CArchNetworkBSD.cpp

/*
 * synergy -- mouse and keyboard sharing utility
 * Copyright (C) 2012 Bolton Software Ltd.
 * Copyright (C) 2002 Chris Schoeneman
 * 
 * This package is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * found in the file COPYING that should have accompanied this file.
 * 
 * This package is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "CArchNetworkBSD.h"
#include "CArch.h"
#include "CArchMultithreadPosix.h"
#include "XArchUnix.h"
#if HAVE_UNISTD_H
#   include <unistd.h>
#endif
#include <netinet/in.h>
#include <netdb.h>
#if !defined(TCP_NODELAY)
#   include <netinet/tcp.h>
#endif
#include <arpa/inet.h>
#include <fcntl.h>
#include <errno.h>
#include <string.h>

#if HAVE_POLL
#   include <poll.h>
#else
#   if HAVE_SYS_SELECT_H
#       include <sys/select.h>
#   endif
#   if HAVE_SYS_TIME_H
#       include <sys/time.h>
#   endif
#endif

#if !HAVE_INET_ATON
#   include <stdio.h>
#endif

static const int s_family[] = {
    PF_UNSPEC,
    PF_INET
};
static const int s_type[] = {
    SOCK_DGRAM,
    SOCK_STREAM
};

#if !HAVE_INET_ATON
// parse dotted quad addresses.  we don't bother with the weird BSD'ism
// of handling octal and hex and partial forms.
static
in_addr_t
inet_aton(const char* cp, struct in_addr* inp)
{
    unsigned int a, b, c, d;
    if (sscanf(cp, "%u.%u.%u.%u", &a, &b, &c, &d) != 4) {
        return 0;
    }
    if (a >= 256 || b >= 256 || c >= 256 || d >= 256) {
        return 0;
    }
    unsigned char* incp = (unsigned char*)inp;
    incp[0] = (unsigned char)(a & 0xffu);
    incp[1] = (unsigned char)(b & 0xffu);
    incp[2] = (unsigned char)(c & 0xffu);
    incp[3] = (unsigned char)(d & 0xffu);
    return inp->s_addr;
}
#endif

//
// CArchNetworkBSD
//

CArchNetworkBSD::CArchNetworkBSD()
{
}

CArchNetworkBSD::~CArchNetworkBSD()
{
    ARCH->closeMutex(m_mutex);
}

void
CArchNetworkBSD::init()
{
    // create mutex to make some calls thread safe
    m_mutex = ARCH->newMutex();
}

CArchSocket
CArchNetworkBSD::newSocket(EAddressFamily family, ESocketType type)
{
    // create socket
    int fd = socket(s_family[family], s_type[type], 0);
    if (fd == -1) {
        throwError(errno);
    }
    try {
        setBlockingOnSocket(fd, false);
    }
    catch (...) {
        close(fd);
        throw;
    }

    // allocate socket object
    CArchSocketImpl* newSocket = new CArchSocketImpl;
    newSocket->m_fd            = fd;
    newSocket->m_refCount      = 1;
    return newSocket;
}

CArchSocket
CArchNetworkBSD::copySocket(CArchSocket s)
{
    assert(s != NULL);

    // ref the socket and return it
    ARCH->lockMutex(m_mutex);
    ++s->m_refCount;
    ARCH->unlockMutex(m_mutex);
    return s;
}

void
CArchNetworkBSD::closeSocket(CArchSocket s)
{
    assert(s != NULL);

    // unref the socket and note if it should be released
    ARCH->lockMutex(m_mutex);
    const bool doClose = (--s->m_refCount == 0);
    ARCH->unlockMutex(m_mutex);

    // close the socket if necessary
    if (doClose) {
        if (close(s->m_fd) == -1) {
            // close failed.  restore the last ref and throw.
            int err = errno;
            ARCH->lockMutex(m_mutex);
            ++s->m_refCount;
            ARCH->unlockMutex(m_mutex);
            throwError(err);
        }
        delete s;
    }
}

void
CArchNetworkBSD::closeSocketForRead(CArchSocket s)
{
    assert(s != NULL);

    if (shutdown(s->m_fd, 0) == -1) {
        if (errno != ENOTCONN) {
            throwError(errno);
        }
    }
}

void
CArchNetworkBSD::closeSocketForWrite(CArchSocket s)
{
    assert(s != NULL);

    if (shutdown(s->m_fd, 1) == -1) {
        if (errno != ENOTCONN) {
            throwError(errno);
        }
    }
}

void
CArchNetworkBSD::bindSocket(CArchSocket s, CArchNetAddress addr)
{
    assert(s    != NULL);
    assert(addr != NULL);

    if (bind(s->m_fd, &addr->m_addr, addr->m_len) == -1) {
        throwError(errno);
    }
}

void
CArchNetworkBSD::listenOnSocket(CArchSocket s)
{
    assert(s != NULL);

