diff mbox series

v3 [PATCH 4/4] nsswitch: use new internal API

Message ID xn1rjsdj6u.fsf@greed.delorie.com
State Superseded
Headers show
Series v3 [PATCH 4/4] nsswitch: use new internal API | expand

Commit Message

DJ Delorie Aug. 27, 2020, 6:42 p.m. UTC
From 4b6ef844fe1ed39e8f9b8ffeb1dae51bdcbff32e Mon Sep 17 00:00:00 2001
From: DJ Delorie <dj@redhat.com>
Date: Tue, 23 Jun 2020 16:49:16 -0400
Subject: [PATCH 4/4] nsswitch: use new internal API

Stitch new ABI and types throughout all NSS callers and providers.
---
 grp/compat-initgroups.c                 |   2 +-
 grp/initgroups.c                        |  41 +-
 inet/ether_hton.c                       |  21 +-
 inet/ether_ntoh.c                       |  21 +-
 inet/getnetgrent_r.c                    |  40 +-
 inet/netgroup.h                         |   2 +-
 malloc/set-freeres.c                    |   4 +-
 nscd/aicache.c                          |  17 +-
 nscd/gai.c                              |   2 +-
 nscd/initgrcache.c                      |   8 +-
 nscd/netgroupcache.c                    |   4 +-
 nscd/nscd_netgroup.c                    |   2 +-
 nss/Makefile                            |   3 +-
 nss/XXX-lookup.c                        |   7 +-
 nss/compat-lookup.c                     |   8 +-
 nss/getXXbyYY_r.c                       |  51 +-
 nss/getXXent_r.c                        |  10 +-
 nss/getnssent_r.c                       |  22 +-
 nss/nss_action.c                        |   2 +-
 nss/nss_action_parse.c                  |  22 +-
 nss/nss_compat/compat-grp.c             |   2 +-
 nss/nss_compat/compat-initgroups.c      |   2 +-
 nss/nss_compat/compat-pwd.c             |   2 +-
 nss/nss_compat/compat-spwd.c            |   2 +-
 nss/nss_database.c                      |  40 +-
 nss/nss_module.c                        |  64 +-
 nss/nss_test.h                          |   9 +
 nss/nss_test1.c                         | 166 ++++-
 nss/nsswitch.c                          | 809 +-----------------------
 nss/nsswitch.h                          |  69 +-
 nss/tst-reload1.c                       | 341 ++++++++++
 nss/tst-reload1.root/etc/nsswitch.conf  |   3 +
 nss/tst-reload1.root/etc/nsswitch.conf2 |   3 +
 nss/tst-reload1.root/etc/services       |   1 +
 nss/tst-reload1.root/tst-reload1.script |   2 +
 posix/tst-rfc3484-2.c                   |   2 +-
 posix/tst-rfc3484-3.c                   |   2 +-
 posix/tst-rfc3484.c                     |   2 +-
 sunrpc/netname.c                        |  21 +-
 sunrpc/publickey.c                      |  42 +-
 sysdeps/posix/getaddrinfo.c             |  19 +-
 41 files changed, 782 insertions(+), 1110 deletions(-)
 create mode 100644 nss/tst-reload1.c
 create mode 100644 nss/tst-reload1.root/etc/nsswitch.conf
 create mode 100644 nss/tst-reload1.root/etc/nsswitch.conf2
 create mode 100644 nss/tst-reload1.root/etc/services
 create mode 100644 nss/tst-reload1.root/tst-reload1.script

Comments

Siddhesh Poyarekar Nov. 4, 2020, 7:30 a.m. UTC | #1
On 8/28/20 12:12 AM, DJ Delorie via Libc-alpha wrote:
> 
>  From 4b6ef844fe1ed39e8f9b8ffeb1dae51bdcbff32e Mon Sep 17 00:00:00 2001
> From: DJ Delorie <dj@redhat.com>
> Date: Tue, 23 Jun 2020 16:49:16 -0400
> Subject: [PATCH 4/4] nsswitch: use new internal API
> 
> Stitch new ABI and types throughout all NSS callers and providers.

Could you split up the mechanical changes, i.e. the stitching of the new 
ABI and the reloading code into separate patches?  The patch is quite 
large and I'm worried I'll miss out on some detail in the review process.

I did a quick run and found that tst-reload1 fails during make-check. 
When run as part of the check, tst-reload1.out has:

error: tst-reload1.c:121: not true: p != NULL
error: tst-reload1.c:121: not true: p != NULL
error: tst-reload1.c:124: not true: strcmp (p->pw_name, pt[i].pw_name) == 0
error: tst-reload1.c:121: not true: p != NULL
error: tst-reload1.c:121: not true: p != NULL
error: tst-reload1.c:135: not true: strcmp (p->pw_name, pt[i].pw_name) == 0
error: tst-reload1.c:136: not true: p->pw_uid == pt[i].pw_uid
error: tst-reload1.c:136: not true: p->pw_uid == pt[i].pw_uid
error: tst-reload1.c:135: not true: strcmp (p->pw_name, pt[i].pw_name) == 0
error: tst-reload1.c:136: not true: p->pw_uid == pt[i].pw_uid
error: tst-reload1.c:132: not true: p != NULL
error: tst-reload1.c:132: not true: p != NULL
error: tst-reload1.c:144: not true: h != NULL
error: tst-reload1.c:144: not true: h != NULL
error: tst-reload1.c:144: not true: h != NULL
Didn't expect signal from child: got `Segmentation fault'

Also, git-am reported a couple of whitespace warnings, one of them is 
this and the other is in tst-reload1.c.

> +  for (size_t idx = 0; idx < nhost_data; ++idx)
> +    if (memcmp (host_data[idx].h_addr, addr, len) == 0)
> +      return copy_host (result, & host_data[idx], buffer, buflen, h_errnop);
> +	

Trailing whitespace here.

> +  return NSS_STATUS_NOTFOUND;
> +}
> +
> +/* Note: only the first address is supported, intentionally.  */
> +enum nss_status
> +NAME(gethostbyaddr_r) (const void *addr, socklen_t len, int af,
> +		       struct hostent *result, char *buffer, size_t buflen,
> +		       int *errnop, int *h_errnop)
> +{
> +  return NAME(gethostbyaddr2_r) (addr, len, af, result, buffer, buflen,
> +				 errnop, h_errnop, NULL);
> +}
> diff --git a/nss/nsswitch.c b/nss/nsswitch.c
> index 8d7b69d4bc..9b73296c5f 100644
> --- a/nss/nsswitch.c
> +++ b/nss/nsswitch.c

A lot of these changes along with the bits in nss_module.c to add 
monitoring could become a separate patch to replace legacy parsing with 
the infrastructure implemented in 1-3/4.  The mechanical changes could 
then be a separate change.  That way the actual stitching bits could get 
closer review focus given that they're not mixed in with the mechanical 
changes.

Thanks,
Siddhesh
diff mbox series

Patch

diff --git a/grp/compat-initgroups.c b/grp/compat-initgroups.c
index 3dd50d2306..9df940767b 100644
--- a/grp/compat-initgroups.c
+++ b/grp/compat-initgroups.c
@@ -10,7 +10,7 @@  typedef enum nss_status (*get_function) (struct group *, char *,
 
 
 static enum nss_status
-compat_call (service_user *nip, const char *user, gid_t group, long int *start,
+compat_call (nss_action_list nip, const char *user, gid_t group, long int *start,
 	     long int *size, gid_t **groupsp, long int limit, int *errnop)
 {
   struct group grpbuf;
diff --git a/grp/initgroups.c b/grp/initgroups.c
index 0c17141117..6fd8e85517 100644
--- a/grp/initgroups.c
+++ b/grp/initgroups.c
@@ -63,7 +63,6 @@  internal_getgrouplist (const char *user, gid_t group, long int *size,
 #endif
 
   enum nss_status status = NSS_STATUS_UNAVAIL;
-  int no_more = 0;
 
   /* Never store more than the starting *SIZE number of elements.  */
   assert (*size > 0);
@@ -71,33 +70,28 @@  internal_getgrouplist (const char *user, gid_t group, long int *size,
   /* Start is one, because we have the first group as parameter.  */
   long int start = 1;
 
-  if (__nss_initgroups_database == NULL)
-    {
-      if (__nss_database_lookup2 ("initgroups", NULL, "",
-				  &__nss_initgroups_database) < 0)
-	{
-	  if (__nss_group_database == NULL)
-	    no_more = __nss_database_lookup2 ("group", NULL, "files",
-					      &__nss_group_database);
+  nss_action_list nip;
 
-	  __nss_initgroups_database = __nss_group_database;
-	}
-      else
-	use_initgroups_entry = true;
+  if (__nss_database_get (nss_database_initgroups, &nip))
+    {
+      use_initgroups_entry = true;
+    }
+  else if (__nss_database_get (nss_database_group, &nip))
+    {
+      use_initgroups_entry = false;
     }
   else
-    /* __nss_initgroups_database might have been set through
-       __nss_configure_lookup in which case use_initgroups_entry was
-       not set here.  */
-    use_initgroups_entry = __nss_initgroups_database != __nss_group_database;
+    {
+      nip = __nss_action_parse ("files");
+      use_initgroups_entry = false;
+    }
 
-  service_user *nip = __nss_initgroups_database;
-  while (! no_more)
+  while (nip && nip->module)
     {
       long int prev_start = start;
 
-      initgroups_dyn_function fct = __nss_lookup_function (nip,
-							   "initgroups_dyn");
+      initgroups_dyn_function fct = __nss_lookup_function (nip, "initgroups_dyn");
+
       if (fct == NULL)
 	status = compat_call (nip, user, group, &start, size, groupsp,
 			      limit, &errno);
@@ -134,10 +128,7 @@  internal_getgrouplist (const char *user, gid_t group, long int *size,
 	  && nss_next_action (nip, status) == NSS_ACTION_RETURN)
 	 break;
 
-      if (nip->next == NULL)
-	no_more = -1;
-      else
-	nip = nip->next;
+      nip ++;
     }
 
   return start;
diff --git a/inet/ether_hton.c b/inet/ether_hton.c
index ff6943fc35..cccae17f10 100644
--- a/inet/ether_hton.c
+++ b/inet/ether_hton.c
@@ -30,9 +30,7 @@  typedef int (*lookup_function) (const char *, struct etherent *, char *, int,
 int
 ether_hostton (const char *hostname, struct ether_addr *addr)
 {
-  static service_user *startp;
-  static lookup_function start_fct;
-  service_user *nip;
+  nss_action_list nip;
   union
   {
     lookup_function f;
@@ -42,22 +40,7 @@  ether_hostton (const char *hostname, struct ether_addr *addr)
   enum nss_status status = NSS_STATUS_UNAVAIL;
   struct etherent etherent;
 
-  if (startp == NULL)
-    {
-      no_more = __nss_ethers_lookup2 (&nip, "gethostton_r", NULL, &fct.ptr);
-      if (no_more)
-	startp = (service_user *) -1;
-      else
-	{
-	  startp = nip;
-	  start_fct = fct.f;
-	}
-    }
-  else
-    {
-      fct.f = start_fct;
-      no_more = (nip = startp) == (service_user *) -1;
-    }
+  no_more = __nss_ethers_lookup2 (&nip, "gethostton_r", NULL, &fct.ptr);
 
   while (no_more == 0)
     {
diff --git a/inet/ether_ntoh.c b/inet/ether_ntoh.c
index e409773601..5ef654292c 100644
--- a/inet/ether_ntoh.c
+++ b/inet/ether_ntoh.c
@@ -31,9 +31,7 @@  typedef int (*lookup_function) (const struct ether_addr *, struct etherent *,
 int
 ether_ntohost (char *hostname, const struct ether_addr *addr)
 {
-  static service_user *startp;
-  static lookup_function start_fct;
-  service_user *nip;
+  nss_action_list nip;
   union
   {
     lookup_function f;
@@ -43,22 +41,7 @@  ether_ntohost (char *hostname, const struct ether_addr *addr)
   enum nss_status status = NSS_STATUS_UNAVAIL;
   struct etherent etherent;
 
-  if (startp == NULL)
-    {
-      no_more = __nss_ethers_lookup2 (&nip, "getntohost_r", NULL, &fct.ptr);
-      if (no_more)
-	startp = (service_user *) -1;
-      else
-	{
-	  startp = nip;
-	  start_fct = fct.f;
-	}
-    }
-  else
-    {
-      fct.f = start_fct;
-      no_more = (nip = startp) == (service_user *) -1;
-    }
+  no_more = __nss_ethers_lookup2 (&nip, "getntohost_r", NULL, &fct.ptr);
 
   while (no_more == 0)
     {
diff --git a/inet/getnetgrent_r.c b/inet/getnetgrent_r.c
index 78a66eee00..9c75af6f77 100644
--- a/inet/getnetgrent_r.c
+++ b/inet/getnetgrent_r.c
@@ -39,40 +39,12 @@  static struct __netgrent dataset;
 /* Set up NIP to run through the services.  Return nonzero if there are no
    services (left).  */
 static int
-setup (void **fctp, service_user **nipp)
+setup (void **fctp, nss_action_list *nipp)
 {
-  /* Remember the first service_entry, it's always the same.  */
-  static bool startp_initialized;
-  static service_user *startp;
   int no_more;
 
