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/cvs/deliantra/server/socket/lowlevel.c
Revision: 1.6
Committed: Sun Aug 13 17:16:06 2006 UTC (17 years, 9 months ago) by elmex
Content type: text/plain
Branch: MAIN
CVS Tags: HEAD
Changes since 1.5: +0 -0 lines
State: FILE REMOVED
Log Message:
Made server compile with C++.
Removed cfanim plugin and crossedit.
C++ here we come.

File Contents

# Content
1
2 /*
3 * static char *rcsid_sockets_c =
4 * "$Id$";
5 */
6
7 /*
8 CrossFire, A Multiplayer game for X-windows
9
10 Copyright (C) 1992 Frank Tore Johansen
11
12 This program is free software; you can redistribute it and/or modify
13 it under the terms of the GNU General Public License as published by
14 the Free Software Foundation; either version 2 of the License, or
15 (at your option) any later version.
16
17 This program is distributed in the hope that it will be useful,
18 but WITHOUT ANY WARRANTY; without even the implied warranty of
19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 GNU General Public License for more details.
21
22 You should have received a copy of the GNU General Public License
23 along with this program; if not, write to the Free Software
24 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25
26 The author can be reached via e-mail to mark@pyramid.com
27 */
28
29 /**
30 * \file
31 * Low-level socket-related functions.
32 *
33 * \date 2003-12-02
34 *
35 * Contains some base functions that both the client and server
36 * can use. As such, depending what we are being compiled for will
37 * determine what we can include. the client is designed have
38 * CFCLIENT defined as part of its compile flags.
39 */
40
41 #include <global.h>
42 #include <newclient.h>
43 #include <sproto.h>
44
45 #ifdef __linux__
46 # include <sys/types.h>
47 # include <sys/socket.h>
48 # include <netinet/in.h>
49 # define TCP_HZ 1000 // sorry...
50 # include <netinet/tcp.h>
51 #endif
52
53 // use a really low timeout, as it doesn't cost any bandwidth, and you can
54 // easily die in 20 seconds...
55 #define SOCKET_TIMEOUT1 10
56 #define SOCKET_TIMEOUT2 20
57
58 void Socket_Flush (NewSocket *ns)
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 (ns->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 if (tcpi.tcpi_unacked
70 && SOCKET_TIMEOUT1 * TCP_HZ < diff && diff < 0x80000000UL // ack delayed for 20s
71 && SOCKET_TIMEOUT2 * TCP_HZ < tcpi.tcpi_last_data_sent) // no data sent for 10s
72 {
73 LOG (llevDebug, "Connection on fd %d closed due to ack timeout (%u/%u/%u)\n", ns->fd,
74 (unsigned)tcpi.tcpi_last_ack_recv, (unsigned)tcpi.tcpi_last_data_sent, (unsigned)tcpi.tcpi_unacked);
75 ns->status = Ns_Dead;
76 }
77 }
78
79 int val;
80 val = 0; setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val));
81 val = 1; setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val));
82 #endif
83 }
84
85 /***********************************************************************
86 *
87 * SockList functions/utilities
88 *
89 **********************************************************************/
90
91 void SockList_Init(SockList *sl)
92 {
93 sl->len=0;
94 sl->buf=NULL;
95 }
96
97 void SockList_AddChar(SockList *sl, char c)
98 {
99 sl->buf[sl->len]=c;
100 sl->len++;
101 }
102
103 void SockList_AddShort(SockList *sl, uint16 data)
104 {
105 sl->buf[sl->len++]= (data>>8)&0xff;
106 sl->buf[sl->len++] = data & 0xff;
107 }
108
109
110 void SockList_AddInt(SockList *sl, uint32 data)
111 {
112 sl->buf[sl->len++]= (data>>24)&0xff;
113 sl->buf[sl->len++]= (data>>16)&0xff;
114 sl->buf[sl->len++]= (data>>8)&0xff;
115 sl->buf[sl->len++] = data & 0xff;
116 }
117
118 void SockList_AddInt64(SockList *sl, uint64 data)
119 {
120 sl->buf[sl->len++]= ( char )( (data>>56)&0xff );
121 sl->buf[sl->len++]= ( char )( (data>>48)&0xff );
122 sl->buf[sl->len++]= ( char )( (data>>40)&0xff );
123 sl->buf[sl->len++]= ( char )( (data>>32)&0xff );
124
125 sl->buf[sl->len++]= ( char )( (data>>24)&0xff );
126 sl->buf[sl->len++]= ( char )( (data>>16)&0xff );
127 sl->buf[sl->len++]= ( char )( (data>>8)&0xff );
128 sl->buf[sl->len++] =( char )( data & 0xff );
129 }
130
131 /* Basically does the reverse of SockList_AddInt, but on
132 * strings instead. Same for the GetShort, but for 16 bits.
