Fix race conditions for lazy services.

Add hidlFqName/hidlName to registerClientCallbacks to make it more
explicit, provide better errors, and for general sanity.

Add tryUnregister so that a service can unregister itself before
shutting down.

Bug: 123318663
Test: hidl_test, manual

Change-Id: I3ee26ba96dbc9732e72aaa16281abc47ce6a02c9

1 files changed, 4 insertions, 0 deletions

diff --git a/transport/HidlTransportUtils.cpp b/transport/HidlTransportUtils.cpp
index 4e952eb..8c61281 100644
--- a/transport/HidlTransportUtils.cpp
+++ b/transport/HidlTransportUtils.cpp
@@ -56,6 +56,10 @@ Return<bool> canCastInterface(IBase* interface, const char* castTo, bool emitErr
 }
 
 std::string getDescriptor(IBase* interface) {
+    if (interface == nullptr) {
+        return "";
+    }
+
     std::string myDescriptor{};
     auto ret = interface->interfaceDescriptor([&](const hidl_string &types) {
         myDescriptor = types.c_str();