Add HIDL token passing mechanism.

Test: Mirroring, Camera, Photos, YouTube and Play Movies apps.
Bug: 35442034
Change-Id: I7216f853ad42f115fd00ed9031793d8d1e7d1a03
diff --git a/libs/binder/HalToken.cpp b/libs/binder/HalToken.cpp
new file mode 100644
index 0000000..6e71a52
--- /dev/null
+++ b/libs/binder/HalToken.cpp
@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2005 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "HalToken"
+
+#include <utils/Log.h>
+#include <binder/HalToken.h>
+
+#include <android/hidl/token/1.0/ITokenManager.h>
+
+namespace android {
+
+using ::android::hidl::token::V1_0::ITokenManager;
+
+sp<ITokenManager> gTokenManager = nullptr;
+
+ITokenManager* getTokenManager() {
+    if (gTokenManager != nullptr) {
+        return gTokenManager.get();
+    }
+    gTokenManager = ITokenManager::getService();
+    if (gTokenManager == nullptr) {
+        ALOGE("Cannot retrieve TokenManager.");
+    }
+    return gTokenManager.get();
+}
+
+sp<HInterface> retrieveHalInterface(const HalToken& token) {
+    auto transaction = getTokenManager()->get(token);
+    if (!transaction.isOk()) {
+        ALOGE("getHalInterface: Cannot obtain interface from token.");
+        return nullptr;
+    }
+    return static_cast<sp<HInterface> >(transaction);
+}
+
+bool createHalToken(const sp<HInterface>& interface, HalToken* token) {
+    auto transaction = getTokenManager()->createToken(interface);
+    if (!transaction.isOk()) {
+        ALOGE("createHalToken: Cannot create token from interface.");
+        return false;
+    }
+    *token = static_cast<HalToken>(transaction);
+    return true;
+}
+
+bool deleteHalToken(const HalToken& token) {
+    auto transaction = getTokenManager()->unregister(token);
+    if (!transaction.isOk()) {
+        ALOGE("deleteHalToken: Cannot unregister hal token.");
+        return false;
+    }
+    return true;
+}
+
+}; // namespace android
+