On 03/31/2014 08:51 AM, Peter Geoghegan wrote:
+ #ifdef HAVE_LOCALE_T
+       if (tss->locale)
+               strxfrm_l(pres, tss->buf1, Min(sizeof(Datum), len), 
tss->locale);
+       else
+ #endif
+               strxfrm(pres, tss->buf1, Min(sizeof(Datum), len));
+
+       pres[Min(sizeof(Datum) - 1, len)] = '\0';


I'm afraid that trick isn't 100% reliable. The man page for strxrfm says:

RETURN VALUE
       The strxfrm() function returns the number of bytes  required  to  store
       the  transformed  string  in  dest  excluding the terminating null byte
       ('\0').  If the value returned is n or more, the contents of  dest  are
       indeterminate.

Note the last sentence. To avoid the undefined behavior, you have to pass a buffer that's large enough to hold the whole result, and then truncate the result.

- Heikki


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