binder_rs: add OwnedParcel
This adds a new binder::OwnedParcel type that exclusively
contains an owned parcel, and implements Send so it
can be sent between threads. Parcel cannot implement Send
because Parcel::Borrowed could point to thread-local
C++ values, e.g., a Parcel stored on the stack.
This change is a prerequisite for both async and
thread-safe ParcelableHolder.
Bug: 200676345
Test: atest aidl_integration_test
Change-Id: I1a7b965d26cb5350576450debd7d058a6451b1f0
diff --git a/libs/binder/rust/src/binder.rs b/libs/binder/rust/src/binder.rs
index 854b1f9..cc5dd06 100644
--- a/libs/binder/rust/src/binder.rs
+++ b/libs/binder/rust/src/binder.rs
@@ -17,7 +17,7 @@
//! Trait definitions for binder objects
use crate::error::{status_t, Result, StatusCode};
-use crate::parcel::Parcel;
+use crate::parcel::{OwnedParcel, Parcel};
use crate::proxy::{DeathRecipient, SpIBinder, WpIBinder};
use crate::sys;
@@ -177,25 +177,25 @@
fn get_extension(&mut self) -> Result<Option<SpIBinder>>;
/// Create a Parcel that can be used with `submit_transact`.
- fn prepare_transact(&self) -> Result<Parcel>;
+ fn prepare_transact(&self) -> Result<OwnedParcel>;
/// Perform a generic operation with the object.
///
- /// The provided [`Parcel`] must have been created by a call to
+ /// The provided [`OwnedParcel`] must have been created by a call to
/// `prepare_transact` on the same binder.
///
/// # Arguments
///
/// * `code` - Transaction code for the operation.
- /// * `data` - [`Parcel`] with input data.
+ /// * `data` - [`OwnedParcel`] with input data.
/// * `flags` - Transaction flags, e.g. marking the transaction as
/// asynchronous ([`FLAG_ONEWAY`](FLAG_ONEWAY)).
fn submit_transact(
&self,
code: TransactionCode,
- data: Parcel,
+ data: OwnedParcel,
flags: TransactionFlags,
- ) -> Result<Parcel>;
+ ) -> Result<OwnedParcel>;
/// Perform a generic operation with the object. This is a convenience
/// method that internally calls `prepare_transact` followed by
@@ -213,8 +213,8 @@
input_callback: F,
) -> Result<Parcel> {
let mut parcel = self.prepare_transact()?;
- input_callback(&mut parcel)?;
- self.submit_transact(code, parcel, flags)
+ input_callback(&mut parcel.borrowed())?;
+ self.submit_transact(code, parcel, flags).map(OwnedParcel::into_parcel)
}
}