sysdeps/mach/hurd/getlogin_r.c

   1 /* Reentrant function to return the current login name.  Hurd version.
   2    Copyright (C) 1996-2018 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   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, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <unistd.h>
  21 #include <hurd.h>
  22 #include <string.h>
  23
  24 /* Return at most NAME_LEN characters of the login name of the user in NAME.
  25    If it cannot be determined or some other error occurred, return the error
  26    code.  Otherwise return 0.  */
  27 int
  28 __getlogin_r (char *name, size_t name_len)
  29 {
  30   string_t login;
  31   error_t err;
  32
  33   if (err = __USEPORT (PROC, __proc_getlogin (port, login)))
  34     return errno = err;
  35
  36   size_t len = __strnlen (login, sizeof login - 1) + 1;
  37   if (len > name_len)
  38     {
  39       errno = ERANGE;
  40       return errno;
  41     }
  42
  43   memcpy (name, login, len);
  44   return 0;
  45 }
  46 libc_hidden_def (__getlogin_r)
  47 weak_alias (__getlogin_r, getlogin_r)
  48 libc_hidden_weak (getlogin_r)