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/*
* Copyright (C) 2019 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.
*/
#include <stdio.h>
#include <vector>
#include "android-base/logging.h"
#include "android-base/macros.h"
#include "jni.h"
#include "jvmti.h"
// Test infrastructure
#include "jvmti_helper.h"
#include "scoped_local_ref.h"
#include "test_env.h"
namespace art {
namespace Test2005PauseAllRedefineMultithreaded {
static constexpr jlong kRedefinedObjectTag = 0xDEADBEEF;
extern "C" JNIEXPORT void JNICALL
Java_art_Test2005_UpdateFieldValuesAndResumeThreads(JNIEnv* env,
[[maybe_unused]] jclass klass,
jobjectArray threads_arr,
jclass redefined_class,
jobjectArray new_fields,
jstring default_val) {
std::vector<jthread> threads;
threads.reserve(env->GetArrayLength(threads_arr));
for (jint i = 0; i < env->GetArrayLength(threads_arr); i++) {
threads.push_back(env->GetObjectArrayElement(threads_arr, i));
}
std::vector<jfieldID> fields;
fields.reserve(env->GetArrayLength(new_fields));
for (jint i = 0; i < env->GetArrayLength(new_fields); i++) {
fields.push_back(env->FromReflectedField(env->GetObjectArrayElement(new_fields, i)));
}
// Tag every instance of the redefined class with kRedefinedObjectTag
CHECK_EQ(jvmti_env->IterateOverInstancesOfClass(
redefined_class,
JVMTI_HEAP_OBJECT_EITHER,
[]([[maybe_unused]] jlong class_tag,
[[maybe_unused]] jlong size,
jlong* tag_ptr,
[[maybe_unused]] void* user_data) -> jvmtiIterationControl {
*tag_ptr = kRedefinedObjectTag;
return JVMTI_ITERATION_CONTINUE;
},
nullptr),
JVMTI_ERROR_NONE);
jobject* objs;
jint cnt;
// Get the objects.
CHECK_EQ(jvmti_env->GetObjectsWithTags(1, &kRedefinedObjectTag, &cnt, &objs, nullptr),
JVMTI_ERROR_NONE);
// Set every field that's null
for (jint i = 0; i < cnt; i++) {
jobject obj = objs[i];
for (jfieldID field : fields) {
if (ScopedLocalRef<jobject>(env, env->GetObjectField(obj, field)).get() == nullptr) {
env->SetObjectField(obj, field, default_val);
}
}
}
LOG(INFO) << "Setting " << cnt << " objects with default values";
if (!threads.empty()) {
std::vector<jvmtiError> errs(threads.size(), JVMTI_ERROR_NONE);
CHECK_EQ(jvmti_env->ResumeThreadList(threads.size(), threads.data(), errs.data()),
JVMTI_ERROR_NONE);
}
jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(objs));
}
extern "C" JNIEXPORT jobject JNICALL
Java_Main_fastNativeSleepAndReturnInteger42(JNIEnv* env, [[maybe_unused]] jclass klass) {
jclass integer_class = env->FindClass("java/lang/Integer");
CHECK(integer_class != nullptr);
jmethodID integer_value_of =
env->GetStaticMethodID(integer_class, "valueOf", "(I)Ljava/lang/Integer;");
CHECK(integer_value_of != nullptr);
jobject value = env->CallStaticObjectMethod(integer_class, integer_value_of, 42);
CHECK(value != nullptr);
// Sleep for 500ms, blocking thread suspension (this method is @FastNative).
// Except for some odd thread timing, this should ensure that the suspend
// request from the redefinition thread is seen by the suspend check in the
// JNI stub when we exit this function and then processed with the JNI stub
// still on the stack. The instrumentation previously erroneously
// intercepted returning to the JNI stub and the "instrumentation exit"
// handler treated the return value `jobject` as `mirror::Object*`.
usleep(500000);
return value;
}
} // namespace Test2005PauseAllRedefineMultithreaded
} // namespace art
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