core/sql/common/unicode_char_set.h

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// Licensed to the Apache Software Foundation (ASF) under one
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/* -*-C++-*-
 *****************************************************************************
 *
 * File:         unicode_char_set.h
 * RCS:          $Id: 
 * Description:  The implementation of unicode_char_set class
 *
 *
 * Created:      7/8/98
 * Modified:     $ $Date: 2006/11/01 01:38:09 $ (GMT)
 * Language:     C++
 * Status:       $State: Exp $
 *
 *
 *
 *
 *****************************************************************************
 */

#ifndef _UNICODE_CHAR_SET_H
#define _UNICODE_CHAR_SET_H

////////////////////////////////////////////////////////////////////
// 4/10/98  A simple class devoting to the concept of Unicode
////////////////////////////////////////////////////////////////////

#include <string.h>

#include <stddef.h>
#include <limits.h>

#include "Platform.h"

#include "NAWinNT.h"
#include "NABoolean.h"

// Forward declaration
class NAWString;

class unicode_char_set
{
public:

   enum CHAR_CODE_POINTS {SPACE=0x0020, PERCENT=0x0025, UNDERSCORE=0x005F};

   unicode_char_set() {};

   virtual ~unicode_char_set() {};

   static NAWchar to_upper(const NAWchar);

   static void to_upper(NAWchar *, size_t, NAWString &);

static Lng32 to_upper(NAWchar *, Lng32 , NAWchar *, Lng32);

// For full case mapping, an lower case character may map to 
// more than one upper case character
   static NAWchar* to_upper_full(const NAWchar);

   static NAWchar to_lower(const NAWchar);

   static NAWchar space_char() { return unicode_char_set::SPACE; };

   static NAWchar null_char() {return 0;};

   static NAWchar underscore_char() { return unicode_char_set::UNDERSCORE; };

   static NAWchar percent_char() { return unicode_char_set::PERCENT; };

   static NAWchar maxCharValue() { return USHRT_MAX; };

   static short bytesPerChar() { return sizeof(NAWchar); };

   static NABoolean isValidUCS2CodePoint(NAWchar wc)
   {
     UInt32 codePointValue = (UInt32)wc;
     return ( codePointValue < 0xFFFE );
   };

   /*
   *** Comment out the following functions because they are not yet used. ***
     
   // Determines if a NAWchar is a UTF-16 high surrogate code point,
   // ranging from 0xd800 to 0xdbff, inclusive.
   static NABoolean isHighSurrogateCodePoint(NAWchar wc)
   {
     UInt32 codePointValue = (UInt32)wc;
     return ( codePointValue >= 0xD800 && codePointValue <= 0xDBFF );
   }

   // Determines if a character is a UTF-16 low surrogate code point,
   // ranging from 0xdc00 to 0xdfff, inclusive.
   static NABoolean isLowSurrogateCodePoint(NAWchar wc)
   {
     UInt32 codePointValue = (UInt32)wc;
     return ( codePointValue >= 0xDC00 && codePointValue <= 0xDFFF );
   }

   // Determines if the specified code units form a UTF-16 surrogate pair.
   static NABoolean isUTF16SurrogatePair(NAWchar hwc, NAWchar lwc)
   {
     return ( isHighSurrogateCodePoint(hwc) && isLowSurrogateCodePoint(lwc) );
   }

   *** End of commented-out code ***
   */

private:

};

//
// UTF-8 related macro definitions and function declarations
//

#define IS_7_BIT_ASCII_IN_UTF8_CHAR(x)  ((((x) & 0x80) >> 7) == 0)
#define IS_NOT_1ST_BYTE_IN_UTF8_CHAR(x) ((((x) & 0xC0) >> 6) == 2)
#define IS_1ST_BYTE_IN_UTF8_CHAR(x)     ((((x) & 0xC0) >> 6) != 2)

Int32 UTF8CharLenInBytes(const unsigned char firstByteOfTheUtf8Char); // returns 0 on errors

Int32 IndexOfLastByteOfUTF8CharAtOrBeforePos (const unsigned char *utf8Str,
                                              const Int32 utf8StrLenInBytes,
                                              const Int32 bytePos); // returns -1 on errors

Int32 IndexOfFirstByteOfUTF8CharAtOrBeforePos(const unsigned char *utf8Str,
                                              const Int32 utf8StrLenInBytes,
                                              const Int32 bytePos); // returns -1 on errors

#endif