pub(super) f: F,
}
-extern "C" fn run_expand1(
+/// 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<()>>(
mut bridge: Bridge<'_>,
- f: fn(crate::TokenStream) -> crate::TokenStream,
+ f: impl FnOnce(A) -> R,
) -> Buffer<u8> {
// The initial `cached_buffer` contains the input.
let mut b = bridge.cached_buffer.take();
panic::catch_unwind(panic::AssertUnwindSafe(|| {
bridge.enter(|| {
let reader = &mut &b[..];
- let input = TokenStream::decode(reader, &mut ());
+ let input = A::decode(reader, &mut ());
// Put the `cached_buffer` back in the `Bridge`, for requests.
Bridge::with(|bridge| bridge.cached_buffer = b.take());
- let output = f(crate::TokenStream(input)).0;
+ let output = f(input);
// Take the `cached_buffer` back out, for the output value.
b = Bridge::with(|bridge| bridge.cached_buffer.take());
impl Client<fn(crate::TokenStream) -> crate::TokenStream> {
pub const fn expand1(f: fn(crate::TokenStream) -> crate::TokenStream) -> Self {
- Client {
- get_handle_counters: HandleCounters::get,
- run: run_expand1,
- f,
+ extern "C" fn run(
+ bridge: Bridge<'_>,
+ f: impl FnOnce(crate::TokenStream) -> crate::TokenStream,
+ ) -> Buffer<u8> {
+ run_client(bridge, |input| f(crate::TokenStream(input)).0)
}
+ Client { get_handle_counters: HandleCounters::get, run, f }
}
}
-extern "C" fn run_expand2(
- mut bridge: Bridge<'_>,
- f: fn(crate::TokenStream, crate::TokenStream) -> crate::TokenStream,
-) -> Buffer<u8> {
- // The initial `cached_buffer` contains the input.
- let mut b = bridge.cached_buffer.take();
-
- panic::catch_unwind(panic::AssertUnwindSafe(|| {
- bridge.enter(|| {
- let reader = &mut &b[..];
- let input = TokenStream::decode(reader, &mut ());
- let input2 = TokenStream::decode(reader, &mut ());
-
- // Put the `cached_buffer` back in the `Bridge`, for requests.
- Bridge::with(|bridge| bridge.cached_buffer = b.take());
-
- let output = f(crate::TokenStream(input), crate::TokenStream(input2)).0;
-
- // Take the `cached_buffer` back out, for the output value.
- b = 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 may not
- // at the moment, so this is also potentially preventing UB).
- b.clear();
- Ok::<_, ()>(output).encode(&mut b, &mut ());
- })
- }))
- .map_err(PanicMessage::from)
- .unwrap_or_else(|e| {
- b.clear();
- Err::<(), _>(e).encode(&mut b, &mut ());
- });
- b
-}
-
impl Client<fn(crate::TokenStream, crate::TokenStream) -> crate::TokenStream> {
pub const fn expand2(
- f: fn(crate::TokenStream, crate::TokenStream) -> crate::TokenStream
+ f: fn(crate::TokenStream, crate::TokenStream) -> crate::TokenStream,
) -> Self {
- Client {
- get_handle_counters: HandleCounters::get,
- run: run_expand2,
- f,
+ extern "C" fn run(
+ bridge: Bridge<'_>,
+ f: impl FnOnce(crate::TokenStream, crate::TokenStream) -> crate::TokenStream,
+ ) -> Buffer<u8> {
+ run_client(bridge, |(input, input2)| {
+ f(crate::TokenStream(input), crate::TokenStream(input2)).0
+ })
}
+ Client { get_handle_counters: HandleCounters::get, run, f }
}
}
match self {
ProcMacro::CustomDerive { trait_name, .. } => trait_name,
ProcMacro::Attr { name, .. } => name,
- ProcMacro::Bang { name, ..} => name
+ ProcMacro::Bang { name, .. } => name,
}
}
attributes: &'static [&'static str],
expand: fn(crate::TokenStream) -> crate::TokenStream,
) -> Self {
- ProcMacro::CustomDerive {
- trait_name,
- attributes,
- client: Client::expand1(expand),
- }
+ ProcMacro::CustomDerive { trait_name, attributes, client: Client::expand1(expand) }
}
pub const fn attr(
name: &'static str,
expand: fn(crate::TokenStream, crate::TokenStream) -> crate::TokenStream,
) -> Self {
- ProcMacro::Attr {
- name,
- client: Client::expand2(expand),
- }
+ ProcMacro::Attr { name, client: Client::expand2(expand) }
}
pub const fn bang(
name: &'static str,
- expand: fn(crate::TokenStream) -> crate::TokenStream
+ expand: fn(crate::TokenStream) -> crate::TokenStream,
) -> Self {
- ProcMacro::Bang {
- name,
- client: Client::expand1(expand),
- }
+ ProcMacro::Bang { name, client: Client::expand1(expand) }
}
}