//
// Copyright (c) ZeroC, Inc. All rights reserved.
//

//
// The following is required on HP-UX in order to bring in
// the definition for the ip_mreq structure.
//
#if defined(__hpux)
#  undef _XOPEN_SOURCE_EXTENDED
#  define _XOPEN_SOURCE
#  include <netinet/in.h>
#endif

#include <IceUtil/DisableWarnings.h>
#include <Ice/Network.h>
#include <Ice/NetworkProxy.h>
#include <IceUtil/StringUtil.h>
#include <Ice/StringConverter.h>
#include <Ice/LocalException.h>
#include <Ice/ProtocolInstance.h> // For setTcpBufSize
#include <Ice/Properties.h> // For setTcpBufSize
#include <Ice/LoggerUtil.h> // For setTcpBufSize
#include <Ice/Buffer.h>
#include <IceUtil/Random.h>
#include <functional>

// TODO: fix this warning
#if defined(_MSC_VER)
#   pragma warning(disable:4244) // 'argument': conversion from 'int' to 'u_short', possible loss of data
#endif

#if defined(_WIN32)
#   include <winsock2.h>
#   include <ws2tcpip.h>
#   ifdef __MINGW32__
#       include <wincrypt.h>
#   endif
#   include <iphlpapi.h>
#   include <Mswsock.h>
#   include <mstcpip.h>
#else
#   include <net/if.h>
#   include <sys/ioctl.h>
#endif

#if defined(__linux__) || defined(__APPLE__) || defined(__FreeBSD__)
#  include <ifaddrs.h>
#elif defined(__sun)
#  include <sys/sockio.h>
#endif

#if defined(__GNUC__) && (__GNUC__ < 5)
#  pragma GCC diagnostic ignored "-Wmissing-field-initializers"
#endif

#if defined(__MINGW32__)
//
// Work-around for missing definitions in MinGW Windows headers
//
#   ifndef IPV6_V6ONLY
#       define IPV6_V6ONLY 27
#   endif

extern "C"
{
    WINSOCK_API_LINKAGE int WSAAPI inet_pton(INT, PCTSTR, PVOID);
}
#endif

using namespace std;
using namespace Ice;
using namespace IceInternal;

#ifdef _WIN32
int
IceInternal::getSystemErrno()
{
    return GetLastError();
}
#else
int
IceInternal::getSystemErrno()
{
    return errno;
}
#endif

namespace
{

struct AddressCompare
{
public:

    bool
    operator()(const Address& lhs, const Address& rhs) const
    {
        return compareAddress(lhs, rhs) < 0;
    }
};

#ifndef ICE_CPP11_COMPILER

struct AddressIsIPv6 : public unary_function<Address, bool>
{
public:

    bool
    operator()(const Address& ss) const
    {
        return ss.saStorage.ss_family == AF_INET6;
    }
};
#endif

void
sortAddresses(vector<Address>& addrs, ProtocolSupport protocol, Ice::EndpointSelectionType selType, bool preferIPv6)
{
    if(selType == Ice::ICE_ENUM(EndpointSelectionType, Random))
    {
        IceUtilInternal::shuffle(addrs.begin(), addrs.end());
    }

    if(protocol == EnableBoth)
    {
#ifdef ICE_CPP11_COMPILER
        if(preferIPv6)
        {
            stable_partition(addrs.begin(), addrs.end(),
                             [](const Address& ss)
                             {
                                 return ss.saStorage.ss_family == AF_INET6;
                             });
        }
        else
        {
            stable_partition(addrs.begin(), addrs.end(),
                             [](const Address& ss)
                             {
                                 return ss.saStorage.ss_family != AF_INET6;
                             });
        }
#else
        if(preferIPv6)
        {
            stable_partition(addrs.begin(), addrs.end(), AddressIsIPv6());
        }
        else
        {
            stable_partition(addrs.begin(), addrs.end(), not1(AddressIsIPv6()));
        }
#endif
    }
}

void
setTcpNoDelay(SOCKET fd)
{
    int flag = 1;
    if(setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, reinterpret_cast<char*>(&flag), int(sizeof(int))) == SOCKET_ERROR)
    {
        closeSocketNoThrow(fd);
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }
}

void
setKeepAlive(SOCKET fd)
{
    int flag = 1;
    if(setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, reinterpret_cast<char*>(&flag), int(sizeof(int))) == SOCKET_ERROR)
    {
        closeSocketNoThrow(fd);
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }
}

SOCKET
createSocketImpl(bool udp, int family)
{
    SOCKET fd;
    if(udp)
    {
        fd = socket(family, SOCK_DGRAM, IPPROTO_UDP);
    }
    else
    {
        fd = socket(family, SOCK_STREAM, IPPROTO_TCP);
    }

    if(fd == INVALID_SOCKET)
    {
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }

    if(!udp)
    {
        setTcpNoDelay(fd);
        setKeepAlive(fd);
    }

    return fd;
}

vector<Address>
getLocalAddresses(ProtocolSupport protocol, bool includeLoopback, bool singleAddressPerInterface)
{
    vector<Address> result;

#if defined(_WIN32)
    DWORD family;
    switch(protocol)
    {
        case EnableIPv4:
            family = AF_INET;
            break;
        case EnableIPv6:
            family = AF_INET6;
            break;
        default:
            family = AF_UNSPEC;
            break;
    }

    DWORD size = 0;
    DWORD rv = GetAdaptersAddresses(family, 0, ICE_NULLPTR, ICE_NULLPTR, &size);
    if(rv == ERROR_BUFFER_OVERFLOW)
    {
        PIP_ADAPTER_ADDRESSES adapter_addresses = (PIP_ADAPTER_ADDRESSES) malloc(size);
        rv = GetAdaptersAddresses(family, 0, ICE_NULLPTR, adapter_addresses, &size);
        if(rv == ERROR_SUCCESS)
        {
            for(PIP_ADAPTER_ADDRESSES aa = adapter_addresses; aa != ICE_NULLPTR; aa = aa->Next)
            {
                if(aa->OperStatus != IfOperStatusUp)
                {
                    continue;
                }
                for(PIP_ADAPTER_UNICAST_ADDRESS ua = aa->FirstUnicastAddress; ua != ICE_NULLPTR; ua = ua->Next)
                {
                    Address addr;
                    memcpy(&addr.saStorage, ua->Address.lpSockaddr, ua->Address.iSockaddrLength);
                    if(addr.saStorage.ss_family == AF_INET && protocol != EnableIPv6)
                    {
                        if(addr.saIn.sin_addr.s_addr != 0 &&
                           (includeLoopback || addr.saIn.sin_addr.s_addr != htonl(INADDR_LOOPBACK)))
                        {
                            result.push_back(addr);
                            if(singleAddressPerInterface)
                            {
                                break; // One address is enough for each interface.
                            }
                        }
                    }
                    else if(addr.saStorage.ss_family == AF_INET6 && protocol != EnableIPv4)
                    {
                        if(!IN6_IS_ADDR_UNSPECIFIED(&addr.saIn6.sin6_addr) &&
                           (includeLoopback || !IN6_IS_ADDR_LOOPBACK(&addr.saIn6.sin6_addr)))
                        {
                            result.push_back(addr);
                            if(singleAddressPerInterface)
                            {
                                break; // One address is enough for each interface.
                            }
                        }
                    }
                }
            }
        }

        free(adapter_addresses);
    }
#elif defined(__linux__) || defined(__APPLE__) || defined(__FreeBSD__)
    struct ifaddrs* ifap;
    if(::getifaddrs(&ifap) == SOCKET_ERROR)
    {
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }

