/usr/lib/python3/dist-packages/yaml/reader.py is in python3-yaml 3.10-4build4.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 | # This module contains abstractions for the input stream. You don't have to
# looks further, there are no pretty code.
#
# We define two classes here.
#
# Mark(source, line, column)
# It's just a record and its only use is producing nice error messages.
# Parser does not use it for any other purposes.
#
# Reader(source, data)
# Reader determines the encoding of `data` and converts it to unicode.
# Reader provides the following methods and attributes:
# reader.peek(length=1) - return the next `length` characters
# reader.forward(length=1) - move the current position to `length` characters.
# reader.index - the number of the current character.
# reader.line, stream.column - the line and the column of the current character.
__all__ = ['Reader', 'ReaderError']
from .error import YAMLError, Mark
import codecs, re
class ReaderError(YAMLError):
def __init__(self, name, position, character, encoding, reason):
self.name = name
self.character = character
self.position = position
self.encoding = encoding
self.reason = reason
def __str__(self):
if isinstance(self.character, bytes):
return "'%s' codec can't decode byte #x%02x: %s\n" \
" in \"%s\", position %d" \
% (self.encoding, ord(self.character), self.reason,
self.name, self.position)
else:
return "unacceptable character #x%04x: %s\n" \
" in \"%s\", position %d" \
% (self.character, self.reason,
self.name, self.position)
class Reader(object):
# Reader:
# - determines the data encoding and converts it to a unicode string,
# - checks if characters are in allowed range,
# - adds '\0' to the end.
# Reader accepts
# - a `bytes` object,
# - a `str` object,
# - a file-like object with its `read` method returning `str`,
# - a file-like object with its `read` method returning `unicode`.
# Yeah, it's ugly and slow.
def __init__(self, stream):
self.name = None
self.stream = None
self.stream_pointer = 0
self.eof = True
self.buffer = ''
self.pointer = 0
self.raw_buffer = None
self.raw_decode = None
self.encoding = None
self.index = 0
self.line = 0
self.column = 0
if isinstance(stream, str):
self.name = "<unicode string>"
self.check_printable(stream)
self.buffer = stream+'\0'
elif isinstance(stream, bytes):
self.name = "<byte string>"
self.raw_buffer = stream
self.determine_encoding()
else:
self.stream = stream
self.name = getattr(stream, 'name', "<file>")
self.eof = False
self.raw_buffer = None
self.determine_encoding()
def peek(self, index=0):
try:
return self.buffer[self.pointer+index]
except IndexError:
self.update(index+1)
return self.buffer[self.pointer+index]
def prefix(self, length=1):
if self.pointer+length >= len(self.buffer):
self.update(length)
return self.buffer[self.pointer:self.pointer+length]
def forward(self, length=1):
if self.pointer+length+1 >= len(self.buffer):
self.update(length+1)
while length:
ch = self.buffer[self.pointer]
self.pointer += 1
self.index += 1
if ch in '\n\x85\u2028\u2029' \
or (ch == '\r' and self.buffer[self.pointer] != '\n'):
self.line += 1
self.column = 0
elif ch != '\uFEFF':
self.column += 1
length -= 1
def get_mark(self):
if self.stream is None:
return Mark(self.name, self.index, self.line, self.column,
self.buffer, self.pointer)
else:
return Mark(self.name, self.index, self.line, self.column,
None, None)
def determine_encoding(self):
while not self.eof and (self.raw_buffer is None or len(self.raw_buffer) < 2):
self.update_raw()
if isinstance(self.raw_buffer, bytes):
if self.raw_buffer.startswith(codecs.BOM_UTF16_LE):
self.raw_decode = codecs.utf_16_le_decode
self.encoding = 'utf-16-le'
elif self.raw_buffer.startswith(codecs.BOM_UTF16_BE):
self.raw_decode = codecs.utf_16_be_decode
self.encoding = 'utf-16-be'
else:
self.raw_decode = codecs.utf_8_decode
self.encoding = 'utf-8'
self.update(1)
NON_PRINTABLE = re.compile('[^\x09\x0A\x0D\x20-\x7E\x85\xA0-\uD7FF\uE000-\uFFFD]')
def check_printable(self, data):
match = self.NON_PRINTABLE.search(data)
if match:
character = match.group()
position = self.index+(len(self.buffer)-self.pointer)+match.start()
raise ReaderError(self.name, position, ord(character),
'unicode', "special characters are not allowed")
def update(self, length):
if self.raw_buffer is None:
return
self.buffer = self.buffer[self.pointer:]
self.pointer = 0
while len(self.buffer) < length:
if not self.eof:
self.update_raw()
if self.raw_decode is not None:
try:
data, converted = self.raw_decode(self.raw_buffer,
'strict', self.eof)
except UnicodeDecodeError as exc:
character = self.raw_buffer[exc.start]
if self.stream is not None:
position = self.stream_pointer-len(self.raw_buffer)+exc.start
else:
position = exc.start
raise ReaderError(self.name, position, character,
exc.encoding, exc.reason)
else:
data = self.raw_buffer
converted = len(data)
self.check_printable(data)
self.buffer += data
self.raw_buffer = self.raw_buffer[converted:]
if self.eof:
self.buffer += '\0'
self.raw_buffer = None
break
def update_raw(self, size=4096):
data = self.stream.read(size)
if self.raw_buffer is None:
self.raw_buffer = data
else:
self.raw_buffer += data
self.stream_pointer += len(data)
if not data:
self.eof = True
#try:
# import psyco
# psyco.bind(Reader)
#except ImportError:
# pass
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