#define PERL_NO_GET_CONTEXT
#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"
#include <stddef.h>
#ifdef I_SYS_TYPES
#  include <sys/types.h>
#endif
#if !defined(ultrix) /* Avoid double definition. */
#  include <sys/socket.h>
#endif
#if defined(USE_SOCKS) && defined(I_SOCKS)
#  include <socks.h>
#endif
#ifdef MPE
#  define PF_INET AF_INET
#  define PF_UNIX AF_UNIX
#  define SOCK_RAW 3
#endif
#ifdef I_SYS_UN
#  include <sys/un.h>
#endif
/* XXX Configure test for <netinet/in_systm.h needed XXX */
#if defined(NeXT) || defined(__NeXT__)
#  include <netinet/in_systm.h>
#endif
#if defined(__sgi) && !defined(AF_LINK) && defined(PF_LINK) && PF_LINK == AF_LNK
#  undef PF_LINK
#endif
#if defined(I_NETINET_IN) || defined(__ultrix__)
#  include <netinet/in.h>
#endif
#if defined(I_NETINET_IP)
#  include <netinet/ip.h>
#endif
#ifdef I_NETDB
#  if !defined(ultrix)  /* Avoid double definition. */
#    include <netdb.h>
#  endif
#endif
#ifdef I_ARPA_INET
#  include <arpa/inet.h>
#endif
#ifdef I_NETINET_TCP
#  include <netinet/tcp.h>
#endif
#if defined(WIN32) && !defined(UNDER_CE)
#  include <ws2tcpip.h>
#endif
#ifdef WIN32
/* VC 6 with its original headers doesn't know about sockaddr_storage, VC 2003 does*/
#ifndef _SS_MAXSIZE
#  define _SS_MAXSIZE 128
#  define _SS_ALIGNSIZE (sizeof(__int64))
#  define _SS_PAD1SIZE (_SS_ALIGNSIZE - sizeof (short))
#  define _SS_PAD2SIZE (_SS_MAXSIZE - (sizeof (short) + _SS_PAD1SIZE \
                                                      + _SS_ALIGNSIZE))
struct sockaddr_storage {
    short ss_family;
    char __ss_pad1[_SS_PAD1SIZE];
    __int64 __ss_align;
    char __ss_pad2[_SS_PAD2SIZE];
};
typedef int socklen_t;
#define in6_addr in_addr6
#define INET_ADDRSTRLEN  22
#define INET6_ADDRSTRLEN 65
#endif
/*
 *  Under Windows, sockaddr_un is defined in afunix.h. Unfortunately
 *  MinGW and SDKs older than 10.0.17063.0 don't have it, so we have to
 *  define it here. Don't worry, it's portable. Windows has ironclad ABI
 *  stability guarantees which means that the definitions will *never*
 *  change.
 */
#ifndef UNIX_PATH_MAX
#define UNIX_PATH_MAX 108
struct sockaddr_un
{
    USHORT sun_family;
    char sun_path[UNIX_PATH_MAX];
};
#endif
/*
 * The Windows implementations of inet_ntop and inet_pton are available
 * whenever (and only when) InetNtopA is defined.
 * Use those implementations whenever they are available.
 * Else use the implementations provided below.
*/
#ifndef InetNtopA
static int inet_pton(int af, const char *src, void *dst)
{
    struct sockaddr_storage ss;
    int size = sizeof(ss);
    ss.ss_family = af; /* per MSDN */
    if (WSAStringToAddress((char*)src, af, NULL, (struct sockaddr *)&ss, &size) != 0)
        return 0;
    switch(af) {
        case AF_INET:
            *(struct in_addr *)dst = ((struct sockaddr_in *)&ss)->sin_addr;
            return 1;
        case AF_INET6:
            *(struct in6_addr *)dst = ((struct sockaddr_in6 *)&ss)->sin6_addr;
            return 1;
        default:
            WSASetLastError(WSAEAFNOSUPPORT);
            return -1;
    }
}
static const char *inet_ntop(int af, const void *src, char *dst, socklen_t size)
{
    struct sockaddr_storage ss;
    unsigned long s = size;
    ZeroMemory(&ss, sizeof(ss));
    ss.ss_family = af;
    switch(af) {
        case AF_INET:
            ((struct sockaddr_in *)&ss)->sin_addr = *(struct in_addr *)src;
            break;
        case AF_INET6:
            ((struct sockaddr_in6 *)&ss)->sin6_addr = *(struct in6_addr *)src;
            break;
        default:
            return NULL;
    }
    /* cannot directly use &size because of strict aliasing rules */
    if (WSAAddressToString((struct sockaddr *)&ss, sizeof(ss), NULL, dst, &s) != 0)
        return NULL;
    else
        return dst;
}
#endif /* InetNtopA  not defined */
#define HAS_INETPTON
#define HAS_INETNTOP
#endif
#ifdef NETWARE
NETDB_DEFINE_CONTEXT
NETINET_DEFINE_CONTEXT
#endif
#ifdef I_SYSUIO
#  include <sys/uio.h>
#endif
#ifndef AF_NBS
#  undef PF_NBS
#endif
#ifndef AF_X25
#  undef PF_X25
#endif
#ifndef INADDR_NONE
#  define INADDR_NONE    0xffffffff
#endif /* INADDR_NONE */
#ifndef INADDR_BROADCAST
#  define INADDR_BROADCAST       0xffffffff
#endif /* INADDR_BROADCAST */
#ifndef INADDR_LOOPBACK
#  define INADDR_LOOPBACK         0x7F000001
#endif /* INADDR_LOOPBACK */
#ifndef INET_ADDRSTRLEN
#  define INET_ADDRSTRLEN 16
#endif
#ifndef C_ARRAY_LENGTH
#  define C_ARRAY_LENGTH(arr) (sizeof(arr) / sizeof(*(arr)))
#endif /* !C_ARRAY_LENGTH */
#ifndef PERL_UNUSED_VAR
#  define PERL_UNUSED_VAR(x) ((void)x)
#endif /* !PERL_UNUSED_VAR */
#ifndef PERL_UNUSED_ARG
#  define PERL_UNUSED_ARG(x) PERL_UNUSED_VAR(x)
#endif /* !PERL_UNUSED_ARG */
#ifndef Newx
#  define Newx(v,n,t) New(0,v,n,t)
#endif /* !Newx */
#ifndef SvPVx_nolen
#if defined(__GNUC__) && !defined(PERL_GCC_BRACE_GROUPS_FORBIDDEN)
#   define SvPVx_nolen(sv) ({SV *_sv = (sv); SvPV_nolen(_sv); })
#else /* __GNUC__ */
#   define SvPVx_nolen(sv) ((PL_Sv = (sv)), SvPV_nolen(PL_Sv))
#endif /* __GNU__ */
#endif /* !SvPVx_nolen */
#ifndef croak_sv
#  define croak_sv(sv)   croak("%s", SvPVx_nolen(sv))
#endif
#ifndef hv_stores
#  define hv_stores(hv, keystr, val) \
        hv_store(hv, ""keystr"", sizeof(keystr)-1, val, 0)
#endif /* !hv_stores */
#ifndef newSVpvn_flags
#  define newSVpvn_flags(s,len,flags) my_newSVpvn_flags(aTHX_ s,len,flags)
static SV *my_newSVpvn_flags(pTHX_ const char *s, STRLEN len, U32 flags)
{
    SV *sv = newSVpvn(s, len);
    SvFLAGS(sv) |= (flags & SVf_UTF8);
    return (flags & SVs_TEMP) ? sv_2mortal(sv) : sv;
}
#endif /* !newSVpvn_flags */
#ifndef SvPVbyte_nomg
#  define SvPVbyte_nomg SvPV
#endif /* !SvPVbyte_nomg */
#ifndef HEK_FLAGS
#  define HEK_FLAGS(hek) 0
#  define HVhek_UTF8 1
#endif /* !HEK_FLAGS */
#ifndef hv_common
/* These magic numbers are arbitrarily chosen (copied from perl core in fact)
 * and only have to match between this definition and the code that uses them
 */
#  define HV_FETCH_ISSTORE 0x04
#  define HV_FETCH_LVALUE  0x10
#  define hv_common(hv, keysv, key, klen, flags, act, val, hash) \
        my_hv_common(aTHX_ hv, keysv, key, klen, flags, act, val, hash)
static void *my_hv_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
        int flags, int act, SV *val, U32 hash)
{
    /*
     * This only handles the usage actually made by the code
     * generated by ExtUtils::Constant.  EU:C really ought to arrange
     * portability of its generated code itself.
