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