sic.c

   1 /* (C)opyright MMV-MMVI Anselm R. Garbe <garbeam at gmail dot com>
   2  * (C)opyright MMV-MMVI Nico Golde <nico at ngolde dot de>
   3  * See LICENSE file for license details.
   4  */
   5 #include <errno.h>
   6 #include <netdb.h>
   7 #include <netinet/in.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <string.h>
  11 #include <time.h>
  12 #include <unistd.h>
  13 #include <sys/socket.h>
  14 #include <sys/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 unsigned short 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         unsigned int i = 0;
  35         char c;
  36
  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         static char timestr[18];
  50         time_t t = time(0);
  51
  52         strftime(timestr, sizeof(timestr), "%a %R", localtime(&t));
  53         fprintf(stdout, "%-8.8s: %s %s\n", channel, timestr, msg);
  54 }
  55
  56 static void
  57 privmsg(char *channel, char *msg) {
  58         snprintf(bufout, sizeof(bufout), "<%s> %s", nick, msg);
  59         pout(channel, bufout);
  60         snprintf(bufout, sizeof(bufout), "PRIVMSG %s :%s\r\n", channel, msg);
  61         write(srv, bufout, strlen(bufout));
  62 }
  63
  64 static void
  65 parsein(char *msg) {
  66         char *p;
  67
  68         if(msg[0] == 0)
  69                 return;
  70         if(msg[0] != '/') {
  71                 privmsg(channel, msg);
  72                 return;
  73         }
  74         if(!strncmp(msg + 1, "j ", 2) && (msg[3] == '#'))
  75                 snprintf(bufout, sizeof(bufout), "JOIN %s\r\n", &msg[3]);
  76         else if(!strncmp(msg + 1, "l ", 2))
  77                 snprintf(bufout, sizeof(bufout), "PART %s :sic\r\n", &msg[3]);
  78         else if(!strncmp(msg + 1, "m ", 2)) {
  79                 if((p = strchr(&msg[3], ' ')))
  80                         *(p++) = 0;
  81                 privmsg(&msg[3], p);
  82                 return;
  83         }
  84         else if(!strncmp(msg + 1, "s ", 2)) {
  85                 strncpy(channel, &msg[3], sizeof(channel));
  86                 return;
  87         }
  88         else if(!strncmp(msg + 1, "t ", 2)) {
  89                 if((p = strchr(&msg[3], ' '))
  90                         *(p++) = 0;
  91                 snprintf(bufout, sizeof(bufout), "TOPIC %s :%s\r\n", &msg[3], p);
  92         }
  93         else
  94                 snprintf(bufout, sizeof(bufout), "%s\r\n", &msg[1]);
  95         write(srv, bufout, strlen(bufout));
  96 }
  97
  98 static unsigned int
  99 tokenize(char **result, unsigned int reslen, char *str, char delim) {
 100         char *p, *n;
 101         unsigned int i = 0;
 102
 103         if(!str)
 104                 return 0;
 105         for(n = str; *n == delim; n++);
 106         p = n;
 107         for(i = 0; *n != 0;) {
 108                 if(i == reslen)
 109                         return i;
 110                 if(*n == delim) {
 111                         *n = 0;
 112                         if(strlen(p))
 113                                 result[i++] = p;
 114                         p = ++n;
 115                 } else
 116                         n++;
 117         }
 118         if((i < reslen) && (p < n) && strlen(p))
 119                 result[i++] = p;
 120         return i;       /* number of tokens */
 121 }
 122
 123 static void
 124 parsesrv(char *msg) {
 125         char *argv[Tlast], *cmd, *p;
 126         int i;
 127
 128         if(!msg || !(*msg))
 129                 return;
 130
 131         for(i = 0; i < Tlast; i++)
 132                 argv[i] = NULL;
 133
 134         /* <bufout>  ::= [':' <prefix> <SPACE> ] <command> <params> <crlf>
 135          * <prefix>   ::= <servername> | <nick> [ '!' <user> ] [ '@' <server> ]
