1: /* Copyright (C) 1996,97,98,99,2000,2002,2004 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: #define NEW(name) NEW1 (name)
   57: #define NEW1(name) __new_##name
   58: 
   59: #define SETFUNC_NAME_STRING STRINGIZE (SETFUNC_NAME)
   60: #define GETFUNC_NAME_STRING STRINGIZE (REENTRANT_GETNAME)
   61: #define ENDFUNC_NAME_STRING STRINGIZE (ENDFUNC_NAME)
   62: #define DATABASE_NAME_STRING STRINGIZE (DATABASE_NAME)
   63: #define STRINGIZE(Name) STRINGIZE1 (Name)
   64: #define STRINGIZE1(Name) #Name
   65: 
   66: #ifndef DB_LOOKUP_FCT
   67: # define DB_LOOKUP_FCT CONCAT3_1 (__nss_, DATABASE_NAME, _lookup)
   68: # define CONCAT3_1(Pre, Name, Post) CONCAT3_2 (Pre, Name, Post)
   69: # define CONCAT3_2(Pre, Name, Post) Pre##Name##Post
   70: #endif
   71: 
   72: /* Sometimes we need to store error codes in the `h_errno' variable.  */
   73: #ifdef NEED_H_ERRNO
   74: # define H_ERRNO_PARM , int *h_errnop
   75: # define H_ERRNO_VAR , &h_errno
   76: # define H_ERRNO_VAR_P &h_errno
   77: #else
   78: # define H_ERRNO_PARM
   79: # define H_ERRNO_VAR
   80: # define H_ERRNO_VAR_P NULL
   81: #endif
   82: 
   83: /* Some databases take the `stayopen' flag.  */
   84: #ifdef STAYOPEN
   85: # define STAYOPEN_TMP CONCAT2_1 (STAYOPEN, _tmp)
   86: # define STAYOPEN_TMPVAR &CONCAT2_1 (STAYOPEN_VAR, _tmp)
   87: #else
   88: # define STAYOPEN void
   89: # define STAYOPEN_VAR 0
   90: # define STAYOPEN_TMPVAR NULL
   91: #endif
   92: 
   93: #ifndef NEED__RES
   94: # define NEED__RES 0
   95: #endif
   96: 
   97: /* This handle for the NSS data base is shared between all
   98:    set/get/endXXXent functions.  */
   99: static service_user *nip;
  100: /* Remember the last service used since the last call to  `endXXent'.  */
  101: static service_user *last_nip;
  102: /* Remember the first service_entry, it's always the same.  */
  103: static service_user *startp;
  104: 
  105: #ifdef STAYOPEN_TMP
  106: /* We need to remember the last `stayopen' flag given by the user
  107:    since the `setent' function is only called for the first available
  108:    service.  */
  109: static STAYOPEN_TMP;
  110: #endif
  111: 
  112: /* Protect above variable against multiple uses at the same time.  */
  113: __libc_lock_define_initialized (static, lock)
  114: 
  115: /* The lookup function for the first entry of this service.  */
  116: extern int DB_LOOKUP_FCT (service_user **nip, const char *name, void **fctp)
  117:      internal_function;
  118: libc_hidden_proto (DB_LOOKUP_FCT)
  119: ^L
  120: void
  121: SETFUNC_NAME (STAYOPEN)
  122: {
  123:   int save;
  124: 
  125:   __libc_lock_lock (lock);
  126:   __nss_setent (SETFUNC_NAME_STRING, DB_LOOKUP_FCT, &nip, &startp,
  127:                 &last_nip, STAYOPEN_VAR, STAYOPEN_TMPVAR, NEED__RES);
  128: 
  129:   save = errno;
  130:   __libc_lock_unlock (lock);
  131:   __set_errno (save);
  132: }
  133: 
  134: 
  135: void
  136: ENDFUNC_NAME (void)
  137: {
  138:   int save;
  139: 
  140:   /* If the service has not been used before do not do anything.  */
  141:   if (startp != NULL)
  142:     {
  143:       __libc_lock_lock (lock);
  144:       __nss_endent (ENDFUNC_NAME_STRING, DB_LOOKUP_FCT, &nip, &startp,
  145:                     &last_nip, NEED__RES);
  146:       save = errno;
  147:       __libc_lock_unlock (lock);
  148:       __set_errno (save);
  149:     }
  150: }
  151: 
  152: 
  153: int
  154: INTERNAL (REENTRANT_GETNAME) (LOOKUP_TYPE *resbuf, char *buffer, size_t buflen,
  155:                               LOOKUP_TYPE **result H_ERRNO_PARM)
  156: {
  157:   int status;
  158:   int save;
  159: 
  160:   __libc_lock_lock (lock);
  161:   status = __nss_getent_r (GETFUNC_NAME_STRING, SETFUNC_NAME_STRING,
  162:                            DB_LOOKUP_FCT, &nip, &startp, &last_nip,
  163:                            STAYOPEN_TMPVAR, NEED__RES, resbuf, buffer,
  164:                            buflen, (void **) result, H_ERRNO_VAR_P);
  165:   save = errno;
  166:   __libc_lock_unlock (lock);
  167:   __set_errno (save);
  168:   return status;
  169: }
  170: 
  171: 
  172: #include <shlib-compat.h>
  173: #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1_2)
  174: #define OLD(name) OLD1 (name)
  175: #define OLD1(name) __old_##name
  176: 
  177: int
  178: attribute_compat_text_section
  179: OLD (REENTRANT_GETNAME) (LOOKUP_TYPE *resbuf, char *buffer, size_t buflen,
  180:                          LOOKUP_TYPE **result H_ERRNO_PARM)
  181: {
  182:   int ret = INTERNAL (REENTRANT_GETNAME) (resbuf, buffer, buflen,
  183:                                           result H_ERRNO_VAR);
  184: 
  185:   if (ret != 0)
  186:     ret = -1;
  187: 
  188:   return ret;
  189: }
  190: 
  191: #define do_symbol_version(real, name, version) \
  192:   compat_symbol (libc, real, name, version)
  193: do_symbol_version (OLD (REENTRANT_GETNAME), REENTRANT_GETNAME, GLIBC_2_0);
  194: #endif
  195: 
  196: /* As INTERNAL (REENTRANT_GETNAME) may be hidden, we need an alias
  197:    in between so that the REENTRANT_GETNAME@@GLIBC_2.1.2 is not
  198:    hidden too.  */
  199: strong_alias (INTERNAL (REENTRANT_GETNAME), NEW (REENTRANT_GETNAME));
  200: 
  201: #define do_default_symbol_version(real, name, version) \
  202:   versioned_symbol (libc, real, name, version)
  203: do_default_symbol_version (NEW (REENTRANT_GETNAME),
  204:                            REENTRANT_GETNAME, GLIBC_2_1_2);
  205: 
  206: static_link_warning (SETFUNC_NAME)
  207: static_link_warning (ENDFUNC_NAME)
  208: static_link_warning (REENTRANT_GETNAME)