linux: Move posix dir implementations to Linux

This generic implementation already expects a getdents API which
is Linux specific.  It also allows simplify it by assuming
_DIRENT_HAVE_D_RECLEN and _DIRENT_HAVE_D_OFF support.

The readdir are also expanded on each required implementation,
futher fixes and improvements will make parametrize the
implementation more complex.

Checked on x86_64-linux-gnu, i686-linux-gnu, and with a build
for all affected ABIs.

14 files changed, 462 insertions, 309 deletions

diff --git a/sysdeps/posix/readdir.c b/sysdeps/posix/readdir.c
deleted file mode 100644
index b36278b5f4..0000000000
--- a/sysdeps/posix/readdir.c
+++ /dev/null
@@ -1,127 +0,0 @@
-/* Copyright (C) 1991-2020 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
-   <https://www.gnu.org/licenses/>.  */
-
-#include <errno.h>
-#include <limits.h>
-#include <stddef.h>
-#include <string.h>
-#include <dirent.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <assert.h>
-
-#include <dirstream.h>
-
-#ifndef __READDIR
-# define __READDIR __readdir
-# define __GETDENTS __getdents
-# define DIRENT_TYPE struct dirent
-# define __READDIR_ALIAS
-#endif
-
-/* Read a directory entry from DIRP.  */
-DIRENT_TYPE *
-__READDIR (DIR *dirp)
-{
-  DIRENT_TYPE *dp;
-  int saved_errno = errno;
-
-#if IS_IN (libc)
-  __libc_lock_lock (dirp->lock);
-#endif
-
-  do
-    {
-      size_t reclen;
-
-      if (dirp->offset >= dirp->size)
-	{
-	  /* We've emptied out our buffer.  Refill it.  */
-
-	  size_t maxread;
-	  ssize_t bytes;
-
-#ifndef _DIRENT_HAVE_D_RECLEN
-	  /* Fixed-size struct; must read one at a time (see below).  */
-	  maxread = sizeof *dp;
-#else
-	  maxread = dirp->allocation;
-#endif
-
-	  bytes = __GETDENTS (dirp->fd, dirp->data, maxread);
-	  if (bytes <= 0)
-	    {
-	      /* On some systems getdents fails with ENOENT when the
-		 open directory has been rmdir'd already.  POSIX.1
-		 requires that we treat this condition like normal EOF.  */
-	      if (bytes < 0 && errno == ENOENT)
-		bytes = 0;
-
-	      /* Don't modifiy errno when reaching EOF.  */
-	      if (bytes == 0)
-		__set_errno (saved_errno);
-	      dp = NULL;
-	      break;
-	    }
-	  dirp->size = (size_t) bytes;
-
-	  /* Reset the offset into the buffer.  */
-	  dirp->offset = 0;
-	}
-
-      dp = (DIRENT_TYPE *) &dirp->data[dirp->offset];
-
-#ifdef _DIRENT_HAVE_D_RECLEN
-      reclen = dp->d_reclen;
-#else
-      /* The only version of `struct dirent*' that lacks `d_reclen'
-	 is fixed-size.  */
-      assert (sizeof dp->d_name > 1);
-      reclen = sizeof *dp;
-      /* The name is not terminated if it is the largest possible size.
-	 Clobber the following byte to ensure proper null termination.  We
-	 read jst one entry at a time above so we know that byte will not
-	 be used later.  */
-      dp->d_name[sizeof dp->d_name] = '\0';
-#endif
-
-      dirp->offset += reclen;
-
-#ifdef _DIRENT_HAVE_D_OFF
-      dirp->filepos = dp->d_off;
-#else
-      dirp->filepos += reclen;
-#endif
-
-      /* Skip deleted files.  */
-    } while (dp->d_ino == 0);
-
-#if IS_IN (libc)
-  __libc_lock_unlock (dirp->lock);
-#endif
-
-  return dp;
-}
-
-#ifdef __READDIR_ALIAS
-weak_alias (__readdir, readdir)
-#endif
-
-#undef __READDIR
-#undef __GETDENTS
-#undef DIRENT_TYPE
-#undef __READDIR_ALIAS
diff --git a/sysdeps/posix/readdir_r.c b/sysdeps/posix/readdir_r.c
deleted file mode 100644
index 9079abc2ff..0000000000
--- a/sysdeps/posix/readdir_r.c
+++ /dev/null
@@ -1,159 +0,0 @@
-/* Copyright (C) 1991-2020 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
-   <https://www.gnu.org/licenses/>.  */
-
-#include <errno.h>
-#include <limits.h>
-#include <stddef.h>
-#include <string.h>
-#include <dirent.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <assert.h>
-
-#include <dirstream.h>
-
-#ifndef __READDIR_R
-# define __READDIR_R __readdir_r
-# define __GETDENTS __getdents
-# define DIRENT_TYPE struct dirent
-# define __READDIR_R_ALIAS
-#endif
-
-/* Read a directory entry from DIRP.  */
-int