    struct ifaddrs* curr = ifap;
    set<string> interfaces;
    while(curr != 0)
    {
        if(curr->ifa_addr && (includeLoopback || !(curr->ifa_flags & IFF_LOOPBACK)))
        {
            if(curr->ifa_addr->sa_family == AF_INET && protocol != EnableIPv6)
            {
                Address addr;
                memcpy(&addr.saStorage, curr->ifa_addr, sizeof(sockaddr_in));
                if(addr.saIn.sin_addr.s_addr != 0)
                {
                    if(!singleAddressPerInterface || interfaces.find(curr->ifa_name) == interfaces.end())
                    {
                        result.push_back(addr);
                        interfaces.insert(curr->ifa_name);
                    }
                }
            }
            else if(curr->ifa_addr->sa_family == AF_INET6 && protocol != EnableIPv4)
            {
                Address addr;
                memcpy(&addr.saStorage, curr->ifa_addr, sizeof(sockaddr_in6));
                if(!IN6_IS_ADDR_UNSPECIFIED(&addr.saIn6.sin6_addr))
                {
                    if(!singleAddressPerInterface || interfaces.find(curr->ifa_name) == interfaces.end())
                    {
                        result.push_back(addr);
                        interfaces.insert(curr->ifa_name);
                    }
                }
            }
        }

        curr = curr->ifa_next;
    }

    ::freeifaddrs(ifap);
#else
    for(int i = 0; i < 2; i++)
    {
        if((i == 0 && protocol == EnableIPv6) || (i == 1 && protocol == EnableIPv4))
        {
            continue;
        }
        SOCKET fd = createSocketImpl(false, i == 0 ? AF_INET : AF_INET6);

#ifdef _AIX
        int cmd = CSIOCGIFCONF;
#else
        int cmd = SIOCGIFCONF;
#endif
        struct ifconf ifc;
        int numaddrs = 10;
        int old_ifc_len = 0;

        //
        // Need to call ioctl multiple times since we do not know up front
        // how many addresses there will be, and thus how large a buffer we need.
        // We keep increasing the buffer size until subsequent calls return
        // the same length, meaning we have all the addresses.
        //
        while(true)
        {
            int bufsize = numaddrs * static_cast<int>(sizeof(struct ifreq));
            ifc.ifc_len = bufsize;
            ifc.ifc_buf = (char*)malloc(bufsize);

            int rs = ioctl(fd, cmd, &ifc);
            if(rs == SOCKET_ERROR)
            {
                free(ifc.ifc_buf);
                closeSocketNoThrow(fd);
                throw SocketException(__FILE__, __LINE__, getSocketErrno());
            }
            else if(ifc.ifc_len == old_ifc_len)
            {
                //
                // Returned same length twice in a row, finished.
                //
                break;
            }
            else
            {
                old_ifc_len = ifc.ifc_len;
            }

            numaddrs += 10;
            free(ifc.ifc_buf);
        }
        closeSocket(fd);

        numaddrs = ifc.ifc_len / static_cast<int>(sizeof(struct ifreq));
        struct ifreq* ifr = ifc.ifc_req;
        set<string> interfaces;
        for(int j = 0; j < numaddrs; ++j)
        {
            if(!(ifr[j].ifr_flags & IFF_LOOPBACK)) // Don't include loopback interface addresses
            {
                //
                // On Solaris the above Loopback check does not always work so we double
                // check the address below. Solaris also returns duplicate entries that need
                // to be filtered out.
                //
                if(ifr[j].ifr_addr.sa_family == AF_INET && protocol != EnableIPv6)
                {
                    Address addr;
                    memcpy(&addr.saStorage, &ifr[j].ifr_addr, sizeof(sockaddr_in));
                    if(addr.saIn.sin_addr.s_addr != 0 &&
                       (includeLoopback || addr.saIn.sin_addr.s_addr != htonl(INADDR_LOOPBACK)))
                    {
                        if(!singleAddressPerInterface || interfaces.find(ifr[j].ifr_name) == interfaces.end())
                        {
                            result.push_back(addr);
                            interfaces.insert(ifr[j].ifr_name);
                        }
                    }
                }
                else if(ifr[j].ifr_addr.sa_family == AF_INET6 && protocol != EnableIPv4)
                {
                    Address addr;
                    memcpy(&addr.saStorage, &ifr[j].ifr_addr, sizeof(sockaddr_in6));
                    if(!IN6_IS_ADDR_UNSPECIFIED(&addr.saIn6.sin6_addr) &&
                       (includeLoopback || !IN6_IS_ADDR_LOOPBACK(&addr.saIn6.sin6_addr)))
                    {
                        if(!singleAddressPerInterface || interfaces.find(ifr[j].ifr_name) == interfaces.end())
                        {
                            result.push_back(addr);
                            interfaces.insert(ifr[j].ifr_name);
                        }
                    }
                }
            }
        }
        free(ifc.ifc_buf);
    }
#endif

    //
    // Remove potential duplicates from the result.
    //
    set<Address, AddressCompare> seen;
    vector<Address> tmp;
    tmp.swap(result);
    for(vector<Address>::const_iterator p = tmp.begin(); p != tmp.end(); ++p)
    {
        if(seen.find(*p) == seen.end())
        {
            result.push_back(*p);
            seen.insert(*p);
        }
    }
    return result;
}

bool
isLinklocal(const Address& addr)
{
    if(addr.saStorage.ss_family == AF_INET6)
    {
        return IN6_IS_ADDR_LINKLOCAL(&addr.saIn6.sin6_addr);
    }
    else if(addr.saStorage.ss_family == AF_INET)
    {
        // Check for 169.254.X.X in network order
        return (addr.saIn.sin_addr.s_addr & 0xFF) == 169 && ((addr.saIn.sin_addr.s_addr & 0xFF00)>>8) == 254;
    }
    return false;
}

bool
isWildcard(const string& host, ProtocolSupport protocol, bool& ipv4)
{
    Address addr = getAddressForServer(host, 0, protocol, true, false);
    if(addr.saStorage.ss_family == AF_INET)
    {
        if(addr.saIn.sin_addr.s_addr == INADDR_ANY)
        {
            ipv4 = true;
            return true;
        }
    }
    else if(addr.saStorage.ss_family == AF_INET6)
    {
        if(IN6_IS_ADDR_UNSPECIFIED(&addr.saIn6.sin6_addr))
        {
            ipv4 = false;
            return true;
        }
    }
    return false;
}

int
getInterfaceIndex(const string& intf)
{
    if(intf.empty())
    {
        return 0;
    }

    string name;
    bool isAddr;
    in6_addr addr;
    string::size_type pos = intf.find("%");
    if(pos != string::npos)
    {
        //
        // If it's a link-local address, use the zone indice.
        //
        isAddr = false;
        name = intf.substr(pos + 1);
    }
    else
    {
        //
        // Then check if it's an IPv6 address. If it's an address we'll
        // look for the interface index by address.
        //
        isAddr = inet_pton(AF_INET6, intf.c_str(), &addr) > 0;
        name = intf;
    }

    //
    // Check if index
    //
    int index = -1;
    istringstream p(name);
    if((p >> index) && p.eof())
    {
        return index;
    }

