X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;ds=sidebyside;f=src%2Fevent.c;h=3621bc8b2ece48d2b03dd16dad955dbe2a217cce;hb=26e1c3d691b52d21a8bb52d9bf3f8e2b42ae6cfa;hp=b2da291e0856ee77669393638b8dd1c409ca6573;hpb=226c5eef1caec08ee33276de158e263c0593c0d0;p=adns.git diff --git a/src/event.c b/src/event.c index b2da291..3621bc8 100644 --- a/src/event.c +++ b/src/event.c @@ -5,16 +5,15 @@ * - user-visible check/wait and event-loop-related functions */ /* - * This file is - * Copyright (C) 1997-1999 Ian Jackson - * - * It is part of adns, which is - * Copyright (C) 1997-1999 Ian Jackson - * Copyright (C) 1999 Tony Finch + * This file is part of adns, which is + * Copyright (C) 1997-2000,2003,2006,2014 Ian Jackson + * Copyright (C) 1999-2000,2003,2006 Tony Finch + * Copyright (C) 1991 Massachusetts Institute of Technology + * (See the file INSTALL for full details.) * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2, or (at your option) + * the Free Software Foundation; either version 3, or (at your option) * any later version. * * This program is distributed in the hope that it will be useful, @@ -23,8 +22,7 @@ * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software Foundation, - * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * along with this program; if not, write to the Free Software Foundation. */ #include @@ -39,40 +37,33 @@ #include #include "internal.h" +#include "tvarith.h" /* TCP connection management. */ -void adns__tcp_closenext(adns_state ads) { - int serv; - - serv= ads->tcpserver; +static void tcp_close(adns_state ads) { close(ads->tcpsocket); ads->tcpsocket= -1; - ads->tcpstate= server_disconnected; ads->tcprecv.used= ads->tcprecv_skip= ads->tcpsend.used= 0; - ads->tcpserver= (serv+1)%ads->nservers; } void adns__tcp_broken(adns_state ads, const char *what, const char *why) { int serv; - adns_query qu, nqu; + adns_query qu; assert(ads->tcpstate == server_connecting || ads->tcpstate == server_ok); serv= ads->tcpserver; - adns__warn(ads,serv,0,"TCP connection lost: %s: %s",what,why); - adns__tcp_closenext(ads); - - for (qu= ads->timew.head; qu; qu= nqu) { - nqu= qu->next; - if (qu->state == query_tosend) continue; - assert(qu->state == query_tcpwait || qu->state == query_tcpsent); - qu->state= query_tcpwait; - qu->tcpfailed |= (1<tcpfailed == (1<nservers)-1) { - LIST_UNLINK(ads->timew,qu); - adns__query_fail(qu,adns_s_allservfail); - } + if (what) adns__warn(ads,serv,0,"TCP connection failed: %s: %s",what,why); + + if (ads->tcpstate == server_connecting) { + /* Counts as a retry for all the queries waiting for TCP. */ + for (qu= ads->tcpw.head; qu; qu= qu->next) + qu->retries++; } + + tcp_close(ads); + ads->tcpstate= server_broken; + ads->tcpserver= (serv+1)%ads->nservers; } static void tcp_connected(adns_state ads, struct timeval now) { @@ -80,49 +71,78 @@ static void tcp_connected(adns_state ads, struct timeval now) { adns__debug(ads,ads->tcpserver,0,"TCP connected"); ads->tcpstate= server_ok; - for (qu= ads->timew.head; qu; qu= nqu) { + for (qu= ads->tcpw.head; qu && ads->tcpstate == server_ok; qu= nqu) { nqu= qu->next; - if (qu->state == query_tosend) continue; - assert (qu->state == query_tcpwait); - adns__query_tcp(qu,now); + assert(qu->state == query_tcpw); + adns__querysend_tcp(qu,now); + } +} + +static void tcp_broken_events(adns_state ads) { + adns_query qu, nqu; + + assert(ads->tcpstate == server_broken); + for (qu= ads->tcpw.head; qu; qu= nqu) { + nqu= qu->next; + assert(qu->state == query_tcpw); + if (qu->retries > ads->nservers) { + LIST_UNLINK(ads->tcpw,qu); + adns__query_fail(qu,adns_s_allservfail); + } } + ads->tcpstate= server_disconnected; } void adns__tcp_tryconnect(adns_state ads, struct timeval now) { int r, fd, tries; - struct sockaddr_in addr; + adns_rr_addr *addr; struct protoent *proto; for (tries=0; triesnservers; tries++) { - if (ads->tcpstate == server_connecting || ads->tcpstate == server_ok) return; - assert(ads->tcpstate == server_disconnected); + switch (ads->tcpstate) { + case server_connecting: + case server_ok: + case server_broken: + return; + case server_disconnected: + break; + default: + abort(); + } + assert(!ads->tcpsend.used); assert(!ads->tcprecv.used); assert(!ads->tcprecv_skip); proto= getprotobyname("tcp"); - if (!proto) { adns__diag(ads,-1,0,"unable to find protocol no. for TCP !"); return; } - fd= socket(AF_INET,SOCK_STREAM,proto->p_proto); + if (!proto) { + adns__diag(ads,-1,0,"unable to find protocol no. for TCP !"); + return; + } + addr = &ads->servers[ads->tcpserver]; + fd= socket(addr->addr.sa.sa_family, SOCK_STREAM, proto->p_proto); if (fd<0) { adns__diag(ads,-1,0,"cannot create TCP socket: %s",strerror(errno)); return; } r= adns__setnonblock(ads,fd); if (r) { - adns__diag(ads,-1,0,"cannot make TCP socket nonblocking: %s",strerror(r)); + adns__diag(ads,-1,0,"cannot make TCP socket nonblocking:" + " %s",strerror(r)); close(fd); return; } - memset(&addr,0,sizeof(addr)); - addr.sin_family= AF_INET; - addr.sin_port= htons(DNS_PORT); - addr.sin_addr= ads->servers[ads->tcpserver].addr; - r= connect(fd,(const struct sockaddr*)&addr,sizeof(addr)); + r= connect(fd,&addr->addr.sa,addr->len); ads->tcpsocket= fd; ads->tcpstate= server_connecting; - if (r==0) { tcp_connected(ads,now); continue; } - if (errno == EWOULDBLOCK || errno == EINPROGRESS) return; + if (r==0) { tcp_connected(ads,now); return; } + if (errno == EWOULDBLOCK || errno == EINPROGRESS) { + ads->tcptimeout= now; + timevaladd(&ads->tcptimeout,TCPCONNMS); + return; + } adns__tcp_broken(ads,"connect",strerror(errno)); + tcp_broken_events(ads); } } @@ -141,6 +161,17 @@ void adns__must_gettimeofday(adns_state ads, const struct timeval **now_io, return; } +static void inter_immed(struct timeval **tv_io, struct timeval *tvbuf) { + struct timeval *rbuf; + + if (!tv_io) return; + + rbuf= *tv_io; + if (!rbuf) { *tv_io= rbuf= tvbuf; } + + timerclear(rbuf); +} + static void inter_maxto(struct timeval **tv_io, struct timeval *tvbuf, struct timeval maxto) { struct timeval *rbuf; @@ -158,6 +189,7 @@ static void inter_maxto(struct timeval **tv_io, struct timeval *tvbuf, static void inter_maxtoabs(struct timeval **tv_io, struct timeval *tvbuf, struct timeval now, struct timeval maxtime) { + /* tv_io may be 0 */ ldiv_t dr; /*fprintf(stderr,"inter_maxtoabs now=%ld.%06ld maxtime=%ld.