alvinalexander.com | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Java example source code file (net_util_md.c)

This example Java source code file (net_util_md.c) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

af_inet6, check_null, fail_if_not_enobufs, fd_set, file, ipproto_ip, jni_false, jni_true, null, so_rcvbuf, so_sndbuf, sock_dgram, sock_stream, sol_socket

The net_util_md.c Java example source code

/*
 * Copyright (c) 1997, 2013, 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 <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/tcp.h>        /* Defines TCP_NODELAY, needed for 2.6 */
#include <netinet/in.h>
#include <net/if.h>
#include <netdb.h>
#include <stdlib.h>
#include <dlfcn.h>

#ifndef _ALLBSD_SOURCE
#include <values.h>
#else
#include <limits.h>
#include <sys/param.h>
#include <sys/sysctl.h>
#ifndef MAXINT
#define MAXINT INT_MAX
#endif
#endif

#ifdef __solaris__
#include <sys/sockio.h>
#include <stropts.h>
#include <inet/nd.h>
#endif

#ifdef __linux__
#include <arpa/inet.h>
#include <net/route.h>
#include <sys/utsname.h>

#ifndef IPV6_FLOWINFO_SEND
#define IPV6_FLOWINFO_SEND      33
#endif

#endif

#include "jni_util.h"
#include "jvm.h"
#include "net_util.h"

#include "java_net_SocketOptions.h"

/* needed from libsocket on Solaris 8 */

getaddrinfo_f getaddrinfo_ptr = NULL;
freeaddrinfo_f freeaddrinfo_ptr = NULL;
gai_strerror_f gai_strerror_ptr = NULL;
getnameinfo_f getnameinfo_ptr = NULL;

/*
 * EXCLBIND socket options only on Solaris
 */
#if defined(__solaris__) && !defined(TCP_EXCLBIND)
#define TCP_EXCLBIND            0x21
#endif
#if defined(__solaris__) && !defined(UDP_EXCLBIND)
#define UDP_EXCLBIND            0x0101
#endif

void setDefaultScopeID(JNIEnv *env, struct sockaddr *him)
{
#ifdef MACOSX
    static jclass ni_class = NULL;
    static jfieldID ni_defaultIndexID;
    if (ni_class == NULL) {
        jclass c = (*env)->FindClass(env, "java/net/NetworkInterface");
        CHECK_NULL(c);
        c = (*env)->NewGlobalRef(env, c);
        CHECK_NULL(c);
        ni_defaultIndexID = (*env)->GetStaticFieldID(
            env, c, "defaultIndex", "I");
        ni_class = c;
    }
    int defaultIndex;
    struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)him;
    if (sin6->sin6_family == AF_INET6 && (sin6->sin6_scope_id == 0)) {
        defaultIndex = (*env)->GetStaticIntField(env, ni_class,
                                                 ni_defaultIndexID);
        sin6->sin6_scope_id = defaultIndex;
    }
#endif
}

int getDefaultScopeID(JNIEnv *env) {
    static jclass ni_class = NULL;
    static jfieldID ni_defaultIndexID;
    if (ni_class == NULL) {
        jclass c = (*env)->FindClass(env, "java/net/NetworkInterface");
        CHECK_NULL_RETURN(c, 0);
        c = (*env)->NewGlobalRef(env, c);
        CHECK_NULL_RETURN(c, 0);
        ni_defaultIndexID = (*env)->GetStaticFieldID(env, c,
                                                     "defaultIndex", "I");
        ni_class = c;
    }
    int defaultIndex = 0;
    defaultIndex = (*env)->GetStaticIntField(env, ni_class,
                                             ni_defaultIndexID);
    return defaultIndex;
}

#ifdef __solaris__
static int init_tcp_max_buf, init_udp_max_buf;
static int tcp_max_buf;
static int udp_max_buf;
static int useExclBind = 0;

/*
 * Get the specified parameter from the specified driver. The value
 * of the parameter is assumed to be an 'int'. If the parameter
 * cannot be obtained return -1
 */
int net_getParam(char *driver, char *param)
{
    struct strioctl stri;
    char buf [64];
    int s;
    int value;

    s = open (driver, O_RDWR);
    if (s < 0) {
        return -1;
    }
    strncpy (buf, param, sizeof(buf));
    stri.ic_cmd = ND_GET;
    stri.ic_timout = 0;
    stri.ic_dp = buf;
    stri.ic_len = sizeof(buf);
    if (ioctl (s, I_STR, &stri) < 0) {
        value = -1;
    } else {
        value = atoi(buf);
    }
    close (s);
    return value;
}

/*
 * Iterative way to find the max value that SO_SNDBUF or SO_RCVBUF
 * for Solaris versions that do not support the ioctl() in net_getParam().
 * Ugly, but only called once (for each sotype).
 *
 * As an optimization, we make a guess using the default values for Solaris
 * assuming they haven't been modified with ndd.
 */

#define MAX_TCP_GUESS 1024 * 1024
#define MAX_UDP_GUESS 2 * 1024 * 1024

#define FAIL_IF_NOT_ENOBUFS if (errno != ENOBUFS) return -1

static int findMaxBuf(int fd, int opt, int sotype) {
    int a = 0;
    int b = MAXINT;
    int initial_guess;
    int limit = -1;

    if (sotype == SOCK_DGRAM) {
        initial_guess = MAX_UDP_GUESS;
    } else {
        initial_guess = MAX_TCP_GUESS;
    }

    if (setsockopt(fd, SOL_SOCKET, opt, &initial_guess, sizeof(int)) == 0) {
        initial_guess++;
        if (setsockopt(fd, SOL_SOCKET, opt, &initial_guess,sizeof(int)) < 0) {
            FAIL_IF_NOT_ENOBUFS;
            return initial_guess - 1;
        }
        a = initial_guess;
    } else {
        FAIL_IF_NOT_ENOBUFS;
        b = initial_guess - 1;
    }
    do {
        int mid = a + (b-a)/2;
        if (setsockopt(fd, SOL_SOCKET, opt, &mid, sizeof(int)) == 0) {
            limit = mid;
            a = mid + 1;
        } else {
            FAIL_IF_NOT_ENOBUFS;
            b = mid - 1;
        }
    } while (b >= a);

    return limit;
}
#endif

#ifdef __linux__
static int vinit = 0;
static int kernelV24 = 0;
static int vinit24 = 0;

int kernelIsV24 () {
    if (!vinit24) {
        struct utsname sysinfo;
        if (uname(&sysinfo) == 0) {
            sysinfo.release[3] = '\0';
            if (strcmp(sysinfo.release, "2.4") == 0) {
                kernelV24 = JNI_TRUE;
            }
        }
        vinit24 = 1;
    }
    return kernelV24;
}

int getScopeID (struct sockaddr *him) {
    struct sockaddr_in6 *hext = (struct sockaddr_in6 *)him;
    return hext->sin6_scope_id;
}

int cmpScopeID (unsigned int scope, struct sockaddr *him) {
    struct sockaddr_in6 *hext = (struct sockaddr_in6 *)him;
    return hext->sin6_scope_id == scope;
}

