2 * Copyright (c) 1985, 1993
3 * The Regents of the University of California. All rights reserved.
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6 * modification, are permitted provided that the following conditions
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14 * may be used to endorse or promote products derived from this software
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32 static char sccsid[] = "@(#)acksend.c 8.1 (Berkeley) 6/6/93";
34 static const char rcsid[] =
42 extern u_short sequence;
45 xmit(int type, u_int seq, struct sockaddr_in *addr)
47 static struct tsp msg;
51 msg.tsp_vers = TSPVERSION;
52 (void)strcpy(msg.tsp_name, hostname);
54 if (sendto(sock, (char *)&msg, sizeof(struct tsp), 0,
55 (struct sockaddr*)addr, sizeof(struct sockaddr)) < 0) {
56 trace_sendto_err(addr->sin_addr);
62 * Acksend implements reliable datagram transmission by using sequence
63 * numbers and retransmission when necessary.
64 * If `name' is ANYADDR, this routine implements reliable broadcast.
66 * Because this function calls readmsg(), none of its args may be in
67 * a message provided by readmsg().
68 * message this message
70 * ack look for this ack
71 * net receive from this network
72 * bad 1=losing patience
75 acksend(struct tsp *message, struct sockaddr_in *addr, char *name,
76 int ack, struct netinfo *net, int bad)
82 message->tsp_vers = TSPVERSION;
83 message->tsp_seq = sequence;
85 fprintf(fd, "acksend: to %s: ",
86 (name == ANYADDR ? "broadcast" : name));
89 bytenetorder(message);
92 count = bad ? 1 : 5; /* 5 packets in 6.4 seconds */
96 /* do not go crazy transmitting just because the
97 * other guy cannot keep our sequence numbers
100 if (sendto(sock, (char *)message, sizeof(struct tsp),
101 0, (struct sockaddr*)addr,
102 sizeof(struct sockaddr)) < 0) {
103 trace_sendto_err(addr->sin_addr);
108 mstotvround(&twait, msec);
109 answer = readmsg(ack, name, &twait, net);
111 if (answer->tsp_seq != sequence) {
113 fprintf(fd,"acksend: seq # %u!=%u\n",
114 answer->tsp_seq, sequence);
121 } while (--count > 0);