Re: [BUGS] Turkish locale bug

Tom Lane wrote:
> 
> Sezai YILMAZ <sezaiy@ata.cs.hun.edu.tr> writes:
> > With Turkish locale it is not possible to write SQL queries in
> > CAPITAL letters. SQL identifiers like "INSERT" and "UNION" first
> > are downgraded to "ınsert" and "unıon". Then "ınsert" and "unıon"
> > does not match as SQL identifier.
> 
> Ugh.
> 
> >                     for(i = 0; yytext[i]; i++)
> >                           if (isascii((unsigned char)yytext[i]) &&
> >                                 isupper(yytext[i]))
> >                                 yytext[i] = tolower(yytext[i]);
> 
> > I think it should be better to use another thing which does what
> > function tolower() does but only in English language. This should
> > stay in English locale. I think this will solve the problem.
> 
> > yytext[i] += 32;
> 
> Hm.  Several problems here:
> 
> (1) This solution would break in other locales where isupper() may
> return TRUE for characters other than 'A'..'Z'.
> 
> (2) We could fix that by gutting the isascii/isupper test as well,
> reducing it to "yytext[i] >= 'A' && yytext[i] <= 'Z'", but I'd prefer to
> still be able to say that "identifiers fold to lower case" works for
> whatever the local locale thinks is upper and lower case.  It would be
> strange if identifier folding did not agree with the SQL lower()
> function.
> 
> (3) I do not like the idea of hard-wiring knowledge of ASCII encoding
> here, even if it's unlikely that anyone would ever try to run Postgres
> on a non-ASCII-based system.
> 
> I see your problem, but I'm not sure of a solution that doesn't have bad
> side-effects elsewhere.  Ideas anyone?
> 
>                         regards, tom lane

You are right. What about this one?

================================================================
{identifier}    {                   int i;                   ScanKeyword             *keyword;
                  /* I think many platforms understands the                      following and sets locale to 7-bit
ASCII                     character set (English) */
 
        setlocale(LC_ALL, "C");  
                   for(i = 0; yytext[i]; i++)                         if (isascii((unsigned char)yytext[i]) &&
                    isupper(yytext[i]))                               yytext[i] = tolower(yytext[i]);
 
                   /* This sets locale to default locale which                       user prefer to use */
        setlocale(LC_ALL, "");  
================================================================

This works on my Linux box. But, I am not sure with other 
platforms. What do you think about performance?

regards
-sezai