_CHARSETCONVERTERMANAGER_CONTRACTID, &rv);
NS_ENSURE_SUCCESS(rv, rv);
rv = convManager->GetUnicodeDecoder(mCharset.get(), getter_AddRefs(mUnicodeDecoder));
NS_ENSURE_SUCCESS(rv, rv);
mUnicodeDecoder->SetInputErrorBehavior(nsIUnicodeDecoder::kOnError_Recover);
return NS_OK;
}
void
nsHtml5StreamParser::DoStopRequest()
{
NS_ASSERTION(IsParserThread(), "Wrong thread!");
NS_PRECONDITION(STREAM_BEING_READ == mStreamState,
"Stream ended without being open.");
mTokenizerMutex.AssertCurrentThreadOwns();
if (IsTerminated()) {
return;
}
if (!mUnicodeDecoder) {
PRUint32 writeCount;
FinalizeSniffing(nsnull, 0, &writeCount, 0);
// dropped nsresult here
}
mStreamState = STREAM_ENDED;
if (IsTerminatedOrInterrupted()) {
return;
}
ParseAvailableData();
}
class nsHtml5RequestStopper : public nsRunnable
{
private:
nsHtml5RefPtr<nsHtml5StreamParser> mStreamParser;
public:
nsHtml5RequestStopper(nsHtml5StreamParser* aStreamParser)
: mStreamParser(aStreamParser)
{}
NS_IMETHODIMP Run()
{
mozilla::MutexAutoLock autoLock(mStreamParser->mTokenizerMutex);
mStreamParser->DoStopRequest();
return NS_OK;
}
};
nsresult
nsHtml5StreamParser::OnStopRequest(nsIRequest* aRequest,
nsISupports* aContext,
nsresult status)
{
NS_ASSERTION(mRequest == aRequest, "Got Stop on wrong stream.");
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
if (mObserver) {
mObserver->OnStopRequest(aRequest, aContext, status);
}
nsCOMPtr<nsIRunnable> stopper = new nsHtml5RequestStopper(this);
if (NS_FAILED(mThread->Dispatch(stopper, nsIThread::DISPATCH_NORMAL))) {
NS_WARNING("Dispatching StopRequest event failed.");
}
return NS_OK;
}
void
nsHtml5StreamParser::DoDataAvailable(PRUint8* aBuffer, PRUint32 aLength)
{
NS_ASSERTION(IsParserThread(), "Wrong thread!");
NS_PRECONDITION(STREAM_BEING_READ == mStreamState,
"DoDataAvailable called when stream not open.");
mTokenizerMutex.AssertCurrentThreadOwns();
if (IsTerminated()) {
return;
}
PRUint32 writeCount;
HasDecoder() ? WriteStreamBytes(aBuffer, aLength, &writeCount) :
SniffStreamBytes(aBuffer, aLength, &writeCount);
// dropping nsresult here
NS_ASSERTION(writeCount == aLength, "Wrong number of stream bytes written/sniffed.");
if (IsTerminatedOrInterrupted()) {
return;
}
ParseAvailableData();
if (mFlushTimerArmed || mSpeculating) {
return;
}
mFlushTimer->InitWithFuncCallback(nsHtml5StreamParser::TimerCallback,
static_cast<void*> (this),
mFlushTimerEverFired ?
