1: /* Copyright (C) 1996-1998,2000,2001,2002,2004 Free Software Foundation, Inc.
    2:    This file is part of the GNU C Library.
    3:    Contributed by Ulrich Drepper <drepper@cygnus.com>
    4:    and Paul Janzen <pcj@primenet.com>, 1996.
    5: 
    6:    The GNU C Library is free software; you can redistribute it and/or
    7:    modify it under the terms of the GNU Lesser General Public
    8:    License as published by the Free Software Foundation; either
    9:    version 2.1 of the License, or (at your option) any later version.
   10: 
   11:    The GNU C Library is distributed in the hope that it will be useful,
   12:    but WITHOUT ANY WARRANTY; without even the implied warranty of
   13:    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   14:    Lesser General Public License for more details.
   15: 
   16:    You should have received a copy of the GNU Lesser General Public
   17:    License along with the GNU C Library; if not, write to the Free
   18:    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   19:    02111-1307 USA.  */
   20: 
   21: #include <bits/libc-lock.h>
   22: #include <stdlib.h>
   23: #include <utmp.h>
   24: 
   25: #include "utmp-private.h"
   26: 
   27: 
   28: /* Functions defined here.  */
   29: static int setutent_unknown (void);
   30: static int getutent_r_unknown (struct utmp *buffer, struct utmp **result);
   31: static int getutid_r_unknown (const struct utmp *line, struct utmp *buffer,
   32:                               struct utmp **result);
   33: static int getutline_r_unknown (const struct utmp *id, struct utmp *buffer,
   34:                                 struct utmp **result);
   35: static struct utmp *pututline_unknown (const struct utmp *data);
   36: static void endutent_unknown (void);
   37: 
   38: /* Initial Jump table.  */
   39: const struct utfuncs __libc_utmp_unknown_functions =
   40: {
   41:   setutent_unknown,
   42:   getutent_r_unknown,
   43:   getutid_r_unknown,
   44:   getutline_r_unknown,
   45:   pututline_unknown,
   46:   endutent_unknown,
   47:   NULL
   48: };
   49: 
   50: /* Currently selected backend.  */
   51: const struct utfuncs *__libc_utmp_jump_table = &__libc_utmp_unknown_functions;
   52: 
   53: /* We need to protect the opening of the file.  */
   54: __libc_lock_define_initialized (, __libc_utmp_lock attribute_hidden)
   55: 
   56: 
   57: static int
   58: setutent_unknown (void)
   59: {
   60:   int result;
   61: 
   62:   result = (*__libc_utmp_file_functions.setutent) ();
   63:   if (result)
   64:     __libc_utmp_jump_table = &__libc_utmp_file_functions;
   65: 
   66:   return result;
   67: }
   68: 
   69: 
   70: static int
   71: getutent_r_unknown (struct utmp *buffer, struct utmp **result)
   72: {
   73:   /* The backend was not yet initialized.  */
   74:   if (setutent_unknown ())
   75:     return (*__libc_utmp_jump_table->getutent_r) (buffer, result);
   76: 
   77:   /* Not available.  */
   78:   *result = NULL;
   79:   return -1;
   80: }
   81: 
   82: 
   83: static int
   84: getutid_r_unknown (const struct utmp *id, struct utmp *buffer,
   85:                    struct utmp **result)
   86: {
   87:   /* The backend was not yet initialized.  */
   88:   if (setutent_unknown ())
   89:     return (*__libc_utmp_jump_table->getutid_r) (id, buffer, result);
   90: 
   91:   /* Not available.  */
   92:   *result = NULL;
   93:   return -1;
   94: }
   95: 
   96: 
   97: static int
   98: getutline_r_unknown (const struct utmp *line, struct utmp *buffer,
   99:                      struct utmp **result)
  100: {
  101:   /* The backend was not yet initialized.  */
  102:   if (setutent_unknown ())
  103:     return (*__libc_utmp_jump_table->getutline_r) (line, buffer, result);
  104: 
  105:   /* Not available.  */
  106:   *result = NULL;
  107:   return -1;
  108: }
  109: 
  110: 
  111: static struct utmp *
  112: pututline_unknown (const struct utmp *data)
  113: {
  114:   /* The backend was not yet initialized.  */
  115:   if (setutent_unknown ())
  116:     return (*__libc_utmp_jump_table->pututline) (data);
  117: 
  118:   /* Not available.  */
  119:   return NULL;
  120: }
  121: 
  122: 
  123: static void
  124: endutent_unknown (void)
  125: {
  126:   /* Nothing to do.  */
  127: }
  128: 
  129: 
  130: void
  131: __setutent (void)
  132: {
  133:   __libc_lock_lock (__libc_utmp_lock);
  134: 
  135:   (*__libc_utmp_jump_table->setutent) ();
  136: 
  137:   __libc_lock_unlock (__libc_utmp_lock);
  138: }
  139: weak_alias (__setutent, setutent)
  140: 
  141: 
  142: int
  143: __getutent_r (struct utmp *buffer, struct utmp **result)
  144: {
  145:   int retval;
  146: 
  147:   __libc_lock_lock (__libc_utmp_lock);
  148: 
  149:   retval = (*__libc_utmp_jump_table->getutent_r) (buffer, result);
  150: 
  151:   __libc_lock_unlock (__libc_utmp_lock);
  152: 
  153:   return retval;
  154: }
  155: weak_alias (__getutent_r, getutent_r)
  156: 
  157: 
  158: struct utmp *
  159: __pututline (const struct utmp *data)
  160: {
  161:   struct utmp *buffer;
  162: 
  163:   __libc_lock_lock (__libc_utmp_lock);
  164: 
  165:   buffer = (*__libc_utmp_jump_table->pututline) (data);
  166: 
  167:   __libc_lock_unlock (__libc_utmp_lock);
  168: 
  169:   return buffer;
  170: }
  171: weak_alias (__pututline, pututline)
  172: 
  173: 
  174: void
  175: __endutent (void)
  176: {
  177:   __libc_lock_lock (__libc_utmp_lock);
  178: 
  179:   (*__libc_utmp_jump_table->endutent) ();
  180:   __libc_utmp_jump_table = &__libc_utmp_unknown_functions;
  181: 
  182:   __libc_lock_unlock (__libc_utmp_lock);
  183: }
  184: weak_alias (__endutent, endutent)