FileDescriptor_md.c

/*
 * Copyright (c) 1997, 2017, 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 <unistd.h>
#include <fcntl.h>

#include "jni.h"
#include "jni_util.h"
#include "jvm.h"

#include "io_util_md.h"
#include "java_io_FileDescriptor.h"

/*******************************************************************/
/*  BEGIN JNI ********* BEGIN JNI *********** BEGIN JNI ************/
/*******************************************************************/

/* field id for jint 'fd' in java.io.FileDescriptor */
jfieldID IO_fd_fdID;

/* field id for jboolean 'append' in java.io.FileDescriptor */
jfieldID IO_append_fdID;

/**************************************************************
 * static methods to store field ID's in initializers
 */

JNIEXPORT void JNICALL
Java_java_io_FileDescriptor_initIDs(JNIEnv *env, jclass fdClass) {
    CHECK_NULL(IO_fd_fdID = (*env)->GetFieldID(env, fdClass, "fd", "I"));
    CHECK_NULL(IO_append_fdID = (*env)->GetFieldID(env, fdClass, "append", "Z"));
}

/**************************************************************
 * File Descriptor
 */

JNIEXPORT void JNICALL
Java_java_io_FileDescriptor_sync(JNIEnv *env, jobject this) {
    FD fd = THIS_FD(this);
    if (IO_Sync(fd) == -1) {
        JNU_ThrowByName(env, "java/io/SyncFailedException", "sync failed");
    }
}
JNIEXPORT jlong JNICALL
Java_java_io_FileDescriptor_getHandle(JNIEnv *env, jclass fdClass, jint fd) {
    return -1;
}

JNIEXPORT jboolean JNICALL
Java_java_io_FileDescriptor_getAppend(JNIEnv *env, jclass fdClass, jint fd) {
    int flags = fcntl(fd, F_GETFL);
    return ((flags & O_APPEND) == 0) ? JNI_FALSE : JNI_TRUE;
}

// instance method close0 for FileDescriptor
JNIEXPORT void JNICALL
Java_java_io_FileDescriptor_close0(JNIEnv *env, jobject this) {
    fileDescriptorClose(env, this);
}

JNIEXPORT void JNICALL
Java_java_io_FileCleanable_cleanupClose0(JNIEnv *env, jclass fdClass, jint fd, jlong unused) {
    if (fd != -1) {
        if (close(fd) == -1) {
            JNU_ThrowIOExceptionWithLastError(env, "close failed");
        }
    }
}