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 <time.h>
  14 #include <unistd.h>
  15 #include <sys/socket.h>
  16 #include <sys/time.h>
  17
  18 #define PINGTIMEOUT 300
  19 #define MAXMSG 4096
  20
  21 enum { Tnick, Tuser, Tcmd, Tchan, Targ, Ttext, Tlast };
  22
  23 static char *server = "irc.oftc.net";
  24 static unsigned short port = 6667;
  25 static char *nick = NULL;
  26 static char *fullname = NULL;
  27 static char *password = NULL;
  28
  29 static char bufin[MAXMSG], bufout[MAXMSG];
  30 static char channel[256];
  31 static int srv;
  32 static time_t trespond;
  33
  34 static int
  35 getline(int fd, unsigned int len, char *buf)
  36 {
  37         unsigned int i = 0;
  38         char c;
  39         do {
  40                 if(read(fd, &c, sizeof(char)) != sizeof(char))
  41                         return -1;
  42                 buf[i++] = c;
  43         }
  44         while(c != '\n' && i < len);
  45         buf[i - 1] = 0;
  46         return 0;
  47 }
  48
  49 static void
  50 pout(char *channel, char *msg)
  51 {
  52         static char timestr[18];
  53         time_t t = time(0);
  54
  55         strftime(timestr, sizeof(timestr), "%a %R", localtime(&t));
  56         fprintf(stdout, "%-8.8s: %s %s\n", channel, timestr, msg);
  57 }
  58
  59 static void
  60 privmsg(char *channel, char *msg)
  61 {
  62         snprintf(bufout, sizeof(bufout), "<%s> %s", nick, msg);
  63         pout(channel, bufout);
  64         snprintf(bufout, sizeof(bufout), "PRIVMSG %s :%s\r\n", channel, msg);
  65         write(srv, bufout, strlen(bufout));
  66 }
  67
  68 static void
  69 parsein(char *msg)
  70 {
  71         char *p;
  72
  73         if(msg[0] == 0)
  74                 return;
  75         if(msg[0] != '/') {
  76                 privmsg(channel, msg);
  77                 return;
  78         }
  79         if(!strncmp(msg + 1, "j ", 2) && (msg[3] == '#'))
  80                 snprintf(bufout, sizeof(bufout), "JOIN %s\r\n", &msg[3]);
  81         else if(!strncmp(msg + 1, "l ", 2))
  82                 snprintf(bufout, sizeof(bufout), "PART %s :sic\r\n", &msg[3]);
  83         else if(!strncmp(msg + 1, "m ", 2)) {
  84                 privmsg(&msg[3], p);
  85                 return;
  86         }
  87         else if(!strncmp(msg + 1, "s ", 2)) {
  88                 strncpy(channel, &msg[3], sizeof(channel));
  89                 return;
  90         }
  91         else if(!strncmp(msg + 1, "t ", 2)) {
  92                 if(p = strchr(&msg[3], ' '))
  93                         *(p++) = 0;
  94                 snprintf(bufout, sizeof(bufout), "TOPIC %s :%s\r\n", &msg[3], p);
  95         }
  96         else
  97                 snprintf(bufout, sizeof(bufout), "%s\r\n", &msg[1]);
  98         write(srv, bufout, strlen(bufout));
  99 }
 100
 101 static unsigned int
 102 tokenize(char **result, unsigned int reslen, char *str, char delim)
 103 {
 104         char *p, *n;
 105         unsigned int i = 0;
 106
 107         if(!str)
 108                 return 0;
 109         for(n = str; *n == delim; n++);
 110         p = n;
 111         for(i = 0; *n != 0;) {
 112                 if(i == reslen)
 113                         return i;
 114                 if(*n == delim) {
 115                         *n = 0;
 116                         if(strlen(p))
 117                                 result[i++] = p;
 118                         p = ++n;
 119                 } else
 120                         n++;
 121         }
 122         if((i < reslen) && (p < n) && strlen(p))
 123                 result[i++] = p;
 124         return i;       /* number of tokens */
 125 }
 126
 127 static void
 128 parsesrv(char *msg)
 129 {
 130         char *argv[Tlast], *cmd, *p;
 131         int i;
 132         if(!msg || !(*msg))
 133                 return;
 134
 135         for(i = 0; i < Tlast; i++)
 136                 argv[i] = NULL;
 137
 138         /*
 139            <bufout>  ::= [':' <prefix> <SPACE> ] <command> <params> <crlf>
 140            <prefix>   ::= <servername> | <nick> [ '!' <user> ] [ '@' <server> ]
 141            <command>  ::= <letter> { <letter> } | <number> <number> <number>
 142            <SPACE>    ::= ' ' { ' ' }
 143            <params>   ::= <SPACE> [ ':' <trailing> | <middle> <params> ]
 144            <middle>   ::= <Any *non-empty* sequence of octets not including SPACE
 145            or NUL or CR or LF, the first of which may not be ':'>
