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-rw-r--r--src/tools/rust-analyzer/crates/proc-macro-api/Cargo.toml31
-rw-r--r--src/tools/rust-analyzer/crates/proc-macro-api/src/lib.rs181
-rw-r--r--src/tools/rust-analyzer/crates/proc-macro-api/src/msg.rs154
-rw-r--r--src/tools/rust-analyzer/crates/proc-macro-api/src/msg/flat.rs328
-rw-r--r--src/tools/rust-analyzer/crates/proc-macro-api/src/process.rs107
-rw-r--r--src/tools/rust-analyzer/crates/proc-macro-api/src/version.rs151
6 files changed, 952 insertions, 0 deletions
diff --git a/src/tools/rust-analyzer/crates/proc-macro-api/Cargo.toml b/src/tools/rust-analyzer/crates/proc-macro-api/Cargo.toml
new file mode 100644
index 000000000..85a1c13fe
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/proc-macro-api/Cargo.toml
@@ -0,0 +1,31 @@
+[package]
+name = "proc-macro-api"
+version = "0.0.0"
+description = "TBD"
+license = "MIT OR Apache-2.0"
+edition = "2021"
+rust-version = "1.57"
+
+[lib]
+doctest = false
+
+[dependencies]
+object = { version = "0.29.0", default-features = false, features = [
+ "std",
+ "read_core",
+ "elf",
+ "macho",
+ "pe",
+] }
+serde = { version = "1.0.137", features = ["derive"] }
+serde_json = { version = "1.0.81", features = ["unbounded_depth"] }
+tracing = "0.1.35"
+memmap2 = "0.5.4"
+snap = "1.0.5"
+
+paths = { path = "../paths", version = "0.0.0" }
+tt = { path = "../tt", version = "0.0.0" }
+stdx = { path = "../stdx", version = "0.0.0" }
+profile = { path = "../profile", version = "0.0.0" }
+# Intentionally *not* depend on anything salsa-related
+# base-db = { path = "../base-db", version = "0.0.0" }
diff --git a/src/tools/rust-analyzer/crates/proc-macro-api/src/lib.rs b/src/tools/rust-analyzer/crates/proc-macro-api/src/lib.rs
new file mode 100644
index 000000000..d7010e825
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/proc-macro-api/src/lib.rs
@@ -0,0 +1,181 @@
+//! Client-side Proc-Macro crate
+//!
+//! We separate proc-macro expanding logic to an extern program to allow
+//! different implementations (e.g. wasm or dylib loading). And this crate
+//! is used to provide basic infrastructure for communication between two
+//! processes: Client (RA itself), Server (the external program)
+
+#![warn(rust_2018_idioms, unused_lifetimes, semicolon_in_expressions_from_macros)]
+
+pub mod msg;
+mod process;
+mod version;
+
+use paths::AbsPathBuf;
+use std::{
+ ffi::OsStr,
+ fmt, io,
+ sync::{Arc, Mutex},
+};
+
+use serde::{Deserialize, Serialize};
+use tt::Subtree;
+
+use crate::{
+ msg::{ExpandMacro, FlatTree, PanicMessage},
+ process::ProcMacroProcessSrv,
+};
+
+pub use version::{read_dylib_info, read_version, RustCInfo};
+
+#[derive(Copy, Clone, Eq, PartialEq, Debug, Serialize, Deserialize)]
+pub enum ProcMacroKind {
+ CustomDerive,
+ FuncLike,
+ Attr,
+}
+
+/// A handle to an external process which load dylibs with macros (.so or .dll)
+/// and runs actual macro expansion functions.
+#[derive(Debug)]
+pub struct ProcMacroServer {
+ /// Currently, the proc macro process expands all procedural macros sequentially.
+ ///
+ /// That means that concurrent salsa requests may block each other when expanding proc macros,
+ /// which is unfortunate, but simple and good enough for the time being.
+ ///
+ /// Therefore, we just wrap the `ProcMacroProcessSrv` in a mutex here.
+ process: Arc<Mutex<ProcMacroProcessSrv>>,
+}
+
+pub struct MacroDylib {
+ path: AbsPathBuf,
+}
+
+impl MacroDylib {
+ // FIXME: this is buggy due to TOCTOU, we should check the version in the
+ // macro process instead.
