1 /*
   2  * Copyright (c) 2007, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <jni.h>
  27 #include <jvmti.h>
  28 #include <aod.h>
  29 #include <jvmti_aod.h>
  30 
  31 extern "C" {
  32 
  33 /*
  34  * Expected agent work scenario:
  35  * - from Agent_OnAttach function start auxiliary thread waiting on 'gcFinishMonitor'
  36  * - receive GarbageCollectionStart event
  37  * - receive GarbageCollectionFinish event, notify 'gcFinishMonitor'
  38  * - notified auxiliary thread calls function 'nsk_aod_agentFinished' and agent completes work
  39  * (such schema is used because of agent can't call nsk_aod_agentFinished from GarbageCollectionFinish handler,
  40  * nsk_aod_agentFinished calls JNI functions and it is prohibited in GarbageCollectionFinish handler)
  41  *
  42  */
  43 
  44 static Options* options = NULL;
  45 static const char* agentName;
  46 
  47 static jvmtiEvent testEvents[] = {JVMTI_EVENT_GARBAGE_COLLECTION_START, JVMTI_EVENT_GARBAGE_COLLECTION_FINISH};
  48 static const int testEventsNumber = 2;
  49 
  50 static jrawMonitorID gcFinishMonitor;
  51 
  52 static volatile int gcStartEventReceived = 0;
  53 
  54 static volatile int gcFinishEventReceived = 0;
  55 
  56 static volatile int success = 1;
  57 
  58 void JNICALL garbageCollectionStartHandler(jvmtiEnv *jvmti) {
  59     NSK_DISPLAY1("%s: GC start event received\n", agentName);
  60 
  61     gcStartEventReceived = 1;
  62 }
  63 
  64 void JNICALL garbageCollectionFinishHandler(jvmtiEnv *jvmti) {
  65     int auxiliaryThreadNotified = 0;
  66 
  67     NSK_DISPLAY1("%s: GC finish event received\n", agentName);
  68 
  69     if (!gcStartEventReceived) {
  70         NSK_COMPLAIN1("%s: GC start event wasn't received before GC finish event\n", agentName);
  71         success = 0;
  72     }
  73 
  74     if (NSK_JVMTI_VERIFY(jvmti->RawMonitorEnter(gcFinishMonitor))) {
  75 
  76         gcFinishEventReceived = 1;
  77 
  78         if (NSK_JVMTI_VERIFY(jvmti->RawMonitorNotify(gcFinishMonitor))) {
  79             auxiliaryThreadNotified = 1;
  80         }
  81 
  82         if (!NSK_JVMTI_VERIFY(jvmti->RawMonitorExit(gcFinishMonitor))) {
  83             success = 0;
  84         }
  85     } else {
  86         success = 0;
  87     }
  88 
  89     if (!auxiliaryThreadNotified) {
  90         NSK_COMPLAIN1("%s: Error happenned during auxiliary thread notification, test may hang\n", agentName);
  91     }
  92 }
  93 
  94 void JNICALL auxiliaryThreadFunction(jvmtiEnv* jvmti, JNIEnv* jni, void* arg) {
  95     NSK_DISPLAY1("%s: auxiliary thread is running\n", agentName);
  96 
  97     if (NSK_JVMTI_VERIFY(jvmti->RawMonitorEnter(gcFinishMonitor))) {
  98 
  99         if (!gcFinishEventReceived) {
 100             if (!NSK_JVMTI_VERIFY(jvmti->RawMonitorWait(gcFinishMonitor, 0))) {
 101                 success = 0;
 102             }
 103         }
 104 
 105         if (!NSK_JVMTI_VERIFY(jvmti->RawMonitorExit(gcFinishMonitor))) {
 106             success = 0;
 107         }
 108     } else {
 109         success = 0;
 110     }
 111 
 112     nsk_jvmti_aod_disableEventsAndFinish(agentName, testEvents, testEventsNumber, success, jvmti, jni);
 113 }
 114 
 115 int startAuxiliaryThread(jvmtiEnv* jvmti, JNIEnv* jni) {
 116     jthread thread;
 117 
 118     thread = nsk_jvmti_aod_createThread(jni);
 119     if (!NSK_VERIFY(thread != NULL))
 120         return NSK_FALSE;
 121 
 122     if (!NSK_JVMTI_VERIFY(jvmti->RunAgentThread(thread, auxiliaryThreadFunction, NULL, JVMTI_THREAD_NORM_PRIORITY))) {
 123         return NSK_FALSE;
 124     }
 125 
 126     NSK_DISPLAY1("%s: auxiliary thread was started\n", agentName);
 127 
 128     return NSK_TRUE;
 129 }
 130 
 131 #ifdef STATIC_BUILD
 132 JNIEXPORT jint JNI_OnLoad_attach020Agent00(JavaVM *jvm, char *options, void *reserved) {
 133     return JNI_VERSION_1_8;
 134 }
 135 #endif
 136 
 137 JNIEXPORT jint JNICALL
 138 #ifdef STATIC_BUILD
 139 Agent_OnAttach_attach020Agent00(JavaVM *vm, char *optionsString, void *reserved)
 140 #else
 141 Agent_OnAttach(JavaVM *vm, char *optionsString, void *reserved)
 142 #endif
 143 {
 144     jvmtiEnv* jvmti;
 145     jvmtiEventCallbacks eventCallbacks;
 146     jvmtiCapabilities caps;
 147     JNIEnv* jni;
 148 
 149     options = (Options*) nsk_aod_createOptions(optionsString);
 150     if (!NSK_VERIFY(options != NULL))
 151         return JNI_ERR;
 152 
 153     agentName = nsk_aod_getOptionValue(options, NSK_AOD_AGENT_NAME_OPTION);
 154 
 155     jni = (JNIEnv*) nsk_aod_createJNIEnv(vm);
 156     if (jni == NULL)
 157         return JNI_ERR;
 158 
 159     jvmti = nsk_jvmti_createJVMTIEnv(vm, reserved);
 160     if (!NSK_VERIFY(jvmti != NULL))
 161         return JNI_ERR;
 162 
 163     if (!NSK_JVMTI_VERIFY(jvmti->CreateRawMonitor("GCFinishMonitor", &gcFinishMonitor))) {
 164         return JNI_ERR;
 165     }
 166 
 167     if (!NSK_VERIFY(startAuxiliaryThread(jvmti, jni)))
 168         return JNI_ERR;
 169 
 170     memset(&caps, 0, sizeof(caps));
 171     caps.can_generate_garbage_collection_events = 1;
 172     if (!NSK_JVMTI_VERIFY(jvmti->AddCapabilities(&caps))) {
 173         return JNI_ERR;
 174     }
 175 
 176     memset(&eventCallbacks,0, sizeof(eventCallbacks));
 177     eventCallbacks.GarbageCollectionStart  = garbageCollectionStartHandler;
 178     eventCallbacks.GarbageCollectionFinish = garbageCollectionFinishHandler;
 179     if (!NSK_JVMTI_VERIFY(jvmti->SetEventCallbacks(&eventCallbacks, sizeof(eventCallbacks)))) {
 180         return JNI_ERR;
 181     }
 182 
 183     if (!(nsk_jvmti_aod_enableEvents(jvmti, testEvents, testEventsNumber))) {
 184         return JNI_ERR;
 185     }
 186 
 187     NSK_DISPLAY1("%s: initialization was done\n", agentName);
 188 
 189     if (!NSK_VERIFY(nsk_aod_agentLoaded(jni, agentName)))
 190         return JNI_ERR;
 191 
 192     return JNI_OK;
 193 }
 194 }