e576be50 |
1 | /* |
2 | * event.c |
3 | * - event loop core |
4 | * - TCP connection management |
5 | * - user-visible check/wait and event-loop-related functions |
6 | */ |
7 | /* |
d942707d |
8 | * This file is |
9 | * Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk> |
10 | * |
11 | * It is part of adns, which is |
12 | * Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk> |
13 | * Copyright (C) 1999 Tony Finch <dot@dotat.at> |
e576be50 |
14 | * |
15 | * This program is free software; you can redistribute it and/or modify |
16 | * it under the terms of the GNU General Public License as published by |
17 | * the Free Software Foundation; either version 2, or (at your option) |
18 | * any later version. |
19 | * |
20 | * This program is distributed in the hope that it will be useful, |
21 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
22 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
23 | * GNU General Public License for more details. |
24 | * |
25 | * You should have received a copy of the GNU General Public License |
26 | * along with this program; if not, write to the Free Software Foundation, |
27 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
28 | */ |
656b2da9 |
29 | |
4353a5c4 |
30 | #include <errno.h> |
31 | #include <stdlib.h> |
0f091044 |
32 | #include <unistd.h> |
4353a5c4 |
33 | |
0f091044 |
34 | #include <sys/types.h> |
35 | #include <sys/time.h> |
4353a5c4 |
36 | #include <netdb.h> |
eec1d9c8 |
37 | #include <sys/socket.h> |
38 | #include <netinet/in.h> |
4353a5c4 |
39 | #include <arpa/inet.h> |
40 | |
41 | #include "internal.h" |
37e28fde |
42 | |
620c146d |
43 | /* TCP connection management. */ |
44 | |
45 | void adns__tcp_closenext(adns_state ads) { |
46 | int serv; |
47 | |
48 | serv= ads->tcpserver; |
49 | close(ads->tcpsocket); |
50 | ads->tcpstate= server_disconnected; |
70ad7a2a |
51 | ads->tcprecv.used= ads->tcprecv_skip= ads->tcpsend.used= 0; |
620c146d |
52 | ads->tcpserver= (serv+1)%ads->nservers; |
53 | } |
656b2da9 |
54 | |
8402e34c |
55 | void adns__tcp_broken(adns_state ads, const char *what, const char *why) { |
56 | int serv; |
4353a5c4 |
57 | adns_query qu, nqu; |
8402e34c |
58 | |
59 | assert(ads->tcpstate == server_connecting || ads->tcpstate == server_ok); |
ddfda861 |
60 | serv= ads->tcpserver; |
68442019 |
61 | adns__warn(ads,serv,0,"TCP connection lost: %s: %s",what,why); |
620c146d |
62 | adns__tcp_closenext(ads); |
37e28fde |
63 | |
4353a5c4 |
64 | for (qu= ads->timew.head; qu; qu= nqu) { |
8402e34c |
65 | nqu= qu->next; |
d8c062fa |
66 | if (qu->state == query_tosend) continue; |
ddfda861 |
67 | assert(qu->state == query_tcpwait || qu->state == query_tcpsent); |
68 | qu->state= query_tcpwait; |
69 | qu->tcpfailed |= (1<<serv); |
70 | if (qu->tcpfailed == (1<<ads->nservers)-1) { |
4353a5c4 |
71 | LIST_UNLINK(ads->timew,qu); |
3955725c |
72 | adns__query_fail(qu,adns_s_allservfail); |
ddfda861 |
73 | } |
8402e34c |
74 | } |
8402e34c |
75 | } |
76 | |
ddfda861 |
77 | static void tcp_connected(adns_state ads, struct timeval now) { |