+ pub fn new(path: AbsPathBuf) -> io::Result<MacroDylib> {
+ let _p = profile::span("MacroDylib::new");
+
+ let info = version::read_dylib_info(&path)?;
+ if info.version.0 < 1 || info.version.1 < 47 {
+ let msg = format!("proc-macro {} built by {:#?} is not supported by Rust Analyzer, please update your rust version.", path.display(), info);
+ return Err(io::Error::new(io::ErrorKind::InvalidData, msg));
+ }
+
+ Ok(MacroDylib { path })
+ }
+}
+
+/// A handle to a specific macro (a `#[proc_macro]` annotated function).
+///
+/// It exists withing a context of a specific [`ProcMacroProcess`] -- currently
+/// we share a single expander process for all macros.
+#[derive(Debug, Clone)]
+pub struct ProcMacro {
+ process: Arc<Mutex<ProcMacroProcessSrv>>,
+ dylib_path: AbsPathBuf,
+ name: String,
+ kind: ProcMacroKind,
+}
+
+impl Eq for ProcMacro {}
+impl PartialEq for ProcMacro {
+ fn eq(&self, other: &Self) -> bool {
+ self.name == other.name
+ && self.kind == other.kind
+ && self.dylib_path == other.dylib_path
+ && Arc::ptr_eq(&self.process, &other.process)
+ }
+}
+
+pub struct ServerError {
+ pub message: String,
+ pub io: Option<io::Error>,
+}
+
+impl fmt::Display for ServerError {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ self.message.fmt(f)?;
+ if let Some(io) = &self.io {
+ f.write_str(": ")?;
+ io.fmt(f)?;
+ }
+ Ok(())
+ }
+}
+
+pub struct MacroPanic {
+ pub message: String,
+}
+
+impl ProcMacroServer {
+ /// Spawns an external process as the proc macro server and returns a client connected to it.
+ pub fn spawn(
+ process_path: AbsPathBuf,
+ args: impl IntoIterator<Item = impl AsRef<OsStr>>,
+ ) -> io::Result<ProcMacroServer> {
+ let process = ProcMacroProcessSrv::run(process_path, args)?;
+ Ok(ProcMacroServer { process: Arc::new(Mutex::new(process)) })
+ }
+
+ pub fn load_dylib(&self, dylib: MacroDylib) -> Result<Vec<ProcMacro>, ServerError> {
+ let _p = profile::span("ProcMacroClient::by_dylib_path");
+ let macros =
+ self.process.lock().unwrap_or_else(|e| e.into_inner()).find_proc_macros(&dylib.path)?;
+
+ match macros {
+ Ok(macros) => Ok(macros
+ .into_iter()
+ .map(|(name, kind)| ProcMacro {
+ process: self.process.clone(),
+ name,
+ kind,
+ dylib_path: dylib.path.clone(),
+ })
+ .collect()),
+ Err(message) => Err(ServerError { message, io: None }),
+ }
+ }
+}
+
+impl ProcMacro {
+ pub fn name(&self) -> &str {
+ &self.name
+ }
+
+ pub fn kind(&self) -> ProcMacroKind {
+ self.kind
+ }
+
+ pub fn expand(
+ &self,
+ subtree: &Subtree,
+ attr: Option<&Subtree>,
+ env: Vec<(String, String)>,
+ ) -> Result<Result<Subtree, PanicMessage>, ServerError> {
+ let current_dir = env
+ .iter()
+ .find(|(name, _)| name == "CARGO_MANIFEST_DIR")
+ .map(|(_, value)| value.clone());
+
+ let task = ExpandMacro {
+ macro_body: FlatTree::new(subtree),
+ macro_name: self.name.to_string(),
+ attributes: attr.map(FlatTree::new),
+ lib: self.dylib_path.to_path_buf().into(),
+ env,
+ current_dir,
+ };
+
+ let request = msg::Request::ExpandMacro(task);
+ let response = self.process.lock().unwrap_or_else(|e| e.into_inner()).send_task(request)?;
+ match response {
+ msg::Response::ExpandMacro(it) => Ok(it.map(FlatTree::to_subtree)),
+ msg::Response::ListMacros { .. } => {
+ Err(ServerError { message: "unexpected response".to_string(), io: None })
+ }
+ }
+ }
+}
diff --git a/src/tools/rust-analyzer/crates/proc-macro-api/src/msg.rs b/src/tools/rust-analyzer/crates/proc-macro-api/src/msg.rs
new file mode 100644
index 000000000..f9c2b9fda
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/proc-macro-api/src/msg.rs
@@ -0,0 +1,154 @@
+//! Defines messages for cross-process message passing based on `ndjson` wire protocol
+pub(crate) mod flat;
+
+use std::{
+ io::{self, BufRead, Write},
+ path::PathBuf,
+};
+
+use serde::{de::DeserializeOwned, Deserialize, Serialize};
+
+use crate::ProcMacroKind;
+
+pub use crate::msg::flat::FlatTree;
+
+#[derive(Debug, Serialize, Deserialize)]
+pub enum Request {
+ ListMacros { dylib_path: PathBuf },
+ ExpandMacro(ExpandMacro),
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+pub enum Response {
+ ListMacros(Result<Vec<(String, ProcMacroKind)>, String>),
+ ExpandMacro(Result<FlatTree, PanicMessage>),
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+pub struct PanicMessage(pub String);
+
+#[derive(Debug, Serialize, Deserialize)]
+pub struct ExpandMacro {
+ /// Argument of macro call.
