libbinderthreadstateutils: don't init binder

Don't initialize binder/hwbinder thread state if they
aren't already initialized. This is fine - if we
know they aren't initialized, then there is no binder
call going.

Bug: 205282403
Test: libbinderthreadstateutils_test
TesT: binderRpcTest (because it uses these APIs in a special way)
Change-Id: Id67010bb15559e85dd764746525562acc7e1f13c

1 files changed, 19 insertions, 0 deletions

diff --git a/libs/binderthreadstate/test.cpp b/libs/binderthreadstate/test.cpp
index df1f35d9a7..b5c4010c7a 100644
--- a/libs/binderthreadstate/test.cpp
+++ b/libs/binderthreadstate/test.cpp
@@ -16,11 +16,16 @@
 
 #include <BnAidlStuff.h>
 #include <android-base/logging.h>
+#include <binder/IPCThreadState.h>
 #include <binder/IServiceManager.h>
 #include <binderthreadstate/CallerUtils.h>
 #include <binderthreadstateutilstest/1.0/IHidlStuff.h>
 #include <gtest/gtest.h>
 #include <hidl/HidlTransportSupport.h>
+#include <hwbinder/IPCThreadState.h>
+
+#include <thread>
+
 #include <linux/prctl.h>
 #include <sys/prctl.h>
 
@@ -154,6 +159,20 @@ TEST(BinderThreadState, LocalAidlCall) {
     EXPECT_TRUE(server->callLocal().isOk());
 }
 
+TEST(BinderThreadState, DoesntInitializeBinderDriver) {
+    // this is on another thread, because it's testing thread-specific
+    // state and we expect it not to be initialized.
+    std::thread([&] {
+        EXPECT_EQ(nullptr, android::IPCThreadState::selfOrNull());
+        EXPECT_EQ(nullptr, android::hardware::IPCThreadState::selfOrNull());
+
+        (void)getCurrentServingCall();
+
+        EXPECT_EQ(nullptr, android::IPCThreadState::selfOrNull());
+        EXPECT_EQ(nullptr, android::hardware::IPCThreadState::selfOrNull());
+    }).join();
+}
+
 TEST(BindThreadState, RemoteHidlCall) {
     auto stuff = IHidlStuff::getService(id2name(kP1Id));
     ASSERT_NE(nullptr, stuff);