Re: [PATCH v2 11/15] gen_init_cpio: add newcx format

From: Taras Kondratiuk
Date: Fri Jan 26 2018 - 15:37:28 EST


Quoting Rob Landley (2018-01-25 18:40:25)
> On 01/24/2018 09:27 PM, Taras Kondratiuk wrote:
> > diff --git a/usr/gen_init_cpio.c b/usr/gen_init_cpio.c
> > index 7a2a6d85345d..78a47a5bdcb1 100644
> > --- a/usr/gen_init_cpio.c
> > +++ b/usr/gen_init_cpio.c
> > @@ -10,6 +10,7 @@
> > #include <errno.h>
> > #include <ctype.h>
> > #include <limits.h>
> > +#include <assert.h>
>
> You're adding an assert? Really?
>
> > fputs(s, stdout);
> > - offset += 110;
> > + assert((offset & 3) == 0);
> > + offset += cpio_hdr_size;
>
> Why?

Current code assumes that previous file entry in cpio is padded to 4
byte boundary. The assert just captures this assumption. It should be
true unless there is a bug in the code and some padding is missing.

Actually this assert should be a part of the next patch (#12) that
modifies padding code.