     */
    if (!keysv) {
        keysv = sv_2mortal(newSVpvn(key, klen));
        if (flags & HVhek_UTF8)
            SvUTF8_on(keysv);
    }
    if (act == HV_FETCH_LVALUE) {
        return (void*)hv_fetch_ent(hv, keysv, 1, hash);
    } else if (act == HV_FETCH_ISSTORE) {
        return (void*)hv_store_ent(hv, keysv, val, hash);
    } else {
        croak("panic: my_hv_common: act=0x%x", act);
    }
}
#endif /* !hv_common */
#ifndef hv_common_key_len
#  define hv_common_key_len(hv, key, kl, act, val, hash) \
        my_hv_common_key_len(aTHX_ hv, key, kl, act, val, hash)
static void *my_hv_common_key_len(pTHX_ HV *hv, const char *key, I32 kl,
        int act, SV *val, U32 hash)
{
    STRLEN klen;
    int flags;
    if (kl < 0) {
        klen = -kl;
        flags = HVhek_UTF8;
    } else {
        klen = kl;
        flags = 0;
    }
    return hv_common(hv, NULL, key, klen, flags, act, val, hash);
}
#endif /* !hv_common_key_len */
#ifndef mPUSHi
#  define mPUSHi(i) sv_setiv_mg(PUSHs(sv_newmortal()), (IV)(i))
#endif /* !mPUSHi */
#ifndef mPUSHp
#  define mPUSHp(p,l) sv_setpvn_mg(PUSHs(sv_newmortal()), (p), (l))
#endif /* !mPUSHp */
#ifndef mPUSHs
#  define mPUSHs(s) PUSHs(sv_2mortal(s))
#endif /* !mPUSHs */
#ifndef G_LIST
#  define G_LIST G_ARRAY
#endif /* !G_LIST */
#ifndef CvCONST_on
#  undef newCONSTSUB
#  define newCONSTSUB(stash, name, val) my_newCONSTSUB(aTHX_ stash, name, val)
static CV *my_newCONSTSUB(pTHX_ HV *stash, char *name, SV *val)
{
    /*
     * This has to satisfy code generated by ExtUtils::Constant.
     * It depends on the 5.8+ layout of constant subs.  It has
     * two calls to newCONSTSUB(): one for real constants, and one
     * for undefined constants.  In the latter case, it turns the
     * initially-generated constant subs into something else, and
     * it needs the return value from newCONSTSUB() which Perl 5.6
     * doesn't provide.
     */
    GV *gv;
    CV *cv;
    Perl_newCONSTSUB(aTHX_ stash, name, val);
    ENTER;
    SAVESPTR(PL_curstash);
    PL_curstash = stash;
    gv = gv_fetchpv(name, 0, SVt_PVCV);
    cv = GvCV(gv);
    LEAVE;
    CvXSUBANY(cv).any_ptr = &PL_sv_undef;
    return cv;
}
#  define CvCONST_off(cv) my_CvCONST_off(aTHX_ cv)
static void my_CvCONST_off(pTHX_ CV *cv)
{
    op_free(CvROOT(cv));
    CvROOT(cv) = NULL;
    CvSTART(cv) = NULL;
}
#endif /* !CvCONST_on */
#ifndef HAS_INET_ATON
/*
 * Check whether "cp" is a valid ascii representation
 * of an Internet address and convert to a binary address.
 * Returns 1 if the address is valid, 0 if not.
 * This replaces inet_addr, the return value from which
 * cannot distinguish between failure and a local broadcast address.
 */
static int
my_inet_aton(const char *cp, struct in_addr *addr)
{
    dTHX;
    U32 val;
    int base;
    char c;
    int nparts;
    const char *s;
    unsigned int parts[4];
    unsigned int *pp = parts;
    if (!cp || !*cp)
        return 0;
    for (;;) {
        /*
         * Collect number up to ".".
         * Values are specified as for C:
         * 0x=hex, 0=octal, other=decimal.
         */
        val = 0; base = 10;
        if (*cp == '0') {
            if (*++cp == 'x' || *cp == 'X')
                base = 16, cp++;
            else
                base = 8;
        }
        while ((c = *cp) != '\0') {
            if (isDIGIT(c)) {
                val = (val * base) + (c - '0');
                cp++;
                continue;
            }
            if (base == 16 && (s=strchr(PL_hexdigit,c))) {
                val = (val << 4) +
                    ((s - PL_hexdigit) & 15);
                cp++;
                continue;
            }
            break;
        }
        if (*cp == '.') {
            /*
             * Internet format:
             *      a.b.c.d
             *      a.b.c   (with c treated as 16-bits)
             *      a.b     (with b treated as 24 bits)
             */
            if (pp >= parts + 3 || val > 0xff)
                return 0;
            *pp++ = val, cp++;
        } else
            break;
    }
    /*
     * Check for trailing characters.
