lib/openat.h

   1 /* provide a replacement openat function
   2    Copyright (C) 2004-2006, 2008-2025 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 <https://www.gnu.org/licenses/>.  */
  16
  17 /* written by Jim Meyering */
  18
  19 #ifndef _GL_HEADER_OPENAT
  20 #define _GL_HEADER_OPENAT
  21
  22 /* This file uses _GL_INLINE_HEADER_BEGIN, _GL_INLINE, _Noreturn,
  23    _GL_ATTRIBUTE_DEPRECATED, HAVE_OPENAT.  */
  24 #if !_GL_CONFIG_H_INCLUDED
  25  #error "Please include config.h first."
  26 #endif
  27
  28 #include <fcntl.h>
  29
  30 #include <sys/types.h>
  31 #include <sys/stat.h>
  32 #include <unistd.h>
  33
  34 _GL_INLINE_HEADER_BEGIN
  35
  36 #ifdef __cplusplus
  37 extern "C" {
  38 #endif
  39
  40
  41 #if !HAVE_OPENAT
  42
  43 int openat_permissive (int fd, char const *file, int flags, mode_t mode,
  44                        int *cwd_errno);
  45 bool openat_needs_fchdir (void);
  46
  47 #else
  48
  49 # define openat_permissive(Fd, File, Flags, Mode, Cwd_errno) \
  50     openat (Fd, File, Flags, Mode)
  51 # define openat_needs_fchdir() false
  52
  53 #endif
  54
  55 _Noreturn void openat_restore_fail (int);
  56 _Noreturn void openat_save_fail (int);
  57
  58 /* Using these function names makes application code
  59    slightly more readable than it would be with
  60    fchownat (..., 0) or fchownat (..., AT_SYMLINK_NOFOLLOW).  */
  61
  62 #if GNULIB_CHOWNAT
  63
  64 # ifndef CHOWNAT_INLINE
  65 #  define CHOWNAT_INLINE _GL_INLINE
  66 # endif
  67
  68 CHOWNAT_INLINE int
  69 chownat (int fd, char const *file, uid_t owner, gid_t group)
  70 {
  71   return fchownat (fd, file, owner, group, 0);
  72 }
  73
  74 CHOWNAT_INLINE int
  75 lchownat (int fd, char const *file, uid_t owner, gid_t group)
  76 {
  77   return fchownat (fd, file, owner, group, AT_SYMLINK_NOFOLLOW);
  78 }
  79
  80 #endif
  81
  82 #if GNULIB_CHMODAT
  83
  84 # ifndef CHMODAT_INLINE
  85 #  define CHMODAT_INLINE _GL_INLINE
  86 # endif
  87
  88 CHMODAT_INLINE int
  89 chmodat (int fd, char const *file, mode_t mode)
  90 {
  91   return fchmodat (fd, file, mode, 0);
  92 }
  93
  94 CHMODAT_INLINE int
  95 lchmodat (int fd, char const *file, mode_t mode)
  96 {
  97   return fchmodat (fd, file, mode, AT_SYMLINK_NOFOLLOW);
  98 }
  99
 100 #endif
 101
 102 #if GNULIB_STATAT
 103
 104 # ifndef STATAT_INLINE
 105 #  define STATAT_INLINE _GL_INLINE
 106 # endif
 107
 108 _GL_ATTRIBUTE_DEPRECATED
 109 STATAT_INLINE int
 110 statat (int fd, char const *name, struct stat *st)
 111 {
 112   return fstatat (fd, name, st, 0);
 113 }
 114
 115 _GL_ATTRIBUTE_DEPRECATED
 116 STATAT_INLINE int
 117 lstatat (int fd, char const *name, struct stat *st)
 118 {
 119   return fstatat (fd, name, st, AT_SYMLINK_NOFOLLOW);
 120 }
 121
 122 #endif
 123
 124 /* For now, there are no wrappers named laccessat or leuidaccessat,
 125    since gnulib doesn't support faccessat(,AT_SYMLINK_NOFOLLOW) and
 126    since access rights on symlinks are of limited utility.  Likewise,
 127    wrappers are not provided for accessat or euidaccessat, so as to
 128    avoid dragging in -lgen on some platforms.  */
 129
 130
 131 #ifdef __cplusplus
 132 }
 133 #endif
 134
 135 _GL_INLINE_HEADER_END
 136
 137 #endif /* _GL_HEADER_OPENAT */