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。
| DIR:/lib/python3.9/site-packages/dns/rdtypes/ANY/ |
| Current File : //lib/python3.9/site-packages/dns/rdtypes/ANY/LOC.py |
# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license
# Copyright (C) 2003-2007, 2009-2011 Nominum, Inc.
#
# Permission to use, copy, modify, and distribute this software and its
# documentation for any purpose with or without fee is hereby granted,
# provided that the above copyright notice and this permission notice
# appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND NOMINUM DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL NOMINUM BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
# OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
import struct
import dns.exception
import dns.immutable
import dns.rdata
_pows = tuple(10**i for i in range(0, 11))
# default values are in centimeters
_default_size = 100.0
_default_hprec = 1000000.0
_default_vprec = 1000.0
# for use by from_wire()
_MAX_LATITUDE = 0x80000000 + 90 * 3600000
_MIN_LATITUDE = 0x80000000 - 90 * 3600000
_MAX_LONGITUDE = 0x80000000 + 180 * 3600000
_MIN_LONGITUDE = 0x80000000 - 180 * 3600000
def _exponent_of(what, desc):
if what == 0:
return 0
exp = None
for i, pow in enumerate(_pows):
if what < pow:
exp = i - 1
break
if exp is None or exp < 0:
raise dns.exception.SyntaxError("%s value out of bounds" % desc)
return exp
def _float_to_tuple(what):
if what < 0:
sign = -1
what *= -1
else:
sign = 1
what = round(what * 3600000)
degrees = int(what // 3600000)
what -= degrees * 3600000
minutes = int(what // 60000)
what -= minutes * 60000
seconds = int(what // 1000)
what -= int(seconds * 1000)
what = int(what)
return (degrees, minutes, seconds, what, sign)
def _tuple_to_float(what):
value = float(what[0])
value += float(what[1]) / 60.0
value += float(what[2]) / 3600.0
value += float(what[3]) / 3600000.0
return float(what[4]) * value
def _encode_size(what, desc):
what = int(what)
exponent = _exponent_of(what, desc) & 0xF
base = what // pow(10, exponent) & 0xF
return base * 16 + exponent
def _decode_size(what, desc):
exponent = what & 0x0F
if exponent > 9:
raise dns.exception.FormError("bad %s exponent" % desc)
base = (what & 0xF0) >> 4
if base > 9:
raise dns.exception.FormError("bad %s base" % desc)
return base * pow(10, exponent)
def _check_coordinate_list(value, low, high):
if value[0] < low or value[0] > high:
raise ValueError(f"not in range [{low}, {high}]")
if value[1] < 0 or value[1] > 59:
raise ValueError("bad minutes value")
if value[2] < 0 or value[2] > 59:
raise ValueError("bad seconds value")
if value[3] < 0 or value[3] > 999:
raise ValueError("bad milliseconds value")
if value[4] != 1 and value[4] != -1:
raise ValueError("bad hemisphere value")
@dns.immutable.immutable
class LOC(dns.rdata.Rdata):
"""LOC record"""
# see: RFC 1876
__slots__ = [
"latitude",
"longitude",
"altitude",
"size",
"horizontal_precision",
"vertical_precision",
]
def __init__(
self,
rdclass,
rdtype,
latitude,
longitude,
altitude,
size=_default_size,
hprec=_default_hprec,
vprec=_default_vprec,
):
"""Initialize a LOC record instance.
The parameters I{latitude} and I{longitude} may be either a 4-tuple
of integers specifying (degrees, minutes, seconds, milliseconds),
or they may be floating point values specifying the number of
degrees. The other parameters are floats. Size, horizontal precision,
and vertical precision are specified in centimeters."""
super().__init__(rdclass, rdtype)
if isinstance(latitude, int):
latitude = float(latitude)
if isinstance(latitude, float):
latitude = _float_to_tuple(latitude)
_check_coordinate_list(latitude, -90, 90)
self.latitude = tuple(latitude)
if isinstance(longitude, int):
longitude = float(longitude)
if isinstance(longitude, float):
longitude = _float_to_tuple(longitude)
_check_coordinate_list(longitude, -180, 180)
self.longitude = tuple(longitude)
self.altitude = float(altitude)
self.size = float(size)
self.horizontal_precision = float(hprec)
self.vertical_precision = float(vprec)
def to_text(self, origin=None, relativize=True, **kw):
if self.latitude[4] > 0:
lat_hemisphere = "N"
else:
lat_hemisphere = "S"
if self.longitude[4] > 0:
long_hemisphere = "E"
else:
long_hemisphere = "W"
text = "%d %d %d.%03d %s %d %d %d.%03d %s %0.2fm" % (
self.latitude[0],
self.latitude[1],
self.latitude[2],
self.latitude[3],
lat_hemisphere,
self.longitude[0],
self.longitude[1],
self.longitude[2],
self.longitude[3],
long_hemisphere,
self.altitude / 100.0,
)
# do not print default values
if (
self.size != _default_size
or self.horizontal_precision != _default_hprec
or self.vertical_precision != _default_vprec
):
text += " {:0.2f}m {:0.2f}m {:0.2f}m".format(
self.size / 100.0,
self.horizontal_precision / 100.0,
self.vertical_precision / 100.0,
)
return text
@classmethod
def from_text(
cls, rdclass, rdtype, tok, origin=None, relativize=True, relativize_to=None
):
latitude = [0, 0, 0, 0, 1]
longitude = [0, 0, 0, 0, 1]
size = _default_size
hprec = _default_hprec
vprec = _default_vprec
latitude[0] = tok.get_int()
t = tok.get_string()
if t.isdigit():
latitude[1] = int(t)
t = tok.get_string()
if "." in t:
(seconds, milliseconds) = t.split(".")
