1 //! Handle process life-time and message passing for proc-macro client
4 convert::{TryFrom, TryInto},
5 ffi::{OsStr, OsString},
6 io::{self, BufRead, BufReader, Write},
8 process::{Child, Command, Stdio},
12 use crossbeam_channel::{bounded, Receiver, Sender};
16 msg::{ErrorCode, Message, Request, Response, ResponseError},
17 rpc::{ListMacrosResult, ListMacrosTask, ProcMacroKind},
20 #[derive(Debug, Default)]
21 pub(crate) struct ProcMacroProcessSrv {
22 inner: Weak<Sender<Task>>,
26 pub(crate) struct ProcMacroProcessThread {
27 // XXX: drop order is significant
28 sender: Arc<Sender<Task>>,
29 handle: jod_thread::JoinHandle<()>,
32 impl ProcMacroProcessSrv {
34 process_path: PathBuf,
35 args: impl IntoIterator<Item = impl AsRef<OsStr>>,
36 ) -> io::Result<(ProcMacroProcessThread, ProcMacroProcessSrv)> {
37 let process = Process::run(process_path, args)?;
39 let (task_tx, task_rx) = bounded(0);
40 let handle = jod_thread::spawn(move || {
41 client_loop(task_rx, process);
44 let task_tx = Arc::new(task_tx);
45 let srv = ProcMacroProcessSrv { inner: Arc::downgrade(&task_tx) };
46 let thread = ProcMacroProcessThread { handle, sender: task_tx };
51 pub(crate) fn find_proc_macros(
54 ) -> Result<Vec<(String, ProcMacroKind)>, tt::ExpansionError> {
55 let task = ListMacrosTask { lib: dylib_path.to_path_buf() };
57 let result: ListMacrosResult = self.send_task(Request::ListMacro(task))?;
61 pub(crate) fn send_task<R>(&self, req: Request) -> Result<R, tt::ExpansionError>
63 R: TryFrom<Response, Error = &'static str>,
65 let (result_tx, result_rx) = bounded(0);
66 let sender = match self.inner.upgrade() {
67 None => return Err(tt::ExpansionError::Unknown("proc macro process is closed".into())),
71 .send(Task { req, result_tx })
72 .map_err(|_| tt::ExpansionError::Unknown("proc macro server crashed".into()))?;
76 .map_err(|_| tt::ExpansionError::Unknown("proc macro server crashed".into()))?;
79 Some(Response::Error(err)) => {
80 return Err(tt::ExpansionError::ExpansionError(err.message));
82 Some(res) => Ok(res.try_into().map_err(|err| {
83 tt::ExpansionError::Unknown(format!("Fail to get response, reason : {:#?} ", err))
85 None => Err(tt::ExpansionError::Unknown("Empty result".into())),
90 fn client_loop(task_rx: Receiver<Task>, mut process: Process) {
91 let (mut stdin, mut stdout) = process.stdio().expect("couldn't access child stdio");
93 for Task { req, result_tx } in task_rx {
94 match send_request(&mut stdin, &mut stdout, req) {
95 Ok(res) => result_tx.send(res).unwrap(),
98 "proc macro server crashed, server process state: {:?}, server request error: {:?}",
99 process.child.try_wait(),
102 let res = Response::Error(ResponseError {
103 code: ErrorCode::ServerErrorEnd,
104 message: "proc macro server crashed".into(),
106 result_tx.send(res.into()).unwrap();
116 result_tx: Sender<Option<Response>>,
126 args: impl IntoIterator<Item = impl AsRef<OsStr>>,
127 ) -> io::Result<Process> {
128 let args: Vec<OsString> = args.into_iter().map(|s| s.as_ref().into()).collect();
129 let child = JodChild(mk_child(&path, &args)?);
130 Ok(Process { child })
133 fn stdio(&mut self) -> Option<(impl Write, impl BufRead)> {
134 let stdin = self.child.stdin.take()?;
135 let stdout = self.child.stdout.take()?;
136 let read = BufReader::new(stdout);
142 fn mk_child(path: &Path, args: impl IntoIterator<Item = impl AsRef<OsStr>>) -> io::Result<Child> {
145 .stdin(Stdio::piped())
146 .stdout(Stdio::piped())
147 .stderr(Stdio::inherit())
152 mut writer: &mut impl Write,
153 mut reader: &mut impl BufRead,
155 ) -> io::Result<Option<Response>> {
156 req.write(&mut writer)?;
157 Ok(Response::read(&mut reader)?)