[Bug-xorriso] bootspec grub2_mbr broken

[Daniel Martin]

Hi,

I just wanted to test the xorriso option grub2_mbr and got:
    xorriso : FAILURE : Unrecognized keyword with -boot_image grub grub2_mbr=on
    xorriso : HINT : Allowed with grub2_mbr= are: off , on
What?

The problem seems to exists since its introduction as the code hasn't changed:
    
http://libburnia-project.org/browser/libisoburn/trunk/xorriso/opts_a_c.c#L1129

Here the string comparisions are wrong:
    strcmp(treatpt + 9, "off")
and
    strcmp(treatpt + 9, "on").

+9 is one character to short as it misses the equal sign and the
strcmps compare on/off with =on/=off.
(Just quickly) comparing it with other options the initial check:
    strncmp(treatpt, "grub2_mbr=", 9)
should've been
    strncmp(treatpt, "grub2_mbr=", 10)
and the following "+9"s might be copy errors.

I hope that I have the time to send a patch this evening.

But, when seeing this error no one should have been able to use this
option before. Is it supposed to work? ;)


Cheers,
    Daniel Martin