VirtualBox: trying with sudo

.travis.yml

@@ -1,5 +1,4 @@
 language: c
-sudo: false
 addons:
   apt:
     packages:
@@ -7,7 +6,7 @@ addons:
       - qemu
       - qemu-system-x86
       - qemu-system-arm
-      - virtualbox
+      #- virtualbox
       - bochs-sdl
       - sikuli-ide
       # Missing dependencies for sikuli-ide
@@ -23,19 +22,30 @@ addons:
       # example-os build dependencies:
       - nasm
 
+matrix:
+  include:
+    - env: MODE=qemu-system-i386
+      sudo: false
+    - env: MODE=qemu-system-arm
+      sudo: false
+    - env: MODE=virtualbox
+      sudo: true
+    - env: MODE=bochs
+      sudo: false
+
 install:
   # The sikuli-ide packaged with ubuntu 16.04 does not seem to work correctly: missing dependencies, some dependencies are too recent, …
   - mkdir ~/sikulix/
   - wget https://launchpadlibrarian.net/359997648/sikulixsetup-1.1.2.jar -O ~/sikulix/sikulixsetup-1.1.2.jar
   - (cd ~/sikulix && java -jar sikulixsetup-1.1.2.jar options 1 1.1)
   - export PATH="$HOME/sikulix/:$PATH"
-
-env:
-  - MODE=qemu-system-i386
-  - MODE=qemu-system-arm
-  - MODE=virtualbox
-  - MODE=bochs
+  - |
+    if test "$MODE" = virtualbox; then
+      echo "deb https://download.virtualbox.org/virtualbox/debian $(lsb_release --short --codename) contrib" | sudo tee /etc/apt/sources.list.d/virtualbox.list
+      sudo apt-get update
+      sudo apt-get -y install virtualbox "linux-headers-$(uname -r)"
+    fi
 
 script:
   - (cd example-os && make)
-  - xvfb-run -a ./test/${MODE}.sh
+  - xvfb-run -a ./test/${MODE}.sh