133 */
134 int GetInt_String(unsigned char *data)
135 {
136 return ((data[0]<<24) + (data[1]<<16) + (data[2]<<8) + data[3]);
137 }
138
139 short GetShort_String(unsigned char *data) {
140 return ((data[0]<<8)+data[1]);
141 }
142
143 /******************************************************************************
144 *
145 * Start of read routines.
146 *
147 ******************************************************************************/
148
149 /**
150 * This reads from fd and puts the data in sl. We return true if we think
151 * we have a full packet, 0 if we have a partial packet. The only processing
152 * we do is remove the intial size value. len (As passed) is the size of the
153 * buffer allocated in the socklist. We make the assumption the buffer is
154 * at least 2 bytes long.
155 */
156
157 int SockList_ReadPacket(int fd, SockList *sl, int len)
158 {
159 int stat,toread;
160 extern int errno;
161
162 /* Sanity check - shouldn't happen */
163 if (sl->len < 0) {
164 abort();
165 }
166 /* We already have a partial packet */
167 if (sl->len<2) {
168 #ifdef WIN32 /* ***WIN32 SockList_ReadPacket: change read() to recv() */
169
170 stat=recv(fd, sl->buf + sl->len, 2-sl->len,0);
171
172 #else
173 do {
174 stat=read(fd, sl->buf + sl->len, 2-sl->len);
175 } while ((stat==-1) && (errno==EINTR));
176 #endif
177 if (stat<0) {
178 /* In non blocking mode, EAGAIN is set when there is no
179 * data available.
180 */
181 #ifdef WIN32 /* ***WIN32 SockList_ReadPacket: error handling for win32 */
182 if ((stat==-1) && WSAGetLastError() !=WSAEWOULDBLOCK) {
183 if(WSAGetLastError() == WSAECONNRESET)
184 LOG(llevDebug,"Connection closed by client\n");
185 else
186 {
187 LOG(llevDebug,"ReadPacket got error %d, returning 0\n",WSAGetLastError());
188 }
189 return -1; /* kick this user! */
190 }
191 #else
192 if (errno != EAGAIN && errno !=EWOULDBLOCK) {
193 LOG(llevDebug, "ReadPacket got error %s, returning 0\n", strerror_local(errno));
194 }
195 #endif
196 return 0; /*Error */
197 }
198 if (stat==0) return -1;
199 sl->len += stat;
200 #ifdef CS_LOGSTATS
201 cst_tot.ibytes += stat;
202 cst_lst.ibytes += stat;
203 #endif
204 if (stat<2) return 0; /* Still don't have a full packet */
205 }
206 /* Figure out how much more data we need to read. Add 2 from the
207 * end of this - size header information is not included.
208 */
209 toread = 2+(sl->buf[0] << 8) + sl->buf[1] - sl->len;
210 if ((toread + sl->len) >= len) {
211 LOG(llevError,"SockList_ReadPacket: Want to read more bytes than will fit in buffer (%d>=%d).\n",
212 toread + sl->len, len);
213 /* Quick hack in case for 'oldsocketmode' input. If we are
214 * closing the socket anyways, then reading this extra 100 bytes
215 * shouldn't hurt.
216 */
217 #ifdef WIN32 /* ***win32 SockList_ReadPacket: change read() to recv() */
218 recv(fd, sl->buf+2, 100, 0);
219 #else
220 read(fd, sl->buf+2, 100);
221 #endif /* end win32 */
222
223 /* return error so the socket is closed */
224 return -1;
225 }
226 do {
227 #ifdef WIN32 /* ***win32 SockList_ReadPacket: change read() to recv() */
228 stat = recv(fd, sl->buf+ sl->len, toread, 0);
229 #else
230 do {
231 stat = read(fd, sl->buf+ sl->len, toread);
232 } while ((stat<0) && (errno==EINTR));
233 #endif
234 if (stat<0) {
235
236 #ifdef WIN32 /* ***win32 SockList_ReadPacket: change error handling for win32 */
237 if ((stat==-1) && WSAGetLastError() !=WSAEWOULDBLOCK) {
238 if(WSAGetLastError() == WSAECONNRESET)
239 LOG(llevDebug,"Connection closed by client\n");
240 else
241 {
242 LOG(llevDebug,"ReadPacket got error %d, returning 0\n",WSAGetLastError());
243 }
244 return -1; /* kick this user! */
245 }
246 #else
247 if (errno != EAGAIN && errno !=EWOULDBLOCK) {
248 LOG(llevDebug, "ReadPacket got error %s, returning 0\n", strerror_local(errno));
249 }
250 #endif
251 return 0; /*Error */
252 }
253 if (stat==0) return -1;
254 sl->len += stat;
255 #ifdef CS_LOGSTATS
256 cst_tot.ibytes += stat;
257 cst_lst.ibytes += stat;
258 #endif
259 toread -= stat;
260 if (toread==0) return 1;
261 if (toread < 0) {
262 LOG(llevError,"SockList_ReadPacket: Read more bytes than desired.\n");
263 return 1;
264 }
265 } while (toread>0);
266 return 0;
267 }
268
269 /*******************************************************************************
270 *
271 * Start of write related routines.
