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1 /*	$NetBSD: resolv.h,v 1.31 2005/12/26 19:01:47 perry Exp $	*/
2 
3 /*
4  * Copyright (c) 1983, 1987, 1989
5  *    The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 /*
33  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
34  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
35  *
36  * Permission to use, copy, modify, and distribute this software for any
37  * purpose with or without fee is hereby granted, provided that the above
38  * copyright notice and this permission notice appear in all copies.
39  *
40  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
41  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
42  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
43  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
44  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
45  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
46  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
47  */
48 
49 /*
50  *	@(#)resolv.h	8.1 (Berkeley) 6/2/93
51  *	Id: resolv.h,v 1.7.2.11.4.2 2004/06/25 00:41:05 marka Exp
52  */
53 
54 #pragma once
55 
56 #include <sys/cdefs.h>
57 
58 #include <resolv.h>
59 #include "resolv_static.h"
60 #include "resolv_params.h"
61 #include "resolv_stats.h"
62 #include <net/if.h>
63 #include <time.h>
64 
65 __BEGIN_DECLS
66 
67 // Linux defines MAXHOSTNAMELEN as 64, while the domain name limit in
68 // RFC 1034 and RFC 1035 is 255 octets.
69 #ifdef MAXHOSTNAMELEN
70 #undef MAXHOSTNAMELEN
71 #endif
72 #define MAXHOSTNAMELEN 256
73 
74 /*
75  * Revision information.  This is the release date in YYYYMMDD format.
76  * It can change every day so the right thing to do with it is use it
77  * in preprocessor commands such as "#if (__RES > 19931104)".  Do not
78  * compare for equality; rather, use it to determine whether your resolver
79  * is new enough to contain a certain feature.
80  */
81 
82 #define	__RES	20030124
83 
84 /*
85  * This used to be defined in res_query.c, now it's in herror.c.
86  * [XXX no it's not.  It's in irs/irs_data.c]
87  * It was
88  * never extern'd by any *.h file before it was placed here.  For thread
89  * aware programs, the last h_errno value set is stored in res->h_errno.
90  *
91  * XXX:	There doesn't seem to be a good reason for exposing RES_SET_H_ERRNO
92  *	(and __h_errno_set) to the public via <resolv.h>.
93  * XXX:	__h_errno_set is really part of IRS, not part of the resolver.
94  *	If somebody wants to build and use a resolver that doesn't use IRS,
95  *	what do they do?  Perhaps something like
96  *		#ifdef WANT_IRS
97  *		# define RES_SET_H_ERRNO(r,x) __h_errno_set(r,x)
98  *		#else
99  *		# define RES_SET_H_ERRNO(r,x) (h_errno = (r)->res_h_errno = (x))
100  *		#endif
101  */
102 
103 #define RES_SET_H_ERRNO(r,x) (h_errno = (r)->res_h_errno = (x))
104 struct __res_state; /* forward */
105 
106 /*
107  * Resolver configuration file.
108  * Normally not present, but may contain the address of the
109  * initial name server(s) to query and the domain search list.
110  */
111 
112 #ifndef _PATH_RESCONF
113 #ifdef ANDROID_CHANGES
114 #define _PATH_RESCONF        "/etc/ppp/resolv.conf"
115 #else
116 #define _PATH_RESCONF        "/etc/resolv.conf"
117 #endif
118 #endif
119 
120 struct res_sym {
121 	int		number;	   /* Identifying number, like T_MX */
122 	const char *	name;	   /* Its symbolic name, like "MX" */
123 	const char *	humanname; /* Its fun name, like "mail exchanger" */
124 };
125 
126 /*
127  * Global defines and variables for resolver stub.
