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/*-
* Copyright (c) 1985, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
static char sccsid[] = "@(#)acksend.c 8.1 (Berkeley) 6/6/93";
#endif /* not lint */
#ifdef sgi
#ident "$Revision: 1.6 $"
#endif
#include "globals.h"
struct tsp *answer;
extern u_short sequence;
void
xmit(type, seq, addr)
int type;
u_int seq;
struct sockaddr_in *addr;
{
static struct tsp msg;
msg.tsp_type = type;
msg.tsp_seq = seq;
msg.tsp_vers = TSPVERSION;
(void)strcpy(msg.tsp_name, hostname);
bytenetorder(&msg);
if (sendto(sock, (char *)&msg, sizeof(struct tsp), 0,
(struct sockaddr*)addr, sizeof(struct sockaddr)) < 0) {
trace_sendto_err(addr->sin_addr);
}
}
/*
* Acksend implements reliable datagram transmission by using sequence
* numbers and retransmission when necessary.
* If `name' is ANYADDR, this routine implements reliable broadcast.
*
* Because this function calls readmsg(), none of its args may be in
* a message provided by readmsg().
*/
struct tsp *
acksend(message, addr, name, ack, net, bad)
struct tsp *message; /* this message */
struct sockaddr_in *addr; /* to here */
char *name;
int ack; /* look for this ack */
struct netinfo *net; /* receive from this network */
int bad; /* 1=losing patience */
{
struct timeval twait;
int count;
long msec;
message->tsp_vers = TSPVERSION;
message->tsp_seq = sequence;
if (trace) {
fprintf(fd, "acksend: to %s: ",
(name == ANYADDR ? "broadcast" : name));
print(message, addr);
}
bytenetorder(message);
msec = 200;
count = bad ? 1 : 5; /* 5 packets in 6.4 seconds */
answer = 0;
do {
if (!answer) {
/* do not go crazy transmitting just because the
* other guy cannot keep our sequence numbers
* straight.
*/
if (sendto(sock, (char *)message, sizeof(struct tsp),
0, (struct sockaddr*)addr,
sizeof(struct sockaddr)) < 0) {
trace_sendto_err(addr->sin_addr);
break;
}
}
mstotvround(&twait, msec);
answer = readmsg(ack, name, &twait, net);
if (answer != 0) {
if (answer->tsp_seq != sequence) {
if (trace)
fprintf(fd,"acksend: seq # %u!=%u\n",
answer->tsp_seq, sequence);
continue;
}
break;
}
msec *= 2;
} while (--count > 0);
sequence++;
return(answer);
}
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