272 *
273 ******************************************************************************/
274
275 /**
276 * Adds data to a socket buffer for whatever reason.
277 *
278 * ns is the socket we are adding the data to, buf is the start of the
279 * data, and len is the number of bytes to add.
280 */
281
282 static void add_to_buffer(NewSocket *ns, unsigned char *buf, int len)
283 {
284 int avail, end;
285
286 if ((len+ns->outputbuffer.len)>SOCKETBUFSIZE) {
287 LOG(llevDebug,"Socket on fd %d has overrun internal buffer - marking as dead\n",
288 ns->fd);
289 ns->status = Ns_Dead;
290 return;
291 }
292
293 /* data + end is where we start putting the new data. The last byte
294 * currently in use is actually data + end -1
295 */
296
297 end=ns->outputbuffer.start + ns->outputbuffer.len;
298 /* The buffer is already in a wrapped state, so adjust end */
299 if (end>=SOCKETBUFSIZE) end-=SOCKETBUFSIZE;
300 avail=SOCKETBUFSIZE - end;
301
302 /* We can all fit it behind the current data without wrapping */
303 if (avail >=len ) {
304 memcpy(ns->outputbuffer.data + end, buf, len);
305 }
306 else {
307 memcpy(ns->outputbuffer.data + end, buf, avail);
308 memcpy(ns->outputbuffer.data, buf+avail, len-avail);
309 }
310 ns->outputbuffer.len += len;
311 #if 0
312 LOG(llevDebug,"Added %d to output buffer, total length now %d, start=%d\n", len,
313 ns->outputbuffer.len, ns->outputbuffer.start);
314 #endif
315 }
316
317 /**
318 * Writes data to socket.
319 *
320 * When the socket is clear to write, and we have backlogged data, this
321 * is called to write it out.
322 */
323 void write_socket_buffer(NewSocket *ns)
324 {
325 int amt, max;
326
327 if (ns->outputbuffer.len==0) {
328 LOG(llevDebug,"write_socket_buffer called when there is no data, fd=%d\n",
329 ns->fd);
330 return;
331 }
332
333 do {
334 max = SOCKETBUFSIZE - ns->outputbuffer.start;
335 if (ns->outputbuffer.len<max) max = ns->outputbuffer.len;
336
337 #ifdef WIN32 /* ***win32 write_socket_buffer: change write() to send() */
338 amt=send(ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max,0);
339 #else
340 do {
341 amt=write(ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max);
342 } while ((amt<0) && (errno==EINTR));
343 #endif
344
345 if (amt < 0) { /* We got an error */
346
347 #ifdef WIN32 /* ***win32 write_socket_buffer: change error handling */
348 if (amt == -1 && WSAGetLastError() !=WSAEWOULDBLOCK) {
349 LOG(llevError,"New socket write failed (wsb) (%d).\n", WSAGetLastError());
350 #else
351 if (errno !=EWOULDBLOCK) {
352 LOG(llevError,"New socket write failed (wsb) (%d: %s).\n",
353 errno, strerror_local(errno));
354 #endif
355 ns->status=Ns_Dead;
356 return;
357 }
358 else { /* EWOULDBLOCK */
359 /* can't write it, so store it away. */
360 ns->can_write=0;
361 return;
362 }
363 }
364 ns->outputbuffer.start += amt;
365 /* wrap back to start of buffer */
366 if (ns->outputbuffer.start==SOCKETBUFSIZE) ns->outputbuffer.start=0;
367 ns->outputbuffer.len -= amt;
368 #ifdef CS_LOGSTATS
369 cst_tot.obytes += amt;
370 cst_lst.obytes += amt;
371 #endif
372 } while (ns->outputbuffer.len>0);
373 }
374
375 /**
376 * This writes data to the socket. - It is very low level -
377 * all we try and do is write out the data to the socket
378 * provided (ns). buf is the data to write, len is the number
379 * of bytes to write. IT doesn't return anything - rather, it
380 * updates the ns structure if we get an error.
