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 static char *server = "irc.oftc.net";
  20 static unsigned short port = 6667;
  21 static char *nick = NULL;
  22 static char *fullname = NULL;
  23 static char *password = NULL;
  24
  25 static char bufin[MAXMSG], bufout[MAXMSG];
  26 static char channel[256];
  27 static int srv;
  28 static time_t trespond;
  29
  30 static int
  31 getline(int fd, unsigned int len, char *buf) {
  32         unsigned int i = 0;
  33         char c;
  34
  35         do {
  36                 if(read(fd, &c, sizeof(char)) != sizeof(char))
  37                         return -1;
  38                 buf[i++] = c;
  39         }
  40         while(c != '\n' && i < len);
  41         buf[i - 1] = 0;
  42         return 0;
  43 }
  44
  45 static void
  46 pout(char *channel, char *msg) {
  47         static char timestr[18];
  48         time_t t = time(0);
  49
  50         strftime(timestr, sizeof timestr, "%F %R", localtime(&t));
  51         fprintf(stdout, "%-8.8s: %s %s\n", channel, timestr, msg);
  52 }
  53
  54 static void
  55 privmsg(char *channel, char *msg) {
  56         if(channel[0] == 0)
  57                 return;
  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 - 250 LOC are too much!\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 void
  99 parsesrv(char *msg) {
 100         char *chan, *cmd, *p, *txt, *usr;
 101
 102         if(!msg || !(*msg))
 103                 return;
 104         if(msg[0] == ':') { /* check prefix */
 105                 if(!(p = strchr(msg, ' ')))
 106                         return;
 107                 *p = 0;
 108                 usr = &msg[1];
 109                 cmd = ++p;
 110                 if((p = strchr(usr, '!')))
 111                         *p = 0;
 112         } else
 113                 cmd = msg;
 114         /* remove CRLFs */
 115         for(p = cmd; *p; p++)
 116                 if(*p == '\r' || *p == '\n')
 117                         *p = 0;
 118         if(!strncmp("PONG", cmd, 4))
 119                 return;
 120         if(!strncmp("PRIVMSG", cmd, 7) || !strncmp("PING", cmd, 4)) {
 121                 if(!(p = strchr(cmd, ' ')))
 122                         return;
 123                 *p = 0;
 124                 chan = ++p;
 125                 for(; *p && *p != ' '; p++);
 126                 *p = 0;
 127                 if(!(p = strchr(++p, ':')))
 128                         return;
 129                 *p = 0;
 130                 txt = ++p;
 131                 if(!strncmp("PRIVMSG", cmd, 8) && chan && txt) {
 132                         snprintf(bufout, sizeof bufout, "<%s> %s", usr, txt);
 133                         pout(chan, bufout);
 134                 }
 135                 else if(!strncmp("PING", cmd, 5) && txt) {
 136                         snprintf(bufout, sizeof bufout, "PONG %s\r\n", txt);
 137                         write(srv, bufout, strlen(bufout));
 138                 }
 139                 return;
 140         }
 141         snprintf(bufout, sizeof bufout, "-!- %s", cmd);
 142         pout(server, bufout);
 143 }
 144
 145 int
 146 main(int argc, char *argv[]) {
 147         int i;
 148         struct timeval tv;
 149         struct hostent *hp;
 150         static struct sockaddr_in addr;  /* initially filled with 0's */
 151         char ping[256];
 152         fd_set rd;
 153
 154         nick = fullname = getenv("USER");
 155         for(i = 1; i < argc; i++)
 156                 if(!strncmp(argv[i], "-s", 3)) {
 157                         if(++i < argc) server = argv[i];
 158                 }
 159                 else if(!strncmp(argv[i], "-p", 3)) {
 160                         if(++i < argc) port = (unsigned short)atoi(argv[i]);
 161                 }
 162                 else if(!strncmp(argv[i], "-n", 3)) {
 163                         if(++i < argc) nick = argv[i];
 164                 }
 165                 else if(!strncmp(argv[i], "-k", 3)) {
