Module for calculating network address.

ipcalc.erl

-module(ipcalc).
-author('Jon Gretar Borgthorsson <[email protected]>').
-export([
	get_network/2
]).


%% When Netmask is not Integer
get_network(_NetworkAddress, Netmask) when is_list(Netmask) ->
	throw(netmask_not_integer);

%% When Network Address is in format <<192,168,0,1>>.
get_network(NetworkBinary, Netmask) when is_binary(NetworkBinary) ->
	<<Result:Netmask,_/bitstring>> = NetworkBinary,
	Result;

%% When Network Address is in format [192,168,0,1].
get_network([IP1,IP2,IP3,IP4], Netmask) when is_integer(IP1) ->
	get_network(<<IP1:8,IP2:8,IP3:8,IP4:8>>, Netmask);

%% When Network Address is in format ["192","168","0","1"].
get_network([IP1,IP2,IP3,IP4], Netmask) when is_list(IP1) ->
	get_network([
		list_to_integer(IP1),
		list_to_integer(IP2),
		list_to_integer(IP3),
		list_to_integer(IP4)
	], Netmask);

%% When Network Address is in format "192.168.0.1".
get_network(NetworkAddress, Netmask) ->
	IPTokens = string:tokens(NetworkAddress, "."),
	get_network(IPTokens, Netmask).