98db6da3 |
1 | /* |
2 | * event.c |
3 | * - event loop core |
4 | * - TCP connection management |
5 | * - user-visible check/wait and event-loop-related functions |
6 | */ |
7 | /* |
a79ac5ba |
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> |
98db6da3 |
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 | */ |
6f17710a |
29 | |
d05cc330 |
30 | #include <errno.h> |
31 | #include <stdlib.h> |
b6b3ac61 |
32 | #include <unistd.h> |
d05cc330 |
33 | |
b6b3ac61 |
34 | #include <sys/types.h> |
35 | #include <sys/time.h> |
d05cc330 |
36 | #include <netdb.h> |
29cf9c44 |
37 | #include <sys/socket.h> |
38 | #include <netinet/in.h> |
d05cc330 |
39 | #include <arpa/inet.h> |
40 | |
41 | #include "internal.h" |
dfdbb32c |
42 | |
74c94831 |
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); |
e70d5929 |
50 | ads->tcpsocket= -1; |
74c94831 |
51 | ads->tcpstate= server_disconnected; |
ab898cf4 |
52 | ads->tcprecv.used= ads->tcprecv_skip= ads->tcpsend.used= 0; |
74c94831 |
53 | ads->tcpserver= (serv+1)%ads->nservers; |
54 | } |
6f17710a |
55 | |
71324651 |
56 | void adns__tcp_broken(adns_state ads, const char *what, const char *why) { |
57 | int serv; |
d05cc330 |
58 | adns_query qu, nqu; |
71324651 |
59 | |
60 | assert(ads->tcpstate == server_connecting || ads->tcpstate == server_ok); |
96e79df5 |
61 | serv= ads->tcpserver; |
ae41e040 |
62 | adns__warn(ads,serv,0,"TCP connection lost: %s: %s",what,why); |
74c94831 |
63 | adns__tcp_closenext(ads); |
dfdbb32c |
64 | |
d05cc330 |
65 | for (qu= ads->timew.head; qu; qu= nqu) { |
71324651 |
66 | nqu= qu->next; |
24d52b13 |
67 | if (qu->state == query_tosend) continue; |
96e79df5 |
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) { |
d05cc330 |
72 | LIST_UNLINK(ads->timew,qu); |
11c8bf9b |
73 | adns__query_fail(qu,adns_s_allservfail); |
96e79df5 |
74 | } |
71324651 |
75 | } |
71324651 |
76 | } |
77 | |
96e79df5 |
78 | static void tcp_connected(adns_state ads, struct timeval now) { |
d05cc330 |
79 | adns_query qu, nqu; |
80 | |
ae41e040 |
81 | adns__debug(ads,ads->tcpserver,0,"TCP connected"); |
d05cc330 |
82 | ads->tcpstate= server_ok; |
96e79df5 |
83 | for (qu= ads->timew.head; qu; qu= nqu) { |
84 | nqu= qu->next; |
24d52b13 |
85 | if (qu->state == query_tosend) continue; |
96e79df5 |
86 | assert (qu->state == query_tcpwait); |
11c8bf9b |
87 | adns__query_tcp(qu,now); |
96e79df5 |
88 | } |
89 | } |
90 | |
91 | void adns__tcp_tryconnect(adns_state ads, struct timeval now) { |
71324651 |
92 | int r, fd, tries; |
d05cc330 |
93 | struct sockaddr_in addr; |
94 | struct protoent *proto; |
71324651 |
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); |
d05cc330 |
99 | assert(!ads->tcpsend.used); |
100 | assert(!ads->tcprecv.used); |
ab898cf4 |
101 | assert(!ads->tcprecv_skip); |
71324651 |
