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 "jni.h"
18 #include "jvmti.h"
19 
20 #include <vector>
21 
22 #include "jvmti_helper.h"
23 #include "jni_helper.h"
24 #include "test_env.h"
25 #include "scoped_local_ref.h"
26 
27 namespace art {
28 namespace common_monitors {
29 
Java_art_Monitors_getCurrentContendedMonitor(JNIEnv * env,jclass,jthread thr)30 extern "C" JNIEXPORT jobject JNICALL Java_art_Monitors_getCurrentContendedMonitor(
31     JNIEnv* env, jclass, jthread thr) {
32   jobject out = nullptr;
33   JvmtiErrorToException(env, jvmti_env, jvmti_env->GetCurrentContendedMonitor(thr, &out));
34   return out;
35 }
36 
Java_art_Monitors_getObjectMonitorUsage(JNIEnv * env,jclass,jobject obj)37 extern "C" JNIEXPORT jobject JNICALL Java_art_Monitors_getObjectMonitorUsage(
38     JNIEnv* env, jclass, jobject obj) {
39   ScopedLocalRef<jclass> klass(env, env->FindClass("art/Monitors$MonitorUsage"));
40   if (env->ExceptionCheck()) {
41     return nullptr;
42   }
43   jmethodID constructor = env->GetMethodID(
44       klass.get(),
45       "<init>",
46       "(Ljava/lang/Object;Ljava/lang/Thread;I[Ljava/lang/Thread;[Ljava/lang/Thread;)V");
47   if (env->ExceptionCheck()) {
48     return nullptr;
49   }
50   jvmtiMonitorUsage usage;
51   if (JvmtiErrorToException(env, jvmti_env, jvmti_env->GetObjectMonitorUsage(obj, &usage))) {
52     return nullptr;
53   }
54   jobjectArray wait = CreateObjectArray(env, usage.waiter_count, "java/lang/Thread",
55                                         [&](jint i) { return usage.waiters[i]; });
56   if (env->ExceptionCheck()) {
57     jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(usage.waiters));
58     jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(usage.notify_waiters));
59     return nullptr;
60   }
61   jobjectArray notify_wait = CreateObjectArray(env, usage.notify_waiter_count, "java/lang/Thread",
62                                                [&](jint i) { return usage.notify_waiters[i]; });
63   if (env->ExceptionCheck()) {
64     jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(usage.waiters));
65     jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(usage.notify_waiters));
66     return nullptr;
67   }
68   return env->NewObject(klass.get(), constructor,
69                         obj, usage.owner, usage.entry_count, wait, notify_wait);
70 }
71 
72 struct MonitorsData {
73   jclass test_klass;
74   jmethodID monitor_enter;
75   jmethodID monitor_entered;
76   jmethodID monitor_wait;
77   jmethodID monitor_waited;
78   jclass monitor_klass;
79 };
80 
monitorEnterCB(jvmtiEnv * jvmti,JNIEnv * jnienv,jthread thr,jobject obj)81 static void monitorEnterCB(jvmtiEnv* jvmti,
82                            JNIEnv* jnienv,
83                            jthread thr,
84                            jobject obj) {
85   MonitorsData* data = nullptr;
86   if (JvmtiErrorToException(jnienv, jvmti,
87                             jvmti->GetEnvironmentLocalStorage(reinterpret_cast<void**>(&data)))) {
88     return;
89   }
90   if (!jnienv->IsInstanceOf(obj, data->monitor_klass)) {
91     return;
92   }
93   jnienv->CallStaticVoidMethod(data->test_klass, data->monitor_enter, thr, obj);
94 }
monitorEnteredCB(jvmtiEnv * jvmti,JNIEnv * jnienv,jthread thr,jobject obj)95 static void monitorEnteredCB(jvmtiEnv* jvmti,
96                              JNIEnv* jnienv,
97                              jthread thr,
98                              jobject obj) {
99   MonitorsData* data = nullptr;
100   if (JvmtiErrorToException(jnienv, jvmti,
101                             jvmti->GetEnvironmentLocalStorage(reinterpret_cast<void**>(&data)))) {
102     return;
103   }
104   if (!jnienv->IsInstanceOf(obj, data->monitor_klass)) {
105     return;
106   }
107   jnienv->CallStaticVoidMethod(data->test_klass, data->monitor_entered, thr, obj);
108 }
monitorWaitCB(jvmtiEnv * jvmti,JNIEnv * jnienv,jthread thr,jobject obj,jlong timeout)109 static void monitorWaitCB(jvmtiEnv* jvmti,
110                           JNIEnv* jnienv,
111                           jthread thr,
112                           jobject obj,
113                           jlong timeout) {
114   MonitorsData* data = nullptr;
115   if (JvmtiErrorToException(jnienv, jvmti,
116                             jvmti->GetEnvironmentLocalStorage(reinterpret_cast<void**>(&data)))) {
117     return;
118   }
119   if (!jnienv->IsInstanceOf(obj, data->monitor_klass)) {
120     return;
121   }
122   jnienv->CallStaticVoidMethod(data->test_klass, data->monitor_wait, thr, obj, timeout);
123 }
