sysdeps/unix/sysv/linux/openat.c

   1 /* Copyright (C) 2005-2015 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 <string.h>
  24 #include <sys/stat.h>
  25 #include <sysdep-cancel.h>
  26 #include <not-cancel.h>
  27
  28
  29 #ifndef OPENAT
  30 # define OPENAT openat
  31 #endif
  32
  33
  34 #define OPENAT_NOT_CANCEL CONCAT (OPENAT)
  35 #define CONCAT(name) CONCAT2 (name)
  36 #define CONCAT2(name) __##name##_nocancel
  37
  38
  39 int
  40 OPENAT_NOT_CANCEL (int fd, const char *file, int oflag, mode_t mode)
  41 {
  42
  43   /* We have to add the O_LARGEFILE flag for openat64.  */
  44 #ifdef MORE_OFLAGS
  45   oflag |= MORE_OFLAGS;
  46 #endif
  47
  48   return INLINE_SYSCALL (openat, 4, fd, file, oflag, mode);
  49 }
  50
  51 #define UNDERIZE(name) UNDERIZE_1 (name)
  52 #define UNDERIZE_1(name) __##name
  53 #define __OPENAT UNDERIZE (OPENAT)
  54
  55
  56 /* Open FILE with access OFLAG.  Interpret relative paths relative to
  57    the directory associated with FD.  If OFLAG includes O_CREAT or
  58    O_TMPFILE, a fourth argument is the file protection.  */
  59 int
  60 __OPENAT (int fd, const char *file, int oflag, ...)
  61 {
  62   mode_t mode = 0;
  63   if (__OPEN_NEEDS_MODE (oflag))
  64     {
  65       va_list arg;
  66       va_start (arg, oflag);
  67       mode = va_arg (arg, mode_t);
  68       va_end (arg);
  69     }
  70
  71   return SYSCALL_CANCEL (openat, fd, file, oflag, mode);
  72 }
  73 libc_hidden_def (__OPENAT)
  74 weak_alias (__OPENAT, OPENAT)