/* Copyright (C) 1996-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.  */

#include <errno.h>

#include <libc-lock.h>

#include "nsswitch.h"

/*******************************************************************\

|* Here we assume several symbols to be defined:		   *|

|* 								   *|

|* LOOKUP_TYPE   - the return type of the function		   *|

|* 								   *|

|* SETFUNC_NAME  - name of the non-reentrant setXXXent function	   *|

|* 								   *|

|* GETFUNC_NAME  - name of the non-reentrant getXXXent function	   *|

|* 								   *|

|* ENDFUNC_NAME  - name of the non-reentrant endXXXent function	   *|

|* 								   *|

|* DATABASE_NAME - name of the database the function accesses	   *|

|*		   (e.g., host, services, ...)			   *|

|* 								   *|

|* Optionally the following vars can be defined:		   *|

|* 								   *|

|* STAYOPEN      - variable declaration for setXXXent function	   *|

|* 								   *|

|* STAYOPEN_VAR  - variable name for setXXXent function		   *|

|* 								   *|

|* NEED_H_ERRNO  - an extra parameter will be passed to point to   *|

|*		   the global `h_errno' variable.		   *|

|* 								   *|

\*******************************************************************/

/* To make the real sources a bit prettier.  */

#define REENTRANT_GETNAME APPEND_R (GETFUNC_NAME)

#define APPEND_R(Name) CONCAT2_2 (Name, _r)

#define INTERNAL(Name) CONCAT2_2 (__, Name)

#define CONCAT2_1(Pre, Post) CONCAT2_2 (Pre, Post)

#define CONCAT2_2(Pre, Post) Pre##Post

#define NEW(name) NEW1 (name)

#define NEW1(name) __new_##name

#define SETFUNC_NAME_STRING STRINGIZE (SETFUNC_NAME)

#define GETFUNC_NAME_STRING STRINGIZE (REENTRANT_GETNAME)

#define ENDFUNC_NAME_STRING STRINGIZE (ENDFUNC_NAME)

#define DATABASE_NAME_STRING STRINGIZE (DATABASE_NAME)

#define STRINGIZE(Name) STRINGIZE1 (Name)

#define STRINGIZE1(Name) #Name

#ifndef DB_LOOKUP_FCT

# define DB_LOOKUP_FCT CONCAT3_1 (__nss_, DATABASE_NAME, _lookup2)

# define CONCAT3_1(Pre, Name, Post) CONCAT3_2 (Pre, Name, Post)

# define CONCAT3_2(Pre, Name, Post) Pre##Name##Post

#endif

/* Sometimes we need to store error codes in the `h_errno' variable.  */

#ifdef NEED_H_ERRNO

# define H_ERRNO_PARM , int *h_errnop

# define H_ERRNO_VAR , &h_errno

# define H_ERRNO_VAR_P &h_errno

#else

# define H_ERRNO_PARM

# define H_ERRNO_VAR

# define H_ERRNO_VAR_P NULL

#endif

/* Some databases take the `stayopen' flag.  */

#ifdef STAYOPEN

# define STAYOPEN_TMP CONCAT2_1 (STAYOPEN, _tmp)

# define STAYOPEN_TMPVAR &CONCAT2_1 (STAYOPEN_VAR, _tmp)

#else

# define STAYOPEN void

# define STAYOPEN_VAR 0

# define STAYOPEN_TMPVAR NULL

#endif

#ifndef NEED__RES

# define NEED__RES 0

#endif

/* This handle for the NSS data base is shared between all

   set/get/endXXXent functions.  */

static service_user *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;

#ifdef STAYOPEN_TMP

/* We need to remember the last `stayopen' flag given by the user

   since the `setent' function is only called for the first available

   service.  */

static STAYOPEN_TMP;

#endif

/* Protect above variable against multiple uses at the same time.  */

__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,

			  const char *name2, void **fctp);

libc_hidden_proto (DB_LOOKUP_FCT)

void

SETFUNC_NAME (STAYOPEN)

{

  int save;

  __libc_lock_lock (lock);

  __nss_setent (SETFUNC_NAME_STRING, DB_LOOKUP_FCT, &nip, &startp,

		&last_nip, STAYOPEN_VAR, STAYOPEN_TMPVAR, NEED__RES);

  save = errno;

  __libc_lock_unlock (lock);

  __set_errno (save);

}

void

ENDFUNC_NAME (void)

{

  int save;

  /* If the service has not been used before do not do anything.  */

  if (startp != NULL)

    {

      __libc_lock_lock (lock);

      __nss_endent (ENDFUNC_NAME_STRING, DB_LOOKUP_FCT, &nip, &startp,

		    &last_nip, NEED__RES);

      save = errno;

      __libc_lock_unlock (lock);

      __set_errno (save);

    }

}

int

INTERNAL (REENTRANT_GETNAME) (LOOKUP_TYPE *resbuf, char *buffer, size_t buflen,

			      LOOKUP_TYPE **result H_ERRNO_PARM)

{

  int status;

  int save;

  __libc_lock_lock (lock);

  status = __nss_getent_r (GETFUNC_NAME_STRING, SETFUNC_NAME_STRING,

			   DB_LOOKUP_FCT, &nip, &startp, &last_nip,

			   STAYOPEN_TMPVAR, NEED__RES, resbuf, buffer,

			   buflen, (void **) result, H_ERRNO_VAR_P);

  save = errno;

  __libc_lock_unlock (lock);

  __set_errno (save);

  return status;

}

#ifdef NO_COMPAT_NEEDED

strong_alias (INTERNAL (REENTRANT_GETNAME), REENTRANT_GETNAME);

#else

# include <shlib-compat.h>

# if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1_2)

#  define OLD(name) OLD1 (name)

#  define OLD1(name) __old_##name

int

attribute_compat_text_section

OLD (REENTRANT_GETNAME) (LOOKUP_TYPE *resbuf, char *buffer, size_t buflen,

			 LOOKUP_TYPE **result H_ERRNO_PARM)

{

  int ret = INTERNAL (REENTRANT_GETNAME) (resbuf, buffer, buflen,

					  result H_ERRNO_VAR);

  if (ret != 0)

    ret = -1;

  return ret;

}

#  define do_symbol_version(real, name, version) \

  compat_symbol (libc, real, name, version)

do_symbol_version (OLD (REENTRANT_GETNAME), REENTRANT_GETNAME, GLIBC_2_0);

# endif

/* As INTERNAL (REENTRANT_GETNAME) may be hidden, we need an alias

   in between so that the REENTRANT_GETNAME@@GLIBC_2.1.2 is not

   hidden too.  */

strong_alias (INTERNAL (REENTRANT_GETNAME), NEW (REENTRANT_GETNAME));

# define do_default_symbol_version(real, name, version) \

  versioned_symbol (libc, real, name, version)

do_default_symbol_version (NEW (REENTRANT_GETNAME),

			   REENTRANT_GETNAME, GLIBC_2_1_2);

#endif

nss_interface_function (SETFUNC_NAME)

nss_interface_function (ENDFUNC_NAME)

nss_interface_function (REENTRANT_GETNAME)