test/hotspot/jtreg/vmTestbase/nsk/jvmti/ForceGarbageCollection/forcegc002/forcegc002.c

/*
 * Copyright (c) 2003, 2018, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

#include <string.h>
#include "jvmti.h"
#include "agent_common.h"
#include "jni_tools.h"
#include "jvmti_tools.h"

#ifdef __cplusplus
extern "C" {
#endif

/* ============================================================================= */

static jlong timeout = 0;

static volatile int events = 0;

/* ============================================================================= */

/** Agent algorithm. */
static void JNICALL
agentProc(jvmtiEnv* jvmti, JNIEnv* jni, void* arg) {
    NSK_DISPLAY0("Wait for objects ready for GC\n");
    if (!NSK_VERIFY(nsk_jvmti_waitForSync(timeout)))
        return;

    NSK_DISPLAY0(">>> Testcase #1: force GC to collect unreachable objects\n");
    {
        jvmtiEvent event = JVMTI_EVENT_GARBAGE_COLLECTION_START;

        events = 0;
        NSK_DISPLAY0("Enable event GarbageCollectionStart\n");
        if (!NSK_VERIFY(nsk_jvmti_enableEvents(JVMTI_ENABLE, 1, &event, NULL)))
            return;

        NSK_DISPLAY0("Call ForceGarbageCollection()\n");
        if (!NSK_JVMTI_VERIFY(
                NSK_CPP_STUB1(ForceGarbageCollection, jvmti))) {
            nsk_jvmti_setFailStatus();
            return;
        }

        NSK_DISPLAY0("Disable event GarbageCollectionStart\n");
        if (!NSK_VERIFY(nsk_jvmti_enableEvents(JVMTI_DISABLE, 1, &event, NULL)))
            return;

        NSK_DISPLAY0("Check if expected events received\n");
        NSK_DISPLAY1("    received: %d events\n", events);
        if (events <= 0) {
            NSK_DISPLAY0("#WARNING: no GarbageCollectionStart events received for ForceGarbageCollection()\n");
        }
    }

    NSK_DISPLAY0("Let debugee to finish\n");
    if (!NSK_VERIFY(nsk_jvmti_resumeSync()))
        return;
}

/* ============================================================================= */

JNIEXPORT void JNICALL
callbackGarbageCollectionStart(jvmtiEnv* jvmti) {
    NSK_DISPLAY0("    event: GarbageCollectionStart\n");
    events++;
}

/* ============================================================================= */

/** Agent library initialization. */
#ifdef STATIC_BUILD
JNIEXPORT jint JNICALL Agent_OnLoad_forcegc002(JavaVM *jvm, char *options, void *reserved) {
    return Agent_Initialize(jvm, options, reserved);
}
JNIEXPORT jint JNICALL Agent_OnAttach_forcegc002(JavaVM *jvm, char *options, void *reserved) {
    return Agent_Initialize(jvm, options, reserved);
}
JNIEXPORT jint JNI_OnLoad_forcegc002(JavaVM *jvm, char *options, void *reserved) {
    return JNI_VERSION_1_8;
}
#endif
jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved) {
    jvmtiEnv* jvmti = NULL;

    if (!NSK_VERIFY(nsk_jvmti_parseOptions(options)))
        return JNI_ERR;

    timeout = nsk_jvmti_getWaitTime() * 60 * 1000;

    if (!NSK_VERIFY((jvmti =
            nsk_jvmti_createJVMTIEnv(jvm, reserved)) != NULL))
        return JNI_ERR;

    {
        jvmtiCapabilities caps;
        memset(&caps, 0, sizeof(caps));
        caps.can_generate_garbage_collection_events = 1;
        if (!NSK_JVMTI_VERIFY(NSK_CPP_STUB2(AddCapabilities, jvmti, &caps)))
            return JNI_ERR;
    }

    {
        jvmtiEventCallbacks eventCallbacks;
        memset(&eventCallbacks, 0, sizeof(eventCallbacks));
        eventCallbacks.GarbageCollectionStart = callbackGarbageCollectionStart;
        if (!NSK_JVMTI_VERIFY(
                NSK_CPP_STUB3(SetEventCallbacks, jvmti,
                                    &eventCallbacks, sizeof(eventCallbacks))))
            return JNI_ERR;
    }

    if (!NSK_VERIFY(nsk_jvmti_setAgentProc(agentProc, NULL)))
        return JNI_ERR;

    return JNI_OK;
}

/* ============================================================================= */

#ifdef __cplusplus
}
#endif