sic.c

   1 /*
   2  * (C)opyright MMV-MMVI Anselm R. Garbe <garbeam at gmail dot com>
   3  * (C)opyright MMV-MMVI Nico Golde <nico at ngolde dot de>
   4  * See LICENSE file for license details.
   5  */
   6
   7 #include <errno.h>
   8 #include <netdb.h>
   9 #include <netinet/in.h>
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <string.h>
  13 #include <sys/socket.h>
  14 #include <time.h>
  15
  16 #define PINGTIMEOUT 300
  17 #define MAXMSG 4096
  18
  19 enum { Tnick, Tuser, Tcmd, Tchan, Targ, Ttext, Tlast };
  20
  21 /* CUSTOMIZE */
  22 static char *server = "irc.oftc.net";
  23 static int port = 6667;
  24 static char *nick = NULL;
  25 static char *fullname = NULL;
  26 static char *password = NULL;
  27
  28 static char bufin[MAXMSG], bufout[MAXMSG];
  29 static char channel[256];
  30 static int srv;
  31 static time_t trespond;
  32
  33 static int
  34 getline(int fd, unsigned int len, char *buf)
  35 {
  36         unsigned int i = 0;
  37         char c;
  38         do {
  39                 if(read(fd, &c, sizeof(char)) != sizeof(char))
  40                         return -1;
  41                 buf[i++] = c;
  42         }
  43         while(c != '\n' && i < len);
  44         buf[i - 1] = 0;
  45         return 0;
  46 }
  47
  48 static void
  49 pout(char *channel, char *msg)
  50 {
  51         static char timestr[18];
  52         time_t t = time(0);
  53
  54         strftime(timestr, sizeof(timestr), "%a %R", localtime(&t));
  55         fprintf(stdout, "%s: %s %s\n", channel, timestr, msg);
  56 }
  57
  58 static void
  59 privmsg(char *channel, char *msg)
  60 {
  61         snprintf(bufout, sizeof(bufout), "<%s> %s", nick, msg);
  62         pout(channel, bufout);
  63         snprintf(bufout, sizeof(bufout), "PRIVMSG %s :%s\r\n", channel, msg);
  64         write(srv, bufout, strlen(bufout));
  65 }
  66
  67 static void
  68 parsein(char *msg)
  69 {
  70         char *p;
  71
  72         if(msg[0] != '/') {
  73                 privmsg(channel, msg);
  74                 return;
  75         }
  76         if((p = strchr(&msg[3], ' ')))
  77                 *(p++) = 0;
  78         switch (msg[1]) {
  79         default:
  80                 snprintf(bufout, sizeof(bufout), "%s\r\n", &msg[1]);
  81                 break;
  82         case 'j':
  83                 if(msg[3] == '#')
  84                         snprintf(bufout, sizeof(bufout), "JOIN %s\r\n", &msg[3]);
  85                 else if(p) {
  86                         privmsg(&msg[3], p + 1);
  87                         return;
  88                 }
  89                 break;
  90         case 'l':
  91                 if(p)
  92                         snprintf(bufout, sizeof(bufout), "PART %s :%s\r\n", &msg[3], p);
  93                 else
  94                         snprintf(bufout, sizeof(bufout), "PART %s :sic\r\n", &msg[3]);
  95                 break;
  96         case 'm':
  97                 privmsg(&msg[3], p);
  98                 return;
  99         case 's':
 100                 strncpy(channel, &msg[3], sizeof(channel));
 101                 return;
 102         case 't':
 103                 snprintf(bufout, sizeof(bufout), "TOPIC %s :%s\r\n", &msg[3], p);
 104                 break;
 105         }
 106         write(srv, bufout, strlen(bufout));
 107 }
 108
 109 static unsigned int
 110 tokenize(char **result, unsigned int reslen, char *str, char delim)
 111 {
 112         char *p, *n;
 113         unsigned int i = 0;
 114
 115         if(!str)
 116                 return 0;
 117         for(n = str; *n == delim; n++);
 118         p = n;
 119         for(i = 0; *n != 0;) {
 120                 if(i == reslen)
 121                         return i;
 122                 if(*n == delim) {
 123                         *n = 0;
 124                         if(strlen(p))
 125                                 result[i++] = p;
 126                         p = ++n;
 127                 } else
 128                         n++;
 129         }
 130         if((i < reslen) && (p < n) && strlen(p))
 131                 result[i++] = p;
 132         return i;       /* number of tokens */
 133 }
 134
 135 static void
 136 parsesrv(char *msg)
 137 {
 138         char *argv[Tlast], *cmd, *p;
 139         int i;
 140         if(!msg || !(*msg))
 141                 return;
 142
 143         for(i = 0; i < Tlast; i++)
 144                 argv[i] = NULL;
 145
 146         /*
 147            <bufout>  ::= [':' <prefix> <SPACE> ] <command> <params> <crlf>
 148            <prefix>   ::= <servername> | <nick> [ '!' <user> ] [ '@' <server> ]
