Add canonical types adapters for NNAPI AIDL interface
Also:
* Add missing AIDL<->CT conversions
* Add AIDL-specific info to neuralnetworks/utils/README.md
* Add mock classes and tests AIDL adapters
Bug: 179015258
Test: neuralnetworks_utils_hal_test
Change-Id: Ifa98fadd46dca5dbf9b3ceb4da811aa8da45b6e4
Merged-In: Ifa98fadd46dca5dbf9b3ceb4da811aa8da45b6e4
(cherry picked from commit 3b93b0b56a4f5128eaa942d804dd490317c0abcb)
diff --git a/neuralnetworks/utils/README.md b/neuralnetworks/utils/README.md
index 45ca0b4..87b3f9f 100644
--- a/neuralnetworks/utils/README.md
+++ b/neuralnetworks/utils/README.md
@@ -49,7 +49,9 @@
(i.e., not as a nested class) or used in a subsequent version of the NN HAL. Prefer using `convert`
over `unvalidatedConvert`.
-# HIDL Interface Lifetimes across Processes
+# Interface Lifetimes across Processes
+
+## HIDL
Some notes about HIDL interface objects and lifetimes across processes:
@@ -68,7 +70,20 @@
If the process which created the HIDL interface object dies, any call on this object from another
process will result in a HIDL transport error with the code `DEAD_OBJECT`.
-# Protecting Asynchronous Calls across HIDL
+## AIDL
+
+We use NDK backend for AIDL interfaces. Handling of lifetimes is generally the same with the
+following differences:
+* Interfaces inherit from `ndk::ICInterface`, which inherits from `ndk::SharedRefBase`. The latter
+ is an analog of `::android::RefBase` using `std::shared_ptr` for reference counting.
+* AIDL calls return `ndk::ScopedAStatus` which wraps fields of types `binder_status_t` and
+ `binder_exception_t`. In case the call is made on a dead object, the call will return
+ `ndk::ScopedAStatus` with exception `EX_TRANSACTION_FAILED` and binder status
+ `STATUS_DEAD_OBJECT`.
+
+# Protecting Asynchronous Calls
+
+## Across HIDL
Some notes about asynchronous calls across HIDL:
@@ -95,3 +110,17 @@
driver process has died, and `DeathHandler` will unblock any thread waiting on the results of an
`IProtectedCallback` callback object that may otherwise not be signaled. In order for this to work,
the `IProtectedCallback` object must have been registered via `DeathHandler::protectCallback()`.
+
+## Across AIDL
+
+We use NDK backend for AIDL interfaces. Handling of asynchronous calls is generally the same with
+the following differences:
+* AIDL calls return `ndk::ScopedAStatus` which wraps fields of types `binder_status_t` and
+ `binder_exception_t`. In case the call is made on a dead object, the call will return
+ `ndk::ScopedAStatus` with exception `EX_TRANSACTION_FAILED` and binder status
+ `STATUS_DEAD_OBJECT`.
+* AIDL interface doesn't contain asynchronous `IPreparedModel::execute`.
+* Service death is handled using `AIBinder_DeathRecipient` object which is linked to an interface
+ object using `AIBinder_linkToDeath`. nnapi/hal/aidl/ProtectCallback.h provides `DeathHandler`
+ object that is a direct analog of HIDL `DeathHandler`, only using libbinder_ndk objects for
+ implementation.
diff --git a/neuralnetworks/utils/common/Android.bp b/neuralnetworks/utils/common/Android.bp
index 6162fe8..2ed1e40 100644
--- a/neuralnetworks/utils/common/Android.bp
+++ b/neuralnetworks/utils/common/Android.bp
@@ -35,8 +35,10 @@
"neuralnetworks_types",
],
shared_libs: [
+ "android.hardware.neuralnetworks-V1-ndk_platform",
"libhidlbase",
"libnativewindow",
+ "libbinder_ndk",
],
}
diff --git a/neuralnetworks/utils/common/include/nnapi/hal/CommonUtils.h b/neuralnetworks/utils/common/include/nnapi/hal/CommonUtils.h
index 2f6112a..8fe6b90 100644
--- a/neuralnetworks/utils/common/include/nnapi/hal/CommonUtils.h
+++ b/neuralnetworks/utils/common/include/nnapi/hal/CommonUtils.h
@@ -32,6 +32,8 @@
// Shorthands
namespace aidl::android::hardware::neuralnetworks {
namespace aidl_hal = ::aidl::android::hardware::neuralnetworks;
+namespace hal = ::android::hardware::neuralnetworks;
+namespace nn = ::android::nn;
} // namespace aidl::android::hardware::neuralnetworks
// Shorthands