/*

 * Copyright (c) 1996, 2015, 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.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * 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 <assert.h>

#include "jni.h"

#include "jni_util.h"

#include "jlong.h"

#include "jvm.h"

#include "java_lang_ClassLoader.h"

#include "java_lang_ClassLoader_NativeLibrary.h"

#include <string.h>

/* defined in libverify.so/verify.dll (src file common/check_format.c) */

extern jboolean VerifyClassname(char *utf_name, jboolean arrayAllowed);

extern jboolean VerifyFixClassname(char *utf_name);

static JNINativeMethod methods[] = {

    {"retrieveDirectives",  "()Ljava/lang/AssertionStatusDirectives;", (void *)&JVM_AssertionStatusDirectives}

};

JNIEXPORT void JNICALL

Java_java_lang_ClassLoader_registerNatives(JNIEnv *env, jclass cls)

{

    (*env)->RegisterNatives(env, cls, methods,

                            sizeof(methods)/sizeof(JNINativeMethod));

}

/* Convert java string to UTF char*. Use local buffer if possible,

   otherwise malloc new memory. Returns null IFF malloc failed. */

static char*

getUTF(JNIEnv *env, jstring str, char* localBuf, int bufSize)

{

    char* utfStr = NULL;

    int len = (*env)->GetStringUTFLength(env, str);

    int unicode_len = (*env)->GetStringLength(env, str);

    if (len >= bufSize) {

        utfStr = malloc(len + 1);

        if (utfStr == NULL) {

            JNU_ThrowOutOfMemoryError(env, NULL);

            return NULL;

        }

    } else {

        utfStr = localBuf;

    }

    (*env)->GetStringUTFRegion(env, str, 0, unicode_len, utfStr);

    return utfStr;

}

JNIEXPORT jclass JNICALL

Java_java_lang_ClassLoader_defineClass1(JNIEnv *env,

                                        jclass cls,

                                        jobject loader,

                                        jstring name,

                                        jbyteArray data,

                                        jint offset,

                                        jint length,

                                        jobject pd,

                                        jstring source)

{

    jbyte *body;

    char *utfName;

    jclass result = 0;

    char buf[128];

    char* utfSource;

    char sourceBuf[1024];

    if (data == NULL) {

        JNU_ThrowNullPointerException(env, 0);

        return 0;

    }

    /* Work around 4153825. malloc crashes on Solaris when passed a

     * negative size.

     */

    if (length < 0) {

        JNU_ThrowArrayIndexOutOfBoundsException(env, 0);

        return 0;

    }

    body = (jbyte *)malloc(length);

    if (body == 0) {

        JNU_ThrowOutOfMemoryError(env, 0);

        return 0;

    }

    (*env)->GetByteArrayRegion(env, data, offset, length, body);

    if ((*env)->ExceptionOccurred(env))

        goto free_body;

    if (name != NULL) {

        utfName = getUTF(env, name, buf, sizeof(buf));

        if (utfName == NULL) {

            goto free_body;

        }

        VerifyFixClassname(utfName);

    } else {

        utfName = NULL;

    }

    if (source != NULL) {

        utfSource = getUTF(env, source, sourceBuf, sizeof(sourceBuf));

        if (utfSource == NULL) {

            goto free_utfName;

        }

    } else {

        utfSource = NULL;

    }

    result = JVM_DefineClassWithSource(env, utfName, loader, body, length, pd, utfSource);

    if (utfSource && utfSource != sourceBuf)

        free(utfSource);

 free_utfName:

    if (utfName && utfName != buf)

        free(utfName);

 free_body:

    free(body);

    return result;

}

JNIEXPORT jclass JNICALL

Java_java_lang_ClassLoader_defineClass2(JNIEnv *env,

                                        jclass cls,

                                        jobject loader,

                                        jstring name,

                                        jobject data,

                                        jint offset,

                                        jint length,

                                        jobject pd,

                                        jstring source)

{

    jbyte *body;

    char *utfName;

    jclass result = 0;

    char buf[128];

    char* utfSource;

    char sourceBuf[1024];

    assert(data != NULL); // caller fails if data is null.

    assert(length >= 0);  // caller passes ByteBuffer.remaining() for length, so never neg.