-__READDIR_R (DIR *dirp, DIRENT_TYPE *entry, DIRENT_TYPE **result)
-{
-  DIRENT_TYPE *dp;
-  size_t reclen;
-  const int saved_errno = errno;
-  int ret;
-
-  __libc_lock_lock (dirp->lock);
-
-  do
-    {
-      if (dirp->offset >= dirp->size)
-	{
-	  /* We've emptied out our buffer.  Refill it.  */
-
-	  size_t maxread;
-	  ssize_t bytes;
-
-#ifndef _DIRENT_HAVE_D_RECLEN
-	  /* Fixed-size struct; must read one at a time (see below).  */
-	  maxread = sizeof *dp;
-#else
-	  maxread = dirp->allocation;
-#endif
-
-	  bytes = __GETDENTS (dirp->fd, dirp->data, maxread);
-	  if (bytes <= 0)
-	    {
-	      /* On some systems getdents fails with ENOENT when the
-		 open directory has been rmdir'd already.  POSIX.1
-		 requires that we treat this condition like normal EOF.  */
-	      if (bytes < 0 && errno == ENOENT)
-		{
-		  bytes = 0;
-		  __set_errno (saved_errno);
-		}
-	      if (bytes < 0)
-		dirp->errcode = errno;
-
-	      dp = NULL;
-	      break;
-	    }
-	  dirp->size = (size_t) bytes;
-
-	  /* Reset the offset into the buffer.  */
-	  dirp->offset = 0;
-	}
-
-      dp = (DIRENT_TYPE *) &dirp->data[dirp->offset];
-
-#ifdef _DIRENT_HAVE_D_RECLEN
-      reclen = dp->d_reclen;
-#else
-      /* The only version of `struct dirent*' that lacks `d_reclen'
-	 is fixed-size.  */
-      assert (sizeof dp->d_name > 1);
-      reclen = sizeof *dp;
-      /* The name is not terminated if it is the largest possible size.
-	 Clobber the following byte to ensure proper null termination.  We
-	 read just one entry at a time above so we know that byte will not
-	 be used later.  */
-      dp->d_name[sizeof dp->d_name] = '\0';
-#endif
-
-      dirp->offset += reclen;
-
-#ifdef _DIRENT_HAVE_D_OFF
-      dirp->filepos = dp->d_off;
-#else
-      dirp->filepos += reclen;
-#endif
-
-#ifdef NAME_MAX
-      if (reclen > offsetof (DIRENT_TYPE, d_name) + NAME_MAX + 1)
-	{
-	  /* The record is very long.  It could still fit into the
-	     caller-supplied buffer if we can skip padding at the
-	     end.  */
-	  size_t namelen = _D_EXACT_NAMLEN (dp);
-	  if (namelen <= NAME_MAX)
-	    reclen = offsetof (DIRENT_TYPE, d_name) + namelen + 1;
-	  else
-	    {
-	      /* The name is too long.  Ignore this file.  */
-	      dirp->errcode = ENAMETOOLONG;
-	      dp->d_ino = 0;
-	      continue;
-	    }
-	}
-#endif
-
-      /* Skip deleted and ignored files.  */
-    }
-  while (dp->d_ino == 0);
-
-  if (dp != NULL)
-    {
-      *result = memcpy (entry, dp, reclen);
-#ifdef _DIRENT_HAVE_D_RECLEN
-      entry->d_reclen = reclen;
-#endif
-      ret = 0;
-    }
-  else
-    {
-      *result = NULL;
-      ret = dirp->errcode;
-    }
-
-  __libc_lock_unlock (dirp->lock);
-
-  return ret;
-}
-
-#ifdef __READDIR_R_ALIAS
-weak_alias (__readdir_r, readdir_r)
-#endif
-
-#undef __READDIR_R
-#undef __GETDENTS
-#undef DIRENT_TYPE
-#undef __READDIR_R_ALIAS
diff --git a/sysdeps/posix/closedir.c b/sysdeps/unix/sysv/linux/closedir.c
index ccc19eefcd..ccc19eefcd 100644
--- a/sysdeps/posix/closedir.c
+++ b/sysdeps/unix/sysv/linux/closedir.c
diff --git a/sysdeps/posix/dirfd.c b/sysdeps/unix/sysv/linux/dirfd.c
index 5d0928dca4..5d0928dca4 100644
--- a/sysdeps/posix/dirfd.c
+++ b/sysdeps/unix/sysv/linux/dirfd.c
diff --git a/sysdeps/posix/dirstream.h b/sysdeps/unix/sysv/linux/dirstream.h
index a3ea2b7197..a3ea2b7197 100644
--- a/sysdeps/posix/dirstream.h
+++ b/sysdeps/unix/sysv/linux/dirstream.h
diff --git a/sysdeps/posix/fdopendir.c b/sysdeps/unix/sysv/linux/fdopendir.c
index e424fbdaa2..e424fbdaa2 100644
--- a/sysdeps/posix/fdopendir.c
+++ b/sysdeps/unix/sysv/linux/fdopendir.c
diff --git a/sysdeps/posix/opendir.c b/sysdeps/unix/sysv/linux/opendir.c
index e89e09bfc7..e89e09bfc7 100644
--- a/sysdeps/posix/opendir.c
+++ b/sysdeps/unix/sysv/linux/opendir.c
diff --git a/sysdeps/unix/sysv/linux/readdir.c b/sysdeps/unix/sysv/linux/readdir.c
index df7a92aa78..2e03e66e69 100644
--- a/sysdeps/unix/sysv/linux/readdir.c
+++ b/sysdeps/unix/sysv/linux/readdir.c
@@ -19,5 +19,68 @@
 #include <dirent.h>
 
