log entry if dav_lock returns EEXIST

src/cache.c

@@ -931,8 +931,15 @@ dav_create(dav_node **nodep, dav_node *parent, const char *name, uid_t uid,
     (*nodep)->uid = uid;
     (*nodep)->gid = pw->pw_gid;
     int ret = create_cache_file(*nodep);
+
     if (!ret)
         ret = dav_lock(path, &(*nodep)->lock_expire, &(*nodep)->remote_exists);
+    if (ret == EEXIST)
+        syslog(LOG_MAKEPRI(LOG_DAEMON, LOG_ERR),
+               _("The server reports a file that should not exist."
+                 "Maybe it is an error in the servers LOCK impementation."
+                 "You may try option 'use_locks 0' in davfs2.conf."));
+
     if (!ret) {
         (*nodep)->smtime = (*nodep)->mtime;
         if (!is_created(*nodep))