/*

#define DEFINE_UNICODE		FALSE

#define _PATH_SEPARATOR_CHR	'\\'

#define PATH_CCH_ADD_EXTENSION	PathCchAddExtensionA

*/

#if DEFINE_UNICODE

HRESULT PATH_CCH_ADD_EXTENSION(PWSTR pszPath, size_t cchPath, PCWSTR pszExt)

{

#ifdef _WIN32

	LPWSTR pDot;

	BOOL bExtDot;

	LPWSTR pBackslash;

	size_t pszExtLength;

	size_t pszPathLength;

	if (!pszPath)

		return E_INVALIDARG;

	if (!pszExt)

		return E_INVALIDARG;

	pszExtLength = lstrlenW(pszExt);

	pszPathLength = lstrlenW(pszPath);

	bExtDot = (pszExt[0] == '.') ? TRUE : FALSE;

	pDot = wcsrchr(pszPath, '.');

	pBackslash = wcsrchr(pszPath, _PATH_SEPARATOR_CHR);

	if (pDot && pBackslash)

	{

		if (pDot > pBackslash)

			return S_FALSE;

	}

	if (cchPath > pszPathLength + pszExtLength + ((bExtDot) ? 0 : 1))

	{

		if (bExtDot)

			swprintf_s(&pszPath[pszPathLength], cchPath - pszPathLength, L"%s", pszExt);

		else

			swprintf_s(&pszPath[pszPathLength], cchPath - pszPathLength, L".%s", pszExt);

		return S_OK;

	}

#endif

	return HRESULT_FROM_WIN32(ERROR_INSUFFICIENT_BUFFER);

}

#else

HRESULT PATH_CCH_ADD_EXTENSION(PSTR pszPath, size_t cchPath, PCSTR pszExt)

{

	CHAR* pDot;

	BOOL bExtDot;

	CHAR* pBackslash;

	size_t pszExtLength;

	size_t pszPathLength;

	if (!pszPath)

		return E_INVALIDARG;

	if (!pszExt)

		return E_INVALIDARG;

	pszExtLength = lstrlenA(pszExt);

	pszPathLength = lstrlenA(pszPath);

	bExtDot = (pszExt[0] == '.') ? TRUE : FALSE;

	pDot = strrchr(pszPath, '.');

	pBackslash = strrchr(pszPath, _PATH_SEPARATOR_CHR);

	if (pDot && pBackslash)

	{

		if (pDot > pBackslash)

			return S_FALSE;

	}

	if (cchPath > pszPathLength + pszExtLength + ((bExtDot) ? 0 : 1))

	{

		if (bExtDot)

			sprintf_s(&pszPath[pszPathLength], cchPath - pszPathLength, "%s", pszExt);

		else

			sprintf_s(&pszPath[pszPathLength], cchPath - pszPathLength, ".%s", pszExt);

		return S_OK;

	}

	return HRESULT_FROM_WIN32(ERROR_INSUFFICIENT_BUFFER);

}

#endif

/*

#undef DEFINE_UNICODE

#undef _PATH_SEPARATOR_CHR

#undef PATH_CCH_ADD_EXTENSION

*/