Converting LCID to Language string

In my application I have to query for System and User Locale and return them as strings(like en-US instead of language codes). I can get the LCID for these Languages from GetSystemDefaultLCID() 开发者_StackOverflow中文版and GetUserDefaultLCID() functions, but what I am struggling with is the conversion from LCID to Language strings.

My app has to run on Windows XP as well so I can't use the LCIDToLocaleName() Win API. The only I have been able to Get the locale name so far is to use the GetLocaleInfo() Win API by passing LOCALE_SYSTEM_DEFAULT and LOCALE_USER_DEFAULT as LCID and LOCALE_SISO639LANGNAME as LCType. My code looks somewhat like this to Query for System Locale

int localeBufferSize = GetLocaleInfo(LOCALE_SYSTEM_DEFAULT, LOCALE_SISO639LANGNAME, NULL, 0);
char *sysLocale = new char[localeBufferSize];
GetLocaleInfo(LOCALE_SYSTEM_DEFAULT, LOCALE_SISO639LANGNAME, sysLocale,localeBufferSize);

But the value I get is only the language name(only en of en-US). To get the full locale I have to call GetLocaleInfo() twice passing LOCALE_SISO3166CTRYNAME as the LCType the second time and then append the two values. Is there any better way to do this?

Sorry to say that, but no. Only the two (or more) letter codes are standardized, the concatenation of them are not. But! There is no need for the dynamic buffer allocation. Quoted from MSDN:

The maximum number of characters allowed for this string is nine, including a terminating null character.

Reading this, it sounds overkill to dynamically allocate the required buffer, so if you really want to keep it extra-clean, you can do something like this:

char buf[19];
int ccBuf = GetLocaleInfo(LOCALE_SYSTEM_DEFAULT, LOCALE_SISO639LANGNAME, buf, 9);
buf[ccBuf++] = '-';
ccBuf += GetLocaleInfo(LOCALE_SYSTEM_DEFAULT, LOCALE_SISO3166CTRYNAME, buf+ccBuf, 9);