1999-04-15 20:13:38 +00:00

547 lines
19 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/*
* The contents of this file are subject to the Netscape Public License
* Version 1.0 (the "NPL"); you may not use this file except in
* compliance with the NPL. You may obtain a copy of the NPL at
* http://www.mozilla.org/NPL/
*
* Software distributed under the NPL is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
* for the specific language governing rights and limitations under the
* NPL.
*
* The Initial Developer of this code under the NPL is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All Rights
* Reserved.
*/
/**
* MODULE NOTES:
* @update gess 7/15/98
*
* NavDTD is an implementation of the nsIDTD interface.
* In particular, this class captures the behaviors of the original
* Navigator parser productions.
*
* This DTD, like any other in NGLayout, provides a few basic services:
* - First, the DTD collaborates with the Parser class to convert plain
* text into a sequence of HTMLTokens.
* - Second, the DTD describes containment rules for known elements.
* - Third the DTD controls and coordinates the interaction between the
* parsing system and content sink. (The content sink is the interface
* that serves as a proxy for content model).
* - Fourth the DTD maintains an internal style-stack to handle residual (leaky)
* style tags.
*
* You're most likely working in this class file because
* you want to add or change a behavior inherent in this DTD. The remainder
* of this section will describe what you need to do to affect the kind of
* change you want in this DTD.
*
* RESIDUAL-STYLE HANDLNG:
* There are a number of ways to represent style in an HTML document.
* 1) explicit style tags (<B>, <I> etc)
* 2) implicit styles (like those implicit in <Hn>)
* 3) CSS based styles
*
* Residual style handling results from explicit style tags that are
* not closed. Consider this example: <p>text <b>bold </p>
* When the <p> tag closes, the <b> tag is NOT automatically closed.
* Unclosed style tags are handled by the process we call residual-style
* tag handling.
*
* There are two aspects to residual style tag handling. The first is the
* construction and managing of a stack of residual style tags. The
* second is the automatic emission of residual style tags onto leaf content
* in subsequent portions of the document.This step is necessary to propagate
* the expected style behavior to subsequent portions of the document.
*
* Construction and managing the residual style stack is an inline process that
* occurs during the model building phase of the parse process. During the model-
* building phase of the parse process, a content stack is maintained which tracks
* the open container hierarchy. If a style tag(s) fails to be closed when a normal
* container is closed, that style tag is placed onto the residual style stack. If
* that style tag is subsequently closed (in most contexts), it is popped off the
* residual style stack -- and are of no further concern.
*
* Residual style tag emission occurs when the style stack is not empty, and leaf
* content occurs. In our earlier example, the <b> tag "leaked" out of the <p>
* container. Just before the next leaf is emitted (in this or another container) the
* style tags that are on the stack are emitted in succession. These same residual
* style tags get closed automatically when the leaf's container closes, or if a
* child container is opened.
*
*
*/
#ifndef NS_NAVHTMLDTD__
#define NS_NAVHTMLDTD__
#include "nsIDTD.h"
#include "nsISupports.h"
#include "nsIParser.h"
#include "nsHTMLTokens.h"
#include "nshtmlpars.h"
#include "nsVoidArray.h"
#include "nsDeque.h"
#define NS_INAVHTML_DTD_IID \
{0x5c5cce40, 0xcfd6, 0x11d1, \
{0xaa, 0xda, 0x00, 0x80, 0x5f, 0x8a, 0x3e, 0x14}}
class nsIHTMLContentSink;
class nsIDTDDebug;
class nsIParserNode;
class nsCParserNode;
class CITokenHandler;
class nsParser;
class nsDTDContext;
class nsTagStack;
class nsITokenizer;
/***************************************************************
Now the main event: CNavDTD.
This not so simple class performs all the duties of token
construction and model building. It works in conjunction with
an nsParser.
***************************************************************/
#if defined(XP_PC)
#pragma warning( disable : 4275 )
#endif
CLASS_EXPORT_HTMLPARS CNavDTD : public nsIDTD {
#if defined(XP_PC)
#pragma warning( default : 4275 )
#endif
public:
/**
* Common constructor for navdtd. You probably want to call
* NS_NewNavHTMLDTD().
*
* @update gess 7/9/98
*/
CNavDTD();
/**
* Virtual destructor -- you know what to do
* @update gess 7/9/98
*/
virtual ~CNavDTD();
virtual const nsIID& GetMostDerivedIID(void) const;
/**
* Call this method if you want the DTD to construct a clone of itself.
* @update gess7/23/98
* @param
* @return
*/
virtual nsresult CreateNewInstance(nsIDTD** aInstancePtrResult);
NS_DECL_ISUPPORTS
/**
* This method is called to determine if the given DTD can parse
* a document of a given source-type.