 136          * <command>  ::= <letter> { <letter> } | <number> <number> <number>
 137          * <SPACE>    ::= ' ' { ' ' }
 138          * <params>   ::= <SPACE> [ ':' <trailing> | <middle> <params> ]
 139          * <middle>   ::= <Any *non-empty* sequence of octets not including SPACE
 140          * or NUL or CR or LF, the first of which may not be ':'>
 141          * <trailing> ::= <Any, possibly *empty*, sequence of octets not including NUL or CR or LF>
 142          * <crlf>     ::= CR LF
 143          */
 144         if(msg[0] == ':') { /* check prefix */
 145                 p = strchr(msg, ' ');
 146                 *p = 0;
 147                 for(++p; *p == ' '; p++);
 148                 cmd = p;
 149                 argv[Tnick] = &msg[1];
 150                 if((p = strchr(msg, '!'))) {
 151                         *p = 0;
 152                         argv[Tuser] = ++p;
 153                 }
 154         } else
 155                 cmd = msg;
 156         /* remove CRLFs */
 157         for(p = cmd; p && *p != 0; p++)
 158                 if(*p == '\r' || *p == '\n')
 159                         *p = 0;
 160         if((p = strchr(cmd, ':'))) {
 161                 *p = 0;
 162                 argv[Ttext] = ++p;
 163         }
 164         tokenize(&argv[Tcmd], Tlast - Tcmd, cmd, ' ');
 165         if(!strncmp("PONG", argv[Tcmd], 5))
 166                 return;
 167         else if(!strncmp("PING", argv[Tcmd], 5)) {
 168                 snprintf(bufout, sizeof(bufout), "PONG %s\r\n", argv[Ttext]);
 169                 write(srv, bufout, strlen(bufout));
 170                 return;
 171         }
 172         else if(!argv[Tnick] || !argv[Tuser]) { /* server command */
 173                 snprintf(bufout, sizeof(bufout), "%s", argv[Ttext] ? argv[Ttext] : "");
 174                 pout(server, bufout);
 175                 return;
 176         }
 177         else if(!strncmp("ERROR", argv[Tcmd], 6))
 178                 snprintf(bufout, sizeof(bufout), "-!- error %s",
 179                                 argv[Ttext] ? argv[Ttext] : "unknown");
 180         else if(!strncmp("JOIN", argv[Tcmd], 5)) {
 181                 if(argv[Ttext]!=NULL){
 182                         p = strchr(argv[Ttext], ' ');
 183                 if(p)
 184                         *p = 0;
 185                 }
 186                 argv[Tchan] = argv[Ttext];
 187                 snprintf(bufout, sizeof(bufout), "-!- %s(%s) has joined %s",
 188                                 argv[Tnick], argv[Tuser], argv[Ttext]);
 189         }
 190         else if(!strncmp("PART", argv[Tcmd], 5)) {
 191                 snprintf(bufout, sizeof(bufout), "-!- %s(%s) has left %s",
 192                                 argv[Tnick], argv[Tuser], argv[Tchan]);
 193         }
 194         else if(!strncmp("MODE", argv[Tcmd], 5))
 195                 snprintf(bufout, sizeof(bufout), "-!- %s changed mode/%s -> %s %s",
 196                                 argv[Tnick], argv[Tcmd + 1],
 197                                 argv[Tcmd + 2], argv[Tcmd + 3]);
 198         else if(!strncmp("QUIT", argv[Tcmd], 5))
 199                 snprintf(bufout, sizeof(bufout), "-!- %s(%s) has quit \"%s\"",
 200                                 argv[Tnick], argv[Tuser],
 201                                 argv[Ttext] ? argv[Ttext] : "");
 202         else if(!strncmp("NICK", argv[Tcmd], 5))
 203                 snprintf(bufout, sizeof(bufout), "-!- %s changed nick to %s",
 204                                 argv[Tnick], argv[Ttext]);
 205         else if(!strncmp("TOPIC", argv[Tcmd], 6))
 206                 snprintf(bufout, sizeof(bufout), "-!- %s changed topic to \"%s\"",
 207                                 argv[Tnick], argv[Ttext] ? argv[Ttext] : "");
 208         else if(!strncmp("KICK", argv[Tcmd], 5))
