pwd/getpw.c

   1 /* Copyright (C) 1991, 1992, 1996, 1998, 1999 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 Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    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    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #include <alloca.h>
  20 #include <errno.h>
  21 #include <stdio.h>
  22 #include <unistd.h>
  23 #include <pwd.h>
  24
  25
  26 /* Re-construct the password-file line for the given uid
  27    in the given buffer.  This knows the format that the caller
  28    will expect, but this need not be the format of the password file.  */
  29
  30 int __getpw __P ((__uid_t uid, char *buf));
  31
  32 int
  33 __getpw (uid, buf)
  34      __uid_t uid;
  35      char *buf;
  36 {
  37   size_t buflen;
  38   char *tmpbuf;
  39   struct passwd resbuf, *p;
  40
  41   if (buf == NULL)
  42     {
  43       __set_errno (EINVAL);
  44       return -1;
  45     }
  46
  47   buflen = __sysconf (_SC_GETPW_R_SIZE_MAX);
  48   tmpbuf = alloca (buflen);
  49
  50   if (__getpwuid_r (uid, &resbuf, tmpbuf, buflen, &p) != 0)
  51     return -1;
  52
  53   if (p == NULL)
  54     return -1;
  55
  56   if (sprintf (buf, "%s:%s:%lu:%lu:%s:%s:%s", p->pw_name, p->pw_passwd,
  57                (unsigned long int) p->pw_uid, (unsigned long int) p->pw_gid,
  58                p->pw_gecos, p->pw_dir, p->pw_shell) < 0)
  59     return -1;
  60
  61   return 0;
  62 }
  63 weak_alias (__getpw, getpw)
  64
  65 link_warning (getpw, "the `getpw' function is dangerous and should not be used.")