Bug appneta#210 avoid overflow with -M option

src/defines.h.in

@@ -83,6 +83,7 @@
 #define COUNTER unsigned long
 #define COUNTER_SPEC "%lu"
 #endif
+#define COUNTER_OVERFLOW_RISK (((COUNTER)~0) >> 20)
 
 #include "common/list.h"
 #include "common/cidr.h"

src/send_packets.c

@@ -1155,11 +1155,19 @@ static bool calc_sleep_time(tcpreplay_t *ctx, struct timeval *pkt_time_delta,
          */
         now_us = TIMSTAMP_TO_MICROSEC(sent_timestamp);
         if (now_us) {
+            COUNTER next_tx_us;
             COUNTER bps = options->speed.speed;
             COUNTER bits_sent = ((ctx->stats.bytes_sent + len) * 8);
-            /* bits * 1000000 divided by bps = microseconds */
-            COUNTER next_tx_us = (bits_sent * 1000000) / bps;
             COUNTER tx_us = now_us - *start_us;
+            /*
+             * bits * 1000000 divided by bps = microseconds
+             *
+             * ensure there is no overflow in cases where bits_sent is very high
+             */
+            if (bits_sent > COUNTER_OVERFLOW_RISK && bps > 500000)
+                next_tx_us = (bits_sent * 1000) / bps * 1000;
+            else
+                next_tx_us = (bits_sent * 1000000) / bps;
             if (next_tx_us > tx_us) {
                 NANOSEC_TO_TIMESPEC((next_tx_us - tx_us) * 1000, &ctx->nap);
             } else if (tx_us > next_tx_us) {

src/tcprewrite.c

@@ -236,9 +236,6 @@ rewrite_packets(tcpedit_t *tcpedit, pcap_t *pin, pcap_dumper_t *pout)
     int rcode;
 #ifdef ENABLE_FRAGROUTE
     int frag_len, proto;
-#ifdef DEBUG
-    int i;
-#endif
 #endif
 
     pkthdr_ptr = &pkthdr;