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Tokenizer and analyzer package supporting precedence prioritized rules

, 1 Jan 2002
A library allowing you to conveniently build a custom tokenizer and analyzer supporting precedence priorized rules
cxtpackagetut_win32vc.zip
cxTokenizer
cxTokenizer.dsp
cxTokenizer.plg
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cxTokenizer.dsp
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stlport_vc645.dll
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cxTokenizer.dsp
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cxTokenizerMatchTokenRule.inl
cxTokenizer.dsp
cxtPackage.dsp
emptyTestApp.clw
emptyTestApp.ico
emptyTestApp.dsp
vssver.scc
cxaToken.inl
cxAnalyzer.dsp
COPYING
cpAbsd.dsw
/*********************************************************************
	Copyright (C) 2001 by

		Alexander Berthold, alexander-berthold@web.de.
		Hoegestr. 54
		79108 Freiburg i. Breisgau
		Germany

    -- This file is part of cxTokenizer --

    "cxTokenizer" is free software; you can redistribute it and/or 
	modify it under the terms of the GNU Lesser General Public 
	License as published by the Free Software Foundation; either 
	version 2 of the License, or any later version.

    "cxTokenizer" is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
	License along with "cxTokenizer"; if not, write to the Free 
	Software  Foundation, Inc., 59 Temple Place, Suite 330, 
	Boston, MA  02111-1307  USA

    ---------------------------------------------------------------
      If you find any bugs or if you make other corrections/
	  enhancements, i'd appreciate if you'd let me know about 
	  that. My email is
  
       alexander-berthold@web.de
  
      If you share this code, do not remove this text.
    ---------------------------------------------------------------

*********************************************************************/

// cxTokenizer.cpp: implementation of the cxTokenizer class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"

#include "cxTokenizerTokenRule.h"
#include "cxTokenizerCharTokenRule.h"
#include "cxTokenizerContextCookie.h"
#include "cxTokenizerContext.h"
#include "cxTokenizerMapData.h"
#include "cxTokenizerMap.h"
#include "cxTokenizerInputStream.h"
#include "cxTokenizer.h"

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif

#include "cxTokenizerDiags.cpp"

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

	cxTokenizer::cxTokenizer(cxTokenizerMap *ptmLexxerMap,
							 cxTokenizerListener *ptlReceiver)
		{
		// ASSERT if any assumption fails
		ASSERT(ptmLexxerMap!=NULL);
		ASSERT(ptlReceiver!=NULL);
		ASSERT(ptmLexxerMap->fCheckValid());
		ASSERT(ptlReceiver->fCheckValid());

		// The input stream must be set later using vSetInputStream
		m_ptisData		=NULL;
		// The tree with the 'path' to the tokens
		m_ptmLexxerMap	=ptmLexxerMap;
		// The listener for the output token stream
		m_ptlReceiver	=ptlReceiver;
		m_tcContextInfo.vClearAllFlags();
		}

	cxTokenizer::cxTokenizer(cxTokenizerInputStream *ptisData,
							 cxTokenizerMap *ptmLexxerMap,
							 cxTokenizerListener *ptlReceiver)
		{
		// ASSERT if any assumption fails
		ASSERT(ptisData!=NULL);
		ASSERT(ptmLexxerMap!=NULL);
		ASSERT(ptlReceiver!=NULL);
		ASSERT(ptisData->fCheckValid());
		ASSERT(ptmLexxerMap->fCheckValid());
		ASSERT(ptlReceiver->fCheckValid());

		// The input stream ...
		m_ptisData		=ptisData;
		// The tree with the 'path' to the tokens
		m_ptmLexxerMap	=ptmLexxerMap;
		// The listener for the output token stream
		m_ptlReceiver	=ptlReceiver;
		m_tcContextInfo.vClearAllFlags();
		}

	cxTokenizer::~cxTokenizer()
		{
		// Delete the input stream if it wants to
		if(m_ptisData)
			{
			// Check validity
			ASSERT(m_ptisData->fCheckValid());

			// Delete?
			if(m_ptisData->fShouldDelete())
				{
				// Yes.
				delete m_ptisData;
				m_ptisData	=NULL;
				}
			}

