check active close from peer in ngx_http_check_recv_handler()

 If there is no data to receive, we finish the health check before timeout.
 Note that, without this patch, timeout handler will do it for us.

Author: chobits

ngx_http_upstream_check_handler.c

@@ -659,6 +659,12 @@ ngx_http_check_recv_handler(ngx_event_t *event)
     switch (rc) {
 
     case NGX_AGAIN:
+        /* The peer has closed its half side of the connection. */
+        if (size == 0) {
+            ngx_http_check_status_update(peer, 0);
+            break;
+        }
+
         return;
 
     case NGX_ERROR: