BEGIN LICENSE BLOCK *****
Version: EPL 2.0/GPL 2.0/LGPL 2.1
The contents of this file are subject to the Eclipse Public
License Version 2.0 (the "License"); you may not use this file
except in compliance with the License. You may obtain a copy of
the License at http://www.eclipse.org/legal/epl-v20.html
Software distributed under the License is distributed on an "AS
IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
implied. See the License for the specific language governing
rights and limitations under the License.
Copyright (C) 2007 Ola Bini 
Alternatively, the contents of this file may be used under the terms of
either of the GNU General Public License Version 2 or later (the "GPL"),
or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
in which case the provisions of the GPL or the LGPL are applicable instead
of those above. If you wish to allow use of your version of this file only
under the terms of either the GPL or the LGPL, and not to allow others to
use your version of this file under the terms of the EPL, indicate your
decision by deleting the provisions above and replace them with the notice
and other provisions required by the GPL or the LGPL. If you do not delete
the provisions above, a recipient may use your version of this file under
the terms of any one of the EPL, the GPL or the LGPL.
END LICENSE BLOCK /***** BEGIN LICENSE BLOCK *****
 * Version: EPL 2.0/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Eclipse Public
 * License Version 2.0 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy of
 * the License at http://www.eclipse.org/legal/epl-v20.html
 *
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * Copyright (C) 2007 Ola Bini <ola@ologix.com>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the EPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the EPL, the GPL or the LGPL.
 ***** END LICENSE BLOCK *****/

package org.jruby.ext.socket;

import java.io.IOException;
import java.net.ConnectException;
import java.net.DatagramSocket;
import java.net.InetSocketAddress;
import java.net.InterfaceAddress;
import java.net.NetworkInterface;
import java.net.Socket;
import java.net.SocketAddress;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.nio.channels.AlreadyConnectedException;
import java.nio.channels.Channel;
import java.nio.channels.ClosedChannelException;
import java.nio.channels.ConnectionPendingException;
import java.nio.channels.DatagramChannel;
import java.nio.channels.SelectableChannel;
import java.nio.channels.SocketChannel;
import java.util.Enumeration;
import java.util.regex.Pattern;

import jnr.constants.platform.AddressFamily;
import jnr.constants.platform.AddressInfo;
import jnr.constants.platform.Errno;
import jnr.constants.platform.INAddr;
import jnr.constants.platform.IP;
import jnr.constants.platform.IPProto;
import jnr.constants.platform.NameInfo;
import jnr.constants.platform.ProtocolFamily;
import jnr.constants.platform.Shutdown;
import jnr.constants.platform.Sock;
import jnr.constants.platform.SocketLevel;
import jnr.constants.platform.SocketOption;
import jnr.constants.platform.SocketMessage;
import jnr.constants.platform.TCP;
import jnr.netdb.Protocol;
import jnr.unixsocket.UnixSocketAddress;
import jnr.unixsocket.UnixSocketChannel;

import org.jruby.Ruby;
import org.jruby.RubyArray;
import org.jruby.RubyBoolean;
import org.jruby.RubyClass;
import org.jruby.RubyFixnum;
import org.jruby.RubyModule;
import org.jruby.anno.JRubyClass;
import org.jruby.anno.JRubyMethod;
import org.jruby.exceptions.RaiseException;
import org.jruby.runtime.Helpers;
import org.jruby.runtime.ObjectAllocator;
import org.jruby.runtime.ThreadContext;
import org.jruby.runtime.Visibility;
import org.jruby.runtime.builtin.IRubyObject;
import org.jruby.util.io.ChannelFD;
import org.jruby.util.io.Sockaddr;

import static org.jruby.runtime.Helpers.arrayOf;

Author:
Ola Bini/**
 * @author <a href="mailto:ola.bini@ki.se">Ola Bini</a>
 */
@JRubyClass(name="Socket", parent="BasicSocket", include="Socket::Constants")
public class RubySocket extends RubyBasicSocket {
    static void createSocket(Ruby runtime) {
        RubyClass rb_cSocket = runtime.defineClass("Socket", runtime.getClass("BasicSocket"), SOCKET_ALLOCATOR);

