From 86af73454270d30acae193f98fb75bb1b8bee71b Mon Sep 17 00:00:00 2001
From: Milo Turner <iitalics@gmail.com>
Date: Tue, 10 Mar 2020 12:32:23 -0400
Subject: [PATCH] handle duplicate packets

---
 hptp-recv/src/main.rs | 29 ++++++++++++++++++++---------
 hptp/src/logger.rs    | 14 ++++++++++----
 2 files changed, 30 insertions(+), 13 deletions(-)

diff --git a/hptp-recv/src/main.rs b/hptp-recv/src/main.rs
index 54250c4..b29a5a0 100644
--- a/hptp-recv/src/main.rs
+++ b/hptp-recv/src/main.rs
@@ -61,16 +61,27 @@ where
     loop {
         match peer.recv().await {
             Ok(UpMsg::Data { payload, seg_idx }) => {
-                let len = payload.len();
-                segs.entry(seg_idx).or_insert(Some(payload));
-                let ack = DownMsg::Ack {
-                    idxs: segs.keys().cloned().collect(),
-                };
-                log.debug_msg(format!("sent ack: {:?}",
-                                      segs.keys().collect::<Vec<_>>())).await;
-                send(peer, ack).await?;
-                log.recv_data_accepted(seg_idx as usize, len, hptp::logger::OutOfOrder)
+                if segs.contains_key(&seg_idx) {
+                    log.recv_data_ignored(seg_idx as usize, payload.len()).await;
+                } else {
+                    log.recv_data_accepted(
+                        seg_idx as usize,
+                        payload.len(),
+                        hptp::logger::OutOfOrder,
+                    )
                     .await;
+                    segs.insert(seg_idx, Some(payload));
+                    let ack = DownMsg::Ack {
+                        idxs: segs.keys().cloned().collect(),
+                    };
+                    log.debug_msg(format!("sent ack: {:?}", {
+                        let mut idxs = segs.keys().collect::<Vec<_>>();
+                        idxs.sort_unstable();
+                        idxs
+                    }))
+                    .await;
+                    send(peer, ack).await?;
+                }
             }
 
             Err(peer::RecvError::InvalidMessage { .. }) => log.recv_corrupt().await,
diff --git a/hptp/src/logger.rs b/hptp/src/logger.rs
index 2376e81..bf8ec0d 100644
--- a/hptp/src/logger.rs
+++ b/hptp/src/logger.rs
@@ -44,8 +44,9 @@ impl Logger {
             .await
     }
 
-    pub async fn recv_data_ignored(&mut self) {
-        self.log_payload(LogPayload::RecvDataIgnored).await
+    pub async fn recv_data_ignored(&mut self, start: usize, len: usize) {
+        self.log_payload(LogPayload::RecvDataIgnored { start, len })
+            .await
     }
 
     pub async fn recv_ack(&mut self, last_offset: usize) {
@@ -91,7 +92,10 @@ enum LogPayload<'a> {
         len: usize,
         order: AcceptedOrder,
     },
-    RecvDataIgnored,
+    RecvDataIgnored {
+        start: usize,
+        len: usize,
+    },
     RecvAck {
         last_offset: usize,
     },
@@ -134,7 +138,9 @@ impl Display for LogPayload<'_> {
             LogPayload::RecvDataAccepted { start, len, order } => {
                 write!(f, "[recv data] {} ({}) ACCEPTED ({})", start, len, order)
             }
-            LogPayload::RecvDataIgnored => write!(f, "[recv data] IGNORED"),
+            LogPayload::RecvDataIgnored { start, len } => {
+                write!(f, "[recv data] {} ({}) IGNORED", start, len)
+            }
             LogPayload::RecvCorrupt => write!(f, "[recv corrupt packet]"),
             LogPayload::RecvAck { last_offset } => write!(f, "[recv ack] {}", last_offset),
             LogPayload::SendData { start, len } => write!(f, "[send data] {} ({})", start, len),