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