#ifdef _WIN32
    IP_ADAPTER_ADDRESSES addrs;
    ULONG buflen = 0;
    if(::GetAdaptersAddresses(AF_INET6, 0, 0, &addrs, &buflen) == ERROR_BUFFER_OVERFLOW)
    {
        PIP_ADAPTER_ADDRESSES paddrs;
        char* buf = new char[buflen];
        paddrs = reinterpret_cast<PIP_ADAPTER_ADDRESSES>(buf);
        if(::GetAdaptersAddresses(AF_INET6, 0, 0, paddrs, &buflen) == NO_ERROR)
        {
            while(paddrs)
            {
                if(isAddr)
                {
                    PIP_ADAPTER_UNICAST_ADDRESS ipAddr = paddrs->FirstUnicastAddress;
                    while(ipAddr)
                    {
                        if(ipAddr->Address.lpSockaddr->sa_family == AF_INET6)
                        {
                            struct sockaddr_in6* ipv6Addr =
                                reinterpret_cast<struct sockaddr_in6*>(ipAddr->Address.lpSockaddr);
                            if(memcmp(&addr, &ipv6Addr->sin6_addr, sizeof(in6_addr)) == 0)
                            {
                                break;
                            }
                        }
                        ipAddr = ipAddr->Next;
                    }
                    if(ipAddr)
                    {
                        index = paddrs->Ipv6IfIndex;
                        break;
                    }
                }
                else
                {
                    //
                    // Don't need to pass a wide string converter as the wide string
                    // come from Windows API.
                    //
                    if(wstringToString(paddrs->FriendlyName, getProcessStringConverter()) == name)
                    {
                        index = paddrs->Ipv6IfIndex;
                        break;
                    }
                }
                paddrs = paddrs->Next;
            }
        }
        delete[] buf;
    }
    if(index < 0) // interface not found
    {
        throw Ice::SocketException(__FILE__, __LINE__, WSAEINVAL);
    }
#elif !defined(__hpux)

    //
    // Look for an interface with a matching IP address
    //
    if(isAddr)
    {
#  if defined(__linux__) || defined(__APPLE__) || defined(__FreeBSD__)
        struct ifaddrs* ifap;
        if(::getifaddrs(&ifap) != SOCKET_ERROR)
        {
            struct ifaddrs* curr = ifap;
            while(curr != 0)
            {
                if(curr->ifa_addr && curr->ifa_addr->sa_family == AF_INET6)
                {
                    struct sockaddr_in6* ipv6Addr = reinterpret_cast<struct sockaddr_in6*>(curr->ifa_addr);
                    if(memcmp(&addr, &ipv6Addr->sin6_addr, sizeof(in6_addr)) == 0)
                    {
                        index = static_cast<int>(if_nametoindex(curr->ifa_name));
                        break;
                    }
                }
                curr = curr->ifa_next;
            }
            ::freeifaddrs(ifap);
        }
#  else
        SOCKET fd = createSocketImpl(false, AF_INET6);
#    ifdef _AIX
        int cmd = CSIOCGIFCONF;
#    else
        int cmd = SIOCGIFCONF;
#    endif
        struct ifconf ifc;
        int numaddrs = 10;
        int old_ifc_len = 0;

        //
        // Need to call ioctl multiple times since we do not know up front
        // how many addresses there will be, and thus how large a buffer we need.
        // We keep increasing the buffer size until subsequent calls return
        // the same length, meaning we have all the addresses.
        //
        while(true)
        {
            int bufsize = numaddrs * static_cast<int>(sizeof(struct ifreq));
            ifc.ifc_len = bufsize;
            ifc.ifc_buf = (char*)malloc(bufsize);

            int rs = ioctl(fd, cmd, &ifc);
            if(rs == SOCKET_ERROR)
            {
                free(ifc.ifc_buf);
                ifc.ifc_buf = 0;
                break;
            }
            else if(ifc.ifc_len == old_ifc_len)
            {
                //
                // Returned same length twice in a row, finished.
                //
                break;
            }
            else
            {
                old_ifc_len = ifc.ifc_len;
            }
            numaddrs += 10;
            free(ifc.ifc_buf);
        }
        closeSocketNoThrow(fd);

        if(ifc.ifc_buf)
        {
            numaddrs = ifc.ifc_len / static_cast<int>(sizeof(struct ifreq));
            struct ifreq* ifr = ifc.ifc_req;
            for(int i = 0; i < numaddrs; ++i)
            {
                if(ifr[i].ifr_addr.sa_family == AF_INET6)
                {
                    struct sockaddr_in6* ipv6Addr = reinterpret_cast<struct sockaddr_in6*>(&ifr[i].ifr_addr);
                    if(memcmp(&addr, &ipv6Addr->sin6_addr, sizeof(in6_addr)) == 0)
                    {
                        index = static_cast<int>(if_nametoindex(ifr[i].ifr_name));
                        break;
                    }
                }
            }
            free(ifc.ifc_buf);
        }
#  endif
    }
    else // Look for an interface with the given name.
    {
        index = static_cast<int>(if_nametoindex(name.c_str()));
    }
    if(index <= 0)
    {
        // index == 0 if if_nametoindex returned 0, < 0 if name wasn't found
        throw Ice::SocketException(__FILE__, __LINE__, index == 0 ? getSocketErrno() : ENXIO);
    }
#endif

    return index;
}

struct in_addr
getInterfaceAddress(const string& name)
{
    struct in_addr addr;
    addr.s_addr = INADDR_ANY;
    if(name.empty())
    {
        return addr;
    }

    if(inet_pton(AF_INET, name.c_str(), &addr) > 0)
    {
        return addr;
    }

#ifdef _WIN32
    IP_ADAPTER_ADDRESSES addrs;
    ULONG buflen = 0;
    if(::GetAdaptersAddresses(AF_INET, 0, 0, &addrs, &buflen) == ERROR_BUFFER_OVERFLOW)
    {
        PIP_ADAPTER_ADDRESSES paddrs;
        char* buf = new char[buflen];
        paddrs = reinterpret_cast<PIP_ADAPTER_ADDRESSES>(buf);
        if(::GetAdaptersAddresses(AF_INET, 0, 0, paddrs, &buflen) == NO_ERROR)
        {
            while(paddrs)
            {
                //
                // Don't need to pass a wide string converter as the wide string come
                // from Windows API.
                //
                if(wstringToString(paddrs->FriendlyName, getProcessStringConverter()) == name)
                {
                    struct sockaddr_in addrin;
                    memcpy(&addrin, paddrs->FirstUnicastAddress->Address.lpSockaddr,
                           paddrs->FirstUnicastAddress->Address.iSockaddrLength);
                    delete[] buf;
                    return addrin.sin_addr;
                }
                paddrs = paddrs->Next;
            }
        }
        delete[] buf;
    }
    throw Ice::SocketException(__FILE__, __LINE__, WSAEINVAL);
#else
    ifreq if_address;
    strcpy(if_address.ifr_name, name.c_str());

    SOCKET fd = createSocketImpl(false, AF_INET);
    int rc = ioctl(fd, SIOCGIFADDR, &if_address);
    closeSocketNoThrow(fd);
    if(rc == SOCKET_ERROR)
    {
        throw Ice::SocketException(__FILE__, __LINE__, getSocketErrno());
    }
    return reinterpret_cast<struct sockaddr_in*>(&if_address.ifr_addr)->sin_addr;
#endif
}

int
getAddressStorageSize(const Address& addr)
{
    int size = 0;
    if(addr.saStorage.ss_family == AF_INET)
    {
        size = sizeof(sockaddr_in);
    }
    else if(addr.saStorage.ss_family == AF_INET6)
    {
        size = sizeof(sockaddr_in6);
    }
    return size;
}

vector<Address>
getLoopbackAddresses(ProtocolSupport protocol, int port = 0)
{
    vector<Address> result;

    Address addr;
    memset(&addr.saStorage, 0, sizeof(sockaddr_storage));

    //
    // We don't use getaddrinfo when host is empty as it's not portable (some old Linux
    // versions don't support it).
    //
    if(protocol != EnableIPv4)
    {
        addr.saIn6.sin6_family = AF_INET6;
        addr.saIn6.sin6_port = htons(port);
        addr.saIn6.sin6_addr = in6addr_loopback;
        result.push_back(addr);
    }
    if(protocol != EnableIPv6)
    {
        addr.saIn.sin_family = AF_INET;
        addr.saIn.sin_port = htons(port);
        addr.saIn.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
        result.push_back(addr);
    }
    return result;
}