128  */
129 #define	MAXDFLSRCH		3	/* # default domain levels to try */
130 #define	LOCALDOMAINPARTS	2	/* min levels in name that is "local" */
131 
132 #define	RES_TIMEOUT		5	/* min. seconds between retries */
133 #define	MAXRESOLVSORT		10	/* number of net to sort on */
134 #define	RES_MAXNDOTS		15	/* should reflect bit field size */
135 #define	RES_MAXRETRANS		30	/* only for resolv.conf/RES_OPTIONS */
136 #define	RES_MAXRETRY		5	/* only for resolv.conf/RES_OPTIONS */
137 #define	RES_DFLRETRY		2	/* Default #/tries. */
138 #define	RES_MAXTIME		65535	/* Infinity, in milliseconds. */
139 
140 struct __res_state_ext;
141 
142 struct __res_state {
143 	unsigned	netid;			/* NetId: cache key and socket mark */
144 	int	retrans;	 	/* retransmission time interval */
145 	int	retry;			/* number of times to retransmit */
146 #ifdef sun
147 	u_int	options;		/* option flags - see below. */
148 #else
149 	u_long	options;		/* option flags - see below. */
150 #endif
151 	int	nscount;		/* number of name servers */
152 	struct sockaddr_in
153 		nsaddr_list[MAXNS];	/* address of name server */
154 #define	nsaddr	nsaddr_list[0]		/* for backward compatibility */
155 	u_short	id;			/* current message id */
156 	char	*dnsrch[MAXDNSRCH+1];	/* components of domain to search */
157 	char	defdname[256];		/* default domain (deprecated) */
158 #ifdef sun
159 	u_int	pfcode;			/* RES_PRF_ flags - see below. */
160 #else
161 	u_long	pfcode;			/* RES_PRF_ flags - see below. */
162 #endif
163 	unsigned ndots:4;		/* threshold for initial abs. query */
164 	unsigned nsort:4;		/* number of elements in sort_list[] */
165 	char	unused[3];
166 	struct {
167 		struct in_addr	addr;
168 		uint32_t	mask;
169 	} sort_list[MAXRESOLVSORT];
170 #ifdef __OLD_RES_STATE
171 	char lookups[4];
172 #else
173 	res_send_qhook qhook;		/* query hook */
174 	res_send_rhook rhook;		/* response hook */
175 	int	res_h_errno;		/* last one set for this context */
176 	unsigned _mark;			/* If non-0 SET_MARK to _mark on all request sockets */
177 	int	_vcsock;		/* PRIVATE: for res_send VC i/o */
178 	u_int	_flags;			/* PRIVATE: see below */
179 	u_int	_pad;			/* make _u 64 bit aligned */
180 	union {
181 		/* On an 32-bit arch this means 512b total. */
182 		char	pad[72 - 4*sizeof (int) - 2*sizeof (void *)];
183 		struct {
184 			uint16_t		nscount;
185 			uint16_t		nstimes[MAXNS];	/* ms. */
186 			int			nssocks[MAXNS];
187 			struct __res_state_ext *ext;	/* extention for IPv6 */
188 		} _ext;
189 	} _u;
190 #endif
191         struct res_static   rstatic[1];
192 };
193 
194 typedef struct __res_state *res_state;
195 
196 /* Retrieve a local copy of the stats for the given netid. The buffer must have space for
197  * MAXNS __resolver_stats. Returns the revision id of the resolvers used.
198  */
199 __LIBC_HIDDEN__
200 extern int
201 _resolv_cache_get_resolver_stats( unsigned netid, struct __res_params* params,
202         struct __res_stats stats[MAXNS]);
203 
204 /* Add a sample to the shared struct for the given netid and server, provided that the
205  * revision_id of the stored servers has not changed.
206  */
207 __LIBC_HIDDEN__
208 extern void
209 _resolv_cache_add_resolver_stats_sample( unsigned netid, int revision_id, int ns,
210         const struct __res_sample* sample, int max_samples);
211 
212 /* End of stats related definitions */
213 
214 union res_sockaddr_union {
215 	struct sockaddr_in	sin;
216 #ifdef IN6ADDR_ANY_INIT
217 	struct sockaddr_in6	sin6;
218 #endif
219 #ifdef ISC_ALIGN64
220 	int64_t			__align64;	/* 64bit alignment */
221 #else
222 	int32_t			__align32;	/* 32bit alignment */
223 #endif
224 	char			__space[128];   /* max size */
225 };
226 
227 /*
228  * Resolver flags (used to be discrete per-module statics ints).