    // caller passes ByteBuffer.position() for offset, and capacity() >= position() + remaining()

    assert((*env)->GetDirectBufferCapacity(env, data) >= (offset + length));

    body = (*env)->GetDirectBufferAddress(env, data);

    if (body == 0) {

        JNU_ThrowNullPointerException(env, 0);

        return 0;

    }

    body += offset;

    if (name != NULL) {

        utfName = getUTF(env, name, buf, sizeof(buf));

        if (utfName == NULL) {

            JNU_ThrowOutOfMemoryError(env, NULL);

            return result;

        }

        VerifyFixClassname(utfName);

    } else {

        utfName = NULL;

    }

    if (source != NULL) {

        utfSource = getUTF(env, source, sourceBuf, sizeof(sourceBuf));

        if (utfSource == NULL) {

            JNU_ThrowOutOfMemoryError(env, NULL);

            goto free_utfName;

        }

    } else {

        utfSource = NULL;

    }

    result = JVM_DefineClassWithSource(env, utfName, loader, body, length, pd, utfSource);

    if (utfSource && utfSource != sourceBuf)

        free(utfSource);

 free_utfName:

    if (utfName && utfName != buf)

        free(utfName);

    return result;

}

/*

 * Returns NULL if class not found.

 */

JNIEXPORT jclass JNICALL

Java_java_lang_ClassLoader_findBootstrapClass(JNIEnv *env, jobject loader,

                                              jstring classname)

{

    char *clname;

    jclass cls = 0;

    char buf[128];

    if (classname == NULL) {

        return 0;

    }

    clname = getUTF(env, classname, buf, sizeof(buf));

    if (clname == NULL) {

        JNU_ThrowOutOfMemoryError(env, NULL);

        return NULL;

    }

    VerifyFixClassname(clname);

    if (!VerifyClassname(clname, JNI_TRUE)) {  /* expects slashed name */

        goto done;

    }

    cls = JVM_FindClassFromBootLoader(env, clname);

 done:

    if (clname != buf) {

        free(clname);

    }

    return cls;

}

JNIEXPORT jclass JNICALL

Java_java_lang_ClassLoader_findLoadedClass0(JNIEnv *env, jobject loader,

                                           jstring name)

{

    if (name == NULL) {

        return 0;

    } else {

        return JVM_FindLoadedClass(env, loader, name);

    }

}

static jfieldID handleID;

static jfieldID jniVersionID;

static void *procHandle;

static jboolean initIDs(JNIEnv *env)

{

    if (handleID == 0) {

        jclass this =

            (*env)->FindClass(env, "java/lang/ClassLoader$NativeLibrary");

        if (this == 0)

            return JNI_FALSE;

        handleID = (*env)->GetFieldID(env, this, "handle", "J");

        if (handleID == 0)

            return JNI_FALSE;

        jniVersionID = (*env)->GetFieldID(env, this, "jniVersion", "I");

        if (jniVersionID == 0)

            return JNI_FALSE;

        procHandle = getProcessHandle();

    }

    return JNI_TRUE;

}

typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);

typedef void (JNICALL *JNI_OnUnload_t)(JavaVM *, void *);

/*

 * Support for finding JNI_On(Un)Load_<lib_name> if it exists.

 * If cname == NULL then just find normal JNI_On(Un)Load entry point

 */

static void *findJniFunction(JNIEnv *env, void *handle,

                                    const char *cname, jboolean isLoad) {

    const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS;

    const char *onUnloadSymbols[] = JNI_ONUNLOAD_SYMBOLS;

    const char **syms;

    int symsLen;

    void *entryName = NULL;

    char *jniFunctionName;

    int i;

    size_t len;

    // Check for JNI_On(Un)Load<_libname> function

    if (isLoad) {

        syms = onLoadSymbols;

        symsLen = sizeof(onLoadSymbols) / sizeof(char *);

    } else {

        syms = onUnloadSymbols;

        symsLen = sizeof(onUnloadSymbols) / sizeof(char *);

    }

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

        // cname + sym + '_' + '\0'

        if ((len = (cname != NULL ? strlen(cname) : 0) + strlen(syms[i]) + 2) >

            FILENAME_MAX) {

            goto done;

        }

        jniFunctionName = malloc(len);

        if (jniFunctionName == NULL) {

            JNU_ThrowOutOfMemoryError(env, NULL);

            goto done;

        }

        buildJniFunctionName(syms[i], cname, jniFunctionName);

        entryName = JVM_FindLibraryEntry(handle, jniFunctionName);

        free(jniFunctionName);

        if(entryName) {

            break;

        }

    }

 done:

    return entryName;

}

/*

 * Class:     java_lang_ClassLoader_NativeLibrary

 */

  (JNIEnv *env, jobject this, jstring name, jboolean isBuiltin)

{

    const char *cname;

    jint jniVersion;

    jthrowable cause;

    void * handle;

    if (!initIDs(env))

    cname = JNU_GetStringPlatformChars(env, name, 0);

    if (cname == 0)

    handle = isBuiltin ? procHandle : JVM_LoadLibrary(cname);

    if (handle) {

        JNI_OnLoad_t JNI_OnLoad;

        JNI_OnLoad = (JNI_OnLoad_t)findJniFunction(env, handle,

        if (JNI_OnLoad) {

            JavaVM *jvm;

