* ext/socket: split files for each class.

* ext/socket/rubysocket.h: common header.

* ext/socket/basicsocket.c: new file for BasicSocket.

* ext/socket/ipsocket.c: new file for IPSocket.

* ext/socket/tcpsocket.c: new file for TCPSocket.

* ext/socket/tcpserver.c: new file for TCPServer.

* ext/socket/sockssocket.c: new file for SOCKSSocket.

* ext/socket/udpsocket.c: new file for UDPSocket.

* ext/socket/unixsocket.c: new file for UNIXSocket.

* ext/socket/unixserver.c: new file for UNIXServer.

* ext/socket/socket.c: now for Socket.

* ext/socket/raddrinfo.c: new file for AddrInfo and name resolution.

* ext/socket/constants.c: new file for constants.

* ext/socket/init.c: new file for utilities.

* ext/socket/mkconstants.rb: export *_to_int.

* ext/socket/extconf.rb: add new object files.

* ext/socket/depend: add dependencies for new files.

* ext/.document: add new files.



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@21619 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

18 files changed, 4579 insertions, 4207 deletions

diff --git a/ChangeLog b/ChangeLog
index bd1c516646..cb34515467 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,41 @@
+Sat Jan 17 12:46:17 2009  Tanaka Akira  <akr@fsij.org>
+
+	* ext/socket: split files for each class.
+
+	* ext/socket/rubysocket.h: common header.
+
+	* ext/socket/basicsocket.c: new file for BasicSocket.
+
+	* ext/socket/ipsocket.c: new file for IPSocket.
+
+	* ext/socket/tcpsocket.c: new file for TCPSocket.
+
+	* ext/socket/tcpserver.c: new file for TCPServer.
+
+	* ext/socket/sockssocket.c: new file for SOCKSSocket.
+
+	* ext/socket/udpsocket.c: new file for UDPSocket.
+
+	* ext/socket/unixsocket.c: new file for UNIXSocket.
+
+	* ext/socket/unixserver.c: new file for UNIXServer.
+
+	* ext/socket/socket.c: now for Socket.
+
+	* ext/socket/raddrinfo.c: new file for AddrInfo and name resolution.
+
+	* ext/socket/constants.c: new file for constants.
+
+	* ext/socket/init.c: new file for utilities.
+
+	* ext/socket/mkconstants.rb: export *_to_int.
+
+	* ext/socket/extconf.rb: add new object files.
+
+	* ext/socket/depend: add dependencies for new files.
+
+	* ext/.document: add new files.
+
 Sat Jan 17 11:12:37 2009  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* cont.c (cont_restore_0): padding size doesn't need to be large
diff --git a/ext/.document b/ext/.document
index ecfad12c37..4e92aa7d29 100644
--- a/ext/.document
+++ b/ext/.document
@@ -9,7 +9,18 @@ io/wait/wait.c
 nkf/lib/kconv.rb
 nkf/nkf.c
 readline/readline.c
+socket/init.c
+socket/raddrinfo.c
+socket/basicsocket.c
+socket/ipsocket.c
+socket/tcpsocket.c
+socket/tcpserver.c
+socket/sockssocket.c
+socket/udpsocket.c
+socket/unixsocket.c
+socket/unixserver.c
 socket/socket.c
+socket/constants.c
 stringio/stringio.c
 strscan/strscan.c
 win32ole
diff --git a/ext/socket/basicsocket.c b/ext/socket/basicsocket.c
new file mode 100644
index 0000000000..4b8e94653f
--- /dev/null
+++ b/ext/socket/basicsocket.c
@@ -0,0 +1,640 @@
+/************************************************
+
+  basicsocket.c -
+
+  created at: Thu Mar 31 12:21:29 JST 1994
+
+  Copyright (C) 1993-2007 Yukihiro Matsumoto
+
+************************************************/
+
+#include "rubysocket.h"
+
+/*
+ * call-seq:
+ *   BasicSocket.for_fd(fd) => basicsocket
+ *
+ * Returns a socket object which contains the file descriptor, _fd_.
+ *
+ *   # If invoked by inetd, STDIN/STDOUT/STDERR is a socket.
+ *   STDIN_SOCK = Socket.for_fd(STDIN.fileno)
+ *   p STDIN_SOCK.remote_address
+ *
+ */
+static VALUE
+bsock_s_for_fd(VALUE klass, VALUE fd)
+{
+    rb_io_t *fptr;
+    VALUE sock = init_sock(rb_obj_alloc(klass), NUM2INT(fd));
+
+    GetOpenFile(sock, fptr);
+
+    return sock;
+}
+
+/*
+ * call-seq:
+ *   basicsocket.shutdown([how]) => 0
+ *
+ * Calls shutdown(2) system call.
+ *
+ * s.shutdown(Socket::SHUT_RD) disallows further read.
+ *
+ * s.shutdown(Socket::SHUT_WR) disallows further write.
+ *
+ * s.shutdown(Socket::SHUT_RDWR) disallows further read and write.
+ *
+ * _how_ can be symbol or string:
+ * - :RD, :SHUT_RD, "RD" and "SHUT_RD" are accepted as Socket::SHUT_RD.
+ * - :WR, :SHUT_WR, "WR" and "SHUT_WR" are accepted as Socket::SHUT_WR.
+ * - :RDWR, :SHUT_RDWR, "RDWR" and "SHUT_RDWR" are accepted as Socket::SHUT_RDWR.
+ *
+ *   UNIXSocket.pair {|s1, s2|
+ *     s1.puts "ping"
+ *     s1.shutdown(:WR)
+ *     p s2.read          #=> "ping\n"
+ *     s2.puts "pong"
+ *     s2.close
+ *     p s1.read          #=> "pong\n"
+ *   }
+ *   
+ */
+static VALUE
+bsock_shutdown(int argc, VALUE *argv, VALUE sock)
+{
+    VALUE howto;
+    int how;
+    rb_io_t *fptr;
+
+    if (rb_safe_level() >= 4 && !OBJ_TAINTED(sock)) {
+	rb_raise(rb_eSecurityError, "Insecure: can't shutdown socket");
+    }
+    rb_scan_args(argc, argv, "01", &howto);
+    if (howto == Qnil)
+	how = SHUT_RDWR;
+    else {
+	how = shutdown_how_arg(howto);
+        if (how != SHUT_WR && how != SHUT_RD && how != SHUT_RDWR) {
+	    rb_raise(rb_eArgError, "`how' should be either :SHUT_RD, :SHUT_WR, :SHUT_RDWR");
+	}
+    }
+    GetOpenFile(sock, fptr);
+    if (shutdown(fptr->fd, how) == -1)
+	rb_sys_fail(0);
+
+    return INT2FIX(0);
+}
+
+/*
+ * call-seq:
+ *   basicsocket.close_read => nil
+ *
+ * Disallows further read.
+ *
+ *   s1, s2 = UNIXSocket.pair
+ *   s1.close_read
+ *   s2.puts #=> Broken pipe (Errno::EPIPE)
+ */
+static VALUE
+bsock_close_read(VALUE sock)
+{
+    rb_io_t *fptr;
+
+    if (rb_safe_level() >= 4 && !OBJ_TAINTED(sock)) {
+	rb_raise(rb_eSecurityError, "Insecure: can't close socket");
+    }
+    GetOpenFile(sock, fptr);
+    shutdown(fptr->fd, 0);
+    if (!(fptr->mode & FMODE_WRITABLE)) {
+	return rb_io_close(sock);
+    }
+    fptr->mode &= ~FMODE_READABLE;
+
+    return Qnil;
+}
+
+/*
+ * call-seq:
+ *   basicsocket.close_write => nil
+ *
+ * Disallows further write.
+ *
+ *   UNIXSocket.pair {|s1, s2|
+ *     s1.print "ping"
+ *     s1.close_write
+ *     p s2.read        #=> "ping"
+ *     s2.print "pong"
+ *     s2.close
+ *     p s1.read        #=> "pong"
+ *   }
+ */
+static VALUE
+bsock_close_write(VALUE sock)
+{
+    rb_io_t *fptr;
+
+    if (rb_safe_level() >= 4 && !OBJ_TAINTED(sock)) {
+	rb_raise(rb_eSecurityError, "Insecure: can't close socket");
+    }
+    GetOpenFile(sock, fptr);
+    if (!(fptr->mode & FMODE_READABLE)) {
+	return rb_io_close(sock);
+    }
+    shutdown(fptr->fd, 1);
+    fptr->mode &= ~FMODE_WRITABLE;
+
+    return Qnil;
+}
+
+/*
+ * Document-method: setsockopt
+ * call-seq: setsockopt(level, optname, optval)
+ *
+ * Sets a socket option. These are protocol and system specific, see your
+ * local sytem documentation for details.
+ *
+ * === Parameters
+ * * +level+ is an integer, usually one of the SOL_ constants such as
+ *   Socket::SOL_SOCKET, or a protocol level.
+ * * +optname+ is an integer, usually one of the SO_ constants, such
+ *   as Socket::SO_REUSEADDR.
+ * * +optval+ is the value of the option, it is passed to the underlying
+ *   setsockopt() as a pointer to a certain number of bytes. How this is
+ *   done depends on the type:
+ *   - Fixnum: value is assigned to an int, and a pointer to the int is
+ *     passed, with length of sizeof(int).
+ *   - true or false: 1 or 0 (respectively) is assigned to an int, and the
+ *     int is passed as for a Fixnum. Note that +false+ must be passed,
+ *     not +nil+.
+ *   - String: the string's data and length is passed to the socket.
+ *
+ * === Examples
+ *
+ * Some socket options are integers with boolean values, in this case
+ * #setsockopt could be called like this:
+ *   sock.setsockopt(Socket::SOL_SOCKET,Socket::SO_REUSEADDR, true)
+ *
+ * Some socket options are integers with numeric values, in this case
+ * #setsockopt could be called like this:
+ *   sock.setsockopt(Socket::IPPROTO_IP, Socket::IP_TTL, 255)
+ *
+ * Option values may be structs. Passing them can be complex as it involves
+ * examining your system headers to determine the correct definition. An
+ * example is an +ip_mreq+, which may be defined in your system headers as:
+ *   struct ip_mreq {
+ *     struct  in_addr imr_multiaddr;
+ *     struct  in_addr imr_interface;
+ *   };
+ * 
+ * In this case #setsockopt could be called like this:
+ *   optval =  IPAddr.new("224.0.0.251") + Socket::INADDR_ANY
+ *   sock.setsockopt(Socket::IPPROTO_IP, Socket::IP_ADD_MEMBERSHIP, optval)
+ *
+*/
+static VALUE
+bsock_setsockopt(VALUE sock, VALUE lev, VALUE optname, VALUE val)
+{
+    int level, option;
+    rb_io_t *fptr;
+    int i;
+    char *v;
+    int vlen;
+
+    rb_secure(2);
+    level = level_arg(lev);
+    option = optname_arg(level, optname);
+
+    switch (TYPE(val)) {
+      case T_FIXNUM:
+	i = FIX2INT(val);
+	goto numval;
+      case T_FALSE:
+	i = 0;
+	goto numval;
+      case T_TRUE:
+	i = 1;
+      numval:
+	v = (char*)&i; vlen = sizeof(i);
+	break;
+      default:
+	StringValue(val);
+	v = RSTRING_PTR(val);
+	vlen = RSTRING_LEN(val);
+	break;
+    }
+
+#define rb_sys_fail_path(path) rb_sys_fail(NIL_P(path) ? 0 : RSTRING_PTR(path))
+
+    GetOpenFile(sock, fptr);
+    if (setsockopt(fptr->fd, level, option, v, vlen) < 0)
+	rb_sys_fail_path(fptr->pathv);
+
+    return INT2FIX(0);
+}
+
+/*
+ * Document-method: getsockopt
+ * call-seq: getsockopt(level, optname)
+ *
+ * Gets a socket option. These are protocol and system specific, see your
+ * local sytem documentation for details. The option is returned as
+ * a String with the data being the binary value of the socket option.
+ *
+ * === Parameters
+ * * +level+ is an integer, usually one of the SOL_ constants such as
+ *   Socket::SOL_SOCKET, or a protocol level.
+ * * +optname+ is an integer, usually one of the SO_ constants, such
+ *   as Socket::SO_REUSEADDR.
+ *
+ * === Examples
+ *
+ * Some socket options are integers with boolean values, in this case
+ * #getsockopt could be called like this:
+ *   optval = sock.getsockopt(Socket::SOL_SOCKET,Socket::SO_REUSEADDR)
+ *   optval = optval.unpack "i"
+ *   reuseaddr = optval[0] == 0 ? false : true
+ *
+ * Some socket options are integers with numeric values, in this case
+ * #getsockopt could be called like this:
+ *   optval = sock.getsockopt(Socket::IPPROTO_IP, Socket::IP_TTL)
+ *   ipttl = optval.unpack("i")[0]
+ *
+ * Option values may be structs. Decoding them can be complex as it involves
+ * examining your system headers to determine the correct definition. An
+ * example is a +struct linger+, which may be defined in your system headers
+ * as:
+ *   struct linger {
+ *     int l_onoff;
+ *     int l_linger;
+ *   };
+ * 
+ * In this case #getsockopt could be called like this:
+ *   optval =  sock.getsockopt(Socket::SOL_SOCKET, Socket::SO_LINGER)
+ *   onoff, linger = optval.unpack "ii"
+*/
+static VALUE
+bsock_getsockopt(VALUE sock, VALUE lev, VALUE optname)
+{
+#if !defined(__BEOS__)
+    int level, option;
+    socklen_t len;
+    char *buf;
+    rb_io_t *fptr;
+
+    level = level_arg(lev);
+    option = optname_arg(level, optname);
+    len = 256;
+    buf = ALLOCA_N(char,len);
+
+    GetOpenFile(sock, fptr);
+    if (getsockopt(fptr->fd, level, option, buf, &len) < 0)
+	rb_sys_fail_path(fptr->pathv);
+
+    return rb_str_new(buf, len);
+#else
+    rb_notimplement();
+#endif
+}
+
+/*
+ * call-seq:
+ *   basicsocket.getsockname => sockaddr
+ *
+ * Returns the local address of the socket as a sockaddr string.
+ *
+ *   TCPServer.open("127.0.0.1", 15120) {|serv|
+ *     p serv.getsockname #=> "\x02\x00;\x10\x7F\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00"
+ *   }
+ */
+static VALUE
+bsock_getsockname(VALUE sock)
+{
+    char buf[1024];
+    socklen_t len = sizeof buf;
+    rb_io_t *fptr;
+
+    GetOpenFile(sock, fptr);
+    if (getsockname(fptr->fd, (struct sockaddr*)buf, &len) < 0)
+	rb_sys_fail("getsockname(2)");
+    return rb_str_new(buf, len);
+}
+
+/*
+ * call-seq:
+ *   basicsocket.getpeername => sockaddr
+ *
+ * Returns the remote address of the socket as a sockaddr string.
+ *
+ *   TCPServer.open("127.0.0.1", 1440) {|serv|
+ *     c = TCPSocket.new("127.0.0.1", 1440)
+ *     s = serv.accept
+ *     p s.getpeername #=> "\x02\x00\x82u\x7F\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00"
+ *   }
+ *
+ */
+static VALUE
+bsock_getpeername(VALUE sock)
+{
+    char buf[1024];
+    socklen_t len = sizeof buf;
+    rb_io_t *fptr;
+
+    GetOpenFile(sock, fptr);
+    if (getpeername(fptr->fd, (struct sockaddr*)buf, &len) < 0)
+	rb_sys_fail("getpeername(2)");
+    return rb_str_new(buf, len);
+}
+
+/*
+ * call-seq:
+ *   bsock.local_address => addrinfo
+ *
+ * Returns an AddrInfo object for local address obtained by getsockname.
+ *
+ * Note that addrinfo.protocol is filled by 0.
+ *
+ *   TCPServer.open("127.0.0.1", 1512) {|serv|
+ *     p serv.local_address #=> #<AddrInfo: 127.0.0.1:1512 TCP>
+ *   }
+ *
+ */
+static VALUE
+bsock_local_address(VALUE sock)
+{
+    char buf[1024];
+    socklen_t len = sizeof buf;
+    rb_io_t *fptr;
+
+    GetOpenFile(sock, fptr);
+    if (getsockname(fptr->fd, (struct sockaddr*)buf, &len) < 0)
+	rb_sys_fail("getsockname(2)");
+    return fd_socket_addrinfo(fptr->fd, (struct sockaddr *)buf, len);
+}
+
+/*
+ * call-seq:
+ *   bsock.remote_address => addrinfo
+ *
+ * Returns an AddrInfo object for remote address obtained by getpeername.
+ *
+ * Note that addrinfo.protocol is filled by 0.
+ *
+ *   TCPServer.open("127.0.0.1", 1728) {|serv|
+ *     c = TCPSocket.new("127.0.0.1", 1728)
+ *     s = serv.accept
+ *     p s.remote_address #=> #<AddrInfo: 127.0.0.1:36504 TCP>
+ *   }
+ *
+ */
+static VALUE
+bsock_remote_address(VALUE sock)
+{
+    char buf[1024];
+    socklen_t len = sizeof buf;
+    rb_io_t *fptr;
+
+    GetOpenFile(sock, fptr);
+    if (getpeername(fptr->fd, (struct sockaddr*)buf, &len) < 0)
+	rb_sys_fail("getpeername(2)");
+    return fd_socket_addrinfo(fptr->fd, (struct sockaddr *)buf, len);
+}
+
+/*
+ * call-seq:
+ *   basicsocket.send(mesg, flags [, sockaddr_to]) => numbytes_sent
+ *
+ * send _mesg_ via _basicsocket_.
+ *
+ * _mesg_ should be a string.
+ *
+ * _flags_ should be a bitwise OR of Socket::MSG_* constants.
+ *
+ * _sockaddr_to_ should be a packed sockaddr string or an addrinfo.
+ *
+ *   TCPSocket.open("localhost", 80) {|s|
+ *     s.send "GET / HTTP/1.0\r\n\r\n", 0
+ *     p s.read
+ *   }
+ */
+VALUE
+bsock_send(int argc, VALUE *argv, VALUE sock)
+{
+    struct send_arg arg;
+    VALUE flags, to;
+    rb_io_t *fptr;
+    int n;
+    rb_blocking_function_t *func;
+
+    rb_secure(4);
+    rb_scan_args(argc, argv, "21", &arg.mesg, &flags, &to);
+
+    StringValue(arg.mesg);
+    if (!NIL_P(to)) {
+	SockAddrStringValue(to);
+	to = rb_str_new4(to);
+	arg.to = (struct sockaddr *)RSTRING_PTR(to);
+	arg.tolen = RSTRING_LEN(to);
+	func = sendto_blocking;
+    }
+    else {
+	func = send_blocking;
+    }
+    GetOpenFile(sock, fptr);
+    arg.fd = fptr->fd;
+    arg.flags = NUM2INT(flags);
+    while (rb_thread_fd_writable(arg.fd),
+	   (n = (int)BLOCKING_REGION(func, &arg)) < 0) {
+	if (rb_io_wait_writable(arg.fd)) {
+	    continue;
+	}
+	rb_sys_fail("send(2)");
+    }
+    return INT2FIX(n);
+}
+
+/*
+ * call-seq:
+ *   basicsocket.do_not_reverse_lookup => true or false
+ *
+ * Gets the do_not_reverse_lookup flag of _basicsocket_.
+ *
+ *   TCPSocket.open("www.ruby-lang.org", 80) {|sock|
+ *     p sock.do_not_reverse_lookup      #=> false
+ *     p sock.peeraddr                   #=> ["AF_INET", 80, "carbon.ruby-lang.org", "221.186.184.68"]
+ *     sock.do_not_reverse_lookup = true
+ *     p sock.peeraddr                   #=> ["AF_INET", 80, "221.186.184.68", "221.186.184.68"]
+ *   }
+ */
+static VALUE
+bsock_do_not_reverse_lookup(VALUE sock)
+{
+    rb_io_t *fptr;
+
+    GetOpenFile(sock, fptr);
+    return (fptr->mode & FMODE_NOREVLOOKUP) ? Qtrue : Qfalse;
+}
+
+/*
+ * call-seq:
+ *   basicsocket.do_not_reverse_lookup = bool
+ *
+ * Sets the do_not_reverse_lookup flag of _basicsocket_.
+ *
+ *   BasicSocket.do_not_reverse_lookup = false
+ *   p TCPSocket.new("127.0.0.1", 80).do_not_reverse_lookup #=> false
+ *   BasicSocket.do_not_reverse_lookup = true
+ *   p TCPSocket.new("127.0.0.1", 80).do_not_reverse_lookup #=> true
+ *
+ */
+static VALUE
+bsock_do_not_reverse_lookup_set(VALUE sock, VALUE state)
+{
+    rb_io_t *fptr;
+
+    rb_secure(4);
+    GetOpenFile(sock, fptr);
+    if (RTEST(state)) {
+	fptr->mode |= FMODE_NOREVLOOKUP;
+    }
+    else {
+	fptr->mode &= ~FMODE_NOREVLOOKUP;
+    }
+    return sock;
+}
+
+/*
+ * call-seq:
+ *   basicsocket.recv(maxlen) => mesg
+ *   basicsocket.recv(maxlen, flags) => mesg
+ *
+ * Receives a message.
+ *
+ * _maxlen_ is the maximum number of bytes to receive.
+ *
+ * _flags_ should be a bitwise OR of Socket::MSG_* constants.
+ *
+ *   UNIXSocket.pair {|s1, s2|
+ *     s1.puts "Hello World"
+ *     p s2.recv(4)                     #=> "Hell"
+ *     p s2.recv(4, Socket::MSG_PEEK)   #=> "o Wo"
+ *     p s2.recv(4)                     #=> "o Wo"
+ *     p s2.recv(10)                    #=> "rld\n"
+ *   }
+ */
+static VALUE
+bsock_recv(int argc, VALUE *argv, VALUE sock)
+{
+    return s_recvfrom(sock, argc, argv, RECV_RECV);
+}
+
+/*
+ * call-seq:
+ * 	basicsocket.recv_nonblock(maxlen) => mesg
+ * 	basicsocket.recv_nonblock(maxlen, flags) => mesg
+ * 
+ * Receives up to _maxlen_ bytes from +socket+ using recvfrom(2) after
+ * O_NONBLOCK is set for the underlying file descriptor.
+ * _flags_ is zero or more of the +MSG_+ options.
+ * The result, _mesg_, is the data received.
+ *
+ * When recvfrom(2) returns 0, Socket#recv_nonblock returns
+ * an empty string as data.
+ * The meaning depends on the socket: EOF on TCP, empty packet on UDP, etc.
+ * 
+ * === Parameters
+ * * +maxlen+ - the number of bytes to receive from the socket
+ * * +flags+ - zero or more of the +MSG_+ options 
+ * 
+ * === Example
+ * 	serv = TCPServer.new("127.0.0.1", 0)
+ * 	af, port, host, addr = serv.addr
+ * 	c = TCPSocket.new(addr, port)
+ * 	s = serv.accept
+ * 	c.send "aaa", 0
+ * 	IO.select([s]) # emulate blocking recv.
+ * 	p s.recv_nonblock(10) #=> "aaa"
+ *
+ * Refer to Socket#recvfrom for the exceptions that may be thrown if the call
+ * to _recv_nonblock_ fails. 
+ *
+ * BasicSocket#recv_nonblock may raise any error corresponding to recvfrom(2) failure,
+ * including Errno::EWOULDBLOCK.
+ *
+ * === See
+ * * Socket#recvfrom
+ */
+
+static VALUE
+bsock_recv_nonblock(int argc, VALUE *argv, VALUE sock)
+{
+    return s_recvfrom_nonblock(sock, argc, argv, RECV_RECV);
+}
+
+/*
+ * call-seq:
+ *   BasicSocket.do_not_reverse_lookup => true or false
+ *
+ * Gets the global do_not_reverse_lookup flag.
+ *
+ *   BasicSocket.do_not_reverse_lookup  #=> false
+ */
+static VALUE
+bsock_do_not_rev_lookup(void)
+{
+    return do_not_reverse_lookup?Qtrue:Qfalse;
+}
+
+/*
+ * call-seq:
+ *   BasicSocket.do_not_reverse_lookup = bool
+ *
+ * Sets the global do_not_reverse_lookup flag.
+ *
+ * The flag is used for initial value of do_not_reverse_lookup for each socket.
+ *
+ *   s1 = TCPSocket.new("localhost", 80)
+ *   p s1.do_not_reverse_lookup                 #=> true
+ *   BasicSocket.do_not_reverse_lookup = false
+ *   s2 = TCPSocket.new("localhost", 80)
+ *   p s2.do_not_reverse_lookup                 #=> false
+ *   p s1.do_not_reverse_lookup                 #=> true
+ *
+ */
+static VALUE
+bsock_do_not_rev_lookup_set(VALUE self, VALUE val)
+{
+    rb_secure(4);
+    do_not_reverse_lookup = RTEST(val);
+    return val;
+}
+
+/*
+ * BasicSocket class
+ */
+void
+Init_basicsocket(void)
+{
+    rb_cBasicSocket = rb_define_class("BasicSocket", rb_cIO);
+    rb_undef_method(rb_cBasicSocket, "initialize");
+
+    rb_define_singleton_method(rb_cBasicSocket, "do_not_reverse_lookup",
+			       bsock_do_not_rev_lookup, 0);
+    rb_define_singleton_method(rb_cBasicSocket, "do_not_reverse_lookup=",
+			       bsock_do_not_rev_lookup_set, 1);
+    rb_define_singleton_method(rb_cBasicSocket, "for_fd", bsock_s_for_fd, 1);
+
+    rb_define_method(rb_cBasicSocket, "close_read", bsock_close_read, 0);
+    rb_define_method(rb_cBasicSocket, "close_write", bsock_close_write, 0);
+    rb_define_method(rb_cBasicSocket, "shutdown", bsock_shutdown, -1);
+    rb_define_method(rb_cBasicSocket, "setsockopt", bsock_setsockopt, 3);
+    rb_define_method(rb_cBasicSocket, "getsockopt", bsock_getsockopt, 2);
+    rb_define_method(rb_cBasicSocket, "getsockname", bsock_getsockname, 0);
+    rb_define_method(rb_cBasicSocket, "getpeername", bsock_getpeername, 0);
+    rb_define_method(rb_cBasicSocket, "local_address", bsock_local_address, 0);
+    rb_define_method(rb_cBasicSocket, "remote_address", bsock_remote_address, 0);
+    rb_define_method(rb_cBasicSocket, "send", bsock_send, -1);
+    rb_define_method(rb_cBasicSocket, "recv", bsock_recv, -1);
+    rb_define_method(rb_cBasicSocket, "recv_nonblock", bsock_recv_nonblock, -1);
+    rb_define_method(rb_cBasicSocket, "do_not_reverse_lookup", bsock_do_not_reverse_lookup, 0);
+    rb_define_method(rb_cBasicSocket, "do_not_reverse_lookup=", bsock_do_not_reverse_lookup_set, 1);
+}
diff --git a/ext/socket/constants.c b/ext/socket/constants.c
new file mode 100644
index 0000000000..7b02abecd0
--- /dev/null
+++ b/ext/socket/constants.c
@@ -0,0 +1,120 @@
+/************************************************
+
+  constants.c -
+
+  created at: Thu Mar 31 12:21:29 JST 1994
+
+  Copyright (C) 1993-2007 Yukihiro Matsumoto
+
+************************************************/
+
+#include "rubysocket.h"
+
+static void sock_define_const(const char *name, int value, VALUE mConst);
+static void sock_define_uconst(const char *name, unsigned int value, VALUE mConst);
+#define sock_define_const(name, value) sock_define_const(name, value, mConst)
+#define sock_define_uconst(name, value) sock_define_uconst(name, value, mConst)
+#include "constants.h"
+#undef sock_define_const
+#undef sock_define_uconst
+
+static int
+constant_arg(VALUE arg, int (*str_to_int)(char*, int, int*), const char *errmsg)
+{
+    VALUE tmp;
+    char *ptr;
+    int ret;
+
+    if (SYMBOL_P(arg)) {
+        arg = rb_sym_to_s(arg);
+        goto str;
+    }
+    else if (!NIL_P(tmp = rb_check_string_type(arg))) {
+	arg = tmp;
+      str:
+	rb_check_safe_obj(arg);
+        ptr = RSTRING_PTR(arg);
+        if (str_to_int(ptr, RSTRING_LEN(arg), &ret) == -1)
+	    rb_raise(rb_eSocket, "%s: %s", errmsg, ptr);
+    }
+    else {
+	ret = NUM2INT(arg);
+    }
+    return ret;
+}
+
+int
+family_arg(VALUE domain)
+{
+    /* convert AF_INET, etc. */
+    return constant_arg(domain, family_to_int, "unknown socket domain");
+}
+
+int
+socktype_arg(VALUE type)
+{
+    /* convert SOCK_STREAM, etc. */
+    return constant_arg(type, socktype_to_int, "unknown socket type");
+}
+
+int
+level_arg(VALUE level)
+{
+    /* convert SOL_SOCKET, IPPROTO_TCP, etc. */
+    return constant_arg(level, level_to_int, "unknown protocol level");
+}
+
+int
+optname_arg(int level, VALUE optname)
+{
+    switch (level) {
+      case SOL_SOCKET:
+        return constant_arg(optname, so_optname_to_int, "unknown socket level option name");
+      case IPPROTO_IP:
+        return constant_arg(optname, ip_optname_to_int, "unknown IP level option name");
+#ifdef IPPROTO_IPV6
+      case IPPROTO_IPV6:
+        return constant_arg(optname, ipv6_optname_to_int, "unknown IPv6 level option name");
+#endif
+      case IPPROTO_TCP:
+        return constant_arg(optname, tcp_optname_to_int, "unknown TCP level option name");
+      case IPPROTO_UDP:
+        return constant_arg(optname, udp_optname_to_int, "unknown UDP level option name");
+      default:
+        return NUM2INT(optname);
+    }
+}
+
+int
+shutdown_how_arg(VALUE how)
+{
+    /* convert SHUT_RD, SHUT_WR, SHUT_RDWR. */
+    return constant_arg(how, shutdown_how_to_int, "unknown shutdown argument");
+}
+
+static void
+sock_define_const(const char *name, int value, VALUE mConst)
+{
+    rb_define_const(rb_cSocket, name, INT2NUM(value));
+    rb_define_const(mConst, name, INT2NUM(value));
+}
+
+static void
+sock_define_uconst(const char *name, unsigned int value, VALUE mConst)
+{
+    rb_define_const(rb_cSocket, name, UINT2NUM(value));
+    rb_define_const(mConst, name, UINT2NUM(value));
+}
+
+/*
+ * Socket::Constants module
+ */
+void
+Init_socket_constants(void)
+{
+    VALUE mConst;
+
+    /* constants */
+    mConst = rb_define_module_under(rb_cSocket, "Constants");
+    init_constants(mConst);
+}
diff --git a/ext/socket/depend b/ext/socket/depend
index 0a9b8cacef..988cda3c7f 100644
--- a/ext/socket/depend
+++ b/ext/socket/depend
@@ -1,6 +1,20 @@
-socket.o: socket.c $(hdrdir)/ruby/ruby.h $(arch_hdrdir)/ruby/config.h \
+SOCK_HEADERS = rubysocket.h $(hdrdir)/ruby/ruby.h $(arch_hdrdir)/ruby/config.h \
 	$(hdrdir)/ruby/defines.h $(hdrdir)/ruby/io.h \
 	sockport.h constants.h
+
+init.o: init.c $(SOCK_HEADERS)
+constants.o: constants.c $(SOCK_HEADERS)
+basicsocket.o: basicsocket.c $(SOCK_HEADERS)
+socket.o: socket.c $(SOCK_HEADERS)
+ipsocket.o: ipsocket.c $(SOCK_HEADERS)
+tcpsocket.o: tcpsocket.c $(SOCK_HEADERS)
+tcpserver.o: tcpserver.c $(SOCK_HEADERS)
+sockssocket.o: sockssocket.c $(SOCK_HEADERS)
+udpsocket.o: udpsocket.c $(SOCK_HEADERS)
+unixsocket.o: unixsocket.c $(SOCK_HEADERS)
+unixserver.o: unixserver.c $(SOCK_HEADERS)
+raddrinfo.o: raddrinfo.c $(SOCK_HEADERS)
+
 getnameinfo.o: getnameinfo.c $(arch_hdrdir)/ruby/config.h addrinfo.h sockport.h
 getaddrinfo.o: getaddrinfo.c $(arch_hdrdir)/ruby/config.h addrinfo.h sockport.h
 
diff --git a/ext/socket/extconf.rb b/ext/socket/extconf.rb
index 4d9f4e43a3..718aa1f119 100644
--- a/ext/socket/extconf.rb
+++ b/ext/socket/extconf.rb
@@ -242,7 +242,20 @@ Fatal: invalid value for --with-lookup-order-hack (expected INET, INET6 or UNSPE
 EOS
 end
 
-$objs = ["socket.#{$OBJEXT}"]
+$objs = [
+  "init.#{$OBJEXT}",
+  "constants.#{$OBJEXT}",
+  "basicsocket.#{$OBJEXT}",
+  "socket.#{$OBJEXT}",
+  "ipsocket.#{$OBJEXT}",
+  "tcpsocket.#{$OBJEXT}",
+  "tcpserver.#{$OBJEXT}",
+  "sockssocket.#{$OBJEXT}",
+  "udpsocket.#{$OBJEXT}",
+  "unixsocket.#{$OBJEXT}",
+  "unixserver.#{$OBJEXT}",
+  "raddrinfo.#{$OBJEXT}"
+]
 
