/*
 * Copyright 2000-2002 Sun Microsystems, Inc.  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.  Sun designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 */

#include "jni.h"
#include "jni_util.h"
#include "jvm.h"
#include "jlong.h"
#include "sun_nio_ch_FileDispatcher.h"
#include <sys/types.h>
#include <sys/socket.h>
#include <fcntl.h>
#include <sys/uio.h>
#include "nio_util.h"


static int preCloseFD = -1;     /* File descriptor to which we dup other fd's
                                   before closing them for real */


JNIEXPORT void JNICALL
Java_sun_nio_ch_FileDispatcher_init(JNIEnv *env, jclass cl)
{
    int sp[2];
    if (socketpair(PF_UNIX, SOCK_STREAM, 0, sp) < 0) {
        JNU_ThrowIOExceptionWithLastError(env, "socketpair failed");
        return;
    }
    preCloseFD = sp[0];
    close(sp[1]);
}

JNIEXPORT jint JNICALL
Java_sun_nio_ch_FileDispatcher_read0(JNIEnv *env, jclass clazz,
                             jobject fdo, jlong address, jint len)
{
    jint fd = fdval(env, fdo);
    void *buf = (void *)jlong_to_ptr(address);

    return convertReturnVal(env, read(fd, buf, len), JNI_TRUE);
}

JNIEXPORT jint JNICALL
Java_sun_nio_ch_FileDispatcher_pread0(JNIEnv *env, jclass clazz, jobject fdo,
                            jlong address, jint len, jlong offset)
{
    jint fd = fdval(env, fdo);
    void *buf = (void *)jlong_to_ptr(address);

    return convertReturnVal(env, pread64(fd, buf, len, offset), JNI_TRUE);
}

JNIEXPORT jlong JNICALL
Java_sun_nio_ch_FileDispatcher_readv0(JNIEnv *env, jclass clazz,
                              jobject fdo, jlong address, jint len)
{
    jint fd = fdval(env, fdo);
    struct iovec *iov = (struct iovec *)jlong_to_ptr(address);
    if (len > 16) {
        len = 16;
    }
    return convertLongReturnVal(env, readv(fd, iov, len), JNI_TRUE);
}

JNIEXPORT jint JNICALL
Java_sun_nio_ch_FileDispatcher_write0(JNIEnv *env, jclass clazz,
                              jobject fdo, jlong address, jint len)
{
    jint fd = fdval(env, fdo);
    void *buf = (void *)jlong_to_ptr(address);

    return convertReturnVal(env, write(fd, buf, len), JNI_FALSE);
}

JNIEXPORT jint JNICALL
Java_sun_nio_ch_FileDispatcher_pwrite0(JNIEnv *env, jclass clazz, jobject fdo,
                            jlong address, jint len, jlong offset)
{
    jint fd = fdval(env, fdo);
    void *buf = (void *)jlong_to_ptr(address);

    return convertReturnVal(env, pwrite64(fd, buf, len, offset), JNI_FALSE);
}

JNIEXPORT jlong JNICALL
Java_sun_nio_ch_FileDispatcher_writev0(JNIEnv *env, jclass clazz,
                                       jobject fdo, jlong address, jint len)
{
    jint fd = fdval(env, fdo);
    struct iovec *iov = (struct iovec *)jlong_to_ptr(address);
    if (len > 16) {
        len = 16;
    }
    return convertLongReturnVal(env, writev(fd, iov, len), JNI_FALSE);
}

static void closeFileDescriptor(JNIEnv *env, int fd) {
    if (fd != -1) {
        int result = close(fd);
        if (result < 0)
            JNU_ThrowIOExceptionWithLastError(env, "Close failed");
    }
}

JNIEXPORT void JNICALL
Java_sun_nio_ch_FileDispatcher_close0(JNIEnv *env, jclass clazz, jobject fdo)
{
    jint fd = fdval(env, fdo);
    closeFileDescriptor(env, fd);
}

JNIEXPORT void JNICALL
Java_sun_nio_ch_FileDispatcher_preClose0(JNIEnv *env, jclass clazz, jobject fdo)
{
    jint fd = fdval(env, fdo);
    if (preCloseFD >= 0) {
        if (dup2(preCloseFD, fd) < 0)
            JNU_ThrowIOExceptionWithLastError(env, "dup2 failed");
    }
}

JNIEXPORT void JNICALL
Java_sun_nio_ch_FileDispatcher_closeIntFD(JNIEnv *env, jclass clazz, jint fd)
{
    closeFileDescriptor(env, fd);
}