        RubyModule rb_mConstants = rb_cSocket.defineModuleUnder("Constants");
        // we don't have to define any that we don't support; see socket.c

        runtime.loadConstantSet(rb_mConstants, Sock.class);
        runtime.loadConstantSet(rb_mConstants, SocketOption.class);
        runtime.loadConstantSet(rb_mConstants, SocketLevel.class);
        runtime.loadConstantSet(rb_mConstants, ProtocolFamily.class);
        runtime.loadConstantSet(rb_mConstants, AddressFamily.class);
        runtime.loadConstantSet(rb_mConstants, INAddr.class);
        runtime.loadConstantSet(rb_mConstants, IPProto.class);
        runtime.loadConstantSet(rb_mConstants, Shutdown.class);
        runtime.loadConstantSet(rb_mConstants, TCP.class);
        runtime.loadConstantSet(rb_mConstants, NameInfo.class);
        runtime.loadConstantSet(rb_mConstants, SocketMessage.class);

        // this value seems to be hardcoded in MRI to 5 when not defined, but
        // it is 128 on OS X. We use 128 for now until we can get it added to
        // jnr-constants.
        rb_mConstants.setConstant("SOMAXCONN", RubyFixnum.newFixnum(runtime, 128));
        
        // for all platforms
        rb_mConstants.setConstant("IPPORT_RESERVED", RubyFixnum.newFixnum(runtime, 1024));
        rb_mConstants.setConstant("IPPORT_USERRESERVED", RubyFixnum.newFixnum(runtime, 5000));

        rb_mConstants.setConstant("AI_PASSIVE", runtime.newFixnum(1));
        rb_mConstants.setConstant("AI_CANONNAME", runtime.newFixnum(2));
        rb_mConstants.setConstant("AI_NUMERICHOST", runtime.newFixnum(4));
        rb_mConstants.setConstant("AI_ALL", runtime.newFixnum(256));
        rb_mConstants.setConstant("AI_V4MAPPED_CFG", runtime.newFixnum(512));
        rb_mConstants.setConstant("AI_ADDRCONFIG", runtime.newFixnum(1024));
        rb_mConstants.setConstant("AI_V4MAPPED", runtime.newFixnum(2048));
        rb_mConstants.setConstant("AI_NUMERICSERV", runtime.newFixnum(4096));

        rb_mConstants.setConstant("AI_DEFAULT", runtime.newFixnum(AddressInfo.AI_DEFAULT));
        rb_mConstants.setConstant("AI_MASK", runtime.newFixnum(AddressInfo.AI_MASK));

        // More constants needed by specs
        rb_mConstants.setConstant("IP_MULTICAST_TTL", runtime.newFixnum(IP.IP_MULTICAST_TTL.value()));
        rb_mConstants.setConstant("IP_MULTICAST_LOOP", runtime.newFixnum(IP.IP_MULTICAST_LOOP.value()));
        rb_mConstants.setConstant("IP_ADD_MEMBERSHIP", runtime.newFixnum(IP.IP_ADD_MEMBERSHIP.value()));
        rb_mConstants.setConstant("IP_MAX_MEMBERSHIPS", runtime.newFixnum(IP.IP_MAX_MEMBERSHIPS.value()));
        rb_mConstants.setConstant("IP_DEFAULT_MULTICAST_LOOP", runtime.newFixnum(IP.IP_DEFAULT_MULTICAST_LOOP));
        rb_mConstants.setConstant("IP_DEFAULT_MULTICAST_TTL", runtime.newFixnum(IP.IP_DEFAULT_MULTICAST_TTL));

        rb_cSocket.includeModule(rb_mConstants);

        rb_cSocket.defineAnnotatedMethods(RubySocket.class);
    }

    private static ObjectAllocator SOCKET_ALLOCATOR = new ObjectAllocator() {
        @Override
        public IRubyObject allocate(Ruby runtime, RubyClass klass) {
            return new RubySocket(runtime, klass);
        }
    };

    public RubySocket(Ruby runtime, RubyClass type) {
        super(runtime, type);
    }

    @JRubyMethod(meta = true)
    public static IRubyObject for_fd(ThreadContext context, IRubyObject socketClass, IRubyObject _fd) {
        Ruby runtime = context.runtime;

        if (_fd instanceof RubyFixnum) {
            int intFD = (int)((RubyFixnum)_fd).getLongValue();

