libs/adns/src/check.c

   1 /*
   2  * check.c
   3  * - consistency checks
   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 "internal.h"
  29 #include <stdlib.h>
  30
  31 void adns_checkconsistency(adns_state ads, adns_query qu) {
  32   adns__consistency(ads,qu,cc_user);
  33 }
  34
  35 #define DLIST_CHECK(list, nodevar, part, body)                                  \
  36   if ((list).head) {                                                            \
  37     assert(! (list).head->part back);                                           \
  38     for ((nodevar)= (list).head; (nodevar); (nodevar)= (nodevar)->part next) {  \
  39       assert((nodevar)->part next                                               \
  40              ? (nodevar) == (nodevar)->part next->part back                     \
  41              : (nodevar) == (list).tail);                                       \
  42       body                                                                      \
  43     }                                                                           \
  44   }
  45
  46 #define DLIST_ASSERTON(node, nodevar, list, part)                               \
  47   do {                                                                          \
  48     for ((nodevar)= (list).head;                                                \
  49          (nodevar) != (node);                                                   \
  50          (nodevar)= (nodevar)->part next) {                                     \
  51       assert((nodevar));                                                        \
  52     }                                                                           \
  53   } while(0)
  54
  55 static void checkc_query_alloc(adns_state ads, adns_query qu) {
  56   allocnode *an;
  57
  58   DLIST_CHECK(qu->allocations, an, , {
  59   });
  60 }
  61
  62 static void checkc_query(adns_state ads, adns_query qu) {
  63   adns_query child;
  64
  65   assert(qu->udpnextserver < ads->nservers);
  66   assert(!(qu->udpsent & (~0UL << ads->nservers)));
  67   assert(qu->search_pos <= ads->nsearchlist);
  68   if (qu->parent) DLIST_ASSERTON(qu, child, qu->parent->children, siblings.);
  69 }
  70
  71 static void checkc_notcpbuf(adns_state ads) {
  72   assert(!ads->tcpsend.used);
  73   assert(!ads->tcprecv.used);
  74   assert(!ads->tcprecv_skip);
  75 }
  76
  77 static void checkc_global(adns_state ads) {
  78   int i;
  79
  80   assert(ads->udpsocket >= 0);
  81
  82   for (i=0; i<ads->nsortlist; i++)
  83     assert(!(ads->sortlist[i].base.s_addr & ~ads->sortlist[i].mask.s_addr));
  84
  85   assert(ads->tcpserver >= 0 && ads->tcpserver < ads->nservers);
  86
  87   switch (ads->tcpstate) {
  88   case server_connecting:
  89     assert(ads->tcpsocket >= 0);
  90     checkc_notcpbuf(ads);
  91     break;
  92   case server_disconnected:
  93   case server_broken:
  94     assert(ads->tcpsocket == -1);
  95     checkc_notcpbuf(ads);
  96     break;
  97   case server_ok:
  98     assert(ads->tcpsocket >= 0);
  99     assert(ads->tcprecv_skip <= ads->tcprecv.used);
 100     break;
 101   default:
 102     assert(!"ads->tcpstate value");
 103   }
 104
 105   assert(ads->searchlist || !ads->nsearchlist);
 106 }
 107
 108 static void checkc_queue_udpw(adns_state ads) {
 109   adns_query qu;
 110
 111   DLIST_CHECK(ads->udpw, qu, , {
 112     assert(qu->state==query_tosend);
 113     assert(qu->retries <= UDPMAXRETRIES);
 114     assert(qu->udpsent);
 115     assert(!qu->children.head && !qu->children.tail);
 116     checkc_query(ads,qu);
 117     checkc_query_alloc(ads,qu);
 118   });
 119 }
 120
 121 static void checkc_queue_tcpw(adns_state ads) {
 122   adns_query qu;
 123
 124   DLIST_CHECK(ads->tcpw, qu, , {
 125     assert(qu->state==query_tcpw);
 126     assert(!qu->children.head && !qu->children.tail);
 127     assert(qu->retries <= ads->nservers+1);
 128     checkc_query(ads,qu);
 129     checkc_query_alloc(ads,qu);
 130   });
 131 }
 132
 133 static void checkc_queue_childw(adns_state ads) {
 134   adns_query parent, child;
 135
 136   DLIST_CHECK(ads->childw, parent, , {
 137     assert(parent->state == query_childw);
 138     assert(parent->children.head);
 139     DLIST_CHECK(parent->children, child, siblings., {
 140       assert(child->parent == parent);
 141       assert(child->state != query_done);
 142     });
 143     checkc_query(ads,parent);
 144     checkc_query_alloc(ads,parent);
 145   });
 146 }
 147
 148 static void checkc_queue_output(adns_state ads) {
 149   adns_query qu;
 150
 151   DLIST_CHECK(ads->output, qu, , {
 152     assert(qu->state == query_done);
 153     assert(!qu->children.head && !qu->children.tail);
 154     assert(!qu->parent);
 155     assert(!qu->allocations.head && !qu->allocations.tail);
 156     checkc_query(ads,qu);
 157   });
 158 }
 159
 160 void adns__consistency(adns_state ads, adns_query qu, consistency_checks cc) {
 161   adns_query search;
 162
 163   switch (cc) {
 164   case cc_user:
 165     break;
 166   case cc_entex:
 167     if (!(ads->iflags & adns_if_checkc_entex)) return;
 168     break;
 169   case cc_freq:
 170     if ((ads->iflags & adns_if_checkc_freq) != adns_if_checkc_freq) return;
 171     break;
 172   default:
 173     abort();
 174   }
 175
 176   checkc_global(ads);
 177   checkc_queue_udpw(ads);
 178   checkc_queue_tcpw(ads);
 179   checkc_queue_childw(ads);
 180   checkc_queue_output(ads);
 181
 182   if (qu) {
 183     switch (qu->state) {
 184     case query_tosend:
 185       DLIST_ASSERTON(qu, search, ads->udpw, );
 186       break;
 187     case query_tcpw:
 188       DLIST_ASSERTON(qu, search, ads->tcpw, );
 189       break;
 190     case query_childw:
 191       DLIST_ASSERTON(qu, search, ads->childw, );
 192       break;
 193     case query_done:
 194       DLIST_ASSERTON(qu, search, ads->output, );
 195       break;
 196     default:
 197       assert(!"specific query state");
 198     }
 199   }
 200 }