 209                 snprintf(bufout, sizeof(bufout), "-!- %s kicked %s (\"%s\")",
 210                                 argv[Tnick], argv[Targ],
 211                                 argv[Ttext] ? argv[Ttext] : "");
 212         else if(!strncmp("NOTICE", argv[Tcmd], 7))
 213                 snprintf(bufout, sizeof(bufout), "-!- \"%s\")",
 214                                 argv[Ttext] ? argv[Ttext] : "");
 215         else if(!strncmp("PRIVMSG", argv[Tcmd], 8))
 216                 snprintf(bufout, sizeof(bufout), "<%s> %s",
 217                                 argv[Tnick], argv[Ttext] ? argv[Ttext] : "");
 218         if(!argv[Tchan] || !strncmp(argv[Tchan], nick, strlen(nick)))
 219                 pout(argv[Tnick], bufout);
 220         else
 221                 pout(argv[Tchan], bufout);
 222 }
 223
 224 int
 225 main(int argc, char *argv[]) {
 226         int i;
 227         struct timeval tv;
 228         struct hostent *hp;
 229         static struct sockaddr_in addr;  /* initially filled with 0's */
 230         char ping[256];
 231         fd_set rd;
 232
 233         nick = fullname = getenv("USER");
 234         for(i = 1; i < argc; i++)
 235                 if(!strncmp(argv[i], "-s", 3))
 236                         server = argv[++i];
 237                 else if(!strncmp(argv[i], "-p", 3))
 238                         port = (unsigned short)atoi(argv[++i]);
 239                 else if(!strncmp(argv[i], "-n", 3))
 240                         nick = argv[++i];
 241                 else if(!strncmp(argv[i], "-k", 3))
 242                         password = argv[++i];
 243                 else if(!strncmp(argv[i], "-f", 3))
 244                         fullname = argv[++i];
 245                 else if(!strncmp(argv[i], "-v", 3)) {
 246                         fputs("sic-"VERSION", (C)opyright MMVI Anselm R. Garbe\n", stdout);
 247                         exit(EXIT_SUCCESS);
 248                 }
 249                 else {
 250                         fputs("usage: sic [-s server] [-p port] [-n nick]"
 251                                         " [-k keyword] [-f fullname] [-v]\n", stderr);
 252                         exit(EXIT_FAILURE);
 253                 }
 254
 255         /* init */
 256         if((srv = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
 257                 fprintf(stderr, "sic: cannot connect server '%s'\n", server);
 258                 exit(EXIT_FAILURE);
 259         }
 260         if (NULL == (hp = gethostbyname(server))) {
 261                 fprintf(stderr, "sic: cannot resolve hostname '%s'\n", server);
 262                 exit(EXIT_FAILURE);
 263         }
 264         addr.sin_family = AF_INET;
 265         addr.sin_port = htons(port);
 266         memcpy(&addr.sin_addr, hp->h_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", server);
 270                 exit(EXIT_FAILURE);
 271         }
 272         /* login */
 273         if(password)
 274                 snprintf(bufout, sizeof(bufout),
 275                                 "PASS %s\r\nNICK %s\r\nUSER %s localhost %s :%s\r\n",
 276                                 password, nick, nick, server, fullname);
 277         else
 278                 snprintf(bufout, sizeof(bufout), "NICK %s\r\nUSER %s localhost %s :%s\r\n",
 279                                  nick, nick, server, fullname);
 280         write(srv, bufout, strlen(bufout));
 281         snprintf(ping, sizeof(ping), "PING %s\r\n", server);
 282         channel[0] = 0;
 283         setbuf(stdout, NULL); /* unbuffered stdout */
 284
 285         for(;;) { /* main loop */
 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(server, "-!- 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 server 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         return 0;
 322 }