sysdeps/unix/sysv/linux/i386/lchown.c

   1 /* Copyright (C) 2000 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 <errno.h>
  20 #include <unistd.h>
  21
  22 #include <sysdep.h>
  23 #include <sys/syscall.h>
  24
  25 #include <linux/posix_types.h>
  26 #include "kernel-features.h"
  27
  28 #ifdef __NR_lchown
  29 extern int __syscall_lchown (const char *__file,
  30                              __kernel_uid_t __owner, __kernel_gid_t __group);
  31
  32 # ifdef __NR_lchown32
  33 extern int __syscall_lchown32 (const char *__file,
  34                                __kernel_uid32_t __owner, __kernel_gid32_t __group);
  35 #  if __ASSUME_32BITUIDS == 0
  36 /* This variable is shared with all files that need to check for 32bit
  37    uids.  */
  38 extern int __libc_missing_32bit_uids;
  39 #  endif
  40 # endif /* __NR_lchown32 */
  41
  42 int
  43 __lchown (const char *file, uid_t owner, gid_t group)
  44 {
  45 # if __ASSUME_32BITUIDS > 0
  46   return INLINE_SYSCALL (lchown32, 3, file, owner, group);
  47 # else
  48 #  ifdef __NR_lchown32
  49   if (__libc_missing_32bit_uids <= 0)
  50     {
  51       int result;
  52       int saved_errno = errno;
  53
  54       result = INLINE_SYSCALL (lchown32, 3, file, owner, group);
  55       if (result == 0 || errno != ENOSYS)
  56         return result;
  57
  58       __set_errno (saved_errno);
  59       __libc_missing_32bit_uids = 1;
  60     }
  61 #  endif /* __NR_lchown32 */
  62
  63   if (((owner + 1) > (uid_t) ((__kernel_uid_t) -1U))
  64       || ((group + 1) > (gid_t) ((__kernel_gid_t) -1U)))
  65     {
  66       __set_errno (EINVAL);
  67       return -1;
  68     }
  69
  70   return INLINE_SYSCALL (lchown, 3, file, owner, group);
  71 # endif
  72 }
  73
  74 weak_alias (__lchown, lchown)
  75
  76 #else
  77 # include <sysdeps/generic/lchown.c>
  78 #endif