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); |
6a578b2c |
50 | ads->tcpsocket= -1; |
620c146d |
51 | ads->tcpstate= server_disconnected; |
70ad7a2a |
52 | ads->tcprecv.used= ads->tcprecv_skip= ads->tcpsend.used= 0; |
620c146d |
53 | ads->tcpserver= (serv+1)%ads->nservers; |
54 | } |
656b2da9 |
55 | |
8402e34c |
56 | void adns__tcp_broken(adns_state ads, const char *what, const char *why) { |
57 | int serv; |
4353a5c4 |
58 | adns_query qu, nqu; |
8402e34c |
59 | |
60 | assert(ads->tcpstate == server_connecting || ads->tcpstate == server_ok); |
ddfda861 |
61 | serv= ads->tcpserver; |
68442019 |
62 | adns__warn(ads,serv,0,"TCP connection lost: %s: %s",what,why); |
620c146d |
63 | adns__tcp_closenext(ads); |
37e28fde |
64 | |
4353a5c4 |
65 | for (qu= ads->timew.head; qu; qu= nqu) { |
8402e34c |
66 | nqu= qu->next; |
d8c062fa |
67 | if (qu->state == query_tosend) continue; |
ddfda861 |
68 | assert(qu->state == query_tcpwait || qu->state == query_tcpsent); |
69 | qu->state= query_tcpwait; |
70 | qu->tcpfailed |= (1<<serv); |
71 | if (qu->tcpfailed == (1<<ads->nservers)-1) { |
4353a5c4 |
72 | LIST_UNLINK(ads->timew,qu); |
3955725c |
73 | adns__query_fail(qu,adns_s_allservfail); |
ddfda861 |
74 | } |
8402e34c |
75 | } |
8402e34c |
76 | } |
77 | |
ddfda861 |
78 | static void tcp_connected(adns_state ads, struct timeval now) { |
4353a5c4 |
79 | adns_query qu, nqu; |
80 | |
68442019 |
81 | adns__debug(ads,ads->tcpserver,0,"TCP connected"); |
4353a5c4 |
82 | ads->tcpstate= server_ok; |
ddfda861 |
83 | for (qu= ads->timew.head; qu; qu= nqu) { |
84 | nqu= qu->next; |
d8c062fa |
85 | if (qu->state == query_tosend) continue; |
ddfda861 |
86 | assert (qu->state == query_tcpwait); |
3955725c |
87 | adns__query_tcp(qu,now); |
ddfda861 |
88 | } |
89 | } |
90 | |
91 | void adns__tcp_tryconnect(adns_state ads, struct timeval now) { |
8402e34c |
92 | int r, fd, tries; |
4353a5c4 |
93 | struct sockaddr_in addr; |
94 | struct protoent *proto; |
8402e34c |
95 | |
96 | for (tries=0; tries<ads->nservers; tries++) { |
97 | if (ads->tcpstate == server_connecting || ads->tcpstate == server_ok) return; |
98 | assert(ads->tcpstate == server_disconnected); |
4353a5c4 |
99 | assert(!ads->tcpsend.used); |
100 | assert(!ads->tcprecv.used); |
70ad7a2a |
101 | assert(!ads->tcprecv_skip); |
8402e34c |
102 | |
103 | proto= getprotobyname("tcp"); |
68442019 |
104 | if (!proto) { adns__diag(ads,-1,0,"unable to find protocol no. for TCP !"); return; } |
8402e34c |
105 | fd= socket(AF_INET,SOCK_STREAM,proto->p_proto); |
4353a5c4 |
106 | if (fd<0) { |
68442019 |
107 | adns__diag(ads,-1,0,"cannot create TCP socket: %s",strerror(errno)); |
4353a5c4 |
108 | return; |
109 | } |
110 | r= adns__setnonblock(ads,fd); |
111 | if (r) { |
68442019 |
112 | adns__diag(ads,-1,0,"cannot make TCP socket nonblocking: %s",strerror(r)); |
4353a5c4 |
113 | close(fd); |
114 | return; |
