From 2e65ddb5449a18602eb81776e87e048adfb5f114 Mon Sep 17 00:00:00 2001
From: Andreas Beckmann <anbe@debian.org>
Date: Wed, 22 Mar 2023 18:16:03 +0100
Subject: [PATCH] dkms_autoinstaller: skip autoinstall if headers are missing

align the behavior with dkms_common.postinst which also skips the build
step if headers are not available

Before this change the following installation order succeeds (while
linux-headers-... is *not* installed) (Debian syntax):
  apt install linux-image-... && apt install ...-dkms
while the opposite order causes a failure:
  apt install ...-dkms && apt install linux-image-...
After this change both ways succeed.
---
 dkms_autoinstaller | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/dkms_autoinstaller b/dkms_autoinstaller
index 8c9450c..1b54c51 100755
--- a/dkms_autoinstaller
+++ b/dkms_autoinstaller
@@ -38,6 +38,27 @@ test -f $exec || exit 0
 
 [ -e /etc/sysconfig/$prog ] && . /etc/sysconfig/$prog
 
+uname_s=$(uname -s)
+
+_get_kernel_dir() {
+    KVER=$1
+    case ${uname_s} in
+	Linux)		DIR="/lib/modules/$KVER/build" ;;
+	GNU/kFreeBSD)	DIR="/usr/src/kfreebsd-headers-$KVER/sys" ;;
+    esac
+    echo $DIR
+}
+
+_check_kernel_dir() {
+    DIR=$(_get_kernel_dir $1)
+    case ${uname_s} in
+	Linux)		test -e $DIR/include ;;
+	GNU/kFreeBSD)	test -e $DIR/kern && test -e $DIR/conf/kmod.mk ;;
+	*)		return 1 ;;
+    esac
+    return $?
+}
+
 case "$1" in
     start)
 		if [ -n "$2" ]; then
@@ -47,6 +68,8 @@ case "$1" in
 		fi
 		if [ -f /etc/dkms/no-autoinstall ]; then
 			log_action_msg "$prog: autoinstall for dkms modules has been disabled"
+		elif ! _check_kernel_dir $kernel; then
+			log_action_msg "$prog: autoinstall for kernel $kernel was skipped since the kernel headers for this kernel do not seem to be installed"
 		else
 			log_daemon_msg "$prog: running auto installation service for kernel $kernel"
 			dkms autoinstall --kernelver $kernel
-- 
2.20.1