-  if (!startp_initialized)
-    {
-      /* Executing this more than once at the same time must yield the
-	 same result every time.  So we need no locking.  */
-      no_more = __nss_netgroup_lookup2 (nipp, "setnetgrent", NULL, fctp);
-      startp = no_more ? (service_user *) -1 : *nipp;
-#ifdef PTR_MANGLE
-      PTR_MANGLE (startp);
-#endif
-      atomic_write_barrier ();
-      startp_initialized = true;
-    }
-  else
-    {
-      service_user *nip = startp;
-#ifdef PTR_DEMANGLE
-      PTR_DEMANGLE (nip);
-#endif
-      if (nip == (service_user *) -1)
-	/* No services at all.  */
-	return 1;
-
-      /* Reset to the beginning of the service list.  */
-      *nipp = nip;
-      /* Look up the first function.  */
-      no_more = __nss_lookup (nipp, "setnetgrent", NULL, fctp);
-    }
+  no_more = __nss_netgroup_lookup2 (nipp, "setnetgrent", NULL, fctp);
+
   return no_more;
 }
 
@@ -100,7 +72,7 @@  endnetgrent_hook (struct __netgrent *datap)
 {
   enum nss_status (*endfct) (struct __netgrent *);
 
-  if (datap->nip == NULL || datap->nip == (service_user *) -1l)
+  if (datap->nip == NULL || datap->nip == (nss_action_list) -1l)
     return;
 
   endfct = __nss_lookup_function (datap->nip, "endnetgrent");
@@ -133,7 +105,7 @@  __internal_setnetgrent_reuse (const char *group, struct __netgrent *datap,
       /* Ignore status, we force check in `__nss_next2'.  */
       status = DL_CALL_FCT (*fct.f, (group, datap));
 
-      service_user *old_nip = datap->nip;
+      nss_action_list old_nip = datap->nip;
       no_more = __nss_next2 (&datap->nip, "setnetgrent", NULL, &fct.ptr,
 			     status, 0);
 
@@ -275,7 +247,7 @@  __internal_getnetgrent_r (char **hostp, char **userp, char **domainp,
       /* This bogus function pointer is a special marker left by
 	 __nscd_setnetgrent to tell us to use the data it left
 	 before considering any modules.  */
-      if (datap->nip == (service_user *) -1l)
+      if (datap->nip == (nss_action_list) -1l)
 	fct = nscd_getnetgrent;
       else
 #endif
diff --git a/inet/netgroup.h b/inet/netgroup.h
index 53081db78f..910094b9ca 100644
--- a/inet/netgroup.h
+++ b/inet/netgroup.h
@@ -64,7 +64,7 @@  struct __netgrent
 
   /* This handle for the NSS data base is shared between all
      set/get/endXXXent functions.  */
-  service_user *nip;
+  struct nss_action *nip;
 };
 
 
diff --git a/malloc/set-freeres.c b/malloc/set-freeres.c
index b328cca7c6..0769ad7a6f 100644
--- a/malloc/set-freeres.c
+++ b/malloc/set-freeres.c
@@ -20,7 +20,7 @@ 
 #include <set-hooks.h>
 #include <libc-internal.h>
 
-#include "../nss/nss_module.h"
+#include "../nss/nsswitch.h"
 #include "../libio/libioP.h"
 
 DEFINE_HOOK (__libc_subfreeres, (void));
@@ -43,6 +43,8 @@  __libc_freeres (void)
       void *const *p;
 
       call_function_static_weak (__nss_module_freeres);
+      call_function_static_weak (__nss_action_freeres);
+      call_function_static_weak (__nss_database_freeres);
 
       _IO_cleanup ();
 
diff --git a/nscd/aicache.c b/nscd/aicache.c
index ee9c9b8843..ce3bb382ce 100644
--- a/nscd/aicache.c
+++ b/nscd/aicache.c
@@ -71,20 +71,15 @@  addhstaiX (struct database_dyn *db, int fd, request_header *req,
 	dbg_log (_("Reloading \"%s\" in hosts cache!"), (char *) key);
     }
 
-  static service_user *hosts_database;
-  service_user *nip;
+  nss_action_list nip;
   int no_more;
   int rc6 = 0;
   int rc4 = 0;
   int herrno = 0;
 
-  if (hosts_database == NULL)
-    no_more = __nss_database_lookup2 ("hosts", NULL,
-				      "dns [!UNAVAIL=return] files",
-				      &hosts_database);
-  else
-    no_more = 0;
-  nip = hosts_database;
+  no_more = __nss_database_lookup2 ("hosts", NULL,
+				    "dns [!UNAVAIL=return] files",
+				    &nip);
 
   /* Initialize configurations.  */
   struct resolv_context *ctx = __resolv_context_get ();
@@ -442,10 +437,10 @@  next_nip:
       if (nss_next_action (nip, status[1]) == NSS_ACTION_RETURN)
 	break;
 
-      if (nip->next == NULL)
+      if (nip[1].module == NULL)
 	no_more = -1;
       else
-	nip = nip->next;
+	++ nip;
     }
 
   /* No result found.  Create a negative result record.  */
diff --git a/nscd/gai.c b/nscd/gai.c
index 2e19530102..aaaddd8fe5 100644
--- a/nscd/gai.c
+++ b/nscd/gai.c
@@ -43,4 +43,4 @@ 
 #include <check_native.c>
 
 /* Some variables normally defined in libc.  */
-service_user *__nss_hosts_database attribute_hidden;
+nss_action_list __nss_hosts_database attribute_hidden;
diff --git a/nscd/initgrcache.c b/nscd/initgrcache.c
index a1102e4e46..7f110d51b4 100644
--- a/nscd/initgrcache.c
+++ b/nscd/initgrcache.c
@@ -77,8 +77,8 @@  addinitgroupsX (struct database_dyn *db, int fd, request_header *req,
 	dbg_log (_("Reloading \"%s\" in group cache!"), (char *) key);
     }
 
-  static service_user *group_database;
-  service_user *nip;
+  static nss_action_list group_database;
+  nss_action_list nip;
   int no_more;
 
   if (group_database == NULL)
@@ -161,10 +161,10 @@  addinitgroupsX (struct database_dyn *db, int fd, request_header *req,
 	  && nss_next_action (nip, status) == NSS_ACTION_RETURN)
 	 break;
 
-      if (nip->next == NULL)
+      if (nip[1].module == NULL)
 	no_more = -1;
       else
-	nip = nip->next;
+	++ nip;
     }
 
   bool all_written;
diff --git a/nscd/netgroupcache.c b/nscd/netgroupcache.c
index 88c69d1e9c..67be24e837 100644
--- a/nscd/netgroupcache.c
+++ b/nscd/netgroupcache.c
@@ -124,7 +124,7 @@  addgetnetgrentX (struct database_dyn *db, int fd, request_header *req,
 	dbg_log (_("Reloading \"%s\" in netgroup cache!"), key);
     }
 
-  static service_user *netgroup_database;
+  static nss_action_list netgroup_database;
   time_t timeout;
   struct dataset *dataset;
   bool cacheable = false;
@@ -175,7 +175,7 @@  addgetnetgrentX (struct database_dyn *db, int fd, request_header *req,
 	void *ptr;
       } setfct;
 
-      service_user *nip = netgroup_database;
+      nss_action_list nip = netgroup_database;
       int no_more = __nss_lookup (&nip, "setnetgrent", NULL, &setfct.ptr);
       while (!no_more)
 	{
diff --git a/nscd/nscd_netgroup.c b/nscd/nscd_netgroup.c
index 7b8dc4081a..0ed9c0cda6 100644
--- a/nscd/nscd_netgroup.c
+++ b/nscd/nscd_netgroup.c
@@ -116,7 +116,7 @@  __nscd_setnetgrent (const char *group, struct __netgrent *datap)
       datap->data_size = datalen;
       datap->cursor = respdata;
       datap->first = 1;
-      datap->nip = (service_user *) -1l;
+      datap->nip = (nss_action_list) -1l;
       datap->known_groups = NULL;
       datap->needed_groups = NULL;
 
diff --git a/nss/Makefile b/nss/Makefile
index ccd1a6ae4f..83323cb934 100644
--- a/nss/Makefile
+++ b/nss/Makefile
@@ -66,7 +66,8 @@  tests-container = \
 			  tst-nss-test3 \
 			  tst-nss-files-hosts-long \
 			  tst-nss-db-endpwent \
-			  tst-nss-db-endgrent
+			  tst-nss-db-endgrent \
+			  tst-reload1
 
 # Tests which need libdl
 ifeq (yes,$(build-shared))
diff --git a/nss/XXX-lookup.c b/nss/XXX-lookup.c
index e26c6d7f8b..8ebd9a740a 100644
--- a/nss/XXX-lookup.c
+++ b/nss/XXX-lookup.c
@@ -53,12 +53,11 @@ 
 #endif
 
 int
-DB_LOOKUP_FCT (service_user **ni, const char *fct_name, const char *fct2_name,
+DB_LOOKUP_FCT (nss_action_list *ni, const char *fct_name, const char *fct2_name,
 	       void **fctp)
 {
-  if (DATABASE_NAME_SYMBOL == NULL
-      && __nss_database_lookup2 (DATABASE_NAME_STRING, ALTERNATE_NAME_STRING,
-				 DEFAULT_CONFIG, &DATABASE_NAME_SYMBOL) < 0)
+  if (__nss_database_lookup2 (DATABASE_NAME_STRING, ALTERNATE_NAME_STRING,
+			      DEFAULT_CONFIG, &DATABASE_NAME_SYMBOL) < 0)
     return -1;
 
   *ni = DATABASE_NAME_SYMBOL;
diff --git a/nss/compat-lookup.c b/nss/compat-lookup.c
index 9af34150bd..07fcc94f58 100644
--- a/nss/compat-lookup.c
+++ b/nss/compat-lookup.c
@@ -29,7 +29,7 @@ 
    glibc 2.7 and earlier and glibc 2.8 and later, even on i386.  */
 int
 attribute_compat_text_section
-__nss_passwd_lookup (service_user **ni, const char *fct_name, void **fctp)
+__nss_passwd_lookup (nss_action_list *ni, const char *fct_name, void **fctp)
 {
   __set_errno (ENOSYS);
   return -1;
@@ -46,11 +46,11 @@  compat_symbol (libc, __nss_hosts_lookup, __nss_hosts_lookup, GLIBC_2_0);
 
 /* These functions were exported under a non-GLIBC_PRIVATE version,
    even though it is not usable externally due to the service_user
-   type dependency.  */
+   (now nss_action_list) type dependency.  */
 
 int
 attribute_compat_text_section
-__nss_next (service_user **ni, const char *fct_name, void **fctp, int status,
+__nss_next (nss_action_list *ni, const char *fct_name, void **fctp, int status,
             int all_values)
 {
   return -1;
@@ -60,7 +60,7 @@  compat_symbol (libc, __nss_next, __nss_next, GLIBC_2_0);
 int
 attribute_compat_text_section
 __nss_database_lookup (const char *database, const char *alternate_name,
-                       const char *defconfig, service_user **ni)
+                       const char *defconfig, nss_action_list *ni)
 {
   *ni = NULL;
   return -1;
diff --git a/nss/getXXbyYY_r.c b/nss/getXXbyYY_r.c
index e8c9ab1bb3..6c287a6127 100644
--- a/nss/getXXbyYY_r.c
+++ b/nss/getXXbyYY_r.c
@@ -179,7 +179,7 @@  typedef enum nss_status (*lookup_function) (ADD_PARAMS, LOOKUP_TYPE *, char *,
 					    EXTRA_PARAMS);
 
 /* The lookup function for the first entry of this service.  */
-extern int DB_LOOKUP_FCT (service_user **nip, const char *name,
+extern int DB_LOOKUP_FCT (nss_action_list *nip, const char *name,
 			  const char *name2, void **fctp);
 libc_hidden_proto (DB_LOOKUP_FCT)
 
@@ -189,10 +189,7 @@  INTERNAL (REENTRANT_NAME) (ADD_PARAMS, LOOKUP_TYPE *resbuf, char *buffer,
 			   size_t buflen, LOOKUP_TYPE **result H_ERRNO_PARM
 			   EXTRA_PARAMS)
 {
-  static bool startp_initialized;
-  static service_user *startp;
-  static lookup_function start_fct;
-  service_user *nip;
+  nss_action_list nip;
   int do_merge = 0;
   LOOKUP_TYPE mergegrp;
   char *mergebuf = NULL;
@@ -227,6 +224,7 @@  INTERNAL (REENTRANT_NAME) (ADD_PARAMS, LOOKUP_TYPE *resbuf, char *buffer,
   PREPROCESS;
 #endif
 
