/*
 * 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 "jni_tools.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 = NULL;
static jvmtiLocalVariableEntry *table = NULL;
static jint entryCount = 0;
static jint methodExitCnt = -1;

void print_LocalVariableEntry(jvmtiLocalVariableEntry *lvt_elem) {
  printf("\n Var name: %s, slot: %d", lvt_elem->name, lvt_elem->slot);
  printf(", start_bci: %" LL "d", lvt_elem->start_location);
  printf(", end_bci: %" LL "d",   lvt_elem->start_location + lvt_elem->length);
  printf(", signature: %s\n", lvt_elem->signature);
}

void JNICALL MethodExit(jvmtiEnv *jvmti_env, JNIEnv *env,
        jthread thr, jmethodID method,
        jboolean was_poped_by_exception, jvalue return_value) {
    jvmtiError err;
    jint i;
    jmethodID frame_method;
    jlocation location;
    jint intVal;
    jfloat floatVal;
    jdouble doubleVal;
    jobject obj;

    if (mid == method) {

        err = jvmti_env->GetFrameLocation(thr, 0,
                                             &frame_method, &location);
        if (err != JVMTI_ERROR_NONE) {
            printf("\t failure: %s (%d)\n", TranslateError(err), err);
            result = STATUS_FAILED;
            return;
        }
        if (frame_method != method) {
            printf("\t failure: GetFrameLocation returned wrong jmethodID\n");
            result = STATUS_FAILED;
            return;
        }

        printf("\n MethodExit: BEGIN %d, Current frame bci: %" LL "d\n\n",
                ++methodExitCnt, location);
        for (i = 0; i < entryCount; i++) {
            if (table[i].start_location > location ||
                table[i].start_location + table[i].length < location) {
                continue;  /* The local variable is not visible */
            }
            print_LocalVariableEntry(&table[i]);

            err = jvmti->GetLocalInt(thr, 0, table[i].slot, &intVal);
            printf(" GetLocalInt:     %s (%d)\n", TranslateError(err), err);
            if (err != JVMTI_ERROR_NONE && table[i].signature[0] == 'I') {
                result = STATUS_FAILED;
            }

            err = jvmti->GetLocalFloat(thr, 0, table[i].slot, &floatVal);
            printf(" GetLocalFloat:   %s (%d)\n", TranslateError(err), err);
            if (err != JVMTI_ERROR_NONE && table[i].signature[0] == 'F') {
                result = STATUS_FAILED;
            }

            err = jvmti->GetLocalDouble(thr, 0, table[i].slot, &doubleVal);
            printf(" GetLocalDouble:  %s (%d)\n", TranslateError(err), err);
            if (err != JVMTI_ERROR_NONE && table[i].signature[0] == 'D') {
                result = STATUS_FAILED;
            }

            err = jvmti->GetLocalObject(thr, 0, table[i].slot, &obj);
            printf(" GetLocalObject:  %s (%d)\n", TranslateError(err), err);
            if (err != JVMTI_ERROR_NONE && table[i].signature[0] == 'L') {
                result = STATUS_FAILED;
            }
        }
        printf("\n MethodExit: END %d\n\n", methodExitCnt);
        fflush(stdout);
    }
}

#ifdef STATIC_BUILD
JNIEXPORT jint JNICALL Agent_OnLoad_getlocal003(JavaVM *jvm, char *options, void *reserved) {
    return Agent_Initialize(jvm, options, reserved);
}
JNIEXPORT jint JNICALL Agent_OnAttach_getlocal003(JavaVM *jvm, char *options, void *reserved) {
    return Agent_Initialize(jvm, options, reserved);
}
JNIEXPORT jint JNI_OnLoad_getlocal003(JavaVM *jvm, char *options, void *reserved) {
    return JNI_VERSION_1_8;
}
#endif
jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved) {
    jint res;
    jvmtiError err;

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

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

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

    if (!caps.can_access_local_variables) {
        printf("Warning: Access to local variables is not implemented\n");
    } else if (caps.can_generate_method_exit_events) {
        callbacks.MethodExit = &MethodExit;
        err = jvmti->SetEventCallbacks(&callbacks, sizeof(callbacks));
        if (err != JVMTI_ERROR_NONE) {
            printf("(SetEventCallbacks) unexpected error: %s (%d)\n",
                   TranslateError(err), err);
            return JNI_ERR;
        }
    } else {
        printf("Warning: MethodExit event is not implemented\n");
    }

    return JNI_OK;
}

JNIEXPORT void JNICALL
Java_nsk_jvmti_unit_GetLocalVariable_getlocal003_getMeth(JNIEnv *env, jclass cls) {
    jvmtiError err;

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

    if (!caps.can_access_local_variables ||
        !caps.can_generate_method_exit_events) return;

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

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

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

JNIEXPORT void JNICALL
Java_nsk_jvmti_unit_GetLocalVariable_getlocal003_checkLoc(JNIEnv *env,
        jclass cls, jthread thr) {
    jvmtiError err;
    jvmtiLocalVariableEntry *table;
    jint entryCount;
    jmethodID mid;
    jint locVar;
    jint i, j;
    int  overlap = 0;

    if (jvmti == NULL) {
        return;
    }

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

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

    for (i = 0; i < entryCount; i++) {
        print_LocalVariableEntry(&table[i]);

        err = jvmti->GetLocalInt(thr, 1, table[i].slot, &locVar);

        printf(" GetLocalInt: %s (%d)\n", TranslateError(err), err);
        if (strcmp(table[i].name, "intArg") == 0) {
            if (err != JVMTI_ERROR_NONE) {
               printf(" failure: JVMTI_ERROR_NONE is expected\n");
               result = STATUS_FAILED;
            }
        }
        else if (strcmp(table[i].name, "pi") == 0) {
            if (err != JVMTI_ERROR_TYPE_MISMATCH) {
               printf(" failure: JVMTI_ERROR_TYPE_MISMATCH is expected\n");
               result = STATUS_FAILED;
            }
        } else {
            if (err != JVMTI_ERROR_INVALID_SLOT) {
                printf(" failure: JVMTI_ERROR_INVALID_SLOT is expected\n");
                result = STATUS_FAILED;
            }
        }
        if (table[i].slot != 2) {
           continue;
        }

        for (j = 0; j < entryCount; j++) {
           /* We do cross checks between all variables having slot #2.
            * No overlapping between location ranges are allowed.
            */
           if (table[j].slot != 2 || i == j) {
              continue;
           }
           if (table[i].start_location > table[j].start_location + table[j].length ||
               table[j].start_location > table[i].start_location + table[i].length
           ) {
               continue; /* Everything is Ok */
           }

           printf(" failure: locations of vars with slot #2 are overlaped:\n");
           print_LocalVariableEntry(&table[i]);
           print_LocalVariableEntry(&table[j]);
           overlap++;
           result = STATUS_FAILED;
        }
    }
    if (!overlap) {
        printf("\n Succes: locations of vars with slot #2 are NOT overlaped\n\n");
    }
    fflush(stdout);
}

JNIEXPORT jint JNICALL
Java_nsk_jvmti_unit_GetLocalVariable_getlocal003_getRes(JNIEnv *env, jclass cls) {
    return result;
}

#ifdef __cplusplus
}
#endif