3 #ifndef ADNS_H_INCLUDED
4 #define ADNS_H_INCLUDED
6 #include <sys/socket.h>
7 #include <netinet/in.h>
9 typedef struct adns__state
*adns_state
;
10 typedef struct adns__query
*adns_query
;
13 adns_if_noenv
= 0x0001, /* do not look at environment */
14 adns_if_noerrprint
= 0x0002, /* never print output to stderr */
15 adns_if_debug
= 0x0004, /* print debugging output to stderr */
16 adns_if_noautosys
= 0x0008, /* do not do full flow-of-control whenever we can */
20 adns_f_search
= 0x0001, /* use the searchlist */
21 adns_f_usevc
= 0x0002, /* use a virtual circuit (TCP connection) */
22 adns_f_anyquote
= 0x0004,
26 adns__rrt_typemask
= 0x0ffff,
27 adns__qtf_deref
= 0x10000, /* dereference domains and produce extra data */
28 adns__qtf_mailconv
= 0x20000, /* put @ between first and second labels */
32 adns_r_ns
= adns_r_ns_raw
|adns__qtf_deref
,
35 adns_r_soa
= adns_r_soa_raw
|adns__qtf_mailconv
,
38 adns_r_ptr
= adns_r_ptr_raw
|adns__qtf_deref
,
41 adns_r_mx
= adns_r_mx_raw
|adns__qtf_deref
,
44 adns_r_rp
= adns_r_rp_raw
|adns__qtf_mailconv
47 /* In queries without qtf_anyquote, all domains must have standard
48 * legal syntax. In queries _with_ qtf_anyquote, domains in the query
49 * or response may contain any characters, quoted according to
50 * RFC1035 5.1. On input to adns, the char* is a pointer to the
51 * interior of a " delimited string, except that " may appear in it,
52 * and on output, the char* is a pointer to a string which would be
53 * legal either inside or outside " delimiters, and any characters
54 * not usually legal in domain names will be quoted as \X
55 * (if the character is 33-126 except \ and ") or \DDD.
57 * Do not ask for records containing mailboxes without
58 * specifying qtf_mailconv or qtf_anyquote.
68 adns_s_max_tempfail
= 99,
71 adns_s_inconsistent
, /* for bad PTR */
75 /* In dereferenced answers, multiple addresses show up as multiple
76 * answers with all the dm pointers being the same, with ref= adns_s_ok.
77 * If no address is available then INADDR_NONE is used, and ref indicates
84 int naddrs
; /* temp fail => -1, perm fail => 0, s_ok => >0 */
85 struct in_addr
*addrs
;
90 char *cname
; /* always NULL if query was for CNAME records */
94 struct in_addr inaddr
[1]; /* a */
95 char (*str
)[1]; /* ns_raw, cname, ptr, ptr_raw, txt */
96 adns_dmaddr dmaddr
[1]; /* ns */
97 struct { char *a
, *b
; } strpair
[1]; /* hinfo, rp, rp_raw */
98 struct { int pref
; adns_dmaddrs dmaddr
; } intdmaddr
[1]; /* mx */
99 struct { int pref
; char *str
; } intstr
[1]; /* mx_raw */
102 unsigned long serial
, refresh
, retry
, expire
, minimum
;
103 } soa
[1]; /* soa, soa_raw */
108 /* Memory management:
109 * adns_state and adns_query are actually pointers to malloc'd state;
110 * On submission questions are copied, including the owner domain;
111 * Answers are malloc'd as a single piece of memory.
113 * Must always be non-null pointer;
114 * If *query_io is 0 to start with then any query may be returned;
115 * If *query_io is !0 adns_query then only that query may be returned.
117 * Return values are 0 or an errno value;
118 * Seriously fatal system errors (eg, failure to create sockets,
119 * malloc failure, etc.) return errno values;
120 * Other errors (nameserver failure, timed out connections, &c)
121 * are returned in the status field of the answer. If status is
122 * nonzero then nrrs will be 0, otherwise it will be >0.
123 * type will always be the type requested;
124 * If no (appropriate) requests are done adns_check returns EWOULDBLOCK;
125 * If no (appropriate) requests are outstanding adns_query and adns_wait return ESRCH;
126 * If malloc failure occurs during internal allocation or processing
127 * ands_check and _wait set *answer to 0.
130 int adns_init(adns_state
*newstate_r
, adns_initflags flags
);
132 int adns_synchronous(adns_state ads
,
135 adns_queryflags flags
,
136 adns_answer
**answer_r
);
137 /* Will not return EINTR. */
139 /* NB: if you set adns_if_noautosys then _submit and _check do not
140 * make any system calls; you must use adns_callback (possibly after
141 * adns_interest) to actually get things to happen.
144 int adns_submit(adns_state ads
,
147 adns_queryflags flags
,
149 adns_query
*query_r
);
151 int adns_check(adns_state ads
,
152 adns_query
*query_io
,
153 adns_answer
**answer_r
,
156 int adns_wait(adns_state ads
,
157 adns_query
*query_io
,
158 adns_answer
**answer_r
,
160 /* Might return EINTR - if so, try again */
162 void adns_cancel(adns_state ads
, adns_query query
);
164 int adns_finish(adns_state
);
166 int adns_callback(adns_state
, int maxfd
, const fd_set
*readfds
, const fd_set
*writefds
,
167 const fd_set
*exceptfds
);
168 /* Gives adns flow-of-control for a bit. This will never block.
169 * If maxfd == -1 then adns will check (make nonblocking system calls on)
170 * all of its own filedescriptors; otherwise it will only use those
171 * < maxfd and specified in the fd_set's, as if select had returned them.
172 * Other fd's may be in the fd_sets, and will be ignored.
173 * _callback returns how many adns fd's were in the various sets, so
174 * you can tell if your select handling code has missed something and is going awol.
177 void adns_interest(adns_state
, int *maxfd_io
, fd_set
*readfds_io
,
178 fd_set
*writefds_io
, fd_set
*exceptfds_io
,
179 struct timeval
**tv_mod
, struct timeval
*tv_buf
);
180 /* Find out file descriptors adns is interested in, and when it
181 * would like the opportunity to time something out. If you do not plan to
182 * block then tv_mod may be 0. Otherwise, tv_mod may point to 0 meaning
183 * you have no timeout of your own, in which case tv_buf must be non-null and
184 * _interest may fill it in and set *tv_mod=tv_buf.
185 * readfds, writefds, exceptfds and maxfd may not be 0.
188 /* Example expected/legal calling sequences:
194 * adns_check 3 -> EWOULDBLOCK
200 * adns_init _noautosys
206 * adns_submit / adns_check