115 | } |
8402e34c |
116 | memset(&addr,0,sizeof(addr)); |
117 | addr.sin_family= AF_INET; |
98a3f706 |
118 | addr.sin_port= htons(DNS_PORT); |
8402e34c |
119 | addr.sin_addr= ads->servers[ads->tcpserver].addr; |
eec1d9c8 |
120 | r= connect(fd,(const struct sockaddr*)&addr,sizeof(addr)); |
8402e34c |
121 | ads->tcpsocket= fd; |
122 | ads->tcpstate= server_connecting; |
4353a5c4 |
123 | if (r==0) { tcp_connected(ads,now); continue; } |
8402e34c |
124 | if (errno == EWOULDBLOCK || errno == EINPROGRESS) return; |
ddfda861 |
125 | adns__tcp_broken(ads,"connect",strerror(errno)); |
8402e34c |
126 | } |
127 | } |
128 | |
620c146d |
129 | /* Timeout handling functions. */ |
130 | |
131 | void adns__must_gettimeofday(adns_state ads, const struct timeval **now_io, |
132 | struct timeval *tv_buf) { |
133 | const struct timeval *now; |
134 | int r; |
135 | |
136 | now= *now_io; |
137 | if (now) return; |
138 | r= gettimeofday(tv_buf,0); if (!r) { *now_io= tv_buf; return; } |
139 | adns__diag(ads,-1,0,"gettimeofday failed: %s",strerror(errno)); |
140 | adns_globalsystemfailure(ads); |
141 | return; |
142 | } |
4353a5c4 |
143 | |
144 | static void inter_maxto(struct timeval **tv_io, struct timeval *tvbuf, |
145 | struct timeval maxto) { |
146 | struct timeval *rbuf; |
147 | |
148 | if (!tv_io) return; |
149 | rbuf= *tv_io; |
94436798 |
150 | if (!rbuf) { |
151 | *tvbuf= maxto; *tv_io= tvbuf; |
152 | } else { |
153 | if (timercmp(rbuf,&maxto,>)) *rbuf= maxto; |
154 | } |
ffbda80c |
155 | /*fprintf(stderr,"inter_maxto maxto=%ld.%06ld result=%ld.%06ld\n", |
156 | maxto.tv_sec,maxto.tv_usec,(**tv_io).tv_sec,(**tv_io).tv_usec);*/ |
4353a5c4 |
157 | } |
158 | |
159 | static void inter_maxtoabs(struct timeval **tv_io, struct timeval *tvbuf, |
160 | struct timeval now, struct timeval maxtime) { |
161 | ldiv_t dr; |
162 | |
ffbda80c |
163 | /*fprintf(stderr,"inter_maxtoabs now=%ld.%06ld maxtime=%ld.%06ld\n", |
164 | now.tv_sec,now.tv_usec,maxtime.tv_sec,maxtime.tv_usec);*/ |
4353a5c4 |
165 | if (!tv_io) return; |
94436798 |
166 | maxtime.tv_sec -= (now.tv_sec+2); |
167 | maxtime.tv_usec -= (now.tv_usec-2000000); |
168 | dr= ldiv(maxtime.tv_usec,1000000); |
4353a5c4 |
169 | maxtime.tv_sec += dr.quot; |
94436798 |
170 | maxtime.tv_usec -= dr.quot*1000000; |
171 | if (maxtime.tv_sec<0) timerclear(&maxtime); |
4353a5c4 |
172 | inter_maxto(tv_io,tvbuf,maxtime); |
173 | } |
174 | |
620c146d |
175 | void adns__timeouts(adns_state ads, int act, |
176 | struct timeval **tv_io, struct timeval *tvbuf, |
177 | struct timeval now) { |
4353a5c4 |
178 | adns_query qu, nqu; |
620c146d |
179 | |
4353a5c4 |
180 | for (qu= ads->timew.head; qu; qu= nqu) { |
181 | nqu= qu->next; |
d855b532 |
182 | if (!timercmp(&now,&qu->timeout,>)) { |
620c146d |
183 | if (!tv_io) continue; |
184 | inter_maxtoabs(tv_io,tvbuf,now,qu->timeout); |
185 | } else { |
3905bfc2 |
186 | if (!act) { |
