[Private GATT] Add support for GATT write requests (8cab37dc) · Commits · e / os / android_packages_modules_Bluetooth

system/rust/src/gatt/callbacks.rs

+23 −1

Original line number	Diff line number	Diff line
		@@ -8,7 +8,7 @@ pub use callback_transaction_manager::{CallbackResponseError, CallbackTransactio

		use async_trait::async_trait;

		use crate::packets::{AttAttributeDataChild, AttErrorCode};
		use crate::packets::{AttAttributeDataChild, AttAttributeDataView, AttErrorCode};

		use super::ids::{AttHandle, ConnectionId, TransactionId};

		@@ -25,6 +25,20 @@ pub trait GattCallbacks {
		offset: u32,
		is_long: bool,
		);

		/// Invoked when a client tries to write a characteristic. Expects a
		/// response using bluetooth::gatt::send_response();
		#[allow(clippy::too_many_arguments)] // needed to match the C++ interface
		fn on_server_write_characteristic(
		&self,
		conn_id: ConnectionId,
		trans_id: TransactionId,
		handle: AttHandle,
		offset: u32,
		need_response: bool,
		is_prepare: bool,
		value: AttAttributeDataView,
		);
		}

		/// This interface is an "async" version of the above, and is passed directly
		@@ -44,4 +58,12 @@ pub trait GattDatastore {
		conn_id: ConnectionId,
		handle: AttHandle,
		) -> Result<AttAttributeDataChild, AttErrorCode>;

		/// Write data to a given characteristic on the specified connection.
		async fn write_characteristic(
		&self,
		conn_id: ConnectionId,
		handle: AttHandle,
		data: AttAttributeDataView<'_>,
		) -> Result<(), AttErrorCode>;
		}

+22 −1

Original line number	Diff line number	Diff line
		@@ -9,7 +9,7 @@ use crate::{
		ids::{AttHandle, ConnectionId, TransactionId},
		GattCallbacks,
		},
		packets::{AttAttributeDataChild, AttErrorCode},
		packets::{AttAttributeDataChild, AttAttributeDataView, AttErrorCode},
		};

		use super::GattDatastore;
		@@ -138,4 +138,25 @@ impl GattDatastore for CallbackTransactionManager {
		Err(AttErrorCode::UNLIKELY_ERROR)
		}
		}

		async fn write_characteristic(
		&self,
		conn_id: ConnectionId,
		handle: AttHandle,
		data: AttAttributeDataView<'_>,
		) -> Result<(), AttErrorCode> {
		let (trans_id, rx) =
		self.pending_transactions.borrow_mut().start_new_transaction(conn_id)?;

		self.callbacks
		.on_server_write_characteristic(conn_id, trans_id, handle, 0, true, false, data);

		if let Ok(value) = rx.await {
		value.map(\|_\| ()) // the data passed back is irrelevant for write
		// requests
		} else {
		warn!("sender side of {trans_id:?} dropped while handling request - most likely this response will not be sent over the air");
		Err(AttErrorCode::UNLIKELY_ERROR)
		}
		}
		}

+39 −1

Original line number	Diff line number	Diff line
		@@ -11,7 +11,10 @@ use log::{error, info, warn};

		use crate::{
		do_in_rust_thread,
		packets::{AttAttributeDataChild, AttBuilder, AttErrorCode, Serializable, SerializeError},
		packets::{
		AttAttributeDataChild, AttAttributeDataView, AttBuilder, AttErrorCode, Serializable,
		SerializeError,
		},
		};

		use super::{
		@@ -54,6 +57,20 @@ mod inner {
		offset: u32,
		is_long: bool,
		);

		/// This callback is invoked when writing a characteristic - the client
		/// must reply using SendResponse
		#[cxx_name = "OnServerWriteCharacteristic"]
		fn on_server_write_characteristic(
		self: &GattServerCallbacks,
		conn_id: u16,
		trans_id: u32,
		attr_handle: u16,
		offset: u32,
		need_response: bool,
		is_prepare: bool,
		value: &[u8],
		);
		}

		/// What action the arbiter should take in response to an incoming packet
		@@ -143,6 +160,27 @@ impl GattCallbacks for GattCallbacksImpl {
		.unwrap()
		.on_server_read_characteristic(conn_id.0, trans_id.0, handle.0, offset, is_long);
		}

		fn on_server_write_characteristic(
		&self,
		conn_id: ConnectionId,
		trans_id: TransactionId,
		handle: AttHandle,
		offset: u32,
		need_response: bool,
		is_prepare: bool,
		value: AttAttributeDataView,
		) {
		self.0.as_ref().unwrap().on_server_write_characteristic(
		conn_id.0,
		trans_id.0,
		handle.0,
		offset,
		need_response,
		is_prepare,
		&value.get_raw_payload().collect::<Vec<_>>(),
		);
		}
		}

		/// Implementation of AttTransport wrapping the corresponding C++ method

+22 −0

Original line number	Diff line number	Diff line
		@@ -69,5 +69,27 @@ void GattServerCallbacks::OnServerReadCharacteristic(uint16_t conn_id,
		addr.value(), attr_handle, offset, is_long));
		}

		void GattServerCallbacks::OnServerWriteCharacteristic(
		uint16_t conn_id, uint32_t trans_id, uint16_t attr_handle, uint32_t offset,
		bool need_response, bool is_prepare,
		::rust::Slice<const uint8_t> value) const {
		auto addr = AddressOfConnection(conn_id);
		if (!addr.has_value()) {
		LOG_WARN(
		"Dropping server write characteristic since connection %d not found",
		conn_id);
		return;
		}

		auto buf = new uint8_t[value.size()];
		std::copy(value.begin(), value.end(), buf);

		do_in_jni_thread(
		FROM_HERE,
		base::Bind(callbacks.request_write_characteristic_cb, conn_id, trans_id,
		addr.value(), attr_handle, offset, need_response, is_prepare,
		base::Owned(buf), value.size()));
		}

		} // namespace gatt
		} // namespace bluetooth

+5 −0

Original line number	Diff line number	Diff line
		@@ -34,6 +34,11 @@ class GattServerCallbacks {
		uint16_t attr_handle, uint32_t offset,
		bool is_long) const;

		void OnServerWriteCharacteristic(uint16_t conn_id, uint32_t trans_id,
		uint16_t attr_handle, uint32_t offset,
		bool need_response, bool is_prepare,
		::rust::Slice<const uint8_t> value) const;

		private:
		const btgatt_server_callbacks_t& callbacks;
		};