sic.c

   1 /* See LICENSE file for license details. */
   2 #include <errno.h>
   3 #include <netdb.h>
   4 #include <netinet/in.h>
   5 #include <stdarg.h>
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <string.h>
   9 #include <time.h>
  10 #include <unistd.h>
  11 #include <sys/socket.h>
  12 #include <sys/time.h>
  13
  14 #define PINGTIMEOUT 300
  15 #define MAXMSG      4096
  16
  17 static void die(const char *errstr, ...);
  18 static void printl(char *channel, char *msg);
  19 static void privmsg(char *channel, char *msg);
  20 static void parsein(char *msg);
  21 static void parsesrv(char *msg);
  22 static int readl(int fd, unsigned int len, char *buf);
  23
  24 static char *host = "irc6.oftc.net";
  25 static char *port = "6667";
  26 static char *password = NULL;
  27 static char nick[32];
  28
  29 static char bufin[MAXMSG], bufout[MAXMSG];
  30 static char channel[256];
  31 static int srv;
  32 static time_t trespond;
  33
  34 void
  35 die(const char *errstr, ...) {
  36         va_list ap;
  37
  38         va_start(ap, errstr);
  39         vfprintf(stderr, errstr, ap);
  40         va_end(ap);
  41         exit(EXIT_FAILURE);
  42 }
  43
  44 void
  45 printl(char *channel, char *msg) {
  46         static char timestr[18];
  47         time_t t = time(0);
  48
  49         strftime(timestr, sizeof timestr, "%D %R", localtime(&t));
  50         fprintf(stdout, "%-12.12s: %s %s\n", channel, timestr, msg);
  51 }
  52
  53 void
  54 privmsg(char *channel, char *msg) {
  55         if(channel[0] == 0)
  56                 return;
  57         snprintf(bufout, sizeof bufout, "<%s> %s", nick, msg);
  58         printl(channel, bufout);
  59         snprintf(bufout, sizeof bufout, "PRIVMSG %s :%s\r\n", channel, msg);
  60         write(srv, bufout, strlen(bufout));
  61 }
  62
  63 void
  64 parsein(char *msg) {
  65         char *p;
  66
  67         if(msg[0] == 0)
  68                 return;
  69         if(msg[0] != ':') {
  70                 privmsg(channel, msg);
  71                 return;
  72         }
  73         if(!strncmp(msg + 1, "j ", 2) && (msg[3] == '#'))
  74                 snprintf(bufout, sizeof bufout, "JOIN %s\r\n", msg + 3);
  75         else if(!strncmp(msg + 1, "l ", 2))
  76                 snprintf(bufout, sizeof bufout, "PART %s :sic - 250 LOC are too much!\r\n", msg + 3);
  77         else if(!strncmp(msg + 1, "m ", 2)) {
  78                 if((p = strchr(msg + 3, ' ')))
  79                         *(p++) = 0;
  80                 privmsg(msg + 3, p);
  81                 return;
  82         }
  83         else if(!strncmp(msg + 1, "s ", 2)) {
  84                 strncpy(channel, msg + 3, sizeof channel);
  85                 return;
  86         }
  87         else
  88                 snprintf(bufout, sizeof bufout, "%s\r\n", msg + 1);
  89         write(srv, bufout, strlen(bufout));
  90 }
  91
  92 void
  93 parsesrv(char *msg) {
  94         char *chan, *cmd, *p, *txt, *usr;
  95
  96         txt = NULL;
  97         usr = host;
  98         if(!msg || !(*msg))
  99                 return;
 100         if(msg[0] != ':')
 101                 cmd = msg;
 102         else {
 103                 if(!(p = strchr(msg, ' ')))
 104                         return;
 105                 *p = 0;
 106                 usr = msg + 1;
 107                 cmd = ++p;
 108                 if((p = strchr(usr, '!')))