sTimerInitialDelay :
sTimerSubsequentDelay,
nsITimer::TYPE_ONE_SHOT);
mFlushTimerArmed = PR_TRUE;
}
class nsHtml5DataAvailable : public nsRunnable
{
private:
nsHtml5RefPtr<nsHtml5StreamParser> mStreamParser;
nsAutoArrayPtr<PRUint8> mData;
PRUint32 mLength;
public:
nsHtml5DataAvailable(nsHtml5StreamParser* aStreamParser,
PRUint8* aData,
PRUint32 aLength)
: mStreamParser(aStreamParser)
, mData(aData)
, mLength(aLength)
{}
NS_IMETHODIMP Run()
{
mozilla::MutexAutoLock autoLock(mStreamParser->mTokenizerMutex);
mStreamParser->DoDataAvailable(mData, mLength);
return NS_OK;
}
};
// nsIStreamListener method:
nsresult
nsHtml5StreamParser::OnDataAvailable(nsIRequest* aRequest,
nsISupports* aContext,
nsIInputStream* aInStream,
PRUint32 aSourceOffset,
PRUint32 aLength)
{
NS_ASSERTION(mRequest == aRequest, "Got data on wrong stream.");
PRUint32 totalRead;
nsAutoArrayPtr<PRUint8> data(new PRUint8[aLength]);
nsresult rv = aInStream->Read(reinterpret_cast<char*>(data.get()),
aLength, &totalRead);
NS_ENSURE_SUCCESS(rv, rv);
NS_ASSERTION(totalRead <= aLength, "Read more bytes than were available?");
nsCOMPtr<nsIRunnable> dataAvailable = new nsHtml5DataAvailable(this,
data.forget(),
totalRead);
if (NS_FAILED(mThread->Dispatch(dataAvailable, nsIThread::DISPATCH_NORMAL))) {
NS_WARNING("Dispatching DataAvailable event failed.");
}
return rv;
}
void
nsHtml5StreamParser::internalEncodingDeclaration(nsString* aEncoding)
{
// This code needs to stay in sync with
// nsHtml5MetaScanner::tryCharset. Unfortunately, the
// trickery with member fields there leads to some copy-paste reuse. :-(
NS_ASSERTION(IsParserThread(), "Wrong thread!");
if (mCharsetSource >= kCharsetFromMetaTag) { // this threshold corresponds to "confident" in the HTML5 spec
return;
}
if (mReparseForbidden) {
return; // not reparsing even if we wanted to
}
nsCAutoString newEncoding;
CopyUTF16toUTF8(*aEncoding, newEncoding);
// XXX spec says only UTF-16
if (newEncoding.LowerCaseEqualsLiteral("utf-16") ||
newEncoding.LowerCaseEqualsLiteral("utf-16be") ||
newEncoding.LowerCaseEqualsLiteral("utf-16le")) {
newEncoding.Assign("UTF-8");
}
nsresult rv = NS_OK;
nsCOMPtr<nsICharsetAlias> calias(do_GetService(kCharsetAliasCID, &rv));
if (NS_FAILED(rv)) {
NS_NOTREACHED("Charset alias service not available.");
return;
}
PRBool eq;
rv = calias->Equals(newEncoding, mCharset, &eq);
if (NS_FAILED(rv)) {
NS_NOTREACHED("Charset name equality check failed.");
return;
}
if (eq) {
mCharsetSource = kCharsetFromMetaTag; // become confident
return;
}
// XXX check HTML5 non-IANA aliases here
nsCAutoString preferred;
rv = calias->GetPreferred(newEncoding, preferred);
if (NS_FAILED(rv)) {
// the encoding name is bogus
return;
}
if (preferred.LowerCaseEqualsLiteral("utf-16") ||
preferred.LowerCaseEqualsLiteral("utf-16be") ||
preferred.LowerCaseEqualsLiteral("utf-16le") ||
preferred.LowerCaseEqualsLiteral("utf-32") ||
preferred.LowerCaseEqualsLiteral("utf-32be") ||
preferred.LowerCaseEqualsLiteral("utf-32le") ||
preferred.LowerCaseEqualsLiteral("utf-7") ||
preferred.LowerCaseEqualsLiteral("jis_x0212-1990") ||
preferred.LowerCaseEqualsLiteral("x-jis0208") ||
preferred.LowerCaseEqualsLiteral("x-imap4-modified-utf7") ||
preferred.LowerCaseEqualsLiteral("x-user-defined")) {
// Not a rough ASCII superset
return;
}
mTreeBuilder->NeedsCharsetSwitchTo(preferred);
FlushTreeOpsAndDisarmTimer();
Interrupt();
// the tree op executor will cause the stream parser to terminate
// if the charset switch request is accepted or it'll uninterrupt
// if the request failed.
