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-rw-r--r--REORG.TODO/sysdeps/posix/getaddrinfo.c2598
1 files changed, 2598 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/posix/getaddrinfo.c b/REORG.TODO/sysdeps/posix/getaddrinfo.c
new file mode 100644
index 0000000000..a8bdd9a182
--- /dev/null
+++ b/REORG.TODO/sysdeps/posix/getaddrinfo.c
@@ -0,0 +1,2598 @@
+/* Host and service name lookups using Name Service Switch modules.
+   Copyright (C) 1996-2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* The Inner Net License, Version 2.00
+
+  The author(s) grant permission for redistribution and use in source and
+binary forms, with or without modification, of the software and documentation
+provided that the following conditions are met:
+
+0. If you receive a version of the software that is specifically labelled
+   as not being for redistribution (check the version message and/or README),
+   you are not permitted to redistribute that version of the software in any
+   way or form.
+1. All terms of the all other applicable copyrights and licenses must be
+   followed.
+2. Redistributions of source code must retain the authors' copyright
+   notice(s), this list of conditions, and the following disclaimer.
+3. Redistributions in binary form must reproduce the authors' copyright
+   notice(s), this list of conditions, and the following disclaimer in the
+   documentation and/or other materials provided with the distribution.
+4. [The copyright holder has authorized the removal of this clause.]
+5. Neither the name(s) of the author(s) nor the names of its contributors
+   may be used to endorse or promote products derived from this software
+   without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY ITS AUTHORS AND CONTRIBUTORS ``AS IS'' AND ANY
+EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR ANY
+DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+  If these license terms cause you a real problem, contact the author.  */
+
+/* This software is Copyright 1996 by Craig Metz, All Rights Reserved.  */
+
+#include <assert.h>
+#include <ctype.h>
+#include <errno.h>
+#include <ifaddrs.h>
+#include <netdb.h>
+#include <nss.h>
+#include <resolv/resolv-internal.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdio_ext.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+#include <arpa/inet.h>
+#include <net/if.h>
+#include <netinet/in.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/un.h>
+#include <sys/utsname.h>
+#include <unistd.h>
+#include <nsswitch.h>
+#include <libc-lock.h>
+#include <not-cancel.h>
+#include <nscd/nscd-client.h>
+#include <nscd/nscd_proto.h>
+#include <resolv/res_hconf.h>
+#include <scratch_buffer.h>
+#include <inet/net-internal.h>
+
+#ifdef HAVE_LIBIDN
+extern int __idna_to_ascii_lz (const char *input, char **output, int flags);
+extern int __idna_to_unicode_lzlz (const char *input, char **output,
+				   int flags);
+# include <libidn/idna.h>
+#endif
+
+struct gaih_service
+  {
+    const char *name;
+    int num;
+  };
+
+struct gaih_servtuple
+  {
+    struct gaih_servtuple *next;
+    int socktype;
+    int protocol;
+    int port;
+  };
+
+static const struct gaih_servtuple nullserv;
+
+
+struct gaih_typeproto
+  {
+    int socktype;
+    int protocol;
+    uint8_t protoflag;
+    bool defaultflag;
+    char name[8];
+  };
+
+/* Values for `protoflag'.  */
+#define GAI_PROTO_NOSERVICE	1
+#define GAI_PROTO_PROTOANY	2
+
+static const struct gaih_typeproto gaih_inet_typeproto[] =
+{
+  { 0, 0, 0, false, "" },
+  { SOCK_STREAM, IPPROTO_TCP, 0, true, "tcp" },
+  { SOCK_DGRAM, IPPROTO_UDP, 0, true, "udp" },
+#if defined SOCK_DCCP && defined IPPROTO_DCCP
+  { SOCK_DCCP, IPPROTO_DCCP, 0, false, "dccp" },
+#endif
+#ifdef IPPROTO_UDPLITE
+  { SOCK_DGRAM, IPPROTO_UDPLITE, 0, false, "udplite" },
+#endif
+#ifdef IPPROTO_SCTP
+  { SOCK_STREAM, IPPROTO_SCTP, 0, false, "sctp" },
+  { SOCK_SEQPACKET, IPPROTO_SCTP, 0, false, "sctp" },
+#endif
+  { SOCK_RAW, 0, GAI_PROTO_PROTOANY|GAI_PROTO_NOSERVICE, true, "raw" },
+  { 0, 0, 0, false, "" }
+};
+
+static const struct addrinfo default_hints =
+  {
+    .ai_flags = AI_DEFAULT,
+    .ai_family = PF_UNSPEC,
+    .ai_socktype = 0,
+    .ai_protocol = 0,
+    .ai_addrlen = 0,
+    .ai_addr = NULL,
+    .ai_canonname = NULL,
+    .ai_next = NULL
+  };
+
+
+static int
+gaih_inet_serv (const char *servicename, const struct gaih_typeproto *tp,
+		const struct addrinfo *req, struct gaih_servtuple *st,
+		struct scratch_buffer *tmpbuf)
+{
+  struct servent *s;
+  struct servent ts;
+  int r;
+
+  do
+    {
+      r = __getservbyname_r (servicename, tp->name, &ts,
+			     tmpbuf->data, tmpbuf->length, &s);
+      if (r != 0 || s == NULL)
+	{
+	  if (r == ERANGE)
+	    {
+	      if (!scratch_buffer_grow (tmpbuf))
+		return -EAI_MEMORY;
+	    }
+	  else
+	    return -EAI_SERVICE;
+	}
+    }
+  while (r);
+
+  st->next = NULL;
+  st->socktype = tp->socktype;
+  st->protocol = ((tp->protoflag & GAI_PROTO_PROTOANY)
+		  ? req->ai_protocol : tp->protocol);
+  st->port = s->s_port;
+
+  return 0;
+}
+
+/* Convert struct hostent to a list of struct gaih_addrtuple objects.
+   h_name is not copied, and the struct hostent object must not be
+   deallocated prematurely.  *RESULT must be NULL or a pointer to an
+   object allocated using malloc, which is freed.  */
+static bool
+convert_hostent_to_gaih_addrtuple (const struct addrinfo *req,
+				   int family,
+				   struct hostent *h,
+				   struct gaih_addrtuple **result)
+{
+  free (*result);
+  *result = NULL;
+
+  /* Count the number of addresses in h->h_addr_list.  */
+  size_t count = 0;
+  for (char **p = h->h_addr_list; *p != NULL; ++p)
+    ++count;
+
+  /* Report no data if no addresses are available, or if the incoming
+     address size is larger than what we can store.  */
+  if (count == 0 || h->h_length > sizeof (((struct gaih_addrtuple) {}).addr))
+    return true;
+
+  struct gaih_addrtuple *array = calloc (count, sizeof (*array));
+  if (array == NULL)
+    return false;
+
+  for (size_t i = 0; i < count; ++i)
+    {
+      if (family == AF_INET && req->ai_family == AF_INET6)
+	{
+	  /* Perform address mapping. */
+	  array[i].family = AF_INET6;
+	  memcpy(array[i].addr + 3, h->h_addr_list[i], sizeof (uint32_t));
+	  array[i].addr[2] = htonl (0xffff);
+	}
+      else
+	{
+	  array[i].family = family;
+	  memcpy (array[i].addr, h->h_addr_list[i], h->h_length);
+	}
+      array[i].next = array + i + 1;
+    }
+  array[0].name = h->h_name;
+  array[count - 1].next = NULL;
+
+  *result = array;
+  return true;
+}
+
+#define gethosts(_family, _type) \
+ {									      \
+  int herrno;								      \
+  struct hostent th;							      \
+  struct hostent *h;							      \
+  char *localcanon = NULL;						      \
+  no_data = 0;								      \
+  while (1) {								      \
+    rc = 0;								      \
+    status = DL_CALL_FCT (fct, (name, _family, &th,			      \
+				tmpbuf->data, tmpbuf->length,		      \
+				&rc, &herrno, NULL, &localcanon));	      \
+    if (rc != ERANGE || herrno != NETDB_INTERNAL)			      \
+      break;								      \
+    if (!scratch_buffer_grow (tmpbuf))					      \
+      {									      \
+	result = -EAI_MEMORY;						      \
+	goto free_and_return;						      \
+      }									      \
+  }									      \
+  if (status == NSS_STATUS_SUCCESS && rc == 0)				      \
+    h = &th;								      \
+  else									      \
+    h = NULL;								      \
+  if (rc != 0)								      \
+    {									      \
+      if (herrno == NETDB_INTERNAL)					      \
+	{								      \
+	  __set_h_errno (herrno);					      \
+	  _res.options |= old_res_options & DEPRECATED_RES_USE_INET6;	      \
+	  result = -EAI_SYSTEM;						      \
+	  goto free_and_return;						      \
+	}								      \
+      if (herrno == TRY_AGAIN)						      \
+	no_data = EAI_AGAIN;						      \
+      else								      \
+	no_data = herrno == NO_DATA;					      \
+    }									      \
+  else if (h != NULL)							      \
+    {									      \
+      if (!convert_hostent_to_gaih_addrtuple (req, _family,h, &addrmem))      \
+	{								      \
+	  _res.options |= old_res_options & DEPRECATED_RES_USE_INET6;	      \
+	  result = -EAI_SYSTEM;						      \
+	  goto free_and_return;						      \
+	}								      \
+      *pat = addrmem;							      \
+									      \
+      if (localcanon != NULL && canon == NULL)				      \
+	{								      \
+	  canonbuf = __strdup (localcanon);				      \
+	  if (canonbuf == NULL)						      \
+	    {								      \
+	      result = -EAI_SYSTEM;					      \
+	      goto free_and_return;					      \
+	    }								      \
+	  canon = canonbuf;						      \
+	}								      \
+      if (_family == AF_INET6 && *pat != NULL)				      \
+	got_ipv6 = true;						      \
+    }									      \
+ }
+
+
+typedef enum nss_status (*nss_gethostbyname4_r)
+  (const char *name, struct gaih_addrtuple **pat,
+   char *buffer, size_t buflen, int *errnop,
+   int *h_errnop, int32_t *ttlp);
+typedef enum nss_status (*nss_gethostbyname3_r)
+  (const char *name, int af, struct hostent *host,
+   char *buffer, size_t buflen, int *errnop,
+   int *h_errnop, int32_t *ttlp, char **canonp);
+typedef enum nss_status (*nss_getcanonname_r)
