1/* Return whether socket supports 64-bit timestamps.
2 Copyright (C) 2022 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#include <errno.h>
20#include <unistd.h>
21#include <sys/syscall.h>
22#include <sys/socket.h>
23#include <support/support.h>
24#ifdef __linux__
25# include <socket-constants-time64.h>
26#endif
27
28bool
29support_socket_so_timestamp_time64 (int fd)
30{
31#ifdef __linux__
32# if __LINUX_KERNEL_VERSION >= 0x050100 \
33 || __WORDSIZE == 64 \
34 || (defined __SYSCALL_WORDSIZE && __SYSCALL_WORDSIZE == 64)
35 return true;
36# else
37 int level = SOL_SOCKET;
38 int optname = COMPAT_SO_TIMESTAMP_NEW;
39 int optval;
40 socklen_t len = sizeof (optval);
41
42 int r = syscall (__NR_getsockopt, fd, level, optname, &optval, &len);
43 return r != -1;
44# endif
45#else
46 return false;
47#endif
48}
49