added some dhcp4 packet functions and generic byte reading functions

sock_test.go

@@ -0,0 +1,34 @@
+package haza_test
+
+//import "fmt"
+import "haza"
+import "net"
+import "testing"
+
+func TestDhcp4Conn(t *testing.T) {
+	var c *haza.Dhcp4Conn
+	var addr *net.UDPAddr
+	var err error
+
+	addr, err = net.ResolveUDPAddr("udp6", "[::1]:1158")
+	if err != nil {
+		t.Errorf("failed to resolve address - %s\n", err.Error())
+	} else {
+		c, err = haza.NewDhcp4Conn("", addr)
+		if err == nil {
+			t.Errorf("this must fail as v6 address is given to v4 conn - %v\n", addr)
+		}
+	}
+
+	addr, err = net.ResolveUDPAddr("udp4", "127.0.0.1:1158")
+	if err != nil {
+		t.Errorf("failed to resolve address - %s\n", err.Error())
+	} else {
+		c, err = haza.NewDhcp4Conn("", addr)
+		if err != nil {
+			t.Errorf("failed to create dhcp4 conn - %s\n", err.Error())
+		} else {
+			c.Close()
+		}
+	}
+}