     */
    if (*cp && !isSPACE(*cp))
        return 0;
    /*
     * Concoct the address according to
     * the number of parts specified.
     */
    nparts = pp - parts + 1;        /* force to an int for switch() */
    switch (nparts) {
        case 1:                         /* a -- 32 bits */
            break;
        case 2:                         /* a.b -- 8.24 bits */
            if (val > 0xffffff)
                return 0;
            val |= parts[0] << 24;
            break;
        case 3:                         /* a.b.c -- 8.8.16 bits */
            if (val > 0xffff)
                return 0;
            val |= (parts[0] << 24) | (parts[1] << 16);
            break;
        case 4:                         /* a.b.c.d -- 8.8.8.8 bits */
            if (val > 0xff)
                return 0;
            val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
            break;
    }
    addr->s_addr = htonl(val);
    return 1;
}
#undef inet_aton
#define inet_aton my_inet_aton
#endif /* ! HAS_INET_ATON */
/* These are not gni() constants; they're extensions for the perl API */
/* The definitions in Socket.pm and Socket.xs must match */
#define NIx_NOHOST   (1 << 0)
#define NIx_NOSERV   (1 << 1)
/* On Windows, ole2.h defines a macro called "interface". We don't need that,
 * and it will complicate the variables in pack_ip_mreq() etc. (RT87389)
 */
#undef interface
/* STRUCT_OFFSET should have come from from perl.h, but if not,
 * roll our own (not using offsetof() since that is C99). */
#ifndef STRUCT_OFFSET
#  define STRUCT_OFFSET(s,m)  (Size_t)(&(((s *)0)->m))
#endif
static SV *
not_here(const char *s)
{
    croak("Socket::%s not implemented on this architecture", s);
    return NULL;
}
#define PERL_IN_ADDR_S_ADDR_SIZE 4
/*
* Bad assumptions possible here.
*
* Bad Assumption 1: struct in_addr has no other fields
* than the s_addr (which is the field we care about
* in here, really). However, we can be fed either 4-byte
* addresses (from pack("N", ...), or va.b.c.d, or ...),
* or full struct in_addrs (from e.g. pack_sockaddr_in()),
* which may or may not be 4 bytes in size.
*
* Bad Assumption 2: the s_addr field is a simple type
* (such as an int, u_int32_t).  It can be a bit field,
* in which case using & (address-of) on it or taking sizeof()
* wouldn't go over too well.  (Those are not attempted
* now but in case someone thinks to change the below code
* to use addr.s_addr instead of addr, you have been warned.)
*
* Bad Assumption 3: the s_addr is the first field in
* an in_addr, or that its bytes are the first bytes in
* an in_addr.
*
* These bad assumptions are wrong in UNICOS which has
* struct in_addr { struct { u_long  st_addr:32; } s_da };
* #define s_addr s_da.st_addr
* and u_long is 64 bits.
*
* --jhi */
#include "const-c.inc"
#if defined(HAS_GETADDRINFO) && !defined(HAS_GAI_STRERROR)
static const char *gai_strerror(int err)
{
    switch (err)
    {
#ifdef EAI_ADDRFAMILY
        case EAI_ADDRFAMILY:
            return "Address family for hostname is not supported.";
#endif
#ifdef EAI_AGAIN
        case EAI_AGAIN:
            return "The name could not be resolved at this time.";
#endif
#ifdef EAI_BADFLAGS
        case EAI_BADFLAGS:
            return "The flags parameter has an invalid value.";
#endif
#ifdef EAI_FAIL
        case EAI_FAIL:
            return "A non-recoverable error occurred while resolving the name.";
#endif
#ifdef EAI_FAMILY
        case EAI_FAMILY:
            return "The address family was not recognized or length is invalid.";
#endif
#ifdef EAI_MEMORY
        case EAI_MEMORY:
            return "A memory allocation failure occurred.";
#endif
#ifdef EAI_NODATA
        case EAI_NODATA:
            return "No address is associated with the hostname.";
#endif
#ifdef EAI_NONAME
        case EAI_NONAME:
            return "The name does not resolve for the supplied parameters.";
#endif
#ifdef EAI_OVERFLOW
        case EAI_OVERFLOW:
            return "An argument buffer overflowed.";
#endif
#ifdef EAI_SERVICE
        case EAI_SERVICE:
            return "The service parameter was not recognized for the specified socket type.";
#endif
#ifdef EAI_SOCKTYPE
        case EAI_SOCKTYPE:
            return "The specified socket type was not recognized.";
#endif
#ifdef EAI_SYSTEM
        case EAI_SYSTEM:
            return "A system error occurred - see errno.";
#endif
        default:
            return "Unknown error in getaddrinfo().";
    }
}
#endif
#ifdef HAS_GETADDRINFO
static SV *err_to_SV(pTHX_ int err)
{
    SV *ret = sv_newmortal();
    (void) SvUPGRADE(ret, SVt_PVNV);
    if(err) {
        const char *error = gai_strerror(err);
        sv_setpv(ret, error);
    }
    else {
        sv_setpv(ret, "");
    }
    SvIV_set(ret, err); SvIOK_on(ret);
    return ret;
}
static void xs_getaddrinfo(pTHX_ CV *cv)
{
    dXSARGS;
    SV   *host;
    SV   *service;
    SV   *hints;
    char *hostname = NULL;
    char *servicename = NULL;
    STRLEN len;
    struct addrinfo hints_s;
    struct addrinfo *res;
    struct addrinfo *res_iter;
    int err;
    int n_res;
    PERL_UNUSED_ARG(cv);
    if(items > 3)
        croak("Usage: Socket::getaddrinfo(host, service, hints)");
    SP -= items;
    if(items < 1)
        host = &PL_sv_undef;
    else
        host = ST(0);
    if(items < 2)
        service = &PL_sv_undef;
    else
        service = ST(1);
    if(items < 3)
        hints = NULL;
    else
        hints = ST(2);
    SvGETMAGIC(host);
    if(SvOK(host)) {
        hostname = SvPVbyte_nomg(host, len);
        if (!len)
            hostname = NULL;
    }
    SvGETMAGIC(service);
    if(SvOK(service)) {
        servicename = SvPVbyte_nomg(service, len);
        if (!len)
            servicename = NULL;
    }
