/*
 * 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 jvmtiEventCallbacks callbacks;
static jint result = PASSED;
static jboolean printdump = JNI_FALSE;
static jmethodID mid;

void JNICALL Breakpoint(jvmtiEnv *jvmti_env, JNIEnv *env,
        jthread thread, jmethodID method, jlocation location) {
    jvmtiError err;

    if (method != mid) {
        printf("bp: don't know where we get called from");
        result = STATUS_FAILED;
        return;
    }
    if (printdump == JNI_TRUE) {
        printf(">>> breakpoint in C\n");
    }
    err = (*jvmti_env)->ClearBreakpoint(jvmti_env, mid, 0);
    if (err != JVMTI_ERROR_NONE) {
        printf("(ClearBreakpoint) unexpected error: %s (%d)\n",
               TranslateError(err), err);
        result = STATUS_FAILED;
        return;
    }

    if (printdump == JNI_TRUE) {
        printf(">>> about to pop to a native frame\n");
    }
    err = (*jvmti_env)->PopFrame(jvmti_env, thread);
    if (err != JVMTI_ERROR_OPAQUE_FRAME) {
        printf("(PopFrame) error expected: JVMTI_ERROR_OPAQUE_FRAME,\n");
        printf("\t actual: %s (%d)\n", TranslateError(err), err);
        result = STATUS_FAILED;
    }
}

#ifdef STATIC_BUILD
JNIEXPORT jint JNICALL Agent_OnLoad_popframe007(JavaVM *jvm, char *options, void *reserved) {
    return Agent_Initialize(jvm, options, reserved);
}
JNIEXPORT jint JNICALL Agent_OnAttach_popframe007(JavaVM *jvm, char *options, void *reserved) {
    return Agent_Initialize(jvm, options, reserved);
}
JNIEXPORT jint JNI_OnLoad_popframe007(JavaVM *jvm, char *options, void *reserved) {
    return JNI_VERSION_1_8;
}
#endif
jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved) {
    jvmtiError err;
    jint res;

    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;
    }

    err = (*jvmti)->GetPotentialCapabilities(jvmti, &caps);
    if (err != JVMTI_ERROR_NONE) {
        printf("(GetPotentialCapabilities) unexpected error: %s (%d)\n",
               TranslateError(err), err);
        return JNI_ERR;
    }

    err = (*jvmti)->AddCapabilities(jvmti, &caps);
    if (err != JVMTI_ERROR_NONE) {
        printf("(AddCapabilities) unexpected error: %s (%d)\n",
               TranslateError(err), err);
        return JNI_ERR;
    }

    err = (*jvmti)->GetCapabilities(jvmti, &caps);
    if (err != JVMTI_ERROR_NONE) {
        printf("(GetCapabilities) unexpected error: %s (%d)\n",
               TranslateError(err), err);
        return JNI_ERR;
    }

    if (!caps.can_pop_frame) {
        printf("Warning: PopFrame is not implemented\n");
    }

    if (caps.can_generate_breakpoint_events) {
        callbacks.Breakpoint = &Breakpoint;
        err = (*jvmti)->SetEventCallbacks(jvmti, &callbacks, sizeof(callbacks));
        if (err != JVMTI_ERROR_NONE) {
            printf("(SetEventCallbacks) unexpected error: %s (%d)\n",
                   TranslateError(err), err);
            return JNI_ERR;
        }
    } else {
        printf("Warning: Breakpoint event is not implemented\n");
    }

    return JNI_OK;
}

JNIEXPORT void JNICALL
Java_nsk_jvmti_PopFrame_popframe007_getReady(JNIEnv *env,
        jclass cls, jthread thr) {
    jvmtiError err;
    jclass clazz;

    if (jvmti == NULL) {
        printf("JVMTI client was not properly loaded!\n");
        result = STATUS_FAILED;
        return;
    }

    if (!caps.can_pop_frame || !caps.can_generate_breakpoint_events) {
        return;
    }

    clazz = JNI_ENV_PTR(env)->GetObjectClass(JNI_ENV_ARG(env, thr));
    if (clazz == NULL) {
        printf("Cannot get class of the thread object\n");
        result = STATUS_FAILED;
        return;
    }

    mid = JNI_ENV_PTR(env)->GetStaticMethodID(JNI_ENV_ARG(env, clazz),
        "C", "()V");
    if (mid == NULL) {
        printf("Cannot find Method ID for method \"C\"\n");
        result = STATUS_FAILED;
        return;
    }

    err = (*jvmti)->SetBreakpoint(jvmti, mid, 0);
    if (err != JVMTI_ERROR_NONE) {
        printf("(SetBreakpoint) unexpected error: %s (%d)\n",
               TranslateError(err), err);
        result = STATUS_FAILED;
        return;
    }

    err = (*jvmti)->SetEventNotificationMode(jvmti, JVMTI_ENABLE,
        JVMTI_EVENT_BREAKPOINT, NULL);
    if (err != JVMTI_ERROR_NONE) {
        printf("Failed to enable BREAKPOINT event: %s (%d)\n",
               TranslateError(err), err);
        result = STATUS_FAILED;
    }
}

JNIEXPORT jint JNICALL
Java_nsk_jvmti_PopFrame_popframe007_getRes(JNIEnv *env, jclass cls) {
    return result;
}

JNIEXPORT void JNICALL
Java_nsk_jvmti_PopFrame_popframe007_B(JNIEnv *env, jclass cls) {
    if (mid != NULL) {
        JNI_ENV_PTR(env)->CallStaticVoidMethod(JNI_ENV_ARG(env, cls), mid);
    }
}

#ifdef __cplusplus
}
#endif