[PATCH v2 0/2] env: setenv add resolve value option

[Art Nikpal]

hi Wolfgang
tnx for your comments

On Fri, Nov 19, 2021 at 3:49 PM Wolfgang Denk <wd at denx.de> wrote:
>
> Dear Artem,
>
> In message <20211119043647.1251416-1-art at khadas.com> you wrote:
> > Add possibility setup env variable with additional resolving vars inside
> > value.
>
> Hm... if you want to evaluate variables, you should not prevent the
> shell to do that by enclosing them in apostrophes?
>

next examples just demonstrate how its works for already defined env
variables which contain other variables (like storred env variables)

> > Usage examples:
> >
> > => setenv a hello; setenv b world; setenv c '${a} ${b}'
> > => setenv -r d '${c}! ${a}...'
> > => printenv d
> > d=hello world! hello...
>
> Without any new code added:
>

sure I know about this ! see my prev message please .

> => setenv a hello; setenv b world; setenv c ${a} ${b}
> => setenv d ${c}! ${a}...
> => printenv d
> d=hello world! hello...
>
>
> I know very well that this does not cover all use cases you might

Why not have this new opportunity ?

> have in mind, as you speak of "deep resolve". But then, I'm first
> missing an explanation (and documentation) of what "deep resolve"

recurrent  resolving for variables

> actually means in this context, i. e. how many levels down you
> evaluat.   Oh...  the code has "int max_loop = 32;" - this is a

i think its will be enough

> limitation mentioned nowhere.  And are you really sure this is a
> clever idea?  I am not convinced.  If we do something like this, we
> should not invent a new non-standard way.  We should implement

I believe it's a good idea ;-)

> standard shell behaviour instead (i. e. for example something like
> the eval command).

1) this option did not broke any exist compatibilities
2) there we talk not only about uboot shell, same time will be useful
to have env_resolve for internal c usage, because env_set dont have
this feature

>
> > Artem Lapkin (2):
> >   env: setenv add resolve value option
> >   test: env: deep resolve value testing
>
> This is one more of the patches that actually try to fix existing
> problems with our ancient verion of the hush shell.  As far as I
> understand, Francis (added to Cc:) has started working on an update
> of hush to a current version.  We should rather help him with that
> instead of implementing non-standard workarounds.

yes i'm informed  about this plans  (and think its happens  not  so
soon - but i provide some simple elegant solution already)
but again we dont have env_resolve for internal c usage which must be
very useful

for example: pxe_utils.c: and some other places
env_set("bootargs", finalbootargs);
can be replaced by env_resolve("bootargs", ..... )
will be easy get useful features via simple solution ( deep resolve
all vars by one line )

>
> Best regards,
>

Big tnx again ! and waiting any other ideas about this

> Wolfgang Denk
>
> --
> DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
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