| 1 | /**/ |
| 2 | |
| 3 | static void autosys(adns_state ads, struct timeval now) { |
| 4 | if (ads->iflags & adns_if_noautosys) return; |
| 5 | adns_callback(ads,-1,0,0,0); |
| 6 | } |
| 7 | |
| 8 | static int callb_checkfd(int maxfd, const fd_set *fds, int fd) { |
| 9 | return maxfd<0 || !fds ? 1 : |
| 10 | fd<maxfd && FD_ISSET(fd,fds); |
| 11 | } |
| 12 | |
| 13 | int adns_callback(adns_state ads, int maxfd, |
| 14 | const fd_set *readfds, const fd_set *writefds, |
| 15 | const fd_set *exceptfds) { |
| 16 | int skip, dgramlen, count; |
| 17 | enum adns__tcpstate oldtcpstate; |
| 18 | |
| 19 | count= 0; |
| 20 | oldtcpstate= ads->tcpstate; |
| 21 | |
| 22 | if (ads->tcpstate == server_connecting) { |
| 23 | if (callb_checkfd(maxfd,writefds,ads->tcpsocket)) { |
| 24 | count++; |
| 25 | assert(ads->tcprecv.used==0); |
| 26 | vbuf_ensure(&ads->tcprecv,1); |
| 27 | if (ads->tcprecv.buf) { |
| 28 | r= read(ads->tcpsocket,&ads->tcprecv.buf,1); |
| 29 | if (r==0 || (r<0 && (errno==EAGAIN || errno==EWOULDBLOCK))) { |
| 30 | diag("nameserver %s TCP connection made", |
| 31 | inet_ntoa(ads->servers[ads->tcpserver].addr)); |
| 32 | ads->tcpstate= server_connected; |
| 33 | } else if (r>0) { |
| 34 | tcpserver_broken(ads,"connect/read","sent data before first request"); |
| 35 | } else if (errno!=EINTR) { |
| 36 | tcpserver_broken(ads,"connect",strerror(errno)); |
| 37 | } |
| 38 | } |
| 39 | } |
| 40 | } |
| 41 | if (ads->tcpstate == server_connected) { |
| 42 | if (oldtcpstate == server_connected) |
| 43 | count+= callb_checkfd(maxfd,readfds,ads->tcpsocket) + |
| 44 | callb_checkfd(maxfd,exceptfds,ads->tcpsocket) + |
| 45 | (ads->tcpsend.used && callb_checkfd(maxfd,writefds,ads->tcpsocket)); |
| 46 | if (oldtcpstate != server_connected || callb_checkfd(maxfd,readfds,ads->tcpsocket)) { |
| 47 | skip= 0; |
| 48 | for (;;) { |
| 49 | if (ads->tcprecv.used<skip+2) { |
| 50 | want= 2; |
| 51 | } else { |
| 52 | dgramlen= (ads->tcprecv.buf[skip]<<8) | ads->tcprecv.buf[skip+1]; |
| 53 | if (ads->tcprecv.used<skip+2+dgramlen) { |
| 54 | want= 2+dgramlen; |
| 55 | } else { |
| 56 | procdgram(ads,ads->tcprecv.buf+skip+2,dgramlen,-1); |
| 57 | skip+= 2+dgramlen; continue; |
| 58 | } |
| 59 | } |
| 60 | Ads->tcprecv.used -= skip; |
| 61 | memmove(ads->tcprecv.buf,ads->tcprecv.buf+skip,ads->tcprecv.used); |
| 62 | vbuf_ensure(&ads->tcprecv,want); |
| 63 | if (ads->tcprecv.used >= ads->tcprecv.avail) break; |
| 64 | r= read(ads->tcpsocket, |
| 65 | ads->tcprecv.buf+ads->tcprecv.used, |
| 66 | ads->tcprecv.avail-ads->tcprecv.used); |
| 67 | if (r>0) { |
| 68 | ads->tcprecv.used+= r; |
| 69 | } else { |
| 70 | if (r<0) { |
| 71 | if (errno==EAGAIN || errno==EWOULDBLOCK || errno==ENOMEM) break; |
| 72 | if (errno==EINTR) continue; |
| 73 | } |
| 74 | tcpserver_broken(ads->tcpserver,"read",r?strerror(errno):"closed"); |
| 75 | break; |
| 76 | } |
| 77 | } |
| 78 | } else if (callb_checkfd(maxfd,exceptfds,ads->tcpsocket)) { |
