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from __future__ import (absolute_import, print_function, division)
def isascii(s):
try:
s.decode("ascii")
except ValueError:
return False
return True
# best way to do it in python 2.x
def bytes_to_int(i):
return int(i.encode('hex'), 16)
def cleanBin(s, fixspacing=False):
"""
Cleans binary data to make it safe to display. If fixspacing is True,
tabs, newlines and so forth will be maintained, if not, they will be
replaced with a placeholder.
"""
parts = []
for i in s:
o = ord(i)
if (o > 31 and o < 127):
parts.append(i)
elif i in "\n\t" and not fixspacing:
parts.append(i)
else:
parts.append(".")
return "".join(parts)
def hexdump(s):
"""
Returns a set of tuples:
(offset, hex, str)
"""
parts = []
for i in range(0, len(s), 16):
o = "%.10x" % i
part = s[i:i + 16]
x = " ".join("%.2x" % ord(i) for i in part)
if len(part) < 16:
x += " "
x += " ".join(" " for i in range(16 - len(part)))
parts.append(
(o, x, cleanBin(part, True))
)
return parts
def setbit(byte, offset, value):
"""
Set a bit in a byte to 1 if value is truthy, 0 if not.
"""
if value:
return byte | (1 << offset)
else:
return byte & ~(1 << offset)
def getbit(byte, offset):
mask = 1 << offset
if byte & mask:
return True
class BiDi:
"""
A wee utility class for keeping bi-directional mappings, like field
constants in protocols. Names are attributes on the object, dict-like
access maps values to names:
CONST = BiDi(a=1, b=2)
assert CONST.a == 1
assert CONST.get_name(1) == "a"
"""
def __init__(self, **kwargs):
self.names = kwargs
self.values = {}
for k, v in kwargs.items():
self.values[v] = k
if len(self.names) != len(self.values):
raise ValueError("Duplicate values not allowed.")
def __getattr__(self, k):
if k in self.names:
return self.names[k]
raise AttributeError("No such attribute: %s", k)
def get_name(self, n, default=None):
return self.values.get(n, default)
def pretty_size(size):
suffixes = [
("B", 2 ** 10),
("kB", 2 ** 20),
("MB", 2 ** 30),
]
for suf, lim in suffixes:
if size >= lim:
continue
else:
x = round(size / float(lim / 2 ** 10), 2)
if x == int(x):
x = int(x)
return str(x) + suf
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