3 * - overall query management (allocation, completion)
4 * - per-query memory management
5 * - query submission and cancellation (user-visible and internal)
9 * Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk>
11 * It is part of adns, which is
12 * Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk>
13 * Copyright (C) 1999 Tony Finch <dot@dotat.at>
15 * This program is free software; you can redistribute it and/or modify
16 * it under the terms of the GNU General Public License as published by
17 * the Free Software Foundation; either version 2, or (at your option)
20 * This program is distributed in the hope that it will be useful,
21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23 * GNU General Public License for more details.
25 * You should have received a copy of the GNU General Public License
26 * along with this program; if not, write to the Free Software Foundation,
27 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
40 static adns_query query_alloc(adns_state ads, const typeinfo *typei,
41 adns_queryflags flags, struct timeval now) {
42 /* Allocate a virgin query and return it. */
45 qu= malloc(sizeof(*qu)); if (!qu) return 0;
46 qu->answer= malloc(sizeof(*qu->answer)); if (!qu->answer) { free(qu); return 0; }
49 qu->state= query_tosend;
50 qu->back= qu->next= qu->parent= 0;
51 LIST_INIT(qu->children);
52 LINK_INIT(qu->siblings);
53 LIST_INIT(qu->allocations);
54 qu->interim_allocd= 0;
55 qu->preserved_allocd= 0;
56 qu->final_allocspace= 0;
61 adns__vbuf_init(&qu->vb);
64 qu->cname_dglen= qu->cname_begin= 0;
66 adns__vbuf_init(&qu->search_vb);
67 qu->search_origlen= qu->search_pos= qu->search_doneabs= 0;
73 qu->udpsent= qu->tcpfailed= 0;
74 timerclear(&qu->timeout);
75 qu->expires= now.tv_sec + MAXTTLBELIEVE;
77 memset(&qu->ctx,0,sizeof(qu->ctx));
79 qu->answer->status= adns_s_ok;
80 qu->answer->cname= qu->answer->owner= 0;
81 qu->answer->type= typei->type;
82 qu->answer->expires= -1;
84 qu->answer->rrs.untyped= 0;
85 qu->answer->rrsz= typei->rrsz;
90 static void query_submit(adns_state ads, adns_query qu,
91 const typeinfo *typei, vbuf *qumsg_vb, int id,
92 adns_queryflags flags, struct timeval now) {
93 /* Fills in the query message in for a previously-allocated query,
94 * and submits it. Cannot fail.
98 adns__vbuf_init(qumsg_vb);
100 qu->query_dgram= malloc(qu->vb.used);
101 if (!qu->query_dgram) { adns__query_fail(qu,adns_s_nomemory); return; }
104 qu->query_dglen= qu->vb.used;
105 memcpy(qu->query_dgram,qu->vb.buf,qu->vb.used);
107 adns__query_send(qu,now);
110 adns_status adns__internal_submit(adns_state ads, adns_query *query_r,
111 const typeinfo *typei, vbuf *qumsg_vb, int id,
112 adns_queryflags flags, struct timeval now,
113 const qcontext *ctx) {
116 qu= query_alloc(ads,typei,flags,now);
117 if (!qu) { adns__vbuf_free(qumsg_vb); return adns_s_nomemory; }
120 memcpy(&qu->ctx,ctx,sizeof(qu->ctx));
121 query_submit(ads,qu, typei,qumsg_vb,id,flags,now);
126 static void query_simple(adns_state ads, adns_query qu,
127 const char *owner, int ol,
128 const typeinfo *typei, adns_queryflags flags,
129 struct timeval now) {
134 adns__vbuf_init(&vb);
136 stat= adns__mkquery(ads,&vb,&id, owner,ol, typei,flags);
137 if (stat) { adns__query_fail(qu,stat); return; }
139 query_submit(ads,qu, typei,&vb,id, flags,now);
142 void adns__search_next(adns_state ads, adns_query qu, struct timeval now) {
143 const char *nextentry;
146 if (qu->search_doneabs<0) {
