add clock_gettime for macos 10.11 and earlier

apps/openssl/Makefile.am

@@ -74,6 +74,12 @@ openssl_SOURCES += compat/poll_win.c
 endif
 endif
 
+if !HAVE_CLOCK_GETTIME
+if HOST_DARWIN
+openssl_SOURCES += compat/clock_gettime_osx.c
+endif
+endif
+
 if !HAVE_STRTONUM
 openssl_SOURCES += compat/strtonum.c
 endif

apps/openssl/compat/clock_gettime_osx.c

@@ -0,0 +1,26 @@
+#include <time.h>
+
+#include <mach/mach_time.h>
+#define ORWL_NANO (+1.0E-9)
+#define ORWL_GIGA UINT64_C(1000000000)
+
+int
+clock_gettime(clock_id_t clock_id, struct timespec *tp)
+{
+	static double orwl_timebase = 0.0;
+	static uint64_t orwl_timestart = 0;
+
+	if (!orwl_timestart) {
+		mach_timebase_info_data_t tb = { 0 };
+		mach_timebase_info(&tb);
+		orwl_timebase = tb.numer;
+		orwl_timebase /= tb.denom;
+		orwl_timestart = mach_absolute_time();
+	}
+
+	double diff = (mach_absolute_time() - orwl_timestart) * orwl_timebase;
+	tp->tv_sec = diff * ORWL_NANO;
+	tp->tv_nsec = diff - (tp->tv_sec * ORWL_GIGA);
+
+	return 0;
+}

include/compat/sys/time.h

@@ -13,10 +13,6 @@ int gettimeofday(struct timeval *tp, void *tzp);
 #include_next <sys/time.h>
 #endif
 
-#ifndef CLOCK_MONOTONIC
-#define CLOCK_MONOTONIC CLOCK_REALTIME
-#endif
-
 #ifndef timersub
 #define timersub(tvp, uvp, vvp)                                         \
 	do {                                                            \

include/compat/time.h

@@ -22,6 +22,19 @@ struct tm *__gmtime_r(const time_t * t, struct tm * tm);
 time_t timegm(struct tm *tm);
 #endif
 
+#ifndef CLOCK_MONOTONIC
+#define CLOCK_MONOTONIC CLOCK_REALTIME
+#endif
+
+#ifndef CLOCK_REALTIME
+#define CLOCK_REALTIME 0
+#endif
+
+#ifndef HAVE_CLOCK_GETTIME
+int
+clock_gettime(clockid_t clock_id, struct timespec *tp);
+#endif
+
 #ifndef timespecsub
 #define timespecsub(tsp, usp, vsp)                                      \
         do {                                                            \

m4/check-libc.m4

@@ -131,6 +131,8 @@ AC_SEARCH_LIBS([clock_gettime],[rt posix4])
 AC_CHECK_FUNC([clock_gettime])
 AC_SEARCH_LIBS([dl_iterate_phdr],[dl])
 AC_CHECK_FUNC([dl_iterate_phdr])
+
+AM_CONDITIONAL([HAVE_CLOCK_GETTIME], [test "x$ac_cv_func_clock_gettime" = xyes])
 ])
 
 AC_DEFUN([CHECK_VA_COPY], [