nsCharSetProber.h

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/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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 * The Original Code is Mozilla Universal charset detector code.
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 * The Initial Developer of the Original Code is
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 * Portions created by the Initial Developer are Copyright (C) 2001
 * the Initial Developer. All Rights Reserved.
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 * Contributor(s):
 *          Shy Shalom <shooshX@gmail.com>
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#ifndef nsCharSetProber_h__
#define nsCharSetProber_h__

#include "nscore.h"

//#define DEBUG_chardet // Uncomment this for debug dump.

typedef enum {
  eDetecting = 0,   //We are still detecting, no sure answer yet, but caller can ask for confidence.
  eFoundIt = 1,     //That's a positive answer
  eNotMe = 2        //Negative answer
} nsProbingState;

#define SHORTCUT_THRESHOLD      (float)0.95

class nsCharSetProber {
public:
  virtual ~nsCharSetProber() {};
  virtual const char* GetCharSetName() = 0;
  virtual nsProbingState HandleData(const char* aBuf, PRUint32 aLen) = 0;
  virtual nsProbingState GetState(void) = 0;
  virtual void      Reset(void)  = 0;
  virtual float     GetConfidence(void) = 0;
  virtual void      SetOpion() = 0;

#ifdef DEBUG_chardet
  virtual void  DumpStatus() {};
#endif

  // Helper functions used in the Latin1 and Group probers.
  // both functions Allocate a new buffer for newBuf. This buffer should be 
  // freed by the caller using PR_FREEIF.
  // Both functions return PR_FALSE in case of memory allocation failure.
  static PRBool FilterWithoutEnglishLetters(const char* aBuf, PRUint32 aLen, char** newBuf, PRUint32& newLen);
  static PRBool FilterWithEnglishLetters(const char* aBuf, PRUint32 aLen, char** newBuf, PRUint32& newLen);

};

#endif /* nsCharSetProber_h__ */