+
 #ifdef HANDLE_DIGITS_DOTS
   switch (__nss_hostname_digits_dots (name, resbuf, &buffer, NULL,
 				      buflen, result, &status, AF_VAL,
@@ -264,47 +262,8 @@  INTERNAL (REENTRANT_NAME) (ADD_PARAMS, LOOKUP_TYPE *resbuf, char *buffer,
     }
 #endif
 
-  if (! startp_initialized)
-    {
-      no_more = DB_LOOKUP_FCT (&nip, REENTRANT_NAME_STRING,
-			       REENTRANT2_NAME_STRING, &fct.ptr);
-      if (no_more)
-	{
-	  void *tmp_ptr = (service_user *) -1l;
-#ifdef PTR_MANGLE
-	  PTR_MANGLE (tmp_ptr);
-#endif
-	  startp = tmp_ptr;
-	}
-      else
-	{
-	  void *tmp_ptr = fct.l;
-#ifdef PTR_MANGLE
-	  PTR_MANGLE (tmp_ptr);
-#endif
-	  start_fct = tmp_ptr;
-	  tmp_ptr = nip;
-#ifdef PTR_MANGLE
-	  PTR_MANGLE (tmp_ptr);
-#endif
-	  startp = tmp_ptr;
-	}
-
-      /* Make sure start_fct and startp are written before
-	 startp_initialized.  */
-      atomic_write_barrier ();
-      startp_initialized = true;
-    }
-  else
-    {
-      fct.l = start_fct;
-      nip = startp;
-#ifdef PTR_DEMANGLE
-      PTR_DEMANGLE (fct.l);
-      PTR_DEMANGLE (nip);
-#endif
-      no_more = nip == (service_user *) -1l;
-    }
+  no_more = DB_LOOKUP_FCT (&nip, REENTRANT_NAME_STRING,
+			   REENTRANT2_NAME_STRING, &fct.ptr);
 
   while (no_more == 0)
     {
diff --git a/nss/getXXent_r.c b/nss/getXXent_r.c
index 8b64fcd795..dfcbd01f66 100644
--- a/nss/getXXent_r.c
+++ b/nss/getXXent_r.c
@@ -95,11 +95,11 @@ 
 
 /* This handle for the NSS data base is shared between all
    set/get/endXXXent functions.  */
-static service_user *nip;
+static nss_action_list nip;
 /* Remember the last service used since the last call to  `endXXent'.  */
-static service_user *last_nip;
-/* Remember the first service_entry, it's always the same.  */
-static service_user *startp;
+static nss_action_list last_nip;
+/* Remember the first service_entry across set/get/endent.  */
+static nss_action_list startp;
 
 #ifdef STAYOPEN_TMP
 /* We need to remember the last `stayopen' flag given by the user
@@ -112,7 +112,7 @@  static STAYOPEN_TMP;
 __libc_lock_define_initialized (static, lock)
 
 /* The lookup function for the first entry of this service.  */
-extern int DB_LOOKUP_FCT (service_user **nip, const char *name,
+extern int DB_LOOKUP_FCT (nss_action_list *nip, const char *name,
 			  const char *name2, void **fctp);
 libc_hidden_proto (DB_LOOKUP_FCT)
 
diff --git a/nss/getnssent_r.c b/nss/getnssent_r.c
index 8a366bc7ea..84e977c33b 100644
--- a/nss/getnssent_r.c
+++ b/nss/getnssent_r.c
@@ -25,20 +25,20 @@ 
    services (left).  */
 static int
 setup (const char *func_name, db_lookup_function lookup_fct,
-       void **fctp, service_user **nip, service_user **startp, int all)
+       void **fctp, nss_action_list *nip, nss_action_list *startp, int all)
 {
   int no_more;
-  if (*startp == NULL)
+  if (*startp == NULL || all)
     {
       no_more = lookup_fct (nip, func_name, NULL, fctp);
-      *startp = no_more ? (service_user *) -1l : *nip;
+      *startp = no_more ? (nss_action_list) -1l : *nip;
     }
-  else if (*startp == (service_user *) -1l)
+  else if (*startp == (nss_action_list) -1l)
     /* No services at all.  */
     return 1;
   else
     {
-      if (all || !*nip)
+      if (!*nip)
 	/* Reset to the beginning of the service list.  */
 	*nip = *startp;
       /* Look up the first function.  */
@@ -49,8 +49,8 @@  setup (const char *func_name, db_lookup_function lookup_fct,
 
 void
 __nss_setent (const char *func_name, db_lookup_function lookup_fct,
-	      service_user **nip, service_user **startp,
-	      service_user **last_nip, int stayopen, int *stayopen_tmp,
+	      nss_action_list *nip, nss_action_list *startp,
+	      nss_action_list *last_nip, int stayopen, int *stayopen_tmp,
 	      int res)
 {
   union
@@ -110,8 +110,8 @@  __nss_setent (const char *func_name, db_lookup_function lookup_fct,
 
 void
 __nss_endent (const char *func_name, db_lookup_function lookup_fct,
-	      service_user **nip, service_user **startp,
-	      service_user **last_nip, int res)
+	      nss_action_list *nip, nss_action_list *startp,
+	      nss_action_list *last_nip, int res)
 {
   union
   {
@@ -154,8 +154,8 @@  int
 __nss_getent_r (const char *getent_func_name,
 		const char *setent_func_name,
 		db_lookup_function lookup_fct,
-		service_user **nip, service_user **startp,
-		service_user **last_nip, int *stayopen_tmp, int res,
+		nss_action_list *nip, nss_action_list *startp,
+		nss_action_list *last_nip, int *stayopen_tmp, int res,
 		void *resbuf, char *buffer, size_t buflen,
 		void **result, int *h_errnop)
 {
diff --git a/nss/nss_action.c b/nss/nss_action.c
index b9c3b93fea..5008323859 100644
--- a/nss/nss_action.c
+++ b/nss/nss_action.c
@@ -16,7 +16,7 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#include <nss_action.h>
+#include <nsswitch.h>
 
 #include <string.h>
 #include <libc-lock.h>
diff --git a/nss/nss_action_parse.c b/nss/nss_action_parse.c
index ada3acbb08..7a80582842 100644
--- a/nss/nss_action_parse.c
+++ b/nss/nss_action_parse.c
@@ -16,8 +16,7 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#include "nss_action.h"
-#include "nss_module.h"
+#include <nsswitch.h>
 
 #include <ctype.h>
 #include <string.h>
@@ -169,18 +168,13 @@  nss_action_list
   action_list_init (&list);
   if (nss_action_parse (line, &list))
     {
-      size_t size = action_list_size (&list);
-      nss_action_list result
-        = malloc (sizeof (*result) * (size + 1));
-      if (result == NULL)
-        {
-          action_list_free (&list);
-          return NULL;
-        }
-      memcpy (result, action_list_begin (&list), sizeof (*result) * size);
-      /* Sentinel.  */
-      result[size].module = NULL;
-      return result;
+      size_t size;
+      struct nss_action null_service
+        = { .module = NULL, };
+
+      action_list_add (&list, null_service);
+      size = action_list_size (&list);
+      return __nss_action_allocate (action_list_begin (&list), size);
     }
   else if (action_list_has_failed (&list))
     {
diff --git a/nss/nss_compat/compat-grp.c b/nss/nss_compat/compat-grp.c
index 510d49e8c7..6637c96355 100644
--- a/nss/nss_compat/compat-grp.c
+++ b/nss/nss_compat/compat-grp.c
@@ -30,7 +30,7 @@ 
 
 NSS_DECLARE_MODULE_FUNCTIONS (compat)
 
-static service_user *ni;
+static nss_action_list ni;
 static enum nss_status (*setgrent_impl) (int stayopen);
 static enum nss_status (*getgrnam_r_impl) (const char *name,
 					   struct group * grp, char *buffer,
diff --git a/nss/nss_compat/compat-initgroups.c b/nss/nss_compat/compat-initgroups.c
index c0dcdf839d..99f7df613a 100644
--- a/nss/nss_compat/compat-initgroups.c
+++ b/nss/nss_compat/compat-initgroups.c
@@ -33,7 +33,7 @@ 
 
 NSS_DECLARE_MODULE_FUNCTIONS (compat)
 
-static service_user *ni;
+static nss_action_list ni;
 static enum nss_status (*initgroups_dyn_impl) (const char *, gid_t,
 					       long int *, long int *,
 					       gid_t **, long int, int *);
diff --git a/nss/nss_compat/compat-pwd.c b/nss/nss_compat/compat-pwd.c
index 3a212a0dab..789878ccbd 100644
--- a/nss/nss_compat/compat-pwd.c
+++ b/nss/nss_compat/compat-pwd.c
@@ -34,7 +34,7 @@ 
 
 NSS_DECLARE_MODULE_FUNCTIONS (compat)
 
-static service_user *ni;
+static nss_action_list ni;
 static enum nss_status (*setpwent_impl) (int stayopen);
 static enum nss_status (*getpwnam_r_impl) (const char *name,
 					   struct passwd * pwd, char *buffer,
diff --git a/nss/nss_compat/compat-spwd.c b/nss/nss_compat/compat-spwd.c
index d802ee0302..7310da85bd 100644
--- a/nss/nss_compat/compat-spwd.c
+++ b/nss/nss_compat/compat-spwd.c
@@ -34,7 +34,7 @@ 
 
 NSS_DECLARE_MODULE_FUNCTIONS (compat)
 
-static service_user *ni;
+static nss_action_list ni;
 static enum nss_status (*setspent_impl) (int stayopen);
 static enum nss_status (*getspnam_r_impl) (const char *name, struct spwd * sp,
 					   char *buffer, size_t buflen,
diff --git a/nss/nss_database.c b/nss/nss_database.c
index 40162e0bc2..8508af51e3 100644
--- a/nss/nss_database.c
+++ b/nss/nss_database.c
@@ -226,6 +226,39 @@  process_line (struct nss_database_data *data, char *line)
   return true;
 }
 
+int
+__nss_configure_lookup (const char *dbname, const char *service_line)
+{
+  int db;
+  nss_action_list result;
+  struct nss_database_state *local;
+
+  /* Convert named database to index.  */
+  db = name_to_database_index (dbname);
+  if (db < 0)
+    /* Not our database (e.g., sudoers).  */
+    return -1;
+
+  /* Force any load/cache/read whatever to happen, so we can override
+     it.  */
+  __nss_database_get (db, &result);
+
+  local = nss_database_state_get ();
+
+  result = __nss_action_parse (service_line);
+  if (result == NULL)
+    return -1;
+
+  atomic_store_release (&local->data.reload_disabled, 1);
+  local->data.services[db] = result;
+
+#ifdef USE_NSCD
+  __nss_database_custom[db] = true;
+#endif
+
+  return 0;
+}
+
 /* Iterate over the lines in FP, parse them, and store them in DATA.
    Return false on memory allocation failure, true on success.  */
 static bool
@@ -326,8 +359,11 @@  nss_database_check_reload_and_get (struct nss_database_state *local,
      may have loaded the configuration first, so synchronize with the
      Release MO store there.  */
   if (atomic_load_acquire (&local->data.reload_disabled))
-    /* No reload, so there is no error.  */
-    return true;
+    {
+      *result = local->data.services[database_index];
+      /* No reload, so there is no error.  */
+      return true;
+    }
 
   struct file_change_detection initial;
   if (!__file_change_detection_for_path (&initial, _PATH_NSSWITCH_CONF))
diff --git a/nss/nss_module.c b/nss/nss_module.c
index 1c9eec0c01..59e46c5acb 100644
--- a/nss/nss_module.c
+++ b/nss/nss_module.c
@@ -16,7 +16,9 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#include <nss_module.h>
+#include <nsswitch.h>
+#include <nscd/nscd.h>
+#include <nscd/nscd_proto.h>
 
 #include <array_length.h>
 #include <assert.h>
@@ -357,6 +359,66 @@  __nss_module_get_function (struct nss_module *module, const char *name)
   return fptr;
 }
 
