3 * - overall query management (allocation, completion)
4 * - per-query memory management
5 * - query submission and cancellation (user-visible and internal)
8 * This file is part of adns, which is Copyright (C) 1997-1999 Ian Jackson
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2, or (at your option)
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software Foundation,
22 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
36 static adns_query
query_alloc(adns_state ads
, const typeinfo
*typei
,
37 adns_queryflags flags
, struct timeval now
) {
38 /* Allocate a virgin query and return it. */
41 qu
= malloc(sizeof(*qu
)); if (!qu
) return 0;
42 qu
->answer
= malloc(sizeof(*qu
->answer
)); if (!qu
->answer
) { free(qu
); return 0; }
46 qu
->back
= qu
->next
= qu
->parent
= 0;
47 LIST_INIT(qu
->children
);
48 LINK_INIT(qu
->siblings
);
49 LIST_INIT(qu
->allocations
);
50 qu
->interim_allocd
= 0;
51 qu
->final_allocspace
= 0;
56 adns__vbuf_init(&qu
->vb
);
59 qu
->cname_dglen
= qu
->cname_begin
= 0;
61 adns__vbuf_init(&qu
->search_vb
);
62 qu
->search_origlen
= qu
->search_pos
= qu
->search_doneabs
= 0;
68 qu
->udpsent
= qu
->tcpfailed
= 0;
69 timerclear(&qu
->timeout
);
70 qu
->expires
= now
.tv_sec
+ MAXTTLBELIEVE
;
72 memset(&qu
->ctx
,0,sizeof(qu
->ctx
));
74 qu
->answer
->status
= adns_s_ok
;
76 qu
->answer
->type
= typei
->type
;
77 qu
->answer
->expires
= -1;
80 qu
->answer
->rrsz
= typei
->rrsz
;
85 static void query_submit(adns_state ads
, adns_query qu
,
86 const typeinfo
*typei
, vbuf
*qumsg_vb
, int id
,
87 adns_queryflags flags
, struct timeval now
) {
88 /* Fills in the query message in for a previously-allocated query,
89 * and submits it. Cannot fail.
93 adns__vbuf_init(qumsg_vb
);
95 qu
->query_dgram
= malloc(qu
->vb
.used
);
96 if (!qu
->query_dgram
) { adns__query_fail(qu
,adns_s_nomemory
); return; }
99 qu
->query_dglen
= qu
->vb
.used
;
100 memcpy(qu
->query_dgram
,qu
->vb
.buf
,qu
->vb
.used
);
102 adns__query_udp(qu
,now
);
103 adns__autosys(ads
,now
);
106 adns_status
adns__internal_submit(adns_state ads
, adns_query
*query_r
,
107 const typeinfo
*typei
, vbuf
*qumsg_vb
, int id
,
108 adns_queryflags flags
, struct timeval now
,
109 const qcontext
*ctx
) {
112 qu
= query_alloc(ads
,typei
,flags
,now
);
113 if (!qu
) { adns__vbuf_free(qumsg_vb
); return adns_s_nomemory
; }
116 memcpy(&qu
->ctx
,ctx
,sizeof(qu
->ctx
));
117 query_submit(ads
,qu
, typei
,qumsg_vb
,id
,flags
,now
);
122 static void query_simple(adns_state ads
, adns_query qu
,
123 const char *owner
, int ol
,
124 const typeinfo
*typei
, adns_queryflags flags
,
125 struct timeval now
) {
130 adns__vbuf_init(&vb
);
132 stat
= adns__mkquery(ads
,&vb
,&id
, owner
,ol
, typei
,flags
);
133 if (stat
) { adns__query_fail(qu
,stat
); return; }
135 query_submit(ads
,qu
, typei
,&vb
,id
, flags
,now
);
138 void adns__search_next(adns_state ads
, adns_query qu
, struct timeval now
) {
139 const char *nextentry
;
142 if (qu
->search_doneabs
<0) {
144 qu
->search_doneabs
= 1;
146 if (qu
->search_pos
>= ads
->nsearchlist
) {
147 if (qu
->search_doneabs
) {
148 stat
= adns_s_nxdomain
; goto x_fail
;
152 qu
->search_doneabs
= 1;
155 nextentry
= ads
->searchlist
[qu
->search_pos
++];
159 qu
->search_vb
.used
= qu
->search_origlen
;
161 if (!adns__vbuf_append(&qu
->search_vb
,".",1) ||