}

ReadyCallback::~ReadyCallback()
{
    // Out of line to avoid weak vtable
}

NativeInfo::~NativeInfo()
{
    // Out of line to avoid weak vtable
}

void
NativeInfo::setReadyCallback(const ReadyCallbackPtr& callback)
{
    _readyCallback = callback;
}

#ifdef ICE_USE_IOCP

IceInternal::AsyncInfo::AsyncInfo(SocketOperation s)
{
    ZeroMemory(this, sizeof(AsyncInfo));
    status = s;
}

void
IceInternal::NativeInfo::initialize(HANDLE handle, ULONG_PTR key)
{
    _handle = handle;
    _key = key;
}

void
IceInternal::NativeInfo::completed(SocketOperation operation)
{
    if(!PostQueuedCompletionStatus(_handle, 0, _key, getAsyncInfo(operation)))
    {
        throw Ice::SocketException(__FILE__, __LINE__, GetLastError());
    }
}

#else

void
IceInternal::NativeInfo::setNewFd(SOCKET fd)
{
    assert(_fd == INVALID_SOCKET); // This can only be called once, when the current socket isn't set yet.
    _newFd = fd;
}

bool
IceInternal::NativeInfo::newFd()
{
    if(_newFd == INVALID_SOCKET)
    {
        return false;
    }
    assert(_fd == INVALID_SOCKET);
    swap(_fd, _newFd);
    return true;
}

#endif

bool
IceInternal::noMoreFds(int error)
{
#if defined(_WIN32)
    return error == WSAEMFILE;
#else
    return error == EMFILE || error == ENFILE;
#endif
}

string
IceInternal::errorToStringDNS(int error)
{
#if defined(_WIN32)
    return IceUtilInternal::errorToString(error);
#else
    return gai_strerror(error);
#endif
}

vector<Address>
IceInternal::getAddresses(const string& host, int port, ProtocolSupport protocol, Ice::EndpointSelectionType selType,
                          bool preferIPv6, bool canBlock)
{
    vector<Address> result;

    //
    // We don't use getaddrinfo when host is empty as it's not portable (some old Linux
    // versions don't support it).
    //
    if(host.empty())
    {
        result = getLoopbackAddresses(protocol, port);
        sortAddresses(result, protocol, selType, preferIPv6);
        return result;
    }

    Address addr;
    memset(&addr.saStorage, 0, sizeof(sockaddr_storage));

    struct addrinfo* info = 0;
    int retry = 5;

    struct addrinfo hints = {};
    if(protocol == EnableIPv4)
    {
        hints.ai_family = PF_INET;
    }
    else if(protocol == EnableIPv6)
    {
        hints.ai_family = PF_INET6;
    }
    else
    {
        hints.ai_family = PF_UNSPEC;
    }

    if(!canBlock)
    {
        hints.ai_flags = AI_NUMERICHOST;
    }

    int rs = 0;
    do
    {
        rs = getaddrinfo(host.c_str(), 0, &hints, &info);
    }
    while(info == 0 && rs == EAI_AGAIN && --retry >= 0);

    // In theory, getaddrinfo should only return EAI_NONAME if
    // AI_NUMERICHOST is specified and the host name is not a IP
    // address. However on some platforms (e.g. macOS 10.4.x)
    // EAI_NODATA is also returned so we also check for it.
#ifdef EAI_NODATA
    if(!canBlock && (rs == EAI_NONAME || rs == EAI_NODATA))
#else
    if(!canBlock && rs == EAI_NONAME)
#endif
    {
        return result; // Empty result indicates that a canBlock lookup is necessary.
    }
    else if(rs != 0)
    {
        throw DNSException(__FILE__, __LINE__, rs, host);
    }

    for(struct addrinfo* p = info; p != ICE_NULLPTR; p = p->ai_next)
    {
        memcpy(&addr.saStorage, p->ai_addr, p->ai_addrlen);
        if(p->ai_family == PF_INET)
        {
            addr.saIn.sin_port = htons(port);
        }
        else if(p->ai_family == PF_INET6)
        {
            addr.saIn6.sin6_port = htons(port);
        }

        bool found = false;
        for(unsigned int i = 0; i < result.size(); ++i)
        {
            if(compareAddress(result[i], addr) == 0)
            {
                found = true;
                break;
            }
        }
        if(!found)
        {
            result.push_back(addr);
        }
    }

    freeaddrinfo(info);

    if(result.empty())
    {
        throw DNSException(__FILE__, __LINE__, 0, host);
    }
    sortAddresses(result, protocol, selType, preferIPv6);
    return result;
}

ProtocolSupport
IceInternal::getProtocolSupport(const Address& addr)
{
    return addr.saStorage.ss_family == AF_INET ? EnableIPv4 : EnableIPv6;
}

Address
IceInternal::getAddressForServer(const string& host, int port, ProtocolSupport protocol, bool preferIPv6, bool canBlock)
{
    //
    // We don't use getaddrinfo when host is empty as it's not portable (some old Linux
    // versions don't support it).
    //
    if(host.empty())
    {
        Address addr;
        memset(&addr.saStorage, 0, sizeof(sockaddr_storage));
        if(protocol != EnableIPv4)
        {
            addr.saIn6.sin6_family = AF_INET6;
            addr.saIn6.sin6_port = htons(port);
            addr.saIn6.sin6_addr = in6addr_any;
        }
        else
        {
            addr.saIn.sin_family = AF_INET;
            addr.saIn.sin_port = htons(port);
            addr.saIn.sin_addr.s_addr = htonl(INADDR_ANY);
        }
        return addr;
    }
    vector<Address> addrs = getAddresses(host, port, protocol, Ice::ICE_ENUM(EndpointSelectionType, Ordered),
                                         preferIPv6, canBlock);
    return addrs.empty() ? Address() : addrs[0];
}

int
IceInternal::compareAddress(const Address& addr1, const Address& addr2)
{
    if(addr1.saStorage.ss_family < addr2.saStorage.ss_family)
    {
        return -1;
    }
    else if(addr2.saStorage.ss_family < addr1.saStorage.ss_family)
    {
        return 1;
    }

    if(addr1.saStorage.ss_family == AF_INET)
    {
        if(addr1.saIn.sin_port < addr2.saIn.sin_port)
        {
            return -1;
        }
        else if(addr2.saIn.sin_port < addr1.saIn.sin_port)
        {
            return 1;
        }

        if(addr1.saIn.sin_addr.s_addr < addr2.saIn.sin_addr.s_addr)
        {
            return -1;
        }
        else if(addr2.saIn.sin_addr.s_addr < addr1.saIn.sin_addr.s_addr)
        {
            return 1;
        }
    }
    else
    {
        if(addr1.saIn6.sin6_port < addr2.saIn6.sin6_port)
        {
            return -1;
        }
        else if(addr2.saIn6.sin6_port < addr1.saIn6.sin6_port)
        {
            return 1;
        }

        int res = memcmp(&addr1.saIn6.sin6_addr, &addr2.saIn6.sin6_addr, sizeof(in6_addr));
        if(res < 0)
        {
            return -1;
        }
        else if(res > 0)
        {
            return 1;
        }
    }

    return 0;
}

bool
IceInternal::isIPv6Supported()
{
    SOCKET fd = socket(AF_INET6, SOCK_STREAM, IPPROTO_TCP);
    if(fd == INVALID_SOCKET)
    {
        return false;
    }
    else
    {
        closeSocketNoThrow(fd);
        return true;
    }
}

