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5580185e | 1 | /* |
2 | * $Source$ | |
3 | * $Header$ | |
4 | */ | |
5 | ||
6 | #ifndef lint | |
7 | static char *rcsid_gdb_conn_c = "$Header$"; | |
8 | #endif lint | |
9 | ||
10 | ||
11 | ||
12 | ||
13 | ||
14 | ||
15 | ||
16 | ||
17 | ||
18 | ||
19 | ||
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21 | ||
22 | ||
23 | ||
24 | ||
25 | ||
26 | ||
27 | ||
28 | ||
29 | ||
30 | ||
31 | ||
32 | ||
33 | /************************************************************************/ | |
34 | /* | |
35 | /* gdb_conn.c | |
36 | /* | |
37 | /* GDB - Connection Management Services | |
38 | /* | |
39 | /* Author: Noah Mendelsohn | |
40 | /* Copyright: 1986 MIT Project Athena | |
0a5ff702 | 41 | /* For copying and distribution information, please see |
42 | /* the file <mit-copyright.h>. | |
5580185e | 43 | /* |
44 | /* Routines used in the creation and maintenance of CONNECTIONS. | |
45 | /* Note: these are closely related to the services provided | |
46 | /* by gdb_trans.c and gdb_trans2.c. | |
47 | /* | |
48 | /* | |
49 | /************************************************************************/ | |
50 | ||
0a5ff702 | 51 | #include <mit-copyright.h> |
5580185e | 52 | #include <stdio.h> |
53 | #include <strings.h> | |
54 | #include "gdb.h" | |
55 | #include <sys/types.h> | |
56 | #include <sys/uio.h> | |
57 | #include <sys/socket.h> | |
58 | #include <sys/ioctl.h> | |
59 | #include <netinet/in.h> | |
60 | #include <netdb.h> | |
61 | #include <errno.h> | |
62 | ||
63 | extern int errno; | |
64 | #ifdef vax | |
65 | extern u_short htons(); /* ?? All versions? */ | |
66 | #endif vax | |
67 | ||
68 | CONNECTION gdb_allocate_connection(); | |
69 | ||
70 | /************************************************************************/ | |
71 | /* | |
72 | /* start_peer_connection (start_peer_connection) | |
73 | /* | |
74 | /* Starts a connection to another process which itself will be | |
75 | /* issuing a start_peer_connection to us. Current implementation | |
76 | /* builds at most one stream, with the risk of a hang if | |
77 | /* the attempts to connect cross in the night. This is a bug, | |
78 | /* but this level of support is acceptable for casual debugging | |
79 | /* of applications, and perhaps for some production use in | |
80 | /* controlled settings. I think the only other way to do it | |
81 | /* is to risk building two streams in parallel, possibly tearing | |
82 | /* one down when the duplication is discovered. Seems complicated | |
83 | /* and messy. | |
84 | /* | |
85 | /************************************************************************/ | |
86 | ||
87 | CONNECTION | |
88 | start_peer_connection(id) | |
89 | char *id; /* null terminated string */ | |
90 | { | |
91 | register CONNECTION con; /* the connection we're */ | |
92 | /* creating */ | |
93 | ||
94 | GDB_INIT_CHECK | |
95 | ||
96 | /* | |
97 | * Try to allocate a connection and fill it in with null values. | |
98 | */ | |
99 | ||
100 | con = g_make_con(); | |
101 | ||
102 | /* | |
103 | * In this implementation, we use a single fd for both inbound and | |
104 | * outbound traffic. Try to connect to other side. If that | |
105 | * doesn't work, wait to accept a connection from the other side. | |
106 | * Current implementation of this is synchronous--may be a problem? | |
107 | * Also note timing window bug in the following. If the two peers | |
108 | * are started at just about the same time, the race may not be handled | |
109 | * propoerly. If the connections come up, then verify the level of | |
110 | * protocol being observed on the connections. If incompatible, | |
111 | * then turn off the connection. | |
112 | */ | |
113 | ||
114 | if(!g_try_connecting(con,id)) { | |
115 | g_try_accepting(con,id); | |
116 | if(con->status == CON_STARTING) | |
117 | g_ver_iprotocol(con); | |
118 | } else | |
119 | if(con->status == CON_STARTING) | |
120 | g_ver_oprotocol(con); | |
121 | ||
122 | ||
123 | if (con->status == CON_UP) { | |
124 | /* | |
125 | * We've successfully started the connection, now mark | |
126 | * it for non-blocking I/O. Also, update the high water | |
127 | * mark of fd's controlled by our system. | |
128 | */ | |
129 | int nb = 1; | |
130 | if(ioctl(con->in.fd, FIONBIO, (char *)&nb)== (-1)) { | |
131 | g_stop_with_errno(con); | |
132 | return con; | |
133 | } | |
134 | if (con->in.fd +1 > gdb_mfd) | |
135 | gdb_mfd = con->in.fd + 1; | |
136 | /* | |
137 | * Allocate a buffer, if necessary, and reset buffer pointers | |
138 | * so first request will result in a long read into the buffer | |
139 | */ | |
