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 int adns__internal_submit(adns_state ads, adns_query *query_r,
37 const typeinfo *typei, vbuf *qumsg_vb, int id,
38 adns_queryflags flags, struct timeval now,
39 adns_status failstat, const qcontext *ctx) {
42 qu= malloc(sizeof(*qu)); if (!qu) goto x_nomemory;
43 qu->answer= malloc(sizeof(*qu->answer)); if (!qu->answer) goto x_freequ_nomemory;
47 qu->back= qu->next= qu->parent= 0;
48 LIST_INIT(qu->children);
49 qu->siblings.next= qu->siblings.back= 0;
50 LIST_INIT(qu->allocations);
51 qu->interim_allocd= 0;
52 qu->final_allocspace= 0;
55 adns__vbuf_init(&qu->vb);
58 qu->cname_dglen= qu->cname_begin= 0;
64 qu->udpsent= qu->tcpfailed= 0;
65 timerclear(&qu->timeout);
66 memcpy(&qu->ctx,ctx,sizeof(qu->ctx));
67 qu->expires= now.tv_sec + MAXTTLBELIEVE;
69 qu->answer->status= adns_s_ok;
71 qu->answer->type= typei->type;
74 qu->answer->rrsz= typei->rrsz;
78 qu->query_dglen= qumsg_vb->used;
80 qu->query_dgram= malloc(qumsg_vb->used);
81 if (!qu->query_dgram) {
82 adns__query_fail(qu,adns_s_nomemory);
85 memcpy(qu->query_dgram,qumsg_vb->buf,qumsg_vb->used);
90 adns__vbuf_init(qumsg_vb);
93 adns__query_fail(qu,failstat);
96 adns__query_udp(qu,now);
97 adns__autosys(ads,now);
104 adns__vbuf_free(qumsg_vb);
105 return adns_s_nomemory;
108 int adns_submit(adns_state ads,
111 adns_queryflags flags,
113 adns_query *query_r) {
118 const typeinfo *typei;
121 typei= adns__findtype(type);
122 if (!typei) return adns_s_unknownrrtype;
126 memset(&ctx.info,0,sizeof(ctx.info));
128 r= gettimeofday(&now,0); if (r) return errno;
131 adns__vbuf_init(&vb);
134 if (ol<=1 || ol>DNS_MAXDOMAIN+1) { stat= adns_s_querydomaintoolong; goto xit; }
136 if (owner[ol-1]=='.' && owner[ol-2]!='\\') { flags &= ~adns_qf_search; ol--; }
138 stat= adns__mkquery(ads,&vb,&id, owner,ol, typei,flags);
141 return adns__internal_submit(ads,query_r, typei,&vb,id, flags,now, stat,&ctx);
144 int adns_synchronous(adns_state ads,
147 adns_queryflags flags,
148 adns_answer **answer_r) {
152 r= adns_submit(ads,owner,type,flags,0,&qu);
155 r= adns_wait(ads,&qu,answer_r,0);
156 if (r) adns_cancel(qu);
161 static void *alloc_common(adns_query qu, size_t sz) {
164 if (!sz) return qu; /* Any old pointer will do */
165 assert(!qu->final_allocspace);
166 an= malloc(MEM_ROUND(MEM_ROUND(sizeof(*an)) + sz));
168 LIST_LINK_TAIL(qu->allocations,an);
169 return (byte*)an + MEM_ROUND(sizeof(*an));
172 void *adns__alloc_interim(adns_query qu, size_t sz) {
174 qu->interim_allocd += sz;
175 return alloc_common(qu,sz);
178 void *adns__alloc_mine(adns_query qu, size_t sz) {
179 return alloc_common(qu,MEM_ROUND(sz));
182 void adns__transfer_interim(adns_query from, adns_query to, void *block, size_t sz) {
186 an= (void*)((byte*)block - MEM_ROUND(sizeof(*an)));
188 assert(!to->final_allocspace);
189 assert(!from->final_allocspace);
191 LIST_UNLINK(from->allocations,an);
192 LIST_LINK_TAIL(to->allocations,an);
194 from->interim_allocd -= sz;