SOCKET
IceInternal::createSocket(bool udp, const Address& addr)
{
    return createSocketImpl(udp, addr.saStorage.ss_family);
}
SOCKET
IceInternal::createServerSocket(bool udp, const Address& addr, ProtocolSupport protocol)
{
    SOCKET fd = createSocket(udp, addr);
    if(addr.saStorage.ss_family == AF_INET6 && protocol != EnableIPv4)
    {
        int flag = protocol == EnableIPv6 ? 1 : 0;
        if(setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, reinterpret_cast<char*>(&flag), int(sizeof(int))) == SOCKET_ERROR)
        {
#ifdef _WIN32
            if(getSocketErrno() == WSAENOPROTOOPT)
            {
                return fd; // Windows XP doesn't support IPV6_V6ONLY
            }
#endif
            closeSocketNoThrow(fd);
            throw SocketException(__FILE__, __LINE__, getSocketErrno());
        }
    }
    return fd;
}

void
IceInternal::closeSocketNoThrow(SOCKET fd)
{
#if defined(_WIN32)
    int error = WSAGetLastError();
    closesocket(fd);
    WSASetLastError(error);
#else
    int error = errno;
    close(fd);
    errno = error;
#endif
}

void
IceInternal::closeSocket(SOCKET fd)
{
#if defined(_WIN32)
    int error = WSAGetLastError();
    if(closesocket(fd) == SOCKET_ERROR)
    {
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }
    WSASetLastError(error);
#else
    int error = errno;

#  if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
    //
    // FreeBSD returns ECONNRESET if the underlying object was
    // a stream socket that was shut down by the peer before all
    // pending data was delivered.
    //
    if(close(fd) == SOCKET_ERROR && getSocketErrno() != ECONNRESET)
#  else
    if(close(fd) == SOCKET_ERROR)
#  endif
    {
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }
    errno = error;
#endif
}

string
IceInternal::addrToString(const Address& addr)
{
    ostringstream s;
    s << inetAddrToString(addr) << ':' << getPort(addr);
    return s.str();
}

void
IceInternal::fdToLocalAddress(SOCKET fd, Address& addr)
{
    socklen_t len = static_cast<socklen_t>(sizeof(sockaddr_storage));
    if(getsockname(fd, &addr.sa, &len) == SOCKET_ERROR)
    {
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }
}

bool
IceInternal::fdToRemoteAddress(SOCKET fd, Address& addr)
{
    socklen_t len = static_cast<socklen_t>(sizeof(sockaddr_storage));
    if(getpeername(fd, &addr.sa, &len) == SOCKET_ERROR)
    {
        if(notConnected())
        {
            return false;
        }
        else
        {
            throw SocketException(__FILE__, __LINE__, getSocketErrno());
        }
    }
    return true;
}

std::string
IceInternal::fdToString(SOCKET fd, const NetworkProxyPtr& proxy, const Address& target)
{
    if(fd == INVALID_SOCKET)
    {
        return "<closed>";
    }

    ostringstream s;

    Address remoteAddr;
    bool peerConnected = fdToRemoteAddress(fd, remoteAddr);

#ifdef _WIN32
    if(!peerConnected)
    {
        //
        // The local address is only accessible with connected sockets on Windows.
        //
        s << "local address = <not available>";
    }
    else
#endif
    {
        Address localAddr;
        fdToLocalAddress(fd, localAddr);
        s << "local address = " << addrToString(localAddr);
    }

    if(proxy)
    {
        if(!peerConnected)
        {
            remoteAddr = proxy->getAddress();
        }
        s << "\n" + proxy->getName() + " proxy address = " << addrToString(remoteAddr);
        s << "\nremote address = " << addrToString(target);
    }
    else
    {
        if(!peerConnected)
        {
            remoteAddr = target;
        }
        s << "\nremote address = " << addrToString(remoteAddr);
    }

    return s.str();
}

std::string
IceInternal::fdToString(SOCKET fd)
{
    if(fd == INVALID_SOCKET)
    {
        return "<closed>";
    }

    Address localAddr;
    fdToLocalAddress(fd, localAddr);

    Address remoteAddr;
    bool peerConnected = fdToRemoteAddress(fd, remoteAddr);

    return addressesToString(localAddr, remoteAddr, peerConnected);
}

void
IceInternal::fdToAddressAndPort(SOCKET fd, string& localAddress, int& localPort, string& remoteAddress, int& remotePort)
{
    if(fd == INVALID_SOCKET)
    {
        localAddress.clear();
        remoteAddress.clear();
        localPort = -1;
        remotePort = -1;
        return;
    }

    Address localAddr;
    fdToLocalAddress(fd, localAddr);
    addrToAddressAndPort(localAddr, localAddress, localPort);

    Address remoteAddr;
    if(fdToRemoteAddress(fd, remoteAddr))
    {
        addrToAddressAndPort(remoteAddr, remoteAddress, remotePort);
    }
    else
    {
        remoteAddress.clear();
        remotePort = -1;
    }
}

void
IceInternal::addrToAddressAndPort(const Address& addr, string& address, int& port)
{
    address = inetAddrToString(addr);
    port = getPort(addr);
}

std::string
IceInternal::addressesToString(const Address& localAddr, const Address& remoteAddr, bool peerConnected)
{
    ostringstream s;
    s << "local address = " << addrToString(localAddr);
    if(peerConnected)
    {
        s << "\nremote address = " << addrToString(remoteAddr);
    }
    else
    {
        s << "\nremote address = <not connected>";
    }
    return s.str();
}

bool
IceInternal::isAddressValid(const Address& addr)
{
    return addr.saStorage.ss_family != AF_UNSPEC;
}

vector<string>
IceInternal::getHostsForEndpointExpand(const string& host, ProtocolSupport protocolSupport, bool includeLoopback)
{
    vector<string> hosts;
    bool ipv4Wildcard = false;
    if(isWildcard(host, protocolSupport, ipv4Wildcard))
    {
        vector<Address> addrs = getLocalAddresses(ipv4Wildcard ? EnableIPv4 : protocolSupport, includeLoopback, false);
        for(vector<Address>::const_iterator p = addrs.begin(); p != addrs.end(); ++p)
        {
            //
            // NOTE: We don't publish link-local addresses as in most cases
            //       these are not desired to be published and in some cases
            //       will not work without extra configuration.
            //
            if(!isLinklocal(*p))
            {
                hosts.push_back(inetAddrToString(*p));
            }
        }
        if(hosts.empty())
        {
            // Return loopback if no other local addresses are available.
            addrs = getLoopbackAddresses(protocolSupport);
            for(vector<Address>::const_iterator p = addrs.begin(); p != addrs.end(); ++p)
            {
                hosts.push_back(inetAddrToString(*p));
            }
        }
    }
    return hosts; // An empty host list indicates to just use the given host.
}

vector<string>
IceInternal::getInterfacesForMulticast(const string& intf, ProtocolSupport protocolSupport)
{
    vector<string> interfaces;
    bool ipv4Wildcard = false;
    if(isWildcard(intf, protocolSupport, ipv4Wildcard))
    {
        vector<Address> addrs = getLocalAddresses(ipv4Wildcard ? EnableIPv4 : protocolSupport, true, true);
        for(vector<Address>::const_iterator p = addrs.begin(); p != addrs.end(); ++p)
        {
            interfaces.push_back(inetAddrToString(*p)); // We keep link local addresses for multicast
        }
    }
    if(interfaces.empty())
    {
        interfaces.push_back(intf);
    }
    return interfaces;
}

string
IceInternal::inetAddrToString(const Address& ss)
{
    int size = getAddressStorageSize(ss);
    if(size == 0)
    {
        return "";
    }

    char namebuf[1024];
    namebuf[0] = '\0';
    getnameinfo(&ss.sa, static_cast<socklen_t>(size), namebuf, static_cast<socklen_t>(sizeof(namebuf)), 0, 0,
                NI_NUMERICHOST);
    return string(namebuf);
}

int
IceInternal::getPort(const Address& addr)
{
    if(addr.saStorage.ss_family == AF_INET)
    {
        return ntohs(addr.saIn.sin_port);
    }
    else if(addr.saStorage.ss_family == AF_INET6)
    {
        return ntohs(addr.saIn6.sin6_port);
    }
    else
    {
        return -1;
    }
}

void
IceInternal::setPort(Address& addr, int port)
{
    if(addr.saStorage.ss_family == AF_INET)
    {
        addr.saIn.sin_port = htons(port);
    }
    else
    {
        assert(addr.saStorage.ss_family == AF_INET6);
        addr.saIn6.sin6_port = htons(port);
    }
}

bool
IceInternal::isMulticast(const Address& addr)
{
    if(addr.saStorage.ss_family == AF_INET)
    {
        return IN_MULTICAST(ntohl(addr.saIn.sin_addr.s_addr));
    }
    else if(addr.saStorage.ss_family == AF_INET6)
    {
        return IN6_IS_ADDR_MULTICAST(&addr.saIn6.sin6_addr);
    }
    return false;
}

void
IceInternal::setTcpBufSize(SOCKET fd, const ProtocolInstancePtr& instance)
{
    assert(fd != INVALID_SOCKET);