%06ld\n", @@ -172,35 +204,88 @@ static void inter_maxtoabs(struct timeval **tv_io, struct timeval *tvbuf, inter_maxto(tv_io,tvbuf,maxtime); } -void adns__timeouts(adns_state ads, int act, - struct timeval **tv_io, struct timeval *tvbuf, - struct timeval now) { +static void timeouts_queue(adns_state ads, int act, + struct timeval **tv_io, struct timeval *tvbuf, + struct timeval now, struct query_queue *queue) { adns_query qu, nqu; - - for (qu= ads->timew.head; qu; qu= nqu) { + + for (qu= queue->head; qu; qu= nqu) { nqu= qu->next; if (!timercmp(&now,&qu->timeout,>)) { - if (!tv_io) continue; inter_maxtoabs(tv_io,tvbuf,now,qu->timeout); } else { - if (!act) continue; - LIST_UNLINK(ads->timew,qu); + if (!act) { inter_immed(tv_io,tvbuf); return; } + LIST_UNLINK(*queue,qu); if (qu->state != query_tosend) { adns__query_fail(qu,adns_s_timeout); } else { adns__query_send(qu,now); } - nqu= ads->timew.head; + nqu= queue->head; } } -} +} + +static void tcp_events(adns_state ads, int act, + struct timeval **tv_io, struct timeval *tvbuf, + struct timeval now) { + for (;;) { + switch (ads->tcpstate) { + case server_broken: + if (!act) { inter_immed(tv_io,tvbuf); return; } + tcp_broken_events(ads); + case server_disconnected: /* fall through */ + if (!ads->tcpw.head) return; + if (!act) { inter_immed(tv_io,tvbuf); return; } + adns__tcp_tryconnect(ads,now); + break; + case server_ok: + if (ads->tcpw.head) return; + if (!ads->tcptimeout.tv_sec) { + assert(!ads->tcptimeout.tv_usec); + ads->tcptimeout= now; + timevaladd(&ads->tcptimeout,TCPIDLEMS); + } + case server_connecting: /* fall through */ + if (!act || !timercmp(&now,&ads->tcptimeout,>)) { + inter_maxtoabs(tv_io,tvbuf,now,ads->tcptimeout); + return; + } { + /* TCP timeout has happened */ + switch (ads->tcpstate) { + case server_connecting: /* failed to connect */ + adns__tcp_broken(ads,"unable to make connection","timed out"); + break; + case server_ok: /* idle timeout */ + tcp_close(ads); + ads->tcpstate= server_disconnected; + return; + default: + abort(); + } + } + break; + default: + abort(); + } + } + return; +} + +void adns__timeouts(adns_state ads, int act, + struct timeval **tv_io, struct timeval *tvbuf, + struct timeval now) { + timeouts_queue(ads,act,tv_io,tvbuf,now, &ads->udpw); + timeouts_queue(ads,act,tv_io,tvbuf,now, &ads->tcpw); + tcp_events(ads,act,tv_io,tvbuf,now); +} void adns_firsttimeout(adns_state ads, struct timeval **tv_io, struct timeval *tvbuf, struct timeval now) { adns__consistency(ads,0,cc_entex); adns__timeouts(ads, 0, tv_io,tvbuf, now); - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); } void adns_processtimeouts(adns_state ads, const struct timeval *now) { @@ -209,7 +294,7 @@ void adns_processtimeouts(adns_state ads, const struct timeval *now) { adns__consistency(ads,0,cc_entex); adns__must_gettimeofday(ads,&now,&tv_buf); if (now) adns__timeouts(ads, 1, 0,0, *now); - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); } /* fd handling functions. These are the top-level of the real work of @@ -218,44 +303,58 @@ void adns_processtimeouts(adns_state ads, const struct timeval *now) { int adns__pollfds(adns_state ads, struct pollfd pollfds_buf[MAX_POLLFDS]) { /* Returns the number of entries filled