1 files changed, 40 insertions, 0 deletions
diff --git a/tc/tc_estimator.c b/tc/tc_estimator.c
new file mode 100644
index 0000000..275f254
--- /dev/null
+++ b/tc/tc_estimator.c
@@ -0,0 +1,40 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * tc_core.c		TC core library.
+ *
+ * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <math.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <string.h>
+
+#include "utils.h"
+#include "tc_core.h"
+
+int tc_setup_estimator(unsigned int A, unsigned int time_const, struct tc_estimator *est)
+{
+	for (est->interval = 0; est->interval <= 5; est->interval++) {
+		if (A <= (1<<est->interval)*(TIME_UNITS_PER_SEC/4))
+			break;
+	}
+	if (est->interval > 5)
+		return -1;
+	est->interval -= 2;
+	for (est->ewma_log = 1; est->ewma_log < 32; est->ewma_log++) {
+		double w = 1.0 - 1.0/(1<<est->ewma_log);
+
+		if (A/(-log(w)) > time_const)
+			break;
+	}
+	est->ewma_log--;
+	if (est->ewma_log == 0 || est->ewma_log >= 31)
+		return -1;
+	return 0;
+}