X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=adns.git;a=blobdiff_plain;f=src%2Fevent.c;h=04ba26bdcb1a10797af4ecd2b7ec4f7b2992865e;hp=a1641c630a1d0307d62fffc6f6e6c61e39a3844d;hb=13d889da08a24f8999f0f98fff913bec6c9b71d2;hpb=2953d358511ac5d196362f6b339c010d4e9cae3e diff --git a/src/event.c b/src/event.c index a1641c6..04ba26b 100644 --- a/src/event.c +++ b/src/event.c @@ -5,12 +5,11 @@ * - 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 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 @@ -44,9 +43,6 @@ /* TCP connection management. */ static void tcp_close(adns_state ads) { - int serv; - - serv= ads->tcpserver; close(ads->tcpsocket); ads->tcpsocket= -1; ads->tcprecv.used= ads->tcprecv_skip= ads->tcpsend.used= 0; @@ -54,11 +50,18 @@ static void tcp_close(adns_state ads) { void adns__tcp_broken(adns_state ads, const char *what, const char *why) { int serv; + adns_query qu; assert(ads->tcpstate == server_connecting || ads->tcpstate == server_ok); serv= ads->tcpserver; 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; @@ -76,9 +79,24 @@ static void tcp_connected(adns_state ads, struct timeval 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++) { @@ -98,23 +116,24 @@ void adns__tcp_tryconnect(adns_state ads, struct timeval now) { 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); return; } @@ -124,7 +143,7 @@ void adns__tcp_tryconnect(adns_state ads, struct timeval now) { return; } adns__tcp_broken(ads,"connect",strerror(errno)); - ads->tcpstate= server_disconnected; + tcp_broken_events(ads); } } @@ -143,6 +162,17 @@ 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; @@ -185,12 +215,7 @@ static void timeouts_queue(adns_state ads, int act, if (!timercmp(&now,&qu->timeout,>)) { inter_maxtoabs(tv_io,tvbuf,now,qu->timeout); } else { - if (!act) { - tvbuf->tv_sec= 0; - tvbuf->tv_usec= 0; - *tv_io= tvbuf; - return; - } + if (!act) { inter_immed(tv_io,tvbuf); return; } LIST_UNLINK(*queue,qu); if (qu->state != query_tosend) { adns__query_fail(qu,adns_s_timeout); @@ -205,22 +230,14 @@ static void timeouts_queue(adns_state ads, int act, static void tcp_events(adns_state ads, int act, struct timeval **tv_io, struct timeval *tvbuf, struct timeval now) { - adns_query qu, nqu; - for (;;) { switch (ads->tcpstate) { case 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; + 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: @@ -231,7 +248,7 @@ static void tcp_events(adns_state ads, int act, timevaladd(&ads->tcptimeout,TCPIDLEMS); } case server_connecting: /* fall through */ - if (!timercmp(&now,&ads->tcptimeout,>)) { + if (!act || !timercmp(&now,&ads->tcptimeout,>)) { inter_maxtoabs(tv_io,tvbuf,now,ads->tcptimeout); return; } { @@ -253,6 +270,7 @@ static void tcp_events(adns_state ads, int act, abort(); } } + return; } void adns__timeouts(adns_state ads, int act, @@ -286,27 +304,35 @@ 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) assert(MAX_POLLFDS==2); - pollfds_buf[0].fd= ads->udpsocket; - pollfds_buf[0].events= POLLIN; - pollfds_buf[0].revents= 0; + ADD_POLLFD(ads->udpsocket, 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) { @@ -318,12 +344,13 @@ int adns_processreadable(adns_state ads, int fd, const struct timeval *now) { 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]); @@ -340,7 +367,8 @@ 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); @@ -357,9 +385,9 @@ 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(); } @@ -377,7 +405,8 @@ int adns_processreadable(adns_state ads, int fd, const struct timeval *now) { } if (udpaddrlen != sizeof(udpaddr)) { adns__diag(ads,-1,0,"datagram received with wrong address length %d" - " (expected %d)", udpaddrlen,sizeof(udpaddr)); + " (expected %lu)", udpaddrlen, + (unsigned long)sizeof(udpaddr)); continue; } if (udpaddr.sin_family != AF_INET) { @@ -386,13 +415,14 @@ int adns_processreadable(adns_state ads, int fd, const struct timeval *now) { 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); + 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__sockaddr_equal_p(&ads->servers[serv].addr.sa, + (const struct sockaddr *)&udpaddr); serv++); if (serv >= ads->nservers) { adns__warn(ads,-1,0,"datagram received from unknown nameserver %s", @@ -415,6 +445,7 @@ 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; @@ -437,8 +468,8 @@ 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); @@ -452,7 +483,9 @@ 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(); } @@ -462,10 +495,12 @@ xit: 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: @@ -482,7 +517,8 @@ int adns_processexceptional(adns_state ads, int fd, const struct timeval *now) { 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; @@ -493,7 +529,8 @@ 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); } } @@ -510,9 +547,12 @@ 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 } } @@ -531,8 +571,8 @@ 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); @@ -586,6 +626,7 @@ void adns_globalsystemfailure(adns_state ads) { adns__tcp_broken(ads,0,0); break; case server_disconnected: + case server_broken: break; default: abort(); @@ -609,7 +650,7 @@ 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; i