 146            <trailing> ::= <Any, possibly *empty*, sequence of octets not including NUL or CR or LF>
 147            <crlf>     ::= CR LF
 148          */
 149         if(msg[0] == ':') { /* check prefix */
 150                 p = strchr(msg, ' ');
 151                 *p = 0;
 152                 for(++p; *p == ' '; p++);
 153                 cmd = p;
 154                 argv[Tnick] = &msg[1];
 155                 if((p = strchr(msg, '!'))) {
 156                         *p = 0;
 157                         argv[Tuser] = ++p;
 158                 }
 159         } else
 160                 cmd = msg;
 161
 162         /* remove CRLFs */
 163         for(p = cmd; p && *p != 0; p++)
 164                 if(*p == '\r' || *p == '\n')
 165                         *p = 0;
 166
 167         if((p = strchr(cmd, ':'))) {
 168                 *p = 0;
 169                 argv[Ttext] = ++p;
 170         }
 171         tokenize(&argv[Tcmd], Tlast - Tcmd, cmd, ' ');
 172
 173         if(!strncmp("PONG", argv[Tcmd], 5)) {
 174                 return;
 175         } else if(!strncmp("PING", argv[Tcmd], 5)) {
 176                 snprintf(bufout, sizeof(bufout), "PONG %s\r\n", argv[Ttext]);
 177                 write(srv, bufout, strlen(bufout));
 178                 return;
 179         } else if(!argv[Tnick] || !argv[Tuser]) {       /* server command */
 180                 snprintf(bufout, sizeof(bufout), "%s", argv[Ttext] ? argv[Ttext] : "");
 181                 pout(server, bufout);
 182                 return;
 183         } else if(!strncmp("ERROR", argv[Tcmd], 6))
 184                 snprintf(bufout, sizeof(bufout), "-!- error %s",
 185                                 argv[Ttext] ? argv[Ttext] : "unknown");
 186         else if(!strncmp("JOIN", argv[Tcmd], 5)) {
 187                 if(argv[Ttext]!=NULL){
 188                         p = strchr(argv[Ttext], ' ');
 189                 if(p)
 190                         *p = 0;
 191                 }
 192                 argv[Tchan] = argv[Ttext];
 193                 snprintf(bufout, sizeof(bufout), "-!- %s(%s) has joined %s",
 194                                 argv[Tnick], argv[Tuser], argv[Ttext]);
 195         } else if(!strncmp("PART", argv[Tcmd], 5)) {
 196                 snprintf(bufout, sizeof(bufout), "-!- %s(%s) has left %s",
 197                                 argv[Tnick], argv[Tuser], argv[Tchan]);
 198         } else if(!strncmp("MODE", argv[Tcmd], 5))
 199                 snprintf(bufout, sizeof(bufout), "-!- %s changed mode/%s -> %s %s",
 200                                 argv[Tnick], argv[Tcmd + 1],
 201                                 argv[Tcmd + 2], argv[Tcmd + 3]);
 202         else if(!strncmp("QUIT", argv[Tcmd], 5))
 203                 snprintf(bufout, sizeof(bufout), "-!- %s(%s) has quit \"%s\"",
 204                                 argv[Tnick], argv[Tuser],
 205                                 argv[Ttext] ? argv[Ttext] : "");
 206         else if(!strncmp("NICK", argv[Tcmd], 5))
 207                 snprintf(bufout, sizeof(bufout), "-!- %s changed nick to %s",
 208                                 argv[Tnick], argv[Ttext]);
 209         else if(!strncmp("TOPIC", argv[Tcmd], 6))
 210                 snprintf(bufout, sizeof(bufout), "-!- %s changed topic to \"%s\"",
 211                                 argv[Tnick], argv[Ttext] ? argv[Ttext] : "");
 212         else if(!strncmp("KICK", argv[Tcmd], 5))
 213                 snprintf(bufout, sizeof(bufout), "-!- %s kicked %s (\"%s\")",
 214                                 argv[Tnick], argv[Targ],
 215                                 argv[Ttext] ? argv[Ttext] : "");
 216         else if(!strncmp("NOTICE", argv[Tcmd], 7))
 217                 snprintf(bufout, sizeof(bufout), "-!- \"%s\")",
 218                                 argv[Ttext] ? argv[Ttext] : "");
 219         else if(!strncmp("PRIVMSG", argv[Tcmd], 8))
 220                 snprintf(bufout, sizeof(bufout), "<%s> %s",
 221                                 argv[Tnick], argv[Ttext] ? argv[Ttext] : "");
 222         if(!argv[Tchan] || !strncmp(argv[Tchan], nick, strlen(nick)))
 223                 pout(argv[Tnick], bufout);
 224         else
 225                 pout(argv[Tchan], bufout);
 226 }
 227
 228 int
 229 main(int argc, char *argv[])
 230 {
 231         int i;
 232         struct timeval tv;
 233         struct hostent *hp;
 234         static struct sockaddr_in addr;  /* initially filled with 0's */
 235         char ping[256];
 236         fd_set rd;
 237
 238         nick = fullname = getenv("USER");
