/*
 * Copyright (c) 2007, 2019, 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 <jvmti.h>
#include "agent_common.h"
#include <jni.h>
#include <string.h>
#include "jvmti_tools.h"
#include "JVMTITools.h"

/*
   T002:
   1. Set a breakpoint in method b().
   2. Call method a() which calls b().
   Upon reaching the breakpoint, enable SingleStep.
   3. Redefine class within SingleStep callback. New class version
   contains the same method b() and the changed method a(). Stepping
   should be continued in the method b().
   4. Pop a currently executed frame. Stepping should be continued
   on invoke instruction of the obsolete method a().
   5. Pop a frame once more. Stepping should be continued
   on invoke instruction of main method and then in the changed
   method b().
*/

extern "C" {

#define FILE_NAME "nsk/jvmti/scenarios/hotswap/HS203/hs203t002/MyThread"
#define SEARCH_NAME "nsk/jvmti/scenarios/hotswap/HS203/hs203t002/MyThread"
#define METHOD_NAME "doTask2"
#define METHOD_SIGN "()V"
#define CLASS_NAME "Lnsk/jvmti/scenarios/hotswap/HS203/hs203t002/MyThread;"
static jint redefineNumber;
static jvmtiEnv * jvmti;

JNIEXPORT void JNICALL
callbackClassLoad(jvmtiEnv *jvmti,
                                        JNIEnv* jni,
                                        jthread thread,
                                        jclass klass) {
    char * className;
    char * generic;
    redefineNumber=0;
    jvmti->GetClassSignature(klass, &className, &generic);
    if (strcmp(className,CLASS_NAME) == 0) {
        jmethodID method;
        method = jni->GetMethodID(klass,METHOD_NAME,METHOD_SIGN);
        if (method != NULL) {
            jlocation start;
            jlocation end;
            jvmtiError err ;
            err=jvmti->GetMethodLocation(method, &start, &end);
            if (err == JVMTI_ERROR_NONE) {
                nsk_printf("Agent:: NO ERRORS FOUND \n");
                err= jvmti->SetBreakpoint(method, start);
                if (err == JVMTI_ERROR_NONE) {
                    nsk_printf("Agent:: Breakpoint set \n");
                } else {
                    nsk_printf("Agent:: ***ERROR OCCURED ... in SET BREAK POINT ERROR \n");
                }
            } else {
                nsk_printf("Agent:: ***ERROR OCCURED .. in METHOD LOCATION FINDER \n");
            }
        } else {
            nsk_printf("Agent:: ***ERROR OCCURED .. COUND NOT FIND THE METHOD AND SIGNATURE SPECIFIED \n");
        }
    }
}

void JNICALL callbackSingleStep(jvmtiEnv *jvmti,
        JNIEnv* jni, jthread thread,
        jmethodID method, jlocation location) {
    jclass threadClass;
    jvmtiError err;
    char fileName[512];

    threadClass = jni->FindClass(SEARCH_NAME);
    nsk_printf(" %d..",redefineNumber);
    nsk_jvmti_getFileName(redefineNumber, FILE_NAME, fileName, sizeof(fileName)/sizeof(char));

    if (nsk_jvmti_redefineClass(jvmti, threadClass,fileName)) {
        nsk_printf("Agent:: Redefined..\n");
    } else {
        nsk_printf(" Failed to redefine..\n");
        return;
    }
    err=jvmti->SuspendThread(thread);
    if (err == JVMTI_ERROR_NONE) {
        nsk_printf("Agent:: Succeded in suspending..\n");
    } else {
        nsk_printf(" ## Error occured %s \n",TranslateError(err));
    }
}

void JNICALL callbackBreakpoint(jvmtiEnv *jvmti,
                                                                JNIEnv* jni,
                                                                jthread thread,
                                                                jmethodID method,
                                                                jlocation location) {
    nsk_printf("Agent::... BreakPoint Reached..\n");
    if (nsk_jvmti_enableNotification(jvmti,JVMTI_EVENT_SINGLE_STEP,thread) == JNI_OK) {
        nsk_printf(" ....   Enabled..\n");
    }
    return;
}


