use race instead of or to avoid lockup (#1042)

Author: etan-status

libp2p/muxers/yamux/yamux.nim

@@ -266,7 +266,9 @@ method readOnce*(
     raise newLPStreamRemoteClosedError()
   if channel.recvQueue.len == 0:
     channel.receivedData.clear()
-    await channel.closedRemotely or channel.receivedData.wait()
+    try:  # https://github.com/status-im/nim-chronos/issues/516
+      discard await race(channel.closedRemotely, channel.receivedData.wait())
+    except ValueError: raiseAssert("Futures list is not empty")
     if channel.closedRemotely.done() and channel.recvQueue.len == 0:
       channel.returnedEof = true
       channel.isEof = true

libp2p/protocols/connectivity/relay/utils.nim

@@ -55,7 +55,9 @@ proc bridge*(connSrc: Connection, connDst: Connection) {.async.} =
 
   try:
     while not connSrc.closed() and not connDst.closed():
-      await futSrc or futDst
+      try:  # https://github.com/status-im/nim-chronos/issues/516
+        discard await race(futSrc, futDst)
+      except ValueError: raiseAssert("Futures list is not empty")
       if futSrc.finished():
         bufRead = await futSrc
         if bufRead > 0:

libp2p/protocols/secure/secure.nim

@@ -97,7 +97,10 @@ proc handleConn(s: Secure,
         let
           fut1 = conn.join()
           fut2 = sconn.join()
-        await fut1 or fut2  # one join() completes, cancel outstanding join()
+        try:  # https://github.com/status-im/nim-chronos/issues/516
+          discard await race(fut1, fut2)
+        except ValueError: raiseAssert("Futures list is not empty")
+        # at least one join() completed, cancel pending one, if any
         if not fut1.finished: await fut1.cancelAndWait()
         if not fut2.finished: await fut2.cancelAndWait()
       block:

libp2p/transports/tcptransport.nim

@@ -68,7 +68,10 @@ proc connHandler*(self: TcpTransport,
         let
           fut1 = client.join()
           fut2 = conn.join()
-        await fut1 or fut2  # one join() completes, cancel outstanding join()
+        try:  # https://github.com/status-im/nim-chronos/issues/516
+          discard await race(fut1, fut2)
+        except ValueError: raiseAssert("Futures list is not empty")
+        # at least one join() completed, cancel pending one, if any
         if not fut1.finished: await fut1.cancelAndWait()
         if not fut2.finished: await fut2.cancelAndWait()