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.
35 static adns_query
query_alloc(adns_state ads
, const typeinfo
*typei
,
36 adns_queryflags flags
, struct timeval now
) {
37 /* Allocate a virgin query and return it. */
40 qu
= malloc(sizeof(*qu
)); if (!qu
) return 0;
41 qu
->answer
= malloc(sizeof(*qu
->answer
)); if (!qu
->answer
) { free(qu
); return 0; }
44 qu
->state
= query_tosend
;
45 qu
->back
= qu
->next
= qu
->parent
= 0;
46 LIST_INIT(qu
->children
);
47 LINK_INIT(qu
->siblings
);
48 LIST_INIT(qu
->allocations
);
49 qu
->interim_allocd
= 0;
50 qu
->preserved_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
;
75 qu
->answer
->cname
= qu
->answer
->owner
= 0;
76 qu
->answer
->type
= typei
->type
;
77 qu
->answer
->expires
= -1;
79 qu
->answer
->rrs
.untyped
= 0;
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_send(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 static int save_owner(adns_query qu
, const char *owner
, int ol
) {
178 /* Returns 1 if OK, otherwise there was no memory. */
184 ans
->owner
= adns__alloc_preserved(qu
,ol
+1); if (!ans
->owner
) return 0;
186 memcpy(ans
->owner
,owner
,ol
);
191 int adns_submit(adns_state ads
,
194 adns_queryflags flags
,
196 adns_query
*query_r
) {
199 const typeinfo
*typei
;
204 adns__consistency(ads
,0,cc_entex
);
206 typei
= adns__findtype(type
);
207 if (!typei
) return ENOSYS
;
209 r
= gettimeofday(&now
,0); if (r
) goto x_errno
;
210 qu
= query_alloc(ads
,typei
,flags
,now
); if (!qu
) goto x_errno
;
212 qu
->ctx
.ext
= context
;
214 memset(&qu
->ctx
.info
,0,sizeof(qu
->ctx
.info
));
219 if (!ol
) { stat
= adns_s_querydomaininvalid
; goto x_adnsfail
; }
220 if (ol
>DNS_MAXDOMAIN
+1) { stat
= adns_s_querydomaintoolong
; goto x_adnsfail
; }
222 if (ol
>=1 && owner
[ol
-1]=='.' && (ol
<2 || owner
[ol
-2]!='\\')) {
223 flags
&= ~adns_qf_search
;
227 if (flags
& adns_qf_search
) {
228 r
= adns__vbuf_append(&qu
->search_vb
,owner
,ol
);
229 if (!r
) { stat
= adns_s_nomemory
; goto x_adnsfail
; }
231 for (ndots
=0, p
=owner
; (p
= strchr(p
,'.')); p
++, ndots
++);
232 qu
->search_doneabs
= (ndots
>= ads
->searchndots
) ?
-1 : 0;
233 qu
->search_origlen
= ol
;
234 adns__search_next(ads
,qu
,now
);
236 if (flags
& adns_qf_owner
) {
237 if (!save_owner(qu
,owner
,ol
)) { stat
= adns_s_nomemory
; goto x_adnsfail
; }
239 query_simple(ads
,qu
, owner
,ol
, typei
,flags
, now
);
241 adns__consistency(ads
,qu
,cc_entex
);
245 adns__query_fail(qu
,stat
);
246 adns__consistency(ads
,qu
,cc_entex
);
252 adns__consistency(ads
,0,cc_entex
);
256 int adns_synchronous(adns_state ads
,
259 adns_queryflags flags
,
260 adns_answer
**answer_r
) {
264 r
= adns_submit(ads
,owner
,type
,flags
,0,&qu
);
267 r
= adns_wait(ads
,&qu
,answer_r
,0);
268 if (r
) adns_cancel(qu
);
273 static void *alloc_common(adns_query qu
, size_t sz
) {
276 if (!sz
) return qu
; /* Any old pointer will do */
277 assert(!qu
->final_allocspace
);
278 an
= malloc(MEM_ROUND(MEM_ROUND(sizeof(*an
)) + sz
));
280 LIST_LINK_TAIL(qu
->allocations
,an
);
281 return (byte
*)an
+ MEM_ROUND(sizeof(*an
));
284 void *adns__alloc_interim(adns_query qu
, size_t sz
) {
288 rv
= alloc_common(qu
,sz
);
290 qu
->interim_allocd
+= sz
;
294 void *adns__alloc_preserved(adns_query qu
, size_t sz
) {
298 rv
= adns__alloc_interim(qu
,sz
);
300 qu
->preserved_allocd
+= sz
;
304 void *adns__alloc_mine(adns_query qu
, size_t sz
) {
305 return alloc_common(qu
,MEM_ROUND(sz
));
308 void adns__transfer_interim(adns_query from
, adns_query to
, void *block
, size_t sz
) {
312 an
= (void*)((byte
*)block
- MEM_ROUND(sizeof(*an
)));
314 assert(!to
->final_allocspace
);
315 assert(!from
->final_allocspace
);
317 LIST_UNLINK(from
->allocations
,an
);
318 LIST_LINK_TAIL(to
->allocations