    // hardcoding backlog
    if (listen(s->m_fd, 3) == -1) {
        throwError(errno);
    }
}

CArchSocket
CArchNetworkBSD::acceptSocket(CArchSocket s, CArchNetAddress* addr)
{
    assert(s != NULL);

    // if user passed NULL in addr then use scratch space
    CArchNetAddress dummy;
    if (addr == NULL) {
        addr = &dummy;
    }

    // create new socket and address
    CArchSocketImpl* newSocket = new CArchSocketImpl;
    *addr                      = new CArchNetAddressImpl;

    // accept on socket
    ACCEPT_TYPE_ARG3 len = (ACCEPT_TYPE_ARG3)((*addr)->m_len);
    int fd = accept(s->m_fd, &(*addr)->m_addr, &len);
    (*addr)->m_len = (socklen_t)len;
    if (fd == -1) {
        int err = errno;
        delete newSocket;
        delete *addr;
        *addr = NULL;
        if (err == EAGAIN) {
            return NULL;
        }
        throwError(err);
    }

    try {
        setBlockingOnSocket(fd, false);
    }
    catch (...) {
        close(fd);
        delete newSocket;
        delete *addr;
        *addr = NULL;
        throw;
    }

    // initialize socket
    newSocket->m_fd       = fd;
    newSocket->m_refCount = 1;

    // discard address if not requested
    if (addr == &dummy) {
        ARCH->closeAddr(dummy);
    }

    return newSocket;
}

bool
CArchNetworkBSD::connectSocket(CArchSocket s, CArchNetAddress addr)
{
    assert(s    != NULL);
    assert(addr != NULL);

    if (connect(s->m_fd, &addr->m_addr, addr->m_len) == -1) {
        if (errno == EISCONN) {
            return true;
        }
        if (errno == EINPROGRESS) {
            return false;
        }
        throwError(errno);
    }
    return true;
}

#if HAVE_POLL

int
CArchNetworkBSD::pollSocket(CPollEntry pe[], int num, double timeout)
{
    assert(pe != NULL || num == 0);

    // return if nothing to do
    if (num == 0) {
        if (timeout > 0.0) {
            ARCH->sleep(timeout);
        }
        return 0;
    }

    // allocate space for translated query
    struct pollfd* pfd = new struct pollfd[1 + num];

    // translate query
    for (int i = 0; i < num; ++i) {
        pfd[i].fd     = (pe[i].m_socket == NULL) ? -1 : pe[i].m_socket->m_fd;
        pfd[i].events = 0;
        if ((pe[i].m_events & kPOLLIN) != 0) {
            pfd[i].events |= POLLIN;
        }
        if ((pe[i].m_events & kPOLLOUT) != 0) {
            pfd[i].events |= POLLOUT;
        }
    }
    int n = num;

    // add the unblock pipe
    const int* unblockPipe = getUnblockPipe();
    if (unblockPipe != NULL) {
        pfd[n].fd     = unblockPipe[0];
        pfd[n].events = POLLIN;
        ++n;
    }

    // prepare timeout
    int t = (timeout < 0.0) ? -1 : static_cast<int>(1000.0 * timeout);

    // do the poll
    n = poll(pfd, n, t);

    // reset the unblock pipe
    if (n > 0 && unblockPipe != NULL && (pfd[num].revents & POLLIN) != 0) {
        // the unblock event was signalled.  flush the pipe.
        char dummy[100];
        int ignore;

        do {
            ignore = read(unblockPipe[0], dummy, sizeof(dummy));
        } while (errno != EAGAIN);

        // don't count this unblock pipe in return value
        --n;
    }

    // handle results
    if (n == -1) {
        if (errno == EINTR) {
            // interrupted system call
            ARCH->testCancelThread();
            delete[] pfd;
            return 0;
        }
        delete[] pfd;
        throwError(errno);
    }

