| /* Copyright (C) 1993-2014 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <errno.h> |
| #include <stddef.h> |
| #include <dirent.h> |
| #include <unistd.h> |
| #include <endian.h> |
| #include <assert.h> |
| |
| /* Read a directory entry from DIRP. */ |
| struct dirent * |
| __readdir (DIR *dirp) |
| { |
| struct dirent64 *entry64 = __readdir64 (dirp); |
| |
| if (sizeof (struct dirent64) == sizeof (struct dirent)) |
| /* We should in fact just be an alias to readdir64 on this machine. */ |
| return (struct dirent *) entry64; |
| |
| /* These are all compile-time constants. We know that d_ino is the first |
| member and that the layout of the following members matches exactly in |
| both structures. */ |
| assert (offsetof (struct dirent, d_ino) == 0); |
| assert (offsetof (struct dirent64, d_ino) == 0); |
| # define MATCH(memb) \ |
| assert (offsetof (struct dirent64, memb) - sizeof (entry64->d_ino) \ |
| == offsetof (struct dirent, memb) - sizeof (ino_t)) |
| MATCH (d_reclen); |
| MATCH (d_type); |
| MATCH (d_namlen); |
| # undef MATCH |
| |
| if (entry64 == NULL) |
| return NULL; |
| |
| struct dirent *const entry = ((void *) (&entry64->d_ino + 1) |
| - sizeof entry->d_ino); |
| const ino_t d_ino = entry64->d_ino; |
| if (d_ino != entry64->d_ino) |
| { |
| __set_errno (EOVERFLOW); |
| return NULL; |
| } |
| # if BYTE_ORDER != BIG_ENDIAN /* We just skipped over the zero high word. */ |
| entry->d_ino = d_ino; /* ... or the nonzero low word, swap it. */ |
| # endif |
| entry->d_reclen -= sizeof entry64->d_ino - sizeof entry->d_ino; |
| return entry; |
| } |
| |
| weak_alias (__readdir, readdir) |