 unless getaddr_info_ok and have_func("getnameinfo", headers) and have_func("getaddrinfo", headers)
   if have_struct_member("struct in6_addr", "s6_addr8", headers)
diff --git a/ext/socket/init.c b/ext/socket/init.c
new file mode 100644
index 0000000000..1859777e9e
--- /dev/null
+++ b/ext/socket/init.c
@@ -0,0 +1,515 @@
+/************************************************
+
+  init.c -
+
+  created at: Thu Mar 31 12:21:29 JST 1994
+
+  Copyright (C) 1993-2007 Yukihiro Matsumoto
+
+************************************************/
+
+#include "rubysocket.h"
+
+VALUE rb_cBasicSocket;
+VALUE rb_cIPSocket;
+VALUE rb_cTCPSocket;
+VALUE rb_cTCPServer;
+VALUE rb_cUDPSocket;
+#ifdef AF_UNIX
+VALUE rb_cUNIXSocket;
+VALUE rb_cUNIXServer;
+#endif
+VALUE rb_cSocket;
+VALUE rb_cAddrInfo;
+
+VALUE rb_eSocket;
+
+#ifdef SOCKS
+VALUE rb_cSOCKSSocket;
+#endif
+
+int do_not_reverse_lookup = 0;
+
+void
+raise_socket_error(const char *reason, int error)
+{
+#ifdef EAI_SYSTEM
+    if (error == EAI_SYSTEM) rb_sys_fail(reason);
+#endif
+    rb_raise(rb_eSocket, "%s: %s", reason, gai_strerror(error));
+}
+
+VALUE
+init_sock(VALUE sock, int fd)
+{
+    rb_io_t *fp;
+
+    MakeOpenFile(sock, fp);
+    fp->fd = fd;
+    fp->mode = FMODE_READWRITE|FMODE_DUPLEX;
+    rb_io_ascii8bit_binmode(sock);
+    if (do_not_reverse_lookup) {
+	fp->mode |= FMODE_NOREVLOOKUP;
+    }
+    rb_io_synchronized(fp);
+
+    return sock;
+}
+
+VALUE
+sendto_blocking(void *data)
+{
+    struct send_arg *arg = data;
+    VALUE mesg = arg->mesg;
+    return (VALUE)sendto(arg->fd, RSTRING_PTR(mesg), RSTRING_LEN(mesg),
+                         arg->flags, arg->to, arg->tolen);
+}
+
+VALUE
+send_blocking(void *data)
+{
+    struct send_arg *arg = data;
+    VALUE mesg = arg->mesg;
+    return (VALUE)send(arg->fd, RSTRING_PTR(mesg), RSTRING_LEN(mesg),
+                       arg->flags);
+}
+
+struct recvfrom_arg {
+    int fd, flags;
+    VALUE str;
+    socklen_t alen;
+    char buf[1024];
+};
+
+static VALUE
+recvfrom_blocking(void *data)
+{
+    struct recvfrom_arg *arg = data;
+    return (VALUE)recvfrom(arg->fd, RSTRING_PTR(arg->str), RSTRING_LEN(arg->str),
+			   arg->flags, (struct sockaddr*)arg->buf, &arg->alen);
+}
+
+VALUE
+s_recvfrom(VALUE sock, int argc, VALUE *argv, enum sock_recv_type from)
+{
+    rb_io_t *fptr;
+    VALUE str, klass;
+    struct recvfrom_arg arg;
+    VALUE len, flg;
+    long buflen;
+    long slen;
+
+    rb_scan_args(argc, argv, "11", &len, &flg);
+
+    if (flg == Qnil) arg.flags = 0;
+    else             arg.flags = NUM2INT(flg);
+    buflen = NUM2INT(len);
+
+    GetOpenFile(sock, fptr);
+    if (rb_io_read_pending(fptr)) {
+	rb_raise(rb_eIOError, "recv for buffered IO");
+    }
+    arg.fd = fptr->fd;
+    arg.alen = sizeof(arg.buf);
+
+    arg.str = str = rb_tainted_str_new(0, buflen);
+    klass = RBASIC(str)->klass;
+    RBASIC(str)->klass = 0;
+
+    while (rb_io_check_closed(fptr),
+	   rb_thread_wait_fd(arg.fd),
+	   (slen = BLOCKING_REGION(recvfrom_blocking, &arg)) < 0) {
+	if (RBASIC(str)->klass || RSTRING_LEN(str) != buflen) {
+	    rb_raise(rb_eRuntimeError, "buffer string modified");
+	}
+    }
+
+    RBASIC(str)->klass = klass;
+    if (slen < RSTRING_LEN(str)) {
+	rb_str_set_len(str, slen);
+    }
+    rb_obj_taint(str);
+    switch (from) {
+      case RECV_RECV:
+	return str;
+      case RECV_IP:
+#if 0
+	if (arg.alen != sizeof(struct sockaddr_in)) {
+	    rb_raise(rb_eTypeError, "sockaddr size differs - should not happen");
+	}
+#endif
+	if (arg.alen && arg.alen != sizeof(arg.buf)) /* OSX doesn't return a from result for connection-oriented sockets */
+	    return rb_assoc_new(str, ipaddr((struct sockaddr*)arg.buf, fptr->mode & FMODE_NOREVLOOKUP));
+	else
+	    return rb_assoc_new(str, Qnil);
+
+#ifdef HAVE_SYS_UN_H
+      case RECV_UNIX:
+        return rb_assoc_new(str, unixaddr((struct sockaddr_un*)arg.buf, arg.alen));
+#endif
+      case RECV_SOCKET:
+	return rb_assoc_new(str, io_socket_addrinfo(sock, (struct sockaddr*)arg.buf, arg.alen));
+      default:
+	rb_bug("s_recvfrom called with bad value");
+    }
+}
+
+VALUE
+s_recvfrom_nonblock(VALUE sock, int argc, VALUE *argv, enum sock_recv_type from)
+{
+    rb_io_t *fptr;
+    VALUE str;
+    char buf[1024];
+    socklen_t alen = sizeof buf;
+    VALUE len, flg;
+    long buflen;
+    long slen;
+    int fd, flags;
+    VALUE addr = Qnil;
+
+    rb_scan_args(argc, argv, "11", &len, &flg);
+
+    if (flg == Qnil) flags = 0;
+    else             flags = NUM2INT(flg);
+    buflen = NUM2INT(len);
+
+#ifdef MSG_DONTWAIT
+    /* MSG_DONTWAIT avoids the race condition between fcntl and recvfrom.
+       It is not portable, though. */
+    flags |= MSG_DONTWAIT;
+#endif
+
+    GetOpenFile(sock, fptr);
+    if (rb_io_read_pending(fptr)) {
+	rb_raise(rb_eIOError, "recvfrom for buffered IO");
+    }
+    fd = fptr->fd;
+
+    str = rb_tainted_str_new(0, buflen);
+
+    rb_io_check_closed(fptr);
+    rb_io_set_nonblock(fptr);
+    slen = recvfrom(fd, RSTRING_PTR(str), buflen, flags, (struct sockaddr*)buf, &alen);
+
+    if (slen < 0) {
+	rb_sys_fail("recvfrom(2)");
+    }
+    if (slen < RSTRING_LEN(str)) {
+	rb_str_set_len(str, slen);
+    }
+    rb_obj_taint(str);
+    switch (from) {
+      case RECV_RECV:
+        return str;
+
+      case RECV_IP:
+        if (alen && alen != sizeof(buf)) /* connection-oriented socket may not return a from result */
+            addr = ipaddr((struct sockaddr*)buf, fptr->mode & FMODE_NOREVLOOKUP);
+        break;
+
+      case RECV_SOCKET:
+        addr = io_socket_addrinfo(sock, (struct sockaddr*)buf, alen);
+        break;
+
+      default:
+        rb_bug("s_recvfrom_nonblock called with bad value");
+    }
+    return rb_assoc_new(str, addr);
+}
+
+int
+ruby_socket(int domain, int type, int proto)
+{
+    int fd;
+
+    fd = socket(domain, type, proto);
+    if (fd < 0) {
+	if (errno == EMFILE || errno == ENFILE) {
+	    rb_gc();
+	    fd = socket(domain, type, proto);
+	}
+    }
+    return fd;
+}
+
+static int
+wait_connectable0(int fd, rb_fdset_t *fds_w, rb_fdset_t *fds_e)
+{
+    int sockerr;
+    socklen_t sockerrlen;
+
+    for (;;) {
+	rb_fd_zero(fds_w);
+	rb_fd_zero(fds_e);
+
+	rb_fd_set(fd, fds_w);
+	rb_fd_set(fd, fds_e);
+
+	rb_thread_select(fd+1, 0, rb_fd_ptr(fds_w), rb_fd_ptr(fds_e), 0);
+
+	if (rb_fd_isset(fd, fds_w)) {
+	    return 0;
+	}
+	else if (rb_fd_isset(fd, fds_e)) {
+	    sockerrlen = sizeof(sockerr);
+	    if (getsockopt(fd, SOL_SOCKET, SO_ERROR, (void *)&sockerr,
+			   &sockerrlen) == 0) {
+		if (sockerr == 0)
+		    continue;	/* workaround for winsock */
+		errno = sockerr;
+	    }
+	    return -1;
+	}
+    }
+
+    return 0;
+}
+
+struct wait_connectable_arg {
+    int fd;
+    rb_fdset_t fds_w;
+    rb_fdset_t fds_e;
+};
+
+#ifdef HAVE_RB_FD_INIT
+static VALUE
+try_wait_connectable(VALUE arg)
+{
+    struct wait_connectable_arg *p = (struct wait_connectable_arg *)arg;
+    return (VALUE)wait_connectable0(p->fd, &p->fds_w, &p->fds_e);
+}
+
+static VALUE
+wait_connectable_ensure(VALUE arg)
+{
+    struct wait_connectable_arg *p = (struct wait_connectable_arg *)arg;
+    rb_fd_term(&p->fds_w);
+    rb_fd_term(&p->fds_e);
+    return Qnil;
+}
+#endif
+
+static int
+wait_connectable(int fd)
+{
+    struct wait_connectable_arg arg;
+
+    rb_fd_init(&arg.fds_w);
+    rb_fd_init(&arg.fds_e);
+#ifdef HAVE_RB_FD_INIT
+    arg.fd = fd;
+    return (int)rb_ensure(try_wait_connectable, (VALUE)&arg,
+			  wait_connectable_ensure,(VALUE)&arg);
+#else
+    return wait_connectable0(fd, &arg.fds_w, &arg.fds_e);
+#endif
+}
+
+#ifdef __CYGWIN__
+#define WAIT_IN_PROGRESS 10
+#endif
+#ifdef __APPLE__
+#define WAIT_IN_PROGRESS 10
+#endif
+#ifdef __linux__
+/* returns correct error */
+#define WAIT_IN_PROGRESS 0
+#endif
+#ifndef WAIT_IN_PROGRESS
+/* BSD origin code apparently has a problem */
+#define WAIT_IN_PROGRESS 1
+#endif
+
+struct connect_arg {
+    int fd;
+    const struct sockaddr *sockaddr;
+    socklen_t len;
+};
+
+static VALUE
+connect_blocking(void *data)
+{
+    struct connect_arg *arg = data;
+    return (VALUE)connect(arg->fd, arg->sockaddr, arg->len);
+}
+
+int
+ruby_connect(int fd, const struct sockaddr *sockaddr, int len, int socks)
+{
+    int status;
+    rb_blocking_function_t *func = connect_blocking;
+    struct connect_arg arg;
+#if WAIT_IN_PROGRESS > 0
+    int wait_in_progress = -1;
+    int sockerr;
+    socklen_t sockerrlen;
+#endif
+
+    arg.fd = fd;
+    arg.sockaddr = sockaddr;
+    arg.len = len;
+#if defined(SOCKS) && !defined(SOCKS5)
+    if (socks) func = socks_connect_blocking;
+#endif
+    for (;;) {
+	status = (int)BLOCKING_REGION(func, &arg);
+	if (status < 0) {
+	    switch (errno) {
+	      case EAGAIN:
+#ifdef EINPROGRESS
+	      case EINPROGRESS:
+#endif
+#if WAIT_IN_PROGRESS > 0
+		sockerrlen = sizeof(sockerr);
+		status = getsockopt(fd, SOL_SOCKET, SO_ERROR, (void *)&sockerr, &sockerrlen);
+		if (status) break;
+		if (sockerr) {
+		    status = -1;
+		    errno = sockerr;
+		    break;
+		}
+#endif
+#ifdef EALREADY
+	      case EALREADY:
+#endif
+#if WAIT_IN_PROGRESS > 0
+		wait_in_progress = WAIT_IN_PROGRESS;
+#endif
+		status = wait_connectable(fd);
+		if (status) {
+		    break;
+		}
+		errno = 0;
+		continue;
+
+#if WAIT_IN_PROGRESS > 0
+	      case EINVAL:
+		if (wait_in_progress-- > 0) {
+		    /*
+		     * connect() after EINPROGRESS returns EINVAL on
+		     * some platforms, need to check true error
+		     * status.
+		     */
+		    sockerrlen = sizeof(sockerr);
+		    status = getsockopt(fd, SOL_SOCKET, SO_ERROR, (void *)&sockerr, &sockerrlen);
+		    if (!status && !sockerr) {
+			struct timeval tv = {0, 100000};
+			rb_thread_wait_for(tv);
+			continue;
+		    }
+		    status = -1;
+		    errno = sockerr;
+		}
+		break;
+#endif
+
+#ifdef EISCONN
+	      case EISCONN:
+		status = 0;
+		errno = 0;
+		break;
+#endif
+	      default:
+		break;
+	    }
+	}
+	return status;
+    }
+}
+
+static void
+make_fd_nonblock(int fd)
+{
+    int flags;
+#ifdef F_GETFL
+    flags = fcntl(fd, F_GETFL);
+    if (flags == -1) {
+        rb_sys_fail(0);
+    }
+#else
+    flags = 0;
+#endif
+    flags |= O_NONBLOCK;
+    if (fcntl(fd, F_SETFL, flags) == -1) {
+        rb_sys_fail(0);
+    }
+}
+
+VALUE
+s_accept_nonblock(VALUE klass, rb_io_t *fptr, struct sockaddr *sockaddr, socklen_t *len)
+{
+    int fd2;
+
+    rb_secure(3);
+    rb_io_set_nonblock(fptr);
+    fd2 = accept(fptr->fd, (struct sockaddr*)sockaddr, len);
+    if (fd2 < 0) {
+        rb_sys_fail("accept(2)");
+    }
+    make_fd_nonblock(fd2);
+    return init_sock(rb_obj_alloc(klass), fd2);
+}
+
+struct accept_arg {
+    int fd;
+    struct sockaddr *sockaddr;
+    socklen_t *len;
+};
+
+static VALUE
+accept_blocking(void *data)
+{
+    struct accept_arg *arg = data;
+    return (VALUE)accept(arg->fd, arg->sockaddr, arg->len);
+}
+
+VALUE
+s_accept(VALUE klass, int fd, struct sockaddr *sockaddr, socklen_t *len)
+{
+    int fd2;
+    int retry = 0;
+    struct accept_arg arg;
+
+    rb_secure(3);
+    arg.fd = fd;
+    arg.sockaddr = sockaddr;
+    arg.len = len;
+  retry:
+    rb_thread_wait_fd(fd);
+    fd2 = BLOCKING_REGION(accept_blocking, &arg);
+    if (fd2 < 0) {
+	switch (errno) {
+	  case EMFILE:
+	  case ENFILE:
+	    if (retry) break;
+	    rb_gc();
+	    retry = 1;
+	    goto retry;
+	  default:
+	    if (!rb_io_wait_readable(fd)) break;
+	    retry = 0;
+	    goto retry;
+	}
+	rb_sys_fail(0);
+    }
+    if (!klass) return INT2NUM(fd2);
+    return init_sock(rb_obj_alloc(klass), fd2);
+}
+
+/*
+ * SocketError is the error class for socket.
+ */
+void
+Init_socket_init()
+{
+    rb_eSocket = rb_define_class("SocketError", rb_eStandardError);
+    Init_ipsocket();
+    Init_tcpsocket();
+    Init_tcpserver();
+    Init_sockssocket();
+    Init_udpsocket();
+    Init_unixsocket();
+    Init_unixserver();
+    Init_addrinfo();
+    Init_socket_constants();
+}
diff --git a/ext/socket/ipsocket.c b/ext/socket/ipsocket.c
new file mode 100644
index 0000000000..fe687907b7
--- /dev/null
+++ b/ext/socket/ipsocket.c
@@ -0,0 +1,246 @@
+/************************************************
+
+  ipsocket.c -
+
+  created at: Thu Mar 31 12:21:29 JST 1994
+
+  Copyright (C) 1993-2007 Yukihiro Matsumoto
+
+************************************************/
+
+#include "rubysocket.h"
+
+struct inetsock_arg
+{
+    VALUE sock;
+    struct {
+	VALUE host, serv;
+	struct addrinfo *res;
+    } remote, local;
+    int type;
+    int fd;
+};
+
+static VALUE
+inetsock_cleanup(struct inetsock_arg *arg)
+{
+    if (arg->remote.res) {
+	freeaddrinfo(arg->remote.res);
+	arg->remote.res = 0;
+    }
+    if (arg->local.res) {
+	freeaddrinfo(arg->local.res);
+	arg->local.res = 0;
+    }
+    if (arg->fd >= 0) {
+	close(arg->fd);
+    }
+    return Qnil;
+}
+
+static VALUE
+init_inetsock_internal(struct inetsock_arg *arg)
+{
+    int type = arg->type;
+    struct addrinfo *res;
+    int fd, status = 0;
+    const char *syscall = 0;
+
+    arg->remote.res = sock_addrinfo(arg->remote.host, arg->remote.serv, SOCK_STREAM,
+				    (type == INET_SERVER) ? AI_PASSIVE : 0);
+    /*
+     * Maybe also accept a local address
+     */
+
+    if (type != INET_SERVER && (!NIL_P(arg->local.host) || !NIL_P(arg->local.serv))) {
+	arg->local.res = sock_addrinfo(arg->local.host, arg->local.serv, SOCK_STREAM, 0);
+    }
+
+    arg->fd = fd = -1;
+    for (res = arg->remote.res; res; res = res->ai_next) {
+	status = ruby_socket(res->ai_family,res->ai_socktype,res->ai_protocol);
+	syscall = "socket(2)";
+	fd = status;
+	if (fd < 0) {
+	    continue;
+	}
+	arg->fd = fd;
+	if (type == INET_SERVER) {
+#if !defined(_WIN32) && !defined(__CYGWIN__)
+	    status = 1;
+	    setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
+		       (char*)&status, sizeof(status));
+#endif
+	    status = bind(fd, res->ai_addr, res->ai_addrlen);
+	    syscall = "bind(2)";
+	}
+	else {
+	    if (arg->local.res) {
+		status = bind(fd, arg->local.res->ai_addr, arg->local.res->ai_addrlen);
+		syscall = "bind(2)";
+	    }
+
+	    if (status >= 0) {
+		status = ruby_connect(fd, res->ai_addr, res->ai_addrlen,
+				      (type == INET_SOCKS));
+		syscall = "connect(2)";
+	    }
+	}
+
+	if (status < 0) {
+	    close(fd);
+	    arg->fd = fd = -1;
+	    continue;
+	} else
+	    break;
+    }
+    if (status < 0) {
+	rb_sys_fail(syscall);
+    }
+
+    arg->fd = -1;
+
+    if (type == INET_SERVER)
+	listen(fd, 5);
+
+    /* create new instance */
+    return init_sock(arg->sock, fd);
+}
+
+VALUE
+init_inetsock(VALUE sock, VALUE remote_host, VALUE remote_serv,
+	      VALUE local_host, VALUE local_serv, int type)
+{
+    struct inetsock_arg arg;
+    arg.sock = sock;
+    arg.remote.host = remote_host;
+    arg.remote.serv = remote_serv;
+    arg.remote.res = 0;
+    arg.local.host = local_host;
+    arg.local.serv = local_serv;
+    arg.local.res = 0;
+    arg.type = type;
+    arg.fd = -1;
+    return rb_ensure(init_inetsock_internal, (VALUE)&arg,
+		     inetsock_cleanup, (VALUE)&arg);
+}
+
+/*
+ * call-seq:
+ *   ipsocket.addr => [address_family, port, hostname, numeric_address] 
+ *
+ * Returns the local address as an array which contains
+ * address_family, port, hostname and numeric_address. 
+ *
+ * hostname is obtained from numeric_address using reverse lookup.
+ * If ipsocket.do_not_reverse_lookup is true,
+ * hostname is same as numeric_address.
+ *
+ *   TCPSocket.open("www.ruby-lang.org", 80) {|sock|
+ *     p sock.addr #=> ["AF_INET", 49429, "hal", "192.168.0.128"]
+ *   }
+ *
+ */
+static VALUE
+ip_addr(VALUE sock)
+{
+    rb_io_t *fptr;
+    struct sockaddr_storage addr;
+    socklen_t len = sizeof addr;
+
+    GetOpenFile(sock, fptr);
+
+    if (getsockname(fptr->fd, (struct sockaddr*)&addr, &len) < 0)
+	rb_sys_fail("getsockname(2)");
+    return ipaddr((struct sockaddr*)&addr, fptr->mode & FMODE_NOREVLOOKUP);
+}
+
+/*
+ * call-seq:
+ *   ipsocket.peeraddr => [address_family, port, hostname, numeric_address] 
+ *
+ * Returns the remote address as an array which contains
+ * address_family, port, hostname and numeric_address. 
+ * It is defined for connection oritented socket such as TCPSocket.
+ *
+ *   TCPSocket.open("www.ruby-lang.org", 80) {|sock|
+ *     p sock.peeraddr #=> ["AF_INET", 80, "carbon.ruby-lang.org", "221.186.184.68"]
+ *   }
+ *
+ */
+static VALUE
+ip_peeraddr(VALUE sock)
+{
+    rb_io_t *fptr;
+    struct sockaddr_storage addr;
+    socklen_t len = sizeof addr;
+
+    GetOpenFile(sock, fptr);
+
+    if (getpeername(fptr->fd, (struct sockaddr*)&addr, &len) < 0)
+	rb_sys_fail("getpeername(2)");
+    return ipaddr((struct sockaddr*)&addr, fptr->mode & FMODE_NOREVLOOKUP);
+}
+
+/*
+ * call-seq:
+ *   ipsocket.recvfrom(maxlen)        => [mesg, ipaddr]
+ *   ipsocket.recvfrom(maxlen, flags) => [mesg, ipaddr]
+ *
+ * Receives a message and return the message as a string and
+ * an address which the message come from.
+ *
+ * _maxlen_ is the maximum number of bytes to receive.
+ *
+ * _flags_ should be a bitwise OR of Socket::MSG_* constants.
+ *
+ * ipaddr is same as IPSocket#{peeraddr,addr}.
+ *
+ *   u1 = UDPSocket.new
+ *   u1.bind("127.0.0.1", 4913)
+ *   u2 = UDPSocket.new
+ *   u2.send "uuuu", 0, "127.0.0.1", 4913
+ *   p u1.recvfrom(10) #=> ["uuuu", ["AF_INET", 33230, "localhost", "127.0.0.1"]]
+ *   
+ */
+static VALUE
+ip_recvfrom(int argc, VALUE *argv, VALUE sock)
+{
+    return s_recvfrom(sock, argc, argv, RECV_IP);
+}
+
+/*
+ * call-seq:
+ *   IPSocket.getaddress(host)        => ipaddress
+ *
+ * Lookups IP address of _host_.
+ *
+ *   IPSocket.getaddress("localhost")     #=> "127.0.0.1"
+ *   IPSocket.getaddress("ip6-localhost") #=> "::1"
+ *
+ */
+static VALUE
+ip_s_getaddress(VALUE obj, VALUE host)
+{
+    struct sockaddr_storage addr;
+    struct addrinfo *res = sock_addrinfo(host, Qnil, SOCK_STREAM, 0);
+
+    /* just take the first one */
+    memcpy(&addr, res->ai_addr, res->ai_addrlen);
+    freeaddrinfo(res);
+
+    return make_ipaddr((struct sockaddr*)&addr);
+}
+
+/*
+ * IPSocket class
+ */
+void
+Init_ipsocket(void)
+{
+    rb_cIPSocket = rb_define_class("IPSocket", rb_cBasicSocket);
+    rb_define_method(rb_cIPSocket, "addr", ip_addr, 0);
+    rb_define_method(rb_cIPSocket, "peeraddr", ip_peeraddr, 0);
+    rb_define_method(rb_cIPSocket, "recvfrom", ip_recvfrom, -1);
+    rb_define_singleton_method(rb_cIPSocket, "getaddress", ip_s_getaddress, 1);
+}
diff --git a/ext/socket/mkconstants.rb b/ext/socket/mkconstants.rb
index 84d42652a6..eca7fe6b88 100644
--- a/ext/socket/mkconstants.rb
+++ b/ext/socket/mkconstants.rb
@@ -130,7 +130,7 @@ def each_names_with_len(pat, prefix_optional=nil)
 end
 
 ERB.new(<<'EOS', nil, '%').def_method(Object, "gen_name_to_int_func_in_guard(funcname, pat, prefix_optional, guard=nil)")
-static int
+int
 <%=funcname%>(char *str, int len, int *valp)
 {
     switch (len) {
@@ -183,7 +183,7 @@ ERB.new(<<'EOS', nil, '%').def_method(Object, "gen_int_to_name_hash(hash_var, pa
 EOS
 
