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download/git: force gzip compression level 6

PATCH New Petr Kulhavy 3 participants 6 messages Sep 11, 2017 – Oct 16, 2017

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#0 lore raw

PATCH 1/1 download/git: force gzip compression level 6

Force gzip compression level 6 when calculating hash of a downloaded GIT repo. To make sure the tar->gzip->checksum chain always provides consistent result.`

The script was relying on the default compression level, which must not be necessarily consistent among different gzip versions. The level 6 is gzip's current default compression level.

---
 support/download/git | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
support/download/git +1 -1
index fc2957d..f590ff6 100755
@@ -101,4 +101,4 @@ LC_ALL=C sort <"${basename}.list" >"${basename}.list.sorted"
 # sources.buildroot.org and used in the *.hash files
 tar cf - --numeric-owner --owner=0 --group=0 --mtime="${date}" --format=gnu \
          -T "${basename}.list.sorted" >"${output}.tar"
-gzip -n <"${output}.tar" >"${output}"
+gzip -6 -n <"${output}.tar" >"${output}"
Signature · 1 line
2.7.4
#1 lore raw

PATCH 1/1 download/git: force gzip compression level 6

Petr, All,

On 2017-09-12 00:13 +0200, Petr Kulhavy spake thusly:

Quoted 6 lines

Force gzip compression level 6 when calculating hash of a downloaded GIT repo. To make sure the tar->gzip->checksum chain always provides consistent result.`

The script was relying on the default compression level, which must not be necessarily consistent among different gzip versions. The level 6 is gzip's current default compression level.

Not only is it the _current_ default, it has always been so since the first release.

Quoted 1 line

Regards,
Yann E. MORIN.

Quoted 17 lines
---
 support/download/git | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
support/download/git +1 -1
index fc2957d..f590ff6 100755
@@ -101,4 +101,4 @@ LC_ALL=C sort <"${basename}.list" >"${basename}.list.sorted"
 # sources.buildroot.org and used in the *.hash files
 tar cf - --numeric-owner --owner=0 --group=0 --mtime="${date}" --format=gnu \
          -T "${basename}.list.sorted" >"${output}.tar"
-gzip -n <"${output}.tar" >"${output}"
+gzip -6 -n <"${output}.tar" >"${output}"
Signature · 1 line
2.7.4
Signature · 6 lines
.-----------------.--------------------.------------------.--------------------.
|  Yann E. MORIN  | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +33 662 376 056 | Software  Designer | \ / CAMPAIGN     |  ___               |
| +33 223 225 172 `------------.-------:  X  AGAINST      |  \e/  There is no  |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
'------------------------------^-------^------------------^--------------------'
#2 lore raw

PATCH 1/1 download/git: force gzip compression level 6

In reply to Petr Kulhavy
Quoted 8 lines
Quoted 1 line
Quoted 1 line
Quoted 1 line
Quoted 1 line

"Petr" == Petr Kulhavy <[email protected]> writes:

Force gzip compression level 6 when calculating hash of a downloaded GIT repo. To make sure the tar->gzip->checksum chain always provides consistent result.`

The script was relying on the default compression level, which must not be necessarily consistent among different gzip versions. The level 6 is gzip's current default compression level.

Committed, thanks.

Is this just a theoretical issue, or something you have really run into?

Signature · 1 line
Bye, Peter Korsgaard
#3 lore raw

PATCH 1/1 download/git: force gzip compression level 6

Peter, All,

On 2017-09-12 23:36 +0200, Peter Korsgaard spake thusly:

Quoted 5 lines
Quoted 4 lines
Quoted 1 line
Quoted 1 line
Quoted 1 line
Quoted 1 line

"Petr" == Petr Kulhavy <[email protected]> writes:

Force gzip compression level 6 when calculating hash of a downloaded GIT repo. To make sure the tar->gzip->checksum chain always provides consistent result.`

Quoted 7 lines
Quoted 3 lines

The script was relying on the default compression level, which must not be necessarily consistent among different gzip versions. The level 6 is gzip's current default compression level.

Committed, thanks.

Is this just a theoretical issue, or something you have really run into?

Theoretical, see this mail and the ensuing discussion:

    http://lists.busybox.net/pipermail/buildroot/2017-September/202162.html

Yet, for consistency, it is good to force it.

Regards,
Yann E. MORIN.

Signature · 6 lines
.-----------------.--------------------.------------------.--------------------.
|  Yann E. MORIN  | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +33 662 376 056 | Software  Designer | \ / CAMPAIGN     |  ___               |
| +33 223 225 172 `------------.-------:  X  AGAINST      |  \e/  There is no  |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
'------------------------------^-------^------------------^--------------------'
#4 lore raw

PATCH 1/1 download/git: force gzip compression level 6

In reply to Petr Kulhavy
Quoted 10 lines
Quoted 1 line
Quoted 1 line
Quoted 1 line
Quoted 1 line

"Petr" == Petr Kulhavy <[email protected]> writes:

Force gzip compression level 6 when calculating hash of a downloaded GIT repo. To make sure the tar->gzip->checksum chain always provides consistent result.`

The script was relying on the default compression level, which must not be necessarily consistent among different gzip versions. The level 6 is gzip's current default compression level.

Committed to 2017.02.x, thanks.

Signature · 1 line
Bye, Peter Korsgaard
#5 lore raw

PATCH 1/1 download/git: force gzip compression level 6

In reply to Petr Kulhavy
Quoted 10 lines
Quoted 1 line
Quoted 1 line
Quoted 1 line
Quoted 1 line

"Petr" == Petr Kulhavy <[email protected]> writes:

Force gzip compression level 6 when calculating hash of a downloaded GIT repo. To make sure the tar->gzip->checksum chain always provides consistent result.`

The script was relying on the default compression level, which must not be necessarily consistent among different gzip versions. The level 6 is gzip's current default compression level.

Committed to 2017.08.x, thanks.

Signature · 1 line
Bye, Peter Korsgaard