            ChannelFD fd = runtime.getFilenoUtil().getWrapperFromFileno(intFD);

            if (fd == null) {
                throw runtime.newErrnoEBADFError();
            }

            RubySocket socket = (RubySocket)((RubyClass)socketClass).allocate();

            socket.initFieldsFromDescriptor(runtime, fd);

            socket.initSocket(fd);

            return socket;
        } else {
            throw runtime.newTypeError(_fd, context.runtime.getFixnum());
        }
    }

    @JRubyMethod(name = "initialize", visibility = Visibility.PRIVATE)
    public IRubyObject initialize(ThreadContext context, IRubyObject domain, IRubyObject type) {
        Ruby runtime = context.runtime;

        initFromArgs(runtime, domain, type);

        return this;
    }

    @JRubyMethod(name = "initialize", visibility = Visibility.PRIVATE)
    public IRubyObject initialize(ThreadContext context, IRubyObject domain, IRubyObject type, IRubyObject protocol) {
        Ruby runtime = context.runtime;

        initFromArgs(runtime, domain, type, protocol);

        return this;
    }

    @JRubyMethod()
    public IRubyObject connect_nonblock(ThreadContext context, IRubyObject arg) {
        return connect_nonblock(context, arg, context.nil);
    }

    @JRubyMethod()
    public IRubyObject connect_nonblock(ThreadContext context, IRubyObject arg, IRubyObject opts) {
        SocketAddress addr = addressForChannel(context, arg);

        return doConnectNonblock(context, addr, extractExceptionArg(context, opts));
    }

    @JRubyMethod()
    public IRubyObject connect(ThreadContext context, IRubyObject arg) {
        SocketAddress addr = addressForChannel(context, arg);

        return doConnect(context, addr, true);
    }

    @JRubyMethod()
    public IRubyObject bind(ThreadContext context, IRubyObject arg) {
        final SocketAddress sockaddr;

        if (arg instanceof Addrinfo) {
            Addrinfo addr = (Addrinfo) arg;
            sockaddr = addr.getSocketAddress();
        } else {
            sockaddr = Sockaddr.addressFromSockaddr(context, arg);
        }

        doBind(context, sockaddr);

        return RubyFixnum.zero(context.runtime);
    }

    @JRubyMethod
    public IRubyObject recvfrom(ThreadContext context, IRubyObject _length) {
        return RubyUDPSocket.recvfrom(this, context, _length);
    }

    
Overrides IPSocket#recvfrom
/**
     * Overrides IPSocket#recvfrom
     */
    @JRubyMethod
    public IRubyObject recvfrom(ThreadContext context, IRubyObject _length, IRubyObject _flags) {
        // TODO: handle flags
        return recvfrom(context, _length);
    }

    @JRubyMethod(required = 1, optional = 3)
    public IRubyObject recvfrom_nonblock(ThreadContext context, IRubyObject[] args) {
        if (getOpenFile() == null) {
            throw context.runtime.newErrnoENOTCONNError("socket is not connected");
        }
        return RubyUDPSocket.recvfrom_nonblock(this, context, args);
    }

    @JRubyMethod(notImplemented = true)
    public IRubyObject listen(ThreadContext context, IRubyObject backlog) {
        throw SocketUtils.sockerr(context.runtime, JRUBY_SERVER_SOCKET_ERROR);
    }

    @JRubyMethod(notImplemented = true)
    public IRubyObject accept(ThreadContext context) {
        throw SocketUtils.sockerr(context.runtime, JRUBY_SERVER_SOCKET_ERROR);
    }

    @JRubyMethod(notImplemented = true, optional = 1)
    public IRubyObject accept_nonblock(ThreadContext context, IRubyObject[] args) {
        throw SocketUtils.sockerr(context.runtime, JRUBY_SERVER_SOCKET_ERROR);
    }

    @JRubyMethod(meta = true)
    public static IRubyObject gethostname(ThreadContext context, IRubyObject recv) {
        return SocketUtils.gethostname(context);
    }

