lint: catch missing --rm flag for 'docker run'

Not having the --rm flag causes docker containers to be stored forever,
so make sure we always add it to the "docker run" commands that we run
on jenkins via scripts in various repositories.

Depends: docker-playground I48b01c43fedf379b8a565eaab0369806d7831bd8
Related: https://osmocom.org/projects/osmocom-servers/wiki/Docker_cache_clean_up
Related: SYS#5827, OS#5099
Change-Id: I8ab9c291504475d670bdefc50c4524c5bdd4c880

lint/docker_run_rm.sh

@@ -0,0 +1,17 @@
+#!/bin/sh
+# Verify that "docker run" has a "--rm" in the same line or next line, so we
+# don't fill up space on jenkins nodes with never deleted containers:
+# https://osmocom.org/projects/osmocom-servers/wiki/Docker_cache_clean_up
+
+RET=0
+
+for i in $(git grep -l '^[^#]*docker run'); do
+	if [ -z "$(grep -A1 "docker run" "$i" | grep -- "--rm")" ]; then
+		echo "ERROR: missing --rm after 'docker run' (same line or next line):"
+		grep --color=always -H -n -A1 "docker run" "$i"
+		echo
+		RET=1
+	fi
+done
+
+exit $RET

lint/lint_diff.sh

@@ -19,20 +19,31 @@ if [ -z "$COMMIT" ]; then
 	fi
 fi
 
+ERROR=0
+
+echo "Running docker_run_rm.sh on the whole tree..."
+echo
+if ! "$SCRIPT_DIR"/docker_run_rm.sh; then
+	ERROR=1
+fi
+
 echo "Running checkpatch on 'git diff $COMMIT'..."
 echo
-if git diff -U0 "$COMMIT" | "$SCRIPT_DIR/checkpatch/checkpatch_osmo.sh" - \
+if ! git diff -U0 "$COMMIT" | "$SCRIPT_DIR/checkpatch/checkpatch_osmo.sh" - \
 	--color=always \
 	--mailback \
 	--show-types \
 	--showfile \
 	--terse
 then
-	exit 0
+	ERROR=1
 fi
 
-echo
-echo "Please fix the linting errors above. More information:"
-echo "https://osmocom.org/projects/cellular-infrastructure/wiki/Linting"
-echo
-exit 1
+
+if [ "$ERROR" = 1 ]; then
+	echo
+	echo "Please fix the linting errors above. More information:"
+	echo "https://osmocom.org/projects/cellular-infrastructure/wiki/Linting"
+	echo
+	exit 1
+fi