From bedd14d2ea48d753309bd55726fac5c4a9339e5f Mon Sep 17 00:00:00 2001
From: Holger Vogt <holger.vogt@uni-due.de>
Date: Mon, 12 May 2025 23:34:02 +0200
Subject: [PATCH] Add a breakpoint when command 'stop' is used after tran
 simulation has already started

---
 src/frontend/breakp.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/src/frontend/breakp.c b/src/frontend/breakp.c
index 83eab7771..c1fa63785 100644
--- a/src/frontend/breakp.c
+++ b/src/frontend/breakp.c
@@ -12,6 +12,7 @@ Author: 1985 Wayne A. Christopher, U. C. Berkeley CAD Group
 #include "ngspice/ftedefs.h"
 #include "ngspice/dvec.h"
 #include "ngspice/ftedebug.h"
+#include "ngspice/cktdefs.h"
 #include "breakp.h"
 #include "breakp2.h"
 #include "runcoms2.h"
@@ -186,6 +187,19 @@ com_stop(wordlist *wl)
         (void) sprintf(buf, "%d", debugnumber);
         cp_addkword(CT_DBNUMS, buf);
         debugnumber++;
+        /* If com_stop is called after tran simulation has already started, set a breakpoint
+           if not in the past */
+        if ((thisone->db_type == DB_STOPWHEN) && cieq(thisone->db_nodename1, "time")) {
+            if (thisone->db_value2 > ft_curckt->ci_ckt->CKTtime) {
+                CKTsetBreak(ft_curckt->ci_ckt, thisone->db_value2);
+                if (ft_ngdebug)
+                    printf("breakpoint set to time = %g\n", thisone->db_value2);
+            }
+            else {
+                fprintf(stderr, "\nWarning: command 'stop' would set breakpoint in the past, ignored!\n"
+                "    time: %g, bkpt: %e\n\n", ft_curckt->ci_ckt->CKTtime, thisone->db_value2);
+            }
+        }
     }
 
     return;