stringex.h

C++ patterns设计模式

    //typedef codecvt<wchar_t, char, mbstate_t> SSCodeCvt;
// =============================================================================
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------

	inline PWSTR StdCodeCvt(PWSTR pDstW, int nDst, PCSTR pSrcA, int nSrc,
        const std::locale& loc=std::locale())
    {

        ASSERT(0 != pSrcA);
        ASSERT(0 != pDstW);

		pDstW[0]					= '\0';	

		if ( nSrc > 0 )
		{
			PCSTR pNextSrcA			= pSrcA;
			PWSTR pNextDstW			= pDstW;
			SSCodeCvt::result res	= SSCodeCvt::ok;
			const SSCodeCvt& conv	= SS_USE_FACET(loc, SSCodeCvt);
			SSCodeCvt::state_type st= { 0 };
			res						= conv.in(st,
										pSrcA, pSrcA + nSrc, pNextSrcA,
										pDstW, pDstW + nDst, pNextDstW);

			ASSERT(SSCodeCvt::ok == res);
			ASSERT(SSCodeCvt::error != res);
			ASSERT(pNextDstW >= pDstW);
			ASSERT(pNextSrcA >= pSrcA);

			// Null terminate the converted string

			if ( pNextDstW - pDstW > nDst )
				*(pDstW + nDst) = '\0';
			else
				*pNextDstW = '\0';
		}
        return pDstW;
    }
    inline PWSTR StdCodeCvt(PWSTR pDstW, int nDst, PCUSTR pSrcA, int nSrc,
        const std::locale& loc=std::locale())
    {
        return StdCodeCvt(pDstW, nDst, (PCSTR)pSrcA, nSrc, loc);
    }

    inline PSTR StdCodeCvt(PSTR pDstA, int nDst, PCWSTR pSrcW, int nSrc,
        const std::locale& loc=std::locale())
    {
        ASSERT(0 != pDstA);
        ASSERT(0 != pSrcW);

		pDstA[0]					= '\0';	

		if ( nSrc > 0 )
		{
			PSTR pNextDstA			= pDstA;
			PCWSTR pNextSrcW		= pSrcW;
			SSCodeCvt::result res	= SSCodeCvt::ok;
			const SSCodeCvt& conv	= SS_USE_FACET(loc, SSCodeCvt);
			SSCodeCvt::state_type st= { 0 };
			res						= conv.out(st,
										pSrcW, pSrcW + nDst, pNextSrcW,
										pDstA, pDstA + nSrc, pNextDstA);

			ASSERT(SSCodeCvt::error != res);
			ASSERT(SSCodeCvt::ok == res);	// strict, comment out for sanity
			ASSERT(pNextDstA >= pDstA);
			ASSERT(pNextSrcW >= pSrcW);

			// Null terminate the converted string

			if ( pNextDstA - pDstA > nDst )
				*(pDstA + nDst) = '\0';
			else
				*pNextDstA = '\0';
		}
        return pDstA;
    }
    inline PUSTR StdCodeCvt(PUSTR pDstA, int nDst, PCWSTR pSrcW, int nSrc,
        const std::locale& loc=std::locale())
    {
        return (PUSTR)StdCodeCvt((PSTR)pDstA, nDst, pSrcW, nSrc, loc);
    }
/*
#else   // ...or are we doing things assuming win32 and Visual C++?

	inline PWSTR StdCodeCvt(PWSTR pDstW, int nDst, PCSTR pSrcA, int nSrc, UINT acp=CP_ACP)
	{
		ASSERT(0 != pSrcA);
		ASSERT(0 != pDstW);
		pW[0] = '\0';
		MultiByteToWideChar(acp, 0, pSrcA, nSrc, pDstW, nDst);
		return pW;
	}
	inline PWSTR StdCodeCvt(PWSTR pDstW, nDst, PCUSTR pSrcA, int nSrc, UINT acp=CP_ACP)
	{
		return StdCodeCvt(pDstW, nDst, (PCSTR)pSrcA, nSrc, acp);
	}

