From 61b299e411ad862bf8ef04fe56c0871c8aa7d903 Mon Sep 17 00:00:00 2001
From: Etan Kissling <etan@status.im>
Date: Thu, 7 Mar 2024 10:45:25 +0100
Subject: [PATCH] `{.async: (raises).}` for `relay/utils.nim` (#1058)

---
 libp2p/protocols/connectivity/relay/utils.nim | 58 +++++++++++--------
 1 file changed, 35 insertions(+), 23 deletions(-)

diff --git a/libp2p/protocols/connectivity/relay/utils.nim b/libp2p/protocols/connectivity/relay/utils.nim
index ac1965921..46ba9cf79 100644
--- a/libp2p/protocols/connectivity/relay/utils.nim
+++ b/libp2p/protocols/connectivity/relay/utils.nim
@@ -1,5 +1,5 @@
 # Nim-LibP2P
-# Copyright (c) 2023 Status Research & Development GmbH
+# Copyright (c) 2023-2024 Status Research & Development GmbH
 # Licensed under either of
 #  * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE))
 #  * MIT license ([LICENSE-MIT](LICENSE-MIT))
@@ -21,36 +21,48 @@ const
   RelayV2HopCodec* = "/libp2p/circuit/relay/0.2.0/hop"
   RelayV2StopCodec* = "/libp2p/circuit/relay/0.2.0/stop"
 
-proc sendStatus*(conn: Connection, code: StatusV1) {.async.} =
+proc sendStatus*(
+    conn: Connection,
+    code: StatusV1
+) {.async: (raises: [CancelledError, LPStreamError], raw: true).} =
   trace "send relay/v1 status", status = $code & "(" & $ord(code) & ")"
   let
-    msg = RelayMessage(msgType: Opt.some(RelayType.Status), status: Opt.some(code))
+    msg = RelayMessage(
+      msgType: Opt.some(RelayType.Status), status: Opt.some(code))
     pb = encode(msg)
-  await conn.writeLp(pb.buffer)
+  conn.writeLp(pb.buffer)
 
-proc sendHopStatus*(conn: Connection, code: StatusV2) {.async.} =
+proc sendHopStatus*(
+    conn: Connection,
+    code: StatusV2
+) {.async: (raises: [CancelledError, LPStreamError], raw: true).} =
   trace "send hop relay/v2 status", status = $code & "(" & $ord(code) & ")"
   let
     msg = HopMessage(msgType: HopMessageType.Status, status: Opt.some(code))
     pb = encode(msg)
-  await conn.writeLp(pb.buffer)
+  conn.writeLp(pb.buffer)
 
-proc sendStopStatus*(conn: Connection, code: StatusV2) {.async.} =
+proc sendStopStatus*(
+    conn: Connection,
+    code: StatusV2
+) {.async: (raises: [CancelledError, LPStreamError], raw: true).} =
   trace "send stop relay/v2 status", status = $code & " (" & $ord(code) & ")"
   let
     msg = StopMessage(msgType: StopMessageType.Status, status: Opt.some(code))
     pb = encode(msg)
-  await conn.writeLp(pb.buffer)
+  conn.writeLp(pb.buffer)
 
-proc bridge*(connSrc: Connection, connDst: Connection) {.async.} =
+proc bridge*(
+    connSrc: Connection,
+    connDst: Connection) {.async: (raises: [CancelledError]).} =
   const bufferSize = 4096
   var
     bufSrcToDst: array[bufferSize, byte]
     bufDstToSrc: array[bufferSize, byte]
-    futSrc = connSrc.readOnce(addr bufSrcToDst[0], bufSrcToDst.high + 1)
-    futDst = connDst.readOnce(addr bufDstToSrc[0], bufDstToSrc.high + 1)
-    bytesSendFromSrcToDst = 0
-    bytesSendFromDstToSrc = 0
+    futSrc = connSrc.readOnce(addr bufSrcToDst[0], bufSrcToDst.len)
+    futDst = connDst.readOnce(addr bufDstToSrc[0], bufDstToSrc.len)
+    bytesSentFromSrcToDst = 0
+    bytesSentFromDstToSrc = 0
     bufRead: int
 
   try:
@@ -61,25 +73,25 @@ proc bridge*(connSrc: Connection, connDst: Connection) {.async.} =
       if futSrc.finished():
         bufRead = await futSrc
         if bufRead > 0:
-          bytesSendFromSrcToDst.inc(bufRead)
-          await connDst.write(@bufSrcToDst[0..<bufRead])
-          zeroMem(addr(bufSrcToDst), bufSrcToDst.high + 1)
-        futSrc = connSrc.readOnce(addr bufSrcToDst[0], bufSrcToDst.high + 1)
+          bytesSentFromSrcToDst.inc(bufRead)
+          await connDst.write(@bufSrcToDst[0 ..< bufRead])
+          zeroMem(addr bufSrcToDst[0], bufSrcToDst.len)
+        futSrc = connSrc.readOnce(addr bufSrcToDst[0], bufSrcToDst.len)
       if futDst.finished():
         bufRead = await futDst
         if bufRead > 0:
-          bytesSendFromDstToSrc += bufRead
-          await connSrc.write(bufDstToSrc[0..<bufRead])
-          zeroMem(addr(bufDstToSrc), bufDstToSrc.high + 1)
-        futDst = connDst.readOnce(addr bufDstToSrc[0], bufDstToSrc.high + 1)
+          bytesSentFromDstToSrc += bufRead
+          await connSrc.write(bufDstToSrc[0 ..< bufRead])
+          zeroMem(addr bufDstToSrc[0], bufDstToSrc.len)
+        futDst = connDst.readOnce(addr bufDstToSrc[0], bufDstToSrc.len)
   except CancelledError as exc:
     raise exc
-  except CatchableError as exc:
+  except LPStreamError as exc:
     if connSrc.closed() or connSrc.atEof():
       trace "relay src closed connection", src = connSrc.peerId
     if connDst.closed() or connDst.atEof():
       trace "relay dst closed connection", dst = connDst.peerId
     trace "relay error", exc=exc.msg
-  trace "end relaying", bytesSendFromSrcToDst, bytesSendFromDstToSrc
+  trace "end relaying", bytesSentFromSrcToDst, bytesSentFromDstToSrc
   await futSrc.cancelAndWait()
   await futDst.cancelAndWait()