/*

 * Copyright (c) 2004, 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 <stdlib.h>

#include <string.h>

#include "jni_tools.h"

#include "agent_common.h"

#include "jvmti_tools.h"

#define PASSED 0

#define STATUS_FAILED 2

#ifdef __cplusplus

extern "C" {

#endif

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

/* scaffold objects */

static jlong timeout = 0;

/* test objects */

static jint klass_byte_count = 0;

static unsigned char *klass_bytes = NULL;

static int ClassFileLoadHookEventFlag = NSK_FALSE;

const char* CLASS_NAME = "nsk/jvmti/scenarios/multienv/MA07/ma07t001a";

static const jint magicNumber_1 = 0x12345678;

static const jint magicNumber_2 = (jint)0x87654321;

static const unsigned char newMagicNumber = 0x1;

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

/** callback functions **/

static void JNICALL

ClassFileLoadHook(jvmtiEnv *jvmti_env, JNIEnv *jni_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) {

    int found_1 = NSK_FALSE;

    int found_2 = NSK_FALSE;

    jint magicIndex = 0;

    jint i;

    if (name != NULL && (strcmp(name, CLASS_NAME) == 0)) {

        ClassFileLoadHookEventFlag = NSK_TRUE;

        NSK_DISPLAY0("ClassFileLoadHook event\n");

        if (!NSK_VERIFY(class_being_redefined == NULL)) {

            nsk_jvmti_setFailStatus();

            return;

        }

        if (!NSK_JVMTI_VERIFY(NSK_CPP_STUB3(Allocate,

                jvmti_env, class_data_len, &klass_bytes)))

            nsk_jvmti_setFailStatus();

        else {

            memcpy(klass_bytes, class_data, class_data_len);

            klass_byte_count = class_data_len;

            for (i = 0; i < klass_byte_count - 3; i++) {

                if (((jint)klass_bytes[i+3] |

                    ((jint)klass_bytes[i+2] << 8) |

                    ((jint)klass_bytes[i+1] << 16) |

                    ((jint)klass_bytes[i] << 24)) == magicNumber_1) {

                    NSK_DISPLAY2("index of 0x%x: %d\n", magicNumber_1, i);

                    found_1 = NSK_TRUE;

                    magicIndex = i;

                } else if (((jint)klass_bytes[i+3] |

                    ((jint)klass_bytes[i+2] << 8) |

                    ((jint)klass_bytes[i+1] << 16) |

                    ((jint)klass_bytes[i] << 24)) == magicNumber_2) {

                    NSK_DISPLAY2("index of 0x%x: %d\n", magicNumber_2, i);

                    found_2 = NSK_TRUE;

                }

            }

            if (!NSK_VERIFY(found_1)) {

                NSK_COMPLAIN1("magic number 0x%x not found\n", magicNumber_1);

                nsk_jvmti_setFailStatus();

            }

            if (!NSK_VERIFY(found_2)) {

                NSK_COMPLAIN1("magic number 0x%x not found\n", magicNumber_2);

                nsk_jvmti_setFailStatus();

            }

            if (found_1) {

                NSK_DISPLAY1("Instrumenting with %d\n", newMagicNumber);

                klass_bytes[magicIndex] = 0;

                klass_bytes[magicIndex+1] = 0;

                klass_bytes[magicIndex+2] = 0;

                klass_bytes[magicIndex+3] = newMagicNumber;

                *new_class_data = klass_bytes;

                *new_class_data_len = klass_byte_count;

            }

        }

    }

}

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

/** Agent algorithm. */

static void JNICALL

agentProc(jvmtiEnv* jvmti, JNIEnv* jni, void* arg) {

    if (!nsk_jvmti_waitForSync(timeout))

        return;

    if (!NSK_VERIFY(ClassFileLoadHookEventFlag)) {

        NSK_COMPLAIN0("Missing ClassFileLoadHook event\n");

        nsk_jvmti_setFailStatus();

    }

    if (!nsk_jvmti_resumeSync())

        return;

}

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

/** Agent library initialization. */

#ifdef STATIC_BUILD

JNIEXPORT jint JNICALL Agent_OnLoad_ma07t001(JavaVM *jvm, char *options, void *reserved) {

    return Agent_Initialize(jvm, options, reserved);

}

JNIEXPORT jint JNICALL Agent_OnAttach_ma07t001(JavaVM *jvm, char *options, void *reserved) {

    return Agent_Initialize(jvm, options, reserved);

}

JNIEXPORT jint JNI_OnLoad_ma07t001(JavaVM *jvm, char *options, void *reserved) {

    return JNI_VERSION_1_8;

}

#endif

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

    jvmtiEnv* jvmti = NULL;

    jvmtiEventCallbacks callbacks;

    NSK_DISPLAY0("Agent_OnLoad\n");

    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;

    if (!NSK_VERIFY(nsk_jvmti_setAgentProc(agentProc, NULL)))

        return JNI_ERR;

    memset(&callbacks, 0, sizeof(callbacks));

    callbacks.ClassFileLoadHook = &ClassFileLoadHook;

    if (!NSK_VERIFY(nsk_jvmti_init_MA(&callbacks)))

        return JNI_ERR;

    if (!NSK_JVMTI_VERIFY(NSK_CPP_STUB4(SetEventNotificationMode,

            jvmti, JVMTI_ENABLE, JVMTI_EVENT_CLASS_FILE_LOAD_HOOK, NULL)))

        return JNI_ERR;

    return JNI_OK;

}

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

#ifdef __cplusplus

}

#endif