Bug#703995: apt-setup: preseeding apt-setup/multiarch breaks dpkg

[Raphaël Hertzog <hertzog@debian.org>]

Package: apt-setup
Version: 0.77
Severity: normal
Tags: patch

I wanted to try out preseeding apt-setup/multiarch to i386 but before
doing it, I reviewed apt-setup's handling of this option and I discovered
that it actually creates the configuration file used by the early Ubuntu
implementation of multiarch (which relied on the --foreign-architecture
command line option instead of the single dpkg --add-architecture call).
This means that it actually breaks dpkg since the current version of dpkg
doesn't underestand the --foreign-architecture command-line option.

Here's an untested patch:

--- a/generators/01setup
+++ b/generators/01setup
@@ -17,8 +17,7 @@ fi
 
 db_get apt-setup/multiarch
 if [ "$RET" ]; then
-       mkdir -p $ROOT/etc/dpkg/dpkg.cfg.d
        for arch in $RET; do
-               echo "foreign-architecture $arch"
-       done >$ROOT/etc/dpkg/dpkg.cfg.d/multiarch
+               chroot $ROOT dpkg --add-architecture $arch
+       done
 fi

IMO it would be nice to have this fixed in wheezy but it's not required
either.

Cheers,

-- System Information:
Debian Release: 7.0
  APT prefers unstable
  APT policy: (500, 'unstable'), (500, 'testing'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 3.7-trunk-amd64 (SMP w/4 CPU cores)
Locale: LANG=fr_FR.UTF-8, LC_CTYPE=fr_FR.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash