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
|
/*
** broadcaster.c -- a datagram "client" like talker.c, except
** this one can broadcast
*/
#include "common.h"
int main(int argc, char **argv)
{
int fd;
struct sockaddr_in6 addr;
int broadcast = 1;
/* assemble packet, parse cmd line */
if (argc < 3 || argc > 4) {
fprintf(stderr, "usage: %s interface task [message|-]\n", argv[0]);
exit(1);
}
char buf[MAXBUFLEN],
*task = argv[2],
*message = (argc == 4) ? argv[3] : "";
int task_len = strlen(task),
total_len = task_len + 1;
strcpy(buf, task);
buf[task_len] = 0;
if (strcmp(message, "-") == 0) {
/* read payload from stdin */
int i;
while ((MAXBUFLEN - total_len - 1 > 0)
&& ((i = read(0, &(buf[total_len]), MAXBUFLEN - total_len - 1)) > 0))
total_len += i;
ENP(i, "read(stdin)");
if (read(0, &i, 1) != 0) {
fprintf(stderr, "payload to long: max %d bytes\n", MAXBUFLEN - 1);
exit(1);
}
}else{
/* use cmd line for payload */
total_len += strlen(message);
if (total_len <= MAXBUFLEN)
strcpy(buf + 1 + task_len, message);
}
if (total_len > MAXBUFLEN) {
fprintf(stderr,"payload to long: max %d bytes, was %d\n",
MAXBUFLEN - 1, total_len);
exit(1);
}
/* setup socket */
ENP((fd = socket(AF_INET6, SOCK_DGRAM, 0)), "socket");
addr.sin6_family = AF_INET6;
addr.sin6_port = htons(SERVERPORT);
addr.sin6_flowinfo = 0;
inet_pton(AF_INET6, "ff02::1", &(addr.sin6_addr));
if ((addr.sin6_scope_id = if_nametoindex(argv[1])) == 0) {
fprintf(stderr, "interface not found\n");
exit(1);
}
/* send packet */
ENP(sendto(fd, buf, total_len, 0, (struct sockaddr *) &addr, sizeof addr),
"sendto");
return 0;
}
|
