adnshost improvements - now runs for at least one query.

[adns] / src / event.c

diff --git a/src/event.c b/src/event.c
index f84204d9c2c1b80b42e8044f4413bc7f49c1aaed..b2da291e0856ee77669393638b8dd1c409ca6573 100644 (file)
--- a/src/event.c
+++ b/src/event.c
@@ -5,7 +5,12 @@
  * - user-visible check/wait and event-loop-related functions
  */
 /*
- *  This file is part of adns, which is Copyright (C) 1997-1999 Ian Jackson
+ *  This file is
+ *    Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk>
+ *
+ *  It is part of adns, which is
+ *    Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk>
+ *    Copyright (C) 1999 Tony Finch <dot@dotat.at>
  *  
  *  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
@@ -42,8 +47,9 @@ void adns__tcp_closenext(adns_state ads) {
   
   serv= ads->tcpserver;
   close(ads->tcpsocket);
+  ads->tcpsocket= -1;
   ads->tcpstate= server_disconnected;
-  ads->tcprecv.used= ads->tcpsend.used= 0;
+  ads->tcprecv.used= ads->tcprecv_skip= ads->tcpsend.used= 0;
   ads->tcpserver= (serv+1)%ads->nservers;
 }
 
@@ -92,6 +98,7 @@ void adns__tcp_tryconnect(adns_state ads, struct timeval now) {
     assert(ads->tcpstate == server_disconnected);
     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; }
@@ -191,18 +198,18 @@ void adns__timeouts(adns_state ads, int act,
 void adns_firsttimeout(adns_state ads,
                       struct timeval **tv_io, struct timeval *tvbuf,
                       struct timeval now) {
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,0,cc_entex);
   adns__timeouts(ads, 0, tv_io,tvbuf, now);
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,0,cc_entex);
 }
 
 void adns_processtimeouts(adns_state ads, const struct timeval *now) {
   struct timeval tv_buf;
 
-  adns__consistency(ads,cc_entex);
+  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,cc_entex);
+  adns__consistency(ads,0,cc_entex);
 }
 
 /* fd handling functions.  These are the top-level of the real work of
@@ -235,11 +242,11 @@ int adns__pollfds(adns_state ads, struct pollfd pollfds_buf[MAX_POLLFDS]) {
 }
 
 int adns_processreadable(adns_state ads, int fd, const struct timeval *now) {
-  int skip, want, dgramlen, r, udpaddrlen, serv;
+  int want, dgramlen, r, udpaddrlen, serv, old_skip;
   byte udpbuf[DNS_MAXUDP];
   struct sockaddr_in udpaddr;
   
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,0,cc_entex);
 
   switch (ads->tcpstate) {
   case server_disconnected:
@@ -247,22 +254,26 @@ int adns_processreadable(adns_state ads, int fd, const struct timeval *now) {
     break;
   case server_ok:
     if (fd != ads->tcpsocket) break;
-    skip= 0;
+    assert(!ads->tcprecv_skip);
     for (;;) {
-      if (ads->tcprecv.used<skip+2) {
-       want= 2;
-      } else {
-       dgramlen= (ads->tcprecv.buf[skip]<<8) | ads->tcprecv.buf[skip+1];
-       if (ads->tcprecv.used<skip+2+dgramlen) {
-         want= 2+dgramlen;
+      if (ads->tcprecv.used >= ads->tcprecv_skip+2) {
+       dgramlen= ((ads->tcprecv.buf[ads->tcprecv_skip]<<8) |
+                  ads->tcprecv.buf[ads->tcprecv_skip+1]);
+       if (ads->tcprecv.used >= ads->tcprecv_skip+2+dgramlen) {
+         old_skip= ads->tcprecv_skip;
+         ads->tcprecv_skip += 2+dgramlen;
+         adns__procdgram(ads, ads->tcprecv.buf+old_skip+2,
+                         dgramlen, ads->tcpserver, 1,*now);
+         continue;
        } else {
-         adns__procdgram(ads,ads->tcprecv.buf+skip+2,dgramlen,ads->tcpserver,1,*now);
-         skip+= 2+dgramlen; continue;
+         want= 2+dgramlen;
        }
+      } else {
+       want= 2;
       }
-      ads->tcprecv.used -= skip;
-      memmove(ads->tcprecv.buf,ads->tcprecv.buf+skip,ads->tcprecv.used);
-      skip= 0;
+      ads->tcprecv.used -= ads->tcprecv_skip;
+      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);
       if (ads->tcprecv.used == ads->tcprecv.avail) continue;
@@ -325,14 +336,14 @@ int adns_processreadable(adns_state ads, int fd, const struct timeval *now) {
   }
   r= 0;
 xit:
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,0,cc_entex);
   return r;
 }
 
 int adns_processwriteable(adns_state ads, int fd, const struct timeval *now) {
   int r;
   
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,0,cc_entex);
 
   switch (ads->tcpstate) {
   case server_disconnected:
@@ -340,6 +351,7 @@ int adns_processwriteable(adns_state ads, int fd, const struct timeval *now) {
   case server_connecting:
     if (fd != ads->tcpsocket) break;
     assert(ads->tcprecv.used==0);
+    assert(ads->tcprecv_skip==0);
     for (;;) {
       if (!adns__vbuf_ensure(&ads->tcprecv,1)) { r= ENOMEM; goto xit; }
       r= read(ads->tcpsocket,&ads->tcprecv.buf,1);
@@ -378,12 +390,12 @@ int adns_processwriteable(adns_state ads, int fd, const struct timeval *now) {
   }
   r= 0;
 xit:
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,0,cc_entex);
   return r;
 }
   
 int adns_processexceptional(adns_state ads, int fd, const struct timeval *now) {
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,0,cc_entex);
   switch (ads->tcpstate) {
   case server_disconnected:
     break;
@@ -395,7 +407,7 @@ int adns_processexceptional(adns_state ads, int fd, const struct timeval *now) {
   default:
     abort();
   }
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,0,cc_entex);
   return 0;
 }
 