    Zero(&hints_s, sizeof(hints_s), char);
    hints_s.ai_family = PF_UNSPEC;
    if(hints && SvOK(hints)) {
        HV *hintshash;
        SV **valp;
        if(!SvROK(hints) || SvTYPE(SvRV(hints)) != SVt_PVHV)
            croak("hints is not a HASH reference");
        hintshash = (HV*)SvRV(hints);
        if((valp = hv_fetch(hintshash, "flags", 5, 0)) != NULL && SvOK(*valp))
            hints_s.ai_flags = SvIV(*valp);
        if((valp = hv_fetch(hintshash, "family", 6, 0)) != NULL && SvOK(*valp))
            hints_s.ai_family = SvIV(*valp);
        if((valp = hv_fetch(hintshash, "socktype", 8, 0)) != NULL && SvOK(*valp))
            hints_s.ai_socktype = SvIV(*valp);
        if((valp = hv_fetch(hintshash, "protocol", 8, 0)) != NULL && SvOK(*valp))
            hints_s.ai_protocol = SvIV(*valp);
    }
    err = getaddrinfo(hostname, servicename, &hints_s, &res);
    XPUSHs(err_to_SV(aTHX_ err));
    if(err)
        XSRETURN(1);
    n_res = 0;
    for(res_iter = res; res_iter; res_iter = res_iter->ai_next) {
        HV *res_hv = newHV();
        (void)hv_stores(res_hv, "family",   newSViv(res_iter->ai_family));
        (void)hv_stores(res_hv, "socktype", newSViv(res_iter->ai_socktype));
        (void)hv_stores(res_hv, "protocol", newSViv(res_iter->ai_protocol));
        (void)hv_stores(res_hv, "addr",     newSVpvn((char*)res_iter->ai_addr, res_iter->ai_addrlen));
        if(res_iter->ai_canonname)
            (void)hv_stores(res_hv, "canonname", newSVpv(res_iter->ai_canonname, 0));
        else
            (void)hv_stores(res_hv, "canonname", newSV(0));
        XPUSHs(sv_2mortal(newRV_noinc((SV*)res_hv)));
        n_res++;
    }
    freeaddrinfo(res);
    XSRETURN(1 + n_res);
}
#endif
#ifdef HAS_GETNAMEINFO
static void xs_getnameinfo(pTHX_ CV *cv)
{
    dXSARGS;
    SV  *addr;
    int  flags;
    int  xflags;
    char host[1024];
    char serv[256];
    char *sa; /* we'll cast to struct sockaddr * when necessary */
    STRLEN addr_len;
    int err;
    int want_host, want_serv;
    PERL_UNUSED_ARG(cv);
    if(items < 1 || items > 3)
        croak("Usage: Socket::getnameinfo(addr, flags=0, xflags=0)");
    SP -= items;
    addr = ST(0);
    SvGETMAGIC(addr);
    if(items < 2)
        flags = 0;
    else
        flags = SvIV(ST(1));
    if(items < 3)
        xflags = 0;
    else
        xflags = SvIV(ST(2));
    want_host = !(xflags & NIx_NOHOST);
    want_serv = !(xflags & NIx_NOSERV);
    if(!SvPOKp(addr))
        croak("addr is not a string");
    addr_len = SvCUR(addr);
    /* We need to ensure the sockaddr is aligned, because a random SvPV might
     * not be due to SvOOK */
    Newx(sa, addr_len, char);
    Copy(SvPV_nolen(addr), sa, addr_len, char);
#ifdef HAS_SOCKADDR_SA_LEN
    ((struct sockaddr *)sa)->sa_len = addr_len;
#endif
    err = getnameinfo((struct sockaddr *)sa, addr_len,
#ifdef OS390    /* This OS requires both parameters to be non-NULL */
            host, sizeof(host),
            serv, sizeof(serv),
#else
            want_host ? host : NULL, want_host ? sizeof(host) : 0,
            want_serv ? serv : NULL, want_serv ? sizeof(serv) : 0,
#endif
            flags);
    Safefree(sa);
    XPUSHs(err_to_SV(aTHX_ err));
    if(err)
        XSRETURN(1);
    XPUSHs(want_host ? sv_2mortal(newSVpv(host, 0)) : &PL_sv_undef);
    XPUSHs(want_serv ? sv_2mortal(newSVpv(serv, 0)) : &PL_sv_undef);
    XSRETURN(3);
}
#endif
MODULE = Socket         PACKAGE = Socket
INCLUDE: const-xs.inc
BOOT:
#ifdef HAS_GETADDRINFO
        newXS("Socket::getaddrinfo", xs_getaddrinfo, __FILE__);
#endif
#ifdef HAS_GETNAMEINFO
        newXS("Socket::getnameinfo", xs_getnameinfo, __FILE__);
#endif
void
inet_aton(host)
    char *  host
    CODE:
    {
#ifdef HAS_GETADDRINFO
        struct addrinfo *res;
        struct addrinfo hints = {0};
        hints.ai_family = AF_INET;
        if (!getaddrinfo(host, NULL, &hints, &res)) {
            ST(0) = sv_2mortal(newSVpvn(
                        (char *)&(((struct sockaddr_in *)res->ai_addr)->sin_addr.s_addr),
                        4));
            freeaddrinfo(res);
            XSRETURN(1);
        }
#else
        struct in_addr ip_address;
        struct hostent * phe;
        if ((*host != '\0') && inet_aton(host, &ip_address)) {
            ST(0) = sv_2mortal(newSVpvn((char *)&ip_address, sizeof(ip_address)));
            XSRETURN(1);
        }
#ifdef HAS_GETHOSTBYNAME
        /* gethostbyname is not thread-safe */
        phe = gethostbyname(host);
        if (phe && phe->h_addrtype == AF_INET && phe->h_length == 4) {
            ST(0) = sv_2mortal(newSVpvn((char *)phe->h_addr, phe->h_length));
            XSRETURN(1);
        }
#endif /* HAS_GETHOSTBYNAME */
#endif /* HAS_GETADDRINFO */
        XSRETURN_UNDEF;
    }
void
inet_ntoa(ip_address_sv)
    SV *    ip_address_sv
    CODE:
    {
        STRLEN addrlen;
        struct in_addr addr;
        char * ip_address;
        if (DO_UTF8(ip_address_sv) && !sv_utf8_downgrade(ip_address_sv, 1))
            croak("Wide character in %s", "Socket::inet_ntoa");
        ip_address = SvPVbyte(ip_address_sv, addrlen);
        if (addrlen == sizeof(addr) || addrlen == 4)
            addr.s_addr =
                (unsigned long)(ip_address[0] & 0xFF) << 24 |
                (unsigned long)(ip_address[1] & 0xFF) << 16 |
                (unsigned long)(ip_address[2] & 0xFF) <<  8 |
                (unsigned long)(ip_address[3] & 0xFF);
        else
            croak("Bad arg length for %s, length is %" UVuf ", should be %" UVuf,
                    "Socket::inet_ntoa", (UV)addrlen, (UV)sizeof(addr));
        /* We could use inet_ntoa() but that is broken
         * in HP-UX + GCC + 64bitint (returns "0.0.0.0"),
         * so let's use this sprintf() workaround everywhere.
