test: add chrono.

test/chrono.h

@@ -0,0 +1,75 @@
+/*
+ * Copyright 2017 Leonid Yuriev <leo@yuriev.ru>
+ * and other libmdbx authors: please see AUTHORS file.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted only as authorized by the OpenLDAP
+ * Public License.
+ *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
+ */
+
+#pragma once
+
+#include "base.h"
+#include "log.h"
+#include "utils.h"
+
+namespace chrono {
+
+typedef union time {
+  uint64_t fixedpoint;
+  struct __packed {
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+    uint32_t fractional;
+    uint32_t utc;
+#else
+    uint32_t utc;
+    uint32_t fractional;
+#endif
+  };
+} time;
+
+uint32_t ns2fractional(uint32_t);
+uint32_t fractional2ns(uint32_t);
+uint32_t us2fractional(uint32_t);
+uint32_t fractional2us(uint32_t);
+uint32_t ms2fractional(uint32_t);
+uint32_t fractional2ms(uint32_t);
+
+time from_ns(uint64_t us);
+time from_us(uint64_t ns);
+time from_ms(uint64_t ms);
+
+inline time from_utc(time_t utc) {
+  assert(utc < UINT32_MAX);
+  time result;
+  result.fixedpoint = ((uint64_t)utc) << 32;
+  return result;
+}
+
+#if defined(HAVE_TIMESPEC_TV_NSEC) || defined(__timespec_defined) ||           \
+    defined(CLOCK_REALTIME)
+inline time from_timespec(const struct timespec &ts) {
+  time result;
+  result.fixedpoint =
+      ((uint64_t)ts.tv_sec << 32) | ns2fractional((uint32_t)ts.tv_nsec);
+  return result;
+}
+#endif /* HAVE_TIMESPEC_TV_NSEC */
+
+#if defined(HAVE_TIMEVAL_TV_USEC) || defined(_STRUCT_TIMEVAL)
+inline time from_timeval(const struct timeval &tv) {
+  time result;
+  result.fixedpoint =
+      ((uint64_t)tv.tv_sec << 32) | us2fractional((uint32_t)tv.tv_usec);
+  return result;
+}
+#endif /* HAVE_TIMEVAL_TV_USEC */
+
+time now();
+
+} /* namespace chrono */