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/cvs/deliantra/server/socket/lowlevel.C
Revision: 1.45
Committed: Sun Jun 10 02:51:46 2007 UTC (16 years, 11 months ago) by root
Content type: text/plain
Branch: MAIN
Changes since 1.44: +2 -14 lines
Log Message:
use configure to check for tcp_info

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 using namespace std;
25
26 #include <global.h>
27 #include <sproto.h>
28 #include <cstdarg>
29
30 #if HAVE_TCP_INFO
31 # include <sys/types.h>
32 # include <sys/socket.h>
33 # include <netinet/in.h>
34 # include <netinet/tcp.h>
35 #endif
36
37 // disconnect a socket after this many seconds without an ack
38 #define SOCKET_TIMEOUT 8.
39
40 // force a packet when idle for more than this many seconds,
41 // forcing an ack regularly.
42 #define IDLE_PING 2.
43
44 void
45 client::flush ()
46 {
47 if (destroyed ())
48 return;
49
50 #if HAVE_TCP_INFO
51 // check about once per second, spread evenly over all clients
52 if (!((pticks + fd) & 7))
53 {
54 // check time of last ack, and, if too old, kill connection
55 struct tcp_info tcpi;
56 socklen_t len = sizeof (tcpi);
57
58 if (!getsockopt (fd, IPPROTO_TCP, TCP_INFO, &tcpi, &len) && len == sizeof (tcpi))
59 {
60 rtt = tcpi.tcpi_rtt;
61 rttvar = tcpi.tcpi_rttvar;
62
63 if (tcpi.tcpi_last_ack_recv > int (SOCKET_TIMEOUT * 1000))
64 {
65 send_msg (NDI_RED, "connection-timeout", "safety disconnect due to tcp/ip timeout (no packets received)");
66 write_outputbuffer ();
67
68 LOG (llevDebug, "connection on fd %d closed due to ack timeout (%u/%u/%u)\n", fd,
69 (unsigned)tcpi.tcpi_last_ack_recv, (unsigned)tcpi.tcpi_last_data_sent, (unsigned)tcpi.tcpi_unacked);
70 destroy ();
71 }
72 }
73 }
74 #endif
75
76 /**
77 * Writes data to socket.
78 *
79 * When the socket is clear to write, and we have backlogged data, this
80 * is called to write it out.
81 */
82
83 // write a nop to the socket at least every IDLE_NOP seconds.
84 if (!outputbuffer.len)
85 {
86 if (last_send + IDLE_PING <= NOW)
87 {
88 // this is a bit ugly, but map1/map1a seem to be the only
89 // nop'able commands and they are quite small.
90 packet sl (mapmode == Map1Cmd ? "map1" : "map1a");
91 send_packet (sl);
92 }
93 else
94 return;
95 }
96
97 if (socket_ev.poll () & PE_W)
98 return;
99
100 last_send = NOW;
101 write_outputbuffer ();
102 }
103
104 void
105 client::write_outputbuffer ()
106 {
107 while (outputbuffer.len)
108 {
109 int res = write (fd, outputbuffer.data + outputbuffer.start,
110 min (outputbuffer.len, SOCKETBUFSIZE - outputbuffer.start));
111
112 if (res > 0)
113 {
114 outputbuffer.start += res;
115 /* wrap back to start of buffer */
116 if (outputbuffer.start == SOCKETBUFSIZE)
117 outputbuffer.start = 0;
118
119 outputbuffer.len -= res;
120 }
121 else if (res == 0)
122 {
123 LOG (llevError, "socket write failed, connection closed.\n");
124 destroy ();
125 return;
126 }
127 else if (errno == EINTR)
128 {
129 // just retry
130 }
131 else if (errno == EAGAIN)
132 {
133 // delay till ready
134 socket_ev.poll (socket_ev.poll () | PE_W);
135 socket_ev.start ();
136 return;
137 }
138 else
139 {
140 LOG (llevError, "socket write failed: %s\n", strerror (errno));
141 destroy ();
142 return;
143 }
144 }
145
146 socket_ev.poll (socket_ev.poll () & ~PE_W);
147 }
148
149 /******************************************************************************
150 *
151 * Start of read routines.
