From 7459f287e039f44bbf6b8b1cab4e296401d67202 Mon Sep 17 00:00:00 2001
From: winlin <winlin@vip.126.com>
Date: Thu, 17 Sep 2020 12:52:16 +0800
Subject: [PATCH] System: Add srs duration api

---
 trunk/src/core/srs_core_time.cpp | 9 +++++++++
 trunk/src/core/srs_core_time.hpp | 3 +++
 2 files changed, 12 insertions(+)

diff --git a/trunk/src/core/srs_core_time.cpp b/trunk/src/core/srs_core_time.cpp
index 86d360975..b977a3c4a 100644
--- a/trunk/src/core/srs_core_time.cpp
+++ b/trunk/src/core/srs_core_time.cpp
@@ -23,3 +23,12 @@
 
 #include <srs_core_time.hpp>
 
+srs_utime_t srs_duration(srs_utime_t start, srs_utime_t end)
+{
+    if (start == 0 || end == 0) {
+        return 0;
+    }
+
+    return end - start;
+}
+
diff --git a/trunk/src/core/srs_core_time.hpp b/trunk/src/core/srs_core_time.hpp
index 1d0799d42..df33ef623 100644
--- a/trunk/src/core/srs_core_time.hpp
+++ b/trunk/src/core/srs_core_time.hpp
@@ -36,6 +36,9 @@ typedef int64_t srs_utime_t;
 #define srsu2ms(us) ((us) / SRS_UTIME_MILLISECONDS)
 #define srsu2msi(us) int((us) / SRS_UTIME_MILLISECONDS)
 
+// Them time duration = end - start. return 0, if start or end is 0.
+srs_utime_t srs_duration(srs_utime_t start, srs_utime_t end);
+
 // The time unit in ms, for example 120 * SRS_UTIME_SECONDS means 120s.
 #define SRS_UTIME_SECONDS 1000000LL