Re: [PATCH v2 4/5] cryptodisk: Use enum constants as indexes into cryptomount option array

[Glenn Washburn]

On Thu, 19 May 2022 20:24:11 +0200
Daniel Kiper <dkiper@net-space.pl> wrote:

> On Fri, May 13, 2022 at 12:00:50PM -0500, Glenn Washburn wrote:
> > Signed-off-by: Glenn Washburn <development@efficientek.com>
> > ---
> >  grub-core/disk/cryptodisk.c | 53 ++++++++++++++++++++++---------------
> >  1 file changed, 32 insertions(+), 21 deletions(-)
> >
> > diff --git a/grub-core/disk/cryptodisk.c b/grub-core/disk/cryptodisk.c
> > index 94640b502..ecbda7ce9 100644
> > --- a/grub-core/disk/cryptodisk.c
> > +++ b/grub-core/disk/cryptodisk.c
> > @@ -35,6 +35,17 @@ GRUB_MOD_LICENSE ("GPLv3+");
> >
> >  grub_cryptodisk_dev_t grub_cryptodisk_list;
> >
> > +enum
> > +  {
> > +    OPTION_UUID,
> > +    OPTION_ALL,
> > +    OPTION_BOOT,
> > +    OPTION_PASSWORD,
> > +    OPTION_KEYFILE,
> > +    OPTION_KEYFILE_OFFSET,
> > +    OPTION_KEYFILE_SIZE
> > +  };
> 
> I would prefer constants here.

I chose enum because that is consistent with many other commands. By
"constants" do you mean CPP defined macros? I can imagine you would
mean variables with the "const" property. Without having done an
exhaustive search, I don't believe any commands use CPP macros for the
index. Here's a list of files for commands that use enums as the index:

grub-core/commands/i386/pc/drivemap.c
grub-core/commands/file.c
grub-core/commands/pgp.c
grub-core/commands/search_wrap.c
grub-core/term/gfxterm_background.c
grub-core/term/serial.c
grub-core/term/terminfo.c

The benefits of enum over CPP macro is that inserting into the enum
list automatically renumbers the subsequent constants in the list. I
failing to think of a good way to do that with CPP macros. Could you
explain a little further precisely what you're wanting (maybe I've
guessed wrong) and why you see it as superior to using enums?

Glenn

> 
> Otherwise patches LGTM.
> 
> Daniel