hurd/lookup-at.c

   1 /* Lookup helper function for Hurd implementation of *at functions.
   2    Copyright (C) 2006-2017 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <hurd.h>
  20 #include <hurd/lookup.h>
  21 #include <hurd/fd.h>
  22 #include <string.h>
  23 #include <fcntl.h>
  24
  25 file_t
  26 __file_name_lookup_at (int fd, int at_flags,
  27                        const char *file_name, int flags, mode_t mode)
  28 {
  29   error_t err;
  30   file_t result;
  31
  32   if ((at_flags & AT_SYMLINK_FOLLOW) && (at_flags & AT_SYMLINK_NOFOLLOW))
  33     return (__hurd_fail (EINVAL), MACH_PORT_NULL);
  34
  35   flags |= (at_flags & AT_SYMLINK_NOFOLLOW) ? O_NOLINK : 0;
  36   at_flags &= ~AT_SYMLINK_NOFOLLOW;
  37   if (at_flags & AT_SYMLINK_FOLLOW)
  38     flags &= ~O_NOLINK;
  39   at_flags &= ~AT_SYMLINK_FOLLOW;
  40   if (at_flags != 0)
  41     return (__hurd_fail (EINVAL), MACH_PORT_NULL);
  42
  43   if (fd == AT_FDCWD || file_name[0] == '/')
  44     return __file_name_lookup (file_name, flags, mode);
  45
  46   file_t startdir;
  47   error_t use_init_port (int which, error_t (*operate) (mach_port_t))
  48     {
  49       return (which == INIT_PORT_CWDIR ? (*operate) (startdir) :
  50               _hurd_ports_use (which, operate));
  51     }
  52
  53   err = HURD_DPORT_USE (fd, (startdir = port,
  54                              __hurd_file_name_lookup (&use_init_port,
  55                                                       &__getdport, NULL,
  56                                                       file_name,
  57                                                       flags,
  58                                                       mode & ~_hurd_umask,
  59                                                       &result)));
  60
  61   return err ? (__hurd_dfail (fd, err), MACH_PORT_NULL) : result;
  62 }
  63
  64 file_t
  65 __file_name_split_at (int fd, const char *file_name, char **name)
  66 {
  67   error_t err;
  68   file_t result;
  69
  70   if (fd == AT_FDCWD || file_name[0] == '/')
  71     return __file_name_split (file_name, name);
  72
  73   err = __hurd_file_name_split (&_hurd_ports_use, &__getdport, 0,
  74                                 file_name, &result, name);
  75
  76   file_t startdir;
  77   error_t use_init_port (int which, error_t (*operate) (mach_port_t))
  78   {
  79     return (which == INIT_PORT_CWDIR ? (*operate) (startdir) :
  80             _hurd_ports_use (which, operate));
  81   }
  82
  83   err = HURD_DPORT_USE (fd, (startdir = port,
  84                              __hurd_file_name_split (&use_init_port,
  85                                                      &__getdport, 0,
  86                                                      file_name,
  87                                                      &result, name)));
  88
  89   return err ? (__hurd_dfail (fd, err), MACH_PORT_NULL) : result;
  90 }
  91
  92 file_t
  93 __directory_name_split_at (int fd, const char *directory_name, char **name)
  94 {
  95   error_t err;
  96   file_t result;
  97
  98   if (fd == AT_FDCWD || directory_name[0] == '/')
  99     return __directory_name_split (directory_name, name);
 100
 101   file_t startdir;
 102   error_t use_init_port (int which, error_t (*operate) (mach_port_t))
 103     {
 104       return (which == INIT_PORT_CWDIR ? (*operate) (startdir) :
 105               _hurd_ports_use (which, operate));
 106     }
 107
 108   err = HURD_DPORT_USE (fd, (startdir = port,
 109                              __hurd_directory_name_split (&use_init_port,
 110                                                           &__getdport, 0,
 111                                                           directory_name,
 112                                                           &result, name)));
 113
 114   return err ? (__hurd_dfail (fd, err), MACH_PORT_NULL) : result;
 115 }