Fresh start

1 files changed, 695 insertions, 0 deletions

diff --git a/jni/ruby/ext/socket/extconf.rb b/jni/ruby/ext/socket/extconf.rb
new file mode 100644
index 0000000..6d15bba
--- /dev/null
+++ b/jni/ruby/ext/socket/extconf.rb
@@ -0,0 +1,695 @@
+require 'mkmf'
+
+AF_INET6_SOCKET_CREATION_TEST = <<EOF
+#include <sys/types.h>
+#ifndef _WIN32
+#include <sys/socket.h>
+#endif
+int
+main(void)
+{
+  socket(AF_INET6, SOCK_STREAM, 0);
+  return 0;
+}
+EOF
+
+GETADDRINFO_GETNAMEINFO_TEST = <<EOF
+#include <stdlib.h>
+
+#ifndef EXIT_SUCCESS
+#define EXIT_SUCCESS 0
+#endif
+#ifndef EXIT_FAILURE
+#define EXIT_FAILURE 1
+#endif
+
+#ifndef AF_LOCAL
+#define AF_LOCAL AF_UNIX
+#endif
+
+int
+main(void)
+{
+  int passive, gaierr, inet4 = 0, inet6 = 0;
+  struct addrinfo hints, *ai, *aitop;
+  char straddr[INET6_ADDRSTRLEN], strport[16];
+#ifdef _WIN32
+  WSADATA retdata;
+
+  WSAStartup(MAKEWORD(2, 0), &retdata);
+#endif
+
+  for (passive = 0; passive <= 1; passive++) {
+    memset(&hints, 0, sizeof(hints));
+    hints.ai_family = AF_UNSPEC;
+    hints.ai_protocol = IPPROTO_TCP;
+    hints.ai_flags = passive ? AI_PASSIVE : 0;
+    hints.ai_socktype = SOCK_STREAM;
+    if ((gaierr = getaddrinfo(NULL, "54321", &hints, &aitop)) != 0) {
+      (void)gai_strerror(gaierr);
+      goto bad;
+    }
+    for (ai = aitop; ai; ai = ai->ai_next) {
+      if (ai->ai_family == AF_LOCAL) continue;
+      if (ai->ai_addr == NULL)
+        goto bad;
+#if defined(_AIX)
+      if (ai->ai_family == AF_INET6 && passive) {
+        inet6++;
+        continue;
+      }
+      ai->ai_addr->sa_len = ai->ai_addrlen;
+      ai->ai_addr->sa_family = ai->ai_family;
+#endif
+      if (ai->ai_addrlen == 0 ||
+          getnameinfo(ai->ai_addr, ai->ai_addrlen,
+                      straddr, sizeof(straddr), strport, sizeof(strport),
+                      NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
+        goto bad;
+      }
+      if (strcmp(strport, "54321") != 0) {
+        goto bad;
+      }
+      switch (ai->ai_family) {
+      case AF_INET:
+        if (passive) {
+          if (strcmp(straddr, "0.0.0.0") != 0) {
+            goto bad;
+          }
+        } else {
+          if (strcmp(straddr, "127.0.0.1") != 0) {
+            goto bad;
+          }
+        }
+        inet4++;
+        break;
+      case AF_INET6:
+        if (passive) {
+          if (strcmp(straddr, "::") != 0) {
+            goto bad;
+          }
+        } else {
+          if (strcmp(straddr, "::1") != 0) {
+            goto bad;
+          }
+        }
+        inet6++;
+        break;
+      case AF_UNSPEC:
+        goto bad;
+        break;
+      default:
+        /* another family support? */
+        break;
+      }
+    }
+  }
+
+  if (!(inet4 == 0 || inet4 == 2))
+    goto bad;
+  if (!(inet6 == 0 || inet6 == 2))
+    goto bad;
+
+  if (aitop)
+    freeaddrinfo(aitop);
+  return EXIT_SUCCESS;
+
+ bad:
+  if (aitop)
+    freeaddrinfo(aitop);
+  return EXIT_FAILURE;
+}
+EOF
+
+RECVMSG_WITH_MSG_PEEK_ALLOCATE_FD_TEST = <<'EOF'
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <unistd.h>
+
+int main(int argc, char *argv[])
+{
+    int ps[2], sv[2];
+    int ret;
+    ssize_t ss;
+    int s_fd, r_fd;
+    struct msghdr s_msg, r_msg;
+    union {
+        struct cmsghdr hdr;