229  */
230 #define	RES_F_VC	0x00000001	/* socket is TCP */
231 #define	RES_F_CONN	0x00000002	/* socket is connected */
232 #define	RES_F_EDNS0ERR	0x00000004	/* EDNS0 caused errors */
233 #define	RES_F__UNUSED	0x00000008	/* (unused) */
234 #define	RES_F_LASTMASK	0x000000F0	/* ordinal server of last res_nsend */
235 #define	RES_F_LASTSHIFT	4		/* bit position of LASTMASK "flag" */
236 #define	RES_GETLAST(res) (((res)._flags & RES_F_LASTMASK) >> RES_F_LASTSHIFT)
237 
238 /* res_findzonecut2() options */
239 #define	RES_EXHAUSTIVE	0x00000001	/* always do all queries */
240 #define	RES_IPV4ONLY	0x00000002	/* IPv4 only */
241 #define	RES_IPV6ONLY	0x00000004	/* IPv6 only */
242 
243 /*
244  * Resolver options (keep these in synch with res_debug.c, please)
245  */
246 #define RES_INIT	0x00000001	/* address initialized */
247 #define RES_DEBUG	0x00000002	/* print debug messages */
248 #define RES_AAONLY	0x00000004	/* authoritative answers only (!IMPL)*/
249 #define RES_USEVC	0x00000008	/* use virtual circuit */
250 #define RES_PRIMARY	0x00000010	/* query primary server only (!IMPL) */
251 #define RES_IGNTC	0x00000020	/* ignore trucation errors */
252 #define RES_RECURSE	0x00000040	/* recursion desired */
253 #define RES_DEFNAMES	0x00000080	/* use default domain name */
254 #define RES_STAYOPEN	0x00000100	/* Keep TCP socket open */
255 #define RES_DNSRCH	0x00000200	/* search up local domain tree */
256 #define	RES_INSECURE1	0x00000400	/* type 1 security disabled */
257 #define	RES_INSECURE2	0x00000800	/* type 2 security disabled */
258 #define	RES_NOALIASES	0x00001000	/* shuts off HOSTALIASES feature */
259 #define	RES_USE_INET6	0x00002000	/* use/map IPv6 in gethostbyname() */
260 #define RES_ROTATE	0x00004000	/* rotate ns list after each query */
261 #define	RES_NOCHECKNAME	0x00008000	/* do not check names for sanity. */
262 #define	RES_KEEPTSIG	0x00010000	/* do not strip TSIG records */
263 #define	RES_BLAST	0x00020000	/* blast all recursive servers */
264 #define RES_NOTLDQUERY	0x00100000	/* don't unqualified name as a tld */
265 #define RES_USE_DNSSEC	0x00200000	/* use DNSSEC using OK bit in OPT */
266 /* #define RES_DEBUG2	0x00400000 */	/* nslookup internal */
267 /* KAME extensions: use higher bit to avoid conflict with ISC use */
268 #define RES_USE_DNAME	0x10000000	/* use DNAME */
269 #define RES_USE_EDNS0	0x40000000	/* use EDNS0 if configured */
270 #define RES_NO_NIBBLE2	0x80000000	/* disable alternate nibble lookup */
271 
272 #define RES_DEFAULT	(RES_RECURSE | RES_DEFNAMES | \
273 			 RES_DNSRCH | RES_NO_NIBBLE2)
274 
275 /*
276  * Resolver "pfcode" values.  Used by dig.