6a9f9437 |
187 | tvbuf->tv_sec= 0; |
188 | tvbuf->tv_usec= 0; |
189 | *tv_io= tvbuf; |
3905bfc2 |
190 | return; |
191 | } |
4353a5c4 |
192 | LIST_UNLINK(ads->timew,qu); |
d8c062fa |
193 | if (qu->state != query_tosend) { |
3955725c |
194 | adns__query_fail(qu,adns_s_timeout); |
4353a5c4 |
195 | } else { |
d8c062fa |
196 | adns__query_send(qu,now); |
4353a5c4 |
197 | } |
620c146d |
198 | nqu= ads->timew.head; |
4353a5c4 |
199 | } |
200 | } |
201 | } |
94436798 |
202 | |
620c146d |
203 | void adns_firsttimeout(adns_state ads, |
204 | struct timeval **tv_io, struct timeval *tvbuf, |
205 | struct timeval now) { |
28de6442 |
206 | adns__consistency(ads,0,cc_entex); |
620c146d |
207 | adns__timeouts(ads, 0, tv_io,tvbuf, now); |
28de6442 |
208 | adns__consistency(ads,0,cc_entex); |
620c146d |
209 | } |
210 | |
211 | void adns_processtimeouts(adns_state ads, const struct timeval *now) { |
212 | struct timeval tv_buf; |
213 | |
28de6442 |
214 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
215 | adns__must_gettimeofday(ads,&now,&tv_buf); |
216 | if (now) adns__timeouts(ads, 1, 0,0, *now); |
28de6442 |
217 | adns__consistency(ads,0,cc_entex); |
a8768e80 |
218 | } |
219 | |
620c146d |
220 | /* fd handling functions. These are the top-level of the real work of |
221 | * reception and often transmission. |
222 | */ |
223 | |
224 | int adns__pollfds(adns_state ads, struct pollfd pollfds_buf[MAX_POLLFDS]) { |
225 | /* Returns the number of entries filled in. Always zeroes revents. */ |
226 | |
227 | assert(MAX_POLLFDS==2); |
a8768e80 |
228 | |
620c146d |
229 | pollfds_buf[0].fd= ads->udpsocket; |
230 | pollfds_buf[0].events= POLLIN; |
231 | pollfds_buf[0].revents= 0; |
4353a5c4 |
232 | |
233 | switch (ads->tcpstate) { |
234 | case server_disconnected: |
620c146d |
235 | return 1; |
4353a5c4 |
236 | case server_connecting: |
620c146d |
237 | pollfds_buf[1].events= POLLOUT; |
4353a5c4 |
238 | break; |
239 | case server_ok: |
620c146d |
240 | pollfds_buf[1].events= ads->tcpsend.used ? POLLIN|POLLOUT|POLLPRI : POLLIN|POLLPRI; |
e062dcae |
241 | break; |
4353a5c4 |
242 | default: |
243 | abort(); |
244 | } |
620c146d |
245 | pollfds_buf[1].fd= ads->tcpsocket; |
620c146d |
246 | return 2; |
4353a5c4 |
247 | } |
248 | |
620c146d |
249 | int adns_processreadable(adns_state ads, int fd, const struct timeval *now) { |
70ad7a2a |
250 | int want, dgramlen, r, udpaddrlen, serv, old_skip; |
98a3f706 |
251 | byte udpbuf[DNS_MAXUDP]; |
37e28fde |
252 | struct sockaddr_in udpaddr; |
620c146d |
253 | |
28de6442 |
254 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
255 | |
ddfda861 |
256 | switch (ads->tcpstate) { |
257 | case server_disconnected: |
ddfda861 |
258 | case server_connecting: |
ddfda861 |
259 | break; |
260 | case server_ok: |
620c146d |
261 | if (fd != ads->tcpsocket) break; |
70ad7a2a |
262 | assert(!ads->tcprecv_skip); |
620c146d |
