From e98919cf3c6e8c7e33a182da8efdd984bce6d655 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Beat=20K=C3=BCng?= <beat-kueng@gmx.net>
Date: Fri, 13 Apr 2018 10:21:05 +0200
Subject: [PATCH] drv_hrt: add user-defined integer literals for time constants

The goal is to improve the readability for expressions like:
if (hrt_elapsed_time(&start_time) > 8000000)

Available since C++11
---
 src/drivers/drv_hrt.h | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/src/drivers/drv_hrt.h b/src/drivers/drv_hrt.h
index 61bb5dfe1e..ac0694aba9 100644
--- a/src/drivers/drv_hrt.h
+++ b/src/drivers/drv_hrt.h
@@ -194,3 +194,33 @@ __EXPORT extern void	hrt_stop_delay_delta(hrt_abstime delta);
 #endif
 
 __END_DECLS
+
+
+
+#ifdef	__cplusplus
+
+namespace time_literals
+{
+
+// User-defined integer literals for different time units.
+// The base unit is hrt_abstime in microseconds
+
+constexpr hrt_abstime operator "" _s(unsigned long long seconds)
+{
+	return hrt_abstime(seconds * 1000000ULL);
+}
+
+constexpr hrt_abstime operator "" _ms(unsigned long long seconds)
+{
+	return hrt_abstime(seconds * 1000ULL);
+}
+
+constexpr hrt_abstime operator "" _us(unsigned long long seconds)
+{
+	return hrt_abstime(seconds);
+}
+
+} /* namespace time_literals */
+
+
+#endif /* __cplusplus */