[Buildroot] [PATCH] build: fix umask test

[Buildroot] [PATCH] build: fix umask test

[Kurt Van Dijck]

Some shells' builtin umask does not print 2 leading 0's for the umask.
Not doing so would break the comparison.
This patch makes sure that the umask has (at least) 4 digits.

Signed-off-by: Kurt Van Dijck <dev.kurt@vandijck-laurijssen.be>
---
 Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index 63502d0..9a36769 100644
--- a/Makefile
+++ b/Makefile
@@ -26,7 +26,7 @@
 
 # Trick for always running with a fixed umask
 UMASK = 0022
-ifneq ($(shell umask),$(UMASK))
+ifneq ($(shell printf "%04o\n" `umask`),$(UMASK))
 .PHONY: _all $(MAKECMDGOALS)
 
 $(MAKECMDGOALS): _all

[Buildroot] [PATCH] build: fix umask test

[Peter Korsgaard]

>>>>> "Kurt" == Kurt Van Dijck <dev.kurt@vandijck-laurijssen.be> writes:

 > Some shells' builtin umask does not print 2 leading 0's for the umask.
 > Not doing so would break the comparison.
 > This patch makes sure that the umask has (at least) 4 digits.

 > Signed-off-by: Kurt Van Dijck <dev.kurt@vandijck-laurijssen.be>
 > ---
 >  Makefile | 2 +-
 >  1 file changed, 1 insertion(+), 1 deletion(-)

 > diff --git a/Makefile b/Makefile
 > index 63502d0..9a36769 100644
 > --- a/Makefile
 > +++ b/Makefile
 > @@ -26,7 +26,7 @@
 
 >  # Trick for always running with a fixed umask
 >  UMASK = 0022
 > -ifneq ($(shell umask),$(UMASK))
 > +ifneq ($(shell printf "%04o\n" `umask`),$(UMASK))

Thanks, but with at least zsh this doesn't work:

zsh --version
zsh 5.0.7 (x86_64-pc-linux-gnu)

umask
022

printf "%04o\n" $(umask)
0026

It seems like the printf arguments are always handled as decimal.

It does work on bash though:

bash --version
GNU bash, version 4.3.33(1)-release (x86_64-pc-linux-gnu)
Copyright (C) 2013 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>

This is free software; you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

umask
0022

printf "%04o\n" $(umask)
0022

It seems we need to use the base#number syntax, E.G. 8#`umask` to get
zsh to interprete it as octal, but bash doesn't seem to like it :/

But the real question is why this happens in the first place? We do set
SHELL=bash, so all of this should be running under bash where it works.

What shell are you using and how is your setup?

-- 
Bye, Peter Korsgaard

[Buildroot] [PATCH] build: fix umask test

[Peter Korsgaard]

>>>>> "Peter" == Peter Korsgaard <peter@korsgaard.com> writes:

Hi,

 > It seems we need to use the base#number syntax, E.G. 8#`umask` to get
 > zsh to interprete it as octal, but bash doesn't seem to like it :/

 > But the real question is why this happens in the first place? We do set
 > SHELL=bash, so all of this should be running under bash where it works.

Sorry, I misremembered. This logic is above the line where we assign
bash to SHELL, so it runs with /bin/sh as shell. On my system, this is
dash and it behaves like bash in this regard. What shell do you use?

In any case, I think the proper fix is to simply move the SHELL= line
above here to ensure we get consistent results.

-- 
Bye, Peter Korsgaard

[Buildroot] [PATCH] build: fix umask test

[Thomas Petazzoni]

Hello,

On Mon, 30 May 2016 10:05:58 +0200, Peter Korsgaard wrote:

> Sorry, I misremembered. This logic is above the line where we assign
> bash to SHELL, so it runs with /bin/sh as shell. On my system, this is
> dash and it behaves like bash in this regard. What shell do you use?

From the Kurt's previous e-mails, I believe he is using mksh as his
shell.

Best regards,

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

[Buildroot] [PATCH] build: fix umask test

[Kurt Van Dijck]

> Hello,
> 
> On Mon, 30 May 2016 10:05:58 +0200, Peter Korsgaard wrote:
> 
> > Sorry, I misremembered. This logic is above the line where we assign
> > bash to SHELL, so it runs with /bin/sh as shell. On my system, this is
> > dash and it behaves like bash in this regard. What shell do you use?
> 
> From the Kurt's previous e-mails, I believe he is using mksh as his
> shell.

indeed, mksh it is.

I understand the zsh problem, on the other hand,
any number prefixed with a 0 is octal, isn't it?

Anyway, I'll re-think the patch too...

Kurt

[Buildroot] [PATCH] build: fix umask test

[Peter Korsgaard]

>>>>> "Thomas" == Thomas Petazzoni <thomas.petazzoni@free-electrons.com> writes:

 > Hello,
 > On Mon, 30 May 2016 10:05:58 +0200, Peter Korsgaard wrote:

 >> Sorry, I misremembered. This logic is above the line where we assign
 >> bash to SHELL, so it runs with /bin/sh as shell. On my system, this is
 >> dash and it behaves like bash in this regard. What shell do you use?

 > From the Kurt's previous e-mails, I believe he is using mksh as his
 > shell.