102 | |
103 | proto= getprotobyname("tcp"); |
ae41e040 |
104 | if (!proto) { adns__diag(ads,-1,0,"unable to find protocol no. for TCP !"); return; } |
71324651 |
105 | fd= socket(AF_INET,SOCK_STREAM,proto->p_proto); |
d05cc330 |
106 | if (fd<0) { |
ae41e040 |
107 | adns__diag(ads,-1,0,"cannot create TCP socket: %s",strerror(errno)); |
d05cc330 |
108 | return; |
109 | } |
110 | r= adns__setnonblock(ads,fd); |
111 | if (r) { |
ae41e040 |
112 | adns__diag(ads,-1,0,"cannot make TCP socket nonblocking: %s",strerror(r)); |
d05cc330 |
113 | close(fd); |
114 | return; |
115 | } |
71324651 |
116 | memset(&addr,0,sizeof(addr)); |
117 | addr.sin_family= AF_INET; |
5c596e4d |
118 | addr.sin_port= htons(DNS_PORT); |
71324651 |
119 | addr.sin_addr= ads->servers[ads->tcpserver].addr; |
29cf9c44 |
120 | r= connect(fd,(const struct sockaddr*)&addr,sizeof(addr)); |
71324651 |
121 | ads->tcpsocket= fd; |
122 | ads->tcpstate= server_connecting; |
d05cc330 |
123 | if (r==0) { tcp_connected(ads,now); continue; } |
71324651 |
124 | if (errno == EWOULDBLOCK || errno == EINPROGRESS) return; |
96e79df5 |
125 | adns__tcp_broken(ads,"connect",strerror(errno)); |
71324651 |
126 | } |
127 | } |
128 | |
74c94831 |
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 | } |
d05cc330 |
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; |
de8b18da |
150 | if (!rbuf) { |
151 | *tvbuf= maxto; *tv_io= tvbuf; |
152 | } else { |
153 | if (timercmp(rbuf,&maxto,>)) *rbuf= maxto; |
154 | } |
cfdca685 |
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);*/ |
d05cc330 |
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 | |
cfdca685 |
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);*/ |
d05cc330 |
165 | if (!tv_io) return; |
de8b18da |
166 | maxtime.tv_sec -= (now.tv_sec+2); |
167 | maxtime.tv_usec -= (now.tv_usec-2000000); |
168 | dr= ldiv(maxtime.tv_usec,1000000); |
d05cc330 |
169 | maxtime.tv_sec += dr.quot; |
de8b18da |
170 | maxtime.tv_usec -= dr.quot*1000000; |
171 | if (maxtime.tv_sec<0) timerclear(&maxtime); |
d05cc330 |
172 | inter_maxto(tv_io,tvbuf,maxtime); |
173 | } |
174 | |
74c94831 |
175 | void adns__timeouts(adns_state ads, int act, |
176 | struct timeval **tv_io, struct timeval *tvbuf, |
177 | struct timeval now) { |
d05cc330 |
178 | adns_query qu, nqu; |
74c94831 |
179 | |
d05cc330 |
180 | for (qu= ads->timew.head; qu; qu= nqu) { |
181 | nqu= qu->next; |
7def4935 |
182 | if (!timercmp(&now,&qu->timeout,>)) { |
74c94831 |
183 | if (!tv_io) continue; |
184 | inter_maxtoabs(tv_io,tvbuf,now,qu->timeout); |
185 | } else { |
186 | if (!act) continue; |
d05cc330 |
187 | LIST_UNLINK(ads->timew,qu); |
24d52b13 |
188 | if (qu->state != query_tosend) { |
11c8bf9b |
189 | adns__query_fail(qu,adns_s_timeout); |
d05cc330 |
190 | } else { |
24d52b13 |