 239         for(i = 1; (i < argc) && (argv[i][0] == '-'); i++) {
 240                 switch (argv[i][1]) {
 241                 default:
 242                         fputs("usage: sic [-s server] [-p port] [-n nick]"
 243                                         " [-k keyword] [-f fullname] [-v]\n", stderr);
 244                         exit(EXIT_FAILURE);
 245                         break;
 246                 case 's':
 247                         server = argv[++i];
 248                         break;
 249                 case 'p':
 250                         port = (unsigned short)atoi(argv[++i]);
 251                         break;
 252                 case 'n':
 253                         nick = argv[++i];
 254                         break;
 255                 case 'k':
 256                         password = argv[++i];
 257                         break;
 258                 case 'f':
 259                         fullname = argv[++i];
 260                         break;
 261                 case 'v':
 262                         fputs("sic-"VERSION", (C)opyright MMVI Anselm R. Garbe\n", stdout);
 263                         exit(EXIT_SUCCESS);
 264                         break;
 265                 }
 266         }
 267
 268         /* init */
 269         if((srv = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
 270                 fprintf(stderr, "sic: cannot connect server '%s'\n", server);
 271                 exit(EXIT_FAILURE);
 272         }
 273         if (NULL == (hp = gethostbyname(server))) {
 274                 fprintf(stderr, "sic: cannot resolve hostname '%s'\n", server);
 275                 exit(EXIT_FAILURE);
 276         }
 277         addr.sin_family = AF_INET;
 278         addr.sin_port = htons(port);
 279         memcpy(&addr.sin_addr, hp->h_addr, hp->h_length);
 280         if(connect(srv, (struct sockaddr *) &addr, sizeof(struct sockaddr_in))) {
 281                 close(srv);
 282                 fprintf(stderr, "sic: cannot connect server '%s'\n", server);
 283                 exit(EXIT_FAILURE);
 284         }
 285
 286         /* login */
 287         if(password)
 288                 snprintf(bufout, sizeof(bufout),
 289                                 "PASS %s\r\nNICK %s\r\nUSER %s localhost %s :%s\r\n",
 290                                 password, nick, nick, server, fullname);
 291         else
 292                 snprintf(bufout, sizeof(bufout), "NICK %s\r\nUSER %s localhost %s :%s\r\n",
 293                                  nick, nick, server, fullname);
 294         write(srv, bufout, strlen(bufout));
 295
 296         snprintf(ping, sizeof(ping), "PING %s\r\n", server);
 297         channel[0] = 0;
 298         setbuf(stdout, NULL); /* unbuffered stdout */
 299         for(;;) {
 300                 FD_ZERO(&rd);
 301                 FD_SET(0, &rd);
 302                 FD_SET(srv, &rd);
 303                 tv.tv_sec = 120;
 304                 tv.tv_usec = 0;
 305                 i = select(srv + 1, &rd, 0, 0, &tv);
 306                 if(i < 0) {
 307                         if(errno == EINTR)
 308                                 continue;
 309                         perror("sic: error on select()");
 310                         exit(EXIT_FAILURE);
 311                 } else if(i == 0) {
 312                         if(time(NULL) - trespond >= PINGTIMEOUT) {
 313                                 pout(server, "-!- sic shutting down: parseing timeout");
 314                                 exit(EXIT_FAILURE);
 315                         }
 316                         write(srv, ping, strlen(ping));
 317                         continue;
 318                 }
 319                 if(FD_ISSET(srv, &rd)) {
 320                         if(getline(srv, sizeof(bufin), bufin) == -1) {
 321                                 perror("sic: remote server closed connection");
 322                                 exit(EXIT_FAILURE);
 323                         }
 324                         parsesrv(bufin);
 325                         trespond = time(NULL);
 326                 }
 327                 if(FD_ISSET(0, &rd)) {
 328                         if(getline(0, sizeof(bufin), bufin) == -1) {
 329                                 perror("sic: broken pipe");
 330                                 exit(EXIT_FAILURE);
 331                         }
 332                         parsein(bufin);
 333                 }
 334         }
 335
 336         return 0;
 337 }