263 | for (;;) { |
70ad7a2a |
264 | if (ads->tcprecv.used >= ads->tcprecv_skip+2) { |
265 | dgramlen= ((ads->tcprecv.buf[ads->tcprecv_skip]<<8) | |
266 | ads->tcprecv.buf[ads->tcprecv_skip+1]); |
267 | if (ads->tcprecv.used >= ads->tcprecv_skip+2+dgramlen) { |
268 | old_skip= ads->tcprecv_skip; |
269 | ads->tcprecv_skip += 2+dgramlen; |
270 | adns__procdgram(ads, ads->tcprecv.buf+old_skip+2, |
271 | dgramlen, ads->tcpserver, 1,*now); |
272 | continue; |
656b2da9 |
273 | } else { |
70ad7a2a |
274 | want= 2+dgramlen; |
656b2da9 |
275 | } |
70ad7a2a |
276 | } else { |
277 | want= 2; |
656b2da9 |
278 | } |
70ad7a2a |
279 | ads->tcprecv.used -= ads->tcprecv_skip; |
280 | memmove(ads->tcprecv.buf,ads->tcprecv.buf+ads->tcprecv_skip,ads->tcprecv.used); |
281 | ads->tcprecv_skip= 0; |
3e2e5fab |
282 | if (!adns__vbuf_ensure(&ads->tcprecv,want)) { r= ENOMEM; goto xit; } |
620c146d |
283 | assert(ads->tcprecv.used <= ads->tcprecv.avail); |
284 | if (ads->tcprecv.used == ads->tcprecv.avail) continue; |
285 | r= read(ads->tcpsocket, |
286 | ads->tcprecv.buf+ads->tcprecv.used, |
287 | ads->tcprecv.avail-ads->tcprecv.used); |
288 | if (r>0) { |
289 | ads->tcprecv.used+= r; |
290 | } else { |
291 | if (r) { |
3e2e5fab |
292 | if (errno==EAGAIN || errno==EWOULDBLOCK) { r= 0; goto xit; } |
620c146d |
293 | if (errno==EINTR) continue; |
3e2e5fab |
294 | if (errno_resources(errno)) { r= errno; goto xit; } |
656b2da9 |
295 | } |
620c146d |
296 | adns__tcp_broken(ads,"read",r?strerror(errno):"closed"); |
3e2e5fab |
297 | r= 0; goto xit; |
656b2da9 |
298 | } |
620c146d |
299 | } /* never reached */ |
ddfda861 |
300 | default: |
301 | abort(); |
656b2da9 |
302 | } |
620c146d |
303 | if (fd == ads->udpsocket) { |
37e28fde |
304 | for (;;) { |
305 | udpaddrlen= sizeof(udpaddr); |
eec1d9c8 |
306 | r= recvfrom(ads->udpsocket,udpbuf,sizeof(udpbuf),0, |
307 | (struct sockaddr*)&udpaddr,&udpaddrlen); |
37e28fde |
308 | if (r<0) { |
3e2e5fab |
309 | if (errno == EAGAIN || errno == EWOULDBLOCK) { r= 0; goto xit; } |
620c146d |
310 | if (errno == EINTR) continue; |
3e2e5fab |
311 | if (errno_resources(errno)) { r= errno; goto xit; } |
620c146d |
312 | adns__warn(ads,-1,0,"datagram receive error: %s",strerror(errno)); |
3e2e5fab |
313 | r= 0; goto xit; |
37e28fde |
314 | } |
315 | if (udpaddrlen != sizeof(udpaddr)) { |
68442019 |
316 | adns__diag(ads,-1,0,"datagram received with wrong address length %d" |
317 | " (expected %d)", udpaddrlen,sizeof(udpaddr)); |
37e28fde |
318 | continue; |
319 | } |
320 | if (udpaddr.sin_family != AF_INET) { |
68442019 |
321 | adns__diag(ads,-1,0,"datagram received with wrong protocol family" |
4353a5c4 |
322 | " %u (expected %u)",udpaddr.sin_family,AF_INET); |
37e28fde |
323 | continue; |
324 | } |
98a3f706 |
325 | if (ntohs(udpaddr.sin_port) != DNS_PORT) { |
68442019 |
326 | adns__diag(ads,-1,0,"datagram received from wrong port %u (expected %u)", |
