Add wasm32-specific patch to warn on runtimes without non-blocking stdin support

Author: andy0130tw

agda-language-server.cabal

@@ -110,6 +110,9 @@ library
   if flag(Agda-2-7-0-1)
     build-depends:
         Agda ==2.7.0.1
+  if arch(wasm32)
+    build-depends:
+        unix >=2.8.0.0 && <2.9
 
 executable als
   main-is: Main.hs

src/Server.hs

@@ -28,6 +28,12 @@ import qualified Server.Handler as Handler
 import Switchboard (Switchboard, agdaCustomMethod)
 import qualified Switchboard
 
+#if defined(wasm32_HOST_ARCH)
+import Agda.Utils.IO (catchIO)
+import System.IO (hPutStrLn, stderr)
+import System.Posix.IO (stdInput, setFdOption, FdOption (..))
+#endif
+
 --------------------------------------------------------------------------------
 
 run :: Options -> IO Int
@@ -44,6 +50,10 @@ run options = do
       -- Switchboard.destroy switchboard
       return 0
     Nothing -> do
+      #if defined(wasm32_HOST_ARCH)
+      liftIO $ setFdOption stdInput NonBlockingRead True
+        `catchIO` (\ e -> hPutStrLn stderr $ "Failed to enable nonblocking on stdin: " ++ (show e) ++ "\nThe WASM module might not behave correctly.")
+      #endif
       runServer (serverDefn options)
   where
     serverDefn :: Options -> ServerDefinition Config