[Qemu-devel] [PATCH-for-4.1] tests/docker: Install Ubuntu images noninteractively

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

We correctly use the DEBIAN_FRONTEND environment variable on
the Debian images, but forgot the Ubuntu ones are based on it.

Since building docker images is not interactive, we need to
inform the APT tools about it using the DEBIAN_FRONTEND
environment variable (we already use it on our Debian images).

This fixes:

  $ make docker-image-ubuntu V=1
  [...]
  Setting up tzdata (2019b-0ubuntu0.19.04) ...
  debconf: unable to initialize frontend: Dialog
  debconf: (TERM is not set, so the dialog frontend is not usable.)
  debconf: falling back to frontend: Readline
  Configuring tzdata
  ------------------

  Please select the geographic area in which you live. Subsequent configuration
  questions will narrow this down by presenting a list of cities, representing
  the time zones in which they are located.

    1. Africa      4. Australia  7. Atlantic  10. Pacific  13. Etc
    2. America     5. Arctic     8. Europe    11. SystemV
    3. Antarctica  6. Asia       9. Indian    12. US
  Geographic area: 12
  [HANG]

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 tests/docker/dockerfiles/ubuntu.docker     | 2 +-
 tests/docker/dockerfiles/ubuntu1804.docker | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/docker/dockerfiles/ubuntu.docker b/tests/docker/dockerfiles/ubuntu.docker
index d3b72209c8..f2fc1da6c5 100644
--- a/tests/docker/dockerfiles/ubuntu.docker
+++ b/tests/docker/dockerfiles/ubuntu.docker
@@ -65,6 +65,6 @@ ENV PACKAGES flex bison \
     texinfo \
     xfslibs-dev
 RUN apt-get update && \
-    apt-get -y install $PACKAGES
+    DEBIAN_FRONTEND=noninteractive apt-get -y install $PACKAGES
 RUN dpkg -l $PACKAGES | sort > /packages.txt
 ENV FEATURES clang pyyaml sdl2
diff --git a/tests/docker/dockerfiles/ubuntu1804.docker b/tests/docker/dockerfiles/ubuntu1804.docker
index 9d80b11500..d2d127340c 100644
--- a/tests/docker/dockerfiles/ubuntu1804.docker
+++ b/tests/docker/dockerfiles/ubuntu1804.docker
@@ -52,6 +52,6 @@ ENV PACKAGES flex bison \
     texinfo \
     xfslibs-dev
 RUN apt-get update && \
-    apt-get -y install $PACKAGES
+    DEBIAN_FRONTEND=noninteractive apt-get -y install $PACKAGES
 RUN dpkg -l $PACKAGES | sort > /packages.txt
 ENV FEATURES clang pyyaml sdl2
-- 
2.20.1