		// Delete the token listener if it wants to
		if(m_ptlReceiver)
			{
			// Check validity
			ASSERT(m_ptlReceiver->fCheckValid());

			// Delete?
			if(m_ptlReceiver->fShouldDelete())
				{
				// Yes.
				delete m_ptlReceiver;
				m_ptlReceiver	=NULL;
				}
			}
		}

//////////////////////////////////////////////////////////////////////
// Protected internal token recognition operations
//////////////////////////////////////////////////////////////////////

    /*********************************************************************
	    FUNCTION:	cxTokenizer::vRecognizeNonDelimTokens
	    PURPOSE:	Internally called when a non-delimeting token
                    has been recognized. Analyzes the part between
                    the next delimeting token for non-delimeting tokens,
                    and calls vRegisterToken() if anything found.
	    RETURNS:	- void -
    *********************************************************************/
	void	cxTokenizer::vRecognizeNonDelimTokens(std::tstring strTokenText)
		{
		// Is anything to check?
		if(strTokenText.length()==0)
			return;

		// TODO: Extend this function to correctly handle the flag
		// ooptrf_intermediate (currently, only one token is recognized)
		cxTokenizerMapData	*ptmdCurRule = &m_ptmLexxerMap->m_tmdFPRules;
		cxTokenizerMapData	*ptmdNextRule = NULL;
		int					i,len;
		TCHAR				tcChar;
		bool				fComplete = false;

		len					=strTokenText.length();
		for(i=0;i<len;i++)
			{
			tcChar			=strTokenText[i];
			m_tcContextInfo.strGetCurrentText()+=tcChar;

			ptmdNextRule	=ptmdCurRule->ptmdDoesApply(&m_tcContextInfo,tcChar,&fComplete,0,i);
			if(ptmdNextRule==NULL)
				break;

			ptmdNextRule->vApplied(&m_tcContextInfo,tcChar,fComplete,0,i);
			ptmdCurRule		=ptmdNextRule;
			}

		if(ptmdNextRule!=NULL && fComplete)
			{
			std::tstring		strTemp;
			if(ptmdNextRule->pttrGetRule()->fGetResultString(&m_tcContextInfo,strTemp))
				strTokenText=strTemp;

			vRegisterToken(strTokenText,ptmdNextRule->pttrGetRule(),m_ptisData);
			}
		else
			vRegisterToken(strTokenText,NULL,m_ptisData);
		}

    /*********************************************************************
	    FUNCTION:	cxTokenizer::vDelimTokenRecognized
	    PURPOSE:	Internally called when a delimeting token
                    has been recognized. Calls vRecognizeNonDelimTokens()
                    to analyze the part between the last delimeting token
                    and this one. Afterwards registers the token using
                    vRegisterToken().
	    RETURNS:	- void -
    *********************************************************************/
	void	cxTokenizer::vDelimTokenRecognized()
		{
		//	Token has been recognized
		cxTokenizerContext::tc_list_type
								*plstRuleList;
		cxTokenizerContext::cxListEntry
								*pteCur;
		cxTokenizerMapData		*ptmdRule;
		cxTokenizerTokenRule	*pttrDelimTokenRule;
		cxTokenizerContext::rulelist_iterator
								it,cit;
		std::tstring			strDelimToken;
		std::tstring			strBetweenToken;
		std::tstring			strPutBack;

		// There must be exactly one entry in the list of tokens
		plstRuleList		=m_tcContextInfo.plstGetTokenRuleList();
		ASSERT(plstRuleList!=NULL);
		ASSERT(plstRuleList->size()==1);
		if(plstRuleList->size()!=1)
			throw cxTokenizerException(ERR_UNEXPECTED_TOKEN);

