1 files changed, 92 insertions, 0 deletions
diff --git a/src/clocks.h b/src/clocks.h
new file mode 100644
index 000000000..c1b8e7017
--- /dev/null
+++ b/src/clocks.h
@@ -0,0 +1,92 @@
+#ifndef NETDATA_CLOCKS_H
+#define NETDATA_CLOCKS_H 1
+
+#ifndef HAVE_STRUCT_TIMESPEC
+struct timespec {
+    time_t tv_sec;  /* seconds */
+    long   tv_nsec; /* nanoseconds */
+};
+#endif
+
+#ifndef HAVE_CLOCKID_T
+typedef int clockid_t;
+#endif
+
+#ifndef HAVE_CLOCK_GETTIME
+int clock_gettime(clockid_t clk_id, struct timespec *ts);
+#endif
+
+/* Linux value is as good as any other */
+#ifndef CLOCK_REALTIME
+#define CLOCK_REALTIME  0
+#endif
+
+#ifndef CLOCK_MONOTONIC
+/* fallback to CLOCK_REALTIME if not available */
+#define CLOCK_MONOTONIC CLOCK_REALTIME
+#endif
+
+#ifndef CLOCK_BOOTTIME
+/* fallback to CLOCK_MONOTONIC if not available */
+#define CLOCK_BOOTTIME  CLOCK_MONOTONIC
+#else
+#ifdef HAVE_CLOCK_GETTIME
+#define CLOCK_BOOTTIME_IS_AVAILABLE 1 // required for /proc/uptime
+#endif
+#endif
+
+typedef unsigned long long usec_t;
+
+#define NSEC_PER_SEC    1000000000ULL
+#define NSEC_PER_MSEC   1000000ULL
+#define NSEC_PER_USEC   1000ULL
+#define USEC_PER_SEC    1000000ULL
+
+#ifndef HAVE_CLOCK_GETTIME
+/* Fallback function for POSIX.1-2001 clock_gettime() function.
+ *
+ * We use a realtime clock from gettimeofday(), this will
+ * make systems without clock_gettime() support sensitive
+ * to time jumps or hibernation/suspend side effects.
+ */
+extern int clock_gettime(clockid_t clk_id, struct timespec *ts);
+#endif
+
+/* Fills struct timeval with time since EPOCH from real-time clock (i.e. wall-clock).
+ * - Hibernation/suspend time is included
+ * - adjtime()/NTP adjustments affect this clock
+ * Return 0 on succes, -1 else with errno set appropriately.
+ */
+extern int now_realtime_timeval(struct timeval *tv);
+
+/* Returns time since EPOCH from real-time clock (i.e. wall-clock).
+ * - Hibernation/suspend time is included
+ * - adjtime()/NTP adjustments affect this clock
+ */
+extern time_t now_realtime_sec(void);
+extern usec_t now_realtime_usec(void);
+
+/* Returns time from monotonic clock if available, real-time clock else.
+ * If monotonic clock is available:
+ * - hibernation/suspend time is not included
+ * - adjtime()/NTP adjusments affect this clock
+ * If monotonic clock is not available, this fallbacks to now_realtime().
+ */
+extern time_t now_monotonic_sec(void);
+extern usec_t now_monotonic_usec(void);
+
+/* Returns time from boottime clock if available,
+ * monotonic clock else if available, real-time clock else.
+ * If boottime clock is available:
+ * - hibernation/suspend time is included
+ * - adjtime()/NTP adjusments affect this clock
+ * If boottime clock is not available, this fallbacks to now_monotonic().
+ * If monotonic clock is not available, this fallbacks to now_realtime().
+ */
+extern time_t now_boottime_sec(void);
+extern usec_t now_boottime_usec(void);
+
+extern usec_t timeval_usec(struct timeval *ts);
+extern usec_t dt_usec(struct timeval *now, struct timeval *old);
+
+#endif /* NETDATA_CLOCKS_H */