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Revision: 1.42
Committed: Mon May 28 21:22:26 2007 UTC (17 years ago) by root
Content type: text/plain
Branch: MAIN
Changes since 1.41: +19 -19 lines
Log Message:
update copyrights in socket/*.C

File Contents

# Content
1 /*
2 * This file is part of Crossfire TRT, the Multiplayer Online Role Playing Game.
3 *
4 * Copyright (©) 2005,2006,2007 Marc Alexander Lehmann / Robin Redeker / the Crossfire TRT team
5 * Copyright (©) 1992,2007 Frank Tore Johansen
6 *
7 * Crossfire TRT is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the Free
9 * Software Foundation; either version 2 of the License, or (at your option)
10 * any later version.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
14 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 * for more details.
16 *
17 * You should have received a copy of the GNU General Public License along
18 * with Crossfire TRT; if not, write to the Free Software Foundation, Inc. 51
19 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 *
21 * The authors can be reached via e-mail to <crossfire@schmorp.de>
22 */
23
24 /**
25 * \file
26 * Low-level socket-related functions.
27 *
28 * \date 2003-12-02
29 *
30 * Contains some base functions that both the client and server
31 * can use. As such, depending what we are being compiled for will
32 * determine what we can include. the client is designed have
33 * CFCLIENT defined as part of its compile flags.
34 */
35
36 using namespace std;
37
38 #include <global.h>
39 #include <sproto.h>
40 #include <cstdarg>
41
42 #ifdef __linux__
43 # include <sys/types.h>
44 # include <sys/socket.h>
45 # include <netinet/in.h>
46 # include <netinet/tcp.h>
47 #endif
48
49 // use a really low timeout, as it doesn't cost any bandwidth, and you can
50 // easily die in 20 seconds...
51 #define SOCKET_TIMEOUT1 10 * 1000
52 #define SOCKET_TIMEOUT2 20 * 1000
53
54 void
55 client::flush ()
56 {
57 if (destroyed ())
58 return;
59
60 #ifdef __linux__
61 // check time of last ack, and, if too old, kill connection
62 struct tcp_info tcpi;
63 socklen_t len = sizeof (tcpi);
64
65 if (!getsockopt (fd, IPPROTO_TCP, TCP_INFO, &tcpi, &len) && len == sizeof (tcpi))
66 {
67 unsigned int diff = tcpi.tcpi_last_ack_recv - tcpi.tcpi_last_data_sent;
68
69 rtt = tcpi.tcpi_rtt;
70 rttvar = tcpi.tcpi_rttvar;
71
72 if (tcpi.tcpi_unacked && SOCKET_TIMEOUT1 < diff && diff < 0x80000000UL // ack delayed for 20s
73 && SOCKET_TIMEOUT2 < tcpi.tcpi_last_data_sent) // no data sent for 10s
74 {
75 LOG (llevDebug, "Connection on fd %d closed due to ack timeout (%u/%u/%u)\n", fd,
76 (unsigned) tcpi.tcpi_last_ack_recv, (unsigned) tcpi.tcpi_last_data_sent, (unsigned) tcpi.tcpi_unacked);
77 destroy ();
78 }
79 }
80 #endif
81
82 /**
83 * Writes data to socket.
84 *
85 * When the socket is clear to write, and we have backlogged data, this
86 * is called to write it out.
