1 /*
2  * Copyright 2021 Google LLC
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include <arpa/inet.h>
18 #include <netinet/in.h>
19 #include <stdio.h>
20 #include <sys/socket.h>
21 
22 int main(int argc, char* argv[])
23 {
24     if (argc < 1)
25     {
26         return 1;
27     }
28     if (argc != 2)
29     {
30         fprintf(stderr, "Usage: %s <ip address>\n", argv[0]);
31         return 1;
32     }
33 
34     union
35     {
36         struct in_addr in;
37         struct in6_addr in6;
38     } buf;
39     int af = AF_INET6;
40     if (inet_pton(af, argv[1], &buf) != 1)
41     {
42         af = AF_INET;
43         if (inet_pton(af, argv[1], &buf) != 1)
44         {
45             fprintf(stderr, "Invalid IP Address: %s\n", argv[1]);
46             return 2;
47         }
48     }
49 
50     char str[INET6_ADDRSTRLEN];
51     if (inet_ntop(af, &buf, str, sizeof(str)) == NULL)
52     {
53         return 1;
54     }
55 
56     printf("%s\n", str);
57     return 0;
58 }
59