gecko/parser/html/nsHtml5Parser.cpp

704 lines
22 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 "nsContentUtils.h"
#include "nsHtml5Tokenizer.h"
#include "nsHtml5TreeBuilder.h"
#include "nsHtml5Parser.h"
#include "nsHtml5AtomTable.h"
#include "nsHtml5DependentUTF16Buffer.h"
NS_INTERFACE_TABLE_HEAD(nsHtml5Parser)
NS_INTERFACE_TABLE2(nsHtml5Parser, nsIParser, nsISupportsWeakReference)
NS_INTERFACE_TABLE_TO_MAP_SEGUE_CYCLE_COLLECTION(nsHtml5Parser)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTING_ADDREF(nsHtml5Parser)
NS_IMPL_CYCLE_COLLECTING_RELEASE(nsHtml5Parser)
NS_IMPL_CYCLE_COLLECTION_CLASS(nsHtml5Parser)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsHtml5Parser)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NSCOMPTR_AMBIGUOUS(mExecutor,
nsIContentSink)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NSCOMPTR_AMBIGUOUS(mStreamParser,
nsIStreamListener)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsHtml5Parser)
NS_IMPL_CYCLE_COLLECTION_UNLINK_NSCOMPTR(mExecutor)
tmp->DropStreamParser();
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
nsHtml5Parser::nsHtml5Parser()
: mFirstBuffer(new nsHtml5OwningUTF16Buffer((void*)nullptr))
, mLastBuffer(mFirstBuffer)
, mExecutor(new nsHtml5TreeOpExecutor())
, mTreeBuilder(new nsHtml5TreeBuilder(mExecutor, nullptr))
, mTokenizer(new nsHtml5Tokenizer(mTreeBuilder, false))
, mRootContextLineNumber(1)
{
mAtomTable.Init(); // we aren't checking for OOM anyway...
mTokenizer->setInterner(&mAtomTable);
// There's a zeroing operator new for everything else
}
nsHtml5Parser::~nsHtml5Parser()
{
mTokenizer->end();
if (mDocWriteSpeculativeTokenizer) {
mDocWriteSpeculativeTokenizer->end();
}
}
NS_IMETHODIMP_(void)
nsHtml5Parser::SetContentSink(nsIContentSink* aSink)
{
NS_ASSERTION(aSink == static_cast<nsIContentSink*> (mExecutor),
"Attempt to set a foreign sink.");
}
NS_IMETHODIMP_(nsIContentSink*)
nsHtml5Parser::GetContentSink()
{
return static_cast<nsIContentSink*> (mExecutor);
}
NS_IMETHODIMP_(void)
nsHtml5Parser::GetCommand(nsCString& aCommand)
{
aCommand.Assign("view");
}
NS_IMETHODIMP_(void)
nsHtml5Parser::SetCommand(const char* aCommand)
{
NS_ASSERTION(!strcmp(aCommand, "view") ||
!strcmp(aCommand, "view-source") ||
!strcmp(aCommand, "external-resource") ||
!strcmp(aCommand, kLoadAsData),
"Unsupported parser command");
}
NS_IMETHODIMP_(void)
nsHtml5Parser::SetCommand(eParserCommands aParserCommand)
{
NS_ASSERTION(aParserCommand == eViewNormal,
"Parser command was not eViewNormal.");
}
NS_IMETHODIMP_(void)
nsHtml5Parser::SetDocumentCharset(const nsACString& aCharset,
int32_t aCharsetSource)
{
NS_PRECONDITION(!mExecutor->HasStarted(),
"Document charset set too late.");
NS_PRECONDITION(mStreamParser, "Setting charset on a script-only parser.");
nsAutoCString trimmed;
trimmed.Assign(aCharset);
trimmed.Trim(" \t\r\n\f");
mStreamParser->SetDocumentCharset(trimmed, aCharsetSource);
mExecutor->SetDocumentCharsetAndSource(trimmed,
aCharsetSource);
}
NS_IMETHODIMP
nsHtml5Parser::GetChannel(nsIChannel** aChannel)
{
if (mStreamParser) {
return mStreamParser->GetChannel(aChannel);
} else {
return NS_ERROR_NOT_AVAILABLE;
}
}
NS_IMETHODIMP
nsHtml5Parser::GetDTD(nsIDTD** aDTD)
