3 * - declarations of private objects with external linkage (adns__*)
4 * - definitons of internal macros
5 * - comments regarding library data structures
8 * This file is part of adns, which is
9 * Copyright (C) 1997-2000,2003,2006 Ian Jackson
10 * Copyright (C) 1999-2000,2003,2006 Tony Finch
11 * Copyright (C) 1991 Massachusetts Institute of Technology
12 * (See the file INSTALL for full details.)
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2, or (at your option)
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with this program; if not, write to the Free Software Foundation,
26 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
29 #ifndef ADNS_INTERNAL_H_INCLUDED
30 #define ADNS_INTERNAL_H_INCLUDED
33 typedef unsigned char byte;
45 #define ADNS_FEATURE_MANYAF
49 #ifdef ADNS_REGRESS_TEST
50 # include "hredirect.h"
53 /* Configuration and constants */
56 #define MAXSORTLIST 15
57 #define UDPMAXRETRIES 15
58 #define UDPRETRYMS 2000
59 #define TCPWAITMS 30000
60 #define TCPCONNMS 14000
61 #define TCPIDLEMS 30000
62 #define MAXTTLBELIEVE (7*86400) /* any TTL > 7 days is capped */
65 #define DNS_MAXUDP 512
66 #define DNS_MAXLABEL 63
67 #define DNS_MAXDOMAIN 255
68 #define DNS_HDRSIZE 12
69 #define DNS_IDOFFSET 0
70 #define DNS_CLASS_IN 1
72 #define DNS_INADDR_ARPA "in-addr", "arpa"
73 #define DNS_IP6_ARPA "ip6", "arpa"
75 #define MAX_ADDRSTRLEN 64
77 #define STRINGIFY(x) REALLY_STRINGIFY(x)
78 #define REALLY_STRINGIFY(x) #x
80 #define MAX_POLLFDS ADNS_POLLFDS_RECOMMENDED
98 adns__qf_addr_answer= 0x01000000,/* addr query received an answer */
99 adns__qf_addr_cname = 0x02000000 /* addr subquery performed on cname */
102 /* Shared data structures */
123 int dglen, nsstart, nscount, arcount;
132 union checklabel_state {
143 const void *(*sockaddr_to_inaddr)(const struct sockaddr *sa);
144 int (*sockaddr_equalp)(const struct sockaddr *sa,
145 const struct sockaddr *sb);
146 void (*prefix_mask)(int len, union gen_addr *a);
147 int (*guess_len)(const union gen_addr *a);
148 int (*matchp)(const union gen_addr *addr,
149 const union gen_addr *base, const union gen_addr *mask);
150 int (*rev_parsecomp)(const char *p, size_t n);
151 void (*rev_mkaddr)(union gen_addr *addr, const byte *ipv);
152 char *(*rev_mkname)(const struct sockaddr *sa, char *buf);
155 struct afinfo_addr { const afinfo *ai; union gen_addr addr; };
159 void (*callback)(adns_query parent, adns_query child);
162 struct afinfo_addr ptr_parent_addr;
163 adns_rr_hostaddr *hostaddr;
164 } pinfo; /* state for use by parent's callback function */
170 } tinfo; /* type-specific state for the query itself: zero-init if you
171 * don't know better. */
175 typedef struct typeinfo {
181 void (*makefinal)(adns_query qu, void *data);
182 /* Change memory management of *data.
183 * Previously, used alloc_interim, now use alloc_final.
186 adns_status (*convstring)(vbuf *vb, const void *data);
187 /* Converts the RR data to a string representation in vbuf.
188 * vbuf will be appended to (it must have been initialised),
189 * and will not be null-terminated by convstring.
192 adns_status (*parse)(const parseinfo *pai, int cbyte,
193 int max, void *store_r);
194 /* Parse one RR, in dgram of length dglen, starting at cbyte and
195 * extending until at most max.
197 * The RR should be stored at *store_r, of length qu->typei->rrsz.