 #if !_DIRENT_MATCHES_DIRENT64
-# include <sysdeps/posix/readdir.c>
+#include <dirstream.h>
+
+/* Read a directory entry from DIRP.  */
+struct dirent *
+__readdir (DIR *dirp)
+{
+  struct dirent *dp;
+  int saved_errno = errno;
+
+#if IS_IN (libc)
+  __libc_lock_lock (dirp->lock);
+#endif
+
+  do
+    {
+      size_t reclen;
+
+      if (dirp->offset >= dirp->size)
+	{
+	  /* We've emptied out our buffer.  Refill it.  */
+
+	  size_t maxread = dirp->allocation;
+	  ssize_t bytes;
+
+	  bytes = __getdents (dirp->fd, dirp->data, maxread);
+	  if (bytes <= 0)
+	    {
+	      /* On some systems getdents fails with ENOENT when the
+		 open directory has been rmdir'd already.  POSIX.1
+		 requires that we treat this condition like normal EOF.  */
+	      if (bytes < 0 && errno == ENOENT)
+		bytes = 0;
+
+	      /* Don't modifiy errno when reaching EOF.  */
+	      if (bytes == 0)
+		__set_errno (saved_errno);
+	      dp = NULL;
+	      break;
+	    }
+	  dirp->size = (size_t) bytes;
+
+	  /* Reset the offset into the buffer.  */
+	  dirp->offset = 0;
+	}
+
+      dp = (struct dirent *) &dirp->data[dirp->offset];
+
+      reclen = dp->d_reclen;
+
+      dirp->offset += reclen;
+
+      dirp->filepos = dp->d_off;
+
+      /* Skip deleted files.  */
+    } while (dp->d_ino == 0);
+
+#if IS_IN (libc)
+  __libc_lock_unlock (dirp->lock);
+#endif
+
+  return dp;
+}
+weak_alias (__readdir, readdir)
+
 #endif
diff --git a/sysdeps/unix/sysv/linux/readdir64.c b/sysdeps/unix/sysv/linux/readdir64.c
index 170a889c51..1aa6e2664f 100644
--- a/sysdeps/unix/sysv/linux/readdir64.c
+++ b/sysdeps/unix/sysv/linux/readdir64.c
@@ -23,17 +23,71 @@
 #define readdir   __no_readdir_decl
 #define __readdir __no___readdir_decl
 #include <dirent.h>
+#undef __readdir
+#undef readdir
 