{
*aDTD = nullptr;
return NS_OK;
}
nsIStreamListener*
nsHtml5Parser::GetStreamListener()
{
return mStreamParser;
}
NS_IMETHODIMP
nsHtml5Parser::ContinueInterruptedParsing()
{
NS_NOTREACHED("Don't call. For interface compat only.");
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP_(void)
nsHtml5Parser::BlockParser()
{
mBlocked = true;
}
NS_IMETHODIMP_(void)
nsHtml5Parser::UnblockParser()
{
mBlocked = false;
mExecutor->ContinueInterruptedParsingAsync();
}
NS_IMETHODIMP_(void)
nsHtml5Parser::ContinueInterruptedParsingAsync()
{
mExecutor->ContinueInterruptedParsingAsync();
}
NS_IMETHODIMP_(bool)
nsHtml5Parser::IsParserEnabled()
{
return !mBlocked;
}
NS_IMETHODIMP_(bool)
nsHtml5Parser::IsComplete()
{
return mExecutor->IsComplete();
}
NS_IMETHODIMP
nsHtml5Parser::Parse(nsIURI* aURL,
nsIRequestObserver* aObserver,
void* aKey, // legacy; ignored
nsDTDMode aMode) // legacy; ignored
{
/*
* Do NOT cause WillBuildModel to be called synchronously from here!
* The document won't be ready for it until OnStartRequest!
*/
NS_PRECONDITION(!mExecutor->HasStarted(),
"Tried to start parse without initializing the parser.");
NS_PRECONDITION(mStreamParser,
"Can't call this Parse() variant on script-created parser");
mStreamParser->SetObserver(aObserver);
mStreamParser->SetViewSourceTitle(aURL); // In case we're viewing source
mExecutor->SetStreamParser(mStreamParser);
mExecutor->SetParser(this);
return NS_OK;
}
NS_IMETHODIMP
nsHtml5Parser::Parse(const nsAString& aSourceBuffer,
void* aKey,
const nsACString& aContentType,
bool aLastCall,
nsDTDMode aMode) // ignored
{
nsresult rv;
if (NS_FAILED(rv = mExecutor->IsBroken())) {
return rv;
}
if (aSourceBuffer.Length() > INT32_MAX) {
return mExecutor->MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
}
// Maintain a reference to ourselves so we don't go away
// till we're completely done. The old parser grips itself in this method.
nsCOMPtr<nsIParser> kungFuDeathGrip(this);
// Gripping the other objects just in case, since the other old grip
// required grips to these, too.
nsRefPtr<nsHtml5StreamParser> streamKungFuDeathGrip(mStreamParser);
nsRefPtr<nsHtml5TreeOpExecutor> treeOpKungFuDeathGrip(mExecutor);
if (!mExecutor->HasStarted()) {
NS_ASSERTION(!mStreamParser,
"Had stream parser but document.write started life cycle.");
// This is the first document.write() on a document.open()ed document
mExecutor->SetParser(this);
mTreeBuilder->setScriptingEnabled(mExecutor->IsScriptEnabled());
mTokenizer->start();
mExecutor->Start();
if (!aContentType.EqualsLiteral("text/html")) {
mTreeBuilder->StartPlainText();
mTokenizer->StartPlainText();
}
/*
* 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);
}
// Return early if the parser has processed EOF
if (mExecutor->IsComplete()) {
return NS_OK;
}
if (aLastCall && aSourceBuffer.IsEmpty() && !aKey) {
// document.close()
NS_ASSERTION(!mStreamParser,
"Had stream parser but got document.close().");
if (mDocumentClosed) {
// already closed
return NS_OK;
}
mDocumentClosed = true;
if (!mBlocked && !mInDocumentWrite) {
ParseUntilBlocked();
}
return NS_OK;
}
// If we got this far, we are dealing with a document.write or
// document.writeln call--not document.close().
