Add test to open and close with no mmap

Add a test to check that alloc->buffers
is properly initialized when calling
close after open with no mmap.

Bug: 36007193
Test: run binderDriverInterfaceTest
Change-Id: I94af8499e65714b1b09ac063459eacf05504262a
Signed-off-by: Sherry Yang <sherryy@android.com>
diff --git a/libs/binder/tests/binderDriverInterfaceTest.cpp b/libs/binder/tests/binderDriverInterfaceTest.cpp
index ff5912f..b14631d 100644
--- a/libs/binder/tests/binderDriverInterfaceTest.cpp
+++ b/libs/binder/tests/binderDriverInterfaceTest.cpp
@@ -139,6 +139,12 @@
     ASSERT_EQ(BINDER_CURRENT_PROTOCOL_VERSION, version.protocol_version);
 }
 
+TEST_F(BinderDriverInterfaceTest, OpenNoMmap) {
+    int binderFd = open(BINDER_DEV_NAME, O_RDWR | O_NONBLOCK | O_CLOEXEC);
+    ASSERT_GE(binderFd, 0);
+    close(binderFd);
+}
+
 TEST_F(BinderDriverInterfaceTest, WriteReadNull) {
     binderTestIoctlErr1(BINDER_WRITE_READ, NULL, EFAULT);
 }