Begin libsandglass implementation.

1 files changed, 39 insertions, 0 deletions

diff --git a/src/tsc.c b/src/tsc.c
new file mode 100644
index 0000000..64fe1b1
--- /dev/null
+++ b/src/tsc.c
@@ -0,0 +1,39 @@
+/*************************************************************************
+ * Copyright (C) 2008 Tavian Barnes <tavianator@gmail.com>               *
+ *                                                                       *
+ * This file is part of The Sandglass Library.                           *
+ *                                                                       *
+ * The Sandglass 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  *
+ * 3 of the License, or (at your option) any later version.              *
+ *                                                                       *
+ * The Sandglass 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 this program.  If not, see                         *
+ * <http://www.gnu.org/licenses/>.                                       *
+ *************************************************************************/
+
+#include "sandglass_impl.h"
+#include "sandglass.h"
+#include <time.h>
+
+/* Gets the number of clock ticks per second */
+double
+sandglass_tsc_resolution()
+{
+  static long tsc = 0;
+  struct timespec ts = { .tv_sec = 0, .tv_nsec = 100000000 };
+
+  if (tsc == 0) {
+    tsc = sandglass_get_tsc();
+    while (nanosleep(&ts, &ts) != 0);
+    tsc = sandglass_get_tsc() - tsc;
+  }
+
+  return tsc*10.0;
+}