+        char dummy[CMSG_SPACE(sizeof(int))];
+    } s_cmsg, r_cmsg;
+    struct iovec s_iov, r_iov;
+    char s_buf[1], r_buf[1];
+    struct stat s_statbuf, r_statbuf;
+
+    ret = pipe(ps);
+    if (ret == -1) { perror("pipe"); exit(EXIT_FAILURE); }
+
+    s_fd = ps[0];
+
+    ret = socketpair(AF_UNIX, SOCK_DGRAM, 0, sv);
+    if (ret == -1) { perror("socketpair"); exit(EXIT_FAILURE); }
+
+    s_msg.msg_name = NULL;
+    s_msg.msg_namelen = 0;
+    s_msg.msg_iov = &s_iov;
+    s_msg.msg_iovlen = 1;
+    s_msg.msg_control = &s_cmsg;
+    s_msg.msg_controllen = CMSG_SPACE(sizeof(int));;
+    s_msg.msg_flags = 0;
+
+    s_iov.iov_base = &s_buf;
+    s_iov.iov_len = sizeof(s_buf);
+
+    s_buf[0] = 'a';
+
+    s_cmsg.hdr.cmsg_len = CMSG_LEN(sizeof(int));
+    s_cmsg.hdr.cmsg_level = SOL_SOCKET;
+    s_cmsg.hdr.cmsg_type = SCM_RIGHTS;
+    memcpy(CMSG_DATA(&s_cmsg.hdr), (char *)&s_fd, sizeof(int));
+
+    ss = sendmsg(sv[0], &s_msg, 0);
+    if (ss == -1) { perror("sendmsg"); exit(EXIT_FAILURE); }
+
+    r_msg.msg_name = NULL;
+    r_msg.msg_namelen = 0;
+    r_msg.msg_iov = &r_iov;
+    r_msg.msg_iovlen = 1;
+    r_msg.msg_control = &r_cmsg;
+    r_msg.msg_controllen = CMSG_SPACE(sizeof(int));
+    r_msg.msg_flags = 0;
+
+    r_iov.iov_base = &r_buf;
+    r_iov.iov_len = sizeof(r_buf);
+
+    r_buf[0] = '0';
+
+    memset(&r_cmsg, 0xff, CMSG_SPACE(sizeof(int)));
+
+    ss = recvmsg(sv[1], &r_msg, MSG_PEEK);
+    if (ss == -1) { perror("recvmsg"); exit(EXIT_FAILURE); }
+
+    if (ss != 1) {
+        fprintf(stderr, "unexpected return value from recvmsg: %ld\n", (long)ss);
+        exit(EXIT_FAILURE);
+    }
+    if (r_buf[0] != 'a') {
+        fprintf(stderr, "unexpected return data from recvmsg: 0x%02x\n", r_buf[0]);
+        exit(EXIT_FAILURE);
+    }
+
+    if (r_msg.msg_controllen < CMSG_LEN(sizeof(int))) {
+        fprintf(stderr, "unexpected: r_msg.msg_controllen < CMSG_LEN(sizeof(int)) not hold: %ld\n",
+                (long)r_msg.msg_controllen);
+        exit(EXIT_FAILURE);
+    }
+    if (r_cmsg.hdr.cmsg_len < CMSG_LEN(sizeof(int))) {
+        fprintf(stderr, "unexpected: r_cmsg.hdr.cmsg_len < CMSG_LEN(sizeof(int)) not hold: %ld\n",
+                (long)r_cmsg.hdr.cmsg_len);
+        exit(EXIT_FAILURE);
+    }
+    memcpy((char *)&r_fd, CMSG_DATA(&r_cmsg.hdr), sizeof(int));
+
+    if (r_fd < 0) {
+        fprintf(stderr, "negative r_fd: %d\n", r_fd);
+        exit(EXIT_FAILURE);
+    }
+
+    if (r_fd == s_fd) {
+        fprintf(stderr, "r_fd and s_fd is same: %d\n", r_fd);
+        exit(EXIT_FAILURE);
+    }
+
+    ret = fstat(s_fd, &s_statbuf);
+    if (ret == -1) { perror("fstat(s_fd)"); exit(EXIT_FAILURE); }
+
+    ret = fstat(r_fd, &r_statbuf);
+    if (ret == -1) { perror("fstat(r_fd)"); exit(EXIT_FAILURE); }
+
+    if (s_statbuf.st_dev != r_statbuf.st_dev ||
+        s_statbuf.st_ino != r_statbuf.st_ino) {
+        fprintf(stderr, "dev/ino doesn't match: s_fd:%ld/%ld r_fd:%ld/%ld\n",
+                (long)s_statbuf.st_dev, (long)s_statbuf.st_ino,
+                (long)r_statbuf.st_dev, (long)r_statbuf.st_ino);
+        exit(EXIT_FAILURE);
+    }
+
+    return EXIT_SUCCESS;
+}
+EOF
+
+def test_recvmsg_with_msg_peek_creates_fds(headers)
+  case RUBY_PLATFORM
+  when /linux/
+    # Linux 2.6.38 allocate fds by recvmsg with MSG_PEEK.
