libcleaner: fix asymmetry in mount table open/close handling

Although nilfs_cleaner_find_fs() uses endmntent() to close the file
descriptor for "/proc/mounts", its uses fopen() directly to open it
instead of setmntent().  This asymmetry is undesirable because it can
cause unintended problems such as lock inconsistencies.  Therefore,
properly use setmntent().

Signed-off-by: Ryusuke Konishi <[email protected]>

Author: konis

lib/cleaner_ctl.c

@@ -194,7 +194,7 @@ static int nilfs_cleaner_find_fs(struct nilfs_cleaner *cleaner,
 		cleaner->mountdir = cdir;
 	}
 
-	fp = fopen(_PATH_MOUNTED, "r");
+	fp = setmntent(_PATH_MOUNTED, "r");
 	if (unlikely(fp == NULL)) {
 		nilfs_cleaner_logger(LOG_ERR, _("Error: cannot open "
 						_PATH_MOUNTED "."));