#else

int getScopeID (struct sockaddr *him) {
    struct sockaddr_in6 *him6 = (struct sockaddr_in6 *)him;
    return him6->sin6_scope_id;
}

int cmpScopeID (unsigned int scope, struct sockaddr *him) {
    struct sockaddr_in6 *him6 = (struct sockaddr_in6 *)him;
    return him6->sin6_scope_id == scope;
}

#endif


void
NET_ThrowByNameWithLastError(JNIEnv *env, const char *name,
                   const char *defaultDetail) {
    char errmsg[255];
    sprintf(errmsg, "errno: %d, error: %s\n", errno, defaultDetail);
    JNU_ThrowByNameWithLastError(env, name, errmsg);
}

void
NET_ThrowCurrent(JNIEnv *env, char *msg) {
    NET_ThrowNew(env, errno, msg);
}

void
NET_ThrowNew(JNIEnv *env, int errorNumber, char *msg) {
    char fullMsg[512];
    if (!msg) {
        msg = "no further information";
    }
    switch(errorNumber) {
    case EBADF:
        jio_snprintf(fullMsg, sizeof(fullMsg), "socket closed: %s", msg);
        JNU_ThrowByName(env, JNU_JAVANETPKG "SocketException", fullMsg);
        break;
    case EINTR:
        JNU_ThrowByName(env, JNU_JAVAIOPKG "InterruptedIOException", msg);
        break;
    default:
        errno = errorNumber;
        JNU_ThrowByNameWithLastError(env, JNU_JAVANETPKG "SocketException", msg);
        break;
    }
}


jfieldID
NET_GetFileDescriptorID(JNIEnv *env)
{
    jclass cls = (*env)->FindClass(env, "java/io/FileDescriptor");
    CHECK_NULL_RETURN(cls, NULL);
    return (*env)->GetFieldID(env, cls, "fd", "I");
}

#if defined(DONT_ENABLE_IPV6)
jint  IPv6_supported()
{
    return JNI_FALSE;
}

#else /* !DONT_ENABLE_IPV6 */

jint  IPv6_supported()
{
#ifndef AF_INET6
    return JNI_FALSE;
#endif

#ifdef AF_INET6
    int fd;
    void *ipv6_fn;
    SOCKADDR sa;
    socklen_t sa_len = sizeof(sa);

    fd = JVM_Socket(AF_INET6, SOCK_STREAM, 0) ;
    if (fd < 0) {
        /*
         *  TODO: We really cant tell since it may be an unrelated error
         *  for now we will assume that AF_INET6 is not available
         */
        return JNI_FALSE;
    }

    /*
     * If fd 0 is a socket it means we've been launched from inetd or
     * xinetd. If it's a socket then check the family - if it's an
     * IPv4 socket then we need to disable IPv6.
     */
    if (getsockname(0, (struct sockaddr *)&sa, &sa_len) == 0) {
        struct sockaddr *saP = (struct sockaddr *)&sa;
        if (saP->sa_family != AF_INET6) {
            return JNI_FALSE;
        }
    }

    /**
     * Linux - check if any interface has an IPv6 address.
     * Don't need to parse the line - we just need an indication.
     */
#ifdef __linux__
    {
        FILE *fP = fopen("/proc/net/if_inet6", "r");
        char buf[255];
        char *bufP;

        if (fP == NULL) {
            close(fd);
            return JNI_FALSE;
        }
        bufP = fgets(buf, sizeof(buf), fP);
        fclose(fP);
        if (bufP == NULL) {
            close(fd);
            return JNI_FALSE;
        }
    }
#endif

    /**
     * On Solaris 8 it's possible to create INET6 sockets even
     * though IPv6 is not enabled on all interfaces. Thus we
     * query the number of IPv6 addresses to verify that IPv6
     * has been configured on at least one interface.
     *
     * On Linux it doesn't matter - if IPv6 is built-in the
     * kernel then IPv6 addresses will be bound automatically
     * to all interfaces.
     */
#ifdef __solaris__

#ifdef SIOCGLIFNUM
    {
        struct lifnum numifs;

        numifs.lifn_family = AF_INET6;
        numifs.lifn_flags = 0;
        if (ioctl(fd, SIOCGLIFNUM, (char *)&numifs) < 0) {
            /**
             * SIOCGLIFNUM failed - assume IPv6 not configured
             */
            close(fd);
            return JNI_FALSE;
        }
        /**
         * If no IPv6 addresses then return false. If count > 0
         * it's possible that all IPv6 addresses are "down" but
         * that's okay as they may be brought "up" while the
         * VM is running.
         */
        if (numifs.lifn_count == 0) {
            close(fd);
            return JNI_FALSE;
        }
    }
#else
    /* SIOCGLIFNUM not defined in build environment ??? */
    close(fd);
    return JNI_FALSE;
#endif

#endif /* __solaris */

    /*
     *  OK we may have the stack available in the kernel,
     *  we should also check if the APIs are available.
     */
    ipv6_fn = JVM_FindLibraryEntry(RTLD_DEFAULT, "inet_pton");
    close(fd);
    if (ipv6_fn == NULL ) {
        return JNI_FALSE;
    } else {
        return JNI_TRUE;
    }
#endif /* AF_INET6 */
}
#endif /* DONT_ENABLE_IPV6 */

void ThrowUnknownHostExceptionWithGaiError(JNIEnv *env,
                                           const char* hostname,
                                           int gai_error)
{
    int size;
    char *buf;
    const char *format = "%s: %s";
    const char *error_string =
        (gai_strerror_ptr == NULL) ? NULL : (*gai_strerror_ptr)(gai_error);
    if (error_string == NULL)
        error_string = "unknown error";

    size = strlen(format) + strlen(hostname) + strlen(error_string) + 2;
    buf = (char *) malloc(size);
    if (buf) {
        jstring s;
        sprintf(buf, format, hostname, error_string);
        s = JNU_NewStringPlatform(env, buf);
        if (s != NULL) {
            jobject x = JNU_NewObjectByName(env,
                                            "java/net/UnknownHostException",
                                            "(Ljava/lang/String;)V", s);
            if (x != NULL)
                (*env)->Throw(env, x);
        }
        free(buf);
    }
}

void
NET_AllocSockaddr(struct sockaddr **him, int *len) {
#ifdef AF_INET6
    if (ipv6_available()) {
        struct sockaddr_in6 *him6 = (struct sockaddr_in6*)malloc(sizeof(struct sockaddr_in6));
        *him = (struct sockaddr*)him6;
        *len = sizeof(struct sockaddr_in6);
    } else
#endif /* AF_INET6 */
        {
            struct sockaddr_in *him4 = (struct sockaddr_in*)malloc(sizeof(struct sockaddr_in));
            *him = (struct sockaddr*)him4;
            *len = sizeof(struct sockaddr_in);
        }
}

