晋太元中,武陵人捕鱼为业。缘溪行,忘路之远近。忽逢桃花林,夹岸数百步,中无杂树,芳草鲜美,落英缤纷。渔人甚异之,复前行,欲穷其林。 林尽水源,便得一山,山有小口,仿佛若有光。便舍船,从口入。初极狭,才通人。复行数十步,豁然开朗。土地平旷,屋舍俨然,有良田、美池、桑竹之属。阡陌交通,鸡犬相闻。其中往来种作,男女衣着,悉如外人。黄发垂髫,并怡然自乐。 见渔人,乃大惊,问所从来。具答之。便要还家,设酒杀鸡作食。村中闻有此人,咸来问讯。自云先世避秦时乱,率妻子邑人来此绝境,不复出焉,遂与外人间隔。问今是何世,乃不知有汉,无论魏晋。此人一一为具言所闻,皆叹惋。余人各复延至其家,皆出酒食。停数日,辞去。此中人语云:“不足为外人道也。”(间隔 一作:隔绝) 既出,得其船,便扶向路,处处志之。及郡下,诣太守,说如此。太守即遣人随其往,寻向所志,遂迷,不复得路。 南阳刘子骥,高尚士也,闻之,欣然规往。未果,寻病终。后遂无问津者。
|
Server : Apache System : Linux srv.rainic.com 4.18.0-553.47.1.el8_10.x86_64 #1 SMP Wed Apr 2 05:45:37 EDT 2025 x86_64 User : rainic ( 1014) PHP Version : 7.4.33 Disable Function : exec,passthru,shell_exec,system Directory : /usr/include/bind9/dns/ |
Upload File : |
/*
* Copyright (C) Internet Systems Consortium, Inc. ("ISC")
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, you can obtain one at https://mozilla.org/MPL/2.0/.
*
* See the COPYRIGHT file distributed with this work for additional
* information regarding copyright ownership.
*/
#ifndef DNS_BYADDR_H
#define DNS_BYADDR_H 1
/*****
***** Module Info
*****/
/*! \file dns/byaddr.h
* \brief
* The byaddr module provides reverse lookup services for IPv4 and IPv6
* addresses.
*
* MP:
*\li The module ensures appropriate synchronization of data structures it
* creates and manipulates.
*
* Reliability:
*\li No anticipated impact.
*
* Resources:
*\li TBS
*
* Security:
*\li No anticipated impact.
*
* Standards:
*\li RFCs: 1034, 1035, 2181, TBS
*\li Drafts: TBS
*/
#include <stdbool.h>
#include <isc/lang.h>
#include <isc/event.h>
#include <dns/types.h>
ISC_LANG_BEGINDECLS
/*%
* A 'dns_byaddrevent_t' is returned when a byaddr completes.
* The sender field will be set to the byaddr that completed. If 'result'
* is ISC_R_SUCCESS, then 'names' will contain a list of names associated
* with the address. The recipient of the event must not change the list
* and must not refer to any of the name data after the event is freed.
*/
typedef struct dns_byaddrevent {
ISC_EVENT_COMMON(struct dns_byaddrevent);
isc_result_t result;
dns_namelist_t names;
} dns_byaddrevent_t;
/*
* This option is deprecated since we now only consider nibbles.
#define DNS_BYADDROPT_IPV6NIBBLE 0x0001
*/
/*% Note DNS_BYADDROPT_IPV6NIBBLE is now deprecated. */
#define DNS_BYADDROPT_IPV6INT 0x0002
isc_result_t
dns_byaddr_create(isc_mem_t *mctx, isc_netaddr_t *address, dns_view_t *view,
unsigned int options, isc_task_t *task,
isc_taskaction_t action, void *arg, dns_byaddr_t **byaddrp);
/*%<
* Find the domain name of 'address'.
*
* Notes:
*
*\li There is a reverse lookup format for IPv6 addresses, 'nibble'
*
*\li The 'nibble' format for that address is
*
* \code
* 1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.e.f.ip6.arpa.
* \endcode
*
*\li #DNS_BYADDROPT_IPV6INT can be used to get nibble lookups under ip6.int.
*
* Requires:
*
*\li 'mctx' is a valid mctx.
*
*\li 'address' is a valid IPv4 or IPv6 address.
*
*\li 'view' is a valid view which has a resolver.
*
*\li 'task' is a valid task.
*
*\li byaddrp != NULL && *byaddrp == NULL
*
* Returns:
*
*\li #ISC_R_SUCCESS
*\li #ISC_R_NOMEMORY
*
*\li Any resolver-related error (e.g. #ISC_R_SHUTTINGDOWN) may also be
* returned.
*/
void
dns_byaddr_cancel(dns_byaddr_t *byaddr);
/*%<
* Cancel 'byaddr'.
*
* Notes:
*
*\li If 'byaddr' has not completed, post its #DNS_EVENT_BYADDRDONE
* event with a result code of #ISC_R_CANCELED.
*
* Requires:
*
*\li 'byaddr' is a valid byaddr.
*/
void
dns_byaddr_destroy(dns_byaddr_t **byaddrp);
/*%<
* Destroy 'byaddr'.
*
* Requires:
*
*\li '*byaddrp' is a valid byaddr.
*
*\li The caller has received the #DNS_EVENT_BYADDRDONE event (either because
* the byaddr completed or because dns_byaddr_cancel() was called).
*
* Ensures:
*
*\li *byaddrp == NULL.
*/
isc_result_t
dns_byaddr_createptrname(isc_netaddr_t *address, bool nibble,
dns_name_t *name);
isc_result_t
dns_byaddr_createptrname2(isc_netaddr_t *address, unsigned int options,
dns_name_t *name);
/*%<
* Creates a name that would be used in a PTR query for this address. The
* nibble flag indicates that the 'nibble' format is to be used if an IPv6
* address is provided, instead of the 'bitstring' format. Since we dropped
* the support of the bitstring labels, it is expected that the flag is always
* set. 'options' are the same as for dns_byaddr_create().
*
* Requires:
*
* \li 'address' is a valid address.
* \li 'name' is a valid name with a dedicated buffer.
*/
ISC_LANG_ENDDECLS
#endif /* DNS_BYADDR_H */