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 #ifdef __cplusplus

    32 extern "C" {

    33 #endif

    34 

    35 /*

    36  * Expected agent work scenario:

    37  *  - during initialization agent enables ThreadStart events

    38  *  - target application starts thread

    39  *  - agent receives ThreadStart event and tries to find thread provoked this event

    40  *    in all VM thread groups and finishes work

    41  */

    42 

    43 #define STARTED_TEST_THREAD_NAME "attach041-TestThread"

    44 

    45 static Options* options = NULL;

    46 static const char* agentName;

    47 

    48 int tryFindThread(jvmtiEnv *jvmti, jthreadGroup group, const char* threadNameToFind) {

    49     jint threadsCount = 0;

    50     jthread *threads = NULL;

    51     jint groupsCount = 0;

    52     jthreadGroup* groups = NULL;

    53     jvmtiThreadGroupInfo groupInfo;

    54     int i;

    55     char threadGroupName[MAX_STRING_LENGTH];

    56 

    57     if(!NSK_JVMTI_VERIFY(NSK_CPP_STUB3(GetThreadGroupInfo, jvmti, group, &groupInfo))) {

    58         return 0;

    59     }

    60 

    61     strcpy(threadGroupName, groupInfo.name);

    62     nsk_jvmti_aod_deallocate(jvmti, (unsigned char*)groupInfo.name);

    63 

    64     NSK_DISPLAY3("%s: trying to find thread '%s' in group '%s'\n", agentName, threadNameToFind, threadGroupName);

    65 

    66     if(!NSK_JVMTI_VERIFY(NSK_CPP_STUB6(GetThreadGroupChildren, jvmti, group, &threadsCount, &threads, &groupsCount, &groups))) {

    67         return 0;

    68     }

    69 

    70     for (i = 0; i < threadsCount; i++) {

    71         char threadName[MAX_STRING_LENGTH];

    72         if (!nsk_jvmti_aod_getThreadName(jvmti, threads[i], threadName)) {

    73             NSK_COMPLAIN1("%s: failed to get thread name\n", agentName);

    74             nsk_jvmti_aod_deallocate(jvmti, (unsigned char*)threads);

    75             return 0;

    76         }

    77         if (!strcmp(threadName, threadNameToFind)) {

    78             nsk_jvmti_aod_deallocate(jvmti, (unsigned char*)threads);

    79             nsk_jvmti_aod_deallocate(jvmti, (unsigned char*)groups);

    80             NSK_DISPLAY3("%s: thread '%s' was found in group '%s'\n", agentName, threadNameToFind, threadGroupName);

    81             return 1;

    82         }

    83     }

    84 

    85     // threads array isn't needed more

    86     nsk_jvmti_aod_deallocate(jvmti, (unsigned char*)threads);

    87 

    88     NSK_DISPLAY3("%s: thread '%s' wasn't found in group '%s'\n", agentName, threadNameToFind, threadGroupName);

    89 

    90     if (groupsCount != 0) {

    91         for (i = 0; i < groupsCount; i++) {

    92             if (tryFindThread(jvmti, groups[i], threadNameToFind)) {

    93                 nsk_jvmti_aod_deallocate(jvmti, (unsigned char*)groups);

    94                 return 1;

    95             }

    96         }

    97     }

    98 

    99     nsk_jvmti_aod_deallocate(jvmti, (unsigned char*)groups);

   100 

   101     return 0;

   102 }

   103 

   104 void JNICALL threadStartHandler(jvmtiEnv *jvmti,

   105         JNIEnv* jni,

   106         jthread thread) {

   107     char startedThreadName[MAX_STRING_LENGTH];

   108 

   109     if (!nsk_jvmti_aod_getThreadName(jvmti, thread, startedThreadName)) {

   110         nsk_jvmti_aod_disableEventAndFinish(agentName, JVMTI_EVENT_THREAD_START, 0, jvmti, jni);

