1 /*
2 * poll.c
3 * - wrappers for poll(2)
4 */
5 /*
6 * This file is
7 * Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk>
8 *
9 * It is part of adns, which is
10 * Copyright (C) 1997-2000 Ian Jackson <ian@davenant.greenend.org.uk>
11 * Copyright (C) 1999-2000 Tony Finch <dot@dotat.at>
12 *
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2, or (at your option)
16 * any later version.
17 *
18 * This program is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 * GNU General Public License for more details.
22 *
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software Foundation,
25 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
26 */
27
28 #include <limits.h>
29 #include <string.h>
30
31 #include "internal.h"
32
33 #ifdef HAVE_POLL
34
adns_beforepoll(adns_state ads,struct pollfd * fds,int * nfds_io,int * timeout_io,const struct timeval * now)35 int adns_beforepoll(adns_state ads, struct pollfd *fds, int *nfds_io, int *timeout_io,
36 const struct timeval *now) {
37 struct timeval tv_nowbuf, tv_tobuf, *tv_to;
38 int space, found, timeout_ms, r;
39 struct pollfd fds_tmp[MAX_POLLFDS];
40
41 adns__consistency(ads,0,cc_entex);
42
43 if (timeout_io) {
44 adns__must_gettimeofday(ads,&now,&tv_nowbuf);
45 if (!now) { *nfds_io= 0; r= 0; goto xit; }
46
47 timeout_ms= *timeout_io;
48 if (timeout_ms == -1) {
49 tv_to= 0;
50 } else {
51 tv_tobuf.tv_sec= timeout_ms / 1000;
52 tv_tobuf.tv_usec= (timeout_ms % 1000)*1000;
53 tv_to= &tv_tobuf;
54 }
55
56 adns__timeouts(ads, 0, &tv_to,&tv_tobuf, *now);
57
58 if (tv_to) {
59 assert(tv_to == &tv_tobuf);
60 timeout_ms= (tv_tobuf.tv_usec+999)/1000;
61 assert(tv_tobuf.tv_sec < (INT_MAX-timeout_ms)/1000);
62 timeout_ms += tv_tobuf.tv_sec*1000;
63 } else {
64 timeout_ms= -1;
65 }
66 *timeout_io= timeout_ms;
67 }
68
69 space= *nfds_io;
70 if (space >= MAX_POLLFDS) {
71 found= adns__pollfds(ads,fds);
72 *nfds_io= found;
73 } else {
74 found= adns__pollfds(ads,fds_tmp);
75 *nfds_io= found;
76 if (space < found) { r= ERANGE; goto xit; }
77 memcpy(fds,fds_tmp,sizeof(struct pollfd)*found);
78 }
79 r= 0;
80 xit:
81 adns__consistency(ads,0,cc_entex);
82 return r;
83 }
84
adns_afterpoll(adns_state ads,const struct pollfd * fds,int nfds,const struct timeval * now)85 void adns_afterpoll(adns_state ads, const struct pollfd *fds, int nfds,
86 const struct timeval *now) {
87 struct timeval tv_buf;
88
89 adns__consistency(ads,0,cc_entex);
90 adns__must_gettimeofday(ads,&now,&tv_buf);
91 if (now) {
92 adns__timeouts(ads, 1, 0,0, *now);
93 adns__fdevents(ads, fds,nfds, 0,0,0,0, *now,0);
94 }
95 adns__consistency(ads,0,cc_entex);
96 }
97
adns_wait_poll(adns_state ads,adns_query * query_io,adns_answer ** answer_r,void ** context_r)98 int adns_wait_poll(adns_state ads,
99 adns_query *query_io,
100 adns_answer **answer_r,
101 void **context_r) {
102 int r, nfds, to;
103 struct pollfd fds[MAX_POLLFDS];
104
105 adns__consistency(ads,0,cc_entex);
106
107 for (;;) {
108 r= adns__internal_check(ads,query_io,answer_r,context_r);
109 if (r != EAGAIN) goto xit;
110 nfds= MAX_POLLFDS; to= -1;
111 adns_beforepoll(ads,fds,&nfds,&to,0);
112 r= poll(fds,nfds,to);
113 if (r == -1) {
114 if (errno == EINTR) {
115 if (ads->iflags & adns_if_eintr) { r= EINTR; goto xit; }
116 } else {
117 adns__diag(ads,-1,0,"poll failed in wait: %s",strerror(errno));
118 adns_globalsystemfailure(ads);
119 }
120 } else {
121 assert(r >= 0);
122 adns_afterpoll(ads,fds,nfds,0);
123 }
124 }
125
126 xit:
127 adns__consistency(ads,0,cc_entex);
128 return r;
129 }
130
131 #endif
132