 149            <command>  ::= <letter> { <letter> } | <number> <number> <number>
 150            <SPACE>    ::= ' ' { ' ' }
 151            <params>   ::= <SPACE> [ ':' <trailing> | <middle> <params> ]
 152            <middle>   ::= <Any *non-empty* sequence of octets not including SPACE
 153            or NUL or CR or LF, the first of which may not be ':'>
 154            <trailing> ::= <Any, possibly *empty*, sequence of octets not including NUL or CR or LF>
 155            <crlf>     ::= CR LF
 156          */
 157         if(msg[0] == ':') { /* check prefix */
 158                 p = strchr(msg, ' ');
 159                 *p = 0;
 160                 for(++p; *p == ' '; p++);
 161                 cmd = p;
 162                 argv[Tnick] = &msg[1];
 163                 if((p = strchr(msg, '!'))) {
 164                         *p = 0;
 165                         argv[Tuser] = ++p;
 166                 }
 167         } else
 168                 cmd = msg;
 169
 170         /* remove CRLFs */
 171         for(p = cmd; p && *p != 0; p++)
 172                 if(*p == '\r' || *p == '\n')
 173                         *p = 0;
 174
 175         if((p = strchr(cmd, ':'))) {
 176                 *p = 0;
 177                 argv[Ttext] = ++p;
 178         }
 179         tokenize(&argv[Tcmd], Tlast - Tcmd, cmd, ' ');
 180
 181         if(!strncmp("PONG", argv[Tcmd], 5)) {
 182                 return;
 183         } else if(!strncmp("PING", argv[Tcmd], 5)) {
 184                 snprintf(bufout, sizeof(bufout), "PONG %s\r\n", argv[Ttext]);
 185                 write(srv, bufout, strlen(bufout));
 186                 return;
 187         } else if(!argv[Tnick] || !argv[Tuser]) {       /* server command */
 188                 snprintf(bufout, sizeof(bufout), "%s", argv[Ttext] ? argv[Ttext] : "");
 189                 pout(server, bufout);
 190                 return;
 191         } else if(!strncmp("ERROR", argv[Tcmd], 6))
 192                 snprintf(bufout, sizeof(bufout), "-!- error %s",
 193                                 argv[Ttext] ? argv[Ttext] : "unknown");
 194         else if(!strncmp("JOIN", argv[Tcmd], 5)) {
 195                 if(argv[Ttext]!=NULL){
 196                         p = strchr(argv[Ttext], ' ');
 197                 if(p)
 198                         *p = 0;
 199                 }
 200                 argv[Tchan] = argv[Ttext];
 201                 snprintf(bufout, sizeof(bufout), "-!- %s(%s) has joined %s",
 202                                 argv[Tnick], argv[Tuser], argv[Ttext]);
 203         } else if(!strncmp("PART", argv[Tcmd], 5)) {
 204                 snprintf(bufout, sizeof(bufout), "-!- %s(%s) has left %s",
 205                                 argv[Tnick], argv[Tuser], argv[Tchan]);
 206         } else if(!strncmp("MODE", argv[Tcmd], 5))
 207                 snprintf(bufout, sizeof(bufout), "-!- %s changed mode/%s -> %s %s",
 208                                 argv[Tnick], argv[Tcmd + 1],
 209                                 argv[Tcmd + 2], argv[Tcmd + 3]);
 210         else if(!strncmp("QUIT", argv[Tcmd], 5))
 211                 snprintf(bufout, sizeof(bufout), "-!- %s(%s) has quit \"%s\"",
 212                                 argv[Tnick], argv[Tuser],
 213                                 argv[Ttext] ? argv[Ttext] : "");
 214         else if(!strncmp("NICK", argv[Tcmd], 5))
 215                 snprintf(bufout, sizeof(bufout), "-!- %s changed nick to %s",
 216                                 argv[Tnick], argv[Ttext]);
 217         else if(!strncmp("TOPIC", argv[Tcmd], 6))
 218                 snprintf(bufout, sizeof(bufout), "-!- %s changed topic to \"%s\"",
 219                                 argv[Tnick], argv[Ttext] ? argv[Ttext] : "");
 220         else if(!strncmp("KICK", argv[Tcmd], 5))
 221                 snprintf(bufout, sizeof(bufout), "-!- %s kicked %s (\"%s\")",
 222                                 argv[Tnick], argv[Targ],
 223                                 argv[Ttext] ? argv[Ttext] : "");
 224         else if(!strncmp("NOTICE", argv[Tcmd], 7))
 225                 snprintf(bufout, sizeof(bufout), "-!- \"%s\")",
 226                                 argv[Ttext] ? argv[Ttext] : "");
 227         else if(!strncmp("PRIVMSG", argv[Tcmd], 8)) snprintf(bufout, sizeof(bufout), "<%s> %s",
 228                                 argv[Tnick], argv[Ttext] ? argv[Ttext] : "");
 229         if(!argv[Tchan] || !strncmp(argv[Tchan], nick, strlen(nick)))
 230                 pout(argv[Tnick], bufout);
 231         else
 232                 pout(argv[Tchan], bufout);
 233 }
 234
 235 int