4353a5c4 |
78 | adns_query qu, nqu; |
79 | |
68442019 |
80 | adns__debug(ads,ads->tcpserver,0,"TCP connected"); |
4353a5c4 |
81 | ads->tcpstate= server_ok; |
ddfda861 |
82 | for (qu= ads->timew.head; qu; qu= nqu) { |
83 | nqu= qu->next; |
d8c062fa |
84 | if (qu->state == query_tosend) continue; |
ddfda861 |
85 | assert (qu->state == query_tcpwait); |
3955725c |
86 | adns__query_tcp(qu,now); |
ddfda861 |
87 | } |
88 | } |
89 | |
90 | void adns__tcp_tryconnect(adns_state ads, struct timeval now) { |
8402e34c |
91 | int r, fd, tries; |
4353a5c4 |
92 | struct sockaddr_in addr; |
93 | struct protoent *proto; |
8402e34c |
94 | |
95 | for (tries=0; tries<ads->nservers; tries++) { |
96 | if (ads->tcpstate == server_connecting || ads->tcpstate == server_ok) return; |
97 | assert(ads->tcpstate == server_disconnected); |
4353a5c4 |
98 | assert(!ads->tcpsend.used); |
99 | assert(!ads->tcprecv.used); |
70ad7a2a |
100 | assert(!ads->tcprecv_skip); |
8402e34c |
101 | |
102 | proto= getprotobyname("tcp"); |
68442019 |
103 | if (!proto) { adns__diag(ads,-1,0,"unable to find protocol no. for TCP !"); return; } |
8402e34c |
104 | fd= socket(AF_INET,SOCK_STREAM,proto->p_proto); |
4353a5c4 |
105 | if (fd<0) { |
68442019 |
106 | adns__diag(ads,-1,0,"cannot create TCP socket: %s",strerror(errno)); |
4353a5c4 |
107 | return; |
108 | } |
109 | r= adns__setnonblock(ads,fd); |
110 | if (r) { |
68442019 |
111 | adns__diag(ads,-1,0,"cannot make TCP socket nonblocking: %s",strerror(r)); |
4353a5c4 |
112 | close(fd); |
113 | return; |
114 | } |
8402e34c |
115 | memset(&addr,0,sizeof(addr)); |
116 | addr.sin_family= AF_INET; |
98a3f706 |
117 | addr.sin_port= htons(DNS_PORT); |
8402e34c |
118 | addr.sin_addr= ads->servers[ads->tcpserver].addr; |
eec1d9c8 |
119 | r= connect(fd,(const struct sockaddr*)&addr,sizeof(addr)); |
8402e34c |
120 | ads->tcpsocket= fd; |
121 | ads->tcpstate= server_connecting; |
4353a5c4 |
122 | if (r==0) { tcp_connected(ads,now); continue; } |
8402e34c |
123 | if (errno == EWOULDBLOCK || errno == EINPROGRESS) return; |
ddfda861 |
124 | adns__tcp_broken(ads,"connect",strerror(errno)); |
8402e34c |
125 | } |
126 | } |
127 | |
620c146d |
128 | /* Timeout handling functions. */ |
129 | |
130 | void adns__must_gettimeofday(adns_state ads, const struct timeval **now_io, |
131 | struct timeval *tv_buf) { |
132 | const struct timeval *now; |
133 | int r; |
134 | |
135 | now= *now_io; |
136 | if (now) return; |
137 | r= gettimeofday(tv_buf,0); if (!r) { *now_io= tv_buf; return; } |
138 | adns__diag(ads,-1,0,"gettimeofday failed: %s",strerror(errno)); |
139 | adns_globalsystemfailure(ads); |
140 | return; |
141 | } |
4353a5c4 |
142 | |
143 | static void inter_maxto(struct timeval **tv_io, struct timeval *tvbuf, |
144 | struct timeval maxto) { |
145 | struct timeval *rbuf; |
146 | |
147 | if (!tv_io) return; |
148 | rbuf= *tv_io; |
94436798 |
149 | if (!rbuf) { |
150 | *tvbuf= maxto; *tv_io= tvbuf; |
151 | } else { |
152 | if (timercmp(rbuf,&maxto,>)) *rbuf= maxto; |
153 | } |
ffbda80c |