    @JRubyMethod(meta = true)
    public static IRubyObject getifaddrs(ThreadContext context, IRubyObject recv) {
        RubyArray list = RubyArray.newArray(context.runtime);
        RubyClass Ifaddr = (RubyClass) context.runtime.getClassFromPath("Socket::Ifaddr");
        try {
            Enumeration<NetworkInterface> en = NetworkInterface.getNetworkInterfaces();
            while (en.hasMoreElements()) {
                NetworkInterface iface = en.nextElement();
                // create interface link layer ifaddr
                list.append(new Ifaddr(context.runtime, Ifaddr, iface));
                for ( InterfaceAddress iaddr : iface.getInterfaceAddresses() ) {
                    list.append(new Ifaddr(context.runtime, Ifaddr, iface, iaddr));
                }
            }
        }
        catch (SocketException|RuntimeException ex) {
            if ( ex instanceof RaiseException ) throw (RaiseException) ex;
            throw SocketUtils.sockerr_with_trace(context.runtime, "getifaddrs: " + ex.toString(), ex.getStackTrace());
        }
        return list;
    }

    @JRubyMethod(required = 1, rest = true, meta = true)
    public static IRubyObject gethostbyaddr(ThreadContext context, IRubyObject recv, IRubyObject[] args) {
        return SocketUtils.gethostbyaddr(context, args);
    }

    @JRubyMethod(required = 1, optional = 1, meta = true)
    public static IRubyObject getservbyname(ThreadContext context, IRubyObject recv, IRubyObject[] args) {
        return SocketUtils.getservbyname(context, args);
    }

    @JRubyMethod(name = {"pack_sockaddr_in", "sockaddr_in"}, meta = true)
    public static IRubyObject pack_sockaddr_in(ThreadContext context, IRubyObject recv, IRubyObject port, IRubyObject host) {
        return Sockaddr.pack_sockaddr_in(context, port, host);
    }

    @JRubyMethod(meta = true)
    public static IRubyObject unpack_sockaddr_in(ThreadContext context, IRubyObject recv, IRubyObject addr) {
        return Sockaddr.unpack_sockaddr_in(context, addr);
    }

    @JRubyMethod(name = {"pack_sockaddr_un", "sockaddr_un"}, meta = true)
    public static IRubyObject pack_sockaddr_un(ThreadContext context, IRubyObject recv, IRubyObject filename) {
        String path = filename.convertToString().asJavaString();
        return Sockaddr.pack_sockaddr_un(context, path);
    }

    @JRubyMethod(meta = true)
    public static IRubyObject unpack_sockaddr_un(ThreadContext context, IRubyObject recv, IRubyObject addr) {
        return Sockaddr.unpack_sockaddr_un(context, addr);
    }

    @JRubyMethod(meta = true)
    public static IRubyObject gethostbyname(ThreadContext context, IRubyObject recv, IRubyObject hostname) {
        return SocketUtils.gethostbyname(context, hostname);
    }

    @JRubyMethod(required = 2, optional = 5, meta = true)
    public static IRubyObject getaddrinfo(ThreadContext context, IRubyObject recv, IRubyObject[] args) {
        return SocketUtils.getaddrinfo(context, args);
    }

    @JRubyMethod(required = 1, optional = 1, meta = true)
    public static IRubyObject getnameinfo(ThreadContext context, IRubyObject recv, IRubyObject[] args) {
        return SocketUtils.getnameinfo(context, args);
    }

    @JRubyMethod(meta = true)
    public static IRubyObject ip_address_list(ThreadContext context, IRubyObject self) {
        return SocketUtils.ip_address_list(context);
    }

    @JRubyMethod(name = {"socketpair", "pair"}, meta = true)
    public static IRubyObject socketpair(ThreadContext context, IRubyObject recv, IRubyObject domain, IRubyObject type, IRubyObject protocol) {
        ProtocolFamily pf = SocketUtils.protocolFamilyFromArg(protocol);
        if (pf == null ) pf = ProtocolFamily.PF_UNIX;

        if (pf != ProtocolFamily.PF_UNIX && pf.ordinal() != 0) {
            throw context.runtime.newErrnoEOPNOTSUPPError("Socket.socketpair only supports streaming UNIX sockets");
        }

        return socketpair(context, recv, domain, type);
    }

    @JRubyMethod(name = {"socketpair", "pair"}, meta = true)
    public static IRubyObject socketpair(ThreadContext context, IRubyObject recv, IRubyObject domain, IRubyObject type) {
        AddressFamily af = SocketUtils.addressFamilyFromArg(domain);
        if (af == null) af = AddressFamily.AF_UNIX;
        Sock s = SocketUtils.sockFromArg(type);
        if (s == null) s = Sock.SOCK_STREAM;

        if (af != AddressFamily.AF_UNIX || s != Sock.SOCK_STREAM) {
            throw context.runtime.newErrnoEOPNOTSUPPError("Socket.socketpair only supports streaming UNIX sockets");
        }

        final Ruby runtime = context.runtime;