140 | g_allocate_connection_buffers(con); | |
141 | ||
142 | return con; | |
143 | } else | |
144 | return NULL; | |
145 | } | |
146 | \f | |
147 | /************************************************************************/ | |
148 | /* | |
149 | /* g_make_con | |
150 | /* | |
151 | /* Internal routine to allocate a new connection structure and | |
152 | /* initialize all its fields to logical null values. | |
153 | /* | |
154 | /************************************************************************/ | |
155 | ||
156 | CONNECTION | |
157 | g_make_con() | |
158 | { | |
159 | register CONNECTION con; | |
160 | ||
161 | /* | |
162 | * Try to allocate a connection, fatal error if none available | |
163 | */ | |
164 | con = gdb_allocate_connection(); | |
165 | if (con == NULL) | |
166 | GDB_GIVEUP("start_peer_connection: Tried to allocate too many connections") /* <==RECOVERABLE */ | |
167 | ||
168 | /* | |
169 | * Give the fields their initial values | |
170 | */ | |
171 | g_null_con(con); | |
172 | ||
173 | return con; | |
174 | ||
175 | } | |
176 | ||
177 | \f/************************************************************************/ | |
178 | /* | |
179 | /* g_null_con | |
180 | /* | |
181 | /* Sets a connection descriptor to have all null values in | |
182 | /* its fields. This routine does NOT do any of the cleanup | |
183 | /* which is necessary after the connection has really been used. | |
184 | /* | |
185 | /************************************************************************/ | |
186 | ||
187 | int | |
188 | g_null_con(con) | |
189 | CONNECTION con; | |
190 | { | |
191 | /* | |
192 | * Initialize the connection control data structure. | |
193 | */ | |
194 | con->id = GDB_CON_ID; | |
195 | con->status = CON_STARTING; | |
196 | con->oob_fcn = NULL; /* out of band signalling */ | |
197 | /* is not currently */ | |
198 | /* implemented */ | |
199 | con->errno = 0; /* system errno gets */ | |
200 | /* copied here iff it */ | |
201 | /* causes this con to die */ | |
202 | /* | |
203 | * Initialize input half connection to null state before trying | |
204 | * to bring it up. | |
205 | */ | |
206 | con->in.status = OP_NOT_STARTED; | |
207 | con->in.fd = -1; | |
208 | con->in.oob_fd = -1; | |
209 | con->in.op_q_first = (struct oper_data *)&con->in; | |
210 | con->in.op_q_last = (struct oper_data *)&con->in; | |
211 | con->in.next_byte = NULL; | |
212 | con->in.remaining = 0; | |
213 | con->in.flags = 0; | |
214 | ||
215 | /* | |
216 | * Initialize output half connection to null state before trying | |
217 | * to bring it up. | |
218 | */ | |
219 | con->out.status = OP_NOT_STARTED; | |
220 | con->out.fd = -1; | |
221 | con->out.oob_fd = -1; | |
222 | con->out.op_q_first = (struct oper_data *)&con->out; | |
223 | con->out.op_q_last = (struct oper_data *)&con->out; | |
224 | con->out.next_byte = NULL; | |
225 | con->out.remaining = 0; | |
226 | con->out.flags = 0; | |
227 | ||
228 | return; | |
229 | ||
230 | } | |
231 | ||
232 | \f | |
233 | /************************************************************************/ | |
234 | /* | |
235 | /* gdb_allocate_connection | |
236 | /* | |
237 | /* Return an unused entry in the connection array. Unused entries | |
238 | /* are recognized by being marked as CON_STOPPED. | |
239 | /* | |
240 | /* Note that gdb_mcons is the number of descriptors which have | |
241 | /* ever been used (i.e. a high water mark), so status fields | |
242 | /* are invalid above that. | |
243 | /* | |
244 | /************************************************************************/ | |
245 | ||
246 | CONNECTION | |
247 | gdb_allocate_connection() | |
248 | { | |
249 | register int i; /* index of next one */ | |
250 | /* to check */ | |
251 | ||
252 | /* | |
253 | * First look for one below the high water mark | |
254 | */ | |
255 | for(i=0; i<gdb_mcons; i++) { | |
256 | if (gdb_cons[i].status == CON_STOPPED) | |
257 | return &gdb_cons[i]; | |
258 | } | |
259 | ||
260 | /* | |
261 | * Allocate one which has never been used, if possible | |
262 | */ | |
263 | ||
264 | if (i>=GDB_MAX_CONNECTIONS) | |
265 | GDB_GIVEUP("gdb: tried to allocate too many simulataneous connections.\n, See GDB_MAX_CONNECTIONS in gdb.h.") /* <==RECOVERABLE */ | |
266 | ||
267 | gdb_mcons++; /* bump the high water mark */ | |
268 | gdb_cons[i].status = CON_STOPPED; /* initialize status of the */ | |
269 | /* new connection */ | |
270 | return &gdb_cons[i]; /* return new highest con */ | |
271 | /* ever used*/ | |
272 | } | |
273 | \f | |
274 | /************************************************************************/ | |
275 | /* | |
276 | /* g_try_connecting | |
277 | /* | |