    // translate back
    for (int i = 0; i < num; ++i) {
        pe[i].m_revents = 0;
        if ((pfd[i].revents & POLLIN) != 0) {
            pe[i].m_revents |= kPOLLIN;
        }
        if ((pfd[i].revents & POLLOUT) != 0) {
            pe[i].m_revents |= kPOLLOUT;
        }
        if ((pfd[i].revents & POLLERR) != 0) {
            pe[i].m_revents |= kPOLLERR;
        }
        if ((pfd[i].revents & POLLNVAL) != 0) {
            pe[i].m_revents |= kPOLLNVAL;
        }
    }

    delete[] pfd;
    return n;
}

#else

int
CArchNetworkBSD::pollSocket(CPollEntry pe[], int num, double timeout)
{
    int i, n;

    // prepare sets for select
    n = 0;
    fd_set readSet, writeSet, errSet;
    fd_set* readSetP  = NULL;
    fd_set* writeSetP = NULL;
    fd_set* errSetP   = NULL;
    FD_ZERO(&readSet);
    FD_ZERO(&writeSet);
    FD_ZERO(&errSet);
    for (i = 0; i < num; ++i) {
        // reset return flags
        pe[i].m_revents = 0;

        // set invalid flag if socket is bogus then go to next socket
        if (pe[i].m_socket == NULL) {
            pe[i].m_revents |= kPOLLNVAL;
            continue;
        }

        int fdi = pe[i].m_socket->m_fd;
        if (pe[i].m_events & kPOLLIN) {
            FD_SET(pe[i].m_socket->m_fd, &readSet);
            readSetP = &readSet;
            if (fdi > n) {
                n = fdi;
            }
        }
        if (pe[i].m_events & kPOLLOUT) {
            FD_SET(pe[i].m_socket->m_fd, &writeSet);
            writeSetP = &writeSet;
            if (fdi > n) {
                n = fdi;
            }
        }
        if (true) {
            FD_SET(pe[i].m_socket->m_fd, &errSet);
            errSetP = &errSet;
            if (fdi > n) {
                n = fdi;
            }
        }
    }

    // add the unblock pipe
    const int* unblockPipe = getUnblockPipe();
    if (unblockPipe != NULL) {
        FD_SET(unblockPipe[0], &readSet);
        readSetP = &readSet;
        if (unblockPipe[0] > n) {
            n = unblockPipe[0];
        }
    }

    // if there are no sockets then don't block forever
    if (n == 0 && timeout < 0.0) {
        timeout = 0.0;
    }

    // prepare timeout for select
    struct timeval timeout2;
    struct timeval* timeout2P;
    if (timeout < 0.0) {
        timeout2P = NULL;
    }
    else {
        timeout2P = &timeout2;
        timeout2.tv_sec  = static_cast<int>(timeout);
        timeout2.tv_usec = static_cast<int>(1.0e+6 *
                                        (timeout - timeout2.tv_sec));
    }

    // do the select
    n = select((SELECT_TYPE_ARG1)  n + 1,
                SELECT_TYPE_ARG234 readSetP,
                SELECT_TYPE_ARG234 writeSetP,
                SELECT_TYPE_ARG234 errSetP,
                SELECT_TYPE_ARG5   timeout2P);

    // reset the unblock pipe
    if (n > 0 && unblockPipe != NULL && FD_ISSET(unblockPipe[0], &readSet)) {
        // the unblock event was signalled.  flush the pipe.
        char dummy[100];
        do {
            read(unblockPipe[0], dummy, sizeof(dummy));
        } while (errno != EAGAIN);
    }

    // handle results
    if (n == -1) {
        if (errno == EINTR) {
            // interrupted system call
            ARCH->testCancelThread();
            return 0;
        }
        throwError(errno);
    }
    n = 0;
    for (i = 0; i < num; ++i) {
        if (pe[i].m_socket != NULL) {
            if (FD_ISSET(pe[i].m_socket->m_fd, &readSet)) {
                pe[i].m_revents |= kPOLLIN;
            }
            if (FD_ISSET(pe[i].m_socket->m_fd, &writeSet)) {
                pe[i].m_revents |= kPOLLOUT;
            }
            if (FD_ISSET(pe[i].m_socket->m_fd, &errSet)) {
                pe[i].m_revents |= kPOLLERR;
            }
        }
        if (pe[i].m_revents != 0) {
            ++n;
        }
    }

    return n;
}

#endif

void
CArchNetworkBSD::unblockPollSocket(CArchThread thread)
{
    const int* unblockPipe = getUnblockPipeForThread(thread);
    if (unblockPipe != NULL) {
        char dummy = 0;
        int ignore;

