/*

 * 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 <stdio.h>

#include <string.h>

#include "jvmti.h"

#include "agent_common.h"

#include "JVMTITools.h"

#ifdef __cplusplus

extern "C" {

#endif

#ifndef JNI_ENV_ARG

#ifdef __cplusplus

#define JNI_ENV_ARG(x, y) y

#define JNI_ENV_PTR(x) x

#else

#define JNI_ENV_ARG(x,y) x, y

#define JNI_ENV_PTR(x) (*x)

#endif

#endif

#define PASSED 0

#define STATUS_FAILED 2

static jvmtiEnv *jvmti = NULL;

static jvmtiCapabilities caps;

static jint result = PASSED;

static jboolean printdump = JNI_FALSE;

#ifdef STATIC_BUILD

JNIEXPORT jint JNICALL Agent_OnLoad_redefclass024(JavaVM *jvm, char *options, void *reserved) {

    return Agent_Initialize(jvm, options, reserved);

}

JNIEXPORT jint JNICALL Agent_OnAttach_redefclass024(JavaVM *jvm, char *options, void *reserved) {

    return Agent_Initialize(jvm, options, reserved);

}

JNIEXPORT jint JNI_OnLoad_redefclass024(JavaVM *jvm, char *options, void *reserved) {

    return JNI_VERSION_1_8;

}

#endif

jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved) {

    jint res;

    jvmtiError err;

    if (options != NULL && strcmp(options, "printdump") == 0) {

        printdump = JNI_TRUE;

    }

    res = JNI_ENV_PTR(jvm)->GetEnv(JNI_ENV_ARG(jvm, (void **) &jvmti),

        JVMTI_VERSION_1_1);

    if (res != JNI_OK || jvmti == NULL) {

        printf("Wrong result of a valid call to GetEnv!\n");

        return JNI_ERR;

    }

    if (err != JVMTI_ERROR_NONE) {

        printf("(GetPotentialCapabilities) unexpected error: %s (%d)\n",

               TranslateError(err), err);

        return JNI_ERR;

    }

    if (err != JVMTI_ERROR_NONE) {

        printf("(AddCapabilities) unexpected error: %s (%d)\n",

               TranslateError(err), err);

        return JNI_ERR;

    }

    if (err != JVMTI_ERROR_NONE) {

        printf("(GetCapabilities) unexpected error: %s (%d)\n",

               TranslateError(err), err);

        return JNI_ERR;

    }

    if (!caps.can_redefine_classes) {

        printf("Warning: RedefineClasses is not implemented\n");

    }

    return JNI_OK;

}

JNIEXPORT jint JNICALL

Java_nsk_jvmti_RedefineClasses_redefclass024_check(JNIEnv *env, jclass cls,

         jclass clazz, jbyteArray bytes) {

    jvmtiError err;

    jvmtiClassDefinition classDef;

    if (jvmti == NULL) {

        printf("JVMTI client was not properly loaded!\n");

        return STATUS_FAILED;

    }

    classDef.klass = clazz;

    classDef.class_byte_count =

        JNI_ENV_PTR(env)->GetArrayLength(JNI_ENV_ARG(env, bytes));

    classDef.class_bytes = (unsigned char *)

        JNI_ENV_PTR(env)->GetByteArrayElements(JNI_ENV_ARG(env, bytes), NULL);

    if (printdump == JNI_TRUE) {

        printf(">>> change class modifiers capability check ...\n");

    }

    if (err == JVMTI_ERROR_MUST_POSSESS_CAPABILITY &&

            !caps.can_redefine_classes) {

        /* It is OK */

    } else

        if (err != JVMTI_ERROR_UNSUPPORTED_REDEFINITION_CLASS_MODIFIERS_CHANGED) {

            printf("Warning: RedefineClasses is restricted\n");

            printf("Error expected: ");

            printf("JVMTI_ERROR_UNSUPPORTED_REDEFINITION_CLASS_MODIFIERS_CHANGED,\n");

            printf("\tactual: %s (%d)\n", TranslateError(err), err);

            result = STATUS_FAILED;

        }

    if (printdump == JNI_TRUE) {

        printf(">>> ... done\n");

    }

    return result;

}

#ifdef __cplusplus

}

#endif