asciiStrup
Converts all lower case ASCII letters to upper case ASCII letters, with semantics that exactly match func@GLib.ascii_toupper.
Return
a newly-allocated string, with all the lower case characters in @str converted to upper case. (Note that this is unlike the old func@GLib.strup, which modified the string in place.)
Parameters
str
a string
len
length of @str in bytes, or -1 if @str is nul-terminated