191 | adns__query_send(qu,now); |
d05cc330 |
192 | } |
74c94831 |
193 | nqu= ads->timew.head; |
d05cc330 |
194 | } |
195 | } |
196 | } |
de8b18da |
197 | |
74c94831 |
198 | void adns_firsttimeout(adns_state ads, |
199 | struct timeval **tv_io, struct timeval *tvbuf, |
200 | struct timeval now) { |
2ac463bf |
201 | adns__consistency(ads,0,cc_entex); |
74c94831 |
202 | adns__timeouts(ads, 0, tv_io,tvbuf, now); |
2ac463bf |
203 | adns__consistency(ads,0,cc_entex); |
74c94831 |
204 | } |
205 | |
206 | void adns_processtimeouts(adns_state ads, const struct timeval *now) { |
207 | struct timeval tv_buf; |
208 | |
2ac463bf |
209 | adns__consistency(ads,0,cc_entex); |
1389dc72 |
210 | adns__must_gettimeofday(ads,&now,&tv_buf); |
211 | if (now) adns__timeouts(ads, 1, 0,0, *now); |
2ac463bf |
212 | adns__consistency(ads,0,cc_entex); |
74c94831 |
213 | } |
214 | |
215 | /* fd handling functions. These are the top-level of the real work of |
216 | * reception and often transmission. |
217 | */ |
218 | |
219 | int adns__pollfds(adns_state ads, struct pollfd pollfds_buf[MAX_POLLFDS]) { |
220 | /* Returns the number of entries filled in. Always zeroes revents. */ |
221 | |
222 | assert(MAX_POLLFDS==2); |
223 | |
224 | pollfds_buf[0].fd= ads->udpsocket; |
225 | pollfds_buf[0].events= POLLIN; |
226 | pollfds_buf[0].revents= 0; |
d05cc330 |
227 | |
228 | switch (ads->tcpstate) { |
229 | case server_disconnected: |
74c94831 |
230 | return 1; |
d05cc330 |
231 | case server_connecting: |
74c94831 |
232 | pollfds_buf[1].events= POLLOUT; |
d05cc330 |
233 | break; |
234 | case server_ok: |
74c94831 |
235 | pollfds_buf[1].events= ads->tcpsend.used ? POLLIN|POLLOUT|POLLPRI : POLLIN|POLLPRI; |
f2ad23ee |
236 | break; |
d05cc330 |
237 | default: |
238 | abort(); |
239 | } |
74c94831 |
240 | pollfds_buf[1].fd= ads->tcpsocket; |
74c94831 |
241 | return 2; |
d05cc330 |
242 | } |
243 | |
74c94831 |
244 | int adns_processreadable(adns_state ads, int fd, const struct timeval *now) { |
ab898cf4 |
245 | int want, dgramlen, r, udpaddrlen, serv, old_skip; |
5c596e4d |
246 | byte udpbuf[DNS_MAXUDP]; |
dfdbb32c |
247 | struct sockaddr_in udpaddr; |
74c94831 |
248 | |
2ac463bf |
249 | adns__consistency(ads,0,cc_entex); |
1389dc72 |
250 | |
96e79df5 |
251 | switch (ads->tcpstate) { |
252 | case server_disconnected: |
96e79df5 |
253 | case server_connecting: |
96e79df5 |
254 | break; |
255 | case server_ok: |
74c94831 |
256 | if (fd != ads->tcpsocket) break; |
ab898cf4 |
257 | assert(!ads->tcprecv_skip); |
74c94831 |
258 | for (;;) { |
ab898cf4 |
259 | if (ads->tcprecv.used >= ads->tcprecv_skip+2) { |
260 | dgramlen= ((ads->tcprecv.buf[ads->tcprecv_skip]<<8) | |
261 | ads->tcprecv.buf[ads->tcprecv_skip+1]); |
262 | if (ads->tcprecv.used >= ads->tcprecv_skip+2+dgramlen) { |
263 | old_skip= ads->tcprecv_skip; |