-#define __READDIR   __readdir64
-#define __GETDENTS  __getdents64
-#define DIRENT_TYPE struct dirent64
+/* Read a directory entry from DIRP.  */
+struct dirent64 *
+__readdir64 (DIR *dirp)
+{
+  struct dirent64 *dp;
+  int saved_errno = errno;
 
-#include <sysdeps/posix/readdir.c>
+#if IS_IN (libc)
+  __libc_lock_lock (dirp->lock);
+#endif
 
-#undef __readdir
-#undef readdir
+  do
+    {
+      size_t reclen;
+
+      if (dirp->offset >= dirp->size)
+	{
+	  /* We've emptied out our buffer.  Refill it.  */
+
+	  size_t maxread = dirp->allocation;
+	  ssize_t bytes;
+
+	  bytes = __getdents64 (dirp->fd, dirp->data, maxread);
+	  if (bytes <= 0)
+	    {
+	      /* On some systems getdents fails with ENOENT when the
+		 open directory has been rmdir'd already.  POSIX.1
+		 requires that we treat this condition like normal EOF.  */
+	      if (bytes < 0 && errno == ENOENT)
+		bytes = 0;
+
+	      /* Don't modifiy errno when reaching EOF.  */
+	      if (bytes == 0)
+		__set_errno (saved_errno);
+	      dp = NULL;
+	      break;
+	    }
+	  dirp->size = (size_t) bytes;
 
+	  /* Reset the offset into the buffer.  */
+	  dirp->offset = 0;
+	}
+
+      dp = (struct dirent64 *) &dirp->data[dirp->offset];
+
+      reclen = dp->d_reclen;
+
+      dirp->offset += reclen;
+
+      dirp->filepos = dp->d_off;
+
+      /* Skip deleted files.  */
+    } while (dp->d_ino == 0);
+
+#if IS_IN (libc)
+  __libc_lock_unlock (dirp->lock);
+#endif
+
+  return dp;
+}
 libc_hidden_def (__readdir64)
+
 #if _DIRENT_MATCHES_DIRENT64
 strong_alias (__readdir64, __readdir)
 weak_alias (__readdir64, readdir64)
@@ -49,10 +103,67 @@ versioned_symbol (libc, __readdir64, readdir64, GLIBC_2_2);
 # endif
 # if SHLIB_COMPAT(libc, GLIBC_2_1, GLIBC_2_2)
 #  include <olddirent.h>
-#  define __READDIR   attribute_compat_text_section __old_readdir64
-#  define __GETDENTS  __old_getdents64
-#  define DIRENT_TYPE struct __old_dirent64
-#  include <sysdeps/posix/readdir.c>
+
+attribute_compat_text_section
+struct __old_dirent64 *
+__old_readdir64 (DIR *dirp)
+{
+  struct __old_dirent64 *dp;
+  int saved_errno = errno;
+
+#if IS_IN (libc)
+  __libc_lock_lock (dirp->lock);
+#endif
+
+  do
+    {
+      size_t reclen;
+
+      if (dirp->offset >= dirp->size)
+	{
+	  /* We've emptied out our buffer.  Refill it.  */
+
+	  size_t maxread = dirp->allocation;
+	  ssize_t bytes;
+
+	  bytes = __old_getdents64 (dirp->fd, dirp->data, maxread);
+	  if (bytes <= 0)
+	    {
+	      /* On some systems getdents fails with ENOENT when the
+		 open directory has been rmdir'd already.  POSIX.1
+		 requires that we treat this condition like normal EOF.  */
+	      if (bytes < 0 && errno == ENOENT)
+		bytes = 0;
+
+	      /* Don't modifiy errno when reaching EOF.  */
+	      if (bytes == 0)
+		__set_errno (saved_errno);
+	      dp = NULL;
+	      break;
+	    }
+	  dirp->size = (size_t) bytes;
+
+	  /* Reset the offset into the buffer.  */
+	  dirp->offset = 0;
+	}
+
+      dp = (struct __old_dirent64 *) &dirp->data[dirp->offset];
+
+      reclen = dp->d_reclen;
+
+      dirp->offset += reclen;
+
+      dirp->filepos = dp->d_off;
+
+      /* Skip deleted files.  */
+    } while (dp->d_ino == 0);
+
+#if IS_IN (libc)
+  __libc_lock_unlock (dirp->lock);
+#endif
+
+  return dp;
+}
 libc_hidden_def (__old_readdir64)
 compat_symbol (libc, __old_readdir64, readdir64, GLIBC_2_1);
 # endif /* SHLIB_COMPAT(libc, GLIBC_2_1, GLIBC_2_2)  */
diff --git a/sysdeps/unix/sysv/linux/readdir64_r.c b/sysdeps/unix/sysv/linux/readdir64_r.c
index 6d589f36f5..c587787417 100644
--- a/sysdeps/unix/sysv/linux/readdir64_r.c
+++ b/sysdeps/unix/sysv/linux/readdir64_r.c
@@ -23,15 +23,100 @@
 #define readdir_r   __no_readdir_r_decl
 #define __readdir_r __no___readdir_r_decl
 #include <dirent.h>
+#undef __readdir_r
+#undef readdir_r
 
