1 files changed, 76 insertions, 0 deletions
diff --git a/support/support_path_support_time64.c b/support/support_path_support_time64.c
new file mode 100644
index 0000000..74af7d4
--- /dev/null
+++ b/support/support_path_support_time64.c
@@ -0,0 +1,76 @@
+/* Check if path supports 64-bit time interfaces.
+   Copyright (C) 2021 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 <fcntl.h>
+#include <support/check.h>
+#include <support/support.h>
+#include <sys/stat.h>
+#ifdef __linux__
+#include <sysdep.h>
+#endif
+
+#ifdef __linux__
+static int
+utimesat_call (const char *path, const struct __timespec64 tsp[2])
+{
+# ifndef __NR_utimensat_time64
+#  define __NR_utimensat_time64 __NR_utimensat
+# endif
+  return INLINE_SYSCALL_CALL (utimensat_time64, AT_FDCWD, path, &tsp[0], 0);
+}
+#endif
+
+bool
+support_path_support_time64 (const char *path)
+{
+#ifdef __linux__
+  /* Obtain the original timestamps to restore at the end.  */
+  struct statx ostx;
+  TEST_VERIFY_EXIT (statx (AT_FDCWD, path, 0, STATX_BASIC_STATS, &ostx) == 0);
+
+  const struct __timespec64 tsp[] =
+  {
+    /* 1s and 2s after y2038 limit.  */
+    { 0x80000001ULL, 0 },
+    { 0x80000002ULL, 0 }
+  };
+  /* Return is kernel does not support __NR_utimensat_time64.  */
+  if (utimesat_call (path, tsp) == -1)
+    return false;
+
+  /* Verify if the last access and last modification time match the ones
+     obtained with statx.  */
+  struct statx stx;
+  TEST_VERIFY_EXIT (statx (AT_FDCWD, path, 0, STATX_BASIC_STATS, &stx) == 0);
+
+  bool support = stx.stx_atime.tv_sec == tsp[0].tv_sec
+		 && stx.stx_mtime.tv_sec == tsp[1].tv_sec;
+
+  /* Reset to original timestamps.  */
+  const struct __timespec64 otsp[] =
+  {
+    { ostx.stx_atime.tv_sec, ostx.stx_atime.tv_nsec },
+    { ostx.stx_mtime.tv_sec, ostx.stx_mtime.tv_nsec },
+  };
+  TEST_VERIFY_EXIT (utimesat_call (path, otsp) == 0);
+
+  return support;
+#else
+  return true;
+#endif
+}