199 * If there is an overrun which might indicate truncation, it should set
200 * *rdstart to -1; otherwise it may set it to anything else positive.
202 * nsstart is the offset of the authority section.
205 int (*diff_needswap)(adns_state ads,const void *datap_a,const void *datap_b);
206 /* Returns !0 if RR a should be strictly after RR b in the sort order,
207 * 0 otherwise. Must not fail.
210 adns_status (*checklabel)(adns_state ads, adns_queryflags flags,
211 union checklabel_state *css, qcontext *ctx,
212 int labnum, const char *label, int lablen);
213 /* Check a label from the query domain string. The label is not
214 * necessarily null-terminated. The query has not yet been constructed,
215 * and this hook can refuse its submission by returning a nonzero status.
216 * State can be stored in *css between calls, and useful information can be
217 * stashed in ctx->tinfo, to be stored with the query (e.g., it will be
218 * available to the parse hook). This hook can detect a first call because
219 * labnum is zero, and a final call because lablen is zero.
222 void (*postsort)(adns_state ads, void *array, int nrrs,
223 const struct typeinfo *typei);
224 /* Called immediately after the RRs have been sorted, and may rearrange
225 * them. (This is really for the benefit of SRV's bizarre weighting
226 * stuff.) May be 0 to mean nothing needs to be done.
229 int (*getrrsz)(adns_rrtype type);
230 /* Return the output resource-record element size; if this is null, then
231 * the rrsz member can be used.
234 void (*query_send)(adns_query qu, struct timeval now);
235 /* Send the query to nameservers, and hook it into the appropriate queue.
236 * Normal behaviour is to call adns__query_send, but this can be overridden
237 * for special effects.
241 adns_status adns__ckl_hostname(adns_state ads, adns_queryflags flags,
242 union checklabel_state *css,
243 qcontext *ctx, int labnum,
244 const char *label, int lablen);
245 /* implemented in query.c, used by types.c as default
246 * and as part of implementation for some fancier types */
248 typedef struct allocnode {
249 struct allocnode *next, *back;
264 enum { query_tosend, query_tcpw, query_childw, query_done } state;
265 adns_query back, next, parent;
266 struct { adns_query head, tail; } children;
267 struct { adns_query back, next; } siblings;
268 struct { allocnode *head, *tail; } allocations;
269 int interim_allocd, preserved_allocd;
270 void *final_allocspace;
272 const typeinfo *typei;
277 /* General-purpose messing-about buffer.
278 * Wherever a `big' interface is crossed, this may be corrupted/changed
279 * unless otherwise specified.
283 /* This is allocated when a query is submitted, to avoid being unable
284 * to relate errors to queries if we run out of memory. During
285 * query processing status, rrs is 0. cname is set if
286 * we found a cname (this corresponds to cname_dgram in the query
287 * structure). type is set from the word go. nrrs and rrs
288 * are set together, when we find how many rrs there are.
289 * owner is set during querying unless we're doing searchlist,
290 * in which case it is set only when we find an answer.
294 int cname_dglen, cname_begin;
295 /* If non-0, has been allocated using . */
298 int search_origlen, search_pos, search_doneabs;
299 /* Used by the searching algorithm. The query domain in textual form
300 * is copied into the vbuf, and _origlen set to its length. Then
301 * we walk the searchlist, if we want to. _pos says where we are
302 * (next entry to try), and _doneabs says whether we've done the
303 * absolute query yet (0=not yet, 1=done, -1=must do straight away,
304 * but not done yet). If flags doesn't have adns_qf_search then
305 * the vbuf is initialised but empty and everything else is zero.
