initd-lint: add linting tool for openrc initd files

check.do

 exec >&2
+echo ">>> Testing apkbuild-lint"
 bats --tap tests/apkbuild-lint.bats
+
+echo ">>> Testing initd-lint"
+bats --tap tests/initd-lint.bats

initd-lint

+#!/bin/sh
+
+
+lint_msg() {
+    local msg="$1" tag="$2" severity="$3"
+
+    printf '%s:[%s]:%s:%s\n' "$severity" "$tag" "$service" "$msg"
+}
+
+scan() {
+	local rx="$1" msg="$2" tag="$3" severity="$4"
+	grep -P -Hn -e "$rx" "$service" |
+		sed "s/^\([^:]*:[^:]*:\)\(.*\)/$severity:[$tag]:\1$msg/"
+}
+
+unexpected_shebang_line() {
+    shebang=$(awk 'NR == 1' "$service")
+
+    if [ "$shebang" != "#!/sbin/openrc-run" ]; then
+        lint_msg "openrc init files should use '#!/sbin/openrc-run' as shebang line" "AL33" "IC"
+    fi
+}
+
+custom_start_stop_function() {
+    scan '(start|stop)\s*\(\)\s*\{' "Don't define a custom start\/stop function" 'AL34' 'IC'
+}
+
+_ret=0
+for service; do
+	if [ ! -f "$service" ]; then
+		echo "error: no such file: '$service'"
+		exit 1
+	fi
+
+	unexpected_shebang_line
+	custom_start_stop_function
+done | sort -t: -V | grep . && _ret=1
+exit $_ret

tests/initd-lint.bats

+#!/usr/bin/env bats
+
+cmd=./initd-lint
+service=$BATS_TMPDIR/service.initd
+
+assert_match() {
+	output=$1
+	expected=$2
+
+	echo "$output" | grep -qE "$expected"
+}
+
+@test 'warn about non-standard shebang' {
+	cat <<-"EOF" >$service
+	#!/bin/sh
+
+	cmd_run="my_service"
+	EOF
+
+	run $cmd $service
+
+	[[ $status -eq 1 ]]
+	assert_match "${lines[0]}" "should use '#!/sbin/openrc-run'"
+}
+
+@test "don't warn about standard shebang" {
+	cat <<-"EOF" >$service
+	#!/sbin/openrc-run
+
+	cmd_run="my_service"
+	EOF
+
+	run $cmd $service
+
+	[[ $status -eq 0 ]]
+}
+
+@test "warn about custom start function" {
+	cat <<-"EOF" >$service
+	#!/sbin/openrc-run
+
+	start() {
+		start_command
+	}
+	EOF
+
+	run $cmd $service
+
+	[[ $status -eq 1 ]]
+	assert_match "${lines[0]}" "custom start/stop function"
+}
+
+@test "warn about custom stop function" {
+	cat <<-"EOF" >$service
+	#!/sbin/openrc-run
+
+	stop () {
+		stop_command
+	}
+	EOF
+
+	run $cmd $service
+
+	[[ $status -eq 1 ]]
+	assert_match "${lines[0]}" "custom start/stop function"
+}