NS_ASSERTION(IsInsertionPointDefined(),
"Doc.write reached parser with undefined insertion point.");
NS_ASSERTION(!(mStreamParser && !aKey),
"Got a null key in a non-script-created parser");
// XXX is this optimization bogus?
if (aSourceBuffer.IsEmpty()) {
return NS_OK;
}
// This guard is here to prevent document.close from tokenizing synchronously
// while a document.write (that wrote the script that called document.close!)
// is still on the call stack.
mozilla::AutoRestore<bool> guard(mInDocumentWrite);
mInDocumentWrite = true;
// The script is identified by aKey. If there's nothing in the buffer
// chain for that key, we'll insert at the head of the queue.
// When the script leaves something in the queue, a zero-length
// key-holder "buffer" is inserted in the queue. If the same script
// leaves something in the chain again, it will be inserted immediately
// before the old key holder belonging to the same script.
//
// We don't do the actual data insertion yet in the hope that the data gets
// tokenized and there no data or less data to copy to the heap after
// tokenization. Also, this way, we avoid inserting one empty data buffer
// per document.write, which matters for performance when the parser isn't
// blocked and a badly-authored script calls document.write() once per
// input character. (As seen in a benchmark!)
//
// The insertion into the input stream happens conceptually before anything
// gets tokenized. To make sure multi-level document.write works right,
// it's necessary to establish the location of our parser key up front
// in case this is the first write with this key.
//
// In a document.open() case, the first write level has a null key, so that
// case is handled separately, because normal buffers containing data
// have null keys.
// These don't need to be owning references, because they always point to
// the buffer queue and buffers can't be removed from the buffer queue
// before document.write() returns. The buffer queue clean-up happens the
// next time ParseUntilBlocked() is called.
// However, they are made owning just in case the reasoning above is flawed
// and a flaw would lead to worse problems with plain pointers. If this
// turns out to be a perf problem, it's worthwhile to consider making
// prevSearchbuf a plain pointer again.
nsRefPtr<nsHtml5OwningUTF16Buffer> prevSearchBuf;
nsRefPtr<nsHtml5OwningUTF16Buffer> firstLevelMarker;
if (aKey) {
if (mFirstBuffer == mLastBuffer) {
nsHtml5OwningUTF16Buffer* keyHolder = new nsHtml5OwningUTF16Buffer(aKey);
keyHolder->next = mLastBuffer;
mFirstBuffer = keyHolder;
} else if (mFirstBuffer->key != aKey) {
prevSearchBuf = mFirstBuffer;
for (;;) {
if (prevSearchBuf->next == mLastBuffer) {
// key was not found
nsHtml5OwningUTF16Buffer* keyHolder =
new nsHtml5OwningUTF16Buffer(aKey);
keyHolder->next = mFirstBuffer;
mFirstBuffer = keyHolder;
prevSearchBuf = nullptr;
break;
}
if (prevSearchBuf->next->key == aKey) {
// found a key holder
break;
}
prevSearchBuf = prevSearchBuf->next;
}
} // else mFirstBuffer is the keyholder
// prevSearchBuf is the previous buffer before the keyholder or null if
// there isn't one.
} else {
// We have a first-level write in the document.open() case. We insert before
// mLastBuffer, effectively, by making mLastBuffer be a new sentinel object
// and redesignating the previous mLastBuffer as our firstLevelMarker. We
// need to put a marker there, because otherwise additional document.writes
// from nested event loops would insert in the wrong place. Sigh.
mLastBuffer->next = new nsHtml5OwningUTF16Buffer((void*)nullptr);
firstLevelMarker = mLastBuffer;
mLastBuffer = mLastBuffer->next;
}
nsHtml5DependentUTF16Buffer stackBuffer(aSourceBuffer);
while (!mBlocked && stackBuffer.hasMore()) {
stackBuffer.adjust(mLastWasCR);
mLastWasCR = false;
if (stackBuffer.hasMore()) {
int32_t lineNumberSave;
bool inRootContext = (!mStreamParser && !aKey);
if (inRootContext) {
mTokenizer->setLineNumber(mRootContextLineNumber);
} else {
// we aren't the root context, so save the line number on the
// *stack* so that we can restore it.
