* - adns user-visible API (single-threaded, without any locking)
*/
/*
- * This file is part of adns, which is Copyright (C) 1997-1999 Ian Jackson
+ *
+ * This file is
+ * Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk>
+ *
+ * It is part of adns, which is
+ * Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk>
+ * Copyright (C) 1999 Tony Finch <dot@dotat.at>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
+ *
+ *
+ * For the benefit of certain LGPL'd `omnibus' software which provides
+ * a uniform interface to various things including adns, I make the
+ * following additional licence. I do this because the GPL would
+ * otherwise force either the omnibus software to be GPL'd or for the
+ * adns-using part to be distributed separately.
*
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software Foundation,
+ * So, you may also redistribute and/or modify adns.h (but only the
+ * public header file adns.h and not any other part of adns) under the
+ * terms of the GNU Library General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * Note that adns itself is GPL'd. Authors of adns-using applications
+ * with GPL-incompatible licences, and people who distribute adns with
+ * applications where the whole distribution is not GPL'd, are still
+ * likely to be in violation of the GPL. Anyone who wants to do this
+ * should contact Ian Jackson. Please note that to avoid encouraging
+ * people to infringe the GPL as it applies the body of adns, I think
+ * that if you take advantage of the special exception to redistribute
+ * just adns.h under the LGPL, you should retain this paragraph in its
+ * place in the appropriate copyright statements.
+ *
+ *
+ * You should have received a copy of the GNU General Public License,
+ * or the GNU Library General Public License, as appropriate, along
+ * with this program; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
+ *
* $Id$
*/
adns_if_noerrprint= 0x0002, /* never print output to stderr (_debug overrides) */
adns_if_noserverwarn= 0x0004, /* do not warn to stderr about duff nameservers etc */
adns_if_debug= 0x0008, /* enable all output to stderr plus debug msgs */
+ adns_if_logpid= 0x0080, /* include pid in diagnostic output */
adns_if_noautosys= 0x0010, /* do not make syscalls at every opportunity */
adns_if_eintr= 0x0020, /* allow _wait and _synchronous to return EINTR */
adns_if_nosigpipe= 0x0040, /* applic has SIGPIPE set to SIG_IGN, do not protect */
adns_if_checkc_entex= 0x0100, /* do consistency checks on entry/exit to adns funcs */
- adns_if_checkc_freq= 0x0300, /* do consistency checks very frequently (slow!) */
+ adns_if_checkc_freq= 0x0300 /* do consistency checks very frequently (slow!) */
} adns_initflags;
typedef enum {
/* permanent errors */
adns_s_nxdomain,
adns_s_nodata,
+
+ adns_s_max_permfail= 499
} adns_status;
typedef struct {
adns_status status;
char *cname; /* always NULL if query was for CNAME records */
- char *owner; /* only set if requested in query flags */
+ char *owner; /* only set if requested in query flags, and may be 0 on error anyway */
adns_rrtype type; /* guaranteed to be same as in query */
time_t expires; /* expiry time, defined only if _s_ok, nxdomain or nodata. NOT TTL! */
int nrrs, rrsz; /* nrrs is 0 if an error occurs */
* values.
*
* For _wait and _check failures are reported in the answer
- * structure, and only 0, ESRCH or (for _check) EWOULDBLOCK is
+ * structure, and only 0, ESRCH or (for _check) EAGAIN is
* returned: if no (appropriate) requests are done adns_check returns
- * EWOULDBLOCK; if no (appropriate) requests are outstanding both
+ * EAGAIN; if no (appropriate) requests are outstanding both
* adns_query and adns_wait return ESRCH.
*
* Additionally, _wait can return EINTR if you set adns_if_eintr.
int adns_init_strcfg(adns_state *newstate_r, adns_initflags flags,
FILE *diagfile /*0=>discard*/, const char *configtext);
+/* Configuration:
+ * adns_init reads /etc/resolv.conf, which is expected to be (broadly
+ * speaking) in the format expected by libresolv, and then
+ * /etc/resolv-adns.conf if it exists. adns_init_strcfg is instead
+ * passed a string which is interpreted as if it were the contents of
+ * resolv.conf or resolv-adns.conf. In general, configuration which
+ * is set later overrides any that is set earlier.
+ *
+ * Standard directives understood in resolv[-adns].conf:
+ *
+ * nameserver <address>
+ * Must be followed by the IP address of a nameserver. Several
+ * nameservers may be specified, and they will be tried in the order
+ * found. There is a compiled in limit, currently 5, on the number
+ * of nameservers. (libresolv supports only 3 nameservers.)
+ *
+ * search <domain> ...
+ * Specifies the search list for queries which specify
+ * adns_qf_search. This is a list of domains to append to the query
+ * domain. The query domain will be tried as-is either before all
+ * of these or after them, depending on the ndots option setting
+ * (see below).
+ *
+ * domain <domain>
+ * This is present only for backward compatibility with obsolete
+ * versions of libresolv. It should not be used, and is interpreted
+ * by adns as if it were `search' - note that this is subtly
+ * different to libresolv's interpretation of this directive.
+ *
+ * sortlist <addr>/<mask> ...
