[Buildroot] [PATCH 0/4 v2] core: add host-gzip for cvs/git/svn backends

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

Hello All!

As reported a few times already, gzip on some systems is aliased to
pigz, a parallel implementation of gzip that takes advantage of
multi-{processor,core,thread} systems to compress in parallel.

However, the compressed streams generated by pigz, even though they are
valid gzip streams, differ for the streams generated by gzip. In fact,
this is caused by pigz adding more checksums than is done by gzip, and
because the streams are arbitrarily cut in blocks, the coder starts in
different conditions for each blocks.

So, add a host variant to gzip, and use that as a download dependency
for packages that need to create compressed tarballs (cvs, git, and
svn).

While at it, do two seemingly unrelated cleanups: both where noticed
while investigating how to do the last patch (i.e. the questions were:
How do we handle tar so I just copy that? -> noticed the tar comments.
Then, should I export GZIP? If so, where? -> noticed SSH.)


Regards,
Yann E. MORIN.


The following changes since commit 915c136c5c9abeb683b59fad4a0e05a25c1a1cc2

  package/openocd: add missing host-pkgconf dependency (2018-11-16 23:28:50 +0100)


are available in the git repository at:

  git://git.buildroot.org/~ymorin/git/buildroot.git

for you to fetch changes up to ba548d03f79279b7f02605006a709ffc630e8639

  support/dependencies: add a check for a suitable gzip (2018-11-17 18:12:51 +0100)


----------------------------------------------------------------
Yann E. MORIN (4):
      core/download: drop the SSH command
      support/dependencies: treat BSD-tar like the other cases
      package/gzip: add host variant
      support/dependencies: add a check for a suitable gzip

 Config.in                               |  4 ----
 package/gzip/gzip.mk                    |  2 ++
 package/pkg-download.mk                 |  1 -
 package/pkg-generic.mk                  |  4 +++-
 support/dependencies/check-host-gzip.mk |  3 +++
 support/dependencies/check-host-gzip.sh | 21 +++++++++++++++++++++
 support/dependencies/check-host-tar.sh  |  9 +++++----
 7 files changed, 34 insertions(+), 10 deletions(-)
 create mode 100644 support/dependencies/check-host-gzip.mk
 create mode 100755 support/dependencies/check-host-gzip.sh

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