   111         return;

   112     }

   113 

   114     NSK_DISPLAY2("%s: ThreadStart event was received for thread '%s'\n", agentName, startedThreadName);

   115 

   116     if (!strcmp(startedThreadName, STARTED_TEST_THREAD_NAME)) {

   117         int success = 1;

   118         int threadWasFound = 0;

   119         jint groupsCount = 0;

   120         jthreadGroup *topGroups;

   121         int i;

   122 

   123         if(!NSK_JVMTI_VERIFY(NSK_CPP_STUB3(GetTopThreadGroups, jvmti, &groupsCount, &topGroups))) {

   124             NSK_COMPLAIN1("%s: failed to get top thread groups\n", agentName);

   125             nsk_jvmti_aod_disableEventAndFinish(agentName, JVMTI_EVENT_THREAD_START, 0, jvmti, jni);

   126             return;

   127         }

   128 

   129         for (i = 0; i < groupsCount; i++) {

   130             if (tryFindThread(jvmti, topGroups[i], startedThreadName)) {

   131                 threadWasFound = 1;

   132                 break;

   133             }

   134         }

   135 

   136         nsk_jvmti_aod_deallocate(jvmti, (unsigned char*)topGroups);

   137 

   138         if (!threadWasFound) {

   139             success = 0;

   140             NSK_COMPLAIN2("%s: failed to find thread '%s'\n", agentName, startedThreadName);

   141         }

   142 

   143         nsk_jvmti_aod_disableEventAndFinish(agentName, JVMTI_EVENT_THREAD_START, success, jvmti, jni);

   144     }

   145 }

   146 

   147 #ifdef STATIC_BUILD

   148 JNIEXPORT jint JNI_OnLoad_attach041Agent00(JavaVM *jvm, char *options, void *reserved) {

   149     return JNI_VERSION_1_8;

   150 }

   151 #endif

   152 

   153 JNIEXPORT jint JNICALL

   154 #ifdef STATIC_BUILD

   155 Agent_OnAttach_attach041Agent00(JavaVM *vm, char *optionsString, void *reserved)

   156 #else

   157 Agent_OnAttach(JavaVM *vm, char *optionsString, void *reserved)

   158 #endif

   159 {

   160     jvmtiEventCallbacks eventCallbacks;

   161     jvmtiEnv* jvmti;

   162     JNIEnv* jni;

   163 

   164     if (!NSK_VERIFY((options = (Options*) nsk_aod_createOptions(optionsString)) != NULL))

   165         return JNI_ERR;

   166 

   167     agentName = nsk_aod_getOptionValue(options, NSK_AOD_AGENT_NAME_OPTION);

   168 

   169     if ((jni = (JNIEnv*) nsk_aod_createJNIEnv(vm)) == NULL)

   170         return JNI_ERR;

   171 

   172     if (!NSK_VERIFY((jvmti = nsk_jvmti_createJVMTIEnv(vm, reserved)) != NULL))

   173         return JNI_ERR;

   174 

   175     memset(&eventCallbacks,0, sizeof(eventCallbacks));

   176     eventCallbacks.ThreadStart = threadStartHandler;

   177     if (!NSK_JVMTI_VERIFY(NSK_CPP_STUB3(SetEventCallbacks, jvmti, &eventCallbacks, sizeof(eventCallbacks))) ) {

   178         return JNI_ERR;

   179     }

   180 

   181     if (!(nsk_jvmti_aod_enableEvent(jvmti, JVMTI_EVENT_THREAD_START))) {

   182         return JNI_ERR;

   183     }

   184 

   185     NSK_DISPLAY1("%s: initialization was done\n", agentName);

   186 

   187     if (!NSK_VERIFY(nsk_aod_agentLoaded(jni, agentName)))

   188         return JNI_ERR;

   189 

   190     return JNI_OK;

   191 }

   192 

   193 #ifdef __cplusplus

   194 }

   195 #endif