+  (const char *name, char *buffer, size_t buflen, char **result,
+   int *errnop, int *h_errnop);
+extern service_user *__nss_hosts_database attribute_hidden;
+
+/* This function is called if a canonical name is requested, but if
+   the service function did not provide it.  It tries to obtain the
+   name using getcanonname_r from the same service NIP.  If the name
+   cannot be canonicalized, return a copy of NAME.  Return NULL on
+   memory allocation failure.  The returned string is allocated on the
+   heap; the caller has to free it.  */
+static char *
+getcanonname (service_user *nip, struct gaih_addrtuple *at, const char *name)
+{
+  nss_getcanonname_r cfct = __nss_lookup_function (nip, "getcanonname_r");
+  char *s = (char *) name;
+  if (cfct != NULL)
+    {
+      char buf[256];
+      int herrno;
+      int rc;
+      if (DL_CALL_FCT (cfct, (at->name ?: name, buf, sizeof (buf),
+			      &s, &rc, &herrno)) != NSS_STATUS_SUCCESS)
+	/* If the canonical name cannot be determined, use the passed
+	   string.  */
+	s = (char *) name;
+    }
+  return __strdup (name);
+}
+
+static int
+gaih_inet (const char *name, const struct gaih_service *service,
+	   const struct addrinfo *req, struct addrinfo **pai,
+	   unsigned int *naddrs, struct scratch_buffer *tmpbuf)
+{
+  const struct gaih_typeproto *tp = gaih_inet_typeproto;
+  struct gaih_servtuple *st = (struct gaih_servtuple *) &nullserv;
+  struct gaih_addrtuple *at = NULL;
+  int rc;
+  bool got_ipv6 = false;
+  const char *canon = NULL;
+  const char *orig_name = name;
+
+  /* Reserve stack memory for the scratch buffer in the getaddrinfo
+     function.  */
+  size_t alloca_used = sizeof (struct scratch_buffer);
+
+  if (req->ai_protocol || req->ai_socktype)
+    {
+      ++tp;
+
+      while (tp->name[0]
+	     && ((req->ai_socktype != 0 && req->ai_socktype != tp->socktype)
+		 || (req->ai_protocol != 0
+		     && !(tp->protoflag & GAI_PROTO_PROTOANY)
+		     && req->ai_protocol != tp->protocol)))
+	++tp;
+
+      if (! tp->name[0])
+	{
+	  if (req->ai_socktype)
+	    return -EAI_SOCKTYPE;
+	  else
+	    return -EAI_SERVICE;
+	}
+    }
+
+  int port = 0;
+  if (service != NULL)
+    {
+      if ((tp->protoflag & GAI_PROTO_NOSERVICE) != 0)
+	return -EAI_SERVICE;
+
+      if (service->num < 0)
+	{
+	  if (tp->name[0])
+	    {
+	      st = (struct gaih_servtuple *)
+		alloca_account (sizeof (struct gaih_servtuple), alloca_used);
+
+	      if ((rc = gaih_inet_serv (service->name, tp, req, st, tmpbuf)))
+		return rc;
+	    }
+	  else
+	    {
+	      struct gaih_servtuple **pst = &st;
+	      for (tp++; tp->name[0]; tp++)
+		{
+		  struct gaih_servtuple *newp;
+
+		  if ((tp->protoflag & GAI_PROTO_NOSERVICE) != 0)
+		    continue;
+
+		  if (req->ai_socktype != 0
+		      && req->ai_socktype != tp->socktype)
+		    continue;
+		  if (req->ai_protocol != 0
+		      && !(tp->protoflag & GAI_PROTO_PROTOANY)
+		      && req->ai_protocol != tp->protocol)
+		    continue;
+
+		  newp = (struct gaih_servtuple *)
+		    alloca_account (sizeof (struct gaih_servtuple),
+				    alloca_used);
+
+		  if ((rc = gaih_inet_serv (service->name,
+					    tp, req, newp, tmpbuf)))
+		    {
+		      if (rc)
+			continue;
+		      return rc;
+		    }
+
+		  *pst = newp;
+		  pst = &(newp->next);
+		}
+	      if (st == (struct gaih_servtuple *) &nullserv)
+		return -EAI_SERVICE;
+	    }
+	}
+      else
+	{
+	  port = htons (service->num);
+	  goto got_port;
+	}
+    }
+  else
+    {
+    got_port:
+
+      if (req->ai_socktype || req->ai_protocol)
+	{
+	  st = alloca_account (sizeof (struct gaih_servtuple), alloca_used);
+	  st->next = NULL;
+	  st->socktype = tp->socktype;
+	  st->protocol = ((tp->protoflag & GAI_PROTO_PROTOANY)
+			  ? req->ai_protocol : tp->protocol);
+	  st->port = port;
+	}
+      else
+	{
+	  /* Neither socket type nor protocol is set.  Return all socket types
+	     we know about.  */
+	  struct gaih_servtuple **lastp = &st;
+	  for (++tp; tp->name[0]; ++tp)
+	    if (tp->defaultflag)
+	      {
+		struct gaih_servtuple *newp;
+
+		newp = alloca_account (sizeof (struct gaih_servtuple),
+				       alloca_used);
+		newp->next = NULL;
+		newp->socktype = tp->socktype;
+		newp->protocol = tp->protocol;
+		newp->port = port;
+
+		*lastp = newp;
+		lastp = &newp->next;
+	      }
+	}
+    }
+
+  bool malloc_name = false;
+  struct gaih_addrtuple *addrmem = NULL;
+  char *canonbuf = NULL;
+  int result = 0;
+
+  if (name != NULL)
+    {
+      at = alloca_account (sizeof (struct gaih_addrtuple), alloca_used);
+      at->family = AF_UNSPEC;
+      at->scopeid = 0;
+      at->next = NULL;
+
+#ifdef HAVE_LIBIDN
+      if (req->ai_flags & AI_IDN)
+	{
+	  int idn_flags = 0;
+	  if (req->ai_flags & AI_IDN_ALLOW_UNASSIGNED)
+	    idn_flags |= IDNA_ALLOW_UNASSIGNED;
+	  if (req->ai_flags & AI_IDN_USE_STD3_ASCII_RULES)
+	    idn_flags |= IDNA_USE_STD3_ASCII_RULES;
+
+	  char *p = NULL;
+	  rc = __idna_to_ascii_lz (name, &p, idn_flags);
+	  if (rc != IDNA_SUCCESS)
+	    {
+	      /* No need to jump to free_and_return here.  */
+	      if (rc == IDNA_MALLOC_ERROR)
+		return -EAI_MEMORY;
+	      if (rc == IDNA_DLOPEN_ERROR)
+		return -EAI_SYSTEM;
+	      return -EAI_IDN_ENCODE;
+	    }
+	  /* In case the output string is the same as the input string
+	     no new string has been allocated.  */
+	  if (p != name)
+	    {
+	      name = p;
+	      malloc_name = true;
+	    }
+	}
+#endif
+
+      if (__inet_aton (name, (struct in_addr *) at->addr) != 0)
+	{
+	  if (req->ai_family == AF_UNSPEC || req->ai_family == AF_INET)
+	    at->family = AF_INET;
+	  else if (req->ai_family == AF_INET6 && (req->ai_flags & AI_V4MAPPED))
+	    {
+	      at->addr[3] = at->addr[0];
+	      at->addr[2] = htonl (0xffff);
+	      at->addr[1] = 0;
+	      at->addr[0] = 0;
+	      at->family = AF_INET6;
+	    }
+	  else
+	    {
+	      result = -EAI_ADDRFAMILY;
+	      goto free_and_return;
+	    }
+
+	  if (req->ai_flags & AI_CANONNAME)
+	    canon = name;
+	}
+      else if (at->family == AF_UNSPEC)
+	{
+	  char *scope_delim = strchr (name, SCOPE_DELIMITER);
+	  int e;
+
+	  {
+	    bool malloc_namebuf = false;
+	    char *namebuf = (char *) name;
+
+	    if (__glibc_unlikely (scope_delim != NULL))
+	      {
+		if (malloc_name)
+		  *scope_delim = '\0';
+		else
+		  {
+		    if (__libc_use_alloca (alloca_used
+					   + scope_delim - name + 1))
+		      {
+			namebuf = alloca_account (scope_delim - name + 1,
+						  alloca_used);
+			*((char *) __mempcpy (namebuf, name,
+					      scope_delim - name)) = '\0';
+		      }
+		    else
+		      {
+			namebuf = __strndup (name, scope_delim - name);
+			if (namebuf == NULL)
+			  {
+			    assert (!malloc_name);
+			    return -EAI_MEMORY;
+			  }
+			malloc_namebuf = true;
+		      }
+		  }
+	      }
+
+	    e = inet_pton (AF_INET6, namebuf, at->addr);
+
+	    if (malloc_namebuf)
+	      free (namebuf);
+	    else if (scope_delim != NULL && malloc_name)
+	      /* Undo what we did above.  */
+	      *scope_delim = SCOPE_DELIMITER;
+	  }
+	  if (e > 0)
+	    {
+	      if (req->ai_family == AF_UNSPEC || req->ai_family == AF_INET6)
+		at->family = AF_INET6;
+	      else if (req->ai_family == AF_INET
+		       && IN6_IS_ADDR_V4MAPPED (at->addr))
+		{
+		  at->addr[0] = at->addr[3];
+		  at->family = AF_INET;
+		}
+	      else
+		{
+		  result = -EAI_ADDRFAMILY;
+		  goto free_and_return;
+		}
+
+	      if (scope_delim != NULL
+		  && __inet6_scopeid_pton ((struct in6_addr *) at->addr,
+					   scope_delim + 1,
+					   &at->scopeid) != 0)
+		{
+		  result = -EAI_NONAME;
+		  goto free_and_return;
+		}
+
+	      if (req->ai_flags & AI_CANONNAME)
+		canon = name;
+	    }
+	}
+
+      if (at->family == AF_UNSPEC && (req->ai_flags & AI_NUMERICHOST) == 0)
+	{
+	  struct gaih_addrtuple **pat = &at;
+	  int no_data = 0;
+	  int no_inet6_data = 0;
+	  service_user *nip;
+	  enum nss_status inet6_status = NSS_STATUS_UNAVAIL;
+	  enum nss_status status = NSS_STATUS_UNAVAIL;
+	  int no_more;
+	  int old_res_options;
+
+	  /* If we do not have to look for IPv6 addresses or the canonical
+	     name, use the simple, old functions, which do not support
+	     IPv6 scope ids, nor retrieving the canonical name.  */
+	  if (req->ai_family == AF_INET
+	      && (req->ai_flags & AI_CANONNAME) == 0)
+	    {
+	      int rc;
+	      struct hostent th;
+	      struct hostent *h;
+	      int herrno;
+
+	      while (1)
+		{
+		  rc = __gethostbyname2_r (name, AF_INET, &th,
+					   tmpbuf->data, tmpbuf->length,
+					   &h, &herrno);
+		  if (rc != ERANGE || herrno != NETDB_INTERNAL)
+		    break;
+		  if (!scratch_buffer_grow (tmpbuf))
+		    {
+		      result = -EAI_MEMORY;
+		      goto free_and_return;
+		    }
+		}
+
+	      if (rc == 0)
+		{
+		  if (h != NULL)
+		    {
+		      /* We found data, convert it.  */
+		      if (!convert_hostent_to_gaih_addrtuple
+			  (req, AF_INET, h, &addrmem))
+			{
+			  result = -EAI_MEMORY;
+			  goto free_and_return;
+			}
+		      *pat = addrmem;
+		    }
+		}
+	      else
+		{
+		  if (herrno == NETDB_INTERNAL)
+		    {
+		      __set_h_errno (herrno);
+		      result = -EAI_SYSTEM;
+		    }
+		  else if (herrno == TRY_AGAIN)
+		    result = -EAI_AGAIN;
+		  else
+		    /* We made requests but they turned out no data.
