Add support for windowsize option (RFC 7440)

Author: lazy404

README.md

@@ -13,6 +13,7 @@ The following RFCs are implemented:
 * [RFC 2347] - TFTP Option Extension.
 * [RFC 2348] - TFTP Blocksize Option.
 * [RFC 2349] - TFTP Timeout Interval and Transfer Size Options.
+* [RFC 7440] - TFTP Windowsize Option.
 
 Features:
 

examples/tftpd-dir.rs

@@ -14,6 +14,7 @@ async fn main() -> Result<()> {
         .bind("0.0.0.0:6969".parse().unwrap())
         // Workaround to handle cases where client is behind VPN
         .block_size_limit(1024)
+        .window_size(64)
         .build()
         .await?;