Reorganize source code

src/util/util.go

@@ -0,0 +1,56 @@
+package util
+
+// #include <unistd.h>
+import "C"
+
+import (
+	"os"
+	"time"
+)
+
+// Max returns the largest integer
+func Max(first int, items ...int) int {
+	max := first
+	for _, item := range items {
+		if item > max {
+			max = item
+		}
+	}
+	return max
+}
+
+// Max32 returns the largest 32-bit integer
+func Max32(first int32, second int32) int32 {
+	if first > second {
+		return first
+	}
+	return second
+}
+
+// Constrain limits the given integer with the upper and lower bounds
+func Constrain(val int, min int, max int) int {
+	if val < min {
+		return min
+	}
+	if val > max {
+		return max
+	}
+	return val
+}
+
+// DurWithin limits the given time.Duration with the upper and lower bounds
+func DurWithin(
+	val time.Duration, min time.Duration, max time.Duration) time.Duration {
+	if val < min {
+		return min
+	}
+	if val > max {
+		return max
+	}
+	return val
+}
+
+// IsTty returns true is stdin is a terminal
+func IsTty() bool {
+	return int(C.isatty(C.int(os.Stdin.Fd()))) != 0
+}