    //
    // By default, on Windows we use a 128KB buffer size. On Unix
    // platforms, we use the system defaults.
    //
#ifdef _WIN32
    const int dfltBufSize = 128 * 1024;
#else
    const int dfltBufSize = 0;
#endif
    Int rcvSize = instance->properties()->getPropertyAsIntWithDefault("Ice.TCP.RcvSize", dfltBufSize);
    Int sndSize = instance->properties()->getPropertyAsIntWithDefault("Ice.TCP.SndSize", dfltBufSize);

    setTcpBufSize(fd, rcvSize, sndSize, instance);
}

void
IceInternal::setTcpBufSize(SOCKET fd, int rcvSize, int sndSize, const ProtocolInstancePtr& instance)
{
    assert(fd != INVALID_SOCKET);

    if(rcvSize > 0)
    {
        //
        // Try to set the buffer size. The kernel will silently adjust
        // the size to an acceptable value. Then read the size back to
        // get the size that was actually set.
        //
        setRecvBufferSize(fd, rcvSize);
        int size = getRecvBufferSize(fd);
        if(size > 0 && size < rcvSize)
        {
            // Warn if the size that was set is less than the requested size and
            // we have not already warned.
            BufSizeWarnInfo winfo = instance->getBufSizeWarn(TCPEndpointType);
            if(!winfo.rcvWarn || rcvSize != winfo.rcvSize)
            {
                Ice::Warning out(instance->logger());
                out << "TCP receive buffer size: requested size of " << rcvSize << " adjusted to " << size;
                instance->setRcvBufSizeWarn(TCPEndpointType, rcvSize);
            }
        }
    }

    if(sndSize > 0)
    {
        //
        // Try to set the buffer size. The kernel will silently adjust
        // the size to an acceptable value. Then read the size back to
        // get the size that was actually set.
        //
        setSendBufferSize(fd, sndSize);
        int size = getSendBufferSize(fd);
        if(size > 0 && size < sndSize)
        {
            // Warn if the size that was set is less than the requested size and
            // we have not already warned.
            BufSizeWarnInfo winfo = instance->getBufSizeWarn(TCPEndpointType);
            if(!winfo.sndWarn || sndSize != winfo.sndSize)
            {
                Ice::Warning out(instance->logger());
                out << "TCP send buffer size: requested size of " << sndSize << " adjusted to " << size;
                instance->setSndBufSizeWarn(TCPEndpointType, sndSize);
            }
        }
    }
}

void
IceInternal::setBlock(SOCKET fd, bool block)
{
#ifdef _WIN32
    if(block)
    {
        unsigned long arg = 0;
        if(ioctlsocket(fd, FIONBIO, &arg) == SOCKET_ERROR)
        {
            closeSocketNoThrow(fd);
            throw SocketException(__FILE__, __LINE__, WSAGetLastError());
        }
    }
    else
    {
        unsigned long arg = 1;
        if(ioctlsocket(fd, FIONBIO, &arg) == SOCKET_ERROR)
        {
            closeSocketNoThrow(fd);
            throw SocketException(__FILE__, __LINE__, WSAGetLastError());
        }
    }
#else
    if(block)
    {
        int flags = fcntl(fd, F_GETFL);
        flags &= ~O_NONBLOCK;
        if(fcntl(fd, F_SETFL, flags) == SOCKET_ERROR)
        {
            closeSocketNoThrow(fd);
            throw SocketException(__FILE__, __LINE__, errno);
        }
    }
    else
    {
        int flags = fcntl(fd, F_GETFL);
        flags |= O_NONBLOCK;
        if(fcntl(fd, F_SETFL, flags) == SOCKET_ERROR)
        {
            closeSocketNoThrow(fd);
            throw SocketException(__FILE__, __LINE__, errno);
        }
    }
#endif
}

void
IceInternal::setSendBufferSize(SOCKET fd, int sz)
{
    if(setsockopt(fd, SOL_SOCKET, SO_SNDBUF, reinterpret_cast<char*>(&sz), int(sizeof(int))) == SOCKET_ERROR)
    {
        closeSocketNoThrow(fd);
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }
}

int
IceInternal::getSendBufferSize(SOCKET fd)
{
    int sz;
    socklen_t len = sizeof(sz);
    if(getsockopt(fd, SOL_SOCKET, SO_SNDBUF, reinterpret_cast<char*>(&sz), &len) == SOCKET_ERROR ||
       static_cast<unsigned int>(len) != sizeof(sz))
    {
        closeSocketNoThrow(fd);
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }
    return sz;
}

void
IceInternal::setRecvBufferSize(SOCKET fd, int sz)
{
    if(setsockopt(fd, SOL_SOCKET, SO_RCVBUF, reinterpret_cast<char*>(&sz), int(sizeof(int))) == SOCKET_ERROR)
    {
        closeSocketNoThrow(fd);
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }
}

int
IceInternal::getRecvBufferSize(SOCKET fd)
{
    int sz;
    socklen_t len = sizeof(sz);
    if(getsockopt(fd, SOL_SOCKET, SO_RCVBUF, reinterpret_cast<char*>(&sz), &len) == SOCKET_ERROR ||
       static_cast<unsigned int>(len) != sizeof(sz))
    {
        closeSocketNoThrow(fd);
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }
    return sz;
}

void
IceInternal::setMcastGroup(SOCKET fd, const Address& group, const string& intf)
{
    vector<string> interfaces = getInterfacesForMulticast(intf, getProtocolSupport(group));
    set<int> indexes;
    for(vector<string>::const_iterator p = interfaces.begin(); p != interfaces.end(); ++p)
    {
        int rc = 0;
        if(group.saStorage.ss_family == AF_INET)
        {
            struct ip_mreq mreq;
            mreq.imr_multiaddr = group.saIn.sin_addr;
            mreq.imr_interface = getInterfaceAddress(*p);
            rc = setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, reinterpret_cast<char*>(&mreq), int(sizeof(mreq)));
        }
        else
        {
            int index = getInterfaceIndex(*p);
            if(indexes.find(index) == indexes.end()) // Don't join twice the same interface (if it has multiple IPs)
            {
                indexes.insert(index);
                struct ipv6_mreq mreq;
                mreq.ipv6mr_multiaddr = group.saIn6.sin6_addr;
                mreq.ipv6mr_interface = static_cast<unsigned int>(index);
                rc = setsockopt(fd, IPPROTO_IPV6, IPV6_JOIN_GROUP, reinterpret_cast<char*>(&mreq), int(sizeof(mreq)));
            }
        }
        if(rc == SOCKET_ERROR)
        {
            closeSocketNoThrow(fd);
            throw SocketException(__FILE__, __LINE__, getSocketErrno());
        }
    }
}

