* include/resolv.h: Adjust __libc_res_nquery and __libc_res_nsend

	prototypes.
	* include/arpa/nameser_compat.h: Define T_UNSPEC.
	* nis/Versions (libnss_nis): Export _nss_nis_gethostbyname4_r.
	(libnss_nisplus): Export _nss_nisplus_gethostbyname4_r.
	* nis/nss_nis/nis-hosts.c (LINE_PARSER): Change to also handle
	af==AF_UNSPEC.
	(_nss_nis_gethostbyname4_r): New function.
	* nis/nss_nisplus/nisplus-hosts.c (_nss_nisplus_parse_hostent):
	Change to also handle af==AF_UNSPEC.
	(get_tablename): New function.  Use it to avoid duplication.
	(_nss_nisplus_gethostbyname4_r): New function.
	* nscd/aicache.c (addhstaiX): Use gethostbyname4_r function is
	available.
	* nss/Versions (libnss_files): Export _nss_files_gethostbyname4_r.
	* nss/nss.h: Define struct gaih_addrtuple.
	* nss/nss_files/files-hosts.c (LINE_PARSER): Change to also handle
	af==AF_UNSPEC.
	(_nss_files_gethostbyname4_r): New function.
	* resolv/Versions (libnss_dns): Export _nss_dns_gethostbyname4_r.
	* resolv/gethnmaddr.c: Adjust __libc_res_nsearch and __libc_res_nquery
	calls.
	* resolv/res_query.c (__libc_res_nquery): Take two additional
	parameters for second answer buffer.  Handle type=T_UNSPEC to mean
	look up IPv4 and IPv6.
	Change all callers.
	* resolv/res_send.c (__libc_res_nsend): Take five aditional parameters
	for an additional query and answer buffer.  Pass to send_vc and
	send_dg.
	(send_vc): Send possibly two requests and receive two answers.
	(send_dg): Likewise.
	* resolv/nss_dns/dns-host.c: Adjust calls to __libc_res_nsearch and
	__libc_res_nquery.
	(_nss_dns_gethostbyname4_r): New function.
	(gaih_getanswer_slice): Likewise.
	(gaih_getanswer): Likewise.
	* resolv/nss_dns/dns-canon.c (_nss_dns_getcanonname_r): Adjust
	__libc_res_nquery call.
	* resolv/nss_dns/dns-network.c (_nss_dns_getnetbyaddr_r): Likewise.
	(_nss_dns_getnetbyname_r): Adjust __libc_res_nsearch call.
	* sysdeps/posix/getaddrinfo.c: Use gethostbyname4_r function is
	available.

17 files changed, 1542 insertions, 504 deletions

diff --git a/ChangeLog b/ChangeLog
index cbeb1596c7..c20a02dfa5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,48 @@
+2008-05-10  Ulrich Drepper  <drepper@redhat.com>
+
+	* include/resolv.h: Adjust __libc_res_nquery and __libc_res_nsend
+	prototypes.
+	* include/arpa/nameser_compat.h: Define T_UNSPEC.
+	* nis/Versions (libnss_nis): Export _nss_nis_gethostbyname4_r.
+	(libnss_nisplus): Export _nss_nisplus_gethostbyname4_r.
+	* nis/nss_nis/nis-hosts.c (LINE_PARSER): Change to also handle
+	af==AF_UNSPEC.
+	(_nss_nis_gethostbyname4_r): New function.
+	* nis/nss_nisplus/nisplus-hosts.c (_nss_nisplus_parse_hostent):
+	Change to also handle af==AF_UNSPEC.
+	(get_tablename): New function.  Use it to avoid duplication.
+	(_nss_nisplus_gethostbyname4_r): New function.
+	* nscd/aicache.c (addhstaiX): Use gethostbyname4_r function is
+	available.
+	* nss/Versions (libnss_files): Export _nss_files_gethostbyname4_r.
+	* nss/nss.h: Define struct gaih_addrtuple.
+	* nss/nss_files/files-hosts.c (LINE_PARSER): Change to also handle
+	af==AF_UNSPEC.
+	(_nss_files_gethostbyname4_r): New function.
+	* resolv/Versions (libnss_dns): Export _nss_dns_gethostbyname4_r.
+	* resolv/gethnmaddr.c: Adjust __libc_res_nsearch and __libc_res_nquery
+	calls.
+	* resolv/res_query.c (__libc_res_nquery): Take two additional
+	parameters for second answer buffer.  Handle type=T_UNSPEC to mean
+	look up IPv4 and IPv6.
+	Change all callers.
+	* resolv/res_send.c (__libc_res_nsend): Take five aditional parameters
+	for an additional query and answer buffer.  Pass to send_vc and
+	send_dg.
+	(send_vc): Send possibly two requests and receive two answers.
+	(send_dg): Likewise.
+	* resolv/nss_dns/dns-host.c: Adjust calls to __libc_res_nsearch and
+	__libc_res_nquery.
+	(_nss_dns_gethostbyname4_r): New function.
+	(gaih_getanswer_slice): Likewise.
+	(gaih_getanswer): Likewise.
+	* resolv/nss_dns/dns-canon.c (_nss_dns_getcanonname_r): Adjust
+	__libc_res_nquery call.
+	* resolv/nss_dns/dns-network.c (_nss_dns_getnetbyaddr_r): Likewise.
+	(_nss_dns_getnetbyname_r): Adjust __libc_res_nsearch call.
+	* sysdeps/posix/getaddrinfo.c: Use gethostbyname4_r function is
+	available.
+
 2008-05-05  David S. Miller  <davem@davemloft.net>
 
 	* sysdeps/sparc/sparc32/Makefile: Use -mcpu=v7 for initfini.s build.
diff --git a/include/arpa/nameser_compat.h b/include/arpa/nameser_compat.h
index bfbb2de58c..2e735ede4c 100644
--- a/include/arpa/nameser_compat.h
+++ b/include/arpa/nameser_compat.h
@@ -1 +1,8 @@
+#ifndef _ARPA_NAMESER_COMPAT_
 #include <resolv/arpa/nameser_compat.h>
+
+/* Picksome unused number to represent lookups of IPv4 and IPv6 (i.e.,
+   T_A and T_AAAA).  */
+#define T_UNSPEC 62321
+
+#endif
diff --git a/nis/Versions b/nis/Versions
index be4453e285..ef9a512417 100644
--- a/nis/Versions
+++ b/nis/Versions
@@ -95,7 +95,7 @@ libnss_nis {
     _nss_nis_setgrent; _nss_nis_sethostent; _nss_nis_setnetent;
     _nss_nis_setnetgrent; _nss_nis_setprotoent; _nss_nis_setpwent;
     _nss_nis_setrpcent; _nss_nis_setservent; _nss_nis_setspent;
-    _nss_nis_initgroups_dyn;
+    _nss_nis_initgroups_dyn; _nss_nis_gethostbyname4_r;
   }
 }
 
@@ -126,5 +126,6 @@ libnss_nisplus {
     _nss_nisplus_setnetent; _nss_nisplus_setnetgrent; _nss_nisplus_setprotoent;
     _nss_nisplus_setpwent; _nss_nisplus_setrpcent; _nss_nisplus_setservent;
     _nss_nisplus_setspent; _nss_nisplus_initgroups_dyn;
+    _nss_nisplus_gethostbyname4_r;
   }
 }
diff --git a/nis/nss_nis/nis-hosts.c b/nis/nss_nis/nis-hosts.c
index 7bf4af786d..24d13634d7 100644
--- a/nis/nss_nis/nis-hosts.c
+++ b/nis/nss_nis/nis-hosts.c
@@ -1,4 +1,5 @@
-/* Copyright (C) 1996-2000, 2002, 2003, 2006, 2007 Free Software Foundation, Inc.
+/* Copyright (C) 1996-2000, 2002, 2003, 2006, 2007, 2008
+   Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Thorsten Kukuk <kukuk@suse.de>, 1996.
 
@@ -17,6 +18,7 @@
    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
    02111-1307 USA.  */
 
+#include <assert.h>
 #include <nss.h>
 #include <ctype.h>
 /* The following is an ugly trick to avoid a prototype declaration for
@@ -61,9 +63,12 @@ LINE_PARSER
 
    STRING_FIELD (addr, isspace, 1);
 
+   assert (af == AF_INET || af == AF_INET6 || af == AF_UNSPEC);
+
    /* Parse address.  */
-   if (af == AF_INET && inet_pton (AF_INET, addr, entdata->host_addr) > 0)
+   if (af != AF_INET6 && inet_pton (AF_INET, addr, entdata->host_addr) > 0)
      {
+       assert ((flags & AI_V4MAPPED) == 0 || af != AF_UNSPEC);
        if (flags & AI_V4MAPPED)
          {
            map_v4v6_address ((char *) entdata->host_addr,
@@ -77,7 +82,7 @@ LINE_PARSER
            result->h_length = INADDRSZ;
          }
      }
-   else if (af == AF_INET6
+   else if (af != AF_INET
             && inet_pton (AF_INET6, addr, entdata->host_addr) > 0)
      {
        result->h_addrtype = AF_INET6;
@@ -102,6 +107,7 @@ static bool_t new_start = 1;
 static char *oldkey = NULL;
 static int oldkeylen = 0;
 
+
 enum nss_status
 _nss_nis_sethostent (int stayopen)
 {
@@ -124,6 +130,7 @@ _nss_nis_sethostent (int stayopen)
    is used so this makes no difference.  */
 strong_alias (_nss_nis_sethostent, _nss_nis_endhostent)
 
+
 /* The calling function always need to get a lock first. */
 static enum nss_status
 internal_nis_gethostent_r (struct hostent *host, char *buffer,
@@ -216,6 +223,7 @@ internal_nis_gethostent_r (struct hostent *host, char *buffer,
   return NSS_STATUS_SUCCESS;
 }
 
+
 enum nss_status
 _nss_nis_gethostent_r (struct hostent *host, char *buffer, size_t buflen,
 		       int *errnop, int *h_errnop)
@@ -233,6 +241,7 @@ _nss_nis_gethostent_r (struct hostent *host, char *buffer, size_t buflen,
   return status;
 }
 
+
 static enum nss_status
 internal_gethostbyname2_r (const char *name, int af, struct hostent *host,
 			   char *buffer, size_t buflen, int *errnop,
@@ -323,16 +332,24 @@ internal_gethostbyname2_r (const char *name, int af, struct hostent *host,
   return NSS_STATUS_SUCCESS;
 }
 
+
 enum nss_status
 _nss_nis_gethostbyname2_r (const char *name, int af, struct hostent *host,
 			   char *buffer, size_t buflen, int *errnop,
 			   int *h_errnop)
 {
+  if (af != AF_INET && af != AF_INET6)
+    {
+      *h_errnop = HOST_NOT_FOUND;
+      return NSS_STATUS_NOTFOUND;
+    }
+
   return internal_gethostbyname2_r (name, af, host, buffer, buflen, errnop,
 				    h_errnop,
 		        ((_res.options & RES_USE_INET6) ? AI_V4MAPPED : 0));
 }
 
+
 enum nss_status
 _nss_nis_gethostbyname_r (const char *name, struct hostent *host, char *buffer,
 			  size_t buflen, int *errnop, int *h_errnop)
@@ -351,6 +368,7 @@ _nss_nis_gethostbyname_r (const char *name, struct hostent *host, char *buffer,
 				    errnop, h_errnop, 0);
 }
 
+
 enum nss_status
 _nss_nis_gethostbyaddr_r (const void *addr, socklen_t addrlen, int af,
 			  struct hostent *host, char *buffer, size_t buflen,
@@ -430,13 +448,93 @@ _nss_nis_gethostbyaddr_r (const void *addr, socklen_t addrlen, int af,
   return NSS_STATUS_SUCCESS;
 }
 
-#if 0
+
 enum nss_status
-_nss_nis_getipnodebyname_r (const char *name, int af, int flags,
-			    struct hostent *result, char *buffer,
-			    size_t buflen, int *errnop, int *herrnop)
+_nss_nis_gethostbyname4_r (const char *name, struct gaih_addrtuple **pat,
+			   char *buffer, size_t buflen, int *errnop,
+			   int *herrnop, int32_t *ttlp)
 {
-  return internal_gethostbyname2_r (name, af, result, buffer, buflen,
-				    errnop, herrnop, flags);
+  char *domain;
+  if (yp_get_default_domain (&domain))
+    return NSS_STATUS_UNAVAIL;
+
+  /* Convert name to lowercase.  */
+  size_t namlen = strlen (name);
+  char name2[namlen + 1];
+  size_t i;
+
+  for (i = 0; i < namlen; ++i)
+    name2[i] = tolower (name[i]);
+  name2[i] = '\0';
+
+  char *result;
+  int len;
+  int yperr = yp_match (domain, "hosts.byname", name2, namlen, &result, &len);
+
+  if (__builtin_expect (yperr != YPERR_SUCCESS, 0))
+    {
+      enum nss_status retval = yperr2nss (yperr);
+
+      if (retval == NSS_STATUS_TRYAGAIN)
+	{
+	  *herrnop = TRY_AGAIN;
+	  *errnop = errno;
+	}
+      if (retval == NSS_STATUS_NOTFOUND)
+	*herrnop = HOST_NOT_FOUND;
+      return retval;
+    }
+
+  struct parser_data data;
+  struct hostent host;
+  int parse_res = parse_line (result, &host, &data, buflen, errnop, AF_UNSPEC,
+			      0);
+  if (__builtin_expect (parse_res < 1, 0))
+    {
+      if (parse_res == -1)
+	{
+	  *herrnop = NETDB_INTERNAL;
+	  return NSS_STATUS_TRYAGAIN;
+	}
+      else
+	{
+	  *herrnop = HOST_NOT_FOUND;
+	  return NSS_STATUS_NOTFOUND;
+	}
+    }
+
+  if (*pat == NULL)
+    {
+      uintptr_t pad = (-(uintptr_t) buffer
+		       % __alignof__ (struct gaih_addrtuple));
+      buffer += pad;
+      buflen = buflen > pad ? buflen - pad : 0;
+
+      if (__builtin_expect (buflen < sizeof (struct gaih_addrtuple), 0))
+	{
+	erange:
+	  free (result);
+	  *errnop = ERANGE;
+	  *herrnop = NETDB_INTERNAL;
+	  return NSS_STATUS_TRYAGAIN;
+	}
+
+      *pat = (struct gaih_addrtuple *) buffer;
+      buffer += sizeof (struct gaih_addrtuple);
+      buflen -= sizeof (struct gaih_addrtuple);
+    }
+
+  (*pat)->next = NULL;
+  size_t h_name_len = strlen (host.h_name);
+  if (h_name_len >= buflen)
+    goto erange;
+  (*pat)->name = memcpy (buffer, host.h_name, h_name_len + 1);
+  (*pat)->family = host.h_addrtype;
+  memcpy ((*pat)->addr, host.h_addr_list[0], host.h_length);
+  (*pat)->scopeid = 0;
+  assert (host.h_addr_list[1] == NULL);
+
+  free (result);
+
+  return NSS_STATUS_SUCCESS;
 }
-#endif
diff --git a/nis/nss_nisplus/nisplus-hosts.c b/nis/nss_nisplus/nisplus-hosts.c
index f5f0ac96da..37d44773fc 100644
--- a/nis/nss_nisplus/nisplus-hosts.c
+++ b/nis/nss_nisplus/nisplus-hosts.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1997-2002, 2003, 2005, 2006 Free Software Foundation, Inc.
+/* Copyright (C) 1997-2003, 2005, 2006, 2008 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Thorsten Kukuk <kukuk@suse.de>, 1997.
 
