1 /* 2 * Copyright (C) 2016 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 #include <dlfcn.h> 18 #include <iostream> 19 20 #include "base/casts.h" 21 #include "base/macros.h" 22 #include "java_vm_ext.h" 23 #include "jni_env_ext.h" 24 #include "thread-current-inl.h" 25 26 namespace art { 27 namespace { 28 29 static volatile std::atomic<bool> vm_was_shutdown(false); 30 static const int kThreadCount = 4; 31 32 static std::atomic<int> barrier_count(kThreadCount + 1); 33 34 static void JniThreadBarrierWait() { 35 barrier_count--; 36 while (barrier_count.load() != 0) { 37 usleep(1000); 38 } 39 } 40 41 extern "C" JNIEXPORT void JNICALL Java_Main_waitAndCallIntoJniEnv(JNIEnv* env, jclass) { 42 // Wait for all threads to enter JNI together. 43 JniThreadBarrierWait(); 44 // Wait until the runtime is shutdown. 45 while (!vm_was_shutdown.load()) { 46 usleep(1000); 47 } 48 std::cout << "About to call exception check\n"; 49 env->ExceptionCheck(); 50 LOG(ERROR) << "Should not be reached!"; 51 } 52 53 // NO_RETURN does not work with extern "C" for target builds. 54 extern "C" JNIEXPORT void JNICALL Java_Main_destroyJavaVMAndExit(JNIEnv* env, jclass) { 55 // Wait for all threads to enter JNI together. 56 JniThreadBarrierWait(); 57 // Fake up the managed stack so we can detach. 58 Thread* const self = Thread::Current(); 59 self->SetTopOfStack(nullptr); 60 self->SetTopOfShadowStack(nullptr); 61 JavaVM* vm = down_cast<JNIEnvExt*>(env)->vm; 62 vm->DetachCurrentThread(); 63 // Open ourself again to make sure the native library does not get unloaded from 64 // underneath us due to DestroyJavaVM. b/28406866 65 void* handle = dlopen(kIsDebugBuild ? "libarttestd.so" : "libarttest.so", RTLD_NOW); 66 CHECK(handle != nullptr); 67 vm->DestroyJavaVM(); 68 vm_was_shutdown.store(true); 69 // Give threads some time to get stuck in ExceptionCheck. 70 usleep(1000000); 71 if (env != nullptr) { 72 // Use env != nullptr to trick noreturn. 73 exit(0); 74 } 75 } 76 77 } // namespace 78 } // namespace art 79