-#define __READDIR_R __readdir64_r
-#define __GETDENTS  __getdents64
-#define DIRENT_TYPE struct dirent64
+/* Read a directory entry from DIRP.  */
+int
+__readdir64_r (DIR *dirp, struct dirent64 *entry, struct dirent64 **result)
+{
+  struct dirent64 *dp;
+  size_t reclen;
+  const int saved_errno = errno;
+  int ret;
 
-#include <sysdeps/posix/readdir_r.c>
+  __libc_lock_lock (dirp->lock);
+
+  do
+    {
+      if (dirp->offset >= dirp->size)
+	{
+	  /* We've emptied out our buffer.  Refill it.  */
+
+	  size_t maxread = dirp->allocation;
+	  ssize_t bytes;
+
+	  maxread = dirp->allocation;
+
+	  bytes = __getdents64 (dirp->fd, dirp->data, maxread);
+	  if (bytes <= 0)
+	    {
+	      /* On some systems getdents fails with ENOENT when the
+		 open directory has been rmdir'd already.  POSIX.1
+		 requires that we treat this condition like normal EOF.  */
+	      if (bytes < 0 && errno == ENOENT)
+		{
+		  bytes = 0;
+		  __set_errno (saved_errno);
+		}
+	      if (bytes < 0)
+		dirp->errcode = errno;
+
+	      dp = NULL;
+	      break;
+	    }
+	  dirp->size = (size_t) bytes;
+
+	  /* Reset the offset into the buffer.  */
+	  dirp->offset = 0;
+	}
+
+      dp = (struct dirent64 *) &dirp->data[dirp->offset];
+
+      reclen = dp->d_reclen;
+
+      dirp->offset += reclen;
+
+      dirp->filepos = dp->d_off;
+
+      if (reclen > offsetof (struct dirent64, d_name) + NAME_MAX + 1)
+	{
+	  /* The record is very long.  It could still fit into the
+	     caller-supplied buffer if we can skip padding at the
+	     end.  */
+	  size_t namelen = _D_EXACT_NAMLEN (dp);
+	  if (namelen <= NAME_MAX)
+	    reclen = offsetof (struct dirent64, d_name) + namelen + 1;
+	  else
+	    {
+	      /* The name is too long.  Ignore this file.  */
+	      dirp->errcode = ENAMETOOLONG;
+	      dp->d_ino = 0;
+	      continue;
+	    }
+	}
+
+      /* Skip deleted and ignored files.  */
+    }
+  while (dp->d_ino == 0);
+
+  if (dp != NULL)
+    {
+      *result = memcpy (entry, dp, reclen);
+      entry->d_reclen = reclen;
+      ret = 0;
+    }
+  else
+    {
+      *result = NULL;
+      ret = dirp->errcode;
+    }
+
+  __libc_lock_unlock (dirp->lock);
+
+  return ret;
+}
 
