binder: add async Rust support
Test: add and run integration tests
Change-Id: I7671eeb7dfe4cc45efd57756753b361440529a3c
diff --git a/libs/binder/rust/Android.bp b/libs/binder/rust/Android.bp
index ecb044e..d323022 100644
--- a/libs/binder/rust/Android.bp
+++ b/libs/binder/rust/Android.bp
@@ -33,6 +33,27 @@
}
rust_library {
+ name: "libbinder_tokio_rs",
+ crate_name: "binder_tokio",
+ srcs: ["binder_tokio/lib.rs"],
+ rustlibs: [
+ "libbinder_rs",
+ "libtokio",
+ ],
+ host_supported: true,
+ target: {
+ darwin: {
+ enabled: false,
+ }
+ },
+ apex_available: [
+ "//apex_available:platform",
+ "com.android.compos",
+ "com.android.virt",
+ ],
+}
+
+rust_library {
name: "libbinder_ndk_sys",
crate_name: "binder_ndk_sys",
srcs: [
diff --git a/libs/binder/rust/binder_tokio/lib.rs b/libs/binder/rust/binder_tokio/lib.rs
new file mode 100644
index 0000000..a71ddda
--- /dev/null
+++ b/libs/binder/rust/binder_tokio/lib.rs
@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+//! This crate lets you use the Tokio `spawn_blocking` pool with AIDL in async
+//! Rust code.
+//!
+//! This crate works by defining a type [`Tokio`], which you can use as the
+//! generic parameter in the async version of the trait generated by the AIDL
+//! compiler.
+//! ```text
+//! use binder_tokio::Tokio;
+//!
+//! binder::get_interface::<dyn SomeAsyncInterface<Tokio>>("...").
+//! ```
+//!
+//! [`Tokio`]: crate::Tokio
+
+use binder::public_api::{BinderAsyncPool, BoxFuture};
+use binder::StatusCode;
+use std::future::Future;
+
+/// Use the Tokio `spawn_blocking` pool with AIDL.
+pub enum Tokio {}
+
+impl BinderAsyncPool for Tokio {
+ fn spawn<'a, F1, F2, Fut, A, B, E>(spawn_me: F1, after_spawn: F2) -> BoxFuture<'a, Result<B, E>>
+ where
+ F1: FnOnce() -> A,
+ F2: FnOnce(A) -> Fut,
+ Fut: Future<Output = Result<B, E>>,
+ F1: Send + 'static,
+ F2: Send + 'a,
+ Fut: Send + 'a,
+ A: Send + 'static,
+ B: Send + 'a,
+ E: From<crate::StatusCode>,
+ {
+ let handle = tokio::task::spawn_blocking(spawn_me);
+ Box::pin(async move {
+ // The `is_panic` branch is not actually reachable in Android as we compile
+ // with `panic = abort`.
+ match handle.await {
+ Ok(res) => after_spawn(res).await,
+ Err(e) if e.is_panic() => std::panic::resume_unwind(e.into_panic()),
+ Err(e) if e.is_cancelled() => Err(StatusCode::FAILED_TRANSACTION.into()),
+ Err(_) => Err(StatusCode::UNKNOWN_ERROR.into()),
+ }
+ })
+ }
+}
+
+
diff --git a/libs/binder/rust/src/binder.rs b/libs/binder/rust/src/binder.rs
index cc5dd06..4e048d7 100644
--- a/libs/binder/rust/src/binder.rs
+++ b/libs/binder/rust/src/binder.rs
@@ -713,12 +713,14 @@
$interface:path[$descriptor:expr] {
native: $native:ident($on_transact:path),
proxy: $proxy:ident,
+ $(async: $async_interface:ident,)?
}
} => {
$crate::declare_binder_interface! {
$interface[$descriptor] {
native: $native($on_transact),
proxy: $proxy {},
+ $(async: $async_interface,)?
stability: $crate::Stability::default(),
}
}
@@ -728,6 +730,7 @@
$interface:path[$descriptor:expr] {
native: $native:ident($on_transact:path),
proxy: $proxy:ident,
+ $(async: $async_interface:ident,)?
stability: $stability:expr,
}
} => {
@@ -735,6 +738,7 @@
$interface[$descriptor] {
native: $native($on_transact),
proxy: $proxy {},
+ $(async: $async_interface,)?
stability: $stability,
}
}
@@ -746,6 +750,7 @@
proxy: $proxy:ident {
$($fname:ident: $fty:ty = $finit:expr),*
},
+ $(async: $async_interface:ident,)?
