/*

 * 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 <string.h>

#include "jvmti.h"

#include "agent_common.h"

#include "jni_tools.h"

#include "jvmti_tools.h"

extern "C" {

/* ============================================================================= */

/* scaffold objects */

static jlong timeout = 0;

/* constant names */

#define DEBUGEE_CLASS_NAME    "nsk/jvmti/ClassFileLoadHook/classfloadhk002"

#define TESTED_CLASS_NAME     "nsk/jvmti/ClassFileLoadHook/classfloadhk002r"

#define TESTED_CLASS_SIG      "L" TESTED_CLASS_NAME ";"

#define BYTECODE_FIELD_SIG    "[B"

#define ORIG_BYTECODE_FIELD_NAME  "origClassBytes"

static unsigned char* origClassBytes = NULL;

static jint origClassSize = 0;

static volatile int eventsCount = 0;

/* ============================================================================= */

/** Check (strictly or not) if bytecode has expected size and bytes or complain an error. */

static int checkBytecode(const char kind[], jint size, const unsigned char bytes[],

                            jint expectedSize, const unsigned char expectedBytes[],

                            int strict) {

    int success = NSK_TRUE;

    NSK_DISPLAY3("Check %s bytecode: 0x%p:%d\n", kind, (void*)bytes, (int)size);

    if (nsk_getVerboseMode()) {

        nsk_printHexBytes("   ", 16, size, bytes);

    }

    if (bytes == NULL) {

        NSK_COMPLAIN2("Unexpected NULL pointer to %s bytecode in CLASS_FILE_LOAD_HOOK: 0x%p\n",

                                                            kind, (void*)bytes);

        return NSK_FALSE;

    }

    if (size <= 0) {

        NSK_COMPLAIN2("Unexpected zero size of %s bytecode in CLASS_FILE_LOAD_HOOK: %d\n",

                                                            kind, (int)size);

        return NSK_FALSE;

    }

    if (strict) {

        if (size != expectedSize) {

            NSK_COMPLAIN3("Unexpected size of %s bytecode in CLASS_FILE_LOAD_HOOK:\n"

                          "#   got size: %d\n"

                          "#   expected: %d\n",

                            kind, (int)size, (int)expectedSize);

            success = NSK_FALSE;

        } else {

            jint different = 0;

            jint i;

            for (i = 0; i < size; i++) {

                if (bytes[i] != expectedBytes[i]) {

                    different++;

                }

            }

            if (different > 0) {

                NSK_COMPLAIN2("Unexpected bytes in %s bytecode in CLASS_FILE_LOAD_HOOK:\n"

                              "#   different bytes: %d\n"

                              "#   total bytes:     %d\n",

                                (int)different, (int)size);

                success = NSK_FALSE;

            }

        }

        if (!success) {

            NSK_COMPLAIN2("Got %s bytecode is not equal to expected bytecode: %d bytes\n",

                                                                        kind, expectedSize);

            if (nsk_getVerboseMode()) {

                nsk_printHexBytes("   ", 16, expectedSize, expectedBytes);

            }

        } else {

            NSK_DISPLAY1("All %s bytecode is equal to expected one\n", kind);

        }

    }

    return success;

}

/** Get classfile bytecode from a static field of given class. */

static int getBytecode(jvmtiEnv* jvmti, JNIEnv* jni, jclass cls,

                                    const char fieldName[], const char fieldSig[],

                                    jint* size, unsigned char* *bytes) {

    jfieldID fieldID = NULL;

    jbyteArray array = NULL;

    jbyte* elements;

    int i;

    NSK_DISPLAY1("Find static field: %s\n", fieldName);

    if (!NSK_JNI_VERIFY(jni, (fieldID =

            NSK_CPP_STUB4(GetStaticFieldID, jni, cls, fieldName, fieldSig)) != NULL)) {

        nsk_jvmti_setFailStatus();

        return NSK_FALSE;

    }

    NSK_DISPLAY1("  ... got fieldID: 0x%p\n", (void*)fieldID);

    NSK_DISPLAY1("Get classfile bytes array from static field: %s\n", fieldName);

    if (!NSK_JNI_VERIFY(jni, (array = (jbyteArray)

            NSK_CPP_STUB3(GetStaticObjectField, jni, cls, fieldID)) != NULL)) {

        nsk_jvmti_setFailStatus();

        return NSK_FALSE;

