Re: [PATCH] Cygwin: pty: Add workaround for ISO-2022 and ISCII in convert_mb_str().

[Corinna Vinschen <corinna-cygwin@cygwin.com>]

On Sep 11 19:54, Takashi Yano via Cygwin-patches wrote:
> - In convert_mb_str(), exclude ISO-2022 and ISCII from the processing
>   for the case that the multibyte char is splitted in the middle.
>   The reason is as follows.
>   * ISO-2022 is too complicated to handle correctly.
>   * Not sure what to do with ISCII.
> ---
>  winsup/cygwin/fhandler_tty.cc | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/winsup/cygwin/fhandler_tty.cc b/winsup/cygwin/fhandler_tty.cc
> index 37d033bbe..ee5c6a90a 100644
> --- a/winsup/cygwin/fhandler_tty.cc
> +++ b/winsup/cygwin/fhandler_tty.cc
> @@ -117,6 +117,9 @@ CreateProcessW_Hooked
>    return CreateProcessW_Orig (n, c, pa, ta, inh, f, e, d, si, pi);
>  }
>  
> +#define IS_ISO_2022(x) ( (x) >= 50220 && (x) <= 50229 )
> +#define IS_ISCII(x) ( (x) >= 57002 && (x) <= 57011 )
> +
>  static void
>  convert_mb_str (UINT cp_to, char *ptr_to, size_t *len_to,
>  		UINT cp_from, const char *ptr_from, size_t len_from,
> @@ -126,8 +129,10 @@ convert_mb_str (UINT cp_to, char *ptr_to, size_t *len_to,
>    tmp_pathbuf tp;
>    wchar_t *wbuf = tp.w_get ();
>    int wlen = 0;
> -  if (cp_from == CP_UTF7)
> -    /* MB_ERR_INVALID_CHARS does not work properly for UTF-7.
> +  if (cp_from == CP_UTF7 || IS_ISO_2022 (cp_from) || IS_ISCII (cp_from))
> +    /* - MB_ERR_INVALID_CHARS does not work properly for UTF-7.
> +       - ISO-2022 is too complicated to handle correctly.
> +       - FIXME: Not sure what to do for ISCII.
>         Therefore, just convert string without checking */
>      wlen = MultiByteToWideChar (cp_from, 0, ptr_from, len_from,
>  				wbuf, NT_MAX_PATH);
> -- 
> 2.28.0

I'd prefer to not handle them at all.  We just don't support these
charsets, same as JIS, EBCDIC, you name it, which are not ASCII
compatible.  Let's please just drop any handling for these weird
or outdated codepages.


Thanks,
Corinna