glibc/sysdeps/unix/sysv/linux/seteuid.c
2012-02-09 23:18:22 +00:00

61 lines
1.8 KiB
C

/* Copyright (C) 1998,1999,2002,2003,2004,2006 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 <errno.h>
#include <unistd.h>
#include <setxid.h>
#include <kernel-features.h>
#if defined __NR_setresuid || __ASSUME_SETRESUID_SYSCALL > 0
extern int __setresuid (uid_t ruid, uid_t euid, uid_t suid);
int
seteuid (uid_t uid)
{
int result;
if (uid == (uid_t) ~0)
{
__set_errno (EINVAL);
return -1;
}
# if __ASSUME_32BITUIDS > 0 && defined __NR_setresuid32
result = INLINE_SETXID_SYSCALL (setresuid32, 3, -1, uid, -1);
# else
/* First try the syscall. */
result = INLINE_SETXID_SYSCALL (setresuid, 3, -1, uid, -1);
# if __ASSUME_SETRESUID_SYSCALL == 0
if (result == -1 && errno == ENOSYS)
/* No system call available. Use emulation. This may not work
since `setreuid' also sets the saved user ID when UID is not
equal to the real user ID, making it impossible to switch back. */
result = __setreuid (-1, uid);
# endif
# endif
return result;
}
#ifndef seteuid
libc_hidden_def (seteuid)
#endif
#else
# include <sysdeps/unix/bsd/seteuid.c>
#endif