From dcf41cfe8154d7b3948d251d5f9394af46b2084c Mon Sep 17 00:00:00 2001
From: Alex Burka <aburka@exyntechnologies.com>
Date: Wed, 10 Apr 2024 20:19:51 +0000
Subject: [PATCH] docker: fix docker detection in install-prereqs-ubuntu.sh

The standard "are we in docker" checks don't seem to work during a
build, so just use an environment variable.
---
 Dockerfile                                          | 1 +
 Tools/environment_install/install-prereqs-ubuntu.sh | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/Dockerfile b/Dockerfile
index 6eb16c75cb..22d8d67292 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -35,6 +35,7 @@ USER ${USER_NAME}
 
 RUN SKIP_AP_EXT_ENV=$SKIP_AP_EXT_ENV SKIP_AP_GRAPHIC_ENV=$SKIP_AP_GRAPHIC_ENV SKIP_AP_COV_ENV=$SKIP_AP_COV_ENV SKIP_AP_GIT_CHECK=$SKIP_AP_GIT_CHECK \
     DO_AP_STM_ENV=$DO_AP_STM_ENV \
+    AP_DOCKER_BUILD=1 \
     USER=${USER_NAME} \
     Tools/environment_install/install-prereqs-ubuntu.sh -y
 
diff --git a/Tools/environment_install/install-prereqs-ubuntu.sh b/Tools/environment_install/install-prereqs-ubuntu.sh
index 2ceb176813..0aea76a53b 100755
--- a/Tools/environment_install/install-prereqs-ubuntu.sh
+++ b/Tools/environment_install/install-prereqs-ubuntu.sh
@@ -357,7 +357,7 @@ $APT_GET install $BASE_PKGS $SITL_PKGS $PX4_PKGS $ARM_LINUX_PKGS $COVERAGE_PKGS
 
 heading "Check if we are inside docker environment..."
 IS_DOCKER=false
-if [[ -f /.dockerenv ]] || grep -Eq '(lxc|docker)' /proc/1/cgroup ; then
+if [[ ${AP_DOCKER_BUILD:-0} -eq 1 ]] || [[ -f /.dockerenv ]] || grep -Eq '(lxc|docker)' /proc/1/cgroup ; then
     IS_DOCKER=true
 fi
 echo "Done!"