@@ -17,6 +17,7 @@
    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
    02111-1307 USA.  */
 
+#include <assert.h>
 #include <atomic.h>
 #include <ctype.h>
 #include <errno.h>
@@ -58,15 +59,15 @@ _nss_nisplus_parse_hostent (nis_result *result, int af, struct hostent *host,
   if (result == NULL)
     return 0;
 
-  if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS) ||
-      __type_of (NIS_RES_OBJECT (result)) != NIS_ENTRY_OBJ ||
-      strcmp(NIS_RES_OBJECT (result)[0].EN_data.en_type, "hosts_tbl") != 0 ||
-      NIS_RES_OBJECT (result)[0].EN_data.en_cols.en_cols_len < 4)
+  if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS)
+      || __type_of (NIS_RES_OBJECT (result)) != NIS_ENTRY_OBJ
+      || strcmp (NIS_RES_OBJECT (result)[0].EN_data.en_type, "hosts_tbl") != 0
+      || NIS_RES_OBJECT (result)[0].EN_data.en_cols.en_cols_len < 4)
     return 0;
 
   char *data = first_unused;
 
-  if (room_left < (af == AF_INET6 || (flags & AI_V4MAPPED) != 0
+  if (room_left < (af != AF_INET || (flags & AI_V4MAPPED) != 0
 		   ? IN6ADDRSZ : INADDRSZ))
     {
     no_more_room:
@@ -75,8 +76,10 @@ _nss_nisplus_parse_hostent (nis_result *result, int af, struct hostent *host,
     }
 
   /* Parse address.  */
-  if (af == AF_INET && inet_pton (af, NISENTRYVAL (0, 2, result), data) > 0)
+  if (af != AF_INET6
+      && inet_pton (AF_INET, NISENTRYVAL (0, 2, result), data) > 0)
     {
+      assert ((flags & AI_V4MAPPED) == 0 || af != AF_UNSPEC);
       if (flags & AI_V4MAPPED)
 	{
 	  map_v4v6_address (data, data);
@@ -89,7 +92,7 @@ _nss_nisplus_parse_hostent (nis_result *result, int af, struct hostent *host,
 	  host->h_length = INADDRSZ;
 	}
     }
-  else if (af == AF_INET6
+  else if (af != AF_INET
 	   && inet_pton (AF_INET6, NISENTRYVAL (0, 2, result), data) > 0)
     {
       host->h_addrtype = AF_INET6;
@@ -109,27 +112,33 @@ _nss_nisplus_parse_hostent (nis_result *result, int af, struct hostent *host,
   first_unused = __stpncpy (first_unused, NISENTRYVAL (0, 0, result),
 			    NISENTRYLEN (0, 0, result));
   *first_unused++ = '\0';
-  room_left -= NISENTRYLEN (0, 0, result) + 1;
 
-  /* XXX Rewrite at some point to allocate the array first and then
-     copy the strings.  It wasteful to first concatenate the strings
-     to just split them again later.  */
+  room_left -= NISENTRYLEN (0, 0, result) + 1;
   char *line = first_unused;
-  for (i = 0; i < NIS_RES_NUMOBJ (result); ++i)
+
+  /* When this is a call to gethostbyname4_r we do not need the aliases.  */
+  if (af != AF_UNSPEC)
     {
-      if (strcmp (NISENTRYVAL (i, 1, result), host->h_name) != 0)
+      /* XXX Rewrite at some point to allocate the array first and then
+	 copy the strings.  It is wasteful to first concatenate the strings
+	 to just split them again later.  */
+      for (i = 0; i < NIS_RES_NUMOBJ (result); ++i)
 	{
-	  if (NISENTRYLEN (i, 1, result) + 2 > room_left)
-	    goto no_more_room;
-
-	  *first_unused++ = ' ';
-	  first_unused = __stpncpy (first_unused, NISENTRYVAL (i, 1, result),
-				    NISENTRYLEN (i, 1, result));
-	  *first_unused = '\0';
-	  room_left -= NISENTRYLEN (i, 1, result) + 1;
+	  if (strcmp (NISENTRYVAL (i, 1, result), host->h_name) != 0)
+	    {
+	      if (NISENTRYLEN (i, 1, result) + 2 > room_left)
+		goto no_more_room;
+
+	      *first_unused++ = ' ';
+	      first_unused = __stpncpy (first_unused,
+					NISENTRYVAL (i, 1, result),
+					NISENTRYLEN (i, 1, result));
+	      *first_unused = '\0';
+	      room_left -= NISENTRYLEN (i, 1, result) + 1;
+	    }
 	}
+      *first_unused++ = '\0';
     }
-  *first_unused++ = '\0';
 
   /* Adjust the pointer so it is aligned for
      storing pointers.  */
@@ -147,30 +156,34 @@ _nss_nisplus_parse_hostent (nis_result *result, int af, struct hostent *host,
   host->h_addr_list[1] = NULL;
   host->h_aliases = &host->h_addr_list[2];
 
-  i = 0;
-  while (*line != '\0')
+  /* When this is a call to gethostbyname4_r we do not need the aliases.  */
+  if (af != AF_UNSPEC)
     {
-      /* Skip leading blanks.  */
-      while (isspace (*line))
-	++line;
+      i = 0;
+      while (*line != '\0')
+	{
+	  /* Skip leading blanks.  */
+	  while (isspace (*line))
+	    ++line;
 
-      if (*line == '\0')
-	break;
+	  if (*line == '\0')
+	    break;
 
-      if (room_left < sizeof (char *))
-	goto no_more_room;
+	  if (room_left < sizeof (char *))
+	    goto no_more_room;
 
-      room_left -= sizeof (char *);
-      host->h_aliases[i++] = line;
+	  room_left -= sizeof (char *);
+	  host->h_aliases[i++] = line;
 
-      while (*line != '\0' && *line != ' ')
-	++line;
+	  while (*line != '\0' && *line != ' ')
+	    ++line;
 
-      if (*line == ' ')
-	*line++ = '\0';
-    }
+	  if (*line == ' ')
+	    *line++ = '\0';
+	}
 
-  host->h_aliases[i] = NULL;
+      host->h_aliases[i] = NULL;
+    }
 
   return 1;
 }
@@ -204,6 +217,7 @@ _nss_create_tablename (int *errnop)
   return NSS_STATUS_SUCCESS;
 }
 
+
 enum nss_status
 _nss_nisplus_sethostent (int stayopen)
 {
@@ -226,6 +240,7 @@ _nss_nisplus_sethostent (int stayopen)
   return status;
 }
 
+
 enum nss_status
 _nss_nisplus_endhostent (void)
 {
@@ -242,6 +257,7 @@ _nss_nisplus_endhostent (void)
   return NSS_STATUS_SUCCESS;
 }
 
+
 static enum nss_status
 internal_nisplus_gethostent_r (struct hostent *host, char *buffer,
 			       size_t buflen, int *errnop, int *herrnop)
@@ -329,6 +345,7 @@ internal_nisplus_gethostent_r (struct hostent *host, char *buffer,
   return NSS_STATUS_SUCCESS;
 }
 
+
 enum nss_status
 _nss_nisplus_gethostent_r (struct hostent *result, char *buffer,
 			   size_t buflen, int *errnop, int *herrnop)
@@ -345,26 +362,33 @@ _nss_nisplus_gethostent_r (struct hostent *result, char *buffer,
   return status;
 }
 
+
+static enum nss_status
+get_tablename (int *herrnop)
+{
+  __libc_lock_lock (lock);
+
+  enum nss_status status = _nss_create_tablename (herrnop);
+
+  __libc_lock_unlock (lock);
+
+  if (status != NSS_STATUS_SUCCESS)
+    *herrnop = NETDB_INTERNAL;
+
+  return status;
+}
+
+
 static enum nss_status
 internal_gethostbyname2_r (const char *name, int af, struct hostent *host,
 			   char *buffer, size_t buflen, int *errnop,
 			   int *herrnop, int flags)
 {
-  int parse_res, retval;
-
   if (tablename_val == NULL)
     {
-      __libc_lock_lock (lock);
-
-      enum nss_status status = _nss_create_tablename (errnop);
-
-      __libc_lock_unlock (lock);
-
+      enum nss_status status = get_tablename (herrnop);
       if (status != NSS_STATUS_SUCCESS)
-	{
-	  *herrnop = NETDB_INTERNAL;
-	  return NSS_STATUS_UNAVAIL;
-	}
+	return status;
     }
 
   if (name == NULL)
@@ -374,39 +398,36 @@ internal_gethostbyname2_r (const char *name, int af, struct hostent *host,
       return NSS_STATUS_NOTFOUND;
     }
 
-  nis_result *result;
   char buf[strlen (name) + 10 + tablename_len];
   int olderr = errno;
 
   /* Search at first in the alias list, and use the correct name
      for the next search.  */
   snprintf (buf, sizeof (buf), "[name=%s],%s", name, tablename_val);
-  result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
+  nis_result *result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 
   if (result != NULL)
     {
-      char *bufptr = buf;
-
       /* If we did not find it, try it as original name. But if the
 	 database is correct, we should find it in the first case, too.  */
-      if ((result->status != NIS_SUCCESS
-	   && result->status != NIS_S_SUCCESS)
-	  || __type_of (result->objects.objects_val) != NIS_ENTRY_OBJ
-	  || strcmp (result->objects.objects_val->EN_data.en_type,
-		     "hosts_tbl") != 0
-	  || result->objects.objects_val->EN_data.en_cols.en_cols_len < 3)
-	snprintf (buf, sizeof (buf), "[cname=%s],%s", name, tablename_val);
-      else
+      char *bufptr = buf;
+      size_t buflen = sizeof (buf);
+
+      if ((result->status == NIS_SUCCESS || result->status == NIS_S_SUCCESS)
+	  && __type_of (result->objects.objects_val) == NIS_ENTRY_OBJ
+	  && strcmp (result->objects.objects_val->EN_data.en_type,
+		     "hosts_tbl") == 0
+	  && result->objects.objects_val->EN_data.en_cols.en_cols_len >= 3)
 	{
 	  /* We need to allocate a new buffer since there is no
-	     guarantee the returned name has a length limit.  */
-	  const char *entryval = NISENTRYVAL(0, 0, result);
-	  size_t buflen = strlen (entryval) + 10 + tablename_len;
+	     guarantee the returned alias name has a length limit.  */
+	  name = NISENTRYVAL(0, 0, result);
+	  size_t buflen = strlen (name) + 10 + tablename_len;
 	  bufptr = alloca (buflen);
-	  snprintf (bufptr, buflen, "[cname=%s],%s",
-		    entryval, tablename_val);
 	}
 
+      snprintf (bufptr, buflen, "[cname=%s],%s", name, tablename_val);
+
       nis_freeresult (result);
       result = nis_list (bufptr, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
     }
@@ -417,7 +438,7 @@ internal_gethostbyname2_r (const char *name, int af, struct hostent *host,
       return NSS_STATUS_TRYAGAIN;
     }
 
-  retval = niserr2nss (result->status);
+  int retval = niserr2nss (result->status);
   if (__builtin_expect (retval != NSS_STATUS_SUCCESS, 0))
     {
       if (retval == NSS_STATUS_TRYAGAIN)
@@ -431,8 +452,8 @@ internal_gethostbyname2_r (const char *name, int af, struct hostent *host,
       return retval;
     }
 
-  parse_res = _nss_nisplus_parse_hostent (result, af, host, buffer,
-					  buflen, errnop, flags);
+  int parse_res = _nss_nisplus_parse_hostent (result, af, host, buffer,
+					      buflen, errnop, flags);
 
   nis_freeresult (result);
 
@@ -450,16 +471,24 @@ internal_gethostbyname2_r (const char *name, int af, struct hostent *host,
   return NSS_STATUS_NOTFOUND;
 }
 
+
 enum nss_status
 _nss_nisplus_gethostbyname2_r (const char *name, int af, struct hostent *host,
 			       char *buffer, size_t buflen, int *errnop,
 			       int *herrnop)
 {
+  if (af != AF_INET && af != AF_INET6)
+    {
+      *herrnop = HOST_NOT_FOUND;
+      return NSS_STATUS_NOTFOUND;
+    }
+
   return internal_gethostbyname2_r (name, af, host, buffer, buflen, errnop,
 				    herrnop,
 			 ((_res.options & RES_USE_INET6) ? AI_V4MAPPED : 0));
 }
 
+
 enum nss_status
 _nss_nisplus_gethostbyname_r (const char *name, struct hostent *host,
 			      char *buffer, size_t buflen, int *errnop,
@@ -480,6 +509,7 @@ _nss_nisplus_gethostbyname_r (const char *name, struct hostent *host,
 				   buflen, errnop, h_errnop, 0);
 }
 
+
 enum nss_status
 _nss_nisplus_gethostbyaddr_r (const void *addr, socklen_t addrlen, int af,
 			      struct hostent *host, char *buffer,
@@ -487,12 +517,7 @@ _nss_nisplus_gethostbyaddr_r (const void *addr, socklen_t addrlen, int af,
 {
   if (tablename_val == NULL)
     {
-      __libc_lock_lock (lock);
-
-      enum nss_status status = _nss_create_tablename (errnop);
-
-      __libc_lock_unlock (lock);
-
+      enum nss_status status = get_tablename (herrnop);
       if (status != NSS_STATUS_SUCCESS)
 	return status;
     }
@@ -547,3 +572,44 @@ _nss_nisplus_gethostbyaddr_r (const void *addr, socklen_t addrlen, int af,
   __set_errno (olderr);
   return NSS_STATUS_NOTFOUND;
 }
+
+
+enum nss_status
+_nss_nisplus_gethostbyname4_r (const char *name, struct gaih_addrtuple **pat,
+			       char *buffer, size_t buflen, int *errnop,
+			       int *herrnop, int32_t *ttlp)
+{
+  struct hostent host;
+
+  enum nss_status status = internal_gethostbyname2_r (name, AF_UNSPEC, &host,
+						      buffer, buflen,
+						      errnop, herrnop, 0);
+  if (__builtin_expect (status == NSS_STATUS_SUCCESS, 1))
+    {
+      if (*pat == NULL)
+	{
+	  uintptr_t pad = (-(uintptr_t) buffer
+			   % __alignof__ (struct gaih_addrtuple));
+	  buffer += pad;
+	  buflen = buflen > pad ? buflen - pad : 0;
+
+	  if (__builtin_expect (buflen < sizeof (struct gaih_addrtuple), 0))
+	    {
+	      free (result);
+	      *errnop = ERANGE;
+	      *herrnop = NETDB_INTERNAL;
+	      return NSS_STATUS_TRYAGAIN;
+	    }
+	}
+
+      (*pat)->next = NULL;
+      (*pat)->name = host.h_name;
+      (*pat)->family = host.h_addrtype;
+
+      memcpy ((*pat)->addr, host.h_addr_list[0], host.h_length);
+      (*pat)->scopeid = 0;
+      assert (host.h_addr_list[1] == NULL);
+    }
+
+  return status;
+}
diff --git a/nscd/aicache.c b/nscd/aicache.c
index 2518f80128..4db3e65bd1 100644
--- a/nscd/aicache.c
+++ b/nscd/aicache.c
@@ -21,6 +21,7 @@
 #include <errno.h>
 #include <libintl.h>
 #include <netdb.h>
+#include <nss.h>
 #include <string.h>
 #include <time.h>
 #include <unistd.h>
@@ -33,6 +34,10 @@
 #endif
 
