aquatic_http: work on glommio network implementation

aquatic_http/src/lib/common/mod.rs

@@ -0,0 +1,31 @@
+pub fn num_digits_in_usize(mut number: usize) -> usize {
+    let mut num_digits = 1usize;
+
+    while number >= 10 {
+        num_digits += 1;
+
+        number /= 10;
+    }
+
+    num_digits
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_num_digits_in_usize() {
+        let f = num_digits_in_usize;
+
+        assert_eq!(f(0), 1);
+        assert_eq!(f(1), 1);
+        assert_eq!(f(9), 1);
+        assert_eq!(f(10), 2);
+        assert_eq!(f(11), 2);
+        assert_eq!(f(99), 2);
+        assert_eq!(f(100), 3);
+        assert_eq!(f(101), 3);
+        assert_eq!(f(1000), 4);
+    }
+}