 ERB.new(<<'EOS', nil, '%').def_method(Object, "gen_int_to_name_func(func_name, hash_var)")
-static ID
+ID
 <%=func_name%>(int val)
 {
     st_data_t name;
diff --git a/ext/socket/raddrinfo.c b/ext/socket/raddrinfo.c
new file mode 100644
index 0000000000..e85109e401
--- /dev/null
+++ b/ext/socket/raddrinfo.c
@@ -0,0 +1,1572 @@
+/************************************************
+
+  ainfo.c -
+
+  created at: Thu Mar 31 12:21:29 JST 1994
+
+  Copyright (C) 1993-2007 Yukihiro Matsumoto
+
+************************************************/
+
+#include "rubysocket.h"
+
+#if defined(INET6) && (defined(LOOKUP_ORDER_HACK_INET) || defined(LOOKUP_ORDER_HACK_INET6))
+#define LOOKUP_ORDERS (sizeof(lookup_order_table) / sizeof(lookup_order_table[0]))
+static const int lookup_order_table[] = {
+#if defined(LOOKUP_ORDER_HACK_INET)
+    PF_INET, PF_INET6, PF_UNSPEC,
+#elif defined(LOOKUP_ORDER_HACK_INET6)
+    PF_INET6, PF_INET, PF_UNSPEC,
+#else
+    /* should not happen */
+#endif
+};
+
+static int
+ruby_getaddrinfo(const char *nodename, const char *servname,
+		 const struct addrinfo *hints, struct addrinfo **res)
+{
+    struct addrinfo tmp_hints;
+    int i, af, error;
+
+    if (hints->ai_family != PF_UNSPEC) {
+	return getaddrinfo(nodename, servname, hints, res);
+    }
+
+    for (i = 0; i < LOOKUP_ORDERS; i++) {
+	af = lookup_order_table[i];
+	MEMCPY(&tmp_hints, hints, struct addrinfo, 1);
+	tmp_hints.ai_family = af;
+	error = getaddrinfo(nodename, servname, &tmp_hints, res);
+	if (error) {
+	    if (tmp_hints.ai_family == PF_UNSPEC) {
+		break;
+	    }
+	}
+	else {
+	    break;
+	}
+    }
+
+    return error;
+}
+#define getaddrinfo(node,serv,hints,res) ruby_getaddrinfo((node),(serv),(hints),(res))
+#endif
+
+#if defined(_AIX)
+static int
+ruby_getaddrinfo__aix(const char *nodename, const char *servname,
+		      struct addrinfo *hints, struct addrinfo **res)
+{
+    int error = getaddrinfo(nodename, servname, hints, res);
+    struct addrinfo *r;
+    if (error)
+	return error;
+    for (r = *res; r != NULL; r = r->ai_next) {
+	if (r->ai_addr->sa_family == 0)
+	    r->ai_addr->sa_family = r->ai_family;
+	if (r->ai_addr->sa_len == 0)
+	    r->ai_addr->sa_len = r->ai_addrlen;
+    }
+    return 0;
+}
+#undef getaddrinfo
+#define getaddrinfo(node,serv,hints,res) ruby_getaddrinfo__aix((node),(serv),(hints),(res))
+static int
+ruby_getnameinfo__aix(const struct sockaddr *sa, size_t salen,
+		      char *host, size_t hostlen,
+		      char *serv, size_t servlen, int flags)
+{
+    struct sockaddr_in6 *sa6;
+    u_int32_t *a6;
+
+    if (sa->sa_family == AF_INET6) {
+	sa6 = (struct sockaddr_in6 *)sa;
+	a6 = sa6->sin6_addr.u6_addr.u6_addr32;
+
+	if (a6[0] == 0 && a6[1] == 0 && a6[2] == 0 && a6[3] == 0) {
+	    strncpy(host, "::", hostlen);
+	    snprintf(serv, servlen, "%d", sa6->sin6_port);
+	    return 0;
+	}
+    }
+    return getnameinfo(sa, salen, host, hostlen, serv, servlen, flags);
+}
+#undef getnameinfo
+#define getnameinfo(sa, salen, host, hostlen, serv, servlen, flags) \
+            ruby_getnameinfo__aix((sa), (salen), (host), (hostlen), (serv), (servlen), (flags))
+#endif
+
+#ifndef GETADDRINFO_EMU
+struct getaddrinfo_arg
+{
+    const char *node;
+    const char *service;
+    const struct addrinfo *hints;
+    struct addrinfo **res;
+};
+
+static VALUE
+nogvl_getaddrinfo(void *arg)
+{
+    struct getaddrinfo_arg *ptr = arg;
+    return getaddrinfo(ptr->node, ptr->service,
+                       ptr->hints, ptr->res);
+}
+#endif
+
+int
+rb_getaddrinfo(const char *node, const char *service,
+               const struct addrinfo *hints,
+               struct addrinfo **res)
+{
+#ifdef GETADDRINFO_EMU
+    return getaddrinfo(node, service, hints, res);
+#else
+    struct getaddrinfo_arg arg;
+    int ret;
+    arg.node = node;
+    arg.service = service;
+    arg.hints = hints;
+    arg.res = res;
+    ret = BLOCKING_REGION(nogvl_getaddrinfo, &arg);
+    return ret;
+#endif
+}
+
+#ifndef GETADDRINFO_EMU
+struct getnameinfo_arg
+{
+    const struct sockaddr *sa;
+    socklen_t salen;
+    char *host;
+    size_t hostlen;
+    char *serv;
+    size_t servlen;
+    int flags;
+};
+
+static VALUE
+nogvl_getnameinfo(void *arg)
+{
+    struct getnameinfo_arg *ptr = arg;
+    return getnameinfo(ptr->sa, ptr->salen,
+                       ptr->host, ptr->hostlen,
+                       ptr->serv, ptr->servlen,
+                       ptr->flags);
+}
+#endif
+
+int
+rb_getnameinfo(const struct sockaddr *sa, socklen_t salen,
+           char *host, size_t hostlen,
+           char *serv, size_t servlen, int flags)
+{
+#ifdef GETADDRINFO_EMU
+    return getnameinfo(sa, salen, host, hostlen, serv, servlen, flags);
+#else
+    struct getnameinfo_arg arg;
+    int ret;
+    arg.sa = sa;
+    arg.salen = salen;
+    arg.host = host;
+    arg.hostlen = hostlen;
+    arg.serv = serv;
+    arg.servlen = servlen;
+    arg.flags = flags;
+    ret = BLOCKING_REGION(nogvl_getnameinfo, &arg);
+    return ret;
+#endif
+}
+
+static void
+make_ipaddr0(struct sockaddr *addr, char *buf, size_t len)
+{
+    int error;
+
+    error = rb_getnameinfo(addr, SA_LEN(addr), buf, len, NULL, 0, NI_NUMERICHOST);
+    if (error) {
+        raise_socket_error("getnameinfo", error);
+    }
+}
+
+VALUE
+make_ipaddr(struct sockaddr *addr)
+{
+    char buf[1024];
+
+    make_ipaddr0(addr, buf, sizeof(buf));
+    return rb_str_new2(buf);
+}
+
+static void
+make_inetaddr(long host, char *buf, size_t len)
+{
+    struct sockaddr_in sin;
+
+    MEMZERO(&sin, struct sockaddr_in, 1);
+    sin.sin_family = AF_INET;
+    SET_SIN_LEN(&sin, sizeof(sin));
+    sin.sin_addr.s_addr = host;
+    make_ipaddr0((struct sockaddr*)&sin, buf, len);
+}
+
+static int
+str_isnumber(const char *p)
+{
+    char *ep;
+
+    if (!p || *p == '\0')
+       return 0;
+    ep = NULL;
+    (void)STRTOUL(p, &ep, 10);
+    if (ep && *ep == '\0')
+       return 1;
+    else
+       return 0;
+}
+
+static char*
+host_str(VALUE host, char *hbuf, size_t len, int *flags_ptr)
+{
+    if (NIL_P(host)) {
+        return NULL;
+    }
+    else if (rb_obj_is_kind_of(host, rb_cInteger)) {
+        unsigned long i = NUM2ULONG(host);
+
+        make_inetaddr(htonl(i), hbuf, len);
+        if (flags_ptr) *flags_ptr |= AI_NUMERICHOST;
+        return hbuf;
+    }
+    else {
+        char *name;
+
+        SafeStringValue(host);
+        name = RSTRING_PTR(host);
+        if (!name || *name == 0 || (name[0] == '<' && strcmp(name, "<any>") == 0)) {
+            make_inetaddr(INADDR_ANY, hbuf, len);
+            if (flags_ptr) *flags_ptr |= AI_NUMERICHOST;
+        }
+        else if (name[0] == '<' && strcmp(name, "<broadcast>") == 0) {
+            make_inetaddr(INADDR_BROADCAST, hbuf, len);
+            if (flags_ptr) *flags_ptr |= AI_NUMERICHOST;
+        }
+        else if (strlen(name) >= len) {
+            rb_raise(rb_eArgError, "hostname too long (%"PRIuSIZE")",
+                strlen(name));
+        }
+        else {
+            strcpy(hbuf, name);
+        }
+        return hbuf;
+    }
+}
+
+static char*
+port_str(VALUE port, char *pbuf, size_t len, int *flags_ptr)
+{
+    if (NIL_P(port)) {
+        return 0;
+    }
+    else if (FIXNUM_P(port)) {
+        snprintf(pbuf, len, "%ld", FIX2LONG(port));
+#ifdef AI_NUMERICSERV
+        if (flags_ptr) *flags_ptr |= AI_NUMERICSERV;
+#endif
+        return pbuf;
+    }
+    else {
+        char *serv;
+
+        SafeStringValue(port);
+        serv = RSTRING_PTR(port);
+        if (strlen(serv) >= len) {
+            rb_raise(rb_eArgError, "service name too long (%"PRIuSIZE")",
+                strlen(serv));
+        }
+        strcpy(pbuf, serv);
+        return pbuf;
+    }
+}
+
+struct addrinfo*
+sock_getaddrinfo(VALUE host, VALUE port, struct addrinfo *hints, int socktype_hack)
+{
+    struct addrinfo* res = NULL;
+    char *hostp, *portp;
+    int error;
+    char hbuf[NI_MAXHOST], pbuf[NI_MAXSERV];
+    int additional_flags = 0;
+
+    hostp = host_str(host, hbuf, sizeof(hbuf), &additional_flags);
+    portp = port_str(port, pbuf, sizeof(pbuf), &additional_flags);
+
+    if (socktype_hack && hints->ai_socktype == 0 && str_isnumber(portp)) {
+       hints->ai_socktype = SOCK_DGRAM;
+    }
+    hints->ai_flags |= additional_flags;
+
+    error = rb_getaddrinfo(hostp, portp, hints, &res);
+    if (error) {
+        if (hostp && hostp[strlen(hostp)-1] == '\n') {
+            rb_raise(rb_eSocket, "newline at the end of hostname");
+        }
+        raise_socket_error("getaddrinfo", error);
+    }
+
+#if defined(__APPLE__) && defined(__MACH__)
+    {
+        struct addrinfo *r;
+        r = res;
+        while (r) {
+            if (! r->ai_socktype) r->ai_socktype = hints->ai_socktype;
+            if (! r->ai_protocol) {
+                if (r->ai_socktype == SOCK_DGRAM) {
+                    r->ai_protocol = IPPROTO_UDP;
+                }
+                else if (r->ai_socktype == SOCK_STREAM) {
+                    r->ai_protocol = IPPROTO_TCP;
+                }
+            }
+            r = r->ai_next;
+        }
+    }
+#endif
+    return res;
+}
+
+struct addrinfo*
+sock_addrinfo(VALUE host, VALUE port, int socktype, int flags)
+{
+    struct addrinfo hints;
+
+    MEMZERO(&hints, struct addrinfo, 1);
+    hints.ai_family = AF_UNSPEC;
+    hints.ai_socktype = socktype;
+    hints.ai_flags = flags;
+    return sock_getaddrinfo(host, port, &hints, 1);
+}
+
+VALUE
+ipaddr(struct sockaddr *sockaddr, int norevlookup)
+{
+    VALUE family, port, addr1, addr2;
+    VALUE ary;
+    int error;
+    char hbuf[1024], pbuf[1024];
+    ID id;
+
+    id = intern_family(sockaddr->sa_family);
+    if (id) {
+        family = rb_str_dup(rb_id2str(id));
+    }
+    else {
+        sprintf(pbuf, "unknown:%d", sockaddr->sa_family);
+        family = rb_str_new2(pbuf);
+    }
+
+    addr1 = Qnil;
+    if (!norevlookup) {
+        error = rb_getnameinfo(sockaddr, SA_LEN(sockaddr), hbuf, sizeof(hbuf),
+                               NULL, 0, 0);
+        if (! error) {
+            addr1 = rb_str_new2(hbuf);
+        }
+    }
+    error = rb_getnameinfo(sockaddr, SA_LEN(sockaddr), hbuf, sizeof(hbuf),
+                           pbuf, sizeof(pbuf), NI_NUMERICHOST | NI_NUMERICSERV);
+    if (error) {
+        raise_socket_error("getnameinfo", error);
+    }
+    addr2 = rb_str_new2(hbuf);
+    if (addr1 == Qnil) {
+        addr1 = addr2;
+    }
+    port = INT2FIX(atoi(pbuf));
+    ary = rb_ary_new3(4, family, port, addr1, addr2);
+
+    return ary;
+}
+
+#ifdef HAVE_SYS_UN_H
+const char*
+unixpath(struct sockaddr_un *sockaddr, socklen_t len)
+{
+    if (sockaddr->sun_path < (char*)sockaddr + len)
+        return sockaddr->sun_path;
+    else
+        return "";
+}
+
+VALUE
+unixaddr(struct sockaddr_un *sockaddr, socklen_t len)
+{
+    return rb_assoc_new(rb_str_new2("AF_UNIX"),
+                        rb_str_new2(unixpath(sockaddr, len)));
+}
+#endif
+
+struct hostent_arg {
+    VALUE host;
+    struct addrinfo* addr;
+    VALUE (*ipaddr)(struct sockaddr*, size_t);
+};
+
+static VALUE
+make_hostent_internal(struct hostent_arg *arg)
+{
+    VALUE host = arg->host;
+    struct addrinfo* addr = arg->addr;
+    VALUE (*ipaddr)(struct sockaddr*, size_t) = arg->ipaddr;
+
+    struct addrinfo *ai;
+    struct hostent *h;
+    VALUE ary, names;
+    char **pch;
+    const char* hostp;
+    char hbuf[NI_MAXHOST];
+
+    ary = rb_ary_new();
+    if (addr->ai_canonname) {
+        hostp = addr->ai_canonname;
+    }
+    else {
+        hostp = host_str(host, hbuf, sizeof(hbuf), NULL);
+    }
+    rb_ary_push(ary, rb_str_new2(hostp));
+
+    if (addr->ai_canonname && (h = gethostbyname(addr->ai_canonname))) {
+        names = rb_ary_new();
+        if (h->h_aliases != NULL) {
+            for (pch = h->h_aliases; *pch; pch++) {
+                rb_ary_push(names, rb_str_new2(*pch));
+            }
+        }
+    }
+    else {
+        names = rb_ary_new2(0);
+    }
+    rb_ary_push(ary, names);
+    rb_ary_push(ary, INT2NUM(addr->ai_family));
+    for (ai = addr; ai; ai = ai->ai_next) {
+        rb_ary_push(ary, (*ipaddr)(ai->ai_addr, ai->ai_addrlen));
+    }
+
+    return ary;
+}
+
+VALUE
+make_hostent(VALUE host, struct addrinfo *addr, VALUE (*ipaddr)(struct sockaddr *, size_t))
+{
+    struct hostent_arg arg;
+
+    arg.host = host;
+    arg.addr = addr;
+    arg.ipaddr = ipaddr;
+    return rb_ensure(make_hostent_internal, (VALUE)&arg,
+                     RUBY_METHOD_FUNC(freeaddrinfo), (VALUE)addr);
+}
+
+typedef struct {
+    VALUE inspectname;
+    VALUE canonname;
+    int pfamily;
+    int socktype;
+    int protocol;
+    size_t sockaddr_len;
+    struct sockaddr_storage addr;
+} rb_addrinfo_t;
+
+static void
+addrinfo_mark(rb_addrinfo_t *rai)
+{
+    if (rai) {
+        rb_gc_mark(rai->inspectname);
+        rb_gc_mark(rai->canonname);
+    }
+}
+
+static void
+addrinfo_free(rb_addrinfo_t *rai)
+{
+    xfree(rai);
+}
+
+static VALUE
+addrinfo_s_allocate(VALUE klass)
+{
+    return Data_Wrap_Struct(klass, addrinfo_mark, addrinfo_free, 0);
+}
+
+#define IS_ADDRINFO(obj) (RDATA(obj)->dmark == (RUBY_DATA_FUNC)addrinfo_mark)
+static rb_addrinfo_t *
+check_addrinfo(VALUE self)
+{
+    Check_Type(self, RUBY_T_DATA);
+    if (!IS_ADDRINFO(self)) {
+        rb_raise(rb_eTypeError, "wrong argument type %s (expected AddrInfo)",
+                 rb_class2name(CLASS_OF(self)));
+    }
+    return DATA_PTR(self);
+}
+
+static rb_addrinfo_t *
+get_addrinfo(VALUE self)
+{
+    rb_addrinfo_t *rai = check_addrinfo(self);
+
+    if (!rai) {
+        rb_raise(rb_eTypeError, "uninitialized socket address");
+    }
+    return rai;
+}
+
+
+static rb_addrinfo_t *
+alloc_addrinfo()
+{
+    rb_addrinfo_t *rai = ALLOC(rb_addrinfo_t);
+    memset(rai, 0, sizeof(rb_addrinfo_t));
+    rai->inspectname = Qnil;
+    rai->canonname = Qnil;
+    return rai;
+}
+
+static void
+init_addrinfo(rb_addrinfo_t *rai, struct sockaddr *sa, size_t len,
+              int pfamily, int socktype, int protocol,
+              VALUE canonname, VALUE inspectname)
+{
+    if (sizeof(rai->addr) < len)
+        rb_raise(rb_eArgError, "sockaddr string too big");
+    memcpy((void *)&rai->addr, (void *)sa, len);
+    rai->sockaddr_len = len;
+
+    rai->pfamily = pfamily;
+    rai->socktype = socktype;
+    rai->protocol = protocol;
+    rai->canonname = canonname;
+    rai->inspectname = inspectname;
+}
+
+static VALUE
+addrinfo_new(struct sockaddr *addr, socklen_t len,
+             int family, int socktype, int protocol,
+             VALUE canonname, VALUE inspectname)
+{
+    VALUE a;
+    rb_addrinfo_t *rai;
+
+    a = addrinfo_s_allocate(rb_cAddrInfo);
+    DATA_PTR(a) = rai = alloc_addrinfo();
+    init_addrinfo(rai, addr, len, family, socktype, protocol, canonname, inspectname);
+    return a;
+}
+
+static struct addrinfo *
+call_getaddrinfo(VALUE node, VALUE service,
+                 VALUE family, VALUE socktype, VALUE protocol, VALUE flags,
+                 int socktype_hack)
+{
+    struct addrinfo hints, *res;
+
+    MEMZERO(&hints, struct addrinfo, 1);
+    hints.ai_family = NIL_P(family) ? PF_UNSPEC : family_arg(family);
+
+    if (!NIL_P(socktype)) {
+	hints.ai_socktype = socktype_arg(socktype);
+    }
+    if (!NIL_P(protocol)) {
+	hints.ai_protocol = NUM2INT(protocol);
+    }
+    if (!NIL_P(flags)) {
+	hints.ai_flags = NUM2INT(flags);
+    }
+    res = sock_getaddrinfo(node, service, &hints, socktype_hack);
+
+    if (res == NULL)
+	rb_raise(rb_eSocket, "host not found");
+    return res;
+}
+
+static void
+init_addrinfo_getaddrinfo(rb_addrinfo_t *rai, VALUE node, VALUE service,
+                          VALUE family, VALUE socktype, VALUE protocol, VALUE flags,
+                          VALUE inspectname)
+{
+    struct addrinfo *res = call_getaddrinfo(node, service, family, socktype, protocol, flags, 1);
+    VALUE canonname;
+
+    canonname = Qnil;
+    if (res->ai_canonname) {
+        canonname = rb_tainted_str_new_cstr(res->ai_canonname);
+        OBJ_FREEZE(canonname);
+    }
+
+    init_addrinfo(rai, res->ai_addr, res->ai_addrlen,
+                  NUM2INT(family), NUM2INT(socktype), NUM2INT(protocol),
+                  canonname, inspectname);
+
+    freeaddrinfo(res);
+}
+
+static VALUE
+make_inspectname(VALUE node, VALUE service)
+{
+    VALUE inspectname = Qnil;
+    if (TYPE(node) == T_STRING) {
+        inspectname = rb_str_dup(node);
+    }
+    if (TYPE(service) == T_STRING) {
+        if (NIL_P(inspectname))
+            inspectname = rb_sprintf(":%s", StringValueCStr(service));
+        else
+            rb_str_catf(inspectname, ":%s", StringValueCStr(service));
+    }
+    else if (TYPE(service) == T_FIXNUM && FIX2INT(service) != 0)
+    {
+        if (NIL_P(inspectname))
+            inspectname = rb_sprintf(":%d", FIX2INT(service));
+        else
+            rb_str_catf(inspectname, ":%d", FIX2INT(service));
+    }
+    if (!NIL_P(inspectname)) {
+        OBJ_INFECT(inspectname, node);
+        OBJ_INFECT(inspectname, service);
+        OBJ_FREEZE(inspectname);
+    }
+    return inspectname;
+}
+
+static VALUE
+addrinfo_firstonly_new(VALUE node, VALUE service, VALUE family, VALUE socktype, VALUE protocol, VALUE flags)
+{
+    VALUE ret;
+    VALUE canonname;
+    VALUE inspectname;
+
+    struct addrinfo *res = call_getaddrinfo(node, service, family, socktype, protocol, flags, 0);
+
+    inspectname = make_inspectname(node, service);
+
+    canonname = Qnil;
+    if (res->ai_canonname) {
+        canonname = rb_tainted_str_new_cstr(res->ai_canonname);
+        OBJ_FREEZE(canonname);
+    }
+
+    ret = addrinfo_new(res->ai_addr, res->ai_addrlen,
+                       res->ai_family, res->ai_socktype, res->ai_protocol,
+                       canonname, inspectname);
+
+    freeaddrinfo(res);
+    return ret;
+}
+
+static VALUE
+addrinfo_list_new(VALUE node, VALUE service, VALUE family, VALUE socktype, VALUE protocol, VALUE flags)
+{
+    VALUE ret;
+    struct addrinfo *r;
+    VALUE inspectname;
+
+    struct addrinfo *res = call_getaddrinfo(node, service, family, socktype, protocol, flags, 0);
+
+    inspectname = make_inspectname(node, service);
+
+    ret = rb_ary_new();
+    for (r = res; r; r = r->ai_next) {
+        VALUE addr;
+        VALUE canonname = Qnil;
+
+        if (r->ai_canonname) {
+            canonname = rb_tainted_str_new_cstr(r->ai_canonname);
+            OBJ_FREEZE(canonname);
+        }
+
+        addr = addrinfo_new(r->ai_addr, r->ai_addrlen,
+                            r->ai_family, r->ai_socktype, r->ai_protocol,
+                            canonname, inspectname);
+
+        rb_ary_push(ret, addr);
+    }
+
+    freeaddrinfo(res);
+    return ret;
+}
+
+
+#ifdef HAVE_SYS_UN_H
+static void
+init_unix_addrinfo(rb_addrinfo_t *rai, VALUE path)
+{
+    struct sockaddr_un un;
+
+    StringValue(path);
+
+    if (sizeof(un.sun_path) <= RSTRING_LEN(path))
+        rb_raise(rb_eArgError, "too long unix socket path (max: %dbytes)",
+            (int)sizeof(un.sun_path)-1);
+
+    MEMZERO(&un, struct sockaddr_un, 1);
+
+    un.sun_family = AF_UNIX;
+    memcpy((void*)&un.sun_path, RSTRING_PTR(path), RSTRING_LEN(path));
+   
+    init_addrinfo(rai, (struct sockaddr *)&un, sizeof(un), AF_UNIX, SOCK_STREAM, 0, Qnil, Qnil);
+}
+#endif
+
+/*
+ * call-seq:
+ *   AddrInfo.new(sockaddr)                             => addrinfo
+ *   AddrInfo.new(sockaddr, family)                     => addrinfo
+ *   AddrInfo.new(sockaddr, family, socktype)           => addrinfo
+ *   AddrInfo.new(sockaddr, family, socktype, protocol) => addrinfo
+ *
+ * returns a new instance of AddrInfo.
+ * It the instnace contains sockaddr, family, socktype, protocol.
+ * sockaddr means struct sockaddr which can be used for connect(2), etc.
+ * family, socktype and protocol are integers which is used for arguments of socket(2).
+ *
+ * sockaddr is specified as an array or a string.
+ * The array should be compatible to the value of IPSocket#addr or UNIXSocket#addr.
+ * The string should be struct sockaddr as generated by
+ * Socket.sockaddr_in or Socket.unpack_sockaddr_un.
+ *
+ * sockaddr examples:
+ * - ["AF_INET", 46102, "localhost.localdomain", "127.0.0.1"] 
+ * - ["AF_INET6", 42304, "ip6-localhost", "::1"] 
+ * - ["AF_UNIX", "/tmp/sock"] 
+ * - Socket.sockaddr_in("smtp", "2001:DB8::1")
+ * - Socket.sockaddr_in(80, "172.18.22.42")
+ * - Socket.sockaddr_in(80, "www.ruby-lang.org")
+ * - Socket.sockaddr_un("/tmp/sock")
+ *
+ * In an AF_INET/AF_INET6 sockaddr array, the 4th element,
+ * numeric IP address, is used to construct socket address in the AddrInfo instance.
+ * The 3rd element, textual host name, is also recorded but only used for AddrInfo#inspect.
+ *
+ * family is specified as an integer to specify the protocol family such as Socket::PF_INET.
+ * It can be a symbol or a string which is the constant name
+ * with or without PF_ prefix such as :INET, :INET6, :UNIX, "PF_INET", etc.
+ * If ommitted, PF_UNSPEC is assumed.
+ *
+ * socktype is specified as an integer to specify the socket type such as Socket::SOCK_STREAM.
+ * It can be a symbol or a string which is the constant name
+ * with or without SOCK_ prefix such as :STREAM, :DGRAM, :RAW, "SOCK_STREAM", etc.
+ * If ommitted, 0 is assumed.
+ *
+ * protocol is specified as an integer to specify the protocol such as Socket::IPPROTO_TCP.
+ * It must be an integer, unlike family and socktype.
+ * If ommitted, 0 is assumed.
+ * Note that 0 is reasonable value for most protocols, except raw socket.
+ *
+ */
+static VALUE
+addrinfo_initialize(int argc, VALUE *argv, VALUE self)
+{
+    rb_addrinfo_t *rai;
+    VALUE sockaddr_arg, sockaddr_ary, pfamily, socktype, protocol;
+    int i_pfamily, i_socktype, i_protocol;
+    struct sockaddr *sockaddr_ptr;
+    size_t sockaddr_len;
+    VALUE canonname = Qnil, inspectname = Qnil;
+
+    if (check_addrinfo(self))
+        rb_raise(rb_eTypeError, "already initialized socket address");
+    DATA_PTR(self) = rai = alloc_addrinfo();
+
+    rb_scan_args(argc, argv, "13", &sockaddr_arg, &pfamily, &socktype, &protocol);
+
+    i_pfamily = NIL_P(pfamily) ? PF_UNSPEC : family_arg(pfamily);
+    i_socktype = NIL_P(socktype) ? 0 : socktype_arg(socktype);
+    i_protocol = NIL_P(protocol) ? 0 : NUM2INT(protocol);
+
+    sockaddr_ary = rb_check_array_type(sockaddr_arg);
+    if (!NIL_P(sockaddr_ary)) {
+        VALUE afamily = rb_ary_entry(sockaddr_ary, 0);
+        int af;
+        StringValue(afamily);
+        if (family_to_int(RSTRING_PTR(afamily), RSTRING_LEN(afamily), &af) == -1)
+	    rb_raise(rb_eSocket, "unknown address family: %s", StringValueCStr(afamily));
+        switch (af) {
+          case AF_INET: /* ["AF_INET", 46102, "localhost.localdomain", "127.0.0.1"] */
+#ifdef INET6
+          case AF_INET6: /* ["AF_INET6", 42304, "ip6-localhost", "::1"] */
+#endif
+          {
+            VALUE service = rb_ary_entry(sockaddr_ary, 1);
+            VALUE nodename = rb_ary_entry(sockaddr_ary, 2);
+            VALUE numericnode = rb_ary_entry(sockaddr_ary, 3);
+            int flags;
+
+            service = INT2NUM(NUM2INT(service));
+            if (!NIL_P(nodename))
+                StringValue(nodename);
+            StringValue(numericnode);
+            flags = AI_NUMERICHOST;
+#ifdef AI_NUMERICSERV
+            flags |= AI_NUMERICSERV;
+#endif
+
+            init_addrinfo_getaddrinfo(rai, numericnode, service,
+                    INT2NUM(i_pfamily ? i_pfamily : af), INT2NUM(i_socktype), INT2NUM(i_protocol),
+                    INT2NUM(flags),
+                    rb_str_equal(numericnode, nodename) ? Qnil : make_inspectname(nodename, service));
+            break;
+          }
+
+#ifdef HAVE_SYS_UN_H
+          case AF_UNIX: /* ["AF_UNIX", "/tmp/sock"] */
+          {
+            VALUE path = rb_ary_entry(sockaddr_ary, 1);
+            StringValue(path);
+            init_unix_addrinfo(rai, path);
+            break;
+          }
+#endif
+
+          default:
+            rb_raise(rb_eSocket, "unexpected address family");
+        }
+    }
+    else {
+        StringValue(sockaddr_arg);
+        sockaddr_ptr = (struct sockaddr *)RSTRING_PTR(sockaddr_arg);
+        sockaddr_len = RSTRING_LEN(sockaddr_arg);
+        init_addrinfo(rai, sockaddr_ptr, sockaddr_len,
+                      i_pfamily, i_socktype, i_protocol,
+                      canonname, inspectname);
+    }
+
+    return self;
+}
+
+static int
+get_afamily(struct sockaddr *addr, socklen_t len)
+{
+    if ((char*)&addr->sa_family + sizeof(addr->sa_family) - (char*)addr <= len)
+        return addr->sa_family;
+    else
+        return AF_UNSPEC;
+}
+
+static int
+ai_get_afamily(rb_addrinfo_t *rai)
+{
+    return get_afamily((struct sockaddr *)&rai->addr, rai->sockaddr_len);
+}
+
+/*
+ * call-seq:
+ *   addrinfo.inspect => string
+ *
+ * returns a string which shows addrinfo in human-readable form.
+ *
+ *   AddrInfo.tcp("localhost", 80).inspect #=> "#<AddrInfo: 127.0.0.1:80 TCP (localhost:80)>"
+ *   AddrInfo.unix("/tmp/sock").inspect    #=> "#<AddrInfo: /tmp/sock SOCK_STREAM>"
+ *
+ */
+static VALUE
+addrinfo_inspect(VALUE self)
+{
+    rb_addrinfo_t *rai = get_addrinfo(self);
+    int internet_p;
+    VALUE ret;
+
+    ret = rb_sprintf("#<%s: ", rb_obj_classname(self));
+
+    if (rai->sockaddr_len == 0) {
+        rb_str_cat2(ret, "empty-sockaddr");
+    }
+    else if (rai->sockaddr_len < ((char*)&rai->addr.ss_family + sizeof(rai->addr.ss_family)) - (char*)&rai->addr)
+        rb_str_cat2(ret, "too-short-sockaddr");
+    else {
+        switch (rai->addr.ss_family) {
+          case AF_INET:
+          {
+            struct sockaddr_in *addr;
+            int port;
+            if (rai->sockaddr_len < sizeof(struct sockaddr_in)) {
+                rb_str_cat2(ret, "too-short-AF_INET-sockaddr");
+            }
+            else {
+                addr = (struct sockaddr_in *)&rai->addr;
+                rb_str_catf(ret, "%d.%d.%d.%d",
+                            ((unsigned char*)&addr->sin_addr)[0],
+                            ((unsigned char*)&addr->sin_addr)[1],
+                            ((unsigned char*)&addr->sin_addr)[2],
+                            ((unsigned char*)&addr->sin_addr)[3]);
+                port = ntohs(addr->sin_port);
+                if (port)
+                    rb_str_catf(ret, ":%d", port);
+                if (sizeof(struct sockaddr_in) < rai->sockaddr_len)
+                    rb_str_catf(ret, "(sockaddr %d bytes too long)", (int)(rai->sockaddr_len - sizeof(struct sockaddr_in)));
+            }
+            break;
+          }
+
+#ifdef INET6
+          case AF_INET6:
+          {
+            struct sockaddr_in6 *addr;
+            char hbuf[1024];
+            int port;
+            int error;
+            if (rai->sockaddr_len < sizeof(struct sockaddr_in6)) {
+                rb_str_cat2(ret, "too-short-AF_INET6-sockaddr");
+            }
+            else {
+                addr = (struct sockaddr_in6 *)&rai->addr;
+                /* use getnameinfo for scope_id.
+                 * RFC 4007: IPv6 Scoped Address Architecture
+                 * draft-ietf-ipv6-scope-api-00.txt: Scoped Address Extensions to the IPv6 Basic Socket API
+                 */
+                error = getnameinfo((struct sockaddr *)&rai->addr, rai->sockaddr_len,
+                                    hbuf, sizeof(hbuf), NULL, 0,
+                                    NI_NUMERICHOST|NI_NUMERICSERV);
+                if (error) {
+                    raise_socket_error("getnameinfo", error);
+                }
+                if (addr->sin6_port == 0) {
+                    rb_str_cat2(ret, hbuf);
+                }
+                else {
+                    port = ntohs(addr->sin6_port);
+                    rb_str_catf(ret, "[%s]:%d", hbuf, port);
+                }
+                if (sizeof(struct sockaddr_in6) < rai->sockaddr_len)
+                    rb_str_catf(ret, "(sockaddr %d bytes too long)", (int)(rai->sockaddr_len - sizeof(struct sockaddr_in6)));
+            }
+            break;
+          }
+#endif
+
+#ifdef HAVE_SYS_UN_H
+          case AF_UNIX:
+          {
+            struct sockaddr_un *addr = (struct sockaddr_un *)&rai->addr;
+            char *p, *s, *t, *e;
+            s = addr->sun_path;
+            e = (char*)addr + rai->sockaddr_len;
+            if (e < s)
+                rb_str_cat2(ret, "too-short-AF_UNIX-sockaddr");
+            else if (s == e)
+                rb_str_cat2(ret, "empty-path-AF_UNIX-sockaddr");
+            else {
+                int printable_only = 1;
+                p = s;
+                while (p < e && *p != '\0') {
+                    printable_only = printable_only && ISPRINT(*p) && !ISSPACE(*p);
+                    p++;
+                }
+                t = p;
+                while (p < e && *p == '\0')
+                    p++;
+                if (printable_only && /* only printable, no space */
+                    t < e && /* NUL terminated */
+                    p == e) { /* no data after NUL */
+		    if (s == t)
+			rb_str_cat2(ret, "empty-path-AF_UNIX-sockaddr");
+		    else if (s[0] == '/') /* absolute path */
+			rb_str_cat2(ret, s);
+		    else
+                        rb_str_catf(ret, "AF_UNIX %s", s);
+                }
+                else {
+                    rb_str_cat2(ret, "AF_UNIX");
+                    e = (char *)addr->sun_path + sizeof(addr->sun_path);
+                    while (s < e && *(e-1) == '\0')
+                        e--;
+                    while (s < e)
+                        rb_str_catf(ret, ":%02x", (unsigned char)*s++);
+                }
+                if (addr->sun_path + sizeof(addr->sun_path) < (char*)&rai->addr + rai->sockaddr_len)
+                    rb_str_catf(ret, "(sockaddr %d bytes too long)",
+                            (int)(rai->sockaddr_len - (addr->sun_path + sizeof(addr->sun_path) - (char*)&rai->addr)));
+            }
+            break;
+          }
+#endif
+
+          default:
+          {
+            ID id = intern_family(rai->addr.ss_family);
+            if (id == 0)
+                rb_str_catf(ret, "unknown address family %d", rai->addr.ss_family);
+            else
+                rb_str_catf(ret, "%s address format unknown", rb_id2name(id));
+            break;
+          }
+        }
+    }
+
+    if (rai->pfamily && ai_get_afamily(rai) != rai->pfamily) {
+        ID id = intern_protocol_family(rai->pfamily);
+        if (id)
+            rb_str_catf(ret, " %s", rb_id2name(id));
+        else
+            rb_str_catf(ret, " PF_\?\?\?(%d)", rai->pfamily);
+    }
+
+    internet_p = rai->pfamily == PF_INET;
+#ifdef INET6
+    internet_p = internet_p || rai->pfamily == PF_INET6;
+#endif
+    if (internet_p && rai->socktype == SOCK_STREAM &&
+        (rai->protocol == 0 || rai->protocol == IPPROTO_TCP)) {
+        rb_str_cat2(ret, " TCP");
+    }
+    else if (internet_p && rai->socktype == SOCK_DGRAM &&
+        (rai->protocol == 0 || rai->protocol == IPPROTO_UDP)) {
+        rb_str_cat2(ret, " UDP");
+    }
+    else {
+        if (rai->socktype) {
+            ID id = intern_socktype(rai->socktype);
+            if (id)
+                rb_str_catf(ret, " %s", rb_id2name(id));
+            else
+                rb_str_catf(ret, " SOCK_\?\?\?(%d)", rai->socktype);
+        }
+
+        if (rai->protocol) {
+            if (internet_p) {
+                ID id = intern_ipproto(rai->protocol);
+                if (id)
+                    rb_str_catf(ret, " %s", rb_id2name(id));
+                else
+                    goto unknown_protocol;
+            }
+            else {
+              unknown_protocol:
+                rb_str_catf(ret, " UNKNOWN_PROTOCOL(%d)", rai->protocol);
+            }
+        }
+    }
+
+    if (!NIL_P(rai->canonname)) {
+        VALUE name = rai->canonname;
+        rb_str_catf(ret, " %s", StringValueCStr(name));
+    }
+
+    if (!NIL_P(rai->inspectname)) {
+        VALUE name = rai->inspectname;
+        rb_str_catf(ret, " (%s)", StringValueCStr(name));
+    }
+
+    rb_str_buf_cat2(ret, ">");
+    return ret;
+}
+
+/*
+ * call-seq:
+ *   addrinfo.afamily => integer
+ *
+ * returns the address family as an integer.
+ *
+ *   AddrInfo.tcp("localhost", 80).afamily == Socket::AF_INET #=> true
+ *
+ */
+static VALUE
+addrinfo_afamily(VALUE self)
+{
+    rb_addrinfo_t *rai = get_addrinfo(self);
+    return INT2NUM(ai_get_afamily(rai));
+}
+
+/*
+ * call-seq:
+ *   addrinfo.pfamily => integer
+ *
+ * returns the protocol family as an integer.
+ *
+ *   AddrInfo.tcp("localhost", 80).pfamily == Socket::PF_INET #=> true
+ *
+ */
+static VALUE
+addrinfo_pfamily(VALUE self)
+{
+    rb_addrinfo_t *rai = get_addrinfo(self);
+    return INT2NUM(rai->pfamily);
+}
+
+/*
+ * call-seq:
+ *   addrinfo.socktype => integer
+ *
+ * returns the socket type as an integer.
+ *
+ *   AddrInfo.tcp("localhost", 80).socktype == Socket::SOCK_STREAM #=> true
+ *
+ */
+static VALUE
+addrinfo_socktype(VALUE self)
+{
+    rb_addrinfo_t *rai = get_addrinfo(self);
+    return INT2NUM(rai->socktype);
+}
+
+/*
+ * call-seq:
+ *   addrinfo.protocol => integer
+ *
+ * returns the socket type as an integer.
+ *
+ *   AddrInfo.tcp("localhost", 80).protocol == Socket::IPPROTO_TCP #=> true
+ *
+ */
+static VALUE
+addrinfo_protocol(VALUE self)
+{
+    rb_addrinfo_t *rai = get_addrinfo(self);
+    return INT2NUM(rai->protocol);
+}
+
+/*
+ * call-seq:
+ *   addrinfo.to_sockaddr => string
+ *
+ * returns the socket address as packed struct sockaddr string.
+ *
+ *   AddrInfo.tcp("localhost", 80).to_sockaddr                    
+ *   #=> "\x02\x00\x00P\x7F\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00"
+ *
+ */
+static VALUE
+addrinfo_to_sockaddr(VALUE self)
+{
+    rb_addrinfo_t *rai = get_addrinfo(self);
+    VALUE ret;
+    ret = rb_str_new((char*)&rai->addr, rai->sockaddr_len);
+    OBJ_INFECT(ret, self);
+    return ret;
+}
+
+/*
+ * call-seq:
+ *   addrinfo.canonname => string or nil
+ *
+ * returns the canonical name as an string.
+ *
+ * nil is returned if no canonical name.
+ *
+ * The canonical name is set by AddrInfo.getaddrinfo when AI_CANONNAME is specified.
+ *
+ *   list = AddrInfo.getaddrinfo("www.ruby-lang.org", 80, :INET, :STREAM, nil, Socket::AI_CANONNAME)
+ *   p list[0] #=> #<AddrInfo: 221.186.184.68:80 TCP carbon.ruby-lang.org (www.ruby-lang.org:80)>
+ *   p list[0].canonname #=> "carbon.ruby-lang.org"
+ *
+ */
+static VALUE
+addrinfo_canonname(VALUE self)
+{
+    rb_addrinfo_t *rai = get_addrinfo(self);
+    return rai->canonname;
+}
+
+#ifdef AF_INET6
+# define IS_IP_FAMILY(af) ((af) == AF_INET || (af) == AF_INET6)
+#else
+# define IS_IP_FAMILY(af) ((af) == AF_INET)
+#endif
+
+/*
+ * call-seq:
+ *   addrinfo.ip? => true or false
+ *
+ * returns true if addrinfo is internet (IPv4/IPv6) address.
+ * returns false otherwise.
+ *
+ *   AddrInfo.tcp("127.0.0.1", 80).ip? #=> true
+ *   AddrInfo.tcp("::1", 80).ip?       #=> true
+ *   AddrInfo.unix("/tmp/sock").ip?    #=> false
+ *
+ */
+static VALUE
+addrinfo_ip_p(VALUE self)
+{
+    rb_addrinfo_t *rai = get_addrinfo(self);
+    int family = ai_get_afamily(rai);
+    return IS_IP_FAMILY(family) ? Qtrue : Qfalse;
+}
+
+/*
+ * call-seq:
+ *   addrinfo.ipv4? => true or false
+ *
+ * returns true if addrinfo is IPv4 address.
+ * returns false otherwise.
+ *
+ *   AddrInfo.tcp("127.0.0.1", 80).ipv4? #=> true
+ *   AddrInfo.tcp("::1", 80).ipv4?       #=> false
+ *   AddrInfo.unix("/tmp/sock").ipv4?    #=> false
+ *
+ */
+static VALUE
+addrinfo_ipv4_p(VALUE self)
+{
+    rb_addrinfo_t *rai = get_addrinfo(self);
+    return ai_get_afamily(rai) == AF_INET ? Qtrue : Qfalse;
+}
+
+/*
+ * call-seq:
+ *   addrinfo.ipv6? => true or false
+ *
+ * returns true if addrinfo is IPv6 address.
+ * returns false otherwise.
+ *
+ *   AddrInfo.tcp("127.0.0.1", 80).ipv6? #=> false
+ *   AddrInfo.tcp("::1", 80).ipv6?       #=> true
+ *   AddrInfo.unix("/tmp/sock").ipv6?    #=> false
+ *
+ */
+static VALUE
+addrinfo_ipv6_p(VALUE self)
+{
+#ifdef AF_INET6
+    rb_addrinfo_t *rai = get_addrinfo(self);
+    return ai_get_afamily(rai) == AF_INET6 ? Qtrue : Qfalse;
+#else
+    return Qfalse;
+#endif
+}
+
+/*
+ * call-seq:
+ *   addrinfo.unix? => true or false
+ *
+ * returns true if addrinfo is UNIX address.
+ * returns false otherwise.
+ *
+ *   AddrInfo.tcp("127.0.0.1", 80).unix? #=> false
+ *   AddrInfo.tcp("::1", 80).unix?       #=> false
+ *   AddrInfo.unix("/tmp/sock").unix?    #=> true
+ *
+ */
+static VALUE
+addrinfo_unix_p(VALUE self)
+{
+    rb_addrinfo_t *rai = get_addrinfo(self);
+#ifdef AF_UNIX
+    return ai_get_afamily(rai) == AF_UNIX ? Qtrue : Qfalse;
+#else
+    return Qfalse;
+#endif
+}
+
+/*
+ * call-seq:
+ *   addrinfo.getnameinfo        => [nodename, service]
+ *   addrinfo.getnameinfo(flags) => [nodename, service]
+ *
+ * returns nodename and service as a pair of strings.
+ * This converts struct sockaddr in addrinfo to textual representation.
+ *
+ * flags should be bitwise OR of Socket::NI_??? constants.
+ *
+ *   AddrInfo.tcp("127.0.0.1", 80).getnameinfo #=> ["localhost", "www"]
+ *
+ *   AddrInfo.tcp("127.0.0.1", 80).getnameinfo(Socket::NI_NUMERICSERV)
+ *   #=> ["localhost", "80"]
+ */
+static VALUE
+addrinfo_getnameinfo(int argc, VALUE *argv, VALUE self)
+{
+    rb_addrinfo_t *rai = get_addrinfo(self);
+    VALUE vflags;
+    char hbuf[1024], pbuf[1024];
+    int flags, error;
+
+    rb_scan_args(argc, argv, "01", &vflags);
+
+    flags = NIL_P(vflags) ? 0 : NUM2INT(vflags);
+
+    if (rai->socktype == SOCK_DGRAM)
+        flags |= NI_DGRAM;
+
+    error = getnameinfo((struct sockaddr *)&rai->addr, rai->sockaddr_len,
+                        hbuf, sizeof(hbuf), pbuf, sizeof(pbuf),
+                        flags);
+    if (error) {
+        raise_socket_error("getnameinfo", error);
+    }
+
+    return rb_assoc_new(rb_str_new2(hbuf), rb_str_new2(pbuf));
+}
+
+/*
+ * call-seq:
+ *   addrinfo.ip_unpack => [addr, port]
+ *
+ * Returns the IP address and port number as 2-element array.
+ *
+ *   AddrInfo.tcp("127.0.0.1", 80).ip_unpack    #=> ["127.0.0.1", 80]
+ *   AddrInfo.tcp("::1", 80).ip_unpack          #=> ["::1", 80]
+ */
+static VALUE
+addrinfo_ip_unpack(VALUE self)
+{
+    rb_addrinfo_t *rai = get_addrinfo(self);
+    int family = ai_get_afamily(rai);
+    VALUE vflags;
+    VALUE ret, portstr;
+
+    if (!IS_IP_FAMILY(family))
+	rb_raise(rb_eSocket, "need IPv4 or IPv6 address");
+
+    vflags = INT2NUM(NI_NUMERICHOST|NI_NUMERICSERV);
+    ret = addrinfo_getnameinfo(1, &vflags, self);
+    portstr = rb_ary_entry(ret, 1);
+    rb_ary_store(ret, 1, INT2NUM(atoi(StringValueCStr(portstr))));
+    return ret;
+}
+
+#ifdef HAVE_SYS_UN_H
+/*
+ * call-seq:
+ *   addrinfo.unix_path => path
+ *
+ * Returns the socket path as a string.
+ *
+ *   AddrInfo.unix("/tmp/sock").unix_path       #=> "/tmp/sock"
+ */
+static VALUE
+addrinfo_unix_path(VALUE self)
+{
+    rb_addrinfo_t *rai = get_addrinfo(self);
+    int family = ai_get_afamily(rai);
+    struct sockaddr_un *addr;
+    char *s, *e;
+
+    if (family != AF_UNIX)
+	rb_raise(rb_eSocket, "need AF_UNIX address");
+
+    addr = (struct sockaddr_un *)&rai->addr;
+
+    s = addr->sun_path;
+    e = (char*)addr + rai->sockaddr_len;
+    if (e < s)
+        rb_raise(rb_eSocket, "too short AF_UNIX address");
+    if (addr->sun_path + sizeof(addr->sun_path) < e)
+        rb_raise(rb_eSocket, "too long AF_UNIX address");
+    while (s < e && *(e-1) == '\0')
+        e--;
+    return rb_str_new(s, e-s);
+}
+#endif
+
+/*
+ * call-seq:
+ *   AddrInfo.getaddrinfo(nodename, service, family, socktype, protocol, flags) => [addrinfo, ...]
+ *   AddrInfo.getaddrinfo(nodename, service, family, socktype, protocol)        => [addrinfo, ...]
+ *   AddrInfo.getaddrinfo(nodename, service, family, socktype)                  => [addrinfo, ...]
+ *   AddrInfo.getaddrinfo(nodename, service, family)                            => [addrinfo, ...]
+ *   AddrInfo.getaddrinfo(nodename, service)                                    => [addrinfo, ...]
+ *
+ * returns a list of addrinfo objects as an array.
+ *
+ * This method converts nodename (hostname) and service (port) to addrinfo.
+ * Since the conversion is not unique, the result is a list of addrinfo objects.
+ *
+ * nodename or service can be nil if no conversion intended.
+ *
+ * family, socktype and protocol are hint for prefered protocol.
+ * If the result will be used for a socket with SOCK_STREAM, 
+ * SOCK_STREAM should be specified as socktype.
+ * If so, AddrInfo.getaddrinfo returns addrinfo list appropriate for SOCK_STREAM.
+ * If they are omitted or nil is given, the result is not restricted.
+ * 
+ * Similary, PF_INET6 as family restricts for IPv6.
+ *
+ * flags should be bitwise OR of Socket::AI_??? constants.
+ *
+ *   AddrInfo.getaddrinfo("www.kame.net", 80, nil, :STREAM)
+ *   #=> [#<AddrInfo: 203.178.141.194:80 TCP (www.kame.net:80)>,
+ *   #    #<AddrInfo: [2001:200:0:8002:203:47ff:fea5:3085]:80 TCP (www.kame.net:80)>]
+ *
+ */
+static VALUE
+addrinfo_s_getaddrinfo(int argc, VALUE *argv, VALUE self)
+{
+    VALUE node, service, family, socktype, protocol, flags;
+
+    rb_scan_args(argc, argv, "24", &node, &service, &family, &socktype, &protocol, &flags);
+    return addrinfo_list_new(node, service, family, socktype, protocol, flags);
+}
+
+
+/*
+ * call-seq:
+ *   AddrInfo.ip(host) => addrinfo
+ *
+ * returns an addrinfo object for IP address.
+ *
+ *   AddrInfo.ip("localhost") #=> #<AddrInfo: 127.0.0.1 (localhost)>
+ */
+static VALUE
+addrinfo_s_ip(VALUE self, VALUE host)
+{
+    VALUE ret;
+    rb_addrinfo_t *rai;
+    ret = addrinfo_firstonly_new(host, Qnil,
+            INT2NUM(PF_UNSPEC), INT2FIX(0), INT2FIX(0), INT2FIX(0));
+    rai = get_addrinfo(ret);
+    rai->socktype = 0;
+    rai->protocol = 0;
+    return ret;
+}
+
+/*
+ * call-seq:
+ *   AddrInfo.tcp(host, port) => addrinfo
+ *
+ * returns an addrinfo object for TCP address.
+ *
+ *   AddrInfo.tcp("localhost", "smtp") #=> #<AddrInfo: 127.0.0.1:25 TCP (localhost:smtp)>
+ */
+static VALUE
+addrinfo_s_tcp(VALUE self, VALUE host, VALUE port)
+{
+    return addrinfo_firstonly_new(host, port,
+            INT2NUM(PF_UNSPEC), INT2NUM(SOCK_STREAM), INT2NUM(IPPROTO_TCP), INT2FIX(0));
+}
+
+/*
+ * call-seq:
+ *   AddrInfo.udp(host, port) => addrinfo
+ *
+ * returns an addrinfo object for UDP address.
+ *
+ *   AddrInfo.udp("localhost", "daytime") #=> #<AddrInfo: 127.0.0.1:13 UDP (localhost:daytime)>
+ */
+static VALUE
+addrinfo_s_udp(VALUE self, VALUE host, VALUE port)
+{
+    return addrinfo_firstonly_new(host, port,
+            INT2NUM(PF_UNSPEC), INT2NUM(SOCK_DGRAM), INT2NUM(IPPROTO_UDP), INT2FIX(0));
+}
+
+#ifdef HAVE_SYS_UN_H
+
+/*
+ * call-seq:
+ *   AddrInfo.udp(host, port) => addrinfo
+ *
+ * returns an addrinfo object for UNIX socket address.
+ *
+ *   AddrInfo.unix("/tmp/sock") #=> #<AddrInfo: /tmp/sock SOCK_STREAM>
+ */
+static VALUE
+addrinfo_s_unix(VALUE self, VALUE path)
+{
+    VALUE addr;
+    rb_addrinfo_t *rai;
+
+    addr = addrinfo_s_allocate(rb_cAddrInfo);
+    DATA_PTR(addr) = rai = alloc_addrinfo();
+    init_unix_addrinfo(rai, path);
+    OBJ_INFECT(addr, path);
+    return addr;
+}
+
+#endif
+
+VALUE
+sockaddr_string_value(volatile VALUE *v)
+{
+    VALUE val = *v;
+    if (TYPE(val) == RUBY_T_DATA && IS_ADDRINFO(val)) {
+        *v = addrinfo_to_sockaddr(val);
+    }
+    StringValue(*v);
+    return *v;
+}
+
+char *
+sockaddr_string_value_ptr(volatile VALUE *v)
+{
+    sockaddr_string_value(v);
+    return RSTRING_PTR(*v);
+}
+
+VALUE
+fd_socket_addrinfo(int fd, struct sockaddr *addr, socklen_t len)
+{
+    int family;
+    int socktype;
+    int ret;
+    socklen_t optlen = sizeof(socktype);
+
+    /* assumes protocol family and address family are identical */
+    family = get_afamily(addr, len);
+
+    ret = getsockopt(fd, SOL_SOCKET, SO_TYPE, (void*)&socktype, &optlen);
+    if (ret == -1) {
+        rb_sys_fail("getsockopt(SO_TYPE)");
+    }
+
+    return addrinfo_new(addr, len, family, socktype, 0, Qnil, Qnil);
+}
+
+VALUE
+io_socket_addrinfo(VALUE io, struct sockaddr *addr, socklen_t len)
+{
+    rb_io_t *fptr;
+
+    switch (TYPE(io)) {
+      case T_FIXNUM:
+        return fd_socket_addrinfo(FIX2INT(io), addr, len);
+
+      case T_BIGNUM:
+        return fd_socket_addrinfo(NUM2INT(io), addr, len);
+
+      case T_FILE:
+        GetOpenFile(io, fptr);
+        return fd_socket_addrinfo(fptr->fd, addr, len);
+
+      default:
+        rb_raise(rb_eTypeError, "neither IO nor file descriptor");
+    }
+}
+
+/*
+ * AddrInfo class
+ */
+void
+Init_addrinfo(void)
+{
+    rb_cAddrInfo = rb_define_class("AddrInfo", rb_cData);
+    rb_define_alloc_func(rb_cAddrInfo, addrinfo_s_allocate);
+    rb_define_method(rb_cAddrInfo, "initialize", addrinfo_initialize, -1);
+    rb_define_method(rb_cAddrInfo, "inspect", addrinfo_inspect, 0);
+    rb_define_singleton_method(rb_cAddrInfo, "getaddrinfo", addrinfo_s_getaddrinfo, -1);
+    rb_define_singleton_method(rb_cAddrInfo, "ip", addrinfo_s_ip, 1);
+    rb_define_singleton_method(rb_cAddrInfo, "tcp", addrinfo_s_tcp, 2);
+    rb_define_singleton_method(rb_cAddrInfo, "udp", addrinfo_s_udp, 2);
+#ifdef HAVE_SYS_UN_H
+    rb_define_singleton_method(rb_cAddrInfo, "unix", addrinfo_s_unix, 1);
+#endif
+
+    rb_define_method(rb_cAddrInfo, "afamily", addrinfo_afamily, 0);
+    rb_define_method(rb_cAddrInfo, "pfamily", addrinfo_pfamily, 0);
+    rb_define_method(rb_cAddrInfo, "socktype", addrinfo_socktype, 0);
+    rb_define_method(rb_cAddrInfo, "protocol", addrinfo_protocol, 0);
+    rb_define_method(rb_cAddrInfo, "canonname", addrinfo_canonname, 0);
+
+    rb_define_method(rb_cAddrInfo, "ip?", addrinfo_ip_p, 0);
+    rb_define_method(rb_cAddrInfo, "ip_unpack", addrinfo_ip_unpack, 0);
+    rb_define_method(rb_cAddrInfo, "ipv4?", addrinfo_ipv4_p, 0);
+    rb_define_method(rb_cAddrInfo, "ipv6?", addrinfo_ipv6_p, 0);
+    rb_define_method(rb_cAddrInfo, "unix?", addrinfo_unix_p, 0);
+#ifdef HAVE_SYS_UN_H
+    rb_define_method(rb_cAddrInfo, "unix_path", addrinfo_unix_path, 0);
+#endif
+
+    rb_define_method(rb_cAddrInfo, "to_sockaddr", addrinfo_to_sockaddr, 0);
+
+    rb_define_method(rb_cAddrInfo, "getnameinfo", addrinfo_getnameinfo, -1);
+}
diff --git a/ext/socket/rubysocket.h b/ext/socket/rubysocket.h
new file mode 100644
index 0000000000..9f6116016b
--- /dev/null
+++ b/ext/socket/rubysocket.h
@@ -0,0 +1,228 @@
+#ifndef RUBY_SOCKET_H
+#define RUBY_SOCKET_H 1
+
+#include "ruby/ruby.h"
+#include "ruby/io.h"
+#include "ruby/util.h"
+#include <stdio.h>
+#include <sys/types.h>
+
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#ifdef HAVE_SYS_UIO_H
+#include <sys/uio.h>
+#endif
+
+#ifdef HAVE_XTI_H
+#include <xti.h>
+#endif
+
+#ifndef _WIN32
+#if defined(__BEOS__) && !defined(__HAIKU__) && !defined(BONE)
+# include <net/socket.h>
+#else
+# include <sys/socket.h>
+#endif
+#include <netinet/in.h>
+#ifdef HAVE_NETINET_IN_SYSTM_H
+# include <netinet/in_systm.h>
+#endif
+#ifdef HAVE_NETINET_TCP_H
+# include <netinet/tcp.h>
+#endif
+#ifdef HAVE_NETINET_UDP_H
+# include <netinet/udp.h>
+#endif
+#ifdef HAVE_ARPA_INET_H
+# include <arpa/inet.h>
+#endif
+#include <netdb.h>
+#endif
+#include <errno.h>
+#ifdef HAVE_SYS_UN_H
+#include <sys/un.h>
+#endif
+
+#if defined(HAVE_FCNTL)
+#ifdef HAVE_SYS_SELECT_H
+#include <sys/select.h>
+#endif
+#ifdef HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+#ifdef HAVE_SYS_TIME_H
+#include <sys/time.h>
+#endif
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+#endif
+#ifndef EWOULDBLOCK
+#define EWOULDBLOCK EAGAIN
+#endif
+#ifndef HAVE_GETADDRINFO
+# include "addrinfo.h"
+#endif
+#include "sockport.h"
+
+#ifndef NI_MAXHOST
+# define NI_MAXHOST 1025
+#endif
+#ifndef NI_MAXSERV
+# define NI_MAXSERV 32
+#endif
+
+#ifndef HAVE_SOCKADDR_STORAGE
+/*
+ * RFC 2553: protocol-independent placeholder for socket addresses
+ */
+#define _SS_MAXSIZE     128
+#define _SS_ALIGNSIZE   (sizeof(double))
+#define _SS_PAD1SIZE    (_SS_ALIGNSIZE - sizeof(unsigned char) * 2)
+#define _SS_PAD2SIZE    (_SS_MAXSIZE - sizeof(unsigned char) * 2 - \
+                                _SS_PAD1SIZE - _SS_ALIGNSIZE)
+
+struct sockaddr_storage {
+#ifdef HAVE_SA_LEN
+        unsigned char ss_len;           /* address length */
+        unsigned char ss_family;        /* address family */
+#else
+        unsigned short ss_family;
+#endif
+        char    __ss_pad1[_SS_PAD1SIZE];
+        double  __ss_align;     /* force desired structure storage alignment */
+        char    __ss_pad2[_SS_PAD2SIZE];
+};
+#endif
+
+#if defined(_AIX)
+#ifndef CMSG_SPACE
+# define CMSG_SPACE(len) (_CMSG_ALIGN(sizeof(struct cmsghdr)) + _CMSG_ALIGN(len))
+#endif
+#ifndef CMSG_LEN
+# define CMSG_LEN(len) (_CMSG_ALIGN(sizeof(struct cmsghdr)) + (len))
+#endif
+#endif
+
+#ifdef __BEOS__
+#undef close
+#define close closesocket
+#endif
+
+#define INET_CLIENT 0
+#define INET_SERVER 1
+#define INET_SOCKS  2
+
+extern int do_not_reverse_lookup;
+#define FMODE_NOREVLOOKUP 0x100
+
+extern VALUE rb_cBasicSocket;
+extern VALUE rb_cIPSocket;
+extern VALUE rb_cTCPSocket;
+extern VALUE rb_cTCPServer;
+extern VALUE rb_cUDPSocket;
+#ifdef AF_UNIX
+extern VALUE rb_cUNIXSocket;
+extern VALUE rb_cUNIXServer;
+#endif
+extern VALUE rb_cSocket;
+extern VALUE rb_cAddrInfo;
+
+extern VALUE rb_eSocket;
+
+#ifdef SOCKS
+extern VALUE rb_cSOCKSSocket;
+#ifdef SOCKS5
+#include <socks.h>
+#else
+void SOCKSinit();
+int Rconnect();
+#endif
+#endif
+
+
+#define BLOCKING_REGION(func, arg) (long)rb_thread_blocking_region((func), (arg), RUBY_UBF_IO, 0)
+
+#define SockAddrStringValue(v) sockaddr_string_value(&(v))
+#define SockAddrStringValuePtr(v) sockaddr_string_value_ptr(&(v))
+VALUE sockaddr_string_value(volatile VALUE *);
+char *sockaddr_string_value_ptr(volatile VALUE *);
+
+NORETURN(void raise_socket_error(const char *, int));
+
+int family_to_int(char *str, int len, int *valp);
+
+int family_arg(VALUE domain);
+int socktype_arg(VALUE type);
+int level_arg(VALUE level);
+int optname_arg(int level, VALUE optname);
+int shutdown_how_arg(VALUE how);
+
+ID intern_protocol_family(int val);
+ID intern_socktype(int val);
+ID intern_ipproto(int val);
+ID intern_family(int val);
+
+int rb_getaddrinfo(const char *node, const char *service, const struct addrinfo *hints, struct addrinfo **res);
+int rb_getnameinfo(const struct sockaddr *sa, socklen_t salen, char *host, size_t hostlen, char *serv, size_t servlen, int flags);
+struct addrinfo *sock_addrinfo(VALUE host, VALUE port, int socktype, int flags);
+struct addrinfo* sock_getaddrinfo(VALUE host, VALUE port, struct addrinfo *hints, int socktype_hack);
+VALUE fd_socket_addrinfo(int fd, struct sockaddr *addr, socklen_t len);
+VALUE io_socket_addrinfo(VALUE io, struct sockaddr *addr, socklen_t len);
+
+VALUE make_ipaddr(struct sockaddr *addr);
+VALUE ipaddr(struct sockaddr *sockaddr, int norevlookup);
+VALUE make_hostent(VALUE host, struct addrinfo *addr, VALUE (*ipaddr)(struct sockaddr *, size_t));
+
+const char* unixpath(struct sockaddr_un *sockaddr, socklen_t len);
+VALUE unixaddr(struct sockaddr_un *sockaddr, socklen_t len);
+
+int ruby_socket(int domain, int type, int proto);
+VALUE init_sock(VALUE sock, int fd);
+VALUE sock_s_socketpair(VALUE klass, VALUE domain, VALUE type, VALUE protocol);
+VALUE init_inetsock(VALUE sock, VALUE remote_host, VALUE remote_serv, VALUE local_host, VALUE local_serv, int type);
+VALUE init_unixsock(VALUE sock, VALUE path, int server);
+
+struct send_arg {
+    int fd, flags;
+    VALUE mesg;
+    struct sockaddr *to;
+    socklen_t tolen;
+};
+
+VALUE sendto_blocking(void *data);
+VALUE send_blocking(void *data);
+VALUE bsock_send(int argc, VALUE *argv, VALUE sock);
+
+enum sock_recv_type {
+    RECV_RECV,                  /* BasicSocket#recv(no from) */
+    RECV_IP,                    /* IPSocket#recvfrom */
+    RECV_UNIX,                  /* UNIXSocket#recvfrom */
+    RECV_SOCKET                 /* Socket#recvfrom */
+};
+
+VALUE s_recvfrom_nonblock(VALUE sock, int argc, VALUE *argv, enum sock_recv_type from);
+VALUE s_recvfrom(VALUE sock, int argc, VALUE *argv, enum sock_recv_type from);
+
+int ruby_connect(int fd, const struct sockaddr *sockaddr, int len, int socks);
+
+VALUE sock_listen(VALUE sock, VALUE log);
+
+VALUE s_accept(VALUE klass, int fd, struct sockaddr *sockaddr, socklen_t *len);
+VALUE s_accept_nonblock(VALUE klass, rb_io_t *fptr, struct sockaddr *sockaddr, socklen_t *len);
+
+void Init_basicsocket(void);
+void Init_ipsocket(void);
+void Init_tcpsocket(void);
+void Init_tcpserver(void);
+void Init_sockssocket(void);
+void Init_udpsocket(void);
+void Init_unixsocket(void);
+void Init_unixserver(void);
+void Init_socket_constants(void);
+void Init_addrinfo(void);
+void Init_socket_init(void);
+
+#endif
diff --git a/ext/socket/socket.c b/ext/socket/socket.c
index 221a857d5c..def79ba535 100644
--- a/ext/socket/socket.c
+++ b/ext/socket/socket.c
@@ -2,4050 +2,13 @@
 