 
+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,
@@ -117,16 +122,104 @@ addhstaiX (struct database_dyn *db, int fd, request_header *req,
 
   while (!no_more)
     {
+      void *cp;
       int status[2] = { NSS_STATUS_UNAVAIL, NSS_STATUS_UNAVAIL };
+      int naddrs = 0;
+      size_t addrslen = 0;
+      size_t canonlen;
+
+      nss_gethostbyname4_r fct4 = __nss_lookup_function (nip,
+							 "gethostbyname4_r");
+      if (fct4 != NULL)
+	{
+	  struct gaih_addrtuple *at = NULL;
+	  while (1)
+	    {
+	      rc6 = 0;
+	      status[0] = DL_CALL_FCT (fct4, (key, &at, tmpbuf6, tmpbuf6len,
+					      &rc6, &herrno, &ttl));
+	      if (rc6 != ERANGE || herrno != NETDB_INTERNAL)
+		break;
+	      tmpbuf6 = extend_alloca (tmpbuf6, tmpbuf6len, 2 * tmpbuf6len);
+	    }
+
+	  if (rc6 != 0 && herrno == NETDB_INTERNAL)
+	    goto out;
 
-      /* Prefer the function which also returns the TTL and canonical name.  */
-      nss_gethostbyname3_r fct = __nss_lookup_function (nip,
-							"gethostbyname3_r");
-      if (fct == NULL)
-	fct = __nss_lookup_function (nip, "gethostbyname2_r");
+	  if (status[0] != NSS_STATUS_SUCCESS)
+	    goto next_nip;
+
+	  /* We found the data.  Count the addresses and the size.  */
+	  for (struct gaih_addrtuple *at2 = at; at2 != NULL; at2 = at2->next)
+	    {
+	      ++naddrs;
+	      /* We handle unknown types here the best we can: assume
+		 the maximum size for the address.  */
+	      if (at2->family == AF_INET)
+		addrslen += INADDRSZ;
+	      else if (at2->family == AF_INET6
+		       && IN6ADDRSZ != sizeof (at2->addr))
+		addrslen += IN6ADDRSZ;
+	      else
+		addrslen += sizeof (at2->addr);
+	    }
+	  canon = at->name;
+	  canonlen = strlen (canon) + 1;
+
+	  total = sizeof (*dataset) + naddrs + addrslen + canonlen;
+
+	  /* Now we can allocate the data structure.  If the TTL of the
+	     entry is reported as zero do not cache the entry at all.  */
+	  if (ttl != 0 && he == NULL)
+	    {
+	      dataset = (struct dataset *) mempool_alloc (db, total
+							  + req->key_len,
+							  IDX_result_data);
+	      if (dataset == NULL)
+		++db->head->addfailed;
+	    }
+
+	  if (dataset == NULL)
+	    {
+	      /* We cannot permanently add the result in the moment.  But
+		 we can provide the result as is.  Store the data in some
+		 temporary memory.  */
+	      dataset = (struct dataset *) alloca (total + req->key_len);
+
+	      /* We cannot add this record to the permanent database.  */
+	      alloca_used = true;
+	    }
 
-      if (fct != NULL)
+	  /* Fill in the address and address families.  */
+	  char *addrs = (char *) (&dataset->resp + 1);
+	  uint8_t *family = (uint8_t *) (addrs + addrslen);
+
+	  for (struct gaih_addrtuple *at2 = at; at2 != NULL; at2 = at2->next)
+	    {
+	      *family++ = at2->family;
+	      if (at2->family == AF_INET)
+		addrs = mempcpy (addrs, at2->addr, INADDRSZ);
+	      else if (at2->family == AF_INET6
+		       && IN6ADDRSZ != sizeof (at2->addr))
+		addrs = mempcpy (addrs, at2->addr, IN6ADDRSZ);
+	      else
+		addrs = mempcpy (addrs, at2->addr, sizeof (at2->addr));
+	    }
+
+	  cp = family;
+	}
+      else
 	{
+	  /* Prefer the function which also returns the TTL and
+	     canonical name.  */
+	  nss_gethostbyname3_r fct = __nss_lookup_function (nip,
+							    "gethostbyname3_r");
+	  if (fct == NULL)
+	    fct = __nss_lookup_function (nip, "gethostbyname2_r");
+
+	  if (fct == NULL)
+	    goto next_nip;
+
 	  struct hostent th[2];
 
 	  /* Collect IPv6 information first.  */
@@ -134,8 +227,8 @@ addhstaiX (struct database_dyn *db, int fd, request_header *req,
 	    {
 	      rc6 = 0;
 	      status[0] = DL_CALL_FCT (fct, (key, AF_INET6, &th[0], tmpbuf6,
-					     tmpbuf6len, &rc6, &herrno,
-					     &ttl, &canon));
+					     tmpbuf6len, &rc6, &herrno, &ttl,
+					     &canon));
 	      if (rc6 != ERANGE || herrno != NETDB_INTERNAL)
 		break;
 	      tmpbuf6 = extend_alloca (tmpbuf6, tmpbuf6len, 2 * tmpbuf6len);
@@ -173,231 +266,226 @@ addhstaiX (struct database_dyn *db, int fd, request_header *req,
 	  if (rc4 != 0 && herrno == NETDB_INTERNAL)
 	    goto out;
 
-	  if (status[0] == NSS_STATUS_SUCCESS
-	      || status[1] == NSS_STATUS_SUCCESS)
+	  if (status[0] != NSS_STATUS_SUCCESS
+	      && status[1] != NSS_STATUS_SUCCESS)
+	    goto next_nip;
+
+	  /* We found the data.  Count the addresses and the size.  */
+	  for (int j = 0; j < 2; ++j)
+	    if (status[j] == NSS_STATUS_SUCCESS)
+	      for (int i = 0; th[j].h_addr_list[i] != NULL; ++i)
+		{
+		  ++naddrs;
+		  addrslen += th[j].h_length;
+		}
+
+	  if (canon == NULL)
 	    {
-	      /* We found the data.  Count the addresses and the size.  */
-	      int naddrs = 0;
-	      size_t addrslen = 0;
-	      for (int j = 0; j < 2; ++j)
-		if (status[j] == NSS_STATUS_SUCCESS)
-		  for (int i = 0; th[j].h_addr_list[i] != NULL; ++i)
+	      /* Determine the canonical name.  */
+	      nss_getcanonname_r cfct;
+	      cfct = __nss_lookup_function (nip, "getcanonname_r");
+	      if (cfct != NULL)
+		{
+		  const size_t max_fqdn_len = 256;
+		  char *buf = alloca (max_fqdn_len);
+		  char *s;
+		  int rc;
+
+		  if (DL_CALL_FCT (cfct, (key, buf, max_fqdn_len, &s,
+					  &rc, &herrno))
+		      == NSS_STATUS_SUCCESS)
+		    canon = s;
+		  else
+		    /* Set to name now to avoid using gethostbyaddr.  */
+		    canon = key;
+		}
+	      else
+		{
+		  struct hostent *he = NULL;
+		  int herrno;
+		  struct hostent he_mem;
+		  void *addr;
+		  size_t addrlen;
+		  int addrfamily;
+
+		  if (status[1] == NSS_STATUS_SUCCESS)
+		    {
+		      addr = th[1].h_addr_list[0];
+		      addrlen = sizeof (struct in_addr);
+		      addrfamily = AF_INET;
+		    }
+		  else
 		    {
-		      ++naddrs;
-		      addrslen += th[j].h_length;
+		      addr = th[0].h_addr_list[0];
+		      addrlen = sizeof (struct in6_addr);
+		      addrfamily = AF_INET6;
 		    }
 
-	      if (canon == NULL)
-		{
-		  /* Determine the canonical name.  */
-		  nss_getcanonname_r cfct;
-		  cfct = __nss_lookup_function (nip, "getcanonname_r");
-		  if (cfct != NULL)
+		  size_t tmpbuflen = 512;
+		  char *tmpbuf = alloca (tmpbuflen);
+		  int rc;
+		  while (1)
 		    {
-		      const size_t max_fqdn_len = 256;
-		      char *buf = alloca (max_fqdn_len);
-		      char *s;
-		      int rc;
-
-		      if (DL_CALL_FCT (cfct, (key, buf, max_fqdn_len, &s, &rc,
-					      &herrno)) == NSS_STATUS_SUCCESS)
-			canon = s;
-		      else
-			/* Set to name now to avoid using gethostbyaddr.  */
-			canon = key;
+		      rc = __gethostbyaddr2_r (addr, addrlen, addrfamily,
+					       &he_mem, tmpbuf, tmpbuflen,
+					       &he, &herrno, NULL);
+		      if (rc != ERANGE || herrno != NETDB_INTERNAL)
+			break;
+		      tmpbuf = extend_alloca (tmpbuf, tmpbuflen,
+					      tmpbuflen * 2);
 		    }
-		  else
+
+		  if (rc == 0)
 		    {
-		      struct hostent *he = NULL;
-		      int herrno;
-		      struct hostent he_mem;
-		      void *addr;
-		      size_t addrlen;
-		      int addrfamily;
-
-		      if (status[1] == NSS_STATUS_SUCCESS)
-			{
-			  addr = th[1].h_addr_list[0];
-			  addrlen = sizeof (struct in_addr);
-			  addrfamily = AF_INET;
-			}
+		      if (he != NULL)
+			canon = he->h_name;
 		      else
-			{
-			  addr = th[0].h_addr_list[0];
-			  addrlen = sizeof (struct in6_addr);
-			  addrfamily = AF_INET6;
-			}
-
-		      size_t tmpbuflen = 512;
-		      char *tmpbuf = alloca (tmpbuflen);
-		      int rc;
-		      while (1)
-			{
-			  rc = __gethostbyaddr2_r (addr, addrlen, addrfamily,
-						   &he_mem, tmpbuf, tmpbuflen,
-						   &he, &herrno, NULL);
-			  if (rc != ERANGE || herrno != NETDB_INTERNAL)
-			    break;
-			  tmpbuf = extend_alloca (tmpbuf, tmpbuflen,
-						  tmpbuflen * 2);
-			}
-
-		      if (rc == 0)
-			{
-			  if (he != NULL)
-			    canon = he->h_name;
-			  else
-			    canon = key;
-			}
+			canon = key;
 		    }
 		}
-	      size_t canonlen = canon == NULL ? 0 : (strlen (canon) + 1);
+	    }
 
-	      total = sizeof (*dataset) + naddrs + addrslen + canonlen;
+	  canonlen = canon == NULL ? 0 : (strlen (canon) + 1);
+
+	  total = sizeof (*dataset) + naddrs + addrslen + canonlen;
 
-	      /* Now we can allocate the data structure.  If the TTL
-		 of the entry is reported as zero do not cache the
-		 entry at all.  */
-	      if (ttl != 0 && he == NULL)
-		{
-		  dataset = (struct dataset *) mempool_alloc (db,
-							      total
-							      + req->key_len,
-							      IDX_result_data);
-		  if (dataset == NULL)
-		    ++db->head->addfailed;
-		}
 
+	  /* Now we can allocate the data structure.  If the TTL of the
+	     entry is reported as zero do not cache the entry at all.  */
+	  if (ttl != 0 && he == NULL)
+	    {
+	      dataset = (struct dataset *) mempool_alloc (db, total
+							  + req->key_len,
+							  IDX_result_data);
 	      if (dataset == NULL)
-		{
-		  /* We cannot permanently add the result in the moment.  But
-		     we can provide the result as is.  Store the data in some
-		     temporary memory.  */
-		  dataset = (struct dataset *) alloca (total + req->key_len);
+		++db->head->addfailed;
+	    }
+
+	  if (dataset == NULL)
+	    {
+	      /* We cannot permanently add the result in the moment.  But
+		 we can provide the result as is.  Store the data in some
+		 temporary memory.  */
+	      dataset = (struct dataset *) alloca (total + req->key_len);
+
+	      /* We cannot add this record to the permanent database.  */
+	      alloca_used = true;
+	    }
 
-		  /* We cannot add this record to the permanent database.  */
-		  alloca_used = true;
+	  /* Fill in the address and address families.  */
+	  char *addrs = (char *) (&dataset->resp + 1);
+	  uint8_t *family = (uint8_t *) (addrs + addrslen);
+
+	  for (int j = 0; j < 2; ++j)
+	    if (status[j] == NSS_STATUS_SUCCESS)
+	      for (int i = 0; th[j].h_addr_list[i] != NULL; ++i)
+		{
+		  addrs = mempcpy (addrs, th[j].h_addr_list[i],
+				   th[j].h_length);
+		  *family++ = th[j].h_addrtype;
 		}
 
-	      dataset->head.allocsize = total + req->key_len;
-	      dataset->head.recsize = total - offsetof (struct dataset, resp);
-	      dataset->head.notfound = false;
-	      dataset->head.nreloads = he == NULL ? 0 : (dh->nreloads + 1);
-	      dataset->head.usable = true;
-
-	      /* Compute the timeout time.  */
-	      dataset->head.timeout = time (NULL) + (ttl == INT32_MAX
-						     ? db->postimeout : ttl);
-
-	      dataset->resp.version = NSCD_VERSION;
-	      dataset->resp.found = 1;
-	      dataset->resp.naddrs = naddrs;
-	      dataset->resp.addrslen = addrslen;
-	      dataset->resp.canonlen = canonlen;
-	      dataset->resp.error = NETDB_SUCCESS;
-
-	      char *addrs = (char *) (&dataset->resp + 1);
-	      uint8_t *family = (uint8_t *) (addrs + addrslen);
-
-	      for (int j = 0; j < 2; ++j)
-		if (status[j] == NSS_STATUS_SUCCESS)
-		  for (int i = 0; th[j].h_addr_list[i] != NULL; ++i)
-		    {
-		      addrs = mempcpy (addrs, th[j].h_addr_list[i],
-				       th[j].h_length);
-		      *family++ = th[j].h_addrtype;
-		    }
+	  cp = family;
+	}
 
-	      void *cp = family;
-	      if (canon != NULL)
-		cp = mempcpy (cp, canon, canonlen);
+      /* Fill in the rest of the dataset.  */
+      dataset->head.allocsize = total + req->key_len;
+      dataset->head.recsize = total - offsetof (struct dataset, resp);
+      dataset->head.notfound = false;
+      dataset->head.nreloads = he == NULL ? 0 : (dh->nreloads + 1);
+      dataset->head.usable = true;
 
-	      key_copy = memcpy (cp, key, req->key_len);
+      /* Compute the timeout time.  */
+      dataset->head.timeout = time (NULL) + (ttl == INT32_MAX
+					     ? db->postimeout : ttl);
 
-	      /* Now we can determine whether on refill we have to
-		 create a new record or not.  */
-	      if (he != NULL)
-		{
-		  assert (fd == -1);
+      dataset->resp.version = NSCD_VERSION;
+      dataset->resp.found = 1;
+      dataset->resp.naddrs = naddrs;
+      dataset->resp.addrslen = addrslen;
+      dataset->resp.canonlen = canonlen;
+      dataset->resp.error = NETDB_SUCCESS;
 