+    close_fds = true
+  when /bsd|darwin/
+    # FreeBSD 8.2.0, NetBSD 5 and MacOS X Snow Leopard doesn't
+    # allocate fds by recvmsg with MSG_PEEK.
+    # [ruby-dev:44189]
+    # http://bugs.ruby-lang.org/issues/5075
+    close_fds = false
+  when /cygwin/
+    # Cygwin doesn't support fd passing.
+    # http://cygwin.com/ml/cygwin/2003-09/msg01808.html
+    close_fds = false
+  else
+    close_fds = nil
+  end
+  if !CROSS_COMPILING
+    if checking_for("recvmsg() with MSG_PEEK allocate file descriptors") {
+        try_run(cpp_include(headers) + RECVMSG_WITH_MSG_PEEK_ALLOCATE_FD_TEST)
+       }
+      if close_fds == false
+        warn "unexpected fd-passing recvmsg() with MSG_PEEK behavor on #{RUBY_PLATFORM}: fd allocation unexpected."
+      elsif close_fds == nil
+        puts "info: #{RUBY_PLATFORM} recvmsg() with MSG_PEEK allocates fds on fd-passing."
+      end
+      close_fds = true
+    else
+      if close_fds == true
+        warn "unexpected fd-passing recvmsg() with MSG_PEEK behavor on #{RUBY_PLATFORM}: fd allocation expected."
+      elsif close_fds == nil
+        puts "info: #{RUBY_PLATFORM}: recvmsg() with MSG_PEEK doesn't allocates fds on fd-passing."
+      end
+      close_fds = false
+    end
+  end
+  if close_fds == nil
+    abort <<EOS
+Fatal: cannot test fd-passing recvmsg() with MSG_PEEK behavor
+because cross-compilation for #{RUBY_PLATFORM}.
+If recvmsg() with MSG_PEEK allocates fds on fd passing:
+--enable-close-fds-by-recvmsg-with-peek
+If recvmsg() with MSG_PEEK doesn't allocate fds on fd passing:
+--disable-close-fds-by-recvmsg-with-peek
+EOS
+  end
+  close_fds
+end
+
+$INCFLAGS << " -I$(topdir) -I$(top_srcdir)"
+
+if /darwin/ =~ RUBY_PLATFORM
+  # For IPv6 extension header access on OS X 10.7+ [Bug #8517]
+  $CFLAGS << " -D__APPLE_USE_RFC_3542"
+end
+
+headers = []
+unless $mswin or $mingw
+  headers = %w<sys/types.h netdb.h string.h sys/socket.h netinet/in.h>
+end
+
+%w[
+  sys/uio.h
+  xti.h
+  netinet/in_systm.h
+  netinet/tcp.h
+  netinet/tcp_fsm.h
+  netinet/udp.h
+  arpa/inet.h
+  netpacket/packet.h
+  net/ethernet.h
+  sys/un.h
+  ifaddrs.h
+  sys/ioctl.h
+  sys/sockio.h
+  net/if.h
+  sys/param.h
+  sys/ucred.h
+  ucred.h
+  net/if_dl.h
+  arpa/nameser.h
+  resolv.h
+].each {|h|
+  if have_header(h, headers)
+    headers << h
+  end
+}
+
+have_struct_member("struct sockaddr", "sa_len", headers) # 4.4BSD
+have_struct_member("struct sockaddr_in", "sin_len", headers) # 4.4BSD
+have_struct_member("struct sockaddr_in6", "sin6_len", headers) # 4.4BSD
+
+if have_type("struct sockaddr_un", headers) # POSIX
+  have_struct_member("struct sockaddr_un", "sun_len", headers) # 4.4BSD
+end
+
+have_type("struct sockaddr_dl", headers) # AF_LINK address.  4.4BSD since Net2
+
+have_type("struct sockaddr_storage", headers)
+
+have_type("struct addrinfo", headers)
+
+if have_type("socklen_t", headers)
+  if try_static_assert("sizeof(socklen_t) >= sizeof(long)", headers)
+    $defs << "-DRSTRING_SOCKLEN=(socklen_t)RSTRING_LEN"
+  end
+end
+
+have_type("struct in_pktinfo", headers) {|src|
+  src.sub(%r'^/\*top\*/', '\&'"\n#if defined(IPPROTO_IP) && defined(IP_PKTINFO)") <<
+  "#else\n" << "#error\n" << ">>>>>> no in_pktinfo <<<<<<\n" << "#endif\n"