264 | ads->tcprecv_skip += 2+dgramlen; |
265 | adns__procdgram(ads, ads->tcprecv.buf+old_skip+2, |
266 | dgramlen, ads->tcpserver, 1,*now); |
267 | continue; |
6f17710a |
268 | } else { |
ab898cf4 |
269 | want= 2+dgramlen; |
6f17710a |
270 | } |
ab898cf4 |
271 | } else { |
272 | want= 2; |
6f17710a |
273 | } |
ab898cf4 |
274 | ads->tcprecv.used -= ads->tcprecv_skip; |
275 | memmove(ads->tcprecv.buf,ads->tcprecv.buf+ads->tcprecv_skip,ads->tcprecv.used); |
276 | ads->tcprecv_skip= 0; |
1389dc72 |
277 | if (!adns__vbuf_ensure(&ads->tcprecv,want)) { r= ENOMEM; goto xit; } |
74c94831 |
278 | assert(ads->tcprecv.used <= ads->tcprecv.avail); |
279 | if (ads->tcprecv.used == ads->tcprecv.avail) continue; |
280 | r= read(ads->tcpsocket, |
281 | ads->tcprecv.buf+ads->tcprecv.used, |
282 | ads->tcprecv.avail-ads->tcprecv.used); |
283 | if (r>0) { |
284 | ads->tcprecv.used+= r; |
285 | } else { |
286 | if (r) { |
1389dc72 |
287 | if (errno==EAGAIN || errno==EWOULDBLOCK) { r= 0; goto xit; } |
74c94831 |
288 | if (errno==EINTR) continue; |
1389dc72 |
289 | if (errno_resources(errno)) { r= errno; goto xit; } |
6f17710a |
290 | } |
74c94831 |
291 | adns__tcp_broken(ads,"read",r?strerror(errno):"closed"); |
1389dc72 |
292 | r= 0; goto xit; |
6f17710a |
293 | } |
74c94831 |
294 | } /* never reached */ |
96e79df5 |
295 | default: |
296 | abort(); |
6f17710a |
297 | } |
74c94831 |
298 | if (fd == ads->udpsocket) { |
dfdbb32c |
299 | for (;;) { |
300 | udpaddrlen= sizeof(udpaddr); |
29cf9c44 |
301 | r= recvfrom(ads->udpsocket,udpbuf,sizeof(udpbuf),0, |
302 | (struct sockaddr*)&udpaddr,&udpaddrlen); |
dfdbb32c |
303 | if (r<0) { |
1389dc72 |
304 | if (errno == EAGAIN || errno == EWOULDBLOCK) { r= 0; goto xit; } |
74c94831 |
305 | if (errno == EINTR) continue; |
1389dc72 |
306 | if (errno_resources(errno)) { r= errno; goto xit; } |
74c94831 |
307 | adns__warn(ads,-1,0,"datagram receive error: %s",strerror(errno)); |
1389dc72 |
308 | r= 0; goto xit; |
dfdbb32c |
309 | } |
310 | if (udpaddrlen != sizeof(udpaddr)) { |
ae41e040 |
311 | adns__diag(ads,-1,0,"datagram received with wrong address length %d" |
312 | " (expected %d)", udpaddrlen,sizeof(udpaddr)); |
dfdbb32c |
313 | continue; |
314 | } |
315 | if (udpaddr.sin_family != AF_INET) { |
ae41e040 |
316 | adns__diag(ads,-1,0,"datagram received with wrong protocol family" |
d05cc330 |
317 | " %u (expected %u)",udpaddr.sin_family,AF_INET); |
dfdbb32c |
318 | continue; |
319 | } |
5c596e4d |
320 | if (ntohs(udpaddr.sin_port) != DNS_PORT) { |
ae41e040 |
321 | adns__diag(ads,-1,0,"datagram received from wrong port %u (expected %u)", |
5c596e4d |
322 | ntohs(udpaddr.sin_port),DNS_PORT); |
dfdbb32c |
323 | continue; |
324 | } |
325 | for (serv= 0; |
326 | serv < ads->nservers && |
