diff options
Diffstat (limited to 'src/tools/rust-analyzer/crates/proc-macro-srv/src/abis/abi_1_64/proc_macro/bridge/client.rs')
| -rw-r--r-- | src/tools/rust-analyzer/crates/proc-macro-srv/src/abis/abi_1_64/proc_macro/bridge/client.rs | 529 |
1 files changed, 529 insertions, 0 deletions
diff --git a/src/tools/rust-analyzer/crates/proc-macro-srv/src/abis/abi_1_64/proc_macro/bridge/client.rs b/src/tools/rust-analyzer/crates/proc-macro-srv/src/abis/abi_1_64/proc_macro/bridge/client.rs new file mode 100644 index 000000000..22bda8ba5 --- /dev/null +++ b/src/tools/rust-analyzer/crates/proc-macro-srv/src/abis/abi_1_64/proc_macro/bridge/client.rs @@ -0,0 +1,529 @@ +//! Client-side types. + +use super::*; + +use std::marker::PhantomData; + +macro_rules! define_handles { + ( + 'owned: $($oty:ident,)* + 'interned: $($ity:ident,)* + ) => { + #[repr(C)] + #[allow(non_snake_case)] + pub struct HandleCounters { + $($oty: AtomicUsize,)* + $($ity: AtomicUsize,)* + } + + impl HandleCounters { + // FIXME(eddyb) use a reference to the `static COUNTERS`, instead of + // a wrapper `fn` pointer, once `const fn` can reference `static`s. + extern "C" fn get() -> &'static Self { + static COUNTERS: HandleCounters = HandleCounters { + $($oty: AtomicUsize::new(1),)* + $($ity: AtomicUsize::new(1),)* + }; + &COUNTERS + } + } + + // FIXME(eddyb) generate the definition of `HandleStore` in `server.rs`. + #[repr(C)] + #[allow(non_snake_case)] + pub(super) struct HandleStore<S: server::Types> { + $($oty: handle::OwnedStore<S::$oty>,)* + $($ity: handle::InternedStore<S::$ity>,)* + } + + impl<S: server::Types> HandleStore<S> { + pub(super) fn new(handle_counters: &'static HandleCounters) -> Self { + HandleStore { + $($oty: handle::OwnedStore::new(&handle_counters.$oty),)* + $($ity: handle::InternedStore::new(&handle_counters.$ity),)* + } + } + } + + $( + #[repr(C)] + pub(crate) struct $oty { + handle: handle::Handle, + // Prevent Send and Sync impls. `!Send`/`!Sync` is the usual + // way of doing this, but that requires unstable features. + // rust-analyzer uses this code and avoids unstable features. + _marker: PhantomData<*mut ()>, + } + + // Forward `Drop::drop` to the inherent `drop` method. + impl Drop for $oty { + fn drop(&mut self) { + $oty { + handle: self.handle, + _marker: PhantomData, + }.drop(); + } + } + + impl<S> Encode<S> for $oty { + fn encode(self, w: &mut Writer, s: &mut S) { + let handle = self.handle; + mem::forget(self); + handle.encode(w, s); + } + } + + impl<S: server::Types> DecodeMut<'_, '_, HandleStore<server::MarkedTypes<S>>> + for Marked<S::$oty, $oty> + { + fn decode(r: &mut Reader<'_>, s: &mut HandleStore<server::MarkedTypes<S>>) -> Self { + s.$oty.take(handle::Handle::decode(r, &mut ())) + } + } + + impl<S> Encode<S> for &$oty { + fn encode(self, w: &mut Writer, s: &mut S) { + self.handle.encode(w, s); + } + } + + impl<'s, S: server::Types> Decode<'_, 's, HandleStore<server::MarkedTypes<S>>> + for &'s Marked<S::$oty, $oty> + { + fn decode(r: &mut Reader<'_>, s: &'s HandleStore<server::MarkedTypes<S>>) -> Self { + &s.$oty[handle::Handle::decode(r, &mut ())] + } + } + + impl<S> Encode<S> for &mut $oty { + fn encode(self, w: &mut Writer, s: &mut S) { + self.handle.encode(w, s); + } + } + + impl<'s, S: server::Types> DecodeMut<'_, 's, HandleStore<server::MarkedTypes<S>>> + for &'s mut Marked<S::$oty, $oty> + { + fn decode( + r: &mut Reader<'_>, + s: &'s mut HandleStore<server::MarkedTypes<S>> + ) -> Self { + &mut s.$oty[handle::Handle::decode(r, &mut ())] + } + } + + impl<S: server::Types> Encode<HandleStore<server::MarkedTypes<S>>> + for Marked<S::$oty, $oty> + { + fn encode(self, w: &mut Writer, s: &mut HandleStore<server::MarkedTypes<S>>) { + s.