busybox: needs linux-pam dependency added if using custom busybox .config & busybox login applet

PATCH New Stefan Fröberg 3 participants 10 messages Nov 18, 2012

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Stefan Fröberg

author

2012-11-18 00:15 UTC #0 lore raw

PATCH 1/1 busybox: needs linux-pam dependency added if using custom busybox .config & busybox login applet

If BusyBox custom .config has login applet (CONFIG_LOGIN) enabled then the build process will complain about missing Linux PAM headers.
This will add the needed linux-pam dependency

Signed-off-by Stefan Fr?berg <[email protected]>

---
 package/busybox/busybox.mk |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

package/busybox/busybox.mk +7 -0

index 549e150..f2a102a 100644
@@ -30,6 +30,13 @@ BUSYBOX_CFLAGS += -I$(STAGING_DIR)/usr/include/tirpc/
 BUSYBOX_LDFLAGS += -ltirpc
 endif
 
+# linux-pam must be built first if user has custom
+# BusyBox .config file and that file has also login
+# applet (CONFIG_LOGIN) enabled.
+ifeq ($(shell sed -n "s/CONFIG_LOGIN=\(y\)/\1/p" $(BR2_PACKAGE_BUSYBOX_CONFIG)),y)
+BUSYBOX_DEPENDENCIES += linux-pam
+endif
+
 BUSYBOX_BUILD_CONFIG = $(BUSYBOX_DIR)/.config
 # Allows the build system to tweak CFLAGS
 BUSYBOX_MAKE_ENV = $(TARGET_MAKE_ENV) CFLAGS="$(BUSYBOX_CFLAGS)"

Signature · 1 line

1.7.7.6

Danomi Manchego

2012-11-18 02:14 UTC #1 lore raw

PATCH 1/1 busybox: needs linux-pam dependency added if using custom busybox .config & busybox login applet

package/busybox/busybox.mk BUSYBOX_CFLAGS += -I$(STAGING_DIR)/usr/include/tirpc/ · line 38

Quoted 6 lines · Stefan Fr?berg

+ifeq ($(shell sed -n "s/CONFIG_LOGIN=$y$/\1/p"
$(BR2_PACKAGE_BUSYBOX_CONFIG)),y)
package/busybox/busybox.mk +2 -0
+BUSYBOX_DEPENDENCIES += linux-pam
+endif

Why bother with the sed? Could you not do "ifeq
($(BR2_PACKAGE_LINUX_PAM),y)"?

Just a thought ...
Danomi -
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Stefan Fröberg

author

2012-11-18 11:51 UTC #2 lore raw

PATCH 1/1 busybox: needs linux-pam dependency added if using custom busybox .config & busybox login applet

Hi Danomi
18.11.2012 4:14, Danomi Manchego kirjoitti:

Quoted 7 lines

On Sat, Nov 17, 2012 at 7:15 PM, Stefan Fr?berg
<[email protected]
<mailto:[email protected]>> wrote:

Quoted 9 lines

    +ifeq ($(shell sed -n "s/CONFIG_LOGIN=$y$/\1/p"
    $(BR2_PACKAGE_BUSYBOX_CONFIG)),y)
    +BUSYBOX_DEPENDENCIES += linux-pam
    +endif
Why bother with the sed? Could you not do "ifeq
($(BR2_PACKAGE_LINUX_PAM),y)"?

No because I don't have a need for full linux-pam login binary.

I only need linux-pam because I have login applet enabled inside my custom BusyBox .config file
and that needs Linux Pam headers.

Regards
Stefan

Quoted 3 lines

Just a thought ...
Danomi -

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Stefan Fröberg

author

2012-11-18 12:11 UTC #3 lore raw

PATCH 1/1 busybox: needs linux-pam dependency added if using custom busybox .config & busybox login applet

18.11.2012 13:51, Stefan Fr?berg kirjoitti:

Quoted 15 lines

Hi Danomi
18.11.2012 4:14, Danomi Manchego kirjoitti:
Quoted 13 lines
On Sat, Nov 17, 2012 at 7:15 PM, Stefan Fr?berg
<[email protected]
<mailto:[email protected]>> wrote:
    +ifeq ($(shell sed -n "s/CONFIG_LOGIN=$y$/\1/p"
    $(BR2_PACKAGE_BUSYBOX_CONFIG)),y)
    +BUSYBOX_DEPENDENCIES += linux-pam
    +endif

Quoted 9 lines

Quoted 3 lines
Why bother with the sed? Could you not do "ifeq
($(BR2_PACKAGE_LINUX_PAM),y)"?
No because I don't have a need for full linux-pam login binary.
I only need linux-pam because I have login applet enabled inside my custom BusyBox .config file
and that needs Linux Pam headers.