278 | /* Try to start a connection to the designated site, filling | |
279 | /* in the appropriate information in the connection descriptor | |
280 | /* if successful. Return TRUE if connection succeeded or if | |
281 | /* error was fatal enough that we shouldn't try accepting. Returns | |
282 | /* FALSE if we should try accepting. | |
283 | /* | |
284 | /************************************************************************/ | |
285 | ||
286 | int | |
287 | ||
288 | g_try_connecting(con,id) | |
289 | CONNECTION con; | |
290 | char *id; | |
291 | { | |
292 | int peer; /* socket for talking to | |
293 | peer */ | |
294 | struct sockaddr_in target; /* build the peer address */ | |
295 | /* here */ | |
296 | struct hostent *peer_host; /* host where peer is */ | |
297 | ||
298 | /*----------------------------------------------------------*/ | |
299 | /* | |
300 | /* Make sure connection is marked stopped until we | |
301 | /* get it going. | |
302 | /* | |
303 | /*----------------------------------------------------------*/ | |
304 | ||
305 | con->status = CON_STOPPED; | |
306 | ||
307 | /*----------------------------------------------------------*/ | |
308 | /* | |
309 | /* Find out host where peer is, and validate it. Take | |
310 | /* care of port at the same time. | |
311 | /* | |
312 | /*----------------------------------------------------------*/ | |
313 | ||
314 | bzero((char *)&target, sizeof(target)); | |
315 | g_parse_target(id, &peer_host, &target.sin_port); | |
316 | if (peer_host == NULL) { | |
317 | fprintf(gdb_log,"gdb: g_try_connecting... '%s' is not a valid host:server\n", | |
318 | id); | |
319 | return TRUE; /* so we won't try accepting */ | |
320 | } | |
321 | ||
322 | /*----------------------------------------------------------*/ | |
323 | /* | |
324 | /* Create a socket | |
325 | /* | |
326 | /*----------------------------------------------------------*/ | |
327 | ||
328 | peer = socket(AF_INET, SOCK_STREAM, 0); | |
329 | if (peer < 0) { | |
330 | g_stop_with_errno(con); | |
331 | return TRUE; /* fatal error */ | |
332 | } | |
333 | ||
334 | /*----------------------------------------------------------*/ | |
335 | /* | |
336 | /* Get information and bind socket using well known | |
337 | /* port (BUG: this restricts us to one pair of peers | |
338 | /* per host pair, as well as being bad practice on | |
339 | /* the network. It will do for debugging. | |
340 | /* | |
341 | /*----------------------------------------------------------*/ | |
342 | ||
343 | ||
344 | bcopy(peer_host->h_addr, (char *)&target.sin_addr, peer_host->h_length); | |
345 | target.sin_family = peer_host->h_addrtype; | |
346 | ||
347 | /*----------------------------------------------------------*/ | |
348 | /* | |
349 | /* Make the connection | |
350 | /* | |
351 | /*----------------------------------------------------------*/ | |
352 | ||
353 | if(connect(peer, (struct sockaddr *)&target, sizeof(target)) < 0) { | |
354 | if (errno == ECONNREFUSED) | |
355 | return FALSE; /* other side not yet */ | |
356 | /* up, but no other fatal */ | |
357 | /* errors*/ | |
358 | else { | |
359 | gdb_perror("gdb: unexpected error connecting"); | |
360 | g_stop_with_errno(con); | |
361 | return TRUE; | |
362 | } | |
363 | } | |
364 | ||
365 | /*----------------------------------------------------------*/ | |
366 | /* | |
367 | /* The connection has been made, fill in the connection | |
368 | /* control data structure. | |
369 | /* | |
370 | /*----------------------------------------------------------*/ | |
371 | ||
372 | con->in.fd = peer; | |
373 | con->out.fd = peer; | |
374 | con->status = CON_STARTING; | |
375 | ||
376 | return TRUE; | |
377 | ||
378 | } | |
379 | \f | |
380 | /************************************************************************/ | |
381 | /* | |
382 | /* g_parse_target | |
383 | /* | |
384 | /* For a given server or peer i.d., figure out the host and the | |
385 | /* port. Arguments are: | |
386 | /* | |
387 | /* string i.d. of the server, which is | |
388 | /* in one of two forms: | |
389 | /* | |
390 | /* host:servicename (where service name must not begin | |
391 | /* with #) | |
392 | /* | |
393 | /* host:#portnumber (where portnumber is the actual | |
394 | /* number of the port to be used) | |
395 | /* | |
396 | /* (actually, a 3rd form, with no port number supplied, | |
397 | /* will use a default GDB_PORT, but this is unsafe | |
398 | /* and it will be disabled in production versions | |
399 | /* of the gdb system.) | |
400 | /* | |
401 | /* **hostent: returned to indicate host to be used. Null | |
402 | /* if host could not be found | |
