test/hotspot/jtreg/vmTestbase/nsk/jvmti/scenarios/hotswap/HS104/hs104t001/hs104t001.c

/*
 * Copyright (c) 2007, 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 <jni.h>
#include <jvmti.h>
#include "agent_common.h"
#include <string.h>
#include "jvmti_tools.h"
#include "JVMTITools.h"


#ifdef __cplusplus
extern "C" {
#endif

#define FILE_NAME "nsk/jvmti/scenarios/hotswap/HS104/hs104t001/MyClass"
#define CLASS_NAME "Lnsk/jvmti/scenarios/hotswap/HS104/hs104t001/MyClass;"

JNIEXPORT void JNICALL
    callbackClassPrepare(jvmtiEnv *jvmti,
            JNIEnv* jni,
            jthread thread,
            jclass klass) {

    char * className;
    char * generic;
    (*jvmti)->GetClassSignature(jvmti, klass, &className, &generic);
    if (strcmp(className, CLASS_NAME) == 0) {
        char fileName[512];
        nsk_jvmti_getFileName(0, FILE_NAME, fileName,
                        sizeof(fileName)/sizeof(char));
        if ( nsk_jvmti_redefineClass(jvmti, klass, fileName ) == NSK_TRUE ) {
            nsk_printf("Agent:: Successfully redefined..");
            if ( nsk_jvmti_disableNotification(jvmti,JVMTI_EVENT_CLASS_PREPARE, NULL) == NSK_TRUE ) {
                nsk_printf(" Agent :: NOTIFICATIONS ARE DISABLED \n");
            } else {
                nsk_printf(" Agent :: Failed to disabled \n");
            }
        } else {
            nsk_printf("Agent:: Failed to redefine..");
        }
    }
}

#ifdef STATIC_BUILD
JNIEXPORT jint JNICALL Agent_OnLoad_hs104t001(JavaVM *jvm, char *options, void *reserved) {
    return Agent_Initialize(jvm, options, reserved);
}
JNIEXPORT jint JNICALL Agent_OnAttach_hs104t001(JavaVM *jvm, char *options, void *reserved) {
    return Agent_Initialize(jvm, options, reserved);
}
JNIEXPORT jint JNI_OnLoad_hs104t001(JavaVM *jvm, char *options, void *reserved) {
    return JNI_VERSION_1_8;
}
#endif
jint  Agent_Initialize(JavaVM *vm, char *options, void *reserved) {
    jint rc ;
    jvmtiEnv * jvmti;
    nsk_printf("Agent:: VM.. Started..\n");
    rc=(*vm)->GetEnv(vm, (void **)&jvmti, JVMTI_VERSION_1_1);
    if ( rc!= JNI_OK ) {
        nsk_printf("Agent:: Could not load JVMTI interface \n");
        return JNI_ERR;
    } else {
        jvmtiCapabilities caps;
        jvmtiEventCallbacks eventCallbacks;
        if (nsk_jvmti_parseOptions(options) == NSK_FALSE ) {
            nsk_printf("# error agent Failed to parse options \n");
            return JNI_ERR;
        }
        memset(&caps, 0, sizeof(caps));
        caps.can_redefine_classes = 1;
        caps.can_generate_all_class_hook_events = 1;
        (*jvmti)->AddCapabilities(jvmti, &caps);
        memset(&eventCallbacks, 0, sizeof(eventCallbacks));
        eventCallbacks.ClassPrepare =callbackClassPrepare;
        rc=(*jvmti)->SetEventCallbacks(jvmti,&eventCallbacks, sizeof(eventCallbacks));
        if (rc != JVMTI_ERROR_NONE) {
            nsk_printf(" Agent:: Error occured while setting event call back \n");
            return JNI_ERR;
        }
        if ( nsk_jvmti_enableNotification(jvmti,
                    JVMTI_EVENT_CLASS_PREPARE, NULL) == NSK_TRUE ) {
            nsk_printf("Agent :: NOTIFICATIONS ARE ENABLED \n");
        } else {
            nsk_printf(" Error in Eanableing Notifications..");
        }
    }
    return JNI_OK;
}

#ifdef __cplusplus
}
#endif