* Note that parsing assumes that the end result will always be stored
* in the main content model. Of course, it's up to you which content-
* model you pass in to the parser, so you can always control the process.
*
* @update gess 7/15/98
* @param aContentType contains the name of a filetype that you are
* being asked to parse).
* @return TRUE if this DTD parse the given type; FALSE otherwise.
*/
virtual eAutoDetectResult CanParse(nsString& aContentType, nsString& aCommand, nsString& aBuffer, PRInt32 aVersion);
/**
* Called by the parser to initiate dtd verification of the
* internal context stack.
* @update gess 7/23/98
* @param
* @return
*/
virtual PRBool Verify(nsString& aURLRef,nsIParser* aParser);
/**
* The parser uses a code sandwich to wrap the parsing process. Before
* the process begins, WillBuildModel() is called. Afterwards the parser
* calls DidBuildModel().
* @update gess5/18/98
* @param aFilename is the name of the file being parsed.
* @return error code (almost always 0)
*/
NS_IMETHOD WillBuildModel(nsString& aFilename,PRBool aNotifySink,nsString& aSourceType,nsIContentSink* aSink=0);
/**
* The parser uses a code sandwich to wrap the parsing process. Before
* the process begins, WillBuildModel() is called. Afterwards the parser
* calls DidBuildModel().
* @update gess5/18/98
* @param aFilename is the name of the file being parsed.
* @return error code (almost always 0)
*/
NS_IMETHOD BuildModel(nsIParser* aParser,nsITokenizer* aTokenizer,nsITokenObserver* anObserver=0,nsIContentSink* aSink=0);
/**
* The parser uses a code sandwich to wrap the parsing process. Before
* the process begins, WillBuildModel() is called. Afterwards the parser
* calls DidBuildModel().
* @update gess5/18/98
* @param anErrorCode contans the last error that occured
* @return error code
*/
NS_IMETHOD DidBuildModel(nsresult anErrorCode,PRBool aNotifySink,nsIParser* aParser,nsIContentSink* aSink=0);
/**
* This method is called by the parser, once for each token
* that has been constructed during the tokenization phase.
* @update gess 3/25/98
* @param aToken -- token object to be put into content model
* @return 0 if all is well; non-zero is an error
*/
NS_IMETHOD HandleToken(CToken* aToken,nsIParser* aParser);
/**
* This method causes all tokens to be dispatched to the given tag handler.
*
* @update gess 3/25/98
* @param aHandler -- object to receive subsequent tokens...
* @return error code (usually 0)
*/
NS_IMETHOD CaptureTokenPump(nsITagHandler* aHandler);
/**
* This method releases the token-pump capture obtained in CaptureTokenPump()
*
* @update gess 3/25/98
* @param aHandler -- object that received tokens...
* @return error code (usually 0)
*/
NS_IMETHOD ReleaseTokenPump(nsITagHandler* aHandler);
/**
*
* @update gess12/28/98
* @param
* @return
*/
nsITokenizer* GetTokenizer(void);
/**
*
* @update gess12/28/98
* @param
* @return
*/
virtual nsITokenRecycler* GetTokenRecycler(void);
/**
* If the parse process gets interrupted, this method gets called
* prior to the process resuming.
* @update gess5/18/98
* @return error code -- usually NS_OK (0)
*/
NS_IMETHOD WillResumeParse(void);
/**
* If the parse process is about to be interrupted, this method
* will be called just prior.
* @update gess5/18/98
* @return error code -- usually NS_OK (0)
*/
NS_IMETHOD WillInterruptParse(void);
virtual void EmitMisplacedContent(nsITokenizer* aTokenizer);
/**
* This method is called to determine whether or not a tag
* of one type can contain a tag of another type.
*
* @update gess 3/25/98
* @param aParent -- int tag of parent container
* @param aChild -- int tag of child container
* @return PR_TRUE if parent can contain child
*/
virtual PRBool CanContain(PRInt32 aParent,PRInt32 aChild) const;
/**
* This method is called to determine whether or not a tag
* of one type can contain a tag of another type.
*
* @update gess 3/25/98
* @param aParent -- int tag of parent container
* @param aChild -- int tag of child container
* @return PR_TRUE if parent can contain child
*/
virtual PRBool CanPropagate(eHTMLTags aParent,eHTMLTags aChild) const;
/**
* This method gets called to determine whether a given
* child tag can be omitted by the given parent.