lineNumberSave = mTokenizer->getLineNumber();
}
mLastWasCR = mTokenizer->tokenizeBuffer(&stackBuffer);
if (inRootContext) {
mRootContextLineNumber = mTokenizer->getLineNumber();
} else {
mTokenizer->setLineNumber(lineNumberSave);
}
if (mTreeBuilder->HasScript()) {
mTreeBuilder->Flush(); // Move ops to the executor
mExecutor->FlushDocumentWrite(); // run the ops
// Flushing tree ops can cause all sorts of things.
// Return early if the parser got terminated.
if (mExecutor->IsComplete()) {
return NS_OK;
}
}
// Ignore suspension requests
}
}
nsRefPtr<nsHtml5OwningUTF16Buffer> heapBuffer;
if (stackBuffer.hasMore()) {
// The buffer wasn't tokenized to completion. Create a copy of the tail
// on the heap.
heapBuffer = stackBuffer.FalliblyCopyAsOwningBuffer();
if (!heapBuffer) {
// Allocation failed. The parser is now broken.
return mExecutor->MarkAsBroken(NS_ERROR_OUT_OF_MEMORY);
}
}
if (heapBuffer) {
// We have something to insert before the keyholder holding in the non-null
// aKey case and we have something to swap into firstLevelMarker in the
// null aKey case.
if (aKey) {
NS_ASSERTION(mFirstBuffer != mLastBuffer,
"Where's the keyholder?");
// the key holder is still somewhere further down the list from
// prevSearchBuf (which may be null)
if (mFirstBuffer->key == aKey) {
NS_ASSERTION(!prevSearchBuf,
"Non-null prevSearchBuf when mFirstBuffer is the key holder?");
heapBuffer->next = mFirstBuffer;
mFirstBuffer = heapBuffer;
} else {
if (!prevSearchBuf) {
prevSearchBuf = mFirstBuffer;
}
// We created a key holder earlier, so we will find it without walking
// past the end of the list.
while (prevSearchBuf->next->key != aKey) {
prevSearchBuf = prevSearchBuf->next;
}
heapBuffer->next = prevSearchBuf->next;
prevSearchBuf->next = heapBuffer;
}
} else {
NS_ASSERTION(firstLevelMarker, "How come we don't have a marker.");
firstLevelMarker->Swap(heapBuffer);
}
}
if (!mBlocked) { // buffer was tokenized to completion
NS_ASSERTION(!stackBuffer.hasMore(),
"Buffer wasn't tokenized to completion?");
// Scripting semantics require a forced tree builder flush here
mTreeBuilder->Flush(); // Move ops to the executor
mExecutor->FlushDocumentWrite(); // run the ops
} else if (stackBuffer.hasMore()) {
// The buffer wasn't tokenized to completion. Tokenize the untokenized
// content in order to preload stuff. This content will be retokenized
// later for normal parsing.
if (!mDocWriteSpeculatorActive) {
mDocWriteSpeculatorActive = true;
if (!mDocWriteSpeculativeTreeBuilder) {
// Lazily initialize if uninitialized
mDocWriteSpeculativeTreeBuilder =
new nsHtml5TreeBuilder(nullptr, mExecutor->GetStage());
mDocWriteSpeculativeTreeBuilder->setScriptingEnabled(
mTreeBuilder->isScriptingEnabled());
mDocWriteSpeculativeTokenizer =
new nsHtml5Tokenizer(mDocWriteSpeculativeTreeBuilder, false);
mDocWriteSpeculativeTokenizer->setInterner(&mAtomTable);
mDocWriteSpeculativeTokenizer->start();
}
mDocWriteSpeculativeTokenizer->resetToDataState();
mDocWriteSpeculativeTreeBuilder->loadState(mTreeBuilder, &mAtomTable);
mDocWriteSpeculativeLastWasCR = false;
}
// Note that with multilevel document.write if we didn't just activate the
// speculator, it's possible that the speculator is now in the wrong state.