#if defined(__linux__) && defined(AF_INET6)


/* following code creates a list of addresses from the kernel
 * routing table that are routed via the loopback address.
 * We check all destination addresses against this table
 * and override the scope_id field to use the relevant value for "lo"
 * in order to work-around the Linux bug that prevents packets destined
 * for certain local addresses from being sent via a physical interface.
 */

struct loopback_route {
    struct in6_addr addr; /* destination address */
    int plen; /* prefix length */
};

static struct loopback_route *loRoutes = 0;
static int nRoutes = 0; /* number of routes */
static int loRoutes_size = 16; /* initial size */
static int lo_scope_id = 0;

static void initLoopbackRoutes();

void printAddr (struct in6_addr *addr) {
    int i;
    for (i=0; i<16; i++) {
        printf ("%02x", addr->s6_addr[i]);
    }
    printf ("\n");
}

static jboolean needsLoopbackRoute (struct in6_addr* dest_addr) {
    int byte_count;
    int extra_bits, i;
    struct loopback_route *ptr;

    if (loRoutes == 0) {
        initLoopbackRoutes();
    }

    for (ptr = loRoutes, i=0; i<nRoutes; i++, ptr++) {
        struct in6_addr *target_addr=&ptr->addr;
        int dest_plen = ptr->plen;
        byte_count = dest_plen >> 3;
        extra_bits = dest_plen & 0x3;

        if (byte_count > 0) {
            if (memcmp(target_addr, dest_addr, byte_count)) {
                continue;  /* no match */
            }
        }

        if (extra_bits > 0) {
            unsigned char c1 = ((unsigned char *)target_addr)[byte_count];
            unsigned char c2 = ((unsigned char *)&dest_addr)[byte_count];
            unsigned char mask = 0xff << (8 - extra_bits);
            if ((c1 & mask) != (c2 & mask)) {
                continue;
            }
        }
        return JNI_TRUE;
    }
    return JNI_FALSE;
}


static void initLoopbackRoutes() {
    FILE *f;
    char srcp[8][5];
    char hopp[8][5];
    int dest_plen, src_plen, use, refcnt, metric;
    unsigned long flags;
    char dest_str[40];
    struct in6_addr dest_addr;
    char device[16];
    struct loopback_route *loRoutesTemp;

    if (loRoutes != 0) {
        free (loRoutes);
    }
    loRoutes = calloc (loRoutes_size, sizeof(struct loopback_route));
    if (loRoutes == 0) {
        return;
    }
    /*
     * Scan /proc/net/ipv6_route looking for a matching
     * route.
     */
    if ((f = fopen("/proc/net/ipv6_route", "r")) == NULL) {
        return ;
    }
    while (fscanf(f, "%4s%4s%4s%4s%4s%4s%4s%4s %02x "
                     "%4s%4s%4s%4s%4s%4s%4s%4s %02x "
                     "%4s%4s%4s%4s%4s%4s%4s%4s "
                     "%08x %08x %08x %08lx %8s",
                     dest_str, &dest_str[5], &dest_str[10], &dest_str[15],
                     &dest_str[20], &dest_str[25], &dest_str[30], &dest_str[35],
                     &dest_plen,
                     srcp[0], srcp[1], srcp[2], srcp[3],
                     srcp[4], srcp[5], srcp[6], srcp[7],
                     &src_plen,
                     hopp[0], hopp[1], hopp[2], hopp[3],
                     hopp[4], hopp[5], hopp[6], hopp[7],
                     &metric, &use, &refcnt, &flags, device) == 31) {

        /*
         * Some routes should be ignored
         */
        if ( (dest_plen < 0 || dest_plen > 128)  ||
             (src_plen != 0) ||
             (flags & (RTF_POLICY | RTF_FLOW)) ||
             ((flags & RTF_REJECT) && dest_plen == 0) ) {
            continue;
        }

        /*
         * Convert the destination address
         */
        dest_str[4] = ':';
        dest_str[9] = ':';
        dest_str[14] = ':';
        dest_str[19] = ':';
        dest_str[24] = ':';
        dest_str[29] = ':';
        dest_str[34] = ':';
        dest_str[39] = '\0';

        if (inet_pton(AF_INET6, dest_str, &dest_addr) < 0) {
            /* not an Ipv6 address */
            continue;
        }
        if (strcmp(device, "lo") != 0) {
            /* Not a loopback route */
            continue;
        } else {
            if (nRoutes == loRoutes_size) {
                loRoutesTemp = realloc (loRoutes, loRoutes_size *
                                        sizeof (struct loopback_route) * 2);

                if (loRoutesTemp == 0) {
                    free(loRoutes);
                    fclose (f);
                    return;
                }
                loRoutes=loRoutesTemp;
                loRoutes_size *= 2;
            }
            memcpy (&loRoutes[nRoutes].addr,&dest_addr,sizeof(struct in6_addr));
            loRoutes[nRoutes].plen = dest_plen;
            nRoutes ++;
        }
    }

    fclose (f);
    {
        /* now find the scope_id for "lo" */

        char devname[21];
        char addr6p[8][5];
        int plen, scope, dad_status, if_idx;

        if ((f = fopen("/proc/net/if_inet6", "r")) != NULL) {
            while (fscanf(f, "%4s%4s%4s%4s%4s%4s%4s%4s %08x %02x %02x %02x %20s\n",
                      addr6p[0], addr6p[1], addr6p[2], addr6p[3],
                      addr6p[4], addr6p[5], addr6p[6], addr6p[7],
                  &if_idx, &plen, &scope, &dad_status, devname) == 13) {

                if (strcmp(devname, "lo") == 0) {
                    /*
                     * Found - so just return the index
                     */
                    fclose(f);
                    lo_scope_id = if_idx;
                    return;
                }
            }
            fclose(f);
        }
    }
}