         * This is also more threadsafe than using inet_ntoa(). */
        ST(0) = sv_2mortal(Perl_newSVpvf(aTHX_ "%d.%d.%d.%d", /* IPv6? */
                                         (int)((addr.s_addr >> 24) & 0xFF),
                                         (int)((addr.s_addr >> 16) & 0xFF),
                                         (int)((addr.s_addr >>  8) & 0xFF),
                                         (int)( addr.s_addr        & 0xFF)));
    }
void
sockaddr_family(sockaddr)
        SV *    sockaddr
    PREINIT:
        STRLEN sockaddr_len;
        char *sockaddr_pv = SvPVbyte(sockaddr, sockaddr_len);
    CODE:
        if (sockaddr_len < STRUCT_OFFSET(struct sockaddr, sa_data))
            croak("Bad arg length for %s, length is %" UVuf ", should be at least %" UVuf,
                    "Socket::sockaddr_family", (UV)sockaddr_len,
                    (UV)STRUCT_OFFSET(struct sockaddr, sa_data));
        ST(0) = sv_2mortal(newSViv(((struct sockaddr*)sockaddr_pv)->sa_family));
void
pack_sockaddr_un(pathname)
        SV *    pathname
    CODE:
    {
#if defined(I_SYS_UN) || defined(WIN32)
        struct sockaddr_un sun_ad; /* fear using sun */
        STRLEN len;
        char * pathname_pv;
        int addr_len;
        if (!SvOK(pathname))
            croak("Undefined path for %s", "Socket::pack_sockaddr_un");
        Zero(&sun_ad, sizeof(sun_ad), char);
        sun_ad.sun_family = AF_UNIX;
        pathname_pv = SvPVbyte(pathname,len);
        if (len > sizeof(sun_ad.sun_path)) {
            warn("Path length (%" UVuf ") is longer than maximum supported length"
                 " (%" UVuf ") and will be truncated",
                 (UV)len, (UV)sizeof(sun_ad.sun_path));
            len = sizeof(sun_ad.sun_path);
        }
#  ifdef OS2    /* Name should start with \socket\ and contain backslashes! */
        {
            int off;
            char *s, *e;
            if (pathname_pv[0] != '/' && pathname_pv[0] != '\\')
                croak("Relative UNIX domain socket name '%s' unsupported",
                        pathname_pv);
            else if (len < 8
                    || pathname_pv[7] != '/' && pathname_pv[7] != '\\'
                    || !strnicmp(pathname_pv + 1, "socket", 6))
                off = 7;
            else
                off = 0;        /* Preserve names starting with \socket\ */
            Copy("\\socket", sun_ad.sun_path, off, char);
            Copy(pathname_pv, sun_ad.sun_path + off, len, char);
            s = sun_ad.sun_path + off - 1;
            e = s + len + 1;
            while (++s < e)
                if (*s = '/')
                    *s = '\\';
        }
#  else /* !( defined OS2 ) */
        Copy(pathname_pv, sun_ad.sun_path, len, char);
#  endif
        if (0) not_here("dummy");
        if (len > 1 && sun_ad.sun_path[0] == '\0') {
            /* Linux-style abstract-namespace socket.
             * The name is not a file name, but an array of arbitrary
             * character, starting with \0 and possibly including \0s,
             * therefore the length of the structure must denote the
             * end of that character array */
            addr_len = (char *)&(sun_ad.sun_path) - (char *)&sun_ad + len;
        } else {
            addr_len = sizeof(sun_ad);
        }
#  ifdef HAS_SOCKADDR_SA_LEN
        sun_ad.sun_len = addr_len;
#  endif
        ST(0) = sv_2mortal(newSVpvn((char *)&sun_ad, addr_len));
#else
        ST(0) = not_here("pack_sockaddr_un");
#endif
    }
void
unpack_sockaddr_un(sun_sv)
        SV *    sun_sv
    CODE:
    {
#if defined(I_SYS_UN) || defined(WIN32)
        struct sockaddr_un addr;
        STRLEN sockaddrlen;
        char * sun_ad;
        int addr_len = 0;
        if (!SvOK(sun_sv))
            croak("Undefined address for %s", "Socket::unpack_sockaddr_un");
        sun_ad = SvPVbyte(sun_sv,sockaddrlen);
#   if defined(__linux__) || defined(__CYGWIN__) || defined(sun) || defined(HAS_SOCKADDR_SA_LEN)
        /* On Linux, Cygwin, Solaris or *BSD sockaddrlen on sockets returned by accept,
         * recvfrom, getpeername and getsockname is not equal to sizeof(addr). */
        if (sockaddrlen < sizeof(addr)) {
            Copy(sun_ad, &addr, sockaddrlen, char);
            Zero(((char*)&addr) + sockaddrlen, sizeof(addr) - sockaddrlen, char);
        } else {
            Copy(sun_ad, &addr, sizeof(addr), char);
        }
#     ifdef HAS_SOCKADDR_SA_LEN
        /* In this case, sun_len must be checked */
        if (sockaddrlen != addr.sun_len)
            croak("Invalid arg sun_len field for %s, length is %" UVuf ", but sun_len is %" UVuf,
                    "Socket::unpack_sockaddr_un", (UV)sockaddrlen, (UV)addr.sun_len);
#     endif
#   else
        if (sockaddrlen != sizeof(addr))
            croak("Bad arg length for %s, length is %" UVuf ", should be %" UVuf,
                    "Socket::unpack_sockaddr_un", (UV)sockaddrlen, (UV)sizeof(addr));
        Copy(sun_ad, &addr, sizeof(addr), char);
#   endif
        if (addr.sun_family != AF_UNIX)
            croak("Bad address family for %s, got %d, should be %d",
                      "Socket::unpack_sockaddr_un", addr.sun_family, AF_UNIX);
#   ifdef __linux__
        if (addr.sun_path[0] == '\0') {
            /* Linux-style abstract socket address begins with a nul
             * and can contain nuls. */
            addr_len = (char *)&addr - (char *)&(addr.sun_path) + sockaddrlen;
        } else
#   endif
        {