403 | /* | |
404 | /* *port pointer to an integer where the port number will | |
405 | /* be put. We return the port number in network | |
406 | /* byte order. | |
407 | /* | |
408 | /************************************************************************/ | |
409 | ||
410 | int | |
411 | g_parse_target(id, host, port) | |
412 | char *id; | |
413 | struct hostent **host; | |
414 | u_short *port; | |
415 | { | |
416 | char buffer[256]; /* longest host name */ | |
417 | register char *ip, *bp; /* for copying name */ | |
418 | struct servent *serv; /* returned from */ | |
419 | /* get service by name */ | |
420 | ||
421 | /*----------------------------------------------------------*/ | |
422 | /* | |
423 | /* copy the host name part only to local buffer | |
424 | /* | |
425 | /*----------------------------------------------------------*/ | |
426 | ||
427 | ip = id; | |
428 | bp = buffer; | |
429 | ||
430 | while (*ip != '\0' && *ip != ':') | |
431 | *bp++ = *ip++; | |
432 | *bp = '\0'; | |
433 | ||
434 | /*----------------------------------------------------------*/ | |
435 | /* | |
436 | /* Look up the host name, return if bad. | |
437 | /* | |
438 | /*----------------------------------------------------------*/ | |
439 | ||
440 | *host = gethostbyname(buffer); | |
441 | ||
442 | if (*host == NULL) | |
443 | return; | |
444 | ||
445 | /*----------------------------------------------------------*/ | |
446 | /* | |
447 | /* Set up the port address | |
448 | /* | |
449 | /*----------------------------------------------------------*/ | |
450 | ||
451 | if (*ip++ != ':') { | |
452 | *port = GDB_PORT; | |
453 | return; | |
454 | } | |
455 | ||
456 | if (*ip == '\0') { | |
457 | *host = NULL; | |
458 | return; | |
459 | } | |
460 | ||
461 | if (*ip == '#') { | |
462 | /* | |
463 | * port number supplied explictly | |
464 | */ | |
465 | ip++; | |
466 | if (*ip < '0' || *ip>'9') { | |
467 | *host = NULL; | |
468 | return; | |
469 | } | |
470 | *port = htons((u_short)atoi(ip)); | |
471 | } else { | |
472 | /* | |
473 | * service identified by name | |
474 | */ | |
475 | serv = getservbyname(ip, "tcp"); | |
476 | if (serv == NULL) { | |
477 | *host = NULL; | |
478 | return; | |
479 | } | |
480 | *port = serv->s_port; | |
481 | } | |
482 | } | |
483 | \f | |
484 | /************************************************************************/ | |
485 | /* | |
486 | /* g_try_accepting | |
487 | /* | |
488 | /* Try to accept a connection to the designated site, filling | |
489 | /* in the appropriate information in the connection descriptor | |
490 | /* if successful. | |
491 | /* | |
492 | /************************************************************************/ | |
493 | ||
494 | int | |
495 | g_try_accepting(con,id) | |
496 | CONNECTION con; | |
497 | char *id; | |
498 | { | |
499 | int slisten; /* socket on which | |
500 | we listen for connections */ | |
501 | ||
502 | int peer; /* socket for talking to | |
503 | peer */ | |
504 | int fromlen; | |
505 | struct sockaddr_in self, from; | |
506 | int retries = GDB_BIND_RETRY_COUNT; | |
507 | int onoff = 1; /* used as argument to */ | |
508 | /* setsockopt */ | |
509 | ||
510 | struct hostent *peer_host; /* host where peer is */ | |
511 | ||
512 | /*----------------------------------------------------------*/ | |
513 | /* | |
514 | /* Make sure connection is marked stopped until we | |
515 | /* get it going. | |
516 | /* | |
517 | /*----------------------------------------------------------*/ | |
518 | ||
519 | con->status = CON_STOPPED; | |
520 | ||
521 | /*----------------------------------------------------------*/ | |
522 | /* | |
523 | /* Create a socket on which to listen. Tell it that | |
524 | /* it's OK to re-use the port address, which may still | |
525 | /* appear busy if connections are taking awhile to go | |
526 | /* away. | |
527 | /* | |
528 | /*----------------------------------------------------------*/ | |
529 | ||
530 | slisten = socket(AF_INET, SOCK_STREAM, 0); | |
531 | if (slisten < 0) { | |
532 | gdb_perror("g_try_accepting: error creating listen socket"); | |
533 | g_stop_with_errno(con); | |
534 | } | |
535 | /* Try 4.2 method */ | |
536 | if(setsockopt(slisten, SOL_SOCKET, SO_REUSEADDR, (char *)0, 0)<0) | |
537 | /* that didn't work, try 4.3 */ | |
538 | if(setsockopt(slisten, SOL_SOCKET, SO_REUSEADDR, | |
539 | (char *)&onoff, sizeof(int)) <0) | |
540 | GDB_GIVEUP("g_try_accepting: could not set SO_REUSEADDR"); | |
541 | ||
542 | /*----------------------------------------------------------*/ | |
543 | /* | |
544 | /* Find out host where peer is, and validate it. Take | |