	inline PSTR StdCodeCvt(PSTR pDstA, nDst PCWSTR pSrcW, int nSrc, UINT acp=CP_ACP)
	{
		ASSERT(0 != pDstA);
		ASSERT(0 != pSrcW);
		pA[0] = '\0';
		WideCharToMultiByte(acp, 0, pSrcW, nSrc, pDstA, nDst, 0, 0);
		return pA;
	}
	inline PUSTR StdCodeCvt(PUSTR pDstA, nDst, PCWSTR pSrcW, int nSrc, UINT acp=CP_ACP)
	{
		return (PUSTR)StdCodeCvt((PSTR)pDstA, nDst, pSrcW, nSrc, acp);
	}

#endif
*/

// Unicode/MBCS conversion macros are only available on implementations of
// the "C" library that have the non-standard _alloca function.  As far as I
// know that's only Microsoft's though I've hear that the function exits
// elsewhere.  
    
#if defined(SS_ALLOCA) && !defined SS_NO_CONVERSION

    #include <malloc.h>	// needed for _alloca

    // Define our conversion macros to look exactly like Microsoft's to
    // facilitate using this stuff both with and without MFC/ATL

    #ifdef _CONVERSION_USES_THREAD_LOCALE

	    #ifndef _DEBUG
		    #define SSCVT int _cvt; _cvt; UINT _acp=GetACP(); \
			    _acp; PCWSTR _pw; _pw; PCSTR _pa; _pa
	    #else
		    #define SSCVT int _cvt = 0; _cvt; UINT _acp=GetACP();\
			     _acp; PCWSTR _pw=0; _pw; PCSTR _pa=0; _pa
	    #endif
	    #define SSA2W(pa) (\
		    ((_pa = pa) == 0) ? 0 : (\
			    _cvt = (sslen(_pa)),\
			    StdCodeCvt((PWSTR) _alloca((_cvt+1)*2), (_cvt+1)*2, \
							_pa, _cvt, _acp)))
	    #define SSW2A(pw) (\
		    ((_pw = pw) == 0) ? 0 : (\
			    _cvt = sslen(_pw), \
			    StdCodeCvt((LPSTR) _alloca((_cvt+1)*2), (_cvt+1)*2, \
					_pw, _cvt, _acp)))
	#else

	    #ifndef _DEBUG
		    #define SSCVT int _cvt; _cvt; UINT _acp=CP_ACP; _acp;\
			     PCWSTR _pw; _pw; PCSTR _pa; _pa
	    #else
		    #define SSCVT int _cvt = 0; _cvt; UINT _acp=CP_ACP; \
			    _acp; PCWSTR _pw=0; _pw; PCSTR _pa=0; _pa
	    #endif
	    #define SSA2W(pa) (\
		    ((_pa = pa) == 0) ? 0 : (\
			    _cvt = (sslen(_pa)),\
			    StdCodeCvt((PWSTR) _alloca((_cvt+1)*2), (_cvt+1)*2, \
					_pa, _cvt)))
	    #define SSW2A(pw) (\
		    ((_pw = pw) == 0) ? 0 : (\
			    _cvt = (sslen(_pw)),\
			    StdCodeCvt((LPSTR) _alloca((_cvt+1)*2), (_cvt+1)*2, \
					_pw, _cvt)))
    #endif

    #define SSA2CW(pa) ((PCWSTR)SSA2W((pa)))
    #define SSW2CA(pw) ((PCSTR)SSW2A((pw)))