154 | /*fprintf(stderr,"inter_maxto maxto=%ld.%06ld result=%ld.%06ld\n", |
155 | maxto.tv_sec,maxto.tv_usec,(**tv_io).tv_sec,(**tv_io).tv_usec);*/ |
4353a5c4 |
156 | } |
157 | |
158 | static void inter_maxtoabs(struct timeval **tv_io, struct timeval *tvbuf, |
159 | struct timeval now, struct timeval maxtime) { |
160 | ldiv_t dr; |
161 | |
ffbda80c |
162 | /*fprintf(stderr,"inter_maxtoabs now=%ld.%06ld maxtime=%ld.%06ld\n", |
163 | now.tv_sec,now.tv_usec,maxtime.tv_sec,maxtime.tv_usec);*/ |
4353a5c4 |
164 | if (!tv_io) return; |
94436798 |
165 | maxtime.tv_sec -= (now.tv_sec+2); |
166 | maxtime.tv_usec -= (now.tv_usec-2000000); |
167 | dr= ldiv(maxtime.tv_usec,1000000); |
4353a5c4 |
168 | maxtime.tv_sec += dr.quot; |
94436798 |
169 | maxtime.tv_usec -= dr.quot*1000000; |
170 | if (maxtime.tv_sec<0) timerclear(&maxtime); |
4353a5c4 |
171 | inter_maxto(tv_io,tvbuf,maxtime); |
172 | } |
173 | |
620c146d |
174 | void adns__timeouts(adns_state ads, int act, |
175 | struct timeval **tv_io, struct timeval *tvbuf, |
176 | struct timeval now) { |
4353a5c4 |
177 | adns_query qu, nqu; |
620c146d |
178 | |
4353a5c4 |
179 | for (qu= ads->timew.head; qu; qu= nqu) { |
180 | nqu= qu->next; |
d855b532 |
181 | if (!timercmp(&now,&qu->timeout,>)) { |
620c146d |
182 | if (!tv_io) continue; |
183 | inter_maxtoabs(tv_io,tvbuf,now,qu->timeout); |
184 | } else { |
185 | if (!act) continue; |
4353a5c4 |
186 | LIST_UNLINK(ads->timew,qu); |
d8c062fa |
187 | if (qu->state != query_tosend) { |
3955725c |
188 | adns__query_fail(qu,adns_s_timeout); |
4353a5c4 |
189 | } else { |
d8c062fa |
190 | adns__query_send(qu,now); |
4353a5c4 |
191 | } |
620c146d |
192 | nqu= ads->timew.head; |
4353a5c4 |
193 | } |
194 | } |
195 | } |
94436798 |
196 | |
620c146d |
197 | void adns_firsttimeout(adns_state ads, |
198 | struct timeval **tv_io, struct timeval *tvbuf, |
199 | struct timeval now) { |
28de6442 |
200 | adns__consistency(ads,0,cc_entex); |
620c146d |
201 | adns__timeouts(ads, 0, tv_io,tvbuf, now); |
28de6442 |
202 | adns__consistency(ads,0,cc_entex); |
620c146d |
203 | } |
204 | |
205 | void adns_processtimeouts(adns_state ads, const struct timeval *now) { |
206 | struct timeval tv_buf; |
207 | |
28de6442 |
208 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
209 | adns__must_gettimeofday(ads,&now,&tv_buf); |
210 | if (now) adns__timeouts(ads, 1, 0,0, *now); |
28de6442 |
211 | adns__consistency(ads,0,cc_entex); |
a8768e80 |
212 | } |
213 | |
620c146d |
214 | /* fd handling functions. These are the top-level of the real work of |
215 | * reception and often transmission. |
216 | */ |
217 | |
218 | int adns__pollfds(adns_state ads, struct pollfd pollfds_buf[MAX_POLLFDS]) { |
219 | /* Returns the number of entries filled in. Always zeroes revents. */ |
220 | |
221 | assert(MAX_POLLFDS==2); |
a8768e80 |
222 | |
620c146d |
223 | pollfds_buf[0].fd= ads->udpsocket; |
224 | pollfds_buf[0].events= POLLIN; |
225 | pollfds_buf[0].revents= 0; |
4353a5c4 |
226 | |
227 | switch (ads->tcpstate) { |
228 | case server_disconnected: |
620c146d |
229 | return 1; |
