1 files changed, 39 insertions, 0 deletions

diff --git a/crates/proc_macro_srv/src/cli.rs b/crates/proc_macro_srv/src/cli.rs
new file mode 100644
index 000000000..d428b9567
--- /dev/null
+++ b/crates/proc_macro_srv/src/cli.rs
@@ -0,0 +1,39 @@
+//! Driver for proc macro server
+
+use crate::ProcMacroSrv;
+use proc_macro_api::msg::{self, Message};
+use std::io;
+
+pub fn run() -> io::Result<()> {
+    let mut srv = ProcMacroSrv::default();
+
+    while let Some(req) = read_request()? {
+        let res = match req {
+            msg::Request::ListMacro(task) => srv.list_macros(&task).map(msg::Response::ListMacro),
+            msg::Request::ExpansionMacro(task) => {
+                srv.expand(&task).map(msg::Response::ExpansionMacro)
+            }
+        };
+
+        let msg = res.unwrap_or_else(|err| {
+            msg::Response::Error(msg::ResponseError {
+                code: msg::ErrorCode::ExpansionError,
+                message: err,
+            })
+        });
+
+        if let Err(err) = write_response(msg) {
+            eprintln!("Write message error: {}", err);
+        }
+    }
+
+    Ok(())
+}
+
+fn read_request() -> io::Result<Option<msg::Request>> {
+    msg::Request::read(&mut io::stdin().lock())
+}
+
+fn write_response(msg: msg::Response) -> io::Result<()> {
+    msg.write(&mut io::stdout().lock())
+}