/*

 * 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"

extern "C" {

#define STATUS_FAILED 2

#define PASSED 0

static jvmtiEnv *jvmti = NULL;

static jvmtiCapabilities caps;

static jvmtiEventCallbacks callbacks;

static int watch_ev = 0;    /* ignore JVMTI events by default */

static int CFLH_gen_ev = 0; /* number of generated ClassFileLoadHook events */

static int gen_ev = 0;      /* number of generated events */

static int result = PASSED; /* total result of the test */

static jrawMonitorID watch_ev_monitor;

static void set_watch_ev(int value) {

    jvmti->RawMonitorEnter(watch_ev_monitor);

    watch_ev = value;

    jvmti->RawMonitorExit(watch_ev_monitor);

}

void JNICALL

ClassFileLoadHook(jvmtiEnv *jvmti_env, JNIEnv *env, jclass class_being_redefined,

        jobject loader, const char* name, jobject protection_domain,

        jint class_data_len, const unsigned char* class_data,

        jint *new_class_data_len, unsigned char** new_class_data) {

    jvmti->RawMonitorEnter(watch_ev_monitor);

    if (watch_ev && class_being_redefined != NULL) {

        printf("#### JVMTI_EVENT_CLASS_FILE_LOAD_HOOK occurred ####\n");

        CFLH_gen_ev++;

    }

    jvmti->RawMonitorExit(watch_ev_monitor);

}

void JNICALL

ClassLoad(jvmtiEnv *jvmti_env, JNIEnv *env, jthread thr, jclass cls) {

    jvmti->RawMonitorEnter(watch_ev_monitor);

    if (watch_ev) {

        printf("#### JVMTI_EVENT_CLASS_LOAD occurred ####\n");

        gen_ev++;

    }

    jvmti->RawMonitorExit(watch_ev_monitor);

}

void JNICALL

ClassPrepare(jvmtiEnv *jvmti_env, JNIEnv *env, jthread thr, jclass cls) {

    jvmti->RawMonitorEnter(watch_ev_monitor);

    if (watch_ev) {

        printf("#### JVMTI_EVENT_CLASS_PREPARE occurred ####\n");

        gen_ev++;

    }

    jvmti->RawMonitorExit(watch_ev_monitor);

}

#ifdef STATIC_BUILD

JNIEXPORT jint JNICALL Agent_OnLoad_redefclass005(JavaVM *jvm, char *options, void *reserved) {

    return Agent_Initialize(jvm, options, reserved);

}

JNIEXPORT jint JNICALL Agent_OnAttach_redefclass005(JavaVM *jvm, char *options, void *reserved) {

    return Agent_Initialize(jvm, options, reserved);

}

JNIEXPORT jint JNI_OnLoad_redefclass005(JavaVM *jvm, char *options, void *reserved) {

    return JNI_VERSION_1_8;

}

#endif

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

    jint res;

    jvmtiError err;

        printf("%s: Failed to call GetEnv: error=%d\n", __FILE__, res);

        return JNI_ERR;

    }

    err = jvmti->GetPotentialCapabilities(&caps);

    if (err != JVMTI_ERROR_NONE) {

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

               TranslateError(err), err);

        return JNI_ERR;

    }

    err = jvmti->AddCapabilities(&caps);

    if (err != JVMTI_ERROR_NONE) {

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

               TranslateError(err), err);

        return JNI_ERR;

    }

    err = jvmti->GetCapabilities(&caps);

    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");

    }

    callbacks.ClassFileLoadHook = &ClassFileLoadHook;

    callbacks.ClassLoad = &ClassLoad;

    callbacks.ClassPrepare = &ClassPrepare;

    err = jvmti->SetEventCallbacks(&callbacks, sizeof(callbacks));

    if (err != JVMTI_ERROR_NONE) {

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

               TranslateError(err), err);

        return JNI_ERR;

    }

    err = jvmti->CreateRawMonitor("watch_ev_monitor", &watch_ev_monitor);

    if (err != JVMTI_ERROR_NONE) {

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

               TranslateError(err), err);

        return JNI_ERR;

    }

    return JNI_OK;

}

JNIEXPORT jint JNICALL

Java_nsk_jvmti_RedefineClasses_redefclass005_makeRedefinition(JNIEnv *env,

        jclass cls, jint vrb, jclass redefCls, jbyteArray classBytes) {

    jvmtiError err;

    jthread thread;

    jvmtiClassDefinition classDef;

    if (jvmti == NULL) {

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

        return STATUS_FAILED;

    }

    if (!caps.can_redefine_classes) {

        return PASSED;

    }

        printf("Failed to get current thread: %s (%d)\n", TranslateError(err), err);

        result = STATUS_FAILED;

        return STATUS_FAILED;

    }

        printf("Failed to enable event JVMTI_EVENT_CLASS_FILE_LOAD_HOOK: %s (%d)\n",

               TranslateError(err), err);

        result = STATUS_FAILED;

    }

        printf("Failed to enable event JVMTI_EVENT_CLASS_LOAD: %s (%d)\n",

               TranslateError(err), err);

        result = STATUS_FAILED;

    }

        printf("Failed to enable JVMTI_EVENT_CLASS_PREPARE: %s (%d)\n",

               TranslateError(err), err);

        result = STATUS_FAILED;

    }

/* filling the structure jvmtiClassDefinition */

    classDef.klass = redefCls;

    classDef.class_byte_count = env->GetArrayLength(classBytes);

    classDef.class_bytes = (unsigned char *) env->GetByteArrayElements(classBytes, NULL);

    set_watch_ev(1); /* watch JVMTI events */

    if (vrb == 1)

        printf(">>>>>>>> Invoke RedefineClasses():\n\tnew class byte count=%d\n",

            classDef.class_byte_count);

        printf("TEST FAILED: the function RedefineClasses() returned error %d: %s\n",

            err, TranslateError(err));

        printf("\tFor more info about this error see the JVMTI spec.\n");

        result = STATUS_FAILED;

    }

    else if (vrb == 1)

        printf("Check #1 PASSED: RedefineClasses() is successfully done\n");

    set_watch_ev(0); /* again ignore JVMTI events */

    if (CFLH_gen_ev == 0) {

        printf("TEST FAILED: ClassFileLoadHook event was not generated by the function RedefineClasses()\n");

        result = STATUS_FAILED;

    } else if (vrb == 1)

        printf("Check #2 PASSED: %d ClassFileLoadHook events were generated by the function RedefineClasses()\n",

            CFLH_gen_ev);

    if (gen_ev) {

        printf("TEST FAILED: %d unexpected JVMTI events were generated by the function RedefineClasses()\n",

            gen_ev);

        result = STATUS_FAILED;

    } else if (vrb == 1)

        printf("Check #2 PASSED: No unexpected JVMTI events were generated by the function RedefineClasses()\n");

    return(result);

}

}