   socket.c -
 
-  $Author$
   created at: Thu Mar 31 12:21:29 JST 1994
 
   Copyright (C) 1993-2007 Yukihiro Matsumoto
 
 ************************************************/
 
-#include "ruby/ruby.h"
-#include "ruby/io.h"
-#include "ruby/util.h"
-#include <stdio.h>
-#include <sys/types.h>
-
-#ifdef HAVE_UNISTD_H
-#include <unistd.h>
-#endif
-
-#ifdef HAVE_SYS_UIO_H
-#include <sys/uio.h>
-#endif
-
-#ifdef HAVE_XTI_H
-#include <xti.h>
-#endif
-
-#ifndef _WIN32
-#if defined(__BEOS__) && !defined(__HAIKU__) && !defined(BONE)
-# include <net/socket.h>
-#else
-# include <sys/socket.h>
-#endif
-#include <netinet/in.h>
-#ifdef HAVE_NETINET_IN_SYSTM_H
-# include <netinet/in_systm.h>
-#endif
-#ifdef HAVE_NETINET_TCP_H
-# include <netinet/tcp.h>
-#endif
-#ifdef HAVE_NETINET_UDP_H
-# include <netinet/udp.h>
-#endif
-#ifdef HAVE_ARPA_INET_H
-# include <arpa/inet.h>
-#endif
-#include <netdb.h>
-#endif
-#include <errno.h>
-#ifdef HAVE_SYS_UN_H
-#include <sys/un.h>
-#endif
-
-#if defined(HAVE_FCNTL)
-#ifdef HAVE_SYS_SELECT_H
-#include <sys/select.h>
-#endif
-#ifdef HAVE_SYS_TYPES_H
-#include <sys/types.h>
-#endif
-#ifdef HAVE_SYS_TIME_H
-#include <sys/time.h>
-#endif
-#ifdef HAVE_FCNTL_H
-#include <fcntl.h>
-#endif
-#endif
-#ifndef EWOULDBLOCK
-#define EWOULDBLOCK EAGAIN
-#endif
-#ifndef HAVE_GETADDRINFO
-# include "addrinfo.h"
-#endif
-#include "sockport.h"
-
-static int do_not_reverse_lookup = 0;
-#define FMODE_NOREVLOOKUP 0x100
-
-VALUE rb_cBasicSocket;
-VALUE rb_cIPSocket;
-VALUE rb_cTCPSocket;
-VALUE rb_cTCPServer;
-VALUE rb_cUDPSocket;
-#ifdef AF_UNIX
-VALUE rb_cUNIXSocket;
-VALUE rb_cUNIXServer;
-#endif
-VALUE rb_cSocket;
-static VALUE rb_cAddrInfo;
-
-static VALUE rb_eSocket;
-
-#ifdef SOCKS
-VALUE rb_cSOCKSSocket;
-#ifdef SOCKS5
-#include <socks.h>
-#else
-void SOCKSinit();
-int Rconnect();
-#endif
-#endif
-
-#define BLOCKING_REGION(func, arg) (long)rb_thread_blocking_region((func), (arg), RUBY_UBF_IO, 0)
-
-#define INET_CLIENT 0
-#define INET_SERVER 1
-#define INET_SOCKS  2
-
-#ifndef HAVE_SOCKADDR_STORAGE
-/*
- * RFC 2553: protocol-independent placeholder for socket addresses
- */
-#define _SS_MAXSIZE	128
-#define _SS_ALIGNSIZE	(sizeof(double))
-#define _SS_PAD1SIZE	(_SS_ALIGNSIZE - sizeof(unsigned char) * 2)
-#define _SS_PAD2SIZE	(_SS_MAXSIZE - sizeof(unsigned char) * 2 - \
-				_SS_PAD1SIZE - _SS_ALIGNSIZE)
-
-struct sockaddr_storage {
-#ifdef HAVE_SA_LEN
-	unsigned char ss_len;		/* address length */
-	unsigned char ss_family;	/* address family */
-#else
-	unsigned short ss_family;
-#endif
-	char	__ss_pad1[_SS_PAD1SIZE];
-	double	__ss_align;	/* force desired structure storage alignment */
-	char	__ss_pad2[_SS_PAD2SIZE];
-};
-#endif
-
-static void sock_define_const(const char *name, int value, VALUE mConst);
-static void sock_define_uconst(const char *name, unsigned int value, VALUE mConst);
-#define sock_define_const(name, value) sock_define_const(name, value, mConst)
-#define sock_define_uconst(name, value) sock_define_uconst(name, value, mConst)
-#include "constants.h"
-#undef sock_define_const
-#undef sock_define_uconst
-
-NORETURN(static void raise_socket_error(const char *, int));
-
-#if defined(INET6) && (defined(LOOKUP_ORDER_HACK_INET) || defined(LOOKUP_ORDER_HACK_INET6))
-#define LOOKUP_ORDERS (sizeof(lookup_order_table) / sizeof(lookup_order_table[0]))
-static const int lookup_order_table[] = {
-#if defined(LOOKUP_ORDER_HACK_INET)
-    PF_INET, PF_INET6, PF_UNSPEC,
-#elif defined(LOOKUP_ORDER_HACK_INET6)
-    PF_INET6, PF_INET, PF_UNSPEC,
-#else
-    /* should not happen */
-#endif
-};
-
-static int
-ruby_getaddrinfo(const char *nodename, const char *servname,
-		 const struct addrinfo *hints, struct addrinfo **res)
-{
-    struct addrinfo tmp_hints;
-    int i, af, error;
-
-    if (hints->ai_family != PF_UNSPEC) {
-	return getaddrinfo(nodename, servname, hints, res);
-    }
-
-    for (i = 0; i < LOOKUP_ORDERS; i++) {
-	af = lookup_order_table[i];
-	MEMCPY(&tmp_hints, hints, struct addrinfo, 1);
-	tmp_hints.ai_family = af;
-	error = getaddrinfo(nodename, servname, &tmp_hints, res);
-	if (error) {
-	    if (tmp_hints.ai_family == PF_UNSPEC) {
-		break;
-	    }
-	}
-	else {
-	    break;
-	}
-    }
-
-    return error;
-}
-#define getaddrinfo(node,serv,hints,res) ruby_getaddrinfo((node),(serv),(hints),(res))
-#endif
-
-#if defined(_AIX)
-static int
-ruby_getaddrinfo__aix(const char *nodename, const char *servname,
-		      struct addrinfo *hints, struct addrinfo **res)
-{
-    int error = getaddrinfo(nodename, servname, hints, res);
-    struct addrinfo *r;
-    if (error)
-	return error;
-    for (r = *res; r != NULL; r = r->ai_next) {
-	if (r->ai_addr->sa_family == 0)
-	    r->ai_addr->sa_family = r->ai_family;
-	if (r->ai_addr->sa_len == 0)
-	    r->ai_addr->sa_len = r->ai_addrlen;
-    }
-    return 0;
-}
-#undef getaddrinfo
-#define getaddrinfo(node,serv,hints,res) ruby_getaddrinfo__aix((node),(serv),(hints),(res))
-static int
-ruby_getnameinfo__aix(const struct sockaddr *sa, size_t salen,
-		      char *host, size_t hostlen,
-		      char *serv, size_t servlen, int flags)
-{
-    struct sockaddr_in6 *sa6;
-    u_int32_t *a6;
-
-    if (sa->sa_family == AF_INET6) {
-	sa6 = (struct sockaddr_in6 *)sa;
-	a6 = sa6->sin6_addr.u6_addr.u6_addr32;
-
-	if (a6[0] == 0 && a6[1] == 0 && a6[2] == 0 && a6[3] == 0) {
-	    strncpy(host, "::", hostlen);
-	    snprintf(serv, servlen, "%d", sa6->sin6_port);
-	    return 0;
-	}
-    }
-    return getnameinfo(sa, salen, host, hostlen, serv, servlen, flags);
-}
-#undef getnameinfo
-#define getnameinfo(sa, salen, host, hostlen, serv, servlen, flags) \
-            ruby_getnameinfo__aix((sa), (salen), (host), (hostlen), (serv), (servlen), (flags))
-
-#ifndef CMSG_SPACE
-# define CMSG_SPACE(len) (_CMSG_ALIGN(sizeof(struct cmsghdr)) + _CMSG_ALIGN(len))
-#endif
-#ifndef CMSG_LEN
-# define CMSG_LEN(len) (_CMSG_ALIGN(sizeof(struct cmsghdr)) + (len))
-#endif
-#endif
-
-#ifdef __BEOS__
-#undef close
-#define close closesocket
-#endif
-
-#ifndef GETADDRINFO_EMU
-struct getaddrinfo_arg
-{
-    const char *node;
-    const char *service;
-    const struct addrinfo *hints;
-    struct addrinfo **res;
-};
-
-static VALUE
-nogvl_getaddrinfo(void *arg)
-{
-    struct getaddrinfo_arg *ptr = arg;
-    return getaddrinfo(ptr->node, ptr->service,
-                       ptr->hints, ptr->res);
-}
-#endif
-
-static int
-rb_getaddrinfo(const char *node, const char *service,
-               const struct addrinfo *hints,
-               struct addrinfo **res)
-{
-#ifdef GETADDRINFO_EMU
-    return getaddrinfo(node, service, hints, res);
-#else
-    struct getaddrinfo_arg arg;
-    int ret;
-    arg.node = node;
-    arg.service = service;
-    arg.hints = hints;
-    arg.res = res;
-    ret = BLOCKING_REGION(nogvl_getaddrinfo, &arg);
-    return ret;
-#endif
-}
-
-#ifndef GETADDRINFO_EMU
-struct getnameinfo_arg
-{
-    const struct sockaddr *sa;
-    socklen_t salen;
-    char *host;
-    size_t hostlen;
-    char *serv;
-    size_t servlen;
-    int flags;
-};
-
-static VALUE
-nogvl_getnameinfo(void *arg)
-{
-    struct getnameinfo_arg *ptr = arg;
-    return getnameinfo(ptr->sa, ptr->salen,
-                       ptr->host, ptr->hostlen,
-                       ptr->serv, ptr->servlen,
-                       ptr->flags);
-}
-#endif
-
-static int
-rb_getnameinfo(const struct sockaddr *sa, socklen_t salen,
-           char *host, size_t hostlen,
-           char *serv, size_t servlen, int flags)
-{
-#ifdef GETADDRINFO_EMU
-    return getnameinfo(sa, salen, host, hostlen, serv, servlen, flags);
-#else
-    struct getnameinfo_arg arg;
-    int ret;
-    arg.sa = sa;
-    arg.salen = salen;
-    arg.host = host;
-    arg.hostlen = hostlen;
-    arg.serv = serv;
-    arg.servlen = servlen;
-    arg.flags = flags;
-    ret = BLOCKING_REGION(nogvl_getnameinfo, &arg);
-    return ret;
-#endif
-}
-
-static int
-constant_arg(VALUE arg, int (*str_to_int)(char*, int, int*), const char *errmsg)
-{
-    VALUE tmp;
-    char *ptr;
-    int ret;
-
-    if (SYMBOL_P(arg)) {
-        arg = rb_sym_to_s(arg);
-        goto str;
-    }
-    else if (!NIL_P(tmp = rb_check_string_type(arg))) {
-	arg = tmp;
-      str:
-	rb_check_safe_obj(arg);
-        ptr = RSTRING_PTR(arg);
-        if (str_to_int(ptr, RSTRING_LEN(arg), &ret) == -1)
-	    rb_raise(rb_eSocket, "%s: %s", errmsg, ptr);
-    }
-    else {
-	ret = NUM2INT(arg);
-    }
-    return ret;
-}
-
-static int
-family_arg(VALUE domain)
-{
-    /* convert AF_INET, etc. */
-    return constant_arg(domain, family_to_int, "unknown socket domain");
-}
-
-static int
-socktype_arg(VALUE type)
-{
-    /* convert SOCK_STREAM, etc. */
-    return constant_arg(type, socktype_to_int, "unknown socket type");
-}
-
-static int
-level_arg(VALUE level)
-{
-    /* convert SOL_SOCKET, IPPROTO_TCP, etc. */
-    return constant_arg(level, level_to_int, "unknown protocol level");
-}
-
-static int
-optname_arg(int level, VALUE optname)
-{
-    switch (level) {
-      case SOL_SOCKET:
-        return constant_arg(optname, so_optname_to_int, "unknown socket level option name");
-      case IPPROTO_IP:
-        return constant_arg(optname, ip_optname_to_int, "unknown IP level option name");
-#ifdef IPPROTO_IPV6
-      case IPPROTO_IPV6:
-        return constant_arg(optname, ipv6_optname_to_int, "unknown IPv6 level option name");
-#endif
-      case IPPROTO_TCP:
-        return constant_arg(optname, tcp_optname_to_int, "unknown TCP level option name");
-      case IPPROTO_UDP:
-        return constant_arg(optname, udp_optname_to_int, "unknown UDP level option name");
-      default:
-        return NUM2INT(optname);
-    }
-}
-
-static int
-shutdown_how_arg(VALUE how)
-{
-    /* convert SHUT_RD, SHUT_WR, SHUT_RDWR. */
-    return constant_arg(how, shutdown_how_to_int, "unknown shutdown argument");
-}
-
-typedef struct {
-    VALUE inspectname;
-    VALUE canonname;
-    int pfamily;
-    int socktype;
-    int protocol;
-    size_t sockaddr_len;
-    struct sockaddr_storage addr;
-} rb_addrinfo_t;
-
-static void
-addrinfo_mark(rb_addrinfo_t *rai)
-{
-    if (rai) {
-        rb_gc_mark(rai->inspectname);
-        rb_gc_mark(rai->canonname);
-    }
-}
-
-static void
-addrinfo_free(rb_addrinfo_t *rai)
-{
-    xfree(rai);
-}
-
-static VALUE
-addrinfo_s_allocate(VALUE klass)
-{
-    return Data_Wrap_Struct(klass, addrinfo_mark, addrinfo_free, 0);
-}
-
-#define IS_ADDRINFO(obj) (RDATA(obj)->dmark == (RUBY_DATA_FUNC)addrinfo_mark)
-static rb_addrinfo_t *
-check_addrinfo(VALUE self)
-{
-    Check_Type(self, RUBY_T_DATA);
-    if (!IS_ADDRINFO(self)) {
-        rb_raise(rb_eTypeError, "wrong argument type %s (expected AddrInfo)",
-                 rb_class2name(CLASS_OF(self)));
-    }
-    return DATA_PTR(self);
-}
-
-static rb_addrinfo_t *
-get_addrinfo(VALUE self)
-{
-    rb_addrinfo_t *rai = check_addrinfo(self);
-
-    if (!rai) {
-        rb_raise(rb_eTypeError, "uninitialized socket address");
-    }
-    return rai;
-}
-
-
-static rb_addrinfo_t *
-alloc_addrinfo()
-{
-    rb_addrinfo_t *rai = ALLOC(rb_addrinfo_t);
-    memset(rai, 0, sizeof(rb_addrinfo_t));
-    rai->inspectname = Qnil;
-    rai->canonname = Qnil;
-    return rai;
-}
-
-static void
-init_addrinfo(rb_addrinfo_t *rai, struct sockaddr *sa, size_t len,
-              int pfamily, int socktype, int protocol,
-              VALUE canonname, VALUE inspectname)
-{
-    if (sizeof(rai->addr) < len)
-        rb_raise(rb_eArgError, "sockaddr string too big");
-    memcpy((void *)&rai->addr, (void *)sa, len);
-    rai->sockaddr_len = len;
-
-    rai->pfamily = pfamily;
-    rai->socktype = socktype;
-    rai->protocol = protocol;
-    rai->canonname = canonname;
-    rai->inspectname = inspectname;
-}
-
-static VALUE
-addrinfo_new(struct sockaddr *addr, socklen_t len,
-             int family, int socktype, int protocol,
-             VALUE canonname, VALUE inspectname)
-{
-    VALUE a;
-    rb_addrinfo_t *rai;
-
-    a = addrinfo_s_allocate(rb_cAddrInfo);
-    DATA_PTR(a) = rai = alloc_addrinfo();
-    init_addrinfo(rai, addr, len, family, socktype, protocol, canonname, inspectname);
-    return a;
-}
-
-static struct addrinfo* sock_getaddrinfo(VALUE host, VALUE port, struct addrinfo *hints, int socktype_hack);
-
-static struct addrinfo *
-call_getaddrinfo(VALUE node, VALUE service,
-                 VALUE family, VALUE socktype, VALUE protocol, VALUE flags,
-                 int socktype_hack)
-{
-    struct addrinfo hints, *res;
-
-    MEMZERO(&hints, struct addrinfo, 1);
-    hints.ai_family = NIL_P(family) ? PF_UNSPEC : family_arg(family);
-
-    if (!NIL_P(socktype)) {
-	hints.ai_socktype = socktype_arg(socktype);
-    }
-    if (!NIL_P(protocol)) {
-	hints.ai_protocol = NUM2INT(protocol);
-    }
-    if (!NIL_P(flags)) {
-	hints.ai_flags = NUM2INT(flags);
-    }
-    res = sock_getaddrinfo(node, service, &hints, socktype_hack);
-
-    if (res == NULL)
-	rb_raise(rb_eSocket, "host not found");
-    return res;
-}
-
-static void
-init_addrinfo_getaddrinfo(rb_addrinfo_t *rai, VALUE node, VALUE service,
-                          VALUE family, VALUE socktype, VALUE protocol, VALUE flags,
-                          VALUE inspectname)
-{
-    struct addrinfo *res = call_getaddrinfo(node, service, family, socktype, protocol, flags, 1);
-    VALUE canonname;
-
-    canonname = Qnil;
-    if (res->ai_canonname) {
-        canonname = rb_tainted_str_new_cstr(res->ai_canonname);
-        OBJ_FREEZE(canonname);
-    }
-
-    init_addrinfo(rai, res->ai_addr, res->ai_addrlen,
-                  NUM2INT(family), NUM2INT(socktype), NUM2INT(protocol),
-                  canonname, inspectname);
-
-    freeaddrinfo(res);
-}
-
-static VALUE
-make_inspectname(VALUE node, VALUE service)
-{
-    VALUE inspectname = Qnil;
-    if (TYPE(node) == T_STRING) {
-        inspectname = rb_str_dup(node);
-    }
-    if (TYPE(service) == T_STRING) {
-        if (NIL_P(inspectname))
-            inspectname = rb_sprintf(":%s", StringValueCStr(service));
-        else
-            rb_str_catf(inspectname, ":%s", StringValueCStr(service));
-    }
-    else if (TYPE(service) == T_FIXNUM && FIX2INT(service) != 0)
-    {
-        if (NIL_P(inspectname))
-            inspectname = rb_sprintf(":%d", FIX2INT(service));
-        else
-            rb_str_catf(inspectname, ":%d", FIX2INT(service));
-    }
-    if (!NIL_P(inspectname)) {
-        OBJ_INFECT(inspectname, node);
-        OBJ_INFECT(inspectname, service);
-        OBJ_FREEZE(inspectname);
-    }
-    return inspectname;
-}
-
-static VALUE
-addrinfo_firstonly_new(VALUE node, VALUE service, VALUE family, VALUE socktype, VALUE protocol, VALUE flags)
-{
-    VALUE ret;
-    VALUE canonname;
-    VALUE inspectname;
-
-    struct addrinfo *res = call_getaddrinfo(node, service, family, socktype, protocol, flags, 0);
-
-    inspectname = make_inspectname(node, service);
-
-    canonname = Qnil;
-    if (res->ai_canonname) {
-        canonname = rb_tainted_str_new_cstr(res->ai_canonname);
-        OBJ_FREEZE(canonname);
-    }
-
-    ret = addrinfo_new(res->ai_addr, res->ai_addrlen,
-                       res->ai_family, res->ai_socktype, res->ai_protocol,
-                       canonname, inspectname);
-
-    freeaddrinfo(res);
-    return ret;
-}
-
-static VALUE
-addrinfo_list_new(VALUE node, VALUE service, VALUE family, VALUE socktype, VALUE protocol, VALUE flags)
-{
-    VALUE ret;
-    struct addrinfo *r;
-    VALUE inspectname;
-
-    struct addrinfo *res = call_getaddrinfo(node, service, family, socktype, protocol, flags, 0);
-
-    inspectname = make_inspectname(node, service);
-
-    ret = rb_ary_new();
-    for (r = res; r; r = r->ai_next) {
-        VALUE addr;
-        VALUE canonname = Qnil;
-
-        if (r->ai_canonname) {
-            canonname = rb_tainted_str_new_cstr(r->ai_canonname);
-            OBJ_FREEZE(canonname);
-        }
-
-        addr = addrinfo_new(r->ai_addr, r->ai_addrlen,
-                            r->ai_family, r->ai_socktype, r->ai_protocol,
-                            canonname, inspectname);
-
-        rb_ary_push(ret, addr);
-    }
-
-    freeaddrinfo(res);
-    return ret;
-}
-
-
-#ifdef HAVE_SYS_UN_H
-static void
-init_unix_addrinfo(rb_addrinfo_t *rai, VALUE path)
-{
-    struct sockaddr_un un;
-
-    StringValue(path);
-
-    if (sizeof(un.sun_path) <= RSTRING_LEN(path))
-        rb_raise(rb_eArgError, "too long unix socket path (max: %dbytes)",
-            (int)sizeof(un.sun_path)-1);
-
-    MEMZERO(&un, struct sockaddr_un, 1);
-
-    un.sun_family = AF_UNIX;
-    memcpy((void*)&un.sun_path, RSTRING_PTR(path), RSTRING_LEN(path));
-   
-    init_addrinfo(rai, (struct sockaddr *)&un, sizeof(un), AF_UNIX, SOCK_STREAM, 0, Qnil, Qnil);
-}
-#endif
-
-/*
- * call-seq:
- *   AddrInfo.new(sockaddr)                             => addrinfo
- *   AddrInfo.new(sockaddr, family)                     => addrinfo
- *   AddrInfo.new(sockaddr, family, socktype)           => addrinfo
- *   AddrInfo.new(sockaddr, family, socktype, protocol) => addrinfo
- *
- * returns a new instance of AddrInfo.
- * It the instnace contains sockaddr, family, socktype, protocol.
- * sockaddr means struct sockaddr which can be used for connect(2), etc.
- * family, socktype and protocol are integers which is used for arguments of socket(2).
- *
- * sockaddr is specified as an array or a string.
- * The array should be compatible to the value of IPSocket#addr or UNIXSocket#addr.
- * The string should be struct sockaddr as generated by
- * Socket.sockaddr_in or Socket.unpack_sockaddr_un.
- *
- * sockaddr examples:
- * - ["AF_INET", 46102, "localhost.localdomain", "127.0.0.1"] 
- * - ["AF_INET6", 42304, "ip6-localhost", "::1"] 
- * - ["AF_UNIX", "/tmp/sock"] 
- * - Socket.sockaddr_in("smtp", "2001:DB8::1")
- * - Socket.sockaddr_in(80, "172.18.22.42")
- * - Socket.sockaddr_in(80, "www.ruby-lang.org")
- * - Socket.sockaddr_un("/tmp/sock")
- *
- * In an AF_INET/AF_INET6 sockaddr array, the 4th element,
- * numeric IP address, is used to construct socket address in the AddrInfo instance.
- * The 3rd element, textual host name, is also recorded but only used for AddrInfo#inspect.
- *
- * family is specified as an integer to specify the protocol family such as Socket::PF_INET.
- * It can be a symbol or a string which is the constant name
- * with or without PF_ prefix such as :INET, :INET6, :UNIX, "PF_INET", etc.
- * If ommitted, PF_UNSPEC is assumed.
- *
- * socktype is specified as an integer to specify the socket type such as Socket::SOCK_STREAM.
- * It can be a symbol or a string which is the constant name
- * with or without SOCK_ prefix such as :STREAM, :DGRAM, :RAW, "SOCK_STREAM", etc.
- * If ommitted, 0 is assumed.
- *
- * protocol is specified as an integer to specify the protocol such as Socket::IPPROTO_TCP.
- * It must be an integer, unlike family and socktype.
- * If ommitted, 0 is assumed.
- * Note that 0 is reasonable value for most protocols, except raw socket.
- *
- */
-static VALUE
-addrinfo_initialize(int argc, VALUE *argv, VALUE self)
-{
-    rb_addrinfo_t *rai;
-    VALUE sockaddr_arg, sockaddr_ary, pfamily, socktype, protocol;
-    int i_pfamily, i_socktype, i_protocol;
-    struct sockaddr *sockaddr_ptr;
-    size_t sockaddr_len;
-    VALUE canonname = Qnil, inspectname = Qnil;
-
-    if (check_addrinfo(self))
-        rb_raise(rb_eTypeError, "already initialized socket address");
-    DATA_PTR(self) = rai = alloc_addrinfo();
-
-    rb_scan_args(argc, argv, "13", &sockaddr_arg, &pfamily, &socktype, &protocol);
-
-    i_pfamily = NIL_P(pfamily) ? PF_UNSPEC : family_arg(pfamily);
-    i_socktype = NIL_P(socktype) ? 0 : socktype_arg(socktype);
-    i_protocol = NIL_P(protocol) ? 0 : NUM2INT(protocol);
-
-    sockaddr_ary = rb_check_array_type(sockaddr_arg);
-    if (!NIL_P(sockaddr_ary)) {
-        VALUE afamily = rb_ary_entry(sockaddr_ary, 0);
-        int af;
-        StringValue(afamily);
-        if (family_to_int(RSTRING_PTR(afamily), RSTRING_LEN(afamily), &af) == -1)
-	    rb_raise(rb_eSocket, "unknown address family: %s", StringValueCStr(afamily));
-        switch (af) {
-          case AF_INET: /* ["AF_INET", 46102, "localhost.localdomain", "127.0.0.1"] */
-#ifdef INET6
-          case AF_INET6: /* ["AF_INET6", 42304, "ip6-localhost", "::1"] */
-#endif
-          {
-            VALUE service = rb_ary_entry(sockaddr_ary, 1);
-            VALUE nodename = rb_ary_entry(sockaddr_ary, 2);
-            VALUE numericnode = rb_ary_entry(sockaddr_ary, 3);
-            int flags;
-
-            service = INT2NUM(NUM2INT(service));
-            if (!NIL_P(nodename))
-                StringValue(nodename);
-            StringValue(numericnode);
-            flags = AI_NUMERICHOST;
-#ifdef AI_NUMERICSERV
-            flags |= AI_NUMERICSERV;
-#endif
-
-            init_addrinfo_getaddrinfo(rai, numericnode, service,
-                    INT2NUM(i_pfamily ? i_pfamily : af), INT2NUM(i_socktype), INT2NUM(i_protocol),
-                    INT2NUM(flags),
-                    rb_str_equal(numericnode, nodename) ? Qnil : make_inspectname(nodename, service));
-            break;
-          }
-
-#ifdef HAVE_SYS_UN_H
-          case AF_UNIX: /* ["AF_UNIX", "/tmp/sock"] */
-          {
-            VALUE path = rb_ary_entry(sockaddr_ary, 1);
-            StringValue(path);
-            init_unix_addrinfo(rai, path);
-            break;
-          }
-#endif
-
-          default:
-            rb_raise(rb_eSocket, "unexpected address family");
-        }
-    }
-    else {
-        StringValue(sockaddr_arg);
-        sockaddr_ptr = (struct sockaddr *)RSTRING_PTR(sockaddr_arg);
-        sockaddr_len = RSTRING_LEN(sockaddr_arg);
-        init_addrinfo(rai, sockaddr_ptr, sockaddr_len,
-                      i_pfamily, i_socktype, i_protocol,
-                      canonname, inspectname);
-    }
-
-    return self;
-}
-
-static int
-get_afamily(struct sockaddr *addr, socklen_t len)
-{
-    if ((char*)&addr->sa_family + sizeof(addr->sa_family) - (char*)addr <= len)
-        return addr->sa_family;
-    else
-        return AF_UNSPEC;
-}
-
-static int
-ai_get_afamily(rb_addrinfo_t *rai)
-{
-    return get_afamily((struct sockaddr *)&rai->addr, rai->sockaddr_len);
-}
-
-/*
- * call-seq:
- *   addrinfo.inspect => string
- *
- * returns a string which shows addrinfo in human-readable form.
- *
- *   AddrInfo.tcp("localhost", 80).inspect #=> "#<AddrInfo: 127.0.0.1:80 TCP (localhost:80)>"
- *   AddrInfo.unix("/tmp/sock").inspect    #=> "#<AddrInfo: /tmp/sock SOCK_STREAM>"
- *
- */
-static VALUE
-addrinfo_inspect(VALUE self)
-{
-    rb_addrinfo_t *rai = get_addrinfo(self);
-    int internet_p;
-    VALUE ret;
-
-    ret = rb_sprintf("#<%s: ", rb_obj_classname(self));
-
-    if (rai->sockaddr_len == 0) {
-        rb_str_cat2(ret, "empty-sockaddr");
-    }
-    else if (rai->sockaddr_len < ((char*)&rai->addr.ss_family + sizeof(rai->addr.ss_family)) - (char*)&rai->addr)
-        rb_str_cat2(ret, "too-short-sockaddr");
-    else {
-        switch (rai->addr.ss_family) {
-          case AF_INET:
-          {
-            struct sockaddr_in *addr;
-            int port;
-            if (rai->sockaddr_len < sizeof(struct sockaddr_in)) {
-                rb_str_cat2(ret, "too-short-AF_INET-sockaddr");
-            }
-            else {
-                addr = (struct sockaddr_in *)&rai->addr;
-                rb_str_catf(ret, "%d.%d.%d.%d",
-                            ((unsigned char*)&addr->sin_addr)[0],
-                            ((unsigned char*)&addr->sin_addr)[1],
-                            ((unsigned char*)&addr->sin_addr)[2],
-                            ((unsigned char*)&addr->sin_addr)[3]);
-                port = ntohs(addr->sin_port);
-                if (port)
-                    rb_str_catf(ret, ":%d", port);
-                if (sizeof(struct sockaddr_in) < rai->sockaddr_len)
-                    rb_str_catf(ret, "(sockaddr %d bytes too long)", (int)(rai->sockaddr_len - sizeof(struct sockaddr_in)));
-            }
-            break;
-          }
-
-#ifdef INET6
-          case AF_INET6:
-          {
-            struct sockaddr_in6 *addr;
-            char hbuf[1024];
-            int port;
-            int error;
-            if (rai->sockaddr_len < sizeof(struct sockaddr_in6)) {
-                rb_str_cat2(ret, "too-short-AF_INET6-sockaddr");
-            }
-            else {
-                addr = (struct sockaddr_in6 *)&rai->addr;
-                /* use getnameinfo for scope_id.
-                 * RFC 4007: IPv6 Scoped Address Architecture
-                 * draft-ietf-ipv6-scope-api-00.txt: Scoped Address Extensions to the IPv6 Basic Socket API
-                 */
-                error = getnameinfo((struct sockaddr *)&rai->addr, rai->sockaddr_len,
-                                    hbuf, sizeof(hbuf), NULL, 0,
-                                    NI_NUMERICHOST|NI_NUMERICSERV);
-                if (error) {
-                    raise_socket_error("getnameinfo", error);
-                }
-                if (addr->sin6_port == 0) {
-                    rb_str_cat2(ret, hbuf);
-                }
-                else {
-                    port = ntohs(addr->sin6_port);
-                    rb_str_catf(ret, "[%s]:%d", hbuf, port);
-                }
-                if (sizeof(struct sockaddr_in6) < rai->sockaddr_len)
-                    rb_str_catf(ret, "(sockaddr %d bytes too long)", (int)(rai->sockaddr_len - sizeof(struct sockaddr_in6)));
-            }
-            break;
-          }
-#endif
-
-#ifdef HAVE_SYS_UN_H
-          case AF_UNIX:
-          {
-            struct sockaddr_un *addr = (struct sockaddr_un *)&rai->addr;
-            char *p, *s, *t, *e;
-            s = addr->sun_path;
-            e = (char*)addr + rai->sockaddr_len;
-            if (e < s)
-                rb_str_cat2(ret, "too-short-AF_UNIX-sockaddr");
-            else if (s == e)
-                rb_str_cat2(ret, "empty-path-AF_UNIX-sockaddr");
-            else {
-                int printable_only = 1;
-                p = s;
-                while (p < e && *p != '\0') {
-                    printable_only = printable_only && ISPRINT(*p) && !ISSPACE(*p);
-                    p++;
-                }
-                t = p;
-                while (p < e && *p == '\0')
-                    p++;
-                if (printable_only && /* only printable, no space */
-                    t < e && /* NUL terminated */
-                    p == e) { /* no data after NUL */
-		    if (s == t)
-			rb_str_cat2(ret, "empty-path-AF_UNIX-sockaddr");
-		    else if (s[0] == '/') /* absolute path */
-			rb_str_cat2(ret, s);
-		    else
-                        rb_str_catf(ret, "AF_UNIX %s", s);
-                }
-                else {
-                    rb_str_cat2(ret, "AF_UNIX");
-                    e = (char *)addr->sun_path + sizeof(addr->sun_path);
-                    while (s < e && *(e-1) == '\0')
-                        e--;
-                    while (s < e)
-                        rb_str_catf(ret, ":%02x", (unsigned char)*s++);
-                }
-                if (addr->sun_path + sizeof(addr->sun_path) < (char*)&rai->addr + rai->sockaddr_len)
-                    rb_str_catf(ret, "(sockaddr %d bytes too long)",
-                            (int)(rai->sockaddr_len - (addr->sun_path + sizeof(addr->sun_path) - (char*)&rai->addr)));
-            }
-            break;
-          }
-#endif
-
-          default:
-          {
-            ID id = intern_family(rai->addr.ss_family);
-            if (id == 0)
-                rb_str_catf(ret, "unknown address family %d", rai->addr.ss_family);
-            else
-                rb_str_catf(ret, "%s address format unknown", rb_id2name(id));
-            break;
-          }
-        }
-    }
-
-    if (rai->pfamily && ai_get_afamily(rai) != rai->pfamily) {
-        ID id = intern_protocol_family(rai->pfamily);
-        if (id)
-            rb_str_catf(ret, " %s", rb_id2name(id));
-        else
-            rb_str_catf(ret, " PF_\?\?\?(%d)", rai->pfamily);
-    }
-
-    internet_p = rai->pfamily == PF_INET;
-#ifdef INET6
-    internet_p = internet_p || rai->pfamily == PF_INET6;
-#endif
-    if (internet_p && rai->socktype == SOCK_STREAM &&
-        (rai->protocol == 0 || rai->protocol == IPPROTO_TCP)) {
-        rb_str_cat2(ret, " TCP");
-    }
-    else if (internet_p && rai->socktype == SOCK_DGRAM &&
-        (rai->protocol == 0 || rai->protocol == IPPROTO_UDP)) {
-        rb_str_cat2(ret, " UDP");
-    }
-    else {
-        if (rai->socktype) {
-            ID id = intern_socktype(rai->socktype);
-            if (id)
-                rb_str_catf(ret, " %s", rb_id2name(id));
-            else
-                rb_str_catf(ret, " SOCK_\?\?\?(%d)", rai->socktype);
-        }
-
-        if (rai->protocol) {
-            if (internet_p) {
-                ID id = intern_ipproto(rai->protocol);
-                if (id)
-                    rb_str_catf(ret, " %s", rb_id2name(id));
-                else
-                    goto unknown_protocol;
-            }
-            else {
-              unknown_protocol:
-                rb_str_catf(ret, " UNKNOWN_PROTOCOL(%d)", rai->protocol);
-            }
-        }
-    }
-
-    if (!NIL_P(rai->canonname)) {
-        VALUE name = rai->canonname;
-        rb_str_catf(ret, " %s", StringValueCStr(name));
-    }
-
-    if (!NIL_P(rai->inspectname)) {
-        VALUE name = rai->inspectname;
-        rb_str_catf(ret, " (%s)", StringValueCStr(name));
-    }
-
-    rb_str_buf_cat2(ret, ">");
-    return ret;
-}
-
-/*
- * call-seq:
- *   addrinfo.afamily => integer
- *
- * returns the address family as an integer.
- *
- *   AddrInfo.tcp("localhost", 80).afamily == Socket::AF_INET #=> true
- *
- */
-static VALUE
-addrinfo_afamily(VALUE self)
-{
-    rb_addrinfo_t *rai = get_addrinfo(self);
-    return INT2NUM(ai_get_afamily(rai));
-}
-
-/*
- * call-seq:
- *   addrinfo.pfamily => integer
- *
- * returns the protocol family as an integer.
- *
- *   AddrInfo.tcp("localhost", 80).pfamily == Socket::PF_INET #=> true
- *
- */
-static VALUE
-addrinfo_pfamily(VALUE self)
-{
-    rb_addrinfo_t *rai = get_addrinfo(self);
-    return INT2NUM(rai->pfamily);
-}
-
-/*
- * call-seq:
- *   addrinfo.socktype => integer
- *
- * returns the socket type as an integer.
- *
- *   AddrInfo.tcp("localhost", 80).socktype == Socket::SOCK_STREAM #=> true
- *
- */
-static VALUE
-addrinfo_socktype(VALUE self)
-{
-    rb_addrinfo_t *rai = get_addrinfo(self);
-    return INT2NUM(rai->socktype);
-}
-
-/*
- * call-seq:
- *   addrinfo.protocol => integer
- *
- * returns the socket type as an integer.
- *
- *   AddrInfo.tcp("localhost", 80).protocol == Socket::IPPROTO_TCP #=> true
- *
- */
-static VALUE
-addrinfo_protocol(VALUE self)
-{
-    rb_addrinfo_t *rai = get_addrinfo(self);
-    return INT2NUM(rai->protocol);
-}
-
-/*
- * call-seq:
- *   addrinfo.to_sockaddr => string
- *
- * returns the socket address as packed struct sockaddr string.
- *
- *   AddrInfo.tcp("localhost", 80).to_sockaddr                    
- *   #=> "\x02\x00\x00P\x7F\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00"
- *
- */
-static VALUE
-addrinfo_to_sockaddr(VALUE self)
-{
-    rb_addrinfo_t *rai = get_addrinfo(self);
-    VALUE ret;
-    ret = rb_str_new((char*)&rai->addr, rai->sockaddr_len);
-    OBJ_INFECT(ret, self);
-    return ret;
-}
-
-/*
- * call-seq:
- *   addrinfo.canonname => string or nil
- *
- * returns the canonical name as an string.
- *
- * nil is returned if no canonical name.
- *
- * The canonical name is set by AddrInfo.getaddrinfo when AI_CANONNAME is specified.
- *
- *   list = AddrInfo.getaddrinfo("www.ruby-lang.org", 80, :INET, :STREAM, nil, Socket::AI_CANONNAME)
- *   p list[0] #=> #<AddrInfo: 221.186.184.68:80 TCP carbon.ruby-lang.org (www.ruby-lang.org:80)>
- *   p list[0].canonname #=> "carbon.ruby-lang.org"
- *
- */
-static VALUE
-addrinfo_canonname(VALUE self)
-{
-    rb_addrinfo_t *rai = get_addrinfo(self);
-    return rai->canonname;
-}
-
-#ifdef AF_INET6
-# define IS_IP_FAMILY(af) ((af) == AF_INET || (af) == AF_INET6)
-#else
-# define IS_IP_FAMILY(af) ((af) == AF_INET)
-#endif
-
-/*
- * call-seq:
- *   addrinfo.ip? => true or false
- *
- * returns true if addrinfo is internet (IPv4/IPv6) address.
- * returns false otherwise.
- *
- *   AddrInfo.tcp("127.0.0.1", 80).ip? #=> true
- *   AddrInfo.tcp("::1", 80).ip?       #=> true
- *   AddrInfo.unix("/tmp/sock").ip?    #=> false
- *
- */
-static VALUE
-addrinfo_ip_p(VALUE self)
-{
-    rb_addrinfo_t *rai = get_addrinfo(self);
-    int family = ai_get_afamily(rai);
-    return IS_IP_FAMILY(family) ? Qtrue : Qfalse;
-}
-
-/*
- * call-seq:
- *   addrinfo.ipv4? => true or false
- *
- * returns true if addrinfo is IPv4 address.
- * returns false otherwise.
- *
- *   AddrInfo.tcp("127.0.0.1", 80).ipv4? #=> true
- *   AddrInfo.tcp("::1", 80).ipv4?       #=> false
- *   AddrInfo.unix("/tmp/sock").ipv4?    #=> false
- *
- */
-static VALUE
-addrinfo_ipv4_p(VALUE self)
-{
-    rb_addrinfo_t *rai = get_addrinfo(self);
-    return ai_get_afamily(rai) == AF_INET ? Qtrue : Qfalse;
-}
-
-/*
- * call-seq:
- *   addrinfo.ipv6? => true or false
- *
- * returns true if addrinfo is IPv6 address.
- * returns false otherwise.
- *
- *   AddrInfo.tcp("127.0.0.1", 80).ipv6? #=> false
- *   AddrInfo.tcp("::1", 80).ipv6?       #=> true
- *   AddrInfo.unix("/tmp/sock").ipv6?    #=> false
- *
- */
-static VALUE
-addrinfo_ipv6_p(VALUE self)
-{
-#ifdef AF_INET6
-    rb_addrinfo_t *rai = get_addrinfo(self);
-    return ai_get_afamily(rai) == AF_INET6 ? Qtrue : Qfalse;
-#else
-    return Qfalse;
-#endif
-}
-
-/*
- * call-seq:
- *   addrinfo.unix? => true or false
- *
- * returns true if addrinfo is UNIX address.
- * returns false otherwise.
- *
- *   AddrInfo.tcp("127.0.0.1", 80).unix? #=> false
- *   AddrInfo.tcp("::1", 80).unix?       #=> false
- *   AddrInfo.unix("/tmp/sock").unix?    #=> true
- *
- */
-static VALUE
-addrinfo_unix_p(VALUE self)
-{
-    rb_addrinfo_t *rai = get_addrinfo(self);
-#ifdef AF_UNIX
-    return ai_get_afamily(rai) == AF_UNIX ? Qtrue : Qfalse;
-#else
-    return Qfalse;
-#endif
-}
-
-/*
- * call-seq:
- *   addrinfo.getnameinfo        => [nodename, service]
- *   addrinfo.getnameinfo(flags) => [nodename, service]
- *
- * returns nodename and service as a pair of strings.
- * This converts struct sockaddr in addrinfo to textual representation.
- *
- * flags should be bitwise OR of Socket::NI_??? constants.
- *
- *   AddrInfo.tcp("127.0.0.1", 80).getnameinfo #=> ["localhost", "www"]
- *
- *   AddrInfo.tcp("127.0.0.1", 80).getnameinfo(Socket::NI_NUMERICSERV)
- *   #=> ["localhost", "80"]
- */
-static VALUE
-addrinfo_getnameinfo(int argc, VALUE *argv, VALUE self)
-{
-    rb_addrinfo_t *rai = get_addrinfo(self);
-    VALUE vflags;
-    char hbuf[1024], pbuf[1024];
-    int flags, error;
-
-    rb_scan_args(argc, argv, "01", &vflags);
-
-    flags = NIL_P(vflags) ? 0 : NUM2INT(vflags);
-
-    if (rai->socktype == SOCK_DGRAM)
-        flags |= NI_DGRAM;
-
-    error = getnameinfo((struct sockaddr *)&rai->addr, rai->sockaddr_len,
-                        hbuf, sizeof(hbuf), pbuf, sizeof(pbuf),
-                        flags);
-    if (error) {
-        raise_socket_error("getnameinfo", error);
-    }
-
-    return rb_assoc_new(rb_str_new2(hbuf), rb_str_new2(pbuf));
-}
-
-/*
- * call-seq:
- *   addrinfo.ip_unpack => [addr, port]
- *
- * Returns the IP address and port number as 2-element array.
