Remove dependence on bsd-sysctl package

… since it doesn't work on Linux

darwin/Sysctl.hs

@@ -1,4 +0,0 @@
-module Sysctl where
-
-_SO_MAX_CONN :: String
-_SO_MAX_CONN = "kern.ipc.somaxconn"

linux/Sysctl.hs

@@ -1,4 +0,0 @@
-module Sysctl where
-
-_SO_MAX_CONN :: String
-_SO_MAX_CONN = "net.core.somaxconn"

nix-serve-ng.cabal

@@ -15,17 +15,9 @@ executable nix-serve-ng
 
     main-is:          Main.hs
 
-    other-modules:    Sysctl
+    other-modules:    Nix
-                    , Nix
                     , Options
 
-    if os(darwin)
-      hs-source-dirs: darwin
-    elif os(linux)
-      hs-source-dirs: linux
-    else
-      buildable:      False
-
     -- https://nixos.org/manual/nix/stable/installation/supported-platforms.html
     if arch(i686) && os(linux)
       cxx-options:    -DSYSTEM="i686-linux"
@@ -49,7 +41,6 @@ executable nix-serve-ng
     build-depends:    base < 5
                     , base16
                     , base32
-                    , bsd-sysctl
                     , bytestring
                     , charset
                     , http-types

nix/nix-serve-ng.nix

@@ -1,7 +1,7 @@
-{ mkDerivation, base, base16, base32, bsd-sysctl, bytestring
+{ mkDerivation, base, base16, base32, bytestring, charset
-, charset, http-types, lib, managed, megaparsec, mtl, network
+, http-types, lib, managed, megaparsec, mtl, network, nixstore
-, nixstore, nixutil, optparse-applicative, vector, wai, wai-extra
+, nixutil, optparse-applicative, vector, wai, wai-extra, warp
-, warp, warp-tls
+, warp-tls
 }:
 mkDerivation {
   pname = "nix-serve-ng";
@@ -10,9 +10,8 @@ mkDerivation {
   isLibrary = false;
   isExecutable = true;
   executableHaskellDepends = [
-    base base16 base32 bsd-sysctl bytestring charset http-types managed
+    base base16 base32 bytestring charset http-types managed megaparsec
-    megaparsec mtl network optparse-applicative vector wai wai-extra
+    mtl network optparse-applicative vector wai wai-extra warp warp-tls
-    warp warp-tls
   ];
   executableSystemDepends = [ nixstore nixutil ];
   description = "A drop-in replacement for nix-serve that's faster and more stable";

src/Main.hs

@@ -13,8 +13,8 @@ import Data.Function ((&))
 import Network.Socket (SockAddr(..))
 import Network.Wai (Application)
 import Nix (PathInfo(..))
+import Numeric.Natural (Natural)
 import Options (Options(..), Socket(..), SSL(..), Verbosity(..))
-import Sysctl (_SO_MAX_CONN)
 
 import qualified Control.Monad                        as Monad
 import qualified Control.Monad.Except                 as Except
@@ -34,7 +34,6 @@ import qualified Network.Wai.Middleware.RequestLogger as RequestLogger
 import qualified Nix
 import qualified Options
 import qualified Options.Applicative                  as Options
-import qualified System.BSD.Sysctl                    as Sysctl
 import qualified System.Environment                   as Environment
 
 data ApplicationOptions = ApplicationOptions
@@ -330,8 +329,8 @@ makeApplication ApplicationOptions{..} request respond = do
         Left response -> respond response
         Right void    -> Void.absurd void
 
-toSocket :: FilePath -> IO Socket.Socket
+toSocket :: Natural -> FilePath -> IO Socket.Socket
-toSocket path = do
+toSocket backlog path = do
     let family = Socket.AF_UNIX
 
     Monad.unless (Socket.isSupportedFamily family) do
@@ -341,8 +340,6 @@ toSocket path = do
 
     Socket.bind socket (SockAddrUnix path)
 
-    backlog <- Sysctl.sysctlReadInt _SO_MAX_CONN
-
     Socket.listen socket (fromIntegral backlog)
 
     return socket
@@ -378,10 +375,10 @@ main = do
 
             Warp.runSettings settings application
 
-        Options{ ssl = Disabled, socket = Unix{ path } } -> do
+        Options{ ssl = Disabled, socket = Unix{ backlog, path } } -> do
             let settings = Warp.defaultSettings
 
-            socket <- toSocket path
+            socket <- toSocket backlog path
 
             Warp.runSettingsSocket settings socket application
 
@@ -395,11 +392,11 @@ main = do
 
             WarpTLS.runTLS tlsSettings settings application
 
-        Options{ ssl = Enabled{ cert, key }, socket = Unix{ path } } -> do
+        Options{ ssl = Enabled{ cert, key }, socket = Unix{ backlog, path } } -> do
             let tlsSettings = WarpTLS.tlsSettings cert key
 
             let settings = Warp.defaultSettings
 
-            socket <- toSocket path
+            socket <- toSocket backlog path
 
             WarpTLS.runTLSSocket tlsSettings settings socket application

src/Options.hs

@@ -9,6 +9,7 @@ import Control.Applicative (optional, (<|>))
 import Data.String (IsString(..))
 import Data.Void (Void)
 import Network.Wai.Handler.Warp (HostPreference, Port)
+import Numeric.Natural (Natural)
 import Options.Applicative (Parser, ParserInfo, ReadM)
 import Text.Megaparsec (Parsec)
 
@@ -18,7 +19,7 @@ import qualified Text.Megaparsec.Char.Lexer as Lexer
 
 data Socket
     = TCP { host :: HostPreference, port :: Port }
-    | Unix { path :: FilePath }
+    | Unix { backlog :: Natural, path :: FilePath }
 
 data SSL = Disabled | Enabled { cert :: FilePath, key :: FilePath }
 
@@ -94,8 +95,18 @@ parseTcp = do
 
     return TCP{..}
 
+defaultBacklog :: Natural
+defaultBacklog = 1024
+
 parseUnix :: Parser Socket
 parseUnix = do
+    backlog <- Options.option Options.auto
+        (   Options.long "backlog"
+        <>  Options.help "The maximum number of connections allowed for the backlog"
+        <>  Options.metavar "INTEGER"
+        <>  Options.value defaultBacklog
+        )
+
     path <- Options.strOption
         (   Options.long "socket"
         <>  Options.short 'S'
@@ -167,7 +178,10 @@ parseListen = do
 
     let parseUnixListen :: Parsec Void String Socket
         parseUnixListen = do
+            let backlog = defaultBacklog
+
             path <- Megaparsec.takeRest
+
             return Unix{..}
 
     let parseSocketListen = parseTcpListen <|> parseUnixListen