        ignore = write(unblockPipe[1], &dummy, 1);
    }
}

size_t
CArchNetworkBSD::readSocket(CArchSocket s, void* buf, size_t len)
{
    assert(s != NULL);

    ssize_t n = read(s->m_fd, buf, len);
    if (n == -1) {
        if (errno == EINTR || errno == EAGAIN) {
            return 0;
        }
        throwError(errno);
    }
    return n;
}

size_t
CArchNetworkBSD::writeSocket(CArchSocket s, const void* buf, size_t len)
{
    assert(s != NULL);

    ssize_t n = write(s->m_fd, buf, len);
    if (n == -1) {
        if (errno == EINTR || errno == EAGAIN) {
            return 0;
        }
        throwError(errno);
    }
    return n;
}

void
CArchNetworkBSD::throwErrorOnSocket(CArchSocket s)
{
    assert(s != NULL);

    // get the error from the socket layer
    int err        = 0;
    socklen_t size = (socklen_t)sizeof(err);
    if (getsockopt(s->m_fd, SOL_SOCKET, SO_ERROR,
                            (optval_t*)&err, &size) == -1) {
        err = errno;
    }

    // throw if there's an error
    if (err != 0) {
        throwError(err);
    }
}

void
CArchNetworkBSD::setBlockingOnSocket(int fd, bool blocking)
{
    assert(fd != -1);

    int mode = fcntl(fd, F_GETFL, 0);
    if (mode == -1) {
        throwError(errno);
    }
    if (blocking) {
        mode &= ~O_NONBLOCK;
    }
    else {
        mode |= O_NONBLOCK;
    }
    if (fcntl(fd, F_SETFL, mode) == -1) {
        throwError(errno);
    }
}

bool
CArchNetworkBSD::setNoDelayOnSocket(CArchSocket s, bool noDelay)
{
    assert(s != NULL);

    // get old state
    int oflag;
    socklen_t size = (socklen_t)sizeof(oflag);
    if (getsockopt(s->m_fd, IPPROTO_TCP, TCP_NODELAY,
                            (optval_t*)&oflag, &size) == -1) {
        throwError(errno);
    }

    int flag = noDelay ? 1 : 0;
    size     = (socklen_t)sizeof(flag);
    if (setsockopt(s->m_fd, IPPROTO_TCP, TCP_NODELAY,
                            (optval_t*)&flag, size) == -1) {
        throwError(errno);
    }

    return (oflag != 0);
}

bool
CArchNetworkBSD::setReuseAddrOnSocket(CArchSocket s, bool reuse)
{
    assert(s != NULL);

    // get old state
    int oflag;
    socklen_t size = (socklen_t)sizeof(oflag);
    if (getsockopt(s->m_fd, SOL_SOCKET, SO_REUSEADDR,
                            (optval_t*)&oflag, &size) == -1) {
        throwError(errno);
    }

    int flag = reuse ? 1 : 0;
    size     = (socklen_t)sizeof(flag);
    if (setsockopt(s->m_fd, SOL_SOCKET, SO_REUSEADDR,
                            (optval_t*)&flag, size) == -1) {
        throwError(errno);
    }

    return (oflag != 0);
}

std::string
CArchNetworkBSD::getHostName()
{
    char name[256];
    if (gethostname(name, sizeof(name)) == -1) {
        name[0] = '\0';
    }
    else {
        name[sizeof(name) - 1] = '\0';
    }
    return name;
}

CArchNetAddress
CArchNetworkBSD::newAnyAddr(EAddressFamily family)
{
    // allocate address
    CArchNetAddressImpl* addr = new CArchNetAddressImpl;

    // fill it in
    switch (family) {
    case kINET: {
        struct sockaddr_in* ipAddr =
            reinterpret_cast<struct sockaddr_in*>(&addr->m_addr);
        ipAddr->sin_family         = AF_INET;
        ipAddr->sin_port           = 0;
        ipAddr->sin_addr.s_addr    = INADDR_ANY;
        addr->m_len                = (socklen_t)sizeof(struct sockaddr_in);
        break;
    }

    default:
        delete addr;
        assert(0 && "invalid family");
    }

    return addr;
}

CArchNetAddress
CArchNetworkBSD::copyAddr(CArchNetAddress addr)
{
    assert(addr != NULL);

    // allocate and copy address
    return new CArchNetAddressImpl(*addr);
}

CArchNetAddress
CArchNetworkBSD::nameToAddr(const std::string& name)
{
    // allocate address
    CArchNetAddressImpl* addr = new CArchNetAddressImpl;