| 79 | tcpserver_broken(ads->tcpserver,"select","exceptional condition detected"); |
| 80 | } else if (ads->tcpsend.used && callb_checkfd(maxfd,writefds,ads->tcpsocket)) { |
| 81 | r= write(ads->tcpsocket,ads->tcpsend.buf,ads->tcpsend.used); |
| 82 | if (r<0) { |
| 83 | if (errno!=EAGAIN && errno!=EWOULDBLOCK && errno!=ENOMEM && errno!=EINTR) { |
| 84 | tcpserver_broken(ads->tcpserver,"write",strerror(errno)); |
| 85 | } |
| 86 | } else if (r>0) { |
| 87 | ads->tcpsend.used -= r; |
| 88 | memmove(ads->tcpsend.buf,ads->tcpsend.buf+r,ads->tcpsend.used); |
| 89 | } |
| 90 | } |
| 91 | } |
| 92 | |
| 93 | if ( |
| 94 | break; |
| 95 | |
| 96 | |
| 97 | } |
| 98 | |
| 99 | tcpserver_broken( |
| 100 | |
| 101 | if (ads- |
| 102 | used= 0; |
| 103 | for (;;) { |
| 104 | vbuf_ensure(&ads->tcprecv,2); |
| 105 | vbuf_ensure(&ads->tcprecv, |
| 106 | if (ads->tcprecv.avail<2) break; |
| 107 | if (ads->tcprecv.used |
| 108 | |
| 109 | if (ads->tcprecv.used<2 && ads->tcprecv.avail |
| 110 | if (ads->tcprecv.used<2 && ads->tcprecv.avail |
| 111 | r= read(ads->tcpsocket, |
| 112 | if (adns->tcprecv.used<2) { |
| 113 | if ( |
| 114 | |
| 115 | if (ads->tcpstate != server_disc) { |
| 116 | |
| 117 | |
| 118 | } |
| 119 | if (maxfd<0 || !readfds || (FD_ISSET |
| 120 | ads-> |
| 121 | |
| 122 | abort(); /* FIXME */ |
| 123 | } |
| 124 | diag("nameserver #%d (%s) TCP connection died: %s", |
| 125 | inet_ntoa(ads->servers[tcpserver].addr), |
| 126 | |
| 127 | static void inter_maxto(struct timeval **tv_io, struct timeval *tvbuf, |
| 128 | struct timeval maxto) { |
| 129 | struct timeval rbuf; |
| 130 | |
| 131 | rbuf= *tv_io; |
| 132 | if (!rbuf) { *tvbuf= maxto; *tv_io= tvbuf; return; } |
| 133 | if (timercmp(rbuf,&maxto,>)) *rbuf= maxto; |
| 134 | } |
| 135 | |
| 136 | static void inter_maxtoabs(struct timeval **tv_io, struct timeval *tvbuf, |
| 137 | struct timeval now, struct timeval maxtime) { |
| 138 | ldiv_t dr; |
| 139 | |
| 140 | maxtime.tv_sec -= (now.tv_sec-1); |
| 141 | maxtime.tv_usec += (1000-now.tv_usec); |
| 142 | dr= ldiv(maxtime.tv_usec,1000); |
| 143 | maxtime.tv_sec += dr.quot; |
| 144 | maxtime.tv_usec -= dr.rem; |
| 145 | inter_maxto(tv_io,tvbuf,maxtime); |
| 146 | } |
| 147 | |
| 148 | static void localresourcerr(struct timeval **tv_io, struct timeval *tvbuf, |
| 149 | const char *syscall) { |
| 150 | struct timeval tvto_lr; |
| 151 | |
| 152 | diag(ads,"local system resources scarce (during %s): %s",syscall,strerror(errno)); |
| 153 | timerclear(&tvto_lr); timevaladd(&tvto_lr,LOCALRESOURCEMS); |
| 154 | inter_maxto(tv_io, tvbuf, tvto_lr); |
| 155 | return; |
| 156 | } |
| 157 | |
| 158 | static void inter_addfd(int *maxfd, fd_set *fds, int fd) { |
| 159 | if (fd>=*maxfd) *maxfd= fd+1; |
| 160 | FD_SET(fd,fds); |
| 161 | } |
| 162 | |
| 163 | void adns_interest(adns_state ads, int *maxfd, |
| 164 | fd_set *readfds, fd_set *writefds, fd_set *exceptfds, |