277  */
278 #define RES_PRF_STATS	0x00000001
279 #define RES_PRF_UPDATE	0x00000002
280 #define RES_PRF_CLASS   0x00000004
281 #define RES_PRF_CMD	0x00000008
282 #define RES_PRF_QUES	0x00000010
283 #define RES_PRF_ANS	0x00000020
284 #define RES_PRF_AUTH	0x00000040
285 #define RES_PRF_ADD	0x00000080
286 #define RES_PRF_HEAD1	0x00000100
287 #define RES_PRF_HEAD2	0x00000200
288 #define RES_PRF_TTLID	0x00000400
289 #define RES_PRF_HEADX	0x00000800
290 #define RES_PRF_QUERY	0x00001000
291 #define RES_PRF_REPLY	0x00002000
292 #define RES_PRF_INIT	0x00004000
293 #define RES_PRF_TRUNC	0x00008000
294 /*			0x00010000	*/
295 
296 /* Things involving an internal (static) resolver context. */
297 __LIBC_HIDDEN__ extern struct __res_state *__res_get_state(void);
298 __LIBC_HIDDEN__ extern void __res_put_state(struct __res_state *);
299 
300 #ifndef ANDROID_CHANGES
301 /*
302  * Source and Binary compatibility; _res will not work properly
303  * with multi-threaded programs.
304  */
305 extern struct __res_state *__res_state(void);
306 #define _res (*__res_state())
307 #endif
308 
309 #ifndef __BIND_NOSTATIC
310 #define fp_nquery		__fp_nquery
311 #define fp_query		__fp_query
312 #define hostalias		__hostalias
313 #define p_query			__p_query
314 #define res_close		__res_close
315 #define res_opt			__res_opt
316 #define res_isourserver		__res_isourserver
317 #define	res_querydomain		__res_querydomain
318 #define res_send		__res_send
319 
320 #ifdef BIND_RES_POSIX3
321 #define	dn_expand	__dn_expand
322 #define	res_init	__res_init
323 #define	res_query	__res_query
324 #define	res_search	__res_search
325 #define	res_mkquery	__res_mkquery
326 #endif
327 
328 void		fp_nquery(const u_char *, int, FILE *);
329 void		fp_query(const u_char *, FILE *);
330 const char *	hostalias(const char *);
331 void		p_query(const u_char *);
332 void		res_close(void);
333 int		res_init(void);
334 __LIBC_HIDDEN__ int		res_opt(int, u_char *, int, int);
335 int		res_isourserver(const struct sockaddr_in *);
336 int		res_mkquery(int, const char *, int, int, const u_char *, int, const u_char *, u_char *, int);
337 int		res_query(const char *, int, int, u_char *, int);
338 int		res_querydomain(const char *, const char *, int, int, u_char *, int);
339 int		res_search(const char *, int, int, u_char *, int);
340 int		res_send(const u_char *, int, u_char *, int);
341 #endif
342 
343 #if !defined(SHARED_LIBBIND) || defined(LIB)
344 /*
345  * If libbind is a shared object (well, DLL anyway)
346  * these externs break the linker when resolv.h is
347  * included by a lib client (like named)
348  * Make them go away if a client is including this
349  *
350  */
351 __LIBC_HIDDEN__ extern const struct res_sym __p_key_syms[];
352 __LIBC_HIDDEN__ extern const struct res_sym __p_cert_syms[];
353 extern const struct res_sym __p_class_syms[];
354 extern const struct res_sym __p_type_syms[];
355 __LIBC_HIDDEN__ extern const struct res_sym __p_rcode_syms[];
356 #endif /* SHARED_LIBBIND */
357 
358 #ifndef ANDROID_CHANGES
359 #define dn_comp			__dn_comp
360 #endif
361 #define dn_count_labels		__dn_count_labels
362 #define dn_skipname		__dn_skipname
363 #define fp_resstat		__fp_resstat
364 #define loc_aton		__loc_aton
365 #define loc_ntoa		__loc_ntoa
366 #define p_cdname		__p_cdname
367 #define p_cdnname		__p_cdnname
368 #define p_class			__p_class
369 #define p_fqname		__p_fqname
370 #define p_fqnname		__p_fqnname
371 #define p_option		__p_option
372 #define p_secstodate		__p_secstodate