    }

    NSK_DISPLAY1("  ... got array object: 0x%p\n", (void*)array);

    if (!NSK_JNI_VERIFY(jni, (*size =

            NSK_CPP_STUB2(GetArrayLength, jni, array)) > 0)) {

        nsk_jvmti_setFailStatus();

        return NSK_FALSE;

    }

    NSK_DISPLAY1("  ... got array size: %d bytes\n", (int)*size);

    {

        jboolean isCopy;

        if (!NSK_JNI_VERIFY(jni, (elements =

                NSK_CPP_STUB3(GetByteArrayElements, jni, array,

                                                            &isCopy)) != NULL)) {

            nsk_jvmti_setFailStatus();

        return NSK_FALSE;

        }

    }

    NSK_DISPLAY1("  ... got elements list: 0x%p\n", (void*)elements);

    if (!NSK_JVMTI_VERIFY(

            NSK_CPP_STUB3(Allocate, jvmti, *size, bytes))) {

        nsk_jvmti_setFailStatus();

        return NSK_FALSE;

    }

    NSK_DISPLAY1("  ... created bytes array: 0x%p\n", (void*)*bytes);

    for (i = 0; i < *size; i++) {

        (*bytes)[i] = (unsigned char)elements[i];

    }

    NSK_DISPLAY1("  ... copied bytecode: %d bytes\n", (int)*size);

    NSK_DISPLAY1("Release elements list: 0x%p\n", (void*)elements);

    NSK_TRACE(NSK_CPP_STUB4(ReleaseByteArrayElements, jni, array, elements, JNI_ABORT));

    NSK_DISPLAY0("  ... released\n");

    return NSK_TRUE;

}

/* ============================================================================= */

/** Agent algorithm. */

static void JNICALL

agentProc(jvmtiEnv* jvmti, JNIEnv* jni, void* arg) {

    NSK_DISPLAY0("Wait for debuggee to become ready\n");

    if (!NSK_VERIFY(nsk_jvmti_waitForSync(timeout)))

        return;

    /* perform testing */

    {

        NSK_DISPLAY0(">>> Obtain original bytecode of tested class\n");

        {

            jclass debugeeClass = NULL;

            NSK_DISPLAY1("Find debugee class: %s\n", DEBUGEE_CLASS_NAME);

            if (!NSK_JNI_VERIFY(jni, (debugeeClass =

                    NSK_CPP_STUB2(FindClass, jni, DEBUGEE_CLASS_NAME)) != NULL)) {

                nsk_jvmti_setFailStatus();

                return;

            }

            NSK_DISPLAY1("  ... found class: 0x%p\n", (void*)debugeeClass);

            if (!NSK_VERIFY(getBytecode(jvmti, jni, debugeeClass,

                                        ORIG_BYTECODE_FIELD_NAME,

                                        BYTECODE_FIELD_SIG,

                                        &origClassSize, &origClassBytes)))

                return;

        }

        NSK_DISPLAY0(">>> Testcase #1: Load tested class and check CLASS_FILE_LOAD_HOOK event\n");

        {

            jvmtiEvent event = JVMTI_EVENT_CLASS_FILE_LOAD_HOOK;

            NSK_DISPLAY1("Enable event: %s\n", "CLASS_FILE_LOAD_HOOK");

            if (!NSK_VERIFY(nsk_jvmti_enableEvents(JVMTI_ENABLE, 1, &event, NULL)))

                return;

            NSK_DISPLAY0("  ... event enabled\n");

            NSK_DISPLAY0("Let debugee to load tested class\n");

            if (!NSK_VERIFY(nsk_jvmti_resumeSync()))

                return;

            NSK_DISPLAY0("Wait for tested class to be loaded\n");

            if (!NSK_VERIFY(nsk_jvmti_waitForSync(timeout)))

                return;

            NSK_DISPLAY1("Disable event: %s\n", "CLASS_FILE_LOAD_HOOK");

            if (NSK_VERIFY(nsk_jvmti_enableEvents(JVMTI_DISABLE, 1, &event, NULL))) {

                NSK_DISPLAY0("  ... event disabled\n");

            }

            NSK_DISPLAY1("Check if event was received: %s\n", "CLASS_FILE_LOAD_HOOK");

            if (eventsCount != 1) {

                NSK_COMPLAIN3("Unexpected number of %s events for tested class:\n"

                              "#   got events: %d\n"

                              "#   expected:   %d\n",

                                "CLASS_FILE_LOAD_HOOK",

                                eventsCount, 1);

                nsk_jvmti_setFailStatus();

            } else {

                NSK_DISPLAY1("  ... received: %d events\n", eventsCount);