+#if defined SHARED && defined USE_NSCD
+/* Load all libraries for the service.  */
+static void
+nss_load_all_libraries (const char *service, const char *def)
+{
+  nss_action_list ni = NULL;
+
+  if (__nss_database_lookup2 (service, NULL, def, &ni) == 0)
+    while (ni->module != NULL)
+      {
+        __nss_module_load (ni->module);
+        ++ ni;
+      }
+}
+
+define_traced_file (pwd, _PATH_NSSWITCH_CONF);
+define_traced_file (grp, _PATH_NSSWITCH_CONF);
+define_traced_file (hst, _PATH_NSSWITCH_CONF);
+define_traced_file (serv, _PATH_NSSWITCH_CONF);
+define_traced_file (netgr, _PATH_NSSWITCH_CONF);
+
+/* Called by nscd and nscd alone.  */
+void
+__nss_disable_nscd (void (*cb) (size_t, struct traced_file *))
+{
+  void (*cb1) (size_t, struct traced_file *);
+  cb1 = cb;
+# ifdef PTR_MANGLE
+  PTR_MANGLE (cb);
+# endif
+  nscd_init_cb = cb;
+  is_nscd = true;
+
+  /* Find all the relevant modules so that the init functions are called.  */
+  nss_load_all_libraries ("passwd", DEFAULT_CONFIG);
+  nss_load_all_libraries ("group", DEFAULT_CONFIG);
+  nss_load_all_libraries ("hosts", "dns [!UNAVAIL=return] files");
+  nss_load_all_libraries ("services", NULL);
+
+  /* Make sure NSCD purges its cache if nsswitch.conf changes.  */
+  init_traced_file (&pwd_traced_file.file, _PATH_NSSWITCH_CONF, 0);
+  cb1 (pwddb, &pwd_traced_file.file);
+  init_traced_file (&grp_traced_file.file, _PATH_NSSWITCH_CONF, 0);
+  cb1 (grpdb, &grp_traced_file.file);
+  init_traced_file (&hst_traced_file.file, _PATH_NSSWITCH_CONF, 0);
+  cb1 (hstdb, &hst_traced_file.file);
+  init_traced_file (&serv_traced_file.file, _PATH_NSSWITCH_CONF, 0);
+  cb1 (servdb, &serv_traced_file.file);
+  init_traced_file (&netgr_traced_file.file, _PATH_NSSWITCH_CONF, 0);
+  cb1 (netgrdb, &netgr_traced_file.file);
+
+  /* Disable all uses of NSCD.  */
+  __nss_not_use_nscd_passwd = -1;
+  __nss_not_use_nscd_group = -1;
+  __nss_not_use_nscd_hosts = -1;
+  __nss_not_use_nscd_services = -1;
+  __nss_not_use_nscd_netgroup = -1;
+}
+#endif
+
 void __libc_freeres_fn_section
 __nss_module_freeres (void)
 {
diff --git a/nss/nss_test.h b/nss/nss_test.h
index 49a9aff2fd..b6c6ad2333 100644
--- a/nss/nss_test.h
+++ b/nss/nss_test.h
@@ -33,10 +33,12 @@ 
 
 #include <pwd.h>
 #include <grp.h>
+#include <netdb.h>
 
 typedef struct test_tables {
   struct passwd *pwd_table;
   struct group *grp_table;
+  struct hostent *host_table;
 } test_tables;
 
 extern void _nss_test1_init_hook (test_tables *) __attribute__((weak));
@@ -44,9 +46,11 @@  extern void _nss_test2_init_hook (test_tables *) __attribute__((weak));
 
 #define PWD_LAST()    { .pw_name = NULL, .pw_uid = 0 }
 #define GRP_LAST()    { .gr_name = NULL, .gr_gid = 0 }
+#define HOST_LAST()    { .h_name = NULL, .h_aliases = NULL, .h_length = 0, .h_addr_list = NULL }
 
 #define PWD_ISLAST(p)    ((p)->pw_name == NULL && (p)->pw_uid == 0)
 #define GRP_ISLAST(g)    ((g)->gr_name == NULL && (g)->gr_gid == 0)
+#define HOST_ISLAST(h)    ((h)->h_name == NULL && (h)->h_length == 0)
 
 /* Macros to fill in the tables easily.  */
 
@@ -72,6 +76,11 @@  extern void _nss_test2_init_hook (test_tables *) __attribute__((weak));
     { .gr_name = (char *) n, .gr_passwd = (char *) "*", .gr_gid = u, \
       .gr_mem = (char **) m }
 
+#define HOST(u)								\
+    { .h_name = (char *) "name" #u, .h_aliases = NULL, .h_addrtype = u,	\
+      .h_length = 4,							\
+      .h_addr_list = (char **) hostaddr_##u  }
+
 /*------------------------------------------------------------*/
 
 /* Helper functions for testing passwd entries.  Call
diff --git a/nss/nss_test1.c b/nss/nss_test1.c
index 13532cd7ab..212719dc98 100644
--- a/nss/nss_test1.c
+++ b/nss/nss_test1.c
@@ -66,6 +66,9 @@  static int npwd_data = default_npwd_data;
 static struct group *grp_data = NULL;
 static int ngrp_data = 0;
 
+static struct hostent *host_data = NULL;
+static int nhost_data = 0;
+
 /* This function will get called, and once per session, look back into
    the test case's executable for an init hook function, and call
    it.  */
@@ -99,6 +102,13 @@  init(void)
 	    ;
 	  ngrp_data = i;
 	}
+      if (t.host_table)
+	{
+	  host_data = t.host_table;
+	  for (i=0; ! HOST_ISLAST(& host_data[i]); i++)
+	    ;
+	  nhost_data = i;
+	}
     }
   initted = 1;
 }
@@ -280,7 +290,7 @@  NAME(getgrent_r) (struct group *result, char *buffer, size_t buflen,
       ++grp_iter;
     }
 
-  pthread_mutex_unlock (&pwd_lock);
+  pthread_mutex_unlock (&grp_lock);
 
   return res;
 }
@@ -312,3 +322,157 @@  NAME(getgrnam_r) (const char *name, struct group *result, char *buffer,
 
   return NSS_STATUS_NOTFOUND;
 }
+
+/* -------------------------------------------------- */
+/* Host handling.  */
+
+static size_t host_iter;
+#define CURHOST host_data[host_iter]
+
+static pthread_mutex_t host_lock = PTHREAD_MUTEX_INITIALIZER;
+
+enum nss_status
+NAME(sethostent) (int stayopen)
+{
+  init();
+  host_iter = 0;
+  return NSS_STATUS_SUCCESS;
+}
+
+
+enum nss_status
+NAME(endhostent) (void)
+{
+  init();
+  return NSS_STATUS_SUCCESS;
+}
+
+static enum nss_status
+copy_host (struct hostent *result, struct hostent *local,
+	    char *buffer, size_t buflen, int *errnop)
+{
+  struct alloc_buffer buf = alloc_buffer_create (buffer, buflen);
+  char **memlist;
+  int i, j;
+
+  if (local->h_addr_list)
+    {
+      i = 0;
+      while (local->h_addr_list[i])
+	++i;
+
+      memlist = alloc_buffer_alloc_array (&buf, char *, i + 1);
+
+      if (memlist) {
+	for (j = 0; j < i; ++j)
+	  memlist[j] = alloc_buffer_maybe_copy_string (&buf, local->h_addr_list[j]);
+	memlist[j] = NULL;
+      }
+
+      result->h_addr_list = memlist;
+    }
+  else
+    {
+      result->h_addr_list = NULL;
+    }
+
+  result->h_aliases = NULL;
+  result->h_addrtype = AF_INET;
+  result->h_length = 4;
+  result->h_name = alloc_buffer_maybe_copy_string (&buf, local->h_name);
+
+  if (alloc_buffer_has_failed (&buf))
+    {
+      *errnop = ERANGE;
+      return NSS_STATUS_TRYAGAIN;
+    }
+
+  return NSS_STATUS_SUCCESS;
+}
+
+
+enum nss_status
+NAME(gethostent_r) (struct hostent *ret, char *buffer, size_t buflen,
+		    struct hostent **result, int *errnop)
+{
+  int res = NSS_STATUS_SUCCESS;
+
+  init();
+  pthread_mutex_lock (&host_lock);
+
+  if (host_iter >= nhost_data)
+    {
+      res = NSS_STATUS_NOTFOUND;
+      *result = NULL;
+    }
+  else
+    {
+      res = copy_host (ret, &CURHOST, buffer, buflen, errnop);
+      *result = ret;
+      ++host_iter;
+    }
+
+  pthread_mutex_unlock (&host_lock);
+
+  return res;
+}
+
+enum nss_status
+NAME(gethostbyname3_r) (const char *name, int af, struct hostent *ret,
+			     char *buffer, size_t buflen, int *errnop,
+			     int *h_errnop, int32_t *ttlp, char **canonp)
+{
+  init();
+
+  for (size_t idx = 0; idx < nhost_data; ++idx)
+    if (strcmp (host_data[idx].h_name, name) == 0)
+      return copy_host (ret, & host_data[idx], buffer, buflen, h_errnop);
+
+  return NSS_STATUS_NOTFOUND;
+}
+
+enum nss_status
+NAME(gethostbyname_r) (const char *name, struct hostent *result,
+		       char *buffer, size_t buflen,
+		       int *errnop, int *h_errnop)
+{
+  return NAME(gethostbyname3_r) (name, AF_INET, result, buffer, buflen,
+				 errnop, h_errnop, NULL, NULL);
+}
+
+enum nss_status
+NAME(gethostbyname2_r) (const char *name, int af, struct hostent *result,
+			char *buffer, size_t buflen,
+			int *errnop, int *h_errnop)
+{
+  return NAME(gethostbyname3_r) (name, af, result, buffer, buflen,
+				 errnop, h_errnop, NULL, NULL);
+}
+
+enum nss_status
+NAME(gethostbyaddr2_r) (const void *addr, socklen_t len, int af,
+			struct hostent *result, char *buffer, size_t buflen,
+			int *errnop, int *h_errnop, int32_t *ttlp)
+{
+  init();
+
+  /* Support this later.  */
+  if (len != 4)
+    return NSS_STATUS_NOTFOUND;
+
+  for (size_t idx = 0; idx < nhost_data; ++idx)
+    if (memcmp (host_data[idx].h_addr, addr, len) == 0)
+      return copy_host (result, & host_data[idx], buffer, buflen, h_errnop);
+	
+  return NSS_STATUS_NOTFOUND;
+}
+
+/* Note: only the first address is supported, intentionally.  */
+enum nss_status
+NAME(gethostbyaddr_r) (const void *addr, socklen_t len, int af,
+		       struct hostent *result, char *buffer, size_t buflen,
+		       int *errnop, int *h_errnop)
+{
+  return NAME(gethostbyaddr2_r) (addr, len, af, result, buffer, buflen,
+				 errnop, h_errnop, NULL);
+}
diff --git a/nss/nsswitch.c b/nss/nsswitch.c
index 8d7b69d4bc..9b73296c5f 100644
--- a/nss/nsswitch.c
+++ b/nss/nsswitch.c
@@ -32,6 +32,7 @@ 
 #include <netinet/ether.h>
 #include <pwd.h>
 #include <shadow.h>
+#include <unistd.h>
 
 #if !defined DO_STATIC_NSS || defined SHARED
 # include <gnu/lib-names.h>
@@ -42,36 +43,20 @@ 
 #include <sysdep.h>
 #include <config.h>
 
-/* Prototypes for the local functions.  */
-static name_database *nss_parse_file (const char *fname);
-static name_database_entry *nss_getline (char *line);
-static service_user *nss_parse_service_list (const char *line);
-#if !defined DO_STATIC_NSS || defined SHARED
-static service_library *nss_new_service (name_database *database,
-					 const char *name);
-#endif
-
-
 /* Declare external database variables.  */
 #define DEFINE_DATABASE(name)						      \
-  service_user *__nss_##name##_database attribute_hidden;		      \
+  nss_action_list __nss_##name##_database attribute_hidden;		      \
   weak_extern (__nss_##name##_database)
 #include "databases.def"
 #undef DEFINE_DATABASE
 
-/* Structure to map database name to variable.  */
-static const struct
-{
-  const char name[10];
-  service_user **dbp;
-} databases[] =
-{
-#define DEFINE_DATABASE(name)						      \
-  { #name, &__nss_##name##_database },
-#include "databases.def"
+
 #undef DEFINE_DATABASE
+#define DEFINE_DATABASE(name)  #name,
+static const char * database_names[] = {
+#include "databases.def"
+  NULL
 };
-#define ndatabases (sizeof (databases) / sizeof (databases[0]))
 
 #ifdef USE_NSCD
 /* Flags whether custom rules for database is set.  */
@@ -79,103 +64,33 @@  bool __nss_database_custom[NSS_DBSIDX_max];
 #endif
 
 
-__libc_lock_define_initialized (static, lock)
-
-#if !defined DO_STATIC_NSS || defined SHARED
-/* String with revision number of the shared object files.  */
-static const char *const __nss_shlib_revision = LIBNSS_FILES_SO + 15;
-#endif
-
-/* The root of the whole data base.  */
-static name_database *service_table;
-
-/* List of default service lists that were generated by glibc because
-   /etc/nsswitch.conf did not provide a value.
-   The list is only maintained so we can free such service lists in
-   __libc_freeres.  */
-static name_database_entry *defconfig_entries;
-
-
-#if defined USE_NSCD && (!defined DO_STATIC_NSS || defined SHARED)
-/* Nonzero if this is the nscd process.  */
-static bool is_nscd;
-/* The callback passed to the init functions when nscd is used.  */
-static void (*nscd_init_cb) (size_t, struct traced_file *);
-#endif
-
+/*__libc_lock_define_initialized (static, lock)*/
 
