inet.c

   1 /*
   2  * Netris -- A free networked version of T*tris
   3  * Copyright (C) 1994,1995,1996  Mark H. Weaver <mhw@netris.org>
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License
   7  * as published by the Free Software Foundation; either version 2
   8  * of the License, or (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18  *
  19  * $Id: inet.c,v 1.18 1996/02/09 08:22:13 mhw Exp $
  20  */
  21
  22 #include "netris.h"
  23
  24 #include <sys/types.h>
  25 #include <unistd.h>
  26 #include <stdlib.h>
  27 #include <sys/socket.h>
  28 #include <netinet/in.h>
  29 #include <netdb.h>
  30 #include <string.h>
  31 #include <errno.h>
  32 #include <setjmp.h>
  33
  34 #include "inet.h"
  35
  36 #define HEADER_SIZE sizeof(netint2[2])
  37 #define HEADER_SIZE3 sizeof(netint4[3])
  38
  39 MyEventType NetGenFunc(EventGenRec *gen, MyEvent *event);
  40 EventGenRec netGen = {
  41         NULL, 0, FT_read, -1, NetGenFunc, EM_net, 0, "\0", 0, HEADER_SIZE3
  42 };
  43
  44
  45 static sigjmp_buf close_env;
  46
  47 void CatchInt(int sig)
  48 {
  49         siglongjmp(close_env, 1);
  50 }
  51
  52 int InitiateConnection(char *hostStr, short port)
  53 { //connect to host
  54         struct sockaddr_in addr;
  55         struct hostent *host;
  56
  57         if (sigsetjmp(close_env, 1))
  58                 exit(0);
  59         signal(SIGINT, CatchInt);  //handle exit (^C)
  60         AtExit(CloseNet);
  61         host = gethostbyname(hostStr);
  62         if (!host)
  63                 die("gethostbyname");
  64         assert(host->h_addrtype == AF_INET);
  65  again:
  66         memset(&addr, 0, sizeof(addr));
  67         addr.sin_family = host->h_addrtype;
  68         memcpy(&addr.sin_addr, host->h_addr, host->h_length);
  69         addr.sin_port = htons(port);
  70         if ((netGen.fd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
  71                 die("socket");
  72         if (connect(netGen.fd, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
  73                 if (errno != ECONNREFUSED)
  74                         die("connect");
  75                 close(netGen.fd);
  76                 sleep(1);
  77                 goto again;
  78         }
  79         AddEventGen(&netGen);
  80         return 0;
  81 }
  82
  83 void HandShake(void)
  84 { //talk to your host
  85         MyEvent event;
  86
  87         {
  88                 netint4 versiondata[2];
  89                 versiondata[0] = hton4(MAJOR_VERSION);
  90                 versiondata[1] = hton4(PROTOCOL_VERSION);
  91                 SendPacket(0, NP_hello, sizeof(versiondata), versiondata);
  92         }
  93
  94         do {
  95                 if (WaitMyEvent(&event, EM_net) == E_net)
  96                         switch (event.u.net.type) {
  97                         case NP_hello:
  98                         {
  99                                 me = event.u.net.uid;
 100                                 memcpy(&Players[me], &Players[0], sizeof(_Player));
 101                                 fprintf(stderr, "Accepted (%s) as #%d (%s)\n",
 102                                         event.u.net.data, me, Players[me].name);
 103                                 SendPacket(0, NP_newPlayer,
 104                                         sizeof(_Player) - sizeof(Players[me].host),
 105                                         &Players[me]);
 106                                 break;
 107                         }
 108                         case NP_team:
 109                         { //receive your teamnumber
 110                                 memcpy(&Players[event.u.net.uid].team, event.u.net.data,
 111                                         event.u.net.size);
 112                                 break;
 113                         } //NP_team
 114                         case NP_gamedata:
 115                         {
 116                                 static struct {
 117                                         int playerflags;
 118                                         int maxplayers;  //1
 119                                         int started;     //2
 120                                         int continuous;  //3
 121                                         long seed;       //4
 122                                         int initspeed;   //5
 123                                 } data;
 124
 125                                 memcpy(&data, event.u.net.data, event.u.net.size);
 126                                 memcpy(&Players[me].flags, &data, sizeof(data.playerflags));
 127                                 memcpy(&Players[me].flags, &data, sizeof(data.playerflags));
 128                                 memcpy(&Game, &data.maxplayers,
 129                                         sizeof(data) - sizeof(data.playerflags));
 130                                 break;
 131                         } //NP_gamedata
 132                         case NP_error:
 133                         {
 134                                 fprintf(stderr, "Rejected by server: %s\n", event.u.net.data);
 135                                 exit(1);
 136                         } //NP_error
 137                         default:
 138                                 break;
 139                         }
 140                 else
 141                         fatal("Hm, the party apparantly ended prematurely.");
 142         }
 143         while (event.u.net.type != NP_gamedata);
 144 }
 145
 146
 147 MyEventType NetGenFunc(EventGenRec *gen, MyEvent *event)
 148 { //receive
 149         int result;
 150         short uid, type, size;
 151         netint4 *data = (netint4*)&(gen->buf);
 152
 153         result = MyRead(gen->fd, gen->buf + gen->bufSize,
 154                 gen->bufGoal - gen->bufSize);
 155         if (result < 0) {
 156                 close(gen->fd);
 157                 gen->fd = -1;
 158                 return E_lostConn;
 159         }
 160         gen->bufSize += result;
 161         if (gen->bufSize < gen->bufGoal)
 162                 return E_none;
 163         // *ugly* memcpy(data, gen->buf, sizeof(data));
 164         uid = ntoh4(data[0]);
 165         type = ntoh4(data[1]);
 166         size = ntoh4(data[2]);
 167         gen->bufGoal = size;
 168         if (gen->bufSize < gen->bufGoal)
 169                 return E_none;
 170         gen->bufSize = 0;
 171         gen->bufGoal = HEADER_SIZE3;
 172         event->u.net.sender = gen->player;
 173         event->u.net.uid = uid;
 174         event->u.net.type = type;
 175         event->u.net.size = size - HEADER_SIZE3;
 176         event->u.net.data = gen->buf + HEADER_SIZE3;
 177         if (type == NP_endConn) return E_lostConn;
 178         return E_net;
 179 }
 180
 181 void SendPacket(short uid, NetPacketType type, int size, void *data)
 182 { //send shit to server
 183         netint4 header[3];
 184
 185         header[0] = hton4(uid);
 186         header[1] = hton4(type);
 187         header[2] = hton4(size + HEADER_SIZE3);
 188         if (MyWrite(netGen.fd, header, HEADER_SIZE3) != HEADER_SIZE3)
 189                 die("write (header)");
 190         if (size > 0 && data && MyWrite(netGen.fd, data, size) != size)
 191                 die("write");
 192 }
 193
 194 void CloseNet(void)
 195 { //kick some connection's ass!
 196         MyEvent event;
 197
 198         if (netGen.fd >= 0) {
 199                 SendPacket(0, NP_endConn, 0, NULL);
 200                 close(netGen.fd);
 201                 netGen.fd = -1;
 202         }
 203         if (netGen.next)
 204                 RemoveEventGen(&netGen);
 205 }
 206