1 | /* Example of Local-Namespace Sockets |
2 | Copyright (C) 1991-2022 Free Software Foundation, Inc. |
3 | |
4 | This program is free software; you can redistribute it and/or |
5 | modify it under the terms of the GNU General Public License |
6 | as published by the Free Software Foundation; either version 2 |
7 | of the License, or (at your option) any later version. |
8 | |
9 | This program is distributed in the hope that it will be useful, |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
12 | GNU General Public License for more details. |
13 | |
14 | You should have received a copy of the GNU General Public License |
15 | along with this program; if not, see <https://www.gnu.org/licenses/>. |
16 | */ |
17 | |
18 | #include <stddef.h> |
19 | #include <stdio.h> |
20 | #include <errno.h> |
21 | #include <stdlib.h> |
22 | #include <string.h> |
23 | #include <sys/socket.h> |
24 | #include <sys/un.h> |
25 | |
26 | int |
27 | make_named_socket (const char *filename) |
28 | { |
29 | struct sockaddr_un name; |
30 | int sock; |
31 | size_t size; |
32 | |
33 | /* Create the socket. */ |
34 | sock = socket (PF_LOCAL, SOCK_DGRAM, protocol: 0); |
35 | if (sock < 0) |
36 | { |
37 | perror ("socket" ); |
38 | exit (EXIT_FAILURE); |
39 | } |
40 | |
41 | /* Bind a name to the socket. */ |
42 | name.sun_family = AF_LOCAL; |
43 | strncpy (name.sun_path, filename, sizeof (name.sun_path)); |
44 | name.sun_path[sizeof (name.sun_path) - 1] = '\0'; |
45 | |
46 | /* The size of the address is |
47 | the offset of the start of the filename, |
48 | plus its length (not including the terminating null byte). |
49 | Alternatively you can just do: |
50 | size = SUN_LEN (&name); |
51 | */ |
52 | size = (offsetof (struct sockaddr_un, sun_path) |
53 | + strlen (name.sun_path)); |
54 | |
55 | if (bind (fd: sock, addr: (struct sockaddr *) &name, len: size) < 0) |
56 | { |
57 | perror ("bind" ); |
58 | exit (EXIT_FAILURE); |
59 | } |
60 | |
61 | return sock; |
62 | } |
63 | |