1 files changed, 48 insertions, 0 deletions
diff --git a/timer.c b/timer.c
new file mode 100644
index 0000000..e437397
--- /dev/null
+++ b/timer.c
@@ -0,0 +1,48 @@
+#include "timer.h"
+
+#include <time.h>
+
+#if defined(_WIN32)
+#include <windows.h>
+int64_t frequency;
+#endif
+
+void TimerInit()
+{
+#if defined(_WIN32)
+    QueryPerformanceFrequency((LARGE_INTEGER *) &frequency);
+#endif
+}
+
+int64_t TimerGetTimeMicro()
+{
+#if defined(_WIN32)
+    int64_t value;
+    QueryPerformanceCounter((LARGE_INTEGER *) &value);
+    value = value * 1000LL*1000LL;
+    return value / frequency;
+#else
+    struct timespec tp;
+    if (clock_gettime(CLOCK_MONOTONIC, &tp))
+    {
+        return 0;
+    }
+    return (((int64_t) tp.tv_sec) * 1000LL*1000LL*1000LL + ((int64_t) tp.tv_nsec)) / 1000LL;
+#endif
+}
+
+void TimerStart(Timer *timer)
+{
+    *timer = TimerGetTimeMicro();
+}
+
+int64_t TimerElapsedMicro(Timer *timer)
+{
+    int64_t now = TimerGetTimeMicro(timer);
+    return now - *timer;
+}
+
+int64_t TimerElapsedMilli(Timer *timer)
+{
+    return TimerElapsedMicro(timer) / 1000LL;
+}