Re: POSIX bind_textdomain_codeset(): some invalid codeset arguments

[Harald van Dijk]

On 12/05/2022 18:19, Steffen Nurpmeso via austin-group-l at The Open 
Group wrote:
> Bruno Haible wrote in
>   <4298913.vrqWZg68TM@omega>:
>   |Steffen Nurpmeso wrote:
>   |>  ...
>   |>| [.] "UTF-7"."
>   |>
>   |> That is overshoot.
>   |
>   |No. UTF-7 is invalid here because it produces output that is not NUL
>   |terminated. See:
>   |
>   |$ printf 'ab\0' | iconv -t UTF-7 | od -t c
>   |0000000   a   b   +   A   A   A   -
>   |0000007
>   |
>   |strlen() on such a return value makes invalid memory accesses.
>   |You can convince yourself by running
>   |$ OUTPUT_CHARSET=UTF-7 valgrind ls --help
>
> This is then surely bogus?  UTF-7 is a normal single byte
> character set and is to be terminated like anything else.  Nothing
> in RFC 2152 nor RFC 3501 if you want makes me think something
> else.

RFC 2152's rules 1 and 3 only allow specifying the listed characters as 
their ASCII form. All other characters, including U+0000, must be 
encoded using rule 2. GNU iconv is doing what the RFC specifies here.

Cheers,
Harald van Dijk