545 | /* care of port at the same time. This is redundant | |
546 | /* given that g_try_connecting is always called first. | |
547 | /* | |
548 | /*----------------------------------------------------------*/ | |
549 | ||
550 | bzero((char *)&self, sizeof(self)); | |
551 | g_parse_target(id, &peer_host, &self.sin_port); | |
552 | if (peer_host == NULL) { | |
553 | GDB_GIVEUP("gdb_try_accepting: bad port not caught by try connecting") | |
554 | } | |
555 | ||
556 | /*----------------------------------------------------------*/ | |
557 | /* | |
558 | /* Bind the socket to ourselves, using the well known | |
559 | /* port (See bug note in g_try_connecting. | |
560 | /* | |
561 | /* This code should really go in initialization, I think. | |
562 | /* | |
563 | /*----------------------------------------------------------*/ | |
564 | ||
565 | while (bind(slisten,(struct sockaddr *)&self,sizeof(self)) < 0) { | |
566 | if (errno == EADDRINUSE && retries--) { | |
567 | fprintf(gdb_log,"gdb: port address in use, will retry %d more time(s)\n",retries+1); | |
568 | sleep(GDB_BIND_RETRY_INTERVAL); | |
569 | continue; | |
570 | } else { | |
571 | gdb_perror("gdb: error binding listen socket"); | |
572 | g_stop_with_errno(con); | |
573 | (void) close(slisten); | |
574 | return; | |
575 | } | |
576 | } | |
577 | ||
578 | /*----------------------------------------------------------*/ | |
579 | /* | |
580 | /* Listen for connections. | |
581 | /* | |
582 | /*----------------------------------------------------------*/ | |
583 | ||
584 | (void) listen (slisten, 5); /* does not block, just */ | |
585 | /* sets the maximum backlog */ | |
586 | /* of pending non-accepted */ | |
587 | /* cons.*/ | |
588 | fromlen = sizeof(from); | |
589 | peer = accept(slisten, &from, &fromlen); | |
590 | if (peer < 0) { | |
591 | g_stop_with_errno(con); | |
592 | gdb_perror("gdb_try_accepting: error accepting connection"); | |
593 | (void) close(slisten); | |
594 | return; | |
595 | } | |
596 | ||
597 | (void) close (slisten); /* we're not using the */ | |
598 | /* listening socket */ | |
599 | /* anymore, only the */ | |
600 | /* connection to the peer */ | |
601 | ||
602 | /*----------------------------------------------------------*/ | |
603 | /* | |
604 | /* The connection has been made, fill in the connection | |
605 | /* control data structure. | |
606 | /* | |
607 | /*----------------------------------------------------------*/ | |
608 | ||
609 | con->in.fd = peer; | |
610 | con->out.fd = peer; | |
611 | con->status = CON_STARTING; | |
612 | } | |
613 | \f | |
614 | /************************************************************************/ | |
615 | /* | |
616 | /* g_ver_oprotocol | |
617 | /* | |
618 | /* Called when an outbound connection is started to verify | |
619 | /* the version of the protocol being observed. | |
620 | /* | |
621 | /************************************************************************/ | |
622 | ||
623 | int | |
624 | g_ver_oprotocol(con) | |
625 | CONNECTION con; | |
626 | { | |
627 | #ifdef VERIFY_PROTOCOL | |
628 | char ver = GDB_PROTOCOL_VERSION; | |
629 | char theirs; | |
630 | int len; | |
631 | ||
632 | int onoff = 0; /* for ioctl to turn off */ | |
633 | ||
634 | /* | |
635 | * Because the connection was accepted on a non-blocking | |
636 | * listening socket, the connection itself may be non-blocking. | |
637 | * We can't tolerate that here. It will be reset later. | |
638 | */ | |
639 | if (ioctl(con->in.fd, FIONBIO, (char *)&onoff) < 0) { | |
640 | g_stop_with_errno(con); | |
641 | gdb_perror("Can't turn off FIONBIO in g_ver_iprotocol"); | |
642 | return; | |
643 | } | |
644 | ||
645 | while (write(con->out.fd, &ver, 1) < 0) { | |
646 | g_stop_with_errno(con); | |
647 | return; | |
648 | } | |
649 | ||
650 | do { | |
651 | len = read(con->in.fd, &theirs, 1); | |
652 | if (len == (-1)) { | |
653 | g_stop_with_errno(con); | |
654 | return; | |
655 | } | |
656 | } while (len !=1); | |
657 | ||
658 | if (theirs == ver) | |
659 | con->status = CON_UP; | |
660 | else | |
661 | con->status = CON_STOPPED; | |
662 | #else !VERIFY_PROTOCOL | |
663 | con->status = CON_UP; | |
664 | #endif !VERIFY_PROTOCOL | |
665 | } | |
666 | ||
667 | /************************************************************************/ | |
668 | /* | |
669 | /* g_ver_iprotocol | |
670 | /* | |
671 | /* Called when an inbound connection is started to verify | |
672 | /* the version of the protocol being observed. | |
673 | /* | |
674 | /************************************************************************/ | |
675 | ||
676 | int | |
677 | g_ver_iprotocol(con) | |
678 | CONNECTION con; | |