327 | ads->servers[serv].addr.s_addr != udpaddr.sin_addr.s_addr; |
328 | serv++); |
329 | if (serv >= ads->nservers) { |
ae41e040 |
330 | adns__warn(ads,-1,0,"datagram received from unknown nameserver %s", |
d05cc330 |
331 | inet_ntoa(udpaddr.sin_addr)); |
dfdbb32c |
332 | continue; |
333 | } |
c84b7355 |
334 | adns__procdgram(ads,udpbuf,r,serv,0,*now); |
6f17710a |
335 | } |
dfdbb32c |
336 | } |
1389dc72 |
337 | r= 0; |
338 | xit: |
2ac463bf |
339 | adns__consistency(ads,0,cc_entex); |
1389dc72 |
340 | return r; |
6f17710a |
341 | } |
6f17710a |
342 | |
74c94831 |
343 | int adns_processwriteable(adns_state ads, int fd, const struct timeval *now) { |
344 | int r; |
345 | |
2ac463bf |
346 | adns__consistency(ads,0,cc_entex); |
1389dc72 |
347 | |
74c94831 |
348 | switch (ads->tcpstate) { |
349 | case server_disconnected: |
350 | break; |
351 | case server_connecting: |
352 | if (fd != ads->tcpsocket) break; |
353 | assert(ads->tcprecv.used==0); |
ab898cf4 |
354 | assert(ads->tcprecv_skip==0); |
74c94831 |
355 | for (;;) { |
1389dc72 |
356 | if (!adns__vbuf_ensure(&ads->tcprecv,1)) { r= ENOMEM; goto xit; } |
74c94831 |
357 | r= read(ads->tcpsocket,&ads->tcprecv.buf,1); |
358 | if (r==0 || (r<0 && (errno==EAGAIN || errno==EWOULDBLOCK))) { |
359 | tcp_connected(ads,*now); |
1389dc72 |
360 | r= 0; goto xit; |
74c94831 |
361 | } |
362 | if (r>0) { |
363 | adns__tcp_broken(ads,"connect/read","sent data before first request"); |
1389dc72 |
364 | r= 0; goto xit; |
74c94831 |
365 | } |
366 | if (errno==EINTR) continue; |
1389dc72 |
367 | if (errno_resources(errno)) { r= errno; goto xit; } |
74c94831 |
368 | adns__tcp_broken(ads,"connect/read",strerror(errno)); |
1389dc72 |
369 | r= 0; goto xit; |
74c94831 |
370 | } /* not reached */ |
371 | case server_ok: |
372 | if (!(ads->tcpsend.used && fd == ads->tcpsocket)) break; |
373 | for (;;) { |
374 | adns__sigpipe_protect(ads); |
375 | r= write(ads->tcpsocket,ads->tcpsend.buf,ads->tcpsend.used); |
376 | adns__sigpipe_unprotect(ads); |
377 | if (r<0) { |
378 | if (errno==EINTR) continue; |
1389dc72 |
379 | if (errno==EAGAIN || errno==EWOULDBLOCK) { r= 0; goto xit; } |
380 | if (errno_resources(errno)) { r= errno; goto xit; } |
74c94831 |
381 | adns__tcp_broken(ads,"write",strerror(errno)); |
1389dc72 |
382 | r= 0; goto xit; |
74c94831 |
383 | } else if (r>0) { |
384 | ads->tcpsend.used -= r; |
385 | memmove(ads->tcpsend.buf,ads->tcpsend.buf+r,ads->tcpsend.used); |
386 | } |
387 | } /* not reached */ |
388 | default: |
389 | abort(); |
390 | } |
1389dc72 |
391 | r= 0; |
392 | xit: |
2ac463bf |
393 | adns__consistency(ads,0,cc_entex); |
1389dc72 |
394 | return r; |
74c94831 |
395 | } |
396 | |
397 | int adns_processexceptional(adns_state ads, int fd, const struct timeval *now) { |
2ac463bf |
398 | adns__consistency(ads,0,cc_entex); |