}
void
nsHtml5StreamParser::FlushTreeOpsAndDisarmTimer()
{
NS_ASSERTION(IsParserThread(), "Wrong thread!");
if (mFlushTimerArmed) {
// avoid calling Cancel if the flush timer isn't armed to avoid acquiring
// a mutex
mFlushTimer->Cancel();
mFlushTimerArmed = PR_FALSE;
}
mTreeBuilder->Flush();
if (NS_FAILED(NS_DispatchToMainThread(mExecutorFlusher))) {
NS_WARNING("failed to dispatch executor flush event");
}
}
void
nsHtml5StreamParser::ParseAvailableData()
{
NS_ASSERTION(IsParserThread(), "Wrong thread!");
mTokenizerMutex.AssertCurrentThreadOwns();
if (IsTerminatedOrInterrupted()) {
return;
}
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);
}
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.
if (NS_FAILED(NS_DispatchToMainThread(mLoadFlusher))) {
NS_WARNING("failed to dispatch load flush event");
}
return; // no more data for now but expecting more
case STREAM_ENDED:
if (mAtEOF) {
return;
}
mAtEOF = PR_TRUE;
mTokenizer->eof();
mTreeBuilder->StreamEnded();
FlushTreeOpsAndDisarmTimer();
return; // no more data and not expecting more
default:
NS_NOTREACHED("It should be impossible to reach this.");
return;
}
}
mFirstBuffer = mFirstBuffer->next;
continue;
}
// now we have a non-empty buffer
mFirstBuffer->adjust(mLastWasCR);
mLastWasCR = PR_FALSE;
if (mFirstBuffer->hasMore()) {
mLastWasCR = mTokenizer->tokenizeBuffer(mFirstBuffer);
// At this point, internalEncodingDeclaration() may have called
// Terminate, but that never happens together with script.
// Can't assert that here, though, because it's possible that the main
// thread has called Terminate() while this thread was parsing.
if (mTreeBuilder->HasScript()) {
mozilla::MutexAutoLock speculationAutoLock(mSpeculationMutex);
nsHtml5Speculation* speculation =
new nsHtml5Speculation(mFirstBuffer,
mFirstBuffer->getStart(),
mTokenizer->getLineNumber(),
mTreeBuilder->newSnapshot());
mTreeBuilder->AddSnapshotToScript(speculation->GetSnapshot(),
speculation->GetStartLineNumber());
FlushTreeOpsAndDisarmTimer();
mTreeBuilder->SetOpSink(speculation);
mSpeculations.AppendElement(speculation); // adopts the pointer
mSpeculating = PR_TRUE;
}
if (IsTerminatedOrInterrupted()) {
return;
}
}
continue;
}
}
class nsHtml5StreamParserContinuation : public nsRunnable
{
private:
nsHtml5RefPtr<nsHtml5StreamParser> mStreamParser;
public:
nsHtml5StreamParserContinuation(nsHtml5StreamParser* aStreamParser)
: mStreamParser(aStreamParser)
{}
NS_IMETHODIMP Run()
{
mozilla::MutexAutoLock autoLock(mStreamParser->mTokenizerMutex);
mStreamParser->Uninterrupt();
mStreamParser->ParseAvailableData();
return NS_OK;
}
};
void
nsHtml5StreamParser::ContinueAfterScripts(nsHtml5Tokenizer* aTokenizer,
nsHtml5TreeBuilder* aTreeBuilder,
PRBool aLastWasCR)
{
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
#ifdef DEBUG
mExecutor->AssertStageEmpty();
#endif
PRBool speculationFailed = PR_FALSE;
{
mozilla::MutexAutoLock speculationAutoLock(mSpeculationMutex);
if (mSpeculations.IsEmpty()) {
NS_NOTREACHED("ContinueAfterScripts called without speculations.");
return;
}
nsHtml5Speculation* speculation = mSpeculations.ElementAt(0);
if (aLastWasCR ||
!aTokenizer->isInDataState() ||
!aTreeBuilder->snapshotMatches(speculation->GetSnapshot())) {
speculationFailed = PR_TRUE;
// We've got a failed speculation :-(
Interrupt(); // Make the parser thread release the tokenizer mutex sooner
// 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.
