From mboxrd@z Thu Jan  1 00:00:00 1970
From: Yann E. MORIN <yann.morin.1998@free.fr>
Date: Tue, 22 Jun 2021 22:50:40 +0200
Subject: [Buildroot] [PATCH 09/15] package/pkg-python: Remove
 _sysconfigdata*.pyc files when _sysconfigdata*.py are changed
In-Reply-To: <20210622195211.4bafd222@bootlin.com>
References: <20210621141130.48654-1-herve.codina@bootlin.com>
 <20210621141130.48654-10-herve.codina@bootlin.com>
 <20210621171202.2362cb27@windsurf>
 <20210622195211.4bafd222@bootlin.com>
Message-ID: <20210622205040.GM44262@scaer>
List-Id: <buildroot.busybox.net>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
To: buildroot@busybox.net

Herv?, All,

On 2021-06-22 19:52 +0200, Herve Codina spake thusly:
> On Mon, 21 Jun 2021 17:12:02 +0200
> Thomas Petazzoni <thomas.petazzoni@bootlin.com> wrote:
> > On Mon, 21 Jun 2021 16:11:24 +0200
> > Herve Codina <herve.codina@bootlin.com> wrote:
> > > In order to avoid _sysconfigdata*.pyc overwrites when they are generated based on
> > > _sysconfigdata*.py changes, this commit simply removes _sysconfigdata*.pyc
> > > whenever _sysconfigdata*.py are changed.
> > > 
> > > As they are removed, overwrite detection will no longer trig and coherency between
> > > the two files (.py and .pyc) is ensured.
> > > 
> > > Signed-off-by: Herve Codina <herve.codina@bootlin.com>
> > > ---
> > >  package/pkg-python.mk | 4 +++-
> > >  1 file changed, 3 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/package/pkg-python.mk b/package/pkg-python.mk
> > > index 59a48e5a87..b3fde77da5 100644
> > > --- a/package/pkg-python.mk
> > > +++ b/package/pkg-python.mk
> > > @@ -96,7 +96,9 @@ ifeq ($(BR2_PER_PACKAGE_DIRECTORIES),y)
> > >  define PKG_PYTHON_FIXUP_SYSCONFIGDATA
> > >  	find $(HOST_DIR)/lib/python* $(STAGING_DIR)/usr/lib/python* \
> > >  		-name "_sysconfigdata*.py" | xargs --no-run-if-empty \
> > > -		$(SED) "s:$(PER_PACKAGE_DIR)/[^/]\+/:$(PER_PACKAGE_DIR)/$($(PKG)_NAME)/:g"
> > > +		$(SED) "s:$(PER_PACKAGE_DIR)/[^/]\+/:$(PER_PACKAGE_DIR)/$($(PKG)_NAME)/:g" ;\  
[--SNIP--]
> > > +	find $(HOST_DIR)/lib/python* $(STAGING_DIR)/usr/lib/python* \
> > > +		-name "_sysconfigdata*.pyc" -print0 | xargs -0 -r rm -f  
> > Do we need a --no-run-if-empty on the xargs ? Or perhaps it should be
> It is cleaner to avoid running rm is there is nothing to remove.
> So, I prefer keeping the xargs -r option.
> 
> > using find directly, i.e:
> > 
> > 	find $(HOST_DIR)/lib/python* $(STAGING_DIR)/usr/lib/python* \
> > 		-name "_sysconfigdata*.pyc" -exec rm -f {} \;
> > 
> > (or something like that)
> 
> Using "-exec rm -f {} \;" will lead to start as many rm as there are files
> to remove whereas xargs will run only one rm.

So, 1: wrong. xargs may have to exec more than one rm if there are too
many arguments, or the command line is too long. But of course, this is
inconsequential, because even on a huge build, this would be just a few
exec instead of tens of thousands.

And 2: why not using find's -delete option to begin with:

    find $(HOST_DIR)/lib/python* $(STAGING_DIR)/usr/lib/python* \
        -name "_sysconfigdata*.pyc" -delete

There, not even a pipe, or an exec of anything else...

Regards,
Yann E. MORIN.

> 
> Herv?
> 
> -- 
> Herv? Codina, Bootlin
> Embedded Linux and Kernel engineering
> https://bootlin.com
> _______________________________________________
> buildroot mailing list
> buildroot at busybox.net
> http://lists.busybox.net/mailman/listinfo/buildroot

-- 
.-----------------.--------------------.------------------.--------------------.
|  Yann E. MORIN  | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +33 662 376 056 | Software  Designer | \ / CAMPAIGN     |  ___               |
| +33 561 099 427 `------------.-------:  X  AGAINST      |  \e/  There is no  |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
'------------------------------^-------^------------------^--------------------'