+		       The name is known, though.  */
+		    result = -EAI_NODATA;
+
+		  goto free_and_return;
+		}
+
+	      goto process_list;
+	    }
+
+#ifdef USE_NSCD
+	  if (__nss_not_use_nscd_hosts > 0
+	      && ++__nss_not_use_nscd_hosts > NSS_NSCD_RETRY)
+	    __nss_not_use_nscd_hosts = 0;
+
+	  if (!__nss_not_use_nscd_hosts
+	      && !__nss_database_custom[NSS_DBSIDX_hosts])
+	    {
+	      /* Try to use nscd.  */
+	      struct nscd_ai_result *air = NULL;
+	      int herrno;
+	      int err = __nscd_getai (name, &air, &herrno);
+	      if (air != NULL)
+		{
+		  /* Transform into gaih_addrtuple list.  */
+		  bool added_canon = (req->ai_flags & AI_CANONNAME) == 0;
+		  char *addrs = air->addrs;
+
+		  addrmem = calloc (air->naddrs, sizeof (*addrmem));
+		  if (addrmem == NULL)
+		    {
+		      result = -EAI_MEMORY;
+		      goto free_and_return;
+		    }
+
+		  struct gaih_addrtuple *addrfree = addrmem;
+		  for (int i = 0; i < air->naddrs; ++i)
+		    {
+		      socklen_t size = (air->family[i] == AF_INET
+					? INADDRSZ : IN6ADDRSZ);
+
+		      if (!((air->family[i] == AF_INET
+			     && req->ai_family == AF_INET6
+			     && (req->ai_flags & AI_V4MAPPED) != 0)
+			    || req->ai_family == AF_UNSPEC
+			    || air->family[i] == req->ai_family))
+			{
+			  /* Skip over non-matching result.  */
+			  addrs += size;
+			  continue;
+			}
+
+		      if (*pat == NULL)
+			{
+			  *pat = addrfree++;
+			  (*pat)->scopeid = 0;
+			}
+		      uint32_t *pataddr = (*pat)->addr;
+		      (*pat)->next = NULL;
+		      if (added_canon || air->canon == NULL)
+			(*pat)->name = NULL;
+		      else if (canonbuf == NULL)
+			{
+			  canonbuf = __strdup (air->canon);
+			  if (canonbuf == NULL)
+			    {
+			      result = -EAI_MEMORY;
+			      goto free_and_return;
+			    }
+			  canon = (*pat)->name = canonbuf;
+			}
+
+		      if (air->family[i] == AF_INET
+			  && req->ai_family == AF_INET6
+			  && (req->ai_flags & AI_V4MAPPED))
+			{
+			  (*pat)->family = AF_INET6;
+			  pataddr[3] = *(uint32_t *) addrs;
+			  pataddr[2] = htonl (0xffff);
+			  pataddr[1] = 0;
+			  pataddr[0] = 0;
+			  pat = &((*pat)->next);
+			  added_canon = true;
+			}
+		      else if (req->ai_family == AF_UNSPEC
+			       || air->family[i] == req->ai_family)
+			{
+			  (*pat)->family = air->family[i];
+			  memcpy (pataddr, addrs, size);
+			  pat = &((*pat)->next);
+			  added_canon = true;
+			  if (air->family[i] == AF_INET6)
+			    got_ipv6 = true;
+			}
+		      addrs += size;
+		    }
+
+		  free (air);
+
+		  if (at->family == AF_UNSPEC)
+		    {
+		      result = -EAI_NONAME;
+		      goto free_and_return;
+		    }
+
+		  goto process_list;
+		}
+	      else if (err == 0)
+		/* The database contains a negative entry.  */
+		goto free_and_return;
+	      else if (__nss_not_use_nscd_hosts == 0)
+		{
+		  if (herrno == NETDB_INTERNAL && errno == ENOMEM)
+		    result = -EAI_MEMORY;
+		  else if (herrno == TRY_AGAIN)
+		    result = -EAI_AGAIN;
+		  else
+		    result = -EAI_SYSTEM;
+
+		  goto free_and_return;
+		}
+	    }
+#endif
+
+	  if (__nss_hosts_database == NULL)
+	    no_more = __nss_database_lookup ("hosts", NULL,
+					     "dns [!UNAVAIL=return] files",
+					     &__nss_hosts_database);
+	  else
+	    no_more = 0;
+	  nip = __nss_hosts_database;
+
+	  /* Initialize configurations.  */
+	  _res_hconf_init ();
+	  if (__res_maybe_init (&_res, 0) == -1)
+	    no_more = 1;
+
+	  /* If we are looking for both IPv4 and IPv6 address we don't
+	     want the lookup functions to automatically promote IPv4
+	     addresses to IPv6 addresses.  Currently this is decided
+	     by setting the RES_USE_INET6 bit in _res.options.  */
+	  old_res_options = _res.options;
+	  _res.options &= ~DEPRECATED_RES_USE_INET6;
+
+	  while (!no_more)
+	    {
+	      no_data = 0;
+	      nss_gethostbyname4_r fct4 = NULL;
+
+	      /* gethostbyname4_r sends out parallel A and AAAA queries and
+		 is thus only suitable for PF_UNSPEC.  */
+	      if (req->ai_family == PF_UNSPEC)
+		fct4 = __nss_lookup_function (nip, "gethostbyname4_r");
+
+	      if (fct4 != NULL)
+		{
+		  int herrno;
+
+		  while (1)
+		    {
+		      rc = 0;
+		      status = DL_CALL_FCT (fct4, (name, pat,
+						   tmpbuf->data, tmpbuf->length,
+						   &rc, &herrno,
+						   NULL));
+		      if (status == NSS_STATUS_SUCCESS)
+			break;
+		      if (status != NSS_STATUS_TRYAGAIN
+			  || rc != ERANGE || herrno != NETDB_INTERNAL)
+			{
+			  if (herrno == TRY_AGAIN)
+			    no_data = EAI_AGAIN;
+			  else
+			    no_data = herrno == NO_DATA;
+			  break;
+			}
+
+		      if (!scratch_buffer_grow (tmpbuf))
+			{
+			  _res.options
+			    |= old_res_options & DEPRECATED_RES_USE_INET6;
+			  result = -EAI_MEMORY;
+			  goto free_and_return;
+			}
+		    }
+
+		  if (status == NSS_STATUS_SUCCESS)
+		    {
+		      assert (!no_data);
+		      no_data = 1;
+
+		      if ((req->ai_flags & AI_CANONNAME) != 0 && canon == NULL)
+			canon = (*pat)->name;
+
+		      while (*pat != NULL)
+			{
+			  if ((*pat)->family == AF_INET
+			      && req->ai_family == AF_INET6
+			      && (req->ai_flags & AI_V4MAPPED) != 0)
+			    {
+			      uint32_t *pataddr = (*pat)->addr;
+			      (*pat)->family = AF_INET6;
+			      pataddr[3] = pataddr[0];
+			      pataddr[2] = htonl (0xffff);
+			      pataddr[1] = 0;
+			      pataddr[0] = 0;
+			      pat = &((*pat)->next);
+			      no_data = 0;
+			    }
+			  else if (req->ai_family == AF_UNSPEC
+				   || (*pat)->family == req->ai_family)
+			    {
+			      pat = &((*pat)->next);
+
+			      no_data = 0;
+			      if (req->ai_family == AF_INET6)
+				got_ipv6 = true;
+			    }
+			  else
+			    *pat = ((*pat)->next);
+			}
+		    }
+
+		  no_inet6_data = no_data;
+		}
+	      else
+		{
+		  nss_gethostbyname3_r fct = NULL;
+		  if (req->ai_flags & AI_CANONNAME)
+		    /* No need to use this function if we do not look for
+		       the canonical name.  The function does not exist in
+		       all NSS modules and therefore the lookup would
+		       often fail.  */
+		    fct = __nss_lookup_function (nip, "gethostbyname3_r");
+		  if (fct == NULL)
+		    /* We are cheating here.  The gethostbyname2_r
+		       function does not have the same interface as
+		       gethostbyname3_r but the extra arguments the
+		       latter takes are added at the end.  So the
+		       gethostbyname2_r code will just ignore them.  */
+		    fct = __nss_lookup_function (nip, "gethostbyname2_r");
+
+		  if (fct != NULL)
+		    {
+		      if (req->ai_family == AF_INET6
+			  || req->ai_family == AF_UNSPEC)
+			{
+			  gethosts (AF_INET6, struct in6_addr);
+			  no_inet6_data = no_data;
+			  inet6_status = status;
+			}
+		      if (req->ai_family == AF_INET
+			  || req->ai_family == AF_UNSPEC
+			  || (req->ai_family == AF_INET6
+			      && (req->ai_flags & AI_V4MAPPED)
+			      /* Avoid generating the mapped addresses if we
+				 know we are not going to need them.  */
+			      && ((req->ai_flags & AI_ALL) || !got_ipv6)))
+			{
+			  gethosts (AF_INET, struct in_addr);
+
+			  if (req->ai_family == AF_INET)
+			    {
+			      no_inet6_data = no_data;
+			      inet6_status = status;
+			    }
+			}
+
+		      /* If we found one address for AF_INET or AF_INET6,
+			 don't continue the search.  */
+		      if (inet6_status == NSS_STATUS_SUCCESS
+			  || status == NSS_STATUS_SUCCESS)
+			{
+			  if ((req->ai_flags & AI_CANONNAME) != 0
+			      && canon == NULL)
+			    {
+			      canonbuf = getcanonname (nip, at, name);
+			      if (canonbuf == NULL)
+				{
+				  _res.options
+				    |= old_res_options
+				    & DEPRECATED_RES_USE_INET6;
+				  result = -EAI_MEMORY;
+				  goto free_and_return;
+				}
+			      canon = canonbuf;
+			    }
+			  status = NSS_STATUS_SUCCESS;
+			}
+		      else
+			{
+			  /* We can have different states for AF_INET and
+			     AF_INET6.  Try to find a useful one for both.  */
+			  if (inet6_status == NSS_STATUS_TRYAGAIN)
+			    status = NSS_STATUS_TRYAGAIN;
+			  else if (status == NSS_STATUS_UNAVAIL
+				   && inet6_status != NSS_STATUS_UNAVAIL)
+			    status = inet6_status;
+			}
+		    }
+		  else
+		    {
+		      status = NSS_STATUS_UNAVAIL;
+		      /* Could not load any of the lookup functions.  Indicate
+		         an internal error if the failure was due to a system
+			 error other than the file not being found.  We use the
+			 errno from the last failed callback.  */
+		      if (errno != 0 && errno != ENOENT)