195 to->interim_allocd += sz;
197 if (to->expires > from->expires) to->expires= from->expires;
200 void *adns__alloc_final(adns_query qu, size_t sz) {
201 /* When we're in the _final stage, we _subtract_ from interim_alloc'd
202 * each allocation, and use final_allocspace to point to the next free
208 rp= qu->final_allocspace;
210 qu->interim_allocd -= sz;
211 assert(qu->interim_allocd>=0);
212 qu->final_allocspace= (byte*)rp + sz;
216 static void cancel_children(adns_query qu) {
217 adns_query cqu, ncqu;
219 for (cqu= qu->children.head; cqu; cqu= ncqu) {
220 ncqu= cqu->siblings.next;
223 LIST_INIT(qu->children);
226 void adns__reset_cnameonly(adns_query qu) {
227 assert(!qu->final_allocspace);
231 qu->interim_allocd= qu->answer->cname ? MEM_ROUND(strlen(qu->answer->cname)+1) : 0;
234 static void free_query_allocs(adns_query qu) {
238 for (an= qu->allocations.head; an; an= ann) { ann= an->next; free(an); }
239 adns__vbuf_free(&qu->vb);
242 void adns_cancel(adns_query qu) {
244 case query_udp: case query_tcpwait: case query_tcpsent:
245 LIST_UNLINK(qu->ads->timew,qu);
248 LIST_UNLINK(qu->ads->childw,qu);
251 LIST_UNLINK(qu->ads->output,qu);
256 free_query_allocs(qu);
261 void adns__update_expires(adns_query qu, unsigned long ttl, struct timeval now) {
264 assert(ttl <= MAXTTLBELIEVE);
265 max= now.tv_sec + ttl;
266 if (qu->expires < max) return;
270 static void makefinal_query(adns_query qu) {
276 if (qu->interim_allocd) {
277 ans= realloc(qu->answer, MEM_ROUND(MEM_ROUND(sizeof(*ans)) + qu->interim_allocd));
278 if (!ans) goto x_nomem;
282 qu->final_allocspace= (byte*)ans + MEM_ROUND(sizeof(*ans));
283 adns__makefinal_str(qu,&ans->cname);
286 adns__makefinal_block(qu, &ans->rrs.untyped, ans->nrrs*ans->rrsz);
288 for (rrn=0; rrn<ans->nrrs; rrn++)
289 qu->typei->makefinal(qu, ans->rrs.bytes + rrn*ans->rrsz);
292 free_query_allocs(qu);
296 qu->answer->status= adns_s_nomemory;
297 qu->answer->cname= 0;
298 adns__reset_cnameonly(qu);
299 free_query_allocs(qu);
302 void adns__query_done(adns_query qu) {
309 if (ans->nrrs && qu->typei->diff_needswap) {
310 if (!adns__vbuf_ensure(&qu->vb,qu->typei->rrsz)) {
311 adns__query_fail(qu,adns_s_nomemory);
314 adns__isort(ans->rrs.bytes, ans->nrrs, ans->rrsz,
316 (int(*)(void*, const void*, const void*))qu->typei->diff_needswap,
320 ans->expires= qu->expires;
323 LIST_UNLINK_PART(parent->children,qu,siblings.);
324 qu->ctx.callback(parent,qu);
325 free_query_allocs(qu);
329 LIST_LINK_TAIL(qu->ads->output,qu);
333 void adns__query_fail(adns_query qu, adns_status stat) {
334 adns__reset_cnameonly(qu);
335 qu->answer->status= stat;
336 adns__query_done(qu);
339 void adns__makefinal_str(adns_query qu, char **strp) {
341 char *before, *after;
346 after= adns__alloc_final(qu,l);
347 memcpy(after,before,l);
351 void adns__makefinal_block(adns_query qu, void **blpp, size_t sz) {
352 void *before, *after;
356 after= adns__alloc_final(qu,sz);
357 memcpy(after,before,sz);