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, "%F %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                 if (!(p = strchr(msg, ' ')))
 146                         return;
 147                 *p = 0;
 148                 for(++p; *p == ' '; p++);
 149                 cmd = p;
 150                 argv[Tnick] = &msg[1];
 151                 if((p = strchr(msg, '!'))) {
 152                         *p = 0;
 153                         argv[Tuser] = ++p;
 154                 }
 155         } else
 156                 cmd = msg;
 157         /* remove CRLFs */
 158         for(p = cmd; p && *p != 0; p++)
 159                 if(*p == '\r' || *p == '\n')
 160                         *p = 0;
 161         if((p = strchr(cmd, ':'))) {
 162                 *p = 0;
 163                 argv[Ttext] = ++p;
 164         }
 165         tokenize(&argv[Tcmd], Tlast - Tcmd, cmd, ' ');
 166         if(!argv[Tcmd] || !strncmp("PONG", argv[Tcmd], 5))
 167                 return;
 168         else if(!strncmp("PING", argv[Tcmd], 5)) {
 169                 snprintf(bufout, sizeof bufout, "PONG %s\r\n", argv[Ttext]);
 170                 write(srv, bufout, strlen(bufout));
 171                 return;
 172         }
 173         else if(!argv[Tnick] || !argv[Tuser]) { /* server command */
 174                 snprintf(bufout, sizeof bufout, "%s", argv[Ttext] ? argv[Ttext] : "");
 175                 pout(server, bufout);
 176                 return;
 177         }
 178         else if(!strncmp("ERROR", argv[Tcmd], 6))
 179                 snprintf(bufout, sizeof bufout, "-!- error %s",
 180                                 argv[Ttext] ? argv[Ttext] : "unknown");
 181         else if(!strncmp("JOIN", argv[Tcmd], 5)) {
 182                 if(argv[Ttext]!=NULL){
 183                         p = strchr(argv[Ttext], ' ');
 184                 if(p)
 185                         *p = 0;
 186                 }
 187                 argv[Tchan] = argv[Ttext];
 188                 snprintf(bufout, sizeof bufout, "-!- %s(%s) has joined %s",
 189                                 argv[Tnick], argv[Tuser], argv[Ttext]);
 190         }
 191         else if(!strncmp("PART", argv[Tcmd], 5)) {
 192                 snprintf(bufout, sizeof bufout, "-!- %s(%s) has left %s",
 193                                 argv[Tnick], argv[Tuser], argv[Tchan]);
 194         }
 195         else if(!strncmp("MODE", argv[Tcmd], 5))
 196                 snprintf(bufout, sizeof bufout, "-!- %s changed mode/%s -> %s %s",
 197                                 argv[Tnick], argv[Tcmd + 1] ? argv[Tcmd + 1] : "",
 198                                 argv[Tcmd + 2] ? argv[Tcmd + 2] : "",
 199                                 argv[Tcmd + 3] ? argv[Tcmd + 3] : "");
 200         else if(!strncmp("QUIT", argv[Tcmd], 5))
 201                 snprintf(bufout, sizeof bufout, "-!- %s(%s) has quit \"%s\"",
 202                                 argv[Tnick], argv[Tuser],
 203                                 argv[Ttext] ? argv[Ttext] : "");
 204         else if(!strncmp("NICK", argv[Tcmd], 5))
 205                 snprintf(bufout, sizeof bufout, "-!- %s changed nick to %s",
 206                                 argv[Tnick], argv[Ttext]);
 207         else if(!strncmp("TOPIC", argv[Tcmd], 6))
 208                 snprintf(bufout, sizeof bufout, "-!- %s changed topic to \"%s\"",
 209                                 argv[Tnick], argv[Ttext] ? argv[Ttext] : "");
 210         else if(!strncmp("KICK", argv[Tcmd], 5))
 211                 snprintf(bufout, sizeof bufout, "-!- %s kicked %s (\"%s\")",
 212                                 argv[Tnick], argv[Targ],
 213                                 argv[Ttext] ? argv[Ttext] : "");
 214         else if(!strncmp("NOTICE", argv[Tcmd], 7))
 215                 snprintf(bufout, sizeof bufout, "-!- \"%s\")",
 216                                 argv[Ttext] ? argv[Ttext] : "");
 217         else if(!strncmp("PRIVMSG", argv[Tcmd], 8))
 218                 snprintf(bufout, sizeof bufout, "<%s> %s",
 219                                 argv[Tnick], argv[Ttext] ? argv[Ttext] : "");
 220         if(!argv[Tchan] || !strncmp(argv[Tchan], nick, strlen(nick)))
 221                 pout(argv[Tnick], bufout);
 222         else
 223                 pout(argv[Tchan], bufout);
 224 }
 225
 226 int
 227 main(int argc, char *argv[]) {
 228         int i;
 229         struct timeval tv;
 230         struct hostent *hp;
 231         static struct sockaddr_in addr;  /* initially filled with 0's */
 232         char ping[256];
 233         fd_set rd;
