libbinder_ndk: clarify AParcel_writeStatusHeader
This function only writes a status header if it is useful, but it
returns an error in this case. This is now documented here.
Bug: 111445392
Test: N/A
Change-Id: I43082ad62ccc309efe69ae486e2ce7267f1af638
diff --git a/libs/binder/ndk/include_ndk/android/binder_parcel.h b/libs/binder/ndk/include_ndk/android/binder_parcel.h
index 271810a..c35aee7 100644
--- a/libs/binder/ndk/include_ndk/android/binder_parcel.h
+++ b/libs/binder/ndk/include_ndk/android/binder_parcel.h
@@ -68,6 +68,12 @@
/**
* Writes an AStatus object to the next location in a non-null parcel.
+ *
+ * If the status is considered to be a low-level status and has no additional information other
+ * than a binder_status_t (for instance, if it is created with AStatus_fromStatus), then that
+ * status will be returned from this method and nothing will be written to the parcel. If either
+ * this happens or if writing the status object itself fails, the return value from this function
+ * should be propagated to the client, and AParcel_readStatusHeader shouldn't be called.
*/
binder_status_t AParcel_writeStatusHeader(AParcel* parcel, const AStatus* status);