        // TODO: type and protocol

        UnixSocketChannel[] sp;

        try {
            sp = UnixSocketChannel.pair();
            final RubyClass socketClass = runtime.getClass("Socket");

            RubySocket sock0 = new RubySocket(runtime, socketClass);
            ChannelFD fd0 = newChannelFD(runtime, sp[0]);
            sock0.initFieldsFromDescriptor(runtime, fd0);
            sock0.initSocket(fd0);

            RubySocket sock1 = new RubySocket(runtime, socketClass);
            ChannelFD fd1 = newChannelFD(runtime, sp[1]);
            sock1.initFieldsFromDescriptor(runtime, fd1);
            sock1.initSocket(fd1);

            return runtime.newArray(sock0, sock1);

        } catch (IOException ioe) {
            throw runtime.newIOErrorFromException(ioe);
        }
    }

    private void initFieldsFromDescriptor(Ruby runtime, ChannelFD fd) {
        Channel mainChannel = fd.ch;

        if (mainChannel instanceof SocketChannel) {
            // ok, it's a socket...set values accordingly
            // just using AF_INET since we can't tell from SocketChannel...
            soDomain = AddressFamily.AF_INET;
            soType = Sock.SOCK_STREAM;
            soProtocolFamily = ProtocolFamily.PF_INET;
            soProtocol = Protocol.getProtocolByName("tcp");

        } else if (mainChannel instanceof UnixSocketChannel) {
            soDomain = AddressFamily.AF_UNIX;
            soType = Sock.SOCK_STREAM;
            soProtocolFamily = ProtocolFamily.PF_UNIX;

        } else if (mainChannel instanceof DatagramChannel) {
            // datagram, set accordingly
            // again, AF_INET
            soDomain = AddressFamily.AF_INET;
            soType = Sock.SOCK_DGRAM;
            soProtocolFamily = ProtocolFamily.PF_INET;

        } else {
            throw runtime.newErrnoENOTSOCKError("can't Socket.new/for_fd against a non-socket");
        }
    }

    private void initFromArgs(Ruby runtime, IRubyObject domain, IRubyObject type, IRubyObject protocol) {
        setProtocol(protocol);
        initFromArgs(runtime, domain, type);
    }

    private void initFromArgs(Ruby runtime, IRubyObject domain, IRubyObject type) {
        setDomain(runtime, domain);
        setType(runtime, type);

        ChannelFD fd = initChannelFD(runtime);
        initSocket(fd);
    }

    protected void initFromServer(Ruby runtime, RubySocket serverSocket, SocketChannel socketChannel) {
        soDomain = serverSocket.soDomain;
        soType = serverSocket.soType;
        soProtocol = serverSocket.soProtocol;

        initSocket(newChannelFD(runtime, socketChannel));
    }

    protected ChannelFD initChannelFD(Ruby runtime) {
        try {
            Channel channel;
            switch (soType) {
                case SOCK_STREAM:
                    if ( soProtocolFamily == ProtocolFamily.PF_UNIX ||
                         soProtocolFamily == ProtocolFamily.PF_LOCAL ) {
                        channel = UnixSocketChannel.open();
                    }
                    else if ( soProtocolFamily == ProtocolFamily.PF_INET ||
                              soProtocolFamily == ProtocolFamily.PF_INET6 ||
                              soProtocolFamily == ProtocolFamily.PF_UNSPEC ) {
                        channel = SocketChannel.open();
                    }
                    else {
                        throw runtime.newArgumentError("unsupported protocol family `" + soProtocolFamily + "'");
                    }
                    break;
                case SOCK_DGRAM:
                    channel = DatagramChannel.open();
                    break;
                default:
                    throw runtime.newArgumentError("unsupported socket type `" + soType + "'");
            }