if not seconds.isdigit():
raise dns.exception.SyntaxError("bad latitude seconds value")
latitude[2] = int(seconds)
l = len(milliseconds)
if l == 0 or l > 3 or not milliseconds.isdigit():
raise dns.exception.SyntaxError("bad latitude milliseconds value")
if l == 1:
m = 100
elif l == 2:
m = 10
else:
m = 1
latitude[3] = m * int(milliseconds)
t = tok.get_string()
elif t.isdigit():
latitude[2] = int(t)
t = tok.get_string()
if t == "S":
latitude[4] = -1
elif t != "N":
raise dns.exception.SyntaxError("bad latitude hemisphere value")
longitude[0] = tok.get_int()
t = tok.get_string()
if t.isdigit():
longitude[1] = int(t)
t = tok.get_string()
if "." in t:
(seconds, milliseconds) = t.split(".")
if not seconds.isdigit():
raise dns.exception.SyntaxError("bad longitude seconds value")
longitude[2] = int(seconds)
l = len(milliseconds)
if l == 0 or l > 3 or not milliseconds.isdigit():
raise dns.exception.SyntaxError("bad longitude milliseconds value")
if l == 1:
m = 100
elif l == 2:
m = 10
else:
m = 1
longitude[3] = m * int(milliseconds)
t = tok.get_string()
elif t.isdigit():
longitude[2] = int(t)
t = tok.get_string()
if t == "W":
longitude[4] = -1
elif t != "E":
raise dns.exception.SyntaxError("bad longitude hemisphere value")
t = tok.get_string()
if t[-1] == "m":
t = t[0:-1]
altitude = float(t) * 100.0 # m -> cm
tokens = tok.get_remaining(max_tokens=3)
if len(tokens) >= 1:
value = tokens[0].unescape().value
if value[-1] == "m":
value = value[0:-1]
size = float(value) * 100.0 # m -> cm
if len(tokens) >= 2:
value = tokens[1].unescape().value
if value[-1] == "m":
value = value[0:-1]
hprec = float(value) * 100.0 # m -> cm
if len(tokens) >= 3:
value = tokens[2].unescape().value
if value[-1] == "m":
value = value[0:-1]
vprec = float(value) * 100.0 # m -> cm
# Try encoding these now so we raise if they are bad
_encode_size(size, "size")
_encode_size(hprec, "horizontal precision")
_encode_size(vprec, "vertical precision")
return cls(rdclass, rdtype, latitude, longitude, altitude, size, hprec, vprec)
def _to_wire(self, file, compress=None, origin=None, canonicalize=False):
milliseconds = (
self.latitude[0] * 3600000
+ self.latitude[1] * 60000
+ self.latitude[2] * 1000
+ self.latitude[3]
) * self.latitude[4]
latitude = 0x80000000 + milliseconds
milliseconds = (
self.longitude[0] * 3600000
+ self.longitude[1] * 60000
+ self.longitude[2] * 1000
+ self.longitude[3]
) * self.longitude[4]
longitude = 0x80000000 + milliseconds
altitude = int(self.altitude) + 10000000
size = _encode_size(self.size, "size")
hprec = _encode_size(self.horizontal_precision, "horizontal precision")
vprec = _encode_size(self.vertical_precision, "vertical precision")
wire = struct.pack(
"!BBBBIII", 0, size, hprec, vprec, latitude, longitude, altitude
)
file.write(wire)
@classmethod
def from_wire_parser(cls, rdclass, rdtype, parser, origin=None):
(
version,
size,
hprec,
vprec,
latitude,
longitude,
altitude,
) = parser.get_struct("!BBBBIII")
if version != 0:
raise dns.exception.FormError("LOC version not zero")
if latitude < _MIN_LATITUDE or latitude > _MAX_LATITUDE:
raise dns.exception.FormError("bad latitude")
if latitude > 0x80000000:
latitude = (latitude - 0x80000000) / 3600000
else:
latitude = -1 * (0x80000000 - latitude) / 3600000
if longitude < _MIN_LONGITUDE or longitude > _MAX_LONGITUDE:
raise dns.exception.FormError("bad longitude")
if longitude > 0x80000000:
longitude = (longitude - 0x80000000) / 3600000
else:
longitude = -1 * (0x80000000 - longitude) / 3600000
altitude = float(altitude) - 10000000.0
size = _decode_size(size, "size")
hprec = _decode_size(hprec, "horizontal precision")
vprec = _decode_size(vprec, "vertical precision")
return cls(rdclass, rdtype, latitude, longitude, altitude, size, hprec, vprec)
@property
def float_latitude(self):
"latitude as a floating point value"
return _tuple_to_float(self.latitude)
@property
def float_longitude(self):
"longitude as a floating point value"
return _tuple_to_float(self.longitude)
|