308 int id, flags, retries;
310 unsigned long udpsent; /* bitmap indexed by server */
311 struct timeval timeout;
312 time_t expires; /* Earliest expiry time of any record we used. */
318 * state Queue child id nextudpserver udpsent tcpfailed
320 * tosend NONE null >=0 0 zero zero
321 * tosend udpw null >=0 any nonzero zero
322 * tosend NONE null >=0 any nonzero zero
324 * tcpw tcpw null >=0 irrelevant any any
326 * child childw set >=0 irrelevant irrelevant irrelevant
327 * child NONE null >=0 irrelevant irrelevant irrelevant
328 * done output null -1 irrelevant irrelevant irrelevant
330 * Queries are only not on a queue when they are actually being processed.
331 * Queries in state tcpw/tcpw have been sent (or are in the to-send buffer)
332 * iff the tcp connection is in state server_ok.
334 * +------------------------+
335 * START -----> | tosend/NONE |
336 * +------------------------+
338 * too big for UDP / UDP timeout \ \ send via UDP
339 * send via TCP / more retries \ \
340 * when conn'd / desired \ \
343 * +-----------+ +-------------+
344 * | tcpw/tcpw | ________ | tosend/udpw |
345 * +-----------+ \ +-------------+
346 * | | | UDP timeout | |
349 * \ | TCP died | desired | |
351 * \ \ servers | TCP / |
352 * \ \ to try | timeout / |
354 * reply \ _| +------------------+ / reply
355 * \ | done/output FAIL | /
356 * \ +------------------+ /
359 * (..... got reply ....)
361 * need child query/ies / \ no child query
364 * +---------------+ +----------------+
365 * | childw/childw | ----------------> | done/output OK |
366 * +---------------+ children done +----------------+
370 struct query_queue { adns_query head, tail; };
375 adns_initflags iflags;
376 adns_logcallbackfn *logfn;
379 struct query_queue udpw, tcpw, childw, output;
380 adns_query forallnext;
381 int nextid, tcpsocket;
382 struct udpsocket { const afinfo *ai; int fd; } udpsocket[MAXUDP];
384 vbuf tcpsend, tcprecv;
385 int nservers, nsortlist, nsearchlist, searchndots, tcpserver, tcprecv_skip;
386 enum adns__tcpstate {
387 server_disconnected, server_connecting,
388 server_ok, server_broken
390 struct timeval tcptimeout;
391 /* This will have tv_sec==0 if it is not valid. It will always be
392 * valid if tcpstate _connecting. When _ok, it will be nonzero if
393 * we are idle (ie, tcpw queue is empty), in which case it is the
394 * absolute time when we will close the connection.
396 struct sigaction stdsigpipe;
398 struct pollfd pollfds_buf[MAX_POLLFDS];
399 adns_rr_addr servers[MAXSERVERS];
402 union gen_addr base, mask;
403 } sortlist[MAXSORTLIST];
405 unsigned short rand48xsubi[3];
408 /* From addrfam.c: */
410 extern const afinfo adns__inet_afinfo, adns__inet6_afinfo;
414 int adns__setnonblock(adns_state ads, int fd); /* => errno value */
416 /* From general.c: */
418 const char *adns__sockaddr_ntoa(struct sockaddr *sa, size_t n, char *buf);
419 /* Buffer must be at least MAX_ADDRSTRLEN bytes long. */
421 void adns__vlprintf(adns_state ads, const char *fmt, va_list al);
422 void adns__lprintf(adns_state ads, const char *fmt,
423 ...) PRINTFFORMAT(2,3);
425 void adns__vdiag(adns_state ads, const char *pfx, adns_initflags prevent,
426 int serv, adns_query qu, const char *fmt, va_list al);
428 void adns__debug(adns_state ads, int serv, adns_query qu,
429 const char *fmt, ...) PRINTFFORMAT(4,5);
430 void adns__warn(adns_state ads, int serv, adns_query qu,
431 const char *fmt, ...) PRINTFFORMAT(4,5);
432 void adns__diag(adns_state ads, int serv, adns_query qu,
433 const char *fmt, ...) PRINTFFORMAT(4,5);
435 int adns__vbuf_ensure(vbuf *vb, int want);
436 int adns__vbuf_appendstr(vbuf *vb, const char *data); /* doesn't include nul */
437 int adns__vbuf_append(vbuf *vb, const byte *data, int len);
438 /* 1=>success, 0=>realloc failed */
439 void adns__vbuf_appendq(vbuf *vb, const byte *data, int len);
440 void adns__vbuf_init(vbuf *vb);
441 void adns__vbuf_free(vbuf *vb);
443 const char *adns__diag_domain(adns_state ads, int serv, adns_query qu,
445 const byte *dgram, int dglen, int cbyte);
446 /* Unpicks a domain in a datagram and returns a string suitable for
447 * printing it as. Never fails - if an error occurs, it will
448 * return some kind of string describing the error.
