Re: [PATCH 1/1] kconfig: Add a configuration subtree command to kconfig

konrad.gaisler
2011-11-18T22:51:05Z

On 11/18/2011 07:09 PM, Randy Dunlap wrote:
> (changed linux-config@ to linux-kbuild@vger.kernel.org)
>
> On 11/18/2011 06:16 AM, Konrad Eisele wrote:
>> New kconfig command "subsource":
>> subsource "<kconfig>""<cwd>""<.config>"" "<internal_prefix> <.config_prefix>
>> Allocates<kconfig> as a configuration subtree using<.config> as the configuration
>> file to save and load from.<cwd> is the directory path to switch to for "source" to
>> work, " " is the Menu tile of the subtree,<internal_prefix> is a internal prefix,
>> and<.config_prefix> is the prefix to append/remove when saving/loading<.config>.
> That explains what but not why. You need some justification(s) for such
> a large patch. Maybe even some example usages.
The patch originated from a buildsystem that uses buildroot and linux.
Both use Kconfig and the buildsystem itself uses Kconfig. To configure
a subproject you have to exit the toplevel Kconfig and restart to
startup a subproject Kconfig, It is even more anoying when looking
inside buildroot. It has in its turn subprojects uClibc, busybox,
linux, crosstools-ng which all use Kconfig. The subtree patch
does make it possible to unify all in one Kconfig.

As an example, apply the patch, then add to <top>/Kconfig the lines:

subsource "arch/sparc/Kconfig" "." ".config_sparc" "SPARC config" SPARC_
CONFIG_
subsource "arch/mips/Kconfig" "." ".config_mips" "MIPS config" MIPS_ CONFIG_
(my mailclient breaks up the lines, it should be 2 lines only).

Then start "make xconfig" once to build "qconfig". The patch adds an
extra option to qconfig (also mconfig, gconfig and nconfig) "-s". This
option enables the "subsource" tag. Now start qconfig:
$<path-to-qconfig>/qconfig -s Kconfig

Then you see a subtree "Sparc config" and "Mips config" that is a sparc
and mips complete Kconfig. They are independent from another. The Sparc
subtree is saved/loaded from .config_sparc, the Mips subtree is
saved/loaded from .config_mips. No namespace clash.

Note that without the "-s" option the Kconfig behaviour is as usual. I
think it would be a help for many projects that use Kconfig.

-- Konrad

>
>> Signed-off-by: Konrad Eisele<konrad@gaisler.com>
>> ---
>> scripts/kconfig/conf.c | 6 +-
>> scripts/kconfig/confdata.c | 83 ++-
>> scripts/kconfig/expr.h | 16 +
>> scripts/kconfig/gconf.c | 3 +
>> scripts/kconfig/lkc.h | 1 +
>> scripts/kconfig/lkc_proto.h | 12 +-
>> scripts/kconfig/mconf.c | 13 +-
>> scripts/kconfig/menu.c | 18 +-
>> scripts/kconfig/nconf.c | 13 +-
>> scripts/kconfig/qconf.cc | 3 +
>> scripts/kconfig/symbol.c | 50 ++-
>> scripts/kconfig/util.c | 49 ++
>> scripts/kconfig/zconf.gperf | 1 +
>> scripts/kconfig/zconf.hash.c_shipped | 252 +++++-----
>> scripts/kconfig/zconf.l | 50 ++-
>> scripts/kconfig/zconf.lex.c_shipped | 52 ++-
>> scripts/kconfig/zconf.tab.c_shipped | 985 ++++++++++++++++++----------------
>> scripts/kconfig/zconf.y | 23 +-
>> 18 files changed, 991 insertions(+), 639 deletions(-)
>
>