152 *
153 ******************************************************************************/
154
155 int
156 client::next_packet ()
157 {
158 if (inbuf_len >= 2)
159 {
160 int pkt_len = (inbuf [0] << 8) | inbuf [1];
161
162 if (inbuf_len >= 2 + pkt_len)
163 return 2 + pkt_len;
164
165 if (inbuf_len == sizeof (inbuf))
166 {
167 send_packet_printf ("drawinfo %d input buffer overflow - closing connection.", NDI_RED);
168 destroy ();
169 return -1;
170 }
171 }
172
173 return 0;
174 }
175
176 void
177 client::skip_packet (int len)
178 {
179 inbuf_len -= len;
180 memmove (inbuf, inbuf + len, inbuf_len);
181 }
182
183 /*****************************************************************************
184 * Start of command dispatch area.
185 * The commands here are protocol commands.
186 ****************************************************************************/
187
188 // SocketCommand, PlayingCommand, should not exist with those ugly casts
189 #define SC(cb) (void *)static_cast<void (*)(char *, int, client *)>(cb),
190 #define PC(cb) (void *)static_cast<void (*)(char *, int, player *)>(cb), PF_PLAYER |
191
192 /**
193 * Dispatch table for the server.
194 */
195 static struct packet_type packets[] = {
196 {"ncom", PC(NewPlayerCmd) PF_PLAYING | PF_COMMAND6 },
197 {"command", PC(PlayerCmd) PF_PLAYING | PF_COMMAND0 },
198
199 {"examine", PC(ExamineCmd) PF_PLAYING },
200 {"ex", PC(ExCmd) PF_PLAYING },
201 {"apply", PC(ApplyCmd) PF_PLAYING },
202 {"lookat", PC(LookAt) PF_PLAYING },
203 {"lock", PC(LockItem) PF_PLAYING },
204 {"mark", PC(MarkItem) PF_PLAYING },
205 {"move", PC(MoveCmd) PF_PLAYING },
206 {"ext", PC(ExtCmd) 0 }, // CF+
207 {"mapredraw", PC(MapRedrawCmd) 0 },
208 {"mapinfo", PC(MapInfoCmd) 0 }, // CF+
209
210 {"reply", SC(ReplyCmd) 0 },
211 {"exti", SC(ExtiCmd) 0 }, // CF+
212 {"addme", SC(AddMeCmd) 0 },
213 {"askface", SC(AskFaceCmd) 0 },
214 {"requestinfo", SC(RequestInfo) 0 },
215 {"setfacemode", SC(SetFaceMode) 0 },
216 {"setsound", SC(SetSound) 0 },
217 {"setup", SC(SetUp) 0 },
218 {"version", SC(VersionCmd) 0 },
219 {"toggleextendedinfos", SC(ToggleExtendedInfos) 0 }, /*Added: tchize */
220 {"toggleextendedtext", SC(ToggleExtendedText) 0 }, /*Added: tchize */
221 {"asksmooth", SC(AskSmooth) 0 }, /*Added: tchize (smoothing technologies) */
222 };
223
224 bool
225 client::may_execute (const packet_type *pkt) const
226 {
227 return (!(pkt->flags & PF_PLAYER) || pl)
228 && (!(pkt->flags & PF_PLAYING) || state == ST_PLAYING);
229 }
230
231 // HACK: some commands currently should be executed
232 // even when the player is frozen. this hack detects
233 // those commands. it should be folded into may_execute,
234 // but kept seperate to emphasise the hack aspect, i.e.
235 // do it better, then remove.
236 static bool
237 always_immediate (const client *ns, const packet_type *pkt, const char *data, int len)
238 {
239 if (!(pkt->flags & (PF_COMMAND0 | PF_COMMAND6)))
240 return false;
241
242 if (!ns->pl || !ns->pl->ob || !ns->pl->ob->map)
243 return false;
244
245 if (pkt->flags & PF_COMMAND6)
246 {
247 data += 6;
248 len -= 6;
249 }
250
251 if (len > 4 && !strncmp (data, "say " , 4))
252 return true;
253 if (len > 5 && !strncmp (data, "chat ", 5))
254 return true;
255
256 return false;
257 }
258
259 void
260 client::execute (const packet_type *pkt, char *data, int datalen)
261 {
262 if (may_execute (pkt) || always_immediate (this, pkt, data, datalen))
263 {
264 //TODO: only one format
265 if (pkt->flags & PF_PLAYER)
266 ((void (*)(char *, int, player *))pkt->cb)((char *)data, datalen, pl);
267 else
268 ((void (*)(char *, int, client *))pkt->cb)((char *)data, datalen, this);
269 }
270 else
271 send_packet_printf ("drawinfo %d ERROR: you cannot execute '%s' now.", NDI_RED, pkt->name);
272 }
273
274 bool
275 client::handle_packet ()
276 {
277 int pkt_len = next_packet ();
278
279 if (!pkt_len)
280 return false;
281 else if (pkt_len < 0)
282 {
283 LOG (llevError, "read error on player %s\n",
284 pl && pl->ob ? &pl->ob->name : "[anonymous]");
285 destroy ();
286 return false;
287 }
288
289 inbuf [pkt_len] = 0; /* Terminate buffer - useful for string data */
290
291 /* First, break out beginning word. There are at least
292 * a few commands that do not have any paremeters. If
293 * we get such a command, don't worry about trying
294 * to break it up.