Or to but it in another way:

BR2_PACKAGE_LINUX_PAM is not enough. BusyBox .config must also have CONFIG_LOGIN enabled.
And that needs to be determined before the whole .mk is parsed, at a runtime, so that proper
dependency can be added.

In normal default buildroot provided BusyBox .config there is no CONFIG_LOGIN enabled in.
So for that case this will change nothing.

It seems that the stuff inside .mk files are really static (and so called functions are not functions at all
but just variables containing text).

So I had to go outside of .mk file for a moment and determine if CONFIG_LOGIN was enabled outside of extracted
busybox dir and then add the needed dependency.

I know this is ugly but Im open to suggestions.

Regards
Stefan

Quoted 10 lines

Regards
Stefan
Quoted 3 lines
Just a thought ...
Danomi -

Quoted 4 lines

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buildroot mailing list
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http://lists.busybox.net/mailman/listinfo/buildroot

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Stefan Fröberg

author

2012-11-18 14:01 UTC #4 lore raw

PATCH 1/1 busybox: needs linux-pam dependency added if using custom busybox .config & busybox login applet

18.11.2012 14:11, Stefan Fr?berg kirjoitti:

Quoted 41 lines

18.11.2012 13:51, Stefan Fr?berg kirjoitti:
Quoted 15 lines
Hi Danomi
18.11.2012 4:14, Danomi Manchego kirjoitti:
Quoted 13 lines
On Sat, Nov 17, 2012 at 7:15 PM, Stefan Fr?berg
<[email protected]
<mailto:[email protected]>> wrote:
    +ifeq ($(shell sed -n "s/CONFIG_LOGIN=$y$/\1/p"
    $(BR2_PACKAGE_BUSYBOX_CONFIG)),y)
    +BUSYBOX_DEPENDENCIES += linux-pam
    +endif
Quoted 9 lines
Quoted 3 lines
Why bother with the sed? Could you not do "ifeq
($(BR2_PACKAGE_LINUX_PAM),y)"?
No because I don't have a need for full linux-pam login binary.
I only need linux-pam because I have login applet enabled inside my custom BusyBox .config file
and that needs Linux Pam headers.
Or to but it in another way:
BR2_PACKAGE_LINUX_PAM is not enough. BusyBox .config must also have CONFIG_LOGIN enabled.
And that needs to be determined before the whole .mk is parsed, at a runtime, so that proper
dependency can be added.
In normal default buildroot provided BusyBox .config there is no CONFIG_LOGIN enabled in.
So for that case this will change nothing.
It seems that the stuff inside .mk files are really static (and so called functions are not functions at all
but just variables containing text).

Quoted 9 lines

So I had to go outside of .mk file for a moment and determine if CONFIG_LOGIN was enabled outside of extracted
busybox dir and then add the needed dependency.
I know this is ugly but Im open to suggestions.
Regards
Stefan

Actually, maybe that should be changed to host-linux-pam ... Because AFAIK, BusyBox login applet needs only headers and nothing more ???

Quoted 20 lines

Quoted 13 lines
Regards
Stefan
Quoted 3 lines
Just a thought ...
Danomi -
Quoted 4 lines
_______________________________________________
buildroot mailing list
buildroot at busybox.net
http://lists.busybox.net/mailman/listinfo/buildroot

Quoted 4 lines

_______________________________________________
buildroot mailing list
buildroot at busybox.net
http://lists.busybox.net/mailman/listinfo/buildroot

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Thomas Petazzoni

2012-11-18 16:40 UTC #5 lore raw

PATCH 1/1 busybox: needs linux-pam dependency added if using custom busybox .config & busybox login applet

In reply to Stefan Fröberg

Dear Stefan Fr?berg,

package/busybox/busybox.mk BUSYBOX_CFLAGS += -I$(STAGING_DIR)/usr/include/tirpc/ · line 38

Quoted 6 lines · Stefan Fr?berg

package/busybox/busybox.mk +6 -0

+# linux-pam must be built first if user has custom
+# BusyBox .config file and that file has also login
+# applet (CONFIG_LOGIN) enabled.
+ifeq ($(shell sed -n "s/CONFIG_LOGIN=\(y\)/\1/p" $(BR2_PACKAGE_BUSYBOX_CONFIG)),y)
+BUSYBOX_DEPENDENCIES += linux-pam
+endif

I don't think this will work nicely. BR2_PACKAGE_BUSYBOX_CONFIG is the source for the Busybox configuration, but the user can do "make busybox-menuconfig" do adjust it. In this case, the contents of the BR2_PACKAGE_BUSYBOX_CONFIG file and the contents of the real configuration file used by Busybox are different. If the latter has CONFIG_LOGIN, but not the former, then you will not link against linux-pam while you should.

