fstests: add ChunkedUploadConfig

fstest/fstests/bits.go

@@ -0,0 +1,33 @@
+//+build !go1.9
+
+package fstests
+
+func leadingZeros64(x uint64) int {
+	var n uint64 = 64
+
+	if y := x >> 32; y != 0 {
+		n = n - 32
+		x = y
+	}
+	if y := x >> 16; y != 0 {
+		n = n - 16
+		x = y
+	}
+	if y := x >> 8; y != 0 {
+		n = n - 8
+		x = y
+	}
+	if y := x >> 4; y != 0 {
+		n = n - 4
+		x = y
+	}
+	if y := x >> 2; y != 0 {
+		n = n - 2
+		x = y
+	}
+	if y := x >> 1; y != 0 {
+		return int(n - 2)
+	}
+
+	return int(n - x)
+}