87 */
88
89 if (!outputbuffer.len || socket_ev.poll () & PE_W)
90 return;
91
92 write_outputbuffer ();
93 }
94
95 void
96 client::write_outputbuffer ()
97 {
98 while (outputbuffer.len)
99 {
100 int res = write (fd, outputbuffer.data + outputbuffer.start,
101 min (outputbuffer.len, SOCKETBUFSIZE - outputbuffer.start));
102
103 if (res > 0)
104 {
105 outputbuffer.start += res;
106 /* wrap back to start of buffer */
107 if (outputbuffer.start == SOCKETBUFSIZE)
108 outputbuffer.start = 0;
109
110 outputbuffer.len -= res;
111 #ifdef CS_LOGSTATS
112 cst_tot.obytes += res;
113 cst_lst.obytes += res;
114 #endif
115 }
116 else if (res == 0)
117 {
118 LOG (llevError, "socket write failed, connection closed.\n");
119 destroy ();
120 return;
121 }
122 else if (errno == EINTR)
123 {
124 // just retry
125 }
126 else if (errno == EAGAIN)
127 {
128 // delay till ready
129 socket_ev.poll (socket_ev.poll () | PE_W);
130 socket_ev.start ();
131 return;
132 }
133 else
134 {
135 LOG (llevError, "socket write failed: %s\n", strerror (errno));
136 destroy ();
137 return;
138 }
139 }
140
141 socket_ev.poll (socket_ev.poll () & ~PE_W);
142 }
143
144 /******************************************************************************
145 *
146 * Start of read routines.
147 *
148 ******************************************************************************/
149
150 int
151 client::next_packet ()
152 {
153 if (inbuf_len >= 2)
154 {
155 int pkt_len = (inbuf [0] << 8) | inbuf [1];
156
157 if (inbuf_len >= 2 + pkt_len)
158 return 2 + pkt_len;
159
160 if (inbuf_len == sizeof (inbuf))
161 {
162 send_packet_printf ("drawinfo %d input buffer overflow - closing connection.", NDI_RED);
163 destroy ();
164 return -1;
165 }
166 }
167
168 return 0;
169 }
170
171 void
172 client::skip_packet (int len)
173 {
174 inbuf_len -= len;
175 memmove (inbuf, inbuf + len, inbuf_len);
176 }
177
178 /*****************************************************************************
179 * Start of command dispatch area.
180 * The commands here are protocol commands.
181 ****************************************************************************/
182
183 // SocketCommand, PlayingCommand, should not exist with those ugly casts
184 #define SC(cb) (void *)static_cast<void (*)(char *, int, client *)>(cb),
185 #define PC(cb) (void *)static_cast<void (*)(char *, int, player *)>(cb), PF_PLAYER |
186
187 /**
188 * Dispatch table for the server.
189 */
190 static struct packet_type packets[] = {
191 {"ncom", PC(NewPlayerCmd) PF_PLAYING | PF_COMMAND6 },
192 {"command", PC(PlayerCmd) PF_PLAYING | PF_COMMAND0 },
193
194 {"examine", PC(ExamineCmd) PF_PLAYING },
195 {"ex", PC(ExCmd) PF_PLAYING },
196 {"apply", PC(ApplyCmd) PF_PLAYING },
197 {"lookat", PC(LookAt) PF_PLAYING },
198 {"lock", PC(LockItem) PF_PLAYING },
199 {"mark", PC(MarkItem) PF_PLAYING },
200 {"move", PC(MoveCmd) PF_PLAYING },
201 {"ext", PC(ExtCmd) 0 }, // CF+
202 {"mapredraw", PC(MapRedrawCmd) 0 },
203 {"mapinfo", PC(MapInfoCmd) 0 }, // CF+
204
205 {"reply", SC(ReplyCmd) 0 },
206 {"exti", SC(ExtiCmd) 0 }, // CF+
207 {"addme", SC(AddMeCmd) 0 },
208 {"askface", SC(AskFaceCmd) 0 },
209 {"requestinfo", SC(RequestInfo) 0 },
210 {"setfacemode", SC(SetFaceMode) 0 },
211 {"setsound", SC(SetSound) 0 },
212 {"setup", SC(SetUp) 0 },
213 {"version", SC(VersionCmd) 0 },
214 {"toggleextendedinfos", SC(ToggleExtendedInfos) 0 }, /*Added: tchize */
215 {"toggleextendedtext", SC(ToggleExtendedText) 0 }, /*Added: tchize */
216 {"asksmooth", SC(AskSmooth) 0 }, /*Added: tchize (smoothing technologies) */
217 };
218
219 bool
220 client::may_execute (const packet_type *pkt) const
221 {
222 return (!(pkt->flags & PF_PLAYER) || pl)
223 && (!(pkt->flags & PF_PLAYING) || state == ST_PLAYING);
224 }
225
226 // HACK: some commands currently should be executed
227 // even when the player is frozen. this hack detects
228 // those commands. it should be folded into may_execute,
229 // but kept seperate to emphasise the hack aspect, i.e.