 236 main(int argc, char *argv[])
 237 {
 238         int i;
 239         struct timeval tv;
 240         struct hostent *hp;
 241         struct sockaddr_in addr = { 0 };
 242         char ping[256];
 243         fd_set rd;
 244
 245         nick = fullname = getenv("USER");
 246         for(i = 1; (i < argc) && (argv[i][0] == '-'); i++) {
 247                 switch (argv[i][1]) {
 248                 default:
 249                         fputs("usage: sic [-s server] [-p port] [-n nick]"
 250                                         " [-k keyword] [-f fullname] [-v]\n", stderr);
 251                         exit(EXIT_FAILURE);
 252                         break;
 253                 case 's':
 254                         server = argv[i++];
 255                         break;
 256                 case 'p':
 257                         port = atoi(argv[i++]);
 258                         break;
 259                 case 'n':
 260                         nick = argv[i++];
 261                         break;
 262                 case 'k':
 263                         password = argv[i++];
 264                         break;
 265                 case 'f':
 266                         fullname = argv[i++];
 267                         break;
 268                 case 'v':
 269                         fputs("sic-"VERSION", (C)opyright MMVI Anselm R. Garbe\n", stdout);
 270                         exit(EXIT_SUCCESS);
 271                         break;
 272                 }
 273         }
 274
 275         /* init */
 276         if((srv = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
 277                 fprintf(stderr, "sic: cannot connect server '%s'\n", server);
 278                 exit(EXIT_FAILURE);
 279         }
 280         hp = gethostbyname(server);
 281         addr.sin_family = AF_INET;
 282         addr.sin_port = htons(port);
 283         bcopy(hp->h_addr, &addr.sin_addr, hp->h_length);
 284         if(connect(srv, (struct sockaddr *) &addr, sizeof(struct sockaddr_in))) {
 285                 close(srv);
 286                 fprintf(stderr, "sic: cannot connect server '%s'\n", server);
 287                 exit(EXIT_FAILURE);
 288         }
 289
 290         /* login */
 291         if(password)
 292                 snprintf(bufout, sizeof(bufout),
 293                                 "PASS %s\r\nNICK %s\r\nUSER %s localserver %s :%s\r\n",
 294                                 password, nick, nick, server, fullname ? fullname : nick);
 295         else
 296                 snprintf(bufout, sizeof(bufout), "NICK %s\r\nUSER %s localserver %s :%s\r\n",
 297                                  nick, nick, server, fullname ? fullname : nick);
 298         write(srv, bufout, strlen(bufout));
 299
 300         snprintf(ping, sizeof(ping), "PING %s\r\n", server);
 301         channel[0] = 0;
 302         setbuf(stdout, NULL); /* unbuffered stdout */
 303         for(;;) {
 304                 FD_ZERO(&rd);
 305                 FD_SET(0, &rd);
 306                 FD_SET(srv, &rd);
 307                 tv.tv_sec = 120;
 308                 tv.tv_usec = 0;
 309                 i = select(srv + 1, &rd, 0, 0, &tv);
 310                 if(i < 0) {
 311                         if(errno == EINTR)
 312                                 continue;
 313                         perror("sic: error on select()");
 314                         exit(EXIT_FAILURE);
 315                 } else if(i == 0) {
 316                         if(time(NULL) - trespond >= PINGTIMEOUT) {
 317                                 pout(server, "-!- sic shutting down: parseing timeout");
 318                                 exit(EXIT_FAILURE);
 319                         }
 320                         write(srv, ping, strlen(ping));
 321                         continue;
 322                 }
 323                 if(FD_ISSET(srv, &rd)) {
 324                         if(getline(srv, sizeof(bufin), bufin) == -1) {
 325                                 perror("sic: remote server closed connection");
 326                                 exit(EXIT_FAILURE);
 327                         }
 328                         parsesrv(bufin);
 329                         trespond = time(NULL);
 330                 }
 331                 if(FD_ISSET(0, &rd)) {
 332                         if(getline(0, sizeof(bufin), bufin) == -1) {
 333                                 perror("sic: broken pipe");
 334                                 exit(EXIT_FAILURE);
 335                         }
 336                         parsein(bufin);
 337                 }
 338         }
 339
 340         return 0;
 341 }