1 files changed, 73 insertions, 0 deletions
diff --git a/src/test/test-cgroup-setup.c b/src/test/test-cgroup-setup.c
new file mode 100644
index 0000000..72726ca
--- /dev/null
+++ b/src/test/test-cgroup-setup.c
@@ -0,0 +1,73 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <unistd.h>
+
+#include "alloc-util.h"
+#include "build.h"
+#include "cgroup-setup.h"
+#include "errno-util.h"
+#include "log.h"
+#include "proc-cmdline.h"
+#include "string-util.h"
+#include "tests.h"
+
+static void test_is_wanted_print(bool header) {
+        _cleanup_free_ char *cmdline = NULL;
+
+        log_info("-- %s --", __func__);
+        assert_se(proc_cmdline(&cmdline) >= 0);
+        log_info("cmdline: %s", cmdline);
+        if (header) {
+                log_info(_CGROUP_HIERARCHY_);
+                (void) system("findmnt -n /sys/fs/cgroup");
+        }
+
+        log_info("is_unified_wanted() → %s", yes_no(cg_is_unified_wanted()));
+        log_info("is_hybrid_wanted() → %s", yes_no(cg_is_hybrid_wanted()));
+        log_info("is_legacy_wanted() → %s", yes_no(cg_is_legacy_wanted()));
+        log_info(" ");
+}
+
+static void test_is_wanted(void) {
+        assert_se(setenv("SYSTEMD_PROC_CMDLINE",
+                         "systemd.unified_cgroup_hierarchy", 1) >= 0);
+        test_is_wanted_print(false);
+
+        assert_se(setenv("SYSTEMD_PROC_CMDLINE",
+                         "systemd.unified_cgroup_hierarchy=0", 1) >= 0);
+        test_is_wanted_print(false);
+
+        assert_se(setenv("SYSTEMD_PROC_CMDLINE",
+                         "systemd.unified_cgroup_hierarchy=0 "
+                         "systemd.legacy_systemd_cgroup_controller", 1) >= 0);
+        test_is_wanted_print(false);
+
+        assert_se(setenv("SYSTEMD_PROC_CMDLINE",
+                         "systemd.unified_cgroup_hierarchy=0 "
+                         "systemd.legacy_systemd_cgroup_controller=0", 1) >= 0);
+        test_is_wanted_print(false);
+
+        /* cgroup_no_v1=all implies unified cgroup hierarchy, unless otherwise
+         * explicitly specified. */
+        assert_se(setenv("SYSTEMD_PROC_CMDLINE",
+                         "cgroup_no_v1=all", 1) >= 0);
+        test_is_wanted_print(false);
+
+        assert_se(setenv("SYSTEMD_PROC_CMDLINE",
+                         "cgroup_no_v1=all "
+                         "systemd.unified_cgroup_hierarchy=0", 1) >= 0);
+        test_is_wanted_print(false);
+}
+
+int main(void) {
+        test_setup_logging(LOG_DEBUG);
+
+        if (access("/proc/cmdline", R_OK) < 0 && ERRNO_IS_PRIVILEGE(errno))
+                return log_tests_skipped("can't read /proc/cmdline");
+
+        test_is_wanted_print(true);
+        test_is_wanted_print(false); /* run twice to test caching */
+        test_is_wanted();
+
+        return 0;
+}