- *
- *   AddrInfo.tcp("127.0.0.1", 80).ip_unpack    #=> ["127.0.0.1", 80]
- *   AddrInfo.tcp("::1", 80).ip_unpack          #=> ["::1", 80]
- */
-static VALUE
-addrinfo_ip_unpack(VALUE self)
-{
-    rb_addrinfo_t *rai = get_addrinfo(self);
-    int family = ai_get_afamily(rai);
-    VALUE vflags;
-    VALUE ret, portstr;
-
-    if (!IS_IP_FAMILY(family))
-	rb_raise(rb_eSocket, "need IPv4 or IPv6 address");
-
-    vflags = INT2NUM(NI_NUMERICHOST|NI_NUMERICSERV);
-    ret = addrinfo_getnameinfo(1, &vflags, self);
-    portstr = rb_ary_entry(ret, 1);
-    rb_ary_store(ret, 1, INT2NUM(atoi(StringValueCStr(portstr))));
-    return ret;
-}
-
-#ifdef HAVE_SYS_UN_H
-/*
- * call-seq:
- *   addrinfo.unix_path => path
- *
- * Returns the socket path as a string.
- *
- *   AddrInfo.unix("/tmp/sock").unix_path       #=> "/tmp/sock"
- */
-static VALUE
-addrinfo_unix_path(VALUE self)
-{
-    rb_addrinfo_t *rai = get_addrinfo(self);
-    int family = ai_get_afamily(rai);
-    struct sockaddr_un *addr;
-    char *s, *e;
-
-    if (family != AF_UNIX)
-	rb_raise(rb_eSocket, "need AF_UNIX address");
-
-    addr = (struct sockaddr_un *)&rai->addr;
-
-    s = addr->sun_path;
-    e = (char*)addr + rai->sockaddr_len;
-    if (e < s)
-        rb_raise(rb_eSocket, "too short AF_UNIX address");
-    if (addr->sun_path + sizeof(addr->sun_path) < e)
-        rb_raise(rb_eSocket, "too long AF_UNIX address");
-    while (s < e && *(e-1) == '\0')
-        e--;
-    return rb_str_new(s, e-s);
-}
-#endif
-
-/*
- * call-seq:
- *   AddrInfo.getaddrinfo(nodename, service, family, socktype, protocol, flags) => [addrinfo, ...]
- *   AddrInfo.getaddrinfo(nodename, service, family, socktype, protocol)        => [addrinfo, ...]
- *   AddrInfo.getaddrinfo(nodename, service, family, socktype)                  => [addrinfo, ...]
- *   AddrInfo.getaddrinfo(nodename, service, family)                            => [addrinfo, ...]
- *   AddrInfo.getaddrinfo(nodename, service)                                    => [addrinfo, ...]
- *
- * returns a list of addrinfo objects as an array.
- *
- * This method converts nodename (hostname) and service (port) to addrinfo.
- * Since the conversion is not unique, the result is a list of addrinfo objects.
- *
- * nodename or service can be nil if no conversion intended.
- *
- * family, socktype and protocol are hint for prefered protocol.
- * If the result will be used for a socket with SOCK_STREAM, 
- * SOCK_STREAM should be specified as socktype.
- * If so, AddrInfo.getaddrinfo returns addrinfo list appropriate for SOCK_STREAM.
- * If they are omitted or nil is given, the result is not restricted.
- * 
- * Similary, PF_INET6 as family restricts for IPv6.
- *
- * flags should be bitwise OR of Socket::AI_??? constants.
- *
- *   AddrInfo.getaddrinfo("www.kame.net", 80, nil, :STREAM)
- *   #=> [#<AddrInfo: 203.178.141.194:80 TCP (www.kame.net:80)>,
- *   #    #<AddrInfo: [2001:200:0:8002:203:47ff:fea5:3085]:80 TCP (www.kame.net:80)>]
- *
- */
-static VALUE
-addrinfo_s_getaddrinfo(int argc, VALUE *argv, VALUE self)
-{
-    VALUE node, service, family, socktype, protocol, flags;
-
-    rb_scan_args(argc, argv, "24", &node, &service, &family, &socktype, &protocol, &flags);
-    return addrinfo_list_new(node, service, family, socktype, protocol, flags);
-}
-
-
-/*
- * call-seq:
- *   AddrInfo.ip(host) => addrinfo
- *
- * returns an addrinfo object for IP address.
- *
- *   AddrInfo.ip("localhost") #=> #<AddrInfo: 127.0.0.1 (localhost)>
- */
-static VALUE
-addrinfo_s_ip(VALUE self, VALUE host)
-{
-    VALUE ret;
-    rb_addrinfo_t *rai;
-    ret = addrinfo_firstonly_new(host, Qnil,
-            INT2NUM(PF_UNSPEC), INT2FIX(0), INT2FIX(0), INT2FIX(0));
-    rai = get_addrinfo(ret);
-    rai->socktype = 0;
-    rai->protocol = 0;
-    return ret;
-}
-
-/*
- * call-seq:
- *   AddrInfo.tcp(host, port) => addrinfo
- *
- * returns an addrinfo object for TCP address.
- *
- *   AddrInfo.tcp("localhost", "smtp") #=> #<AddrInfo: 127.0.0.1:25 TCP (localhost:smtp)>
- */
-static VALUE
-addrinfo_s_tcp(VALUE self, VALUE host, VALUE port)
-{
-    return addrinfo_firstonly_new(host, port,
-            INT2NUM(PF_UNSPEC), INT2NUM(SOCK_STREAM), INT2NUM(IPPROTO_TCP), INT2FIX(0));
-}
-
-/*
- * call-seq:
- *   AddrInfo.udp(host, port) => addrinfo
- *
- * returns an addrinfo object for UDP address.
- *
- *   AddrInfo.udp("localhost", "daytime") #=> #<AddrInfo: 127.0.0.1:13 UDP (localhost:daytime)>
- */
-static VALUE
-addrinfo_s_udp(VALUE self, VALUE host, VALUE port)
-{
-    return addrinfo_firstonly_new(host, port,
-            INT2NUM(PF_UNSPEC), INT2NUM(SOCK_DGRAM), INT2NUM(IPPROTO_UDP), INT2FIX(0));
-}
-
-#ifdef HAVE_SYS_UN_H
-
-/*
- * call-seq:
- *   AddrInfo.udp(host, port) => addrinfo
- *
- * returns an addrinfo object for UNIX socket address.
- *
- *   AddrInfo.unix("/tmp/sock") #=> #<AddrInfo: /tmp/sock SOCK_STREAM>
- */
-static VALUE
-addrinfo_s_unix(VALUE self, VALUE path)
-{
-    VALUE addr;
-    rb_addrinfo_t *rai;
-
-    addr = addrinfo_s_allocate(rb_cAddrInfo);
-    DATA_PTR(addr) = rai = alloc_addrinfo();
-    init_unix_addrinfo(rai, path);
-    OBJ_INFECT(addr, path);
-    return addr;
-}
-
-#endif
-
-static VALUE
-sockaddr_string_value(volatile VALUE *v)
-{
-    VALUE val = *v;
-    if (TYPE(val) == RUBY_T_DATA && IS_ADDRINFO(val)) {
-        *v = addrinfo_to_sockaddr(val);
-    }
-    StringValue(*v);
-    return *v;
-}
-
-static char *
-sockaddr_string_value_ptr(volatile VALUE *v)
-{
-    sockaddr_string_value(v);
-    return RSTRING_PTR(*v);
-}
-
-
-static VALUE
-init_sock(VALUE sock, int fd)
-{
-    rb_io_t *fp;
-
-    MakeOpenFile(sock, fp);
-    fp->fd = fd;
-    fp->mode = FMODE_READWRITE|FMODE_DUPLEX;
-    rb_io_ascii8bit_binmode(sock);
-    if (do_not_reverse_lookup) {
-	fp->mode |= FMODE_NOREVLOOKUP;
-    }
-    rb_io_synchronized(fp);
-
-    return sock;
-}
-
-/*
- * call-seq:
- *   BasicSocket.for_fd(fd) => basicsocket
- *
- * Returns a socket object which contains the file descriptor, _fd_.
- *
- *   # If invoked by inetd, STDIN/STDOUT/STDERR is a socket.
- *   STDIN_SOCK = Socket.for_fd(STDIN.fileno)
- *   p STDIN_SOCK.remote_address
- *
- */
-static VALUE
-bsock_s_for_fd(VALUE klass, VALUE fd)
-{
-    rb_io_t *fptr;
-    VALUE sock = init_sock(rb_obj_alloc(klass), NUM2INT(fd));
-
-    GetOpenFile(sock, fptr);
-
-    return sock;
-}
-
-/*
- * call-seq:
- *   basicsocket.shutdown([how]) => 0
- *
- * Calls shutdown(2) system call.
- *
- * s.shutdown(Socket::SHUT_RD) disallows further read.
- *
- * s.shutdown(Socket::SHUT_WR) disallows further write.
- *
- * s.shutdown(Socket::SHUT_RDWR) disallows further read and write.
- *
- * _how_ can be symbol or string:
- * - :RD, :SHUT_RD, "RD" and "SHUT_RD" are accepted as Socket::SHUT_RD.
- * - :WR, :SHUT_WR, "WR" and "SHUT_WR" are accepted as Socket::SHUT_WR.
- * - :RDWR, :SHUT_RDWR, "RDWR" and "SHUT_RDWR" are accepted as Socket::SHUT_RDWR.
- *
- *   UNIXSocket.pair {|s1, s2|
- *     s1.puts "ping"
- *     s1.shutdown(:WR)
- *     p s2.read          #=> "ping\n"
- *     s2.puts "pong"
- *     s2.close
- *     p s1.read          #=> "pong\n"
- *   }
- *   
- */
-static VALUE
-bsock_shutdown(int argc, VALUE *argv, VALUE sock)
-{
-    VALUE howto;
-    int how;
-    rb_io_t *fptr;
-
-    if (rb_safe_level() >= 4 && !OBJ_TAINTED(sock)) {
-	rb_raise(rb_eSecurityError, "Insecure: can't shutdown socket");
-    }
-    rb_scan_args(argc, argv, "01", &howto);
-    if (howto == Qnil)
-	how = SHUT_RDWR;
-    else {
-	how = shutdown_how_arg(howto);
-        if (how != SHUT_WR && how != SHUT_RD && how != SHUT_RDWR) {
-	    rb_raise(rb_eArgError, "`how' should be either :SHUT_RD, :SHUT_WR, :SHUT_RDWR");
-	}
-    }
-    GetOpenFile(sock, fptr);
-    if (shutdown(fptr->fd, how) == -1)
-	rb_sys_fail(0);
-
-    return INT2FIX(0);
-}
-
-/*
- * call-seq:
- *   basicsocket.close_read => nil
- *
- * Disallows further read.
- *
- *   s1, s2 = UNIXSocket.pair
- *   s1.close_read
- *   s2.puts #=> Broken pipe (Errno::EPIPE)
- */
-static VALUE
-bsock_close_read(VALUE sock)
-{
-    rb_io_t *fptr;
-
-    if (rb_safe_level() >= 4 && !OBJ_TAINTED(sock)) {
-	rb_raise(rb_eSecurityError, "Insecure: can't close socket");
-    }
-    GetOpenFile(sock, fptr);
-    shutdown(fptr->fd, 0);
-    if (!(fptr->mode & FMODE_WRITABLE)) {
-	return rb_io_close(sock);
-    }
-    fptr->mode &= ~FMODE_READABLE;
-
-    return Qnil;
-}
-
-/*
- * call-seq:
- *   basicsocket.close_write => nil
- *
- * Disallows further write.
- *
- *   UNIXSocket.pair {|s1, s2|
- *     s1.print "ping"
- *     s1.close_write
- *     p s2.read        #=> "ping"
- *     s2.print "pong"
- *     s2.close
- *     p s1.read        #=> "pong"
- *   }
- */
-static VALUE
-bsock_close_write(VALUE sock)
-{
-    rb_io_t *fptr;
-
-    if (rb_safe_level() >= 4 && !OBJ_TAINTED(sock)) {
-	rb_raise(rb_eSecurityError, "Insecure: can't close socket");
-    }
-    GetOpenFile(sock, fptr);
-    if (!(fptr->mode & FMODE_READABLE)) {
-	return rb_io_close(sock);
-    }
-    shutdown(fptr->fd, 1);
-    fptr->mode &= ~FMODE_WRITABLE;
-
-    return Qnil;
-}
-
-/*
- * Document-method: setsockopt
- * call-seq: setsockopt(level, optname, optval)
- *
- * Sets a socket option. These are protocol and system specific, see your
- * local sytem documentation for details.
- *
- * === Parameters
- * * +level+ is an integer, usually one of the SOL_ constants such as
- *   Socket::SOL_SOCKET, or a protocol level.
- * * +optname+ is an integer, usually one of the SO_ constants, such
- *   as Socket::SO_REUSEADDR.
- * * +optval+ is the value of the option, it is passed to the underlying
- *   setsockopt() as a pointer to a certain number of bytes. How this is
- *   done depends on the type:
- *   - Fixnum: value is assigned to an int, and a pointer to the int is
- *     passed, with length of sizeof(int).
- *   - true or false: 1 or 0 (respectively) is assigned to an int, and the
- *     int is passed as for a Fixnum. Note that +false+ must be passed,
- *     not +nil+.
- *   - String: the string's data and length is passed to the socket.
- *
- * === Examples
- *
- * Some socket options are integers with boolean values, in this case
- * #setsockopt could be called like this:
- *   sock.setsockopt(Socket::SOL_SOCKET,Socket::SO_REUSEADDR, true)
- *
- * Some socket options are integers with numeric values, in this case
- * #setsockopt could be called like this:
- *   sock.setsockopt(Socket::IPPROTO_IP, Socket::IP_TTL, 255)
- *
- * Option values may be structs. Passing them can be complex as it involves
- * examining your system headers to determine the correct definition. An
- * example is an +ip_mreq+, which may be defined in your system headers as:
- *   struct ip_mreq {
- *     struct  in_addr imr_multiaddr;
- *     struct  in_addr imr_interface;
- *   };
- * 
- * In this case #setsockopt could be called like this:
- *   optval =  IPAddr.new("224.0.0.251") + Socket::INADDR_ANY
- *   sock.setsockopt(Socket::IPPROTO_IP, Socket::IP_ADD_MEMBERSHIP, optval)
- *
-*/
-static VALUE
-bsock_setsockopt(VALUE sock, VALUE lev, VALUE optname, VALUE val)
-{
-    int level, option;
-    rb_io_t *fptr;
-    int i;
-    char *v;
-    int vlen;
-
-    rb_secure(2);
-    level = level_arg(lev);
-    option = optname_arg(level, optname);
-
-    switch (TYPE(val)) {
-      case T_FIXNUM:
-	i = FIX2INT(val);
-	goto numval;
-      case T_FALSE:
-	i = 0;
-	goto numval;
-      case T_TRUE:
-	i = 1;
-      numval:
-	v = (char*)&i; vlen = sizeof(i);
-	break;
-      default:
-	StringValue(val);
-	v = RSTRING_PTR(val);
-	vlen = RSTRING_LEN(val);
-	break;
-    }
-
-#define rb_sys_fail_path(path) rb_sys_fail(NIL_P(path) ? 0 : RSTRING_PTR(path))
-
-    GetOpenFile(sock, fptr);
-    if (setsockopt(fptr->fd, level, option, v, vlen) < 0)
-	rb_sys_fail_path(fptr->pathv);
-
-    return INT2FIX(0);
-}
-
-/*
- * Document-method: getsockopt
- * call-seq: getsockopt(level, optname)
- *
- * Gets a socket option. These are protocol and system specific, see your
- * local sytem documentation for details. The option is returned as
- * a String with the data being the binary value of the socket option.
- *
- * === Parameters
- * * +level+ is an integer, usually one of the SOL_ constants such as
- *   Socket::SOL_SOCKET, or a protocol level.
- * * +optname+ is an integer, usually one of the SO_ constants, such
- *   as Socket::SO_REUSEADDR.
- *
- * === Examples
- *
- * Some socket options are integers with boolean values, in this case
- * #getsockopt could be called like this:
- *   optval = sock.getsockopt(Socket::SOL_SOCKET,Socket::SO_REUSEADDR)
- *   optval = optval.unpack "i"
- *   reuseaddr = optval[0] == 0 ? false : true
- *
- * Some socket options are integers with numeric values, in this case
- * #getsockopt could be called like this:
- *   optval = sock.getsockopt(Socket::IPPROTO_IP, Socket::IP_TTL)
- *   ipttl = optval.unpack("i")[0]
- *
- * Option values may be structs. Decoding them can be complex as it involves
- * examining your system headers to determine the correct definition. An
- * example is a +struct linger+, which may be defined in your system headers
- * as:
- *   struct linger {
- *     int l_onoff;
- *     int l_linger;
- *   };
- * 
- * In this case #getsockopt could be called like this:
- *   optval =  sock.getsockopt(Socket::SOL_SOCKET, Socket::SO_LINGER)
- *   onoff, linger = optval.unpack "ii"
-*/
-static VALUE
-bsock_getsockopt(VALUE sock, VALUE lev, VALUE optname)
-{
-#if !defined(__BEOS__)
-    int level, option;
-    socklen_t len;
-    char *buf;
-    rb_io_t *fptr;
-
-    level = level_arg(lev);
-    option = optname_arg(level, optname);
-    len = 256;
-    buf = ALLOCA_N(char,len);
-
-    GetOpenFile(sock, fptr);
-    if (getsockopt(fptr->fd, level, option, buf, &len) < 0)
-	rb_sys_fail_path(fptr->pathv);
-
-    return rb_str_new(buf, len);
-#else
-    rb_notimplement();
-#endif
-}
-
-/*
- * call-seq:
- *   basicsocket.getsockname => sockaddr
- *
- * Returns the local address of the socket as a sockaddr string.
- *
- *   TCPServer.open("127.0.0.1", 15120) {|serv|
- *     p serv.getsockname #=> "\x02\x00;\x10\x7F\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00"
- *   }
- */
-static VALUE
-bsock_getsockname(VALUE sock)
-{
-    char buf[1024];
-    socklen_t len = sizeof buf;
-    rb_io_t *fptr;
-
-    GetOpenFile(sock, fptr);
-    if (getsockname(fptr->fd, (struct sockaddr*)buf, &len) < 0)
-	rb_sys_fail("getsockname(2)");
-    return rb_str_new(buf, len);
-}
-
-/*
- * call-seq:
- *   basicsocket.getpeername => sockaddr
- *
- * Returns the remote address of the socket as a sockaddr string.
- *
- *   TCPServer.open("127.0.0.1", 1440) {|serv|
- *     c = TCPSocket.new("127.0.0.1", 1440)
- *     s = serv.accept
- *     p s.getpeername #=> "\x02\x00\x82u\x7F\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00"
- *   }
- *
- */
-static VALUE
-bsock_getpeername(VALUE sock)
-{
-    char buf[1024];
-    socklen_t len = sizeof buf;
-    rb_io_t *fptr;
-
-    GetOpenFile(sock, fptr);
-    if (getpeername(fptr->fd, (struct sockaddr*)buf, &len) < 0)
-	rb_sys_fail("getpeername(2)");
-    return rb_str_new(buf, len);
-}
-
-static VALUE addrinfo_new(struct sockaddr *, socklen_t, int, int, int, VALUE, VALUE);
-
-static VALUE
-fd_socket_addrinfo(int fd, struct sockaddr *addr, socklen_t len)
-{
-    int family;
-    int socktype;
-    int ret;
-    socklen_t optlen = sizeof(socktype);
-
-    /* assumes protocol family and address family are identical */
-    family = get_afamily(addr, len);
-
-    ret = getsockopt(fd, SOL_SOCKET, SO_TYPE, (void*)&socktype, &optlen);
-    if (ret == -1) {
-	rb_sys_fail("getsockopt(SO_TYPE)");
-    }
-
-    return addrinfo_new(addr, len, family, socktype, 0, Qnil, Qnil);
-}
-
-static VALUE
-io_socket_addrinfo(VALUE io, struct sockaddr *addr, socklen_t len)
-{
-    rb_io_t *fptr;
-
-    switch (TYPE(io)) {
-      case T_FIXNUM:
-        return fd_socket_addrinfo(FIX2INT(io), addr, len);
-
-      case T_BIGNUM:
-        return fd_socket_addrinfo(NUM2INT(io), addr, len);
-
-      case T_FILE:
-        GetOpenFile(io, fptr);
-        return fd_socket_addrinfo(fptr->fd, addr, len);
-
-      default:
-	rb_raise(rb_eTypeError, "neither IO nor file descriptor");
-    }
-}
-
-/*
- * call-seq:
- *   bsock.local_address => addrinfo
- *
- * Returns an AddrInfo object for local address obtained by getsockname.
- *
- * Note that addrinfo.protocol is filled by 0.
- *
- *   TCPServer.open("127.0.0.1", 1512) {|serv|
- *     p serv.local_address #=> #<AddrInfo: 127.0.0.1:1512 TCP>
- *   }
- *
- */
-static VALUE
-bsock_local_address(VALUE sock)
-{
-    char buf[1024];
-    socklen_t len = sizeof buf;
-    rb_io_t *fptr;
-
-    GetOpenFile(sock, fptr);
-    if (getsockname(fptr->fd, (struct sockaddr*)buf, &len) < 0)
-	rb_sys_fail("getsockname(2)");
-    return fd_socket_addrinfo(fptr->fd, (struct sockaddr *)buf, len);
-}
-
-/*
- * call-seq:
- *   bsock.remote_address => addrinfo
- *
- * Returns an AddrInfo object for remote address obtained by getpeername.
- *
- * Note that addrinfo.protocol is filled by 0.
- *
- *   TCPServer.open("127.0.0.1", 1728) {|serv|
- *     c = TCPSocket.new("127.0.0.1", 1728)
- *     s = serv.accept
- *     p s.remote_address #=> #<AddrInfo: 127.0.0.1:36504 TCP>
- *   }
- *
- */
-static VALUE
-bsock_remote_address(VALUE sock)
-{
-    char buf[1024];
-    socklen_t len = sizeof buf;
-    rb_io_t *fptr;
-
-    GetOpenFile(sock, fptr);
-    if (getpeername(fptr->fd, (struct sockaddr*)buf, &len) < 0)
-	rb_sys_fail("getpeername(2)");
-    return fd_socket_addrinfo(fptr->fd, (struct sockaddr *)buf, len);
-}
-
-struct send_arg {
-    int fd, flags;
-    VALUE mesg;
-    struct sockaddr *to;
-    socklen_t tolen;
-};
-
-static VALUE
-sendto_blocking(void *data)
-{
-    struct send_arg *arg = data;
-    VALUE mesg = arg->mesg;
-    return (VALUE)sendto(arg->fd, RSTRING_PTR(mesg), RSTRING_LEN(mesg),
-			 arg->flags, arg->to, arg->tolen);
-}
-
-static VALUE
-send_blocking(void *data)
-{
-    struct send_arg *arg = data;
-    VALUE mesg = arg->mesg;
-    return (VALUE)send(arg->fd, RSTRING_PTR(mesg), RSTRING_LEN(mesg),
-		       arg->flags);
-}
-
-#define SockAddrStringValue(v) sockaddr_string_value(&(v))
-#define SockAddrStringValuePtr(v) sockaddr_string_value_ptr(&(v))
-static VALUE sockaddr_string_value(volatile VALUE *);
-static char *sockaddr_string_value_ptr(volatile VALUE *);
-
-/*
- * call-seq:
- *   basicsocket.send(mesg, flags [, sockaddr_to]) => numbytes_sent
- *
- * send _mesg_ via _basicsocket_.
- *
- * _mesg_ should be a string.
- *
- * _flags_ should be a bitwise OR of Socket::MSG_* constants.
- *
- * _sockaddr_to_ should be a packed sockaddr string or an addrinfo.
- *
- *   TCPSocket.open("localhost", 80) {|s|
- *     s.send "GET / HTTP/1.0\r\n\r\n", 0
- *     p s.read
- *   }
- */
-static VALUE
-bsock_send(int argc, VALUE *argv, VALUE sock)
-{
-    struct send_arg arg;
-    VALUE flags, to;
-    rb_io_t *fptr;
-    int n;
-    rb_blocking_function_t *func;
-
-    rb_secure(4);
-    rb_scan_args(argc, argv, "21", &arg.mesg, &flags, &to);
-
-    StringValue(arg.mesg);
-    if (!NIL_P(to)) {
-	SockAddrStringValue(to);
-	to = rb_str_new4(to);
-	arg.to = (struct sockaddr *)RSTRING_PTR(to);
-	arg.tolen = RSTRING_LEN(to);
-	func = sendto_blocking;
-    }
-    else {
-	func = send_blocking;
-    }
-    GetOpenFile(sock, fptr);
-    arg.fd = fptr->fd;
-    arg.flags = NUM2INT(flags);
-    while (rb_thread_fd_writable(arg.fd),
-	   (n = (int)BLOCKING_REGION(func, &arg)) < 0) {
-	if (rb_io_wait_writable(arg.fd)) {
-	    continue;
-	}
-	rb_sys_fail("send(2)");
-    }
-    return INT2FIX(n);
-}
-
-/*
- * call-seq:
- *   basicsocket.do_not_reverse_lookup => true or false
- *
- * Gets the do_not_reverse_lookup flag of _basicsocket_.
- *
- *   TCPSocket.open("www.ruby-lang.org", 80) {|sock|
- *     p sock.do_not_reverse_lookup      #=> false
- *     p sock.peeraddr                   #=> ["AF_INET", 80, "carbon.ruby-lang.org", "221.186.184.68"]
- *     sock.do_not_reverse_lookup = true
- *     p sock.peeraddr                   #=> ["AF_INET", 80, "221.186.184.68", "221.186.184.68"]
- *   }
- */
-static VALUE
-bsock_do_not_reverse_lookup(VALUE sock)
-{
-    rb_io_t *fptr;
-
-    GetOpenFile(sock, fptr);
-    return (fptr->mode & FMODE_NOREVLOOKUP) ? Qtrue : Qfalse;
-}
-
-/*
- * call-seq:
- *   basicsocket.do_not_reverse_lookup = bool
- *
- * Sets the do_not_reverse_lookup flag of _basicsocket_.
- *
- *   BasicSocket.do_not_reverse_lookup = false
- *   p TCPSocket.new("127.0.0.1", 80).do_not_reverse_lookup #=> false
- *   BasicSocket.do_not_reverse_lookup = true
- *   p TCPSocket.new("127.0.0.1", 80).do_not_reverse_lookup #=> true
- *
- */
-static VALUE
-bsock_do_not_reverse_lookup_set(VALUE sock, VALUE state)
-{
-    rb_io_t *fptr;
-
-    rb_secure(4);
-    GetOpenFile(sock, fptr);
-    if (RTEST(state)) {
-	fptr->mode |= FMODE_NOREVLOOKUP;
-    }
-    else {
-	fptr->mode &= ~FMODE_NOREVLOOKUP;
-    }
-    return sock;
-}
-
-static VALUE ipaddr(struct sockaddr*, int);
-#ifdef HAVE_SYS_UN_H
-static VALUE unixaddr(struct sockaddr_un*, socklen_t);
-#endif
-
-enum sock_recv_type {
-    RECV_RECV,			/* BasicSocket#recv(no from) */
-    RECV_IP,			/* IPSocket#recvfrom */
-    RECV_UNIX,			/* UNIXSocket#recvfrom */
-    RECV_SOCKET			/* Socket#recvfrom */
-};
-
-struct recvfrom_arg {
-    int fd, flags;
-    VALUE str;
-    socklen_t alen;
-    char buf[1024];
-};
-
-static VALUE
-recvfrom_blocking(void *data)
-{
-    struct recvfrom_arg *arg = data;
-    return (VALUE)recvfrom(arg->fd, RSTRING_PTR(arg->str), RSTRING_LEN(arg->str),
-			   arg->flags, (struct sockaddr*)arg->buf, &arg->alen);
-}
-
-static VALUE
-s_recvfrom(VALUE sock, int argc, VALUE *argv, enum sock_recv_type from)
-{
-    rb_io_t *fptr;
-    VALUE str, klass;
-    struct recvfrom_arg arg;
-    VALUE len, flg;
-    long buflen;
-    long slen;
-
-    rb_scan_args(argc, argv, "11", &len, &flg);
-
-    if (flg == Qnil) arg.flags = 0;
-    else             arg.flags = NUM2INT(flg);
-    buflen = NUM2INT(len);
-
-    GetOpenFile(sock, fptr);
-    if (rb_io_read_pending(fptr)) {
-	rb_raise(rb_eIOError, "recv for buffered IO");
-    }
-    arg.fd = fptr->fd;
-    arg.alen = sizeof(arg.buf);
-
-    arg.str = str = rb_tainted_str_new(0, buflen);
-    klass = RBASIC(str)->klass;
-    RBASIC(str)->klass = 0;
-
-    while (rb_io_check_closed(fptr),
-	   rb_thread_wait_fd(arg.fd),
-	   (slen = BLOCKING_REGION(recvfrom_blocking, &arg)) < 0) {
-	if (RBASIC(str)->klass || RSTRING_LEN(str) != buflen) {
-	    rb_raise(rb_eRuntimeError, "buffer string modified");
-	}
-    }
-
-    RBASIC(str)->klass = klass;
-    if (slen < RSTRING_LEN(str)) {
-	rb_str_set_len(str, slen);
-    }
-    rb_obj_taint(str);
-    switch (from) {
-      case RECV_RECV:
-	return str;
-      case RECV_IP:
-#if 0
-	if (arg.alen != sizeof(struct sockaddr_in)) {
-	    rb_raise(rb_eTypeError, "sockaddr size differs - should not happen");
-	}
-#endif
-	if (arg.alen && arg.alen != sizeof(arg.buf)) /* OSX doesn't return a from result for connection-oriented sockets */
-	    return rb_assoc_new(str, ipaddr((struct sockaddr*)arg.buf, fptr->mode & FMODE_NOREVLOOKUP));
-	else
-	    return rb_assoc_new(str, Qnil);
-
-#ifdef HAVE_SYS_UN_H
-      case RECV_UNIX:
-        return rb_assoc_new(str, unixaddr((struct sockaddr_un*)arg.buf, arg.alen));
-#endif
-      case RECV_SOCKET:
-	return rb_assoc_new(str, io_socket_addrinfo(sock, (struct sockaddr*)arg.buf, arg.alen));
-      default:
-	rb_bug("s_recvfrom called with bad value");
-    }
-}
-
-static VALUE
-s_recvfrom_nonblock(VALUE sock, int argc, VALUE *argv, enum sock_recv_type from)
-{
-    rb_io_t *fptr;
-    VALUE str;
-    char buf[1024];
-    socklen_t alen = sizeof buf;
-    VALUE len, flg;
-    long buflen;
-    long slen;
-    int fd, flags;
-    VALUE addr = Qnil;
-
-    rb_scan_args(argc, argv, "11", &len, &flg);
-
-    if (flg == Qnil) flags = 0;
-    else             flags = NUM2INT(flg);
-    buflen = NUM2INT(len);
-
-#ifdef MSG_DONTWAIT
-    /* MSG_DONTWAIT avoids the race condition between fcntl and recvfrom.
-       It is not portable, though. */
-    flags |= MSG_DONTWAIT;
-#endif
-
-    GetOpenFile(sock, fptr);
-    if (rb_io_read_pending(fptr)) {
-	rb_raise(rb_eIOError, "recvfrom for buffered IO");
-    }
-    fd = fptr->fd;
-
-    str = rb_tainted_str_new(0, buflen);
-
-    rb_io_check_closed(fptr);
-    rb_io_set_nonblock(fptr);
-    slen = recvfrom(fd, RSTRING_PTR(str), buflen, flags, (struct sockaddr*)buf, &alen);
-
-    if (slen < 0) {
-	rb_sys_fail("recvfrom(2)");
-    }
-    if (slen < RSTRING_LEN(str)) {
-	rb_str_set_len(str, slen);
-    }
-    rb_obj_taint(str);
-    switch (from) {
-      case RECV_RECV:
-        return str;
-
-      case RECV_IP:
-        if (alen && alen != sizeof(buf)) /* connection-oriented socket may not return a from result */
-            addr = ipaddr((struct sockaddr*)buf, fptr->mode & FMODE_NOREVLOOKUP);
-        break;
-
-      case RECV_SOCKET:
-        addr = io_socket_addrinfo(sock, (struct sockaddr*)buf, alen);
-        break;
-
-      default:
-        rb_bug("s_recvfrom_nonblock called with bad value");
-    }
-    return rb_assoc_new(str, addr);
-}
-
-/*
- * call-seq:
- *   basicsocket.recv(maxlen) => mesg
- *   basicsocket.recv(maxlen, flags) => mesg
- *
- * Receives a message.
- *
- * _maxlen_ is the maximum number of bytes to receive.
- *
- * _flags_ should be a bitwise OR of Socket::MSG_* constants.
- *
- *   UNIXSocket.pair {|s1, s2|
- *     s1.puts "Hello World"
- *     p s2.recv(4)                     #=> "Hell"
- *     p s2.recv(4, Socket::MSG_PEEK)   #=> "o Wo"
- *     p s2.recv(4)                     #=> "o Wo"
- *     p s2.recv(10)                    #=> "rld\n"
- *   }
- */
-static VALUE
-bsock_recv(int argc, VALUE *argv, VALUE sock)
-{
-    return s_recvfrom(sock, argc, argv, RECV_RECV);
-}
-
-/*
- * call-seq:
- * 	basicsocket.recv_nonblock(maxlen) => mesg
- * 	basicsocket.recv_nonblock(maxlen, flags) => mesg
- * 
- * Receives up to _maxlen_ bytes from +socket+ using recvfrom(2) after
- * O_NONBLOCK is set for the underlying file descriptor.
- * _flags_ is zero or more of the +MSG_+ options.
- * The result, _mesg_, is the data received.
- *
- * When recvfrom(2) returns 0, Socket#recv_nonblock returns
- * an empty string as data.
- * The meaning depends on the socket: EOF on TCP, empty packet on UDP, etc.
- * 
- * === Parameters
- * * +maxlen+ - the number of bytes to receive from the socket
- * * +flags+ - zero or more of the +MSG_+ options 
- * 
- * === Example
- * 	serv = TCPServer.new("127.0.0.1", 0)
- * 	af, port, host, addr = serv.addr
- * 	c = TCPSocket.new(addr, port)
- * 	s = serv.accept
- * 	c.send "aaa", 0
- * 	IO.select([s]) # emulate blocking recv.
- * 	p s.recv_nonblock(10) #=> "aaa"
- *
- * Refer to Socket#recvfrom for the exceptions that may be thrown if the call
- * to _recv_nonblock_ fails. 
- *
- * BasicSocket#recv_nonblock may raise any error corresponding to recvfrom(2) failure,
- * including Errno::EWOULDBLOCK.
- *
- * === See
- * * Socket#recvfrom
- */
-
-static VALUE
-bsock_recv_nonblock(int argc, VALUE *argv, VALUE sock)
-{
-    return s_recvfrom_nonblock(sock, argc, argv, RECV_RECV);
-}
-
-/*
- * call-seq:
- *   BasicSocket.do_not_reverse_lookup => true or false
- *
- * Gets the global do_not_reverse_lookup flag.
- *
- *   BasicSocket.do_not_reverse_lookup  #=> false
- */
-static VALUE
-bsock_do_not_rev_lookup(void)
-{
-    return do_not_reverse_lookup?Qtrue:Qfalse;
-}
-
-/*
- * call-seq:
- *   BasicSocket.do_not_reverse_lookup = bool
- *
- * Sets the global do_not_reverse_lookup flag.
- *
- * The flag is used for initial value of do_not_reverse_lookup for each socket.
- *
- *   s1 = TCPSocket.new("localhost", 80)
- *   p s1.do_not_reverse_lookup                 #=> true
- *   BasicSocket.do_not_reverse_lookup = false
- *   s2 = TCPSocket.new("localhost", 80)
- *   p s2.do_not_reverse_lookup                 #=> false
- *   p s1.do_not_reverse_lookup                 #=> true
- *
- */
-static VALUE
-bsock_do_not_rev_lookup_set(VALUE self, VALUE val)
-{
-    rb_secure(4);
-    do_not_reverse_lookup = RTEST(val);
-    return val;
-}
-
-static void
-raise_socket_error(const char *reason, int error)
-{
-#ifdef EAI_SYSTEM
-    if (error == EAI_SYSTEM) rb_sys_fail(reason);
-#endif
-    rb_raise(rb_eSocket, "%s: %s", reason, gai_strerror(error));
-}
-
-static void
-make_ipaddr0(struct sockaddr *addr, char *buf, size_t len)
-{
-    int error;
-
-    error = rb_getnameinfo(addr, SA_LEN(addr), buf, len, NULL, 0, NI_NUMERICHOST);
-    if (error) {
-	raise_socket_error("getnameinfo", error);
-    }
-}
-
-static VALUE
-make_ipaddr(struct sockaddr *addr)
-{
-    char buf[1024];
-
-    make_ipaddr0(addr, buf, sizeof(buf));
-    return rb_str_new2(buf);
-}
-
-static void
-make_inetaddr(long host, char *buf, size_t len)
-{
-    struct sockaddr_in sin;
-
-    MEMZERO(&sin, struct sockaddr_in, 1);
-    sin.sin_family = AF_INET;
-    SET_SIN_LEN(&sin, sizeof(sin));
-    sin.sin_addr.s_addr = host;
-    make_ipaddr0((struct sockaddr*)&sin, buf, len);
-}
-
-static int
-str_isnumber(const char *p)
-{
-    char *ep;
-
-    if (!p || *p == '\0')
-       return 0;
-    ep = NULL;
-    (void)STRTOUL(p, &ep, 10);
-    if (ep && *ep == '\0')
-       return 1;
-    else
-       return 0;
-}
-
-static char*
-host_str(VALUE host, char *hbuf, size_t len, int *flags_ptr)
-{
-    if (NIL_P(host)) {
-	return NULL;
-    }
-    else if (rb_obj_is_kind_of(host, rb_cInteger)) {
-	unsigned long i = NUM2ULONG(host);
-
-	make_inetaddr(htonl(i), hbuf, len);
-        if (flags_ptr) *flags_ptr |= AI_NUMERICHOST;
-	return hbuf;
-    }
-    else {
-	char *name;
-
-	SafeStringValue(host);
-	name = RSTRING_PTR(host);
-	if (!name || *name == 0 || (name[0] == '<' && strcmp(name, "<any>") == 0)) {
-	    make_inetaddr(INADDR_ANY, hbuf, len);
-            if (flags_ptr) *flags_ptr |= AI_NUMERICHOST;
-	}
-	else if (name[0] == '<' && strcmp(name, "<broadcast>") == 0) {
-	    make_inetaddr(INADDR_BROADCAST, hbuf, len);
-            if (flags_ptr) *flags_ptr |= AI_NUMERICHOST;
-	}
-	else if (strlen(name) >= len) {
-	    rb_raise(rb_eArgError, "hostname too long (%"PRIuSIZE")",
-                strlen(name));
-	}
-	else {
-	    strcpy(hbuf, name);
-	}
-	return hbuf;
-    }
-}
-
-static char*
-port_str(VALUE port, char *pbuf, size_t len, int *flags_ptr)
-{
-    if (NIL_P(port)) {
-	return 0;
-    }
-    else if (FIXNUM_P(port)) {
-	snprintf(pbuf, len, "%ld", FIX2LONG(port));
-#ifdef AI_NUMERICSERV
-        if (flags_ptr) *flags_ptr |= AI_NUMERICSERV;
-#endif
-	return pbuf;
-    }
-    else {
-	char *serv;
-
-	SafeStringValue(port);
-	serv = RSTRING_PTR(port);
-	if (strlen(serv) >= len) {
-	    rb_raise(rb_eArgError, "service name too long (%"PRIuSIZE")",
-                strlen(serv));
-	}
-	strcpy(pbuf, serv);
-	return pbuf;
-    }
-}
-
-#ifndef NI_MAXHOST
-# define NI_MAXHOST 1025
-#endif
-#ifndef NI_MAXSERV
-# define NI_MAXSERV 32
-#endif
-
-static struct addrinfo*
-sock_getaddrinfo(VALUE host, VALUE port, struct addrinfo *hints, int socktype_hack)
-{
-    struct addrinfo* res = NULL;
-    char *hostp, *portp;
-    int error;
-    char hbuf[NI_MAXHOST], pbuf[NI_MAXSERV];
-    int additional_flags = 0;
-
-    hostp = host_str(host, hbuf, sizeof(hbuf), &additional_flags);
-    portp = port_str(port, pbuf, sizeof(pbuf), &additional_flags);
-
-    if (socktype_hack && hints->ai_socktype == 0 && str_isnumber(portp)) {
-       hints->ai_socktype = SOCK_DGRAM;
-    }
-    hints->ai_flags |= additional_flags;
-
-    error = rb_getaddrinfo(hostp, portp, hints, &res);
-    if (error) {
-	if (hostp && hostp[strlen(hostp)-1] == '\n') {
-	    rb_raise(rb_eSocket, "newline at the end of hostname");
-	}
-	raise_socket_error("getaddrinfo", error);
-    }
-
-#if defined(__APPLE__) && defined(__MACH__)
-    {
-	struct addrinfo *r;
-	r = res;
-	while (r) {
-	    if (! r->ai_socktype) r->ai_socktype = hints->ai_socktype;
-	    if (! r->ai_protocol) {
-		if (r->ai_socktype == SOCK_DGRAM) {
-		    r->ai_protocol = IPPROTO_UDP;
-		}
-		else if (r->ai_socktype == SOCK_STREAM) {
-		    r->ai_protocol = IPPROTO_TCP;
-		}
-	    }
-	    r = r->ai_next;
-	}
-    }
-#endif
-    return res;
-}
-
-static struct addrinfo*
-sock_addrinfo(VALUE host, VALUE port, int socktype, int flags)
-{
-    struct addrinfo hints;
-
-    MEMZERO(&hints, struct addrinfo, 1);
-    hints.ai_family = AF_UNSPEC;
-    hints.ai_socktype = socktype;
-    hints.ai_flags = flags;
-    return sock_getaddrinfo(host, port, &hints, 1);
-}
-
-static VALUE
-ipaddr(struct sockaddr *sockaddr, int norevlookup)
-{
-    VALUE family, port, addr1, addr2;
-    VALUE ary;
-    int error;
-    char hbuf[1024], pbuf[1024];
-    ID id;
-
-    id = intern_family(sockaddr->sa_family);
-    if (id) {
-        family = rb_str_dup(rb_id2str(id));
-    }
-    else {
-        sprintf(pbuf, "unknown:%d", sockaddr->sa_family);
-	family = rb_str_new2(pbuf);
-    }
-
-    addr1 = Qnil;
-    if (!norevlookup) {
-	error = rb_getnameinfo(sockaddr, SA_LEN(sockaddr), hbuf, sizeof(hbuf),
-			       NULL, 0, 0);
-	if (! error) {
-	    addr1 = rb_str_new2(hbuf);
-	}
-    }
-    error = rb_getnameinfo(sockaddr, SA_LEN(sockaddr), hbuf, sizeof(hbuf),
-			   pbuf, sizeof(pbuf), NI_NUMERICHOST | NI_NUMERICSERV);
-    if (error) {
-	raise_socket_error("getnameinfo", error);
-    }
-    addr2 = rb_str_new2(hbuf);
-    if (addr1 == Qnil) {
-	addr1 = addr2;
-    }
-    port = INT2FIX(atoi(pbuf));
-    ary = rb_ary_new3(4, family, port, addr1, addr2);
-
-    return ary;
-}
-
-static int
-ruby_socket(int domain, int type, int proto)
-{
-    int fd;
-
-    fd = socket(domain, type, proto);
-    if (fd < 0) {
-	if (errno == EMFILE || errno == ENFILE) {
-	    rb_gc();
-	    fd = socket(domain, type, proto);
-	}
-    }
-    return fd;
-}
-
-static int
-wait_connectable0(int fd, rb_fdset_t *fds_w, rb_fdset_t *fds_e)
-{
-    int sockerr;
-    socklen_t sockerrlen;
-
-    for (;;) {
-	rb_fd_zero(fds_w);
-	rb_fd_zero(fds_e);
-
-	rb_fd_set(fd, fds_w);
-	rb_fd_set(fd, fds_e);
-
-	rb_thread_select(fd+1, 0, rb_fd_ptr(fds_w), rb_fd_ptr(fds_e), 0);
-
-	if (rb_fd_isset(fd, fds_w)) {
-	    return 0;
-	}
-	else if (rb_fd_isset(fd, fds_e)) {
-	    sockerrlen = sizeof(sockerr);
-	    if (getsockopt(fd, SOL_SOCKET, SO_ERROR, (void *)&sockerr,
-			   &sockerrlen) == 0) {
-		if (sockerr == 0)
-		    continue;	/* workaround for winsock */
-		errno = sockerr;
-	    }
-	    return -1;
-	}
-    }
-
-    return 0;
-}
-
-struct wait_connectable_arg {
-    int fd;
-    rb_fdset_t fds_w;
-    rb_fdset_t fds_e;
-};
-
-#ifdef HAVE_RB_FD_INIT
-static VALUE
-try_wait_connectable(VALUE arg)
-{
-    struct wait_connectable_arg *p = (struct wait_connectable_arg *)arg;
-    return (VALUE)wait_connectable0(p->fd, &p->fds_w, &p->fds_e);
-}
-
-static VALUE
-wait_connectable_ensure(VALUE arg)
-{
-    struct wait_connectable_arg *p = (struct wait_connectable_arg *)arg;
-    rb_fd_term(&p->fds_w);
-    rb_fd_term(&p->fds_e);
-    return Qnil;
-}
-#endif
-
-static int
-wait_connectable(int fd)
-{
-    struct wait_connectable_arg arg;
-
-    rb_fd_init(&arg.fds_w);
-    rb_fd_init(&arg.fds_e);
-#ifdef HAVE_RB_FD_INIT
-    arg.fd = fd;
-    return (int)rb_ensure(try_wait_connectable, (VALUE)&arg,
-			  wait_connectable_ensure,(VALUE)&arg);
-#else
-    return wait_connectable0(fd, &arg.fds_w, &arg.fds_e);
-#endif
-}
-
-#ifdef __CYGWIN__
-#define WAIT_IN_PROGRESS 10
-#endif
-#ifdef __APPLE__