4353a5c4 |
230 | case server_connecting: |
620c146d |
231 | pollfds_buf[1].events= POLLOUT; |
4353a5c4 |
232 | break; |
233 | case server_ok: |
620c146d |
234 | pollfds_buf[1].events= ads->tcpsend.used ? POLLIN|POLLOUT|POLLPRI : POLLIN|POLLPRI; |
e062dcae |
235 | break; |
4353a5c4 |
236 | default: |
237 | abort(); |
238 | } |
620c146d |
239 | pollfds_buf[1].fd= ads->tcpsocket; |
620c146d |
240 | return 2; |
4353a5c4 |
241 | } |
242 | |
620c146d |
243 | int adns_processreadable(adns_state ads, int fd, const struct timeval *now) { |
70ad7a2a |
244 | int want, dgramlen, r, udpaddrlen, serv, old_skip; |
98a3f706 |
245 | byte udpbuf[DNS_MAXUDP]; |
37e28fde |
246 | struct sockaddr_in udpaddr; |
620c146d |
247 | |
28de6442 |
248 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
249 | |
ddfda861 |
250 | switch (ads->tcpstate) { |
251 | case server_disconnected: |
ddfda861 |
252 | case server_connecting: |
ddfda861 |
253 | break; |
254 | case server_ok: |
620c146d |
255 | if (fd != ads->tcpsocket) break; |
70ad7a2a |
256 | assert(!ads->tcprecv_skip); |
620c146d |
257 | for (;;) { |
70ad7a2a |
258 | if (ads->tcprecv.used >= ads->tcprecv_skip+2) { |
259 | dgramlen= ((ads->tcprecv.buf[ads->tcprecv_skip]<<8) | |
260 | ads->tcprecv.buf[ads->tcprecv_skip+1]); |
261 | if (ads->tcprecv.used >= ads->tcprecv_skip+2+dgramlen) { |
262 | old_skip= ads->tcprecv_skip; |
263 | ads->tcprecv_skip += 2+dgramlen; |
264 | adns__procdgram(ads, ads->tcprecv.buf+old_skip+2, |
265 | dgramlen, ads->tcpserver, 1,*now); |
266 | continue; |
656b2da9 |
267 | } else { |
70ad7a2a |
268 | want= 2+dgramlen; |
656b2da9 |
269 | } |
70ad7a2a |
270 | } else { |
271 | want= 2; |
656b2da9 |
272 | } |
70ad7a2a |
273 | ads->tcprecv.used -= ads->tcprecv_skip; |
274 | memmove(ads->tcprecv.buf,ads->tcprecv.buf+ads->tcprecv_skip,ads->tcprecv.used); |
275 | ads->tcprecv_skip= 0; |
3e2e5fab |
276 | if (!adns__vbuf_ensure(&ads->tcprecv,want)) { r= ENOMEM; goto xit; } |
620c146d |
277 | assert(ads->tcprecv.used <= ads->tcprecv.avail); |
278 | if (ads->tcprecv.used == ads->tcprecv.avail) continue; |
279 | r= read(ads->tcpsocket, |
280 | ads->tcprecv.buf+ads->tcprecv.used, |
281 | ads->tcprecv.avail-ads->tcprecv.used); |
282 | if (r>0) { |
283 | ads->tcprecv.used+= r; |
284 | } else { |
285 | if (r) { |
3e2e5fab |
286 | if (errno==EAGAIN || errno==EWOULDBLOCK) { r= 0; goto xit; } |
620c146d |
287 | if (errno==EINTR) continue; |
3e2e5fab |
288 | if (errno_resources(errno)) { r= errno; goto xit; } |
656b2da9 |
289 | } |
620c146d |
290 | adns__tcp_broken(ads,"read",r?strerror(errno):"closed"); |
3e2e5fab |
291 | r= 0; goto xit; |
656b2da9 |
292 | } |
620c146d |
293 | } /* never reached */ |
ddfda861 |
294 | default: |
295 | abort(); |
656b2da9 |
296 | } |
620c146d |
297 | if (fd == ads->udpsocket) { |
37e28fde |
298 | for (;;) { |
299 | udpaddrlen= sizeof(udpaddr); |
eec1d9c8 |
300 | r= recvfrom(ads->udpsocket,udpbuf,sizeof(udpbuf),0, |
301 | (struct sockaddr*)&udpaddr,&udpaddrlen); |
37e28fde |
302 | if (r<0) { |
3e2e5fab |