679 | { | |
680 | #ifdef VERIFY_PROTOCOL | |
681 | char ver = GDB_PROTOCOL_VERSION; | |
682 | char theirs; | |
683 | int len; | |
684 | int old_nbio; | |
685 | int onoff = 0; /* for ioctl to turn off */ | |
686 | ||
687 | /* | |
688 | * Because the connection was accepted on a non-blocking | |
689 | * listening socket, the connection itself may be non-blocking. | |
690 | * We can't tolerate that here. It will be reset later. | |
691 | */ | |
692 | if (ioctl(con->in.fd, FIONBIO, (char *)&onoff) < 0) { | |
693 | g_stop_with_errno(con); | |
694 | gdb_perror("Can't turn off FIONBIO in g_ver_iprotocol"); | |
695 | return; | |
696 | } | |
697 | ||
698 | do { | |
699 | len = read(con->in.fd, &theirs, 1); | |
700 | if (len == (-1)) { | |
701 | g_stop_with_errno(con); | |
702 | return; | |
703 | } | |
704 | } while (len !=1) ; | |
705 | ||
706 | if (theirs == ver) | |
707 | con->status = CON_UP; | |
708 | else | |
709 | con->status = CON_STOPPED; | |
710 | ||
711 | while (write(con->out.fd, &ver, 1) < 0) { | |
712 | g_stop_with_errno(con); | |
713 | return; | |
714 | } | |
715 | #else !VERIFY_PROTOCOL | |
716 | con->status = CON_UP; | |
717 | #endif | |
718 | } | |
719 | ||
720 | \f | |
721 | /************************************************************************/ | |
722 | /* | |
723 | /* sever_connection (sever_connection) | |
724 | /* | |
725 | /* Unconditionally, but cleanly, terminates a connection. All | |
726 | /* pending operations on the connection are cancelled, and the | |
727 | /* file descriptor for the connection is closed. This routine | |
728 | /* should be called directly from applications wishing to shut | |
729 | /* down a connection. No transmissions are attempted | |
730 | /* by this routine. Returns NULL, in the hope that applications | |
731 | /* will assign this to their old CONNECTION variable. | |
732 | /* | |
733 | /************************************************************************/ | |
734 | ||
735 | CONNECTION | |
736 | sever_connection(con) | |
737 | CONNECTION con; | |
738 | { | |
739 | if (con == NULL) | |
740 | return NULL; | |
741 | GDB_CHECK_CON(con, "sever_connection") | |
742 | if (con->status == CON_UP || con->status == CON_STARTING) | |
743 | g_stop_connection(con); | |
744 | if (con->status != CON_STOPPED) | |
745 | gdb_de_allocate_connection(con); | |
746 | ||
747 | return NULL; | |
748 | } | |
749 | ||
750 | /************************************************************************/ | |
751 | /* | |
752 | /* g_stop_with_errno | |
753 | /* | |
754 | /* This connection is stopping because of a problem on a syscall. | |
755 | /* We record the errno in the connection descriptor for inspection | |
756 | /* by the application, then stop the connection. | |
757 | /* | |
758 | /************************************************************************/ | |
759 | ||
760 | ||
761 | int | |
762 | g_stop_with_errno(con) | |
763 | CONNECTION con; | |
764 | { | |
765 | con->errno = errno; | |
766 | g_stop_connection(con); | |
767 | ||
768 | } | |
769 | ||
770 | /************************************************************************/ | |
771 | /* | |
772 | /* g_stop_connection | |
773 | /* | |
774 | /* Unconditionally, but cleanly, terminates a connection. All | |
775 | /* pending operations on the connection are cancelled, and the | |
776 | /* file descriptor for the connection is closed. This routine is | |
777 | /* for internal use. Applications call sever_connection, which | |
778 | /* also de_allocates the descriptor. No transmissions are attempted | |
779 | /* by this routine. | |
780 | /* | |
781 | /************************************************************************/ | |
782 | ||
783 | int | |
784 | g_stop_connection(con) | |
785 | CONNECTION con; | |
786 | { | |
787 | /* | |
788 | * Shutdown activity on the two half connections. | |
789 | */ | |
790 | g_cleanup_half_connection(&(con->in)); | |
791 | g_cleanup_half_connection(&(con->out)); | |
792 | ||
793 | /* | |
794 | * Remove the file descriptor from the select bit maps | |
795 | */ | |
e3b289f4 | 796 | if (!(con->in.flags & HCON_UNUSED) && con->in.fd >= 0) |
5580185e | 797 | FD_CLR(con->in.fd, &gdb_crfds); |
e3b289f4 | 798 | if (!(con->out.flags & HCON_UNUSED) && con->out.fd >= 0) |
5580185e | 799 | FD_CLR(con->out.fd, &gdb_cwfds); |
800 | /* | |
801 | * Close the file descriptor. Note, this presumes that in fact | |
802 | * 1) in is never the unused half and | |
803 | * 2) when the connection is bi-directional, in and out share an | |
804 | * fd. We could do with a more elaborate scheme to control | |
805 | * this in the future. | |
806 | */ | |