 /* -1 == database not found
     0 == database entry pointer stored */
 int
 __nss_database_lookup2 (const char *database, const char *alternate_name,
-			const char *defconfig, service_user **ni)
+			const char *defconfig, nss_action_list *ni)
 {
-  /* Prevent multiple threads to change the service table.  */
-  __libc_lock_lock (lock);
+  int database_id;
 
-  /* Reconsider database variable in case some other thread called
-     `__nss_configure_lookup' while we waited for the lock.  */
-  if (*ni != NULL)
-    {
-      __libc_lock_unlock (lock);
-      return 0;
-    }
+  for (database_id = 0; database_names[database_id]; database_id ++)
+    if (strcmp (database_names[database_id], database) == 0)
+	break;
 
-  /* Are we initialized yet?  */
-  if (service_table == NULL)
-    /* Read config file.  */
-    service_table = nss_parse_file (_PATH_NSSWITCH_CONF);
+  if (database_names[database_id] == NULL)
+    return -1;
 
-  /* Test whether configuration data is available.  */
-  if (service_table != NULL)
+  if (__nss_database_get (database_id, ni))
     {
-      /* Return first `service_user' entry for DATABASE.  */
-      name_database_entry *entry;
-
-      /* XXX Could use some faster mechanism here.  But each database is
-	 only requested once and so this might not be critical.  */
-      for (entry = service_table->entry; entry != NULL; entry = entry->next)
-	if (strcmp (database, entry->name) == 0)
-	  *ni = entry->service;
-
-      if (*ni == NULL && alternate_name != NULL)
-	/* We haven't found an entry so far.  Try to find it with the
-	   alternative name.  */
-	for (entry = service_table->entry; entry != NULL; entry = entry->next)
-	  if (strcmp (alternate_name, entry->name) == 0)
-	    *ni = entry->service;
+      /* Success.  */
+      return 0;
     }
-
-  /* No configuration data is available, either because nsswitch.conf
-     doesn't exist or because it doesn't have a line for this database.
-
-     DEFCONFIG specifies the default service list for this database,
-     or null to use the most common default.  */
-  if (*ni == NULL)
+  else
     {
-      *ni = nss_parse_service_list (defconfig ?: "files");
-      if (*ni != NULL)
-	{
-	  /* Record the memory we've just allocated in defconfig_entries list,
-	     so we can free it later.  */
-	  name_database_entry *entry;
-
-	  /* Allocate ENTRY plus size of name (1 here).  */
-	  entry = (name_database_entry *) malloc (sizeof (*entry) + 1);
-
-	  if (entry != NULL)
-	    {
-	      entry->next = defconfig_entries;
-	      entry->service = *ni;
-	      entry->name[0] = '\0';
-	      defconfig_entries = entry;
-	    }
-	}
+      /* Failure.  */
+      return -1;
     }
-
-  __libc_lock_unlock (lock);
-
-  return *ni != NULL ? 0 : -1;
 }
 libc_hidden_def (__nss_database_lookup2)
 
@@ -184,7 +99,7 @@  libc_hidden_def (__nss_database_lookup2)
     0 == function found
     1 == finished */
 int
-__nss_lookup (service_user **ni, const char *fct_name, const char *fct2_name,
+__nss_lookup (nss_action_list *ni, const char *fct_name, const char *fct2_name,
 	      void **fctp)
 {
   *fctp = __nss_lookup_function (*ni, fct_name);
@@ -193,16 +108,16 @@  __nss_lookup (service_user **ni, const char *fct_name, const char *fct2_name,
 
   while (*fctp == NULL
 	 && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE
-	 && (*ni)->next != NULL)
+	 && (*ni)[1].module != NULL)
     {
-      *ni = (*ni)->next;
+      ++ (*ni);
 
       *fctp = __nss_lookup_function (*ni, fct_name);
       if (*fctp == NULL && fct2_name != NULL)
 	*fctp = __nss_lookup_function (*ni, fct2_name);
     }
 
-  return *fctp != NULL ? 0 : (*ni)->next == NULL ? 1 : -1;
+  return *fctp != NULL ? 0 : (*ni)[1].module == NULL ? 1 : -1;
 }
 libc_hidden_def (__nss_lookup)
 
@@ -211,7 +126,7 @@  libc_hidden_def (__nss_lookup)
     0 == adjusted for next function
     1 == finished */
 int
-__nss_next2 (service_user **ni, const char *fct_name, const char *fct2_name,
+__nss_next2 (nss_action_list *ni, const char *fct_name, const char *fct2_name,
 	     void **fctp, int status, int all_values)
 {
   if (all_values)
@@ -233,12 +148,12 @@  __nss_next2 (service_user **ni, const char *fct_name, const char *fct2_name,
 	 return 1;
     }
 
-  if ((*ni)->next == NULL)
+  if ((*ni)[1].module == NULL)
     return -1;
 
   do
     {
-      *ni = (*ni)->next;
+      ++ (*ni);
 
       *fctp = __nss_lookup_function (*ni, fct_name);
       if (*fctp == NULL && fct2_name != NULL)
@@ -246,675 +161,17 @@  __nss_next2 (service_user **ni, const char *fct_name, const char *fct2_name,
     }
   while (*fctp == NULL
 	 && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE
-	 && (*ni)->next != NULL);
+	 && (*ni)[1].module != NULL);
 
   return *fctp != NULL ? 0 : -1;
 }
 libc_hidden_def (__nss_next2)
 