            return newChannelFD(runtime, channel);
        }
        catch (IOException e) {
            throw sockerr(runtime, "initialize: " + e.toString(), e);
        }
    }

    private void setProtocol(IRubyObject protocol) {
        soProtocol = SocketUtils.protocolFromArg(protocol);
    }

    private void setType(Ruby runtime, IRubyObject type) {
        Sock sockType = SocketUtils.sockFromArg(type);

        if (sockType == null) {
            throw SocketUtils.sockerr(runtime, "unknown socket type " + type);
        }

        soType = sockType;
    }

    private void setDomain(Ruby runtime, IRubyObject domain) {
        AddressFamily family = SocketUtils.addressFamilyFromArg(domain);

        if (family == null) {
            throw SocketUtils.sockerr(runtime, "unknown socket domain " + domain);
        }

        soDomain = family;
        String name = soDomain.name();
        if (name.startsWith("pseudo_")) name = name.substring(7);
        soProtocolFamily = ProtocolFamily.valueOf("PF" + name.substring(2));
    }

    private IRubyObject doConnectNonblock(ThreadContext context, SocketAddress addr, boolean ex) {
        Channel channel = getChannel();

        if ( ! (channel instanceof SelectableChannel) ) {
            throw context.runtime.newErrnoENOPROTOOPTError();
        }

        SelectableChannel selectable = (SelectableChannel) channel;
        synchronized (selectable.blockingLock()) {
            boolean oldBlocking = selectable.isBlocking();
            try {
                selectable.configureBlocking(false);

                try {
                    return doConnect(context, addr, ex);

                } finally {
                    selectable.configureBlocking(oldBlocking);
                }

            }
            catch (ClosedChannelException e) {
                throw context.runtime.newErrnoECONNREFUSEDError();
            }
            catch (IOException e) {
                throw sockerr(context.runtime, "connect(2): name or service not known", e);
            }
        }
    }

    protected IRubyObject doConnect(ThreadContext context, SocketAddress addr, boolean ex) {
        Ruby runtime = context.runtime;
        Channel channel = getChannel();

        try {
            boolean result = true;
            if (channel instanceof SocketChannel) {
                SocketChannel socket = (SocketChannel) channel;

                if (socket.isConnectionPending()) {
                    // connection initiated but not finished
                    result = socket.finishConnect();
                } else {
                    result = socket.connect(addr);
                }
            }
            else if (channel instanceof UnixSocketChannel) {
                result = ((UnixSocketChannel) channel).connect((UnixSocketAddress) addr);

            }
            else if (channel instanceof DatagramChannel) {
                ((DatagramChannel)channel).connect(addr);
            }
            else {
                throw runtime.newErrnoENOPROTOOPTError();
            }

            if ( ! result ) {
                if (!ex) return runtime.newSymbol("wait_writable");
                throw runtime.newErrnoEINPROGRESSWritableError();
            }
        }
        catch (AlreadyConnectedException e) {
            if (!ex) return runtime.newFixnum(0);
            throw runtime.newErrnoEISCONNError();
        }
        catch (ConnectionPendingException e) {
            throw runtime.newErrnoEINPROGRESSWritableError();
        }
        catch (UnknownHostException e) {
            throw SocketUtils.sockerr(runtime, "connect(2): unknown host");
        }
        catch (SocketException e) {
            // Subclasses of SocketException all indicate failure to connect, which leaves the channel closed.
            // At this point the socket channel is no longer usable, so we clean up.
            getOpenFile().cleanup(runtime, true);
            throw buildSocketException(runtime, e, "connect(2)", addr);
        }
        catch (IOException e) {
            throw sockerr(runtime, "connect(2): name or service not known", e);
        }
        catch (IllegalArgumentException e) {
            throw sockerr(runtime, e.getMessage(), e);
        }

        return runtime.newFixnum(0);
    }

    protected void doBind(ThreadContext context, SocketAddress iaddr) {
        Ruby runtime = context.runtime;

