X-Git-Url: http://nitlanguage.org

diff --git a/lib/realtime.nit b/lib/realtime.nit
index b66ade0..39c5a27 100644
--- a/lib/realtime.nit
+++ b/lib/realtime.nit
@@ -10,8 +10,8 @@
 # You  are  allowed  to  redistribute it and sell it, alone or is a part of
 # another product.
 
-# Provides the Clock utility class to keep time of real time flow
-module realtime is c_linker_option("-lrt")
+# Services to keep time of the wall clock time
+module realtime is ldflags "-lrt"
 
 in "C header" `{
 #ifdef _POSIX_C_SOURCE
@@ -21,6 +21,28 @@ in "C header" `{
 #include <time.h>
 `}
 
+in "C" `{
+
+#ifdef __MACH__
+/* OS X does not have clock_gettime, mascarade it and use clock_get_time
+ * cf http://stackoverflow.com/questions/11680461/monotonic-clock-on-osx
+*/
+#include <mach/clock.h>
+#include <mach/mach.h>
+#define CLOCK_REALTIME CALENDAR_CLOCK
+#define CLOCK_MONOTONIC SYSTEM_CLOCK
+void clock_gettime(clock_t clock_name, struct timespec *ts) {
+	clock_serv_t cclock;
+	mach_timespec_t mts;
+	host_get_clock_service(mach_host_self(), clock_name, &cclock);
+	clock_get_time(cclock, &mts);
+	mach_port_deallocate(mach_task_self(), cclock);
+	ts->tv_sec = mts.tv_sec;
+	ts->tv_nsec = mts.tv_nsec;
+}
+#endif
+`}
+
 # Elapsed time representation.
 extern class Timespec `{struct timespec*`}
 
@@ -48,32 +70,50 @@ extern class Timespec `{struct timespec*`}
 
 	# Update `self` clock.
 	fun update `{
-		clock_gettime( CLOCK_MONOTONIC, recv );
+		clock_gettime(CLOCK_MONOTONIC, self);
 	`}
 
-	# Substract a Timespec from `self`.
-	fun - ( o : Timespec ) : Timespec
+	# Subtract `other` from `self`
+	fun -(other: Timespec): Timespec
 	do
-		var s = sec - o.sec
-		var ns = nanosec - o.nanosec
-		if ns > nanosec then s += 1
-		return new Timespec( s, ns )
+		var s = sec - other.sec
+		var ns = nanosec - other.nanosec
+		if ns < 0 then
+			s -= 1
+			ns += 1000000000
+		end
+		return new Timespec(s, ns)
 	end
 
 	# Number of whole seconds of elapsed time.
 	fun sec : Int `{
-		return recv->tv_sec;
+		return self->tv_sec;
 	`}
 
 	# Rest of the elapsed time (a fraction of a second).
 	#
 	# Number of nanoseconds.
 	fun nanosec : Int `{
-		return recv->tv_nsec;
+		return self->tv_nsec;
+	`}
+
+	# Elapsed time in microseconds, with both whole seconds and the rest
+	#
+	# May cause an `Int` overflow, use only with a low number of seconds.
+	fun microsec: Int `{
+		return self->tv_sec*1000000 + self->tv_nsec/1000;
+	`}
+
+	# Elapsed time in milliseconds, with both whole seconds and the rest
+	#
+	# May cause an `Int` overflow, use only with a low number of seconds.
+	fun millisec: Int `{
+		return self->tv_sec*1000 + self->tv_nsec/1000000;
 	`}
 
-	# Seconds in Float
-	# Loss of precision but great to print
+	# Number of seconds as a `Float`
+	#
+	# Incurs a loss of precision, but the result is pretty to print.
 	fun to_f: Float do return sec.to_f + nanosec.to_f / 1000000000.0
 
 	redef fun to_s do return "{to_f}s"
@@ -90,7 +130,18 @@ class Clock
 	# Smallest time frame reported by clock
 	fun resolution : Timespec `{
 		struct timespec* tv = malloc( sizeof(struct timespec) );
+#ifdef __MACH__
+		clock_serv_t cclock;
+		int nsecs;
+		mach_msg_type_number_t count;
+		host_get_clock_service(mach_host_self(), SYSTEM_CLOCK, &cclock);
+		clock_get_attributes(cclock, CLOCK_GET_TIME_RES, (clock_attr_t)&nsecs, &count);
+		mach_port_deallocate(mach_task_self(), cclock);
+		tv->tv_sec = 0;
+		tv->tv_nsec = nsecs;
+#else
 		clock_getres( CLOCK_MONOTONIC, tv );
+#endif
 		return tv;
 	`}
 
@@ -108,4 +159,15 @@ class Clock
 		time_at_last_lapse = nt
 		return dt
 	end
+
+	# Seconds since the last call to `lapse`, without resetting the lapse counter
+	fun peek_lapse: Float
+	do
+		var nt = new Timespec.monotonic_now
+		var dt = nt - time_at_last_lapse
+		var r = dt.to_f
+		nt.free
+		dt.free
+		return r
+	end
 end