162 !adns__vbuf_appendstr(&qu
->search_vb
,nextentry
)) {
163 stat
= adns_s_nomemory
; goto x_fail
;
167 free(qu
->query_dgram
);
168 qu
->query_dgram
= 0; qu
->query_dglen
= 0;
170 query_simple(ads
,qu
, qu
->search_vb
.buf
, qu
->search_vb
.used
, qu
->typei
, qu
->flags
, now
);
174 adns__query_fail(qu
,stat
);
177 int adns_submit(adns_state ads
,
180 adns_queryflags flags
,
182 adns_query
*query_r
) {
185 const typeinfo
*typei
;
190 typei
= adns__findtype(type
);
191 if (!typei
) return adns_s_unknownrrtype
;
193 r
= gettimeofday(&now
,0); if (r
) goto x_errno
;
194 qu
= query_alloc(ads
,typei
,flags
,now
); if (!qu
) goto x_errno
;
196 qu
->ctx
.ext
= context
;
198 memset(&qu
->ctx
.info
,0,sizeof(qu
->ctx
.info
));
203 if (!ol
) { stat
= adns_s_querydomaininvalid
; goto x_adnsfail
; }
204 if (ol
>DNS_MAXDOMAIN
+1) { stat
= adns_s_querydomaintoolong
; goto x_adnsfail
; }
206 if (ol
>=2 && owner
[ol
-1]=='.' && owner
[ol
-2]!='\\') { flags
&= ~adns_qf_search
; ol
--; }
208 if (flags
& adns_qf_search
) {
209 r
= adns__vbuf_append(&qu
->search_vb
,owner
,ol
);
210 if (!r
) { stat
= adns_s_nomemory
; goto x_adnsfail
; }
212 for (ndots
=0, p
=owner
; (p
= strchr(p
,'.')); p
++, ndots
++);
213 qu
->search_doneabs
= (ndots
>= ads
->searchndots
) ?
-1 : 0;
214 qu
->search_origlen
= ol
;
215 adns__search_next(ads
,qu
,now
);
217 query_simple(ads
,qu
, owner
,ol
, typei
,flags
, now
);
222 adns__query_fail(qu
,stat
);
231 int adns_synchronous(adns_state ads
,
234 adns_queryflags flags
,
235 adns_answer
**answer_r
) {
239 r
= adns_submit(ads
,owner
,type
,flags
,0,&qu
);
242 r
= adns_wait(ads
,&qu
,answer_r
,0);
243 if (r
) adns_cancel(qu
);
248 static void *alloc_common(adns_query qu
, size_t sz
) {
251 if (!sz
) return qu
; /* Any old pointer will do */
252 assert(!qu
->final_allocspace
);
253 an
= malloc(MEM_ROUND(MEM_ROUND(sizeof(*an
)) + sz
));
255 LIST_LINK_TAIL(qu
->allocations
,an
);
256 return (byte
*)an
+ MEM_ROUND(sizeof(*an
));
259 void *adns__alloc_interim(adns_query qu
, size_t sz
) {
261 qu
->interim_allocd
+= sz
;
262 return alloc_common(qu
,sz
);
265 void *adns__alloc_mine(adns_query qu
, size_t sz
) {
266 return alloc_common(qu
,MEM_ROUND(sz
));
269 void adns__transfer_interim(adns_query from
, adns_query to
, void *block
, size_t sz
) {
273 an
= (void*)((byte
*)block
- MEM_ROUND(sizeof(*an
)));
275 assert(!to
->final_allocspace
);
276 assert(!from
->final_allocspace
);
278 LIST_UNLINK(from
->allocations
,an
);
279 LIST_LINK_TAIL(to
->allocations
,an
);
281 from
->interim_allocd
-= sz
;
282 to
->interim_allocd
+= sz
;
284 if (to
->expires
> from
->expires
) to
->expires
= from
->expires
;
287 void *adns__alloc_final(adns_query qu
, size_t sz
) {
288 /* When we're in the _final stage, we _subtract_ from interim_alloc'd
289 * each allocation, and use final_allocspace to point to the next free
295 rp
= qu
->final_allocspace
;
297 qu
->interim_allocd
-= sz
;
298 assert(qu
->interim_allocd
>=0);
299 qu
->final_allocspace
= (byte
*)rp
+ sz
;
303 static void cancel_children(adns_query qu
) {
304 adns_query cqu
, ncqu
;
306 for (cqu
= qu
->children
.head
; cqu
; cqu
= ncqu
) {
307 ncqu
= cqu
->siblings
.next
;
310 LIST_INIT(qu
->children
);
313 void adns__reset_cnameonly(adns_query qu
) {
314 assert(!qu
->final_allocspace
);
318 qu
->interim_allocd
= qu
->answer
->cname ?
