/*
 * Copyright (c) 2003, 2024, 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 <jvmti.h>
#include "jvmti_common.hpp"

extern "C" {

#define STATUS_FAILED 2
#define PASSED 0

/* tested method */
static const char *METHODS[] = {
    "nativeMethod", "()V"
};

/* event counter for the tested method and expected number
   of the events */
static volatile int bindEv[] = {
    0, 1
};

static const char *CLASS_SIG =
    "Lnativemethbind03$TestedClass;";

static volatile jint result = PASSED;
static jvmtiEnv *jvmti = nullptr;
static jvmtiEventCallbacks callbacks;
static jrawMonitorID counter_lock;

/** callback functions **/
void JNICALL
NativeMethodBind(jvmtiEnv *jvmti, JNIEnv *jni, jthread thread, jmethodID method, void *addr, void **new_addr) {
  jvmtiPhase phase;
  jvmtiError err;
  char *methNam, *methSig;

  RawMonitorLocker rml(jvmti, jni, counter_lock);

  LOG(">>>> NativeMethodBind event received\n");

  err = jvmti->GetPhase(&phase);
  if (err != JVMTI_ERROR_NONE) {
    LOG(">>>> Error getting phase\n");
    result = STATUS_FAILED;
    return;
  }

  if (phase != JVMTI_PHASE_LIVE && phase != JVMTI_PHASE_START) {
    return;
  }

  err = jvmti->GetMethodName(method, &methNam, &methSig, nullptr);
  if (err != JVMTI_ERROR_NONE) {
    result = STATUS_FAILED;
    COMPLAIN("TEST FAILED: unable to get method name during NativeMethodBind callback\n\n");
    return;
  }

  if ((strcmp(methNam, METHODS[0]) == 0) && (strcmp(methSig, METHODS[1]) == 0)) {
    bindEv[0]++;
    LOG("\tmethod: \"%s %s\"\n", methNam, methSig);
  }

  if (methNam != nullptr) {
    err = jvmti->Deallocate((unsigned char *) methNam);
    if (err != JVMTI_ERROR_NONE) {
      result = STATUS_FAILED;
      LOG("TEST FAILED: unable to deallocate memory pointed to method name\n\n");
    }
  }

  if (methSig != nullptr) {
    err = jvmti->Deallocate((unsigned char *) methSig);
    if (err != JVMTI_ERROR_NONE) {
      result = STATUS_FAILED;
      LOG("TEST FAILED: unable to deallocate memory pointed to method signature\n\n");
    }
  }

  LOG("<<<<\n\n");
}

void JNICALL
VMDeath(jvmtiEnv *jvmti, JNIEnv *jni) {
  LOG("VMDeath event received\n");

  if (bindEv[0] != bindEv[1]) {
    result = STATUS_FAILED;
    LOG("TEST FAILED: wrong NativeMethodBind events\n"
        "\tfor tested method \"%s %s\" bound with \"%s\":\n"
        "\tgot: %d\texpected: %d\n\n",
        METHODS[0], METHODS[1], CLASS_SIG, bindEv[0], bindEv[1]);
  } else {
    LOG("CHECK PASSED: %d NativeMethodBind event(s)\n"
        "\tfor tested method \"%s %s\" bound with \"%s\"\n"
        "\tas expected\n",
        bindEv[0], METHODS[0], METHODS[1], CLASS_SIG);
  }

  if (result == STATUS_FAILED)
    exit(95 + STATUS_FAILED);
}

/* dummy method used only to provoke NativeMethodBind event */
static void JNICALL
nativeMethod(JNIEnv *jni, jobject obj) {
  LOG("inside the nativeMethod()\n");
}

/* dummy method used only to provoke NativeMethodBind event */
JNIEXPORT void JNICALL
Java_nativemethbind03_registerNative(JNIEnv *jni, jobject obj) {
  jclass testedCls = nullptr;
  JNINativeMethod meth;