    #ifdef UNICODE
	    #define SST2A	SSW2A
	    #define SSA2T	SSA2W
	    #define SST2CA	SSW2CA
	    #define SSA2CT	SSA2CW
		// (Did you get a compiler error here about not being able to convert
		// PTSTR into PWSTR?  Then your _UNICODE and UNICODE flags are messed 
		// up.  Best bet: #define BOTH macros before including any MS headers.)
	    inline PWSTR	SST2W(PTSTR p)			{ return p; }
	    inline PTSTR	SSW2T(PWSTR p)			{ return p; }
	    inline PCWSTR	SST2CW(PCTSTR p)		{ return p; }
	    inline PCTSTR	SSW2CT(PCWSTR p)		{ return p; }
    #else
	    #define SST2W	SSA2W
	    #define SSW2T	SSW2A
	    #define SST2CW	SSA2CW
	    #define SSW2CT	SSW2CA
	    inline PSTR		SST2A(PTSTR p)			{ return p; }
	    inline PTSTR	SSA2T(PSTR p)			{ return p; }
	    inline PCSTR	SST2CA(PCTSTR p)		{ return p; }
	    inline PCTSTR	SSA2CT(PCSTR p)			{ return p; }
    #endif // #ifdef UNICODE

    #if defined(UNICODE)
    // in these cases the default (TCHAR) is the same as OLECHAR
	    inline PCOLESTR	SST2COLE(PCTSTR p)		{ return p; }
	    inline PCTSTR	SSOLE2CT(PCOLESTR p)	{ return p; }
	    inline POLESTR	SST2OLE(PTSTR p)		{ return p; }
	    inline PTSTR	SSOLE2T(POLESTR p)		{ return p; }
    #elif defined(OLE2ANSI)
    // in these cases the default (TCHAR) is the same as OLECHAR
	    inline PCOLESTR	SST2COLE(PCTSTR p)		{ return p; }
	    inline PCTSTR	SSOLE2CT(PCOLESTR p)	{ return p; }
	    inline POLESTR	SST2OLE(PTSTR p)		{ return p; }
	    inline PTSTR	SSOLE2T(POLESTR p)		{ return p; }
    #else
	    //CharNextW doesn't work on Win95 so we use this
	    #define SST2COLE(pa)	SSA2CW((pa))
	    #define SST2OLE(pa)		SSA2W((pa))
	    #define SSOLE2CT(po)	SSW2CA((po))
	    #define SSOLE2T(po)		SSW2A((po))
    #endif

    #ifdef OLE2ANSI
	    #define SSW2OLE		SSW2A
	    #define SSOLE2W		SSA2W
	    #define SSW2COLE	SSW2CA
	    #define SSOLE2CW	SSA2CW
	    inline POLESTR		SSA2OLE(PSTR p)		{ return p; }
	    inline PSTR			SSOLE2A(POLESTR p)	{ return p; }
	    inline PCOLESTR		SSA2COLE(PCSTR p)	{ return p; }
	    inline PCSTR		SSOLE2CA(PCOLESTR p){ return p; }
    #else
	    #define SSA2OLE		SSA2W
	    #define SSOLE2A		SSW2A
	    #define SSA2COLE	SSA2CW
	    #define SSOLE2CA	SSW2CA
	    inline POLESTR		SSW2OLE(PWSTR p)	{ return p; }
	    inline PWSTR		SSOLE2W(POLESTR p)	{ return p; }
	    inline PCOLESTR		SSW2COLE(PCWSTR p)	{ return p; }
	    inline PCWSTR		SSOLE2CW(PCOLESTR p){ return p; }
    #endif

    // Above we've defined macros that look like MS' but all have
    // an 'SS' prefix.  Now we need the real macros.  We'll either
    // get them from the macros above or from MFC/ATL. 

	#if defined (USES_CONVERSION)

		#define _NO_STDCONVERSION	// just to be consistent

	#else

		#ifdef _MFC_VER

			#include <afxconv.h>
			#define _NO_STDCONVERSION // just to be consistent

		#else

			#define USES_CONVERSION SSCVT
			#define A2CW			SSA2CW
			#define W2CA			SSW2CA
			#define T2A				SST2A
			#define A2T				SSA2T
			#define T2W				SST2W
			#define W2T				SSW2T
			#define T2CA			SST2CA
			#define A2CT			SSA2CT
			#define T2CW			SST2CW
			#define W2CT			SSW2CT
			#define ocslen			sslen
			#define ocscpy			sscpy
			#define T2COLE			SST2COLE
			#define OLE2CT			SSOLE2CT
			#define T2OLE			SST2COLE
			#define OLE2T			SSOLE2CT
			#define A2OLE			SSA2OLE
			#define OLE2A			SSOLE2A
			#define W2OLE			SSW2OLE
			#define OLE2W			SSOLE2W
			#define A2COLE			SSA2COLE
			#define OLE2CA			SSOLE2CA
			#define W2COLE			SSW2COLE
			#define OLE2CW			SSOLE2CW
	