| 165 | struct timeval **tv_io, struct timeval *tvbuf) { |
| 166 | struct timeval now; |
| 167 | adns_query qu; |
| 168 | int r; |
| 169 | |
| 170 | r= gettimeofday(&now,0); |
| 171 | if (r) { localresourcerr(tv_io,tvbuf,"gettimeofday"); return; } |
| 172 | |
| 173 | for (qu= ads->timew; qu; qu= nqu) { |
| 174 | nqu= qu->next; |
| 175 | if (timercmp(&now,qu->timeout,>)) { |
| 176 | DLIST_UNLINK(ads->timew,qu); |
| 177 | if (qu->nextudpserver == -1) { |
| 178 | query_fail(ads,qu,adns_s_notresponding); |
| 179 | } else { |
| 180 | DLIST_LINKTAIL(ads->tosend,qu); |
| 181 | } |
| 182 | } else { |
| 183 | inter_maxtoabs(tv_io,tvbuf,now,qu->timeout); |
| 184 | } |
| 185 | } |
| 186 | |
| 187 | for (qu= ads->tosend; qu; qu= nqu) { |
| 188 | nqu= qu->next; |
| 189 | quproc_tosend(ads,qu,now); |
| 190 | } |
| 191 | |
| 192 | inter_addfd(maxfd,readfds,ads->udpsocket); |
| 193 | switch (ads->tcpstate) { |
| 194 | case server_disc: |
| 195 | break; |
| 196 | case server_connecting: |
| 197 | inter_addfd(maxfd,writefds,ads->tcpsocket); |
| 198 | break; |
| 199 | case server_connected: |
| 200 | inter_addfd(maxfd,readfds,ads->tcpsocket); |
| 201 | inter_addfd(maxfd,exceptfds,ads->tcpsocket); |
| 202 | if (ads->opbufused) inter_addfd(maxfd,writefds,ads->tcpsocket); |
| 203 | default: |
| 204 | abort(); |
| 205 | } |
| 206 | |
| 207 | } |
| 208 | |
| 209 | static int internal_check(adns_state ads, |
| 210 | adns_query *query_io, |
| 211 | adns_answer **answer, |
| 212 | void **context_r) { |
| 213 | adns_query qu; |
| 214 | |
| 215 | qu= *query_io; |
| 216 | if (!qu) { |
| 217 | if (!ads->output.head) return EWOULDBLOCK; |
| 218 | qu= ads->output.head; |
| 219 | } else { |
| 220 | if (qu->id>=0) return EWOULDBLOCK; |
| 221 | } |
| 222 | LIST_UNLINK(ads->output,qu); |
| 223 | *answer= qu->answer; |
| 224 | if (context_r) *context_r= qu->context; |
| 225 | free(qu); |
| 226 | return 0; |
| 227 | } |
| 228 | |
| 229 | int adns_wait(adns_state ads, |
| 230 | adns_query *query_io, |
| 231 | adns_answer **answer_r, |
| 232 | void **context_r) { |
| 233 | int r, maxfd, rsel, rcb; |
| 234 | fd_set readfds, writefds, exceptfds; |
| 235 | struct timeval tvbuf, *tvp; |
| 236 | |
| 237 | for (;;) { |
| 238 | r= internal_check(ads,query_io,answer_r,context_r); |
| 239 | if (r && r != EWOULDBLOCK) return r; |
| 240 | FD_ZERO(&readfds); FD_ZERO(&writefds); FD_ZERO(&exceptfds); |
| 241 | maxfd= 0; tvp= 0; |
| 242 | adns_interest(ads,&maxfd,&readfds,&writefds,&exceptfds,&tvp,&tvbuf); |
| 243 | rsel= select(maxfd,&readfds,&writefds,&exceptfds,tvp); |
| 244 | if (rsel==-1) return r; |
| 245 | rcb= adns_callback(ads,maxfd,&readfds,&writefds,&exceptfds); |
| 246 | assert(rcb==rsel); |
| 247 | } |
| 248 | } |
| 249 | |
| 250 | int adns_check(adns_state ads, |
| 251 | adns_query *query_io, |
| 252 | adns_answer **answer_r, |
| 253 | void **context_r) { |
| 254 | autosys(ads); |
| 255 | return internal_check(ads,query_io,answer_r,context_r); |
| 256 | } |