295 */
296 int datalen;
297 char *data = strchr ((char *)inbuf + 2, ' ');
298
299 if (data)
300 {
301 *data++ = 0;
302 datalen = pkt_len - (data - (char *)inbuf);
303 }
304 else
305 {
306 data = (char *)inbuf + 2; // better read garbage than segfault
307 datalen = 0;
308 }
309
310 for (packet_type *pkt = packets; pkt < packets + (sizeof (packets) / sizeof (packets[0])); ++pkt)
311 if (!strcmp ((char *)inbuf + 2, pkt->name))
312 {
313 if (pkt->flags & PF_PLAYER && !always_immediate (this, pkt, data, datalen))
314 queue_command (pkt, data, datalen);
315 else
316 execute (pkt, data, datalen);
317
318 goto next_packet;
319 }
320
321 // If we get here, we didn't find a valid command.
322 send_packet_printf ("drawinfo %d ERROR: command '%s' not supported.", NDI_RED, (char *)inbuf + 2);
323 next_packet:
324 skip_packet (pkt_len);
325
326 // input buffer has space again
327 socket_ev.poll (socket_ev.poll () | PE_R);
328
329 return true;
330 }
331
332 // callback called when socket is either readable or writable
333 void
334 client::socket_cb (iow &w, int got)
335 {
336 //TODO remove when we have better socket cleanup logic
337 if (destroyed ())
338 {
339 socket_ev.poll (0);
340 return;
341 }
342
343 if (got & PE_W)
344 {
345 write_outputbuffer ();
346
347 if (!outputbuffer.len)
348 socket_ev.poll (socket_ev.poll () & ~PE_W);
349 }
350
351 if (got & PE_R)
352 {
353 //TODO: rate-limit tcp connection in better ways, important
354
355 int amount = sizeof (inbuf) - inbuf_len;
356
357 if (!amount)
358 {
359 // input buffer full
360 socket_ev.poll (socket_ev.poll () & ~PE_R);
361 return;
362 }
363
364 amount = read (fd, inbuf + inbuf_len, amount);
365
366 if (!amount)
367 {
368 destroy ();
369 return;
370 }
371 else if (amount < 0)
372 {
373 if (errno != EAGAIN && errno != EINTR)
374 {
375 LOG (llevError, "read error: %s\n", strerror (errno));
376 destroy ();
377 return;
378 }
379
380 // should not be here, normally
381 }
382 else
383 {
384 inbuf_len += amount;
385
386 cmd_ev.start ();
387 }
388 }
389 }
390
391 // called whenever we have additional commands to process
392 void
393 client::cmd_cb (iw &w)
394 {
395 if (handle_packet ())
396 w.start ();
397 else
398 flush ();
399 }
400
401 /*******************************************************************************
402 *
403 * Start of write related routines.
404 *
405 ******************************************************************************/
406
407 /**
408 * Adds data to a socket buffer for whatever reason.
409 *
410 * ns is the socket we are adding the data to, buf is the start of the
411 * data, and len is the number of bytes to add.
412 */
413 void
414 client::send (void *buf_, int len)
415 {
416 char *buf = (char *)buf_;
417
418 if (destroyed () || !buf)
419 return;
420
421 if (len + outputbuffer.len > SOCKETBUFSIZE)
422 {
423 LOG (llevDebug, "socket on fd %d has overrun internal buffer - marking as dead\n", fd);
424 // shutdown the socket, this is safer than destroying it immediately
425 // as lots of code in the callchain might still access the map etc.