+} and have_struct_member("struct in_pktinfo", "ipi_spec_dst", headers)
+have_type("struct in6_pktinfo", headers) {|src|
+  src.sub(%r'^/\*top\*/', '\&'"\n#if defined(IPPROTO_IPV6) && defined(IPV6_PKTINFO)") <<
+  "#else\n" << "#error\n" << ">>>>>> no in6_pktinfo <<<<<<\n" << "#endif\n"
+}
+
+have_type("struct sockcred", headers)
+have_type("struct cmsgcred", headers)
+
+have_type("struct ip_mreq", headers) # 4.4BSD
+have_type("struct ip_mreqn", headers) # Linux 2.4
+have_type("struct ipv6_mreq", headers) # RFC 3493
+
+have_msg_control = nil
+have_msg_control = have_struct_member('struct msghdr', 'msg_control', headers) unless $mswin or $mingw
+have_struct_member('struct msghdr', 'msg_accrights', headers)
+
+if have_type("struct tcp_info", headers)
+  have_const("TCP_ESTABLISHED", headers)
+  have_const("TCP_SYN_SENT", headers)
+  have_const("TCP_SYN_RECV", headers)
+  have_const("TCP_FIN_WAIT1", headers)
+  have_const("TCP_FIN_WAIT2", headers)
+  have_const("TCP_TIME_WAIT", headers)
+  have_const("TCP_CLOSE", headers)
+  have_const("TCP_CLOSE_WAIT", headers)
+  have_const("TCP_LAST_ACK", headers)
+  have_const("TCP_LISTEN", headers)
+  have_const("TCP_CLOSING", headers)
+  have_struct_member('struct tcp_info', 'tcpi_state', headers)
+  if /solaris/ !~ RUBY_PLATFORM
+    have_struct_member('struct tcp_info', 'tcpi_ca_state', headers)
+  end
+  have_struct_member('struct tcp_info', 'tcpi_retransmits', headers)
+  have_struct_member('struct tcp_info', 'tcpi_probes', headers)
+  have_struct_member('struct tcp_info', 'tcpi_backoff', headers)
+  have_struct_member('struct tcp_info', 'tcpi_options', headers)
+  have_struct_member('struct tcp_info', 'tcpi_snd_wscale', headers)
+  have_struct_member('struct tcp_info', 'tcpi_rcv_wscale', headers)
+  have_struct_member('struct tcp_info', 'tcpi_rto', headers)
+  have_struct_member('struct tcp_info', 'tcpi_ato', headers)
+  have_struct_member('struct tcp_info', 'tcpi_snd_mss', headers)
+  have_struct_member('struct tcp_info', 'tcpi_rcv_mss', headers)
+  have_struct_member('struct tcp_info', 'tcpi_unacked', headers)
+  have_struct_member('struct tcp_info', 'tcpi_sacked', headers)
+  have_struct_member('struct tcp_info', 'tcpi_lost', headers)
+  have_struct_member('struct tcp_info', 'tcpi_retrans', headers)
+  have_struct_member('struct tcp_info', 'tcpi_fackets', headers)
+  have_struct_member('struct tcp_info', 'tcpi_last_data_sent', headers)
+  have_struct_member('struct tcp_info', 'tcpi_last_ack_sent', headers)
+  have_struct_member('struct tcp_info', 'tcpi_last_data_recv', headers)
+  have_struct_member('struct tcp_info', 'tcpi_last_ack_recv', headers)
+  have_struct_member('struct tcp_info', 'tcpi_pmtu', headers)
+  have_struct_member('struct tcp_info', 'tcpi_rcv_ssthresh', headers)
+  have_struct_member('struct tcp_info', 'tcpi_rtt', headers)
+  have_struct_member('struct tcp_info', 'tcpi_rttvar', headers)
+  have_struct_member('struct tcp_info', 'tcpi_snd_ssthresh', headers)
+  have_struct_member('struct tcp_info', 'tcpi_snd_cwnd', headers)
+  have_struct_member('struct tcp_info', 'tcpi_advmss', headers)
+  have_struct_member('struct tcp_info', 'tcpi_reordering', headers)