+ ///
+ /// In custom derive this will be a struct or enum; in attribute-like macro - underlying
+ /// item; in function-like macro - the macro body.
+ pub macro_body: FlatTree,
+
+ /// Name of macro to expand.
+ ///
+ /// In custom derive this is the name of the derived trait (`Serialize`, `Getters`, etc.).
+ /// In attribute-like and function-like macros - single name of macro itself (`show_streams`).
+ pub macro_name: String,
+
+ /// Possible attributes for the attribute-like macros.
+ pub attributes: Option<FlatTree>,
+
+ pub lib: PathBuf,
+
+ /// Environment variables to set during macro expansion.
+ pub env: Vec<(String, String)>,
+
+ pub current_dir: Option<String>,
+}
+
+pub trait Message: Serialize + DeserializeOwned {
+ fn read(inp: &mut impl BufRead, buf: &mut String) -> io::Result<Option<Self>> {
+ Ok(match read_json(inp, buf)? {
+ None => None,
+ Some(text) => {
+ let mut deserializer = serde_json::Deserializer::from_str(text);
+ // Note that some proc-macro generate very deep syntax tree
+ // We have to disable the current limit of serde here
+ deserializer.disable_recursion_limit();
+ Some(Self::deserialize(&mut deserializer)?)
+ }
+ })
+ }
+ fn write(self, out: &mut impl Write) -> io::Result<()> {
+ let text = serde_json::to_string(&self)?;
+ write_json(out, &text)
+ }
+}
+
+impl Message for Request {}
+impl Message for Response {}
+
+fn read_json<'a>(inp: &mut impl BufRead, buf: &'a mut String) -> io::Result<Option<&'a String>> {
+ loop {
+ buf.clear();
+
+ inp.read_line(buf)?;
+ buf.pop(); // Remove trailing '\n'
+
+ if buf.is_empty() {
+ return Ok(None);
+ }
+
+ // Some ill behaved macro try to use stdout for debugging
+ // We ignore it here
+ if !buf.starts_with('{') {
+ tracing::error!("proc-macro tried to print : {}", buf);
+ continue;
+ }
+
+ return Ok(Some(buf));
+ }
+}
+
+fn write_json(out: &mut impl Write, msg: &str) -> io::Result<()> {
+ tracing::debug!("> {}", msg);
+ out.write_all(msg.as_bytes())?;
+ out.write_all(b"\n")?;
+ out.flush()?;
+ Ok(())
+}
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+ use tt::*;
+
+ fn fixture_token_tree() -> Subtree {
+ let mut subtree = Subtree::default();
+ subtree
+ .token_trees
+ .push(TokenTree::Leaf(Ident { text: "struct".into(), id: TokenId(0) }.into()));
+ subtree
+ .token_trees
+ .push(TokenTree::Leaf(Ident { text: "Foo".into(), id: TokenId(1) }.into()));
+ subtree.token_trees.push(TokenTree::Leaf(Leaf::Literal(Literal {
+ text: "Foo".into(),
+ id: TokenId::unspecified(),
+ })));
+ subtree.token_trees.push(TokenTree::Leaf(Leaf::Punct(Punct {
+ char: '@',
+ id: TokenId::unspecified(),
+ spacing: Spacing::Joint,
+ })));
+ subtree.token_trees.push(TokenTree::Subtree(Subtree {
+ delimiter: Some(Delimiter { id: TokenId(2), kind: DelimiterKind::Brace }),
+ token_trees: vec![],
+ }));
+ subtree
+ }
+
+ #[test]
+ fn test_proc_macro_rpc_works() {
