create-mksspec.sh: Add support for OS-cascade

Signed-off-by: Jan Lindemann <jan@janware.com>

scripts/create-mkspec.sh

@@ -39,6 +39,18 @@ subpackage_description()
 	esac
 }
 
+os_cascade()
+{
+	# might want to run python3 path/to/projects.py --os=suse-tumbleweed os-cascade
+	# or turn this into a python script and use projects.py as a module.
+
+	if [ "$DISTRIBUTION" ]; then
+		echo os linux $DISTRIBUTION | sed 's/\([^-]\+\)-\([^-]\+\)/\1 \1-\2/g'
+	else
+		echo os linux
+	fi
+}
+
 # -- here we go
 
 echo "== running $0" "$@" >&2
@@ -123,16 +135,29 @@ for p in $subpackages; do
 
 	for stage in pre preun post postun; do
 		echo "== processing stage $stage: cfg_section pkg.$p.$stage" >&2
-		cfg_section pkg.$p.$stage >&2
-		cfg_section pkg.$p.$stage | grep -q . && {
+		out=""
+		#for os in '' `os_cascade | sed 's/\(^\| \)/ ./g'`; do
+		for os in '' `os_cascade`; do
+			sec=pkg.$p.$stage
+			if [ "$os" ]; then
+				sec="$sec.$os"
+				head="\n# --- $os\n"
+			else
+				head=""
+			fi
+			cfg_section $sec | grep -q . || continue
+			out="$out$head`cfg_section $sec`"
+		done
+		if [ "$out" ]; then
+			echo -e "$out" >&2
 			_cat <<- EOT
 			|echo ""
 			|echo "%$stage -n \$NAME-$p"
 			EOT
 			echo "cat << EOT"
-			cfg_section pkg.$p.$stage | cfg_escape
+			echo -e "$out" | cfg_escape
 			echo "EOT"
-		}
+		fi
 	done
 
 	_cat <<- EOT