381 */
382 void Write_To_Socket(NewSocket *ns, unsigned char *buf, int len)
383 {
384 int amt=0;
385 unsigned char *pos=buf;
386
387 if (ns->status == Ns_Dead || !buf) {
388 LOG(llevDebug,"Write_To_Socket called with dead socket\n");
389 return;
390 }
391
392 #ifndef __GNU__ /* This caused problems on Hurd */
393 if (!ns->can_write) {
394 add_to_buffer(ns, buf, len);
395 return;
396 }
397 #endif
398 /* If we manage to write more than we wanted, take it as a bonus */
399 while (len>0) {
400
401 #ifdef WIN32 /* ***win32 Write_To_Socket: change write() to send() */
402 amt=send(ns->fd, pos, len,0);
403 #else
404 do {
405 amt=write(ns->fd, pos, len);
406 } while ((amt<0) && (errno==EINTR));
407 #endif
408
409 if (amt < 0) { /* We got an error */
410 #ifdef WIN32 /* ***win32 Write_To_Socket: change error handling */
411 if (amt == -1 && WSAGetLastError() !=WSAEWOULDBLOCK) {
412 LOG(llevError,"New socket write failed WTS (%d).\n",WSAGetLastError());
413 #else
414 if (errno !=EWOULDBLOCK) {
415 LOG(llevError,"New socket write failed WTS (%d: %s).\n", /* ---WIN32 */
416 errno, strerror_local(errno));
417 #endif
418 ns->status=Ns_Dead;
419 return;
420 }
421 else { /* EWOULDBLOCK */
422 /* can't write it, so store it away. */
423 add_to_buffer(ns, pos, len);
424 ns->can_write=0;
425 return;
426 }
427 }
428 /* amt gets set to 0 above in blocking code, so we do this as
429 * an else if to make sure we don't reprocess it.
430 */
431 else if (amt==0) {
432 LOG(llevError,"Write_To_Socket: No data written out.\n");
433 }
434 len -= amt;
435 pos += amt;
436 #ifdef CS_LOGSTATS
437 cst_tot.obytes += amt;
438 cst_lst.obytes += amt;
439 #endif
440 }
441 }
442
443
444 /**
445 * Takes a string of data, and writes it out to the socket. A very handy
446 * shortcut function.
447 */
448 void cs_write_string(NewSocket *ns, const char *buf, int len)
449 {
450 SockList sl;
451
452 sl.len = len;
453 sl.buf = (unsigned char*)buf;
454 Send_With_Handling(ns, &sl);
455 }
456
457
458 /**
459 * Calls Write_To_Socket to send data to the client.
460 *
461 * The only difference in this function is that we take a SockList
462 *, and we prepend the length information.
463 */
464 void Send_With_Handling(NewSocket *ns,SockList *msg)
465 {
466 unsigned char sbuf[4];
467
468 if (ns->status == Ns_Dead || !msg)
469 return;
470
471 if (msg->len >= MAXSOCKBUF) {
472 LOG(llevError,"Trying to send a buffer beyond properly size, len =%d\n",
473 msg->len);
474 /* Almost certainly we've overflowed a buffer, so quite now to make
475 * it easier to debug.
476 */
477 abort();
478 }
479 sbuf[0] = ((uint32)(msg->len) >> 8) & 0xFF;
480 sbuf[1] = ((uint32)(msg->len)) & 0xFF;
481 if (ns->status != Ns_Old)
482 Write_To_Socket(ns, sbuf, 2);
483 Write_To_Socket(ns, msg->buf, msg->len);
484 }
485
486 /**
487 * Takes a string of data, and writes it out to the socket. A very handy
488 * shortcut function.
489 */
490 void Write_String_To_Socket(NewSocket *ns, char *buf, int len)
491 {
492 SockList sl;
493
494 sl.len = len;
495 sl.buf = (uint8*)buf;
496 Send_With_Handling(ns, &sl);
497 }
498
499
500 /******************************************************************************
501 *
502 * statistics logging functions.
503 *
504 ******************************************************************************/
505
506 #ifdef CS_LOGSTATS
507 /* cst_tot is for the life of the server, cst_last is for the last series of
508 * stats
509 */
510 CS_Stats cst_tot, cst_lst;
511
512 /**
513 * Writes out the gathered stats. We clear cst_lst.
514 */
515 void write_cs_stats(void)
516 {
517 time_t now=time(NULL);
518
519 /* If no connections recently, don't both to log anything */
520 if (cst_lst.ibytes==0 && cst_lst.obytes==0) return;
521
522 /* CSSTAT is put in so scripts can easily find the line */
523 LOG(llevInfo, "CSSTAT: %.16s tot %d %d %d %d inc %d %d %d %d\n",
524 ctime(&now), cst_tot.ibytes, cst_tot.obytes, cst_tot.max_conn,
525 now - cst_tot.time_start, cst_lst.ibytes, cst_lst.obytes,
526 cst_lst.max_conn, now - cst_lst.time_start);
527 cst_lst.ibytes=0;
528 cst_lst.obytes=0;
529 cst_lst.max_conn=socket_info.nconns;
530 cst_lst.time_start=now;
531 }
532 #endif