 109                         *p = 0;
 110         }
 111         for(p = cmd; *p; p++) /* remove CRLFs */
 112                 if(*p == '\r' || *p == '\n')
 113                         *p = 0;
 114         if((p = strchr(cmd, ':'))) {
 115                 *p = 0;
 116                 txt = ++p;
 117         }
 118         if(!strncmp("PONG", cmd, 4))
 119                 return;
 120         if(!strncmp("PRIVMSG", cmd, 7) && txt) {
 121                 if(!(p = strchr(cmd, ' ')))
 122                         return;
 123                 *p = 0;
 124                 chan = ++p;
 125                 for(; *p && *p != ' '; p++);
 126                 *p = 0;
 127                 snprintf(bufout, sizeof bufout, "<%s> %s", usr, txt);
 128                 printl(chan, bufout);
 129         }
 130         else if(!strncmp("PING", cmd, 4) && txt) {
 131                 snprintf(bufout, sizeof bufout, "PONG %s\r\n", txt);
 132                 write(srv, bufout, strlen(bufout));
 133         }
 134         else {
 135                 snprintf(bufout, sizeof bufout, ">< %s: %s", cmd, txt ? txt : "");
 136                 printl(usr, bufout);
 137                 if(!strncmp("NICK", cmd, 4) && !strncmp(usr, nick, sizeof nick) && txt)
 138                         strncpy(nick, txt, sizeof nick);
 139         }
 140 }
 141
 142 int
 143 readl(int fd, unsigned int len, char *buf) {
 144         unsigned int i = 0;
 145         char c;
 146
 147         do {
 148                 if(read(fd, &c, sizeof(char)) != sizeof(char))
 149                         return -1;
 150                 buf[i++] = c;
 151         }
 152         while(c != '\n' && i < len);
 153         buf[i - 1] = 0;
 154         return 0;
 155 }
 156
 157
 158 int
 159 main(int argc, char *argv[]) {
 160         int i;
 161         struct timeval tv;
 162         static struct addrinfo hints, *res, *r;
 163         char ping[256];
 164         fd_set rd;
 165
 166         strncpy(nick, getenv("USER"), sizeof nick);
 167         for(i = 1; i < argc; i++)
 168                 if(!strncmp(argv[i], "-h", 3)) {
 169                         if(++i < argc) host = argv[i];
 170                 }
 171                 else if(!strncmp(argv[i], "-p", 3)) {
 172                         if(++i < argc) port = argv[i];
 173                 }
 174                 else if(!strncmp(argv[i], "-n", 3)) {
 175                         if(++i < argc) strncpy(nick, argv[i], sizeof nick);
 176                 }
 177                 else if(!strncmp(argv[i], "-k", 3)) {
 178                         if(++i < argc) password = argv[i];
 179                 }
 180                 else if(!strncmp(argv[i], "-v", 3))
 181                         die("sic-"VERSION", © 2005-2009 sic engineers\n");
 182                 else
 183                         die("usage: sic [-h host] [-p port] [-n nick] [-k keyword] [-v]\n");
 184
 185         /* init */
 186         memset(&hints, 0, sizeof hints);
 187         hints.ai_family = AF_UNSPEC;
 188         hints.ai_socktype = SOCK_STREAM;
 189         if(getaddrinfo(host, port, &hints, &res) != 0)
 190                 die("error: cannot resolve hostname '%s'\n", host);
 191         for(ri = res; r; r = r->ai_next) {
 192                 if((srv = socket(r->ai_family, r->ai_socktype, r->ai_protocol)) == -1)
 193                         continue;
 194                 if(connect(srv, r->ai_addr, r->ai_addrlen) == 0)
 195                         break;
 196                 close(srv);
 197         }
 198         freeaddrinfo(res);
 199         if(!r)
 200                 die("error: cannot connect to host '%s'\n", host);
 201
 202         /* login */
 203         if(password)
 204                 snprintf(bufout, sizeof bufout,
 205                         "PASS %s\r\nNICK %s\r\nUSER %s localhost %s :%s\r\n",
 206                         password, nick, nick, host, nick);
 207         else
 208                 snprintf(bufout, sizeof bufout, "NICK %s\r\nUSER %s localhost %s :%s\r\n",
 209                          nick, nick, host, nick);
 210         write(srv, bufout, strlen(bufout));
 211         snprintf(ping, sizeof ping, "PING %s\r\n", host);
 212         channel[0] = 0;
 213         setbuf(stdout, NULL); /* unbuffered stdout */
 214
 215         for(;;) { /* main loop */
 216                 FD_ZERO(&rd);
 217                 FD_SET(0, &rd);
 218                 FD_SET(srv, &rd);
 219                 tv.tv_sec = 120;
 220                 tv.tv_usec = 0;
 221                 i = select(srv + 1, &rd, 0, 0, &tv);
 222                 if(i < 0) {
 223                         if(errno == EINTR)
 224                                 continue;
 225                         die("error: error on select()\n");
 226                 }
 227                 else if(i == 0) {
 228                         if(time(NULL) - trespond >= PINGTIMEOUT)
 229                                 die("error: sic shutting down: parse timeout\n");
 230                         write(srv, ping, strlen(ping));
 231                         continue;
 232                 }
 233                 if(FD_ISSET(srv, &rd)) {
 234                         if(readl(srv, sizeof bufin, bufin) == -1)
 235                                 die("error: remote host closed connection\n");
 236                         parsesrv(bufin);
 237                         trespond = time(NULL);
 238                 }
 239                 if(FD_ISSET(0, &rd)) {
 240                         if(readl(0, sizeof bufin, bufin) == -1)
 241                                 die("error: broken pipe\n");
 242                         parsein(bufin);
 243                 }
 244         }
 245         return 0;
 246 }