		// This one token is the delimeting token
		pteCur				=*plstRuleList->begin();
		ptmdRule			=pteCur->ptmdGetLastValidRule();
		if(ptmdRule->fIsLeaf()==false)
			throw cxTokenizerException(ERR_COMPILER_UNSPECIFIED);

		pttrDelimTokenRule	=ptmdRule->pttrGetRule();
		strDelimToken		=m_tcContextInfo.strGetCurrentText().substr(
								pteCur->nGetStartPosition(),
								pteCur->nGetEndPosition()-pteCur->nGetStartPosition());
		strBetweenToken		=m_tcContextInfo.strGetCurrentText().substr(
								0,
								pteCur->nGetStartPosition());
		strPutBack			=m_tcContextInfo.strGetCurrentText().substr(
								pteCur->nGetEndPosition());

		std::tstring		strTemp;
		if(pttrDelimTokenRule->fGetResultString(&m_tcContextInfo,strTemp))
			strDelimToken	=strTemp;

		// Now parse the text before the delimeting token
		// (can consist of multiple tokens)
		m_tcContextInfo.vCleanUpAfterTokenRecognition();
		vRecognizeNonDelimTokens(strBetweenToken);

		// Register the delimeting token
		vRegisterToken(strDelimToken,pttrDelimTokenRule,m_ptisData);

		// Clean up the parser context
		m_tcContextInfo.vCleanUpAfterTokenRecognition();

		// Put back the remaining characters
		m_ptisData->fPutBack(strPutBack.data());
		}

//////////////////////////////////////////////////////////////////////
// Protected post token recognition operations
//////////////////////////////////////////////////////////////////////

	void	cxTokenizer::vRegisterToken(const std::tstring& strTokenText, 
									    cxTokenizerTokenRule* pttrRule,
										const cxTokenizerInputStream* ptisStream)
		{
		ASSERT(m_ptlReceiver->fCheckValid());
		m_ptlReceiver->vRegisterToken(	strTokenText, pttrRule,
										ptisStream);
		}

//////////////////////////////////////////////////////////////////////
// Protected helper operations
//////////////////////////////////////////////////////////////////////

    /*********************************************************************
	    FUNCTION:	cxTokenizer::pleFindEarliestCompletedToken
	    PURPOSE:	Searches for the rule(token) with the status
                    'completed' and which started earliest
                    (minimal nStartPosition).
	    RETURNS:	cxTokenizerContext::cooListEntry
    *********************************************************************/
    cxTokenizerContext::cxListEntry	
		*cxTokenizer::pteFindEarliestCompletedToken()
		{
		cxTokenizerContext::tc_list_type
							*plstRuleList;
		cxTokenizerContext::rulelist_iterator
							cit;
		plstRuleList		=m_tcContextInfo.plstGetTokenRuleList();

		// Search for the rule which started earliest
		int					nMRPos = 0x7fff;
		cxTokenizerContext::cxListEntry		
							*pteMREntry = NULL;

		for(cit=plstRuleList->begin();cit!=plstRuleList->end();cit++)
			{
			cxTokenizerContext::cxListEntry		
								*pteCur = *cit;

			if(pteCur->fIsMarkedForDeletion())
				continue;

			if(pteCur->fIsCompleted())
				{
				if(pteCur->nGetStartPosition()<nMRPos)
					{
					nMRPos		=pteCur->nGetStartPosition();
					pteMREntry	=pteCur;
					}
				}
			}

		return pteMREntry;
		}

    /*********************************************************************
	    FUNCTION:	cxTokenizer::pleFindEarliestAppliedToken
	    PURPOSE:	Searches for the rule(token) with the status
                    'applied' and which started earliest
                    (minimal nStartPosition).
	    RETURNS:	cxTokenizerContext::cooListEntry
    *********************************************************************/
	cxTokenizerContext::cxListEntry	
		*cxTokenizer::pteFindEarliestAppliedToken()
		{
		cxTokenizerContext::tc_list_type
							*plstRuleList;
		cxTokenizerContext::rulelist_iterator
							cit;
		plstRuleList		=m_tcContextInfo.plstGetTokenRuleList();

