1 files changed, 130 insertions, 0 deletions
diff --git a/src/Platform/Win32/Timer.c b/src/Platform/Win32/Timer.c
new file mode 100644
index 0000000..03d4d7f
--- /dev/null
+++ b/src/Platform/Win32/Timer.c
@@ -0,0 +1,130 @@
+#include <BH/Timer.h>
+
+#include <stdlib.h>
+#include <windows.h>
+
+
+#define TYPE_TICKS   0x0000
+#define TYPE_COUNTER 0x0001
+
+
+struct BH_Timer
+{
+    int type;
+    LARGE_INTEGER frequency;
+    int64_t sec;
+    int64_t nsec;
+};
+
+
+static int checkAvailableTimer(LARGE_INTEGER *frequency)
+{
+    LARGE_INTEGER dummy;
+
+    if (QueryPerformanceFrequency(frequency))
+    {
+        if (QueryPerformanceCounter(&dummy))
+        {
+            return TYPE_COUNTER;
+        }
+    }
+
+    return TYPE_TICKS;
+}
+
+
+static void getTimer(int type,
+                     LARGE_INTEGER *frequency,
+                     int64_t *sec,
+                     int64_t *nsec)
+{
+    LARGE_INTEGER newCount;
+    int64_t newTicks;
+
+    switch (type)
+    {
+    case TYPE_COUNTER:
+        QueryPerformanceCounter(&newCount);
+        *sec = newCount.QuadPart / frequency->QuadPart;
+        *nsec = (newCount.QuadPart - *sec * frequency->QuadPart) * 1000000000 / frequency->QuadPart;
+        break;
+
+    default:
+    case TYPE_TICKS:
+        newTicks = GetTickCount64();
+        *sec = newTicks / 1000;
+        *nsec = (newTicks - *sec * 1000) * 1000000;
+        break;
+    }
+}
+
+
+BH_Timer *BH_TimerNew(void)
+{
+    BH_Timer *result;
+
+    result = malloc(sizeof(*result));
+    if (result)
+    {
+        result->type = checkAvailableTimer(&result->frequency);
+        BH_TimerStart(result);
+    }
+
+    return result;
+}
+
+
+void BH_TimerFree(BH_Timer *timer)
+{
+    free(timer);
+}
+
+
+int BH_TimerIsMonotonic(BH_Timer *timer)
+{
+    return timer->type == TYPE_COUNTER;
+}
+
+
+void BH_TimerStart(BH_Timer *timer)
+{
+    getTimer(timer->type, &timer->frequency, &timer->sec, &timer->nsec);
+}
+
+
+int64_t BH_TimerRestart(BH_Timer *timer)
+{
+    int64_t oldSec, oldNsec;
+
+    oldSec = timer->sec; oldNsec = timer->nsec;
+
+    getTimer(timer->type, &timer->frequency, &timer->sec, &timer->nsec);
+    oldSec = timer->sec - oldSec;
+    oldNsec = timer->nsec - oldNsec;
+
+    return (oldSec * 1000) + (oldNsec / 1000000);
+}
+
+
+int64_t BH_TimerMilliseconds(BH_Timer *timer)
+{
+    int64_t newSec, newNsec;
+
+    getTimer(timer->type, &timer->frequency, &newSec, &newNsec);
+    newSec -= timer->sec;
+    newNsec -= timer->nsec;
+
+    return (newSec * 1000) + (newNsec / 1000000);
+}
+
+
+int64_t BH_TimerNanoseconds(BH_Timer *timer)
+{
+    int64_t newSec, newNsec;
+
+    getTimer(timer->type, &timer->frequency, &newSec, &newNsec);
+    newSec -= timer->sec;
+    newNsec -= timer->nsec;
+
+    return (newSec * 1000000000) + newNsec;
+}