373 #define p_section		__p_section
374 #define p_time			__p_time
375 #define p_type			__p_type
376 #define p_rcode			__p_rcode
377 #define p_sockun		__p_sockun
378 #define putlong			__putlong
379 #define putshort		__putshort
380 #define res_dnok		__res_dnok
381 #define res_findzonecut		__res_findzonecut
382 #define res_findzonecut2	__res_findzonecut2
383 #define res_hnok		__res_hnok
384 #define res_hostalias		__res_hostalias
385 #define res_mailok		__res_mailok
386 #define res_nameinquery		__res_nameinquery
387 #define res_nclose		__res_nclose
388 #define res_ninit		__res_ninit
389 #define res_nmkquery		__res_nmkquery
390 #define res_pquery		__res_pquery
391 #define res_nquery		__res_nquery
392 #define res_nquerydomain	__res_nquerydomain
393 #define res_nsearch		__res_nsearch
394 #define res_nsend		__res_nsend
395 #define res_nsendsigned		__res_nsendsigned
396 #define res_nisourserver	__res_nisourserver
397 #define res_ownok		__res_ownok
398 #define res_queriesmatch	__res_queriesmatch
399 #define sym_ntop		__sym_ntop
400 #define sym_ntos		__sym_ntos
401 #define sym_ston		__sym_ston
402 #define res_nopt		__res_nopt
403 #define res_ndestroy		__res_ndestroy
404 #define	res_nametoclass		__res_nametoclass
405 #define	res_nametotype		__res_nametotype
406 #define	res_setservers		__res_setservers
407 #define	res_getservers		__res_getservers
408 #define	res_buildprotolist	__res_buildprotolist
409 #define	res_destroyprotolist	__res_destroyprotolist
410 #define	res_destroyservicelist	__res_destroyservicelist
411 #define	res_get_nibblesuffix	__res_get_nibblesuffix
412 #define	res_get_nibblesuffix2	__res_get_nibblesuffix2
413 #define	res_ourserver_p		__res_ourserver_p
414 #define	res_protocolname	__res_protocolname
415 #define	res_protocolnumber	__res_protocolnumber
416 #define	res_send_setqhook	__res_send_setqhook
417 #define	res_send_setrhook	__res_send_setrhook
418 #define	res_servicename		__res_servicename
419 #define	res_servicenumber	__res_servicenumber
420 int		res_hnok(const char *);
421 int		res_ownok(const char *);
422 int		res_mailok(const char *);
423 int		res_dnok(const char *);
424 int		sym_ston(const struct res_sym *, const char *, int *);
425 const char *	sym_ntos(const struct res_sym *, int, int *);
426 const char *	sym_ntop(const struct res_sym *, int, int *);
427 #ifndef ANDROID_CHANGES
428 int		b64_ntop(u_char const *, size_t, char *, size_t);
429 int		b64_pton(char const *, u_char *, size_t);
430 #endif
431 int		loc_aton(const char *, u_char *);
432 const char *	loc_ntoa(const u_char *, char *, size_t);
433 int		dn_skipname(const u_char *, const u_char *);
434 void		putlong(uint32_t, u_char *);
435 void		putshort(uint16_t, u_char *);
436 #ifndef __ultrix__
437 uint16_t	_getshort(const u_char *);
438 uint32_t	_getlong(const u_char *);
439 #endif
440 const char *	p_class(int);
441 const char *	p_time(uint32_t);
442 const char *	p_type(int);
443 const char *	p_rcode(int);
444 __LIBC_HIDDEN__ const char *	p_sockun(union res_sockaddr_union, char *, size_t);
445 const u_char *	p_cdnname(const u_char *, const u_char *, int, FILE *);
446 const u_char *	p_cdname(const u_char *, const u_char *, FILE *);
447 const u_char *	p_fqnname(const u_char *, const u_char *,
448 			       int, char *, int);
449 const u_char *	p_fqname(const u_char *, const u_char *, FILE *);
450 const char *	p_option(u_long);
451 char *		p_secstodate(u_long);
452 int		dn_count_labels(const char *);
453 int		res_nameinquery(const char *, int, int, const u_char *,
