gecko-dev/parser/htmlparser/nsParser.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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/. */
/**
* MODULE NOTES:
*
* This class does two primary jobs:
* 1) It iterates the tokens provided during the
* tokenization process, identifing where elements
* begin and end (doing validation and normalization).
* 2) It controls and coordinates with an instance of
* the IContentSink interface, to coordinate the
* the production of the content model.
*
* The basic operation of this class assumes that an HTML
* document is non-normalized. Therefore, we don't process
* the document in a normalized way. Don't bother to look
* for methods like: doHead() or doBody().
*
* Instead, in order to be backward compatible, we must
* scan the set of tokens and perform this basic set of
* operations:
* 1) Determine the token type (easy, since the tokens know)
* 2) Determine the appropriate section of the HTML document
* each token belongs in (HTML,HEAD,BODY,FRAMESET).
* 3) Insert content into our document (via the sink) into
* the correct section.
* 4) In the case of tags that belong in the BODY, we must
* ensure that our underlying document state reflects
* the appropriate context for our tag.
*
* For example,if we see a <TR>, we must ensure our
* document contains a table into which the row can
* be placed. This may result in "implicit containers"
* created to ensure a well-formed document.
*
*/
#ifndef NS_PARSER__
#define NS_PARSER__
#include "nsIParser.h"
#include "nsDeque.h"
#include "CParserContext.h"
#include "nsParserCIID.h"
#include "nsITokenizer.h"
#include "nsHTMLTags.h"
#include "nsIContentSink.h"
#include "nsCOMArray.h"
#include "nsCycleCollectionParticipant.h"
#include "nsWeakReference.h"
class nsIDTD;
class nsIRunnable;
#ifdef _MSC_VER
# pragma warning(disable : 4275)
#endif
class nsParser final : public nsIParser,
public nsIStreamListener,
public nsSupportsWeakReference {
/**
* Destructor
* @update gess5/11/98
*/
virtual ~nsParser();
public:
/**
* Called on module init
*/
static nsresult Init();
/**
* Called on module shutdown
*/
static void Shutdown();
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_CYCLE_COLLECTION_CLASS_AMBIGUOUS(nsParser, nsIParser)
/**
* default constructor
* @update gess5/11/98
*/
nsParser();
/**
* Select given content sink into parser for parser output
* @update gess5/11/98
* @param aSink is the new sink to be used by parser
* @return old sink, or nullptr
*/
NS_IMETHOD_(void) SetContentSink(nsIContentSink* aSink) override;
/**
* retrive the sink set into the parser
* @update gess5/11/98
* @param aSink is the new sink to be used by parser
* @return old sink, or nullptr
*/
NS_IMETHOD_(nsIContentSink*) GetContentSink(void) override;
/**
* Call this method once you've created a parser, and want to instruct it
* about the command which caused the parser to be constructed. For example,
* this allows us to select a DTD which can do, say, view-source.
*
* @update gess 3/25/98
* @param aCommand -- ptrs to string that contains command
* @return nada
*/
NS_IMETHOD_(void) GetCommand(nsCString& aCommand) override;
NS_IMETHOD_(void) SetCommand(const char* aCommand) override;
NS_IMETHOD_(void) SetCommand(eParserCommands aParserCommand) override;
/**
* Call this method once you've created a parser, and want to instruct it
* about what charset to load
*
* @update ftang 4/23/99
* @param aCharset- the charset of a document
* @param aCharsetSource- the source of the charset
* @param aChannelHadCharset- ignored
* @return nada
*/
virtual void SetDocumentCharset(NotNull<const Encoding*> aCharset,
int32_t aSource,
bool aChannelHadCharset) override;
NotNull<const Encoding*> GetDocumentCharset(int32_t& aSource) {
aSource = mCharsetSource;
return mCharset;
}
/**
* Cause parser to parse input from given URL
*/
NS_IMETHOD Parse(nsIURI* aURL, void* aKey = nullptr) override;
/**
* This method needs documentation
*/
NS_IMETHOD ParseFragment(const nsAString& aSourceBuffer,
nsTArray<nsString>& aTagStack) override;
/**
* This method gets called when the tokens have been consumed, and it's time
* to build the model via the content sink.
* @update gess5/11/98
* @return YES if model building went well -- NO otherwise.
*/
NS_IMETHOD BuildModel(void) override;
NS_IMETHOD ContinueInterruptedParsing() override;
NS_IMETHOD_(void) BlockParser() override;
NS_IMETHOD_(void) UnblockParser() override;
NS_IMETHOD_(void) ContinueInterruptedParsingAsync() override;
NS_IMETHOD Terminate(void) override;
/**
* Call this to query whether the parser is enabled or not.
*
* @update vidur 4/12/99
* @return current state
*/
NS_IMETHOD_(bool) IsParserEnabled() override;
/**
* Call this to query whether the parser thinks it's done with parsing.
*
* @update rickg 5/12/01
* @return complete state
*/
NS_IMETHOD_(bool) IsComplete() override;
/**
* This rather arcane method (hack) is used as a signal between the
* DTD and the parser. It allows the DTD to tell the parser that content
* that comes through (parser::parser(string)) but not consumed should
* propagate into the next string based parse call.