/*
 * Following is used for binding to local addresses. Equivalent
 * to code above, for bind().
 */

struct localinterface {
    int index;
    char localaddr [16];
};

static struct localinterface *localifs = 0;
static int localifsSize = 0;    /* size of array */
static int nifs = 0;            /* number of entries used in array */

/* not thread safe: make sure called once from one thread */

static void initLocalIfs () {
    FILE *f;
    unsigned char staddr [16];
    char ifname [33];
    struct localinterface *lif=0;
    int index, x1, x2, x3;
    unsigned int u0,u1,u2,u3,u4,u5,u6,u7,u8,u9,ua,ub,uc,ud,ue,uf;

    if ((f = fopen("/proc/net/if_inet6", "r")) == NULL) {
        return ;
    }
    while (fscanf (f, "%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x "
                "%d %x %x %x %32s",&u0,&u1,&u2,&u3,&u4,&u5,&u6,&u7,
                &u8,&u9,&ua,&ub,&uc,&ud,&ue,&uf,
                &index, &x1, &x2, &x3, ifname) == 21) {
        staddr[0] = (unsigned char)u0;
        staddr[1] = (unsigned char)u1;
        staddr[2] = (unsigned char)u2;
        staddr[3] = (unsigned char)u3;
        staddr[4] = (unsigned char)u4;
        staddr[5] = (unsigned char)u5;
        staddr[6] = (unsigned char)u6;
        staddr[7] = (unsigned char)u7;
        staddr[8] = (unsigned char)u8;
        staddr[9] = (unsigned char)u9;
        staddr[10] = (unsigned char)ua;
        staddr[11] = (unsigned char)ub;
        staddr[12] = (unsigned char)uc;
        staddr[13] = (unsigned char)ud;
        staddr[14] = (unsigned char)ue;
        staddr[15] = (unsigned char)uf;
        nifs ++;
        if (nifs > localifsSize) {
            localifs = (struct localinterface *) realloc (
                        localifs, sizeof (struct localinterface)* (localifsSize+5));
            if (localifs == 0) {
                nifs = 0;
                fclose (f);
                return;
            }
            lif = localifs + localifsSize;
            localifsSize += 5;
        } else {
            lif ++;
        }
        memcpy (lif->localaddr, staddr, 16);
        lif->index = index;
    }
    fclose (f);
}

/* return the scope_id (interface index) of the
 * interface corresponding to the given address
 * returns 0 if no match found
 */

static int getLocalScopeID (char *addr) {
    struct localinterface *lif;
    int i;
    if (localifs == 0) {
        initLocalIfs();
    }
    for (i=0, lif=localifs; i<nifs; i++, lif++) {
        if (memcmp (addr, lif->localaddr, 16) == 0) {
            return lif->index;
        }
    }
    return 0;
}

void initLocalAddrTable () {
    initLoopbackRoutes();
    initLocalIfs();
}

#else

void initLocalAddrTable () {}

#endif

void parseExclusiveBindProperty(JNIEnv *env) {
#ifdef __solaris__
    jstring s, flagSet;
    jclass iCls;
    jmethodID mid;

    s = (*env)->NewStringUTF(env, "sun.net.useExclusiveBind");
    CHECK_NULL(s);
    iCls = (*env)->FindClass(env, "java/lang/System");
    CHECK_NULL(iCls);
    mid = (*env)->GetStaticMethodID(env, iCls, "getProperty",
                "(Ljava/lang/String;)Ljava/lang/String;");
    CHECK_NULL(mid);
    flagSet = (*env)->CallStaticObjectMethod(env, iCls, mid, s);
    if (flagSet != NULL) {
        useExclBind = 1;
    }
#endif
}

/* In the case of an IPv4 Inetaddress this method will return an
 * IPv4 mapped address where IPv6 is available and v4MappedAddress is TRUE.
 * Otherwise it will return a sockaddr_in structure for an IPv4 InetAddress.
*/
JNIEXPORT int JNICALL
NET_InetAddressToSockaddr(JNIEnv *env, jobject iaObj, int port, struct sockaddr *him,
                          int *len, jboolean v4MappedAddress) {
    jint family;
    family = getInetAddress_family(env, iaObj);
#ifdef AF_INET6
    /* needs work. 1. family 2. clean up him6 etc deallocate memory */
    if (ipv6_available() && !(family == IPv4 && v4MappedAddress == JNI_FALSE)) {
        struct sockaddr_in6 *him6 = (struct sockaddr_in6 *)him;
        jbyte caddr[16];
        jint address;


        if (family == IPv4) { /* will convert to IPv4-mapped address */
            memset((char *) caddr, 0, 16);
            address = getInetAddress_addr(env, iaObj);
            if (address == INADDR_ANY) {
                /* we would always prefer IPv6 wildcard address
                   caddr[10] = 0xff;
                   caddr[11] = 0xff; */
            } else {
                caddr[10] = 0xff;
                caddr[11] = 0xff;
                caddr[12] = ((address >> 24) & 0xff);
                caddr[13] = ((address >> 16) & 0xff);
                caddr[14] = ((address >> 8) & 0xff);
                caddr[15] = (address & 0xff);
            }
        } else {
            getInet6Address_ipaddress(env, iaObj, (char *)caddr);
        }
        memset((char *)him6, 0, sizeof(struct sockaddr_in6));
        him6->sin6_port = htons(port);
        memcpy((void *)&(him6->sin6_addr), caddr, sizeof(struct in6_addr) );
        him6->sin6_family = AF_INET6;
        *len = sizeof(struct sockaddr_in6) ;

#if defined(_ALLBSD_SOURCE) && defined(_AF_INET6)
// XXXBSD: should we do something with scope id here ? see below linux comment
/* MMM: Come back to this! */
#endif

