nss/getXXent_r.c

   1 /* Copyright (C) 1996,97,98,99,2000 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <errno.h>
  21 #include <bits/libc-lock.h>
  22
  23 #include "nsswitch.h"
  24
  25 /*******************************************************************\
  26 |* Here we assume several symbols to be defined:                   *|
  27 |*                                                                 *|
  28 |* LOOKUP_TYPE   - the return type of the function                 *|
  29 |*                                                                 *|
  30 |* SETFUNC_NAME  - name of the non-reentrant setXXXent function    *|
  31 |*                                                                 *|
  32 |* GETFUNC_NAME  - name of the non-reentrant getXXXent function    *|
  33 |*                                                                 *|
  34 |* ENDFUNC_NAME  - name of the non-reentrant endXXXent function    *|
  35 |*                                                                 *|
  36 |* DATABASE_NAME - name of the database the function accesses      *|
  37 |*                 (e.g., host, services, ...)                     *|
  38 |*                                                                 *|
  39 |* Optionally the following vars can be defined:                   *|
  40 |*                                                                 *|
  41 |* STAYOPEN      - variable declaration for setXXXent function     *|
  42 |*                                                                 *|
  43 |* STAYOPEN_VAR  - variable name for setXXXent function            *|
  44 |*                                                                 *|
  45 |* NEED_H_ERRNO  - an extra parameter will be passed to point to   *|
  46 |*                 the global `h_errno' variable.                  *|
  47 |*                                                                 *|
  48 \*******************************************************************/
  49
  50 /* To make the real sources a bit prettier.  */
  51 #define REENTRANT_GETNAME APPEND_R (GETFUNC_NAME)
  52 #define APPEND_R(Name) CONCAT2_2 (Name, _r)
  53 #define INTERNAL(Name) CONCAT2_2 (__, Name)
  54 #define CONCAT2_1(Pre, Post) CONCAT2_2 (Pre, Post)
  55 #define CONCAT2_2(Pre, Post) Pre##Post
  56
  57 #define SETFUNC_NAME_STRING STRINGIZE (SETFUNC_NAME)
  58 #define GETFUNC_NAME_STRING STRINGIZE (REENTRANT_GETNAME)
  59 #define ENDFUNC_NAME_STRING STRINGIZE (ENDFUNC_NAME)
  60 #define DATABASE_NAME_STRING STRINGIZE (DATABASE_NAME)
  61 #define STRINGIZE(Name) STRINGIZE1 (Name)
  62 #define STRINGIZE1(Name) #Name
  63
  64 #define DB_LOOKUP_FCT CONCAT3_1 (__nss_, DATABASE_NAME, _lookup)
  65 #define CONCAT3_1(Pre, Name, Post) CONCAT3_2 (Pre, Name, Post)
  66 #define CONCAT3_2(Pre, Name, Post) Pre##Name##Post
  67
  68 /* Sometimes we need to store error codes in the `h_errno' variable.  */
  69 #ifdef NEED_H_ERRNO
  70 # define H_ERRNO_PARM , int *h_errnop
  71 # define H_ERRNO_VAR , &h_errno
  72 # define H_ERRNO_VAR_P &h_errno
  73 #else
  74 # define H_ERRNO_PARM
  75 # define H_ERRNO_VAR
  76 # define H_ERRNO_VAR_P NULL
  77 #endif
  78
  79 /* Some databases take the `stayopen' flag.  */
  80 #ifdef STAYOPEN
  81 # define STAYOPEN_TMP CONCAT2_1 (STAYOPEN, _tmp)
  82 # define STAYOPEN_TMPVAR &CONCAT2_1 (STAYOPEN_VAR, _tmp)
  83 #else