}
} => {
$crate::declare_binder_interface! {
@@ -754,6 +759,7 @@
proxy: $proxy {
$($fname: $fty = $finit),*
},
+ $(async: $async_interface,)?
stability: $crate::Stability::default(),
}
}
@@ -765,6 +771,7 @@
proxy: $proxy:ident {
$($fname:ident: $fty:ty = $finit:expr),*
},
+ $(async: $async_interface:ident,)?
stability: $stability:expr,
}
} => {
@@ -776,6 +783,7 @@
proxy: $proxy {
$($fname: $fty = $finit),*
},
+ $(async: $async_interface,)?
stability: $stability,
}
}
@@ -791,6 +799,8 @@
$($fname:ident: $fty:ty = $finit:expr),*
},
+ $( async: $async_interface:ident, )?
+
stability: $stability:expr,
}
} => {
@@ -924,7 +934,7 @@
}
}
- impl std::fmt::Debug for dyn $interface {
+ impl std::fmt::Debug for dyn $interface + '_ {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
f.pad(stringify!($interface))
}
@@ -938,6 +948,73 @@
.expect(concat!("Error cloning interface ", stringify!($interface)))
}
}
+
+ $(
+ // Async interface trait implementations.
+ impl<P: $crate::BinderAsyncPool> $crate::FromIBinder for dyn $async_interface<P> {
+ fn try_from(mut ibinder: $crate::SpIBinder) -> $crate::Result<$crate::Strong<dyn $async_interface<P>>> {
+ use $crate::AssociateClass;
+
+ let existing_class = ibinder.get_class();
+ if let Some(class) = existing_class {
+ if class != <$native as $crate::Remotable>::get_class() &&
+ class.get_descriptor() == <$native as $crate::Remotable>::get_descriptor()
+ {
+ // The binder object's descriptor string matches what we
+ // expect. We still need to treat this local or already
+ // associated object as remote, because we can't cast it
+ // into a Rust service object without a matching class
+ // pointer.
+ return Ok($crate::Strong::new(Box::new(<$proxy as $crate::Proxy>::from_binder(ibinder)?)));
+ }
+ }
+
+ if ibinder.associate_class(<$native as $crate::Remotable>::get_class()) {
+ let service: $crate::Result<$crate::Binder<$native>> =
+ std::convert::TryFrom::try_from(ibinder.clone());
+ if let Ok(service) = service {
+ // We were able to associate with our expected class and
+ // the service is local.
+ todo!()
+ //return Ok($crate::Strong::new(Box::new(service)));
+ } else {
+ // Service is remote
+ return Ok($crate::Strong::new(Box::new(<$proxy as $crate::Proxy>::from_binder(ibinder)?)));
+ }
+ }
+
+ Err($crate::StatusCode::BAD_TYPE.into())
+ }
+ }
+
+ impl<P: $crate::BinderAsyncPool> $crate::parcel::Serialize for dyn $async_interface<P> + '_ {
+ fn serialize(&self, parcel: &mut $crate::parcel::Parcel) -> $crate::Result<()> {
+ let binder = $crate::Interface::as_binder(self);
+ parcel.write(&binder)
+ }
+ }
+
+ impl<P: $crate::BinderAsyncPool> $crate::parcel::SerializeOption for dyn $async_interface<P> + '_ {
+ fn serialize_option(this: Option<&Self>, parcel: &mut $crate::parcel::Parcel) -> $crate::Result<()> {
+ parcel.write(&this.map($crate::Interface::as_binder))
+ }
+ }
+
+ impl<P: $crate::BinderAsyncPool> std::fmt::Debug for dyn $async_interface<P> + '_ {
+ fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+ f.pad(stringify!($async_interface))
+ }
+ }
+
+ /// Convert a &dyn $async_interface to Strong<dyn $async_interface>
+ impl<P: $crate::BinderAsyncPool> std::borrow::ToOwned for dyn $async_interface<P> {
+ type Owned = $crate::Strong<dyn $async_interface<P>>;
+ fn to_owned(&self) -> Self::Owned {
+ self.as_binder().into_interface()
+ .expect(concat!("Error cloning interface ", stringify!($async_interface)))
+ }
+ }
+ )?
