tcp_in-c.patch

--- lib/lwip/src/core/tcp_in.c.orig	2022-09-06 08:57:44.567338501 +0200
+++ lib/lwip/src/core/tcp_in.c	2022-09-06 09:02:40.852363365 +0200
@@ -85,6 +85,8 @@
 static u8_t recv_flags;
 static struct pbuf *recv_data;
 
+int outOfPcb;
+
 struct tcp_pcb *tcp_input_pcb;
 
 /* Forward declarations. */
@@ -662,12 +664,13 @@
        SYN at a time when we have more memory available. */
     if (npcb == NULL) {
       err_t err;
+      outOfPcb++;
       LWIP_DEBUGF(TCP_DEBUG, ("tcp_listen_input: could not allocate PCB\n"));
       TCP_STATS_INC(tcp.memerr);
       TCP_EVENT_ACCEPT(pcb, NULL, pcb->callback_arg, ERR_MEM, err);
       LWIP_UNUSED_ARG(err); /* err not useful here */
       return;
-    }
+    } else if (outOfPcb > 0) { outOfPcb--; printf("\noutOfPcb restored = %d\n", outOfPcb); }
 #if TCP_LISTEN_BACKLOG
     pcb->accepts_pending++;
     tcp_set_flags(npcb, TF_BACKLOGPEND);