libbinder_ndk_unit_test: avoid race

Avoid race where the test starts before the service
it is testing is started.

Bug: 290569617
Test: libbinder_ndk_unit_test
Change-Id: I487f1ce59c6d21c87c7b54bfd721da9883f0501b

1 files changed, 9 insertions, 3 deletions

diff --git a/libs/binder/ndk/tests/libbinder_ndk_unit_test.cpp b/libs/binder/ndk/tests/libbinder_ndk_unit_test.cpp
index 27ce615565..089e55ffb1 100644
--- a/libs/binder/ndk/tests/libbinder_ndk_unit_test.cpp
+++ b/libs/binder/ndk/tests/libbinder_ndk_unit_test.cpp
@@ -377,18 +377,24 @@ TEST(NdkBinder, CantHaveTwoLocalBinderClassesWithSameDescriptor) {
 }
 
 TEST(NdkBinder, GetTestServiceStressTest) {
-    // libbinder has some complicated logic to make sure only one instance of
-    // ABpBinder is associated with each binder.
-
     constexpr size_t kNumThreads = 10;
     constexpr size_t kNumCalls = 1000;
     std::vector<std::thread> threads;
 
+    // this is not a lazy service, but we must make sure that it's started before calling
+    // checkService on it, since the other process serving it might not be started yet.
+    {
+        // getService, not waitForService, to take advantage of timeout
+        auto binder = ndk::SpAIBinder(AServiceManager_getService(IFoo::kSomeInstanceName));
+        ASSERT_NE(nullptr, binder.get());
+    }
+
     for (size_t i = 0; i < kNumThreads; i++) {
         threads.push_back(std::thread([&]() {
             for (size_t j = 0; j < kNumCalls; j++) {
                 auto binder =
                         ndk::SpAIBinder(AServiceManager_checkService(IFoo::kSomeInstanceName));
+                ASSERT_NE(nullptr, binder.get());
                 EXPECT_EQ(STATUS_OK, AIBinder_ping(binder.get()));
             }
         }));