74c94831 |
399 | switch (ads->tcpstate) { |
400 | case server_disconnected: |
401 | break; |
402 | case server_connecting: |
403 | case server_ok: |
404 | if (fd != ads->tcpsocket) break; |
405 | adns__tcp_broken(ads,"poll/select","exceptional condition detected"); |
1389dc72 |
406 | break; |
74c94831 |
407 | default: |
408 | abort(); |
409 | } |
2ac463bf |
410 | adns__consistency(ads,0,cc_entex); |
74c94831 |
411 | return 0; |
412 | } |
413 | |
414 | static void fd_event(adns_state ads, int fd, |
415 | int revent, int pollflag, |
416 | int maxfd, const fd_set *fds, |
417 | int (*func)(adns_state, int fd, const struct timeval *now), |
418 | struct timeval now, int *r_r) { |
6f17710a |
419 | int r; |
74c94831 |
420 | |
421 | if (!(revent & pollflag)) return; |
422 | if (fds && !(fd<maxfd && FD_ISSET(fd,fds))) return; |
423 | r= func(ads,fd,&now); |
424 | if (r) { |
425 | if (r_r) { |
426 | *r_r= r; |
427 | } else { |
428 | adns__diag(ads,-1,0,"process fd failed after select: %s",strerror(errno)); |
429 | adns_globalsystemfailure(ads); |
430 | } |
431 | } |
432 | } |
433 | |
434 | void adns__fdevents(adns_state ads, |
435 | const struct pollfd *pollfds, int npollfds, |
436 | int maxfd, const fd_set *readfds, |
437 | const fd_set *writefds, const fd_set *exceptfds, |
438 | struct timeval now, int *r_r) { |
439 | int i, fd, revents; |
440 | |
441 | for (i=0; i<npollfds; i++) { |
442 | fd= pollfds[i].fd; |
443 | if (fd >= maxfd) maxfd= fd+1; |
444 | revents= pollfds[i].revents; |
445 | fd_event(ads,fd, revents,POLLIN, maxfd,readfds, adns_processreadable,now,r_r); |
446 | fd_event(ads,fd, revents,POLLOUT, maxfd,writefds, adns_processwriteable,now,r_r); |
447 | fd_event(ads,fd, revents,POLLPRI, maxfd,exceptfds, adns_processexceptional,now,r_r); |
448 | } |
449 | } |
dfdbb32c |
450 | |
74c94831 |
451 | /* Wrappers for select(2). */ |
452 | |
453 | void adns_beforeselect(adns_state ads, int *maxfd_io, fd_set *readfds_io, |
454 | fd_set *writefds_io, fd_set *exceptfds_io, |
455 | struct timeval **tv_mod, struct timeval *tv_tobuf, |
456 | const struct timeval *now) { |
457 | struct timeval tv_nowbuf; |
458 | struct pollfd pollfds[MAX_POLLFDS]; |
459 | int i, fd, maxfd, npollfds; |
460 | |
2ac463bf |
461 | adns__consistency(ads,0,cc_entex); |
1389dc72 |
462 | |
74c94831 |
463 | if (tv_mod && (!*tv_mod || (*tv_mod)->tv_sec || (*tv_mod)->tv_usec)) { |
464 | /* The caller is planning to sleep. */ |
465 | adns__must_gettimeofday(ads,&now,&tv_nowbuf); |
1389dc72 |
466 | if (!now) goto xit; |
74c94831 |
467 | adns__timeouts(ads, 1, tv_mod,tv_tobuf, *now); |
468 | } |
469 | |
470 | npollfds= adns__pollfds(ads,pollfds); |
471 | maxfd= *maxfd_io; |
472 | for (i=0; i<npollfds; i++) { |
473 | fd= pollfds[i].fd; |
474 | if (fd >= maxfd) maxfd= fd+1; |
