Skip to content
A command line tool for generating source code to read and write binary data.
Branch: master
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Permalink
Type Name Latest commit message Commit time
Failed to load latest commit information.
.media
tests
wick
.gitignore
.travis.yml
LICENSE
MANIFEST.in
README.md
makefile
requirements.txt
setup.py

README.md

wick

wick

Python 3.6 PyPI version Build Status

wick is a Python command line tool that automatically generates file I/O source code for working with binary data.

Why?

I was working on a project that involved reverse engineering file formats and I found that most data structures tend to be composed of several simpler data structures. I also noticed that the simpler structures were all very boilerplate. So I created this tool to write the simple structures for me, and I can do the more interesting work of composing them into the larger structure.

Supported Target Languages

  • C#
  • JavaScript
  • Python

Installation

$ pip install wick

Usage

$ wick example.h Python

What exactly does it do?

Let's walk through a concrete example.

Say we have binary data that is a sequence of records that are represented by a string name and an integer id. First we create a record.h file that contains a C struct representation of this data:

// record.h

// Simple Record
struct Record {
    // Record name
    char name[64];

    // Record id.
    unsigned char id;
};

Then we run wick on the file:

$ wick record.h Python

Which will then create a record.py file whose contents look like:

# record.py
import struct


class Record:
    """Simple Record object

    Attributes:
        name: Record name

        id: Record id.
    """

    format = '<64sB'
    size = struct.calcsize(format)

    __slots__ = (
        'name',
        'id'
    )

    def __init__(self,
                 name,
                 id):
        self.name = name.split(b'\x00')[0].decode('ascii') if type(name) is bytes else name
        self.id = id

    @classmethod
    def write(cls, file, record):
        record_data = struct.pack(cls.format,
                                  record.name.encode('ascii'),
                                  record.id)

        file.write(record_data)

    @classmethod
    def read(cls, file):
        record_data = file.read(cls.size)
        record_struct = struct.unpack(cls.format, record_data)

        return Record(*record_struct)

Then we can import this code into Python and do work.

Read Data

with open(path, 'rb') as file:
    rec = Record.read(file)

Write Data

with open(path, 'wb') as file:
    rec = Record(b'name', 0)
    Record.write(file, rec)

Unpack Lots of Data

import struct

# Assuming the file only contains Record data
with open(path, 'rb') as file:
    recs = [Record(*chunk) for chunk in struct.iter_unpack(Record.format, file.read())]

Contributing

Have a bug fix or a new feature you'd like to see in wick? Send it our way! Please make sure you create an issue that addresses your fix/feature so we can discuss the contribution.

  1. Fork this repo!
  2. Create your feature branch: git checkout -b features/add-javascript-code-generator
  3. Commit your changes: git commit -m 'Implemented Javascript code generator'
  4. Push the branch: git push origin add-javascript-code-generator
  5. Submit a pull request.
  6. Create an issue.

License

MIT

See the license document for the full text.

You can’t perform that action at this time.
You signed in with another tab or window. Reload to refresh your session. You signed out in another tab or window. Reload to refresh your session.