98a3f706 |
327 | ntohs(udpaddr.sin_port),DNS_PORT); |
37e28fde |
328 | continue; |
329 | } |
330 | for (serv= 0; |
331 | serv < ads->nservers && |
332 | ads->servers[serv].addr.s_addr != udpaddr.sin_addr.s_addr; |
333 | serv++); |
334 | if (serv >= ads->nservers) { |
68442019 |
335 | adns__warn(ads,-1,0,"datagram received from unknown nameserver %s", |
4353a5c4 |
336 | inet_ntoa(udpaddr.sin_addr)); |
37e28fde |
337 | continue; |
338 | } |
ebf4877a |
339 | adns__procdgram(ads,udpbuf,r,serv,0,*now); |
656b2da9 |
340 | } |
37e28fde |
341 | } |
3e2e5fab |
342 | r= 0; |
343 | xit: |
28de6442 |
344 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
345 | return r; |
656b2da9 |
346 | } |
656b2da9 |
347 | |
620c146d |
348 | int adns_processwriteable(adns_state ads, int fd, const struct timeval *now) { |
656b2da9 |
349 | int r; |
620c146d |
350 | |
28de6442 |
351 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
352 | |
620c146d |
353 | switch (ads->tcpstate) { |
354 | case server_disconnected: |
355 | break; |
356 | case server_connecting: |
357 | if (fd != ads->tcpsocket) break; |
358 | assert(ads->tcprecv.used==0); |
70ad7a2a |
359 | assert(ads->tcprecv_skip==0); |
620c146d |
360 | for (;;) { |
3e2e5fab |
361 | if (!adns__vbuf_ensure(&ads->tcprecv,1)) { r= ENOMEM; goto xit; } |
620c146d |
362 | r= read(ads->tcpsocket,&ads->tcprecv.buf,1); |
363 | if (r==0 || (r<0 && (errno==EAGAIN || errno==EWOULDBLOCK))) { |
364 | tcp_connected(ads,*now); |
3e2e5fab |
365 | r= 0; goto xit; |
620c146d |
366 | } |
367 | if (r>0) { |
368 | adns__tcp_broken(ads,"connect/read","sent data before first request"); |
3e2e5fab |
369 | r= 0; goto xit; |
620c146d |
370 | } |
371 | if (errno==EINTR) continue; |
3e2e5fab |
372 | if (errno_resources(errno)) { r= errno; goto xit; } |
620c146d |
373 | adns__tcp_broken(ads,"connect/read",strerror(errno)); |
3e2e5fab |
374 | r= 0; goto xit; |
620c146d |
375 | } /* not reached */ |
376 | case server_ok: |
377 | if (!(ads->tcpsend.used && fd == ads->tcpsocket)) break; |
378 | for (;;) { |
379 | adns__sigpipe_protect(ads); |
380 | r= write(ads->tcpsocket,ads->tcpsend.buf,ads->tcpsend.used); |
381 | adns__sigpipe_unprotect(ads); |
382 | if (r<0) { |
383 | if (errno==EINTR) continue; |
3e2e5fab |
384 | if (errno==EAGAIN || errno==EWOULDBLOCK) { r= 0; goto xit; } |
385 | if (errno_resources(errno)) { r= errno; goto xit; } |
620c146d |
386 | adns__tcp_broken(ads,"write",strerror(errno)); |
3e2e5fab |
387 | r= 0; goto xit; |
620c146d |
388 | } else if (r>0) { |
389 | ads->tcpsend.used -= r; |
390 | memmove(ads->tcpsend.buf,ads->tcpsend.buf+r,ads->tcpsend.used); |
391 | } |
392 | } /* not reached */ |
393 | default: |
394 | abort(); |
395 | } |
3e2e5fab |
396 | r= 0; |
397 | xit: |
28de6442 |
398 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
399 | return r; |
620c146d |
400 | } |
401 | |
