commit 35d77caf8e7e34fa6ac8f4bbc75a52631adc0272
author Christopher Wiley <wiley@google.com> Tue Mar 08 10:49:51 2016 -0800
committer Christopher Wiley <wiley@google.com> Tue Mar 08 15:29:13 2016 -0800
tree 3bc3673b9a82cf7c01e5d928495aff51d0e4c53c
parent e6b6843c5fc19976677706518c4875a78cc736bb

libbinder: Make null handling explicit for strong binders

Bug: 27156495
Test: Compiles

Change-Id: I62cade1761377a9ec2921a758307582552e4c2ac

include/binder/Parcel.h

diff --git a/include/binder/Parcel.h b/include/binder/Parcel.h
index 44fd59e..9c3877e 100644
--- a/include/binder/Parcel.h
+++ b/include/binder/Parcel.h
@@ -252,6 +252,7 @@
     const char16_t*     readString16Inplace(size_t* outLen) const;
     sp<IBinder>         readStrongBinder() const;
     status_t            readStrongBinder(sp<IBinder>* val) const;
+    status_t            readNullableStrongBinder(sp<IBinder>* val) const;
     wp<IBinder>         readWeakBinder() const;
 
     template<typename T>
@@ -268,6 +269,9 @@
     template<typename T>
     status_t            readStrongBinder(sp<T>* val) const;
 
+    template<typename T>
+    status_t            readNullableStrongBinder(sp<T>* val) const;
+
     status_t            readStrongBinderVector(std::unique_ptr<std::vector<sp<IBinder>>>* val) const;
     status_t            readStrongBinderVector(std::vector<sp<IBinder>>* val) const;
 
@@ -574,6 +578,20 @@
     return ret;
 }
 
+template<typename T>
+status_t Parcel::readNullableStrongBinder(sp<T>* val) const {
+    sp<IBinder> tmp;
+    status_t ret = readNullableStrongBinder(&tmp);
+
+    if (ret == OK) {
+        *val = interface_cast<T>(tmp);
+
+        if (val->get() == nullptr) {
+            return UNKNOWN_ERROR;
+        }
+    }
+}
+
 template<typename T, typename U>
 status_t Parcel::unsafeReadTypedVector(
         std::vector<T>* val,