450 * serv may be -1 and qu may be 0. vb must have been initialised,
451 * and will be left in an arbitrary consistent state.
453 * Returns either vb->buf, or a pointer to a string literal. Do not modify
454 * vb before using the return value.
457 void adns__isort(void *array, int nobjs, int sz, void *tempbuf,
458 int (*needswap)(void *context, const void *a, const void *b),
460 /* Does an insertion sort of array which must contain nobjs objects
461 * each sz bytes long. tempbuf must point to a buffer at least
462 * sz bytes long. needswap should return !0 if a>b (strictly, ie
463 * wrong order) 0 if a<=b (ie, order is fine).
466 void adns__sigpipe_protect(adns_state);
467 void adns__sigpipe_unprotect(adns_state);
468 /* If SIGPIPE protection is not disabled, will block all signals except
469 * SIGPIPE, and set SIGPIPE's disposition to SIG_IGN. (And then restore.)
470 * Each call to _protect must be followed by a call to _unprotect before
471 * any significant amount of code gets to run, since the old signal mask
472 * is stored in the adns structure.
475 /* From transmit.c: */
477 adns_status adns__mkquery(adns_state ads, vbuf *vb, int *id_r,
478 const char *owner, int ol,
479 const typeinfo *typei, adns_rrtype type,
480 adns_queryflags flags);
481 /* Assembles a query packet in vb. A new id is allocated and returned.
484 adns_status adns__mkquery_frdgram(adns_state ads, vbuf *vb, int *id_r,
485 const byte *qd_dgram, int qd_dglen,
487 adns_rrtype type, adns_queryflags flags);
488 /* Same as adns__mkquery, but takes the owner domain from an existing datagram.
489 * That domain must be correct and untruncated.
492 void adns__querysend_tcp(adns_query qu, struct timeval now);
493 /* Query must be in state tcpw/tcpw; it will be sent if possible and
494 * no further processing can be done on it for now. The connection
495 * might be broken, but no reconnect will be attempted.
498 void adns__query_send(adns_query qu, struct timeval now);
499 /* Query must be in state tosend/NONE; it will be moved to a new state,
500 * and no further processing can be done on it for now.
501 * (Resulting state is one of udp/timew, tcpwait/timew (if server not
502 * connected), tcpsent/timew, child/childw or done/output.)
503 * __query_send may decide to use either UDP or TCP depending whether
504 * _qf_usevc is set (or has become set) and whether the query is too
510 adns_status adns__internal_submit(adns_state ads, adns_query *query_r,
511 const typeinfo *typei, adns_rrtype,
512 vbuf *qumsg_vb, int id,
513 adns_queryflags flags, struct timeval now,
515 /* Submits a query (for internal use, called during external submits).
517 * The new query is returned in *query_r, or we return adns_s_nomemory.
519 * The query datagram should already have been assembled in qumsg_vb;
520 * the memory for it is _taken over_ by this routine whether it
521 * succeeds or fails (if it succeeds, the vbuf is reused for qu->vb).
523 * If adns__qf_nosend is set in flags, then the query is not sent: doing
524 * whatever is necessary to send the query and link it onto the appropriate
525 * queue is left as the caller's responsibility.
527 * *ctx is copied byte-for-byte into the query.