 234
 235         nick = fullname = getenv("USER");
 236         for(i = 1; i < argc; i++)
 237                 if(!strncmp(argv[i], "-s", 3)) {
 238                         if(++i < argc) server = argv[i];
 239                 }
 240                 else if(!strncmp(argv[i], "-p", 3)) {
 241                         if(++i < argc) port = (unsigned short)atoi(argv[i]);
 242                 }
 243                 else if(!strncmp(argv[i], "-n", 3)) {
 244                         if(++i < argc) nick = argv[i];
 245                 }
 246                 else if(!strncmp(argv[i], "-k", 3)) {
 247                         if(++i < argc) password = argv[i];
 248                 }
 249                 else if(!strncmp(argv[i], "-f", 3)) {
 250                         if(++i < argc) fullname = argv[i];
 251                 }
 252                 else if(!strncmp(argv[i], "-v", 3)) {
 253                         fputs("sic-"VERSION", (C)opyright MMVI Anselm R. Garbe\n", stdout);
 254                         exit(EXIT_SUCCESS);
 255                 }
 256                 else {
 257                         fputs("usage: sic [-s server] [-p port] [-n nick]"
 258                                         " [-k keyword] [-f fullname] [-v]\n", stderr);
 259                         exit(EXIT_FAILURE);
 260                 }
 261
 262         /* init */
 263         if((srv = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
 264                 fprintf(stderr, "sic: cannot connect server '%s'\n", server);
 265                 exit(EXIT_FAILURE);
 266         }
 267         if (NULL == (hp = gethostbyname(server))) {
 268                 fprintf(stderr, "sic: cannot resolve hostname '%s'\n", server);
 269                 exit(EXIT_FAILURE);
 270         }
 271         addr.sin_family = AF_INET;
 272         addr.sin_port = htons(port);
 273         memcpy(&addr.sin_addr, hp->h_addr, hp->h_length);
 274         if(connect(srv, (struct sockaddr *) &addr, sizeof(struct sockaddr_in))) {
 275                 close(srv);
 276                 fprintf(stderr, "sic: cannot connect server '%s'\n", server);
 277                 exit(EXIT_FAILURE);
 278         }
 279         /* login */
 280         if(password)
 281                 snprintf(bufout, sizeof bufout,
 282                                 "PASS %s\r\nNICK %s\r\nUSER %s localhost %s :%s\r\n",
 283                                 password, nick, nick, server, fullname);
 284         else
 285                 snprintf(bufout, sizeof bufout, "NICK %s\r\nUSER %s localhost %s :%s\r\n",
 286                                  nick, nick, server, fullname);
 287         write(srv, bufout, strlen(bufout));
 288         snprintf(ping, sizeof ping, "PING %s\r\n", server);
 289         channel[0] = 0;
 290         setbuf(stdout, NULL); /* unbuffered stdout */
 291
 292         for(;;) { /* main loop */
 293                 FD_ZERO(&rd);
 294                 FD_SET(0, &rd);
 295                 FD_SET(srv, &rd);
 296                 tv.tv_sec = 120;
 297                 tv.tv_usec = 0;
 298                 i = select(srv + 1, &rd, 0, 0, &tv);
 299                 if(i < 0) {
 300                         if(errno == EINTR)
 301                                 continue;
 302                         perror("sic: error on select()");
 303                         exit(EXIT_FAILURE);
 304                 } else if(i == 0) {
 305                         if(time(NULL) - trespond >= PINGTIMEOUT) {
 306                                 pout(server, "-!- sic shutting down: parse timeout");
 307                                 exit(EXIT_FAILURE);
 308                         }
 309                         write(srv, ping, strlen(ping));
 310                         continue;
 311                 }
 312                 if(FD_ISSET(srv, &rd)) {
 313                         if(getline(srv, sizeof bufin, bufin) == -1) {
 314                                 perror("sic: remote server closed connection");
 315                                 exit(EXIT_FAILURE);
 316                         }
 317                         parsesrv(bufin);
 318                         trespond = time(NULL);
 319                 }
 320                 if(FD_ISSET(0, &rd)) {
 321                         if(getline(0, sizeof bufin, bufin) == -1) {
 322                                 perror("sic: broken pipe");
 323                                 exit(EXIT_FAILURE);
 324                         }
 325                         parsein(bufin);
 326                 }
 327         }
 328         return 0;
 329 }