-int
-__nss_configure_lookup (const char *dbname, const char *service_line)
-{
-  service_user *new_db;
-  size_t cnt;
-
-  for (cnt = 0; cnt < ndatabases; ++cnt)
-    {
-      int cmp = strcmp (dbname, databases[cnt].name);
-      if (cmp == 0)
-	break;
-      if (cmp < 0)
-	{
-	  __set_errno (EINVAL);
-	  return -1;
-	}
-    }
-
-  if (cnt == ndatabases)
-    {
-      __set_errno (EINVAL);
-      return -1;
-    }
-
-  /* Test whether it is really used.  */
-  if (databases[cnt].dbp == NULL)
-    /* Nothing to do, but we could do.  */
-    return 0;
-
-  /* Try to generate new data.  */
-  new_db = nss_parse_service_list (service_line);
-  if (new_db == NULL)
-    {
-      /* Illegal service specification.  */
-      __set_errno (EINVAL);
-      return -1;
-    }
-
-  /* Prevent multiple threads to change the service table.  */
-  __libc_lock_lock (lock);
-
-  /* Install new rules.  */
-  *databases[cnt].dbp = new_db;
-#ifdef USE_NSCD
-  __nss_database_custom[cnt] = true;
-#endif
-
-  __libc_lock_unlock (lock);
-
-  return 0;
-}
-
-
-/* Comparison function for searching NI->known tree.  */
-static int
-known_compare (const void *p1, const void *p2)
-{
-  return p1 == p2 ? 0 : strcmp (*(const char *const *) p1,
-				*(const char *const *) p2);
-}
-
-
-#if !defined DO_STATIC_NSS || defined SHARED
-/* Load library.  */
-static int
-nss_load_library (service_user *ni)
-{
-  if (ni->library == NULL)
-    {
-      /* This service has not yet been used.  Fetch the service
-	 library for it, creating a new one if need be.  If there
-	 is no service table from the file, this static variable
-	 holds the head of the service_library list made from the
-	 default configuration.  */
-      static name_database default_table;
-      ni->library = nss_new_service (service_table ?: &default_table,
-				     ni->name);
-      if (ni->library == NULL)
-	return -1;
-    }
-
-  if (ni->library->lib_handle == NULL)
-    {
-      /* Load the shared library.  */
-      size_t shlen = (7 + strlen (ni->name) + 3
-		      + strlen (__nss_shlib_revision) + 1);
-      int saved_errno = errno;
-      char shlib_name[shlen];
-
-      /* Construct shared object name.  */
-      __stpcpy (__stpcpy (__stpcpy (__stpcpy (shlib_name,
-					      "libnss_"),
-				    ni->name),
-			  ".so"),
-		__nss_shlib_revision);
-
-      ni->library->lib_handle = __libc_dlopen (shlib_name);
-      if (ni->library->lib_handle == NULL)
-	{
-	  /* Failed to load the library.  */
-	  ni->library->lib_handle = (void *) -1l;
-	  __set_errno (saved_errno);
-	}
-# ifdef USE_NSCD
-      else if (is_nscd)
-	{
-	  /* Call the init function when nscd is used.  */
-	  size_t initlen = (5 + strlen (ni->name)
-			    + strlen ("_init") + 1);
-	  char init_name[initlen];
-
-	  /* Construct the init function name.  */
-	  __stpcpy (__stpcpy (__stpcpy (init_name,
-					"_nss_"),
-			      ni->name),
-		    "_init");
-
-	  /* Find the optional init function.  */
-	  void (*ifct) (void (*) (size_t, struct traced_file *))
-	    = __libc_dlsym (ni->library->lib_handle, init_name);
-	  if (ifct != NULL)
-	    {
-	      void (*cb) (size_t, struct traced_file *) = nscd_init_cb;
-#  ifdef PTR_DEMANGLE
-	      PTR_DEMANGLE (cb);
-#  endif
-	      ifct (cb);
-	    }
-	}
-# endif
-    }
-
-  return 0;
-}
-#endif
-
-
 void *
-__nss_lookup_function (service_user *ni, const char *fct_name)
-{
-  void **found, *result;
-
-  /* We now modify global data.  Protect it.  */
-  __libc_lock_lock (lock);
-
-  /* Search the tree of functions previously requested.  Data in the
-     tree are `known_function' structures, whose first member is a
-     `const char *', the lookup key.  The search returns a pointer to
-     the tree node structure; the first member of the is a pointer to
-     our structure (i.e. what will be a `known_function'); since the
-     first member of that is the lookup key string, &FCT_NAME is close
-     enough to a pointer to our structure to use as a lookup key that
-     will be passed to `known_compare' (above).  */
-
-  found = __tsearch (&fct_name, &ni->known, &known_compare);
-  if (found == NULL)
-    /* This means out-of-memory.  */
-    result = NULL;
-  else if (*found != &fct_name)
-    {
-      /* The search found an existing structure in the tree.  */
-      result = ((known_function *) *found)->fct_ptr;
-#ifdef PTR_DEMANGLE
-      PTR_DEMANGLE (result);
-#endif
-    }
-  else
-    {
-      /* This name was not known before.  Now we have a node in the tree
-	 (in the proper sorted position for FCT_NAME) that points to
-	 &FCT_NAME instead of any real `known_function' structure.
-	 Allocate a new structure and fill it in.  */
-
-      known_function *known = malloc (sizeof *known);
-      if (! known)
-	{
-#if !defined DO_STATIC_NSS || defined SHARED
-	remove_from_tree:
-#endif
-	  /* Oops.  We can't instantiate this node properly.
-	     Remove it from the tree.  */
-	  __tdelete (&fct_name, &ni->known, &known_compare);
-	  free (known);
-	  result = NULL;
-	}
-      else
-	{
-	  /* Point the tree node at this new structure.  */
-	  *found = known;
-	  known->fct_name = fct_name;
-
-#if !defined DO_STATIC_NSS || defined SHARED
-	  /* Load the appropriate library.  */
-	  if (nss_load_library (ni) != 0)
-	    /* This only happens when out of memory.  */
-	    goto remove_from_tree;
-
-	  if (ni->library->lib_handle == (void *) -1l)
-	    /* Library not found => function not found.  */
-	    result = NULL;
-	  else
-	    {
-	      /* Get the desired function.  */
-	      size_t namlen = (5 + strlen (ni->name) + 1
-			       + strlen (fct_name) + 1);
-	      char name[namlen];
-
-	      /* Construct the function name.  */
-	      __stpcpy (__stpcpy (__stpcpy (__stpcpy (name, "_nss_"),
-					    ni->name),
-				  "_"),
-			fct_name);
-
-	      /* Look up the symbol.  */
-	      result = __libc_dlsym (ni->library->lib_handle, name);
-	    }
-#else
-	  /* We can't get function address dynamically in static linking. */
-	  {
-# define DEFINE_ENT(h,nm)						      \
-	    { #h"_get"#nm"ent_r", _nss_##h##_get##nm##ent_r },		      \
-	    { #h"_end"#nm"ent", _nss_##h##_end##nm##ent },		      \
-	    { #h"_set"#nm"ent", _nss_##h##_set##nm##ent },
-# define DEFINE_GET(h,nm)						      \
-	    { #h"_get"#nm"_r", _nss_##h##_get##nm##_r },
-# define DEFINE_GETBY(h,nm,ky)						      \
-	    { #h"_get"#nm"by"#ky"_r", _nss_##h##_get##nm##by##ky##_r },
-	    static struct fct_tbl { const char *fname; void *fp; } *tp, tbl[] =
-	      {
-# include "function.def"
-		{ NULL, NULL }
-	      };
-	    size_t namlen = (5 + strlen (ni->name) + 1
-			     + strlen (fct_name) + 1);
-	    char name[namlen];
-
-	    /* Construct the function name.  */
-	    __stpcpy (__stpcpy (__stpcpy (name, ni->name),
-				"_"),
-		      fct_name);
-
-	    result = NULL;
-	    for (tp = &tbl[0]; tp->fname; tp++)
-	      if (strcmp (tp->fname, name) == 0)
-		{
-		  result = tp->fp;
-		  break;
-		}
-	  }
-#endif
-
-	  /* Remember function pointer for later calls.  Even if null, we
-	     record it so a second try needn't search the library again.  */
-	  known->fct_ptr = result;
-#ifdef PTR_MANGLE
-	  PTR_MANGLE (known->fct_ptr);
-#endif
-	}
-    }
-
-  /* Remove the lock.  */
-  __libc_lock_unlock (lock);
-
-  return result;
-}
-libc_hidden_def (__nss_lookup_function)
-
-
-static name_database *
-nss_parse_file (const char *fname)
+__nss_lookup_function (nss_action_list ni, const char *fct_name)
 {
-  FILE *fp;
-  name_database *result;
-  name_database_entry *last;
-  char *line;
-  size_t len;
-
-  /* Open the configuration file.  */
-  fp = fopen (fname, "rce");
-  if (fp == NULL)
+  if (ni->module == NULL)
     return NULL;
-
-  /* No threads use this stream.  */
-  __fsetlocking (fp, FSETLOCKING_BYCALLER);
-
-  result = (name_database *) malloc (sizeof (name_database));
-  if (result == NULL)
-    {
-      fclose (fp);
-      return NULL;
-    }
-
-  result->entry = NULL;
-  result->library = NULL;
-  last = NULL;
-  line = NULL;
-  len = 0;
-  do
-    {
-      name_database_entry *this;
-      ssize_t n;
-
-      n = __getline (&line, &len, fp);
-      if (n < 0)
-	break;
-      if (line[n - 1] == '\n')
-	line[n - 1] = '\0';
-
-      /* Because the file format does not know any form of quoting we
-	 can search forward for the next '#' character and if found
-	 make it terminating the line.  */
-      *__strchrnul (line, '#') = '\0';
-
-      /* If the line is blank it is ignored.  */
-      if (line[0] == '\0')
-	continue;
-
-      /* Each line completely specifies the actions for a database.  */
-      this = nss_getline (line);
-      if (this != NULL)
-	{
-	  if (last != NULL)
-	    last->next = this;
-	  else
-	    result->entry = this;
-
-	  last = this;
-	}
-    }
-  while (!__feof_unlocked (fp));
-
-  /* Free the buffer.  */
-  free (line);
-  /* Close configuration file.  */
-  fclose (fp);
-
-  return result;
-}
-
-
-/* Read the source names:
-	`( <source> ( "[" "!"? (<status> "=" <action> )+ "]" )? )*'
-   */
-static service_user *
-nss_parse_service_list (const char *line)
-{
-  service_user *result = NULL, **nextp = &result;
-
-  while (1)
-    {
-      service_user *new_service;
-      const char *name;
-
-      while (isspace (line[0]))
-	++line;
-      if (line[0] == '\0')
-	/* No source specified.  */
-	return result;
-
-      /* Read <source> identifier.  */
-      name = line;
-      while (line[0] != '\0' && !isspace (line[0]) && line[0] != '[')
-	++line;
-      if (name == line)
-	return result;
-
-
-      new_service = (service_user *) malloc (sizeof (service_user)
-					     + (line - name + 1));
-      if (new_service == NULL)
-	return result;
-
-      *((char *) __mempcpy (new_service->name, name, line - name)) = '\0';
-
-      /* Set default actions.  */
-      new_service->actions[2 + NSS_STATUS_TRYAGAIN] = NSS_ACTION_CONTINUE;
-      new_service->actions[2 + NSS_STATUS_UNAVAIL] = NSS_ACTION_CONTINUE;
-      new_service->actions[2 + NSS_STATUS_NOTFOUND] = NSS_ACTION_CONTINUE;
-      new_service->actions[2 + NSS_STATUS_SUCCESS] = NSS_ACTION_RETURN;
-      new_service->actions[2 + NSS_STATUS_RETURN] = NSS_ACTION_RETURN;
-      new_service->library = NULL;
-      new_service->known = NULL;
-      new_service->next = NULL;
-
-      while (isspace (line[0]))
-	++line;
-
-      if (line[0] == '[')
-	{
-	  /* Read criterions.  */
-	  do
-	    ++line;
-	  while (line[0] != '\0' && isspace (line[0]));
-
-	  do
-	    {
-	      int not;
-	      enum nss_status status;
-	      lookup_actions action;
-
-	      /* Grok ! before name to mean all statii but that one.  */
-	      not = line[0] == '!';
-	      if (not)
-		++line;
-
-	      /* Read status name.  */
-	      name = line;
-	      while (line[0] != '\0' && !isspace (line[0]) && line[0] != '='
-		     && line[0] != ']')
-		++line;
-
-	      /* Compare with known statii.  */
-	      if (line - name == 7)
-		{
-		  if (__strncasecmp (name, "SUCCESS", 7) == 0)
-		    status = NSS_STATUS_SUCCESS;
-		  else if (__strncasecmp (name, "UNAVAIL", 7) == 0)
-		    status = NSS_STATUS_UNAVAIL;
-		  else
-		    goto finish;
-		}
-	      else if (line - name == 8)
-		{
-		  if (__strncasecmp (name, "NOTFOUND", 8) == 0)
-		    status = NSS_STATUS_NOTFOUND;
-		  else if (__strncasecmp (name, "TRYAGAIN", 8) == 0)
-		    status = NSS_STATUS_TRYAGAIN;
-		  else
-		    goto finish;
-		}
-	      else
-		goto finish;
-
-	      while (isspace (line[0]))
-		++line;
-	      if (line[0] != '=')
-		goto finish;
-	      do
-		++line;
-	      while (isspace (line[0]));
-
-	      name = line;
-	      while (line[0] != '\0' && !isspace (line[0]) && line[0] != '='
-		     && line[0] != ']')
-		++line;
-
-	      if (line - name == 6 && __strncasecmp (name, "RETURN", 6) == 0)
-		action = NSS_ACTION_RETURN;
-	      else if (line - name == 8
-		       && __strncasecmp (name, "CONTINUE", 8) == 0)
-		action = NSS_ACTION_CONTINUE;
-	      else if (line - name == 5
-		       && __strncasecmp (name, "MERGE", 5) == 0)
-		action = NSS_ACTION_MERGE;
-	      else
-		goto finish;
-
-	      if (not)
-		{
-		  /* Save the current action setting for this status,
-		     set them all to the given action, and reset this one.  */
-		  const lookup_actions save = new_service->actions[2 + status];
-		  new_service->actions[2 + NSS_STATUS_TRYAGAIN] = action;
-		  new_service->actions[2 + NSS_STATUS_UNAVAIL] = action;
-		  new_service->actions[2 + NSS_STATUS_NOTFOUND] = action;
-		  new_service->actions[2 + NSS_STATUS_SUCCESS] = action;
-		  new_service->actions[2 + status] = save;
-		}
-	      else
-		new_service->actions[2 + status] = action;
-
-	      /* Skip white spaces.  */
-	      while (isspace (line[0]))
-		++line;
-	    }
-	  while (line[0] != ']');
-
-	  /* Skip the ']'.  */
-	  ++line;
-	}
-
-      *nextp = new_service;
-      nextp = &new_service->next;
-      continue;
-
-    finish:
-      free (new_service);
-      return result;
-    }
-}
-
-static name_database_entry *
-nss_getline (char *line)
-{
-  const char *name;
-  name_database_entry *result;
-  size_t len;
-
-  /* Ignore leading white spaces.  ATTENTION: this is different from
-     what is implemented in Solaris.  The Solaris man page says a line
-     beginning with a white space character is ignored.  We regard
-     this as just another misfeature in Solaris.  */
-  while (isspace (line[0]))
-    ++line;
-
-  /* Recognize `<database> ":"'.  */
-  name = line;
-  while (line[0] != '\0' && !isspace (line[0]) && line[0] != ':')
-    ++line;
-  if (line[0] == '\0' || name == line)
-    /* Syntax error.  */
-    return NULL;
-  *line++ = '\0';
-
-  len = strlen (name) + 1;
-
-  result = (name_database_entry *) malloc (sizeof (name_database_entry) + len);
-  if (result == NULL)
-    return NULL;
-
-  /* Save the database name.  */
-  memcpy (result->name, name, len);
-
-  /* Parse the list of services.  */
-  result->service = nss_parse_service_list (line);
-
-  result->next = NULL;
-  return result;
-}
-
-
-#if !defined DO_STATIC_NSS || defined SHARED
-static service_library *
-nss_new_service (name_database *database, const char *name)
-{
-  service_library **currentp = &database->library;
-
-  while (*currentp != NULL)
-    {
-      if (strcmp ((*currentp)->name, name) == 0)
-	return *currentp;
-      currentp = &(*currentp)->next;
-    }
-
-  /* We have to add the new service.  */
-  *currentp = (service_library *) malloc (sizeof (service_library));
-  if (*currentp == NULL)
-    return NULL;
-
-  (*currentp)->name = name;
-  (*currentp)->lib_handle = NULL;
-  (*currentp)->next = NULL;
-
-  return *currentp;
-}
-#endif
-
-
-#if defined SHARED && defined USE_NSCD
-/* Load all libraries for the service.  */
-static void
-nss_load_all_libraries (const char *service, const char *def)
-{
-  service_user *ni = NULL;
-
-  if (__nss_database_lookup2 (service, NULL, def, &ni) == 0)
-    while (ni != NULL)
-      {
-	nss_load_library (ni);
-	ni = ni->next;
-      }
-}
-
-
-/* Called by nscd and nscd alone.  */
-void
-__nss_disable_nscd (void (*cb) (size_t, struct traced_file *))
-{
-# ifdef PTR_MANGLE
-  PTR_MANGLE (cb);
-# endif
-  nscd_init_cb = cb;
-  is_nscd = true;
-
-  /* Find all the relevant modules so that the init functions are called.  */
-  nss_load_all_libraries ("passwd", "files");
-  nss_load_all_libraries ("group", "files");
-  nss_load_all_libraries ("hosts", "dns [!UNAVAIL=return] files");
-  nss_load_all_libraries ("services", NULL);
-
-  /* Disable all uses of NSCD.  */
-  __nss_not_use_nscd_passwd = -1;
-  __nss_not_use_nscd_group = -1;
-  __nss_not_use_nscd_hosts = -1;
-  __nss_not_use_nscd_services = -1;
-  __nss_not_use_nscd_netgroup = -1;
-}
-#endif
-
-static void
-free_database_entries (name_database_entry *entry)
-{
-  while (entry != NULL)
-    {
-      name_database_entry *olde = entry;
-      service_user *service = entry->service;
-
-      while (service != NULL)
-	{
-	  service_user *olds = service;
-
-	  if (service->known != NULL)
-	    __tdestroy (service->known, free);
-
-	  service = service->next;
-	  free (olds);
-	}
-
-      entry = entry->next;
-      free (olde);
-    }
-}
-
-/* Free all resources if necessary.  */
-libc_freeres_fn (free_defconfig)
-{
-  name_database_entry *entry = defconfig_entries;
-
-  if (entry == NULL)
-    /* defconfig was not used.  */
-    return;
-
-  /* Don't disturb ongoing other threads (if there are any).  */
-  defconfig_entries = NULL;
-
-  free_database_entries (entry);
-}
-
-libc_freeres_fn (free_mem)
-{
-  name_database *top = service_table;
-  service_library *library;
-
-  if (top == NULL)
-    /* Maybe we have not read the nsswitch.conf file.  */
-    return;
-
-  /* Don't disturb ongoing other threads (if there are any).  */
-  service_table = NULL;
-
-  free_database_entries (top->entry);
-
-  library = top->library;
-  while (library != NULL)
-    {
-      service_library *oldl = library;
-
-      if (library->lib_handle && library->lib_handle != (void *) -1l)
-	__libc_dlclose (library->lib_handle);
-
-      library = library->next;
-      free (oldl);
-    }
-
-  free (top);
+  return __nss_module_get_function (ni->module, fct_name);
 }
+libc_hidden_def (__nss_lookup_function)
diff --git a/nss/nsswitch.h b/nss/nsswitch.h
index eaf81587d6..61b92a7115 100644
--- a/nss/nsswitch.h
+++ b/nss/nsswitch.h
@@ -36,6 +36,7 @@  typedef enum
   NSS_ACTION_MERGE
 } lookup_actions;
 
