From f71f131dcc5f2be5a7da508128e432be78f0376f Mon Sep 17 00:00:00 2001
From: Godzil <godzil@godzil.net>
Date: Fri, 20 Sep 2019 16:26:07 +0100
Subject: [PATCH] Add proper report if something is trying to call a non
 initialized interrupt

aka CS=0000h, IP=0000h which is more than likely to crash the whole thing.
---
 oswan/source/nec/nec.cpp | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/oswan/source/nec/nec.cpp b/oswan/source/nec/nec.cpp
index 5a18808..0bdc20f 100644
--- a/oswan/source/nec/nec.cpp
+++ b/oswan/source/nec/nec.cpp
@@ -128,6 +128,14 @@ void nec_int(uint16_t vector)
       I.TF = I.IF = 0;
       dest_off = ReadWord(vector);
       dest_seg = ReadWord(vector+2);
+
+      if ((dest_off == 0) && (dest_seg == 0))
+      {
+         printf("Something wrong with the interrupt, exiting...\n");
+         //dump_memory();
+         return;
+      }
+
       PUSH(I.sregs[CS]);
       PUSH(I.ip);
       I.ip = (WORD)dest_off;
@@ -151,6 +159,14 @@ static void nec_interrupt(uint32_t int_num, /*BOOLEAN*/ int md_flag)
    dest_off = ReadWord((int_num)*4);
    dest_seg = ReadWord((int_num)*4+2);
 
+   if ((dest_off == 0) && (dest_seg == 0))
+   {
+      printf("Something wrong with the interrupt, exiting...\n");
+      //dump_memory();
+      return;
+   }
+
+
    PUSH(I.sregs[CS]);
    PUSH(I.ip);
    I.ip = (WORD)dest_off;