monitorWaitedCB(jvmtiEnv * jvmti,JNIEnv * jnienv,jthread thr,jobject obj,jboolean timed_out)124 static void monitorWaitedCB(jvmtiEnv* jvmti,
125                             JNIEnv* jnienv,
126                             jthread thr,
127                             jobject obj,
128                             jboolean timed_out) {
129   MonitorsData* data = nullptr;
130   if (JvmtiErrorToException(jnienv, jvmti,
131                             jvmti->GetEnvironmentLocalStorage(reinterpret_cast<void**>(&data)))) {
132     return;
133   }
134   if (!jnienv->IsInstanceOf(obj, data->monitor_klass)) {
135     return;
136   }
137   jnienv->CallStaticVoidMethod(data->test_klass, data->monitor_waited, thr, obj, timed_out);
138 }
139 
Java_art_Monitors_setupMonitorEvents(JNIEnv * env,jclass,jclass test_klass,jobject monitor_enter,jobject monitor_entered,jobject monitor_wait,jobject monitor_waited,jclass monitor_klass,jthread thr)140 extern "C" JNIEXPORT void JNICALL Java_art_Monitors_setupMonitorEvents(
141     JNIEnv* env,
142     jclass,
143     jclass test_klass,
144     jobject monitor_enter,
145     jobject monitor_entered,
146     jobject monitor_wait,
147     jobject monitor_waited,
148     jclass monitor_klass,
149     jthread thr) {
150   MonitorsData* data = nullptr;
151   if (JvmtiErrorToException(env,
152                             jvmti_env,
153                             jvmti_env->Allocate(sizeof(MonitorsData),
154                                                 reinterpret_cast<unsigned char**>(&data)))) {
155     return;
156   }
157   jvmtiCapabilities caps;
158   memset(&caps, 0, sizeof(caps));
159   caps.can_generate_monitor_events = 1;
160   if (JvmtiErrorToException(env, jvmti_env, jvmti_env->AddCapabilities(&caps))) {
161     return;
162   }
163 
164   memset(data, 0, sizeof(MonitorsData));
165   data->test_klass = reinterpret_cast<jclass>(env->NewGlobalRef(test_klass));
166   data->monitor_enter = env->FromReflectedMethod(monitor_enter);
167   data->monitor_entered = env->FromReflectedMethod(monitor_entered);
168   data->monitor_wait = env->FromReflectedMethod(monitor_wait);
169   data->monitor_waited = env->FromReflectedMethod(monitor_waited);
170   data->monitor_klass = reinterpret_cast<jclass>(env->NewGlobalRef(monitor_klass));
171   MonitorsData* old_data = nullptr;
172   if (JvmtiErrorToException(env, jvmti_env,
173                             jvmti_env->GetEnvironmentLocalStorage(
174                                 reinterpret_cast<void**>(&old_data)))) {
175     return;
176   } else if (old_data != nullptr && old_data->test_klass != nullptr) {
177     ScopedLocalRef<jclass> rt_exception(env, env->FindClass("java/lang/RuntimeException"));
178     env->ThrowNew(rt_exception.get(), "Environment already has local storage set!");
179     return;
180   }
181   if (JvmtiErrorToException(env, jvmti_env, jvmti_env->SetEnvironmentLocalStorage(data))) {
182     return;
183   }
184 
185   current_callbacks.MonitorContendedEnter = monitorEnterCB;
186   current_callbacks.MonitorContendedEntered = monitorEnteredCB;
187   current_callbacks.MonitorWait = monitorWaitCB;
188   current_callbacks.MonitorWaited = monitorWaitedCB;
189   if (JvmtiErrorToException(env,
190                             jvmti_env,
191                             jvmti_env->SetEventCallbacks(&current_callbacks,
192                                                          sizeof(current_callbacks)))) {
193     return;
194   }
195   if (JvmtiErrorToException(env,
196                             jvmti_env,
197                             jvmti_env->SetEventNotificationMode(
198                                 JVMTI_ENABLE, JVMTI_EVENT_MONITOR_CONTENDED_ENTER, thr))) {
199     return;
200   }
201   if (JvmtiErrorToException(env,
202                             jvmti_env,
203                             jvmti_env->SetEventNotificationMode(
204                                 JVMTI_ENABLE, JVMTI_EVENT_MONITOR_CONTENDED_ENTERED, thr))) {
205     return;
206   }
207   if (JvmtiErrorToException(env,
208                             jvmti_env,
209                             jvmti_env->SetEventNotificationMode(
210                                 JVMTI_ENABLE, JVMTI_EVENT_MONITOR_WAIT, thr))) {
211     return;
212   }
213   if (JvmtiErrorToException(env,
214                             jvmti_env,
215                             jvmti_env->SetEventNotificationMode(
216                                 JVMTI_ENABLE, JVMTI_EVENT_MONITOR_WAITED, thr))) {
217     return;
218   }
219 }
220 
221 }  // namespace common_monitors
222 }  // namespace art
223 
224