1 /*
2  * Copyright (C) 2020 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #define LOG_TAG "ServiceManager"
18 //#define LOG_NDEBUG 0
19 #include <android-base/logging.h>
20 
21 #include <binder/IInterface.h>
22 #include <binder/IServiceManager.h>
23 #include <nativehelper/JNIHelp.h>
24 
25 #include "android_util_Binder.h"
26 #include "core_jni_helpers.h"
27 
28 namespace android {
29 
30 // Native because we have a client-side wait in waitForService() and we do not
31 // want an unnecessary second copy of it.
32 static jobject android_os_ServiceManager_waitForService(
33         JNIEnv *env,
34         jclass /* clazzObj */,
35         jstring serviceNameObj) {
36 
37     const jchar* serviceName = env->GetStringCritical(serviceNameObj, nullptr);
38     if (!serviceName) {
39         jniThrowNullPointerException(env, nullptr);
40         return nullptr;
41     }
42     String16 nameCopy = String16(reinterpret_cast<const char16_t *>(serviceName),
43             env->GetStringLength(serviceNameObj));
44     env->ReleaseStringCritical(serviceNameObj, serviceName);
45 
46     sp<IBinder> service = defaultServiceManager()->waitForService(nameCopy);
47 
48     if (!service) {
49         return nullptr;
50     }
51 
52     return javaObjectForIBinder(env, service);
53 }
54 
55 // ----------------------------------------------------------------------------
56 
57 static const JNINativeMethod method_table[] = {
58      /* name, signature, funcPtr */
59     {
60         "waitForService",
61         "(Ljava/lang/String;)Landroid/os/IBinder;",
62         (void*)android_os_ServiceManager_waitForService
63     },
64 };
65 
66 int register_android_os_ServiceManager(JNIEnv* env) {
67     return RegisterMethodsOrDie(
68             env, "android/os/ServiceManager", method_table, NELEM(method_table));
69 }
70 
71 }; // namespace android
72