Update copyright dates with scripts/update-copyrights.

[thirdparty/glibc.git] / sysdeps / mach / hurd / readdir.c

diff --git a/sysdeps/mach/hurd/readdir.c b/sysdeps/mach/hurd/readdir.c
index 185aeee2b13ca77d1e7b21948942f057629e8aec..147a0bc4690a20626b4cda3d5358f3801065943b 100644 (file)
--- a/sysdeps/mach/hurd/readdir.c
+++ b/sysdeps/mach/hurd/readdir.c
@@ -1,90 +1,66 @@
-/* Copyright (C) 1993, 1994 Free Software Foundation, Inc.
-This file is part of the GNU C Library.
+/* Copyright (C) 1993-2017 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 Library General Public License as
-published by the Free Software Foundation; either version 2 of the
-License, or (at your option) any later version.
+   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
-Library General Public License for more details.
+   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 Library General Public
-License along with the GNU C Library; see the file COPYING.LIB.  If
-not, write to the Free Software Foundation, Inc., 675 Mass Ave,
-Cambridge, MA 02139, USA.  */
+   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 <ansidecl.h>
 #include <errno.h>
-#include <limits.h>
 #include <stddef.h>
-#include <string.h>
 #include <dirent.h>
 #include <unistd.h>
-#include <sys/types.h>
-#include <hurd.h>
-
+#include <endian.h>
+#include <assert.h>
 
 /* Read a directory entry from DIRP.  */
 struct dirent *
-DEFUN(readdir, (dirp), DIR *dirp)
+__readdir (DIR *dirp)
 {
-  struct dirent *dp;
-
-  if (dirp == NULL)
+  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)
     {
-      errno = EINVAL;
+      __set_errno (EOVERFLOW);
       return NULL;
     }
-
-  do
-    {
-      if (dirp->__ptr - dirp->__data >= dirp->__size)
-       {
-         /* We've emptied out our buffer.  Refill it.  */
-
-         char *data = dirp->__data;
-         int nentries;
-         error_t err;
-
-         if (err = __dir_readdir (dirp->__port, &data, &dirp->__size,
-                                  dirp->__entry_ptr, -1, 0, &nentries))
-           return __hurd_fail (err), NULL;
-
-         /* DATA now corresponds to entry index DIRP->__entry_ptr.  */
-         dirp->__entry_data = dirp->__entry_ptr;
-
-         if (data != dirp->__data)
-           {
-             /* The data was passed out of line, so our old buffer is no
-                longer useful.  Deallocate the old buffer and reset our
-                information for the new buffer.  */
-             __vm_deallocate (__mach_task_self (),
-                              (vm_address_t) dirp->__data,
-                              dirp->__allocation);
-             dirp->__data = data;
-             dirp->__allocation = round_page (dirp->__size);
-           }
-
-         /* Reset the pointer into the buffer.  */
-         dirp->__ptr = dirp->__data;
-
-         if (nentries == 0)
-           /* End of file.  */
-           return NULL;
-
-         /* We trust the filesystem to return correct data and so we
-            ignore NENTRIES.  */
-       }
-
-      dp = (struct dirent *) dirp->__ptr;
-      dirp->__ptr += dp->d_reclen;
-      ++dirp->__entry_ptr;
-
-      /* Loop to ignore deleted files.  */
-    } while (dp->d_fileno == 0);
-
-  return dp;
+# 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)