+			__set_h_errno (NETDB_INTERNAL);
+		    }
+		}
+
+	      if (nss_next_action (nip, status) == NSS_ACTION_RETURN)
+		break;
+
+	      if (nip->next == NULL)
+		no_more = -1;
+	      else
+		nip = nip->next;
+	    }
+
+	  _res.options |= old_res_options & DEPRECATED_RES_USE_INET6;
+
+	  if (h_errno == NETDB_INTERNAL)
+	    {
+	      result = -EAI_SYSTEM;
+	      goto free_and_return;
+	    }
+
+	  if (no_data != 0 && no_inet6_data != 0)
+	    {
+	      /* If both requests timed out report this.  */
+	      if (no_data == EAI_AGAIN && no_inet6_data == EAI_AGAIN)
+		result = -EAI_AGAIN;
+	      else
+		/* We made requests but they turned out no data.  The name
+		   is known, though.  */
+		result = -EAI_NODATA;
+
+	      goto free_and_return;
+	    }
+	}
+
+    process_list:
+      if (at->family == AF_UNSPEC)
+	{
+	  result = -EAI_NONAME;
+	  goto free_and_return;
+	}
+    }
+  else
+    {
+      struct gaih_addrtuple *atr;
+      atr = at = alloca_account (sizeof (struct gaih_addrtuple), alloca_used);
+      memset (at, '\0', sizeof (struct gaih_addrtuple));
+
+      if (req->ai_family == AF_UNSPEC)
+	{
+	  at->next = __alloca (sizeof (struct gaih_addrtuple));
+	  memset (at->next, '\0', sizeof (struct gaih_addrtuple));
+	}
+
+      if (req->ai_family == AF_UNSPEC || req->ai_family == AF_INET6)
+	{
+	  at->family = AF_INET6;
+	  if ((req->ai_flags & AI_PASSIVE) == 0)
+	    memcpy (at->addr, &in6addr_loopback, sizeof (struct in6_addr));
+	  atr = at->next;
+	}
+
+      if (req->ai_family == AF_UNSPEC || req->ai_family == AF_INET)
+	{
+	  atr->family = AF_INET;
+	  if ((req->ai_flags & AI_PASSIVE) == 0)
+	    atr->addr[0] = htonl (INADDR_LOOPBACK);
+	}
+    }
+
+  {
+    struct gaih_servtuple *st2;
+    struct gaih_addrtuple *at2 = at;
+    size_t socklen;
+    sa_family_t family;
+
+    /*
+      buffer is the size of an unformatted IPv6 address in printable format.
+     */
+    while (at2 != NULL)
+      {
+	/* Only the first entry gets the canonical name.  */
+	if (at2 == at && (req->ai_flags & AI_CANONNAME) != 0)
+	  {
+	    if (canon == NULL)
+	      /* If the canonical name cannot be determined, use
+		 the passed in string.  */
+	      canon = orig_name;
+
+#ifdef HAVE_LIBIDN
+	    if (req->ai_flags & AI_CANONIDN)
+	      {
+		int idn_flags = 0;
+		if (req->ai_flags & AI_IDN_ALLOW_UNASSIGNED)
+		  idn_flags |= IDNA_ALLOW_UNASSIGNED;
+		if (req->ai_flags & AI_IDN_USE_STD3_ASCII_RULES)
+		  idn_flags |= IDNA_USE_STD3_ASCII_RULES;
+
+		char *out;
+		int rc = __idna_to_unicode_lzlz (canon, &out, idn_flags);
+		if (rc != IDNA_SUCCESS)
+		  {
+		    if (rc == IDNA_MALLOC_ERROR)
+		      result = -EAI_MEMORY;
+		    else if (rc == IDNA_DLOPEN_ERROR)
+		      result = -EAI_SYSTEM;
+		    else
+		      result = -EAI_IDN_ENCODE;
+		    goto free_and_return;
+		  }
+		/* In case the output string is the same as the input
+		   string no new string has been allocated and we
+		   make a copy.  */
+		if (out == canon)
+		  goto make_copy;
+		canon = out;
+	      }
+	    else
+#endif
+	      {
+#ifdef HAVE_LIBIDN
+	      make_copy:
+#endif
+		if (canonbuf != NULL)
+		  /* We already allocated the string using malloc, but
+		     the buffer is now owned by canon.  */
+		  canonbuf = NULL;
+		else
+		  {
+		    canon = __strdup (canon);
+		    if (canon == NULL)
+		      {
+			result = -EAI_MEMORY;
+			goto free_and_return;
+		      }
+		  }
+	      }
+	  }
+
+	family = at2->family;
+	if (family == AF_INET6)
+	  {
+	    socklen = sizeof (struct sockaddr_in6);
+
+	    /* If we looked up IPv4 mapped address discard them here if
+	       the caller isn't interested in all address and we have
+	       found at least one IPv6 address.  */
+	    if (got_ipv6
+		&& (req->ai_flags & (AI_V4MAPPED|AI_ALL)) == AI_V4MAPPED
+		&& IN6_IS_ADDR_V4MAPPED (at2->addr))
+	      goto ignore;
+	  }
+	else
+	  socklen = sizeof (struct sockaddr_in);
+
+	for (st2 = st; st2 != NULL; st2 = st2->next)
+	  {
+	    struct addrinfo *ai;
+	    ai = *pai = malloc (sizeof (struct addrinfo) + socklen);
+	    if (ai == NULL)
+	      {
+		free ((char *) canon);
+		result = -EAI_MEMORY;
+		goto free_and_return;
+	      }
+
+	    ai->ai_flags = req->ai_flags;
+	    ai->ai_family = family;
+	    ai->ai_socktype = st2->socktype;
+	    ai->ai_protocol = st2->protocol;
+	    ai->ai_addrlen = socklen;
+	    ai->ai_addr = (void *) (ai + 1);
+
+	    /* We only add the canonical name once.  */
+	    ai->ai_canonname = (char *) canon;
+	    canon = NULL;
+
+#ifdef _HAVE_SA_LEN
+	    ai->ai_addr->sa_len = socklen;
+#endif /* _HAVE_SA_LEN */
+	    ai->ai_addr->sa_family = family;
+
+	    /* In case of an allocation error the list must be NULL
+	       terminated.  */
+	    ai->ai_next = NULL;
+
+	    if (family == AF_INET6)
+	      {
+		struct sockaddr_in6 *sin6p =
+		  (struct sockaddr_in6 *) ai->ai_addr;
+
+		sin6p->sin6_port = st2->port;
+		sin6p->sin6_flowinfo = 0;
+		memcpy (&sin6p->sin6_addr,
+			at2->addr, sizeof (struct in6_addr));
+		sin6p->sin6_scope_id = at2->scopeid;
+	      }
+	    else
+	      {
+		struct sockaddr_in *sinp =
+		  (struct sockaddr_in *) ai->ai_addr;
+		sinp->sin_port = st2->port;
+		memcpy (&sinp->sin_addr,
+			at2->addr, sizeof (struct in_addr));
+		memset (sinp->sin_zero, '\0', sizeof (sinp->sin_zero));
+	      }
+
+	    pai = &(ai->ai_next);
+	  }
+
+	++*naddrs;
+
+      ignore:
+	at2 = at2->next;
+      }
+  }
+
+ free_and_return:
+  if (malloc_name)
+    free ((char *) name);
+  free (addrmem);
+  free (canonbuf);
+
+  return result;
+}
+
+
+struct sort_result
+{
+  struct addrinfo *dest_addr;
+  /* Using sockaddr_storage is for now overkill.  We only support IPv4
+     and IPv6 so far.  If this changes at some point we can adjust the
+     type here.  */
+  struct sockaddr_in6 source_addr;
+  uint8_t source_addr_len;
+  bool got_source_addr;
+  uint8_t source_addr_flags;
+  uint8_t prefixlen;
+  uint32_t index;
+  int32_t native;
+};
+
+struct sort_result_combo
+{
+  struct sort_result *results;
+  int nresults;
+};
+
+
+#if __BYTE_ORDER == __BIG_ENDIAN
+# define htonl_c(n) n
+#else
+# define htonl_c(n) __bswap_constant_32 (n)
+#endif
+
+static const struct scopeentry
+{
+  union
+  {
+    char addr[4];
+    uint32_t addr32;
+  };
+  uint32_t netmask;
+  int32_t scope;
+} default_scopes[] =
+  {
+    /* Link-local addresses: scope 2.  */
+    { { { 169, 254, 0, 0 } }, htonl_c (0xffff0000), 2 },
+    { { { 127, 0, 0, 0 } }, htonl_c (0xff000000), 2 },
+    /* Default: scope 14.  */
+    { { { 0, 0, 0, 0 } }, htonl_c (0x00000000), 14 }
+  };
+
+/* The label table.  */
+static const struct scopeentry *scopes;
+
+
+static int
+get_scope (const struct sockaddr_in6 *in6)
+{
+  int scope;
+  if (in6->sin6_family == PF_INET6)
+    {
+      if (! IN6_IS_ADDR_MULTICAST (&in6->sin6_addr))
+	{
+	  if (IN6_IS_ADDR_LINKLOCAL (&in6->sin6_addr)
+	      /* RFC 4291 2.5.3 says that the loopback address is to be
+		 treated like a link-local address.  */
+	      || IN6_IS_ADDR_LOOPBACK (&in6->sin6_addr))
+	    scope = 2;
+	  else if (IN6_IS_ADDR_SITELOCAL (&in6->sin6_addr))
+	    scope = 5;
+	  else
+	    /* XXX Is this the correct default behavior?  */
+	    scope = 14;
+	}
+      else
+	scope = in6->sin6_addr.s6_addr[1] & 0xf;
+    }
+  else if (in6->sin6_family == PF_INET)
+    {
+      const struct sockaddr_in *in = (const struct sockaddr_in *) in6;
+
+      size_t cnt = 0;
+      while (1)
+	{
+	  if ((in->sin_addr.s_addr & scopes[cnt].netmask)
+	      == scopes[cnt].addr32)
+	    return scopes[cnt].scope;
+
+	  ++cnt;
+	}
+      /* NOTREACHED */
+    }
+  else
+    /* XXX What is a good default?  */
+    scope = 15;
+
+  return scope;
+}
+
+
+struct prefixentry
+{
+  struct in6_addr prefix;
+  unsigned int bits;
+  int val;
+};
+
+
+/* The label table.  */
+static const struct prefixentry *labels;
+
+/* Default labels.  */
+static const struct prefixentry default_labels[] =
+  {
+    /* See RFC 3484 for the details.  */
+    { { .__in6_u
+	= { .__u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01 } }
+      }, 128, 0 },
+    { { .__in6_u
+	= { .__u6_addr8 = { 0x20, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } }
+      }, 16, 2 },
+    { { .__in6_u
+	= { .__u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } }
+      }, 96, 3 },
+    { { .__in6_u
+	= { .__u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			    0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00 } }
+      }, 96, 4 },
+    /* The next two entries differ from RFC 3484.  We need to treat