807 | (void) close(con->in.fd); | |
808 | ||
809 | /* | |
810 | * Mark the connection as stopping. We can't reclaim the | |
811 | * descriptor until the application does a sever, or else there | |
812 | * would be a risk of re-allocating it out from under the application. | |
813 | */ | |
814 | ||
815 | con->status = CON_STOPPING; | |
816 | ||
817 | return; | |
818 | } | |
819 | ||
820 | \f | |
821 | /************************************************************************/ | |
822 | /* | |
823 | /* gdb_de_allocate_connection | |
824 | /* | |
825 | /* Return a connection whose file descriptors have been closed | |
826 | /* to the pool. | |
827 | /* | |
828 | /************************************************************************/ | |
829 | ||
830 | int | |
831 | gdb_de_allocate_connection(con) | |
832 | CONNECTION con; | |
833 | { | |
834 | register int i; | |
835 | ||
836 | con->status = CON_STOPPED; | |
837 | ||
838 | i = gdb_mcons-1; /* start at last one used */ | |
839 | ||
840 | /* | |
841 | * Reset gdb_mcons to be the number of connections in use | |
842 | */ | |
843 | while (i>=0 && gdb_cons[i].status == CON_STOPPED) | |
844 | i--; | |
845 | ||
846 | gdb_mcons = i + 1; | |
847 | } | |
848 | \f | |
849 | /************************************************************************/ | |
850 | /* | |
851 | /* g_cleanup_half_conection | |
852 | /* | |
853 | /* Terminate all pending operations on the supplied half | |
854 | /* connection. Note that the algorithm used here presumes | |
855 | /* that cancel_operation will de-queue the operation descriptor, | |
856 | /* therefore we have to be careful here about when we look at | |
857 | /* chain pointers. | |
858 | /* | |
859 | /************************************************************************/ | |
860 | ||
861 | int | |
862 | g_cleanup_half_connection(hcon) | |
863 | HALF_CONNECTION hcon; | |
864 | { | |
865 | OPERATION current, next; | |
866 | ||
867 | current = hcon->op_q_first; | |
868 | ||
869 | /* | |
870 | * Loop through all operations in the queue canceling them. | |
871 | * Make sure to pick up pointer to 'next' before the current | |
872 | * one is canceled, as cancelling may invalidate the pointer. | |
873 | */ | |
874 | ||
875 | while (current != (OPERATION)hcon) { | |
876 | next = current->next; | |
877 | (void) cancel_operation(current); | |
878 | current = next; | |
879 | } | |
880 | } | |
881 | \f | |
882 | /************************************************************************/ | |
883 | /* | |
884 | /* create_listening_connection (create_listening_connection) | |
885 | /* | |
886 | /* Starts a special type of connection which is used to listen | |
887 | /* for incoming connection requests. The inbound half-connection | |
888 | /* is the only one used for this special kind of connection. | |
889 | /* | |
890 | /* It is the user's responsibility to insure that only appropriate | |
891 | /* types of operation are queued on a connection of this sort. In | |
892 | /* general, these connections are intended for internal use by | |
893 | /* GDB, and they are not intended to be visible to servers or | |
894 | /* clients directly. | |
895 | /* | |
896 | /* The id supplied should be in one of two forms. If just a | |
897 | /* string is supplied then it is presumed to be the name of | |
898 | /* a registered tcp service. If the name begins with a #, then | |
899 | /* the rest is interpreted as the integer port number to be used. | |
900 | /* | |
901 | /* In future implementations, the id may have more structure, which | |
902 | /* is why we define it as a string. | |
903 | /* | |
904 | /************************************************************************/ | |
905 | ||
906 | CONNECTION | |
907 | create_listening_connection(id) | |
908 | char *id; | |
909 | { | |
910 | register CONNECTION con; /* the connection we're */ | |
911 | /* creating */ | |
912 | ||
913 | register int slisten; /* socket on which | |
914 | we listen for connections */ | |
915 | ||
916 | struct sockaddr_in self; | |
917 | int retries = GDB_BIND_RETRY_COUNT; | |
918 | int onoff = 1; /* used as argument to */ | |
919 | /* setsockopt */ | |
920 | struct servent *serv; | |
921 | ||
922 | GDB_INIT_CHECK | |
923 | ||
924 | /* | |
925 | * Try to allocate a connection and fill it in with null values. | |
926 | */ | |
927 | ||
928 | con = g_make_con(); | |
929 | ||
930 | /* | |
931 | * Try to create a socket for listening | |
932 | */ | |
933 | con->in.fd = socket(AF_INET, SOCK_STREAM, 0); | |
934 | slisten = con->in.fd; /* easier and faster than */ | |
935 | /* using con->in.fd all the */ | |
936 | /* time*/ | |