+ let tt = fixture_token_tree();
+ let task = ExpandMacro {
+ macro_body: FlatTree::new(&tt),
+ macro_name: Default::default(),
+ attributes: None,
+ lib: std::env::current_dir().unwrap(),
+ env: Default::default(),
+ current_dir: Default::default(),
+ };
+
+ let json = serde_json::to_string(&task).unwrap();
+ // println!("{}", json);
+ let back: ExpandMacro = serde_json::from_str(&json).unwrap();
+
+ assert_eq!(tt, back.macro_body.to_subtree());
+ }
+}
diff --git a/src/tools/rust-analyzer/crates/proc-macro-api/src/msg/flat.rs b/src/tools/rust-analyzer/crates/proc-macro-api/src/msg/flat.rs
new file mode 100644
index 000000000..8437444e1
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/proc-macro-api/src/msg/flat.rs
@@ -0,0 +1,328 @@
+//! Serialization-friendly representation of `tt::Subtree`.
+//!
+//! It is possible to serialize `Subtree` as is, as a tree, but using
+//! arbitrary-nested trees in JSON is problematic, as they can cause the JSON
+//! parser to overflow the stack.
+//!
+//! Additionally, such implementation would be pretty verbose, and we do care
+//! about performance here a bit.
+//!
+//! So what this module does is dumping a `tt::Subtree` into a bunch of flat
+//! array of numbers. See the test in the parent module to get an example
+//! output.
+//!
+//! ```json
+//! {
+//! // Array of subtrees, each subtree is represented by 4 numbers:
+//! // id of delimiter, delimiter kind, index of first child in `token_tree`,
+//! // index of last child in `token_tree`
+//! "subtree":[4294967295,0,0,5,2,2,5,5],
+//! // 2 ints per literal: [token id, index into `text`]
+//! "literal":[4294967295,1],
+//! // 3 ints per punct: [token id, char, spacing]
+//! "punct":[4294967295,64,1],
+//! // 2 ints per ident: [token id, index into `text`]
+//! "ident": [0,0,1,1],
+//! // children of all subtrees, concatenated. Each child is represented as `index << 2 | tag`
+//! // where tag denotes one of subtree, literal, punct or ident.
+//! "token_tree":[3,7,1,4],
+//! // Strings shared by idents and literals
+//! "text": ["struct","Foo"]
+//! }
+//! ```
+//!
+//! We probably should replace most of the code here with bincode someday, but,
+//! as we don't have bincode in Cargo.toml yet, lets stick with serde_json for
+//! the time being.
+
+use std::{
+ collections::{HashMap, VecDeque},
+ convert::TryInto,
+};
+
+use serde::{Deserialize, Serialize};
+use tt::TokenId;
+
+#[derive(Serialize, Deserialize, Debug)]
+pub struct FlatTree {
+ subtree: Vec<u32>,
+ literal: Vec<u32>,
+ punct: Vec<u32>,
+ ident: Vec<u32>,
+ token_tree: Vec<u32>,
+ text: Vec<String>,
+}
+
+struct SubtreeRepr {
+ id: tt::TokenId,
+ kind: Option<tt::DelimiterKind>,
+ tt: [u32; 2],
+}
+
+struct LiteralRepr {
+ id: tt::TokenId,
+ text: u32,
+}
+
+struct PunctRepr {
+ id: tt::TokenId,
+ char: char,
+ spacing: tt::Spacing,
+}
+
+struct IdentRepr {