+struct nss_action;
 
 typedef struct service_library
 {
@@ -58,42 +59,8 @@  typedef struct
 } known_function;
 
 
-typedef struct service_user
-{
-  /* And the link to the next entry.  */
-  struct service_user *next;
-  /* Action according to result.  */
-  lookup_actions actions[5];
-  /* Link to the underlying library object.  */
-  service_library *library;
-  /* Collection of known functions.  */
-  void *known;
-  /* Name of the service (`files', `dns', `nis', ...).  */
-  char name[0];
-} service_user;
-
 /* To access the action based on the status value use this macro.  */
-#define nss_next_action(ni, status) ((ni)->actions[2 + status])
-
-
-typedef struct name_database_entry
-{
-  /* And the link to the next entry.  */
-  struct name_database_entry *next;
-  /* List of service to be used.  */
-  service_user *service;
-  /* Name of the database.  */
-  char name[0];
-} name_database_entry;
-
-
-typedef struct name_database
-{
-  /* List of all known databases.  */
-  name_database_entry *entry;
-  /* List of libraries with service implementation.  */
-  service_library *library;
-} name_database;
+#define nss_next_action(ni, status) nss_action_get (ni, status)
 
 
 #ifdef USE_NSCD
@@ -127,13 +94,13 @@  extern bool __nss_database_custom[NSS_DBSIDX_max] attribute_hidden;
    than one function can use the database.  */
 extern int __nss_database_lookup2 (const char *database,
 				   const char *alternative_name,
-				   const char *defconfig, service_user **ni);
+				   const char *defconfig, struct nss_action **ni);
 libc_hidden_proto (__nss_database_lookup2)
 
 /* Put first function with name FCT_NAME for SERVICE in FCTP.  The
    position is remembered in NI.  The function returns a value < 0 if
    an error occurred or no such function exists.  */
-extern int __nss_lookup (service_user **ni, const char *fct_name,
+extern int __nss_lookup (struct nss_action **ni, const char *fct_name,
 			 const char *fct2_name, void **fctp);
 libc_hidden_proto (__nss_lookup)
 
@@ -150,16 +117,16 @@  libc_hidden_proto (__nss_lookup)
    services.  In other words, only if all four lookup results have
    the action RETURN associated the lookup process stops before the
    natural end.  */
-extern int __nss_next2 (service_user **ni, const char *fct_name,
+extern int __nss_next2 (struct nss_action **ni, const char *fct_name,
 			const char *fct2_name, void **fctp, int status,
 			int all_values) attribute_hidden;
 libc_hidden_proto (__nss_next2)
-extern int __nss_next (service_user **ni, const char *fct_name, void **fctp,
+extern int __nss_next (struct nss_action **ni, const char *fct_name, void **fctp,
 		       int status, int all_values);
 
 /* Search for the service described in NI for a function named FCT_NAME
    and return a pointer to this function if successful.  */
-extern void *__nss_lookup_function (service_user *ni, const char *fct_name);
+extern void *__nss_lookup_function (struct nss_action *ni, const char *fct_name);
 libc_hidden_proto (__nss_lookup_function)
 
 
@@ -169,7 +136,7 @@  struct traced_file;
 extern void __nss_disable_nscd (void (*) (size_t, struct traced_file *));
 
 
-typedef int (*db_lookup_function) (service_user **, const char *, const char *,
+typedef int (*db_lookup_function) (struct nss_action **, const char *, const char *,
 				   void **);
 typedef enum nss_status (*setent_function) (int);
 typedef enum nss_status (*endent_function) (void);
@@ -180,20 +147,20 @@  typedef int (*getent_r_function) (void *, char *, size_t,
 
 extern void __nss_setent (const char *func_name,
 			  db_lookup_function lookup_fct,
-			  service_user **nip, service_user **startp,
-			  service_user **last_nip, int stayon,
+			  struct nss_action **nip, struct nss_action **startp,
+			  struct nss_action **last_nip, int stayon,
 			  int *stayon_tmp, int res)
      attribute_hidden;
 extern void __nss_endent (const char *func_name,
 			  db_lookup_function lookup_fct,
-			  service_user **nip, service_user **startp,
-			  service_user **last_nip, int res)
+			  struct nss_action **nip, struct nss_action **startp,
+			  struct nss_action **last_nip, int res)
      attribute_hidden;
 extern int __nss_getent_r (const char *getent_func_name,
 			   const char *setent_func_name,
 			   db_lookup_function lookup_fct,
-			   service_user **nip, service_user **startp,
-			   service_user **last_nip, int *stayon_tmp,
+			   struct nss_action **nip, struct nss_action **startp,
+			   struct nss_action **last_nip, int *stayon_tmp,
 			   int res,
 			   void *resbuf, char *buffer, size_t buflen,
 			   void **result, int *h_errnop)
@@ -227,11 +194,15 @@  libc_hidden_proto (__nss_hostname_digits_dots)
 
 /* Prototypes for __nss_*_lookup2 functions.  */
 #define DEFINE_DATABASE(arg)						      \
-  extern service_user *__nss_##arg##_database attribute_hidden;		      \
-  int __nss_##arg##_lookup2 (service_user **, const char *,		      \
+  extern struct nss_action *__nss_##arg##_database attribute_hidden;		      \
+  int __nss_##arg##_lookup2 (struct nss_action **, const char *,		      \
 			     const char *, void **);			      \
   libc_hidden_proto (__nss_##arg##_lookup2)
 #include "databases.def"
 #undef DEFINE_DATABASE
 
+#include <nss/nss_module.h>
+#include <nss/nss_action.h>
+#include <nss/nss_database.h>
+
 #endif	/* nsswitch.h */
diff --git a/nss/tst-reload1.c b/nss/tst-reload1.c
new file mode 100644
index 0000000000..8e6241382b
--- /dev/null
+++ b/nss/tst-reload1.c
@@ -0,0 +1,341 @@ 
+/* Test that nsswitch.conf reloading actually works.
+   Copyright (C) 2020 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <nss.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <errno.h>
+#include <pwd.h>
+
+#include <support/support.h>
+#include <support/check.h>
+
+#include "nss_test.h"
+
+/* Size of buffers used by *_r functions.  */
+#define TESTBUFLEN 4096
+
+static struct passwd pwd_table_1[] = {
+    PWD (100),
+    PWD (30),
+    PWD (200),
+    PWD (60),
+    PWD (20000),
+    PWD_LAST ()
+  };
+
+static const char *hostaddr_5[] =
+  {
+   "ABCD", "abcd", "1234", NULL
+  };
+
+static const char *hostaddr_15[] =
+  {
+   "4321", "ghij", NULL
+  };
+
+static const char *hostaddr_25[] =
+  {
+   "WXYZ", NULL
+  };
+
+
+static struct hostent host_table_1[] = {
+  HOST (5),
+  HOST (15),
+  HOST (25),
+  HOST_LAST ()
+};
+
+void
+_nss_test1_init_hook(test_tables *t)
+{
+  t->pwd_table = pwd_table_1;
+  t->host_table = host_table_1;
+}
+
+/* The first of these must not appear in pwd_table_1.  */
+static struct passwd pwd_table_2[] = {
+    PWD (5),
+    PWD_N(200, "name30"),
+    PWD (16),
+    PWD_LAST ()
+  };
+
+static const char *hostaddr_6[] =
+  {
+   "mnop", NULL
+  };
+
+static const char *hostaddr_16[] =
+  {
+   "7890", "a1b2", NULL
+  };
+
+static const char *hostaddr_26[] =
+  {
+   "qwer", "tyui", NULL
+  };
+
+static struct hostent host_table_2[] = {
+  HOST (6),
+  HOST (16),
+  HOST (26),
+  HOST_LAST ()
+};
+
+void
+_nss_test2_init_hook(test_tables *t)
+{
+  t->pwd_table = pwd_table_2;
+  t->host_table = host_table_2;
+}
+
+static void
+must_be_tests (struct passwd *pt, struct hostent *ht)
+{
+  int i;
+  struct hostent *h;
+
+  struct passwd *p;
+  for (i = 0; !PWD_ISLAST (&pt[i]); ++ i)
+    {
+      p = getpwuid (pt[i].pw_uid);
+      TEST_VERIFY (p != NULL);
+      if (p != NULL)
+	{
+	  TEST_VERIFY (strcmp (p->pw_name, pt[i].pw_name) == 0);
+	}
+    }
+
+  setpwent ();
+  for (i = 0; !PWD_ISLAST (&pt[i]); ++ i)
+    {
+      p = getpwent ();
+      TEST_VERIFY (p != NULL);
+      if (p != NULL)
+	{
+	  TEST_VERIFY (strcmp (p->pw_name, pt[i].pw_name) == 0);
+	  TEST_VERIFY (p->pw_uid == pt[i].pw_uid);
+	}
+    }
+  endpwent ();
+
+  for (i = 0; !HOST_ISLAST (&ht[i]); ++ i)
+    {
+      h = gethostbyname (ht[i].h_name);
+      TEST_VERIFY (h != NULL);
+      if (h != NULL)
+	{
+	  TEST_VERIFY (strcmp (h->h_name, ht[i].h_name) == 0);
+	  TEST_VERIFY (h->h_addr_list[0] != NULL);
+	  if (h->h_addr_list[0])
+	    TEST_VERIFY (strcmp (h->h_addr_list[0], ht[i].h_addr_list[0]) == 0);
+	}
+    }
+
+  for (i = 0; !HOST_ISLAST (&ht[i]); ++ i)
+    {
+      struct hostent r, *rp;
+      char buf[TESTBUFLEN];
+      int herrno, res;
+
+      res = gethostbyname2_r (ht[i].h_name, AF_INET,
+			    &r, buf, TESTBUFLEN, &rp, &herrno);
+      TEST_VERIFY (res == 0);
+      if (res == 0)
+	{
+	  TEST_VERIFY (strcmp (r.h_name, ht[i].h_name) == 0);
+	  TEST_VERIFY (r.h_addr_list[0] != NULL);
+	  if (r.h_addr_list[0])
+	    TEST_VERIFY (strcmp (r.h_addr_list[0], ht[i].h_addr_list[0]) == 0);
+	}
+    }
+
+  for (i = 0; !HOST_ISLAST (&ht[i]); ++ i)
+    {
+      h = gethostbyaddr (ht[i].h_addr, 4, AF_INET);
+      TEST_VERIFY (h != NULL);
+      if (h != NULL)
+	{
+	  TEST_VERIFY (strcmp (h->h_name, ht[i].h_name) == 0);
+	  TEST_VERIFY (h->h_addr_list[0] != NULL);
+	  if (h->h_addr_list[0])
+	    TEST_VERIFY (strcmp (h->h_addr_list[0], ht[i].h_addr_list[0]) == 0);
+	}
+    }
+
+  /* getaddrinfo */
+
+  for (i = 0; !HOST_ISLAST (&ht[i]); ++ i)
+    {
+      struct addrinfo *ap;
+      struct addrinfo hint;
+      int res, j;
+
+      memset (&hint, 0, sizeof (hint));
+      hint.ai_family = AF_INET;
+      hint.ai_socktype = SOCK_STREAM;
+      hint.ai_protocol = 0;
+      hint.ai_flags = 0;
+
+      ap = NULL;
+      res = getaddrinfo (ht[i].h_name, NULL, &hint, &ap);
+      TEST_VERIFY (res == 0);
+      TEST_VERIFY (ap != NULL);
+      if (res == 0 && ap != NULL)
+	{
+	  j = 0; /* which address in the list */
+	  while (ap)
+	    {
+	      struct sockaddr_in *in = (struct sockaddr_in *)ap->ai_addr;
+	      unsigned char *up = (unsigned char *)&in->sin_addr;
+
+	      TEST_VERIFY (memcmp (up, ht[i].h_addr_list[j], 4) == 0);
+
+	      ap = ap->ai_next;
+	      ++ j;
+	    }
+	}
+    }
+
+  /* getnameinfo */
+
+  for (i = 0; !HOST_ISLAST (&ht[i]); ++ i)
+    {
+      struct sockaddr_in addr;
+      int res;
+      char host_buf[NI_MAXHOST];
+
+      memset (&addr, 0, sizeof (addr));
+      addr.sin_family = AF_INET;
+      addr.sin_port = 80;
+      memcpy (& addr.sin_addr, ht[i].h_addr_list[0], 4);
+
+      res = getnameinfo ((struct sockaddr *) &addr, sizeof(addr),
+			 host_buf, sizeof(host_buf),
+			 NULL, 0, NI_NOFQDN);
+
+      TEST_VERIFY (res == 0);
+      if (res == 0)
+	TEST_VERIFY (strcmp (ht[i].h_name, host_buf) == 0);
+      else
+	printf ("error %s\n", gai_strerror (res));
+    }
+}
+
+static void
+must_be_1 (void)
+{
+  struct passwd *p;
+
+  must_be_tests (pwd_table_1, host_table_1);
+  p = getpwnam("name5");
+  TEST_VERIFY (p == NULL);
+}
+
+static void
+must_be_2 (void)
+{
+  struct passwd *p;
+
+  must_be_tests (pwd_table_2, host_table_2);
+  p = getpwnam("name100");
+  TEST_VERIFY (p == NULL);
+}
+
+static void
+xrename (const char *a, const char *b)
+{
+  int i = rename (a, b);
+  if (i != 0)
+    FAIL_EXIT1 ("rename(%s,%s) failed: %s\n", a, b, strerror(errno));
+}
+
+/* If the actions change while in the midst of doing a series of
+   lookups, make sure they're consistent.  */
+static void
+test_cross_switch_consistency (void)
+{
+  int i;
+  struct passwd *p;
+
+  /* We start by initiating a set/get/end loop on conf1.  */
+  setpwent ();
+  for (i = 0; !PWD_ISLAST (&pwd_table_1[i]); ++ i)
+    {
+      p = getpwent ();
+      TEST_VERIFY (p != NULL);
+      if (p != NULL)
+	{
+	  TEST_VERIFY (strcmp (p->pw_name, pwd_table_1[i].pw_name) == 0);
+	  TEST_VERIFY (p->pw_uid == pwd_table_1[i].pw_uid);
+	}
+
+      /* After the first lookup, switch to conf2 and verify */
+      if (i == 0)
+	{
+	  xrename ("/etc/nsswitch.conf", "/etc/nsswitch.conf1");
+	  xrename ("/etc/nsswitch.conf2", "/etc/nsswitch.conf");
+
+	  p = getpwnam (pwd_table_2[0].pw_name);
+	  TEST_VERIFY (p->pw_uid == pwd_table_2[0].pw_uid);
+	}
+
+      /* But the original loop should still be on conf1.  */
+    }
+  endpwent ();
+
+  /* Make sure the set/get/end loop sees conf2 now.  */
+  setpwent ();
+  for (i = 0; !PWD_ISLAST (&pwd_table_2[i]); ++ i)
+    {
+      p = getpwent ();
+      TEST_VERIFY (p != NULL);
+      if (p != NULL)
+	{
+	  TEST_VERIFY (strcmp (p->pw_name, pwd_table_2[i].pw_name) == 0);
+	  TEST_VERIFY (p->pw_uid == pwd_table_2[i].pw_uid);
+	}
+    }
+  endpwent ();
+ 
+}
+
+static int
+do_test (void)
+{
+  /* The test1 module was configured at program start.  */
+  must_be_1 ();
+
+  xrename ("/etc/nsswitch.conf", "/etc/nsswitch.conf1");
+  xrename ("/etc/nsswitch.conf2", "/etc/nsswitch.conf");
+  must_be_2 ();
+
+  xrename ("/etc/nsswitch.conf", "/etc/nsswitch.conf2");
+  xrename ("/etc/nsswitch.conf1", "/etc/nsswitch.conf");
+  must_be_1 ();
+
+  test_cross_switch_consistency ();
+
+  return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/nss/tst-reload1.root/etc/nsswitch.conf b/nss/tst-reload1.root/etc/nsswitch.conf
new file mode 100644
index 0000000000..606d8f51d6
--- /dev/null
+++ b/nss/tst-reload1.root/etc/nsswitch.conf
@@ -0,0 +1,3 @@ 
+passwd:	test1
+group:	test1
+hosts:	test1
diff --git a/nss/tst-reload1.root/etc/nsswitch.conf2 b/nss/tst-reload1.root/etc/nsswitch.conf2
new file mode 100644
index 0000000000..2e93977efb
--- /dev/null
+++ b/nss/tst-reload1.root/etc/nsswitch.conf2
@@ -0,0 +1,3 @@ 
+passwd:	test2
+group:	test2
+hosts:	test2
diff --git a/nss/tst-reload1.root/etc/services b/nss/tst-reload1.root/etc/services
new file mode 100644
index 0000000000..94d4f07612
--- /dev/null
+++ b/nss/tst-reload1.root/etc/services
@@ -0,0 +1 @@ 
+http 80/tcp
diff --git a/nss/tst-reload1.root/tst-reload1.script b/nss/tst-reload1.root/tst-reload1.script
new file mode 100644
index 0000000000..a10beb1e6c
--- /dev/null
+++ b/nss/tst-reload1.root/tst-reload1.script
@@ -0,0 +1,2 @@ 
+cp $B/nss/libnss_test1.so $L/libnss_test1.so.2
+cp $B/nss/libnss_test2.so $L/libnss_test2.so.2
diff --git a/posix/tst-rfc3484-2.c b/posix/tst-rfc3484-2.c
index 8c64ac59ff..5f5ada9420 100644
--- a/posix/tst-rfc3484-2.c
+++ b/posix/tst-rfc3484-2.c
@@ -58,7 +58,7 @@  _res_hconf_init (void)
 #undef	USE_NSCD
 #include "../sysdeps/posix/getaddrinfo.c"
 