-		  if (total + req->key_len == dh->allocsize
-		      && total - offsetof (struct dataset, resp) == dh->recsize
-		      && memcmp (&dataset->resp, dh->data,
-				 dh->allocsize
-				 - offsetof (struct dataset, resp)) == 0)
-		    {
-		      /* The data has not changed.  We will just bump the
-			 timeout value.  Note that the new record has been
-			 allocated on the stack and need not be freed.  */
-		      dh->timeout = dataset->head.timeout;
-		      ++dh->nreloads;
-		    }
-		  else
-		    {
-		      /* We have to create a new record.  Just allocate
-			 appropriate memory and copy it.  */
-		      struct dataset *newp
-			= (struct dataset *) mempool_alloc (db,
-							    total
-							    + req->key_len,
-							    IDX_result_data);
-		      if (__builtin_expect (newp != NULL, 1))
-			{
-			  /* Adjust pointer into the memory block.  */
-			  key_copy = (char *) newp + (key_copy
-						      - (char *) dataset);
-
-			  dataset = memcpy (newp, dataset,
-					    total + req->key_len);
-			  alloca_used = false;
-			}
-		      else
-			++db->head->addfailed;
+      if (canon != NULL)
+	cp = mempcpy (cp, canon, canonlen);
 
-		      /* Mark the old record as obsolete.  */
-		      dh->usable = false;
-		    }
+      key_copy = memcpy (cp, key, req->key_len);
+
+      /* Now we can determine whether on refill we have to create a
+	 new record or not.  */
+      if (he != NULL)
+	{
+	  assert (fd == -1);
+
+	  if (total + req->key_len == dh->allocsize
+	      && total - offsetof (struct dataset, resp) == dh->recsize
+	      && memcmp (&dataset->resp, dh->data,
+			 dh->allocsize - offsetof (struct dataset,
+						   resp)) == 0)
+	    {
+	      /* The data has not changed.  We will just bump the
+		 timeout value.  Note that the new record has been
+		 allocated on the stack and need not be freed.  */
+	      dh->timeout = dataset->head.timeout;
+	      ++dh->nreloads;
+	    }
+	  else
+	    {
+	      /* We have to create a new record.  Just allocate
+		 appropriate memory and copy it.  */
+	      struct dataset *newp
+		= (struct dataset *) mempool_alloc (db, total + req->key_len,
+						    IDX_result_data);
+	      if (__builtin_expect (newp != NULL, 1))
+		{
+		  /* Adjust pointer into the memory block.  */
+		  key_copy = (char *) newp + (key_copy - (char *) dataset);
+
+		  dataset = memcpy (newp, dataset, total + req->key_len);
+		  alloca_used = false;
 		}
 	      else
-		{
-		  /* We write the dataset before inserting it to the
-		     database since while inserting this thread might
-		     block and so would unnecessarily let the receiver
-		     wait.  */
-		  assert (fd != -1);
+		++db->head->addfailed;
+
+	      /* Mark the old record as obsolete.  */
+	      dh->usable = false;
+	    }
+	}
+      else
+	{
+	  /* We write the dataset before inserting it to the database
+	     since while inserting this thread might block and so
+	     would unnecessarily let the receiver wait.  */
+	  assert (fd != -1);
 
 #ifdef HAVE_SENDFILE
-		  if (__builtin_expect (db->mmap_used, 1) && !alloca_used)
-		    {
-		      assert (db->wr_fd != -1);
-		      assert ((char *) &dataset->resp > (char *) db->data);
-		      assert ((char *) &dataset->resp - (char *) db->head
-			      + total
-			      <= (sizeof (struct database_pers_head)
-				  + db->head->module * sizeof (ref_t)
-				  + db->head->data_size));
-		      ssize_t written;
-		      written = sendfileall (fd, db->wr_fd,
-					     (char *) &dataset->resp
-					     - (char *) db->head, total);
+	  if (__builtin_expect (db->mmap_used, 1) && !alloca_used)
+	    {
+	      assert (db->wr_fd != -1);
+	      assert ((char *) &dataset->resp > (char *) db->data);
+	      assert ((char *) &dataset->resp - (char *) db->head + total
+		      <= (sizeof (struct database_pers_head)
+			  + db->head->module * sizeof (ref_t)
+			  + db->head->data_size));
+	      ssize_t written;
+	      written = sendfileall (fd, db->wr_fd, (char *) &dataset->resp
+				     - (char *) db->head, total);
 # ifndef __ASSUME_SENDFILE
-		      if (written == -1 && errno == ENOSYS)
-			goto use_write;
+	      if (written == -1 && errno == ENOSYS)
+		goto use_write;
 # endif
-		    }
-		  else
+	    }
+	  else
 # ifndef __ASSUME_SENDFILE
-		  use_write:
+	  use_write:
 # endif
 #endif
-		    writeall (fd, &dataset->resp, total);
-		}
-
-	      goto out;
-	    }
-
+	    writeall (fd, &dataset->resp, total);
 	}
 
+      goto out;
+
+next_nip:
       if (nss_next_action (nip, status[1]) == NSS_ACTION_RETURN)
 	break;
 
diff --git a/nss/Versions b/nss/Versions
index 8f2f0fb371..f7f0e56979 100644
--- a/nss/Versions
+++ b/nss/Versions
@@ -38,6 +38,7 @@ libnss_files {
     _nss_files_endhostent;
     _nss_files_gethostbyaddr_r;
     _nss_files_gethostbyname2_r;
+    _nss_files_gethostbyname4_r;
     _nss_files_gethostbyname_r;
     _nss_files_gethostent_r;
     _nss_files_gethostton_r;
diff --git a/nss/nss.h b/nss/nss.h
index f5c12afab6..611b2580ad 100644
--- a/nss/nss.h
+++ b/nss/nss.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 1996, 1997, 1999 Free Software Foundation, Inc.
+/* Copyright (C) 1996, 1997, 1999, 2008 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
@@ -23,6 +23,7 @@
 #define _NSS_H	1
 
 #include <features.h>
+#include <stdint.h>
 
 
 __BEGIN_DECLS
@@ -38,6 +39,17 @@ enum nss_status
 };
 
 
+/* Data structure used for the 'gethostbyname4_r' function.  */
+struct gaih_addrtuple
+  {
+    struct gaih_addrtuple *next;
+    char *name;
+    int family;
+    uint32_t addr[4];
+    uint32_t scopeid;
+  };
+
+
 /* Overwrite service selection for database DBNAME using specification
    in STRING.
    This function should only be used by system programs which have to
diff --git a/nss/nss_files/files-hosts.c b/nss/nss_files/files-hosts.c
index b06467225b..7b69d47fcb 100644
--- a/nss/nss_files/files-hosts.c
+++ b/nss/nss_files/files-hosts.c
@@ -1,6 +1,5 @@
 /* Hosts file parser in nss_files module.
-   Copyright (C) 1996-2001, 2003, 2004, 2006, 2007
-   Free Software Foundation, Inc.
+   Copyright (C) 1996-2001, 2003-2007, 2008 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
@@ -56,7 +55,10 @@ LINE_PARSER
    STRING_FIELD (addr, isspace, 1);
 
    /* Parse address.  */
-   if (inet_pton (af, addr, entdata->host_addr) <= 0)
+   if (inet_pton (af == AF_UNSPEC ? AF_INET : af, addr, entdata->host_addr)
+       > 0)
+     af = af == AF_UNSPEC ? AF_INET : af;
+   else
      {
        if (af == AF_INET6 && (flags & AI_V4MAPPED) != 0
 	   && inet_pton (AF_INET, addr, entdata->host_addr) > 0)
@@ -76,6 +78,9 @@ LINE_PARSER
 	     /* Illegal address: ignore line.  */
 	     return 0;
 	 }
+       else if (af == AF_UNSPEC
+		&& inet_pton (AF_INET6, addr, entdata->host_addr) > 0)
+	 af = AF_INET6;
        else
 	 /* Illegal address: ignore line.  */
 	 return 0;
@@ -101,8 +106,6 @@ _nss_files_get##name##_r (proto,					      \
 			  struct STRUCTURE *result, char *buffer,	      \
 			  size_t buflen, int *errnop H_ERRNO_PROTO)	      \
 {									      \
-  enum nss_status status;						      \
-									      \
   uintptr_t pad = -(uintptr_t) buffer % __alignof__ (struct hostent_data);    \
   buffer += pad;							      \
   buflen = buflen > pad ? buflen - pad : 0;				      \
@@ -110,7 +113,7 @@ _nss_files_get##name##_r (proto,					      \
   __libc_lock_lock (lock);						      \
 									      \
   /* Reset file pointer to beginning or open file.  */			      \
-  status = internal_setent (keep_stream);				      \
+  enum nss_status status = internal_setent (keep_stream);		      \
 									      \
   if (status == NSS_STATUS_SUCCESS)					      \
     {									      \
@@ -288,9 +291,9 @@ HOST_DB_LOOKUP (hostbyname, ,,
 		{
 		  LOOKUP_NAME_CASE (h_name, h_aliases)
 		}, const char *name)
+#undef EXTRA_ARGS_VALUE
 
 
-#undef EXTRA_ARGS_VALUE
 /* XXX Is using _res to determine whether we want to convert IPv4 addresses
    to IPv6 addresses really the right thing to do?  */
 #define EXTRA_ARGS_VALUE \
@@ -299,8 +302,9 @@ HOST_DB_LOOKUP (hostbyname2, ,,
 		{
 		  LOOKUP_NAME_CASE (h_name, h_aliases)
 		}, const char *name, int af)
-
 #undef EXTRA_ARGS_VALUE
+
+
 /* We only need to consider IPv4 mapped addresses if the input to the
    gethostbyaddr() function is an IPv6 address.  */
 #define EXTRA_ARGS_VALUE \
@@ -311,3 +315,116 @@ DB_LOOKUP (hostbyaddr, ,,
 		 && ! memcmp (addr, result->h_addr_list[0], len))
 	       break;
 	   }, const void *addr, socklen_t len, int af)
+#undef EXTRA_ARGS_VALUE
+
+
+enum nss_status
+_nss_files_gethostbyname4_r (const char *name, struct gaih_addrtuple **pat,
+			     char *buffer, size_t buflen, int *errnop,
+			     int *herrnop, int32_t *ttlp)
+{
+  __libc_lock_lock (lock);
+
+  /* Reset file pointer to beginning or open file.  */
+  enum nss_status status = internal_setent (keep_stream);
+
+  if (status == NSS_STATUS_SUCCESS)
+    {
+      /* Tell getent function that we have repositioned the file pointer.  */
+      last_use = getby;
+
+      bool any = false;
+      bool got_canon = false;
+      while (1)
+	{
+	  /* Align the buffer for the next record.  */
+	  uintptr_t pad = (-(uintptr_t) buffer
+			   % __alignof__ (struct hostent_data));
+	  buffer += pad;
+	  buflen = buflen > pad ? buflen - pad : 0;
+
+	  struct hostent result;
+	  status = internal_getent (&result, buffer, buflen, errnop
+				    H_ERRNO_ARG, AF_UNSPEC, 0);
+	  if (status != NSS_STATUS_SUCCESS)
+	    break;
+
+	  int naliases = 0;
+	  if (__strcasecmp (name, result.h_name) != 0)
+	    {
+	      for (; result.h_aliases[naliases] != NULL; ++naliases)
+		if (! __strcasecmp (name, result.h_aliases[naliases]))
+		  break;
+	      if (result.h_aliases[naliases] == NULL)
+		continue;
+
+	      /* We know this alias exist.  Count it.  */
+	      ++naliases;
+	    }
+
+	  /* Determine how much memory has been used so far.  */
+	  // XXX It is not necessary to preserve the aliases array
+	  while (result.h_aliases[naliases] != NULL)
+	    ++naliases;
+	  char *bufferend = (char *) &result.h_aliases[naliases + 1];
+	  assert (buflen >= bufferend - buffer);
+	  buflen -= bufferend - buffer;
+	  buffer = bufferend;
+
+	  /* We found something.  */
+	  any = true;
+
+	  /* Create the record the caller expects.  There is only one
+	     address.  */
+	  assert (result.h_addr_list[1] == NULL);
+	  if (*pat == NULL)
+	    {
+	      uintptr_t pad = (-(uintptr_t) buffer
+			       % __alignof__ (struct gaih_addrtuple));
+	      buffer += pad;
+	      buflen = buflen > pad ? buflen - pad : 0;
+
+	      if (__builtin_expect (buflen < sizeof (struct gaih_addrtuple),
+				    0))
+		{
+		  *errnop = ERANGE;
+		  *herrnop = NETDB_INTERNAL;
+		  status = NSS_STATUS_TRYAGAIN;
+		  break;
+		}
+
+	      *pat = (struct gaih_addrtuple *) buffer;
+	      buffer += sizeof (struct gaih_addrtuple);
+	      buflen -= sizeof (struct gaih_addrtuple);
+	    }
+
+	  (*pat)->next = NULL;
+	  (*pat)->name = got_canon ? NULL : result.h_name;
+	  got_canon = true;
+	  (*pat)->family = result.h_addrtype;
+	  memcpy ((*pat)->addr, result.h_addr_list[0], result.h_length);
+	  (*pat)->scopeid = 0;
+
+	  pat = &((*pat)->next);
+
+	  /* If we only look for the first matching entry we are done.  */
+	  if ((_res_hconf.flags & HCONF_FLAG_MULTI) == 0)
+	    break;
+	}
+
+      /* If we have to look for multiple records and found one, this
+	 is a success.  */
+      if (status == NSS_STATUS_NOTFOUND && any)
+	{
+	  assert ((_res_hconf.flags & HCONF_FLAG_MULTI) != 0);
+	  status = NSS_STATUS_SUCCESS;
+	}
+
+      if (! keep_stream)
+	internal_endent ();
+    }
+
+  __libc_lock_unlock (lock);
+
+  return status;
+}
diff --git a/resolv/Versions b/resolv/Versions
index fc2111a1cb..355d95d606 100644
--- a/resolv/Versions
+++ b/resolv/Versions
@@ -89,6 +89,7 @@ libnss_dns {
     _nss_dns_gethostbyname_r; _nss_dns_getnetbyaddr_r;
     _nss_dns_getnetbyname_r; _nss_dns_getcanonname_r;
     _nss_dns_gethostbyaddr2_r;
+    _nss_dns_gethostbyname4_r;
   }
 }
 
diff --git a/resolv/gethnamaddr.c b/resolv/gethnamaddr.c
index 7be23158d0..2a9bd0b3c2 100644
--- a/resolv/gethnamaddr.c
+++ b/resolv/gethnamaddr.c
@@ -621,7 +621,7 @@ gethostbyname2(name, af)
 	buf.buf = origbuf = (querybuf *) alloca (1024);
 
 	if ((n = __libc_res_nsearch(&_res, name, C_IN, type, buf.buf->buf, 1024,
-				    &buf.ptr)) < 0) {
+				    &buf.ptr, NULL, NULL)) < 0) {
 		if (buf.buf != origbuf)
 			free (buf.buf);
 		Dprintf("res_nsearch failed (%d)\n", n);
@@ -716,12 +716,12 @@ gethostbyaddr(addr, len, af)
 	buf.buf = orig_buf = (querybuf *) alloca (1024);
 
 	n = __libc_res_nquery(&_res, qbuf, C_IN, T_PTR, buf.buf->buf, 1024,
-			      &buf.ptr);
+			      &buf.ptr, NULL, NULL);
 	if (n < 0 && af == AF_INET6 && (_res.options & RES_NOIP6DOTINT) == 0) {
 		strcpy(qp, "ip6.int");
 		n = __libc_res_nquery(&_res, qbuf, C_IN, T_PTR, buf.buf->buf,
 				      buf.buf != orig_buf ? MAXPACKET : 1024,
-				      &buf.ptr);
+				      &buf.ptr, NULL, NULL);
 	}
 	if (n < 0) {
 		if (buf.buf != orig_buf)
diff --git a/resolv/nss_dns/dns-canon.c b/resolv/nss_dns/dns-canon.c
index fca6cd8997..47949b862f 100644
--- a/resolv/nss_dns/dns-canon.c
+++ b/resolv/nss_dns/dns-canon.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2004, 2006 Free Software Foundation, Inc.
+/* Copyright (C) 2004, 2006, 2008 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@redhat.com>, 2004.
 