$oty.alloc(self).encode(w, s); + } + } + + impl<S> DecodeMut<'_, '_, S> for $oty { + fn decode(r: &mut Reader<'_>, s: &mut S) -> Self { + $oty { + handle: handle::Handle::decode(r, s), + _marker: PhantomData, + } + } + } + )* + + $( + #[repr(C)] + #[derive(Copy, Clone, PartialEq, Eq, Hash)] + pub(crate) struct $ity { + handle: handle::Handle, + // Prevent Send and Sync impls. `!Send`/`!Sync` is the usual + // way of doing this, but that requires unstable features. + // rust-analyzer uses this code and avoids unstable features. + _marker: PhantomData<*mut ()>, + } + + impl<S> Encode<S> for $ity { + fn encode(self, w: &mut Writer, s: &mut S) { + self.handle.encode(w, s); + } + } + + impl<S: server::Types> DecodeMut<'_, '_, HandleStore<server::MarkedTypes<S>>> + for Marked<S::$ity, $ity> + { + fn decode(r: &mut Reader<'_>, s: &mut HandleStore<server::MarkedTypes<S>>) -> Self { + s.$ity.copy(handle::Handle::decode(r, &mut ())) + } + } + + impl<S: server::Types> Encode<HandleStore<server::MarkedTypes<S>>> + for Marked<S::$ity, $ity> + { + fn encode(self, w: &mut Writer, s: &mut HandleStore<server::MarkedTypes<S>>) { + s.$ity.alloc(self).encode(w, s); + } + } + + impl<S> DecodeMut<'_, '_, S> for $ity { + fn decode(r: &mut Reader<'_>, s: &mut S) -> Self { + $ity { + handle: handle::Handle::decode(r, s), + _marker: PhantomData, + } + } + } + )* + } +} +define_handles! { + 'owned: + FreeFunctions, + TokenStream, + Literal, + SourceFile, + MultiSpan, + Diagnostic, + + 'interned: + Ident, + Span, +} + +// FIXME(eddyb) generate these impls by pattern-matching on the +// names of methods - also could use the presence of `fn drop` +// to distinguish between 'owned and 'interned, above. +// Alternatively, special "modes" could be listed of types in with_api +// instead of pattern matching on methods, here and in server decl. + +impl Clone for TokenStream { + fn clone(&self) -> Self { + self.clone() + } +} + +impl Clone for Literal { + fn clone(&self) -> Self { + self.clone() + } +} + +impl fmt::Debug for Literal { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.debug_struct("Literal") + // format the kind without quotes, as in `kind: Float` + .field("kind", &format_args!("{}", &self.debug_kind())) + .field("symbol", &self.symbol()) + // format `Some("...")` on one line even in {:#?} mode + .field("suffix", &format_args!("{:?}", &self.suffix())) + .field("span", &self.span()) + .finish() + } +} + +impl Clone for SourceFile { + fn clone(&self) -> Self { + self.clone() + } +} + +impl Span { + pub(crate) fn def_site() -> Span { + Bridge::with(|bridge| bridge.globals.def_site) + } + + pub(crate) fn call_site() -> Span { + Bridge::with(|bridge| bridge.globals.call_site) + } + + pub(crate) fn mixed_site() -> Span { + Bridge::with(|bridge| bridge.globals.mixed_site) + } +} + +impl fmt::Debug for Span { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.write_str(&self.debug()) + } +} + +macro_rules! define_client_side { + ($($name:ident { + $(fn $method:ident($($arg:ident: $arg_ty:ty),* $(,)?) $(-> $ret_ty:ty)*;)* + }),* $(,)?) => { + $(impl $name { + $(pub(crate) fn $method($($arg: $arg_ty),*) $(-> $ret_ty)* { + Bridge::with(|bridge| { + let mut buf = bridge.cached_buffer.take(); + + buf.clear(); + api_tags::Method::$name(api_tags::$name::$method).encode(&mut buf, &mut ()); + reverse_encode!(buf; $($arg),*); + + buf = bridge.dispatch.call(buf); + + let r = Result::<_, PanicMessage>::decode(&mut &buf[..], &mut ()); + + bridge.cached_buffer = buf; + + r.unwrap_or_else(|e| panic::resume_unwind(e.into())) + }) + })* + })* + } +} +with_api!