Yes, I noticed as well. I should stop reading my mails in reverse order
;)

-- 
Venlig hilsen,
Peter Korsgaard 

[Buildroot] [PATCH] build: fix umask test

[Peter Korsgaard]

>>>>> "Kurt" == Kurt Van Dijck <dev.kurt@vandijck-laurijssen.be> writes:

Hi,

 > I understand the zsh problem, on the other hand,
 > any number prefixed with a 0 is octal, isn't it?

Apparently not to zsh. I haven't found any official notice about it, but
googling around shows this (old!) patch:

http://www.zsh.org/mla/workers/1995/msg00518.html

 > Anyway, I'll re-think the patch too...

Just moving up the SHELL= line above this check should be enough.

-- 
Venlig hilsen,
Peter Korsgaard 

[Buildroot] [PATCH] build: fix umask test

[Kurt Van Dijck]

> 
> Hi,
> 
>  > I understand the zsh problem, on the other hand,
>  > any number prefixed with a 0 is octal, isn't it?
> 
> Apparently not to zsh. I haven't found any official notice about it, but
> googling around shows this (old!) patch:
> 
> http://www.zsh.org/mla/workers/1995/msg00518.html
> 
>  > Anyway, I'll re-think the patch too...
> 
> Just moving up the SHELL= line above this check should be enough.

I see, but how would that help when bash is not on the system?
Is bash a prerequisite?

I was thinking on using /bin/printf to avoid using the shell builtin.

Kurt

[Buildroot] [PATCH] build: fix umask test

[Arnout Vandecappelle]

On 05/30/16 23:09, Kurt Van Dijck wrote:
>>
>> Hi,
>>
>>  > I understand the zsh problem, on the other hand,
>>  > any number prefixed with a 0 is octal, isn't it?
>>
>> Apparently not to zsh. I haven't found any official notice about it, but
>> googling around shows this (old!) patch:
>>
>> http://www.zsh.org/mla/workers/1995/msg00518.html
>>
>>  > Anyway, I'll re-think the patch too...
>>
>> Just moving up the SHELL= line above this check should be enough.
> 
> I see, but how would that help when bash is not on the system?
> Is bash a prerequisite?

 Yes, bash is a prerequisite. Some of our own scripts are bash scripts.
Moreover, quite a few packages just assume that the shell is bash. Requiring
bash and setting is as SHELL is the simplest way to handle that.

> 
> I was thinking on using /bin/printf to avoid using the shell builtin.

 I don't have /bin/printf, only /usr/bin/printf...

 Regards,
 Arnout

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


-- 
Arnout Vandecappelle                          arnout at mind be
Senior Embedded Software Architect            +32-16-286500
Essensium/Mind                                http://www.mind.be
G.Geenslaan 9, 3001 Leuven, Belgium           BE 872 984 063 RPR Leuven
LinkedIn profile: http://www.linkedin.com/in/arnoutvandecappelle
GPG fingerprint:  7493 020B C7E3 8618 8DEC 222C 82EB F404 F9AC 0DDF

[Buildroot] [PATCH] build: fix umask test

[Kurt Van Dijck]

> > 
> > I see, but how would that help when bash is not on the system?
> > Is bash a prerequisite?
> 
>  Yes, bash is a prerequisite. Some of our own scripts are bash scripts.
> Moreover, quite a few packages just assume that the shell is bash. Requiring
> bash and setting is as SHELL is the simplest way to handle that.

The Makefile only recommends /bin/bash, it falls back to 'sh' when bash
is not present.

> 
> > 
> > I was thinking on using /bin/printf to avoid using the shell builtin.
> 
>  I don't have /bin/printf, only /usr/bin/printf...

Thanks for mentioning, I'll address the problem without printf.

Kurt

[Buildroot] [PATCH] build: fix umask test

[Peter Korsgaard]

>>>>> "Kurt" == Kurt Van Dijck <dev.kurt@vandijck-laurijssen.be> writes:

 >> > 
 >> > I see, but how would that help when bash is not on the system?
 >> > Is bash a prerequisite?
 >> 
 >> Yes, bash is a prerequisite. Some of our own scripts are bash scripts.
 >> Moreover, quite a few packages just assume that the shell is bash. Requiring
 >> bash and setting is as SHELL is the simplest way to handle that.

 > The Makefile only recommends /bin/bash, it falls back to 'sh' when bash
 > is not present.

Yes, but support/dependencies/dependencies.sh checks for bash and bails
out if not available.

-- 
Venlig hilsen,
Peter Korsgaard 

[Buildroot] [PATCH] build: fix umask test

[Kurt Van Dijck]

> >>>>> "Kurt" == Kurt Van Dijck <dev.kurt@vandijck-laurijssen.be> writes:
> 
>  >> > 
>  >> > I see, but how would that help when bash is not on the system?
>  >> > Is bash a prerequisite?
>  >> 
>  >> Yes, bash is a prerequisite. Some of our own scripts are bash scripts.
>  >> Moreover, quite a few packages just assume that the shell is bash. Requiring
>  >> bash and setting is as SHELL is the simplest way to handle that.
> 
>  > The Makefile only recommends /bin/bash, it falls back to 'sh' when bash
>  > is not present.
> 
> Yes, but support/dependencies/dependencies.sh checks for bash and bails
> out if not available.

I wasn't aware of this :-)

I already sent out a v2 of the patch which makes it shell-independant.

Kurt