msdos_format_name() bug?

msdos_format_name() bug?

[Roel Kluin]

in msdos_format_name(const unsigned char *name, int len, ...)

name is the proposed name, len is its length.

        while (c != '.' && len--)
                c = *name++;
        if (c == '.') {
                while (walk - res < 8)
                        *walk++ = ' ';
                while (len > 0 && walk - res < MSDOS_NAME) {

Is the postfix decrement in the first loop correct, or should it be
prefix? (isn't that one character too many?)

If not, note that if the proposed name ends with a dot: e.g.
'myfile.' the first while loop iterates until the dot which ends
the loop, but because of the postfix decrement len already is 0,
so the third while loop won't start. Is that correct?

Roel

Re: msdos_format_name() bug?

[OGAWA Hirofumi]

Roel Kluin <roel.kluin@gmail.com> writes:

> in msdos_format_name(const unsigned char *name, int len, ...)
>
> name is the proposed name, len is its length.
>
>         while (c != '.' && len--)
>                 c = *name++;
>         if (c == '.') {
>                 while (walk - res < 8)
>                         *walk++ = ' ';
>                 while (len > 0 && walk - res < MSDOS_NAME) {
>
> Is the postfix decrement in the first loop correct, or should it be
> prefix? (isn't that one character too many?)
>
> If not, note that if the proposed name ends with a dot: e.g.
> 'myfile.' the first while loop iterates until the dot which ends
> the loop, but because of the postfix decrement len already is 0,
> so the third while loop won't start. Is that correct?

In the "myfile." case, it seems correct. It will provide "MYFILE     ".
-- 
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>