+  have_struct_member('struct tcp_info', 'tcpi_rcv_rtt', headers)
+  have_struct_member('struct tcp_info', 'tcpi_rcv_space', headers)
+  have_struct_member('struct tcp_info', 'tcpi_total_retrans', headers)
+
+  # FreeBSD extension
+  have_struct_member('struct tcp_info', 'tcpi_snd_wnd', headers)
+  have_struct_member('struct tcp_info', 'tcpi_snd_bwnd', headers)
+  have_struct_member('struct tcp_info', 'tcpi_snd_nxt', headers)
+  have_struct_member('struct tcp_info', 'tcpi_rcv_nxt', headers)
+  have_struct_member('struct tcp_info', 'tcpi_toe_tid', headers)
+  have_struct_member('struct tcp_info', 'tcpi_snd_rexmitpack', headers)
+  have_struct_member('struct tcp_info', 'tcpi_rcv_ooopack', headers)
+  have_struct_member('struct tcp_info', 'tcpi_snd_zerowin', headers)
+end
+
+case RUBY_PLATFORM
+when /mswin(32|64)|mingw/
+  test_func = "WSACleanup"
+  have_library("ws2_32", "WSACleanup", headers)
+when /cygwin/
+  test_func = "socket(0,0,0)"
+when /beos/
+  test_func = "socket(0,0,0)"
+  have_library("net", "socket(0,0,0)", headers)
+when /haiku/
+  test_func = "socket(0,0,0)"
+  have_library("network", "socket(0,0,0)", headers)
+when /i386-os2_emx/
+  test_func = "socket(0,0,0)"
+  have_library("socket", "socket(0,0,0)", headers)
+else
+  test_func = "socket(0,0,0)"
+  have_library("nsl", 't_open("", 0, (struct t_info *)NULL)', headers) # SunOS
+  have_library("socket", "socket(0,0,0)", headers) # SunOS
+end
+
+if have_func(test_func, headers)
+
+  have_func("sendmsg(0, (struct msghdr *)NULL, 0)", headers) # POSIX
+  have_recvmsg = have_func("recvmsg(0, (struct msghdr *)NULL, 0)", headers) # POSIX
+
+  have_func("freehostent((struct hostent *)NULL)", headers) # RFC 2553
+  have_func("freeaddrinfo((struct addrinfo *)NULL)", headers) # RFC 2553
+
+  if /haiku/ !~ RUBY_PLATFORM and
+     have_func("gai_strerror(0)", headers) # POSIX
+    if checking_for("gai_strerror() returns const pointer") {!try_compile(<<EOF)}
+#{cpp_include(headers)}
+#include <stdlib.h>
+void
+conftest_gai_strerror_is_const()
+{
+    *gai_strerror(0) = 0;
+}
+EOF
+      $defs << "-DGAI_STRERROR_CONST"
+    end
+  end
+
+  have_func("accept4", headers)
+
+  have_func('inet_ntop(0, (const void *)0, (char *)0, 0)', headers) or
+    have_func("inet_ntoa(*(struct in_addr *)NULL)", headers)
+  have_func('inet_pton(0, "", (void *)0)', headers) or
+    have_func('inet_aton("", (struct in_addr *)0)', headers)
+  have_func('getservbyport(0, "")', headers)
+  have_func("getifaddrs((struct ifaddrs **)NULL)", headers)
+
+  have_func("getpeereid", headers)
+
+  have_func("getpeerucred(0, (ucred_t **)NULL)", headers) # SunOS
+
+  have_func_decl = proc do |name, headers|
+    if !checking_for("declaration of #{name}()") {!%w[int void].all? {|ret| try_compile(<<EOF)}}
+#{cpp_include(headers)}
+#{ret} #{name}(void);
+EOF
+      $defs << "-DNEED_#{name.tr_cpp}_DECL"
+    end
+  end
+  if have_func('if_indextoname(0, "")', headers)
+    have_func_decl["if_indextoname"]
+  end
+  if have_func('if_nametoindex("")', headers)
+    have_func_decl["if_nametoindex"]
+  end
+
+  have_func("hsterror", headers)
+  have_func('getipnodebyname("", 0, 0, (int *)0)', headers) # RFC 2553
+  have_func('gethostbyname2("", 0)', headers) # RFC 2133