            (*env)->GetJavaVM(env, &jvm);

            jniVersion = (*JNI_OnLoad)(jvm, NULL);

        } else {

            jniVersion = 0x00010001;

        }

        cause = (*env)->ExceptionOccurred(env);

        if (cause) {

            (*env)->ExceptionClear(env);

            (*env)->Throw(env, cause);

            if (!isBuiltin) {

                JVM_UnloadLibrary(handle);

            }

            goto done;

        }

        if (!JVM_IsSupportedJNIVersion(jniVersion) ||

            (isBuiltin && jniVersion < JNI_VERSION_1_8)) {

            char msg[256];

            jio_snprintf(msg, sizeof(msg),

                         "unsupported JNI version 0x%08X required by %s",

                         jniVersion, cname);

            JNU_ThrowByName(env, "java/lang/UnsatisfiedLinkError", msg);

            if (!isBuiltin) {

                JVM_UnloadLibrary(handle);

            }

            goto done;

        }

        (*env)->SetIntField(env, this, jniVersionID, jniVersion);

    } else {

        cause = (*env)->ExceptionOccurred(env);

        if (cause) {

            (*env)->ExceptionClear(env);

            (*env)->SetLongField(env, this, handleID, (jlong)0);

            (*env)->Throw(env, cause);

        }

        goto done;

    }

    (*env)->SetLongField(env, this, handleID, ptr_to_jlong(handle));

 done:

    JNU_ReleaseStringPlatformChars(env, name, cname);

}

/*

 * Class:     java_lang_ClassLoader_NativeLibrary

 * Method:    unload

 */

JNIEXPORT void JNICALL

Java_java_lang_ClassLoader_00024NativeLibrary_unload

{

    const char *onUnloadSymbols[] = JNI_ONUNLOAD_SYMBOLS;

    void *handle;

    JNI_OnUnload_t JNI_OnUnload;

     const char *cname;

    if (!initIDs(env))

        return;

    cname = JNU_GetStringPlatformChars(env, name, 0);

    if (cname == NULL) {

        return;

    }

    JNI_OnUnload = (JNI_OnUnload_t )findJniFunction(env, handle,

    if (JNI_OnUnload) {

        JavaVM *jvm;

        (*env)->GetJavaVM(env, &jvm);

        (*JNI_OnUnload)(jvm, NULL);

    }

    if (!isBuiltin) {

        JVM_UnloadLibrary(handle);

    }

    JNU_ReleaseStringPlatformChars(env, name, cname);

}

/*

 * Class:     java_lang_ClassLoader_NativeLibrary

 * Signature: (Ljava/lang/String;)J

 */

JNIEXPORT jlong JNICALL

  (JNIEnv *env, jobject this, jstring name)

{

    jlong handle;

    const char *cname;

    jlong res;

    if (!initIDs(env))

        return jlong_zero;

    handle = (*env)->GetLongField(env, this, handleID);

    cname = (*env)->GetStringUTFChars(env, name, 0);

    if (cname == 0)

        return jlong_zero;

    res = ptr_to_jlong(JVM_FindLibraryEntry(jlong_to_ptr(handle), cname));

    (*env)->ReleaseStringUTFChars(env, name, cname);

    return res;

}

/*

 * Class:     java_lang_ClassLoader

 * Method:    findBuiltinLib

 * Signature: (Ljava/lang/String;)Ljava/lang/String;

 */

JNIEXPORT jstring JNICALL

Java_java_lang_ClassLoader_findBuiltinLib

  (JNIEnv *env, jclass cls, jstring name)

{

    const char *cname;

    char *libName;

    size_t prefixLen = strlen(JNI_LIB_PREFIX);

    size_t suffixLen = strlen(JNI_LIB_SUFFIX);

    size_t len;

    jstring lib;

    void *ret;

    const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS;

    if (name == NULL) {

        JNU_ThrowInternalError(env, "NULL filename for native library");

        return NULL;

    }

    procHandle = getProcessHandle();

    cname = JNU_GetStringPlatformChars(env, name, 0);

    if (cname == NULL) {

        return NULL;

    }

    // Copy name Skipping PREFIX

    len = strlen(cname);

    if (len <= (prefixLen+suffixLen)) {

        JNU_ReleaseStringPlatformChars(env, name, cname);

        return NULL;

    }

    libName = malloc(len + 1); //+1 for null if prefix+suffix == 0

    if (libName == NULL) {

        JNU_ReleaseStringPlatformChars(env, name, cname);

        JNU_ThrowOutOfMemoryError(env, NULL);

        return NULL;

    }

    if (len > prefixLen) {

        strcpy(libName, cname+prefixLen);

    }

    JNU_ReleaseStringPlatformChars(env, name, cname);

    // Strip SUFFIX

    libName[strlen(libName)-suffixLen] = '\0';

    // Check for JNI_OnLoad_libname function