grp/grp.h

   1 /* Copyright (C) 1991-2014 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 /*
  19  *      POSIX Standard: 9.2.1 Group Database Access     <grp.h>
  20  */
  21
  22 #ifndef _GRP_H
  23 #define _GRP_H  1
  24
  25 #include <features.h>
  26
  27 __BEGIN_DECLS
  28
  29 #include <bits/types.h>
  30
  31 #define __need_size_t
  32 #include <stddef.h>
  33
  34
  35 /* For the Single Unix specification we must define this type here.  */
  36 #if (defined __USE_XOPEN || defined __USE_XOPEN2K) && !defined __gid_t_defined
  37 typedef __gid_t gid_t;
  38 # define __gid_t_defined
  39 #endif
  40
  41 /* The group structure.  */
  42 struct group
  43   {
  44     char *gr_name;              /* Group name.  */
  45     char *gr_passwd;            /* Password.    */
  46     __gid_t gr_gid;             /* Group ID.    */
  47     char **gr_mem;              /* Member list. */
  48   };
  49
  50
  51 #ifdef __USE_MISC
  52 # define __need_FILE
  53 # include <stdio.h>
  54 #endif
  55
  56
  57 #if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
  58 /* Rewind the group-file stream.
  59
  60    This function is a possible cancellation point and therefore not
  61    marked with __THROW.  */
  62 extern void setgrent (void);
  63 #endif
  64
  65 #if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
  66 /* Close the group-file stream.
  67
  68    This function is a possible cancellation point and therefore not
  69    marked with __THROW.  */
  70 extern void endgrent (void);
  71
  72 /* Read an entry from the group-file stream, opening it if necessary.
  73
  74    This function is a possible cancellation point and therefore not
  75    marked with __THROW.  */
  76 extern struct group *getgrent (void);
  77 #endif
  78
  79 #ifdef  __USE_MISC
  80 /* Read a group entry from STREAM.
  81
  82    This function is not part of POSIX and therefore no official
  83    cancellation point.  But due to similarity with an POSIX interface
  84    or due to the implementation it is a cancellation point and
  85    therefore not marked with __THROW.  */
  86 extern struct group *fgetgrent (FILE *__stream);
  87 #endif
  88
  89 #ifdef __USE_GNU
  90 /* Write the given entry onto the given stream.
  91
  92    This function is not part of POSIX and therefore no official
  93    cancellation point.  But due to similarity with an POSIX interface
  94    or due to the implementation it is a cancellation point and
  95    therefore not marked with __THROW.  */
  96 extern int putgrent (const struct group *__restrict __p,
  97                      FILE *__restrict __f);
  98 #endif
  99
 100 /* Search for an entry with a matching group ID.
 101
 102    This function is a possible cancellation point and therefore not
 103    marked with __THROW.  */
 104 extern struct group *getgrgid (__gid_t __gid);
 105
 106 /* Search for an entry with a matching group name.
 107
 108    This function is a possible cancellation point and therefore not
 109    marked with __THROW.  */
 110 extern struct group *getgrnam (const char *__name);
 111
 112 #ifdef __USE_POSIX
 113
 114 # ifdef __USE_MISC
 115 /* Reasonable value for the buffer sized used in the reentrant
 116    functions below.  But better use `sysconf'.  */
 117 #  define NSS_BUFLEN_GROUP      1024
 118 # endif
 119
 120 /* Reentrant versions of some of the functions above.
 121
 122    PLEASE NOTE: the `getgrent_r' function is not (yet) standardized.
 123    The interface may change in later versions of this library.  But
 124    the interface is designed following the principals used for the
 125    other reentrant functions so the chances are good this is what the
 126    POSIX people would choose.
 127
 128    This function is not part of POSIX and therefore no official
 129    cancellation point.  But due to similarity with an POSIX interface
 130    or due to the implementation it is a cancellation point and
 131    therefore not marked with __THROW.  */
 132
 133 # ifdef __USE_GNU
 134 extern int getgrent_r (struct group *__restrict __resultbuf,
 135                        char *__restrict __buffer, size_t __buflen,
 136                        struct group **__restrict __result);
 137 # endif
 138
 139 /* Search for an entry with a matching group ID.
 140
 141    This function is a possible cancellation point and therefore not
 142    marked with __THROW.  */
 143 extern int getgrgid_r (__gid_t __gid, struct group *__restrict __resultbuf,
 144                        char *__restrict __buffer, size_t __buflen,
 145                        struct group **__restrict __result);
 146
 147 /* Search for an entry with a matching group name.
 148
 149    This function is a possible cancellation point and therefore not
 150    marked with __THROW.  */
 151 extern int getgrnam_r (const char *__restrict __name,
 152                        struct group *__restrict __resultbuf,
 153                        char *__restrict __buffer, size_t __buflen,
 154                        struct group **__restrict __result);
 155
 156 # ifdef __USE_MISC
 157 /* Read a group entry from STREAM.  This function is not standardized
 158    an probably never will.
 159
 160    This function is not part of POSIX and therefore no official
 161    cancellation point.  But due to similarity with an POSIX interface
 162    or due to the implementation it is a cancellation point and
 163    therefore not marked with __THROW.  */
 164 extern int fgetgrent_r (FILE *__restrict __stream,
 165                         struct group *__restrict __resultbuf,
 166                         char *__restrict __buffer, size_t __buflen,
 167                         struct group **__restrict __result);
 168 # endif
 169
 170 #endif  /* POSIX or reentrant */
 171
 172
 173 #ifdef  __USE_MISC
 174
 175 # define __need_size_t
 176 # include <stddef.h>
 177
 178 /* Set the group set for the current user to GROUPS (N of them).  */
 179 extern int setgroups (size_t __n, const __gid_t *__groups) __THROW;
 180
 181 /* Store at most *NGROUPS members of the group set for USER into
 182    *GROUPS.  Also include GROUP.  The actual number of groups found is
 183    returned in *NGROUPS.  Return -1 if the if *NGROUPS is too small.
 184
 185    This function is not part of POSIX and therefore no official
 186    cancellation point.  But due to similarity with an POSIX interface
 187    or due to the implementation it is a cancellation point and
 188    therefore not marked with __THROW.  */
 189 extern int getgrouplist (const char *__user, __gid_t __group,
 190                          __gid_t *__groups, int *__ngroups);
 191
 192 /* Initialize the group set for the current user
 193    by reading the group database and using all groups
 194    of which USER is a member.  Also include GROUP.
 195
 196    This function is not part of POSIX and therefore no official
 197    cancellation point.  But due to similarity with an POSIX interface
 198    or due to the implementation it is a cancellation point and
 199    therefore not marked with __THROW.  */
 200 extern int initgroups (const char *__user, __gid_t __group);
 201
 202 #endif /* Use misc.  */
 203
 204 __END_DECLS
 205
 206 #endif /* grp.h  */