937 | if (slisten < 0 ) { | |
938 | gdb_perror("create_listening_connection: error creating listen socket"); | |
939 | (void) g_stop_with_errno(con); | |
940 | return con; | |
941 | } | |
942 | /* | |
943 | * Set options so the listening address can be re-used (this | |
944 | * has its dangers, but otherwise we can't restart our servers | |
945 | * for long periods after they crash because of connections which | |
946 | * take a long to time clean up and hold ports in use.) | |
947 | */ | |
948 | ||
949 | /* Try 4.2 method */ | |
950 | if(setsockopt(slisten, SOL_SOCKET, SO_REUSEADDR, (char *)0,0)<0) | |
951 | /* that didn't work, try 4.3 */ | |
952 | if(setsockopt(slisten, SOL_SOCKET, SO_REUSEADDR, | |
953 | (char *)&onoff, sizeof(int)) <0) | |
954 | GDB_GIVEUP("create_listening_connection: could not set SO_REUSEADDR") | |
955 | ; | |
956 | /* | |
957 | * Make the listening socket non-blocking so we won't have to do | |
958 | * selects before polling it (change made by Bill Sommerfeld - wesommer) | |
959 | */ | |
960 | if (ioctl(slisten, FIONBIO, (char *)&onoff) < 0) { /*<==FIX,,,add comment */ | |
961 | g_stop_with_errno(con); | |
962 | gdb_perror("ioctl for listening socket"); | |
963 | return con; | |
964 | } | |
965 | /*----------------------------------------------------------*/ | |
966 | /* | |
967 | /* Bind the socket to ourselves, using port derived from | |
968 | /* the supplied id string. | |
969 | /* | |
970 | /*----------------------------------------------------------*/ | |
971 | ||
972 | bzero((char *)&self, sizeof(self)); | |
973 | /* | |
974 | * Determine our port number | |
975 | */ | |
976 | if (*id == '#') | |
977 | self.sin_port = htons((u_short)atoi(id+1)); | |
978 | else { | |
979 | serv = getservbyname(id, "tcp"); | |
980 | if (serv == NULL) { | |
981 | fprintf(gdb_log,"gdb create_listening_connection: cannot become service named %s\n",id); | |
982 | return NULL; /* BUG: causes connetion */ | |
983 | /* descriptor leakage. Should */ | |
984 | /* return an error code in */ | |
985 | /* the connection descriptor*/ | |
986 | } | |
987 | self.sin_port = serv->s_port; | |
988 | ||
989 | } | |
990 | /* | |
991 | * Try and re-try the bind until it works or until retry count | |
992 | * is exhausted. | |
993 | */ | |
994 | while (bind(slisten,(struct sockaddr *)&self,sizeof(self)) < 0) { | |
995 | if (errno == EADDRINUSE && retries--) { | |
996 | fprintf(gdb_log,"gdb create_listening_connection: port address in use, will retry %d more time(s)\n",retries+1); | |
997 | sleep(GDB_BIND_RETRY_INTERVAL); | |
998 | continue; | |
999 | } else { | |
1000 | gdb_perror("gdb create_listening_connection: error binding listen socket"); | |
1001 | g_stop_with_errno(con); | |
1002 | return con; | |
1003 | } | |
1004 | } | |
1005 | ||
1006 | /*----------------------------------------------------------*/ | |
1007 | /* | |
1008 | /* Listen for connections. | |
1009 | /* | |
1010 | /*----------------------------------------------------------*/ | |
1011 | ||
1012 | (void) listen (slisten, 5); /* does not block, just */ | |
1013 | /* sets the maximum backlog */ | |
1014 | /* of pending non-accepted */ | |
1015 | /* cons.*/ | |
1016 | ||
1017 | con->in.flags |= HCON_LISTEN; | |
1018 | con->out.flags |= HCON_UNUSED; | |
1019 | con->status = CON_UP; | |
1020 | if (con->in.fd +1 > gdb_mfd) | |
1021 | gdb_mfd = con->in.fd + 1; | |
1022 | return con; | |
1023 | } | |
1024 | \f | |
1025 | /************************************************************************/ | |
1026 | /* | |
1027 | /* g_allocate_connection_buffers | |
1028 | /* | |
1029 | /* Create a buffer which can be used to receive large | |
1030 | /* chunks of data from the socket. This is currently done only | |
1031 | /* on the inbound half connection. Also, the buffers are not freed | |
1032 | /* once allocated, even if the connection descriptor is re-used. | |
1033 | /* | |
1034 | /************************************************************************/ | |
1035 | ||
1036 | int | |
1037 | g_allocate_connection_buffers(con) | |
1038 | CONNECTION con; | |
1039 | { | |
1040 | HALF_CONNECTION inbound = &(con->in); | |
1041 | ||
1042 | /* | |
1043 | * See if there is already one allocated, if not, allocate one. | |
1044 | */ | |
1045 | if (inbound->stream_buffer == (char *)NULL) { | |
1046 | inbound->stream_buffer = | |
1047 | db_alloc(inbound->stream_buffer_length); | |
1048 | } | |
1049 | ||
1050 | /* | |
1051 | * In any case, make sure that it is effectively empty | |
1052 | */ | |
1053 | inbound -> stream_buffer_next = inbound -> stream_buffer; | |
1054 | inbound -> stream_buffer_remaining = 0; | |
1055 | } |