402 | int adns_processexceptional(adns_state ads, int fd, const struct timeval *now) { |
28de6442 |
403 | adns__consistency(ads,0,cc_entex); |
620c146d |
404 | switch (ads->tcpstate) { |
405 | case server_disconnected: |
406 | break; |
407 | case server_connecting: |
408 | case server_ok: |
409 | if (fd != ads->tcpsocket) break; |
410 | adns__tcp_broken(ads,"poll/select","exceptional condition detected"); |
3e2e5fab |
411 | break; |
620c146d |
412 | default: |
413 | abort(); |
414 | } |
28de6442 |
415 | adns__consistency(ads,0,cc_entex); |
620c146d |
416 | return 0; |
417 | } |
37e28fde |
418 | |
620c146d |
419 | static void fd_event(adns_state ads, int fd, |
420 | int revent, int pollflag, |
421 | int maxfd, const fd_set *fds, |
422 | int (*func)(adns_state, int fd, const struct timeval *now), |
423 | struct timeval now, int *r_r) { |
656b2da9 |
424 | int r; |
620c146d |
425 | |
426 | if (!(revent & pollflag)) return; |
427 | if (fds && !(fd<maxfd && FD_ISSET(fd,fds))) return; |
428 | r= func(ads,fd,&now); |
429 | if (r) { |
430 | if (r_r) { |
431 | *r_r= r; |
432 | } else { |
433 | adns__diag(ads,-1,0,"process fd failed after select: %s",strerror(errno)); |
434 | adns_globalsystemfailure(ads); |
435 | } |
436 | } |
437 | } |
438 | |
439 | void adns__fdevents(adns_state ads, |
440 | const struct pollfd *pollfds, int npollfds, |
441 | int maxfd, const fd_set *readfds, |
442 | const fd_set *writefds, const fd_set *exceptfds, |
443 | struct timeval now, int *r_r) { |
444 | int i, fd, revents; |
445 | |
446 | for (i=0; i<npollfds; i++) { |
447 | fd= pollfds[i].fd; |
448 | if (fd >= maxfd) maxfd= fd+1; |
449 | revents= pollfds[i].revents; |
450 | fd_event(ads,fd, revents,POLLIN, maxfd,readfds, adns_processreadable,now,r_r); |
451 | fd_event(ads,fd, revents,POLLOUT, maxfd,writefds, adns_processwriteable,now,r_r); |
452 | fd_event(ads,fd, revents,POLLPRI, maxfd,exceptfds, adns_processexceptional,now,r_r); |
453 | } |
454 | } |
37e28fde |
455 | |
620c146d |
456 | /* Wrappers for select(2). */ |
457 | |
458 | void adns_beforeselect(adns_state ads, int *maxfd_io, fd_set *readfds_io, |
459 | fd_set *writefds_io, fd_set *exceptfds_io, |
460 | struct timeval **tv_mod, struct timeval *tv_tobuf, |
461 | const struct timeval *now) { |
462 | struct timeval tv_nowbuf; |
463 | struct pollfd pollfds[MAX_POLLFDS]; |
464 | int i, fd, maxfd, npollfds; |
465 | |
28de6442 |
466 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
467 | |
620c146d |
468 | if (tv_mod && (!*tv_mod || (*tv_mod)->tv_sec || (*tv_mod)->tv_usec)) { |
469 | /* The caller is planning to sleep. */ |
470 | adns__must_gettimeofday(ads,&now,&tv_nowbuf); |
3e2e5fab |
471 | if (!now) goto xit; |
620c146d |
472 | adns__timeouts(ads, 1, tv_mod,tv_tobuf, *now); |
473 | } |
474 | |
475 | npollfds= adns__pollfds(ads,pollfds); |
476 | maxfd= *maxfd_io; |
477 | for (i=0; i<npollfds; i++) { |