            }

        }

        NSK_DISPLAY0(">>> Clean used data\n");

        {

            NSK_DISPLAY1("Deallocate bytecode array: 0x%p\n", (void*)origClassBytes);

            if (!NSK_JVMTI_VERIFY(

                        NSK_CPP_STUB2(Deallocate, jvmti, origClassBytes))) {

                nsk_jvmti_setFailStatus();

            }

        }

    }

    NSK_DISPLAY0("Let debugee to finish\n");

    if (!NSK_VERIFY(nsk_jvmti_resumeSync()))

        return;

}

/* ============================================================================= */

/** Callback for CLASS_FILE_LOAD_HOOK event **/

static void JNICALL

callbackClassFileLoadHook(jvmtiEnv *jvmti_env, JNIEnv *env,

                            jclass class_being_redefined,

                            jobject loader, const char* name, jobject protection_domain,

                            jint class_data_len, const unsigned char* class_data,

                            jint *new_class_data_len, unsigned char** new_class_data) {

    NSK_DISPLAY5("  <CLASS_FILE_LOAD_HOOK>: name: %s, loader: 0x%p, redefined: 0x%p, bytecode: 0x%p:%d\n",

                        nsk_null_string(name), (void*)loader, (void*)class_being_redefined,

                        (void*)class_data, (int)class_data_len);

    if (name != NULL && (strcmp(name, TESTED_CLASS_NAME) == 0)) {

        NSK_DISPLAY1("SUCCESS! CLASS_FILE_LOAD_HOOK for tested class: %s\n", TESTED_CLASS_NAME);

        eventsCount++;

        NSK_DISPLAY1("Check class_being_redefined: 0x%p\n", (void*)class_being_redefined);

        if (class_being_redefined != NULL) {

            NSK_COMPLAIN1("Unexpected not NULL class_being_redefined in CLASS_FILE_LOAD_HOOK: 0x%p\n",

                                                    (void*)class_being_redefined);

            nsk_jvmti_setFailStatus();

        }

        if (!checkBytecode("original", class_data_len, class_data,

                                        origClassSize, origClassBytes, NSK_TRUE)) {

            nsk_jvmti_setFailStatus();

        }

    }

}

/* ============================================================================= */

/** Agent library initialization. */

#ifdef STATIC_BUILD

JNIEXPORT jint JNICALL Agent_OnLoad_classfloadhk002(JavaVM *jvm, char *options, void *reserved) {

    return Agent_Initialize(jvm, options, reserved);

}

JNIEXPORT jint JNICALL Agent_OnAttach_classfloadhk002(JavaVM *jvm, char *options, void *reserved) {

    return Agent_Initialize(jvm, options, reserved);

}

JNIEXPORT jint JNI_OnLoad_classfloadhk002(JavaVM *jvm, char *options, void *reserved) {

    return JNI_VERSION_1_8;

}

#endif

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

    jvmtiEnv* jvmti = NULL;

    /* init framework and parse options */

    if (!NSK_VERIFY(nsk_jvmti_parseOptions(options)))

        return JNI_ERR;

    timeout = nsk_jvmti_getWaitTime() * 60 * 1000;

    /* create JVMTI environment */

    if (!NSK_VERIFY((jvmti =

            nsk_jvmti_createJVMTIEnv(jvm, reserved)) != NULL))

        return JNI_ERR;

    NSK_DISPLAY1("Add required capability: %s\n", "can_generate_eraly_class_hook_events");

    {

        jvmtiCapabilities caps;

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

        caps.can_generate_all_class_hook_events = 1;

        if (!NSK_JVMTI_VERIFY(

                NSK_CPP_STUB2(AddCapabilities, jvmti, &caps))) {

            return JNI_ERR;

        }

    }

    NSK_DISPLAY0("  ... added\n");

    NSK_DISPLAY1("Set callback for event: %s\n", "CLASS_FILE_LOAD_HOOK");

    {

        jvmtiEventCallbacks callbacks;

        jint size = (jint)sizeof(callbacks);

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

        callbacks.ClassFileLoadHook = callbackClassFileLoadHook;

        if (!NSK_JVMTI_VERIFY(

                NSK_CPP_STUB3(SetEventCallbacks, jvmti, &callbacks, size))) {

            return JNI_ERR;

        }

    }

    NSK_DISPLAY0("  ... set\n");

    /* register agent proc and arg */

    if (!NSK_VERIFY(nsk_jvmti_setAgentProc(agentProc, NULL)))

        return JNI_ERR;

    return JNI_OK;

}

/* ============================================================================= */

}