Module bitfield

source code

Manage creation and modification of bitfields.

Classes

[hide private]

Bitfield
A bitfield, a indicating the pieces a peer has.

Functions

[hide private]

negsum(a)

source code

tuple of list of boolean

_int_to_booleans(x)
Convert an integer to a list of booleans.

source code

test_bitfield()
Test the bitfield implementation.

source code

Variables

[hide private]

list of tuple of boolean lookup_table = [(False, False, False, False, False, False, Fal...
A lookup table for converting characters to a tuple of booleans.

dictionary reverse_lookup_table = {(False, False, False, False, False, Fa...
A reverse mapping of lookup_table.

i = 255

x = (True, True, True, True, True, True, True, True)

Function Details

[hide private]

_int_to_booleans(x)

source code

Convert an integer to a list of booleans.

Parameters:

x (int) - the integer to convert

Returns: tuple of list of boolean

the list of booleans

Variables Details

[hide private]

lookup_table

A lookup table for converting characters to a tuple of booleans. Each tuple has 8 booleans, which are true for all the bits in the character that are set.

Type:: list of tuple of boolean

Value:

[(False, False, False, False, False, False, False, False),
 (False, False, False, False, False, False, False, True),
 (False, False, False, False, False, False, True, False),
 (False, False, False, False, False, False, True, True),
 (False, False, False, False, False, True, False, False),
 (False, False, False, False, False, True, False, True),
 (False, False, False, False, False, True, True, False),
 (False, False, False, False, False, True, True, True),
...

reverse_lookup_table

A reverse mapping of lookup_table. The keys are the tuples of 8 booleans, which map to values that are the characters the tuples were created from.

Type:: dictionary

Value:

{(False, False, False, False, False, False, False, False): '\x00',
 (False, False, False, False, False, False, False, True): '\x01',
 (False, False, False, False, False, False, True, False): '\x02',
 (False, False, False, False, False, False, True, True): '\x03',
 (False, False, False, False, False, True, False, False): '\x04',
 (False, False, False, False, False, True, False, True): '\x05',
 (False, False, False, False, False, True, True, False): '\x06',
 (False, False, False, False, False, True, True, True): '\x07',
...