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Diffstat (limited to 'ports/sysdeps/unix/sysv/linux/ia64/has_cpuclock.c')
-rw-r--r--ports/sysdeps/unix/sysv/linux/ia64/has_cpuclock.c51
1 files changed, 51 insertions, 0 deletions
diff --git a/ports/sysdeps/unix/sysv/linux/ia64/has_cpuclock.c b/ports/sysdeps/unix/sysv/linux/ia64/has_cpuclock.c
new file mode 100644
index 0000000000..7889cdbe13
--- /dev/null
+++ b/ports/sysdeps/unix/sysv/linux/ia64/has_cpuclock.c
@@ -0,0 +1,51 @@
+/* Copyright (C) 2000, 2001, 2003, 2004, 2005 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;
+}