303 | if (errno == EAGAIN || errno == EWOULDBLOCK) { r= 0; goto xit; } |
620c146d |
304 | if (errno == EINTR) continue; |
3e2e5fab |
305 | if (errno_resources(errno)) { r= errno; goto xit; } |
620c146d |
306 | adns__warn(ads,-1,0,"datagram receive error: %s",strerror(errno)); |
3e2e5fab |
307 | r= 0; goto xit; |
37e28fde |
308 | } |
309 | if (udpaddrlen != sizeof(udpaddr)) { |
68442019 |
310 | adns__diag(ads,-1,0,"datagram received with wrong address length %d" |
311 | " (expected %d)", udpaddrlen,sizeof(udpaddr)); |
37e28fde |
312 | continue; |
313 | } |
314 | if (udpaddr.sin_family != AF_INET) { |
68442019 |
315 | adns__diag(ads,-1,0,"datagram received with wrong protocol family" |
4353a5c4 |
316 | " %u (expected %u)",udpaddr.sin_family,AF_INET); |
37e28fde |
317 | continue; |
318 | } |
98a3f706 |
319 | if (ntohs(udpaddr.sin_port) != DNS_PORT) { |
68442019 |
320 | adns__diag(ads,-1,0,"datagram received from wrong port %u (expected %u)", |
98a3f706 |
321 | ntohs(udpaddr.sin_port),DNS_PORT); |
37e28fde |
322 | continue; |
323 | } |
324 | for (serv= 0; |
325 | serv < ads->nservers && |
326 | ads->servers[serv].addr.s_addr != udpaddr.sin_addr.s_addr; |
327 | serv++); |
328 | if (serv >= ads->nservers) { |
68442019 |
329 | adns__warn(ads,-1,0,"datagram received from unknown nameserver %s", |
4353a5c4 |
330 | inet_ntoa(udpaddr.sin_addr)); |
37e28fde |
331 | continue; |
332 | } |
ebf4877a |
333 | adns__procdgram(ads,udpbuf,r,serv,0,*now); |
656b2da9 |
334 | } |
37e28fde |
335 | } |
3e2e5fab |
336 | r= 0; |
337 | xit: |
28de6442 |
338 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
339 | return r; |
656b2da9 |
340 | } |
656b2da9 |
341 | |
620c146d |
342 | int adns_processwriteable(adns_state ads, int fd, const struct timeval *now) { |
656b2da9 |
343 | int r; |
620c146d |
344 | |
28de6442 |
345 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
346 | |
620c146d |
347 | switch (ads->tcpstate) { |
348 | case server_disconnected: |
349 | break; |
350 | case server_connecting: |
351 | if (fd != ads->tcpsocket) break; |
352 | assert(ads->tcprecv.used==0); |
70ad7a2a |
353 | assert(ads->tcprecv_skip==0); |
620c146d |
354 | for (;;) { |
3e2e5fab |
355 | if (!adns__vbuf_ensure(&ads->tcprecv,1)) { r= ENOMEM; goto xit; } |
620c146d |
356 | r= read(ads->tcpsocket,&ads->tcprecv.buf,1); |
357 | if (r==0 || (r<0 && (errno==EAGAIN || errno==EWOULDBLOCK))) { |
358 | tcp_connected(ads,*now); |
3e2e5fab |
359 | r= 0; goto xit; |
620c146d |
360 | } |
361 | if (r>0) { |
362 | adns__tcp_broken(ads,"connect/read","sent data before first request"); |
3e2e5fab |
363 | r= 0; goto xit; |
620c146d |
364 | } |
365 | if (errno==EINTR) continue; |
3e2e5fab |
366 | if (errno_resources(errno)) { r= errno; goto xit; } |
620c146d |
367 | adns__tcp_broken(ads,"connect/read",strerror(errno)); |
3e2e5fab |
368 | r= 0; goto xit; |
620c146d |
369 | } /* not reached */ |
370 | case server_ok: |
371 | if (!(ads->tcpsend.used && fd == ads->tcpsocket)) break; |
372 | for (;;) { |
373 | adns__sigpipe_protect(ads); |
374 | r= write(ads->tcpsocket,ads->tcpsend.buf,ads->tcpsend.used); |