478 | fd= pollfds[i].fd; |
479 | if (fd >= maxfd) maxfd= fd+1; |
480 | if (pollfds[i].events & POLLIN) FD_SET(fd,readfds_io); |
481 | if (pollfds[i].events & POLLOUT) FD_SET(fd,writefds_io); |
482 | if (pollfds[i].events & POLLPRI) FD_SET(fd,exceptfds_io); |
483 | } |
484 | *maxfd_io= maxfd; |
3e2e5fab |
485 | |
486 | xit: |
28de6442 |
487 | adns__consistency(ads,0,cc_entex); |
620c146d |
488 | } |
489 | |
490 | void adns_afterselect(adns_state ads, int maxfd, const fd_set *readfds, |
491 | const fd_set *writefds, const fd_set *exceptfds, |
492 | const struct timeval *now) { |
fc6a52ae |
493 | struct timeval tv_buf; |
620c146d |
494 | struct pollfd pollfds[MAX_POLLFDS]; |
fc6a52ae |
495 | int npollfds, i; |
620c146d |
496 | |
28de6442 |
497 | adns__consistency(ads,0,cc_entex); |
fc6a52ae |
498 | adns__must_gettimeofday(ads,&now,&tv_buf); |
3e2e5fab |
499 | if (!now) goto xit; |
620c146d |
500 | adns_processtimeouts(ads,now); |
501 | |
502 | npollfds= adns__pollfds(ads,pollfds); |
fc6a52ae |
503 | for (i=0; i<npollfds; i++) pollfds[i].revents= POLLIN|POLLOUT|POLLPRI; |
620c146d |
504 | adns__fdevents(ads, |
505 | pollfds,npollfds, |
506 | maxfd,readfds,writefds,exceptfds, |
507 | *now, 0); |
3e2e5fab |
508 | xit: |
28de6442 |
509 | adns__consistency(ads,0,cc_entex); |
620c146d |
510 | } |
511 | |
512 | /* General helpful functions. */ |
513 | |
514 | void adns_globalsystemfailure(adns_state ads) { |
28de6442 |
515 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
516 | |
620c146d |
517 | while (ads->timew.head) { |
518 | adns__query_fail(ads->timew.head, adns_s_systemfail); |
519 | } |
520 | |
521 | switch (ads->tcpstate) { |
522 | case server_connecting: |
523 | case server_ok: |
524 | adns__tcp_closenext(ads); |
525 | break; |
526 | case server_disconnected: |
527 | break; |
528 | default: |
529 | abort(); |
530 | } |
28de6442 |
531 | adns__consistency(ads,0,cc_entex); |
656b2da9 |
532 | } |
533 | |
620c146d |
534 | int adns_processany(adns_state ads) { |
aedf10f2 |
535 | int r, i; |
620c146d |
536 | struct timeval now; |
537 | struct pollfd pollfds[MAX_POLLFDS]; |
538 | int npollfds; |
539 | |
28de6442 |
540 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
541 | |
620c146d |
542 | r= gettimeofday(&now,0); |
543 | if (!r) adns_processtimeouts(ads,&now); |
544 | |
25913ee2 |
545 | /* We just use adns__fdevents to loop over the fd's trying them. |
546 | * This seems more sensible than calling select, since we're most |
547 | * likely just to want to do a read on one or two fds anyway. |
548 | */ |
620c146d |
549 | npollfds= adns__pollfds(ads,pollfds); |
aedf10f2 |
550 | for (i=0; i<npollfds; i++) pollfds[i].revents= pollfds[i].events; |
620c146d |
551 | adns__fdevents(ads, |
552 | pollfds,npollfds, |
553 | 0,0,0,0, |
554 | now,&r); |
3e2e5fab |
555 | |
28de6442 |
556 | adns__consistency(ads,0,cc_entex); |
c118a725 |
