glibc/pwd/getpw.c

63 lines
1.8 KiB
C

/* Copyright (C) 1991-2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <alloca.h>
#include <errno.h>
#include <stdio.h>
#include <unistd.h>
#include <pwd.h>
/* Re-construct the password-file line for the given uid
in the given buffer. This knows the format that the caller
will expect, but this need not be the format of the password file. */
int __getpw (__uid_t uid, char *buf);
int
__getpw (__uid_t uid, char *buf)
{
size_t buflen;
char *tmpbuf;
struct passwd resbuf, *p;
if (buf == NULL)
{
__set_errno (EINVAL);
return -1;
}
buflen = __sysconf (_SC_GETPW_R_SIZE_MAX);
tmpbuf = alloca (buflen);
if (__getpwuid_r (uid, &resbuf, tmpbuf, buflen, &p) != 0)
return -1;
if (p == NULL)
return -1;
if (sprintf (buf, "%s:%s:%lu:%lu:%s:%s:%s", p->pw_name, p->pw_passwd,
(unsigned long int) p->pw_uid, (unsigned long int) p->pw_gid,
p->pw_gecos, p->pw_dir, p->pw_shell) < 0)
return -1;
return 0;
}
weak_alias (__getpw, getpw)
link_warning (getpw, "the `getpw' function is dangerous and should not be used.")