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/*
* Netris -- A free networked version of T*tris
* Copyright (C) 1994,1995,1996 Mark H. Weaver <mhw@netris.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* $Id: inet.c,v 1.18 1996/02/09 08:22:13 mhw Exp $
*/
#include "netris.h"
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <string.h>
#include <errno.h>
#define HEADER_SIZE sizeof(netint2[2])
static MyEventType NetGenFunc(EventGenRec *gen, MyEvent *event);
static int sock = -1;
static EventGenRec netGen = { NULL, 0, FT_read, -1, NetGenFunc, EM_net };
static char netBuf[64];
static int netBufSize, netBufGoal = HEADER_SIZE;
static int isServer, lostConn, gotEndConn;
ExtFunc void InitNet(void)
{
lostConn = 0;
gotEndConn = 0;
AtExit(CloseNet);
}
ExtFunc int WaitForConnection(char *portStr)
{
struct sockaddr_in addr;
struct hostent *host;
int sockListen;
int addrLen;
short port;
int val1;
struct linger val2;
if (portStr)
port = atoi(portStr); /* XXX Error checking */
else
port = DEFAULT_PORT;
memset(&addr, 0, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_addr.s_addr = htonl(INADDR_ANY);
addr.sin_port = htons(port);
sockListen = socket(AF_INET, SOCK_STREAM, 0);
if (sockListen < 0)
die("socket");
val1 = 1;
setsockopt(sockListen, SOL_SOCKET, SO_REUSEADDR,
(void *)&val1, sizeof(val1));
if (bind(sockListen, (struct sockaddr *)&addr, sizeof(addr)) < 0)
die("bind");
if (listen(sockListen, 1) < 0)
die("listen");
addrLen = sizeof(addr);
sock = accept(sockListen, (struct sockaddr *)&addr, &addrLen);
if (sock < 0)
die("accept");
close(sockListen);
val2.l_onoff = 1;
val2.l_linger = 0;
setsockopt(sock, SOL_SOCKET, SO_LINGER,
(void *)&val2, sizeof(val2));
netGen.fd = sock;
strcpy(opponentHost, "???");
if (addr.sin_family == AF_INET) {
host = gethostbyaddr((void *)&addr.sin_addr,
sizeof(struct in_addr), AF_INET);
if (host) {
strncpy(opponentHost, host->h_name, sizeof(opponentHost)-1);
opponentHost[sizeof(opponentHost)-1] = 0;
}
}
AddEventGen(&netGen);
isServer = 1;
return 0;
}
ExtFunc int InitiateConnection(char *hostStr, char *portStr)
{
struct sockaddr_in addr;
struct hostent *host;
short port;
int mySock;
if (portStr)
port = atoi(portStr); /* XXX Error checking */
else
port = DEFAULT_PORT;
host = gethostbyname(hostStr);
if (!host)
die("gethostbyname");
assert(host->h_addrtype == AF_INET);
strncpy(opponentHost, host->h_name, sizeof(opponentHost)-1);
opponentHost[sizeof(opponentHost)-1] = 0;
again:
memset(&addr, 0, sizeof(addr));
addr.sin_family = host->h_addrtype;
memcpy(&addr.sin_addr, host->h_addr, host->h_length);
addr.sin_port = htons(port);
mySock = socket(AF_INET, SOCK_STREAM, 0);
if (mySock < 0)
die("socket");
if (connect(mySock, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
if (errno != ECONNREFUSED)
die("connect");
close(mySock);
sleep(1);
goto again;
}
netGen.fd = sock = mySock;
AddEventGen(&netGen);
return 0;
}
static MyEventType NetGenFunc(EventGenRec *gen, MyEvent *event)
{
int result;
short type, size;
netint2 data[2];
result = MyRead(sock, netBuf + netBufSize, netBufGoal - netBufSize);
if (result < 0) {
lostConn = 1;
return E_lostConn;
}
netBufSize += result;
if (netBufSize < netBufGoal)
return E_none;
memcpy(data, netBuf, sizeof(data));
type = ntoh2(data[0]);
size = ntoh2(data[1]);
if (size >= sizeof(netBuf))
fatal("Received an invalid packet (too large), possibly an attempt\n"
" to exploit a vulnerability in versions before 0.52 !");
netBufGoal = size;
if (netBufSize < netBufGoal)
return E_none;
netBufSize = 0;
netBufGoal = HEADER_SIZE;
event->u.net.type = type;
event->u.net.size = size - HEADER_SIZE;
event->u.net.data = netBuf + HEADER_SIZE;
if (type == NP_endConn) {
gotEndConn = 1;
return E_lostConn;
}
else if (type == NP_byeBye) {
lostConn = 1;
return E_lostConn;
}
return E_net;
}
ExtFunc void CheckNetConn(void)
{
}
ExtFunc void SendPacket(NetPacketType type, int size, void *data)
{
netint2 header[2];
header[0] = hton2(type);
header[1] = hton2(size + HEADER_SIZE);
if (MyWrite(sock, header, HEADER_SIZE) != HEADER_SIZE)
die("write");
if (size > 0 && data && MyWrite(sock, data, size) != size)
die("write");
}
ExtFunc void CloseNet(void)
{
MyEvent event;
if (sock >= 0) {
if (!lostConn) {
SendPacket(NP_endConn, 0, NULL);
if (isServer) {
while (!lostConn)
WaitMyEvent(&event, EM_net);
}
else {
while (!gotEndConn)
WaitMyEvent(&event, EM_net);
SendPacket(NP_byeBye, 0, NULL);
}
}
close(sock);
sock = -1;
}
if (netGen.next)
RemoveEventGen(&netGen);
}
/*
* vi: ts=4 ai
* vim: noai si
*/
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