-
Notifications
You must be signed in to change notification settings - Fork 8
/
getaddrinfo.c
86 lines (76 loc) · 1.9 KB
/
getaddrinfo.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
/*exercise getaddrinfo(3) */
#include <netdb.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <sys/types.h>
int main(int argc, char *argv[])
{
int ret = 0;
struct sockaddr *addr = NULL;
struct addrinfo *res = NULL;
struct addrinfo *servinfo = NULL;
char address_str[INET6_ADDRSTRLEN] = {0};
char protocol_str[12] = {0};
char socket_str[12] = {0};
if (argc != 2) {
printf("usage: %s hostname\n", argv[0]);
return EXIT_FAILURE;
}
ret = getaddrinfo(argv[1], NULL, NULL, &servinfo);
if (ret != 0) {
printf("getaddrinfo: %s\n", gai_strerror(ret));
return EXIT_FAILURE;
}
printf("Host %s\n", argv[1]);
for (res = servinfo; res != NULL; res = res->ai_next) {
switch(res->ai_family) {
case AF_INET:
addr = &((struct sockaddr_in *) res->ai_addr)->sin_addr;
break;
case AF_INET6:
addr = &((struct sockaddr_in6 *) res->ai_addr)->sin6_addr;
break;
default:
break;
}
switch(res->ai_socktype) {
case SOCK_STREAM:
strcpy(socket_str, "SOCK_STREAM");
break;
case SOCK_DGRAM:
strcpy(socket_str, "SOCK_DGRAM");
break;
case SOCK_RAW:
strcpy(socket_str, "SOCK_RAW");
break;
default:
sprintf(socket_str, "%d", res->ai_socktype);
break;
}
switch(res->ai_protocol) {
case IPPROTO_TCP:
strcpy(protocol_str, "TCP");
break;
case IPPROTO_UDP:
strcpy(protocol_str, "UDP");
break;
case IPPROTO_IP:
strcpy(protocol_str, "IP");
break;
default:
sprintf(protocol_str, "%d", res->ai_protocol);
break;
}
inet_ntop(res->ai_family, addr, address_str, INET6_ADDRSTRLEN);
printf(" %s (%s %s)\n", address_str, socket_str, protocol_str);
memset(address_str, 0, sizeof(address_str));
memset(socket_str, 0, sizeof(socket_str));
memset(protocol_str, 0, sizeof(protocol_str));
}
freeaddrinfo(servinfo);
return EXIT_SUCCESS;
}