426 shutdown (fd, SHUT_RDWR);
427 return;
428 }
429
430 int avail, end;
431
432 /* data + end is where we start putting the new data. The last byte
433 * currently in use is actually data + end -1
434 */
435 end = outputbuffer.start + outputbuffer.len;
436 /* The buffer is already in a wrapped state, so adjust end */
437 if (end >= SOCKETBUFSIZE)
438 end -= SOCKETBUFSIZE;
439
440 avail = SOCKETBUFSIZE - end;
441
442 /* We can all fit it behind the current data without wrapping */
443 if (avail >= len)
444 memcpy (outputbuffer.data + end, buf, len);
445 else
446 {
447 memcpy (outputbuffer.data + end, buf, avail);
448 memcpy (outputbuffer.data, buf + avail, len - avail);
449 }
450
451 outputbuffer.len += len;
452 }
453
454 /**
455 * Takes a string of data, and writes it out to the socket. A very handy
456 * shortcut function.
457 */
458 void
459 client::send_packet (packet &sl)
460 {
461 if (destroyed ())
462 return;
463
464 if (sl.length () >= MAXSOCKBUF)
465 {
466 LOG (llevError, "Trying to send a buffer beyond properly size, len =%d\n", sl.length ());
467 /* Almost certainly we've overflowed a buffer, so quit now to make
468 * it easier to debug.
469 */
470 abort ();
471 }
472
473 if (!sl.length ())
474 return;
475
476 assert (sl.hdrlen == 2);
477
478 sl.buf_ [0] = sl.length () >> 8;
479 sl.buf_ [1] = sl.length () ;
480
481 send (sl.buf_, sl.length () + sl.hdrlen);
482 }
483
484 void
485 client::send_packet (const char *buf, int len)
486 {
487 packet sl;
488
489 sl << data (buf, len);
490 send_packet (sl);
491 }
492
493 void
494 client::send_packet (const char *buf)
495 {
496 send_packet (buf, strlen (buf));
497 }
498
499 void
500 client::send_packet_printf (const char *format, ...)
501 {
502 packet sl;
503
504 va_list ap;
505 va_start (ap, format);
506 sl.vprintf (format, ap);
507 va_end (ap);
508
509 send_packet (sl);
510 }
511
512 void
513 client::send_drawinfo (const char *msg, int flags)
514 {
515 send_packet_printf ("drawinfo %d %s", flags, msg);
516 }
517
518 void
519 client::send_msg (int color, const char *type, const char *msg)
520 {
521 if (can_msg)
522 send_packet_printf ("msg %d %s %s", color, type, msg);
523 else if (color < 0)
524 return; // client cannot handle this
525 else if (strchr (msg, '<') || strchr (msg, '&'))
526 {
527 //TODO: should escape/modify to old syntax
528 send_packet_printf ("drawinfo %d %s", color, msg);
529 }
530 else
531 send_packet_printf ("drawinfo %d %s", color, msg);
532 }
533
534 /***********************************************************************
535 *
536 * packet functions/utilities
537 *
538 **********************************************************************/
539
540 packet::packet (const char *name)
541 {
542 reset ();
543
544 int len = strlen (name);
545 memcpy (cur, name, len); cur += len;
546 *cur++ = ' ';
547 }
548
549 packet &packet::operator <<(const ber32 v)
550 {
551 enum { maxlen = 32 / 7 + 1};
552 uint8 buf[maxlen];
553 uint8 *p = buf + maxlen;
554 uint32 val = v.val;
555
556 *--p = val & 0x7F;
557
558 while (val > 0x7F)
559 {
560 val >>= 7;
561 *--p = (val & 0x7F) | 0x80;
562 }
563
564 return *this << data (p, buf + maxlen - p);
565 }
566
567 packet &packet::operator <<(const data &v)
568 {
569 if (room () < v.len)
570 reset ();
571 else
572 {
573 if (v.len)
574 {
575 memcpy (cur, v.ptr, v.len);
576 cur += v.len;
577 }
578 }
579
580 return *this;
581 }
582
583 packet &packet::operator <<(const data8 &v)
584 {
585 unsigned int len = min (v.len, 0x00FF);
586 return *this << uint8 (len) << data (v.ptr, len);
587 }
588
589 packet &packet::operator <<(const data16 &v)
590 {
591 unsigned int len = min (v.len, 0xFFFF);
592 return *this << uint16 (len) << data (v.ptr, len);
593 }
594
595 packet &packet::operator <<(const char *v)
596 {
597 return *this << data (v, strlen (v ? v : 0));
598 }
599
600 void
601 packet::vprintf (const char *format, va_list ap)
602 {
603 int size = room ();
604
605 int len = vsnprintf ((char *)cur, size, format, ap);
606
607 if (len >= size)
608 return reset ();
609
610 cur += len;
611 }
612