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; }
45 qu
->state
= query_tosend
;
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
->preserved_allocd
= 0;
52 qu
->final_allocspace
= 0;
57 adns__vbuf_init(&qu
->vb
);
60 qu
->cname_dglen
= qu
->cname_begin
= 0;
62 adns__vbuf_init(&qu
->search_vb
);
63 qu
->search_origlen
= qu
->search_pos
= qu
->search_doneabs
= 0;
69 qu
->udpsent
= qu
->tcpfailed
= 0;
70 timerclear(&qu
->timeout
);
71 qu
->expires
= now
.tv_sec
+ MAXTTLBELIEVE
;
73 memset(&qu
->ctx
,0,sizeof(qu
->ctx
));
75 qu
->answer
->status
= adns_s_ok
;
76 qu
->answer
->cname
= qu
->answer
->owner
= 0;
77 qu
->answer
->type
= typei
->type
;
78 qu
->answer
->expires
= -1;
80 qu
->answer
->rrs
.untyped
= 0;
81 qu
->answer
->rrsz
= typei
->rrsz
;
86 static void query_submit(adns_state ads
, adns_query qu
,
87 const typeinfo
*typei
, vbuf
*qumsg_vb
, int id
,
88 adns_queryflags flags
, struct timeval now
) {
89 /* Fills in the query message in for a previously-allocated query,
90 * and submits it. Cannot fail.
94 adns__vbuf_init(qumsg_vb
);
96 qu
->query_dgram
= malloc(qu
->vb
.used
);
97 if (!qu
->query_dgram
) { adns__query_fail(qu
,adns_s_nomemory
); return; }
100 qu
->query_dglen
= qu
->vb
.used
;
101 memcpy(qu
->query_dgram
,qu
->vb
.buf
,qu
->vb
.used
);
103 adns__query_send(qu
,now
);
104 adns__autosys(ads
,now
);
107 adns_status
adns__internal_submit(adns_state ads
, adns_query
*query_r
,
108 const typeinfo
*typei
, vbuf
*qumsg_vb
, int id
,
109 adns_queryflags flags
, struct timeval now
,
110 const qcontext
*ctx
) {
113 qu
= query_alloc(ads
,typei
,flags
,now
);
114 if (!qu
) { adns__vbuf_free(qumsg_vb
); return adns_s_nomemory
; }
117 memcpy(&qu
->ctx
,ctx
,sizeof(qu
->ctx
));
118 query_submit(ads
,qu
, typei
,qumsg_vb
,id
,flags
,now
);
123 static void query_simple(adns_state ads
, adns_query qu
,
124 const char *owner
, int ol
,
125 const typeinfo
*typei
, adns_queryflags flags
,
126 struct timeval now
) {
131 adns__vbuf_init(&vb
);
133 stat
= adns__mkquery(ads
,&vb
,&id
, owner
,ol
, typei
,flags
);
134 if (stat
) { adns__query_fail(qu
,stat
); return; }
136 query_submit(ads
,qu
, typei
,&vb
,id
, flags
,now
);
139 void adns__search_next(adns_state ads
, adns_query qu
, struct timeval now
) {
140 const char *nextentry
;
143 if (qu
->search_doneabs
<0) {
145 qu
->search_doneabs
= 1;
147 if (qu
->search_pos
>= ads
->nsearchlist
) {
148 if (qu
->search_doneabs
) {
149 stat
= adns_s_nxdomain
; goto x_fail
;
153 qu
->search_doneabs
= 1;
156 nextentry
= ads
->searchlist
[qu
->search_pos
++];
160 qu
->search_vb
.used
= qu
->search_origlen
;
162 if (!adns__vbuf_append(&qu
->search_vb
,".",1) ||
163 !adns__vbuf_appendstr(&qu
->search_vb
,nextentry
)) {
164 stat
= adns_s_nomemory
; goto x_fail
;
168 free(qu
->query_dgram
);
169 qu
->query_dgram
= 0; qu
->query_dglen
= 0;
171 query_simple(ads
,qu
, qu
->search_vb
.buf
, qu
->search_vb
.used
, qu
->typei
, qu
->flags
, now
);
175 adns__query_fail(qu
,stat
);
178 static int save_owner(adns_query qu
, const char *owner
, int ol
) {
179 /* Returns 1 if OK, otherwise there was no memory. */
