[U-Boot] [PATCH RFC] env: add command to set individual variables to default

[Wolfgang Denk]

Dear Gerlando Falauto,

In message <1315471768-21608-1-git-send-email-gerlando.falauto at keymile.com> you wrote:
> Here I am proposing an implementation for setting individual variables
> to their default values as outlined in
> http://www.denx.de/wiki/U-Boot/TaskSetEnvironmentDefaults
> 
> For instance, to reset defautl values for variables bootcmd and bootdelay:
> => env default bootcmd bootdelay
> 
> There are a few issues which are not fully covered.
> [In braces I put the behavior of this patch].
> 
> 1) Previous implementation of “env default” only worked for the whole
> environment, and “-f” was necessary in order to prevent the unexperienced
> user from messing up the environment by just typing command names.
> Should this behavior be kept? [Yes]
> 
> 2) When a variable is not defined in the default environment, should
> it get deleted (if existing)? [Yes] Should a warning be issued? [No]
> What if it is neither defined in the current nor in the default env?
> 
> 3) Should it be possible to disable this feature (i.e. to save space)?
> [No]
> Any suggestions for a meaningful configuration token?
> I was thinking of CONFIG_RESTORE_INDIVIDUAL_ENV_VARS.
> 
> 4) This implementation comes mostly from himport_r().
> It crossed my mind that it might also be useful to *import*
> individual variables from a file (rather that the default env).
> 
> For instance:
> env import [flags] addr size vars...
> 
> Would only import variables "vars" and ignore all others.
> 
> With this idea in mind I kept all himport_r()'s support for external files
> (i.e., comments, separator other than '\0', quoting).
> If no one else envisions any use for such import commands, the code could
> obviously be much smaller and simpler.
> 
> Signed-off-by: Gerlando Falauto <gerlando.falauto at keymile.com>
> Signed-off-by: Holger Brunck <holger.brunck at keymile.com>
> cc: Wolfgang Denk <wd at denx.de>
> ---
>  common/cmd_nvedit.c   |   12 +++++-
>  common/env_common.c   |  106 +++++++++++++++++++++++++++++++++++++++++++++++++
>  include/environment.h |    3 +
>  3 files changed, 119 insertions(+), 2 deletions(-)

Checkpatch says:

total: 5 errors, 0 warnings, 147 lines checked

Please clean up and resubmit.  Thanks.

Best regards,

Wolfgang Denk

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Indeed 0 lets you talk to God (setuid).
Verily is 0 all things to all people.