475 | if (pollfds[i].events & POLLIN) FD_SET(fd,readfds_io); |
476 | if (pollfds[i].events & POLLOUT) FD_SET(fd,writefds_io); |
477 | if (pollfds[i].events & POLLPRI) FD_SET(fd,exceptfds_io); |
478 | } |
479 | *maxfd_io= maxfd; |
1389dc72 |
480 | |
481 | xit: |
2ac463bf |
482 | adns__consistency(ads,0,cc_entex); |
74c94831 |
483 | } |
484 | |
485 | void adns_afterselect(adns_state ads, int maxfd, const fd_set *readfds, |
486 | const fd_set *writefds, const fd_set *exceptfds, |
487 | const struct timeval *now) { |
4f973eb5 |
488 | struct timeval tv_buf; |
74c94831 |
489 | struct pollfd pollfds[MAX_POLLFDS]; |
4f973eb5 |
490 | int npollfds, i; |
74c94831 |
491 | |
2ac463bf |
492 | adns__consistency(ads,0,cc_entex); |
4f973eb5 |
493 | adns__must_gettimeofday(ads,&now,&tv_buf); |
1389dc72 |
494 | if (!now) goto xit; |
74c94831 |
495 | adns_processtimeouts(ads,now); |
496 | |
497 | npollfds= adns__pollfds(ads,pollfds); |
4f973eb5 |
498 | for (i=0; i<npollfds; i++) pollfds[i].revents= POLLIN|POLLOUT|POLLPRI; |
74c94831 |
499 | adns__fdevents(ads, |
500 | pollfds,npollfds, |
501 | maxfd,readfds,writefds,exceptfds, |
502 | *now, 0); |
1389dc72 |
503 | xit: |
2ac463bf |
504 | adns__consistency(ads,0,cc_entex); |
74c94831 |
505 | } |
506 | |
507 | /* General helpful functions. */ |
508 | |
509 | void adns_globalsystemfailure(adns_state ads) { |
2ac463bf |
510 | adns__consistency(ads,0,cc_entex); |
1389dc72 |
511 | |
74c94831 |
512 | while (ads->timew.head) { |
513 | adns__query_fail(ads->timew.head, adns_s_systemfail); |
514 | } |
515 | |
516 | switch (ads->tcpstate) { |
517 | case server_connecting: |
518 | case server_ok: |
519 | adns__tcp_closenext(ads); |
520 | break; |
521 | case server_disconnected: |
522 | break; |
523 | default: |
524 | abort(); |
525 | } |
2ac463bf |
526 | adns__consistency(ads,0,cc_entex); |
6f17710a |
527 | } |
528 | |
74c94831 |
529 | int adns_processany(adns_state ads) { |
634186ec |
530 | int r, i; |
74c94831 |
531 | struct timeval now; |
532 | struct pollfd pollfds[MAX_POLLFDS]; |
533 | int npollfds; |
534 | |
2ac463bf |
535 | adns__consistency(ads,0,cc_entex); |
1389dc72 |
536 | |
74c94831 |
537 | r= gettimeofday(&now,0); |
538 | if (!r) adns_processtimeouts(ads,&now); |
539 | |
82ab0d30 |
540 | /* We just use adns__fdevents to loop over the fd's trying them. |
541 | * This seems more sensible than calling select, since we're most |
542 | * likely just to want to do a read on one or two fds anyway. |
543 | */ |
74c94831 |
544 | npollfds= adns__pollfds(ads,pollfds); |
634186ec |
545 | for (i=0; i<npollfds; i++) pollfds[i].revents= pollfds[i].events; |
74c94831 |
546 | adns__fdevents(ads, |
547 | pollfds,npollfds, |
548 | 0,0,0,0, |
549 | now,&r); |
1389dc72 |
550 | |
2ac463bf |
551 | adns__consistency(ads,0,cc_entex); |
d16697d9 |