+  have_func("socketpair(0, 0, 0, 0)", headers)
+  unless have_func("gethostname((char *)0, 0)", headers)
+    have_func("uname((struct utsname *)NULL)", headers)
+  end
+
+  ipv6 = false
+  default_ipv6 = /beos|haiku/ !~ RUBY_PLATFORM
+  if enable_config("ipv6", default_ipv6)
+    if checking_for("ipv6") {try_link(AF_INET6_SOCKET_CREATION_TEST)}
+      $defs << "-DENABLE_IPV6" << "-DINET6"
+      ipv6 = true
+    end
+  end
+
+  if ipv6
+    if $mingw
+      $CPPFLAGS << " -D_WIN32_WINNT=0x501" unless $CPPFLAGS.include?("_WIN32_WINNT")
+    end
+    ipv6lib = nil
+    class << (fmt = "unknown")
+      def %(s) s || self end
+    end
+    idirs, ldirs = dir_config("inet6", %w[/usr/inet6 /usr/local/v6].find {|d| File.directory?(d)})
+    checking_for("ipv6 type", fmt) do
+      if have_macro("IPV6_INRIA_VERSION", "netinet/in.h")
+        "inria"
+      elsif have_macro("__KAME__", "netinet/in.h")
+        have_library(ipv6lib = "inet6")
+        "kame"
+      elsif have_macro("_TOSHIBA_INET6", "sys/param.h")
+        have_library(ipv6lib = "inet6") and "toshiba"
+      elsif have_macro("__V6D__", "sys/v6config.h")
+        have_library(ipv6lib = "v6") and "v6d"
+      elsif have_macro("_ZETA_MINAMI_INET6", "sys/param.h")
+        have_library(ipv6lib = "inet6") and "zeta"
+      elsif have_library("inet6")
+        "inet6"
+      end
+    end or not ipv6lib or abort <<EOS
+
+Fatal: no #{ipv6lib} library found.  cannot continue.
+You need to fetch lib#{ipv6lib}.a from appropriate
+ipv6 kit and compile beforehand.
+EOS
+  end
+
+  if !have_macro("IPPROTO_IPV6", headers) && have_const("IPPROTO_IPV6", headers)
+    IO.read(File.join(File.dirname(__FILE__), "mkconstants.rb")).sub(/\A.*^__END__$/m, '').split(/\r?\n/).grep(/\AIPPROTO_\w*/){$&}.each {|name|
+      have_const(name, headers) unless $defs.include?("-DHAVE_CONST_#{name.upcase}")
+    }
+  end
+
+  if enable_config("close-fds-by-recvmsg-with-peek") {
+      have_msg_control && have_recvmsg &&
+      have_const('AF_UNIX', headers) && have_const('SCM_RIGHTS', headers) &&
+      test_recvmsg_with_msg_peek_creates_fds(headers)
+     }
+    $defs << "-DFD_PASSING_WORK_WITH_RECVMSG_MSG_PEEK"
+  end
+
+  case enable_config("wide-getaddrinfo")
+  when true
+    getaddr_info_ok = :wide
+  when nil
+    if have_func("getnameinfo", headers) and have_func("getaddrinfo", headers)
+      getaddr_info_ok = :os
+      if !CROSS_COMPILING &&
+         !checking_for("system getaddrinfo working") {
+           try_run(cpp_include(headers) + GETADDRINFO_GETNAMEINFO_TEST)
+         }
+        getaddr_info_ok = :wide
+      end
+    else
+      getaddr_info_ok = :wide
+    end
+  when false
+    if have_func("getnameinfo", headers) and have_func("getaddrinfo", headers)
+      getaddr_info_ok = :os
+      if !CROSS_COMPILING &&
+         !checking_for("system getaddrinfo working") {
+           try_run(cpp_include(headers) + GETADDRINFO_GETNAMEINFO_TEST)
+         }
+        getaddr_info_ok = nil
+      end
+    else
+      getaddr_info_ok = nil
+    end
+  else
+    raise "unexpected enable_config() value"
+  end
+
+  if ipv6 and not getaddr_info_ok
+    abort <<EOS
+
+Fatal: --enable-ipv6 is specified, and your OS seems to support IPv6 feature.