// That's OK for the sake of simplicity. The worst that can happen is
// that the speculative loads aren't exactly right. The content will be
// reparsed anyway for non-preload purposes.
// The buffer position for subsequent non-speculative parsing now lives
// in heapBuffer, so it's ok to let the buffer position of stackBuffer
// to be overwritten and not restored below.
while (stackBuffer.hasMore()) {
stackBuffer.adjust(mDocWriteSpeculativeLastWasCR);
if (stackBuffer.hasMore()) {
mDocWriteSpeculativeLastWasCR =
mDocWriteSpeculativeTokenizer->tokenizeBuffer(&stackBuffer);
}
}
mDocWriteSpeculativeTreeBuilder->Flush();
mDocWriteSpeculativeTreeBuilder->DropHandles();
mExecutor->FlushSpeculativeLoads();
}
return NS_OK;
}
NS_IMETHODIMP
nsHtml5Parser::Terminate()
{
// We should only call DidBuildModel once, so don't do anything if this is
// the second time that Terminate has been called.
if (mExecutor->IsComplete()) {
return NS_OK;
}
// XXX - [ until we figure out a way to break parser-sink circularity ]
// Hack - Hold a reference until we are completely done...
nsCOMPtr<nsIParser> kungFuDeathGrip(this);
nsRefPtr<nsHtml5StreamParser> streamKungFuDeathGrip(mStreamParser);
nsRefPtr<nsHtml5TreeOpExecutor> treeOpKungFuDeathGrip(mExecutor);
if (mStreamParser) {
mStreamParser->Terminate();
}
return mExecutor->DidBuildModel(true);
}
NS_IMETHODIMP
nsHtml5Parser::ParseFragment(const nsAString& aSourceBuffer,
nsTArray<nsString>& aTagStack)
{
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP
nsHtml5Parser::BuildModel()
{
NS_NOTREACHED("Don't call this!");
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP
nsHtml5Parser::CancelParsingEvents()
{
NS_NOTREACHED("Don't call this!");
return NS_ERROR_NOT_IMPLEMENTED;
}
void
nsHtml5Parser::Reset()
{
NS_NOTREACHED("Don't call this!");
}
bool
nsHtml5Parser::CanInterrupt()
{
// nsContentSink needs this to let nsContentSink::DidProcessATokenImpl
// interrupt.
return true;
}
bool
nsHtml5Parser::IsInsertionPointDefined()
{
return !mExecutor->IsFlushing() &&
(!mStreamParser || mParserInsertedScriptsBeingEvaluated);
}
void
nsHtml5Parser::BeginEvaluatingParserInsertedScript()
{
++mParserInsertedScriptsBeingEvaluated;
}
void
nsHtml5Parser::EndEvaluatingParserInsertedScript()
{
--mParserInsertedScriptsBeingEvaluated;
}
void
nsHtml5Parser::MarkAsNotScriptCreated(const char* aCommand)
{
NS_PRECONDITION(!mStreamParser, "Must not call this twice.");
eParserMode mode = NORMAL;
if (!nsCRT::strcmp(aCommand, "view-source")) {
mode = VIEW_SOURCE_HTML;
} else if (!nsCRT::strcmp(aCommand, "view-source-xml")) {
mode = VIEW_SOURCE_XML;
} else if (!nsCRT::strcmp(aCommand, "view-source-plain")) {
mode = VIEW_SOURCE_PLAIN;
} else if (!nsCRT::strcmp(aCommand, "plain-text")) {
mode = PLAIN_TEXT;
} else if (!nsCRT::strcmp(aCommand, kLoadAsData)) {
mode = LOAD_AS_DATA;
}
#ifdef DEBUG
else {
NS_ASSERTION(!nsCRT::strcmp(aCommand, "view") ||
!nsCRT::strcmp(aCommand, "external-resource"),
"Unsupported parser command!");
}
#endif
mStreamParser = new nsHtml5StreamParser(mExecutor, this, mode);
