tests: add a simple test for the mountinfo parsing logic

src/test/meson.build

@@ -652,6 +652,14 @@ tests += [
          [],
          [libdl],
          '', 'manual'],
+
+        [['src/test/test-umount.c',
+          'src/core/mount-setup.c',
+          'src/core/mount-setup.h',
+          'src/core/umount.c',
+          'src/core/umount.h'],
+         [],
+         [libmount]],
 ]
 
 ############################################################

src/test/test-umount.c

@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include "log.h"
+#include "string-util.h"
+#include "tests.h"
+#include "umount.h"
+#include "util.h"
+
+static void test_mount_points_list(const char *fname) {
+        LIST_HEAD(MountPoint, mp_list_head);
+        MountPoint *m;
+
+        log_info("/* %s(\"%s\") */", __func__, fname ?: "/proc/self/mountinfo");
+
+        LIST_HEAD_INIT(mp_list_head);
+        assert_se(mount_points_list_get(fname, &mp_list_head) >= 0);
+
+        LIST_FOREACH(mount_point, m, mp_list_head)
+                log_debug("path=%s o=%s f=0x%lx try-ro=%s dev=%u:%u",
+                          m->path,
+                          strempty(m->remount_options),
+                          m->remount_flags,
+                          yes_no(m->try_remount_ro),
+                          major(m->devnum), minor(m->devnum));
+
+        mount_points_list_free(&mp_list_head);
+}
+
+int main(int argc, char **argv) {
+        log_set_max_level(LOG_DEBUG);
+        log_parse_environment();
+        log_open();
+
+        test_mount_points_list(NULL);
+        test_mount_points_list(get_testdata_dir("/test-umount/empty.mountinfo"));
+        test_mount_points_list(get_testdata_dir("/test-umount/garbled.mountinfo"));
+        test_mount_points_list(get_testdata_dir("/test-umount/rhbug-1554943.mountinfo"));
+}