1 /*
2  * Copyright (C) 2017 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 <mutex>
18 
19 #include "jni.h"
20 #include "jvmti.h"
21 
22 #include "android-base/logging.h"
23 #include "android-base/stringprintf.h"
24 #include "jvmti_helper.h"
25 #include "scoped_local_ref.h"
26 #include "scoped_utf_chars.h"
27 #include "test_env.h"
28 
29 namespace art {
30 
GetClassName(JNIEnv * jni_env,jclass cls)31 static std::string GetClassName(JNIEnv* jni_env, jclass cls) {
32   ScopedLocalRef<jclass> class_class(jni_env, jni_env->GetObjectClass(cls));
33   jmethodID mid = jni_env->GetMethodID(class_class.get(), "getName", "()Ljava/lang/String;");
34   ScopedLocalRef<jstring> str(
35       jni_env, reinterpret_cast<jstring>(jni_env->CallObjectMethod(cls, mid)));
36   ScopedUtfChars utf_chars(jni_env, str.get());
37   return utf_chars.c_str();
38 }
39 
40 static std::mutex gLock;
41 static std::string gCollection;
42 
ObjectAllocated(jvmtiEnv * ti_env ATTRIBUTE_UNUSED,JNIEnv * jni_env,jthread thread ATTRIBUTE_UNUSED,jobject object,jclass object_klass,jlong size)43 static void JNICALL ObjectAllocated(jvmtiEnv* ti_env ATTRIBUTE_UNUSED,
44                                     JNIEnv* jni_env,
45                                     jthread thread ATTRIBUTE_UNUSED,
46                                     jobject object,
47                                     jclass object_klass,
48                                     jlong size) {
49   std::string object_klass_descriptor = GetClassName(jni_env, object_klass);
50   ScopedLocalRef<jclass> object_klass2(jni_env, jni_env->GetObjectClass(object));
51   std::string object_klass_descriptor2 = GetClassName(jni_env, object_klass2.get());
52   std::string result = android::base::StringPrintf("ObjectAllocated type %s/%s size %zu",
53                                                    object_klass_descriptor.c_str(),
54                                                    object_klass_descriptor2.c_str(),
55                                                    static_cast<size_t>(size));
56   std::unique_lock<std::mutex> mu(gLock);
57   gCollection += result + "#";
58 }
59 
Java_android_jvmti_cts_JvmtiTrackingTest_setupObjectAllocCallback(JNIEnv * env,jclass klass ATTRIBUTE_UNUSED,jboolean enable)60 extern "C" JNIEXPORT void JNICALL Java_android_jvmti_cts_JvmtiTrackingTest_setupObjectAllocCallback(
61     JNIEnv* env, jclass klass ATTRIBUTE_UNUSED, jboolean enable) {
62   jvmtiEventCallbacks callbacks;
63   memset(&callbacks, 0, sizeof(jvmtiEventCallbacks));
64   callbacks.VMObjectAlloc = enable ? ObjectAllocated : nullptr;
65 
66   jvmtiError ret = jvmti_env->SetEventCallbacks(&callbacks, sizeof(callbacks));
67   JvmtiErrorToException(env, jvmti_env, ret);
68 }
69 
Java_android_jvmti_cts_JvmtiTrackingTest_enableAllocationTracking(JNIEnv * env,jclass klass ATTRIBUTE_UNUSED,jthread thread,jboolean enable)70 extern "C" JNIEXPORT void JNICALL Java_android_jvmti_cts_JvmtiTrackingTest_enableAllocationTracking(
71     JNIEnv* env, jclass klass ATTRIBUTE_UNUSED, jthread thread, jboolean enable) {
72   jvmtiError ret = jvmti_env->SetEventNotificationMode(
73       enable ? JVMTI_ENABLE : JVMTI_DISABLE,
74       JVMTI_EVENT_VM_OBJECT_ALLOC,
75       thread);
76   JvmtiErrorToException(env, jvmti_env, ret);
77 }
78 
79 extern "C" JNIEXPORT
Java_android_jvmti_cts_JvmtiTrackingTest_getAndResetAllocationTrackingString(JNIEnv * env,jclass klass ATTRIBUTE_UNUSED)80 jstring JNICALL Java_android_jvmti_cts_JvmtiTrackingTest_getAndResetAllocationTrackingString(
81     JNIEnv* env, jclass klass ATTRIBUTE_UNUSED) {
82   // We will have a string allocation. So only do the C++ string retrieval under lock.
83   std::string result;
84   {
85     std::unique_lock<std::mutex> mu(gLock);
86     result.swap(gCollection);
87   }
88 
89   if (result.empty()) {
90     return nullptr;
91   }
92 
93   return env->NewStringUTF(result.c_str());
94 }
95 
96 }  // namespace art
97