  84 # define STAYOPEN void
  85 # define STAYOPEN_VAR 0
  86 # define STAYOPEN_TMPVAR NULL
  87 #endif
  88
  89 #ifndef NEED__RES
  90 # define NEED__RES 0
  91 #endif
  92
  93 /* This handle for the NSS data base is shared between all
  94    set/get/endXXXent functions.  */
  95 static service_user *nip;
  96 /* Remember the last service used since the last call to  `endXXent'.  */
  97 static service_user *last_nip;
  98 /* Remember the first service_entry, it's always the same.  */
  99 static service_user *startp;
 100
 101 #ifdef STAYOPEN_TMP
 102 /* We need to remember the last `stayopen' flag given by the user
 103    since the `setent' function is only called for the first available
 104    service.  */
 105 static STAYOPEN_TMP;
 106 #endif
 107
 108 /* Protect above variable against multiple uses at the same time.  */
 109 __libc_lock_define_initialized (static, lock)
 110
 111 /* The lookup function for the first entry of this service.  */
 112 extern int DB_LOOKUP_FCT (service_user **nip, const char *name, void **fctp);
 113 \f
 114 void
 115 SETFUNC_NAME (STAYOPEN)
 116 {
 117   int save;
 118
 119   __libc_lock_lock (lock);
 120   __nss_setent (SETFUNC_NAME_STRING, DB_LOOKUP_FCT, &nip, &startp,
 121                 &last_nip, STAYOPEN_VAR, STAYOPEN_TMPVAR, NEED__RES);
 122
 123   save = errno;
 124   __libc_lock_unlock (lock);
 125   __set_errno (save);
 126 }
 127
 128
 129 void
 130 ENDFUNC_NAME (void)
 131 {
 132   int save;
 133
 134   __libc_lock_lock (lock);
 135   __nss_endent (ENDFUNC_NAME_STRING, DB_LOOKUP_FCT, &nip, &startp,
 136                 &last_nip, NEED__RES);
 137   save = errno;
 138   __libc_lock_unlock (lock);
 139   __set_errno (save);
 140 }
 141
 142
 143 int
 144 INTERNAL (REENTRANT_GETNAME) (LOOKUP_TYPE *resbuf, char *buffer, size_t buflen,
 145                               LOOKUP_TYPE **result H_ERRNO_PARM)
 146 {
 147   int status;
 148   int save;
 149
 150   __libc_lock_lock (lock);
 151   status = __nss_getent_r (GETFUNC_NAME_STRING, SETFUNC_NAME_STRING,
 152                            DB_LOOKUP_FCT, &nip, &startp, &last_nip,
 153                            STAYOPEN_TMPVAR, NEED__RES, resbuf, buffer,
 154                            buflen, (void **) result, H_ERRNO_VAR_P);
 155   save = errno;
 156   __libc_lock_unlock (lock);
 157   __set_errno (save);
 158   return status;
 159 }
 160
 161
 162 #include <shlib-compat.h>
 163 #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1_2)
 164 #define OLD(name) OLD1 (name)
 165 #define OLD1(name) __old_##name
 166
 167 int
 168 OLD (REENTRANT_GETNAME) (LOOKUP_TYPE *resbuf, char *buffer, size_t buflen,
 169                          LOOKUP_TYPE **result H_ERRNO_PARM)
 170 {
 171   int ret = INTERNAL (REENTRANT_GETNAME) (resbuf, buffer, buflen,
 172                                           result H_ERRNO_VAR);
 173
 174   if (ret != 0)
 175     ret = -1;
 176
 177   return ret;
 178 }
 179
 180 #define do_symbol_version(real, name, version) \
 181   compat_symbol (libc, real, name, version)
 182 do_symbol_version (OLD (REENTRANT_GETNAME), REENTRANT_GETNAME, GLIBC_2_0);
 183 #endif
 184
 185 #define do_default_symbol_version(real, name, version) \
 186   versioned_symbol (libc, real, name, version)
 187 do_default_symbol_version (INTERNAL (REENTRANT_GETNAME),
 188                            REENTRANT_GETNAME, GLIBC_2_1_2);