Re: [PATCH 3/3] dpkg-gbp: default to "git" patching

[Jan Kiszka <jan.kiszka@siemens.com>]

On 11.08.21 20:36, Henning Schild wrote:
> Am Wed, 11 Aug 2021 20:14:56 +0200
> schrieb Jan Kiszka <jan.kiszka@siemens.com>:
> 
>> On 22.01.21 11:55, [ext] Jan Kiszka wrote:
>>> On 22.01.21 09:42, [ext] Henning Schild wrote:  
>>>> From: Henning Schild <henning.schild@siemens.com>
>>>>
>>>> That class is about packages coming from git, so that is the
>>>> natural choice for the patching tool.
>>>>
>>>> Signed-off-by: Henning Schild <henning.schild@siemens.com>
>>>> ---
>>>>  RECIPE-API-CHANGELOG.md                    | 5 +++++
>>>>  meta-isar/recipes-app/cowsay/cowsay_git.bb | 1 -
>>>>  meta/classes/dpkg-gbp.bbclass              | 2 ++
>>>>  3 files changed, 7 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/RECIPE-API-CHANGELOG.md b/RECIPE-API-CHANGELOG.md
>>>> index cc45f3f66e..c4ec5894a8 100644
>>>> --- a/RECIPE-API-CHANGELOG.md
>>>> +++ b/RECIPE-API-CHANGELOG.md
>>>> @@ -282,3 +282,8 @@ like /boot/efi to avoid such issues.
>>>>  ### Deprecate BUILD_DEPENDS in u-boot-custom.inc
>>>>  
>>>>  Use DEBIAN_BUILD_DEPENDS instead, to align with deb_debianize.
>>>> +
>>>> +### Default to PATCHTOOL ?= "git" for dpkg-gbp
>>>> +
>>>> +Migrate your patches so they can be applied with "git am", or
>>>> +"unset PATCHTOOL" to get old behaviour.
>>>> diff --git a/meta-isar/recipes-app/cowsay/cowsay_git.bb
>>>> b/meta-isar/recipes-app/cowsay/cowsay_git.bb index
>>>> 2e885a8aa3..c3a1f4942a 100644 ---
>>>> a/meta-isar/recipes-app/cowsay/cowsay_git.bb +++
>>>> b/meta-isar/recipes-app/cowsay/cowsay_git.bb @@ -5,7 +5,6 @@
>>>>  
>>>>  inherit dpkg-gbp
>>>>  
>>>> -PATCHTOOL = "git"
>>>>  SRC_URI =
>>>> "git://salsa.debian.org/debian/cowsay.git;protocol=https" SRC_URI
>>>> += "file://isar.patch" SRCREV =
>>>> "756f0c41fbf582093c0c1dff9ff77734716cb26f" diff --git
>>>> a/meta/classes/dpkg-gbp.bbclass b/meta/classes/dpkg-gbp.bbclass
>>>> index ba5c3ebb89..d956e8c3bc 100644 ---
>>>> a/meta/classes/dpkg-gbp.bbclass +++ b/meta/classes/dpkg-gbp.bbclass
>>>> @@ -7,6 +7,8 @@ inherit dpkg
>>>>  
>>>>  S = "${WORKDIR}/git"
>>>>  
>>>> +PATCHTOOL ?= "git"
>>>> +
>>>>  GBP_DEPENDS ?= "git-buildpackage pristine-tar"
>>>>  GBP_EXTRA_OPTIONS ?= "--git-pristine-tar"
>>>>  
>>>>  
>>>
>>> Sounds reasonable to me.
>>>   
>>
>> ...but breaks rebuilding as long as we do not clone into the
>> buildchroot and rather patch alternates:
>>
>> ERROR: mc:qemuarm64-buster:cowsay-git-r0 do_patch: Command Error: 'sh
>> -c 'git
>> --work-tree=/build/tmp/work/debian-buster-arm64/cowsay/git-r0/git
>> reset --hard HEAD'' exited with 0  Output: error: object directory
>> /downloads/git/salsa.debian.org.debian.cowsay.git/objects does not
>> exist; check .git/objects/info/alternates error: unable to read sha1
>> file of cows/elephant-in-snake.cow
>> (1003cdf63bd9ae64e6674b47f8ed4799b5f809a6) error: unable to read sha1
>> file of cows/elephant.cow (959cd3f6dd2b628b2471572a06e162b31dbcac96)
>> error: unable to read sha1 file of cows/head-in.cow
>> (2e51774886392c2d295e5659b03dbfa04f14aeb4) error: unable to read sha1
>> file of cows/luke-koala.cow
>> (78acd6988fa397cc1dfcd98f04373af94288430e) error: unable to read sha1
>> file of cows/moofasa.cow (15119d6782fec20424c648fcf0174f291dd22026)
>> error: unable to read sha1 file of cowsay
>> (900ca46014cf0454075a6390830b399b2a4b2a34) error: unable to read sha1
>> file of cowsay.1 (7133866af2f7ea7cccdfa79378a61b27c1573e6b) fatal:
>> Could not reset index file to revision 'HEAD'. ERROR: Logfile of
>> failure stored in:
>> /build/tmp/work/debian-buster-arm64/cowsay/git-r0/temp/log.do_patch.71
>> ERROR: Task
>> (mc:qemuarm64-buster:/repo/meta-isar/recipes-app/cowsay/cowsay_git.bb:do_patch)
>> failed with exit code '1'
>>
>> Did this change have a practical motivation or was just out of
>> esthetic reasons? If it were only the latter, we should revert until
>> our bitbake can resolve the underlying problem.
> 
> It does have a practical motivation. Patching with quilt in isar has
> nasty side-effects when debian/ is using quilt as well.
> Using git as patchtool when git is also doing fetch/unpack seems like
> the best solution to that. The patching with quilt gets especially
> nasty if you can not add a quilt patch-patch to just deal with the code
> ... when you find yourself also wanting to patch debian/.
> 
> I would say that "adjust_git" is to blame here and we need to live with
> that until we version-bump bitbake. In recent bitbake we will have
> https://github.com/openembedded/bitbake/commit/6ae6f1865d5e666ebc670f70b7401a7b41648102
> and will be able to ditch "adjust_git" by simply setting a global
> BB_GIT_NOSHARED for isar.
> That will also result in much improved usability ... since git repos
> will end up usable insisde/outside chroots.

That reasoning was missing from the commit log, and also the cover
letter declared this patch optional.

But you can patch debian packages via quilt, though not by do_patch
directly, see various examples in our layers. So the reasoning needs to
be a bit more precises in pointing out that also this approach did not
work (and ideally why).

Jan

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