185 ans
->owner
= adns__alloc_preserved(qu
,ol
+1); if (!ans
->owner
) return 0;
187 memcpy(ans
->owner
,owner
,ol
);
192 int adns_submit(adns_state ads
,
195 adns_queryflags flags
,
197 adns_query
*query_r
) {
200 const typeinfo
*typei
;
205 typei
= adns__findtype(type
);
206 if (!typei
) return ENOSYS
;
208 r
= gettimeofday(&now
,0); if (r
) goto x_errno
;
209 qu
= query_alloc(ads
,typei
,flags
,now
); if (!qu
) goto x_errno
;
211 qu
->ctx
.ext
= context
;
213 memset(&qu
->ctx
.info
,0,sizeof(qu
->ctx
.info
));
218 if (!ol
) { stat
= adns_s_querydomaininvalid
; goto x_adnsfail
; }
219 if (ol
>DNS_MAXDOMAIN
+1) { stat
= adns_s_querydomaintoolong
; goto x_adnsfail
; }
221 if (ol
>=1 && owner
[ol
-1]=='.' && (ol
<2 || owner
[ol
-2]!='\\')) {
222 flags
&= ~adns_qf_search
;
226 if (flags
& adns_qf_search
) {
227 r
= adns__vbuf_append(&qu
->search_vb
,owner
,ol
);
228 if (!r
) { stat
= adns_s_nomemory
; goto x_adnsfail
; }
230 for (ndots
=0, p
=owner
; (p
= strchr(p
,'.')); p
++, ndots
++);
231 qu
->search_doneabs
= (ndots
>= ads
->searchndots
) ?
-1 : 0;
232 qu
->search_origlen
= ol
;
233 adns__search_next(ads
,qu
,now
);
235 if (flags
& adns_qf_owner
) {
236 if (!save_owner(qu
,owner
,ol
)) { stat
= adns_s_nomemory
; goto x_adnsfail
; }
238 query_simple(ads
,qu
, owner
,ol
, typei
,flags
, now
);
243 adns__query_fail(qu
,stat
);
252 int adns_synchronous(adns_state ads
,
255 adns_queryflags flags
,
256 adns_answer
**answer_r
) {
260 r
= adns_submit(ads
,owner
,type
,flags
,0,&qu
);
263 r
= adns_wait(ads
,&qu
,answer_r
,0);
264 if (r
) adns_cancel(qu
);
269 static void *alloc_common(adns_query qu
, size_t sz
) {
272 if (!sz
) return qu
; /* Any old pointer will do */
273 assert(!qu
->final_allocspace
);
274 an
= malloc(MEM_ROUND(MEM_ROUND(sizeof(*an
)) + sz
));
276 LIST_LINK_TAIL(qu
->allocations
,an
);
277 return (byte
*)an
+ MEM_ROUND(sizeof(*an
));
280 void *adns__alloc_interim(adns_query qu
, size_t sz
) {
284 rv
= alloc_common(qu
,sz
);
286 qu
->interim_allocd
+= sz
;
290 void *adns__alloc_preserved(adns_query qu
, size_t sz
) {
294 rv
= adns__alloc_interim(qu
,sz
);
296 qu
->preserved_allocd
+= sz
;
300 void *adns__alloc_mine(adns_query qu
, size_t sz
) {
301 return alloc_common(qu
,MEM_ROUND(sz
));
304 void adns__transfer_interim(adns_query from
, adns_query to
, void *block
, size_t sz
) {
308 an
= (void*)((byte
*)block
- MEM_ROUND(sizeof(*an
)));
310 assert(!to
->final_allocspace
);
311 assert(!from
->final_allocspace
);
313 LIST_UNLINK(from
->allocations
,an
);
314 LIST_LINK_TAIL(to
->allocations
,an
);
316 from
->interim_allocd
-= sz
;
317 to
->interim_allocd
+= sz
;
319 if (to
->expires
> from
->expires
) to
->expires
= from
->expires
;
322 void *adns__alloc_final(adns_query qu
, size_t sz
) {
323 /* When we're in the _final stage, we _subtract_ from interim_alloc'd
324 * each allocation, and use final_allocspace to point to the next free
330 rp
= qu
->final_allocspace
;
332 qu
->interim_allocd
-= sz
;
333 assert(qu
->interim_allocd
>=0);
334 qu
->final_allocspace
= (byte
*)rp
+ sz
;
338 static void cancel_children(adns_query qu