(self, self, define_client_side); + +struct Bridge<'a> { + /// Reusable buffer (only `clear`-ed, never shrunk), primarily + /// used for making requests. + cached_buffer: Buffer, + + /// Server-side function that the client uses to make requests. + dispatch: closure::Closure<'a, Buffer, Buffer>, + + /// Provided globals for this macro expansion. + globals: ExpnGlobals<Span>, +} + +enum BridgeState<'a> { + /// No server is currently connected to this client. + NotConnected, + + /// A server is connected and available for requests. + Connected(Bridge<'a>), + + /// Access to the bridge is being exclusively acquired + /// (e.g., during `BridgeState::with`). + InUse, +} + +enum BridgeStateL {} + +impl<'a> scoped_cell::ApplyL<'a> for BridgeStateL { + type Out = BridgeState<'a>; +} + +thread_local! { + static BRIDGE_STATE: scoped_cell::ScopedCell<BridgeStateL> = + scoped_cell::ScopedCell::new(BridgeState::NotConnected); +} + +impl BridgeState<'_> { + /// Take exclusive control of the thread-local + /// `BridgeState`, and pass it to `f`, mutably. + /// The state will be restored after `f` exits, even + /// by panic, including modifications made to it by `f`. + /// + /// N.B., while `f` is running, the thread-local state + /// is `BridgeState::InUse`. + fn with<R>(f: impl FnOnce(&mut BridgeState<'_>) -> R) -> R { + BRIDGE_STATE.with(|state| { + state.replace(BridgeState::InUse, |mut state| { + // FIXME(#52812) pass `f` directly to `replace` when `RefMutL` is gone + f(&mut *state) + }) + }) + } +} + +impl Bridge<'_> { + fn with<R>(f: impl FnOnce(&mut Bridge<'_>) -> R) -> R { + BridgeState::with(|state| match state { + BridgeState::NotConnected => { + panic!("procedural macro API is used outside of a procedural macro"); + } + BridgeState::InUse => { + panic!("procedural macro API is used while it's already in use"); + } + BridgeState::Connected(bridge) => f(bridge), + }) + } +} + +pub(crate) fn is_available() -> bool { + BridgeState::with(|state| match state { + BridgeState::Connected(_) | BridgeState::InUse => true, + BridgeState::NotConnected => false, + }) +} + +/// A client-side RPC entry-point, which may be using a different `proc_macro` +/// from the one used by the server, but can be invoked compatibly. +/// +/// Note that the (phantom) `I` ("input") and `O` ("output") type parameters +/// decorate the `Client<I, O>` with the RPC "interface" of the entry-point, but +/// do not themselves participate in ABI, at all, only facilitate type-checking. +/// +/// E.g. `Client<TokenStream, TokenStream>` is the common proc macro interface, +/// used for `#[proc_macro] fn foo(input: TokenStream) -> TokenStream`, +/// indicating that the RPC input and output will be serialized token streams, +/// and forcing the use of APIs that take/return `S::TokenStream`, server-side. +#[repr(C)] +pub struct Client<I, O> { + // FIXME(eddyb) use a reference to the `static COUNTERS`, instead of + // a wrapper `fn` pointer, once `const fn` can reference `static`s. + pub(super) get_handle_counters: extern "C" fn() -> &'static HandleCounters, + + pub(super) run: extern "C" fn(BridgeConfig<'_>) -> Buffer, + + pub(super) _marker: PhantomData<fn(I) -> O>, +} + +impl<I, O> Copy for Client<I, O> {} +impl<I, O> Clone for Client<I, O> { + fn clone(&self) -> Self { + *self + } +} + +fn maybe_install_panic_hook(force_show_panics: bool) { + // Hide the default panic output within `proc_macro` expansions. + // NB. the server can't do this because it may use a different libstd. + static HIDE_PANICS_DURING_EXPANSION: Once = Once::new(); + HIDE_PANICS_DURING_EXPANSION.call_once(|| { + let prev = panic::take_hook(); + panic::set_hook(Box::new(move |info| { + let show = BridgeState::with(|state| match state { + BridgeState::NotConnected => true, + BridgeState::Connected(_) | BridgeState::InUse => force_show_panics, + }); + if show { + prev(info) + } + })); + }); +} + +/// Client-side helper for handling client panics, entering the bridge, +/// deserializing input and serializing output. +// FIXME(eddyb) maybe replace `Bridge::enter` with this? +fn run_client<A: for<'a, 's> DecodeMut<'a, 's, ()>, R: Encode<()>>( + config: BridgeConfig<'_>, + f: impl FnOnce(A) -> R, +) -> Buffer { + let BridgeConfig { input: mut buf, dispatch, force_show_panics, .. } = config; + + panic::catch_unwind(panic::AssertUnwindSafe(|| { + maybe_install_panic_hook(force_show_panics); + + let reader = &mut &buf[..]; + let (globals, input) = <(ExpnGlobals<Span>, A)>::decode(reader, &mut ()); + + // Put the buffer we used for input back in the `Bridge` for requests. + let new_state = + BridgeState::Connected(Bridge { cached_buffer: buf.take(), dispatch, globals }); + + BRIDGE_STATE.with(|state| { + state.set(new_state, || { + let output = f(input); + + // Take the `cached_buffer` back out, for the output value. + buf = Bridge::with(|bridge| bridge.cached_buffer.take()); + + // HACK(eddyb) Separate encoding a success value (`Ok(output)`) + // from encoding a panic (`Err(e: PanicMessage)`) to avoid + // having handles outside the `bridge.enter(|| ...)` scope, and + // to catch panics that could happen while encoding the success. + // + // Note that panics should be impossible beyond this point, but + // this is defensively trying to avoid any accidental panicking + // reaching the `extern "C"` (which should `abort` but might not + // at the moment, so this is also potentially preventing UB). + buf.clear(); + Ok::<_, ()>(output).encode(&mut buf, &mut ()); + }) + }) + })) + .map_err(PanicMessage::from) + .unwrap_or_else(|e| { + buf.clear(); + Err::<(), _>(e).encode(&mut buf, &mut ()); + }); + buf +} + +impl Client<super::super::TokenStream, super::super::TokenStream> { + pub const fn expand1( + f: impl Fn(super::super::TokenStream) -> super::super::TokenStream + Copy, + ) -> Self { + Client { + get_handle_counters: HandleCounters::get, + run: super::selfless_reify::reify_to_extern_c_fn_hrt_bridge(move |bridge| { + run_client(bridge, |input| f(super::super::TokenStream(input)).0) + }), + _marker: PhantomData, + } + } +} + +impl Client<(super::super::TokenStream, super::super::TokenStream), super::super::TokenStream> { + pub const fn expand2( + f: impl Fn(super::super::TokenStream, super::super::TokenStream) -> super::super::TokenStream + + Copy, + ) -> Self { + Client { + get_handle_counters: HandleCounters::get, + run: super::selfless_reify::reify_to_extern_c_fn_hrt_bridge(move |bridge| { + run_client(bridge, |(input, input2)| { + f(super::super::TokenStream(input), super::super::TokenStream(input2)).0 + }) + }), + _marker: PhantomData, + } + } +} + +#[repr(C)] +#[derive(Copy, Clone)] +pub enum ProcMacro { + CustomDerive { + trait_name: &'static str, + attributes: &'static [&'static str], + client: Client<super::super::TokenStream, super::super::TokenStream>, + }, + + Attr { + name: &'static str, + client: Client< + (super::super::TokenStream, super::super::TokenStream), + super::super::TokenStream, + >, + }, + + Bang { + name: &'static str, + client: Client<super::super::TokenStream, super::super::TokenStream>, + }, +} + +impl ProcMacro { + pub fn name(&self) -> &'static str { + match self { + ProcMacro::CustomDerive { trait_name, .. } => trait_name, + ProcMacro::Attr { name, .. } => name, + ProcMacro::Bang { name, .. } => name, + } + } + + pub const fn custom_derive( + trait_name: &'static str, + attributes: &'static [&'static str], + expand: impl Fn(super::super::TokenStream) -> super::super::TokenStream + Copy, + ) -> Self { + ProcMacro::CustomDerive { trait_name, attributes, client: Client::expand1(expand) } + } + + pub const fn attr( + name: &'static str, + expand: impl Fn(super::super::TokenStream, super::super::TokenStream) -> super::super::TokenStream + + Copy, + ) -> Self { + ProcMacro::Attr { name, client: Client::expand2(expand) } + } + + pub const fn bang( + name: &'static str, + expand: impl Fn(super::super::TokenStream) -> super::super::TokenStream + Copy, + ) -> Self { + ProcMacro::Bang { name, client: Client::expand1(expand) } + } +} |