+       IPv6 site-local addresses special because they are never NATed,
+       unlike site-locale IPv4 addresses.  If this would not happen, on
+       machines which have only IPv4 and IPv6 site-local addresses, the
+       sorting would prefer the IPv6 site-local addresses, causing
+       unnecessary delays when trying to connect to a global IPv6 address
+       through a site-local IPv6 address.  */
+    { { .__in6_u
+	= { .__u6_addr8 = { 0xfe, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } }
+      }, 10, 5 },
+    { { .__in6_u
+	= { .__u6_addr8 = { 0xfc, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } }
+      }, 7, 6 },
+    /* Additional rule for Teredo tunnels.  */
+    { { .__in6_u
+	= { .__u6_addr8 = { 0x20, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } }
+      }, 32, 7 },
+    { { .__in6_u
+	= { .__u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } }
+      }, 0, 1 }
+  };
+
+
+/* The precedence table.  */
+static const struct prefixentry *precedence;
+
+/* The default precedences.  */
+static const struct prefixentry default_precedence[] =
+  {
+    /* See RFC 3484 for the details.  */
+    { { .__in6_u
+	= { .__u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01 } }
+      }, 128, 50 },
+    { { .__in6_u
+	= { .__u6_addr8 = { 0x20, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } }
+      }, 16, 30 },
+    { { .__in6_u
+	= { .__u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } }
+      }, 96, 20 },
+    { { .__in6_u
+	= { .__u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			    0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00 } }
+      }, 96, 10 },
+    { { .__in6_u
+	= { .__u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } }
+      }, 0, 40 }
+  };
+
+
+static int
+match_prefix (const struct sockaddr_in6 *in6,
+	      const struct prefixentry *list, int default_val)
+{
+  int idx;
+  struct sockaddr_in6 in6_mem;
+
+  if (in6->sin6_family == PF_INET)
+    {
+      const struct sockaddr_in *in = (const struct sockaddr_in *) in6;
+
+      /* Construct a V4-to-6 mapped address.  */
+      in6_mem.sin6_family = PF_INET6;
+      in6_mem.sin6_port = in->sin_port;
+      in6_mem.sin6_flowinfo = 0;
+      memset (&in6_mem.sin6_addr, '\0', sizeof (in6_mem.sin6_addr));
+      in6_mem.sin6_addr.s6_addr16[5] = 0xffff;
+      in6_mem.sin6_addr.s6_addr32[3] = in->sin_addr.s_addr;
+      in6_mem.sin6_scope_id = 0;
+
+      in6 = &in6_mem;
+    }
+  else if (in6->sin6_family != PF_INET6)
+    return default_val;
+
+  for (idx = 0; ; ++idx)
+    {
+      unsigned int bits = list[idx].bits;
+      const uint8_t *mask = list[idx].prefix.s6_addr;
+      const uint8_t *val = in6->sin6_addr.s6_addr;
+
+      while (bits >= 8)
+	{
+	  if (*mask != *val)
+	    break;
+
+	  ++mask;
+	  ++val;
+	  bits -= 8;
+	}
+
+      if (bits < 8)
+	{
+	  if ((*mask & (0xff00 >> bits)) == (*val & (0xff00 >> bits)))
+	    /* Match!  */
+	    break;
+	}
+    }
+
+  return list[idx].val;
+}
+
+
+static int
+get_label (const struct sockaddr_in6 *in6)
+{
+  /* XXX What is a good default value?  */
+  return match_prefix (in6, labels, INT_MAX);
+}
+
+
+static int
+get_precedence (const struct sockaddr_in6 *in6)
+{
+  /* XXX What is a good default value?  */
+  return match_prefix (in6, precedence, 0);
+}
+
+
+/* Find last bit set in a word.  */
+static int
+fls (uint32_t a)
+{
+  uint32_t mask;
+  int n;
+  for (n = 0, mask = 1 << 31; n < 32; mask >>= 1, ++n)
+    if ((a & mask) != 0)
+      break;
+  return n;
+}
+
+
+static int
+rfc3484_sort (const void *p1, const void *p2, void *arg)
+{
+  const size_t idx1 = *(const size_t *) p1;
+  const size_t idx2 = *(const size_t *) p2;
+  struct sort_result_combo *src = (struct sort_result_combo *) arg;
+  struct sort_result *a1 = &src->results[idx1];
+  struct sort_result *a2 = &src->results[idx2];
+
+  /* Rule 1: Avoid unusable destinations.
+     We have the got_source_addr flag set if the destination is reachable.  */
+  if (a1->got_source_addr && ! a2->got_source_addr)
+    return -1;
+  if (! a1->got_source_addr && a2->got_source_addr)
+    return 1;
+
+
+  /* Rule 2: Prefer matching scope.  Only interesting if both
+     destination addresses are IPv6.  */
+  int a1_dst_scope
+    = get_scope ((struct sockaddr_in6 *) a1->dest_addr->ai_addr);
+
+  int a2_dst_scope
+    = get_scope ((struct sockaddr_in6 *) a2->dest_addr->ai_addr);
+
+  if (a1->got_source_addr)
+    {
+      int a1_src_scope = get_scope (&a1->source_addr);
+      int a2_src_scope = get_scope (&a2->source_addr);
+
+      if (a1_dst_scope == a1_src_scope && a2_dst_scope != a2_src_scope)
+	return -1;
+      if (a1_dst_scope != a1_src_scope && a2_dst_scope == a2_src_scope)
+	return 1;
+    }
+
+
+  /* Rule 3: Avoid deprecated addresses.  */
+  if (a1->got_source_addr)
+    {
+      if (!(a1->source_addr_flags & in6ai_deprecated)
+	  && (a2->source_addr_flags & in6ai_deprecated))
+	return -1;
+      if ((a1->source_addr_flags & in6ai_deprecated)
+	  && !(a2->source_addr_flags & in6ai_deprecated))
+	return 1;
+    }
+
+  /* Rule 4: Prefer home addresses.  */
+  if (a1->got_source_addr)
+    {
+      if (!(a1->source_addr_flags & in6ai_homeaddress)
+	  && (a2->source_addr_flags & in6ai_homeaddress))
+	return 1;
+      if ((a1->source_addr_flags & in6ai_homeaddress)
+	  && !(a2->source_addr_flags & in6ai_homeaddress))
+	return -1;
+    }
+
+  /* Rule 5: Prefer matching label.  */
+  if (a1->got_source_addr)
+    {
+      int a1_dst_label
+	= get_label ((struct sockaddr_in6 *) a1->dest_addr->ai_addr);
+      int a1_src_label = get_label (&a1->source_addr);
+
+      int a2_dst_label
+	= get_label ((struct sockaddr_in6 *) a2->dest_addr->ai_addr);
+      int a2_src_label = get_label (&a2->source_addr);
+
+      if (a1_dst_label == a1_src_label && a2_dst_label != a2_src_label)
+	return -1;
+      if (a1_dst_label != a1_src_label && a2_dst_label == a2_src_label)
+	return 1;
+    }
+
+
+  /* Rule 6: Prefer higher precedence.  */
+  int a1_prec
+    = get_precedence ((struct sockaddr_in6 *) a1->dest_addr->ai_addr);
+  int a2_prec
+    = get_precedence ((struct sockaddr_in6 *) a2->dest_addr->ai_addr);
+
+  if (a1_prec > a2_prec)
+    return -1;
+  if (a1_prec < a2_prec)
+    return 1;
+
+
+  /* Rule 7: Prefer native transport.  */
+  if (a1->got_source_addr)
+    {
+      /* The same interface index means the same interface which means
+	 there is no difference in transport.  This should catch many
+	 (most?) cases.  */
+      if (a1->index != a2->index)
+	{
+	  int a1_native = a1->native;
+	  int a2_native = a2->native;
+
+	  if (a1_native == -1 || a2_native == -1)
+	    {
+	      uint32_t a1_index;
+	      if (a1_native == -1)
+		{
+		  /* If we do not have the information use 'native' as
+		     the default.  */
+		  a1_native = 0;
+		  a1_index = a1->index;
+		}
+	      else
+		a1_index = 0xffffffffu;
+
+	      uint32_t a2_index;
+	      if (a2_native == -1)
+		{
+		  /* If we do not have the information use 'native' as
+		     the default.  */
+		  a2_native = 0;
+		  a2_index = a2->index;
+		}
+	      else
+		a2_index = 0xffffffffu;
+
+	      __check_native (a1_index, &a1_native, a2_index, &a2_native);
+
+	      /* Fill in the results in all the records.  */
+	      for (int i = 0; i < src->nresults; ++i)
+		if (a1_index != -1 && src->results[i].index == a1_index)
+		  {
+		    assert (src->results[i].native == -1
+			    || src->results[i].native == a1_native);
+		    src->results[i].native = a1_native;
+		  }
+		else if (a2_index != -1 && src->results[i].index == a2_index)
+		  {
+		    assert (src->results[i].native == -1
+			    || src->results[i].native == a2_native);
+		    src->results[i].native = a2_native;
+		  }
+	    }
+
+	  if (a1_native && !a2_native)
+	    return -1;
+	  if (!a1_native && a2_native)
+	    return 1;
+	}
+    }
+
+
+  /* Rule 8: Prefer smaller scope.  */
+  if (a1_dst_scope < a2_dst_scope)
+    return -1;
+  if (a1_dst_scope > a2_dst_scope)
+    return 1;
+
+
+  /* Rule 9: Use longest matching prefix.  */
+  if (a1->got_source_addr
+      && a1->dest_addr->ai_family == a2->dest_addr->ai_family)
+    {
+      int bit1 = 0;
+      int bit2 = 0;
+
+      if (a1->dest_addr->ai_family == PF_INET)
+	{
+	  assert (a1->source_addr.sin6_family == PF_INET);
+	  assert (a2->source_addr.sin6_family == PF_INET);
+
+	  /* Outside of subnets, as defined by the network masks,
+	     common address prefixes for IPv4 addresses make no sense.