*
* @update gess 3/25/98
* @param aParent -- parent tag being asked about omitting given child
* @param aChild -- child tag being tested for omittability by parent
* @return PR_TRUE if given tag can be omitted
*/
virtual PRBool CanOmit(eHTMLTags aParent,eHTMLTags aChild)const;
/**
* This is called to determine if the given parent can omit the
* given child (end tag).
*
* @update gess 3/25/98
* @param aParent -- tag type of parent
* @param aChild -- tag type of child
* @return PR_TRUE if given tag can contain omit child (end tag)
*/
virtual PRBool CanOmitEndTag(eHTMLTags aParent,eHTMLTags aChild)const;
/**
* This method gets called to determine whether a given
* tag is itself a container
*
* @update gess 3/25/98
* @param aTag -- tag to test for containership
* @return PR_TRUE if given tag can contain other tags
*/
virtual PRBool IsContainer(PRInt32 aTag) const;
/**
* This method tries to design a context map (without actually
* changing our parser state) from the parent down to the
* child.
*
* @update gess4/6/98
* @param aParent -- tag type of parent
* @param aChild -- tag type of child
* @return True if closure was achieved -- other false
*/
virtual PRBool ForwardPropagate(nsTagStack& aTagStack,eHTMLTags aParentTag,eHTMLTags aChildTag);
/**
* This method tries to design a context map (without actually
* changing our parser state) from the child up to the parent.
*
* @update gess4/6/98
* @param aParent -- tag type of parent
* @param aChild -- tag type of child
* @return True if closure was achieved -- other false
*/
virtual PRBool BackwardPropagate(nsTagStack& aTagStack,eHTMLTags aParentTag,eHTMLTags aChildTag) const;
/**
* Ask parser if a given container is open ANYWHERE on stack
* @update gess5/11/98
* @param id of container you want to test for
* @return TRUE if the given container type is open -- otherwise FALSE
*/
virtual PRBool HasOpenContainer(eHTMLTags aContainer) const;
/**
* Ask parser if a given container is open ANYWHERE on stack
* @update gess5/11/98
* @param id of container you want to test for
* @return TRUE if the given container type is open -- otherwise FALSE
*/
virtual PRBool HasOpenContainer(const eHTMLTags aTagSet[],PRInt32 aCount) const;
/**
* Accessor that retrieves the tag type of the topmost item on context
* vector stack.
*
* @update gess5/11/98
* @return tag type (may be unknown)
*/
virtual eHTMLTags GetTopNode() const;
/**
* Finds the topmost occurance of given tag within context vector stack.
* @update gess5/11/98
* @param tag to be found
* @return index of topmost tag occurance -- may be -1 (kNotFound).
*/
virtual PRInt32 GetTopmostIndexOf(eHTMLTags aTag) const;
/**
* Finds the topmost occurance of given tag within context vector stack.
* @update gess5/11/98
* @param tag to be found
* @return index of topmost tag occurance -- may be -1 (kNotFound).
*/
virtual PRInt32 GetTopmostIndexOf(eHTMLTags aTagSet[],PRInt32 aCount) const;
/**
* The following methods are use to create and manage
* the dynamic set of token handlers.
* @update gess5/11/98
*/
void InitializeDefaultTokenHandlers();
CITokenHandler* GetTokenHandler(eHTMLTokenTypes aType) const;
CITokenHandler* AddTokenHandler(CITokenHandler* aHandler);
void DeleteTokenHandlers(void);
/**
* The following set of methods are used to partially construct
* the content model (via the sink) according to the type of token.
* @update gess5/11/98
* @param aToken is the token (of a given type) to be handled
* @return error code representing construction state; usually 0.
*/
nsresult HandleStartToken(CToken* aToken);
nsresult HandleDefaultStartToken(CToken* aToken,eHTMLTags aChildTag,nsIParserNode& aNode);
nsresult HandleEndToken(CToken* aToken);
nsresult HandleEntityToken(CToken* aToken);
nsresult HandleCommentToken(CToken* aToken);
nsresult HandleSkippedContentToken(CToken* aToken);
nsresult HandleAttributeToken(CToken* aToken);
nsresult HandleScriptToken(nsCParserNode& aNode);
nsresult HandleStyleToken(CToken* aToken);
nsresult HandleProcessingInstructionToken(CToken* aToken);
//*************************************************
//these cover methods mimic the sink, and are used
//by the parser to manage its context-stack.
//*************************************************
/**
* The next set of method open given HTML elements of
* various types.
*
* @update gess5/11/98
* @param node to be opened in content sink.
* @return error code representing error condition-- usually 0.
