Bamboo Panda

✏️ Editing: wire.py

# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license

import contextlib
import struct
from typing import Iterator, Optional, Tuple

import dns.exception
import dns.name

class Parser:
    def __init__(self, wire: bytes, current: int = 0):
        self.wire = wire
        self.current = 0
        self.end = len(self.wire)
        if current:
            self.seek(current)
        self.furthest = current

def remaining(self) -> int:
        return self.end - self.current

def get_bytes(self, size: int) -> bytes:
        assert size >= 0
        if size > self.remaining():
            raise dns.exception.FormError
        output = self.wire[self.current : self.current + size]
        self.current += size
        self.furthest = max(self.furthest, self.current)
        return output

def get_counted_bytes(self, length_size: int = 1) -> bytes:
        length = int.from_bytes(self.get_bytes(length_size), "big")
        return self.get_bytes(length)

def get_remaining(self) -> bytes:
        return self.get_bytes(self.remaining())

def get_uint8(self) -> int:
        return struct.unpack("!B", self.get_bytes(1))[0]

def get_uint16(self) -> int:
        return struct.unpack("!H", self.get_bytes(2))[0]

def get_uint32(self) -> int:
        return struct.unpack("!I", self.get_bytes(4))[0]

def get_uint48(self) -> int:
        return int.from_bytes(self.get_bytes(6), "big")

def get_struct(self, format: str) -> Tuple:
        return struct.unpack(format, self.get_bytes(struct.calcsize(format)))

def get_name(self, origin: Optional["dns.name.Name"] = None) -> "dns.name.Name":
        name = dns.name.from_wire_parser(self)
        if origin:
            name = name.relativize(origin)
        return name

def seek(self, where: int) -> None:
        # Note that seeking to the end is OK!  (If you try to read
        # after such a seek, you'll get an exception as expected.)
        if where < 0 or where > self.end:
            raise dns.exception.FormError
        self.current = where

@contextlib.contextmanager
    def restrict_to(self, size: int) -> Iterator:
        assert size >= 0
        if size > self.remaining():
            raise dns.exception.FormError
        saved_end = self.end
        try:
            self.end = self.current + size
            yield
            # We make this check here and not in the finally as we
            # don't want to raise if we're already raising for some
            # other reason.
            if self.current != self.end:
                raise dns.exception.FormError
        finally:
            self.end = saved_end

@contextlib.contextmanager
    def restore_furthest(self) -> Iterator:
        try:
            yield None
        finally:
            self.current = self.furthest

T	Name	Size
📁	..	-
📁	__pycache__	-
📁	dnssecalgs	-
📁	quic	-
📁	rdtypes	-
📄	__init__.py	1.62 KB
📄	_asyncbackend.py	2.30 KB
📄	_asyncio_backend.py	8.76 KB
📄	_ddr.py	5.12 KB
📄	_features.py	2.33 KB
📄	_immutable_ctx.py	2.40 KB
📄	asyncbackend.py	2.73 KB
📄	asyncquery.py	26.22 KB
📄	asyncresolver.py	17.43 KB
📄	dnssec.py	39.74 KB
📄	dnssectypes.py	1.76 KB
📄	e164.py	3.88 KB
📄	edns.py	14.91 KB
📄	entropy.py	4.14 KB
📄	enum.py	3.60 KB
📄	exception.py	5.82 KB
📄	flags.py	2.69 KB
📄	grange.py	2.10 KB
📄	immutable.py	1.97 KB
📄	inet.py	5.64 KB
📄	ipv4.py	2.49 KB
📄	ipv6.py	6.45 KB
📄	message.py	64.45 KB
📄	name.py	41.67 KB
📄	namedict.py	3.91 KB
📄	nameserver.py	9.68 KB
📄	node.py	12.37 KB
📄	opcode.py	2.67 KB
📄	query.py	53.55 KB
📄	rcode.py	4.06 KB
📄	rdata.py	28.77 KB
📄	rdataclass.py	2.91 KB
📄	rdataset.py	16.36 KB
📄	rdatatype.py	7.17 KB
📄	renderer.py	10.99 KB
📄	resolver.py	71.83 KB
📄	reversename.py	3.74 KB
📄	rrset.py	8.96 KB
📄	serial.py	3.52 KB
📄	set.py	8.88 KB
📄	tokenizer.py	23.03 KB
📄	transaction.py	22.11 KB
📄	tsig.py	11.15 KB
📄	tsigkeyring.py	2.57 KB
📄	ttl.py	2.91 KB
📄	update.py	11.96 KB
📄	version.py	1.88 KB
📄	versioned.py	11.49 KB
📄	win32util.py	8.89 KB
📄	wire.py	2.76 KB
📄	xfr.py	12.96 KB
📄	zone.py	50.87 KB
📄	zonefile.py	27.27 KB
📄	zonetypes.py	690.00 B