  LOG("Inside the registerNative()\n"
      "Finding class \"%s\" ...\n", CLASS_SIG);
  testedCls = jni->FindClass(CLASS_SIG);
  if (testedCls == nullptr) {
    result = STATUS_FAILED;
    COMPLAIN("TEST FAILURE: unable to find class \"%s\"\n\n", CLASS_SIG);
    return;
  }

  meth.name = (char *) METHODS[0];
  meth.signature = (char *) METHODS[1];
  meth.fnPtr = (void *) nativeMethod;

  LOG("Calling RegisterNatives() with \"%s %s\"\n"
      "\tfor class \"%s\" ...\n", METHODS[0], METHODS[1], CLASS_SIG);
  if (jni->RegisterNatives(testedCls, &meth, 1) != 0) {
    result = STATUS_FAILED;
    COMPLAIN("TEST FAILURE: unable to RegisterNatives() \"%s %s\" for class \"%s\"\n\n",
             METHODS[0], METHODS[1], CLASS_SIG);
  }

  LOG("Calling UnregisterNatives() for class \"%s\" ...\n", CLASS_SIG);
  if (jni->UnregisterNatives(testedCls) != 0) {
    result = STATUS_FAILED;
    COMPLAIN("TEST FAILURE: unable to UnregisterNatives() \"%c %c\" for class \"%s\"\n\n",
             METHODS[1][0], METHODS[1][1], CLASS_SIG);
  }
}

jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved) {
  jvmtiCapabilities caps;
  jvmtiError err;
  jint res;

  res = jvm->GetEnv((void **) &jvmti, JVMTI_VERSION_9);
  if (res != JNI_OK || jvmti == nullptr) {
    LOG("Wrong result of a valid call to GetEnv!\n");
    return JNI_ERR;
  }


  /* create a raw monitor */
  counter_lock = create_raw_monitor(jvmti, "_counter_lock");

  /* add capability to generate compiled method events */
  memset(&caps, 0, sizeof(jvmtiCapabilities));
  caps.can_generate_native_method_bind_events = 1;

  err = jvmti->AddCapabilities(&caps);
  if (err != JVMTI_ERROR_NONE) {
    return JNI_ERR;
  }

  err = jvmti->GetCapabilities(&caps);
  if (err != JVMTI_ERROR_NONE) {
    return JNI_ERR;
  }

  if (!caps.can_generate_native_method_bind_events)
    LOG("Warning: generation of native method bind events is not implemented\n");

  /* set event callback */
  LOG("setting event callbacks ...\n");
  (void) memset(&callbacks, 0, sizeof(callbacks));
  callbacks.NativeMethodBind = &NativeMethodBind;
  callbacks.VMDeath = &VMDeath;
  err = jvmti->SetEventCallbacks(&callbacks, sizeof(callbacks));
  if (err != JVMTI_ERROR_NONE)
    return JNI_ERR;

  LOG("setting event callbacks done\nenabling JVMTI events ...\n");
  err = jvmti->SetEventNotificationMode(JVMTI_ENABLE, JVMTI_EVENT_NATIVE_METHOD_BIND, nullptr);
  if (err != JVMTI_ERROR_NONE) {
    return JNI_ERR;
  }
  err = jvmti->SetEventNotificationMode(JVMTI_ENABLE, JVMTI_EVENT_VM_DEATH, nullptr);
  if (err != JVMTI_ERROR_NONE) {
    return JNI_ERR;
  }
  LOG("enabling the events done\n\n");

  return JNI_OK;
}

JNIEXPORT jint JNICALL Agent_OnLoad(JavaVM *jvm, char *options, void *reserved) {
  return Agent_Initialize(jvm, options, reserved);
}

JNIEXPORT jint JNICALL Agent_OnAttach(JavaVM *jvm, char *options, void *reserved) {
  return Agent_Initialize(jvm, options, reserved);
}

}