add gen_lsp_server

crates/gen_lsp_server/src/stdio.rs

@@ -0,0 +1,49 @@
+use std::{
+    thread,
+    io::{
+        stdout, stdin,
+    },
+};
+
+use crossbeam_channel::{Receiver, Sender, bounded};
+
+use {RawMessage, Result};
+
+pub fn stdio_transport() -> (Receiver<RawMessage>, Sender<RawMessage>, Threads) {
+    let (writer_sender, mut writer_receiver) = bounded::<RawMessage>(16);
+    let writer = thread::spawn(move || {
+        let stdout = stdout();
+        let mut stdout = stdout.lock();
+        writer_receiver.try_for_each(|it| it.write(&mut stdout))?;
+        Ok(())
+    });
+    let (reader_sender, reader_receiver) = bounded::<RawMessage>(16);
+    let reader = thread::spawn(move || {
+        let stdin = stdin();
+        let mut stdin = stdin.lock();
+        while let Some(msg) = RawMessage::read(&mut stdin)? {
+            reader_sender.send(msg);
+        }
+        Ok(())
+    });
+    let threads = Threads { reader, writer };
+    (reader_receiver, writer_sender, threads)
+}
+
+pub struct Threads {
+    reader: thread::JoinHandle<Result<()>>,
+    writer: thread::JoinHandle<Result<()>>,
+}
+
+impl Threads {
+    pub fn join(self) -> Result<()> {
+        match self.reader.join() {
+            Ok(r) => r?,
+            Err(_) => bail!("reader panicked"),
+        }
+        match self.writer.join() {
+            Ok(r) => r,
+            Err(_) => bail!("writer panicked"),
+        }
+    }
+}