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