[Buildroot] [PATCH] core: do not remove dl/ directory on distclean

[Yann E. MORIN <yann.morin.1998@free.fr>]

Peter, All,

On 2016-07-11 22:03 +0200, Peter Korsgaard spake thusly:
> >>>>> "Yann" == Yann E MORIN <yann.morin.1998@free.fr> writes:
>  > Baruch, All,
>  > On 2016-07-11 06:26 +0300, Baruch Siach spake thusly:
>  >> On Sun, Jul 10, 2016 at 11:55:49PM +0200, Yann E. MORIN wrote:
>  >> > Currently, if the dl/ directory is the default location, it is removed
>  >> > on distclean.
>  >> > 
>  >> > However, the dl/ directory is a precious location: it contains all the
>  >> > tarballs downloaded so far, and some can be relatively huge, taking some
>  >> > previous time to re-download, especially on slowish links.
>  >> > 
>  >> > Don't remove it on distclean. If the user really needs to regain some
>  >> > space, leave it to him to clean this directory up manually.
>  >> 
>  >> Current Makefile help text for 'distclean' says:
>  >> 
>  >> delete all non-source files (including .config)
>  >> 
>  >> Not deleting the dl/ directory is not consistent with this description, IMO.
> 
>  > Well, I do understand it the other way: non-source files are deleted,
>  > but source files are not deleted.
> 
>  > And I would argue that the content of dl/ *are* source files. If
>  > anything, they are the archetype of source files.
> 
>  > Ergo, distclean should not remove them.
> 
> Sorry, I agree with Baruch. Distclean should leave the directory
> structure like it was when the buildroot tarball was extracted (or git
> cloned)

Right, on principle. Except...

> E.G. the GNU standard make targets state:
> 
> https://www.gnu.org/prep/standards/standards.html#Standard-Targets
> 
> ?distclean?
> 
> Delete all files in the current directory (or created by this makefile)
> that are created by configuring or building the program. If you have
> unpacked the source and built the program without creating any other
> files, ?make distclean? should leave only the files that were in the
> distribution. However, there is no need to delete parent directories
> that were created with ?mkdir -p?, since they could have existed anyway.

... we could (should?) consider that dl/ is a special case. It really
holds content that can be difficult to retrieve.

Think of a tarball made from a git clone from a Linux kernel for
example. This can be really costly to download, especially on slow
links. For example:

Downloaded  Repo
-----------------------------------------------------------------------------
1.02 GiB    git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
1.43 GiB    git://github.com/raspberrypi/linux.git


But Oh well... I'm not impacted as I have BR2_DL_DIR in my environment
pointing somehwere else and reliable... I find it just sad that
unsuspecting users, especially newcomers) would hit that when told to
start over from scratch...

Regards,
Yann E. MORIN.

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