+ id: tt::TokenId,
+ text: u32,
+}
+
+impl FlatTree {
+ pub fn new(subtree: &tt::Subtree) -> FlatTree {
+ let mut w = Writer {
+ string_table: HashMap::new(),
+ work: VecDeque::new(),
+
+ subtree: Vec::new(),
+ literal: Vec::new(),
+ punct: Vec::new(),
+ ident: Vec::new(),
+ token_tree: Vec::new(),
+ text: Vec::new(),
+ };
+ w.write(subtree);
+
+ return FlatTree {
+ subtree: write_vec(w.subtree, SubtreeRepr::write),
+ literal: write_vec(w.literal, LiteralRepr::write),
+ punct: write_vec(w.punct, PunctRepr::write),
+ ident: write_vec(w.ident, IdentRepr::write),
+ token_tree: w.token_tree,
+ text: w.text,
+ };
+
+ fn write_vec<T, F: Fn(T) -> [u32; N], const N: usize>(xs: Vec<T>, f: F) -> Vec<u32> {
+ xs.into_iter().flat_map(f).collect()
+ }
+ }
+
+ pub fn to_subtree(self) -> tt::Subtree {
+ return Reader {
+ subtree: read_vec(self.subtree, SubtreeRepr::read),
+ literal: read_vec(self.literal, LiteralRepr::read),
+ punct: read_vec(self.punct, PunctRepr::read),
+ ident: read_vec(self.ident, IdentRepr::read),
+ token_tree: self.token_tree,
+ text: self.text,
+ }
+ .read();
+
+ fn read_vec<T, F: Fn([u32; N]) -> T, const N: usize>(xs: Vec<u32>, f: F) -> Vec<T> {
+ let mut chunks = xs.chunks_exact(N);
+ let res = chunks.by_ref().map(|chunk| f(chunk.try_into().unwrap())).collect();
+ assert!(chunks.remainder().is_empty());
+ res
+ }
+ }
+}
+
+impl SubtreeRepr {
+ fn write(self) -> [u32; 4] {
+ let kind = match self.kind {
+ None => 0,
+ Some(tt::DelimiterKind::Parenthesis) => 1,
+ Some(tt::DelimiterKind::Brace) => 2,
+ Some(tt::DelimiterKind::Bracket) => 3,
+ };
+ [self.id.0, kind, self.tt[0], self.tt[1]]
+ }
+ fn read([id, kind, lo, len]: [u32; 4]) -> SubtreeRepr {
+ let kind = match kind {
+ 0 => None,
+ 1 => Some(tt::DelimiterKind::Parenthesis),
+ 2 => Some(tt::DelimiterKind::Brace),
+ 3 => Some(tt::DelimiterKind::Bracket),
+ other => panic!("bad kind {}", other),
+ };
+ SubtreeRepr { id: TokenId(id), kind, tt: [lo, len] }
+ }
+}
+
+impl LiteralRepr {
+ fn write(self) -> [u32; 2] {
+ [self.id.0, self.text]
+ }
+ fn read([id, text]: [u32; 2]) -> LiteralRepr {
+ LiteralRepr { id: TokenId(id), text }
+ }
+}
+
+impl PunctRepr {
+ fn write(self) -> [u32; 3] {
+ let spacing = match self.spacing {
+ tt::Spacing::Alone => 0,
+ tt::Spacing::Joint => 1,
+ };
+ [self.id.0, self.char as u32, spacing]
+ }
+ fn read([id, char, spacing]: [u32; 3]) -> PunctRepr {
+ let spacing = match spacing {
+ 0 => tt::Spacing::Alone,
+ 1 => tt::Spacing::Joint,
+ other => panic!("bad spacing {}", other),
+ };
+ PunctRepr { id: TokenId(id), char: char.try_into().unwrap(), spacing }
+ }
+}
+
+impl IdentRepr {
+ fn write(self) -> [u32; 2] {
+ [self.id.0, self.text]
+ }
+ fn read(data: [u32; 2]) -> IdentRepr {
+ IdentRepr { id: TokenId(data[0]), text: data[1] }
+ }
+}
+
+struct Writer<'a> {
+ work: VecDeque<(usize, &'a tt::Subtree)>,
+ string_table: HashMap<&'a str, u32>,
