[gentoo-dev] meaning of EROOT

[gentoo-dev] meaning of EROOT

[heroxbd]

Dear All,

I am a bit confused with the meaning of EROOT.

In a usual Prefix installation, ROOT=/ and EPREFIX=/opt/gentoo,
EROOT=/opt/gentoo/.

Naturally, EROOT=${EPREFIX}${ROOT}, right?

But for example in ./python.eclass

    EROOT="${ROOT%/}${EPREFIX}/"

and in LocationsManager.py of portage

    self.eroot = self.target_root.rstrip(os.sep) + self.eprefix + os.sep

What is the logic behind this construction?

The problem rises when I want to cross-compile under Prefix. Taking
armv7a-hardfloat-linux-gnueabi for example,
ROOT=/usr/armv7a-hardfloat-linux-gnueabi/, EPREFIX=/opt/gentoo. I'd
expect EROOT to be ${EPREFIX}${ROOT}, therefore,
/opt/gentoo/usr/armv7a-hardfloat-linux-gnueabi/. At present
EROOT=/usr/armv7a-hardfloat-linux-gnueabi/opt/gentoo/, which is
completely useless.

Cheers,
Benda

Re: [gentoo-dev] meaning of EROOT

[Zac Medico]

On 02/03/2013 03:07 AM, heroxbd wrote:
> Dear All,
> 
> I am a bit confused with the meaning of EROOT.
> 
> In a usual Prefix installation, ROOT=/ and EPREFIX=/opt/gentoo,
> EROOT=/opt/gentoo/.
> 
> Naturally, EROOT=${EPREFIX}${ROOT}, right?

No, it's EROOT=${ROOT%/}${EPREFIX}/

> But for example in ./python.eclass
> 
>     EROOT="${ROOT%/}${EPREFIX}/"
> 
> and in LocationsManager.py of portage
> 
>     self.eroot = self.target_root.rstrip(os.sep) + self.eprefix + os.sep
> 
> What is the logic behind this construction?

ROOT corresponds to a valid chroot point. EPREFIX is an offset inside a
valid chroot point.

> The problem rises when I want to cross-compile under Prefix. Taking
> armv7a-hardfloat-linux-gnueabi for example,
> ROOT=/usr/armv7a-hardfloat-linux-gnueabi/, EPREFIX=/opt/gentoo. I'd
> expect EROOT to be ${EPREFIX}${ROOT}, therefore,
> /opt/gentoo/usr/armv7a-hardfloat-linux-gnueabi/. At present
> EROOT=/usr/armv7a-hardfloat-linux-gnueabi/opt/gentoo/, which is
> completely useless.

You've filed this bug on the same topic:

  https://bugs.gentoo.org/show_bug.cgi?id=395633

We should continue there.
-- 
Thanks,
Zac

Re: [gentoo-dev] meaning of EROOT

[Michael Weber]

On 02/03/2013 12:07 PM, heroxbd wrote:
>     self.eroot = self.target_root.rstrip(os.sep) + self.eprefix + os.sep
wouldn't be this more robust

>>> import os
>>> os.path.normpath('/some/' + os.path.sep + '/stuff/') + os.path.sep
'/some/stuff/'


-- 
Michael Weber
Gentoo Developer
web: https://xmw.de/
mailto: Michael Weber <xmw@gentoo.org>

Re: [gentoo-dev] meaning of EROOT

[Zac Medico]

On 02/04/2013 03:01 AM, Michael Weber wrote:
> On 02/03/2013 12:07 PM, heroxbd wrote:
>>     self.eroot = self.target_root.rstrip(os.sep) + self.eprefix + os.sep
> wouldn't be this more robust
> 
>>>> import os
>>>> os.path.normpath('/some/' + os.path.sep + '/stuff/') + os.path.sep
> '/some/stuff/'

In this context, the relevant paths have already been normalized earlier.
-- 
Thanks,
Zac