MEM_ROUND(strlen(qu
->answer
->cname
)+1) : 0;
321 static void free_query_allocs(adns_query qu
) {
325 for (an
= qu
->allocations
.head
; an
; an
= ann
) { ann
= an
->next
; free(an
); }
326 adns__vbuf_free(&qu
->vb
);
329 void adns_cancel(adns_query qu
) {
331 case query_udp
: case query_tcpwait
: case query_tcpsent
:
332 LIST_UNLINK(qu
->ads
->timew
,qu
);
335 LIST_UNLINK(qu
->ads
->childw
,qu
);
338 LIST_UNLINK(qu
->ads
->output
,qu
);
343 free_query_allocs(qu
);
348 void adns__update_expires(adns_query qu
, unsigned long ttl
, struct timeval now
) {
351 assert(ttl
<= MAXTTLBELIEVE
);
352 max
= now
.tv_sec
+ ttl
;
353 if (qu
->expires
< max
) return;
357 static void makefinal_query(adns_query qu
) {
363 if (qu
->interim_allocd
) {
364 ans
= realloc(qu
->answer
, MEM_ROUND(MEM_ROUND(sizeof(*ans
)) + qu
->interim_allocd
));
365 if (!ans
) goto x_nomem
;
369 qu
->final_allocspace
= (byte
*)ans
+ MEM_ROUND(sizeof(*ans
));
370 adns__makefinal_str(qu
,&ans
->cname
);
373 adns__makefinal_block(qu
, &ans
->rrs
.untyped
, ans
->nrrs
*ans
->rrsz
);
375 for (rrn
=0; rrn
<ans
->nrrs
; rrn
++)
376 qu
->typei
->makefinal(qu
, ans
->rrs
.bytes
+ rrn
*ans
->rrsz
);
379 free_query_allocs(qu
);
383 qu
->answer
->status
= adns_s_nomemory
;
384 qu
->answer
->cname
= 0;
385 adns__reset_cnameonly(qu
);
386 free_query_allocs(qu
);
389 void adns__query_done(adns_query qu
) {
396 if (ans
->nrrs
&& qu
->typei
->diff_needswap
) {
397 if (!adns__vbuf_ensure(&qu
->vb
,qu
->typei
->rrsz
)) {
398 adns__query_fail(qu
,adns_s_nomemory
);
401 adns__isort(ans
->rrs
.bytes
, ans
->nrrs
, ans
->rrsz
,
403 (int(*)(void*, const void*, const void*))qu
->typei
->diff_needswap
,
407 ans
->expires
= qu
->expires
;
410 LIST_UNLINK_PART(parent
->children
,qu
,siblings
.);
411 qu
->ctx
.callback(parent
,qu
);
412 free_query_allocs(qu
);
416 LIST_LINK_TAIL(qu
->ads
->output
,qu
);
420 void adns__query_fail(adns_query qu
, adns_status stat
) {
421 adns__reset_cnameonly(qu
);
422 qu
->answer
->status
= stat
;
423 adns__query_done(qu
);
426 void adns__makefinal_str(adns_query qu
, char **strp
) {
428 char *before
, *after
;
433 after
= adns__alloc_final(qu
,l
);
434 memcpy(after
,before
,l
);
438 void adns__makefinal_block(adns_query qu
, void **blpp
, size_t sz
) {
439 void *before
, *after
;
443 after
= adns__alloc_final(qu
,sz
);
444 memcpy(after
,before
,sz
);