148 qu->search_doneabs= 1;
150 if (qu->search_pos >= ads->nsearchlist) {
151 if (qu->search_doneabs) {
152 stat= adns_s_nxdomain; goto x_fail;
156 qu->search_doneabs= 1;
159 nextentry= ads->searchlist[qu->search_pos++];
163 qu->search_vb.used= qu->search_origlen;
165 if (!adns__vbuf_append(&qu->search_vb,".",1) ||
166 !adns__vbuf_appendstr(&qu->search_vb,nextentry)) {
167 stat= adns_s_nomemory; goto x_fail;
171 free(qu->query_dgram);
172 qu->query_dgram= 0; qu->query_dglen= 0;
174 query_simple(ads,qu, qu->search_vb.buf, qu->search_vb.used, qu->typei, qu->flags, now);
178 adns__query_fail(qu,stat);
181 static int save_owner(adns_query qu, const char *owner, int ol) {
182 /* Returns 1 if OK, otherwise there was no memory. */
188 ans->owner= adns__alloc_preserved(qu,ol+1); if (!ans->owner) return 0;
190 memcpy(ans->owner,owner,ol);
195 int adns_submit(adns_state ads,
198 adns_queryflags flags,
200 adns_query *query_r) {
203 const typeinfo *typei;
208 adns__consistency(ads,0,cc_entex);
210 typei= adns__findtype(type);
211 if (!typei) return ENOSYS;
213 r= gettimeofday(&now,0); if (r) goto x_errno;
214 qu= query_alloc(ads,typei,flags,now); if (!qu) goto x_errno;
216 qu->ctx.ext= context;
218 memset(&qu->ctx.info,0,sizeof(qu->ctx.info));
223 if (!ol) { stat= adns_s_querydomaininvalid; goto x_adnsfail; }
224 if (ol>DNS_MAXDOMAIN+1) { stat= adns_s_querydomaintoolong; goto x_adnsfail; }
226 if (ol>=1 && owner[ol-1]=='.' && (ol<2 || owner[ol-2]!='\\')) {
227 flags &= ~adns_qf_search;
231 if (flags & adns_qf_search) {
232 r= adns__vbuf_append(&qu->search_vb,owner,ol);
233 if (!r) { stat= adns_s_nomemory; goto x_adnsfail; }
235 for (ndots=0, p=owner; (p= strchr(p,'.')); p++, ndots++);
236 qu->search_doneabs= (ndots >= ads->searchndots) ? -1 : 0;
237 qu->search_origlen= ol;
238 adns__search_next(ads,qu,now);
240 if (flags & adns_qf_owner) {
241 if (!save_owner(qu,owner,ol)) { stat= adns_s_nomemory; goto x_adnsfail; }
243 query_simple(ads,qu, owner,ol, typei,flags, now);
245 adns__autosys(ads,now);
246 adns__consistency(ads,qu,cc_entex);
250 adns__query_fail(qu,stat);
251 adns__consistency(ads,qu,cc_entex);
257 adns__consistency(ads,0,cc_entex);
261 int adns_synchronous(adns_state ads,
264 adns_queryflags flags,
265 adns_answer **answer_r) {
269 r= adns_submit(ads,owner,type,flags,0,&qu);
272 r= adns_wait(ads,&qu,answer_r,0);
273 if (r) adns_cancel(qu);
278 static void *alloc_common(adns_query qu, size_t sz) {
281 if (!sz) return qu; /* Any old pointer will do */
282 assert(!qu->final_allocspace);
283 an= malloc(MEM_ROUND(MEM_ROUND(sizeof(*an)) + sz));
285 LIST_LINK_TAIL(qu->allocations,an);
286 return (byte*)an + MEM_ROUND(sizeof(*an));
289 void *adns__alloc_interim(adns_query qu, size_t sz) {
293 rv= alloc_common(qu,sz);
295 qu->interim_allocd += sz;
299 void *adns__alloc_preserved(adns_query qu, size_t sz) {
303 rv= adns__alloc_interim(qu,sz);
305 qu->preserved_allocd += sz;
309 void *adns__alloc_mine(adns_query qu, size_t sz) {
310 return alloc_common(qu,MEM_ROUND(sz));
313 void adns__transfer_interim(adns_query from, adns_query to, void *block, size_t sz) {
317 an= (void*)((byte*)block - MEM_ROUND(sizeof(*an)));
319 assert(!to->final_allocspace);
320 assert(!from->final_allocspace);
322 LIST_UNLINK(from->allocations,an);
323 LIST_LINK_TAIL(to->allocations,an);
325 from->interim_allocd -= sz;
326 to->interim_allocd += sz;
328 if (to->expires > from->expires) to->expires= from->expires;