+	     So, define a non-zero value only if source and
+	     destination address are on the same subnet.  */
+	  struct sockaddr_in *in1_dst
+	    = (struct sockaddr_in *) a1->dest_addr->ai_addr;
+	  in_addr_t in1_dst_addr = ntohl (in1_dst->sin_addr.s_addr);
+	  struct sockaddr_in *in1_src
+	    = (struct sockaddr_in *) &a1->source_addr;
+	  in_addr_t in1_src_addr = ntohl (in1_src->sin_addr.s_addr);
+	  in_addr_t netmask1 = 0xffffffffu << (32 - a1->prefixlen);
+
+	  if ((in1_src_addr & netmask1) == (in1_dst_addr & netmask1))
+	    bit1 = fls (in1_dst_addr ^ in1_src_addr);
+
+	  struct sockaddr_in *in2_dst
+	    = (struct sockaddr_in *) a2->dest_addr->ai_addr;
+	  in_addr_t in2_dst_addr = ntohl (in2_dst->sin_addr.s_addr);
+	  struct sockaddr_in *in2_src
+	    = (struct sockaddr_in *) &a2->source_addr;
+	  in_addr_t in2_src_addr = ntohl (in2_src->sin_addr.s_addr);
+	  in_addr_t netmask2 = 0xffffffffu << (32 - a2->prefixlen);
+
+	  if ((in2_src_addr & netmask2) == (in2_dst_addr & netmask2))
+	    bit2 = fls (in2_dst_addr ^ in2_src_addr);
+	}
+      else if (a1->dest_addr->ai_family == PF_INET6)
+	{
+	  assert (a1->source_addr.sin6_family == PF_INET6);
+	  assert (a2->source_addr.sin6_family == PF_INET6);
+
+	  struct sockaddr_in6 *in1_dst;
+	  struct sockaddr_in6 *in1_src;
+	  struct sockaddr_in6 *in2_dst;
+	  struct sockaddr_in6 *in2_src;
+
+	  in1_dst = (struct sockaddr_in6 *) a1->dest_addr->ai_addr;
+	  in1_src = (struct sockaddr_in6 *) &a1->source_addr;
+	  in2_dst = (struct sockaddr_in6 *) a2->dest_addr->ai_addr;
+	  in2_src = (struct sockaddr_in6 *) &a2->source_addr;
+
+	  int i;
+	  for (i = 0; i < 4; ++i)
+	    if (in1_dst->sin6_addr.s6_addr32[i]
+		!= in1_src->sin6_addr.s6_addr32[i]
+		|| (in2_dst->sin6_addr.s6_addr32[i]
+		    != in2_src->sin6_addr.s6_addr32[i]))
+	      break;
+
+	  if (i < 4)
+	    {
+	      bit1 = fls (ntohl (in1_dst->sin6_addr.s6_addr32[i]
+				 ^ in1_src->sin6_addr.s6_addr32[i]));
+	      bit2 = fls (ntohl (in2_dst->sin6_addr.s6_addr32[i]
+				 ^ in2_src->sin6_addr.s6_addr32[i]));
+	    }
+	}
+
+      if (bit1 > bit2)
+	return -1;
+      if (bit1 < bit2)
+	return 1;
+    }
+
+
+  /* Rule 10: Otherwise, leave the order unchanged.  To ensure this
+     compare with the value indicating the order in which the entries
+     have been received from the services.  NB: no two entries can have
+     the same order so the test will never return zero.  */
+  return idx1 < idx2 ? -1 : 1;
+}
+
+
+static int
+in6aicmp (const void *p1, const void *p2)
+{
+  struct in6addrinfo *a1 = (struct in6addrinfo *) p1;
+  struct in6addrinfo *a2 = (struct in6addrinfo *) p2;
+
+  return memcmp (a1->addr, a2->addr, sizeof (a1->addr));
+}
+
+
+/* Name of the config file for RFC 3484 sorting (for now).  */
+#define GAICONF_FNAME "/etc/gai.conf"
+
+
+/* Non-zero if we are supposed to reload the config file automatically
+   whenever it changed.  */
+static int gaiconf_reload_flag;
+
+/* Non-zero if gaiconf_reload_flag was ever set to true.  */
+static int gaiconf_reload_flag_ever_set;
+
+/* Last modification time.  */
+#ifdef _STATBUF_ST_NSEC
+
+static struct timespec gaiconf_mtime;
+
+static inline void
+save_gaiconf_mtime (const struct stat64 *st)
+{
+  gaiconf_mtime = st->st_mtim;
+}
+
+static inline bool
+check_gaiconf_mtime (const struct stat64 *st)
+{
+  return (st->st_mtim.tv_sec == gaiconf_mtime.tv_sec
+          && st->st_mtim.tv_nsec == gaiconf_mtime.tv_nsec);
+}
+
+#else
+
+static time_t gaiconf_mtime;
+
+static inline void
+save_gaiconf_mtime (const struct stat64 *st)
+{
+  gaiconf_mtime = st->st_mtime;
+}
+
+static inline bool
+check_gaiconf_mtime (const struct stat64 *st)
+{
+  return st->st_mtime == gaiconf_mtime;
+}
+
+#endif
+
+
+libc_freeres_fn(fini)
+{
+  if (labels != default_labels)
+    {
+      const struct prefixentry *old = labels;
+      labels = default_labels;
+      free ((void *) old);
+    }
+
+  if (precedence != default_precedence)
+    {
+      const struct prefixentry *old = precedence;
+      precedence = default_precedence;
+      free ((void *) old);
+    }
+
+  if (scopes != default_scopes)
+    {
+      const struct scopeentry *old = scopes;
+      scopes = default_scopes;
+      free ((void *) old);
+    }
+}
+
+
+struct prefixlist
+{
+  struct prefixentry entry;
+  struct prefixlist *next;
+};
+
+
+struct scopelist
+{
+  struct scopeentry entry;
+  struct scopelist *next;
+};
+
+
+static void
+free_prefixlist (struct prefixlist *list)
+{
+  while (list != NULL)
+    {
+      struct prefixlist *oldp = list;
+      list = list->next;
+      free (oldp);
+    }
+}
+
+
+static void
+free_scopelist (struct scopelist *list)
+{
+  while (list != NULL)
+    {
+      struct scopelist *oldp = list;
+      list = list->next;
+      free (oldp);
+    }
+}
+
+
+static int
+prefixcmp (const void *p1, const void *p2)
+{
+  const struct prefixentry *e1 = (const struct prefixentry *) p1;
+  const struct prefixentry *e2 = (const struct prefixentry *) p2;
+
+  if (e1->bits < e2->bits)
+    return 1;
+  if (e1->bits == e2->bits)
+    return 0;
+  return -1;
+}
+
+
+static int
+scopecmp (const void *p1, const void *p2)
+{
+  const struct scopeentry *e1 = (const struct scopeentry *) p1;
+  const struct scopeentry *e2 = (const struct scopeentry *) p2;
+
+  if (e1->netmask > e2->netmask)
+    return -1;
+  if (e1->netmask == e2->netmask)
+    return 0;
+  return 1;
+}
+
+
+static void
+gaiconf_init (void)
+{
+  struct prefixlist *labellist = NULL;
+  size_t nlabellist = 0;
+  bool labellist_nullbits = false;
+  struct prefixlist *precedencelist = NULL;
+  size_t nprecedencelist = 0;
+  bool precedencelist_nullbits = false;
+  struct scopelist *scopelist =  NULL;
+  size_t nscopelist = 0;
+  bool scopelist_nullbits = false;
+
+  FILE *fp = fopen (GAICONF_FNAME, "rce");
+  if (fp != NULL)
+    {
+      struct stat64 st;
+      if (__fxstat64 (_STAT_VER, fileno (fp), &st) != 0)
+	{
+	  fclose (fp);
+	  goto no_file;
+	}
+
+      char *line = NULL;
+      size_t linelen = 0;
+
+      __fsetlocking (fp, FSETLOCKING_BYCALLER);
+
+      while (!feof_unlocked (fp))
+	{
+	  ssize_t n = __getline (&line, &linelen, fp);
+	  if (n <= 0)
+	    break;
+
+	  /* Handle comments.  No escaping possible so this is easy.  */
+	  char *cp = strchr (line, '#');
+	  if (cp != NULL)
+	    *cp = '\0';
+
+	  cp = line;
+	  while (isspace (*cp))
+	    ++cp;
+
+	  char *cmd = cp;
+	  while (*cp != '\0' && !isspace (*cp))
+	    ++cp;
+	  size_t cmdlen = cp - cmd;
+
+	  if (*cp != '\0')
+	    *cp++ = '\0';
+	  while (isspace (*cp))
+	    ++cp;
+
+	  char *val1 = cp;
+	  while (*cp != '\0' && !isspace (*cp))
+	    ++cp;
+	  size_t val1len = cp - cmd;
+
+	  /* We always need at least two values.  */
+	  if (val1len == 0)
+	    continue;
+
+	  if (*cp != '\0')
+	    *cp++ = '\0';
+	  while (isspace (*cp))
+	    ++cp;
+
+	  char *val2 = cp;
+	  while (*cp != '\0' && !isspace (*cp))
+	    ++cp;
+
+	  /*  Ignore the rest of the line.  */
+	  *cp = '\0';
+
+	  struct prefixlist **listp;
+	  size_t *lenp;
+	  bool *nullbitsp;
+	  switch (cmdlen)
+	    {
+	    case 5:
+	      if (strcmp (cmd, "label") == 0)
+		{
+		  struct in6_addr prefix;
+		  unsigned long int bits;
+		  unsigned long int val;
+		  char *endp;
+
+		  listp = &labellist;
+		  lenp = &nlabellist;
+		  nullbitsp = &labellist_nullbits;
+
+		new_elem:
+		  bits = 128;
+		  __set_errno (0);
+		  cp = strchr (val1, '/');
+		  if (cp != NULL)
+		    *cp++ = '\0';
+		  if (inet_pton (AF_INET6, val1, &prefix)
+		      && (cp == NULL
+			  || (bits = strtoul (cp, &endp, 10)) != ULONG_MAX
+			  || errno != ERANGE)
+		      && *endp == '\0'
+		      && bits <= 128
+		      && ((val = strtoul (val2, &endp, 10)) != ULONG_MAX
+			  || errno != ERANGE)