@@ -61,7 +61,7 @@ _nss_dns_getcanonname_r (const char *name, char *buffer, size_t buflen,
   for (int i = 0; i < nqtypes; ++i)
     {
       int r = __libc_res_nquery (&_res, name, ns_c_in, qtypes[i],
-				 buf, sizeof (buf), &ansp.ptr);
+				 buf, sizeof (buf), &ansp.ptr, NULL, NULL);
       if (r > 0)
 	{
 	  /* We need to decode the response.  Just one question record.
diff --git a/resolv/nss_dns/dns-host.c b/resolv/nss_dns/dns-host.c
index dfdf9c5dcb..c52f9f7f84 100644
--- a/resolv/nss_dns/dns-host.c
+++ b/resolv/nss_dns/dns-host.c
@@ -71,6 +71,7 @@
  * --Copyright--
  */
 
+#include <assert.h>
 #include <ctype.h>
 #include <errno.h>
 #include <netdb.h>
@@ -127,6 +128,14 @@ static enum nss_status getanswer_r (const querybuf *answer, int anslen,
 				    size_t buflen, int *errnop, int *h_errnop,
 				    int map, int32_t *ttlp, char **canonp);
 
+static enum nss_status gaih_getanswer (const querybuf *answer1, int anslen1,
+				       const querybuf *answer2, int anslen2,
+				       const char *qname,
+				       struct gaih_addrtuple **pat,
+				       char *buffer, size_t buflen,
+				       int *errnop, int *h_errnop,
+				       int32_t *ttlp);
+
 extern enum nss_status _nss_dns_gethostbyname3_r (const char *name, int af,
 						  struct hostent *result,
 						  char *buffer, size_t buflen,
@@ -186,11 +195,11 @@ _nss_dns_gethostbyname3_r (const char *name, int af, struct hostent *result,
   host_buffer.buf = orig_host_buffer = (querybuf *) alloca (1024);
 
   n = __libc_res_nsearch (&_res, name, C_IN, type, host_buffer.buf->buf,
-			  1024, &host_buffer.ptr);
+			  1024, &host_buffer.ptr, NULL, NULL);
   if (n < 0)
     {
-      enum nss_status status = (errno == ECONNREFUSED
-				? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND);
+      status = (errno == ECONNREFUSED
+		? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND);
       *h_errnop = h_errno;
       if (h_errno == TRY_AGAIN)
 	*errnop = EAGAIN;
@@ -203,7 +212,8 @@ _nss_dns_gethostbyname3_r (const char *name, int af, struct hostent *result,
       if (af == AF_INET6 && (_res.options & RES_USE_INET6))
 	n = __libc_res_nsearch (&_res, name, C_IN, T_A, host_buffer.buf->buf,
 				host_buffer.buf != orig_host_buffer
-				? MAXPACKET : 1024, &host_buffer.ptr);
+				? MAXPACKET : 1024, &host_buffer.ptr,
+				NULL, NULL);
 
       if (n < 0)
 	{
@@ -255,6 +265,70 @@ _nss_dns_gethostbyname_r (const char *name, struct hostent *result,
 }
 
 
+enum nss_status
+_nss_dns_gethostbyname4_r (const char *name, struct gaih_addrtuple **pat,
+			   char *buffer, size_t buflen, int *errnop,
+			   int *herrnop, int32_t *ttlp)
+{
+  if (__res_maybe_init (&_res, 0) == -1)
+    return NSS_STATUS_UNAVAIL;
+
+  char tmp[NS_MAXDNAME];
+
+  /*
+   * if there aren't any dots, it could be a user-level alias.
+   * this is also done in res_query() since we are not the only
+   * function that looks up host names.
+   */
+  if (strchr (name, '.') == NULL)
+    {
+      const char *cp = res_hostalias (&_res, name, tmp, sizeof (tmp));
+      if (cp != NULL)
+	name = cp;
+    }
+
+  union
+  {
+    querybuf *buf;
+    u_char *ptr;
+  } host_buffer;
+  querybuf *orig_host_buffer;
+  host_buffer.buf = orig_host_buffer = (querybuf *) alloca (2048);
+  u_char *ans2p = NULL;
+  int nans2p = 0;
+
+  int olderr = errno;
+  enum nss_status status;
+  int n = __libc_res_nsearch (&_res, name, C_IN, T_UNSPEC,
+			      host_buffer.buf->buf, 2048, &host_buffer.ptr,
+			      &ans2p, &nans2p);
+  if (n < 0)
+    {
+      status = (errno == ECONNREFUSED
+		? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND);
+      *herrnop = h_errno;
+      if (h_errno == TRY_AGAIN)
+	*errnop = EAGAIN;
+      else
+	__set_errno (olderr);
+
+      if (host_buffer.buf != orig_host_buffer)
+	free (host_buffer.buf);
+
+      return status;
+    }
+
+  status = gaih_getanswer(host_buffer.buf, n, (const querybuf *) ans2p,
+			  nans2p, name, pat, buffer, buflen,
+			  errnop, herrnop, ttlp);
+
+  if (host_buffer.buf != orig_host_buffer)
+    free (host_buffer.buf);
+
+  return status;
+}
+
+
 extern enum nss_status _nss_dns_gethostbyaddr2_r (const void *addr,
 						  socklen_t len, int af,
 						  struct hostent *result,
@@ -342,7 +416,8 @@ _nss_dns_gethostbyaddr2_r (const void *addr, socklen_t len, int af,
 	    qp += sprintf (qp, "%02hhx", uaddr[n]);
 	  strcpy (qp, "].ip6.arpa");
 	  n = __libc_res_nquery (&_res, qbuf, C_IN, T_PTR,
-				 host_buffer.buf->buf, 1024, &host_buffer.ptr);
+				 host_buffer.buf->buf, 1024, &host_buffer.ptr,
+				 NULL, NULL);
 	  if (n >= 0)
 	    goto got_it_already;
 	}
@@ -363,13 +438,14 @@ _nss_dns_gethostbyaddr2_r (const void *addr, socklen_t len, int af,
     }
 
   n = __libc_res_nquery (&_res, qbuf, C_IN, T_PTR, host_buffer.buf->buf,
-			 1024, &host_buffer.ptr);
+			 1024, &host_buffer.ptr, NULL, NULL);
   if (n < 0 && af == AF_INET6 && (_res.options & RES_NOIP6DOTINT) == 0)
     {
       strcpy (qp, "ip6.int");
       n = __libc_res_nquery (&_res, qbuf, C_IN, T_PTR, host_buffer.buf->buf,
 			     host_buffer.buf != orig_host_buffer
-			     ? MAXPACKET : 1024, &host_buffer.ptr);
+			     ? MAXPACKET : 1024, &host_buffer.ptr,
+			     NULL, NULL);
     }
   if (n < 0)
     {
@@ -555,7 +631,8 @@ getanswer_r (const querybuf *answer, int anslen, const char *qname, int qtype,
   if (n > 0 && bp[0] == '.')
     bp[0] = '\0';
 
-  if (n < 0 || (*name_ok) (bp) == 0)
+  if (__builtin_expect (n < 0 || ((*name_ok) (bp) == 0 && (errno = EBADMSG)),
+			0))
     {
       *errnop = errno;
       *h_errnop = NO_RECOVERY;
@@ -629,7 +706,7 @@ getanswer_r (const querybuf *answer, int anslen, const char *qname, int qtype,
 	  continue;			/* XXX - had_error++ ? */
 	}
 
-      if ((qtype ==T_A || qtype == T_AAAA) && type == T_CNAME)
+      if ((qtype == T_A || qtype == T_AAAA) && type == T_CNAME)
 	{
 	  if (ap >= &host_data->aliases[MAX_NR_ALIASES - 1])
 	    continue;
@@ -857,3 +934,245 @@ getanswer_r (const querybuf *answer, int anslen, const char *qname, int qtype,
   return ((qtype == T_A || qtype == T_AAAA) && ap != host_data->aliases
 	   ? NSS_STATUS_NOTFOUND : NSS_STATUS_TRYAGAIN);
 }
+
+
+static enum nss_status
+gaih_getanswer_slice (const querybuf *answer, int anslen, const char *qname,
+		      struct gaih_addrtuple ***patp,
+		      char **bufferp, size_t *buflenp,
+		      int *errnop, int *h_errnop, int32_t *ttlp, int *firstp)
+{
+  char *buffer = *bufferp;
+  size_t buflen = *buflenp;
+
+  struct gaih_addrtuple **pat = *patp;
+  const HEADER *hp = &answer->hdr;
+  int ancount = ntohs (hp->ancount);
+  int qdcount = ntohs (hp->qdcount);
+  const u_char *cp = answer->buf + HFIXEDSZ;
+  const u_char *end_of_message = answer->buf + anslen;
+  if (__builtin_expect (qdcount != 1, 0))
+    {
+      *h_errnop = NO_RECOVERY;
+      return NSS_STATUS_UNAVAIL;
+    }
+
+   u_char packtmp[NS_MAXCDNAME];
+  int n = __ns_name_unpack (answer->buf, end_of_message, cp,
+			    packtmp, sizeof packtmp);
+  /* We unpack the name to check it for validity.  But we do not need
+     it later.  */
+  if (n != -1 && __ns_name_ntop (packtmp, buffer, buflen) == -1)
+    {
+      if (__builtin_expect (errno, 0) == EMSGSIZE)
+	{
+	too_small:
+	  *errnop = ERANGE;
+	  *h_errnop = NETDB_INTERNAL;
+	  return NSS_STATUS_TRYAGAIN;
+	}
+
+      n = -1;
+    }
+
+  if (__builtin_expect (n < 0 || (res_hnok (buffer) == 0
+				  && (errno = EBADMSG)), 0))
+    {
+      *errnop = errno;
+      *h_errnop = NO_RECOVERY;
+      return NSS_STATUS_UNAVAIL;
+    }
+  cp += n + QFIXEDSZ;
+
+  int haveanswer = 0;
+  int had_error = 0;
+  char *canon = NULL;
+  char *h_name = NULL;
+  int h_namelen = 0;
+
+  while (ancount-- > 0 && cp < end_of_message && had_error == 0)
+    {
+      n = __ns_name_unpack (answer->buf, end_of_message, cp,
+			    packtmp, sizeof packtmp);
+      if (n != -1 &&
+	  (h_namelen = __ns_name_ntop (packtmp, buffer, buflen)) == -1)
+	{
+	  if (__builtin_expect (errno, 0) == EMSGSIZE)
+	    goto too_small;
+
+	  n = -1;
+	}
+      if (n < 0 || res_hnok (buffer) == 0)
+	{
+	  ++had_error;
+	  continue;
+	}
+      if (*firstp)
+	{
+	  h_name = buffer;
+	  buffer += h_namelen;
+	  buflen -= h_namelen;
+	}
+
+      cp += n;				/* name */
+      int type = ns_get16 (cp);
+      cp += INT16SZ;			/* type */
+      int class = ns_get16 (cp);
+      cp += INT16SZ;			/* class */
+      int32_t ttl = ns_get32 (cp);
+      cp += INT32SZ;			/* TTL */
+      n = ns_get16 (cp);
+      cp += INT16SZ;			/* len */
+
+      if (class != C_IN)
+	{
+	  cp += n;
+	  continue;
+	}
+
+      if (type == T_CNAME)
+	{
+	  char tbuf[MAXDNAME];
+	  n = dn_expand (answer->buf, end_of_message, cp, tbuf, sizeof tbuf);
+	  if (n < 0 || res_hnok (tbuf) == 0)
+	    {
+	      ++had_error;
+	      continue;
+	    }
+	  cp += n;
+
+	  if (*firstp)
+	    {
+	      /* Reclaim buffer space.  */
+	      if (h_name + h_namelen == buffer)
+		{
+		  buffer = h_name;
+		  buflen += h_namelen;
+		}
+
+	      n = strlen (tbuf) + 1;
+	      if (__builtin_expect (n > buflen, 0))
+		goto too_small;
+	      if (__builtin_expect (n >= MAXHOSTNAMELEN, 0))
+		{
+		  ++had_error;
+		  continue;
+		}
+
+	      canon = buffer;
+	      buffer = __mempcpy (buffer, tbuf, n);
+	      buflen -= n;
+	      h_namelen = 0;
+	    }
+	  continue;
+	}
+      if (__builtin_expect (type == T_SIG, 0)
+	  || __builtin_expect (type == T_KEY, 0)
+	  || __builtin_expect (type == T_NXT, 0)
+	  || __builtin_expect (type == T_PTR, 0))
+	{
+	  /* We don't support DNSSEC yet.  For now, ignore the record
+	     and send a low priority message to syslog.
+
+	     We also don't expect T_PTR messages.  */
+	  syslog (LOG_DEBUG | LOG_AUTH,
+		  "getaddrinfo*.gaih_getanswer: got type \"%s\"",
+		  p_type (type));
+	  cp += n;
+	  continue;
+	}
+      if (type != T_A && type != T_AAAA)
+	abort ();
+
+      if (*pat == NULL)
+	{
+	  uintptr_t pad = (-(uintptr_t) buffer
+			   % __alignof__ (struct gaih_addrtuple));
+	  buffer += pad;
+	  buflen = buflen > pad ? buflen - pad : 0;
+
+	  if (__builtin_expect (buflen < sizeof (struct gaih_addrtuple),
+				0))
+	    {
+	      *errnop = ERANGE;
+	      *h_errnop = NETDB_INTERNAL;
+	      return NSS_STATUS_TRYAGAIN;
+	    }
+
+	  *pat = (struct gaih_addrtuple *) buffer;
+	  buffer += sizeof (struct gaih_addrtuple);
+	  buflen -= sizeof (struct gaih_addrtuple);
+	}
+
+      (*pat)->name = NULL;
+      (*pat)->next = NULL;
+
+      if (*firstp)
+	{
+	  if (ttl != 0 && ttlp != NULL)
+	    *ttlp = ttl;
+
+	  if (canon != NULL)
+	    {
+	      (*pat)->name = canon;
+
+	      /* Reclaim buffer space.  */
+	      if (h_name + h_namelen == buffer)
+		{
+		  buffer = h_name;
+		  buflen += h_namelen;
+		}
+	    }
+	  else
+	    (*pat)->name = h_name;
+
+	  *firstp = 0;
+	}
+
+      (*pat)->family = type == T_A ? AF_INET : AF_INET6;
+      memcpy ((*pat)->addr, cp, n);
+      cp += n;
+      (*pat)->scopeid = 0;
+
+      pat = &((*pat)->next);
+
+      haveanswer = 1;
+    }
+
+  if (haveanswer)
+    {
+      *patp = pat;
+      *bufferp = buffer;
+      *buflenp = buflen;
+
+      *h_errnop = NETDB_SUCCESS;
+      return NSS_STATUS_SUCCESS;
+    }
+
+  /* Special case here: if the resolver sent a result but it only
+     contains a CNAME while we are looking for a T_A or T_AAAA record,
+     we fail with NOTFOUND instead of TRYAGAIN.  */
+  return canon == NULL ? NSS_STATUS_TRYAGAIN : NSS_STATUS_NOTFOUND;
+}
+
+
+static enum nss_status
+gaih_getanswer (const querybuf *answer1, int anslen1, const querybuf *answer2,
+		int anslen2, const char *qname,
+		struct gaih_addrtuple **pat, char *buffer, size_t buflen,
+		int *errnop, int *h_errnop, int32_t *ttlp)
+{
+  int first = 1;
+
+  enum nss_status status = gaih_getanswer_slice(answer1, anslen1, qname,
+						&pat, &buffer, &buflen,
+						errnop, h_errnop, ttlp,
+						&first);
+  if ((status == NSS_STATUS_SUCCESS || status == NSS_STATUS_NOTFOUND)
+      && answer2 != NULL)
+    status = gaih_getanswer_slice(answer2, anslen2, qname,
+				  &pat, &buffer, &buflen,
+				  errnop, h_errnop, ttlp, &first);
+
+  return status;
+}
diff --git a/resolv/nss_dns/dns-network.c b/resolv/nss_dns/dns-network.c
index 4552b5b678..40736fbe94 100644
--- a/resolv/nss_dns/dns-network.c
+++ b/resolv/nss_dns/dns-network.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1996, 1997, 1998, 1999, 2002, 2004, 2007
+/* Copyright (C) 1996, 1997, 1998, 1999, 2002, 2004, 2007, 2008
    Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Extended from original form by Ulrich Drepper <drepper@cygnus.com>, 1996.
@@ -130,7 +130,7 @@ _nss_dns_getnetbyname_r (const char *name, struct netent *result,
   net_buffer.buf = orig_net_buffer = (querybuf *) alloca (1024);
 
