Refactoring to enable future time scaling, coordinated clocks, etc.

src/xenia/base/clock.h

@@ -0,0 +1,60 @@
+/**
+ ******************************************************************************
+ * Xenia : Xbox 360 Emulator Research Project                                 *
+ ******************************************************************************
+ * Copyright 2015 Ben Vanik. All rights reserved.                             *
+ * Released under the BSD license - see LICENSE in the root for more details. *
+ ******************************************************************************
+ */
+
+#ifndef XENIA_BASE_CLOCK_H_
+#define XENIA_BASE_CLOCK_H_
+
+#include <cstdint>
+
+namespace xe {
+
+class Clock {
+ public:
+  // Host ticks-per-second.
+  static uint64_t host_tick_frequency();
+  // Queries the current host tick count.
+  static uint64_t QueryHostTickCount();
+  // Host time, in FILETIME format.
+  static uint64_t QueryHostSystemTime();
+  // Queries the milliseconds since the host began.
+  static uint32_t QueryHostUptimeMillis();
+
+  // Guest time scalar.
+  static double guest_time_scalar();
+  // Sets the guest time scalar, adjusting tick and wall clock speed.
+  // Ex: 1x=normal, 2x=double speed, 1/2x=half speed.
+  static void set_guest_time_scalar(double scalar);
+  // Guest ticks-per-second.
+  static uint64_t guest_tick_frequency();
+  // Sets the guest ticks-per-second.
+  static void set_guest_tick_frequency(uint64_t frequency);
+  // Time based used for the guest system time.
+  static uint64_t guest_system_time_base();
+  // Sets the guest time base, used for computing the system time.
+  // By default this is the current system time.
+  static void set_guest_system_time_base(uint64_t time_base);
+  // Queries the current guest tick count, accounting for frequency adjustment
+  // and scaling.
+  static uint64_t QueryGuestTickCount();
+  // Queries the guest time, in FILETIME format, accounting for scaling.
+  static uint64_t QueryGuestSystemTime();
+  // Queries the milliseconds since the guest began, accounting for scaling.
+  static uint32_t QueryGuestUptimeMillis();
+
+  // Scales a time duration in milliseconds, from guest time.
+  static uint32_t ScaleGuestDurationMillis(uint32_t guest_ms);
+  // Scales a time duration in 100ns ticks like FILETIME, from guest time.
+  static int64_t ScaleGuestDurationFileTime(int64_t guest_file_time);
+  // Scales a time duration represented as a timeval, from guest time.
+  static void ScaleGuestDurationTimeval(long* tv_sec, long* tv_usec);
+};
+
+}  // namespace xe
+
+#endif  // XENIA_BASE_CLOCK_H_