It is really difficult to have dependencies that are needed only when some specific Busybox features are enabled.

Best regards,

Thomas

Signature · 4 lines

Thomas Petazzoni, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com

Stefan Fröberg

author

2012-11-18 17:39 UTC #6 lore raw

PATCH 1/1 busybox: needs linux-pam dependency added if using custom busybox .config & busybox login applet

Hi Thomas

18.11.2012 18:40, Thomas Petazzoni kirjoitti:

Quoted 4 lines

Dear Stefan Fr?berg,
On Sun, 18 Nov 2012 02:15:13 +0200, Stefan Fr?berg wrote:

Quoted 13 lines

package/busybox/busybox.mk BUSYBOX_CFLAGS += -I$(STAGING_DIR)/usr/include/tirpc/ · line 38
Quoted 6 lines
package/busybox/busybox.mk +6 -0
+# linux-pam must be built first if user has custom
+# BusyBox .config file and that file has also login
+# applet (CONFIG_LOGIN) enabled.
+ifeq ($(shell sed -n "s/CONFIG_LOGIN=$y$/\1/p" $(BR2_PACKAGE_BUSYBOX_CONFIG)),y)
+BUSYBOX_DEPENDENCIES += linux-pam
+endif
I don't think this will work nicely. BR2_PACKAGE_BUSYBOX_CONFIG is the source for the Busybox configuration, but the user can do "make busybox-menuconfig" do adjust it. In this case, the contents of the BR2_PACKAGE_BUSYBOX_CONFIG file and the contents of the real configuration file used by Busybox are different. If the latter has CONFIG_LOGIN, but not the former, then you will not link against linux-pam while you should.

I tested this and it seems that no matter what you do in make busybox-menuconfig the
(enable login or disable login) the settings from BR2_PACKAGE_BUSYBOX_CONFIG will
always override.
So even if setting CONFIG_LOGIN disabled from make busybox-menuconfig it will still
build linux-pam first.

I try to get the logic of this thing:

First busybox is extracted and it copies $(BUSYBOX_CONFIG_FILE) (really a BR2_PACKAGE_BUSYBOX_CONFIG)
over to just extracted output/busybox-xyz/.config and replacing it. That will be done in BUSYBOX_POST_EXTRACT_HOOKS.

(BR2_PACKAGE_BUSYBOX_CONFIG here being either the default package/busybox/busybox-xyz.x.config
or user provided custom .config)

Then buildroot makes some of it's own changes to that output/busybox/.config inside BUSYBOX_CONFIGURE_CMDS

Then build.

So what make busybox-menuconfig actually does is change
output/busybox-xyz/.config.

So instead of getting CONFIG_LOG setting from BR2_PACKAGE_BUSYBOX_CONFIG (aka BUSYBOX_CONFIG_FILE inside busybox.mk)
I should get it from output/busybox-xyz/.config (aka BUSYBOX_BUILD_CONFIG inside busybox.mk).

And that CONFIG_LOGIN checking should be done after buybox tarball has been extracted but by then, it is already too late for determining dependencies ....
Aarrggggh!

Quoted 2 lines

It is really difficult to have dependencies that are needed only when some specific Busybox features are enabled.

Tell me about it.
What IMHO is needed, is some function or way to get these kinds of information.
Just before dependencies are determined.

There should be KCONFIG_GET_OPT or something similar inside package/pkg-utils.mk
(like there already is KCONFIG_ENABLE_OPT, KCONFIG_DISABLE_OPT and KCONFIG_SET_OPT)
that would help to determine not only buildroot features but also linux features and any
else package that use kconfig like stuff.

It would also help in case of various package conflicts (say if busybox unzip applet and real unzip are mistakenly
being installed, then this could be detected beforehand)

Regards
Stefan

Quoted 3 lines

Best regards,
Thomas

Thomas Petazzoni

2012-11-18 17:48 UTC #7 lore raw

PATCH 1/1 busybox: needs linux-pam dependency added if using custom busybox .config & busybox login applet

Dear Stefan Fr?berg,

Quoted 4 lines · Stefan Fr?berg

And that CONFIG_LOGIN checking should be done after buybox tarball has been extracted but by then, it is already too late for determining dependencies ....
Aarrggggh!

I think you understood what the problem is :)

Quoted 15 lines

Quoted 2 lines
It is really difficult to have dependencies that are needed only when some specific Busybox features are enabled.
Tell me about it.
What IMHO is needed, is some function or way to get these kinds of information.
Just before dependencies are determined.
There should be KCONFIG_GET_OPT or something similar inside package/pkg-utils.mk
(like there already is KCONFIG_ENABLE_OPT, KCONFIG_DISABLE_OPT and KCONFIG_SET_OPT)
that would help to determine not only buildroot features but also linux features and any
else package that use kconfig like stuff.