+
+ subtree: Vec<SubtreeRepr>,
+ literal: Vec<LiteralRepr>,
+ punct: Vec<PunctRepr>,
+ ident: Vec<IdentRepr>,
+ token_tree: Vec<u32>,
+ text: Vec<String>,
+}
+
+impl<'a> Writer<'a> {
+ fn write(&mut self, root: &'a tt::Subtree) {
+ self.enqueue(root);
+ while let Some((idx, subtree)) = self.work.pop_front() {
+ self.subtree(idx, subtree);
+ }
+ }
+
+ fn subtree(&mut self, idx: usize, subtree: &'a tt::Subtree) {
+ let mut first_tt = self.token_tree.len();
+ let n_tt = subtree.token_trees.len();
+ self.token_tree.resize(first_tt + n_tt, !0);
+
+ self.subtree[idx].tt = [first_tt as u32, (first_tt + n_tt) as u32];
+
+ for child in &subtree.token_trees {
+ let idx_tag = match child {
+ tt::TokenTree::Subtree(it) => {
+ let idx = self.enqueue(it);
+ idx << 2 | 0b00
+ }
+ tt::TokenTree::Leaf(leaf) => match leaf {
+ tt::Leaf::Literal(lit) => {
+ let idx = self.literal.len() as u32;
+ let text = self.intern(&lit.text);
+ self.literal.push(LiteralRepr { id: lit.id, text });
+ idx << 2 | 0b01
+ }
+ tt::Leaf::Punct(punct) => {
+ let idx = self.punct.len() as u32;
+ self.punct.push(PunctRepr {
+ char: punct.char,
+ spacing: punct.spacing,
+ id: punct.id,
+ });
+ idx << 2 | 0b10
+ }
+ tt::Leaf::Ident(ident) => {
+ let idx = self.ident.len() as u32;
+ let text = self.intern(&ident.text);
+ self.ident.push(IdentRepr { id: ident.id, text });
+ idx << 2 | 0b11
+ }
+ },
+ };
+ self.token_tree[first_tt] = idx_tag;
+ first_tt += 1;
+ }
+ }
+
+ fn enqueue(&mut self, subtree: &'a tt::Subtree) -> u32 {
+ let idx = self.subtree.len();
+ let delimiter_id = subtree.delimiter.map_or(TokenId::unspecified(), |it| it.id);
+ let delimiter_kind = subtree.delimiter.map(|it| it.kind);
+ self.subtree.push(SubtreeRepr { id: delimiter_id, kind: delimiter_kind, tt: [!0, !0] });
+ self.work.push_back((idx, subtree));
+ idx as u32
+ }
+
+ pub(crate) fn intern(&mut self, text: &'a str) -> u32 {
+ let table = &mut self.text;
+ *self.string_table.entry(text).or_insert_with(|| {
+ let idx = table.len();
+ table.push(text.to_string());
+ idx as u32
+ })
+ }
+}
+
+struct Reader {
+ subtree: Vec<SubtreeRepr>,
+ literal: Vec<LiteralRepr>,
+ punct: Vec<PunctRepr>,
+ ident: Vec<IdentRepr>,
+ token_tree: Vec<u32>,
+ text: Vec<String>,
+}
+
+impl Reader {
+ pub(crate) fn read(self) -> tt::Subtree {
+ let mut res: Vec<Option<tt::Subtree>> = vec![None; self.subtree.len()];
+ for i in (0..self.subtree.len()).rev() {
+ let repr = &self.subtree[i];
+ let token_trees = &self.token_tree[repr.tt[0] as usize..repr.tt[1] as usize];
+ let s = tt::Subtree {
+ delimiter: repr.kind.map(|kind| tt::Delimiter { id: repr.id, kind }),
+ token_trees: token_trees
+ .iter()
+ .copied()
+ .map(|idx_tag| {
+ let tag = idx_tag & 0b11;
+ let idx = (idx_tag >> 2) as usize;
+ match tag {
+ // XXX: we iterate subtrees in reverse to guarantee
+ // that this unwrap doesn't fire.