375 | adns__sigpipe_unprotect(ads); |
376 | if (r<0) { |
377 | if (errno==EINTR) continue; |
3e2e5fab |
378 | if (errno==EAGAIN || errno==EWOULDBLOCK) { r= 0; goto xit; } |
379 | if (errno_resources(errno)) { r= errno; goto xit; } |
620c146d |
380 | adns__tcp_broken(ads,"write",strerror(errno)); |
3e2e5fab |
381 | r= 0; goto xit; |
620c146d |
382 | } else if (r>0) { |
383 | ads->tcpsend.used -= r; |
384 | memmove(ads->tcpsend.buf,ads->tcpsend.buf+r,ads->tcpsend.used); |
385 | } |
386 | } /* not reached */ |
387 | default: |
388 | abort(); |
389 | } |
3e2e5fab |
390 | r= 0; |
391 | xit: |
28de6442 |
392 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
393 | return r; |
620c146d |
394 | } |
395 | |
396 | int adns_processexceptional(adns_state ads, int fd, const struct timeval *now) { |
28de6442 |
397 | adns__consistency(ads,0,cc_entex); |
620c146d |
398 | switch (ads->tcpstate) { |
399 | case server_disconnected: |
400 | break; |
401 | case server_connecting: |
402 | case server_ok: |
403 | if (fd != ads->tcpsocket) break; |
404 | adns__tcp_broken(ads,"poll/select","exceptional condition detected"); |
3e2e5fab |
405 | break; |
620c146d |
406 | default: |
407 | abort(); |
408 | } |
28de6442 |
409 | adns__consistency(ads,0,cc_entex); |
620c146d |
410 | return 0; |
411 | } |
37e28fde |
412 | |
620c146d |
413 | static void fd_event(adns_state ads, int fd, |
414 | int revent, int pollflag, |
415 | int maxfd, const fd_set *fds, |
416 | int (*func)(adns_state, int fd, const struct timeval *now), |
417 | struct timeval now, int *r_r) { |
656b2da9 |
418 | int r; |
620c146d |
419 | |
420 | if (!(revent & pollflag)) return; |
421 | if (fds && !(fd<maxfd && FD_ISSET(fd,fds))) return; |
422 | r= func(ads,fd,&now); |
423 | if (r) { |
424 | if (r_r) { |
425 | *r_r= r; |
426 | } else { |
427 | adns__diag(ads,-1,0,"process fd failed after select: %s",strerror(errno)); |
428 | adns_globalsystemfailure(ads); |
429 | } |
430 | } |
431 | } |
432 | |
433 | void adns__fdevents(adns_state ads, |
434 | const struct pollfd *pollfds, int npollfds, |
435 | int maxfd, const fd_set *readfds, |
436 | const fd_set *writefds, const fd_set *exceptfds, |
437 | struct timeval now, int *r_r) { |
438 | int i, fd, revents; |
439 | |
440 | for (i=0; i<npollfds; i++) { |
441 | fd= pollfds[i].fd; |
442 | if (fd >= maxfd) maxfd= fd+1; |
443 | revents= pollfds[i].revents; |
444 | fd_event(ads,fd, revents,POLLIN, maxfd,readfds, adns_processreadable,now,r_r); |
445 | fd_event(ads,fd, revents,POLLOUT, maxfd,writefds, adns_processwriteable,now,r_r); |
446 | fd_event(ads,fd, revents,POLLPRI, maxfd,exceptfds, adns_processexceptional,now,r_r); |
447 | } |
448 | } |
37e28fde |
449 | |
620c146d |
450 | /* Wrappers for select(2). */ |
451 | |
452 | void adns_beforeselect(adns_state ads, int *maxfd_io, fd_set *readfds_io, |
453 | fd_set *writefds_io, fd_set *exceptfds_io, |
454 | struct timeval **tv_mod, struct timeval *tv_tobuf, |
455 | const struct timeval *now) { |
456 | struct timeval tv_nowbuf; |
