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 *host = "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         pout("debug", msg);
 105         if(msg[0] != ':')
 106                 return; /* don't handle prefix-less server commands */
 107         if(!(p = strchr(msg, ' ')))
 108                 return;
 109         usr = &msg[1];
 110         *p = 0;
 111         cmd = ++p;
 112         if((p = strchr(usr, '!')))
 113                 *p = 0;
 114         /* remove CRLFs */
 115         if(!(p = strchr(cmd, ':')))
 116                 return;
 117         *p = 0;
 118         txt = ++p;
 119         for(p = txt; *p; p++)
 120                 if(*p == '\r' || *p == '\n')
 121                         *p = 0;
 122         if(!strncmp("PONG", cmd, 4))
 123                 return;
 124         if(!strncmp("PRIVMSG", cmd, 7) && txt) {
 125                 if(!(p = strchr(cmd, ' ')))
 126                         return;
 127                 *p = 0;
 128                 chan = ++p;
 129                 for(; *p && *p != ' '; p++);
 130                 *p = 0;
 131                 snprintf(bufout, sizeof bufout, "<%s> %s", usr, txt);
 132                 pout(chan, bufout);
 133         }
 134         else if(!strncmp("PING", cmd, 4) && txt) {
 135                 snprintf(bufout, sizeof bufout, "PONG %s\r\n", txt);
 136                 write(srv, bufout, strlen(bufout));
 137         }
 138         else {
 139                 snprintf(bufout, sizeof bufout, "-!- %s: %s", cmd, txt ? txt : "");
 140                 pout(usr, bufout);
 141         }
 142 }
 143
 144 int
 145 main(int argc, char *argv[]) {
 146         int i;
 147         struct timeval tv;
 148         struct hostent *hp;
 149         static struct sockaddr_in addr;  /* initially filled with 0's */
 150         char ping[256];
 151         fd_set rd;
 152
 153         nick = fullname = getenv("USER");
 154         for(i = 1; i < argc; i++)
 155                 if(!strncmp(argv[i], "-h", 3)) {
 156                         if(++i < argc) host = argv[i];
 157                 }
 158                 else if(!strncmp(argv[i], "-p", 3)) {
 159                         if(++i < argc) port = (unsigned short)atoi(argv[i]);
 160                 }
 161                 else if(!strncmp(argv[i], "-n", 3)) {
 162                         if(++i < argc) nick = argv[i];
 163                 }
 164                 else if(!strncmp(argv[i], "-k", 3)) {
 165                         if(++i < argc) password = argv[i];
 166                 }
 167                 else if(!strncmp(argv[i], "-f", 3)) {
 168                         if(++i < argc) fullname = argv[i];
 169                 }
 170                 else if(!strncmp(argv[i], "-v", 3)) {
 171                         fputs("sic-"VERSION", (C)opyright MMVI Anselm R. Garbe\n", stdout);
 172                         exit(EXIT_SUCCESS);
 173                 }
 174                 else {
 175                         fputs("usage: sic [-h host] [-p port] [-n nick]"
 176                                         " [-k keyword] [-f fullname] [-v]\n", stderr);
 177                         exit(EXIT_FAILURE);
 178                 }
 179
 180         /* init */
 181         if((srv = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
 182                 fprintf(stderr, "sic: cannot connect host '%s'\n", host);
 183                 exit(EXIT_FAILURE);
 184         }
 185         if (NULL == (hp = gethostbyname(host))) {
 186                 fprintf(stderr, "sic: cannot resolve hostname '%s'\n", host);
 187                 exit(EXIT_FAILURE);
 188         }
 189         addr.sin_family = AF_INET;
 190         addr.sin_port = htons(port);
 191         memcpy(&addr.sin_addr, hp->h_addr, hp->h_length);
 192         if(connect(srv, (struct sockaddr *) &addr, sizeof(struct sockaddr_in))) {
 193                 close(srv);
 194                 fprintf(stderr, "sic: cannot connect host '%s'\n", host);
 195                 exit(EXIT_FAILURE);
 196         }
 197         /* login */
 198         if(password)
 199                 snprintf(bufout, sizeof bufout,
 200                                 "PASS %s\r\nNICK %s\r\nUSER %s localhost %s :%s\r\n",
 201                                 password, nick, nick, host, fullname);
 202         else
 203                 snprintf(bufout, sizeof bufout, "NICK %s\r\nUSER %s localhost %s :%s\r\n",
 204                                  nick, nick, host, fullname);
 205         write(srv, bufout, strlen(bufout));
 206         snprintf(ping, sizeof ping, "PING %s\r\n", host);
 207         channel[0] = 0;
 208         setbuf(stdout, NULL); /* unbuffered stdout */
 209
 210         for(;;) { /* main loop */
 211                 FD_ZERO(&rd);
 212                 FD_SET(0, &rd);
 213                 FD_SET(srv, &rd);
 214                 tv.tv_sec = 120;
 215                 tv.tv_usec = 0;
 216                 i = select(srv + 1, &rd, 0, 0, &tv);
 217                 if(i < 0) {
 218                         if(errno == EINTR)
 219                                 continue;
 220                         perror("sic: error on select()");
 221                         exit(EXIT_FAILURE);
 222                 } else if(i == 0) {
 223                         if(time(NULL) - trespond >= PINGTIMEOUT) {
 224                                 pout(host, "-!- sic shutting down: parse timeout");
 225                                 exit(EXIT_FAILURE);
 226                         }
 227                         write(srv, ping, strlen(ping));
 228                         continue;
 229                 }
 230                 if(FD_ISSET(srv, &rd)) {
 231                         if(getline(srv, sizeof bufin, bufin) == -1) {
 232                                 perror("sic: remote host closed connection");
 233                                 exit(EXIT_FAILURE);
 234                         }
 235                         parsesrv(bufin);
 236                         trespond = time(NULL);
 237                 }
 238                 if(FD_ISSET(0, &rd)) {
 239                         if(getline(0, sizeof bufin, bufin) == -1) {
 240                                 perror("sic: broken pipe");
 241                                 exit(EXIT_FAILURE);
 242                         }
 243                         parsein(bufin);
 244                 }
 245         }
 246         return 0;
 247 }