-#undef __readdir_r
-#undef readdir_r
 
 #if _DIRENT_MATCHES_DIRENT64
 strong_alias (__readdir64_r, __readdir_r)
@@ -44,10 +129,99 @@ weak_alias (__readdir64_r, readdir64_r)
 versioned_symbol (libc, __readdir64_r, readdir64_r, GLIBC_2_2);
 # if SHLIB_COMPAT(libc, GLIBC_2_1, GLIBC_2_2)
 #  include <olddirent.h>
-#  define __READDIR_R attribute_compat_text_section __old_readdir64_r
-#  define __GETDENTS  __old_getdents64
-#  define DIRENT_TYPE struct __old_dirent64
-#  include <sysdeps/posix/readdir_r.c>
+
+int
+attribute_compat_text_section
+__old_readdir64_r (DIR *dirp, struct __old_dirent64 *entry,
+		   struct __old_dirent64 **result)
+{
+  struct __old_dirent64 *dp;
+  size_t reclen;
+  const int saved_errno = errno;
+  int ret;
+
+  __libc_lock_lock (dirp->lock);
+
+  do
+    {
+      if (dirp->offset >= dirp->size)
+	{
+	  /* We've emptied out our buffer.  Refill it.  */
+
+	  size_t maxread = dirp->allocation;
+	  ssize_t bytes;
+
+	  maxread = dirp->allocation;
+
+	  bytes = __old_getdents64 (dirp->fd, dirp->data, maxread);
+	  if (bytes <= 0)
+	    {
+	      /* On some systems getdents fails with ENOENT when the
+		 open directory has been rmdir'd already.  POSIX.1
+		 requires that we treat this condition like normal EOF.  */
+	      if (bytes < 0 && errno == ENOENT)
+		{
+		  bytes = 0;
+		  __set_errno (saved_errno);
+		}
+	      if (bytes < 0)
+		dirp->errcode = errno;
+
+	      dp = NULL;
+	      break;
+	    }
+	  dirp->size = (size_t) bytes;
+
+	  /* Reset the offset into the buffer.  */
+	  dirp->offset = 0;
+	}
+
+      dp = (struct __old_dirent64 *) &dirp->data[dirp->offset];
+
+      reclen = dp->d_reclen;
+
+      dirp->offset += reclen;
+
+      dirp->filepos = dp->d_off;
+
+      if (reclen > offsetof (struct __old_dirent64, d_name) + NAME_MAX + 1)
+	{
+	  /* The record is very long.  It could still fit into the
+	     caller-supplied buffer if we can skip padding at the
+	     end.  */
+	  size_t namelen = _D_EXACT_NAMLEN (dp);
+	  if (namelen <= NAME_MAX)
+	    reclen = offsetof (struct __old_dirent64, d_name) + namelen + 1;
+	  else
+	    {
+	      /* The name is too long.  Ignore this file.  */
+	      dirp->errcode = ENAMETOOLONG;
+	      dp->d_ino = 0;
+	      continue;
+	    }
+	}
+
+      /* Skip deleted and ignored files.  */
+    }
+  while (dp->d_ino == 0);
+
+  if (dp != NULL)
+    {
+      *result = memcpy (entry, dp, reclen);
+      entry->d_reclen = reclen;
+      ret = 0;
+    }
+  else
+    {
+      *result = NULL;
+      ret = dirp->errcode;
+    }
+
+  __libc_lock_unlock (dirp->lock);
+
+  return ret;
+}
+
 compat_symbol (libc, __old_readdir64_r, readdir64_r, GLIBC_2_1);
 # endif /* SHLIB_COMPAT(libc, GLIBC_2_1, GLIBC_2_2)  */
 #endif /* _DIRENT_MATCHES_DIRENT64  */
diff --git a/sysdeps/unix/sysv/linux/readdir_r.c b/sysdeps/unix/sysv/linux/readdir_r.c
index 30f237dbcc..0069041394 100644
--- a/sysdeps/unix/sysv/linux/readdir_r.c
+++ b/sysdeps/unix/sysv/linux/readdir_r.c
@@ -19,5 +19,96 @@
 #include <dirent.h>
 
