1 /*
2 * Copyright 2010, Atis Elsts, the.kfx@gmail.com
3 * Distributed under the terms of the MIT license.
4 */
5
6
7 #include <unistd.h>
8 #include <memory.h>
9 #include <netinet/in.h>
10 #include <arpa/inet.h>
11 #include <errno.h>
12 #include <stdio.h>
13 #include <stdlib.h>
14
15
16 const unsigned short TEST_PORT = 40000;
17
18
19 int
main(int argc,char * argv[])20 main(int argc, char *argv[])
21 {
22 int socketFamily = AF_INET;
23
24 int i = 1;
25 if (argc > i) {
26 if (!strcmp(argv[i], "-4")) {
27 i++;
28 socketFamily = AF_INET;
29 } else if (!strcmp(argv[i], "-6")) {
30 i++;
31 socketFamily = AF_INET6;
32 }
33 }
34 in_addr multicastSource;
35 multicastSource.s_addr = 0;
36 if (argc > i) {
37 if (!strcmp(argv[i], "-s")) {
38 ++i;
39 if (inet_aton(argv[i], &multicastSource) == 0) {
40 fprintf(stderr, "IPv4 source address expected");
41 return -1;
42 }
43 ++i;
44 }
45 }
46
47 int fd = socket(socketFamily, SOCK_DGRAM, 0);
48 if (fd < 0) {
49 perror("socket");
50 return -1;
51 }
52
53 sockaddr_storage saddr;
54 memset(&saddr, 0, sizeof(saddr));
55 if (socketFamily == AF_INET) {
56 sockaddr_in *sa = (sockaddr_in *) &saddr;
57 sa->sin_family = AF_INET;
58 sa->sin_port = htons(TEST_PORT);
59 sa->sin_addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP);
60 } else {
61 sockaddr_in6 *sa = (sockaddr_in6 *) &saddr;
62 sa->sin6_family = AF_INET6;
63 sa->sin6_port = htons(TEST_PORT);
64 // ff01::1 (all nodes multicast)
65 sa->sin6_addr.s6_addr[0] = 0xff;
66 sa->sin6_addr.s6_addr[1] = 0x01;
67 sa->sin6_addr.s6_addr[15] = 0x01;
68 }
69
70 if (multicastSource.s_addr) {
71 if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_IF,
72 &multicastSource, sizeof(multicastSource)) < 0) {
73 perror("setsockopt IP_MULTICAST_IF");
74 return -1;
75 }
76 }
77
78 const char *buffer = "hello world";
79 unsigned length = strlen(buffer);
80 int status = sendto(fd, buffer, length, 0, (sockaddr *) &saddr,
81 socketFamily == AF_INET ? sizeof(sockaddr_in) : sizeof(sockaddr_in6));
82 if (status < length) {
83 if (status < 0)
84 perror("sendto");
85 else if (status == 0)
86 printf("no data sent!\n");
87 else
88 printf("not all data sent!\n");
89 } else
90 printf("send(): success\n");
91
92 close(fd);
93 return 0;
94 }
95