#   if defined(HAS_SOCKADDR_SA_LEN)
            /* On *BSD sun_path not always ends with a '\0' */
            int maxlen = addr.sun_len - 2; /* should use STRUCT_OFFSET(struct sockaddr_un, sun_path) instead of 2 */
            if (maxlen > (int)sizeof(addr.sun_path))
                maxlen = (int)sizeof(addr.sun_path);
#   else
            const int maxlen = (int)sizeof(addr.sun_path);
#   endif
            while (addr_len < maxlen && addr.sun_path[addr_len])
                addr_len++;
        }
        ST(0) = sv_2mortal(newSVpvn(addr.sun_path, addr_len));
#else
        ST(0) = not_here("unpack_sockaddr_un");
#endif
    }
void
pack_sockaddr_in(port_sv, ip_address_sv)
        SV *    port_sv
        SV *    ip_address_sv
    CODE:
    {
        struct sockaddr_in sin;
        struct in_addr addr;
        STRLEN addrlen;
        unsigned short port = 0;
        char * ip_address;
        if (SvOK(port_sv)) {
            port = SvUV(port_sv);
            if (SvUV(port_sv) > 0xFFFF)
                warn("Port number above 0xFFFF, will be truncated to %d for %s",
                        port, "Socket::pack_sockaddr_in");
        }
        if (!SvOK(ip_address_sv))
            croak("Undefined address for %s", "Socket::pack_sockaddr_in");
        if (DO_UTF8(ip_address_sv) && !sv_utf8_downgrade(ip_address_sv, 1))
            croak("Wide character in %s", "Socket::pack_sockaddr_in");
        ip_address = SvPVbyte(ip_address_sv, addrlen);
        if (addrlen == sizeof(addr) || addrlen == 4)
            addr.s_addr =
                (unsigned int)(ip_address[0] & 0xFF) << 24 |
                (unsigned int)(ip_address[1] & 0xFF) << 16 |
                (unsigned int)(ip_address[2] & 0xFF) <<  8 |
                (unsigned int)(ip_address[3] & 0xFF);
        else
            croak("Bad arg length for %s, length is %" UVuf ", should be %" UVuf,
                    "Socket::pack_sockaddr_in", (UV)addrlen, (UV)sizeof(addr));
        Zero(&sin, sizeof(sin), char);
        sin.sin_family = AF_INET;
        sin.sin_port = htons(port);
        sin.sin_addr.s_addr = htonl(addr.s_addr);
#  ifdef HAS_SOCKADDR_SA_LEN
        sin.sin_len = sizeof(sin);
#  endif
        ST(0) = sv_2mortal(newSVpvn((char *)&sin, sizeof(sin)));
    }
void
unpack_sockaddr_in(sin_sv)
        SV *    sin_sv
    PPCODE:
    {
        STRLEN sockaddrlen;
        struct sockaddr_in addr;
        SV *ip_address_sv;
        char * sin;
        if (!SvOK(sin_sv))
            croak("Undefined address for %s", "Socket::unpack_sockaddr_in");
        sin = SvPVbyte(sin_sv,sockaddrlen);
        if (sockaddrlen != sizeof(addr)) {
            croak("Bad arg length for %s, length is %" UVuf ", should be %" UVuf,
                  "Socket::unpack_sockaddr_in", (UV)sockaddrlen, (UV)sizeof(addr));
        }
        Copy(sin, &addr, sizeof(addr), char);
        if (addr.sin_family != AF_INET) {
            croak("Bad address family for %s, got %d, should be %d",
                  "Socket::unpack_sockaddr_in", addr.sin_family, AF_INET);
        }
        ip_address_sv = newSVpvn((char *)&addr.sin_addr, sizeof(addr.sin_addr));
        if(GIMME_V == G_LIST) {
            EXTEND(SP, 2);
            mPUSHi(ntohs(addr.sin_port));
            mPUSHs(ip_address_sv);
        }
        else {
            mPUSHs(ip_address_sv);
        }
    }
void
pack_sockaddr_in6(port_sv, sin6_addr, scope_id=0, flowinfo=0)
        SV *    port_sv
        SV *    sin6_addr
        unsigned long   scope_id
        unsigned long   flowinfo
    CODE:
    {
#ifdef HAS_SOCKADDR_IN6
        unsigned short port = 0;
        struct sockaddr_in6 sin6;
        char * addrbytes;
        STRLEN addrlen;
        if (SvOK(port_sv)) {
            port = SvUV(port_sv);
            if (SvUV(port_sv) > 0xFFFF)
                warn("Port number above 0xFFFF, will be truncated to %d for %s",
                        port, "Socket::pack_sockaddr_in6");
        }
        if (!SvOK(sin6_addr))
            croak("Undefined address for %s", "Socket::pack_sockaddr_in6");
        if (DO_UTF8(sin6_addr) && !sv_utf8_downgrade(sin6_addr, 1))
            croak("Wide character in %s", "Socket::pack_sockaddr_in6");
        addrbytes = SvPVbyte(sin6_addr, addrlen);
        if (addrlen != sizeof(sin6.sin6_addr))
            croak("Bad arg length %s, length is %" UVuf ", should be %" UVuf,
                    "Socket::pack_sockaddr_in6", (UV)addrlen, (UV)sizeof(sin6.sin6_addr));
        Zero(&sin6, sizeof(sin6), char);
        sin6.sin6_family = AF_INET6;
        sin6.sin6_port = htons(port);
        sin6.sin6_flowinfo = htonl(flowinfo);
        Copy(addrbytes, &sin6.sin6_addr, sizeof(sin6.sin6_addr), char);
#  ifdef HAS_SIN6_SCOPE_ID
        sin6.sin6_scope_id = scope_id;
#  else
        if (scope_id != 0)
            warn("%s cannot represent non-zero scope_id %d",
                 "Socket::pack_sockaddr_in6", scope_id);
#  endif
#  ifdef HAS_SOCKADDR_SA_LEN
        sin6.sin6_len = sizeof(sin6);
#  endif
        ST(0) = sv_2mortal(newSVpvn((char *)&sin6, sizeof(sin6)));
#else
        PERL_UNUSED_VAR(port_sv);
        PERL_UNUSED_VAR(sin6_addr);
        ST(0) = not_here("pack_sockaddr_in6");
#endif
    }
void
unpack_sockaddr_in6(sin6_sv)
        SV *    sin6_sv
        PPCODE:
        {
#ifdef HAS_SOCKADDR_IN6
        STRLEN addrlen;
        struct sockaddr_in6 sin6;
        char * addrbytes;
        SV *ip_address_sv;
        if (!SvOK(sin6_sv))
