From 8903bc9eab959028563f4c4a86b042dea224d484 Mon Sep 17 00:00:00 2001
From: Siddharth Bharat Purohit <siddharthbharatpurohit@gmail.com>
Date: Tue, 21 Jun 2016 16:20:01 +0530
Subject: [PATCH] AP_HAL: add support for get realtime on Darwin systems

---
 libraries/AP_HAL/Util.cpp | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/libraries/AP_HAL/Util.cpp b/libraries/AP_HAL/Util.cpp
index 706e3bacf1..31517e73f2 100644
--- a/libraries/AP_HAL/Util.cpp
+++ b/libraries/AP_HAL/Util.cpp
@@ -2,6 +2,9 @@
 #include "Util.h"
 #include "utility/print_vprintf.h"
 #include <time.h>
+#if defined(__APPLE__) && defined(__MACH__)
+#include <sys/time.h>
+#endif
 
 /* Helper class implements AP_HAL::Print so we can use utility/vprintf */
 class BufferPrinter : public AP_HAL::Print {
@@ -50,9 +53,15 @@ int AP_HAL::Util::vsnprintf(char* str, size_t size, const char *format, va_list
 
 uint64_t AP_HAL::Util::get_system_clock_ms() const
 {
+#if defined(__APPLE__) && defined(__MACH__)
+    struct timeval ts;
+    gettimeofday(&ts, NULL);
+    return ((long long)((ts.tv_sec * 1000) + (ts.tv_usec / 1000)));
+#else
     struct timespec ts;
     clock_gettime(CLOCK_REALTIME, &ts);
     return ((long long)(ts.tv_sec * 1000 + ts.tv_nsec/1000000));
+#endif
 }
 
 void AP_HAL::Util::get_system_clock_utc(int32_t &hour, int32_t &min, int32_t &sec, int32_t &ms) const