Re: [PATCH 1/6] scripts/bitbake: ensure user is in build directory

[Andreas Oberritter <obi@opendreambox.org>]

On 16.03.2012 00:09, Paul Eggleton wrote:
> On Thursday 15 March 2012 01:30:31 Andreas Oberritter wrote:
>> On 14.03.2012 01:36, Paul Eggleton wrote:
>>> If the user is in any directory other than $BUILDDIR when the bitbake
>>> wrapper script is run, then show an error an exit.
>>
>> this patch broke my setup.
> 
> Ah, sorry about that.
>  
>> My $BUILDDIR points to tmp, so that pseudo doesn't get rebuilt for every
>> machine. I have a shared tmp for many machines.
> 
> So a couple of things:
> 
> 1) Unless I'm missing something you can share the same TMPDIR between multiple 
> build directories to get the same result.
>  
> 2) pseudo is a native package. It shouldn't be rebuilt when changing MACHINE. 
> In fact I just verified by creating a different build directory with only 
> MACHINE changed in the config, it is not rebuilt.

Sorry, I messed up some details. In fact, pseudo-native doesn't get
rebuilt, but bitbake pseudo-native still gets executed for every
machine, unless $BUILDDIR/pseudodone is present and contains
PSEUDOBINDIR. This just wastes time and confuses users who receive a
message saying "Pseudo is not present but is required, building this
first before the main build".

>> BUILDDIR doesn't seem to have any other use than pointing to the
>> 'pseudodone' file. I don't understand why it's required to run bitbake
>> from there.
> 
> Well, it's required that bitbake is run from the build directory and when you 
> use the setup script as intended that's where BUILDDIR points to. I hadn't 
> anticipated that anyone would be changing BUILDDIR to point to anything other 
> than the build dir, however I don't really think it's a good idea to support 
> that.

That's because BUILDDIR has no meaning outside oe-core's setup scripts.
In scripts/bitbake, BUILDDIR would better be called PSEUDODONEDIR or
similar, because that's what the variable really means in this context
[1]. If I had a choice to override a more suitably named variable I
certainly would do that. ;-)

In order to verify that scripts/bitbake is called from the build
directory, you could as well just check whether $PWD/conf/local.conf exists.

I'm not using oe-core's scripts, because they make assumptions about the
directory layout that don't fit my project's needs. I think they are
overly complex and they display texts that seem to suit yocto's needs
but at least not mine.

Regards,
Andreas

[1]
$ grep BUILDDIR scripts/bitbake
if [ $needpseudo = "1" ] && [ -e "$BUILDDIR/pseudodone" ]; then
    PSEUDOBINDIR=`cat $BUILDDIR/pseudodone`
    echo $PSEUDOBINDIR > $BUILDDIR/pseudodone
    PSEUDOBINDIR=`cat $BUILDDIR/pseudodone`