Quoted 3 lines

It would also help in case of various package conflicts (say if busybox unzip applet and real unzip are mistakenly
being installed, then this could be detected beforehand)

KCONFIG_GET_OPT cannot work: you could only call it in a Makefile rule (i.e inside BUILD_CMDS or CONFIGURE_CMDS or a hook or something like that). But by the time those are executed, it is way too late to declare a dependency. The dependencies (in BUSYBOX_DEPENDENCIES) must be detailed when make parses all the .mk files, not when the rules are executed.

Unless I'm wrong, linux-pam is only needed if ENABLE_PAM is defined when building Busybox, correct? So, CONFIG_LOGIN builds just fine without PAM, doesn't it?

So maybe you should rather do:

ifeq ($(BR2_PACKAGE_LINUX_PAM),y)
BUSYBOX_DEPENDENCIES += linux-pam
BUSYBOX_CFLAGS += -DENABLE_PAM
endif

No?

Thomas

Signature · 4 lines

Thomas Petazzoni, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com

Stefan Fröberg

author

2012-11-18 18:09 UTC #8 lore raw

PATCH 1/1 busybox: needs linux-pam dependency added if using custom busybox .config & busybox login applet

18.11.2012 19:48, Thomas Petazzoni kirjoitti:

Quoted 35 lines

Dear Stefan Fr?berg,
Quoted 4 lines · Stefan Fr?berg
And that CONFIG_LOGIN checking should be done after buybox tarball has been extracted but by then, it is already too late for determining dependencies ....
Aarrggggh!
I think you understood what the problem is :)
Quoted 15 lines
Quoted 2 lines
It is really difficult to have dependencies that are needed only when some specific Busybox features are enabled.
Tell me about it.
What IMHO is needed, is some function or way to get these kinds of information.
Just before dependencies are determined.
There should be KCONFIG_GET_OPT or something similar inside package/pkg-utils.mk
(like there already is KCONFIG_ENABLE_OPT, KCONFIG_DISABLE_OPT and KCONFIG_SET_OPT)
that would help to determine not only buildroot features but also linux features and any
else package that use kconfig like stuff.
Quoted 3 lines
It would also help in case of various package conflicts (say if busybox unzip applet and real unzip are mistakenly
being installed, then this could be detected beforehand)
KCONFIG_GET_OPT cannot work: you could only call it in a Makefile rule (i.e inside BUILD_CMDS or CONFIGURE_CMDS or a hook or something like that). But by the time those are executed, it is way too late to declare a dependency. The dependencies (in BUSYBOX_DEPENDENCIES) must be detailed when make parses all the .mk files, not when the rules are executed.

Quoted 3 lines

Unless I'm wrong, linux-pam is only needed if ENABLE_PAM is defined when building Busybox, correct? So, CONFIG_LOGIN builds just fine without PAM, doesn't it?

Yes that is correct, there is a CONFIG_PAM in BusyBox .config and althought I have never actually tried to build it without pam it should in theory work.

Quoted 9 lines

So maybe you should rather do:
ifeq ($(BR2_PACKAGE_LINUX_PAM),y)
BUSYBOX_DEPENDENCIES += linux-pam
BUSYBOX_CFLAGS += -DENABLE_PAM
endif
No?

Hmmm...
I will try that and see.

Thanks!

Regards
Stefan

Quoted 1 line

Thomas

Thomas Petazzoni

2012-11-18 18:28 UTC #9 lore raw

PATCH 1/1 busybox: needs linux-pam dependency added if using custom busybox .config & busybox login applet

Dear Stefan Fr?berg,

Quoted 4 lines · Stefan Fr?berg

Quoted 4 lines
ifeq ($(BR2_PACKAGE_LINUX_PAM),y)
BUSYBOX_DEPENDENCIES += linux-pam
BUSYBOX_CFLAGS += -DENABLE_PAM
endif

Hum, wait, I didn't see there was a CONFIG_PAM option. So what you want to do is:

ifeq ($(BR2_PACKAGE_LINUX_PAM),y)
BUSYBOX_DEPENDENCIES += linux-pam
endif

And then, in the Busybox configuration step, do:

ifeq ($(BR2_PACKAGE_LINUX_PAM),y)

	$(call KCONFIG_SET_OPT,CONFIG_PAM,/path/to/busybox/config/file)

endif

or something along those lines.

Thomas

Signature · 4 lines

Thomas Petazzoni, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com