rickg 4e262a1fe0 WIP for push based tokenization
git-svn-id: svn://10.0.0.236/trunk@1683 18797224-902f-48f8-a5cc-f745e15eee43
1998-05-14 22:19:08 +00:00

255 lines
7.0 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 4/1/98
*
* The scanner is a low-level service class that knows
* how to consume characters out of an (internal) stream.
* This class also offers a series of utility methods
* that most tokenizers want, such as readUntil(),
* readWhile() and SkipWhite().
*/
#ifndef SCANNER
#define SCANNER
#include "nsString.h"
#include "nsParserTypes.h"
#include "prtypes.h"
#include "nsIInputStream.h"
#include <fstream.h>
class nsIURL;
class ifstream;
class CScanner {
public:
/**
* Use this constructor if you want an incremental (callback)
* based input stream.
*
* @update gess 5/12/98
* @param aMode represents the parser mode (nav, other)
* @return
*/
CScanner(eParseMode aMode=eParseMode_navigator);
/**
* Use this constructor if you want i/o to be based on a
* non-incremental netstream.
*
* @update gess 5/12/98
* @param aMode represents the parser mode (nav, other)
* @return
*/
CScanner(nsIURL* aURL,eParseMode aMode=eParseMode_navigator);
/**
* Use this constructor if you want i/o to be file based.
*
* @update gess 5/12/98
* @param aMode represents the parser mode (nav, other)
* @return
*/
CScanner(const char* aFilename,eParseMode aMode=eParseMode_navigator);
~CScanner();
/**
* retrieve next char from internal input stream
*
* @update gess 3/25/98
* @param ch is the char to accept new value
* @return error code reflecting read status
*/
PRInt32 GetChar(PRUnichar& ch);
/**
* peek ahead to consume next char from scanner's internal
* input buffer
*
* @update gess 3/25/98
* @param ch is the char to accept new value
* @return error code reflecting read status
*/
PRInt32 Peek(PRUnichar& ch);
/**
* Push the given char back onto the scanner
*
* @update gess 3/25/98
* @param character to be pushed
* @return error code
*/
PRInt32 PutBack(PRUnichar ch);
/**
* Skip over chars as long as they're in aSkipSet
*
* @update gess 3/25/98
* @param set of chars to be skipped
* @return error code
*/
PRInt32 SkipOver(nsString& SkipChars);
/**
* Skip over chars as long as they equal given char
*
* @update gess 3/25/98
* @param char to be skipped
* @return error code
*/
PRInt32 SkipOver(PRUnichar aSkipChar);
/**
* Skip over chars as long as they're in aSequence
*
* @update gess 3/25/98
* @param contains sequence to be skipped
* @return error code
*/
PRInt32 SkipPast(nsString& aSequence);
/**
* Skip whitespace on scanner input stream
*
* @update gess 3/25/98
* @return error status
*/
PRInt32 SkipWhite(void);
/**
* Determine if the scanner has reached EOF.
* This method can also cause the buffer to be filled
* if it happens to be empty
*
* @update gess 3/25/98
* @return PR_TRUE upon eof condition
*/
PRInt32 Eof(void);
/**
* Consume characters until you find the terminal char
*
* @update gess 3/25/98
* @param aString receives new data from stream
* @param aTerminal contains terminating char
* @param addTerminal tells us whether to append terminal to aString
* @return error code
*/
PRInt32 ReadUntil(nsString& aString,PRUnichar aTerminal,PRBool addTerminal);
/**
* Consume characters until you find one contained in given
* terminal set.
*
* @update gess 3/25/98
* @param aString receives new data from stream
* @param aTermSet contains set of terminating chars
* @param addTerminal tells us whether to append terminal to aString
* @return error code
*/
PRInt32 ReadUntil(nsString& aString,nsString& aTermSet,PRBool addTerminal);
/**
* Consume characters while they're members of anInputSet
*
* @update gess 3/25/98
* @param aString receives new data from stream
* @param anInputSet contains valid chars
* @param addTerminal tells us whether to append terminal to aString
* @return error code
*/
PRInt32 ReadWhile(nsString& aString,nsString& anInputSet,PRBool addTerminal);
/**
* Records current offset position in input stream. This allows us
* to back up to this point if the need should arise, such as when
* tokenization gets interrupted.
*
* @update gess 5/12/98
* @param
* @return
*/
PRInt32 Mark(void);
/**
* Resets current offset position of input stream to marked position.
* This allows us to back up to this point if the need should arise,
* such as when tokenization gets interrupted.
* NOTE: IT IS REALLY BAD FORM TO CALL RELEASE WITHOUT CALLING MARK FIRST!
*
* @update gess 5/12/98
* @param
* @return
*/
PRInt32 RewindToMark(void);
/**
*
*
* @update gess 5/13/98
* @param
* @return
*/
PRBool Append(nsString& aBuffer);
/**
*
*
* @update gess 5/12/98
* @param
* @return
*/
PRInt32 IncrementalAppend(const char* aBuffer,PRInt32 aSize);
static void SelfTest();
protected:
/**
* Internal method used to cause the internal buffer to
* be filled with data.
*
* @update gess4/3/98
* @param anError is the resulting error code (hopefully 0)
* @return number of new bytes read
*/
PRInt32 FillBuffer(void);
fstream* mFileStream;
nsIInputStream* mNetStream;
nsString mBuffer;
PRInt32 mOffset;
PRInt32 mMarkPos;
PRInt32 mTotalRead;
eParseMode mParseMode;
PRBool mIncremental;
};
#endif