        /*
         * On Linux if we are connecting to a link-local address
         * we need to specify the interface in the scope_id (2.4 kernel only)
         *
         * If the scope was cached the we use the cached value. If not cached but
         * specified in the Inet6Address we use that, but we first check if the
         * address needs to be routed via the loopback interface. In this case,
         * we override the specified value with that of the loopback interface.
         * If no cached value exists and no value was specified by user, then
         * we try to determine a value from the routing table. In all these
         * cases the used value is cached for further use.
         */
#ifdef __linux__
        if (IN6_IS_ADDR_LINKLOCAL(&(him6->sin6_addr))) {
            int cached_scope_id = 0, scope_id = 0;

            if (ia6_cachedscopeidID) {
                cached_scope_id = (int)(*env)->GetIntField(env, iaObj, ia6_cachedscopeidID);
                /* if cached value exists then use it. Otherwise, check
                 * if scope is set in the address.
                 */
                if (!cached_scope_id) {
                    if (ia6_scopeidID) {
                        scope_id = getInet6Address_scopeid(env, iaObj);
                    }
                    if (scope_id != 0) {
                        /* check user-specified value for loopback case
                         * that needs to be overridden
                         */
                        if (kernelIsV24() && needsLoopbackRoute (&him6->sin6_addr)) {
                            cached_scope_id = lo_scope_id;
                            (*env)->SetIntField(env, iaObj, ia6_cachedscopeidID, cached_scope_id);
                        }
                    } else {
                        /*
                         * Otherwise consult the IPv6 routing tables to
                         * try determine the appropriate interface.
                         */
                        if (kernelIsV24()) {
                            cached_scope_id = getDefaultIPv6Interface( &(him6->sin6_addr) );
                        } else {
                            cached_scope_id = getLocalScopeID( (char *)&(him6->sin6_addr) );
                            if (cached_scope_id == 0) {
                                cached_scope_id = getDefaultIPv6Interface( &(him6->sin6_addr) );
                            }
                        }
                        (*env)->SetIntField(env, iaObj, ia6_cachedscopeidID, cached_scope_id);
                    }
                }
            }

            /*
             * If we have a scope_id use the extended form
             * of sockaddr_in6.
             */

            struct sockaddr_in6 *him6 =
                    (struct sockaddr_in6 *)him;
            him6->sin6_scope_id = cached_scope_id != 0 ?
                                        cached_scope_id    : scope_id;
            *len = sizeof(struct sockaddr_in6);
        }
#else
        /* handle scope_id for solaris */

        if (family != IPv4) {
            if (ia6_scopeidID) {
                him6->sin6_scope_id = getInet6Address_scopeid(env, iaObj);
            }
        }
#endif
    } else
#endif /* AF_INET6 */
        {
            struct sockaddr_in *him4 = (struct sockaddr_in*)him;
            jint address;
            if (family == IPv6) {
              JNU_ThrowByName(env, JNU_JAVANETPKG "SocketException", "Protocol family unavailable");
              return -1;
            }
            memset((char *) him4, 0, sizeof(struct sockaddr_in));
            address = getInetAddress_addr(env, iaObj);
            him4->sin_port = htons((short) port);
            him4->sin_addr.s_addr = (uint32_t) htonl(address);
            him4->sin_family = AF_INET;
            *len = sizeof(struct sockaddr_in);
        }
    return 0;
}

void
NET_SetTrafficClass(struct sockaddr *him, int trafficClass) {
#ifdef AF_INET6
    if (him->sa_family == AF_INET6) {
        struct sockaddr_in6 *him6 = (struct sockaddr_in6 *)him;
        him6->sin6_flowinfo = htonl((trafficClass & 0xff) << 20);
    }
#endif /* AF_INET6 */
}

JNIEXPORT jint JNICALL
NET_GetPortFromSockaddr(struct sockaddr *him) {
#ifdef AF_INET6
    if (him->sa_family == AF_INET6) {
        return ntohs(((struct sockaddr_in6*)him)->sin6_port);

        } else
#endif /* AF_INET6 */
            {
                return ntohs(((struct sockaddr_in*)him)->sin_port);
            }
}

int
NET_IsIPv4Mapped(jbyte* caddr) {
    int i;
    for (i = 0; i < 10; i++) {
        if (caddr[i] != 0x00) {
            return 0; /* false */
        }
    }

    if (((caddr[10] & 0xff) == 0xff) && ((caddr[11] & 0xff) == 0xff)) {
        return 1; /* true */
    }
    return 0; /* false */
}

int
NET_IPv4MappedToIPv4(jbyte* caddr) {
    return ((caddr[12] & 0xff) << 24) | ((caddr[13] & 0xff) << 16) | ((caddr[14] & 0xff) << 8)
        | (caddr[15] & 0xff);
}

int
NET_IsEqual(jbyte* caddr1, jbyte* caddr2) {
    int i;
    for (i = 0; i < 16; i++) {
        if (caddr1[i] != caddr2[i]) {
            return 0; /* false */
        }
    }
    return 1;
}

int NET_IsZeroAddr(jbyte* caddr) {
    int i;
    for (i = 0; i < 16; i++) {
        if (caddr[i] != 0) {
            return 0;
        }
    }
    return 1;
}

/*
 * Map the Java level socket option to the platform specific
 * level and option name.
 */
int
NET_MapSocketOption(jint cmd, int *level, int *optname) {
    static struct {
        jint cmd;
        int level;
        int optname;
    } const opts[] = {
        { java_net_SocketOptions_TCP_NODELAY,           IPPROTO_TCP,    TCP_NODELAY },
        { java_net_SocketOptions_SO_OOBINLINE,          SOL_SOCKET,     SO_OOBINLINE },
        { java_net_SocketOptions_SO_LINGER,             SOL_SOCKET,     SO_LINGER },
        { java_net_SocketOptions_SO_SNDBUF,             SOL_SOCKET,     SO_SNDBUF },
        { java_net_SocketOptions_SO_RCVBUF,             SOL_SOCKET,     SO_RCVBUF },
        { java_net_SocketOptions_SO_KEEPALIVE,          SOL_SOCKET,     SO_KEEPALIVE },
        { java_net_SocketOptions_SO_REUSEADDR,          SOL_SOCKET,     SO_REUSEADDR },
        { java_net_SocketOptions_SO_BROADCAST,          SOL_SOCKET,     SO_BROADCAST },
        { java_net_SocketOptions_IP_TOS,                IPPROTO_IP,     IP_TOS },
        { java_net_SocketOptions_IP_MULTICAST_IF,       IPPROTO_IP,     IP_MULTICAST_IF },
        { java_net_SocketOptions_IP_MULTICAST_IF2,      IPPROTO_IP,     IP_MULTICAST_IF },
        { java_net_SocketOptions_IP_MULTICAST_LOOP,     IPPROTO_IP,     IP_MULTICAST_LOOP },
    };

    int i;

    /*
     * Different multicast options if IPv6 is enabled
     */
#ifdef AF_INET6
    if (ipv6_available()) {
        switch (cmd) {
            case java_net_SocketOptions_IP_MULTICAST_IF:
            case java_net_SocketOptions_IP_MULTICAST_IF2:
                *level = IPPROTO_IPV6;
                *optname = IPV6_MULTICAST_IF;
                return 0;

            case java_net_SocketOptions_IP_MULTICAST_LOOP:
                *level = IPPROTO_IPV6;
                *optname = IPV6_MULTICAST_LOOP;
                return 0;
        }
    }
#endif