-#define WAIT_IN_PROGRESS 10
-#endif
-#ifdef __linux__
-/* returns correct error */
-#define WAIT_IN_PROGRESS 0
-#endif
-#ifndef WAIT_IN_PROGRESS
-/* BSD origin code apparently has a problem */
-#define WAIT_IN_PROGRESS 1
-#endif
-
-struct connect_arg {
-    int fd;
-    const struct sockaddr *sockaddr;
-    socklen_t len;
-};
-
-static VALUE
-connect_blocking(void *data)
-{
-    struct connect_arg *arg = data;
-    return (VALUE)connect(arg->fd, arg->sockaddr, arg->len);
-}
-
-#if defined(SOCKS) && !defined(SOCKS5)
-static VALUE
-socks_connect_blocking(void *data)
-{
-    struct connect_arg *arg = data;
-    return (VALUE)Rconnect(arg->fd, arg->sockaddr, arg->len);
-}
-#endif
-
-static int
-ruby_connect(int fd, const struct sockaddr *sockaddr, int len, int socks)
-{
-    int status;
-    rb_blocking_function_t *func = connect_blocking;
-    struct connect_arg arg;
-#if WAIT_IN_PROGRESS > 0
-    int wait_in_progress = -1;
-    int sockerr;
-    socklen_t sockerrlen;
-#endif
-
-    arg.fd = fd;
-    arg.sockaddr = sockaddr;
-    arg.len = len;
-#if defined(SOCKS) && !defined(SOCKS5)
-    if (socks) func = socks_connect_blocking;
-#endif
-    for (;;) {
-	status = (int)BLOCKING_REGION(func, &arg);
-	if (status < 0) {
-	    switch (errno) {
-	      case EAGAIN:
-#ifdef EINPROGRESS
-	      case EINPROGRESS:
-#endif
-#if WAIT_IN_PROGRESS > 0
-		sockerrlen = sizeof(sockerr);
-		status = getsockopt(fd, SOL_SOCKET, SO_ERROR, (void *)&sockerr, &sockerrlen);
-		if (status) break;
-		if (sockerr) {
-		    status = -1;
-		    errno = sockerr;
-		    break;
-		}
-#endif
-#ifdef EALREADY
-	      case EALREADY:
-#endif
-#if WAIT_IN_PROGRESS > 0
-		wait_in_progress = WAIT_IN_PROGRESS;
-#endif
-		status = wait_connectable(fd);
-		if (status) {
-		    break;
-		}
-		errno = 0;
-		continue;
-
-#if WAIT_IN_PROGRESS > 0
-	      case EINVAL:
-		if (wait_in_progress-- > 0) {
-		    /*
-		     * connect() after EINPROGRESS returns EINVAL on
-		     * some platforms, need to check true error
-		     * status.
-		     */
-		    sockerrlen = sizeof(sockerr);
-		    status = getsockopt(fd, SOL_SOCKET, SO_ERROR, (void *)&sockerr, &sockerrlen);
-		    if (!status && !sockerr) {
-			struct timeval tv = {0, 100000};
-			rb_thread_wait_for(tv);
-			continue;
-		    }
-		    status = -1;
-		    errno = sockerr;
-		}
-		break;
-#endif
-
-#ifdef EISCONN
-	      case EISCONN:
-		status = 0;
-		errno = 0;
-		break;
-#endif
-	      default:
-		break;
-	    }
-	}
-	return status;
-    }
-}
-
-struct inetsock_arg
-{
-    VALUE sock;
-    struct {
-	VALUE host, serv;
-	struct addrinfo *res;
-    } remote, local;
-    int type;
-    int fd;
-};
-
-static VALUE
-inetsock_cleanup(struct inetsock_arg *arg)
-{
-    if (arg->remote.res) {
-	freeaddrinfo(arg->remote.res);
-	arg->remote.res = 0;
-    }
-    if (arg->local.res) {
-	freeaddrinfo(arg->local.res);
-	arg->local.res = 0;
-    }
-    if (arg->fd >= 0) {
-	close(arg->fd);
-    }
-    return Qnil;
-}
-
-static VALUE
-init_inetsock_internal(struct inetsock_arg *arg)
-{
-    int type = arg->type;
-    struct addrinfo *res;
-    int fd, status = 0;
-    const char *syscall = 0;
-
-    arg->remote.res = sock_addrinfo(arg->remote.host, arg->remote.serv, SOCK_STREAM,
-				    (type == INET_SERVER) ? AI_PASSIVE : 0);
-    /*
-     * Maybe also accept a local address
-     */
-
-    if (type != INET_SERVER && (!NIL_P(arg->local.host) || !NIL_P(arg->local.serv))) {
-	arg->local.res = sock_addrinfo(arg->local.host, arg->local.serv, SOCK_STREAM, 0);
-    }
-
-    arg->fd = fd = -1;
-    for (res = arg->remote.res; res; res = res->ai_next) {
-	status = ruby_socket(res->ai_family,res->ai_socktype,res->ai_protocol);
-	syscall = "socket(2)";
-	fd = status;
-	if (fd < 0) {
-	    continue;
-	}
-	arg->fd = fd;
-	if (type == INET_SERVER) {
-#if !defined(_WIN32) && !defined(__CYGWIN__)
-	    status = 1;
-	    setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
-		       (char*)&status, sizeof(status));
-#endif
-	    status = bind(fd, res->ai_addr, res->ai_addrlen);
-	    syscall = "bind(2)";
-	}
-	else {
-	    if (arg->local.res) {
-		status = bind(fd, arg->local.res->ai_addr, arg->local.res->ai_addrlen);
-		syscall = "bind(2)";
-	    }
-
-	    if (status >= 0) {
-		status = ruby_connect(fd, res->ai_addr, res->ai_addrlen,
-				      (type == INET_SOCKS));
-		syscall = "connect(2)";
-	    }
-	}
-
-	if (status < 0) {
-	    close(fd);
-	    arg->fd = fd = -1;
-	    continue;
-	} else
-	    break;
-    }
-    if (status < 0) {
-	rb_sys_fail(syscall);
-    }
-
-    arg->fd = -1;
-
-    if (type == INET_SERVER)
-	listen(fd, 5);
-
-    /* create new instance */
-    return init_sock(arg->sock, fd);
-}
-
-static VALUE
-init_inetsock(VALUE sock, VALUE remote_host, VALUE remote_serv,
-	      VALUE local_host, VALUE local_serv, int type)
-{
-    struct inetsock_arg arg;
-    arg.sock = sock;
-    arg.remote.host = remote_host;
-    arg.remote.serv = remote_serv;
-    arg.remote.res = 0;
-    arg.local.host = local_host;
-    arg.local.serv = local_serv;
-    arg.local.res = 0;
-    arg.type = type;
-    arg.fd = -1;
-    return rb_ensure(init_inetsock_internal, (VALUE)&arg,
-		     inetsock_cleanup, (VALUE)&arg);
-}
-
-/*
- * call-seq:
- *    TCPSocket.new(remote_host, remote_port, local_host=nil, local_port=nil)
- *
- * Opens a TCP connection to +remote_host+ on +remote_port+.  If +local_host+
- * and +local_port+ are specified, then those parameters are used on the local
- * end to establish the connection.
- */
-static VALUE
-tcp_init(int argc, VALUE *argv, VALUE sock)
-{
-    VALUE remote_host, remote_serv;
-    VALUE local_host, local_serv;
-
-    rb_scan_args(argc, argv, "22", &remote_host, &remote_serv,
-			&local_host, &local_serv);
-
-    return init_inetsock(sock, remote_host, remote_serv,
-			local_host, local_serv, INET_CLIENT);
-}
-
-#ifdef SOCKS
-static VALUE
-socks_init(VALUE sock, VALUE host, VALUE serv)
-{
-    static init = 0;
-
-    if (init == 0) {
-	SOCKSinit("ruby");
-	init = 1;
-    }
-
-    return init_inetsock(sock, host, serv, Qnil, Qnil, INET_SOCKS);
-}
-
-#ifdef SOCKS5
-static VALUE
-socks_s_close(VALUE sock)
-{
-    rb_io_t *fptr;
-
-    if (rb_safe_level() >= 4 && !OBJ_TAINTED(sock)) {
-	rb_raise(rb_eSecurityError, "Insecure: can't close socket");
-    }
-    GetOpenFile(sock, fptr);
-    shutdown(fptr->fd, 2);
-    return rb_io_close(sock);
-}
-#endif
-#endif
-
-struct hostent_arg {
-    VALUE host;
-    struct addrinfo* addr;
-    VALUE (*ipaddr)(struct sockaddr*, size_t);
-};
-
-static VALUE
-make_hostent_internal(struct hostent_arg *arg)
-{
-    VALUE host = arg->host;
-    struct addrinfo* addr = arg->addr;
-    VALUE (*ipaddr)(struct sockaddr*, size_t) = arg->ipaddr;
-
-    struct addrinfo *ai;
-    struct hostent *h;
-    VALUE ary, names;
-    char **pch;
-    const char* hostp;
-    char hbuf[NI_MAXHOST];
-
-    ary = rb_ary_new();
-    if (addr->ai_canonname) {
-	hostp = addr->ai_canonname;
-    }
-    else {
-	hostp = host_str(host, hbuf, sizeof(hbuf), NULL);
-    }
-    rb_ary_push(ary, rb_str_new2(hostp));
-
-    if (addr->ai_canonname && (h = gethostbyname(addr->ai_canonname))) {
-	names = rb_ary_new();
-	if (h->h_aliases != NULL) {
-	    for (pch = h->h_aliases; *pch; pch++) {
-		rb_ary_push(names, rb_str_new2(*pch));
-	    }
-	}
-    }
-    else {
-	names = rb_ary_new2(0);
-    }
-    rb_ary_push(ary, names);
-    rb_ary_push(ary, INT2NUM(addr->ai_family));
-    for (ai = addr; ai; ai = ai->ai_next) {
-	rb_ary_push(ary, (*ipaddr)(ai->ai_addr, ai->ai_addrlen));
-    }
-
-    return ary;
-}
-
-static VALUE
-make_hostent(VALUE host, struct addrinfo *addr, VALUE (*ipaddr)(struct sockaddr *, size_t))
-{
-    struct hostent_arg arg;
-
-    arg.host = host;
-    arg.addr = addr;
-    arg.ipaddr = ipaddr;
-    return rb_ensure(make_hostent_internal, (VALUE)&arg,
-		     RUBY_METHOD_FUNC(freeaddrinfo), (VALUE)addr);
-}
-
-static VALUE
-tcp_sockaddr(struct sockaddr *addr, size_t len)
-{
-    return make_ipaddr(addr);
-}
-
-/*
- * call-seq:
- *   TCPSocket.gethostbyname(hostname) => [official_hostname, alias_hostnames, address_family, *address_list]
- *
- * Lookups host information by _hostname_.
- *
- *   TCPSocket.gethostbyname("localhost")
- *   #=> ["localhost", ["hal"], 2, "127.0.0.1"]
- *
- */
-static VALUE
-tcp_s_gethostbyname(VALUE obj, VALUE host)
-{
-    rb_secure(3);
-    return make_hostent(host, sock_addrinfo(host, Qnil, SOCK_STREAM, AI_CANONNAME),
-			tcp_sockaddr);
-}
-
-/*
- * call-seq:
- *   TCPServer.new([hostname,] port)                    => tcpserver
- *
- * Creates a new server socket bound to _port_.
- *
- * If _hostname_ is given, the socket is bound to it.
- *
- *   serv = TCPServer.new("127.0.0.1", 28561)
- *   s = serv.accept
- *   s.puts Time.now
- *   s.close
- */
-static VALUE
-tcp_svr_init(int argc, VALUE *argv, VALUE sock)
-{
-    VALUE arg1, arg2;
-
-    if (rb_scan_args(argc, argv, "11", &arg1, &arg2) == 2)
-	return init_inetsock(sock, arg1, arg2, Qnil, Qnil, INET_SERVER);
-    else
-	return init_inetsock(sock, Qnil, arg1, Qnil, Qnil, INET_SERVER);
-}
-
-static void
-make_fd_nonblock(int fd)
-{
-    int flags;
-#ifdef F_GETFL
-    flags = fcntl(fd, F_GETFL);
-    if (flags == -1) {
-        rb_sys_fail(0);
-    }
-#else
-    flags = 0;
-#endif
-    flags |= O_NONBLOCK;
-    if (fcntl(fd, F_SETFL, flags) == -1) {
-        rb_sys_fail(0);
-    }
-}
-
-static VALUE
-s_accept_nonblock(VALUE klass, rb_io_t *fptr, struct sockaddr *sockaddr, socklen_t *len)
-{
-    int fd2;
-
-    rb_secure(3);
-    rb_io_set_nonblock(fptr);
-    fd2 = accept(fptr->fd, (struct sockaddr*)sockaddr, len);
-    if (fd2 < 0) {
-        rb_sys_fail("accept(2)");
-    }
-    make_fd_nonblock(fd2);
-    return init_sock(rb_obj_alloc(klass), fd2);
-}
-
-struct accept_arg {
-    int fd;
-    struct sockaddr *sockaddr;
-    socklen_t *len;
-};
-
-static VALUE
-accept_blocking(void *data)
-{
-    struct accept_arg *arg = data;
-    return (VALUE)accept(arg->fd, arg->sockaddr, arg->len);
-}
-
-static VALUE
-s_accept(VALUE klass, int fd, struct sockaddr *sockaddr, socklen_t *len)
-{
-    int fd2;
-    int retry = 0;
-    struct accept_arg arg;
-
-    rb_secure(3);
-    arg.fd = fd;
-    arg.sockaddr = sockaddr;
-    arg.len = len;
-  retry:
-    rb_thread_wait_fd(fd);
-    fd2 = BLOCKING_REGION(accept_blocking, &arg);
-    if (fd2 < 0) {
-	switch (errno) {
-	  case EMFILE:
-	  case ENFILE:
-	    if (retry) break;
-	    rb_gc();
-	    retry = 1;
-	    goto retry;
-	  default:
-	    if (!rb_io_wait_readable(fd)) break;
-	    retry = 0;
-	    goto retry;
-	}
-	rb_sys_fail(0);
-    }
-    if (!klass) return INT2NUM(fd2);
-    return init_sock(rb_obj_alloc(klass), fd2);
-}
-
-/*
- * call-seq:
- *   tcpserver.accept => tcpsocket
- *
- *   TCPServer.open("127.0.0.1", 14641) {|serv|
- *     s = serv.accept
- *     s.puts Time.now
- *     s.close
- *   }
- *   
- */
-static VALUE
-tcp_accept(VALUE sock)
-{
-    rb_io_t *fptr;
-    struct sockaddr_storage from;
-    socklen_t fromlen;
- 
-    GetOpenFile(sock, fptr);
-    fromlen = sizeof(from);
-    return s_accept(rb_cTCPSocket, fptr->fd,
-		    (struct sockaddr*)&from, &fromlen);
-}
-
-/*
- * call-seq:
- * 	tcpserver.accept_nonblock => tcpsocket
- * 
- * Accepts an incoming connection using accept(2) after
- * O_NONBLOCK is set for the underlying file descriptor.
- * It returns an accepted TCPSocket for the incoming connection.
- * 
- * === Example
- * 	require 'socket'
- * 	serv = TCPServer.new(2202)
- * 	begin # emulate blocking accept
- * 	  sock = serv.accept_nonblock
- * 	rescue Errno::EAGAIN, Errno::EWOULDBLOCK, Errno::ECONNABORTED, Errno::EPROTO, Errno::EINTR
- * 	  IO.select([serv])
- * 	  retry
- * 	end
- * 	# sock is an accepted socket.
- * 
- * Refer to Socket#accept for the exceptions that may be thrown if the call
- * to TCPServer#accept_nonblock fails. 
- *
- * TCPServer#accept_nonblock may raise any error corresponding to accept(2) failure,
- * including Errno::EWOULDBLOCK.
- * 
- * === See
- * * TCPServer#accept
- * * Socket#accept
- */
-static VALUE
-tcp_accept_nonblock(VALUE sock)
-{
-    rb_io_t *fptr;
-    struct sockaddr_storage from;
-    socklen_t fromlen;
-
-    GetOpenFile(sock, fptr);
-    fromlen = sizeof(from);
-    return s_accept_nonblock(rb_cTCPSocket, fptr,
-			     (struct sockaddr *)&from, &fromlen);
-}
-
-/*
- * call-seq:
- *   tcpserver.sysaccept => file_descriptor
- *
- * Returns a file descriptor of a accepted connection.
- *
- *   TCPServer.open("127.0.0.1", 28561) {|serv|
- *     fd = serv.sysaccept
- *     s = IO.for_fd(fd)       
- *     s.puts Time.now
- *     s.close
- *   }
- *
- */
-static VALUE
-tcp_sysaccept(VALUE sock)
-{
-    rb_io_t *fptr;
-    struct sockaddr_storage from;
-    socklen_t fromlen;
-
-    GetOpenFile(sock, fptr);
-    fromlen = sizeof(from);
-    return s_accept(0, fptr->fd, (struct sockaddr*)&from, &fromlen);
-}
-
-#ifdef HAVE_SYS_UN_H
-struct unixsock_arg {
-    struct sockaddr_un *sockaddr;
-    int fd;
-};
-
-static VALUE
-unixsock_connect_internal(struct unixsock_arg *arg)
-{
-    return (VALUE)ruby_connect(arg->fd, (struct sockaddr*)arg->sockaddr,
-			       sizeof(*arg->sockaddr), 0);
-}
-
-static VALUE
-init_unixsock(VALUE sock, VALUE path, int server)
-{
-    struct sockaddr_un sockaddr;
-    int fd, status;
-    rb_io_t *fptr;
-
-    SafeStringValue(path);
-    fd = ruby_socket(AF_UNIX, SOCK_STREAM, 0);
-    if (fd < 0) {
-	rb_sys_fail("socket(2)");
-    }
-
-    MEMZERO(&sockaddr, struct sockaddr_un, 1);
-    sockaddr.sun_family = AF_UNIX;
-    if (sizeof(sockaddr.sun_path) <= RSTRING_LEN(path)) {
-        rb_raise(rb_eArgError, "too long unix socket path (max: %dbytes)",
-            (int)sizeof(sockaddr.sun_path)-1);
-    }
-    memcpy(sockaddr.sun_path, RSTRING_PTR(path), RSTRING_LEN(path));
-
-    if (server) {
-        status = bind(fd, (struct sockaddr*)&sockaddr, sizeof(sockaddr));
-    }
-    else {
-	int prot;
-	struct unixsock_arg arg;
-	arg.sockaddr = &sockaddr;
-	arg.fd = fd;
-        status = rb_protect((VALUE(*)(VALUE))unixsock_connect_internal,
-			    (VALUE)&arg, &prot);
-	if (prot) {
-	    close(fd);
-	    rb_jump_tag(prot);
-	}
-    }
-
-    if (status < 0) {
-	close(fd);
-	rb_sys_fail(sockaddr.sun_path);
-    }
-
-    if (server) listen(fd, 5);
-
-    init_sock(sock, fd);
-    if (server) {
-	GetOpenFile(sock, fptr);
-        fptr->pathv = rb_str_new_frozen(path);
-    }
-
-    return sock;
-}
-#endif
-
-/*
- * call-seq:
- *   ipsocket.addr => [address_family, port, hostname, numeric_address] 
- *
- * Returns the local address as an array which contains
- * address_family, port, hostname and numeric_address. 
- *
- * hostname is obtained from numeric_address using reverse lookup.
- * If ipsocket.do_not_reverse_lookup is true,
- * hostname is same as numeric_address.
- *
- *   TCPSocket.open("www.ruby-lang.org", 80) {|sock|
- *     p sock.addr #=> ["AF_INET", 49429, "hal", "192.168.0.128"]
- *   }
- *
- */
-static VALUE
-ip_addr(VALUE sock)
-{
-    rb_io_t *fptr;
-    struct sockaddr_storage addr;
-    socklen_t len = sizeof addr;
-
-    GetOpenFile(sock, fptr);
-
-    if (getsockname(fptr->fd, (struct sockaddr*)&addr, &len) < 0)
-	rb_sys_fail("getsockname(2)");
-    return ipaddr((struct sockaddr*)&addr, fptr->mode & FMODE_NOREVLOOKUP);
-}
-
-/*
- * call-seq:
- *   ipsocket.peeraddr => [address_family, port, hostname, numeric_address] 
- *
- * Returns the remote address as an array which contains
- * address_family, port, hostname and numeric_address. 
- * It is defined for connection oritented socket such as TCPSocket.
- *
- *   TCPSocket.open("www.ruby-lang.org", 80) {|sock|
- *     p sock.peeraddr #=> ["AF_INET", 80, "carbon.ruby-lang.org", "221.186.184.68"]
- *   }
- *
- */
-static VALUE
-ip_peeraddr(VALUE sock)
-{
-    rb_io_t *fptr;
-    struct sockaddr_storage addr;
-    socklen_t len = sizeof addr;
-
-    GetOpenFile(sock, fptr);
-
-    if (getpeername(fptr->fd, (struct sockaddr*)&addr, &len) < 0)
-	rb_sys_fail("getpeername(2)");
-    return ipaddr((struct sockaddr*)&addr, fptr->mode & FMODE_NOREVLOOKUP);
-}
-
-/*
- * call-seq:
- *   ipsocket.recvfrom(maxlen)        => [mesg, ipaddr]
- *   ipsocket.recvfrom(maxlen, flags) => [mesg, ipaddr]
- *
- * Receives a message and return the message as a string and
- * an address which the message come from.
- *
- * _maxlen_ is the maximum number of bytes to receive.
- *
- * _flags_ should be a bitwise OR of Socket::MSG_* constants.
- *
- * ipaddr is same as IPSocket#{peeraddr,addr}.
- *
- *   u1 = UDPSocket.new
- *   u1.bind("127.0.0.1", 4913)
- *   u2 = UDPSocket.new
- *   u2.send "uuuu", 0, "127.0.0.1", 4913
- *   p u1.recvfrom(10) #=> ["uuuu", ["AF_INET", 33230, "localhost", "127.0.0.1"]]
- *   
- */
-static VALUE
-ip_recvfrom(int argc, VALUE *argv, VALUE sock)
-{
-    return s_recvfrom(sock, argc, argv, RECV_IP);
-}
-
-/*
- * call-seq:
- *   IPSocket.getaddress(host)        => ipaddress
- *
- * Lookups IP address of _host_.
- *
- *   IPSocket.getaddress("localhost")     #=> "127.0.0.1"
- *   IPSocket.getaddress("ip6-localhost") #=> "::1"
- *
- */
-static VALUE
-ip_s_getaddress(VALUE obj, VALUE host)
-{
-    struct sockaddr_storage addr;
-    struct addrinfo *res = sock_addrinfo(host, Qnil, SOCK_STREAM, 0);
-
-    /* just take the first one */
-    memcpy(&addr, res->ai_addr, res->ai_addrlen);
-    freeaddrinfo(res);
-
-    return make_ipaddr((struct sockaddr*)&addr);
-}
-
-/*
- * call-seq:
- *   UDPSocket.new([address_family]) => socket
- *
- * Creates a new UDPSocket object.
- *
- * _address_family_ should be an integer, a string or a symbol:
- * Socket::AF_INET, "AF_INET", :INET, etc.
- *
- *   UDPSocket.new                   #=> #<UDPSocket:fd 3>
- *   UDPSocket.new(Socket::AF_INET6) #=> #<UDPSocket:fd 4>
- *
- */
-static VALUE
-udp_init(int argc, VALUE *argv, VALUE sock)
-{
-    VALUE arg;
-    int family = AF_INET;
-    int fd;
-
-    rb_secure(3);
-    if (rb_scan_args(argc, argv, "01", &arg) == 1) {
-	family = family_arg(arg);
-    }
-    fd = ruby_socket(family, SOCK_DGRAM, 0);
-    if (fd < 0) {
-	rb_sys_fail("socket(2) - udp");
-    }
-
-    return init_sock(sock, fd);
-}
-
-struct udp_arg
-{
-    struct addrinfo *res;
-    int fd;
-};
-
-static VALUE
-udp_connect_internal(struct udp_arg *arg)
-{
-    int fd = arg->fd;
-    struct addrinfo *res;
-
-    for (res = arg->res; res; res = res->ai_next) {
-	if (ruby_connect(fd, res->ai_addr, res->ai_addrlen, 0) >= 0) {
-	    return Qtrue;
-	}
-    }
-    return Qfalse;
-}
-
-/*
- * call-seq:
- *   udpsocket.connect(host, port) => 0
- *
- * Connects _udpsocket_ to _host_:_port_.
- *
- * This makes possible to send without destination address.
- *
- *   u1 = UDPSocket.new
- *   u1.bind("127.0.0.1", 4913)
- *   u2 = UDPSocket.new
- *   u2.connect("127.0.0.1", 4913)
- *   u2.send "uuuu", 0
- *   p u1.recvfrom(10) #=> ["uuuu", ["AF_INET", 33230, "localhost", "127.0.0.1"]]
- *
- */
-static VALUE
-udp_connect(VALUE sock, VALUE host, VALUE port)
-{
-    rb_io_t *fptr;
-    struct udp_arg arg;
-    VALUE ret;
-
-    rb_secure(3);
-    arg.res = sock_addrinfo(host, port, SOCK_DGRAM, 0);
-    GetOpenFile(sock, fptr);
-    arg.fd = fptr->fd;
-    ret = rb_ensure(udp_connect_internal, (VALUE)&arg,
-		    RUBY_METHOD_FUNC(freeaddrinfo), (VALUE)arg.res);
-    if (!ret) rb_sys_fail("connect(2)");
-    return INT2FIX(0);
-}
-
-/*
- * call-seq:
- *   udpsocket.bind(host, port) #=> 0
- *
- * Binds _udpsocket_ to _host_:_port_.
- *
- *   u1 = UDPSocket.new
- *   u1.bind("127.0.0.1", 4913)
- *   u1.send "message-to-self", 0, "127.0.0.1", 4913
- *   p u1.recvfrom(10) #=> ["message-to", ["AF_INET", 4913, "localhost", "127.0.0.1"]]
- *
- */
-static VALUE
-udp_bind(VALUE sock, VALUE host, VALUE port)
-{
-    rb_io_t *fptr;
-    struct addrinfo *res0, *res;
-
-    rb_secure(3);
-    res0 = sock_addrinfo(host, port, SOCK_DGRAM, 0);
-    GetOpenFile(sock, fptr);
-    for (res = res0; res; res = res->ai_next) {
-	if (bind(fptr->fd, res->ai_addr, res->ai_addrlen) < 0) {
-	    continue;
-	}
-	freeaddrinfo(res0);
-	return INT2FIX(0);
-    }
-    freeaddrinfo(res0);
-    rb_sys_fail("bind(2)");
-    return INT2FIX(0);
-}
-
-/*
- * call-seq:
- *   udpsocket.send(mesg, flags, host, port)  => numbytes_sent
- *   udpsocket.send(mesg, flags, sockaddr_to) => numbytes_sent
- *   udpsocket.send(mesg, flags)              => numbytes_sent
- *
- * Sends _mesg_ via _udpsocket_.
- * 
- * _flags_ should be a bitwise OR of Socket::MSG_* constants.
- *
- *   u1 = UDPSocket.new
- *   u1.bind("127.0.0.1", 4913)
- *
- *   u2 = UDPSocket.new
- *   u2.send "hi", 0, "127.0.0.1", 4913
- *
- *   mesg, addr = u1.recvfrom(10)
- *   u1.send mesg, 0, addr[3], addr[1]
- *
- *   p u2.recv(100) #=> "hi"
- *
- */
-static VALUE
-udp_send(int argc, VALUE *argv, VALUE sock)
-{
-    VALUE flags, host, port;
-    rb_io_t *fptr;
-    int n;
-    struct addrinfo *res0, *res;
-    struct send_arg arg;
-
-    if (argc == 2 || argc == 3) {
-	return bsock_send(argc, argv, sock);
-    }
-    rb_secure(4);
-    rb_scan_args(argc, argv, "4", &arg.mesg, &flags, &host, &port);
-
-    StringValue(arg.mesg);
-    res0 = sock_addrinfo(host, port, SOCK_DGRAM, 0);
-    GetOpenFile(sock, fptr);
-    arg.fd = fptr->fd;
-    arg.flags = NUM2INT(flags);
-    for (res = res0; res; res = res->ai_next) {
-      retry:
-	arg.to = res->ai_addr;
-	arg.tolen = res->ai_addrlen;
-	rb_thread_fd_writable(arg.fd);
-	n = (int)BLOCKING_REGION(sendto_blocking, &arg);
-	if (n >= 0) {
-	    freeaddrinfo(res0);
-	    return INT2FIX(n);
-	}
-	if (rb_io_wait_writable(fptr->fd)) {
-	    goto retry;
-	}
-    }
-    freeaddrinfo(res0);
-    rb_sys_fail("sendto(2)");
-    return INT2FIX(n);
-}
-
-/*
- * call-seq:
- * 	udpsocket.recvfrom_nonblock(maxlen) => [mesg, sender_inet_addr]
- * 	udpsocket.recvfrom_nonblock(maxlen, flags) => [mesg, sender_inet_addr]
- * 
- * Receives up to _maxlen_ bytes from +udpsocket+ using recvfrom(2) after
- * O_NONBLOCK is set for the underlying file descriptor.
- * If _maxlen_ is ommitted, its default value is 65536.
- * _flags_ is zero or more of the +MSG_+ options.
- * The first element of the results, _mesg_, is the data received.
- * The second element, _sender_inet_addr_, is an array to represent the sender address.
- *
- * When recvfrom(2) returns 0,
- * Socket#recvfrom_nonblock returns an empty string as data.
- * It means an empty packet.
- * 
- * === Parameters
- * * +maxlen+ - the number of bytes to receive from the socket
- * * +flags+ - zero or more of the +MSG_+ options 
- * 
- * === Example
- * 	require 'socket'
- * 	s1 = UDPSocket.new
- * 	s1.bind("127.0.0.1", 0)
- * 	s2 = UDPSocket.new
- * 	s2.bind("127.0.0.1", 0)
- * 	s2.connect(*s1.addr.values_at(3,1))
- * 	s1.connect(*s2.addr.values_at(3,1))
- * 	s1.send "aaa", 0
- * 	IO.select([s2]) # emulate blocking recvfrom
- * 	p s2.recvfrom_nonblock(10)  #=> ["aaa", ["AF_INET", 33302, "localhost.localdomain", "127.0.0.1"]]
- *
- * Refer to Socket#recvfrom for the exceptions that may be thrown if the call
- * to _recvfrom_nonblock_ fails. 
- *
- * UDPSocket#recvfrom_nonblock may raise any error corresponding to recvfrom(2) failure,
- * including Errno::EWOULDBLOCK.
- *
- * === See
- * * Socket#recvfrom
- */
-static VALUE
-udp_recvfrom_nonblock(int argc, VALUE *argv, VALUE sock)
-{
-    return s_recvfrom_nonblock(sock, argc, argv, RECV_IP);
-}
-
-#ifdef HAVE_SYS_UN_H
-/*
- * call-seq:
- *   UNIXSocket.new(path) => unixsocket
- *
- * Creates a new UNIX client socket connected to _path_.
- *
- *   s = UNIXSocket.new("/tmp/sock")
- *   s.send "hello", 0
- *   
- */
-static VALUE
-unix_init(VALUE sock, VALUE path)
-{
-    return init_unixsock(sock, path, 0);
-}
-
-static const char*
-unixpath(struct sockaddr_un *sockaddr, socklen_t len)
-{
-    if (sockaddr->sun_path < (char*)sockaddr + len)
-        return sockaddr->sun_path;
-    else
-        return "";
-}
-
-/*
- * call-seq:
- *   unixsocket.path => path
- *
- * Returns the path of the local address of unixsocket.
- *
- *   s = UNIXServer.new("/tmp/sock")
- *   p s.path #=> "/tmp/sock"
- *
- */
-static VALUE
-unix_path(VALUE sock)
-{
-    rb_io_t *fptr;
-
-    GetOpenFile(sock, fptr);
-    if (NIL_P(fptr->pathv)) {
-	struct sockaddr_un addr;
-	socklen_t len = sizeof(addr);
-	if (getsockname(fptr->fd, (struct sockaddr*)&addr, &len) < 0)
-	    rb_sys_fail(0);
-	fptr->pathv = rb_obj_freeze(rb_str_new_cstr(unixpath(&addr, len)));
-    }
-    return rb_str_dup(fptr->pathv);
-}
-
-/*
- * call-seq:
- *   UNIXServer.new(path) => unixserver
- *
- * Creates a new UNIX server socket bound to _path_.
- *
- *   serv = UNIXServer.new("/tmp/sock")
- *   s = serv.accept
- *   p s.read
- */
-static VALUE
-unix_svr_init(VALUE sock, VALUE path)
-{
-    return init_unixsock(sock, path, 1);
-}
-
-/*
- * call-seq:
- *   unixsocket.recvfrom(maxlen [, flags]) => [mesg, unixaddress]
- *
- * Receives a message via _unixsocket_.
- *
- * _maxlen_ is the maximum number of bytes to receive.
- *
- * _flags_ should be a bitwise OR of Socket::MSG_* constants.
- *
- *   s1 = Socket.new(:UNIX, :DGRAM, 0)
- *   s1_ai = AddrInfo.unix("/tmp/sock1")
- *   s1.bind(s1_ai)
- *
- *   s2 = Socket.new(:UNIX, :DGRAM, 0)
- *   s2_ai = AddrInfo.unix("/tmp/sock2")
- *   s2.bind(s2_ai)
- *   s3 = UNIXSocket.for_fd(s2.fileno)
- *
- *   s1.send "a", 0, s2_ai
- *   p s3.recvfrom(10) #=> ["a", ["AF_UNIX", "/tmp/sock1"]]
- *
- */
-static VALUE
-unix_recvfrom(int argc, VALUE *argv, VALUE sock)
-{
-    return s_recvfrom(sock, argc, argv, RECV_UNIX);
-}
-
-#if defined(HAVE_ST_MSG_CONTROL) && defined(SCM_RIGHTS)
-#define FD_PASSING_BY_MSG_CONTROL 1
-#else
-#define FD_PASSING_BY_MSG_CONTROL 0
-#endif
-
-#if defined(HAVE_ST_MSG_ACCRIGHTS)
-#define FD_PASSING_BY_MSG_ACCRIGHTS 1
-#else
-#define FD_PASSING_BY_MSG_ACCRIGHTS 0
-#endif
-
-struct iomsg_arg {
-    int fd;
-    struct msghdr msg;
-};
-
-static VALUE
-sendmsg_blocking(void *data)
-{
-    struct iomsg_arg *arg = data;
-    return sendmsg(arg->fd, &arg->msg, 0);
-}
-
-/*
- * call-seq:
- *   unixsocket.send_io(io) => nil
- *
- * Sends _io_ as file descriptor passing.
- *
- *   s1, s2 = UNIXSocket.pair
- *
- *   s1.send_io STDOUT
- *   stdout = s2.recv_io
- *
- *   p STDOUT.fileno #=> 1
- *   p stdout.fileno #=> 6
- *
- *   stdout.puts "hello" # outputs "hello\n" to standard output.
- */
-static VALUE
-unix_send_io(VALUE sock, VALUE val)
-{
-#if defined(HAVE_SENDMSG) && (FD_PASSING_BY_MSG_CONTROL || FD_PASSING_BY_MSG_ACCRIGHTS)
-    int fd;
-    rb_io_t *fptr;
-    struct iomsg_arg arg;
-    struct iovec vec[1];
-    char buf[1];
-
-#if FD_PASSING_BY_MSG_CONTROL
-    struct {
-	struct cmsghdr hdr;
-        char pad[8+sizeof(int)+8];
-    } cmsg;
-#endif
-
-    if (rb_obj_is_kind_of(val, rb_cIO)) {
-        rb_io_t *valfptr;
-	GetOpenFile(val, valfptr);
-	fd = valfptr->fd;
-    }
-    else if (FIXNUM_P(val)) {
-        fd = FIX2INT(val);
-    }
-    else {
-	rb_raise(rb_eTypeError, "neither IO nor file descriptor");
-    }
-
-    GetOpenFile(sock, fptr);
-
-    arg.msg.msg_name = NULL;
-    arg.msg.msg_namelen = 0;
-
-    /* Linux and Solaris doesn't work if msg_iov is NULL. */
-    buf[0] = '\0';
-    vec[0].iov_base = buf;
-    vec[0].iov_len = 1;
-    arg.msg.msg_iov = vec;
-    arg.msg.msg_iovlen = 1;
-
-#if FD_PASSING_BY_MSG_CONTROL
-    arg.msg.msg_control = (caddr_t)&cmsg;
-    arg.msg.msg_controllen = CMSG_LEN(sizeof(int));
-    arg.msg.msg_flags = 0;
-    MEMZERO((char*)&cmsg, char, sizeof(cmsg));
-    cmsg.hdr.cmsg_len = CMSG_LEN(sizeof(int));
-    cmsg.hdr.cmsg_level = SOL_SOCKET;
-    cmsg.hdr.cmsg_type = SCM_RIGHTS;
-    *(int *)CMSG_DATA(&cmsg.hdr) = fd;
-#else
-    arg.msg.msg_accrights = (caddr_t)&fd;
-    arg.msg.msg_accrightslen = sizeof(fd);
-#endif
-
-    arg.fd = fptr->fd;
-    rb_thread_fd_writable(arg.fd);
-    if ((int)BLOCKING_REGION(sendmsg_blocking, &arg) == -1)
-	rb_sys_fail("sendmsg(2)");
-
-    return Qnil;
-#else
-    rb_notimplement();
-    return Qnil;		/* not reached */
-#endif
-}
-
-static VALUE
-recvmsg_blocking(void *data)
-{
-    struct iomsg_arg *arg = data;
-    return recvmsg(arg->fd, &arg->msg, 0);
-}
-
-/*
- * call-seq:
- *   unixsocket.recv_io([klass [, mode]]) => io
- *
- *   UNIXServer.open("/tmp/sock") {|serv|
- *     UNIXSocket.open("/tmp/sock") {|c|  
- *       s = serv.accept
- *
- *       c.send_io STDOUT 
- *       stdout = s.recv_io 
- *
- *       p STDOUT.fileno #=> 1
- *       p stdout.fileno #=> 7
- *
- *       stdout.puts "hello" # outputs "hello\n" to standard output.
- *     }
- *   }
- *
- */
-static VALUE
-unix_recv_io(int argc, VALUE *argv, VALUE sock)
-{
-#if defined(HAVE_RECVMSG) && (FD_PASSING_BY_MSG_CONTROL || FD_PASSING_BY_MSG_ACCRIGHTS)
-    VALUE klass, mode;
-    rb_io_t *fptr;
-    struct iomsg_arg arg;
-    struct iovec vec[2];
-    char buf[1];
-
-    int fd;
-#if FD_PASSING_BY_MSG_CONTROL
-    struct {
-	struct cmsghdr hdr;
-        char pad[8+sizeof(int)+8];
-    } cmsg;
-#endif
-
-    rb_scan_args(argc, argv, "02", &klass, &mode);
-    if (argc == 0)
-	klass = rb_cIO;
-    if (argc <= 1)
-	mode = Qnil;
-
-    GetOpenFile(sock, fptr);
-
-    arg.msg.msg_name = NULL;
-    arg.msg.msg_namelen = 0;
-
-    vec[0].iov_base = buf;
-    vec[0].iov_len = sizeof(buf);
-    arg.msg.msg_iov = vec;
-    arg.msg.msg_iovlen = 1;
-
-#if FD_PASSING_BY_MSG_CONTROL
-    arg.msg.msg_control = (caddr_t)&cmsg;
-    arg.msg.msg_controllen = CMSG_SPACE(sizeof(int));
-    arg.msg.msg_flags = 0;
-    cmsg.hdr.cmsg_len = CMSG_LEN(sizeof(int));
-    cmsg.hdr.cmsg_level = SOL_SOCKET;
-    cmsg.hdr.cmsg_type = SCM_RIGHTS;
-    *(int *)CMSG_DATA(&cmsg.hdr) = -1;
-#else
-    arg.msg.msg_accrights = (caddr_t)&fd;
-    arg.msg.msg_accrightslen = sizeof(fd);
-    fd = -1;
-#endif
-
-    arg.fd = fptr->fd;
-    rb_thread_wait_fd(arg.fd);
-    if ((int)BLOCKING_REGION(recvmsg_blocking, &arg) == -1)
-	rb_sys_fail("recvmsg(2)");
-
-#if FD_PASSING_BY_MSG_CONTROL
-    if (arg.msg.msg_controllen < CMSG_LEN(sizeof(int))) {
-	rb_raise(rb_eSocket,
-		 "file descriptor was not passed (msg_controllen=%d smaller than CMSG_LEN(sizeof(int))=%d)",
-		 (int)arg.msg.msg_controllen, (int)CMSG_LEN(sizeof(int)));
-    }
-    if (CMSG_SPACE(sizeof(int)) < arg.msg.msg_controllen) {
-	rb_raise(rb_eSocket,
-		 "file descriptor was not passed (msg_controllen=%d bigger than CMSG_SPACE(sizeof(int))=%d)",
-		 (int)arg.msg.msg_controllen, (int)CMSG_SPACE(sizeof(int)));
-    }
-    if (cmsg.hdr.cmsg_len != CMSG_LEN(sizeof(int))) {
-	rb_raise(rb_eSocket,
-		 "file descriptor was not passed (cmsg_len=%d, %d expected)",
-		 (int)cmsg.hdr.cmsg_len, (int)CMSG_LEN(sizeof(int)));
-    }
-    if (cmsg.hdr.cmsg_level != SOL_SOCKET) {
-	rb_raise(rb_eSocket,
-		 "file descriptor was not passed (cmsg_level=%d, %d expected)",
-		 cmsg.hdr.cmsg_level, SOL_SOCKET);
-    }
-    if (cmsg.hdr.cmsg_type != SCM_RIGHTS) {
-	rb_raise(rb_eSocket,
-		 "file descriptor was not passed (cmsg_type=%d, %d expected)",
-		 cmsg.hdr.cmsg_type, SCM_RIGHTS);
-    }
-#else
-    if (arg.msg.msg_accrightslen != sizeof(fd)) {
-	rb_raise(rb_eSocket,
-		 "file descriptor was not passed (accrightslen) : %d != %d",
-		 arg.msg.msg_accrightslen, (int)sizeof(fd));
-    }
-#endif
-
-#if FD_PASSING_BY_MSG_CONTROL
-    fd = *(int *)CMSG_DATA(&cmsg.hdr);
-#endif
-
-    if (klass == Qnil)
-	return INT2FIX(fd);
-    else {
-	ID for_fd;
-	int ff_argc;
-	VALUE ff_argv[2];
-	CONST_ID(for_fd, "for_fd");
-	ff_argc = mode == Qnil ? 1 : 2;
-	ff_argv[0] = INT2FIX(fd);
-	ff_argv[1] = mode;
-        return rb_funcall2(klass, for_fd, ff_argc, ff_argv);
-    }
-#else
-    rb_notimplement();
-    return Qnil;		/* not reached */
-#endif
-}
-
-/*
- * call-seq:
- *   unixserver.accept => unixsocket
- *
- * Accepts a new connection.
- * It returns new UNIXSocket object.
- *
- *   UNIXServer.open("/tmp/sock") {|serv|
- *     UNIXSocket.open("/tmp/sock") {|c|
- *       s = serv.accept
- *       s.puts "hi"
- *       s.close
- *       p c.read #=> "hi\n"
- *     }
- *   }
- *
- */
-static VALUE
-unix_accept(VALUE sock)
-{
-    rb_io_t *fptr;
-    struct sockaddr_un from;
-    socklen_t fromlen;
-
-    GetOpenFile(sock, fptr);
-    fromlen = sizeof(struct sockaddr_un);
-    return s_accept(rb_cUNIXSocket, fptr->fd,
-		    (struct sockaddr*)&from, &fromlen);
-}
-
-/*
- * call-seq:
- * 	unixserver.accept_nonblock => unixsocket
- * 
- * Accepts an incoming connection using accept(2) after
- * O_NONBLOCK is set for the underlying file descriptor.
- * It returns an accepted UNIXSocket for the incoming connection.
- * 
- * === Example
- * 	require 'socket'
- * 	serv = UNIXServer.new("/tmp/sock")
- * 	begin # emulate blocking accept
- * 	  sock = serv.accept_nonblock
- * 	rescue Errno::EAGAIN, Errno::EWOULDBLOCK, Errno::ECONNABORTED, Errno::EPROTO, Errno::EINTR
- * 	  IO.select([serv])
- * 	  retry
- * 	end
- * 	# sock is an accepted socket.
- * 
- * Refer to Socket#accept for the exceptions that may be thrown if the call
- * to UNIXServer#accept_nonblock fails. 
- *
- * UNIXServer#accept_nonblock may raise any error corresponding to accept(2) failure,
- * including Errno::EWOULDBLOCK.
- * 
- * === See
- * * UNIXServer#accept
- * * Socket#accept
- */
-static VALUE
-unix_accept_nonblock(VALUE sock)
-{
-    rb_io_t *fptr;
-    struct sockaddr_un from;
-    socklen_t fromlen;
-
-    GetOpenFile(sock, fptr);
-    fromlen = sizeof(from);
-    return s_accept_nonblock(rb_cUNIXSocket, fptr,
-			     (struct sockaddr *)&from, &fromlen);
-}
-
-/*
- * call-seq:
- *   unixserver.sysaccept => file_descriptor
- *
- * Accepts a new connection.
- * It returns the new file descriptor which is an integer.
- *
- *   UNIXServer.open("/tmp/sock") {|serv|
- *     UNIXSocket.open("/tmp/sock") {|c|
- *       fd = serv.sysaccept
- *       s = IO.new(fd)
- *       s.puts "hi"
- *       s.close 
- *       p c.read #=> "hi\n"
- *     }
- *   }
- *
- */
-static VALUE
-unix_sysaccept(VALUE sock)
-{
-    rb_io_t *fptr;
-    struct sockaddr_un from;
-    socklen_t fromlen;
-
-    GetOpenFile(sock, fptr);
-    fromlen = sizeof(struct sockaddr_un);
-    return s_accept(0, fptr->fd, (struct sockaddr*)&from, &fromlen);
-}
-
-static VALUE
-unixaddr(struct sockaddr_un *sockaddr, socklen_t len)
-{
-    return rb_assoc_new(rb_str_new2("AF_UNIX"),
-                        rb_str_new2(unixpath(sockaddr, len)));
-}
-
-/*
- * call-seq:
- *   unixsocket.addr => [address_family, unix_path]
- *
- * Returns the local address as an array which contains
- * address_family and unix_path.
- *
- * Example
- *   serv = UNIXServer.new("/tmp/sock")
- *   p serv.addr #=> ["AF_UNIX", "/tmp/sock"]
- */
-static VALUE
-unix_addr(VALUE sock)
-{
-    rb_io_t *fptr;
-    struct sockaddr_un addr;
-    socklen_t len = sizeof addr;
-
-    GetOpenFile(sock, fptr);
-
-    if (getsockname(fptr->fd, (struct sockaddr*)&addr, &len) < 0)
-	rb_sys_fail("getsockname(2)");
-    return unixaddr(&addr, len);
-}
-
-/*
- * call-seq:
- *   unixsocket.peeraddr => [address_family, unix_path]
- *
- * Returns the remote address as an array which contains
- * address_family and unix_path.
- *
- * Example
- *   serv = UNIXServer.new("/tmp/sock")
- *   c = UNIXSocket.new("/tmp/sock")
- *   p c.peeraddr #=> ["AF_UNIX", "/tmp/sock"]
- */
-static VALUE
-unix_peeraddr(VALUE sock)
-{
-    rb_io_t *fptr;
-    struct sockaddr_un addr;
-    socklen_t len = sizeof addr;
-
-    GetOpenFile(sock, fptr);
-
-    if (getpeername(fptr->fd, (struct sockaddr*)&addr, &len) < 0)
-	rb_sys_fail("getpeername(2)");
-    return unixaddr(&addr, len);
-}
-#endif
+#include "rubysocket.h"
 
