rust/crates/proc_macro_api/src/process.rs

125 lines
3.6 KiB
Rust

//! Handle process life-time and message passing for proc-macro client
use std::{
convert::{TryFrom, TryInto},
ffi::{OsStr, OsString},
io::{self, BufRead, BufReader, Write},
process::{Child, ChildStdin, ChildStdout, Command, Stdio},
};
use paths::{AbsPath, AbsPathBuf};
use stdx::JodChild;
use crate::{
msg::{ErrorCode, Message, Request, Response, ResponseError},
rpc::{ListMacrosResult, ListMacrosTask, ProcMacroKind},
};
#[derive(Debug)]
pub(crate) struct ProcMacroProcessSrv {
process: Process,
stdin: ChildStdin,
stdout: BufReader<ChildStdout>,
}
impl ProcMacroProcessSrv {
pub(crate) fn run(
process_path: AbsPathBuf,
args: impl IntoIterator<Item = impl AsRef<OsStr>>,
) -> io::Result<ProcMacroProcessSrv> {
let mut process = Process::run(process_path, args)?;
let (stdin, stdout) = process.stdio().expect("couldn't access child stdio");
let srv = ProcMacroProcessSrv { process, stdin, stdout };
Ok(srv)
}
pub(crate) fn find_proc_macros(
&mut self,
dylib_path: &AbsPath,
) -> Result<Vec<(String, ProcMacroKind)>, tt::ExpansionError> {
let task = ListMacrosTask { lib: dylib_path.to_path_buf() };
let result: ListMacrosResult = self.send_task(Request::ListMacro(task))?;
Ok(result.macros)
}
pub(crate) fn send_task<R>(&mut self, req: Request) -> Result<R, tt::ExpansionError>
where
R: TryFrom<Response, Error = &'static str>,
{
let mut buf = String::new();
let res = match send_request(&mut self.stdin, &mut self.stdout, req, &mut buf) {
Ok(res) => res,
Err(err) => {
let result = self.process.child.try_wait();
log::error!(
"proc macro server crashed, server process state: {:?}, server request error: {:?}",
result,
err
);
let res = Response::Error(ResponseError {
code: ErrorCode::ServerErrorEnd,
message: "proc macro server crashed".into(),
});
Some(res)
}
};
match res {
Some(Response::Error(err)) => Err(tt::ExpansionError::ExpansionError(err.message)),
Some(res) => Ok(res.try_into().map_err(|err| {
tt::ExpansionError::Unknown(format!("Fail to get response, reason : {:#?} ", err))
})?),
None => Err(tt::ExpansionError::Unknown("Empty result".into())),
}
}
}
#[derive(Debug)]
struct Process {
child: JodChild,
}
impl Process {
fn run(
path: AbsPathBuf,
args: impl IntoIterator<Item = impl AsRef<OsStr>>,
) -> io::Result<Process> {
let args: Vec<OsString> = args.into_iter().map(|s| s.as_ref().into()).collect();
let child = JodChild(mk_child(&path, &args)?);
Ok(Process { child })
}
fn stdio(&mut self) -> Option<(ChildStdin, BufReader<ChildStdout>)> {
let stdin = self.child.stdin.take()?;
let stdout = self.child.stdout.take()?;
let read = BufReader::new(stdout);
Some((stdin, read))
}
}
fn mk_child(
path: &AbsPath,
args: impl IntoIterator<Item = impl AsRef<OsStr>>,
) -> io::Result<Child> {
Command::new(path.as_os_str())
.args(args)
.stdin(Stdio::piped())
.stdout(Stdio::piped())
.stderr(Stdio::inherit())
.spawn()
}
fn send_request(
mut writer: &mut impl Write,
mut reader: &mut impl BufRead,
req: Request,
buf: &mut String,
) -> io::Result<Option<Response>> {
req.write(&mut writer)?;
Response::read(&mut reader, buf)
}