+		      && *endp == '\0'
+		      && val <= INT_MAX)
+		    {
+		      struct prefixlist *newp = malloc (sizeof (*newp));
+		      if (newp == NULL)
+			{
+			  free (line);
+			  fclose (fp);
+			  goto no_file;
+			}
+
+		      memcpy (&newp->entry.prefix, &prefix, sizeof (prefix));
+		      newp->entry.bits = bits;
+		      newp->entry.val = val;
+		      newp->next = *listp;
+		      *listp = newp;
+		      ++*lenp;
+		      *nullbitsp |= bits == 0;
+		    }
+		}
+	      break;
+
+	    case 6:
+	      if (strcmp (cmd, "reload") == 0)
+		{
+		  gaiconf_reload_flag = strcmp (val1, "yes") == 0;
+		  if (gaiconf_reload_flag)
+		    gaiconf_reload_flag_ever_set = 1;
+		}
+	      break;
+
+	    case 7:
+	      if (strcmp (cmd, "scopev4") == 0)
+		{
+		  struct in6_addr prefix;
+		  unsigned long int bits;
+		  unsigned long int val;
+		  char *endp;
+
+		  bits = 32;
+		  __set_errno (0);
+		  cp = strchr (val1, '/');
+		  if (cp != NULL)
+		    *cp++ = '\0';
+		  if (inet_pton (AF_INET6, val1, &prefix))
+		    {
+		      bits = 128;
+		      if (IN6_IS_ADDR_V4MAPPED (&prefix)
+			  && (cp == NULL
+			      || (bits = strtoul (cp, &endp, 10)) != ULONG_MAX
+			      || errno != ERANGE)
+			  && *endp == '\0'
+			  && bits >= 96
+			  && bits <= 128
+			  && ((val = strtoul (val2, &endp, 10)) != ULONG_MAX
+			      || errno != ERANGE)
+			  && *endp == '\0'
+			  && val <= INT_MAX)
+			{
+			  struct scopelist *newp;
+			new_scope:
+			  newp = malloc (sizeof (*newp));
+			  if (newp == NULL)
+			    {
+			      free (line);
+			      fclose (fp);
+			      goto no_file;
+			    }
+
+			  newp->entry.netmask = htonl (bits != 96
+						       ? (0xffffffff
+							  << (128 - bits))
+						       : 0);
+			  newp->entry.addr32 = (prefix.s6_addr32[3]
+						& newp->entry.netmask);
+			  newp->entry.scope = val;
+			  newp->next = scopelist;
+			  scopelist = newp;
+			  ++nscopelist;
+			  scopelist_nullbits |= bits == 96;
+			}
+		    }
+		  else if (inet_pton (AF_INET, val1, &prefix.s6_addr32[3])
+			   && (cp == NULL
+			       || (bits = strtoul (cp, &endp, 10)) != ULONG_MAX
+			       || errno != ERANGE)
+			   && *endp == '\0'
+			   && bits <= 32
+			   && ((val = strtoul (val2, &endp, 10)) != ULONG_MAX
+			       || errno != ERANGE)
+			   && *endp == '\0'
+			   && val <= INT_MAX)
+		    {
+		      bits += 96;
+		      goto new_scope;
+		    }
+		}
+	      break;
+
+	    case 10:
+	      if (strcmp (cmd, "precedence") == 0)
+		{
+		  listp = &precedencelist;
+		  lenp = &nprecedencelist;
+		  nullbitsp = &precedencelist_nullbits;
+		  goto new_elem;
+		}
+	      break;
+	    }
+	}
+
+      free (line);
+
+      fclose (fp);
+
+      /* Create the array for the labels.  */
+      struct prefixentry *new_labels;
+      if (nlabellist > 0)
+	{
+	  if (!labellist_nullbits)
+	    ++nlabellist;
+	  new_labels = malloc (nlabellist * sizeof (*new_labels));
+	  if (new_labels == NULL)
+	    goto no_file;
+
+	  int i = nlabellist;
+	  if (!labellist_nullbits)
+	    {
+	      --i;
+	      memset (&new_labels[i].prefix, '\0', sizeof (struct in6_addr));
+	      new_labels[i].bits = 0;
+	      new_labels[i].val = 1;
+	    }
+
+	  struct prefixlist *l = labellist;
+	  while (i-- > 0)
+	    {
+	      new_labels[i] = l->entry;
+	      l = l->next;
+	    }
+	  free_prefixlist (labellist);
+
+	  /* Sort the entries so that the most specific ones are at
+	     the beginning.  */
+	  qsort (new_labels, nlabellist, sizeof (*new_labels), prefixcmp);
+	}
+      else
+	new_labels = (struct prefixentry *) default_labels;
+
+      struct prefixentry *new_precedence;
+      if (nprecedencelist > 0)
+	{
+	  if (!precedencelist_nullbits)
+	    ++nprecedencelist;
+	  new_precedence = malloc (nprecedencelist * sizeof (*new_precedence));
+	  if (new_precedence == NULL)
+	    {
+	      if (new_labels != default_labels)
+		free (new_labels);
+	      goto no_file;
+	    }
+
+	  int i = nprecedencelist;
+	  if (!precedencelist_nullbits)
+	    {
+	      --i;
+	      memset (&new_precedence[i].prefix, '\0',
+		      sizeof (struct in6_addr));
+	      new_precedence[i].bits = 0;
+	      new_precedence[i].val = 40;
+	    }
+
+	  struct prefixlist *l = precedencelist;
+	  while (i-- > 0)
+	    {
+	      new_precedence[i] = l->entry;
+	      l = l->next;
+	    }
+	  free_prefixlist (precedencelist);
+
+	  /* Sort the entries so that the most specific ones are at
+	     the beginning.  */
+	  qsort (new_precedence, nprecedencelist, sizeof (*new_precedence),
+		 prefixcmp);
+	}
+      else
+	new_precedence = (struct prefixentry *) default_precedence;
+
+      struct scopeentry *new_scopes;
+      if (nscopelist > 0)
+	{
+	  if (!scopelist_nullbits)
+	    ++nscopelist;
+	  new_scopes = malloc (nscopelist * sizeof (*new_scopes));
+	  if (new_scopes == NULL)
+	    {
+	      if (new_labels != default_labels)
+		free (new_labels);
+	      if (new_precedence != default_precedence)
+		free (new_precedence);
+	      goto no_file;
+	    }
+
+	  int i = nscopelist;
+	  if (!scopelist_nullbits)
+	    {
+	      --i;
+	      new_scopes[i].addr32 = 0;
+	      new_scopes[i].netmask = 0;
+	      new_scopes[i].scope = 14;
+	    }
+
+	  struct scopelist *l = scopelist;
+	  while (i-- > 0)
+	    {
+	      new_scopes[i] = l->entry;
+	      l = l->next;
+	    }
+	  free_scopelist (scopelist);
+
+	  /* Sort the entries so that the most specific ones are at
+	     the beginning.  */
+	  qsort (new_scopes, nscopelist, sizeof (*new_scopes),
+		 scopecmp);
+	}
+      else
+	new_scopes = (struct scopeentry *) default_scopes;
+
+      /* Now we are ready to replace the values.  */
+      const struct prefixentry *old = labels;
+      labels = new_labels;
+      if (old != default_labels)
+	free ((void *) old);
+
+      old = precedence;
+      precedence = new_precedence;
+      if (old != default_precedence)
+	free ((void *) old);
+
+      const struct scopeentry *oldscope = scopes;
+      scopes = new_scopes;
+      if (oldscope != default_scopes)
+	free ((void *) oldscope);
+
+      save_gaiconf_mtime (&st);
+    }
+  else
+    {
+    no_file:
+      free_prefixlist (labellist);
+      free_prefixlist (precedencelist);
+      free_scopelist (scopelist);
+
+      /* If we previously read the file but it is gone now, free the
+	 old data and use the builtin one.  Leave the reload flag
+	 alone.  */
+      fini ();
+    }
+}
+
+
+static void
+gaiconf_reload (void)
+{
+  struct stat64 st;
+  if (__xstat64 (_STAT_VER, GAICONF_FNAME, &st) != 0
+      || !check_gaiconf_mtime (&st))
+    gaiconf_init ();
+}
+
+
+int
+getaddrinfo (const char *name, const char *service,
+	     const struct addrinfo *hints, struct addrinfo **pai)
+{
+  int i = 0, last_i = 0;
+  int nresults = 0;
+  struct addrinfo *p = NULL;
+  struct gaih_service gaih_service, *pservice;
+  struct addrinfo local_hints;
+
+  if (name != NULL && name[0] == '*' && name[1] == 0)
+    name = NULL;
+
+  if (service != NULL && service[0] == '*' && service[1] == 0)
+    service = NULL;
+
+  if (name == NULL && service == NULL)
+    return EAI_NONAME;
+
+  if (hints == NULL)
+    hints = &default_hints;
+
+  if (hints->ai_flags
+      & ~(AI_PASSIVE|AI_CANONNAME|AI_NUMERICHOST|AI_ADDRCONFIG|AI_V4MAPPED
+#ifdef HAVE_LIBIDN
+	  |AI_IDN|AI_CANONIDN|AI_IDN_ALLOW_UNASSIGNED
+	  |AI_IDN_USE_STD3_ASCII_RULES
+#endif
+	  |AI_NUMERICSERV|AI_ALL))
+    return EAI_BADFLAGS;
+
+  if ((hints->ai_flags & AI_CANONNAME) && name == NULL)
+    return EAI_BADFLAGS;
+
+  struct in6addrinfo *in6ai = NULL;
+  size_t in6ailen = 0;
+  bool seen_ipv4 = false;
+  bool seen_ipv6 = false;
+  bool check_pf_called = false;
+
+  if (hints->ai_flags & AI_ADDRCONFIG)
+    {
+      /* We might need information about what interfaces are available.