+ * Should be followed by a sequence of IP-address and netmask pairs,
+ * separated by spaces. They may be specified as
+ * eg. 172.30.206.0/24 or 172.30.206.0/255.255.255.0. Currently up
+ * to 15 pairs may be specified (but note that libresolv only
+ * supports up to 10).
+ *
+ * options
+ * Should followed by one or more options, separated by spaces.
+ * Each option consists of an option name, followed by optionally
+ * a colon and a value. Options are listed below.
+ *
+ * Non-standard directives understood in resolv[-adns].conf:
+ *
+ * clearnameservers
+ * Clears the list of nameservers, so that further nameserver lines
+ * start again from the beginning.
+ *
+ * include <filename>
+ * The specified file will be read.
+ *
+ * Additionally, adns will ignore lines in resolv[-adns].conf which
+ * start with a #.
+ *
+ * Standard options understood:
+ *
+ * debug
+ * Enables debugging output from the resolver, which will be written
+ * to stderr.
+ *
+ * ndots:<count>
+ * Affects whether queries with adns_qf_search will be tried first
+ * without adding domains from the searchlist, or whether the bare
+ * query domain will be tried last. Queries which contain at least
+ * <count> dots will be tried bare first. The default is 1.
+ *
+ * Non-standard options understood:
+ *
+ * adns_checkc:none
+ * adns_checkc:entex
+ * adns_checkc:freq
+ * Changes the consistency checking frequency; this overrides the
+ * setting of adns_if_check_entex, adns_if_check_freq, or neither,
+ * in the flags passed to adns_init.
+ *
+ * There are a number of environment variables which can modify the
+ * behaviour of adns. They take effect only if adns_init is used, and
+ * the caller of adns_init can disable them using adns_if_noenv. In
+ * each case there is both a FOO and an ADNS_FOO; the latter is
+ * interpreted later so that it can override the former. Unless
+ * otherwise stated, environment variables are interpreted after
+ * resolv[-adns].conf are read, in the order they are listed here.
+ *
+ * RES_CONF, ADNS_RES_CONF
+ * A filename, whose contets are in the format of resolv.conf.
+ *
+ * RES_CONF_TEXT, ADNS_RES_CONF_TEXT
+ * A string in the format of resolv.conf.
+ *
+ * RES_OPTIONS, ADNS_RES_OPTIONS
+ * These are parsed as if they appeared in the `options' line of a
+ * resolv.conf. In addition to being parsed at this point in the
+ * sequence, they are also parsed at the very beginning before
+ * resolv.conf or any other environment variables are read, so that
+ * any debug option can affect the processing of the configuration.
+ *
+ * LOCALDOMAIN, ADNS_LOCALDOMAIN
+ * These are interpreted as if their contents appeared in a `search'
+ * line in resolv.conf.
+ */
+
int adns_synchronous(adns_state ads,
const char *owner,
adns_rrtype type,
void *context,
adns_query *query_r);
+/* The owner should be quoted in master file format. */
+
int adns_check(adns_state ads,
adns_query *query_io,
adns_answer **answer_r,
adns_answer **answer_r,
void **context_r);
+/* same as adns_wait but uses poll(2) internally */
+int adns_wait_poll(adns_state ads,
+ adns_query *query_io,
+ adns_answer **answer_r,
+ void **context_r);
+
void adns_cancel(adns_query query);
/* The adns_query you get back from _submit is valid (ie, can be
adns_queryflags flags,
void *context,
adns_query *query_r);
-/* type must be _r_ptr or _r_ptr_raw. _qf_search is ignored. */
+/* type must be _r_ptr or _r_ptr_raw. _qf_search is ignored.
+ * addr->sa_family must be AF_INET or you get ENOSYS.
+ */
void adns_finish(adns_state ads);
/* You may call this even if you have queries outstanding;
* adns_submit 2
* adns_submit 3
* adns_wait 1
- * adns_check 3 -> EWOULDBLOCK
+ * adns_check 3 -> EAGAIN
* adns_wait 2
* adns_wait 3
* ....
* from, or send outgoing data via, fd. Very like _processany. If it
* returns zero then fd will no longer be readable or writeable
* (unless of course more data has arrived since). adns will _only_
- * that fd and only in the manner specified, regardless of whether
+ * use that fd and only in the manner specified, regardless of whether
* adns_if_noautosys was specified.
*
* adns_processexceptional should be called when select(2) reports an
int *len_r,
const void *datap, char **data_r);
/*
-
* Get information about a query type, or convert reply data to a
* textual form. type must be specified, and the official name of the
* corresponding RR type will be returned in *rrtname_r, and
const char *adns_strerror(adns_status st);
const char *adns_errabbrev(adns_status st);
+const char *adns_errtypeabbrev(adns_status st);
/* Like strerror but for adns_status values. adns_errabbrev returns
* the abbreviation of the error - eg, for adns_s_timeout it returns
- * "timeout". You MUST NOT call these functions with status values
+ * "timeout". adns_errtypeabbrev returns the abbreviation of the
+ * error class: ie, for values up to adns_s_max_XXX it will return the
+ * string XXX. You MUST NOT call these functions with status values
* not returned by the same adns library.
*/
~ianmdlvl / adns.git / blobdiff