Don't assume that the time stamp of the last frame is the largest time

stamp in the packet; bugs in the OS kernel or the WinPcap driver, or
just forcibly setting the system time backwards, can cause time stamps
in packet traces not to monotonously increase.  That can cause infinite
loops when picking the scale for the graph.

svn path=/trunk/; revision=6800

1 files changed, 10 insertions, 5 deletions

diff --git a/gtk/tcp_graph.c b/gtk/tcp_graph.c
index 4ba48c7198..6af7d280ac 100644
--- a/gtk/tcp_graph.c
+++ b/gtk/tcp_graph.c
@@ -3,7 +3,7 @@
  * By Pavel Mores <pvl@uh.cz>
  * Win32 port:  rwh@unifiedtech.com
  *
- * $Id: tcp_graph.c,v 1.24 2002/11/11 15:39:06 oabad Exp $
+ * $Id: tcp_graph.c,v 1.25 2002/12/18 23:08:20 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -3221,7 +3221,7 @@ static void tseq_stevens_initialize (struct graph *g)
 static void tseq_stevens_get_bounds (struct graph *g)
 {
 	struct segment *tmp, *last, *first;
-	double t0, tmax, y0, ymax;
+	double t, t0, tmax, y0, ymax;
 
 	for (first=g->segments; first->next; first=first->next) {
 		if (compare_headers (g->current, first, COMPARE_CURR_DIR))
@@ -3229,6 +3229,7 @@ static void tseq_stevens_get_bounds (struct graph *g)
 	}
 	last = NULL;
 	ymax = 0;
+	tmax = 0;
 	for (tmp=g->segments; tmp; tmp=tmp->next) {
 		unsigned int highest_byte_num;
 		last = tmp;
@@ -3238,6 +3239,9 @@ static void tseq_stevens_get_bounds (struct graph *g)
 			highest_byte_num = g_ntohl (tmp->tcphdr.ack_seq);
 		if (highest_byte_num > ymax)
 			ymax = highest_byte_num;
+		t = tmp->rel_secs + tmp->rel_usecs / 1000000.0;
+		if (t > tmax)
+			tmax = t;
 	}
 	if (!last) {
 		puts ("tseq_stevens_get_bounds: segment list corrupted!");
@@ -3245,7 +3249,6 @@ static void tseq_stevens_get_bounds (struct graph *g)
 	}
 
 	t0 = g->segments->rel_secs + g->segments->rel_usecs / 1000000.0;
-	tmax = last->rel_secs + last->rel_usecs / 1000000.0;
 	y0 = g_ntohl (first->tcphdr.seq);
 
 	g->bounds.x0 = t0;
@@ -3558,7 +3561,7 @@ static void tput_initialize (struct graph *g)
 	struct segment *tmp, *oldest, *last;
 	int i, sum=0;
 	double dtime, tput, tputmax=0;
-	double t0, tmax, y0, ymax;
+	double t, t0, tmax = 0, y0, ymax;
 
 	debug(DBS_FENTRY) puts ("tput_initialize()");
 
@@ -3577,10 +3580,12 @@ static void tput_initialize (struct graph *g)
 		debug(DBS_TPUT_ELMTS) printf ("tput=%f\n", tput);
 		if (tput > tputmax)
 			tputmax = tput;
+		t = tmp->rel_secs + tmp->rel_usecs / 1000000.0;
+		if (t > tmax)
+			tmax = t;
 	}
 
 	t0 = g->segments->rel_secs + g->segments->rel_usecs / 1000000.0;
-	tmax = last->rel_secs + last->rel_usecs / 1000000.0;
 	y0 = 0;
 	ymax = tputmax;