 #if !_DIRENT_MATCHES_DIRENT64
-# include <sysdeps/posix/readdir_r.c>
-#endif
+/* Read a directory entry from DIRP.  */
+int
+__readdir_r (DIR *dirp, struct dirent *entry, struct dirent **result)
+{
+  struct dirent *dp;
+  size_t reclen;
+  const int saved_errno = errno;
+  int ret;
+
+  __libc_lock_lock (dirp->lock);
+
+  do
+    {
+      if (dirp->offset >= dirp->size)
+	{
+	  /* We've emptied out our buffer.  Refill it.  */
+
+	  size_t maxread = dirp->allocation;
+	  ssize_t bytes;
+
+	  maxread = dirp->allocation;
+
+	  bytes = __getdents (dirp->fd, dirp->data, maxread);
+	  if (bytes <= 0)
+	    {
+	      /* On some systems getdents fails with ENOENT when the
+		 open directory has been rmdir'd already.  POSIX.1
+		 requires that we treat this condition like normal EOF.  */
+	      if (bytes < 0 && errno == ENOENT)
+		{
+		  bytes = 0;
+		  __set_errno (saved_errno);
+		}
+	      if (bytes < 0)
+		dirp->errcode = errno;
+
+	      dp = NULL;
+	      break;
+	    }
+	  dirp->size = (size_t) bytes;
+
+	  /* Reset the offset into the buffer.  */
+	  dirp->offset = 0;
+	}
+
+      dp = (struct dirent *) &dirp->data[dirp->offset];
+
+      reclen = dp->d_reclen;
+
+      dirp->offset += reclen;
+
+      dirp->filepos = dp->d_off;
+
+      if (reclen > offsetof (struct dirent, d_name) + NAME_MAX + 1)
+	{
+	  /* The record is very long.  It could still fit into the
+	     caller-supplied buffer if we can skip padding at the
+	     end.  */
+	  size_t namelen = _D_EXACT_NAMLEN (dp);
+	  if (namelen <= NAME_MAX)
+	    reclen = offsetof (struct dirent, d_name) + namelen + 1;
+	  else
+	    {
+	      /* The name is too long.  Ignore this file.  */
+	      dirp->errcode = ENAMETOOLONG;
+	      dp->d_ino = 0;
+	      continue;
+	    }
+	}
+
+      /* Skip deleted and ignored files.  */
+    }
+  while (dp->d_ino == 0);
+
+  if (dp != NULL)
+    {
+      *result = memcpy (entry, dp, reclen);
+      entry->d_reclen = reclen;
+      ret = 0;
+    }
+  else
+    {
+      *result = NULL;
+      ret = dirp->errcode;
+    }
+
+  __libc_lock_unlock (dirp->lock);
+
+  return ret;
+}
+
+weak_alias (__readdir_r, readdir_r)
+#endif /* _DIRENT_MATCHES_DIRENT64  */
diff --git a/sysdeps/posix/rewinddir.c b/sysdeps/unix/sysv/linux/rewinddir.c
index 860bfda004..860bfda004 100644
--- a/sysdeps/posix/rewinddir.c
+++ b/sysdeps/unix/sysv/linux/rewinddir.c
diff --git a/sysdeps/posix/seekdir.c b/sysdeps/unix/sysv/linux/seekdir.c
index 3c30520928..3c30520928 100644
--- a/sysdeps/posix/seekdir.c
+++ b/sysdeps/unix/sysv/linux/seekdir.c
diff --git a/sysdeps/posix/telldir.c b/sysdeps/unix/sysv/linux/telldir.c
index 57d435ed21..57d435ed21 100644
--- a/sysdeps/posix/telldir.c
+++ b/sysdeps/unix/sysv/linux/telldir.c