   anslen = __libc_res_nsearch (&_res, qbuf, C_IN, T_PTR, net_buffer.buf->buf,
-			       1024, &net_buffer.ptr);
+			       1024, &net_buffer.ptr, NULL, NULL);
   if (anslen < 0)
     {
       /* Nothing found.  */
@@ -206,7 +206,7 @@ _nss_dns_getnetbyaddr_r (uint32_t net, int type, struct netent *result,
   net_buffer.buf = orig_net_buffer = (querybuf *) alloca (1024);
 
   anslen = __libc_res_nquery (&_res, qbuf, C_IN, T_PTR, net_buffer.buf->buf,
-			      1024, &net_buffer.ptr);
+			      1024, &net_buffer.ptr, NULL, NULL);
   if (anslen < 0)
     {
       /* Nothing found.  */
diff --git a/resolv/res_query.c b/resolv/res_query.c
index 4371af5b05..a8e8d7b739 100644
--- a/resolv/res_query.c
+++ b/resolv/res_query.c
@@ -97,7 +97,7 @@ static const char rcsid[] = "$BINDId: res_query.c,v 8.20 2000/02/29 05:39:12 vix
 static int
 __libc_res_nquerydomain(res_state statp, const char *name, const char *domain,
 			int class, int type, u_char *answer, int anslen,
-			u_char **answerp);
+			u_char **answerp, u_char **answerp2, int *nanswerp2);
 
 /*
  * Formulate a normal query, send, and await answer.
@@ -115,15 +115,20 @@ __libc_res_nquery(res_state statp,
 		  int class, int type,	/* class and type of query */
 		  u_char *answer,	/* buffer to put answer */
 		  int anslen,		/* size of answer buffer */
-		  u_char **answerp)	/* if buffer needs to be enlarged */
+		  u_char **answerp,	/* if buffer needs to be enlarged */
+		  u_char **answerp2,
+		  int *nanswerp2)
 {
-	u_char *buf;
 	HEADER *hp = (HEADER *) answer;
 	int n, use_malloc = 0;
         u_int oflags = statp->_flags;
 
-	size_t bufsize = QUERYSIZE;
-	buf = alloca (bufsize);
+	size_t bufsize = (type == T_UNSPEC ? 2 : 1) * QUERYSIZE;
+	u_char *buf = alloca (bufsize);
+	u_char *query1 = buf;
+	int nquery1 = -1;
+	u_char *query2 = NULL;
+	int nquery2 = 0;
 
  again:
 	hp->rcode = NOERROR;	/* default */
@@ -133,18 +138,47 @@ __libc_res_nquery(res_state statp,
 		printf(";; res_query(%s, %d, %d)\n", name, class, type);
 #endif
 
-	n = res_nmkquery(statp, QUERY, name, class, type, NULL, 0, NULL,
-			 buf, bufsize);
-	if (n > 0
-	    && (oflags & RES_F_EDNS0ERR) == 0
-	    && (statp->options & RES_USE_EDNS0) != 0)
-		n = __res_nopt(statp, n, buf, bufsize, anslen);
+	if (type == T_UNSPEC)
+	  {
+	    n = res_nmkquery(statp, QUERY, name, class, T_A, NULL, 0, NULL,
+			     query1, bufsize);
+	    if (n > 0)
+	      {
+		if ((oflags & RES_F_EDNS0ERR) == 0
+		    && (statp->options & RES_USE_EDNS0) != 0)
+		  n = __res_nopt(statp, n, query1, bufsize, anslen / 2);
+
+		nquery1 = n;
+		query2 = buf + nquery1;
+		n = res_nmkquery(statp, QUERY, name, class, T_AAAA, NULL, 0,
+				 NULL, query2, bufsize - n);
+		if (n > 0
+		    && (oflags & RES_F_EDNS0ERR) == 0
+		    && (statp->options & RES_USE_EDNS0) != 0)
+		  n = __res_nopt(statp, n, query2, bufsize - n, anslen / 2);
+		nquery2 = n;
+	      }
+	  }
+	else
+	  {
+	    n = res_nmkquery(statp, QUERY, name, class, type, NULL, 0, NULL,
+			     query1, bufsize);
+
+	    if (n > 0
+		&& (oflags & RES_F_EDNS0ERR) == 0
+		&& (statp->options & RES_USE_EDNS0) != 0)
+	      n = __res_nopt(statp, n, query1, bufsize, anslen);
+
+	    nquery1 = n;
+	  }
+
 	if (__builtin_expect (n <= 0, 0) && !use_malloc) {
 		/* Retry just in case res_nmkquery failed because of too
 		   short buffer.  Shouldn't happen.  */
-		bufsize = MAXPACKET;
+		bufsize = (type == T_UNSPEC ? 2 : 1) * MAXPACKET;
 		buf = malloc (bufsize);
 		if (buf != NULL) {
+			query1 = buf;
 			use_malloc = 1;
 			goto again;
 		}
@@ -168,7 +202,8 @@ __libc_res_nquery(res_state statp,
 		return (n);
 	}
 	assert (answerp == NULL || (void *) *answerp == (void *) answer);
-	n = __libc_res_nsend(statp, buf, n, answer, anslen, answerp);
+	n = __libc_res_nsend(statp, query1, nquery1, query2, nquery2, answer,
+			     anslen, answerp, answerp2, nanswerp2);
 	if (use_malloc)
 		free (buf);
 	if (n < 0) {
@@ -184,20 +219,37 @@ __libc_res_nquery(res_state statp,
 	  /* __libc_res_nsend might have reallocated the buffer.  */
 	  hp = (HEADER *) *answerp;
 
-	if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) {
+	/* We simplify the following tests by assigning HP to HP2.  It
+	   is easy to verify that this is the same as ignoring all
+	   tests of HP2.  */
+	HEADER *hp2 = answerp2 ? (HEADER *) *answerp2 : hp;
+
+	if ((hp->rcode != NOERROR || ntohs(hp->ancount) == 0)
+	    && (hp2->rcode != NOERROR || ntohs(hp2->ancount) == 0)) {
 #ifdef DEBUG
-		if (statp->options & RES_DEBUG)
+		if (statp->options & RES_DEBUG) {
 			printf(";; rcode = %d, ancount=%d\n", hp->rcode,
 			    ntohs(hp->ancount));
+			if (hp != hp2)
+			  printf(";; rcode2 = %d, ancount2=%d\n", hp2->rcode,
+				 ntohs(hp2->ancount));
+		}
 #endif
-		switch (hp->rcode) {
+		switch (hp->rcode == NOERROR ? hp2->rcode : hp->rcode) {
 		case NXDOMAIN:
+			if ((hp->rcode == NOERROR && ntohs (hp->ancount) != 0)
+			    || (hp2->rcode == NOERROR
+				&& ntohs (hp2->ancount) != 0))
+				goto success;
 			RES_SET_H_ERRNO(statp, HOST_NOT_FOUND);
 			break;
 		case SERVFAIL:
 			RES_SET_H_ERRNO(statp, TRY_AGAIN);
 			break;
 		case NOERROR:
+			if (ntohs (hp->ancount) != 0
+			    || ntohs (hp2->ancount) != 0)
+				goto success;
 			RES_SET_H_ERRNO(statp, NO_DATA);
 			break;
 		case FORMERR:
@@ -209,6 +261,7 @@ __libc_res_nquery(res_state statp,
 		}
 		return (-1);
 	}
+ success:
 	return (n);
 }
 libresolv_hidden_def (__libc_res_nquery)
@@ -221,7 +274,7 @@ res_nquery(res_state statp,
 	   int anslen)		/* size of answer buffer */
 {
 	return __libc_res_nquery(statp, name, class, type, answer, anslen,
-				 NULL);
+				 NULL, NULL, NULL);
 }
 libresolv_hidden_def (res_nquery)
 
@@ -233,11 +286,13 @@ libresolv_hidden_def (res_nquery)
  */
 int
 __libc_res_nsearch(res_state statp,
-	    const char *name,	/* domain name */
-	    int class, int type,	/* class and type of query */
-	    u_char *answer,	/* buffer to put answer */
-	    int anslen,		/* size of answer */
-	    u_char **answerp)
+		   const char *name,	/* domain name */
+		   int class, int type,	/* class and type of query */
+		   u_char *answer,	/* buffer to put answer */
+		   int anslen,		/* size of answer */
+		   u_char **answerp,
+		   u_char **answerp2,
+		   int *nanswerp2)
 {
 	const char *cp, * const *domain;
 	HEADER *hp = (HEADER *) answer;
@@ -260,7 +315,8 @@ __libc_res_nsearch(res_state statp,
 	/* If there aren't any dots, it could be a user-level alias. */
 	if (!dots && (cp = res_hostalias(statp, name, tmp, sizeof tmp))!= NULL)
 		return (__libc_res_nquery(statp, cp, class, type, answer,
-					  anslen, answerp));
+					  anslen, answerp, answerp2,
+					  nanswerp2));
 
 #ifdef DEBUG
 	if (statp->options & RES_DEBUG)
@@ -276,7 +332,8 @@ __libc_res_nsearch(res_state statp,
 	saved_herrno = -1;
 	if (dots >= statp->ndots || trailing_dot) {
 		ret = __libc_res_nquerydomain(statp, name, NULL, class, type,
-					      answer, anslen, answerp);
+					      answer, anslen, answerp,
+					      answerp2, nanswerp2);
 		if (ret > 0 || trailing_dot)
 			return (ret);
 		saved_herrno = h_errno;
@@ -285,6 +342,12 @@ __libc_res_nsearch(res_state statp,
 			answer = *answerp;
 			anslen = MAXPACKET;
 		}
+		if (answerp2
+		    && (*answerp2 < answer || *answerp2 >= answer + anslen))
+		  {
+		    free (*answerp2);
+		    *answerp2 = NULL;
+		  }
 	}
 
 	/*
@@ -307,7 +370,8 @@ __libc_res_nsearch(res_state statp,
 
 			ret = __libc_res_nquerydomain(statp, name, *domain,
 						      class, type,
-						      answer, anslen, answerp);
+						      answer, anslen, answerp,
+						      answerp2, nanswerp2);
 			if (ret > 0)
 				return (ret);
 
@@ -315,6 +379,13 @@ __libc_res_nsearch(res_state statp,
 				answer = *answerp;
 				anslen = MAXPACKET;
 			}
+			if (answerp2
+			    && (*answerp2 < answer
+				|| *answerp2 >= answer + anslen))
+			  {
+			    free (*answerp2);
+			    *answerp2 = NULL;
+			  }
 
 			/*
 			 * If no server present, give up.
@@ -368,7 +439,8 @@ __libc_res_nsearch(res_state statp,
 	 */
 	if (dots && !(tried_as_is || root_on_list)) {
 		ret = __libc_res_nquerydomain(statp, name, NULL, class, type,
-					      answer, anslen, answerp);
+					      answer, anslen, answerp,
+					      answerp2, nanswerp2);
 		if (ret > 0)
 			return (ret);
 	}
@@ -380,6 +452,11 @@ __libc_res_nsearch(res_state statp,
 	 * else send back meaningless H_ERRNO, that being the one from
 	 * the last DNSRCH we did.
 	 */
+	if (answerp2 && (*answerp2 < answer || *answerp2 >= answer + anslen))
+	  {
+	    free (*answerp2);
+	    *answerp2 = NULL;
+	  }
 	if (saved_herrno != -1)
 		RES_SET_H_ERRNO(statp, saved_herrno);
 	else if (got_nodata)
@@ -398,7 +475,7 @@ res_nsearch(res_state statp,
 	    int anslen)		/* size of answer */
 {
 	return __libc_res_nsearch(statp, name, class, type, answer,
-				  anslen, NULL);
+				  anslen, NULL, NULL, NULL);
 }
 libresolv_hidden_def (res_nsearch)
 