void
IceInternal::setMcastInterface(SOCKET fd, const string& intf, const Address& addr)
{
    int rc;
    if(addr.saStorage.ss_family == AF_INET)
    {
        struct in_addr iface = getInterfaceAddress(intf);
        rc = setsockopt(fd, IPPROTO_IP, IP_MULTICAST_IF, reinterpret_cast<char*>(&iface), int(sizeof(iface)));
    }
    else
    {
        int interfaceNum = getInterfaceIndex(intf);
        rc = setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_IF, reinterpret_cast<char*>(&interfaceNum), int(sizeof(int)));
    }
    if(rc == SOCKET_ERROR)
    {
        closeSocketNoThrow(fd);
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }
}

void
IceInternal::setMcastTtl(SOCKET fd, int ttl, const Address& addr)
{
    int rc;
    if(addr.saStorage.ss_family == AF_INET)
    {
        rc = setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL, reinterpret_cast<char*>(&ttl), int(sizeof(int)));
    }
    else
    {
        rc = setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, reinterpret_cast<char*>(&ttl), int(sizeof(int)));
    }
    if(rc == SOCKET_ERROR)
    {
        closeSocketNoThrow(fd);
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }
}

void
IceInternal::setReuseAddress(SOCKET fd, bool reuse)
{
    int flag = reuse ? 1 : 0;
    if(setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, reinterpret_cast<char*>(&flag), int(sizeof(int))) == SOCKET_ERROR)
    {
        closeSocketNoThrow(fd);
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }
}

Address
IceInternal::doBind(SOCKET fd, const Address& addr, const string&)
{
    int size = getAddressStorageSize(addr);
    assert(size != 0);

    if(::bind(fd, &addr.sa, static_cast<socklen_t>(size)) == SOCKET_ERROR)
    {
        closeSocketNoThrow(fd);
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }

    Address local;
    socklen_t len = static_cast<socklen_t>(sizeof(sockaddr_storage));
#ifdef NDEBUG
    getsockname(fd, &local.sa, &len);
#else
    int ret = getsockname(fd, &local.sa, &len);
    assert(ret != SOCKET_ERROR);
#endif
    return local;
}

Address
IceInternal::getNumericAddress(const std::string& address)
{
    vector<Address> addrs = getAddresses(address, 0, EnableBoth, Ice::ICE_ENUM(EndpointSelectionType, Ordered), false,
                                         false);
    if(addrs.empty())
    {
        return Address();
    }
    else
    {
        return addrs[0];
    }
}

int
IceInternal::getSocketErrno()
{
#if defined(_WIN32)
    return WSAGetLastError();
#else
    return errno;
#endif
}

bool
IceInternal::interrupted()
{
#ifdef _WIN32
    return WSAGetLastError() == WSAEINTR;
#else
#   ifdef EPROTO
    return errno == EINTR || errno == EPROTO;
#   else
    return errno == EINTR;
#   endif
#endif
}

bool
IceInternal::acceptInterrupted()
{
    if(interrupted())
    {
        return true;
    }

#ifdef _WIN32
    int error = WSAGetLastError();
    return error == WSAECONNABORTED ||
           error == WSAECONNRESET ||
           error == WSAETIMEDOUT;
#else
    return errno == ECONNABORTED ||
           errno == ECONNRESET ||
           errno == ETIMEDOUT;
#endif
}

bool
IceInternal::noBuffers()
{
#ifdef _WIN32
    int error = WSAGetLastError();
    return error == WSAENOBUFS ||
           error == WSAEFAULT;
#else
    return errno == ENOBUFS;
#endif
}

bool
IceInternal::wouldBlock()
{
#ifdef _WIN32
    int error = WSAGetLastError();
    return error == WSAEWOULDBLOCK || error == WSA_IO_PENDING || error == ERROR_IO_PENDING;
#else
    return errno == EAGAIN || errno == EWOULDBLOCK;
#endif
}

bool
IceInternal::connectFailed()
{
#if defined(_WIN32)
    int error = WSAGetLastError();
    return error == WSAECONNREFUSED ||
           error == WSAETIMEDOUT ||
           error == WSAENETUNREACH ||
           error == WSAEHOSTUNREACH ||
           error == WSAECONNRESET ||
           error == WSAESHUTDOWN ||
           error == WSAECONNABORTED ||
           error == ERROR_SEM_TIMEOUT ||
           error == ERROR_NETNAME_DELETED;
#else
    return errno == ECONNREFUSED ||
           errno == ETIMEDOUT ||
           errno == ENETUNREACH ||
           errno == EHOSTUNREACH ||
           errno == ECONNRESET ||
           errno == ESHUTDOWN ||
           errno == ECONNABORTED;
#endif
}

bool
IceInternal::connectionRefused()
{
#if defined(_WIN32)
    int error = WSAGetLastError();
    return error == WSAECONNREFUSED || error == ERROR_CONNECTION_REFUSED;
#else
    return errno == ECONNREFUSED;
#endif
}

bool
IceInternal::connectionLost()
{
#ifdef _WIN32
    int error = WSAGetLastError();
    return error == WSAECONNRESET ||
           error == WSAESHUTDOWN ||
           error == WSAENOTCONN ||
#   ifdef ICE_USE_IOCP
           error == ERROR_NETNAME_DELETED ||
#   endif
           error == WSAECONNABORTED;
#else
    return errno == ECONNRESET ||
           errno == ENOTCONN ||
           errno == ESHUTDOWN ||
           errno == ECONNABORTED ||
           errno == EPIPE;
#endif
}

bool
IceInternal::connectInProgress()
{
#ifdef _WIN32
    int error = WSAGetLastError();
    return error == WSAEWOULDBLOCK || error == WSA_IO_PENDING || error == ERROR_IO_PENDING;
#else
    return errno == EINPROGRESS;
#endif
}

bool
IceInternal::notConnected()
{
#ifdef _WIN32
    return WSAGetLastError() == WSAENOTCONN;
#elif defined(__APPLE__) || defined(__FreeBSD__)
    return errno == ENOTCONN || errno == EINVAL;
#else
    return errno == ENOTCONN;
#endif
}

bool
IceInternal::recvTruncated()
{
#ifdef _WIN32
    int err = WSAGetLastError();
    return err == WSAEMSGSIZE || err == ERROR_MORE_DATA;
#else
    // We don't get an error under Linux if a datagram is truncated.
    return false;
#endif
}

void
IceInternal::doListen(SOCKET fd, int backlog)
{
repeatListen:
    if(::listen(fd, backlog) == SOCKET_ERROR)
    {
        if(interrupted())
        {
            goto repeatListen;
        }

        closeSocketNoThrow(fd);
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }
}

bool
IceInternal::doConnect(SOCKET fd, const Address& addr, const Address& sourceAddr)
{
    if(isAddressValid(sourceAddr))
    {
        doBind(fd, sourceAddr);
    }

repeatConnect:
    int size = getAddressStorageSize(addr);
    assert(size != 0);

    if(::connect(fd, &addr.sa, static_cast<socklen_t>(size)) == SOCKET_ERROR)
    {
        if(interrupted())
        {
            goto repeatConnect;
        }

        if(connectInProgress())
        {
            return false;
        }

        closeSocketNoThrow(fd);
        if(connectionRefused())
        {
            throw ConnectionRefusedException(__FILE__, __LINE__, getSocketErrno());
        }
        else if(connectFailed())
        {
            throw ConnectFailedException(__FILE__, __LINE__, getSocketErrno());
        }
        else
        {
            throw SocketException(__FILE__, __LINE__, getSocketErrno());
        }
    }

#if defined(__linux__)
    //
    // Prevent self connect (self connect happens on Linux when a client tries to connect to
    // a server which was just deactivated if the client socket re-uses the same ephemeral
    // port as the server).
    //
    Address localAddr;
    try
    {
        fdToLocalAddress(fd, localAddr);
        if(compareAddress(addr, localAddr) == 0)
        {
            throw ConnectionRefusedException(__FILE__, __LINE__, 0); // No appropriate errno
        }
    }
    catch(const LocalException&)
    {
        closeSocketNoThrow(fd);
        throw;
    }
#endif
    return true;
}

void
IceInternal::doFinishConnect(SOCKET fd)
{
    //
    // Note: we don't close the socket if there's an exception. It's the responsability
    // of the caller to do so.
    //