557 | return 0; |
620c146d |
558 | } |
ddfda861 |
559 | |
4353a5c4 |
560 | void adns__autosys(adns_state ads, struct timeval now) { |
ddfda861 |
561 | if (ads->iflags & adns_if_noautosys) return; |
620c146d |
562 | adns_processany(ads); |
ddfda861 |
563 | } |
564 | |
940356bd |
565 | int adns__internal_check(adns_state ads, |
566 | adns_query *query_io, |
567 | adns_answer **answer, |
568 | void **context_r) { |
656b2da9 |
569 | adns_query qu; |
570 | |
571 | qu= *query_io; |
572 | if (!qu) { |
4ae90a83 |
573 | if (ads->output.head) { |
574 | qu= ads->output.head; |
575 | } else if (ads->timew.head) { |
576 | return EAGAIN; |
577 | } else { |
578 | return ESRCH; |
579 | } |
656b2da9 |
580 | } else { |
226c5eef |
581 | if (qu->id>=0) return EAGAIN; |
656b2da9 |
582 | } |
583 | LIST_UNLINK(ads->output,qu); |
8e5b0abb |
584 | *answer= qu->answer; |
a6536d8b |
585 | if (context_r) *context_r= qu->ctx.ext; |
8ce38e76 |
586 | *query_io= qu; |
656b2da9 |
587 | free(qu); |
588 | return 0; |
589 | } |
590 | |
591 | int adns_wait(adns_state ads, |
592 | adns_query *query_io, |
593 | adns_answer **answer_r, |
594 | void **context_r) { |
620c146d |
595 | int r, maxfd, rsel; |
656b2da9 |
596 | fd_set readfds, writefds, exceptfds; |
597 | struct timeval tvbuf, *tvp; |
598 | |
28de6442 |
599 | adns__consistency(ads,*query_io,cc_entex); |
656b2da9 |
600 | for (;;) { |
940356bd |
601 | r= adns__internal_check(ads,query_io,answer_r,context_r); |
226c5eef |
602 | if (r != EAGAIN) break; |
656b2da9 |
603 | maxfd= 0; tvp= 0; |
37e28fde |
604 | FD_ZERO(&readfds); FD_ZERO(&writefds); FD_ZERO(&exceptfds); |
620c146d |
605 | adns_beforeselect(ads,&maxfd,&readfds,&writefds,&exceptfds,&tvp,&tvbuf,0); |
656b2da9 |
606 | rsel= select(maxfd,&readfds,&writefds,&exceptfds,tvp); |
88372443 |
607 | if (rsel==-1) { |
620c146d |
608 | if (errno == EINTR) { |
3e2e5fab |
609 | if (ads->iflags & adns_if_eintr) { r= EINTR; break; } |
620c146d |
610 | } else { |
611 | adns__diag(ads,-1,0,"select failed in wait: %s",strerror(errno)); |
612 | adns_globalsystemfailure(ads); |
613 | } |
614 | } else { |
615 | assert(rsel >= 0); |
616 | adns_afterselect(ads,maxfd,&readfds,&writefds,&exceptfds,0); |
88372443 |
617 | } |
656b2da9 |
618 | } |
28de6442 |
619 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
620 | return r; |
656b2da9 |
621 | } |
622 | |
623 | int adns_check(adns_state ads, |
624 | adns_query *query_io, |
625 | adns_answer **answer_r, |
626 | void **context_r) { |
4353a5c4 |
627 | struct timeval now; |
628 | int r; |
629 | |
28de6442 |
630 | adns__consistency(ads,*query_io,cc_entex); |
620c146d |
631 | r= gettimeofday(&now,0); |
632 | if (!r) adns__autosys(ads,now); |
3e2e5fab |
633 | |
940356bd |
634 | r= adns__internal_check(ads,query_io,answer_r,context_r); |
28de6442 |
635 | adns__consistency(ads,0,cc_entex); |
3e2e5fab |
636 | return r; |
656b2da9 |
637 | } |