bitstruct

About

This module is intended to have a similar interface as the python struct module, but working on bits instead of primitive data types (char, int, …).

Project homepage: https://github.com/eerimoq/bitstruct

Documentation: http://bitstruct.readthedocs.org/en/latest

Installation

pip install bitstruct

Example usage

A basic example of packing and unpacking four integers using the format string 'u1u3u4s16':

>>> from bitstruct import *
>>> pack('u1u3u4s16', 1, 2, 3, -4)
b'\xa3\xff\xfc'
>>> unpack('u1u3u4s16', b'\xa3\xff\xfc')
(1, 2, 3, -4)
>>> calcsize('u1u3u4s16')
24

An example compiling the format string once, and use it to pack and unpack data:

>>> import bitstruct
>>> cf = bitstruct.compile('u1u3u4s16')
>>> cf.pack(1, 2, 3, -4)
b'\xa3\xff\xfc'
>>> cf.unpack(b'\xa3\xff\xfc')
(1, 2, 3, -4)

The unpacked values can be named by assigning them to variables or by wrapping the result in a named tuple:

>>> from bitstruct import *
>>> from collections import namedtuple
>>> MyName = namedtuple('myname', [ 'a', 'b', 'c', 'd' ])
>>> unpacked = unpack('u1u3u4s16', b'\xa3\xff\xfc')
>>> myname = MyName(*unpacked)
>>> myname
myname(a=1, b=2, c=3, d=-4)
>>> myname.c
3

An example of packing and unpacking an unsinged integer, a signed integer, a float, a boolean, a byte string and a string:

>>> from bitstruct import *
>>> pack('u5s5f32b1r13t40', 1, -1, 3.75, True, b'\xff\xff', 'hello')
b'\x0f\xd0\x1c\x00\x00?\xffhello'
>>> unpack('u5s5f32b1r13t40', b'\x0f\xd0\x1c\x00\x00?\xffhello')
(1, -1, 3.75, True, b'\xff\xf8', 'hello')
>>> calcsize('u5s5f32b1r13t40')
96

The same format string and values as in the previous example, but using LSB (Least Significant Bit) first instead of the default MSB (Most Significant Bit) first:

>>> from bitstruct import *
>>> pack('<u5s5f32b1r13t40', 1, -1, 3.75, True, b'\xff\xff', 'hello')
b'\x87\xc0\x00\x03\x80\xbf\xff\xf666\xa6\x16'
>>> unpack('<u5s5f32b1r13t40', b'\x87\xc0\x00\x03\x80\xbf\xff\xf666\xa6\x16')
(1, -1, 3.75, True, b'\xff\xf8', 'hello')
>>> calcsize('<u5s5f32b1r13t40')
96

An example of unpacking values from a hexstring and a binary file:

>>> from bitstruct import *
>>> from binascii import unhexlify
>>> unpack('s17s13r24', unhexlify('0123456789abcdef'))
(582, -3751, b'\xe2j\xf3')
>>> with open("test.bin", "rb") as fin:
...     unpack('s17s13r24', fin.read(8))
...
...
(582, -3751, b'\xe2j\xf3')

Change endianness of the data with byteswap, and then unpack the values:

>>> from bitstruct import *
>>> packed = pack('u1u3u4s16', 1, 2, 3, 1)
>>> unpack('u1u3u4s16', byteswap('12', packed))
(1, 2, 3, 256)

Release files for bitstruct 3.5.0

For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.

Source distribution (sdist)

Source distribution for bitstruct 3.5.0
File	Size	Uploaded
bitstruct-3.5.0.tar.gz	16.8 kB	Oct 14, 2017	Details

Built distribution (wheel)

Table of built distributions (wheels) for bitstruct 3.5.0
File	Interpreter	ABI	Platform	Reset
bitstruct-3.5.0-py2.py3-none-any.whl 7.6 kB Oct 14, 2017	Python 2, Python 3	none	any	Details

Total release size: 24.3 kB

Release files / bitstruct-3.5.0.tar.gz

Download URL	bitstruct-3.5.0.tar.gz
Size	16.8 kB
Tags	Source
SHA-256 checksum How to use checksums	`6a67f91eaec4aebb7e561c8a27b3c100140b9b18b6a57b293eed6cc4b8d24128`
BLAKE2b-256 checksum How to use checksums	`b291cd64871016cfa91f541d8335793449fbff7256df514f5baa880e4795efea`
Upload date	Oct 14, 2017
Uploaded using Trusted Publishing? What is trusted publishing?	No

Release files / bitstruct-3.5.0-py2.py3-none-any.whl

Download URL	bitstruct-3.5.0-py2.py3-none-any.whl
Size	7.6 kB
Tags	Python 2 Python 3
SHA-256 checksum How to use checksums	`68561e84ea112bcbc3042984495949653b1394e17a48496b46f22daff33de4c9`
BLAKE2b-256 checksum How to use checksums	`095bda83322a4b0e4c5fe366501693461ddf4a1de3a871f36ac6fbbe58e6b3bd`
Upload date	Oct 14, 2017
Uploaded using Trusted Publishing? What is trusted publishing?	No