 static void
 setup_domain_and_type(VALUE domain, int *dv, VALUE type, int *tv)
@@ -4127,7 +90,7 @@ pair_yield(VALUE pair)
  *   p s2.recv(10) #=> "b"
  *
  */
-static VALUE
+VALUE
 sock_s_socketpair(VALUE klass, VALUE domain, VALUE type, VALUE protocol)
 {
 #if defined HAVE_SOCKETPAIR
@@ -4158,41 +121,6 @@ sock_s_socketpair(VALUE klass, VALUE domain, VALUE type, VALUE protocol)
 #endif
 }
 
-#ifdef HAVE_SYS_UN_H
-/*
- * call-seq:
- *   UNIXSocket.pair([type [, protocol]])       => [unixsocket1, unixsocket2]
- *   UNIXSocket.socketpair([type [, protocol]]) => [unixsocket1, unixsocket2]
- *
- * Creates a pair of sockets connected each other.
- *
- * _socktype_ should be a socket type such as: :STREAM, :DGRAM, :RAW, etc.
- *
- * _protocol_ should be a protocol defined in the domain.
- * 0 is default protocol for the domain.
- *
- *   s1, s2 = UNIXSocket.pair
- *   s1.send "a", 0
- *   s1.send "b", 0
- *   p s2.recv(10) #=> "ab"
- *
- */
-static VALUE
-unix_s_socketpair(int argc, VALUE *argv, VALUE klass)
-{
-    VALUE domain, type, protocol;
-    domain = INT2FIX(PF_UNIX);
-
-    rb_scan_args(argc, argv, "02", &type, &protocol);
-    if (argc == 0)
-	type = INT2FIX(SOCK_STREAM);
-    if (argc <= 1)
-	protocol = INT2FIX(0);
-
-    return sock_s_socketpair(klass, domain, type, protocol);
-}
-#endif
-
 /*
  * call-seq:
  * 	socket.connect(server_sockaddr) => 0
@@ -4540,7 +468,7 @@ sock_bind(VALUE sock, VALUE addr)
  * * listen manual pages on unix-based systems
  * * listen function in Microsoft's Winsock functions reference
  */
-static VALUE
+VALUE
 sock_listen(VALUE sock, VALUE log)
 {
     rb_io_t *fptr;
@@ -5458,20 +1386,6 @@ sock_s_unpack_sockaddr_un(VALUE self, VALUE addr)
 }
 #endif
 
-static void
-sock_define_const(const char *name, int value, VALUE mConst)
-{
-    rb_define_const(rb_cSocket, name, INT2NUM(value));
-    rb_define_const(mConst, name, INT2NUM(value));
-}
-
-static void
-sock_define_uconst(const char *name, unsigned int value, VALUE mConst)
-{
-    rb_define_const(rb_cSocket, name, UINT2NUM(value));
-    rb_define_const(mConst, name, UINT2NUM(value));
-}
-
 /*
  * Class +Socket+ provides access to the underlying operating system
  * socket implementations. It can be used to provide more operating system
@@ -5500,88 +1414,12 @@ sock_define_uconst(const char *name, unsigned int value, VALUE mConst)
 void
 Init_socket()
 {
-    VALUE mConst;
-
-    rb_eSocket = rb_define_class("SocketError", rb_eStandardError);
-
-    rb_cBasicSocket = rb_define_class("BasicSocket", rb_cIO);
-    rb_undef_method(rb_cBasicSocket, "initialize");
-
-    rb_define_singleton_method(rb_cBasicSocket, "do_not_reverse_lookup",
-			       bsock_do_not_rev_lookup, 0);
-    rb_define_singleton_method(rb_cBasicSocket, "do_not_reverse_lookup=",
-			       bsock_do_not_rev_lookup_set, 1);
-    rb_define_singleton_method(rb_cBasicSocket, "for_fd", bsock_s_for_fd, 1);
-
-    rb_define_method(rb_cBasicSocket, "close_read", bsock_close_read, 0);
-    rb_define_method(rb_cBasicSocket, "close_write", bsock_close_write, 0);
-    rb_define_method(rb_cBasicSocket, "shutdown", bsock_shutdown, -1);
-    rb_define_method(rb_cBasicSocket, "setsockopt", bsock_setsockopt, 3);
-    rb_define_method(rb_cBasicSocket, "getsockopt", bsock_getsockopt, 2);
-    rb_define_method(rb_cBasicSocket, "getsockname", bsock_getsockname, 0);
-    rb_define_method(rb_cBasicSocket, "getpeername", bsock_getpeername, 0);
-    rb_define_method(rb_cBasicSocket, "local_address", bsock_local_address, 0);
-    rb_define_method(rb_cBasicSocket, "remote_address", bsock_remote_address, 0);
-    rb_define_method(rb_cBasicSocket, "send", bsock_send, -1);
-    rb_define_method(rb_cBasicSocket, "recv", bsock_recv, -1);
-    rb_define_method(rb_cBasicSocket, "recv_nonblock", bsock_recv_nonblock, -1);
-    rb_define_method(rb_cBasicSocket, "do_not_reverse_lookup", bsock_do_not_reverse_lookup, 0);
-    rb_define_method(rb_cBasicSocket, "do_not_reverse_lookup=", bsock_do_not_reverse_lookup_set, 1);
-
-    rb_cIPSocket = rb_define_class("IPSocket", rb_cBasicSocket);
-    rb_define_method(rb_cIPSocket, "addr", ip_addr, 0);
-    rb_define_method(rb_cIPSocket, "peeraddr", ip_peeraddr, 0);
-    rb_define_method(rb_cIPSocket, "recvfrom", ip_recvfrom, -1);
-    rb_define_singleton_method(rb_cIPSocket, "getaddress", ip_s_getaddress, 1);
-
-    rb_cTCPSocket = rb_define_class("TCPSocket", rb_cIPSocket);
-    rb_define_singleton_method(rb_cTCPSocket, "gethostbyname", tcp_s_gethostbyname, 1);
-    rb_define_method(rb_cTCPSocket, "initialize", tcp_init, -1);
-
-#ifdef SOCKS
-    rb_cSOCKSSocket = rb_define_class("SOCKSSocket", rb_cTCPSocket);
-    rb_define_method(rb_cSOCKSSocket, "initialize", socks_init, 2);
-#ifdef SOCKS5
-    rb_define_method(rb_cSOCKSSocket, "close", socks_s_close, 0);
-#endif
-#endif
-
-    rb_cTCPServer = rb_define_class("TCPServer", rb_cTCPSocket);
-    rb_define_method(rb_cTCPServer, "accept", tcp_accept, 0);
-    rb_define_method(rb_cTCPServer, "accept_nonblock", tcp_accept_nonblock, 0);
-    rb_define_method(rb_cTCPServer, "sysaccept", tcp_sysaccept, 0);
-    rb_define_method(rb_cTCPServer, "initialize", tcp_svr_init, -1);
-    rb_define_method(rb_cTCPServer, "listen", sock_listen, 1);
-
-    rb_cUDPSocket = rb_define_class("UDPSocket", rb_cIPSocket);
-    rb_define_method(rb_cUDPSocket, "initialize", udp_init, -1);
-    rb_define_method(rb_cUDPSocket, "connect", udp_connect, 2);
-    rb_define_method(rb_cUDPSocket, "bind", udp_bind, 2);
-    rb_define_method(rb_cUDPSocket, "send", udp_send, -1);
-    rb_define_method(rb_cUDPSocket, "recvfrom_nonblock", udp_recvfrom_nonblock, -1);
-
-#ifdef HAVE_SYS_UN_H
-    rb_cUNIXSocket = rb_define_class("UNIXSocket", rb_cBasicSocket);
-    rb_define_method(rb_cUNIXSocket, "initialize", unix_init, 1);
-    rb_define_method(rb_cUNIXSocket, "path", unix_path, 0);
-    rb_define_method(rb_cUNIXSocket, "addr", unix_addr, 0);
-    rb_define_method(rb_cUNIXSocket, "peeraddr", unix_peeraddr, 0);
-    rb_define_method(rb_cUNIXSocket, "recvfrom", unix_recvfrom, -1);
-    rb_define_method(rb_cUNIXSocket, "send_io", unix_send_io, 1);
-    rb_define_method(rb_cUNIXSocket, "recv_io", unix_recv_io, -1);
-    rb_define_singleton_method(rb_cUNIXSocket, "socketpair", unix_s_socketpair, -1);
-    rb_define_singleton_method(rb_cUNIXSocket, "pair", unix_s_socketpair, -1);
-
-    rb_cUNIXServer = rb_define_class("UNIXServer", rb_cUNIXSocket);
-    rb_define_method(rb_cUNIXServer, "initialize", unix_svr_init, 1);
-    rb_define_method(rb_cUNIXServer, "accept", unix_accept, 0);
-    rb_define_method(rb_cUNIXServer, "accept_nonblock", unix_accept_nonblock, 0);
-    rb_define_method(rb_cUNIXServer, "sysaccept", unix_sysaccept, 0);
-    rb_define_method(rb_cUNIXServer, "listen", sock_listen, 1);
-#endif
+    Init_basicsocket();
 
     rb_cSocket = rb_define_class("Socket", rb_cBasicSocket);
 