331 void *adns__alloc_final(adns_query qu, size_t sz) {
332 /* When we're in the _final stage, we _subtract_ from interim_alloc'd
333 * each allocation, and use final_allocspace to point to the next free
339 rp= qu->final_allocspace;
341 qu->interim_allocd -= sz;
342 assert(qu->interim_allocd>=0);
343 qu->final_allocspace= (byte*)rp + sz;
347 static void cancel_children(adns_query qu) {
348 adns_query cqu, ncqu;
350 for (cqu= qu->children.head; cqu; cqu= ncqu) {
351 ncqu= cqu->siblings.next;
356 void adns__reset_preserved(adns_query qu) {
357 assert(!qu->final_allocspace);
360 qu->answer->rrs.untyped= 0;
361 qu->interim_allocd= qu->preserved_allocd;
364 static void free_query_allocs(adns_query qu) {
368 for (an= qu->allocations.head; an; an= ann) { ann= an->next; free(an); }
369 LIST_INIT(qu->allocations);
370 adns__vbuf_free(&qu->vb);
373 void adns_cancel(adns_query qu) {
377 adns__consistency(ads,qu,cc_entex);
378 if (qu->parent) LIST_UNLINK_PART(qu->parent->children,qu,siblings.);
380 case query_tosend: case query_tcpwait: case query_tcpsent:
381 LIST_UNLINK(ads->timew,qu);
384 LIST_UNLINK(ads->childw,qu);
387 LIST_UNLINK(ads->output,qu);
392 free_query_allocs(qu);
395 adns__consistency(ads,0,cc_entex);
398 void adns__update_expires(adns_query qu, unsigned long ttl, struct timeval now) {
401 assert(ttl <= MAXTTLBELIEVE);
402 max= now.tv_sec + ttl;
403 if (qu->expires < max) return;
407 static void makefinal_query(adns_query qu) {
413 if (qu->interim_allocd) {
414 ans= realloc(qu->answer, MEM_ROUND(MEM_ROUND(sizeof(*ans)) + qu->interim_allocd));
415 if (!ans) goto x_nomem;
419 qu->final_allocspace= (byte*)ans + MEM_ROUND(sizeof(*ans));
420 adns__makefinal_str(qu,&ans->cname);
421 adns__makefinal_str(qu,&ans->owner);
424 adns__makefinal_block(qu, &ans->rrs.untyped, ans->nrrs*ans->rrsz);
426 for (rrn=0; rrn<ans->nrrs; rrn++)
427 qu->typei->makefinal(qu, ans->rrs.bytes + rrn*ans->rrsz);
430 free_query_allocs(qu);
434 qu->preserved_allocd= 0;
435 qu->answer->cname= 0;
436 qu->answer->owner= 0;
437 adns__reset_preserved(qu); /* (but we just threw away the preserved stuff) */
439 qu->answer->status= adns_s_nomemory;
440 free_query_allocs(qu);
443 void adns__query_done(adns_query qu) {
452 if (qu->flags & adns_qf_owner && qu->flags & adns_qf_search &&
453 ans->status != adns_s_nomemory) {
454 if (!save_owner(qu, qu->search_vb.buf, qu->search_vb.used)) {
455 adns__query_fail(qu,adns_s_nomemory);
460 if (ans->nrrs && qu->typei->diff_needswap) {
461 if (!adns__vbuf_ensure(&qu->vb,qu->typei->rrsz)) {
462 adns__query_fail(qu,adns_s_nomemory);
465 adns__isort(ans->rrs.bytes, ans->nrrs, ans->rrsz,
467 (int(*)(void*, const void*, const void*))qu->typei->diff_needswap,
471 ans->expires= qu->expires;
474 LIST_UNLINK_PART(parent->children,qu,siblings.);
475 LIST_UNLINK(qu->ads->childw,parent);
476 qu->ctx.callback(parent,qu);
477 free_query_allocs(qu);
481 LIST_LINK_TAIL(qu->ads->output,qu);
482 qu->state= query_done;
486 void adns__query_fail(adns_query qu, adns_status stat) {
487 adns__reset_preserved(qu);
488 qu->answer->status= stat;
489 adns__query_done(qu);
492 void adns__makefinal_str(adns_query qu, char **strp) {
494 char *before, *after;
499 after= adns__alloc_final(qu,l);
500 memcpy(after,before,l);
504 void adns__makefinal_block(adns_query qu, void **blpp, size_t sz) {
505 void *before, *after;
509 after= adns__alloc_final(qu,sz);
510 memcpy(after,before,sz);