                croak("Undefined address for %s", "Socket::unpack_sockaddr_in6");
        addrbytes = SvPVbyte(sin6_sv, addrlen);
        if (addrlen != sizeof(sin6))
                croak("Bad arg length for %s, length is %" UVuf
                      ", should be %" UVuf,
                      "Socket::unpack_sockaddr_in6", (UV)addrlen, (UV)sizeof(sin6));
        Copy(addrbytes, &sin6, sizeof(sin6), char);
        if (sin6.sin6_family != AF_INET6)
                croak("Bad address family for %s, got %d, should be %d",
                      "Socket::unpack_sockaddr_in6", sin6.sin6_family, AF_INET6);
        ip_address_sv = newSVpvn((char *)&sin6.sin6_addr, sizeof(sin6.sin6_addr));
        if(GIMME_V == G_LIST) {
            EXTEND(SP, 4);
            mPUSHi(ntohs(sin6.sin6_port));
            mPUSHs(ip_address_sv);
#  ifdef HAS_SIN6_SCOPE_ID
            mPUSHi(sin6.sin6_scope_id);
#  else
            mPUSHi(0);
#  endif
            mPUSHi(ntohl(sin6.sin6_flowinfo));
        }
        else {
            mPUSHs(ip_address_sv);
        }
#else
        PERL_UNUSED_VAR(sin6_sv);
        ST(0) = not_here("pack_sockaddr_in6");
#endif
        }
void
inet_ntop(af, ip_address_sv)
        int     af
        SV *    ip_address_sv
    CODE:
    {
#ifdef HAS_INETNTOP
        STRLEN addrlen;
#ifdef AF_INET6
        struct in6_addr addr;
        char str[INET6_ADDRSTRLEN];
#else
        struct in_addr addr;
        char str[INET_ADDRSTRLEN];
#endif
        char *ip_address;
        if (DO_UTF8(ip_address_sv) && !sv_utf8_downgrade(ip_address_sv, 1))
            croak("Wide character in %s", "Socket::inet_ntop");
        ip_address = SvPVbyte(ip_address_sv, addrlen);
        switch(af) {
            case AF_INET:
                if(addrlen != 4)
                    croak("Bad address length for Socket::inet_ntop on AF_INET;"
                            " got %" UVuf ", should be 4", (UV)addrlen);
                break;
#ifdef AF_INET6
            case AF_INET6:
                if(addrlen != 16)
                    croak("Bad address length for Socket::inet_ntop on AF_INET6;"
                            " got %" UVuf ", should be 16", (UV)addrlen);
                break;
#endif
            default:
#ifdef AF_INET6
#    define WANT_FAMILY "either AF_INET or AF_INET6"
#else
#    define WANT_FAMILY "AF_INET"
#endif
                croak("Bad address family for %s, got %d, should be " WANT_FAMILY,
                      "Socket::inet_ntop", af);
#undef WANT_FAMILY
        }
        if(addrlen < sizeof(addr)) {
            Copy(ip_address, &addr, addrlen, char);
            Zero(((char*)&addr) + addrlen, sizeof(addr) - addrlen, char);
        }
        else {
            Copy(ip_address, &addr, sizeof addr, char);
        }
        inet_ntop(af, &addr, str, sizeof str);
        ST(0) = sv_2mortal(newSVpvn(str, strlen(str)));
#else
        PERL_UNUSED_VAR(af);
        PERL_UNUSED_VAR(ip_address_sv);
        ST(0) = not_here("inet_ntop");
#endif
    }
void
inet_pton(af, host)
        int           af
        const char *  host
    CODE:
    {
#ifdef HAS_INETPTON
        int ok;
        int addrlen = 0;
#ifdef AF_INET6
        struct in6_addr ip_address;
#else
        struct in_addr ip_address;
#endif
        switch(af) {
            case AF_INET:
                addrlen = 4;
                break;
#ifdef AF_INET6
            case AF_INET6:
                addrlen = 16;
                break;
#endif
            default:
#ifdef AF_INET6
#    define WANT_FAMILY "either AF_INET or AF_INET6"
#else
#    define WANT_FAMILY "AF_INET"
#endif
                croak("Bad address family for %s, got %d, should be " WANT_FAMILY, "Socket::inet_pton", af);
#undef WANT_FAMILY
        }
        ok = (*host != '\0') && inet_pton(af, host, &ip_address);
        ST(0) = sv_newmortal();
        if (ok) {
                sv_setpvn( ST(0), (char *)&ip_address, addrlen);
        }
#else
        PERL_UNUSED_VAR(af);
        PERL_UNUSED_VAR(host);
        ST(0) = not_here("inet_pton");
#endif
    }
void
pack_ip_mreq(multiaddr, interface=&PL_sv_undef)
        SV *    multiaddr
        SV *    interface
    CODE:
    {
#ifdef HAS_IP_MREQ
        struct ip_mreq mreq;
        char * multiaddrbytes;
        char * interfacebytes;
        STRLEN len;
        if (DO_UTF8(multiaddr) && !sv_utf8_downgrade(multiaddr, 1))
            croak("Wide character in %s", "Socket::pack_ip_mreq");
        multiaddrbytes = SvPVbyte(multiaddr, len);
        if (len != sizeof(mreq.imr_multiaddr))
            croak("Bad arg length %s, length is %" UVuf ", should be %" UVuf,
                    "Socket::pack_ip_mreq", (UV)len, (UV)sizeof(mreq.imr_multiaddr));
        Zero(&mreq, sizeof(mreq), char);
        Copy(multiaddrbytes, &mreq.imr_multiaddr, sizeof(mreq.imr_multiaddr), char);
        if(SvOK(interface)) {
            if (DO_UTF8(interface) && !sv_utf8_downgrade(interface, 1))
                croak("Wide character in %s", "Socket::pack_ip_mreq");
            interfacebytes = SvPVbyte(interface, len);
            if (len != sizeof(mreq.imr_interface))
                croak("Bad arg length %s, length is %" UVuf ", should be %" UVuf,
                        "Socket::pack_ip_mreq", (UV)len, (UV)sizeof(mreq.imr_interface));
            Copy(interfacebytes, &mreq.imr_interface, sizeof(mreq.imr_interface), char);
        }
        else
            mreq.imr_interface.s_addr = INADDR_ANY;
        ST(0) = sv_2mortal(newSVpvn((char *)&mreq, sizeof(mreq)));
