/*

 * Copyright (c) 2019, 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 "jni.h"

#include "jni_util.h"

#include "jvm.h"

#include "jlong.h"

#include <netdb.h>

#include <sys/types.h>

#include <sys/socket.h>

#include <stdlib.h>

#include <string.h>

#include <errno.h>

#if defined(__linux__) || defined(_ALLBSD_SOURCE)

#include <netinet/in.h>

#endif

#include "net_util.h"

#include "net_util_md.h"

#include "nio.h"

#include "nio_util.h"

#include "sun_nio_ch_NioDatagramSocketImpl.h"

static jfieldID dsi_senderID;   /* sender in sun.nio.ch.NioDatagramSocketImpl */

static jclass isa_class;        /* java.net.InetSocketAddress */

static jmethodID isa_ctorID;    /* InetSocketAddress(InetAddress, int) */

JNIEXPORT void JNICALL

Java_sun_nio_ch_NioDatagramSocketImpl_initIDs(JNIEnv *env, jclass clazz)

{

    clazz = (*env)->FindClass(env, "java/net/InetSocketAddress");

    CHECK_NULL(clazz);

    isa_class = (*env)->NewGlobalRef(env, clazz);

    if (isa_class == NULL) {

        JNU_ThrowOutOfMemoryError(env, NULL);

        return;

    }

    isa_ctorID = (*env)->GetMethodID(env, clazz, "<init>", "(Ljava/net/InetAddress;I)V");

    CHECK_NULL(isa_ctorID);

    clazz = (*env)->FindClass(env, "sun/nio/ch/NioDatagramSocketImpl");

    CHECK_NULL(clazz);

    dsi_senderID = (*env)->GetFieldID(env, clazz, "sender", "Ljava/net/InetSocketAddress;");

    CHECK_NULL(dsi_senderID);

}

JNIEXPORT jint JNICALL

Java_sun_nio_ch_NioDatagramSocketImpl_send0(JNIEnv *env,

                                            jclass clazz,

                                            jboolean preferIPv6,

                                            jobject fdo,

                                            jlong address,

                                            jint len,

                                            jobject destAddress,

                                            jint destPort)

{

    jint fd = fdval(env, fdo);

    void *buf = (void *)jlong_to_ptr(address);

    SOCKETADDRESS sa;

    struct sockaddr *saP = NULL;

    int sa_len = 0;

    jint n = 0;

    if (destAddress != NULL) {  // not connected

        if (NET_InetAddressToSockaddr(env, destAddress, destPort, &sa,

                                      &sa_len, preferIPv6) != 0) {

            return IOS_THROWN;

        }

        saP = &sa.sa;

    }

    n = sendto(fd, buf, len, 0, saP, sa_len);

    if (n < 0) {

        if (errno == EAGAIN || errno == EWOULDBLOCK) {

            return IOS_UNAVAILABLE;

        }

        if (errno == EINTR) {

            return IOS_INTERRUPTED;

        }

        if (errno == ECONNREFUSED) {

            JNU_ThrowByName(env, JNU_JAVANETPKG "PortUnreachableException", 0);

            return IOS_THROWN;

        }

        return handleSocketError(env, errno);

    }

    return n;

}

JNIEXPORT jint JNICALL

Java_sun_nio_ch_NioDatagramSocketImpl_receive0(JNIEnv *env,

                                               jobject this,

                                               jobject fdo,

                                               jlong address,

                                               jint len,

                                               jboolean isPeek,

                                               jobject cachedSenderAddress,

                                               jint cachedSenderPort)

{

    jint fd = fdval(env, fdo);

    void *buf = (void *)jlong_to_ptr(address);

    SOCKETADDRESS sa;

    socklen_t sa_len = sizeof(SOCKETADDRESS);

    jboolean retry = JNI_FALSE;

    int flags = 0;

    jint n = 0;

    jobject senderAddr;

    if (isPeek == JNI_TRUE) {

        flags = MSG_PEEK;

    }

    n = recvfrom(fd, buf, len, flags, &sa.sa, &sa_len);

    if (n < 0) {

        if (errno == EAGAIN || errno == EWOULDBLOCK) {

            return IOS_UNAVAILABLE;

        } else if (errno == EINTR) {

            return IOS_INTERRUPTED;

        } else if (errno == ECONNREFUSED) {

            JNU_ThrowByName(env, JNU_JAVANETPKG "PortUnreachableException",

                            "ICMP Port Unreachable");

            return IOS_THROWN;

        } else {

            return handleSocketError(env, errno);

        }

    }

    // If the cached address does not match, then create a new one.

    if (cachedSenderAddress == NULL ||

        !NET_SockaddrEqualsInetAddress(env, &sa, cachedSenderAddress) ||

        cachedSenderPort != NET_GetPortFromSockaddr(&sa)) {

        jobject isa = NULL;

        int port = 0;

        jobject ia = NET_SockaddrToInetAddress(env, &sa, &port);

        if (ia != NULL) {

            isa = (*env)->NewObject(env, isa_class, isa_ctorID, ia, port);

        }

        CHECK_NULL_RETURN(isa, IOS_THROWN);

        (*env)->SetObjectField(env, this, dsi_senderID, isa);

    }

    return n;

}

JNIEXPORT void JNICALL

Java_sun_nio_ch_NioDatagramSocketImpl_disconnect0(JNIEnv *env,

                                                 jobject clazz,

                                                 jobject fdo,

                                                 jboolean isIPv6)

{

    jint fd = fdval(env, fdo);

    int rv;

#if defined(__solaris__)

    rv = connect(fd, 0, 0);

#else

    SOCKETADDRESS sa;

    socklen_t len = isIPv6 ? sizeof(struct sockaddr_in6) :

                             sizeof(struct sockaddr_in);

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

#if defined(_ALLBSD_SOURCE)

    sa.sa.sa_family = isIPv6 ? AF_INET6 : AF_INET;

#else

    sa.sa.sa_family = AF_UNSPEC;

#endif

    rv = connect(fd, &sa.sa, len);

#if defined(_ALLBSD_SOURCE)

    if (rv < 0 && errno == EADDRNOTAVAIL)

        rv = errno = 0;

#elif defined(_AIX)

    /* See W. Richard Stevens, "UNIX Network Programming, Volume 1", p. 254:

     * 'Setting the address family to AF_UNSPEC might return EAFNOSUPPORT

     * but that is acceptable.

     */

    if (rv < 0 && errno == EAFNOSUPPORT)

        rv = errno = 0;

#endif // defined(_ALLBSD_SOURCE) || defined(_AIX)

#endif // defined(__solaris__)

    if (rv < 0)

        handleSocketError(env, errno);

}