    /*
     * Map the Java level option to the native level
     */
    for (i=0; i<(int)(sizeof(opts) / sizeof(opts[0])); i++) {
        if (cmd == opts[i].cmd) {
            *level = opts[i].level;
            *optname = opts[i].optname;
            return 0;
        }
    }

    /* not found */
    return -1;
}

/*
 * Determine the default interface for an IPv6 address.
 *
 * 1. Scans /proc/net/ipv6_route for a matching route
 *    (eg: fe80::/10 or a route for the specific address).
 *    This will tell us the interface to use (eg: "eth0").
 *
 * 2. Lookup /proc/net/if_inet6 to map the interface
 *    name to an interface index.
 *
 * Returns :-
 *      -1 if error
 *       0 if no matching interface
 *      >1 interface index to use for the link-local address.
 */
#if defined(__linux__) && defined(AF_INET6)
int getDefaultIPv6Interface(struct in6_addr *target_addr) {
    FILE *f;
    char srcp[8][5];
    char hopp[8][5];
    int dest_plen, src_plen, use, refcnt, metric;
    unsigned long flags;
    char dest_str[40];
    struct in6_addr dest_addr;
    char device[16];
    jboolean match = JNI_FALSE;

    /*
     * Scan /proc/net/ipv6_route looking for a matching
     * route.
     */
    if ((f = fopen("/proc/net/ipv6_route", "r")) == NULL) {
        return -1;
    }
    while (fscanf(f, "%4s%4s%4s%4s%4s%4s%4s%4s %02x "
                     "%4s%4s%4s%4s%4s%4s%4s%4s %02x "
                     "%4s%4s%4s%4s%4s%4s%4s%4s "
                     "%08x %08x %08x %08lx %8s",
                     dest_str, &dest_str[5], &dest_str[10], &dest_str[15],
                     &dest_str[20], &dest_str[25], &dest_str[30], &dest_str[35],
                     &dest_plen,
                     srcp[0], srcp[1], srcp[2], srcp[3],
                     srcp[4], srcp[5], srcp[6], srcp[7],
                     &src_plen,
                     hopp[0], hopp[1], hopp[2], hopp[3],
                     hopp[4], hopp[5], hopp[6], hopp[7],
                     &metric, &use, &refcnt, &flags, device) == 31) {

        /*
         * Some routes should be ignored
         */
        if ( (dest_plen < 0 || dest_plen > 128)  ||
             (src_plen != 0) ||
             (flags & (RTF_POLICY | RTF_FLOW)) ||
             ((flags & RTF_REJECT) && dest_plen == 0) ) {
            continue;
        }

        /*
         * Convert the destination address
         */
        dest_str[4] = ':';
        dest_str[9] = ':';
        dest_str[14] = ':';
        dest_str[19] = ':';
        dest_str[24] = ':';
        dest_str[29] = ':';
        dest_str[34] = ':';
        dest_str[39] = '\0';

        if (inet_pton(AF_INET6, dest_str, &dest_addr) < 0) {
            /* not an Ipv6 address */
            continue;
        } else {
            /*
             * The prefix len (dest_plen) indicates the number of bits we
             * need to match on.
             *
             * dest_plen / 8    => number of bytes to match
             * dest_plen % 8    => number of additional bits to match
             *
             * eg: fe80::/10 => match 1 byte + 2 additional bits in the
             *                  the next byte.
             */
            int byte_count = dest_plen >> 3;
            int extra_bits = dest_plen & 0x3;

            if (byte_count > 0) {
                if (memcmp(target_addr, &dest_addr, byte_count)) {
                    continue;  /* no match */
                }
            }

            if (extra_bits > 0) {
                unsigned char c1 = ((unsigned char *)target_addr)[byte_count];
                unsigned char c2 = ((unsigned char *)&dest_addr)[byte_count];
                unsigned char mask = 0xff << (8 - extra_bits);
                if ((c1 & mask) != (c2 & mask)) {
                    continue;
                }
            }

            /*
             * We have a match
             */
            match = JNI_TRUE;
            break;
        }
    }
    fclose(f);

    /*
     * If there's a match then we lookup the interface
     * index.
     */
    if (match) {
        char devname[21];
        char addr6p[8][5];
        int plen, scope, dad_status, if_idx;

        if ((f = fopen("/proc/net/if_inet6", "r")) != NULL) {
            while (fscanf(f, "%4s%4s%4s%4s%4s%4s%4s%4s %08x %02x %02x %02x %20s\n",
                      addr6p[0], addr6p[1], addr6p[2], addr6p[3],
                      addr6p[4], addr6p[5], addr6p[6], addr6p[7],
                  &if_idx, &plen, &scope, &dad_status, devname) == 13) {

                if (strcmp(devname, device) == 0) {
                    /*
                     * Found - so just return the index
                     */
                    fclose(f);
                    return if_idx;
                }
            }
            fclose(f);
        } else {
            /*
             * Couldn't open /proc/net/if_inet6
             */
            return -1;
        }
    }

    /*
     * If we get here it means we didn't there wasn't any
     * route or we couldn't get the index of the interface.
     */
    return 0;
}
#endif


/*
 * Wrapper for getsockopt system routine - does any necessary
 * pre/post processing to deal with OS specific oddities :-
 *
 * IP_TOS is a no-op with IPv6 sockets as it's setup when
 * the connection is established.
 *
 * On Linux the SO_SNDBUF/SO_RCVBUF values must be post-processed
 * to compensate for an incorrect value returned by the kernel.
 */
int
NET_GetSockOpt(int fd, int level, int opt, void *result,
               int *len)
{
    int rv;

#ifdef AF_INET6
    if ((level == IPPROTO_IP) && (opt == IP_TOS)) {
        if (ipv6_available()) {

            /*
             * For IPv6 socket option implemented at Java-level
             * so return -1.
             */
            int *tc = (int *)result;
            *tc = -1;
            return 0;
        }
    }
#endif

