input_thread: use flb_pipe_r in handle_input_event to fix crash on read error

Signed-off-by: zshuang0316 <zshuang0316@163.com>

Author: zshuang0316

src/flb_input_thread.c

@@ -59,9 +59,9 @@ static inline int handle_input_event(flb_pipefd_t fd, struct flb_input_instance
     uint64_t val;
     struct flb_config *config = ins->config;
 
-    bytes = read(fd, &val, sizeof(val));
+    bytes = flb_pipe_r(fd, &val, sizeof(val));
     if (bytes == -1) {
-        flb_errno();
+        flb_pipe_error();
         return -1;
     }