*
* @update gess 9/1/98
* @param aState determines whether we propagate unused string content.
* @return current state
*/
void SetUnusedInput(nsString& aBuffer);
/**
* This method gets called (automatically) during incremental parsing
* @update gess5/11/98
* @return TRUE if all went well, otherwise FALSE
*/
virtual nsresult ResumeParse(bool allowIteration = true,
bool aIsFinalChunk = false,
bool aCanInterrupt = true);
//*********************************************
// These methods are callback methods used by
// net lib to let us know about our inputstream.
//*********************************************
// nsIRequestObserver methods:
NS_DECL_NSIREQUESTOBSERVER
// nsIStreamListener methods:
NS_DECL_NSISTREAMLISTENER
void PushContext(CParserContext& aContext);
CParserContext* PopContext();
CParserContext* PeekContext() { return mParserContext; }
/**
* Get the channel associated with this parser
* @update harishd,gagan 07/17/01
* @param aChannel out param that will contain the result
* @return NS_OK if successful
*/
NS_IMETHOD GetChannel(nsIChannel** aChannel) override;
/**
* Get the DTD associated with this parser
* @update vidur 9/29/99
* @param aDTD out param that will contain the result
* @return NS_OK if successful, NS_ERROR_FAILURE for runtime error
*/
NS_IMETHOD GetDTD(nsIDTD** aDTD) override;
/**
* Get the nsIStreamListener for this parser
*/
virtual nsIStreamListener* GetStreamListener() override;
void SetSinkCharset(NotNull<const Encoding*> aCharset);
/**
* Removes continue parsing events
* @update kmcclusk 5/18/98
*/
NS_IMETHOD CancelParsingEvents() override;
/**
* Return true.
*/
virtual bool IsInsertionPointDefined() override;
/**
* No-op.
*/
void IncrementScriptNestingLevel() final;
/**
* No-op.
*/
void DecrementScriptNestingLevel() final;
bool HasNonzeroScriptNestingLevel() const final;
/**
* No-op.
*/
virtual void MarkAsNotScriptCreated(const char* aCommand) override;
/**
* Always false.
*/
virtual bool IsScriptCreated() override;
/**
* Set to parser state to indicate whether parsing tokens can be interrupted
* @param aCanInterrupt true if parser can be interrupted, false if it can
* not be interrupted.
* @update kmcclusk 5/18/98
*/
void SetCanInterrupt(bool aCanInterrupt);
/**
* This is called when the final chunk has been
* passed to the parser and the content sink has
* interrupted token processing. It schedules
* a ParserContinue PL_Event which will ask the parser
* to HandleParserContinueEvent when it is handled.
* @update kmcclusk6/1/2001
*/
nsresult PostContinueEvent();
/**
* Fired when the continue parse event is triggered.
* @update kmcclusk 5/18/98
*/
void HandleParserContinueEvent(class nsParserContinueEvent*);
virtual void Reset() override {
Cleanup();
Initialize();
}
bool IsScriptExecuting() { return mSink && mSink->IsScriptExecuting(); }
bool IsOkToProcessNetworkData() {
return !IsScriptExecuting() && !mProcessingNetworkData;
}
protected:
void Initialize(bool aConstructor = false);
void Cleanup();
/**
*
* @update gess5/18/98
* @param
* @return
*/
nsresult WillBuildModel(nsString& aFilename);
/**
*
* @update gess5/18/98
* @param
* @return
*/
nsresult DidBuildModel(nsresult anErrorCode);
private:
/*******************************************
These are the tokenization methods...
*******************************************/
/**
* Part of the code sandwich, this gets called right before
* the tokenization process begins. The main reason for
* this call is to allow the delegate to do initialization.
*
* @update gess 3/25/98
* @param
* @return TRUE if it's ok to proceed
*/
bool WillTokenize(bool aIsFinalChunk = false);
/**
* This is the primary control routine. It iteratively
* consumes tokens until an error occurs or you run out
* of data.
*
* @update gess 3/25/98
* @return error code
*/
nsresult Tokenize(bool aIsFinalChunk = false);
/**
* Pushes XML fragment parsing data to expat without an input stream.
*/
nsresult Parse(const nsAString& aSourceBuffer, void* aKey, bool aLastCall);
protected:
//*********************************************
// And now, some data members...
//*********************************************
CParserContext* mParserContext;
nsCOMPtr<nsIDTD> mDTD;
nsCOMPtr<nsIContentSink> mSink;
nsIRunnable* mContinueEvent; // weak ref
eParserCommands mCommand;
nsresult mInternalState;
nsresult mStreamStatus;
int32_t mCharsetSource;
uint16_t mFlags;
uint32_t mBlocked;
nsString mUnusedInput;
NotNull<const Encoding*> mCharset;
nsCString mCommandStr;
bool mProcessingNetworkData;
bool mIsAboutBlank;
};
nsresult nsParserInitialize();
#endif