diff options
| -rw-r--r-- | src/libproc_macro/bridge/client.rs | 71 |
1 files changed, 23 insertions, 48 deletions
diff --git a/src/libproc_macro/bridge/client.rs b/src/libproc_macro/bridge/client.rs index cd33c4bc67e..b17359a4c8c 100644 --- a/src/libproc_macro/bridge/client.rs +++ b/src/libproc_macro/bridge/client.rs @@ -341,9 +341,12 @@ pub struct Client<F> { 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(); @@ -351,12 +354,12 @@ extern "C" fn run_expand1( 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()); @@ -384,63 +387,35 @@ extern "C" fn run_expand1( impl Client<fn(crate::TokenStream) -> crate::TokenStream> { pub const fn expand1(f: fn(crate::TokenStream) -> crate::TokenStream) -> Self { + extern "C" fn run( + bridge: Bridge<'_>, + f: fn(crate::TokenStream) -> crate::TokenStream, + ) -> Buffer<u8> { + run_client(bridge, |input| f(crate::TokenStream(input)).0) + } Client { get_handle_counters: HandleCounters::get, - run: run_expand1, + 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 ) -> Self { + extern "C" fn run( + bridge: Bridge<'_>, + f: fn(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: run_expand2, + run, f, } } |