+	 Also determine whether we have IPv4 or IPv6 interfaces or both.  We
+	 cannot cache the results since new interfaces could be added at
+	 any time.  */
+      __check_pf (&seen_ipv4, &seen_ipv6, &in6ai, &in6ailen);
+      check_pf_called = true;
+
+      /* Now make a decision on what we return, if anything.  */
+      if (hints->ai_family == PF_UNSPEC && (seen_ipv4 || seen_ipv6))
+	{
+	  /* If we haven't seen both IPv4 and IPv6 interfaces we can
+	     narrow down the search.  */
+	  if ((! seen_ipv4 || ! seen_ipv6) && (seen_ipv4 || seen_ipv6))
+	    {
+	      local_hints = *hints;
+	      local_hints.ai_family = seen_ipv4 ? PF_INET : PF_INET6;
+	      hints = &local_hints;
+	    }
+	}
+      else if ((hints->ai_family == PF_INET && ! seen_ipv4)
+	       || (hints->ai_family == PF_INET6 && ! seen_ipv6))
+	{
+	  /* We cannot possibly return a valid answer.  */
+	  __free_in6ai (in6ai);
+	  return EAI_NONAME;
+	}
+    }
+
+  if (service && service[0])
+    {
+      char *c;
+      gaih_service.name = service;
+      gaih_service.num = strtoul (gaih_service.name, &c, 10);
+      if (*c != '\0')
+	{
+	  if (hints->ai_flags & AI_NUMERICSERV)
+	    {
+	      __free_in6ai (in6ai);
+	      return EAI_NONAME;
+	    }
+
+	  gaih_service.num = -1;
+	}
+
+      pservice = &gaih_service;
+    }
+  else
+    pservice = NULL;
+
+  struct addrinfo **end = &p;
+
+  unsigned int naddrs = 0;
+  if (hints->ai_family == AF_UNSPEC || hints->ai_family == AF_INET
+      || hints->ai_family == AF_INET6)
+    {
+      struct scratch_buffer tmpbuf;
+      scratch_buffer_init (&tmpbuf);
+      last_i = gaih_inet (name, pservice, hints, end, &naddrs, &tmpbuf);
+      scratch_buffer_free (&tmpbuf);
+
+      if (last_i != 0)
+	{
+	  freeaddrinfo (p);
+	  __free_in6ai (in6ai);
+
+	  return -last_i;
+	}
+      while (*end)
+	{
+	  end = &((*end)->ai_next);
+	  ++nresults;
+	}
+    }
+  else
+    {
+      __free_in6ai (in6ai);
+      return EAI_FAMILY;
+    }
+
+  if (naddrs > 1)
+    {
+      /* Read the config file.  */
+      __libc_once_define (static, once);
+      __typeof (once) old_once = once;
+      __libc_once (once, gaiconf_init);
+      /* Sort results according to RFC 3484.  */
+      struct sort_result *results;
+      size_t *order;
+      struct addrinfo *q;
+      struct addrinfo *last = NULL;
+      char *canonname = NULL;
+      bool malloc_results;
+      size_t alloc_size = nresults * (sizeof (*results) + sizeof (size_t));
+
+      malloc_results
+	= !__libc_use_alloca (alloc_size);
+      if (malloc_results)
+	{
+	  results = malloc (alloc_size);
+	  if (results == NULL)
+	    {
+	      __free_in6ai (in6ai);
+	      return EAI_MEMORY;
+	    }
+	}
+      else
+	results = alloca (alloc_size);
+      order = (size_t *) (results + nresults);
+
+      /* Now we definitely need the interface information.  */
+      if (! check_pf_called)
+	__check_pf (&seen_ipv4, &seen_ipv6, &in6ai, &in6ailen);
+
+      /* If we have information about deprecated and temporary addresses
+	 sort the array now.  */
+      if (in6ai != NULL)
+	qsort (in6ai, in6ailen, sizeof (*in6ai), in6aicmp);
+
+      int fd = -1;
+      int af = AF_UNSPEC;
+
+      for (i = 0, q = p; q != NULL; ++i, last = q, q = q->ai_next)
+	{
+	  results[i].dest_addr = q;
+	  results[i].native = -1;
+	  order[i] = i;
+
+	  /* If we just looked up the address for a different
+	     protocol, reuse the result.  */
+	  if (last != NULL && last->ai_addrlen == q->ai_addrlen
+	      && memcmp (last->ai_addr, q->ai_addr, q->ai_addrlen) == 0)
+	    {
+	      memcpy (&results[i].source_addr, &results[i - 1].source_addr,
+		      results[i - 1].source_addr_len);
+	      results[i].source_addr_len = results[i - 1].source_addr_len;
+	      results[i].got_source_addr = results[i - 1].got_source_addr;
+	      results[i].source_addr_flags = results[i - 1].source_addr_flags;
+	      results[i].prefixlen = results[i - 1].prefixlen;
+	      results[i].index = results[i - 1].index;
+	    }
+	  else
+	    {
+	      results[i].got_source_addr = false;
+	      results[i].source_addr_flags = 0;
+	      results[i].prefixlen = 0;
+	      results[i].index = 0xffffffffu;
+
+	      /* We overwrite the type with SOCK_DGRAM since we do not
+		 want connect() to connect to the other side.  If we
+		 cannot determine the source address remember this
+		 fact.  */
+	      if (fd == -1 || (af == AF_INET && q->ai_family == AF_INET6))
+		{
+		  if (fd != -1)
+		  close_retry:
+		    close_not_cancel_no_status (fd);
+		  af = q->ai_family;
+		  fd = __socket (af, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_IP);
+		}
+	      else
+		{
+		  /* Reset the connection.  */
+		  struct sockaddr sa = { .sa_family = AF_UNSPEC };
+		  __connect (fd, &sa, sizeof (sa));
+		}
+
+	      socklen_t sl = sizeof (results[i].source_addr);
+	      if (fd != -1
+		  && __connect (fd, q->ai_addr, q->ai_addrlen) == 0
+		  && __getsockname (fd,
+				    (struct sockaddr *) &results[i].source_addr,
+				    &sl) == 0)
+		{
+		  results[i].source_addr_len = sl;
+		  results[i].got_source_addr = true;
+
+		  if (in6ai != NULL)
+		    {
+		      /* See whether the source address is on the list of
+			 deprecated or temporary addresses.  */
+		      struct in6addrinfo tmp;
+
+		      if (q->ai_family == AF_INET && af == AF_INET)
+			{
+			  struct sockaddr_in *sinp
+			    = (struct sockaddr_in *) &results[i].source_addr;
+			  tmp.addr[0] = 0;
+			  tmp.addr[1] = 0;
+			  tmp.addr[2] = htonl (0xffff);
+			  /* Special case for lo interface, the source address
+			     being possibly different than the interface
+			     address. */
+			  if ((ntohl(sinp->sin_addr.s_addr) & 0xff000000)
+			      == 0x7f000000)
+			    tmp.addr[3] = htonl(0x7f000001);
+			  else
+			    tmp.addr[3] = sinp->sin_addr.s_addr;
+			}
+		      else
+			{
+			  struct sockaddr_in6 *sin6p
+			    = (struct sockaddr_in6 *) &results[i].source_addr;
+			  memcpy (tmp.addr, &sin6p->sin6_addr, IN6ADDRSZ);
+			}
+
+		      struct in6addrinfo *found
+			= bsearch (&tmp, in6ai, in6ailen, sizeof (*in6ai),
+				   in6aicmp);
+		      if (found != NULL)
+			{
+			  results[i].source_addr_flags = found->flags;
+			  results[i].prefixlen = found->prefixlen;
+			  results[i].index = found->index;
+			}
+		    }
+
+		  if (q->ai_family == AF_INET && af == AF_INET6)
+		    {
+		      /* We have to convert the address.  The socket is
+			 IPv6 and the request is for IPv4.  */
+		      struct sockaddr_in6 *sin6
+			= (struct sockaddr_in6 *) &results[i].source_addr;
+		      struct sockaddr_in *sin
+			= (struct sockaddr_in *) &results[i].source_addr;
+		      assert (IN6_IS_ADDR_V4MAPPED (sin6->sin6_addr.s6_addr32));
+		      sin->sin_family = AF_INET;
+		      /* We do not have to initialize sin_port since this
+			 fields has the same position and size in the IPv6
+			 structure.  */
+		      assert (offsetof (struct sockaddr_in, sin_port)
+			      == offsetof (struct sockaddr_in6, sin6_port));
+		      assert (sizeof (sin->sin_port)
+			      == sizeof (sin6->sin6_port));
+		      memcpy (&sin->sin_addr,
+			      &sin6->sin6_addr.s6_addr32[3], INADDRSZ);
+		      results[i].source_addr_len = sizeof (struct sockaddr_in);
+		    }
+		}
+	      else if (errno == EAFNOSUPPORT && af == AF_INET6
+		       && q->ai_family == AF_INET)
+		/* This could mean IPv6 sockets are IPv6-only.  */
+		goto close_retry;
+	      else
+		/* Just make sure that if we have to process the same
+		   address again we do not copy any memory.  */
+		results[i].source_addr_len = 0;
+	    }
+
+	  /* Remember the canonical name.  */
+	  if (q->ai_canonname != NULL)
+	    {
+	      assert (canonname == NULL);
+	      canonname = q->ai_canonname;
+	      q->ai_canonname = NULL;
+	    }
+	}
+
+      if (fd != -1)
+	close_not_cancel_no_status (fd);
+
+      /* We got all the source addresses we can get, now sort using
+	 the information.  */
+      struct sort_result_combo src
+	= { .results = results, .nresults = nresults };
+      if (__glibc_unlikely (gaiconf_reload_flag_ever_set))
+	{
+	  __libc_lock_define_initialized (static, lock);
+
+	  __libc_lock_lock (lock);
+	  if (__libc_once_get (old_once) && gaiconf_reload_flag)
+	    gaiconf_reload ();
+	  __qsort_r (order, nresults, sizeof (order[0]), rfc3484_sort, &src);
+	  __libc_lock_unlock (lock);
+	}
+      else
+	__qsort_r (order, nresults, sizeof (order[0]), rfc3484_sort, &src);
+
+      /* Queue the results up as they come out of sorting.  */
+      q = p = results[order[0]].dest_addr;
+      for (i = 1; i < nresults; ++i)
+	q = q->ai_next = results[order[i]].dest_addr;
+      q->ai_next = NULL;
+
+      /* Fill in the canonical name into the new first entry.  */
+      p->ai_canonname = canonname;
+
+      if (malloc_results)
+	free (results);
+    }
+
+  __free_in6ai (in6ai);
+
+  if (p)
+    {
+      *pai = p;
+      return 0;
+    }
+
+  return last_i ? -last_i : EAI_NONAME;
+}
+libc_hidden_def (getaddrinfo)
+
+nss_interface_function (getaddrinfo)
+
+void
+freeaddrinfo (struct addrinfo *ai)
+{
+  struct addrinfo *p;
+
+  while (ai != NULL)
+    {
+      p = ai;
+      ai = ai->ai_next;
+      free (p->ai_canonname);
+      free (p);
+    }
+}
+libc_hidden_def (freeaddrinfo)