/*

 * 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 <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <jvmti.h>

#include "agent_common.h"

#include <jni.h>

#include "jvmti_tools.h"

#include "jni_tools.h"

#include "JVMTITools.h"

extern "C" {

#define FILE_NAME "nsk/jvmti/scenarios/hotswap/HS204/hs204t003/MyThread"

#define CLASS_NAME  "Lnsk/jvmti/scenarios/hotswap/HS204/hs204t003/MyThread;"

#define FIELDNAME "intState"

#define TYPE "I"

static jint redefineNumber;

static jvmtiEnv * jvmti;

static jclass watchFieldClass;

JNIEXPORT void JNICALL callbackClassPrepare(jvmtiEnv *jvmti_env,

        JNIEnv* jni,

        jthread thread,

        jclass klass) {

    char * className;

    char * generic;

    className = NULL;

    generic   = NULL;

    redefineNumber=0;

    if (!NSK_JVMTI_VERIFY(jvmti_env->GetClassSignature(klass, &className, &generic))) {

        NSK_DISPLAY0(" Agent :: Failed get class signature.\n");

        nsk_jvmti_agentFailed();

    } else {

        if ((strcmp(className, CLASS_NAME) == 0)) {

            jfieldID fieldId;

            if (!NSK_JNI_VERIFY(jni, (fieldId = jni->GetStaticFieldID(klass, FIELDNAME, TYPE)) != NULL)) {

                    NSK_DISPLAY0(" Agent :: Failed to get FieldId.\n");

                    nsk_jvmti_agentFailed();

            } else {

                if (!NSK_JVMTI_VERIFY(jvmti_env->SetFieldAccessWatch(klass, fieldId))) {

                    NSK_DISPLAY0(" Agent :: Failed to set watch point on a field.\n");

                    nsk_jvmti_agentFailed();

                } else {

                    nsk_jvmti_enableNotification(jvmti_env, JVMTI_EVENT_FIELD_ACCESS, NULL);

                    if (!NSK_JNI_VERIFY(jni, (watchFieldClass = (jclass) jni->NewGlobalRef(klass)) != NULL)) {

                        NSK_DISPLAY0(" Agent :: Failed to get global reference for class.\n");

                        nsk_jvmti_agentFailed();

                    }

                    NSK_DISPLAY0(" Agent :: SetFieldAccessWatch.\n");

                }

            }

            NSK_DISPLAY1(" Agent :: Leaving callbackClassPrepare for class = %s .\n", className);

        }

    }

    if (className != NULL) {

        if (!NSK_JVMTI_VERIFY(jvmti_env->Deallocate((unsigned char *)className))) {

            NSK_DISPLAY1(" Agent :: #error failed to Deallocate className = %s.", className);

            nsk_jvmti_agentFailed();

        }

    }

    if (generic != NULL) {

        if (!NSK_JVMTI_VERIFY(jvmti_env->Deallocate((unsigned char *)generic))) {

            NSK_DISPLAY1(" Agent :: #error failed to Deallocate class signature = %s.", generic);

            nsk_jvmti_agentFailed();

        }

    }

    return;

}

JNIEXPORT void JNICALL callbackFieldAccess(jvmtiEnv *jvmti_env,

        JNIEnv* jni,

        jthread thread,

        jmethodID method,

        jlocation location,

        jclass field_klass,

        jobject object,

        jfieldID field) {

    char fileName[512];

    char * className;

    char * generic;

    className = NULL;

    generic   = NULL;

    if (redefineNumber != 0) {

        return;

    }

    if (!NSK_JVMTI_VERIFY(jvmti_env->GetClassSignature(field_klass, &className, &generic))) {

        NSK_DISPLAY0(" Agent :: Failed get class signature.\n");

        nsk_jvmti_agentFailed();

    } else {

        if ((strcmp(className, CLASS_NAME) == 0)) {

            jvmtiThreadInfo info;

            nsk_jvmti_getFileName(redefineNumber, FILE_NAME, fileName,

                    sizeof(fileName)/sizeof(char));

                NSK_DISPLAY0(" Agent :: Successfully redefined.\n");

                redefineNumber++;

            } else {

                NSK_DISPLAY0(" Agent :: Failed to redefine.\n");

                nsk_jvmti_agentFailed();

            }

            NSK_DISPLAY0(" Agent :: Before attempting thread suspend.\n");

            if (!NSK_JVMTI_VERIFY(jvmti_env->GetThreadInfo(thread, &info))) {

                NSK_DISPLAY0(" Agent :: error getting thread info ");

                nsk_jvmti_agentFailed();

            } else {

                NSK_DISPLAY1(" Agent :: Thread Name = %s .\n", info.name);

            }

            if (!NSK_JVMTI_VERIFY(jvmti_env->SuspendThread(thread))) {

                NSK_DISPLAY0(" Agent :: Failed to suspend thread.\n");

                nsk_jvmti_agentFailed();

