From de54e5484af00b23ade92d685debfdf205dd66b7 Mon Sep 17 00:00:00 2001
From: monacoremo <59358383+monacoremo@users.noreply.github.com>
Date: Sat, 24 Apr 2021 16:06:10 +0200
Subject: [PATCH] fix: Panic when attempting to run with unix socket on
 non-unix host

---
 main/Main.hs          |  6 +++---
 src/PostgREST/App.hs  | 12 ++++++++----
 src/PostgREST/CLI.hs  |  6 +++---
 src/PostgREST/Unix.hs |  6 +++---
 4 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/main/Main.hs b/main/Main.hs
index c5e73bab16..15abf009c1 100644
--- a/main/Main.hs
+++ b/main/Main.hs
@@ -31,11 +31,11 @@ installSignalHandlers = Unix.installSignalHandlers
 installSignalHandlers _ = pass
 #endif
 
-runAppInSocket :: App.SocketRunner
+runAppInSocket :: Maybe App.SocketRunner
 #ifndef mingw32_HOST_OS
-runAppInSocket = Unix.runAppInSocket
+runAppInSocket = Just Unix.runAppWithSocket
 #else
-runAppInSocket _ _ _ _ = pass
+runAppInSocket = Nothing
 #endif
 
 setBuffering :: IO ()
diff --git a/src/PostgREST/App.hs b/src/PostgREST/App.hs
index 1066461c84..0e369d1681 100644
--- a/src/PostgREST/App.hs
+++ b/src/PostgREST/App.hs
@@ -101,8 +101,8 @@ type SignalHandlerInstaller = AppState -> IO()
 type SocketRunner = Warp.Settings -> Wai.Application -> FileMode -> FilePath -> IO()
 
 
-run :: SignalHandlerInstaller -> SocketRunner -> AppState -> IO ()
-run installHandlers runInSocket appState = do
+run :: SignalHandlerInstaller -> Maybe SocketRunner -> AppState -> IO ()
+run installHandlers maybeRunWithSocket appState = do
   conf@AppConfig{..} <- AppState.getConfig appState
   connectionWorker appState -- Loads the initial DbStructure
   installHandlers appState
@@ -113,8 +113,12 @@ run installHandlers runInSocket appState = do
 
   case configServerUnixSocket of
     Just socket ->
-      -- run the postgrest application with user defined socket. Only for UNIX systems.
-      runInSocket (serverSettings conf) app configServerUnixSocketMode socket
+      -- run the postgrest application with user defined socket. Only for UNIX systems
+      case maybeRunWithSocket of
+        Just runWithSocket ->
+          runWithSocket (serverSettings conf) app configServerUnixSocketMode socket
+        Nothing ->
+          panic "Cannot run with socket on non-unix plattforms."
     Nothing ->
       do
         putStrLn $ ("Listening on port " :: Text) <> show configServerPort
diff --git a/src/PostgREST/CLI.hs b/src/PostgREST/CLI.hs
index 13a76df8d9..84a9611ce0 100644
--- a/src/PostgREST/CLI.hs
+++ b/src/PostgREST/CLI.hs
@@ -31,8 +31,8 @@ import qualified PostgREST.Config   as Config
 import Protolude hiding (hPutStrLn)
 
 
-main :: App.SignalHandlerInstaller -> App.SocketRunner -> CLI -> IO ()
-main installSignalHandlers runAppInSocket CLI{cliCommand, cliPath} = do
+main :: App.SignalHandlerInstaller -> Maybe App.SocketRunner -> CLI -> IO ()
+main installSignalHandlers runAppWithSocket CLI{cliCommand, cliPath} = do
   conf@AppConfig{..} <-
     either panic identity <$> Config.readAppConfig mempty cliPath Nothing
   appState <- AppState.init conf
@@ -47,7 +47,7 @@ main installSignalHandlers runAppInSocket CLI{cliCommand, cliPath} = do
     exec :: Command -> AppState -> IO ()
     exec CmdDumpConfig appState = putStr . Config.toText =<< AppState.getConfig appState
     exec CmdDumpSchema appState = putStrLn =<< dumpSchema appState
-    exec CmdRun appState = App.run installSignalHandlers runAppInSocket appState
+    exec CmdRun appState = App.run installSignalHandlers runAppWithSocket appState
 
 -- | Dump DbStructure schema to JSON
 dumpSchema :: AppState -> IO LBS.ByteString
diff --git a/src/PostgREST/Unix.hs b/src/PostgREST/Unix.hs
index ddae782cc1..86d42bacc6 100644
--- a/src/PostgREST/Unix.hs
+++ b/src/PostgREST/Unix.hs
@@ -1,5 +1,5 @@
 module PostgREST.Unix
-  ( runAppInSocket
+  ( runAppWithSocket
   , installSignalHandlers
   ) where
 
@@ -20,8 +20,8 @@ import Protolude
 
 
 -- | Run the PostgREST application with user defined socket.
-runAppInSocket :: Warp.Settings -> Application -> FileMode -> FilePath -> IO ()
-runAppInSocket settings app socketFileMode socketFilePath =
+runAppWithSocket :: Warp.Settings -> Application -> FileMode -> FilePath -> IO ()
+runAppWithSocket settings app socketFileMode socketFilePath =
   bracket createAndBindSocket Socket.close $ \socket -> do
     putStrLn $ ("Listening on unix socket " :: Text) <> show socketFilePath
     Socket.listen socket Socket.maxListenQueue