[PATCH] Linux: Move getdents64 to <dirent.h>

[Florian Weimer <fweimer at redhat dot com>]

This matches the location of the declaration in musl.

[Passed testing on x86_64-linux-gnu, i686-linux-gnu, and
build-many-glibcs.py (with GCC 9).  I do think we should make this
change before the release because it's going to be the first one with
getdents64.]

2019-07-25  Florian Weimer  <fweimer@redhat.com>

	Linux: Move declaration of getdents64 to <dirent.h>.
	* bits/dirent_ext.h: New file.
	* dirent/Makefile (headers): Add bits/dirent_ext.h.
	* dirent/dirent.h: Include <bits/dirent_ext.h>.
	* sysdeps/unix/sysv/linux/bits/dirent_ext.h: New file.
	* sysdeps/unix/sysv/linux/bits/unistd_ext.h (getdents64): Remove
	declaration.
	* manual/filesys.texi (Low-level Directory Access): Update header
	to dirent.h.

diff --git a/bits/dirent_ext.h b/bits/dirent_ext.h
new file mode 100644
index 0000000000..279fd25d25
--- /dev/null
+++ b/bits/dirent_ext.h
@@ -0,0 +1,21 @@
+/* System-specific extensions of <dirent.h>, generic version.
+   Copyright (C) 2019 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/>.  */
+
+#ifndef _DIRENT_H
+# error "Never include <bits/dirent_ext.h> directly; use <dirent.h> instead."
+#endif
diff --git a/dirent/Makefile b/dirent/Makefile
index b002214c3d..144e448b3d 100644
--- a/dirent/Makefile
+++ b/dirent/Makefile
@@ -22,7 +22,7 @@ subdir		:= dirent
 
 include ../Makeconfig
 
-headers		:= dirent.h bits/dirent.h
+headers		:= dirent.h bits/dirent.h bits/dirent_ext.h
 routines	:= opendir closedir readdir readdir_r rewinddir \
 		   seekdir telldir scandir alphasort versionsort \
 		   getdents getdents64 dirfd readdir64 readdir64_r scandir64 \
diff --git a/dirent/dirent.h b/dirent/dirent.h
index fc4d4859fe..d4650db17e 100644
--- a/dirent/dirent.h
+++ b/dirent/dirent.h
@@ -401,4 +401,6 @@ extern int versionsort64 (const struct dirent64 **__e1,
 
 __END_DECLS
 
+#include <bits/dirent_ext.h>
+
 #endif /* dirent.h  */
diff --git a/manual/filesys.texi b/manual/filesys.texi
index 513319418a..d31dbb24b4 100644
--- a/manual/filesys.texi
+++ b/manual/filesys.texi
@@ -843,7 +843,7 @@ Directory data is obtained from a file descriptor, as created by the
 @xref{Opening and Closing Files}.
 
 @deftypefun ssize_t getdents64 (int @var{fd}, void *@var{buffer}, size_t @var{length})
-@standards{Linux, unistd.h}
+@standards{Linux, dirent.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{getdents64} function reads at most @var{length} bytes of
 directory entry data from the file descriptor @var{fd} and stores it
diff --git a/sysdeps/unix/sysv/linux/bits/dirent_ext.h b/sysdeps/unix/sysv/linux/bits/dirent_ext.h
new file mode 100644
index 0000000000..bac8f95b8f
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/bits/dirent_ext.h
@@ -0,0 +1,33 @@
+/* System-specific extensions of <dirent.h>.  Linux version.
+   Copyright (C) 2019 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/>.  */
+
+#ifndef _DIRENT_H
+# error "Never include <bits/dirent_ext.h> directly; use <dirent.h> instead."
+#endif
+
+__BEGIN_DECLS
+
+#ifdef __USE_GNU
+/* Read from the directory descriptor FD into LENGTH bytes at BUFFER.
+   Return the number of bytes read on success (0 for end of
+   directory), and -1 for failure.  */
+extern __ssize_t getdents64 (int __fd, void *__buffer, size_t __length)
+  __THROW __nonnull ((2));
+#endif
+
+__END_DECLS
diff --git a/sysdeps/unix/sysv/linux/bits/unistd_ext.h b/sysdeps/unix/sysv/linux/bits/unistd_ext.h
index 6e7b2bb83d..0061172f23 100644
--- a/sysdeps/unix/sysv/linux/bits/unistd_ext.h
+++ b/sysdeps/unix/sysv/linux/bits/unistd_ext.h
@@ -22,12 +22,6 @@
 
 #ifdef __USE_GNU
 
-/* Read from the directory descriptor FD into LENGTH bytes at BUFFER.
-   Return the number of bytes read on success (0 for end of
-   directory), and -1 for failure.  */
-extern ssize_t getdents64 (int __fd, void *__buffer, size_t __length)
-  __THROW __nonnull ((2));
-
 /* Return the kernel thread ID (TID) of the current thread.  The
    returned value is not subject to caching.  Most Linux system calls
    accept a TID in place of a PID.  Using the TID to change properties