#ifdef STATIC_BUILD
JNIEXPORT jint JNICALL Agent_OnLoad_hs203t002(JavaVM *jvm, char *options, void *reserved) {
    return Agent_Initialize(jvm, options, reserved);
}
JNIEXPORT jint JNICALL Agent_OnAttach_hs203t002(JavaVM *jvm, char *options, void *reserved) {
    return Agent_Initialize(jvm, options, reserved);
}
JNIEXPORT jint JNI_OnLoad_hs203t002(JavaVM *jvm, char *options, void *reserved) {
    return JNI_VERSION_1_8;
}
#endif
jint Agent_Initialize(JavaVM *vm, char *options, void *reserved) {
        jint rc ;
    nsk_printf("Agent:: VM.. Started..\n");
    rc=vm->GetEnv((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_printf("# error agent Failed to parse options \n");
            return JNI_ERR;
        }
        memset(&caps, 0, sizeof(caps));
        caps.can_redefine_classes = 1;
        caps.can_suspend=1;
        caps.can_pop_frame=1;
        caps.can_generate_breakpoint_events=1;
        caps.can_generate_all_class_hook_events=1;
        caps.can_generate_single_step_events=1;
        jvmti->AddCapabilities(&caps);

        memset(&eventCallbacks, 0, sizeof(eventCallbacks));
        eventCallbacks.ClassLoad =callbackClassLoad;
        eventCallbacks.Breakpoint = callbackBreakpoint;
        eventCallbacks.SingleStep =callbackSingleStep;
        rc=jvmti->SetEventCallbacks(&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_LOAD, NULL) &&
                nsk_jvmti_enableNotification(jvmti,JVMTI_EVENT_BREAKPOINT, NULL)) {
            nsk_printf("Agent :: NOTIFICATIONS ARE ENABLED \n");
        } else {
            nsk_printf(" Error in Eanableing Notifications..");
        }
    }
    return JNI_OK;
}


JNIEXPORT jboolean JNICALL
Java_nsk_jvmti_scenarios_hotswap_HS203_hs203t002_hs203t002_popThreadFrame(JNIEnv * jni,
        jclass clas,
        jthread thread) {
    jvmtiError err ;
    jboolean retvalue;
    jint state;
    nsk_printf("Agent:: POPING THE FRAME....\n");
    retvalue = JNI_FALSE;
    jvmti->GetThreadState(thread, &state);
    if (state & JVMTI_THREAD_STATE_SUSPENDED) {
        err = jvmti->PopFrame(thread);
        if (err == JVMTI_ERROR_NONE) {
            nsk_printf("Agent:: NO Errors poped very well ..\n");
            retvalue = JNI_TRUE;
        } else {
            nsk_printf(" ## Error occured %s \n",TranslateError(err));
        }
    } else {
        nsk_printf("Agent:: Thread was not suspened.. check for capabilities, and java method signature \n");
    }
    return retvalue;
}

JNIEXPORT jboolean JNICALL
Java_nsk_jvmti_scenarios_hotswap_HS203_hs203t002_hs203t002_resumeThread(JNIEnv * jni,
        jclass clas,
        jthread thread) {
    jvmtiError err ;
    jboolean retvalue;
    retvalue = JNI_FALSE;
    err =jvmti->SetEventNotificationMode(JVMTI_DISABLE,JVMTI_EVENT_SINGLE_STEP,thread);
    if (err == JVMTI_ERROR_NONE) {
        nsk_printf(" Agent:: cleared Single Step event");
    } else {
        nsk_printf(" Agent :: Failed to clear Single Step Event");
    }
    err =jvmti->SetEventNotificationMode(JVMTI_DISABLE,JVMTI_EVENT_BREAKPOINT,thread);
    if (err == JVMTI_ERROR_NONE) {
        nsk_printf(" Agent:: cleared Break point event");
    } else {
        nsk_printf(" Agent :: Failed to clear Single Step Event");
    }
    err = jvmti->ResumeThread(thread);
    if (err == JVMTI_ERROR_NONE) {
        nsk_printf(" Agent:: Thread Resumed..");
    } else {
        nsk_printf(" Failed.. to Resume the thread.");
    }
    return retvalue;
}

JNIEXPORT jboolean JNICALL
Java_nsk_jvmti_scenarios_hotswap_HS203_hs203t002_hs203t002_suspendThread(JNIEnv * jni,
        jclass clas,
        jthread thread) {
    jvmtiError err ;
    jboolean retvalue;
    retvalue = JNI_FALSE;
    err = jvmti->SuspendThread(thread);
    if (err == JVMTI_ERROR_NONE) {
        nsk_printf(" Agent:: Thread suspended..");
        retvalue= JNI_TRUE;
    } else {
        nsk_printf(" ## Error occured %s \n",TranslateError(err));
    }
    return retvalue;
}

}