		// Search for the rule which started earliest
		int					nMRPos = 0x7fff;
		cxTokenizerContext::cxListEntry		
							*pteMREntry = NULL;

		for(cit=plstRuleList->begin();cit!=plstRuleList->end();cit++)
			{
			cxTokenizerContext::cxListEntry		
								*pteCur = *cit;

			if(pteCur->fIsMarkedForDeletion())
				continue;

			if(pteCur->fIsNotApplying())
				{
				if(pteCur->nGetStartPosition()<nMRPos)
					{
					nMRPos		=pteCur->nGetStartPosition();
					pteMREntry	=pteCur;
					}
				}
			}

		return pteMREntry;
		}

    /*********************************************************************
	    FUNCTION:	cxTokenizer::vMarkAllForDeletionExcept
	    PURPOSE:	Marks all currently used rules for deletion
                    except the one given as an argument.
	    RETURNS:	- void -
    *********************************************************************/
	void	cxTokenizer::vMarkAllForDeletionExcept(const cxTokenizerContext::cxListEntry* pEntry)
		{
		cxTokenizerContext::tc_list_type
							*plstRuleList;
		cxTokenizerContext::rulelist_iterator
							cit;
		plstRuleList		=m_tcContextInfo.plstGetTokenRuleList();

		for(cit=plstRuleList->begin();cit!=plstRuleList->end();cit++)
			{
			cxTokenizerContext::cxListEntry		
								*pteCur = *cit;

			if(pteCur!=pEntry)
				pteCur->vMarkForDeletion();
			}
		}

//////////////////////////////////////////////////////////////////////
// Operations
//////////////////////////////////////////////////////////////////////

    /*********************************************************************
	    FUNCTION:	cxTokenizer::vSetInputStream
	    PURPOSE:	Changes/sets the input stream
	    RETURNS:	- void -
    *********************************************************************/
	void	cxTokenizer::vSetInputStream(cxTokenizerInputStream *pxtisInput)
		{
#ifdef _DEBUG
		if(pxtisInput!=NULL)
			{
			ASSERT(m_ptisData != pxtisInput);
			}
#endif

		if(m_ptisData!=NULL)
			{
			if(m_ptisData->fShouldDelete())
				delete m_ptisData;
			}
		m_ptisData	=pxtisInput;
		}

    /*********************************************************************
	    FUNCTION:	cxTokenizer::vParseCharacter
	    PURPOSE:	Parses the next character from the input stream.
	    RETURNS:	- void -
    *********************************************************************/
	void	cxTokenizer::vParseCharacter(bool fOverrideIsLastChar)
		{
		TCHAR				tcChar;
		bool				fIsLastChar;
		cxTokenizerContext::tc_list_type
							*plstRuleList;
		cxTokenizerContext::rulelist_iterator
							it,cit,dit;
		std::tstring&		strCurrentText = m_tcContextInfo.strGetCurrentText();

		tcChar				=m_ptisData->tcGetNextCharacter();
		fIsLastChar			=m_ptisData->fIsEofReached()?true:fOverrideIsLastChar;
		strCurrentText		+=tcChar;

		plstRuleList		=m_tcContextInfo.plstGetTokenRuleList();
		it					=plstRuleList->begin();

		// The approach is like this:
		// Find the next 'within' token (ignore all characters until this
		// token is found). Then, determine the type of the token in between
		// the starting position and the position where the 'within' token is
		// found

		// 1. Check if already found rules still apply
		int		nCntTotal = 0;
		int		nCntToDelete = 0;
		int		nCntCompleted = 0;
		int		nCntNotApplying = 0;

		for(cit=it;cit!=plstRuleList->end();cit++)
			{
			bool				fSkip = false;
			bool				fComplete = false;
			cxTokenizerContext::cxListEntry		
								*pteCur = *cit;
			cxTokenizerMapData	*ptmdRule = pteCur->ptmdGetRule(), 
								*ptmdRuleNext = NULL;

			nCntTotal++;
			if(pteCur->fIsNotApplying())
				nCntNotApplying++,fSkip=true;
			if(fSkip)
				continue;

			ptmdRuleNext		=ptmdRule->ptmdDoesApply(&m_tcContextInfo,tcChar,&fComplete,pteCur->nGetStartPosition(),strCurrentText.length());
			if(ptmdRuleNext!=NULL)
				{
				ptmdRule->vApplied(&m_tcContextInfo,tcChar,fComplete,pteCur->nGetStartPosition(),strCurrentText.length());

				if(fComplete)
					{
					pteCur->vSetCompleted(	strCurrentText.length(),
											ptmdRuleNext);
					nCntCompleted++;
					}
				pteCur->vSetRule(ptmdRuleNext);
				}
			else
				{
				// NULL -> this char doesn't fit for this rule anymore
				if(pteCur->fIsCompleted())
					{
					pteCur->vSetNotApplying();
					nCntNotApplying++;
					}
				else
					{
					pteCur->vMarkForDeletion();
					nCntToDelete++;
					}
				}
			}