230 // do it better, then remove.
231 static bool
232 always_immediate (const client *ns, const packet_type *pkt, const char *data, int len)
233 {
234 if (!(pkt->flags & (PF_COMMAND0 | PF_COMMAND6)))
235 return false;
236
237 if (!ns->pl || !ns->pl->ob || !ns->pl->ob->map)
238 return false;
239
240 if (pkt->flags & PF_COMMAND6)
241 {
242 data += 6;
243 len -= 6;
244 }
245
246 if (len > 4 && !strncmp (data, "say " , 4))
247 return true;
248 if (len > 5 && !strncmp (data, "chat ", 5))
249 return true;
250
251 return false;
252 }
253
254 void
255 client::execute (const packet_type *pkt, char *data, int datalen)
256 {
257 if (may_execute (pkt) || always_immediate (this, pkt, data, datalen))
258 {
259 //TODO: only one format
260 if (pkt->flags & PF_PLAYER)
261 ((void (*)(char *, int, player *))pkt->cb)((char *)data, datalen, pl);
262 else
263 ((void (*)(char *, int, client *))pkt->cb)((char *)data, datalen, this);
264 }
265 else
266 send_packet_printf ("drawinfo %d ERROR: you cannot execute '%s' now.", NDI_RED, pkt->name);
267 }
268
269 bool
270 client::handle_packet ()
271 {
272 int pkt_len = next_packet ();
273
274 if (!pkt_len)
275 return false;
276 else if (pkt_len < 0)
277 {
278 LOG (llevError, "read error on player %s\n",
279 pl && pl->ob ? &pl->ob->name : "[anonymous]");
280 destroy ();
281 return false;
282 }
283
284 inbuf [pkt_len] = 0; /* Terminate buffer - useful for string data */
285
286 /* First, break out beginning word. There are at least
287 * a few commands that do not have any paremeters. If
288 * we get such a command, don't worry about trying
289 * to break it up.
290 */
291 int datalen;
292 char *data = strchr ((char *)inbuf + 2, ' ');
293
294 if (data)
295 {
296 *data++ = 0;
297 datalen = pkt_len - (data - (char *)inbuf);
298 }
299 else
300 {
301 data = (char *)inbuf + 2; // better read garbage than segfault
302 datalen = 0;
303 }
304
305 for (packet_type *pkt = packets; pkt < packets + (sizeof (packets) / sizeof (packets[0])); ++pkt)
306 if (!strcmp ((char *)inbuf + 2, pkt->name))
307 {
308 if (pkt->flags & PF_PLAYER && !always_immediate (this, pkt, data, datalen))
309 queue_command (pkt, data, datalen);
310 else
311 execute (pkt, data, datalen);
312
313 goto next_packet;
314 }
315
316 // If we get here, we didn't find a valid command.