in. Always zeroes revents. */ + int nwanted=0; +#define ADD_POLLFD(wantfd, wantevents) do{ \ + pollfds_buf[nwanted].fd= (wantfd); \ + pollfds_buf[nwanted].events= (wantevents); \ + pollfds_buf[nwanted].revents= 0; \ + nwanted++; \ + }while(0) + + int i; - assert(MAX_POLLFDS==2); + assert(MAX_POLLFDS == MAXUDP + 1); - pollfds_buf[0].fd= ads->udpsocket; - pollfds_buf[0].events= POLLIN; - pollfds_buf[0].revents= 0; + for (i=0; inudpsockets; i++) + ADD_POLLFD(ads->udpsockets[i].fd, POLLIN); switch (ads->tcpstate) { case server_disconnected: - return 1; + case server_broken: + break; case server_connecting: - pollfds_buf[1].events= POLLOUT; + ADD_POLLFD(ads->tcpsocket, POLLOUT); break; case server_ok: - pollfds_buf[1].events= ads->tcpsend.used ? POLLIN|POLLOUT|POLLPRI : POLLIN|POLLPRI; + ADD_POLLFD(ads->tcpsocket, + ads->tcpsend.used ? POLLIN|POLLOUT|POLLPRI : POLLIN|POLLPRI); break; default: abort(); } - pollfds_buf[1].fd= ads->tcpsocket; - return 2; + assert(nwanted<=MAX_POLLFDS); +#undef ADD_POLLFD + return nwanted; } int adns_processreadable(adns_state ads, int fd, const struct timeval *now) { - int want, dgramlen, r, udpaddrlen, serv, old_skip; + int want, dgramlen, r, i, udpaddrlen, serv, old_skip; byte udpbuf[DNS_MAXUDP]; - struct sockaddr_in udpaddr; + char addrbuf[ADNS_ADDR2TEXT_BUFLEN]; + struct udpsocket *udp; + adns_sockaddr udpaddr; adns__consistency(ads,0,cc_entex); switch (ads->tcpstate) { case server_disconnected: + case server_broken: case server_connecting: break; case server_ok: if (fd != ads->tcpsocket) break; assert(!ads->tcprecv_skip); - for (;;) { + do { if (ads->tcprecv.used >= ads->tcprecv_skip+2) { dgramlen= ((ads->tcprecv.buf[ads->tcprecv_skip]<<8) | ads->tcprecv.buf[ads->tcprecv_skip+1]); @@ -272,7 +371,8 @@ int adns_processreadable(adns_state ads, int fd, const struct timeval *now) { want= 2; } ads->tcprecv.used -= ads->tcprecv_skip; - memmove(ads->tcprecv.buf,ads->tcprecv.buf+ads->tcprecv_skip,ads->tcprecv.used); + memmove(ads->tcprecv.buf, ads->tcprecv.buf+ads->tcprecv_skip, + ads->tcprecv.used); ads->tcprecv_skip= 0; if (!adns__vbuf_ensure(&ads->tcprecv,want)) { r= ENOMEM; goto xit; } assert(ads->tcprecv.used <= ads->tcprecv.avail); @@ -289,17 +389,18 @@ int adns_processreadable(adns_state ads, int fd, const struct timeval *now) { if (errno_resources(errno)) { r= errno; goto xit; } } adns__tcp_broken(ads,"read",r?strerror(errno):"closed"); - r= 0; goto xit; } - } /* never reached */ + } while (ads->tcpstate == server_ok); + r= 0; goto xit; default: abort(); } - if (fd == ads->udpsocket) { + for (i=0; inudpsockets; i++) { + udp= &ads->udpsockets[i]; + if (fd != udp->fd) continue; for (;;) { udpaddrlen= sizeof(udpaddr); - r= recvfrom(ads->udpsocket,udpbuf,sizeof(udpbuf),0, - (struct sockaddr*)&udpaddr,&udpaddrlen); + r= recvfrom(fd,udpbuf,sizeof(udpbuf),0, &udpaddr.sa,&udpaddrlen); if (r<0) { if (errno == EAGAIN || errno == EWOULDBLOCK) { r= 0; goto xit; } if (errno == EINTR) continue; @@ -307,36 +408,23 @@ int adns_processreadable(adns_state ads, int fd, const struct timeval *now) { adns__warn(ads,-1,0,"datagram receive error: %s",strerror(errno)); r= 0; goto xit; } - if (udpaddrlen != sizeof(udpaddr)) { - adns__diag(ads,-1,0,"datagram received with wrong address length %d" - " (expected %d)", udpaddrlen,sizeof(udpaddr)); - continue; - } - if (udpaddr.sin_family != AF_INET) { - adns__diag(ads,-1,0,"datagram received with wrong protocol family" - " %u (expected %u)",udpaddr.sin_family,AF_INET); - continue; - } - if (ntohs(udpaddr.sin_port) != DNS_PORT) { - adns__diag(ads,-1,0,"datagram received from wrong port %u (expected %u)", - ntohs(udpaddr.sin_port),DNS_PORT); - continue; - } for (serv= 0; serv < ads->nservers && - ads->servers[serv].addr.s_addr != udpaddr.sin_addr.s_addr; + !adns__sockaddrs_equal(&udpaddr.sa, + &ads->servers[serv].addr.sa); serv++); if (serv >= ads->nservers) { adns__warn(ads,-1,0,"datagram received from unknown nameserver %s", - inet_ntoa(udpaddr.sin_addr)); + adns__sockaddr_ntoa(&udpaddr.sa, addrbuf)); continue; } adns__procdgram(ads,udpbuf,r,serv,0,*now); } + break; } r= 0; xit: - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); return r; } @@ -347,6 +435,7 @@ int adns_processwriteable(adns_state ads, int fd, const struct timeval *now) { switch (ads->tcpstate) { case server_disconnected: + case server_broken: break; case server_connecting: if (fd != ads->tcpsocket) break; @@ -369,8 +458,8 @@ int adns_processwriteable(adns_state ads, int fd, const struct timeval *now) { r= 0; goto xit; } /* not reached */ case server_ok: - if (!(ads->tcpsend.used && fd == ads->tcpsocket)) break; - for (;;) { + if (fd != ads->tcpsocket) break; + while (ads->tcpsend.used) { adns__sigpipe_protect(ads); r= write(ads->tcpsocket,ads->tcpsend.buf,ads->tcpsend.used); adns__sigpipe_unprotect(ads); @@ -384,20 +473,24 @@ int adns_processwriteable(adns_state ads, int fd, const struct timeval *now) { ads->tcpsend.used -= r; memmove(ads->tcpsend.buf,ads->tcpsend.buf+r,ads->tcpsend.used); } - } /* not reached */ + } + r= 0; + goto xit; default: abort(); } r= 0; xit: - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); return r; } -int adns_processexceptional(adns_state ads, int fd, const struct timeval *now) { +int adns_processexceptional(adns_state ads, int fd, + const struct timeval *now) { adns__consistency(ads,0,cc_entex); switch (ads->tcpstate) { case server_disconnected: + case server_broken: break; case server_connecting: case server_ok: @@ -407,14 +500,15 @@ int adns_processexceptional(adns_state ads, int fd, const struct timeval *now) { default: abort(); } - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); return 0; } static void fd_event(adns_state ads, int fd, int revent, int pollflag, int maxfd, const fd_set *fds, - int (*func)(adns_state, int fd, const struct timeval *now), + int (*func)(adns_state, int fd, + const struct timeval *now), struct timeval now, int *r_r) { int r; @@ -425,7 +519,8 @@ static void fd_event(adns_state ads, int fd, if (r_r) { *r_r= r; } else { - adns__diag(ads,-1,0,"process fd failed after select: %s",strerror(errno)); + adns__diag(ads,-1,0,"process fd failed after select:" + " %s",strerror(errno)); adns_globalsystemfailure(ads); } } @@ -442,9 +537,12 @@ void adns__fdevents(adns_state ads, fd= pollfds[i].fd; if (fd >= maxfd) maxfd= fd+1; revents= pollfds[i].revents; - fd_event(ads,fd, revents,POLLIN, maxfd,readfds, adns_processreadable,now,r_r); - fd_event(ads,fd, revents,POLLOUT, maxfd,writefds, adns_processwriteable,now,r_r); - fd_event(ads,fd, revents,POLLPRI, maxfd,exceptfds, adns_processexceptional,now,r_r); +#define EV(pollfl,fds,how) \ + fd_event(ads,fd, revents,pollfl, maxfd,fds, adns_process##how,now,r_r) + EV( POLLIN, readfds, readable ); + EV( POLLOUT, writefds, writeable ); + EV( POLLPRI, exceptfds, exceptional ); +#undef EV } } @@ -463,8 +561,8 @@ void adns_beforeselect(adns_state ads, int *maxfd_io, fd_set *readfds_io, if (tv_mod && (!*tv_mod || (*tv_mod)->tv_sec || (*tv_mod)->tv_usec)) { /* The caller is planning to sleep. */ adns__must_gettimeofday(ads,&now,&tv_nowbuf); - if (!now) goto xit; - adns__timeouts(ads, 1, tv_mod,tv_tobuf, *now); + if (!now) { inter_immed(tv_mod,tv_tobuf); goto xit; } + adns__timeouts(ads, 0, tv_mod,tv_tobuf, *now); } npollfds= adns__pollfds(ads,pollfds); @@ -479,7 +577,7 @@ void adns_beforeselect(adns_state ads, int *maxfd_io, fd_set *readfds_io, *maxfd_io= maxfd; xit: - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); } void adns_afterselect(adns_state ads, int maxfd, const fd_set *readfds, @@ -501,7 +599,7 @@ void adns_afterselect(adns_state ads, int maxfd, const fd_set *readfds, maxfd,readfds,writefds,exceptfds, *now, 0); xit: - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); } /* General helpful functions. */ @@ -509,21 +607,21 @@ xit: void adns_globalsystemfailure(adns_state ads) { adns__consistency(ads,0,cc_entex); - while (ads->timew.head) { - adns__query_fail(ads->timew.head, adns_s_systemfail); - } + while (ads->udpw.head) adns__query_fail(ads->udpw.head, adns_s_systemfail); + while (ads->tcpw.head) adns__query_fail(ads->tcpw.head, adns_s_systemfail); switch (ads->tcpstate) { case server_connecting: case server_ok: - adns__tcp_closenext(ads); + adns__tcp_broken(ads,0,0); break; case server_disconnected: + case server_broken: break; default: abort(); } - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); } int adns_processany(adns_state ads) { @@ -542,13 +640,13 @@ int adns_processany(adns_state ads) { * likely just to want to do a read on one or two fds anyway. */ npollfds= adns__pollfds(ads,pollfds); - for (i=0; ioutput.head) return EAGAIN; - qu= ads->output.head; + if (ads->output.head) { + qu= ads->output.head; + } else if (ads->udpw.head || ads->tcpw.head) { + return EAGAIN; + } else { + return ESRCH; + } } else { if (qu->id>=0) return EAGAIN; } @@ -593,6 +696,7 @@ int adns_wait(adns_state ads, maxfd= 0; tvp= 0; FD_ZERO(&readfds); FD_ZERO(&writefds); FD_ZERO(&exceptfds); adns_beforeselect(ads,&maxfd,&readfds,&writefds,&exceptfds,&tvp,&tvbuf,0); + assert(tvp); rsel= select(maxfd,&readfds,&writefds,&exceptfds,tvp); if (rsel==-1) { if (errno == EINTR) { @@ -606,7 +710,7 @@ int adns_wait(adns_state ads, adns_afterselect(ads,maxfd,&readfds,&writefds,&exceptfds,0); } } - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); return r; } @@ -622,6 +726,6 @@ int adns_check(adns_state ads, if (!r) adns__autosys(ads,now); r= adns__internal_check(ads,query_io,answer_r,context_r); - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); return r; }