@@ -446,7 +458,7 @@ void adns_beforeselect(adns_state ads, int *maxfd_io, fd_set *readfds_io,
   struct pollfd pollfds[MAX_POLLFDS];
   int i, fd, maxfd, npollfds;
   
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,0,cc_entex);
 
   if (tv_mod && (!*tv_mod || (*tv_mod)->tv_sec || (*tv_mod)->tv_usec)) {
     /* The caller is planning to sleep. */
@@ -467,7 +479,7 @@ void adns_beforeselect(adns_state ads, int *maxfd_io, fd_set *readfds_io,
   *maxfd_io= maxfd;
 
 xit:
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,0,cc_entex);
 }
 
 void adns_afterselect(adns_state ads, int maxfd, const fd_set *readfds,
@@ -477,7 +489,7 @@ void adns_afterselect(adns_state ads, int maxfd, const fd_set *readfds,
   struct pollfd pollfds[MAX_POLLFDS];
   int npollfds, i;
 
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,0,cc_entex);
   adns__must_gettimeofday(ads,&now,&tv_buf);
   if (!now) goto xit;
   adns_processtimeouts(ads,now);
@@ -489,13 +501,13 @@ void adns_afterselect(adns_state ads, int maxfd, const fd_set *readfds,
                 maxfd,readfds,writefds,exceptfds,
                 *now, 0);
 xit:
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,0,cc_entex);
 }
 
 /* General helpful functions. */
 
 void adns_globalsystemfailure(adns_state ads) {
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,0,cc_entex);
 
   while (ads->timew.head) {
     adns__query_fail(ads->timew.head, adns_s_systemfail);
@@ -511,28 +523,33 @@ void adns_globalsystemfailure(adns_state ads) {
   default:
     abort();
   }
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,0,cc_entex);
 }
 
 int adns_processany(adns_state ads) {
-  int r;
+  int r, i;
   struct timeval now;
   struct pollfd pollfds[MAX_POLLFDS];
   int npollfds;
 
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,0,cc_entex);
 
   r= gettimeofday(&now,0);
   if (!r) adns_processtimeouts(ads,&now);
 
+  /* We just use adns__fdevents to loop over the fd's trying them.
+   * This seems more sensible than calling select, since we're most
+   * likely just to want to do a read on one or two fds anyway.
+   */
   npollfds= adns__pollfds(ads,pollfds);
+  for (i=0; i<npollfds; i++) pollfds[i].revents= pollfds[i].events;
   adns__fdevents(ads,
                 pollfds,npollfds,
                 0,0,0,0,
                 now,&r);
 
-  adns__consistency(ads,cc_entex);
-  return r;
+  adns__consistency(ads,0,cc_entex);
+  return 0;
 }
 
 void adns__autosys(adns_state ads, struct timeval now) {
@@ -540,18 +557,18 @@ void adns__autosys(adns_state ads, struct timeval now) {
   adns_processany(ads);
 }
 
-static int internal_check(adns_state ads,
-                         adns_query *query_io,
-                         adns_answer **answer,
-                         void **context_r) {
+int adns__internal_check(adns_state ads,
+                        adns_query *query_io,
+                        adns_answer **answer,
+                        void **context_r) {
   adns_query qu;
 
   qu= *query_io;
   if (!qu) {
-    if (!ads->output.head) return EWOULDBLOCK;
+    if (!ads->output.head) return EAGAIN;
     qu= ads->output.head;
   } else {
-    if (qu->id>=0) return EWOULDBLOCK;
+    if (qu->id>=0) return EAGAIN;
   }
   LIST_UNLINK(ads->output,qu);
   *answer= qu->answer;
@@ -569,10 +586,10 @@ int adns_wait(adns_state ads,
   fd_set readfds, writefds, exceptfds;
   struct timeval tvbuf, *tvp;
   
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,*query_io,cc_entex);
   for (;;) {
-    r= internal_check(ads,query_io,answer_r,context_r);
-    if (r != EWOULDBLOCK) break;
+    r= adns__internal_check(ads,query_io,answer_r,context_r);
+    if (r != EAGAIN) break;
     maxfd= 0; tvp= 0;
     FD_ZERO(&readfds); FD_ZERO(&writefds); FD_ZERO(&exceptfds);
     adns_beforeselect(ads,&maxfd,&readfds,&writefds,&exceptfds,&tvp,&tvbuf,0);
@@ -589,7 +606,7 @@ int adns_wait(adns_state ads,
       adns_afterselect(ads,maxfd,&readfds,&writefds,&exceptfds,0);
     }
   }
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,0,cc_entex);
   return r;
 }
 
@@ -600,11 +617,11 @@ int adns_check(adns_state ads,
   struct timeval now;
   int r;
   
-  adns__consistency(ads,cc_entex);
+  adns__consistency(ads,*query_io,cc_entex);
   r= gettimeofday(&now,0);
   if (!r) adns__autosys(ads,now);
 
-  r= internal_check(ads,query_io,answer_r,context_r);
-  adns__consistency(ads,cc_entex);
+  r= adns__internal_check(ads,query_io,answer_r,context_r);
+  adns__consistency(ads,0,cc_entex);
   return r;
 }