From c8174b14e1b5430df4631ecaab6b0f77f282d888 Mon Sep 17 00:00:00 2001
From: Florian Forster <octo@leeloo.lan.home.verplant.org>
Date: Sun, 15 Mar 2009 11:47:43 +0100
Subject: [PATCH] src/oping.c: Allow setting of the TTL using `-t'.

---
 src/mans/oping.pod | 13 +++++--------
 src/oping.c        | 33 ++++++++++++++++++++++++++++++---
 2 files changed, 35 insertions(+), 11 deletions(-)

diff --git a/src/mans/oping.pod b/src/mans/oping.pod
index c4e3e63..fba2f56 100644
--- a/src/mans/oping.pod
+++ b/src/mans/oping.pod
@@ -36,6 +36,11 @@ Send (and receive) I<count> ICMP packets, then stop and exit.
 Send one ICMP packet (per host) each I<interval> seconds. This can be a
 floating-point number to specify sub-second precision.
 
+=item B<-t> I<ttl>
+
+Set the IP Time to Live to I<ttl>. This must be a number between (and
+including) 1E<nbsp>andE<nbsp>255. If omitted, the value B<64> is used.
+
 =item B<-I> I<address>
 
 Set the source address to use. You B<cannot> pass the interface name, as you
@@ -43,14 +48,6 @@ can with GNU's L<ping(8)>.
 
 =back
 
-=head1 BUGS
-
-=over 4
-
-=item The TTL cannot be set
-
-=back
-
 =head1 SEE ALSO
 
 L<ping(8)>, L<http://www.fping.com/>, L<liboping(3)>
diff --git a/src/oping.c b/src/oping.c
index bc33c27..0f39dc5 100644
--- a/src/oping.c
+++ b/src/oping.c
@@ -74,6 +74,7 @@ static double  opt_interval   = 1.0;
 static int     opt_addrfamily = PING_DEF_AF;
 static char   *opt_srcaddr    = NULL;
 static int     opt_count      = -1;
+static int     opt_send_ttl   = 64;
 
 static void sigint_handler (int signal)
 {
@@ -107,8 +108,16 @@ static void context_destroy (ping_context_t *context)
 
 static void usage_exit (const char *name)
 {
-	fprintf (stderr, "Usage: %s [-46] [-c count] [-i interval] host [host [host ...]]\n",
-			name);
+	int name_length;
+
+	name_length = (int) strlen (name);
+
+	fprintf (stderr, "Usage: %s [-46] [-c count] [-i interval]\n"
+			"%*s[-t ttl] [-I srcaddr]\n"
+			"%*shost [host [host ...]]\n",
+			name,
+			8 + name_length, "",
+			8 + name_length, "");
 	exit (1);
 }
 
@@ -118,7 +127,7 @@ static int read_options (int argc, char **argv)
 
 	while (1)
 	{
-		optchar = getopt (argc, argv, "46c:hi:I:");
+		optchar = getopt (argc, argv, "46c:hi:I:t:");
 
 		if (optchar == -1)
 			break;
@@ -158,6 +167,18 @@ static int read_options (int argc, char **argv)
 				}
 				break;
 
+			case 't':
+			{
+				int new_send_ttl;
+				new_send_ttl = atoi (optarg);
+				if ((new_send_ttl > 0) && (new_send_ttl < 256))
+					opt_send_ttl = new_send_ttl;
+				else
+					fprintf (stderr, "Invalid TTL argument: %s\n",
+							optarg);
+				break;
+			}
+
 			case 'h':
 			default:
 				usage_exit (argv[0]);
@@ -301,6 +322,12 @@ int main (int argc, char **argv)
 		return (1);
 	}
 
+	if (ping_setopt (ping, PING_OPT_TTL, &opt_send_ttl) != 0)
+	{
+		fprintf (stderr, "Setting TTL to %i failed: %s\n",
+				opt_send_ttl, ping_get_error (ping));
+	}
+
 	{
 		double temp_sec;
 		double temp_nsec;
-- 
2.30.2