python-extensions

because life's too short for slow software

Palindrome

First example of making Python code faster.

Fibonacci

Second example.

Debugging

Notes about debugging C extensions.

C2Assembly

Notes about translating C programs to Assembly.

Writing C extensions for Python

Main reference for this topic: https://docs.python.org/3/extending/extending.html

At a minimum 2 files are needed:

1. cpalindromemodule.c - C extension module
2. setup.py - script used to create Python extension

cpalindromemodule.c

#define PY_SSIZE_T_CLEAN
#include <Python.h>

static PyObject *cpalindrome_is_palindrome(PyObject *self, PyObject *args) {
}

static PyMethodDef CPalindromeMethods[] = {
    {"is_palindrome", cpalindrome_is_palindrome, METH_VARARGS, 
     "check is string is palindrome"},
    {NULL, NULL, 0, NULL}};

static struct PyModuleDef cpalindromemodule = {
    PyModuleDef_HEAD_INIT, "cpalindrome",
    "A C implementation of is_palindrome function", -1, CPalindromeMethods};

PyMODINIT_FUNC PyInit_cpalindrome(void) { return PyModule_Create(&cpalindromemodule); }

setup.py

from distutils.core import setup, Extension

def main():
    setup(name="cpalindrome",
          version="1.0.0",
          description="is_palindrome check in C",
          ext_modules=[Extension("cpalindrome", ["cpalindromemodule.c"])])

if __name__ == '__main__':
    main()

To install C extension you can run pip install -e . in the directory with C code and setup.py

Writing Assembly extensions for Python

Since I already have assembly version of fibonacci and palindrome programs there was only one logical next step - writing Python extensions in pure assembly. After a couple of hours spent on that, I realized that the main issue is creating Python module data structures in Assembly and putting everything together. I tried to follow Writing Python Extensions in Assembly and I was able to make it work on Linux, but not on Mac which I'm currently working on. Leaving it for now, as I'm already satisfied with the state of this project.