Deprecate ustat syscall interface

As for sysctl, ustat has been deprecated in favor of {f}statfs.  Also
some newer ports which uses generic interface builds a stub version that
returns ENOSYS.

This patch deprecates ustat interface by removing ustat.h related headers,
adding a compatibility symbol, and avoiding new ports to build and provide
the symbol.

Checked on x86_64-linux-gnu and i686-linux-gnu.  Also checked with a
check-abi on all affected ABIs.

	* NEWS: Add ustat.h deprecation entry.
	* bits/ustat.h: Remove file.
	* misc/sys/ustat.h: Likewise.
	* misc/ustat.h: Likewise.
	* sysdeps/unix/sysv/linux/generic/ustat.c: Likewise.
	* misc/Makefile (headers): Remove ustat.h and sys/ustat.h.
	* misc/ustat.c (__ustat): Rename to __old_ustat and export only in
	compatibility mode.
	* sysdeps/unix/sysv/linux/ustat.c (__ustat): Likewise.
	* sysdeps/unix/sysv/linux/mips/ustat.c: Define DEV_TO_KDEV and use
	generic Linux implementation.

3 files changed, 42 insertions, 61 deletions

diff --git a/sysdeps/unix/sysv/linux/generic/ustat.c b/sysdeps/unix/sysv/linux/generic/ustat.c
deleted file mode 100644
index d4f9c8996f..0000000000
--- a/sysdeps/unix/sysv/linux/generic/ustat.c
+++ /dev/null
@@ -1,32 +0,0 @@
-/* Copyright (C) 2011-2018 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-   Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011.
-
-   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 <sys/ustat.h>
-
-#include <sysdep.h>
-#include <sys/syscall.h>
-
-/* This deprecated syscall is no longer used (replaced with fstat).  */
-int
-ustat (dev_t dev, struct ustat *ubuf)
-{
-  __set_errno (ENOSYS);
-  return -1;
-}
-stub_warning (ustat)
diff --git a/sysdeps/unix/sysv/linux/mips/ustat.c b/sysdeps/unix/sysv/linux/mips/ustat.c
index 1f597c9363..786a5ef330 100644
--- a/sysdeps/unix/sysv/linux/mips/ustat.c
+++ b/sysdeps/unix/sysv/linux/mips/ustat.c
@@ -16,20 +16,13 @@
    License along with the GNU C Library.  If not, see
    <http://www.gnu.org/licenses/>.  */
 
-#include <errno.h>
-#include <sys/ustat.h>
 #include <sys/sysmacros.h>
 
-#include <sysdep.h>
-#include <sys/syscall.h>
+#define DEV_TO_KDEV(__dev)					\
+  ({								\
+    unsigned long k_dev;					\
+    k_dev = ((major (dev) & 0xff) << 8) | (minor (dev) & 0xff);	\
+    k_dev;							\
+  })
 
-int
-ustat (dev_t dev, struct ustat *ubuf)
-{
-  unsigned long k_dev;
-
-  /* We must convert the value to dev_t type used by the kernel.  */
-  k_dev = ((major (dev) & 0xff) << 8) | (minor (dev) & 0xff);
-
-  return INLINE_SYSCALL (ustat, 2, k_dev, ubuf);
-}
+#include <sysdeps/unix/sysv/linux/ustat.c>
diff --git a/sysdeps/unix/sysv/linux/ustat.c b/sysdeps/unix/sysv/linux/ustat.c
index 8e73faad55..50204e4953 100644
--- a/sysdeps/unix/sysv/linux/ustat.c
+++ b/sysdeps/unix/sysv/linux/ustat.c
@@ -1,4 +1,5 @@
-/* Copyright (C) 1997-2018 Free Software Foundation, Inc.
+/* Get filesystem statistics (deprecated).  Linux version.
+   Copyright (C) 1997-2018 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
 
@@ -16,22 +17,41 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
-#include <errno.h>
-#include <sys/ustat.h>
-#include <sys/sysmacros.h>
+#include <shlib-compat.h>
 
-#include <sysdep.h>
-#include <sys/syscall.h>
+/* This deprecated syscall is no longer used (replaced with {f}statfs).  */
+#if SHLIB_COMPAT(libc, GLIBC_2_0, GLIBC_2_28)
 
-int
-ustat (dev_t dev, struct ustat *ubuf)
-{
-  unsigned long long int k_dev;
+# include <sysdep.h>
+# include <errno.h>
+
+# ifndef DEV_TO_KDEV
+#  define DEV_TO_KDEV(__dev)					\
+  ({								\
+    unsigned long long int k_dev;				\
+    k_dev = dev & ((1ULL << 32) - 1);				\
+    if (k_dev != dev)						\
+     return INLINE_SYSCALL_ERROR_RETURN_VALUE (EINVAL);		\
+    (unsigned int) k_dev;					\
+  })
+# endif
 
-  /* We must convert the value to dev_t type used by the kernel.  */
-  k_dev =  dev & ((1ULL << 32) - 1);
-  if (k_dev != dev)
-    return INLINE_SYSCALL_ERROR_RETURN_VALUE (EINVAL);
+struct ustat
+{
+  __daddr_t f_tfree;         /* Number of free blocks.  */
+  __ino_t f_tinode;          /* Number of free inodes.  */
+  char f_fname[6];
+  char f_fpack[6];
+};
 
-  return INLINE_SYSCALL (ustat, 2, (unsigned int) k_dev, ubuf);
+int
+__old_ustat (dev_t dev, struct ustat *ubuf)
+{
+# ifdef __NR_ustat
+  return INLINE_SYSCALL_CALL (ustat, DEV_TO_KDEV (dev), ubuf);
+# else
+  return INLINE_SYSCALL_ERROR_RETURN_VALUE (ENOSYS);
+# endif
 }
+compat_symbol (libc, __old_ustat, ustat, GLIBC_2_0);
+#endif /* SHLIB_COMPAT(libc, GLIBC_2_0, GLIBC_2_28)  */