529 * When the child query is done, ctx->callback will be called. The
530 * child will already have been taken off both the global list of
531 * queries in ads and the list of children in the parent. The child
532 * will be freed when the callback returns. The parent will have been
533 * taken off the global childw queue.
535 * The callback should either call adns__query_done, if it is
536 * complete, or adns__query_fail, if an error has occurred, in which
537 * case the other children (if any) will be cancelled. If the parent
538 * has more unfinished children (or has just submitted more) then the
539 * callback may choose to wait for them - it must then put the parent
540 * back on the childw queue.
543 void adns__search_next(adns_state ads, adns_query qu, struct timeval now);
544 /* Walks down the searchlist for a query with adns_qf_search.
545 * The query should have just had a negative response, or not had
546 * any queries sent yet, and should not be on any queue.
547 * The query_dgram if any will be freed and forgotten and a new
548 * one constructed from the search_* members of the query.
550 * Cannot fail (in case of error, calls adns__query_fail).
553 void *adns__alloc_interim(adns_query qu, size_t sz);
554 void *adns__alloc_preserved(adns_query qu, size_t sz);
555 /* Allocates some memory, and records which query it came from
556 * and how much there was.
558 * If an error occurs in the query, all the memory from _interim is
559 * simply freed. If the query succeeds, one large buffer will be made
560 * which is big enough for all these allocations, and then
561 * adns__alloc_final will get memory from this buffer.
563 * _alloc_interim can fail (and return 0).
564 * The caller must ensure that the query is failed.
566 * The memory from _preserved is is kept and transferred into the
567 * larger buffer - unless we run out of memory, in which case it too
568 * is freed. When you use _preserved you have to add code to the
569 * x_nomem error exit case in adns__makefinal_query to clear out the
570 * pointers you made to those allocations, because that's when they're
571 * thrown away; you should also make a note in the declaration of
572 * those pointer variables, to note that they are _preserved rather
573 * than _interim. If they're in the answer, note it here:
574 * answer->cname and answer->owner are _preserved.
577 void adns__transfer_interim(adns_query from, adns_query to, void *block);
578 /* Transfers an interim allocation from one query to another, so that
579 * the `to' query will have room for the data when we get to makefinal
580 * and so that the free will happen when the `to' query is freed
581 * rather than the `from' query.
583 * It is legal to call adns__transfer_interim with a null pointer; this
586 * _transfer_interim also ensures that the expiry time of the `to' query
587 * is no later than that of the `from' query, so that child queries'
588 * TTLs get inherited by their parents.
591 void adns__free_interim(adns_query qu, void *p);
592 /* Forget about a block allocated by adns__alloc_interim.
595 void *adns__alloc_mine(adns_query qu, size_t sz);
596 /* Like _interim, but does not record the length for later
597 * copying into the answer. This just ensures that the memory
598 * will be freed when we're done with the query.
601 void *adns__alloc_final(adns_query qu, size_t sz);
602 /* Cannot fail, and cannot return 0.
605 void adns__makefinal_block(adns_query qu, void **blpp, size_t sz);
606 void adns__makefinal_str(adns_query qu, char **strp);
608 void adns__reset_preserved(adns_query qu);
609 /* Resets all of the memory management stuff etc. to take account of
610 * only the _preserved stuff from _alloc_preserved. Used when we find
611 * an error somewhere and want to just report the error (with perhaps
612 * CNAME, owner, etc. info), and also when we're halfway through RRs
613 * in a datagram and discover that we need to retry the query.
616 void adns__query_done(adns_query qu);
617 void adns__query_fail(adns_query qu, adns_status stat);
618 void adns__cancel_children(adns_query qu);
622 void adns__procdgram(adns_state ads, const byte *dgram, int len,
623 int serv, int viatcp, struct timeval now);
624 /* This function is allowed to cause new datagrams to be constructed
625 * and sent, or even new queries to be started. However,
626 * query-sending functions are not allowed to call any general event
627 * loop functions in case they accidentally call this.
629 * Ie, receiving functions may call sending functions.