};
}
diff --git a/libs/binder/rust/src/binder_async.rs b/libs/binder/rust/src/binder_async.rs
new file mode 100644
index 0000000..214c0b5
--- /dev/null
+++ b/libs/binder/rust/src/binder_async.rs
@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+use std::future::Future;
+use std::pin::Pin;
+
+/// A type alias for a pinned, boxed future that lets you write shorter code without littering it
+/// with Pin and Send bounds.
+pub type BoxFuture<'a, T> = Pin<Box<dyn Future<Output = T> + Send + 'a>>;
+
+/// A thread pool for running binder transactions.
+pub trait BinderAsyncPool {
+ /// This function should conceptually behave like this:
+ ///
+ /// ```text
+ /// let result = spawn_thread(|| spawn_me()).await;
+ /// return after_spawn(result).await;
+ /// ```
+ ///
+ /// If the spawning fails for some reason, the method may also skip the `after_spawn` closure
+ /// and immediately return an error.
+ ///
+ /// The only difference between different implementations should be which
+ /// `spawn_thread` method is used. For Tokio, it would be `tokio::task::spawn_blocking`.
+ ///
+ /// This method has the design it has because the only way to define a trait that
+ /// allows the return type of the spawn to be chosen by the caller is to return a
+ /// boxed `Future` trait object, and including `after_spawn` in the trait function
+ /// allows the caller to avoid double-boxing if they want to do anything to the value
+ /// returned from the spawned thread.
+ fn spawn<'a, F1, F2, Fut, A, B, E>(spawn_me: F1, after_spawn: F2) -> BoxFuture<'a, Result<B, E>>
+ where
+ F1: FnOnce() -> A,
+ F2: FnOnce(A) -> Fut,
+ Fut: Future<Output = Result<B, E>>,
+ F1: Send + 'static,
+ F2: Send + 'a,
+ Fut: Send + 'a,
+ A: Send + 'static,
+ B: Send + 'a,
+ E: From<crate::StatusCode>;
+}
diff --git a/libs/binder/rust/src/lib.rs b/libs/binder/rust/src/lib.rs
index 81b620e..2ac2d2f 100644
--- a/libs/binder/rust/src/lib.rs
+++ b/libs/binder/rust/src/lib.rs
@@ -98,6 +98,7 @@
#[macro_use]
mod binder;
+mod binder_async;
mod error;
mod native;
mod state;
@@ -111,6 +112,7 @@
Stability, Strong, TransactionCode, TransactionFlags, Weak, FIRST_CALL_TRANSACTION,
FLAG_CLEAR_BUF, FLAG_ONEWAY, FLAG_PRIVATE_LOCAL, LAST_CALL_TRANSACTION,
};
+pub use crate::binder_async::{BoxFuture, BinderAsyncPool};
pub use error::{status_t, ExceptionCode, Result, Status, StatusCode};
pub use native::{add_service, force_lazy_services_persist, register_lazy_service, Binder};
pub use parcel::{OwnedParcel, Parcel};
@@ -133,8 +135,9 @@
wait_for_interface,
};
pub use super::{
- BinderFeatures, DeathRecipient, ExceptionCode, IBinder, Interface, ProcessState, SpIBinder,
- Status, StatusCode, Strong, ThreadState, Weak, WpIBinder,
+ BinderAsyncPool, BinderFeatures, BoxFuture, DeathRecipient, ExceptionCode, IBinder,
+ Interface, ProcessState, SpIBinder, Status, StatusCode, Strong, ThreadState, Weak,
+ WpIBinder,
};
/// Binder result containing a [`Status`] on error.
diff --git a/libs/binder/rust/src/parcel.rs b/libs/binder/rust/src/parcel.rs
index 9dba950..a0e1478 100644
--- a/libs/binder/rust/src/parcel.rs
+++ b/libs/binder/rust/src/parcel.rs
@@ -83,6 +83,19 @@
Self { ptr }
}
+ /// Convert the provided parcel to an owned parcel, or return `None` if it
+ /// is borrowed.
+ pub fn try_from(parcel: Parcel) -> Option<OwnedParcel> {
+ match &parcel {
+ Parcel::Owned(ptr) => {
+ let ptr = *ptr;
+ std::mem::forget(parcel);
+ Some(OwnedParcel { ptr })
+ }
+ Parcel::Borrowed(_) => None,
+ }
+ }
+
/// Create an owned reference to a parcel object from a raw pointer.