    // try to convert assuming an IPv4 dot notation address
    struct sockaddr_in inaddr;
    memset(&inaddr, 0, sizeof(inaddr));
    if (inet_aton(name.c_str(), &inaddr.sin_addr) != 0) {
        // it's a dot notation address
        addr->m_len       = (socklen_t)sizeof(struct sockaddr_in);
        inaddr.sin_family = AF_INET;
        inaddr.sin_port   = 0;
        memcpy(&addr->m_addr, &inaddr, addr->m_len);
    }

    else {
        // mutexed address lookup (ugh)
        ARCH->lockMutex(m_mutex);
        struct hostent* info = gethostbyname(name.c_str());
        if (info == NULL) {
            ARCH->unlockMutex(m_mutex);
            delete addr;
            throwNameError(h_errno);
        }

        // copy over address (only IPv4 currently supported)
        if (info->h_addrtype == AF_INET) {
            addr->m_len       = (socklen_t)sizeof(struct sockaddr_in);
            inaddr.sin_family = info->h_addrtype;
            inaddr.sin_port   = 0;
            memcpy(&inaddr.sin_addr, info->h_addr_list[0],
                                sizeof(inaddr.sin_addr));
            memcpy(&addr->m_addr, &inaddr, addr->m_len);
        }
        else {
            ARCH->unlockMutex(m_mutex);
            delete addr;
            throw XArchNetworkNameUnsupported(
                    "The requested name is valid but "
                    "does not have a supported address family");
        }

        // done with static buffer
        ARCH->unlockMutex(m_mutex);
    }

    return addr;
}

void
CArchNetworkBSD::closeAddr(CArchNetAddress addr)
{
    assert(addr != NULL);

    delete addr;
}

std::string
CArchNetworkBSD::addrToName(CArchNetAddress addr)
{
    assert(addr != NULL);

    // mutexed name lookup (ugh)
    ARCH->lockMutex(m_mutex);
    struct hostent* info = gethostbyaddr(
                            reinterpret_cast<const char*>(&addr->m_addr),
                            addr->m_len, addr->m_addr.sa_family);
    if (info == NULL) {
        ARCH->unlockMutex(m_mutex);
        throwNameError(h_errno);
    }

    // save (primary) name
    std::string name = info->h_name;

    // done with static buffer
    ARCH->unlockMutex(m_mutex);

    return name;
}

std::string
CArchNetworkBSD::addrToString(CArchNetAddress addr)
{
    assert(addr != NULL);

    switch (getAddrFamily(addr)) {
    case kINET: {
        struct sockaddr_in* ipAddr =
            reinterpret_cast<struct sockaddr_in*>(&addr->m_addr);
        ARCH->lockMutex(m_mutex);
        std::string s = inet_ntoa(ipAddr->sin_addr);
        ARCH->unlockMutex(m_mutex);
        return s;
    }

    default:
        assert(0 && "unknown address family");
        return "";
    }
}

IArchNetwork::EAddressFamily
CArchNetworkBSD::getAddrFamily(CArchNetAddress addr)
{
    assert(addr != NULL);

    switch (addr->m_addr.sa_family) {
    case AF_INET:
        return kINET;

    default:
        return kUNKNOWN;
    }
}

void
CArchNetworkBSD::setAddrPort(CArchNetAddress addr, int port)
{
    assert(addr != NULL);

    switch (getAddrFamily(addr)) {
    case kINET: {
        struct sockaddr_in* ipAddr =
            reinterpret_cast<struct sockaddr_in*>(&addr->m_addr);
        ipAddr->sin_port = htons(port);
        break;
    }

    default:
        assert(0 && "unknown address family");
        break;
    }
}

int
CArchNetworkBSD::getAddrPort(CArchNetAddress addr)
{
    assert(addr != NULL);

    switch (getAddrFamily(addr)) {
    case kINET: {
        struct sockaddr_in* ipAddr =
            reinterpret_cast<struct sockaddr_in*>(&addr->m_addr);
        return ntohs(ipAddr->sin_port);
    }

    default:
        assert(0 && "unknown address family");
        return 0;
    }
}

bool
CArchNetworkBSD::isAnyAddr(CArchNetAddress addr)
{
    assert(addr != NULL);

    switch (getAddrFamily(addr)) {
    case kINET: {
        struct sockaddr_in* ipAddr =
            reinterpret_cast<struct sockaddr_in*>(&addr->m_addr);
        return (ipAddr->sin_addr.s_addr == INADDR_ANY &&
                addr->m_len == (socklen_t)sizeof(struct sockaddr_in));
    }