630 * Sending functions may NOT call receiving functions.
635 const typeinfo *adns__findtype(adns_rrtype type);
644 int dglen, max, cbyte, namelen;
648 void adns__findlabel_start(findlabel_state *fls, adns_state ads,
649 int serv, adns_query qu,
650 const byte *dgram, int dglen, int max,
651 int dmbegin, int *dmend_rlater);
652 /* Finds labels in a domain in a datagram.
654 * Call this routine first.
655 * dmend_rlater may be null. ads (and of course fls) may not be.
656 * serv may be -1, qu may be null - they are for error reporting.
659 adns_status adns__findlabel_next(findlabel_state *fls,
660 int *lablen_r, int *labstart_r);
661 /* Then, call this one repeatedly.
663 * It will return adns_s_ok if all is well, and tell you the length
664 * and start of successive labels. labstart_r may be null, but
665 * lablen_r must not be.
667 * After the last label, it will return with *lablen_r zero.
668 * Do not then call it again; instead, just throw away the findlabel_state.
670 * *dmend_rlater will have been set to point to the next part of
671 * the datagram after the label (or after the uncompressed part,
672 * if compression was used). *namelen_rlater will have been set
673 * to the length of the domain name (total length of labels plus
674 * 1 for each intervening dot).
676 * If the datagram appears to be truncated, *lablen_r will be -1.
677 * *dmend_rlater, *labstart_r and *namelen_r may contain garbage.
678 * Do not call _next again.
680 * There may also be errors, in which case *dmend_rlater,
681 * *namelen_rlater, *lablen_r and *labstart_r may contain garbage.
682 * Do not then call findlabel_next again.
689 adns_status adns__parse_domain(adns_state ads, int serv, adns_query qu,
690 vbuf *vb, parsedomain_flags flags,
691 const byte *dgram, int dglen, int *cbyte_io,
693 /* vb must already have been initialised; it will be reset if necessary.
694 * If there is truncation, vb->used will be set to 0; otherwise
695 * (if there is no error) vb will be null-terminated.
696 * If there is an error vb and *cbyte_io may be left indeterminate.
698 * serv may be -1 and qu may be 0 - they are used for error reporting only.
701 adns_status adns__parse_domain_more(findlabel_state *fls, adns_state ads,
702 adns_query qu, vbuf *vb,
703 parsedomain_flags flags,
705 /* Like adns__parse_domain, but you pass it a pre-initialised findlabel_state,
706 * for continuing an existing domain or some such of some kind. Also, unlike
707 * _parse_domain, the domain data will be appended to vb, rather than replacing
708 * the existing contents.
711 adns_status adns__findrr(adns_query qu, int serv,
712 const byte *dgram, int dglen, int *cbyte_io,
713 int *type_r, int *class_r, unsigned long *ttl_r,
714 int *rdlen_r, int *rdstart_r,
715 int *ownermatchedquery_r);
716 /* Finds the extent and some of the contents of an RR in a datagram
717 * and does some checks. The datagram is *dgram, length dglen, and
718 * the RR starts at *cbyte_io (which is updated afterwards to point
719 * to the end of the RR).
721 * The type, class, TTL and RRdata length and start are returned iff
722 * the corresponding pointer variables are not null. type_r, class_r
723 * and ttl_r may not be null. The TTL will be capped.
725 * If ownermatchedquery_r != 0 then the owner domain of this
726 * RR will be compared with that in the query (or, if the query
727 * has gone to a CNAME lookup, with the canonical name).
728 * In this case, *ownermatchedquery_r will be set to 0 or 1.
729 * The query datagram (or CNAME datagram) MUST be valid and not truncated.
731 * If there is truncation then *type_r will be set to -1 and
732 * *cbyte_io, *class_r, *rdlen_r, *rdstart_r and *eo_matched_r will be
735 * qu must obviously be non-null.
737 * If an error is returned then *type_r will be undefined too.
