core: tcp keep-alive parameters for windows (#336)

src/Simplex/Messaging/Client.hs

@@ -114,7 +114,7 @@ smpDefaultConfig =
       defaultTransport = ("5223", transport @TLS),
       tcpTimeout = 4_000_000,
       tcpKeepAlive = Just defaultKeepAliveOpts,
-      smpPing = 1_200_000_000 -- 20min
+      smpPing = 600_000_000 -- 10min
     }
 
 data Request = Request

src/Simplex/Messaging/Transport/KeepAlive.hs

@@ -7,19 +7,6 @@ module Simplex.Messaging.Transport.KeepAlive where
 import Foreign.C (CInt (..))
 import Network.Socket
 
-_SOL_TCP :: CInt
-_SOL_TCP = 6
-
-#if defined(darwin_HOST_OS)
-foreign import capi "netinet/tcp.h value TCP_KEEPALIVE" _TCP_KEEPIDLE :: CInt
-#else
-foreign import capi "netinet/tcp.h value TCP_KEEPIDLE" _TCP_KEEPIDLE :: CInt
-#endif
-
-foreign import capi "netinet/tcp.h value TCP_KEEPINTVL" _TCP_KEEPINTVL :: CInt
-
-foreign import capi "netinet/tcp.h value TCP_KEEPCNT" _TCP_KEEPCNT :: CInt
-
 data KeepAliveOpts = KeepAliveOpts
   { keepIdle :: Int,
     keepIntvl :: Int,
@@ -34,6 +21,39 @@ defaultKeepAliveOpts =
       keepCnt = 4
     }
 
+_SOL_TCP :: CInt
+_SOL_TCP = 6
+
+#if defined(mingw32_HOST_OS)
+-- Windows
+
+-- The values are copied from windows::Win32::Networking::WinSock
+-- https://microsoft.github.io/windows-docs-rs/doc/windows/Win32/Networking/WinSock/index.html
+
+_TCP_KEEPIDLE :: CInt
+_TCP_KEEPIDLE = 3
+
+_TCP_KEEPINTVL :: CInt
+_TCP_KEEPINTVL = 17
+
+_TCP_KEEPCNT :: CInt
+_TCP_KEEPCNT = 16
+
+#else
+-- Mac/Linux
+
+#if defined(darwin_HOST_OS)
+foreign import capi "netinet/tcp.h value TCP_KEEPALIVE" _TCP_KEEPIDLE :: CInt
+#else
+foreign import capi "netinet/tcp.h value TCP_KEEPIDLE" _TCP_KEEPIDLE :: CInt
+#endif
+
+foreign import capi "netinet/tcp.h value TCP_KEEPINTVL" _TCP_KEEPINTVL :: CInt
+
+foreign import capi "netinet/tcp.h value TCP_KEEPCNT" _TCP_KEEPCNT :: CInt
+
+#endif 
+
 setSocketKeepAlive :: Socket -> KeepAliveOpts -> IO ()
 setSocketKeepAlive sock KeepAliveOpts {keepCnt, keepIdle, keepIntvl} = do
   setSocketOption sock KeepAlive 1