}
bool
nsHtml5Parser::IsScriptCreated()
{
return !mStreamParser;
}
/* End nsIParser */
// not from interface
void
nsHtml5Parser::ParseUntilBlocked()
{
if (mBlocked || mExecutor->IsComplete() || NS_FAILED(mExecutor->IsBroken())) {
return;
}
NS_ASSERTION(mExecutor->HasStarted(), "Bad life cycle.");
NS_ASSERTION(!mInDocumentWrite,
"ParseUntilBlocked entered while in doc.write!");
mDocWriteSpeculatorActive = false;
for (;;) {
if (!mFirstBuffer->hasMore()) {
if (mFirstBuffer == mLastBuffer) {
if (mExecutor->IsComplete()) {
// something like cache manisfests stopped the parse in mid-flight
return;
}
if (mDocumentClosed) {
NS_ASSERTION(!mStreamParser,
"This should only happen with script-created parser.");
mTokenizer->eof();
mTreeBuilder->StreamEnded();
mTreeBuilder->Flush();
mExecutor->FlushDocumentWrite();
mTokenizer->end();
return;
}
// never release the last buffer.
NS_ASSERTION(!mLastBuffer->getStart() && !mLastBuffer->getEnd(),
"Sentinel buffer had its indeces changed.");
if (mStreamParser) {
if (mReturnToStreamParserPermitted &&
!mExecutor->IsScriptExecuting()) {
mTreeBuilder->Flush();
mReturnToStreamParserPermitted = false;
mStreamParser->ContinueAfterScripts(mTokenizer,
mTreeBuilder,
mLastWasCR);
}
} else {
// Script-created parser
mTreeBuilder->Flush();
// No need to flush the executor, because the executor is already
// in a flush
NS_ASSERTION(mExecutor->IsInFlushLoop(),
"How did we come here without being in the flush loop?");
}
return; // no more data for now but expecting more
}
mFirstBuffer = mFirstBuffer->next;
continue;
}
if (mBlocked || mExecutor->IsComplete()) {
return;
}
// now we have a non-empty buffer
mFirstBuffer->adjust(mLastWasCR);
mLastWasCR = false;
if (mFirstBuffer->hasMore()) {
bool inRootContext = (!mStreamParser && !mFirstBuffer->key);
if (inRootContext) {
mTokenizer->setLineNumber(mRootContextLineNumber);
}
mLastWasCR = mTokenizer->tokenizeBuffer(mFirstBuffer);
if (inRootContext) {
mRootContextLineNumber = mTokenizer->getLineNumber();
}
if (mTreeBuilder->HasScript()) {
mTreeBuilder->Flush();
mExecutor->FlushDocumentWrite();
}
if (mBlocked) {
return;
}
}
continue;
}
}
nsresult
nsHtml5Parser::Initialize(nsIDocument* aDoc,
nsIURI* aURI,
nsISupports* aContainer,
nsIChannel* aChannel)
{
return mExecutor->Init(aDoc, aURI, aContainer, aChannel);
}
void
nsHtml5Parser::StartTokenizer(bool aScriptingEnabled) {
mTreeBuilder->SetPreventScriptExecution(!aScriptingEnabled);
mTreeBuilder->setScriptingEnabled(aScriptingEnabled);
mTokenizer->start();
}
void
nsHtml5Parser::InitializeDocWriteParserState(nsAHtml5TreeBuilderState* aState,
int32_t aLine)
{
mTokenizer->resetToDataState();
mTokenizer->setLineNumber(aLine);
mTreeBuilder->loadState(aState, &mAtomTable);
mLastWasCR = false;
mReturnToStreamParserPermitted = true;
}
void
nsHtml5Parser::ContinueAfterFailedCharsetSwitch()
{
NS_PRECONDITION(mStreamParser,
"Tried to continue after failed charset switch without a stream parser");
mStreamParser->ContinueAfterFailedCharsetSwitch();
}