+But your getaddrinfo() and getnameinfo() are appeared to be broken.  Sorry,
+you cannot compile IPv6 socket classes with broken these functions.
+You can try --enable-wide-getaddrinfo.
+EOS
+  end
+
+  case with_config("lookup-order-hack", "UNSPEC")
+  when "INET"
+    $defs << "-DLOOKUP_ORDER_HACK_INET"
+  when "INET6"
+    $defs << "-DLOOKUP_ORDER_HACK_INET6"
+  when "UNSPEC"
+    # nothing special
+  else
+    abort <<EOS
+
+Fatal: invalid value for --with-lookup-order-hack (expected INET, INET6 or UNSPEC)
+EOS
+  end
+
+  $objs = [
+    "init.#{$OBJEXT}",
+    "constants.#{$OBJEXT}",
+    "basicsocket.#{$OBJEXT}",
+    "socket.#{$OBJEXT}",
+    "ipsocket.#{$OBJEXT}",
+    "tcpsocket.#{$OBJEXT}",
+    "tcpserver.#{$OBJEXT}",
+    "sockssocket.#{$OBJEXT}",
+    "udpsocket.#{$OBJEXT}",
+    "unixsocket.#{$OBJEXT}",
+    "unixserver.#{$OBJEXT}",
+    "option.#{$OBJEXT}",
+    "ancdata.#{$OBJEXT}",
+    "raddrinfo.#{$OBJEXT}",
+    "ifaddr.#{$OBJEXT}"
+  ]
+
+  if getaddr_info_ok == :wide
+    if !have_type("struct in6_addr", headers) and have_type("struct in_addr6", headers)
+      $defs.pop(2)
+      $defs << "-Din_addr6=in6_addr"
+    end
+    if have_struct_member("struct in6_addr", "s6_addr8", headers)
+      $defs[-1] = "-Ds6_addr=s6_addr8"
+    end
+    if ipv6 == "kame" && have_struct_member("struct in6_addr", "s6_addr32", headers)
+      $defs[-1] = "-DFAITH"
+    end
+    $CPPFLAGS="-I. "+$CPPFLAGS
+    $objs += ["getaddrinfo.#{$OBJEXT}"]
+    $objs += ["getnameinfo.#{$OBJEXT}"]
+    $defs << "-DGETADDRINFO_EMU"
+  end
+
+  # workaround for recent Windows SDK
+  $defs << "-DIPPROTO_IPV6=IPPROTO_IPV6" if $defs.include?("-DHAVE_CONST_IPPROTO_IPV6") && !have_macro("IPPROTO_IPV6")
+
+  $distcleanfiles << "constants.h" << "constdefs.*"
+
+  if enable_config("socks", ENV["SOCKS_SERVER"])
+    if have_library("socks5", "SOCKSinit")
+      $defs << "-DSOCKS5" << "-DSOCKS"
+    elsif have_library("socks", "Rconnect")
+      $defs << "-DSOCKS"
+    end
+  end
+
+  hdr = "netinet6/in6.h"
+  if /darwin/ =~ RUBY_PLATFORM and !try_compile(<<"SRC", nil, :werror=>true)
+#include <netinet/in.h>
+int t(struct in6_addr *addr) {return IN6_IS_ADDR_UNSPECIFIED(addr);}
+SRC
+    print "fixing apple's netinet6/in6.rb ..."; $stdout.flush
+    in6 = File.read("/usr/include/#{hdr}")
+    if in6.gsub!(/\*\(const\s+__uint32_t\s+\*\)\(const\s+void\s+\*\)\(&(\(\w+\))->s6_addr\[(\d+)\]\)/) do
+        i, r = $2.to_i.divmod(4)
+        if r.zero?
+          "#$1->__u6_addr.__u6_addr32[#{i}]"
+        else
+          $&
+        end
+      end
+      FileUtils.mkdir_p(File.dirname(hdr))
+      open(hdr, "w") {|f| f.write(in6)}
+      $distcleanfiles << hdr
+      $distcleandirs << File.dirname(hdr)
+      puts "done"
+    else
+      puts "not needed"
+    end
+  end
+  create_makefile("socket")
+end