317 send_packet_printf ("drawinfo %d ERROR: command '%s' not supported.", NDI_RED, (char *)inbuf + 2);
318 next_packet:
319 skip_packet (pkt_len);
320
321 // input buffer has space again
322 socket_ev.poll (socket_ev.poll () | PE_R);
323
324 return true;
325 }
326
327 // callback called when socket is either readable or writable
328 void
329 client::socket_cb (iow &w, int got)
330 {
331 //TODO remove when we have better socket cleanup logic
332 if (destroyed ())
333 {
334 socket_ev.poll (0);
335 return;
336 }
337
338 if (got & PE_W)
339 {
340 write_outputbuffer ();
341
342 if (!outputbuffer.len)
343 socket_ev.poll (socket_ev.poll () & ~PE_W);
344 }
345
346 if (got & PE_R)
347 {
348 //TODO: rate-limit tcp connection in better ways, important
349
350 int amount = sizeof (inbuf) - inbuf_len;
351
352 if (!amount)
353 {
354 // input buffer full
355 socket_ev.poll (socket_ev.poll () & ~PE_R);
356 return;
357 }
358
359 amount = read (fd, inbuf + inbuf_len, amount);
360
361 if (!amount)
362 {
363 destroy ();
364 return;
365 }
366 else if (amount < 0)
367 {
368 if (errno != EAGAIN && errno != EINTR)
369 {
370 LOG (llevError, "read error: %s\n", strerror (errno));
371 destroy ();
372 return;
373 }
374
375 // should not be here, normally
376 }
377 else
378 {
379 inbuf_len += amount;
380
381 cst_tot.ibytes += amount;
382 cst_lst.ibytes += amount;
383
384 cmd_ev.start ();
385 }
386 }
387 }
388
389 // called whenever we have additional commands to process
390 void
391 client::cmd_cb (iw &w)
392 {
393 if (handle_packet ())
394 w.start ();
395 else
396 flush ();
397 }
398
399 /*******************************************************************************
400 *
401 * Start of write related routines.
402 *
403 ******************************************************************************/
404
405 /**
406 * Adds data to a socket buffer for whatever reason.
407 *
408 * ns is the socket we are adding the data to, buf is the start of the
409 * data, and len is the number of bytes to add.
410 */
411 void
412 client::send (void *buf_, int len)
413 {
414 char *buf = (char *)buf_;
415
416 if (destroyed () || !buf)
417 return;
418
419 if (len + outputbuffer.len > SOCKETBUFSIZE)
420 {
421 LOG (llevDebug, "socket on fd %d has overrun internal buffer - marking as dead\n", fd);
422 // shutdown the socket, this is safer than destroying it immediately
423 // as lots of code in the callchain might still access the map etc.
424 shutdown (fd, SHUT_RDWR);
425 return;
426 }
427
428 int avail, end;
429
430 /* data + end is where we start putting the new data. The last byte
431 * currently in use is actually data + end -1
432 */
433 end = outputbuffer.start + outputbuffer.len;
434 /* The buffer is already in a wrapped state, so adjust end */
435 if (end >= SOCKETBUFSIZE)
436 end -= SOCKETBUFSIZE;
437
438 avail = SOCKETBUFSIZE - end;
439
440 /* We can all fit it behind the current data without wrapping */
441 if (avail >= len)
442 memcpy (outputbuffer.data + end, buf, len);
443 else
444 {
445 memcpy (outputbuffer.data + end, buf, avail);
446 memcpy (outputbuffer.data, buf + avail, len - avail);
447 }
448
449 outputbuffer.len += len;
450 }
451
452 /**
453 * Takes a string of data, and writes it out to the socket. A very handy
454 * shortcut function.
455 */
456 void
457 client::send_packet (packet &sl)
458 {
459 if (destroyed ())
460 return;
461
462 if (sl.length () >= MAXSOCKBUF)
463 {
464 LOG (llevError, "Trying to send a buffer beyond properly size, len =%d\n", sl.length ());
465 /* Almost certainly we've overflowed a buffer, so quit now to make
466 * it easier to debug.
467 */
468 abort ();
469 }
470
471 if (!sl.length ())
472 return;
473
474 assert (sl.hdrlen == 2);
475
476 sl.buf_ [0] = sl.length () >> 8;
477 sl.buf_ [1] = sl.length () ;
478
479 send (sl.buf_, sl.length () + sl.hdrlen);
480 }
481
482 void
483 client::send_packet (const char *buf, int len)
484 {
485 packet sl;
486
487 sl << data (buf, len);
488 send_packet (sl);
489 }
490
491 void
492 client::send_packet (const char *buf)
493 {
494 send_packet (buf, strlen (buf));
495 }
496
497 void
498 client::send_packet_printf (const char *format, ...)