 166                         if(++i < argc) password = argv[i];
 167                 }
 168                 else if(!strncmp(argv[i], "-f", 3)) {
 169                         if(++i < argc) fullname = argv[i];
 170                 }
 171                 else if(!strncmp(argv[i], "-v", 3)) {
 172                         fputs("sic-"VERSION", (C)opyright MMVI Anselm R. Garbe\n", stdout);
 173                         exit(EXIT_SUCCESS);
 174                 }
 175                 else {
 176                         fputs("usage: sic [-s server] [-p port] [-n nick]"
 177                                         " [-k keyword] [-f fullname] [-v]\n", stderr);
 178                         exit(EXIT_FAILURE);
 179                 }
 180
 181         /* init */
 182         if((srv = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
 183                 fprintf(stderr, "sic: cannot connect server '%s'\n", server);
 184                 exit(EXIT_FAILURE);
 185         }
 186         if (NULL == (hp = gethostbyname(server))) {
 187                 fprintf(stderr, "sic: cannot resolve hostname '%s'\n", server);
 188                 exit(EXIT_FAILURE);
 189         }
 190         addr.sin_family = AF_INET;
 191         addr.sin_port = htons(port);
 192         memcpy(&addr.sin_addr, hp->h_addr, hp->h_length);
 193         if(connect(srv, (struct sockaddr *) &addr, sizeof(struct sockaddr_in))) {
 194                 close(srv);
 195                 fprintf(stderr, "sic: cannot connect server '%s'\n", server);
 196                 exit(EXIT_FAILURE);
 197         }
 198         /* login */
 199         if(password)
 200                 snprintf(bufout, sizeof bufout,
 201                                 "PASS %s\r\nNICK %s\r\nUSER %s localhost %s :%s\r\n",
 202                                 password, nick, nick, server, fullname);
 203         else
 204                 snprintf(bufout, sizeof bufout, "NICK %s\r\nUSER %s localhost %s :%s\r\n",
 205                                  nick, nick, server, fullname);
 206         write(srv, bufout, strlen(bufout));
 207         snprintf(ping, sizeof ping, "PING %s\r\n", server);
 208         channel[0] = 0;
 209         setbuf(stdout, NULL); /* unbuffered stdout */
 210
 211         for(;;) { /* main loop */
 212                 FD_ZERO(&rd);
 213                 FD_SET(0, &rd);
 214                 FD_SET(srv, &rd);
 215                 tv.tv_sec = 120;
 216                 tv.tv_usec = 0;
 217                 i = select(srv + 1, &rd, 0, 0, &tv);
 218                 if(i < 0) {
 219                         if(errno == EINTR)
 220                                 continue;
 221                         perror("sic: error on select()");
 222                         exit(EXIT_FAILURE);
 223                 } else if(i == 0) {
 224                         if(time(NULL) - trespond >= PINGTIMEOUT) {
 225                                 pout(server, "-!- sic shutting down: parse timeout");
 226                                 exit(EXIT_FAILURE);
 227                         }
 228                         write(srv, ping, strlen(ping));
 229                         continue;
 230                 }
 231                 if(FD_ISSET(srv, &rd)) {
 232                         if(getline(srv, sizeof bufin, bufin) == -1) {
 233                                 perror("sic: remote server closed connection");
 234                                 exit(EXIT_FAILURE);
 235                         }
 236                         parsesrv(bufin);
 237                         trespond = time(NULL);
 238                 }
 239                 if(FD_ISSET(0, &rd)) {
 240                         if(getline(0, sizeof bufin, bufin) == -1) {
 241                                 perror("sic: broken pipe");
 242                                 exit(EXIT_FAILURE);
 243                         }
 244                         parsein(bufin);
 245                 }
 246         }
 247         return 0;
 248 }