speculation->FlushToSink(mExecutor);
NS_ASSERTION(!mExecutor->IsScriptExecuting(),
"ParseUntilBlocked() was supposed to ensure we don't come "
"here when scripts are executing.");
NS_ASSERTION(mExecutor->IsInFlushLoop(), "How are we here if "
"RunFlushLoop() didn't call ParseUntilBlocked() which is the "
"only caller of this method?");
mSpeculations.RemoveElementAt(0);
return;
}
// else
Interrupt(); // Make the parser thread release the tokenizer mutex sooner
// 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
{
nsCOMPtr<nsIThread> mainThread;
NS_GetMainThread(getter_AddRefs(mainThread));
mAtomTable.SetPermittedLookupThread(mainThread);
}
#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) {
// Rewind the stream
mAtEOF = PR_FALSE;
nsHtml5Speculation* speculation = mSpeculations.ElementAt(0);
mFirstBuffer = speculation->GetBuffer();
mFirstBuffer->setStart(speculation->GetStart());
mTokenizer->setLineNumber(speculation->GetStartLineNumber());
nsContentUtils::ReportToConsole(nsContentUtils::eDOM_PROPERTIES,
"SpeculationFailed",
nsnull, 0,
mExecutor->GetDocument()->GetDocumentURI(),
EmptyString(),
speculation->GetStartLineNumber(),
0,
nsIScriptError::warningFlag,
"DOM Events");
nsHtml5UTF16Buffer* 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 = PR_FALSE;
// Copy state over
mLastWasCR = aLastWasCR;
mTokenizer->loadState(aTokenizer);
mTreeBuilder->loadState(aTreeBuilder, &mAtomTable);
} else {
// We've got a successful speculation and at least a moment ago it was
// the current speculation
mSpeculations.ElementAt(0)->FlushToSink(mExecutor);
NS_ASSERTION(!mExecutor->IsScriptExecuting(),
"ParseUntilBlocked() was supposed to ensure we don't come "
"here when scripts are executing.");
NS_ASSERTION(mExecutor->IsInFlushLoop(), "How are we here if "
"RunFlushLoop() didn't call ParseUntilBlocked() which is the "
"only caller of this method?");
mSpeculations.RemoveElementAt(0);
if (mSpeculations.IsEmpty()) {
// yes, it was still the only speculation. Now stop speculating
if (mTreeBuilder->IsDiscretionaryFlushSafe()) {
// 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);
mTreeBuilder->Flush();
}
mTreeBuilder->SetOpSink(mExecutor->GetStage());
mExecutor->StartReadingFromStage();
mSpeculating = PR_FALSE;
}
}
nsCOMPtr<nsIRunnable> event = new nsHtml5StreamParserContinuation(this);
if (NS_FAILED(mThread->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.SetPermittedLookupThread(mThread);
#endif
}
}
void
nsHtml5StreamParser::ContinueAfterFailedCharsetSwitch()
{
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
nsCOMPtr<nsIRunnable> event = new nsHtml5StreamParserContinuation(this);
if (NS_FAILED(mThread->Dispatch(event, nsIThread::DISPATCH_NORMAL))) {
NS_WARNING("Failed to dispatch nsHtml5StreamParserContinuation");
}
}
class nsHtml5TimerKungFu : public nsRunnable
{
private:
nsHtml5RefPtr<nsHtml5StreamParser> mStreamParser;
public:
nsHtml5TimerKungFu(nsHtml5StreamParser* aStreamParser)
: mStreamParser(aStreamParser)
{}
NS_IMETHODIMP Run()
{
if (mStreamParser->mFlushTimer) {
mStreamParser->mFlushTimer->Cancel();
mStreamParser->mFlushTimer = nsnull;
}
return NS_OK;
}
};
void
nsHtml5StreamParser::DropTimer()
{
NS_ASSERTION(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 nsHtml5RefPtr 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 nsHtml5RefPtr send a runnable back to the main thread to
* release the stream parser.
*/
if (mFlushTimer) {
nsCOMPtr<nsIRunnable> event = new nsHtml5TimerKungFu(this);
if (NS_FAILED(mThread->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()
{
NS_ASSERTION(IsParserThread(), "Wrong thread!");
mozilla::MutexAutoLock autoLock(mTokenizerMutex);
NS_ASSERTION(!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 = PR_FALSE;
mFlushTimerEverFired = PR_TRUE;
if (IsTerminatedOrInterrupted()) {
return;
}
// we aren't speculating and we don't know when new data is
// going to arrive. Send data to the main thread.
// However, don't do if the current element on the stack is a
// foster-parenting element and there's pending text, because flushing in
// that case would make the tree shape dependent on where the flush points
// fall.
if (mTreeBuilder->IsDiscretionaryFlushSafe()) {
if (mTreeBuilder->Flush()) {
if (NS_FAILED(NS_DispatchToMainThread(mExecutorFlusher))) {
NS_WARNING("failed to dispatch executor flush event");
}
}
}
}