login/getutent_r.c

   1 /* Copyright (C) 1996,1997,1998,2000,2001, 2002 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 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 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)