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