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
  20 #include "netris.h"
  21
  22 #include <sys/types.h>
  23 #include <unistd.h>
  24 #include <stdlib.h>
  25 #include <sys/socket.h>
  26 #include <netinet/in.h>
  27 #include <netdb.h>
  28 #include <string.h>
  29 #include <errno.h>
  30 #include <setjmp.h>
  31
  32 #include "inet.h"
  33
  34 #define HEADER_SIZE sizeof(netint2[2])
  35 #define HEADER_SIZE3 sizeof(netint4[3])
  36
  37 MyEventType NetGenFunc(EventGenRec *gen, MyEvent *event);
  38 EventGenRec netGen = {
  39         NULL, 0, FT_read, -1, NetGenFunc, EM_net, 0, "\0", 0, HEADER_SIZE3
  40 };
  41
  42
  43 static sigjmp_buf close_env;
  44
  45 void CatchInt(int sig)
  46 {
  47         siglongjmp(close_env, 1);
  48 }
  49
  50 int InitiateConnection(char *hostStr, short port)
  51 { //connect to host
  52         struct sockaddr_in addr;
  53         struct hostent *host;
  54
  55         if (sigsetjmp(close_env, 1))
  56                 exit(0);
  57         signal(SIGINT, CatchInt);  //handle exit (^C)
  58         AtExit(CloseNet);
  59         host = gethostbyname(hostStr);
  60         if (!host)
  61                 die("gethostbyname");
  62         assert(host->h_addrtype == AF_INET);
  63  again:
  64         memset(&addr, 0, sizeof(addr));
  65         addr.sin_family = host->h_addrtype;
  66         memcpy(&addr.sin_addr, host->h_addr, host->h_length);
  67         addr.sin_port = htons(port);
  68         if ((netGen.fd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
  69                 die("socket");
  70         if (connect(netGen.fd, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
  71                 if (errno != ECONNREFUSED)
  72                         die("connect");
  73                 close(netGen.fd);
  74                 sleep(1);
  75                 goto again;
  76         }
  77         AddEventGen(&netGen);
  78         return 0;
  79 }
  80
  81 void HandShake(void)
  82 { //talk to your host
  83         MyEvent event;
  84
  85         {
  86                 netint4 versiondata[2];
  87                 versiondata[0] = hton4(MAJOR_VERSION);
  88                 versiondata[1] = hton4(PROTOCOL_VERSION);
  89                 SendPacket(0, NP_hello, sizeof(versiondata), versiondata);
  90         }
  91
  92         do {
  93                 if (WaitMyEvent(&event, EM_net) == E_net)
  94                         switch (event.u.net.type) {
  95                         case NP_hello:
  96                         {
  97                                 me = event.u.net.uid;
  98                                 memcpy(&Players[me], &Players[0], sizeof(_Player));
  99                                 fprintf(stderr, "Accepted (%s) as #%d (%s)\n",
 100                                         event.u.net.data, me, Players[me].name);
 101                                 SendPacket(0, NP_newPlayer,
 102                                         sizeof(_Player) - sizeof(Players[me].host),
 103                                         &Players[me]);
 104                                 break;
 105                         }
 106                         case NP_team:
 107                         { //receive your teamnumber
 108                                 memcpy(&Players[event.u.net.uid].team, event.u.net.data,
 109                                         event.u.net.size);
 110                                 break;
 111                         } //NP_team
 112                         case NP_gamedata:
 113                         {
 114                                 static struct {
 115                                         int playerflags;
 116                                         int maxplayers;  //1
 117                                         int started;     //2
 118                                         int continuous;  //3
 119                                         long seed;       //4
 120                                         int initspeed;   //5
 121                                 } data;
 122
 123                                 memcpy(&data, event.u.net.data, event.u.net.size);
 124                                 memcpy(&Players[me].flags, &data, sizeof(data.playerflags));
 125                                 memcpy(&Players[me].flags, &data, sizeof(data.playerflags));
 126                                 memcpy(&Game, &data.maxplayers,
 127                                         sizeof(data) - sizeof(data.playerflags));
 128                                 break;
 129                         } //NP_gamedata
 130                         case NP_error:
 131                         {
 132                                 fprintf(stderr, "Rejected by server: %s\n", event.u.net.data);
 133                                 exit(1);
 134                         } //NP_error
 135                         default:
 136                                 break;
 137                         }
 138                 else
 139                         fatal("Hm, the party apparantly ended prematurely.");
 140         } while (event.u.net.type != NP_gamedata);
 141 }
 142
 143
 144 MyEventType NetGenFunc(EventGenRec *gen, MyEvent *event)
 145 { //receive
 146         int result;
 147         short uid, type, size;
 148         netint4 *data = (netint4*)&(gen->buf);
 149
 150         result = MyRead(gen->fd, gen->buf + gen->bufSize,
 151                 gen->bufGoal - gen->bufSize);
 152         if (result < 0) {
 153                 close(gen->fd);
 154                 gen->fd = -1;
 155                 return E_lostConn;
 156         }
 157         gen->bufSize += result;
 158         if (gen->bufSize < gen->bufGoal)
 159                 return E_none;
 160         // *ugly* memcpy(data, gen->buf, sizeof(data));
 161         uid = ntoh4(data[0]);
 162         type = ntoh4(data[1]);
 163         size = ntoh4(data[2]);
 164         gen->bufGoal = size;
 165         if (gen->bufSize < gen->bufGoal)
 166                 return E_none;
 167         gen->bufSize = 0;
 168         gen->bufGoal = HEADER_SIZE3;
 169         event->u.net.sender = gen->player;
 170         event->u.net.uid = uid;
 171         event->u.net.type = type;
 172         event->u.net.size = size - HEADER_SIZE3;
 173         event->u.net.data = gen->buf + HEADER_SIZE3;
 174         if (type == NP_endConn) return E_lostConn;
 175         return E_net;
 176 }
 177
 178 void SendPacket(short uid, NetPacketType type, int size, void *data)
 179 { //send shit to server
 180         netint4 header[3];
 181
 182         header[0] = hton4(uid);
 183         header[1] = hton4(type);
 184         header[2] = hton4(size + HEADER_SIZE3);
 185         if (MyWrite(netGen.fd, header, HEADER_SIZE3) != HEADER_SIZE3)
 186                 die("write (header)");
 187         if (size > 0 && data && MyWrite(netGen.fd, data, size) != size)
 188                 die("write");
 189 }
 190
 191 void CloseNet(void)
 192 { //kick some connection's ass!
 193         MyEvent event;
 194
 195         if (netGen.fd >= 0) {
 196                 SendPacket(0, NP_endConn, 0, NULL);
 197                 close(netGen.fd);
 198                 netGen.fd = -1;
 199         }
 200         if (netGen.next)
 201                 RemoveEventGen(&netGen);
 202 }
 203