,an
);
320 from
->interim_allocd
-= sz
;
321 to
->interim_allocd
+= sz
;
323 if (to
->expires
> from
->expires
) to
->expires
= from
->expires
;
326 void *adns__alloc_final(adns_query qu
, size_t sz
) {
327 /* When we're in the _final stage, we _subtract_ from interim_alloc'd
328 * each allocation, and use final_allocspace to point to the next free
334 rp
= qu
->final_allocspace
;
336 qu
->interim_allocd
-= sz
;
337 assert(qu
->interim_allocd
>=0);
338 qu
->final_allocspace
= (byte
*)rp
+ sz
;
342 static void cancel_children(adns_query qu
) {
343 adns_query cqu
, ncqu
;
345 for (cqu
= qu
->children
.head
; cqu
; cqu
= ncqu
) {
346 ncqu
= cqu
->siblings
.next
;
349 LIST_INIT(qu
->children
);
352 void adns__reset_preserved(adns_query qu
) {
353 assert(!qu
->final_allocspace
);
356 qu
->answer
->rrs
.untyped
= 0;
357 qu
->interim_allocd
= qu
->preserved_allocd
;
360 static void free_query_allocs(adns_query qu
) {
364 for (an
= qu
->allocations
.head
; an
; an
= ann
) { ann
= an
->next
; free(an
); }
365 LIST_INIT(qu
->allocations
);
366 adns__vbuf_free(&qu
->vb
);
369 void adns_cancel(adns_query qu
) {
373 adns__consistency(ads
,qu
,cc_entex
);
375 case query_tosend
: case query_tcpwait
: case query_tcpsent
:
376 LIST_UNLINK(ads
->timew
,qu
);
379 LIST_UNLINK(ads
->childw
,qu
);
382 LIST_UNLINK(ads
->output
,qu
);
387 free_query_allocs(qu
);
390 adns__consistency(ads
,0,cc_entex
);
393 void adns__update_expires(adns_query qu
, unsigned long ttl
, struct timeval now
) {
396 assert(ttl
<= MAXTTLBELIEVE
);
397 max
= now
.tv_sec
+ ttl
;
398 if (qu
->expires
< max
) return;
402 static void makefinal_query(adns_query qu
) {
408 if (qu
->interim_allocd
) {
409 ans
= realloc(qu
->answer
, MEM_ROUND(MEM_ROUND(sizeof(*ans
)) + qu
->interim_allocd
));
410 if (!ans
) goto x_nomem
;
414 qu
->final_allocspace
= (byte
*)ans
+ MEM_ROUND(sizeof(*ans
));
415 adns__makefinal_str(qu
,&ans
->cname
);
416 adns__makefinal_str(qu
,&ans
->owner
);
419 adns__makefinal_block(qu
, &ans
->rrs
.untyped
, ans
->nrrs
*ans
->rrsz
);
421 for (rrn
=0; rrn
<ans
->nrrs
; rrn
++)
422 qu
->typei
->makefinal(qu
, ans
->rrs
.bytes
+ rrn
*ans
->rrsz
);
425 free_query_allocs(qu
);
429 qu
->preserved_allocd
= 0;
430 qu
->answer
->cname
= 0;
431 qu
->answer
->owner
= 0;
432 adns__reset_preserved(qu
); /* (but we just threw away the preserved stuff) */
434 qu
->answer
->status
= adns_s_nomemory
;
435 free_query_allocs(qu
);
438 void adns__query_done(adns_query qu
) {
447 if (qu
->flags
& adns_qf_owner
&& qu
->flags
& adns_qf_search
&&
448 ans
->status
!= adns_s_nomemory
) {
449 if (!save_owner(qu
, qu
->search_vb
.buf
, qu
->search_vb
.used
)) {
450 adns__query_fail(qu
,adns_s_nomemory
);
455 if (ans
->nrrs
&& qu
->typei
->diff_needswap
) {
456 if (!adns__vbuf_ensure(&qu
->vb
,qu
->typei
->rrsz
)) {
457 adns__query_fail(qu
,adns_s_nomemory
);
460 adns__isort(ans
->rrs
.bytes
, ans
->nrrs
, ans
->rrsz
,
462 (int(*)(void*, const void*, const void*))qu
->typei
->diff_needswap
,
466 ans
->expires
= qu
->expires
;
469 LIST_UNLINK_PART(parent
->children
,qu
,siblings
.);
470 LIST_UNLINK(qu
->ads
->childw
,parent
);
471 qu
->ctx
.callback(parent
,qu
);
472 free_query_allocs(qu
);
476 LIST_LINK_TAIL(qu
->ads
->output
,qu
);
478 qu
->state
= query_done
;
481 void adns__query_fail(adns_query qu
, adns_status stat
) {
482 adns__reset_preserved(qu
);
483 qu
->answer
->status
= stat
;
484 adns__query_done(qu
);
487 void adns__makefinal_str(adns_query qu
, char **strp
) {
489 char *before
, *after
;
494 after
= adns__alloc_final(qu
,l
);
495 memcpy(after
,before
,l
);
499 void adns__makefinal_block(adns_query qu
, void **blpp
, size_t sz
) {
500 void *before
, *after
;
504 after
= adns__alloc_final(qu
,sz
);
505 memcpy(after
,before
,sz
);