        Channel channel = getChannel();

        try {
            if (channel instanceof SocketChannel) {
                Socket socket = ((SocketChannel) channel).socket();
                socket.bind(iaddr);
            }
            else if (channel instanceof UnixSocketChannel) {
                // do nothing
            }
            else if (channel instanceof DatagramChannel) {
                DatagramSocket socket = ((DatagramChannel) channel).socket();
                socket.bind(iaddr);
            }
            else {
                throw runtime.newErrnoENOPROTOOPTError();
            }
        }
        catch (UnknownHostException e) {
            throw SocketUtils.sockerr(runtime, "bind(2): unknown host");
        }
        catch (SocketException e) {
            throw buildSocketException(runtime, e, "bind(2)", iaddr); // throws
        }
        catch (IOException e) {
            throw sockerr(runtime, "bind(2): name or service not known", e);
        }
        catch (IllegalArgumentException e) {
            throw sockerr(runtime, e.getMessage(), e);
        }
    }

    static RaiseException buildSocketException(final Ruby runtime, final SocketException ex,
        final String caller, final SocketAddress addr) {

        final Errno errno = Helpers.errnoFromException(ex);
        final String callerWithAddr = caller + " for " + formatAddress(addr);

        if (errno != null) {
            return runtime.newErrnoFromErrno(errno, callerWithAddr);
        }

        final String message = ex.getMessage();

        if (message != null) {
            // This is ugly, but what can we do, Java provides the same exception type
            // for different situations, so we differentiate the errors
            // based on the exception's message.
            if (ALREADY_BOUND_PATTERN.matcher(message).find()) {
                return runtime.newErrnoEINVALError(callerWithAddr);
            }
            if (ADDR_NOT_AVAIL_PATTERN.matcher(message).find()) {
                return runtime.newErrnoEADDRNOTAVAILError(callerWithAddr);
            }
        }

        return runtime.newIOError(callerWithAddr);
    }

    private static CharSequence formatAddress(final SocketAddress addr) {
        if ( addr == null ) return null;
        final String str = addr.toString();
        if ( str.length() > 0 && str.charAt(0) == '/' ) {
            return str.substring(1);
        }
        return str;
    }

    private SocketAddress addressForChannel(ThreadContext context, IRubyObject arg) {
        if (arg instanceof Addrinfo) return ((Addrinfo) arg).getSocketAddress();

        switch (soProtocolFamily) {
            case PF_UNIX:
            case PF_LOCAL:
                return Sockaddr.addressFromSockaddr_un(context, arg);

            case PF_INET:
            case PF_INET6:
            case PF_UNSPEC:
                return Sockaddr.addressFromSockaddr_in(context, arg);

            default:
                throw context.runtime.newArgumentError("unsupported protocol family `" + soProtocolFamily + "'");
        }
    }

    @Override
    protected IRubyObject addrFor(ThreadContext context, InetSocketAddress addr, boolean reverse) {
        final Ruby runtime = context.runtime;

        return new Addrinfo(runtime, runtime.getClass("Addrinfo"), addr.getAddress(), addr.getPort(), Sock.SOCK_DGRAM);
    }

    @Override
    @JRubyMethod
    public IRubyObject close(final ThreadContext context) {
        if (getOpenFile() != null) {
            if (isClosed()) return context.nil;
            openFile.checkClosed();
            return rbIoClose(context);
        }
        return context.nil;
    }

    @Override
    public RubyBoolean closed_p(ThreadContext context) {
        if (getOpenFile() == null) return context.fals;

        return super.closed_p(context);
    }

    protected SocketAddress getSocketAddress() {
        Channel channel = getChannel();

        return SocketType.forChannel(channel).getLocalSocketAddress(channel);
    }

    @Deprecated
    public static RuntimeException sockerr(Ruby runtime, String msg) {
        return SocketUtils.sockerr(runtime, msg);
    }

    private static final Pattern ALREADY_BOUND_PATTERN = Pattern.compile("[Aa]lready.*bound");
    private static final Pattern ADDR_NOT_AVAIL_PATTERN = Pattern.compile("assign.*address");
    //private static final Pattern PERM_DENIED_PATTERN = Pattern.compile("[Pp]ermission.*denied");

    protected AddressFamily soDomain;
    protected ProtocolFamily soProtocolFamily;
    protected Sock soType;
    protected Protocol soProtocol = Protocol.getProtocolByNumber(0);

    private static final String JRUBY_SERVER_SOCKET_ERROR =
            "use ServerSocket for servers (http://wiki.jruby.org/ServerSocket)";
}// RubySocket