///
/// # Safety
diff --git a/libs/binder/rust/tests/Android.bp b/libs/binder/rust/tests/Android.bp
index ecc61f4..2d1175b 100644
--- a/libs/binder/rust/tests/Android.bp
+++ b/libs/binder/rust/tests/Android.bp
@@ -13,6 +13,8 @@
rustlibs: [
"libbinder_rs",
"libselinux_bindgen",
+ "libbinder_tokio_rs",
+ "libtokio",
],
shared_libs: [
"libselinux",
diff --git a/libs/binder/rust/tests/integration.rs b/libs/binder/rust/tests/integration.rs
index 335e8d8..3c29073 100644
--- a/libs/binder/rust/tests/integration.rs
+++ b/libs/binder/rust/tests/integration.rs
@@ -17,7 +17,7 @@
//! Rust Binder crate integration tests
use binder::declare_binder_interface;
-use binder::parcel::Parcel;
+use binder::parcel::{Parcel, OwnedParcel};
use binder::{
Binder, BinderFeatures, IBinderInternal, Interface, StatusCode, ThreadState, TransactionCode,
FIRST_CALL_TRANSACTION,
@@ -154,12 +154,25 @@
fn get_selinux_context(&self) -> binder::Result<String>;
}
+/// Async trivial testing binder interface
+pub trait IATest<P>: Interface {
+ /// Returns a test string
+ fn test(&self) -> binder::BoxFuture<'static, binder::Result<String>>;
+
+ /// Return the arguments sent via dump
+ fn get_dump_args(&self) -> binder::BoxFuture<'static, binder::Result<Vec<String>>>;
+
+ /// Returns the caller's SELinux context
+ fn get_selinux_context(&self) -> binder::BoxFuture<'static, binder::Result<String>>;
+}
+
declare_binder_interface! {
ITest["android.os.ITest"] {
native: BnTest(on_transact),
proxy: BpTest {
x: i32 = 100
},
+ async: IATest,
}
}
@@ -201,6 +214,32 @@
}
}
+impl<P: binder::BinderAsyncPool> IATest<P> for BpTest {
+ fn test(&self) -> binder::BoxFuture<'static, binder::Result<String>> {
+ let binder = self.binder.clone();
+ P::spawn(
+ move || binder.transact(TestTransactionCode::Test as TransactionCode, 0, |_| Ok(())).map(|p| OwnedParcel::try_from(p).unwrap()),
+ |reply| async move { reply?.into_parcel().read() }
+ )
+ }
+
+ fn get_dump_args(&self) -> binder::BoxFuture<'static, binder::Result<Vec<String>>> {
+ let binder = self.binder.clone();
+ P::spawn(
+ move || binder.transact(TestTransactionCode::GetDumpArgs as TransactionCode, 0, |_| Ok(())).map(|p| OwnedParcel::try_from(p).unwrap()),
+ |reply| async move { reply?.into_parcel().read() }
+ )
+ }
+
+ fn get_selinux_context(&self) -> binder::BoxFuture<'static, binder::Result<String>> {
+ let binder = self.binder.clone();
+ P::spawn(
+ move || binder.transact(TestTransactionCode::GetSelinuxContext as TransactionCode, 0, |_| Ok(())).map(|p| OwnedParcel::try_from(p).unwrap()),
+ |reply| async move { reply?.into_parcel().read() }
+ )
+ }
+}
+
impl ITest for Binder<BnTest> {
fn test(&self) -> binder::Result<String> {
self.0.test()
@@ -215,6 +254,23 @@
}
}
+impl<P: binder::BinderAsyncPool> IATest<P> for Binder<BnTest> {
+ fn test(&self) -> binder::BoxFuture<'static, binder::Result<String>> {
+ let res = self.0.test();
+ Box::pin(async move { res })
+ }
+
+ fn get_dump_args(&self) -> binder::BoxFuture<'static, binder::Result<Vec<String>>> {
+ let res = self.0.get_dump_args();
+ Box::pin(async move { res })
+ }
+
+ fn get_selinux_context(&self) -> binder::BoxFuture<'static, binder::Result<String>> {
+ let res = self.0.get_selinux_context();
+ Box::pin(async move { res })
+ }
+}
+
/// Trivial testing binder interface
pub trait ITestSameDescriptor: Interface {}
@@ -255,7 +311,9 @@
SpIBinder, StatusCode, Strong,
};
- use super::{BnTest, ITest, ITestSameDescriptor, TestService, RUST_SERVICE_BINARY};
+ use binder_tokio::Tokio;
+
+ use super::{BnTest, ITest, IATest, ITestSameDescriptor, TestService, RUST_SERVICE_BINARY};
pub struct ScopedServiceProcess(Child);
@@ -303,12 +361,20 @@
binder::get_interface::<dyn ITest>("this_service_does_not_exist").err(),
Some(StatusCode::NAME_NOT_FOUND)
);
+ assert_eq!(
+ binder::get_interface::<dyn IATest<Tokio>>("this_service_does_not_exist").err(),
+ Some(StatusCode::NAME_NOT_FOUND)
+ );
// The service manager service isn't an ITest, so this must fail.