740 adns_status adns__findrr_anychk(adns_query qu, int serv,
741 const byte *dgram, int dglen, int *cbyte_io,
742 int *type_r, int *class_r,
743 unsigned long *ttl_r,
744 int *rdlen_r, int *rdstart_r,
745 const byte *eo_dgram, int eo_dglen,
746 int eo_cbyte, int *eo_matched_r);
747 /* Like adns__findrr_checked, except that the datagram and
748 * owner to compare with can be specified explicitly.
750 * If the caller thinks they know what the owner of the RR ought to
751 * be they can pass in details in eo_*: this is another (or perhaps
752 * the same datagram), and a pointer to where the putative owner
753 * starts in that datagram. In this case *eo_matched_r will be set
754 * to 1 if the datagram matched or 0 if it did not. Either
755 * both eo_dgram and eo_matched_r must both be non-null, or they
756 * must both be null (in which case eo_dglen and eo_cbyte will be ignored).
757 * The eo datagram and contained owner domain MUST be valid and
761 void adns__update_expires(adns_query qu, unsigned long ttl,
763 /* Updates the `expires' field in the query, so that it doesn't exceed
767 int vbuf__append_quoted1035(vbuf *vb, const byte *buf, int len);
771 void adns__tcp_broken(adns_state ads, const char *what, const char *why);
772 /* what and why may be both 0, or both non-0. */
774 void adns__tcp_tryconnect(adns_state ads, struct timeval now);
776 void adns__autosys(adns_state ads, struct timeval now);
777 /* Make all the system calls we want to if the application wants us to.
778 * Must not be called from within adns internal processing functions,
779 * lest we end up in recursive descent !
782 void adns__must_gettimeofday(adns_state ads, const struct timeval **now_io,
783 struct timeval *tv_buf);
785 int adns__pollfds(adns_state ads, struct pollfd pollfds_buf[MAX_POLLFDS]);
786 void adns__fdevents(adns_state ads,
787 const struct pollfd *pollfds, int npollfds,
788 int maxfd, const fd_set *readfds,
789 const fd_set *writefds, const fd_set *exceptfds,
790 struct timeval now, int *r_r);
791 int adns__internal_check(adns_state ads,
792 adns_query *query_io,
793 adns_answer **answer,
796 void adns__timeouts(adns_state ads, int act,
797 struct timeval **tv_io, struct timeval *tvbuf,
799 /* If act is !0, then this will also deal with the TCP connection
800 * if previous events broke it or require it to be connected.
805 void adns__consistency(adns_state ads, adns_query qu, consistency_checks cc);
807 /* Useful static inline functions: */
809 static inline int ctype_whitespace(int c) {
810 return c==' ' || c=='\n' || c=='\t';
812 static inline int ctype_digit(int c) { return c>='0' && c<='9'; }
813 static inline int ctype_alpha(int c) {
814 return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z');
816 static inline int ctype_822special(int c) {
817 return strchr("()<>@,;:\\\".[]",c) != 0;
819 static inline int ctype_domainunquoted(int c) {
820 return ctype_alpha(c) || ctype_digit(c) || (strchr("-_/+",c) != 0);
823 static inline int errno_resources(int e) { return e==ENOMEM || e==ENOBUFS; }
827 #define MEM_ROUND(sz) \
828 (( ((sz)+sizeof(union maxalign)-1) / sizeof(union maxalign) ) \
829 * sizeof(union maxalign) )
831 #define GETIL_B(cb) (((dgram)[(cb)++]) & 0x0ff)
832 #define GET_B(cb,tv) ((tv)= GETIL_B((cb)))
833 #define GET_W(cb,tv) ((tv)=0,(tv)|=(GETIL_B((cb))<<8), (tv)|=GETIL_B(cb), (tv))
834 #define GET_L(cb,tv) ( (tv)=0, \
835 (tv)|=(GETIL_B((cb))<<24), \
836 (tv)|=(GETIL_B((cb))<<16), \
837 (tv)|=(GETIL_B((cb))<<8), \