On Mon, 20 Apr 2009, Eugen Dedu wrote: > I see now the corresponding function, at > http://lxr.linux.no/linux+v2.6.29/drivers/usb/core/message.c#L761. I > looked at several places where it is used, and until now it seems that > changing it to utf-8 has no negative impacts on the other code. Do you > think that it is feasible (easy) to really make this change? It is feasible, but there are a couple of things to watch out for: With latin-1 encoding we know that each character occupies only one byte; therefore any descriptor string will fit into a 128-byte buffer (since the total descriptor length can't be larger than 255). But with UTF-8 encoding, a character can occupy more than one byte. Hence the callers may need to allocate larger buffers than they do now. For instance, you would definitely want to change usb_cache_string(). Translation from UTF-16LE to latin-1 is easy. Translation to UTF-8 is harder because it requires you to check for invalid code points. Furthermore, if you write your own code to do the translation then you are almost certainly duplicating code that already exists somewhere else in the kernel, which is a bad idea. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
