Add timers for measuring elapsed time

src/Platform/Posix/Timer.c

@@ -0,0 +1,139 @@
+#include <BH/Timer.h>
+
+#include <stdlib.h>
+#include <sys/time.h>
+#include <time.h>
+#include <unistd.h>
+
+
+#define TYPE_OLD_REALTIME   0x0000
+#define TYPE_NEW_REALTIME   0x0001
+#define TYPE_MONOTONIC      0x0002
+
+
+struct BH_Timer
+{
+    int type;
+    int64_t sec;
+    int64_t nsec;
+};
+
+
+static int checkAvailableTimer(void)
+{
+#if (_POSIX_TIMERS > 0) || defined(BH_USE_CLOCK_GETTIME)
+    struct timespec ts;
+
+    if (!clock_gettime(CLOCK_MONOTONIC, &ts))
+        return TYPE_MONOTONIC;
+
+    if (!clock_gettime(CLOCK_REALTIME, &ts))
+        return TYPE_NEW_REALTIME;
+#endif
+
+    return TYPE_OLD_REALTIME;
+}
+
+
+static void getTimer(int type,
+                     int64_t *sec,
+                     int64_t *nsec)
+{
+    struct timespec ts;
+    struct timeval tv;
+
+    switch (type)
+    {
+#if (_POSIX_TIMERS > 0) || defined(BH_USE_CLOCK_GETTIME)
+    case TYPE_MONOTONIC:
+        clock_gettime(CLOCK_MONOTONIC, &ts);
+        *sec = ts.tv_sec;
+        *nsec = ts.tv_nsec;
+        break;
+
+    case TYPE_NEW_REALTIME:
+        clock_gettime(CLOCK_REALTIME, &ts);
+        *sec = ts.tv_sec;
+        *nsec = ts.tv_nsec;
+        break;
+#endif
+
+    default:
+    case TYPE_OLD_REALTIME:
+        gettimeofday(&tv, NULL);
+        *sec = tv.tv_sec;
+        *nsec = tv.tv_usec * (uint64_t)1000;
+        break;
+    }
+}
+
+
+BH_Timer *BH_TimerNew(void)
+{
+    BH_Timer *result;
+
+    result = malloc(sizeof(*result));
+    if (result)
+    {
+        result->type = checkAvailableTimer();
+        BH_TimerStart(result);
+    }
+
+    return result;
+}
+
+
+void BH_TimerFree(BH_Timer *timer)
+{
+    free(timer);
+}
+
+
+int BH_TimerIsMonotonic(BH_Timer *timer)
+{
+    return timer->type == TYPE_MONOTONIC;
+}
+
+
+void BH_TimerStart(BH_Timer *timer)
+{
+    getTimer(timer->type, &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->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, &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, &newSec, &newNsec);
+    newSec -= timer->sec;
+    newNsec -= timer->nsec;
+
+    return (newSec * 1000000000) + newNsec;
+}