Idea: elimination of the normal mode

[Bean]

Hi,

First of all, one of the annoying thing about normal mode is that we
have two sets of command, one for rescue mode, one for normal mode.
Take a closer look at them, they're very similar, expect for the
argument options. If we move the option analyzer from normal.mod to
kernel, then we can have one unified set of commands.

About the duplicated commands, we can create a module minicmd to
include the most basic command, and allow for overwrite. So, there is
a minimal ls command in minicmd which would be embedded in the kernel,
but if we need the extra feature, we can load the external ls module.

After resolving the problem of two command sets, I start to wonder if
normal mode is necessary at all. In fact, its function can be
separated into the following parts:

Interface:
We can support multiple interface. The kernel's interface is a console
mode tty interface. Normal mode is the menu interface. But this is not
the only option. For example, we can have a simple chooser. The
different boot option is output line by line, and we can enter the
number to choose them. This interface is very useful in terminal that
doesn't support absulote cursor or graphic character. We can also have
graphic interface, where the layout is completely decided by the
module, not limited by interface of text mode.

Script engine:
We can also support multiple script engines. In kernel, there is just
the basic line scanner. The current normal mode engine is bash-like
parser. We can add other engines in the future, csh-like or so.

Each engine would have a separate configuration file. The default is a
line by line command list used by the kernel scanner. This look some
like preset menu of grub legacy. From this file, we load modules that
would bring us to normal environment. For example, it may look
something like this:

set rdir=/boot/grub
search -s ${rdir}/grub.cfg
insmod bash
insmod text-menu

This file would be embedded in the kernel, as root is yet to be
defined. From this file, we set the root environment and load extra
module. This would eliminate the need for static grub_prefix.

-- 
Bean