@@ -408,12 +485,14 @@ libresolv_hidden_def (res_nsearch)
  */
 static int
 __libc_res_nquerydomain(res_state statp,
-	    const char *name,
-	    const char *domain,
-	    int class, int type,	/* class and type of query */
-	    u_char *answer,		/* buffer to put answer */
-	    int anslen,			/* size of answer */
-	    u_char **answerp)
+			const char *name,
+			const char *domain,
+			int class, int type,	/* class and type of query */
+			u_char *answer,		/* buffer to put answer */
+			int anslen,			/* size of answer */
+			u_char **answerp,
+			u_char **answerp2,
+			int *nanswerp2)
 {
 	char nbuf[MAXDNAME];
 	const char *longname = nbuf;
@@ -450,7 +529,7 @@ __libc_res_nquerydomain(res_state statp,
 		sprintf(nbuf, "%s.%s", name, domain);
 	}
 	return (__libc_res_nquery(statp, longname, class, type, answer,
-				  anslen, answerp));
+				  anslen, answerp, answerp2, nanswerp2));
 }
 
 int
@@ -462,7 +541,7 @@ res_nquerydomain(res_state statp,
 	    int anslen)		/* size of answer */
 {
 	return __libc_res_nquerydomain(statp, name, domain, class, type,
-				       answer, anslen, NULL);
+				       answer, anslen, NULL, NULL, NULL);
 }
 libresolv_hidden_def (res_nquerydomain)
 
diff --git a/resolv/res_send.c b/resolv/res_send.c
index 23306a2fb4..b3dbd702a2 100644
--- a/resolv/res_send.c
+++ b/resolv/res_send.c
@@ -176,10 +176,14 @@ evNowTime(struct timespec *res) {
 /* Forward. */
 
 static int		send_vc(res_state, const u_char *, int,
-				u_char **, int *, int *, int, u_char **);
+				const u_char *, int,
+				u_char **, int *, int *, int, u_char **,
+				u_char **, int *, int *);
 static int		send_dg(res_state, const u_char *, int,
+				const u_char *, int,
 				u_char **, int *, int *, int,
-				int *, int *, u_char **);
+				int *, int *, u_char **,
+				u_char **, int *, int *);
 #ifdef DEBUG
 static void		Aerror(const res_state, FILE *, const char *, int,
 			       const struct sockaddr *);
@@ -334,33 +338,41 @@ libresolv_hidden_def (res_queriesmatch)
 
 int
 __libc_res_nsend(res_state statp, const u_char *buf, int buflen,
-		 u_char *ans, int anssiz, u_char **ansp)
+		 const u_char *buf2, int buflen2,
+		 u_char *ans, int anssiz, u_char **ansp, u_char **ansp2,
+		 int *nansp2)
 {
-	int gotsomewhere, terrno, try, v_circuit, resplen, ns, n;
+  int gotsomewhere, terrno, try, v_circuit, resplen, resplen2, ns, n;
 
 	if (statp->nscount == 0) {
 		__set_errno (ESRCH);
 		return (-1);
 	}
 
-	if (anssiz < HFIXEDSZ) {
+	if (anssiz < (buf2 == NULL ? 1 : 2) * HFIXEDSZ) {
 		__set_errno (EINVAL);
 		return (-1);
 	}
 
-	if ((statp->qhook || statp->rhook) && anssiz < MAXPACKET && ansp) {
-		u_char *buf = malloc (MAXPACKET);
-		if (buf == NULL)
-			return (-1);
-		memcpy (buf, ans, HFIXEDSZ);
-		*ansp = buf;
-		ans = buf;
-		anssiz = MAXPACKET;
+#ifdef USE_HOOKS
+	if (__builtin_expect (statp->qhook || statp->rhook, 0)) {
+		if (anssiz < MAXPACKET && ansp) {
+			u_char *buf = malloc (MAXPACKET);
+			if (buf == NULL)
+				return (-1);
+			memcpy (buf, ans, HFIXEDSZ);
+			*ansp = buf;
+			ans = buf;
+			anssiz = MAXPACKET;
+		}
 	}
+#endif
 
 	DprintQ((statp->options & RES_DEBUG) || (statp->pfcode & RES_PRF_QUERY),
 		(stdout, ";; res_send()\n"), buf, buflen);
-	v_circuit = (statp->options & RES_USEVC) || buflen > PACKETSZ;
+	v_circuit = ((statp->options & RES_USEVC)
+		     || buflen > PACKETSZ
+		     || buflen2 > PACKETSZ);
 	gotsomewhere = 0;
 	terrno = ETIMEDOUT;
 
@@ -442,7 +454,7 @@ __libc_res_nsend(res_state statp, const u_char *buf, int buflen,
 	 * Some resolvers want to even out the load on their nameservers.
 	 * Note that RES_BLAST overrides RES_ROTATE.
 	 */
-	if ((statp->options & RES_ROTATE) != 0 &&
+	if (__builtin_expect ((statp->options & RES_ROTATE) != 0, 0) &&
 	    (statp->options & RES_BLAST) == 0) {
 		struct sockaddr_in6 *ina;
 		unsigned int map;
@@ -479,8 +491,9 @@ __libc_res_nsend(res_state statp, const u_char *buf, int buflen,
 
 		if (nsap == NULL)
 			goto next_ns;
- same_ns:
-		if (statp->qhook) {
+	    same_ns:
+#ifdef USE_HOOKS
+		if (__builtin_expect (statp->qhook != NULL, 0)) {
 			int done = 0, loops = 0;
 
 			do {
@@ -512,6 +525,7 @@ __libc_res_nsend(res_state statp, const u_char *buf, int buflen,
 				}
 			} while (!done);
 		}
+#endif
 
 #ifdef DEBUG
 		char tmpbuf[40];
@@ -521,29 +535,34 @@ __libc_res_nsend(res_state statp, const u_char *buf, int buflen,
 			ns + 1, inet_ntop(AF_INET6, &nsap->sin6_addr,
 					  tmpbuf, sizeof (tmpbuf))));
 
-		if (v_circuit) {
+		if (__builtin_expect (v_circuit, 0)) {
 			/* Use VC; at most one attempt per server. */
 			try = statp->retry;
-			n = send_vc(statp, buf, buflen, &ans, &anssiz, &terrno,
-				    ns, ansp);
+			n = send_vc(statp, buf, buflen, buf2, buflen2,
+				    &ans, &anssiz, &terrno,
+				    ns, ansp, ansp2, nansp2, &resplen2);
 			if (n < 0)
 				return (-1);
 			if (n == 0)
 				goto next_ns;
-			resplen = n;
 		} else {
 			/* Use datagrams. */
-			n = send_dg(statp, buf, buflen, &ans, &anssiz, &terrno,
-				    ns, &v_circuit, &gotsomewhere, ansp);
+			n = send_dg(statp, buf, buflen, buf2, buflen2,
+				    &ans, &anssiz, &terrno,
+				    ns, &v_circuit, &gotsomewhere, ansp,
+				    ansp2, nansp2, &resplen2);
 			if (n < 0)
 				return (-1);
 			if (n == 0)
 				goto next_ns;
 			if (v_circuit)
+			  // XXX Check whether both requests failed or
+			  // XXX whether one have been answered successfully
 				goto same_ns;
-			resplen = n;
 		}
 
+		resplen = n;
+
 		Dprint((statp->options & RES_DEBUG) ||
 		       ((statp->pfcode & RES_PRF_REPLY) &&
 			(statp->pfcode & RES_PRF_HEAD1)),
@@ -553,6 +572,11 @@ __libc_res_nsend(res_state statp, const u_char *buf, int buflen,
 			(statp->pfcode & RES_PRF_REPLY),
 			(stdout, "%s", ""),
 			ans, (resplen > anssiz) ? anssiz : resplen);
+		if (buf2 != NULL)
+		  DprintQ((statp->options & RES_DEBUG) ||
+			  (statp->pfcode & RES_PRF_REPLY),
+			  (stdout, "%s", ""),
+			  *ansp2, (resplen2 > *nansp2) ? *nansp2 : resplen2);
 
 		/*
 		 * If we have temporarily opened a virtual circuit,
@@ -563,7 +587,8 @@ __libc_res_nsend(res_state statp, const u_char *buf, int buflen,
 		    (statp->options & RES_STAYOPEN) == 0) {
 			__res_iclose(statp, false);
 		}
-		if (statp->rhook) {
+#ifdef USE_HOOKS
+		if (__builtin_expect (statp->rhook, 0)) {
 			int done = 0, loops = 0;
 
 			do {
@@ -593,6 +618,7 @@ __libc_res_nsend(res_state statp, const u_char *buf, int buflen,
 			} while (!done);
 
 		}
+#endif
 		return (resplen);
  next_ns: ;
 	   } /*foreach ns*/
@@ -612,7 +638,8 @@ int
 res_nsend(res_state statp,
 	  const u_char *buf, int buflen, u_char *ans, int anssiz)
 {
-	return __libc_res_nsend(statp, buf, buflen, ans, anssiz, NULL);
+  return __libc_res_nsend(statp, buf, buflen, NULL, 0, ans, anssiz,
+			  NULL, NULL, NULL);
 }
 libresolv_hidden_def (res_nsend)
 
@@ -620,17 +647,23 @@ libresolv_hidden_def (res_nsend)
 
 static int
 send_vc(res_state statp,
-	const u_char *buf, int buflen, u_char **ansp, int *anssizp,
-	int *terrno, int ns, u_char **anscp)
+	const u_char *buf, int buflen, const u_char *buf2, int buflen2,
+	u_char **ansp, int *anssizp,
+	int *terrno, int ns, u_char **anscp, u_char **ansp2, int *anssizp2,
+	int *resplen2)
 {
 	const HEADER *hp = (HEADER *) buf;
+	const HEADER *hp2 = (HEADER *) buf2;
 	u_char *ans = *ansp;
-	int anssiz = *anssizp;
+	int orig_anssizp = *anssizp;
+	// XXX REMOVE
+	// int anssiz = *anssizp;
 	HEADER *anhp = (HEADER *) ans;
 	struct sockaddr_in6 *nsap = EXT(statp).nsaddrs[ns];
 	int truncating, connreset, resplen, n;
-	struct iovec iov[2];
+	struct iovec iov[4];
 	u_short len;
+	u_short len2;
 	u_char *cp;
 
 	connreset = 0;
@@ -677,11 +710,19 @@ send_vc(res_state statp,
 	/*
 	 * Send length & message
 	 */
-	ns_put16((u_short)buflen, (u_char*)&len);
+	len = htons ((u_short) buflen);
 	evConsIovec(&len, INT16SZ, &iov[0]);
 	evConsIovec((void*)buf, buflen, &iov[1]);
-	if (TEMP_FAILURE_RETRY (writev(statp->_vcsock, iov, 2))
-	    != (INT16SZ + buflen)) {
+	int niov = 2;
+	ssize_t explen = INT16SZ + buflen;
+	if (buf2 != NULL) {
+		len2 = htons ((u_short) buflen2);
+		evConsIovec(&len2, INT16SZ, &iov[2]);
+		evConsIovec((void*)buf2, buflen2, &iov[3]);
+		niov = 4;
+		explen += INT16SZ + buflen2;
+	}
+	if (TEMP_FAILURE_RETRY (writev(statp->_vcsock, iov, niov)) != explen) {
 		*terrno = errno;
 		Perror(statp, stderr, "write failed", errno);
 		__res_iclose(statp, false);
@@ -690,6 +731,8 @@ send_vc(res_state statp,
 	/*
 	 * Receive length & response
 	 */
+	int recvresp1 = 0;
+	int recvresp2 = buf2 == NULL;
  read_len:
 	cp = ans;
 	len = INT16SZ;
@@ -718,30 +761,66 @@ send_vc(res_state statp,
 		}
 		return (0);
 	}
+#ifdef _STRING_ARCH_unaligned
+	resplen = ntohs (*(uint16_t *) ans);
+#else
 	resplen = ns_get16(ans);
-	if (resplen > anssiz) {
+#endif
+
+	int *thisanssizp;
+	u_char **thisansp;
+	int *thisresplenp;
+	if ((recvresp1 | recvresp2) == 0 || buf2 == NULL) {
+		thisanssizp = anssizp;
+		thisansp = anscp ?: ansp;
+		assert (anscp != NULL || ansp2 == NULL);
+		thisresplenp = &resplen;
+	} else {
+		if (*anssizp != MAXPACKET) {
+			/* No buffer allocated for the first
+			   reply.  We can try to use the rest
+			   of the user-provided buffer.  */
+			*anssizp2 = orig_anssizp - resplen;
+			*ansp2 = *ansp + resplen;
+		} else {
+			/* The first reply did not fit into the
+			   user-provided buffer.  Maybe the second
+			   answer will.  */
+			*anssizp2 = orig_anssizp;
+			*ansp2 = *ansp;
+		}
+
+		thisanssizp = anssizp2;
+		thisansp = ansp2;
+		thisresplenp = resplen2;
+	}
+	anhp = (HEADER *) *thisansp;
+
+	*thisresplenp = resplen;
+	if (resplen > *thisanssizp) {
+		/* Yes, we test ANSCP here.  If we have two buffers
+		   both will be allocatable.  */
 		if (anscp) {
-			ans = malloc (MAXPACKET);
-			if (ans == NULL) {
+			u_char *newp = malloc (MAXPACKET);
+			if (newp == NULL) {
 				*terrno = ENOMEM;
 				__res_iclose(statp, false);
 				return (0);
 			}
-			anssiz = MAXPACKET;
-			*anssizp = MAXPACKET;
-			*ansp = ans;
-			*anscp = ans;
-			anhp = (HEADER *) ans;
+			*thisanssizp = MAXPACKET;
+			*thisansp = newp;
+			anhp = (HEADER *) newp;
 			len = resplen;
 		} else {
 			Dprint(statp->options & RES_DEBUG,
 				(stdout, ";; response truncated\n")
 			);
 			truncating = 1;
-			len = anssiz;
+			len = *thisanssizp;
 		}
 	} else
 		len = resplen;
+
 	if (len < HFIXEDSZ) {
 		/*
 		 * Undersized message.
@@ -752,7 +831,8 @@ send_vc(res_state statp,
 		__res_iclose(statp, false);
 		return (0);
 	}
-	cp = ans;
+
+	cp = *thisansp;
 	while (len != 0 && (n = read(statp->_vcsock, (char *)cp, (int)len)) > 0){
 		cp += n;
 		len -= n;
@@ -768,7 +848,7 @@ send_vc(res_state statp,
 		 * Flush rest of answer so connection stays in synch.
 		 */
 		anhp->tc = 1;
-		len = resplen - anssiz;
+		len = resplen - *thisanssizp;
 		while (len != 0) {
 			char junk[PACKETSZ];
 
@@ -787,14 +867,25 @@ send_vc(res_state statp,
 	 * itself confused, then drop the packet and
 	 * wait for the correct one.
 	 */
-	if (hp->id != anhp->id) {
+	if ((recvresp1 || hp->id != anhp->id)
+	    && (recvresp2 || hp2->id != anhp->id)) {
 		DprintQ((statp->options & RES_DEBUG) ||
 			(statp->pfcode & RES_PRF_REPLY),
 			(stdout, ";; old answer (unexpected):\n"),
-			ans, (resplen > anssiz) ? anssiz: resplen);
+			*thisansp,
+			(resplen > *thisanssiz) ? *thisanssiz: resplen);
 		goto read_len;
 	}
 