#ifdef __solaris__
    rv = getsockopt(fd, level, opt, result, len);
#else
    {
        socklen_t socklen = *len;
        rv = getsockopt(fd, level, opt, result, &socklen);
        *len = socklen;
    }
#endif

    if (rv < 0) {
        return rv;
    }

#ifdef __linux__
    /*
     * On Linux SO_SNDBUF/SO_RCVBUF aren't symmetric. This
     * stems from additional socket structures in the send
     * and receive buffers.
     */
    if ((level == SOL_SOCKET) && ((opt == SO_SNDBUF)
                                  || (opt == SO_RCVBUF))) {
        int n = *((int *)result);
        n /= 2;
        *((int *)result) = n;
    }
#endif

/* Workaround for Mac OS treating linger value as
 *  signed integer
 */
#ifdef MACOSX
    if (level == SOL_SOCKET && opt == SO_LINGER) {
        struct linger* to_cast = (struct linger*)result;
        to_cast->l_linger = (unsigned short)to_cast->l_linger;
    }
#endif
    return rv;
}

/*
 * Wrapper for setsockopt system routine - performs any
 * necessary pre/post processing to deal with OS specific
 * issue :-
 *
 * On Solaris need to limit the suggested value for SO_SNDBUF
 * and SO_RCVBUF to the kernel configured limit
 *
 * For IP_TOS socket option need to mask off bits as this
 * aren't automatically masked by the kernel and results in
 * an error. In addition IP_TOS is a NOOP with IPv6 as it
 * should be setup as connection time.
 */
int
NET_SetSockOpt(int fd, int level, int  opt, const void *arg,
               int len)
{
#ifndef IPTOS_TOS_MASK
#define IPTOS_TOS_MASK 0x1e
#endif
#ifndef IPTOS_PREC_MASK
#define IPTOS_PREC_MASK 0xe0
#endif

#if defined(_ALLBSD_SOURCE)
#if defined(KIPC_MAXSOCKBUF)
    int mib[3];
    size_t rlen;
#endif

    int *bufsize;

#ifdef __APPLE__
    static int maxsockbuf = -1;
#else
    static long maxsockbuf = -1;
#endif

    int addopt;
    struct linger *ling;
#endif

    /*
     * IPPROTO/IP_TOS :-
     * 1. IPv6 on Solaris/Mac OS: NOOP and will be set
     *    in flowinfo field when connecting TCP socket,
     *    or sending UDP packet.
     * 2. IPv6 on Linux: By default Linux ignores flowinfo
     *    field so enable IPV6_FLOWINFO_SEND so that flowinfo
     *    will be examined.
     * 3. IPv4: set socket option based on ToS and Precedence
     *    fields (otherwise get invalid argument)
     */
    if (level == IPPROTO_IP && opt == IP_TOS) {
        int *iptos;

#if defined(AF_INET6) && (defined(__solaris__) || defined(MACOSX))
        if (ipv6_available()) {
            return 0;
        }
#endif

#if defined(AF_INET6) && defined(__linux__)
        if (ipv6_available()) {
            int optval = 1;
            return setsockopt(fd, IPPROTO_IPV6, IPV6_FLOWINFO_SEND,
                              (void *)&optval, sizeof(optval));
        }
#endif

        iptos = (int *)arg;
        *iptos &= (IPTOS_TOS_MASK | IPTOS_PREC_MASK);
    }

    /*
     * SOL_SOCKET/{SO_SNDBUF,SO_RCVBUF} - On Solaris we may need to clamp
     * the value when it exceeds the system limit.
     */
#ifdef __solaris__
    if (level == SOL_SOCKET) {
        if (opt == SO_SNDBUF || opt == SO_RCVBUF) {
            int sotype=0, arglen;
            int *bufsize, maxbuf;
            int ret;

            /* Attempt with the original size */
            ret = setsockopt(fd, level, opt, arg, len);
            if ((ret == 0) || (ret == -1 && errno != ENOBUFS))
                return ret;

            /* Exceeded system limit so clamp and retry */

            arglen = sizeof(sotype);
            if (getsockopt(fd, SOL_SOCKET, SO_TYPE, (void *)&sotype,
                           &arglen) < 0) {
                return -1;
            }

            /*
             * We try to get tcp_maxbuf (and udp_max_buf) using
             * an ioctl() that isn't available on all versions of Solaris.
             * If that fails, we use the search algorithm in findMaxBuf()
             */
            if (!init_tcp_max_buf && sotype == SOCK_STREAM) {
                tcp_max_buf = net_getParam("/dev/tcp", "tcp_max_buf");
                if (tcp_max_buf == -1) {
                    tcp_max_buf = findMaxBuf(fd, opt, SOCK_STREAM);
                    if (tcp_max_buf == -1) {
                        return -1;
                    }
                }
                init_tcp_max_buf = 1;
            } else if (!init_udp_max_buf && sotype == SOCK_DGRAM) {
                udp_max_buf = net_getParam("/dev/udp", "udp_max_buf");
                if (udp_max_buf == -1) {
                    udp_max_buf = findMaxBuf(fd, opt, SOCK_DGRAM);
                    if (udp_max_buf == -1) {
                        return -1;
                    }
                }
                init_udp_max_buf = 1;
            }

            maxbuf = (sotype == SOCK_STREAM) ? tcp_max_buf : udp_max_buf;
            bufsize = (int *)arg;
            if (*bufsize > maxbuf) {
                *bufsize = maxbuf;
            }
        }
    }
#endif

    /*
     * On Linux the receive buffer is used for both socket
     * structures and the the packet payload. The implication
     * is that if SO_RCVBUF is too small then small packets
     * must be discard.
     */
#ifdef __linux__
    if (level == SOL_SOCKET && opt == SO_RCVBUF) {
        int *bufsize = (int *)arg;
        if (*bufsize < 1024) {
            *bufsize = 1024;
        }
    }
#endif

#if defined(_ALLBSD_SOURCE)
    /*
     * SOL_SOCKET/{SO_SNDBUF,SO_RCVBUF} - On FreeBSD need to
     * ensure that value is <= kern.ipc.maxsockbuf as otherwise we get
     * an ENOBUFS error.
     */
    if (level == SOL_SOCKET) {
        if (opt == SO_SNDBUF || opt == SO_RCVBUF) {
#ifdef KIPC_MAXSOCKBUF
            if (maxsockbuf == -1) {
               mib[0] = CTL_KERN;
               mib[1] = KERN_IPC;
               mib[2] = KIPC_MAXSOCKBUF;
               rlen = sizeof(maxsockbuf);
               if (sysctl(mib, 3, &maxsockbuf, &rlen, NULL, 0) == -1)
                   maxsockbuf = 1024;