*/
nsresult OpenHTML(const nsIParserNode& aNode);
nsresult OpenHead(const nsIParserNode& aNode);
nsresult OpenBody(const nsIParserNode& aNode);
nsresult OpenForm(const nsIParserNode& aNode);
nsresult OpenMap(const nsIParserNode& aNode);
nsresult OpenFrameset(const nsIParserNode& aNode);
nsresult OpenContainer(const nsIParserNode& aNode,PRBool aUpdateStyleStack);
/**
* The next set of methods close the given HTML element.
*
* @update gess5/11/98
* @param HTML (node) to be opened in content sink.
* @return error code - 0 if all went well.
*/
nsresult CloseHTML(const nsIParserNode& aNode);
nsresult CloseHead(const nsIParserNode& aNode);
nsresult CloseBody(const nsIParserNode& aNode);
nsresult CloseForm(const nsIParserNode& aNode);
nsresult CloseMap(const nsIParserNode& aNode);
nsresult CloseFrameset(const nsIParserNode& aNode);
nsresult CloseContainer(const nsIParserNode& aNode,eHTMLTags anActualTag,PRBool aUpdateStyles);
/**
* The special purpose methods automatically close
* one or more open containers.
* @update gess5/11/98
* @return error code - 0 if all went well.
*/
nsresult CloseTopmostContainer();
nsresult CloseContainersTo(eHTMLTags aTag,PRBool aUpdateStyles);
nsresult CloseContainersTo(PRInt32 anIndex,eHTMLTags aTag,PRBool aUpdateStyles);
/**
* Causes leaf to be added to sink at current vector pos.
* @update gess5/11/98
* @param aNode is leaf node to be added.
* @return error code - 0 if all went well.
*/
nsresult AddLeaf(const nsIParserNode& aNode);
nsresult AddHeadLeaf(const nsIParserNode& aNode);
/**
* Causes auto-closures of context vector stack in order to find a
* proper home for the given child. Propagation may also occur as
* a fall out.
* @update gess5/11/98
* @param child to be added (somewhere) to context vector stack.
* @return error code - 0 if all went well.
*/
nsresult ReduceContextStackFor(eHTMLTags aChildTag);
/**
* Attempt forward and/or backward propagation for the given
* child within the current context vector stack.
* @update gess5/11/98
* @param type of child to be propagated.
* @return TRUE if succeeds, otherwise FALSE
*/
nsresult CreateContextStackFor(eHTMLTags aChildTag);
/**
* This set of methods is used to create and manage the set of
* transient styles that occur as a result of poorly formed HTML
* or bugs in the original navigator.
*
* @update gess5/11/98
* @param aTag -- represents the transient style tag to be handled.
* @return error code -- usually 0
*/
nsresult OpenTransientStyles(eHTMLTags aTag);
nsresult CloseTransientStyles(eHTMLTags aTag);
nsresult UpdateStyleStackForOpenTag(eHTMLTags aTag,eHTMLTags aActualTag);
nsresult UpdateStyleStackForCloseTag(eHTMLTags aTag,eHTMLTags aActualTag);
PRBool CanContainStyles(eHTMLTags aTag) const;
nsresult DoFragment(PRBool aFlag);
protected:
nsresult CollectAttributes(nsCParserNode& aNode,PRInt32 aCount);
nsresult CollectSkippedContent(nsCParserNode& aNode,PRInt32& aCount);
nsresult WillHandleStartTag(CToken* aToken,eHTMLTags aChildTag,nsCParserNode& aNode);
nsresult DidHandleStartTag(nsCParserNode& aNode,eHTMLTags aChildTag);
nsresult HandleOmittedTag(CToken* aToken,eHTMLTags aChildTag,eHTMLTags aParent,nsIParserNode& aNode);
nsresult HandleSavedTokensAbove(eHTMLTags aTag);
nsIHTMLContentSink* mSink;
CITokenHandler* mTokenHandlers[eToken_last];
nsDTDContext* mHeadContext;
nsDTDContext* mBodyContext;
nsDTDContext* mFormContext;
nsDTDContext* mMapContext;
PRBool mHasOpenForm;
PRBool mHasOpenMap;
PRInt32 mHasOpenHead;
PRBool mHasOpenBody;
PRBool mHadBodyOrFrameset;
nsString mFilename;
nsIDTDDebug* mDTDDebug;
PRInt32 mLineNumber;
nsParser* mParser;
nsITokenizer* mTokenizer;
nsDeque mMisplacedContent;
PRBool mHasOpenScript;
PRBool mSaveBadTokens;
PRUint32 mComputedCRC32;
PRUint32 mExpectedCRC32;
};
extern NS_HTMLPARS nsresult NS_NewNavHTMLDTD(nsIDTD** aInstancePtrResult);
#endif