+	/* Mark which reply we received.  */
+	if (recvresp1 == 0 && hp->id == anhp->id)
+	  recvresp1 = 1;
+	else
+	  recvresp2 = 1;
+	/* Repeat waiting if we have a second answer to arrive.  */
+	if ((recvresp1 & recvresp2) == 0)
+		goto read_len;
+
 	/*
 	 * All is well, or the error is fatal.  Signal that the
 	 * next nameserver ought not be tried.
@@ -804,19 +895,20 @@ send_vc(res_state statp,
 
 static int
 send_dg(res_state statp,
-	const u_char *buf, int buflen, u_char **ansp, int *anssizp,
-	int *terrno, int ns, int *v_circuit, int *gotsomewhere, u_char **anscp)
+	const u_char *buf, int buflen, const u_char *buf2, int buflen2,
+	u_char **ansp, int *anssizp,
+	int *terrno, int ns, int *v_circuit, int *gotsomewhere, u_char **anscp,
+	u_char **ansp2, int *anssizp2, int *resplen2)
 {
 	const HEADER *hp = (HEADER *) buf;
+	const HEADER *hp2 = (HEADER *) buf2;
 	u_char *ans = *ansp;
-	int anssiz = *anssizp;
-	HEADER *anhp = (HEADER *) ans;
+	int orig_anssizp = *anssizp;
 	struct sockaddr_in6 *nsap = EXT(statp).nsaddrs[ns];
 	struct timespec now, timeout, finish;
 	struct pollfd pfd[1];
         int ptimeout;
 	struct sockaddr_in6 from;
-	socklen_t fromlen;
 	int resplen, seconds, n;
 
 	if (EXT(statp).nssocks[ns] == -1) {
@@ -879,6 +971,8 @@ send_dg(res_state statp,
 	evAddTime(&finish, &now, &timeout);
 	int need_recompute = 0;
 	int nwritten = 0;
+	int recvresp1 = 0;
+	int recvresp2 = buf2 == NULL;
 	pfd[0].fd = EXT(statp).nssocks[ns];
 	pfd[0].events = POLLOUT;
  wait:
@@ -918,35 +1012,73 @@ send_dg(res_state statp,
 	}
 	__set_errno (0);
 	if (pfd[0].revents & POLLOUT) {
-		if (send (pfd[0].fd, buf, buflen, MSG_NOSIGNAL) != buflen) {
+		ssize_t sr;
+		if (nwritten != 0)
+		  sr = send (pfd[0].fd, buf2, buflen2, MSG_NOSIGNAL);
+		else
+		  sr = send (pfd[0].fd, buf, buflen, MSG_NOSIGNAL);
+
+		if (sr != buflen) {
 			if (errno == EINTR || errno == EAGAIN)
 				goto recompute_resend;
 			Perror(statp, stderr, "send", errno);
 			goto err_out;
 		}
-		pfd[0].events = POLLIN;
+		if (nwritten != 0 || buf2 == NULL)
+		  pfd[0].events = POLLIN;
+		else
+		  pfd[0].events = POLLIN | POLLOUT;
 		++nwritten;
 		goto wait;
 	} else if (pfd[0].revents & POLLIN) {
-		fromlen = sizeof(struct sockaddr_in6);
-		if (anssiz < MAXPACKET
+		int *thisanssizp;
+		u_char **thisansp;
+		int *thisresplenp;
+
+		if ((recvresp1 | recvresp2) == 0 || buf2 == NULL) {
+			thisanssizp = anssizp;
+			thisansp = anscp ?: ansp;
+			assert (anscp != NULL || ansp2 == NULL);
+			thisresplenp = &resplen;
+		} else {
+			if (*anssizp != MAXPACKET) {
+				/* No buffer allocated for the first
+				   reply.  We can try to use the rest
+				   of the user-provided buffer.  */
+				*anssizp2 = orig_anssizp - resplen;
+				*ansp2 = *ansp + resplen;
+			} else {
+				/* The first reply did not fit into the
+				   user-provided buffer.  Maybe the second
+				   answer will.  */
+				*anssizp2 = orig_anssizp;
+				*ansp2 = *ansp;
+			}
+
+			thisanssizp = anssizp2;
+			thisansp = ansp2;
+			thisresplenp = resplen2;
+		}
+
+		if (*thisanssizp < MAXPACKET
+		    /* Yes, we test ANSCP here.  If we have two buffers
+		       both will be allocatable.  */
 		    && anscp
-		    && (ioctl (pfd[0].fd, FIONREAD, &resplen) < 0
-		|| anssiz < resplen)) {
-			ans = malloc (MAXPACKET);
-			if (ans == NULL)
-				ans = *ansp;
-			else {
-				anssiz = MAXPACKET;
+		    && (ioctl (pfd[0].fd, FIONREAD, thisresplenp) < 0
+			|| *thisanssizp < *thisresplenp)) {
+			u_char *newp = malloc (MAXPACKET);
+			if (newp != NULL) {
 				*anssizp = MAXPACKET;
-				*ansp = ans;
-				*anscp = ans;
-				anhp = (HEADER *) ans;
+				*thisansp = ans = newp;
 			}
 		}
-		resplen = recvfrom(pfd[0].fd, (char*)ans, anssiz,0,
-				   (struct sockaddr *)&from, &fromlen);
-		if (resplen <= 0) {
+		HEADER *anhp = (HEADER *) *thisansp;
+		socklen_t fromlen = sizeof(struct sockaddr_in6);
+		assert (sizeof(from) <= fromlen);
+		*thisresplenp = recvfrom(pfd[0].fd, (char*)*thisansp,
+					 *thisanssizp, 0,
+					(struct sockaddr *)&from, &fromlen);
+		if (*thisresplenp <= 0) {
 			if (errno == EINTR || errno == EAGAIN) {
 				need_recompute = 1;
 				goto wait;
@@ -955,17 +1087,18 @@ send_dg(res_state statp,
 			goto err_out;
 		}
 		*gotsomewhere = 1;
-		if (resplen < HFIXEDSZ) {
+		if (*thisresplenp < HFIXEDSZ) {
 			/*
 			 * Undersized message.
 			 */
 			Dprint(statp->options & RES_DEBUG,
 			       (stdout, ";; undersized: %d\n",
-				resplen));
+				*thisresplen));
 			*terrno = EMSGSIZE;
 			goto err_out;
 		}
-		if (hp->id != anhp->id) {
+		if ((recvresp1 || hp->id != anhp->id)
+		    && (recvresp2 || hp2->id != anhp->id)) {
 			/*
 			 * response from old query, ignore it.
 			 * XXX - potential security hazard could
@@ -974,7 +1107,9 @@ send_dg(res_state statp,
 			DprintQ((statp->options & RES_DEBUG) ||
 				(statp->pfcode & RES_PRF_REPLY),
 				(stdout, ";; old answer:\n"),
-				ans, (resplen > anssiz) ? anssiz : resplen);
+				thisansp,
+				(*thisresplen > *thisanssiz)
+				? *thisanssiz : *thisresplen);
 			goto wait;
 		}
 		if (!(statp->options & RES_INSECURE1) &&
@@ -987,14 +1122,16 @@ send_dg(res_state statp,
 			DprintQ((statp->options & RES_DEBUG) ||
 				(statp->pfcode & RES_PRF_REPLY),
 				(stdout, ";; not our server:\n"),
-				ans, (resplen > anssiz) ? anssiz : resplen);
+				thisansp,
+				(*thisresplen > *thisanssiz)
+				? *thisanssiz : *thisresplen);
 			goto wait;
 		}
 #ifdef RES_USE_EDNS0
 		if (anhp->rcode == FORMERR
 		    && (statp->options & RES_USE_EDNS0) != 0U) {
 			/*
-			 * Do not retry if the server do not understand
+			 * Do not retry if the server does not understand
 			 * EDNS0.  The case has to be captured here, as
 			 * FORMERR packet do not carry query section, hence
 			 * res_queriesmatch() returns 0.
@@ -1002,15 +1139,23 @@ send_dg(res_state statp,
 			DprintQ(statp->options & RES_DEBUG,
 				(stdout,
 				 "server rejected query with EDNS0:\n"),
-				ans, (resplen > anssiz) ? anssiz : resplen);
+				thisans,
+				(*thisresplen > *thisanssiz)
+				? *thisanssiz : *thisresplen);
 			/* record the error */
 			statp->_flags |= RES_F_EDNS0ERR;
 			goto err_out;
         }
 #endif
-		if (!(statp->options & RES_INSECURE2) &&
-		    !res_queriesmatch(buf, buf + buflen,
-				      ans, ans + anssiz)) {
+		if (!(statp->options & RES_INSECURE2)
+		    && (recvresp1 || !res_queriesmatch(buf, buf + buflen,
+						       *thisansp,
+						       *thisansp
+						       + *thisanssizp))
+		    && (recvresp2 || !res_queriesmatch(buf2, buf2 + buflen2,
+						       *thisansp,
+						       *thisansp
+						       + *thisanssizp))) {
 			/*
 			 * response contains wrong query? ignore it.
 			 * XXX - potential security hazard could
@@ -1019,7 +1164,9 @@ send_dg(res_state statp,
 			DprintQ((statp->options & RES_DEBUG) ||
 				(statp->pfcode & RES_PRF_REPLY),
 				(stdout, ";; wrong query name:\n"),
-				ans, (resplen > anssiz) ? anssiz : resplen);
+				thisansp,
+				(*thisresplen > *thisanssiz)
+				? *thisanssiz : *thisresplen);
 			goto wait;
 		}
 		if (anhp->rcode == SERVFAIL ||
@@ -1027,7 +1174,9 @@ send_dg(res_state statp,
 		    anhp->rcode == REFUSED) {
 			DprintQ(statp->options & RES_DEBUG,
 				(stdout, "server rejected query:\n"),
-				ans, (resplen > anssiz) ? anssiz : resplen);
+				thisansp,
+				(*thisresplen > *thisanssiz)
+				? *thisanssiz : *thisresplen);
 		next_ns:
 			__res_iclose(statp, false);
 			/* don't retry if called from dig */
@@ -1038,7 +1187,9 @@ send_dg(res_state statp,
 		    && anhp->aa == 0 && anhp->ra == 0 && anhp->arcount == 0) {
 			DprintQ(statp->options & RES_DEBUG,
 				(stdout, "referred query:\n"),
-				ans, (resplen > anssiz) ? anssiz : resplen);
+				thisansp,
+				(*thisresplen > *thisanssiz)
+				? *thisanssiz : *thisresplen);
 			goto next_ns;
 		}
 		if (!(statp->options & RES_IGNTC) && anhp->tc) {
@@ -1050,8 +1201,18 @@ send_dg(res_state statp,
 			       (stdout, ";; truncated answer\n"));
 			*v_circuit = 1;
 			__res_iclose(statp, false);
+			// XXX if we have received one reply we could
+			// XXX use it and not repeat it over TCP...
 			return (1);
 		}
+		/* Mark which reply we received.  */
+		if (recvresp1 == 0 && hp->id == anhp->id)
+			recvresp1 = 1;
+		else
+			recvresp2 = 1;
+		/* Repeat waiting if we have a second answer to arrive.  */
+		if ((recvresp1 & recvresp2) == 0)
+			goto wait;
 		/*
 		 * All is well, or the error is fatal.  Signal that the
 		 * next nameserver ought not be tried.
diff --git a/sysdeps/posix/getaddrinfo.c b/sysdeps/posix/getaddrinfo.c
index 9a27efdf83..3de83e3948 100644
--- a/sysdeps/posix/getaddrinfo.c
+++ b/sysdeps/posix/getaddrinfo.c
@@ -40,6 +40,7 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <errno.h>
 #include <ifaddrs.h>
 #include <netdb.h>
+#include <nss.h>
 #include <resolv.h>
 #include <stdbool.h>
 #include <stdio.h>
@@ -91,14 +92,6 @@ struct gaih_servtuple
 
 static const struct gaih_servtuple nullserv;
 
-struct gaih_addrtuple
-  {
-    struct gaih_addrtuple *next;
-    char *name;
-    int family;
-    uint32_t addr[4];
-    uint32_t scopeid;
-  };
 
 struct gaih_typeproto
   {
@@ -202,6 +195,7 @@ gaih_inet_serv (const char *servicename, const struct gaih_typeproto *tp,
       if (herrno == NETDB_INTERNAL)					      \
 	{								      \
 	  __set_h_errno (herrno);					      \
+	  _res.options = old_res_options;				      \
 	  return -EAI_SYSTEM;						      \
 	}								      \
       if (herrno == TRY_AGAIN)						      \
@@ -246,6 +240,10 @@ gaih_inet_serv (const char *servicename, const struct gaih_typeproto *tp,
  }
 
 
+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,
@@ -685,87 +683,132 @@ gaih_inet (const char *name, const struct gaih_service *service,
 
 	  while (!no_more)
 	    {
-	      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)
+	      nss_gethostbyname4_r fct4
+		= __nss_lookup_function (nip, "gethostbyname4_r");
+	      if (fct4 != NULL)
 		{
-		  if (req->ai_family == AF_INET6
-		      || req->ai_family == AF_UNSPEC)
+		  int herrno;
+
+		  while (1)
 		    {
-		      gethosts (AF_INET6, struct in6_addr);
-		      no_inet6_data = no_data;
-		      inet6_status = status;
+		      rc = 0;
+		      status = DL_CALL_FCT (fct4, (name, pat, tmpbuf,
+						   tmpbuflen, &rc, &herrno,
+						   NULL));
+		      if (status != NSS_STATUS_TRYAGAIN
+			  || rc != ERANGE || herrno != NETDB_INTERNAL)
+			{
+			  if (herrno == NETDB_INTERNAL)
+			    {
+			      __set_h_errno (herrno);
+			      _res.options = old_res_options;
+			      return -EAI_SYSTEM;
+			    }
+			  if (herrno == TRY_AGAIN)
+			    no_data = EAI_AGAIN;
+			  else
+			    no_data = herrno == NO_DATA;
+			  break;
+			}
+		      tmpbuf = extend_alloca (tmpbuf,
+					      tmpbuflen, 2 * tmpbuflen);
 		    }
-		  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)))
+
+		  if (status == NSS_STATUS_SUCCESS)
 		    {
-		      gethosts (AF_INET, struct in_addr);
+		      canon = (*pat)->name;
 
-		      if (req->ai_family == AF_INET)
+		      while (*pat != NULL)
+			pat = &((*pat)->next);
+		    }
+		}
+	      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 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)
+		      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)))
 			{
-			  /* If we need the canonical name, get it
-			     from the same service as the result.  */
-			  nss_getcanonname_r cfct;
-			  int herrno;
+			  gethosts (AF_INET, struct in_addr);
 
-			  cfct = __nss_lookup_function (nip, "getcanonname_r");
-			  if (cfct != NULL)
+			  if (req->ai_family == AF_INET)
 			    {
-			      const size_t max_fqdn_len = 256;
-			      char *buf = alloca (max_fqdn_len);
-			      char *s;
-
-			      if (DL_CALL_FCT (cfct, (at->name ?: name, buf,
-						      max_fqdn_len, &s, &rc,
-						      &herrno))
-				  == NSS_STATUS_SUCCESS)
-				canon = s;
-			      else
-				/* Set to name now to avoid using
-				   gethostbyaddr.  */
-				canon = name;
+			      no_inet6_data = no_data;
+			      inet6_status = status;
 			    }
 			}
 
-		      break;
-		    }
+		      /* 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)
+			    {
+			      /* If we need the canonical name, get it
+				 from the same service as the result.  */
+			      nss_getcanonname_r cfct;
+			      int herrno;
+
+			      cfct = __nss_lookup_function (nip,
+							    "getcanonname_r");
+			      if (cfct != NULL)
+				{
+				  const size_t max_fqdn_len = 256;
+				  char *buf = alloca (max_fqdn_len);
+				  char *s;
+
+				  if (DL_CALL_FCT (cfct, (at->name ?: name,
+							  buf, max_fqdn_len,
+							  &s, &rc, &herrno))
+				      == NSS_STATUS_SUCCESS)
+				    canon = s;
+				  else
+				    /* Set to name now to avoid using
+				       gethostbyaddr.  */
+				    canon = name;
+				}
+			    }
 
-		  /* 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;
+			  break;
+			}
+
+		      /* 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;
+		    }
 		}
 
 	      if (nss_next_action (nip, status) == NSS_ACTION_RETURN)