457 | struct pollfd pollfds[MAX_POLLFDS]; |
458 | int i, fd, maxfd, npollfds; |
459 | |
28de6442 |
460 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
461 | |
620c146d |
462 | if (tv_mod && (!*tv_mod || (*tv_mod)->tv_sec || (*tv_mod)->tv_usec)) { |
463 | /* The caller is planning to sleep. */ |
464 | adns__must_gettimeofday(ads,&now,&tv_nowbuf); |
3e2e5fab |
465 | if (!now) goto xit; |
620c146d |
466 | adns__timeouts(ads, 1, tv_mod,tv_tobuf, *now); |
467 | } |
468 | |
469 | npollfds= adns__pollfds(ads,pollfds); |
470 | maxfd= *maxfd_io; |
471 | for (i=0; i<npollfds; i++) { |
472 | fd= pollfds[i].fd; |
473 | if (fd >= maxfd) maxfd= fd+1; |
474 | if (pollfds[i].events & POLLIN) FD_SET(fd,readfds_io); |
475 | if (pollfds[i].events & POLLOUT) FD_SET(fd,writefds_io); |
476 | if (pollfds[i].events & POLLPRI) FD_SET(fd,exceptfds_io); |
477 | } |
478 | *maxfd_io= maxfd; |
3e2e5fab |
479 | |
480 | xit: |
28de6442 |
481 | adns__consistency(ads,0,cc_entex); |
620c146d |
482 | } |
483 | |
484 | void adns_afterselect(adns_state ads, int maxfd, const fd_set *readfds, |
485 | const fd_set *writefds, const fd_set *exceptfds, |
486 | const struct timeval *now) { |
fc6a52ae |
487 | struct timeval tv_buf; |
620c146d |
488 | struct pollfd pollfds[MAX_POLLFDS]; |
fc6a52ae |
489 | int npollfds, i; |
620c146d |
490 | |
28de6442 |
491 | adns__consistency(ads,0,cc_entex); |
fc6a52ae |
492 | adns__must_gettimeofday(ads,&now,&tv_buf); |
3e2e5fab |
493 | if (!now) goto xit; |
620c146d |
494 | adns_processtimeouts(ads,now); |
495 | |
496 | npollfds= adns__pollfds(ads,pollfds); |
fc6a52ae |
497 | for (i=0; i<npollfds; i++) pollfds[i].revents= POLLIN|POLLOUT|POLLPRI; |
620c146d |
498 | adns__fdevents(ads, |
499 | pollfds,npollfds, |
500 | maxfd,readfds,writefds,exceptfds, |
501 | *now, 0); |
3e2e5fab |
502 | xit: |
28de6442 |
503 | adns__consistency(ads,0,cc_entex); |
620c146d |
504 | } |
505 | |
506 | /* General helpful functions. */ |
507 | |
508 | void adns_globalsystemfailure(adns_state ads) { |
28de6442 |
509 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
510 | |
620c146d |
511 | while (ads->timew.head) { |
512 | adns__query_fail(ads->timew.head, adns_s_systemfail); |
513 | } |
514 | |
515 | switch (ads->tcpstate) { |
516 | case server_connecting: |
517 | case server_ok: |
518 | adns__tcp_closenext(ads); |
519 | break; |
520 | case server_disconnected: |
521 | break; |
522 | default: |
523 | abort(); |
524 | } |
28de6442 |
525 | adns__consistency(ads,0,cc_entex); |
656b2da9 |
526 | } |
527 | |
620c146d |
528 | int adns_processany(adns_state ads) { |
529 | int r; |
530 | struct timeval now; |
531 | struct pollfd pollfds[MAX_POLLFDS]; |
532 | int npollfds; |
533 | |
28de6442 |
534 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
535 | |
620c146d |
536 | r= gettimeofday(&now,0); |
537 | if (!r) adns_processtimeouts(ads,&now); |
538 | |
25913ee2 |
539 | /* We just use adns__fdevents to loop over the fd's trying them. |
540 | * This seems more sensible than calling select, since we're most |