		// Check for new tokens only if in non-exclusive mode
		if(!m_tcContextInfo.fIsFlagSet(tctx_exclusive))
			{
			// 2. Check if any new rules apply for that character
			cxTokenizerMapData	*ptmdNewRule;
			bool				fComplete = false;
			ptmdNewRule			=m_ptmLexxerMap->m_tmdWIRules.ptmdDoesApply(
									&m_tcContextInfo,tcChar,&fComplete,strCurrentText.length(),strCurrentText.length());
			if(ptmdNewRule!=NULL)
				{
				ptmdNewRule->vApplied(&m_tcContextInfo,tcChar,fComplete,strCurrentText.length(),strCurrentText.length());

				// Has the 'exclusive access' flag been set?
				if(m_tcContextInfo.fIsFlagSet(tctx_exclusive))
					{
					// Is this the first character?
					// If yes, we can proceed. If not, we have to complete
					// any open token
					int		len;
					len		=strCurrentText.length();
					if(len!=1)
						{
						// Reset exclusive flag temporarily
						// (will be set again next time)
						m_tcContextInfo.vSetFlag(tctx_exclusive,false);

						TCHAR			tcPB;

						tcPB			=strCurrentText[len-2];
						strCurrentText	=strCurrentText.substr(0,strCurrentText.length()-2);
						m_ptisData->fPutBack(tcChar);
						m_ptisData->fPutBack(tcPB);
						vParseCharacter(true);
						return;
						}
					}

				cxTokenizerContext::cxListEntry	
					*pteNewEntry = new cxTokenizerContext::cxListEntry(
											strCurrentText.length()-1,
											ptmdNewRule);
				if(fComplete)
					{
					pteNewEntry->vSetCompleted(	strCurrentText.length(),
												ptmdNewRule);
					nCntCompleted++;
					}

				plstRuleList->push_front(pteNewEntry);
				nCntTotal++;
				}
			}

		bool	fRecognized = false;

		// More than one rule has been tested?
		if(nCntTotal!=0)
			{
			// Is at least one rule valid?
			if(nCntToDelete!=nCntTotal)
				{
				// Last character found?
				if(fIsLastChar)
					{
					// Search for the rule which started earliest
					cxTokenizerContext::cxListEntry	
						*pteMREntry = pteFindEarliestCompletedToken();
					vMarkAllForDeletionExcept(pteMREntry);
					nCntToDelete	=plstRuleList->size()-1;
					fRecognized		=true;
					}

				// Are all rules which are still valid not applying anymore?
				// (hence completed, but the new character doesn't fit to any
				// of the remaining rules)?
				if( (nCntTotal-nCntToDelete)==nCntNotApplying )
					{
					if( nCntNotApplying==1 )
						{
						// The remaining rule is the result
						fRecognized	=true;
						}
					else
						{
						// Search for the rule which started earliest
						cxTokenizerContext::cxListEntry	
							*pteMREntry = pteFindEarliestAppliedToken();
						vMarkAllForDeletionExcept(pteMREntry);
						nCntToDelete	=plstRuleList->size()-1;
						fRecognized		=true;
						}
					}
				}
			}

		// Delete the rules in the list which are marked for deletion
		VERIFY(m_tcContextInfo.nDeleteMarkedListEntries()==nCntToDelete);

		// Has a rule been recognized?
		if(fRecognized)
			vDelimTokenRecognized();
		else
			{
			if(fIsLastChar)
				{
				std::tstring strTemp = m_tcContextInfo.strGetCurrentTextConst();
				m_tcContextInfo.vCleanUpAfterTokenRecognition();
				vRecognizeNonDelimTokens(strTemp);
				m_tcContextInfo.vCleanUpAfterTokenRecognition();
				}
			}
		}

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Alexander Berthold
Web Developer
Germany Germany
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