io/openat.c

   1 /* Copyright (C) 2005, 2006, 2007 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 Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the 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    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <errno.h>
  19 #include <fcntl.h>
  20 #include <stdarg.h>
  21 #include <stddef.h>
  22 #include <stdio.h>
  23 #include <sys/stat.h>
  24
  25 /* Open FILE with access OFLAG.  Interpret relative paths relative to
  26    the directory associated with FD.  If OFLAG includes O_CREAT, a
  27    third argument is the file protection.  */
  28 int
  29 __openat (fd, file, oflag)
  30      int fd;
  31      const char *file;
  32      int oflag;
  33 {
  34   int mode;
  35
  36   if (file == NULL)
  37     {
  38       __set_errno (EINVAL);
  39       return -1;
  40     }
  41
  42   if (fd != AT_FDCWD && file[0] != '/')
  43     {
  44       /* Check FD is associated with a directory.  */
  45       struct stat64 st;
  46       if (__fxstat64 (_STAT_VER, fd, &st) != 0)
  47         return -1;
  48
  49       if (!S_ISDIR (st.st_mode))
  50         {
  51           __set_errno (ENOTDIR);
  52           return -1;
  53         }
  54     }
  55
  56   if (oflag & O_CREAT)
  57     {
  58       va_list arg;
  59       va_start (arg, oflag);
  60       mode = va_arg (arg, int);
  61       va_end (arg);
  62     }
  63
  64   __set_errno (ENOSYS);
  65   return -1;
  66 }
  67 libc_hidden_def (__openat)
  68 weak_alias (__openat, openat)
  69 stub_warning (openat)
  70
  71
  72 int
  73 __openat_2 (fd, file, oflag)
  74      int fd;
  75      const char *file;
  76      int oflag;
  77 {
  78   if (oflag & O_CREAT)
  79     __fortify_fail ("invalid openat call: O_CREAT without mode");
  80
  81   return __openat (fd, file, oflag);
  82 }
  83 stub_warning (__openat_2)
  84
  85 #include <stub-tag.h>