) {
339 adns_query cqu
, ncqu
;
341 for (cqu
= qu
->children
.head
; cqu
; cqu
= ncqu
) {
342 ncqu
= cqu
->siblings
.next
;
345 LIST_INIT(qu
->children
);
348 void adns__reset_preserved(adns_query qu
) {
349 assert(!qu
->final_allocspace
);
352 qu
->answer
->rrs
.untyped
= 0;
353 qu
->interim_allocd
= qu
->preserved_allocd
;
356 static void free_query_allocs(adns_query qu
) {
360 for (an
= qu
->allocations
.head
; an
; an
= ann
) { ann
= an
->next
; free(an
); }
361 adns__vbuf_free(&qu
->vb
);
364 void adns_cancel(adns_query qu
) {
366 case query_tosend
: case query_tcpwait
: case query_tcpsent
:
367 LIST_UNLINK(qu
->ads
->timew
,qu
);
370 LIST_UNLINK(qu
->ads
->childw
,qu
);
373 LIST_UNLINK(qu
->ads
->output
,qu
);
378 free_query_allocs(qu
);
383 void adns__update_expires(adns_query qu
, unsigned long ttl
, struct timeval now
) {
386 assert(ttl
<= MAXTTLBELIEVE
);
387 max
= now
.tv_sec
+ ttl
;
388 if (qu
->expires
< max
) return;
392 static void makefinal_query(adns_query qu
) {
398 if (qu
->interim_allocd
) {
399 ans
= realloc(qu
->answer
, MEM_ROUND(MEM_ROUND(sizeof(*ans
)) + qu
->interim_allocd
));
400 if (!ans
) goto x_nomem
;
404 qu
->final_allocspace
= (byte
*)ans
+ MEM_ROUND(sizeof(*ans
));
405 adns__makefinal_str(qu
,&ans
->cname
);
406 adns__makefinal_str(qu
,&ans
->owner
);
409 adns__makefinal_block(qu
, &ans
->rrs
.untyped
, ans
->nrrs
*ans
->rrsz
);
411 for (rrn
=0; rrn
<ans
->nrrs
; rrn
++)
412 qu
->typei
->makefinal(qu
, ans
->rrs
.bytes
+ rrn
*ans
->rrsz
);
415 free_query_allocs(qu
);
419 qu
->preserved_allocd
= 0;
420 qu
->answer
->cname
= 0;
421 qu
->answer
->owner
= 0;
422 adns__reset_preserved(qu
); /* (but we just threw away the preserved stuff) */
424 qu
->answer
->status
= adns_s_nomemory
;
425 free_query_allocs(qu
);
428 void adns__query_done(adns_query qu
) {
437 if (qu
->flags
& adns_qf_owner
&& qu
->flags
& adns_qf_search
&&
438 ans
->status
!= adns_s_nomemory
) {
439 if (!save_owner(qu
, qu
->search_vb
.buf
, qu
->search_vb
.used
)) {
440 adns__query_fail(qu
,adns_s_nomemory
);
445 if (ans
->nrrs
&& qu
->typei
->diff_needswap
) {
446 if (!adns__vbuf_ensure(&qu
->vb
,qu
->typei
->rrsz
)) {
447 adns__query_fail(qu
,adns_s_nomemory
);
450 adns__isort(ans
->rrs
.bytes
, ans
->nrrs
, ans
->rrsz
,
452 (int(*)(void*, const void*, const void*))qu
->typei
->diff_needswap
,
456 ans
->expires
= qu
->expires
;
459 LIST_UNLINK_PART(parent
->children
,qu
,siblings
.);
460 LIST_UNLINK(qu
->ads
->childw
,parent
);
461 qu
->ctx
.callback(parent
,qu
);
462 free_query_allocs(qu
);
466 LIST_LINK_TAIL(qu
->ads
->output
,qu
);
470 void adns__query_fail(adns_query qu
, adns_status stat
) {
471 adns__reset_preserved(qu
);
472 qu
->answer
->status
= stat
;
473 adns__query_done(qu
);
476 void adns__makefinal_str(adns_query qu
, char **strp
) {
478 char *before
, *after
;
483 after
= adns__alloc_final(qu
,l
);
484 memcpy(after
,before
,l
);
488 void adns__makefinal_block(adns_query qu
, void **blpp
, size_t sz
) {
489 void *before
, *after
;
493 after
= adns__alloc_final(qu
,sz
);
494 memcpy(after
,before
,sz
);