1 files changed, 99 insertions, 0 deletions
diff --git a/libs/backends/portaudio/win_utils.cc b/libs/backends/portaudio/win_utils.cc
new file mode 100644
index 0000000000..7bda04ccf1
--- /dev/null
+++ b/libs/backends/portaudio/win_utils.cc
@@ -0,0 +1,99 @@
+/*
+ * Copyright (C) 2015 Tim Mayberry <mojofunk@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "win_utils.h"
+
+#include <windows.h>
+
+#include "pbd/compose.h"
+
+#include "debug.h"
+
+namespace {
+
+LARGE_INTEGER
+get_frequency ()
+{
+	LARGE_INTEGER freq;
+	QueryPerformanceFrequency(&freq);
+	return freq;
+}
+
+
+UINT&
+old_timer_resolution ()
+{
+	static UINT timer_res_ms = 0;
+	return timer_res_ms;
+}
+
+} // anon namespace
+
+namespace utils {
+
+bool
+set_min_timer_resolution ()
+{
+	TIMECAPS caps;
+
+	if (timeGetDevCaps (&caps, sizeof(TIMECAPS)) != TIMERR_NOERROR) {
+		DEBUG_TIMING ("Could not get timer device capabilities.\n");
+		return false;
+	} else {
+		old_timer_resolution () = caps.wPeriodMin;
+		if (timeBeginPeriod (caps.wPeriodMin) != TIMERR_NOERROR) {
+			DEBUG_TIMING (string_compose (
+			    "Could not set minimum timer resolution to %1(ms)\n", caps.wPeriodMin));
+			return false;
+		}
+	}
+
+	DEBUG_TIMING (string_compose ("Multimedia timer resolution set to %1(ms)\n",
+	                              caps.wPeriodMin));
+
+	return true;
+}
+
+bool
+reset_timer_resolution ()
+{
+	if (old_timer_resolution ()) {
+		if (timeEndPeriod (old_timer_resolution ()) != TIMERR_NOERROR) {
+			DEBUG_TIMING ("Could not reset timer resolution.\n");
+			return false;
+		}
+	}
+
+	DEBUG_TIMING (string_compose ("Multimedia timer resolution set to %1(ms)\n",
+	                              old_timer_resolution ()));
+
+	return true;
+}
+
+uint64_t get_microseconds ()
+{
+	static LARGE_INTEGER frequency = get_frequency ();
+	LARGE_INTEGER current_val;
+
+	QueryPerformanceCounter (&current_val);
+
+	return (uint64_t)(((double)current_val.QuadPart) /
+	                  ((double)frequency.QuadPart) * 1000000.0);
+}
+
+} // namespace utils