Split grokPacket into inbound/outbound versions.

1 files changed, 19 insertions, 10 deletions

diff --git a/src/Data/PacketBuffer.hs b/src/Data/PacketBuffer.hs
index c5ede50d..f01abb28 100644
--- a/src/Data/PacketBuffer.hs
+++ b/src/Data/PacketBuffer.hs
@@ -1,9 +1,12 @@
 {-# LANGUAGE TupleSections #-}
+{-# LANGUAGE DeriveFunctor #-}
 module Data.PacketBuffer
     ( PacketBuffer
     , newPacketBuffer
-    , PacketEvent(..)
-    , grokPacket
+    , PacketOutboundEvent(..)
+    , PacketInboundEvent(..)
+    , grokOutboundPacket
+    , grokInboundPacket
     , awaitReadyPacket
     , packetNumbersToRequest
     , expectingSequenceNumber
@@ -32,17 +35,21 @@ newPacketBuffer = PacketBuffer <$> Q.new 200 0
                                <*> Q.new 400 0
 
 -- | Input for 'grokPacket'.
-data PacketEvent a b
-    = PacketSent { peSeqNum      :: Word32 -- ^ Sequence number for payload.
-                 , peSentPayload :: b      -- ^ Payload packet we sent to them.
+data PacketOutboundEvent b
+    = PacketSent { poSeqNum      :: Word32 -- ^ Sequence number for payload.
+                 , poSentPayload :: b      -- ^ Payload packet we sent to them.
                  }
-    | PacketReceived { peSeqNum          :: Word32 -- ^ Sequence number for payload.
+ deriving Functor
+
+data PacketInboundEvent a
+    = PacketReceived { peSeqNum          :: Word32 -- ^ Sequence number for payload.
                      , peReceivedPayload :: a      -- ^ Payload packet they sent to us.
                      , peAcknowledgedNum :: Word32 -- ^ Earliest sequence number they've seen from us.
                      }
     | PacketReceivedLossy { peSeqNum          :: Word32 -- ^ Sequence number for lossy packet.
                           , peAcknowledgedNum :: Word32 -- ^ Earliest sequence number they've seen from us.
                           }
+ deriving Functor
 
 -- | Whenever a packet is received or sent (but not resent) from the network,
 -- this function should be called to update the relevant buffers.
@@ -50,14 +57,16 @@ data PacketEvent a b
 -- On outgoing packets, if the outbound buffer is full, this will block
 -- indefinitely until it is called in another thread with an inbound
 -- acknowledgement.
-grokPacket :: PacketBuffer a b -> PacketEvent a b -> STM ()
-grokPacket (PacketBuffer _   outb) (PacketSent seqno a)
+grokOutboundPacket :: PacketBuffer a b -> PacketOutboundEvent b -> STM ()
+grokOutboundPacket (PacketBuffer _   outb) (PacketSent seqno a)
     = do (n,_) <- Q.enqueue outb seqno a
          when (n/=0) retry
-grokPacket (PacketBuffer inb outb) (PacketReceived seqno a ack)
+
+grokInboundPacket :: PacketBuffer a b -> PacketInboundEvent a -> STM ()
+grokInboundPacket (PacketBuffer inb outb) (PacketReceived seqno a ack)
     = do Q.enqueue inb seqno a
          Q.dropPacketsBefore outb ack
-grokPacket (PacketBuffer inb outb) (PacketReceivedLossy seqno ack)
+grokInboundPacket (PacketBuffer inb outb) (PacketReceivedLossy seqno ack)
     = do Q.observeOutOfBand inb seqno
          Q.dropPacketsBefore outb ack