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-rw-r--r--REORG.TODO/sysdeps/unix/sysv/linux/ia64/has_cpuclock.c51
1 files changed, 51 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/ia64/has_cpuclock.c b/REORG.TODO/sysdeps/unix/sysv/linux/ia64/has_cpuclock.c
new file mode 100644
index 0000000000..2207c88c47
--- /dev/null
+++ b/REORG.TODO/sysdeps/unix/sysv/linux/ia64/has_cpuclock.c
@@ -0,0 +1,51 @@
+/* Copyright (C) 2000-2017 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/>.  */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <not-cancel.h>
+
+static int itc_usable;
+
+static int
+has_cpuclock (void)
+{
+  if (__builtin_expect (itc_usable == 0, 0))
+    {
+      int newval = 1;
+      int fd = open_not_cancel_2 ("/proc/sal/itc_drift", O_RDONLY);
+      if (__builtin_expect (fd != -1, 1))
+	{
+	  char buf[16];
+	  /* We expect the file to contain a single digit followed by
+	     a newline.  If the format changes we better not rely on
+	     the file content.  */
+	  if (read_not_cancel (fd, buf, sizeof buf) != 2
+	      || buf[0] != '0' || buf[1] != '\n')
+	    newval = -1;
+
+	  close_not_cancel_no_status (fd);
+	}
+
+      itc_usable = newval;
+    }
+
+  return itc_usable;
+}