assert_eq!(
binder::get_interface::<dyn ITest>("manager").err(),
Some(StatusCode::BAD_TYPE)
);
+ assert_eq!(
+ binder::get_interface::<dyn IATest<Tokio>>("manager").err(),
+ Some(StatusCode::BAD_TYPE)
+ );
}
#[test]
@@ -323,6 +389,10 @@
binder::wait_for_interface::<dyn ITest>("manager").err(),
Some(StatusCode::BAD_TYPE)
);
+ assert_eq!(
+ binder::wait_for_interface::<dyn IATest<Tokio>>("manager").err(),
+ Some(StatusCode::BAD_TYPE)
+ );
}
#[test]
@@ -334,6 +404,15 @@
assert_eq!(test_client.test().unwrap(), "trivial_client_test");
}
+ #[tokio::test]
+ async fn trivial_client_async() {
+ let service_name = "trivial_client_test";
+ let _process = ScopedServiceProcess::new(service_name);
+ let test_client: Strong<dyn IATest<Tokio>> =
+ binder::get_interface(service_name).expect("Did not get manager binder service");
+ assert_eq!(test_client.test().await.unwrap(), "trivial_client_test");
+ }
+
#[test]
fn wait_for_trivial_client() {
let service_name = "wait_for_trivial_client_test";
@@ -343,23 +422,47 @@
assert_eq!(test_client.test().unwrap(), "wait_for_trivial_client_test");
}
+ #[tokio::test]
+ async fn wait_for_trivial_client_async() {
+ let service_name = "wait_for_trivial_client_test";
+ let _process = ScopedServiceProcess::new(service_name);
+ let test_client: Strong<dyn IATest<Tokio>> =
+ binder::wait_for_interface(service_name).expect("Did not get manager binder service");
+ assert_eq!(test_client.test().await.unwrap(), "wait_for_trivial_client_test");
+ }
+
+ fn get_expected_selinux_context() -> &'static str {
+ unsafe {
+ let mut out_ptr = ptr::null_mut();
+ assert_eq!(selinux_sys::getcon(&mut out_ptr), 0);
+ assert!(!out_ptr.is_null());
+ CStr::from_ptr(out_ptr)
+ .to_str()
+ .expect("context was invalid UTF-8")
+ }
+ }
+
#[test]
fn get_selinux_context() {
let service_name = "get_selinux_context";
let _process = ScopedServiceProcess::new(service_name);
let test_client: Strong<dyn ITest> =
binder::get_interface(service_name).expect("Did not get manager binder service");
- let expected_context = unsafe {
- let mut out_ptr = ptr::null_mut();
- assert_eq!(selinux_sys::getcon(&mut out_ptr), 0);
- assert!(!out_ptr.is_null());
- CStr::from_ptr(out_ptr)
- };
assert_eq!(
test_client.get_selinux_context().unwrap(),
- expected_context
- .to_str()
- .expect("context was invalid UTF-8"),
+ get_expected_selinux_context()
+ );
+ }
+
+ #[tokio::test]
+ async fn get_selinux_context_async() {
+ let service_name = "get_selinux_context";
+ let _process = ScopedServiceProcess::new(service_name);
+ let test_client: Strong<dyn IATest<Tokio>> =
+ binder::get_interface(service_name).expect("Did not get manager binder service");
+ assert_eq!(
+ test_client.get_selinux_context().await.unwrap(),
+ get_expected_selinux_context()
);
}