    default:
        assert(0 && "unknown address family");
        return true;
    }
}

bool
CArchNetworkBSD::isEqualAddr(CArchNetAddress a, CArchNetAddress b)
{
    return (a->m_len == b->m_len &&
            memcmp(&a->m_addr, &b->m_addr, a->m_len) == 0);
}

const int*
CArchNetworkBSD::getUnblockPipe()
{
    CArchMultithreadPosix* mt = CArchMultithreadPosix::getInstance();
    CArchThread thread        = mt->newCurrentThread();
    const int* p              = getUnblockPipeForThread(thread);
    ARCH->closeThread(thread);
    return p;
}

const int*
CArchNetworkBSD::getUnblockPipeForThread(CArchThread thread)
{
    CArchMultithreadPosix* mt = CArchMultithreadPosix::getInstance();
    int* unblockPipe          = (int*)mt->getNetworkDataForThread(thread);
    if (unblockPipe == NULL) {
        unblockPipe = new int[2];
        if (pipe(unblockPipe) != -1) {
            try {
                setBlockingOnSocket(unblockPipe[0], false);
                mt->setNetworkDataForCurrentThread(unblockPipe);
            }
            catch (...) {
                delete[] unblockPipe;
                unblockPipe = NULL;
            }
        }
        else {
            delete[] unblockPipe;
            unblockPipe = NULL;
        }
    }
    return unblockPipe;
}

void
CArchNetworkBSD::throwError(int err)
{
    switch (err) {
    case EINTR:
        ARCH->testCancelThread();
        throw XArchNetworkInterrupted(new XArchEvalUnix(err));

    case EACCES:
    case EPERM:
        throw XArchNetworkAccess(new XArchEvalUnix(err));

    case ENFILE:
    case EMFILE:
    case ENODEV:
    case ENOBUFS:
    case ENOMEM:
    case ENETDOWN:
#if defined(ENOSR)
    case ENOSR:
#endif
        throw XArchNetworkResource(new XArchEvalUnix(err));

    case EPROTOTYPE:
    case EPROTONOSUPPORT:
    case EAFNOSUPPORT:
    case EPFNOSUPPORT:
    case ESOCKTNOSUPPORT:
    case EINVAL:
    case ENOPROTOOPT:
    case EOPNOTSUPP:
    case ESHUTDOWN:
#if defined(ENOPKG)
    case ENOPKG:
#endif
        throw XArchNetworkSupport(new XArchEvalUnix(err));

    case EIO:
        throw XArchNetworkIO(new XArchEvalUnix(err));

    case EADDRNOTAVAIL:
        throw XArchNetworkNoAddress(new XArchEvalUnix(err));

    case EADDRINUSE:
        throw XArchNetworkAddressInUse(new XArchEvalUnix(err));

    case EHOSTUNREACH:
    case ENETUNREACH:
        throw XArchNetworkNoRoute(new XArchEvalUnix(err));

    case ENOTCONN:
        throw XArchNetworkNotConnected(new XArchEvalUnix(err));

    case EPIPE:
        throw XArchNetworkShutdown(new XArchEvalUnix(err));

    case ECONNABORTED:
    case ECONNRESET:
        throw XArchNetworkDisconnected(new XArchEvalUnix(err));

    case ECONNREFUSED:
        throw XArchNetworkConnectionRefused(new XArchEvalUnix(err));

    case EHOSTDOWN:
    case ETIMEDOUT:
        throw XArchNetworkTimedOut(new XArchEvalUnix(err));

    default:
        throw XArchNetwork(new XArchEvalUnix(err));
    }
}

void
CArchNetworkBSD::throwNameError(int err)
{
    static const char* s_msg[] = {
        "The specified host is unknown",
        "The requested name is valid but does not have an IP address",
        "A non-recoverable name server error occurred",
        "A temporary error occurred on an authoritative name server",
        "An unknown name server error occurred"
    };

    switch (err) {
    case HOST_NOT_FOUND:
        throw XArchNetworkNameUnknown(s_msg[0]);

    case NO_DATA:
        throw XArchNetworkNameNoAddress(s_msg[1]);

    case NO_RECOVERY:
        throw XArchNetworkNameFailure(s_msg[2]);

    case TRY_AGAIN:
        throw XArchNetworkNameUnavailable(s_msg[3]);

    default:
        throw XArchNetworkName(s_msg[4]);
    }
}