Bug#1104537: binfmtc: fails to install: postinst depends on update-binfmts

[Michael Biebl <biebl@debian.org>]

Hi


Am 01.05.25 um 19:29 schrieb Santiago Vila:
> El 1/5/25 a las 19:16, Paul Gevers escribió:
> > Package: binfmtc
> > Version: 0.17-3
> > Severity: serious
> > Justification: fails to install
> >
> > Hi,
> >
> > I just saw this on one of my hosts:
> >
> > $ sudo apt install -f
> > Summary:
> >    Upgrading: 0, Installing: 0, Removing: 0, Not Upgrading: 427
> >    1 not fully installed or removed.
> >    Space needed: 0 B / 140 GB available
> >
> > Setting up binfmtc (0.17-3) ...
> > /var/lib/dpkg/info/binfmtc.postinst: 6: update-binfmts: not found
> > dpkg: error processing package binfmtc (--configure):
> >   installed binfmtc package post-installation script subprocess 
> > returned error exit status 127
> > Errors were encountered while processing:
> >   binfmtc
> > needrestart is being skipped since dpkg has failed
> > Error: Sub-process /usr/bin/dpkg returned an error code (1)
>
> I think this was introduced in commit [226f58c], where the Depends
> line was changed from "binfmt-support" to "binfmt-support | systemd".
>
> Question for Michael: Is systemd supposed to provide another alternative
> implementation of "update-binfmts"? Or maybe postinst should
> do nothing when systemd is present?

There is a trigger for systemd-binfmt:

https://salsa.debian.org/systemd-team/systemd/-/blob/debian/master/debian/systemd.postinst?ref_type=heads#L48


So, I'd say just make the code that runs update-binfmts conditional on 
the presence of the update-binfmts binary. Something like the attached 
(untested) patch.

Michael





diff --git a/debian/binfmtc.postinst b/debian/binfmtc.postinst
index 0bcfc04..55d52c4 100644
--- a/debian/binfmtc.postinst
+++ b/debian/binfmtc.postinst
@@ -2,7 +2,7 @@
 set -e
 
 #import binfmt.
-if [ configure = "$1" ]; then
+if [ configure = "$1" ] && [ -x "$(command -v update-binfmts)" ]; then
     update-binfmts --import ccompile
     update-binfmts --import cxxcompile
     update-binfmts --import asmassembly
diff --git a/debian/binfmtc.postrm b/debian/binfmtc.postrm
index 8c0098a..a15102d 100644
--- a/debian/binfmtc.postrm
+++ b/debian/binfmtc.postrm
@@ -2,7 +2,7 @@
 set -e
 
 #remove binfmt
-if [ remove = "$1" ]; then
+if [ remove = "$1" ] && [ -x "$(command -v update-binfmts)" ]; then
     update-binfmts --package binfmtc --remove ccompile /usr/bin/binfmtc-interpreter
     update-binfmts --package binfmtc --remove cxxcompile /usr/bin/binfmtcxx-interpreter
     update-binfmts --package binfmtc --remove asmassembly /usr/bin/binfmtasm-interpreter

Attachment: OpenPGP_signature.asc
Description: OpenPGP digital signature