+    Init_socket_init();
+
     rb_define_method(rb_cSocket, "initialize", sock_initialize, 3);
     rb_define_method(rb_cSocket, "connect", sock_connect, 1);
     rb_define_method(rb_cSocket, "connect_nonblock", sock_connect_nonblock, 1);
@@ -5611,39 +1449,4 @@ Init_socket()
     rb_define_singleton_method(rb_cSocket, "pack_sockaddr_un", sock_s_pack_sockaddr_un, 1);
     rb_define_singleton_method(rb_cSocket, "unpack_sockaddr_un", sock_s_unpack_sockaddr_un, 1);
 #endif
-
-    rb_cAddrInfo = rb_define_class("AddrInfo", rb_cData);
-    rb_define_alloc_func(rb_cAddrInfo, addrinfo_s_allocate);
-    rb_define_method(rb_cAddrInfo, "initialize", addrinfo_initialize, -1);
-    rb_define_method(rb_cAddrInfo, "inspect", addrinfo_inspect, 0);
-    rb_define_singleton_method(rb_cAddrInfo, "getaddrinfo", addrinfo_s_getaddrinfo, -1);
-    rb_define_singleton_method(rb_cAddrInfo, "ip", addrinfo_s_ip, 1);
-    rb_define_singleton_method(rb_cAddrInfo, "tcp", addrinfo_s_tcp, 2);
-    rb_define_singleton_method(rb_cAddrInfo, "udp", addrinfo_s_udp, 2);
-#ifdef HAVE_SYS_UN_H
-    rb_define_singleton_method(rb_cAddrInfo, "unix", addrinfo_s_unix, 1);
-#endif
-
-    rb_define_method(rb_cAddrInfo, "afamily", addrinfo_afamily, 0);
-    rb_define_method(rb_cAddrInfo, "pfamily", addrinfo_pfamily, 0);
-    rb_define_method(rb_cAddrInfo, "socktype", addrinfo_socktype, 0);
-    rb_define_method(rb_cAddrInfo, "protocol", addrinfo_protocol, 0);
-    rb_define_method(rb_cAddrInfo, "canonname", addrinfo_canonname, 0);
-
-    rb_define_method(rb_cAddrInfo, "ip?", addrinfo_ip_p, 0);
-    rb_define_method(rb_cAddrInfo, "ip_unpack", addrinfo_ip_unpack, 0);
-    rb_define_method(rb_cAddrInfo, "ipv4?", addrinfo_ipv4_p, 0);
-    rb_define_method(rb_cAddrInfo, "ipv6?", addrinfo_ipv6_p, 0);
-    rb_define_method(rb_cAddrInfo, "unix?", addrinfo_unix_p, 0);
-#ifdef HAVE_SYS_UN_H
-    rb_define_method(rb_cAddrInfo, "unix_path", addrinfo_unix_path, 0);
-#endif
-
-    rb_define_method(rb_cAddrInfo, "to_sockaddr", addrinfo_to_sockaddr, 0);
-
-    rb_define_method(rb_cAddrInfo, "getnameinfo", addrinfo_getnameinfo, -1);
-
-    /* constants */
-    mConst = rb_define_module_under(rb_cSocket, "Constants");
-    init_constants(mConst);
 }
diff --git a/ext/socket/sockssocket.c b/ext/socket/sockssocket.c
new file mode 100644
index 0000000000..640ddd2f4d
--- /dev/null
+++ b/ext/socket/sockssocket.c
@@ -0,0 +1,65 @@
+/************************************************
+
+  sockssocket.c -
+
+  created at: Thu Mar 31 12:21:29 JST 1994
+
+  Copyright (C) 1993-2007 Yukihiro Matsumoto
+
+************************************************/
+
+#include "rubysocket.h"
+
+#if defined(SOCKS) && !defined(SOCKS5)
+static VALUE
+socks_connect_blocking(void *data)
+{
+    struct connect_arg *arg = data;
+    return (VALUE)Rconnect(arg->fd, arg->sockaddr, arg->len);
+}
+#endif
+
+#ifdef SOCKS
+static VALUE
+socks_init(VALUE sock, VALUE host, VALUE serv)
+{
+    static init = 0;
+
+    if (init == 0) {
+	SOCKSinit("ruby");
+	init = 1;
+    }
+
+    return init_inetsock(sock, host, serv, Qnil, Qnil, INET_SOCKS);
+}
+
+#ifdef SOCKS5
+static VALUE
+socks_s_close(VALUE sock)
+{
+    rb_io_t *fptr;
+
+    if (rb_safe_level() >= 4 && !OBJ_TAINTED(sock)) {
+	rb_raise(rb_eSecurityError, "Insecure: can't close socket");
+    }
+    GetOpenFile(sock, fptr);
+    shutdown(fptr->fd, 2);
+    return rb_io_close(sock);
+}
+#endif
+#endif
+
+/*
+ * SOCKSSocket class
+ */
+void
+Init_sockssocket(void)
+{
+#ifdef SOCKS
+    rb_cSOCKSSocket = rb_define_class("SOCKSSocket", rb_cTCPSocket);
+    rb_define_method(rb_cSOCKSSocket, "initialize", socks_init, 2);
+#ifdef SOCKS5
+    rb_define_method(rb_cSOCKSSocket, "close", socks_s_close, 0);
+#endif
+#endif
+}
diff --git a/ext/socket/tcpserver.c b/ext/socket/tcpserver.c
new file mode 100644
index 0000000000..596a555daa
--- /dev/null
+++ b/ext/socket/tcpserver.c
@@ -0,0 +1,141 @@
+/************************************************
+
+  tcpserver.c -
+
+  created at: Thu Mar 31 12:21:29 JST 1994
+
+  Copyright (C) 1993-2007 Yukihiro Matsumoto
+
+************************************************/
+
+#include "rubysocket.h"
+
+/*
+ * call-seq:
+ *   TCPServer.new([hostname,] port)                    => tcpserver
+ *
+ * Creates a new server socket bound to _port_.
+ *
+ * If _hostname_ is given, the socket is bound to it.
+ *
+ *   serv = TCPServer.new("127.0.0.1", 28561)
+ *   s = serv.accept
+ *   s.puts Time.now
+ *   s.close
+ */
+static VALUE
+tcp_svr_init(int argc, VALUE *argv, VALUE sock)
+{
+    VALUE arg1, arg2;
+
+    if (rb_scan_args(argc, argv, "11", &arg1, &arg2) == 2)
+	return init_inetsock(sock, arg1, arg2, Qnil, Qnil, INET_SERVER);
+    else
+	return init_inetsock(sock, Qnil, arg1, Qnil, Qnil, INET_SERVER);
+}
+
+/*
+ * call-seq:
+ *   tcpserver.accept => tcpsocket
+ *
+ *   TCPServer.open("127.0.0.1", 14641) {|serv|
+ *     s = serv.accept
+ *     s.puts Time.now
+ *     s.close
+ *   }
+ *   
+ */
+static VALUE
+tcp_accept(VALUE sock)
+{
+    rb_io_t *fptr;
+    struct sockaddr_storage from;
+    socklen_t fromlen;
+ 
+    GetOpenFile(sock, fptr);
+    fromlen = sizeof(from);
+    return s_accept(rb_cTCPSocket, fptr->fd,
+		    (struct sockaddr*)&from, &fromlen);
+}
+
+/*
+ * call-seq:
+ * 	tcpserver.accept_nonblock => tcpsocket
+ * 
+ * Accepts an incoming connection using accept(2) after
+ * O_NONBLOCK is set for the underlying file descriptor.
+ * It returns an accepted TCPSocket for the incoming connection.
+ * 
+ * === Example
+ * 	require 'socket'
+ * 	serv = TCPServer.new(2202)
+ * 	begin # emulate blocking accept
+ * 	  sock = serv.accept_nonblock
+ * 	rescue Errno::EAGAIN, Errno::EWOULDBLOCK, Errno::ECONNABORTED, Errno::EPROTO, Errno::EINTR
+ * 	  IO.select([serv])
+ * 	  retry
+ * 	end
+ * 	# sock is an accepted socket.
+ * 
+ * Refer to Socket#accept for the exceptions that may be thrown if the call
+ * to TCPServer#accept_nonblock fails. 
+ *
+ * TCPServer#accept_nonblock may raise any error corresponding to accept(2) failure,
+ * including Errno::EWOULDBLOCK.
+ * 
+ * === See
+ * * TCPServer#accept
+ * * Socket#accept
+ */
+static VALUE
+tcp_accept_nonblock(VALUE sock)
+{
+    rb_io_t *fptr;
+    struct sockaddr_storage from;
+    socklen_t fromlen;
+
+    GetOpenFile(sock, fptr);
+    fromlen = sizeof(from);
+    return s_accept_nonblock(rb_cTCPSocket, fptr,
+			     (struct sockaddr *)&from, &fromlen);
+}
+
+/*
+ * call-seq:
+ *   tcpserver.sysaccept => file_descriptor
+ *
+ * Returns a file descriptor of a accepted connection.
+ *
+ *   TCPServer.open("127.0.0.1", 28561) {|serv|
+ *     fd = serv.sysaccept
+ *     s = IO.for_fd(fd)       
+ *     s.puts Time.now
+ *     s.close
+ *   }
+ *
+ */
+static VALUE
+tcp_sysaccept(VALUE sock)
+{
+    rb_io_t *fptr;
+    struct sockaddr_storage from;
+    socklen_t fromlen;
+
+    GetOpenFile(sock, fptr);
+    fromlen = sizeof(from);
+    return s_accept(0, fptr->fd, (struct sockaddr*)&from, &fromlen);
+}
+
+/*
+ * TCPServer class
+ */
+void
+Init_tcpserver(void)
+{
+    rb_cTCPServer = rb_define_class("TCPServer", rb_cTCPSocket);
+    rb_define_method(rb_cTCPServer, "accept", tcp_accept, 0);
+    rb_define_method(rb_cTCPServer, "accept_nonblock", tcp_accept_nonblock, 0);
+    rb_define_method(rb_cTCPServer, "sysaccept", tcp_sysaccept, 0);
+    rb_define_method(rb_cTCPServer, "initialize", tcp_svr_init, -1);
+    rb_define_method(rb_cTCPServer, "listen", sock_listen, 1);
+}
diff --git a/ext/socket/tcpsocket.c b/ext/socket/tcpsocket.c
new file mode 100644
index 0000000000..76d938aaf4
--- /dev/null
+++ b/ext/socket/tcpsocket.c
@@ -0,0 +1,67 @@
+/************************************************
+
+  tcpsocket.c -
+
+  created at: Thu Mar 31 12:21:29 JST 1994
+
+  Copyright (C) 1993-2007 Yukihiro Matsumoto
+
+************************************************/
+
+#include "rubysocket.h"
+
+/*
+ * call-seq:
+ *    TCPSocket.new(remote_host, remote_port, local_host=nil, local_port=nil)
+ *
+ * Opens a TCP connection to +remote_host+ on +remote_port+.  If +local_host+
+ * and +local_port+ are specified, then those parameters are used on the local
+ * end to establish the connection.
+ */
+static VALUE
+tcp_init(int argc, VALUE *argv, VALUE sock)
+{
+    VALUE remote_host, remote_serv;
+    VALUE local_host, local_serv;
+
+    rb_scan_args(argc, argv, "22", &remote_host, &remote_serv,
+			&local_host, &local_serv);
+
+    return init_inetsock(sock, remote_host, remote_serv,
+			local_host, local_serv, INET_CLIENT);
+}
+
+static VALUE
+tcp_sockaddr(struct sockaddr *addr, size_t len)
+{
+    return make_ipaddr(addr);
+}
+
+/*
+ * call-seq:
+ *   TCPSocket.gethostbyname(hostname) => [official_hostname, alias_hostnames, address_family, *address_list]
+ *
+ * Lookups host information by _hostname_.
+ *
+ *   TCPSocket.gethostbyname("localhost")
+ *   #=> ["localhost", ["hal"], 2, "127.0.0.1"]
+ *
+ */
+static VALUE
+tcp_s_gethostbyname(VALUE obj, VALUE host)
+{
+    rb_secure(3);
+    return make_hostent(host, sock_addrinfo(host, Qnil, SOCK_STREAM, AI_CANONNAME),
+			tcp_sockaddr);
+}
+
+/*
+ * TCPSocket class
+ */
+void
+Init_tcpsocket(void)
+{
+    rb_cTCPSocket = rb_define_class("TCPSocket", rb_cIPSocket);
+    rb_define_singleton_method(rb_cTCPSocket, "gethostbyname", tcp_s_gethostbyname, 1);
+    rb_define_method(rb_cTCPSocket, "initialize", tcp_init, -1);
+}
diff --git a/ext/socket/udpsocket.c b/ext/socket/udpsocket.c
new file mode 100644
index 0000000000..77fde987c4
--- /dev/null
+++ b/ext/socket/udpsocket.c
@@ -0,0 +1,252 @@
+/************************************************
+
+  udpsocket.c -
+
+  created at: Thu Mar 31 12:21:29 JST 1994
+
+  Copyright (C) 1993-2007 Yukihiro Matsumoto
+
+************************************************/
+
+#include "rubysocket.h"
+
+/*
+ * call-seq:
+ *   UDPSocket.new([address_family]) => socket
+ *
+ * Creates a new UDPSocket object.
+ *
+ * _address_family_ should be an integer, a string or a symbol:
+ * Socket::AF_INET, "AF_INET", :INET, etc.
+ *
+ *   UDPSocket.new                   #=> #<UDPSocket:fd 3>
+ *   UDPSocket.new(Socket::AF_INET6) #=> #<UDPSocket:fd 4>
+ *
+ */
+static VALUE
+udp_init(int argc, VALUE *argv, VALUE sock)
+{
+    VALUE arg;
+    int family = AF_INET;
+    int fd;
+
+    rb_secure(3);
+    if (rb_scan_args(argc, argv, "01", &arg) == 1) {
+	family = family_arg(arg);
+    }
+    fd = ruby_socket(family, SOCK_DGRAM, 0);
+    if (fd < 0) {
+	rb_sys_fail("socket(2) - udp");
+    }
+
+    return init_sock(sock, fd);
+}
+
+struct udp_arg
+{
+    struct addrinfo *res;
+    int fd;
+};
+
+static VALUE
+udp_connect_internal(struct udp_arg *arg)
+{
+    int fd = arg->fd;
+    struct addrinfo *res;
+
+    for (res = arg->res; res; res = res->ai_next) {
+	if (ruby_connect(fd, res->ai_addr, res->ai_addrlen, 0) >= 0) {
+	    return Qtrue;
+	}
+    }
+    return Qfalse;
+}
+
+/*
+ * call-seq:
+ *   udpsocket.connect(host, port) => 0
+ *
+ * Connects _udpsocket_ to _host_:_port_.
+ *
+ * This makes possible to send without destination address.
+ *
+ *   u1 = UDPSocket.new
+ *   u1.bind("127.0.0.1", 4913)
+ *   u2 = UDPSocket.new
+ *   u2.connect("127.0.0.1", 4913)
+ *   u2.send "uuuu", 0
+ *   p u1.recvfrom(10) #=> ["uuuu", ["AF_INET", 33230, "localhost", "127.0.0.1"]]
+ *
+ */
+static VALUE
+udp_connect(VALUE sock, VALUE host, VALUE port)
+{
+    rb_io_t *fptr;
+    struct udp_arg arg;
+    VALUE ret;
+
+    rb_secure(3);
+    arg.res = sock_addrinfo(host, port, SOCK_DGRAM, 0);
+    GetOpenFile(sock, fptr);
+    arg.fd = fptr->fd;
+    ret = rb_ensure(udp_connect_internal, (VALUE)&arg,
+		    RUBY_METHOD_FUNC(freeaddrinfo), (VALUE)arg.res);
+    if (!ret) rb_sys_fail("connect(2)");
+    return INT2FIX(0);
+}
+
+/*
+ * call-seq:
+ *   udpsocket.bind(host, port) #=> 0
+ *
+ * Binds _udpsocket_ to _host_:_port_.
+ *
+ *   u1 = UDPSocket.new
+ *   u1.bind("127.0.0.1", 4913)
+ *   u1.send "message-to-self", 0, "127.0.0.1", 4913
+ *   p u1.recvfrom(10) #=> ["message-to", ["AF_INET", 4913, "localhost", "127.0.0.1"]]
+ *
+ */
+static VALUE
+udp_bind(VALUE sock, VALUE host, VALUE port)
+{
+    rb_io_t *fptr;
+    struct addrinfo *res0, *res;
+
+    rb_secure(3);
+    res0 = sock_addrinfo(host, port, SOCK_DGRAM, 0);
+    GetOpenFile(sock, fptr);
+    for (res = res0; res; res = res->ai_next) {
+	if (bind(fptr->fd, res->ai_addr, res->ai_addrlen) < 0) {
+	    continue;
+	}
+	freeaddrinfo(res0);
+	return INT2FIX(0);
+    }
+    freeaddrinfo(res0);
+    rb_sys_fail("bind(2)");
+    return INT2FIX(0);
+}
+
+/*
+ * call-seq:
+ *   udpsocket.send(mesg, flags, host, port)  => numbytes_sent
+ *   udpsocket.send(mesg, flags, sockaddr_to) => numbytes_sent
+ *   udpsocket.send(mesg, flags)              => numbytes_sent
+ *
+ * Sends _mesg_ via _udpsocket_.
+ * 
+ * _flags_ should be a bitwise OR of Socket::MSG_* constants.
+ *
+ *   u1 = UDPSocket.new
+ *   u1.bind("127.0.0.1", 4913)
+ *
+ *   u2 = UDPSocket.new
+ *   u2.send "hi", 0, "127.0.0.1", 4913
+ *
+ *   mesg, addr = u1.recvfrom(10)
+ *   u1.send mesg, 0, addr[3], addr[1]
+ *
+ *   p u2.recv(100) #=> "hi"
+ *
+ */
+static VALUE
+udp_send(int argc, VALUE *argv, VALUE sock)
+{
+    VALUE flags, host, port;
+    rb_io_t *fptr;
+    int n;
+    struct addrinfo *res0, *res;
+    struct send_arg arg;
+
+    if (argc == 2 || argc == 3) {
+	return bsock_send(argc, argv, sock);
+    }
+    rb_secure(4);
+    rb_scan_args(argc, argv, "4", &arg.mesg, &flags, &host, &port);
+
+    StringValue(arg.mesg);
+    res0 = sock_addrinfo(host, port, SOCK_DGRAM, 0);
+    GetOpenFile(sock, fptr);
+    arg.fd = fptr->fd;
+    arg.flags = NUM2INT(flags);
+    for (res = res0; res; res = res->ai_next) {
+      retry:
+	arg.to = res->ai_addr;
+	arg.tolen = res->ai_addrlen;
+	rb_thread_fd_writable(arg.fd);
+	n = (int)BLOCKING_REGION(sendto_blocking, &arg);
+	if (n >= 0) {
+	    freeaddrinfo(res0);
+	    return INT2FIX(n);
+	}
+	if (rb_io_wait_writable(fptr->fd)) {
+	    goto retry;
+	}
+    }
+    freeaddrinfo(res0);
+    rb_sys_fail("sendto(2)");
+    return INT2FIX(n);
+}
+
+/*
+ * call-seq:
+ * 	udpsocket.recvfrom_nonblock(maxlen) => [mesg, sender_inet_addr]
+ * 	udpsocket.recvfrom_nonblock(maxlen, flags) => [mesg, sender_inet_addr]
+ * 
+ * Receives up to _maxlen_ bytes from +udpsocket+ using recvfrom(2) after
+ * O_NONBLOCK is set for the underlying file descriptor.
+ * If _maxlen_ is ommitted, its default value is 65536.
+ * _flags_ is zero or more of the +MSG_+ options.
+ * The first element of the results, _mesg_, is the data received.
+ * The second element, _sender_inet_addr_, is an array to represent the sender address.
+ *
+ * When recvfrom(2) returns 0,
+ * Socket#recvfrom_nonblock returns an empty string as data.
+ * It means an empty packet.
+ * 
+ * === Parameters
+ * * +maxlen+ - the number of bytes to receive from the socket
+ * * +flags+ - zero or more of the +MSG_+ options 
+ * 
+ * === Example
+ * 	require 'socket'
+ * 	s1 = UDPSocket.new
+ * 	s1.bind("127.0.0.1", 0)
+ * 	s2 = UDPSocket.new
+ * 	s2.bind("127.0.0.1", 0)
+ * 	s2.connect(*s1.addr.values_at(3,1))
+ * 	s1.connect(*s2.addr.values_at(3,1))
+ * 	s1.send "aaa", 0
+ * 	IO.select([s2]) # emulate blocking recvfrom
+ * 	p s2.recvfrom_nonblock(10)  #=> ["aaa", ["AF_INET", 33302, "localhost.localdomain", "127.0.0.1"]]
+ *
+ * Refer to Socket#recvfrom for the exceptions that may be thrown if the call
+ * to _recvfrom_nonblock_ fails. 
+ *
+ * UDPSocket#recvfrom_nonblock may raise any error corresponding to recvfrom(2) failure,
+ * including Errno::EWOULDBLOCK.
+ *
+ * === See
+ * * Socket#recvfrom
+ */
+static VALUE
+udp_recvfrom_nonblock(int argc, VALUE *argv, VALUE sock)
+{
+    return s_recvfrom_nonblock(sock, argc, argv, RECV_IP);
+}
+
+/*
+ * UDPSocket class
+ */
+void
+Init_udpsocket(void)
+{
+    rb_cUDPSocket = rb_define_class("UDPSocket", rb_cIPSocket);
+    rb_define_method(rb_cUDPSocket, "initialize", udp_init, -1);
+    rb_define_method(rb_cUDPSocket, "connect", udp_connect, 2);
+    rb_define_method(rb_cUDPSocket, "bind", udp_bind, 2);
+    rb_define_method(rb_cUDPSocket, "send", udp_send, -1);
+    rb_define_method(rb_cUDPSocket, "recvfrom_nonblock", udp_recvfrom_nonblock, -1);
+}
+
diff --git a/ext/socket/unixserver.c b/ext/socket/unixserver.c
new file mode 100644
index 0000000000..74d91872eb
--- /dev/null
+++ b/ext/socket/unixserver.c
@@ -0,0 +1,148 @@
+/************************************************
+
+  unixserver.c -
+
+  created at: Thu Mar 31 12:21:29 JST 1994
+
+  Copyright (C) 1993-2007 Yukihiro Matsumoto
+
+************************************************/
+
+#include "rubysocket.h"
+
+#ifdef HAVE_SYS_UN_H
+/*
+ * call-seq:
+ *   UNIXServer.new(path) => unixserver
+ *
+ * Creates a new UNIX server socket bound to _path_.
+ *
+ *   serv = UNIXServer.new("/tmp/sock")
+ *   s = serv.accept
+ *   p s.read
+ */
+static VALUE
+unix_svr_init(VALUE sock, VALUE path)
+{
+    return init_unixsock(sock, path, 1);
+}
+
+/*
+ * call-seq:
+ *   unixserver.accept => unixsocket
+ *
+ * Accepts a new connection.
+ * It returns new UNIXSocket object.
+ *
+ *   UNIXServer.open("/tmp/sock") {|serv|
+ *     UNIXSocket.open("/tmp/sock") {|c|
+ *       s = serv.accept
+ *       s.puts "hi"
+ *       s.close
+ *       p c.read #=> "hi\n"
+ *     }
+ *   }
+ *
+ */
+static VALUE
+unix_accept(VALUE sock)
+{
+    rb_io_t *fptr;
+    struct sockaddr_un from;
+    socklen_t fromlen;
+
+    GetOpenFile(sock, fptr);
+    fromlen = sizeof(struct sockaddr_un);
+    return s_accept(rb_cUNIXSocket, fptr->fd,
+		    (struct sockaddr*)&from, &fromlen);
+}
+
+/*
+ * call-seq:
+ * 	unixserver.accept_nonblock => unixsocket
+ * 
+ * Accepts an incoming connection using accept(2) after
+ * O_NONBLOCK is set for the underlying file descriptor.
+ * It returns an accepted UNIXSocket for the incoming connection.
+ * 
+ * === Example
+ * 	require 'socket'
+ * 	serv = UNIXServer.new("/tmp/sock")
+ * 	begin # emulate blocking accept
+ * 	  sock = serv.accept_nonblock
+ * 	rescue Errno::EAGAIN, Errno::EWOULDBLOCK, Errno::ECONNABORTED, Errno::EPROTO, Errno::EINTR
+ * 	  IO.select([serv])
+ * 	  retry
+ * 	end
+ * 	# sock is an accepted socket.
+ * 
+ * Refer to Socket#accept for the exceptions that may be thrown if the call
+ * to UNIXServer#accept_nonblock fails. 
+ *
+ * UNIXServer#accept_nonblock may raise any error corresponding to accept(2) failure,
+ * including Errno::EWOULDBLOCK.
+ * 
+ * === See
+ * * UNIXServer#accept
+ * * Socket#accept
+ */
+static VALUE
+unix_accept_nonblock(VALUE sock)
+{
+    rb_io_t *fptr;
+    struct sockaddr_un from;
+    socklen_t fromlen;
+
+    GetOpenFile(sock, fptr);
+    fromlen = sizeof(from);
+    return s_accept_nonblock(rb_cUNIXSocket, fptr,
+			     (struct sockaddr *)&from, &fromlen);
+}
+
+/*
+ * call-seq:
+ *   unixserver.sysaccept => file_descriptor
+ *
+ * Accepts a new connection.
+ * It returns the new file descriptor which is an integer.
+ *
+ *   UNIXServer.open("/tmp/sock") {|serv|
+ *     UNIXSocket.open("/tmp/sock") {|c|
+ *       fd = serv.sysaccept
+ *       s = IO.new(fd)
+ *       s.puts "hi"
+ *       s.close 
+ *       p c.read #=> "hi\n"
+ *     }
+ *   }
+ *
+ */
+static VALUE
+unix_sysaccept(VALUE sock)
+{
+    rb_io_t *fptr;
+    struct sockaddr_un from;
+    socklen_t fromlen;
+
+    GetOpenFile(sock, fptr);
+    fromlen = sizeof(struct sockaddr_un);
+    return s_accept(0, fptr->fd, (struct sockaddr*)&from, &fromlen);
+}
+
+#endif
+
+/*
+ * UNIXServer class
+ */
+void
+Init_unixserver(void)
+{
+#ifdef HAVE_SYS_UN_H
+    rb_cUNIXServer = rb_define_class("UNIXServer", rb_cUNIXSocket);
+    rb_define_method(rb_cUNIXServer, "initialize", unix_svr_init, 1);
+    rb_define_method(rb_cUNIXServer, "accept", unix_accept, 0);
+    rb_define_method(rb_cUNIXServer, "accept_nonblock", unix_accept_nonblock, 0);
+    rb_define_method(rb_cUNIXServer, "sysaccept", unix_sysaccept, 0);
+    rb_define_method(rb_cUNIXServer, "listen", sock_listen, 1);
+#endif
+}
diff --git a/ext/socket/unixsocket.c b/ext/socket/unixsocket.c
new file mode 100644
index 0000000000..7039a8219b
--- /dev/null
+++ b/ext/socket/unixsocket.c
@@ -0,0 +1,499 @@
+/************************************************
+
+  unixsocket.c -
+
+  created at: Thu Mar 31 12:21:29 JST 1994
+
+  Copyright (C) 1993-2007 Yukihiro Matsumoto
+
+************************************************/
+
+#include "rubysocket.h"
+
+#ifdef HAVE_SYS_UN_H
+struct unixsock_arg {
+    struct sockaddr_un *sockaddr;
+    int fd;
+};
+
+static VALUE
+unixsock_connect_internal(struct unixsock_arg *arg)
+{
+    return (VALUE)ruby_connect(arg->fd, (struct sockaddr*)arg->sockaddr,
+			       sizeof(*arg->sockaddr), 0);
+}
+
+VALUE
+init_unixsock(VALUE sock, VALUE path, int server)
+{
+    struct sockaddr_un sockaddr;
+    int fd, status;
+    rb_io_t *fptr;
+
+    SafeStringValue(path);
+    fd = ruby_socket(AF_UNIX, SOCK_STREAM, 0);
+    if (fd < 0) {
+	rb_sys_fail("socket(2)");
+    }
+
+    MEMZERO(&sockaddr, struct sockaddr_un, 1);
+    sockaddr.sun_family = AF_UNIX;
+    if (sizeof(sockaddr.sun_path) <= RSTRING_LEN(path)) {
+        rb_raise(rb_eArgError, "too long unix socket path (max: %dbytes)",
+            (int)sizeof(sockaddr.sun_path)-1);
+    }
+    memcpy(sockaddr.sun_path, RSTRING_PTR(path), RSTRING_LEN(path));
+
+    if (server) {
+        status = bind(fd, (struct sockaddr*)&sockaddr, sizeof(sockaddr));
+    }
+    else {
+	int prot;
+	struct unixsock_arg arg;
+	arg.sockaddr = &sockaddr;
+	arg.fd = fd;
+        status = rb_protect((VALUE(*)(VALUE))unixsock_connect_internal,
+			    (VALUE)&arg, &prot);
+	if (prot) {
+	    close(fd);
+	    rb_jump_tag(prot);
+	}
+    }
+
+    if (status < 0) {
+	close(fd);
+	rb_sys_fail(sockaddr.sun_path);
+    }
+
+    if (server) listen(fd, 5);
+
+    init_sock(sock, fd);
+    if (server) {
+	GetOpenFile(sock, fptr);
+        fptr->pathv = rb_str_new_frozen(path);
+    }
+
+    return sock;
+}
+#endif
+
+#ifdef HAVE_SYS_UN_H
+/*
+ * call-seq:
+ *   UNIXSocket.new(path) => unixsocket
+ *
+ * Creates a new UNIX client socket connected to _path_.
+ *
+ *   s = UNIXSocket.new("/tmp/sock")
+ *   s.send "hello", 0
+ *   
+ */
+static VALUE
+unix_init(VALUE sock, VALUE path)
+{
+    return init_unixsock(sock, path, 0);
+}
+
+/*
+ * call-seq:
+ *   unixsocket.path => path
+ *
+ * Returns the path of the local address of unixsocket.
+ *
+ *   s = UNIXServer.new("/tmp/sock")
+ *   p s.path #=> "/tmp/sock"
+ *
+ */
+static VALUE
+unix_path(VALUE sock)
+{
+    rb_io_t *fptr;
+
+    GetOpenFile(sock, fptr);
+    if (NIL_P(fptr->pathv)) {
+	struct sockaddr_un addr;
+	socklen_t len = sizeof(addr);
+	if (getsockname(fptr->fd, (struct sockaddr*)&addr, &len) < 0)
+	    rb_sys_fail(0);
+	fptr->pathv = rb_obj_freeze(rb_str_new_cstr(unixpath(&addr, len)));
+    }
+    return rb_str_dup(fptr->pathv);
+}
+
+/*
+ * call-seq:
+ *   unixsocket.recvfrom(maxlen [, flags]) => [mesg, unixaddress]
+ *
+ * Receives a message via _unixsocket_.
+ *
+ * _maxlen_ is the maximum number of bytes to receive.
+ *
+ * _flags_ should be a bitwise OR of Socket::MSG_* constants.
+ *
+ *   s1 = Socket.new(:UNIX, :DGRAM, 0)
+ *   s1_ai = AddrInfo.unix("/tmp/sock1")
+ *   s1.bind(s1_ai)
+ *
+ *   s2 = Socket.new(:UNIX, :DGRAM, 0)
+ *   s2_ai = AddrInfo.unix("/tmp/sock2")
+ *   s2.bind(s2_ai)
+ *   s3 = UNIXSocket.for_fd(s2.fileno)
+ *
+ *   s1.send "a", 0, s2_ai
+ *   p s3.recvfrom(10) #=> ["a", ["AF_UNIX", "/tmp/sock1"]]
+ *
+ */
+static VALUE
+unix_recvfrom(int argc, VALUE *argv, VALUE sock)
+{
+    return s_recvfrom(sock, argc, argv, RECV_UNIX);
+}
+
+#if defined(HAVE_ST_MSG_CONTROL) && defined(SCM_RIGHTS)
+#define FD_PASSING_BY_MSG_CONTROL 1
+#else
+#define FD_PASSING_BY_MSG_CONTROL 0
+#endif
+
+#if defined(HAVE_ST_MSG_ACCRIGHTS)
+#define FD_PASSING_BY_MSG_ACCRIGHTS 1
+#else
+#define FD_PASSING_BY_MSG_ACCRIGHTS 0
+#endif
+
+struct iomsg_arg {
+    int fd;
+    struct msghdr msg;
+};
+
+static VALUE
+sendmsg_blocking(void *data)
+{
+    struct iomsg_arg *arg = data;
+    return sendmsg(arg->fd, &arg->msg, 0);
+}
+
+/*
+ * call-seq:
+ *   unixsocket.send_io(io) => nil
+ *
+ * Sends _io_ as file descriptor passing.
+ *
+ *   s1, s2 = UNIXSocket.pair
+ *
+ *   s1.send_io STDOUT
+ *   stdout = s2.recv_io
+ *
+ *   p STDOUT.fileno #=> 1
+ *   p stdout.fileno #=> 6
+ *
+ *   stdout.puts "hello" # outputs "hello\n" to standard output.
+ */
+static VALUE
+unix_send_io(VALUE sock, VALUE val)
+{
+#if defined(HAVE_SENDMSG) && (FD_PASSING_BY_MSG_CONTROL || FD_PASSING_BY_MSG_ACCRIGHTS)
+    int fd;
+    rb_io_t *fptr;
+    struct iomsg_arg arg;
+    struct iovec vec[1];
+    char buf[1];
+
+#if FD_PASSING_BY_MSG_CONTROL
+    struct {
+	struct cmsghdr hdr;
+        char pad[8+sizeof(int)+8];
+    } cmsg;
+#endif
+
+    if (rb_obj_is_kind_of(val, rb_cIO)) {
+        rb_io_t *valfptr;
+	GetOpenFile(val, valfptr);
+	fd = valfptr->fd;
+    }
+    else if (FIXNUM_P(val)) {
+        fd = FIX2INT(val);
+    }
+    else {
+	rb_raise(rb_eTypeError, "neither IO nor file descriptor");
+    }
+
+    GetOpenFile(sock, fptr);
+
+    arg.msg.msg_name = NULL;
+    arg.msg.msg_namelen = 0;
+
+    /* Linux and Solaris doesn't work if msg_iov is NULL. */
+    buf[0] = '\0';
+    vec[0].iov_base = buf;
+    vec[0].iov_len = 1;
+    arg.msg.msg_iov = vec;
+    arg.msg.msg_iovlen = 1;
+
+#if FD_PASSING_BY_MSG_CONTROL
+    arg.msg.msg_control = (caddr_t)&cmsg;
+    arg.msg.msg_controllen = CMSG_LEN(sizeof(int));
+    arg.msg.msg_flags = 0;
+    MEMZERO((char*)&cmsg, char, sizeof(cmsg));
+    cmsg.hdr.cmsg_len = CMSG_LEN(sizeof(int));
+    cmsg.hdr.cmsg_level = SOL_SOCKET;
+    cmsg.hdr.cmsg_type = SCM_RIGHTS;
+    *(int *)CMSG_DATA(&cmsg.hdr) = fd;
+#else
+    arg.msg.msg_accrights = (caddr_t)&fd;
+    arg.msg.msg_accrightslen = sizeof(fd);
+#endif
+
+    arg.fd = fptr->fd;
+    rb_thread_fd_writable(arg.fd);
+    if ((int)BLOCKING_REGION(sendmsg_blocking, &arg) == -1)
+	rb_sys_fail("sendmsg(2)");
+
+    return Qnil;
+#else
+    rb_notimplement();
+    return Qnil;		/* not reached */
+#endif
+}
+
+static VALUE
+recvmsg_blocking(void *data)
+{
+    struct iomsg_arg *arg = data;
+    return recvmsg(arg->fd, &arg->msg, 0);
+}
+
+/*
+ * call-seq:
+ *   unixsocket.recv_io([klass [, mode]]) => io
+ *
+ *   UNIXServer.open("/tmp/sock") {|serv|
+ *     UNIXSocket.open("/tmp/sock") {|c|  
+ *       s = serv.accept
+ *
+ *       c.send_io STDOUT 
+ *       stdout = s.recv_io 
+ *
+ *       p STDOUT.fileno #=> 1
+ *       p stdout.fileno #=> 7
+ *
+ *       stdout.puts "hello" # outputs "hello\n" to standard output.
+ *     }
+ *   }
+ *
+ */
+static VALUE
+unix_recv_io(int argc, VALUE *argv, VALUE sock)
+{
+#if defined(HAVE_RECVMSG) && (FD_PASSING_BY_MSG_CONTROL || FD_PASSING_BY_MSG_ACCRIGHTS)
+    VALUE klass, mode;
+    rb_io_t *fptr;
+    struct iomsg_arg arg;
+    struct iovec vec[2];
+    char buf[1];
+
+    int fd;
+#if FD_PASSING_BY_MSG_CONTROL
+    struct {
+	struct cmsghdr hdr;
+        char pad[8+sizeof(int)+8];
+    } cmsg;
+#endif
+
+    rb_scan_args(argc, argv, "02", &klass, &mode);
+    if (argc == 0)
+	klass = rb_cIO;
+    if (argc <= 1)
+	mode = Qnil;
+
+    GetOpenFile(sock, fptr);
+
+    arg.msg.msg_name = NULL;
+    arg.msg.msg_namelen = 0;
+
+    vec[0].iov_base = buf;
+    vec[0].iov_len = sizeof(buf);
+    arg.msg.msg_iov = vec;
+    arg.msg.msg_iovlen = 1;
+
+#if FD_PASSING_BY_MSG_CONTROL
+    arg.msg.msg_control = (caddr_t)&cmsg;
+    arg.msg.msg_controllen = CMSG_SPACE(sizeof(int));
+    arg.msg.msg_flags = 0;
+    cmsg.hdr.cmsg_len = CMSG_LEN(sizeof(int));
+    cmsg.hdr.cmsg_level = SOL_SOCKET;
+    cmsg.hdr.cmsg_type = SCM_RIGHTS;
+    *(int *)CMSG_DATA(&cmsg.hdr) = -1;
+#else
+    arg.msg.msg_accrights = (caddr_t)&fd;
+    arg.msg.msg_accrightslen = sizeof(fd);
+    fd = -1;
+#endif
+
+    arg.fd = fptr->fd;
+    rb_thread_wait_fd(arg.fd);
+    if ((int)BLOCKING_REGION(recvmsg_blocking, &arg) == -1)
+	rb_sys_fail("recvmsg(2)");
+
+#if FD_PASSING_BY_MSG_CONTROL
+    if (arg.msg.msg_controllen < CMSG_LEN(sizeof(int))) {
+	rb_raise(rb_eSocket,
+		 "file descriptor was not passed (msg_controllen=%d smaller than CMSG_LEN(sizeof(int))=%d)",
+		 (int)arg.msg.msg_controllen, (int)CMSG_LEN(sizeof(int)));
+    }
+    if (CMSG_SPACE(sizeof(int)) < arg.msg.msg_controllen) {
+	rb_raise(rb_eSocket,
+		 "file descriptor was not passed (msg_controllen=%d bigger than CMSG_SPACE(sizeof(int))=%d)",
+		 (int)arg.msg.msg_controllen, (int)CMSG_SPACE(sizeof(int)));
+    }
+    if (cmsg.hdr.cmsg_len != CMSG_LEN(sizeof(int))) {
+	rb_raise(rb_eSocket,
+		 "file descriptor was not passed (cmsg_len=%d, %d expected)",
+		 (int)cmsg.hdr.cmsg_len, (int)CMSG_LEN(sizeof(int)));
+    }
+    if (cmsg.hdr.cmsg_level != SOL_SOCKET) {
+	rb_raise(rb_eSocket,
+		 "file descriptor was not passed (cmsg_level=%d, %d expected)",
+		 cmsg.hdr.cmsg_level, SOL_SOCKET);
+    }
+    if (cmsg.hdr.cmsg_type != SCM_RIGHTS) {
+	rb_raise(rb_eSocket,
+		 "file descriptor was not passed (cmsg_type=%d, %d expected)",
+		 cmsg.hdr.cmsg_type, SCM_RIGHTS);
+    }
+#else
+    if (arg.msg.msg_accrightslen != sizeof(fd)) {
+	rb_raise(rb_eSocket,
+		 "file descriptor was not passed (accrightslen) : %d != %d",
+		 arg.msg.msg_accrightslen, (int)sizeof(fd));
+    }
+#endif
+
+#if FD_PASSING_BY_MSG_CONTROL
+    fd = *(int *)CMSG_DATA(&cmsg.hdr);
+#endif
+
+    if (klass == Qnil)
+	return INT2FIX(fd);
+    else {
+	ID for_fd;
+	int ff_argc;
+	VALUE ff_argv[2];
+	CONST_ID(for_fd, "for_fd");
+	ff_argc = mode == Qnil ? 1 : 2;
+	ff_argv[0] = INT2FIX(fd);
+	ff_argv[1] = mode;
+        return rb_funcall2(klass, for_fd, ff_argc, ff_argv);
+    }
+#else
+    rb_notimplement();
+    return Qnil;		/* not reached */
+#endif
+}
+
+/*
+ * call-seq:
+ *   unixsocket.addr => [address_family, unix_path]
+ *
+ * Returns the local address as an array which contains
+ * address_family and unix_path.
+ *
+ * Example
+ *   serv = UNIXServer.new("/tmp/sock")
+ *   p serv.addr #=> ["AF_UNIX", "/tmp/sock"]
+ */
+static VALUE
+unix_addr(VALUE sock)
+{
+    rb_io_t *fptr;
+    struct sockaddr_un addr;
+    socklen_t len = sizeof addr;
+
+    GetOpenFile(sock, fptr);
+
+    if (getsockname(fptr->fd, (struct sockaddr*)&addr, &len) < 0)
+	rb_sys_fail("getsockname(2)");
+    return unixaddr(&addr, len);
+}
+
+/*
+ * call-seq:
+ *   unixsocket.peeraddr => [address_family, unix_path]
+ *
+ * Returns the remote address as an array which contains
+ * address_family and unix_path.
+ *
+ * Example
+ *   serv = UNIXServer.new("/tmp/sock")
+ *   c = UNIXSocket.new("/tmp/sock")
+ *   p c.peeraddr #=> ["AF_UNIX", "/tmp/sock"]
+ */
+static VALUE
+unix_peeraddr(VALUE sock)
+{
+    rb_io_t *fptr;
+    struct sockaddr_un addr;
+    socklen_t len = sizeof addr;
+
+    GetOpenFile(sock, fptr);
+
+    if (getpeername(fptr->fd, (struct sockaddr*)&addr, &len) < 0)
+	rb_sys_fail("getpeername(2)");
+    return unixaddr(&addr, len);
+}
+#endif
+
+#ifdef HAVE_SYS_UN_H
+/*
+ * call-seq:
+ *   UNIXSocket.pair([type [, protocol]])       => [unixsocket1, unixsocket2]
+ *   UNIXSocket.socketpair([type [, protocol]]) => [unixsocket1, unixsocket2]
+ *
+ * Creates a pair of sockets connected each other.
+ *
+ * _socktype_ should be a socket type such as: :STREAM, :DGRAM, :RAW, etc.
+ *
+ * _protocol_ should be a protocol defined in the domain.
+ * 0 is default protocol for the domain.
+ *
+ *   s1, s2 = UNIXSocket.pair
+ *   s1.send "a", 0
+ *   s1.send "b", 0
+ *   p s2.recv(10) #=> "ab"
+ *
+ */
+static VALUE
+unix_s_socketpair(int argc, VALUE *argv, VALUE klass)
+{
+    VALUE domain, type, protocol;
+    domain = INT2FIX(PF_UNIX);
+
+    rb_scan_args(argc, argv, "02", &type, &protocol);
+    if (argc == 0)
+	type = INT2FIX(SOCK_STREAM);
+    if (argc <= 1)
+	protocol = INT2FIX(0);
+
+    return sock_s_socketpair(klass, domain, type, protocol);
+}
+#endif
+
+/*
+ * UNIXSocket class
+ */
+void
+Init_unixsocket(void)
+{
+#ifdef HAVE_SYS_UN_H
+    rb_cUNIXSocket = rb_define_class("UNIXSocket", rb_cBasicSocket);
+    rb_define_method(rb_cUNIXSocket, "initialize", unix_init, 1);
+    rb_define_method(rb_cUNIXSocket, "path", unix_path, 0);
+    rb_define_method(rb_cUNIXSocket, "addr", unix_addr, 0);
+    rb_define_method(rb_cUNIXSocket, "peeraddr", unix_peeraddr, 0);
+    rb_define_method(rb_cUNIXSocket, "recvfrom", unix_recvfrom, -1);
+    rb_define_method(rb_cUNIXSocket, "send_io", unix_send_io, 1);
+    rb_define_method(rb_cUNIXSocket, "recv_io", unix_recv_io, -1);
+    rb_define_singleton_method(rb_cUNIXSocket, "socketpair", unix_s_socketpair, -1);
+    rb_define_singleton_method(rb_cUNIXSocket, "pair", unix_s_socketpair, -1);
+#endif
+}