commit e09e7b1492b2d5c2f68ddf81f8f58e093dd4df6d

Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>

Date:   Mon Dec 13 11:36:42 2021 -0300

    support: Add support_socket_so_timestamp_time64

    Check if the socket support 64-bit network packages timestamps

    (SO_TIMESTAMP and SO_TIMESTAMPNS).  This will be used on recvmsg

    and recvmmsg tests to check if the timestamp should be generated.

    Reviewed-by: Florian Weimer <fweimer@redhat.com>

    (cherry picked from 38bc0f4e78934aab455b31af05cefcbf3c22bece)

diff --git a/support/Makefile b/support/Makefile

index 3c941e1ba9e29aa4..6a5fc9faf2ca2e2d 100644

--- a/support/Makefile

+++ b/support/Makefile

@@ -79,6 +79,7 @@ libsupport-routines = \

   support_set_small_thread_stack_size \

   support_shared_allocate \

   support_small_stack_thread_attribute \

+  support_socket_so_timestamp_time64 \

   support_stat_nanoseconds \

   support_subprocess \

   support_test_compare_blob \

diff --git a/support/support.h b/support/support.h

index 29d56c7c891ee34b..ecfc9a336d272a30 100644

--- a/support/support.h

+++ b/support/support.h

@@ -170,6 +170,10 @@ extern bool support_select_modifies_timeout (void);

    tv_usec larger than 1000000.  */

 extern bool support_select_normalizes_timeout (void);

+/* Return true if socket FD supports 64-bit timestamps with the SOL_SOCKET

+   and SO_TIMESTAMP/SO_TIMESTAMPNS.  */

+extern bool support_socket_so_timestamp_time64 (int fd);

+

 /* Create a timer that trigger after SEC seconds and NSEC nanoseconds.  If

    REPEAT is true the timer will repeat indefinitely.  If CALLBACK is not

    NULL, the function will be called when the timer expires; otherwise a

diff --git a/support/support_socket_so_timestamp_time64.c b/support/support_socket_so_timestamp_time64.c

new file mode 100644

index 0000000000000000..54bf3f42724566f5

--- /dev/null

+++ b/support/support_socket_so_timestamp_time64.c

@@ -0,0 +1,48 @@

+/* Return whether socket supports 64-bit timestamps.

+   Copyright (C) 2022 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 <unistd.h>

+#include <sys/syscall.h>

+#include <sys/socket.h>

+#include <support/support.h>

+#ifdef __linux__

+# include <socket-constants-time64.h>

+#endif

+

+bool

+support_socket_so_timestamp_time64 (int fd)

+{

+#ifdef __linux__

+# if __LINUX_KERNEL_VERSION >= 0x050100                          \

+   || __WORDSIZE == 64                                           \

+   || (defined __SYSCALL_WORDSIZE && __SYSCALL_WORDSIZE == 64)

+  return true;

+# else

+  int level = SOL_SOCKET;

+  int optname = COMPAT_SO_TIMESTAMP_NEW;

+  int optval;

+  socklen_t len = sizeof (optval);

+

+  int r = syscall (__NR_getsockopt, fd, level, optname, &optval, &len;;

+  return r != -1;

+# endif

+#else

+  return false;

+#endif

+}