		#endif // #ifdef _MFC_VER
	#endif // #ifndef USES_CONVERSION
#endif // #ifndef SS_NO_CONVERSION

// Define ostring - generic name for std::basic_string<OLECHAR>

#if !defined(ostring) && !defined(OSTRING_DEFINED)
	typedef std::basic_string<OLECHAR> ostring;
	#define OSTRING_DEFINED
#endif

// StdCodeCvt when there's no conversion to be done
inline PSTR StdCodeCvt(PSTR pDst, int nDst, PCSTR pSrc, int nSrc)
{
	int nChars = SSMIN(nSrc, nDst);

	if ( nChars > 0 )
	{
		pDst[0]				= '\0';
		std::basic_string<char>::traits_type::copy(pDst, pSrc, nChars);
//		std::char_traits<char>::copy(pDst, pSrc, nChars);
		pDst[nChars]	= '\0';
	}

	return pDst;
}
inline PSTR StdCodeCvt(PSTR pDst, int nDst, PCUSTR pSrc, int nSrc)
{
	return StdCodeCvt(pDst, nDst, (PCSTR)pSrc, nSrc);
}
inline PUSTR StdCodeCvt(PUSTR pDst, int nDst, PCSTR pSrc, int nSrc)
{
	return (PUSTR)StdCodeCvt((PSTR)pDst, nDst, pSrc, nSrc);
}

inline PWSTR StdCodeCvt(PWSTR pDst, int nDst, PCWSTR pSrc, int nSrc)
{
	int nChars = SSMIN(nSrc, nDst);

	if ( nChars > 0 )
	{
		pDst[0]				= '\0';
		std::basic_string<wchar_t>::traits_type::copy(pDst, pSrc, nChars);
//		std::char_traits<wchar_t>::copy(pDst, pSrc, nChars);
		pDst[nChars]	= '\0';
	}

	return pDst;
}


// Define tstring -- generic name for std::basic_string<TCHAR>

#if !defined(tstring) && !defined(TSTRING_DEFINED)
	typedef std::basic_string<TCHAR> tstring;
	#define TSTRING_DEFINED
#endif

// a very shorthand way of applying the fix for KB problem Q172398
// (basic_string assignment bug)

#if defined ( _MSC_VER ) && ( _MSC_VER < 1200 )
	#define Q172398(x) (x).erase()
#else
	#define Q172398(x)
#endif

// =============================================================================
// INLINE FUNCTIONS ON WHICH CSTDSTRING RELIES
//
// Usually for generic text mapping, we rely on preprocessor macro definitions
// to map to string functions.  However the CStdStr<> template cannot use
// macro-based generic text mappings because its character types do not get
// resolved until template processing which comes AFTER macro processing.  In
// other words, UNICODE is of little help to us in the CStdStr template
//
// Therefore, to keep the CStdStr declaration simple, we have these inline
// functions.  The template calls them often.  Since they are inline (and NOT
// exported when this is built as a DLL), they will probably be resolved away
// to nothing. 
//
// Without these functions, the CStdStr<> template would probably have to broken
// out into two, almost identical classes.  Either that or it would be a huge,
// convoluted mess, with tons of "if" statements all over the place checking the
// size of template parameter CT.
// 
// In several cases, you will see two versions of each function.  One version is
// the more portable, standard way of doing things, while the other is the
// non-standard, but often significantly faster Visual C++ way.
// =============================================================================

// If they defined SS_NO_REFCOUNT, then we must convert all assignments

#ifdef SS_NO_REFCOUNT
	#define SSREF(x) (x).c_str()
#else
	#define SSREF(x) (x)
#endif

// -----------------------------------------------------------------------------