499 {
500 packet sl;
501
502 va_list ap;
503 va_start (ap, format);
504 sl.vprintf (format, ap);
505 va_end (ap);
506
507 send_packet (sl);
508 }
509
510 void
511 client::send_drawinfo (const char *msg, int flags)
512 {
513 send_packet_printf ("drawinfo %d %s", flags, msg);
514 }
515
516 void
517 client::send_msg (int color, const char *type, const char *msg)
518 {
519 if (can_msg)
520 send_packet_printf ("msg %d %s %s", color, type, msg);
521 else if (color < 0)
522 return; // client cannot handle this
523 else if (strchr (msg, '<') || strchr (msg, '&'))
524 {
525 //TODO: should escape/modify to old syntax
526 send_packet_printf ("drawinfo %d %s", color, msg);
527 }
528 else
529 send_packet_printf ("drawinfo %d %s", color, msg);
530 }
531
532 /***********************************************************************
533 *
534 * packet functions/utilities
535 *
536 **********************************************************************/
537
538 packet::packet (const char *name)
539 {
540 reset ();
541
542 int len = strlen (name);
543 memcpy (cur, name, len); cur += len;
544 *cur++ = ' ';
545 }
546
547 packet &packet::operator <<(const ber32 v)
548 {
549 enum { maxlen = 32 / 7 + 1};
550 uint8 buf[maxlen];
551 uint8 *p = buf + maxlen;
552 uint32 val = v.val;
553
554 *--p = val & 0x7F;
555
556 while (val > 0x7F)
557 {
558 val >>= 7;
559 *--p = (val & 0x7F) | 0x80;
560 }
561
562 return *this << data (p, buf + maxlen - p);
563 }
564
565 packet &packet::operator <<(const data &v)
566 {
567 if (room () < v.len)
568 reset ();
569 else
570 {
571 if (v.len)
572 {
573 memcpy (cur, v.ptr, v.len);
574 cur += v.len;
575 }
576 }
577
578 return *this;
579 }
580
581 packet &packet::operator <<(const data8 &v)
582 {
583 unsigned int len = min (v.len, 0x00FF);
584 return *this << uint8 (len) << data (v.ptr, len);
585 }
586
587 packet &packet::operator <<(const data16 &v)
588 {
589 unsigned int len = min (v.len, 0xFFFF);
590 return *this << uint16 (len) << data (v.ptr, len);
591 }
592
593 packet &packet::operator <<(const char *v)
594 {
595 return *this << data (v, strlen (v ? v : 0));
596 }
597
598 void
599 packet::vprintf (const char *format, va_list ap)
600 {
601 int size = room ();
602
603 int len = vsnprintf ((char *)cur, size, format, ap);
604
605 if (len >= size)
606 return reset ();
607
608 cur += len;
609 }
610
611 /******************************************************************************
612 *
613 * statistics logging functions.
614 *
615 ******************************************************************************/
616
617 #ifdef CS_LOGSTATS
618
619 /* cst_tot is for the life of the server, cst_last is for the last series of
620 * stats
621 */
622 CS_Stats cst_tot, cst_lst;
623
624 /**
625 * Writes out the gathered stats. We clear cst_lst.
626 */
627 void
628 write_cs_stats (void)
629 {
630 time_t now = time (NULL);
631
632 /* If no connections recently, don't both to log anything */
633 if (cst_lst.ibytes == 0 && cst_lst.obytes == 0)
634 return;
635
636 /* CSSTAT is put in so scripts can easily find the line */
637 LOG (llevInfo, "CSSTAT: %.16s tot %d %d %d %d inc %d %d %d %d\n",
638 ctime (&now), cst_tot.ibytes, cst_tot.obytes, cst_tot.max_conn,
639 now - cst_tot.time_start, cst_lst.ibytes, cst_lst.obytes, cst_lst.max_conn, now - cst_lst.time_start);
640 cst_lst.ibytes = 0;
641 cst_lst.obytes = 0;
642 cst_lst.time_start = now;
643 }
644 #endif
645