Re: [PATCH 1/2] patch: special-case quilt in debian

[Henning Schild <henning.schild@siemens.com>]

Patching has always been a huge pain, please test this and let me know
if it works for your layers.

Henning

On Tue, 28 Jul 2020 22:31:52 +0200
Henning Schild <henning.schild@siemens.com> wrote:

> From: Henning Schild <henning.schild@siemens.com>
> 
> The OE patch lib uses quilt and so do many debian packages as well.
> Those two do not work well together, it is really hard to create a
> patch that will apply and not break what debian does later. debian is
> very pedantic about unexpected changes so even if patching works,
> building might not.
> 
> Introduce a special-case where we detect quilt usage of a debian
> package and hook in there. Also make sure we are on top of debian so
> we do not risk breaking patches we inherit from there.
> 
> If anyone ever managed to create a patch that works well in the face
> of two quilts, that might break with this change. You can set
> PATCHTOOL to "quilt" in your recipe to disable the magic.
> 
> Signed-off-by: Henning Schild <henning.schild@siemens.com>
> ---
>  meta/classes/patch.bbclass | 28 ++++++++++++++++++++++++++++
>  1 file changed, 28 insertions(+)
> 
> diff --git a/meta/classes/patch.bbclass b/meta/classes/patch.bbclass
> index 3060755a5c..06f32a2197 100644
> --- a/meta/classes/patch.bbclass
> +++ b/meta/classes/patch.bbclass
> @@ -91,6 +91,28 @@ def should_apply(parm, d):
>  
>  should_apply[vardepsexclude] = "DATE SRCDATE"
>  
> +def patch_do_debian_quilt(patchdir, d):
> +    import oe.patch
> +    class DummyPatchSet(oe.patch.PatchSet):
> +        def Clean(self):
> +            True
> +
> +        def Import(self, patch, force):
> +            os.putenv('QUILT_PATCHES', 'debian/patches')
> +            # push all so we are on top of debian
> +            pushed = False
> +            if os.path.exists(os.path.join(self.dir,
> 'debian/patches/series')):
> +                oe.patch.runcmd(["quilt", "push", "-a"], self.dir)
> +                pushed = True
> +            oe.patch.runcmd(["quilt", "import", "-f",
> os.path.join(d.getVar('WORKDIR'), os.path.basename(patch['file']))],
> self.dir)
> +            if pushed:
> +                oe.patch.runcmd(["quilt", "pop", "-a"], self.dir)
> +
> +        def Push(self, force = False):
> +            True
> +
> +    return DummyPatchSet(patchdir, d)
> +
>  python patch_do_patch() {
>      import sys
>  
> @@ -118,6 +140,12 @@ python patch_do_patch() {
>  
>      s = d.getVar('S')
>  
> +    debianformat = os.path.join(s, 'debian/source/format')
> +    if os.path.exists(debianformat) and d.getVar('PATCHTOOL') !=
> 'quilt':
> +        with open(debianformat, 'r+') as f:
> +            if f.readline() == '3.0 (quilt)\n':
> +                cls = patch_do_debian_quilt
> +
>      os.putenv('PATH', d.getVar('PATH'))
>  
>      # We must use one TMPDIR per process so that the "patch"
> processes