#else
        not_here("pack_ip_mreq");
#endif
    }
void
unpack_ip_mreq(mreq_sv)
        SV * mreq_sv
    PPCODE:
    {
#ifdef HAS_IP_MREQ
        struct ip_mreq mreq;
        STRLEN mreqlen;
        char * mreqbytes = SvPVbyte(mreq_sv, mreqlen);
        if (mreqlen != sizeof(mreq))
            croak("Bad arg length for %s, length is %" UVuf ", should be %" UVuf,
                    "Socket::unpack_ip_mreq", (UV)mreqlen, (UV)sizeof(mreq));
        Copy(mreqbytes, &mreq, sizeof(mreq), char);
        EXTEND(SP, 2);
        mPUSHp((char *)&mreq.imr_multiaddr, sizeof(mreq.imr_multiaddr));
        mPUSHp((char *)&mreq.imr_interface, sizeof(mreq.imr_interface));
#else
        not_here("unpack_ip_mreq");
#endif
    }
void
pack_ip_mreq_source(multiaddr, source, interface=&PL_sv_undef)
        SV *    multiaddr
        SV *    source
        SV *    interface
    CODE:
    {
#if defined(HAS_IP_MREQ_SOURCE) && defined (IP_ADD_SOURCE_MEMBERSHIP)
        struct ip_mreq_source mreq;
        char * multiaddrbytes;
        char * sourcebytes;
        char * interfacebytes;
        STRLEN len;
        if (DO_UTF8(multiaddr) && !sv_utf8_downgrade(multiaddr, 1))
            croak("Wide character in %s", "Socket::pack_ip_mreq_source");
        multiaddrbytes = SvPVbyte(multiaddr, len);
        if (len != sizeof(mreq.imr_multiaddr))
            croak("Bad arg length %s, length is %" UVuf ", should be %" UVuf,
                    "Socket::pack_ip_mreq", (UV)len, (UV)sizeof(mreq.imr_multiaddr));
        if (DO_UTF8(source) && !sv_utf8_downgrade(source, 1))
            croak("Wide character in %s", "Socket::pack_ip_mreq_source");
        if (len != sizeof(mreq.imr_sourceaddr))
            croak("Bad arg length %s, length is %" UVuf ", should be %" UVuf,
                    "Socket::pack_ip_mreq", (UV)len, (UV)sizeof(mreq.imr_sourceaddr));
        sourcebytes = SvPVbyte(source, len);
        Zero(&mreq, sizeof(mreq), char);
        Copy(multiaddrbytes, &mreq.imr_multiaddr, sizeof(mreq.imr_multiaddr), char);
        Copy(sourcebytes, &mreq.imr_sourceaddr, sizeof(mreq.imr_sourceaddr), char);
        if(SvOK(interface)) {
            if (DO_UTF8(interface) && !sv_utf8_downgrade(interface, 1))
                croak("Wide character in %s", "Socket::pack_ip_mreq");
            interfacebytes = SvPVbyte(interface, len);
            if (len != sizeof(mreq.imr_interface))
                croak("Bad arg length %s, length is %" UVuf ", should be %" UVuf,
                        "Socket::pack_ip_mreq", (UV)len, (UV)sizeof(mreq.imr_interface));
            Copy(interfacebytes, &mreq.imr_interface, sizeof(mreq.imr_interface), char);
        }
        else
            mreq.imr_interface.s_addr = INADDR_ANY;
        ST(0) = sv_2mortal(newSVpvn((char *)&mreq, sizeof(mreq)));
#else
        PERL_UNUSED_VAR(multiaddr);
        PERL_UNUSED_VAR(source);
        not_here("pack_ip_mreq_source");
#endif
    }
void
unpack_ip_mreq_source(mreq_sv)
        SV * mreq_sv
    PPCODE:
    {
#if defined(HAS_IP_MREQ_SOURCE) && defined (IP_ADD_SOURCE_MEMBERSHIP)
        struct ip_mreq_source mreq;
        STRLEN mreqlen;
        char * mreqbytes = SvPVbyte(mreq_sv, mreqlen);
        if (mreqlen != sizeof(mreq))
            croak("Bad arg length for %s, length is %" UVuf ", should be %" UVuf,
                    "Socket::unpack_ip_mreq_source", (UV)mreqlen, (UV)sizeof(mreq));
        Copy(mreqbytes, &mreq, sizeof(mreq), char);
        EXTEND(SP, 3);
        mPUSHp((char *)&mreq.imr_multiaddr, sizeof(mreq.imr_multiaddr));
        mPUSHp((char *)&mreq.imr_sourceaddr, sizeof(mreq.imr_sourceaddr));
        mPUSHp((char *)&mreq.imr_interface, sizeof(mreq.imr_interface));
#else
        PERL_UNUSED_VAR(mreq_sv);
        not_here("unpack_ip_mreq_source");
#endif
    }
void
pack_ipv6_mreq(multiaddr, ifindex)
        SV *    multiaddr
        unsigned int    ifindex
    CODE:
    {
#ifdef HAS_IPV6_MREQ
        struct ipv6_mreq mreq;
        char * multiaddrbytes;
        STRLEN len;
        if (DO_UTF8(multiaddr) && !sv_utf8_downgrade(multiaddr, 1))
            croak("Wide character in %s", "Socket::pack_ipv6_mreq");
        multiaddrbytes = SvPVbyte(multiaddr, len);
        if (len != sizeof(mreq.ipv6mr_multiaddr))
            croak("Bad arg length %s, length is %" UVuf ", should be %" UVuf,
                    "Socket::pack_ipv6_mreq", (UV)len, (UV)sizeof(mreq.ipv6mr_multiaddr));
        Zero(&mreq, sizeof(mreq), char);
        Copy(multiaddrbytes, &mreq.ipv6mr_multiaddr, sizeof(mreq.ipv6mr_multiaddr), char);
        mreq.ipv6mr_interface = ifindex;
        ST(0) = sv_2mortal(newSVpvn((char *)&mreq, sizeof(mreq)));
#else
        PERL_UNUSED_VAR(multiaddr);
        PERL_UNUSED_VAR(ifindex);
        not_here("pack_ipv6_mreq");
#endif
    }
void
unpack_ipv6_mreq(mreq_sv)
        SV * mreq_sv
    PPCODE:
    {
#ifdef HAS_IPV6_MREQ
        struct ipv6_mreq mreq;
        STRLEN mreqlen;
        char * mreqbytes = SvPVbyte(mreq_sv, mreqlen);
        if (mreqlen != sizeof(mreq))
            croak("Bad arg length for %s, length is %" UVuf ", should be %" UVuf,
                    "Socket::unpack_ipv6_mreq", (UV)mreqlen, (UV)sizeof(mreq));
        Copy(mreqbytes, &mreq, sizeof(mreq), char);
        EXTEND(SP, 2);
        mPUSHp((char *)&mreq.ipv6mr_multiaddr, sizeof(mreq.ipv6mr_multiaddr));
        mPUSHi(mreq.ipv6mr_interface);
#else
        PERL_UNUSED_VAR(mreq_sv);
        not_here("unpack_ipv6_mreq");
#endif
    }