Re: [Bug-tar] Enhancement: brotli integration into tar

[Sergey Poznyakoff]

Hi Marius,

Thanks for the patch.

There are two issues that strike the eye at the first glance.
First of all, the -y option is in fact reserved (see comment
in tar.c:373.

Second one is more serious:

>  static enum compress_type archive_compression_type = ct_none;
> @@ -299,6 +300,9 @@
>    { ct_lzma,     6, "\xFFLZMA" },
>    { ct_lzop,     4, "\211LZO" },
>    { ct_xz,       6, "\xFD" "7zXZ" },
> +  { ct_brotli,   4, "\x91\x19\x62\x66" }, /* suggested by Joe Tsai */
> +  { ct_brotli,   4, "\xCE\xB2\xCF\x81" }, /* suggested by Mark Adler */
> +  { ct_brotli,   0, 0 }                   /* unframed stream */
>  };

The last line means that compression recognition code will qualify any
file not matching any of the previous entries as brotli archive. I don't
think it is correct.

Regards,
Sergey