+ 0b00 => res[idx].take().unwrap().into(),
+ 0b01 => {
+ let repr = &self.literal[idx];
+ tt::Leaf::Literal(tt::Literal {
+ text: self.text[repr.text as usize].as_str().into(),
+ id: repr.id,
+ })
+ .into()
+ }
+ 0b10 => {
+ let repr = &self.punct[idx];
+ tt::Leaf::Punct(tt::Punct {
+ char: repr.char,
+ spacing: repr.spacing,
+ id: repr.id,
+ })
+ .into()
+ }
+ 0b11 => {
+ let repr = &self.ident[idx];
+ tt::Leaf::Ident(tt::Ident {
+ text: self.text[repr.text as usize].as_str().into(),
+ id: repr.id,
+ })
+ .into()
+ }
+ other => panic!("bad tag: {}", other),
+ }
+ })
+ .collect(),
+ };
+ res[i] = Some(s);
+ }
+
+ res[0].take().unwrap()
+ }
+}
diff --git a/src/tools/rust-analyzer/crates/proc-macro-api/src/process.rs b/src/tools/rust-analyzer/crates/proc-macro-api/src/process.rs
new file mode 100644
index 000000000..c4018d3b3
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/proc-macro-api/src/process.rs
@@ -0,0 +1,107 @@
+//! Handle process life-time and message passing for proc-macro client
+
+use std::{
+ ffi::{OsStr, OsString},
+ io::{self, BufRead, BufReader, Write},
+ process::{Child, ChildStdin, ChildStdout, Command, Stdio},
+};
+
+use paths::{AbsPath, AbsPathBuf};
+use stdx::JodChild;
+
+use crate::{
+ msg::{Message, Request, Response},
+ ProcMacroKind, ServerError,
+};
+
+#[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: process, stdin, stdout };
+
+ Ok(srv)
+ }
+
+ pub(crate) fn find_proc_macros(
+ &mut self,
+ dylib_path: &AbsPath,
+ ) -> Result<Result<Vec<(String, ProcMacroKind)>, String>, ServerError> {
+ let request = Request::ListMacros { dylib_path: dylib_path.to_path_buf().into() };
+
+ let response = self.send_task(request)?;
+
+ match response {
+ Response::ListMacros(it) => Ok(it),
+ Response::ExpandMacro { .. } => {
+ Err(ServerError { message: "unexpected response".to_string(), io: None })
+ }
+ }
+ }
+
+ pub(crate) fn send_task(&mut self, req: Request) -> Result<Response, ServerError> {
+ let mut buf = String::new();
+ send_request(&mut self.stdin, &mut self.stdout, req, &mut buf)
+ }
+}
+
+#[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)
+ .env("RUST_ANALYZER_INTERNALS_DO_NOT_USE", "this is unstable")
+ .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,
+) -> Result<Response, ServerError> {
+ req.write(&mut writer)
+ .map_err(|err| ServerError { message: "failed to write request".into(), io: Some(err) })?;
+ let res = Response::read(&mut reader, buf)
+ .map_err(|err| ServerError { message: "failed to read response".into(), io: Some(err) })?;
+ res.ok_or_else(|| ServerError { message: "server exited".into(), io: None })
+}
diff --git a/src/tools/rust-analyzer/crates/proc-macro-api/src/version.rs b/src/tools/rust-analyzer/crates/proc-macro-api/src/version.rs
new file mode 100644
index 000000000..030531b80
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/proc-macro-api/src/version.rs
@@ -0,0 +1,151 @@
+//! Reading proc-macro rustc version information from binary data
+
+use std::{
+ fs::File,
+ io::{self, Read},
+};
+
+use memmap2::Mmap;
+use object::read::{File as BinaryFile, Object, ObjectSection};
+use paths::AbsPath;
+use snap::read::FrameDecoder as SnapDecoder;
+
+#[derive(Debug)]
+pub struct RustCInfo {
+ pub version: (usize, usize, usize),
+ pub channel: String,
+ pub commit: Option<String>,
+ pub date: Option<String>,
+ // something like "rustc 1.58.1 (db9d1b20b 2022-01-20)"
+ pub version_string: String,
+}
+
+/// Read rustc dylib information
+pub fn read_dylib_info(dylib_path: &AbsPath) -> io::Result<RustCInfo> {
+ macro_rules! err {
+ ($e:literal) => {
+ io::Error::new(io::ErrorKind::InvalidData, $e)
+ };
+ }
+
+ let ver_str = read_version(dylib_path)?;
+ let mut items = ver_str.split_whitespace();
+ let tag = items.next().ok_or_else(|| err!("version format error"))?;
+ if tag != "rustc" {
+ return Err(err!("version format error (No rustc tag)"));
+ }
+
+ let version_part = items.next().ok_or_else(|| err!("no version string"))?;
+ let mut version_parts = version_part.split('-');
+ let version = version_parts.next().ok_or_else(|| err!("no version"))?;
+ let channel = version_parts.next().unwrap_or_default().to_string();
+
+ let commit = match items.next() {
+ Some(commit) => {
+ match commit.len() {
+ 0 => None,
+ _ => Some(commit[1..].to_string() /* remove ( */),
+ }
+ }
+ None => None,
+ };
+ let date = match items.next() {
+ Some(date) => {
+ match date.len() {
+ 0 => None,
+ _ => Some(date[0..date.len() - 2].to_string() /* remove ) */),
+ }
+ }
+ None => None,
+ };
+
+ let version_numbers = version
+ .split('.')
