1 files changed, 51 insertions, 0 deletions
diff --git a/ip.pl b/ip.pl
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+++ b/ip.pl
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+% vim: syntax=prolog
+
+:- use_module(library(clpfd)).
+:- use_module(library(dcg/basics)).
+
+ip4(A, B, C, D, Addr) :- 
+  A in 0..255,
+  B in 0..255,
+  C in 0..255,
+  D in 0..255,
+  Addr #= (A * 2^24 + B * 2^16 + C * 2^8 + D).
+
+ip4_range(ip4(_, _, _, _), Range) :- 
+  Range in 0..32.
+
+ip_format(ip4(A, B, C, D, _), Str) :-
+  format(string(Str), "~w.~w.~w.~w", [A, B, C, D]).
+
+ip_format(ip4_range(ip4(A, B, C, D, _), Range), Str) :-
+  format(string(Str), "~w.~w.~w.~w/~w", [A, B, C, D, Range]).
+
+ip4_g(A, B, C, D) --> ip4_num(A), ".", ip4_num(B), ".", ip4_num(C), ".", ip4_num(D).
+ip4_num(D) --> integer(D), { D >= 0, D =< 255 }.
+ipx(A) --> integer(A).
+
+ip_parse(Str, Obj) :-
+  string_codes(Str, Codes),
+  phrase(ip4_g(A, B, C, D), Codes),
+  Obj = ip4(A, B, C, D).
+
+:- begin_tests(lists).
+:- use_module(library(lists)).
+
+test(ip4) :-
+  ip4(127, 0, 0, 1, A),
+  assertion(A =:= (127 * 2**24 + 1)).
+
+test(ip_format) :-
+  ip_format(ip4(127, 0, 0, 1, _), Str),
+  assertion(Str == "127.0.0.1").
+
+test(ip_format) :-
+  Ip = ip4_range(ip4(192, 168, 0, 0, _), 24),
+  ip_format(Ip, Str),
+  assertion(Str == "192.168.0.0/24").
+
+test(ip_parse) :-
+  ip_parse("1.2.3.4", Ip),
+  assertion(Ip == ip4(1, 2, 3, 4)).
+
+:- end_tests(lists).