541 | * likely just to want to do a read on one or two fds anyway. |
542 | */ |
620c146d |
543 | npollfds= adns__pollfds(ads,pollfds); |
544 | adns__fdevents(ads, |
545 | pollfds,npollfds, |
546 | 0,0,0,0, |
547 | now,&r); |
3e2e5fab |
548 | |
28de6442 |
549 | adns__consistency(ads,0,cc_entex); |
c118a725 |
550 | return 0; |
620c146d |
551 | } |
ddfda861 |
552 | |
4353a5c4 |
553 | void adns__autosys(adns_state ads, struct timeval now) { |
ddfda861 |
554 | if (ads->iflags & adns_if_noautosys) return; |
620c146d |
555 | adns_processany(ads); |
ddfda861 |
556 | } |
557 | |
940356bd |
558 | int adns__internal_check(adns_state ads, |
559 | adns_query *query_io, |
560 | adns_answer **answer, |
561 | void **context_r) { |
656b2da9 |
562 | adns_query qu; |
563 | |
564 | qu= *query_io; |
565 | if (!qu) { |
566 | if (!ads->output.head) return EWOULDBLOCK; |
567 | qu= ads->output.head; |
568 | } else { |
569 | if (qu->id>=0) return EWOULDBLOCK; |
570 | } |
571 | LIST_UNLINK(ads->output,qu); |
8e5b0abb |
572 | *answer= qu->answer; |
a6536d8b |
573 | if (context_r) *context_r= qu->ctx.ext; |
8ce38e76 |
574 | *query_io= qu; |
656b2da9 |
575 | free(qu); |
576 | return 0; |
577 | } |
578 | |
579 | int adns_wait(adns_state ads, |
580 | adns_query *query_io, |
581 | adns_answer **answer_r, |
582 | void **context_r) { |
620c146d |
583 | int r, maxfd, rsel; |
656b2da9 |
584 | fd_set readfds, writefds, exceptfds; |
585 | struct timeval tvbuf, *tvp; |
586 | |
28de6442 |
587 | adns__consistency(ads,*query_io,cc_entex); |
656b2da9 |
588 | for (;;) { |
940356bd |
589 | r= adns__internal_check(ads,query_io,answer_r,context_r); |
3e2e5fab |
590 | if (r != EWOULDBLOCK) break; |
656b2da9 |
591 | maxfd= 0; tvp= 0; |
37e28fde |
592 | FD_ZERO(&readfds); FD_ZERO(&writefds); FD_ZERO(&exceptfds); |
620c146d |
593 | adns_beforeselect(ads,&maxfd,&readfds,&writefds,&exceptfds,&tvp,&tvbuf,0); |
656b2da9 |
594 | rsel= select(maxfd,&readfds,&writefds,&exceptfds,tvp); |
88372443 |
595 | if (rsel==-1) { |
620c146d |
596 | if (errno == EINTR) { |
3e2e5fab |
597 | if (ads->iflags & adns_if_eintr) { r= EINTR; break; } |
620c146d |
598 | } else { |
599 | adns__diag(ads,-1,0,"select failed in wait: %s",strerror(errno)); |
600 | adns_globalsystemfailure(ads); |
601 | } |
602 | } else { |
603 | assert(rsel >= 0); |
604 | adns_afterselect(ads,maxfd,&readfds,&writefds,&exceptfds,0); |
88372443 |
605 | } |
656b2da9 |
606 | } |
28de6442 |
607 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
608 | return r; |
656b2da9 |
609 | } |
610 | |
611 | int adns_check(adns_state ads, |
612 | adns_query *query_io, |
613 | adns_answer **answer_r, |
614 | void **context_r) { |
4353a5c4 |
615 | struct timeval now; |
616 | int r; |
617 | |
28de6442 |
618 | adns__consistency(ads,*query_io,cc_entex); |
620c146d |
619 | r= gettimeofday(&now,0); |
620 | if (!r) adns__autosys(ads,now); |
3e2e5fab |
621 | |
940356bd |
622 | r= adns__internal_check(ads,query_io,answer_r,context_r); |
28de6442 |
623 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
624 | return r; |
656b2da9 |
625 | } |