+ .map(|it| it.parse::<usize>())
+ .collect::<Result<Vec<_>, _>>()
+ .map_err(|_| err!("version number error"))?;
+
+ if version_numbers.len() != 3 {
+ return Err(err!("version number format error"));
+ }
+ let version = (version_numbers[0], version_numbers[1], version_numbers[2]);
+
+ Ok(RustCInfo { version, channel, commit, date, version_string: ver_str })
+}
+
+/// This is used inside read_version() to locate the ".rustc" section
+/// from a proc macro crate's binary file.
+fn read_section<'a>(dylib_binary: &'a [u8], section_name: &str) -> io::Result<&'a [u8]> {
+ BinaryFile::parse(dylib_binary)
+ .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?
+ .section_by_name(section_name)
+ .ok_or_else(|| io::Error::new(io::ErrorKind::InvalidData, "section read error"))?
+ .data()
+ .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))
+}
+
+/// Check the version of rustc that was used to compile a proc macro crate's
+///
+/// binary file.
+/// A proc macro crate binary's ".rustc" section has following byte layout:
+/// * [b'r',b'u',b's',b't',0,0,0,5] is the first 8 bytes
+/// * ff060000 734e6150 is followed, it's the snappy format magic bytes,
+/// means bytes from here(including this sequence) are compressed in
+/// snappy compression format. Version info is inside here, so decompress
+/// this.
+/// The bytes you get after decompressing the snappy format portion has
+/// following layout:
+/// * [b'r',b'u',b's',b't',0,0,0,5] is the first 8 bytes(again)
+/// * [crate root bytes] next 4 bytes is to store crate root position,
+/// according to rustc's source code comment
+/// * [length byte] next 1 byte tells us how many bytes we should read next
+/// for the version string's utf8 bytes
+/// * [version string bytes encoded in utf8] <- GET THIS BOI
+/// * [some more bytes that we don't really care but about still there] :-)
+/// Check this issue for more about the bytes layout:
+/// <https://github.com/rust-lang/rust-analyzer/issues/6174>
+pub fn read_version(dylib_path: &AbsPath) -> io::Result<String> {
+ let dylib_file = File::open(dylib_path)?;
+ let dylib_mmaped = unsafe { Mmap::map(&dylib_file) }?;
+
+ let dot_rustc = read_section(&dylib_mmaped, ".rustc")?;
+
+ // check if magic is valid
+ if &dot_rustc[0..4] != b"rust" {
+ return Err(io::Error::new(
+ io::ErrorKind::InvalidData,
+ format!("unknown metadata magic, expected `rust`, found `{:?}`", &dot_rustc[0..4]),
+ ));
+ }
+ let version = u32::from_be_bytes([dot_rustc[4], dot_rustc[5], dot_rustc[6], dot_rustc[7]]);
+ // Last supported version is:
+ // https://github.com/rust-lang/rust/commit/0696e79f2740ad89309269b460579e548a5cd632
+ match version {
+ 5 | 6 => {}
+ _ => {
+ return Err(io::Error::new(
+ io::ErrorKind::InvalidData,
+ format!("unsupported metadata version {}", version),
+ ));
+ }
+ }
+
+ let snappy_portion = &dot_rustc[8..];
+
+ let mut snappy_decoder = SnapDecoder::new(snappy_portion);
+
+ // the bytes before version string bytes, so this basically is:
+ // 8 bytes for [b'r',b'u',b's',b't',0,0,0,5]
+ // 4 bytes for [crate root bytes]
+ // 1 byte for length of version string
+ // so 13 bytes in total, and we should check the 13th byte
+ // to know the length
+ let mut bytes_before_version = [0u8; 13];
+ snappy_decoder.read_exact(&mut bytes_before_version)?;
+ let length = bytes_before_version[12];
+
+ let mut version_string_utf8 = vec![0u8; length as usize];
+ snappy_decoder.read_exact(&mut version_string_utf8)?;
+ let version_string = String::from_utf8(version_string_utf8);
+ version_string.map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))
+}