#if 1
               /* XXXBSD: This is a hack to workaround mb_max/mb_max_adj
                  problem.  It should be removed when kern.ipc.maxsockbuf
                  will be real value. */
               maxsockbuf = (maxsockbuf/5)*4;
#endif
           }
#elif defined(__OpenBSD__)
           maxsockbuf = SB_MAX;
#else
           maxsockbuf = 64 * 1024;      /* XXX: NetBSD */
#endif

           bufsize = (int *)arg;
           if (*bufsize > maxsockbuf) {
               *bufsize = maxsockbuf;
           }

           if (opt == SO_RCVBUF && *bufsize < 1024) {
                *bufsize = 1024;
           }

        }
    }

    /*
     * On Solaris, SO_REUSEADDR will allow multiple datagram
     * sockets to bind to the same port.  The network jck tests
     * for this "feature", so we need to emulate it by turning on
     * SO_REUSEPORT as well for that combination.
     */
    if (level == SOL_SOCKET && opt == SO_REUSEADDR) {
        int sotype;
        socklen_t arglen;

        arglen = sizeof(sotype);
        if (getsockopt(fd, SOL_SOCKET, SO_TYPE, (void *)&sotype, &arglen) < 0) {
            return -1;
        }

        if (sotype == SOCK_DGRAM) {
            addopt = SO_REUSEPORT;
            setsockopt(fd, level, addopt, arg, len);
        }
    }

#endif

    return setsockopt(fd, level, opt, arg, len);
}

/*
 * Wrapper for bind system call - performs any necessary pre/post
 * processing to deal with OS specific issues :-
 *
 * Linux allows a socket to bind to 127.0.0.255 which must be
 * caught.
 *
 * On Solaris with IPv6 enabled we must use an exclusive
 * bind to guarantee a unique port number across the IPv4 and
 * IPv6 port spaces.
 *
 */
int
NET_Bind(int fd, struct sockaddr *him, int len)
{
#if defined(__solaris__) && defined(AF_INET6)
    int level = -1;
    int exclbind = -1;
#endif
    int rv;

#ifdef __linux__
    /*
     * ## get bugId for this issue - goes back to 1.2.2 port ##
     * ## When IPv6 is enabled this will be an IPv4-mapped
     * ## with family set to AF_INET6
     */
    if (him->sa_family == AF_INET) {
        struct sockaddr_in *sa = (struct sockaddr_in *)him;
        if ((ntohl(sa->sin_addr.s_addr) & 0x7f0000ff) == 0x7f0000ff) {
            errno = EADDRNOTAVAIL;
            return -1;
        }
    }
#endif

#if defined(__solaris__) && defined(AF_INET6)
    /*
     * Solaris has separate IPv4 and IPv6 port spaces so we
     * use an exclusive bind when SO_REUSEADDR is not used to
     * give the illusion of a unified port space.
     * This also avoids problems with IPv6 sockets connecting
     * to IPv4 mapped addresses whereby the socket conversion
     * results in a late bind that fails because the
     * corresponding IPv4 port is in use.
     */
    if (ipv6_available()) {
        int arg, len;

        len = sizeof(arg);
        if (useExclBind || getsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
                       (char *)&arg, &len) == 0) {
            if (useExclBind || arg == 0) {
                /*
                 * SO_REUSEADDR is disabled or sun.net.useExclusiveBind
                 * property is true so enable TCP_EXCLBIND or
                 * UDP_EXCLBIND
                 */
                len = sizeof(arg);
                if (getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&arg,
                               &len) == 0) {
                    if (arg == SOCK_STREAM) {
                        level = IPPROTO_TCP;
                        exclbind = TCP_EXCLBIND;
                    } else {
                        level = IPPROTO_UDP;
                        exclbind = UDP_EXCLBIND;
                    }
                }

                arg = 1;
                setsockopt(fd, level, exclbind, (char *)&arg,
                           sizeof(arg));
            }
        }
    }

#endif

    rv = bind(fd, him, len);

#if defined(__solaris__) && defined(AF_INET6)
    if (rv < 0) {
        int en = errno;
        /* Restore *_EXCLBIND if the bind fails */
        if (exclbind != -1) {
            int arg = 0;
            setsockopt(fd, level, exclbind, (char *)&arg,
                       sizeof(arg));
        }
        errno = en;
    }
#endif

    return rv;
}

/**
 * Wrapper for select/poll with timeout on a single file descriptor.
 *
 * flags (defined in net_util_md.h can be any combination of
 * NET_WAIT_READ, NET_WAIT_WRITE & NET_WAIT_CONNECT.
 *
 * The function will return when either the socket is ready for one
 * of the specified operation or the timeout expired.
 *
 * It returns the time left from the timeout (possibly 0), or -1 if it expired.
 */

jint
NET_Wait(JNIEnv *env, jint fd, jint flags, jint timeout)
{
    jlong prevTime = JVM_CurrentTimeMillis(env, 0);
    jint read_rv;

    while (1) {
        jlong newTime;
#ifndef USE_SELECT
        {
          struct pollfd pfd;
          pfd.fd = fd;
          pfd.events = 0;
          if (flags & NET_WAIT_READ)
            pfd.events |= POLLIN;
          if (flags & NET_WAIT_WRITE)
            pfd.events |= POLLOUT;
          if (flags & NET_WAIT_CONNECT)
            pfd.events |= POLLOUT;

          errno = 0;
          read_rv = NET_Poll(&pfd, 1, timeout);
        }
#else
        {
          fd_set rd, wr, ex;
          struct timeval t;

          t.tv_sec = timeout / 1000;
          t.tv_usec = (timeout % 1000) * 1000;

          FD_ZERO(&rd);
          FD_ZERO(&wr);
          FD_ZERO(&ex);
          if (flags & NET_WAIT_READ) {
            FD_SET(fd, &rd);
          }
          if (flags & NET_WAIT_WRITE) {
            FD_SET(fd, &wr);
          }
          if (flags & NET_WAIT_CONNECT) {
            FD_SET(fd, &wr);
            FD_SET(fd, &ex);
          }

          errno = 0;
          read_rv = NET_Select(fd+1, &rd, &wr, &ex, &t);
        }
#endif

        newTime = JVM_CurrentTimeMillis(env, 0);
        timeout -= (newTime - prevTime);
        if (timeout <= 0) {
          return read_rv > 0 ? 0 : -1;
        }
        newTime = prevTime;

        if (read_rv > 0) {
          break;
        }


      } /* while */

    return timeout;
}

Other Java examples (source code examples)

Here is a short list of links related to this Java net_util_md.c source code file:

... this post is sponsored by my books ...

#1 New Release!

FP Best Seller

 

new blog posts

 

Copyright 1998-2024 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.