1 files changed, 51 insertions, 0 deletions
diff --git a/test/unit/app/system_linux_test.cpp b/test/unit/app/system_linux_test.cpp
new file mode 100644
index 0000000..fe89399
--- /dev/null
+++ b/test/unit/app/system_linux_test.cpp
@@ -0,0 +1,51 @@
+#include "app/system.h"
+#include "app/system_linux.h"
+
+#include <gtest/gtest.h>
+
+TEST(SystemLinuxTest, TimeStampDiff)
+{
+    const long long SEC = 1000000000;
+
+    SystemTimeStamp before, after;
+
+    before.clockTime.tv_sec = 1;
+    before.clockTime.tv_nsec = 100;
+
+    after.clockTime.tv_sec = 1;
+    after.clockTime.tv_nsec = 900;
+
+    long long tDiff = TimeStampExactDiff_Linux(&before, &after);
+    EXPECT_EQ( 800, tDiff);
+
+    tDiff = TimeStampExactDiff_Linux(&after, &before);
+    EXPECT_EQ(-800, tDiff);
+
+    // -------
+
+    before.clockTime.tv_sec = 2;
+    before.clockTime.tv_nsec = 200;
+
+    after.clockTime.tv_sec = 3;
+    after.clockTime.tv_nsec = 500;
+
+    tDiff = TimeStampExactDiff_Linux(&before, &after);
+    EXPECT_EQ( SEC + 300, tDiff);
+
+    tDiff = TimeStampExactDiff_Linux(&after, &before);
+    EXPECT_EQ(-SEC - 300, tDiff);
+
+    // -------
+
+    before.clockTime.tv_sec = 3;
+    before.clockTime.tv_nsec = 200;
+
+    after.clockTime.tv_sec = 4;
+    after.clockTime.tv_nsec = 100;
+
+    tDiff = TimeStampExactDiff_Linux(&before, &after);
+    EXPECT_EQ( SEC - 100, tDiff);
+
+    tDiff = TimeStampExactDiff_Linux(&after, &before);
+    EXPECT_EQ(-SEC + 100, tDiff);
+}