Linux: Use in-tree copy of SO_ constants for !__USE_MISC [BZ #24532]

The kernel changes for a 64-bit time_t on 32-bit architectures
resulted in <asm/socket.h> indirectly including <linux/posix_types.h>.
The latter is not namespace-clean for the POSIX version of
<sys/socket.h>.

This issue has persisted across several Linux releases, so this commit
creates our own copy of the SO_* definitions for !__USE_MISC mode.

The new test socket/tst-socket-consts ensures that the copy is
consistent with the kernel definitions (which vary across
architectures).  The test is tricky to get right because CPPFLAGS
includes include/libc-symbols.h, which in turn defines _GNU_SOURCE
unconditionally.

Tested with build-many-glibcs.py.  I verified that a discrepancy in
the definitions actually results in a failure of the
socket/tst-socket-consts test.

2 files changed, 44 insertions, 92 deletions

diff --git a/sysdeps/unix/sysv/linux/bits/socket-constants.h b/sysdeps/unix/sysv/linux/bits/socket-constants.h
new file mode 100644
index 0000000000..b231342102
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/bits/socket-constants.h
@@ -0,0 +1,38 @@
+/* Socket constants which vary among Linux architectures.
+   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 _SYS_SOCKET_H
+# error "Never include <bits/socket-constants.h> directly; use <sys/socket.h> instead."
+#endif
+
+#define SOL_SOCKET 1
+#define SO_ACCEPTCONN 30
+#define SO_BROADCAST 6
+#define SO_DONTROUTE 5
+#define SO_ERROR 4
+#define SO_KEEPALIVE 9
+#define SO_LINGER 13
+#define SO_OOBINLINE 10
+#define SO_RCVBUF 8
+#define SO_RCVLOWAT 18
+#define SO_RCVTIMEO 20
+#define SO_REUSEADDR 2
+#define SO_SNDBUF 7
+#define SO_SNDLOWAT 19
+#define SO_SNDTIMEO 21
+#define SO_TYPE 3
diff --git a/sysdeps/unix/sysv/linux/bits/socket.h b/sysdeps/unix/sysv/linux/bits/socket.h
index 99af01d2a4..082f8b9031 100644
--- a/sysdeps/unix/sysv/linux/bits/socket.h
+++ b/sysdeps/unix/sysv/linux/bits/socket.h
@@ -349,98 +349,12 @@ struct ucred
 };
 #endif
 
-/* Ugly workaround for unclean kernel headers.  */
-#ifndef __USE_MISC
-# ifndef FIOGETOWN
-#  define __SYS_SOCKET_H_undef_FIOGETOWN
-# endif
-# ifndef FIOSETOWN
-#  define __SYS_SOCKET_H_undef_FIOSETOWN
-# endif
-# ifndef SIOCATMARK
-#  define __SYS_SOCKET_H_undef_SIOCATMARK
-# endif
-# ifndef SIOCGPGRP
-#  define __SYS_SOCKET_H_undef_SIOCGPGRP
-# endif
-# ifndef SIOCGSTAMP
-#  define __SYS_SOCKET_H_undef_SIOCGSTAMP
-# endif
-# ifndef SIOCGSTAMPNS
-#  define __SYS_SOCKET_H_undef_SIOCGSTAMPNS
-# endif
-# ifndef SIOCSPGRP
-#  define __SYS_SOCKET_H_undef_SIOCSPGRP
-# endif
-#endif
-#ifndef IOCSIZE_MASK
-# define __SYS_SOCKET_H_undef_IOCSIZE_MASK
-#endif
-#ifndef IOCSIZE_SHIFT
-# define __SYS_SOCKET_H_undef_IOCSIZE_SHIFT
-#endif
-#ifndef IOC_IN
-# define __SYS_SOCKET_H_undef_IOC_IN
-#endif
-#ifndef IOC_INOUT
-# define __SYS_SOCKET_H_undef_IOC_INOUT
-#endif
-#ifndef IOC_OUT
-# define __SYS_SOCKET_H_undef_IOC_OUT
-#endif
-
-/* Get socket manipulation related informations from kernel headers.  */
-#include <asm/socket.h>
-
-#ifndef __USE_MISC
-# ifdef __SYS_SOCKET_H_undef_FIOGETOWN
-#  undef __SYS_SOCKET_H_undef_FIOGETOWN
-#  undef FIOGETOWN
-# endif
-# ifdef __SYS_SOCKET_H_undef_FIOSETOWN
-#  undef __SYS_SOCKET_H_undef_FIOSETOWN
-#  undef FIOSETOWN
-# endif
-# ifdef __SYS_SOCKET_H_undef_SIOCATMARK
-#  undef __SYS_SOCKET_H_undef_SIOCATMARK
-#  undef SIOCATMARK
-# endif
-# ifdef __SYS_SOCKET_H_undef_SIOCGPGRP
-#  undef __SYS_SOCKET_H_undef_SIOCGPGRP
-#  undef SIOCGPGRP
-# endif
-# ifdef __SYS_SOCKET_H_undef_SIOCGSTAMP
-#  undef __SYS_SOCKET_H_undef_SIOCGSTAMP
-#  undef SIOCGSTAMP
-# endif
-# ifdef __SYS_SOCKET_H_undef_SIOCGSTAMPNS
-#  undef __SYS_SOCKET_H_undef_SIOCGSTAMPNS
-#  undef SIOCGSTAMPNS
-# endif
-# ifdef __SYS_SOCKET_H_undef_SIOCSPGRP
-#  undef __SYS_SOCKET_H_undef_SIOCSPGRP
-#  undef SIOCSPGRP
-# endif
-#endif
-#ifdef __SYS_SOCKET_H_undef_IOCSIZE_MASK
-# undef __SYS_SOCKET_H_undef_IOCSIZE_MASK
-# undef IOCSIZE_MASK
-#endif
-#ifdef __SYS_SOCKET_H_undef_IOCSIZE_SHIFT
-# undef __SYS_SOCKET_H_undef_IOCSIZE_SHIFT
-# undef IOCSIZE_SHIFT
-#endif
-#ifdef __SYS_SOCKET_H_undef_IOC_IN
-# undef __SYS_SOCKET_H_undef_IOC_IN
-# undef IOC_IN
-#endif
-#ifdef __SYS_SOCKET_H_undef_IOC_INOUT
-# undef __SYS_SOCKET_H_undef_IOC_INOUT
-# undef IOC_INOUT
-#endif
-#ifdef __SYS_SOCKET_H_undef_IOC_OUT
-# undef __SYS_SOCKET_H_undef_IOC_OUT
-# undef IOC_OUT
+#ifdef __USE_MISC
+# include <bits/types/time_t.h>
+# include <asm/socket.h>
+#else
+# define SO_DEBUG 1
+# include <bits/socket-constants.h>
 #endif
 
 /* Structure used to manipulate the SO_LINGER option.  */