            }

        }

    }

    if (className != NULL) {

        if (!NSK_JVMTI_VERIFY(jvmti_env->Deallocate((unsigned char *)className))) {

            NSK_DISPLAY1(" Agent :: #error failed to Deallocate className = %s.", className);

            nsk_jvmti_agentFailed();

        }

    }

    if (generic != NULL) {

        if (!NSK_JVMTI_VERIFY(jvmti_env->Deallocate((unsigned char *)generic))) {

            NSK_DISPLAY1(" Agent :: #error failed to Deallocate class signature = %s.", generic);

            nsk_jvmti_agentFailed();

        }

    }

}

#ifdef STATIC_BUILD

JNIEXPORT jint JNICALL Agent_OnLoad_hs204t003(JavaVM *jvm, char *options, void *reserved) {

    return Agent_Initialize(jvm, options, reserved);

}

JNIEXPORT jint JNICALL Agent_OnAttach_hs204t003(JavaVM *jvm, char *options, void *reserved) {

    return Agent_Initialize(jvm, options, reserved);

}

JNIEXPORT jint JNI_OnLoad_hs204t003(JavaVM *jvm, char *options, void *reserved) {

    return JNI_VERSION_1_8;

}

#endif

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

    if (!NSK_VERIFY (JNI_OK == vm->GetEnv((void **)&jvmti, JVMTI_VERSION_1_1))) {

        NSK_DISPLAY0("Agent :: Could not load JVMTI interface \n");

        return JNI_ERR;

    } else {

        jvmtiCapabilities caps;

        jvmtiEventCallbacks eventCallbacks;

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

        if (!nsk_jvmti_parseOptions(options)) {

            NSK_DISPLAY0(" NSK Failed to parse..");

            return JNI_ERR;

        }

        caps.can_redefine_classes             = 1;

        caps.can_generate_field_access_events = 1;

        caps.can_pop_frame                    = 1;

        caps.can_suspend                      = 1;

        if (!NSK_JVMTI_VERIFY(jvmti->AddCapabilities(&caps))) {

            NSK_DISPLAY0(" Agent :: Failed add required capabilities\n.");

            return JNI_ERR;

        }

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

        eventCallbacks.ClassPrepare = callbackClassPrepare;

        eventCallbacks.FieldAccess  = callbackFieldAccess;

        if (!NSK_JVMTI_VERIFY(jvmti->SetEventCallbacks(&eventCallbacks, sizeof(eventCallbacks)))) {

            NSK_DISPLAY0(" Agent :: Error occured while setting event call back \n");

            return JNI_ERR;

        }

        nsk_jvmti_enableNotification(jvmti, JVMTI_EVENT_CLASS_PREPARE, NULL);

    }

    return JNI_OK;

}

JNIEXPORT jboolean JNICALL

Java_nsk_jvmti_scenarios_hotswap_HS204_hs204t003_hs204t003_popFrame(JNIEnv * jni,

        jobject object,

        jthread thread) {

    jboolean retvalue;

    jint state;

    retvalue = JNI_FALSE;

    if (!NSK_JVMTI_VERIFY(jvmti->GetThreadState(thread, &state))) {

        NSK_DISPLAY0(" Agent :: Error getting thread state.\n");

        nsk_jvmti_agentFailed();

    } else {

        if (state & JVMTI_THREAD_STATE_SUSPENDED) {

            NSK_DISPLAY0(" Agent :: Thread state = JVMTI_THREAD_STATE_SUSPENDED.\n");

            if (!NSK_JVMTI_VERIFY (jvmti->PopFrame(thread))) {

                NSK_DISPLAY0("#error Agent :: Jvmti failed to do popFrame.\n");

                nsk_jvmti_agentFailed();

            } else {

                if (!NSK_JVMTI_VERIFY (jvmti->ResumeThread(thread))) {

                    NSK_DISPLAY0(" Agent :: Error occured in resuming a thread.\n");

                    nsk_jvmti_agentFailed();

                } else {

                    jfieldID fieldId = jni->GetStaticFieldID(watchFieldClass, FIELDNAME, TYPE);

                    if (!NSK_JNI_VERIFY(jni, fieldId != NULL)) {

                        NSK_DISPLAY0(" Agent :: Failed to get FieldId before droping watchers.\n");

                        nsk_jvmti_agentFailed();

                    } else {

                        if (!NSK_JVMTI_VERIFY (jvmti->ClearFieldAccessWatch(watchFieldClass, fieldId))) {

                            NSK_DISPLAY0(" Agent :: failed to drop field watces.\n");

                            nsk_jvmti_agentFailed();

                        } else {

                            NSK_DISPLAY0(" Agent :: Sucessfully droped watches.\n");

                            retvalue = JNI_TRUE;

                        }

                    }

                }

            }

        } else {

            NSK_DISPLAY0(" Agent :: Thread should be suspended to its pop frame.\n");

        }

    }

    return retvalue;

}

}