lib/openat.h

   1 /* provide a replacement openat function
   2    Copyright (C) 2004-2006, 2008-2017 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program 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
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  16
  17 /* written by Jim Meyering */
  18
  19 #ifndef _GL_HEADER_OPENAT
  20 #define _GL_HEADER_OPENAT
  21
  22 #include <fcntl.h>
  23
  24 #include <sys/types.h>
  25 #include <sys/stat.h>
  26 #include <unistd.h>
  27 #include <stdbool.h>
  28
  29 #ifndef _GL_INLINE_HEADER_BEGIN
  30  #error "Please include config.h first."
  31 #endif
  32 _GL_INLINE_HEADER_BEGIN
  33
  34 #if !HAVE_OPENAT
  35
  36 int openat_permissive (int fd, char const *file, int flags, mode_t mode,
  37                        int *cwd_errno);
  38 bool openat_needs_fchdir (void);
  39
  40 #else
  41
  42 # define openat_permissive(Fd, File, Flags, Mode, Cwd_errno) \
  43     openat (Fd, File, Flags, Mode)
  44 # define openat_needs_fchdir() false
  45
  46 #endif
  47
  48 _Noreturn void openat_restore_fail (int);
  49 _Noreturn void openat_save_fail (int);
  50
  51 /* Using these function names makes application code
  52    slightly more readable than it would be with
  53    fchownat (..., 0) or fchownat (..., AT_SYMLINK_NOFOLLOW).  */
  54
  55 #if GNULIB_FCHOWNAT
  56
  57 # ifndef FCHOWNAT_INLINE
  58 #  define FCHOWNAT_INLINE _GL_INLINE
  59 # endif
  60
  61 FCHOWNAT_INLINE int
  62 chownat (int fd, char const *file, uid_t owner, gid_t group)
  63 {
  64   return fchownat (fd, file, owner, group, 0);
  65 }
  66
  67 FCHOWNAT_INLINE int
  68 lchownat (int fd, char const *file, uid_t owner, gid_t group)
  69 {
  70   return fchownat (fd, file, owner, group, AT_SYMLINK_NOFOLLOW);
  71 }
  72
  73 #endif
  74
  75 #if GNULIB_FCHMODAT
  76
  77 # ifndef FCHMODAT_INLINE
  78 #  define FCHMODAT_INLINE _GL_INLINE
  79 # endif
  80
  81 FCHMODAT_INLINE int
  82 chmodat (int fd, char const *file, mode_t mode)
  83 {
  84   return fchmodat (fd, file, mode, 0);
  85 }
  86
  87 FCHMODAT_INLINE int
  88 lchmodat (int fd, char const *file, mode_t mode)
  89 {
  90   return fchmodat (fd, file, mode, AT_SYMLINK_NOFOLLOW);
  91 }
  92
  93 #endif
  94
  95 #if GNULIB_STATAT
  96
  97 # ifndef STATAT_INLINE
  98 #  define STATAT_INLINE _GL_INLINE
  99 # endif
 100
 101 STATAT_INLINE int
 102 statat (int fd, char const *name, struct stat *st)
 103 {
 104   return fstatat (fd, name, st, 0);
 105 }
 106
 107 STATAT_INLINE int
 108 lstatat (int fd, char const *name, struct stat *st)
 109 {
 110   return fstatat (fd, name, st, AT_SYMLINK_NOFOLLOW);
 111 }
 112
 113 #endif
 114
 115 /* For now, there are no wrappers named laccessat or leuidaccessat,
 116    since gnulib doesn't support faccessat(,AT_SYMLINK_NOFOLLOW) and
 117    since access rights on symlinks are of limited utility.  Likewise,
 118    wrappers are not provided for accessat or euidaccessat, so as to
 119    avoid dragging in -lgen on some platforms.  */
 120
 121 _GL_INLINE_HEADER_END
 122
 123 #endif /* _GL_HEADER_OPENAT */