    //
    // Strange windows bug: The following call to Sleep() is
    // necessary, otherwise no error is reported through
    // getsockopt.
    //
#if defined(_WIN32)
    Sleep(0);
#endif

    int val;
    socklen_t len = static_cast<socklen_t>(sizeof(int));
    if(getsockopt(fd, SOL_SOCKET, SO_ERROR, reinterpret_cast<char*>(&val), &len) == SOCKET_ERROR)
    {
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }

    if(val > 0)
    {
#if defined(_WIN32)
        WSASetLastError(val);
#else
        errno = val;
#endif
        if(connectionRefused())
        {
            throw ConnectionRefusedException(__FILE__, __LINE__, getSocketErrno());
        }
        else if(connectFailed())
        {
            throw ConnectFailedException(__FILE__, __LINE__, getSocketErrno());
        }
        else
        {
            throw SocketException(__FILE__, __LINE__, getSocketErrno());
        }
    }

#if defined(__linux__)
    //
    // Prevent self connect (self connect happens on Linux when a client tries to connect to
    // a server which was just deactivated if the client socket re-uses the same ephemeral
    // port as the server).
    //
    Address localAddr;
    fdToLocalAddress(fd, localAddr);
    Address remoteAddr;
    if(fdToRemoteAddress(fd, remoteAddr) && compareAddress(remoteAddr, localAddr) == 0)
    {
        throw ConnectionRefusedException(__FILE__, __LINE__, 0); // No appropriate errno
    }
#endif
}

SOCKET
IceInternal::doAccept(SOCKET fd)
{
#ifdef _WIN32
    SOCKET ret;
#else
    int ret;
#endif

repeatAccept:
    if((ret = ::accept(fd, 0, 0)) == INVALID_SOCKET)
    {
        if(acceptInterrupted())
        {
            goto repeatAccept;
        }

        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }

    setTcpNoDelay(ret);
    setKeepAlive(ret);
    return ret;
}

void
IceInternal::createPipe(SOCKET fds[2])
{
#ifdef _WIN32

    SOCKET fd = createSocketImpl(false, AF_INET);
    setBlock(fd, true);

    Address addr;
    memset(&addr.saStorage, 0, sizeof(sockaddr_storage));

    addr.saIn.sin_family = AF_INET;
    addr.saIn.sin_port = htons(0);
    addr.saIn.sin_addr.s_addr = htonl(INADDR_LOOPBACK);

    addr = doBind(fd, addr);
    doListen(fd, 1);

    try
    {
        fds[0] = createSocketImpl(false, AF_INET);
    }
    catch(...)
    {
        ::closesocket(fd);
        throw;
    }

    try
    {
        setBlock(fds[0], true);
#  ifndef NDEBUG
        bool connected = doConnect(fds[0], addr, Address());
        assert(connected);
#  else
        doConnect(fds[0], addr, Address());
#  endif
    }
    catch(...)
    {
        // fds[0] is closed by doConnect
        ::closesocket(fd);
        throw;
    }

    try
    {
        fds[1] = doAccept(fd);
    }
    catch(...)
    {
        ::closesocket(fds[0]);
        ::closesocket(fd);
        throw;
    }

    ::closesocket(fd);

    try
    {
        setBlock(fds[1], true);
    }
    catch(...)
    {
        ::closesocket(fds[0]);
        // fds[1] is closed by setBlock
        throw;
    }

#else

    if(::pipe(fds) != 0)
    {
        throw SyscallException(__FILE__, __LINE__, getSocketErrno());
    }

    try
    {
        setBlock(fds[0], true);
    }
    catch(...)
    {
        // fds[0] is closed by setBlock
        closeSocketNoThrow(fds[1]);
        throw;
    }

    try
    {
        setBlock(fds[1], true);
    }
    catch(...)
    {
        closeSocketNoThrow(fds[0]);
        // fds[1] is closed by setBlock
        throw;
    }

#endif
}

#if defined(ICE_USE_IOCP)
void
IceInternal::doConnectAsync(SOCKET fd, const Address& addr, const Address& sourceAddr, AsyncInfo& info)
{
    //
    // NOTE: It's the caller's responsability to close the socket upon
    // failure to connect. The socket isn't closed by this method.
    //
    Address bindAddr;
    if(isAddressValid(sourceAddr))
    {
        bindAddr = sourceAddr;
    }
    else
    {
        memset(&bindAddr.saStorage, 0, sizeof(sockaddr_storage));
        if(addr.saStorage.ss_family == AF_INET)
        {
            bindAddr.saIn.sin_family = AF_INET;
            bindAddr.saIn.sin_port = htons(0);
            bindAddr.saIn.sin_addr.s_addr = htonl(INADDR_ANY);
        }
        else if(addr.saStorage.ss_family == AF_INET6)
        {
            bindAddr.saIn6.sin6_family = AF_INET6;
            bindAddr.saIn6.sin6_port = htons(0);
            bindAddr.saIn6.sin6_addr = in6addr_any;
        }
    }

    int size = getAddressStorageSize(bindAddr);
    assert(size != 0);

    if(::bind(fd, &bindAddr.sa, size) == SOCKET_ERROR)
    {
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }

    LPFN_CONNECTEX ConnectEx = ICE_NULLPTR; // a pointer to the 'ConnectEx()' function
    GUID GuidConnectEx = WSAID_CONNECTEX; // The Guid
    DWORD dwBytes;
    if(WSAIoctl(fd,
                SIO_GET_EXTENSION_FUNCTION_POINTER,
                &GuidConnectEx,
                sizeof(GuidConnectEx),
                &ConnectEx,
                sizeof(ConnectEx),
                &dwBytes,
                ICE_NULLPTR,
                ICE_NULLPTR) == SOCKET_ERROR)
    {
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }

    if(!ConnectEx(fd, &addr.sa, size, 0, 0, 0, &info))
    {
        if(!connectInProgress())
        {
            if(connectionRefused())
            {
                throw ConnectionRefusedException(__FILE__, __LINE__, getSocketErrno());
            }
            else if(connectFailed())
            {
                throw ConnectFailedException(__FILE__, __LINE__, getSocketErrno());
            }
            else
            {
                throw SocketException(__FILE__, __LINE__, getSocketErrno());
            }
        }
    }
}

void
IceInternal::doFinishConnectAsync(SOCKET fd, AsyncInfo& info)
{
    //
    // NOTE: It's the caller's responsability to close the socket upon
    // failure to connect. The socket isn't closed by this method.
    //

    if(info.error != ERROR_SUCCESS)
    {
        WSASetLastError(info.error);
        if(connectionRefused())
        {
            throw ConnectionRefusedException(__FILE__, __LINE__, getSocketErrno());
        }
        else if(connectFailed())
        {
            throw ConnectFailedException(__FILE__, __LINE__, getSocketErrno());
        }
        else
        {
            throw SocketException(__FILE__, __LINE__, getSocketErrno());
        }
    }

    if(setsockopt(fd, SOL_SOCKET, SO_UPDATE_CONNECT_CONTEXT, ICE_NULLPTR, 0) == SOCKET_ERROR)
    {
        throw SocketException(__FILE__, __LINE__, getSocketErrno());
    }
}
#endif

bool
IceInternal::isIpAddress(const string& name)
{
    in_addr addr;
    in6_addr addr6;

    return inet_pton(AF_INET, name.c_str(), &addr) > 0 || inet_pton(AF_INET6, name.c_str(), &addr6) > 0;
}