454 				     const u_char *);
455 int		res_queriesmatch(const u_char *, const u_char *,
456 				      const u_char *, const u_char *);
457 __LIBC_HIDDEN__ const char *	p_section(int, int);
458 /* Things involving a resolver context. */
459 int		res_ninit(res_state);
460 int		res_nisourserver(const res_state, const struct sockaddr_in *);
461 void		fp_resstat(const res_state, FILE *);
462 __LIBC_HIDDEN__ void		res_pquery(const res_state, const u_char *, int, FILE *);
463 const char *	res_hostalias(const res_state, const char *, char *, size_t);
464 int		res_nquery(res_state, const char *, int, int, u_char *, int);
465 int		res_nsearch(res_state, const char *, int, int, u_char *, int);
466 int		res_nquerydomain(res_state, const char *, const char *,
467 				      int, int, u_char *, int);
468 int		res_nmkquery(res_state, int, const char *, int, int,
469 				  const u_char *, int, const u_char *,
470 				  u_char *, int);
471 int		res_nsend(res_state, const u_char *, int, u_char *, int);
472 int		res_nsendsigned(res_state, const u_char *, int,
473 				     ns_tsig_key *, u_char *, int);
474 int		res_findzonecut(res_state, const char *, ns_class, int,
475 				     char *, size_t, struct in_addr *, int);
476 int		res_findzonecut2(res_state, const char *, ns_class, int,
477 				      char *, size_t,
478 				      union res_sockaddr_union *, int);
479 void		res_nclose(res_state);
480 __LIBC_HIDDEN__ int		res_nopt(res_state, int, u_char *, int, int);
481 void		res_send_setqhook(res_send_qhook);
482 void		res_send_setrhook(res_send_rhook);
483 __LIBC_HIDDEN__ int		__res_vinit(res_state, int);
484 void		res_destroyservicelist(void);
485 const char *	res_servicename(uint16_t, const char *);
486 const char *	res_protocolname(int);
487 void		res_destroyprotolist(void);
488 void		res_buildprotolist(void);
489 __LIBC_HIDDEN__ const char *	res_get_nibblesuffix(res_state);
490 __LIBC_HIDDEN__ const char *	res_get_nibblesuffix2(res_state);
491 __LIBC_HIDDEN__ void		res_ndestroy(res_state);
492 __LIBC_HIDDEN__ uint16_t	res_nametoclass(const char *, int *);
493 __LIBC_HIDDEN__ uint16_t	res_nametotype(const char *, int *);
494 __LIBC_HIDDEN__ void		res_setservers(res_state,
495 				    const union res_sockaddr_union *, int);
496 __LIBC_HIDDEN__ int		res_getservers(res_state,
497 				    union res_sockaddr_union *, int);
498 
499 struct android_net_context; /* forward */
500 __LIBC_HIDDEN__ void res_setnetcontext(res_state, const struct android_net_context *);
501 
502 // We use the OpenBSD __res_randomid...
503 u_int __res_randomid(void);
504 // ...but NetBSD calls it res_randomid.
505 #define res_randomid __res_randomid
506 
507 #ifdef __i386__
508 # define __socketcall extern __attribute__((__cdecl__))
509 #else
510 # define __socketcall extern
511 #endif
512 
513 __socketcall int __connect(int, const struct sockaddr*, socklen_t);
514 
515 #undef __socketcall
516 
517 // Symbols that are supposed to be in resolv.h, but that we aren't exporting.
518 int ns_parserr2(ns_msg*, ns_sect, int, ns_rr2*);
519 int ns_name_pton2(const char*, u_char*, size_t, size_t*);
520 int ns_name_unpack2(const u_char*, const u_char*, const u_char*, u_char*, size_t, size_t*);
521 int ns_name_eq(ns_nname_ct, size_t, ns_nname_ct, size_t);
522 int ns_name_owned(ns_namemap_ct, int, ns_namemap_ct, int);
523 int ns_name_map(ns_nname_ct, size_t, ns_namemap_t, int);
524 int ns_name_labels(ns_nname_ct, size_t);
525 
526 __END_DECLS
527