552 | return 0; |
74c94831 |
553 | } |
96e79df5 |
554 | |
d05cc330 |
555 | void adns__autosys(adns_state ads, struct timeval now) { |
96e79df5 |
556 | if (ads->iflags & adns_if_noautosys) return; |
74c94831 |
557 | adns_processany(ads); |
96e79df5 |
558 | } |
559 | |
ef20fccf |
560 | int adns__internal_check(adns_state ads, |
561 | adns_query *query_io, |
562 | adns_answer **answer, |
563 | void **context_r) { |
6f17710a |
564 | adns_query qu; |
565 | |
566 | qu= *query_io; |
567 | if (!qu) { |
c6f9dc7b |
568 | if (!ads->output.head) return EAGAIN; |
6f17710a |
569 | qu= ads->output.head; |
570 | } else { |
c6f9dc7b |
571 | if (qu->id>=0) return EAGAIN; |
6f17710a |
572 | } |
573 | LIST_UNLINK(ads->output,qu); |
965c9782 |
574 | *answer= qu->answer; |
cd1bde2f |
575 | if (context_r) *context_r= qu->ctx.ext; |
8f2aa812 |
576 | *query_io= qu; |
6f17710a |
577 | free(qu); |
578 | return 0; |
579 | } |
580 | |
581 | int adns_wait(adns_state ads, |
582 | adns_query *query_io, |
583 | adns_answer **answer_r, |
584 | void **context_r) { |
74c94831 |
585 | int r, maxfd, rsel; |
6f17710a |
586 | fd_set readfds, writefds, exceptfds; |
587 | struct timeval tvbuf, *tvp; |
588 | |
2ac463bf |
589 | adns__consistency(ads,*query_io,cc_entex); |
6f17710a |
590 | for (;;) { |
ef20fccf |
591 | r= adns__internal_check(ads,query_io,answer_r,context_r); |
c6f9dc7b |
592 | if (r != EAGAIN) break; |
6f17710a |
593 | maxfd= 0; tvp= 0; |
dfdbb32c |
594 | FD_ZERO(&readfds); FD_ZERO(&writefds); FD_ZERO(&exceptfds); |
74c94831 |
595 | adns_beforeselect(ads,&maxfd,&readfds,&writefds,&exceptfds,&tvp,&tvbuf,0); |
6f17710a |
596 | rsel= select(maxfd,&readfds,&writefds,&exceptfds,tvp); |
f318f883 |
597 | if (rsel==-1) { |
74c94831 |
598 | if (errno == EINTR) { |
1389dc72 |
599 | if (ads->iflags & adns_if_eintr) { r= EINTR; break; } |
74c94831 |
600 | } else { |
601 | adns__diag(ads,-1,0,"select failed in wait: %s",strerror(errno)); |
602 | adns_globalsystemfailure(ads); |
603 | } |
604 | } else { |
605 | assert(rsel >= 0); |
606 | adns_afterselect(ads,maxfd,&readfds,&writefds,&exceptfds,0); |
f318f883 |
607 | } |
6f17710a |
608 | } |
2ac463bf |
609 | adns__consistency(ads,0,cc_entex); |
1389dc72 |
610 | return r; |
6f17710a |
611 | } |
612 | |
613 | int adns_check(adns_state ads, |
614 | adns_query *query_io, |
615 | adns_answer **answer_r, |
616 | void **context_r) { |
d05cc330 |
617 | struct timeval now; |
618 | int r; |
619 | |
2ac463bf |
620 | adns__consistency(ads,*query_io,cc_entex); |
74c94831 |
621 | r= gettimeofday(&now,0); |
622 | if (!r) adns__autosys(ads,now); |
1389dc72 |
623 | |
ef20fccf |
624 | r= adns__internal_check(ads,query_io,answer_r,context_r); |
2ac463bf |
625 | adns__consistency(ads,0,cc_entex); |
1389dc72 |
626 | return r; |
6f17710a |
627 | } |