-service_user *__nss_hosts_database attribute_hidden;
+nss_action_list __nss_hosts_database attribute_hidden;
 
 /* This is the beginning of the real test code.  The above defines
    (among other things) the function rfc3484_sort.  */
diff --git a/posix/tst-rfc3484-3.c b/posix/tst-rfc3484-3.c
index 1c61aaf844..d9ec5cc851 100644
--- a/posix/tst-rfc3484-3.c
+++ b/posix/tst-rfc3484-3.c
@@ -58,7 +58,7 @@  _res_hconf_init (void)
 #undef	USE_NSCD
 #include "../sysdeps/posix/getaddrinfo.c"
 
-service_user *__nss_hosts_database attribute_hidden;
+nss_action_list __nss_hosts_database attribute_hidden;
 
 /* This is the beginning of the real test code.  The above defines
    (among other things) the function rfc3484_sort.  */
diff --git a/posix/tst-rfc3484.c b/posix/tst-rfc3484.c
index 8f45848e44..97d065b6bf 100644
--- a/posix/tst-rfc3484.c
+++ b/posix/tst-rfc3484.c
@@ -58,7 +58,7 @@  _res_hconf_init (void)
 #undef	USE_NSCD
 #include "../sysdeps/posix/getaddrinfo.c"
 
-service_user *__nss_hosts_database attribute_hidden;
+nss_action_list __nss_hosts_database attribute_hidden;
 
 /* This is the beginning of the real test code.  The above defines
    (among other things) the function rfc3484_sort.  */
diff --git a/sunrpc/netname.c b/sunrpc/netname.c
index 61d82ca31a..aa64362b4b 100644
--- a/sunrpc/netname.c
+++ b/sunrpc/netname.c
@@ -145,9 +145,7 @@  int
 netname2user (const char netname[MAXNETNAMELEN + 1], uid_t * uidp, gid_t * gidp,
 	      int *gidlenp, gid_t * gidlist)
 {
-  static service_user *startp;
-  static netname2user_function start_fct;
-  service_user *nip;
+  nss_action_list nip;
   union
   {
     netname2user_function f;
@@ -156,22 +154,7 @@  netname2user (const char netname[MAXNETNAMELEN + 1], uid_t * uidp, gid_t * gidp,
   enum nss_status status = NSS_STATUS_UNAVAIL;
   int no_more;
 
-  if (startp == NULL)
-    {
-      no_more = __nss_publickey_lookup2 (&nip, "netname2user", NULL, &fct.ptr);
-      if (no_more)
-	startp = (service_user *) - 1;
-      else
-	{
-	  startp = nip;
-	  start_fct = fct.f;
-	}
-    }
-  else
-    {
-      fct.f = start_fct;
-      no_more = (nip = startp) == (service_user *) - 1;
-    }
+  no_more = __nss_publickey_lookup2 (&nip, "netname2user", NULL, &fct.ptr);
 
   while (!no_more)
     {
diff --git a/sunrpc/publickey.c b/sunrpc/publickey.c
index 2fa0252d5b..63866ef900 100644
--- a/sunrpc/publickey.c
+++ b/sunrpc/publickey.c
@@ -34,9 +34,7 @@  typedef int (*secret_function) (const char *, char *, const char *, int *);
 int
 getpublickey (const char *name, char *key)
 {
-  static service_user *startp;
-  static public_function start_fct;
-  service_user *nip;
+  nss_action_list nip;
   union
   {
     public_function f;
@@ -45,22 +43,7 @@  getpublickey (const char *name, char *key)
   enum nss_status status = NSS_STATUS_UNAVAIL;
   int no_more;
 
-  if (startp == NULL)
-    {
-      no_more = __nss_publickey_lookup2 (&nip, "getpublickey", NULL, &fct.ptr);
-      if (no_more)
-	startp = (service_user *) -1;
-      else
-	{
-	  startp = nip;
-	  start_fct = fct.f;
-	}
-    }
-  else
-    {
-      fct.f = start_fct;
-      no_more = (nip = startp) == (service_user *) -1;
-    }
+  no_more = __nss_publickey_lookup2 (&nip, "getpublickey", NULL, &fct.ptr);
 
   while (! no_more)
     {
@@ -77,9 +60,7 @@  libc_hidden_nolink_sunrpc (getpublickey, GLIBC_2_0)
 int
 getsecretkey (const char *name, char *key, const char *passwd)
 {
-  static service_user *startp;
-  static secret_function start_fct;
-  service_user *nip;
+  nss_action_list nip;
   union
   {
     secret_function f;
@@ -88,22 +69,7 @@  getsecretkey (const char *name, char *key, const char *passwd)
   enum nss_status status = NSS_STATUS_UNAVAIL;
   int no_more;
 
-  if (startp == NULL)
-    {
-      no_more = __nss_publickey_lookup2 (&nip, "getsecretkey", NULL, &fct.ptr);
-      if (no_more)
-	startp = (service_user *) -1;
-      else
-	{
-	  startp = nip;
-	  start_fct = fct.f;
-	}
-    }
-  else
-    {
-      fct.f = start_fct;
-      no_more = (nip = startp) == (service_user *) -1;
-    }
+  no_more = __nss_publickey_lookup2 (&nip, "getsecretkey", NULL, &fct.ptr);
 
   while (! no_more)
     {
diff --git a/sysdeps/posix/getaddrinfo.c b/sysdeps/posix/getaddrinfo.c
index ed04e564f9..39e54fc741 100644
--- a/sysdeps/posix/getaddrinfo.c
+++ b/sysdeps/posix/getaddrinfo.c
@@ -307,7 +307,7 @@  convert_hostent_to_gaih_addrtuple (const struct addrinfo *req,
    memory allocation failure.  The returned string is allocated on the
    heap; the caller has to free it.  */
 static char *
-getcanonname (service_user *nip, struct gaih_addrtuple *at, const char *name)
+getcanonname (nss_action_list nip, struct gaih_addrtuple *at, const char *name)
 {
   nss_getcanonname_r *cfct = __nss_lookup_function (nip, "getcanonname_r");
   char *s = (char *) name;
@@ -538,7 +538,7 @@  gaih_inet (const char *name, const struct gaih_service *service,
 	  struct gaih_addrtuple **pat = &at;
 	  int no_data = 0;
 	  int no_inet6_data = 0;
-	  service_user *nip;
+	  nss_action_list nip;
 	  enum nss_status inet6_status = NSS_STATUS_UNAVAIL;
 	  enum nss_status status = NSS_STATUS_UNAVAIL;
 	  int no_more;
@@ -720,13 +720,9 @@  gaih_inet (const char *name, const struct gaih_service *service,
 	    }
 #endif
 
-	  if (__nss_hosts_database == NULL)
-	    no_more = __nss_database_lookup2 ("hosts", NULL,
-					      "dns [!UNAVAIL=return] files",
-					      &__nss_hosts_database);
-	  else
-	    no_more = 0;
-	  nip = __nss_hosts_database;
+	  no_more = __nss_database_lookup2 ("hosts", NULL,
+					    "dns [!UNAVAIL=return] files",
+					    &nip);
 
 	  /* If we are looking for both IPv4 and IPv6 address we don't
 	     want the lookup functions to automatically promote IPv4
@@ -905,10 +901,9 @@  gaih_inet (const char *name, const struct gaih_service *service,
 	      if (nss_next_action (nip, status) == NSS_ACTION_RETURN)
 		break;
 
-	      if (nip->next == NULL)
+	      nip ++;
+	      if (nip->module == NULL)
 		no_more = -1;
-	      else
-		nip = nip->next;
 	    }
 
 	  __resolv_context_put (res_ctx);